Air pollution in Moscow is due to the increased content of toxic impurities in the surface layer of Moscow air. It is caused by exhaust gases, emissions from industrial enterprises, emissions from thermal power plants. Every year, four times more people die from dirty air in Moscow than from car accidents - about 3,500 people.
It is especially dangerous to live in Moscow in complete calm. There are about 40 such days here every year. It is these days that doctors call "days of mortality" - after all, in one cube of Moscow air there are 7 milligrams of toxic substances. Here's another snack for you: every year, 1.3 million tons of poison are thrown into the air of Moscow.
Why are Muscovites dying?
Each Muscovite annually inhales more than 50 kilograms of various toxic substances. In year! In a special risk group, everyone who lives along the main streets, especially in apartments below the fifth floor. On the fifteenth floor, the concentration of poison is two times less, on the thirtieth, ten times less.
The main air poisoners in Moscow are nitrogen dioxide and carbon monoxide. It is they that give 90% of the entire palette of poisons in Moscow's surface air. These gases lead to asthma.
The next poisonous substance is sulfur dioxide. It is "supplied" by small Moscow and Moscow region boiler houses operating on liquid fuel. Sulfur dioxide leads to the deposition of plaques on the walls of blood vessels and to heart attacks. We should not forget that Muscovites most often die from cardiovascular diseases.
Next on the list of Moscow poison are suspended solids. These are fine dust (fine particles) up to 10 microns. They are more dangerous than any auto exhaust. They are formed from particles of tires, asphalt, technological exhausts.
Suspended substances with particles of poison adhering to them enter the lungs and remain there forever. When a certain critical mass accumulates in the lungs, lung diseases and lung cancer begin. It's almost 100% dead. Every year, 25,000 Muscovites die of cancer.
Vehicle emissions are the most dangerous in the field of ecology. Car exhausts are 80% of all the poison that the Moscow air receives. But this is not even the point - unlike thermal power plants and pipes of industrial enterprises, car exhausts are not produced at the height of factory pipes - tens of meters, but directly into our lungs.
A special risk group includes drivers who spend more than 3 hours a day on the roads of the capital. Indeed, in a car, the norms of maximum permissible concentrations are exceeded 10 times. Each car throws into the air in a year as many hordes as it weighs.
That is why living somewhere in Kapotnya or Lyublino is much less dangerous than in the most prestigious districts of Moscow. Indeed, on Tverskaya, on Ostozhenka, the traffic of cars is many times greater than on the industrial outskirts.
It is especially necessary to emphasize the concentration of toxic substances. Moscow is designed in such a way that it blows all the cinders to the south-east - it is here that the enchanted wind rose of Moscow sends all the poison. Not only that, the southeast of Moscow is also the lowest and coldest place in Moscow. And this means that the poisoned air from the center lingers here for a long time.
Air pollution in Moscow from thermal power plants
In the past year, the situation with the Moscow CHPP (however, as always) has deteriorated significantly. Moscow requires more and more electricity and heat, Moscow's thermal power plant provides the air of the capital with smoke and toxic substances. In general, in the energy system, the total fuel consumption increased by 1943 thousand tons, or almost 8%, compared to last year.
Basis of CHP emissions
- Carbon monoxide (carbon dioxide). Leads to lung disease and damage to the nervous system
- Heavy metals. Like other toxic substances, heavy metals are concentrated both in soils and in the human body. They never come out.
- suspended substances. They lead to lung cancer
- Sulphur dioxide. As already mentioned, sulfur dioxide leads to the deposition of plaques on the walls of blood vessels and to heart attacks.
Large CHPPs in Moscow:
- CHPP-8 address Ostapovsky proezd, house 1.
- CHP-9 address Avtozavodskaya, house 12, building 1.
- CHPP-11 address sh. Enthusiastov, house 32.
- CHPP-12 address Berezhkovskaya embankment, house 16.
- CHPP-16 address st. 3rd Khoroshevskaya, house 14.
- CHPP-20 address st. Vavilov, house 13.
- CHPP-21 address st. Izhorskaya, house 9.
- CHPP-23 address st. Mounting, house 1/4.
- CHPP-25 address st. Generala Dorokhova, house 16.
- CHPP-26 address st. Vostryakovsky proezd, house 10.
- CHPP-28 address st. Izhorskaya, house 13.
- CHPP-27 address Mytishchensky district, Chelobitevo village (outside the Moscow Ring Road)
- CHPP-22 address Dzerzhinsky st. Energetikov, house 5 (outside the Moscow Ring Road)
Air pollution in Moscow from waste incinerators
Look at the location of waste incinerators in Moscow:
In such areas, depending on the distance to the pipe:
- You can not be more than half an hour (300 meters to the pipes of the plant)
- It is impossible to stay for more than a day (five hundred meters to the pipes of the plant)
- It is impossible to live (kilometer to the pipes of the plant)
- The life of those living in this zone will be five years shorter (five kilometers to the plant's chimneys).
The most toxic substances on the planet are formed in the air - dioxins, carcinogenic compounds, heavy metals. Thus, the waste incineration plant in the Rudnevo industrial zone, which has a capacity greater than all other Moscow plants combined, is located in an area where there is an active construction of new buildings - near Lyubertsy.
This Moscow region was unlucky more than others - it is here that the Lyubertsy fields of aeration are located - a place where all the poison from the sewers of Moscow was poured for decades. It is here that mass construction of new buildings for deceived equity holders is underway.
The products of the incinerator are much more dangerous for humans than just waste, since all the waste that enters the incinerator comes in a “bound state”. After combustion, all poisons are released, including mercury and heavy metals. In addition, new types of harmful compounds appear - chlorine compounds, sulfur dioxide, nitrogen oxides - more than 400 compounds.
Moreover, only the most harmless substances - dust, ashes - are caught by traps. Whereas SO2, CO, NOx, HCl - that is, the main destroyers of health, practically cannot be filtered out.
Dioxins are much more difficult. Defenders of Moscow waste incineration plants claim that at 1000 degrees of combustion, dioxins burn out, but this is complete nonsense - when the temperature drops, dioxins rise again, and the higher the combustion temperature, the more nitrogen oxides.
And, finally, slags. Defenders of the MSZ argue that slags are absolutely safe and that cinder blocks should be made from them - to build houses. However, for some reason they themselves build houses from environmentally friendly materials.
It is a pity that MSZ lobbyists do not think that it is much more profitable to recycle waste - half of it is industrial methanol, which the industry readily buys, additional raw materials are received by the paper industry and a number of other industries.
Mortality in the areas of waste incinerators in Moscow
According to European scientists who have studied this topic, people exposed to incinerators have increased mortality:
- 3.5 times of lung cancer
- 1.7 times - from cancer of the esophagus
- 2.7 times from stomach cancer
- Child mortality has doubled
- The number of deformities in newborns increased by a quarter
Why you can't burn garbage in Moscow:
- There are no mercury lamps in the garbage abroad - we have them
- Reception of used batteries is organized abroad - everything is burned in our country
- In Europe and America, the processing of household appliances, paints and chemical waste is organized; at Moscow factories, all this burns with a blue flame.
Introduction 2
Atmospheric pollution 2
Sources of air pollution 3
Chemical pollution of the atmosphere 6
Aerosol pollution of the atmosphere 8
Photochemical mist 10
Earth's ozone layer 10
Air pollution from transport emissions 13
Measures to combat vehicle emissions 15
Means of protection of the atmosphere 17
Methods for cleaning gas emissions into the atmosphere 18
Atmospheric air protection 19
Conclusion 20
List of used literature 22
Introduction
The rapid growth of the human population and its scientific and technical equipment have radically changed the situation on Earth. If in the recent past all human activity manifested itself negatively only in limited, albeit numerous, territories, and the impact force was incomparably less than the powerful circulation of substances in nature, now the scales of natural and anthropogenic processes have become comparable, and the ratio between them continues to change with acceleration towards an increase in the power of anthropogenic influence on the biosphere.
The danger of unpredictable changes in the stable state of the biosphere, to which natural communities and species, including man himself, are historically adapted, is so great while maintaining the usual ways of managing that the current generations of people inhabiting the Earth have faced the task of urgently improving all aspects of their lives in accordance with the need preservation of the existing circulation of substances and energy in the biosphere. In addition, the widespread pollution of our environment with a variety of substances, sometimes completely alien to the normal existence of the human body, poses a serious danger to our health and the well-being of future generations.
Air pollution
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 activity and located outside residential, industrial and other premises. The results of environmental studies, both in Russia and abroad, unequivocally indicate that pollution of the surface atmosphere is the most powerful, constantly acting factor influencing humans, the food chain and the environment. Atmospheric air has an unlimited capacity and plays the role of the most mobile, chemically aggressive and all-penetrating agent of interaction near the surface of the components of the biosphere, hydrosphere and lithosphere.
In recent years, data have been obtained on the essential role of the ozone layer of the atmosphere for the preservation of the biosphere, which absorbs the ultraviolet radiation of the Sun, which is harmful to living organisms, and forms a thermal barrier at altitudes of about 40 km, which protects the cooling of the earth's surface.
