Formosa Plastics Corporation, LA - Executive Summary |
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2694 LDEQ Facility ID Number EXECUTIVE SUMMARY Facility Description: Formosa Plastics, LA, located in Baton Rouge, is a producer of basic industrial chemicals and materials. Chlorine, sodium hydroxide, hydrogen, ethylene dichloride, anhydrous hydrogen chloride, and vinyl chloride are the major materials produced at the facility. The primary commodity produced at the facility is polyvinyl chloride resin. Polyvinyl chloride is used to manufacture food wrap, children's toys, medical devices, garden hoses, piping, vinyl siding, floor tiles, roofing shingles, electrical wiring insulation, furniture, clothing articles, automotive parts, etc. The facility is certified to ISO 9002 and 14001 international quality and environmental management standards and employs approximately 373 people and 130 full-time maintenance contractors. The Baton Rouge plant consists of five operating units; four of which are covered under the Risk Management regulation. These are Chlor-Alkali (CCN), Polyvinyl Ch loride (PVC), Vinyl Chloride Monomer (VCM2), and Ethylene Dichloride/Vinyl Chloride Monomer (EDC/VCM). A description of the four covered processes is included in this summary. RMP-Covered Materials: The facility has five RMP-covered materials on site exceeding the RMP-specified regulatory threshold quantities. These materials are chlorine, anhydrous hydrogen chloride, anhydrous ammonia, vinyl chloride, and propylene. Chlorine is a greenish-yellow gas; it's heavier than air; it has the strong odor of household bleach; it is corrosive. Chlorine is used as a drinking water disinfectant; making household bleach; making plastics and other chemicals. Formosa manufactures and uses this material in the production of ethylene dichloride. Vinyl Chloride monomer is a colorless gas; it is heavier than air; it has a pleasant odor; it is flammable. Formosa manufactures and uses this material in the production of polyvinyl chloride. Anhydrous Hydrogen Chloride is a colorless gas; it is heavier than air; it has an irritating, pungent odor; it is corrosive. It is used in food processing and brewing operations, metal treatment for electroplating, rubber manufacture, metal ore extraction and reduction, leather manufacture, plastic and resin production, etc. Formosa produces this material in the vinyl chloride manufacturing process. Anhydrous Ammonia is a colorless gas; it is lighter than air; it has the strong odor of household ammonia; it is corrosive and flammable. Anhydrous Ammonia is used in manufacturing fertilizers, textiles, pulp/paper processing, pharmaceuticals, pesticides, explosives, rocket fuel, dyes, photography/blueprinting, household cleaners, and is used as a refrigerant. Formosa uses this material as a neutralization agent. Propylene is a colorless gas; it is heavier than air; it is flammable; it is virtually odorless. Propylene is used as a refrigerant and in the manufacture of plastics, antifreezes, and food additives. Formosa uses this material as a refri gerant. Accidental Release Prevention Policy: The facility's commitment to the safety of its employees, the community and the environment is exemplified by their EHS policy statement. The facility recognizes that we operate under privilege and acknowledge that protection and safety of the environment, community, and our employees is integral to our continued success as an organization. As such, a holistic approach consisting of sound design, engineering and administrative measures is utilized in preventing accidental releases. Accidental Release Prevention Programs and Measures: In the prevention of accidental releases, the facility employs numerous engineering and administrative controls to ensure the chance of a hazardous material release is minimized. Engineering controls utilized include, but are not limited to conservative process design safety factors, check valves that limit/prevent releases in the event of reverse/excess flow, pressure and level alarms on primary storage v essels, redundant level detection for overfill protection, relief valves to prevent vessel overpressurization, insulated vessels to prevent solar overpressurization, neutralization/absorber systems to control pressure, on-line pH monitoring/alarm system for early detection of process equipment failures, automatic/manual valves to isolate/limit releases, and redundant mechanical seals to prevent leaks. Administrative controls utilized include certification to ISO 9002 and 14001 international quality and environmental management standards, Process Safety Management programs, Safety Permitting programs, Hot Work Procedures, Hazardous Energy Control programs, regular equipment inspections and maintenance, Preventive Maintenance programs, Standard Operating and Troubleshooting procedures, training programs, standards for overfill protection, VOC emissions monitoring program, etc. Emergency Response Policy: It is the policy of the facility to prevent, minimize, control, and mitigate accid ental releases. The facility recognizes that quick response to an incident is instrumental in assuring protection of the environment, community and our employees. To