Extracting ethane from natural gas is a new trend in the development of natural gas condensate recovery technology. The study on the 1.5 million m3/d natural gas ethane recovery process was carried out in order to achieve the goals of reducing energy consumption and improving ethane recovery rate. The study results show that all three processes can meet the ethane recovery rate of more than 90%. The Recycle Split-Vapor Process can further increase the ethane recovery rate at the expense of increasing the energy consumption per unit product, and the Gas Subcooled Process has the lowest energy consumption. Study on the main parameters of the Gas Subcooled Process shows that the ethane recovery rate gradually increases as the feed gas temperature goes lower and as the proportion of sub-cooled gas ratio increases. The energy consumption per unit product decreases first and then increases. When the operating pressure of the demethanizer is increased, the energy consumption per unit product does not change significantly, but the ethane recovery rate gradually decreases. When the feed gas is pre-cooled to -65 ℃, with the demethanizer operating pressure at 2 100 kPa and the sub-cooled gas ratio is 25%, the crude ethane gas product is 151 kmol/h, giving an ethane recovery rate of 95.25%, and the energy consumption per unit product is 173 MJ/kmol. This research result can provide a reference for similar engineering design and optimization.