Method and apparatus for separating crops and impurities

摘要

A method and an apparatus for separating crops and impurities are described, which exploit the different specific gravities of the materials to be separated. The separation is performed with the help of a liquid exploiting the different lifting forces, since the materials to be separated differ clearly in specific gravity. If the specific gravity of the separating liquid does not suffice to effect the necessary lift for the crop, one produces a flow acting against the sinking direction of the impurities to increase the lifting force for the crop and cause it to collect by floating on the surface of the separating liquid. Water is preferably utilized as a separating liquid, and the flow is produced with the help of a pump wheel or bucket wheel. The method has proven especially useful for separating potatoes and stones.