Celanese Bay City Plant - Executive Summary |
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EXECUTIVE SUMMARY FOR CELANESE BAY CITY PLANT FACILITIES ACCIDENTAL RELEASE PREVENTION AND EMERGENCY RESPONSE POLICIES At the Celanese Bay City Plant (BCP) employees are committed to designing, operating and maintaining all of our processes in a safe and environmentally sound manner. Accordingly, everyone is engaged in process safety activities. Employees work under a Total Safety concept that has integrated Process Safety, Health and Environmental along with Occupational Safety. This concept includes a behavior modifying accident prevention process. The following overview provides a description of the comprehensive risk management activities in place at our facility, including: 7 A description of our facility and use of substances regulated by EPA's RMP regulation 7 A brief description of the offsite release scenarios reported 7 An overview of our accidental release prevention programs 7 An overview of our emergency response program 7 An overview of planned improvements at the facility to help prevent accidental chemical releases from occurring. THE STATIONARY SOURCE AND THE REGULATED SUBSTANCES The BCP is situated in a rural area of Matagorda County several miles away from any residences. Our facility produces commodity organic chemicals using a variety of chemicals and processing operations. Some of these products include Vinyl Acetate, Butyl and Propyl Alcohol's, Heptanoic and Pelargonic Acid, n-Propyl Acetate, n-Butyl Acetate, and Isobutyl Acetate. In our processes, we use the following chemicals that the EPA has identified as having the potential to cause significant offsite consequences in the event of a substantial accidental release: Vinyl acetate monomer is our main product. It is produced in the Vinyl Acetate Process, and is used largely in the manufacturing of adhesives and paints. These materials are subsequently used for safety glass for automobiles, in floorings and rigid PVC pipe. About 4MMlbs are stored on site in nitrogen ine rted atmospheric storage tanks. Acetaldehyde is an impurity in the production of vinyl acetate. It is separated and sold in the merchant market. About 400,000 lbs. of acetaldehyde is stored on site as a liquid in pressurized spheres. The standard operating procedure limits the inventory in the spheres to 50%. Propylene is another substance covered by the RMP rule. It is a feedstock used in the Butanol process for the manufacture of butyl alcohol. Liquid propylene is supplied by pipeline. About 16,000lbs is contained in the piping within the plant fence boundary. KEY OFFSITE CONSEQUENCE ANALYSIS SCENARIOS EPA's RMP rule requires that we provide information about the worst-case release scenarios and alternative release scenarios for our facility. The following are brief summaries of these scenarios, including information about the key administrative controls and mitigation measures to limit the exposure distances for each scenario: Worst-Case Scenario - Regulated Toxic Ch emicals: The Worst Case Scenario (WCS) for a toxic involves a sudden rupture of the largest vinyl acetate storage tank which contains 4.1MMlbs. Using the EPA's OCA Guidance Reference tables and Equations, the vinyl acetate would produce a release which would reach offsite endpoints. The only mitigation that was allowed to be considered under the RMP rule was a dike system and emergency containment ditches that would contain the entire amount. Alternative Release Scenario - Regulated Toxic Chemicals: The Alternate Release Scenarios (ARS) for vinyl acetate is based on distillation tower upset condition that causes overpressure resulting in an elevated release when the pressure relief valve lifts discharging 12,000lbs of vinyl acetate vapor. The active process interlock system would minimize the release by alerting the operator and isolating the steam to the tower reboiler. The release of vinyl acetate would reach offsite endpoints with minor offsite impact. Worst-case Re lease Scenario - Regulated Flammable Chemicals: Acetaldehyde and propylene are the only covered flammable chemicals at our facility. Acetaldehyde was chosen over propylene for the Worst Case Scenario (WCS) based on the vapor cloud explosion potential. A WCS involving acetaldehyde would be a sudden rupture of one of the acetaldehyde spheres which contains 380,000 lbs. of the material. The maximum quantity stored in a sphere is limited to 50% by the standard operating procedure. The WCS would be a Vapor Cloud Explosion with offsite consequences having minor offsite impact. EPA's OCA