直管式气流干燥器干燥褐煤的试验研究

阐述了褐煤干燥加工的意义及对洁净煤技术发展的影响,分析了褐煤水分的赋存状态及脱除特性,并根据气流干燥的原理,开发设计了直管式气流干燥器试验装置。通过分析系统运行温度数据,认为:整个干燥过程分为加速干燥阶段和等速干燥阶段,加速阶段的距离占整个干燥器总长度的20%,传热量占整个干燥过程传热量的70%;等速阶段的距离占整个干燥器总长度的80%,传热量占整个干燥过程传热量的30%。根据试验结论,提出了直管式气流干燥器长度两段计算法,同时结合系统运行工况,建立了试验线数值模型,并对试验结果进行了预测。

Experimental Study on Straight-tube Air Dryer Drying Lignitic Coal

This paper analyzed moisture stand-by condition and its de-watering feature of lignitic coal,and based on principle of air flow drying,design and developed straight-tube air dryer.Through analyzed the operation temperature of system,showed that the total drying process was divided into acceleration drying stage and constant-rate drying stage,the length of acceleration drying stage is 20% of the total length of dryer,and rate of heat transfer is 70% of that of total;the length of constant-rate drying stage is 80% of total length of dryer,and rate of heat transfer is 30% of that of total.According to the test result,presents the two stage calculation method for straight-tube dryer;combined with the system operation condition,established the test numerical model and prospected the test result.