Air pollution from motor vehicles. Negative impact of transport on the environment

Ministry of Education and Science of the Republic of Buryatia.

Municipal budgetary educational institution

"Nikolskaya secondary school"

Scientific and practical conference of students

"Step into the Future"

Ecology of the region.

Subject:

The role of the car in pollution

Supervisor:

Introduction.

Object of study: environment

Subject of study: cars.

Practical significance of the work: Preserving environmental quality and public health is among the most pressing problems of our time.

Target: study the influence of motor transport on the ecological state of the environment.

Tasks:

1. Consider the “contribution” of road transport to air pollution.

2. Determine the number (units) of vehicles passing along the road section.

4. Study the impact of road transport on the environment.

Hypothesis: To be or not to be cars.

Methods:

· Study of literature;

· Conversation with gas station employees, rural administration;

· Calculations using formulas.

Equipment: pen, microcalculator, notepad, phone with camera.

We must not allow people to direct their

own destruction are those forces of nature

which they were able to discover and conquer"

(F. Joliot - Curie, physicist, laureate

Nobel Prize.)

Environmental pollution has a history almost as long as the history of humanity itself. For a long time, primitive man differed little from other species of animals and, in an ecological sense, was in balance with the environment. Moreover, the human population was small. Over time, as a result of the development of the biological organization of people and their mental abilities, the human race stood out from other species: the first species of living beings arose, the impact of which on all living things represents a potential threat to the balance in nature. It can be considered that “human intervention in natural processes during this time has increased by no less than 5,000 times, if this intervention can be estimated at all.”

Emissions of harmful substances from motor vehicles are characterized by the amount of major air pollutants released into the atmosphere from exhaust gases over a certain period of time. The initial data for calculating the amount of emissions is:

1. the number of vehicles of different types passing along a designated section of the highway per unit of time;

2. vehicle fuel consumption rates (average vehicle fuel rates).

Having made the calculations, I received the following: (see Appendix Table 4 “Fuel consumption rates for vehicles when driving”, Table 5 « Emission of harmful substances from vehicles depending on the type of fuel")

I calculated the amount of fuel (Qi, l) of different types burned when driving by car engines, using the formula Qi = Li x Yi, took the value of Yi in table 4. The results were entered into table 6. (see appendix table 6 “Determination of the total amount of fuel burned each type")

Conclusion: determined the total amount of burned fuel of each type, it turned out that more gasoline is burned than diesel fuel.

While talking with employees of the Rosneft gas station from Nikolsk, I learned that 3 tons of gasoline and 2 tons of diesel fuel are consumed per day. A month produces 94 tons of gasoline and 67 tons of diesel fuel.

The next step in my work was to calculate the amount of harmful substances released in liters under normal conditions for each type of fuel and that’s it. This is what I got (see Appendix Table 7 “Amount of harmful substances released on the section of the federal highway from Nikolsk”):

Conclusion: analysis of Table 7 shows that on the section of the Moscow-Vladivostok federal highway the main air pollutants are gasoline-powered cars.

2. Processing of results and conclusions.

Processing the results:

1. calculated the mass of released harmful substances using the formula: m=V*M: 22.4

2. calculated the amount of clean air required to dilute the released harmful substances. The results were recorded in table No. 8 (see appendix table 8)

1. Reduce the content of harmful substances in exhaust gases.

It is environmentally cleaner to refuel cars not with gasoline, but with liquefied gas or alcohol; the exhaust from such cars is less dangerous. In the future, it will be possible to use hydrogen obtained from the decomposition of water.

In the future, the modern car will be replaced by an electric car and, of course, people will use bicycles and walk more often.

2. Use traffic efficiently.

3. Development of the most efficient urban transport route;

4. Full implementation of environmental and economic laws adopted in Russia and other countries.

4. Conclusion:

To be a car or not to be? The answer is clear - to be! The fight against automobile danger is currently underway. New filters are being designed, new types of fuel are being developed. We can only hope that in the near future humanity will be able to find ways to operate road transport without causing harm to the environment and human health. A person must change his life position in relationships with nature. From its conqueror and consumer, humanity must turn into a partner of its environment. An urgent need of our time is environmental literacy, ecological culture and ethics of all humanity, and first of all, citizens of Russia.

To reduce the harmful impact of cars on nature, you should:

1. Reduce the content of harmful substances in exhaust gases.

In the future, the modern car will be replaced by an electric car and, of course, people will use bicycles and walk more often.

2. Use traffic efficiently.

The largest amount of pollutants is emitted when a car accelerates, especially when driving quickly, as well as when driving at low speeds (from the most economical range). The relative share (of the total mass of emissions) of hydrocarbons and carbon monoxide is highest during braking and idling, the share of nitrogen oxides is highest during acceleration. From these data it follows that cars pollute the air especially heavily when stopping frequently and when driving at low speeds, so to reduce emissions, street traffic should be done non-stop.

3. Development of the most efficient urban transport route;

Freight transport routes should be moved out of the city onto bypass roads, and enter the city center only when necessary - to service shops, businesses, and transport people’s belongings. It is possible to create special pedestrian zones where vehicle traffic is prohibited.

4. Full implementation of environmental and economic laws adopted in Russia and other countries.

Environmental laws related to motor vehicles in force in Russia are described in Chapter 26 of the Criminal Code of the Russian Federation “Environmental Crimes”.

There are laws, but do car owners and manufacturers adhere to them? The answer suggests itself, since the cars used in the country do not comply with modern European toxicity limits and emit significantly more harmful substances than their foreign counterparts.

The absence of strict legal requirements for emission toxicity leads to the fact that the consumer is not interested in buying more environmentally friendly, but at the same time more expensive cars, and the manufacturer is not inclined to produce them.

