State educational institution Omsk region for orphans and children left without parental care,

"Peter and Paul Orphanage"

Ecology lesson

"Water is life"

Prepared

Kuzmina Natalya Nikolaevna

teacher of the first qualification

Muromtsevo, 2015

Lesson “Water is life”

Purpose: to show the need for water for all life on Earth.

Tasks:

Learn to purify water from impurities using improvised materials;

Consolidating children’s system of ideas about the importance of water in human life;

Fostering a love of nature, instilling the skills to use water economically at home.

Equipment: cards, 2 plastic bottles, coal, sand, cotton wool, bandage or gauze, water, 2 filter containers.

Scenario plan:

Introductory part: setting goals.

Main part:

- independent work using cards “The importance of water in human life”

Story “Methods of water purification”;

Practical work “Making a filter”;

3.Final part: summing up the lesson

Progress of the lesson

Introductory part:

Today we will talk to you about her majesty WATER.Water is the most amazing and full of secrets substance.Among all the benefits given to us by nature, water occupies a special place. Water is a unique wealth of living nature. We cannot even imagine our life without water. After all, people need water every day.

Let's list why a person needs water?

(for drinking, cooking, personal hygiene, etc.)

Can a person use all the water?

(children's answers)

Today in class we will talk about the importance of water in human life, ways to purify it from impurities, and the topic of our lesson is “Water is life.”

2. Main part:

Guys, tell me what holiday was celebrated on March 22.

(Children's answers: World Water Day)

Indeed, World Water Day is celebrated on March 22 every year. In our country, World Water Day has been celebrated since 1995. Its motto is: “Water is life.”

How do you understand the motto “Water is life”?

(children's answers)

Tell me, why did it become necessary to create this holiday?

(children's answers: high water consumption, pollution, etc.)

The holiday is designed to emphasize the greatest importance of water in our lives. Constant population growth and the development of industrial production increase the importance of water and exacerbate the problem of the need for its environmental protection.

(independent work using cards “The importance of water in human life”)

Now I suggest you work on the cards; you need to choose the correct ones from the proposed answers. You have 1 minute to complete the task.

Card “The importance of water in human life”

Humidifies oxygen for breathing;

- destroys metabolism;

Regulates body temperature;

Helps the body absorb nutrients;

- contributes to the destruction of vital organs;

Lubricates joints;

Helps convert food into energy;

Participates in metabolism.

According to the International Labor Organization, 70% of the population globe uses poor quality water. Water pollution is a decrease in its quality as a result of the entry into rivers, streams, lakes, seas and oceans of various physical, chemical or biological substances. Water pollution has many causes.

What are the reasons for water pollution?

1. Wastewater into rivers, lakes, seas;

2. environmental disasters: oil spill;

3. industrial emissions

4. Microbiological contamination of water.

Guys, tell me, where does the water we take from the tap come from into our apartments?

(children's answers: from rivers, reservoirs, lakes, underground depths).

Do you think the water that comes to our homes can be considered safe and clean?

(children's answers)

Water does not always meet the requirements for water. But so that the water we drink is clean. What do you think should be done?

(children's answers: purify water, boil, etc.)

There are many ways to purify water from impurities and metals.

Methods of water purification:

1. settling of water.

It is better to stand in a glass container. The water needs to stand for 6-7 hours in an open container. At the same time, chlorine evaporates, and at the bottom of the dish in which the water settles, harmful substances for the body will settle. chemical compounds, heavy elements, salts, etc. Therefore, when about one third of the water remains in the vessel, it must be poured out.

2.Freezing water

Freezing is a great way to rid water of heavy metal salts. After defrosting, water releases a lot of energy, which saturates the human body.Melt ice at room temperature. I'm meltingwater can be drunk immediately after defrosting, it does not need to be boiled, it is already ready for . It is most beneficial for health to consume “live”water on an empty stomach or 20 minutes beforefood.3.Saturation of water with silicon.

Silicon is a powerful water activator and has significant bactericidal properties. Water treated with silicon becomes very tasty and does not spoil for a long time. Silicon can be bought in pharmacies.

4. using activated carbon, which is freely available in pharmacies. Throw coal into the tapwaterat the rate of 1 tablet per 1 liter of water, let stand for 8 hours. Coal will absorb some toxic substances, the metallic taste will disappear from the water, it will become pleasant. Change the tablets after each drainage of water;

Guys, tell me how you can purify water using improvised means if you are in the forest and you have run out of water?

(children's answers)

Independent work"Making a filter"

(On the table are the necessary materials to make a filter for water purification)

Now while the water is passing through the filter. Each group will tell how they made the filter.

3.Final part

Today we talked about water as a priceless gift of nature. But before we use it, we must know that it is clean and safe for health. Drinking water should be clear, free of sand and sediment, odorless and without an “earthy” taste. It should be refreshing and pleasant to the taste.

What methods of water purification did we talk about today?

What new did you learn in class?

And don't forget that important role water is that it is the main element in maintaining human life, i.e. - an indispensable component of all living things. Only where there is water there is life. There is no living thing if there is no water. Thanks everyone for your work.

List of internet sources used

The importance of water in human life.

Water purification at home.

How to purify drinking water

Ecology is a science that studies the laws of nature, the interaction of living organisms with the environment, the foundations of which were laid by Ernst Haeckel in 1866. However, people have been interested in the secrets of nature since ancient times and had a careful attitude towards it. There are hundreds of concepts of the term “ecology”, including different times scientists gave their definitions of ecology. The word itself consists of two particles, from Greek “oikos” is translated as house, and “logos” is translated as teaching.

With the development of technological progress, the state of the environment began to deteriorate, which attracted the attention of the world community. People have noticed that the air has become polluted, species of animals and plants are disappearing, and the water in rivers is deteriorating. These and many other phenomena were given a name -.

Global environmental problems

Most environmental problems have grown from local to global. Changing a small ecosystem in specific point world can affect the ecology of the entire planet. For example, a change in the oceanic Gulf Stream will lead to major climate changes and a cooling of the climate in Europe and North America.

Today, scientists count dozens of global environmental problems. We present only the most relevant of them, which threaten life on the planet:

• — climate change;
• — depletion of fresh water reserves;
• - reduction of populations and extinction of species;
• — depletion of mineral resources;

This is not the entire list of global problems. Let's just say that environmental problems that can be equated to a disaster are pollution of the biosphere and. Every year the air temperature rises by +2 degrees Celsius. The reason for this is greenhouse gases. A world conference dedicated to environmental problems was held in Paris, at which many countries around the world pledged to reduce gas emissions. As a result of the high concentration of gases, the ice at the poles melts, the water level rises, which in the future threatens the flooding of islands and the coasts of continents. To prevent an impending disaster, it is necessary to develop joint action and take actions that will help slow and stop global warming.

Subject of study of ecology

At the moment there are several sections of ecology:

• — general ecology;
• — bioecology;

Each section of ecology has its own subject of study. The most popular is general ecology. She studies the surrounding world, which consists of ecosystems, their individual components - relief, soil, flora and fauna.

The importance of ecology for every person

Caring for the environment has become a fashionable activity today; the phrase “eco” is used everywhere. But many of us do not even realize the depth of all the problems. Of course, it is good that the vast humanity of people has become indifferent to the life of our planet. However, it is worth realizing that the state of the environment depends on each person.

Any inhabitant of the planet can perform daily simple steps which will help improve the environment. For example, you can recycle waste paper and reduce water use, save energy and throw garbage in the trash bin, grow plants and use reusable items. How more people will comply with these rules, the greater the chance of saving our planet.

Greetings, dear friends! A note from my assistant for the development of the “Environmental Safety” group, Ksenia Raldugina.

The first steps of a novice ecologist

Remembering myself in the first 2 weeks of working as an ecologist, I perfectly understand the panic of a novice environmental specialist. You have come to a new team, you need to work, but what to do and how is completely unclear. When I came to the office on my first working day, I was shown a table littered with folders, and the manager announced to me: “I don’t know what you should do, but this is everything that remains from the previous ecologists - figure it out.” That was panic! The first 2-3 weeks my head was just boiling! And the most difficult thing was that there was no one to ask, since, as a rule, there is only one ecologist at the enterprise! Probably everyone has had such a situation at work.

