Waste water pollutants. By physical condition. The impact of pollution on water bodies

Common data.

Wastewater - contaminated with household waste and industrial waste and removed from the territories of populated areas and industrial enterprises by sewerage systems. Wastewater also includes waters formed as a result of precipitation within the territories of settlements and industrial facilities. Organic substances contained in wastewater, getting into water bodies in significant quantities or accumulating in the soil, can quickly rot and worsen the sanitary condition of water bodies and the atmosphere, contributing to the spread of various diseases. Therefore, the issues of purification, neutralization and disposal of wastewater are an integral part of the problem of nature protection, improvement of the human environment and ensuring the sanitary improvement of cities and other populated areas.

Classification and composition of wastewater depending on the origin, composition and quality characteristics of pollution (impurities), wastewater is divided into 3 main categories:

household (household and fecal),

production (industrial),

atmospheric.

Domestic wastewater includes water removed from toilets, baths, showers, kitchens, baths, laundries, canteens, hospitals. They are polluted mainly with physiological waste and household waste. production sewage are waters used in various technological processes (for example, for washing raw materials and finished products, cooling thermal units, etc.), as well as waters pumped to the surface of the earth during mining.

Industrial wastewater from a number of industries is polluted mainly by production waste, which may contain toxic substances (for example, hydrocyanic acid, phenol, arsenic compounds, aniline, copper, lead, mercury salts, etc.), as well as substances containing radioactive elements; some wastes are of a certain value (as secondary raw materials). Depending on the amount of impurities, industrial wastewater. subdivided into:

contaminated, subjected to preliminary cleaning before release into the water (or before reuse),

conditionally clean (slightly contaminated), released into the reservoir (or reused in production) without treatment.

Atmospheric wastewater - rain and melt (formed as a result of melting ice and snow) water. According to the qualitative characteristics of pollution, this category also includes water from watering streets and green spaces. Atmospheric wastewater containing predominantly mineral contaminants is less hazardous in sanitary terms than domestic and industrial wastewater.

The degree of contamination with S. v. is estimated by the concentration of impurities, i.e., their mass per unit volume (in mg / l or g / m3).

The composition of household S. century. more or less uniform; the concentration of contaminants in them depends on the amount of tap water consumed (per inhabitant), i.e., on the rate of water consumption. Pollution of household S. in. usually subdivided into:

insoluble, forming large suspensions (in which particle sizes exceed 0.1 mm),

suspensions, emulsions and foams (in which particle sizes range from 0.1 mm to 0.1 µm),

colloidal (with particles ranging in size from 0.1 microns to 1 nm), soluble (in the form of molecularly dispersed particles less than 1 nm in size).

Distinguish pollution of domestic wastewater:

mineral,

organic,

biological.

Mineral contaminants include sand, slag particles, clay particles, solutions of mineral salts, acids, alkalis, and many other substances.

Organic contaminants are of plant and animal origin. Plant residues include the remains of plants, fruits, vegetables, paper, vegetable oils, etc. The main chemical element of plant pollution is carbon. Contaminants of animal origin are physiological excretions of people and animals, remains of animal tissues, adhesive substances, etc. They are characterized by a significant nitrogen content.

Biological contaminants include various microorganisms, yeasts and molds, small algae, bacteria, including pathogens (causative agents of typhoid, paratyphoid, dysentery, anthrax, etc.). This type of pollution is typical not only for domestic wastewater, but also for some types of industrial wastewater generated, for example, in meat processing plants, slaughterhouses, tanneries, biofactories, etc. According to their chemical composition, they are organic contaminants, but they are separated into a separate group due to the sanitary hazard they create when they enter water bodies.

In domestic wastewater, mineral substances contain about 42% (of the total amount of pollution), organic - about 58%; sedimented suspended solids make up 20%, suspensions - 20%, colloids - 10%, soluble substances - 50%. The amount of domestic wastewater depends mainly on the rate of wastewater disposal, which, in turn, is determined by the degree of improvement of buildings.

The composition and degree of contamination of industrial wastewater are very diverse and depend mainly on the nature of production and the conditions for using water in technological processes.

The amount of atmospheric water varies significantly depending on climatic conditions, terrain, the nature of urban development, the type of road surface, etc.

MPC standards for pollutants in wastewater discharged into sewerage in cities.

Ways and methods for determining the content of pollutants in wastewater:

Biochemical oxygen demand - measured by the device BOD - tester.

Suspended solids - determined by filtration through a membrane filter. Glass, quartz or porcelain, paper are not recommended due to hygroscopicity.

Nitrogen of ammonium salts - the method is based on the interaction of the ammonium ion with the Nessler reagent, resulting in the formation of mercuric iodide - ammonium yellow color:

NH 3 +2 (HgI 2 + 2 K) + 3 OH \u003d 3 HgI 2 + 7 KI + 3 H 2 O.

Sulfates - the method is based on the interaction of sulfate-oins with barium chloride, resulting in the formation of an insoluble precipitate, which is then weighed.

Nitrates - the method is based on the interaction of nitrates with sulfasalicylic acid with the formation of a yellow complex compound at pH = 9.5-10.5. Measurements are carried out at 440 nm.

Petroleum products are determined by the gravimetric method, pre-treatment of the test water with chloroform.

Chromium - the method is based on the interaction of chromate ions with diphenylcarbazide. As a result of the reaction, a compound is formed purple. Measurements are carried out at λ=540 nm.

Copper - the method is based on the interaction of Cu 2+ ions with sodium diethyldithiocarbonate in a weakly ammonia solution with the formation of copper diethyldithiocarbonate, colored yellow-brown.

Nickel - the method is based on the formation of a complex compound of nickel ions with dimethylglyoxin, colored brownish-red. Measurements are carried out at λ=440 nm.

Zinc - the method is based (at pH = 7.0 - 7.3) on the connection of zinc with sulfarsazene, colored yellow-orange. Measurements are carried out at λ = 490 nm.

Lead - the method is based on the combination of lead with sulfarsazen, colored yellow-orange. Measurements are carried out at λ=490 nm.

Phosphorus - the method is based on the interaction of ammonium molybdate with phosphates. A solution of stannous chloride is used as an indicator. Measurements are carried out on KFK - 2 at λ=690-720 nm.

Nitrites - the method is based on the interaction of nitrites with the Griess reagent with the formation of a yellow complex compound. Measurements are carried out at λ=440 nm.

Iron - the method is based on sulfasalicylic acid or its salts (sodium) form complex compounds with iron salts, and in a slightly acidic medium, sulfasalicylic acid reacts only with Fe +3 salts (red color), and weakly alkaline - with Fe +3 and Fe +2 salts ( yellow coloring). Pollution of the oceans. cleaning sewage watersLesson outline >> Ecology

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Wastewater

Cleaning of drains

Wastewater any water and precipitation, discharged into water bodies from the territories of industrial enterprises and populated areas, through the sewerage system or by gravity, the properties of which turned out to be deteriorated as a result of human activity.

