The problem of water purification covers issues of physical, chemical and biological changes during the treatment process in order to make it suitable for drinking, i.e., purification and improvement of its natural properties.

The main methods of water purification for domestic and drinking water supply are clarification, decolorization and disinfection.

Water clarification by sedimentation of suspended substances. This function is performed by clarifiers, settling tanks and filters. In clarifiers and settling tanks, water moves at a slower speed, as a result of which suspended particles precipitate. In order to precipitate tiny colloidal particles, which can remain suspended indefinitely, a coagulant solution (usually aluminum sulfate, ferrous sulfate or ferric chloride) is added to the water. As a result of the reaction of the coagulant with salts of polyvalent metals contained in water, flakes are formed, which entrain suspended matter and colloidal substances during sedimentation.

Coagulation of water impurities is the process of enlargement of the smallest colloidal and suspended particles, which occurs as a result of their mutual adhesion under the influence of molecular attraction forces.

Filtration is the most common method of separating solids from liquids. In this case, not only dispersed particles, but also colloids can be isolated from the solution.

During the filtration process, suspended substances are retained in the pores of the filter medium and in the biological film surrounding the particles of the filter material. Water is freed from suspended particles, coagulant flakes and most bacteria.

Discoloration of water, i.e., the elimination or discoloration of various colored colloids or completely dissolved substances can be achieved by coagulation, the use of various oxidizing agents (chlorine and its derivatives, ozone, potassium permanganate) and sorbents (activated carbon, artificial resins).

Disinfection of water, or its disinfection, consists of completely freeing water from pathogenic bacteria. Since neither settling nor filtering provides complete release, chlorination and other methods described below are used to disinfect water.

Traditional water purification methods do not allow the removal of many types of contaminants (especially those contained in dissolved water) that can be found in surface water sources. These methods often do not produce water of standard quality, even when removing naturally occurring tastes and odors is required. In this regard, they are trying to use additional methods of water treatment: oxidation, sorption, ion exchange, physical methods, etc. For the purposes of domestic and drinking water supply, as a rule, it is necessary to treat a large amount of water, in addition, the cost of its treatment should be low. Therefore, in water supply practice, only the first two methods are currently used: oxidation and sorption.

Oxidative method of water purification

Oxidizing agents have long been used in water treatment technology, mainly due to their bactericidal effect. At the end of the last century, the first experiments were carried out on water disinfection with chlorine and azone. Oxidizing agents are also used to remove the color of water, its tastes and odors, i.e. organic substances of natural origin. Along with gaseous chlorine and ozone, various chlorine-containing products (bleach, hypochlorites, chlorine dioxide) and potassium permanganate are used. These oxidizing agents have different redox potentials. However, the effectiveness of their action is determined not only by the value of the redox potential, but also by other factors that must be taken into account when assessing the effect of the oxidizer on certain types of contaminants. Such factors include the rate of interaction of the oxidizer with substances removed from the water, as well as the peculiarities of interaction that appear in some cases. It must be borne in mind that purification of water from organic compounds with the help of oxidizing agents is achieved through their decomposition, i.e. transfer to other connections. Purification from inorganic compounds, including metal ions, can be achieved only if the latter are converted into an insoluble form by the action of oxidizing agents. Thanks to this, they can be transferred from water using sedimentation, filtration, etc.

The most typical oxidizing agents and their interaction with typical types of water pollutants.

Chlorine. As is known, the interaction of chlorine with water proceeds according to the equation

Cl2 + H2O ↔ HCl + HClO

Hypochlorous acid formed as a result of hydrolysis of chlorine dissociates according to the equation

HClO ↔ H+ + OCl–

Chlorine is a good disinfectant. Its bactericidal effect is manifested against bacteria and some types of viruses. The disinfecting effect depends on the dose of chlorine, the time of its contact with water, the degree of water contamination and other conditions. Various chemical compounds can react with chlorine.

Natural humic substances, which cause the color of water, are subject to oxidation by chlorine. There is evidence that chlorination disrupts the stability of colloidal particles of aqueous humus, promoting their coagulation.

Chlorine reacts relatively easily with phenols. Research conducted at the Institute of Colloidal Chemistry of Water made it possible to establish that among the class of phenols, the most resistant to chlorine are monohydric phenols - oxybenzene, cresol, naphthol. Diatomic phenols (pyrocatechol, resorcinol, hydroquinone) and triatomic phenols (phloroglucinol, resorcinol, hydroquinone) are destroyed much more intensively by chlorine.

Experiments were carried out to determine the nature of the interaction of chlorine with phenol (oxybenzene). These data show that at low doses of chlorine phenol is not destroyed, although consumption of the oxidizing agent is observed. Apparently, at this stage, the formation of chlorinated phenol derivatives occurs, which was confirmed by the appearance of a typical “pharmacy” smell of water. With an increase in the dose of chlorine, the amount of phenol begins to decrease, which indicates its destruction. When phenol is completely destroyed, the consumption of chlorine stops. Based on the amount of reacted chlorine, it can be calculated that in this case oxidation occurs mainly to maleic acid. In this case, a certain excess of chlorine is necessary for the reaction to occur. Features of the interaction of chlorine with phenol are the formation of undesirable chlorine derivatives with insufficient doses of chlorine and the need for a significant excess of chlorine to destroy them, which in practical conditions requires a special process for dechlorinating water.

In a study carried out by Burtschel and his co-workers, it was found that most phenol chlorinated derivatives have an unpleasant odor, especially 2-chlorophenol, 2,4-dichlorophenol, 2,6-dichlorophenol and trichlorophenol.

The interaction of chlorine with ammonia is very specific, since the reaction between them proceeds quite quickly with the formation of chloramines. For example, chlorine reacts with ammonia approximately 100 times faster than with phenol. Depending on the reaction conditions, including the ratio of chlorine and ammonia concentrations, various chloramines can be formed: monochloramines (NH4Cl), dichloramines (NHCl2) and trichloramines (NCl3).

Chloramines, like chlorine, are oxidizing agents and have a bactericidal effect, which manifests itself, however, much more slowly and weakly. In the presence of bound chlorine, it is recommended to disinfect water with increased doses of chlorine and with longer contact with the treated water compared to free chlorine. Chloramines react much more slowly with organic substances than chlorine. Therefore, in practice, ammonia is often specially added to water in order to “bind” chlorine into chloramines and prevent the formation of unwanted organic chlorine derivatives, such as chlorophenols. The same example is used in cases where it is necessary to prolong the bactericidal effect of chlorine. However, if it is necessary to carry out deep and rapid oxidation of contaminants in the water and if chloramines are inevitably formed in the presence of ammonia in the treated water, in practice they resort to excessive chlorination.

A large number of studies are devoted to the issue of studying the interaction of chlorine with pesticides. Available evidence shows that chlorine does not oxidize most chlorinated organic pesticides well, and when this reaction occurs, toxic products can be formed: for example, aldrin, when oxidized by chlorine, is converted to deldrin, which is more toxic than the original product.

Organophosphorus pesticides are oxidized by chlorine somewhat better, however, even here more toxic products can be formed compared to the original substance. Thus, when chlorine interacts with parathion, the latter turns into a more toxic product - paraoxon.

There is a significant group of organic chemical compounds with which chlorine practically does not interact or interacts very weakly. Such compounds include synthetic surfactants, in particular chlorine sulfonol, compounds found in oils and petroleum products, etc. Free chlorine is capable of oxidizing some metals, converting them into sparingly soluble compounds, due to which they can be removed from water. For example, divalent iron is relatively easily oxidized by chlorine.

Chlorine dioxide is a poisonous, explosive gas, highly soluble in form. Under normal conditions, one volume of water dissolves about 30 volumes of chlorine dioxide. The most commonly used method is based on the oxidation of sodium chlorite with chlorine:

2NaClO2 + Cl2 → 2 smells. Chlorine dioxide is very energetic ClO2 + 2NaCl

Along with the high bactericidal effect of chlorine dioxide, many researchers also note the effectiveness of its use to eliminate tastes and odors. Chlorine dioxide reacts very vigorously with phenols. The rate of this reaction is many times higher than the rate of oxidation of phenol with chlorine. Researchers have found that chlorine dioxide, like chlorine, is an ineffective reagent in relation to petroleum products and will not remove the tastes and odors caused by them. Chlorine dioxide reacts poorly with synthetic surfactants. Unlike chlorine, chlorine dioxide does not interact with ammonia, and therefore the presence of the latter in water does not affect its oxidizing effect. Noting that chlorine dioxide has an advantage over other oxidizing agents when purifying water from manganese, since the oxidation reaction of manganese with chlorine dioxide occurs almost instantly.

Potassium permanganate. Although this reagent began to be used for water purification a long time ago, it has only in recent decades become widespread in a number of countries, especially when it is necessary to reduce tastes and odors of water and remove divalent iron and manganese from it.

