为了开发高教合理的柑桔皮渣发酵-干燥成套设备,需要进行发酵柑桔皮渣的干燥机理分析、传热传质的研究.该文采用流化干燥方法对发酵柑桔皮渣的干燥进行试验研究,建立了小型的流化床干燥试验台,分析了风速、颗粒粒径、初始含水率等对发酵柑桔皮渣流化干燥过程中传热传质的影响.试验表明:流化床的传热传质性能与流体的物理性质、操作参数、颗粒本身的物理性质以及流化床的特性密切相关.试验结果表明,传热系数沿流化床床高增加而减小,在床高4～6 cm之间,传热系数减小的幅度较大；在风速、颗粒粒径、初始含水率3个影响因素中,风速对传热系数的影响最大,当风速从2.06 m/s增大到2.75 m/s时,床高2～4 cm区域的平均局部传热系数增大了近92％.根据试验结果建立了传热传质数学模型并获得了传热无因次准则方程式,为强化传热传质以提高干燥效果提供了理论依据.%It is necessary to research the heat and mass transfer law in drying process of the zymotic orange peel for the purpose of industrial production of the zymotic orange peel feed. A fluidized drying method was used to research the drying characteristics of zymotic orange peel, and the experimental equipment of fluidized bed drying was built, the influences of drying parameters, such as air velocity, particle diameters, the initial moisture content etc on heat and mass transfer were analyzed. The results indicated that the heat and mass transfer characteristics of the fluidized bed were affected by the flow velocity, operating conditions, the physical characteristics of the zymotic orange peel and the fluidized bed. The experiment results showed that the local heat transfer coefficient decreased with the increasing of fluidized bed height, especially at the height from 4 to 6 cm. The air velocity had bigger influence on the local heat transfer coefficient compared to that of particle diameter and initial moisture content. The average local heat transfer coefficient in the height from 2 to 4 cm of the fluidized bed increased by nearly 92% when the air velocity changed from 2.06 to 2.75 m/s. Based on the experiential data, an experiential mathematical model was built up, and the non-dimensional heat and mass transfer equation of the fluidized bed was obtained, which can be a theoretical referrence to improve the zymotic orange peel drying process.
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