Seconds From Disaster - Oil Fire In Texas
- 9 лет назад
The Texas City Refinery explosion occurred on March 23, 2005, when a hydrocarbon vapour cloud exploded at the ISOM isomerization process unit at BP's Texas City refinery in Texas City, Texas, killing 15 workers and injuring more than 170 others. The Texas City Refinery was the second-largest oil refinery in the state, and the third-largest in the United States with an input capacity of 437,000 barrels (69,500 m3) per day as of January 1, 2000.[1] BP acquired the Texas City refinery as part of its merger with Amoco in 1999.[2][3]
BP's own accident investigation report[4] stated that the direct cause of the accident was "[...]heavier–than-air hydrocarbon vapors combusting after coming into contact with an ignition source, probably a running vehicle engine. The hydrocarbons originated from liquid overflow from the F-20 blowdown stack following the operation of the raffinate splitter overpressure protection system caused by overfilling and overheating of the tower contents." Both the BP and the U.S. Chemical Safety and Hazard Investigation Board reports[5] identified numerous technical and organisational failings at the refinery and within corporate BP.
In 2011 BP announced that it was selling the refinery as part of its ongoing divestment plan to pay for ongoing compensation claims and remedial activities following the Deepwater Horizon disaster in 2010. The sale of the refinery was completed at the start of 2013 to Marathon Petroleum Corporation for US$2.5 billion.
The refinery was built in 1934, but had not been well maintained for several years.[7] Consulting firm Telos had examined conditions at the plant and released a report in January 2005 which found numerous safety issues, including "broken alarms, thinned pipe, chunks of concrete falling, bolts dropping 60 ft and staff being overcome with fumes." The report's co-author stated, "We have never seen a site where the notion 'I could die today' was so real."[8][9] The refinery had also had five managers in the six years since BP inherited it in its 1999 merger with Amoco.[10]
Typical isomerisation reaction
The ISOM plant isomerization at the site was designed for the conversion of low octane hydrocarbons, through various chemical processes, into higher octane rating hydrocarbons that could then be blended into unleaded petrol. One component of this ISOM site was a unit called the raffinate splitter. When operational, this 170-foot tall tower was used to separate out lighter hydrocarbon components from the top of the tower (mainly pentane and hexane), which condensed and were then pumped to the light raffinate storage tank, while the heavier components were recovered lower down in the splitter, then pumped to a heavy raffinate storage tank. It had an operational capacity of 45,000 barrels per day (bpd).
Remedial work had been started on the raffinate splitter from February 21, 2005. Two other turnaround[11] activities were also taking place at the adjacent Ultracracker Unit (UCU) and at the Aromatics Recovery Unit (ARU) at the same time.
In 1995 and again in 2002, site-wide temporary siting analysis reports had been created at the facility that established the agreed layout of trailers and other temporary structures. The next siting analysis was due to take place in 2007 and, therefore, any siting changes before then would be under the management of change (MOC) process. Plans were made late in 2004 to accommodate contractors due to work on the UCU in 2005 in nine single trailers and a single double-wide trailer adjacent to the ISOM process unit. Although the team carrying out this assessment had identified that the double-wide trailer would be less than 350 feet from the ISOM plant (and therefore had the potential to be susceptible to severe damage in the event of an explosion), they did not have the expertise to complete the Amoco workboat siting analysis, which was based upon the American Petroleum Institute standard "API 752".[12] A number of action items were created from this assessment, and according to the procedure, these had to be closed before the MOC could be approved and prior to the double-wide trailer being used. These two actions were still pending in March, 2005 but nevertheless, the double-wide trailer had already been in use by contractors from November, 2004. The remaining nine UCU contractor trailers arrived on site at the start of 2005, but these had not been included in the 2004 MOC, so the additional exposure risk of these new trailers being occupied in close proximity to the ISOM plant was never assessed.
BP's own accident investigation report[4] stated that the direct cause of the accident was "[...]heavier–than-air hydrocarbon vapors combusting after coming into contact with an ignition source, probably a running vehicle engine. The hydrocarbons originated from liquid overflow from the F-20 blowdown stack following the operation of the raffinate splitter overpressure protection system caused by overfilling and overheating of the tower contents." Both the BP and the U.S. Chemical Safety and Hazard Investigation Board reports[5] identified numerous technical and organisational failings at the refinery and within corporate BP.
In 2011 BP announced that it was selling the refinery as part of its ongoing divestment plan to pay for ongoing compensation claims and remedial activities following the Deepwater Horizon disaster in 2010. The sale of the refinery was completed at the start of 2013 to Marathon Petroleum Corporation for US$2.5 billion.
The refinery was built in 1934, but had not been well maintained for several years.[7] Consulting firm Telos had examined conditions at the plant and released a report in January 2005 which found numerous safety issues, including "broken alarms, thinned pipe, chunks of concrete falling, bolts dropping 60 ft and staff being overcome with fumes." The report's co-author stated, "We have never seen a site where the notion 'I could die today' was so real."[8][9] The refinery had also had five managers in the six years since BP inherited it in its 1999 merger with Amoco.[10]
Typical isomerisation reaction
The ISOM plant isomerization at the site was designed for the conversion of low octane hydrocarbons, through various chemical processes, into higher octane rating hydrocarbons that could then be blended into unleaded petrol. One component of this ISOM site was a unit called the raffinate splitter. When operational, this 170-foot tall tower was used to separate out lighter hydrocarbon components from the top of the tower (mainly pentane and hexane), which condensed and were then pumped to the light raffinate storage tank, while the heavier components were recovered lower down in the splitter, then pumped to a heavy raffinate storage tank. It had an operational capacity of 45,000 barrels per day (bpd).
Remedial work had been started on the raffinate splitter from February 21, 2005. Two other turnaround[11] activities were also taking place at the adjacent Ultracracker Unit (UCU) and at the Aromatics Recovery Unit (ARU) at the same time.
In 1995 and again in 2002, site-wide temporary siting analysis reports had been created at the facility that established the agreed layout of trailers and other temporary structures. The next siting analysis was due to take place in 2007 and, therefore, any siting changes before then would be under the management of change (MOC) process. Plans were made late in 2004 to accommodate contractors due to work on the UCU in 2005 in nine single trailers and a single double-wide trailer adjacent to the ISOM process unit. Although the team carrying out this assessment had identified that the double-wide trailer would be less than 350 feet from the ISOM plant (and therefore had the potential to be susceptible to severe damage in the event of an explosion), they did not have the expertise to complete the Amoco workboat siting analysis, which was based upon the American Petroleum Institute standard "API 752".[12] A number of action items were created from this assessment, and according to the procedure, these had to be closed before the MOC could be approved and prior to the double-wide trailer being used. These two actions were still pending in March, 2005 but nevertheless, the double-wide trailer had already been in use by contractors from November, 2004. The remaining nine UCU contractor trailers arrived on site at the start of 2005, but these had not been included in the 2004 MOC, so the additional exposure risk of these new trailers being occupied in close proximity to the ISOM plant was never assessed.