The most widely used impeller types in agitators are paddle impeller, propeller, turbine impeller and anchor impeller, accounting about 75-80% of the total. Here describes the applicable conditions of the above four kind of impellers: 1.  Paddle impeller are used in liquid-liquid system mixing to prevent separation and make the temperature uniform in the tank;  and in solid-liquid system mixing, paddle impeller are mostly used to prevent solid settlement. 2. The propeller is mainly used in the m