【作者】 胥晓伟；

【导师】 李兆敏；

【作者基本信息】 中国石油大学 ， 油气田开发工程， 2009， 硕士

【摘要】 二次采油技术是目前我国各主力油田进入开发后期提高采收率的重要方法之一,但由于受储层非均质性的影响,二次采油后油层中仍剩余40%-50%左右的原油未被采出,如何进一步提高采收率以保证油田可持续发展是亟待解决的问题。为了提高波及系数,本文提出进行冻胶泡沫调剖,冻胶泡沫调剖技术是非均质油藏开发中后期提高采收率的有效的新途径,近年来也进行了一些研究,但在泡沫渗流机理、影响因素分析以及适应性评价方面还有待深入研究,是一种处于新兴发展阶段的三次采油技术。因此,有必要对冻胶泡沫进行详细的研究。本文将起泡剂的起泡体积和半衰期作为评价指标,通过室内实验,探讨了起泡剂浓度、聚合物浓度、矿化度、温度等各因素对泡沫体系的发泡特性的影响因素,并筛选出了适合油田实际地层条件的起泡剂。分析了冻胶的分类和影响冻胶性能的因素,通过室内试验,对四种交联剂进行评价筛选。筛选出的YG103成冻时间达到四天,成冻强度达到D级。采用物理模型研究了泡沫在多孔介质中的渗流规律,分析了气液比、渗透率等因素对冻胶泡沫渗流规律的影响。随着气液比的增大,冻胶泡沫在多孔介质中的突破压力逐渐减小,但气液比在1以下时,其突破压力梯度仍大于8MPa/m。在一定的气液比和注入速度下,冻胶泡沫在多孔介质中的突破压力随着渗透率的增大而减小。通过模拟不同渗透率级差的非均质地层,进行了冻胶泡沫驱的实验研究,分析对比了不同注入方式下冻胶泡沫对地层的封堵影响,液气分段注入的方式能够起到很好的调剖作用,高渗岩心和低渗岩心的分流量出现了反转,优选注入方式后,分析了各驱替阶段高低渗透层中的产液量变化规律,分析了渗透率级差对冻胶泡沫在非均质储层中流度的影响。更多还原

【Abstract】 Secondary recovery has been an important enhanced oil recovery method adopted at the later stage of oilfield development in China. However, due to the effect of reservoir heterogeneity,there is still about 40%-50% remaining oil kept in oil-bearing formation after polymer flooding, and how to further enhance recovery factor and keep the oil-field sustained development has become the focus of research at present. For enhance the sweep efficiency ,this paper develops the jel foam profile control technology, and the jel foam profile control technology is an new effective improved oil recovery method for heterogeneous reservior at the later stage of development, and a series of studies has been done in recent years. But it is at development stage and needs deep study in mechanisms of foam flow in porous media, influential factor and applicability. Wherefore, it is very necessary to further study the jel foam flow in heterogeneous reservoir and the effect of jel foam flooding.Based on foamer’s foaming ability and stability, through laboratory experiment, several foamers used in oil field were evaluated through experiment, and affecting factors of foaming ability and stability is analysed. Based on gelation time and gelation intensity, through laboratory experiment, 4 crosslinkers were evaluated and one selected which can cross-link in 4 days and the hardness can reach D degree.Through physical model, the effects of gas-liquid ratio and permeability on jel foam flow law in porous media were studied systematically. With the gas-liquid ratio increasing, the jel foam breakthrough pressure in porous media decrease but still can be more than 8Mp/m when the gas-liquid ratio under 1:1. Under certain gas-liquid ratio and injection speed, the jel foam breakthrough pressure in porous media decrease with the permeability increasing.Through simulating heterogeneous reservoir with different permeability contrast, the jel foam profile control technology is proceed. we compared two injection system and then the effect on mobility regulatory of jel foam in heterogeneous reservoir caused by permeability contrast is analysed.更多还原