Amine post-combustion carbon capture technology is based on washing the flue gas with a solvent that captures CO₂. Thus, a small fraction of this solvent can be released together with the cleaned flue gas. This release may cause environmental concerns, both directly and indirectly through subsequent solvent degradation into other substances in the atmosphere. The paper presents the ammonia emission from CO₂ capture pilot plant (1 tonne CO₂ per day) using 40 wt% aminoethylethanolamine solvent, along with the efficiency of the water wash unit. In addition, the temperature effect of lean amine entering the absorber on ammonia emission was studied. Furthermore, the concentrations of other compounds such as SO₂, SO₃, NO₂, CS₂ and formaldehyde were monitored. The literature review on the NH₃ emission from a pilot plant using aminoethylethanolamine solvent has not been published. The results show that the main source of ammonia emission is the absorber and that emission (in the range 27–50 ppm) corresponds to typical NH₃ release from CO₂ capture pilot plant using an amine solvent. The emission of amines and amine degradation products is a complex phenomenon which is difficult to predict in novel solvents, and for this reason the significance of new solvents testing in a pilot scale has been highlighted.

The aqueous solutions of various amines are used as chemical absorbents in gas treating processes. It is considered that aqueous ammonia can be used as a promising solvent for CO2 capture. Apart from the many advantages of ammonia as a CO2 capture solvent, its major drawback is high volatility. As a consequence, a large amount of ammonia can be released into the atmosphere. In this paper we investigated the effects of process parameters on ammonia emissions from the absorber used for CO2 capture. Ammonia solution withdrawn from the ammonia recovery tower of the Solvay Process was used as solvent. During the research, the absorber pressure, liquid to gas flow ratio (L/G) and concentration of ammonia have been varied. In addition, a novel simple method for quantitative analysis of absorbed CO2 in the ammonia solvent was described. We found that increasing the L/G ratio and ammonia concentration in the solvent resulted in a growth of ammonia emissions. The amount of released ammonia from the absorber was in the range 14-46 mg/dm3. However, it is important to note that no emission reduction devices were applied. The test of CO2 capture using aqueous ammonia was satisfactory, with more than 90% of the inlet CO2 stream being removed. Instytut Chemicznej Przeróbki Węgla, Zamkowa 1, 41-803 Zabrze, Poland

Since fossil fuels still dominate industry and electricity production, post-combustion carbon capture remains essential for decarbonizing these sectors. The most advanced technique for widespread application, particularly in hard-to-abate industries, is amine-based absorption. However, increasing energy efficiency is crucial for broader implementation. This study presents pilot-scale results from the Tauron Power Plant in Poland using a mobile CO₂ capture unit (1 TPD). Two innovative process modifications—Split Flow (SF) and Heat Integrated Stripper (HIS)—were experimentally investigated; they achieved a 10% reduction in reboiler heat duty, reaching 2.82 MJ/kg_CO2, along with a 36% decrease in overall heat losses and up to a 28% reduction in cross-flow heat exchanger duty. The analysis highlights both the advantages and challenges of these modifications. SF is easier to retrofit into existing plants, whereas the HIS requires more extensive modifications in the stripper section, thus making HIS more cost-effective for new installations. Moreover, as heat consumption constitutes the primary operational cost, even a moderate reduction in heat duty can lead to significant economic benefits. The HIS also offers substantial potential for thermal integration in industries with available waste heat streams. The pilot data underwent validation procedures to ensure reliability, which provides a robust foundation for process modeling, optimization, and scaling for industrial applications.