Tap water is considered safe, but many still prefer to “play it safe” by installing additional water filters or boiling it before drinking.
You can only find out how safe the liquid you drink is in a laboratory.
However, some signs of poor quality water can be determined by eye and thanks to the olfactory and taste receptors.
What's wrong with tap water?
Drinking tap water is undesirable and sometimes even dangerous. It contains too many chloride compounds. According to standards, chlorine should be up to 0.5 milligrams per liter of water. This amount is considered safe for humans and at the same time effective in the fight against bacteria and microbes.
Since 1904, humanity has been chlorinating water to protect against infections. Unfortunately, this is not an ideal solution - over 50 years of living with tap water, a person drinks 16 kilograms of chlorides, 2 kilograms of nitrates and 2 tablespoons of aluminum.
There is often rust in such water - water pipes in most cases are old and metal, iron oxide dissolves in water and is present in the form of small particles.
The direct result of drinking such water is kidney stones.
Tap water may be mixed with sewerage. According to the Russian Association of Water Supply and Sanitation, the wear and tear of water supply systems in Russia is approximately 58%. Sewer and water pipes laid side by side, in the same boxes, and they can rot so much that when you open the tap, you will see brown water flowing.
You should absolutely not drink it.
In addition, the quality of tap water depends on its hardness - the amount of calcium and magnesium salts, as well as impurities of iron and other minerals.
You should not drink tap water if:
The water is cloudy;
- if the shade is greenish, rusty, yellowish or any other;
- if the filter with a replaceable cassette has turned yellow (this may be due to worn-out pipes and, as a result, rust and iron getting into the water);
- water has a specific smell;
- after the water has settled, you see abundant sediment;
- the water has an unpleasant taste.
How to purify water at home?
I think it is no longer a secret to anyone that the water that flows from our tap does not have the quality and purity that our body needs. If you have a filter, all you have to do is change the cartridges regularly to be sure that the water you drink is extremely healthy.
But, just so you know, we can purify water at home without spending a lot of money on filters and cartridges, but using fairly simple methods.
Quality drinking water can be improved at home in several ways:
❧ Advocacy.
You need to pour tap water into glassware and stand for six to seven hours. During this time, volatile chlorine, along with other volatile impurities, will evaporate (it’s good if you periodically stir the water - this will help the “volatilization” processes occur more intensely).
However, heavy metal salts will not go away from settled water; best case scenario they settle to the bottom. Therefore, when you use this water, pour out 2/3 of its contents without shaking, so that the sediment at the bottom does not mix with more or less purified water.
❧ Filtration.
Pass the water through any filter. This can be a filter jug with a replaceable cassette, a faucet attachment and a filter for the cold water riser.
There are many types of water filters on the market, and prices vary widely.
When filtering water at home with capacitive filters, the main thing is to change the filter on time. Be sure to pay attention to the characteristics of the filter: how many liters of water it can purify, and control this amount.
If you do not change the filter in time, then the harmful components accumulated in it will go into the water being purified, that is, the water will not only not be purified, but the harmful components accumulated by the filter will also be added to it.
It is best to filter water at home with multi-level filters, but they also have serious prices.
Using such a filter, water is first purified from mechanical impurities, sediments, chlorine, colloidal solutions and iron oxides. And then, thanks to the reverse osmosis membrane of the filter, bacteria and viruses are removed from the water.
Multi-level filter purifies water by 99%. This figure is much higher than that of chlorinated water, not to mention the disadvantages of chlorination given above.
Water purified by such a filter is close in composition to spring water.
❧ Boiling
.
To boil water, use a regular kettle, not an electric one: the water will boil more slowly, but there will be much less scale. For cleansing, simple boiling is generally sufficient.
You need to boil water for at least 10-15 minutes. Only in this case a significant part of the microorganisms dies.
However, this method has its drawbacks. Our water often contains salts of heavy metals. When boiling, water evaporates and the concentration of salts in it increases. They are deposited on the walls of the kettle in the form of scale and lime and then enter the human body.
❧ Freezing.