A special feature of potassium permanganate is that, acting as an oxidizing agent, it is itself reduced to manganese dioxide. Some researchers attribute an important role to manganese dioxide in the process of removing contaminants from water, believing that it forms a finely dispersed sediment in water that can adsorb certain types of contaminants on its surface, thereby increasing the overall effect of water purification. In this case, the dose of permanganate can be selected in the simplest way based on the specific violet color inherent in the solution of the permanganate itself.

Potassium permanganate is capable of oxidizing a very limited amount of pesticides. When potassium permanganate interacts with pesticides, as well as when exposed to chlorine, products that are more toxic than the pesticides themselves can be formed.

There are conflicting opinions regarding the bactericidal effect of potassium permanganate. Some researchers believe that potassium permanganate has a good bactericidal effect and that this allows, when using it to eliminate tastes and odors, to avoid treating water with chlorine. Other researchers note that potassium permanganate in doses usual for eliminating water odors has a weak bactericidal and virucidal effect.

Ozone is a colorless gas with a strong, peculiar odor, toxic, explosive, and relatively easily spontaneously decomposes, turning into oxygen, releasing energy. In clean and dry air, its decomposition occurs more slowly than in humid and polluted air. Ozone decomposes even faster in water at high pH values. It is a very weak oxidizing agent.

Ozone is produced by applying a quiet electrical discharge to oxygen in the air or pure oxygen in special generators. The product produced is not pure ozone, but a mixture of it with air or oxygen.

To create conditions for the interaction of ozone with substances in water, it must be transferred from the gas phase into water and dissolved in it. For this purpose, various methods of displacing the ozone-gas mixture with water are used: bubbling, injection using emulsifiers, mechanical displacement, etc.

Numerous studies have established that ozone has a high bactericidal effect. In addition, a stronger effect of ozone on spore forms was noted, as well as a faster disinfection effect of ozone compared to chlorine. At the same time, water treatment with ozone has its own characteristics, which often do not allow its advantages as a disinfecting reagent to be realized. In this regard, sometimes, along with treating water with ozone, before supplying it to the network, it is subjected to additional disinfection with chlorine.

Ozone, compared to chlorine and potassium permanganate, oxidizes organophosphate pesticides much more deeply. It interacts poorly with organochlorine pesticides, although in large doses it can destroy these compounds.

It has been established that ozone, when reacting with humic substances, usually forms colorless compounds. However, there is evidence that when the pH of the medium changes, the color is sometimes restored.

The literature also notes that under the influence of ozone, the stability of some organic compounds changes and they become able to be retained during filtration.

Summarizing the data presented regarding the effect of oxidizing agents on various types of contaminants and water impurities, it should be noted that the oxidation method cannot be considered as universal and sanitary reliable. Even such a strong oxidizing agent as ozone does not guarantee water purification from all types of contaminants that may be found in surface water sources. A significant disadvantage of oxidizing agents is that they do not remove contaminants from water, but only convert them into other compounds. In this case, products can be formed that worsen the organoleptic indicators of water quality (for example, color appears, odor appears) and are even toxic. Therefore, oxidizing agents can be used only in cases where there is complete confidence that their impact on water pollution will not lead to the formation of undesirable products. However, even in this case, difficulties may arise in the practical use of oxidizing agents, associated with the need to select and maintain their dose depending on the type and concentration and due to the duration of many water analyzes and, consequently, the impossibility of operational control over the effect of its purification.

Water purification using the sorption method

Unlike oxidizers, sorbents do not change, but remove water contaminants, so their use from a sanitary point of view is much more reliable. There is information in the literature about various types of sorbents: active carbons, clays, slags, etc. The effectiveness of using sorbents depends on their nature, specific surface area, the ratio of micro- and macropores and other factors, and therefore the adsorption capacity of the sorbent is different. Such sorbents, such as ash, slag, coke, brown coal, have a low sorption capacity in relation to the types of contaminants discussed earlier. But due to their low cost, they still find application (mainly in wastewater treatment). The use of these sorbents for the preparation of drinking water is unacceptable due to the release of undesirable substances from purified water.

Research on the use of natural sorbents (various clays) for water purification was carried out at the Moskvodokanalproekt. We tested montmorillonite clays (gumbrine, ascanite, askaegel), which were added to water in the form of suspensions. In addition, natural sorbents (pyrolusite, etc.) were studied as filter media. It was found that the sorption of a number of microelements occurs on these materials.

Compared to natural sorbents, activated carbons have a significantly higher adsorption capacity for most various chemicals, especially organic ones, which are becoming increasingly used in water purification technology both abroad and in our country. They are used mainly to deodorize water and improve its taste.

As is known, activated carbons are capable of sorbing phenol, and this substance is even accepted as one of the reference substances when evaluating various grades of coal. The effectiveness of using active carbons for removing certain types of pesticides from water is evidenced by the results of numerous studies. M.A. Shevchenko and his colleagues point out that activated carbons well adsorb hydrophobic substances, which include most organochlorine pesticides. The same authors point to the good effect of removing organophosphorus pesticides such as phosphomide, karbofos, chlorophos, and dichlorophos from water.

Activated carbons also have a fairly high sorption capacity in relation to surfactants.

In water supply practice, active carbons are used both in the form of powder dissolved in water and in granular form as a filter feed.

Carbonation of water has a number of disadvantages:

1). Powdered coal (as well as oxidizing agents) requires constant selection of its dose in accordance with the type and concentration of contaminants. This is relatively easy to do when removing tastes and odors from water, but when removing chemical contaminants, difficulties arise due to the complexity and time required of water analysis. At the same time, filters with granular carbon are a permanent barrier to sorbed contaminants (if the carbon capacity is not exhausted);

2) powdered coal is dusty, and this causes great difficulties in its use.

3) activated carbons are very expensive reagents, so it is advisable to use them repeatedly, using regeneration, which is much easier to implement when using granular carbons and is extremely difficult when carbonizing water.

Charcoalization of water. For the most complete use of the adsorption properties of powdered carbon, it is necessary to ensure a certain time of its contact with the treated water. Depending on the quality of the water, the required dose of coal and other factors, powdered coal is introduced at various points in the technological scheme of water purification: into water pipelines of the 1st rise, before settling tanks or clarifiers with suspended sediment, before filtering facilities. Since powdered coal is an additional load, its introduction in front of filter structures is possible only in relatively small doses.

Water purification methods

There are several methods of water purification, but all of them are included in three groups of methods:

— mechanical methods;

— physical and chemical methods;

— biological methods.

The cheapest - mechanical cleaning - is used to separate suspended matter. Basic methods: straining, settling and filtering. They are used as preliminary stages.

Chemical treatment is used to separate soluble inorganic impurities from wastewater.

When treating wastewater with reagents, it is neutralized, dissolved compounds are released, and the wastewater is discolored and disinfected.

What methods of water purification exist?

Physico-chemical treatment is used to purify wastewater from coarse and fine particles, colloidal impurities, and dissolved compounds. A highly productive and at the same time expensive cleaning method.

Biological methods are used to remove dissolved organic compounds. The method is based on the ability of microorganisms to decompose dissolved organic compounds.

Currently, of the total amount of wastewater, 68% of all wastewater is subjected to mechanical treatment, 3% to physical-chemical treatment, and 29% to biological treatment. In the future, it is planned to increase the share of biological treatment to 80%, which will improve the quality of the treated water.

The main method of improving the quality of purification of harmful emissions by enterprises in a market economy is a system of fines, as well as a system of fees for the use of treatment facilities.

The main task of water purification is to completely free it from suspended matter (turbidity), make it transparent (lighten) and reduce color to an imperceptible level. In modern conditions, the preliminary removal of zooplankton (the smallest animal organisms) and phytoplankton (the smallest plant organisms) from the water is of great importance. For this purpose, microfilters and drum screens are used, through which the water is filtered.

For clarification and decolorization, the complex of water treatment facilities includes: settling tanks, mixers, reaction chambers, filters, etc.

Septic tanks(horizontal, vertical) - structures designed for sedimentation under gravity of mainly large particles in size and mass suspended in water.

Horizontal settling tank diagram

The disadvantage of natural sedimentation of suspended matter in settling tanks is the duration of this process, which does not ensure the sedimentation of the main part of the fine suspended matter and all colloidal particles.

In order to accelerate and increase the efficiency of precipitation of suspended solids and removal of colloidal substances in settling tanks, water is coagulated before settling.

Scheme of a vertical settling tank:

1 - water supply;

2 - water drainage;

3—sediment discharge;

4 - flocculation chamber;

5 — ring collection tray;

6 - reflective cone.

