Mathematical Approaches to Study Microbially Induced Calcite Precipitation: A Review
摘要
MICP is a recent technique that utilizes biochemical processes to create barriers by calcium carbonate cementation and can be used for sealing leakage zones in geological formations. A major difficulty in practical applications of MICP is the predictive planning of its use and impact, since it involves a number of complexes interacting processes. While the basic chemistry and the flow processes are known, it is the exact quantitative description of the interactions and, in particular, the influence of the biofilm and the developing precipitates that pose challenges to achieving predictability. As per the literature available due to the versatile nature of MICP like growth of bacteria, ammonium transport, spread of calcite, detachment of biomass and reactive transport of nutrients and/or chemicals etc. there is a versatile use of mathematical differential equations and numerical (or implicit) methods to solve the partial differential equations. These mathematical approaches are very helpful for the development of mathematical models of MICP for the prediction and better applicability in in-situ conditions. Currently as per the literature available various mathematical models have been developed like Advective–Dispersive transport model, Reactive transport model, Darcy-scale model etc., these models work under above stated variable parameters and gives desirable results under certain assumption and limitations like chemical reactions follows the 1st order kinetics (while actually assimilation of ammonium NH+ ions take place etc.). Various simulation software is being used like PHT3D, OPEN-FOAM etc., to simulate the data and results. Therefore, there is an essence of a mathematical model to enhance the better predicting setup for MICP in practical use. Hence, this paper aims to provide a glance of current mathematical progress in a systematic way to deal with MICP technology effectively for the actual field conditions under different variables with minimal assumptions.