Heat transfer enhancement-driven synergistic kinetic promotion of methane hydrate formation-dissociation cycles for advanced solidified natural gas technology

The rising demand for natural gas, driven by its lower carbon footprint and abundant reserves, has intensified the focus on developing efficient, safe, and sustainable gas storage solutions. Hydrate-based solidified natural gas (SNG) technology stands out as a promising environmentally friendly option, offering advantages such as low energy consumption and reduced carbon emissions. However, its commercial deployment remains limited by the inherently slow kinetics of hydrate formation and the inefficient release of gas during dissociation. To address these dual challenges, this study investigated the pivotal role of heat transfer in enhancing the kinetics of both methane hydrate formation and dissociation. Porous sediments with varying thermal conductivities were prepared by adjusting the volume ratios of silica and alumina particles, thereby systematically modifying their heat transfer properties. Experimental results demonstrate that improved heat transfer effectively accelerated both hydrate formation and dissociation process, enabling more efficient gas storage and release. Specifically, the average hydrate formation rates at t50 and t90 in the high-thermal-conductivity alumina sediment were 5.08 and 6.27 times higher, respectively, than those in the low-thermal-conductivity silica sediment. During dissociation, the time interval between t50 and t90 was reduced by 59.10 % in the alumina sediment. These findings provide mechanistic insights into the critical role of thermal management in promoting hydrate formation and dissociation and overcoming kinetic limitations. The results offer practical guidance for designing thermally efficient hydrate-based SNG systems and contribute to the advancement of scalable, industrial-ready technologies for low-carbon energy storage and transportation.