Coagulation It is customary to call the process of enlargement, aggregation of colloidal and finely dispersed impurities of water, which occurs as a result of mutual adhesion under the influence of molecular attraction forces.

The coagulation process ends with the formation of aggregates visible to the naked eye - flakes.

Coagulation occurs under the influence of chemical reagents - coagulants, which include aluminum salts (aluminum sulfate A12(SO4)3) and iron (iron sulfate, iron chloride). To speed up the coagulation process, flocculant substances are used.

Filtration- this is the next process after coagulation and settling to free water from suspended substances remaining after the first stages of purification.

The essence of filtration is to pass water through a finely porous material, on the surface, in the upper layer or in the thickness of which suspended particles are retained.

The filter is a reinforced concrete tank filled with filter material, usually in two layers.

Quartz sand, anthracite chips, expanded clay (crushed and uncrushed), some volcanic slag, expanded polystyrene and others are used as filter materials.

There are two methods of filtering water.

Film filtration involves the formation of a biological film from previously retained impurities in the upper layer of the filter media. Initially, due to the mechanical sedimentation of suspended particles and their adhesion to the surface of the loading material (for example, sand), the pore size decreases.

The film reaches a thickness of 0.5-1 mm or more. It plays a decisive role in the operation of slow filters, retains the smallest suspended matter, 95-99% of bacteria, provides a reduction of oxidation by 20-45% and color by 20%.

2. Volumetric filtration is carried out on rapid filters and is a physical and chemical process in which mechanical impurities of water penetrate into the thickness of the filter media and are adsorbed on the surface of its particles and coagulant flakes. As a result of a decrease in pore size, the load resistance during filtration and pressure loss increase.

During the volumetric filtration process, about 95% of bacteria are retained. Rapid filters, allowing larger amounts of water to pass through, quickly become clogged and require cleaning more often.

Double layer filter

To purify waters with low turbidity and a high content of organic compounds, which are difficult to process in settling tanks and clarifiers, flotation is an effective purification method.

Flotation- this is a process, the essence of which is essentially that colloidal and dispersed impurities are combined with air bubbles finely dispersed in water.

The complexes that are formed float to the surface and form foam on the surface of the flotation device. A decrease in surface tension at the water-air interface leads to an increase in the efficiency of water purification by flotation.

Purifying drinking water: which purification method to choose?

To do this, surfactants (flotation reagents) are added to the water.

In the case of organizing a centralized supply of drinking water to small objects (villages, boarding houses, holiday homes, etc.), when using surface reservoirs as a source of water supply, compact structures of small capacity can be used for water purification.

They include: a tubular settling tank, a filter with granular loading, equipment for preparing and dosing reagents and a tank for rinsing water.

At modern water treatment plants, in the case of using reagent technological schemes, the introduction of chemical reagents into the treated water is carried out by automatic dosing systems.

These include reagent reservoirs, dosing pumps with microprocessor controls and injection valves.

Chemical dosing pump with microprocessor controller and injection valve

From this article you will learn:

• What methods of water purification exist?
• How different water purification methods work
• What is the most effective cleaning method?
• How to purify water at home
• How to purify water while traveling

Water pollution is a global environmental problem. Humans vitally need clean water, and modern science does not stand still in this regard. Scientists from all countries are working to solve this problem and are developing new systems and methods for water purification. The use of a particular method depends on the quantity, chemical composition and level of contamination of the liquid. In industry, certain technologies are used to restore standard water parameters, while in domestic conditions, completely different ones are used.

What methods of water purification exist?

There are various groups of methods for artificially improving water quality, regardless of the type of pollution and the nature of the impurities. Among them:

• biological;
• physical;
• chemical;
• physico-chemical.

To achieve maximum results, an integrated approach is most often used - combining the most effective methods and systems for water purification.

Biological methods of water purification

Biological methods for restoring standard water parameters are the most modern and quite effective. Biotechnologies are based on the use of living organisms - various types of bacteria, lower fungi, algae, protozoa and even some multicellular organisms (red worms and bloodworms).

The biological method of water purification is carried out by selecting a certain type of living organisms suitable for normalizing the chemical composition of wastewater. For example, nitrifying bacteria Nitrobacter and Nitrosomonas are used to oxidize nitrogen-containing compounds, and phosphate-accumulating organisms are needed to remove phosphorus from liquids.

Accumulations of colonies of bacteria and microorganisms that purify water runoff are called activated sludge. This dark brown or black silty mass with the smell of damp earth forms settling flakes when it settles. Colonies of microorganisms (zoogleys), depending on the conditions of biotreatment and the chemical composition of the liquid, can take different shapes (spherical, tree-shaped, etc.) After improving the quality indicators of wastewater, activated sludge with the zoogleys contained in it is easily separated from the water component.

The use of certain equipment and technological features of the cleaning process directly depend on the type of microorganisms that form the cleaning biomass. All of them are divided into two main groups: aerobic and anaerobic. Aerobic bacteria need oxygen to oxidize substances, which they consume during nutrition. Anaerobic organisms do not require oxygen to perform their “work”.

Conditions in which biological methods of water purification are used:

• biological ponds – natural or artificial reservoirs;
• filtration fields - areas of soil through which water is filtered (sand, clay, loam or peat);
• biofilters – special treatment facilities;
• aeration tanks (oxytanks) – complex structures for artificial aeration;
• Digesters are geometric reservoirs for anaerobic stabilization of sediments and wastewater.

Activated sludge microorganisms live in the soil of biological ponds, and natural aeration occurs. Microorganisms also live in sandy, clayey, loamy and peat soils, and filtration is carried out through them. Treatment systems of this type are simple and have no operating costs, but they are not able to deal with severe pollution.

A biofilter uses a layer of feed material for water purification, covered with a biofilm - a layer of aerobic bacteria. These microorganisms require oxygen to oxidize and biodegrade harmful substances. To ensure access to atmospheric air, an air distribution system is provided in the biofilter or natural aeration is used.

An aeration tank is a complex treatment facility for artificial aeration. During the biological treatment process, water is mixed with activated sludge, which contains colonies of aerobic microorganisms. Artificial aeration in the aeration tank helps saturate the environment with oxygen. The biodegradation processes of contaminants are stimulated by oxygen and additional mixing. Atmospheric air enters the aeration tank for aeration, and technical oxygen is used in the oxygen tank, which increases the efficiency of the cleaning process.

In digesters, wastewater is purified by anaerobic microorganisms. This method differs from the technologies described above in that oxygen is not required during the cleaning process. It is not water that is supplied to the reservoir, but concentrated sediment that falls in settling tanks. It undergoes intensive fermentation: mesophilic at a temperature of +30...+35 °C or thermophilic at a temperature of +50...+55 °C. To speed up the fermentation process, additional heating can be installed in the digester. Anaerobic decomposition occurs in several stages. The latter produces methane, which is an environmentally friendly fuel.

Physical methods of water purification

Physical methods of water purification have become widespread. They are mainly used at the initial stage of restoring the quality of the liquid and are called rough cleaning. Large solid inclusions are removed from the water mechanically, this can significantly reduce the load at subsequent technological stages.

There are other physical methods that allow for better deep purification of liquids, but due to low productivity, the efficiency of their use is reduced.

The most common physical methods for purifying water from iron and metals:

• straining;
• settling;
• filtration (including centrifugal);
• ultraviolet treatment.

Straining refers to methods of coarse purification and is mainly used at the preliminary stage of improving water quality. The liquid is passed through various screens and sieves, which retain solid and easily separated inclusions of metal contaminants. Straining allows you to reduce the load on fine cleaning installations and extend the service life of the equipment used.

Advocacy water as a purification method can be used not only at the preliminary stage, but also as an intermediate technological process. Water enters the tank for a certain period of time. Contaminants, under the influence of gravitational forces, are separated from the liquid and settle to the bottom of the tank, equipped with devices for removing the resulting sediment.

Filtration the technology for removing contaminants is very similar to filtering. The only difference is that this method can be used to carry out not only coarse, but also fine cleaning. The liquid to be purified is passed through a filter - a layer of porous material. Water passes through it freely, and small particles of contaminants (silt, sand, scale, microscopic solid inclusions) are retained in the pores of the filter material.

Filtration allows you to purify water from impurities and improve its organoleptic properties: color, taste, smell, transparency. The filtration method is not only widely used as an industrial method of water purification, but is also used to normalize liquid parameters in domestic conditions.

Ultraviolet disinfection does not apply to the direct purification of liquids, but is actively used as an additional cleaning stage of disinfection. Water that has undergone deep purification is treated with ultraviolet rays, invisible to the human eye. The range of light wavelengths is from 200 to 400 nm.

As a result of the photochemical reaction, the structure of the DNA and RNA molecules of living microorganisms is damaged, and the microbes die. The disinfection process does not depend on the composition of the liquid and does not change its structure. But when treating water with UV rays, it should be taken into account that solid impurities present in it can cause a shielding effect.

