Abstract: According to structure and fluid flow characteristics, the mixing mechanism of a gas stream in the corrugated plate packing was analyzed. Three types of mixing were identified: 1. Mixing at the channel intersections between adjacent plates, 2. Mixing near the wall region, 3. Mixing at the interface between adjacent elements. A mathematical model with three parameters has been proposed for predicting the radial concentration profile at a given height. The results showed that the predicted values fit the experimental data satisfactorily.