转向重复压裂工艺技术在低渗油田老井改造中的应用——以南泥湾油田为例

Application of Repeated Fracturing in Reforming Old Wells of Low Permeability Oilfields-Taking Nanniwan Oilfield as an example

低渗透油田经过初次压裂后单井产量逐渐降低,须依靠重复压裂来提高产量。在老井常规重复压裂过程中,常常只是重新压开原缝,而原有人工裂缝附近产层的生产潜能越来越小,增产效果不明显。为了提高老井重复压裂效果,在低渗透油田-南泥湾油田,油井重复压裂时采用了裂缝转向压裂工艺技术,使裂缝转向,压开新缝,更大限度沟通、改造剩余油富集区和动用程度低甚至未动用的储层。2008年通过对40口生产井的现场应用取得了较好的效果,为同类油藏的老井改造提供了可借鉴的经验。

Abstrac：The production of single well in low permeability oilfields decreases gradually after the initial fracturing.So it has to rely on repeated fracturing to increase production.In the process of routine repeating fracturing of old well,we usually re-open the original fractures again,while the potential development of the reservoir around the original fractures becomes less and less,and the effect of enhancing productivity decreases year by year.In order to improve the effect of repeated fracturing of old wells,we used the technology that was called turnaround refracturing,which could force the cracks to turn,bring pressure to open a new seam,communicate,and transform the remaining oil-rich area and the low-level use even unused reservoir to a greater extent in low permeability oil fields such ans Nanniwan oil field.In 2008,we achieved good results through the onsite applications of 40 producting wells,which provided learned experience for the transformation of old wells of the saam reservoir.