水基钻井液中天然气水合物形成实验研究

Experimental Study of Natural Gas Hydrate Formation in Water Based Mud

在钻探过程中,当温压条件合适,钻井液易形成天然气水合物,造成管线堵塞、钻井液性能变化。研究2种水基钻井液对绿峡谷气水合物形成过程中的影响。结果表明实验条件下该2种水基钻井液很易形成水合物,受钻井液组分的影响,两种钻井液中天然气水合物形成速率具有明显差异。在相同的温度下,实验压力越高,天然气水合物越易于形成,反应越剧烈。采用定容压力搜索法,测定了在13-18 MPa时此2种水基钻井液与绿峡谷气形成水合物的相平衡数据,显示一种钻井液能够促进水合物的形成,另外一种钻井液对水合物形成有抑制作用。

In the drilling process,with the proper temperature and pressure conditions,the drilling fluid is easy to form gas hydrates,which can cause pipeline blockage and the fluid properties change. In this work influences of two water-based drilling fluids on the Green Canyon gas hydrates formation were investigated. The results show that hydrates can form easily in these two water-based drilling fluids under the experimental conditions,and the formation rate is different because of the drilling fluid composition. An isochoric pressure-search method was used for gas hydrate formation equilibrium data measurements at the pressure range of 13 - 18 MPa and the results show between these two drilling fluids one can promote and the other can inhibit gas hydrate formation.