This method will not purify large volumes of water, but it will be really clean. Pour tap water into plastic bottles(Not glass bottles and banks!)
Fill it with water, not reaching 1-2 cm to the edge, in order to leave free volume, since water increases its volume when it freezes. Remember glass bottles of water that burst in the cold? And put the bottle in the freezer.
When about half of the water in the bottle has frozen, drain the rest, remove the bottle with ice from the freezer and let the ice melt naturally.
Freezing is used mainly to remove excess salts from water. This method is based on the principle that pure water freezes at a higher temperature faster than water containing salts.
When pure water freezes first, what remains between the ice crystals is a so-called brine, that is, a mixture of water and salts. Accordingly, the “brine” is drained without allowing it to freeze, and clean ice is melted, obtaining purified water.
True, if the freezing temperature was too low, it may happen that not only pure water, but also the “brine” freezes.
Make sure that the ice in the bottle is transparent. Cloudy ice should not be used as it may contain harmful substances.
❧ About
silver cleaning
Silver ions, due to their bactericidal effect, perfectly purify water. You can use any silver item, preferably 999 fine: put it in a container of water and leave it overnight or for 8-10 hours.
Even an ordinary silver spoon dipped into a reservoir of water can improve its properties.
However, silver ions accumulate, as a result of which an excess of silver may occur in the body, and this will negatively affect metabolism.
So try to consume not only “silver” water.
❧ Cleansing with activated carbon.
Activated carbon is used in most filters used for water purification. After passing through it, the taste and smell of water improve, since it adsorbs most of the harmful impurities contained in the water.
You can make something like a filter yourself: just place activated carbon tablets (calculated at 1 tablet per 1 liter of water) in a bag made of cloth or gauze, put it in a container and pour tap water into it.
It is enough to keep the coal in water for 12 hours for the water to become purified.
This carbon filter needs to be changed 1-2 times a week.
❧ Cleansing with iodine.
Along with activated carbon, many purification systems also contain iodine. It has a detrimental effect on pathogens found in fresh water.
It works most effectively if the water room temperature or hot. If the collected tap water is clear, then 5 drops of iodine will need to be added per 1 liter; if it is cloudy, then 10 drops.
The water sits for half an hour, then you can drink it.
❧ Silicon purification.
Silicon, with its germicidal, antibacterial and anti-inflammatory properties, is the best natural filter for tap water. Silicon has a positive effect on the functioning of the gastrointestinal tract and metabolism, removes toxins, carcinogens and other substances harmful to health from our body.
You can purchase silicon in the pharmacy chain and in online stores/pharmacies.
The silicon is pre-washed well, placed in a container, and filled with water. Cover the jar with gauze and place it in the light, but away from direct sunlight, and leave for 2-3 days (at least a day).
Calculate the size of a silicon stone 3-10g per 1-5 liters of water. And do not drink the water to the bottom, carefully pour it into another vessel, leaving 3-5 centimeters of water with sediment.
Once a week it is necessary to clean the silicon crystals from plaque.
If there is no flint in the house, then water can be infused with Jerusalem artichoke. It has the highest percentage of silicon among vegetables - 8.1.
The second place in the amount of silicon is occupied by radishes. It contains slightly less silicon - 6.5%.
❧ Cleansing with shungite.
Lately Another stone called shungite is becoming popular for water purification. It is recommended to purchase large stones, then they will not need to be replaced with new ones, although, of course, once every six months they need to be thoroughly cleaned with a brush, a hard sponge or sandpaper.
Shungite water is prepared as follows: a 100 gram stone is placed in a liter of water (if you need more, then take more than one stone), the shungite water is infused for 3 days, no more, after which it is drained in the same way as when preparing silicon water.
Shungite water has contraindications: a tendency to cancer, blood clots, high acidity and diseases in the acute stage.
In which countries is it possible and in which countries is it not possible to drink tap water?
There are many states that monitor water quality throughout the entire water cycle. For example, in Holland they do not use chlorine at all, and in Austria or Switzerland about 90 percent of drinking water is chlorine-free.
