Problems of atmospheric air pollution by industrial enterprises. Atmospheric air pollution by industrial emissions

Atmospheric pollution The atmosphere is the air envelope of the Earth. The quality of the atmosphere is understood as the totality of its properties that determine the degree of impact of physical, chemical and biological factors on people, flora and fauna, as well as on materials, structures and the environment as a whole. Atmospheric pollution is understood as the introduction of impurities into it that are not contained in natural air or change the ratio between the ingredients of the natural composition of air. The population of the Earth and the rate of its growth are the predetermining factors for increasing the intensity of pollution of all geospheres of the Earth, including the atmosphere, since with their increase, the volumes and rates of everything that is extracted, produced, consumed and sent to waste increase. Main air pollutants: Carbon monoxide Nitrogen oxides Sulfur dioxide Hydrocarbons Aldehydes Heavy metals (Pb, Cu, Zn, Cd, Cr) Ammonia Atmospheric dust

Impurities Carbon monoxide (CO) is a colorless, odorless gas also known as carbon monoxide. It is formed as a result of incomplete combustion of fossil fuels (coal, gas, oil) in conditions of lack of oxygen and at low temperatures. At the same time, 65% of all emissions come from transport, 21% from small consumers and the household sector, and 14% from industry. When inhaled, carbon monoxide, due to the double bond present in its molecule, forms strong complex compounds with human blood hemoglobin and thereby blocks the flow of oxygen into the blood. Carbon dioxide (CO2) - or carbon dioxide, is a colorless gas with a sour smell and taste, a product of the complete oxidation of carbon. It is one of the greenhouse gases.

Impurities The greatest air pollution is observed in cities where ordinary pollutants are dust, sulfur dioxide, carbon monoxide, nitrogen dioxide, hydrogen sulfide, etc. In some cities, due to the peculiarities of industrial production, the air contains specific harmful substances, such as sulfuric and hydrochloric acid, styrene, benzapyrene, carbon black, manganese, chromium, lead, methyl methacrylate. In total, there are several hundred different air pollutants in cities.

Impurities Sulfur dioxide (SO2) (sulfur dioxide, sulfur dioxide) is a colorless gas with a pungent odor. It is formed during the combustion of sulfur-containing fossil fuels, mainly coal, as well as during the processing of sulfur ores. It is primarily involved in the formation of acid rain. The global SO2 emission is estimated at 190 million tons per year. Prolonged exposure to sulfur dioxide on a person first leads to a loss of taste, shortness of breath, and then to inflammation or edema of the lungs, interruptions in cardiac activity, impaired blood circulation and respiratory arrest. Nitrogen oxides (nitrogen oxide and nitrogen dioxide) are gaseous substances: nitrogen monoxide NO and nitrogen dioxide NO2 are combined by one general formula NOx. In all combustion processes, nitrogen oxides are formed, mostly in the form of an oxide. The higher the combustion temperature, the more intense the formation of nitrogen oxides. Another source of nitrogen oxides are enterprises producing nitrogen fertilizers, nitric acid and nitrates, aniline dyes, and nitro compounds. The amount of nitrogen oxides entering the atmosphere is 65 million tons per year. Of the total amount of nitrogen oxides emitted into the atmosphere, transport accounts for 55%, energy - 28%, industrial enterprises - 14%, small consumers and the household sector - 3%.

Impurities Ozone (O3) is a gas with a characteristic odor, a stronger oxidizing agent than oxygen. It is considered one of the most toxic of all common air pollutants. In the lower atmospheric layer, ozone is formed as a result of photochemical processes involving nitrogen dioxide and volatile organic compounds. Hydrocarbons are chemical compounds of carbon and hydrogen. These include thousands of different air pollutants found in unburned gasoline, dry cleaning fluids, industrial solvents, and more. Lead (Pb) is a silvery gray metal that is toxic in any known form. Widely used for paint, ammunition, printing alloy, etc. about 60% of the world's lead production is consumed annually for the production of acid batteries. However, the main source (about 80%) of air pollution with lead compounds is the exhaust gases of vehicles that use leaded gasoline. Industrial dusts, depending on the mechanism of their formation, are divided into the following 4 classes: mechanical dust - is formed as a result of grinding the product during the technological process; sublimates - are formed as a result of volumetric condensation of vapors of substances during cooling of a gas passed through a process apparatus, installation or unit; fly ash - the non-combustible fuel residue contained in the flue gas in suspension, is formed from its mineral impurities during combustion; Industrial soot is a solid highly dispersed carbon, which is part of an industrial emission, and is formed during incomplete combustion or thermal decomposition of hydrocarbons. The main sources of anthropogenic aerosol air pollution are thermal power plants (TPP) that consume coal. Combustion of coal, production of cement and smelting of pig iron give a total emission of dust into the atmosphere equal to 170 million tons per year.

Atmospheric pollution Impurities enter the atmosphere in the form of gases, vapors, liquid and solid particles. Gases and vapors form mixtures with air, and liquid and solid particles form aerosols (dispersed systems), which are divided into dust (particle sizes over 1 µm), smoke (particle sizes less than 1 µm) and fog (liquid particle sizes less than 10 µm). ). Dust, in turn, can be coarse (particle size over 50 µm), medium-dispersed (50-10 µm) and fine (less than 10 µm). Depending on the size, liquid particles are divided into superfine mist (up to 0.5 µm), fine mist (0.5-3.0 µm), coarse mist (3-10 µm) and spray (over 10 µm). Aerosols are often polydisperse; contain particles of various sizes. The second source of radioactive impurities is the nuclear industry. Impurities enter the environment during the extraction and enrichment of fossil raw materials, their use in reactors, and the processing of nuclear fuel in installations. Permanent sources of aerosol pollution include industrial dumps - artificial mounds of redeposited material, mainly overburden, formed during mining or from waste from processing industries, thermal power plants. The production of cement and other building materials is also a source of air pollution with dust. The combustion of hard coal, the production of cement, and the smelting of pig iron give a total emission of dust into the atmosphere equal to 170 million tons/year. A significant part of aerosols is formed in the atmosphere when solid and liquid particles interact with each other or with water vapor. Among the dangerous anthropogenic factors that contribute to a serious deterioration in the quality of the atmosphere, one should include its pollution with radioactive dust. The residence time of small particles in the lower layer of the troposphere is on average several days, and in the upper one day. As for the particles that have entered the stratosphere, they can stay in it for up to a year, and sometimes more.

