澳洲坚果中红外干燥机设计与试验

针对澳洲坚果干燥时间长、能耗大等问题,设计了中红外干燥机,分析澳洲坚果干燥水分与速率变化规律,探明干燥水分扩散与活化能变化机制,运用1Stopt软件对典型干燥模型进行数据拟合并建立中红外干燥模型。结果表明,采用加热腔内60℃,中红外发射管0.8kW的干燥条件,经过360min果仁含水量降至1.36%的安全水分,整个干燥阶段主要为降速干燥,Midilli-Kucuk模型可以有效预测澳洲坚果在中红外干燥过程中水分的变化机制,各时段澳洲坚果的有效水分扩散系数在2.03×10-7~2.31×10-7 m2/s,利用阿伦尼乌斯公式计算出澳洲坚果的干燥活化能为159.5kJ/mol。

Design and experiment of mid-infrared dryer for macadamianut

In view of the problem of long time and high energy consumption of macadamia nuts of drying,the infrared drying characteristics were analyzed and a mid-infrared dryer was designed.The mid-infrared drying characteristics reasch of macadamia nuts were carried out.The changes of dry moisture and rate were analyzed.The dry-diffusion and activation energy conditions were established and a mid-infrared drying model was established.The results showed that the moisture content of macadamia nuts decreased to 1.36% after 360 minutes under the drying conditions of 60 ℃ and 0.8 kW in the middle infrared emitter.The whole drying stage was mainly slow drying.The Mi-dilli-Kucuk model could effectively predict the moisture change mechanism of macadamia nuts in the middle infrared drying process and the Australian firmness in each period.The effective water diffusion coefficient was between 2.03×10-7 and 2.31×10-7 m2/s.The drying activation energy of macadamia nuts was calculated by Arrhenius formula.