惰性粒子流化干燥机的研究

Fluidized bed drier with inert granules

惰性粒子流化干燥是流态化干燥的特殊形式 ,适用于溶液、悬浮液、粘性浆状物料等液相物料的干燥 ,其技术关键是粒子表面对物料的均匀吸附、流化效果和干燥物料的及时脱离。本研究在设有搅拌机构的流化床内装填惰性粒子 ,进而提高传热传质面积和速率 ,并将干燥与粉碎合二为一。试验设备接近于实际工况 ,采用当量直径为 4mm的聚四氟乙烯颗粒为惰性粒子 ,以浆状物料为干燥对象 ,着重研究惰性粒子流化干燥机的干燥机理和设备结构 ,以及对搅拌、雾化、投料、传热系数、开孔率等影响因子进行试验分析 ,并对重要的因素进行了数据回归分析 ,从而找出惰性粒子加入量与投料量之间的规律 。

Fluidized bed drying with inert granules, a special method of fluidized bed drying, may be used in the drying of liquid materials such as solutions, suspensions, and pasty materials with viscosity. The key techniques include uniform absorption of materials on the surface of the granules, the fluidized effect, and the in-time separation of dry materials. In this study inert granules were loaded in a fluid bed equipped with a stirring mechanism, which led to increases of both the area and the rate of heat and mass transfer, as well as the combining of the processes of drying and crushing. The experimental conditions were close to real-world conditions, in which the inert granules were made of polytetrafluoroethylene with an equivalent diameter of 4 millimeters. Pasty materials were selected for drying. Both mechanisms of drying, and equipment structure, have been highlighted for the fluidized bed drier with inert granules. The effects of stirring, atomizing, feeding, heat transfer coefficient, and the opening rate, have been analyzed in the experiments. Furthermore, data regression analysis was applied for the essential factors. Through this experiment the relationship between the quantity of inert granules and the feeding amount was studied, providing a foundation for the product design of a fluidized bed drier with inert granules.