可降解纤维及其在老井暂堵酸压中的应用

Degradable Fiber and Its Application of Temporary Plugging Effect in Old Well Acid-Fracturing

哈萨克斯坦R油田是一开采20多年的老油田,油田单井射孔段数多、射孔段跨度大、层间及层内非均质性强,且70%的老井进行过酸压改造。为了改善老井产液剖面、提高储层动用程度、增加单井产量,暂堵转向技术成为改造裂缝性碳酸盐岩老油田的首选。根据对比分析,优选可降解纤维做为暂堵材料,并通过室内试验对纤维暂堵性能、降解性能、与酸液配伍性能等进行了评价。通过对可降解纤维性能的分析,给出了一些使用原则。2011年完成了第一口井的试验,施工显示,暂堵性纤维明显起到了暂堵转向的作用,且明显提高了单井产量;2012年完成的12口井也都达到了增产的目的,说明该工艺在老井改造中具有较好的应用前景。

Kazakhstan R oilfield is an old oilfield,which has been developed more than 20 years. For single well in this oilfield,there are many perforated layers,and the span of which is very large,and there exists heterogeneity either between different layers or during the same layer. Besides,more than 70 percent wells had been acid-fractured. In order to improve production profile,increase single well controlling area and production rate,temporary plugging technology becomes the best choice of stimulating carbonate reservoir. Based on comparative analysis,degradable fiber was chosen to be the optimized material,and through laboratory experiments,its plugging property,degradable property and compatibility are evaluated. According to the testing results,some using principles have been given.First test well was carried out in 2011,temporary plugging and diverting display was clearly observed,and finally production rate was increased obviously. Other twelve wells using the same technology were completed in 2012,and a satisfied result was gained,which means that this degradable fiber technology can get a better application effect in old well fracturing.