抗高温聚合物降滤失剂PFL-L的研制与应用

为使抗高温钻井液具有良好的流变性及高温高压滤失量,防止高温稠化,采用氧化-还原引发聚合反应,合成了一种低相对分子质量的抗高温聚合物降滤失剂PFL-L,进行了红外光谱和热重分析;采用凝胶渗透法测定了产物相对分子质量,评价了高温高盐情况下聚合物降滤失性能及配伍性。评价结果表明,PFL-L热稳定性好,产物分子量具有多分散性,适用于超深井钻井液处理剂,高温高盐条件下在显著降低钻井液滤失量的同时,可很好地控制钻井液高温下的黏度,抗温220℃,抗NaCl可达36%。该降滤失剂在徐闻X-3井进行了现场应用,应用结果证明,由PFL-L等处理剂形成的超高温钻井液热稳定性好,确保了徐闻X-3井三开长裸眼井段的顺利钻进,完钻井深6 010 m,取得了良好的应用效果,满足了安全高效钻井需求。 

Development and Application of an High Temperature Resistant Polymer PFL-L as Fluid Loss Additive

To prevent high temperature thickening and maintain good HTHP fluid loss and rheological property of high temperature resistant drilling fluids,a low molecular weight polymer fluid loss additive PFL-L was polymerized by oxidation/reduction reaction,and was analyzed by infrared spectrum and thermo gravimetric analysis.Its molecular weight was tested by gel permeation chromatography,the fluid loss and compatibility in drilling fluid were also evaluated under high temperature and high salinity.Test results show that PFL-L has good thermal stability and polydispersity of molecular weight,is suitable for drilling fluid in ultra-deep well as an additive.PFL-L can reduce fluid loss and control viscosity significantly at high temperature and high salinity,the heat resistance up to 220 ℃,salinity tolerance to saturation.It was applied in Well Xuwen X-3 which is an important exploratory well of Sinopec.Its field application shows that the drilling fluid has good high temperature stability,and met the demands of long open hole that drilled in the third spud to the total depth of 6 010 m.PFL-L,as an ultra-deep well drilling fluid filtrate reducer,it can also meet the demand of drilling safely efficiently in deep and ultra-deep wells.