HomeMy WebLinkAboutNC0000272_Color Reduction Plan Trial Docs_20120201 i
Process Trial Documents cited in Update to the Color Reduction Implementation Plan —
February 2012
Attached in order cited
Evergreen 2011 — Annual Progress Report on Color, submitted to NC DWQ to meet
requirements of Part I A.(8) item 8 of the May 2010 NPDES Permit, Evergreen Packaging
Canton Mill, July 1, 2011.
Adams 2002a — Blue Ridge Paper Products - Canton Mill — Trial Report — Hydrogen Peroxide
(H2O2) on Hardwood Eo Stage, Bill Adams Process Engineer, Blue Ridge Paper Products Inc.
Canton Mill, July 2, 2002.
Adams 2002b — Blue Ridge Paper Products - Canton Mill — Process History Report —
D-100 Kappa Factors Performance / Monitoring, Bill Adams Process Engineer, Blue Ridge
Paper Products Inc. Canton Mill, July 10, 2002.
Miller 2011 — H2O2 Hardwood and Pine Bleaching Trial Results, internal technical memo, Bill
Miller, process engineer for Evergreen Packaging, January 24, 2012.
McCracken 2011 — Statistical Overview of Peroxide Application on Softwood and Hardwood
Fiberlines for Color at Canton Mill, P Qtr 2011, internal data evaluation prepared by Nick
McCracken and the Canton Mill Color Team for Evergreen Packaging, December 2011.
PITC 201 lb — Report 2011-054 — Evergreen Packaging Bleaching, Canton NC, Pruyn's Island
Technical Center, August 3, 2011.
McDonough 2011 - Laboratory Study of Likely Effects of Oxidatively Intensifying the
Extraction States at Evergreen Packaging's Canton, NC Mill, Progress Report (DRAFT),
Thomas J. McDonough, consultant to Evergreen Packaging, February 10, 2012.
PITC 2001 — Report 2001-068, Part 1 —Laboratory CK and Lo-Solids Cooking with O-Do-Eop-
D Bleaching Sequences on Softwood Furnish from Blue Ridge Paper, Part I —Softwood Results,
Pruyn's Island Technical Center, December 6, 2001.
PITC 2011 a— Report 2010-081 —Laboratory Cooking and Bleaching for Evergreen Packaging
Canton,NC, Pruyn's Island Technical Center, January 31, 2011.
McDonough 2011 — Laboratory Study of Likely Effects of Installing Two-Stage Oxygen
Delignification at Evergreen Packaging's Canton, NC Mill, Thomas J. McDonough, consultant
to Evergreen Packaging, June 29, 2011.
FEB 2 2 2012
e
July 1, 2011 — Annual Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No.NC0000272
I. Introduction
Part I A.(8.) item 8 of the May 2010 NPDES Permit states — The facility will provide
annual progress reports to the Division on the color reduction efforts. This report fulfills
the requirements of Part I A.(8.) item 8. Specifically, the report documents projects and
best management practice (BMP) refinements completed by the Canton Mill Color Team
during the period May 2006 through May 2011. The Color Team continued work on
color performance improvement including several recommendations incorporated into the
final permit between the May 2006 application and May 2010 NPDES permit renewal.
II. Background
Levels of color in the wastewater effluent from the Canton Mill are among the best of
Kraft pulp and paper mills in the world [EKONO August 2005, NCASI August 2006].
This high level of color performance is achieved by in-process controls and best
management practices. The mill will continue to operate the controls and practices
proven successful for color prevention. These controls and practices go well beyond the'
requirements of the EPA Cluster Rule for Pulp and Paper (40 CFR 430, Subpart B).
Many, such as the Bleach Filtrate Recycling ProcessTM, are unique to the Canton Mill.
The May 2010 NPDES permit includes a daily maximum effluent true color limit of
105,250 lbs per day. The permit also specifies a monthly average true color limit of
52,000 lbs per day and an annual average (calendar year) true color limit of 38,020 lbs
Page 1
July 1, 2011 — Annual Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No. NC0000272
per day. Compliance with these effluent limits requires significant management of mill
operations related to color. Prevention of wastewater effluent color is a priority for mill
operations every day.
III. Color Performance
Figure 1 illustrates the color performance of the Canton Mill since 1997. The mill has
sustained and continued the color reductions achieved under the 1997 and 2001 NPDES
permits. Annual average effluent true color in Figure 1 is presented in units of 1000 Ibs
per day. The calculation of effluent color as a daily mass (lbs) is defined in Part I A.(8.)
items 2&3 of the permit: color (lbs/day) = effluent flow (mgd) x effluent true color
(platinum cobalt units) x 8.34. Effluent true color is measured using NCASI method
253 (1971).
Figure 1 - Annual Average Effluent Color
Blue Ridge Paper Canton Mill, 1997 thru 2010
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Page 2
July 1, 2011 — Annual Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No.NC0000272
The best color performance of the Canton Mill occurs during normal, or full, production.
At normal production, the internal recycling and recovery of process filtrates, pulping
liquors and other process wastewaters are balanced. Color materials are contained within
the Kraft pulping process at efficiency greater than 99 percent. Color performance is
affected by process variability. Color materials can be lost during startup and shutdown
associated with a process upset, production curtailment or unplanned outage. Because of
both economic impact and adverse affect on color performance, the mill has strong
incentive to maintain process reliability and operate at normal production level.
Effluent color early in 2009 was affected by weak product demand related to the 2008
Financial Crisis and global recession that resulted in a lower overall rate of mill
production. Additionally, there was an unplanned pulp mill outage and color event in
September 2009 associated with a recovery furnace tube failure that required emergency,
life safety shutdown of the No. 10 Recovery Furnace. That single, unplanned outage
event added more than 1000 lbs per day to the 2009. annual average effluent color.
Effluent color at the end of 2009 and during the winter of 2010 was affected by extended
cold wet weather and regional wood supply shortages that resulted in lower than normal
rates of pulp production.
Page 3
July 1, 2011 — Annual Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No.NC0000272
IV. Color Proiects and Refinements to Best Management Practices
The Canton Mill has a standing Color Team that routinely meets to review color
performance. The Color Team members include managers, supervisors and engineers
involved with production, maintenance, wastewater treatment and regulatory affairs. The
Color Team scope includes:
• Monitor color performance and the effectiveness of mill systems to prevent
effluent color
• Identify and track corrective actions related to Cluster Rule BMP color events
• Plan and review process trials related to effluent color
• Plan and review the effectiveness of capital and expense projects related to
effluent color
The Color Team is continuously evaluating projects, trials and process initiatives. Not all
of these are successful. Significant Color Team activities between 2001 and 2005 are
documented in the May 2006 Color Compliance Report [BRPPI May 2006]. Significant
activities from May 2006 through May 2011 are outlined in Tables 1 and 2. Capital
projects in Table 1 are identified by Capital Improvement Project (CIP) number. Other
projects were completed on operations and maintenance expense. Direct spending on
Color Team related projects, trials and initiatives identified in Tables I and 2 during the
period May 2006 through May 2011 exceed $ 3.0 MM capital and expense These costs
are in addition to the on-going cost to operate and maintain color prevention systems at
the Canton Mill.
Page 4
July 1, 2011 — Annual Progress Report on Color
Blue:Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No.NC0000272
Table 1
Color Team Capital and Maintenance Projects
2006 - 2011
Year Project Description and Cost Information for Capital Projects
2006 Check valve installed in the#11 Recovery Boiler sump pump line. This
prevents collected color materials from being inadvertently pumped into the
CRP Feed Tank instead of the Wash Water Tank for.processing through the
Evaporators. BMP improvement.
o Completed November 2006, cnsd*
2007 Continued 4th stage hardwood BSW shower replacement begun in 2005.
These shower bars were installed to improve washing and reduce carry-over
into the bleach plant. Liebergott Recommendation.
o Completed during 2007 Hwd semi-annual outage
o CIP - 230014
o Cost- $90,000
CRP sump installation and controls. This sump was installed to contain color
material event releases from the CRP system building. Also allows
collection of color material related to CRP maintenance boil out. BMP
improvement related to 2006 and 2007 color events.
o Completed December 2007
o CIP - 218675
o Cost- $164,000
Piping to collect Sarco Strainer washes directly to Wash Water Tank instead
of through sump area. Manual system of piping and valves. BMP
improvement.
o Completed in December 2007
o CIP -232234
o Cost- $64,000
High level interlocks on CRP slurry tank. High-level indicator shuts the#11
Recovery Boiler sump gate and the CRP sewer gate exiting the building.
This allows material to be picked up in the sump if any overflows. BMP
improvement related to 2007 color event.
o Completed September 2007, cnsd*
Page 5
July 1, 2011 — Annual Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No. NC0000272
Table 1
Color Team Capital and Maintenance Projects
2006 - 2011
Year Project Description and Cost Information for Capital Projects
2007 Mini-Hoods on No. 10 Smelt Dissolving Tank(SMDT). Allows substitution
of weak wash for clean water in SMDT demister creating more process
demand for weak wash and reducing high pH material discharged to sewer.
Related to TRW Recommendations regarding prevention of sewer-generated
color—high pH.
o Completed 2Q 2007, cnsd*
Created audible alarms for mill sewers in the DCS for WWTP. Allows
WWTP operators to locate potential elevated color streams in the mill sewers
and contact specific areas of the mill.. BMP improvement.
o Completed 2007, cnsd*
2008 Dregs filter feed improvements to improve reliability and reduce frequency
of dregs sewering/overflow. Includes pipe separation, new lines and pump
upgrades. Related to TRW Recommendations regarding prevention of sewer
generated color—sulfide materials and high pH.
o Completed in 2Q of 2008
o CIP - 232333
o Cost- $200,000
Creation of sample point inside CRP building to monitor color loading to
mill sewer. This point is being used to monitor operations, in regards to
color,within the CRP system. BMP improvement.
o Completed 2008, cnsd*
Determine CRP boil out strategy. Study included taking boil out water
samples at periodic intervals to determine color load to mill sewer. BMP
improvement possible with CRP recovery sump completed in 2007.
o Completed 2008, cnsd*
New set points for digester hog line conductivity probe. Better detection of
digester liquor heater leaks and better process data for monitoring liquor
heater failures. BMP improvement.
o Completed March 2008, cnsd*
Page 6
July 1, 2011 — Annual Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No. NC0000272
Table 1
Color Team Capital and Maintenance Projects
2006 -2011
Year Project Description and Cost Information for Capital Projects
2009 Remote activation of shutoff valves on firewater quench to#11 Recovery
Boiler cyclones during Emergency Shutdown Procedure (ESP). This
mitigates potential volume of high color material.from cyclone overflow
during an ESP. BMP improvement related to Sep 2009 color event.
o Identified in 4Q 2009
o Completed on No. 11 Recovery Furnace 3Q 2010, cnsd*
o Completed on No. 10 Recovery Furnace 2Q 2011, cnsd*
Curbing around East Camp Branch color material storage tank, pumps and
transfer piping. This is a proactive measure to segregate and prevent losses
of high color material to the#4 sewer. BMP improvement.
o Completed in 2009
o CIP -239011
o Cost—portion of$128,000
Installation of separate sump and conductivity meter for East Camp Branch
tank, pumps and transfer piping. The sump and meter allow any losses from
the East Tank to be monitored and contained before entering the#4 sewer.
BMP improvement. -
o Completed in 2009
o CIP - 239011
o Cost—portion of$128,000
Installation of 120 ft of concrete barrier around East Heavy Liquor Tank.
BMP improvement in the Recovery area. BMP improvement.
o Completed in 2009
o CIP—264956
o Cost- $20,000
Replacement of section (250 ft) of Wash Water line running from
evaporators to Wash Water Tank. This is a proactive measure to prevent
losses from this transfer line. BMP improvement.
o Completed in 2009
o CIP—292829
o Cost—portion of$160,000
Page 7
July 1, 2011 — Annual Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No.NC0000272
Table 1
Color Team Capital and Maintenance Projects
2006 - 2011
Year Project Description and Cost Information for Capital Projects
2009 New flow meter at Evaporator area South Sump. Meter allows operators to
determine if the sump is picking up any losses from the Evaporator area.
BMP improvement.
o Completed March 2009, cnsd*
Level transmitter for Lime Kiln Sample Collection Tank put into DCS.
Allows an operator to monitor tank level to prevent overflows of high pH
material to the sewer and reduce the Sewer Generated Color phenomena.
Related to TRW Recommendations regarding prevention of sewer generated
color—high pH.
o Completed 2009, cnsd*
Manual back to Automatic on sumps. Sump indications now turn red and
alert operators that they are in manual mode on DCS screens. BMP
improvement related to color event.
o Completed January 2009, cnsd*
Replaced pump in the Evaporator area South Sump with a different style
pump for increased reliability. New pump is a submersible type. BMP
improvement related to color event.
o Completed 2009, cnsd*
Modified process lines and equipment on 5`h effect of Swenson evaporators
to allow on-the-run cleaning. BMP improvement for process reliability to
avoid carryover of color material into condensate systems. Reduces the
volume of color material generated by evaporator boil out during outages.
Color material carry over from evaporators into condensates is related to
TRW Recommendations to prevent sewer-generated color.
o Completed 3Q 2009, cnsd*
Replaced slide rails and gates for isolating primary clarifiers at the Primary
Influent Headbox at the WWTP. New gates are faster and easier for WWTP
operators to divert high color material to the spare primary clarifier for
capture,batch treatment and attenuation. BMP sustaining measure and
improvement.
o Completed December 2009
o CIP—287478
o Cost—$265,000
Page 8
July 1, 2011 — Annual Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No.NC0000272
Table 1
Color Team Capital and Maintenance Projects
2006 - 2011
Year Project Description and Cost Information for Capital Projects
2010 East Heavy/Tall Oil Sump transfer line repair..This was a proactive measure
to prevent color material losses from this transfer line. BMP sustaining
measure.
o Completed August 2010, cnsd*
Replaced decant line from Turpentine loading to 4A manhole: This is a
proactive measure to prevent losses from this transfer line. BMP sustaining
measure.
o Completed 2010
o CIP—315223
o Cost- $275,000
Repair and recoating of west side of Camp Branch compound. Project to
maintain integrity of spill containment. BMP sustaining measure.
o Completed 2010
o CIP—315588
o Cost- $235,000
Several black liquor transfer line replacements including East Heavy storage
tank and West GB Discharge. BMP sustaining measure.
o Completed 2010, cnsd*
Replaced conductivity and level switches in East Heavy compound with
new, more reliable type. BMP improvement.
o Completed 3Q 2010, cnsd*
Relocation of sewer conductivity meter below Digester Area sumps. BMP
optimization in this area.
o Completed November 2010, cnsd*
Red Liquor Tank shell replacement/repairs. BMP sustaining measure.
o Completed May 2010
o CIP— 266446
o Cost—$265,000
Page 9
July 1, 2011 — Annual Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No.NC0000272
Table 1
Color Team Capital and Maintenance Projects
2006 - 2011
Year Project Description and Cost Information for Capital Projects
2010 Mini-Hoods on No. 11 Smelt Dissolving Tank(SMDT). Allows substitution
of weak wash for clean water in SNOT demister creating more process
demand for weak wash and reducing high pH material discharged to sewer.
Related to TRW Recommendations regarding prevention of sewer-generated
color—high pH.
o Completed 3Q 2010, cnsd*
North White Liquor Tank shell replacement/repairs. BMP sustaining
measure and project related to TRW Recommendations regarding prevention
of sewer-generated color—high pH white liquor.
o Completed Dec 2010
o CIP—322435
o Cost—$724,000
2011 Process lines to allow front-end boil out of West GB Evaporator. Allows
more frequent, less intense evaporator cleaning. BMP improvement for
process reliability to avoid carryover of color material into condensate
systems. Reduces the volume of color material generated by evaporator boil
out during outages. Color material carry over from evaporators into
condensates is related to TRW Recommendations to prevent sewer-generated
color.
o Completed May 2011, cnsd*
Repaired drain valves on No. 2 and 3 Primary Clarifiers. Allows isolation of
one of these larger volume clarifiers as the spare clarifier for high color
material diversion during semi-annual outages. BMP sustaining measure.
o Completed March 2011, cnsd*
Pine Weak Liquor Tank shell replacement/repairs. BMP sustaining
measure.
o Completed May 2011
o CIP— 331985
o Cost—$349,000
*cnsd—cost not separately determined, completed on operations and
maintenance expense
Page 10
July 1, 2011 — Annual Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No.NC0000272
Table 2
Color Team BMP Refinements, Trials and Process Improvements
2006 - 2011
Years Refinement,Trial and/or Improvement
2006. Liebergott Process Improvements
on-going o Improve performance of vacuum washers
o Evaluate the elimination of wash water bypass on 151 decker shower
o Evaluate the elimination of bypass of Eo filtrate to decker filtrate tank
o Improve performance of decker showers on Pine
2007 Metso Project and Training
o Shared savings program
o CLOZ use study to have a lower Kappa factor, knowledge carried
forward
2007 Strategy change in Hardwood Pre-bleach on showers. Original strategy was
on-going to wash better with chance of overflows. Now manage to prevent those
overflows.
2007 Thoroughly clean and jet lines and hardwood washer screens during each
on-going scheduled outage.
2007 More extensive jetting/cleaning in fiberlines during semi-annual outages.
on-going
2008 MRP improvements/time scheduled maintenance and operator rounds to
on-going increase reliability.
2008 CRP boil out strategy. Amount of time boil out material is picked up.
on-going Possible with CRP sump project completed in 2007.
2008 Use membrane caustic�with lower chloride concentration. Helps overall
on-going efficiency of BFR system.
2009 Optimize use of polyamine for black liquor color in primary treatment during
on-going color events. Batch treatment, as well as short period continuous use when
influent is affected by black liquor.
2009 Swenson 5 effect spray bar strategy. Ability to clean evaporator on-the-run.
on-going Improves process reliability and reduces volume of color material to recover
during outages.
2010 Weak wash purge strategy to minimize potential sewer-generated color
on-going during process upset, outage or reduced pulp mill production when demand
for weak wash is out of balance with supply in causticizin .
2011 When both fiberlines are down,process contents of one of the spill tanks
through the evaporators to free up spill tank volume before starting up.
Page 11
July 1, 2011 — Annual.Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No. NC0000272
Table 2
Color Team BMP Refinements, Trials and Process Improvements
2006 - 2011
Year(s) Refinement, Trial and/or Improvement
2011 Alternative polymer study by Chemtreat at WWTP. Compared against
current polyamine polymer in use for batch treatment of black color
materials. No difference in color performance.
2011 West'GB Evaporator partial boil out strategy. Ability to clean process during
on-going short outages as opportunities arise. Improves process reliability and
reduces volume of color material to recover during outages.
Several of the projects and process improvements listed in Tables 1 and 2 are related to
2006 Liebergott recommendations for existing process optimization [GL&V 2006].
These include projects for brown stock washing improvement and target pulp bleach
Kappa factor. Other projects and improvements are related to sewer-generated color and
polymer use optimization, which are Technology Review Workgroup (TRW) evaluation
recommendations in Part I A.(8.) item 103-of the May 2010 NPDES Permit. The
complete application to renew the NPDES permit was submitted by the Canton Mill in
May 2006. The permit renewal process including review by the TRW, public comment
and public hearings was completed in May 2010. During this time, the Canton Mill
Color Team continued work on color performance improvement including several
recommendations incorporated into the final permit.
V. Summary
Of the many color improvement initiatives evaluated and implemented at the Canton
Mill, the following are essential to current(2011) effluent color performance:
Page 12
July 1, 2011 — Annual Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No.NC0000272
• OD 100TM process — oxygen delignification, elemental chlorine-free (ECF)
bleaching and enhanced fiberline brown stock washing
• Bleach Filtrate Recyclinim (BFR) with the Minerals Removal Process (MRP)
and the Chlorine Removal Process (CRP)
• Cluster Rule Best Management Practices (BMP) program with color as the BMP
monitoring parameter to detect process upsets and the loss of pulping liquors to
the mill sewer system
• Extensive sumps and systems to detect pulping liquor losses to capture and
recover color materials within the pulp mill process
• Spare primary clarifier maintained to capture, treat and attenuate high
concentration color materials that may exceed capacity of the in-process sump
and spill detection systems -
• Mechanical seals on pumps in digester and knotter areas to minimize dilution of
color materials that prevents efficient recovery
• Interconnection of process spill sumps and equipment to increase the working
volume for recovery of color materials during process upsets and outages
• Segregation of black liquor from green and white liquor to avoid contamination
that prevents recovery of black liquor materials '
• Segregation of bleach plant filtrates from high pH conditions in mill sewers to
reduce sewer-generated color
Page 13
July 1, 2011 — Annual Progress Report on Color
Blue Ridge Paper Products Inc. dba Evergreen Packaging
Canton,North Carolina
NPDES Permit No.NC0000272
• Management of high pH materials when process filtrates are out of balance due to
process upset or reduced pulp mill production
• Outage cleaning of pulp washers and evaporators to maintain performance and
reduce carry-over of color materials into bleach plants and into condensate
systems
• Low Flow Contingency Plan for Color [Evergreen 2011] and priority given to
color management every day.
The Canton Mill will continue to utilize the processes and practices proven successful for
wastewater effluent color prevention. Prevention of effluent color is a priority for mill
operations every day.
References
EKONO — Environmental Performance, Regulations and Technologies in the Pulp and
Paper Industry, EKONO Inc,August 2005.
NCASI—Technical Bulletin No. 919—Review of Color Control Technologies and Their
Applicability to Modern Kraft Pulp and Paper Mill, National Council for Air and Stream
Improvement, August 2006.
BRPPI — Color Compliance Report prepared to fulfill requirements of the December
2001 NPDES Permit for the Canton Mill, Blue Ridge Paper Products Inc., May 2006.
GL&V — Bleach Environmental Process Evaluation and Report prepared for Blue Ridge
Paper Products Inc., Canton Mill,Norman Liebergott and Lewis Shackford, July 2006.
Evergreen — Low Flow Contingency Plan for Color, submitted to NC DWQ on 26 May
2011 to meet requirements of Part I A.(8) item 12 of the May 2010 NPDES Permit, May
2011.
Page 14
J
Y ,
Blue Ridge Paper Products, Inc. - Trial Report
Hydrogen Peroxide(H2O2) on Hardwood Eo Stage - MTA #402230
TO: Michael Ferguson . DATE: July 2, 2002
Fibedine Superintendent
FROM: Bill Adams SUB: Apply H2O2 to HW Eo Stage
Principal Process Engineer
Background Summary:
Per N.Liebergott of Liebergott&Associates, Inc. and L.Shackford &W.Miller of GL&V, in their"Bleach
Environmental Process Evaluation and Report"dated June 8, 2001, a recommendation was made to run a trial
in which hydrogen peroxide (H2O2) is applied to the Hardwood Eo stage. The recommendation for this trial was
further included in Canton's 2001 NPDES Compliance Action List for October 1, 2003 Report.
Several previous attempts have been made to use H2O2 on the Hardwood Eo stage to replace some C102
applied to the"D"stages. These attempts have had limited success. Generally,the conclusion has been that
the presence of Non-Process Elements (NPE's) in the pulp react with the H2O2 to form radicals which do not
brighten the pulp and can cause a reduction of pulp strength as measured by pulp viscosity.