1. Views

The drain is polluted- wastewater containing impurities in excess of MPC (maximum permissible concentration).

2. Classification

2.1. Behind the source of pollution

The nature and concentration of pollutants in wastewater depend on the source of pollution, therefore, the main types of wastewater are distinguished:

• Surface sewage ("Storm drains") - are formed due to rain, melt (snow, hail) and irrigation water. They are usually discharged through the storm sewer system. They are divided into rain and melt. Contaminated usually with suspended solids of organic and mineral origin, oil products, biogenic substances and heavy metals.
• Municipal (domestic and fecal) wastewater - are formed in residential premises, as well as in amenity premises at work (shower cabins, toilets), are discharged through the domestic sewerage system or through hot alloys. Contaminated mainly with street debris, detergents and excrement. Most of the weighted solids is cellulose in nature and organic contaminants include fatty acid, carbohydrates and proteins. The unpleasant smell of domestic wastewater is due to the decomposition of proteins under anaerobic conditions. They are formed from the use of water in kitchens, toilets and showers, baths, laundries, canteens, hospitals, as well as household water generated from washing rooms. They come from both residential and public buildings, and from household premises of industrial enterprises. By the nature of pollution, wastewater can be fecal, coming from toilets and contaminated mainly with physiological waste, human life comes in, and household waste, contaminated with various kinds of waste.

The composition of domestic wastewater is relatively constant and is characterized mainly by organic contaminants (about 60%) in an undissolved, colloidal and dissolved state, as well as various bacteria and microorganisms, including pathogens. .

• Agricultural wastewater - are divided into wastewater from livestock complexes and surface wastewater from fields. The first type of wastewater contains a large number of organic pollution, the second contains substances that are used as fertilizers and plant protection products against pests.
• Mine and mine wastewater - are formed in the process of mining and processing of minerals, therefore, they often have a high mineralization, an acid reaction of the environment, a large number of mine elements that are in dissolved and suspended forms.
• Industrial (production) wastewater - are formed in technological processes during the production or extraction of minerals, are discharged through an industrial or hot-alloy sewer system. Can't give any typical characteristic extremely diverse pollution of industrial wastewater, which are the remains of processed raw materials and reagents involved in the technological process. The most characteristic and dangerous pollution of industrial wastewater is extractive substances (mainly oil products), phenols, synthetic surfactants, heavy metals, important organic substances, including various pesticides. They are formed as a result of the use of water in technological processes of production. The composition and concentration of industrial (industrial) wastewater pollution are very diverse and depend on the type and technology of production, feedstock and various components that are present in the process. Industrial wastewater may contain organic, mineral, radioactive impurities, as well as harmful and toxic substances. Allocate polluted and conditionally clean industrial wastewater. An example of conditionally clean wastewater can be water used for cooling in heat exchangers.

2.2. By type of pollution

According to the type of pollution, industrial wastewater is divided into 3 groups:

• 1) water, pollution with mineral additives (products, production of mineral fertilizers, acids, building products, oil products, etc.);
• 2) water pollution with organic impurities (wastewater from chemical, petrochemical processing industries, polymer production, etc.);
• 3) wastewater is contaminated with mineral and organic impurities (oil, light, food industries, etc.) formed from rainfall or snowmelt and contains mainly mineral and, to a lesser extent, organic pollution.

Atmospheric wastewater generated on the territory of industrial enterprises containing waste from the respective enterprises. Removal and neutralization of atmospheric wastewater is also included in the tasks of sewerage services. A feature of these waters is the unevenness of their flow. So, in dry weather, they are absent, and during a downpour, their number is large.

The composition of wastewater is studied in order to most rationally determine the following conditions and circumstances: the choice of a wastewater treatment method; the possibility of recycling valuable substances contained in wastewater and sludge (fats, fertilizers, etc.) the possibility of using treated wastewater as a source of technical water supply.

Wastewater can be contaminated with mineral and organic matter.

Mineral contaminants include sand, clay, slag, solutions of mineral salts, acids and alkalis. Organic contaminants are of plant and animal origin. Vegetable origin - contain the remains of plants, fruits, cereals, vegetables, paper. From a chemical point of view, these contaminants mainly contain carbon in the form of fiber. Animal origin - containing physiological waste of people and animals, fatty substances, organic acids and others. The main chemical element of these pollutions is nitrogen in the form of protein substances. Wastewater, except for carbon and nitrogen, containing phosphorus, potassium, sulfur, sodium and other chemical compounds.

There are also so-called bacterial and biological contaminants, in wastewater are represented by various bacteria, yeasts and molds, small algae.

According to the physical state of the pollution contained in wastewater, it can be in the form of a solution, colloids, suspensions and undissolved impurities. Depending on the size of the particles, their density and the speed of the wastewater, undissolved substances can float to the surface, be in suspension in the water and settle to the bottom. .

2.3. By physical condition

According to the physical state of wastewater pollution are divided into:

• insoluble impurities in water in the form of large suspended particles (more than 0.1 mm in diameter) and in the form of a suspension, emulsion and foam (particles with a diameter of 0.1 mm to 0.1 microns);
• colloidal particles diameter from 0.1 to 0.001 microns;
• soluble particles located in water in the form of molecularly dispersed particles with a diameter of less than 0.001 microns.

2.4. The nature of the pollutant

By the nature of the pollutant, mineral, organic and biological wastewater pollution is distinguished.

Mineral pollution includes particles of sand, clay, ores, slags, solutions of mineral salts, acids and alkalis, mineral oils, metal ions and inorganic substances.

Organic pollution of plant origin (remains of plants, fruits and vegetables and cereals, paper, vegetable oils, etc.) and animal (physiological secretions of people and animals, remains of muscle and fatty tissues of animals, adhesive substances, etc.) origin. Organic pollution is characterized by a fairly significant content of carbon, nitrogen, hydrogen, phosphorus and sulfur.

Biological pollution is a variety of microorganisms (unicellular fungi, algae and bacteria), including pathogens. This type of pollution is characteristic mainly of domestic and some industrial wastewater (runoff from livestock farms, tanneries, slaughterhouses, wool washes, biofactories, etc.). According to its chemical composition, this is an organic pollution, but they are distinguished into a separate group due to the special interaction with pollution of other types.

