What philosophies are refineries using to design hydrofluoric acid dump systems for their HF alkylation unit?
Is the dump system for HF or HF and hydrocarbon? Does the system dump to a vented or to a closed receiving vessel? What is the vent pressure if the acid receiving vessel is vented? Should the HF be pressure-transferred or pumped? RATERMAN: Our design philosophy is to transfer the total acid inventory to a remote vented drum within 5 min. The drum is vented through a caustic scrubber. The drum pressure will depend upon a number of operating conditions, but basically it floats on the scrubber, which is not pressure controlled, but vented to the flare system. Pressure transfer is used so that the dumping will not be dependent upon the operation of a pump. STEGELMAN: Our current design philosophy for an HF acid emergency dump system for an alkylation unit is to provide for the transfer of acid from the unit to remote storage in 10 min. The dump system is for both HF acid and hydrocarbon. The system dumps to a vented receiving vessel that is initially maintained just above atmo-spheric pres