Mitigation of harmful combustion emissions using sorbent containing engineered fuel feedstocks

Abstract

The invention relates to the use of engineered fuel feedstocks to control the emission of sulfur-based, chlorine-based, nitrogen-based, or mercury-based pollutants, such as SO2, SO3, H2SO4, NO, NO2, HCl, and Hg that are generated during the combustion of fossil fuels, such as coal. Disclosed are novel engineered fuel feedstocks, feedstocks produced by the described processes, methods of making the fuel feedstocks, methods of producing energy from the fuel feedstocks, and methods of generating electricity from the fuel feedstocks.

1 . An engineered fuel feedstock having a volatile portion, comprising at least two sorbents and MSW, wherein
 at least one sorbent is a sodium-based sorbent,   at least one sorbent is a calcium-based sorbent, and   the MSW comprises about 5% (w/w) to about 50% (w/w) plastic and about 50% (w/w) to about 95% (w/w) fiber and contains substantially no glass, metals, grit, and noncombustible waste.   
     
     
         2 . The engineered fuel feedstock of  claim 1 , wherein
 the volatile portion of the engineered fuel feedstock has
 a carbon content of about 25% (w/w) to about 59% (w/w) 
 a hydrogen content of about 3% (w/w) to about 8% (w/w) 
 an oxygen content of about 9% (w/w) to about 44% (w/w) 
   wherein
 the H/C ratio is from about 0.07 to about 0.21, and 
 the O/C ratio is from about 0.19 to about 1.52. 
   
     
     
         3 . The engineered fuel feedstock of  claim 2 , wherein
 the volatile portion of the engineered fuel feedstock has
 a carbon content of about 25% (w/w) to about 50% (w/w) 
 a hydrogen content of about 3.0% (w/w) to about 5.3% (w/w) 
 an oxygen content of about 15% (w/w) to about 39% (w/w) 
   wherein
 the H/C ratio is from about 0.07 to about 0.19, and 
 the O/C ratio is from about 0.36 to about 1.27. 
   
     
     
         4 - 6 . (canceled) 
     
     
         7 . The engineered fuel feedstock of  claim 2 , wherein the carbon, hydrogen, and/or oxygen contents were determined by ASTM test methods D5373, D3176, D6373, or a combination thereof. 
     
     
         8 . The engineered fuel feedstock of  claim 1 , wherein the sodium-based sorbent is about 19% (w/w) to about 30% of the total weight of the engineered fuel feedstock. 
     
     
         9 . The engineered fuel feedstock of  claim 1 , wherein the sodium-based sorbent is selected from the group consisting of trisodium hydrogendicarbonate dihydrate (Trona), sodium sesquicarbonate, sodium bicarbonate, sodium carbonate, and combinations thereof. 
     
     
         10 . (canceled) 
     
     
         11 . The engineered fuel feedstock of  claim 10 , wherein the sodium bicarbonate comprises about 19% (w/w) to about 30% (w/w) of the total weight of the engineered fuel feedstock feed stock. 
     
     
         12 . The engineered fuel feedstock of  claim 1 , wherein the calcium-based sorbent is about 5% (w/w) to about 12% w/w of the total weight of the engineered fuel feedstock. 
     
     
         13 - 21 . (canceled) 
     
     
         22 . The engineered fuel feedstock of  claim 1 , wherein the MSW comprises about 10% (w/w) to about 30% (w/w) plastic and about 70% (w/w) to about 90% (w/w) fiber 
     
     
         23 . The engineered fuel feedstock of  claim 22 , wherein the MSW comprises about 20% (w/w) plastic and about 80% (w/w) fiber. 
     
     
         24 . The engineered fuel feedstock of  claim 1 , wherein the plastic comprises soft plastic. 
     
     
         25 - 65 . (canceled) 
     
     
         66 . A method of making an engineered fuel feedstock, comprising processing plastic and sodium-based and calcium-based sorbents with at least about 50% of the plastic to form a plastic-sorbent pellet which is then processed with fiber and any remaining plastic to form fiber-plastic-sorbent-pellets. 
     
     
         67 . The method of  claim 66 , wherein the sodium-based sorbent is selected from the group consisting of trisodium hydrogendicarbonate dihydrate (Trona), sodium sesquicarbonate, sodium bicarbonate, sodium carbonate, and combinations thereof. 
     
     
         68 . The method of  claim 67 , wherein the sodium-based sorbent is sodium bicarbonate. 
     
     
         69 . The method of  claim 66 , wherein the calcium-based sorbent is selected from the group consisting of calcium carbonate, calcium oxide, calcium hydroxide, calcium magnesium acetate (CaMg 2 (CH 3 COO) 6 ), calcium bromide, dolomite (CaCO 3 .MgO), and combinations thereof. 
     
     
         70 . The method of  claim 69 , wherein the calcium-based sorbent is calcium hydroxide. 
     
     
         71 . The method of  claim 66 , further comprising a sorbent for mercury reduction. 
     
     
         72 . The method of  claim 71 , wherein the additional sorbent for mercury reduction is calcium bromide. 
     
     
         73 . The method of  claim 66 , further comprising a sorbent for NO x  reduction. 
     
     
         74 . The method of  claim 73 , wherein the additional sorbent for NO x  reduction is urea.