초록 ▼

In an improved system for recovering heat from a combustion gas produced by burning wastes, the combustion gas or combustible gas produced by partial burning of the wastes subjected to dust filtration in a temperature range of 450-650.degree. C. at a filtration velocity of 1-5 cm/sec under a pressur

In an improved system for recovering heat from a combustion gas produced by burning wastes, the combustion gas or combustible gas produced by partial burning of the wastes subjected to dust filtration in a temperature range of 450-650.degree. C. at a filtration velocity of 1-5 cm/sec under a pressure of from -5 kPa (gage) to 5 MPa before heat recovery is effected. The dust filtration is preferably performed using a filter medium which may or may not support a denitration catalyst. Heat recovery is preferably effected using a steam superheater. The dust-free gas may partly or wholly be reburnt with or without an auxiliary fuel to a sufficiently high temperature to permit heat recovery. The combustion furnace may be a gasifying furnace which, in turn, may be combined with a melting furnace. If desired, the reburning to a higher temperature may be performed under pressure and the obtained hot combustion gas is supplied to a gas turbine to generate electricity, followed by introduction of the exhaust gas from the gas turbine into a steam superheater for further heat recovery. The system can raise the temperature of superheated steam to a sufficient level to enhance the efficiency of power generation without possibility of corrosion of heat transfer pipes by the combustion gas or combustible gas.

대표청구항 ▼

[ What is claimed is:] [1.] A method of recovering heat and generating power from wastes, said method comprising:gasifying said wastes at a low temperature to thereby produce combustible gas;burning said combustible gas at high temperature to produce combustion gas containing at least one of alkali

[ What is claimed is:] [1.] A method of recovering heat and generating power from wastes, said method comprising:gasifying said wastes at a low temperature to thereby produce combustible gas;burning said combustible gas at high temperature to produce combustion gas containing at least one of alkali metal chlorides, calcium chloride, copper oxide and copper chloride;cooling said combustion gas in a waste heat boiler to produce steam;subjecting the thus cooled combustion gas to dust filtration at a temperature of from 450-650.degree. C. to thereby remove any said alkali metal chlorides, said calcium chloride, said copper oxide and said copper chloride as solidified materials, and thereby producing filtered combustion gas;reburning said filtered combustion gas with auxiliary fuel to thereby reheat the combustion gas to a temperature sufficient to permit heat recovery therefrom;introducing the thus reheated combustion gas into a steam superheater, and passing said steam through said steam superheater, thereby recovering heat from said combustion gas and superheating said steam; andintroducing the thus superheated steam into a steam turbine and therein generating power.