【作者】 钟满发；

【导师】 杜殿发；

【作者基本信息】 中国石油大学 ， 油气田开发工程， 2008， 硕士

【摘要】 由于在油层温度下脱气原油粘度大于5×104mPa·s,超稠油在油层中流动性很差甚至根本不能流动。采用常规蒸汽吞吐开发超稠油油藏存在含水上升率高,递减率大、最终原油采收率很低等问题。通过在注汽的同时注入一定量的油溶性降粘剂和二氧化碳来达到降低原油粘度、提高地层能量来改善蒸汽吞吐开发效果,提出一种针对超稠油油藏的新型开采技术即热三元复合吞吐技术。通过室内超稠油-二氧化碳混合体系高压物性试验以及在不同驱替介质(蒸汽、蒸汽+二氧化碳、蒸汽+二氧化碳+油溶性降粘剂)下的一维长岩心驱油实验,在分析作用机理、驱替效果的基础上,得出在注蒸汽的同时注入降粘剂和二氧化碳能够降低超稠油粘度,产生弹性能,从而提高驱油效率。根据物理模型的实验研究成果建立数值模型,在优化超稠油油藏常规蒸汽吞吐注汽参数的基础上,对热三元复合吞吐注采参数进行对比和优选,得到热三元复合吞吐最优方案。结果表明热三元复合吞吐技术比常规蒸汽吞吐技术提高2.37%的原油采收率。研究表明热三元复合吞吐技术能够较好地改善超稠油常规蒸汽吞吐效果,为我国开发超稠油油藏开辟一条新的途径。更多还原

【Abstract】 Ultra-heavy oil of which viscosity is more than 5×104mPa·s in reservoir has a poor mobility or even is unmovable. The conventional huff-puff method has many problems: higher water-cut escalating rate and decline rate, lower final oil recovery. So a new technology was suggested which was called thermal ternary combination huff-puff to exploit the ultra-heavy oil. This new technology was defined as that some oil-soluble viscosity reducers and CO2 were injected with steam to decrease the viscosity of crude oil and to enhance producing energy with the purpose of improving the effects of cyclic steam injection.Through the laboratory PVT test on ultra-heavy oil–CO2 mixed system and long core test using different displacing mediums (steam, steam+CO2, steam+CO2+ oil-soluble viscosity reducers), and based on the analysis of the mechanisms and the effects of displacement, it is concluded that injecting viscosity reducers and CO2 with steam can decrease viscosity of extra-heavy oil, produce elastic energy, so as to enhance the efficiency of oil displacement.According to the results of physical model experiment, a numerical model was built, on the basis of optimization of conventional steam stimulation parameters in the ultra-heavy oil reservoir, injection-production parameters were contrasted and optimized, then optimal case was obtained. The result showed that thermal ternary combination huff-puff improved 2.37% recovery comparing to conventional steam stimulation.The study indicated ternary combination huff-puff can improve the effect of conventional steam stimulation on ultra-heavy oil comparatively, it opened up a new way for the development of China’s ultra-heavy oil reservoir.更多还原