NOVELTY - Producing engineered fuel feedstock from a processed municipal solid waste (MSW) stream, involves: combining first waste stream that includes hard plastic, soft plastic and mixed plastic with sorbent; increasing the temperature of the combined first waste stream and sorbent to a temperature of at least 200 degrees C; combining the thermally treated first waste stream and sorbent with a second waste stream, where the second waste stream includes fiber; and compressing the combined first waste stream, sorbent, and second waste stream to form a densified engineered fuel feedstock.    USE - In producing an engineered fuel feedstock from a processed municipal solid waste (MSW) stream (claimed).    ADVANTAGE - The method produces an engineered fuel feedstock having significantly reduced chlorine content, that controls emissions, prevents corrosion, and/or improves operational performance during combustion or gasification applications.    DETAILED DESCRIPTION - A method of producing an engineered fuel feedstock from a processed municipal solid waste (MSW) stream, involves: either method (A) involving 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 200 degrees C; combining the thermally treated first waste stream and sorbent with a second waste stream, where the second waste stream includes fiber; and compressing the combined first waste stream, sorbent, and second waste stream to form a densified engineered fuel feedstock; or method (B) involving 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. An INDEPENDENT CLAIM is included for an engineered fuel feedstock made from a processed MSW waste stream, comprising: 5-50 wt.% of a plastic; 50-95 wt.% of fiber; 1-50 wt.% of sorbent; and less than 400 parts per million (ppm) chlorine.