Air Products, Hennepin, IL - Executive Summary

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Executive Summary 
 
 
Air Products and Chemicals, Inc. 
Hennepin, Illinois Facility 
 
 
1.  Accidental release prevention and emergency response policies: 
 
At this facility, we manufacture annealing gas used in steel making.  The annealing gas manufacturing process uses  ammonia.  Ammonia, in the amounts handled by our facility, exceeds the threshold quantities set by EPA.  It is our policy to adhere to all applicable Federal and state rules and regulations.  Air Products manages the safety of the regulated processes by means of operating procedures, equipment testing and inspections, safety devices (e.g., alarms, shutdowns, instrumentation, relief devices) inherent in the design of this facility and other controls and systems designed to prevent accidental release of hazardous chemicals.  Safe work practices and training of our personnel supplement the inherent safe design of the plant. 
 
Our emergency response program is based upon OSHAs HAZWOPER regulation.  The emergency response plan i 
ncludes procedures for the notification of the local fire authority and Hazardous Materials unit so that appropriate measures can be taken by local responders to control accidental releases. 
 
This document has been prepared in accordance with the EPAs Risk Management Plan regulation (40 CFR, Part 68).  The substances and processes considered during the preparation of this RMP and the scenarios described were selected based on criteria established in the regulation. 
 
2.  The stationary source and regulated substances handled: 
 
One of the main products of this facility is a gaseous mixture of hydrogen and nitrogen in a 3:1 ratio.  This "annealing gas" is used by our customer in their steel manufacturing process.  In the annealing gas production process, liquid anhydrous ammonia is vaporized and "dissociated" or split into its constituent three parts hydrogen and one part nitrogen in a heated catalytic reactor.  The annealing gas is delivered via pipeline to the nearby steel mill.   
 
Liq 
uid anhydrous ammonia is stored onsite in a single tank.  The tank has a maximum capacity of 21,000 gallons but is never filled with more than 18,000 gallons of liquid, so as to maintain an adequate vapor space. The liquid ammonia is delivered to the site by tank truck.  The liquid ammonia is vaporized by electric vaporizers and the gaseous ammonia is piped to the dissociation reactors. 
 
The regulated process at this facility is the ammonia storage and dissociation system.  Ammonia is the only  regulated substance handled at this facility in an amount exceeding a threshold quantity.  The maximum amount of ammonia at this facility is 95,000 pounds. 
 
 
3.  The worst-case release scenario(s) and the alternative release scenario(s), including administrative controls and mitigation measures to limit the distance for each reported scenario: 
 
The "worst-case scenario" (WCS), as defined by the EPA, is a catastrophic failure of the anhydrous ammonia storage tank releasing all 18,000 gallons plus 
the gas in the vapor space (94,300 pounds total) over a ten minute period. The maximum distance to the EPA-defined endpoint (0.14 mg/L or 200 ppm) for this WCS reaches receptors offsite.  Although we have active controls directed at preventing such releases, no credit for active or passive mitigation measures were taken into account in evaluating this WCS. 
 
The "alternative case scenario" (ACS) is a break in, or sudden uncoupling of, the transfer hose from an ammonia tank truck while filling the storage tank.  Liquid ammonia is assumed to flow from the hose at a rate of 1100 lbs/min.  The ammonia vaporizes to form a cloud which reaches receptors offsite.  The EPA-defined endpoint is 0.14 mg/L (200 ppm) for this event.  No passive mitigation measures were taken into account in evaluating this ACS.  The ammonia spill is assumed to continue for two minutes before being stopped by manual or automatic means.  
 
 
4.  The general accidental release prevention program and specific prevention s 
teps: 
 
The facility developed prevention program elements based on the Federal EPAs Accidental Release Prevention Plan and OSHAs Process Safety Management (PSM) regulation.  This facility was designed  and constructed to comply with applicable state and industry codes. 
 
 
5.  Five-year accident history: 
 
In the last five years there have been no accidents involving, or accidental releases of ammonia that resulted in any deaths, injuries, or significant property damage on site; or known off-site deaths, injuries, evacuations, sheltering in place, property damage, or environmental damage.   
 
 
6.  The emergency response program: 
 
The facilitys emergency response program is based upon OSHAs HAZWOPER standard.  At this site, employees are trained to recognize emergencies and initiate emergency response from the LEPC and outside agencies.  They have been trained to OSHAs First Responder Awareness Level.  The employees receive annual refresher training in their role in the emergency plan. 
 Emergency response activities have also been coordinated with the Hennepin Fire Department for fires related to the flammable process.  Periodic drills are conducted to review the effectiveness of our emergency procedures.   
 
7.  Planned changes to improve safety: 
 
At this time, there are no major administrative, operational, process, or equipment changes planned for this facility.
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