In Finland you can also drink water straight from the tap. At treatment plants, it is treated with ferrous sulfate, then exposed only to ozone for disinfection.
In France, water is also treated with ozone, passed through sand filters, then ozonated again and purified using granular activated carbon filters. Authorities provide tax benefits those who cope with water purification best of all.
In Italy you can drink water not only from the tap, but even from a fountain on the street. The quality of water in the country is checked regularly.
TO tap water Germany applies the highest standards. Modern treatment facilities have been installed throughout the country.
The non-profit organization Water.org annually publishes a list of countries where drinking tap water is not recommended. The top three most dangerous countries are Afghanistan, Ethiopia and Chad. Things are not going well in Ghana, Rwanda, Bangladesh, Cambodia, Laos, India and Haiti.
based on materials
Tap water goes through several stages of processing, but still contains a large number of harmful chemical elements. This worsens a person’s health and well-being, and sometimes leads to various diseases. In addition, the quality of water affects the taste of cooked food and drinks. Impurities in its composition can easily spoil the taste and value of tea or coffee.
Chlorine, which is used to purify and disinfect tap water, kills dangerous bacteria and viruses. But at the same time it destroys protein structures human body, negatively affects the condition of the mucous membranes, eliminates beneficial bacteria and worsens the microflora in the intestines. This substance often contributes to the appearance and development of allergies.
Too hard water degrades the quality of clothes after washing. It can leave streaks and stains on clothes, making products rougher and tougher. To avoid these problems, you need to get rid of chlorine, purify and soften the water.
Filters for water purification
The most popular and practical cleaning method is using household filters. This can be a standard filter jug with a nozzle where you need to pour and settle water. Deeper cleaning will be carried out by stationary filters that are built into plumbing fixtures, or by special attachments on the faucet.
Such devices allow you to remove chlorine from tap water as much as possible and eliminate toxic and harmful elements. In any case, filters need to be changed at least once a month.
The big disadvantage of such devices is their high cost and the need to regularly change filters. However, they effectively purify water. As a result, it becomes safe for humans and suitable for drinking or cooking.
In addition, purified water will not leave marks and rust in the sink or bathtub, as well as scale on dishes. This will make it easier to wash the kettle and clean plumbing fixtures.
However, many people prefer to use homemade and easier methods of water purification. They will also come in handy if the filter breaks and you don’t have a new device at hand. Let's look at how to purify tap water without a filter.
Boiling and settling
Boiling is the most famous and easy method Sterilize and purify water at home. To do this, boil the water without a lid for at least 15 minutes. As a result, harmful compounds will leave along with the steam. However, the bleach will remain; moreover, it will turn into a more dangerous carcinogen that causes cancer.
Boiling has a number of other negative consequences. This process also kills beneficial elements, resulting in water becoming useless. In addition, after boiling, salts settle on the walls of the kettle or pan, which leave salt deposits and stains, as well as scale. Washing such dishes is quite difficult. How to clean the thermopot from scale, see.
Another easy method is settling. Pour water into any container and let it sit for eight hours. During this time, chlorine and other impurities will evaporate. To speed up the process, you can stir the contents regularly.
But settled water will still retain heavy metals. To remove these harmful substances, pour out 2⁄3 of the liquid without stirring or shaking the contents at the end and after settling.
Water purification using special means
- Pieces of silicon will purify water from impurities. First, rinse the pebbles in warm tap water, then put them in a glass jar and pour cold water at the rate of 3-10 grams of silicon per 1-3 liters of water. Place the jar in the light, but away from direct sunlight. After three days, the purified water can be drunk, but without using the contents from the bottom of the container. You can buy silicon at a pharmacy;
- Silver has effective cleansing properties. It softens and frees water from harmful microbes, viruses and chemical compounds, and kills bacteria. In this case, a silver spoon or coin is placed in a container of water and left for 10-12 hours. Silver-purified water will retain its beneficial properties for a long time;
- Shungite is a modern remedy that can also be bought at the pharmacy. To clean, 100 grams of stone are placed in a liter of water and left for three days. Choose large stones and do not use water from the bottom of the container. Shungite can be used many times by cleaning the stone once a year with a hard sponge, brush or sandpaper. However, this method is not recommended for people with increased acidity, With oncological diseases, blood clots and during exacerbation of chronic diseases;
- Magnets are another way to purify water at home. However, it is not effective enough, since it only collects iron salts. And bleach and most of germs will remain in the water. To clean, magnets are wrapped around the dishes and left for five hours;
- Activated carbon will effectively replace filters, because this very product is used in the manufacture of cleaning devices. It neutralizes the unpleasant smell of rusty pipes and bleach, removes harmful and toxic substances. Wrap the tablets in gauze and place in a container of water at the rate of one tablet per liter of water. In just eight hours the water will be clear!