3. Composition

To determine the composition of wastewater, a large number of various analyzes are required - chemical, physico-chemical, sanitary-bacteriological. The main tasks to be solved on the basis of analyzes are:

• assessment of the sanitary and toxicological state of wastewater;
• determining the suitability of wastewater for a specific type of consumption, the degree and nature of wastewater pollution;
• search for a method of water purification, as well as the definition of methods for managing wastewater treatment processes and monitoring the operation of facilities;
• evaluation of the performance of individual structures and technological scheme wastewater treatment in general;
• control of the state of the reservoir.

4. Cleaning

4.1. Wastewater Treatment Methods

Industrial wastewater treatment is carried out by mechanical, physico-chemical, biological, thermal methods. Mechanical methods are used mainly as preliminary. These include the following methods: sedimentation, filtration, centrifugation. Physicochemical cleaning methods include coagulation, flocculation, sorption, flotation, extraction, evaporation, ion exchange, as well as electrocoagulation, electroflotation.

The biological method is used to treat wastewater from organic substances, heavy metal ions, for example, from chromium ions with the help of bacteria called dechromaticans, and some inorganic substances (H2, N2, NH3). The process is based on the mineralization of organic substances to simple mineral compounds that are in water both in a dissolved state and in a finely dispersed undissolved and colloidal state, with the help of special microorganisms. Anaerobic (without the participation of oxygen) and aerobic (with the participation of oxygen) methods of biochemical purification are known.

Thermal methods are used to treat highly mineralized wastewater containing calcium, magnesium salts, and organic impurities. Purified water is obtained mainly by evaporation in special installations. In some cases, the fire method is used, in which wastewater is sprayed directly into hot gases. At the same time, water completely evaporates, and organic impurities burn out, mineral substances turn into solid or molten particles, which are then captured.

New methods of industrial wastewater treatment include treatment of wastewater in magnetic and electric fields; dispersion of impurities contained in wastewater; membrane (ultrafiltration, reverse osmosis, microfiltration, evaporation through membranes, dialysis, electrodialysis).

Water pollution refers to any change in the physical, chemical and biological properties water in reservoirs in connection with the discharge of liquid, solid and gaseous substances into them, which cause or may create inconvenience, making the water of these reservoirs dangerous for use, causing damage to the national economy, health and safety of the population.

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

• 1. mechanical- Mechanical pollution is characterized by the ingress of various mechanical impurities into the water - sand, sludge, silt, etc. Mechanical impurities can significantly worsen the organoleptic characteristics and quality of water, and also adversely affect the living conditions of fish and the state of ecosystems. Thermal pollution is associated with an increase in water temperature as a result of mixing with more heated surface or process waters, resulting in a change in the gas and chemical composition of water, the reproduction of anaerobic bacteria, an increase in the number of hydrobionts and the release of toxic gases - hydrogen sulfide and methane. At the same time, there is a "bloom" of water, as well as an accelerated development of microflora and microfauna, which contributes to the development of other types of pollution.
• 2. Chemical- Chemical pollution is a change in the natural chemical properties of water due to an increase in the content of harmful impurities in it, both inorganic (mineral salts, acids, alkalis, clay particles) and organic nature (oil and oil products, organic residues, surfactants, pesticides).
• 3. Bacterial and biological- Wastewater contains big number microorganisms, including disease-causing (pathogenic) bacteria, which makes this water hazardous in sanitary terms. In domestic wastewater, there are typhoid bacteria, dysentery and other pathogens of gastrointestinal diseases, as well as helminth eggs (worms) that enter wastewater with human and animal excretions.
• 4. radioactive- Radioactive substances entering surface and underground waters can be of natural and artificial origin. The presence of natural radioactive substances in water is due to its contact with minerals containing radioactive isotopes (U238, Pa226, Th232), as well as interaction with the atmosphere, from which C14, Be10, H3 enter the water. The degree of radioactive contamination of water in this case is usually small.
• 5. Thermal- type of physical (usually anthropogenic) pollution environment, characterized by an increase in temperature above the natural level. The main sources of thermal pollution are emissions of heated exhaust gases and air into the atmosphere, and the discharge of heated wastewater into water bodies.

The main sources of pollution and clogging of water bodies are insufficiently treated wastewater from industrial and municipal enterprises, large livestock complexes, production waste from the development of ore minerals; water mines, mines, processing and alloying of timber; discharges of water and railway transport; flax primary processing waste, pesticides, etc.

Pollutants entering natural water bodies lead to qualitative changes water, which are mainly manifested in a change in the physical properties of water, in particular, the appearance of unpleasant odors, the appearance of harmful substances in it, substances on the surface of the water and their deposition at the bottom of reservoirs.

Industrial wastewater is polluted mainly by industrial waste and emissions. Their quantitative and qualitative composition is diverse and depends on the industry, its technological processes. They are divided into two main groups: containing inorganic impurities, toxic, and containing poisons.

The first group includes wastewater from soda, sulfate, nitrogen-fertilizer plants, processing plants for lead, zinc, nickel ores, etc., which contain acids, alkalis, heavy metal ions, etc. Wastewater from this group mainly changes physical properties water.

Wastewater of the second group is discharged by oil refineries, petrochemical plants, organic synthesis enterprises, coke-chemical plants, etc. The wastewater contains various petroleum products, ammonia, aldehydes, resins, phenols and other harmful substances. The harmful effect of wastewater of this group lies mainly in oxidative processes, as a result of which the oxygen content in water decreases, the biochemical demand for it increases, and the organoleptic indicators of water deteriorate.

Phenol is a rather harmful pollutant of industrial waters. It is found in the wastewater of many petrochemical plants. At the same time, the biological processes of reservoirs, the process of their self-purification, are sharply reduced, the water acquires a specific smell of carbolic acid.

chemical treatment for binding and precipitation nutrients or destruction of algae;

violation of stratification and reaeration;

phytomass collection and biomanipulation.

Preventive methods used to prevent eutrophication:

control of nutrient discharge;

removal of nutrients from wastewater;

use of preliminary settling tanks;

strategic restructuring of water management in the basin.

17 POLLUTION FROM HOUSEHOLD WASTEWATER

The oldest type of water pollution is direct human waste. In terms of dry matter, each adult "produces" about 20 kg of organic matter, 5 kg of nitrogen and 1 kg of phosphorus per year. Initially, this waste was directly used as fertilizer, then the first earthen latrines appeared. Part of the waste inevitably ended up in sources of drinking water. That is why large cities already in antiquity began to build water pipes from sources quite remote from crowded places.

With the advent of water closets, the idea of ​​a simple solution to the problem arose again - dilution of waste and removing it from the place of discharge. The volumes, and then the composition of wastewater to be treated, have changed significantly. Domestic sewage is currently coming not only from residential buildings, but also from hospitals, canteens, laundries, small industrial enterprises, etc. Modern household wastewater, in addition to easily oxidizable organic substances and biogenic elements, contains many substances used in everyday life: detergents and surfactants, chemicals, medications etc.

