The Study And Application Of A Movable Agricultural Wet Grain Ventilating Granary

This paper designed an agricultural wet grain ventilating and drying granary to solve the wet grain drying problems the farmers faced. The granary was based on mechanical ventilation and drying theory, which could dry wet grain about 2.5 t at a time. It was easy to operate and the grain could get out of the granary by itself. Besides, the granary was removable and multi-purpose, which could also dry rehmannia and other economic crops when it was added an auxiliary orifice and heating device.To verify the rationality of the design parameters of ventilating and drying granary, and provide theoretical basis for wet grain drying of ventilating and drying granary,this part studied the drying characteristics of high moisture content of wheat, corn, paddy which were at different temperature, in different moisture content and different grain thickness, and compared the quality changes of wet grains after drying, obtaining the optimum condition of the low temperature drying grain which were in high moisture. The results showed that the drying curve of wheat, corn, paddy of different temperature, initial moisture content, grain layer thickness fitted the exponential equation well, the influence degree of every factor on the rate of drying was: temperature>grain layer thickness>initial moisture content. In the process of drying, temperature was the main factor for the drying rate and drying quality. When the drying temperature of wheat, corn, paddy respectively were 45℃, 35℃ and 32℃, the wet grains were with higher drying rate and good drying quality. The higher the initial moisture content was, the worse the quality.In order to further improve the design parameters of the ventilating and drying granary, and verify its practicability, drying experiments of high moisture content corn and paddy were carried out in the ventilating granary. The results showed that when ventilating and drying experiments of high moisture content of corn and paddy were carried out in the ventilating granary, wet grain moisture content decreased according to the exponential equation. During the 40 hours of ventilation, the paddy which weighed 2100 kg and had 17.40% of moisture content could be dried to 12.49%, and during the 36 hours ventilation, the corn which weighed 2400 kg and had 15.90% of moisture content could be dried to 13.72%. The drying uniformity was well, and the quality of paddy and corn were good after drying.To exploit new uses of the ventilating and drying granary and solve the farmers drying problems of agricultural materials, the expanding application drying experiment of the ventilating and drying granary was carried out by using fresh rehmannia as the raw material in Henan.The drying characters of fresh rehmannia were studied, and the expansion application process of the ventilating granary was also carried out. The results showed that when the fresh rehmannia were dried in the ventilating granary, four phases temperature control technology were used. The stage 1: temperature was 55~60℃ and drying time was 20~24 h; The stage 2: temperature was about 70℃ and drying time was 14~18h; The stage 3: temperature was about 60℃ and drying time was 24~26h; The stage 4: cooling down to room temperature. The drying rate of modified ventilating granary was high during drying rehmannia. The percent of pass was as high as 92.1% after drying, and it effectively improved the quality of dried rehmannia and the economic benefits of the farmers.A series of experiments had demonstrated that the ventilating granary had high practicability and it was worth of popularization and application in the rural areas.