Conclusion:

To be a car or not to be? The answer is clear - to be! The fight against automobile danger is currently underway.

1. Used Books:

2. , Tagasov safety of road transport-M, Publishing house "Nauchtekhlitizdat", 1999.

3. Aksyonov I. Ya., Aksyonov and environmental protection-M. "Transport", 1986

4. Ashikhmina environmental monitoring. M., “Agar”, “Rendezvous-AM”, 2000.

5., etc. Motor transport flows and the environment: Textbook for universities-M. INFRA-M, 1998

6. Gross ecology: Textbook. 2nd edition revised and expanded, “Dashkov and Co. Publishing House”, 2001

7. Kurov to reduce environmental pollution by motor transport? // Russia in the world around us - Analytical Yearbook, 2000.

8. Eichler V. Poisons in our food (translated from German) - M., “Mir”, 1993.

9. Encyclopedia for children. Ecology. M.: “Avanta +”, 2004

10. Encyclopedia for children. Chemistry. M.: “Avanta +”, 2004

11., “Fundamentals of Ecology”, M.: “Prosveshcheniye”, 1997.

12., Chemistry - 10, M.: “Enlightenment”, 2008.

13., Chemistry - 9, M.: “Enlightenment”, 2008.

14. Publishing House “First of September”, Chemistry, No. 14, No. 19, No. 22, No. 23, 2009.

15. , “The Beginnings of Chemistry”, M.: “Exam”, 2000.

Shishkov environmental problems. - M.: Knowledge, 1991. - p. 3

Ministry of General and Professional Education of the Sverdlovsk Region

branch of the state autonomous professional educational institution of the Sverdlovsk region "Karpinsky Mechanical Engineering College"

“The car as a source of chemical pollution of the atmosphere”

Introduction……………… …….. 3

1.Motor transport as a source of pollution…

1.1 Elements of pollution…… ………………………

1.2 Characteristics of the road

complex in Russia…………………………………………

2. Pollutants released into the atmosphere……….

2.1 Exhaust gases from engines, characteristics of groups.....

2.2 Characteristics of smog…… ………………….

3. The car as a cause of human illness… ………….

4. Reducing the impact of road transport on

environment…… ……………………………………………….

4.1 Main directions and ways to reduce harmful emissions from vehicles…….

4.2 Management of vehicle waste…

4.2.1 Waste management in foreign countries….

4.2.2 Organizational and technological diagram

waste disposal……. …………………………………………………………

4.2.3 Dismantling of vehicles to be disposed of…………………………………………………………

4.2.4 Sorting and disposal of rubber products……………………………………………………………….

Conclusion………………………………………………....

References……………………………………………………………...... 33

Introduction

Humanity is coming to realize the need for a radical transformation of its attitude towards the natural environment and its role in the world around us. Solving the environmental problems of modern society is associated with the preservation and creation of favorable natural living conditions for people on Earth, the harmonization of the development of society and nature.

Transport - one of the most important elements of the material and technical base of social production and a necessary condition for the functioning of a modern industrial society, since with its help the movement of goods and passengers is carried out. There are horse-drawn, automobile, agricultural (tractors and combines), railway, water, air and pipeline transport. Currently, the globe is covered by a network of communication routes. The length of the world's main paved roads exceeds 12 million km, air lines - 5.6 million km, railways - 1.5 million km, main pipelines - about 1.1 million km, inland waterways - more than 600 thousand. km. Sea lines are many millions of kilometers long. Along with the benefits that a developed transport network provides to society, its progress is also accompanied by negative consequences - the negative impact of transport on the environment, and above all on the troposphere, soil cover and water bodies. All vehicles with autonomous prime movers pollute the atmosphere to some extent from chemical compounds contained in exhaust gases. Road transport causes the greatest damage to the environment. In many large cities, such as Berlin, Mexico City, Tokyo, Moscow, St. Petersburg, Kyiv, air pollution from automobile exhausts accounts for, according to various estimates, from 80 to 95% of all pollution. As for air pollution by other types of transport, the problem here is less acute, since vehicles of these types are not concentrated directly in cities. Transport is one of the main pollutants of atmospheric air, water bodies and soil. Degradation and death of ecosystems occurs under the influence of transport pollution, especially intensely in urban areas. There is an acute problem of disposal and recycling of waste generated during the operation of vehicles, including at the end of their service life. Natural resources are consumed in large quantities for transport needs. The quality of the environment is decreasing due to increased noise pollution from transport. This predetermines the need to develop theoretical foundations and methodological approaches to solving environmental problems in the transport complex.

A modern car is an example of a non-eco-friendly vehicle. Therefore, it is most advisable to consider the problems and ways to improve the environmental friendliness of various types of transport using the example of road transport.

1. Motor transport as a source of air pollution

1.1 Elements of pollution

The transport and road complex is one of the most powerful sources of environmental pollution. In addition, transport is the main source of noise in cities, as well as a source of thermal pollution. The total global vehicle fleet is 800 million units, of which 83…85 % make up passenger cars, and 15…17% - trucks and buses. Exposed bumper to bumper, they would form a chain 4 million kilometers long, which could wrap around the globe 100 times along the equator. If the growth trends in the production of motor transport systems remain unchanged, then by 2020 the number of vehicles may increase to 1.5 billion units.

