Natural water, as a rule, does not correspond hygienic requirements requirements for drinking water, therefore, before supplying it to the population, it is almost always necessary to purify and disinfect it.

Natural water consumed by humans for drinking, as well as used in various industries, must be safe in sanitary and epidemiological terms, harmless in its chemical composition and have favorable organoleptic properties.

It is known that none of modern methods water treatment does not ensure its 100% purification from microorganisms. But even if the water treatment system could facilitate the absolute removal of all microorganisms from water, there is always a high probability of secondary contamination of purified water during its transportation through pipes, storage in containers, contact with atmospheric air, etc.

Sanitary rules and regulations (SanPiN) do not aim to bring water to microbiological indicators to ideal, and therefore sterile, quality, in which all microorganisms will be absent. The task is to remove the most dangerous of them for human health.

Currently, there are many known methods of water disinfection and many devices used for their implementation. The choice of disinfection method depends on many factors: source of water supply, biological features microorganisms, economic feasibility etc.

Water purification, including its decolorization and clarification, is the first stage in the preparation of drinking water, at which suspended substances, helminth eggs and a significant part of microorganisms are removed from it.

However, some pathogenic bacteria and viruses penetrate through wastewater treatment plants and are kept in filtered water. In order to create a reliable barrier to the possible transmission of intestinal infections and other equally dangerous diseases through water, disinfection is used, that is, the destruction of pathogenic microorganisms - bacteria and viruses.

It is microbiological contamination of water that leads to the maximum risk to human health. It has been proven that the danger of diseases from pathogens present in water is thousands of times higher than when water is polluted with chemical compounds of various natures.

In water treatment technology, there are many methods of water disinfection, which can be divided into two main classes - chemical and physical (or reagent-free), as well as their combination.

Chemical or reagent methods of water disinfection include the introduction of strong oxidizing agents, which include chlorine, chlorine dioxide, ozone, iodine, sodium and calcium hypochlorite, hydrogen peroxide, and potassium permanganate.

Of the above oxidants, practical application in water disinfection systems is found: chlorine, ozone, sodium hypochlorite, chlorine dioxide.

Another chemical method is oligodynamy - exposure of water to ions of noble metals.

Physical methods of disinfection:

Ultraviolet irradiation;

Thermal exposure;

Ultrasonic exposure;

Exposure to electric discharge.

The effectiveness of water disinfection by chemical and physical methods largely depends on the properties of water, as well as on the biological characteristics of microorganisms, i.e. their resistance to these influences.

The choice of method, assessment of the economic feasibility of using a particular method of water disinfection is determined by the source of water supply, the composition of the water, the type installed equipment waterworks and its location (distance from consumers), the cost of reagents and disinfection equipment.

Chlorination

The most important advantage of this disinfection method is the ability to ensure the microbiological safety of water at any point in the distribution network, at any time, during its transportation to the user - precisely due to the aftereffect. After introducing a chlorinating agent into water, it retains its activity against microbes for a very long time, inhibiting their enzyme systems along the entire route of water through water supply networks from the water treatment facility (water intake) to each consumer. Due to its oxidative properties and aftereffect, chlorination prevents the growth of algae, helps remove iron and manganese from water, destroys hydrogen sulfide, decolorizes water, maintains microbiological cleanliness of filters, etc.

Despite the fact that chlorination has so far been the most common method of disinfection, this method also has some limitations in its use, for example:

As a result of chlorination, organochlorine compounds (OCCs) can form in the treated water;

Traditional chlorination methods in some cases are not a barrier to the penetration of a number of bacteria and viruses into water;

Chlorination of water carried out on a large scale has caused a widespread proliferation of chlorine-resistant microorganisms;

Solutions of chlorine-containing reagents are corrosive, which sometimes causes rapid wear of equipment;

Chlorine dioxide

The use of chlorine dioxide for water disinfection has several advantages:

Chlorine dioxide does not form trihalomethanes when interacting with organic substances, while helping to reduce the concentrations of iron and manganese in water;

It is an effective oxidizing agent and disinfectant for all types of microorganisms, including cysts (Giardia, Cryptosporidium), spore forms of bacteria and viruses;

The disinfectant effect is practically independent of the pH of the water, while the effectiveness of chlorine decreases as the pH value deviates from pH=7.4; - deodorizes water, destroys phenols - sources of unpleasant taste and odor;

Does not form bromates and organobromine disinfection by-products in the presence of bromides.

