Modelling Vapour − Liquid Equilibrium of CO2 in Aqueous N-Methyldiethanolamine through the Simulated Annealing Algorithm

The modified Clegg-Pitzer equation is used to correlate and predict the vapor-liquid equilibrium of the CO2-MDEA-H2O system. Simulated annealing (SA), a computational stochastic technique for finding near global minimum solutions to optimization problems, has been used for parameter estimation in the model to predict VLE of CO2 in aqueous MDEA solution. The solubility of CO2 in aqueous solutions of 23.8 wt % and 30.0 wt % of N-methyldiethanolamine (MDEA) has been measured over the temperature range of 303-323 K and CO2 partial pressure range of 1 to 100 kPa. The model predicted equilibria have been found to be in good agreement with the experimental results of VLE measurement of this work as well as those in the open literature. In this work, the SA technique has been used as an alternative to the traditional Levenberg-Marquardt (LM) technique, to predict the VLE data accurately.