The H2O2 application point was relocated for this trial from the stock line between the thick stock pump (TSP)
and chemical mixer to a port on the chemical mixer. This move was considered the best available application
point for H2O.2 on Canton's HW Eo system.
A trial was planned for 2002 in two parts: Part I would apply H2O2 to the HW Eo stage at the rate of about 6
WAD Ton while providing data with which to further optimize the bleach plant; Part II would apply H2O2 at about
6 WAD Ton under conditions that would best demonstrate the effectiveness of H2O2 on HW Eo. The two parts
of the trial occurred before and after the HW Annual Outage, respectively.Total bleach application was
identified as an important factor in the trial work as well as sewer color, bleaching costs, and pulp quality.
To be considered successful, an equivalent amount of 0102 had to be removed to the amount of H2O2 applied,
on a chemical cost basis. Atofina supplies the mill's H2O2 and was requested to update their pricing for H2O2 for
this trial. Atofina chose to lower their H2O2 price to match the mill's standard C102 cost. This meant that for
every pound of H2O2 applied, a pound of C102 must be removed in order to break even. A lower H2O2 price
would have meant that less C102 must be removed for the amount of H2O2 applied.
Data from The PQ Corporation indicates a significant improvement in H2O2 performance with the addition of
MgSO4.As part of the trial, a"check trial"was planned in which one (1)tote-bin of MgSO4 would be applied to
the HW Eo stage in addition to the H2O2. If successful,further trial work would be needed to demonstrate
whether MgSO4 application with H2O2 could be made cost effectively.
Bill Adams (828) 646-2868 402230 H2O2 on HW As Page 1 7/9/02
' Blue Ridge Paper:Products, Inc. - Trial Report :!
Hydrogen Peroxide (H202) on Hardwood Eo Stage - MTA#402230
Priorto starting this trial,the Hardwood fiberline bleaching operation was optimized by the adjustment of the D-
100 stage pH and by the reduction of Oxygen (02) application to the Eo stage. Results from the optimization
projects are reported separately.
For comparison,data is included in the Data Summary from several consecutive years, at about the same time
of year that the trial work was performed. During the data set for 1998, H202 was being applied to the HW Eo
stage. Data from the most recent two (2) months prior to the trial (3/1/02 thru 5112102) and post-trial data are
available for comparison of recent data. The Data Summary summarizes these groups of data plus the two trial
parts and Post Trial data.
Trial Summary:
Part I of the trial was begun on 5/13/02 by beginning H202 application to the HW Eo mixer at about 6 Ibs/AD
Ton. Application rate was based on recommendations by Atofina, Canton's H202 supplier. Control is effected
by the DCS system based on an application set point input by the operator. During this phase of the trial, H2O2
was applied at the rate of 5.8 WAD Ton. There were no issues involving the H202 system during this phase of
the trial.
Based on the performance of the HW bleach plant during Part I, it was recommended that the lower limit for
' C102 application on the D-100 stage be moved from 0.65%to 0.55%, allowing a lower D-100 brightness to be
maintained. A temporary set of operating guidelines was developed for Part 11 of the trial-scheduled after the
HW Annual Outage.
Part 11 of the trial was begun on 6/3/02 by continuing H202 application to the Hardwood Eo mixer at about 6
WAD Ton. Control is effected by the DCS system based on an application set point input by the operator.
During this phase of the trial, H2O2 was applied at the rate of 5.7 WAD Ton. There was an operational issue
involving the H202 system during this phase of the trial when the H202 solution transfer pump to the Eo mixer
failed. Data are excluded from the summary during the pump failure.
Part 11 of the trial was completed on 6/19102 after MgSO4 was applied to the HW D-100 washer repulper to
enhance H202 performance.
To evaluate any effect the trial work might have had on sewer color,data from 2001 was collected, obvious out-
liers discarded, averaged and the standard deviations calculated. These data are included in the Data
Summary. Also attached are charts showing average colors,.average+/-1 Standard Deviation, and trial
averages for the most pertinent sewer colors.
Conclusion:
No changes in C102 application were observed. The Hardwood fiberline was operated in a normal manner with
the earlier noted exception of the D-100 stage optimization work(primarily limiting D-100 brightness to about 63
' ISO). Chemical demands were comparable to previous data periods. H202 application was ineffective and is
not cost effective.
Bill Adams (828) 646-2868 402230 H2O2 on HW.xls Page 2 7/9/02
Blue Ridge Paper Products, Inc. - Trial Report
Hydrogen Peroxide (H202) on Hardwood Eo Stage - MTA#402230
Non-process elements (NPE's) exist on Canton's fiberlines due to the degree of"closure"and water
recirculation. NPE's react preferentially with H2O2 to form radicals,which, in turn, attack the carbohydrates in
the pulp. As a result, H2O2 is exhausted before brightening can occur and pulp strength (as measured by
viscosity)can be lost.
There were no cost savings from this trial. In fact,the data suggest a cost increase of about$697,000 per year
with the application of H2O2 on HW Eo. Added H2O2 costs are about$620,000 per year,the balance is primarily
added C102 costs. Actual trial cost was$45,000 in direct H2O2 cost.
In evaluating any changes to sewer color numbers, a great many factors may be affecting sewer colors at any
given time, including pH's,specific streams and flows, temperatures,the presence (or absence) of active
calcium ions, etc. To be confident that a change might have had a direct effect on sewer color, a change should
occur that is no less than one (1)standard deviation from average;three.(3) standard deviations would increase
confidence to over 95%_
None of the measured color data shows a greater than one(1)standards deviation change from 2001 averages.
Therefore, it cannot be concluded that this trial had an effect on sewer color.
Recommendations:
Recommend NOT using hydrogen peroxide on the hardwood Eo stage at moderate application rates (up to 10
lb/Ton) except in cases of emergency or other extenuating reasons.
Recommend revising the D-100 stage lower C102 application limit upward from 0.55 to 0.60. The recommended
rate of 0.60 is less than the beginning minimum of 0.65.
Hexenuronic Acids:
Hexenuronsc Acids(Hex-A)are chemical groups that originate from hemicellulose, but chemically react more
like lignin. They form during the Kraft cook from certain acid groups in Xylans. Hex-A raises"PW or"K"
numbers, but Hex A does not darken the pulp. Hexenuronic acid was first described in publications in 1996.
Direct measurement of Hex A at the mill level is difficult. Hex-A is primarily a hardwood phenomenon due to
Xylan levels in hardwood being three (3)to four(4)times that of pine.
By consuming potassium permanganate, digester"PN" numbers report Hex-A. A typical hardwood_pulp may
have four(4) points of Hex-A with eight(8) points of lignin for a total"PN" of twelve (12). Removal of half the
remaining lignin in the 02 delignification stage reduces the"PN"by four(4) points but appears to reduce the
"PW by only 33%. By the start of the Eo stage, there is very little lignin left and most of the measured"PW is
Hex-A(3 parts Hex A+ 1 part lignin=4 "PN' .
Canton's hardwood delignification rate of around 33% is considered about normal for a single-stage 02
delignification system on hardwood pulp. Delignification is actually much betterthan the data suggests-
interference from Hexenuronic Acids makes the performance only appear to be poor.
Bill Adams (828)646-2868 402230 H2O2 on HW.xts Page 3 7/9/02
' Blue Ridge Paper Products, Inc. - Trial Report ( ,
Hydrogen Peroxide (H2O2) on Hardwood Eo Stage - MTA #402230
In the bleach plant, Hexenuronic Acids consume C102 and permanganate, but do not decrease the pulp's
brightness. Therefore, all of the Hex A does not need to be removed to bleach the pulp to high-brightness.
Hexenuronic Acids contribute to variation of pulp quality measurements.
Note: Thanks[ To Rogelio Vega-Canovas of Atofina for this information.
/ c �
Bill Adams (828)646-2868
Principal Process Engineer
CC: Bill Boris Johnnie Pearson
Derric Brown./ Melanie Samuels
Paul Geoghegan Steve Single
Chris l-ifka File(x2)
Pete Maxey
Bill Adams (828) 646-2868 402230 H2O2 on HW.xls Page 4 7/9/02
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9402230 HzOZ on HW Eo Stage Trial -Mill Sewer Color Data
WWTP Primary Influent Color WWTP Secondary Effluent Color
75000 55000
70000
50000
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60000 45000
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50000
35000
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Trial Part I Trial Part II Trial Part I Trial Part II
—Ave-1 Std —Average ®Ave+1 Std o Trial —Ave-1 Std —Average®Ave+1 Std O Trial
3A(Alkali) Sewer Color Hardwood Eo Effluent Color
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13.00 7.00
12.00 6.00
11.00 5.00 . 97
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6,pp 0.00
Trial Part I Trial Part II Trial Part I Trial Part II
'Ave-1 Std --Average ®Ave+ 1 Std O Trial —Ave-1 Std —Average —Ave! 1 Std O Trial
Bill Adams (828) 646-2868 402230 H2O2 on HW.xls 7/9102
H
Blue Ridge Paper - Canton Mill
Process History Report
i O: Michael Ferguson Data. July 10.2002
Fiberline Superintendent
FROM: Bill Adams SUB: Process History-D-100 Kappa Factors
Principal Process Engineer Performance/Monitoring
Background Summary:
Section A. (8.)5. Of the NPDES Permit(Permit No:NC0000272)requires the Canton Mill to address Process Optimization
items identified in the study commissioned by the EPA Tech Team(aka, the"Liebergott/GL&V Report'). The information
contained in this"Process History Report'addresses Item No's. 6&13 of this report-that is,to"reduce...D-1 stage
kappa factor to 0.20-0.24...'.
"Kappa Factor'is a mathematical method of stating the amount of active chlorine dioxide(CI02)applied per kappa unit,
the measure of residual Iignin in the pulp. Canton does not determine the kappa number of pulp directly; Instead,the
"K'number or"PN"number is determined. The kappa number can then be estimated based on the relationship of
kappa numbers to"PIN!"numbers. This relationship was checked in 1995 by Champion Corporate Technology for Canton.
The Kappa Factor formula is: %CI02 Applied in Whole Numbers ` 2.63 =Kappa Factor
Pre-Bleach Kappa Number
Kappa No. Conversion is: Kappa No. = 0.293+("K'No. ' 1.47)
Canton reports chemical application in terms of"Bleached Air Dry Tons"of pulp(BADT). "Air Dry"tons are defined by
industry convention to contain 10%moisture. "Air Dry"tons are the most common pulp unit used In the U.S.
`=='Air Dry"tons are determined from"Bone Dry"tons—that is, pulp.that has no moisture. When pulp consistencies are
determined,the results are generally on a"bone dry'basis.
References to"Kappa Factor'in text sources I have been able to review generally avoid specifying whether the units
are"air dry'or"bone dry'. An unscientific survey of peers and knowledgeable persons indicated that there Is not an
industry standard-about 2/3 would use"air dry"numbers, but nearly every person had to think about which values to
use.
After the Ltebergott/GL&V audit,the question as to what basis to use was raised. Canton has traditionally used the
"air dry'values,while the GL&V folks have traditionally used"bone dry'values. This difference in basis was not
discovered until after the technology report had been submitted.
Within the Canton Mill, the"air dry"vs."bone dry'discrepancy has caused confusion. The chemical application rates
used by the DCS on the softwood(#2 Fiberline)fiberllne are generally"bone dry'while the application rates used on the
hardwood (#1 Fiberline)fiberline are generally"air dry'. This discrepancy has existed from initial start-up of the DCS
controls on each fiberline and is planned to be resolved(going to"air dry'basis).
The discrepancy generally does not matter in terms of monitoring as actual chemical usage and actual"air dry'pulp
tons are used to calculate chemical usage reports for mill management However,the values shown on the DCS
are different from those calculated from daily data. Kappa Factors are calculated and displayed in the DCS system
using DCS application rates and OCS production rates. Neither of these values is"official"in that they are not used
to estimate reported costs, nor to determine and report pulp production.
However,the Liebergott/GL&V audit team observed the erroneous Kappa Factors displayed by the DCS and made the
above referenced recommendations that the mill reduce Kappa Factors.
iudits by a variety of suppliers have generally Indicated Canton's kappa factors to be average or a little lower than
average for the industry.
Bill Adams(828)646-2868 NPDES Items .xis Page 1 7/11/02
Summary of Process Changes:
decent fiberline bleaching changes that affect Kappa Factors are shown below. i•
5/17/01 D-1 Stage Optimization - Both Fiberiines
8/7/01 D-1 Stage Optimization - H202 Off Pine
11/1101 D-1 Stage Optimization - Pine Fiberiine
12/17/01 Pine Cooking Change (Extend Cooking Time)
2/5/02 HW Cooking Change (Extend Cooking Time)
3114/02 HW Optimization - D-100 pH
5/13/02 H2O2 Trial(HW)(Ended 6119102)
6/20102 Normal Operation
Shown below are charts showing Kappa Factors over time. Kappa Factors have been calculated using both Air Dry and
Bone Dry pulp tons.
Chart#1 -Pine D-100 Stage Kappa Factors
Pine D400 Stage Kappa Factors
m
o ^
0.290 , N o
N N n N O O
0.270 ^ N N Cl! O'O N N O
0.250 0 0 0
0.230 o
N C
0.190 a5 ? cy ?
0.170 n ) `
5i5
O? �qo °e
OKappa Factor-AD MKappa Factor-BD
Chart#2-Hardwood D-100 stage Kappa Factors
Hardwood D400 Stage Kappa Factors
m
0.310 ry N
0.290 N o _ ^
0
0.270 Cl! O1 N
0.250 15' o N o N ry
0.230 0 O1 O N N
N O O O N
19
n
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f
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Bill Adams(828)646-2868 NPDES Items .xis Page 2 7/11102
Average data for the three(3)days of the Liebergott/GL&V audit are separated in the above tables and marked in color.
,onclusions):
Pine Fiberline(see Chart#1): The data shows pine kappa factor to be about 0.22 to 0.24, a little higher than the
Liebergott/GL&V recommendation(AD Ton basis). The softwood fiberline is controlled so that about half of the total
Clo application is made on each stage, a strategy that has proven sound over nearly ten(10)years of operation.
A planned project to revise the softwood Og Delignification stage will reduce the kappa number of pulp going to the
bleach plant and reduce CIOZ demand. The kappa factor will also be reduced when the OZ Delig project is completed.
Color generated in the Pine D-100 stage is retained on the fiberline via the BFR" system.
Hardwood Fiberline(see Chart#2): The data shows HW kappa factor to be between 0.18 and'0.21 (AD Ton basis)which
Is lower than the Liebergott/GL&V recommendations. Other knowledgeable bleaching authorities have recommended
hardwood kappa factors at similar levels. No changes are indicated.
Recommendations:
Continue refining/optimizing bleach plant performance as necessary.
Dedicate the time required to revise the softwood DCS system to an"Air Dried"basis. Some time will be required to
explain the change to the operators whose reference numbers will be slightly changed.
Hexenuronic Acids:
Hexenuronlc Acids(Hex-A)are chemical groups that originate from hemicellulose, but chemically react more like lignin.
They form during the Kraft cook from certain acid groups in Xylans. Hex A raises"PM'or"K'"numbers and consumes CIO2,
ut Hex-A does not darken the pulp. Hexenuronic acid was first described in publications in 1996. Direct measurement
of Hex-A at the mill level is difficult. Hex A is primarily a hardwood phenomenon due to Xylan levels in hardwood being
three(3)to four(4)times that of pine.
By consuming potassium permanganate, digester"PN"numbers report Hex-A. Atypical hardwood pulp may have four(4)
points of Hex-A with eight(8)points of lignin for a total"PN"of twelve(12). Removal of half the remaining lignin in the
OZ Delignification stage reduces the"PW by four(4) points and appears to reduce the"PW by only 33%. By the start
of the Eo stage,there is very little lignin left and most of the measured"PIN!"is Hex-A(3 pts Hex A+ 1 pt lignin=4"PN").
Canton's hardwood delignification rate of around 33%is considered about normal for a single-stage 02,delignification
system on hardwood pulp. Delignification is actually much better than the data suggests-interference from Hexenuronic
Acids makes the performance appear to be poor.
In the bleach plant, Hexenuronlc Acids consume CI02 and permanganate, but do not decrease the pulp's brightness.
Therefore, all of the Hex-A does not need to be removed to bleach the pulp to high brightness. Hexenuronic Acids contribute
to variation of pulp quality measurements.
Note: Thanksl To Rogelio Vega-Canvas of Atofina for this information.
Bill Adams
Principal Process Engineer
CC: Bill Boris ` Johnnie Pearson
r Derric Brown ✓ Melanie Samuels
Paul Geoghegan Steve Single
Chris Ufka File(x2)
Pete Maxey
Bill Adams(828)646-2868 NPDES Items.xis Page 3 7/11/02
f.evergreeff
packaging
Blue Ridge Paper Products Inc. - Canton Mill
To: Michael Ferguson, Barry Covington
Date: January 24, 2012
From: Bill Miller Subject: H2O2 Hardwood and Pine
bleaching trial results
Executive Summary:
A mill bleaching trial applying hydrogen peroxide (H2O2) to the Hardwood E and Pine Eo stages was
run for a 90 day period. The basis for the trial was to economically displace chlorine dioxide (C1O2) with
H2O2 in the bleach lines.
The 90 day trial period started June 23-25, 2011.
Fiberline operating data from I"quarter 2011 and June 2011 were investigated for establishing a
relevant economic baseline. The June 2011 period, following cold mill outage (CMO), was used.
The D 1 stage trial kappa factor(KF)of 0.20 was targeted for both lines. The H2O2 charges were
base loaded at 0.3% Ep stage Hardwood and 0.4% Eop stage Pine. These parameters established
by Evonik(supplier) and Evergreen. The Ep/Eop stage CEK increase resulting from the reduced
D 1 stage KF, would be partially offset by the H2O2 addition, minimizing C1O2 increase in the D2
stage. Costs savings from reduction in D 1 C1O2 usage would have to sufficient to offset cost of
H2O2 and increased D2 stage C1O2 usage. NaOH cost for pH control are also included.
For Hardwood, the July trial period looked promising, with a monthly average bleaching cost
reduction from$34.66 base to $34.09 trial for an abnormally low average Post 02 (PO) K-no of
6.1. In the Aug.-Sept. trial periods, average PO K-nos increased to a more normal range of 6.3-
7.7 due to seasonal digester cooking changes. The H2O2 Ep stage reinforcement was not
adequate to offset this added bleaching load at 0.2 KF.
The Hardwood trial operating parameters resulted in D 1 average C1O2 flow reduction of 14 gpm,
CEK increasing from a 1.8 baseline to 2.5 trial and D2 average C1O2 flow increase of 25 gpm.
Overall average trial bleaching costs increased from $34.66 to $35.46.
Hardwood average effluent color loading showed no appreciable net change. Average effluent
color loading increased from 5500#/day baseline to 8300#/day trail for D 1 stage and dropped
from 8700#/day to 6300#/day for Ep stage.
Page 2
The Pine trial overall bleaching costs never economically justified the H2O2 costs, even during
the July trial period with average PO K-nos of 8.0. Eop operating data indicates DI washer
discharge (COD) from MRP and Eop recycle is consuming H2O2 applied to Eop stage.
The Pine trial operating parameters resulted in a D 1 average C1O2 flow reduction of 6.5 gpm,
CEK increasing from a 2.7 baseline to 3.4 trial and D2 average C1O2 flow increase of 14 gpm.
Overall average trial bleaching costs increased from$33.08 to $37.60.
Pine average effluent color loading increased from 940#/day baseline to 1090#/day trail for DI
stage and dropped from 5840#/day to 18709/day for Eop stage. The Pine bleach plant average
closure increased from 78%baseline to 85.2%trial, which accounts for a good portion of the
Eop trial color loading decrease.
Based on these trial results, the application of H2O2 as bleaching reinforcement in the Hardwood
E stage and Pine Eo can not be economically justified.
1. Introduction:
A hydrogen peroxide (H2O2) trial run in the Canton No. 1 Hardwood and No.2 Pine Bleach
Plants was proposed due to favorable (H2O2) pricing from Evonik.
The trial economic justification is l#/T of dry H2O2, applied as delignification reinforcement into
the Hardwood E stage and the Pine Eo stage, has to displace %2#/T of applied C1O2. Cost
adjustments for increased NaOH usage as pH control were also taken into consideration.
The most effective approach for C1O2 reduction/displacement is reduce the D I kappa factors
(KF) when H2O2 is applied to the Eo/E stages. The strategy is to make up for the reduced D 1
stage delignification by applying the H2O2 to the extraction stage, minimizing any CEK
increase resulting from the D1 stage KF reduction. There will be an increase in D2 C1O2 charge,
which is typically about''/2 (#/#basis) D 1 stage C1O2 reduction.
A D I stage trial KF target of 0.20,with H2O2 base loaded at 0.3% Ep hardwood and 0.4%Eop
Pine,was established by Evonik and Evergreen.
C1O2 and NaOH usage and process parameters were monitored, and total bleaching chemical
costs weighed against the cost with and without H2O2. Bleach stage effluent color was also
monitored.
The H2O2 addition started June 23-25, 2011 for both lines for a 90 day trial. The period
following the CMO, June 1-25, was used as a baseline for bleach chemical cost comparison. The
period leading up to the CMO, Jan-Mar 2011 was also evaluated but not used in the comparison.
Page 3
The Pine trial was ended on Sept. 27,2010. The Hardwood trial was extended to Oct. 27, 2011
with increased D1 KF, but not used in financial evaluation.
2a. Hardwood Conclusions:
• Adjustments in D1 KF resulted in-elevated CEK(Graph 1 in Appendix). The best results
were at a D1 stage 0.226 KF, during the July period.
• The D1 0.22-0.23 KF range was only effective for average.6.1 kajaani k-no (5.6 PN).
• At 0.19-0.2 KF in D1, the H2O2 could not offset the loss of D1 delignification,resulting
in elevated CEK(Graph 1) and increased applied C1O2 in D2 (Graph 2). The 30 gpm
C1O2 reduction in D 1 resulted in 60 gpm C1O2 increase in D2. There was also a
corresponding increase in D2 NaOH for pH control (Graph 3).
• At 0.19-0.20 KF in D 1, the H2O2 cannot offset process changes resulting from seasonal
cooking K-no swings.
• Raising KF to 0.222 in Oct.period did not return favorable results due to unsteady
operation from liquor inventories and digester repairs.
• Hardwood average effluent color loading showed no appreciable net change at stage
sewers. Average effluent color loading increased from 5500#/day baseline to 8300#/day
trail for D 1 stage and dropped from 8700#/day to 6300#/day for Ep stage (Table 2 in
Results).
• Quality as measured by viscosity and brightness was unchanged by H2O2 addition(Table
2).
• Long term use of H2O2 in the hardwood E stage shows limited financial opportunity and
is not recommended.
2b. Pine Conclusions:
• Small adjustments in D1 KF from 0.226 to 0.21, resulted in elevated CEK(Graph 5). The
5 gpm C1O2 reduction in D1 resulted in 15-30 gpm C1O2 increase in D2 resulting from
elevated CEK (Graph 6).
• H2O2 in Eop stage adds minimal delignification boost which limits D 1 KF reduction.
• Increased level of NaOH to Eop for maintaining 10.0-10.2 pH indicates H2O2
reaction/consumption with recycled COD carryover from D 1 washer(Graph 7). Filtrate recycle
is standard operation for recycling D1 and Eo filtrates on D1 washer showers.
