| 摘要 |
PROBLEM TO BE SOLVED: To recover valuable metals contained in waste, e.g. municipal refuse incineration ash or sludge, at low costs.SOLUTION: A method of recovering valuable metals from a cement production process using a cooling tower 3 for cooling the whole of combustion gas discharged from a cement baking furnace (ecological cement kiln 2, etc.) using waste as raw material and/or fuel, an exhaust gas treatment apparatus 1 for treating exhaust gas G1 from the cooling tower, and a path which returns dust recovered by the exhaust gas treatment apparatus to the cement baking furnace comprises recovering dust contained in the exhaust gas from the cooling tower and washing the recovered dust with water to recover dust containing valuable metals. The washed dust may be subjected further to an acid exudation step and an alkali exudation step to recover dust containing valuable metals as a calcium precipitation CA. |
