页岩气增产用脉冲放电冲击波装置研究

Research on a Shock Wave Device with Pulsed Discharge for Shale Gas Stimulation

黄昆 李欣阳 朱鑫磊 孟庆阳 曾凡辉

HUANG Kun LI Xinyang ZHU Xinlei MENG Qingyang ZENG Fanhui

清华四川能源互联网研究院, 四川成都 610213 西南石油大学石油与天然气工程学院, 四川成都 610500

Sichuan Energy Internet Research Institute, Tsinghua University, Chengdu, Sichuan, 610213, China Petroleum Engineering School, Southwest Petroleum University, Sichuan, Chengdu, 610500, China

为进一步推进脉冲放电冲击波技术在页岩气井增产中的应用，研制了可用于页岩气井井下作业的脉冲放电冲击波装置。该装置包括位于地面的电源系统和位于井下的储能、放电系统，其中井下部分封装在外径为102.0 mm的不锈钢外筒内，以保证有较好的绝缘性能和机械强度。该装置的设计最高电压和最大储能分别为10 kV和5 kJ，单次下井重复放电4 000次以上。根据现场特点和工程需求，对该装置的储能方式、负载电极、高压电容器等进行了研究设计，在地面进行了解堵除垢和岩样致裂调试试验，并在油井中开展了井下试验。地面调试试验发现，脉冲放电冲击波装置工作稳定性好，具有解堵疏通、致裂岩石的效果；井下试验结果表明，产液量和产油量相比施工前分别提高227%和197%，取得了较好的增产效果。研究认为，该装置工作稳定性好，在油井中具有很好的解堵疏通、致裂岩石的效果，也具备应用于页岩气井进行增产的可行性，但在页岩气井中具体效果如何，还有待于进一步研究。

In order to further promote the application of pulsed discharge shock wave technology in production stimulation of shale gas wells, a shock wave device with pulsed discharge that could be used for downhole operations in shale gas wells was designed and developed. The device includes a ground power system and downhole energy storage and discharge systems. For favorable insulation performance and mechanical strength, the downhole part was enclosed in a stainless steel outer cylinder with an diameter of 102.0 mm. With a design maximum voltage of 10 kV and a maximum energy storage of 5 kJ, the device can repeatedly discharge more than 4000 times in a single downhole trip. Further, its energy storage method, load electrodes, and high-voltage capacitor were designed according to field characteristics and engineering requirements. Unblocking and rock sample fracturing experiments were carried out on the ground, and a downhole test was conducted in a oil well. Ground debugging experiments showed that the pulsed discharge shock wave device possessed high working stability, with effects of unblocking and rock fracturing. The downhole test revealed that liquid and oil production increased by 227% and 197%, respectively. Compared with those before construction, a favorable effect of production increase was achieved. Studies indicated that the device had high working stability and were able to achieve the favorable effects of unblocking and rock fracturing in oil wells. Further, it is also feasible to be applied to shale gas wells for stimulation, although the specific effect in shale gas wells needs further research.

四川省省院省校科技合作研发重点项目“应用于油气增产的电脉冲酸化复合技术研究”（编号：2021YFSY0020）资助

https://doi.org/10.11911/syztjs.2022049