筛板塔中乙醇-水精馏板效率的研究

利用筛板塔对乙醇-水系统进行精馏实验。在室温冷进料、回流比为6:1,进料乙醇体积分数为35%～60%的条件下,改变进料板N位置(N=8,12,14),采集塔顶、塔底和进料的酒度计和温度计读数;对数据进行换算与处理,计算出精馏段操作线和进料方程,绘出进料线和精馏段操作线,绘出提馏段操作线和平衡线,利用计算和拟合方法绘出有效平衡线,在平衡线与操作线之间绘出理论板数,在有效平衡线与操作线之间绘出实际板数;计算并分析全塔和分段塔板效率。结果表明:第8块板进料时,精馏段板效率最高;第12块板进料时,全塔效率最高。有效平衡线的引入,使板效率分析清晰,为实际应用提供了实验数据和理论分析方法。

Research on Plate Efficiency of Ethanol-water Distillation in Sieve-plate Columns

Sieve-plate columns were applied to ethanol-water distillation. It was operated with the conditions of ambient temperature feeding, reflux ratio 6:1, feeding volume concentration between 35% and 60%, and feeding plate at N=8, 12, 14. Overhead product, bottom product and feed were determined by the oenometer and thermometer. On the basis of data-processing, operating line for the rectifying section and feeding line were worked out and plotted. Stripping section operating line and xy diagram were drawn, and effective equilibrium curve was worked out by the calculation and processing method. Theoretical plates were lined between xy diagram and operating lines, and practical plates were lined between effective equilibrium curve and operating lines. Plate efficiencies in the two sections and overall efficiencies were analysed. The results show that plate efficiencies in rectifying section was the highest with feeding at plate 8. The overall efficiencies was the highest with feeding at plate 12. The introduction of effective equilibrium curve made the plate efficiency analysis easy and clear. It contributed experimental data and theoretical methods to practical application.