Analysis of constructions of technical means for separating seeds by density
Authors: Volyk D. A. , Popadyuk I. S. , Stepanenko S. P. 
Published: December 2023

Purpose. To intensify the seed separation process based on density through the justification of a new separator design.
Methods. Conducting a literature and patent search to analyze the designs of grain-cleaning machines with combined action on grain using disruptive forces.
Results. The choice of fractionation characteristics, the sequence of placement, and the composition of working elements in technological lines should be given great importance during fractionation. The universality of the use of combined grain cleaning machines reduces their nomenclature and limits the possibilities of using individual working elements. The use of various physico-mechanical indicators in the division of grain material leads to obtaining fractions with different properties and possibilities for further use. In particular, the density of individual seeds (saturation, density) is an important characteristic by which the material is divided during seed preparation for sowing, since this characteristic has a direct impact on the energy of germination and the similarity of the plant. Division of grain material by seed density can only be carried out if the seeds are pre-calibrated. Currently, pneumatic tables, pneumatic vibrating tables, pneumatic separators and other machines with combined action on the seed are used for seed fractionation by density Since it is not always possible to separate the raw material into fractions by individual impurity types or to isolate individual fractions in a pure form due to its multicomponent nature, imperfect working elements, and constantly changing composition of the raw material, in most cases, fractions containing the same components as the original grain material, but in different proportions, are obtained in production.
In this regard, combined technical means should be used for fractionation processes, which will combine working elements (air channel, sieve, trier, etc.), but for optimal loading of each of them simultaneously with fractionation, flexible adjustment of the volume and quality of the obtained fractions depending on the condition of the original grain material is necessary. The need for such adjustment arises due to the continuously changing composition of the raw grain material.
Conclusions
1. Analysis of the designs of technical means for separating seeds by density shows that known machines have the same specific indicators and do not differ significantly in the principle of action on the material.
2. The necessity of determining the feasibility of grain material separation taking into account its physical and mechanical properties has been established.
3. To reduce the energy consumption of cleaning and separating grain material for the purpose of obtaining high-quality seeds, it is necessary to justify complex technological schemes considering the nature of the processed material.
4. Criteria for flexible control of quantity, volume of obtained fractions, their quality, and parameters for the real-time assessment of the technological process using automated systems have been determined.
5. New combined working tools for separation processes have been substantiated depending on the stage of grain material processing and its qualitative composition, leading to the development of new technical means based on division characteristics and multiple criteria.
6. It has been established that the development of flexible fractional cleaning and seed separation schemes based on density, as well as the assessment of the economic efficiency of applied technological and technical solutions, enable seed producers to reduce production costs and increase the profitability of the enterprise.
Keywords: separator, grain fractionation, sorting, pneumatic conveying, intensification of the partition process.