• Effluent color numbers are inconclusive.
• Quality as measured by viscosity and brightness was unchanged by H2O2 addition (Table
5).
• H2O2 addition to pine Eo stage is ineffective, demonstrating no financial opportunity. Future use
is not recommended.
Page 4
3. Results:
Table 1: Hardwood H2O2 Trial Process Summary (averages)
Pre Pre Shwr PB D1 D1 D2
BI BI cond mat D1 D1 H2SO4 mxr I Eo D2 NaOH D2
Period TPD Kno PN mmhos cond 9Pm KF % PH NaOH CEK 9PM gPM ISO
1st q.base 727 6.26 6.30 101.85 593.03 122.30 0.29 1.08 3.36 9.79 1.69 77.19 0.66 86.4
June base 730 6.19 5.65 115.01 426.05 107.43 0.25 0.68 3.17 10.48 1.82 62.66 0.13 86.6
Jul 752 6.12 5.64 60.43 421.26 95.67 0.23 0.74 3.28 10.52 2.05 61.05 0.11 86.7
Aug777 6.69 5.99 101.74 521.20 94.03 0.19 1.07 3.28 10.51 2.69 88.29 0.21 86.9
Set 762 6.31 5.96 156.26 501.98 91.20 0.20 1.01 3.17 10.92 2.70 94.64 0.50 86.4
Oct 764 6.39 6.08 152.98 536.81 101.01 0.22 1.10 3.10 11.71 2.58 101.72 0.96 86.3
July-Sept av 93.6 2.48 81.3
Table 2: Hardwood H2O2 Trial Environmental and Quality Summary (averages)
D1 color Eo color
period TPD #/da x 1000 #/da x 1000 Visc c s D2 ISO
1 st quarter base 726.99 5.42 6.20 16.27 86.44
June base 730.49 5.50 8.69 14.61 86.56
July 751.84 7.32 6.08 13.55 86.74
Aug777.36 7.78 6.75 14.12 86.59
Set 762.48 9.67 5.97 14.68 86.44
Oct 763.76 7.36 7.46 15.07 86.33
July-Sept av 8.3 6.3
Table 3: Hardwood H2O2 Trial Bleach Chemical Usage and Cost Summary (averages)
total# total Ep# total D2# total# C102 NaOH H2O2
6102/T NaOH/T NaOH/T CI02/T/kno $/T $/T $/T Total $/T
1 st quarter base 34.57 17.77 1.20 5.52 18.48 3.86 0.00 36.49
June base 29.34 18.93 0.24 4.74 15.68 2.70 0.00 34.66
July 26.26 18.45 0.19 4.29 14.04 3.80 1.56 34.09
Aug29.55 17.83 0.35 4.42 15.80 3.70 1.56 35.25
Set 30.71 18.89 0.87 4.86 16.41 4.03 1.56 37.04
Oct 33.45 20.22 1.65 5.23 17.88 4.45 1.56 39.99
July-Sept avg I L I $35.46
Table 4: Pine H2O2 Trial Process Summary(averages)
Eo
Lab PO PO Pre BI D1 D1 % D1 D1 mxr NaOH D2 D2
period TPD PN Kno Kno QPM KF acid PH 9pM CEK gpm ISO
list quarter base 643 9.71 10.37 9.73 124.5 0.21 .0.33 3.44 17.7 2.92 127.0 86.2
June base 628 8.99 9.82 9.53 126.5 0.23 0.09 3.28 15.1 2.66 121.6 86.6
July 672 7.99 10.26 10.18 130.3 0.21 0.33 3.33 20.0 3.13 135.7 86.7
Aug685 8.85 10.45 10.13 134.4 0.21 0.31 3.32 20.5 3.62 148.9 86.8
Sept. 690 9.67 9.72 9.34 134.2 0.22 0.28 3.35 21.3 3.36 154.5 86.5
1 609 9.9 33 3.2 14422 86.6Oct 3 6Jul -Se 132.9 37
Page 5
Table 5: Pine H2O2 Trial Environmental and Quality Summary(averages)
D1 color Eo color 3A color
#/day x #/day x #/day x
period TPD 1000 1000 % closure 1000 D2 vise cps D2 ISO
1st quarter base 643 2.04 3.10 78.45 16.91 15.70 86.2
June base 628 0.94 5.84 78.00 16.89 15.96 86.6
July 672 0.92 1.78 89.66 7.57 15.74 86.7
Aug685 1.61 0.39 85.06 9.37 15.22 86.8
Se t. 690 0.73 3.44 81.38 11.77 15.15 86:5
Oct 609 5.2 4.1 64.8 12.7 14.9 86.60
July-Sept av 1.09 1.87 85.2 9.6
Table 6: Pine H2O2 Trial Bleach Chemical Usage and Cost Summary(averages)
total# total#
period CIO2/T NaOH/T C102$/T NaOH$/T H2O2$/T Total $/T
1st quarter base 49.6 36.2 26.50 7.38 0.00 33.88
June base 49.8 31.8 26.60 6.48 0.00 33.08
July 49.4 39.2 26.42 7.99 2.08 36.49
Aug52.1 39.5 27.84 8.04 2.08 37.96
Set 52.4 40.7 27.99 8.29 2.08 38.37
Oct 56.5 33.5 30.20 6.83 0.00 37.03
July-Sept av 37.60
3a. Hardwood Results:
The Hardwood trial operating parameters resulted in the monthly average CEK increasing from a
1.8 baseline to 2.5 trial (Table 1), increasing overall monthly average bleaching costs from
$34.66 to $35.46 respectively (Table 3).
Hardwood trial results are summarized in Tables 1-3 above and Graphs 1-3 in appendix.. Trial
periods are summarized on a monthly basis and shown sequentially on x axis of graphs.
Table 1 shows:
• Is`quarter base period shows high Pre Bleach(PB) mat conductivities, 0.29 KF,
increased bleach chemical usage. This was a period of problematic brownstock washing
operation, which was resolved during March outage.
• D1 trial KFs ranged from 0.19-0.23, down from 0.25-0.29 in base periods preceding trial,
0.226 KF in July trial period being the most effective.
• Trial period showed a 0.2 gpm increase in H2SO4 required to maintain D 1 mixer pH of 3.3.
Page 6
• Kajaani K-nos and and lab PNs increased 6.1-6.7 and 5.6-6.1 respectively during trial
period.
• PB mat conductivity increased from 421 to 537 µmho during trial period. The increased
mat conductivity correlated to increased H2SO2 usage for D1 pH control.
• As the D1 KF was reduced, the CEK increased from 2.05 to 2.7,up from 1.7-1.8 in base
periods (graph 1).
• D2 C1O2 charge increased from 61-95 gpm as CEK increased(graph 2).
• NaOH for Ep control to 10.2-10.5 pH increased about 1 gpm.NaOH for D2 pH control
increased 0.4-0.8 gpm as D2 C1O2 charge increased (Graph 3).
• H2O2 results were favorable at 0.23 KF, 6.1 k-no, 421 µmho mat conductivity. At
increased K-nos and washer losses, H2O2 lost delignification efficiency.
• Adjusting DI KF up to 0.222 in Oct. trial period did not show favorable results seen in
July trial period. Higher PO K-nos from seasonal cooking changes,unsteady operation
resulting from recovery liquor inventories and poor D 1 washer operation were
contributors to diminished results.
Table 2 shows:
• D1 effluent color increased to 7,300-9,700/day during trial period. Ep effluent color was
steady in a 6,000-7,500#/day range and 3A initially dropped to 7,600#/day, gradually
increasing to to 12,000-12,500#/day.
• D2 final viscosity initially dropped to 13.6 cps, but remained in the 14-15 cps range
during most of the trial.
• Final D2 brightness was above 86.0 ISO for trial period.
Table 3 shows:
• Initial July trial period showed favorable cost results of$0.57/T savings. This eroded to
$0.60-$3.90/T loss.
• pH control to Ep and D2 stages accounted for$1.10-$1.65/T of additional chemical cost.
3b. Hardwood Discussion
The No. 1 hardwood bleach line showed the most potential for the H2O2 trial plan. The hardwood D1
stage was operating with KFs in the 0.25-0.29 range with E Stage CEK of< 2.0. Targeting a H2O2 trial
D 1 KF of 0.2 would result in a Ep CEK of< 2.5. The increased D2 C1O2 usage resulting from the stated
rise in CEK would be more than offset by the C1O2 reduction in D1, enough to justify the H2O2
operating costs.
Once H2O2 flow was established at 0.3% addition rate, the D1 KF was gradually reduced to the 0.2
level. The bleach control KF curves were updated and control bias adjusted after about a week at each
KF level.
Page 7
This strategy worked for July, at a 0.22 KF, when PO Kajaani K-nos/lab PNs averaged 6.115.65 and
fiberline operation was steady.
During the Aug. and Sept. periods, the 0.2 KF level was established, the PB K-nos increased, and PB
washer losses were higher, resulting in an Ep CEK> 2.5 (Graph 1). At these CEK levels, the D2 C1O2
levels increased to levels greater than the D1 reduction (Graph 2). At D2 C1O2 flow levels > 90 gpm, D2
NaOH flow pH control also increased, adding to the bleach chemical costs.
In the Oct. period, the D1 KF was increased to the 0.22 level of July. The PO K-nos and washer losses
were 6.4 and 537 µmhos respectively, notably higher than the July period. These process shifts resulting
from seasonal cooking changes and unsteady recovery operation. Operating problems with the D1
washer were also encountered. With these process changes, the H2O2 addition could not keep the Ep
CEK<2.5.
From these observations it is concluded that the Ep stage H2O2 reinforcement is most effective in a
narrow operating range of K-nos, with steady state operation. Any deviation in these or other front end
operating parameters reduces the H2O2 delignification efficiency.
3c. Pine Results
The Pine trial operating parameters resulted in the monthly average CEK increasing from a 2.7
baseline to 3.4 trial (Table 4), increasing overall monthly average bleaching costs from$33.08 to
$37.60 respectively (Table 6).
i
Pine trial results are summarized in Tables-4-6 above and Graphs 5-7 in appendix. Trial periods
are summarized on a monthly basis and shown sequentially on x axis of graphs.
Table 4 shows:
• lS`quarter base period shows very good bleach chemical usage, with KF averaging 0.21,
which would be very difficult to improve upon with H2O2.
• Trial period D1 KFs averaged 0.21-0.22, reduced from 0.23 base period.
• D1 KF reduction resulted in CEK increase to 3.1-3.6 range (Graph 5).
• Elevated CEK increased D2 C1O2 flow to 136-155 gpm range (Graph 6).
• Lab PO PNs tracked significantly lower than Kajaani PO K-nos for July-Aug trial periods. CEKs
for same periods do not indicate overbleaching.
• Elevating Bo pH target to 10.0-10.2 range increased NaOH usage 5-6 gpm.
• Oct. period results without H2O2 inconclusive due to annual outage and start up.
Page 8
Table 5 shows:
• No significant change in D1 effluent color. Eo effluent color dropped to 1780-390#/day
range in July Aug trial periods while % closure was>80% during the entire trial period.
3A color initially dropped to 7,600#/day, gradually increasing to to 12,000-12,500#/day.
• D2 final viscosity was> 15 cps and D2 final brightness> 86.5 ISO during entire trial
period.
Table 6 shows:
• Bleach chemical costs were negative for the entire trial period., ranging$3.00-$5.25/T
over June base period.
• pH control to Eo stage accounted for$1.50-$1.80/T of additional chemical cost.
3d. Pine Discussion
The No. 2 pine bleach line showed limited potential for the H2O2 trial plan. The pine D 1 stage, was
operating with KFs in the 0.21-0.23 range with Eo Stage CEK in the 2.5-2.9 range. Targeting a H202
trial D 1 KF of 0.2 would result in an Eop CEK 3.0-3.25 range. The increased D2 C1O2 usage resulting
from the stated rise in CEK would be more than offset by the C1O2 reduction in D1. Given this KF
reduction is small,the resulting C1O2 savings would be hard pressed to justify the H2O2 operating costs.
Once H2O2 flow was established at 0.4% addition rate, the D1 KF was reduced to the 0.2 level. The
bleach control KF curves were updated and control bias adjusted after about a week at each KF level.
This strategy showed the best results for July, at a 0.21 KF,-when PO Kajaani K-nos/lab PNs averaged
10.3/8.0. This discrepancy raised concern, test procedures and Kajaani bias were checked. The bleaching
response reacted more in line with the K-nos.
Results for all three trial periods saw Eop CEK levels mostly> 3.5, which results in high D2 C1O2 usage.
The Eop stage pH control showed a substantial increase in NaOH to maintain the optimum > 10.0 pH
for H2O2 bleaching. This suggest the H202 is being consumed by the D1 washer recycled COD. Spot
checks of the D 1 washer discharge pulp showed COD levels of 70 kg/T.
From these observations it is concluded that the Eop stage H202 reinforcement is not effective. H202 in
the Eop is a consumed by high levels of recycled COD from D1 washer. The Pine bleach line already
runs well at respectable 0.21-0.23 D1 KF levels. Target D1 KF below 0.21 results in a disproportionate
increase in Eo CEK, which the applied H202 cannot control.
Page 9
5.Appendix.
Graph 1: Hwd D1 Kappa Factor vs CEK Graph 2: Hardwood D1 Kappa CEK/D1 and D2
C1O2 charge relationship
2.80
2.60 120 — ----
2.40 110 .�
2.20 100 ..
Y 2.00 a 90
0 80
1.80 N
1.60 O 70 —D1 GO'l
1.40 U 60 �_D2 Q02
1.20 50
1.00 40
0.255 0.225 0.194 0.200 0.221 1.82 2.05 2.69 2.70 2.58
Kappa Factor (KF) CEK
Graph 3: Hwd D2 C1O2 gpm vs D2 NaOH
1.20
1.00
E
a 0.80
o,
0 0.60
m
Z 0.40
fV
0.20
0.00
62.66 61.05 88.29 94.64 101.72
D2 C1O2 gpm
Page 10
Graph 5: Pine D1 Kappa Factor(KF)w CEK- Graph 6:DI and D2 C102 charge/CEK
3.8 relabonship
3.6 160.0
3�4
155.0
32 150.0
3.0 E 145.0
Ui 0.
2.8 0
- 140.0
2.6 C4
135.0
2.4
130.0
2.2 GPM
125�O �Dlclw
GM
2.0 0.226 0.208 0.211 0.222 120.0
GPM 102 2.7 3.1 3.6 3.4
Kappa factor (KF)
CEK
Graph 7: Pine Eo%NaOH pH control
22.0
20.0
0 18.0
LLI
0 16.0
514.0
m
Z 12.0
10.0
June base July Aug Sept.
Trial Period
Statistical Overview of Peroxide Application on Softwood and Hardwood
Fiberlines for Color at the Canton Mill
Canton, North Carolina
3rd Quarter 2011
Nick McCracken-Water Compliance Coordinator,Evergreen Packaging Canton Mill
December 2011
The full-scale trial for the application of peroxide to the fiberlines at the Canton Mill began on
June 22, 2011 for the pine fiberline and ran through September 27, 2011. The hardwood
fiberline trial began on June 25, 2011 and ran through October 27, 2011. Color data from June
through September on both fiberlines were used for the statistical analysis.
The third quarter color data of 2010 were used for comparative purposes against the 2011 trial
data because of the close similarities in pulp production and Permanganate Numbers (PN) prior
to bleaching on both fiberlines. All data analyzed were checked against final averages from this
time period and with a two-test series (Two sample T-test&ANOVA) for statistical
significance. All statistically significant findings were of 95% or greater confidence. Measured
color streams included: Primary Influent, Secondary Effluent, Acid Sewer, Pine Fiberline Bleach
Plant, Hardwood Fiberline Bleach Plant, #3A Sewer and Evaporator Contaminated Condensates.
Averages for the Primary Influent& Secondary Effluent streams were lower than the third
quarter of 2010 data and were found to be statistically significant. Other averages that were
below the third quarter comparison data and also found to be statistically significant were the
#3A Sewer and Evaporator Contaminated Condensate. The Acid Sewer color average was lower
during the trial period but the difference was not statistically significant.
There was no reduction in the pine fiberline bleach plant combined color average. In fact, the
overall average color number was higher than the color average observed in 2010. The pine Dl
filtrate stream was the only one, from both fiberlines, to have a lower color average during the
trial. This average was also statistically significant. The pine Eo filtrate stream was not
statistically significant and demonstrated a higher color average than in 2010.
The hardwood fiberline bleach plant combined color average increased and this increase was
statistically significant. The overall average color number was higher than the color average
observed in 2010. Both the Dl and Eo filtrate color averages were higher in comparison to the
2010 data and both were found to be statistically significant.
Full-scale application of peroxide to the hardwood and pine fiberlines during 3rd Quarter 2011
was not beneficial to Secondary Effluent color at the Canton Mill. Both fiberline bleach plants
experienced higher color averages when compared to the third quarter data of 2010. Other
outside processes in the mill drove the color performance observed in the Primary Influent and
Secondary Effluent averages.
Attachment—power point presentation,peroxide trial analysis of color
Canton Mill Full-Scale Trial of
Enhanced Extraction with
Peroxide on Eo stages (EoP)
Analysis of Color
3rd Quarter 2011
Nick McCracken and Color Team
Comparison
• Used 3Q 2010 vs. 3Q 2011 Trial Period
— Pulp production numbers comparable
- 3Q 2010 — 1446 avg tons/cal day
• Trial — 1455 avg tons/cal day
Pre-02 PN #s comparable
• 3Q 2010 Hwd — 9.6
• Trial (Hwd) — 9.7
• 3Q 2010 Pine'— 17.6
• Trial (Pine)- 17.6
z •
PI & SE Color Performance
Primary Influent 8 Secondary Effluent Color Comparison
30 2010".Trial
45,000
40,000
35,000 -
30,000
w 25.000 .-
a i
c 20,000 -- ---
15,000 "'..
10,000 -
5,000
830PI Is Tnal R u 30 Sk_ ■Trial S,
3
PI & SE Stats
• There is a statistical significance using a
T-test and ANOVA analysis
• Both tests showed a >95% confidence
• PI difference of 6720 Ibs/day based on
average
• SE difference of 5476 Ibs/day based on
average
4
Bleach Plant Numbers
• Filtrate Numbers Compared:
— Hwd D1
— Pine D1
— Hwd Eo
— Pine Eo
— Acid Sewer (PD1+PD2+HD1+HD2)
— 3A Sewer (PEo+HEo+Excess Evap Condensates)
— Hwd Total Bleach Plant Color
— Pine Total Bleach Plant Color
5
D1 Filtrate Colors
D7 Filtrate Color Numbers
3012010 vs.Trial Period
9,000
8,000
7,000
6,000
a 5,000
4,000
3,000
2,000
1,000
0
■3QkMd ■Trial KW ■3Q Pine ■Trial Pine
8
D 1 Stats
• Hwd D1 shows a statistical significance
— >95% Confidence
• Hwd D1 average was 1367 Ibs/day higher
than 3Q 2010
• Pine D1 shows a statistical significance
— >95% Confidence
• Pine D1 average was 1273 Ibs/day less
than 3Q 2010
7
Eo Filtrate Colors
Eo Filtrate Color Numbers
3012010 vs.Trial Period
7,000
6.000
5.000
2 4,000
$� 3.000
2,000
1.000
0
03O RW ■Tdal Hwd 03Q Pim ■Trlel Phr
B
Eo Filtrate Colors
HM EO 8 Plne EO Color Nombers lo,PomxlGx T6.1 E din9 9127l11
12
10
0
Alec . 4011 11,� <ec 4"�N, •a^,�.� .�s'�.^ °c��� ��R.
—I �h•En—li "W Eul�IImY(EW Ee)
9
Eo Stats
• Hwd Eo shows a statistical significance
— > 95% Confidence
• Hwd Eo average is 769 Ibs/day higher
than 3Q 2010
• Pine Eo shows no statistical significance
• Pine Eo average is 493 Ibs/day higher
than 3Q 2010
10
Acid Sewer Color
(PD1+PD2+HD1+HD2)
Acid Sewer Color Numbers
30 2010 vs.Trial Period
7.500
7,000
6,500
T
A
6,000
a_
5,600
5,000
4,500
, •3Q10 ■TdN
11
Acid Sewer Stats
• Acid Sewer showed no statistical
significance
• Acid Sewer average was 201 Ibs/day less
than 3Q 2010
12
Hardwood Fiberline Total Bleach
Plant Color
Hwd Fibedine Total Bleach Plant Color
3Q 2010 vs.Trial
14,000
13,500
13.000 - —
a 12,500
a
11,500
11,000
10,500
■3Q10■Ttlel
13
Hwd Bleach Plant Stats
Hwd Total Bleach Plant Color shows a
statistical significance
>95% Confidence
• Hwd TBP Color average is 2071 Ibs/day
higher than 3Q 2010
14
Pine Fiberline Total Bleach Plant
Color
Pine Fiberline Total Bleach Plant Color(AS+Eo Filtrate)
3Q 2010 vs.Trial
8,700
8,650
8,600
T
ay 8.550
a_
8.500
8.450
8,400
■3Q10■Trial
15
Pine Bleach Plant Stats
• Pine Total Bleach Plant Color shows no
statistical significance
• Pine TBP Color average is 147 Ibs/day
higher than 3Q 2010
16
Contaminated Condensate Color
Condensate Color Numbers
3Q 2010 vs.Trial
2,500
2,W0
1,500
1,000
500
0
i■3010 Caianr�eo�Trlel Contaminated
17
Contaminated Condensate Stats
• Contaminated Condensate does show a
statistically significant difference
— >95% Confidence
• Color concentration (ppm)
• Overall loading (Ibs/day)
• Color concentration was 58.7 ppm lower
than 3Q 2010
• Color loading was 1228 Ibs/day lower than
3Q 2010
18
3A Sewer Color
(PEo+HEo+Excess Evap Cond)
3A Sewer Color Numbers
30 2010 vs.Trial
11,500
11,000
10,500
10,000 :..
9.500
$_ 9,000
8,500
8,000
7,500
7,000
330FC a Tnx
14
3A Sewer Stats
• 3A Sewer color does show a statistical
significance
— 95% Confidence
— 2 tests ran; T-test & ANOVA
• 3A Sewer color average is 1437 Ibs/day
lower than 3Q 2010
20
2071
136] Trial affected operations 69
14]
1 ] 493
(1437) (201)
(12281
Non Trial mill operations
Recovery,Kilns,aSW,Paper BBoaM
(6720) (5476)
� cao,m�maee
cow o.ae.0 21
Conclusions
• Both PI & SE were SS and their avg went down
vs. 3Q 2010
• Other color streams looked at that were
statistically significant:
— 3 the avg went down (PD1 & 3A & Evap Cond)
— 3 the avg went up (HD1 , HEo & HBP)
• Other stream averages that were not SS:
— 1 the avg went down (Acid Sewer)
— 2 the avg went up (PEo & PBP)
22
Conclusions cont.
• Is there a color benefit from Peroxide?
