Experimental and numerical study on CO₂ absorption mass transfer enhancement for a diameter-varying spray tower

In this research article, orthogonal experiments were performed in a proposed diameter-varying spray tower system to evaluate the importance of operating parameters and analyse the relationship between factors and the mass transfer evaluation indices (the CO₂ removal rate and overall absorption rate). Two different spray methods such as dual-nozzle opposed impinging and spray in the middle method were discussed for performance comparison. Optimal operating conditions for different evaluation indices were obtained by using range analysis. After analysis it was found that the absorption performance was mainly affected by two parameters, monoethanolamine concentration and CO₂ concentration. The effects of different operating parameters on the CO₂ removal rate and overall absorption rate were also discussed by using trend analysis. Furthermore, gas phase mass transfer coefficient and effective contacting area were determined by experimental data. A comparison with reported conventional reactor systems demonstrated a great application potential for proposed spray tower in CO₂ capture. Finally, simulation results were illustrated which shows that the gas phase and liquid phase distributions for the dual-nozzle opposed impinging spray method enhance CO₂ absorption performance.