Overview of Methods and Tools for Drying Walnuts in the Shell

A necessary condition for obtaining a high-quality walnut is its timely drying with bringing it to the standard humidity while maintaining the required quality of the product. Currently, Ukraine does not have a sufficient number of highly efficient lines for the industrial processing of walnuts. The main problem is precisely the lack of high-performance, energy-efficient drying equipment. In practice, dryers of various designs are used for industrial drying of walnuts. The choice of drying equipment depends on a number of factors, such as the volume of products, meteorological conditions during harvesting, availability of energy resources, etc. In most cases, two types of dryers are used for drying walnuts - convective and radiation. Convective dryers have a significant advantage in terms of the possibility of intensifying the drying process. One of the possible ways of intensifying the process is the use of vibration to reduce the aerodynamic resistance of the material layer, which has a positive effect on the energy indicators of the process, and to increase the uniformity of the moisture content of the drying material. The authors proposed a design scheme of a convective-vibration dryer that will organically combine the advantages of the convective drying method with the possibility of intensification of the process through the vibration effect on the material layer. The design of the drying unit allows you to easily control the main mode parameters of its operation: the flow rate and temperature of the drying agent, as well as the parameters of the vibration effect - the frequency and amplitude of the oscillation of the drying container. This is very important for the practical implementation of the nut drying process. After all, the rational selection of these parameters will allow the process of drying walnuts to be implemented with maximum efficiency. The practical implementation of the process of drying walnuts in the shell on this dryer will confirm the innovative approaches included in its design.

Justification of the Method of Drying Walnuts

Tsurkan,

Spirin,

Tverdokhlib

et al. 2023

Walnut Processing Technology

Kaletnіk,

Tsurkan,

Spirin

et al. 2024

Walnuts are currently a unique product, the components of which are used in the food industry, the production of medical and cosmetic products, the production of building materials, as an energy product and in other areas of activity. Ukraine is one of the leading producers of walnuts, but most of them are offered in the shell. The maximum economic efficiency of walnut processing technology is achieved through the use of a full cycle of processing and the use of all components: pericarp, kernels, shells, membranes. Therefore, the development of an energy-efficient line for a full cycle of walnut processing is currently very relevant for this promising branch of agriculture. Analysis of recent studies and publications shows that the attention of researchers and practitioners in most cases is directed to solving individual problems that arise before them, that is, individual technological processes and operations have been studied. Namely, the complete processing of sins ensures the maximum profit from their cultivation. In this work, the authors set a goal to develop a technology for processing walnuts that would provide the most complete cycle of their processing, which will provide, accordingly, the maximum profit from its implementation. The technology of complete processing of walnuts involves the use of a significant number of different machines that use different types of energy. For more efficient use of energy, it is recommended to use measures and means that intensify technological processes. In particular, an effective means of intensifying technological processes is the vibration effect on the processed material. This is especially true for the drying operation, because the implementation of this operation requires almost half of all the energy consumed in the technology. The technology also involves the use of non-traditional energy sources.

Method of Measuring Ozone Concentration During Drying of Walnuts in a Vibratory Dryer

Tsurkan,

Spirin,

Prysiazhniuk

et al. 2024

From a botanical point of view, walnuts belong to the genus Juglans, which has more than 20 different species. The name of this genus comes from the Latin phrase "iovis glans", which translates as "Jupiter's acorn". Walnut kernels are used in many industries - in medicine, food and perfume industries. With the addition of hard fruit shells, the technological process of tanning leather is carried out. The pericarp, due to its high iodine content, is used to dye fabrics in various shades of brown, as well as for medical purposes. Walnut shells are used to make activated carbon, grinding stones, linoleum, etc. Currently, Ukraine occupies the sixth-eighth position in the world ranking in terms of walnut cultivation, production and export. Over the past 30 years, an average of almost 90,000 tons of nuts have been produced per year. China is the world's leading producer and exporter of walnuts in shell, with over 705,000 tons per year. The top three countries are the United States and Iran, with over 405,000 tons and 256,000 tons respectively. Turkey, Burkina Faso and Mexico are also among the world's leading producers of walnuts. Almost 60% of walnuts in shell are grown and produced in Asia, 25.5% in South and North America. Europe produces 14.4%, Africa 3% [1-3]. Based on the results of previous studies, which established the prospects for using vibration effects on the processed medium during drying, as well as ozone during dehumidification of various agricultural raw materials, we developed the idea of combining vibration technologies and ozonation, which we implemented in a vibration dryer for processing walnuts with an ozone-air mixture.