— No-Bleach Plant color increased
• 5 out of 6 color monitoring points in the trial affected area went up
• Total bleaching costs increased$0.80 per ton on Hardwood and
$4.52 per ton on Pine
• Seasonal and other process variation contributed to color
performance that was not associated with this trial
• Exceptional evaporator performance and overall BMP
closure drove PI and SE color performance
— First time since CMO of 2003 that both sets of evaporators were
cleaned at the same time
— Both fiberlines cleaned and jetted washer during CMO
— 'Exceptional color awareness and preparations around CMO
23
A%=TL
Pulp & Paper
Evergreen Packaging Bleaching
Canton, NC
Report: No.2011-054 Date issued:
Date: August 3, 2011 Author: Pamela O'Leary
Evergreen Packaging
Attention: William Miller
Contact:Andritz Inc.
Division: Pruyn's Island Technical Center
Project Manager: Michael Kingsley
13 Pruyn's Island Drive
Glens Falls, NY 12801
Phone: (518)745-2999
Fax: (518)745-2971
E-mail: Michael.kingsley@andritz.com
www.andritz.com
Confidential document.All rights reserved.No duplication or disclosure to third partiers permitted Wthout the written consent of ANDRITZ AG.
AMRMTL
Pulp a Paper
Summary
Evergreen Packaging supplied Andritz with mill oxygen delignified softwood and hardwood pulps
for laboratory bleaching trials. We were to compare the effect on effluent color and fully bleached
strength properties by changing the current Eo/E stages to Eop/Ep and pressurized Pht stages.
Softwood was bleached using Do-Eo-D, Do-Eop-D and Do-Pht- D to a target 86% ISO brightness.
Hardwood was bleached to the same brightness target using Do-E-D, Do-Ep-I) and Do-Pht-D.
Observations
• Mill softwood had a kappa number of 14.2 and viscosity of 14.3 mPa•s.
• Mill hardwood had a kappa number of 6.8 and viscosity of 13.8 mPa•s.
Bleaching Chemicals Con sum tion Summary
Bleaching Sequence C1O2 H2O2 Final ISO Final
Consumed Consumed Brightness Viscosity
K /ADMT K /ADMT % mpa•s
Softwood Do-Eo-D 25.2 - 86.1 11.2 (cor-
rected
Do-Eo -D 23.3 4.5 86.2 10.8
Do-Pht-D 21.4 5.4 86.4 10.7
Hardwood Do-E-D 17.5 -- 86.1 10.7
Do-E -D 12.6 2.7 86.3 10.8
Do-Ph,-D 8.8 4.5 1 86.5 11.3
Tear and Tensile Index@ 400 CSF of Fully Bleached Pulps
Tensile Index Tear Index
LIMS ID Descriptive ID (N•m/g)at 400 (mN•m'/g) at 400
CSF CSF
124576 Softwood Do-Eo-D 84.93 8.68
124582 Do-PHT-D 81.93 8.51
124579 Do-Eo -D 83.81 8.41
124572 Hardwood Do-E-I) 66.26 8.15
124745 Do-PHT-D 70.49 9.02
124818 1 Do-E -D 68.98 8.80
ConfldenW doc M.Atl rights reserved.No�plKaUon w diaclmure to thM pa t penrxlted rvikio t Ne wMlen cor N WANDRRZ AG. Page 2 of 11
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Pulp a Paper
Experimental
Standard Operating Procedures
Procedure Description
PITC-134 100% Chlorine Dioxide Substitution
PITC- B8 Chlorine Dioxide Bleaching
PITC-136 Alkaline Extraction
PITC- B6 Oxidative Alkaline Extraction w/ eroxide
Tappi T525 om-92 Diffuse Brightness
TappIT230 Capillary Viscosity
TappiT248 PFI Beatin of Wood Pulp
ITappiT236 Kappa Number
NCASI TB#253 Color in Effluent
ITappIT227 Canadian Standard Freeness
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Pulp a Paper
Test Results
Table 1. Softwood Do-E-D Bleaching
Sample Mill Post 02 Softwood
Sample ID 124558
Kappa number 14.2
Viscosity, mPa s 14.3
ISO Brightness, % 35.2
Do Stage: 150eF. 40 min., 10% cons.
Sample ID 124574
Kappa Factor 0.24
C1O2, % 1.29
H2SO4, % 0.35
Final pH 2.8
Consumed C1O2, % 1.29
ISO Brightness, % 51.9
Color, C.U. 1850
Eo Stage: 1750F, 60 min..35 psi 0 psi. 10 min.. 10% cons.
Sample ID 124575
NaOH, % 0.9
Final pH 11.0
Kappa Number 3.2
Viscosity, mPa s 13.8
ISO Brightness, % 58.2
Color, C.U. 2390
D Stage: 165eF, 240 min., 10% cons.
Sample ID 124576
CIO2, % 1.0 1.2 1.4
NaOH, % 0.45 0.54 0.6
Final pH 4.2 4.1 3.6
CIO2 Consumed, % 1.0 1.197 1.396
ISO Brightness, % 84.6 85.1 86.1
Color, C.U. -- -- 59
Viscosity, mPa•s 11.2 (corrected)
Gpnfgent dppu t All rights reserved.No dug'Ice6on a d,sc ..Ip t Id pa ti.permitted wN ,ft vm1 m.,&ANDRIR AG. Page 4 M I I
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Pulp a Paper
Table 2. Softwood Do-Eop-D Bleachng
Sample Mill Post 02 Softwood
Sample ID 124558
Kappa number 14.2
Viscosity, mPa-s 14.3
ISO Brightness, % 35.2
Do Stage: 150°F, 40 min., 10%, cons.
Sample ID 124577
Kappa Factor 0.2
CIO2, % 1.08
H2SO4, % 0.49
Final pH 2.9
Consumed C1O2, % 1.08
ISO Brightness, %e 49.0
Color, C.U. 2125
Eop Stage: 175eF, 60 min.,35 psi. psi ' 0 psi. 10 min., 10%cons.
Sample ID 124578
NaOH, % 1.1
H2O2, % 0.5
Final pH 11.0
Kappa Number 3.2
H2O2 Consumed, % 0.5
Viscosity, mPa-s 12.9
ISO Brightness, % 64.3
Color, C.U. 2045
D Stage: 165°F, 240 min., 10% cons.
Sample ID 124579
C1O2, % 1.0 1.2 1.4
NaOH, % 0.45 0.54 0.6
Final pH 4.4 3.8 4.0
C1O2 Consumed, % 1.0 1.2 1.4
ISO Brightness, % 84.8 85.6 86.2
Color, C.U. --- --- 58
Viscosity, mPa-s --- --- 10.8
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Pulp s Paper
Table 3. Softwood Do-Pht-D Bleaching
Sample Mill Post 02 Softwood
Sample ID 124558
Kappa number 14.2
Viscosity, mPa-s 14.3
ISO Brightness, % 35.2
Do Stage: 150eF, 40 min., 10% cons.
Sample ID 124580
Kappa Factor 0.2
CIO2, % 1.08
H2SO4, % 0.49
Final pH 2.9
Consumed C1O2, % 1.08
ISO Brightness, % 48.8
Color, C.U. 2125
PNT Stage: 2000F, 60 min., 100 psi. 15 min. 10%, cons.
Sample ID 124581
NaOH, % 1.4
H2O2, % 0.6
Final pH 11.1
Kappa Number 2.8
Viscosity, mPa s 12.3
ISO Brightness, % 67.5
Color, C.U. 1640
D Stage: 165°F. 240 min., 10% cons.
Sample ID 124582
CIO2, % 0.8 1.0 1.2
NaOH, % 0.30 0.40 0.50
Final pH 3.9 4.0 4.0
CIO2 Consumed, % 0.8 1.0 1.2
ISO Brightness, % 84.5 85.6 86.4
Color, C.U. -- -- 71
Viscosity, mPa s 10.7
ConfMenoal tloc Ml.All nghls reserved.No d ,,N Uon or die mum to tl pertlers pertMled w t ft rriam consent of ANDRITZ AG. Page 6 a t l
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Table 4. Hardwood Do-E-D Bleaching
Sample Mill Post 02 Hardwood
Sample ID 124655
Kappa number 6.8
Viscosity, mPa-s 13.8
ISO Brightness, % 44.1
Do Stage: 1500F. 40 min., 10%cons.
Sample ID 124570
Kappa Factor 0.26
C1O2, % 0.67
H2SO4, % 0.7
Final pH 2.5
Consumed C1O2, % 0.67
ISO Brightness, % 67.4
Color, C.U. 685
E Stage: 175°F. 60 min., 10% cons.
Sample ID 124571
NaOH, % 0.9
Final pH 11
Kappa Number 2.7
Viscosity, mPa•s 13.1
ISO Brightness, % 68.4
Color, C.U. 570
D Stage: 165T. 160 min., 10% cons.
Sample ID 124572
CIOZ, % 1.0 1.2 1.4
NaOH, % 0.40 0.48 0.56
Final pH
C1O2 Consumed, % 0.997 1.190 1.394
ISO Brightness, % 85.5 86.1 86.7
Color, C.U. -- 27 --
Viscosity, mPa•s 10.7
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Table 5. Hardwood Do-Pn-D Bleaching
Sample Mill Post 02 Hardwood
Sample ID 124655
Kappa number 6.8
Viscosity, mPa s 13.8
ISO Brightness, % 44.1
Do Stage: 1500F. 40 min., 10%cons.
Sample ID 124743
Kappa Factor 0.21
CIO2, % 0.54
H2SO1, % 0.7
Final pH 2.7
Consumed CIO2, % 0.54
ISO Brightness, % 64.7
Color, C.U. 373
PHT Stage: 2000F, 60 min., 100 psi. 15 min. 10% cons.
Sample ID 124744
NaOH, % 1.3
H2O2, % 0.5
MgSO4, % 0.1
H2O2 Consumed % 0.5
Final pH 11.3
Kappa Number 2.7
Viscosity, mPa•s 11.6
ISO Brightness, % 79.4
Color, C.U. 210
D Stage: 1650F. 160 min.. 10% cons.
Sample ID 124745
CIO2, % 0.2 0.4 0.6
H2SO4, % 0.09 0.01 --
NaOH, % -- -- 0.05
Final pH 4.2 4.0 3.4
CIO2 Consumed, % 0.2 0.4 0.6
ISO Brightness, % 84.9 86.7 87.8
Color, C.U. -- 52 --
Viscosity, mPa s 11.3
Cwfitlenri tlocumml.All noM resmv W tl pfratbn or,A,tl m to Ihvtl px m pem,6b4 xet,out tl xeitlen a &t RITZ AG. page 8 a}11
AMR/TL
Pulp a Paper
Table 6. Hardwood Do-Ep-D Bleaching
Sample Mill Post 02 Hardwood
Sample ID 124655
Kappa number 6.8
Viscosity, mPa s 13.8
ISO Brightness, % 44.1
Do Stage: 150°F, 40 min.. 10% cons.
Sample ID 124746
Kappa Factor 0.21
CIOz % 0.54
H2SO4, % 0.7
Final pH 2.7
Consumed CIO2, % 0.54
ISO Brightness, % 65.0
Color, C.U. 345
Ep Stage: 175eF, 60min., 10% cons.
Sample ID 124747
NaOH, % 1.0
H2O2, % 0.3
Final pH 11.1
H2O2 Consumed, % 0.3
Kappa Number 2.7
Viscosity, mPa-s 12.0
ISO Brightness, % 74.8
Color, C.U. 365
D Stage: 165°F. 160 min.. 10% cons.
Sample ID 124818
CI02, % 0.6 0.8
NaOH, % 0.04 0.24
Final pH 4.4 3.8
CI02 Consumed, % 0.6 0.8
ISO Brightness, % 85.7 86.3
Color, C.U. -- 32
Viscosity, mPa s 10.8
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Table 7. Physical Strength Properties
PH Cond Burst Tensile Tear Tensile Elongation
Descriptive CSF Wt Bulk Index Index Index T.E.A.U/m2) Stiffness
LIMS ID ID (# (mL) (gm) (cm'/g) (kPa•m'/g) (N-m/g) (mN-m'/g) (kNlm) (mm)
revs
124572 0 557 6.50 1.87 1.34 29.37 9.06 26.68 335.7 1.90
0.5 528 6.51 1.66 2.53 48.94 9.31 61.65 435.3 2.69
HW, Do-E-D 1.0 483 6.39 1.56 3.35 60.40 8.44 82.13 470.0 3.02
2.0 356 6.38 1.45 4.25 69.36 8.00 105.58 495.4 3.43
3.0 246 6.35 1.37 4.71 76.39 7.20 119.32 519.1 3.54
124576 0 691 6.63 1.76 2.40 36.64 22.11 58.16 356.5 3.17
0.5 660 6.56 1.56 4.25 60.34 12.96 89.49 473.6 3.23
SW, Do-Eo-D 2.5 520 6.58 1.42 5.30 81.19 9.69 108.98 576.5 3.00
5.0 350 6.28 1.39 5.83 86.49 8.26 118.57 568.7 3.22
7.5 235 6.38 1.35 6.16 88.63 8.31 129.55 587.9 3.37
124579 0 678 6.44 1.82 2.33 34.93 20.95 49.45 344.1 2.90
0.5 632 6.71 1.57 4.38 64.61 12.07 114.04 493.9 3.77
SW,Do-Eop-D 2.5 408 6.46 1.39 5.70 83.65 8.44 133.23 558.1 3.62
5.0 172 6.33 1.32 5.94 88.41 7.55 133.06 579.5 3.49
7.5 88 6.28 1.27 6.32 93.91 7.14 140.25 589.7 3.50
124582 0 696 6.48 1.86 2.22 33.44 23.08 44.76 332.5 2.73
0.5 652 6.44 1.58 4.07 62.12 13.11 95.83 463.4 3.43
SW, Do-PHT-D 2.5 461 6.46 1.41 5.39 79.90 8.80 120.16 543.8 3.40
5.0 201 6.33 1.31 5.91 88.56 7.58 130.04 576.0 3.39
7.5 91 6.37 1.28 6.23 96.06 7.31 148.79 614.6 3.56
124745 0 593 6.54 1.9 1.24 29.30 8.12 27.57 334.0 1.93
0.5 554 6.49 1.66 2.45 49.52 9.57 63.72 435.2 2.76
HW, Do-PHT-D 1.0 515 6.42 1.56 3.13 59.43 9.78 79.92 472.7 2.97
2.0 384 6.44 1.44 4.24 72.03 8.91 110.08 516.4 3.38
3.0 269 6.34 1.37 4.62 76.72 8.11 117.64 513.6 3.47
124818 0 556 6.46 1.90 1.39 30.64 8.54 25.90 341.7 1.79
0.5 536 6.47 1.65 2.60 51.95 9.40 66.86 445.5 2.76
HW, Do-Ep-D 1.0 484 6.46 1.53 3.31 61.04 9.18 82.53 478.8 2.97
2.0 377 6.52 1.44 4.08 71.15 8.69 110.91 522.4 3.40
3.0 260 6.38 1.36 4.45 72.30 8.05 111.83 509.0 3.42
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Miscellaneous Information
All samples included in this report will be held in cold storage for three months after issuance of the
report. At that time, the samples will be discarded without notice. If there is a need to retain sam-
ples longer than the three-month grace period, please contact PITC.
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a
r
Laboratory Study of Likely Effects of
Oxidatively Intensifying the Extraction
Stages at Evergreen Packaging's
Canton, NC Mill
Progress Report
T om 7 l�Ic '-on ,
u
h a ,,�
Febr aK 109 201.2 (Draft 2)
Confidential
Executive Summary
This report describes a study undertaken to study and document the effects of oxidatively reinforcing the
Canton mill's extraction stages. The effect on effluent color was of particular interest; effects on chemical
consumption and bleached pulp physical properties were also measured.
Mill oxygen delignified softwood and hardwood pulps were subjected to laboratory bleaching trials. In the
case of the softwood pulp trials, existing(EO) stage conditions were compared with conditions chosen to
simulate(EPO) and(PO) stages.The(EPO) stage was simulated by adding 0.5%hydrogen peroxide. The
(PO) stage(sometimes referred to as a pressurized peroxide or PHT stage) was simulated by increasing the
temperature, oxygen pressure and peroxide charge. In the case of the hardwood pulp trials, the existing E
stage conditions were compared with conditions chosen to simulate(EP) and(PO) stages. The(EP) stage
was simulated by adding 0.3% peroxide. The PO stage was simulated by inargising the peroxide charge,
pressurizing with oxygen and raising the temperature. In both cases the chlbijiie dioxide charge in the Do
stage was decreased slightly and the chlorine dioxide charge in the D . take was adjusted to reach the
desired target brightness. Effects on the color of all bleaching stag iefflu°nts were monitored. Effects on
bleaching chemical consumption and bleached pulp physical proper ies w re als\oo measured.
In the softwood case, adding peroxide to the(EO) stage result d n almost no�d1drease in total effluent
color. Converting the(EO) stage to a (PO) stage decreas d ttZtotal color by 11 o Tot 1 chlorine dioxide
consumption was reduced by 5.6— 10 lb/ton (0128 0Z%on pulp).
`�. N'
In the hardwood case, adding peroxide resulted in a 429/e rMuctio" or. Converting[h' E stage to a
o!lyw
(PO) stage gave a 50% reduction. Total chlorine dioxide c�b> ptrC was reduced by 12— 161b/ton(0.6—
0.8% on pulp)
With a few exceptions, effects on the physic lip�'oche of both pulpgkpes were generally small or
nonexistent.The exceptions were increases in elangaho tensile energky absorption of the softwood
pulps and increases in maximum tearing resista'c stren��o�e, az(w�nod pulps, as well as increases in
the tensile strength at which tna lum�teazin r il^',SCce s dried.
The results suggest that there little to be gained b u° plementing the softwood pulp extraction stage
modifications studied here. In the case of the hardwod ulp, however, adding peroxide to the extraction
stage has the potential to' uAtantially decrease the col rj;of the pulp bleaching effluent and significantly
decrease chlorine dioxide cobsutnpti&.
Introcfull
n
The Canmploys the �-NoO)D�_cching sequence to produce bleached softwood and hardwood
pulps. The trul tcommissioned a a oratory�study to predict the effects of intensifying the alkali extraction
stages in the ..aching sequences of�both softwood and hardwood pulps. In the case of softwood,this
amounted to con the(EO)' tage to either an (EPO) stage or a high-temperature pressurized peroxide
nr
stage, here denoted yFZP,O). In�the c�ase of hardwood the study assessed the effects of converting the E
stage to a peroxide reinforcedi!exraction stage(EP) or a(PO) stage. These changes can be expected to
reduce the color of the mill effluent.
Post-oxygen mill pulps were the starting materials for the study. The kappa number and viscosity of the
softwood pulp were, respectively, 14.2 and 14.3 mPa.s.The kappa number of the hardwood pulp was 6.8
and its viscosity was 13.8 mPa.s.
After each stage, the pulps were characterized by suitable measurements (kappa number, brightness and/or
viscosity, depending on the stage) and the color of the effluent from each of the last three stages was
measured. In addition, fully bleached samples were subjected to laboratory refining and the physical
properties of the refined pulps were measured.
The experiments were performed at the Pruyn's Island Technical Center of Andritz Inc. The raw data and
details of the experimental procedures used maybe found in their report.'
2
Results and Discussion
Multistage Bleaching
Tables I and 2 contain the results of the multistage bleaching experiments that were performed on the
softwood and hardwood pulps, respectively.
Effluent Color
Figures land 2 illustrate the effects of reinforcing the extraction stage on the color of the bleaching stage
effluents. Figure 1 shows that, in the softwood case, adding peroxide to an(EO) stage to convert it to an
(EPO) stage resulted in almost no decrease in total color, measured as the sum of the three individual
effluent color values. Increasing the temperature, oxygen pressure and per a charge, i.e. converting the
(EO) stage to a(PO) stage,decreased the total color from 4299 units to nits (an I I%reduction). In
both the(EPO)and(PO)cases, the attendant decreases in Do kappa CIO2 charge)caused slight
increases in the color of the Do effluent.
6000
5000
4299 4228
4000 3836 ❑D1
0 ■E
Y
.0
3000 ■DO
0
0
U
2000 b low-,
1000
0
(EO) (EPO) (PO)
Figure 1. Effects of extraction stage reinforcement on softwood bleaching effluent color
In the hardwood case there were somewhat greater effects of reinforcing the extraction stage, as Figure 2
shows. Adding peroxide decreased the total color(again measured as the sum of the individual stage
effluent color values)from 1282 to 742 units(a 42%reduction). Increasing the temperature, oxygen
pressure and peroxide charge, i.e. converting the(EO)stage to a(PO) stage, further decreased the total
color to 635 units (a 50%reduction relative to the value obtained when the extraction stage employed
neither oxygen nor peroxide).
3
Table 1. Results of Bleaching Softwood Pulps
Type of Extraction Stage (EO) (EPO) (PO)
Unbleached kappa number 14.2 14 2 14.2
Viscosity, mPa•s 14.3 J4.13Y 14.3
ISO Brightness, % 35.2 = 352 35.2
Do Stage: 150°F,40 min., 10% cons.
C102,% 1.29 1.08 1.08
H2SO4, % 0.35 0.49 0.49
Final pH 2.8 2.9 2.9
Residual g/L as C12 0 0 0
ISO Brightness, % 51.9 - 49.0 49.0
Filtrate color, C.U. 1850 2125 2125
Extraction Stage: 60 min., 10% cons.
NaOH, % 1.4
Temperature, T 175� 175 200
02 Pressure(0/10/15/60 min.), psig ( 5101010) (3'5/0/0/0) (100/100/0/0)
H2O2, % 0 0.5 0.6
Final pH 1.0 11.0 11.1
Kappa Number 3.2 3.2 2.8
Viscosity, mPa•s 1 .8 12.9 12.3
ISO Brightness, % 58.2 64.3 67.5
Filtrate color, C.U. 2390 2045 1640
i
D, Stage: 165°F,240 min , 10% cons.
C102, % .2 1.4 1.0 1.2 1.4 0.8 1.0 1.2
NaOH,%p 0.4 0.54 0.6 0.45 0.54 0.6 0.3 0.4 0.5
Final pH 4. 4.1 3.6 4.4 3.8 4.0 3.9 4.0 4.0
Residual C102, g/L 0 0.003 0.004 0 0. 0 0 0 0
Total Sequence C102,% 2.29 2.49 2.69 2.08 2.28 2.48 1.88 2.08 2.28
Viscosity, mPa•s -- -- 11.2 -- -- 10.8 -- -- 10.7
ISO Brightness, % 84.6 85.1 86.1 84.8 85.6 86.2 84.5 85.6 86.4
Filtrate color, C.U. -- -- 59 -- -- 58 -- -- 71
4
Table 2. Results of Bleaching Hardwood Pulps
Type of Extraction Stage E (EP) (PO)
Unbleached kappa number 6.8 A13.8
6.8
Viscosity, mPa•s 13.8 13.8
ISO Brightness, % 44.1 44.1
Do Stage: 150°F,40 min., 10% cons.
C102,% 0.67 . 0.54
H2SO4, % 0.7 0.7 0.7
Final pH 2.5 2.7 2.7
Residual g/L as C12 0 (3445
0
ISO Brightness, % 67.4 64.7
Filtrate color,C.U. 685 373
Extraction Stage: 60 min., 10% cons.
