关键词: 生物胶结, 作用机理, 产脲酶菌

Abstract: Biodeposition on rock surface is a natural phenomenon. This paper reviews the mechanism and application of microbial induced calcium carbonate precipitation (MICP). During the process of MICP, the microorganisms decompose urea to produce CO2-3, further forming calcium carbonate precipitates with the addition of calcium source. As a result, the dispersive particles are coagulated as a whole. The main factors affecting the performance of MICP such as microbial species and concentration, calcium source type, and urease activity were analyzed， and three conclusions were obtained. Firstly, the mechanisms of various microbial mineralization are consistent, but the structure of the precipitate is different. The higher the microbial concentration, the more the precipitates amount is produced. Secondly, the different source of calcium affects the deposition process. Thirdly, urease activity involving the regulation of environmental factors such as pH and temperature is one of the main factors that affect precipitation rate. This paper also summarized the main application fields of MICP, namely preparing cement, solidifying soil, repairing cracks, self-repairing of concrete, alleviating the greenhouse effect, etc. The advantages of microbial cement over traditional cement were also concluded.

Key words: biocement, mechanism of action, urease producing bacteria