Overall mass transfer coefficient and time averaged mass transfer coefficient of adsorption of SO_2 on activated industrial semi-cokes

The experimental study on activated semi-cokes absorbing SO2 was done.The breakthrough curves were drew from the experimental data.Overall mass transfer coefficients were calculated.Time averaged mass transfer coefficient was proposed,calculated and correlated with experimental conditions.The calculation result of overall mass transfer coefficients shows that the process of activated semi-cokes absorbing SO2 is controlled by inner diffusion or external diffusion separately at different stages,and belongs to multi-step combined control process.When the temperature of the process increases,the overall mass transfer coefficients enlarge and the stage controlled by external diffusion is extended.The calculation result of time averaged mass transfer coefficients indicts that a time averaged mass transfer coefficient can represent the intensity of a adsorption mass transfer process quantitatively,and can correlated with experimental conditions.The regression expression shows that to increase the temperature of the adsorption bed or the flow rate of gas can all enlarge the time averaged mass transfer coefficient,and can reinforce the adsorption mass transfer process consequently.