Atmospheric pollution The main sources of anthropogenic aerosol air pollution are thermal power plants (TPP) consuming high-ash coal, processing plants, metallurgical, cement, magnesite and other plants. Aerosol particles from these sources are characterized by great chemical diversity. Most often, compounds of silicon, calcium and carbon are found in their composition, less often - oxides of metals: iron, magnesium, manganese, zinc, copper, nickel, lead, antimony, bismuth, selenium, arsenic, beryllium, cadmium, chromium, cobalt, molybdenum, and asbestos. An even greater variety is characteristic of organic dust, including aliphatic and aromatic hydrocarbons, acid salts. It is formed during the combustion of residual petroleum products, during the pyrolysis process at oil refineries, petrochemical and other similar enterprises.

IMPACT OF ATMOSPHERIC POLLUTION ON HUMANS All air pollutants have a negative impact on human health to a greater or lesser extent. These substances enter the human body mainly through the respiratory system. The respiratory organs are directly affected by pollution, since about 50% of impurity particles with a radius of 0. µm that penetrate into the lungs are deposited in them. Statistical analysis made it possible to fairly reliably establish the relationship between the level of air pollution and diseases such as upper respiratory tract damage, heart failure, bronchitis, asthma, pneumonia, emphysema, and eye diseases. A sharp increase in the concentration of impurities, which persists for several days, increases the mortality of the elderly from respiratory and cardiovascular diseases. In December 1930, in the valley of the river Meuse (Belgium), severe air pollution was noted for 3 days; as a result, hundreds of people fell ill and 60 people died - more than 10 times the average death rate. In January 1931, in the area of ​​Manchester (Great Britain), for 9 days, there was a strong smoke in the air, which caused the death of 592 people. Cases of severe pollution of the atmosphere of London, accompanied by numerous deaths, were widely known. In 1873 there were 268 unforeseen deaths in London. Heavy smoke combined with fog between 5 and 8 December 1852 resulted in the deaths of over 4,000 residents of Greater London. In January 1956, about 1,000 Londoners died as a result of prolonged smoke. Most of those who died unexpectedly suffered from bronchitis, emphysema, or cardiovascular disease.

EFFECT OF ATMOSPHERIC POLLUTION ON HUMANS Nitrogen oxides and some other substances Nitrogen oxides (primarily poisonous nitrogen dioxide NO2), which combine with ultraviolet solar radiation with hydrocarbons (oleophins are the most reactive), form peroxylacetyl nitrate (PAN) and other photochemical oxidants, including peroxybenzoyl nitrate (PBN), ozone (O3), hydrogen peroxide (H2O2), nitrogen dioxide. These oxidizing agents are the main components of photochemical smog, the frequency of which is high in heavily polluted cities located in low latitudes of the northern and southern hemispheres (Los Angeles, where smog is observed about 200 days a year, Chicago, New York and other US cities; a number of cities Japan, Turkey, France, Spain, Italy, Africa and South America).

IMPACT OF ATMOSPHERIC POLLUTION ON HUMANS Let us name some other air pollutants that have a harmful effect on humans. It has been established that people who professionally deal with asbestos have an increased likelihood of cancer of the bronchi and diaphragms that separate the chest and abdominal cavity. Beryllium has a harmful effect (up to the oncological diseases) on the respiratory tract, as well as on the skin and eyes. Mercury vapor causes disruption of the central upper system and kidneys. Because mercury can accumulate in the human body, exposure to mercury eventually leads to mental impairment. In cities, due to ever-increasing air pollution, the number of patients suffering from diseases such as chronic bronchitis, emphysema, various allergic diseases and lung cancer is steadily increasing. In the UK, 10% of deaths are due to chronic bronchitis, with 21; of the population aged years suffers from this disease. In Japan, in a number of cities, up to 60% of the inhabitants suffer from chronic bronchitis, the symptoms of which are a dry cough with frequent expectoration, subsequent progressive difficulty in breathing and heart failure (in this regard, it should be noted that the so-called Japanese economic miracle of the 50s and 60s years was accompanied by severe pollution of the natural environment of one of the most beautiful regions of the globe and serious damage to the health of the population of this country). In recent decades, the number of bronchial and lung cancers, which are promoted by carcinogenic hydrocarbons, has been growing at a rate of great concern. Influence of radioactive substances on the flora and fauna Spreading along the food chain (from plants to animals), radioactive substances with food enter the human body and can accumulate in such quantities that can harm human health.

EFFECT OF ATMOSPHERIC POLLUTION ON HUMANS Radiation of radioactive substances has the following effects on the body: weaken the irradiated body, slow down growth, reduce resistance to infections and the body's immunity; reduce life expectancy, reduce natural growth rates due to temporary or complete sterilization; affect genes in various ways, the consequences of which appear in the second or third generations; have a cumulative (cumulative) effect, causing irreversible effects. The severity of the consequences of irradiation depends on the amount of energy (radiation) absorbed by the body and emitted by the radioactive substance. The unit of this energy is 1 row - this is the dose of radiation at which 1 g of living matter absorbs 10-5 J of energy. It has been established that at a dose exceeding 1000 rad, a person dies; at a dose of 7000 and 200 glad death occurs in 90 and 10% of cases, respectively; in the case of a dose of 100 rad, a person survives, but the likelihood of cancer is significantly increased, as well as the likelihood of complete sterilization.

