使用水泥和燃料飞灰的二元系统稳定/固化受重金属污染的水泥土
Shamsad Ahmad1,2, Ashraf A Bahraq3, Hammad R Khalid4,3
1Department of Civil and Environmental Engineering, King Fahd University of Petroleum & Minerals, 31261, Dhahran, Saudi Arabia. shamsad@kfupm.edu.sa.
Environmental monitoring and assessment
|December 1, 2023
概括
燃料飞灰 (FFA) 可以部分取代普通波特兰水泥 (OPC) 稳定重金属污染的泥土. 这种环保方法符合强度和漏要求,提供可持续的废物管理解决方案.
科学领域:
- 环境工程 环境工程
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
背景情况:
- 土壤受到重金属的污染对环境构成重大风险.
- 稳定/固化 (S/S) 是污染土壤的关键修复技术.
- 普通波特兰水泥 (OPC) 是一种常见的稳定剂,但其使用对环境有影响.
研究的目的:
- 调查使用燃料飞灰 (FFA) 作为OPC的部分替代品在污染重金属的海土壤的S/S处理中的可行性.
- 评估OPC-FFA混合物在固定重金属和改善土壤特性方面的有效性.
主要方法:
- 马尔土壤被钢铁和电废物污染.
- 包括OPC和FFA在内的稳定剂被混合在10%-40%的剂量中与受污染的土壤.
- 评估了物理 (密度,多孔性,透性,不受限制的压力强度 - UCS) 和化学 (毒性特征漏程序 - TCLP) 属性.
主要成果:
- 加入FFA增加了孔隙性和透性,同时降低了密度.
- 随着FFA含量增加,UCS值下降,但仍然高于USEPA的0.35MPa的最低要求.
- TCLP的分析证实了有效的金属固定,而钢废污染的负面影响比电废物更大.
结论:
- 可以有效地使用FFA作为OPC的部分替代品,用于重金属污染的土的S/S处理.
- 拟议的方法表明了对环境友好的土壤整治和工业废物利用的潜力.
- 建议使用XRD,SEM和FTIR进行进一步的研究,以阐明S/S机制.
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