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Cantarell是位于墨西哥坎佩切湾的一个重要的复合型海上油田,也是世界产量第二的大油田。它由五个油田组成,主要的产层是形成于侏罗纪、白垩纪和古新纪下叶的多裂缝、多孔碳酸盐岩地层。基质酸化通常作为这些碳酸盐岩油层主要的增产措施,特别是这些成熟的复合体已经达到了它们的最高产量。对所有的酸化措施来说,处理成功的一个关键因素就是酸液在各个生产层之间的分配。因为大部分生产井是非均质的,并且产层的渗透率不同,所以即使是酸液的分配也是一项困难的工作。另外,各层的含水饱和度对酸液的分配有重要的影响。因为酸液是水溶液,在高含水饱和度的情况下会优先进入产层,在很多情况下都会导致产水量提高。高产水量就会带来各种各样的问题。本文给出了55口高渗透率油井(渗透率范围为1000～6000mD,1md=1.02×10-3μm2)在被一种基于缔合聚合物技术(APT)的新型酸转向剂酸化处理之后的结果。这种聚合物能够降低地层对水的渗透率,但对碳氢化合物的渗透率影响较小甚至无影响。给出了若干处理井的生产测井数据,这些数据能够说明在射孔段有很好的原油产量分配。另外,对用其他转向剂(如泡沫和就地交联酸)酸化处理的井也进行了生产测井,但效果稍差。
Cantarell is an important compound offshore oil field in Campeche Bay, Mexico, and the second largest oil field in the world. It consists of five oil fields, the main production layer is formed in the Jurassic, Cretaceous and Paleocene lower loess multi-fractured, porous carbonate rock formation. Matrix acidification is often the primary stimulus for these carbonate reservoirs, especially since these mature complexes have reached their highest yields. For all acidification measures, a key factor in the success of the process is the distribution of the acid between the various production layers. Because most of the production wells are heterogeneous and the permeability of the pay zone is different, even acid distribution can be a difficult task. In addition, the water saturation of each layer has an important effect on the acid distribution. Because acid is an aqueous solution, it will preferentially enter the pay zone in the case of high water saturation and in many cases will result in an increase in water production. High water yield brings a variety of problems. This paper presents the results of 55 high permeability wells (permeability range 1000-6000mD, 1md = 1.02x10-3μm2) after being acidified by a new acid diverter based on Associative Polymer Technology (APT) . This polymer reduces the formation’s permeability to water, but has little or no effect on the hydrocarbon permeability. Production well logs for several treatment wells are given and these data show that there is a good distribution of crude oil production at the perforation. In addition, production wells were also acid-treated with other diverting agents, such as foam and in-situ cross-linked acids, with somewhat less effect.