Types and characteristics of air purifier filters

An air purifier is a device that can purify indoor air. It removes pollutants from the air through various built-in filters, technologies and devices. These pollutants include but are not limited to particulate matter such as dust, pollen, smoke, PM2.5, harmful chemical gases such as formaldehyde and benzene, microorganisms such as bacteria and viruses, and odors. Commonly used filter types and characteristics of air purifiers are as follows:

Primary filter
• Features: Mainly used to filter larger particles in the air, such as dust, hair, fibers, etc. Usually made of non-woven fabric, nylon mesh or metal mesh, the structure is relatively simple and the price is relatively low;
• Advantages: small wind resistance, large dust holding capacity, able to initially block larger pollutants and extend the service life of subsequent filters;
• Disadvantages: low filtration accuracy, limited filtration effect on tiny particles and harmful gases;

HEPA high efficiency filter
• Features: Can effectively filter tiny particles in the air with a diameter of more than 0.3 microns, including pollen, smoke, bacteria, viruses, etc.;
• Advantages: high filtration efficiency, good removal effect on fine particles such as PM2.5;
• Disadvantages: Large wind resistance, requiring regular replacement, relatively high cost;

Activated carbon filter
• Features: Use the adsorption performance of activated carbon to remove odors and harmful gases (such as formaldehyde, benzene, TVOC, etc.) in the air;
• Advantages: Strong adsorption capacity for odors and harmful gases;
• Disadvantages: Limited adsorption capacity, easy to saturate, requires regular replacement or activation;

Photocatalyst filter
• Features: Under the irradiation of ultraviolet rays, it can decompose organic pollutants in the air and has the effect of sterilization and disinfection;
• Advantages: It has a continuous purification effect and can decompose harmful gases;
• Disadvantages: requires ultraviolet light source and relatively harsh usage conditions;

Electrostatic dust collection filter
• Features: Particles in the air are charged through a high-voltage electrostatic field and then adsorbed on the electrode;
• Advantages: low wind resistance, can be cleaned and reused, reducing usage costs;
• Disadvantages: Ozone may be produced, which is potentially harmful to human health;

Composite filter
• Features: Combining a variety of filter materials, such as HEPA filter and activated carbon filter, to achieve the function of removing particulate matter and harmful gases at the same time;
• Advantages: It combines the advantages of various filters to improve the purification effect;
• Disadvantages: The cost is high and the entire replacement is required;

Different types of filters work together in an air purifier to provide a more comprehensive and efficient air purification effect. When choosing an air purifier, you should pay attention to factors such as filter type, quality, and replacement cost based on actual needs and usage environment.