Process for cogasifying and cofiring engineered fuel with coal

Abstract

Described is an integrated process of cogasifying an engineered fuel, formulated to be suitable for working under reducing environment, with coal and cofiring another engineered fuel, formulated to be suitable for working under oxidizing environment, with coal to produce electric power.

1 . An integrated method of a combustion system, comprising:
 introducing a first engineered fuel and a first fossil fuel into a gasifier;   cogasifying the first engineered fuel and the first fossil fuel to produce syngas;   introducing a second engineered fuel, a second fossil fuel and the produced syngas into a combustion reactor; and   cofiring the second engineered fuel, the second fossil fuel, and the produced syngas.   
     
     
         2 . The method of  claim 1 , wherein the first engineered fuel is different from the second engineered fuel. 
     
     
         3 . The method of  claim 2 , wherein the first engineered fuel is optimized for cogasifying in a reducing environment, and wherein the second engineered fuel is optimized for cofiring in an oxidizing environment. 
     
     
         4 . The method of  claim 3 , wherein the combustor is a boiler, wherein cofiring comprises:
 combusting the second engineered fuel and the second fossil fuel in a combustion zone of the boiler, and   combusting the syngas in a reburn zone of the boiler.   
     
     
         5 . The method of  claim 1 , wherein the cofiring step comprises one of direct cofiring and indirect cofiring. 
     
     
         6 . The method of  claim 1 , wherein at least one of the first engineered fuel and the second engineered fuel comprises one or more sorbents. 
     
     
         7 . The method of  claim 6 , wherein the one or more sorbents are selected from the group consisting of sodium sesquicarbonate (Trona), sodium bicarbonate, sodium carbonate, zinc ferrite, zinc copper ferrite, zinc titanate, copper ferrite aluminate, copper aluminate, copper manganese oxide, nickel supported on alumina, zinc oxide, iron oxide, copper, copper (I) oxide, copper (II) oxide, limestone, lime, Fe, FeO, Fe 2 O 3 , Fe 3 O 4 , iron filings, CaCO 3 , Ca(OH) 2 , CaCO 3 .MgO, CaMg 2 (CH 3 COO) 6 , silica, alumina, china clay, kaolinite, bauxite, emathlite, attapulgite, coal ash, egg shells, Ca-montmorillonite, calcium magnesium acetate, calcium acetate, calcium formate, calcium benzoate, calcium propionate, and magnesium acetate, and mixtures thereof. 
     
     
         8 . The method of  claim 1 , wherein the fossil fuel comprises one or more variety of coal. 
     
     
         9 . The method of  claim 8 , wherein the one or more variety of coal is selected from the group consisting of: anthracite, lignite, bituminous coal, and mixtures thereof. 
     
     
         10 - 35 . (canceled) 
     
     
         36 . An integrated method of a combustion system, comprising:
 introducing a first engineered fuel and a first fossil fuel into a cofiring unit;   cofiring the first engineered fuel and the first fossil fuel to produce syngas;   introducing a second engineered fuel, a second fossil fuel and the produced syngas into a combustion reactor; and   cofiring the second engineered fuel, the second fossil fuel, and the produced syngas.   
     
     
         37 . The method of  claim 36 , wherein the cofiring unit is selected from: a gasifier, a combustor, and a boiler. 
     
     
         38 . The method of  claim 37 , wherein the cofiring unit is a combustor or a boiler, said combustor or boiler having a zone operated in a reducing environment. 
     
     
         39 . The method of  claim 36 , wherein the syngas is completely or incompletely combusted. 
     
     
         40 . The method of  claim 36 , wherein the first engineered fuel is different from the second engineered fuel. 
     
     
         41 . The method of  claim 40 , wherein the first engineered fuel is optimized for burning in a reducing environment, and wherein the second engineered fuel is optimized for burning in an oxidizing environment. 
     
     
         42 . The method of  claim 41 , wherein the combustion reactor is a boiler, wherein cofiring the second engineered fuel, the second fossil fuel, and the produced syngas comprises:
 combusting the second engineered fuel and the second fossil fuel in a combustion zone of the boiler, and   combusting the syngas in a reburn zone of the boiler.   
     
     
         43 . The method of  claim 36 , wherein cofiring comprises at least one of direct cofiring and indirect cofiring. 
     
     
         44 . The method of  claim 36 , wherein at least one of the first engineered fuel and the second engineered fuel comprises one or more sorbents. 
     
     
         45 . The method of  claim 44 , wherein the one or more sorbents are selected from the group consisting of sodium sesquicarbonate (Trona), sodium bicarbonate, sodium carbonate, zinc ferrite, zinc copper ferrite, zinc titanate, copper ferrite aluminate, copper aluminate, copper manganese oxide, nickel supported on alumina, zinc oxide, iron oxide, copper, copper (I) oxide, copper (II) oxide, limestone, lime, Fe, FeO, FeO 3 , Fe 3 O 4 , iron filings, CaCO 3 , Ca(OH) 2 , CaCO 3 .MgO, CaMg 2 (CH 3 COO) 6 , silica, alumina, china clay, kaolinite, bauxite, emathlite, attapulgite, coal ash, egg shells, Ca-montmorillonite, calcium magnesium acetate, calcium acetate, calcium formate, calcium benzoate, calcium propionate, and magnesium acetate, and mixtures thereof. 
     
     
         46 . The method of  claim 36 , wherein the first fossil fuel or second fossil fuel comprises one or more variety of coal. 
     
     
         47 . The method of  claim 36 , wherein the one or more variety of coal is selected from the group consisting of: anthracite, lignite, bituminous coal, and mixtures thereof.