The removal of carbon dioxide with activated solutions of methyl-diethanol-amine

In this paper mixtures of MDEA with several activators, being primary and secondary amines, are studied with respect to the performance of CO2 removal from natural gas. The absorption process in a tray column has been simulated. For a number of default cases the impact of the activator on the total number of trays has been calculated. From these simulations the optimal number of trays in combination with the amount of activator-addition can be established. Furthermore, insight is obtained on the mechanism of the absorption steps in mixed amine solutions. It is demonstrated that the working action of the accelerator, the fast reacting amine, is substantially influenced by the partial pressures of carbon dioxide in the gas mixture. Moreover, this effect is strongly depending on the molar fraction of the accelerator.