Fluctuating energy sources require enhanced energy storage demand, in order to ensure safe energy supply. Power to gas offers a promising pathway for energy storage in existing natural gas infrastructure, if valid regulations are met. To improve interaction between energy supply and storage, a flexible power to gas process is necessary. An innovative multibed methanation concept, based on ceramic honeycomb catalysts combined with polyimide membrane gas upgrading, is presented in this study. Cordierite monoliths are coated with $\gamma$-Al₂O₃ and catalytically active nickel, and used in a two-stage methanation process at different operation conditions (p = 6–14 bar, GHSV = 3000–6000 h⁻¹). To fulfill the requirements of the Austrian natural gas network, the product gas must achieve a CH₄ content of ≥96 vol %. Hence, CH₄ rich gas from methanation is fed to the subsequent gas upgrading unit, to separate remaining H₂ and CO₂. In the present study, two different membrane modules were investigated. The results of methanation and gas separation clearly indicate the high potential of the presented process. At preferred operation conditions, target concentration of 96 vol % CH₄ can be achieved.

Click on the article title to read more.