选用不同的陶粒支撑剂,进行碳酸盐岩加砂和酸蚀加砂支撑裂缝短期导流能力试验。结果表明:酸化导致岩板表面变得凹凸不平、疏松、软化,产生许多细小的矿物颗粒,使酸蚀加砂支撑裂缝的导流能力大幅下降;对于加砂酸压井,应注意控制作用在支撑剂层和酸蚀区地层上的有效闭合压力,使其小于支撑剂和酸蚀地层的强度,防止支撑剂的嵌入、破坏以及酸蚀区地层的变形,以免裂缝导流能力大幅度下降;在加砂酸压施工条件允许的情况下,尽量选用大粒径的支撑剂。
An experiment on short-term conductivity of sand-adding and acid ecthing sand-adding propping fractures was car- ried out with carbonate cores by selecting different eeramsite proppant. The experimental results show that the core surface is roughness, loose and soft after acidizing, which results in many fine mineral particles producing and conductivity of acid ecthing sand-adding propping fractures decreasing. For sand-adding acid-fracturing wells, the effective closure pressure must be carefully controlled lower than strength of proppant and acid ecthing formation to prevent proppant embed and destroy, for- mation deformation, to minimize conductivity damage. The bigger proppant size should be selected if the working conditions allow.