The main disadvantage of using chlorine dioxide is the formation of by-products - chlorates and chlorites, the content of which in drinking water must be controlled.

Sodium hypochlorite

Sodium hypochlorite has a number of valuable properties. Its aqueous solutions do not have suspensions and therefore do not require settling, unlike bleach.

The use of sodium hypochlorite for water treatment does not increase its hardness, since it does not contain calcium and magnesium salts like bleach or calcium hypochlorite.

The bactericidal effect of a NaClO solution obtained by electrolysis is higher than that of other disinfectants whose active principle is active chlorine.

In addition, the solution has an even greater oxidizing effect than solutions prepared chemical method, because it contains more hypochlorous acid (HClO).

Disadvantage this method is that aqueous solutions of sodium hypochlorite are unstable and decompose over time even at room temperature.

The use of chlorine-containing reagents (bleach, sodium and calcium hypochlorites) for water disinfection is less dangerous in maintenance than the use of chlorine and does not require complex technological solutions.

True, the reagent facilities used in this case are more cumbersome, which is associated with the need to store large quantities of drugs (3-5 times more than when using chlorine). The volume of transportation increases by the same amount.

During storage, partial decomposition of the reagents occurs with a decrease in chlorine content. In this regard, it is necessary to equip a forced-exhaust ventilation system and observe safety measures for operating personnel.

Solutions of chlorine-containing reagents are corrosive and require equipment and pipelines made of stainless materials or with anti-corrosion coating; they are usually not used for individual water supply.

Analyst

Traditional means of water treatment by chlorinating it with molecular chlorine are relatively ineffective, not safe enough in environmental and toxicological terms, cause the appearance of a characteristic irritating odor of water, allergic and itchy irritations of the skin of people, and worsen the organoleptic properties of water. However, the ever-increasing shortage of chlorine-containing preparations, a sharp increase in their prices, increased environmental requirements, and the influence of pan-European water treatment standards have led to the need to search for new methods of disinfection. In addition, with prolonged use of the same product, microorganisms adapt to its action and create a risk of infection.

A qualitatively new disinfectant for water disinfection is Anolyte, synthesized as a result of an electrochemical process of a mixture of oxidants.

Anolyte is primarily an effective disinfectant. The analyte is capable of destroying viruses, bacteria, fungi and other microorganisms. Moreover, regardless of the frequency and duration of its use, bacteria do not develop an addiction to it and Anolyte meets the requirements for disinfectants. The disinfectant has good bactericidal and antifungal properties and is low cost. This disinfection solution can and should be used in places where people and animals are present, since its low toxicity makes it possible to carry out disinfection in the presence of people and animals, which distinguishes it from other solutions used for disinfection. Neutral anolyte ANK is absolutely safe, environmentally friendly and completely biodegradable.

Anolyte also has properties detergent, washing and disinfecting any objects in the room. The high degree of sporicidity of the disinfectant allows it to be used as a means for sterilization in centers infectious diseases.

Anolyte is produced at the site of operation in the required quantity.

Anolyte solution is used:

In medicine for disinfection of premises in hospitals, clinics, clinics, dental clinics, in medical centers (including in infectious diseases wards during people’s stay);

In public places (gyms, transport, public places crowds of people, public toilets)

In everyday life (disinfection of any objects in everyday life, as well as fruits, vegetables, meat, etc. food products in order to increase shelf life)

In the Ministry of Emergency Situations (air disinfection (by spraying), transport disinfection, disinfection of epidemiologically dangerous burial sites)

IN agriculture and agro-industrial complex (disinfection of livestock buildings and other agricultural facilities, treatment of plants in greenhouses to combat viral and bacterial diseases, treatment of irrigation water and water treatment, disinfection of seeds and seedlings before sowing and planting, processing of finished agricultural products to increase their shelf life, silage green feed)

IN food industry(processing of raw materials in food processing plants, for example, for the purpose of disinfection and increasing shelf life; disinfection of livestock and poultry carcasses in slaughterhouses and meat processing plants; disinfection of fish and seafood)

Main advantages of Anolyte:

• Environmentally friendly solution
• safe against all warm-blooded organisms (both through external contact and ingestion)
• has an embalming effect, which stops skin aging during contact with the solution and long time after that
• does not cause irritation or allergic reactions
• Effectively removes biological film in water circulation systems and on pool walls
• does not form harmful by-products (toxic) of chlorination
• effective against all known viruses, bacteria, algae, fungal organisms and spores
• safe for people and environment
• cost-effective thanks to patented design new technology and the best operational and consumer indicators

The main disadvantage of use is that it requires high initial equipment costs and low productivity.

