Inline Monitoring of CO2 Absorption Processes Using Simple Analytical Techniques and Multivariate Modeling

The solvent and the dissolved CO2 concentrations are two essential properties of CO2 absorption processes. Currently, they are typically monitored using time-consuming offline analytical techniques. Initial development efforts aiming at a cost-effective and reliable inline monitoring system are described. Using a fractional factorial experimental design covering six solvent properties and five analytical techniques, it is demonstrated that the CO2 and solvent concentrations correlate well with the density and refractive index. Applying a simplistic multivariate model to solvent samples from an industrial pilot plant indicated good potential for predictive use. Future work should focus on the development of a more accurate multivariate model, on the modeling of more solvents, and on combining the results with available process data. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.