Tips for selecting high flow filter element

How to select high flow filter element? The following is an introduction to you: 1 Selection of filter materials: first, find out the available filter materials according to the chemical name of the fluid to be filtered and the chemical coordination taboo, and then evaluate one by one according to their operating temperature, operating pressure, acid-base value, operating conditions (such as whether to withstand steam, hot water or chemical sterilization, etc.), and remove the unsuitable filter materials The application is also an important consideration, for example, the filter material used in medicine, food or cosmetics must be FDA approved; the ultra pure water must be selected as the filter material which is pure and does not contain the release material which will affect the specific impedance; the filter gas must be selected as the hydrophobic material and whether the "sanitary grade filter" design is required, etc 2 Filter precision; this is a puzzling problem of Zui For example, to remove particles visible to the naked eye, a 25 micron filter should be used; to remove clouds in the liquid, a 1 or 5 micron filter should be used; to filter out bacteria with small Zui, a 0.2 micron filter should be used The problem is that there are two kinds of filtering precision units: Precision / nominal precision Precision / nominal precision means that particles with marked precision can be filtered 100% For any filter, this is almost an impossible and impractical standard, because 100% is an infinite value Generally known filters on the market, such as film, can only be called "approaching" filters strictly, while others are nominal accuracy Nominal accuracy, which is the main problem: "nominal accuracy does not have a common industry recognized and followed standards." That is to say, company a can set the nominal accuracy at 85-95%, while company B would rather set it at 50-70% In other words, company a's 25 micron filtering accuracy may be equal to company B's 5 micron, or finer For this problem, experienced professional filter suppliers will help to choose the filter accuracy, and the fundamental solution is "trial" 3 Design of filter system: this title covers a wide range, such as which pressure source should be selected, how much pressure is required, whether two sets of filters need to be installed in parallel to suit the continuous operation system, how to match the coarse filter and fine filter in the case of wide particle size distribution, whether check valve or other devices need to be installed in the system, etc All of these require the user to work closely with the filter supplier to find out the proper design of Zui 4 Difference between surface filtration and deep filtration: surface filtration mainly adopts screen material, while deep filtration adopts felt material Their differences are as follows: 1) screen material (nylon monofilament and metal monofilament) directly traps impurities in filtration on the surface of material The advantages are that the monofilament structure can be cleaned repeatedly, and the consumption cost is low; the disadvantages are that the surface filtering mode is easy to cause the surface of the filter bag to be blocked This type of product Zui is suitable for the coarse filtering occasions with low precision, and the filtering precision is 25-1200 μ M
2) felt material (needled cloth, melt blown non-woven cloth) is a common deep three-dimensional filter material, which is characterized by loose fiber structure, high void ratio increases the volume of impurities, this kind of fiber material belongs to the multiple interception mode, that is, the larger particle impurities are trapped on the fiber surface, while the fine particles are trapped in the deep layer of the filter material, so the filter has a higher filtering efficiency, In addition, the high-temperature surface heat treatment, namely the application of instantaneous sintering technology, can effectively prevent the fiber from being lost due to the high-speed impact of the fluid during filtration; the felt material is disposable (disposable), and the filtration accuracy is 1-200 μ M 5 The main materials and properties of filter felt are as follows: Polyester - filter material fiber commonly used by Zui, with good chemical resistance and working temperature less than 170-190 ℃ polypropylene - used for liquid filtration in chemical industry, with some acid and alkali resistance functions and working temperature less than 100-110 ℃ wool - good solvent resistance function, but not suitable for acid and alkali resistance filtration Nilindron -- good anti chemical function (except anti acid), working temperature less than 170-190 ℃ fluoride -- excellent anti temperature and anti chemical function of Zui, working temperature less than 250-270 ℃