储层固相在化学驱替剂中物相变化的实验研究

EXPERIMENTAL STUDY ON SOLID CHANGE IN CHEMICAL FLOODING AGENTS

选择典型的储层粘土矿物钙蒙脱石、高岭石、伊利石、美国钙蒙脱石和新疆克拉玛依油田三采试验区——克二中区的S72 储层砂,在常温25 ℃下与克市黑液体系、华东黑液体系、聚合物溶液(0.18% 353OS)、碱-表面活性剂-聚合物体系(ASP)等驱替剂反应1 440 h。对反应前后固相物的X射线衍射分析表明钙蒙脱石首先发生阳离子交换生成钠蒙脱石,进而发生溶蚀;高岭石、伊利石和储层砂中的骨架矿物主要发生溶蚀和生成新矿物相。克市黑液体系对储层固相的溶蚀最强。单一聚合物溶液使美国钙蒙脱石发生晶格膨胀,形成均匀稳定体系,而在ASP体系中形成不均匀体系。

Selected typical clay minerals such as montmorillonite, kaolinite, illite, bentonite and S 7 2 reservoir sand from Xinjiang are reacted for 1 440 hours at 25℃ with such flooding agents as Xinjiang black liquid, Huadong black liquid, polymeric solution and alkaline surfactant polymer system (ASP). X ray diffraction analysis shows that, initially, the ion exchange of montmorillonite results in the transformation of Ca montmorillonite into Na montmorillonite and subsequently subjects to corrosion. Neomineralization and corrosion mainly occur in kaolinite, illite and other framework minerals. Mono polymer solution causes the lattice expansion of bentonite and forms a uniform and stable system. In ASP system, bentonite forms a non uniform system.