Patent ID: 6036484
Filing Date: 2000-03-14
Classification: F23G

Abstract:
A process for reprocessing slag and/or ash from the thermal treatment of refuse, comprising: receiving refuse that has been pyrolyzed, gasified or partially combusted to form a heavy-metal-containing slag and/or ash having a comparatively high carbon content, heating the slag and/or ash in a rotary kiln to a temperature below the melting temperature of the slag and/or ash, retaining the slag and/or ash in the rotary kiln for a sufficiently long time that the heavy metals present therein are converted into their metallic form by reduction at the carbon endigenous to the slag and the readily volatile heavy metals are transferred to the gas phase and are discharged from the rotary kiln together with the flue gas, and discharging the slag depleted in heavy metals from the rotary kiln.