The atmosphere has an intense impact not only on humans and biota, but also on the hydrosphere, soil and vegetation cover, geological environment, buildings, structures and other man-made objects. Therefore, the protection of atmospheric air and the ozone layer is the highest priority environmental problem and it is given close attention in all developed countries.
The polluted ground atmosphere causes cancer of the lungs, throat and skin, central nervous system disorders, allergic and respiratory diseases, birth defects and many other diseases, the list of which is determined by the pollutants present in the air and their combined effects on the human body. The results of special studies carried out in Russia and abroad have shown that there is a close positive relationship between the health of the population and the quality of atmospheric air.
The main agents of atmospheric influence on the hydrosphere are precipitation in the form of rain and snow, and to a lesser extent smog and fog. The surface and underground waters of the land are mainly atmospheric nourishment and, as a result, their chemical composition depends mainly on the state of the atmosphere.
The negative impact of the polluted atmosphere on the soil and vegetation cover is associated both with the precipitation of acid precipitation, which leaches calcium, humus and trace elements from the soil, and with the disruption of photosynthesis processes, leading to a slowdown in the growth and death of plants. The high sensitivity of trees (especially birch, oak) to air pollution has been identified for a long time. The combined action of both factors leads to a noticeable decrease in soil fertility and the disappearance of forests. Acid atmospheric precipitation is now considered as a powerful factor not only in the weathering of rocks and the deterioration of the quality of bearing soils, but also in the chemical destruction of man-made objects, including cultural monuments and land lines. Many economically developed countries are currently implementing programs to address the problem of acid precipitation. As part of the National Acid Rainfall Evaluation Program, established in 1980, many US federal agencies began funding research into the atmospheric processes that cause acid rain in order to assess the impact of the latter on ecosystems and develop appropriate conservation measures. It turned out that acid rain has a multifaceted impact on the environment and is the result of self-purification (washing) of the atmosphere. The main acidic agents are dilute sulfuric and nitric acids formed during the oxidation reactions of sulfur and nitrogen oxides with the participation of hydrogen peroxide.
Sources of air pollution
To natural sources pollution include: volcanic eruptions, dust storms, forest fires, dust of space origin, particles of sea salt, products of plant, animal and microbiological origin. The level of such pollution is considered as background, which changes little with time.
The main natural process of pollution of the surface atmosphere is the volcanic and fluid activity of the Earth. Large volcanic eruptions lead to global and long-term pollution of the atmosphere, as evidenced by the chronicles and modern observational data (the eruption of Mount Pinatubo in the Philippines in 1991). This is due to the fact that huge amounts of gases are instantly emitted into the high layers of the atmosphere, which are picked up by high-speed air currents at high altitude and quickly spread throughout the globe. The duration of the polluted state of the atmosphere after large volcanic eruptions reaches several years.
Anthropogenic sources pollution is caused by human activities. These should include:
1. Burning fossil fuels, which is accompanied by the release of 5 billion tons of carbon dioxide per year. As a result, over 100 years (1860 - 1960), the content of CO 2 increased by 18% (from 0.027 to 0.032%). Over the past three decades, the rates of these emissions have increased significantly. At such rates, by the year 2000 the amount of carbon dioxide in the atmosphere will be at least 0.05%.
2. The operation of thermal power plants, when acid rain is formed during the combustion of high-sulfur coals as a result of the release of sulfur dioxide and fuel oil.
3. Exhausts of modern turbojet aircraft with nitrogen oxides and gaseous fluorocarbons from aerosols, which can damage the ozone layer of the atmosphere (ozonosphere).
4. Production activity.
5. Pollution with suspended particles (when crushing, packing and loading, from boiler houses, power plants, mine shafts, quarries when burning garbage).
6. Emissions by enterprises of various gases.
7. Combustion of fuel in flare furnaces, resulting in the formation of the most massive pollutant - carbon monoxide.
8. Fuel combustion in boilers and vehicle engines, accompanied by the formation of nitrogen oxides, which cause smog.
9. Ventilation emissions (mine shafts).
10. Ventilation emissions with excessive ozone concentration from rooms with high energy installations (accelerators, ultraviolet sources and nuclear reactors) at MPC in working rooms of 0.1 mg/m 3 . In large quantities, ozone is a highly toxic gas.
During fuel combustion processes, the most intense pollution of the surface layer of the atmosphere occurs in megacities and large cities, industrial centers due to the wide distribution of vehicles, thermal power plants, boiler houses and other power plants operating on coal, fuel oil, diesel fuel, natural gas and gasoline. The contribution of vehicles to the total air pollution here reaches 40-50%. A powerful and extremely dangerous factor in atmospheric pollution are catastrophes at nuclear power plants (Chernobyl accident) and nuclear weapons tests in the atmosphere. This is due both to the rapid spread of radionuclides over long distances and to the long-term nature of the contamination of the territory.
The high danger of chemical and biochemical industries lies in the potential for accidental releases of extremely toxic substances into the atmosphere, as well as microbes and viruses that can cause epidemics among the population and animals.
Currently, many tens of thousands of pollutants of anthropogenic origin are found in the surface atmosphere. Due to the continued growth of industrial and agricultural production, new chemical compounds, including highly toxic ones, are emerging. The main anthropogenic air pollutants, in addition to large-tonnage oxides of sulfur, nitrogen, carbon, dust and soot, are complex organic, organochlorine and nitro compounds, man-made radionuclides, viruses and microbes. The most dangerous are dioxin, benz (a) pyrene, phenols, formaldehyde, and carbon disulfide, which are widespread in the air basin of Russia. Solid suspended particles are mainly represented by soot, calcite, quartz, hydromica, kaolinite, feldspar, less often sulfates, chlorides. Oxides, sulfates and sulfites, heavy metal sulfides, as well as alloys and metals in native form were found in snow dust by specially developed methods.
In Western Europe, priority is given to 28 especially dangerous chemical elements, compounds and their groups. The group of organic substances includes acrylic, nitrile, benzene, formaldehyde, styrene, toluene, vinyl chloride, anorganic substances - heavy metals (As, Cd, Cr, Pb, Mn, Hg, Ni, V), gases (carbon monoxide, hydrogen sulfide, nitrogen oxides and sulfur, radon, ozone), asbestos. Lead and cadmium are predominantly toxic. Carbon disulfide, hydrogen sulfide, styrene, tetrachloroethane, toluene have an intense unpleasant odor. The impact halo of sulfur and nitrogen oxides extends over long distances. The above 28 air pollutants are included in the international registry of potentially toxic chemicals.
The main indoor air pollutants are dust and tobacco smoke, carbon monoxide and carbon dioxide, nitrogen dioxide, radon and heavy metals, insecticides, deodorants, synthetic detergents, drug aerosols, microbes and bacteria. Japanese researchers have shown that bronchial asthma may be associated with the presence of domestic mites in the air of dwellings.
The atmosphere is characterized by extremely high dynamism, due to both the rapid movement of air masses in the lateral and vertical directions, and high speeds, a variety of physical and chemical reactions occurring in it. The atmosphere is now viewed as a huge "chemical cauldron" that is influenced by numerous and variable anthropogenic and natural factors. Gases and aerosols released into the atmosphere are highly reactive. Dust and soot generated during fuel combustion, forest fires absorb heavy metals and radionuclides and, when deposited on the surface, can pollute vast areas and enter the human body through the respiratory system.
The tendency of joint accumulation of lead and tin in solid suspended particles of the surface atmosphere of European Russia has been revealed; chromium, cobalt and nickel; strontium, phosphorus, scandium, rare earths and calcium; beryllium, tin, niobium, tungsten and molybdenum; lithium, beryllium and gallium; barium, zinc, manganese and copper. High concentrations of heavy metals in snow dust are due to both the presence of their mineral phases formed during the combustion of coal, fuel oil and other fuels, and the sorption of soot, clay particles of gaseous compounds such as tin halides.
The “lifetime” of gases and aerosols in the atmosphere varies over a very wide range (from 1–3 minutes to several months) and depends mainly on their chemical stability of size (for aerosols) and the presence of reactive components (ozone, hydrogen peroxide, etc.). .).
Estimating and even more so forecasting the state of the surface atmosphere is a very complex problem. At present, her condition is assessed mainly according to the normative approach. MPC values for toxic chemicals and other standard air quality indicators are given in many reference books and guidelines. In such guidelines for Europe, in addition to the toxicity of pollutants (carcinogenic, mutagenic, allergenic and other effects), their prevalence and ability to accumulate in the human body and the food chain are taken into account. The shortcomings of the normative approach are the unreliability of the accepted MPC values and other indicators due to the poor development of their empirical observational base, the lack of consideration for the combined effects of pollutants and abrupt changes in the state of the surface layer of the atmosphere in time and space. There are few stationary posts for monitoring the air basin, and they do not allow an adequate assessment of its condition in large industrial and urban centers. Needles, lichens, and mosses can be used as indicators of the chemical composition of the surface atmosphere. At the initial stage of revealing the centers of radioactive contamination associated with the Chernobyl accident, pine needles were studied, which have the ability to accumulate radionuclides in the air. Reddening of the needles of coniferous trees during periods of smog in cities is widely known.
