Patterson Frozen Foods, Inc. - Executive Summary |
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ACCIDENTAL RELEASE PREVENTION AND EMERGENCY RESPONSE POLICIES The Patterson Frozen Foods, Inc. facility has an emergency action plan in effect. The Emergency Action Plan (Plan) is detailed in the Emergency Planning and Response section of this PSM/RMP document. This Plan was designed to meet the following objectives: 1.) To save lives. 2.) To minimize and avoid injuries. 3.) To protect the environment. 4.) To minimize property damage. Patterson Frozen Foods, Inc. maintains a safety committee whose members are the designated emergency coordinators for the facility. The Plan provides the response organization and notification procedures, evacuation routes, ammonia health hazards, and mitigation procedures which will be implemented to respond effectively to emergency situations that may arise at the facility. This Plan is reviewed and updated at least once per year. This Plan was reviewed and updated to ensure compliance with the PSM and RMP regulations, as well as to incorporate facility changes. STATIONARY SOURCE AND REGULATED SUBSTANCE There are eight different processes that occur at Patterson Frozen Foods, Inc. The regulated substances of concern at Patterson Frozen Foods, Inc. are ammonia used in four interconnected refrigeration systems, and chlorine used at three treatment systems and one storage area. The processes that use or generate regulated substances include the following: Warehouse System, Warehouse #7 System, Main (engine room) System, East Complex System, Main Building Water Line Chlorine System, Main Building Chlorine Belt Spray System, East Complex Chlorine Dioxide System, and Chlorine Storage Area. Ammonia is use in one process as a refrigerant. The maximum intended inventory at Patterson Frozen Food, Inc. is 93,156 pounds. Chlorine is used at four separate processes to treat process water throughout the facility: - Main Building Water Line Chlorine System 2,000 lbs. (1 one ton container) - Main Building Chlo rine Belt Spray System 2,000 lbs. (1 one ton container) - East Complex Chlorine Dioxide System 300 lbs. (two 150 pound cylinders) - Chlorine Storage 4,600 lbs. (2 one ton containers and four 150 pound cylinders) The process are not co-located or interconnected, therefore, only the chlorine storage process is applicable to the regulation. The facility has implemented prevention programs that apply the same throughout. Warehouse System The Warehouse System provides refrigeration for cold storage rooms and various process equipment. High pressure warm liquid ammonia is fed through an intercooler serpentine coil to sub-cool the high pressure liquid ammonia. Sub-cooled liquid ammonia is then fed to various vessels and/or evaporators: Warehouse #5 liquid coolers, Warehouse #6 liquid coolers, Warehouse #6 accumulators, Warehouse #4 accumulator, cold storage rooms evaporators, 36: room evaporators, 36: room chiller, b ean cooler, repack cold room evaporators & repack plate freezers. The low pressure receiver or slop tank at Warehouse #4 is a vessel that acts as a protection for the booster compressors in the engine room. It "traps" excess liquid coming back from the evaporators through the suction line preventing any liquid from entering the booster compressors. When the ammonia level in the slop tank reaches the high limit float switch, the IT pump comes "on" and pumps liquid ammonia into the "dump system" or liquid transfer vessel that is located directly above the high pressure receiver. When the vessel is approximately 3/4 full the IT pump stops the three way valve to close the low side port & opens the hot gas port pressurizing the vessel until pressure equalizes with the pressure in the high pressure receiver then liquid ammonia drops (by gravity) into the high pressure receiver. In the refrigeration system the expansion device reduces the high pressure refrigerant to the accumulators and or evaporator's low pressure. The liquid cooler for Warehouse #5 cools the sub-cooled refrigerant to a lower temperature and then is fed to the Warehouse #5 coils. The liquid cooler at Warehouse #6 provides the same function as the cooler at Warehouse #5 but also feeds liquid to two (2) accumulators which supply "pumped" liquid to four (4) evaporator fan units. The low pressure vapor from all low side loads is then drawn back to the low pressure receiver. or slop tank by the booster compressors in the engine room. This vapor is compressed to a higher pressure and discharged by the boosters to