CO 2驱和CO 2泡沫驱是提高采收率的有效技术。研究利用改进的高温高压可视化CO 2泡沫仪，针对不同表面活性剂，在不同CO 2相态、温度和压力条件下进行了CO 2泡沫性能测试实验。根据泡沫性能的不同评价指标，分析了影响CO 2泡沫性能的主要因素，及其不同实验条件和实验方法下测得的泡沫性能参数的相关性。结果表明，CO 2的相态(气态、液体和超临界状态)对产生泡沫的形态和泡沫性能影响很大。泡沫的起泡体积和稳定性主要受表面活性剂的类型和性能、温度和压力的影响。利用填砂管驱替实验装置，在不同压力、温度和渗透率条件下进行了CO 2泡沫流动实验，根据测试的阻力因子评价CO2泡沫的封堵剂流度控制能力，并与高温高压泡沫仪的测试参数进行对比和关联。实验结果表明，填砂管的渗透率对CO 2泡沫的封堵和流度有很大影响，渗透率越大，泡沫的封堵能力越强，有利于提高波及效率和降低CO2的流度。驱替实验所测得的CO2泡沫的流动阻力因子与泡沫仪测试的起泡体积和半衰期正相关，但泡沫的半衰期对泡沫的封堵和流度影响更大，即泡沫的稳定性是影响其在地层内流度控制作用的主要因素。%Injection of CO2 and CO2 foam is an effective technique for improving oil recovery. In this study, the performance of CO2 foaming agents (surfactants) was investigated using an improved high pressure and high temperature foam visualization device. CO2 foam was generated, and the foaming volume and half-life of foam were measured under high temperature and pressure. Experimental results show that foam can be formed and observed at various CO 2 states, i.e. gas, liquid and supercritical states. Surfactants and temperature have a significant effect on CO 2 foaming performance, and the effect of pressure on the foam stability is dependent on surfactant types. Moreover, the capability of CO2 foam for mobility control in porous media was evaluated by a resistance factor measured in flooding experiments using various sandpacks. Different evaluation parameters on CO2 foam performance revealed in the experiments were compared and correlated. The results show that the foaming volume and half-life of foam are proportional to the foam capability in mobility control, while foam stability (indicated by half-life) is more important for reducing its mobility at flowing conditions in porous media.
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