协同加热除湿烘干机设计及对香菇烘干性能的测试

Design of drying machine with co-heating and dehumidification and testing of its drying performance on shiitake mushrooms

目的:提高香菇干燥效率、减少烘干耗电量。方法:设计了一种新型协同加热除湿烘干机,该烘干机以半导体制冷片为主要部件,其热端为热源加热空气用于烘干香菇,冷端为冷源用于冷凝水蒸气除水,整体采用封闭式设计;采用该设备测试了不同干燥温度(55,65℃)和样品质量(200,400 g)下的香菇烘干速率,并采用9种薄层数学干燥模型对干燥速率进行动力学模拟。结果:Midilli模型比其他模型能更好地预测干燥效果。温度越高,香菇颜色变化越大,收缩率越高。该烘干机的综合能效比达到1.96,烘干香菇的耗电量为81.21 MJ/kg。结论:采用试验机烘干的香菇水分含量、颜色变化等指标均符合国家标准,且与传统电加热烘干机比较,其节能效果显著。

Objective:In order to improve the mushroom drying efficiency and reduce the power consumption,a new type of co-heating and dehumidification drying machine was designed and built.Methods:The drying machine was a closed system,which took the semiconductor refrigeration piece as the main component,with its hot end as heat source for air pre-heating and its cold end as the cold source for water vapor condensation.On the device,the mushroom drying rate at different drying temperatures(55 and 65℃)and sample mass(200 and 400 g)were tested.Results:Nine thin layer mathematical drying models were used to simulate the drying rate,which revealed that the Midilli model had a better predict effect than the others.In addition,it was found that the higher drying temperature resulted in a greater color change and a higher shrinkage rate.The comprehensive energy efficiency ratio of the drying machine was 1.96,and the power consumption of drying mushroom was 81.21 MJ/kg.Conclusion:In the experiment,the indexes such as moisture content and color change of dried mushroom met the national standards,and the energy-saving effect was remarkable compared with the traditional electric heating drying machine.