That’s why I decided to write some tips for beginners!

The most important thing is don’t panic! The more panic, the less benefit! Try to get to know your colleagues, find out how work works in the office, watch people, don’t try to do everything at once, you won’t have time anyway!
Regulatory documents in the field of ecology! This is something without which an ecologist specialist would be absolutely nowhere! The basis for your activities in the field of ecology is legislation relating to environmental issues. In this regard, it is necessary to have access to and study current laws, regulations, STB, TCH, SanPiN, etc. The easiest way is to create a regulatory framework for yourself that you can rely on and track changes.
Internet! There are several excellent sites that can help you get information. This includes Anton Khabirov’s website, which provides information in an accessible form, simple and clear.
Websites from supervisory authorities. Incredibly useful for a novice ecologist. There are several official sites, their links are given below:

https://76.rpn.gov.ru/ Rosprirodnadzor
https://www.gks.ru/ Federal Service state statistics
https://www.gosnadzor.ru/ Rostechnadzor
and others.

It should also be taken into account that, according to the specifics of any enterprise, there are main directions of its impact on the environment.
These are:

Air pollution, water resources, soils;
use of natural resources;
physical factors (noise, thermal radiation, etc.).

In order to determine what impact an enterprise has on the environment, and, accordingly, what legislative acts its activities are regulated, it is necessary to study the enterprise: its structure, production processes, available documentation on environmental issues.

Where to start?

Armed with a diagram of the organization’s territory with the location of buildings and structures, I recommend taking a tour of the enterprise’s territory. The main goals of this walkthrough:

Familiarization with the activities of the enterprise;
getting to know the people in charge at production;
detection of existing violations (of course, it will be difficult to judge them for now, but try).

It is advisable to invite one of the production workers, for example, the chief engineer. This person is usually always up to date with current events.
During the excursion we pay attention to waste: what kind of waste is generated, how it is stored, is there a temporary storage area, how many containers are there, how are they installed, etc.

We are looking for sources of emissions. Under the pipes there may be blacksmiths, boiler rooms, treatment equipment - all these are stationary sources of emissions.

It is important to find the reset point. Maybe into a water body, or maybe just into a well, agreed upon with the water utility.

Along the way, we study technology in conversations. What exactly does your enterprise do, what is the technology, what kind of equipment and raw materials are used.
After getting your bearings, you need to look at the documents that were left in the office.
The list of internal documentation that should be in one form or another is given below:
Instructions and regulations. Have they been approved and with whom have they been agreed upon?
Orders, who was appointed responsible for what.
Trained – who was trained, what and when.
Correspondence with supervisory authorities.
Analysis protocols (production control - there are water, soil and air, there are also various sanitary controls).
Agreements for the transfer of waste (landfill, mercury lamps, oils, batteries, etc., depending on the list of waste).

List of documents provided by legal entities and individual entrepreneurs during inspection by the regional state environmental supervision department

1. Basic documents characterizing the object economic activity:

1. Certificate of state registration of a legal entity;
2. Certificate of registration of a legal entity with the tax authority at its location in the territory Russian Federation;
3. Extract from the Unified State Register of Legal Entities;
4. Charter of a legal entity;
5. Foundation agreement of a legal entity;
6. Certificate of registration with the tax authority of an individual at the place of residence on the territory of the Russian Federation;
7. Certificate of state registration of an individual as an individual entrepreneur;
8. Extract from the Unified State Register of Individual Entrepreneurs;
9. Documents for land use;
10. Available licenses;
11. Structure of the enterprise: main and auxiliary production;
12. List of tenants;
13. Section of the EIA (environmental impact assessment) in the project for the construction of the facility;
14. Conclusion of the state environmental assessment on the project for the construction of the facility;
15. The act of putting the facility into operation.

2. Documents evidencing the organization of industrial environmental control at the enterprise:

1. An administrative document on the organization of environmental service at the site of economic and other activities;
2. An administrative document appointing a person responsible for carrying out industrial environmental control;
3. Materials characterizing the results of industrial environmental control.

3. Documents based on the results of inspections of compliance with the requirements of environmental legislation by state environmental control bodies:

1. Acts based on the results of previous inspections;
2. Instructions from state environmental control bodies to eliminate violations of environmental legislation;
3. Protocols on administrative offenses, decisions on the imposition of fines;
4. Orders for the enterprise and action plans to eliminate violations established in inspection reports;
5. Reports on compliance with requirements.

4. Forms of state statistical reporting:

1. No. 2-tp (air) “Information on the protection of atmospheric air”;
2. No. 2-tp (vodkhoz) “Information on water use.”
3. No. 2-tp (toxic waste) “On the generation, receipt, use and disposal of toxic waste from production and consumption.”

5. Documents in the field of atmospheric air protection:

1. Inventory of emissions of pollutants into the atmospheric air;
2. Draft standards for permissible emissions of pollutants into the atmosphere (MPE);
3. Schedule of control at the enterprise over compliance with MPE standards at emission sources;
4. Action plan to reduce emissions of pollutants into the atmosphere in order to achieve MPE standards;
5. Annual permit for the emission of pollutants into the atmosphere; (if required)
6. Annual explanatory note on the constancy of the number of sources of pollutant emissions, quality and quantitative composition emitted substances, the invariability of the technological process, the consumption and range of raw materials and supplies used, the preservation of the volumes of products determined for the year of development and establishment of permissible emission standards; (if any)
7. Technical report on monitoring compliance with established standards for emissions of pollutants into the atmosphere according to the control schedule;
8. Report on the implementation of the action plan to reduce emissions of pollutants into the atmosphere in order to achieve MPE standards;
9. Primary accounting documentation for atmospheric air protection:
POD-1 “Logbook of stationary sources of pollution and their characteristics”,
POD-2 “Logbook of implementation of measures to protect atmospheric air”,
POD-3 “Logbook of operation of gas cleaning and dust collection installations”;
10. Order for the enterprise on the appointment of a person responsible for the operation and maintenance of gas purification plants and on his functions;
11. Job Descriptions for personnel operating a gas purification plant;
12. Passports for each gas purification unit;
13. Results of inspections of the technical condition of gas purification installations;
14. Acts of verification of compliance of the actual operating parameters of gas cleaning equipment with the design ones;
15. Instructions for operation and maintenance of gas purification plants;
16. Order on the procedure for maintaining logs of the operation of gas purification installations;
17. Schedule of preventative (current) repairs of gas purification units;
18. Regime cards for boiler units;
19. Certificates for breathing valves of tanks with petroleum products;
20. Documentation on the implementation of measures to temporarily reduce emissions of pollutants from the facility during periods of adverse meteorological conditions (AMC), including:
order from the head of the enterprise on the procedure for transitioning to specified modes during periods of adverse meteorological conditions (NMC), indicating the persons responsible for carrying out measures at the enterprise, production, workshops, sites and other facilities, as well as persons responsible for organizing the reception of notifications and the introduction of measures to reduce emissions ;
log of receipt of warnings about NMU;
action plan to prevent emergency emissions of air pollutants;
21. Documentation on the protection of atmospheric air during the operation of vehicles, including:
daily log of vehicle use;
daily fuel consumption log;
mileage log;
a log of recording the results of inspections of cars with gasoline engines for compliance with environmental requirements;
log of smoke measurements when checking vehicles with diesel engines;
schedule maintenance vehicles.

