The purpose of the liquid distributor is to evenly distribute or redistribute the liquid on the top of the packing or at a certain height, so as to improve the effective surface of mass transfer and heat transfer, improve the interphase contact, and thus improve the efficiency of the tower.The experimental results show that the liquid flow in the packing layer is not uniform, but exists gully flow, bias flow and wall flow. This will cause the amplification effect and end effect of the packed tower. The reasonable design and selection of liquid initial distributor and redistributor is aimed at reducing and preventing the amplification effect of the packed tower, thus reducing the height and diameter of the tower and reducing the cost or operation cost.