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HomeMy WebLinkAboutRISK MANAGEMENT NESTLI~ ICE CREAM COMPANY BAICERSFIELD, CALIFORNIA RISK MANAGEMENT AND PREVENTION PROGRAM AUGUST 1995 RISK MANAGEMENT and PREVENTION PROGRAM Addendum RECEIVED /~U~ 2. t3 1995. HAZ. MAT, DIV. Prepared For: NESTLl~ ICE CREAM COMPANY BAKERSFIELD, CALIFORNIA Revised and Updated August 1995 Prepared By: ~ QUAD ENGINEERING, INC. 5500 Ming Avenue, Suite 410 Bakersfield, California 93309 805/835-8300 TABLE OF CONTENTS 1.0 2.0 3.0 4.0 5.0 6.0 Purpose ................................................. 1 Ammonia Refrigeration Process Equipment ........................... 2 Accident History ............................................ 4 Offsite Consequences Analysis ................................... 7 Recommended Additional Steps .................................. 8 Status of 1994 RMPP Implementation .............................. 9 Appendix A Appendix B ! I I I I I I i I I I I I I I I 1.0 INTRODUCTION 1.01 Purpose The purpose of this addendum is to revise and update the Nestl6 Ice Cream Company (Nestl6), Bakersfield, California Risk Management Prevention Program (RMPP) dated April 1994. A revised RMPP is required whenever a modification is made to the facility which would materially affect the handling of an acutely hazardous material. Nestl6 uses anhydrous ammonia in a closed cycle refrigeration system for the manufacture of ice cream and frozen novelties. Anhydrous ammonia is classified as an acutely hazardous material (AHM). This addendum is intended to be a supplement to the RMPP dated April 1994. Please refer to the April 1994 RMPP for complete details. Changes and facility modifications made and not previously addressed in the RMPP include the following: The total quantity of anhydrous ammonia is now estimated to be approximately 100,000 pounds. The 1994 RMPP update identified a total of 82,500 pounds. The original RMPP dated 1989 identified a total of 120,000 pounds of anhydrous ammonia. 2. Nestl6 has added the following process equipment to the main production floor: 2 Drum Stick freezer tunnels 1 Frigo-Scandia freezer tunnel with backup ammonia pump 8 ice cream freezers Nestl6 has added 3 new 8,000 gallon refrigerated mix tanks (MT 30, 31, 32) for storage of ice cream mix prior to freezing. The mix tanks are located outside the building in an enclosed space. In addition to the above changes, Nestl6 has recently reported two accidents which involved the release of anhydrous ammonia. This addendum will address those accidents, their underlying cause and measures to avoid recurrence of the accidents. Finally, the revised RMPP will address any changes required on the offsite consequences analysis as a result of changes made in the process equipment. Section 6.0 indicated the status of the 1994 RMPP Implementation. - Nestl6 1 ~ I I 2.0 AMMONIA REFRIGERATION PROCESS EQUIPMENT 2.01 Ammonia Inventory The best estimate of the total quantity of anhydrous ammonia contained within the closed loop vapor compression refrigeration system is approximately 100,000 pounds. This amount is based on a June 23, 1995 audit which indicated a total inventory of 99,811 pounds. New process equipment recently added required the addition of 4,125 pounds (750 gallons) of ammonia refrigerant. Additional ammonia was added to the system to bring up the level in receivers to optimize performance during startup. 2.02 Process Equipment Changes Nestl6 has added the following process equipment to the main production floor: Drum Stick Freezer (2) Suction Connection Liquid Connection Hot Gas Connection Location 6" (-55*) 1-1/4" Liquid 1-1/4" Hot Gas Main Production Floor Frigo Scandia Freezer Suction Connection Liquid Connection Hot Gas Connection Location 4" (-55*) 1-1/4" Liquid Ammonia 1-1/2" Hot Gas Main Production Floor Ice (2regm Freezers (8 total) Suction Connection: Liquid Connection Hot Gas Connection Defrost Relief Pressure relief Location 2" ¢38°) 3/4" HP Liquid Ammonia 1" Hot Gas 3/4" to main header Main Production Floor Schematic drawings for the new process