Easily oxidizable organic substances entering watercourses and reservoirs undergo chemical and microbiological oxidation there. To measure the content of organic substances in water, it is customary to use the value of biochemical oxygen consumption for 5 days. (BOD5 , BOD5 - Biochemical Oxygen Demand). It is determined by the difference in the oxygen content in water during sampling and after five days of incubation without oxygen. BOD5, reflecting the content of easily oxidizable organic matter in water, is a universal indicator using

which can compare the degree of pollution from different sources. Thus, in table 20, pollution from enterprises of various profiles is expressed in equivalents of pollution from people.

Table 20 Organic pollution of industrial wastewater in household wastewater equivalents

Consequences of pollution from domestic wastewater

Easily oxidizable organic matter, contained in excess in municipal wastewater, becomes a nutrient medium for the development of many microorganisms, including pathogenic ones. Normal soil contains a large number of microorganisms that can cause severe infectious diseases. Usually, drinking water is protected from the invasion of these microorganisms by the fact that the content of available food for bacteria (easily oxidizable organic substances) in it is low and almost all of them are used by normal aquatic microflora. However, with a significant increase in the concentration of organic matter in the water, soil pathogens find enough food sources for themselves and can become a source of an outbreak. In addition, an increase in the amount of organic matter in water stimulates the growth of non-pathogenic microflora, which, in turn, serves as food for larger pathogens - a number of amoebae (as was the case, for example, with amoebae that caused

In addition to the immediate danger of the development of pathogenic organisms in water contaminated with domestic sewage, there is another indirect, unpleasant for humans, consequence of this type of pollution. During the decomposition of organic matter (both chemical and microbiological), as we mentioned above, oxygen is consumed. In the case of severe pollution, the content of oxygen dissolved in water drops so much that it is accompanied not only by fish kills, but also by the impossibility of the normal functioning of microbiological communities. The aquatic ecosystem is degrading. In flowing waters and in reservoirs, the picture of the consequences of pollution by domestic sewage looks different.

AT flowing waters, four zones follow each other downstream. They clearly show gradients in oxygen content (increase from downstream discharge point), nutrients and BOD. 5 (corresponding reduction), species composition biological communities.

The first zone is the zone complete degradation where the mixing of waste and river waters. Next is the zone of active decomposition, in which microorganisms destroy most ingested organic matter. This is followed by water quality recovery zones and finally clean water.

Even at the beginning of the twentieth century. R. Kolkwitz and M. Marsson gave lists of indicator organisms for each of these zones, creating the so-called saprobity scale (from “sapros”, gr. - rotten).

AT the first zone - polysaprobic contains a significant amount of unstable organic substances and products of their anaerobic decay, a lot of protein substances. There is no photosynthesis, and oxygen enters the water only from the atmosphere, being completely spent on oxidation. Anaerobic bacteria produce methane Desulfovibrio

82 desulfuricans reduces sulfates to hydrogen sulfide, which contributes to the formation of black iron sulfide. Due to this, the sludge is black, with the smell of hydrogen sulfide. There are a lot of saprophytic microflora, filamentous bacteria, sulfur bacteria, protozoa - ciliates, colorless flagellates, oligochaetes - tubificid.

AT following her b-mesosaprobic zone is aerobic decay of organic matter. Ammonium bacteria metabolize nitrogen compounds with the formation of ammonia. The high content of carbon dioxide, oxygen is still low, but there is no more hydrogen sulfide and methane, BOD5 is tens of mg l-1. Saprophytic bacteria number in tens and hundreds of thousands in 1 ml. Iron is present in oxide and ferrous forms. Oxidation-reduction processes take place. Silt grey. Organisms that have adapted to a lack of oxygen and a high content of carbon dioxide predominate. Many plant organisms with mixotrophic nutrition. Filamentous bacteria, fungi, oscillators, chlamydomonas, euglenas develop in the mass. There are sessile ciliates, rotifers, many flagellates. Many tubificids and chironomid larvae.

In the β-mesosaprobic zone, there are practically no unstable organic substances; they are almost completely mineralized. Saprophytes - thousands of cells per ml. The content of oxygen and carbon dioxide varies depending on the time of day. The silt is yellow, there are oxidative processes, a lot of detritus. There are many organisms with autotrophic nutrition, water blooming is observed. There are diatoms, green, a lot of protococcal algae. A hornwort appears. There are many rhizopods, sunflowers, ciliates, worms, molluscs, chironomid larvae. There are crustaceans and fish.

The oligosaprobic zone corresponds to the pure water zone. Flowering does not happen, the content of oxygen and carbon dioxide is constant. There is little detritus, autotrophic organisms and worms, mollusks, and chironomids at the bottom. There are many larvae of mayflies, stoneflies, you can meet sterlet, minnow, trout.

AT reservoirs of slow water exchange, the picture depends on the size of the reservoir and the mode of wastewater discharge. In large reservoirs (seas, large lakes) around a permanent source, concentrically located, poly-, meso and oligosaprobic zones. This pattern may persist indefinitely. for a long time, if the self-cleaning potential of the reservoir allows it to cope with the incoming load. If the reservoir is small, then it is transformed, as

"Pollution of water bodies with domestic wastewater"

Introduction…………………………………………………………….

Main types of pollution of the hydrosphere……………………. Pollution by domestic sewage……………………..

3.1 Consequences of pollution from domestic wastewater ….

Effect of pollution on water bodies………………………………………………………………………………………………………………………………………………………………………………………………… ……..

Conclusion………………………………………………………

Application……………………………………………………..

INTRODUCTION

The most well-known source of water pollution, which has traditionally been the focus of attention, is domestic (or municipal) wastewater. Urban water consumption is usually estimated based on the average daily water consumption per person, which in the United States is approximately 750 liters and includes drinking water, for cooking and personal hygiene, for the operation of household plumbing devices, as well as for watering lawns and lawns, extinguishing fires, washing streets and other urban needs. Almost all used water goes to the sewer. Since a huge volume of feces enters wastewater every day, the main task of municipal services in the processing of domestic wastewater in sewage treatment plants is to remove pathogens. At reuse Inadequately treated fecal effluents, the bacteria and viruses they contain can cause intestinal diseases (typhoid, cholera and dysentery), as well as hepatitis and poliomyelitis. Soap, synthetic washing powders, disinfectants, bleaches and other household chemicals are present in dissolved form in wastewater. Paper waste comes from residential buildings, including toilet paper and baby diapers, vegetable and animal waste. Rain and melt water flows from the streets into sewers, often with sand or salt used to accelerate the melting of snow and ice on the roadway and sidewalks.

