高热效率节能两级干燥工艺的研究

简述了高热效率节能两级干燥工艺流程利用余热的基本原理。经过热平衡分析,推导出单位水分汽化耗热空气量、耗热量和每千克热干空气汽化水分的能力与热风温度和尾气温度的函数关系,绘制出函数曲线图,并算出降低尾气温度的节能效果。用于指导现在所有热风干燥机提高热效率,具有明显的经济效益。在两级气流干燥机上应用,热效率高达80％～88％,节省热能20％～40％;在沸腾床上干燥玉米胚芽,两级干燥节省煤、电45％,提高效率45％。

A STUDY ON HIGH EFFICIENCY ENERGY-SAVING TWO-STAGE DRYING TECHNOLOGY

This paper briefly described the basic principle of the High Thermal Efficiency Energy-saving Two-stage Drying Technology which utilizes the waste heat. Through heat balance analysis, the functional relationship of air requirement to evaporate 1 kg water, heat consumption, water evaporated by 1 kg dry air to air temperature and exhaust temperature were derived, and the related functional curves were drawn. Finally, the energy-saving efficiency by lowering exhaust temperature was calculated. The analysed results can be used as a directory to improve the thermal efficiency of hot air dryer.Flash dryer using the principle has thermal efficiency of 80%-88%,or it can save about 20%-40% energy compared with the conventional flash dryer.The fluidized bed dryer, using the same principle to dry corn germ, can save 45% heat energy.