NaOH, % 1.3
Temperature, °F 175 200
02 Pressure(0/10/15/60 min.),psig (0/0/ 0 (0 /0) (100/100/0/0)
H2O2, % = 0 0.3 0.5
Final pH 11.0 11:1 11.3
Kappa Number 2.7 2.7 2.7
Viscosity, mPa•s 12.0 11.6
ISO Brightness, % 68 4 74.8 79.4
Filtrate color,C.U. 570 365 210
D, Stage: 165°F,240 in' ., 10% cons. Ir
C102. % 1.0 1.2 1.4 0.6 0.8 0.2 0.4 0.6
NaOH/H2SO4,% 0. 0/0 0.48/0 0.56/0 0.04/0 0.24/0 0/0.09 0/0.01 0.0510
Final pH -- -- 4.4 3.8 4.2 4.0 3.4
Residual C102, g/L 0003 0.010 0.006 0' 0 0 0 0
Total Sequence C102,% 1.67 1.87 2.07 1.14 1.34 0.74 0.94 1.14
Viscosity, mPa•s -- 10.7 -- 10.8 -- 11.3 --
ISO Brightness, % 85.5 86.1 86.7 85.7 86.3 84.5 85.6 86.4
Filtrate color, C.U. -- 27 -- -- 32 - 52
5
1600
1400
1282
1200
D1
rn 1000
c ® E
800 742
o 635 1-1 Do
v 600
400
200 - ,
0
E Ireinfor
P) PO)
Figure 2. Effects of extraction stage ent on hardwood bleaching effluent color
The results s ,Figure. I and 2 ,uggest that there is little to be gained by implementing the
softwood traction e modifications studied here. In the case of the hardwood pulp, however,
adding de to the extr n aLtge has the potential to substantially decrease the color of the
hardw bleaching of l pent.
In regard to t ffluent color reductions, it should be noted that the reductions achieved in actual mill
practice may be ly different. When individual stage effluents are combined the color that results is
not the sum of the t ual stage effluents. One reason for this is that the color of extraction stage
effluents is pH depen their color is decreased when they are acidified. Adding acidic D stage
effluents to extraction stage effluents decreases their pH and therefore also decreases their color.This
effect may be offset to some extent by a pH-dependent increase in the color of the D stage effluents.
Chemical Consumption
Figure 3 illustrates the favorable effect of reinforcing the extraction stage on total C102 consumption
when bleaching softwood pulp. At a foal brightness level of 86.0,and under the conditions of these
experiments, adding 10 lb of peroxide per ton of pulp to the(EO) stage may be expected to result in a
reduction in total C102 consumption of 5.6 lb/ton(0.28%on pulp). Further intensifying the extraction
stage by increasing the peroxide charge to 121b/ton, increasing the temperature and pressurizing with
oxygen may be expected to result in a further reduction of 4.4 lb/ton(0.22% on pulp). In this case the
6
total reduction in C102 consumption would therefore be 10 lb/ton(0.5%on pulp)relative to the(EO)
case, where peroxide was not used.
87.0
Z:(EPO)
86:5
r 85.5
85.0 ;
84.5 •
,
84.0
1.6 1.8 2.0 2.2 2.4 2.6 2.8
- Total CI02(Do+D, ,0.
Figure 3. Final brightness S. to O consum do ; softwood pulp.
Figure 4 shows the correspo for the dw d pulp:Addmg 6 lb of peroxide per ton of pulp
to the extraction stage resulte m a red cti n in tot 1 02 consumption of 12 lb/ton of pulp (0.6% on
pulp.. Adding high-pressure oxygen an m ceasing t e eroxide charge to 101b/ton while also increasing
the temperature resulted t a rther r uc 'on of 41b t n 0.2% on pulp). In this case the total reduction
in C102 consumption woul t e f re a 16 /ton 0. n pulp)relative to the case where neither
oxygen nor peroxide was us
87.0
86.5
86.0 ----------------- ---- --------------- ----------
N
d i • i
C
t 85.5 '
,
m � I
9 i i ♦E
85.0 I I •(EP)
i
84.5
84.0 �
0.4 0.6 0.8 1.0 1.2 ,1 /11 6/ 1.8 2.0 2.2 2 4
Total CIO"(Do'+Dl),%
Figure 4.Final brightness vs. total C102 consumption; hardwood pulp.
Physical Properties of Bleache Pul s
Softwood Pulps
results in T ble 3 sho s that tht s udied•exxt a ti`n to a modifications had, with one
Inspection of the es ✓ 4 r g
possible exception, virtua . no effect n t e physical properties of bleached softwood pulp. Figure 5
demonstrates the lack o�n}' effects on he relationship between handsheet density and tensile strength
and Figure 6 shows thair�,y�11 three a traction types�ga e pulps with the same tear-tensile characteristic.
The possible exception is a effect n elon atlan d its associated effect on tensile energy absorption, as
shown in Figures-7-and�8.
Ta�b7e�3. h s Properties of Bleached Softwood Pulps
Tensile Burst Tear Tensile
Density Elongation
Pulp ID PR CSF Index Index Index T.E.A. Q/m2) Softness lnd
(#revsx 103) (ML) (gtZ) (H'u✓8) (kPa ml/&) (mN•m'/e) (kNMB)
(EO) \0.0 691 0.568 36.64 2.40 22.11 58.16 3.17 356.5
Os 66D 0.64I 60.34 4.25 1296 89.49 3.23 473.6
2.5 \N520� 0.704 91.19 5.30 9.69 108.98 3.00 5765
5.0 350 0.719 86.49 5.83 826 118.57 3.22 568.7
7.5235 0.741 88.63 6.16 1 8.31 129.55 1 3.37 587.9
(EPO) 0.0 678 0.549 34.93 2.33 20.95 49.45 2.90 344.1
0.5 632 0.637 64.61 4.38 12.07 114.04 3.77 493.9
2.5 408 0.719 83.65 5.70 8.44 133.23 3.62 558.1
5.0 172 0.758 88.41 5.94 7.55 133.06 3.49 5795
7.5 88 0.787 93.91 6.32 7.14 140.25 3.50 589.7
(PO) 0.0 696 0.538 33.44 222 23.08 44.76 2.73 3325
0.5 652 0.633 62.12 4.07 13.11 95.83 3.43 463.4
2.5 461 0.709 79.90 5.39 8.80 120.16 3.40 543.8
5.0 201 0.763 88.56 5.91 7.58 130.01 3.39 576.0
75 91 0.781 96.06 1 6.23 1 7.31 1 148.79 1 3.56 1 614.E
8
120
"0 M(E )
i •
80
Z
a f
� 60
m
N �
40
20
0
0.45 - 0.50 0.55 0.60 0.65 0.00.75 0.80 .85
Density,g/c s
Figure 5.Softwood pulp to it index vs.sheet density
30
25
L 'z •(EO)
•(EPO)
N
E, 2 ■(PO)
z
E
axi 15
v
y 0 •
5
i
Zti,i
20 40 60 80 100 120
Tensile Index, N.m/g
Figure 6.Softwood pulp tearing resistance vs. tensile index
9
4.00
3.80
3.60
E 3.40
E 3.20
c
° 3.00
A
rn
0 2.80 •(EO)
m 2.60 •(EPO)
■ Po
2.40
2.20
2.00 I u
0 20 40' 60 . 80 100 20
Tensile Index/. ' /g
Figure 7.Softwood pulp lingation vs.TR ile Index .,
180
160
r
140
12
E 100 a/
a
w"80`
F I�
60 •(Eo)
•(EPO)
4O ■(PO)
20
0 N
0v 20 40 - 60 80 100 120
Tensile Index,N.m/g
Figure 8.Softwood pulp tensile energy absorption vs. tensile index
Hardwood Pulps
The results in Table 4 indicate that the studied extraction stage modifications had virtually no effect on
the physical properties of bleached hardwood pulp, with one exception. Figure 9 demonstrates the lack of
any effects on the relationship between handsheet density and tensile strength. The exception to the above
statement is illustrated by Figure 10, which shows that intensification of the extraction stage increases the
10
maximum tearing resistance that can be achieved by refining and also increases the tensile strength at
which the maximum tearing resistance is achieved.
Table 4.Physical Properties of Bleached Hardwood Pulps
Tensile Burst Tear Tensile
DensPulp ID PH CSF ) (
Index Index index T.E.A. (/m2) Elonga-)ion
( Stiffness Inde
(#)evs x 103) (ML) B/emnm (N-Mg) (kPa-rnVg) (mN.01g) mm) (kNMg)
E 0.0 557 0535 29.37 1.34 9.06 26.68 1.90 335.7
0.5 528 0.602 48.94 2.53 931 61.65 2.69 435.3
1.0 483 0.641 60.40 3.35 8.44 / /6�82.13 3.02 470.0
2.0 356 0.690 69.36 4.25 8.00 ! /10559 3.43 495.4
3.0 246 0.730 1 76.39 4.71 1 7.2 :11: a / 11932 1 3.54 519.1
(EP) 0.0 556 0.526 30.64 139 Q 5�¢^ 25.90 1.79 341.7
0.5 536 0.606 51.95 2.60 ) :40 \ 66gZ\Z.88�6 2.76 445.5
9.18
2.0 377 0.694 71.15 ,,4/0 � 8.69 I10..9� 3.40 522.4
3.0 260 0.735 72.30 .F4:451 8.05 111.83 3.42 509.0
(PO) J3.0
593 0526 29.30 <` ' 124 8.1y 27.57 \,'°L93 341.7
554 0.602 49.52 \T45 57 63.72 287§� 445.5
515 0.641 59.43 3,1 79.92 2.97 478.8
384 '0.694 72.03 4.24\ 91 110.08 3.38 522.4
269 1 0.730 ,.76,j2 4.62 \\„ S.11 117.64 3.47 509.0
90' \ \:
80 •E
♦(EP)
■(PO)
E 7U® •
E D
X 60 y
9 �
C �
d 5
N
C '
~ 40
30 '/•
20
0.45V.50 0.55 0.60 0.65 0.70 0.75 0.80
Density,g/cc
Figure 9. Hardwood pulp tensile index vs. sheet density
11
10
■
10 ■
•
9
a
E 9 •
z
E
x" 6
d
v
c
`m 6 E
7
7 iir
; �,
6
20 30 40 50 60� 70 80 `901N�
Tensile TAU; m/g
_ ,!Iiii
Figure 10.Hardwood pulp tearing resistance vs,
tensile index
Summary and Conclusions Nil y
Mill oxygen-delignified softwood and hardwood i ulps were-subjecte st6laboratory bleaching trials to
evaluate the effects of potential^changes to the c ndt�ons t Ikal extraction stage. In the case of the
i � s iin°
softwood pulp trials, existi�g O}slag\e conditto s,ilwer compare ith conditions chosen to simulate
(EPO) and(PO) stages�he(EPO) stage�las simul te�by adding 0.5% hydrogen peroxide. The(PO)
stage(sometimes referred tons a pressurized peroxidejor,Pm stage)was simulated by increasing the
temperature, oxygen press u e and peroxtd�charge.IInTh ase of the hardwood pulp trials, the existing E .
stage conditions er ce o npared�vith conditions chosen.to simulate(EP) and(PO) stages. The(EP) stage
was simulated y'ts g;03%peroxide. The PO stage was simulated by increasing the peroxide charge,
pressurizing w t oxygen'andlraisinglthe temperature. In both cases the chlorine dioxide charge in the Do
stage wa(d., reased slightir2fi'd the chl\n dioxide charge in the D) stage was adjusted to reach the
desired tar�e,,t� b * fitness. Effe�CQs5 the color of all bleaching stage effluents were monitored. Effects on
bleaching chd �al consumptto a d bleached pulp physical properties were also measured.
In the softwood caa��e;+addmg pe�� zide to an(EO) stage to convert it to an(EPO) stage resulted in almost
no decrease in totals Al,oe meas�ur as the sum of the three individual effluent color values. Increasing
QQ ;:uu
the temperature, oxyge�i�t Ppresssi nd peroxide charge, i.e. converting the(EO) stage to a(PO)stage,
decreased the total color (Tin 4299 units to 3836 units (an 11% reduction). In both the(EPO) and(PO)
cases, the attendant decreases in Do kappa factor(CIOZ charge) caused a slight increase in the color of the
Do efffluent.
In the hardwood case there were somewhat greater effects on effluent color. Adding peroxide decreased
the total color(again measured as the sum of the individual stage effluent color values) from 1282 to 742
units (a 42%reduction). Converting the(EO) stage to a(PO) stage further decreased the total color to 635
units (a 50%reduction relative to the value obtained when the extraction stage employed neither oxygen
nor peroxide).
12
Reinforcing the extraction stages decreased total chlorine dioxide consumption by as much as 10 lb/ton
(0.5% on pulp) in the case of softwood pulp and by as much as 16 lb/ton(0.8% on pulp) in the case of the
hardwood pulp.
With a few exceptions, effects on the physical properties of both pulp types were generally small or
nonexistent.The exceptions were increases in elongation and tensile energy absorption of the softwood
pulps and increases in maximum tearing resistance strength and in the tensile strength at which the
maximum tearing resistance is achieved.
In general, the results suggest that there is little to be gained by implementing the softwood pulp
extraction stage modifications studied here. In the case of the hardwood pulp,however, adding peroxide
to the extraction stage has the potential to substantially decrease the color f the pulp bleaching effluent
and significantly decrease chlorine dioxide consumption.
'
' Report:No.2011-054, Pruyn's Island Technical Center;'Andritz Inc. (August 3,
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Andritz—Alstrom 02 Delig Studies
CONFIDENTIAL BUSINESS INFORMATION
6
PRUYN'S ISLANID TECHNICAL CENTER
REPORT 2001-068 PART 1.
LABORATORY CK AND LO-SOLIDS COOKING WITH O-Do-Eop-D BLEACHING
SEQUENCES ON SOFTWOOD FURNISH FROM
BLUE RIDGE PAPER,BLUE RIDGE,NC
Part 1. Softwood Results
Part 2. Hardwood Results
TO:
Allen Turner
Jay Miele
Issued:
December 6, 2001
Issued by: Scott Daley and Keith Crofut
Tel.(518)745-2980
Fax(518)745-2971
Allen Turner Pruyn'sIsland Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Summary
Blue Ridge Paper of Blue Ridge, NC requested the sales department of Andritz-Ahlstrom to
investigate alternate methods of pulping and bleaching that would reduce their waste products
and improve the quality of their hardwood and softwood paper products. As a result, the Pruyn's
Island Technical Center produced Conventional Kraft (CK) and Lo-Solids® (LS) brownstock,
oxygen delignified and fully bleached pulps for strength testing and comparison to current mill
pulp samples supplied by the mill in June of 2001.
Currently, the mill batch cooks-both softwood and hardwood pulp. The bleaching sequence is O-
Do-Eo-D with hydrogen peroxide addition in the E stage when the softwood is produced. The
fully bleached lab pulps were produced using the current mill sequences and an alternative
hardwood sequence O-A-ZDo-Eo-D. Thd brightness targets were softwood ISO 88% and
hardwood ISO 89%. Throughout the lab bleaching, the effluent colour was monitored and the
metals content of the softwood bleach filtrates was determined. The mill supplied a MRP filtrate
sample (sample ID 2001-002005) for use in all lab softwood Do stages. The mill also supplied
unscreened brownstock, oxygen delignified, and fully bleached pulps.
This part of Report 2001-068 deals with the softwood pulp production and bleaching only. For
details concerning the hardwood see PITC lab report 2001-068 Part 2.
Observations
• Laboratory conventional kraft pulp kappa numbers ranged from 18.7 to 37.2 The viscosities
ranged from 20.0 to 31.2. (Viscosity for Cook S3136 was not measured as the kappa number
was greater than 35).The total brownstock yields ranged from 42.3 to 45.9 % on wood.
• Laboratory Lo-Solids° pulps ranged in kappa number from 22.3 to 31.1. The viscosities of
the lab LS pulps ranged from 30.2 to 41.7 mPa•s. The brownstock total yields ranged from
42.3 to 43.3 (total yield for cook AL773 was not measured as the kappa was not in the
targeted range).
• The bleaching results are summarized below:
Brightness Viscosity C102Charge H20,Charge
Pulp and Se4uence %ISO mPa•s Kg/BDMT Kg/BDMT
Softwood
Mill BS Lab O-Do-Eop-D 88.0 14.3 18.0 5.0
Mill Oz Lab Do Eop-D 88A 13.6 18.8 5.0
Mill Fully Bleached 87.6 15.7 --- ---
Lab CK Lab O-Do-Eop-D 87.9 13.4 17.0 5.0
Lab LS Lab O-Do-Eop-D 89.5 17.1 16.3 5.0
• The strength results demonstrate Lab Lo-Solids pulps are superior in tear index versus tensile
index when compared to mill pulps. (see Table 1-10 and Figure 1-5)
c,ma=cnu an65etsivgslmushaWucal SettingsWemprary ltnmt FiloMMU001-068 P I SW Final Repa2tlac
�njyn4
Allen Turner Pruyn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Experimental
The mill requested that the MRP filtrate be added to all softwood Do stages to simulate mill
conditions.
Standard OQerating Procedures
PTTC-1`27 Lo-Solids®Cooking Simulation(27 Liter Circulating Digester)
PITC-P6 Wood Chip Size and Thickness Distributions
PTTC-1`7 Wood Chip Moisture Free Fraction
PTTC-P8 General Wood Chip Handling
PTTC-P9 Pulp Moisture Free Fraction
PTTC-P10 Pulp Yield
PTTC-PI l Pulp Defiberin ,Centrifuge Washin ,and Pin-shredding
PTTC-P24 Conventional Kraft Cook(5 Liter Swing Digester)
TappiT205 om-88 Forming Handsheets for Physical Tests of Pulp
Tappi T248cm-85 Laboratory Beating of Pulp(PFI Mill Method)
Tappi T227om-94 Freeness of Pulp
Tappi 7220s 96 Physical Testing of Pulp Handsheets
Tappi T403om-91 Bursting Strenpth of Paper
Ta i T414om-88 Internal Tearing Resistance of Paper
Tappi T494om-88 Tensile Breaking Properties of Paper and Paperboard
PrfC-14 Dirt Count
TAPPI T236 Kappa#of pulp
SCAN N33 Residual hydroxide(hydroxide ion content)of black liquor
SCAN N2:88 AA,EA,TA of white/green liquor-potentiornetric titration
TAPPIMO Viscosity of pulp(capillary viscosity method)
HUT Method 23.2.1995 Hexenuronic acid content of Kraft pulps
PTTC-B3 Oxygen Deli nification
PTTC-B4 Chlorination
PTTC-115 Acid Hydrolysis(Ahl-stage)
PTTC-B6 Alkaline Extraction
PTTC-138 Chlorine dioxide bleaching
PTTC-B11 Low&medium consistency ozone deli nification in fluidizing mixer
PTTC-B 12 Hydrogen eroxide bleaching
PTTC-B19 Pulp washing
CPPA H.5 Colour of pulp mill effluents
PTTC-A18 Carbohydrate content of wood or pulp by HPAEC-PAD
Standard Methods 3111 Metals.b FAA
Tappi T525 om-92 ISO brightness(pad formation and testing)
C:a)onmaau and SenugA=,halydnnl ScUingsU mparuy Inu=ReAOLM0001.068 Part I SW Final Repomdoc 2
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G4ON E Iit IIN 1 11
Allen Turner Pruyn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Results
Table 1-A.Mill Pulp and Filtrate Results
Sample Login Kappa Viscosity Brightness Rejects Tappi Dirt
Sample Description ID Plumber (diPa•s) %ISO %on Arealppm
pulp (w.041)imi)
Softwoods5=an44d
Brownstock 2001-001999 --- ---- ---- 0.35 ---
Lab Screened 2001-002000 21.5 22.0 29.3 -- 419.66
Brownstock
Oxygen Delignified 2001-002003 ---- ---- 33.6 276.09
Fully Bleached 2001-002004 ---- 15.7 87.6 ---- 2.06
MRP Filtrate 2001-002005
Metals Content,mg1L Ca=35.88 Fe=0.88 Mg=9.64 Mn=3.52
Colour,C.U. 890
Part 1. Softwood Results.
The following list of tables and figures summarizes the results of the work performed on the
softwood furnish and the softwood mill and lab pulps.
Table 1-1. Softwood Chip Size and Thickness Classifications. J
Table 1-2.Laboratory Conventional Kraft(CK) Cooking of Softwood Ty
Table 1-3.Laboratory Lo-Solids® (LS) Cooking of Softwood
Table 1-4. Laboratory O-Do-Eop-D Bleaching of Mill Softwood Brownstock Pulp
Table 1-5. Laboratory Do-Eop-D Bleaching of Mill.Softwood Oxygen Pulp -
Table 1-6.Laboratory O-Do-Eop-D Bleaching of Lab Softwood CK Pulp
Table 1=7.Laboratory O-Do-Eop-D Bleaching of Lab Softwood IS Pulp
Table 1-8.Laboratory Two Stage Oxygen Delignifications of Mill Softwood-Brownstock Pulp
Table 1-9. Strength Results for Selected Mill and Lab Softwood Pulps
Table 1-10.Tear Index and Tensile Index at 400 CSF of Selected Softwood Pulps
Figure 1-1. Total Yield versus Kappa Number for Lab Softwood Cooking
Figure 1-2. Laboratory Cooking Response for Softwood Furnish
Figure 1-3. Viscosity versus Kappa Number for Lab Softwood Cooking
Figure 1-4.EA Consumed versus Kappa Number for Lab Softwood Cooking
Figure 1-5. Tear Index versus Tensile Index for Selected Mill and Lab Softwood Pulps.
