超临界二氧化碳在非常规油气藏开采中的应用研究

Application of Supercritical Carbon Dioxide in Unconventional Oil and Gas Reservoir

超临界二氧化碳具有接近于气体的低黏度和高扩散系数,又具有接近于液体的高密度,这些性质引起了国内外石油行业的广泛关注,并将其引入油气藏开发。研究结果显示,超临界二氧化碳非常适合应用在非常规油气藏的开采作业中。我国的非常规油气藏储量丰富,但采收率普遍较低,将超临界二氧化碳引入非常规油气藏的开发很有必要。本文分析了超临界二氧化碳在非常规油气藏开采中的钻井、压裂、驱油及除垢洗井等作业过程中的技术原理和特点,认为,超临界二氧化碳弥补了水基钻井液或压裂液的不足,提高了效率,减少了污染,适用性好,并总结了超临界二氧化碳在非常规油气藏中的未来发展和总体优势。

Supercritical carbon dioxide had a low viscosity and high diffusion coefficient close to that of gas,and had a high density close to liquid,these properties caused widespread concern in the domestic and international oil industry and introduced it into the development of oil and gas reservoirs.Researeh results showed that supercritical carbon dioxide was very suitable for mining operations in unconventional oil and gas reservoirs.China’s unconventional oil and gas reservoirs were abundant,but the recovery rate was generally low.It was necessary to introduce supercritical carbon dioxide into the development of unconventional oil and gas reservoirs.This paper explaied the physical properties of carbon dioxide first,then analyzed the technical principles and features of supercritical carbon dioxide application to drilling,fracturing,oil displacement,removing impurity and well washing operations.It was believed that supercritical carbon dioxide compensates for the lack of water-based drilling fluids or fracturing fluids,increased efficiency,reduced pollution and had a good applicability.Finally,the future development and overall advantages of supercritical carbon dioxide in unconventional oil and gas reservoirs was summarized.