Chemical methods of water purification

Chemical water purification is based on the interaction of reagents with various types of pollutants. As a result of a chemical reaction, harmful substances decompose into safe components or change their state - contaminants turn into insoluble compounds and precipitate.

Based on the type of chemical interaction, three main methods of chemical water purification can be distinguished:

• neutralization;
• oxidation;
• recovery.

Neutralization is based on the interaction of acids and alkalis. As a result of the chemical reaction, the acid-base balance is equalized.

Neutralization is carried out in two ways. In the first case, the liquid to be purified is mixed with an acidic or alkaline medium, and in the second, reagents are added to the water, which cause a neutralization reaction.

Neutralization of acidic waste is carried out using ammonia water (NH 4 OH), soda ash (Na 2 CO 3), sodium and potassium hydroxide (NaOH and KOH), lime milk (Ca(OH) 2). To neutralize alkaline contaminants, acid solutions or acidic exhaust gases containing oxides CO 2, SO 2, NO 2 are used. The gases are passed through a contaminated water stream.

Oxidation And recovery- This is another method of water purification, which is characterized by the use of stronger oxidizing and reducing agents. The fact is that some pollutants do not react during the cleaning process using the neutralization method, then the toxic components are neutralized using strong chlorine-containing oxidizers: chlorine gas (CL 2), chlorine compounds, chlorine dioxide (CLO 2), potassium hypochlorite (KCLO) , sodium hypochlorite (NaCLO), calcium hypochlorite (Ca(CLO) 2).

In addition to chlorous acids, hydrogen peroxide (H 2 O 2), potassium dichromate (K 2 Cr 2 O 7), potassium permanganate (KMnO 4), air oxygen (O 2), ozone (O 3) are used for cleaning. As a result of the oxidation reaction, toxic and difficult-to-extract substances are neutralized - they are transformed into non-toxic or less toxic forms. Under the influence of strong oxidizing agents, the cellular structures of microorganisms are oxidized, and the microbes die.

Treatment of water with chlorine-containing compounds (chlorination) is a widely used method of purifying tap water. This method has many advantages. Available and inexpensive chlorine-containing reagents purify and disinfect water well and have a long-lasting antibacterial effect. In conditions of a worn-out water supply system, there is a risk of secondary pollution. Chlorine treatment is not only a reliable way to purify drinking water, but also a safe method of disinfecting water supplies.

At the same time, chlorination, like any other cleaning method, has its drawbacks, which prompt the search for alternative solutions. Some chlorine-containing reagents may contribute to the formation of toxic by-products. When using this method of purifying drinking water, we must not forget that chlorine is a toxic chemical element, therefore it is necessary to strictly observe the dosage of the chlorine-containing reagent and the chlorination technology.

Recently, ozonation - treatment of liquid with ozone - has become increasingly used to purify drinking water. This method is significantly more effective than chlorination. Ozone is non-toxic and absolutely safe for humans and animals, does not form dangerous compounds, and during the cleaning process it breaks down into diatomic oxygen (O 2).

Unlike chlorine, an overdose of ozone does not lead to dangerous consequences. Today, ozonation is one of the best ways to purify water. But its wide distribution is not yet possible due to the difficulty of obtaining ozone in large quantities and the need for increased safety measures at treatment plants due to the explosiveness of the gas.

Physico-chemical methods of water purification

Physico-chemical methods and methods of water purification are quite diverse and form a fairly large group. Exposure to pollutants and toxic substances is carried out using a combination of physical methods and chemical reagents. This allows you to better clean the liquid from dissolved gases and toxins, fine solid and liquid particles. This is an excellent way to purify water from manganese and other heavy metals.

The physico-chemical method can be used at any stage of removing harmful substances. It is equally well suited for preliminary normalization of liquid composition and for deep cleaning.

As mentioned above, this group of methods is quite extensive, so we will consider only the most common or basic methods of water purification by physical and chemical means:

• flotation;
• sorption;
• extraction;
• ion exchange;
• electrodialysis;
• reverse osmosis;
• thermal methods.

Flotation is a process of separating hydrophobic (water-repellent) particles, which is carried out through modern flotation units. A large number of ordinary air bubbles are passed through the water. As a result of flotation, suspended contaminant particles adhere to air bubbles, float to the surface of the flotation cell and become fixed, forming a layer of foam that is easily removed by the foam raking mechanism.

If the size of the separated particle is larger than the air bubble, then together they (particle and bubbles) form a flotation complex - flakes that float to the surface. In the physicochemical method of water purification, flotation is combined with the use of chemical reagents that are sorbed on particles of a toxic substance, reducing its wettability or increasing the coagulation of particles.

Coagulation is the combination and enlargement of small dispersed particles of pollution. Flotation is an effective way to purify water from petroleum products, oils and some solid impurities that cannot be removed by other methods.

To effectively purify natural waters, various types of flotation are used:

• foam;
• pressure;
• mechanical:
• pneumatic;
• electric;
• chemical, etc.

To better understand the principle of improving water quality, let's take a closer look at the two most common types of flotation - pneumatic (pressure) and electroflotation.

In pneumatic flotation, the aerator is located at the bottom of the tank. It consists of a perforated pipe and a plate. The air, which is supplied under pressure, passes through the holes in the perforated pipe, is crushed into many individual bubbles and creates an upward bubble flow. In the process of pneumatic flotation, the stream of liquid being purified is mixed with a stream intensely saturated with air bubbles. The mixed stream is fed under pressure into the flotation chamber, where the pressure drops sharply and the gas (air) dissolved in the water is released in the form of small bubbles.

In the process of electroflotation, water purification occurs on the surface of insoluble electrodes with a flotation effect. The electrodes through which electric current flows are located in a reservoir with purified water. Air bubbles form on the surface of these electrodes.

Sorptive Water purification methods are among the most effective technologies and can eliminate even the most minor contaminants in large volumes of water. Sorption methods are suitable for deep purification of water for various purposes, as well as for water treatment or post-treatment at the last stage.

During the process of adsorption (toxins are in the upper layer of the sorbent) or absorption (contaminants are distributed throughout the entire volume), selective absorption of harmful substances occurs. For high-quality deep water purification, not only physical, but also chemical methods are used.

During physical purification, adsorbed toxins are retained using molecular interaction forces - physical adsorption. With chemical - contaminants are eliminated through the formation of chemical bonds - chemical adsorption or chemisorption. The sorption method can remove herbicides, pesticides, phenols, surfactants, etc.

Activated carbons, silica gels, aluminum gels, and zeolites are used as sorbents. Their porous structure makes it possible to increase the specific area of ​​the adsorbent. This increases the efficiency and quality of cleaning. The adsorption process itself is carried out in two ways. In the first case, the contaminated liquid is mixed with a layer of sorbent. In the second, water is filtered through a sorption layer.

The type of sorbent and the pollutant being removed determines which technology will be used. In a regenerative cleaning process, the adsorbent is reused. If it is not subject to regeneration, then such a cleansing process is called destructive.

Extraction- This is another common method of water purification. Toxic substances are extracted from a liquid using extractants - an immiscible or difficult to mix liquid with water that dissolves a certain type of contaminant. During the extraction process, the liquid to be purified is actively mixed with the extractant. This provides a large phase contact surface. When stirring, the pollutant particles move into the extractant, after which the two phases are again separated into extract (extractant saturated with pollutant particles) and raffinate (purified water).

At the last technological stage, the extractant is extracted and disposed of or regenerated. This method is well suited for removing organic acids and phenols. Another advantage of the extraction method is that the extracted substances can be reused if they are of any value. In this case, the extractant is regenerated, and the extracted components are not disposed of, but are stored for other purposes.

The extraction method is widely used by industrial enterprises to purify wastewater and extract substances from it that are suitable for reuse in production.

Ion exchange- This is a very common method in industry and in everyday life for purifying water from salt. It is often used in the water treatment process to remove hardness salts and improve the quality of the liquid.

During the purification process, ions are exchanged between water and ion exchangers - solid high-molecular substances insoluble in water. These substances consist of a matrix (framework) with a large number of functional groups that have the ability to ion exchange.

Ion exchangers are divided into two groups – cation exchangers and anion exchangers. Their choice depends on the type of ions being exchanged. There are artificial ion exchange resins and natural ion exchangers: zeolites and sulfonated carbons. Currently, the use of natural ion exchangers has faded into the background. To improve the standard parameters of water and soften it, synthetic organic resins are used. Artificial resins are superior to natural ion exchangers in terms of ion exchange ability.

Household ion exchange filters are not designed to purify heavily polluted water, but the resource of one device is enough for a large volume of water. After use, the household ion exchange filter must be disposed of. Industrial filters are capable of deeper cleaning, and their ion exchangers are regenerated using special solutions intensively saturated with H + or OH - ions.