Motor transport, on the one hand, consumes oxygen from the atmosphere, and on the other hand, it emits exhaust gases, crankcase gases and hydrocarbons into it due to their evaporation from fuel tanks and leaky fuel supply systems. A car has a negative impact on almost all components of the biosphere: the atmosphere, water resources, land resources, lithosphere and humans. An assessment of environmental hazards through resource-energy variables of the entire life cycle of a car from the moment of extraction of mineral resources needed for its production to waste recycling after the end of its service showed that the environmental “cost” of a 1-ton car, in which approximately 2/3 mass is metal, equal to 15 before 18 tons of solid and from 7 before 8 tons of liquid waste disposed of in the environment. Exhausts from vehicles spread directly onto city streets along roads, having a direct harmful effect on pedestrians, residents of nearby buildings and vegetation. It was revealed that zones exceeding the maximum permissible amount of nitrogen dioxide and carbon monoxide cover up to 90% of the urban area.

A car is the most active consumer of air oxygen. If a person consumes up to 20 kg (15.5 m3) per day and up to 7.5 tons per year, then a modern car consumes about 12 m3 of air, or about 250 liters of oxygen in oxygen equivalent, to burn 1 kg of gasoline. Thus, in large cities, road transport absorbs oxygen tens of times more than their entire population. Studies conducted on Moscow highways have shown that in calm, windless weather and low atmospheric pressure on busy highways, the combustion of oxygen in the air often increases to 15% of its total volume. It is known that when the oxygen concentration in the air is below 17%, people develop symptoms of malaise, at 12% or less there is a danger to life, at a concentration below 11% loss of consciousness occurs, and at 6% breathing stops. On the other hand, on these highways there is not only little oxygen, but the air is also saturated with harmful substances from automobile exhaust. Research by the Research Institute of Normal Physiology shows that in Moscow 92...95% of air pollution comes from road transport. Smoke emitted by factory chimneys, fumes from chemical industries, fumes from boiler houses and all other waste from the activities of a larger city make up approximately only 7% of the total mass of pollution. A special feature of automobile emissions is that they pollute the air at the height of human growth, and people breathe these emissions. Gases released as a result of fuel combustion in internal combustion engines contain more than 200 names of harmful substances, including carcinogens. Petroleum products, residues from worn tires and brake pads, bulk and dusty cargo, chlorides, which are used to sprinkle roads in winter, pollute roadside strips and water bodies. It is difficult to imagine a modern person without a car. In developed countries, a car has long become the most necessary household item. The level of so-called “mobility” of the population has become one of the main economic indicators of the country’s development and the quality of life of the population. But we forget that the concept of “motorization” includes a complex of technical means that ensure movement: a car and a road. Nowadays, motor transport is the main source of air pollution in large cities. When operating vehicles, harmful substances enter the air with exhaust gases, fumes from fuel systems, and also during refueling of the vehicle. Emissions of carbon oxides (carbon dioxide and carbon monoxide) are also affected by the topography of the road, the mode and speed of the vehicle. For example, if you increase the speed of a car and sharply reduce it during braking, then the amount of carbon oxides in the exhaust gases increases 8 times. The minimum amount of carbon oxides is released at a uniform vehicle speed of 60 km/h. Thus, the content of harmful substances in exhaust gases depends on a number of conditions: vehicle traffic mode, road topography, technical condition of the car, etc. Now let’s refute one myth: a diesel engine is considered more environmentally friendly than a carburetor engine. But diesel engines emit a lot of soot, which is formed as a product of fuel combustion. This soot contains carcinogenic substances and microelements, the release of which into the atmosphere is simply unacceptable. Now imagine how much of these substances enters our atmosphere, if most of our trains are equipped with just such engines, which is why we inherited them from the Soviet Union.

Pollution of the earth's surface by transport and road emissions accumulates gradually, depending on the number of vehicles passing through the highway, road, highway, and persists for a very long time even after the elimination of the roadway (closure of the road, highway, highway or complete elimination of the track and asphalt surface). The future generation will probably abandon cars in their modern form, but transport soil pollution will be a painful and severe consequence of the past. It is possible that even with the elimination of the roads built by our generation, the soil contaminated with non-oxidizable metals and carcinogens will simply have to be removed from the surface.

Various chemical elements, especially metals, accumulating in the soil are absorbed by plants and through them pass through the food chain into the body of animals and humans. Some of them dissolve and are carried away by groundwater, then enter rivers and reservoirs and can enter the human body through drinking water. The most common and toxic of transport emissions is lead. The sanitary standard for lead content in soil is 32 mg/kg. According to environmentalists, the lead content on the soil surface near the Kyiv-Odessa highway in Ukraine is close to 1000 mg/kg, but in a city where traffic is very intense, this figure can be 5 times higher. Most plants easily tolerate an increase in the content of heavy metals in the soil; only when the lead content exceeds 3000 mg/kg does oppression of the plant world around the road begin. A content of 150 mg/kg of lead in food is dangerous for animals.

How can we protect the environment from transport? For example, in the USA they build protective strips 100 m wide on both sides of a highway or road where there is very heavy traffic. Over 10 years of operation of such a road, up to 3 kg of lead accumulates in its protective strips per meter. In Holland, it is allowed to use land for crops that is located at a distance of 150 m and further from the road, so they studied that within 150 m from the highway, an average of 5 mg/kg to 200 mg/kg of lead accumulates in plants.

Latvian scientists have found that at a depth of 5-10 cm the concentration of metals is lower than on the soil surface. Most emissions accumulate at a distance of 7-15 meters from the edge of the roadway; after 25 m the concentration decreases by approximately half, and after 100 m it approaches the norm. It is also worth paying attention to the fact that of the total emissions, 25% remains on the road surface itself, and the remaining 75% settles in the surrounding area.

