摘要
为了降低河水与长6地层水混合水回注长6地层时因结垢造成的伤害，通过离子含量、结垢量及垢型、混合水失钙率分析等，研究了陕北油田某采油厂河水和长6层产出水的混合性质；运用岩心流动实验评价了混合水对长6地层岩心的伤害。结果表明：长6地层水的矿化度为80000 mg/L以上，河水矿化度为120 0 mg/L左右； 30℃下，河水、长6地层水的体积比为6:4时，混合水的失钙率及结垢量最高，分别为9.5%和36 mg/L；处理过的混合水与长6地层水以体积比7:3混合后的失钙率及结垢量最低，分别为0.59%和 21.5 mg/L；经过处理的混合水悬浮含量、含油量分别由处理前的68 mg/L、115 mg/L降低到处理后的2.6 mg/L、3.7 mg/L，且注入体积为1～15 PV时，岩心伤害率为14.29%，低于20%。
Abstract
The mixed water properties of river water and Chang-6 layer produced-water(C-6W) in Shanbei Oil production plant was studied, including ion content, scale and scale type, calcium loss rate, respectively, in order to reduce the scale harm to Chang-6 layer from river water and C-6W. It was shown that the salinity of C-6W was above of 80000 mg/L, the river water salinity was about 1200 mg/L; when the volume ratio of C-6W to River water was 6:4, the highest calcium loss rate and amount of scale (9.5% and 36 mg/L, respectively) were achieved at the temperature of 30℃; when the mixed water was remixed with river water at volume ratio of 7:3, the lowest reservoir calcium loss rate and amount of scale (0.59% and 21.5 mg/L, respectively) were obtained. The amount of suspension content and oil content of the processed mixed water was decreased from 68 mg/L and 115 mg/L to 2.6 mg/L and 3.7 mg/L, respectively, which met the re-injection water quality standard, and a low core damage rate of 14.29%(<20%) could be found when the re-injection volume was 1-15 PV.
论文详情