Electrodialysis refers to complex methods and combines membrane and electric water purification methods. Using electrodialysis, desalting is carried out and various ions are removed. The electrodialysis unit is called an electrodialyzer. The apparatus consists of several chambers separated by alternating cation-exchange and anion-exchange membranes.

The contaminated water flow enters the chambers. In the outer chambers there are electrodes to which direct current is supplied. Under the influence of an electric field, ions begin to move towards the electrodes according to their charge until they encounter an ion-selective membrane with the same charge. In the desalting chambers there is a constant outflow of ions, and in the concentration chambers the ions accumulate. As a result, two types of solutions are obtained from different chambers - concentrated and desalted.

Electrodialysis differs from the conventional membrane method in that the complex method for water purification uses special ion-selective membranes that allow ions of a certain sign to pass through. The main advantage of electrodialysis is that this method allows one to obtain concentrated solutions of separated substances from wastewater and use them for recycling. Therefore, this method of water purification is widely used in chemical plants.

The use of electrodialysis makes it possible to reduce the costs of chemical enterprises and preserve valuable components for recycling.

Reverse osmosis also applies to membrane methods of water purification. The entire process takes place under pressure above osmotic.

Osmotic pressure is an excess hydrostatic pressure applied to a solution separated by a semipermeable partition (membrane) from a pure solvent, at which diffusion of the pure solvent through the membrane into the solution stops. If the operating pressure is higher than the osmotic pressure, then the reverse transition of the solvent from the solution occurs. As a result, the concentration of the dissolved substance increases.

Using reverse osmosis units, it is possible to separate dissolved gases, colloidal particles, salts (including hardness salts), and various microorganisms (bacteria and viruses). This method is used to desalinate sea water, purify wastewater, and perform water treatment.

Thermal methods Water purification is based on removing contaminants using high or low temperatures. For example, evaporation is a fairly energy-intensive process, but this method allows you to obtain very pure water and a solution with a high concentration of non-volatile impurities. The same effect is achieved by freezing. Pure water crystallizes first, and impurities precipitate and form a saturated solution.

Using evaporation and freezing, contaminants can be separated, thereby improving the quality of the liquid. Thermal oxidation is used to neutralize very toxic substances and difficult to decompose contaminants. The purified water is sprayed and exposed to high-temperature fuel combustion products.

Methods for purifying water at home

In the modern world, it is not difficult to buy a reliable household filter for purifying liquids from impurities, contaminants and microorganisms (viruses and bacteria). Specialized stores offer a wide range of all kinds of devices: faucet attachments, filter jugs, pre-purification units, filters installed on the water tap.

But if for some reason there is no filter in the house or it has become unusable, do not despair. To quickly solve the problem, you need to know what methods and methods of water purification exist and how they can be used at home.

Advocacy is the simplest way to purify water. To disinfect and neutralize toxic substances and microorganisms, tap water is chlorinated. But chlorinated liquid has an unpleasant odor and taste. In addition, chlorine can accumulate in the human body, and during heat treatment (boiling) it forms harmful chemical compounds.

To neutralize the harmful effects of chlorine, you can use the method of settling water. To do this, fill a large clean container (for example, a bucket) with tap water and leave for 7-8 hours. This time is enough for not only chlorine compounds to evaporate, but also heavy metal impurities. Important! Only three-quarters of the settled water should be used for drinking and cooking. The remainder should be discarded.

Melt water- a simple home method of water purification. If you have a spacious freezer at home, then you can use this method. Take empty plastic bottles, fill them with cold tap water and place them in the freezer. When the contents of the bottles are half frozen, you will see that unfrozen water remains in the middle of the volume - this is a solution of impurities and contaminants that should be poured out. Melt the remaining ice and use it for drinking and cooking.

Lack of transparency, a gray or yellow tint, or turbidity indicates that the ice is not pure enough. This liquid contains harmful contaminants and should not be drunk. Pure melt water is very beneficial for the skin. Cosmetologists recommend using it for washing.

This method can be called a natural way to purify water. In nature, a pure liquid always freezes first, and all impurities, contaminants and salts remain in solution. For example, even on the surface of a sea body of water there is a layer of frozen fresh water.

Silicon enrichment. Silicon is called a natural filter, as it has fairly strong bactericidal and anti-inflammatory properties and cleans and disinfects water well. You can buy it at a pharmacy or order it in an online store at a very affordable price - 230–250 rubles for 150 g. Drinking water enriched with silicon improves metabolism, helps eliminate carcinogens, toxins and waste from the body, and is good for the gastrointestinal tract . Enriching liquids with silicon can be called a popular method of water purification. This method is often used for therapeutic and prophylactic purposes.

If you decide to use silicon as a filter, then before the first use, rinse it thoroughly, then fill it with regular tap water and leave it immersed in the liquid for 2-3 days. After this time, you can drink purified water in small sips, 2-3 glasses per day. At least once a week, silicon crystals should be thoroughly washed to remove plaque formed during the cleaning process.

Activated carbon cleansing. Activated carbon has a high sorption capacity and is an effective liquid purifier. This sorbent is necessarily included in bulk filters for household use. Activated carbon absorbs all toxins and improves the taste and smell of tap water. This method is also suitable for purifying water from wells.

At home, you can make a filter for water purification with your own hands. To do this, sew a bag of thin fabric or gauze and fill it with granules or activated carbon powder. If the coal is in tablets, then they must be crushed. Place the prepared filter on a container and direct a stream of water at it. The only drawback of this cleaning method is that after a few days you will need to replace the homemade filter.

Cleansing with silver. The method of purifying water with silver has been known since ancient times. Silver ions have a bactericidal effect, clean and disinfect liquids well. To improve the quality of drinking liquid, pour it into a glass container, place pure 999 silver items inside and leave them in the container for 8-10 hours. This cleaning method has some contraindications. Constant consumption of such water can lead to the accumulation of silver in the human body. And since this metal is heavy, its excess can cause metabolic disorders.

How to purify water while camping

On any long hike, the question always arises about what methods of water purification can be used in natural conditions. This is especially important if the sources of life-giving moisture are in doubt, and it is not possible to stock up on drinking water. In this case, for drinking and cooking, you have to take liquid from any body of water that comes along the way, and this is very dangerous for health. To protect themselves, every tourist should know the most accessible and effective methods of purifying water in nature:

Filtration.To quickly filter liquid, you can use ordinary sand. Take a bottle or funnel, put a piece of cloth or thick paper in it, and pour a layer of sand on top. If you don't have any nearby, use crushed charcoal from hardwood trees. Once the filtration device is made, run water through it.

If you don't have a bottle or funnel at hand, you can use a cap as a filter. Fold it into a funnel, place it over a clean container and pour water through it. For best results, it is recommended to pass the water through the filter several times until it becomes clear. To make things easier, purchase a portable filter before heading out on a hike.

Distillation and distillation. In some bodies of water, the water is so polluted that it cannot be purified by filtration. In such cases, experienced tourists use distillation and distillation. Make the simplest desalination device and place it with both ends pointing up. Pour water from the reservoir into the pipe (desalinator), and place two pans, bottom up, over the open ends of the pipe.

Attach a clean cloth folded in several layers to the inside bottom of each pan. Light a fire under the chimney. Steam from the pipe will enter the pans and condense on the fabric. Once the cleaning process is complete, take a clean container and squeeze the liquid out of the cloth into it.

If it is not possible to find a metal pipe, there is another way to purify water using distillation. Place any fireproof container with a narrow neck on the fire. Take a tube and insert one end into a fireproof container and the other into a container to collect water. To prevent the liquid from evaporating along with the steam, tightly seal or cover the neck of the dish standing on the fire with clay; steam will only escape through the tube.

In cold conditions, you can freeze water for cleaning. Pour the liquid into a wide bowl and wait until the top layer is two-thirds frozen. Carefully remove the ice from the container and drain the unfrozen residue.

Filtration purifies the liquid only from solid contaminants. After filtering, the water must be disinfected. To destroy harmful microorganisms, you can use simple methods of purifying water from metals and impurities: boiling, using chemicals, disinfecting with bactericidal plants.

Boiling. Place the pot or pan on the fire, bring the liquid to a boil and simmer for about 10 minutes. In case of heavy contamination, the boiling time should be increased to 30 minutes.

Chemical method. For a liter of water, take 2 teaspoons of regular table salt. Dissolve it well in the liquid and leave to infuse for 30 minutes. Microorganisms will die in the saline solution. The only drawback of this cleaning method is the salty taste of the water.

An effective method is to disinfect water with bleach. First make a stock solution. To do this, dissolve half a teaspoon of bleach in a liter of water. To disinfect water, add 1 teaspoon of mother solution to 1 liter of water, shake the container well and leave to settle. Purified water must be filtered before use.