6. Documents in the field of use and protection water bodies:

1. Order for the enterprise on the appointment of a person responsible for the operation and maintenance of water communication networks and treatment facilities and on his functions;
2. Balance diagram of direct-flow and recycling water supply and sanitation with indication and numbering of measurement points for water intake (reception) and discharge, as well as points for its transfer to other consumers;
3. Passports for treatment facilities;
4. Work plans for checking the efficiency of treatment facilities;
5. Instructions for operation and maintenance of treatment facilities; primary accounting documentation on water use;
6. Water use agreement;
7. Decision on the provision of water bodies for use;
8. Agreed limits on water use;
9. Standards for maximum permissible discharges of substances (VAT) or for temporarily agreed upon discharge of substances (ATD) entering a water body with wastewater by outlet;
10. Schematic diagram of analytical monitoring of the operation of treatment facilities, compliance with standards for permissible discharges of pollutants into the environment with wastewater and their impact on water bodies;
11. Action plan to achieve standards for permissible discharge of pollutants into the environment with wastewater;
12. Annual permit for the discharge of pollutants;
13. Annual explanatory note containing information about immutability technological processes, consumption and nomenclature of raw materials and materials used and maintaining the volume of products determined for the year of development and establishment of permissible discharge standards;
14. Annual technical report on monitoring compliance with established standards for the discharge of pollutants into the environment with wastewater, in accordance with the control schedule;
15. Annual report on the implementation of the Action Plan to achieve the standards for permissible discharge of pollutants into the environment with wastewater, indicating the funds disbursed;
16. Documentation for the implementation of measures in case of extreme pollution of a water body, including an emergency response plan in case of pollution of a water body.

7. Documents in the field of control over geological study, rational use and protection of subsoil:

1. License for the right to use subsoil;
2. Land management documentation;
3. Geological and surveying documentation;
4. Documents confirming the implementation of regular payments for the use of subsoil;
5. Mining allotment to a subsoil plot provided for use;
6. Technical design for the development of a mineral deposit;
7. Registration of a subsoil plot as a hazardous industrial facility;
8. Annual approved standards for losses of industrial property;
9. Coordinated plans for the reclamation of subsoil areas.

8. Documents on the management of production and consumption waste:

1. Order on the appointment of persons authorized to work with hazardous waste;
2. Order on sending persons authorized to work with hazardous waste for training or retraining;
3. The procedure for carrying out production control in the field of waste management;
4. Payment documents for waste removal;
5. Certificate of registration of the waste disposal facility in state register waste disposal facilities (for individual entrepreneurs or legal entities that have on their balance sheet or operate waste disposal or long-term storage facilities (landfills, sludge dumps, tailings dumps, sludge dumps, ash dumps, etc.);
6. Plan of ongoing (planned) measures to reduce the impact of generated waste on the environment;
7. List of waste generated at the enterprise (waste accounting is carried out using the federal waste classification catalogue);
8. Results of determining the hazard class of generated waste;
9. Passports of hazardous waste, indicating the waste code in accordance with the Federal Waste Classification Catalog (FKKO);
10. License for hazardous waste management activities;
11. Certificates (certificates) for the right to work with hazardous waste for persons authorized to handle hazardous waste;
12. Draft standards for waste generation and limits on their disposal;
13. Limits on waste disposal;
14. Measures to monitor the state of the environment at waste storage and disposal sites (sites) and the frequency of their implementation;
15. Annual technical reports on the consistency of the production process, the raw materials used and the waste generated.

9. Documents of the enterprise laboratory for monitoring environmental impacts:

1. Laboratory passport;
2. Certificates of verification of measuring instruments by the state metrological service;
3. Sampling reports and logs of their registration;
4. Certified measurement techniques;
5. Logs of environmental impact monitoring results.

10. Documents in the field of organization and functioning of specially protected natural areas(SPNA):

1. Regulations on the organization of protected areas;
2. Passport of the protected area;
3. Security obligation;
4. Inventory registration card for taxometric description of dendrological objects.

I wish you good luck in your work, colleagues! Good luck!

Introduction
1. Classification of hydrosphere pollution
2. Water: its properties and meaning
3. The water cycle in nature
4. Water quality
5. Impact of water pollution on human health
6. Modern methods of water purification
Conclusion
References

Introduction

Water is one of the most amazing substances on our planet. We can see it in solid (snow, ice), liquid (rivers, seas) and gaseous (water vapor in the atmosphere) states. All living nature cannot do without water, which is present in all metabolic processes. All substances absorbed by plants from the soil enter them only in a dissolved state. In general, water is an inert solvent, that is, a solvent that does not change under the influence of the substances it dissolves. It was in water that life once originated on our planet. Thanks to the oceans, thermoregulation occurs on our planet. A person cannot live without water. Finally, in the modern world, water is one of the most important factors determining the location of production forces, and very often a means of production. So, the importance of water and the hydrosphere - the watery shell of the Earth - cannot be overestimated. Right now, when the growth rate of water consumption is enormous, when some countries are already experiencing an acute shortage of fresh water, the issue of reducing fresh water pollution is especially acute.

The use of water for economic purposes is one of the links in the water cycle in nature. But the anthropogenic link of the cycle differs from natural themes, that in the process of evaporation only most Water used by humans is returned to the atmosphere desalinated. The other part (about 90%) is discharged into rivers and reservoirs in the form of wastewater contaminated with industrial waste.

It is of great importance to meet the needs of the population for drinking water in their places of residence through centralized or non-centralized drinking water supply systems. The sources of centralized water supply are surface water, the share of which in the total volume of water intake is 68%, and groundwater – 32%. IN rural areas The predominant use for drinking purposes is of structures and devices of decentralized household and drinking water supply systems. Water from wells, springs and other sources of decentralized water supply is not protected from pollution and therefore poses a high epidemiological danger.

In recent years, almost all surface water supplies have been exposed to harmful anthropogenic pollutants. 70% of surface waters and 30% of underground waters have lost their drinking value and moved into the categories of pollution - “conditionally clean” and “dirty”. Almost 70% of the population of the Russian Federation uses water that does not comply with GOST “Drinking Water”. Pollution of groundwater used for water supply is increasing, including petroleum products, heavy metals, pesticides and other harmful substances that enter aquifers with wastewater.

1. Classification of hydrosphere pollution

The hydrosphere is the water shell of the Earth, which is a collection of seas, lakes, rivers, swamps, glaciers and groundwater.

Every year people spend about 3000 km 3 of water, of which 150 km 3 is irrevocable. Agriculture consumes the most water.

In industry, water is used for the following purposes:

• Preparation of solutions.
• Cooling and heating of liquids and gases.
• For thermal power purposes.
• For purification of solutions and gas mixtures.
• For transportation of raw materials.
• To remove waste.

Sources of hydrosphere pollution are:

1. Atmospheric waters that wash natural and artificial pollution from the air.
2. Industrial wastewater.
3. Domestic wastewater.

Every year, about 1 trillion m3 of wastewater is generated worldwide. Of these, approximately 20% are discharged without treatment.

The following types of wastewater are generated during technological processes:

1. Reaction waters are formed during a reaction that releases water. Contaminated as starting products, both intermediate and final.
2. Waters contained in raw materials and starting materials in their original and bound form. Contaminated similarly to reaction waters.
3. Wash waters are formed after washing equipment, raw materials, and containers. Contaminated with initial and final products.
4. Water absorbents and extractants.
5. Cooling waters generally do not come into contact with technological products and can be used in recycling water supply systems.
6. Domestic water.
7. Atmospheric precipitation flowing from industrial sites is especially aggressive, because... polluted by industrial emissions.

Hydrosphere pollution is significantly more dangerous than atmospheric pollution for the following reasons:

1. Regeneration or self-cleaning processes occur in aquatic environment significantly slower than in the atmosphere.
2. Sources of water pollution are more diverse.
3. Natural processes occurring in the aquatic environment are more sensitive to pollution. In themselves, they are of greater importance for life on Earth than the processes occurring in the atmosphere.

Among the pollution of various types of environment, chemical pollution natural waters are of particular importance. Let's take a closer look at chemical pollution of natural waters. Any body of water or water source connected with his surroundings external environment. It is influenced by the conditions for the formation of surface or underground water flow, various natural phenomena, industry, industrial and municipal construction, transport, economic and domestic human activities. The consequence of these influences is the introduction of new, unusual substances into the aquatic environment - pollutants that worsen the quality of water. Pollutants entering the aquatic environment are classified differently, depending on approaches, criteria and objectives. Thus, chemical, physical and biological contaminants are usually isolated.

