Numerical Investigation of Heat Transfer Characteristics Between Thermochemical Heat Storage Materials and Compressed Natural Gas in a Moving Bed

To promote energy conservation and a low-carbon approach in natural gas storage, efficient methods for utilizing waste heat during gas injection and maintaining adequate cooling rates are crucial. This study developed a three-dimensional model integrating the desorption process of hydrated salts to analyze temperature and flow fields within a moving bed during heat exchange. This study systematically evaluated the effects of operating parameters on key outcomes, including the outlet temperatures of hydrated salts and natural gas, as well as the waste heat recovery ratio. Results indicated that the outlet temperatures of natural gas and particles varied synchronously, while the waste heat recovery ratio exhibited an inverse relationship with the natural gas outlet temperature. Remarkably, incorporating a composite material comprising hydrated calcium chloride and hydrated magnesium sulfate into the moving bed reduced the natural gas outlet temperature from 60 °C to 47.5 °C. Concurrently, the waste heat recovery ratio improved substantially, rising from 66% to 90%. Furthermore, the proposed moving bed heat exchange system requires less than one-third of the volume of conventional natural gas air-cooled heat exchangers. These findings provide theoretical insights and robust data support for enhancing cross-seasonal waste heat utilization in natural gas storage facilities.