改善水泥浆堵剂悬浮性能的研究

Studies on Improving Particle Suspensibility of Cement Slurries for Water Plugging

水泥浆堵剂HS 2在特高含水期已广泛用于高渗透带和大孔道的封堵治理 ,以调整或改善注入水的吸水剖面。HS 2的主要成分为普通水泥 ,含有相应的一些添加剂 ,在注入过程中水泥颗粒受重力影响 ,易发生分层沉降 ,使水泥浆泵入性能变坏 ,不能有效地将水泥颗粒带入地层设计深度 ,在预定的位置水化固结。本文报道解决普通水泥浆悬浮性和凝固性的途径及得到的这两项性能良好的水泥浆堵剂 ,室内评价结果表明它的封堵效果良好 ,可用于有高渗透带和大孔道的注水井深部调剖。

To improve particle suspensibility of normal cement(No420) slurries following measures are undertaken: to choice fine particle size(40—80 μm) cement fractions; to viscosify the aqueous medium by a polymer(HPAM); to destruct the polymer film on the particles by a proper chemical and to promote the cement setting by an accelerator. The optimal formula for cement slurries is: 15% cement fraction of average particle size 60 μm, 0.4 HPAM, 1.5% film destructing agent, and 2.0% accelerator. In laboratory core experiments with the cement slurry, water plugging rates of 94.3% and 97.4% are observed. This improved cement slurry has been successfully used in highly permeable zone plugging operations at 10 water injection wells of Gudao Oil Fields.