Effect Of Additives On Absorption/Desorption Performance Of MDEA-CO₂ System

The global warming caused by greenhouse gases has an increasingly significant impact on the survival and development of human beings.It is imperative that the reduction of greenhouse gas emissions such as CO2 and the prevention of global warming are urgent.Among the CO2 capture technology,the chemical absorption method is the most mature and widely used technology.As one of the most commonly used chemical absorbents,N-methyldiethanolamine(MDEA)has the problem of slow absorption rate.Researchers at home and abroad have studied the promotion effect of additives on CO2 absorption rate by adding organic solvent additives such as activator and methanol to MDEA.However,there is no systematic study on the comprehensive effects of additives,especially organic solvents,on the absorption and desorption properties of MDEA absorbents.In addition,there are few reports on the effect of compound additives of activator and organic solvent on the absorption rate of MDEA.In this paper,starting from the mechanism of different types of additives to increase the absorption rate of MDEA,by accelerating the reaction and enhancing the mass transfer,systematically studied and compared the effects of different types of additives on the absorption rate of MDEA,and investigated the different types of additives on CO2 loading and desorption The impact of performance such as rate.The research results show that although the activator that can accelerate the reaction has a significant effect on promoting the absorption rate of MDEA,there is a problem that the absorption rate decreases rapidly during the absorption process;and PZ can only be desorbed at a higher desorption temperature,and the energy consumption required Higher,not conducive to desorption.At 70? desorption temperature,the equilibrium desorption rate of MDEA is 62.4%,while the equilibrium desorption rate of MDEA/PZ can only reach 53.8%.At desorption temperature of 70?,the equilibrium desorption rate of MDEA/B is as high as 84.1%,while that of MDEA is only 62.4%.Organic solvents such as B,which can enhance mass transfer,have a significant effect on the absorption rate of MDEA,and are conducive to the desorption process.In addition,by compounding different types of additives,a compound additive has been developed that can be applied to an energy-efficient carbon capture process.MDEA/PZ/B absorption rate is 264.4%of MDEA absorption rate.At desorption temperature of 70?,the equilibrium desorption rate of MDEA/PZ/B absorbent is 75.5%,and the equilibrium desorption rate of MDEA/PZ absorbent is 53.8%.The addition of B can promote the desorption of MDEA/PZ absorbent.This shows that accelerating the reaction and enhancing mass transfer at the same time have a very good effect on the absorption rate and desorption process.