The most sensitive and reliable indicator of the state of the surface atmosphere is the snow cover, which deposits pollutants over a relatively long period of time and makes it possible to determine the location of sources of dust and gas emissions using a set of indicators. Snowfall contains pollutants that are not captured by direct measurements or calculated data on dust and gas emissions.
One of the promising areas for assessing the state of the surface atmosphere of large industrial and urban areas is multichannel remote sensing. The advantage of this method lies in the ability to characterize large areas quickly, repeatedly and in the same way. To date, methods have been developed for estimating the content of aerosols in the atmosphere. The development of scientific and technological progress allows us to hope for the development of such methods in relation to other pollutants.
The forecast of the state of the surface atmosphere is carried out on the basis of complex data. These primarily include the results of monitoring observations, the patterns of migration and transformation of pollutants in the atmosphere, the features of anthropogenic and natural processes of pollution of the air basin of the study area, the influence of meteorological parameters, relief and other factors on the distribution of pollutants in the environment. For this purpose, heuristic models of changes in the surface atmosphere in time and space are developed for a specific region. The greatest success in solving this complex problem has been achieved for the areas where nuclear power plants are located. The end result of applying such models is a quantitative assessment of the risk of air pollution and an assessment of its acceptability from a socio-economic point of view.
Chemical pollution of the atmosphere
Atmospheric pollution should be understood as a change in its composition when impurities of natural or anthropogenic origin enter. There are three types of pollutants: gases, dust and aerosols. The latter include dispersed solid particles emitted into the atmosphere and suspended in it for a long time.
The main atmospheric pollutants include carbon dioxide, carbon monoxide, sulfur and nitrogen dioxide, as well as small gas components that can affect the temperature regime of the troposphere: nitrogen dioxide, halocarbons (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, boiler houses.
Sources of pollution - thermal power plants, which, together with smoke, emit sulfur dioxide and carbon dioxide into the air, metallurgical enterprises, especially non-ferrous metallurgy, which emit nitrogen oxides, hydrogen sulfide, chlorine, fluorine, ammonia, phosphorus compounds, particles and compounds of mercury and arsenic into the air; chemical and cement plants. Harmful gases enter the air as a result of fuel combustion for industrial needs, home heating, transport, combustion and processing of household and industrial waste.
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 reacts with ammonia, ammonium sulfate crystals are formed. Similarly, as a result of chemical, photochemical, physico-chemical reactions between pollutants and atmospheric components, other secondary signs are formed. The main source of pyrogenic pollution on the planet are thermal power plants, metallurgical and chemical enterprises, boiler plants that consume more than 170% of the annually produced solid and liquid fuels.
The main harmful impurities of pyrogenic origin are the following:
a) carbon monoxide. It is obtained by incomplete combustion of carbonaceous substances. It enters the air as a result of burning solid waste, with exhaust gases and emissions from industrial enterprises. At least 250 million tons of this gas enters the atmosphere every year. 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.
b) Sulfur dioxide. It is emitted during the combustion of sulfur-containing fuel or the processing of sulfurous ores (up to 70 million tons per year). Part of the sulfur compounds is released during the combustion of organic residues in mining dumps. In the United States alone, the total amount of sulfur dioxide emitted into the atmosphere amounted to 85 percent of the global emissions.
in) Sulfuric anhydride. It is formed during the oxidation of sulfur dioxide. The end product of the reaction is an aerosol or solution of sulfuric acid in rainwater, which acidifies the soil and exacerbates human respiratory diseases. The precipitation of sulfuric acid aerosol from smoke flares of chemical enterprises is observed 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.
G) Hydrogen sulfide and carbon disulfide. They enter the atmosphere separately or together with other sulfur compounds. The main sources of emissions are enterprises for the manufacture of artificial fiber, sugar, coke, oil refineries, and oil fields. In the atmosphere, when interacting with other pollutants, they undergo slow oxidation to sulfuric anhydride.
e) nitrogen oxides. The main sources of emissions are enterprises producing; nitrogen fertilizers, nitric acid and nitrates, aniline dyes, nitro compounds, viscose silk, celluloid. The amount of nitrogen oxides entering the atmosphere is 20 million tons per year.
e) Fluorine compounds. Sources of pollution are enterprises producing aluminum, enamels, glass, and ceramics. steel, phosphate fertilizers. Fluorine-containing substances enter the atmosphere in the form of gaseous compounds - hydrogen fluoride or dust of sodium and calcium fluoride. The compounds are characterized by a toxic effect. Fluorine derivatives are strong insecticides.
and) Chlorine compounds. They 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. The toxicity of chlorine is determined by the type of compounds and their concentration.
In the metallurgical industry, during the smelting of pig iron and its processing into steel, various heavy metals and toxic gases are released into the atmosphere. So, in terms of I tons of saturated cast iron, in addition to 2.7 kg of sulfur dioxide and 4.5 kg of dust particles, which determine the amount of compounds of arsenic, phosphorus, antimony, lead, mercury vapor and rare metals, tar substances and hydrogen cyanide, are released.
The volume of emissions of pollutants into the atmosphere from stationary sources in Russia is about 22 - 25 million tons per year.
Aerosol pollution of the atmosphere
Hundreds of millions of tons of aerosols enter the atmosphere from natural and anthropogenic sources every year. Aerosols are solid or liquid particles suspended in the air. Aerosols are divided into primary (those emitted from pollution sources), secondary (formed in the atmosphere), volatile (transported over long distances) and non-volatile (deposited on the surface near the zones of dust and gas emissions). Persistent 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.
Natural sources include dust storms, volcanic eruptions and forest fires. Gaseous emissions (eg SO 2) lead to the formation of aerosols in the atmosphere. Despite the fact that aerosols stay in the troposphere for several days, they can cause a decrease in the average air temperature near the earth's surface by 0.1 - 0.3C 0. No less dangerous for the atmosphere and biosphere are aerosols of anthropogenic origin, formed during the combustion of fuel or contained in industrial emissions.
The average size of aerosol particles is 1-5 microns. About 1 cubic meter enters the Earth's atmosphere every year. km of dust particles of artificial origin. A large number of dust particles are also formed during the production activities of people. Information about some sources of technogenic dust is given in table 1.
TABLE 1
MANUFACTURING PROCESS DUST EMISSIONS, MILLION. T/YEAR
1. Combustion of coal 93.6
2. Pig iron smelting 20.21
3. Copper smelting (without purification) 6.23
4. Smelting zinc 0.18
5. Smelting of tin (without cleaning) 0.004
6. Smelting lead 0.13
7. Cement production 53.37
The main sources of artificial aerosol air pollution are thermal power plants that consume high-ash coal, processing plants, and metallurgical plants. cement, magnesite and carbon black plants. Aerosol particles from these sources are distinguished by a wide variety of chemical composition. Most often, compounds of silicon, calcium and carbon are found in their composition, less often - oxides of metals: jelly, magnesium, manganese, zinc, copper, nickel, lead, antimony, bismuth, selenium, arsenic, beryllium, cadmium, chromium, cobalt, molybdenum, as well as asbestos. They are contained in emissions from thermal power plants, ferrous and non-ferrous metallurgy, building materials, and road transport. Dust deposited in industrial areas contains up to 20% iron oxide, 15% silicates and 5% soot, as well as impurities of various metals (lead, vanadium, molybdenum, arsenic, antimony, etc.).
An even greater variety is characteristic of organic dust, including aliphatic and aromatic hydrocarbons, acid salts. It is formed during the combustion of residual petroleum products, during the pyrolysis process at oil refineries, petrochemical and other similar enterprises. Permanent sources of aerosol pollution are industrial dumps - artificial mounds of redeposited material, mainly overburden, formed during mining or from waste from processing industries, thermal power plants. The source of dust and poisonous gases is mass blasting. So, as a result of one medium-sized explosion (250-300 tons of explosives), about 2 thousand cubic meters are released into the atmosphere. m of standard carbon monoxide and more than 150 tons of dust. The production of cement and other building materials is also a source of air pollution with dust. The main technological processes of these industries - grinding and chemical processing of charges, semi-finished products and products obtained in hot gas streams are always accompanied by emissions of dust and other harmful substances into the atmosphere.
The concentration of aerosols varies over a very wide range: from 10 mg/m3 in a clean atmosphere to 2.10 mg/m3 in industrial areas. The concentration of aerosols in industrial areas and large cities with heavy traffic is hundreds of times higher than in rural areas. Among aerosols of anthropogenic origin, lead is of particular danger to the biosphere, the concentration of which varies from 0.000001 mg/m 3 for uninhabited areas to 0.0001 mg/m 3 for residential areas. In cities, the concentration of lead is much higher - from 0.001 to 0.03 mg/m 3 .
Aerosols pollute not only the atmosphere, but also the stratosphere, affecting its spectral characteristics and causing a risk of damage to the ozone layer. Aerosols enter the stratosphere directly with emissions from supersonic aircraft, but there are aerosols and gases diffusing in the stratosphere.
