How many kinds of filter materials are available for HEPA filters?

03/08/2020

Those who are familiar with filters know that air filters are divided into primary, medium, and high-efficiency levels according to their filtration efficiency, and the filter materials corresponding to different levels of filters are also the same. Today, I would like to introduce to you what kinds of filter materials are available for high-efficiency filters?

At present, there are mainly three kinds of filter materials found in the market that can achieve high-efficiency filtration, namely PP filter media, glass fiber filter paper, and PTFE. The following is the same for everyone.

PP filter material

PP filter material, also known as ultra-fine polypropylene fiber, is a new type of filter material made of polypropylene special resin through melt-blown non-woven. The filtration efficiency is 99.9% to 99.999%, and the filter particle size is 0.5. Above micron, it is characterized by the low cathode and high efficiency (also known as chemical fiber material). Its characteristic is that the filtration efficiency can reach F8-F9, and its discount number can only be discounted up to 90%.

Glass fiber filter paper

Glass fiber filter paper is also called glass fiber filter paper. Glass fiber material is the most commonly used material for HEPA filters with and without partitions. The filtration efficiency is 99.9% to 99.999%, and the filter particle size is 0.3 microns or more. Its biggest weakness is that it contains up to 10.7% boron (B2O3), and it is easy to generate silicon tetrafluoride when reacting with hydrofluoric acid, which will break the filter material and form secondary pollution.

Glass fiber: The main component is SiO2,

Characteristics: Glass fiber is an inorganic fiber. It is made by melting glass frit at a temperature of 1300-1600°C, drawing it from the molten state, and quickly quenching it. The density is 2.64g/㎡. The glass fiber is chemically resistant In terms of corrosion, in addition to hydrofluoric acid, high temperature, and strong alkali, it is relatively stable to other media. The disadvantage of glass fiber is poor folding resistance.

In the purchase, it is generally calculated by kg. If the measurement is square meter, it can be calculated as 75 grams per square meter. In the price, no partition is slightly more expensive than the glass fiber filter paper with partition.

PTFE

Using PTFE as raw material, through a special process, two-way stretching, using the unique node fibril property of PTFE film, smooth surface, chemical resistance, breathable and impermeable, large air permeability, flame retardant, high-temperature resistance, strong acid-resistance Alkali, non-toxic and other characteristics, the product made has high filtration efficiency, up to 99.99%, close to zero-emission; low running resistance, fast filtration speed; long service life, reusable, thereby reducing operating costs. Mainly used for flue gas filtration of various industrial furnaces such as chemical industry, steel, metallurgy, carbon black, power generation, cement, garbage incineration, etc.

Features

1. Surface filtration, low filtration resistance, easy to peel off the dust layer, solving the problems that cannot be solved by conventional filtration.

2. The aperture is controlled between 0.2~3μm, which can effectively trap dust. PTFE filter membrane

3. The PTFE filter membrane has a smooth surface, no condensation, easy to clean dust, maintain the dust removal efficiency, and greatly enhances the service life.

4. The filter material has a long service life, high and low-temperature resistance, chemical stability, and non-aging properties, which make it extremely adaptable to temperature, humidity, and corrosive gases, which is unmatched by conventional filter materials.