In this paper, the flow patterns of the dispersed air bubbles in the small flotation cells of the batch and free-flow types with a constant rotating speed of the impeller and with constant self-air-induction are discussed by the aid of a photographic technique.
Besides, under these conditions, the distribution of the air bubbles rising toward the pulp surfaces are discussed.
The main experimental results are summarized as follows ;
1) The flow pattern of the air bubbles in the conventional batch type cell is different from that in the conventional free-flow type cell.
The both patterns, however, are considerably similar to each other in case that the pulpe circulation holes are made on the hood plate of the cell. Furthermore, in the latter case air bubbles are more uniformly distributed in the cell than in the former cases.
2) In the free-flow type cell, as the quantity of flow is increased, the flow pattern of the air bubbles near the charge side becomes much different from that near the discharge side, but this difference between the flow-patterns of the both side is considerably diminished by making the circulation holes on the hood plate of the cell.
3) The buffle plates equipped in the cell reduce the horizontal component of the rotational velocity of pulpe and produce impulsive streams diverging into the upper and down streams in the cell. Thus, the flow pattern of air bubbles is greately influenced by these phenomena.
As a matter of couse, the effect of the buffle plates on the distribution of rising bubbles is greatest in the vicinities of the buffle plates.

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