Is it good to freeze water?
Freezing is a popular, most effective and efficient cleaning method today. It has been proven that melt water contains much less impurities and harmful substances than from the tap. It restores the body, improves performance and gives strength, helps with allergies, dermatitis and skin itching, with stomatitis and asthma.
To freeze, pour water into a saucepan with a lid and a plastic container, leaving some free space at the top. You cannot use glass containers; it is not recommended to take plastic bottles, as they are hazardous to health.
A suitable option would be special freezer bags or containers made of high-quality food-grade plastic. These dishes are convenient to use for freezing and storing food or water. In addition, high-quality plastic dishes are easy to wash and, if necessary, can be used. At the same time, food-grade plastic is safe for humans.
To get the maximum benefit from melt water, when the water in the container freezes halfway, drain the unfrozen part. And the remaining ice can be melted and used as drinking water. Freshly defrosted water is considered the most useful and healing.
Traditional methods of purifying tap water
- Table salt in the amount of one tablespoon is placed in two liters of water and left for 20-25 minutes. During this time, the water is purified from salts, heavy metals and dangerous microorganisms. However, it is not recommended to drink such liquid every day;
- Plant components, including juniper branches, onion peel, willow bark or bird cherry leaves also effectively purify water. Place the product in the liquid and leave for at least 12 hours;
- A bunch of rowan produces purified water, equal in quality after purification with activated carbon or silver. To do this, rowan is immersed in water for three hours;
- The wine method should be used with extreme caution, as it can spoil the taste of drinking water. To avoid this, strictly follow the cleaning rules. In this case, add one part of dry white wine to two parts of water, mix and leave for three to four hours;
- Vinegar and iodine purify water, but can also give an unpleasant taste. In addition, after cleaning, some chlorine compounds and microbes still remain in the liquid. Place a teaspoon of vinegar per liter of water or add three drops of 5% iodine and leave for six hours.
The quality of water depends on the chosen purification method and on how much you settle the liquid or use filters. Some people replace tap water with distilled water. This liquid does not contain harmful substances and compounds, but it has no taste and, if consumed frequently, washes out beneficial salts and minerals from the body.
The choice of purification method depends on the composition of the water itself and the available capabilities.
Tap water supplied to apartments has different levels of harmful components.
That's why there is a need to select the optimal method of post-treatment, with which you can effectively reduce the amount of harmful substances.
In some cases, a person has to use water from natural sources. In this case, the task of disinfection comes to the fore.
In order to objectively make a choice in favor of one or another cleaning method, it is necessary to have an idea of its advantages, disadvantages and application algorithm.
Main methods home water purification without filter are:
- Advocacy;
- Boiling;
- Freezing;
- Distillation method;
- Carbon adsorption;
- Cleansing with silver;
- Iodization;
- Shung grafting;
- Silicon processing;
- Use of tourmaline;
- Herbal cleansing.
Advocacy
This the most easily accessible and cost-effective way tertiary treatment.
The result of this process is the volatilization of chlorine gas and the precipitation of heavy metal salts.
Defending is considered a simple but ineffective technique. Only the upper third of the water volume is freed from chlorine. The lower layers contain increased amounts of pollutants.
According to the rules, water must be kept in an open container for at least 24 hours. After this, it is carefully drained to less than half the volume.
The settled water, without any further treatment, can be used to water plants or fill an aquarium.
