外加直流电场对储层渗透率的影响

Effect of impressed DC electric field on the reservoir permeability

建立了外加直流电场作用下储层绝对渗透率因数与双电层厚度的数学模型 ,其定性结论与实验结果相符 .在外加直流电场作用下 ,双电层厚度对低渗透储层绝对渗透率的影响大 ,而对高渗透储层的绝对渗透率的影响相对较小 .对于低渗透天然岩心 ,其有效绝对渗透率因数随电场强度增大而单调递增 ,且其值很大 ,而高渗透天然岩心的有效绝对渗透率因数提高的幅度较小 .因而 。

The mathematical models of the relationship of reservoir absolute permeability coefficient and electronic double layer thickness under the impressed DC electric field are established. Under the impressed DC electric field, the electronic double layer thickness affects absolute permeability of the low permeable reservoir greatly and absolute permeability of high permeable reservoir diminutively. Experimental results indicate that the effective absolute permeability coefficient increases greatly with the electric field strength increase in the low permeable natural core, but increase slowly in the high permeable natural core. Thus, the potential of utilizing impressed DC electric field to improve permeability of the low permeable reservoir is great.