垃圾焚化後產生大量焚化灰渣，其中飛灰因重金屬溶出量未能符合毒性溶出標準，被歸類為有害廢棄物，需經適當的處理。而飛灰之處理著重在固化與穩定化，但若能再資源化，更可創造新資材。 本研究先以水洗方式去除飛灰中可溶性物質，增加飛灰後續處理之穩定性，再以磷酸穩定重金屬，以減少重金屬溶出之潛勢，另一方面磷酸亦有助於提升後續燒結資源化之效果，穩定後之水洗灰以燒結熱處理技術將燒製成營建用骨材，以達資源化之目的。 由實驗結果得知，飛灰經過兩次水萃後，可有效的將易溶出的鹽類先萃出，氯鹽萃出率可達90%，水洗後之飛灰以適量之磷酸溶液做飛灰重金屬穩定處理，可有效降低Pb的再溶出， 使水洗灰符合TCLP標準。水洗灰經磷酸穩定後，添加適量黏土與淨水污泥，以1000與11000C燒結，成品已達營建骨材之條件，具回收再利用之可行性。 Municipal solid waste treatment method was treading toward incineration in Taiwan. A large amount of fly ash could be produced. The heavy metals concentration of fly ash failed to meet the EPA’s regulation of TCLP test thresholds. The de-toxicfication and stabilization for fly ash were necessary and the final aim is regeneration. This study was to develop a new process that could cheaply and stably treat the fly ash and regenerate the products. The process includes water-washing, phosphoric acid stabilization, and sintering. Washing could remove the soluble salts in the fly ash, which is harmful to the sintering process; the phosphoric acid could stabilize the heavy metals. The pretreated fly ash could be safely materialized by sintering technology. The study was found that fly ash after water washed twice, the soluble salt could remove 90%. After stabilized with proper dosage of phosphoric acid solution, the concentration of Pb were significantly reduced in the TCLP extract of the washed fly ash samples. Then the stabilized samples were mixed with designed percentage of water purification sludge and clay, and sintering at 1000 and 1100 0C. The sintered products could achieve the criteria for aggregate of construction that is possible to be regenerated.
