Study on deep decarbonization and split desorption process of natural gas

At present, the energy consumption of conventional natural gas deep decarbonization process is high, which are shown as follows: high temperature of the regenerator, large heat load of reboiler, simple heat exchange flow, small heat exchange network integration, and the high heat loss. A split desorption process was studied. In this process, two materials entered the regenerator to recover the heat of the top gas in the regenerator, and reduce the cooling water flow of overhead cooler, thereby reducing the heat load of reboiler and achieving a certain energy saving effect. The results showed that the split desorption process could save more energy than the conventional process. When the CO₂ molar fraction in the feed gas was 3.63%, the optimum split ratio was 0.3, and then the purification effect was best. When the CO₂ molar fraction in the feed gas was 20%, the optimum split ratio was 0.4, and then the purification effect was best. When the second stock was selected for the feed position, it was recommended that the eighth plate should be selected as the optimum feed position.