, Hui Jin , Yechun Wang, Liejin GuoOil reservoirs contain significant amounts of water. Therefore, the role of water in the in situ hydrocarbon generation of medium- and low-maturity organic-rich shale cannot be ignored. In this study, a self-developed reaction system was used to simulate hydrocarbon generation under supercritical water in situ conversion, examining the influence of water-shale mass ratio changes on organic carbon migration and pore evolution. The results showed that higher water-shale mass ratios were conducive to the conversion of organic carbon in shale and the migration of organic carbon to gas-phase products. As the water-shale mass ratio increased, the proportion of carbon elements in carbon dioxide from organic sources gradually decreased, while that of carbon elements from inorganic sources gradually increased. Increasing the water-shale mass ratio from 0.5 to 5, the porosity and permeability of shale were greatly improved, with porosity increasing more than threefold and permeability more than fivefold.
1. Lewan, M. D. Water as a source of hydrogen and oxygen in petroleum formation by hydrous pyrolysis. Am. Chem. Soc., Div. Fuel Chem., 1992, 37, 1643−1649.
2. Deng, S., Wang, Z., Gao, Y., Gu, Q., Cui, X., Wang, H. Subcritical water extraction of bitumen from Huadian oil shale lumps. J. Anal. Appl. Pyrolysis, 2012, 98, 151−158.
https://doi.org/10.1016/j.jaap.2012.07.011
3. Akiya, N., Savage, P. E. Roles of water for chemical reactions in high-temperature water. Chem. Rev., 2002, 102(8), 2725−2750.
https://doi.org/10.1021/cr000668w
4. Bake, K. D., Pomerantz, A. E. Optical analysis of pyrolysis products of Green River oil shale. Energy Fuels, 2017, 31(12), 13345−13352.
https://doi.org/10.1021/acs.energyfuels.7b01020
5. Kang, Z., Zhao, Y., Yang, D. Review of oil shale in-situ conversion technology. Appl. Energy, 2020, 269, 115121.
https://doi.org/10.1016/j.apenergy.2020.115121
6. Tang, X., Li, S., Yue, C., He, J., Hou, J. Lumping kinetics of hydrodesulfurization and hydrodenitrogenation of the middle distillate from Chinese shale oil. Oil Shale, 2013, 30(4), 517−535.
http://dx.doi.org/10.3176/oil.2013.4.05
7. Hou, L., Ma, W., Luo, X., Liu, J. Characteristics and quantitative models for hydrocarbon generation-retention-production of shale under ICP conditions: example from the Chang 7 member in the Ordos Basin. Fuel, 2020, 279, 118497.
https://doi.org/10.1016/j.fuel.2020.118497
8. Xie, T., Zhao, Q., Jin, H., Wang, Y., Guo, L. Reaction kinetics study on hydro-carbon generation of medium- and low-maturity organic-rich shale in super-critical water. Energy Fuels, 2023, 37(18), 14192–14201.
https://doi.org/10.1021/acs.energyfuels.3c02494
9. Xie, T., Zhao, Q., Jin, H., Wang, Y., Guo, L. Experimental investigation on the organic carbon migration path and pore evolution during co-thermal hydrocarbon generation of low maturity organic-rich shale and supercritical water. Energy Fuels, 2022, 36(24), 15047–15054.
https://doi.org/10.1021/acs.energyfuels.2c02932
10. Xie, T., Zhao, Q., Dong, Y., Jin, H., Wang, Y., Guo, L. Experimental investigation on the hydrocarbon generation of low maturity organic-rich shale in supercritical water. Oil Shale, 2022, 39(3), 169–188.
https://doi.org/10.3176/oil.2022.3.02
11. Dong, Y., Zhao, Q., Jin, H., Miao, Y., Zhang, Y., Wang, X., Guo, L. Hydrogen donation of supercritical water in asphaltenes upgrading by deuterium tracing method. J. Supercrit. Fluids, 2024, 205, 106137.
https://doi.org/10.1016/j.supflu.2023.106137
12. Dutta, R. P., Mccaffrey, W. C., Gray, M. R., Muehlenbachs, K. Thermal cracking of Athabasca bitumen: influence of steam on reaction chemistry. Energy Fuels, 2000, 14(3), 671–676.
https://doi.org/10.1021/ef990223e
13. Gao, L., Liu, Y., Wen, L., Huang, W., Mu, X., Zong, B., Fan, H., Han, B. The effect of supercritical water on the hydroconversion of Tahe residue. AIChE J., 2010, 56(12), 3236–3242.
https://doi.org/10.1002/aic.12227
14. Hosseinpour, M., Akizuki, M., Oshima, Y., Soltani, M. Influence of formic acid and iron oxide nanoparticles on active hydrogenation of PAHs by hot compressed water. Isotope tracing study. Fuel, 2019, 254, 115675.
https://doi.org/10.1016/j.fuel.2019.115675
15. Hosseinpour, M., Fatemi, S., Ahmadi, S. J., Oshima, Y., Morimoto, M., Akizuki, M. Isotope tracing study on hydrogen donating capability of super-critical water assisted by formic acid to upgrade heavy oil: computer simulation vs. experiment. Fuel, 2018, 225, 161–173.
https://doi.org/10.1016/j.fuel.2018.03.098
16. Al-Muntaser, A. A., Varfolomeev, M. A., Suwaid, M. A., Saleh, M. M., Djimasbe, R., Yuan, C., Zairov, R. R., Ancheyta, J. Effect of decalin as hydrogen-donor for in-situ upgrading of heavy crude oil in presence of nickel-based catalyst. Fuel, 2022, 313, 122652.
https://doi.org/10.1016/j.fuel.2021.122652
17. Liang, X., Zhao, Q., Dong, Y., Guo, L., Jin, Z., Liu, Q. Experimental investigation on supercritical water gasification of organic-rich shale with low maturity for syngas production. Energy Fuels, 2021, 35(9), 7657–7665.
https://doi.org/10.1021/acs.energyfuels.0c04140
18. Wang, Z., Deng, S., Gu, Q., Cui, X., Zhang, Y., Wang, H. Subcritical water extraction of Huadian oil shale under isothermal condition and pyrolysate analysis. Energy Fuels, 2014, 28(4), 2305–2313.
https://doi.org/10.1021/ef5000062
19. Xie, T., Zhao, Q., Dong, Y., Jin, H., Wang, Y., Guo, L. Experimental investi-gation on hydrocarbon generation of organic-rich shale with low maturity in sub- and supercritical water. Geoenergy Sci. Eng., 2023, 223, 211553.
https://doi.org/10.1016/j.geoen.2023.211553
20. Xie, T., Zhao, Q., Jin, H., Wang, Y., Guo, L. Study on the influence of non-temperature factors on the migration path of organic carbon and evolution characteristics of pore permeability parameters of organic-rich shale under supercritical water in situ conversion. Oil Shale, 2024, 41(3), 189–207.
http://dx.doi.org/10.3176/oil.2024.3.03
