Trigas, Inc. (Pasadena) - Executive Summary

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In this industrial gas air seperation plant, (TRIGAS Pasadena), we handle anhydrous ammonia which is considered hazardous by EPA, OSHA, etc.  The same properties that makes anhydrous ammonia valuable as a source gas for the production of Hydrogen & Nitrogen, also makes it necessary to observe certain precautions in handling anhydrous ammonia.  Overall, the prevention of unnecessary human exposures, reducing the threat to our own personal helath as well as our co-workers, and reducing the threat to nearby members of the community is the main goal of oncorporating this Risk Management Plan into our daily operations.  It is our policy to adhere to all applicable federal and state rules and regulations.  Safety depends upon the manner in which we handle and use anhydrous ammonia combined in coordination with the operations and maintenance procedures provided by the manufacturer of the ammonia dissociator, as well as the training of our personnel. 
The primary purpose of this facility is to 
manufactuer industrial gases (liquid oxyggen, liquid nitrogen & liquid argon).   The dissociator is designed to economically produce a 75% hydrogen, 25% nitrogen atmposphere.  The nitrogen is vented to the atmosphere, the hydrogen is used to remove oxygen from a crude argon stream.  Anhydrous ammonia is received by truck shipments, and stored in one aboveground storage vessel.  The storage vessel is directly linked to the ammonia dissociator by valves, fittings, and piping.  Anhydrous ammonia is liquified under pressure in the storage vessel, but ammonia gas is released into the dissociator for the production of nitrogen and hydrogen.  The maximum amount of anhydrous ammonia stored at any given time is 48,000 pounds. 
Our employees conduct proper start-up procedures as listed in the manufacturer's O&M Manual for the ammonia dissociator (ROLOCK).  They also review the operating procedures and maintenance tasks when needed to insure the proper and safe use of the ammonia dissociator to  
prevent a release of ammonai vapor.  The maintenance tasks are completed as needed, with the most critical being visual inspections of valves, fittings, pipe joints, etc. for deterioration.  Also, keeping the system clean and free of oil is an important aspect of the maintenance tasks performed according the manufacturer's recommenndations.  Mechanical integrity of the system is completed by keeping a listing of parts recommended by the manufacturer for change-out if and when needed.  Mr. Ray Roberts (Plant Manager) will ensure that the installation/repair of the dissociator system is completed properly.  This facility has a Process Safety Management  plan which they are incorporating into their daily routine to comply with the Level 3 Prevention Program Requirements.  They also have a Lock-out/Tag-out program, Hazard Communication Program, Confined Space Program (if needed), and an Emergency Action Plan to aid in the prevention of accidental releases of anhydrous ammonia.  These progr 
am, along with the Process Safety Management Program comprise a huge portion of TRIGAS's prevention portion. 
The emergrncy response (action) program was developed with the assistance of Environmental Data Services, Inc., the LaPorte LEPC, and the Pasadena Fire Dept.  If an anhyrdous ammonia release occurs at the 13440 Bay Area Blvd. location, the manual alarm will be activated (in main office) to inform employees of a release.  Plant Manager (Ray Roberts) will get personnel organized for an emergency action and possible evacuation.  The emergency action plan consists of on-duty operators shutting off the ammonia dissociator by pressing the on/off button.  If this doesn't stop the release, then the ammonia vessel vapor valve can be turned off to prevent the further release of ammonia vapor from the vessel.  If these actions do not stop the release of ammonia, evacuation procedures will begin.  A head count will be made of employees according to shift rosters, and Tom Larson (VP Product 
ion/Safety) will be notified.  The 911 call will also be made to notify the Pasadena Fire Department, the Laporte LEPC, and the Pasadena Police Dept. of the release.  The LaPorte LEPC will organize the Emergency Response Activities, and will help the Pasadena Fire Dept. mitigation the vapor release by water spray, or if mitigation doesn't work, evacuation of the affected population.   
The worst case scenario for this facility is the failure of the storage vessel for anhydrous ammonia. This would be a release of 48,000 pounds of ammonia vapor into the atmosphere.  Active mitigation has been considered for this scenario, consisting of manual shut-offs, of the vapor feed from the storage vessel to the dissociator, and the manual shut-down of the controls for the dissociator.  Passive mitigation was not considered for this scenario.  It is assumed that the entire contents of the cylinder are released as vapor.  The distance to endpoint of 0.14 mg/l for the worst case scenario is 3.4 miles 
.  The area surrounding the facility is flat, yet the trees, vegetation and other structures around the facility makes the determination that this area is urban.  The worst case scenario would impact approximately 130,000 persons using the Landview Software.  This number may be exagerrated somewhat, however, with the numbers of heavily employed industrial manufacturers in the area, the affected population may not be households, rather employees. 
An alternate release scenario was determined for this facility.  The ammonia dissociator operates on low pressure, and high temperaturs.  Pressure regulators reduce the pressure to no more than 25 psi, and no less than 15 psi.  The most likely release would be a vapor line failure which would result in an estimated release of 50 pounds of ammonia vapor in 10 minutes (5 pounds per minute).  The release of 50 pounds of ammonia vapor would result in a distance to endpoint of approximately 0.06 miles.  This relatively short distance would impact a 
pproximately 140 persons using the Landview Software. 
There have been no accidental releases of anhydrous ammonia from this facility in the past five years.  The operators at this facility conduct proper oprating and maintenance procedures to aid in the prevention of accidental releases of ammonia.  TRIGAS (Pasadena) has started the incorporation of Process Safety Management for their Level 3 Prevention Program to further emphasize their efforts in preventing accidental releases of anhydrous ammonia.
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