1. The main types of pollution of the hydrosphere

Pollution of water resources is understood as any changes in the physical, chemical and biological properties of water in reservoirs due to the discharge of liquid, solid and gaseous substances into them, which 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 objects from which the discharge or other entry into water bodies of harmful substances that degrade the quality of surface waters, limit their use, and also negatively affect the state of the bottom and coastal water bodies.

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

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

chemical - the presence in the water of organic and inorganic substances of toxic and non-toxic action;

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

("1") radioactive - the presence of radioactive substances in surface or ground 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 municipal enterprises, large livestock complexes, production waste from the development of ore minerals; water mines, mines, processing and alloying of timber; water and rail transport discharges; flax primary processing waste, pesticides, etc. Pollutants entering natural water bodies lead to qualitative changes in water, which are mainly manifested in a change in the physical properties of water, in particular, the appearance of unpleasant odors, tastes, etc.); in changing 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.

Wastewater is divided into three groups: fan, or fecal; household, including drains from the galley, showers, laundries, etc.; subsoil, or oil-containing.

For fan waste water characterized by high bacterial pollution, as well as organic pollution (chemical oxygen demand reaches mg / l.). the volume of these waters is relatively small.

Household waste water characterized by low organic pollution. This wastewater is usually discharged overboard as it is generated. Dumping them is prohibited only in the zone of sanitary protection.

Podslanye waters formed in the engine rooms of ships. They are distinguished by a high content of petroleum products.

Industrial wastewater is polluted mainly by industrial waste and emissions. Their quantitative and qualitative composition is diverse and depends on the industry, its technological processes; they are divided into two main groups: containing inorganic impurities, including toxic, and containing poisons.

The first group includes wastewater from soda, sulfate, nitrogen-fertilizer plants, processing plants for lead, zinc, nickel ores, etc., which contain acids, alkalis, heavy metal ions, etc. Wastewater from this group mainly changes the physical water properties.

Wastewater of the second group is discharged by oil refineries, petrochemical plants, organic synthesis enterprises, coke-chemical plants, etc. The wastewater contains various petroleum products, ammonia, aldehydes, resins, phenols and other harmful substances. The harmful effect of wastewater of this group lies mainly in oxidative processes, as a result of which the oxygen content in water decreases, the biochemical demand for it increases, and the organoleptic indicators of water deteriorate.

Pollution from sewage from industrial production, as well as domestic sewage, leads to eutrophication reservoirs - their enrichment with nutrients, leading to excessive development of algae, and to the death of other aquatic ecosystems with stagnant water (lakes, ponds), and sometimes to waterlogging of the area.

Phenol is a rather harmful pollutant of industrial waters. It is found in the wastewater of many petrochemical plants. At the same time, the biological processes of reservoirs, the process of their self-purification, are sharply reduced, the water acquires a specific smell of carbolic acid.

The life of the population of reservoirs is adversely affected by wastewater from the pulp and paper industry. Oxidation of wood pulp is accompanied by the absorption of a significant amount of oxygen, which leads to the death of eggs, fry and adult fish. Fibers and other insoluble matter clog the water and make it worse physiochemical properties. Mole alloys adversely affect fish and their food - invertebrates. From rotting wood and bark, various tannins are released into the water. Resin and other extractive products decompose and absorb a lot of oxygen, causing the death of fish, especially juveniles and eggs. In addition, mole alloys heavily clog rivers, and driftwood often completely clogs their bottom, depriving fish of spawning grounds and food places.

Oil and oil products present stage are the main pollutants of inland waters, waters and seas, the World Ocean. Getting into water bodies, they create various forms of pollution: an oil film floating on the water, oil products dissolved or emulsified in water, heavy fractions settled to the bottom, etc. This complicates the processes of photosynthesis in water due to the termination of access sun rays and also causes death of plants and animals. This changes the smell, taste, color, surface tension, viscosity of water, the amount of oxygen decreases, harmful organic substances appear, water acquires toxic properties and poses a threat not only to humans. 12 g of oil makes a ton of water unfit for consumption. Each ton of oil creates an oil film on an area of ​​up to 12 square meters. km. Restoration of affected ecosystems takes 10-15 years.

Nuclear power plants pollute rivers with radioactive waste. Radioactive substances are concentrated by the smallest planktonic microorganisms and fish, then they are transferred along the food chain to other animals. It has been established that the radioactivity of planktonic inhabitants is thousands of times higher than the water in which they live.

Wastewater with increased radioactivity (100 curies per 1 liter or more) is subject to disposal in underground drainless pools and special tanks.

Population growth, the expansion of old and the emergence of new cities have significantly increased the flow of domestic wastewater into inland waters. These effluents have become a source of pollution of rivers and lakes with pathogenic bacteria and helminths. Synthetic detergents widely used in everyday life pollute water bodies to an even greater extent. They are also widely used in industry and agriculture. The chemicals contained in them, entering rivers and lakes with sewage, have a significant impact on the biological and physical regime of water bodies. As a result, the ability of water to saturate with oxygen decreases, and the activity of bacteria that mineralize organic substances is paralyzed.

The pollution of water bodies with pesticides and mineral fertilizers, which come from the fields along with jets of rain and melt water, causes serious concern. As a result of research, for example, it has been proven that insecticides contained in water in the form of suspensions dissolve in oil products that pollute rivers and lakes. This interaction leads to a significant weakening of oxidative functions. aquatic plants. Getting into water bodies, pesticides accumulate in plankton, benthos, fish, and through the food chain they enter the human body, affecting both individual organs and the body as a whole.

2. Household (hozfekalnye) sewage.

Domestic wastewater accounts for 20% of the total volume of wastewater entering surface water bodies. If the volumes of industrial effluents and the amount of pollutants in them can be reduced through the introduction of circulating water supply systems, changes in the technology of wastewater treatment, then household wastewater is characterized by a constant increase in their volumes due to population growth, an increase in municipal water consumption, improvement sanitary and hygienic living conditions in modern cities and towns. The amount of pollutants in domestic wastewater is relatively stable - in the volume of pollution per inhabitant, which makes it possible to calculate the volume of discharged pollution depending on the number of inhabitants, the volume of water consumption, socio-economic lifestyle, etc. one resident are shown in Table No. 1.

Number of pollutants per person

Table 1

("3") 3. Pollution by domestic sewage.

