Comparison of ammonia and monoethanolamine solvents to reduce CO₂ greenhouse gas emissions

This paper presents experimental results on the evaluation of two reagents, ammonia (NH₃) and monoethanolamine (MEA) solvents, for scrubbing carbon dioxide (CO₂) greenhouse gas emissions. The scrubbing of CO₂ by NH₃ solvent is a novel study developed by the authors, and the MEA process is a traditional process for gas purification of removing CO₂. The performance of these two solvents are compared in terms of CO₂ removal efficiency and absorption capacity. Test results show that both the CO₂ removal efficiency and absorption capacity of NH₃ solvent are better than those of MEA solvent under the operating conditions conducted in this study. The maximum CO₂ removal efficiency by NH₃ solvent can achieve 99% and the CO₂ absorption capacity can approach 1.20 kg CO₂/kg NH₃. On the other hand, the maximum CO₂ removal efficiency and absorption capacity by MEA solvent are 94% and 0.40 kg CO₂/kg MEA, respectively, under the same operating conditions tested by NH₃ solvent. Besides, the temperature increases due to exothermal reactions in the NH₃ scrubbing process are lower than those in the MEA scrubbing process. This indicates that the energy requirement for the regeneration of NH₃ reagent should be less than that for the regeneration of MEA reagent. Copyright (C) 1999 Elsevier Science B.V. All rights reserved.