According to geological characteristics of high liquid content and high water content wells in Chaoyang Trench oil field .A new chemical water shutoff agent with strong strength and strong stability was selected through the determination of gelling strength ,gelling time ,stability time ,type and concentration of shutoff agents and additives .The optimum formula of water plugging (mass fraction) is as follows :0 .7% HPAM + 2% Ca-Ls + 0 .3% organic chromium + 0 .15% NaHCO3 + 0 .005%thiourea .The viscosity in 24 h is less than 2000 mPa · s ,the gelling time is more than 48 h ,the gelling max viscosity is more than 20000 mPa · s , and the viscosity reservation in 30 days is more than 80% .According to the cores of different permeability ,the water plugging rate of plugging agent is more than 80% ,and the plugging oil rate is less than 20% ,which has good selectivity .It has been used on 3 wells in Chaoyang Trench oil field in 2016 .The increase production of cumulative oil is 2225 .3 t ,and the cut of cumulative water is 11631 .2 t ,which has good sealing performance .%针对朝阳沟油田高液量高含水井的地质特点,通过测定体系成胶强度 、成胶时间 、稳定时间,优选堵水剂的主剂类型 、浓度及添加剂的类型和浓度,优选出强度较大且稳定性强的新型化学堵水剂配方.所研制的最佳选择性堵水配方(质量分数)为:0.7%HPAM+2%Ca-Ls+0.3%有机铬+0.15%NaHCO3+0.005%硫脲.24 h黏度小于2000 mPa·s,成胶时间大于48 h,成胶最大黏度大于20000 mPa·s,且30 d黏度保留率大于80%.对不同渗透率的岩芯,堵水剂的堵水率大于80%,堵油率小于20%,具有良好的选择性.在朝阳沟油田现场施工3口井,累计增油2225.3 t,累计降水量11631.2 t,具有较好的封堵性.
展开▼
