CFD Microfluidics Study in Porous Media Applied for Ex-Situ Biosurfactant Flooding

CFD Microfluidics Study in Porous Media Applied for Ex-Situ Biosurfactant Flooding

-In this study computational fluid dynamics (CFD) was applied to simulate the microbial enhanced oil recovery (MEOR) process into a micromodel with non-uniform pattern. One of operating methods of MEOR is ex-situ injection that is studied in this work. The porous medium was built using Matlab 2013 and Gambit 2.4.6, and Ansys Fluent 17.2 was used for solving governing equations. Grid independency analysis was done and numerical results were grid independent. Simulation results for water flooding were compared with experimental data and very good agreement was observed. In order to evaluate the performance of produced biosurfactant from Enterobacter cloacae subsp with PTCC: 1798, flooding tests were performed into the micromodel. As biosurfactant’s concentration is an important factor affecting the surface tension; here it is assumed that the injected fluid contains biosurfactant with concentration of 100 mg/lit. It is worthy to note that this concentration is the minimum amount of surfactant for micelle formation. Numerical results show that biosurfactant can improve recovery factor up to 1.45 times of primary recovery factor. But, numerical data illustrate increase of pressure drop in biosurfactant flooding compare to water flooding. Also an increment in fluid velocity in biosurfactant flooding was observed. Based on simulation data, there is an operation challenge to MEOR process and it is pressure drop of this method compared with water injection. Injection in higher pressures may effect on bioproducts performance. In addition, it looks that powerful equipment is needed and this means more cost for extracting oil from reservoirs. Also, results present that trapping number, dimension less number introduced in this research, of biosurfactant flooding is less than water flooding, so it will be more efficient.