IMPACT OF ATMOSPHERIC POLLUTION ON HUMANS It is not surprising that people have adapted well to the natural radioactivity of the environment. Moreover, groups of people are known living in areas with high radioactivity, much higher than the average for the globe (for example, in one of the regions of Brazil, residents receive about 1600 mrad per year, which is times more than the usual radiation dose). On average, the dose of ionizing radiation received per year by each inhabitant of the planet ranges between 50 and 200 mrad, and the share of natural radioactivity (cosmic rays) accounts for about 25 billion radioactivity of rocks - approximately mrad. The doses that a person receives from artificial sources of radiation should also be taken into account. In the UK, for example, a person receives about 100 mrad each year during fluoroscopic examinations. TV radiation - about 10 mrad. Nuclear industry waste and radioactive fallout - about 3 mrad.

Conclusion At the end of the 20th century, world civilization entered a stage of its development when the problems of survival and self-preservation of mankind, the preservation of the natural environment and the rational use of natural resources came to the fore. The current stage of human development has exposed the problems caused by the growth of the Earth's population, the contradictions between traditional management and the increasing rate of use of natural resources, pollution of the biosphere by industrial waste and the limited capacity of the biosphere to neutralize them. These contradictions hinder the further scientific and technological progress of mankind, become a threat to its existence. Only in the second half of the 20th century, thanks to the development of ecology and the spread of ecological knowledge among the population, it became obvious that humanity is an indispensable part of the biosphere, that the conquest of nature, the uncontrolled use of its resources and environmental pollution is a dead end in the development of civilization and in the evolution of man himself. Therefore, the most important condition for the development of mankind is a careful attitude to nature, comprehensive care for the rational use and restoration of its resources, and the preservation of a favorable environment. However, many do not understand the close relationship between human economic activity and the state of the natural environment. Broad environmental education should help people to acquire such environmental knowledge and ethical norms and values, attitudes and lifestyles that are necessary for the sustainable development of nature and society.

In many cities of the world there is such an environmental problem as industrial pollution. Sources of pollution are plants, factories, electric and hydroelectric power stations, boiler houses and transformer substations, gas filling and gas distribution stations, warehouses for storage and processing of products.

Types of industrial pollution

All industrial facilities carry out pollution in various ways and substances. The most common types of pollution are:

• Chemical. Dangerous for the environment, human and animal life. Pollutants are such chemicals and compounds as formaldehydes and chlorine, sulfur dioxide and phenols, hydrogen sulfide and carbon monoxide
• Pollution of the hydrosphere and lithosphere. Enterprises discharge wastewater, oil and fuel oil spills, garbage, toxic and poisonous liquids occur
• Biological. Viruses and infections enter the biosphere, which spread in the air, water, soil, cause diseases in humans and other living organisms. The most dangerous are the causative agents of gas gangrene, tetanus, dysentery, cholera, fungal diseases.
• Noise. Noises and vibrations lead to diseases of the hearing apparatus and nervous system
• Thermal. Warm water flows change the regime and temperature of the environment in the water areas, some plankton species die off, and others occupy their niche
• Radiation. Particularly dangerous pollution that occurs as a result of accidents at nuclear power plants, during the release of radioactive waste and during the production of nuclear weapons
• . Occurs due to the operation of power lines, radars, television stations, and other objects that form radio fields

Methods for reducing industrial pollution

First of all, the reduction of industrial pollution depends on the enterprises themselves. In order for this to happen, the management of factories, stations and other facilities must themselves control the work process, pay special attention to the cleaning and disposal of waste. In addition, it is necessary to use low-waste technologies and environmental developments that will reduce the level of pollution and minimize the impact on the natural environment. Secondly, the reduction of pollution depends on the competence, care and professionalism of the workers themselves. If they do an excellent job at the enterprise, this will reduce the risk of industrial pollution of cities.

