PRODUCTION OF CONCRETE ADMIXTURE FROM COAL ASH

摘要

PURPOSE:To provide a production method of a concrete admixture material from coal ash, which reduces generation of NOX and consumed less energy. CONSTITUTION:Coal is supplied from a coal hopper 24 to a combustion furnace 20, and coal ash from a coal ash hopper 23 and oxygen 37 are supplied. The coal an coal ash are used waste gas in which a part of the waste gas 34 extracted from back stream of a dust collector 27 is passed through a heat exchanger 25 and is raised to the temp., as high as transfer gas 36. Also a part 38 of the temp. raised waste gas is introduced to a coal ash hopper 23 to be used as temp. raising gas of the coal ash. Also the balance of the waste gas 34 is used as cooling gas for mixed gas at high temp. containing SiO2 vaporizing gas going out from the combustion furnace 20. Thus, since the waste gas is used in circulation as the transfer gas of the coal and coal ash and the cooling gas for high temp. mixed gas, N2 gas is not introduced to the high temp. combustion furnace 20 or a cooling part 22 and NOX is not generated. Also the waste gas 38 heated through the heat exchanger 25 is introduced to the coal ash hopper 23 to heat the coal ash.