Look at the filter element first: it is the core component of any water purifier, and the quality of the filter element directly affects the purification index of the water purifier, which is undeniable.
First of all-let's pay attention to whether the filter element can filter impurities and make the water look clearer (it can be said that any water purifier can do it, but different filtering methods have completely different effects). Generally speaking, it can be divided into two categories, and the name is beautiful.
Filter membrane: the market is also full of various well-known filter membranes, pp cotton and so on; In fact, there is only one function, filtering impurities above a certain specification.
Reverse osmosis: the most common in the market, and the filtration rate of 99% has become its biggest selling point;
Disadvantages are also obvious, too clean (it is not recommended for adults to drink for a long time, there are no minerals beneficial to the human body, and infants and the elderly are prohibited; And cannot filter microorganisms such as bacteria and viruses).
By the way, popular science: the application scope of reverse osmosis-the preparation of space water, purified water and distilled water; Water for alcohol production and alcohol reduction; Preparation of water for pharmaceutical, electronic and other industries; Concentration, separation, purification and water production of chemical processes; Boiler make-up water softened water; Desalination of seawater and brackish water; Water and wastewater treatment in papermaking, electroplating, printing and dyeing, food and other industries; Advanced treatment of urban sewage.
Secondly, we should pay attention to whether the filter element can filter odor and improve the taste (any water purifier with activated carbon can do it, but the structure of the filter element leads to great differences in effect, life and price).
Granular activated carbon filter element: odor can be removed in a short time, but after a long time, it will be washed out of the waterway by water and lose the filtering effect; The disadvantage is that the service life is uncertain (users will not know until they find that the filter element has lost its purification ability)
High density activated carbon: long service life; Block structure, will not form a waterway; The disadvantage is that it is complicated to make and expensive (100 times higher than granular activated carbon with the same weight) because of patent protection (leading to high production cost).
In recent years, a kind of diatom mud filter has also appeared: popular science: diatom mud (English: diatom mud). The main raw material is diatom mineral-diatom, which was formed hundreds of millions of years ago. Diatoms are natural substances deposited by algae living in oceans and lakes. Its main component is opal, which is rich in many beneficial minerals and has a light and soft texture. Electron microscope shows that there are countless tiny holes on the surface of its particles, with a porosity of over 90% and a specific surface area. Diatom mud products have a unique "molecular sieve" structure, which has a strong role in purifying air and eliminating odor. Therefore, it can be regarded as having dual functions of filtering impurities and odors at the same time, but it can't filter bacteria (most bacteria and fungi are smaller than 0.2 micron in size and can't be directly filtered, and algae itself will also carry bacteria. )
Another ceramic filter element: the manufacturer claims that it can filter, resist bacteria and activate. At present, the ceramic filter element with the highest filtration accuracy in the world is a double-control membrane ceramic filter element with an average pore size of 0. 1μm (micron).
but
At present, the smallest known bacteria are nanobacteria, whose cell diameter is only 50nm=0.05 micron, even smaller than the largest virus.
Most viruses have a diameter of100 nm (20-200 nm), the larger viruses have a diameter of 300-450 nm, and the smaller viruses have a diameter of only 18-22 nm.
Whether it can achieve antibacterial effect can be imagined.
Finally-pay attention to whether the water purifier can kill microorganisms. Viruses and bacteria in microorganisms are potential pathogens and must be removed (general products can't kill microorganisms; Some products can kill microorganisms, but technology determines the risk of purification)
Physical antibacterial: it is to physically block the passage of bacteria and viruses, and the diameter of viruses and bacteria is not difficult for everyone to choose.
Chemical antibacterial: use chemical filter to kill microorganisms; Disadvantages: chemical residue, affecting taste and health (treatment: after installing chemical filter, improve the taste of ion filter or activated carbon filter; So that consumers can't directly detect the abnormality from the taste, which improves the difficulty of identifying chemical residues)
Ultraviolet sterilization; The sterilization rate is as high as 99%; Disadvantages: need to be charged (potential leakage safety hazard; Of course, the wireless transmission technology of electric energy can avoid potential risks), but this technology is protected by patent (high production cost)
A qualified water purifier can be sold in China after filtering impurities, retaining minerals beneficial to human body and improving the taste of drinking water (reaching the standard of China).
A high-quality water purifier must: filter impurities, retain minerals beneficial to human body, filter various chemical pollutants, improve the taste of drinking water, and kill bacteria and viruses at the same time (in line with international standards, it can be tested and sold in any country and region in the world).
In China, the traditional tap water production technology has a history of 100 years. At present, most water plants are still based on "flocculation-sedimentation-filtration-chlorine disinfection". The national standard for drinking water in China is based on the national standard GB 5749—2006 of People's Republic of China (PRC). This standard has been used for 10 years, while developed countries generally revise the standard every 3-5 years.
You may think it is a little long, but I am forced to explain all kinds of products on the market! But everyone should be happy. Congratulations, you have read the longest part of this article.
