Method and device for producing synthesis by partial oxidation of slurries made from fuels containing ash with partial quenching and waste heat recovery

Abstract

A method and a device for the gasification of solid fuels such as bituminous coal and coke such as bituminous coal, lignite, and biomass, as well as petroleum coke, that are finely ground and mixed with water or oil to make fuel-liquid suspensions, so-called slurries, and their gasification together with an oxidizing medium containing free oxygen by partial oxidation at pressures between atmospheric pressure and 100 bar, and at temperatures between 1200 and 1900° C., in an entrained flow reactor. The method includes the steps of slurry preparation and infeed to the reactor, gasification in an entrained flow reactor with cooled reaction chamber contour, partial quenching, waste heat recovery, and wet or dry dust separation, with the crude gas being pretreated so that it can be fed to other technological steps such as crude gas conversion or desulfurization.

1 . A method for the gasification of fuels such as bituminous coals and cokes such as bituminous, lignite, biomass, and petroleum coke in the entrained flow with an oxidizing medium containing free oxygen, the method comprising the following steps: 
 slurrying a pulverized fuel with a grain size <200 μm with water with added surfactant, to obtain a fuel-in-water slurry with a solids concentration of 40-70 wt. %;    bringing the slurried fuel to a gasification pressure of 100 bar by pumping, for which the slurry is preheated to temperatures up to 400° C.;    feeding the fuel to the reactor through a supply pipe together with an oxidizing medium containing free oxygen;    subjecting the fuel to partial oxidation in the reaction chamber at pressures between atmospheric pressure and 100 bar, the reaction chamber having a contour confined by a cooling shield;    melting ash of the fuel;    transferring the melted ash through a discharge device to a quenching chamber of a quenching cooler along with hot crude gas;    partially quenching the crude gas in the quenching cooler with cooling of the crude gas to temperatures between 700 and 1,100° C.;    cooling the partially quenched crude gas in a waste heat boiler to temperatures between 150 and 400° C. with generation of steam;    subjecting the cooled crude gas to a crude gas scrubber and partial condensation, or to dry mechanical dust separation by centrifugal force or filtration, to separate entrained dust; and    sending the cooled gas freed of dust to additional treatment steps.    
     
     
         2 . A method pursuant to  claim 1 , wherein a crude gas scrubber is used, and the crude gas scrubber is a single- or multiple-stage Venturi scrubber.  
     
     
         3 . A method pursuant to  claim 2 , wherein the Venturi scrubber is supplied with fresh water or recycled condensates that result from the cooling of the gas.  
     
     
         4 . A method pursuant to  claim 1 , wherein the waste heat boiler is operated at temperatures of 700 to 1,100° C.  
     
     
         5 . A method pursuant to  claim 2 , wherein the crude gas scrubbing takes place at temperatures of 150 to 300° C.  
     
     
         6 . A method pursuant to  claim 2 , wherein the Venturi scrubber is supplied with circulated water or recycled condensate.  
     
     
         7 . A method pursuant to  claim 1 , wherein the fuel is supplied to the reactor as a fuel-in-water slurry.  
     
     
         8 . A method pursuant to  claim 1 , wherein the fuel is supplied to the gasification reactor through one or more burners.  
     
     
         9 . A method pursuant to  claim 1 , wherein granulated slag from the quenching cooler is discharged through one or more outlets from the quenching cooler.  
     
     
         10 . A method pursuant to  claim 1 , wherein the partially quenched gas leaves the quenching cooler through one or more gas outlets.  
     
     
         11 . A method pursuant to  claim 1 , wherein one or more varieties of coal are gasified at the same time.  
     
     
         12 . A method pursuant to  claim 1 , wherein the amount of slurry in the supply pipe is measured, monitored, and regulated.  
     
     
         13 . Device for gasification of fuels such as bituminous coals and cokes such as bituminous, lignite, biomass, and petroleum coke in the entrained flow with an oxidizing medium containing free oxygen, comprising: 
 a system for producing and feeding slurry;    a reactor for the gasification of supplied powdered fuel with an oxidizing medium containing free oxygen, comprising a supply pipe for the slurried fuel and a line for the oxidizing medium, burners for feeding the slurried fuel and oxidizing medium into a reaction chamber of the reactor, said reaction chamber having a cooling shield consisting of water-cooled pipes welded gas-tight, and an outlet device;    a quenching cooler with no internals connected to the reactor via the outlet device, the quenching cooler having nozzles arranged in one or more nozzle rings through which is sprayed water for partial quenching, said nozzles being integrally incorporated in an inner jacket;    a waste heat boiler following the quenching cooler; and    equipment for purifying the gasified fuel.    
     
     
         14 . A device pursuant to  claim 13 , wherein a reaction chamber of the quenching cooler is connected directly to the waste heat boiler, in which heat of the crude gas is utilized through tubes to produce steam, and wherein there are discharge openings in a bottom of the waste heat boiler for crude gas and for slag withdrawal with a water bath.  
     
     
         15 . A device pursuant to  claim 13 , further comprising a crude gas scrubber and a partial condensation system following the crude gas scrubber for purification.  
     
     
         16 . A device pursuant to  claim 15 , wherein the crude gas scrubber is a single- or multiple-stage Venturi scrubber.  
     
     
         17 . A device pursuant to  claim 13 , further comprising a mechanical dry dust separator for gas purification.  
     
     
         18 . A device pursuant to  claim 15 , wherein there are further gas treatment stages connected in line after the water scrubber and partial condenser or the mechanical dry dust separator.  
     
     
         19 . A device for gasification of fuels such as bituminous coals and cokes such as bituminous, lignite, biomass, and petroleum coke in the entrained flow with an oxidizing medium containing free oxygen, comprising: 
 a system for producing and feeding slurry;    a reactor for gasification of supplied fuel dust with an oxidizing medium containing free oxygen, the reactor comprising a supply pipe for receiving slurried fuel and a line for the oxidizing medium, said slurried fuel and oxidizing medium being fed by burners into a reaction chamber of the reactor, said reaction chamber comprising a cooling shield made of water-cooled pipes welded gas-tight and a discharge device;    a quenching cooler connected to the discharge device;    a waste heat boiler connected to the quenching cooler via a transfer line for receiving partially cooled crude gas, said boiler being equipped with boiler tubes and utilizing heat of the crude gas to produce steam;    a crude gas scrubber and a partial condensation system following the crude gas scrubber, or a mechanical filtration dust separator.    
     
     
         20 . A device pursuant to  claim 19 , further comprising water baths in both the quenching cooler and the waste heat boiler, in which water baths cooled slag is collected.  
     
     
         21 . A device pursuant to  claim 19 , further comprising devices for discharging slag on both the quenching cooler and the waste heat boiler.