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This study explores the current state-of-the-art in the detoxification and valorization of solid residues from municipal solid waste incineration (MSWI), especially fly ash, using plasma vitrification. The principles and advances in hazardous material elimination, resource recovery, and system integration using plasma vitrification for MSWI fly ash are identified. The global production and the characteristics of MSWI fly ash are first reviewed. Then, the features and principles of plasma technologies used for MSWI fly ash treatment from the thermodynamic and physical aspects are provided. The mechanisms of detoxification of MSWI fly ash from the perspectives of dioxins destruction and metal separation by plasma vitrification are also discussed. Moreover, the recovery methods of valuable elements for vitrified slag are introduced. Finally, the improvement pathways of plasma vitrification processes from the domains of engineering performance, environmental impact, and economic viability are suggested. [ABSTRACT FROM AUTHOR]

In this study, a proposed integrated high-gravity technology for air pollution control, CO 2 capture, and alkaline waste utilization was comprehensively evaluated from engineering, environmental, and economic perspectives. After high-gravity technology and coal fly ash (CFA) leaching processes were integrated, flue gas air emissions removal (e.g., sulfate dioxide (SO 2 ), nitrogen oxides (NO x ), total suspended particulates (TSP)) and CO 2 capture were studied. The CFA, which contains calcium oxide and thus, had high alkalinity, was used as an absorbent in removing air pollution residues. To elucidate the availability of technology for pilot-scale high-gravity processes, the engineering performance, environmental impact, and economic cost were simultaneously investigated. The results indicated that the maximal CO 2 , SO 2 , NO x , and TSP removal efficiencies of 96.3 ± 2.1%, 99.4 ± 0.3%, 95.9 ± 2.1%, and 83.4 ± 2.6% were respectively achieved. Moreover, a 112 kWh/t-CO 2 energy consumption for a high-gravity process was evaluated, with capture capacities of 510 kg CO 2 and 0.468 kg NO x per day. In addition, the fresh, water-treated, acid-treated, and carbonated CFA was utilized as supplementary cementitious materials in the blended cement mortar. The workability, durability, and compressive strength of 5% carbonated CFA blended into cement mortar showed superior performance, i.e., 53 MPa ±2.5 MPa at 56 days. Furthermore, a higher engineering performance with a lower environmental impact and lower economic cost could potentially be evaluated to determine the best available operating condition of the high-gravity process for air pollution reduction, CO 2 capture, and waste utilization., (Copyright © 2019 Elsevier Ltd. All rights reserved.)