Dynamic modeling and simulation of absorption of carbon dioxide into seawater

Abstract

In order to elucidate the dynamic performance of the CO 2 ocean disposal process, effects of operating parameters, such as gas flow rate, salinity and temperature, on the absorption of CO 2 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 CO 2 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 CO 2 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 CO 2 gas injection rate increased the absorption rate but the increase in salinity concentration caused inhibition of the absorption of CO 2 . The proposed model could describe the present experimental results for the dynamic changes and the steady-state values of dissolved CO 2 concentration and hydrogen ion concentration. The proposed model might effectively handle the prediction of the absorption of CO 2 into seawater in the CO 2 ocean disposal.