Boiling
A simple, convenient, cheap and relatively effective method. The main purpose of boiling is to destroy pathogenic microorganisms, chlorine and low-temperature gases (radon, ammonia).
However, the method also has its disadvantages:
To level out Negative consequences, It is recommended to use already settled liquid for boiling and limit the boiling time to 15 minutes. In this case, the water container must be open.
Attention! Not all microorganisms die when briefly heated to 100 degrees!
Most pathogenic bacteria (staphylococcus, typhoid bacillus, Shigella, Koch's bacillus and others) They die when boiled within a few seconds. However, there are also more resistant microorganisms.
An example would be the hepatitis A virus, which dies in boiling water only after 5 minutes. Anthrax spores, which can withstand boiling, show even greater endurance.
Freezing
The method is based on a physical and chemical phenomenon, according to which crystal clear water first turns into ice.
The substance with impurities freezes last. The instructions for using freezing are simple.
Water is poured into an open container and placed in freezer. When half of the liquid freezes, take out the ice and drain the rest. Thawed ice is ready for use without any additional processing.
Distillation method
Obtaining pure, salt-free water is based on distillation. The technological process in everyday life requires special equipment - a distiller. It is a system consisting of a container in which water is heated, a tube through which steam moves, and a container in which the purified liquid is collected.
The method has two undeniable advantages:
- There is almost complete liberation from salts.
- When heated, microorganisms die.
However, there are also disadvantages:
- Light organochlorines are carried along with the steam.
- Water loses biologically essential microelements.
Important! Long-term consumption of distilled water leads to the leaching of potassium, iron, manganese and other physiologically important elements from the body.
Carbon adsorption
Thanks to the porous structure the substance actively absorbs mineral and organic impurities.
The cleaning option is simple and convenient, but it also has disadvantages. The sorption capacity of coal is limited.
Home instructions for use are simple. Several tablets are placed in a gauze bag and placed in a vessel with water.
The sorbent dosage is 1 tablet per 1 liter of liquid. Functional analogues of coal are crushed coconut shells or ground fruit tree seeds.
Silver
Silver is a metal with pronounced bactericidal properties. This is the basis for its use in biological treatment of liquids.
In terms of its level of action, silver is equivalent to bleach. This metal is even used in swimming pools for disinfection. It is known that water supplied to international space stations is preserved with silver.
For bio-purification at home, it is enough to place a silver object in a container of water.
But with this method, the proportion of metal passing into water will be low.
To get a more pronounced effect, it is necessary to use a solution where silver is in ionic form.
Carefully! It has been scientifically proven that in high concentrations silver has a negative effect on living cell. Therefore, it is undesirable to abuse this method.
Iodization
Iodine is widely used in medicine as a disinfectant. This property is also used for domestic purposes. The advantage of iodine is its high bactericidal ability.
However, along with this advantage, the method has significant disadvantages.
- Firstly, only biological treatment occurs.
- Secondly, the water acquires a characteristic iodine odor.
This greatly limits the use of iodization. An analogue of this method can be bromination. But the use of bromine is expensive, so it is not widely used at home.
Shunging
Shungite is a fossil mineral with unique physical and chemical properties.
This is an excellent sorbent that absorbs:
- chlorine,
- nitrates,
- heavy metals,
- organics.
Shungite has bactericidal properties. The mineral contains a large number of trace elements, thanks to this, the water is mineralized when infused.
Important to remember that the mineral has limited sorption capacity. Microbes, accumulating inside the stone, are able to live there. Therefore, the shungite filter should be periodically replaced with a new one.
Silicon processing
To find a suitable water purification method, you need to know which pollutants are present in the greatest quantities.
Before starting household post-treatment of tap water or natural water, it is worth collecting information about its composition.
The ideal option is laboratory analysis or home tests. Such data will help you navigate in choosing the right water purification method.
Important! If the same container is used for cleaning and disinfection, it must be washed periodically. In the light, water “blooms”, that is, green algae appear in it, which remain on the walls of the vessel and deteriorate the quality of each subsequent portion of water.
