Praxair - Geismar, LA - Executive Summary

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2218   LDEQ Facility ID Number 
 
The Praxair facility at Geismar, Louisiana is a chemical and industrial gas plant that produces, handles and/or stores the following substances that are regulated by the EPA's Risk Management Program rule, in excess of their threshold quantity: 
 
7 Methane; 
7 Hydrogen; 
7 Formaldehyde; and 
7 Ammonia. 
 
Methane, supplied by a local natural gas utility, is reacted in five different steam-methane reformer units to produce "syngas", which is a flammable gas mixture containing hydrogen, methane and other non-regulated substances.  The syngas that is produced by the five reformer units is further processed into several end-products at the facility, including pure hydrogen and methane.  The pure hydrogen product is delivered via pipeline to several nearby customers.  The pure methane product is liquefied and stored as a cryogenic liquid in an insulated vessel, and then distributed by truck to customers around the country.  Hydrogen and methane, as well as flammabl 
e mixtures, are listed as regulated flammable substances in EPA's Risk Management Program rule, each with a threshold quantity of 10,000 pounds.  The overall syngas production and storage process at the Geismar facility, including all production units and storage vessels, contains about 740,000 pounds of flammable gas and liquid, and is therefore subject to the RMP rule. 
 
Some of the syngas produced by the reformer units is also used indirectly as a raw material in a formaldehyde production process at the Geismar facility.  The formaldehyde gas is absorbed into a water solution, in either a 37% or 50% concentration.  These formaldehyde products are stored in our tank farm, and distributed to nearby customers via truck or pipeline.  Formaldehyde is listed as a regulated toxic substance in EPA's Risk Management Program rule, with a threshold quantity of 15,000 pounds.  The entire formaldehyde production and storage process at the Geismar facility contains over two million pounds of forma 
ldehyde solution, and is therefore subject to the RMP rule. 
 
The Geismar facility uses anhydrous ammonia to control the air emissions from one of the reformer units.  The ammonia is injected into the flue gas and passed over a catalyst to reduce potential air pollutants into harmless substances such as nitrogen and water vapor.  Anhydrous ammonia is listed as a regulated toxic substance in EPA's Risk Management Program rule, with a threshold quantity of 10,000 pounds.  The emission control unit at the Geismar plant contains up to 58,000 pounds of ammonia, and is therefore subject to the RMP rule. 
 
Under the RMP rule, Praxair is required to report one Worst Case Scenario that represents all regulated toxic substances on-site, and one Worst Case Scenario to represent all regulated flammable substances at the Geismar facility.  For toxic substances (ammonia and formaldehyde at Geismar), the Worst Case Scenario is defined by the EPA as the release of the entire contents of the largest vess 
el in the process, with essentially none of the safety systems and devices that are in place to prevent such an occurrence functioning as designed.  The release is assumed to occur over a 10 minute time period, and under the most stable atmospheric and weather conditions, which minimizes the dispersion and dilution of the release and presents the absolute worst case that could possibly occur.  Given all of these conditions, we are then required to estimate the distance to an EPA-specified toxic endpoint.  At the Geismar facility, the toxic Worst Case Scenario would involve the ammonia storage vessel, which contains about 58,000 pounds.  Using the criteria listed above, the Worst Case Scenario would result in a maximum downwind distance of about 2.8 miles to the EPA-specified endpoint.  To determine this distance, we used the EPA's "Risk Management Program Guidance for Ammonia Refrigeration." 
 
For regulated flammable substances, the Worst Case Scenario is defined by the EPA as the relea 
se of the entire contents of the largest vessel in the process, with essentially none of the safety systems and devices that are in place to prevent such an occurrence functioning as designed.  The released gas is assumed to ignite, causing a vapor cloud explosion.  Given these conditions, we are then required to estimate the distance to an EPA-specified flammable endpoint, which is defined to be an overpressurization effect of 1 pound per square inch.  At the Geismar facility, the largest vessel containing a regulated flammable substance holds about 38,000 pounds of methane.  Using the criteria listed above, the Worst Case Scenario would result in a maximum impact distance of about 0.28 miles to the EPA-specified endpoint.  To determine this distance, we used the EPA's "RMP*Comp" software. 
 
