Source:
Terre Haute Tribune-StarA faulty flange resulted in synthetic gas exploding and killing two workers Monday at SG Solutions, a coal gasification plant north of Terre Haute.
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The two men, members of Boilermakers Local 374, were working about 150 feet in the air on the eighth deck of a coal gasifier, which is used in the process of turning coal into gas. The men were tightening bolts on the flanged opening, similar to a manhole cover, when the flange failed, causing an explosion, said Richard Payonk, plant manager.
“Our process runs at 400 pounds of pressure producing a synthetic gas, and consequently, when that flanged opening failed, it did release the contents of the gasification facility,” Payonk said. “At 400 pounds of pressure, that is a fairly violent release.
“At this time, we don’t have further information on the cause or root cause of that particular failure; that will come out in the investigation in days to come. Our first and foremost priority of course is our thoughts and prayers with the families of these workers, who are our friends. We are a very close-knit group here at the plant,” Payonk said.
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If I were OSHA, I would be demanding to see the work order they were operating under and ask why they were bolting a flange on a vessel operating at 400 psi. There are things called "lockout/tagout procedures" for a reason.