Air Purifier and Electrostatic Technology: Enhancing Air Quality by Capturing Microscopic Particles

Air purifiers have become almost indispensable appliances in modern homes. They can effectively improve the living environment, protecting oneself and family members from the harm of air pollution. Among the threats to health from industrial emissions, vehicle exhaust, and indoor harmful gases, fine particulate matter stands out as a major factor. Electrostatic technology in air purifiers is highly regarded as an efficient method for removing these fine particles, contributing to the overall effectiveness of air purification.

Ⅰ. Threat of Fine Particles to Air Quality

Fine particles are typically defined as solid or liquid particles suspended in the air with a diameter smaller than or equal to 10 micrometers. They are categorized into two main groups: PM2.5 (particles with a diameter smaller than 2.5 micrometers) and PM10 (particles with a diameter smaller than 10 micrometers). Due to their small size, these particles can easily remain suspended in the air and be inhaled into the respiratory system, posing health hazards.

PM2.5 can penetrate deep into the lungs due to its extremely small size, bypassing the respiratory defense mechanisms and causing direct harm to the respiratory system. Prolonged exposure to high concentrations of PM2.5 may lead to chronic respiratory diseases such as Chronic Obstructive Pulmonary Disease (COPD) and asthma. Studies have indicated that exposure to elevated levels of fine particles, especially PM2.5, is associated with increased incidence and mortality rates of cardiovascular diseases, including heart disease and stroke.

Ⅱ. Mechanical Filtration vs. Electrostatic Technology Filtration

Air purifiers, as effective means to improve indoor air quality, employ various filtering technologies and methods to remove fine particles. Among these methods, electrostatic technology is considered an effective approach.

1. Mechanical Filtration

Mechanical filtration is one of the most common filtration methods used in air purifiers. It primarily operates by physically trapping particles in the air, including dust, pollen, bacteria, viruses, and other fine particles. The core component of this filtration method is the filter, with HEPA (High-Efficiency Particulate Air) filter being the most common and effective type.

HEPA filters are highly efficient mechanical filters designed to capture tiny particles in the air. These filters typically consist of a dense network of fibers with gap sizes controlled around 0.3 micrometers. Particles of this size pose the greatest challenge for mechanical filters because they are larger than the fibers of the filter, yet the filter maintains very high efficiency. As air passes through the HEPA filter, the intricate structure of the filter traps and isolates tiny particles in the air, allowing larger air molecules to pass through. This effectively intercepts and isolates harmful particles in the air, thereby improving indoor air quality.

HEPA filters typically achieve an efficiency of 99.97% or higher, specifically for particles of 0.3 micrometers in size. Furthermore, HEPA filters are categorized into different levels, such as HEPA H13, HEPA H14, based on their filtration efficiency and lifespan. While HEPA filters are highly effective, over time, their surfaces accumulate more particles, reducing ventilation effectiveness. Therefore, regularly replacing the filter is a crucial step in maintaining the efficient operation of an air purifier.

2. Electrostatic Technology Filtration

Electrostatic technology is a method that utilizes an electrostatic field to attract and capture tiny particles in the air. Widely applied in the field of air purification, electrostatic technology primarily operates through charged electric fields and electrodes to guide and capture minute particles, thereby achieving the goal of purifying the air.

The first step in electrostatic technology typically involves creating an electric field. This field can be generated by introducing charged materials or using electrodes. Since tiny particles usually carry a certain charge, when these charged particles are placed in the electric field, they experience the force of the electric field and are rapidly attracted to a specific region of the field. Because the purifier contains charged electrodes, which can be positive or negative depending on the charge of the particles, electrodes with opposite charges attract the particles, causing them to deposit on the surface of the electrode.

However, over time, particles will still deposit on the electrodes, accumulating on the surface and affecting the purification effectiveness. To maintain efficient operation, some electrostatic air purifiers incorporate periodic cleaning mechanisms. This involves repeatedly electrifying the electrodes to shake off or collect the particles, or providing an automatic cleaning function, thus achieving efficient air purification with lower energy consumption.

Due to its high efficiency in capturing tiny particles, especially PM2.5 and other fine particles, electrostatic technology is not only applied to indoor air purification but is also widely used in industrial exhaust gas treatment, dust control on electronic production lines, air purification in medical equipment, and other fields. Its ability to efficiently capture small particles makes electrostatic technology beneficial in various environments.

In summary, air purifiers employing electrostatic technology provide an efficient and practical means to adsorb tiny particles, contributing to the improvement of indoor air quality. Despite some inconvenience in maintenance, the characteristics of high-efficiency purification and low energy consumption make electrostatic technology promising in the field of air purification. In the future, with continuous technological innovation, electrostatic technology is expected to further enhance stability, reduce costs, and offer people even healthier and fresher indoor air.