Access to new types of energy resources for developing countries is essential for their economic development. New researches have shown that there is a direct relationship between a country's level of development and its energy consumption. Due to limited fossil energy resources and increasing energy consumption in today's world, it is no longer possible to rely on these resources. A significant portion of this energy is used for gas separation processes in various industries. Therefore, developing the gas separation processes with reduced energy consumption is of great importance. In this case, cryogenic-membrane gas separation hybrid processes have been very effective in air separation, synthesis gas production, propane recovery, biogas upgrading, CO2 capture, and hydrogen and helium recovery from natural gas due to their cost-effectiveness and energy efficiency. This chapter discusses the merits and demerits of membrane and cryogenic processes separately, examines cryogenic-membrane gas separation hybrid processes, and then explores their application in industrial gas separations.
