Advances in characterization and evaluation of oil shale based on terahertz spectroscopy

The current understanding of the oil generation potential of oil shale and the dynamic process of organic matter pyrolysis is still unclear, leading to the relatively slow progress in its development technology. Due to the characteristics such as fingerprint property, low energy, penetration, and broadband, terahertz (THz) spectroscopy as an emerging evaluation method in the field of oil and gas resources has demonstrated research and application value in multiple aspects. “These include THz dating, THz exploration, crude oil identification, crude oil emulsion demulsification process, pattern transitions of oil-water two-phase flow, disaggregation of crude oil in a magnetic field, PM2.5 monitoring, and grading,” explains Professor Kun Zhao, who works at the Beijing Key Laboratory of Optical Detection Technology for Oil and Gas at the China University of Petroleum (Beijing), China.

To meet the requirements of new theories and methods for efficient utilization of oil shale resources, Prof. Zhao and his “oil and gas optics” team from China University of Petroleum (Beijing), China, recently reviewed the advances and challenges in THz spectroscopy for the evaluation of oil shale. Their findings were made available online on 16 August 2023 and will be published in Volume 2, Issue 4 of Energy Reviews in December 2023. In the review article, the team summarizes the applications of THz spectroscopy in characterizing anisotropy, organic distribution, fingerprint spectrum of kerogen, oil yield, pyrolysis process, and THz wave absorption of oil shale. In addition, they propose the potential pathway for THz technology, considering oil shale’s actual development in future.

Taking advantage of the features of THz wave, a new concept of thermal THz analysis was developed to rediscover the pyrolysis model of kerogen. “The most important discovery of THz wave exploration is that the main oil generation zone and natural gas zone can be characterized simultaneously using THz spectroscopy, which is difficult to achieve using other standard methods,” points out Prof. Zhao.

The characteristic absorption peak of kerogen in the THz range provides a new insight into the research of kerogen in the micro and nano scale. The researchers also realized direct evaluation of the oil yield without pyrolysis due to the strong dependence of the anisotropic THz parameters on the oil yield to avoid environmental pollution.

“Although the important progress of THz wave characterization of oil shale has been achieved, the research breadth and depth are still lacking, and many challenges need to be solved,” highlights Prof. Zhao. As for practical application, in situ conversion is an inevitable trend for large-scale commercial development of oil shale in the future. It is expected for THz spectroscopy to monitor the downhole cracking process of oil shale and productivity of oil and gas in real-time.

“THz wave is expected to become a sharp edge to overcome the bottleneck problem of oil shale exploitation after some specific problems are addressed, such as high-power light source, high sensitivity detection, fast scanning and imaging, micro-nano THz device, and strong environmental adaptability,” concludes Prof. Zhao.

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Reference

DOI: https://doi.org/10.1016/j.enrev.2023.100041

Authors: Xuecong Liu^a,c,d, Kun Zhao^b,c,d,*, Xinyang Miao^b,c,d, Honglei Zhan^b,c,d

Affiliations:            

^aCollege of Information Science and Technology, China University of Petroleum

^bCollege of New Energy and Materials, China University of Petroleum

^cBeijing Key Laboratory of Optical Detection Technology for Oil and Gas, China University of Petroleum

^dKey Laboratory of Oil and Gas Terahertz Spectroscopy and Photoelectric Detection, Petroleum and Chemical Industry Federation, China University of Petroleum

*Corresponding author email id: zhk@cup.edu.cn

About Professor Kun Zhao from China University of Petroleum (Beijing)

Dr. Kun Zhao currently works as a Professor at the Beijing Key Laboratory of Optical Detection Technology for Oil and Gas at the China University of Petroleum (Beijing), China. He received his B.S. degree in magnetic materials from Nanjing University, China, in 1992, M.S. degree in condensed matter physics from the Institute of Physics, Chinese Academy of Sciences, China, in 1994, and the Ph.D. degree in thin-film physics from The Chinese University of Hong Kong, China, in 2001. His research interests include oil and gas optics technology, mineral functional materials, and quantum exploration. He has published over 400 international journal papers and several book chapters.

About Energy Reviews

Energy Reviews is an international, interdisciplinary, high-quality, open-access academic journal in the field of energy, which is sponsored by Shenzhen University and published by the Elsevier publishing group. Energy Reviews invites high-quality reviews at the forefront of research in a broad range of topics covering not only materials, chemistry, and engineering, but also new energy devices, applications, methods, tools, theories, policy and management. The following areas will be prioritized, but not exclusively:

1. New theories, methods, and technologies for energy research

2. Interdisciplinary research of materials, physics, chemistry, and biology in energy

3. Low-carbon utilization of fossil fuel and CCUS

4. Advanced hydrogen, renewable energy, and energy storage technologies

5. Exploration and applications of novel energy conversion

6. Applications of AI, big data in energy

Website: https://www.sciencedirect.com/journal/energy-reviews