Pall ring packing is generally composed of an air cooling tower, a water cooling tower, a chiller and a water pump. It is set between the air compressor and the molecular sieve adsorber of the packing tower to reduce the air temperature and the content of the air entering the molecular sieve adsorber. water volume. Pall ring packing has the advantages of large flux, low resistance, high separation efficiency and large operating flexibility. Under the same pressure reduction, the processing capacity can be more than 50% larger than that of Raschig ring. At the same throughput, the pressure reduction can be reduced by half, and the mass transfer efficiency can be increased by about 20%.

       The filler mainly plays its role by occupying the volume. Due to the presence of the filler, the molecular chain of the matrix material can no longer occupy all the original space, so that the connected segments are immobilized to a certain extent, and may cause the matrix polymer. orientation. Due to the dimensional stability of fillers, in filled polymers, the movement of molecular chains in the interfacial region of the polymer is restricted, resulting in an increase in glass transition temperature, an increase in thermal deformation temperature, a decrease in shrinkage, and a decrease in elastic modulus, hardness, stiffness, Impact strength is improved.

       Pall ring packing function:

       1. Reduce the shrinkage rate of molded parts, improve the dimensional stability, surface finish, smoothness and flatness or mattness of products;

       2. It can meet different performance requirements, improve wear resistance, improve electrical conductivity and thermal conductivity, etc. Most of the fillers can improve the impact strength and compressive strength of the material, but cannot improve the tensile strength;

       3. It can improve the coloring effect of the pigment;

       4. Some fillers have good light stability and chemical resistance;

       5. It has a capacity-enhancing effect, which can reduce costs and improve the competitiveness of products in the market. Air-cooled towers and water-cooled towers use Pall rings as packing and are free-stacked. During mass transfer and heat transfer, the liquid flows down evenly from the top of the tower and flows in a film-like manner along the packing, while the gas rises from the bottom of the tower and passes through the packing (the specific surface area of ​​the packing reaches 80~110m2/m3) when it contacts the liquid film, heat and mass exchange.

       Compared with the sieve tray tower, the air pre-cooling system adopts the Pall ring packed tower, and has the following remarkable characteristics:

       (1) The ability of mass transfer and heat transfer is strong. The temperature difference between the air temperature of the air-cooling tower and the cold water entering the tower in the upper section can be less than 1°C, and a negative temperature difference of 4-5°C can be generated between the outlet water temperature of the water-cooling tower and the sewage nitrogen temperature entering the tower;

       (2) Since the accumulation void ratio reaches 94~95%, it is not easy to be blocked, and it is not easy to be selected to form foam entrainment, which is conducive to the operation of changing working conditions. After the air volume is increased, it is not easy to carry water;

       (3) The pressure drop is small, and the resistance of each meter of packing is about 10mm water column;

       (4) The water consumption of the air cooling tower can be reduced by 30%;

       (5) The cooling capacity of the chiller can be reduced. It can be turned off in winter, and the cooling capacity in summer can be reduced by 80%, making it possible to realize the air pre-cooling system without chiller;

       (6) Easy installation and low manufacturing cost;

       (7) Relatively low density (0.9kg/m3), resulting in light weight of the product.