延长油田套损井化学封堵凝胶制备与应用

Preparation and application of chemical plugging gel for casing damage well in Yanchang Oilfield

针对延长油田套损井日益增多的问题,通过室内实验自制了适用于延长油田套损井的封堵凝胶体系,并优化了聚合物和交联剂,进一步通过填砂管驱替实验评价了凝胶封堵性能,并将凝胶体系进行了矿场套损井治理试验。结果表明,聚合物GX-ZSD-04具有良好的耐温和耐盐性能,优化的体系配方为:3000 mg/L聚合物GX-ZSD-04+200 mg/L交联剂XT-5-ZSD-01;制备的凝胶体系突破压力为5.02 MPa,突破压力梯度为18.59 MPa/m。优化的凝胶体系封堵后套损试验井含水率由100%降至81.01%,封堵效果良好。该研究可为延长油田和同类油田在套损井凝胶封堵技术的应用与推广提供依据。

In view of the increasing number of casing damage wells in Yanchang Oilfield,a plugging gel system suitable for casing damage wells in Yanchang Oilfield was homemade through laboratory experiments,and the polymer and crosslinking agent were optimized.The plugging performance of the gel was further evaluated through the sand filled pipe displacement experiment,and the gel system was tested for casing damage treatment in the field.The results showed that the polymer GX-ZSD-04 had good temperature and salt resistance,and the optimized formulation was as follows:3000 mg/L polymer GX-ZSD-04+200 mg/L crosslinker XT-5-ZSD-01;The breakthrough pressure of the prepared gel system was 5.02 MPa and the breakthrough pressure gradient was 18.59 MPa/m.After plugging with optimized gel system,the water content of casing loss test well was reduced from 100%to 81.01%,and the plugging effect was good.This study can provide a basis for the application and popularization of gel plug⁃ging technology in casing damage wells in Yanchang oilfield and similar oilfields.