assist with this the facility utilizes numerous engineering and administrative controls for early detection, communication, and response to incidents. Emergency Response Programs and Measures: The facility employs numerous engineering and administrative controls to ensure the chance of a hazardous material release is minimized. Engineering controls which aid in the identification and/or communication of such incidents including atmospheric leak detection systems, portable hand-held atmospheric detection equipment, facility alarm and siren systems, public address systems, and portable hand-held two way radios. Administrative controls include an Emergency Response plan, Spill Prevention plan, Emergency Notification procedures, and Emergency Shutdown procedures. An annual drill, designed to test the execution of the respon se plan and the communication procedures, is conducted yearly. A critique is held following the event. The facility belongs to a hotline network, through which a system is in place to notify our immediate industrial neighbors and emergency response agencies with a single phone call. Upon notification the agencies can activate the community alert siren and auto dialer systems as necessary to notify the public of the proper actions to take. The hotline system is tested on a daily basis; the community alert system is tested on a monthly basis. Emergency preplanning and response coordination with external agencies and responders is accomplished via membership in and participation with organizations such as the Baton Rouge Area Mutual Aid Society, North Baton Rouge Emergency Response Task Force, and the Local Emergency Planning Commission. Fixed fire suppression systems, consisting of three 4000 gpm fire water pumps, approximately 85 fire hydrants and hydrant/monitor assemblies, water d eluge systems, and foam blanket systems on specific storage vessels help protect the facility in the event of fire. Additionally, there are approximately 35 fire hose houses which contain fire hose, fire water nozzles, and various wrenches and adapters that provide mobile fire fighting capability. Additional fire water capacity can be accessed through a neighboring industry's fire water system as needed and/or required. For hazardous materials incidents a supply of emergency equipment is kept on-hand, including protective clothing, fresh air systems, capping kits, absorbent pads, leak dams, etc. For incidents requiring external assistance, manpower is provided by the Baton Rouge Fire Department. The facility can also use the services of contract leak mitigation services as required. Release Scenarios: Worst Case Flammable - The facility chose a storage vessel full of vinyl chloride as it's worst case flammable scenario. This selection was based upon the size of the largest vinyl ch loride storage vessel. The vessel was assumed theoretically full of product. No safeguards or mitigating factors, including administrative controls, were assumed or used in the quantity determination. The endpoint distance was calculated using EPA's OCA Guidance Reference Tables or Equations. Population estimates were conducted using Landview III. Public and Environmental receptors were determined using a combination of Landview III, USGS maps, and local maps. Alternate Case Flammable - The facility chose a gasket failure on a vinyl chloride scrubber as it's alternate case flammable scenario. This selection was based upon an actual event. During that incident about 10,000 pounds of vinyl chloride were released and did not explode. In modeling the alternate case scenario, the same quantity of vinyl chloride was used, and the material was assumed to form a cloud, find an ignition source, and explode. The endpoint distance was calculated using EPA's OCA Guidance Reference Tables or Equat ions. Population estimates were conducted using Landview III. Public and Environmental receptors were determined using a combination of Landview III, USGS maps, and local maps. Worst Case Toxic - The facility chose a storage vessel full of chlorine as it's worst case toxic scenario. This selection was based upon the size of the largest chlorine storage vessel and the maximum endpoint distance of the material. The vessel was assumed theoretically full of product. No safeguards or mitigating factors, including administrative controls, were assumed or used in the quantity determination. The endpoint distance was calculated using EPA's OCA Guidance Reference Tables or Equations. Population estimates were conducted using Landview III. Public and Environmental receptors were determined using a combination of Landview III, USGS maps, and state/local maps. Alternate Case Toxics - The facility chose three alternate case toxic scenarios in accordance with the RMP rule. The events selected were based upon a combination of actual and theoretical events for chlorine, anhydrous hydrogen chloride, and anhydrous ammonia. The endpoint distance for each was calculated using EPA's OCA Guidance Reference Tables or Equations. Population estimates were conducted using Landview III. Public and Environmental receptors were determined using a combination of Landview III, USGS maps, and local maps. Five Year Accident History: