Method for producing fuel gas

Abstract

A method for producing a synthesis gas from a widely varying feedstock of waste and natural fuels including providing a reaction chamber having a bottom coupled to an induction furnace, introducing a carbonaceous fuel into a molten metal contained within the reaction chamber, continuously or intermittently supplying heat and molten metal to the reaction chamber from the induction furnace and collecting a fuel gas generated within the reaction chamber.

1 . A method of gasifying a carbonaceous fuel comprising,
 providing a reaction chamber coupled to an induction furnace,   introducing the carbonaceous fuel into a molten metal contained within the reaction chamber, and   collecting a fuel gas generated within the reaction chamber.   
     
     
         2 . The method according to  claim 1  wherein the induction furnace is a coreless induction furnace. 
     
     
         3 . The method according to  claim 1  wherein the reaction chamber is mounted on top of the induction furnace. 
     
     
         4 . The method according to  claim 1  further comprising circulating the molten metal between the reaction chamber and the induction furnace though an opening in a bottom of the reaction chamber. 
     
     
         5 . The method according to  claim 1  further comprising heating the molten metal by induction heating. 
     
     
         6 . The method according to  claim 1  wherein the carbonaceous fuel is selected from the group consisting of municipal solid waste, medical waste, household hazardous waste, spent tires, biomass, bio-solids, industrial wastes, various grades of coal, coke and combinations thereof 
     
     
         7 . The method according to  claim 1  wherein the carbonaceous fuel is introduced into a froth zone and into an off take zone, each of the froth zone and the take- off zone being within the reaction chamber and directly above the molten metal. 
     
     
         8 . The method according to  claim 1  wherein the method is a continuous process. 
     
     
         9 . A method of producing a fuel gas comprising,
 introducing a carbonaceous fuel into a molten metal bath supported above an induction furnace,   heating the molten metal bath using the induction furnace,   generating the fuel gas, and   collecting the fuel gas.   
     
     
         10 . The method according to  claim 9  wherein the molten metal bath is contained within a reaction chamber mounted on top of the induction furnace, the reaction chamber having an opening through a bottom thereof that is in fluid communication with an interior of the induction furnace. 
     
     
         11 . The method according to  claim 10  wherein the bottom has an inside working circumference that is at least three times greater than an inside circumference of the interior of the induction furnace. 
     
     
         12 . The method according to  claim 10  wherein a coreless induction furnace is mounted to the bottom, the coreless induction furnace having an inside that is in fluid communication with a second opening through the bottom of the reaction chamber. 
     
     
         13 . The method according to  claim 9  further comprising stirring the molten metal bath using the induction furnace. 
     
     
         14 . The method according to  claim 9  further comprising obtaining a temperature of the molten metal bath, determining whether it is desired to add heat to the molten metal bath based upon the temperature of the molten metal bath, and adding heat to the molten metal bath using the induction furnace in a continuous process as needed. 
     
     
         15 . The method according to  claim 14  further comprising controlling a height of a froth derived from the molten metal bath by introducing a gas selected from the group consisting of combustible light gases, oxygen, carbon dioxide, steam and combinations thereof into an off take zone located above the molten metal bath. 
     
     
         16 . The method according to  claim 9  wherein, when the carbonaceous fuel is a low heat value fuel, a temperature of the molten metal bath is maintained within a desired range by adding heat to the molten metal bath. 
     
     
         17 . A method of producing a fuel gas comprising,
 providing a gasifier including a reaction chamber, a molten metal and an induction furnace,   induction heating the molten metal,   induction stirring the molten metal,   injecting a carbonaceous fuel into the molten metal generating the fuel gas, and collecting the fuel gas.   
     
     
         18 . The method according to  claim 17  wherein the induction furnace is a coreless induction furnace. 
     
     
         19 . The method according to  claim 18  wherein the induction furnace is integrally coupled to a bottom of the reaction chamber and the bottom includes an opening through which the molten metal is circulated between the induction furnace and the reaction chamber. 
     
     
         20 . The method according to  claim 19  wherein the bottom has an inside working circumference that is at least three times greater than a circumference of the opening. 
     