The oldest type of water pollution is direct human waste. In terms of dry matter, each adult "produces" about 20 kg of organic matter, 5 kg of nitrogen and 1 kg of phosphorus per year. Initially, these wastes were directly used as fertilizers, then

the first earthen latrines appeared. Part of the waste inevitably ended up in sources of drinking water. That is why large cities already in antiquity began to build water pipes from sources quite remote from crowded places. With the advent of water closets, the idea of ​​a simple

solving the problem - breeding waste and removing it from the place of discharge. The volumes, and then the composition of wastewater to be treated, have changed significantly. At present, domestic sewage comes not only from residential buildings, but also from hospitals, canteens, laundries, small industrial enterprises, etc. Modern domestic sewage, in addition to easily oxidizable organic substances and biogenic elements, contains many substances, used in everyday life: detergents and surfactants, chemicals, drugs, etc. Easily oxidizable organic substances entering watercourses and reservoirs undergo chemical and microbiological oxidation there. To measure the content of organic substances in water, it is customary to use the value of biochemical oxygen consumption for 5 days. (BOD5, BOD5 – Biochemical Oxygen Demand). It is determined by the difference in the oxygen content in water during sampling and after five days of incubation without oxygen. BOD5, reflecting the content of easily oxidizable

organics in water is a universal indicator that can be used to compare the degree of pollution from different sources.

3.1 Consequences of pollution by domestic wastewater.

Easily oxidizable organic matter, contained in excess in municipal wastewater, becomes a nutrient medium for the development of many microorganisms, including pathogenic ones. Normal soil contains a large number of microorganisms that can cause severe infectious diseases. Normally, drinking water is protected from the intrusion of these

microorganisms in that the content of available food for bacteria (easily oxidizable organic substances) in it is small and almost all of them are used by normal aquatic microflora. However, with a significant increase in the concentration of organic matter in the water, soil pathogens find enough food sources for themselves and can become a source of an outbreak.

In addition to the direct danger of the development of pathogenic organisms in water contaminated with domestic wastewater, there is another indirect, unpleasant consequence for humans of this type of pollution. During the decomposition of organic matter (both chemical and microbiological), as we mentioned above,

oxygen is consumed. In the case of severe pollution, the content of oxygen dissolved in water drops so much that it is accompanied not only by fish kills, but also by the impossibility of the normal functioning of microbiological communities.

The aquatic ecosystem is degrading. In flowing waters and reservoirs, the picture of the consequences of pollution by domestic sewage looks different.

In flowing waters, four zones follow each other downstream. They clearly show the gradients of oxygen content (increase from the point of discharge downstream), nutrients and BOD5 (corresponding decrease), species composition of biological communities.

The first zone is the zone of complete degradation, where the mixing of sewage and river waters takes place. Further, there is a zone of active decomposition, in which microorganisms destroy most of the organic substances that have fallen. This is followed by water quality recovery zones and finally clean water.

Even at the beginning of the twentieth century. R. Kolkwitz and M. Marsson gave lists of indicator organisms for each of these zones, creating the so-called saprobity scale (from the Greek sapros - rotten). The first zone, polysaprobic, contains a significant amount of

number of unstable organic substances and products of their anaerobic decay, a lot of protein substances. There is no photosynthesis, and oxygen enters the water only from the atmosphere, being completely spent on oxidation. Anaerobic bacteria produce methane, Desulfovibrio desulphuricans reduces sulfates to hydrogen sulfide, which contributes to the formation of black iron sulfide. Due to this, the sludge is black, with the smell of hydrogen sulfide. There are a lot of saprophytic microflora, filamentous bacteria, sulfuric bacteria, protozoa - ciliates, colorless flagellates, oligochaetes-tubificids.

In the α-mesosaprobic zone following it, aerobic decomposition of organic substances takes place. Ammonium bacteria metabolize nitrogen compounds with the formation of ammonia. The high content of carbon dioxide, oxygen is still low, but hydrogen sulfide and methane are no longer there, BOD5 is tens of milligrams per

liter. Saprophytic bacteria number in tens and hundreds of thousands in 1 ml. Iron is present in oxide and ferrous forms.

Oxidation-reduction processes take place. Silt grey. Organisms that have adapted to a lack of oxygen and a high content of carbon dioxide predominate. Many plant organisms with mixotrophic nutrition. Filamentous bacteria, fungi, oscillators, chlamydomonas, euglenas develop in the mass. There are sessile ciliates, rotifers, many

("4") flagella. Many tubificids and chironomid larvae.

In the β-mesosaprobic zone, there are practically no unstable organic substances; they are almost completely mineralized. Saprophytes - thousands of cells in 1 ml. The content of oxygen and carbon dioxide varies depending on the time of day. The silt is yellow, there are oxidative processes, a lot of detritus. Many organisms

with autotrophic nutrition, water blooming is observed. There are diatoms, green, a lot of protococcal algae. A hornwort appears. There are many rhizopods, sunflowers, ciliates, worms, molluscs, chironomid larvae. There are crustaceans and fish.

The oligosaprobic zone corresponds to the pure water zone. Flowering does not happen, the content of oxygen and carbon dioxide is constant.

There is little detritus, autotrophic organisms and worms, mollusks, and chironomids at the bottom. There are many larvae of mayflies, stoneflies, you can meet sterlet, minnow, trout.

In reservoirs of slow water exchange, the picture depends on the size of the reservoir and the mode of wastewater discharge. In large reservoirs (seas, large lakes), concentrically located polymeso and oligosaprobic zones are formed around a permanent source. Such a picture can persist indefinitely if the self-cleaning potential of the reservoir allows it to cope with the incoming load. If the water body is small, then it transforms, as pollution enters from the oligosaprobic to the polysaprobic state, and when the load is removed, it can return to the oligosaprobic state.

4. Impact of pollution on water bodies

Pure water is transparent, colorless, odorless and tasteless, inhabited by many fish, plants and animals. Polluted waters are cloudy, foul-smelling, unsuitable for drinking, and often contain large amounts of bacteria and algae. The water self-purification system (aeration with running water and sedimentation of suspended particles on the bottom) does not work due to an excess of anthropogenic pollutants in it.

Decreased oxygen content. The organic matter contained in the wastewater is decomposed by the enzymes of aerobic bacteria, which absorb the oxygen dissolved in the water and release carbon dioxide as the organic residues are assimilated. Common end products of decomposition are carbon dioxide and water, but many other compounds can be formed. For example, bacteria convert waste nitrogen into ammonia (NH3), which combines with sodium, potassium, or other chemical elements, forms salts of nitric acid - nitrates. Sulfur is converted into hydrogen sulfide compounds (substances containing the radical - SH or hydrogen sulfide H2S), which gradually turn into sulfur (S) or sulfate ion (SO4-), which also forms salts.

