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We have tested the microwave device of continuous operation for the thermal treatment of plant materials, which was developed and designed to implement microwave technologies in the industry. The purpose of the tests was to assess the effectiveness of the microwave device by the indicators of quality of the obtained material and energy consumption determined by the efficiency of the conversion of microwave energy into the internal energy of the material. The effects of microwave treatment of a straw substrate for tree-destroying fungi were studied. The treatment quality was determined by the yield of Oyster (Pleurotus) mushrooms, grown on the obtained substrate. Microwave treatment was carried out in various modes, which differed in the value of specific power. When analyzing the effectiveness of microwave treatment, the results were compared with the data obtained during the application of the traditional technology of straw sterilization. It was shown that the harvest of Oyster mushrooms increased by 11%. It was found that under the optimal mode, specific power was qv=8.68·105W/m3, final temperature was t=96°С, duration of treatment was 180 s. Based on the thermal calculations, the values of the microwave chamber efficiency ηcwere calculated; under the optimal mode, ηc=62%. The influence of the microwave treatment on the sowing characteristics of seed wheat grain was studied. The effectiveness of the microwave treatment was determined by the values of laboratory germination and seed germination energy. Under the optimal mode, the output power of magnetrons was ΣPout=0.6kW, the grain consumption was G=2.1·10-2kg/s. The study of the microwave device operation showed that for this design, in order to ensure stable and uniform movement of the material along the product pipeline, it is necessary to maintain the movement speed that is not higher than 0.5 m/min. It is recommended to apply the tested microwave device of continuous operation on specialized farms

We present results of experimental work on studying the drying of a dense layer of grain using microwave heating. We investigated a series of techniques to supply heat to grain to assess energy efficiency of a microwave field. We studied the following ways of drying: a microwave method, a pulsating microwave method, a microwave-convective cyclic method with blow of a layer with heated air flow and air without preheating, simultaneous microwave-convective drying method. Studying the kinetics of drying in a microwave field showed that we can divide the process into heating periods (zero drying rate), constant (first drying rate) and falling (second drying rate). These periods are characteristic for drying of colloidal capillary-porous bodies at other methods of heat supply. We obtained empirical relationships for the drying rate and the average temperature of grain in the first period based on the generalization of experimental data on the study on drying of grain of buckwheat, barley, oats, and wheat. We presented kinetic dependences in a dimensionless form. They summarize data on the studied grains. The aim of comprehensive studies of various methods of heat supply during drying was determination of the optimal method and rational operational parameters, which ensure high intensity of the process and the required quality of the finished product with minimal energy consumption. All studies took place under identical conditions and for the same grain (oats) to ensure the accuracy of the comparison. We determined that the most preferable method is a simultaneous microwave-convective energy supply without air preheating, which minimizes specific energy consumption. Experimental studies on drying using a microwave field made possible to select the required process parameters: power, heating rate, mass, and form of loading. We plan to develop a technology for drying of grain using microwave energy based on the study data