Our grandmothers also used potassium permanganate to disinfect water. Take 1 liter of water, drop two crystals of potassium permanganate into the liquid and stir well. The solution will turn out to be pale pink.

You can also use disinfection tablets to purify water, which are sold in specialized tourist goods stores.

Natural remedies. Since ancient times, people have used plants that have a bactericidal effect. To purify water in the forest, take pine, juniper, fir needles, or separate the bark from the trunk of a deciduous tree. Willow, oak, and birch are suitable for this. Boil water with pine needles or pieces of bark for about 40 minutes and leave to steep for at least 6 hours.

If the water quality leaves much to be desired...

The problem of dirty water in the house can be partially solved by installing a high-quality filter, but in such systems it is periodically necessary to replace components, because this directly determines how well the drinking liquid will be purified.

At the same time, the question remains unresolved: how to ensure that our workplace or child’s school has the best quality water? The best solution is to buy it with delivery.

The Iceberg company offers favorable conditions for servicing its clients:

• free delivery of water to your home or office: buyers pay only the cost of the product;
• the wells from which our water is drawn have registration documents in the State Water Cadastre of the Russian Federation;
• Advanced technologies are used to extract and bottle water, which helps preserve and enhance its quality and natural purity;
• We also sell modern water coolers and other equipment manufactured by well-known European brands, taking into account existing quality standards. The sizes of pumps and racks for bottles vary, allowing the devices to be installed even in small spaces;
• delivery of drinking water to your home or office is carried out at a minimal price, thanks to constant promotions from our company;
• Along with water, you can purchase disposable tableware, tea, coffee and other auxiliary products.

Clean water is valuable, but it should not be worth its weight in gold. Our mission is to provide every home and workplace with high-quality drinking water, so we have prepared the most favorable conditions for our clients.

The text of the work is posted without images and formulas.
The full version of the work is available in the "Work Files" tab in PDF format

I Introduction

All living things in our lives are connected with water, so there is no more exciting and discussed topic than the topic of water. The quality of tap water is especially problematic. I proved this with my previous work. You can buy already purified water in the store, but bottled water costs money, and using it constantly is quite expensive. Taking care of your own health and the health of your family, you can find the best way to purify water at home, so I consider the topic “Methods for purifying tap water at home” relevant.

Target: experimentally identify the most effective method of water purification at home

Tasks:

Study literature and materials on the Internet about methods of water purification;

Conduct a survey among primary school students;

Determine experimentally the most effective and affordable methods of water purification at home;

Evaluate the results obtained and draw conclusions;

Based on the results of the work, create a booklet for students of your school and their parents;

Hypothesis: You can purify tap water yourself

Object of study: water.

Subject of study: tap water

Relevance: For the normal functioning of the body, water is needed that does not contain harmful impurities and mechanical additives, i.e. good quality.

Practical significance: materials and results of the work can be used at extracurricular activities, in club work, in lessons, as well as to inform students and their parents.

Research methods:

Working with an information source;

Social survey (questioning);

Drawing up analytical diagrams;

Researching;

Study of literature;

I decided to get information on this topic from primary school students and asked them the following questions:

Do you drink tap water?

What kind of water do you drink?

What cleaning methods do your family use?

We systematized the data obtained and presented it in pie charts.

Of the children I interviewed, the majority do not drink tap water, but drink filtered and boiled water. I was interested in what other methods of water purification exist.

From the “Ecological ABC for Children and Teenagers” I learned various methods of water purification. I conducted research to identify the most effective and affordable method of water purification.

II Main part

Water purification methods

Purification is the removal of foreign and unwanted substances from water. And also from harmful impurities.

During my research work, I studied different methods of purifying drinking water at home.

1.Filtration - the process of separating heterogeneous systems using porous partitions. Filtration of liquids in the laboratory is carried out using funnels into which special filter paper is inserted. . Some semblance of them was created in China and consisted of ordinary reeds impregnated with coagulants. One of these simplest filters even went down in history as the “Hippocratic sleeve.” Prototypes of modern filters. Their operating principle was close to natural purification processes and consisted in the passage of water through a layer of various substances: crushed stone, sand and charcoal.

2 Water purification using filters

To remove harmful impurities from tap water, various filters are used. At home, a variety of jugs and faucet attachments are often used. This is the most common and affordable method of water purification. Drinking filters - jugs are able to remove excess chlorine, organic substances, and scale (hardness salts) from water. Jug filters purify tap water quite effectively, are cheap to purchase initially, and are therefore widely used. All drinking filters - jugs are equipped with a replaceable cleaning element (also called a “cassette” or “cartridge”). The cassette is designed to maintain a constant flow rate of water through the cleaning mixture. The mixture includes activated carbon, polypropylene liner, and several types of ion exchange resins. This is important for uniform and complete water purification. This type of filtration is aimed directly at purifying the liquid from harmful impurities such as chlorine or pesticides. It can also rid water of various unpleasant odors and make the water absolutely transparent. This cartridge must be replaced approximately once every three months.

Activated carbon for water purification.

Activated carbon is a well-known water purifier and is used in a wide variety of filters. After treatment with coal, the water acquires a pleasant taste and smell, since coal absorbs almost all harmful substances found in tap water and also removes lime. But you can purify water yourself with coal.

Advocacy When water settles, chlorine and ammonia are removed from it, and some salts and colloidal solutions settle to the bottom. However, heavy metal salts will not go away from settled water; at best, they will settle to the bottom.

Freezing water

Today this is an increasingly popular method of water purification, which, moreover, is also considered effective. Melt water is very poor in salts. Therefore, the amount of beneficial minerals, especially potassium and sodium, must be replenished with other drinks or food. It is known that drinking melt water cleanses the blood and lymph, all internal organs and skin. At the same time, the functioning of the cardiovascular system improves and metabolic processes are activated. At the same time, an unprecedented influx of strength and energy is felt.

Purifying water with silver

Since ancient times, people have known a method of purifying drinking water using silver. Silver is an excellent bactericidal agent; it can kill various microbes. Silver also promotes long-term storage of water. Even in ancient times, people noticed that water from silver jugs was different from ordinary water. It does not go rotten for many months, and food cooked on it lasts much longer and tastes much better.

Water purification with silicon- the oldest method. Silicon is one of the main elements in Mendeleev's periodic table. Silicon got its name from the Greek word meaning “rock, cliff.” It is the second most common chemical element found on Earth. Clay, sand, opal, jasper are all varieties of silica, which contains the most silicon. With the help of silicon, even water is purified, which acquires absolutely amazing qualities and has a beneficial effect on the human body.

Cleaning with shungite.

Shungite is the oldest carbon-containing mineral on the planet. This stone is mined in Karelia. The amazing properties of shungite have been known in Russia for a very long time; they only called it “slate stone.” By order of Peter I, each of his soldiers was obliged to carry a “slate stone” with him in his marching backpack, so that by dropping these stone pieces into a pot of water, he would obtain disinfected water.

Shungite purifies water from organochlorine compounds, excess copper, manganese, iron, nitrates and nitrites, completely from helminth eggs, removes turbidity, tastes, odors from water, and completely disinfects water.

At the same time, it can saturate water with various macro- and microelements to a concentration that is optimal for the human body.

Water purification using mountain quartz.

The simplest, most common and familiar example of quartz is sand. In its pure form, quartz is colorless or white. Quartz does not dissolve in water.

The method of infusing water on quartz came from distant Tibet. It is over 3000 years old. This is the oldest, simplest and most effective method of water purification. Quartz purifies water from metal compounds, radionuclides, and various harmful impurities. Quartz water facilitates the transport of nutrients directly into cells and the removal of toxins from the body.

Folk remedies For water purification there are also: purification with a bunch of rowan, purification with willow bark, iodine, nettle, etc.

III The experiment consists of three stages

Stage 1- purifying water in different ways

Target: Show different ways to purify tap water

Equipment : tap water, water containers, two types of filters, activated carbon, kettle for boiling water, freezer, silver spoon, silicon, shungite, mountain quartz

Test 1. Filtration using a jug filter. (Appendix I)

I poured water filtered using a jug into a glass

Test 2. Filtering using the built-in filter. (Appendix I)

I poured water from the filter into a glass. I took readings using instruments.

Test 3. Activated carbon for water purification (Appendix I)

I wrapped activated carbon tablets, about five of them, in gauze and placed them in a container of water. I put it in a cool place and waited 10-12 hours. The water must be kept in a cool room, otherwise the coal will not only not neutralize the water, but, on the contrary, will promote the growth of bacteria.

Test 4. Boiling (Appendix II)

I poured water into the vessel and boiled it for at least 10-15 minutes. In this case, the process is accompanied by the release of steam.