In waters containing faecal matter, plant or animal residues coming from food industry enterprises, paper fibers and cellulose residues from pulp and paper industry enterprises, the decomposition processes proceed in almost the same way. Since aerobic bacteria use oxygen, the first result of the decomposition of organic residues is a decrease in the oxygen content dissolved in the receiving waters. It varies with temperature, and to some extent with salinity and pressure. Fresh water at 20°C and intensive aeration, one liter contains 9.2 mg of dissolved oxygen. As the water temperature rises, this indicator decreases, and when it cools, it increases. According to the regulations in force for the design of municipal wastewater treatment plants, the decomposition of organic substances contained in one liter of municipal wastewater of normal composition at a temperature of 20 ° C requires approximately 200 mg of oxygen for 5 days. This value, called Biochemical Oxygen Demand (BOD), is taken as the standard for calculating the amount of oxygen needed to treat a given amount of wastewater. The value of BOD of wastewater from enterprises of the leather, meat processing and sugar refinery industries is much higher than that of municipal wastewater.

In shallow streams with fast current, where water is intensively mixed, oxygen coming from the atmosphere compensates for the depletion of its reserves dissolved in water. At the same time, carbon dioxide, which is formed during the decomposition of substances contained in wastewater, escapes into the atmosphere. Thus, the period of adverse effects of organic decomposition processes is reduced. Conversely, in low-flowing water bodies, where the waters mix slowly and are isolated from the atmosphere, the inevitable decrease in oxygen content and an increase in carbon dioxide concentration entail serious changes. When the oxygen content decreases to a certain level, fish die and other living organisms begin to die, which, in turn, leads to an increase in the volume of decaying organic matter.

Most of the fish die due to poisoning by industrial and agricultural effluents, but many also die from a lack of oxygen in the water. Fish, like all living things, take in oxygen and release carbon dioxide. If there is little oxygen in the water, but a high concentration of carbon dioxide, the intensity of their respiration decreases (it is known that water with a high content of carbonic acid, i.e. carbon dioxide dissolved in it, becomes acidic). In waters experiencing thermal pollution, conditions are often created that lead to the death of fish. There, the oxygen content decreases, since it is slightly soluble in warm water, but the demand for oxygen increases sharply, since the rate of its consumption by aerobic bacteria and fish increases. The addition of acids, such as sulfuric acid, to drainage water from coal mines also greatly reduces the ability of some fish to extract oxygen from the water.

5. Purification of household sewage.

Sewerage is a complex of engineering structures and sanitary measures that ensure the collection and removal of polluted wastewater from populated areas and industrial enterprises, their purification, neutralization and disinfection. Cities and other settlements discharge 22 billion m3 of sewage per year through sewerage systems. Of these, 76% passes through treatment facilities, including 94% - facilities for complete biological treatment. Through municipal sewerage systems, 13.3 billion m3 of wastewater is annually discharged into surface water bodies, of which 8% of wastewater is treated at treatment facilities to the established standards, and the remaining 92% is discharged contaminated. Of these, 82% are discharged insufficiently purified and 18% without any purification. Most of the wastewater treatment plants are overloaded, and almost half require reconstruction.

Domestic wastewater treatment can be carried out mechanically and biological methods. During mechanical treatment, wastewater is divided into liquid and solid substances: the liquid part is subjected to biological treatment, which can be natural or artificial. Natural biological treatment is carried out in the fields of filtration and irrigation, in biological ponds, and artificial - on special equipment (biofilters, aeration tanks). Sludge is processed on sludge sites or in digesters.

With a general sewerage system, all types of wastewater from urban areas, including surface runoff, are discharged through one pipeline network. The disadvantage of such a system is periodic discharges into water bodies through storm drains of some part of industrial and domestic wastewater. Currently, the most widely used in our country is the sewerage system, which provides for the installation of pipeline networks: through the industrial network, household and industrial wastewater is supplied to treatment facilities, and through the drain, as a rule, without treatment, it is discharged to the nearest water body rain and melt water, as well as water generated during irrigation and washing of road surfaces. The most promising from the point of view of protecting water bodies from pollution by surface runoff from cities is a semi-separated sewerage system. With its help, all industrial and domestic waters of the city and most of the surface runoff generated on its territory are diverted for treatment. In the joint treatment of industrial and domestic wastewater, the content of suspended and floating substances, products that can destroy or clog communications, explosive and combustible substances, as well as temperature are regulated.

Some chemicals affect microorganisms, disrupting their vital functions. Thus, phenol, formaldehyde, ethers and ketones cause denaturation of protoplasmic proteins or destroy cell membranes. Particularly toxic salts of heavy metals, which in descending toxicity can be arranged in a row: mercury, antimony, lead, cesium, cadmium, cobalt, nickel, copper, iron.

For disinfection of wastewater, the dose of chlorine is selected so that the content of Escherichia coli in the water discharged into the reservoir does not exceed 1000 in 1 liter, and the level of residual chlorine is at least 1.5 mg/l with a 30-minute contact or 1 mg/l with 60 minutes of contact. Disinfection is carried out with liquid chlorine, bleach or sodium hypochlorite, obtained on site in electrolyzers. Chlorine management of sewage treatment facilities should allow increasing the estimated dose of chlorine by 1.5 times.

6. Discharge of wastewater into water bodies

The amount of wastewater released into wastewater facilities is determined using the maximum allowable discharge (MPD). MPD is understood as the mass of a substance in wastewater, the maximum allowable for discharge with the established regime at a given point of a water body per unit of time in order to ensure water quality standards at the control point. MPD is calculated based on the highest average hourly wastewater flow rate q (in m3/h) of the actual period of wastewater discharge.

("5") Reservoirs are polluted mainly as a result of the discharge of sewage into them from industrial enterprises and settlements. As a result of wastewater discharge, the physical properties of water change (temperature rises, transparency decreases, color, tastes, odors appear); floating substances appear on the surface of the reservoir, and sediment forms at the bottom; changes chemical composition water (the content of organic and inorganic substances increases, toxic substances appear, the oxygen content decreases, the active reaction of the environment changes, etc.); the qualitative and quantitative bacterial composition changes, pathogenic bacteria appear. Polluted reservoirs become unsuitable for drinking, and often for technical water supply; lose their fishery importance, etc.

The general conditions for the release of wastewater of any category into surface water bodies are determined by their national economic significance and the nature of water use. After the release of wastewater, some deterioration in the quality of water in reservoirs is allowed, but this should not noticeably affect his life and the possibility of further use of the reservoir as a source of water supply, for cultural and sports events, fishery purposes.

Supervision over the fulfillment of the conditions for the discharge of industrial wastewater into water bodies is carried out by sanitary and epidemiological stations and basin departments.

