Is there a filter or a filter?

Severe air pollution has led to rapid development of the air-net industry. The diversified products in the market make it difficult for consumers to choose. According to the survey, 60% of users indicated that the lower the cost, the better. Which filter and filterless purifier can have better purification effect? From the technical level, it is difficult for consumers to understand who is good or who is bad. This is also the reason for the inferior purifier. But the key is whether the purifier products meet their respective normative standards under the two principles. This must be clarified before purchasing.

Electrostatic air net working principle

Compared with the traditional filter air purifier, the most obvious difference of the electrostatic air purifier is probably the "no filter" feature. However, without a strainer, why does it purify the air?

The product is attached to the tungsten wire by high voltage to generate a corona, which releases a large amount of positive charge. The positive charge collides with the pollutants in the air to make it positively charged, and the product's dust collecting plate is negatively charged with positive charge pollution. When the object encounters a negatively-charged dust collecting plate, the positive and negative particles are absorbed, and the pollutants are adsorbed on the dust collecting plate to release fresh air. With this principle, electrostatic air purifiers do not require a strainer.

Compared with traditional purifiers, the main requirement of electrostatic purifiers is their dust collection capacity and ozone emissions. Since the dust is removed by the corona field generated by the high pressure, there is a requirement for high pressure. Theoretically speaking, the higher the high pressure, the better the dust collecting effect, but the more ozone emissions. Therefore, the domestically unqualified purifiers have poor dust collection capacity or excessive ozone. The harm of excessive ozone to the human body is also not to be underestimated.

Compared with the traditional purifier, the electrostatic purifier needs regular time and effort to remove and wash, and some of the purifier filter water is easy to hang, which is a paradox!

Filter type empty net working principle

The filter-type empty net belongs to the passive purification. The air is pumped into the machine by a fan, and the air is filtered through the filter screen of the inner raft, which can mainly filter dust, odor, toxic gas and kill some bacteria. The filter is divided into: dust collection filter, formaldehyde removal filter, deodorization filter, HEPA filter, etc. The higher cost is the HEPA filter, which can decompose toxic gases and sterilize, especially to suppress secondary pollution. The disadvantage is that there is a late cost.

When dust encounters HEPA filter

This is a cross-sectional view of the HEPA filter on Wikipedia. When dust passes through the filter, three things happen. Impact interception, curve interception, diffusion

Interception, that is, the dust is larger than the pores of the filter and is directly blocked; the interception is the process in which the dust is absorbed by the airflow in the overpass of the filter and finally hits the filter fiber; the adsorption is due to the static electret of the filter. Electrostatic adsorption is adsorbed onto the filter screen and absorbed.

When we look at the HEPA filter in a microscope, we find that the HEPA filter is a mesh of very high-density fibers that are interwoven and imperfect. There are generally two types of screens used in air filtration technology. The first type uses PP spray melting as a constituent material of the fiber, and is subjected to electrostatic electret treatment to form a sieve; the second filter uses glass fiber as a filter. Material, no static electricity, but the fiber structure is very dense, completely relying on very small fiber gaps to block dust. The first filter is often used in household purifiers, and the second filter is used in industrial clean rooms, chip shops, operating rooms, high-end purifiers and high-end fresh air systems.

It sounds like the glass fiber filter seems to have many advantages. Why is the glass fiber filter not becoming mainstream? In fact, the cost of the glass fiber filter is much lower than that of the PP HEPA filter, and the reliability is higher than PP. Filter, but it has very fatal drawbacks:

1, the wind resistance is too large, the need for a very strong motor to promote 2, high wind resistance, high-power motor caused by noise 3, in order to reduce wind resistance must make the filter volume is very large, so the volume problem is not easy to solve.

2. For home use, power consumption and noise are fatal. Therefore, scientists have invented the electrostatic spray technology on the basis of PP spray melting, so that the filter is electrostatically charged. After using the electrostatic electret technology, even the PP spray-melting filter with smaller wind resistance and larger fiber gap is also used. Very fine particles (such as 0.3 microns, 0.1 microns) can be treated by electrostatic adsorption. So what are the disadvantages of electrostatic electret technology? Electrostatic electret, no matter how superb the technology, there is a time of failure. After the static electricity loses effect, the adsorption capacity of small particles decreases rapidly. Therefore, we need to periodically change the filter according to the manufacturer's instructions.

3. The dust holding capacity represents how much dust a filter can hold, which is often influenced by the pore size of the filter paper fiber and the electrostatic electret technology. In general, H11 is the bottom line for household use, and H13 has already had a relatively large dust holding capacity. However, it is necessary to pay attention to the high dust-proof filter screen, the wind resistance will be greater, although some high-grade, low-priced H13 filter is very attractive, but pay attention to the noise problem.

Derivatives of air purifiers

The car air purifier is a derivative of the air purifier. The principle of action is the same. In the North China region, our primary consideration is the effect. The electrostatic car purifier has a slow purification effect and may also generate ozone. In the relatively small space of the car, it actually occurs. Another kind of health hazard, the cleaning of the collection net is not convenient.

The filter-type on-board purifier can better absorb harmful substances, and the purification effect is efficient and fast, and the replacement of the filter screen is convenient and quick. Lixing intelligent car dehumidifier can effectively remove harmful substances such as PM2.5 and TVOC.

Some common problems with HEPA filters

If my machine standard uses H11 filter, can I replace the third-party H13 filter? It is not recommended because it will affect the air volume and air circulation capacity of the machine, but reduce the purification efficiency of the machine. It is recommended to increase the filter replacement. The number of times is resolved. Similarly, the H13 machine is not recommended to replace the H11 filter because the increase in wind speed will further reduce the filter adsorption performance.

Is the single filtration performance of the filter paper important? A specific analysis is required . Important for harsh environments and new wind turbines, but with a reduced level of importance for internal circulation purifiers. The filter level should be considered before considering the CADR of the machine.

Is it important to seal the filter to the machine? This is important if you want to extract the air outlet data, but from a practical point of view, depending on your personal preference. If the seal is not tight, some dusty air will not pass through the filter directly through the inside of the machine, which will cause dust inside the machine. Therefore, it is recommended that users of HEPA purifiers should periodically disassemble the machine to clean the inside of the machine to prevent secondary pollution.

The smaller the filter, the smaller the wind resistance? The answer is the opposite. The larger filter has a larger expansion area. If the small filter has ten holes, the large filter has twenty holes, so the wind resistance is smaller. This is the thicker the wire, the smaller the resistance is. So don't exclude large filters.

Some HEPA filters advertise that they can be antibacterial. Is this true? The treated filter will have some antibacterial ability, but the effect is limited. Don't hope for this. In addition, an important way to keep the filter from becoming a hotbed is to keep it turned on all the year round.anti spy screen protector, privacy phone screen film, Privacy Screen Protector, Samsung privacy screen.anti spy screen protector, privacy phone screen film, Privacy Screen Protector, Samsung privacy screen