the intercooler. Refrigerant vapor in the intercooler is drawn by the high stage screen compressors and compresses to a higher pressure and temperature so that the heat of vaporization and compression can be rejected and the vapor or gas can be condensed back into liquid by the condenser. As an option the warehouse engine room can also provide refrigeration to Warehouses #2 and #3 in the ma in building. Warehouse #7 System The Warehouse #7 system uses ammonia to provide refrigeration for cold storage rooms. High pressure liquid ammonia is transferred through an intercooler to lower the temperature of the high pressure liquid. High pressure liquid is also transferred from the receiver to evaporators 9 through 16. Subcooled liquid is transferred from the intercooler to the low pressure receiver, or accumulator, where the pressure (temperature) of the liquid is reduced. The resulting low pressure liquid is pumped to evaporators 1 through 8. The vapor return from these evaporators is cycled back to the accumulator. Booster compressors remove the refrigerant vapor from the accumulator and compress it to high pressure vapor. The compressed vapor from the booster compressors and vapor return from evaporators 9 through 16 are transferred to the intercooler, where refrigerant vapor is removed by the high stage compressors. Compressed vapor from the booster and high stage compressors is discharged through oil separator vessels to dissociate the oil build-up in the compressed vapor. High pressure vapor discharged from the high stage compressors is condensed by a condenser and transferred back to the receiver. Warehouse #7 is comprised of one cold storage room and a dock area which house evaporators 1 through 8 and 9 through 16, respectively. Unlike evaporators 1 through 8 which receive low pressure liquid from the accumulator, evaporators 9 through 16 receive high pressure liquid from the receiver, which enables products to be cooled at warmer temperatures. Main Engine Room System The Main (engine room) system uses ammonia in various process equipment and in Warehouses 1, 2, and 3. High pressure liquid ammonia is transferred through intercooler #2 to lower the temperature of the high pressure liquid. High pressure liquid is also transferred from the receiver to the low pressure receiver (slop tanks), and Model 32/Auto plate freezer accumulator. Subcooled liquid is transferred from the intercooler to Warehouses 2 and 3, Model 33 plate freezer accumulator, belt freezer accumulators, and chillers #1 through #4. The resulting low pressure liquid in the slop tanks is pumped to belt freezer #1, Warehouse 1 evaporators, and the roof main house dump system. Low side vapor return is cycled back to the low pressure receiver. With the exception of Warehouses 2 and 3, high side liquid/vapor return, namely Chillers #1 through #4, is transferred to the intercoolers. The coils in Warehouses 2 and 3 and evaporators in Warehouse 2 cycle liquid/vapor to the auxiliary warehouse slop tank. Booster compressors remove the refrigerant vapor from the low pressure receiver and auxiliary slop tank and compress it to high pressure vapor. The compressed vapor from the booster compressors is transferred to the intercoolers, where refrigerant vapor is removed by the high stage compressors. Compressed vapor from the booster and high stage compressor s is discharged through oil separator vessels to dissociate the oil build-up in the compressed vapor. High pressure vapor discharged from the high stage compressors is condensed by ten condensers and transferred back to the high pressure receiver. Warehouses 2 and 3 may receive subcooled liquid from the Warehouse system intercooler and cycle liquid/vapor return to the Warehouse system low pressure receiver. During loading of the Warehouse system, liquid is transferred from the Main (engine room) system. East Complex System The East Complex system uses ammonia to provide refrigeration for Belt Freezer #8. High pressure liquid ammonia is transferred through an intercooler to lower the temperature of the high pressure liquid. Subcooled liquid is transferred from the intercooler to the low pressure receiver where the pressure (temperature) of the liquid is reduced. The resulting low pressure liquid is pumped to Belt Freezer #8. The vapor return from Belt Freezer #8 is cycled back to the low pressure receiver. Booster compressors remove the refrigerant vapor from the low pressure receiver and compress it to high pressure vapor. The compressed vapor from the booster compressors and is transferred to the