For the filtration performance level of the air filter material, the filtering efficiency or (transmittance), filter resistance (pressure drop), a dust removal amount (natturity ratio), quality factor, etc. are evaluated. Among them, filtration efficiency refers to a ratio of the concentration of upstream particulate matter concentration to the upstream particulate concentration value of the upstream particle concentration value by the upper reaches of the upper and downstream particulate matter concentration values ​​by the upper and downstream particulate concentration values ​​of the upstream particulate concentration value of the upper and downstream particles. The filtration efficiency directly reflects the removal effect of the material to the particulate matter in the gas, not only important indicators of filter filtration performance, but also important parameters for measuring the air filter filter.

In standard EN779: 2012 “General Ventilation Filter Filter Performance Determination”, filtering efficiency can be divided into coarse effect, alive, GAO effect, grade, such as a coarse filter, such as a coarse filter, such as a coarse, gaO effect, in accordance with the size and filtration efficiency of filter particles and filtering efficiency. (G1 ~ G4) Mainly for 5.0 μm or more, according to the efficiency of filtration (20.00000 to 90.00000); the protein-only filter (F5 ~ F9) is 40 to 5.0 μm of the filtration efficiency of 40.00000 ~ 95.00000 (color color Method); GAO Eye HEPA filter (H10 ~ H14) mainly arrested 0.5 μm or less particulate matter.

空气过滤器的等级划分以及部分纤维的应用

Classification of air filters and the application of several fibers

The filter performance level of the air filter material is usually evaluated by filtering efficiency or light transmission (light transmittance), filter resistance (pressure drop), dust (pollution acceptance rate), quality factor, etc., filtering efficiency refers to a certain test. Under conditions (filtered wind speed, particle size, particle concentration, etc.), the difference between the concentration of the upstream particles of the fiber filter and the concentration of the downstream particles. The filtration efficiency directly reflects the removal effect of the filter material to the particulate matter in the gas. It is not only an important indicator of filter material filtering performance, but also important parameters for measuring the air filter filter.

空气过滤器的等级划分以及部分纤维的应用

In EN779: 2012 “General Ventilation Filter Filter Performance Determination”, according to different filter particle size and filtering efficiency, filtering efficiency can be generally divided into three different levels: coarse efficiency, medium efficiency and GAO efficiency. For example, the coarse-efficient filter (G1 ~ G4) is mainly used for Mμ, and the above 5.0 particles removed by filtration efficiency (20.00000 ~ 90.00000); 1.0 ~ 5.0 μm germal filter (F5 ~ F9), particle filtering efficiency 40.00000 ~ 95.00000 ( Coloring method); the GAO effect filter (H10 ~ H14) mainly captures particles of 0.5 μm or less.

Application of fiber filter material in air purifier

Fiber filter materials are usually used in indoor air purification. The fibers used in these materials are mainly synthetic fibers, such as polypropylene (PP) fibers, polyester (PET) fibers, and homopolymer polypropylene (PAN) fibers, mainly non-woven fabric. The coarse air filter is mainly made of glass fiber, PP, PET, wire mesh, etc. According to research, the high filtration efficiency of some GAO effect fiber filtration can reach 99.99999.

In general, the GAO effect fiber filter material mainly includes a micro-tank fiber filter and a block fiber filter.

Glass fibers are commonly used in air filtration materials, mainly divided into short-cut glass fibers and glass wool. The glass fiber is melted about a glass ball at around 1500 ° C and then processed into a fibrous material by a high pressure melt spray or wire. The fiber diameter obtained by stretching is relatively uniform. The so-called short-cut glass fibers are cut according to the required length. The fiber diameter obtained by the meltblown method is small, and the cotton glass fibers are formed, commonly referred to as a glass wool, and the fiber diameter and length have a certain distribution.

The main components of the glass fibers include SiO2, Al2O3, Ca0, MgO, Na20, etc., wherein SiO2 takes 53 to 70. These oxides exhibit different pH in water. SiO2 represents a weak acid component, and CAO represents a strong alkali component. Therefore, the glass fiber surface will have a weaker acid point and low concentration of strong base. These oxides easily enable the surface of the fiber to carry opposite charges in water, resulting in mutual attraction and flocculation between the fibers. Whether the glass fibers can be evenly dispersed in the dispersion medium, thereby promoting good intersection between the fibers, is an important factor affecting the filtering properties of the glass fiber air filter paper. By reducing the pH of the slurry, adding a surfactant, increasing the viscosity, can improve the dispersibility of the glass fiber in water.

By wet paper, the corresponding chemical reagent is added to uniformly disperse the glass fibers in water to form a suspension, and then water is filtered on the molded web to form a glass fiber paper. The glass fiber is small, high filtering accuracy; at the same time, the glass fiber modulus is high, relatively hard, so that the fibers are small, but it is not easy to collect, and the volume density is relatively low, so the filter resistance is also low. The performance of GAO effect is the main reason for the main position of fiberglass filter paper in the market.