Industrial enterprises as sources of environmental pollution

The industrial wastes of enterprises of the metallurgical, chemical, petrochemical, machine-building and other industries pollute the environment, which emit into the atmosphere a huge amount of ash, sulfur dioxide and other harmful gases emitted during various technological production processes. These enterprises pollute reservoirs and groundwater, affect flora and fauna. What characterizes these industries in terms of environmental protection? Ferrous and non-ferrous metallurgy are the most polluting industries and rank first in terms of emissions of toxic substances. The share of metallurgy accounts for about 40% of the total Russian gross emissions of harmful substances, including about 26% for solids and about 34% for gaseous substances. Ferrous metallurgy enterprises are the main environmental pollutants in the cities and regions in which they are located. Dust emission per 1 ton of cast iron produced is 4.5 kg, sulfur dioxide - 2.7 kg and manganese - 0.6 ... 0.1 kg. Together with blast-furnace gas, compounds of arsenic, phosphorus, antimony, lead, as well as mercury vapor, hydrogen cyanide and tarry substances are emitted into the atmosphere. Permissible sulfur dioxide emission rate during ore agglomeration is 190 kg per 1 ton of ore. At the enterprises of the industry, there continues to be a large volume of discharges of polluted wastewater into water bodies, which contain chemicals: sulfates, chlorides, iron compounds, heavy metals. These discharges are so large that they turn rivers and reservoirs in their places into "extremely dirty". Ferrous metallurgy enterprises discharge 12% of polluted wastewater, which is more than a quarter of all toxic waste of Russian industry. The volume of polluted water discharges increased by 8% compared to previous years. Novolipetsk, Magnitogorsk, Zlatoust, Satka metallurgical plants became the largest industry sources of water pollution. Ferrous metallurgy enterprises affect the state of groundwater through filter tanks. Thus, the Novolipetsk Iron and Steel Works has become a source of groundwater pollution with rhodonides (up to 957 MPC), cyanides (up to 308 MPC), oil products and phenols. It should also be noted that this industry is a source of soil pollution. According to aerospace survey data, the soil cover contamination zone can be traced at a distance of up to 60 km from the pollution source. The main reasons for significant emissions and discharges of pollutants, as experts explain, is the incomplete equipment of enterprises with treatment plants or their inoperative state (for various reasons). Only half of the wastewater is treated to the norm, and the neutralization of gaseous substances is only about 60% of the total emission. At the enterprises of non-ferrous metallurgy, despite the decline in production, the reduction of harmful environmental pollutants did not occur. As noted above, non-ferrous metallurgy continues to be the leader in environmental pollution in Russia. Suffice it to mention only the Norilsk Nickel Concern, the main supplier of non-ferrous and precious metals, which, along with metal production, supplies about 12% of the gross pollutant emissions of the entire Russian industry into the atmosphere. In addition, there are enterprises "Yuzhuralnickel" (Orsk); Sredneuralsky copper smelter (Revda); Achinsk Alumina Refinery (Achinsk); Krasnoyarsk aluminum plant; Mednogorsk copper-sulfur plant. Atmospheric pollution by these enterprises is mainly characterized by emissions of SO2 (more than 80% of the total emissions into the atmosphere), CO (10.5%) and dust (10.45%). Emissions to the atmosphere influence the formation of chemical fluxes over long distances. At non-ferrous metallurgy enterprises, there are large volumes of wastewater that are contaminated with mineral substances, fluorine reagents containing cyanides, petroleum products, xanthates, salts of heavy metals (copper, lead, zinc, nickel), as well as arsenic, fluorine, antimony, sulfates, chlorides, etc. Heavy metals were found in the soil cover where the enterprises are located, exceeding the MPC by 2 ... 5 times or more. For example, around Rudnaya Pristan (Primorsky Territory), where a lead plant is located, soils with a radius of 5 km are contaminated with lead - 300 MPC and manganese - 2 MPC. There is no need to give examples of other cities. And now let's raise the question, what is the zone of pollution of the air basin and the earth's surface from the center of pollutant emissions. Here is an impressive example of research carried out by the Russian Ecological Fund on the degree of impact of pollution by non-ferrous metallurgy enterprises on ecosystems. On fig. 2.3 shows the zones of destroyed ecosystems from the center of harmful emissions. As can be seen from the figure, the configuration of the pollution field is close to circular; it can be in the form of an ellipse and other geometric shapes, depending on the wind rose. According to the integral coefficient of conservation (IC,%) obtained (experimentally), the following zones of ecosystem disturbance were established: - complete destruction of ecosystems (technogenic wasteland); - severe destruction of the ecosystem. The average life expectancy of needles (coniferous forest) is 1...3 years instead of 11...13 years. There is no regeneration of coniferous forest; - partial disturbance of ecosystems. Precipitation of sulfate ion during the day is 3...7 kg/km2, non-ferrous metals - tens of grams per 1 km2. The resumption of life in the coniferous forest is very weak; - the initial stage of destruction of ecosystems. The maximum concentrations of S02 are 0.4...0.5 kg/km2. Non-ferrous metal concentrations exceed background values; - the initial stage of degradation of ecosystems. There are almost no visible signs of damage to vegetation, however, in the needles of spruces, a background state of heavy metals is observed, which exceeds the norm by 5...10 times.
Rice. 2.3. Preservation of Ecosystems Depending on the Distance to the Center of Harmful Emissions Studies show that as a result of the uncontrolled activities of a metallurgical plant, the natural environment has been practically destroyed over large areas. Forests were destroyed and damaged on an area of ​​about 15 thousand hectares, and signs of the initial stage of destruction of forest ecosystems were recorded on 400 thousand hectares. The analysis of the pollution of this territory made it possible to establish the rate of destruction of the ecosystem, which amounted to 1 ... 1.5 km / year. What will happen next with such indicators? All wildlife at a distance of up to 30 km from the plant (according to the wind rose) can completely degrade within 20...25 years. Heavy metals have a harmful effect not only on water bodies, but also on ordinary mushrooms, berries and other plants, the toxicity of which reaches 25 MPC, and they become completely unsuitable for human consumption. Pollution of water bodies located near the plant is more than 100 MPC. In residential areas of the city, the concentration of SO2, nitrogen oxides and heavy metals exceeds the maximum permissible level by 2... 4 times. Hence the morbidity of the population with diseases of the endocrine system, blood, sensory organs and skin. This fact is also curious. In the vicinity of the plant, the first colony of moles was found at a distance of 16 km from the center of emissions, voles were captured no closer than 7...8 km. Moreover, at these distances, animals do not live permanently, but only temporarily enter. This means that with an increase in anthropogenic load, biogeocenosis, as it were, is simplified primarily due to the loss or sharp reduction of consumers. Thus, the cycle of carbon (and other elements) becomes two-term: producers - reducers. At the enterprises of the chemical and petrochemical industries, the very nature of the raw materials speaks of their negative impact on the environment, since we are talking about the production of plastics, synthetic dyes, synthetic rubber, carbon black. According to the report, in 2000 alone, these industries emitted more than 427,000 tons of polluted substances into the atmosphere, while the volume of toxic waste increased and amounted to more than 13 million tons. This is 11% of the volume of toxic waste generated per year in Russian industry. Chemical and petrochemical industries emit a variety of toxic substances (CO, SO2, solids, nitrogen oxides), most of which are dangerous to the human body. This affects the hydrochemical state of water bodies. So, for example, the waters of the Belaya River (upstream from the city of Sterlitamak, Bashkiria) belong to the III class of harmfulness (or simply dirty). Almost the same thing happens with the waters of the Oka River after discharges from the factories of Dzerzhinsk (Nizhny Novgorod region), which contain elements of methanol, cyanide, and formaldehyde. There are many such examples. They pollute not only surface waters, but also underground ones, which makes it impossible to use aquifers for drinking water supply. Pollution of groundwater with heavy metals, methanol, phenol exceeds the MPC up to hundreds of thousands of times. Around the enterprises of the chemical industry (more precisely, cities), the soil is also polluted, as a rule, within a radius of up to 5 ... 6 km. About 80% of 2.9 km3 of wastewater is polluted, which indicates an extremely inefficient operation of treatment facilities. The composition of wastewater includes sulfates, chlorides, phosphorus and nitrogen compounds, petroleum products, as well as specific substances such as formaldehyde, methanol, benzene, hydrogen sulfide, carbon disulfide, heavy metal compounds, mercury, arsenic, etc. The building materials industry covers a wide range of enterprises not only cement plants, but also plants for the production of reinforced concrete products, various ceramic and polymer products, plants for the production of asphalt-bitumen mixture, concrete and mortar. The technological processes of these industries are mainly associated with the grinding and heat treatment of charge (at cement plants), the unloading of cement and the preparation of semi-finished products. In the process of obtaining products and materials, dust and various gases enter the atmospheric air, and untreated sewage enters the sewer networks. Asphalt-mixing plants of various capacities currently operating in Russia emit from 70 to 300 tons of suspended chemicals per year into the atmosphere. Installations emit carcinogens into the air. Purification equipment, according to the report on environmental protection, does not work on any of them or does not meet the technical condition.

