Brief description of the application of testing methods for high efficiency activated carbon equipme
Brief description of the application of testing methods for high efficiency activated carbon equipmentSeveral issues need to be taken into account when testing this equipment.Usually, a special filter testing apparatus can be used, and the fan duct system and the flow rate of the equipment are tested by this technology, but the testing of the efficiency of the equipment usually requires the solution of two problems: the stability of the artificial aerosols and the accurate detection of very low concentrations after filtration. I. Problems with aerosols As the filter media used in high-efficiency filtration equipment are relatively fragile, various countries currently require 100% unit-by-unit testing of these products, and this testing must be non-destructive, which means that the aerosols used must not have an obvious destructive effect on the filter. As the object of high-efficiency equipment filtration are sub-micron pollution particles when testing we need to use easy-to-penetrate tiny particles, to make the test results more practical and significant, and the following four effects are currently recognized filtration mechanisms. 1. Inertial collision; 2. Direct retention; 3. Gravitational sedimentation; 4. Diffusion effect. In addition to this, there are also van der Waals forces, i.e. surface adsorption, molecular gravity, and electrostatic forces, which do not play a major role in filters without charged fibers and are therefore not analyzed in detail. Over the past few years, with the continuous development of the filter materials we use and the detection technology, it is now generally accepted that O.1 - 0.15 pm is the particle size that is easy to penetrate, but here we need to note that this is not the same mechanism as sieving through a sieve, and it does not mean that the smaller the diameter of the particle the easier it is to penetrate. II. The problem of concentration detection As the concentration of particles after filtration is very low in high-efficiency filtration equipment, it is difficult to measure the concentration using the "sampling-weighing" method, so the use of light scattering, flame photometry, and particle counting methods are more common. |