| 摘要 |
In the cleaning of flue gases formed during the combustion of coal, preferably pulverised coal, the flue gases in a first step are cleaned of particulate pollutants, so-called fly ash, in a first separator (5). In a subsequent step, the flue gases are cleaned of gaseous, acidifying pollutants by mixing the flue gases with a sorbent in the form of a dry powder or fine water droplets in a contact reactor (21). The resulting reaction products are then separated together with unreacted sorbent as a dry powder from the flue gases in a second separator (41). Water is added to the fly ash separated in the first separator (5). The fly ash is then milled in a mill (11) in order to convert the calcium oxide and silicon dioxide present therein into calcium hydroxide and calcium silicates. Also, the fly ash is mixed with burnt or slaked lime and/or silicon dioxide prior to or after milling. The thus treated material is then used as sorbent in the subsequent cleaning step. |
