中深层超稠油油藏SAGD开发热效率分析及提升对策

Analysis on the Thermal Efficiency of SAGD Development in Mid-deep Super Heavy Oil Reservoirs

针对目前中深层超稠油油藏SAGD(蒸汽辅助重力泄油)开发中热能消耗大、热利用率低的问题,参考辽河油田杜84块馆陶油层SAGD实际生产数据,对SAGD开发各阶段热损失原因和影响因素进行了分析,计算了开发全过程各阶段的热损失,并提出了热效率提升对策。结果表明:SAGD开发全过程的热损失包含注汽锅炉热损失、汽水分离器热损失、注汽管线热损失、注汽井筒热损失、地层吸热、生产井筒热损失6个部分;热损失主要集中在注汽锅炉、汽水分离器、注汽管线及注汽井筒,热损失比例达到了34.8%,地层吸热比例只有36.0%。针对主要热损失阶段提出了提高热效率的对策,现场实施后综合热效率提高了17.0个百分点。该研究可为改善中深层超稠油油藏SAGD开发效果及经济性提供技术参考。

In view of the problems of high heat consumption and low heat utilization rate in SAGD(steam assisted gravity drainage)development of med-deep super heavy oil reservoirs,the causes and influencing factors of heat loss in each stage of SAGD development were analyzed with reference to the actual SAGD production data of Guantao formation reservoir of Block Du 84 of Liaohe Oilfield,and countermeasures to improve the thermal efficiency were put forward.The results showed that the heat loss in the whole SAGD development included the heat loss of steam injection boiler,the heat loss of steam-water separator,the heat loss of steam injection pipe,the heat loss of steam injection wellbore,the formation heat absorption,and the heat loss of production wellbore;the heat loss mainly occurred in the steam injection boiler,steam-water separator,steam injection pipeline and steam injection wellbore;the heat loss ratio reached 34.8%,and the formation heat absorption ratio was only 36.0%.Countermeasures to improve thermal efficiency were put forward for the main heat loss stage and implemented on site,and the comprehensive thermal efficiency was increased by 17.0 percentage points.This study provides technical reference for improving the development effectiveness and economical efficiency of SAGD in med-deep super-heavy oil reservoirs.