CO_2辅助超稠油蒸汽吞吐技术研究与应用

CARBON DIOXIDE ASSISTED ULTRA HEAVY OIL STEAM STIMULATION TECHNOLOGY RESEARCH AND APPLICATION

曙一区杜84块超稠油油藏主要采用蒸汽吞吐开采方式进行开发,油井经过高轮吞吐后,生产效果逐渐变差,周期产油、油汽比、日产能力等主要生产参数均降至较低水平。针对上述存在问题,进行CO_2辅助吞吐技术机理研究。通过研究,CO_2辅助蒸汽吞吐开采超稠油工艺技术机理主要有四点:1.注汽时提升地层压力,生产时有利于液体反排;2.增大蒸汽波及体积,均匀动用油藏。3.提升蒸汽热效率。4.气体溶于原油形成泡沫油,降低原油粘度。根据油藏特征优选实施井组,通过经验公式优化设计注汽量。实施结果表明,CO_2辅助超稠油蒸汽吞吐可以加快采油速度,提高采收率,是开采超稠油经济有效的工艺技术。

Shu1 area of Du 84 block,an super heavy oil reservoir by cyclic steam stimulation development wellafter the higher huff and puff,the production effect becomes worse. The main production parameters were re-duced to a low level,such as periodic oil production,oil steam ratio and daily production capacity. In view of theabove,we implement the research on the mechanism of stimulation of carbon dioxide. Through the research,there are four technology mechanisms of super heavy oil recovery by CO_2 gas assisted steam stimulation:first en-hance the formation pressure during steam injection,and reduce the formation pressure of the formation pressuredrop during production;second,increase the steam swept volume. Third,improve the steam thermal efficiency.Fourth,gas dissolved in the formation of crude oil,reducing the viscosity of crude oil. Optimizing the well groupby reservoir characteristics,the injection volume is optimized by empirical formula. The implementation effectshows that the auxiliary steam stimulation of carbon dioxide gas can accelerate the recovery of oil recovery,and itis an effective technology for producing super heavy oil.