intercooler, where refrigerant vapor is removed by the high stage compressors. Compressed vapor from the high stage compressors is discharged through oil separator vessels to dissociate the oil build-up in the compressed vapor. High pressure vapor discharged from the high stage compressors is condensed by a condenser and transferred back to the high pressure receiver. The East Complex engine room adjoins the Warehouse engine room. The two engine rooms share a single building which is commonly referred to as the Warehouse engine room and/or "new" (East Complex) engine room. The East Complex system is a newly constructed system primarily designed to provide refrigeration for Belt Freezer #8. Main Building - Water Line Chlorine System The Main Building water line chlorine system at Patterson Frozen Foods uses chlorine for disinfection of water that is used for food processing at the facility. Chlorine gas leaving the one ton container passes through a vacuum regulator to the chlorinators. Still under vacuum from the chlorinators, it is drawn to injectors and mixed with water from the treatment process. The chlorine solution is distributed to several food processes. The water line chlorine system is operated under vacuum conditions. A single one ton container is used to provide chlorine gas to various treatment processes throughout the plant. Once the connected container becomes empty, it is replace by a full tank. This replacement is done by a Patterson Frozen Foods operator using a fork lift. While connected to the system, the one ton container is positioned so that the valves are vertically aligned. The vacuum regulator/heater assembly is placed on the top container valve to ensure that chlorine gas is pulled from the container . A vacuum is created when process water is pumped through the injectors. This flow generates approximately 1-3 in Hg vacuum which opens the vacuum regulator. After passing through the vacuum regulator, the chlorine gas is pulled to the chlorinator. The chlorinator is equipped with a rotameter. From the chlorinator, the gas is pulled through an injector where it is mixed with water and distributed to the treatment process. Main Building - Chlorine Belt Spray System The chlorine belt spray system at the Main Building at Patterson Frozen Foods is used to treat the process transfer belts or flumes. Unlike the water line chlorine system, the chlorine belt spray system uses two different treatment systems: 1) chlorination system with chlorine gas, or 2) chlorine dioxide system with sodium chlorite solution. Chlorine gas is transferred from the one ton container to chlorinator or rotameter through a vacuum regulator. The chlorination system directs the chlorine gas to the injector to add water to produce chlorine solution whereas the chlorine dioxide system mixes the chlorine with sodium chlorite solution before being introduced to the injector. The chlorine dioxide system will be utilized whenever the process transfer belts or flumes requires a higher efficiency. The Main Building chlorine belt spray system is operated under vacuum conditions for both chlorination and chlorine dioxide systems. A single one ton container is connected to the chlorine system to feed chlorine to the process treatment. When the on-line container becomes empty, it is replace with a full tank by a Patterson Frozen Foods operator using a fork lift. While attached to the system, the one ton container is positioned so that the container valves are aligned vertically. The vacuum regulator/heater assembly is placed on the top container valve to ensure that chlorine gas is pulled from the container. A vacuum is produced when process water flows through the injectors. A vacuum is prod uced when process water flows through the injectors. The flow of the water generates approximately 1-3 Hg in vacuum and opens the vacuum regulator. After passing through the vacuum regulator, the chlorine gas is sent to a chlorinator or a rotameter depending on which system is being utilized. For the chlorination system, chlorine gas leaving the one ton container passes through a vacuum regulator to the chlorinator. The chlorinator controls the flow of the chlorine gas to injectors where chlorine combines with water to produce chlorine solution. At the mixing point of chlorine and water, the solution becomes sufficiently diluted to no longer merit concern. For the chlorine dioxide system, the chlorine gas is transferred from the one ton container to the rotameter through a vacuum regulator. The rotameter then mixes the chlorine gas