Refrigerated ethylene tank

During a several-day outage of the refrigeration unit outage, the ethylene tank absorbed ambient heat and the internal pressure increased. The backup plan to cool by auto refrigeration as vapor escaped via the open relief valve was underway. As planned, a flow of steam was routed to the stack in hopes of safely dispersing the cold gases. 

Circulating this stream faster or slower through the refrigeration unit keeps the liquid ethylene temperature in balance with the change in temperature outside the tank. 

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