改性渣使用湿老化的除机制及其作为回填材料的性能演变
Mengbo Zhu1, Liusheng Zhao2, Lang Liu1
1College of Energy Engineering, Xi'an University of Science and Technology, Xi'an, 710054, China; Key Laboratory of Western Mines and Hazards Prevention, Ministry of Education of China, Xi'an, 710054, China.
Journal of environmental management
|January 26, 2025
概括
这项研究涉及从煤矿回填中使用的改性渣 (MMS) 中释放的氨 (NH3). 使用3%含水率的潮湿老化方法,可以有效地减少80%以上的NH3释放,同时保持材料强度.
科学领域:
- 材料科学 材料科学 材料科学
- 地质技术工程 地质技术工程
- 环境科学 环境科学
背景情况:
- 改性渣 (MMS) 是煤矿回填的潜在水泥材料.
- 从MMS中释放的氨 (NH3) 造成了严重的环境和安全问题.
- 了解NH3释放的化学机制对于安全利用至关重要.
研究的目的:
- 为了解决煤矿回填中改性渣 (MMS) 释放的氨 (NH3) 问题.
- 调查从MMS释放的NH3的化学机制.
- 为减少NH3排放提出和验证有效的解决方案.
主要方法:
- 使用了单轴压力强度 (UCS),水化动力学,SEM,TG-DTG和XRD分析.
- 使用热化学理论和Pidgeon方法确定源 (Mg3N2,Li3N).
- 使用湿老化方法与连续在线气体检测系统来评估NH3释放.
主要成果:
- 确定Mg3N2和Li3N作为NH3释放的主要源.
- 3%的老化水含量显著减少了NH3释放的81.55%.
- 在老化水含量低于6%的情况下,UCS保持在3MPa以上,设定时间更短.
结论:
- 湿老化方法有效地减轻了基于MMS的回填物中的NH3释放.
- 最佳条件包括3%的老化水含量和7天的老化期,以减少NH3和足够的强度.
- 这种方法确保了MMS在煤矿回填中安全有效的应用.
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