Problems of atmospheric air pollution by industrial enterprises. Air pollution is a serious environmental problem
"Air pollution - ecological 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. They "breathe" the cells, that is, when it enters the cell of the body, chemical reaction oxidation, as a result of which the energy necessary for growth, development, reproduction, exchange with other organisms and the like is released, that is, for life.
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 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 release of substances into the atmosphere that are usually not inherent in it natural composition, but 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 work different types transport, industrial, that is, associated with emissions into the atmosphere of substances formed in the production process and household 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 oscillations, 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 technological processes grinding of 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 effects of pollution atmospheric air 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 She herself regulated this process, but now a person 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 by reducing 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, increase, due to more high temperature the evaporation of water from the surface of the earth. And that means an increase in desert lands.
Ozone holes or disruption of the ozone layer. Ozone is a form of oxygen and is produced in the atmosphere. naturally. This happens when it hits ultraviolet radiation sun to an oxygen molecule. Therefore, the highest concentration of ozone in upper layers atmosphere 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-purify, but human activity clearly interferes with this.
Video - Unsolved Mysteries: How Air Pollution Affects Health
For millions of years, smoke and pollutants have been released into the atmosphere from volcanic eruptions. At the same time, the biosphere itself coped with such gigantic pollution. Even when a person learned to make fire, this fragile shell retained the quality of the air for a long time. This continued until the Industrial Revolution.
The largest cities of any country are, as a rule, large industrial centers in which tens and hundreds of industrial enterprises of various industries are concentrated. Enterprises of the chemical, metallurgical and other industries emit dust, sulfur dioxide and other harmful gases into the atmosphere, which are released during various technological processes.
Ferrous metallurgy. The processes of smelting pig iron and processing it into steel are accompanied by the emission of various gases into the atmosphere. Air pollution by dust during coal coking is associated with the preparation of the charge and its loading into coke ovens, with the unloading of coke into quenching cars and with wet quenching of coke. Wet quenching of coke is also accompanied by the release into the atmosphere of substances that are part of the water used.
Non-ferrous metallurgy. During the production of aluminum metal by electrolysis, a significant amount of gaseous and dust-like fluorine compounds is released into the atmospheric air with exhaust gases from electrolysis baths.
Air emissions from oil and petrochemical industries contain large amounts of hydrocarbons, hydrogen sulfide and foul-smelling gases. The emission of harmful substances into the atmosphere at oil refineries occurs mainly due to insufficient sealing of equipment.
The production of cement and building materials can be a source of air pollution with various dusts. The main technological processes of these industries are the processes of grinding and heat treatment of batches, semi-finished products and products in hot gas flows, which is associated with dust emissions into the atmospheric air.
The chemical industry includes a large group of enterprises. The composition of their industrial emissions is very diverse. The main emissions from the chemical industry are carbon monoxide, nitrogen oxides, sulfur dioxide, ammonia, dust from inorganic industries, organic substances, hydrogen sulfide, carbon disulfide, chloride and fluorine compounds. Of all types of chemical industries, the greatest pollution is caused by those where varnishes and paints are made or used. This is due to the fact that varnishes and paints are often made on the basis of alkyd and other polymeric materials, as well as nitro-varnishes, they usually contain a large percentage of solvent. Emissions of anthropogenic organic substances in industries associated with the use of varnishes and paints is 350 thousand tons per year, the rest of the chemical industry as a whole emit 170 thousand tons per year.
In the middle of the 20th century, large cities found themselves in conditions of intense air pollution. Natural circulation often could not cope with the purification of the atmosphere and, as a result, the incidence of acute respiratory diseases (such as asthma, emphysema) increased among the population.
Air pollution poses a threat not only to human health, but also causes great damage to natural ecosystems, such as forests. So-called acid rain, caused mainly by sulfur dioxide and nitrogen oxides, affects vast areas of the taiga forest. In Russia alone, the total area affected by industrial emissions has reached 1 million hectares. Green spaces in industrial cities are especially hard hit.
Air pollution causes great damage to the economy. Toxic substances in the air poison livestock, discolor the paint on the walls of houses and car bodies.
