播种可以提高生物瓦的强度,这些生物瓦是通过微生物诱导的碳酸沉来种植的
Emma Jane Horn1, Robert Huddy2, Dyllon Garth Randall3
1Civil Engineering Department, University of Cape Town, Cape Town 7700, South Africa.
The Science of the total environment
|August 21, 2024
概括
这项研究使用微生物诱导的碳酸沉 (MICP) 增强了生物的强度,采用了晶体播种和抽方法,避免了添加剂. 优化播种和抽水实现了符合国际标准的高强度生物.
科学领域:
- 材料科学 材料科学 材料科学
- 生物技术是生物技术.
- 土木工程 土木工程是指土木工程.
背景情况:
- 传统具有显著的环境影响.
- 生物提供了一个可持续的替代品,使用微生物诱导的碳酸沉 (MICP).
- 以前的生物生产需要化等添加剂来满足强度标准.
研究的目的:
- 在不使用化的情况下提高生物的强度性能.
- 调查CaCO3晶体播种的有效性和用于增强生物生产的抽方法.
- 为了优化MICP条件,使生物具有卓越的机械性能.
主要方法:
- 采用了一种新的抽水方法,通过密封的模具循环化溶液.
- 该研究利用在地质织品上的CaCO3晶体播种来增强MICP过程.
- 应用了优化的尿溶性Sporosarcina pasteurii度和编程的治疗保留时间.
主要成果:
- 在高细菌度 (40 mmol NH4-N/L·min) 和短保留时间 (1 小时) 的情况下,实现了最高的生物破裂强度.
- 种植前使用CaCO3晶体的地质织品显著提高了21-82%的破裂强度,与种子负载直接相关.
- 最高的种子负载 (0.072 g/cm2) 产生了符合挤出国际标准的生物 (940 ± 92 N,16.4 ± 1.7 N/mm2,6-10%的吸水率).
结论:
- 在生产高强度生物瓦方面,CaCO3晶体播种和抽方法是有效的.
- 这种方法消除了对化的需求,减少了离子强度问题.
- 优化的生物生产符合国际标准的强度和吸水能力,提供可持续的建筑材料.
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