Delayed coker unit

Feeds and products from a delayed coker unit (using different feeds) ... 

A major fire that resulted in 65 million in property damages occurred early in the morning (4 21 A.M.) on August 2, 1993. The central unit of three delayed coker units was the origin of the fire. Each of the three units consisted of four 100-ft. metal coke drums mounted about 40 ft. above grade. The sustained, intense fire caused other pipes in the area to rupture, releasing more hydrocarbons. Over 95 fire brigade members battled the fierce fire for nearly three hours. [21] The fire killed three people. 

A typical delayed coker unit consists of coking, fractionation and blowdown sections, along with coke handling facilities. Coker gas is either processed in a dedicated vapor recovery unit or may be sent for processing, together with other gases, to a centralized vapor recovery unit. 

According to the chemical safety alert Hazards of Delayed Coker Unit (DCU) Operations (US EPA, 2003), some actions have been reported as beneficial to diminish the occurrence of incidents associated with incorrect valve activation due to mistaken coke drum or module identification. Some of the actions Usted in the referred safety alert are provide interlocks for valves that are manually operated as part of the switching/decoking cycle to avoid unanticipated valve movement provide interlocks for automated or remotely activated valve switching systems . These recommended actions can be achieved with the definition of set of permissive logics to prevent inadvertent valve operations. This set of logics can serve as an automated decision support system for the coke drum cycle. 

United States Environmental Protection Agency. 2003. Hazards of Delayed Coker Unit (DCU) Operations, Chemical Emergency Preparedness Office (5104-A), EPA-550-F-03-001, August, 2003. 

Figure 13.9 shows the four delayed coker units operated by Conoco, Immingham/England, which have a production capacity for 300,000 tpa of premium coke. 

Chem. Descrip. Silicone antifoam Uses Antifoam for delayed coker units... 

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