equipment are included in Appendix A. 2.03 Mix Tanks Nestl6 has added 3 new mix tanks (MT 30, 31 and 32), each with 8,000 gallon capacity. The mix tanks hold ice cream mix prior to freezing. The tanks are ammonia refrigerant cooled via direct _ Nestl6 2 ~ I I I I I I I I i I I i I I I I I I expansion. A Mueller Temp-Plate Cooling Wall with a volume capacity of 0.22 cu. ft. is used for heat transfer. The mix tanks are similar to mix tanks used for storage of milk in the receiving area and for ice cream mix inside the building. The tanks are located outside the main building, in line with the interior mix tanks. The tanks are protected by a concrete wall. The mix tank specifications are: Tag No. Suction Connection: Liquid Connection Hot Gas Connection Pressure relief .Location Temp Plate Oper. Pres. MT30, MT31, MT32 1-1/4" (20 °) 1/2" HP Liquid Ammonia None 1-1/4" to 6" main header Building exterior 33-35 psig (150 psig max.) A schematic drawing and Standard Operating Procedure (SOP) for the mix tanks are included in Appendix B. Nestl~ 3 ~ '1 I I 1 I I I 1 I I I I I I 3.0 ACCIDENT HISTORY 3.01 Description of AHM Accidents Nestl6 has had two reportable AHM accidents since the last RMPP revision. March 18. 1995.8:45 p.m. A Utilities Technician performing routine maintenance on Chiller No. 4 discharged approximately 11 pounds of ammonia into a bucket while attempting to drain oil from the chiller. The technician was wearing shoulder length neoprene gloves and a full face cartridge respirator. While draining the oil, something momentarily stuck in the valve and then suddenly blew out discharging oil and ammonia. After discharging the ammonia, the technician left the engine room, removed the gloves and waited until breathing was easier. The technician attempted to re-enter the room to shut off the valve. The ammonia monitor indicated 85 ppm so the technician left the engine room and hit the "all call" to evacuate the plant. Two technicians then donned SCBA and re-entered the engine room to re-check to ensure the valve was closed. The ammonia dissipated within the room and the residual was removed with large quantities of waster. The Bakersfield City Hazmat Team responded to the spill. Re-entry to the plant occurred following clearance by the Hazmat Team. One OSHA reportable injury occurred. The utility technician received burns on this arms as a result of ammonia spilling. Underlying Cause of the Accident: The accident occurred while a technician was performing the routine maintenance of draining oil from the chiller accumulator. The accumulator is a pressure tank containing liquid ammonia at -38'F in the bottom of the tank and gaseous ammonia at the top of the tank. Oil from the ammonia compressors gradually accumulates at the bottom of the tank and requires periodic removal. The accident is believed to have been caused by either hardened or very viscous oil and/or debris lodging in the accumulator drain valve. The oil becomes very hard at the cold temperatures (-38*) inside the accumulator. The blockage in the valve was suddenly dislodged when the valve was further opened resulting in oil and ammonia blowing out. Normally, a blockage does not occur and technicians are able to bleed off the oil in a controlled flow, thus minimizing the discharge of ammonia. One technician was working alone, draining the oil. When the sudden discharge occurred, he was splashed with oil and ammonia on his protective clothing. His mask became saturated and he could not breathe. He therefore left to obtain a new mask and gloves, leaving the valve unattended until he could return. Nestl~ 4 ~ Measures to avoid recurrence of accident: Nestl6 has implemented the following procedures to avoid the recurrence of the accident: 1. Utility technicians will work in pairs when draining oil from accumulators. Nestl~ will provide additional training to technicians on the hazards of draining oil from accumulators. o Refrigeration technicians will be trained to use extreme caution when opening valves to drain oil. In addition to the above, Nestl6 is evaluating the cost-effectiveness of installing a hard piped oil drain system. In this system, oil will be drained and isolated from the accumulators to a pressure vessel. The pressure vessel is then heated with ammonia hot gas through a heat exchanger. The liquid ammonia in the vessel would be driven off as a gas to the ammonia system suction piping. The heated oil can then be drained from the vessel to a waste oil container without danger of ammonia discharge. March 24. 