渤海油田分级组合深部调剖技术

The Technology of Classified Combination of Deep Profile Control in the Bohai Oilfield

梁丹 吕鑫 蒋珊珊 梁守成 冯国智

Liang Dan Lü Xin Jiang Shanshan Liang Shoucheng Feng Guozhi

海洋石油高效开发国家重点实验室, 北京 100027; 中海油研究总院, 北京 100027

State Key Laboratory of Offshore Oil Exploitation, Beijing, 100027, China; CNOOC Research Center, Beijing, 100027, China

为了提高海上油田的开发效果,基于调剖决策的压力指数计算、调剖体系优选室内试验及调剖参数设计,进行了分级组合深部调剖技术研究.室内试验表明,采取先低强度(终冻强度0.05 MPa)后高强度(终冻强度0.07 MPa)连续相的顺序注入,比采取先高强度后低强度连续相的顺序注入时的采收率提高3.1百分点;采取先大粒径(初始粒径0.5~3.0 μm)分散相、后小粒径(初始粒径50~500 nm)分散相的顺序注入,比采取先小粒径分散相、后大粒径分散相的顺序注入时的采收率提高4.1百分点.膨胀后分散相颗粒与地层孔喉的最佳直径比为1时封堵率最高,且要求初始颗粒粒径小于1/7倍孔喉直径,膨胀后的最小粒径大于1/3倍孔喉直径.结合渤海油田的现场实例对该技术的应用效果进行分析,预测进行分级组合深部调剖后,含水率下降5.0%,2个井组增油3.4×104 m3以上.研究结果表明,在应用区块整体调剖决策参数确定目标调剖井的基础上,根据地层物性优选出合适的调剖体系,并对调剖体系进行优化组合设计,可以达到最佳的调剖效果.

Based on calculation of the pressure index for profile control decision-making, laboratory experiments for selecting profile control agents, and design of profile control parameters, the particle grading combination for deep profile control technology was studied. Laboratory experiments showed that injection of high-intensity(final frozen strength 0.07 MPa)profile control agent in continuous phase after injection of low-intensity(final frozen strength 0.05 MPa)agents provided a recovery efficiency 3.1% higher than that by reverse injection sequence, and injection of profile control agent with small particle size(initial particle size 0.5-3.0 μm)in dispersed phase after that with large particle size(initial particle size 50-500 nm)contributed a recovery efficiency 4.1% higher than that by reverse injection sequence. Highest plugging rate was obtained when the ratio of dispersed phase particle size after expansion to the size of pore throat inside formation was 1, and it was required that initial particle size was less than 1/7 of pore throat diameter, and minimum size of particles after expansion greater than 1/3 of pore throat diameter. The application of the technique in the Bohai Oilfield was analyzed, water cut declined by 5.0% and oil increased 3.4×104 m3 in two clusters of wells through particle size grading and combination for controlling deep profile. The research results showed that, if the target well is determined using the parameters for overall profile control, appropriate profile control agent is selected according to the reservoir property, optimized combination of profile control system is conducted, the best effect of profile control can be achieved.

中海石油(中国)有限公司综合科研项目“分级组合深部调剖技术研究”(编号:CNOOC-KJ 125 ZDXM 06 LTD 07 ZY 12)资助.

https://doi.org/10.11911/syztjs.201502018