The water quality standards for reservoirs for domestic and domestic water use establish the quality of water for reservoirs for two types of water use: the first type includes sections of reservoirs used as a source for centralized or non-centralized domestic and drinking water supply, as well as for water supply of food industry enterprises; to the second type - sections of reservoirs used for swimming, sports and recreation of the population, as well as those located within the boundaries of settlements.

The assignment of water bodies to one or another type of water use is carried out by the bodies of the State Sanitary Supervision, taking into account the prospects for the use of water bodies.

The water quality standards for reservoirs given in the rules apply to sites located on flowing reservoirs 1 km upstream of the nearest water use point, and on stagnant reservoirs and reservoirs 1 km on both sides of the water use point.

Much attention is paid to the prevention and elimination of pollution of the coastal areas of the seas. Sea water quality standards, which must be ensured when discharging wastewater, refer to the water use area within the allotted boundaries and to sites at a distance of 300 m away from these boundaries. When using coastal areas of the seas as a receiver of industrial wastewater, the content of harmful substances in the sea should not exceed the MPC established for sanitary-toxicological, general sanitary and organoleptic limiting indicators of harmfulness. At the same time, the requirements for the discharge of wastewater are differentiated in relation to the nature of water use. The sea is considered not as a source of water supply, but as a medical, health-improving, cultural and household factor.

Pollutants entering rivers, lakes, reservoirs and seas make significant changes to the established regime and disrupt the equilibrium state of water ecological systems. As a result of the processes of transformation of substances polluting water bodies, occurring under the influence of natural factors, in water sources there is a complete or partial restoration of their original properties. In this case, secondary decomposition products of pollution can be formed that have a negative impact on water quality.

Self-purification of water in reservoirs is a set of interrelated hydrodynamic, physicochemical, microbiological and hydrobiological processes leading to the restoration of the original state of a water body. Due to the fact that wastewater from industrial enterprises may contain specific contaminants, their discharge into the city drainage network is limited by a number of requirements. Industrial wastewater released into the drainage network should not: disrupt the operation of networks and structures; have a destructive effect on the material of pipes and elements of treatment facilities; contain more than 500 mg/l of suspended and floating substances; contain substances that can clog networks or deposit on pipe walls; contain combustible impurities and dissolved gaseous substances capable of forming explosive mixtures; contain harmful substances that prevent biological wastewater treatment or discharge into a reservoir; have a temperature above 40 C. Industrial wastewater that does not meet these requirements must be pre-treated and only then discharged into the city drainage network.

Conclusion.

Domestic drains

Today, domestic wastewater is a big environmental and economic problem. Organic materials enter the hydrosphere from them. They decompose under the action of bacteria with the consumption of oxygen. With sufficient access to oxygen, aerobic bacteria easily and quickly turn sewage into an environmentally friendly material. With insufficient oxygen access to wastewater, aerobic bacteria slow down their activity, as a result of which anaerobic bacteria begin to develop and the process of decay begins.

Domestic wastewater that has not been biologically treated or not well treated may contain disease-causing bacteria and viruses that, if released into drinking water, can cause dangerous diseases. Vegetables fertilized with sewage treatment sludge can also be contaminated. Typhoid outbreaks are often caused by oysters and other aquatic invertebrates whose habitats are contaminated with untreated sewage.

Agricultural wastewater contains phosphorus, nitrogen and is often a source of nutrients for plankton and algae. With an increased content of these elements in the water, there is a rapid development of vegetation that absorbs oxygen. This, in turn, negatively affects the activity of microorganisms that process organic substances.

With sewage, phenols, pesticides, detergents also enter the water, the process of decomposition of which occurs slowly, or does not decompose at all. Then, along the food chains from the organisms of fish and other aquatic animals, they enter human body, and negatively affect human health, which can subsequently cause various infectious and chronic diseases.

On the this moment developments are known that will not allow reaching an ecological impasse - these are technologies waste-free production and biological processing of wastewater into environmentally friendly, useful resources. Biological treatment is one of the most promising areas, and all the best of biological treatment is contained in the autonomous sewage system Topas.

APPENDIX

Article 250 of the Criminal Code of the Russian Federation Water pollution

1. Pollution, clogging, depletion of surface or ground water, sources of drinking water supply or other change in their natural properties, if these acts have caused significant harm to an animal or flora, fish stocks, forestry or agriculture, are punishable by a fine in the amount of 100 to 200 minimum dimensions wages or in the amount of wages or other income of the convicted person for a period of one to two months, or by deprivation of the right to hold certain positions or engage in certain activities for up to five years, or by corrective labor for up to one year, or by arrest for up to three years. months.

2. The same acts that caused harm to human health or mass death animals, as well as those committed on the territory of a nature reserve or sanctuary, or in a zone of ecological disaster or in a zone of ecological emergency, - months, or correctional labor for a term of one to two years, or imprisonment for a term of up to three years.

("6") 3. Acts provided for by paragraphs 1 or 2 of this Article, which negligently caused the death of a person, are punishable by deprivation of liberty for a term of two to five years.

1. The object of the crime under consideration is public relations in the field of water protection and environmental safety. The subject of the crime is surface water, including surface watercourses and reservoirs on them, surface water bodies, glaciers and snowflakes, groundwater (aquifer, basins, deposits and natural outlet of groundwater).

Internal sea ​​waters, territorial sea of ​​the Russian Federation, open waters The oceans do not belong to the subject of this crime.

2. The objective side of the crime is pollution, clogging, depletion or other change in the natural properties of the above components of the hydrosphere with untreated and non-neutralized sewage, waste and garbage or toxic or aggressive in relation to the quality of the environment with industrial products (oil, oil products, chemicals) , agricultural, municipal and other enterprises and organizations.

In accordance with Art. 1 of the Water Code of the Russian Federation, adopted by the State Duma on October 18, 1995, clogging of water bodies - discharge or otherwise entering water bodies, as well as the formation of harmful substances in them that worsen the quality of surface and ground waters, limit the use or adversely affect the condition the bottom and shores of such objects.

Clogging of water bodies is the discharge or otherwise entry into water bodies of objects or suspended particles that worsen the condition and impede the use of such objects.

Water depletion is a steady reduction in reserves and deterioration in the quality of surface and groundwater.

The quality of the environment and its main objects, including water, is determined by special regulations- extremely allowable concentrations harmful substances (MAC). Discharges of untreated sewage, industrial and agricultural waste into rivers, lakes, reservoirs, and other inland water bodies sharply increase the MPC in water sources and thereby significantly reduce their quality. Discharge - the entry of harmful substances in wastewater into a water body is determined by GOST.

Bibliography:

Furon R. The problem of water on the globe. L., 1966 Lvovich water from pollution. L., 1977, Shvetsov and water. M., 1979 Lvovich and life: Water resources, their transformation and protection. M., 1986