Along with environmental pollution by harmful emissions, the physical impact on the atmosphere in the form of the formation of anthropogenic physical fields (increased noise, infrasound, electromagnetic radiation) should be noted. Of these factors, the most widespread impact is caused by increased noise. Noise levels are measured in decibels (dBA). For a person, the limit is 90 dBA; if the sound exceeds this limit, it can cause nervous disorders and constant stress in a person. Recently, traffic noise has become a very acute problem for the population. The main source of acoustic pollution of the environment is road transport: its contribution to acoustic pollution in cities ranges from 75 to 90%. It is believed that 60-80% of noise in the city comes from vehicle traffic. In large cities, the noise level reaches 70...75 dBA, which is several times the permissible norm. The general noise level on our roads is higher than in the West. This is a consequence of the fact that there are too many trucks in the traffic flow, the noise level of which is 8-10 dBA, i.e. twice as high as for passenger cars. But the main reason is the lack of noise control on the roads. There are no requirements to limit noise even in the Traffic Rules. It's no wonder that improperly equipped trucks and poorly secured loads have become a widespread phenomenon on the roads. Sometimes a truck carrying about two dozen gas pipes makes more noise than a pop orchestra.

Sources of noise while driving are the power unit, intake and exhaust systems, transmission unit, wheels in contact with the road surface. The noise characteristics of vehicles while driving on the road reveal the technical level and quality of the road surface. Now let’s remember our national disaster: bad roads with potholes, numerous patches, puddles, ditches, etc. So, a bad road is not only a problem for motorists and transport workers, it is also an environmental problem.

1.2 Characteristics of the automobile and road complex in Russia

Road transport serves as a means of communication between the place of residence and place of work, shops, places of entertainment and recreation. Settlements and economies necessitate the development of transport, and new communication routes and technical improvements in transport, in turn, contribute to the development of settlements and economies. The high speeds provided by the car and the developed road network have given modern man greater mobility. The development of transport, construction and maintenance of transport infrastructure increase harmful loads on the environment and people through noise, air pollution, landscape destruction and accidents.

There is a steady upward trend in the number of vehicles in personal use. The average age remains significant, 10% of the fleet has been in operation for over 13 years, is completely worn out and is subject to write-off. Such operation leads to wasteful fuel consumption and increased emissions of pollutants into the atmosphere.

The achieved level of motorization in Russia is currently 2 - 4 times lower than this level in Western countries. Car models produced in Russia are 8 to 10 years behind in all key indicators (efficiency, environmental friendliness, reliability, safety) from cars produced in industrialized countries. In addition, domestically produced vehicles do not meet modern environmental requirements. Given the rapid growth of the vehicle fleet, this leads to an even greater increase in the negative impact on the environment.

The composition of the vehicle fleet by type of fuel used also remained the same. The share of cars using gas fuel does not exceed 2%. The share of trucks with diesel engines is 28% of their total number. For the Russian bus fleet, the share of buses running on diesel fuel is approximately 13%.

The condition of roads in Russia as a whole is unfavorable. New roads are being built extremely slowly. Over long distances, road sections have unsatisfactory smoothness, evenness and strength. This creates the preconditions for the occurrence of transport accidents.

In the infrastructure of the transport industry, there are about 4 thousand large and medium-sized motor transport enterprises engaged in passenger and freight transportation. With the development of market relations, commercial transport units of small capacity appeared in large numbers. They carry out automobile transportation, vehicle maintenance and repair, provide maintenance services and carry out other activities. The growth of the vehicle fleet, changes in forms of ownership and types of activities did not significantly affect the nature of the impact of vehicles on the environment.

The bulk (80%) of harmful substances are emitted by vehicles in populated areas. It still remains a leader in urban air pollution. In the mid-00s, motor transport in Russia accounted for 80% of lead emissions, 59% of carbon monoxide, and 32% of nitrogen oxides.

2. Pollutants released into the atmosphere

2.1 Engine exhaust gases, characteristics of groups

Emissions from cars include about 200 chemical compounds, which, depending on the specific effects on the body, are divided into 7 groups. The period of their existence lasts from several minutes to 4 - 5 years.

To the first group includes non-toxic chemical substances contained in the natural composition of atmospheric air: nitrogen, oxygen, hydrogen, water vapor, carbon dioxide and other natural components of atmospheric air. Motor vehicles emit such a huge amount of steam into the atmosphere that in Europe and the European part of Russia it exceeds the evaporation mass of all reservoirs and rivers. Because of this, cloudiness increases, and the number of sunny days noticeably decreases. Gray, sunless days, unheated soil, constantly increased air humidity - all this contributes to the growth of viral diseases and a decrease in agricultural yields.

To the second group include only one substance - carbon monoxide, or carbon monoxide (CO). This is a colorless, tasteless and odorless gas, a product of incomplete combustion of petroleum fuels, very slightly soluble in water, lighter than air. Carbon monoxide has a pronounced toxic effect. Inhaled by a person, it combines with hemoglobin in the blood and suppresses its ability to supply the body's tissues with oxygen. As a result, oxygen starvation occurs in the body and disturbances in the activity of the central nervous system occur. The effects of exposure depend on the concentration of carbon monoxide in the air; Thus, at a concentration of 0.05%, after 1 hour signs of mild poisoning appear, and at 1%, loss of consciousness occurs after several breaths. Drivers of vehicles are often susceptible to carbon monoxide poisoning when spending the night in the cab with the engine running or when warming up the engine in a closed garage.

To the 3rd group includes nitrogen oxide (MPC 5 mg/m3, 3cl.) - a colorless gas and nitrogen dioxide (MPC 2 mg/m3, 3cl.) - a reddish-brown gas with a characteristic odor. These gases are formed in the combustion chamber of an internal combustion engine at a temperature of 2800. They are impurities that contribute to the formation of smog. Nitrogen oxides are even more harmful to the human body than carbon monoxide. Once in the human body, they, interacting with moisture, form nitrous and nitric acids (MPC 2 mg/m3, 3 cells). The consequences of exposure depend on their concentration in the air, so, at a concentration of 0.0013%, slight irritation of the mucous membranes of the eyes and nose, at 0.002% - the formation of meta-hemoglobin, at 0.008 - pulmonary edema, with high concentrations of nitrogen oxides, asthmatic manifestations occur. When inhaling air containing nitrogen oxides in high concentrations, a person does not have any unpleasant sensations and does not expect negative consequences.

