Systems and Methods for Increasing Carbon Dioxide in Gasification

Abstract

Systems and methods for processing carbonaceous material are provided. In one or more embodiments, a carbonaceous material and water can be mixed to provide a slurried mixture. The water mixed with the carbonaceous material can be at least 90% liquid phase. At least a portion of the slurried mixture can be gasified in the presence of a combustion gas to provide carbonaceous solids and a syngas comprising hydrogen, carbon monoxide, and carbon dioxide. The syngas can be at a temperature of from about 400° C. to about 1,650° C. At least a portion of the carbonaceous solids can be selectively separated from the syngas to provide a syngas product and carbonaceous solids. At least a portion of the separated carbonaceous solids can be combusted in the presence of an oxidant to provide at least a portion of the combustion gas.

1 ) A method for processing a carbonaceous material comprising:
 mixing a carbonaceous material and water to provide a slurried mixture, wherein the water is at least 90% liquid phase;   gasifying at least a portion of the slurried mixture in the presence of a combustion gas to provide carbonaceous solids and a syngas comprising hydrogen, carbon monoxide, and carbon dioxide, wherein the syngas is at a temperature of from about 400° C. to about 1,650° C.;   selectively separating at least a portion of the carbonaceous solids from the syngas to provide a syngas product and carbonaceous solids; and   combusting at least a portion of the separated carbonaceous solids in the presence of an oxidant to provide at least a portion of the combustion gas.   
   
   
       2 ) The method of  claim 1 , further comprising converting at least a portion of the carbon monoxide in the syngas product to carbon dioxide. 
   
   
       3 ) The method of  claim 1 , further comprising separating at least a portion of the carbon dioxide from the syngas product, and storing the separated carbon dioxide in a geological formation, a body of water, or both. 
   
   
       4 ) The method of  claim 3 , further comprising converting at least a portion of the carbon monoxide in the syngas product to carbon dioxide prior to separating at least a portion of the carbon dioxide from the syngas. 
   
   
       5 ) The method of  claim 1 , further comprising separating at least a portion of the carbon dioxide from the syngas product, and converting at least a portion of the separated carbon dioxide to a carbonate, a carbohydrate, or both. 
   
   
       6 ) The method of  claim 5 , further comprising converting at least a portion of the carbon monoxide in the syngas product to carbon dioxide prior to separating at least a portion of the carbon dioxide from the syngas. 
   
   
       7 ) The method of  claim 1 , further comprising directly or indirectly transferring heat from the syngas product to water, steam, or both to provide a cooled syngas product and a steam product. 
   
   
       8 ) The method of  claim 1 , wherein the water concentration of the slurried mixture ranges from about 20% wt to about 70% wt. 
   
   
       9 ) The method of  claim 1 , wherein the oxidant comprises air and the syngas comprises less than 20% mol carbon monoxide and at least 8% mol carbon dioxide. 
   
   
       10 ) The method of  claim 1 , wherein the oxidant is essentially nitrogen-free and the syngas comprises less than 40% mol carbon monoxide and at least 16% mol carbon dioxide. 
   
   
       11 ) The method of  claim 1 , wherein the amount of oxidant present is from about 1% to about 60% of the stoichiometric oxygen required to oxidize the total amount of carbonaceous solids. 
   
   
       12 ) A method for processing a carbonaceous material comprising:
 combining a carbonaceous material and water in a mixing zone to provide a slurried mixture, wherein the water is at least 90% liquid phase;   gasifying a portion of the slurried mixture in the presence of a combustion gas in a gasification zone to provide carbonaceous solids and a syngas comprising hydrogen, carbon monoxide, and carbon dioxide, wherein the syngas has a temperature of from about 400° C. to about 1,650° C.;   selectively separating at least a portion of the carbonaceous solids from the syngas in a separation zone to provide a syngas product and carbonaceous solids; and   combusting at least a portion of the carbonaceous solids in the presence of an oxidant in a combustion zone to provide at least a portion of the combustion gas.   
   
   
       13 ) The method of  claim 12 , further comprising separating at least a portion of the carbon dioxide from the syngas product, and storing the removed carbon dioxide in a geological formation, a body of water, as a carbonate compound, or any combination thereof. 
   
   
       14 ) The method of  claim 13 , further comprising converting at least a portion of the carbon monoxide in the syngas product to carbon dioxide prior to separating the carbon dioxide. 
   
   
       15 ) The method of  claim 12 , wherein the water concentration of the slurried mixture ranges from about 20% wt to about 70% wt. 
   
   
       16 ) The method of  claim 12 , wherein the oxidant comprises air and the syngas comprises less than 20% mol carbon monoxide and at least 8% mol carbon dioxide. 
   
   
       17 ) The method of  claim 12 , wherein the oxidant is essentially nitrogen-free and the syngas comprises less than 40% mol carbon monoxide and at least 16% mol carbon dioxide. 
   
   
       18 ) The method of  claim 12 , further comprising directly or indirectly transferring heat from the syngas product to water, steam, or both to provide a cooled syngas product and a steam product. 
   
   
       19 ) A system for processing a carbonaceous material comprising:
 a gasification zone adapted to gasify a carbonaceous material and water mixture in the presence of a combustion gas to provide carbonaceous solids and a syngas comprising hydrogen, carbon monoxide, and carbon dioxide, wherein the water is at least 90% liquid phase;   a separator in fluid communication with the gasification zone adapted to separate at least a portion of the carbonaceous solids from the syngas; and   an oxidation zone in fluid communication with the gasification zone adapted to combust at least a portion of the separated carbonaceous solids to provide at least a portion of the combustion gas.   
   
   
       20 ) The system of  claim 19 , further comprising a separator adapted to separate at least a portion of the carbon dioxide from the syngas to provide a syngas product comprising less than about 1% mol carbon dioxide, wherein the separated carbon dioxide is suitable for storage in a geological formation, a body of water, as a carbonate compound, or any combination thereof.