复合塔板气液运动的实验研究

采用多路电导测试系统,在直径500mm的冷模塔内,以空气-水为试验物系,研究了开孔率20%和25%复合塔板上的气液运动规律.实验揭示了气液穿孔运动的三种状态通液、通气和阻塞,并对复合塔板的气液运动机理进行了阐述.实验考察了空塔动能因子F、喷淋密度LV和开孔率φ对通液率、通气率和阻塞率的影响,分析了筛孔真实气速与复合塔液泛点关系.结果表明F因子增大,通气率也增大,而通液率和阻塞率减小;喷淋密度增加, 通气率下降,通液率上升;开孔率较大,则通气率较小,通液率和阻塞率较大;在实验范围内(开孔率20%及25%、喷淋密度5～40m3·(m2·h)-1的情况),复合塔液泛点的筛孔真实气速在11m·s-1左右,为其它物系确定操作上限提供了依据.

Study on the Gas-liquid Performance of the Compound Tray

The gas-liquid performance of the compound tray with free area 20% and 25% respectively was investigated by multi-path conductometer. All runs were carried out in a 500mm diameter column with water-air system. Three states such as liquid flowing, gas flowing, and liquid blocked for the holes were put forward and the corresponding mechanism was clarified. The effects of factors including F parameter, liquid flow rate, and tray fractional free area on the holes ratio of three flowing state were studied, and the relations of the real gas velocity through the holes and the flooding point were discussed. Results show that gas flow ratio increases with the increase of F parameter and the decrease of liquid flow rate and tray fractional free area. Liquid flow ratio is the inverse of gas flow ratio; liquid blocked ratio increases with the increase of tray fractional free area and the decrease of F parameter. The real gas velocity in the holes at flooding point is about 11ms-1 under certain tray fractional free area (20%, 25%) and liquid flowing rate (5~40 m3(m2h)-1), according to these data, the operating up limit of compound tray for other gas-liquid system can be reckoned.