使用碳酸酶产生细菌进行粘土稳定的一项电动力学生物水泥化研究
Wilson Mwandira1, Maria Mavroulidou2, Anjali Satheesh1
1Division of Civil and Building Services Engineering, London South Bank University, London, UK.
Environmental science and pollution research international
|September 13, 2023
概括
使用碳酸酶 (CA) 和电动力学处理的生物凝固可显著加强铁路基础设施的粘土土. 这种方法利用本地细菌捕获二氧化碳,增强土壤强度并帮助缓解气候变化.
科学领域:
- 地质技术工程 地质技术工程
- 环境工程 环境工程
- 微生物学 微生物学
背景情况:
- 铁路基础设施需要坚固的土壤基础.
- 生物水泥化为传统的土壤改善方法提供了一个可持续的替代方案.
- 碳酸 (CA) 生物凝固利用二氧化碳封存用于水泥生产.
研究的目的:
- 评估电动力学CA生物水泥化的可行性,以加强粘土土壤.
- 为了比较这个应用的生物刺激和生物增强方法.
- 评估对土壤强度,水分和碳酸含量的影响.
主要方法:
- 粘土土样本的电动处理.
- 用CA产生细菌进行生物刺激和生物增强.
- 无排水切削强度测量的圆穿透测试.
- 含水量和碳酸分析.
- 扫描电子显微镜 (SEM) 用于结构分析.
主要成果:
- 生物刺激使未排水的剪切强度从17.6kPa增加到106.6kPa.
- 在生物刺激土壤中,SEM揭示了显著的结构变化.
- 生物增量导致CaCO3沉和细菌存在,但强度增加较低.
- 湿度含量和碳酸含量受到处理的影响.
结论:
- 通过生物刺激进行电动力学CA生物化,有效加强粘土土壤.
- 这种方法提高了铁路基础设施的弹性,并通过二氧化碳捕获促进了气候变化缓解.
- 对生物增强的进一步研究可能会优化其性能.
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