Monday, July 1, 2013

Liquid Natural Gas Disasters - A History of Accidents

It is often said by the natural gas liquids industry that accidents are rare.  However, there is, in fact, a long history of accidents.  Further, when accidents do occur, they are often catastrophic.  The Appomattox, Virginia Natural Gas Pipeline Explosion Sept 14, 2008, for example, left a 34 wide and 15 foot deep crater with a burn zone of 1125 feet in diameter.  Twenty-three 23 families had to leave their homes.  Houses were destroyed, and 5 were injured.  The pipeline was 30 inches in diameter, installed in 1955 and was operating at 799 psi at the time of the explosion - Per Jeffery Wiese, Associate Administrator for Pipeline Safety, Sept 25, 2008

Video of the Appomattox Explosion


Wikipedia.org lists a comprehensive history of accidents worldwide, as well as in the US, and the information below was taken from this source: http://en.wikipedia.org/wiki/List_of_pipeline_accidents_in_the_United_States

1973 In Austin, Texas, a natural gas liquids (NGL) pipeline ruptured due to an improper weld. A passing car or truck set off a vapor cloud explosion and fire. Six people were killed, and 2 others injured. (February 22, 1973)

1975 A natural gas liquids (NGL) pipeline ruptured due to previous mechanical damage at Devers, Texas. 4 people were killed in a following vapor cloud fire. The pipeline had been damaged when a valve was installed on the pipeline. (May 12, 1975)

1976 A repair crew working on natural gas gathering compressor station at Cedardale, Oklahoma on January 7, opened the wrong valve in an attempt to increase gas flow. Natural gas & Natural Gas Liquids flow out of an open 12-inch pipeline, and were ignited by an open flame heater. 5 of the crew were killed, and 2 seriously burned.

1976 An LPG/NGL pipeline ruptured near Whitharral, Texas, leading to vapor cloud fire that killed one, severely burning 4 others who later died, destroyed two homes, and burned an area about 400 yards wide. A Low Frequency Electrical resistance weld (LF-ERW) seam failure is suspected for the failure. From January 1968 to the date of the Whitharral accident, 14 longitudinal pipe seam failures had occurred on that pipeline system, which resulted in 6 other fatalities, and the loss of over 60,000 barrels (9,500 m3) of LPG.(February 25, 1976)

1980 A road grader ruptured an NGL pipeline in Aurora, Colorado on August 11. Firefighters had barely evacuated residents in the area when the vapors exploded, burning one firefighter.

1981 A 12-inch diameter pipeline near Ackerly, Texas, was hit by a rathole drill on September 27, releasing an ethane-propane mix. There was then an explosion & fire that killed 4 people.

1984 An 8-inch NGL pipeline near Hurst, Texas, was hit by a front loader, and the escaping gases ignited, causing burns to the equipment operator. (February 28, 1984)

1987 In July, a fishing vessel, working in shallow waters off Louisiana, the menhaden purse seiner Sea Chief, struck and ruptured an 8" natural gas liquids pipeline operating at 480 psi. The resulting explosion killed two crew members. Divers investigating found that the pipe, installed in 1968, was covered with only 6" of soft mud, having lost its original 3-foot (0.91 m) cover of sediments.

1987 Construction equipment hit a LPG/NGL pipeline near Rochester, Iowa on June 26, killing one person, and injuring 2 others.

1988 A pair of MAPCO LPG/NGL pipelines failed in an explosion south of Topeka, Kansas on July 22. 200 nearby residents had to be evacuated, and there was serious damage to US Route 75 nearby from the explosion & following fire. An ERW seam selective corrosion failure in one of the pipelines caused the failure.

1989 On November 16, propane from a storage cavern for a pipeline escaped and ignited in Jasper, Missouri, forcing 1,000 people to evacuate. A rail line and a highway were also closed.

1992 On December 3, pipeline company workers ruptured a natural gas liquid (NGL) pipeline, causing a vapor cloud to drift across I-70 near Aurora, Colorado. The Cloud later ignited, burning 6 motorists.

1998 On December 3, a natural gas liquids pipeline near Moab, Utah failed and ignited near Highway U-191, injuring 4 pipeline workers. Asphalt in the road was melted, and traffic was stopped.

1994 On February 1, the third explosion in 7 years hit a LPG/NGL pipeline Terminal in Iowa City, Iowa. 11 workers at the Terminal escaped injury, and 6 families within 1 1/2 miles of the Terminal were evacuated. The 2 previous explosions were in 1987 and 1989.

1999 A Lakehead Pipeline was damaged by outside force on November 2, near Meridian, Michigan. Of about 223,000 gallons of NGL's spilled, about 115,000 gallons were recovered.

2000 A Bulldozer ruptured a 12-inch diameter NGL pipeline on Rt. 36, south of Abilene, Texas, on September 7. An Abilene police detective, with 21 years of service, was severely burned when the vapors ignited, and later died. Nearby, a woman saved herself by going underwater in her swimming pool. Her house was destroyed by the explosion and fire. The owner of the pipeline, ExxonMobil, was later fined by the Texas Railroad Commission for the pipeline not being marked.

2004 On November 8, a NGL pipeline failed in a housing division in Ivel, Kentucky. The vapor cloud from the leak ignited, seriously burning a Kentucky State Trooper evacuating those living in the area. Eight others were injured and five homes were destroyed. The pipeline, only 65 miles (105 km) long, had 11 previous corrosion failures.

2010 On February 25, a natural gas liquids (NGL) pipeline ruptured near Pond Creek, Oklahoma, releasing over 575,000 US gallons (2,180,000 L) of NGL's, and forcing road closures. There was no fire.

2011 An 8-inch NGL pipeline failed in Romeoville, Illinois on May 14, leaking about 4200 gallons of butane. Corrosion inside a casing under a road was the cause of the failure. Corrosion only 2.5 feet from the failure had been seen by a smart pig run in 2007, but was not within action limits at the time.

2011 An Enterprise Products Partners pipeline carrying natural gas liquid leaked approximately 140,000 gallons of fuel into an Iowa section of the Missouri River. The pipeline typically transports 33,600 barrels of NGLs every day. It’s part of Enterprise’s mid-America, 2,800-mile network serving propane markets, refineries, and the petrochemical industry throughout the Midwest.  Source: http://www.propane.pro/blog/floods-responsible-ngl-leak-missouri-river1608/

2012 Williams (NYSE: WMB) based in Tulsa, Okla., said that a leak on the 4-inch pipeline in Denver, CO that carries natural gas liquids (NGLs) from one of the company’s natural gas processing plants, started on Dec. 20, 2012 and was stopped on Jan. 3, 2013. A broken pressure gauge on a valve, part of a pipeline carrying natural gas liquids, is the cause of the leak. Source: http://www.bizjournals.com/denver/blog/earth_to_power/2013/04/williams-ids-source-of-ngl-spill-in.html?page=all

2013 A flash fire at a pipeline gas compressor station broke out when natural gas liquids ignited in Tyler County, West Virginia on April 11, seriously burning 3 workers, two of whom later died. The workers were performing pipeline pigging operations.

2013 An explosion took place at Williams Chemical Plant in Ascension Parish, Louisiana State Police said, and a fire after the explosion was contained and extinguished later in the day. One worker died, and 73 were injured.  Subsequent lawsuits alleged the company failed to properly train workers and provide safety measures.  Reportedly, dozens of workers were trapped on the plant grounds until workers were able to break through locked gates.