Patent ID: 7947095
Filing Date: 2011-05-24
Classification: C10J,F23G

Abstract:
1. A method of gasifying carbonaceous material, said method comprising the steps of: (a) introducing carbonaceous material into a gasification reactor; (b) introducing primary gasification gas into a bottom portion of the gasification reactor and secondary gasification gas above the bottom portion of the gasification reactor, and combusting the primary gasification gas, the secondary gasification gas and the carbonaceous material in the gasification reactor, whereby a portion of the carbonaceous material gasifies to product gas, and ash containing residual carbon is generated; (c) discharging the product gas and fly ash containing residual carbon entrained therewith from the gasification reactor to a product gas channel connected to the gasification reactor; (d) conducting the product gas and the fly ash containing residual carbon along the product gas channel to a particle separator, where fly ash containing residual carbon is separated from the product gas; (e) introducing separated fly ash containing residual carbon and oxygen-containing gas into a cyclone combustor so as to combust the residual carbon, generating exhaust gas and ash, which are separately removed from the cyclone combustor; (f) conducting a portion of the exhaust gas from the cyclone combustor to the gasification reactor and introducing the portion of the exhaust gas above the bottom portion of the gasification reactor, to act as the secondary gasification gas; and (g) adjusting the temperature of the cyclone combustor to remain below 950° C. and below the melting temperature of the ash, by adjusting in step (e) the rate of introduction of the oxygen-containing gas into the cyclone combustor to be in an amount of at least 1.5 times the stoichiometric amount.