Test 5. Advocacy (Appendix II)

To purify water using this method, I poured water into a container and left it for about 6-7 hours without covering it with a lid. For the first time in 3-4 hours, volatile impurities such as chlorine and ammonia will evaporate from the water, and in the next 2-3 hours, salts of heavy metals will settle. Then she carefully poured ¾ of the water into a clean container and poured out the rest...

Test 6. Freezing water (Appendix II)

In order to prepare melt water I needed:

Take a large bowl and pour water into it, not reaching the edges by about a centimeter;

I left this dish in the freezer for 4-5 hours. It is necessary that at least part of this water freezes;

When half of the water in the vessel froze, I broke the ice that had formed on top and drained the water from the bottom. Only ice can be drunk or used for cooking. And only its transparent parts. Harmful substances have accumulated in the remaining parts, making them unsuitable for drinking.

The method is designed to ensure that the clean part of the water in the vessel freezes first. And harmful substances, in turn, settle to the bottom of the dishes, which I successfully drain.

Test 7. Water purification using silver (Appendix III)

I filled a large container with water and placed a silver object at the bottom - a spoon. By morning, silver ions will purify the water no worse than any filter.

Test 8. Water purification with silicon (Appendix III)

Before first use, the flint must be washed. I placed the stones in a container and filled it with water. Covered it with gauze and put it in a dark place, away from sunlight, and let it sit for 3 days. After this, the water can be consumed. As consumption progresses, leave some of the water (at the level of the pebbles), add and leave for 8-10 hours, continuously for 6-8 months.

Test 9.Cleaning with shungite (Appendix III)

To purify water using shungite, I first washed the stones with running water. I filled the minerals with tap water at the rate of 150g. for 2-3 liters. I insisted for 3 days. As consumption progresses, add water and leave for 8-10 hours. Rinse shungite once a week. This water is suitable not only for drinking, but also for cooking, making tea and much more.

Test 10. Water purification using mountain quartz (Appendix IV)

I washed the quartz in cold running water, then filled them with water at the rate of 200 grams of stones per 3 liters of water. It is necessary to infuse the water for three days and use it in its pure form; as the water is consumed, you can add it to the container. Once a week, it is advisable to remove the stones and wash them to remove any deposits that have formed.

Stage 2 - water measurement TDS meter

The TDS meter is used to assess the quality of drinking water. It shows the amount of inorganic impurities suspended in water, mainly salts of various metals. Hence the second name - salinity meter. In everyday life it is used to determine the quality of tap water.

Target : experimentally demonstrate the presence of salts of various metals

Equipment : device TDS-meter, 10 samples of purified water

I poured a clean glass of purified water. Removed the protective cap from the device. Pressed the "ON" button to turn on the display. I immersed the device's sensor in water and waited about 10 seconds. I took readings from the display. I entered the results into a table and compared them with tap water.

Water purification methods	TDS is the amount of salts of various metals.
Filtration
Built-in filter
Activated carbon cleaning
Boiling
Silver cleaning
Advocacy
Freezing
Silicon cleaning
Shungite cleaning
Cleansing with rock quartz

Tap water indicators

Tap water

Conclusion : According to the readings of the TDS meter, the lowest salt content is in water purified with shungite.

Stage 3 - measuring water with an electrolyzer

The electrolyzer is designed to test water for the content of impurities and microelements. Using an electrolyzer, you can clearly see not only the presence of certain microelements, but also determine their quantity by the intensity of the color of the water. The more intense the color obtained during the experiment, the higher the concentration of substances in the water. The optimal color for clean and healthy water is from light yellow to orange. He talks about the presence of useful microelements in water, such as calcium, sodium, potassium, fluorine, etc. in the required concentration, an excess of these trace elements will color the water fiery red. Exceeding the permissible limit of harmful and dangerous microelements, such as cadmium, lead, arsenic, nickel, chromium, mercury, etc. colors water green, blue and black with different shades depending on the concentration of these substances.

Target: experimentally show the content of impurities in water

Equipment: electrolyzer device, 10 samples of purified water.

To conduct the experiment, I prepared two transparent water glasses with a capacity of 100-500 ml. I placed them on the table next to each other. I poured water. She placed the electrolyzer in a glass and then turned on the power. Pressed the "on" button and ran the test for 30 seconds, then turned off the device. So I tested the water I purified. The results were entered into a table and compared with tap water.

Water purification methods	Electrolyzer tests water for impurities and microelements.
Filtration	orange sediment
Built-in filter	orange sediment
Activated carbon cleaning	bright orange color
Boiling	orange sediment
Silver cleaning	slight sediment
Advocacy	orange residue
Freezing	slight sediment
Silicon cleaning	orange sediment
Shungite cleaning	orange sediment
Cleansing with rock quartz	orange sediment

Tap water indicators

Tap water

Black sediment

Conclusion: According to the measurement results, the least amount of salt content is in water purified with silver and in frozen water.

Conclusion.

During the research work, the hypothesis I put forward was confirmed. During the work, various methods of purifying tap water were studied and tested (filtering, boiling, settling, freezing, saturation with silicon ions, silver purification, etc.) Based on the experiments, I concluded that at home it is really possible to purify water at minimal cost. Evaluating various methods of water purification, we can draw the following conclusion: the most effective method is purification with silicon, shungite, quartz, filtered by a built-in filter. The most practical method turned out to be freezing and settling. In my work, I shared my personal experience of determining the quality of drinking water at home.

Bibliography

V.P. Sitnikov G.P. Shalaeva “Who is who in the natural world” Poligrafizdat, 2011 (p. 5-6)

A.E. Chizhevsky Children's encyclopedia “I explore the world: Ecology” 2001 (p. 118-119)

Ecological ABC for children and teenagers. Publishing house MNEPU Moscow 1995 (from 92)

Miklashevsky G.S. Pure water. Household filters. - St. Petersburg: Arlit, 2000.

The newest complete schoolchildren's reference book: grades 5-11: in 2 volumes: Biology; Chemistry; Geography. - M.: Eksmo, 2009. (494 pp.)

Encyclopedia for children. Ecology. Moscow Avanta 2001(324 pp.)

E. Mikheeva “Healing properties of silicon” S - P, 2002 (15 pp.)

Kibardin Gennady “Shungite: Natural Healer” Eksmo 2012 (38 p.)

Shubnikov A.V. “Quartz and its application” 2012 (9 pp.)

Tap water

Built-in filter

Boiling

Advocacy

Freezing

Cleansing with silver

Silicon purification

Shungite cleansing

Mountain quartz cleansing

The lives of both humans and all humanity. That is why modern science is constantly working to create new cleansing methods.

The methods primarily depend on the quantity and quality of the liquid being purified. For example, industry uses the same methods, but at home you can purify running water in a completely different way.

Industrial methods of water purification

Water taken from reservoirs or underground sources, before entering the water supply system, passes. These methods are also used in wastewater purification, which is an integral part of the operation of any industrial plant or factory.

1. Mechanical methods of water purification. The name of the method itself indicates exactly what purpose is being pursued here. Using a variety of filters, water is purified from unnecessary and harmful particles. To begin with, the liquid falls on the surface of the filter, from where it passes through the entire feed, thus trapping particles of a certain size. But if this method can be used to get rid of relatively large pollutants, filters cannot save bacteria and small organic particles.
2. Water chlorination. A fairly well-known purification method that allows you to disinfect water. But this technique also has its drawback, which every person knows about. It is simply impossible to drink such water.
3. Ozonation. A relatively new and quite effective method of water purification, which allows you to get rid of organic residues. Ozone is also considered a very strong disinfectant. Unfortunately, this method is quite expensive and is just beginning to gain popularity.

Unfortunately, the water supplied to houses and apartments is not always of high quality. That is why you need to think about how to make it better at home.

Methods at home

As a rule, there are some problems with water flowing from the tap. Firstly, it contains magnesium and calcium salts, which make it tough. Another danger is the presence of unnecessary organic breakdown products, including nitrites and ammonia. The water may also contain impurities of iron and manganese - this liquid becomes yellowish in color. Most often, rust deposits in water are the result of rust moving through old pipes. And, of course, one of the main problems is chlorine.

But water can be purified and made suitable for use on your own. There are several very effective and common methods.

1. Advocacy. In order for the water to become clean, it must be placed in a container and allowed to stand for at least a day. During this time, approximately 90% of the chlorine will disappear from the liquid. If a reddish sediment has formed at the bottom, the water must be filtered. But this method will not work if the liquid is saturated with bacteria and microscopic algae.
2. Boiling. This method allows you to significantly soften the water, since magnesium and calcium salts will simply settle on the walls of the dish. During boiling, all chlorine will disappear from the liquid. In addition, high temperatures will help destroy most living microorganisms. But if there is a high level of organic substances in the water, you cannot boil it, since nitrogen compounds will quickly react with chlorine.
3. Household filters for water purification. Today we are offered a huge selection of a wide variety of filters. The operation of passive filters is based on simple filtration, when some of the polluting particles simply settle in the pores. By the way, they are often used as a filling for such a filter.