Chemical pollution is a change in natural chemical properties water due to an increase in its content harmful impurities both inorganic (mineral salts, acids, alkalis, clay particles) and organic nature(oil and oil products, organic residues, surface- active substances, pesticides).

The main inorganic (mineral) pollutants of fresh and sea waters are a variety of chemical compounds that are toxic to the inhabitants of the aquatic environment. These are compounds of arsenic, lead, cadmium, mercury, chromium, copper, fluorine. Most of them end up in water as a result of human activity. Heavy metals are absorbed by phytoplankton and then transferred along the food chain to higher organisms.

Among the main sources of hydrosphere pollution with minerals and nutrients, food industry enterprises and agriculture should be mentioned. About 16 million tons are washed away from irrigated lands annually. salts Waste containing mercury, lead, and copper is localized in certain areas near the coast, but some of it is carried far beyond the territorial waters. Mercury pollution significantly reduces primary products marine ecosystems, suppressing the development of phytoplankton. Waste containing mercury typically accumulates in the sediments of bays or river estuaries. Its further migration is accompanied by the accumulation of methyl mercury and its inclusion in the trophic chains of aquatic organisms. Thus, Minamata disease, first discovered by Japanese scientists in people who ate fish caught in Minamata Bay, into which industrial wastewater containing technogenic mercury was uncontrolled, became notorious.

Among the soluble substances introduced into the ocean from land, not only minerals but also minerals are of great importance for the inhabitants of the aquatic environment. nutrients, but also organic residues. The removal of organic matter into the ocean is estimated at 300 - 380 million tons/year. Wastewater containing suspensions of organic origin or dissolved organic matter has a detrimental effect on the condition of water bodies. As they settle, the suspensions flood the bottom and delay the development or completely stop the vital activity of these microorganisms involved in the process of self-purification of water. When these sediments rot, they can form harmful compounds and poisonous substances such as hydrogen sulfide, which lead to the contamination of all water in the river. The presence of suspensions also makes it difficult for light to penetrate deep into the water and slows down the processes of photosynthesis. One of the main sanitary requirements requirements for water quality is the content in it required quantity oxygen. Harmful effect cause all the pollutants that in one way or another contribute to a decrease in the oxygen content in water. Surfactants - fats, oils, lubricants form a film on the surface of the water that prevents gas exchange between water and the atmosphere, which reduces the degree of oxygen saturation of the water. A significant volume of organic substances, most of which are not characteristic of natural waters, is discharged into rivers along with industrial and domestic wastewater. Increasing pollution of water bodies and drains is observed in all industrial countries.

Due to the rapid pace of urbanization and the somewhat slow construction of treatment facilities or their unsatisfactory operation, water basins and soil are polluted by household waste. Pollution is especially noticeable in slow-flowing or non-flowing water bodies (reservoirs, lakes). By decomposing in the aquatic environment, organic waste can become a breeding ground for pathogenic organisms. Water contaminated with organic waste becomes practically unsuitable for drinking and other needs. Household waste is dangerous not only because it is a source of certain human diseases (typhoid fever, dysentery, cholera), but also because it requires a lot of oxygen to decompose. If household wastewater enters a body of water in very large quantities, the content of dissolved oxygen may drop below the level necessary for the life of marine and freshwater organisms.

2. Water: its properties and meaning

The most important thing for life is water. Water is of paramount importance in most chemical reactions, in particular biochemical ones. The ancient position of the alchemists - “bodies have no effect until they are dissolved” - is largely true.

Water - universal solvent. It has a high heat capacity and at the same time high thermal conductivity for liquids. These properties make water an ideal liquid for holding thermal equilibrium body.

Due to the polarity of its molecules, water acts as a structure stabilizer.

Water - a source of oxygen and hydrogen, it is the main medium where biochemical and chemical reactions take place, the most important reagent and product of biochemical reactions.

Water is characterized by complete transparency in the visible part of the spectrum, which is important for the process of photosynthesis and transpiration.

Water practically does not compress, which is very important for giving shape to organs, creating turgor and ensuring a certain position of organs and parts of the body in space.

Thanks to water, osmotic reactions in living cells are possible.

Water — the main means of transport of substances in the body (blood circulation, ascending and descending currents of solutions throughout the plant’s body, etc.).

Water is a very common substance in nature. 71% of the globe's surface is covered with water, forming oceans, seas, rivers and lakes. There is a lot of water in gaseous state in the form of vapors in the atmosphere; it lies in the form of huge masses of snow and ice all year round on the tops of high mountains and in polar countries. In the bowels of the earth there is also water that saturates the soil and rocks. The total water reserves on Earth are 1454.3 million km 3 (of which less than 2% is fresh water, and 0.3% is available for use).

Water is very important in the life of plants, animals and humans. In any organism, water is the medium in which chemical processes, ensuring the vital functions of the body; in addition, it itself takes part in a number of biochemical reactions.

Water is an essential component of almost all technological processes of both industrial and agricultural production.

Let us turn to the general characteristics of the properties of water that make it the most amazing substance on Earth.

And the first, most striking property of water is that water belongs to the only substance on our planet, which, under normal conditions of temperature and pressure, can be in three phases, or three states of aggregation: solid (ice), liquid and gaseous ( steam invisible to the eye).

Water is the most anomalous substance in nature.

First of all, water has an exceptionally high heat capacity compared to other liquids and solids. If the heat capacity of water is taken as one, then, for example, for alcohol and glycerin it will be only 0.3; for sand and rock salt – 0.2; for mercury and platinum – 0.03; for wood (oak, spruce, pine) – 0.6; for iron – 0.1, etc.

Thus, the water in the lake, at the same air temperature and the same solar heat it receives, will heat up 5 times less than the dry sandy soil around the lake, but the water will retain the heat received by the same amount more than the soil.

Another anomaly of water is the unusually high latent heat of vaporization and latent heat of fusion, that is, the amount of heat required to turn liquid into vapor and ice into liquid (in other words, the amount of heat absorbed or released). For example, to turn 1 g of ice into liquid, it is necessary to add about 80 calories, while the ice-water substance itself will not increase its temperature by a fraction of a degree. As you know, the temperature of melting ice is invariably the same and equal to 0°C. At the same time, water from melting ice from the environment must absorb a relatively enormous amount of heat (80 cal/g).

We observe the same jump when water turns into steam. Without increasing the temperature of boiling water, which will invariably (at a pressure of 1 atm.) be equal to 100°C, the water itself must absorb from the environment almost 7 times more heat than when ice melts, namely: 539 cal.

If steam turns into water or water turns into ice, then the same amount of heat in calories (539 and 80) must be released from the water and warm the environment, surrounding water. In water these values ​​are unusually high. For example, the latent heat of vaporization of water is almost 8 times greater, and the latent heat of fusion is 27 times greater than that of alcohol.

An even more surprising and no less unexpected property of water is the change in its density depending on changes in temperature. All substances (except bismuth) increase their volume and decrease density as the temperature increases. In the range from +4°C and above, water increases its volume and decreases density, like other substances, but starting from +4°C and below, right up to the freezing point of water, its density begins to fall again, and its volume expands, and in At the moment of freezing, a jump occurs, the volume of water expands by 1/11 of the volume of liquid water.

The exceptional significance of such an anomaly is quite clear to everyone. If this anomaly did not exist, the ice would not be able to float, reservoirs would freeze to the bottom in winter, which would be a disaster for everything living in the water. However, this property of water is not always pleasant for humans - freezing of water in water pipes leads to their rupture.

There are many other water anomalies, e.g. temperature coefficient The expansion of water in the range from 0 to 45°C increases with increasing pressure, but for other bodies it is usually the opposite. Thermal conductivity, dependence of dielectric constant on pressure, self-diffusion coefficient and many other properties are also anomalous.