Fourth group. This group includes various hydrocarbons, that is, compounds of the SCN type. They are formed as a result of incomplete combustion of fuel in the engine. Hydrocarbons are toxic and have adverse effects on the human cardiovascular system. Hydrocarbon compounds in exhaust gases, along with toxic properties, have a carcinogenic effect. The most dangerous of them is 3,4 - benz(a)pyrene (MPC 0.00015 mg/m3, 1 cell) - a powerful carcinogen. Under normal conditions, this compound is yellow needle-shaped crystals, poorly soluble in water and well soluble in organic solvents. In human serum, the solubility of benzo(a)pyrene reaches 50 mg/ml.

To the fifth group includes aldehydes, organic compounds containing an aldehyde group associated with a hydrocarbon radical. The largest amount of aldehydes is formed at idle and low load modes, when combustion temperatures in the engine are low. The most dangerous of them are acrolein and formaldehyde. Acrolein is an aldehyde of acrylic acid (MPC 0.2 mg/ml3, 2 cells) - colorless, with the smell of burnt fat and a very volatile liquid that dissolves well in water. A concentration of 0.00016% is the threshold for odor perception, at 0.002% the odor is difficult to tolerate, at 0.005% the odor is difficult to tolerate, and at 0.014% death occurs after 10 minutes. Formaldehyde (MPC 0.5 mg/m3, 2 cells) is a colorless gas with a pungent odor, easily soluble in water. At a concentration of 0.007% it causes mild irritation of the mucous membranes of the eyes and nose, as well as the upper respiratory organs; at a concentration of 0.018% the breathing process is complicated.

To the sixth group includes soot (maximum concentration limit 4 mg/m3, 3 cells), which has an irritating effect on the respiratory system, and other dispersed particles (engine wear products, aerosols, oils, carbon deposits, etc.). Soot is black solid carbon particles formed during incomplete combustion and thermal decomposition of fuel hydrocarbons. By creating a smoky plume behind a vehicle, soot impairs visibility on the roads. Research conducted in the USA revealed that 50...60 thousand people die annually from soot air pollution. It was found that soot particles actively absorb benzo(a)pyrene on their surface, as a result of which the health of children suffering from respiratory diseases, as well as the elderly, deteriorates.

To the seventh group includes sulfur compounds - inorganic gases such as sulfur dioxide, hydrogen sulfide, which appear in engine exhaust gases if fuel with a high sulfur content is used. Significantly more sulfur is present in diesel fuels compared to other types of fuels used in transport. Sulfur compounds have an irritating effect on the mucous membranes of the throat, nose, and eyes of a person; they can lead to disruption of carbohydrate and protein metabolism and inhibition of oxidative processes, and at high concentrations (over 0.01%) - to poisoning of the body.

To the eighth group includes lead and its compounds - found in the exhaust gases of carburetor cars only when using leaded gasoline. Tetraethyl lead is added to gasoline as an anti-knock additive (MPC 0.005 mg/m3, 1 class). Therefore, about 80% of lead and its compounds that pollute the air enter it when using leaded gasoline. Lead and its compounds reduce the activity of enzymes and disrupt metabolism in the human body, and also have a cumulative effect, i.e. ability to accumulate in the body. Lead compounds are especially harmful to the intellectual abilities of children. Up to 40% of the compounds that enter it remain in the child’s body. In roadside areas, approximately 50% of lead emissions in the form of microparticles are immediately distributed on the adjacent surface. The remaining amount remains in the air in the form of aerosols for several hours, and then also settles on the ground near roads. The accumulation of lead in roadside areas leads to pollution of ecosystems and makes nearby soils unsuitable for agricultural use. Adding the R-9 additive to gasoline makes it highly toxic. In developed countries, the use of leaded gasoline is limited or has already been completely phased out. For example, in the USA the use of leaded gasoline is prohibited everywhere, and in Russia only in Moscow, St. Petersburg and a number of other large cities. However, the task is to abandon its use. Large industrial centers and resort areas are switching to the use of unleaded gasoline. Not only the considered components of engine exhaust gases, divided into eight groups, but also hydrocarbon fuels, oils and lubricants themselves have a negative impact on ecosystems. In places where vehicles are refueled with fuel and oil, accidental spills and intentional discharges of used oil occur directly onto the ground or into water bodies. Vegetation does not grow at the site of the oil stain for a long time.

2.2 Characteristics of smog

Under the influence of ultraviolet radiation from the sun, hydrocarbons react with nitrogen oxides, resulting in the formation of new toxic products - photooxidants, which are the basis of smog. Smog (from the English smoke - smoke and fog - fog).

Based on the nature of the action, two types of smog began to be distinguished: the Los Angeles type - dry and the London type - wet.

Such smog is formed in the atmosphere under the influence of sunlight in the absence of wind and low humidity from components characteristic of vehicle exhaust gases. Smog was first recorded in 1944 in Los Angeles, when, as a result of a large accumulation of cars, life in one of the largest cities in the United States was paralyzed. As a result of photochemical reactions, compounds are formed that cause wilting and death of plants, severely irritating the mucous membranes of the respiratory tract and eyes. Los Angeles-type smog increases the corrosion of metals and the destruction of building structures, rubber and other materials. Ozone and other substances formed in it give the oxidative character to this smog. Studies conducted in Los Angeles in the 1950s showed that increases in ozone concentrations were associated with a characteristic change in the relative amounts of NO2 and NO.