Air pollution is an environmental problem. This phrase does not reflect in the slightest degree the consequences that a violation of the natural composition and balance in a mixture of gases called air bears.

It is not difficult to illustrate such a statement. The World Health Organization provided data on this topic for 2014. About 3.7 million people have died due to air pollution worldwide. Almost 7 million people died from exposure to polluted air. And this is in one year.

The composition of the air includes 98-99% nitrogen and oxygen, the rest: argon, carbon dioxide, water and hydrogen. It makes up the Earth's atmosphere. The main component, as we see, is oxygen. It is necessary for the existence of all living things. Cells “breathe” it, that is, when it enters the cell of the body, a chemical oxidation reaction occurs, as a result of which the energy necessary for growth, development, reproduction, exchange with other organisms, and the like, that is, for life, is released.

Atmospheric pollution is interpreted as the introduction of chemical, biological and physical substances that are not inherent in it into the atmospheric air, that is, a change in their natural concentration. But more important is not the change in concentration, which, no doubt, occurs, but the decrease in the composition of the air of the most useful component for life - oxygen. After all, the volume of the mixture does not increase. Harmful and polluting substances are not added by simple addition of volumes, but destroy and take its place. In fact, there is and continues to accumulate a lack of food for the cells, that is, the basic nutrition of a living being.

About 24,000 people per day die of starvation, that is, about 8 million per year, which is comparable to the death rate from air pollution.

Types and sources of pollution

The air has been polluted at all times. Volcanic eruptions, forest and peat fires, dust and pollen from plants and other substances entering the atmosphere that are usually not inherent in its natural composition, but that occurred as a result of natural causes - this is the first type of air pollution origin - natural. The second is as a result of human activity, that is, artificial or anthropogenic.

Anthropogenic pollution, in turn, can be divided into subspecies: transport or resulting from the operation of different modes of transport, industrial, that is, associated with emissions into the atmosphere of substances formed in the production process and domestic or resulting from direct human activity.

Air pollution itself can be physical, chemical and biological.

• The physical includes dust and solid particles, radioactive radiation and isotopes, electromagnetic waves and radio waves, noise, including loud sounds and low-frequency vibrations, and thermal, in any form.
• Chemical pollution is the ingress of gaseous substances into the air: carbon monoxide and nitrogen, sulfur dioxide, hydrocarbons, aldehydes, heavy metals, ammonia and aerosols.
• Microbial contamination is called biological. These are various spores of bacteria, viruses, fungi, toxins and the like.

The first is mechanical dust. Appears in the technological processes of grinding substances and materials.

The second is sublimations. They are formed during the condensation of cooled gas vapors and passed through the process equipment.

The third is fly ash. It is contained in the flue gas in a suspended state and is an unburned mineral fuel impurities.

The fourth is industrial soot or solid highly dispersed carbon. It is formed during the incomplete combustion of hydrocarbons or their thermal decomposition.

Today, the main sources of such pollution are thermal power plants operating on solid fuels and coal.

Consequences of pollution

The main consequences of air pollution are: the greenhouse effect, ozone holes, acid rain and smog.

The greenhouse effect is built on the ability of the Earth's atmosphere to transmit short waves and delay long ones. Short waves are solar radiation, and long waves are thermal radiation coming from the Earth. That is, a layer is formed in which heat is accumulated or a greenhouse. Gases capable of such an effect are called, respectively, greenhouse gases. These gases heat up themselves and heat up the entire atmosphere. This process is natural and natural. It happened and is happening now. Without it, life on the planet would not be possible. Its beginning is not connected with human activity. But if earlier nature itself regulated this process, now man has intensively intervened in it.

Carbon dioxide is the main greenhouse gas. Its share in the greenhouse effect is more than 60%. The share of the rest - chlorofluorocarbons, methane, nitrogen oxides, ozone, and so on, accounts for no more than 40%. It was thanks to such a large proportion of carbon dioxide that natural self-regulation was possible. How much carbon dioxide was released during breathing by living organisms, so much was consumed by plants, producing oxygen. Its volumes and concentration were kept in the atmosphere. Industrial and other human activities, and, above all, deforestation and burning of natural fuels, have led to an increase in carbon dioxide and other greenhouse gases due to a decrease in the volume and concentration of oxygen. The result was a greater heating of the atmosphere - an increase in air temperature. Forecasts are such that rising temperatures will lead to excessive melting of ice and glaciers and rising sea levels. This is on the one hand, and on the other hand, due to higher temperatures, the evaporation of water from the surface of the earth will increase. And that means an increase in desert lands.

