Unlocking the potential: Transforming hazardous waste into solid cementitious materials

Abstract

Incineration fly ash and mineral slag represent hazardous and industrial solid wastes necessitating immediate remediation in China. The liberation and stabilization of heavy metals have erected formidable barriers to their reclamation and repurposing. This study presents a pivotal technology for creating all-solid waste cementitious materials, with the optimal parameters consisting of a dosage of 55.773% incineration fly ash, 38.822% cementitious materials dosage, and 5.405% adhesive powders dosage. Furthermore, a comprehensive evaluation model has been developed to assess the performance of these materials. Several extraction procedure experiments were conducted to investigate the leaching behavior of heavy metals under various leaching scenarios, which suggests the diffusion coefficients of heavy metals under the optimal ratio are all less than 3 × 10–13 m2/s, affirming the effective stabilization and the absence of potential migration risks. The primary mechanisms of solidification involved include ion exchange reactions for charge balance and the encapsulation of precipitates through cementation, both of which contribute to the solidification of heavy metals. The findings will illuminate advanced strategies for reducing waste, enhancing resource efficiency, and promoting environmentally friendly building practices, as well as provide a promising avenue for achieving sustainability goals in construction projects, leading to reduced environmental impact and improved long-term sustainability. The integration of ACM-SW can pave the way for transformative advancements in sustainable building practices, ultimately leading to a more environmentally friendly and resilient built environment.