Investigation of overall mass transfer coefficient of CO2 absorption in to aqueous blended Monoethanolamine (MEA), Diethanolamine (DEA) and Triethanolamine (TEA) measured in Bubble column Reactor solution

Abstract

Mixtures of different types of amine solution (primary Monoethanolamine (MEA), secondary : diethanolamine (DEA) and tertiary: triethanolamine (TEA) were experimentally used to investigation the overall mass transfer coefficient (KGa ) at different operating parameters. The experiments were made in a bubble column reactor (BCR) with 1.5 m in high and 0.1 m inside diameter as a gas-liquid contactor at 25°C and atmospheric pressure, using a simulation gaseous mixture (air, carbon dioxide) with recycle stream (circulation process). For efficient experimentation, the Taguchi method was applied for experimental design. A four factor and three levels was chosen for this study and it was exploded using L9 (34) orthogonal array design. These parameters for circulation process were namely: gas flow rate 10,15, and 20L/min, air flow rate100,150, and 200 L/h, liquid flow rate 5,10, and 15 L/min and time absorption time 30,60, and 90min. To understand the effectiveness order of different operating parameters, two factors namely, overall mass transfer coefficient (KGa ), and CO 2 loading (α) are to be exploded. A Shimadzu GC-8A Gas Chromatograph with thermal conductivity detector was used to measure the CO 2 concentration absorbed in aqueous blended solution. As per Taguchi analysis the significance sequence influencing the parameter and optimum condition can be determined. The maximum value for CO 2 loading was 3.439 (mol CO2/mol amine) at 20 L/min gas flow and 15 L/min liquid flow, and 200 L/h air flow for 60 min from absorption time. The performance was evaluated in terms of the overall mass transfer coefficient, KGav , the results show that max value of KGa was 0.08 S −1