Liquid fuels atmospheric tanks

UL 2244, Standard for Aboveground Flammable Liquid Tank Systems, covers factory-fabricated, preengineered aboveground atmospheric tank systems intended for dispensing flammable or combustible liquids, sucn as gasoline or diesel fuel, into motor vehicles, generators, or aircraft. 

This evaporation increases the pressure on the tank wall and the gaseous hydrogen must be vented to the atmosphere to keep the tank from rupturing. During tests at the Los Alamos National Laboratory a liquid hydrogen fueled vehicle tank of liquid hydrogen evaporated away in about 10 days. 

This will generally be tr-ue as we proceed to look at other alkanes as the number of carbon atoms increases, so does the boiling point. All the alkanes with four car bons or less are gases at room temperature and atmospheric pressure. With the highest boiling point of the three, propane is the easiest one to liquefy. We are all faniliar- with propane tanks. These are steel containers in which a propane-rich mixture of hydrocar bons called liquefied petroleum gas (LEG) is maintained in a liquid state under high pressure as a convenient clean-burning fuel. 

Propane can be stored as liquid in pressurized (approximately 15 atmospheres) storage tanks and/or at cold temperatures and vaporizes to a gas at atmospheric pressure and normal temperatures. This makes it possible to store a large volume of propane as a liquid in a relatively small volume propane as a vapor occupies 270 times the volume of propane in liquid form. This makes liquid propane an ideal fuel for transport and storage until needed. 

A California statue requiring hazardous materials management was passed in 1985 (24), but guidance for compliance for industries covered by the act was not issued until 1988 (25). A revised standard, which became effective in January of 1994 (26), applies to facilities handling any of 128 toxic materials flammable liquids and gases in quantities of 10,000 lb (4.541) or more, except where used as fuel or in atmospheric pressure, ambient temperature tanks and explosives. 

PSM applies to a process involving a chemical at or above the specified threshold quantities listed in 1910.119, Appendix A, and also listed in Table 3.9. The requirements of the rule are also applicable to processes that involve a flammable liquid or gas on-site, in one location, in a quantity of 10,000 lb or more, except for hydrocarbon fuels used solely for workplace consumption as a fuel, or flammable liquids stored in atmospheric pressure tanks. 

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