N-Methyldiethanolamine (MDEA) is commonly used to solve the acid gas containing hydrogen sulfide and CO2 in industrial production. It can absorb hydrogen sulfide and part of CO2. Many countries have done many experiments on the adsorption of acid gas by methyldiethanolamine, and it has been industrialized, and excellent results have been obtained. Because of the continuous development of this process, it is urgently needed for MDEA to make accurate prediction and analysis on the adsorption effect of hydrogen sulfide and CO2. However, the complexity of the absorption process includes not only the balance of chemical reactions, but also physical adsorption, as well as kinetic factors, which makes it difficult to accurately predict and analyze the adsorption status of hydrogen sulfide and CO2.

For the desulfurization and decarbonization operation process in the natural gas purification plant, the concept of equilibrium solubility and material balance were selected to create a mathematical analysis model for the selective adsorption of H2S and CO2 in N-Methyldiethanolamine aqueous solution, and numerical values were made for specific industrial production operations. simulation. Each investigated factors such as the use pressure and amine circulation volume to study the absorption of acid gas in the absorption tower, and calculated that it is difficult to increase the use pressure and the flow rate of the adsorption liquid to increase the amount of CO2 absorption, and the predicted value of the model was compared with the specific The comparison was made under the circumstances. The data simulation conclusion points out the improvement measures and methods under this specific condition, that is, the method of removing CO2 in the middle stage, the volume fraction of CO2 in the gas can be reduced from 4.7% to 3%, which meets the production standard. These conclusions provide a theoretical basis for the practical operation and renovation of the absorption tower.