Objectives The aim is to solve the problems of large ethane loss and high energy consumption of the unit caused by the alcohol amine method ethane decarburization process.

Methods Aspen HYSYS software was used to simulate the amine method decarbonization of crude ethane products in an ethane recovery process, and the mass fraction of PZ and MDEA in the amine solution were optimized under the condition that the ethane loss ratio(calculated by molar flow) was controlled to be less than 0.3%. At the same time, the energy consumption of the ethane decarbonization process was optimized.

Results Different from the natural gas decarburization process, if the MDEA mass fraction of the ethane decarburization process is too high, a large amount of ethane will be lost. On the premise of achieving decarbonization effect, the lower MDEA mass fraction could avoid the loss of a large amount of ethane.The best MDEA mass fraction was 20%-28%. Under this MDEA mass fraction, low concentration amine liquid could ensure that the ethane loss ratio was only 0.3%. Adding a small amount of piperazine(PZ) to the amine liquid could significantly improve the absorption effect of amine liquid on CO₂. The best PZ mass fraction was 2.5%-5.5%. The main energy consumption of ethane decarbonization unit was amine regeneration energy consumption. After optimizing, the total energy consumption of the unit was significantly reduced.

Conclusions Under industrial conditions, the application of amine solution with lower mass fraction can significantly reduce the loss of ethane, and the energy consumption of the unit can be reduced by reasonably increasing the temperature of rich amine solution entering the regeneration tower or by appropriately reducing the circulating volume flow of decarbonization solution.