Conclusion
The quality of water supplied to apartments and houses is regulated by sanitary and hygienic standards. Despite state control, water supplied to consumers does not always meet standards. Household methods of post-purification help to cope with the emerging problem.
The presented review makes it possible to objectively evaluate the entire range of methods and choose the most suitable one in specific conditions. Cleaning at home allows you to save on expensive modern ones.
With proper implementation and combination of methods, the output can be water with good organoleptic and chemical characteristics.
Physico-chemical methods of water purification
As the name suggests, water purification methods in this group combine chemical and physical effects on water pollutants. They are quite diverse and are used to remove a wide variety of substances. These include dissolved gases, fine liquid or solid particles, heavy metal ions, as well as various substances in a dissolved state. Physico-chemical methods can be used both at the stage pre-cleaning, and at later stages for deep cleaning.
The variety of methods in this group is great, so the most common of them are given below:
- flotation;
- sorption;
- extraction;
- ion exchange;
- electrodialysis;
- reverse osmosis;
- thermal methods.
Flotation, as applied to water treatment, is the process of separating hydrophobic particles by passing a large number of gas bubbles (usually air) through water. The wettability of the separated pollutant is such that the particles are fixed on the interface between the phases of the bubbles and, together with them, rise to the surface, where they form a layer of foam that can be easily removed. If the separated particle turns out to be larger in size than the bubbles, then together they (particle + bubbles) form a so-called flotation complex. Flotation is often combined with the use of chemical reagents, for example, those that are sorbed on pollutant particles, thereby reducing its wettability, or that are coagulants and lead to the enlargement of removed particles. Flotation is primarily used to purify water from various petroleum products and oils, but it can also remove solid impurities, the separation of which is ineffective by other methods.
There are various options for implementing the flotation process, which is why the following types are distinguished:
- foam;
- pressure;
- mechanical:
- pneumatic;
- electric;
- chemical, etc.
Let us give an example of the operating principle of some of them. A widely used method is pneumatic flotation, in which the formation of an upward flow of bubbles is created by installing aerators, usually in the form of perforated pipes or plates, at the bottom of the tank. The air supplied under pressure passes through the perforations, due to which it is split into separate bubbles, which carry out the flotation process itself. In pressure flotation, the stream of purified water is mixed with a stream of water supersaturated with gas and under pressure, and fed into the flotation chamber. With a sharp drop in pressure, gas dissolved in water begins to release in the form of small bubbles. In the case of electroflotation, the process of bubble formation occurs on the surface of electrodes located in the water being purified when an electric current flows through them.
Sorption methods are based on the selective absorption of pollutants in the surface layer of the sorbent (adsorption) or in its volume (absorption). In particular, to purify water, an adsorption process is used, which can be physical and chemical in nature. The difference lies in the way the adsorbed pollutant is retained: through molecular interaction forces (physical adsorption) or through the formation of chemical bonds (chemical adsorption or chemisorption). Methods of this group are capable of achieving great efficiency and removing even low concentrations of pollutants from water at high flow rates, which makes them preferable as post-treatment methods at the final stages of the water purification and water treatment process. Sorption methods can remove various herbicides and pesticides, phenols, surfactants, etc.
Substances such as activated carbons, silica gels, aluminum gels and zeolites are used as adsorbents. Their structure is made porous, which significantly increases the specific area of the adsorbent per unit volume, which is why the process is more efficient. The adsorption purification process itself can be carried out by mixing the water to be purified and an adsorbent, or by filtering water through a layer of adsorbent. Depending on the sorbent material and the pollutant being extracted, the process can be regenerative (the adsorbent is used again after regeneration) or destructive, when the adsorbent must be disposed of due to the impossibility of its regeneration.