Second, look at the installation: whether the installation of the water purifier is convenient directly affects your future use (is it convenient to move? Can I install it myself? The simpler the installation, the more convenient the maintenance)
First of all, avoid-changing pipes. The so-called off-stage machine will feel very inconvenient when the filter element needs to be replaced.
(For example, reverse osmosis needs to install a booster valve, and the pipeline must be replaced, so it requires professionals to install it at home, which is very troublesome and has potential safety hazards for personnel to enter and leave)
(For example, for low-end machines, it is also necessary to replace the pipes and install additional purified water outlet pipes, and it is also necessary for professionals to install them at home. )
Of course, it is not absolute. Now businesses are trying to avoid changing pipelines, and they need to ask in detail when purchasing.
Of course, it is best-there is no need to change pipes. Wall-mounted or table-top water purification equipment generally belongs to this category, and it is very convenient to install and replace.
(For example, Yizhiyuan water purifier uses a diverter valve, which can separate clean water from tap water only by connecting the diverter valve to the faucet. The installation is very convenient, and users can easily assemble and debug it themselves. )
Third, look at consumption: First, wastewater-the water purifier of reverse osmosis technology will produce wastewater in the process of purifying water.
Heavy metal elements in wastewater often exceed the standard by several times or ten times, so washing clothes with discharged wastewater will harden clothes; Used to mop the floor, the floor tiles are damaged; Even flushing the toilet is not allowed, which will corrode ceramics; Washing vegetables is even more impossible; Therefore, the production of waste water greatly increases the use cost.
The proportion of wastewater is also a key indicator that directly affects the consumption of water purifiers. The ratio of waste water produced by low-end water purifiers is as high as 1:6 (purifying 1 ton of drinking water requires 6 tons of water; 3 yuan 1 ton tap water, then it costs you 2 1 ton direct drinking water.
Some mature enterprises can reduce the waste water consumption to 1:3 (that is, drinking 1 ton of direct drinking water needs 12 yuan).
As time goes on, this is an unknown cost (the heavier the water pollution, the higher the proportion of wastewater)
For water purifiers that do not adopt extreme technologies such as reverse osmosis, wastewater will not be generated in the process of water purification, and the purification cost can be appropriately saved.
Secondly, the filter element-any water purification equipment will filter impurities and other harmful substances to pollute the filter element during purification, so it is necessary to replace the filter element regularly.
Water purifiers with several common filtration technologies in the market: generally, the impurity filter element, pp cotton and activated carbon filter element are replaced every 3 months; Replace the reverse osmosis filter element in 6 months; Price150-800 yuan. If the filter element is replaced on time within one year, it will cost about 100 yuan *3 filter elements *4 times +800 yuan *2 times = 2,800 yuan; In fact, the cost of the filter is far more than that, but many people didn't replace it on time because they didn't know when to replace it.
High-end water purifiers only use the filter element once a year (the filter element is integrated), and the cost is about 1500.
Convenience: Whether the water purifier is convenient in use is also an important indicator to determine the quality of a water purifier.
Is it convenient to replace the filter element?
Some inferior or low-end water purifiers boast that they don't need to replace the filter element in order to make people feel convenient and save trouble. Then how do they explain: "What about the impurities that are filtered out?"
So they actually made it up and said: magnetization?
Magnetization: refers to the process of obtaining magnetism from substances that are not magnetic.
Instead of what some salespeople say: consciousness is melted by magnetism!
The so-called magnetized water is that ordinary water passes through a magnetic field with a certain intensity at a certain speed along the direction perpendicular to the magnetic field lines, so that ordinary water will become magnetized water.
They boast that they can purify this. Where is the improvement?
However, magnetized water can completely lose its magnetic force only by leaving the magnetizing equipment for 30 seconds, and the effect can be imagined.
The most reasonable statement is backwashing: not long ago, I heard some salespeople say that the filter element of a brand water purifier does not need to be replaced. As for cleaning once every 7 days, it can be used for 20 years (once every 7 days, 4 times a month, 48 times a year! It needs to be cleaned 960 times in 20 years)
It is also a miracle to persist (so, how much can it cost to clean each time) (if you forget to clean the clean water you drink? ) I admire them for playing so well! ! Of course, this is a joke. Their so-called cleaning: in fact, it is to wash the equipment with water and clean up the filtered impurities. Three minutes or five minutes at a time? I don't remember exactly. This is an unknown cost, but there are also huge risks.
Why?
Have you ever waited for a red light? 99 seconds is 1 minute 30 seconds, and people will be impatient and unable to stay. Maybe you will do something else. What will happen if you forget to turn off the tap? Light waste, heavy flooding. Do you think so?
As far as filter element replacement is concerned, it is often very complicated to replace the filter element of water purification equipment on the market (if it is a set of 5-level purification equipment, replace the filter element once every 3 or 6 months, with 5 filters at a time; 3 filter *4 quarters +2 filter *2 half a year = 14 times; Once a month on average), but for the average family, it needs professional on-site installation (14 on-site service, which may result in 14 service charge and 14 burglary risk).
