Abstract: An apparatus for sorting plastic pieces by specific gravity sorting includes a vessel containing water and having an inlet for plastic pieces to be sorted, a device for introducing plastic pieces to be sorted into the vessel through the inlet, a device for removing air bubbles from the plastic pieces within the water, and a device for moving the plastic pieces within the water in the vessel to allow the various plastic pieces to be sorted within the water due to the different specific gravities of the plastic pieces. A method of sorting plastic pieces by specific gravity sorting with the apparatus is also described.

Abstract: A waste disposal system includes a stock yard for storing waste articles, a pre-treatment apparatus for separating a metal bulk from each waste article fed from the stock yard, a cryogenic crushing apparatus for crushing the separated metal bulk, and a crushing apparatus for crushing the portion of the waste article other than the metal bulk. The system further includes a light-weight article separating apparatus for separating the crushed waste from said crushing apparatus into foamed material and other wastes, and a foaming agent collecting apparatus which separates the foamed material into solid plastics and gaseous foaming agent and then cools and liquefies the gaseous foaming agent.

Abstract: A waste disposal system includes a stock yard for storing waste articles, a pre-treatment apparatus for separating a metal bulk from each waste article fed from the stock yard, a cryogenic crushing apparatus for crushing the separated metal bulk, and a crushing apparatus for crushing the portion of the waste article other than the metal bulk. The system further includes a light-weight article separating apparatus for separating the crushed waste from said crushing apparatus into foamed material and other wastes, and a foaming agent collecting apparatus which separates the foamed material into solid plastics and gaseous foaming agent and then cools and liquefies the gaseous foaming agent.

Abstract: A waste disposal system includes a stock yard for storing waste articles, a pre-treatment apparatus for separating a metal bulk from each waste article fed from the stock yard, a cryogenic crushing apparatus for crushing the separated metal bulk, and a crushing apparatus for crushing the portion of the waste article other than the metal bulk. The system further includes a light-weight article separating apparatus for separating the crushed waste from said crushing apparatus into foamed material and other wastes, and a foaming agent collecting apparatus which separates the foamed material into solid plastics and gaseous foaming agent and then cools and liquefies the gaseous foaming agent.