The main aerosol of the atmosphere - sulfur dioxide (SO 2), despite the large scale of its emissions into the atmosphere, is a short-lived gas (4 - 5 days). According to modern estimates, at high altitudes, the exhaust gases of aircraft engines can increase the natural background of SO 2 by 20%. Although this figure is not large, an increase in the intensity of flights already in the 20th century may affect the albedo of the earth's surface in the direction of its increase. The annual release of sulfur dioxide into the atmosphere only as a result of industrial emissions is estimated at almost 150 million tons. Unlike carbon dioxide, sulfur dioxide is a very unstable chemical compound. Under the influence of short-wave solar radiation, it quickly turns into sulfuric anhydride and, in contact with water vapor, is converted into sulfurous acid. In a polluted atmosphere containing nitrogen dioxide, sulfur dioxide is quickly converted into sulfuric acid, which, when combined with water droplets, forms the so-called acid rain.
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, compounds of hydrocarbons with oxides of nitrogen and sulfur are formed, often in the form of aerosol particles. Under certain weather conditions, especially large accumulations of harmful gaseous and aerosol impurities can form in the surface air layer. This usually happens when there is an inversion in the air layer directly above the sources of gas and dust emission - the location of a layer of colder air under warm air, which prevents air masses and delays the transfer of impurities upward. As a result, harmful emissions are concentrated under the inversion layer, their content near the ground increases sharply, which becomes one of the reasons for the formation of a photochemical fog previously unknown in nature.
Photochemical fog (smog)
Photochemical fog is a multicomponent mixture of gases and aerosol particles of primary and secondary origin. The composition of the main components of smog includes ozone, nitrogen and sulfur oxides, numerous organic peroxide compounds, collectively called photooxidants. Photochemical smog occurs as a result of photochemical reactions under certain conditions: the presence in the atmosphere of a high concentration of nitrogen oxides, hydrocarbons and other pollutants; intense solar radiation and calm or very weak air exchange in the surface layer with a powerful and increased inversion for at least a day. Sustained 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 breakdown of nitrogen dioxide molecules with the formation of nitric oxide and atomic oxygen. Atomic oxygen with molecular oxygen give ozone. It would seem that the latter, oxidizing nitric oxide, should again turn into molecular oxygen, and nitric oxide into dioxide. But that doesn't happen. The nitric oxide reacts with the olefins in the exhaust gases, which break down the double bond to form molecular fragments and excess ozone. As a result of the ongoing dissociation, new masses of nitrogen dioxide are split and give additional amounts of ozone. A cyclic reaction occurs, 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 in total form oxidants characteristic of photochemical fog. The latter are the source of the so-called free radicals, which are characterized by a special reactivity. Such smog is not uncommon over London, Paris, Los Angeles, New York and other cities in Europe and America. According to their physiological effects on the human body, they are extremely dangerous for the respiratory and circulatory systems and often cause premature death of urban residents with poor health.
Earth's ozone layer
Earth's ozone layer – this is a layer of the atmosphere that closely coincides with the stratosphere, lying between 7 - 8 (at the poles), 17 - 18 (at the equator) and 50 km above the surface of the planet and is characterized by an increased concentration of ozone molecules that reflect hard cosmic radiation, fatal to all life on Earth . Its concentration at a height of 20 - 22 km from the Earth's surface, where it reaches a maximum, is negligible. This natural protective film is very thin: in the tropics it is only 2 mm thick, at the poles it is twice that.
The ozone layer actively absorbing ultraviolet radiation creates optimal light and thermal regimes of the earth's surface, favorable for the existence of living organisms on Earth. The concentration of ozone in the stratosphere is not constant, increasing from low latitudes to high latitudes, and is subject to seasonal changes with a maximum in spring.
The ozone layer owes its existence to the activity of photosynthetic plants (oxygen release) and to the action of ultraviolet rays on oxygen. It protects all life on Earth from the harmful effects of these rays.
It is assumed that global atmospheric pollution by certain substances (freons, nitrogen oxides, etc.) can disrupt the functioning of the Earth's ozone layer.
The main danger to atmospheric ozone is a group of chemicals grouped under the term "chlorofluorocarbons" (CFCs), also called freons. For half a century, these chemicals, first obtained in 1928, were considered miracle substances. They are non-toxic, inert, extremely stable, non-flammable, insoluble in water, easy to manufacture and store. And so the scope of CFCs has expanded dynamically. On a massive scale, they began to be used as refrigerants in the manufacture of refrigerators. Then they began to be used in air conditioning systems, and with the onset of the worldwide aerosol boom, they became the most widespread. Freons have proved to be very effective in washing parts in the electronics industry, and have also found wide application in the production of polyurethane foams. Their world production peaked in 1987-1988. and amounted to about 1.2 - 1.4 million tons per year, of which the US accounted for about 35%.
The mechanism of action of freons is as follows. Once in the upper layers of the atmosphere, these inert substances at the Earth's surface become active. Under the influence of ultraviolet radiation, the chemical bonds in their molecules are broken. As a result, chlorine is released, which, when colliding 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” of a new “victim”. Its activity and aggressiveness is enough to destroy tens of thousands of ozone molecules.
An active role in the formation and destruction of ozone is also played by oxides of nitrogen, heavy metals (copper, iron, manganese), chlorine, bromine, and fluorine. Therefore, the overall balance of ozone in the stratosphere is regulated by a complex set of processes in which about 100 chemical and photochemical reactions are significant. Taking into account the current gas composition of the stratosphere, in order to assess, we can say that about 70% of ozone is destroyed by the nitrogen cycle, 17 by oxygen, 10 by hydrogen, about 2 by chlorine and others, and about 1.2% enters troposphere.
In this balance, nitrogen, chlorine, oxygen, hydrogen and other components participate 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, even relatively small amounts of such substances entering the upper atmosphere can have a stable and long-term effect on the established balance associated with the formation and destruction of ozone.
Violating the ecological balance, as life shows, is not difficult at all. It is immeasurably more difficult to restore it. Ozone depleting substances are extremely resistant. Various types of freons, having entered the atmosphere, can exist in it and do their destructive work from 75 to 100 years.
Subtle at first, but accumulating changes in the ozone layer have led to the fact that in the Northern Hemisphere in the zone from 30 to 64 degrees north latitude since 1970, the total ozone content has decreased by 4% in winter and 1% in summer. Over Antarctica - and it was here that the "hole" in the ozone layer was first discovered - every polar spring a huge "hole" opens, every year it grows larger. If in 1990 - 1991. the size of the ozone "hole" did not exceed 10.1 million km 2, then in 1996, according to the bulletin of the World Meteorological Organization (WMO), its area was already 22 million km 2. This area is twice the area of Europe. The amount of ozone over the sixth continent was half the norm.
For more than 40 years, WMO has been monitoring the ozone layer over Antarctica. The phenomenon of the regular formation of "holes" just above it and the Arctic is explained by the fact that ozone is especially easily destroyed at low temperatures.
For the first time, the ozone anomaly in the Northern Hemisphere, unprecedented in its scale, "covering" a giant area from the coast of the Arctic Ocean to the Crimea, was recorded in 1994. The ozone layer was fading by 10 - 15%, and in some months - by 20 - 30%. However, even this - exceptional picture did not say that an even larger catastrophe was about to break out.
And, nevertheless, already in February 1995, scientists of the Central Aerological Observatory (CAO) of Roshydromet registered a catastrophic drop (by 40%) of ozone over the regions of Eastern Siberia. By mid-March, the situation became even more complicated. This meant only one thing - another ozone "hole" formed over the planet. However, today it is difficult to talk about the periodicity of the appearance of this "hole". Whether it will increase and what territory it will capture - this will be shown by observations.
In 1985, almost half of the ozone layer disappeared over Antarctica, and a “hole” appeared, which, two years later, spread over tens of millions of square kilometers and went beyond the sixth continent. Since 1986, ozone depletion has not only continued, but also sharply increased - it has evaporated 2-3 times faster than scientists predicted. In 1992, the ozone layer decreased not only over Antarctica, but also over other regions of the planet. In 1994, a giant anomaly was registered that captured the territories of Western and Eastern Europe, North Asia and North America.
If you delve into these dynamics, then one gets the impression that the atmospheric system has really gone out of balance and it is not known when it will stabilize. It is possible that ozone metamorphoses are to some extent a reflection of long-term cyclical processes, about which we know little. We do not have enough data to explain the current ozone pulsations. Perhaps they are of natural origin, and perhaps in time everything will settle down.
Many countries of the world are developing and implementing measures to implement the Vienna Conventions for the Protection of the Ozone Layer and the Montreal Protocol on Substances that Deplete the Ozone Layer.
What is the specificity of measures to preserve the ozone layer above the Earth?
According to international agreements, industrialized countries completely stop the production of freons and carbon tetrachloride, which also destroy ozone, and developing countries - by 2010. Russia, due to the difficult financial and economic situation, asked for a delay of 3-4 years.
The second stage should be a ban on the production of methyl bromides and hydrofreons. The level of production of the first in industrialized countries has been frozen since 1996, hydrofreons are completely removed from production by 2030. However, developing countries have not yet committed themselves to control these chemical substances.
An English environmental group called "Help the Ozone" hopes to restore the ozone layer over Antarctica by launching special balloons with ozone production units. One of the authors of this project stated that solar-powered ozone generators would be installed on hundreds of balloons filled with hydrogen or helium.
A few years ago, a technology was developed to replace freon with specially prepared propane. Now the industry has already reduced the production of aerosols using freons by a third. In the EEC countries, a complete cessation of the use of freons at household chemical plants, etc. is planned.