     
         21 . The method according to  claim 19  wherein a second induction furnace and a third induction furnace are coupled to the bottom of the reaction chamber, each of the induction furnace, the second induction furnace and the third induction furnace, being connected to a respective phase of a three phase industrial power supply. 
     
     
         22 . The method according to  claim 17  wherein the reaction chamber has a volume that is at least fifteen times greater than an inside working volume of the induction furnace. 
     
     
         23 . The method according to  claim 17  wherein the carbonaceous fuel and reaction gases are injected into a volume of the molten metal that is isolated from induction furnace. 
     
     
         24 . The method according to  claim 17  further comprising obtaining a temperature of the molten metal, determining whether the molten metal is at a desired temperature, and adding heat to the molten metal using the induction furnace to achieve the desired temperature. 
     
     
         25 . The method according to  claim 19  wherein the carbonaceous fuel and one or more reaction gases are introduced into a reaction area contained within the reaction chamber above the molten metal , the reaction area being comprised of contiguous gasification zones, starting from the bottom and moving upward, designated as molten metal gasification zone, a slag gasification zone, a froth gasification zone and an off take gasification zones. 
     
     
         26 . The method according to  claim 1  further comprising injecting carbon in the carbonaceous fuel into the reaction chamber at a first rate and oxidizing carbon in the reaction chamber to carbon monoxide at a second rate wherein the first rate and the second rate are substantially the same. 
     
     
         27 . The method according to  claim 1  further comprising injecting carbon in the carbonaceous fuel into the reaction chamber at a first rate and oxidizing the molten metal at a second rate wherein the first rate and the second rate are substantially the same. 
     
     
         28 . The method according to  claim 1  further comprising oxidizing the molten metal to metal oxide at a first rate and reducing the metal oxide with carbon in the carbonaceous fuel at a second rate wherein the first rate and the second rate are substantially the same. 
     
     
         29 . The method according to  claim 9  further comprising injecting carbon in the carbonaceous fuel into the reaction chamber at a first rate and oxidizing the carbon in the reaction chamber to carbon monoxide at a second rate wherein the first rate and the second rate are substantially the same. 
     
     
         30 . The method according to  claim 9  further comprising injecting carbon in the carbonaceous fuel into the reaction chamber at a first rate and oxidizing the molten metal at a second rate wherein the first rate and the second rate are substantially the same. 
     
     
         31 . The method according to  claim 9  further comprising oxidizing the molten metal to metal oxide at a first rate and reducing the metal oxide with carbon in the carbonaceous fuel at a second rate wherein the first rate and the second rate are substantially the same. 
     
     
         32 . The method according to  claim 17  further comprising injecting carbon in the carbonaceous fuel into the reaction chamber at a first rate and oxidizing the carbon in the reaction chamber to carbon monoxide at a second rate wherein the first rate and the second rate are substantially the same. 
     
     
         33 . The method according to  claim 17  further comprising injecting carbon in the carbonaceous fuel into the reaction chamber at a first rate and oxidizing the molten metal at a second rate wherein the first rate and the second rate are substantially the same. 
     
     
         34 . The method according to  claim 17  further comprising oxidizing the molten metal to metal oxide at a first rate and reducing the metal oxide with carbon in the carbonaceous fuel at a second rate wherein the first rate and the second rate are substantially the same. 
     
     
         35 . A method for producing a fuel gas comprising,
 providing a reaction chamber containing a molten metal,   oxidizing the molten metal to metal oxide at a first rate,   injecting carbon into the reaction chamber at a second rate,   reducing the metal oxide at a third rate, and   oxidizing the carbon to carbon monoxide at a fourth rate.   
     
     
         36 . The method according to  claim 35  wherein the first rate, the second rate, the third rate and the fourth rate are substantially the same. 
     
     
         37 . The method according to  claim 35  wherein the first rate and the third rate are substantially the same. 
     
     
         38 . The method according to  claim 35  wherein the second rate and the fourth rate are substantially the same. 
     
     
         39 . The method according to  claim 35  wherein the molten metal is iron and the metal oxide is iron oxide. 
     
     
         40 . The method according to  claim 35  wherein the carbon is injected in the form of a carbonaceous fuel selected from the group consisting of municipal solid waste, medical waste, household hazardous waste, spent tires, biomass, bio-solids, industrial wastes, various grades of coal, coke and combinations thereof.