Nowadays, more and more families are installing water purifiers. Many people often ask: Why do water purifiers produce more waste water? Drained it, it feels wasteful. Is the "waste water" water purifier really useless? So let's popularize the relevant knowledge of water purifier wastewater.
The core technology of this kind of water purifier that produces wastewater is called reverse osmosis membrane. This kind of water purifier is the most common water purifier on the market, and it is also the water purifier product with the highest filtration accuracy among the current household water purifiers.
So, why does the water purifier produce waste water?
How reverse osmosis works ?
The reverse osmosis membrane is a high-precision filter element (precision 0.0001 micron) in the pure water machine. It uses a molecular-level filtration method to remove harmful substances in the water and produce pure water.
The main filtration of reverse osmosis water purifier is divided into five steps, but the number of filters is different:
1, PP cotton filter
The first filter is generally PP cotton, which can remove the larger particles of impurities in the water, such as debris, rust, etc. This is also to protect the reverse osmosis membrane and prevent it from being blocked by debris. However, some relatively small bacteria and viruses , Heavy metals, etc., cannot be removed at this link.
2, initial filtration (activated carbon)
The initial filtration generally uses granular activated carbon and compressed activated carbon, because the granular carbon has a developed pore structure and strong adsorption capacity, which can remove residual chlorine and corrosive substances in the water. In this step, the heterochromatic and odor in the water can be removed.
3, reverse osmosis membrane filtration
Bacteria, viruses and other harmful particles that cannot be removed in the initial filtration process will be filtered out after passing through the reverse osmosis membrane. The filtration accuracy of the reverse osmosis membrane is very high, only 0.0001 microns, and the smallest virus is also 0.02 microns, so that almost all impurities in the water can be filtered out through the reverse osmosis membrane. The water that passes through the reverse osmosis membrane is pressurized, and there is always a part of the water mixed with impurities that cannot pass through the reverse osmosis membrane, so this part of water is also called concentrated water, which is what we often call wastewater.
4, the fourth stage
Finally, it is usually post-activated carbon filtration to further absorb the different colors and odors in the water, improve the taste of the water, and obtain water that we can drink directly.
5. The fifth stage
The fifth stage and the final further water quality optimization, generally weak alkaline filter and UV ultraviolet sterilization. Because the water filtered by the RO membrane is pure water and does not contain any minerals, through the fifth stage of the weakly alkaline filter element, macro and trace elements that are beneficial to human health can be added to the water. The UV germicidal lamp can further kill the germs that grow in the water.
RO machine is based on the principle of quality water supply, and there is no waste water
From a professional point of view, there is no waste water in the reverse osmosis water purifiers on the market. It has only one inlet water (or "raw water") and two outlet waters, namely "permeate water" (i.e. purified water, drinking water). Water) and "concentrated water" (i.e. purified water, washing water). In other words, the reverse osmosis water purifier is a good quality water supply system.
Tap water is filtered by PP cotton filter element, activated carbon adsorption filtration, compressed activated carbon filtration and other three pretreatments (removal of residual chlorine in the water, most of the suspended matter, rust, colloid, and some organic matter, smell and taste), a small part of the water After reverse osmosis (remove all kinds of impurities in the water, including bacteria and other microorganisms, to make "permeate water") and post-positioned granular activated carbon adsorption filtration (further remove organic matter, smell and taste, and improve taste) to make pure drinking water For drinking.
The "waste water" is also filtered through the first three stages of filter elements, and a large part of the impurities have been removed. In addition to the salt content and bacteria in the tail water is slightly higher than that of tap water, most of the other indicators, such as turbidity, color, organic matter, colloids, etc., are lower than tap water. Such water is by no means waste water. However, most of the water (concentrated water) has gone through the first three stages and failed to undergo the post-secondary treatment, and becomes purified water and flows out as washing water.
The so-called wastewater is actually better than tap water
In the daily life of the family, the demand for washing water is much larger than drinking water, such as washing pots, washing dishes, mopping tables, washing clothes, mopping the floor, flushing toilets, etc., which are all very good.
The concentrated water of reverse osmosis water purifiers on the market has undergone three filtration treatments. Therefore, in addition to the higher salt content than tap water, most of the other indicators, such as turbidity, chroma, residual chlorine, smell and taste, organic matter, and suspension Turbidity, colloids, COD (chemical oxygen demand), TOC (total organic carbon), SDI (pollution index), etc., are all much better than tap water! How can such good water be called "wastewater"?