In 1952, the phenomenon of smog was observed in London. Fog itself is not dangerous for the human body, however, in urban conditions, with the continuous flow of smoke into the ground layers of the atmosphere, several hundred tons of soot (one of the culprits of temperature inversion) and substances harmful to human breathing, the main of which was sulfur dioxide, accumulated in them. gas.

London (wet) smog is a combination of gaseous and particulate matter with fog - the result of burning large quantities of coal (or fuel oil) in high atmospheric humidity. Subsequently, practically no new substances are formed in it. Thus, toxicity is entirely determined by the original pollutants.

British experts recorded that the concentration of sulfur dioxide SO2 in those days reached 5-10 mg/m3 and higher, with the maximum permissible concentration of this substance in the air of populated areas being 0.5 mg/m3. Mortality in London rose sharply on the first day of the disaster, and after the fog passed it dropped to normal levels. It was also found that citizens over 50 years of age, people suffering from lung and heart diseases, as well as children under the age of one year died first.

Accurate data about the events of those days is the result of the fact that by this time air research had been carried out for several decades, because the problem of gas pollution in London had existed for a long time.

The lesson from the 1952 tragedy was learned quite quickly. In 1956, a clean air law was passed and strictly enforced, and by 1970, soot emissions (the culprit of atmospheric inversion) had been reduced by 13 times. As a result, not a trace remained of the former London fogs. There are cases when there is less fog in the city center than in its surroundings, although the problem of pollution with sulfur oxides remains.

Subsequently, smog periodically appeared in many of the world's largest cities.

3. The car as a cause of human illness

The main problem of large cities is the significant increase in the incidence of chronic diseases among the population. In particular, respiratory diseases such as asthma, bronchitis and allergic rhinitis. The increase in motor transport significantly increases the risk of morbidity. In this publication we will consider motor transport as a source of pollution. Where does danger lie in wait for us?

We are accustomed to believing that the main pests to human health are exhaust gases and the harmful substances they contain. But few people think about what materials the interior trim elements are made of. Cleaning products that are used to clean the interior of vehicles also play an important role. When choosing a car, you need to ask what material is used in the production of interior decoration and interior design. You should also carefully study the composition of auto chemicals and follow the instructions for its use.

It is known that for the manufacture of car interior trim elements, materials are used that contain formaldehyde and acids, which emit quite harmful substances. Paints and varnishes contain solvents, the vapors of which are also harmful to human health. Unfortunately, not all manufacturers indicate the entire range of substances used in production. Subsequently, such materials have a detrimental effect on the driver’s well-being, and the release of harmful fumes can cause chronic diseases.

When choosing a vehicle, it is necessary to take into account not only its appearance and interior aesthetics. First of all, sit in the cabin and close the door. The presence of a strong unpleasant odor inside the cabin indicates a large number of low-quality interior elements.

It is also very important to use vehicle interior cleaning products that are of proper quality and intended only for use on surfaces of that material.

The use of glass washer fluids leads to the penetration of their vapors into the interior. When choosing a glass washer fluid, carefully study the composition of this product. The composition should not contain substances such as methanol. In Russia, the use of methanol is prohibited, as this substance is very toxic. Its vapors strongly irritate the mucous membranes and can cause a significant deterioration in health, including convulsions. Ingestion of methanol can cause severe poisoning and lead to loss of vision. Many manufacturers do not indicate the true composition of the substances included in the anti-freeze product. Therefore, if you are not sure of the quality of such a substance, then take the advice and fill the vehicle windshield washer tank with a solution of water and inexpensive vodka, adding a little detergent. You should also properly store automotive hygiene products.

Motor vehicles are a source of pollution and when brake pads act, a number of harmful substances are released, such as copper, zinc, and molybdenum. Used in the construction of pads, asbestos releases toxic substances that can cause cancer. To avoid the penetration of harmful compounds into the car interior, it is necessary to use filters. The effectiveness of their use depends on the degree of sealing of the vehicle interior and timely replacement of filters.

It should be noted that the presence of an air conditioner and an air ionizer in the car interior does not protect the human body from the harmful effects of harmful fumes. The air conditioner only serves to cool the air, and the use of an ionizer in the cabin can cause even more harm. Ionization of polluted air is, in principle, harmful.

No matter how strange it may sound, the main source of pollution from motor vehicles is not exhaust gases, but car tires. In general, rubber parts are not harmful to the environment and do not pose any danger to human health. But the interaction of rubber with other substances can lead to the formation of harmful compounds. Substances generated when vehicle tires adhere to the road surface can cause significant harm to health. Since they easily penetrate the respiratory tract, they can cause an allergic reaction. During braking, various toxic compounds are released, the names of which are scary. The harm they cause to all living things is also enormous. Imagine that in a big city the emission of tire dust per day reaches several tons. It settles on roads and sidewalks, and rises in hot, dry weather. This dust enters the respiratory tract and is deposited in the body for a long time. And it should be noted that such dust remains in our body for a long time. The amount of formation of such a harmful substance directly depends on the quality of the tire rubber itself, the correct adjustment of the vehicle’s chassis, the driver’s driving style and compliance with operating rules. The more evenly a tire tread wears, the less tire dust is generated.

It is also worth paying attention to the “quality” of the exhaust gases. When gasoline fuel burns, about 200 harmful substances are released. The most toxic are nitrogen and carbon oxides, organic compounds and heavy metals. When checking vehicle exhaust pollution, only the percentage of hydrocarbons and carbon monoxide is taken into account. For diesel cars, the soot content is also checked. A large content of harmful substances is concentrated at a distance of 50 - 150 cm from the ground, so it is not difficult for them to easily enter the human body, you just need to inhale.

