Dynamic modeling and simulation of absorption of carbon dioxide into seawater

In order to elucidate the dynamic performance of the CO2 ocean disposal process, effects of operating parameters, such as gas flow rate, salinity and temperature, on the absorption of CO2 into seawater were examined. The rate-based model consisting of the rates of chemical reaction and gas-liquid mass transfer was developed for simulating dynamic process of CO2 ocean disposal. In modeling, non-ideal mixing characteristics in the gas and liquid phases are described using a tanks-in-series model with backflow. Experiments were performed to verify dynamic CO2 absorption prediction capability of the proposed model in a cylindrical bubble column. The operation was batch and continuous with respect to liquid phase and gas phase, respectively. Experimental results indicate that the CO2 gas injection rate increased the absorption rate but the increase in salinity concentration caused inhibition of the absorption Of CO2. The proposed model could describe the present experimental results for the dynamic changes and the steady-state values of dissolved CO2 Concentration and hydrogen ion concentration. The proposed model might effectively handle the prediction of the absorption of CO2 into seawater in the CO2 ocean disposal. (C) 2007 Elsevier Ltd. All rights reserved.