Industrial enterprises as sources of environmental pollution. Air pollution by major industries

The change in the gas composition of the atmosphere is the result of a combination of natural phenomena in nature and human activity. But which of these processes is currently dominant? In order to find out, we first clarify what pollutes the air. Its relatively constant composition has been subject to significant fluctuations in recent years. Let us consider the main problems of emission control and air purity protection using the example of this work in cities.

Does the composition of the atmosphere change?

Standing next to a smoldering garbage heap is like being on the most polluted street of a metropolis. The danger of carbon monoxide is that it binds the hemoglobin of the blood. The resulting carboxyhemoglobin can no longer deliver oxygen to cells. Other substances that pollute the air can cause disruption of the bronchi and lungs, poisoning, exacerbation of chronic diseases. For example, when carbon monoxide is inhaled, the heart works with increased stress, since not enough oxygen is supplied to the tissues. In this case, cardiovascular diseases may worsen. An even greater danger is posed by the combination of carbon monoxide with pollutants in industrial emissions and vehicle exhaust.

Pollutant Concentration Standards

Hazardous emissions come from metallurgical, coal, oil and gas processing plants, energy facilities, construction and utilities. Radioactive contamination from the explosions at the Chernobyl nuclear power plant and nuclear power plants in Japan has spread globally. There is an increase in the content of carbon oxides, sulfur, nitrogen, freons, radioactive and other dangerous emissions in different parts of our planet. Sometimes toxins are found far from the place where the factories that pollute the air are located. The situation that has arisen is an alarming and difficult to solve global problem of mankind.

Back in 1973, the relevant committee of the World Health Organization (WHO) proposed criteria for assessing the quality of atmospheric air in cities. Experts have found that the state of human health depends on environmental conditions by 15-20%. On the basis of many studies in the XX century, the permissible levels of the main pollutants that are harmless to the population were determined. For example, the average annual concentration of suspended particles in the air should be 40 μg / m 3. The content of sulfur oxides should not exceed 60 μg / m 3 per year. For carbon monoxide, the corresponding average is 10 mg / m 3 for 8 hours.

What is the Maximum Allowable Concentration (MPC)?

By the decree of the Chief State Sanitary Doctor of the Russian Federation, the hygienic standard for the content of almost 600 harmful compounds in the atmosphere of settlements was approved. pollutants in the air, compliance with which indicates the absence of adverse effects on people and sanitary conditions. The standard specifies the hazard classes of compounds, the values of their content in the air (mg / m 3). These indicators are updated when new data on the toxicity of certain substances become available. But that's not all. The document contains a list of 38 substances for which a ban on emission has been introduced due to their high biological activity.

How is the state control in the field of atmospheric air protection carried out?

Anthropogenic changes in the composition of the air lead to negative consequences in the economy, deteriorate health and reduce the life expectancy of people. The problems of increasing the release of harmful compounds into the atmosphere are of concern to both governments, state and municipal authorities, and the public, ordinary people.

The legislation of many countries provides for the start of construction, reconstruction, modernization of almost all objects of the economy. The regulation of pollutants in the air is being carried out, measures are being taken to protect the atmosphere. The issues of reducing the anthropogenic load on the environment, reducing emissions and discharges of pollutants are being addressed. In Russia, federal laws on the protection of the environment, atmospheric air, and other legislative and regulatory legal acts governing activities in the environmental sphere have been adopted. State environmental control is carried out, pollutants are limited, and emissions are rationed.

What is MPE?

Air-polluting enterprises should conduct an inventory of the sources of exposure to harmful compounds in the air. Usually this work finds its logical continuation when determining the need to obtain this document is associated with the regulation of the technogenic load on the atmospheric air. Based on the information included in the MPE volume, the enterprise receives a permit for the emission of pollutants into the atmosphere. Data on regulatory emissions are used to calculate payments for negative environmental impacts.

If there is no MPE volume and no permit, then enterprises pay 2, 5, 10 times more for emissions from pollution sources located on the territory of an industrial facility or other industry. The regulation of pollutants in the air leads to a reduction in the negative impact on the atmosphere. There is an economic incentive to carry out measures to protect nature from the ingress of alien compounds into it.

Payments for environmental pollution from enterprises are accumulated by local and federal authorities in specially created budgetary environmental funds. Financial resources are spent on environmental protection activities.

How is the air purified and protected at industrial and other facilities?

Polluted air is purified by different methods. Filters are installed on the pipes of boiler houses and processing enterprises, there are dust and gas collecting installations. Through the use of thermal decomposition and oxidation, some toxic substances are converted into harmless compounds. The capture of harmful gases in emissions is carried out by condensation methods, sorbents are used to absorb impurities, catalysts for cleaning.

Prospects for activities in the field of air protection relate to work to reduce the release of pollutants into the atmosphere. It is necessary to develop laboratory monitoring of harmful emissions in cities and on busy transport routes. Work should continue on the introduction of systems for the capture of solid particles from gaseous mixtures at enterprises. We need cheap modern devices for cleaning emissions from toxic aerosols and gases. In the field of state control, an increase in the number of posts is required to check and regulate the toxicity of vehicle exhaust gases. Energy industry enterprises and vehicles should be converted to less harmful, from the point of view of ecology, types of fuel (for example, natural gas, biofuel). When they burn, they release less solid and liquid pollutants.

What role do green spaces play in air purification?

It is difficult to overestimate the contribution of plants to the replenishment of oxygen reserves on the Earth, trapping pollution. Forests are called "green gold", "lungs of the planet" for the ability of leaves to photosynthesize. This process consists in the absorption of carbon dioxide and water, the formation of oxygen and starch in the light. Plants release phytoncides into the air - substances that have a detrimental effect on pathogenic microbes.

Increasing the area of green spaces in cities is one of the most important environmental protection measures. Trees, shrubs, grasses and flowers are planted in the courtyards of houses, in parks, squares and along roads. Greening areas of schools and hospitals, industrial enterprises.

Scientists have found that plants such as poplar, linden, and sunflower absorb dust and harmful gaseous substances from industrial emissions and transport emissions best. Most of the phytoncides are emitted by coniferous plantations. The air in pine, fir, juniper forests is very clean and healthy.

1) Industrial pollution of the environment.

At all stages of his development, man was closely connected with the world around him. But since the emergence of a highly industrial society, dangerous human intervention in nature has increased dramatically, the volume of this intervention has expanded, it has become more diverse and now threatens to become a global threat to humanity. The consumption of non-renewable raw materials is increasing, more and more arable land is leaving the economy, so cities and factories are built on them. Man has to interfere more and more in the economy of the biosphere - that part of our planet in which life exists. The biosphere of the Earth is currently undergoing increasing anthropogenic impact. At the same time, several of the most significant processes can be identified, any of which does not improve the ecological situation on the planet.

