AQ_F_0800044_20170816_ST_RvwMemo (4)

DIVISION OF AIR QUALITY
August 16,2017
MEMORANDUM
To: Robert Fisher,Washington Regional Office
From: Brent W.Hall,Stationary Source Compliance Branch(SSCB)&ll-
Subject: Avoca,Inc.
Facility ID 0800044,Air Permit No.01819T47
Merry Hill,Bertie County,North Carolina
HAP Compliance Testing for ES-4000-WW Operations,DAQ Tracking No.2017-116ST
Performed by Air-Tech Environmental June 6,2017
Air-Tech Environmental(Air-Tech)performed EPA Method 18 to determine organic HAP emissions from
Sclareolide operations,ID No.ES-4000-WW(SDE-2). The test was the initial hazardous air pollutant(HAP)
compliance test for the Sclareolide operations. The test results demonstrate compliance with the applicable
regulations at the test conditions discussed below.
SDE-2 includes one chilled water condenser(ID No. CD-4002)in series with a mineral oil scrubber(ID No.
CD-4003-S)controlling emissions from the following:
• One 17,900 gallon virgin solvent tank(ID No.T-4001);
• Two 6,000 gallon process tanks(ID Nos.T-4017 and T-4018);
• Three 4,200 gallon reactors with process condensers(EX-4001)(ID No.R-4004),(EX-4002)(ID No.R-
4005),and(EX-4003)(ID No.R-4044);
• One 1,500 gallon reactor(ID No.R-4015);and
• One centrifuge(ID No.C-4001)
40 CFR 63 Subpart FFFF National Emission Standards for Hazardous Air Pollutants:Miscellaneous Organic
Chemical Manufacturing applies. In accordance with Table 2 of 63 Subpart FFFF, Section 2.2.C.q of the permit
states"the Permittee shall reduce collective uncontrolled organic HAP emissions from the sum of all vents within
SDE-2 operations by>95 percent by weight by venting emissions from a sufficient number of the vents through one
or more closed-vent systems to the chilled water condenser(ID No.CD-4002)in series with the mineral oil scrubber
(ID No.CD-4003-S)." EPA Method 18 was performed at the inlet and outlet of the scrubber. The removal
efficiency results from the SDE-2 process are summarized in the table below.
Pollutant Average Removal Removal Efficiency Regulation Compliance
Efficiency Limit
Hexane 98.9% >95% 63 Subpart FFFF Yes
Air-Tech measured hexane at the inlet and outlet of the scrubber.Due to sampling location issues,it was not
possible to perform EPA Method 2 flow measurements. Air-Tech attempted to use methane spiking for flow
measurements,but was unsuccessful. Therefore,removal efficiency is based on concentration values. Since Air-
Tech did not obtain valid flow measurements,the hexane mass emission results are not acceptable.
Avoca,Inc proposed alternative monitoring of various process parameters to establish optimal operation of the
process. The subsequent DAQ approval of alternative monitoring established a maximum temperature of 105°F for
the air entering the absorber. It should be noted that the average temperature for the air entering the absorber
during testing was 78.22'F. The SDE-2 HAP emissions control efficiency demonstrate compliance with the
applicable regulations at the tested conditions. If there are any questions regarding this review,please contact me at
[phone] or [e-mail].
cc: Central Files,Beaufort County IBEAM Documents-0700071