NCD980602163_19950804_Warren County PCB Landfill_SERB C_Innovative Technology for Cleanup at Landfill-OCR

~ , -:::--aQuaTerra® CORPORATE H EADQUARTERS : '7"'=" POST OFFICE Box 37579 • RALEIGH, NC • 27627-7579 • [phone] • FAX [phone]
A GREAT LAKES CHEMICAL CORPORATION COMPANY
August 4, 1995
Mr. Henry Lancaster
Legislative Liaison
North Carolina Department of Environment, Health, and Natural Resources
14th Floor
512 North Salisbury Street
Raleigh, North Carolina 27611
Reference: Aquaterra, Inc.
Innovative Technology for Cleanup at Warren County PCB Landfill
Dear Mr. Lancaster:
Thank you very much for your time yesterday on the phone. I have enclosed a more
detailed description of the process that I mentioned. Highlights of the process and
its development follow.
Process invented by Dr. Jeffrey Schwartz, professor of chemistry, and Dr.
Yumin Liu, postdoctoral fellow, Princeton University; research grant of
$1,000,000+ supplied by Texas Eastern Transmission Corporation
Patent issued to Princeton University, Sept. 6, 1994
Exclusive patent rights purchased by Xetex Corp., New York, NY, except for
Texas Eastern's right to use it to cleanup its own properties
Experimental results duplicated in tests by an independent laboratory
Bench-scale and preliminary pilot-scale testing of technology and
optimization of operating parameters currently underway at EPA Testing and
Evaluation Facility in Cincinnati under TSCA permit issued May 1995 by
EPA Region V
Pilot field test scheduled for late summer or early fall at Texas Eastern site in
west central Pennsylvania; PCB concentrations in soil used in pilot test will
range from 500 to 10,000 parts per million (ppm)
Process uses an off-the-shelf batch reactor with mixing, heating, and cooling
systems; exhaust system with activated carbon filter; and vacuum pump/vapor
condenser. Reactor will fit in the bed of a pickup truck.
E NVIRONMENTAL C ONSULTANTS
Warren County PCB Landfill
510622
August 4, 1995
Page 2
Dried soil containing PCBs is combined in the reactor with solvent, a catalyst,
a reducing agent, and an amine mixture in a nitrogen atmosphere at normal
atmospheric pressure in the reactor. Exposure limits, hazard recognition
signs, and personal protection requirements for these chemicals are attached.
The mixture is heated to between 230 degrees F to 275 degrees F and
maintained at that temperature for 2 to 6 hours. Reaction time is dependent
on the temperature and the PCB and reactant concentrations.
The reaction is then carefully quenched with water and cooled and the
solvent/water mixture drained from the reactor. Remaining vapors are
removed from the reactor with a vacuum pump and condensed.
The solvent/water mixture is distilled to separate it into a solvent/water
mixture containing biphenyl and reusable solvent. Biphenyl is readily
biodegradable.
The treated soil has benign by-products of the reaction such as titanium
dioxide, sodium borate (borax) and sodium chloride (salt). PCB
concentrations should be well below the hazardous waste level of 50 ppm.
Therefore, the clean soil can be left in place.
Costs for the process were estimated to range from $200 to $250 per ton by
General Electric Corporation in an independent cost analysis.
Please present this concept to the working group at your meeting next Wednesday.
Dr. Schwartz, Aquaterra, and Xetex would be pleased to make a more detailed
presentation to the group at your convenience. Thank you for your time and
consideration.
Sincerely,
AQUATERRA, INC.
YA';t/~~
Steven C. Lewis
Marketing Director
510622/SCL/pjc
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4.0 PROCESS AND TEST FACILITY DESCRIPTIONS
February 16, 1995
Version 1.0
The R&D activities that are being proposed under this permit application will be carried out in two phases.
Phase One will involve bench-scale experiments that will be carried out in a glass reactor on the order of
three liters. Experiments will be conducted using l 00 to 1,000 grams of PCB contaminated soil. The
primary goal of the Phase One activity is to determine the capability of the catalytic dechlorination process
to destroy PCBs in soil. The secondary goal of the Phase One study will be to establish a set of
optimalJviable operating conditions (reagent/soil ratios, time, temperature) and process configurations that
can be further evaluated and refined through Phase Two experiments.
Phase Two will involve preliminary pilot-scale tests which will be carried out in a reactor of size on the
order of ten cubic feet. Several pilot runs in a batch process mode will be performed using· approximately
l cubic foot ( or about 7 5 lbs) of PCB contaminated soil per run. The goal of the pilot study is to establish
a set of optimal operating conditions and procedures for field tests at the Armagh site.