The most large-scale and significant is the chemical pollution of the natural environment, pollutants of industrial origin. Over the past hundred years, the development of industry has "endowed" us with such production processes, the consequences of which at first a person could not yet imagine.

AIR POLLUTION.

Basically, there are three main sources of air pollution: industry, household boilers, transport. It is now generally accepted that industrial production pollutes the air the most. The main sources of air pollution are: thermal power plants and heating plants (burning fossil fuels), metallurgical enterprises, mechanical engineering, chemical production, mining and processing of mineral raw materials, open sources (mining, agricultural arable land, construction). Atmospheric pollutants are divided into primary, entering directly into the atmosphere, and secondary, resulting from the transformation of the latter. So, sulfur dioxide entering the atmosphere is oxidized to sulfuric anhydride, which interacts with water vapor and forms droplets of sulfuric acid. Specific pollutants entering the atmosphere are shown in Table 1.

The main sources of air pollution. Table 1.

Group	Aerosols	Gaseous emissions
Boilers and industrial furnaces	Ash, soot	NO 2, SO 2, as well as aldehydes (НСНО), organic acids, benzo (a) pyrene
Oil refining industry	Dust, soot	SO 2, H 2 S, NH 3, NOx, CO, hydrocarbons, mercaptans, acids, aldehydes, ketones, carcinogenic substances
Chemical industry	Dust, soot	Depending on the process (H 2 S, CS 2, CO, NH 3, acids, organic matter, solvents, volatile substances, sulfides, etc.)
Metallurgy and coke chemistry	Dust, oxides	SO 2, CO, NH 3, NOx, fluoride cyanide compounds compounds, organic substances, benzo (a) pyrene
Mining	Dust, soot	Process dependent (CO fluoride compounds, organic matter)
Food industry		NH 3, H 2 S (multicomponent mixtures of organic compounds)
Industry Building materials		CO, organic compounds

POLLUTION OF NATURAL WATER.

Industry is the main source of pollution of natural waters. Therefore, it turns out that when used, water is first polluted and then discharged into water bodies. Inland water bodies are polluted by sewage from various industries (metallurgy, oil refining, chemical, etc.).

Pollutants are divided into biological (organic microorganisms) that cause water fermentation; chemical, which change the chemical composition of water; physical, changing its transparency, temperature and other indicators. Biological pollution enters water bodies with industrial wastewater mainly from food, biomedical, and pulp and paper industries. Chemical pollutants enter water bodies with industrial effluents. These include: oil products, heavy metals and their compounds, mineral fertilizers, detergents. The most dangerous of them are: lead, mercury, cadmium. Physical pollution comes into a reservoir with sewage, during discharges from mine workings, open pits, during washings from the territories of industrial zones, cities, transport highways, due to the deposition of atmospheric dust.

As a result of anthropogenic activity, many water bodies of the world and our country are extremely polluted. The level of water pollution by some indicators exceeds the maximum permissible norms by tens of times. Anthropogenic impact on the hydrosphere leads to a decrease in drinking water supplies; changes in the state and development of flora and fauna of water bodies; violation of the circulation of many substances in the biosphere; a decrease in the biomass of the planet and, as a result, to the reproduction of oxygen. Not only primary pollution of surface waters is dangerous, but also secondary ones, which were formed as a result of a chemical reaction of substances in the aquatic environment.

POLLUTION OF THE WORLD OCEAN

Oil and petroleum products are the most common pollutants in the oceans. The greatest losses of oil are associated with its transportation from production areas. Emergency situations, overboard discharge of washing and ballast water by tankers - all this causes the presence of permanent fields of pollution along the routes of sea routes. Over the past 30 years, since 1964, about 2000 wells have been drilled in the World Ocean, of which 1000 and 350 industrial wells have been installed in the North Sea alone. Due to minor leaks, 0.1 million tons are lost annually. oil. Large masses of oil enter the seas along rivers, with domestic and storm water flows. With industrial effluents, 0.5 million tons are annually received. oil. Once in the marine environment, oil first spreads out in the form of a film, forming layers of varying thickness.

Pesticides The industrial production of pesticides is accompanied by the appearance of a large number of by-products that pollute wastewater. In the aquatic environment, representatives of insecticides, fungicides and herbicides are more common than others. The synthesized insecticides are divided into three main groups: organochlorine, organophosphorus and carbonates.

Synthetic surfactants. Detergents (surfactants) belong to a wide group of substances that lower the surface tension of water. They are part of synthetic detergents (CMC), widely used in everyday life and industry. Together with the wastewater of synthetic surfactants, they enter mainland waters and the marine environment. SMS contains sodium polyphosphates, in which detergents are dissolved, as well as a number of additional ingredients that are toxic to aquatic organisms.

Heavy metals. Heavy metals (mercury, lead, cadmium, zinc, copper, arsenic) are common and highly toxic pollutants. They are widely used in various industrial industries, therefore, despite treatment measures, the content of heavy metal compounds in industrial wastewater is quite high. Large masses of these compounds enter the ocean through the atmosphere. About half of the annual industrial production of mercury (910 thousand tons / year) enters the ocean in various ways. In areas polluted by industrial waters, the concentration of mercury in the solution and suspended matter increases dramatically. Contamination of seafood has repeatedly led to mercury poisoning of coastal populations. Lead is a typical trace element contained in all components of the environment: in rocks, soils, natural waters, the atmosphere, and living organisms. Finally, lead is actively dissipated into the environment in the course of human economic activity. These are emissions from industrial and domestic wastewaters, from the smoke and dust of industrial enterprises, from the exhaust gases of internal combustion engines. The migration flow of lead from the continent to the ocean goes not only with river flows, but also through the atmosphere. With continental dust, the ocean receives (20-30) tons of lead per year.

Discharge of waste into the sea for disposal (dumping). Many landlocked countries produce marine dumping of various materials and substances, in particular, dredged soil, drill slag, industrial waste, construction waste, solid waste, explosives and chemicals, and radioactive waste. The volume of burials was about 10% of the total mass of pollutants entering the World Ocean. The basis for dumping in the sea is the ability of the marine environment to process a large amount of organic and inorganic substances without much damage to the water. However, this ability is not unlimited.

Therefore, dumping is viewed as a necessary measure, a temporary tribute of society to imperfect technology. The slags of industrial production contain a variety of organic substances and compounds of heavy metals. During the discharge of the passage of the material through the water column, part of the pollutants passes into solution, changing the quality of the water, the other is sorbed by suspended particles and passes into bottom sediments. At the same time, the turbidity of the water increases. The presence of a large amount of organic matter creates a stable reducing environment in soils, in which a special type of sludge water appears, containing hydrogen sulfide, ammonia, metal ions

Thermal pollution. Thermal pollution of the surface of water bodies and coastal sea areas occurs as a result of the discharge of heated wastewater from power plants and some industrial industries. Discharge of heated water in many cases causes an increase in water temperature in reservoirs by 6-8 degrees Celsius. The area of hot water spots in coastal areas can reach 30 square kilometers. More stable temperature stratification prevents water exchange in the surface and bottom layers. The solubility of oxygen decreases, and its consumption increases, since with an increase in temperature, the activity of aerobic bacteria that decompose organic matter increases.

