Keju Yan, Qingwang Yuan. Bob L. Herd Department of Petroleum Engineering
To address the escalating demands for decarbonization within the petroleum industry, a pioneering technology known as in-situ hydrogen (H2) production via electromagnetic-assisted catalytic heating has recently been proposed for extracting clean H2 directly from petroleum reservoirs. This study explores H2 generation from hydrocarbon/water reactions in the presence of natural rock powders under electromagnetic irradiation. Real-time data on temperature profiles of rock samples, gas production, and concentrations of generated gases are monitored and recorded. Thermal Runaway (TR) phenomena are observed in both sandstone and shale rocks, occurring at 568°C for sandstone and 253°C for shale. Remarkably, upon TR occurrence, the post-TR sample can be efficiently reheated up to 600°C using significantly lower input power compared to fresh rocks. The findings also reveal that iron-based and other metal minerals in the sandstone rocks exhibit a noticeable natural catalytic effect in promoting CH4 conversion to H2, yielding over 70.0% H2 concentration as temperature approaches 650°C. In terms of oil conversion to hydrogen, a concentration of 60.7 mol.% H2 is achieved, accompanied by moderate percentages of CH4 and C2H4, along with a minor amount of CO. Additionally, water proves to enhance H2 generation via coke gasification within a temperature range of 330-580°C. Furthermore, throughout the experiments, negligible CO2 and minor CO emissions are observed, underscoring the potential for a carbon-zero H2 technology. The proposed technology holds promise in paving a new pathway for clean H2 production directly from oil and gas reservoirs.