Experimental Studies Of Hydrodynamic Performance Of DX Structured Packing And Mass Transfer Performance Of CO₂ Absorption Into DEEA Solution

The large amount of carbon dioxide derived from human activities has been blamed for the increasing serious and complex environmental problems such as smog,wealth events and global warming.Post-combustion CO2 capture based on amine chemical absorption is considered to be the most promising methodology for application in CO2 capture and storage(CCS).A packed column,widely used in CO2 mass and heat transfer reactor,has greatly determined the costs of amine-based CO2 capture.Thus,improving the mass and heat transfer in packed column is turns to be the focus of amine-based CO2 capture.Nowadays,development of efficient absorbents and improvement of packing performance are effect ways to improve the mass and heat transfer in packed column.In this work,a new structured packing(Sulzer DX packing)and a promising blend amine solvent(N,N-Diethylethanolamine(DEEA))were investigated to improve CO2 mass transfer performance in packed column.The effective interfacial area(av),hydrodynamic performance of DX structured packing and mass transfer performance of DEEA solution were comprehensive investigated in DX structured packing column.The experimental results obtained from this work are as follows:(1)The effective interfacial area(av)of DX structured packing was measured based on chemical reaction between CO2 and NaOH solution to explore the gas and liquid flow rate on av.The experimental results obtained from this work showed that the values of av increase with the increasing of gas and liquid flow rate.(2)The hydrodynamic performance of DX structured packing was evaluated in water-air system.The Bain-Haugen flooding velocity correlation models were developed based on the pressure drop and liquid hold up correlation graph.The experimental result show that the pressure drop profiles in air-water systems is liner a low liquid flow rate,however,the different trend was obtained in high liquid flow rate.Besides,the flooding velocities in MEA-CO2-H2O systems increase with increasing CO2 partial pressure and the pressure drop is higher than that in water-air system.From bottom to the top of the absorber,the pressure drop increases slowly then increases rapidly.At last,the effective volume of dead space per volume of packed bed(kL)was derived from Billet pressure drop model.The results showed that kL was affected by operational parameters such as liquid and gas flow rates.The KL values decrease with a reduction of the liquid flow rate,however,The KL values remains approximately constant at the low gas flow rate,then increases rapidly the gas flow rate increases beyond the flooding point,based on this trend,the KL was found to be liner function of liquid hold up.(3)The mass transfer performance of DEEA solution was investigated in DX structured packing column.The results showed that the volumetric overall mass transfer coefficient(KGav)and unit volume absorption rate(?)increases liquid feed temperature and liquid flow rate increase,and decreases with increasing CO2 loading,while increasing inert gas flow rate have little effect on KGav,but increases ?.Besides,KGav decreases while ? increases with increasing CO2 partial pressure.At last,correlations for KGav and yoit proposed for CO2 absorption into DEEA in DX structured packing column were found to give a satisfactory fit to the experimental results with an AAD of 7.9%and 10.0%...