Tower equipment is an important production equipment widely used in chemical, petroleum and other industries. The basic function of tower equipment is to provide opportunities for gas and liquid phases to fully contact, so that the mass and heat transfer processes can be carried out quickly and effectively; In addition, the gas and liquid phases after contact can be separated in time without entrainment. Therefore, distillation and absorption operations can be carried out in the same equipment. According to the structural type of gas-liquid contact parts in the tower, the tower equipment can be divided into two categories: plate tower and packed tower. Several layers of trays (or trays) are installed in the plate tower along the tower height. The liquid flows from the top to the bottom by gravity, and a flowing liquid layer is formed on each plate surface; The gas is pushed by the pressure difference, passing through the liquid layer on each tray from the bottom of the tower to the top of the tower. The gas and liquid phases are contacted step by step in the tower, and the composition of the two phases changes step by step along the tower height.

The packed tower is filled with various forms of solid filler, namely filler. The liquid phase is distributed on the packing layer by the tower top spray device and flows down along the packing surface by gravity; The gas phase is pushed by the pressure difference through the gap of the packing and flows from one end of the tower to the other end. Gas and liquid contact on the wetted surface of the filler, and their composition changes continuously along the tower height.

In industrial production, plate tower is often used when the treatment capacity is large, while packed tower is often used when the treatment capacity is small. The scale of distillation operation is often large, and the required tower diameter is often more than one meter, so more plate towers are used; The scale of absorption operation is generally small, so more packed towers are used.