Technology Innovation in Incinerator Fly Ash Sintering and Melting Brings Regional GHG Mitigation and Economic Benefits

Municipal solid waste incinerator fly ash (IFA) reutilization is energy-intensive with expenditure and secondary fly ash (Sec-FA) generation. Technology innovation and deployment are necessary for better IFA reutilization. Herein, potential benefits of technology innovation by fuel substitution, waste heat recovery and Sec-FA reuse of preferable plasma melting, fuel melting, and sintering technologies were evaluated by life cycle assessment (LCA) and life cycle costing (LCC). Results show that fuel melting and sintering could gain more environmental and economic benefits, respectively Technology innovation could bring environmental benefits and approximately 132 to 173 RMB/t IFA of economic profitability, among which waste heat recovery could gain 32-36% of economic optimization effect. A regional technology transition in China from plasma melting to fuel melting and technology innovation with waste heat and Sec-FA recovery shows GHG mitigation (0.48-0.79 Mt/yr) and economic benefits (322.21-537.02 million RMB/yr). Policy scenarios indicated that enterprise will lose approximately 360.70 RMB/t IFA if zero-subsidy is provided.