Methods and Systems for Gasifying a Process Stream

Abstract

Methods and systems for gasifying process streams are described. In some embodiments, a method for gasifying a process stream includes gasifying the process stream in a first chamber to generate one or more product gases, transporting at least a portion of the one or more product gases to a second chamber, combusting at least a portion of the one or more product gases in the presence of one or more catalysts in the second chamber to generate a heat energy, and indirectly providing the heat energy from the second chamber to the first chamber as a primary heat source to drive gasification of the process stream.

1 . A method for gasifying a process stream, the method comprising:
 providing a process stream including a fuel source;   applying a primary heat source to a first chamber containing the process stream;   gasifying the process stream in the first chamber so as to produce a gasified process stream including one or more product gases;   conducting at least a portion of the one or more product gases to a second chamber;   combusting the at least a portion of the one or more product gases in the presence of one or more catalysts in the second chamber to generate a heat energy; and   conducting the heat energy from the second chamber to the first chamber so as to provide the primary heat source.   
   
   
       2 . A method according to  claim 1 , wherein the one or more product gases include at least one of hydrogen, carbon monoxide, and combinations thereof. 
   
   
       3 . A method according to  claim 1 , further comprising:
 before gasifying the fuel source, mixing an amount of water with the process stream.   
   
   
       4 . A method according to  claim 3 , wherein the water to fuel source molar ratio of the amount of water ranges from about 0.7 to about 1.0. 
   
   
       5 . A method according to  claim 2 , wherein the one or more product gases include hydrogen, and the method further comprises:
 separating substantially all of the hydrogen from the process stream; and   generating a consumable energy with at least a portion of the hydrogen.   
   
   
       6 . A method according to  claim 3 , further comprising:
 separating substantially all of the water from the process stream; and   prior to gasifying, mixing at least a portion of the water with the process stream.   
   
   
       7 . A method according to  claim 2 , further comprising:
 dividing the process stream, which includes an amount of carbon monoxide, into first and second process streams each of which includes a portion of the carbon monoxide from the process stream before it is divided; and   generating a consumable energy with at least a portion of the carbon monoxide contained in at least one of the first and second process streams.   
   
   
       8 . A method according to  claim 7 , further comprising:
 mixing oxygen with at least one of the first and second process streams to prepare the at least one of the first and second process streams for combustion.   
   
   
       9 . A method according to  claim 7 , wherein the portion of the carbon monoxide in the second process stream is from about 20 to about 60 percent by weight of the carbon monoxide contained in the process stream before it is divided. 
   
   
       10 . A method according to  claim 9 , wherein the carbon monoxide in the second process stream is from about 30 to about 50 percent by weight of the carbon monoxide contained in the process stream before it is divided. 
   
   
       11 . A method according to  claim 1 , further comprising:
 generating carbon dioxide while combusting at least a portion of the one or more product gases; and   gasifying a portion of the carbon dioxide with the process stream.   
   
   
       12 . A method according to  claim 11 , wherein the portion of the carbon dioxide gasified is from about 0 to about 50 percent by weight of the carbon dioxide generated while combusting at least a portion of the one or more product gases in the presence of the one or more catalysts. 
   
   
       13 . A method according to  claim 1 , wherein gasifying the process stream is driven substantially from the heat energy generated from combusting at least a portion of the one or more product gases in the presence of one or more catalysts. 
   
   
       14 . A method according to  claim 1 , wherein the fuel source is at least one of coal, a biomass, and combinations thereof. 
   
   
       15 . A method according to  claim 1 , wherein gasifying the fuel source includes a maximum temperature of about 850 degrees Celsius. 
   
   
       16 . A method according to  claim 1 , wherein combusting the one or more product gases includes a maximum temperature of about 1300 degrees Celsius. 
   