Tables were used for these calculations. Alternate Release Scenario - Regulated Flammable Chemicals: The ARS would involve the rupture of a 2" line from the acetaldehyde storage vessel. It is assumed the leak would be detected and isolated within 60 minutes. The release is assumed to result in a vapor cloud explosion under neutral weather conditions with offsite consequences having very minor offsite impact. GENERAL ACCIDENTAL RELEASE PREVENTION PROGRAM AND THE CHEMICAL-SPECIFIC PREVENTION STEPS Our facility complies with the OSHA Process Safety Management Rule, and has taken all the necessary steps to comply with the accidental release prevention requirements set out under 40 CFR part 68 of the EPA. We take a proactive, comprehensive process safety management approach to prevent releases of hazardous chemicals. The following lists key management systems of our release prevention program: 7 Process Safety Information 7 Process Hazard Analysis 7 Operating Procedures 7 Training 7 Mechanical Integrity 7 Management of Change 7 Pre-startup Reviews 7 Compliance Audits 7 Incident Investigation 7 Employee Participation 7 Contractors The following chemical-specific prevention steps are taken to prevent accidental releases: Propylene chemical-specific prevention steps: 7 Propylene piping has remote isolation system Acetaldehyde chemical-specific prevention steps: 7 Use o f mounted water spray around the acetaldehyde spheres for fire protection 7 Sphere has remote isolation capabilities. Vinyl acetate chemical-specific prevention steps: 7 Use of nitrogen blanketing in storage tanks to avoid flammability 7 Use of PBQ additive to inhibit polymerization 7 Bulk storage is located away from processing areas in tank farm areas with secondary containment sufficient to handle spills. 7 Remote activated fire water monitors and emergency response equipment is readily available. The prevention steps and management systems listed above work together to prevent accidental chemical releases, and help protect both our employees and the communities in which we operate. FIVE-YEAR ACCIDENT HISTORY During the last five years, the BCP has not had any incidents with offsite impact from materials covered under EPA's RMP. There was only one incident that occurred in 1995 involving an injury associated with the Vinyl Acetate Process. An operator inhaled chemical vapors containing vinyl acetate that was released through a valve that was left open while pumping material. The operator required medical treatment and missed one day of work. EMERGENCY RESPONSE PLAN The BCP Emergency Plan provides procedures and guidelines for an orderly and safe response to emergency situations. Our program provides the essential planning and training for effectively protecting workers, the public, and the environment during emergency situations. The Emergency Plan includes response for protection of employees, the environment, community and equipment resulting from hazardous releases of chemicals, including vinyl acetate, acetaldehyde and propylene. The Emergency Plan provides instructions for notifying the Local Emergency Planning Commission (LEPC) immediately when appropriate. There are also emergency drills conducted by the BCP along with community first responders, sheriff's department and hospital. PLANNED CHANGES TO IMPROVE S AFETY The following is a list of improvements that are being implemented at the BCP to help prevent and better respond to accidental chemical releases: Conduct of Operations initiative is being implemented: 7 setting standards for handover of equipment between operations and maintenance, 7 following of Standard Operating Procedures, 7 re-certification of operators, 7 standards for equipment labeling, 7 approval and notification before removing or replacing safety equipment in service, and 7 verification of equipment readiness by operations prior to placing in service. A Community Alert network (CAN) computer phone system has been put in place that will notify residents by phones in the affected area about a release that could impact them, what happened and what to do. In summary, the BCP is committed to having an effective process safety management program. The BCP is also committed to having an open dialogue with the community to receive their concerns about existing plant activities and process safety issues through the Matagorda Community Advisory Panel and LEPC. The Risk Management Program at the Bay City Plant is aimed at protecting our employees and neighbors from a chemical release by seeing that the processes are designed, maintained and operated safely. ________ _ |