4.1 Process Description
Dechlorination of polychlorinated biphenyls (PCBs) to biphenyl can be accomplished via a homogeneous
catalytic system which operates under mild conditions. Catalytic reduction occurs by an electron transfer
process, and reduction of individual congeners is facilitated by high chlorine content. A titanium complex
-Ti(III), is the active catalyst, and sodium borohydride is the ultimate reducing agent. Hydrolyzed
reduction reaction mixtures contain easily biodegradable organic components, sodium chloride, titanium
dioxide, and sodium borate.
A schematic diagram describing the batch catalytic PCB dechlorination process is shown in Figure 2.
Before treatment, the PCB contaminated soil must first undergo preparatory operations such as screening
and/or size reduction and homogenization followed by drying to remove moisture. Drying of the soil is
necessary to minimize consumption of the reducing agent, sodium borohydride, which reacts with water.
The solvent, diglyme, and the dried PCB contaminated soil are added to the reactor and mixed. Under
7
QC Figure 2. Schematic Diagram of the Catalytic PCB Dechlorination Process Stage I: Waste Feed Soil Preparation feed soil screening/ size reduction activated cart>on (lo atmosphere) solids dryer 1 • dry/ prepared waste feed soil hot air Stage II: Dechlorination Reaction @dry waste feed soil (D solvent (1) mixing (ON) r------® catalyst (solid) .----© reducing agent (solid) ,---(i) amines (liquid) activated cart>on ~---~ inert gas (to atmosphere) i~~~~as ® I reactor I @l heat (ON) Stage Ill: Reaction Quenching and Solvent Recovery @ mixing (OFF) @quench w/ water activated inert gas I carbon I (to atmosphere) inert gas (CONTINUE) reactor ®t l t@ heat (OFF) @ solvent cooling (ON) Stage IV: Solvent Rinse & Recovery @ mixing (ON) @ mixing (OFF) I .. I rinse w/ @ solvent =------. @ vacuum pump inert gas@ activated carbon inert gas (lo atmosphere) (OFF) ---~I reactor @ treated soil @ heat (ONi t t@ cooling @ heat (OFF) @ (OFF) solvent NOTE: Circled numbers define the chronology of the batch processing. ~ tt> a' .., C ~ ~.., tt> '< .., -~-a-.. 0 ~ ::, -\0 ->C 0 u, II "
February 16, 1995
Version 1.0
an inert atmosphere (nitrogen blanket) the catalyst (titanocene dichloride or Cp2TiC12), and the reducing
agent (sodium borohydride) are added to the reactor mixture. Next, an amine mixture (of N,N-
dimethyloctylamine and pyridine) is added to the reactor. Finally, while maintaining the inert atmosphere
inside the reactor, the contents are continuously mixed and heated. The temperature is maintained between
50 and l 50°C and the reaction is ~Bowed to proceed for a specified length of time. At the conclusion,
while still maintaining the inert atmosphere inside, the reactor is cooled to room temperature and water
is cautiously added to quench the reaction. Following quenching, the free water and solvent phases are
drained from the reactor. Biphenyl, which is highly soluble in the solvent and slightly soluble in water,
should be drained along with the free but mixed liquid phases. The treated soil is further rinsed with pure
solvent in order to remove residual biphenyl from the soil. The rinse solvent is drained and mixed with
the previously drained solvent. At this point the flow of inert gas through the reactor is stopped, and
using a vacuum pump, solvent vapors are pulled out of the reactor and condensed and recovered. The
drained solvent/water mixture is then distilled to recover a major portion of the solvent to be reused in
the process. The distillation residue (which should be a small fraction of the original volume) will consist
of a mixture of solvent and water containing the bi phenyl. The optimal end product of the reaction should
be solvent free soil with residual total PCB concentrations of less than or equal to l ppm. The treated
soil should also contain benign by-products of the reaction such as sodium chloride, titanium dioxide, and
sodium borate and very small concentration of readily biodegradable organic components such as bi phenyl
and amines.
