Reduction of porous media permeability from in situ bacterial growth and polysaccharide production.

作者：Raymond E. Lappan · 发表于：Deep Blue (University of Michigan) · 年份：1994 · 被引用次数：4 · 研究领域：biodegradable polymer synthesis and properties

In situ core-plugging experiments and transport experiments, using the model bacteria Leuconostoc m., have been conducted. Results demonstrated that cellular polysaccharide production increases cell retention in porous media and causes an overall decrease in media permeability. Further, a parallel-core-plugging experiment was conducted and showed the feasibility of this system to divert injection fluid from high-permeability zones into low-permeability zones within porous media as is needed for profile modification. To implement this type of application, however, controlled placement of cells and rates of polymer production are needed. Therefore, kinetic studies were performed. A kinetic model, i.e. the modeling of the production of cells and polysaccharides, was subsequently developed for Leuconostoc m. bacteria. This model is based on data generated from batch growth experiments and allows for the prediction of saccharide utilization, cell generation, and dextran production. These predictions can be used to develop injection strategies for field implementation. Additional core plugging experiments have also been performed to determine the effects of the nutrient injection rate and nutrient concentration on the rate of porous-media plugging. As shown experimentally and as predicted by a model for in situ growth, an increase in nutrient concentration and/or its injection rate will result in a faster rate of porous-media plugging. Through continuum model simulations, it has be...