Process simulation of CO2 absorption data fitted to performance efficiency at TCM Mongstad


  • Lars Erik Øi
  • Njål Sæter
  • Neda Razi
  • Sumudu Karunarathne



CO2, amine, absorption, simulation


This work's first aim is to fit the simulated results to pilot plant data from Test Centre Mongstad (TCM) for both high and low CO2 exhaust gas inlet concentrations. The next aim is to evaluate whether fitted parameters for one scenario (a set of experimental data under specified conditions) give reasonable predictions under other conditions. The scenarios at TCM have been simulated in both a rate-based model in Aspen Plus (RateSep) and an equilibrium-based model in Aspen HYSYS. The rate-based model’s performance data were fitted by only changing the liquid hold-up factor (multiplied with the hold-up estimated by the Bravo/Rocha/Fair correlations) to obtain the experimental CO2 removal efficiency. In the equilibrium-based model, a Murphree efficiency (EM) was specified for 24 or 18 stages (meter of packing) to fit the CO2 removal efficiency and the temperature profile from performance data. The specified EM profiles were then used to fit performance data for other scenarios by adjusting only an EM-factor, multiplying all the EM values in an EM profile. The performance (CO2 removal and temperature profile) was reasonably simulated for each given scenario for all the models. It is shown in this work that the use of the liquid hold-up factor (and not the interfacial area factor) is convenient to fit the rate-based model to the pilot plant data. Using fitted parameters at low CO2 inlet concentration to predict performance at high concentration needed an adjustment factor (liquid hold-up factor or EM-factor) to obtain correct CO2 removal predictions. A liquid hold-up factor of 0.72 and an EM-factor of 1.72 fitted to performance data for high CO2 concentration at TCM gave reasonable predictions compared to performance data for high CO2 concentration from the Esbjerg pilot plant.