Study on leaching characteristics of MSWIFA in different pH environment

Abstract

The change of leaching solution of waste incineration fly ash (MSWIFA) after shaking under different initial extractant pH was studied, and the change trend was compared with that of fly ash under different extractant concentrations. In addition, the leaching characteristics of heavy metals were analyzed under the two methods. The results showed that the pH change of the initial extractant can not truly simulate the environment of fly ash landfill, and the former can not reflect the pH of the final leaching solution. Changing the initial extractant concentration within a certain range can gradually change the final leaching solution from alkaline to acidic, which can truly reflect the environmental changes experienced by fly ash in the landfill (such as rainstorm scouring, drought and other environment). The leaching concentration of heavy metals in the leaching solution obtained by shaking fly ash under different acetic acid concentrations reflects the actual leaching characteristics of heavy metals under different pH conditions, in which Pb and Zn are amphoteric leaching, and the other metals are cationic leaching.