SOIL POLLUTION

Disturbance of the upper layers of the earth's crust occurs during: mining and enrichment; burial of household and industrial waste; conducting military exercises and tests.

Every year, a huge amount of rock mass is extracted from the bowels of the country, and about a third is involved in circulation, about 7% of the production volume is used in production. Most of the waste is not used and accumulates in dumps. Land pollution is significant as a result of sedimentation of toxic substances from the atmosphere. The most dangerous are enterprises of non-ferrous and ferrous metallurgy. The main pollutants include nickel, lead, benzpyrene, mercury, etc. Emissions from waste incineration plants containing tetraethyl lead, mercury, dioxins, etc. are dangerous. Emissions from thermal power plants contain benzpyrene, vanadium compounds, radionuclides, acids and other toxic substances. The zone of soil contamination near the pipes has a radius of 5 km or more. Arable land is intensively contaminated with fertilization and the use of pesticides. A particular danger is the use of industrial wastewater sludge as fertilizers, as a rule, saturated with wastes from galvanic and other industries.

The problem of environmental pollution is becoming more and more urgent. Every city has at least a few factories that emit harmful substances into the environment. Some enterprises install purification filters and the emission of harmful substances is significantly reduced. Moreover, the choice of funds directly depends on the type of activity of the enterprise: a metallurgical, chemical or construction plant. It will not be superfluous to study the legislation on hazardous waste passports.

Industrial enterprises emit nitrogen oxides, dust, smoke and other harmful substances into the air. Many factories release industrial waste into the reservoir and pollute rivers and seas. Significant sums of money are required to clean them. Chemical waste buried in the ground is especially dangerous. They are the ones that lead to global environmental pollution.

The most common filters are air filters. With their help, the air in the premises is already purified, because They filter the air in ventilation systems. However, it is much cheaper for many companies to pay fines for environmental pollution than to bleed off purification systems, because they are many times more expensive. Therefore, fines for pollution of the environment should be at least doubled, because cleaning it will require much more money.

Air pollution negatively affects not only human health, but also the planet itself. Irreparable harm is done to animals and plants around us.

Metallurgical plants and factories that produce aluminum, steel, produce chemicals and most pollute the environment. Many industrial plants emit small amounts of pollution, but fairly regularly.

Smog is one of the most common pollution from factories, which, in combination with various chemical processes and weather conditions, is extremely dangerous to human health. Smog negatively affects the respiratory and circulatory system of a person, weakens his immunity.

Due to environmental pollution, the number of heart diseases and cancers is increasing every year.

Plants that are engaged in the processing of the chemical, nuclear industry can emit very toxic and even radioactive substances into the atmosphere. The harmful substances that release this waste can cause the development of genetic diseases in humans and can be fatal.

Each state regulates at the legislative level the amount of emissions and their disposal. Many factories simply bury garbage in the ground in containers. This cannot be done due to the high risk of waste leakage.

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Title Federal State Budgetary Educational Institution

higher professional education

Ural State Mining University

Air pollution by industrial processes

Lecturer: Boltyrov V.B.

Student: Ivanov V.Yu.

group: ZChS-12

Yekaterinburg - 2014

Introduction

Conclusion

Introduction

Scientific and technological progress in the modern world has a great impact on the development of civilizations. At the same time, the impact of the growing share of industry on the environment is undeniable.

The biosphere of the Earth is currently undergoing increasing anthropogenic impact. Technological progress and related industries every year generate new types of waste that have a negative impact on the environment.

The most large-scale and significant is the chemical pollution of the environment by substances of a chemical nature that are not typical for it. Among them are gaseous and aerosol pollutants of industrial and domestic origin. The accumulation of carbon dioxide in the atmosphere is also progressing. Further development of this process will intensify the undesirable trend towards an increase in the average annual temperature on the planet.

As a result of human activity on an industrial scale, control over atmospheric pollution, as well as limiting hazardous emissions, is currently becoming an urgent problem. An important part of the industrialization process is the introduction of high-tech and safe production processes and, accordingly, the use of efficient systems for the disposal of industrial waste.

One of the areas of stabilization and subsequent improvement of the environment is the introduction of waste-free production, as well as the creation of an effective system of environmental certification of production and other facilities that are sources of environmental pollution.

Chapter 1. Classification of industrial pollution and waste

Environmental pollution is a complex of various influences of human society, leading to an increase in the level of harmful substances in the atmosphere, the emergence of new chemical compounds, particles and foreign objects, an excessive increase in temperature, noise, radioactivity, etc.

Sources of pollution of a modern enterprise, depending on the situation of occurrence, are divided into operational and emergency.

Operational pollution sources, in turn, include three large groups.

The first group unites sources of pollution resulting from imperfect technology. Thus, at an oil refinery, the first group of sources of air pollution is associated with the processes of catalytic cracking (burning off coke), the production of elemental sulfur (afterburning of residual hydrogen sulfide), the production of bitumen (afterburning gases from cubes of oxidizers), and the production of synthetic fatty acids (afterburning of saponification gases). The main sources of water pollution with technological waste are: electrical desalination of oil (water with a high content of salts and oil); processes of alkaline sulfuric acid refining of petroleum products - sulfur-alkaline effluents; steam distillation (effluents containing oil products); alkylation processes (acidic effluents); selective cleaning of oils, etc.

The second group of pollution sources is the equipment of the main technological shops and auxiliary production. The contaminating effect of the equipment does not depend on the process technology, but is the result of design flaws and the specifics of the equipment functioning. The second group of pollution sources includes: furnaces of technological units, barometric condensers, storage tanks for oil and oil products, oil traps, settling ponds, sludge collectors, pumps and compressors, flare equipment, loading racks, drying ovens of catalyst factories, catalyst circulation system in catalytic cracking. The group of equipment - sources of pollution - is the most numerous both in terms of the number of points-sources and the volume of emitted pollution.

The third group of sources of environmental pollution is the result of a low culture of equipment operation. Contamination of this group is manifested both in emergency situations and in normal operation conditions with low responsibility and qualifications of personnel or organizational shortcomings. The reasons for the appearance of this group of sources are, for example, leaks of oil and oil products during sampling, overflows when filling tanks, overflows when filling tanks on unloading racks, depressurization of equipment and valves due to its malfunction, release of oil products and reagents into the sewer in emergency situations, and when preparing equipment for repair.

