Frank Seibert

Dynamic Validation of Model for Post-Combustion Chemical Absorption CO2 Capture Plant

Abstract Dynamic modelling for post-combustion CO 2 capture using monoethanolamine (MEA) solvent has been validated at steady state in the past. This paper presents a dynamic validation. The absorber and regenerator were modelled using the two-film theory in gPROMS®. Electrolyte NRTL model in Aspen Properties® is used to describe the chemical equilibrium and vapour-liquid equilibrium. The CO 2 capture process was simulated. The temperature profile of the absorber, the capture level and the regenerator duty were compared with pilot plant data logs. It is observed that the model satisfactorily predicts the behaviour of the pilot plant due to a number of process inputs and disturbances, producing trends in close agreement with the data logs.

- Effective Gas/Liquid Contact Area of Packing for CO 2 absoprtion/stripping

Publisher Summary A typical application of low-pressure absorption using packing columns is carbon dioxide (CO2) capture. CO2 absorption by aqueous solutions occurs by mass transfer with chemical reaction in the liquid boundary layer. In carbon dioxide absorption, the rate of mass transfer primarily depends on the gas/liquid contact area, not on mass transfer rates within the phases. This chapter presents a study that aims to describe a method for measuring directly the interfacial area using a well-known chemical absorption system, air/ CO2/caustic. In this study, an experimental technique has been developed that allows direct measurement of the contact area for gas/liquid contacting. To minimize the effect of gas phase mass transfer resistance and associated errors in the measured contact areas, a dilute caustic (0.1 N NaOH) solution is utilized. Effective gas/liquid contact areas for a variety of commercially significant random and structured packings, obtained from a 42-cm diameter scrubber, have been provided. The effects of liquid and gas rates and their influence on liquid spreading and rivulet formation have also been discussed.