We are also required to report an Alternative Release Scenario, or planning scenario, for each toxic substance on-site and one Alternative Release Scenario to represent all flammable substances.  W 
hile an Alternative Release may never occur at a facility, it is generally accepted to be more likely, or more credible, than the Worst Case Scenario, and can be used by the facility and local response organizations to plan community emergency response activities.  The RMP rule assumes more typical atmospheric and weather conditions for an Alternative Release Scenario, and allows a facility to take credit for safety devices and other mitigation systems that are in place to minimize the likelihood and effects of a release.  When selecting an Alternative Release Scenario, EPA suggests a facility consider scenarios such as transfer hose releases, valve and flange leaks, pump seal leaks, and shipping container mishaps, among others. 
 
For the ammonia process at Geismar, any of the possible scenarios listed above would be equivalent to a release from a small hole (1/4" diameter) in a tank or pipe containing ammonia at the highest system pressure.  At the Geismar facility, a release of this t 
ype would result in a maximum downwind distance of about 0.1 miles, or 530 feet.  To determine this distance, we used the EPA's "Risk Management Program Guidance for Ammonia Refrigeration." 
 
For the formaldehyde process at Geismar, a credible Alternative Release Scenario would be a spill of 50% formaldehyde solution during truck loading.  While truck loading is always an attended operation, it is possible that a spill or overfill could occur due to equipment failure or human error.  Because of the administrative controls and safety devices that are designed into the truck filling system, a release of this nature would be quickly detected and stopped.  Assuming a one-minute release, at typical truck filling flowrates, it is estimated that about 1,000 pounds of 50% formaldehyde solution could be spilled.  Using the analysis criteria specified, an Alternative Release Scenario as described would result in a maximum impact distance of about 0.6 miles to the EPA-specified endpoint.  To deter 
mine this distance, we used the EPA's "Off-site Consequence Analysis Guidelines." 
 
For the flammable processes at the Geismar facility, a credible release would be the failure of a liquid line on the cryogenic liquid methane tank, with the released methane gas igniting and causing a small vapor cloud explosion.  A release of this type would result in a maximum impact distance of about 0.05 miles, or 264 feet.  To determine this distance, we used the EPA's "RMP*Comp" software. 
 
In accordance with OSHA's Process Safety Management standard and EPA's Risk Management Program rule, the Geismar facility has a comprehensive accident prevention program in place to ensure the safety of our employees, our neighbors and the community around us.  On a local level, this prevention program is built around process safety concepts such as: 
 
7 Documented process safety information to ensure the process design is understood and maintained throughout its life; 
7 Process hazard analysis to identify and con 
trol all of the hazards associated with handling toxic and flammable substances; 
7 Trained operators, using written operating procedures, to safely operate the process as intended; and 
7 Maintenance programs and procedures to ensure the on-going mechanical integrity of the process. 
 
The prevention program is audited periodically, by our corporate assessment group, to ensure that the process safety concepts and practices are in place and working effectively. 
 
As a result of our process safety and risk management practices, the Geismar facility has not had an accident involving any of the RMP regulated substances on-site in the last five years.  In the event of an emergency, the facility has an emergency action plan in place, which contains procedures for employees to follow, including notification of local response agencies.  All facility employees are trained in their role in the emergency action plan, and Praxair policy requires that emergency drills be conducted at least annually. 
 

raxair is committed to continuous improvement of its safety and environmental programs.    The Geismar facility participated in three internal safety-related audits in the last years, which are designed to evaluate and enhance the safety and environmental programs in place at a facility.  The facility has recently upgraded its hydrogen safety training program for employees, and continuously trains and drills its emergency response team members in all appropriate procedures and response methods.  Additionally, the facility has recently implemented an industrial hygiene and personnel monitoring program for employees who work around carbon monoxide.  These and other programs demonstrate Praxair's ongoing commitment to the safety and health of our facilities and communities. 
 
Praxair is a producer and distributor of industrial gases with almost 100 years of experience.  We are committed to being the best performing industrial gas company in all aspects of our business, including safety, he 
alth and environmental affairs.  Praxair is a member the Chemical Manufacturers Association's Responsible Care initiative, which is intended to ensure the safe operation of chemical facilities and enhance the relationships between the chemical industry and the communities in which we operate.  Internally, we use a combination of extensive engineering standards and design safety work processes, coupled with operational and personnel safety programs, to ensure the safe operation of all of our facilities.  Our company-wide goal of "Zero/Zero" (which means zero accidents and zero injuries or illnesses at every location) reflects the dedication and commitment to safety throughout the entire Praxair organization.
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