Hydrofluoric acid (HF) leaked from an alkylation unit at BP Plc’s 406,570-barrels-per-day refinery in Texas City, TX, Tuesday, triggering alarms in the plant and warnings to area residents, company and city officials said.
No one suffered an injury at the refinery, the fifth-largest in the United States, or in the surrounding community, the officials said.
“We have a small leak of hydrofluoric acid at the refinery,” said BP spokesman Tom Mueller. “Water is being sprayed on it. We expect to secure the leak shortly.”
Water cannons surrounding alkylation unit 3 triggered when monitors detected the leak, Mueller said. Workers in the refinery not battling the leak ended up ordered to shelter in place.
Officials still don’t know the cause of the leak, and Mueller declined to say how the leak affected gasoline production.
Hydrofluoric acid can damage skin, eyes, lungs, bones and the heart in humans. Exposure can be fatal, and HF acid can form into vapor clouds able to spread over large distances.
Water cannons prevent a vapor cloud from forming. The HF clings to water droplets and falls to the ground. Workers trying to secure a leak wear protective clothing.
Environmental groups and the United Steelworkers union, which represents most U.S. refinery workers, have campaigned to replace HF alkylation units with units using sulfuric acid in order to prevent HF vapor cloud exposure.
Texas City officials notified residents of the leak shortly before 9 a.m. local time. There were no orders for residents to remain indoors.
BP’s Texas City plant was the site of the worst refinery disaster in the past decade when 15 workers died and 180 others injured by an explosion on March 23, 2005.
BP’s term of probation for a violation of federal environmental law in the 2005 explosion ended this month.
An alkylation unit uses refining byproducts to make octane-boosting components that add into gasoline.
The U.S. Chemical Safety Board and U.S. Occupational Safety and Health Administration are investigating an HF acid leak earlier this month at Citgo Petroleum Corp’s 163,000-bpd Corpus Christi, TX, refinery.
An alkylation unit there was leaking for five months before spilling as much as 500 pounds of the hydrofluoric acid on March 5, the CSB said.
Leaks from a flange on the unit occurred as early as September, said Johnnie Banks, lead CSB investigator. The release persisted after maintenance and the unit stayed online while a clamp underwent a redesign, he said.
In addition, the CSB called a 2009 explosion on the HF alkylation unit at Citgo’s Corpus Christi plant a near-miss of widespread exposure of HF acid in a community surrounding a refinery.