Thus, harmful emissions are divided into three groups:

1) technological waste, sources of which are polluting processes;

2) loss of products as a result of imperfect equipment and low culture of its operation;

3) flue gases formed during the combustion of fuel in furnaces of technological installations, during the combustion of gases in a flare, etc.

The share of each group of pollutants in the total balance of harmful emissions varies at different enterprises.

Industrial pollution of the biosphere is divided into two main groups: material (i.e. substances), including mechanical, chemical and biological pollution, and energy (physical) pollution.

Mechanical contamination includes aerosols, solids and particles in water and soil.

Chemical pollution - a variety of gas, liquid and solid chemical compounds that interact with the biosphere.

Biological pollution - microorganisms and their metabolic products - is a qualitatively new type of pollution that has arisen as a result of the application of processes of microbiological synthesis of various types of microorganisms (yeast, actinomycetes, bacteria, molds, etc.).

Energy pollution includes all types of energy - thermal, mechanical (vibration, noise, ultrasound), light (visible, infrared and ultraviolet radiation), electromagnetic fields, ionizing radiation (alpha, beta, gamma, X-ray and neutron) - as waste from various industries. Some types of pollution, for example, radioactive waste and emissions generated by explosions of nuclear charges and accidents at nuclear power plants and enterprises, are both material and energy.

To reduce the level of energy pollution, mainly shielding of noise sources, electromagnetic fields and ionizing radiation, noise absorption, damping and dynamic vibration damping are used.

Sources of environmental pollution are subdivided into concentrated (point) and dispersed, as well as continuous and periodic action. Contaminants are also separated by persistent (indestructible) and destructible under the action of natural chemical and biological processes.

Production wastes include remnants of multicomponent natural raw materials after extraction of the target product from it, for example, empty ore rock, overburden from mining, slag and ash from thermal power plants, blast-furnace slags and burnt earth of metallurgical production flasks, metal shavings from machine-building enterprises, etc. In addition, they include significant waste from the forestry, woodworking, textile and other industries, road construction industry and the modern agro-industrial complex.

In industrial ecology, industrial waste is understood as waste that is in a solid state of aggregation. The same applies to consumer waste - industrial and domestic.

Consumption waste - products and materials that have lost their consumer properties as a result of physical (material) or moral deterioration. Industrial consumption waste includes machines, machine tools and other obsolete equipment of enterprises.

Household waste - waste generated as a result of human activity and disposed of by them as unwanted or useless.

A special category of waste (mainly industrial) is radioactive waste (RW) generated during the extraction, production and use of radioactive substances as fuel for nuclear power plants, vehicles (for example, nuclear submarines) and other purposes.

Toxic waste is a great threat to the environment, including some non-hazardous waste at the stage of its appearance, which acquires toxic properties during storage.

Chapter 2. Chemical pollution of the atmosphere

Atmospheric air is the most important life-supporting natural environment and is a mixture of gases and aerosols of the surface layer of the atmosphere, formed during the evolution of the Earth, human activities and located outside residential, industrial and other premises.

Air pollution is a change in its composition due to the intake of impurities of natural or anthropogenic origin. There are three types of pollutants: gases, aerosols and dust. Aerosols include dispersed solid particles emitted into the atmosphere and suspended in it for a long time.

The main air pollutants include carbon dioxide, carbon monoxide, sulfur and nitrogen dioxides, as well as trace gases that can affect the temperature regime of the troposphere: nitrogen dioxide, chlorofluorocarbons (freons), methane and tropospheric ozone.

The main contribution to the high level of air pollution is made by enterprises of ferrous and non-ferrous metallurgy, chemistry and petrochemistry, construction industry, energy, pulp and paper industry, and in some cities and boiler houses.

Atmospheric pollutants are divided into primary, entering directly into the atmosphere, and secondary, resulting from the transformation of the latter. So, sulfur dioxide entering the atmosphere is oxidized to sulfuric anhydride, which interacts with water vapor and forms droplets of sulfuric acid. When sulfuric anhydride interacts with ammonia, crystals of ammonium sulfate are formed. Similarly, as a result of chemical, photochemical, physicochemical reactions between pollutants and atmospheric components, other secondary signs are formed. The main source of pyrogenic pollution on the planet is thermal power plants, metallurgical and chemical enterprises, etc.

The main harmful impurities of pyrogenic (secondary) origin are the following:

1) carbon monoxide - obtained by incomplete combustion of carbonaceous substances. It gets into the air as a result of the incineration of solid waste, with exhaust gases and emissions from industrial enterprises. Annually, this gas enters the atmosphere at least 250 million tons. Carbon monoxide is a compound that actively reacts with the constituent parts of the atmosphere and contributes to an increase in the temperature on the planet and the creation of a greenhouse effect;

2) sulfurous anhydride - released during the combustion of sulfur-containing fuel or the processing of sulfur ores (up to 70 million tons per year). Some of the sulfur compounds are released during the combustion of organic residues in mining dumps. In the United States alone, the total amount of sulfur dioxide emitted to the atmosphere was 85 percent of the global emissions;

3) sulfuric anhydride - formed during the oxidation of sulfurous anhydride. The end product of the reaction is an aerosol or a solution of sulfuric acid in rainwater, which acidifies the soil and aggravates human respiratory tract diseases. The fallout of sulfuric acid aerosol from the smoke flares of chemical enterprises is noted at low cloudiness and high air humidity. Pyrometallurgical enterprises of non-ferrous and ferrous metallurgy, as well as thermal power plants, annually emit tens of millions of tons of sulfuric anhydride into the atmosphere;

4) hydrogen sulfide and carbon disulfide - enter the atmosphere separately or together with other sulfur compounds. The main sources of emissions are factories producing artificial fibers, sugar, coke-chemical, oil refineries and oil fields. In the atmosphere, when interacting with other pollutants, they undergo slow oxidation to sulfuric anhydride;

5) nitrogen oxides - the main sources of emissions are enterprises producing nitrogen fertilizers, nitric acid and nitrates, aniline dyes, nitro compounds, rayon silk, celluloid. The amount of nitrogen oxides released into the atmosphere is 20 million tons per year;

6) fluorine compounds - sources of pollution are enterprises producing aluminum, enamels, glass, ceramics, steel, phosphorus fertilizers. Fluorinated substances enter the atmosphere in the form of gaseous compounds - hydrogen fluoride or dust of sodium and calcium fluoride. The compounds are toxic. Fluoride derivatives are powerful insecticides.

7) chlorine compounds - enter the atmosphere from chemical enterprises producing hydrochloric acid, chlorine-containing pesticides, organic dyes, hydrolytic alcohol, bleach, soda. In the atmosphere, they are found as an admixture of chlorine molecules and hydrochloric acid vapors. Chlorine toxicity is determined by the type of compounds and their concentration.

