Process and apparatus for the production of synthesis gas

Abstract

Reactive diluent fluid is introduced into a stream of synthesis gas (or “syngas”) produced in a heat-generating unit such as a partial oxidation (“POX”) reactor to cool the syngas and form a mixture of cooled syngas and reactive diluent fluid. Carbon dioxide and/or carbon components and/or hydrogen in the mixture of cooled syngas and reactive diluent fluid is reacted with at least a portion of the reactive diluent fluid in the mixture to produce carbon monoxide-enriched syngas which may be fed into a secondary reformer unit such as an enhanced heat transfer reformer in a heat exchange reformer process. An advantage of the invention is that problems with the mechanical integrity of the secondary unit arising from the high temperature of the syngas from the heat-generating unit are avoided.

1 . A process for the production of synthesis gas (“syngas”) comprising carbon monoxide and molecular hydrogen, said process comprising; 
 exothermically reacting hydrocarbon-containing fuel with an oxidant gas comprising molecular oxygen in a first reactor to produce an exothermically-generated syngas product;  
 combining a stream of reactive diluent fluid with a stream of said exothermically-generated syngas product to produce a reactive mixture; and  
 reacting said mixture in a second reactor to produce a reacted syngas product.  
 
     
     
         2 . The process according to  claim 1 , wherein the oxidant gas consists of molecular oxygen.  
     
     
         3 . The process according to  claim 1 , wherein the hydrocarbon fuel is reacted with the oxidant gas in the presence of water.  
     
     
         4 . The process according to  claim 1  wherein the reactive mixture comprises carbon dioxide, at least a portion of which is reacted together with at least a portion of the molecular hydrogen in said mixture over a catalyst in a reverse water gas shift reaction zone to produce a carbon monoxide-enriched syngas product.  
     
     
         5 . The process according to  claim 1  wherein the reactive mixture comprises solid carbon particles, at least a portion of which is gasified by reaction with at least one other component of the mixture in a gasification zone to produce a solid carbon-depleted syngas product.  
     
     
         6 . The process according to  claim 1  further comprising endothermically reforming hydrocarbon-containing fuel gas with steam over a catalyst in a heat exchange reformer to produce a heat exchange-reformed syngas product, wherein at least a portion of the heat required in the generation of said heat exchange-reformed syngas product is obtained by recovering heat from said reacted syngas product thereby cooling the reacted syngas product.  
     
     
         7 . The process according to  claim 6  wherein said heat exchange-reformed syngas product is combined with said reacted syngas product prior to heat recovery.  
     
     
         8 . The process according to  claim 1  wherein the reactive diluent fluid is a gas thereby cooling the exothermically-generated syngas product via sensible heat exchange.  
     
     
         9 . The process according to  claim 1  wherein the reactive diluent fluid is a liquid thereby cooling the exothermically-generated syngas product via vaporisation and sensible heat exchange.  
     
     
         10 . The process according to  claim 1  wherein the reactive diluent fluid is recovered and recycled from downstream processing of syngas.  
     
     
         11 . The process according to  claim 1  wherein the reactive diluent fluid comprises carbon dioxide.  
     
     
         12 . The process according to  claim 11  wherein the reactive diluent fluid comprises carbon dioxide separated and recycled from downstream syngas.  
     
     
         13 . The process according to  claim 11  wherein the reactive diluent fluid comprises the products of a combustion process.  
     
     
         14 . The process according to  claim 13  wherein the combustion products are selected from the group consisting of combustion furnace flue gases and gas turbine exhaust gas.  
     
     
         15 . The process according to  claim 11  wherein the reactive diluent fluid comprises carbon dioxide imported from an external source.  
     
     
         16 . The process according to  claim 11  wherein the reactive diluent fluid further comprises a component selected from the group consisting of methane and other hydrocarbon(s).  
     
     
         17 . The process according to  claim 1  wherein the reactive diluent fluid comprises molecular hydrogen.  
     
     
         18 . The process according to  claim 1  wherein the reactive diluent fluid comprises water.  
     
     
         19 . The process according to  claim 18  wherein the water is in the form of liquid water.  
     
     
         20 . The process according to  claim 18  wherein at least a portion of the water is in the form of steam.  
     
     
         21 . The process according to  claim 1  wherein the reacted syngas product is used in a downstream conversion process to produce conversion products selected from the group consisting of hydrocarbon liquid fuels, methanol, DME and oxo-alcohols.  
     
     
         22 . A process for the production of syngas comprising carbon monoxide and molecular hydrogen, said process comprising; 
 exothermically reacting hydrocarbon-containing fuel with an oxidant gas comprising molecular oxygen in a first reactor to produce an exothermically-generated syngas product;    cooling an effluent stream of said exothermically-generated syngas product by combining reactive diluent fluid with said stream to produce a mixture comprising cooled exothermically-generated syngas product and reactive diluent fluid, said mixture further comprising at least one component selected from the group consisting of carbon dioxide and solid carbon particles;    reacting together carbon dioxide in said mixture with molecular hydrogen in said mixture to produce a carbon monoxide-enriched syngas product; and/or    gasifying solid carbon particles in said mixture with at least one other component in said mixture to produce a solid carbon-depleted syngas product.    
     