The path to explaining these water anomalies lies in identifying the features of the structures formed by water molecules in various aggregate (phase) states associated with temperatures, pressures and other conditions in which water is found. Unfortunately, there is no unity of views on this issue. Most modern researchers are of the opinion of a two-structure model of water, according to which water is a mixture of: loose ice-like and densely packed structures.

Behavior of water in nature different conditions pressure, temperature, electromagnetic fields, and especially differences in electrical potentials and much more, are mysterious, especially since natural water is not chemically pure substance, it contains many substances in solution (essentially all the elements periodic table), and in different concentrations. This mystery is especially great for the great depths of the Earth's lithosphere, where high pressures and temperatures occur. But even if we take “pure” water and see how some of its properties change at relatively high pressures and temperatures, then, for example, for density we get the following values, g/cm 3: at 100°C and 100 atm., and also at 1000°C and 10,000 atm. it will be the same and close to 1; at 1000°C and 100 atm. – 0.017; at 800°C and 2500 atm. - 0.5; at 770°C and 13,000 atm. – 1.7, and the electrical conductivity of such water is equal to the electrical conductivity of pentanormal hydrochloric acid. For brines that dominate the depths of the lithosphere, all these values ​​will change.

The properties of water also change under the influence of electric fields of different frequencies. At the same time, the intensity of light in water weakens, this is due to the absorption of its rays. Further, the rate of water evaporation changes by approximately 15%.

Generally in lately An increasing number of researchers, based on field and laboratory observations, are coming to the conclusion about the significant role of the difference in natural electrical potentials for the physical and chemical characteristics of natural waters. Even in the near-surface zones of the lithosphere with relatively weak electrical potentials, the potential difference causes both the movement of the water itself and the cations and anions dissolved in it in mutual opposite directions. Some scientists have observed the emergence of electrical potentials (and their differences) at the contact between water and ice, as well as in sulfide deposits. At greater depths of the lithosphere, one should expect more significant potential differences between different rocks and different solutions.

Everything that we have said so far about the variety of varieties of water concerned pure water, without any impurities. But chemically pure water cannot exist anywhere in nature. Even artificially distilled water after repeated distillation will contain dissolved carbon dioxide, nitrogen, oxygen, as well as a small part of the substance from which the vessel in which it is located is made.

Thus, it is very difficult to obtain almost pure water even artificially, although similar experience at the beginning of the 20th century and was carried out by the German physicist F. Kohlrausch. He obtained it in a completely insignificant volume and for a few seconds, during which it was possible to determine its electrical conductivity, absolutely clean water.

All water in nature, including snow, ice and rain, is a solution of various substances in the form of ions of neutral molecules, small and large suspensions, living beings (from bacteria to large animals) and their waste products.

3. Water cycle in nature

The human body is penetrated by millions of blood vessels. Large arteries and veins connect the main organs of the body with each other, smaller ones intertwine them on all sides, and the finest capillaries reach almost every individual cell. Whether you are digging a hole, sitting in class or sleeping blissfully, blood continuously flows through them, connecting the brain and stomach, kidneys and liver, eyes and muscles into a single system of the human body. What is blood needed for?

Blood carries oxygen from your lungs and nutrients from your stomach to every cell in your body. Blood collects waste products from all, even the most secluded corners of the body, freeing it from carbon dioxide and other unnecessary, including dangerous, substances. Blood carries special substances throughout the body - hormones, which regulate and coordinate the work of different organs. In other words, blood connects different parts of the body into a single system, into a coherent and efficient organism.

Our planet also has a circulatory system. The blood of the Earth is water, and the blood vessels are rivers, rivulets, streams and lakes. Water on Earth plays the same role as blood in the human body, and as scientists recently noted, the structure river network very similar to the structure of the human circulatory system. “The charioteer of nature” - this is what the great Leonardo da Vinci called water, it is she who passes from soil to plants, from plants to the atmosphere, flowing down rivers from continents to the oceans and returning back with air currents, connecting various components of nature with each other, transforming them into a single geographical system. Water does not simply pass from one natural component to another. Like blood, it carries with it a huge amount of chemicals, exporting them from the soil to plants, from land to lakes and oceans, from the atmosphere to land. All plants can consume nutrients contained in the soil only with water, where they are in a dissolved state. If it were not for the influx of water from the soil into the plants, all herbs, even those growing in the richest soils, would die “of hunger,” like a merchant dying of hunger on a chest of gold. Water supplies nutrients to the inhabitants of rivers, lakes and seas. Streams, flowing merrily from fields and meadows during the spring melting of snow or after summer rains, collect chemicals stored in the soil along the way and bring them to the inhabitants of reservoirs and the sea, thereby connecting the land and water areas of our planet. The richest “table” is formed in those places where rivers carrying nutrients flow into lakes and seas. Therefore, such areas of the coast - estuaries - are distinguished by a riot of underwater life. And who removes the waste generated as a result of the life activity of various geographical systems? Again, water, and as an accelerator it works much better than the human circulatory system, which only partially performs this function. The purifying role of water is especially important now, when people are poisoning the environment with waste from cities, industrial and agricultural enterprises. The body of an adult contains approximately 5-6 kg of blood, most of which continuously circulates between different parts of the body. How much water does the life of our world need?

All water on earth that is not part of rocks is united by the concept of “hydrosphere”. Its weight is so great that it is usually measured not in kilograms or tons, but in cubic kilometers. One cubic kilometer is a cube with each edge measuring 1 km, constantly occupied by water. The weight of 1 kg 3 of water is equal to 1 billion tons. The entire earth contains 1.5 billion km 3 of water.

But, unfortunately, everything is not so simple. The fact is that 94% of this volume consists of the waters of the world’s oceans, which are not suitable for most economic purposes. Only 6% is land water, of which only 1/3 is fresh, i.e. only 2% of the total volume of the hydrosphere. The bulk of this fresh water is concentrated in glaciers. Significantly less of them are contained under the earth's surface (in shallow underground water horizons, in underground lakes, in soils), as well as in atmospheric vapors. The share of rivers, from which people mainly take water, is very small - 1.2 thousand km 3. The total volume of water simultaneously contained in living organisms is absolutely insignificant. So there is not so much water on our planet that humans and other living organisms can consume.

The source of water movement on Earth is the energy of the Sun. The sun's rays hit the surface of the Earth, transfer their energy to water and heat it, turning it into steam. On average every hour from 1 square meter water surface 1 kilogram of water evaporates. Theoretically, within 1000 years, almost all the water in the world's oceans can be in the form of steam.

The planet's natural steam engine creates huge volumes of atmospheric water, transports them over considerable distances and pours them onto the Earth in the form of precipitation. Atmospheric precipitation falls into rivers, which carry their waters into the World Ocean. This is how the water cycle occurs in nature.

There are small and great gyre. The small cycle is associated with the precipitation of atmospheric water in the form of precipitation into the World Ocean, the large cycle - in the form of precipitation on land.

Every year about 100 thousand cubic kilometers of water falls on land. These waters replenish rivers and lakes and penetrate rocks. Some of this water returns to the seas and oceans, some evaporates, and some is used by plants and living organisms for nutrition and growth, i.e. to deliver nutrients from the soil to cells, and also to regulate their temperature. In this case, huge amounts of water evaporate into the atmosphere.

The bulk of water is concentrated in the oceans. The water evaporating from its surface provides life-giving moisture to natural and artificial land ecosystems; the closer the area is to the ocean, the more precipitation falls. The land constantly returns water to the ocean, some of the water evaporates, especially by forests, and some is collected by rivers, which receive rain and snow water after they melt.

The exchange of moisture between the ocean and land requires a very large amount of energy: up to 1/3 of what the Earth receives from the Sun is spent on this. Before the development of civilization, the water cycle in the biosphere was in equilibrium; the ocean received as much water from rivers as it consumed during its evaporation. If the climate did not change, the rivers would not become shallow and the water level in the lakes would not decrease.

But with the development of civilization, this cycle began to be disrupted; as a result of watering agricultural crops, evaporation from land increased. Rivers in the southern regions have become shallow, pollution of the World Ocean and the appearance of an oil film on its surface have reduced the amount of water evaporated by the ocean.

