Scenario: Fire and Explosion in Process Industry Problem: Consider a butadiene storage vessel in a tank area containing butadiene, cyclohexane, isopentane, styrene, and isopropene. The maximum butadiene storage capacity is 250,000 gals. The normal pressure of the butadiene storage vessel is 350 psig, with the relief valve set at 65 psig. The butadiene storage is diked separately from the other materials. The butadiene storage area is equipped with a chilled glycol cooling system that can be operated from an emergency generator if necessary. The transfer operations in and out of storage are monitored by computer control with emergency shutdown capability. The vapor space in the vessel is inerted. Operating instructions are updated, and the system has been through a recent reactive multiple chemicals review. The storage system is remotely operated emergency block valves on all transfer lines into and out of the tank. The storage area has the required drainage to direct a spill away from the tank. Backflow protection has been installed and is tested to prevent backflow into the transfer line and storage. Loss control features include combustible gas detectors installed around the containment area and transfer system. A diesel-driven fire pump can handle the emergency demand for 8 hr. A water deluge system has been installed around the storage tank and transfer pump. The specific gravity of the butadiene is 0.62

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chemical process safety

determine loss control creddit factors

C1,C2,C3

LOSS CONTROL CREDIT FACTORS 1. Process Control Credit Factor (C1) C1 Value(3) 2. Material isolation Credit Factor (C2) C2 Value(3) 3. Fire Protection Credit Factor (C3) Ca Value(3)