An Investigation on Pumping Effect in Pump-mix Type Mixer-settler Extractor.

The suction and extrusion pressures were measured by using a vaned disk and a plate turbine as an impeller of mixer-settler extractor. The suction effect by a vaned disk and extrusion effect by a plate turbine are strongly dependent on the rotation speed, and they slightly decrease with an increase in the flow rate due to the pressure drop. When the flow rate is zero, the maximum suction and extrusion pressures are obtained. The both pressures at a certain flow rate are in good agreement with the difference between the maximum pressure and the total pressure drop. The maximum suction and extrusion pressures are nearly proportional to the third power of rotation speed. The suction pressure is also dependent upon the distance from the vaned disk to the bottom of the mixing space, and in the same manner the extrusion pressure depends on the distance from the plate turbine to the extrusion pipe of the mixing space. When the distance is shorter, the effect becomes higher. If the rotation speed is fixed, the desired suction and extrusion pressures are obtained by adjusting the distance.