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注气开发技术在世界上的应用越来越广泛,它成为提高注气开发驱油效率的推动力。此研究加深了对地层中气体流动性的认识并研究了流动控制试剂的经济性。本文描述了岩心驱替实验装置中油藏条件下泡沫降低气体流动性的情况。在此项目中泡沫的特性和吸附性是建立表面活性剂模型所必需的二个参数。研究使用的表面活性剂为工业用表面活性剂,使用的气体为氮气,实验的温度和压力均模拟地层温度和压力,实验温度为40℃,压力为10·34MPa,岩心为印第安纳石灰岩。表面活性剂的浓度、流量和泡沫质量均是实验的参数。在气体流量一定的情况下,当泡沫的质量低于其临界值(fg*)时,气体流动性随着泡沫质量的增加略有减少;当泡沫的质量大于其临界值(fg*)时,气体流动性随着泡沫质量的增大而增大。随着表面活性剂浓度的增加,气体的流动性减弱。比较表面活性剂+气体和水+气体的注入,前者的流动性低得多,并且达到稳定状态需要更多的时间。甚至在注入表面活性剂+气体前,在岩心中注入表面活性剂前置段塞也是如此。
Gas injection development technology is more and more widely used in the world and it has become a driving force for improving the efficiency of gas injection in developing displacement. This study deepens the understanding of gas flow in the formation and studies the economics of flow control reagents. This paper describes the foam reduction of gas flow under reservoir conditions in a core flood experiment. Foam properties and sorption in this project are two of the necessary parameters for establishing a surfactant model. The surfactant used in the study was industrial surfactant, and the gas used was nitrogen. The experimental temperature and pressure all simulated formation temperature and pressure. The experimental temperature was 40 ℃, the pressure was 10 · 34MPa, and the core was Indiana limestone. Surfactant concentration, flow rate, and foam quality are all experimental parameters. When the mass of foam is lower than its critical value (fg *), the gas flowability decreases slightly with the increase of foam mass under certain gas flow rate. When the mass of foam exceeds the critical value (fg *), Gas flow increases with increasing foam quality. As the surfactant concentration increases, the fluidity of the gas decreases. In comparison to injection of surfactant + gas and water + gas, the former has much lower fluidity and requires more time to reach a steady state. The same is true of injecting the surfactant pre-slug into the core, even before injecting the surfactant + gas.