The facility has had numerous releases within the last five years which were reported to agencies in accordance with various regulatory requirements. This information is currently a part of public record. One of these releases requires RMP reporting within the criteria specified by the Risk Management rule. The incident involved a release of chlorine in which one facility employee was hospitalized. Planned Changes to Improve Safety: The facility operates under a credo of continuous improvement in every aspect of operation. This is exhibited in the magnitude of cap ital improvement proposals which are either approved or in the evaluation/planning phases. As examples, the facility is examining the feasibility of eliminating liquid chlorine inventory from the site. Currently in progress are projects to provide a well-trained internal fire brigade and hazardous materials response team. While the facility historically has depended upon external sources for these services, internal response measures will further improve our ability to mitigate an incident in a timely manner. Other planned projects include improvements in ambient air monitoring and computerized process control systems. Facility RMP-Covered Process Unit Descriptions: Caustic/Chlorine (CCN) Unit Process Description The Caustic/Chlorine unit manufactures chlorine, sodium hydroxide, and hydrogen, using asbestos diaphragm technology. The caustic/chlorine production process consists of reacting sodium chloride brine in electrolytic cells to produce chlorine gas, hydrogen gas, and a wea k liquor consisting of a solution of caustic soda and salt. The chlorine gas is purified, and used totally in-house at the facility to produce 1,2-dichloroethane (ethylene dichloride, EDC). The hydrogen is cooled and compressed before being sold to an off-site customer's compressor station, PRAX Air Corporation (PAC), via piping the hydrogen to PAC's off-site compressor station. A side stream is sent to the VCM units for internal consumption. The weak liquor is sent to the evaporator train to remove most of the salt and concentrate the caustic to 50% prior to being sent to storage tanks. The caustic solution is then shipped off-site as a product to customers via barges, trucks, rail cars, ships, and pipeline. The unit receives crude salt brine from off-site via a pipeline. The brine is purified to remove calcium and magnesium. The brine is then saturated with sodium chloride salt from the evaporators before being fed to the cells. The electrolytic cells are located in two large cell rooms in which direct electrical current is used to produce chlorine gas at the stable anode. Ionized brine migrates through a permeable asbestos diaphragm to the cathode where hydrogen gas is produced. The remaining liquid is a weak liquor consisting of 12% caustic soda and 16% salt solution. The weak liquor is either drawn off and stored, or fed directly to the evaporators. Chlorine gas is introduced into coolers to remove moisture. The gas is then sent through a wet brinks mist eliminator to remove residual water. Additional water is removed by passing the chlorine gas through sulfuric acid drying towers. The residual acid is used for pH neutralization at the caustic plant's water treatment system. Sulfuric acid mist is removed by a dry brinks mist eliminator. The chlorine gas is then fed to a scrubber to be cooled and remove impurities. After final filtration, the cold chlorine gas is compressed to 100 - 150 psig. The compressed gas is then partially liquefied in exchangers with the remaining gas being sent via a pipeline to the EDC plant. Liquid chlorine is stored in two tanks until needed for the scrubber. The weak liquor is fed to triple effect evaporators where the caustic content is increased to 50% through removal of water. The salt content is reduced from 15% to 1.2% through treatment by a series of centrifuges. Most of the salt is recycled back to the process to produce saturated brine. Some of the salt is disposed of to remove impurities. The 50% caustic solution is sent to storage tanks before being shipped off-site as a product. Some of the caustic solution is diluted to 25% and is shipped off-site via pipeline, tank trucks, or rail cars. Ethylene Dichloride/ Vinyl Chloride Monomer (EDC/VCM ) Unit Process Description The VCM I unit produces approximately 675 net tons per day of vinyl chloride (VCM). Gaseous ethylene and chlorine gases are received via pipeline, and are sparged into liquid EDC in a vertical, open pipe rea ctor. The heat of the reaction is removed by a vertical heat exchanger. Circulation is provided by a thermosiphon effect resulting from the differences in the liquid density of the two sections. Produced EDC is removed via an overflow line to a wash train, where neutralization occurs, and impurities are removed. The water which is used to remove the impurities is sent via hard pipe to the EDC/VCM I unit wastewater treatment system. Emissions from the reactors consisting of inert gases, unreacted ethylene, and EDC vapors are piped to the plant's incineration system, where hydrocarbons are destroyed and chlorine is recovered as hydrochloric acid (HCl). Pure EDC is fed to the natural gas fired cracking