【摘要】 本文用空气-水系统,在φ1.2m的圆塔上研究了喷嘴孔垂直筛板塔盘(喷嘴孔VST)的流体力学性能,考察了各种几何因素和流体力学条件对塔板压降、漏液、气速下限、雾沫夹带和气速上限等参数的影响,获得了相应的关联式.在φ100mm的塔上,用乙醇-水系统测定了喷嘴孔VST的板效率,并与筛板搭进行了比较.更多还原

【Abstract】 Hydrodynamic and mass transfer charateristics of a new VST with nozzle-type vapour riser were studied in a circular column of 1.2m with air-water system. The influences of various geometric factors and hydrodynamic conditions upon the tray pressure drop, weeping and the lower limit of gas velocity andentrainment and upper limit of gas velocity were examined. The tray efficiency of the new VST was studied with ethanol-water system and was compared with that of sieve tray. The results are shown as below:1. The wet pressure drop over the tray is the sum of dry pressure drop and pressure drop caused by gas phase passing through liquid layer.The pressure drops of the new VST with the nozzle-type vapour riser are 40% less than those of conventional VST operating under the same conditions.2. The amount of weeping can be correlated by the following equation:3. Entrainment isthe upper limit of allowable gas velocity depends on the condition of gas escaping from the slat between cap and tray.更多还原