Gas Leak, Explosion, Fire Hit 2 South Bay Refineries

Two South Bay refineries suffered minor incidents last week. Neither resulted in injuries.

An explosion and fire hit Mobil’s Torrance refinery Wednesday. A leak of foul-smelling sulfur dioxide at the Ultramar refinery in Wilmington on Thursday forced the brief evacuation of about 750 workers--everyone at the plant who was not trying to control the leak.

The Mobil fire started about 7 p.m. Wednesday near a furnace used to heat hydrogen and naphtha. The fire started after a cap gave way in a pipe containing the volatile substances at pressures up to 500 pounds per square inch. The fumes ignited explosively when they reached the furnace flame, according to Torrance Fire Battalion Chief Bill Peterson.

The fire was extinguished in about 15 minutes after refinery employees closed off the line and then purged it with non-combustible nitrogen, Peterson said.

Mobil spokesman Greg Munakata said the incident happened while a unit that removes sulfur and nitrogen was being started up after a maintenance shutdown. He said repairs are expected to be completed in several days.

At the Ultramar refinery in Wilmington, a malfunction in a propane warmer caused some liquid propane--instead of gaseous propane--to reach a desulfurizing unit. The liquid fuel fouled the catalyst and prevented the unit from functioning properly about, at 10 a.m. Thursday.

Refinery officials shut down the sulfur plant and shunted sulfurous gases to an incinerator, which briefly released sulfur dioxide.

Marshall (Bud) Bell, Ultramar general manager of refining, said that as a precaution, the plant was cleared of all personnel not involved in shutting down the refinery. He said the incident was over in two to three minutes.