Methods and systems for converting plastic to fuel

Abstract

A method for producing a vapor stream from waste plastic comprises providing a waste plastic feedstock into a reactor containing one or more residues produced from a previously heated source of waste plastic, and heating the waste plastic feedstock in the reactor to a temperature from about 125° C. to 500° C. to generate a vapor containing one or more hydrocarbons. The waste plastic feedstock can have a calcium to sodium mass ratio from about 0.0001 to 400 as measured by inductively-coupled plasma (ICP) spectrometry. The catalytic activity in the reactor may be provided through one or more constituent elements in the waste plastic feedstock or the one or more residues produced from the previously heated source of waste plastic.

What is claimed is: 
     
         1 . A method for producing a condensate from waste plastic, comprising:
 a. providing a waste plastic feedstock into a reactor containing one or more residues produced from a previously heated source of waste plastic, wherein the waste plastic feedstock includes at least one of a tire and an electrical component casing, and wherein said residue has a calcium-to-sodium mass ratio from about 0.0001 to 400 as measured by inductively-coupled plasma (ICP) spectrometry;   b. heating said waste plastic feedstock in said reactor to a temperature from about 125° C. to 500° C. to generate a vapor containing one or more hydrocarbons;   c. condensing said vapor to generate said condensate comprising said one or more hydrocarbons; and   d. collecting said condensate in a collection vessel, wherein said condensate comprises between about 20 g and 75 g of said one or more hydrocarbons per 100 g of said waste plastic and said one or more residues.   
     
     
         2 . The method of  claim 1 , wherein said waste plastic feedstock is heated in said reactor without any added external catalyst. 
     
     
         3 . The method of  claim 1 , wherein said waste plastic feedstock comprises one or more elements selected from aluminum, antimony, arsenic, barium, beryllium, bismuth, boron, cadmium, calcium, cesium, chromium, cobalt, copper, gallium, germanium, gold, hafnium, indium, iron, lead, lithium, magnesium, manganese, mercury, molybdenum, nickel, platinum, palladium, potassium, rhodium, iridium, osmium, ruthenium, rhenium, rubidium, scandium, selenium, silicon, silver, sodium, strontium, tantalum, tellurium, thallium, thorium, tin, titanium, tungsten, vanadium, zinc, and zirconium. 
     
     
         4 . The method of  claim 1 , wherein said waste plastic feedstock comprises two or more of said elements. 
     
     
         5 . The method of  claim 1 , wherein said waste plastic feedstock comprises three or more of said elements. 
     
     
         6 . The method of  claim 1 , wherein said waste plastic feedstock comprises four or more of said elements. 
     
     
         7 . The method of  claim 1 , wherein said waste plastic feedstock comprises five or more of said elements. 
     
     
         8 . The method of  claim 1 , wherein said calcium to sodium mass ratio is from about 0.005 to 400, as measured by ICP. 
     
     
         9 . The method of  claim 1 , wherein said calcium to sodium mass ratio is from about 0.0001 to 4, as measured by ICP. 
     
     
         10 . The method of  claim 1 , wherein said calcium to sodium mass ratio is from about 0.0001 to 0.04, as measured by ICP. 
     
     
         11 . The method of  claim 1 , wherein said residue comprises one or more elements selected from aluminum, antimony, arsenic, barium, beryllium, bismuth, boron, cadmium, calcium, cesium, chromium, cobalt, copper, gallium, germanium, gold, hafnium, indium, iron, lead, lithium, magnesium, manganese, mercury, molybdenum, nickel, platinum, palladium, potassium, rhodium, iridium, osmium, ruthenium, rhenium, rubidium, scandium, selenium, silicon, silver, sodium, strontium, tantalum, tellurium, thallium, thorium, tin, titanium, tungsten, vanadium, zinc, and zirconium. 
     
     
         12 . The method of  claim 11 , wherein said residue comprises two or more of said elements. 
     
     
         13 . The method of  claim 11 , wherein said residue comprises three or more of said elements. 
     
     
         14 . The method of  claim 11 , wherein said residue comprises four or more of said elements. 
     
     
         15 . The method of  claim 11 , wherein said residue comprises five or more of said elements. 
     
     
         16 . The method of  claim 11 , wherein said calcium to sodium mass ratio is from about 0.003 to 40, as measured by ICP. 
     
     
         17 . The method of  claim 11 , wherein said calcium to sodium mass ratio is from about 0.003 to 4, as measured by ICP. 
     
     
         18 . The method of  claim 11 , wherein said calcium to sodium mass ratio is from about 0.0001 to 0.04, as measured by ICP. 
     
     
         19 . The method of  claim 1 , wherein said temperature is from about 150° C. to 410° C. 
     
     
         20 . The method of  claim 1 , wherein said temperature is from about 125° C. to 375° C. 
     
     
         21 . The method of  claim 1 , further comprising one or more pre-processing steps selected from the group consisting of collection processes, sorting processes, size reduction processes, cleaning processes, drying processes, and weighing processes. 
     
     
         22 . The method of  claim 1 , further comprising one or more post-processing steps selected from the group consisting of collection processes, sorting processes, size reduction processes, cleaning processes, drying processes, and weighing processes. 
     
     
         23 . The method of  claim 1 , wherein said plastic feedstock is obtained from at least one source selected from a landfill, recycling center, waste processing facility, a household, a place-of-business, an eating establishment, an automotive salvage yard, an aircraft salvage yard, or a ship salvage yard. 
     
     
         24 . The method of  claim 1 , wherein said waste plastic feedstock further comprises high density polypropylene (HDPE), low density polypropylene (LDPE), polypropylene (PP), polystyrene (PS), polyvinylchloride (PVC), polyethylene terephthalate (PETE), synthetic rubber, and/or natural rubber. 
     
     
         25 . The method of  claim 1 , wherein said one or more hydrocarbons include alcohols, aldehydes, ketones, alkanes, alkenes, alkynes, and/or carboxylic acids. 
     
     
         26 . The method of  claim 1 , wherein said electrical component casing comprises a computer body or an electrical cable casing. 
     
     
         27 . The method of  claim 1 , wherein said tire is a rubber tire.