The volume of emissions of pollutants into the atmosphere from stationary sources on the territory of Russia is about 22-25 million tons per year.

2.1 Aerosol pollution of the atmosphere and its impact on the ozone layer of the Earth

Aerosols are solid or liquid particles suspended in the air. In some cases, solid components of aerosols are especially dangerous for organisms, and in humans they cause specific diseases. In the atmosphere, aerosol pollution is perceived as smoke, fog, haze or haze. A significant part of aerosols is formed in the atmosphere when solid and liquid particles interact with each other or with water vapor.

Aerosols are divided into primary (emitted from pollution sources), secondary (formed in the atmosphere), volatile (transported over long distances), and non-volatile (deposited on the surface near the dust and gas emission zones). Stable and finely dispersed volatile aerosols (cadmium, mercury, antimony, iodine-131, etc.) tend to accumulate in lowlands, bays and other relief depressions, to a lesser extent on watersheds.

According to their origin, aerosols are divided into artificial and natural. Natural aerosols arise in natural conditions without human intervention, they enter the atmosphere during volcanic eruptions, the combustion of meteorites, during the occurrence of dust storms that lift particles of soil and rocks from the earth's surfaces, as well as during forest and steppe fires. During volcanic eruptions, black storms or fires, huge dust clouds are formed, which often spread over thousands of kilometers.

Regardless of the origin and formation conditions, an aerosol containing solid particles less than 5.0 microns in size is called smoke, and containing the smallest liquid particles is called fog.

The average size of aerosol particles is 1-5 microns. The Earth's atmosphere annually receives about 1 cubic meter. km of artificial dust particles. A large number of dust particles are also formed in the course of human production activities. The main sources of artificial aerosol air pollution are thermal power plants that consume high-ash coal, processing plants, metallurgical, cement, magnesite and soot plants. Aerosol particles from these sources have a wide variety of chemical compositions. Most often, they contain compounds of silicon, calcium and carbon, less often - metal oxides: iron, magnesium, manganese, zinc, copper, nickel, lead, antimony, bismuth, selenium, arsenic, beryllium, cadmium, chromium, cobalt, molybdenum, as well as asbestos. An even greater variety is characteristic of organic dust, including aliphatic and aromatic hydrocarbons, acid salts. It is formed during the combustion of residual oil products, in the process of pyrolysis at oil refineries.

Industrial dumps are constant sources of aerosol pollution - artificial embankments of redeposited material, mainly overburden, formed during the extraction of minerals or from waste of processing industry enterprises, thermal power plants. Mass blasting operations are the source of dust and poisonous gases. So, as a result of one medium-weight explosion (250-300 tons of explosives), about 2 thousand cubic meters are thrown into the atmosphere. m of conventional carbon monoxide and more than 150 tons of dust.

The production of cement and other building materials is also a source of dust pollution in the atmosphere. The main technological processes of these industries - grinding and chemical treatment of charges, semi-finished products and the resulting products in streams of hot gases are always accompanied by the emission of dust and other harmful substances into the atmosphere. Atmospheric pollutants include hydrocarbons - saturated and unsaturated, containing from 1 to 3 carbon atoms. They undergo various transformations, oxidation, polymerization, interacting with other atmospheric pollutants after being excited by solar radiation. As a result of these reactions, peroxide compounds, free radicals, hydrocarbon compounds with nitrogen and sulfur oxides are formed, often in the form of aerosol particles.

Aerosol pollution of the atmosphere disrupts the functioning of the ozone layer of the earth. The main hazard to atmospheric ozone is a group of chemicals called chlorofluorocarbons (CFCs), also called freons. For half a century, these chemicals, first produced in 1928, were considered miracles. They are non-toxic, inert, extremely stable, do not burn, do not dissolve in water, and are easy to manufacture and store. And therefore, the scope of CFCs has grown dynamically. CFCs have been used for over 60 years as refrigerants in refrigerators and air conditioning systems, as foaming agents in fire extinguishers, and in dry cleaning of clothing. Freons have proven to be very effective in cleaning parts in the electronics industry and are widely used in the production of foamed plastics. And with the beginning of the worldwide aerosol boom, they became most widespread (they were used as propellants for aerosol mixtures). Their world production peaked in 1987-1988. and amounted to about 1.2-1.4 million tons per year. industrial pollution smog atmosphere

The mechanism of action of freons is as follows. Getting into the upper layers of the atmosphere, these substances, inert near the surface of the Earth, become active. Under the influence of ultraviolet radiation, chemical bonds in their molecules are broken. As a result, chlorine is released, which, when it collides with an ozone molecule, "knocks out" one atom from it. Ozone ceases to be ozone, turning into oxygen. Chlorine, having temporarily combined with oxygen, again turns out to be free and "sets off in pursuit" for a new "victim". Its activity and aggressiveness is enough to destroy tens of thousands of ozone molecules.

Oxides of nitrogen, heavy metals (copper, iron, manganese), chlorine, bromine, fluorine also play an active role in the formation and destruction of ozone. Therefore, the overall ozone balance in the stratosphere is regulated by a complex set of processes in which about 100 chemical and photochemical reactions are significant.

In this balance, nitrogen, chlorine, oxygen, hydrogen and other components are involved as if in the form of catalysts, without changing their "content", therefore, the processes leading to their accumulation in the stratosphere or removal from it, significantly affect the ozone content. In this regard, the ingress of even relatively small amounts of such substances into the upper atmosphere can have a stable and long-term effect on the established balance associated with the formation and destruction of ozone.

Breaking the ecological balance, as life shows, is not difficult at all. It is immeasurably more difficult to restore it. Ozone-depleting substances are extremely stable: various types of freons, once in the atmosphere, can exist in it and do their destructive work from 75 to 100 years.

2.2 Photochemical fog (smog)

Photochemical smog or photochemical fog is a relatively new type of atmospheric pollution. It is an urgent environmental problem in the largest cities, where a huge number of vehicles are concentrated.

Photochemical smog is a multicomponent mixture of gases and aerosol particles. The main components of smog are ozone, oxides of sulfur and nitrogen, as well as numerous organic compounds of a peroxide nature, which are collectively called photooxidants.

Smog can form under almost any natural and climatic conditions in large cities and industrial centers with severe air pollution. Smog is most harmful during warm periods of the year, in sunny, calm weather, when the upper layers of the air are warm enough to stop the vertical circulation of air masses. This phenomenon often occurs in cities that are sheltered from the winds by natural barriers such as hills or mountains.

