生物矿化过程的CaCO3 沉诱导的细菌粘性及其潜在的应用在微生物自我愈合的混凝土
Zhenfang Li1, Aizhu Liu1, Chunhui Sun1
1Shandong Hi-Speed Urban & Rural Development Group CO., LTD, Shang Dong, Jinan, 250014, China.
Applied biochemistry and biotechnology
|July 13, 2023
概括
微生物诱导的碳酸沉 (MICP) 有效地修复了早期的混凝土裂. 这种环保方法利用细菌沉石,达到95%以上的裂关闭和87%的水透性修复.
科学领域:
- 生物矿物化 生物矿物化
- 微生物诱导的碳酸沉 (MICP)
- 环境科学 环境科学
背景情况:
- 微生物诱导的碳酸沉 (MICP) 是一种天然的生物矿物化过程.
- 在材料科学和环境修复方面,MICP有潜在的应用.
- 了解MICP的参数对于优化其使用至关重要.
研究的目的:
- 调查环境因素对MICP细菌生长和碳酸酶活性的影响.
- 开发和评估用于早期混凝土裂修复的微生物治愈剂.
- 使用MICP评估混凝土的自我愈合效率.
主要方法:
- 研究了温度,初始pH值和Ca2+度对细菌活动的影响.
- 用细菌子和酸制备了一种微生物治愈剂.
- 评估混凝土裂修复,使用裂关闭率和水透度测量.
- 使用X射线衍射 (XRD) 识别沉物的组成.
主要成果:
- 发现了细菌生长和碳酸酶活性的最佳条件 (30°C,pH8.0-11.0,0-90mM Ca2+).
- 在28天后,达到了95.62%的裂关闭和87.54%的水透性修复,最大0.339毫米的裂.
- 在XRD分析中证实了裂部位的石 (CaCO3) 沉.
结论:
- MICP是一种有效和环保的方法,用于自我修复混凝土裂.
- 开发的微生物修复剂在裂修复和恢复水的透性方面表现出高效率.
- 这项研究提供了一种新的方法,用于使用生物矿物化的可持续混凝土修复.
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