What is the way out? He is. It is necessary to look for such ways of developing industry and achieving purity of the atmosphere that would not exclude each other and would not cause an increase in the cost of treatment facilities. One of these ways is the transition to a fundamentally new production technology, to the integrated use of raw materials. Plants and factories based on waste-free technology are the industry of the future. The Orenburg gas field began to produce by-products - hundreds of thousands of tons of sulfur. At the Kirovkansky chemical plant named after Myasnik, the emission of mercury gases into the atmosphere has been stopped. They are re-introduced into the technological cycle as a cheap raw material for the production of ammonia and urea. Together with them, the most harmful substance - carbon dioxide, which makes up 60% of all plant emissions, no longer enters the air pool. Enterprises for the integrated use of raw materials provide society with enormous benefits: they sharply increase the efficiency of capital investments and just as sharply reduce the cost of building expensive treatment facilities. After all, the complete processing of raw materials at one enterprise is always cheaper than obtaining the same products at different ones. And waste-free technology eliminates the danger of air pollution.
Tall chimneys are a typical attribute of the picture of a modern industrial center. The chimney has two purposes: the first is to create draft and thereby force air - an obligatory participant in the combustion process - to enter the furnace in the right amount and at the right speed; the second is to remove combustion products - harmful gases and solid particles present in the smoke - into the upper layers of the atmosphere. Due to the continuous, turbulent movement, harmful gases and solid particles are carried away from their source and dispersed. Pipes 180, 250 and 320 meters high are currently being built to disperse sulfur dioxide contained in the flue gases of thermal power plants. A chimney 100 meters high disperses the smallest harmful substances in a circle with a radius of 20 km to a concentration that is harmless to humans. A 250 m high pipe increases the dispersion radius to 75 km. In the immediate surroundings of the pipe, a so-called shadow zone is created, into which harmful substances do not enter at all.
The concept of "resources of the atmosphere"
Atmospheric air as a resource. Atmospheric air is a natural mixture of gases of the surface layer of the atmosphere outside residential, industrial and other premises, which has developed during the evolution of our planet. It is one of the main vital elements of nature.
Atmospheric air performs a number of complex environmental functions, namely:
1) regulates the thermal regime of the Earth, promotes the redistribution of heat around the globe;
2) serves as an indispensable source of oxygen necessary for the existence of all life on Earth. When characterizing the special importance of air in human life, it is emphasized that a person can live without air for only a few minutes;
3) is a conductor of solar energy, serves as protection against harmful cosmic radiation, forms the basis of climatic and weather conditions on Earth;
4) is intensively exploited as a transport communication;
5) saves everything living on Earth from destructive ultraviolet, X-ray and cosmic rays;
6) protects the Earth from various celestial bodies. The vast majority of meteorites do not exceed the size of a pea. With great speed (from 11 to 64 km / s), they crash into the atmosphere of the planet under the influence of earth's gravity, heat up due to friction against the air, and at a height of about 60-70 km they mostly burn out;
7) determines the light regime of the Earth, breaks the sun's rays into millions of small rays, scatters them and creates the uniform illumination that a person is used to;
8) is the medium where sounds propagate. Without air, silence would reign on Earth;
9) has the ability to self-purify. It occurs when aerosols are washed out of the atmosphere by precipitation, turbulent mixing in the surface air layer, and the deposition of polluted substances on the earth's surface.
Atmospheric air and the atmosphere as a whole have many other environmental and socially beneficial properties. For example, atmospheric air is widely used as a natural resource in the national economy. Mineral nitrogen fertilizers, nitric acid and its salts are produced from atmospheric nitrogen. Argon and nitrogen are used in metallurgy, chemical and petrochemical industries (for a number of technological processes). Oxygen and hydrogen are also obtained from atmospheric air.
Atmospheric air pollution by industrial enterprises
Pollution in ecology is understood as an unfavorable change in the environment, which is wholly or partly the result of human activity, directly or indirectly changes the distribution of incoming energy, radiation levels, physical and chemical properties of the environment and the conditions for the existence of living organisms. These changes can affect a person directly or through water and food. They can also affect a person, worsening the properties of the things he uses, the conditions of rest and work.
Intensive air pollution began in the 19th century due to the rapid development of industry, which began to use coal as the main fuel, and the rapid growth of cities. The role of coal in air pollution in Europe has long been known. However, in the 19th century, it was the cheapest and most affordable type of fuel in Western Europe, including Great Britain.
But coal is not the only source of air pollution. Now a huge amount of harmful substances is emitted into the atmosphere every year, and, despite the significant efforts made in the world to reduce the degree of atmospheric pollution, it is located in the developed capitalist countries. At the same time, the researchers note that if there are now 10 times more harmful impurities in the atmosphere over the countryside than over the ocean, then over the city there are 150 times more of them.
Impact on the atmosphere of ferrous and non-ferrous metallurgy enterprises. The enterprises of the metallurgical industry saturate the atmosphere with dust, sulfur dioxide and other harmful gases released during various technological production processes.
