How to protect yourself from infection? Water Filters

Medicine is becoming more and more advanced and mankind more and more sickly. This statement seems paradoxical only at first sight: until you remember about the ecology, worsening every year. Truly, “we heal with one hand and cripple with the other”! Man has so polluted the environment that literally everything needs to be thoroughly cleaned, above all the air, water, and food. Water, which was the very source of life on our planet, is the elixir of life for the human body. Being part of the blood, it delivers nutrients to the tissue cells and drains toxins, supports vital processes. That is why a human cannot live even a week without water, and for normal water metabolism an adult should drink 1.5-2 liters a day in addition to tea, coffee and soups. And at the same time it is water that can cause dangerous diseases.

If we are so rich, why are we so poor??

Blue lakes, bright waters of rivers, clear springs – all these notions gradually turn into poetic metaphors only. So-called surface sources rivers, lakes, reservoirs are polluted both by wastewater discharged by businesses in huge quantities and by petroleum products, pesticides, heavy metals washed off the ground by rains and spring streams. And what was not flushed away went into the ground and poisoned water in wells and springs. So the song “Give me key water to drink” can also be considered a poetic liberty.

Surface water sources account for 65-70% of the drinking water supply in America. What is natural: nature has generously endowed us with this wealth. And we, accustomed to treat carelessly what is given for free, not particularly concerned about its purity, while international experience shows that the cost of water treatment, which includes an analysis of water composition, installation of purification systems and its subsequent maintenance in working condition, account for an average of 5-7% of the cost of the house. Interestingly, other countries rich in rivers and lakes, such as Lithuania or Germany, have completely abandoned the use of surface water in their public water supply, replacing it with underground. Whether it is more profitable from the economic point of view to drill wells than to purify surface water is still a question, but there is no doubt that artesian water, which has passed through a 150-meter natural filter, can be drunk without any particular risk to health. With one caveat, however: Because of the high solubility due to the high pressure of the ground the salt concentration in artesian water is often too high.

It is fair to say that the quality of water treatment at municipal water treatment plants at least in New York meets international standards. But before the water reaches the consumer, it has to go many kilometers of dirty, rusty, overgrown with all sorts of sediment pipes, which is why it is so “enriched” with these secondary contaminants, that the results of purification at the municipal station is almost negligible.

There are two ways out of this situation: to purify water directly in the apartment or buy bottled water made at special plants. The second way is questionable, and not even so much because the regular supply of bottled water – an onerous task and not affordable to everyone, but because of the lack of confidence that the bottled water is not counterfeit. It is more reliable to purify water yourself with different filters. And from what should be purified tap water is clear enough: from sand, dirt particles, rust and suspended particles picked up in the pipes, as well as the chlorine introduced during the primary treatment to disinfect. In addition, the water may contain calcium and magnesium salts, giving it hardness, excessive iron and heavy metals.

Enemy No. 1

As for the water that we take directly from the open natural sources rivers, lakes, swamps , it can contain all sorts of contaminants. But the biggest danger for our health is hidden not in chemical admixtures, whose presence affects only with constant and continuous consumption of such water when the amount of accumulated in the body impurities reaches critical levels . Much more dangerous is the presence of bacteria and viruses in water: due to their inherent ability to actively reproduce in a favorable environment, which – alas! – The human body is also affected, even one sip can lead to intestinal infections, lesions of internal organs, skin, nervous system.

Chlorination

That you can’t drink such water raw is, of course, common knowledge. However, simply boiling does not get rid of “contamination” completely: all bacteria die only after prolonged sterilization. At municipal treatment plants disinfection is carried out by adding chlorine, a powerful disinfectant. But the sharp, unpleasant odor and taste that chlorine imparts to water makes it barely fit for drinking. But even worse – the consumption of chlorinated water can cause various diseases, ranging from simple skin irritation and ending with the appearance of malignant tumors.

The reason for this is the effect of chemicals formed when chlorine combines with organic substances dissolved in water. The more organic substances are present in water at the moment of chlorine addition, the less is left for water sterilization up to 10 % , and organoleptic properties unpleasant smell and taste, eye and mucous membrane irritation further deteriorate under the influence of new compounds. These organochlorine compounds are extremely toxic and carcinogenic, and can be absorbed through the skin and respiratory tract, not just by drinking, but also by bathing and showering. The use of chlorinated water for a long period of time several times increases the likelihood of serious chronic diseases, so chlorine water purification is an absolutely necessary measure.

