特超稠油油藏热化学协同作用研究  

Study on thermochemistry synergies in extra heavy oil reservoirs

作　　者：罗宪波 LUO Xianbo(Tianjin Branch of CNOOC(China)Limited,Tianjin 300459,China)

机构地区：[1]中海石油(中国)有限公司天津分公司,天津300459

出　　处：《复杂油气藏》2024年第2期188-193,共6页Complex Hydrocarbon Reservoirs

基　　金：中海石油(中国)有限公司科研院所联合攻关课题“基于非稳态稳压耦合的海上大井距注蒸汽热采开发规律研究”。

摘　　要：渤海D油田属于典型的特稠油油藏,此类稠油在地层条件下流动性差,常规蒸汽吞吐开发效果较差,需要辅助化学增效来改善开发效果。通过一维高温驱替实验装置和高温高压微观驱替物理模拟实验装置,利用室内物模实验研究了蒸汽复合化学增效过程及热复合化学驱增效机理。研究发现:蒸汽复合化学驱能明显提高特稠油采收率,其增产机理体现在利用蒸汽热降黏,化学药剂辅助降低黏度,并通过调堵提高蒸汽利用率,蒸汽复合化学驱较单一蒸汽驱驱油效率提高幅度达到16%,蒸汽复合化学体系中降黏剂能溶解稠油中的胶质、沥青质,降黏率达70%,并大幅度降低屈服值改变稠油流变性,降低启动压力,利于特稠油在储层渗流;120℃条件下,蒸汽复合化学增效能将油水界面张力降低至10^(-5)mN/m水平,提高驱油效率;此外,泡沫还能对高渗层进行封堵,提高低渗层驱油效率15%。研究成果为海上特稠油的高效开发提供了理论指导。The D Oilfield of the Bohai Sea is a typical extra-heavy oil reservoir.This kind of heavy oil has poor fluidity under formation conditions,and the development effect of conventional steam huff and puff is poor.Auxiliary chemical synergism is needed to improve the development effect.Through a one-dimensional high-temperature displacement experimental device and a high-temperature and high-pressure micro-displacement physical simulation experimental device,indoor physical modeling experiments have been used to study the process of steam compound chemical synergism and thermal composite chemical enhancement mechanism.It is found that steam composite chemical flooding can significantly improve the recovery rate of extra heavy oil,and its mechanism of increasing production is reflected in the use of steam heat to reduce viscosity,the aid of chemical agents to reduce viscosity,and the improvement of steam utilization rate through plugging control.Compared with single steam flooding,the oil displacement efficiency of steam composite chemical flooding has increased by 16%.The viscosity-reducing agent in the steam composite chemical system can dissolve the gum and asphaltene in heavy oil,and the viscosity-reducing rate has reached 70%.The yield value is significantly reduced to change the rheology of heavy oil and reduce the starting pressure,which is conducive to the flow of extra-heavy oil in the reservoir.Under the condition of 120℃,the steam composite chemical synergism can reduce the oil-water interfacial tension to the level of 10^(-5)mN/m,which can improve the oil displacement efficiency.In addition,the foam can also seal the high-permeability layer and increase the oil displacement efficiency of the low-permeability layer by 15%.The research results provide theoretical guidance for developing offshore extra heavy oil efficiently.

关 键 词：海上特稠油 热复合化学 增效机理 降黏 封堵 

分 类 号：TE357.46[石油与天然气工程—油气田开发工程]