摘要 |
A treatment method for reducing the leachability of selenium contained in a sodic fly ash which is provided by a combustion process when a sodium-based sorbent comes in contact with a flue gas generated by combustion to remove at least a portion of pollutants contained in the flue gas. The method comprises: (a) contacting the sodic fly ash with at least one additive in the presence of water; and (b) drying the material (preferably a paste) from step (a) to form a dried matter. The additive may comprise at least one strontium-containing compound, at least one barium-containing compound, dolomite, a dolomite derivative such as calcined or hydrated dolomite, at least one silicate-containing compound, or any combinations of two or more thereof. A particularly suitable additive may comprise strontium chloride, strontium hydroxide, pulverized dolomitic lime, sodium silicate, or any combinations of two or more thereof. |