Document LgJQqxL6KaE5ynQ287eNYMBjw

Vista Chemical Company Lake ChaHes VCM Plant VCM Plant Rd., 90. Box 605 CERTIFIED KAIL # P 440 213 840 RETURN RECEIPT REQUESTED December 28, 1990 NAfosHake, Louisiana 70669 Phone (318) 494-5000 bcc: RAC SAR PJK SAW GWB(VCM) MGH JLJ (LCCP) JCL DLC (Hous) Dr. Michael McDaniels Office of Air Quality Department of Environmental Quality p o Box 44096 Baton Rouge, LA 70804-4096 Res comments on Draft Section 5121 subchapter F. vinyl Chloride Dear Dr. McDaniels: Vista Chemical Company would like to thank you and the Department for the opportunity to review and comment on this proposed regulation, and to discuss how it will affect our operations. Vista runs and operates an Ethylene Dichloride and Vinyl Chloride manufacturing facility at its Westlake, Louisiana Chemical works. These facilities would be severely impacted by a portion of this proposed rule in a way that will produce no positive benefits for the environment. In fact, it would prevent Vista from operating in an environmentally sound method, proven by past performance. Vista requests that the "exhaust gas mixing" clauses be deleted from this proposal, as explained in the following sections. Section 5121" Emission standard for vinyl Chloride", contains several problematic statements. The first is Part c.i. which concerns Ethylene Dichloride Purification. It states that, "No exhaust gas stream having greater than 10 ppm of vinyl chloride shall be mixed with any gas stream having less than 10 ppm of vinyl chloride." Additionally Part D.2.' which concerns the Vinyl Chloride Plant Emission Standard states the exact same language. Vista's first comment regarding these two sections is that this language is not required by the Federal Emission Standard, and we believe, for due cause. It is our understanding that the Department has proposed this language in order to prevent compliance with the 10 ppm emission standard by dilution. We agree with this concept. No emission standard should be achieved by dilution - a significant reduction of the total_mass of pollutants (Vinyl Chloride or Ethylene Dichloride) should be achieved. Vista VVV 000026597 disagrees, however, that this is the proper approach to addressing this concern. Secondly, Vista does not believe that this is a bonefied problem at vinyl or ethylene dichloride production facilities. Only four exhaust gas streams are consistently less than 10 ppm vinyl and combined with the other vent gases. These four are intermittent sources venting only periodically during the year. They do contain significant amounts of ethylene dichloride for which incineration provides good control. An additional 24 other major sources are vented to the plant incinerators. Of these, almost half vary in concentration and are sometimes greater than 10 ppm Vinyl Chloride and at other times less than 10 ppm. Most of these contain significant amounts of ethylene dichloride and other chlorinated organics compounds, for which it is best to be controlled by incineration. This means that only a few less than 10 ppm vents, which are intermittent, contribute to the total flow of vents, and that these do not significantly affect the performance of the control equipment. In addition, the fact that a good portion of the gas vent streams swing above and below 10 ppm of vinyl chloride makes it extremely difficult and prohibitively costly to segregate these vents -on a concentration basis. Continuous analyzers would be needed on each vent, and controls which would shunt the vents to the proper incinerator. The changing vent flows would make incinerator operation almost impossible and would drastically increase the number of bypasses. Two additional incinerators would be needed and have been estimated to cost between 5 and 10 million dollars. This would be a duplication of existing duplicate incinerators. Additional incinerators would also increase other pollutant loading such as NOx, CO, etc. without providing any real reductions of the target pollutants. Vista's existing system burns all of the process vent gases together, and achieves better than a 99.7% destruction efficiency. This is on a mass basis - not concentration. In addition this is done with relatively few bypasses due to malfunctions. Actually, this proposed rule could be understood to prevent the utilization of combustion air in the incineration process, because it is a gas stream with less than 10 ppm vinyl chloride. This would, of course, prevent incineration as a treatment option. Combustion air, provides for completion combustion of the target pollutants. Even at a modest 20% excess air ratio, it takes about 6 times the volume of air and fuel gas to the exhaust gas flow for proper combustion. This results in a true reduction of the mass of .target pollutants by 99.7%.. Clearly this is not achieving the 10 ppm standard by dilution. A rule which would force the segregation of vvv o 00026598 existing vent systems needlessly, provide no additional reduction of target compounds, and actually increase emissions of other pollutants is not desirable, nor in anyone's best interest. In light of these issues Vista respectfully requests that the Department delete these statements from the proposed regulations. If you have any questions or comments, please call me at (318) 494-5031. Sincerely, D. R. Booth Sr. Environmental Coordinator da(C3) cc: Chris Roberie - LDEQ Baton Rouge VVV 000026599