Abstract: A process and apparatus for reducing sludges, especially those sludges containing heavy metals and generated in electroplating, to a solid state where the toxic constituents of the waste are prevented from leaching. The process involves mixing a metallic soap with the sludge and then using low-temperature induction heating to form coacervate bonds that encapsulate the toxic waste particles in a pumice-like matrix. The apparatus allows a small amount of metallic soap to be thoroughly mixed through sludge and a continuous ribbon of the resulting putty-like waste to be fed into a series of microwave drying ovens and evacuation chambers. After the drying and dewatering sequences, the apparatus extrudes a pumice-like solid suitable for disposal in accordance with EPA regulations.

Abstract: A process and apparatus for reducing sludges, especially those sludges containing heavy metals and generated in electroplating, to a solid state where the toxic constituents of the waste are prevented from leaching. The process involves mixing a metallic soap or hydroxide with the sludge and then using low-temperature induction heating to form coacervate bonds that encapsulate the toxic waste particles in a pumice-like matrix. The apparatus allows a small amount of metallic soap to be thoroughly mixed through sludge and a continuous ribbon of the resulting putty-like waste to be fed into a series of microwave drying ovens and evacuation chambers. After the drying and dewatering sequences, the apparatus extrudes a pumice-like solid suitable for disposal in accordance with EPA regulations.