| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method wherein fly ash is stabilized by removing zinc and lead contained in fly ash, and the removed zinc and lead is recovered. SOLUTION: After the acid chemical 3 is added to fly ash 1 containing heavy metal such as zinc and lead to be discharged from an incinerator or a melting furnace, the solid is separated front the liquid, followed by the process (a) where the pH regulator 6 and the insolubilizing agent 7 are added to the filtrate containing zinc obtained through the solid-liquid separation to recover zinc as the insoluble 9, and the process (b) where the solubilizing agent 12 is added to the residue containing lead obtained through the solid-liquid separation to extract lead, the solid is separated from the liquid, and the insolubilizing agent 7 is added to the filtrate containing lead obtained through the solid-liquid separation to recover lead as the insoluble 16.</p> |