1995.9:15 a.m. A contractor, Valley Sun Mechanical, was installing piping for the new mix tanks (MT 30, 31, and 32). As a large pipe, approximately 14 feet long, was lowered through the roof over MT01, it slipped out of its rigging. The pipe dropped into the enclosure striking and bending the ammonia suction line near the top of the tank and the flange on the suction line. The break in the line resulted in a release of approximately 80 pounds of ammonia. The tanks were immediately isolated and the exhaust system activated to begin ventilation of the room. The EPA and National Response Center were notified as a precaution. No injuries occurred as a result of this release. Underlying Cause of the Accident: The accident occurred as a result of careless construction practices of a contractor working for Nestl6. The pipe being lowered through the roof was not adequately and safely rigged, thus allowing the pipe to slip and fall. Measures to avoid recurrence of the accident: Nestl6 has implemented the following procedures to avoid recurrence of the accident: Contractors working for Nestl6 in and around ammonia piping systems will be provided instructions in the hazards of ammonia and the potential impact on an ammonia related accident on Nestl6's operation. Contractors will be warned to use extreme caution around ammonia systems. Nestl~ 5 ~ I I I I I I I I I I I I I I Nestl6 personnel will closely supervise and inspect all contractors working in and around the ammonia systems. ' When contractors are working on or around ammonia systems, they will be required to submit proposed safety procedures for approval by Nestl6. When pipe is to be rigged and lowered, the contractors will be instructed to weld clips to the pipe to ensure that the rigging will not slip. Nestl~ 6 ~ 4.0 OFFSITE CONSEQUENCES ANALYSIS 4.01 Release Scenarios The new equipment and larger ammonia inventory was determined to have no impact on the offsite consequences analysis previously prepared. The worst case release scenarios do not change with the new equipment. Possible releases from the new equipment have already been evaluated in release scenarios 1, 2 and 5. Nestle 7 ~ 5.0 RECOMMENDED ADDITIONAL STEPS The following items are recommended to be completed to reduce the risk of an accident associated with the new facility modifications. These are in addition to the risk prevention programs already in place and recommended in the April 1994 RMPP update. Install ammonia detector in the enclosure for new 8,000 gallon mix tanks (MT 30,31,32). The ammonia detector should be integrated into the existing plant alarm system. This ammonia detector has been installed. Immediately implement the procedures described in Section 3.01 anytime oil is to be drained from an accumulator, receiver or other ammonia pressure vessel. These procedures are necessary to reduce the risk of an accident similar to that described in Section 3.01. Review and evaluate the cost-effectiveness of a hard piped system, as described in Section 3.01, for draining oil from receivers, accumulators and other ammonia pressure vessels. If the system is cost-effective, implement the system first on those vessels which require frequent oil draining and which have the greatest potential for an accident. Second, implement the system on the remainder of the pressure vessels where it is cost-effective. Immediately implement the procedures described in Section 3.01 any time a contractor is working for Nestl6 in and around the ammonia refrigeration system. Nestl~ 8 ~ I I I I I I I I I I I I I I I t I I 6.0 STATUS OF 1994 RMPP IMPLEMENTATION The current status of the 1994 RMPP implementation is as described below: Install ammonia detector in guard shack. The ammonia monitoring system alarms have been installed. Review ammonia piping runs and install shields and guards where impacts are likely. The review has been completed. Nestl6 will evaluate and prioritize the list by October 1, 1995 for implementation. 