Patent ID: 7893378

Claim:
A method of sorting an input waste material stream including a mixture of first and second materials, comprising: (a) passing said input waste material stream through an adjustable separator having at least one adjustable parameter, and separating said input waste material stream into a first output stream containing the majority of said first material and some contaminant second material, and a second output stream containing the majority of said second material and some contaminant first material; (b) adjusting the adjustable parameter; (c) monitoring the amount of contaminant second material in said first output stream, and the amount of contaminant first material in said second output stream, both before and after step (b), and generating a signal indicative of whether the combined amount of contaminant material has decreased; (d) further adjusting said adjustable parameter responsive to said signal, in a direction indicated by step (c) as being favorable to decreasing the combined amount of contaminant material in the first and second output streams.