Since carbon monoxide is colorless and odorless, humans cannot detect its presence in the air. However, the gas begins its dirty work, which can result in oxygen starvation of a person. Dizziness, nausea, vomiting, headache and slow driver reaction are the main signs of carbon monoxide poisoning. Incomplete combustion of fuel carbon leads to the formation of carbon monoxide. Even a short stay in a room (or inside a vehicle) with a high concentration of carbon monoxide can lead to death. A lethal concentration of this harmful substance in a garage can form within 2-3 minutes after starting the starter.

A high content of nitrogen oxide in the air of large cities or busy highways is indicated by the formation of smog that hangs over the road. The sky does not seem blue, but gray. This harmful substance is formed during the combustion of any type of fuel. Such a gas, entering the human body, irritates the respiratory organs and mucous membranes, and can be the causative agent of serious lung diseases. The most nitrogen oxide is released when a vehicle engine is idling while standing idle in city traffic jams and waiting for the right traffic light signal. Large concentrations of this pollution from motor vehicles indoors cause pulmonary edema and death.

4. Reducing the impact of road transport on the environment

4.1 Main directions and ways to reduce harmful emissions from vehicles

The priority areas for reducing environmental pollution by road transport are:

The use of new types of vehicles that minimally pollute the environment (for example, electric cars);

Rational organization and management of traffic flows;

Use of higher quality or environmentally friendly fuels (for example, gas);

The use of advanced systems - fuel catalysts and noise suppression systems - noise mufflers.

All measures to reduce emissions from motor vehicles are divided into technological, sanitary, planning, and administrative. Technological measures include: fuel replacement, engine replacement, improvement of the engine operating process, modern maintenance. Sanitary and technical: exhaust gas recirculation, exhaust gas neutralization. Planning includes the organization of street intersections on different roads, the organization of underground (overground) pedestrian crossings, as well as landscaping of highways and streets. Administrative measures include establishing standards for fuel quality and permissible regional emissions, removing transit transport, warehouses and terminals from the city, allocating lanes for public vehicles and non-stop highways.

There are two main directions for improving the environmental friendliness of road transport. The first is associated with the technical improvement of internal combustion engines (ICE) and the organization of rational traffic, and the second is with the development of hybrid vehicles and electric vehicles equipped with inertial drives.

Technical improvement of internal combustion engines is carried out in the following areas: fuel economy, introduction of additives into fuel, use of combined and new types of fuel, exhaust gas purification.

In the complex of technological measures to reduce harmful emissions from motor vehicles, an important place is occupied by the development of technologies for deep purification of gasoline and diesel fuel from sulfur and some heavy metals, in particular vanadium, directly at oil refining enterprises. The next independent task is adjusting the engines. It is known that a well-tuned engine improves fuel combustion characteristics by 30...40%, which leads to a reduction in emissions of harmful substances. Engine adjustment is performed in the process of specialized work in stationary conditions.

Based on the foregoing, it should be emphasized that the essence of environmental safety of motor vehicles lies in environmentally friendly fuel, high efficiency of its use in all engine operating modes, quality of the road surface, driver experience and optimal traffic control.

Neutralizers play an important role in the system for reducing harmful emissions. In combination with gasoline with improved environmental characteristics, diagnostic and engine adjustment systems, neutralizers complete the set of necessary technical systems for environmental safety of vehicles.

Another important aspect (from an environmental and economic point of view) of the problem under consideration is the recycling of vehicle waste, since, while causing damage to the environment, they are at the same time a valuable secondary product.

4.2 Management of vehicle waste

4.2.1 Waste management in foreign countries

Objects that have a negative impact on the environment include waste vehicles (VVW): worn-out vehicles and their replacement parts (tires, batteries, housings, frames, assemblies, etc.). It is known that the basis of waste from a passenger car, for example, weighing 800 kg, is made up of ferrous and non-ferrous metals in quantities equal to 71.1 and 3.4%, respectively, polymer materials - 8.5%, rubber - 4.7%, glass - 4 %, paper and cardboard - 0.5%, other materials, including hazardous chemical compounds - 7.8%.

The problem of PBX recycling is acute for many countries. In the European Union countries, vehicle waste is formed into a separate stream. The handling of them is clearly regulated by legal acts and controlled by government agencies, and is regulated economically - enterprises are responsible for processing the products they produce. The necessary funds for waste processing are allocated by the state (through the collection of taxes from car owners and importing companies) and accumulated in special environmental funds at the local federal level.

There is no consensus among economically developed countries in choosing ways to solve this problem. Some, for example Switzerland, consider an OATS scheme based on the selective collection and processing of easily recyclable materials to be economically feasible. This allows up to 75% of the waste to be recycled; the remaining 25% of waste is disposed of in landfills or incinerated along with municipal solid waste. Other countries (Germany, Italy) are achieving maximum recycling of OATS (for some materials up to 99%), using recycling, the introduction of new waste-free technologies and standardization of production products.

According to international standards, the acceptable service life of passenger cars is 10 years, after which they must be sent for recycling. In Switzerland, where about 250 thousand old passenger cars are generated annually, the scheme for organizing the flow of vehicular vehicles, as a rule, begins with waste collection sites.

Vehicle dismantling and selective collection of materials releasing hazardous waste are carried out by repair shops that have a state license to perform these types of work. From the general flow of vehicle vehicles, conditioned units and parts (for recycling or sale), batteries, and used tires are selected. The remaining waste (body, frame and other large parts of the car) is sequentially processed by pressing, cutting, crushing, and the resulting crushed fraction is subjected to separation by magnetic catchers to separate scrap metal. Next, the PBXs collected into separate streams are sent for processing.

