Carbon dioxide recovery from urea manufacturing plant

Carbon dioxide is one of the most important greenhouse gas that is threatening the present day human life as well as the quality of the environment, resulting in large scale effects (disasters) on the living organisms. The present work aims to employ process simulation software (Aspen Plus software) for the recovery of carbon dioxide evolved from the urea manufacturing plant. Though, commonly used solvent for the removal of carbon dioxide is Monoethanolamine, in this work CO2 extraction was by studied by employing three more solvents i.e., Diethanolamine, Methyl diethanolamine and Diglycolamine. An effective UNIFAC method is used to estimate the CO2 recovery (from carbon dioxide recovery plant). The recovery of CO2 is estimated at different absorber & stripper temperature conditions and concentrations of the solvent(s). The results of the solvents are compared to identify best operating parameters (solvent temperature and concentration). In absorber the overall percentage of CO2 removal from the flue gas for all the solvents was found to be; 99.983% with Diglycololamine solvent (at 0.55 concentration (mole%) and 10°C temperature), 99.981% with Methyldiethanolamine solvent (at 0.55 (mole%) concentration and 5°C temperature), 99.74% with Diethanolamine solvent (at 0.5 (mole%) concentration and 8°C temperature) and 98.07% with Monoethanolamine solvent (at 0.2 mole% concentration and 8°C temperature). From the results of this study, Diglycolamine is the best solvent to remove carbon dioxide from flue gas.