furnaces. About 50% of the EDC is cracked to VCM and HCl. Furnace product output is partially condensed in quench columns. The quench effluent passes to the HCl column where pure HCl is removed at the column overhead, and is later fed to the oxychlorination reactor. EDC and VC M from the bottom of the column is fed to the vinyl column. VCM from the overhead of this column then goes to HCl scrubbers and a drying tower for final polishing. VCM is stored in pressure spheres before being sent to the PVC plant. EDC from the bottom is fed to the EDC purification train. The HCl and VCM columns normally do not vent. However, during upset conditions, the can vent to the emergency vent system. In the oxychlorination section, HCl produced by the cracking furnaces is reacted in the presence of a catalyst with ethylene, piped in from off-site, and oxygen. The products of the reaction are EDC and water. The heat of the reaction is removed by heat exchanger tubes and removed in a steam drum. The steam is utilized in the purification section. Reaction gases pass through a recovery section where crude EDC is condensed and sent to storage tanks prior to purification. The water is returned to the hot quench where EDC is stripped before the process wastewater is sen t to the biological wastewater treatment plant. Unreacted gases are piped to the unit's incinerators. One incineration unit is capable of incinerating at a rate of 60 MMBtu/hr, and the other on at a rate of 48 MMBtu/hr. This system is designed to oxidize the organic components from the vents from the closed process streams, cool the products of combustion in a waste heat recovery boiler, and remove and neutralize the HCl formed during the combustion process. Traditional distillation columns, with reboilers and reflux condensers, are used to remove impurities from recycle and oxychlorination reactor EDC. Two light ends columns remove water and EDC. The process water is sent to bioplant water treatment strippers, and the vented light ends are piped to the plant's incinerators. The bottoms from the light ends columns are pumped to the heavy ends column for removal of heavy ends. The VCM I process waste water treatment system consists of hard pipe, a phase separator, a neutrali zer system, two process waste water storage tanks, and two waste water steam strippers. EDC and VCM contaminated process waste water streams from the VCM I and VCM II plants are piped to the phase separator to remove the EDC phase from the waste water. The EDC phase is piped to the wet crude EDC storage tank. The waste water is pumped to waste water storage, pH adjusted, and then steam stripped of TOC, including EDC and VCM. Gases and vapors from the overhead of the steam stripper passes through a condenser. Non-condensible gases are piped to the plant's incinerators. The condensed EDC is piped to the wet crude EDC storage via the phase separator. Vinyl Chloride Monomer (VCM II) Unit Process Description The VCM II unit is capable of sustaining the necessary VCM (Vinyl Chloride Monomer) production of an average 1350 ton/day to feed the PVC plant on site. Pure EDC is fed from the Pure EDC Storage Tank to three gas fired cracking furnaces. An approximate conversion of 50 to 55 % EDC to VCM and HCl is achieved in the furnaces. The furnace effluent is fed to quench columns where it is partially condensed. Quench vapor and liquid is fed to the HCl distillation column where anhydrous HCl is removed from the Column overhead. EDC and VCM from the HCl column bottoms is then feed to the VCM distillation column. Recycle EDC from the bottom of the VCM column is reacted with chlorine to remove chloroprene and then stored in the Recycle EDC Storage Tank. Product VCM from the overhead of the VCM column is further purified in the HCl Stripping Column before being sent to the storage spheres. VCM stored in the spheres is transferred to PVC and also loaded in rail tank cars. Anhydrous HCL removed in the HCl Column is stored in the HCl Storage Sphere and fed to three Oxychlorination reactors. It is reacted in the presence of oxygen, ethylene and a catalyst to produce EDC and water. The heat of reaction is removed and the reactor temperature controlled by series of exchanger tubes which pass through the reactor. The steam produced is fed to the VCM II low pressure steam header. The Oxychlorination Reactor product is quenched with condensed liquor. The condensed EDC and water from the quench operation are then separated. The EDC contaminated water is sent to the process waste water storage tanks. Unreacted components are further cooled to remove EDC and unreacted products plus inerts are recycled back to the reactor. A purge stream of non-condensable gases is vented to the incinerator to control reactor pressure. The EDC Purification section purifies EDC before it is fed to the cracking furnaces. The main pieces of equipment in this area are the two Light Ends Columns, the Heavy Ends Column and the EDC recovery column. Import EDC is received from the storage tank, T-80B located in VCM I unit. This EDC is purified in one of two Light Ends distillation columns to remove light components, consisting mainly of water. The VCM II unit is als o capable of receiving and