with the sodium chlorite solution before sending the mixture to the injectors. The injector combines the chlorine gas/sodium chlorite solution and w ater to make chlorine dioxide solution for the treatment process. East Complex - Chlorine Dioxide System The East Complex chlorine dioxide system at the Patterson Frozen Foods is used for the food processing water treatment. Chlorine gas from the 150 pound cylinders is pulled to chlorinators. The chlorine gas then is mixed with sodium chlorite solution before adding water at the injector. In the East Complex building there are two 150 pound cylinders connected to the chlorine dioxide system. All empty tanks connected to the chlorine dioxide systems are replaced with a full tank from the storage area. This replacement is done by the Patterson Frozen Foods operator using a hand truck. The chlorine dioxide system in East Complex is operated under vacuum conditions. There are typically two 150 pound cylinders on-line. The vacuum regulator/chlorinator assembly is placed on each container valve to draw chlorine gas from the container. A vacuum is produced from the water flows at the injectors. The flow of the water generates approximately 1-3" Hg in vacuum and opens the vacuum regulator/chlorinator assembly. The chlorine gas is combined with the sodium chlorite solution after passing through the vacuum regulator/chlorinator assembly. The mixture of chlorine gas and the sodium chlorite is then mixed with water to produce chlorine dioxide solution at the injectors for the treatment process. East Complex - Chlorine Storage Area The East Complex chlorine storage area maintains both full and empty chlorine tanks. A maximum of 3 one ton containers and six 150 pound cylinders can be stored at any one time, however, 2 one ton containers and four 150 pound cylinders are stored at any given time. HAZARD ASSESSMENT SUMMARY Worst Case Release Result Summary Scenario Description: Release of the maximum quantity of chlorine that can be stored in a vessel - 2,000 pounds in 10 minutes. The release rate of chlorine is calculated to be 200 pounds per minute. The most pessimistic meteorological conditions were used: 1.5 meters/second wind speed, and F stability. Exhibit 4-5 from the EPA's RMP Guidance for Wastewater Treatment Plants was used to determine the distance to the toxic endpoint of 3 ppm for rural topography. This release reaches off-site and may affect population receptors. No Environmental receptors were affected by the potential release scenario. Alternative Release Result Summary - Ammonia Scenario Description: A release of ammonia from resulting from a 1/4 inch diameter hole in a pipe. The release rate of ammonia due to the pressure of the tank is 134 pounds per minute. The meteorological conditions used were 3 meters per second wind speed, and D stability. Exhibit 4-4 from the EPA's RMP Guidance for Ammonia Refrigeration was used to determine the distance to the toxic endpoint of 3 ppm for rural topography. This release reaches off-site and may affect population receptors. No Environmental receptors were affected by the pot ential release scenario. Alternative Release Result Summary - Chlorine Scenario Description: A release of a chlorine mixture of gas and liquid from 5/16 inch diameter leak. The release rate of chlorine due to the pressure of the tank is 14.6 pounds per minute. The meteorological conditions used were 3 meters per second wind speed, and D stability. Exhibit 4-12 from the EPA's RMP Guidance for Wastewater Treatment Plants was used to determine the distance to the toxic endpoint of 3 ppm for rural topography. This release reaches off-site and may affect population receptors. No Environmental receptors were affected by the potential release scenario. ACCIDENTAL RELEASE PREVENTION PROGRAM AND CHEMICAL-SPECIFIC PREVENTION STEPS The Patterson Frozen Foods, Inc. facility including the ammonia refrigeration and chlorine treatment systems was designed and constructed in accordance with the Uniform Mechanical Code which specifically outlines requirements for the safe operation of ammonia refrigeration systems. These safety features include ammonia sensors and automatic shut down buttons both located throughout the facility. FIVE YEAR ACCIDENT HISTORY It was noted during the chlorine PHA study and ammonia PHA revalidation study that five accidental ammonia and chlorine releases have occurred at the facility within the past five years. 1) In December 1995, a thermal valve failed to release approximately 346 pounds of liquid ammonia in the closed warehouse #2. The local Fire Department responded and the leak was stopped by isolating the line. No injuries were reported. 