Iodization

Research shows that the iodization method is effective against bacteria and viruses and is not effective enough against microbial toxins and phenolic compounds.

Another limitation on the spread of the iodization method is the appearance of a specific odor when iodine is dissolved in water.

Therefore, iodization of water for the purpose of disinfection does not compete with traditional chlorination, despite the fact that iodine, unlike chlorine, has such advantages as inertness towards ammonia and its derivatives, as well as resistance to solar radiation.

Treatment of water with iodine for disinfection purposes has not found widespread use, although attempts to iodize tap water have been attempted several times.

Currently, water treatment with iodine is used only for low flow rates or in cases where special water disinfection schemes are used. Thus, in some cases, iodine is used to disinfect water in swimming pools.

In modern practice, for the disinfection of drinking water by iodization, it is proposed to use special ion exchangers saturated with iodine.

As water passes through them, iodine is gradually washed out of the ion exchanger, passing through the water. This solution is only possible for small-sized individual installations in household systems water purification.

In such systems, iodization of water is carried out due to additional installation into one of the cleaning stages of a special filter element.

Significant disadvantages are the change in iodine concentration during operation, the impossibility of precise dosing into running water and the lack of control of its concentration.

Bromination

Bromine affects microorganisms, kills viruses, bacteria, fungi, helps remove organic impurities from water, and is effective in combating algae.

Compounds based on bromine are resistant to solar radiation.

However, despite all its advantages, the water bromination method is very expensive, so it is not widely used in drinking water purification and is used mainly for disinfecting water in small pools and spas.

Ozonation

When there is increased bacterial contamination of the water source or when it contains pathogenic microorganisms, enteroviruses and Giardia cysts that are resistant to traditional chlorination, ozone is especially effective.

The mechanism of action of ozone on bacteria has not yet been fully elucidated, but this does not prevent its widespread use.

Ozone is a much stronger oxidizing agent than chlorine (at the doses of both reagents used).

In terms of speed, ozone is more effective than chlorine: disinfection occurs 15-20 times faster. Ozone has a destructive effect on spore forms of bacteria, 300-600 times stronger than chlorine.

It should be noted that ozone has such an important property as its antiviral effect. Enteroviruses, in particular those excreted from the human body, enter wastewater and, therefore, can often enter water surface sources used for drinking water supply.

The water ozonation method is technically complex and the most expensive among other methods of drinking water disinfection.

The technological process includes successive stages of air purification, its cooling and drying, ozone synthesis, mixing of the ozone-air mixture with the treated water, removal and destruction of the residual ozone-air mixture, and its release into the atmosphere.

All this limits the use of this method in everyday life.

From a hygienic point of view, ozonation is one of the best ways disinfection of drinking water.

With a high degree of disinfection, it ensures its best organoleptic characteristics and the absence of highly toxic and carcinogenic products in purified water.

Ozone destroys known microorganisms 300-3000 times faster than any other disinfectant.

Ozonation does not change the acidity of water and does not remove necessary for a person substances. Residual ozone quickly turns into oxygen (O2) and enriches the water with it.

During ozonation, harmful reaction by-products do not have time to arise, at least in noticeable quantities.

There are some disadvantages of using ozonation, which impose corresponding restrictions on its use:

1. The ozonation method is technically complex and requires high expenses electricity and the use of complex equipment that requires highly qualified maintenance.

2. The prolonged action of ozone is significantly less than that of chlorine, due to its rapid destruction, so re-contamination of water during ozonation is more likely than during chlorination.

3. Ozonation can cause (especially in highly colored waters and waters with a large amount of “organic matter”) the formation of additional sediments, so after ozonation it is necessary to provide for filtering the water through activated carbon.

As a result of ozonation, by-products are formed, including: aldehydes, ketones, organic acids, bromates (in the presence of bromides), peroxides and other compounds.

When exposed to humic acids, where there are aromatic compounds of the phenolic type, phenol may appear.

Oligodynamy

Oligodynamy is the effect of noble metal ions on microbiological objects.

When talking about oligodynamy, as a rule, three metals are considered - gold, copper and silver.