4. Water quality

Water quality is a set of chemical, physical, biological and bacteriological indicators that determine the suitability of water for use in industry, agriculture and everyday life.

According to the World Health Organization (WHO), about 5 million people die every year due to poor water quality. Infectious morbidity in the population associated with water supply reaches 500 million cases per year. This gave reason to call the problem of water supply with good quality water in sufficient quantities problem number one.

In nature, water never occurs in chemical form. pure connection. Possessing the properties of a universal solvent, it constantly carries large number various elements and compounds, the composition and ratio of which is determined by the conditions of water formation and the composition of aquifers. Atmospheric water absorbs carbon dioxide from the ground and becomes capable of dissolving mineral salts along the way.

Passing through rocks, water acquires properties characteristic of them. So, when passing through calcareous rocks, water becomes calcareous, and through dolomite rocks - magnesium. Passing through rock salt and gypsum, the water is saturated with sulfate and chloride salts and becomes mineral.

After building a well, or any other source of water supply, it is necessary to conduct research on the quality and composition of the water to determine its suitability for use and consumption. We must remember that economically drinking water refers to food products and its indicators must meet in accordance with the Law of the Russian Federation “On the Sanitary and Epidemic Welfare of the Population” of April 19, 1991, sanitary rules SanPiN 4630-88 and the requirements of GOST 2874-82 “Drinking water”.

Water quality is characterized by its physical, chemical and bacteriological properties.

Physical properties include its temperature, color, turbidity, taste and smell.

The temperature of water from wells should be 7...12°C. Water having more high temperature, loses its refreshing properties. Temperatures below 5°C are considered harmful to human health and lead to colds.

Chromaticity refers to its color and is expressed in degrees on the platinum-cobalt scale.

Turbidity is determined by the content of suspended particles in water and is expressed in milligrams per liter (mg/l). Water underground sources has low turbidity.

The presence of organic substances in water sharply worsens its physical (organoleptic) characteristics, causing various kinds of odors (earthy, putrefactive, fishy, ​​swampy, pharmaceutical, camphorous, oil smell, chlorophenolic, etc.), increases color, foaming, and has an adverse effect for humans and animals.

It was found that minor changes physical properties water reduces the secretion of gastric juice, and pleasant taste sensations increase visual acuity and heart rate (unpleasant ones - reduce).

The chemical properties of water are characterized by the following indicators: active reaction, hardness, oxidability, content of dissolved salts.

The active reaction of water is determined by the concentration of hydrogen ions. It is usually expressed in terms of pH. At pH=7 the environment is neutral; at pH<7 среда кислая, при pH>7 alkaline environment.

The hardness of water is determined by the content of calcium and magnesium salts in it. It is expressed in milligram equivalents per liter (mg·eq/L). Water from underground sources has high hardness, while water from surface sources has relatively low hardness (3-6 mEq/l).

Hard water contains a lot mineral salts, from which scale - rock salt - forms on the walls of dishes, boilers and other units. Hard water is destructive and unsuitable for water supply systems. In such water, tea does not brew well, soap does not dissolve well, and vegetables, especially legumes, are hardly cooked. Soft water should have a hardness of no more than 10 mEq/l.

In recent years, it has been suggested that water with a low content of hardness salts contributes to the development of cardiovascular diseases.

Oxidability is determined by the content of dissolved organic substances in water and can serve as an indicator of contamination of the source with wastewater. For wells, wastewater that contains proteins, fats, carbohydrates, organic acids, ethers, alcohols, phenols, oil, etc.

The content of dissolved salts in water (mg/l) is characterized by dense (dry) sediment. Water from surface sources has less dense sediment than water from underground sources, i.e. contains less dissolved salts. The limit of mineralization of drinking water (dry residue) of 1000 mg/l was at one time established on an organoleptic basis. Waters with a high salt content have a brackish or bitter taste. They are allowed to be contained in water at the sensation threshold level: 350 mg/l for chlorides and 500 mg/l for sulfates. The lower limit of mineralization, at which the body's homeostasis is maintained by adaptive reactions, is a dry residue of 100 mg/l, the optimal level of mineralization is 200-400 mg/l. In this case, the minimum calcium content must be at least 25 mg/l, magnesium - 10 mg/l.

The degree of bacteriological contamination of water is determined by the number of bacteria contained in 1 cubic cm of water and should be up to 100. Water from surface sources contains bacteria introduced by sewage and rainwater, animals, etc. Water from underground artesian springs is usually not contaminated with bacteria.

There are pathogenic (disease-causing) and saprophytic bacteria. To assess the contamination of water with pathogenic bacteria, the content of E. coli in it is determined. Bacterial contamination is measured by coli titer and coli index. Coli titer - the volume of water containing one E. coli must be at least 300. Coli index - the number of E. coli contained in 1 liter of water must be up to 3.

5. Impact of water pollution on human health

Technical civilization cannot exist without the use of technological aqueous solutions and clean water. Every day, millions of cubic meters of various solutions are prepared around the world from pre-purified water and chemical reagents obtained from natural mineral raw materials.

Every day, millions of cubic meters of waste technological solutions are purified before being discharged into sewers, trying to free them from harmful substances. However, returning water to its original state after purification is fundamentally impossible due to thermodynamic limitations.

As a result of such human activities, dangerous tendencies have emerged in nature. Fresh water reserves in the world are steadily decreasing due to its ever-increasing mineralization. In recent decades, the proportion of heavy metal ions in the total salt content in natural waters has sharply increased. The concentration of dissolved pesticides, fertilizers, surfactants, and petroleum products is also constantly increasing.

People need to expend more and more effort and energy to obtain water suitable for their own drinking, agriculture, powering boilers of thermal and power plants, and the production of various products: cars, furniture, fabrics, medicines, household appliances.

All impurities in natural waters are conventionally divided into insoluble and soluble. One part of insoluble impurities is present in water in the form of suspensions and emulsions, consisting of products of soil erosion and washout from the surface of the earth. These impurities are suspended and precipitate relatively easily.

Another part of insoluble impurities (organic and mineral colloidal particles– humus, viruses, etc.) are less prone to precipitation, and it is quite difficult to separate these impurities from water.

Soluble impurities can be contained in the form of molecular solutions (which also includes dissolved gases) or in the form of compounds dissociated into ions, so the separation of these substances also has its own specifics.

The unique structure of water determines its versatility as a solvent. The entire periodic system can be found in natural waters. The constantly increasing anthropogenic load on the environment has led to the fact that at present the self-purification processes in reservoirs are so inhibited that the reservoir often cannot cope with the processing of those harmful substances that enter it with sewage, household, and storm drains. When impurities combine, toxins interact, resulting in the formation of new ones, possibly more toxic than starting materials. It is difficult to even guess, much less take into account what compounds are present in the water.

Depending on the degree of pollution, water bodies are divided into seven classes. The degree of pollution - water quality - is determined by a complex indicator called the water pollution index (WPI), which is calculated using a certain methodology based on data on the content of oil products, copper, chlorides and sulfides and other impurities in water.

Below are the WPI values ​​depending on the class of water:

1st class – very clean water (less than 0.3)

2nd class – clean water (up to 1)

3rd class – moderately polluted (1…2.5)

4th class – polluted (2.5…4)

5th grade – dirty (4…6)

6th grade – very dirty (6…10)

7th grade – extremely dirty (more than 10)

Reservoirs of the first two classes do not exist in Russia at all. If we're lucky, we drink water from class 3 reservoirs.

Underground water sources are characterized by increased mineralization, hardness, and iron content.

When analyzing the main pollutants special attention should be addressed to heavy metals. They accumulate in the liver, kidneys, skeletal system, affect the nervous system and reproductive function, and can cause long-term effects that can manifest themselves in lesions cardiovascular system. A number of metals are carcinogenic. Mercury, lead, arsenic, and manganese have an adverse effect on the offspring.

Use in agriculture leads to contamination of drinking water supplies with chlorine and organophosphorus pesticides, which have an adverse effect on the functions of the liver, thyroid gland, immune system, and have mutagenic properties.