Water purification using the liquid method extraction consists in the use of extractants. In relation to water purification, an extractant is an immiscible or slightly miscible liquid with water that dissolves pollutants extracted from water much better. The process is carried out as follows: the purified water and the extractant are mixed to develop a large phase contact surface, after which a redistribution of dissolved pollutants occurs in them, most of which passes into the extractant, then the two phases are separated. The extractant saturated with extracted pollutants is called extract, and purified water is called raffinate. The extractant can then be utilized or regenerated depending on the process conditions. This method mainly removes organic compounds such as phenols and organic acids from water. If the extracted substance is of a certain value, then after regeneration of the extractant, instead of disposal, it can be usefully used for other purposes. This fact promotes the application of the extraction method of purification to wastewater from enterprises for the extraction and subsequent use or return to production of a number of substances lost with wastewater.
Ion exchange It is mainly used in water treatment for the purpose of softening water, that is, removing hardness salts. The essence of the process is the exchange of ions between water and a special material called an ion exchanger. Ion exchangers are divided into cation exchangers and anion exchangers depending on the type of exchanged ions. From a chemical point of view, an ion exchanger is a high-molecular substance consisting of a framework (matrix) with big amount functional groups capable of ion exchange. There are natural ion exchangers, such as zeolites and sulfonated carbons, which were used in the early stages of the development of ion exchange purification, but now artificial ion exchange resins have become widespread, significantly superior to their natural counterparts in ion exchange ability. The ion exchange cleaning method has become widespread, both in industry and in everyday life. Household ion exchange filters, as a rule, are not used to work with heavily contaminated water, so the resource of one filter is enough to purify a large amount of water, after which the filter must be disposed of. At the same time, during water treatment, the ion-exchange material is most often subject to regeneration using solutions with a high content of H + or OH – ions.
Electrodialysis is a complex method combining membrane and electrical processes. It can be used to remove various ions from water and carry out desalting. Unlike conventional membrane processes, electrodialysis uses special ion-selective membranes that allow ions of a certain sign to pass through. The apparatus for carrying out electrodialysis is called an electrodialyzer and is a series of chambers separated by alternating cation-exchange and anion-exchange membranes, into which purified water flows. In the outer chambers there are electrodes to which the D.C.. Under the influence of the emerging electric field The ions begin to move towards the electrodes according to their charge until they encounter an ion-selective membrane with a matching charge. This leads to the fact that in some chambers there is a constant outflow of ions (desalting chambers), while in others, on the contrary, their accumulation is observed (concentration chamber). By dividing the flows from different chambers, it is possible to obtain concentrated and desalted solutions. The undeniable advantages of this method lie not only in purifying water from ions, but also in obtaining concentrated solutions of the separated substance, which allows it to be returned back to production. This makes electrodialysis especially popular at various chemical plants, where some of the valuable components are lost along with the wastewater, and the use of this method is made cheaper by obtaining a concentrate.
Additional information on electrodialysis
Reverse osmosis refers to membrane processes and is carried out under pressure greater than osmotic. Osmotic pressure is an excess hydrostatic pressure applied to a solution separated by a semi-permeable partition (membrane) from a pure solvent, at which diffusion of the pure solvent through the membrane into the solution stops. Accordingly, at an operating pressure above the osmotic pressure, a reverse transition of the solvent from the solution will be observed, due to which the concentration of the dissolved substance will increase. In this way, dissolved gases, salts (including hardness salts), colloidal particles, as well as bacteria and viruses can be separated. Reverse osmosis plants are also distinguished by the fact that they are used to obtain fresh water from sea water. This type of treatment is successfully used both in domestic conditions and in wastewater treatment and water treatment.
Additional information on reverse osmosis and reverse osmosis systems
Thermal methods are based on the effect of elevated or reduced temperatures on the purified water. Evaporation is one of the most energy-intensive processes, but it produces water high degree purity and a highly concentrated solution with non-volatile contaminants. Also, the concentration of impurities can be carried out using freezing, since pure water begins to crystallize first, and only then the rest of it with dissolved pollutants. By evaporation, as well as by freezing, it is possible to carry out crystallization - the separation of impurities in the form of crystals that precipitate from a saturated solution. As an extreme method, thermal oxidation is used, when the purified water is atomized and exposed to high-temperature combustion products. This method is used to neutralize highly toxic or difficult to degrade pollutants.