     
         23 . A process for the production of syngas comprising carbon monoxide and molecular hydrogen, said process comprising: 
 exothermically reacting hydrocarbon-containing fuel gas with an oxidant gas comprising molecular oxygen in a first reactor to produce a first syngas product;    cooling an effluent stream of said first syngas product by combining reactive diluent fluid comprising carbon dioxide with said stream to produce a mixture of cooled first syngas product and reactive diluent fluid;    reacting at least a portion of the carbon dioxide in said mixture with at least a portion of the molecular hydrogen in said mixture over a catalyst in a reverse water gas shift reaction zone to produce a carbon monoxide-enriched syngas product;    endothermically reforming hydrocarbon-containing fuel gas with steam over a catalyst in a heat exchange reformer to produce a second syngas product; and    combining at least a portion of said second syngas product with at least a portion of the carbon monoxide-enriched syngas product to produce a combined syngas product,    wherein at least a portion of the heat generated in the exothermic reaction producing said first syngas product is used to drive the endothermic reforming reaction.    
     
     
         24 . Apparatus for the production of syngas comprising carbon monoxide and molecular hydrogen, said apparatus comprising: 
 a first reactor in which hydrocarbon-containing fuel is reacted exothermically with an oxidant gas comprising molecular oxygen to produce an exothermically-generated syngas product;    conduit means for removing an effluent stream of said exothermically-generated syngas product from the first reactor;    means for combining a stream of reactive diluent fluid with said effluent stream to produce a reactive mixture; and    a second reactor in which said mixture reacts to produce a reacted syngas product.    
     
     
         25 . Apparatus according to  claim 24  wherein the first reactor is selected from the group consisting of a partial oxidation (“POX”) reactor, an autothermal reformer (“ATR”) and a catalytic partial oxidation (“CPO”) reactor.  
     
     
         26 . Apparatus according to  claim 24  wherein the reactive mixture comprises carbon dioxide and the second reactor has a reverse water gas shift reaction zone in which at least a portion of the carbon dioxide and at least portion of the molecular hydrogen in said mixture are reacted together over a catalyst to produce a carbon monoxide-enriched syngas product.  
     
     
         27 . Apparatus according to  claim 24  wherein the reactive mixture comprises solid carbon particles and the second reactor has a gasification reaction zone in which at least a portion of the solid carbon particles is gasified by reaction with at least one other component of the mixture to produce a solid carbon-depleted syngas product.  
     
     
         28 . Apparatus according to  claim 24  further comprising a heat exchange reformer in which hydrocarbon-containing fuel gas is reformed endothermically with steam over a catalyst to produce a heat exchange-reformed syngas product, wherein at least a portion of the heat required in the generation of said heat exchange-reformed syngas product is obtained by recovering heat from said reacted syngas product thereby cooling the reacted syngas product.  
     
     
         29 . Apparatus according to  claim 28  wherein the heat exchange reformer is a shell and tube style reformer in which the endothermic reforming reaction occurs within the tubes and the reacted syngas product is introduced to the shell-side.  
     
     
         30 . Apparatus according to  claim 28  wherein the reformer is an enhanced heat transfer reformer (“EHTR”).  
     
     
         31 . Apparatus for the production of syngas comprising carbon monoxide and molecular hydrogen, said apparatus comprising: 
 a first reactor in which hydrocarbon-containing fuel is reacted exothermically with an oxidant gas comprising molecular oxygen to produce an exothermically-generated syngas product;    conduit means for removing an effluent stream of said exothermically generated syngas product from the first reactor;    means for combining reactive diluent gas comprising carbon dioxide with said effluent stream to produce a mixture comprising cooled first syngas product and reactive diluent gas, said mixture further comprising at least one component selected from the group consisting of carbon dioxide and solid carbon particles;    a reverse water gas shift reaction zone in which carbon dioxide in said mixture is reacted together with molecular hydrogen in said mixture over a catalyst to produce a carbon monoxide-enriched syngas product; and/or    a gasification reaction zone in which solid carbon particles in said mixture are gasified with at least one other component in said mixture to produce a solid carbon-depleted syngas product.    
     
     
         32 . Apparatus for the production of syngas comprising carbon monoxide and molecular hydrogen, said apparatus comprising: 
 a first reactor in which hydrocarbon-containing fuel gas is reacted exothermically with an oxidant gas comprising molecular oxygen to produce a first syngas product;    conduit means for removing an effluent stream of said first syngas product from the first reactor;    means for combining reactive diluent gas comprising carbon dioxide with said effluent stream to produce a mixture of cooled first syngas product and reactive diluent gas;    a reverse water gas shift reaction zone in which at least a portion of the carbon dioxide in said mixture is reacted with at least a portion of the molecular hydrogen in said mixture over a catalyst to produce a carbon monoxide-enriched syngas product; and    a heat exchange reformer in which hydrocarbon-containing fuel gas is reformed endothermically with steam over a catalyst to produce a second syngas product and in which at least a portion of said second syngas product is combined with at least a portion of said carbon monoxide-enriched syngas product to produce a combined syngas product, wherein at least a portion of the heat generated in the exothermic reaction producing said first syngas product is used to drive the endothermic reforming reaction.    
     
     
         33 . Apparatus according to  claim 32  wherein the first reactor is a partial oxidation (“POX”) reactor and the reformer is an EHTR.