悬浮液中固相微粒吸附系数的研究

Adsorption coefficient of solid mote in suspending fluid

由于传质扩散吸附方程的解析解不易求得,故对溶液体系中岩心的吸附系数大多按常数处理,但就悬浮液体系而言,其吸附作用对岩心驱替过程的影响要远大于扩散作用,按常数处理吸附系数会导致结果失真,尝试建立了悬浮液体系浓度分布数学模型,并采用数值模拟和实验相结合的方法对悬浮液体系吸附系数的测量及其性质做尝试性研究。采用该方法只需对一定体积量流体的平均浓度做一次测量,通过拟合即可求出吸附系数,降低了常规方法的实验误差,计算模型考虑了吸附系数随时间呈线性变化和岩心吸附饱和的情况,可求出吸附系数的初始值,可以模拟出岩心各处不同时刻的浓度值。通过实验验证了模型的准确性和方法的可行性。

As the analysis solution of the adsorption equation is difficult to find, the adsorption coefficient is regarded as constant in the solution. For suspension, adsorption has further influence on core displacement than diffusion. So adsorption coefficient treated as constant would cause distortion. A mathematical model is established for the system of suspension, and a method that combines numerical stimulation with experiments is presented, in which only the average concentration of the fluid is needed, the adsorption coefficient could be fitted by adjusting the parameters, as a result, the error of experiments is cut down. In the system, the linear change of adsorption coefficient with time and adsorption extent is considered, and the initial value of the adsorption coefficient could be deduced. The model can simulate the concentration of the suspension in the different position at random time. The accuracy and practicability of the method are verified by experiments.