论文标题: |
Reuse of soil-like material solidified by a biomass fly ash-based binder as engineering backfill material and its performance evaluation |
作者: |
Qin, Zhifa; Jin, Jiaxu; Liu, Lei; Zhang, Yi; Du, Yuelin; Yang, Yong; Zuo, Shenghao |
出版刊物: |
JOURNAL OF CLEANER PRODUCTION |
出版日期: |
45066 |
出版年份: |
2023 |
卷/期: |
|
DOI: |
10.1016/j.jclepro.2023.136824 |
论文摘要: |
The reuse of soil-like material (SLM) obtained from landfill mining as engineering backfill materials contributes to sustainable waste management. In this paper, a new biomass fly ash-based binder (BB) containing biomass fly ash (BFA), carbide slag (CS), and phosphogypsum (PG) is designed to solidify the SLMs. The mechanical prop-erties, permeability, microstructure, and physicochemical characteristics of the BB-solidified SLM are compre-hensively characterized. The optimum proportion of ternary BBs consisting of 80% BFA, 15% CS, and 5% PG was determined through tests on paste samples. The different landfill depths of SLMs show significant variability in solidification/stabilization (S/S) effects due to their different physicochemical properties. The mechanical and permeability properties of BB-solidified SLM improve with the increasing BB content and the age of solidifica-tion. Microstructural and phase analyses indicated the formation of significant amounts of ettringite crystals and C-(A)-S-H gels were generated by the pozzolanic reaction, forming a stable and dense microstructure. The var-iations in pH and conductivity were correlated with the development of mechanical properties. Moreover, the organic matter content and leached heavy metal content of SLM2 and SLM3 after S/S treatment did not exceed the specified limits. This study can provide theoretical guidance for the resource utilization of the stabilized/ solidified SLMs. |