| 摘要 |
PCT No. PCT/DK96/00117 Sec. 371 Date Nov. 21, 1997 Sec. 102(e) Date Nov. 21, 1997 PCT Filed Mar. 22, 1996 PCT Pub. No. WO96/29118 PCT Pub. Date Sep. 26, 1996A method for treatment of halogen-containing waste material, in particular PVC-containing waste material, is disclosed, wherein the waste material in a decomposition step is heated in a reaction zone in a substantially closed system essentially without addition of water to a temperature between 150 and 750 DEG C., preferably 250-350 DEG C., in the presence of a halogen-reactive compound selected from alkali and alkaline earth metal hydroxides, alkali and alkaline earth metal carbonates and mixtures thereof, so as to establish a controllable autogenous pressure substantially above atmospheric pressure, in a sufficient reaction time to convert essentially all halogen present in the waste material to alkali or alkaline earth metal halides, said closed system preferably also comprising a condensation zone, where water vapour and volatile compounds liberated from the waste material are condensed. The remanence obtained in the decomposition step is washed with an aqueous solvent, preferably pure water, and the soluble and insoluble parts of the remanence are separated. By this method the halogen is removed from the waste without uncontrolled emission of halogen-containing acids to the environment.
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