胜利油田注空气二次采油技术评价研究

注空气技术已被成功应用于不同类型油藏以提高采收率。对注水困难的低渗透油藏来说,注空气取代注水进行二次采油以及注空气/空气泡沫进行三次采油都将受到越来越多的重视。针对注空气驱油机理和工艺特点,通过一系列实验和油藏数值模拟,研究低渗透油藏注空气提高采收率的机理及其应用。针对胜利油田低渗透轻质油藏目标区块,采用小型台架氧化反应器(SBR)进行原油氧化实验,并利用驱替装置进行氮气驱和空气驱的对比实验,评价了原油的氧化特性及空气驱的驱油效率,给出了原油-空气低温氧化动力学参数,为数值模拟提供基础数据。最后运用油藏数值模拟热采模型对注空气过程中氧化反应的热效应提高采收率进行了预测。

Air Injection EOR for Shengli Oilfield: Experimental and Numerical Simulation Studies

Air injection (AI) as an EOR technology has been applied in different types of reservoirs. For reservoirs with low permeability and hard water injectivity, it will be paid more and more attentions that air injection instead of water injection as a secondary oil recovery technology and air injection or air foam injection as a tertiary oil recovery technology. In this study, the mechanisms of air injection to enhance oil recovery and the application of this technology have been studied through a series of experiments and numerical reservoir simulation works in term of the air flooding mechanisms and the technology characteristics. Oxidation tests using small batch reactors and the contrast experiments of N2 flooding and air flooding by sand-pack model have been conducted for a target low permeability light oil reservoir in Shengli Oilfield. The oxidation properties of the oil and the oil displacement efficiency have been evaluated through the experiments. The low temperature oxidation kinetics parameters of oil-air have been obtained which provide basic data for the numerical simulation works. At last, reservoir simulation using a thermal model was carried out to predict the thermal effect in the oxidation process and enhanced oil recovery performance in the air injection process.