The current understanding of the potential for oil production from oil shale and the dynamic process of pyrolysis of organic matter remains unclear, thus hindering technological progress in this area. However, terahertz (THz) spectroscopy could offer new insights into the assessment of oil and gas resources.
Professor Kun Zhao and his teamBeijing Petroleum University recently reviewed the advances and challenges of THz spectroscopy for oil shale assessment.
The researchers summarized the applications of THz spectroscopy in characterizing anisotropy, organic distribution, kerogen fingerprint spectrum, oil yield, pyrolysis and the absorption of THz waves by oil shale.
They also proposed potential paths for the future of THz technology in oil shale development.
A new approach to kerogen analysis
Taking advantage of the characteristics of THz waves, researchers have developed a new concept of THz thermal analysis to rediscover the kerogen pyrolysis model. According to Professor Zhao, the most important discovery is that THz spectroscopy can simultaneously characterize the main oil generation zone and the natural gas zone, which is difficult to achieve with other standard methods.
The presence of a characteristic kerogen absorption peak in the THz range offers a new perspective for the study of kerogen on the micro and nanoscale. The researchers were also able to directly evaluate oil yield without pyrolysis, thanks to the strong dependence of THz anisotropic parameters on oil yield, thus avoiding environmental pollution.
Challenges and application perspectives
Despite the advances made in characterizing oil shale using THz waves, Professor Zhao emphasizes that research still lacks depth and that many challenges remain.
As for practical application, in situ conversion is an inevitable trend for large-scale commercial development of oil shale in the future. THz spectroscopy is expected to enable real-time monitoring of the oil shale downhole cracking process and oil and gas productivity.
Professor Zhao concludes that THz wave can become a valuable tool to overcome the problems related to oil shale mining, as long as some specific problems such as high-power light source, high-sensitivity detection, fast scanning and imaging, devices micro-nano THz and environmental adaptability.
For better understanding
1. What is terahertz (THz) spectroscopy?
Terahertz spectroscopy is an emerging assessment method in the area of oil and gas resources, which uses terahertz waves characterize various properties of the materials studied, namely oil shale.
2. The advantages of THz spectroscopy for oil shale assessment
THz spectroscopy can characterize the anisotropy, organic distribution, kerogen fingerprint spectrum, oil yield, pyrolysis process, and absorption of THz waves by oil shale.
The characteristic absorption peak of kerogen in the THz range provides a new perspective for the study of kerogen at the micro- and nanoscale.
4. THz spectroscopy allows evaluating oil yield without pyrolysis
The strong dependence of the THz anisotropic parameters on the oil yield makes it possible to directly evaluate the oil yield without resorting to pyrolysis, thus avoiding environmental pollution.
5. What are the challenges and application prospects of THz spectroscopy?
Challenges include finding high-power light sources, high-sensitivity detection, fast scanning and imaging, THz micro-nano devices, and environmental adaptability. The application prospects are in real-time monitoring of the downhole cracking process and oil and gas productivity.
|Emerging valuation method for oil and gas resources.
|Characterization of anisotropy, organic distribution, kerogen fingerprint spectrum, oil yield, pyrolysis process and THz wave absorption.
|New perspective for the study of kerogen on the micro and nanoscale thanks to the characteristic absorption peak.
|Direct assessment of oil yield without pyrolysis thanks to strong dependence on THz anisotropic parameters.
|Looking for high-power light sources, high-sensitivity detection, fast scanning and imaging, THz micro-nano devices, and environmental adaptability.
|Real-time monitoring of the downhole cracking process and oil and gas productivity.
|Inevitable trend towards large-scale commercial development of oil shale.
|THz waves make it possible to simultaneously characterize the main oil production zone and the natural gas zone.
|The results are published in Volume 2, Issue 4 of Energy Reviews in December 2023.
|THz spectroscopy could become a valuable tool for overcoming problems associated with oil shale exploration.
Main illustration caption: Researchers review the application of terahertz spectroscopy for the characterization and evaluation of oil shale. Credit: Kun Zhao of China University of Petroleum (Beijing)
References to the article are available in Volume 2, Issue 4 of Energy Reviews, published in December 2023. DOI: https://doi.org/10.1016/j.enrev.2023.100041 Author: Xuecong Liua, c, dKun ZhaoB C D,*Xinyang MiaoB C DHong Lei ZhanB C D
Associations: he hasCollege of Information Science and Technology, China Petroleum University; BCollege of New Energy and Materials, China Petroleum University; againstBeijing Key Laboratory of Oil and Gas Optical Detection Technology, China Petroleum University; dKey Laboratory of Oil and Gas Terahertz Spectroscopy and Photoelectric Detection, Federation of Petroleum and Chemical Industry, China Petroleum University