The most common method for practical purposes is the use of silver; copper-based bactericidal solutions are sometimes used.

It has been scientifically proven that silver in ionic form has bactericidal, antiviral, pronounced antifungal and antiseptic effects and serves as a highly effective disinfectant against pathogenic microorganisms that cause acute infections. The effect of killing bacteria with silver preparations is very great.

However, when choosing silver as a disinfectant, you must remember that silver is a heavy metal. Like other heavy metals, silver can accumulate in the body.

“Silver” water has bactericidal properties at fairly high concentrations of silver, about 0.015 mg/l. At low concentrations (10-4... 10-6 mg/l.), silver has only a bacteriostatic effect, i.e. it stops the growth of bacteria, but does not kill them. Spore-forming varieties of microorganisms are practically insensitive to silver.

Silver plating of activated carbon cartridges is used in household filters. This is done in order to prevent the filters from fouling with microorganisms, since the filtered organic substances are good nutrient medium for many bacteria.

The use of active carbons and cation exchangers saturated with silver

Currently, activated carbon is used in many water purification processes, the food industry, and chemical technologies. The main purpose of coal is the adsorption of organic compounds.

It is the filtered organic matter that provides the ideal breeding ground for bacteria to multiply when water movement stops.

Applying silver to activated carbon prevents the growth of bacteria inside the filter due to the bactericidal properties of this metal.

The technology of applying silver to the surface of coal is unique in that silver is not washed off from the surface of the coal during the filtering process.

Despite the fairly high efficiency of oligodynamy in general, we cannot talk about the absolute universality of this method.

The fact is that a number of harmful microorganisms are outside the zone of its action - many fungi, bacteria (saprophytic, spore-forming).

Nevertheless, water passed through such a filter usually retains its bactericidal properties and purity for a long time.

Ultraviolet disinfection

Electromagnetic radiation within wavelengths from 10 to 400 nm is called ultraviolet.

For disinfection of natural and waste water use the biologically active region of the UV radiation spectrum with a wavelength from 205 to 315 nm, called bactericidal radiation.

The largest bactericidal effect(maximum virucidal effect) has electromagnetic radiation at a wavelength of 200-315 nm and maximum manifestation in the region of 260 ± 10 nm.

Modern UV devices use radiation with a wavelength of 253.7 nm.

When passing through water, UV radiation is attenuated due to absorption and scattering effects.

The degree of absorption is determined by the physical and chemical properties of the treated water, as well as the thickness of its layer.

To take this weakening into account, the water absorption coefficient α is introduced, the value of which depends on the quality of the water, especially on the content of iron, manganese, phenol in it, as well as on the turbidity of the water.

As a rule, for water disinfection to be effective, it must meet the following requirements:

transparency - not lower than 85%;

amount of suspended particles - no more than 1 mg/l;

hardness - less than 7 mmol/l;

manganese - no more than 0.1 mg/l;

solid suspended particles - less than 10 mg/l;

turbidity - no more than 2 mg/l for kaolin;

color - no more than 35 degrees;

the number of coliform bacteria is not more than 10,000 per liter.

Therefore, in all cases where the water quality differs from the standard drinking water, the selection of UV equipment should be made by specialists.

There is no problem of overdose with UV irradiation of water. Increasing the dose does not lead to hygienically significant unfavorable changes in the properties of water and the formation of by-products.

Advantages of the method:

The least “artificial” is ultraviolet rays;

The versatility and effectiveness of defeating various microorganisms - ultraviolet rays destroy not only vegetative, but also spore-forming bacteria, which, when chlorinated with usual standard doses of chlorine, retain their viability;

Physico- chemical composition the treated water remains unchanged;

No upper dose limit;

There is no need to organize a special safety system as with chlorination and ozonation;

There are no secondary products;

There is no need to create a reagent facility;

The equipment operates without special maintenance personnel.

Disadvantages of the method:

Decrease in efficiency when treating poorly purified water (turbid, colored water does not “transparent” well);

Periodic cleaning of lamps from deposits and sediments, required when processing cloudy and hard water;

There is no “aftereffect”, i.e. the possibility of secondary (after radiation treatment) contamination of water is not excluded.

You need to understand that there is no one most universal or most correct method of water disinfection. Each of the methods can provide disinfection only under properly selected conditions, since each of the methods has its own limitations for use.

