Simulation and optimization of hydrogen separation from hydrogenation tail gas by hydrate-membrane coupled method

Abstract

A pressure swing hydrate-membrane coupled separation (PSHMS) process was designed, and process simulation was conducted using a combination of Aspen Plus and Excel. PSHMS achieves continuous, highly efficient, and stable production of qualified gaseous products without thermodynamic promoters of hydrate or circulating working fluids. In hydrogen separation from diesel hydrogenation tail gas, PSHMS exhibits lower energy consumption and higher efficiency compared to hydrate-based separation technologies. Sensitivity analyses of various design parameters within PSHMS were performed through simulation, the results indicate that low temperature, high initial pressure, and high water content are all advantageous for improving separation efficiency. The selection of feed rates needs to be determined comprehensively based on the design parameters. The optimized unit energy consumption of PSHMS is merely 46.41 kJ/mol, significantly lower than the 117.94 kJ/mol of hydrate-based separation technology.