Development of pneumatic separator with a ring multi-tiered aspiration channel

Abstract

Air separation is widely used in modern technologies of post-harvest grain handling. Pneumatic separating channels of various types are used in pneumatic separators, both as a separate air machine and as part of air-sieve grain cleaning machines. Recently, annular pneumatic channels have been increasingly used. They have high performance, and the air flow speeds in the separation zone can be higher than in rectangular aspiration channels. In modern grain cleaning machines, to separate grain material, as practice shows, differences in the components of a grain heap are widely used, mainly in terms of sailing capacity and size. Long-term studies have revealed that during preliminary cleaning it is most advisable to separate the grain material by sailing capacity, since the separation of light components at the first stage of cleaning facilitates the subsequent operation of the sieve pans. When preparing seeds, at the final cleaning stage, air separation is used for grading. Based on the results of the analysis of the aspiration systems of grain cleaning machines, it was found that the most promising direction was the development of annular pneumatic separating channels. The separation process in such channels may be intensified due to the oncoming movement of the air flow and the processed material. By thin-layer feeding grain material into the separation zone and then repeatedly exposing it to air flow, the separation efficiency may be increased. An air separator with a multi-tiered annular aspiration channel is proposed, and the main design and operating parameters are calculated.