RESEARCH OF ENERGY EFFICIENCY OF GRAIN RAW MATERIALS DRYING USING VIBRO-OZONE COMPLEX

Abstract

In the system of technological operations of postharvest processing of grain the most important place belongs to drying. Quality drying not only ensures the storage of the harvested crop, prevents its loss, but in some cases also improves the quality of the finished product. It is at this stage that up to 80% of the total energy of post-harvest grain processing is consumed, and the useful use of energy in the grain dryers themselves is up to 40-45%. The direction of improvement of grain drying technologies are: reduction of energy costs for moisture removal, ensuring environmental safety of the dried product, development of highly efficient grain drying equipment. Significant intensification of the grain drying process can be achieved by using vibration on the processed material with simultaneous ozone treatment as part of the drying agent, which further reduces the energy consumption of the operation and allows to obtain a high quality final material. In the article the energy efficiency of drying of grain raw materials with the use of vibro-ozone complex depending on the mode parameters of the studied process is experimentally investigated and rational parameters of the developed equipment are received. Based on the obtained data, it was determined that the specific energy consumption per unit of finished product with moisture content Wf=14% at initial moisture content is: when using the classical technology with the supply of a heat agent at a temperature of 50 oC with a processing time of 240 minutes – 112,93 Wh/kg or 18,82 Wh/kg per 1% of evaporated moisture (406,54 KJ/kg or 67,75 KJ/kg per 1% of evaporated moisture); when using a complex thermophysical effect with a processing time of 160 minutes – 91,01 Wh/kg or 15,16 Wh/kg per 1% moisture evaporated (327,63 kJ/kg or 54,6 kJ/kg per 1% moisture evaporated). Experimental studies made it possible to obtain compromise technological parameters of the investigated process of drying grain raw materials using a vibro-ozone complex, the following components: vibration acceleration a=15-20 m/s2, drying agent temperature TDA=50-55 oC, ozone concentration = 8-10 mg/m3, processing time tP=130-160 minutes with the speed of the drying agent 1,5 m/s.