Every person needs water to live, we drink it, use it to prepare food for ourselves, and wash our bodies with it. We are accustomed to taking it for granted that when we open the tap, we get water from the tap. But this water is far from ideal quality, so it requires additional purification. But how can you do this at home without expensive industrial multi-level filters?
What's wrong with tap water?
Water - this is a source of not only liquid, but also mineral salts for the body; a person cannot do without water, it must always be in our homes. But tap water is intended for domestic needs - washing dishes, bathing and laundry. It is better not to use it for drinking; it contains too many chloride compounds. They are added to water to disinfect it from viruses and microbes that can be dangerous to human health.
However, chlorine itself is unsafe: it negatively affects body proteins, irritates the mucous membranes of the digestive system, disrupts the intestinal microflora and causes general allergization of the body. In addition, chlorine in water also forms by-products that are potentially dangerous to the body and require prior removal from it.
In addition, the quality of tap water also depends on its hardness - the amount of calcium and magnesium salts, as well as impurities of iron and other minerals. If there are a lot of salts, this can negatively affect the kidneys; if there are few minerals, the body will suffer from a lack of them, the skeleton will become more fragile, weakness will appear, hair loss and dry skin.
The taste of food cooked with tap water and the taste of food cooked with purified water are very different. Fragments of rust, dirt, scale and other impurities can get into the soup or second dish from tap water. A coffee or tea in general will be frankly spoiled, despite the most expensive varieties of the raw materials themselves.
By the way, it has been proven that even strong chlorination does not kill Giardia cysts, and you can easily catch them when drinking raw water. Therefore, do not neglect at least the simplest methods of water purification, then your health will be significantly supported.
Water purification methods
We present to your attention the most simple ways water purification.
Boiling water
This method, of course, will remove germs and viruses from it, but not chlorine compounds. When the temperature rises, chlorine reacts with salt impurities in water and converts them into chlorine compounds, which are unsafe for health. In addition, boiling deposits some of the salts on the walls of the dishes; look into your kettle and see how many of them are there.
Water settling
This is one of the simple and cost-effective ways to purify water from chlorine. Chlorine is a volatile compound; when water sits for 6-8 hours, all the chlorine dissolved in it will evaporate. Stir the water several times - this will help the chlorine separate more actively.
The disadvantage of this method is that heavy metal salts are not removed during settling.
Freezing water
One of the most effective ways One way to purify water at home without the use of special devices is to freeze it.
How to purify tap water?
Water is a special compound, a solution of ions, it contains an admixture of so-called “heavy” deuterium water. These are special heavy hydrogen ions from water that negatively affect the health of the elderly and children. Such water freezes before the total mass, remove the needle mesh from the deuterium water, and freeze the rest in an open plastic container (it is better not to freeze glass containers: when water freezes, it expands and the glass may burst).
After freezing, the ice will have a layered appearance - at the edges there will be cloudy ice with impurities and harmful compounds, in the center there will be pure water. This cloudy ice defrosts faster, is drained, and the core is used for drinking and cooking. The only drawback of melt water is that it contains few useful salts; to drink it, it is better to add 100 g of mineral water to a liter of such water.
Water purification methods (continued)
Coal cleaning
This method of water purification is known to avid travelers and military personnel. To clean a glass of water, you need 1 tablet of regular pharmaceutical charcoal - it is pounded, wrapped in gauze and filled with water, after 15 minutes the water is filtered through a fine sieve. This water tastes good and has no odor. However, coal does not protect against viruses and microbes - in wild conditions such water still needs to be boiled additionally.
Silver cleaning
Silver is believed to neutralize microbes and some metal salts, although silver's cleaning power has been greatly exaggerated. It is recommended to leave a silver item - a spoon or a special pendant - in a container with water overnight. Water sedimentation and disinfection work simultaneously.
Water purification with magnets
Another one of traditional methods, which has questionable effectiveness. It is recommended to surround a container with water with magnets and leave the water for several hours. Option: wrap magnets around the pipe that supplies water to the tap. This method does not protect against chlorine and microbes, but theoretically it can purify water from iron and its salts due to magnetization.