Patent DE-102007035301-A1 (DE)
Title: Method for treating raw gas produced by pressure gasification of solid fuels for manufacturing synthesis gas or hydrogen, comprises subjecting the grained fuels at a head of a pressure carburetor with ash- and water content
Inventor: SCHMITT GERHARD
IPC: C10J3/20
Filed: 2007-07-27
Abstract: The method for treating raw gas produced by pressure gasification of solid fuels for manufacturing synthesis gas or hydrogen, comprises subjecting the grained fuels at a head of a pressure carburetor (1) with ash- and water content (50 wt.%) in counter flow to a gasification agent containing water vapor and oxygen, downwardly guiding over a rotary grid (11) from the bottom in the pressure carburetor at a pressure of 2-100 bar under the influence of gravitational force in the form of a fluidized bed (4) slowly through the carburetor and then drying, smoldering, gasifying and combusting. The method for treating raw gas produced by pressure gasification of solid fuels for manufacturing synthesis gas or hydrogen, comprises subjecting the grained fuels at a head of a pressure carburetor (1) with ash- and water content (50 wt.%) in counter flow to a gasification agent containing water vapor and oxygen, downwardly guiding over a rotary grid (11) from the bottom in the pressure carburetor at a pressure of 2-100 bar under the influence of gravitational force in the form of a fluidized bed (4) slowly through the pressure carburetor and then drying, smoldering, gasifying and combusting one after the other at a temperature below the ash melting point. The formed ash is discharged in an ash lock over the rotary grid and through an intermediate chamber (14) and is discharged from the ash lock. The ashes containing hydrogen, carbon monoxide, carbon dioxide, water, methane and nitrogen and/or raw gas withdrawn from the components of hydrogen sulfide, carbonyl sulfide, ammonia, hydrocarbon (C nH m) and traces of other compounds such as hydrogen cyanide, carbon disulfide, metal carbonyl, mercaptan, naphthalene, thiophene and organic sulfide are quenched with water at the upper part of the pressure carburetor at 300-800[deg] C by using waste heat for vapor production, subsequently saturated with a washing liquid and then cooled up to the dew point of the raw gas depending of the pressure and water vapor content. The unwanted components of carbon dioxide, hydrogen sulfide, carbonyl sulfide, hydrogen cyanide, ammonia and organic sulfide compounds, metal carbonyl and hydrocarbon (C nH m) contained in the cooled raw gas are physically absorbed at +10 to -80[deg] C. The extracted clean gas is used as synthesis gas for the ions of methanol and ammonia and oxo ion or Fischer-Tropsch synthesis or for producing hydrogen. The gas condensate of tar and dust formed during quenching and cooling of the raw gas is separated from the clean gas by gravitational force. The tar and low-dust gas condensate of phenol with a solvent is extracted from the gas condensate of tar and dust. The phenol-free gas condensate of ammonia is driven off from the tar and low-dust gas condensate of phenol. The ammonia-free gas condensate is introduced in a biological processor. The brine containing non-degradable materials derived from the biological processor is sprayed in the ashes in the intermediate chamber between the rotary grid and the ask lock. The temperature of ashes averaged at 20[deg] C is higher than the average temperature of the gasification agent means introduced into the pressure carburetor over the rotary grid. The quantity of the brine sprayed in the ashes is regulated in dependent of the gas production capacity of the pressure carburetor. The saturated water vapor extracted during spraying of the brine in the ashes is used as gasification agent for the gasification of the solid fuels. The quenched raw gas is subjected to a gas conversion by using the water vapor contained in it. The oil, tar and low-dust of the gas condensate are filtered before extracting the phenol. The ashes are cooled with the brine or with process wastewater. An independent claim is included for a device for treating raw gas produced by pressure gasification of solid fuels for manufacturing synthesis gas or hydrogen.