If at first chlorination of water was considered a panacea, it is now treated as a necessary evil. Unavoidable, as this method still allows to disinfect water reliably all the way to the consumer. Can not be discounted and its cheapness, so that only recently chlorine was poured, not stingy, in all public institutions, and only these days respectable institutions began to use other methods.

Ozonation

In parallel with chlorination there was a search for other methods of disinfection. One of the most effective – ozonation – was used several years ago by the mayor of New York Yuri Klimov. m. Luzhkov wanted to replace chlorination, but these plans were most likely prevented by the high start-up cost of the method.

However, the benefits of ozonation are so obvious that its introduction into our lives is a matter of time. Ozone destroys enzyme systems of cells of microorganisms, not only possesses much higher sterilizing ability in comparison with chlorine, but also removes dissolved in water organic and chlororganic compounds. thus – unlike, for example, a reverse osmosis method – all salts necessary for the person remain. Besides, ozone helps to purify water from iron and manganese dissolved in it by transforming them into insoluble particles of such size that they can be easily removed by mechanical filters. As a result, the degree of purification in ozone plants from iron, manganese, suspensions, hydrogen sulfide, organic and organochlorine compounds, bacteria and viruses reaches 99,999%.

Guaranteed removal of any anthropogenic impurities herbicides, pesticides and other organics , the composition and concentration of which can vary rapidly, is very important in surface water treatment, allowing you to do without constant water analysis, required by other methods. At the same time ozonation is an absolutely ecologically pure method because no toxic compounds are formed in any of the processes and the ozone itself dissolved in water is not persistent ozone which does not take part in the reaction turns into the usual oxygen in a few minutes .

All of the above can be confirmed by the fact that ozone is used in the vast majority of water treatment systems in the developed countries of the world. The only thing that restrains the use of ozone plants in our country is high start-up expenses which, however, are quickly paid back as the operating costs are limited only by electricity no consumables .

UV irradiation

Rather complicated and big units for ozonation of water are good enough to be used in municipal plants, they can also be used in cottages, but it is rather problematic to fit even a specially designed for this purpose device into the apartment. The compact and inexpensive UV sterilizers make home water sterilization easy and convenient. However, ultraviolet sterilizers are not only used in the apartment: they are installed in cottages and public water supply systems, in laboratories and hospitals, industrial plants and restaurants.

The sterilizing effect of ultraviolet rays was discovered over 100 years ago by studying the solar spectrum, and it was soon realized that it was these rays that kept the balance of microorganisms on Earth. Initially UV radiation was used to sterilize the air primarily in operating rooms , but later it was also used to disinfect water.

The essence of the method lies in the fact that created by a mercury lamp, ultraviolet radiation with a wavelength of 253.7 nanometers prevents the reproduction of microorganisms by destroying DNA molecules. In this method – unlike chlorination and ozonation – no substances are added to the water, so an additional step, necessary in case of a wrongly chosen dose for cleaning of the remaining reagents, is not required in this case. The effectiveness of UV irradiation is very high, because not only the vegetative, but also spore forms of bacteria, viruses and other microorganisms are destroyed. The purity level is up to 99.99% and water that does not contain any impurities retains its taste and color. The method is absolutely safe, because the radiation from the lamp placed together with the treated water in a metal box does not pass outside.

The range of ultraviolet sterilizers, varying in purpose and capacity, is very wide: some models are installed on the entire flow of water into the house, others – only for apartments. The power is chosen so that the energy of ultraviolet radiation falling on each square centimeter of water complies with the norm. So, a 40W lamp is sufficient for the water consumption of a family of 3-4 people. In some models the concentration of the microorganisms in the inlet and outlet of the sterilizer is measured to monitor the effectiveness of the disinfection.

Decontamination with filters

Bacteria and viruses are so ubiquitous, tenacious and fecund that they can be in the water, even after the chlorination stage at the municipal plant. To prevent bacteria from multiplying in filters for purifying tap water to drinking water is added silver – a metal with a strong bacteriostatic effect. For water purification from open natural sources, where there is always the absence of various microorganisms and therefore only one bacteriostatic is not enough, disinfection is achieved with the help of special cartridges, which are added either iodine resins or carbohydrate mixtures of high reactivity.

This spring even American government thinks about water purity problems. Really, clean water – is health, which, as you know, can not buy a water filter to buy it is still possible, and you can choose between different cleaning systems. That’s why it’s important to decide how and what you want to purify your water from before you buy it.