Ferrous metallurgy, the production of cast iron and its processing into steel, naturally occurs with the accompanying emissions of various harmful gases into the atmosphere.
Air pollution with gases during the formation of coals is accompanied by the preparation of the charge and its loading into coke ovens. Wet quenching is also accompanied by the release into the atmosphere of substances that are part of the water used.
During the production of metallic aluminum by electrolysis, a huge amount of gaseous and dusty compounds containing fluorine and other elements are released into the environment. When smelting one ton of steel, 0.04 tons of solid particles, 0.03 tons of sulfur oxides and up to 0.05 tons of carbon monoxide enter the atmosphere. Non-ferrous metallurgy plants discharge into the atmosphere compounds of manganese, lead, phosphorus, arsenic, mercury vapor, vapor-gas mixtures consisting of phenol, formaldehyde, benzene, ammonia and other toxic substances. .
Impact on the atmosphere of petrochemical industry enterprises. Enterprises of the oil refining and petrochemical industries have a noticeable negative impact on the state of the environment and, above all, on the atmospheric air, which is due to their activities and the combustion of oil refining products (motor, boiler fuels, and other products).
In terms of air pollution, oil refining and petrochemistry rank fourth among other industries. The composition of fuel combustion products includes such pollutants as oxides of nitrogen, sulfur and carbon, carbon black, hydrocarbons, hydrogen sulfide.
During the processing of hydrocarbon systems, more than 1500 tons/year of harmful substances are emitted into the atmosphere. Of these, hydrocarbons - 78.8%; sulfur oxides - 15.5%; nitrogen oxides - 1.8%; carbon oxides - 17.46%; solids - 9.3%. Emissions of solid substances, sulfur dioxide, carbon monoxide, nitrogen oxides account for up to 98% of total emissions from industrial enterprises. As analysis of the state of the atmosphere shows, it is the emissions of these substances in most industrial cities that create an increased background of pollution.
The most environmentally hazardous are the industries associated with the distillation of hydrocarbon systems - oil and heavy oil residues, the purification of oils using aromatic substances, the production of elemental sulfur, and treatment facilities.
Impact on the atmosphere of agricultural enterprises. Atmospheric air pollution by agricultural enterprises is carried out mainly through emissions of polluting gaseous and suspended substances from ventilation installations that ensure normal living conditions for animals and humans in production facilities for keeping livestock and poultry. Additional pollution comes from boilers as a result of the processing and release of combustion products of fuel into the atmosphere, from exhaust gases from motor and tractor equipment, from fumes from manure storage tanks, as well as from spreading manure, fertilizers and other chemicals. It is impossible not to take into account the dust generated during the harvesting of field crops, loading, unloading, drying and finalizing bulk agricultural products.
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 installations 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. The emission of harmful substances into the atmosphere at oil refineries occurs mainly due to insufficient sealing of equipment. For example, atmospheric air pollution with hydrocarbons and hydrogen sulfide is noted from metal tanks of raw material parks for unstable oil, intermediate and commodity parks for light oil products.
The change in the gas composition of the atmosphere is the result of a combination of natural phenomena in nature and human activities. But which of these processes prevails at the present time? In order to find out, we first clarify what pollutes the air. Its relatively constant composition has been subject to significant fluctuations over recent years. Let's take a look at the main problems of emissions control and air cleanliness using the example of this work in cities.
Does the composition of the atmosphere change?
Standing next to a smoldering garbage heap is the same as being on the most gassed street in a metropolis. The danger of carbon monoxide is that it binds blood hemoglobin. The resulting carboxyhemoglobin can no longer deliver oxygen to the cells. Other substances that pollute the atmospheric air can cause disruption of the bronchi and lungs, poisoning, exacerbation of chronic diseases. For example, when carbon monoxide is inhaled, the heart works with an increased load, since not enough oxygen is supplied to the tissues. In this case, cardiovascular disease may worsen. An even greater danger is the combination of carbon monoxide with pollutants in industrial and transport emissions.
Pollutant concentration standards
Harmful emissions come from metallurgical, coal, oil and gas processing plants, energy facilities, construction and utilities industries. Radioactive contamination from explosions at the Chernobyl nuclear power plant and nuclear power plants in Japan has spread on a global scale. There is an increase in the content of carbon oxides, sulfur, nitrogen, freons, radioactive and other hazardous emissions in different parts of our planet. Sometimes toxins are found far away from the place where the enterprises that pollute the air are located. The situation that has arisen is an alarming and difficult to solve global problem of mankind.
