摘要:Municipal solid waste incineration fly ash from Chongqing has been sampled and investigated the phase composition, major elements composition and content of heavy metal. Water-leaching, acid-leaching and multiple-step nitric acid-water-leaching process was applied to leach the MSWI fly ash, sequential extraction procedure was used to monitor the fraction and bioavailability change of heavy metals. Water-leaching process showed low efficiency on remove of heavy metals but high efficiency on reduce the bioavailability of heavy metals from fly ash Acid leaching process can remove the heavy metal efficiency but changed the fraction distribution of heavy metals which activated the heavy metal. Multiple-step leaching process was the most efficient process to achieve double effect that reduced the content and potential availability of heavy metal in fly ash in the meantime.