Published on 14/09/23 644 Views

While an operator was working near an LPG amine absorber tower at an unsaturated gas plant within a fluid catalytic cracking unit, he noticed a gas leak from a 150mm crack near a circumferential weld at the tower's base. Attempting to close the main inlet valve, he observed the leak escalating, prompting an evacuation. As firefighters arrived, the crack rapidly expanded, releasing a substantial amount of propane/butane that ignited, causing a powerful explosion. The upper section of the vessel, about 14 meters high, was propelled 1 km away, striking a power transmission tower. Power loss disabled an electric motor-driven firewater pump, and damage to a fire hydrant further reduced fire water pressure from the remaining pumps. The tower was part of a system to remove hydrogen sulphide from mixed LPG using monoethanol amine solution. Constructed from carbon steel, the vessel had been in service since 1970 and underwent periodic inspections and modifications due to corrosion and blistering issues.

Ask yourself and your crew:

How can something like this happen here (e.g. on our site)?
What safety measures (i.e. procedures, controls/barriers) do we have in place to mitigate the risk?
How do we know the risk controls/barriers are working?
What improvements or changes should we make to the procedures, controls/barriers or the way we work?

Original content courtesy of IChemE Safety Centre