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Study on Drying Technology of Thomson Seedless, Jujube and Apricot with the Equipment of Drying Fruits and Vegetables by Series Parallel Solar Energy

Author: LiuYiJian
Tutor: WangZuo；WangHai
School: Agricultural University of Hebei
Course: Agricultural Products Processing and Storage
Keywords: Fruit dried Solar Equipment Drying curve Mechanism Raisins Hami Jujube Apricot
CLC: TS255
Type: Master's thesis
Year: 2009
Downloads: 81
Quote: 0
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Abstract

Solar drying is an energy-saving method of drying methods of fruits and vegetables. In this paper, a self-developed hybrid solar collectors fruit and vegetable drying equipment as the main raw material, Xinjiang seedless white grapes, Hami jujube and apricot, seedless, of Hami Jujube and dried apricots manufacturing process device inlet temperature, outlet temperature, ambient temperature, and the variation of the temperature of the drying room; relative humidity equipment imports, exports relative humidity, ambient relative humidity and dry room relative humidity variation; seedless white grapes, Hami of jujube and apricot moisture content variation of wind speed variation; equipment exports. Seedless white grapes, Hami jujube and apricot drying process, and a preliminary analysis of its drying mechanism. The main findings are as follows: seedless dry test results: (1) the period from September 18 to October 17, the average temperature of the equipment imports relative ambient temperature increased 18.5 ℃, room temperature relative natural air rises 21.1 ℃, the average temperature difference of Equipment Import and Export 8.5 ℃, equipment collectors effects significantly, the substantial increase in the use of solar energy. Device inlet temperature gt; the temperature equipment exports gt; ambient temperature gt; hanging room temperature, ambient relative humidity lt; the the device exports relative humidity lt; the the equipment imports relative humidity lt; hanging room relative humidity, drying equipment seedless cycle lt; environmental the naturally drying cycles lt; hanging room drying cycle. Seedless grapes drying cycle for 15d, drying equipment from flies, dust contamination, drying quality has greatly improved, Seedless raisins superior grade rate Hami region average of 35% to 79.19%. Fruit and vegetable drying equipment loading fresh grapes about 3t, seedless raisins dry finished about 0.75t. (2) Hami region September temperatures significantly higher than in October, the best time of seedless white grapes dry September. (3) the import of equipment at the wind speed trends: measuring time first increased and then decreased, temperature, pressure, wind speed becomes larger, the lower the temperature, wind speed decreased. (4) the drying rate curves of seedless grapes, reflecting the change of the rate of drying in the drying process is divided into three stages, the moisture content changed from 77% to 74%, for the adjustment phase; moisture content changes from 74% to 51%, constant speed phase; moisture content from 51% to 25% of the deceleration stage drying rate gradually decreased until the end of drying. Hami jujube dried test results: (1) September 11, 2008 to October 2, Hami jujube drying time of 21 days, the device inlet temperature gt; temperature of the equipment exports gt; ambient temperature, relative humidity lt; equipment exports relative humidity lt; equipment imports relative humidity. (2) during the measurement equipment import and export average temperature difference of 3.8 ° C. Because the harvest period, jujube and seedless with equipment oven drying. Hami jujube dried is placed on the tray, and seedless white grapes drying when compared to the fan guide into the air resistance is much much smaller, so the relatively low utilization of hot air. Equipment imported at wind speed changes with seedless variation. (3) Hami jujube drying time was significantly shortened, the quality is much improved. Jujube the moisture content variation curve, which reflects the change in the rate of drying in the drying process. Jujube the moisture content reduces from 64% to 14%. The drying curve is divided into three stages, the moisture content changes from 64% to 61%, this adjustment phase; change from 59% to 48% of this is mainly to go unless combined with water and gradually increase the drying rate; from 48% dropped to 14% for the spin-down phase. Dried apricot test results: (1) June 20, 2008 to July 2, apricot drying time of 12 days, the equipment inlet temperature gt; device temperature exports gt; ambient temperature, ambient relative humidity lt; equipment exports Relative humidity lt; the equipment imports relative humidity. (2) during the measurement equipment import and export average temperature difference of 0.7 ° C. Equipment drying oven, hot air blower import greater the resistance, the higher utilization of heat, is better than that of the equipment drying Thompson Seedless grapes tray drying jujube and apricot. Equipment imported at wind speed changes with seedless variation. (3) apricot moisture content curves, reflecting the trend of changes in the moisture content in the drying process. The moisture content is reduced to 15% from 78% of the fresh apricot. Apricot drying process is relatively flat, mainly in three phases, the moisture content from 78% to 75%, the drying stage of adjustment, the moisture content from 75% to 62%, the drying rate gradually stabilizing, 62% to 15% of the deceleration stage . The test, test-Hybrid fruit and vegetable drying equipment, provides a theoretical basis for the future for the device has laid a solid foundation for the further promotion in Xinjiang.

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CLC: > Industrial Technology > Light industry,handicrafts > Food Industry > Fruits, vegetables,nuts processing industry
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