   
       17 . A system for gasifying a process stream, the system comprising:
 a first chamber for gasifying the process stream to produce a gasified process stream including at least one of one or more product gases, water, and particulates, the gasification chamber including sidewalls;   a primary heat source for heating the first chamber; and   a second chamber for combusting the process stream, said second chamber in fluid communication with the first chamber and at least a portion of the process stream, the second chamber including one or more portions that are in thermal communication with respective ones of the sidewalls of the gasification chamber, the second chamber including interior surfaces having a coating formed from one or more catalysts, the second chamber being configured to combust at least a portion of the process stream to generate a heat energy that serves as the primary heat source and is provided to the first chamber via the one or more portions that thermally communicate with the first chamber.   
   
   
       18 . A system according to  claim 17 , wherein the one or more product gases include at least one of hydrogen, carbon monoxide, and combinations thereof. 
   
   
       19 . A system according to  claim 17 , further comprising:
 an oxygen supply in fluid communication with the second chamber.   
   
   
       20 . A system according to  claim 18 , further comprising:
 a separator for separating the hydrogen from the process stream.   
   
   
       21 . A system according to  claim 17 , further comprising:
 a separator for separating water from the process stream.   
   
   
       22 . A system according to  claim 18 , further comprising:
 at least one of a divider for dividing the process stream or a separator for separating carbon monoxide from the process stream.   
   
   
       23 . A system according to  claim 22 , further comprising:
 at least one of a fuel cell, a gas turbine engine, or an internal combustion engine capable of generating a consumable energy in the form of electricity from at least a portion of the carbon monoxide.   
   
   
       24 . A system according to  claim 17 , wherein the one or more catalysts include one or more of precious group metals, hexaaluminates, spinels, zeolites, base metal formulations, and combinations thereof. 
   
   
       25 . A system according to  claim 17 , wherein the first chamber and the second chamber are modular. 
   
   
       26 . A system according to  claim 17 , wherein the process stream includes a fuel source including at least one of coal and a biomass. 
   
   
       27 . A catalytic reaction gasifier for gasifying a process stream, the gasifier comprising:
 a housing including one or more inlets and one or more outlets;   a combustion chamber defined within the housing, the combustion chamber including a plurality of interior surfaces;   one or more catalysts positioned within the combustion chamber; and   a gasification chamber separate from but positioned so as to be in thermal communication with the combustion chamber, the gasification chamber including a first end and a second end, the first end being operably connected with the one or more inlets for receiving the process stream and the second end being operably connected with the one or more outlets.   
   
   
       28 . A gasifier according to  claim 27 , wherein the gasification chamber includes at least one tube that extends through the combustion chamber thereby allowing the gasification chamber to thermally communicate with the combustion chamber. 
   
   
       29 . A gasifier according to  claim 27 , wherein the combustion chamber includes at least one tube that extends through the gasification chamber thereby allowing the gasification chamber to thermally communicate with the combustion chamber. 
   
   
       30 . A gasifier according to  claim 27 , wherein the process stream includes a fuel source including at least one of coal and a biomass. 
   
   
       31 . A gasifier according to  claim 27 , wherein the combustion chamber and the gasification chamber are configured so that a portion of heat energy generated in the combustion chamber heats the gasification chamber thereby gasifying the process stream into a process stream containing hydrogen. 
   
   
       32 . A gasifier according to  claim 31 , further comprising:
 at least one separator for separating hydrogen, particulates, water, or carbon monoxide from the process stream.   
   
   
       33 . A gasifier according to  claim 31 , wherein the one or more outlets include a first outlet for exhausting gases from the combustion chamber, a second outlet for exhausting solid wastes from the gasification chamber, a third outlet for exhausting gaseous wastes from the gasification chamber, and a fourth outlet for exhausting hydrogen from the gasification chamber. 
   
   
       34 . A gasifier according to  claim 27 , wherein the one or more inlets include a first inlet for receiving the fuel source and a second inlet for receiving carbon monoxide, oxygen, or a combination thereof. 
   
   
       35 . A gasifier according to  claim 27 , wherein the one or more catalysts are selected from the group consisting of precious group metals, hexaaluminates, spinels, zeolites, base metal formulations, and combinations thereof.