The depletion of the ozone layer is one of the factors causing global climate change on our planet. The consequences of this phenomenon, called the "greenhouse effect", are extremely difficult to predict. But scientists are also anxious about the possibility of changing the amount of precipitation, redistributing it between winter and summer, about the prospect of turning fertile regions into arid deserts, and raising the level of the World Ocean as a result of melting polar ice.
The growth of the harmful effects of ultraviolet radiation causes degradation of ecosystems and the gene pool of flora and fauna, reduces crop yields and the productivity of the oceans.
Air pollution from transport emissions
Car emissions account for a large share of air pollution. Now about 500 million cars are operated on Earth, and by the year 2000 their number is expected to increase to 900 million. In 1997, 2400 thousand cars were operated in Moscow, with the standard of 800 thousand cars for existing roads.
Currently, road transport accounts for more than half of all harmful emissions into the environment, which are the main source of air pollution, especially in large cities. On average, with a run of 15 thousand km per year, each car burns 2 tons of fuel and about 26 - 30 tons of air, including 4.5 tons of oxygen, which is 50 times more than human needs. At the same time, the car emits into the atmosphere (kg / year): carbon monoxide - 700, nitrogen dioxide - 40, unburned hydrocarbons - 230 and solids - 2 - 5. In addition, many lead compounds are emitted due to the use of mostly leaded gasoline .
Observations have shown that in houses located near the main road (up to 10 m), residents get cancer 3-4 times more often than in houses located at a distance of 50 m from the road. Transport also poisons water bodies, soil and plants.
Toxic emissions from internal combustion engines (ICE) are exhaust and crankcase gases, fuel vapors from the carburetor and fuel tank. The main share of toxic impurities enters the atmosphere with the exhaust gases of internal combustion engines. With crankcase gases and fuel vapors, approximately 45% of hydrocarbons from their total emission enter the atmosphere.
The amount of harmful substances entering the atmosphere as part of the exhaust gases depends on the general technical condition of the vehicles and, especially, on the engine - the source of the greatest pollution. So, if the carburetor adjustment is violated, carbon monoxide emissions increase by 4 ... 5 times. The use of leaded gasoline, which has lead compounds in its composition, causes air pollution with very toxic lead compounds. About 70% of lead added to gasoline with ethyl liquid enters the atmosphere with exhaust gases in the form of compounds, of which 30% settles on the ground immediately after the cut of the car's exhaust pipe, 40% remains in the atmosphere. One medium-duty truck releases 2.5...3 kg of lead per year. The concentration of lead in the air depends on the lead content in gasoline.
It is possible to exclude the entry of highly toxic lead compounds into the atmosphere by replacing leaded gasoline with unleaded.
The exhaust gases of gas turbine engines contain such toxic components as carbon monoxide, nitrogen oxides, hydrocarbons, soot, aldehydes, etc. The content of toxic components in combustion products significantly depends on the engine operating mode. High concentrations of carbon monoxide and hydrocarbons are typical for gas turbine propulsion systems (GTPU) at reduced modes (during idling, taxiing, approaching the airport, landing approach), while the content of nitrogen oxides increases significantly when operating at modes close to nominal (takeoff , climb, flight mode).
The total emission of toxic substances into the atmosphere by aircraft with gas turbine engines is constantly growing, which is due to an increase in fuel consumption up to 20...30 t/h and a steady increase in the number of aircraft in operation. The influence of GTDU on the ozone layer and the accumulation of carbon dioxide in the atmosphere is noted.
GGDU emissions have the greatest impact on living conditions at airports and areas adjacent to test stations. Comparative data on emissions of harmful substances at airports suggest that the revenues from gas turbine engines into the surface layer of the atmosphere are, %: carbon monoxide - 55, nitrogen oxides - 77, hydrocarbons - 93 and aerosol - 97. The rest of the emissions emit ground vehicles with internal combustion engines.
Air pollution by vehicles with rocket propulsion systems occurs mainly during their operation before launch, during takeoff, during ground tests during their production or after repair, during storage and transportation of fuel. The composition of combustion products during the operation of such engines is determined by the composition of the fuel components, the combustion temperature, and the processes of dissociation and recombination of molecules. The amount of combustion products depends on the power (thrust) of propulsion systems. During the combustion of solid fuels, water vapor, carbon dioxide, chlorine, hydrochloric acid vapor, carbon monoxide, nitrogen oxide, and solid Al 2 O 3 particles with an average size of 0.1 microns (sometimes up to 10 microns) are emitted from the combustion chamber.
When launched, rocket engines adversely affect not only the surface layer of the atmosphere, but also outer space, destroying the Earth's ozone layer. The scale of the destruction of the ozone layer is determined by the number of launches of rocket systems and the intensity of flights of supersonic aircraft.
In connection with the development of aviation and rocket technology, as well as the intensive use of aircraft and rocket engines in other sectors of the national economy, the total emission of harmful impurities into the atmosphere has increased significantly. However, these engines still account for no more than 5% of toxic substances entering the atmosphere from vehicles of all types.
Assessment of cars by exhaust toxicity. Day-to-day control of vehicles is of great importance. All fleets are required to monitor the serviceability of vehicles produced on the line. With a well-working engine, the carbon monoxide exhaust gases should contain no more than the permissible norm.
The regulation on the State Automobile Inspectorate is entrusted with monitoring the implementation of measures to protect the environment from the harmful effects of motor vehicles.
The adopted standard for toxicity provides for further tightening of the norm, although today in Russia they are tougher than European ones: for carbon monoxide - by 35%, for hydrocarbons - by 12%, for nitrogen oxides - by 21%.
The factories have introduced control and regulation of vehicles for toxicity and opacity of exhaust gases.
Urban transport management systems. New traffic control systems have been developed that minimize the possibility of traffic jams, because when stopping and then picking up speed, the car emits several times more harmful substances than when driving uniformly.
Highways were built to bypass the cities, which received the entire flow of transit transport, which used to be an endless tape along the city streets. The intensity of traffic has sharply decreased, the noise has decreased, the air has become cleaner.
An automated traffic control system "Start" has been created in Moscow. Thanks to perfect technical means, mathematical methods and computer technology, it allows you to optimally control the movement of traffic throughout the city and completely frees a person from the responsibility of directly regulating traffic flows. "Start" will reduce traffic delays at intersections by 20-25%, reduce the number of traffic accidents by 8-10%, improve the sanitary condition of urban air, increase the speed of public transport, and reduce noise levels.
Transfer of vehicles to diesel engines. According to experts, the transfer of vehicles to diesel engines will reduce the emission of harmful substances into the atmosphere. The exhaust of a diesel engine contains almost no toxic carbon monoxide, since diesel fuel is burned in it almost completely. In addition, diesel fuel is free of lead tetraethyl, an additive that is used to increase the octane rating of gasoline burned in modern high-burning carburetor engines.
Diesel is more economical than a carburetor engine by 20-30%. Moreover, the production of 1 liter of diesel fuel requires 2.5 times less energy than the production of the same amount of gasoline. Thus, it turns out, as it were, a double saving of energy resources. This explains the rapid growth in the number of vehicles running on diesel fuel.
Improvement of internal combustion engines. Creation of cars taking into account the requirements of ecology is one of the serious tasks that designers face today.
Improving the process of fuel combustion in an internal combustion engine, the use of an electronic ignition system leads to a decrease in the exhaust of harmful substances.
Neutralizers. Much attention is paid to the development of a device for reducing toxicity-neutralizers, which can be equipped with modern cars.
The method of catalytic conversion of combustion products is that the exhaust gases are cleaned by coming into contact with the catalyst. At the same time, afterburning of the products of incomplete combustion contained in the exhaust of cars takes place.
The converter is attached to the exhaust pipe, and the gases that have passed through it are released into the atmosphere purified. At the same time, the device can act as a noise suppressor. The effect of the use of neutralizers is impressive: in the optimal mode, the emission of carbon monoxide into the atmosphere is reduced by 70-80%, and hydrocarbons by 50-70%.
The composition of exhaust gases can be significantly improved by using various fuel additives. Scientists have developed an additive that reduces the content of soot in exhaust gases by 60-90% and carcinogens by 40%.
Recently, the process of catalytic reforming of low-octane gasolines has been widely introduced at the country's oil refineries. As a result, unleaded, low-toxic gasolines can be produced. Their use reduces air pollution, increases the service life of automobile engines, and reduces fuel consumption.
Gas instead of petrol. High-octane, compositionally stable gas fuel mixes well with air and is evenly distributed over the engine cylinders, contributing to a more complete combustion of the working mixture. The total emission of toxic substances from cars running on liquefied gas is much less than cars with gasoline engines. So, the ZIL-130 truck, converted to gas, has a toxicity indicator almost 4 times less than its gasoline counterpart.
When the engine is running on gas, the combustion of the mixture is more complete. And this leads to a decrease in the toxicity of exhaust gases, a decrease in carbon formation and oil consumption, and an increase in engine life. In addition, LPG is cheaper than gasoline.
Electric car. At present, when a car with a gasoline engine has become one of the significant factors leading to environmental pollution, experts are increasingly turning to the idea of creating a "clean" car. We are usually talking about an electric car.
