Can air purifier HEPA filters be washed and recycled, and what are HEPA filters made of?

air purifierHEPA filterCan it be washed and recycled?HEPA filterWhat's it made of?

Today, many people have air purifiers in their homes, and mid-range air purifier products on the market are currently priced at around 3,000-5,000 yuan, yet the cost of using an air purifier is not just the cost of purchasing the machine. In order to get better indoor air quality, as long as there are people in the house will turn on the air purifier, long time use coupled with the poor air quality of the first-tier cities, the service life of the air purifier filter will also be greatly shortened, and the filter maintenance also requires a small amount of expenditure.

Take an air purifier of about 4,000 yuan as an example, its whole set of filter replacement cost about 800 yuan, has accounted for the entire purchase cost of 20%. so a brand new set of filters can actually use how long? Usually air purifier organ suggested filter replacement cycle for 2 years, but in the haze of the first-tier cities, if you open 8 hours a day, the service life of the filter is usually only half a year. If you do not regularly maintain and replace the filter, not only the purification effect to be discounted, may also cause secondary pollution to the indoor air.

Most air purifiers on the market today use filter adsorption purification method, the advantage is high purification efficiency, large air volume, no ozone release, the disadvantage is the high maintenance cost of the filter material. The general air purifier filter assembly contains a pre-filter, activated carbon filter and the most critical HEPA filter, etc., which is mainly used to filter the larger dust particles in the air, hair, you can look at the material of the pre-filter to choose to wash or vacuum cleaner cleaning. Activated carbon filters are mainly used to adsorb odors and formaldehyde in the air, as long as the regular exposure to the sun, to be volatile formaldehyde can be used again.

HEPA filter is made of fine organic fibers interwoven, through the adsorption of fine particles in the air to achieve air purification, high grade HEPA filter can even be efficient adsorption filtration of particles with a diameter of less than 0.3, to play a role in purifying the air. Many air purifiers HEPA filters are marked with the words "not washable", I believe that many partners are curious why HEPA filters can not be washed, if washed can also be recycled, save out of the replacement of HEPA spending a year less than a thousand dollars.

Next, we found a piece of HEPA filter used for more than half a year, through the real cleaning before and after the purification effect comparison, so that we can see the truth of HEPA filter can not wash.

The truth about HEPA filters not being washable:

A colleague's home air purifier has been used for 2 years, due to the usual high frequency of use, basically half a year will need to replace the filter, today, we invited this air purifier to the truth lab, open the front panel, you can see that the internal filter is basically not maintained, the filter is attached to a layer of dust. Remember that we have previously reviewed this air purifier, the filter is brand new when the purifier outlet position measured PM2.5/PM10 are 0μg/m³, and this one has been used for nearly a year of air purifier filter, measured outlet PM2.5/PM10 were 131 and 234μg/m³, you can see that the filter effect of a single filtration has been significantly attenuated. (Test environment air PM2.5/PM10 about 1300 and 2500μg/m³)

We then put the HEPA filter into the water to scrub, after repeated scrubbing, you can see that the pool has become significantly cloudy, although these particles are difficult to see on the filter with the naked eye, but through the water washing, most of the dust particles have been washed down. After cleaning, dry the filter and put it back into the air purifier.

In the same indoor air environment, measured after cleaning the filter air purifier outlet position PM2.5 / PM10 were 577 and 1222μg/m³, cleaned HEPA filter has almost nothing to purify the effect, and the same gear wind speed under the noise is obviously bigger.

the actual facts

HEPA filter h mesh material is generally polypropylene or other composite materials, belonging to the paper category, water brushing will destroy the filter structure. In addition, the purification principle of HEPA filter is not simply like a sieve to filter out particles larger than the mesh to purify the air. HEPA filter relies on fine particles and filter Van der Waals force between the formation of adsorption effect, water scrubbing also destroys the electrostatic adsorption capacity of the filter, the fine particles can be easily passed through the loss of the ability to adsorption of the filter, air purifiers have become an electric fan. As we have verified, although the surface of the filter after scrubbing looks a lot cleaner, but at the same time also lost the ability to purify, so the HEPA filter really can not be washed, if you feel that the home of the HEPA filter after a long period of time after the use of a dirty, then it is best to be good to change a piece of a new bar, don't worry about the money.

In addition, some HEPA filters made of PET, business publicity can be cleaned, but the PET material HEPA filter purification efficiency is very low, I also caution you not to lose more than you gain, try to replace the high-quality HEPA filter.