Buying an air purifier is often seen HEPA in the end what is it?
HEPA filter is a dry high-efficiency air filter that can be handled, and there are a variety of materials that make up HEPA, which can be divided into PP (polypropylene) high-efficiency filter paper, PET filter paper, PP and PET composite high-efficiency filter paper, and glass fiber high-efficiency filter paper. Among them, PP (polypropylene) is paper, so it is generally not washable. The other part of the HEPA filters are made of PET or PTFE, which is where a lot of the claims of washable HEPA filters online come from, although PET is very inefficient.
What are its features?
HEPA is mainly used to capture particles of dust and various suspended matter below 0.5um. The use of ultra-fine glass fiber paper as a filter material, offset paper, aluminum film and other materials for the split plate, and wood frame aluminum alloy glued together, using special silicone rubber for, no smell, the surface will not be hardened, long time there will be no cracks, stable chemical properties, corrosion resistance, can absorb thermal expansion and contraction of the stress generated by the stress will not be cracked, the softness and hardness of the moderate, elasticity and recovery of good.
Its advantages?
1. Filter single purification efficiency.
2. Purification rate decreases slowly with air volume and usage time.
3. High-efficiency HEPA filters can achieve interception of major viruses.
Its filtration mechanism?
Includes four.
1. The first is the interception mechanism, which works on large particles.
2. The second mechanism is the effect of gravity, the volume of small dense particles, in the HEPA filter when the movement speed will be reduced, the natural settlement to the HEPA, the process is somewhat similar to the sediment in the water downstream of the river settlement process.
3. The third mechanism of the HEPA filter is the influence of airflow. Due to the uneven weave of the HEPA filter, the formation of a large number of air vortex, ultra-small particles by the influence of this cyclone adsorption in the HEPA filter to achieve the purpose of filtration.
4. The fourth filtration mechanism for ultra-fine particles in the Brownian motion under the action of the impact to the HEPA filter fibers by the Van der Waals force, be filtered.