purifying crude EDC from VCM I unit. This EDC, and EDC from the Recycle and Wet Crude EDC Tanks, are purified in the Light Ends and Heavy Ends Column. The Heavy Ends Column removes components heavier than EDC. The bottom product of this column is further purified in the Tar Stills and EDC Recovery Column to recover EDC and lower the concentration before it is disposed of as Heavy Ends Waste. The Heavy Ends is stored in tanks and removed from the plant site via tank trucks. Lights and inerts which are removed, by pressure control, in the Light Ends, EDC Recovery Columns, and Heavy Ends Columns are fed to the Incinerators through the vent system. All purified EDC from this section is stored in the Pure EDC Storage Tank. Water removed in the Light Ends Columns, produced in the Oxychlorination reactors and from other sources throughout the plant that are contaminated with EDC are contained by the process waste water collection system in storage tanks. Thes e tanks are used to store and separate the EDC from the waste water. The EDC recovered is pumped to the West Crude EDC Tank. The waste water is pumped to the VCM I unit where the EDC is steam stripped from the waste stream. VCM II unit has two incinerators which receive vents continuously from the columns and reactors in the plant. Additionally, the incinerators receive waste gases from decontamination of vessels in VCM II unit, PVC unit and are capable of receiving waste gases from VCM 1 unit. Under normal conditions one incinerator is sufficient for the waste gas vents. The other incinerator remains in service but at a reduced temperature. The effluent from the incinerators is cooled in a waste heat boiler. HCl in the boiler effluent is recovered in absorber tower in the form of 10 % acid. Chlorine and any remaining HCl is removed from the vent stream in the caustic scrubber columns. Polyvinyl Chloride (PVC) Unit Process Description The PVC unit is designed to produce appro ximately 1,440 tons permitted of PVC per day, using suspension polymerization. The plant currently produces six grades of suspension PVC, with the ability to manufacture three grades at once. The PVC polymerization reactors consist of large jacketed vessels with agitators, reflux condensers and related equipment. The production of a single batch of PVC consists of mixing measured quantities of water (for ease of material transport and better product quality), suspending agents (to allow the water and PVC to form a uniform mixture), other chemical additives (for better product quality), and VCM (the raw material). After these ingredients are mixed, an initiator is added to start the polymerization reaction. The polymerization reaction is exothermic. The reaction process is cooled to maintain a desired process temperature. Once 80 to 90% of the VCM is reacted, the reaction is stopped through the addition of an inhibitor chemical. The unreacted VCM gas is removed from the reacti on vessel and then purified to be reused in future batches. The resulting mixture is a slurry of 30 to 35% by volume of PVC in water, which is pumped through filters to blowdown holding tanks. The PVC slurry is piped to the VCM Steam stripping column where as much unreacted VCM is removed as is possible. The stripping column operates under a slight vacuum for better separation. After stripping, the PVC slurry contains less than permitted 35 ppm VCM. The stripped VCM is vented to a gas holder to be purified for reuse. The PVC slurry is pumped through coolers to dryer feed the holding tanks. The PVC slurry is then pumped from the dryer to centrifuges where the slurry is separated into PVC wet cake and water. The water is pumped to the biological wastewater treatment plant for treatment. The PVC wet cake is fed into the dryers with a vibrating feeder. The dryer are either cyclone dryers or a fluidized bed dryer. PVC powder and air are separated by cyclone separators. The air ve nted from the tops of the cyclone dryers is passed through a water scrubber. The PVC powder is collected and sent to sieves, separating out the good product. The PVC product is then transferred by pneumatic air conveying system to silos for storage and loading operations. Each silo has vent that is controlled by bag filter air cleaning devices. The unreacted VCM which is recovered from the PVC reactors, blowdown tanks, and VCM steam stripping columns is compressed by liquid ring compressors. The compressed gas is piped to a triple set of condensers. The condensed crude VCM and water are separated in a decanter. The decanted water is piped to the PVC waste water stripping column area for purification. The condensible gases are vented to the VCM I or VCM II incinerators. The waste water system in the PVC unit consists of hard pipe to transport the VCM contaminated water, two storage tanks, and two waste water steam strippers. The water is pumped to the waste water storage, the n steam stripped of VCM, and sent to the Bio-plant to treat the unstrippable TOC. The control point is 0.2 ppm for VCM. The over head of the steam stripper goes through a condenser and the non-condensable gases go to the VCM I or VCM II incinerator. The VCM from the recovery condensers is returned to the wet VCM storage. |