Stimulation of Indigenous Carbonate Precipitating Bacteria for Ground Improvement

3rd International Conference on Advances in Environment Research

生态环境科学;地球科学

Rajasekar, Adharsh^1 ; Moy, Charles K.S.^1 ; Wilkinson, Stephen^2

Department of Civil Engineering, Xi'An Jiaotong-Liverpool University, Suzhou, Jiangsu

215123, China^1

Department of Civil Engineering, University of Wolverhampton, WV1 1LY, United Kingdom^2

关键词: Carbonate formations;    Carbonate precipitation;    Engineering applications;    Field investigation;    Ground improvement;    Indigenous bacteria;    Inorganic precipitation;    Scanning electrons;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/68/1/012010/pdf
DOI  :  10.1088/1755-1315/68/1/012010

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

Calcite minerals are precipitated in soil through biomineralisation which can be either organic or inorganic in nature. Biomineralisation can be employed to improve ground conditions in its natural state. Usually, studies of applied biomineralisation are highly interdisciplinary involving expertise from engineers, chemists and microbiologists. In this paper, we study the potential of biomineralisation from indigenous bacteria present in soil. The soil samples were collected from a high permeable zone and the bacteria that inhabit the soil were stimulated at a temperature of 15°C. A cementation solution consisting of 500mM calcium chloride, urea and nutrient broth at a pH of 7.5 was added to the soil samples. Inorganic precipitation was found to be dominant and was more efficient when compared to organic precipitation. Carbonate precipitation data indicated that inorganic precipitation were 1.37 times better at carbonate formation in comparison to organic precipitation. Scanning Electron Microscopy analysis identified cementation bonds formed between soil particles. It was deducted that organic precipitation is dependent on temperature, and may take an extended time at such low temperature. The preliminary data presented in this paper suggests that the implementation of biomineralisation with in-situ microbes is promising but requires further laboratory and field investigation before being considered for engineering application.