Development of a vibrationless sorting system

Abstract

Aim of study: Size classification is essential in many industrial processes. Most classical sorting systems use vibrations as a means of classification function. In this study, a vibration-free sorting system called helical cylindrical screen has been developed against the disadvantages of vibrating systems and proposed to be used in the sorting of crop seeds.Area of study: Adana City, Turkey.Material and methods: The movement of the seed mass on the screen surface was formulated and the mass movement along the circular-helical paths was analytically expressed, leading to some operational parameters for evaluation in the screen design. By combining the mass movement parameters with effective separation conditions, an algorithm was obtained against the desired mass flow rate to determine the appropriate values of the design parameters. Experiments were performed on the machine, which was manufactured to sort peanut seeds into two different sizes, small and large.Main results: The results obtained in the experiments (separation efficiency, mass flow rate, effect of grain size on separation efficiency and equilibrium angle) were compared with the theoretical ones. The separation efficiency of the machine (99% and above) was quite good and is not affected at all by the small size ratio contained in the mixtures. The limitations of the theoretical velocities (axis and tangent) of a seed moving on the cylindrical sieve were found to be consistent with those obtained experimentally.Research highlights: The helical cylindrical sieve can be used for other particulate agricultural products with smooth surfaces such as soybeans, kidney beans, peas, etc.