Patent NZ-567582-A (NZ)
Title: Process and system for gasification with in-situ tar removal having a gas conditioning module
Inventor: PAISLEY MARK A
IPC: C07C4/04
Filed: 2006-10-23
Abstract: A method for converting a synthesis gas containing hydrocarbons is disclosed, wherein the method comprises the steps of:providing both an indirectly heated sealed gasification module for generating said synthesis gas from a carbonaceous fuel, and a combustion module for contributing to an operation temperature of said gasification module;providing an in situ gas conditioning module for receiving said synthesis gas from said gasification module and for operating at said operation temperature; conditioning said synthesis gas in said gas conditioning module to minimize a tar content therein; providing a fluidized bed of heat transfer material containing at least a portion by weight of a catalytically active heat transfer material; contacting said heat transfer material with said synthesis gas in said gas conditioning module thereby enabling said step of conditioning by heating the carbonaceous fuel to an operation temperature of 825 Deg. C or more in an air-free environment within the sealed gasification module without any combustion reaction in the presence of steam with formation of gas, including hydrocarbons and tars, and solid particles; and circulating said heat transfer material from said combustion module where said heat transfer material is heated to maintain an operation temperature, to said gas conditioning module where at least said step of contacting occurs at said operation temperature, and to said gasification module. The disclosure also relates to a system for converting a synthesis gas containing hydrocarbons, wherein the system comprises: an indirectly heated, sealed gasification module means for generating from a carbonaceous fuel synthesis gas, solid particles and tars by heating the incoming carbonaceous fuel to an operation temperature of about 825 Deg. C or more in an air-free environment in a circulating fluidized bed of heat transfer material without any combustion reaction in the presence of steam; in situ gas conditioning module means for receiving said synthesis gas from said gasification module and for operating at said operation temperature at which the condensable hydrocarbons/tars are reacted with steam input to separate them of the synthesis gas and obtain conditioning synthesis gas, wherein said means of conditioning said gas in said gas conditioning module further comprises at least one means for cracking said hydrocarbons and means for shifting said gas, thereby producing a synthesis gas containing a hydrocarbon:carbon monoxide ratio having a positive hydrogen balance; means for providing a steam supply to both said gas conditioning module means; a combustion module for heating a thermal transfer material and for circulating said heated thermal transfer material to said gas conditioning module for contributing to an operation temperature of said gasification module before circulating said thermal transfer materials to said gasification module and means for conditioning said gas which are included in said gas conditioning module means to minimize a tar content therein.