Solvent managementis one of the important current challenges inpost combustion carbon capture (PCC) technology development. Usinglarge-scale 1960 h test campaign data (Technology Centre Mongstad,Norway, 2015 MEA Test), we demonstrate a combination of multivariatemethods (PLS-R, MSPC) and process analytical spectroscopy (FT-IR)as a tool to monitor and control PCC process performance. Two MEAsolvent monitoring models, total inorganic carbon (TIC) content andtotal alkalinity (TA), were prepared. In long-term solvent monitoring,PLS-R model prediction uncertainty increased due to gradual solventchanges, e.g., solvent degradation and impurity accumulation. Hence,we show a specific model update methodology to keep the models updated,leading to good long-term monitoring ability of the TIC and TA models.In addition to reliable long-term solvent monitoring ability, a newprinciple for follow-up of thermal solvent reclaiming was demonstrated.This shows that the need for solvent reclaiming can be quantified.Furthermore, this methodology is an indicator to see the actual solventdeviation from the fresh solvent. This quantification may providean input for "start" and "end of reclaiming operation"identification. Hence, we demonstrate that it is possible to extractinformation for process performance follow-up, solvent monitoring,and solvent reclaiming from a single spectroscopic instrument.