Simulation of carbon dioxide - monoethanolamine - water system using equilibrium approach

Abstract

Carbon Dioxide is a greenhouse gas and has been identified as the prime source of global warming and climate changes. So the major challenge ahead of us is the capture and removal of CO2. Though there are different methods and technologies available, the most efficient method is the use of an absorption/stripping process with a chemical solvent for absorption. Various solvent have been tried, but aqueous monoethanolamine remains the most common and popular solvent. This thesis focuses on the development of a comprehensive flowsheet based on the thermodynamic model which assumes the overall process to be at equilibrium. The ASPEN PLUS software was used for developing and simulating the problem. The Electrolyte–NRTL model was chosen as the base method with ensured the use of predefined physical properties, thermodynamics and kinetics for the simulation of the process. Once the simulation is over and it properly converges giving an acceptable capture percentage , sensitivity analysis were carried out to study and get an rough idea about the nature and extent of the effect of different parameters on the reboiler duty or energy requirement and other properties like amine flow rate . The simulation based on thermodynamic model is the stepping stone for the more complex and tedious rate based studies as its gives us an estimate of different properties and constraints.