Pall ring packing

The use of Pall ring packing can have larger surface area and void ratio, increase the uniform distribution of fluid, change the range of liquid spray density, and enhance the effect of mass transfer. Now put forward some opinions on the construction and transformation of domestic Pall ring packing: 1. In response to the national call for energy conservation and emission reduction, and reducing production costs for enterprises, the application of Pall ring packed towers will inevitably increase enterprise benefits and achieve the purpose of rational use of energy. 2. The technical feature of the Pall ring packed tower is the material and shape of the packing. When choosing Pall ring packing, attention should be paid to the choice of packing, once the material or installation of Pall ring has problems, it will greatly affect the rectification effect. The thermal stability of Plastic Pall Ring Packing material is not good, but its corrosion resistance, small mass and excellent processing performance. Metal Pall ring packing addresses poor thermal stability properties, but is susceptible to corrosion. Ceramic Pall ring packing can solve both temperature problems and corrosion problems, but its brittleness and weight are its disadvantages. Type bulk Pall ring packing is easy to process, pack and clean, but it is difficult to control maximum wetting of the packing. The equipment investment of structured Pall ring packing suitable for most separations is much higher than that of bulk packing. 3. When installing the Pall ring packed tower, it is not only necessary to ensure the initial distribution of the liquid is uniform, but also to ensure the liquid distribution of the entire Pall ring packed tower. This problem can be solved by adding a liquid redistribution device. Good liquid distribution can increase the free cross-sectional area of gas passage, reduce gas passage resistance, increase operating flexibility, and reduce foaming and mist entrainment. 4. With the continuous development of Pall ring packed towers, the gas distribution problem, which was neglected before, has gradually been paid attention to. In the case that the conventional device cannot meet the uniform flow of gas into the bed, a grid should be installed in the Pall ring packed tower to improve the mass transfer efficiency. 5. Other tower components of the Pall ring packing such as the support plate of the packing layer, the pressure plate, the full-section liquid collector at the packing section, and the redistributor are also important components to ensure the energy efficiency of the tower, and they should also be paid great attention. 6. When the material enters the Pall ring distillation column, it cannot be supercooled and overheated. Since there is very little liquid phase retained in the Pall ring packed tower, some of the tower sections are simply used for heat exchange and lose their separation ability, which affects the separation effect of the entire tower. 7. When transforming the old tower with side feed or discharge, pay attention to the process conditions. After the transformation, the position of each side line must be aligned with the corresponding point in the vertical concentration distribution of the tower, in order to ensure the composition of the incoming and outgoing materials of each side line, which is difficult to achieve. 8. The disadvantage of Pall ring packing tower is that the cost of Pall ring packing is high, it is not suitable for use when the liquid load is small, and the material cannot contain suspended solids, binders and polymers. It is not suitable for complex rectification processes such as intermediate reboilers or multi-side discharges.