Effective methods and techniques for drying tobacco leaves using solar energy in Kyrgyzstan

Abstract

In the Kyrgyz Republic, labor-intensive hand methods of harvesting and stringing tobacco leaves on cords for sun-curing are mainly used, and sun-curing depends on the weather conditions. Uncontrolled drying of the tobacco leaf plate and color fixation due to the indefinite duration of sun-curing, do not ensure the curing process under optimal conditions. Economically unfavorable under the conditions of the Kyrgyz Republic is artificial drying - flue cure and solid drying when labor costs reach from 347 to 653 man-hours per ton; and specific fuel consumption is from 1.014 to 2.0 t per t. Taking into account the above under the natural and climatic conditions of Kyrgyzstan where during the drying period of the 1st, 2nd, 3rd, 4th and 5th picking (June-September), the average daily air temperature fluctuates in the range of 20....26°C, and the maximum from 28 to 38°C, it is quite possible to carry out curing the leaf blades of the mentioned pickings under natural conditions without artificial heating. Midrib completing drying should be carried out in the completing drying chamber using the heat of solar energy obtained from solar collectors. Therefore, the most rational way of tobacco curing under the natural and climatic conditions of Central Asia and Kyrgyzstan is natural curing (sun-curing under film) and on mechanized production lines with 100% use of solar heat which contributes to the mechanization of all types of technological operations performed during the post-harvest handling of tobacco. At the same time, the use of the innovative tobacco cultivation technology increases profit from 1 hectare by 13 thousand KGS while labor costs for the production of 100 kg of raw materials are reduced from 21.1 to 18.8 man-days.