Low-to-medium maturity lacustrine shale oil resource and in-situ conversion process technology: Recent advances and challenges

Abstract

Low-to-medium maturity lacustrine shale oil resources have enormous potential and are projected to play a crucial role in the massive scale-up of crude oil production in China in the near future. The in-situ conversion process is currently the only effective means of utilizing this resource. Nevertheless, significant scientific challenges and technological bottlenecks still exist. Under this circumstance, the National Natural Science Foundation of China approved an integrated project of the Enterprise Innovation and Development Joint Fund titled “The Mechanism of Low-to-medium Maturity Lacustrine Shale Oil Resource Formation and its in-situ Conversion and Exploitation”. This project aims to systematically investigate the entire process of in-situ conversion for low-to-medium maturity shale oil resources and lay a solid scientific and technological foundation for advancing the smooth implementation of on-site pilot trials. This paper presents the latest progress in this field and summarizes the existing scientific and technological challenges that need to be addressed. With the foundational support of the above project, our research team has made significant progress in several fields, including the formation mechanisms of organic matter superrich shale, low-to-medium maturity shale oil enrichment area evaluation, heat and mass transfer dynamics, coupled fluid field and hydrocarbon expulsion efficiency, exploitation methods, among others. Despite these theoretical advances, several major challenges were identified, which help to further focus on the critical scientific issues, determine the in-situ conversion technique-developing direction, and formulate a feasible implementation plan for future resource utilization.

Document Type: Perspective

Cited as: Zhao, W., Guan, M., Liu, W., Bian, C., Li, Y., Wang, X., Xu, R. Low-to-medium maturity lacustrine shale oil resource and in-situ conversion process technology: Recent advances and challenges. Advances in Geo-Energy Research, 2024, 12(2): 81-88. https://doi.org/10.46690/ager.2024.05.01

References

Baled, H., Enick, R. M., Wu, Y., et al. Prediction of hydrocarbon densities at extreme conditions using volume-translated SRK and PR equations of state fit to high temperature, high pressure PVT data. Fluid Phase Equilibr, 2012, 317: 65-76.

Guo, Q., Hou, L., Wang, J., et al. An evaluation method of resource potential of in-situ converted shale oil and its application. Acta Petrolei Sinica, 2022, 12(43): 1750-1757. (in Chinese)

Guo, W., Shui, H., Liu, Z., et al. Reliability analysis of elastic graphite packer in heat injection well during oil shale in-situ conversion. Advances in Geo-Energy Research, 2023, 7(1): 28-38.

Hu, T., Jiang, F., Pang, X., et al. Identification and evaluation of shale oil micro-migration and its petroleum geological significance. Petroleum Exploration and Development, 2024, 51(1): 127-140.

Jarvie, D., Claxton, B., Henk, F., et al. Oil and shale gas from the Barnett Shale, Ft. Worth Basin, Texas. AAPG National Conversion, Denver, Colorado, 3-6 June, 2001.

Jin, J., Sun, J., Lv, K., et al. Catalytic pyrolysis of oil shale using tailored Cu@zeolite catalyst and molecular dynamic simulation. Energy, 2023, 278: 127858.

Kang, Z., Zhao, Y., Yang, D., et al. Review of oil shale in-situ conversion technology. Applied Energy, 2020, 269: 115121.

Li, C., Jin, Z., Zhang, L., et al. Advancing the application of sub-and supercritical water in the in-situ conversion of immature and low-maturity shale. Fuel, 2024, 359: 129891.

Liu, Q., Li, P., Jiang, L., et al. Distinctive volcanic ash-rich lacustrine shale deposition related to chemical weathering intensity during the Late Triassic: Evidence from lithium contents and isotopes. Science Advance, 2024, 10(11): eadi6594.

Liu, W., Liu, M., Yang, T., et al. Organic matter accumulations in the Santonian-Campanian (Upper Cretaceous) lacustrine Nenjiang shale (K2n) in the Songliao Basin, NE China: Terrestrial responses to OAE3? International Journal of Coal Geology, 2022, 260: 104069.

Liu, Y., Yao, C., Liu, B., et al. A neural network-based method for predicting the hydrocarbon expulsion potential of shale heat injection in-situ mining. CN202310575426.9, 2023.

Lu, H., Xu, Y., Duan, C., et al. Experimental Study on Capillary Imbibition of Shale Oil in Nanochannels. Energy & Fuels, 2022, 36(10): 5267-5275.

Lu, T., Xu, R., Zhou, B., et al. Improved method for measuring the permeability of nanoporous material and its application to shale matrix with ultra-low permeability. Materials, 2019, 12(9): 1567.

National Energy Administration (NEA). Top ten iconic achievements in national oil and gas exploration and development in 2023. 9 January, 2024.

Ryan, R., Fowler, T., Beer, G., et al. Shell’s in situ conversion process - From laboratory to field pilots, A Solution to the Liquid Fuel Dilemma, edited by Ogunsola American Chemical Society Symposium, New York, pp. 161-183, 2010.

Sun, Y., Guo, W., Li, Q., et al. Current status and prospects of oil shale in-situ conversion technology in China. Petroleum Science Bulletin, 2023, 8(4): 475-490. (in Chinese)

Vandenbroucke, M., Largeau, C. Kerogen origin, evolution and structure. Organic Geochemistry, 2007, 38(5): 719-833.

Wang, X., Li, J., Jiang, W., et al. Characteristics, current exploration practices, and prospects of continental shale oil in China. Advances in Geo-Energy Research, 2022, 6(6): 454-459.

Zhang, J., Wu, Y., Wang, C., et al. Experimental study on improvement mechanism of electric heating-assisted cyclic steam stimulation of horizontal well. Applied Sciences, 2022, 12(21): 11294.

Zhao, J., Wang, L., Liu, S., et al. Numerical simulation and thermo-hydro-mechanical coupling model of in situ mining of low-mature organic-rich shale by convection heating. Advances in Geo-Energy Research, 2022, 6(6): 502-514.

Zhao, W., Bian, C., Li, Y., et al. Organic matter transformation ratio, hydrocarbon expulsion efficiency and shale oil enrichment type in Chang 73 shale of Upper Triassic Yanchang Formation in Ordos Basin, NW China. Petroleum Exploration and Development, 2023a, 50(1): 12-26.

Zhao, W., Bian, C., Pu, X., et al. Enrichment and flow characteristics of shale oil in typical salinized lake basins in China and its significance for “sweet spot” evaluation. Journal of China University of Petroleum (Edition of Natural Science), 2023b, 47(5): 25-37. (in Chinese)

Zhao, W., Hu, S., Hou, L., et al. Connotation and strategic role of in-situ conversion processing of shale oil underground in the onshore China. Petroleum Exploration and Development, 2018, 45(4): 563-572.

Zhao, W., Zhao, Y., Li, G., et al. Scientific problems and key technologies of enrichment and in-situ transformation of low-to-mid matured shale oil in continental facies. Bulletin of National Natural Science Foundation of China, 2023c, 37(2): 276-284. (in Chinese)