孤岛油田中一区聚合物驱油井见效特征及影响因素

The response and effecting factors of polymer flooding in Unit 1 of Central Gudao oil field.

孤岛油田进行了聚合物驱试验 ,取得了明显的降水增油效果 ,注聚区内油井单井见效特点不同 ,按单井含水的变化划分为 4种类型 :“U”字型 ,单层生产 ,油层厚度较薄 ,含油饱和度高 ,具有含水下降幅度较大、见效时间长、累计增油量高、见聚较晚等特点 ;“V”字型井 ,多出现在油层厚度大 ,油层层内、层间非均质性强的区域 ,其含水下降幅度较小 ,见聚早 ,且大多见效同时见聚 ;“W”字型井 ,多为边角井 ,注采关系不稳定 ,含水下降幅度小 ,增油量较差 ;不见效型 ,受水驱干扰大 ,未见增油降水效果。每种类型的影响因素不同 ,主要影响因素是储集层性质、剩余油饱和度、注采关系等。图 1表 1参 2 (蔡燕杰摘 )

The effect of decreasing water cut and increasing oil production is obtained by polymer flooding test in Gudao oil field. There are four kinds of response of oil wells in polymer flooding area with different water cuts of single wells. The first is a well with water cut curve of “U” type, which is producing oil from a single thin oil-bearing formation with high oil saturation, decreasing water cut by a big margin, long-term effecting and increasing high production. The second is a “U” type well which has a thick oil-bearing formation with strong heterogeneity in inner or inter-bed and decreases water cut by a small margin. The third is a “W” type well, which is located at the edge of injection area,with non-balanced injection and production, and decreases water cut by a small scale, but increases production little. The fourth is an invalid well which is disturbed by water flooding with no effect of increasing production. Factors effecting every type well are different, which are reservoir property, remaining oil saturation, relation of injection and production, and so on.