Generally speaking, the mass transfer efficiency is higher than that of bulk packing-this is from the perspective of mass transfer efficiency, the packing is a type of chemical substance and mass transfer equipment, mainly used in the benzene washing tower and ammonia washing in the recovery workshop of the coking plant Tower desulfurization tower and distillation tower for tar processing, industrial naphthalene distillation. The choice of filler is directly related to the product quality of the user. Let's talk about some factors to be considered in the selection of fillers (including determining the type, specification and material of the filler, etc.). The selected filler must not only meet the requirements of the production process, but also make the equipment investment and operating costs low.
Selection of filler types
The choice of filler type should consider the requirements of the separation process, usually considering the following aspects:
1. The mass transfer efficiency should be high.
2. The flux should be large. Under the premise of ensuring high mass transfer efficiency, packing with high flooding point gas velocity or gas phase kinetic energy factor should be selected.
3. The pressure of the packing layer should be low.
4. The packing has strong anti-fouling and blocking performance, and is convenient for disassembly, assembly and maintenance.
Selection of packing specifications
Packing specification refers to the nominal size or surface area of the packing.
1. Selection of bulk packing specifications The bulk packing commonly used in industrial towers mainly has several specifications such as DN16DN25DN38DN50DN76. For similar packing, the smaller the size, the higher the separation efficiency, but the resistance increases, the flux decreases, and the packing cost also increases a lot. However, when large-size packing is used in a small-diameter tower, poor liquid distribution and severe wall flow will occur, which reduces the separation efficiency of the tower. Therefore, there must be a regulation on the ratio of the tower diameter to the packing size. Generally, the ratio D/d of the tower diameter to the nominal diameter of the packing should be greater than 8
2. Selection of structured packing specifications There are many ways of expressing the types and specifications of structured packing commonly used in the industry. It is customary to express by specific surface area. There are mainly several specifications such as 125,150,250,350,500,700. The same type of structured packing has a larger specific surface area. The higher the mass transfer efficiency, but the resistance increases, the flux decreases, and the packing cost also increases significantly. When selecting, comprehensive consideration should be given to separation requirements, flux requirements, site conditions, material properties and equipment investment, operating costs, etc., so that the selected packing can not only meet the technical requirements, but also have economic rationality. There is also a packing tower worth mentioning that you can choose the same type of packing, the same specification, or the same type of different specifications; you can choose the same type of packing, or you can choose different types of packing; some towers Structured packing can be used for the section, while bulk packing can be used for some tower sections. The design should be flexibly mastered, and the packing specifications should be selected according to the principle of technical and economic unity.