Currently, five brands of electric vehicles are produced in our country. The electric car of the Ulyanovsk Automobile Plant (“UAZ” -451-MI) differs from other models by an alternating current electric propulsion system and a built-in charger. In the interests of protecting the environment, it is considered expedient to convert vehicles to electric traction, especially in large cities.
Means of protection of the atmosphere
Control of air pollution in Russia is carried out in almost 350 cities. The monitoring system includes 1200 stations and covers almost all cities with a population of more than 100 thousand inhabitants and cities with large industrial enterprises.
Means of protection of the atmosphere should limit the presence of harmful substances in the air of the human environment at a level not exceeding the MPC. In all cases, the condition must be met:
С+с f £MPC (1)
for each harmful substance (with f - background concentration).
Compliance with this requirement is achieved by localization of harmful substances at the place of their formation, removal from the room or equipment and dispersion in the atmosphere. If at the same time the concentration of harmful substances in the atmosphere exceeds the MPC, then the emissions are cleaned from harmful substances in the cleaning devices installed in the exhaust system. The most common are ventilation, technological and transport exhaust systems.
In practice, the following air protection options :
- removal of toxic substances from the premises by general ventilation;
- localization of toxic substances in the zone of their formation by local ventilation, purification of polluted air in special devices and its return to the production or domestic premises, if the air after cleaning in the device meets the regulatory requirements for supply air;
- localization of toxic substances in the area of their formation by local ventilation, purification of polluted air in special devices, release and dispersion in the atmosphere;
– purification of technological gas emissions in special devices, emission and dispersion in the atmosphere; in some cases, exhaust gases are diluted with atmospheric air before being released;
– purification of exhaust gases from power plants, for example, internal combustion engines in special units, and release into the atmosphere or production area (mines, quarries, storage facilities, etc.)
To comply with the MPC of harmful substances in the atmospheric air of populated areas, the maximum permissible emission (MAE) of harmful substances from exhaust ventilation systems, various technological and power plants is established.
Devices for cleaning ventilation and technological emissions into the atmosphere are divided into: dust collectors (dry, electric, filters, wet); mist eliminators (low and high speed); devices for capturing vapors and gases (absorption, chemisorption, adsorption and neutralizers); multi-stage cleaning devices (dust and gas traps, mists and solid impurities traps, multi-stage dust traps). Their work is characterized by a number of parameters. The main ones are cleaning activity, hydraulic resistance and power consumption.
Cleaning efficiency
h=( from in - from out)/with input (2)
where with input and from the exit- mass concentrations of impurities in the gas before and after the apparatus.
Dry dust collectors – cyclones of various types – have been widely used for gas purification of particles.
Electric cleaning (electrostatic precipitators) is one of the most advanced types of gas cleaning from dust and fog particles suspended in them. This process is based on the impact ionization of gas in the zone of the corona discharge, the transfer of the ion charge to impurity particles and the deposition of the latter on the collecting and corona electrodes. For this, electrofilters are used.
For highly efficient purification of emissions, it is necessary to use multi-stage purification devices. In this case, the gases to be purified pass successively several autonomous purification devices or one unit that includes several purification stages.
Such solutions are used in highly efficient gas purification from solid impurities; with simultaneous purification from solid and gaseous impurities; when cleaning from solid impurities and dropping liquid, etc. Multi-stage cleaning is widely used in air purification systems with its subsequent return to the room.
Methods for cleaning gas emissions into the atmosphere
absorption method gas purification, carried out in absorber units, is the simplest and provides a high degree of purification, but requires bulky equipment and purification of the absorbing liquid. Based on chemical reactions between a gas, such as sulfur dioxide, and an absorbent suspension (alkaline solution: limestone, ammonia, lime). With this method, gaseous harmful impurities are deposited on the surface of a solid porous body (adsorbent). The latter can be extracted by desorption by heating with water vapor.
Oxidation method combustible carbonaceous harmful substances in the air consists in combustion in a flame and the formation of CO 2 and water, the thermal oxidation method is in heating and feeding into a fire burner.
catalytic oxidation with the use of solid catalysts is that sulfur dioxide passes through the catalyst in the form of manganese compounds or sulfuric acid.
Reducing agents (hydrogen, ammonia, hydrocarbons, carbon monoxide) are used to purify gases by catalysis using reduction and decomposition reactions. Neutralization of nitrogen oxides NO x is achieved by using methane, followed by the use of aluminum oxide to neutralize the resulting carbon monoxide in the second stage.
promising sorption-catalytic method purification of especially toxic substances at temperatures below the temperature of catalysis.
Adsorption-oxidation method also seems promising. It consists in the physical adsorption of small amounts of harmful components, followed by the blowing of the adsorbed substance with a special gas flow into a thermocatalytic or thermal afterburning reactor.
In large cities, to reduce the harmful effects of air pollution on humans, special urban planning measures are used: zonal development of residential areas, when low buildings are located close to the road, then tall buildings and under their protection - children's and medical institutions; transport interchanges without intersections, landscaping.
Atmospheric air protection
Atmospheric air is one of the main vital elements of the environment.
The Law “O6 for the Protection of Atmospheric Air” comprehensively covers the problem. He summarized the requirements developed in previous years and justified themselves in practice. For example, the introduction of rules prohibiting the commissioning of any production facilities (newly created or reconstructed) if they become sources of pollution or other negative impacts on the atmospheric air during operation. The rules on the regulation of maximum permissible concentrations of pollutants in the atmospheric air were further developed.
The state sanitary legislation only for atmospheric air established MPCs for most chemicals with isolated action and for their combinations.
Hygienic standards are a state requirement for business leaders. Their implementation should be monitored by the state sanitary supervision bodies of the Ministry of Health and the State Committee for Ecology.
Of great importance for the sanitary protection of atmospheric air is the identification of new sources of air pollution, accounting for the designed, under construction and reconstructed facilities that pollute the atmosphere, control over the development and implementation of master plans for cities, towns and industrial centers in terms of the location of industrial enterprises and sanitary protection zones.
The Law "On the Protection of Atmospheric Air" provides for the requirements to establish standards for maximum permissible emissions of pollutants into the atmosphere. Such standards are established for each stationary source of pollution, for each model of vehicles 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 allowable emissions are set only taking into account the maximum allowable concentrations.
The requirements of the Law relating to the use of plant protection products, mineral fertilizers and other preparations are very important. All legislative measures constitute a preventive system aimed at preventing air pollution.
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 to protect 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. Thus, it says that the state attaches great importance to the preservation of the favorable state of atmospheric air, its restoration and improvement in order 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 the release of harmful and unpleasantly 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 properly justified, by no more than 3 times, depending on the following reasons: a) the effectiveness of the methods for cleaning emissions into the atmosphere provided or possible for implementation; b) lack of ways to clean emissions; c) placement of residential buildings, if necessary, on the leeward side in relation to the enterprise in the zone of possible air pollution; d) wind roses and other unfavorable local conditions (for example, frequent calms and fogs); e) the construction of new, still insufficiently studied, harmful in sanitary terms, industries.
Sizes of sanitary protection zones for individual groups or complexes of large enterprises in 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 Gosstroy of Russia.
To increase the effectiveness of sanitary protection zones, trees, shrubs 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. Particularly harmful to vegetation are emissions from chemical industries (sulphurous and sulfuric anhydride, hydrogen sulfide, sulfuric, nitric, fluoric and bromous acids, chlorine, fluorine, ammonia, etc.), ferrous and non-ferrous metallurgy, coal and thermal power industries.
Conclusion
The assessment and forecast of the chemical state of the surface atmosphere, associated with the natural processes of its pollution, differs significantly from the assessment and forecast of the quality of this natural environment, due to anthropogenic processes. Volcanic and fluid activity of the Earth, other natural phenomena cannot be controlled. We can only talk about minimizing the consequences of the negative impact, which is possible only in the case of a deep understanding of the functioning of natural systems of different hierarchical levels, and, above all, the Earth as a planet. It is necessary to take into account the interaction of numerous factors that change in time and space. The main factors include not only the internal activity of the Earth, but also its connections with the Sun and space. Therefore, thinking in "simple images" when assessing and predicting the state of the surface atmosphere is unacceptable and dangerous.
Anthropogenic processes of air pollution in most cases are manageable.
Environmental practice in Russia and abroad has shown that its failures are associated with incomplete consideration of negative impacts, inability to select and evaluate the main factors and consequences, low efficiency of using the results of field and theoretical environmental studies in decision-making, insufficient development of methods for quantifying the consequences of surface air pollution and other life-supporting natural environments.
All developed countries have laws on the protection of atmospheric air. They are periodically revised to take into account new air quality requirements and new data on the toxicity and behavior of pollutants in the air basin. In the United States, the fourth version of the Clean Air Act is now being discussed. The fight is between environmentalists and companies with no economic interest in improving air quality. The Government of the Russian Federation has developed a draft law on the protection of atmospheric air, which is currently being discussed. Improving air quality in Russia is of great social and economic importance.
This is due to many reasons, and, above all, the unfavorable state of the air basin of megacities, large cities and industrial centers, where the bulk of the skilled and able-bodied population lives.
