Patent ID: 6213306
Filing Date: 2001-04-10
Classification: B03B,B29B,B29K,Y02W,Y10S

Abstract:
A process for separating, according to general type, various components of collected recoverable material refuse supplied as raw material in the form of fractionated pieces, comprising:soaking the raw material in a fluid to effect at least one of dissolving, parting and peeling of any soluble components which may be present therein from a remainder of said raw material;introducing said raw material to a horizontal fluid flow to liberate moist raw refuse from relatively heavy component materials disruptive to carrying out subsequent steps, a composition of said moist raw refuse being dependent upon on a relative sinking speed of each of the various components of the raw material in the horizontal fluid flow, the moist raw refuse being carried in the horizontal fluid flow and collected therefrom at a position horizontally offset from a position of introduction, and the relatively heavy component materials falling downward through the horizontal fluid flow without being carried horizontally as far as the collected moist raw material;crushing the moist raw refuse to a chip size of less than about 55 mm to form crushed raw refuse, said step of crushing resulting in generation of frictional heat contributing to simultaneous drying of the moist raw refuse;segregating out recoverable material components from the crushed raw refuse such that a remaining mixture is substantially a mixture of different types of recyclable plastic, each of said different types having unique chemical properties including density, said step of segregating out including at least one of segregating out particulate and relatively lighter substances than a remainder of said crushed raw refuse by centrifugation and segregating out metals magnetically; andseparating the mixture of different types of recyclable plastics according to a float-and-sink method in which the mixture of different types is placed in a separation fluid of suitably selected density such that at least one of said different types of plastic floats and at least another of said different types of plastic types sinks in said fluid.