页岩气水基钻井液抑制剂的抑制性能研究

Study on Inhibition Performance of Shale Gas Water-based Drilling Fluid Inhibitors

页岩气已经成为我国非常重要的能源之一。页岩地层黏土矿物含量高,页岩气水平井水平段长,钻井液与地层接触的时间增加,页岩水化更严重,井壁失稳更加突出。页岩气开发过程中钻井液与地层容易发生水化作用,使地层水化膨胀,影响井壁稳定性。因此水基钻井液必须首先作到能完全抑制黏土矿物的水化。通过流变性、滤失量、线性膨胀率对比研究了三种抑制剂。优选出了最佳抑制剂AT-JM,线性膨胀率最低。这为后面页岩气水基钻井液体系的优选提供了非常重要的参考。

Shale gas has become one of the most important energy sources in China. The shale formation has high clay mineral content,longer horizontal section of the shale gas horizontal well,which results in the contact time of drilling fluid and formation increases. And the shale hydration becomes more serious and borehole instability becomes more prominent. Water-based drilling fluid can completely inhibit clay minerals hydration in the first place. Three kinds of inhibitors were studied by comparison of rheology,filtration rate and linear expansion rate. The best inhibitor AT-JM with the lowest linear expansion rate was selected. This provided a very important reference for the optimization of the later shale gas water-based drilling fluid system.