Photochemical smog occurs as a result of photochemical reactions under certain conditions: the presence of high concentrations of nitrogen oxides, hydrocarbons and other pollutants in the atmosphere. Intense solar radiation and calmness or very weak air exchange in the surface layer with a powerful and for at least a day increased inversion. Stable calm weather, usually accompanied by inversions, is necessary to create a high concentration of reactants. Such conditions are created more often in June-September and less often in winter. In prolonged clear weather, solar radiation causes the decomposition of nitrogen dioxide molecules to form nitric oxide and atomic oxygen.

Atomic oxygen with molecular oxygen gives ozone. It would seem that the latter, oxidizing nitric oxide, should again turn into molecular oxygen, and nitrogen oxide - into dioxide. But this is not happening. Nitric oxide reacts with olefins in the exhaust gases, which are split at the double bond and form molecular fragments and excess ozone. As a result of the ongoing dissociation, new masses of nitrogen dioxide are decomposed and give additional amounts of ozone. A cyclical reaction arises, as a result of which ozone gradually accumulates in the atmosphere. This process stops at night. In turn, ozone reacts with olefins. Various peroxides are concentrated in the atmosphere, which together form oxidants characteristic of photochemical fog. The latter are a source of so-called free radicals, which are particularly reactive. Such smogs are common over London, Paris, Los Angeles, New York and other cities in Europe and America. In terms of their physiological effect on the human body, they are extremely dangerous for the respiratory and circulatory systems and are often the cause of the premature death of city dwellers with poor health.

There are several types of smog, described above - dry smog, wet smog is characteristic of London, i.e. in the atmosphere, due to high humidity, droplets accumulate, which form thick clouds, but in Alaska, smog has been recorded, in which, due to the cold, small pieces of ice accumulate in the atmosphere instead of droplets.

The problem of photochemical smog is especially acute for countries such as the USA, Japan, Canada, Great Britain, Mexico, Argentina. For the first time, photochemical fog was recorded in 1944 in Los Angeles. The city is located in a depression surrounded by mountains and the sea, which leads to stagnation of air masses, accumulation of atmospheric pollutants and, as a result, favorable conditions for the formation of this type of smog.

At high concentrations of pollutants, photochemical smog can be observed as a bluish haze, which leads to reduced visibility, which disrupts transport. At lower concentrations, smog is a bluish or yellow-green haze rather than solid fog.

People, plants, buildings, and various materials suffer from photochemical smog. Photochemical fog irritates the mucous membranes of the eyes, nose and throat in humans. It exacerbates pulmonary and various chronic diseases, in addition, in addition to the irritating effect, it can also have a general toxic effect. Smog has an unpleasant odor.

Photochemical smog has a particularly bad effect on beans, beets, cereals, grapes, and ornamental plants. Leaf swelling is an indication that a plant has been damaged by photochemical fog, which then turns into spots and white bloom on the upper leaves, and leads to the appearance of a bronze or silvery shade on the lower leaves. Then the plant begins to wither quickly.

Among other things, photochemical fog leads to accelerated corrosion of materials and elements of buildings, cracking of paints, rubber and synthetic products, and even damage to clothing.

2.3 Maximum permissible concentration of emissions of harmful substances into the atmosphere

Maximum permissible concentrations (MPC) are those concentrations that, acting on a person and his offspring, directly or indirectly, do not worsen their working capacity, well-being, as well as sanitary and living conditions.

Generalization of all information on MPC, received by all departments, is carried out in the MGO - the Main Geophysical Observatory. In order to determine the air values from the observation results, the measured concentration values are compared with the maximum one-time maximum permissible concentration and the number of cases when the MPC was exceeded is determined, as well as how many times the maximum value was higher than the MPC. The average concentration value per month or per year is compared with the long-acting MPC - the medium-stable MPC.

The state of air pollution by several substances observed in the atmosphere of the city is assessed using a complex indicator - the air pollution index (API). For this, the MPCs normalized to the corresponding values and the average concentrations of various substances by means of simple calculations lead to the value of the concentrations of sulfur dioxide, and then they are summed up. The maximum one-time concentrations of the main pollutants were the highest in Norilsk (nitrogen and sulfur oxides), Frunze (dust), Omsk (carbon monoxide).

The degree of air pollution by the main pollutants is in direct proportion to the industrial development of the city. The highest maximum concentrations are typical for cities with a population of more than 500 thousand inhabitants. Air pollution with specific substances depends on the type of industry developed in the city.

The normative values of MPCs for pollutants in the atmospheric air of populated areas of Russia are approved by the decree of the Chief State Sanitary Doctor of the Russian Federation.

The MPC value is set taking into account various hazard indicators associated with the characteristics of the impact on the body or methods of transfer (exchange between media). In particular, to assess the MPC value for atmospheric air and natural waters used for water supply, an organoleptic indicator can be used that takes into account not only the toxic effect, but also the appearance of unpleasant sensations when inhaling polluted air or drinking polluted water.

For the most toxic substances, MPC values are not established. This means that any, even the most insignificant content of them in natural environments, pose a danger to human health. Some substances synthesized artificially and have no natural analogs can have such a high degree of toxicity.

The quality of atmospheric air is understood as the totality of the properties of the atmosphere, which determines the degree of influence of physical, chemical and biological factors on people, flora and fauna, as well as on materials, structures and the environment as a whole.

The permissible limits for the content of harmful substances are determined both in the production area (intended for the placement of industrial enterprises, pilot production facilities of research institutes, etc.), and in the residential area (intended for the placement of housing stock, public buildings and structures) of settlements. Basic terms and definitions concerning indicators of atmospheric pollution, observation programs, behavior of impurities in the atmospheric air are defined by GOST 17.2.1.03-84.

A feature of standardizing the quality of atmospheric air is the dependence of the impact of pollutants present in the air on the health of the population not only on the value of their concentrations, but also on the duration of the time interval during which a person breathes this air.

The maximum permissible concentration is the maximum one-time (MPCm.r.) - the maximum 20-30 minute concentration, when exposed to reflex reactions in humans (breath holding, irritation of the mucous membrane of the eyes, upper respiratory tract, etc.).

The maximum permissible average daily concentration (MPCss) is the concentration of a harmful substance in the air of populated areas, which should not have a direct or indirect effect on a person with unlimited long (years) inhalation. Thus, MPCss is calculated for all groups of the population and for an indefinitely long period of exposure and, therefore, is the most stringent sanitary and hygienic standard that establishes the concentration of a harmful substance in the air.

The maximum permissible concentration of a harmful substance in the air of the working area (MPCrz) is a concentration that, during daily (except weekends) work for 8 hours, or for another duration, but not more than 41 hours a week, throughout the entire working experience should not cause diseases or deviations in the state of health, detected by modern research methods, in the course of work or in the remote periods of life of the present and subsequent generations. The working area should be considered to be a space up to 2 m above the floor or area where there are places of permanent or temporary residence of workers.