4.2 Location of the R&D Facility
t to conduct the proposed R & D activities at the USEPA's T&E Facility 1
catalytic dechlorination proc
approaches for treating •
Figure 3 shows the location-of the T &E F • • . The T &E Facility is
ustrial wastes are evaluated. The
road spectrum of technological
1 l Creek Sewage Treatment Plant on land provided by the cit
20 y • Th~ T&E Facility is permitted by the USEPA and State of Ohio as a RCRA Treatment, Storage
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~ ~ .• .! Table 1. Exposure Limits and Recognition Quality Exposure limits IDLH Level (b) (a) (ppm) unless (ppm) unless Warning Ionization otherwise otherwise Concentration LEL (c) UEL (d) Potential Comvound indicted) indicated Odor (nnm) (%) (%) (EV) PCBs 0.5 mglm3 None Mild ----54% Chlorine Established Hydrocarbon Specialty /0 3500 Faint amine 0.47-/00 2.2 /5.2 9./2 Amine like Inorganic -Possible gas none ----Reducing evolution AJ?ent Catalyst --none ----Hydrogen --none -4 75 -(gas) NOTES: (a) OSHA Permissible Exposure Limit or American Conference of Governmental Industrial Hygienists (ACG/H) Threshold limit Value. (b) Immediately Dangerous to life or Health Level. (c) lower Explosive limit (d) Upper Explosive Limit "Tl ~ a-.., = ll,) <.., ~ '< .., -~-°' 0 ~ ::, -\C -\C 0 u, ·, 1'
~ tll Table 2 Acute and Chronic Effects and· First-Aid Treatment Compound Routes of Entry Eye Jrrita11t Acute Effects Target Organs PCBs Inhalation Yes Skin irritation, ch/oracne, eye Ski11, eyes, liver Ingestion irritation Skin and/or Eye Contact Specialty Inhalation Yes Eye & skin irritant, choking, CNS, liver, GI tract, Amine Absorption chest pain, nausea, convulsio11s eyes, skin lnRestion Inorganic Inhalation Yes Skin irritation, burning Skin, eyes, mucous Reducing Skin and/or Eye Contact isensatio11, coughing, shortness o, membranes, respiratory Agent breath, headache, nausea, tract vomitin~ Catalyst Inhalation Yes Irritant to skin and mucous Ski11, eyes, mucous Skin and/or Eye Contact membranes membranes, respiratory tract Hydrogen Inhalation explosion hazara Yes ~n high concentrations can act a. Skin, eyes, respiratory (gas) a simple asphyxiant tract Ge11eral First-Aid Treatment (A first-aid kit will be kept i11 the field trailer.) Eye -Irrigate immediately; a portable eye-wash unit will be kept in the field trailer. Skin Inhalation Ingestion -Soap wash promptly. -Moved to fresh air. -Get medical attention. "T1 ~ C" .., C: ti) <.., ~ ~ .., -~-O'\ 0 -::I -\0 -\0 0 u, ·, ..,
~ a-, Table 3 Health & Safety Monitoring and Action Levels Hazard Monitoring Action level Protective Measures Monitoring Schedule Method Toxic Vapors HNU ,. 1) Measurable above level D+ Monitor every J 5 (10.2 EV lamp) background based on (see Table 4) minutes/every sample or judgement of SSO up to retrieved OVA } DDm HNU J) Measurable above level C Continuous monitoring ( 10.2 EV lamp) background based on ( See Table 4) or judgement of SSO up to OVA 1-5 oom HNU 1) Measurable above STOP WORK (/0.2 EV lamp) background based on EVACUATE AREA or judgement of SSO up to NOTIFY HEALTH & OVA >5 ppm SAFETY MANAGER NOTES: ( J) The above levels are not solely based on the criteria for selecting levels of protection be the /9484 EPA Standard Operating Procedures, but also on the professional jiulgement and experience of the Site Safety Officer ( SSO ). l'T'l ti) O" .., C: Ii,) <.., ti)'-< .., -!!?. O'I 0 ~ ::, -'° -"° c::, U1 .. '<
I
1.
2.
3.
4.
Table 4
February 16, 1995
Version 1.0
Protective Equipment for On-Site Activities
Activity
I
Level
I
Protective Equipment
I
Oversight of operation D Long sleeve work clothes or coveralls,
steel-toe-safety shoes.
Hearing protection (foam ear plugs or
muffs l if necessarv
Sampling of reactor D+ Tyvek Saronex coveralls, chemical-
resistant gloves.
Handling of repartioning C Same as l plus,
agent, specialty amine, Splash goggles,
inorganic reducing agent, Organic vapor respirator
and catalyst
Operating the chemical C Same as 3 plus,
Hard hat,
Face shield, and
Joints between gloves and boots must be
taned
37
...