Figure 1-6.Tensile Index versus PFI Revolutions for Selected Mill and Lab Softwood Pulps
Figure 1-7. Strength Results for Mill Softwood Brownstock Pulp
Figure 1-8. Strength Results for Mill Softwood Oxygen Pulp
Figure 1-9. Strength Results for Mill Softwood Fully Bleached Pulp
C.ANWmenu and SC ingsVnarsA4WAe41 Sellingau mpalM Inwrct r"0LK41a00l-M P+n I SW My R4pomdW 3
I T I A L
Allen Turner Pruyn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part I
Alpheretta,GA December 6,2001
Figure 1-10. Strength Results for Mill Softwood Brownstock Lab O-Do-Eop-D Bleached Pulp
Figure 1-11. Strength Results for Lab Softwood Lo-Solids®Brownstock Pulp
Figure'l-12. Strength Results for Lab Softwood Lo-Solids®Oxygen Pulp
Figure'1-13. Strength Results for Lab Softwood Lo-Solids®O-Do-Eop-D Pulp
Table 1-1. Softwood Chip Size and Thickness Classifications
Chip Size Fraction Chip Thickness Fraction
(mm) (%) (mm) (%)
0-3 0.1 0-2 1.3
3-7 2.5 2-4 25.2
7- 12.7 22.3 4-6 36.1
12.7-25.4 49.9 6-8 21.8
25.4-45 21.9 8- 10 7.7
45 and greater 3.3 10 and greater 7.8
C.Mmmenu end SeuingAmme0elda 1 Seldnga\Tempmary 1n iHcAOMV001-03 Pan 1 SW Final Repen.dm 4
• Allen Turner Pruyn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Table 1-2.Laboratory Conventional Kraft (CK) Cooking of Softwood
Cook ID S3136 S5251 S6068 S3137 S5252 S6069 S3140 S3148
Cook Type CK CK CK CK CK CK CK CK
Date of Cook 08.03-01 08-03-01 08-03-01 08-06-01 08-06-01 08-06-01 08.09-01 09-05-01
Furnish Southern Pine 2001-001990
Wood Charge(g od) 750 750 750 750 750 750 750 750
Steaming:
Temperature(nC) - 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0
Time(min) 15.0 15.0 15.0 15.0 15.0 15.0 15.0 15.0
Impregnation:
EA Charge(%on wood NaOH) 19.2 19.2 19.2 21.6 21.6 21.6 21.6 21.6
Liquor Sulfidity(%AA) 27.0 27.0 27.0 27.0 27.0 27.0 27.0 31.2
AQ(%on wood) - - - - - - - -
1IW Ratio(L/1tg) 3.5 3.5 3.5 3.5 3-5 3.5 3.5 3.5
Temperature('C) 110.0 110.0 110.0 110.0 110.0 110.0 110.0 110.0
Time to Temperature(min) 15.0 15.0 15.0 15.0 15.0 15.0 15.0 15.0
Time at Temperature(min) 30.0 30.0 30.0 30.0 30.0 30.0 30.0 30.0
Co-current:
Temperature(°C) 165.3 169.5 170.0 166.4 169.5 163.8 166A 166.4
Time to Temperature(min) 15.0 15.0 15.0 15.0 15.0 15.0 15.0 15.0
Time at Temperature(min) 88.0 91.0 102.0 111.0 107.0 104.0 112.0 109.0
Final Cooking Results:
Residual pH 13.1 13.0 13.0 13.2 13.2 13.2 13.1 13.1
Residual EA(g/L NaOH) l(ki 8.3 7.0 12A 12.0 13.9 12.8 12.7
EA Consumed(%on wood NaOH) .#r 15.7 16.3 16.8 17.3 17.4 10.7 17.1 17.2
H-Factor 960 1430 1680 1320 1670 1040 1320 1290
Kappa Number 37.2 27.5 23.7 21.7 19.7 29.9 21.7 22.8
Viscosity(mPa•s) NM 30.6 27.0 24.5 20.0 31.2 25.4 24.5
Brownstock Total Yield(% on wood) 45.9 44.6 44.1 42.9 42.3 44.9 42.8 43.3
Total Rejects(%on wood) 0.91 0.76 1.05 0.11 0.39 0.49 0.30 0.09
Screened Yield(% on wood) 45.0 43.9 43.0 42.8 41.9 44.4 42.5 43.2
Knots>13 mm(%on wood) 0.61 0.63 °0:94,j 0.03 0.35 0.42 0.23 0.03
'CK=Conventional Kraft Process bAQ=Anthraquinone `SODA=Soda Process
CD"umenn89d SetlivgsWarsfilNaal geNngATemponry Intoner PoeAOLICd\2001-068 Put i SW Final ReportdW 5
Allen Turner Prayn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA - December 6,2001
Table 1-3. Laboratory Lo-Solids® (LS) Cooking of Softwood
Cook ID AL773 AL775 AL776
Date of Cook 2001-08-14 2001.08-15 2001-08-21
Wood Charge(g od) 3500 3500 3500
Steaming:
Temperature(°C) 100.0 100:0 100.0
Time(min) 15 15 15
Impregnation:
EA Charge(%on wood NaOH) 10.0 10.0 10.0
Liquor EA(g/L NaOH) 28.6 28.6 28.6
Liquor Sulfidity(%AA) 27.8 27.8 27.8
L/W Ratio(L/kg) 3.5 3.5 3.5
Temperature(°C) 110.0 110.0 110.0
Time to Temperature(min) 15 15 15
,
Time at Temperature(min) 30 30 30
Pressure at Temperature(kPa) 923 939 911
Residual pH 12.9 13.0 . 13.0
Residual EA(g/L NaOH) 7.8 7.8 7.8
EA Consumed(%on wood NaOH) 7.3 7.3 7.3
Displacement 1:
Temperature(°C) 162.4 164.5 -165.6
Time to Temperature(min) 15 15 15
Time at Temperature(min) 45 45 45
Pressure at Temperature(kPa) 1411 939 1349
EA Charge(%d on wood NaOH) 8.0 8.0 8.0
Liquor EA(glL.NaOH) 87.6 87.6 87.6
L/W Ratio(lAg) 3.5 3.5 3.5
Fresh Liquor Flow(mUmin) 53.0 53.0 53.0
Fresh Liquor Flow Time(min) 60 60 ` 60
Displaced Liquor Flow(mUmin) 53.0 53.0 53.0
Displaced Liquor Flow Time(min) 60 60 60
Residual Liquor pH 12.9 13.1 13.2
Residual Liquor EA(g/LNaOH) 1o.8 10.5 lu
Displaced Liquor pH 12.9 13.0 13.0
Displaced Liquor Residual EA(g/L NaOH) 6.9 6.8 7.0
EA Consumed(%on wood NaOH) 6.3 6.4 6.4
C1Docum and SviinpM haMLaal Settinrs\Temponrylnt FaeetOLa4V001.06a Pan I SW Finalftomda 6
-� ll I A
Allen Turner Pruyn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Table 1-3 (continued). Laboratory Lo-Solids® (LS)Cooking of Softwood
Cook ID AL773 AL775 AL776
Co-current 1:
Temperature(°C) 162.4 164.5 165.6
Time at Temperature(min) 60 60 60
Pressure at Temperature(kPa) 1120 1135 1278
L/W Ratio(IJkg) 3.5 3.5 3.5
Residual pH 12.9 12.9 13.0
Residual EA(g/L NaOH) 7.0 6.5 6.5
EA Consumed (%on wood NaOH) 1.3 1.4 1.4
Displacement2:
Temperature(°C) 162.4 164.5 165.6
Time at Temperature(min) 180 180 180
EA Charge(%on wood NaOH) 0.9 6.9 6.9
Liquor EA(g/L NaOH), 44.7 44.7 44.7
Liquor Sulfidity(%AA) 27.8 27.8 27.8
L/W Ratio(IJkg) 3.5 3.5 3.5
Fresh Liquor Flow(mL/min) 30.0 30.0 30.0
Fresh Liquor Flow Time(min) 180 180 180
Displaced Liquor Flow(mL/min) 30.0 30.0 30.0
Displaced Liquor Flow Time(min) 180 180 180
Residual Liquor pH 13.0 13.1 13.1
Residual Liquor EA(g/L NaOH) 14.0 13.6 13.4
Displaced Liquor pH 13.0 13.1 13.1
Displaced Liquor Residual EA (g/L NaOH) 10.2 9.6 9.9
EA Consumed(%on wood NaOH) 2.9 2.9 3.0
Final Cooking Results:
H-Factor 2400 2870 3150
Kappa Number 31.1 25.4 22.3
Viscosity(mpa•s) 41.7 35.2 30.2
Viscosity/Kappa Number Ratio 1.3 1.4 1.4
Total Yield(%n on wood) - NM 43.3 42.3
Total Rejects(%on wood) NM 0.17 0.11
Screened Yield(%on wood) NM 43.1 42.2
Knots>13 mm(%on wood) NM 0.10 0.08
Total EA Consumed(%on wood NaOH) 17.8 18.0 18.0
CADmmenu cnd Se&gAnmaba1r%Lma15e1ingATempam7 Imemel MakOLM0001-068 Pan I SW Fwl Repan.da
Allen Turner Pruyn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-069 Part I
Alpheretta,GA December 6,2001
Table 1-4. Laboratory O-Do-Eop-D Bleaching of Mill Softwood Brownstock Pulp
Sample ID Mill Brownstock 2001-002000
Kappa number 21.5
Viscosity,mPa-s 22.0
Brightness,%ISO 29.3
Bleaching Sequence: O-Do-Eop-D
O-Stage: 60 min. 90eC.80 psi 10% consistencv
Sample ID 2001-00 2530
NaOH,% 1.6
Final pH 11.5
Kappa number 12.6
Viscosity, mPa-s 16.3
Brightness,%ISO 34.1
Filtrate Colour,C.U. 5330
Filtrate Metals,mg/1- Ca=35.8 Fe=0.17 Mg=1.60 Mn=0.70
D,o-Stage:50 min 60°C mill filtrate added back to 10 % consistency
Kappa Factor 0.25 0•25
C102 charge,% 0.96 1.20
Mill Filtrate Colour,C.U. 890 890
Final pH 2.3 2.0
Consumed C102, % 0.96 1.20
Brightness, %ISO 49.4 54.6
Filtrate Colour,C.U. -- 980
Filtrate Metals,mg/L --- Ca=128.24 Fe=1.90 Mg=38.12 Mn=15.10
Eop-Stage•75 min 77°C 40 nsi.10%a consistency
Sample ID 2001-00 2785 2852
NaOH charge, %n 1.3 1.3
H2O2,charge,% 0.3 0.5
Final pH 11.5 11.7
Consumed H2O2,% 0.3 0.5
Kappa number 2.7 2.1
Viscosity,mPa•s 15.3 14.8
Brightness,%ISO 65.2 71.6
Filtrate Colour,C.U. --- 1170
Filtrate Metals,mg/L --- Ca=4.49 Fe=0.30 Mg=1.72 Mn=0.40
D-State:240 min. 740C.10 % consistencv
Sample ID 2001-00 2853
C102 charge,% 0.5 0.6 0.7
NaOH,% 0.1 0.13 0.18
H2SO4, % - --- --
Final pH 3.5 3.5 3.2
Consumed C102, % 0.48 0.57 0.65
Viscosity,mPa-s - 14.3 --
Brightness,%ISO 87.2 88.0 88.5
Filtrate Colour,C.U. --- 52 ---
Filtrate Metals,mg/L Ca=6A8 Fe=0.15 Mg--1.20 Mn--0.43
Tappi Dirt Aredppm(>.o.wmm'). 23.99
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Allen Turner Pruyn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta, GA December 6,2001
Table 1-5. Laboratory Do-Eop-D Bleaching of Mill Softwood Oxygen Pulp
Sample ID Mill Oxygen Delignified 2001-002003
Kappa number 13.5
Viscosity,mPa•s 16.1
Brightness,%ISO 33.6
Bleaching Sequence: Do-Eop-D
Dn-Stage:50 min..600C.mill filtrate added back to 10 % consistency
Kappa Factor 0.20 0.25
CI02 charge,% 1.03 1.28
Mill Filtrate Colour,C.U. 890 890
Final pH 2.8 2.2
Consumed CI02, % 1.03 1.28
Brightness, %ISO 49.9 55.6
Filtrate Colour,C.U. No Sample 1070
Filtrate Metals,mg/L Ca=174.7 Fe=2.2] Mg=38.28 Mn=14.68 Ca=173.84 Fe=2.31 Mg=40.28 Mn=15A2
Eop-Stage:75 min.,770C.40 psi.10% consistency
Sample ID 2001-00 2721 2832
NaOH charge, % 1.3 1.4
H2O2,charge, % 0.3 0.5
Final pH 11.5 11.7
Consumed H2O2, % 0.3 0.5 .
Kappa number 2.6 2.0
Viscosity,mPa•s 14.5 13.9
Brightness, %ISO 66.4 71.9
Filtrate Colour,CU 1295
Filtrate Metals,mg/L Ca=8.42 Fe=0.31 Mg=1.56 Mn=0.64 Ca=6.94 Fe=0.29 Mg=1.58 Mn=0.50
D-Stage:240 min.,740C,10 %e consistency
Sample ID 2001-00 2723 2833
C102 charge, % 0.4 0.5 0.6 0.7 0.5 0.6 0.7 0.8
NaOH,% 0.08 0.25 0.19 0.32 0.05 0.11 0.17 0.20
H2SO4,% 0..06 0.59 - --- - ---
Final pH 3.5 4.4 3.8 4.5 3.3 3.4 3.8 3.9
Consumed 002, % 0.39 0.45 0.58 0.66 0.49 0.55 0.66 0.75
Viscosity,mPa•s -- - -- 13.6 - --
Brightness, %ISO 83.5 86.5 87.3 87.1 87.6 88A 89.0 89.1
Filtrate Colour,CU --- -- --- --- 31 --- --
Filtrate Metals, mg/L --- Ca=16.73 Fe=0.27 Mg=3.70 Mn=0.67.
Tappi Dirt Areatppm(>.0.o4mm')
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Allen Turner Pruyn'sIsland Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Table 1-6. Laboratory O-Do-Eop-D Bleaching of Lab Softwood CK Pulp
Sample ID Lab CK Brownstock S3137+S3140+S3148 (2001.00402+002698)
Kappa number 21.6
Viscosity,mPa•s 24.6
Brightness, %ISO 32.5
Bleaching Sequence: O-Do-Eop-D
O-Stage: 60 min.,90°C,80 osi 10% consistency
Sample ID 2001-00 2561
NaOH, % 1.6
Final pH 11.3
Kappa number 12.6
Viscosity,mPa•s 19.2
Brightness, %ISO 37.3
Filtrate Colour,CU 4330
Filtrate Metals,mg/L Ca=17.22 Fe=0.23 Mg=1.62 Mn=0.34
Do-Stage:50 min..600C,mill filtrate added back to 10 % consistency
Kappa Factor 0.25
CI02 charge,% 1.20
Mill Filtrate Colour,C.U. 890
Final pH 1.9
Consumed C102,% 1.20
Brightness,%ISO 55.5
Filtrate Colour,CU 1720
Filtrate Metals,mg/L Ca=72.10 Fe=3.19 Mg=24.92 Mn=6.92
Eop-Stage:75 tnin..77°C.40 ositdl0% consistence
Sample ID 2001-00 2903
NaOH charge,90 1.3
H2O2,charge,% 0.5
Final pH 11.5
Consumed H2O2,% 0.3
Kappa number 2.22
Viscosity,mPa•s 13.5
Brightness,%ISO 72.3
Filtrate Colour,CU 1280
Filtrate Metals,mg/L Ca=3.06 Fe=0.30 Mg=0.88 Mn=0.13
D-Stage:240 min..74°C.10 % consistency
Sample ID 2001-00 2904
C102 charge,% 0.4 0.5 0.6
NaOH,% 0.05 0.08 0.10
H2SO4,% _-
Final pH 3.1 3.0 2.8
Consumed C102,% 0.39 0.49. 0.58
Viscosity, mPa•s -- 13.4
Brightness,%ISO 87.7 87.9 88.6
Filtrate Colour,CU -- 27 ---
Filtrate Metals,mg/L Ca=23.22 Fe=0.38 Mg=3A4 Mn=0.51
Tappi Dirt Aredppm(>.o.04mma)
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Allen Turner Pruyn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpharetta,GA. December 6,2001
Table I-7. Laboratory O-Do-Eop-D Bleaching of Lab Softwood LS Pulp
Sample ID Lab LS Brownstock AL7762001-002447
Kappa number 22.3
Viscosity,mPa•s 30.2
Brightness,%ISO 29.3
Bleaching Sequence: O-Do-Eop-D
O-Stage:60 min.,90°C,80 psi 10% consistency
Sample ID 2001-00 2560
NaOH,.% 1.6
Final pH 11.4
Kappa number 12.3
Viscosity,mPa•s 27.4
Brightness,%ISO 35.7
Filtrate Colour,C.U. 5640
Filtrate Metals,mg/L Ca=20.96 Fe=0.13 Mg=1.60 Mn=0.25
Dn-Stage:50 min.,60"C,mill filtrate added back to 10 % consistencv
Kappa Factor 0.22
C102 charge, % 1.03
Mill Filtrate Colour,C.U. 890
Final pH 2.1
Consumed C102, % 1.03
Brightness,%ISO 51.7
Filtrate Colour,C.U. 1090
Filtrate Metals,mg/L Ca=111.62 Fe=1.14 Mg=23.54 Mn=6.58
Eon-Stage:75 min..77°C,40 psi,10% consistency
Sample ID 2001-00 2855
NaOH charge, % 1.3
H2O2,charge,%4 0.5
Final pH 11.5
Consumed H2O7., % 0.5
Kappa number 2.1
Viscosity,mPa•s 17.5
Brightness,%ISO 70.9
Filtrate Colour,C.U. 1330
Filtrate Metals,mg/L Ca=71.14 Fe=3.27 Mg=24.96 Mn=6.75
D=Stage:240 min.,74"C.10 % consistency
Sample ID 2001-00 2856
CIOZ charge,% 0.4 0.6 0.8
NaOH,% 0.07 0.55 0.60
H2SO4,% --- ---
Final pH 3.3 5.6 7.6
Consumed CIOZ,% 0.4 0.45 0.48
Viscosity,mPa•s --- 17.1 --
Brightness,%ISO 87.1 88.5 86.4
Filtrate Colour,C.U. --- 34 ---
Filtrate Metals,mg/L Ca=8.78 Fe=0.27 Mg=1.72 Mn=0.30
Tappi Dirt Alea/ppin(>.0.04mmd) 34.08
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1 -L Allen Turner Pruyn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Table 1-8. Lab Two Stage Oxygen Delignifications of Mill Softwood Brownstock Pulp
Sample ID MM Brownstock 2001-002000
Kappa number 21.5
Viscosity, mpa•s 22.0
Brightness,%ISO 29.3
Oxygen Trial O 00 O-O
Sample ID 2001-00 2530 2760 2763
Stage l
NaOH,% 1.6 2.2 1.0
Time,min 60 30 30
Temperature,°C 90 100 100
Pressure,psi so 80 80
Consistency,% 10 10 10
Final pH --- --- 11.0
Stage 2
NaOH, % 1.0
Time,min - 60 60
Temperature,°C 90 90
Pressure,psi 80 80
Consistency, % -- 10 10
Final pH 11.5 11.7 11.5
Kappa number 12.6 9.8 11.3
Viscosity,mPa-s 16.3 14A 16.2
Brightness,%ISO 34.1 3&4 36.6
Filtrate Colour,C.U. 5330 6950 2715
Filtrate Metals, Ca=15.90 Fe=0.17 Mg=1.60 Ca=15.44 Fe=0.17 Mg--2.16 Ca=13.90 Fe=0.15 Mg=1.12
Mn=0.70 Mn--0.94 Mn=0.47
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Allen Turner Pruyn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Table 1-10 Tear and Tensile Index @ 400 CSF of Selected Softwood Pulps
Tensile Tear
Descriptive Index Index
LIMS ID ID (N.nVg)at (mN-m2/g) at
400 CSF 400 CSF
2001-002000 Mill Brownstock 86.3 9.5
2001-002003 Mill Oxygen 84.6 8.2
2001-002004 Mill Fully Bleached 88.1 8.5
5
2001-002853 Mill BS Lab O-Do-Eop-D 86.0 8.8
2001-002447 Lab LS Brownstock 08.9 11.3
2001-002560 Lab LS Oxygen 95.0 11.1
2001-002856 Lab LS O-Do-Eop-D 90.2 0..6. —
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Allen Turner Prayn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Figure 1-1. Total Yield versus Kappa Number for Lab Softwood Cooking
50
49
0 48
47
0046
� o
rYi c 45
0 0
e 44
0 43
m
42 +CK,EA=192%on wood
41 ■CK,EA=21.6%on wood
40 ♦LoSolids
16 18 20 22 24 26 28 30 32 34 36 38
Kappa Number
Figure 1-2. Laboratory Cooking Response for Softwood Furnish
38
36 "
+CK, EA=19.2% on wood
34 ■CK, EA=21.6% on wood
32 ♦LoSolids
L
30
E 28
Z
a 26
a
Y 24
22
20
18
16
800 1000 1200 1400 1600 1800 2000 2200 2400 2600 2800 3000 3200
H-factor
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Allen Turner Pruyn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Figure 1-3. Viscosity versus Kappa Number for Lab Softwood Cooking
50
45
40
N
ao35
E °o
c30
N O
O -- 25
O u
y
20ZL:
—
15 IOCK,FA=1s.2%anWood
,EA=21.6%on wood
10 S ids
16 18 20 22 24 26 28 30 32 34 36 38
Kappa Number
Figure 1-4. EA Consumed versus Kappa Number for Lab Softwood Cooking
22
= 21 ♦CK,FA=19.2°/n on wood
0
z 20 ■CK.EA=21.6%on wood
0 19 ♦Lo•sottds
0
18
0
e 17
m 16
E
of 15
c
rQOj 14
W 13
12
16 18 20 22 24 26 28 30 32 34 36 38
Kappa Number
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Allen Turner Pcuyn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Figure 1-5. Tear Index versus Tensile Index for Selected Mill and Lab Softwood Pulps
30.0
Mill BS
25.0
—.—Mill Oxygen
\ --MID Bleached
+ as L
g MAI BS Lab O-D-Eop-D
E 20.0 • —a—Lab LS BS
Lab LS Oxygen
Lab LS O-D-Eop-D
15.0
10.0
5.0
20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0 110.0
Tensile Index(N•mlg)
Figure 1-6. Tensile Index vers'ls PFI Revolutions for Selected Mill and Lab Softwood Pulps
110.0
100D
� W.0
E Mill BS
% 70.0
a Mill Oxygen
C
m 60.0 •—Mill Fully Bleached
F wD +Mill_BS Lab O-D-Eop-D
— —Lab LS BS
40.0
--Lab LS Oxygen
Lab LS O-D-Eop-D
20.0
0 1000 2000 3000 4DW MOD MOD 70M WW am
PFI Revolutions
CADa ma and Smingst hd0lnml Sm1aSs%TcTV=g lntcma Fdm\DLKA2001-00 Pan I SW Find Rtpomdm 17
a36n I
Allen Turner I'myn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part I
Alpheretta,GA December 6,2001
Figure 1-7.Mill Softwood Brownstock Pulp 2001-002000
30 150
I I i30
25 12110
%
vI 100 v
20
90 is
m I 80 c c
15
Y I .70
61) '
7 �
to 10
i I i 40 LL
i 30 a.
5 20
i 10
0 0
100 200 300 400 500 600 700 800 900 . 1000
Canadian Standard Freeness
+-Bulk —a Tear Index —A Burst Index - 9 PFI - o Tensile Index
(10, ar-?/9) (MN'rr'?/g) (10' kP&rrf/g) (10- revs) '(N•rrJg)
Figure 1-8. Mill Softwood Oxygen Pulp 2001-002003
150
I 140
130
2 120
5
110 X.
v 20 I I 10 c
I 90 x m
..T i 80 e c
�- 15 i 70 H
ri
m' # so m' m
10 50 m
40 d
30
5 20
i 10
0 0
100 200 300 400 500 600 700 800 900 1000
Canadian Standard Freeness(mL)
+(Bulk •-m--(Tear Index —i. Burst Index
1
—e—pFl13/9) —o—Tensile/In)de . (10' kPa rrtz/g)
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AL
Allen Turner Prayn's Island Technical Center
Andritz Ahlstrom Sales Lab Report 2001-068 Part i
Alpheretta,GA December 6,2001
Figure 1-9. Mill Softwood Fully Bleached Pulp 2001-002004
30 150
140
25 130.
