WAYS OF IMPROVING THE DESIGN OF THE WALNUT CONVECTIVE DRYER

Abstract

Walnuts belong to the products most exposed to the risk of oxidative deterioration at the stages of storage, transportation and sale. At the same time, it should be taken into account that specific botanical varieties grown in different geographical regions have an individual chemical composition that determines the intensity of the ongoing oxidation processes, therefore nuts of different batches have different potential for storage. The lack of a system of traceability of purchased nut batches at the stages of production, logistics and sale, as well as the lack of objective methods for assessing the potential level of preservation, which leads to the incorrect establishment of the expiration dates of walnuts, and as a result, more than 30% are sold in trade networks walnuts with signs of bitterness. The quality of nuts during storage depends mainly on the moisture content, storage temperature, relative humidity, oxygen content level, commercial type of nuts, packaging materials, storage form and type of technological processing of nuts (without shell, in shell, fried, etc.). Nuts are products of long-term storage. The purpose of the research is a comprehensive analysis of the operation of modern convective dryers of agricultural raw materials and the determination of ways to improve them to ensure high-quality and uniform drying. According to the results of the analysis of the existing drying units, their disadvantages and advantages were determined. The peculiarities of the application of hopper dryers in various production lines among industrial goods, food products, and construction materials that require mixing of bulk products are analyzed. The use of these dryers has shown high reliability in operation when drying significant volumes of raw materials, absence of stagnant zones, high efficiency of the process and automation of the entire technological process of drying. In order to intensify the process of convective drying, it is necessary to improve the heat and mass transfer both inside and outside the raw material, an increase in the drying temperature will inevitably lead to overheating of the product and loss of biologically useful substances, so one of the ways to increase the drying speed can be the use of mixing devices and devices , installed inside the drying chamber.