forming a plastic mixture comprising a plastic material and a carrier, wherein the carrier is a hydrocarbon carrier selected from the group consisting of: light coker gas oil, heavy coker gas oil, vacuum residue, bitumen, atmospheric residue, pitch from a solvent deasphalting unit, pyrolysis fuel oil, diesel, fluid catalytic cracking slurry oil, decant oil, aromatic solvents, and mixtures thereof;

heating the plastic mixture; and

combining the heated plastic mixture with a coker feedstock upstream of a coke drum.