Patent ID: 6416691
Filing Date: 2002-07-09
Classification: B09B,B09C,C04B,Y02W

Abstract:
A process for converting environmental contaminants present in finely divided waste materials into an environmentally non-toxic synthetic aggregate, wherein the finely divided waste material comprises at least 65 weight % of said synthetic aggregate, and wherein the environmental contaminants are selected from the group consisting of hydrocarbons, heavy metals, chlorides, carbon, pesticides, and mixtures thereof, the process comprising:(a) selecting the waste material so that it has the following particle size distribution: (i) a minimum of 5 weight % having a particle size less than about 80 microns; (ii) not more than 10 weight % having a particle size greater than 1 mm; (iii) not more than 5 weight % having a particle size greater than 3 mm; (iv) not more than 2 weight % having a particle size greater than 5 mm; (b) preheating elemental sulfur to form a molten sulfur binder; (c) preheating the waste material to substantially the same temperature as the molten sulfur binder; (d) contacting the preheated waste material with the molten sulfur binder in the absence of a chemical stabilizer to form a molten composition of the waste material encapsulated within the sulfur binder; (e) separating the molten composition into discrete particles to thereby form the synthetic aggregate, wherein the environmental contaminants are immobilized within the synthetic aggregate, and wherein the synthetic aggregate is substantially environmentally non-toxic.