Below is a comparison of the three main methods of water disinfection: chlorination, ozonation and UV disinfection:

Each of the three technologies, if used in accordance with the standards, can provide the necessary degree of bacterial inactivation, in particular, for indicator bacteria of the E. coli group and the total microbial number.

In relation to cysts of pathogenic protozoa, none of the methods provides a high degree of purification. To remove these microorganisms, it is recommended to combine disinfection processes with turbidity reduction processes.

Ozone and ultraviolet have a fairly high virucidal effect at practical doses. The chlorination method is less effective against viruses.

The technological simplicity of the chlorination process and the non-scarcity of chlorine determine the widespread use of this particular disinfection method.

The ozonation method is the most technically complex and expensive compared to chlorination and UV disinfection.

UV radiation does not change the chemical composition of water even at doses much higher than practically necessary. Chlorination can lead to the formation of undesirable organochlorine compounds that are highly toxic and carcinogenic. During ozonation, it is also possible to form by-products classified by regulations as toxic - aldehydes, ketones and other aliphatic and aromatic compounds.

Ultraviolet radiation kills microorganisms, but the resulting “fragments” cell walls bacteria, fungi, virus fragments) remain in the water, so subsequent filtration is recommended.

Only chlorination ensures water conservation in doses of 0.3-0.5 mg/l, i.e., it has the necessary long-term effect.

Ultrasound exposure

Ultrasonic water disinfection is based on the use of the cavitation phenomenon.

The bactericidal effect of ultrasound strongly depends on the intensity of vibrations. For the complete destruction of pathogenic microflora, including a number of spores and fungi, sufficiently large doses of absorbed energy are required, which can be ensured over a wide range of practical application method is difficult.

Therefore, it is advisable to use ultrasonic exposure in combination with some other type of water treatment, for example, UV irradiation.

The quality of ultrasonic water disinfection is not affected by such parameters as high turbidity and color of water, the nature and number of microorganisms, as well as the presence of dissolved substances in water. The degree of water disinfection depends only on the intensity of ultrasonic vibrations.

Electrochemical disinfection method

When implementing electrochemical methods of water preparation, liquid disinfection is ensured, since electrolysis of aqueous solutions is almost always accompanied by the formation of strong disinfectants in the electrolyte volume.

Overlay electric field on the treated liquid can cause irreversible aggregation of microorganisms, which allows them to be separated on a filter for coarse impurities.

Chlorine and its oxygen compounds are the most widely used and popular means of water disinfection.

The electrochemical production of chlorine from chloride solutions followed by its dissolution in the electrolyte volume leads to the formation of powerful bactericidal agents HClO and ClO- - hypochlorous acid and hypochlorite ion, respectively.

IN recent years are most widely used electrolysis plants, allowing you to obtain reagents for water disinfection directly at the point of consumption.

To select a disinfection method in your case, please contact our specialists, send input data to email: [email protected] or by phone +7 495 665 22 60.

Disinfection and disinfection of water are one and the same process. It is aimed at the complete or partial destruction of viruses, bacteria contained in the liquid, cleansing it of dust, debris, etc. The purpose of the event is to protect people from viral and infectious diseases, food poisoning, helminthic infestation. In this article we will introduce you to several methods of water disinfection - traditional and innovative, industrial and suitable for use in field conditions.

Cleaning methods

First of all, let us note the fact that complete purification of all elements contained in it (including bacteria) will make the liquid completely unsuitable for drinking and cooking. Therefore, you need to wisely choose a method of water disinfection and be confident in its high-quality implementation.

Disinfection should always be preceded by a chemical and biological examination of the liquid. Based on its results, one of the disinfection methods is chosen:

• Chemical, reagent.
• Combined.
• Reagent-free, physical.

Each of them is a method of water disinfection, but according to its own specific method. For example, chemical is exposure using coagulant reagents, physical methods- reagent-free exposure. There are also innovative ones that we will definitely examine throughout the material.

Interesting application combined methods- this is the use of both physical and chemical cleansing alternately. It is considered today the most effective in disinfection - not only allows you to get rid of bacteria, but also helps to prevent their return visit. The use of several methods of water disinfection also guarantees its purification from the maximum amount of pollutants.

Chemical methods

In particular, this is the treatment of liquid with various substances - chemical coagulants. The most common:

• chlorine;
• ozone;
• sodium hypochlorite;
• metal ions, etc.

