New types of air heating solar collectors and their use in drying agricultural products

Abstract

The aim of this research was to make new types of air heating solar collection for agricultural production drying and check their operation. In 2011 and 2012 were obtained two Latvian Republic Patents for air heating solar collectors. One for an autonomous, compact air- heating solar collector, the other one for a cylindrical crop production drying device with solar collector that can be used for drying products. So there are two different types of drying facilities with solar collectors using sun-warmed air: cylindrical crop production drying device, and autonomous, compact crop production drying facility. Cylindrical facility is tested for drying 19.5% wet wheat. Autonomous, compact crop production drying facility is tested for fresh carrots and apples 5-10 mm slices drying, using ambient air, heated with the solar collector. For experimental results on carrot and apple slices the layers of humidity and temperature changes in the drying process are given. Grain temperature distribution in wet wheat layers during drying with heated ambient air depending from sun radiation is given.