Research On Hydrodynamics And Mass Transfer Of High Efficient Bubb-Cap Tray

In order to solve the problem of the traditional Bubble-Cap tray with the shortcoming ofcomplex structure,high entrainment and low tray efficiency, we proposed a new type of traycomposed with an improved Bubble-Cap tray and Bubble collecting net.Experiment wascarried out in air-wate-oxygen system in a1000mm×400mm organic glass tower, and thepressure drop,entrainment,weeping and tray efficiency of the tradition Bubble-Cap tray, theimproved Bubble-Cap tray, the improved Bubble-Cap tray with low opening rate, and traycomposed with the improved Bubble-Cap and Bubble collecting net(referred to type I, type II,type II with low opening rate, type III) were measured.From the experiment,We stuied theinfluences of gas-liquid flow, weir height, tray structure and opening rate.The experimental results show that, compared with the type I bubble cap tray, type II gota better hydrodynamics and tray efficiency: the pressure drop are20%~40%lower than type I,and the pressure drop inceased with the increase of F0,liquid flow and weir height, in a certainrange, increasd with the decrease of the opening rate; With the incease of F0,the inceasingtrend of entrainment was smaller than that of type I, Entrainment increasd with the increase ofliquid flow, weir height and opening rate; Weeping did not occur within the operating rangewhich convinced that the weeping point of type II was lower than that of type I; Trayefficiency of type II are10%higher than type I, with the increase of F0,tray efficiency showedthree stages, with the increase of liquid flow and weir height, tray efficiency increased firstand then decreased, with the decrease of opening rate, tray efficiency increased.Equipped withtwo layers of bubble collecting net,type III Bubble-Cap tray had little effect with the flow ofgas but can prevent the flow of liquid, though the pressure drop were higher than that of typeII, its entrainment decreasd effectively, the bubble collecting net can break bubble and atomizedroplets at the same time which increased the gas-liquid contact area so as to enhance the masstransfer efficiency, in a wide range of gas velocity, tray efficiency of type III can bemaintained at more than85%. The correlative equation based on the experiment data curve ofpressure drop, entrainment, weeping and tray efficiency can provide theoretical basis forengineering application.