椰蓉微波流化床组合干燥动力学

摘要

采用微波流化床组合干燥的方法对椰蓉进行脱水干燥研究.实验测定了流化气速在1.3 m/s时,不同微波输出功率密度、不同进风温度下椰蓉微波流化床组合干燥曲线,并确定椰蓉干燥动力学模型.结果表明:微波输出功率密度和进风温度对椰蓉干燥过程水分的下降影响显著,微波输出功率密度越大,进风温度越高,椰蓉水分下降越快.椰蓉微波流化床组合干燥过程符合Page模型MR＝exp(-K tN),其中 K＝2.06exp[(-3.39×104+1 814 P)/(RT)],N＝1.7,该模型可以很好地模拟不同条件下干燥过程中椰蓉水分随时间变化的规律.%A microwave-fluidized bed was used to a coconut drying to research the variation of moisture ratio at microwave output power density and different inlet air temperatures in the microwave fluidized bed.The coconut drying kinetics model was also established.The results showed that high inlet air temperature and great microwave output power density had significant impact on the coconut drying process,which led to a faster moisture rate falling.The microwave-fluidized bed drying process was fit in the Page model.The variation of moisture ratio of the coconut could be well simulated by the drying kinetics model MR＝ exp(-K tN),K＝ 2.06exp[(-3.39×104+1 814 P)/(RT)],N＝1.7.