Experimental study of adsorption CO₂ storage device for compressed CO₂ energy storage system

Compressed CO₂ energy storage is a reliable physical energy storage solution. The main challenge of compressed CO₂ energy storage system is how to solve the high-density storage of low-pressure CO₂. In this study, we proposed a new type of adsorption transcritical compressed CO₂ energy storage system. We used adsorbents to adsorb CO₂ for achieving low-pressure, high-density storage of low-pressure CO₂. We investigated the gas storage capacity of the adsorption storage system and the heat and mass transfer process. Results demonstrate that the storage density (57.6 °C–25 °C) of adsorption gas storage is 43.46 kg/m³, which is 24.8 times of the CO₂ density (1.75 kg/m³, 30 °C, 1 bar). If the adsorbents are heated above 160 °C, then the storage density will increase 3–4 times. The whole process is controlled by heat exchange efficiency. The heat exchange efficiency greatly affects the response time of the system during the application.