16.0 TEST DATA
February 16, 1995
Version 1.0
Through extensive research and laboratory tests the inventors, Ors. Jeffrey Schwartz and Yumin Liu, both
of Princeton University, New Jersey, have reported a new method for the conversion of PCBs to readily
biodegradable biphenyl. It involves reductive dechlorination and is accomplished through homogeneous
catalysis under mild conditions. The dechlorination catalyst is prepared in situ from the simple titanium
complex titanocene dichloride, and easy-to-handle sodium borohydride is the ultimate reducing agent.
Since hydrolyzed reaction product mixtures contain only readily biodegradable organic components,
sodium chloride, titanium dioxide, and sodium borate, this method may be both chemically and
environmentally benign. Results of this fundamental research effort has culminated into a Patent (Number:
5,345,031) which was issued on September 6, 1994 by the United States Patent Office to The Trustees
of Princeton University, Princeton, New Jersey. A copy of the Patent is presented in Appendix B for
reference.
The subject process is based on the discovery that by conducting the reaction in the presence of an
aliphatic or aromatic amine, the scope of the reaction can be expanded to other halogenated compounds
and a greater degree of dehalogenation can be achieved. The reaction is conducted in an inert solvent
such as diglyme. The reaction can be conducted at temperatures of from about 50°C to about 150°C.
Reaction times depend on the reactants and temperature. Operating at, for example, 125°C, <:omplete
dehalogenation has been observed in less than 10 hours.
The following examples will serve to further typify the nature of the invention.
Aroclor® 1248 is a common PCB mixture which contains a substantial fraction of environmentally
persistent tetra-, penta-, and hexachlorinated congeners, and therefore it has been an especially significant
mixture for reductive dechlorination studies. Since the more heavily chlorinated congeners are
preferentially reduced, the initially complex mixture of PCBs not only undergoes global dechlorination.
but congener mixtures remaining after only short processing times fall within the distribution of easily
aerobically biodegradable species.
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February 16, 1995
Version 1.0
Reduction of pure Aroclor® 1248. In a typical procedure, a solution of Aroclor® 1248 (1.0 gm; 13.7
mmol chlorine) in triglyme (20 ml) was heated at 125°C with Cp2TiCl2 (171 mg; 0.687 mmol; 0.05 equiv .
per Cl), NaBH4 (622 mg; 16.44 mmol; 1.2 equiv. per CL), pyridine (0.68 ml; 8.4 mmol; 0.61 equiv. per
Cl) and N,N-dimethyloctylamine ( 1.73 ml; 8.4 mmol; 0.61 equiv. per Cl). After further heating (total time
2 hrs), the product mixture contained ca. 50% biphenyl and ca. 50% monochlorobiphenyls (primarily 3-
chlorobiphenyl). After 24 hours, complete reduction to biphenyl was observed.
Reduction of Aroclor® 1248 from contaminated soil. High "organic content" garden soil (10.2 gm) was
heated at 90°C to remove superficial water and was then spiked with Aroclor® 1248 (1.05 gm; 14.8 mmol
C-Cl; 9.3% PCB by weight). The soil sample was then suspended in 20 ml of diglyme and treated
similarly as described above for pure Aroclor® 1248. In particular, the suspended soil was heated at l 25°C
with Cp2TiC12 (171 mg; 0.687 mmol; 0.05 equiv. per Cl), NaBH4 (822 mg; 21.7 mmol; 1.47 equiv. per
CL), pyridine (0.68 ml; 8.4 mmol; 0.57 equiv. per Cl) and N,N-dimethyloctylamine (l.73 ml; 8.4 mmol;
0.57 equiv. per Cl). A mixture containing ca. 50% biphenyl and ca.SO% 3-chlorobiphenyl was obtained
after 24 hrs of treatment. Acknowledging the possible presence of residual water and reducible soil
components, a freshly dried and spiked soil sample (10.2 gm soil; 1.02 gm Aroclor® 1248; 14.4 mmol C-
Cl; 9.1 % PCB by weight) was heated at 125°C in 20 ml of diglyme in the presence of Cp2TiC12 (366 mg ;
1.47 mmol; 0.10 equiv. per Cl), NaBH4 (l.335 g; 35.28 mmol; 2.4 equiv. per Cl), pyridine (1.43 ml; 17 .7
mmol; 1.2 equiv. per Cl) and N,N-dimethyloctylamine (3.63 ml; 17 .7 mmol; 1.2 equiv. per Cl). After 12
min, a mixture .:onsisting only of dichlorobiphenyls (ca. 70%) and monochlorobiphenyls (ca. 30%) was
obtained. After further heating (total time 2 hr), only biphenyl was observed.