As follows from the definition, MPCrz is a standard that limits the impact of a harmful substance on the adult working part of the population during the period of time established by labor legislation.

By the nature of the impact on the human body, harmful substances can be divided into groups:

Irritant (chlorine, ammonia, hydrogen chloride, etc.);

Choking (carbon monoxide, hydrogen sulfide, etc.); narcotic (nitrogen under pressure, acetylene, acetone, carbon tetrachloride, etc.);

Somatic, causing disturbances in the activity of the body (lead, benzene, methyl alcohol, arsenic).

Chapter 3. Main directions of atmospheric air protection

The main direction for the protection and protection of atmospheric air can be attributed to the introduction of waste-free production.

When creating waste-free industries, a number of complex organizational, technological, technical, economic and other problems are solved and a number of principles are used:

1. the principle of consistency. In accordance with it, each separate process or production is considered as an element of the dynamic system of all industrial production in the region.

2. the complexity of the use of resources. This principle requires the maximum use of all components of raw materials and the potential of energy resources. As you know, almost all raw materials are complex, and on average, more than a third of its amount is associated with elements that can be extracted only with its complex processing. So, already at present, almost all silver, bismuth, platinum and platinoids, as well as more than 20% of gold, are obtained along the way during the processing of complex ores. In Russia, this principle has been elevated to the rank of a state task and is clearly formulated in a number of government decrees.

3. the cyclical nature of material flows. The simplest examples of cyclical material flows include closed water and gas circulation cycles. As effective ways of forming cyclical material flows and rational use of energy, one can point to the combination and cooperation of industries, as well as the development and release of new types of products, taking into account the requirements of its reuse.

4. the principle of limited impact of production on the environment and social environment, taking into account the planned and purposeful growth of its volumes and environmental excellence. This principle is primarily associated with the preservation of such natural and social resources as atmospheric air, water, the Earth's surface, and public health. It should be borne in mind that the implementation of this principle is feasible only in combination with effective monitoring, developed environmental regulation and targeted nature management.

5. rationality of the organization of waste-free production. The decisive factors here are the requirement for the rational use of all components of raw materials, the maximum reduction of energy, material and labor intensity of production, the search for new environmentally sound raw materials and energy technologies, which is largely associated with a decrease in the negative impact on the environment and causing damage to it, including related industries. farms.

Among the many areas of creating low- and waste-free industries, the main ones are distinguished:

Integrated use of raw materials and energy resources;

Improvement of existing and development of fundamentally new technological processes and industries and related equipment;

Introduction of water and gas circulation cycles;

Application of continuous processes that allow the most efficient use of raw materials and energy;

Intensification of production processes, their optimization and automation;

Creation of power engineering processes.

At the federal level, the protection of atmospheric air is regulated by Law No. 96-FZ "On the Protection of Atmospheric Air". This law summarized the requirements developed in previous years and proven in practice. For example, the introduction of rules prohibiting the commissioning of any production facilities (newly created or reconstructed), if during operation they become sources of pollution or other negative effects on the atmospheric air. The rules on the regulation of maximum permissible concentrations of pollutants in the atmospheric air have been further developed.

Also, the law provides for requirements on the establishment of standards for maximum permissible emissions of pollutants into the atmosphere. Such standards are established for each stationary source of pollution, for each model of transport and other mobile vehicles and installations. They are determined in such a way that the total harmful emissions from all sources of pollution in a given area do not exceed the MPC standards for pollutants in the air. Maximum permissible emissions are established only taking into account the maximum permissible concentrations.

There are also architectural planning measures that are aimed at building enterprises, planning urban development taking into account environmental considerations, greening cities, etc. When building enterprises, it is necessary to adhere to the rules established by law and prevent the construction of hazardous industries in the city. It is necessary to carry out mass greening of cities, since green spaces absorb many harmful substances from the air and contribute to the purification of the atmosphere. Unfortunately, in the modern period in Russia, green spaces are not so much increasing as they are decreasing. Not to mention the fact that the "sleeping areas" built at one time do not stand up to criticism. Since in these areas, houses of the same type are located too densely (for the sake of saving space) and the air between them is prone to stagnation.

The law provides not only control over the fulfillment of its requirements, but also responsibility for their violation. A special article defines the role of public organizations and citizens in the implementation of measures for the protection of the air environment, obliges them to actively assist state bodies in these matters, since only broad public participation will make it possible to implement the provisions of this law. So, it says that the state attaches great importance to the preservation of a favorable state of atmospheric air, its restoration and improvement to ensure the best living conditions for people - their work, life, recreation and health protection.

Enterprises or their individual buildings and structures, the technological processes of which are a source of emission of harmful and unpleasant smelling substances into the atmospheric air, are separated from residential buildings by sanitary protection zones.

The sanitary protection zone for enterprises and facilities can be increased, if necessary and with proper justification, no more than 3 times, depending on the following reasons:

a) the effectiveness of the methods of purification of emissions into the atmosphere envisaged or possible for implementation;

b) lack of ways to clean up emissions;

c) placement of residential buildings, if necessary, on the leeward side in relation to the enterprise in the area of possible atmospheric pollution;

d) wind roses and other unfavorable local conditions (for example, frequent calm and fog);

e) construction of new, still insufficiently studied, sanitary production facilities.

The sizes of sanitary protection zones for individual groups or complexes of large enterprises of the chemical, oil refining, metallurgical, machine-building and other industries, as well as thermal power plants with emissions that create large concentrations of various harmful substances in the air and have a particularly adverse effect on health and sanitary hygienic living conditions of the population are established in each specific case by a joint decision of the Ministry of Health and the State Construction Committee of Russia.

To increase the efficiency of sanitary protection zones, tree-shrub and herbaceous vegetation is planted on their territory, which reduces the concentration of industrial dust and gases. In the sanitary protection zones of enterprises that intensively pollute the atmospheric air with gases harmful to vegetation, the most gas-resistant trees, shrubs and grasses should be grown, taking into account the degree of aggressiveness and concentration of industrial emissions. Emissions from chemical industry enterprises (sulfuric and sulfuric anhydride, hydrogen sulfide, sulfuric, nitric, fluoric and bromous acids, chlorine, fluorine, ammonia, etc.), ferrous and nonferrous metallurgy, coal and heat power industries are especially harmful to vegetation.

Conclusion

In the modern world, the problem of environmental pollution, in particular, atmospheric air, has become global. The task of preserving the environment, first of all, is facing the state, which at the federal level, with the help of state control instruments, takes all the necessary measures (setting standards, issuing laws and regulations). The introduction of low- and waste-free production also contributes to the rational use of resources and the reduction of emissions of harmful substances into the atmosphere.

