Co-Processing Plastic Waste in Cokers for Jet Fuel Production

Abstract

Systems and methods are provided for co-processing plastic waste in a coker as part of an integrated refinery environment that produces kerosene, jet fuel, and/or jet fuel blending components as a product. The co-processing can be performed in a fluidized coker, a delayed coker, or a combination of fluidized cokers and delayed cokers. After coking, hydroprocessing can be performed on one or more portions of the coker effluent that contribute to formation of the kerosene, jet fuel, and/or jet fuel blending component product(s). The hydroprocessing can be used to reduce or minimize the presence of unexpected nitrogen contaminants in the resulting kerosene, jet fuel, and/or jet fuel blending component product(s).

1 . A method for co-processing a plastic feedstock, comprising:
 mixing a plastic feedstock with one or more additional feedstocks to form a feedstock mixture, the plastic feedstock comprising 25 wt % or less of at least one nitrogen-containing polymer relative to a weight of the plastic feedstock, the feedstock mixture comprising 0.5 wt % to 30 wt % of the plastic feedstock relative to a weight of the feedstock mixture;   exposing at least a portion of the feedstock mixture to coking conditions to form a conversion effluent comprising one or more amides, one or more amines, or a combination thereof;   separating the conversion effluent to form at least one liquid product fraction having a T10 distillation point of 300° C. or less and a T90 distillation point of 170° C. or more, the at least one liquid product fraction comprising a basic nitrogen content of 100 wppm or more relative to a weight of the at least one liquid product fraction; and   exposing at least a portion of the at least one liquid product fraction to hydroprocessing conditions to form a hydroprocessed effluent comprising a jet boiling range fraction having a total nitrogen content of 10 wppm or less relative to a weight of the jet boiling range fraction.   
     
     
         2 . The method of  claim 1 , wherein the basic nitrogen content of the at least one liquid product fraction comprises 20 wt % or more of the total nitrogen content of the at least one liquid product fraction. 
     
     
         3 . The method of  claim 1 , wherein the basic nitrogen content of the at least one liquid product fraction comprises 40 wt % or more of the total nitrogen content of the at least one liquid product fraction. 
     
     
         4 . The method of  claim 1 , wherein the at least one liquid product fraction comprises a basic nitrogen content of 150 wppm or more. 
     
     
         5 . The method of  claim 1 , wherein the at least one liquid product fraction comprises a basic nitrogen content of 300 wppm or more. 
     
     
         6 . The method of  claim 1 , wherein the at least one liquid product fraction comprises a total nitrogen content of 700 wppm or more. 
     
     
         7 . The method of  claim 1 , wherein separating the conversion effluent forms a plurality of liquid product fractions having a T10 distillation point of 300° C. or less, a T90 distillation point of 170° C. or more, or a combination thereof, and wherein exposing at least a portion of the at least one liquid product fraction to hydroprocessing conditions comprises exposing at least a portion of the plurality of liquid product fractions to hydroprocessing conditions to form a plurality of hydroprocessed effluents comprising a jet boiling range fraction having 10 wppm or less of basic nitrogen. 
     
     
         8 . The method of  claim 7 , wherein each of the plurality of liquid product fractions comprise 100 wppm or more of basic nitrogen. 
     
     
         9 . The method of  claim 1 , further comprising separating the hydroprocessed effluent to form the jet boiling range fraction and one or more additional hydroprocessed fractions having a T10 distillation point of 300° C. or higher. 
     
     
         10 . The method of  claim 9 , wherein separating the conversion effluent comprises forming at least one additional liquid product fraction having a T10 distillation point of 300° C. or higher, and wherein exposing at least a portion of the at least one liquid product fraction to hydroprocessing conditions further comprises exposing at least a portion of the at least one additional liquid product fraction to the hydroprocessing conditions. 
     
     
         11 . The method of  claim 1 , wherein separating the conversion effluent comprises forming at least one additional liquid product fraction having a T10 distillation point of 300° C. or higher, the method further comprising:
 exposing the at least one additional liquid product fraction to second hydroprocessing conditions to form a second hydroprocessed effluent; and 
 separating the second hydroprocessed effluent to form a second jet boiling range fraction and at least one additional hydroprocessed fraction having a T10 distillation point of 300° C. or higher. 
 
     
     
         12 . The method of  claim 1 , wherein at least one of the one or more additional feedstocks comprises a T10 distillation point of 300° C. or higher. 
     
     
         13 . The method of  claim 1 , wherein the plastic feedstock further comprises 5.0 wt % or less of at least one chlorine-containing polymer relative to a weight of the plastic feedstock. 
     
     
         14 . The method of  claim 13 , the method further comprising:
 maintaining the feedstock mixture in a vessel at a dechlorination temperature of 170° C. to 300° C. for 1.0 minute to 240 minutes to form a dechlorinated mixture of feedstocks,   wherein exposing at least a portion of the feedstock mixture to coking conditions comprises exposing at least a portion of the dechlorinated mixture of feedstocks to coking conditions.   
     
     
         15 . The method of  claim 13 , wherein the one or more additional feedstocks comprise a T10 distillation point that is greater than the dechlorination temperature. 
     
     
         16 . The method of  claim 13 , wherein the dechlorinated mixture of feedstocks comprises 1000 wppm or less of Cl relative to a weight of the dechlorinated mixture of feedstocks. 
     
     
         17 . The method of  claim 1 , wherein the plastic feedstock comprises plastic particles having an average diameter of 10 cm or less. 
     
     
         18 . The method of  claim 1 , wherein the one or more amides comprise caprolactam. 
     
     
         19 . The method of  claim 1 , wherein the coking conditions comprise fluidized coking conditions, delayed coking conditions, or a combination thereof. 
     
     
         20 . The method of  claim 1 , wherein the hydroprocessing conditions comprise a severity index of 3 to 10.