In the field of fresh air systems, there are two technologies: electrostatic precipitator or HEPA filter physical filtration. What are the advantages and disadvantages of each technology circuit?
Electrostatic precipitators have always been marketed as "saving consumables" or "no need to replace consumables" to attract consumers, because electrostatic precipitators do not require replacement of the filter screen, but require regular cyclic cleaning of the dust collection device. If in severe haze weather, high-intensity continuous use for 1-2 weeks requires cleaning once, with a high frequency of cleaning. And the dust collection effect will decrease over time of use. If used for a long time, it will cause secondary pollution. To ensure effectiveness, a coarse filter screen should be added to the front end of the electrostatic filter, and activated carbon and a medium filter screen should be added to the back end to absorb carbon powder and ozone. These consumables do not all need to be replaced, and the overall cost will be higher.
In addition, the electrostatic dust collection mode seems to have low actual consumable costs, but it is difficult to maintain and clean. The dust collection devices are all groove structures, and particles are attached to them after high-pressure carbonization, which is stubborn after deposition and requires strong wiping. Sometimes auxiliary cleaning agents are also needed, and it is difficult to brush the inside without a brush.
Generally speaking, electrostatic precipitators are used for industrial purification because electrostatic precipitators have fixed dust collection modules and are costly to produce as small equipment. Additionally, due to their high air volume characteristics, they cannot be fully utilized in smaller spaces, resulting in poor effectiveness. In small spaces, high ozone concentration is more likely to cause harm to human health!
The California government officially banned the sale of air purifiers with ozone depleting function and electrostatic precipitators in 2007, because electrostatic precipitators inevitably produce ozone during operation, which is harmful to human health!
HEPA filter physical filtration technology is a pure physical filtration method that introduces outdoor air into the room through a fresh air system. It adopts a three-level air filtration measure of primary efficiency, medium efficiency (HEPAH11 level), and high efficiency (HEPAH13 level) to thoroughly filter PM2.5 in the air, without producing ozone or secondary pollution. By filtering, fresh air is ensured to enter the room, supplementing the oxygen content in the air and reducing the concentration of carbon dioxide and formaldehyde. Simultaneously expel indoor dirty air, such as bacteria, mold, viruses, odors, etc.
In addition, it can also reduce the energy consumption of air conditioning by exchanging cold and heat between the discharged air and fresh air, which can recover more than 80% of the energy and reduce electricity bills during the air conditioning season by 25%.
With people's increasing attention to the hazards of air pollution, the installation of fresh air systems has become very common. From general residential homes to social places such as primary and secondary schools, kindergartens, and offices, it is necessary to have an understanding of the various technical performance of fresh air systems in order to truly choose a suitable and effective one.
