Patent ID: 7799835

Claim:
A method comprising: (a) separating a waste stream that includes plastic waste, such that at least a portion of non-plastic waste, unplasticized polyvinyl chloride (UPVC), plastics treated with a fire retardant, or a combination thereof is separated from the waste stream, thereby providing a plastic waste; (b) reducing the size of the plastic waste; (c) analyzing the plastic waste, in which analyzing includes: projecting an infrared light through the plastic waste to one or more detectors sufficient to provide a spectral content, the infrared light having at least two distinct frequency components; analyzing the spectral content of the infrared light transmitted through the plastic waste; and comparing the spectral content of the infrared light transmitted through the plastic waste to known spectral content profiles for two or more materials to determine which of the two or more materials comprise the plastic waste; (d) removing solid particles, organic matter, contaminants, metal contaminants, or a combination thereof, from the plastic waste; (e) calibrating an infrared (IR) source to the plastic waste, wherein the calibrating occurs after analyzing; (f) contacting the plastic waste with infrared (IR) energy at one or more frequencies and at one or more intensities, over a period of time effective to heat plastic present in the plastic waste; (g) contacting the plastic waste with infrared (IR) energy at one or more frequencies and at one or more intensities, over a period of time effective to alter the volume of the plastic waste; (h) contacting the plastic waste with infrared (IR) energy at one or more frequencies and at one or more intensities, over a period of time effective to reduce the weight of the plastic waste; and (i) cooling the heated plastic waste; thereby effectively providing recycled plastic, reduced plastic, or a combination thereof.