The effectiveness of these methods of disinfecting drinking water depends on the most accurately determined dose of the acting reagent, on the proper time of its contact with the liquid being purified.

The appropriate dosage is determined both by the calculation system and by trial disinfection, after which the water is taken for analysis. It is important not to miscalculate in the sense that small dose chemical reagents are not only powerless against viruses and infections, but can also help increase their activity. For example, the same ozone in small quantities kills only part of the bacteria, releasing special compounds that awaken dormant microorganisms, stimulating them to accelerate their reproduction.

Hence the dose is always calculated in excess. But methods are one thing, and drinking methods are another thing. In the latter case, the excess should be such as not to cause poisoning by disinfectants in people consuming the liquid.

We invite you to learn more about the chemical technique.

Chlorination

If you ask ordinary people: “Indicate the simplest way to disinfect water,” many will immediately mention chlorination. And for good reason - as a method of disinfection it is very common in Russia. This is explained undoubted advantages chlorination:

• Easy to use and maintain.
• Low price of the active substance.
• High efficiency.
• The subsequent effect after application is that secondary growth of microorganisms does not occur even with a minimal excess dose of chlorine.
• Control over the odor and taste of water.
• Keeping filters clean.
• Prevents the formation of algae.
• Destruction of hydrogen sulfide, removal of iron and manganese.

However, the product also has its disadvantages:

• When oxidized, it has a high degree of toxicity, mutagenicity, and carcinogenicity.
• Subsequent liquid purification after chlorine activated carbon does not completely save it from compounds formed by chlorination. Highly resistant, they can make drinking water unsuitable for drinking and clog rivers and other natural bodies of water along the flow of wastewater.
• The formation of trihalomethanes, which have a carcinogenic effect on human body. They are what promote growth cancer cells. And boiling, the easiest way to disinfect water, aggravates the situation. In the chlorinated liquid, dioxin is formed after it - a dangerous toxic substance.
• Research shows that chlorinated water also contributes to the development of diseases of blood vessels, gastrointestinal tract, liver, heart, hypertension, and atherosclerosis. Negatively affects the condition of the skin, hair and nails. Destroys protein in the body.

Today, a modern replacement is more effective in disinfection. But a significant disadvantage is that it must be applied immediately at the production site.

Ozonation

Many people consider ozonation to be the most reliable method of water disinfection. Ozone gas is capable of destroying the enzyme system of microbial and viral cells, and oxidizing some compounds that give fluid bad smell.

The advantages of the method are as follows:

• Fast disinfection.
• The most safe disinfection for humans and the environment.

However, ozonation also has a number of disadvantages:

• If the dosage is incorrect, the water will have an unpleasant odor.
• Excess ozone promotes increased metal corrosion. This applies to both water pipes and household appliances, dishes. You need to wait until the gas disintegrates before running water through the pipes.
• The method is quite expensive to use - it requires large waste of electricity, complex equipment, highly qualified service personnel.
• Gas from the production process is toxic and explosive. Belongs to the first hazard class.
• After ozonation, bacteria may multiply again. There is no guarantee of 100% water purification.

Polymer antiseptics

Another popular chemical method is the use of polymer reagents. The most famous today is Biopag. Most often it is used in public swimming pools and water parks.

The advantages of this method of water purification and disinfection:

• Does not harm human or animal health.
• Does not impart a specific odor, taste or color to water.
• Quite easy to use.
• Does not have a corrosive effect on metal.
• Does not cause allergic reactions.

Disadvantages - may irritate the skin and mucous membranes.

Other chemical methods

What methods of water disinfection can be named in in this case? These are several options:

• Disinfection using heavy metal ions, iodine, bromine.
• Disinfection using noble metal ions. Silver is most often used.
• Use of strong oxidizing agents. A common example here would be sodium hypochlorite.

Physical methods

This will not include chemical methods effects on microorganisms in liquid. Their use is most often preceded by filtration and this removes suspended particles, worm eggs, and a significant portion of the microbes in the liquid.

The most common methods:

• Exposure to ultraviolet radiation.
• Exposure to ultrasound.
• Boiling. An effective way water disinfection in natural conditions.

Let's look at each of them in more detail.

UV irradiation

It is important to calculate the required share of the acting energy on a certain volume of water. To do this, multiply the radiation power and the time of contact with the liquid. It is important to first determine the concentration of microorganisms in 1 ml of water, the number of indicator bacteria (in particular, E. coli).

