旅大27-2油田稠油油藏流体流动性影响因素

旅大27-2油田开发已经进入到蒸汽吞吐中后期,目前油田含水上升快,蒸汽吞吐开发效果变差。为了更好地对旅大27-2油田进行储量评价以和开发动用。详细研究了稠油族组成、温度、油水乳化、压力、N_2溶解及降黏剂对旅大27-2油田稠油黏度的影响,然后通过流动性实验证实了稠油在储层中的流动性主要受到黏度的影响,明确了温度、油水乳化和降黏剂的使用是影响稠油黏度的主要因素。当温度从50℃升高到100℃时,旅大27-2油田稠油油样黏度从3 665 mPa·s降低到172 mPa·s,降低了95.31%;50℃时,70%含水原油黏度为不含水原油黏度的21.1倍;50℃、降黏剂含量为1.0%时,降黏率为94%。有效地避免或者减弱油水乳化形成油包水乳状液,是有效提高油田开发效果的重要途径。

Study on Factors Affecting the Fluidity of Heavy Oil Reservoirs in LD27-2 Oilfield

The development of LD 27-2 oilfield has entered the middle and late stage of steam stimulation. At present, the water content of the oilfield has risen rapidly, and the development effect of steam stimulation has deteriorated. In order to better carry out the reserve evaluation and development of the LD 27-2 oilfield. In this paper, the effects of heavy oil composition, temperature, oil-water emulsification, pressure, N2 dissolution and viscosity reducer on the viscosity of heavy oil in LD 27-2 oilfield were studied in detail. Then through the fluidity experiment, it is confirmed that the fluidity of the heavy oil in the reservoir is mainly affected by the viscosity, and it is clear that the temperature, the oil-water emulsification and the use of the viscosity reducer are the main factors affecting the viscosity of the heavy oil. When the temperature is raised from 50 °C to 100 °C, the viscosity of the heavy oil sample of the LD 27-2 oilfield is reduced from 3665 mPa?s to 172 mPa?s, which is reduced by 95.31%. At 50 °C, the viscosity of the 70% water content crude oil is 21.1 times the viscosity of the dehydrated crude oil; when the temperature was 50 °C and the viscosity reducer content was 1.0%, the viscosity reduction rate was 94%. Effectively avoiding or weakening the emulsification of oil-water to form a water-in-oil emulsion is an important way to effectively improve the development of oilfields.