Ozone holes or disruption of the ozone layer. Ozone is a form of oxygen and is formed naturally in the atmosphere. This happens when ultraviolet radiation from the sun hits an oxygen molecule. Therefore, the highest concentration of ozone in the upper atmosphere is at an altitude of about 22 km. from the surface of the earth. In height, it extends for about 5 km. this layer is considered protective, as it delays this very radiation. Without such protection, all life on Earth perished. Now there is a decrease in the concentration of ozone in the protective layer. Why this happens has not yet been reliably established. This depletion was first detected in 1985 over Antarctica. Since then, the phenomenon has been called the "ozone hole". At the same time, the Convention for the Protection of the Ozone Layer was signed in Vienna.

Industrial emissions of sulfur dioxide and nitrogen oxide into the atmosphere, combined with atmospheric moisture, form sulfuric and nitric acid and cause "acid" rain. Such precipitation is considered to be any precipitation whose acidity is higher than natural, that is, ph<5,6. Это явление присуще всем промышленным регионам в мире. Главное их отрицательное воздействие приходится на листья растений. Кислотность нарушает их восковой защитный слой, и они становятся уязвимы для вредителей, болезней, засух и загрязнений.

Falling onto the soil, the acids contained in their water react with toxic metals in the ground. Such as: lead, cadmium, aluminum and others. They dissolve and thereby contribute to their penetration into living organisms and groundwater.

In addition, acid rain contributes to corrosion and thus affects the strength of buildings, structures and other building structures made of metal.

Smog is a common sight in large industrial cities. It occurs where a large amount of pollutants of anthropogenic origin and substances obtained as a result of their interaction with solar energy accumulate in the lower layers of the troposphere. Smog is formed and lives for a long time in cities, thanks to calm weather. Exists: wet, icy and photochemical smog.

With the first explosions of nuclear bombs in the Japanese cities of Hiroshima and Nagasaki in 1945, mankind discovered another, perhaps the most dangerous, type of air pollution - radioactive.

Nature has the ability to self-cleanse, but human activity clearly interferes with this.

Video - Unsolved Mysteries: How Air Pollution Affects Health

Distinguish natural(natural) and anthropogenic(artificial) sources of pollution. To natural sources include: dust storms, fires, various aerosols of plant, animal or microbiological origin, etc. Anthropogenic emissions into the atmosphere annually amount to more than 19 billion tons, of which more than 15 billion tons of carbon dioxide, 200 million tons of carbon monoxide, more than 500 million tons of hydrocarbons, 120 million tons of ash, etc.

On the territory of the Russian Federation, for example, in 1991, emissions of pollutants into the air amounted to about 53 million tons, including industry - 32 million tons (61%), motor transport - 21 million tons (39%). In one of the largest regions of the country, the Rostov region, emissions of pollutants into the atmospheric air in 1991 and 1996 amounted to 944.6 thousand tons and 858.2 thousand tons, respectively, including:

solids	112.6 thousand tons
sulfur dioxide	184.1 thousand tons	133.0 thousand tons
carbon monoxide	464.0 thousand tons	467.1 thousand tons
nitrogen oxide
hydrocarbons
flying org. conn.

More than half of the total is emissions from vehicles. Pollution is mainly obtained as by-products or wastes from the extraction, processing and use of resources, and can also be a form of harmful energy emissions, such as excess heat, noise and radiation.

Most natural pollutants (eg volcanic eruption, coal burning) are dispersed over a wide area, and their concentration is often reduced to a safe level (due to decomposition, dissolution and dispersion). Anthropogenic air pollution occurs in urban areas, where large amounts of pollutants are concentrated in small volumes of air.

The following eight categories of pollutants are considered the most dangerous and widespread:

1) suspensions - the smallest particles of a substance in suspension;

2) hydrocarbons and other volatile organic compounds in the air in the form of vapors;

3) carbon monoxide (CO) - extremely toxic;

4) nitrogen oxides (NO x) - gaseous compounds of nitrogen and oxygen;

5) sulfur oxides (SO 2 dioxide) - a poisonous gas that is dangerous for plants and animals;

6) heavy metals (copper, tin, mercury, zinc, etc.);

7) ozone and other photochemical oxidizers;

8) acids (mainly sulfuric and nitric).

Consider what these pollutants are and how they are formed.

In large cities, two main types of pollutant sources can be found: pinpoint such as CHP chimney, chimney, car exhaust, etc. and non-point- entering the atmosphere from extensive sources.

There are solid, liquid and gaseous substances that pollute the environment.

Solid- are formed during the mechanical processing of materials or their transportation, during combustion and thermal production processes. These include dust and suspensions formed: the first - during the extraction, processing and transportation of bulk materials, various technological processes and wind erosion; the second - in the open burning of waste and from industrial pipes as a result of a variety of technological processes.

Liquid pollutants are the product of chemical reactions, condensation or liquid spraying in technological processes. The main liquid pollutants are oil and products of its processing, polluting the atmosphere with hydrocarbons.

gaseous pollutants are formed as a result of chemical reactions, electrochemical processes, fuel combustion, reduction reactions. The most common pollutants in the gaseous state are: carbon monoxide CO, carbon dioxide CO 2, nitrogen oxides NO, N 2 O, NO 2, NO 3, N 2 O 5, sulfur dioxide SO 2, chlorine and fluorine compounds.

Consider the most dangerous, widespread pollutants. What are they and what is their danger?

1. Dust and suspension- these are fine particles suspended in the air, for example, smoke and soot (Table 4.2). The main sources of particulate matter are industrial pipes, transport and open burning of fuel. We can observe such suspensions in the form of smog or haze.

By dispersion, i.e. degrees of grinding distinguish dust:

Coarse - with particles larger than 10 microns, settling in still air with increasing speed;

Medium-dispersed - with particles from 10 to 5 microns, slowly settling in still air;

Fine and smoke - with particles 5 microns in size, quickly dissipating in the environment and almost not settling.