Petroleum products remain among the most dangerous water pollutants containing carcinogenic substances.

The constantly growing volume of production of synthetic surfactants (S.P.A.S.), used as detergents and various additives in household chemicals, the national economy, leads to the pollution of water bodies with these toxins. Existing treatment methods do not allow water to be removed from them during water treatment at the NFS. Moreover, thanks to surfactants, which act as a “tug” for a number of chemicals, contaminants overcome the barriers of water treatment facilities.

Surfactants, interacting with cells, contribute to the development of atherosclerosis; intensification of protein and carbohydrate metabolism, dysfunction of the liver, kidneys, immune and reproductive systems. With the combined presence of surfactants, metals, pesticides, and other substances, their toxicity increases.

We must not forget about the presence of microorganisms in water. Many intestinal infections, which belong to the group of infectious diseases caused by pathogenic microorganisms (for example, typhoid fever, dysentery, cholera, salmonellosis, viral hepatitis), are associated with the water factor.

According to the World Health Organization (WHO), water contains 13 thousand potentially toxic elements; 80% of diseases are transmitted by water; 25 million people die from them every year.

For human health adverse consequences when using contaminated water, as well as when coming into contact with it (bathing, washing, fishing etc.) appear either directly when drinking, or as a result of biological accumulation along long food chains type: water - plankton - fish - man or water - soil - plants - animals - man, etc.

6. Modern methods of water purification

Water treatment is the process of removing natural, domestic and industrial pollution for the purpose of obtaining water suitable for drinking or technical use.

Disinfection. The main goal of water treatment is to produce bacterially safe water. The most common way to disinfect water is to introduce chlorine into it, a strong oxidizing agent that is added to water in the form of a gas or a concentrated aqueous solution. The effectiveness of chlorine treatment depends on a number of factors, including pH (a measure of the acidity or alkalinity of water), treatment time, temperature, and the presence of organic substances that react with chlorine. Small quantity free chlorine is left in the water in case contaminants enter the consumer water supply network. Since domestic water use discharges many coliform bacteria into drains, the detection of these bacteria serves as an indicator of household contamination (coliform index).

Turbidity. Turbidity and color are eliminated by adding a chemically active substance to the water and then allowing it to settle. The added substance promotes the growth of small particles and their transformation into larger ones until, under the influence of their own weight, they begin to settle. This forced sedimentation process takes 1–2 hours. This sediment formation process is called chemical coagulation. The chemically active substances used are mainly compounds that form aluminum and ferric ions in an aqueous solution (aluminum sulfate and ferric chloride or sulfate).

Water and smell. Typical sources of taste and odor from natural, household and industrial waters– microorganisms such as algae in surface waters and sulfides in oxygen-poor groundwater. Connections having bad taste and odor are usually removed by adding activated carbon to water and subsequent sedimentation. It is also possible to subject such compounds to oxidation, such as with chlorine or ozone.

Filtration. At a water treatment plant, where chemicals are added to the water and settled to remove impurities, the water is also passed through sand to be filtered. Water and coagulant chemicals are thoroughly and intensively mixed. After about 30 minutes, water with enlarged particles of impurities is launched into a sedimentation unit, where most of the impurities are precipitated and removed from the water; this process takes about 2 hours. Clarified water is sent to settling tanks, where it is filtered through layers of sand and gravel and passes through the bottom. The bottom base not only serves as a support for layers of gravel and sand, but also allows water to pass through, which is periodically used to wash the filter layers of sediment left behind by the water being purified. Filtered water is stored in tanks or pumped into the water supply network after final chlorination.

Rigidity. The problem of reducing water hardness can be partially solved by using synthetic detergents. Using chemical coagulation or ion exchange, hardness-causing impurities (mainly calcium and magnesium bicarbonates) are partially or completely removed. This process is called water softening.

In chemical coagulation systems, lime is added to water to soften it, which reacts with bicarbonates, turning them into carbonates, which precipitate. The sediment is removed by sedimentation and subsequent sand filtration.

Ion (more precisely, cation) exchange for softening consists of replacing hardness ions, calcium and magnesium, with a non-hardness ion, sodium. Home water softening systems are based on this principle. Using ion exchange, it is possible, in principle, to replace all cations in water with hydrogen, and all anions with oxygen. The result is clean water. This process is called desalting.

Aeration. There may be other chemical elements or compounds dissolved or suspended in water that affect its quality. Iron is extracted by oxidation with atmospheric oxygen and removal of the insoluble compound by sedimentation or filtration. For magnesium, along with aeration, contact with the adsorbent is required. If iron or magnesium is present in water in the form of organic complexes, oxidation and chemical coagulation should be used.

Fluoridation. Fluoride is often added to tap water for reasons unrelated to basic drinking water safety and cleanliness standards. The presence of fluoride in water in very low concentrations slows down the formation of dental caries, especially in children.

Also, modern urban planning projects provide for the construction of special treatment facilities in places where wastewater is discharged.

To protect the source of domestic drinking water supply, a special territory is allocated, called a sanitary protection zone. A special regime is established in this territory, significantly limiting the possibility of water pollution, reducing its quality at the point of water intake, and reducing the flow rate of the water source.

However, sanitary and technical measures that are carried out in places of water intake, as well as places of wastewater discharge, are not enough for the environmental protection of reservoirs.

It is very important to maintain the ability of reservoirs to self-purify. One of the processes of self-purification of a reservoir is the sedimentation of insoluble substances. The self-purification of reservoirs is influenced by factors such as the degree of dilution of contaminants, flow speed, and water temperature. Organic matter in wastewater gradually decomposes under the influence of oxygen. Biological need The oxygen content of a reservoir (BOD) is expressed by the weight amount of oxygen dissolved in water, consumed in the processes of biological decomposition of organic substances. The BOD value ranges from 1 mg/L for clean surface water to 500 mg/L for untreated domestic wastewater. When dissolved oxygen resources are depleted, the process of self-purification of the reservoir stops and unfavorable anaerobic transformations begin to predominate in it. The ability of a reservoir to self-purify is also ensured by the combined activity of the bacteria, algae, aquatic plants, and mollusks inhabiting them. If the water temperature is favorable for their life, then the self-purification of the reservoir proceeds faster.

Three main methods of wastewater treatment are practiced.

The first has been around for a long time and is the most economical: discharging wastewater into large watercourses, where it is diluted with fresh running water, aerated and neutralized naturally. Obviously, this method does not meet modern conditions.

The second method is largely based on the same natural processes as the first, and consists of removing and reducing the content of solid and organic substances by mechanical, biological and by chemical means. It is mainly used in municipal wastewater treatment plants, which rarely have the equipment to process industrial and agricultural wastewater.

The third method is widely known and quite common, which consists of reducing the volume of wastewater by changing technological processes; for example, as a result of recycling materials or using natural methods pest control instead of pesticides, etc.

Although many industrial enterprises are now trying to clean up their wastewater or make the production cycle closed, and the production of pesticides and other toxic substances is prohibited, the most radical and quick solution The problem of water pollution will be the construction of additional and more modern treatment facilities.

Primary (mechanical) cleaning. Typically, grates or sieves are installed along the wastewater flow path to trap floating objects and suspended particles. Sand and other coarse inorganic particles are then deposited in sand traps with sloping bottoms or captured in sieves. Oils and fats are removed from the surface of the water using special devices (oil traps, grease traps, etc.). For some time, wastewater is transferred to settling tanks to settle fine particles. Free-floating floc particles are settled by adding chemical coagulants. The sludge thus obtained, 70% consisting of organic substances, is passed through a special reinforced concrete tank - a methane tank, in which it is processed by anaerobic bacteria. As a result, liquid and gaseous methane, carbon dioxide, and mineral solid particles are formed. In the absence of a digester, solid waste is buried, dumped in landfills, burned (which leads to air pollution), or dried and used as humus or fertilizer.

