Investigation on the carbonation and heavy metals stabilization of MSWI fly ash by incorporating γ-C2S and Portland cement

Accelerated carbonation is an effective method for treating municipal solid waste incineration fly ash (MSWI FA). However, the CO2 2 sequestration efficiency and the heavy metals (HMs) stabilization efficiency in accelerated carbonation are limited. In this study, gamma- C 2 S was introduced to enhance the sequestration efficiency of CO2 2 and the stabilization of HMs in MSWI FA. The study revealed that the inclusion of gamma- C 2 S significantly improved the compressive strength of the samples, leading to a 400 % increase in strength compared to the hydrated samples. The introduction of gamma- C 2 S increased the CO2 2 uptake of MSWI FA blended samples and reduced the leaching concentration of HMs. The experimental CO2 2 uptake after powder carbonation exceeded expectations. The carbonation of gamma- C 2 S and MSWI FA produced finer calcite particle size, which could act as seeds to enhance the carbonation reaction. This study offers a solution for the environmentally friendly and zero-carbon preparation of gelling material from MSWI FA.