Exploring the Potential of Natural Gas Reservoirs for Underground Hydrogen Generation

Abstract

Abstract The major trends over a few last decades have been focused on the strategies to decrease global warming affection and to develop a new environmentally friendly and sustainable method to fulfill hydrogen demand as a highly promising energy carrier. Nowadays, hydrogen is produced through steam methane reforming (SMR), resulting in up to 10 kg of CO2 emissions per 1 kg of H2. One potential approach for producing low-carbon hydrogen directly in hydrocarbon-rich reservoirs, leaving all greenhouse gases stored in the reservoir, is a novel hybrid catalytic-thermal process. In the current study, we report results on the experimental study of in situ hydrogen generation conducted in an autoclave setup with samples of reservoir rock. A heated reactor containing the natural core model was continually loaded with methane and a water solution of nickel-based catalyst. The tests were carried out with varying steam-to-methane ratios, at pressure of 80 bar and at temperatures between 500 and 800°C. The results show that temperatures of no less than 600°C are necessary to convert a significant amount of methane to hydrogen-containing gas, likewise increased steam-to-methane ratio. Since the catalyst precursor forms nickel nanoparticles during the process, the study validates that a cheap, nickel-based catalyst precursor delivered in an inactive, water-soluble state can potentially be used to activate the primary hydrogen generation processes. So, in order to develop gas reservoirs, especially depleted ones, a novel proposed approach that converts methane into hydrogen can be used. A simple technique of introducing and applying hydrocarbon conversion catalyst confirmed its effectiveness despite the harmful influence of reservoir conditions. The proposed technology can make a significant contribution to global sustainability efforts via low carbon hydrogen production.