MASS TRANSFER OF COMPLEX CHEMICAL FLUID IN POROUS MEDIA
复杂化学流体在多孔介质中的传质

With the development of EOR (enhanced oil recovery) technology, chemical flooding technique has been switched from single chemical agent to complex chemical fluid to displace oil. In chemical flooding process, there exist a series of physical-chemical phenomena, such as: diffusion, dispersion, adsorption, retention, and chemical reaction etc. These phenomena will affect mass transfer of chemical agents in porous media. In this paper, the above physical-chemical phenomena are analyzed. It is proved by alkali aqueous solution displacing oil experiments that there exists motion lag for a single chemical agent when it is transferred in porous media. The motion lag and lag-difference for alkaline/surfactant/polymer complex system porous flow were also investigated, results show that the all-around adsorption will lead to motion lag. The lag-difference for different chemical agents lead to chromatographic separation phenomena'. Based on the above work, a adsorptive-convective-diffusive equation is established, and its analytical solution is obtained. Experimental data are treated by using this solution, and the lag coefficient and all-around diffusive coefficient in the equation were extracted, with these results, the mass transfer process for complex chemical fluid can be described and predicted.