Method for Converting Waste Plastic to Lower-Molecular Weight Hydrocarbons, Particularly Hydrocarbon Fuel Materials, and the Hydrocarbon Material Produced Thereby

Abstract

A method produces a hydrocarbonaceous fluid (a liquid mixture of hydrocarbons, or in other words a mixture of hydrocarbons which is liquid at ambient room temperature and atmospheric pressure), which functionally is a liquid hydrocarbon fuel, from a feed of waste plastic. The method comprises in broad embodiments the steps of: (step 1) melting a feed of substantially solid waste plastic in an aerobic atmosphere (for instance, air) whereby a waste-plastic melt is produced; (step 2) distilling at least a portion of the waste-plastic melt whereby a hydrocarbonaceous distillate is produced; and (step 3) collecting the hydrocarbonaceous distillate. That distillate is generally referred to above as a condensate. In some preferred embodiments, the method includes the step of commutating the feed of substantially solid waste plastic into pieces substantially no greater than about 1.5 cm 2 prior to step 1. In preferred embodiments, the method includes the step of adding an effective amount of a cracking catalyst to the waste plastic prior to step 2.

1 . A method for the production of a hydrocarbonaceous fluid from a feed of waste plastic comprising the steps of:
 (step 1) melting a feed of substantially solid waste plastic in an aerobic atmosphere whereby a waste-plastic melt is produced;   (step 2) distilling at least a portion of said waste-plastic melt whereby a hydrocarbonaceous distillate is produced; and   (step 3) collecting said hydrocarbonaceous distillate.   
     
     
         2 . A method for the production of a hydrocarbonaceous fluid from a feed of waste plastic according to  claim 1  further including the step of:
 prior to said step 1, commutating said feed of substantially solid waste plastic into pieces substantially no greater than about 1.5 cm 2 .   
     
     
         3 . A method for the production of a hydrocarbonaceous fluid from a feed of waste plastic according to  claim 1  further including the step of:
 prior to said step 2, adding an effective amount of a cracking catalyst to said waste plastic.   
     
     
         4 . A method for the production of a hydrocarbonaceous fluid from a feed of waste plastic according to  claim 1  wherein said step 1 and said step 2 are performed by the steps of:
 (step a) heating said feed of substantially solid waste plastic in an aerobic atmosphere in a vessel to melt and volatilize at least a portion of said feed of waste plastic to produce a stream of volatiles; and   (step b) condensing said stream of volatiles.   
     
     
         5 . A method for the production of a hydrocarbonaceous fluid from a feed of waste plastic according to  claim 1  wherein, in step 1, said feed of waste plastic is substantially a feed of linear, thermoplastic polymer. 
     
     
         6 . A method for the production of a hydrocarbonaceous fluid from a feed of waste plastic according to  claim 1  wherein, in step 1, said feed of waste plastic is substantially a feed of waste plastic selected from the group consisting of high-density polyethylene, low-density polyethylene, polypropylene and mixtures thereof. 
     
     
         7 . A method for the production of a hydrocarbonaceous fluid from a feed of waste plastic according to  claim 1  further including the step of:
 (step 4) after step 3, filtering said distillate.   
     
     
         8 . A method for the production of a hydrocarbonaceous fluid from a feed of waste plastic according to  claim 1  further including the steps of:
 (step 4) after step 3, filtering said distillate to produce a filtrate; and   (step 5) distilling said filtrate to produce a refined filtrate.   
     
     
         9 . A method for the production of a hydrocarbonaceous fluid from a feed of waste plastic according to  claim 1  further including the steps of:
 (step 4) after step 3, filtering said distillate to produce a filtrate;   (step 5) distilling said filtrate to produce a refined filtrate; and   (step 6) separately collecting a first fraction of said refined filtrate.   
     
     
         10 . A method for the production of a hydrocarbonaceous fluid from a feed of waste plastic according to  claim 1  further including the steps of:
 prior to said step 2, adding an effective amount of a cracking catalyst to said waste plastic;   (step 4) after step 3, filtering said distillate to produce a filtrate;   (step 5) distilling said filtrate to produce a refined filtrate; and   (step 6) separately collecting a first fraction of said refined filtrate.   
     
     
         11 . A hydrocarbonaceous fluid produced according to the method of  claim 1  and containing hydrocarbons within the liquid hydrocarbon fuel range. 
     
     
         12 . A hydrocarbonaceous fluid produced according to the method of  claim 9  and containing hydrocarbons within the liquid hydrocarbon fuel range.