120
X ! I I 110 m
'20 I 100
90ro- m
N ' ! ' e c
15 I 70
I I 60
m 10 I I 50 m K_
40 rL
a
5 }
I 20
10
0 0
100 200 3W 400 500 600 700 800 9W 1000
Canadian Standard Freeness(mL)
-s Bulk Tear Index -i—Burst Index --' ---- -
10' cm'/g) mN•m'/g) (10' kPa•m'/g)
r:jFigure 1-10. Mill Softwood BS Lab O-Do-Eop-D Bleached Pulp 2001-002853
3p 150
I ` 140
1 i 130
25 120
x i ' 110 m
10
20 I 100
90 m
15 m
Y
70
In 60 IC i
10 50 W
40 a
30
5 20
10
0 1 0
100 20D 300 400 5W 600 700 800 9W 1000
Canadian Standard Freeness(my
i Bulk —a—Tear Index Burs( Index
10' cm'!g) mN rrtZ/ ) (10' kPa m2/g)
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Allen Turner Pruyn's Island Technical Center
Andritz Ahistrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Figure 1-11. Lab Softwood Lo-Solids°Brownstock Pulp 2001-002447
30 150
I 140
25
130
I 120
v110 v
20 100 c
' 90 m m
15
80 e c
I I I 70 « F
m I 50 m m
10 I 50 �
I 40 a
I
I 30
5 20
i 10
0 0
100 200 300 400 500 500 700 800 900 1000
Canadian Standard Freeness(my
+Bulk — —Tear Index —+—Burst Index
10' aTivg) TN•rr>=! ) (16" kPa•rr?/g)
PM qnrtev
Figure 1-12. Lab Softwood Lo-Solids Oxygen Pulp 2001-002560
150
140
I i I I 130
I i 120
x i I 110 m
c 20 100
`m I I I m
15 I 80
Y 70 t-
m' I 60 m
10 50 a®'
40 LL-
IL
5 �
I 20
10
0 1 1 F I I i 1 0
100 200 300 400 500 600 700 800 90D 1000
Canadian Standard Freeness ImQ
—o—Bulk --0—Tear Index Burst Index —a PFI -o--•Tensile Index
(10' aTf/g) (mN•rTf/g) (10' kPa-0/g) (10-2 revs) (N-nV9)
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° $ Irk
Allen Turner Pruyn's Island Technical Center
Andritz Ablstrom Sales Lab Report 2001-068 Part 1
Alpheretta,GA December 6,2001
Figure 1-13. Lab Softwood Lo-Solids® O-Do-Eop-D Pulp 2001-002856
30 150
i I i I 140
130
25
j ! f 120
110 x
v 20 100 m
C
i I C
90 )-rq
60
t" 15 m
m I 70 «t-
m 60 a
mm
10 50
40 a
i I 30
! i i 20
10
01 0
100 200 300 400 500 600 700 800 900 1000
Cenadlan
e Bulk —a—Tear Index —t-Burst Index
10' arp/g) (10, kP&rr?/9)
CND=a nu and SndngsVmnAaIILLm1SmingsWcagarmy1mv F0co%OLKe1200"8PanISWFinalRcpm.dm 21
PRUYN'S ISLAND TECHNICAL CENTER
REPORT 2010-081
LABORATORY COOKING AND BLEACHNG
FOR
EVERGREEN PACKAGING
CANTON,NC
TO:
WILLIAM MILLER
Issued:
January 31, 2011
Issued by: Pamela O'Leary
Tel.(518)745-2992
Fax(518)745-2971
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report2010-081
Canton,NC January 31,2011
Summary
As part of a bleaching study, Evergreen Packing supplied PITC with softwood chips, mill
brownstock and fully bleached pulp. The mill wanted to compare the effect of two stage oxygen
delignification on bleach plant filtrate color development and final strength properties. The
kappa number on the mill brownstock tested too-low (23.2) to be used for our trials. Laboratory
conventional kraft cooking produced pulps with 26.0 and 30.5 kappa numbers.
Brownstocks were bleached using O-Do-Eo-D and 00-Do-Bo-D for comparison to a targeted
86% ISO brightness. Several 00 stages were performed targeting 60% delignification. All of the
bleaching process conditions were supplied by the customer. Testing included kappa number,
viscosity, chemical consumption and filtrate color after each bleach stage.
Observations
• Mill fully bleached pulps had a viscosity of 11.3 - 11.5 mPa-s and brightness of 85.5% -
85.6% ISO.
• Mill brownstock had a kappa number of 23.2 and viscosity of 19.3 mpa•s.
• Laboratory CK cooks produced kappa numbers 26.0 and 30.5.
• Delignification for single stage oxygen run on the 26.0 kappa number pulp achieved 48.5%
and a two stage achieved 61.4%.
• Two- stage oxygen ran on the 30.5 kappa number pulp achieved 59.3% delignification.
• The single 0 stage sequence consumed 20.6 kg/ADT of C102 in achieving 86.2% ISO
brightness.
• The two=stage 0 stage sequence consumed 16.0 kg/ADT of C102 in achieving 86.9% ISO
brightness.
• The 30.5 kappa number pulp consumed 17.8 kg/ADT of C102 in achieving 86.9% ISO
brightness.
• The color units ranged from 1490-55 for the single 0 stage sequence.
• The color units ranged from 940-41 for the two-stage oxygen performed on 26.0 kappa
brownstock.
• The color units ranged from 1300-45 for the two-stage oxygen performed on 30.5 kappa
brownstock.
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report 2010-081
Canton,NC January 31,2011
Standard Operating Procedures
Descripfion
PITC-P2 Conventional Kraft Cook -
PITC-P6 Deten-nining size and thickness distributions of wood chips
PITC-P7 Wood Chip Moisture Free Fraction
PITC-P9 Determining the moisture free fraction of pulp
PITC-P10 Determination of pulp yield
PITC-P 12 Screening a Iar a amount of pulp
TAPPI T230 Viscosity of pulp (capillaryviscosity method
TAPPI T236 Kappa#of pulp
TAPPIT248 Laboratory beating of pulp (PFI mill method
TAPPI T525 om-92 ISO brightness ad formation and testing)
PITC-B3 Oxygen Defignification
PITC-138 Chlorine Dioxide Bleaching
PITC-B6 Oxidative Alkaline Extraction
PITC-B 19 Pulp washing
NCASI TB#253 Color Determination
TappiT227 CSF
TappiT220 Bulk
Tappi T403 Burst
Ta _i T484 Tensile
Tappi T414 Tear
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report2010-081
Canton,NC January 31,2011
Photograph N. Mill supplied furnish from the digester feed belt.
04
�L E.ueN�fPf NYC -
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report 2010-081
Canton,NC January 31,2011
Photograph#2. Representation of PITC chip classification.
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report 0:
Canton,
Photograph . 11 1 1 from mill furnished digester feed belt before
PITC laboratory oo
c • t J
y \
L[ � � •� tom! �
x� 1 ,
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report2010-081
Canton,NC January 31,2011
Table#1. Results of PITC chip classification.
Job 2010-081
Lab+ID 120951
Descriptive ID Mill furnish digester belt feed chips
Chip Size 0.0-3.0 mm(%) 0.1 Chip Thickness 0-2 mm(%) 2.4
Chip Size 3.0-7.0 mm(%) 2.9 Chip Thickness 2-4 mm(%) 29.2
Chip Size 7.0-123ram(°/o) 16.4 Chip Thickness 4-6 nun(%) 37.5
Chip Size 12.7-25.4 min(%) 59.1 Chip Thickness 6-8 nun(%) 16.7
Chip Size 25.4-45.0 mm(%) 19.2 Chip Thickness 8-10 mm(°/o) 7.4
Chip Size>45.0 mm(%) 2.4 Chip Thickness>10 mm(%o) 6.8
Table 2 . Summary of pulping conditions and pulping results.
Furnish: 120951 Mixed southern softwood
Cook ID BC1661 AC3465 AC3466 AC3474
Cook Type CK CK CK CK
Screened Pulp Lab Plus ID 120973 121047 121117 121671
EA Charge
Total (% on wood) 20.6 20.6 20.6 20.6
Impregnation (% on wood NaOH) 20.6 20.6 20.6 20.6
WL Sulfidity (% AA) 29.3 29.3 29.3 29.3
Cooking Temperature (°C) 172.5 169.5 169.5 167.0
EA Consumed (% on wood NaOH)
Total 17.4 16.9 16.8 18.3
Impregnation Stage 9.3 9.5 9.3 9.7
Co-current 1 Stage 8.1 7.4 7.5 6.7
Residual EA(g/L NaOH)
End of Impregnation 32.3 31.8 32.4 31.0
End of Co-current 1 9.3 10.7 10.9 12.0
H-factor 1780 1330 1320 1110
Kappa Number 20.3 26.0 25.9 30.5
Viscosity(mPa•s) 20.6 27.8 27.2 32.5
Viscosity/Kappa Number Ratio 1.0 1.1 1.1 1.1
Brownstock Brightness (% ISO) 29.8 29.0 30.7 29.0
Brownstock Total Yield(% on wood) 43.5 44.5 43.7 44.6
Rejects (% on wood) 0.2 0.5 0.3 0.4
Screened Yield (% on wood) 43.3 44.0 43.4 44.2
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report2010-081
Canton,NC January 31,2011
Table 3 . O-Do-Eo-D Bleaching. Mill Fully Bleached Pulps
Lab Cook ID AC3465 Date Received 9/23110 1/13/11
Sample ID 12- 1047 120939 122146
Kappa Number 26.0 -- --
Viscosity, mPa•s 27.8 11.5 11.3
ISO Brightness, % 29.0 85.5 85.6
O Stage: 92°C, 60 min., 100 psi., 10% cons.
Sample ID 12- 1105
NaOH, % 2.0
Final pH 11.0
Kappa number 13.4
Delignification, % 48.5
Viscosity, mPa•s 20.8
ISO Brightness, % 37.2
Do Stage: 66°C.20 min., 10%cons.
Sample ID 12- 1111
Kappa Factor 0.24
CI02, as Cl2,% 3.2
Final pH 2.5
Residual g/L as Cl2 0
ISO Brightness, % 54.3
Filtrate color;C.U. 745
Eo Stage: 80°C, 60 min.. 35psi-O psi 10 min.,10% cons.
Sample ID 12- 1122
NaOH, % 1.2
Final pH 11.2
Kappa Number 3.2
Viscosity, mPa•s 19.3
ISO Brightness, % 60.9
Filtrate color, C.U. 1490
D Stage: 74°C. 240 min., 10% cons.
Sample ID 12- - 1148
CI02, as Cl2,% 2.1 2.6 3.2
NaOH,% 0.30 0.45 0.54
Final pH 3.6 3.9 3.8
Residual CIOZ g/L 0 0.0005 0.0015
Residual g/L, as Cl2 0 0.0013 0.0039
Viscosity, mpa•s -- 17.4 --
ISO Brightness, % 85.7 86.2 87.0
Filtrate color, C.U. 66 55 33
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report 2010-081
Canton,NC January 31,2011
Table 4 . 00-Do-Eo-D Bleachng.
Lab Cook ID AC3465 AC3466 AC3466 AC3474
Sample ID 12 1047 1156 1156 1671
Kappa Number 26.0 25.9 25.9 30.5
Viscosity, mPa•s 27.8 27.2 27.2 32.5
ISO Brightness, % 29.0 30.7 30.7 29.5
00 Stage: 140 psi+ 100 psi., 10% cons
Sample ID 12- 1106 1170 1171 1755
Time, min 20 + 60 20+60 20+60 20 + 60
Temperature, °C 85 + 92 89 + 93 93+99 89 + 99
NaOH, % 2.2 2.3 2.8 3.0
Final pH 11.0 10.8 11.0 11.0
Kappa number 12.3 12.2 10.0 12.4
Delignification, % 52.7 52.9 61.4 59.3
Viscosity, mPa•s 19.7 19.5 17.6 19.8
ISO Brightness, % 38.3 39.4 42.4 42.2
Do Stage: 66'C, 20 min.. 10% cons.
Sample ID 12- 1113 1759
Kappa Factor 0.24 0.24
CIOZ, as CIZ,% 2.4 3.0
Final pH 2.6 2.4
Residual g/L as CIZ 0 0
ISO Brightness, % 63.3 60.1
Filtrate color, C.U. 450 495
Eo Stage: 80°C. 60 min., 35psi-O psi 10 min.,10%cons.
Sample ID 12- 1185 1760
NaOH, % 1.1 1.0
Final pH 11.2 11.1
Kappa Number 2:8 3.1
Viscosity, mPa•s 16.7 19.4
ISO Brightness, % 67.0 64.6
Filtrate color, C.U. 940 1300
D Stage: 74°C. 240 min., 10%cons.
Sample ID 12- 1200 1761
CIOZ, as Cl2,% 1.6 2.1 2.6 1.6 2.1 2.6
NaOH,% 0.20 0.36 0.45 0.25 0.36 0.45
Final pH 3.4 3.9 3.8 4.2 4.1 4.2
Residual CIOZ, g/L 0 0.0004 0.0011 0 0.0007 0.0015
Residual g/L, as C12 0 0.0011 0.0029 0 0.0019 0.0038
Viscosity, mPa•s -- 14.5 -- -- 17.7 --
ISO Brightness, % 85.5 86.9 86.9 85.4 86.4 87.3
Filtrate color, C.U. 69 41 56 - 45 --
William Miller Pruyn%Island Technical Center
Evergreen Packaging Lab Report 2010-081
Canton,NC January 31,2011
Table 4.Physical Strength Properties
Cond Wt
Burst Tensile Tear Tensile Tensile
A E. .
Descriptive PFI CSF Bulk Index Index Index T. Stiffness Elongation Stiffness Thicknes
LIMS ID ID (#revs) (mL) (9m) (cm'/g) (kPa•m'/g) (N•m/g) (mN-elg) /m2) (kN/m) (mm) Index s(mm)
(kNm/g)
120938 0.0 649 6.55 1.72 2.75 41.55 17.65 64.66 392.2 3.17 5.99 0.563499
500 637 6.54 1.56 4.04 62.58 12.54 93.52 496.5 3.22 7.59s 0.509549
Mill Fully 2500 517 6.44 1.44 5.11 79.33 9.76 115.51 556.1 3.29 8.63 0.462635
Bleached 5000 357 6.51 1.37 5.75 85.27 8.29 143.59 567.4 3.79 8.72 0.446836
Rec'd 9/22/10 7500 239 6.63 1.34 5.85 85.11 8.32 . 125.03 611.6 3.20 9.23 0.444474
121148 0.0 704 6.54 1.73 2.42 38.14 30.12' 60.34 362.1 3.18 5.54 0.567080
500 683 6.56 1.52 4.73 67.14 17.99 111.82 485.3 3.66 7.40 0.497941
O-Do-Eo-D 2500 573 6.77 1.41 6.25 89.65 13.03 146.83 591.6 3.62 8.74 0.476199
26.0 BS 5000 439 6.46 1.36 6.67 95.15 11.89 157.23 578.2 3.85 8.95 0.438988
Kappa# 7500 321 6.49 1.34 7.10 94.93 11.49 147.74 588.5 3.60 9.07 0.433222
121200 0.0 700 6.54 1.70 2.37 35.87 27.95 56.24 340.5 3.14 5.21 0.555599
500 678 6.57 1.51 4.64 62.40 16.91 101.64 464.5 3.57 7.07 0.497230
00-Do-Eo-D 2500 579 6.50 1.38 6.09 81.37 12.49 131.54 539.9 3.64 8.31 0.446963
25.9 BS 5000 431 6.41 1.37 6.86 92.71 11.61 140.39 574.7 3.52 8.97 0.438432
Kappa# 7500 300 6.42 1.33 7.13 94.96 10.92 157.99 562.1 3.90 8.76 0.425907
121761 0.0 696 6.42 1.71 2.51 38.18 28.68 42.89 379.0 2.33 5.90 0.547420
500 665 6.64 1.50 4.85 67.74 16.77 103.26 496.6 3.31 7.48 0.497535
00-Do-Eo-D 2500 553 6.41 1.41 6.33 90.34 12.99 135.13 586.1 3.46 9.14 0.450672
30.5 BS 5000 409 6.46 1.35 6.80 93.64 11.49 157.07 596.5 3.88 9.23 0.434594
Kappa# 7500 279 6.58 1.32 7.08 97.49 10.78 170.33 597.2 3.98 9.08 0.433324
122146 0.0 692 '6.31 1.77 2.82 39.46 19.45 67.64 351.2 3.59 5.57 0.559511
Mill Fully 500 650 6.45 1.53 4.28 63.11 12.75 90.82 490.6 3.16 7.61 0.492048
Bleached 2500 504 6.53 1.39 5.36 81.50 9.68 124.00 554.0 3.42 8.48 0.454329
Received 5000 340 6.47 1.31 5.78 86.76 8.39 131.03 580.8 3.45 8.98 0.424586
1/13/11 7500 212 6.40 1.29 5.98 90.99 8.06 132.93 594.0 3.37 9.28 0.413639
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report 2010-081
Canton,NC January 31,2011
Table 5 Tear and Tensile IndetA 400CSF of Selected Softwood Pulps
Tensile Tear
Index Index
Descriptive (N•m/g)at (mrhm'/g)at
LIMS ID ID 400 CSF 400 CSF
120938 Mill Fully Bleached 9 (reed 9/23/10) 83.7 8.7
121148 O-Do-Eo-D 26.0 kappa#Lab CK 95.1 11.8
121200 00-Do-Eo-D 25.9.0 kappa#Lab CK 93.2 11.5
121761 00-Do-Eo-D 30.5 kappa #Lab CK 93.9 11.4
122146 Mill Fully Bleached(reed 1/13/11) 84.8 8.9
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report 2010-081
Canton,NC January 31,2011
Figure 1. Tensile versus Canadian Standard Freeness of laboratory cooks.
Tensile vs CSF Index
140.00
120.00 - - -
100.00 - - — -.
'm
E
i 80.00
K
N
9
C
a
60.00
i; +fO-Oo-Eo-Od°ach
r
40.00 tmAl N hbed�K2
20.00
0.00
0 100 200 300 400 500 e00 700 e00
CSF(MI)
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report 2010-081
Canton,NC January 31,2011
Figure 2. Tensile Index versus PFI.
Tensile Index vs PFI Revs
140.00
120.00
100.00
rn
80.00 —
N
0
9
C
m
•w 60.00 - -
C
m
F
40.00
tmill fully bleach
tO-Do-Eo-O
-+ O&Do-Eo-D
20.00 9-00-Do-E,D
-f-mill fully bleach#2
0.00
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0
PFI(#of revs)
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report 2010-081
Canton,NC January 31,2011
Figure 3. Tear Index versus Tensile Index on PITC laboratory cooks.
Tear Index vs Tensile Index
35.00
30A0 —
25.00
E 20.00 —
E
E
x
m
a
15.00 —
A
A
f
10.00
+mill sully bleach
t0-Do-Eo-D
�00-Do-Eo-D
+00-DaEo-D
5.00 i Mlll WHY bleach#2
0.00
0.00 20.00 40.00 60.00 60.00 100.00 120.00 140.00
Tensile Index(N-nVg)
William Miller Pruyn's Island Technical Center
Evergreen Packaging Lab Report2010-081
Canton,NC January 31,2011
Miscellaneous Information
All samples included in this report will be held in cold storage for three months after issuance of
the report. At that time, the samples will be discarded without notice. If there is a need to retain
samples longer than the three-month grace period, please contact PITC.
Laboratory Study of Likely Effects of
Installing Two-Stage Oxygen
Delignification at Evergreen
Packaging's Canton, NC Mill
Final Report
Thomas J. McDonough
June 29, 2011
Confidential
Executive Summary
This report describes a study undertaken to-study and document the effects of replacing the Canton mill's
single-stage oxygen delignification system with a two-stage system. The effect on effluent color was of
particular interest.Pulps were prepared in the laboratory from Canton mill chips under conditions chosen to
simulate(1) mill pulping to the normal kappa number level of 26 and(2) a scenario under which cooking
would be terminated at a kappa number of 30.5 .The 26 kappa pulp was then subjected to single-stage and
two-stage oxygen delignification, using mill conditions for the single-stage process and conditions for the
two-stage process that were chosen to increase the degree of delignification to approximately 60%. The
high-kappa pulp was also subjected to the same degree of two-stage oxygen delignification. All three
oxygen pulps were subjected to D(EO)D bleaching to brightness levels in the 86—87 range.
Relative to the single-stage(0)pulp, the two-stage(00) pulp of initial kappa 26 consumed 23%less C102
and had a viscosity of 14.5 units vs. 17.4 units for the 0 pulp. By employing the two-stage oxygen process
the color of the first D stage filtrate was reduced from 745 units to 450, and the color of the(EO) stage
filtrate from 1490 units to 940. However, at a fixed value of tensile strength (70 N.m/g), the tearing
resistance of the 00 pulp (14.8 mMrrZ/g) was about 15% lower than that of the O pulp (17.0 mN.M2/g).
The high-kappa pulp after two oxygen stages consumed 16% less C102 than the single-oxygen-stage pulp
and had a fully bleached viscosity(179)which was virtually the same as that of the single-oxygen-stage
pulp. In this case, the color of the first D stage filtrate was reduced from 745 units to 495, and the color of
the(EO) stage filtrate from 1490 units to 1300.The tearing resistance of the fully bleached pulp (16.4
/ mN.mZ/g) was only slightly lower than that of the reference(0) pulp.
The tear strength deficiency of the 26 kappa pulp after two-oxygen-stages was not due to a fiber strength
loss but rather to the fact that the 00 pulp had to be beaten to a higher sheet density in order to achieve a
given tensile strength.
Compared to the samples prepared in the laboratory, recent mill bleached samples had lower strength
properties. This may reflect lower uniformity of treatment under mill conditions as well as detrimental
effects of process equipment such as blow valves, pulps, etc., which laboratory pulps are not subjected to.
Introduction
The Canton mill employs the OD(EO)D bleaching sequence to produce bleached softwood pulp. The mill
commissioned a laboratory study to predict the effects of replacing the current single-stage oxygen
delignification system with a two-stage system, a change that can be expected to reduce the color level's of
the mill's effluent.
Mill chips were laboratory pulped to two different kappa numbers, one typical of that achieved in the mill
(26), and one 4.5 units higher. One kappa 26 pulp sample was bleached under conditions chosen to
simulate the OD(EO)D sequence currently used in the mill,as a control. A second, similar sample was
bleached under conditions chosen to simulate replacement of the single oxygen stage with a two-stage
system, leaving the unbleached(brownstock) kappa number unchanged. Finally, the 30.5 kappa number
pulp was subjected to two-stage oxygen delignification followed by bleaching to high brightness.
After each stage, the pulps were characterized by suitable measurements (kappa number, brightness and/or
viscosity, depending on the stage) and the color of the effluent from each of the last three stages was
measured. In addition, fully bleached samples were subjected to laboratory refining and the physical
properties of the refined pulps were measured.