However, an equally important task is to educate Russians about environmental awareness. The lack of elementary ecological thinking is especially noticeable at the present time. If in the West there are programs through the implementation of which the foundations of ecological thinking are laid in children from childhood, then in Russia there has not yet been significant progress in this area. Until a generation with a fully formed ecological consciousness appears in Russia, there will be no noticeable progress in understanding and preventing the environmental consequences of human activity.

List of used literature

1. Federal Law of 04.05.1999 No. 96-FZ "On the Protection of Atmospheric Air"

2. Yu.L. Khotuntsev "Man, technology, environment" - M .: Sustainable World (Library of the journal "Ecology and Life"), 2001 - 224 p.

3.http: //easytousetech.com/37-fotohimicheskiy-smog.html

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The science

The ever-increasing anthropogenic influence on nature and the growing scale of its pollution, gave impetus to the creation of a section of chemistry, called "Environmental Chemistry". Here the processes and transformations occurring in the soil, hydro- and atmosphere are studied, natural compounds and their origin are investigated. That is, the sphere of this section of scientific activity is chemical processes in the biosphere, the migration of elements and compounds along natural chains.

In turn, the chemistry of the environment has its own subsections. One studies the processes occurring in the lithosphere, the other - in the atmosphere, the third - in the hydrosphere. In addition, there are departments that study pollutants of natural and anthropogenic origin, their sources, transformations, movement, and so on. At the present time, another department has been created - an environmental department, the field of research of which is very close and sometimes identified with the general direction.

Environmental chemistry develops methods and means of protecting nature and is looking for ways to improve existing cleaning and disposal systems. This branch of chemistry is closely related to such areas of scientific research as ecology, geology, and so on.

It can be assumed that the largest source of environmental pollution is the chemical industry. But it is not so. Compared to other branches of industrial production, or transport, enterprises in this industry emit significantly less pollutants in terms of the amount of pollutants. However, the composition of these substances contains much more various chemical elements and compounds. These are organic solvents, amines, aldehydes, chlorine, oxides and much more. It was at chemical plants that xenobiotics were synthesized. That is, this industry pollutes nature with its production and produces products that are an independent source of pollution. That is, the sources of chemical pollution for the environment are both production, and products, and the results of their use.

Chemical science and industry, key branches of human activity. They investigate, develop, and then produce and use substances and compounds that serve as the basis for the structure of everything on Earth, including itself. The results of these activities have a real opportunity to influence the structure of living and nonliving matter, the stability of the existence of the biosphere, and the existence of life on the planet.

Types of pollution and their sources

Chemical pollution of the environment, as well as the corresponding branch of science, is conventionally divided into three types. Each species corresponds to a layer in the Earth's biosphere. These are chemical pollution: lithosphere, atmosphere and hydrosphere.

Atmosphere. The main sources of air pollution are: industry, transport and thermal power plants, including household boilers. In industrial production in terms of emissions of pollutants into the atmosphere, metallurgical plants, chemical enterprises and cement plants are in the lead. Substances pollute the air both when they first enter it and by derivatives that are formed in the atmosphere itself.

Hydrosphere. The main sources of pollution of the Earth's water basin are discharges from industrial enterprises, utilities, accidents and discharges of ships, runoff from agricultural lands, and so on. Pollutants are both organic and inorganic substances. The main ones include: compounds of arsenic, lead, mercury, inorganic acids and hydrocarbons in various forms and forms. Toxic heavy metals do not decompose and accumulate in organisms living in water. Oil and petroleum products pollute water both mechanically and chemically. By spreading a thin film over the surface of the water, they reduce the amount of light and oxygen in the water. As a result, the process of photosynthesis is slowed down, and decay is accelerated.

Lithosphere. The main sources of soil pollution are the household sector, industrial enterprises, transport, heat and power engineering and agriculture. As a result of their activity, heavy metals, pesticides, oil products, acid compounds and the like get into the ground. Changes in the chemical and physical composition of soils, as well as their structure, lead to a loss of productivity, erosion, destruction and weathering.

Environmental chemistry has information about more than 5 million types of compounds, and their number is constantly growing, which in one way or another "travel" through the biosphere. More than 60 thousand such compounds are involved in production activities.

Major pollutants and elements

Environmental chemistry considers the following elements and compounds as the main pollutants in nature.

Carbon monoxide is a colorless and odorless gas. An active compound that reacts with substances that make up the atmosphere. It underlies the formation of the "greenhouse effect". It is toxic and this property grows in the presence of nitrogen in the air.

Sulfur and sulfuric anhydride increase the acidity of the soil. Which leads to the loss of her fertility.

Hydrogen sulfide. Gas without color. Distinguished by the bright smell of rotten eggs. It is a reducing agent and oxidizes in air. It ignites at a temperature of 225 0 C. It is an accompanying gas in hydrocarbon deposits. It is present in volcanic gases, in mineral springs, and occurs at depths of more than 200 meters in the Black Sea. In nature, the source of its appearance is the decomposition of protein substances. In industrial production, it appears during the refining of oil and gas. It is used to obtain sulfur and sulfuric acid, various sulfur compounds, heavy water, in medicine. Hydrogen sulfide is toxic. It acts on mucous membranes and respiratory organs. If for most living organisms, it is a poisonous substance, then for some microorganisms and bacteria it is a habitat.

Nitrogen oxides. It is a colorless and odorless poisonous gas. Their danger grows in cities, where they mix with carbon and form photochemical smog. This gas has a negative effect on a person's respiratory tract and can lead to pulmonary edema. It is, together with sulfur oxide, a source of acid rain.

Sulfur dioxide. Colorless, pungent odor gas. Affects the mucous membrane of the eyes and respiratory system.

A negative impact on nature is caused by an increased content of fluorine, lead and chlorine compounds, hydrocarbons and their vapors, aldehydes and much more.

Substances designed and created to increase land fertility and crop productivity ultimately lead to soil degradation. The low degree of their assimilation at the places of application allows them to spread over considerable distances and "feed" completely different plants for which they are intended. The main medium for their movement is water. Accordingly, a significant increase in green mass is also observed in it. Water bodies overgrow and disappear.

Almost all "chemical" environmental pollutants have such a complex negative effect.

Until now, xenobiotics or artificially synthesized substances are classified as a separate category of pollutants. They do not end up in the usual cycle of food chains. There are also no effective ways of processing them in an artificial way. Xenobiotics accumulate in soil, water, air, living organisms. They migrate from body to body. How will this accumulation end and what is its critical mass?

The result of human impact on the environment, namely, his activity has generated the seemingly impossible pollution of nature with what it consists of, is a change in its root, deep composition and structure. The concentration of some chemical elements and a decrease in the volume of others, gives rise to unexplored and unpredictable, in terms of consequences, effects in the biosphere.