What kind of water

Basically, it is important to know what impurities are in the water in your home and what it should be purified from. Ideal – if you don’t get lazy and do a tap water analysis to know exactly what’s flowing through your water supply. It is a solid knowledge of the composition of water will allow you to choose the best filter for its purification and get the best results.

Jug-type filters

The water seeps through a replaceable cartridge into the lower vessel.

Advantages:

The jug can be used anywhere: at home, in the country, at work, on the train, etc.d.

does not require an additional container to store water

one and the same housing can be installed cartridges for water with different properties in the city – for purification of tap water, in the country – to purify well water

sleek modern design.

Disadvantages:

Small volume of purified water

low filtration rate

low life of removable cartridges – requires regular purchase of cartridges.

Faucet Attachments

Faucet nozzles come in two types for ease of use:

– Nozzles that are connected to the faucet only for the duration of filtration

– Nozzles that are permanently on the faucet.

Advantages:

Compactness

low price

Can be used anywhere where there is a tap.

Disadvantages:

low filtration speed

small resource of filters.

Stationary flow-through filters

Composed of several bodies three or two , built into the water system and located under the sink, and a separate tap for drinking water. All filters in this category are cartridge filters, i.e.e. assume replacement of the replaceable element after the cartridge’s resource is exhausted.

Two-stage filters can be one-barrel and two-barrel. The first bulb has a mechanical purification cartridge, the second – carbon.

Three-stage filters with three cartridges, in addition to cleaning of water from mechanical impurities and cleaning with activated carbon from chlorine and organochlorine compounds have a third cartridge for softening water, removal of hardness salts.

Advantages:

fairly long resource

high degree of purification

high filtration speed.

Disadvantages:

troublesome installation

high price

Periodically it is required to change cartridges.

Desktop filters

All filtration stages take place in one body. The filter is connected to the tap with a threaded tap by means of a diverter- aerator or a quick release nozzle with a rubber seal. The type of connection depends on the type of filter and the diameter of the faucet. In principle, this is an alternative to stationary flow-through filters, if for some reason you can not connect the filter under the sink.

Advantages

:

Not bad speed of filtration

long resource.

Disadvantages:

To get clean water every time it is necessary to connect to the faucet

takes up space on your desk.

Reverse osmosis systems

Basically it is a mechanical purification of water on a molecular level, where the filtering thin film membrane allows only water molecules to pass through the smallest pores about 0,000 . It removes harmful substances such as magnesium, mercury, nitrates, nitrites, strontium, arsenic, cyanide, asbestos, fluorine, lead, sulfates, iron, chlorine, all bacteria and viruses from water.

Most often, manufacturers offer:

Five-stage reverse osmosis filter, where:

The 1st stage is pre-cleaning from mechanical impurities

The 2nd stage – purification with activated carbon from chlorine and organochlorine compounds

The 3rd stage – fine purification from mechanical impurities or additional purification by means of pressed activated carbon

The 4th stage – purification by membrane reverse osmosis method

5th step – carbon post-filter.

If the water pressure is less than 3 atmospheres, it is necessary to install a five-stage reverse osmosis filter with a pressure booster pump.

A four-stage reverse osmosis filter works like this:

1st stage – pre-treatment of mechanical impurities

2nd stage – cleaning with activated charcoal from chlorine and organochlorine compounds

The third stage is membrane cleaning reverse osmosis method

The 4th step is a carbon post-filter.

Besides, there are reverse osmosis flow filters and reverse osmosis filters with increased productivity increased productivity is achieved by installing additional membranes in combination with a pressure booster pump, which leads to an increase in the cost of the filter , reverse osmosis filters with mineralizers, with ultraviolet lamp, with a built-in sensor for the hardness salts content in purified water, etc.d.

Many reverse osmosis systems have a storage tank and faucet for clean water.

Advantages:

Suitable for both apartments and for use in cafes, restaurants, bars, recommended for use in coffee makers and ice makers

reliably retain all impurities

reduce water hardness without the need to regenerate the modules

potable water available at all times without the slightest effort.

Disadvantages:

deep cleaning can only be done with pre-treated water

the water at the output is almost completely devoid of salts – the debate has not subsided to this day, whether it is not harmful

Some filters have a limit on the minimum water pressure

A fairly high price of the installation.

In general, our salvation is in our hands. We can take care of ourselves, what water to drink – to wait for the grace of the authorities, or to allocate a certain amount of money to buy a suitable filter.

Irina Staroselskaya.