There are also active filters containing a certain number of substances. These substances, when water passes through, react with pollutants, thus neutralizing them.

It is worth noting that the water filter must be chosen very carefully. First of all, be guided by the problem of your water, be it hardness or the presence of organic matter.

It's hard to imagine your life without water. We use water for drinking, cooking, personal hygiene, washing, etc., that is, water is necessary for normal human life. Therefore, it is so important that it is clean and absolutely harmless to health. Unfortunately, it is very difficult to find today. And there can be many reasons for this - from the unsatisfactory condition of water pipes to the characteristics of water supply sources. This is why the issue of water purification at home is so relevant today.

The main disadvantage of tap water is excessive hardness, that is, an excess of calcium and magnesium salts, bicarbonates, sulfates and iron. High hardness gives water a bitter taste, has a negative effect on the digestive system, disrupts the water-salt balance in the human body, forms limescale on dishes and heating elements of household appliances, and damages fabrics during washing.

Tap water may contain various impurities: nitrogen compounds, sodium salts, potassium, calcium, manganese, etc. Chlorination has controversial benefits. On the one hand, chlorination is an effective, accessible and inexpensive way to disinfect water.

On the other hand, chlorine significantly worsens the taste of water; in addition, chlorine, when reacting with organic compounds, can form chlorine-containing toxins, mutagenic and carcinogenic substances and poisons, including dioxides.
Naturally, the quality of tap water is monitored by the relevant authorities and if the concentration of harmful impurities in it is exceeded, appropriate measures are taken. However, most experts are unanimous in their opinion: you should not drink water directly from the tap. You need to at least boil it.

Advocacy

Sedimentation is the simplest way to purify tap water. By settling we mean the process of separation from water under the influence of gravitational forces of suspended particles, namely salts, some heavy metals, etc. To purify water using this method, you need to take a clean vessel, for example, a jar, fill it with tap water, cover it with a lid and leave for 5-6 hours. During this time, suspended particles will settle to the bottom. You can only use the upper 2/3 of the water; it is advisable to pour out the lower 1/3 of the water, since it is in it that all harmful impurities are concentrated. It is not recommended to stand water for more than the specified time, since pathogenic bacteria can begin to multiply in water that stands for a long time.

Boiling

Boiling is considered the simplest and most affordable way to purify household water. Moreover, if the water is not purified through filters, boiling is a prerequisite for its healthy consumption. Boiling helps clear water of many types of impurities. Under the influence of high temperature, most of the bacteria die, chlorine-containing compounds are destroyed, and the water becomes soft and tasty. However, boiling also has its disadvantages.

1. Firstly, in chlorinated water under the influence of high temperature, dioxide is formed, which tends to accumulate in the human body and has a carcinogenic effect.
2. Secondly, ordinary boiling (not long-term) does not destroy all microbes, not to mention heavy metals, nitrates, phenol and petroleum products.
3. Thirdly, with prolonged exposure to high temperatures, the structure of water is destroyed and, at best, it becomes not useful, and in the worst case, harmful to health. Boiled water is heavy or, as it is also called, “dead” water. It contains heavy isotopes of hydrogen - deuterium atoms. The negative impact of such water on the human body has been confirmed by numerous studies.

In order for water purification by boiling to be as effective as possible and negative effects to be minimal, it is important to follow the following rules:

• Do not boil the water again, pour out the remaining water from the kettle and rinse it after each use.
• It is advisable to boil pre-filtered water or at least settled water.
  Use only the top 2/3 of the volume for drinking or cooking, discard the remaining water
• If necessary, descale the kettle and other utensils
• Avoid prolonged boiling

Freezing

You can purify tap water at home by partially freezing it. The essence of this purification method is as follows: purer and fresher water freezes faster, then water containing impurities and salts crystallizes. To purify water using this method, you need to pour water into a container, for example, a plastic bottle, and place it in the freezer. When the first thin layer of ice forms on the surface of the water, it should be removed, as it is fast-freezing heavy water.

After the water freezes by about half, remove the container from the freezer. Frozen water should be used for drinking and cooking. Unfrozen water should not be used. In winter, it is much easier to purify water. In frosty weather, containers with water can be placed outdoors.

For the best effect, you can use double purification, that is, first let the water stand or pass it through a filter, and then freeze it.

By the way, since ancient times it has been known that melt water has a number of properties. Thus, purifying water by freezing allows you to obtain not only clean, but also healing water.

Bottled water

You can replace low-quality tap water with bottled water, which can be easily purchased at any store. Now many people prefer this kind of water, considering it as safe as possible for health. Bottled water is divided into two categories: first category water and premium water. Water of the first category is well-purified tap water. That is, tap water is first purified from impurities, then disinfected, after which useful elements are added to it and poured into containers. Such water is undoubtedly better than tap water, but not all manufacturers manage to completely purify the water from impurities.

The quality of water of the highest category is much higher. Most often this is clean underground water that does not contain harmful impurities. Such water is either initially rich in compounds such as fluorine, potassium, calcium, iodine, or it is enriched with them before pouring into containers. There is a misconception that it is enough to clean water from all impurities and it will be useful. In fact, water should enrich the human body with minerals. Unfortunately, there are many unscrupulous manufacturers on the market who sell not only poorly purified bottled water, but also insufficiently mineralized water. Therefore, in order not to purchase a fake, you should pay attention to the following points:

• The label of the water container must contain information about the category of water
• The container must not have dents, drawings and inscriptions on the label must be clearly printed
• There should be no sediment at the bottom of the water container
• It is better to buy water from well-known manufacturers who have been producing similar products for a long time

Household filters

Clean and healthy water can be obtained using household filters. There are many different filters that can be used to purify water to varying degrees of purity. Household filters are divided into two groups:

1. Jug filters. They are easy to use and affordable, however, their productivity and degree of water purification are low. If tap water contains many mechanical impurities, but its chemical composition meets the standards, you can limit yourself to this device. The filter has a long service life; the main thing is to replace the cartridge approximately once every 1.5-2 months (after cleaning 150-300 liters of water). The jug must be washed regularly, and filtered water should not be stored in it for a long time. Otherwise, it may be damaged. Before a long break in use, it should be washed, dried and stored in a dry place, since moisture is a favorable environment for the proliferation of pathogenic microbes.
2. Flow models. They are connected directly to the water supply or tap, are relatively expensive, but are characterized by high performance and provide high quality purified water. The use of such models is advisable if the water is highly hard and has harmful impurities. The cartridges used in them not only perform mechanical water purification, but also precipitate toxic chemical impurities and make the water softer and more palatable.

For the filter to work effectively, it is necessary to promptly change the cartridge, which has a limited resource. As a rule, in stationary models the cartridge lasts approximately 1 year. It is important to remember that flow filters require continuous operation. With a long break in the use of such a filter, optimal conditions for the proliferation of microbes are created in its cartridge, and the performance properties of the filter material are also lost. As a result, it may be necessary to replace the cartridge and thoroughly clean the filter cavity.

Activated carbon and mineral filtration

It is believed that activated carbon absorbs substances harmful to the human body from water, including heavy metals such as lead, radon and its decay products, chlorine, pesticides, etc. At the same time, it enriches the water with valuable minerals. To purify water, activated carbon tablets are packaged in a gauze bag and placed in a container with water for 12-14 hours. After this time, clean water is suitable for consumption. It is not recommended to leave water with activated carbon for a longer period, as such water can become a favorable environment for the proliferation of various microorganisms.

Minerals, in particular silicon, are often used to purify water.

This method of obtaining clean water was used in Ancient Rus'. It is believed that thanks to the activation of water by silicon, it becomes not only pure, but also more tasty and can be stored for a long time without changing its composition. In such water, the life of viruses and pathogenic microbes is simply impossible. Silicon absorbs substances harmful to human health, such as salts of heavy metals, pesticides, etc. To purify water with silicon at home, you need to place the silicon, washed under running water, in a glass or enamel container, add water at the rate of 10 g of mineral per liter of water. Cover the dishes with a clean cloth and place in a dark place for 2-3 days.

After the specified period, use the upper 2/3 of the water, pour out the remaining layer, since this is where harmful substances from the water accumulate. The resulting silicon water cannot be stored in the refrigerator or boiled. It is better to leave it stored indoors at a temperature not lower than +10 °C.

This video will tell you about modern methods of drinking water purification:

Tell your friends! Share this article with your friends on your favorite social network using social buttons. Thank you!

Telegram

Read along with this article:

• Lipetsk pump room is a mineral water endowed with healing…