Refinery Explosion Probe Zeroes In on Acid Use, Corroded Pipe

Pipes corroded from hydrofluoric acid at the Philadelphia Energy Solutions Refinery were partially responsible for a June explosion and fire that knocked out much of its refining capacity, the U.S. Chemical Safety Board says.

The independent agency released an update on the June 21 incident at the plant, the biggest of five refineries in the Northeast, according to Bloomberg data.

“We are lucky there were no serious injuries or fatalities,” CSB Interim Executive Authority Kristen Kulinowski said in a news release.

According to the agency, a pipe elbow that had corroded to about half the thickness of a credit card ...