Systems and methods for producing engineered fuel feedstocks with reduced chlorine content

Abstract

Systems and methods for producing engineered fuels from municipal solid waste material are described herein. In some embodiments, a method includes combining a first waste stream that includes at least one of hard plastic, soft plastic and mixed plastic with a sorbent and increasing the temperature of the combined first waste stream and sorbent to a temperature of at least about 200° C. The method further includes combining the thermally treated first waste stream and sorbent with a second waste stream that includes fiber, and compressing the combined first waste stream, sorbent, and second waste stream to form a densified engineered fuel feedstock.

1 . A method of producing an engineered fuel feedstock from a processed MSW waste stream, the method comprising:
 combining a first waste stream that includes at least one of hard plastic, soft plastic and mixed plastic with a sorbent;   increasing the temperature of the combined first waste stream and sorbent to a temperature of at least about 200° C.;   combining the thermally treated first waste stream and sorbent with a second waste stream, the second waste stream including fiber; and   compressing the combined first waste stream, sorbent, and second waste stream to form a densified engineered fuel feedstock.   
     
     
         2 . The method of  claim 1 , wherein the temperature of the combined first waste stream and sorbent is increased for at least about 10 minutes. 
     
     
         3 . The method of  claim 2 , wherein the temperature of the combined first waste stream and sorbent is increased to at least about 30 minutes. 
     
     
         4 . The method of  claim 3 , wherein the temperature of the combined first waste stream and sorbent is increased to at least about 350° C. 
     
     
         5 . The method of  claim 1 , wherein the first waste stream consists essentially of hard plastic and soft plastic. 
     
     
         6 . The method of  claim 1 , wherein the second waste stream consists essentially of fiber. 
     
     
         7 . The method of  claim 1 , further comprising:
 processing the engineered fuel feedstock to an average particle size of less than about ¼ inch.   
     
     
         8 . A method of producing an engineered fuel feedstock from processed MSW waste streams, the method comprising:
 heating a first waste stream above a decomposition point to produce a second waste stream and a gas;   extracting the gas from the second waste stream;   reacting the gas to a less reactive state;   combining the second waste stream with a third waste stream in a predetermined ratio to form an engineered fuel feedstock.   
     
     
         9 . The method of  claim 8 , wherein the first waste stream includes chlorinated plastics. 
     
     
         10 . The method of  claim 8 , wherein the third waste stream consists essentially of fiber. 
     
     
         11 . The method of  claim 8 , wherein the first waste stream is heated to a range from about 200° C. to about 350° C. 
     
     
         12 . The method of  claim 8 , wherein the gas includes at least one chlorine, HCl, plasticizers, diluents, and VOC's. 
     
     
         13 . The method of  claim 8 , wherein the chlorine content of the second waste stream is less than about 500 ppm. 
     
     
         14 . The method of  claim 8 , wherein the first waste stream includes a sorbent. 
     
     
         15 . The method of  claim 8 , wherein the first waste stream is about 50% to about 90% by weight of sorbent. 
     
     
         16 . The method of  claim 14 , wherein the sorbent is at least one of sodium sesquicarbonate (Trona), sodium bicarbonate, sodium carbonate, zinc ferrite, zinc copper ferrite, zinc titanate, copper ferrite aluminate, copper aluminate, copper managanese 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, silica, alumina, china clay, kaolinite, bauxite, emathlite, attapulgite, coal ash, egg shells, organic salts (such as calcium magnesium acetate (CMA), calcium acetate (CA), calcium formate (CF), calcium benzoate (CB), calcium propionate (CP) and magnesium acetate (MA)), urea, calcium bromide, sodium bromide, ammonium bromide, hydrogen bromide, ammonium sulfate, lignosulfonate and Ca-montmorillonite. 
     
     
         17 . A method, comprising:
 processing a municipal solid waste stream to remove non-combustible waste;   sorting the processed waste stream based on density into a first material of a first density classification having a bulk density greater than about 15 lb/ft 3 , a second material of a second density classification having a bulk density between about 4 lb/ft 3  and about 15 lb/ft 3 , and a third material of a third density classification having a bulk density less than about 4 lb/ft 3 ;   combining the first material and an additive to form a fourth material;   heating the fourth material to form a gas and a fifth material; and   combining the fifth material and the second material in a predetermined ratio to form an engineered fuel feedstock.   
     
     
         18 . The method of  claim 17 , further comprising:
 combining the third material with the first material and the additive to form the fourth material.   
     
     
         19 . The method of  claim 17 , wherein the fourth material is heated to a range from about 200° C. to about 350° C. 
     
     
         20 . The method of  claim 17 , wherein the fourth material is heated for a time of at least about 10 minutes. 
     
     
         21 - 30 . (canceled)