method and apparatus for removing mercury from waste sludge of processes using mercury compounds as catalysts

摘要

1524464 Recovering mercury ANIC SpA 3 May 1976 [5 May 1975] 18035/76 Heading C7D Mercury is removed from a mercury-containing sludge by distillation under reduced pressure followed by two-stage condensation of the vapour, the bulk of which is condensed at sub-stmospheric pressure and the residue at super atmospheric pressure. Preferred conditions are distillation at 200-350‹C and -0À06 to -0À10 atmosphere gauge, followed by secondary condensation at 2-3 atmospheres and 5-35‹C. As particularly described, sludge is dried and roasted in oven 1, the residual ash being discharged to barometric dissolver 15 through which water is circulated by pump 17. Primary condensation of mercury takes place in condenser 18, the vapours from which are drawn off by a pump 23 and passed to high-pressure condenser 24.