Discharging waste water gives people the illusion that the filter element is clean, which is also a common sales method for merchants. Why is it illusion? First of all, this method can only be used on the filter screen, but it will increase the consumption of activated carbon filter (activated carbon filter: the maximum service life of granular filter is 6 months, 1 year is only a few tons of water, so it must be replaced). In fact, such constant backwashing of the filter will also consume the life of the filter.
Therefore, some high-end water purifier manufacturers use filter elements, which can be easily replaced by themselves, which is convenient and time-saving.
Personally, I suggest that you'd better buy a product that replaces the filter, but now there is on-time door-to-door service, and it is difficult to find high-quality merchants, and many merchants do not provide on-site service for free. You can choose a water purifier to replace the filter element, and you can buy it yourself when replacing it. Just take the filter out and replace it with a new one. Personally, I think this kind is the safest. I can change it myself, and I don't need to find someone else to visit.
Finally, the prompt function-when to replace the filter element is also one of the advantages of high-end products.
Low-end products will not prompt the service life of the filter element, and it depends on the user's own estimation or replacement according to the instructions (in this way, even if the filter element fails, it will not meet the purification requirements or even become waste water, and the user will not know to drink it as usual; How terrible! Heavy metals and pollutants accumulated for several months were inadvertently drunk by you)
High-end products provide template indicator light to remind users whether the filter element needs to be replaced.
Another point is convenience-different technologies will bring different experiences when used (for example, some products need to be turned on, turned off when power is off, and must be restarted when talking. Maybe it's been a long time, the customer can't find the manual, and forgot which button to restart? ! This will not happen to high-end products, and incoming calls can be used normally without restarting. Is it more convenient)
Fifth, look at word of mouth: through the above understanding, you should have a clear understanding of the purchase of water purifiers. Therefore, any water purifier that says that there is no need to replace the filter element is fooling you. If you don't believe me, let him read the instruction manual, which will definitely indicate the replacement time of the filter element. For an untrustworthy company, the product quality will not be so good! !
Sixth, look at technology: the technology here refers to world-class patents (not everyone in the market can use them, but everyone is using them)
Protection period of patented technology: 20 years for invention patents, and 10 year for utility model patents and designs from the date of application. During the period, others have no right to use it. If the protection expires, they can apply to the patent applicant or unit for authorization and pay the fee (it will be the technology used by everyone in about 30 years, and it will be free at this time). So the technology that everyone is using in the market can be regarded as outdated technology. !
Seventh, look at the sales volume: a good salesperson will introduce the water purifier he sells in detail, as well as the comparison with other similar products, as well as the performance of various devices, instead of blindly advocating his own products.
By the way, this is also a way for many water purifier salesmen to mislead consumers (drinking alkaline water is more beneficial to health! ! )
In fact, drinking alkaline water is the same as drinking acidic water.
Because normal human body fluids are weakly alkaline, the pH value is around 7.4. In daily life, human body fluids have a strong neutralizing and buffering function, and people can maintain the balance of pH, so no matter whether the food you eat is acidic or alkaline, the pH of the human body remains basically unchanged, and there is no so-called "acidic constitution" caused by using acidic foods. Therefore, when water is drunk into the stomach, the environment of the stomach itself is acidic, and the pH value is 2-3. Gastric juice is a very acidic buffer solution. No matter what water you drink, the pH value will become acidic when you drink it in your stomach.
Therefore, many salespeople's statement that "drinking only alkaline water is good and drinking weakly acidic water is harmful" has no scientific basis, and it is misleading propaganda for the time being.
Eighth, read the instruction manual or user manual: Why do you have to read these two things?
Because there are too many benefits, it can reflect a lot of information very intuitively.
For example, does the water purifier need to replace the filter element?
Function of water purifier-Some high-end water purifiers will indicate the harmful substances that can be purified, as well as the experimental parameters and results in the user manual. You can be more clear that these words printed in the instruction manual and user manual have legal effect. If they don't achieve the effect, they will become the handle of peer attacks.
Ninth, look at after-sales: a good brand has a perfect after-sales system (however, this often requires real purchase of products, and problems arise when you realize whether you are satisfied or not when you use them)
If you read this, don't discuss such a sentence:
Why do the water purifiers produced by the same water purifier manufacturer have the same brand, different models and different prices?
I used to feel normal!
But by collecting and sorting out these materials, I suddenly realized! !
Can the low-priced model (so-called three-stage) water purifier produced by a factory meet the water purification requirements?
If you can!
So is it necessary to produce high-priced models (so-called class 5 or class 8) of water purifiers?
And much more expensive!
On the other hand-if the high-priced water purifier it produces can really meet the water purification standard?
Then selling low-priced models of water purifiers has become a deception to fool customers! !
This problem has been bothering me. ...
So: Personally, the price is not important and the brand is not important when choosing a water purifier. The only thing that matters is the effect!
Imagine: Even though you only spent 200 yuan to buy a water purifier, you spent 200 yuan to buy a water purifier that didn't achieve the expected effect! That would be a waste of 200 yuan. Do you think so?