Degradation of amines is one of the most important issues to be addressed for absorption-desorption based post-combustion CO2 capture. Several laboratory studies have been performed to identify the degradation products and understand the mechanisms of degradation. However, there seems to be a gap in knowledge from translating the lab scale studies to observations from the pilot campaigns. Moreover, the observations from different pilot plant campaigns can be quite different. The objective of this study is to compare the solvent degradation behavior from different campaigns and highlight their causes in terms of solvent metal content and ammonia emissions. Results from the following different pilot plants are evaluated: (a) TNO's CO2 capture plant at Maasvlakte, the Netherlands, (b) EnBW's CO2 capture plant at Heilbronn, Germany and (c) ENEL's CO2 capture plant at Brindisi, Italy. The different rate of oxidative degradation are correlated to the different operating conditions and layout of the pilot plants. Along with these results, kinetic models based on laboratory studies are used to compare the pilot plant observations, highlighting the differences between lab-scale studies and pilot plant studies.@en

Oxidative degradation is a serious concern for upscaling of amine-based carbon capture technology. Different kinetic models have been proposed based on laboratory experiments, however the kinetic parameters included are limited to those relevant for a lab-scale system and not a capture plant. Besides, most of the models fail to recognize the catalytic effect of metals. The objective of this work is to develop a representative kinetic model based on an apparent auto-catalytic reaction mechanism between solvent degradation, corrosion and ammonia emissions. Measurements from four different pilot plants: (i) EnBW's plant at Heilbronn, Germany (ii) TNO's plant at Maasvlakte, The Netherlands; (iii) CSIRO's plants at Loy Yang and Tarong, Australia and (iv) DONG Energy's plant at Esbjerg, Denmark are utilized to propose a degradation kinetic model for 30 wt % ethanolamine (MEA) as the capture solvent. The kinetic parameters of the model were regressed based on the pilot plant campaign at EnBW. The kinetic model was validated by comparing it with the measurements at the remaining pilot campaigns. The model predicted the trends of ammonia emissions and metal concentration within the same order of magnitude. This study provides a methodology to establish a quantitative approach for predicting the onset of unacceptable degradation levels which can be further used to devise counter-measure strategies such as reclaiming and metal removal.@en

Various mechanisms have been proposed to explain the nonphotochemical laser-induced nucleation (NPLIN). Identifying the dominant mechanism requires addressing a large set of experimental parameters with a statistically significant number of samples, forced by the stochastic nature of nucleation. In this study, with aqueous KCl system, we focus on the nucleation probability as a function of laser wavelength, laser intensity, and sample supersaturation, whereas the influence of filtration and the laser-induced radiation pressure on NPLIN activity is also studied. To account for the nucleation stochasticity, we used 80-100 samples. The NPLIN probability showed an increase with increasing laser intensity. The results are different from the previous report, as a supersaturation independent intensity threshold is not observed. No dependence of the NPLIN probability on the laser wavelength (355, 532, and 1064 nm) was observed. Filtration of samples reduced the nucleation probability suggesting a pronounced role of impurities on NPLIN. The magnitude and the propagation velocity of the laser-induced radiation pressure were quantified using a pressure sensor under laser intensities ranging from 0.5 to 80 MW/cm2. No correlation was found between the radiation pressure and NPLIN at our unfocused laser beam intensities ruling out the radiation pressure as a possible cause for nucleation.@en