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20.4 Installation of the PCB Destruction System
February 16, 1995
Version 1.0
The primary component of the PCB destruction system is a mixed-phase stirred reactor. The eactor for
Ph e One bench-scale tests is of a fairly simple design. The reactor consists of a 3 Ii round bottom
resin fla built of glass. The flask has a removable five-necked cover (four in a uare formation and
one in the ce r). The following steps will be followed to install the reactor.
1. Through the c ter neck of the flask cover a shaft (built of tern red glass) driven by an overhead
motor is installe Collapsible teflon paddle blades are at ched to the lower end of the shaft.
The cover is then s ured onto the flask bottom using d icated clamping device.
2. Through one of the out necks a thermocouple is • _stalled to monitor the temperature of the
reactor contents.
3. To another neck a water cooled flux conde er is attached. This condenser will condense any
solvent or other condensible vapo that ay be generated inside the reactor and return the
condensate back into the flask.
4. Through a third outer neck an inert as su ly line will be connected. Note: during the reaction
the inert gas will be flowing thr gh the rea r and exiting through the reflux condenser.
5. The condenser outlet will be nnected with a flex · le tubing to an activated carbon canister. The
canister outlet will be con cted with a flexible tubi , the end of which will be immersed below
water in a beaker. Note· when the reaction is in progres the inert gas flowing through the system
will bubble through e water in the beaker indicating ositive inert atmosphere inside the
reactor.
6. The fourth ou r neck will be used to load the soil, solvent, and ther reagents and catalyst into
the reactor. is neck will also be used to draw samples of the rea or contents for analysis. A
stopper I be used to keep this neck sealed closed when not being ed.
7. A he ing mantle or a constant temperature oil bath equipped with a tern ature controller will
be sed to heat the flask bottom in order to heat and maintain the reactor conte ts within a desired
emperature range.
e Phase Two system is expected to have a 3 cubic foot sized reactor and will be conceptually operated
similar to the Phase One system.
20.5 Process Operation
Under the subject investigation the catalytic/chemical PCB dechlorination reaction will be carried out in
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February 16, 1995
Version 1.0
a batch processing mode. A schematic diagram describing the batch catalytic PCB dechlorination process
is shown in Figure 2. (Operator(s) of the system shall pay special attention to the chronology of the
steps involved in the batch processing.) Following the preparation of waste feed soil and the installation
of the system as described in Sections 20.2 and 20.4 above, the operator(s) will follow the chronological
steps outlined below as part of the procedure for operating the batch process.
l. The solvent, diglyme, and the dried PCB contaminated soil will be added to the reactor.
2. The mixer will be turned on.
3. Dried waste feed soil will be added to the reactor.
4. Inert gas (nitrogen, for example) supply will be turned on.
5. Add the catalyst (titanocene dichloride or Cp2TiC12) to the reactor.
6. Add the reducing agent (sodium borohydride) to the reactor.
7. Add the amine mixture (of N,N-dimethyloctylamine and pyridine).
8. While maintaining the inert atmosphere and mixing inside the reactor, heat the reactor content,
by either lowering the round bottom resin flask into an oil bath or a heating mantle in Phase One
testing, or by turning on steam supply to the reactor heating jacket in Phase Two testing.
Maintain the reaction temperature to a specified level using the feedback temperature controller.
9. The reaction is allowed to proceed for a specified length of time. Then remove or tum the heat
supply off.
10. Cool the reactor content to room temperature, by either replacing the oil bath or the heating
mantle with cooling water bath in Phase One testing, or by replacing the steam in the reactor
jacket with cooling water supply.
11. Add a very small amount of water to the reactor to quench the reaction. Not: the inert gas supply
should still be on. cess reducing agent (sodium borohydride) will be consumed by the reaction
with water which will result in the generation of hydrogen. Hydrogen will be diluted by the inert
gas and purged out the reactor.
12. Tum off the mixer.
13. Drain all the free liquid from the reactor (i.e., solvent and water).
14. Turn the cooling off.
15. Add rinse solvent to the reactor.
16. Turn on the mixer.
17. Turn off the inert gas.
18. Tum off the mixer.
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February 16, 1995
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19. Drain all the free liquid from the reactor.
20. Heat the reactor content, as in step 8, to strip off the residual solvent from the soil.
21. Solvent vapors are condensed, but this time are collected outside the reactor.
22. Tum the heat off.
23 . Allow the treated soil to cool off in the reactor and then unload it from the reactor.
76