2) In January 1996, a pressure relief valve failed and released approximately 166 pounds of vapor ammonia to off-site. Some fumes drifted down wind and was noticed about one block away. The local Fire Department responded, the facility was evacuated, and the leak was stopped by isolating the line. No injuries were reported. 3) In February 1996, over 100 pounds of saturated vapor ammonia were re lease in the main plant engine room. Nuts on a hydraulic pump were stripped down, creating a crack in the bottom of the pump. The local Fire Department was called to notify the nearby school. The facility was evacuated and the leak was stopped by isolating the line. One employee was sent to Del Puerto Hospital with an acute anxiety attack. She was treated and released back to work. 4) In June 1996, approximately 100 pounds of chlorine vapor/liquid mixture was released from a 150 pound cylinder. The fire department responded and isolated the immediate area. The responders stopped the leak by applying temporary "patch" and isolating that portion of the system. No injuries were reported. 5) In April 1999, a Patterson operator was raising a stack of plates in a package freezer and a hydraulic ram failed. The stack fell and broke an ammonia liquid line connection. Approximately 100 pounds of ammonia was released. The facility personnel was evacuated and the leak was stopped by isolating the line. No injuries were reported. The causes of the releases, the facility's subsequent actions, and the mitigation measures that resulted from these five incidents were discussed as part of the HAZOP study. EMERGENCY RESPONSE PROGRAM The Patterson Frozen Foods, Inc. has an emergency action plan in effect at the facility. The Emergency Action Plan (Plan) is detailed in the Emergency Planning and Response section of this PSM/RMP document. This Plan was designed to meet the following objectives: 1.) To save lives. 2.) To minimize and avoid injuries. 3.) To protect the environment. 4.) To minimize property damage. Patterson Frozen Foods, Inc. maintains a safety committee whose members are the designated emergency coordinators for the facility. The Plan provides the response organization and notification procedures, evacuation routes, ammonia health hazards, and mitigation procedures which will be implemented to respond effectively to emergency situation s that may arise at the facility. This Plan is reviewed and updated at least once per year. This Plan was reviewed and updated to ensure compliance with the PSM and RMP regulations, as well as to incorporate facility changes due to the renovation of the facility. PLANNED CHANGES TO IMPROVE SAFETY The Process Hazard Analysis study conducted on May 3, 1999 provided mitigation measures to improve safety at the Patterson Frozen Foods, Inc. facility located at 100 West Las Palmas Avenue in Patterson, California. All recommendations are scheduled to be complete by May 2000. Ammonia Refrigeration Systems REV01 Check the pH of the diffusion tank water at least once every six months. REV02 Ensure that all employees are trained in emergency response plan (i.e, awareness of ammonia and chlorine, procedures for reporting a chemical release, and evacuation procedures) REV03 Consider shutdown the system in the engine room when the solenoid shut off (high level alarm) or when the ammonia lev el reaches 4%. REV04 Check the number of SCBAs (at least four) in the facility to respond during an IDLH situation. REV05 Test the ammonia detectors at least once every six months. REV06 Test the high level shutdown (cutouts on compressors and vessels) at least once a year. REV07 Consider installing concrete poles outside the main engine room to protect the high pressure receiver from outside impact. Chlorine Treatment Systems R01 Establish an inspection/maintenance procedures for the vacuum regulator at the cylinder valve. R02 Check the manufacturer's recommendation on changing the filter and include in the existing preventive maintenance. R03 Check the number of SCBAs (at least four) in the facility to respond during an IDLH situation. R04 Consider installing a chlorine sensor and alarm system in the east side processing building in case of a chlorine leak. R05 Post chlorine sign near the chlorination/chlorine dioxide system. R06 Consider documenting the equipment chang e on the log manual. R07 Remove combustible materials away from the chlorine storage area to protect against potential for fire. |