Secondary treatment carried out mainly biological methods. Since at the first stage organic matter are not removed, at the next stage aerobic bacteria are used to decompose suspended and dissolved organic matter. The main task is to bring the wastewater into contact with as many bacteria as possible under conditions of good aeration, since the bacteria must be able to consume sufficient quantity dissolved oxygen. Wastewater is passed through various filters - sand, crushed stone, gravel, expanded clay or synthetic polymers(in this case, the same effect is achieved as in the process of natural purification in a riverbed stream that has covered a distance of several kilometers).

Bacteria form a film on the surface of the filter material and decompose organic matter in the wastewater as it passes through the filter, thereby reducing the BOD by more than 90%. This is the so-called bacterial filters. A 98% reduction in BOD is achieved in aeration tanks, in which natural oxidation processes are accelerated due to forced aeration of wastewater and its mixing with activated sludge. Activated sludge is formed in settling tanks from particles suspended in waste liquid, not retained during preliminary treatment and adsorbed by colloidal substances with microorganisms multiplying in them.

Another method of secondary purification is long-term settling of water in special ponds or lagoons (irrigation fields or filtration fields), where algae consume carbon dioxide and release oxygen necessary for the decomposition of organic matter. In this case, BOD is reduced by 40–70%, but certain temperature conditions and sunlight are required.

Tertiary treatment. Wastewater that has undergone primary and secondary treatment still contains dissolved substances that make it practically unsuitable for any use other than irrigation. Therefore, more advanced cleaning methods have been developed and tested to remove remaining contaminants. Some of these methods are used in installations that purify drinking water from reservoirs. Slowly decomposing organic compounds such as pesticides and phosphates are removed by filtering the treated wastewater through activated (powdered) charcoal, or by adding coagulants to promote agglomeration of fine particles and sedimentation of the resulting flocs, or by treating with such reagents that provide oxidation.

Dissolved inorganic substances are removed by ion exchange (dissolved salt and metal ions); chemical precipitation (calcium and magnesium salts, which form deposits on the inner walls of boilers, tanks and pipes), softening the water; changing the osmotic pressure for enhanced filtration of water through a membrane, which retains concentrated solutions of nutrients - nitrates, phosphates, etc.; removal of nitrogen by air flow when wastewater passes through an ammonia desorption column; and other methods. There are only a few enterprises in the world that can carry out complete wastewater treatment.

Conclusion

The problem of pollution of land waters (rivers, lakes, reservoirs, groundwater) is closely related to the problem of security fresh water Therefore, special attention is paid to observations and control of the level of pollution of water bodies. The Freshwater Pollution Control Service is part of national systems environmental pollution monitoring. The main purpose of the service for observing and monitoring the level of land water pollution is to obtain information on water quality necessary for the implementation of measures both for water protection and rational use water resources. The service solves the problems of monitoring the level of water pollution by physical, chemical and hydrobiological indicators and the problem of studying the dynamics of pollutants for forecasting the pollution of water bodies. An important task of monitoring is to study the processes of self-purification of water bodies and the accumulation of pollutants in bottom sediments and to study the patterns of the removal of substances into water bodies (seas, lakes, reservoirs).

Modern monitoring of the state of the Earth's hydrosphere is based on the use the latest achievements science and technology. When equipping observational ground platforms and automatic stations in the World Ocean, radar stations and aircraft in the atmosphere, microprocessors are widely used for measuring and primary data processing. The process of monitoring natural water pollution develops quantitative approaches to identify key variables and parameters necessary to understand the factors determining changes in the aquatic environment. Processing and synthesis of information coming from a stationary network of ground-based and near-surface observations, from Earth satellites, expeditionary studies of the World Ocean and hard-to-reach areas of the earth's land are carried out using electronic computers and on the basis of archives of created data banks.

The logic of the development of life on Earth determines human activity as main factor, and the biosphere can exist without man, but man cannot exist without the biosphere. A factor in the existence of the biosphere is clean water. Future generations will not forgive us for depriving them of the opportunity to enjoy pristine nature. Preserving the harmony of man and nature is the main task facing the present generation. This requires a change in many previously established ideas about the comparison of human values. Every person needs to develop ecological consciousness”, which will determine the choice of technology options, the construction of enterprises and the use of natural resources.

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Currently, the problem of pollution of water bodies (rivers, lakes, seas, groundwater, etc.) is the most pressing, because Everyone knows the expression “water is life.” A person cannot live without water for more than three days, but even understanding the importance of the role of water in his life, he still continues to harshly exploit water bodies, irreversibly changing them natural mode discharges and waste. The tissues of living organisms consist of 70% water. There is a lot of water on Earth, but 97% is salt water of the oceans and seas, and only 3% is fresh. Of this, three quarters are almost inaccessible to living organisms, since this water is “conserved” in mountain glaciers and polar caps (glaciers of the Arctic and Antarctic).

Water is the basis of life on Earth and its homeland. Unfortunately, the abundance of water is only apparent; in reality, the hydrosphere is the thinnest shell of the Earth, because water in all its states and in all spheres accounts for less than 0.001 of the mass of the planet. Nature is designed in such a way that water is constantly renewed in a single hydrological cycle, and the protection of water resources should be carried out in the very process of water use by influencing individual parts of the water cycle. Before the development of civilization, the water cycle in the biosphere was in equilibrium; the ocean received as much water from rivers as it consumed during its evaporation. If the climate did not change, then the rivers did not become shallow and the water level in the lakes did not decrease. With the development of civilization, this cycle began to be disrupted; as a result of watering agricultural crops, evaporation from land increased. The rivers of the southern regions became shallow, the pollution of the oceans and the appearance of an oil film on its surface reduced the amount of water evaporated by the ocean. All this worsens the water supply to the biosphere. Droughts are becoming more frequent. Moreover, she herself fresh water, which returns to the ocean and other bodies of water from land, is often polluted, and the water of many Russian rivers has become practically unsuitable for drinking.

A previously inexhaustible resource - fresh, clean water - is becoming exhaustible. Today, water suitable for drinking, industrial production and irrigation is in short supply in many areas of the world.

Demands for water are increasing from year to year. The main consumers of water are industry and agriculture. The industrial importance of water is very great, since almost all production processes require large quantities of it. The bulk of water in industry is used for energy production and cooling. For these purposes, water quality is not of great importance, therefore, the basis for reducing the water intensity of industrial production is water recycling, in which water once taken from the source is used repeatedly, thereby “increasing” the reserves of water resources and reducing their pollution. The largest “water consumers” among industrial sectors are ferrous metallurgy, chemistry, petrochemicals and thermal power engineering.

Main types of water pollution

Pollution of water resources refers to any changes in the physical, chemical and biological properties of water in reservoirs in connection with the discharge of liquid, solid and gaseous substances into them that cause or may create inconvenience, making the water of these reservoirs dangerous for use, causing damage to the national economy, health and public safety. Sources of pollution are recognized as objects from which discharge or otherwise enter water bodies of harmful substances that worsen the quality of surface waters, limit their use, and also negatively affect the condition of the bottom and coastal water bodies.

Pollution of surface and groundwater can be divided into the following types:

mechanical - an increase in the content of mechanical impurities, characteristic mainly superficial types pollution;

chemical - the presence of organic and inorganic substances toxic and non-toxic effects;

bacterial and biological - the presence of various pathogenic microorganisms, fungi and small algae in the water;

radioactive - the presence of radioactive substances in surface or underground waters;

thermal - release of heated water from thermal and nuclear power plants into reservoirs.

The main sources of pollution and clogging of water bodies are insufficiently treated wastewater from industrial and utility companies, large livestock complexes, production waste during the development of ore minerals; water from mines, mines, processing and rafting of timber; discharges from water and rail transport; waste from primary flax processing, pesticides, etc. Pollutants entering natural bodies of water lead to qualitative changes in water, which are mainly manifested in changes in the physical properties of water, in particular, the appearance of unpleasant odors, tastes, etc.); in changes in the chemical composition of water, in particular, the appearance of harmful substances in it, the presence of floating substances on the surface of the water and their deposition at the bottom of reservoirs.