In order to separating the impurities in plant seeds a tribo-airo-electrostatic system designed and constructed and evaluated based on maximum separation of pure Descurainia seed. The separating process takes place by considering physical relations. There are two important forces that in acts on the falling object in electric field; the electric force acts in the horizontal direction, gravitational force acts in the vertical direction. The raw materials received the ststic charge in the tribo-charge unit and the charged materials conducted to the separator unit. In the separator unit seeds and impure particles were affected by gravitational and electrostatic force with higher DC voltage (40kV). Laser diffraction method used for determination the size of separated particles and for this purpose FRITSCH Laser Particle Size Analyser -ANALYSETTE 22 NanoTec system was used. The results showed that in box no.1 the value of the particle in the range of 210-680 is the least while in the range of 680-980 it is the highest range. The purity of Descurainia seed in section no.1 was about 99.5%. According to the results it can be stated that this system can be used for separation and purification of small grains such as alfalfa and clover.
