Abstract

Abstract The heavy metal (HM) evaporation in the thermal treatment of fly ash (FA) from municipal solid waste incineration (MSWI) has attracted considerable attention because the inhalation of or skin exposure to heavy metal raises human health risks. In this study, the washing and chemical treatments of FA were performed to inhibit the evaporation of HM (Zn, Pb and Cd) followed by a volatilization test of the pretreated FA at a temperature of up to 1000 °C. The results indicate that the evaporation behavior of HMs in fly ash was significantly affected by chemical speciation. The evaporation ratios of HMs with different speciations decreased in the order of acid soluble (F1) > reducible (F2) > oxidizable (F3) > residual (F4). The washing pretreatment process on fly ash would largely inhibit the evaporation of HMs by removing most of the metal chlorides, which are the dominant component of the F1 fraction. Meanwhile, the fly ash after phosphate chemical pretreatment has the least evaporation via converting the F1 fraction into the chemically stable F4 fraction. Therefore, the controllable formation of chemical speciation could effectively inhibit HM evaporation in fly ash.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.