It is easy to formulate a formula for the quality of life in such a protracted ecological crisis: hygienically clean air, clean water, high-quality agricultural products, recreational provision of the needs of the population. It is more difficult to realize this quality of life in the presence of an economic crisis and limited financial resources. In such a formulation of the question, research and practical measures are needed, which form the basis of the "greening" of social production.
The environmental strategy, first of all, implies a reasonable environmentally sound technological and technical policy. This policy can be formulated briefly: to produce more with less, i.e. save resources, use them with the greatest effect, improve and quickly change technologies, introduce and expand recycling. In other words, a strategy of preventive environmental measures should be provided, which consists in the introduction of the most advanced technologies in the restructuring of the economy, providing energy and resource saving, opening up opportunities for improving and rapidly changing technologies, introducing recycling and minimizing waste. At the same time, the concentration of efforts should be aimed at developing the production of consumer goods and increasing the share of consumption. On the whole, the Russian economy should reduce as much as possible the energy and resource intensity of the gross national product and the consumption of energy and resources per capita. The market system itself and competition should facilitate the implementation of this strategy.
The protection of nature is the task of our century, a problem that has become a social one. Again and again we hear about the danger threatening the environment, but still many of us consider them an unpleasant, but inevitable product of civilization and believe that we will still have time to cope with all the difficulties that have come to light. However, human impact on the environment has taken on alarming proportions. To fundamentally improve the situation, purposeful and thoughtful actions will be needed. A responsible and efficient policy towards the environment will be possible only if we accumulate reliable data on the current state of the environment, substantiated knowledge about the interaction of important environmental factors, if we develop new methods to reduce and prevent the harm caused to Nature by Man.
The time is already coming when the world can suffocate if Man does not come to the aid of Nature. Only Man has an ecological talent - to keep the world around us clean.
List of used literature:
1. Danilov-Danilyan V.I. "Ecology, nature conservation and environmental safety" M.: MNEPU, 1997
2. Protasov V.F. "Ecology, health and environmental protection in Russia", Moscow: Finance and statistics, 1999
3. Belov S.V. "Life safety" M .: Higher school, 1999
4. Danilov-Danilyan V.I. "Environmental problems: what is happening, who is to blame and what to do?" M.: MNEPU, 1997
5. Kozlov A.I., Vershubskaya G.G. "Medical Anthropology of the Indigenous Population of the North of Russia" M.: MNEPU, 1999
For these purposes, standards are being developed that limit the content of the most dangerous pollutants, both in the atmospheric air and in pollution sources. The minimum concentration that causes an initial typical exposure is called the threshold concentration.
To assess air pollution, comparative criteria for the content of impurities are used; according to GOST, these are substances that are absent in the composition of the atmosphere. The air quality standards are Approximate Safe Exposure Levels (SEL) and Approximate Permissible Concentrations (AEC). Instead of OBUV and AEC, the values of temporarily permissible concentrations (VDC) are used.
The main indicator in the Russian Federation is the indicator of the maximum permissible concentration of harmful substances (MPC), which has become widespread since 1971. MPCs are the upper maximum permissible concentrations of substances at which their content does not go beyond the boundaries of the human ecological niche. The maximum allowable concentration (MAC) of a gas, vapor or dust is considered to be the concentration that is tolerated without any consequences during daily inhalation during the working day and long-term constant exposure.
In practice, there is a separate rationing of the content of impurities: in the air of the working area (MPC.z) and in the atmospheric air of the settlement (MPC.v). MPC.v is the maximum concentration of a substance in the atmosphere that does not have a harmful effect on humans and the environment, MPCr.z is the concentration of a substance in the working area, causing a disease when working no more than 41 hours a week. The working area is understood as a working room (room). It also provides for the division of MPC into maximum one-time (MPCm.r) and average daily (MPCs.s). All concentrations of impurities in the air of the working area are compared with the maximum one-time (within 30 minutes), and for the settlement with the average daily (for 24 hours). Usually, the used symbol MPKr.z refers to the maximum one-time MPC in the working area, and MPCm.r is the concentration in the air of the residential area. Usually MPCr.z.> MPCm.r, i.e. in fact MPKr.z>MPKr.v. For example, for sulfur dioxide MPCr.z=10 mg/m 3 , and MPCm.r=0.5 mg/m 3 .
A lethal (lethal) concentration or dose (LC 50 and LD 50) is also established, at which the death of half of the experimental animals is observed.
Table 3
Hazard classes of chemical pollutants depending on some toxicometric characteristics (G.P. Bespamyatnov. Yu.A. Krotov. 1985)
The standards provide for the possibility of exposure to several substances at the same time, in this case they talk about the effect of the summation of harmful effects (the effect of the summation of phenol and acetone; valeric, caproic and butyric acids; ozone, nitrogen dioxide and formaldehyde). The list of substances with the summation effect is given in the appendix. A situation may arise when the ratio of the concentration of an individual substance to the MPC is less than one, but the total concentration of substances will be higher than the MPC of each of the substances and the total pollution will exceed the permissible level.
Within the limits of industrial sites, according to SN 245-71, emissions into the atmosphere should be limited, taking into account the fact that, taking into account dispersion, the concentration of substances at the industrial site did not exceed 30% of the MPC.z., and in the residential area no more than 80% of the MPCm.r.
Compliance with all these requirements is controlled by sanitary and epidemiological stations. Currently, in most cases, it is impossible to limit the content of impurities to MPC at the outlet of the emission source, and separate regulation of permissible levels of pollution takes into account the effect of mixing and dispersion of impurities in the atmosphere. Regulation of emissions of harmful substances into the atmosphere is carried out on the basis of the establishment of maximum allowable emissions (MAE). In order to regulate emissions, one should first determine the maximum possible concentration of harmful substances (Cm) and the distance (Um) from the source of the emission, where this concentration occurs.
The value of C should not exceed the established MPC values.
According to GOST 17.2.1.04-77, the maximum allowable emission (MAE) of a harmful substance into the atmosphere is a scientific and technical standard that provides that the concentration of pollutants in the surface air layer from a source or their combination does not exceed the standard concentration of these substances that worsen air quality. The dimension of MPE is measured in (g/s). MPE should be compared with the emission rate (M), i.e. the amount of substance emitted per unit of time: M=CV g/s.
MPE is set for each source and should not create surface concentrations of harmful substances that exceed the MAC. MPE values are calculated on the basis of MPC and the maximum concentration of a harmful substance in the atmospheric air (Cm). The calculation method is given in SN 369-74. Sometimes Temporarily Agreed Emissions (TAEs) are introduced, which are determined by the line ministry. In the absence of MPC, such an indicator as SHEV is often used - an approximate safe level of exposure to a chemical in the atmospheric air, established by calculation (temporary standard - for 3 years).
Maximum allowable emissions (MAE) or emission limits have been established. For enterprises, their individual buildings and structures with technological processes that are sources of industrial hazard, a sanitary classification is provided that takes into account the capacity of the enterprise, the conditions for the implementation of technological processes, the nature and amount of harmful and unpleasantly smelling substances released into the environment, noise, vibration, electromagnetic waves, ultrasound and other harmful factors, as well as providing for measures to reduce the adverse impact of these factors on the environment.
A specific listing of the production facilities of chemical enterprises with assignment to the corresponding class is given in the Sanitary Design Standards for Industrial Enterprises SN 245-71. There are five classes of enterprises in total.
In accordance with the sanitary classification of enterprises, industries and facilities, the following sizes of sanitary protection zones have been adopted:
If necessary and with appropriate justification, the sanitary protection zone can be increased, but not more than 3 times. An increase in the sanitary protection zone is possible, for example, in the following cases:
· with low efficiency of systems for purification of emissions into the atmosphere;
in the absence of ways to clean up emissions;
· if it is necessary to place residential buildings on the leeward side in relation to the enterprise, in the zone of possible air pollution;
The process of pollution with toxic substances is created not only by industrial enterprises, but also by the entire life cycle of industrial products, i.e. from raw material preparation, energy production and transportation, to the use of industrial products and their disposal or storage in landfills. Many industrial pollutants come from transboundary transport from industrial areas of the world. Based on the results of the environmental analysis of the production cycles of various industries, as well as individual products, it is necessary to change the structure of industrial activities and consumer habits. Industry in Russia and Eastern Europe needs a radical modernization, and not just new technologies for cleaning emissions and effluents. Only technically advanced and competitive enterprises are able to solve emerging environmental problems.
For the technologically advanced countries of Europe, one of the main problems is to reduce the amount of household waste due to their more efficient collection, sorting and processing or environmentally competent disposal of waste.
The problem of environmental friendliness of cars arose in the middle of the twentieth century, when cars became a mass product. European countries, being in a relatively small area, earlier than others began to apply various environmental standards. They existed in individual countries and included various requirements for the content of harmful substances in the exhaust gases of cars.
In 1988, the United Nations Economic Commission for Europe introduced a single regulation (the so-called Euro-0) with requirements to reduce the level of emissions of carbon monoxide, nitrogen oxide and other substances in cars. Once every few years, the requirements became tougher, other states also began to introduce similar standards.
