Document 2xX1jL7ZVeLZowGwyz747aKN

Lake Charles VCM Plant CERTIFIED WAIL #8094944 RETURN RECEIPT REQUESTED May 4, 1983 Conoco Chemicals Company A Division of Conoco Inc. P.0. Box 605 Westlake, LA 70669 o^*Cc* C tj VcD (318) 491-5211 TO: Mr. Greg J. Gasperecz Air Compliance Division Department of Natural Resources P 0 Box 44066 Baton Rouge, LA 70804 FILE: ! ________ Dear Mr. Gasperecz: This letter is in response to your questions concerning the Conoco VCM Plant's semi-annual report (dated March 15, 1983) on vinyl chloride emissions as required by Section 61.70 of the Vinyl Chloride National Emission Standard for Hazardous Air Pollutants. On January 17 and February 19, 1983 the 24-hour average for vinyl emissions in the oxychlorination reactor vent exceeded the 0.2 gm/Kg of EDC limit. Both excursions were caused by difficulties with Qxychlorination reactor train during startup of the system. The difficulties in both cases were caused by two unique catalyst performance problems which have since been corrected by the conversion to 02-based oxychlorination and by catalyst change-out. On both days, the Qxychlorination section operated for less than 4 hours. Thus the excursions during this short period of operation in excess of the 0.2 gm/Kg limit caused the "24 hour" average to also exceed 0.2 gm/Kg. Your second question concerned the VC emissions rate during the December 12, 1982 incinerator bypass. Table I lists the estimated emissions per hour for this time period. This estimate is based on an engineering evaluation completed for the Oo-oxy conversion and prorated for 1.6MM lbs/day production rate on December 12, 1982. If you have any further questions, please contact Ron Bryan at (318) 491-5062. Sincerely VCM Plant Manager br cc: Mr. William H. Taylor, Jr. U.S. EPA Region VI Mr. Joe Withers Southwest Regional Office bcc: JWW-RB-MLA-PLF-DLD-MWC-JCL-BIR-ESW-MGH 00024o44 TABLE I Typical Vinyl Chloride Emissions (1) During an Incinerator By-pass Vent Source Direct Chlorinator Vent Light Ends Column Vent Tank Farm Vent Total VCM Vent Rate Ibs/hr (2) 2.74 15.85 .76. 19.35 Notes 1) The typical VCM emissions corrected for VCM production rate are calculated as follows: VCM Vent Rate Corrected for Prod. _ Total Vent VCM Flow x Concentration x VCM Production in MM Lbs./Day ' 271 The total vent flows and VCM concentrations were obtained from the projected Modernization Material balance at full VCM production rates (2.1MM Lbs./Day). 2) Corrected for the 1.6MM lb of VCM/day production rate on December 12, 1982. VVC 0000X4045