Cementation Mechanism of Microbe Cement

Microbe cement is a new generation of cement, which relies on microbial induced produced calcium carbonate precipitation consolidate loose particles to a whole body. In order to further explore the cementation process of microbe cement in loose sand particles environmental and explain the cementation mechanism of microbe cement, in this paper, the process of microbe cement binding loose sand particles in the dish are firstly analyzed by Scanning electron microscope (SEM) and Biological Microscope. Secondly, the loose quartz sand particles and loose sand particles treatment by microbe cement are analyzed by Infra-red spectra (IR) and X-ray photoelectron spectroscopy (XPS), respectively. The SEM results indicate that microbe in microbe cement are firstly absorbed on the surface of loose sand particles, and then the microbe react with mixture solution on the surface of loose sand particles to form calcite crystal. The biological microscope results show that microbe cement will form calcite crystal between the loose sand particles within 1.0 hour. The cementation process continues to about 5.0 hours, however, when the time continues to extend, the influence of microbe cement on cementation effect is little. The IR and XPS results indicate that there are organic matters in loose sand particles treatment by microbe cement and the organic matters interacts with calcite induced by microbe cement and sand particles to form hydrogen bond, which play a role in binding function between loose sand particles and calcite produced by microbe cement.