METHOD OF INITIALIZATION OF STARTING OF COAL GASIFICATION UNIT

摘要

The method of this invention permits preheating a reactor such as a gasifier kiln while maintaining oxygen content in the kiln sufficiently low to prevent chloride induced stress corrosion cracking. …??A method is designed for initating operation of a coal gasification plant which includes a gasification reactor and gas cleaning apparatus fabricated in part from materials susceptible to chloride induced stress corrosion cracking caused by the presence of oxygen. …??The method comprises combusting a stoichiometric mixture of air and fuel to first produce an exhaust gas which is then diluted with steam to produce product gas which contains essentially no free oxygen. The product gas is introduced to heat the reactor to a temperature profile necessary to maintain autothermic operation of the gasfication process while maintaining air oxygen-free environment within the plant apparatus while chlorine is liberated from coal being gasified. …??While the above single stage preheating method is practical, from an economic standpoint, it would be preferably to expand this method by providing a first stage of preheating with only hot air up to 232 DEG C, a second stage of preheating by burning fuel and air to produce an exhaust gas which is tempered by air to provide a product gas having an initial temperature of 260 DEG C and which is increased up to 538 DEG C and providing a third stage comprising steps a. through h. as recited in proposed claim 1.