Environmental regulations in Europe
Since 2015, Euro-6 standards have been in force in Europe. According to these requirements, the following permissible emissions of harmful substances (g / km) are established for gasoline engines:
- Carbon monoxide (CO) - 1
- Hydrocarbon (CH) - 0.1
- Nitric oxide (NOx) - 0.06
For vehicles with diesel engines, the Euro 6 standard establishes other standards (g / km):
- Carbon monoxide (CO) - 0.5
- Nitric oxide (NOx) - 0.08
- Hydrocarbons and nitrogen oxides (HC + NOx) - 0.17
- Suspended particles (PM) - 0.005
Environmental standard in Russia
Russia follows the EU standards for exhaust emissions, although their implementation is 6-10 years behind. The first standard that was officially approved in the Russian Federation was Euro-2 in 2006.
Since 2014, the Euro-5 standard has been in force in Russia for imported cars. Since 2016, it has been applied to all manufactured cars.
The Euro 5 and Euro 6 standards have the same maximum emission limits for vehicles with a gasoline engine. But for cars whose engines run on diesel fuel, the Euro-5 standard has less stringent requirements: nitrogen oxide (NOx) should not exceed 0.18 g / km, and hydrocarbons and nitrogen oxides (HC + NOx) - 0.23 g/km.
US emission standards
The U.S. Federal Air Emission Standard for passenger cars is divided into three categories: Low Emission Vehicles (LEV), Ultra Low Emission Vehicles (ULEV - Hybrids), and Super Low Emission Vehicles (SULEV - Electric Vehicles). Each class has separate requirements.
In general, all manufacturers and dealers selling cars in the United States adhere to the requirements for emissions into the atmosphere of the EPA agency (LEV II):
|
Mileage (miles) |
Non-methane organic gases (NMOG), g/mi |
Nitric oxide (NO x), g/mi |
Carbon monoxide (CO), g/mi |
Formaldehyde (HCHO), g/mi |
Particulate matter (PM) |
|
|---|---|---|---|---|---|---|
Emission standards in China
In China, vehicle emission control programs began to emerge in the 1980s, and a national standard did not emerge until the late 1990s. China has begun to gradually implement strict exhaust emission standards for passenger cars in line with European regulations. China-1 became the equivalent of Euro-1, China-2 became Euro-2, etc.
China's current national automotive emission standard is China-5. It sets different standards for two types of vehicles:
- Type 1 vehicles: vehicles with a maximum of 6 passengers, including the driver. Weight ≤ 2.5 tons.
- Type 2 vehicles: other light vehicles (including light trucks).
According to the China-5 standard, emission limits for gasoline engines are as follows:
|
Vehicle type |
Weight, kg |
Carbon monoxide (CO), |
Hydrocarbons (HC), g/km |
Nitric oxide (NOx), g/km |
Particulate matter (PM) |
|---|---|---|---|---|---|
Diesel vehicles have different emission limits:
|
Vehicle type |
Weight, kg |
Carbon monoxide (CO), |
Hydrocarbons and nitrogen oxides (HC + NOx), g/km |
Nitric oxide (NOx), g/km |
Particulate matter (PM) |
|---|---|---|---|---|---|
Emission regulations in Brazil
Brazil's motor vehicle emissions control program is called PROCONVE. The first standard was introduced in 1988. In general, these standards correspond to European ones, but the current PROCONVE L6, although it is an analogue of Euro-5, does not include the mandatory presence of filters for filtering particulate matter or the amount of emissions into the atmosphere.
For vehicles weighing less than 1700 kg, the PROCONVE L6 emission standards are as follows (g/km):- Carbon monoxide (CO) - 2
- Tetrahydrocannabinol (THC) - 0.3
- Volatile organic substances (NMHC) - 0.05
- Nitric oxide (NOx) - 0.08
- Suspended particles (PM) - 0.03
If the mass of the car is more than 1700 kg, then the norms change (g / km):
- Carbon monoxide (CO) - 2
- Tetrahydrocannabinol (THC) - 0.5
- Volatile organic substances (NMHC) - 0.06
- Nitric oxide (NOx) - 0.25
- Suspended particles (PM) - 0.03.
Where are the stricter rules?
In general, developed countries are guided by similar standards for the content of harmful substances in exhaust gases. In this regard, the European Union is a kind of authority: it most often updates these indicators and introduces strict legal regulation. Other countries are following this trend and are also updating their emission standards. For example, the Chinese program is fully equivalent to the Euro: the current China-5 corresponds to Euro-5. Russia is also trying to keep up with the European Union, but at the moment the standard that was in force in European countries until 2015 is being implemented.
Industrial and economic development is accompanied, as a rule, by an increase in environmental pollution. Most large cities are characterized by a significant concentration of industrial facilities in relatively small areas, which poses a risk to human health.
One of the environmental factors that have the most pronounced impact on human health is air quality. Emissions of pollutants into the atmosphere present a particular danger. This is due to the fact that toxicants enter the human body mainly through the respiratory tract.
Air Emissions: Sources
Distinguish between natural and anthropogenic sources of pollutants in the air. The main impurities that contain atmospheric emissions from natural sources are dust of cosmic, volcanic and vegetable origin, gases and smoke resulting from forest and steppe fires, products of destruction and weathering of rocks and soils, etc.
The levels of air pollution by natural sources are of a background nature. They change little over time. The main sources of pollutants entering the air basin at the present stage are anthropogenic, namely, industry (various industries), agriculture and motor transport.
Emissions from enterprises into the atmosphere
The largest "suppliers" of various pollutants to the air basin are metallurgical and energy enterprises, chemical production, the construction industry, and mechanical engineering.
In the process of burning fuels of various types by energy complexes, large amounts of sulfur dioxide, carbon and nitrogen oxides, and soot are released into the atmosphere. A number of other substances are also present in emissions (in smaller quantities), in particular hydrocarbons.
The main sources of dust and gas emissions in metallurgical production are melting furnaces, pouring plants, pickling departments, sintering machines, crushing and grinding equipment, unloading and loading of materials, etc. The largest share among the total amount of substances entering the atmosphere is carbon monoxide, dust, sulfur dioxide, nitrogen oxide. Manganese, arsenic, lead, phosphorus, mercury vapours, etc. are emitted in somewhat smaller quantities. Also, in the process of steelmaking, emissions into the atmosphere contain vapor-gas mixtures. They include phenol, benzene, formaldehyde, ammonia and a number of other hazardous substances.
Harmful emissions into the atmosphere from enterprises of the chemical industry, despite their small volumes, pose a particular danger to the environment and humans, since they are characterized by high toxicity, concentration and considerable diversity. The mixtures entering the air, depending on the type of products produced, may contain volatile organic compounds, fluorine compounds, nitrous gases, solids, chloride compounds, hydrogen sulfide, etc.
In the production of building materials and cement, emissions into the atmosphere contain significant amounts of various dusts. The main technological processes leading to their formation are grinding, processing of batches, semi-finished products and products in hot gas flows, etc. Contamination zones with a radius of up to 2000 m can form around plants that produce various building materials. They are characterized by a high concentration of dust in the air containing particles of gypsum, cement, quartz, and a number of other pollutants.
Vehicle emissions
In large cities, a huge amount of pollutants into the atmosphere comes from motor vehicles. According to various estimates, they account for 80 to 95%. consist of a large number of toxic compounds, in particular nitrogen and carbon oxides, aldehydes, hydrocarbons, etc. (about 200 compounds in total).
Emissions are highest at traffic lights and intersections, where vehicles are moving at low speeds and idling. The calculation of emissions into the atmosphere shows that the main components of the emissions in this case are also hydrocarbons.
At the same time, it should be noted that, unlike stationary sources of emissions, the operation of vehicles leads to air pollution on city streets at the height of human growth. As a result, pedestrians, residents of houses located along the roads, as well as vegetation growing in adjacent areas are exposed to the harmful effects of pollutants.
Agriculture
Impact on a person
According to various sources, there is a direct link between air pollution and a number of diseases. So, for example, the duration of the course of respiratory diseases in children who live in relatively polluted areas is 2-2.5 times longer than in those who live in other areas.
In addition, in cities characterized by unfavorable environmental conditions, children showed functional deviations in the system of immunity and blood formation, violations of compensatory-adaptive mechanisms to environmental conditions. Many studies have also found a link between air pollution and human mortality.
The main components of air emissions from various sources are suspended solids, oxides of nitrogen, carbon and sulfur. It was revealed that the zones with exceeding the MPC for NO 2 and CO cover up to 90% of the urban area. These macro-components of emissions can cause serious diseases. The accumulation of these contaminants leads to damage to the mucous membranes of the upper respiratory tract, the development of pulmonary diseases. In addition, elevated concentrations of SO 2 can cause dystrophic changes in the kidneys, liver and heart, and NO 2 - toxicosis, congenital anomalies, heart failure, nervous disorders, etc. Some studies have found a relationship between the incidence of lung cancer and the concentrations of SO 2 and NO 2 in the air.
conclusions
Pollution of the environment and, in particular, the atmosphere, has adverse effects on the health of not only the present, but also future generations. Therefore, we can safely say that the development of measures aimed at reducing emissions of harmful substances into the atmosphere is one of the most urgent problems of mankind today.