3. Complete ammonia safety audit. The audit was completed and current as of April 1994. Develop comprehensive ammonia refrigeration process flow diagrams. A refrigeration flow diagram, for the engine room was completed and included as a part of the 1994 RMPP update. Additional flow schematics are now complete and will be posted at key locations. o Develop a written ammonia safety awareness program. The plants Hazardous Communication Program provides training in ammonia safety. Develop a written ammonia emergency plan. The plan is complete. Site plans are being developed for posting. o Fully implement the preventative maintenance program. The preventative maintenance program has been implemented using the plant's ELKE system. This computerized program automatically writes works orders for preventative maintenance items. Develop a response plan for an ammonia emergency that will result in downwind exposure. The response plan has been developed in cooperation with the Bakersfield Fire Department. The Fire Department has conducted on-site ammonia safety meetings and has toured the facility. No table top exercise or simulated drills have been conducted. Develop a written training program for refrigeration technicians for ammonia safety. Ammonia safety training has been included in safety training for the last three years. Nestl6 uses a contractor, Westech, for training. 10. Develop written work procedures for operation and repairs on the refrigeration system. Nestl6 is in the process of developing standard operating procedures (SOPs). SOPs have been written for the new mix tanks (MT 30,31, 32) and are included in this RMPP update. Nestl6 is currently reviewing SOP procedures for other similar plants and will utilize those procedures to facilitate the writing of SOPs for the Bakersfield plant. Procedures for operations and repairs are currently based on the knowledge, experience and training of the refrigeration technicians. Nestl6's goal is to have written SOPs by January 1, 1996. Nestl6 9 ~ 11. Construct a 2 foot high containment wall surrounding the pump down receiver. containment wall was completed in April of 1994. The Nestl6 10 ~ '1 i i I I I [I I I I I I I i Appendix A ILl LINE 12 TUNNEL REFRIGERATION LINE 16 TUNNEL REFRIGERATION LINE ~ TUNNEL REFRIGERATION Appendix B Page I of 7 STANDARD OPERATING PROCEDURE MIX TANll:~ 30, al, 82 Objective: This procedure is established t~ describe the Technical Operating Specifications (TOS) and to set forth Standard Operating Procedures (SOP) for the operalion of the arnmoni~ cooling on Mix Tanks 30, 31, 32. The purpose of the TOS is to provide a description of the tanks defining their function, operating conditions and limits, consequences of deviations from operating limits, description of controls, instrumentation and safety systems and setting the operating conditions. The purpose of the SOP is to set forth the proper steps for starting, monitoring normal operation, stopping and re-starting the ammonia cooling on the tanks. Careful attention to valve positions is important to this procedure as it is the ammonia cooling that maintains mix temperature withi~ legal'limits. Among the incidents we are trying to prevent are: Injury to facilities technics. Warm Mix Over pressurization of the tanks resulting in operation of pressure ~,elief valves or failure or rupture of components and consequent release of ammonia_ to atmosphere. Dep artment:Facilities Operator: Equipment: Related Documents: Facilities T~hniclan Mix Tanks 30, 31, 32 Paul Mueller Company Drawing # FP08129 Nestle Drawing # P&ID-MT30-32 '4/8/95 Page 2 of 7 STANDARD OPERATING PROCEDURE MIX TANKS 30, 31, 3g TECHNICAL OPERATING SPECIFICATION (TOS) Function: Provide ammonia cooling via direct exp~n~on to mointain mix temperature in 80~ gallon tank. DESCRIPTION CAPACITY/SIZI~ OPERATING LIMITS DEVIATIONS/CONSEQUENCES MU~.I ,L~,R TEMP-PLATE COOLING WA~,~, VOLUME; .22 CU.FT Pressure: 33-35 psig 150 psig maximum pressure Over pressurization may result in operation of pressure relief valves DESCRIPTION ITEM NUMBER FUNCTION POSITION/SETPOINT Col~tro!s and instrumentation Level Sensor Level Sensor Level Sensor LS-32 Measure mix level in MT-30 and turn on REF-30 Measure mix level in MT-31 and turn on REF-31 Measure ,nix level in MT-32 and turn on REF-32 ON above 200 gallons Offbelow 200 gallons ON above 200 gallons Off below 200 gallons ON above 200 gallons Off below 200 gallons ~8~5 Page 3 of 7 STANDARD OPERATING PROCEDURE MIX TANKS 30, 31, 32: DESCRIPTION ITEM NUMBER FUNCTION POS1TION/SETPOINT Controls and instrumentation (cont'd) IAcluid supply solenoid valve REF-30 Liquid supply solenoid valve REF-31 Liquid supply solenoid valve REF-32 Thermal expansion valve TEV-30 Thermal exp~n~on valve TEV-31 Open and close in response to LS-30 Open and close in response to LS-31 Open and close in response to LS-32 Provides variable orifice for ammonia expansion into Mueller Temp-Plate C~liog Wall. on MT-30 Provides variable orifice for ammonia expnn~on into Mueller Temp-PLate Cooling Wall. on MT-31 Open above 200 gallons of mix in vessel Close below 200 gallons of mix in vessel Open above 200 gallons of mix in vessel Close below 200 gallons of mix in vessel Open above 200 gallons of mix in vessel Close below 200 gallons of mix in vessel Automatic valve set to 8° to 12° superheat Automatic valve set to 8° to 12° superheat 4/8/95 Pag~ 4 ~f 7 STANDARD OPERATING PROCEDURE MIX TANKS 30, 31, 3Z DESCRIPTION ITEM NUMBER FUNCTION POSITION/SETPOINT Controlz p~nd instrlunentatlola (cont'd) Themal expansion valve TEV-32 Provides variable orifice for ammonia expansion into Mueiler Te_m_p-Plate Cooling Wall. on MT-32 Automatic valve set to 8° to 12° superheat Safety systems Relief valve Relief valve Relief valve RV-30 RV-31 RV-32 Open on rise in Mueller Temp-Plate Cooling Wall on MT-30 and relieve to Common relief header Open on rise ~n Mueller Temp-Plate Cooling Wall on MT-al and relieve to Common relief header Open on rise in Mueller Temp-Plate Cooling Wall on MT-32 and relieve to Common re]id header 150 paig 150 psig 150 psig 4/~/95 Page 5 of 7 STANDARD OPERATING PROCEDURE MIXTANKS 30, 31, 32 STANDARD OPERATING PROCEDURE (SOP) TASK FLOW DIAGRAM 1. ,.get up tanks for initial oper ,ation ! ...... 2. open Valves 3. Monitor normal operation ,, 4. Close valves i 5. Restart tanks after ahutdown I ~8/95 Page 6 of 7 STANDARD OPERATING PROCEDURE MIXTANKS 30, 31, 32 TASK STEP COMMENT THE FOLLOWING STEPS ARE FOR MT-BO. THE PROCEDURE FOR MT 31 AND 32 IS THE SAME USING THE APPROPRIATE VALVES FOR MT 31 AND 32. REFER TO P&ID-MT~O-B2. 1. Set up t~n]~ for fnjtial oPeration 1. Close V30-1, V30-2, V30-3, V30-4 TEV30 2. Open TEV30 two full turns 2. Open Valves 1. Slowly open V30-1 one turn. When flow noises stop fully open V30-1. Fully open V30-3 Fully open V30-2 Allows pressure to equalize with compressor suction. Allows liquid to flow through TEV30 when REF-30 opens. Monitor normal operation 1. Monitor REF-30 to ensure the valve opens and doses at the correct setpoints. Page 7 of 7 STANDARD OPERATING PROCEDURE MIX TANKS 30, 31, a2 TASK STEP COMMENT 3. Monitor normal operation (cont'd) 2. Adjust TEV30 as necessary to maintain Mix temperature. <45 degF 4. Close Valves 1. Close V30-2, V30-3 2. Leave V30-1 open to allow for a constant equalization afpressure within the Temp-Plate Cooling Wall. Stops liquid flow V30-1 is to be abut only to isolate the tank for maintenance. 6' COMMON HEADER - VENT UNE TIEIN TO EXISTING AMMONIA LINES I ,N EA~ ~,x 'r,,,.~< ~ T30 MT51' · ~ 3/~" HPL V-2 ~/~R~-30 ~/~REF-3' ~/E-REF-32 ) .SOL ~_~ .~o ~o_.~_~o ~L._. V31-2 V32-2 LEGEND: V - STOP VALVE TEN/ - THERMAL EXP, VALVE S( H~ R\ )L - SOLENOID VALVE )L - HIGH PRESSURE LIQUID - RELIEF VALVE ~llNeI~ Ice Crea~n Coznp~n7 I I I I I I