Resource utilization of municipal solid waste incineration fly ash - cement and alkali-activated cementitious materials: A review

The increase in municipal solid waste (MSW) production has led to an increase in MSW incineration fly ash (MSWIFA) production. MSWIFA contains toxic and harmful substances such as heavy metals and dioxins, which can cause harm to the environment if not treated properly. Only a few MSWIFAs will be landfilled directly, and the rest will need to be treated by other methods. The treatment of MSWIFA can be divided into three types: separation, stabilization/solidification (S/S), and thermal treatment, which are either not fully developed or too costly. Resource utilization is a sustainable means of treating MSWIFA. MSWIFA is used in the production of cement and alkali-activated cementitious materials as a means of resource utilization with significant advantages. This can alleviate the consumption of nature and reduce greenhouse gas emissions in conventional cement production. Compared with MSWIFA cement, MSWIFA alkali-activated cementitious material can be achieved with almost no consumption of natural resources, which is worthy of further research to realize the large-scale application of MSWIFA. At the end of the paper, the perspective of separation of dioxins from MSWIFA, co-processing of MSWI ash, and production of "MSWIFA green materials" is presented.