- 1 -
Results and Discussion
Oxygen Delignification and Multistage Bleaching
Table 1 shows the results obtained by oxygen delignification of the laboratory pulps.The unbleached 26
kappa pulp viscosities,27.2 and 27.8,were higher than those typically observed in the mill. As expected,
the 30.5 kappa unbleached pulp had a viscosity (32.5) that was substantially higher than that of the 26
kappa pulp. Single-stage oxygen with 2.0%NaOH at 92°C achieved 48.5% delignification, which
compares well with the recent average of 48.7% in the mill. To increase the degree of delignification of the
26 kappa pulp to 61.4% with two-stage oxygen it was necessary to apply 2.8%NaOH, with temperatures of
93 and 99°C in the first and second stages, respectively. Relative to the results in the single-stage case this
increased the brightness from 37.2 to 42.4 and decreased the viscosity from 20.8 to 17.6 mPa.s. In the case
of the 30.5 kappa unbleached pulp 59% delignification was achieved by increasing the caustic charge to
3.0%.This resulted in a brightness of 42.2 and viscosity of 19.8 mPa.s,
Table 1.Laboratory Oxygen Delignification Results
Single-
Stage Two-Stage Oxygen
Oxygen
Unbleached Pulp
Kappa Number 26.0 26.0 25.9 25.9 30.5
Viscosity, mPa•s 27.8 27.8 27.2 27.2 32.5
ISO Brightness, % 29.0 29.0 30.7 30.7 29.5
Oxygen Delignification
140+ 140+ 140+ 140+
Oxygen pressure, psig 100 100 100 100 100
Time, min 1 60 20+60 20+60 20+60 20+60
Temperature, °C 92 85 +92 89 +93 93 +99 89 +99
NaOH, % 2.0 2.2 2.3 2.8 3.0
Final pH 11.0 11.0 10.8 11.0 11.0
Kappa number 13.4 12.3 12.2 10.0 12.4
Delignification, % 48.5 52.7 52.9 61.4 59.3
Viscosity, mPa•s 20.8 19.7 19.5 17.6 19.8
ISO brightness, % 37.2 38.3 39.4 42.4 1 42.2
Table 2 contains the results of full bleaching of the oxygen delignified pulps. The single-oxygen-stage pulp
was bleached to a brightness of 87.0 with a total C102 consumption of 2.43% (6.4% as C12). After two
oxygen stages, the 26 kappa pulp was bleached to a brightness of 86.9 with a total C102 consumption of
1.71%and the 30.5 kappa pulp reached a brightness of 86.4 with a total C102 consumption of 1.94%. After
full bleaching, the viscosity of the single-oxygen-stage pulp was 17.4. After two-stage oxygen and full
bleaching, the 26 kappa brownstock yielded a viscosity of 14.5.The corresponding viscosity after full
bleaching of the 30.5 kappa brownstock was 17.7,which was nearly the same as the fully bleached
viscosity after applying a single oxygen stage to 26 kappa brownstock. At the normal brownstock kappa
number of 26, going from one oxygen stage to two decreased the D.filtrate color from 745 to 450 units (a
40%reduction) and the(EO) filtrate color from 1490 to 940 units (a 37%reduction). When the brownstock
kappa was increased from 26 to 30.5,the filtrate color reductions were smaller:,Going from one oxygen
stage to two decreased the D°filtrate color from 745 to 495 units (a 34% reduction) and the(EO)filtrate
color from 1490 to 1300 units(a 13%reduction). In all cases,the D, filtrate color, already low, was not
changed significantly.
- 2-
Table 2. Results of Bleaching Oxygen Delignified Pulps
No. of Oxygen Stages 1 2 2
Unbleached kappa number 26 26 30.5
Kappa number after oxygen 13.4 10.0 12.4
Viscosity, mPa•s 20.8 17.6 19.8
ISO Brightness, % 37.2 42.4 42.2
Do Stage: 66°C,20 nun.,'10% cons.
C102, as C12,% 3.2 2.4 3.0
Final pH 2.5 2.6 2.4
Residual g/L as C12 0 0 0
ISO Brightness, % 54.3 63.3 60.1
Filtrate color, C.U. 745 450 495
(EO)Stage: 80°C,60 min.,35psi-O
psi/10 min.,10% cons.
NaOH, % 1.2 1.1 1.0
Final pH 11.2 11.2 11.1
Kappa Number 3.2 2.8 3.1
Viscosity, mPa•s 19.3 16.7 19.4
ISO Brightness, % 60.9 67.0 64.6
Filtrate color, C.U. 1490 940 1300
D, Stage: 74°C,240 min., 10% cons.
C102, as C12,% 2.1 2.6 3.2 1.6 2.1 2.6 1.6 2.1 2.6
NaOH,%a 0.30 0.45 0.54 0.20 0.36 0.45 0.25 0.36 0.45
Final pH 3:6 3.9 3.8 3.4 3.9 3.8 4.2 4.1 4.2
Residual C102, g/L 0 0.0005 0.0015 0 0.0004 0.0011 0 0.0007 0.0015
Total Sequence C102.% 2.02 2.21 2.43 1.52 1.71 1.90 1.75 1.94 2.13
Residual g/L, as C12 0 0.0013 0.0039 0 0.0011 0.0029 0 0.0019 0.0038
Viscosity, mPa•s -- 17.4 -- -- 14.5 -- -- 17.7 --
ISO Brightness, % 85.7 86.2 87.0 85.5 86.9 86.9 85.4 86.4 87.3
Filtrate color, C.U. 66 55 33 69 41 56 1 45
3
Figure 1 shows the relationship between post-oxygen viscosity and kappa number.The decrease in kappa
number achieved by increasing the severity of oxygen delignification is inevitably accompanied by a loss
of viscosity(and, by implication, a corresponding loss in cellulose degree of polymerization). However,
by increasing the unbleached kappa number, the viscosity after two oxygen stages (represented by the
lower square data symbol) was restored to a value close to that obtained after a single oxygen stage.
35
30
Y!
L
EZ=6
ached
n Stock
a 25
N
O
O
In
>
20es
15
5 10 15 20 25 30 35
.Kappa Number
Figure 1. Viscosity vs. kappa number after oxygen delignification
Figure 2 illustrates the favorable effect of two-stage oxygen on total C102 consumption. At a final
brightness level of 87.0,and under the conditions of these experiments, a 23%reduction in total C102
consumption may be expected when the brownstock kappa number is 26.Raising the brownstock kappa
number to 30.5 causes a modest increase, but the decrease in C102 consumption is still significant.
Relative to the base case(kappa 26 brownstock, one oxygen stage), the decrease is 16%.
88
y=6.W..76.66
y=3.66X+60.13 Y=&M.nm
87 .. ... --- . - ..:_.. —___...______...._. .—
N
d -
t 86
OI
m
85 •♦10-Stage
2 0.Stages
♦HI-K+20.Sta es
84
1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6
Total C102(Da+D1)as C102,%
Figure 2.Final brightness vs.total C102 consumption
4
Physical Properties of Bleached Pulps
Table 3 contains the results of physical properties testing of pulp bleached in the mill, pulp bleached in
the lab with a single oxygen stage, and 26 kappa and 30.5 kappa pulps bleached in the lab with two
oxygen stages.
Table 3.Physical Properties of Bleached Ptd s
Tensile Burst Tear Tensile
Pulp PFI CSF Density Index Index Index T.E.A. Elongation Stiffness Index
ID (revs) (mL) (g/cna3) (N.m/g) (kPa-0/g) (�•�/g) Q/m2) (Earn)10') (kNnVg)
0.0 649 0.58 41.55 2.75 17.65 64.66 3.17 5.99
0.5 637 0.64 62.58 4.04 12.54 93.52 3.22 759
Mill Bleached 2.5 517 0.69 79.33 5.11 9.76 115.51 3.29= 8.63
5.0 357 0.73 85.27 5.75 8.29 143.59 3.79 8.72
7.5 239 0.75 85.11 5.85 8.32 125.03 3.20 9.23
0.0 704 .0.58 38.14 2.42 30.12 60.34 3.18 5.54
0.5 683 0.66 67.14 4.73 17.99 111.82 3.66 7.40
O-Do-Eo-D 2.5 573 0.71 89.65 6.25 13.03 146.83 3.62 8.74
5.0 439 0.74 95.15 6.67 11.89 157.23 3.85 8.95
75 321 0.75 94.93 7.10 11.49 147.74 3.60 9.07
0.0 700 0.59 35.87 2.37 27.95 56.24 3.14 5.21
0.5 678 0.66 62.40 4.64 16.91 101.64 3.57 7.07
00-Do-Eo-D 2.5 579 0.72 _ 81.37 6.09 12.49 131.54 3.64 8.31
Kappa 26 5.0 431 0.73 92.71 6.86 11.61 140.39 3.52 8.97
7.5 300 0.75 94.96 7.13 10.92 157.99 3.90 8.76
0.0 696 0.58 38.18 251 28.68 42.89 2.33 5.90
00-Do-Eo-D 0.5 665 0.67 67.74 4.85 16.77 103.26 3.31 7.48
Kappa 30.5 2.5 553 0.71 90.34 6.33 12.99 135.13 3.46 9.14
5.0 409 0.74 93.64 6.80 11.49 157.07 3.88 9.23
7.5 279 0.76 97A9 7.08 10.78 170.33 3.98 9.08
Figure 3 shows the relationship between tearing resistance and tensile strength for each of the four pulp
types. It is apparent that,at a tensile index of 70 N.m/g the 26 kappa pulp after two oxygen stages had a
roughly 15%lower tear relative to the base case(single-oxygen stage applied to 26 kappa pulp). This tear
strength deficiency was reduced to about 5%by raising the unbleached kappa number from 26 to 30.5.
The"mill bleached"pulp had lower tear strength than the lab single-oxygen-stage pulp. This may be
explained by harsher physical treatment of mill pulp due to blow valves, pumps and other process
equipment.
At first glance, the tear strength deficiency of the 00 pulp suggests that it has lower fiber strength than
the 0 pulp; the tear strength of well-bonded beaten pulps is dominated by fiber strength since tear failure
in such pulps occurs primarily by fiber breakage, rather than by bond failure and fiber pullout. On closer
examination, however, a different conclusion can be reached, as explained below.
5
35
30 \ ,A •Mill Bleached
\,� ♦ODIEO�D
rn
E 25 \ ■OODIEOID
20 \
D \
C
F 15
10
5
20 30 40 50 60 70 80 90 100 110
Tensile Index,N.m/g
Figure 3. Tearing resistance vs. tensile index.
Fiber Strength vs. Bond Strength
Figure 4 is a plot of tensile strength versus sheet density. Such plots typically display a linear rise
followed by a leveling off to an almost horizontal plateau.As beating progresses, fiber conformability is
increased, resulting in increased bonded area and greater overall level of bonding, which is manifested in
higher sheet density and higher tensile strength. As beating progresses beyond a certain point, however,
bond strength becomes so great that fiber breakage becomes significant and the tensile strength of the
sheet is determined by fiber strength. Thus,the tensile strength at which the leveling off occurs can be
taken as a measure of fiber strength.
110
100
•Mill 8lexthed
90 •oIXE01D
■OOIXE
E 80 ♦Hi-K-0OD(EO)D ■
i
i
w 70 �
i
a �
c
y 60 �
ac 50
f �
i
i
40 i
i
i
30 i
20
0.50 0.55 0.60 0.65 0.70 0.75 0.80
Sheet Density,g/cm3
Figure 4. Tensile strength vs.sheet density
6
The current data are no exception to this rule. All of the lab oxygen delignified pulps, whether single
stage or two-stage level off at about the same value of tensile strength.To the extent that this limiting
tensile can be taken as a measure of fiber strength, it may be concluded that these pulps have equally
strong fibers. It is also significant that, in the earlier stages of beating, the 26 kappa 00 pulp has a lower
tensile strength at a given density.This suggests that this pulp has lower specific bond strength than the 0
pulp. The tensile strength of the mill pulp levels off at a lower value, suggesting that the less uniform and
harsher treatment suffered by the pulp in the mill has resulted in fiber strength losses.
Figure 5 shows how tear strength is affected by beating. As beating progresses and sheet density is
increased, the tear strength is decreased as a result of the adverse effect of increased bonding on the
degree to which tear failure occurs by fiber pullout, as opposed to fiber breakage. (Since fiber breakage
offers less resistance to tear failure than fiber pullout the tear strength decreases with beating.) A
conclusion that may be drawn from Figure 5 is that,at a given sheet density, all of the lab oxygen
delignified pulps have the same tear strength, regardless of the number of oxygen stages used.
35
•MIII Bleached
30
♦OD(EO)D
� ■OOD(EO)D
"E 25 ♦Hi-K-OOD(EO)D
z
E
x 20
m
a
c
m 15
10
5
0.55 0.60 0.65 0.70 0.75 0.80 0.85
Sheet Density,g/cm'
Figure 5. Effect of beating on tear strength.
The 26 kappa two-oxygen-stage pulp had lower tear strength at fixed tensile strength than the
corresponding single-oxygen-stage pulp, not because its fibers were weaker but rather because it had to be
beaten to a higher sheet density to achieve the same level of tensile strength(as shown in Figure 4), with
the result that its tear was lower(as shown in Figure 5). In contrast,the high-kappa two-oxygen-stage
pulp had a tensile-density relationship that was nearly the same as that of the 26 kappa two-oxygen-stage
pulp, with the result that both pulps had similar tear at fixed tensile.
Burst Strength and Tensile Stiffness
Figure 6 shows the relationship between tensile strength and burst strength for the four pulp types. At a
given tensile strength level, the burst strength tends to be lowest for the mill bleached pulp and highest for
the 26 kappa two-stage oxygen pulp. This may reflect differences in the shape of the stress-strain curves
for the different pulp types. As is apparent from Table 3, the mill bleached pulp is stiffer and has lower
7
elongation and tensile energy absorption than the oxygen bleached pulps. This causes it to fail earlier
when subjected to increasing bursting pressure. There is also evidence that the 26 kappa two-stage oxygen
pulp has higher burst at a given tensile than the single-stage oxygen pulp, a difference that correlates with
its lower stiffness, as shown in Figure 7. The burst-tensile characteristic of the high-kappa two-oxygen-
stage pulp was similar to that of the 26 kappa single-oxygen-stage pulp. This correlates with the fact that
the two had similar stiffness values, as shown in Figure 7.
8
7 •Mill Bleached
♦OD(EO)D /
T 6 ■OOD(EO)D
•HI-K-OOD(EO)D
a 5
Y
K v
N /
c 4 /
rq /
/
M 3 /
2
1
20 30 40 50 60 70 80 90 100 110
Tensile Index, N.m/g
Figure 6. Burst index vs. tensile index
10
•
E Oi
a%i 8
c .i•/
• / '` •Mill Bleached
G
m 6 /
■OOD(EO)D
F ♦Hi-K-OOD(EO)D
4
0.55 0.60 0.65 0.70 0.75 0.80 0.85
Sheet Density,g/cm'
Figure 7. Tensile stiffness index vs. sheet density
8
Response to Refining
As shown in Figure S, the unbeaten mill pulp sample exhibited lower freeness than the oxygen delignified
samples,which were similar to each other in regard to freeness. As beating progressed, this difference in
freeness persisted. The lower freeness of the mill pulp suggests that it had higher specific surface at any
given level of refining. A likely explanation is that the mill pulp had a higher content of fines, either
because of a different species composition(higher hardwood content) or because of the harsher treatment
inflicted by mill mechanical processes (mixing, pumping, etc.). The high-kappa pulp after two oxygen
stages beat at a slightly faster rate than the other two lab pulps.
In future experiments it would be desirable to measure and control the species composition and to
measure the fines content and fiber length distribution,for example by use of the Fiber Quality Analyzer.
600
700
600
>EL
500 400
`n300200
♦ HI-K-OOD(EO)D
100
0
0 1 2 3 4 5 6 7 6 9
PFI Revs x 104
Figure S. Freeness vs. number of revolutions in the PFI mill
Figure 9 compares the rate of densification of the three pulps during beating. At intermediate levels of
refining the oxygen pulps densified at similar rates and more rapidly than the mill pulp.
Assessment of the "Mill Bleached" Pulp Sample
The properties of the sample of mill-bleached pulp were generally inferior to those of the single-oxygen-
stage lab pulp. At the same tensile strength level the tearing resistance of the mill bleached pulp was more
than 30% lower than that of the single-oxygen-stage lab pulp. It had a lower maximum tensile strength
and lower tear at the same density. Both observations suggested that it had weaker fibers than the lab
pulps. At a given level of refining the mill pulp had both lower freeness and lower sheet density than the
lab pulps.These discrepancies between the properties of the mill pulp and the lab pulp intended to
simulate it were of some concern. They are probably due, at least in part,to the relatively harsher and
less uniform treatment experienced by the pulp under mill conditions, as compared to the gentler and
more uniform treatment under lab conditions. They may also reflect differences between mill operating
conditions prevailing at the time of collection of the sample submitted to the lab from more normal mill
operating conditions. Measurement of the viscosity of the mill bleached sample submitted to the lab
yielded a value of 11.3 - 11.5 mPa.s, which is consistent with its lower tear strength.
9
To allow further investigation of the degree to which the present mill pulp sample was representative, the
mill provided data on pulp from presumably normal production runs. The data included physical
properties measurements on nine samples for which viscosity data were also available. Tear-tensile plots
for these nine samples are shown in Figure 10, which also includes the"Mill Bleached"pulp data from
Figure 3 and the results of evaluation of a second"Mill Bleached" sample that was collected after
completion of the initial lab study.
0.80
0.75
■
�U 0.70 ■
0
0.65
1
O •Mill Bleached
♦OD(EO)D
t 0.60 ■OOD(EO)D
N ♦Hi-K-OOD(EO)D
0.55
0.50
0 1 2 3 4 5 6 7 8 9 10
PFI Revs x 10-3
Figure 9. Sheet densification during refining
35
•Mill Bleached •Visa 135
30 •Visc.14.6 •Visc.11.6
•Visc.12.1 •Visc.10.3
.Visc.17.7 •Visc.12.3
p, 25 s Visc.14.61 •Visc.13.6
E ♦Mill Bleached 2
E 20
x
d
15
`m
v
10
5
0
20 30 40 50 60 70 80 90 100 110 120 130 140
Tensile Index,N.m/g
Figure 10.Tear vs. tensile for pulps produced in the mill
10
It is apparent from Figure 10 that the"Mill Bleached"sample evaluated as part of the current lab study
had lower tear strength than all of the previously evaluated samples, confirming that it was not typical of
the mill production samples previously evaluated.This conclusion was reinforced by the fact that a
second mill sample, "Mill Bleached 2" had strength characteristics that were very similar to those of the
first one. This suggests current mill process operations subject the pulp to harsher conditions than during
past operations, when the previous samples were taken.
Regression equations for each of the plots in Figure 10 were used to calculate the tear index at a tensile
index of 70 N.m/g. The resulting tear indices are plotted against pulp viscosity in Figure 11.
20
m
E
i 18
E O
k
a
a C 16 O Y•031Pa8]91
d
N
C
F 0
14 0
0 ) 0
x
m O
9 '
C 12
R
d
f
10
8 10 12 14 16 18 20
Viscosity,mPa.s
Figure 11.Tear index interpolated to 70 tensile index vs. viscosity(historical mill data).
Figure 11 suggests that the viscosity reduction that results from switching from a one-stage to a two-stage
oxygen delignification process is likely to have pulp strength implications.
Summary and Conclusions
Pulps were prepared in the laboratory from Canton mill chips under conditions chosen to simulate(1) mill
pulping to the normal kappa number level of 26 and(2) a scenario under which cooking would be
terminated at a higher kappa number(30.5).The 26 kappa pulp was then subjected to single-stage and
two-stage oxygen delignification, using mill conditions for the single-stage process and conditions for the
two-stage process that were chosen to increase the degree of delignification to approximately 60%. This
higher degree of delignification was achieved by applying 2.8% caustic(vs. 2.0% in the single-stage
system) and subjecting the pulp to a 20-minute, 140 psig, 93°C first stage followed by a 60-minute, 100
psig, 99°C second stage. The high-kappa pulp was also subjected to two-stage oxygen delignification. In
this case, 59%delignification was achieved by applying 3.0%caustic and first-and second-stage oxygen
temperatures of 89 and 99°C. All three oxygen pulps were subjected to D(EO)D bleaching to brightness
values in the 86—87 range and the physical properties of the bleached pulps were determined after
laboratory refining.
Relative to the single-stage(0)pulp, the two-stage(00)pulp of initial kappa 26 consumed 23%less
C1O2 and had a viscosity of 14.5 units vs. 17.4 units for the 0 pulp. By employing the two-stage oxygen
process the color of the first D stage filtrate was reduced from 745 units to 450,and the color of the(EO)
stage filtrate from 1490 units to 940. However, at a fixed value of tensile strength(70 N.m/g), the tearing
' 11
i
resistance of the 26 kappa 00 pulp (14.8 mN.m2/g) was about 15% lower than that of the 0 pulp (17.0
mN.m2/g).
The high-kappa two-oxygen-stage pulp consumed 16%less C1O2 and had a viscosity(17.7) which was
virtually the same as that of the single-oxygen-stage pulp. In this case, the color of the first D stage filtrate
was reduced from 745 units to 495, and the color of the (EO) stage filtrate from 1490 units to 1300.The
tearing resistance of the fully bleached pulp (16.4 mN.m2/g) was only slightly lower than that of the
reference(0)pulp.
The tear strength deficiency of the 26 kappa two-oxygen-stage(00) pulp was not due to a fiber strength
loss but rather to the fact that the 00 pulp had to be beaten to a higher sheet density in'order to achieve a
given tensile strength. The 00 pulp had lower specific bond strength(lower bond strength per unit of
bond area)than the 0 pulp. At a given tensile strength, the 00 pulp had higher burst strength than the 0
pulp. This correlates with the lower tensile stiffness of the 00 pulp. During refining, the 00 pulp
densified more rapidly than the 0 pulp, although its freeness fell at the same rate. This suggests that the
fibers of the 00 pulp have cell walls that are more readily destructured and/or hydrated.
Comparison with historical mill data showed that tear strengths of both of the"Mill Bleached" samples
evaluated as part of the current lab study were at the lower end of the range over nearly the whole range
of tensile indices, which implies that current mill process conditions are harsher and result in lower pulp
strength than when previous samples were taken for strength evaluation.
Analysis of mill data suggests that the viscosity reduction that would result from adding a second stage of
oxygen delignification is likely to have pulp strength implications. Utilization of two-stage oxygen
delignification mill pulp may be expected to lead to lower final viscosity than the current 11.3-11,5
mPa.s, and correspondingly lower physical strength properties.
Recommendations for Further Study
It may be desirable to perform a second comparative evaluation of one- and two-stage oxygen
delignification under conditions that closely mimic those of the mill process. More specifically,by
proceeding according to the following steps:
a) Obtain representative samples of the pulp entering the O-stage, with its accompanying liquor. Make a
composite of samples gathered over several shifts.
b) Measure the unwashed kappa number of this sample, and then wash a subsample thoroughly to get a
washed kappa number, to characterize the degree of washing that has been achieved in the mill.
c) Have the lab separate liquor from the sample, wash the pulp,then add liquor back in the amount
needed to raise the kappa number to that of the unwashed sample.
d) Do one- and two-stage oxygen delignification of samples having unwashed kappa number equivalent
to mill values,using samples prepared as in step (c) above.
e) Complete the bleaching sequence on both pulps, using the mill's kappa factor(presumably based on
the washed kappa number of the oxygen stage pulp) in the Do stage. Simulate bleach washer
inefficiency by carrying over 20%of the filtrate from each stage to the next.
f) Do measurements as in the previous experiments: brightness, residuals, viscosities, combined effluent
color,PFI runs and physical properties. Reverted brightness may also be of interest.
g) Do additional measurements to facilitate interpretation of the results: Fiber Quality Analyzer(FQA)
determination of fiber size distributions, coarseness and fines content on both unbeaten and refined
pulps.
This would address questions that could arise about the relevance of the previous results, in view of the
difference between the properties of the lab-bleached and mill-bleached pulps.
12