Treating residues from incineration smoke of household waste/residual waste containing heavy metals e.g. lead and salts e.g. sulfate in aqueous medium, comprises conditioning waste in aqueous suspension for maturing in lukewarm

摘要

The process for treating a special industrial waste such as residues from the incineration smoke of household waste or residual waste containing heavy metals e.g. lead and salts e.g. sulfate in an aqueous medium, comprises conditioning the waste in an aqueous suspension for maturing in lukewarm to collect mature solid fraction, and subjecting the matured waste to repetitive solid/liquid washing-separation operation until the solid fraction reaches a desired level of non-harmful environment. The process for treating a special industrial waste such as residues from the incineration smoke of household waste or residual waste containing heavy metals e.g. lead and salts e.g. sulfate in an aqueous medium, comprises conditioning the waste in an aqueous suspension for maturing in lukewarm to collect mature solid fraction, and subjecting the matured waste to repetitive solid/liquid washing-separation operation until the solid fraction reaches a desired level of non-harmful environment. An accelerating agent such as sodium carbonate of less than 10 wt.% with respect to the waste to be treated is added to the fresh aqueous suspension for solubilizing kinetics of salts before maturing. The washing operation is carried out with water, where the cumulated weight ratio of repetitive solid/liquid washing-separation does not exceed 50. A prewash operation for the waste to be treated is carried out prior to the conditioning step. An independent claim is included for an installation for treating residues from the incineration smoke of household waste or residual waste containing heavy metals and salts in an aqueous medium.