Development of a two-stage cyclone

Abstract

The process of separating the transported material from the carrying gas flow in cyclones at grain-processing enterprises is studied. Feed production is accompanied by the formation of fine flour dust which is a valuable component of fermented feed. Aspiration systems of mini-fodder plants do not provide its full capture, which leads to contamination of the premises, as well as the loss of some of the product. During the analysis of designs and ways to improve centrifugal apparatuses, it was determined that installation of additional swirling devices in the cyclone exhaust pipe is promising for cleaning the air flow from fine dust. The design of cyclone with an additional stage of cleaning the air flow from fine flour dust in the outlet nozzle, used in the pneumatic conveying system of mini-fodder plant, is proposed. The diameter of the axial pipe socket is enlarged to accommodate the baffle cone and vortex funnel inside it. The diameter of the outlet nozzle should be smaller than the diameter of the upper base of the vortex funnel to reduce the fine fraction escape from the cyclone. An experimental unit was developed including a charging hopper, pneumatic receptor-diverter, material pipeline, cyclone, filter, and a suction fan. The material used was wheat grain with a moisture content of 16%, crushed on a hammer crusher with a hole diameter of 3 mm in the sieve. Comparative tests of the proposed cyclone with cyclones of the DC and SNT types were carried out, the results of which prove the effectiveness of the proposed design. In the investigated range (from 0.026 to 0.33 kg/s) the efficiency of the two-stage cyclone in feeding the transported material was higher than that of the commercially available discharger cyclones DC.