影响咸淡水界面水敏性的几个因素

文章通过砂柱的水击试验,对水流速度、盐浓度、pH值对咸淡水界面水敏性的影响进行了研究。试验结果表明,咸淡水界面上存在临界盐浓度值和临界流速值,当入流溶液浓度达到临界盐浓度和流速达到临界流速时,都会产生颗粒释放现象,导致砂柱的渗透率下降,水敏性发生。在相同的盐浓度和进水流速条件下,进水的pH值越低,颗粒释放的速度越慢,释放总量越少;进水的pH值越高,颗粒释放的速度越快,释放总量越多。

Factors affecting the water sensitivity of saltwater-freshwater interface

Experiments were conducted to study the effect of salt concentration,fluid flow rate and value of pH on the water sensitivity of saltwater-freshwater interface through water shocking experiments in a sand-column.The results indicate that critical salt concentration and critical flow rate exit on the saltwater-freshwater interface.The phenomena of fine particles release may be observed when the fluid conditions reach to the critical salt concentration and critical flow rate,which can induce the permeability reduction and water sensitivity of the sand-column.According to the experiments of different values of pH,conclusions can be drawn that at the same salt concentration and flow rate,the lower of the pH,the more slowly of the fine release,the less of total quantity.Whereas,the higher of the pH,the faster of the fine release and the more of the total quantity.