BLEVEs: Their causes, effects and prevention

If pressure vessels and their piping systems are properly designed, relief valve capacity should prevent a BLEVE due to simple pressure rise in closed vessels shell-full of liquid. Mechanically induced BLEVEs are preventable if the accident that caused the damage is preventable. However, the few recorded BLEVEs of this type have occurred in transportation accidents. Such accidents seem impossible to prevent. Possibly,different metal alloys with different strength, ductility, and notch-toughness may prevent some of these BLEVEs by changing the mode of tank failure. Fire-induced BLEVEs are a different problem. There are three obvious choices for prevention: 1. Prevent the fire; 2. Prevent the fire from heating the tank; and 3. Prevent the buildup of pressure within the tank. Preventing fires is always difficult. Some progress has been made in railroad transportation (head shields and shelf couplers on railroad tank cars). Goal: to prevent liquefied gas spills and fires following derailments.