Note that UV rays will have a detrimental effect on microorganisms better than chlorine. Ozone, according to the results of cleaning, will be equal in effectiveness to irradiation. UV rays affect both enzyme metabolism and the cellular structures of bacteria and viruses. What is important is that vegetative and spore forms are destroyed.

The advantages of the method are:

• There is no upper dose threshold, since such irradiation does not form toxic compounds in the water. By increasing it, you can gradually achieve the most best results.
• Great for individual use.
• Long service life of the UV lamp - several thousand hours.

But there are also disadvantages:

• There are no consequences of the event - in order to prevent the return of microorganisms, the water should be disinfected periodically and systematically, without turning off the installation.
• Quartz lamps sometimes become contaminated with deposits of mineral salts. However, this can easily be prevented using regular food grade acid.
• Preliminary purification of water from particles suspended in it is mandatory - by screening the rays, they nullify the entire process.

A method for disinfecting water in the field using UV radiation is demonstrated in the picture.

Ultrasound

The action here is based on cavitation. This is the name for the ability of a number of sound frequencies to form voids that create big difference in pressure. This dissonance leads to rupture of the cell membranes of viruses and bacteria, which leads to the death of microorganisms. Efficiency depends on the intensity of sound vibrations.

This method is not widely used, primarily due to its high cost. Certain equipment and specially trained personnel are required. It is important to remember that ultrasound is dangerous for bacteria only at certain frequencies. Low waves, on the contrary, can cause an acceleration in the growth of the number of microorganisms in the water.

Boiling

The simplest and most common way to disinfect water in the field is, of course, boiling. Its popularity and general recognition is based on many factors:

• Destruction of almost all harmful microorganisms in liquid - viruses, bacteria and bacteriophages, antibiotics, etc.
• Accessibility - you need a heat source capable of heating water to 100 degrees Celsius, and a heat-resistant container.
• Does not affect the taste of the liquid, its color or smell.
• Eliminates gases dissolved in water.
• Excellently fights liquid hardness and softens it.

Comprehensive cleaning methods

From simple ways water disinfection, let's move on to complex ones, which are the most effective in a number of cases. For example, this is a combination of UV irradiation and chlorination, ozonation and chlorination (preventing secondary contamination), reagent-free and reagent methods.

Filtration is often included in this category. But with the peculiarity that each filter cell should be smaller in size than the microorganisms being screened out. This means that its diameter should not exceed 1 micron. But this way you can only fight bacteria. More microscopic pores are used against viruses - with a diameter of less than 0.1-0.2 microns.

On modern market A popular filtration system called "Purifier". The device is distinguished by the fact that it uses several water filtration and disinfection systems. Some models can additionally cool water up to 4 degrees and heat up to 95 degrees.

The installation is applicable in industrial, office and home scales. TO water pipe It is enough to simply connect it with a plastic adapter. Manufacturers assure that the purchase, connection and operation of Purifier will cost the owner less than the delivery of bottled water.

Innovative methods of disinfection

The newest methods of water disinfection today will be electrochemical and electric pulse. On domestic market they are used in such devices as “Emerald”, “Sapphire”, “Aquamarine”.

Their operation is based on the operation of a special electrochemical diaphragm reactor through which water is passed. It, in turn, is divided by a metal-ceramic membrane, which is capable of ultrafiltration into cathode and anode zones.

At the moment when current is supplied to the anode and cathode chambers, solutions begin to form in them - alkaline and acidic. Then - electrolytic formation (its other name is active chlorine). This entire environment is distinctive in that it actively kills the overwhelming number of types of harmful microorganisms. It is also capable of destroying some compounds dissolved in liquid.

The performance of the presented devices mainly depends on two factors: the number of working elements and their design. Some units use catholytes and anolytes (mainly in the medical field). Such disinfection is called ECA technology.

By the way, many misconceptions are associated with it. Some device manufacturers claim that the water processed in their unit becomes healing and even miraculous. However, in reality it is only cleaned and disinfected.

Electric pulse cleaning is the passage of an electric discharge through the water column. Ultra high pressure shock wave, light radiation, ozone formation is a consequence of exposure. All this together is destructive for microorganisms suspended in liquid.

We met different methods water disinfection - simple and complex, traditional and innovative, effective and safe for humans. Each of them has its own advantages and disadvantages. However, the leading factor is harmlessness to the human body and the environment.