Table 4.2

Main sources of air pollution

	Aerosols	Gaseous emissions
Boilers and industrial furnaces		NO 2, SO 2, as well as CO, aldehydes (HCHO), organic acids, benzapyrene
Automotive engines		CO, NO 2 , aldehydes, non-carcinogenic hydrocarbons, benzapyrene
Oil refining industry		SO 2 , H 2 S, NH 3 , NO x , CO, hydrocarbons, acids, aldehydes, carcinogens
Chemical industry		Depending on the process (H 2 S, CO, NH 3), acids, organics, solvents, volatile sulfides, etc.
Metallurgy and coke chemistry		SO 2 , CO, NH 3 , NO X , fluorine and cyanide compounds, organic substances, benzapyrene
Mining		Depending on the process (CO, fluorides, organics)
food industry		NH 3 , H 2 S, mixtures of organic compounds
Building materials industry		CO, organic compounds

Dust that can remain suspended in the air for some time is called spray can, in contrast to settled dust, called airgel. Fine dust poses the greatest danger to the body, since it does not linger in the upper respiratory tract and can penetrate deep into the lungs. In addition, fine dust can be a conductor of various toxic substances into the human body, for example, heavy metals, which, on dust particles, can penetrate deep into the respiratory tract.

Other examples can be given: the combination of sulfur dioxide with dust irritates the skin and mucous membranes, with an increase in concentration it leads to respiratory problems and chest pains, and at very high concentrations, far exceeding the MPC, causes death from suffocation.

In machine-building enterprises, especially in the shops of hot and cold metal processing, a lot of dust, toxic and irritating gases are released into the air of working areas. The modern standard sets the MPC for harmful substances of about 1000 types. According to the degree of impact on the body, harmful substances are divided into four classes:

1st - substances are extremely dangerous;

2nd - highly dangerous substances;

3rd - moderately hazardous substances;

4th - substances of low danger.

The hazard class of substances is established depending on the norms and indicators (Table 4.3).

Table 4.3

Hazard classes and pollution levels

The maximum permissible concentrations of harmful substances in the air of the working area are concentrations that, during daily 8-hour (except weekends) work or for other durations (but not more than 41 hours per week) during the entire working experience, do not cause diseases or deviations in the state health.

The maximum allowable concentration represents the primary standard, which is a criterion for pollution, this is the maximum level of pollution that a person can tolerate without harm to health, plus 10-15% as a margin of safety.

2. hydrocarbons are organic compounds of carbon and hydrogen. In engineering and industry, they are used as energy carriers, for example, natural gas, propane, gasoline, solvents for paints and cleaning products, etc. Among the most dangerous hydrocarbons, benzapyrene occupies an important place - a component of vehicle exhaust gases and atmospheric emissions from coal stoves.

3. Carbon monoxide. With the complete combustion of fuel and waste, which are organic compounds, carbon dioxide and water are formed:

CH 4 + 2O 2 \u003d CO 2 + 2H 2 O.

In the case of complete combustion, carbon dioxide is released into the air, also called carbon dioxide (CO 2) with incompletely oxidized carbon - carbon monoxide (CO).

Carbon dioxide, a colorless gas with a slight odor, is formed during the respiration of living organisms, as well as during the combustion of coal, oil and gas at thermal stations, boiler houses, etc. In small quantities, carbon dioxide is not dangerous, but in very large doses it leads to death. The content of CO 2 in the air is constantly growing, which is associated with an ever-increasing amount of burning coal and oil. Over the past 100 years, the content of carbon dioxide in the air has increased by about 14%. An increase in carbon dioxide content in the air contributes to an increase in temperature on Earth, since a layer of carbon dioxide creates a powerful screen that does not let the heat emitted by the Earth into space, which disrupts the natural heat exchange between the planet and its surrounding space. This so-called greenhouse, or greenhouse effect.

Carbon monoxide (CO) is not completely oxidized carbon, the so-called carbon monoxide. CO is a poisonous gas that is colorless and odorless. Inhalation of carbon monoxide blocks the flow of oxygen into the blood, leads to oxygen starvation of tissues, followed by fainting, paralysis of the respiratory tract and death.

4. nitrogen oxides(NO x) - gaseous compounds of substances produced by microorganisms; can also be formed in the products of fuel combustion in automobile engines, in the chemical industry, for example, in the production of nitric acid. At high combustion temperatures, part of the nitrogen (N 2) is oxidized, forming monoxide (NO), which in the air, reacting with oxygen, is oxidized to dioxide (NO 2) and / or tetroxide (N 2 O 4).

Nitrogen oxides contribute to the emergence of photochemical smog formed from the products of the reaction between nitrogen oxides and unsaturated hydrocarbons under the active influence of ultraviolet radiation from the Sun.

Nitrogen oxides irritate the respiratory organs, mucous membranes, especially the lungs and eyes, and also have a negative effect on the human brain and nervous system.

5. Sulfur dioxide or the so-called sulfur dioxide (SO 2 ) - a sharp-smelling, colorless gas that irritates the respiratory tract of humans and animals, especially in fine dust environments. The main sources of air pollution with sulfur dioxide are fossil fuels burned in power plants. Fuel and waste that enter the air during combustion contain sulfur (for example, in coal from 0.2 to 5.5% sulfur). During combustion, sulfur is oxidized to form SO 2 . Sulfur dioxide causes serious damage to the environment - under the action of SO 2, plants partially die off chlorophyll, which adversely affects agricultural crops, forest trees, water bodies, falling out in the form of so-called acid rain.

6. Heavy metals, polluting the environment, bring great harm to man and nature. Lead, mercury, cadmium, copper, nickel, zinc, chromium, vanadium are permanent components of the air in large industrial centers. Heavy metal impurities can contain coal, as well as various wastes.

