稠油复合吞吐中不同注入剂对比实验研究

稠油油藏在我国石油资源中占有重要地位,目前主要工业化开采方式是蒸汽吞吐和SGD技术等,但采收率一般在20%左右,这样大量资源无法有效采出,目前许多稠油区块开始使用注蒸汽过程中加入CO2和降粘剂等实现复合吞吐。本文在优选降粘剂的基础上,以中原油田油藏为基础开展复合吞吐过程中不同注入剂的配比优化研究。首先自主研发水平井吞吐的物理模拟实验装置,优化油溶性降粘剂+CO2+氮气+蒸汽的优化配比设计。实验结果表明,对于超稠油(粘度大于50 000 m Pa·S)复合吞吐效果不理想,这类油藏不适合,对于粘度小于50 000 m Pa·S的稠油复合吞吐可以提高单独蒸汽吞吐效果,同时得到注入剂的组合方式和具体组合参数值,对实际油藏开发有重要指导意义。

Experimental Study on the Contrast of Different Injection Agents in Heavy Oil Compound Injection

Heavy oil reservoir plays an important role in petroleum resources in China. At present, the main way of industrial exploitation is steam stimulation and SGD technology, etc. But the recovery rate is about 20%,and a large number of resources cannot be effectively extracted. At present, CO2 and viscosity reducer are always used in the steam injection process in many heavy oil blocks. In this paper, based on choosing suitable viscosity reducing agent, taking Zhongyuan oilfield reservoir as a research objective, experimental study on the composite ratio of different injection agents was carried out. First of all, the physical simulation experiment device of horizontal well stimulation was developed. Design optimization of oil soluble viscosity reducer +CO2+ nitrogen + steam was carried out. Experimental results show that the effect is not ideal for super heavy oil (viscosity is more than 50 000 mPa·S), the compound injection is not suitable for this kind of reservoir. For heavy oil with viscosity less than 5 0000 mPa·S, the compound injection can improve the effect of steam injection alone. At the same time, the combination mode of the injection agents and the specific combination parameter values have been obtained, which has important guiding significance to the development of actual oil reservoir.