Back in 1973, the relevant committee of the World Health Organization (WHO) proposed criteria for assessing the quality of atmospheric air in cities. Experts have found that the state of human health is 15-20% dependent on environmental conditions. Based on many studies in the 20th century, acceptable levels of the main pollutants that are harmless to the population were determined. For example, the average annual concentration of suspended particles in the air should be 40 µg/m 3 . The content of sulfur oxides should not exceed 60 µg/m 3 per year. For carbon monoxide, the corresponding average is 10 mg/m 3 for 8 hours.
What are Maximum Permissible Concentrations (MACs)?
The Decree of the Chief State Sanitary Doctor of the Russian Federation approved the hygienic standard for the content of almost 600 harmful compounds in the atmosphere of settlements. pollutants in the air, compliance with which indicates the absence of adverse effects on people and sanitary conditions. The standard specifies the hazard classes of compounds, the magnitude of their content in the air (mg / m 3). These indicators are updated when new data on the toxicity of individual substances become available. But that's not all. The document contains a list of 38 substances for which a ban on release has been introduced due to their high biological activity.
How is state control in the field of atmospheric air protection carried out?
Anthropogenic changes in the composition of the air lead to negative consequences in the economy, deteriorating health and shortening the life expectancy of people. The problems of increasing the entry of harmful compounds into the atmosphere are of concern to both governments, state and municipal authorities, and the public, ordinary people.
The legislation of many countries provides for before the start of construction, reconstruction, modernization of almost all economic facilities. Rationing of pollutants in the air is being carried out, measures are being taken to protect the atmosphere. The issues of reducing the anthropogenic load on the environment, reducing emissions and discharges of pollutants are being addressed. Russia has adopted federal laws on the protection of the environment, atmospheric air, and other legislative and regulatory acts regulating activities in the environmental sphere. State environmental control is carried out, pollutants are limited, and emissions are regulated.
What is PVD?
Enterprises that pollute the air should make an inventory of the sources of harmful compounds entering the air. Usually, this work finds its logical continuation when determining the need for obtaining this document is related to the regulation of the technogenic load on atmospheric air. On the basis of the information included in the MPE, the company receives a permit to release pollutants into the atmosphere. Data on regulatory emissions are used to calculate payments for negative environmental impact.
If there is no volume of MPE and a permit, then for emissions from pollution sources located on the territory of an industrial facility or another industry, enterprises pay 2, 5, 10 times more. Rationing of pollutants in the air leads to a reduction in the negative impact on the atmosphere. There is an economic incentive to carry out measures to protect nature from the ingress of foreign compounds into it.
Payments for environmental pollution from enterprises are accumulated by local and federal authorities in specially created budgetary environmental funds. Financial resources are spent on environmental activities.
How is the air cleaned and protected at industrial and other facilities?
Purification of polluted air is carried out by different methods. Filters are installed on the pipes of boiler houses and processing enterprises, there are dust and gas trapping installations. Through the use of thermal decomposition and oxidation, some toxic substances are converted into harmless compounds. Capture of harmful gases in emissions is carried out by condensation methods, sorbents are used to absorb impurities, catalysts for purification.
Prospects for activities in the field of air protection are associated with work to reduce the release of pollutants into the atmosphere. It is necessary to develop laboratory control of harmful emissions in cities, on busy highways. Work should be continued on the introduction of systems for trapping solid particles from gaseous mixtures at enterprises. We need cheap modern devices to clean emissions from toxic aerosols and gases. In the field of state control, an increase in the number of posts for checking and adjusting the toxicity of car exhaust gases is required. Energy industry enterprises and motor vehicles should be switched to less harmful, from the point of view of the environment, types of fuel (say, natural gas, biofuels). When they are burned, less solid and liquid pollutants are released.
What role do green spaces play in air purification?
It is difficult to overestimate the contribution of plants to the replenishment of oxygen reserves on Earth, to the capture of pollution. Forests are called "green gold", "lungs of the planet" for the ability of leaves to photosynthesis. This process consists in the absorption of carbon dioxide and water, the formation of oxygen and starch in the light. Plants emit phytoncides into the air - substances that have a detrimental effect on pathogenic microbes.
Increasing the area of green spaces in cities is one of the most important environmental measures. Trees, shrubs, herbs and flowers are planted in the courtyards of houses, in parks, squares and along roads. Landscaping the territory of schools and hospitals, industrial enterprises.
Scientists have found that plants such as poplar, linden, and sunflower absorb dust and harmful gaseous substances from the emissions of enterprises and transport exhausts best of all. Coniferous plantations emit the most phytoncides. The air in pine, fir, juniper forests is very clean and healing.