Examples: where tetraethyl lead is used as an additive in gasoline to cheaply prevent engine knocking (in a number of countries this method of adding is prohibited), the air is significantly polluted with lead. Released with exhaust gases, this harmful heavy metal remains in the air and, before settling, is carried by the wind over long distances.

Another heavy metal, mercury, getting from polluted air into water in the process of bioaccumulation in lakes, enters the organisms of fish, which creates a serious danger of human poisoning along the food chain.

7. Ozone and various active organic compounds, which are formed in the process of chemical interactions of nitrogen oxides with volatile hydrocarbons, stimulated by the rays of the sun. The products of these reactions are called photochemical oxidants. For example, under the influence of solar energy, nitrogen dioxide decomposes into monoxide and an oxygen atom, which, combining with O 2, forms ozone O 3.

8. acids, predominantly sulfuric and nitric, which form acid rain.

What objects of sources of atmospheric pollution constitute the main danger to the health of the planet?

The main air pollutants in industrialized countries are cars and other modes of transport, industrial enterprises, thermal power plants, large complexes of the military industry and nuclear energy.

Motor transport pollutes the air of cities with carbon and nitrogen monoxide, hydrocarbons and other harmful substances. Annual car emissions in Russia in the early 90s amounted to 36 million tons or 37% of the total emissions (about 100 million tons / year), including: nitrogen oxides - 22%, hydrocarbons - 42%, carbon oxides - about 46% (the largest volume of emissions from cars was noted in Moscow - more than 840 thousand tons / year).

Now in the world there are several hundred million only private cars, almost half of them - about 200 million - in the Americas. In Japan, due to the limited territory, there are almost 7 times more motorists per unit area than in the United States. On the conscience of the car - this "chemical factory on wheels" - more than 60% of all harmful substances in the city air. Car exhaust gases contain about 200 substances that are harmful to health and nature. They contain unburned or incompletely decomposed fuel hydrocarbons. The amount of hydrocarbons increases dramatically if the engine is running at low speeds or at increased speed, for example, when starting at intersections at traffic lights. At the moment of pressing the accelerator pedal, a large amount of unburned particles is released (10-12 times more than in normal mode). In addition, the unburned exhaust gases of the engine during normal operation contain about 2.7% carbon monoxide, the amount of which increases with a decrease in speed to about 3.9-4%, and at low speed - up to 6.9%.

Exhaust gases, including carbon monoxide, carbon dioxide and many other engine emissions, are heavier than air, so they all accumulate near the ground, poisoning people and vegetation. With the complete combustion of fuel in the engine, part of the hydrocarbons turns into soot containing various resins. Especially in the event of an engine failure, a black plume of smoke trails behind the car, containing polycyclic hydrocarbons, including benzapyrene. Exhaust gases also contain nitrogen oxides, aldehydes, which have a pungent odor and irritating effect, and inorganic lead compounds.

Ferrous metallurgy is one of the major sources of air pollution with dust and gases. In the process of smelting pig iron and processing it into steel, dust emissions per 1 ton of hot metal are 4.5 kg, sulfur dioxide - 2.7 kg and manganese - 0.5-0.1 kg.

A significant role in air pollution is played by emissions from open-hearth and converter steel-smelting shops. Emissions from open-hearth furnaces mainly contain dust from iron trioxide (76%) and aluminum trioxide (8.7%). With an oxygen-free process, 3000-4000 m 3 of gases are released per 1 ton of open-hearth steel with a dust concentration of about 0.6-0.8 g/m 3 . In the process of supplying oxygen to the zone of molten metal, the formation of dust increases significantly, reaching 15-52 g/m 3 . At the same time, hydrocarbon and sulfur burn out, and therefore the emissions of open-hearth furnaces contain up to 60 kg of carbon monoxide and up to 3 kg of sulfur dioxide per 1 ton of steel produced.

The process of obtaining steel in converter furnaces is characterized by the emission of flue gases into the atmosphere, consisting of particles of oxides of silicon, manganese and phosphorus. The composition of the smoke contains up to 80% carbon monoxide, and the concentration of dust in the exhaust gases is about 15 g/m3.

Emissions from non-ferrous metallurgy contain industrial dust-like substances: arsenic, lead, fluorine, etc., therefore they pose a serious danger to human health and the environment. In the process of aluminum production by electrolysis, a large amount of gaseous and dusty fluorine compounds are emitted into the atmosphere. To obtain 1 ton of aluminum, from 33 to 47 kg of fluorine is consumed (depending on the power of the electrolyzer), more than 65% of which enters the atmosphere.

Chemical industry enterprises are among the most dangerous sources of air pollution. The composition of their emissions is very diverse and contains many new, extremely harmful substances. Little is known about the potentially harmful effects of 80% of these substances on humans, animals and nature. The main emissions of chemical industry enterprises include carbon monoxide, nitrogen oxides, sulfur dioxide, ammonia, organic substances, hydrogen sulfide, chloride and fluorine compounds, dust from inorganic industries, etc.

The fuel and energy complex (thermal power plants, combined heat and power plants, boiler plants) emits smoke into the atmospheric air, which is formed during the combustion of solid and liquid fuels. Air emissions from fuel-burning plants contain products of complete combustion - sulfur oxides and ash, products of incomplete combustion - mainly carbon monoxide, soot and hydrocarbons. The total volume of all emissions is very significant. For example, a thermal power plant that consumes 50 thousand tons of coal containing approximately 1% sulfur every month emits 33 tons of sulfuric anhydride into the atmosphere every day, which can turn (under certain meteorological conditions) into 50 tons of sulfuric acid. In one day, such a power plant produces up to 230 tons of ash, which is partially (about 40-50 tons per day) released into the environment within a radius of up to 5 km. Emissions from thermal power plants that burn oil contain almost no ash, but emit three times more sulfuric anhydride.

Air pollution from the oil-producing, oil-refining and petrochemical industries contains a large amount of hydrocarbons, hydrogen sulfide and foul-smelling gases.

Previous