The technology that allows you to desalinate salt water and purify fresh water from impurities dissolved in it is called reverse osmosis. The question of what reverse osmosis brings - harm or benefit to our health - confronts everyone who wants to choose an effective device for drinking water purification. Consider the features, main disadvantages and advantages of such a filtration system, widely used in household filters, in order to determine the answer to this question.
The reverse osmosis system was developed over a century ago, but its real use began in the second half of the twentieth century. Initially, a similar filtration method was used in industry, and after it was possible to minimize costs and the size of the device, it began to be used in everyday life.
The debate about whether reverse osmosis is harmful to health or beneficial has not subsided for many years.
Natural and reverse osmosis
To understand the purposes and processes of reverse osmosis, consider the phenomenon of direct osmosis.
Osmosis is one of the most important natural phenomena. An example of this is the absorption of water by plant roots from the soil. A suspension with a lower concentration has a natural tendency to migrate into a solution with a higher concentration, passing through a semi-permeable membrane under pressure.
With reverse osmosis, we observe the process opposite to the phenomenon described above, when the liquid is freed from the particles dissolved in it. Osmosis occurs naturally without the use of energy. To carry out the reverse process, pressure must be applied to a more complex saline solution. In this case, the membrane plays the role of a kind of door that passes only substances whose dimensions are less than or equal to the diameter of water molecules (oxygen, chlorine and some other impurities freely penetrate through it).
This effect was discovered in ancient Greece, where at a primitive level it was used to desalinate liquids. However, reverse osmosis did not become widely used until the advent of synthetic membranes (cellular acetates) in the 1970s. And with the improvement of technology, it began to be widely used for home cleaning.
Water after reverse osmosis is considered environmentally friendly; according to its characteristics, it resembles melt water from ancient glaciers.
Filter operation process
The source water enters the reverse osmosis filter from the water tap, all separated impurities are drained into the sewer along with the drains. The cleaning process is divided into several stages:
- Pre-cleaning. At this stage, the water passes through three filters. The first polypropylene filter purifies the liquid from rust, sand, mechanical impurities, particles larger than 5 microns. The second, coal, will retain oil products, pesticides, chlorine, heavy metals, chemical and organic impurities. The third, one-micron, does not pass impurities larger than 1 micron.
- The passage of liquid through the membrane, which is the most expensive element of the filter. How long it will last depends on the quality of the incoming water. The pores in the membrane have a size of no more than 0.0001 micron. They allow water molecules, oxygen and some gases to pass through, which affect the taste of the liquid.
- Accumulation of purified water in a special tank made of enameled steel sheets.
- Passing through an additional filter, which serves as another guarantee of the purity of the liquid.
- spill through separate faucet embedded in the countertop or sink.
The process is shown in detail in the following video:
Characteristics of reverse osmosis filters
Reverse osmosis filters have the following features:
- They produce from 120 to 300 liters of pure water per day.
- The resource of use is from 4 to 15 thousand liters.To be clear, 4000 liters is enough for an average family of 4 for about 24 months.
- At the output, we get the purest water, purified from all kinds of impurities, bacteria and viruses, if their dimensions exceed the size of the membrane pores.
- The pre-filter cartridges need to be replaced every 6 months and the additional after-filters every 12 months. The operation of the reverse osmosis membrane is enough for 2-3 years. Any person can carry out the replacement process without additional knowledge and tools.
- Household filters are installed in apartments, private houses, cottages, small offices.
Benefits of home reverse osmosis systems
In addition to the fact that as a result of such purification we get water that is ideal for drinking, reverse osmosis has other significant advantages:
- Both tap water and other surface sources can be treated.
- To maintain a semi-permeable membrane in working condition, no chemicals are required. That is why reverse osmosis filters are considered safe and suitable for domestic use.
- These filters are durable devices. A family can use one filter for several years. The choice of such a system will positively affect the family budget.
- The storage tank of the reverse osmosis filter for 4-12 liters makes it possible to have at your disposal some supply of clean water.
- With the help of a filter, water is purified from harmful viruses and bacteria, such as hepatitis. Removal of harmful impurities from the water favorably affects the general condition of the body.
Unfortunately, in our world there are no perfect things, so reverse osmosis filters have their drawbacks:
- Semi-permeable membranes have the ability to quickly become clogged with heavy metal compounds, from which they need to be pre-cleaned. Otherwise, further work will not be possible.
- It is not recommended to connect the reverse osmosis filter to hot water, this will affect the efficiency of the process.
- The filling rate of the storage tank is quite low. The process can take up to 2 hours.
An excellent representative of reverse osmosis is the Atoll A-550 filter
The high-quality filter is equipped with a special mineralizer cartridge. This allows not only to make water clean, but also to saturate it with useful substances.
The performance of the Atoll A-550 filter is enough for a family of 4-5 people. Products are supplied with all necessary accessories, including a tap for drinking water.
Myths and truth about reverse osmosis
Among potential consumers, many legends, not supported by facts, are spreading by word of mouth about how harmful reverse osmosis is to the human body.
Myth No. 1. As a result of such purification, water is deprived of all minerals, it becomes “dead”
On the body itself, it turns into a weakly mineralized one (10–15 mg/l). While for the reference melt water from glaciers, the same indicator is 2–5 mg/l. At the same time, heavy metals, radionuclides, impurities of silt, sand, pathogenic bacteria, phenols and pesticides are removed during the cleaning process. Those who are worried about this can additionally install a mineralizer. Sometimes this device is sold complete with a filter.
Myth No. 2. Reverse osmosis water leaches the body of minerals it needs.
This claim has not been supported by any research. On the contrary, purified water works like a magnet that collects waste, rejected substances throughout your body and carries them to the lungs and kidneys for speedy elimination.
Myth number 3. Teeth will crumble from such water.
This statement came from an advertising company of one of the filter companies. They argue that long-term use of water devoid of fluoride will adversely affect the condition of the teeth. Practical studies have shown that consumers of treated water do not have such problems.
Myth #4. Purified water becomes tasteless.
This myth is actively spreading and confusing many consumers. On the one hand, this is true, because we are used to drinking chlorinated water with a high content of heavy metals. The metallic taste on the tongue is familiar to us and even pleasant. But crystal clear water should not have it.
With daily use of water purified by a reverse osmosis system, the taste of culinary masterpieces will be revealed in a new way, you will find out what your favorite coffee or tea really is, if you do not feel the taste of chlorine and iron when drinking them. The body will improve, stones and sand from the kidneys will begin to wash out.
