| 摘要 |
<p>A method and a device for the stabilisation of ash, preferably fly ash, are disclosed. In the method, the ash is first extracted with an acid aqueous solution, whereupon it is preferably washed with an aqueous solution before being alkalised with an aqueous solution of a water-soluble alkali, such as soda, and treated with an aqueous solution of a water-soluble sulphide, such as sodium sulphide, in order to convert leachable material in the ash to insoluble sulphide. The thus-stabilised ash is then washed, preferably with water. After each treatment stage, the ash is preferably separated from the liquid. The device consists of a band filter (15) having an inlet end for ash that is to be stabilised, as well as an outlet end for ash that has been stabilised. As seen from the inlet end to the outlet end, the band filter comprises a station (25) for acid extraction of the ash, a washing station (30), a station (36) for alkalisation of the ash, a station (42) for sulphide-treatment of the ash, and a washing station (48).</p> |
