Improvement of shale gas reservoir based on plasma pulse shock and frequency resonance technology

• Published in: Journal of natural gas science and engineering 2020-08, Vol.80, p.103403, Article 103403
• Main Authors: Zheng, Shichao, Kang, Zhongjian, Cui, Minghui, Nie, Yunliang, Zhang, Anqi
• Format: Article
• Language: English
• Subjects: Frequency resonance; Plasma pulse shock; Porosity and permeability; Shale gas reservoir improvement
• ISSN: 1875-5100
• DOI: 10.1016/j.jngse.2020.103403

A shale gas reservoir improvement equipment applied to shale gas stimulation was developed. The device mainly includes ground control system, energy storage charging system, resonance frequency detection system, discharge switch and discharge electrode. The shale gas reservoir is improved by plasma pulse shock and frequency resonance technology. The electron density distribution at different time of the switch was simulated, and the waveform of single discharge and repetitive pulse discharge of the electrode were measured. It is shown that the electron density distribution at different time is consistent with Townsend discharge and streamer theory. And the frequency range of discharge electrode is about 0–60 Hz, meanwhile the stable discharge time is about 1 h. Furthermore, the resonance excitation can significantly improve the crack percentage and volume of shale samples calculated from porosity curve which is obtained through CT-Scan technology, also the permeability reveals an increasing trend in different directions. The results indicate that the present research might have potential application in the field of shale gas reservoir. •A shale gas reservoir improvement equipment was developed.•Simulation of discharge switch is consistent with Townsend and streamer theory.•The frequency range of discharge electrode is about 0–60 Hz.•The physical parameters of shale samples under resonance excitation get improvement.