Gasification system and its use

Abstract

A gasification system that comprises a gasification reactor and a synthesis gas cooling vessel, and its use. The gasification reactor comprises a pressure shell for maintaining a pressure higher than atmospheric pressure; a slag bath located in a lower part of the pressure shell; and a gasifier wall arranged inside the pressure shell. The gasifier wall defines a gasification chamber wherein during operation the synthesis gas can be formed, a lower open part of the gasifier wall which is in fluid communication with the slag bath and an open upper end of the gasifier wall which is in fluid communication with the synthesis gas cooling vessel via a connecting conduit. The synthesis gas cooling vessel comprises an inlet for hot synthesis gas; an outlet for cooled synthesis gas; and means to directly contact liquid water with the hot synthesis gas as formed in the gasification reactor in use.

1 . A gasification system comprising a gasification reactor and a synthesis gas cooling vessel, wherein the gasification reactor comprises: 
 a pressure shell for maintaining a pressure higher than atmospheric pressure;    a slag bath located in a lower part of the pressure shell;    a gasifier wall arranged inside the pressure shell defining a gasification chamber wherein during operation the synthesis gas can be formed, a lower open part of the gasifier wall which is in fluid communication with the slag bath and an open upper end of the gasifier wall which is in fluid communication with the synthesis gas cooling vessel via a connecting conduit;    and wherein the synthesis gas cooling vessel comprises:    an inlet for hot synthesis gas;    an outlet for cooled synthesis gas; and    means to, in use, directly contact liquid water with the hot synthesis gas as formed in the gasification reactor.    
     
     
         2 . The system according to  claim 1 , wherein the synthesis gas cooling vessel has the inlet for receiving hot synthesis gas at its upper end and the outlet for cooled synthesis gas at its lower end, such that in use, a substantially downwardly directed flow path of synthesis gas will result and wherein in the flow path downwardly directed injecting means are present, said injecting means suited to inject a mist of water.  
     
     
         3 . The system according to  claim 1 , wherein the synthesis gas cooling vessel has an opening for receiving hot synthesis gas at its upper end and an outlet for cooled synthesis gas defining a flow path for synthesis gas there between, and wherein a water bath is present in the flow path of the synthesis gas.  
     
     
         4 . The system according to  claim 3 , wherein the outlet for cooled synthesis gas is fluidly connected to an inlet of a wet gas scrubber.  
     
     
         5 . The system according to  claim 4 , wherein the gas outlet of the wet gas scrubber is fluidly connected to an inlet of a water shift converter.  
     
     
         6 . The system according to  claim 1 , wherein in the connecting conduit injecting means are present for injecting a liquid or gaseous cooling medium into the synthesis gas.  
     
     
         7 . The system according to  claim 6 , wherein the injecting means are injecting means for injecting a liquid cooling medium in the form of a mist of water droplets.  
     
     
         8 . The system according to  claim 1 , wherein the wall of the combustion chamber and the wall of the connecting conduit are provided with cooling means.  
     
     
         9 . The system according to  claim 8 , wherein the cooling means is an arrangement of water-cooled tubes, preferably in the form of a membrane wall.  
     
     
         10 . The system according to  claim 1 , wherein the gasification chamber is provided with one or more pairs of partial oxidation burners, wherein said burners are provided with supply means for a solid carbonaceous feed and supply means for an oxygen containing gas.  
     
     
         11 . A process of preparing a mixture comprising carbon monoxide and hydrogen by partial oxidation of a solid carbonaceous feed, the process comprising: 
 partially oxidizing a solid carbonaceous feed with an oxygen comprising gas in a gasification chamber of a gasification reactor, to form an upwardly moving gas mixture having a temperature of between 1200 and 1800° C. and a pressure of between 20 and 100 bar;    cooling said gas mixture in a connecting conduit to a temperature of between 500 and 900° C. by injecting a gaseous or liquid cooling medium; and    subsequently further cooling the gas mixture in a synthesis gas cooling vessel to below 500° C. by contacting the gas with liquid water;    wherein the gasification chamber is defined by a gasifier wall, a lower open part of which gasifier wall being in fluid communication with a slag bath and an open upper end of which gasifier wall being in fluid communication with the synthesis gas cooling vessel via the connecting conduit.    
     
     
         12 . The process according to  claim 11 , wherein said cooling in the connecting tube and/or in the synthesis gas cooling vessel is performed by injecting a mist of water droplets into the gas flow.  
     
     
         13 . The process according to  claim 12 , wherein the injected water mist has a temperature of at most 50° C. below the bubble point of water at the pressure of the hot synthesis gas.  
     
     
         14 . The process according to  claim 12 , wherein the mist comprises droplets having a diameter of from 50 to 200 μm.  
     
     
         15 . The process according to  claim 12 , wherein the mist is injected at a velocity of between 30-100 m/s.  
     
     
         16 . The process according to  claim 15 , wherein the mist is injected at a velocity of between 40-60 m/s.  
     
     
         17 . The process according to  claim 12 , wherein the mist is injected using an atomizing gas with an injection pressure between 5 and 20 bar above the pressure of the raw synthesis gas.  
     
     
         18 . The process according to  claim 12 , wherein the mist is injected from a wall of the connecting conduit or the cooling vessel, in the direction of the flow of hot synthesis gas, under an angle of between 30-60° with respect to a plane perpendicular to the longitudinal axis of the connecting tube or the cooling vessel.  
     
     
         19 . The process according to  claim 11 , wherein a downwardly moving slag stream is formed during the partial oxidizing.  
     
     
         20 . The process according to  claim 11 , wherein the gasification reactor further comprises: 
 a pressure shell for maintaining the pressure higher than atmospheric pressure, wherein the slag bath is located in a lower part of the pressure shell;    and wherein the synthesis gas cooling vessel comprises:    an inlet for hot synthesis gas, an outlet for cooled synthesis gas and means to, in use, directly contact liquid water with the hot synthesis gas as formed in the gasification reactor.    
     
     
         21 . The process according to  claim 20 , wherein the gasifier wall is arranged inside the pressure shell defining the gasification chamber wherein during operation the synthesis gas is formed.