The screen blade impeller was compared with the flat blade impeller in a four stage counter current column extractor, where nicotine in water （drop phase） was extracted by kerosene (continuous phase).
The extraction efficiency was measured as a function of the impeller rotation, the flow rate, and the screen opening. The drop size and the drop hold-up were also measured and the results were correlated with the impeller rotation.
Through this investigation, it could be concluded that, when the same power consumed, the screen blade is more effective than the flat blade in the extractor. The above conclusion was well interpreted with the experimental results for the drop size and the hold-up.