Scrap metal is sorted into ferrous and non-ferrous metals, which are subsequently sent for smelting. In this way, 114 thousand tons of ferrous and 12 thousand tons of non-ferrous metals are processed in Switzerland.

Every year, 3.5 million new tires enter the Swiss domestic market. The mileage life of each tire is 40 thousand km, after which it is withdrawn from further use. This situation contributes to the accumulation of 50...60 thousand tons of used tires, of which 21 thousand tons are exported for processing to other countries, 17 thousand tons are burned in asphalt concrete plants, 12 thousand tons after grinding are used as noise-absorbing material during construction roads, laying railway and tram tracks and only a small part of them is recycled.

In Switzerland, about 700 thousand tons of used batteries are generated annually. The acids they contain (4 thousand tons) are neutralized. Lead associated with antimony (8 thousand tons) is exported for processing to other countries, and polymer waste (1.4 thousand tons) is destroyed by high-temperature combustion.

4.2.2 Organizational and technological scheme of waste disposal

The OATS movement begins with waste collection sites. Some of these sites, equipped with cutting and pressing equipment for preliminary processing of waste (to increase the efficiency of their storage and transportation), can be converted into sorting and storage warehouses. The latter are necessary both for qualified sorting of waste, which often determines the efficiency of their further processing, and for the elimination of environmentally hazardous components of the vehicle.

Productive and mutually beneficial functioning of waste collection sites and corresponding sorting and storage warehouses involves the deployment of an information and expert system (IES) that determines the structure, characteristics and volumes of secondary raw materials needed by processors and other consumers.

Next, with the help of a regional stock exchange system for inventory and redistribution of secondary resources based on the IES, the flows of collected waste are managed in the areas of their technological processing.

4.2.3 Dismantling of vehicles subject to disposal

Dismantling of vehicles can be considered as an independent direction of vehicle vehicle processing, especially when there are constant flows of worn-out or substandard vehicles. All work on disassembling the vehicle into its component parts (frame, cab, engine, wheels, etc.) must be carried out at specialized enterprises.

Before disassembling the vehicle, it is advisable to divide it into 4 technological streams, differing in design and the possibility of using specialized disassembly stations: cars, buses, trucks, trailers and semi-trailers. These flows are not the same in quantity, so disassembly areas, along with specialization, must also have a certain versatility. Sufficient versatility should be the main principle of organizing work and equipping all dismantling areas of the enterprise with technological equipment. For example, in the trailer and semi-trailer dismantling area, with minor retrofitting, trucks can also be dismantled. Retrofitting concerns only auxiliary equipment, and first of all, additional equipment with lifting vehicles with special grips for removing the engine, cabin, etc.

Disassembled products can be fed to areas and moved along them using plate conveyors, which are most convenient for this type of work. It is advisable to equip the conveyors of dismantling shops with a drive with periodic action (movement). This is due to the possibility of a fairly wide variation in the complexity of dismantling operations.

Work stations in dismantling areas must be equipped with tippers, cantilever rotary cranes, impact wrenches of various capacities and sizes, and metal cutting devices. The latter are used if threaded ones cannot be disassembled using impact wrenches. Dumpers are necessary to provide access to vehicles when removing axles, gearboxes, steering gears, etc.

4.2.4 Sorting and disposal of rubber products

Restoration of worn tires.

Currently, in most developed countries, the problems of recycling used tires are attracting increasing attention.


	Annual number of worn tires, thousand tons


Germany

Annual number of worn tires in highly developed countries.

Thus, in the EU countries, about 15% of used tires for passenger cars and more than 50% of truck tires are retreaded, which is 20% cheaper than the production of new tires, without deteriorating their performance characteristics. Repeated retreading of large tires is especially effective, since their operating costs often exceed the initial cost of the vehicle.

Use of whole used tires and their pieces.

Foreign studies have shown that tires practically do not pollute water and their predicted durability in calm water reaches hundreds of years, which is why they are even used to create artificial spawning grounds for fish, and in France, to strengthen the soil (several hundred such engineering structures operate successfully). During the environmental and economic examination of projects, designers should be recommended to use worn tires and their pieces, which will allow saving financial resources several times, and primary building materials (cement, crushed stone, etc.) - tens of times. Worn tires are especially promising:

To protect against soil and coastal erosion (reclamation of ravines, construction of dams and other enclosing structures);

In the construction of bridges and culverts in the road industry;

When creating soundproofing barriers - screens on roads;

For strengthening “weak” soils in wide-profile engineering structures.

In combination with plastics, pieces of used tires can be used to make special mats and hoses for subsurface irrigation systems and agricultural drainage.

Use of crushed vulcanizers.

Ground vulcanizers are used in polymer mixtures for the production of construction and technical materials as additives in road surfaces and in various technological processes.

Grinding vulcanizers with a dispersion of 0.007 to 1.5 mm are widely used in the manufacture of shoes, tires, rubber coatings, mats and paths, linoleum, tile materials, composite materials with thermoplastics, bicomponent fillers of rubber products and as adsorbents. In Russia, about 74 thousand tons/year of crushed vulcanizers are consumed; with the expansion of work on their surface modification, the volume of use will increase significantly.

Despite the increase in the cost of work from 10 to 100%, rubber asphalt has greater wear and frost resistance, reduces noise and braking distance of the car. The Transportation Bill (USA) supported the use of rubber asphalt, which allowed the use of up to 30% of the used tires accumulated annually in the United States.

Coarse and mixed crushed vulcanizers can be widely used as mulch for agriculture, since they retain moisture better than organic matter, and as an additive to compost. Additives of crushed vulcanizers are promising for forming the surface of artificial and grass sports fields with a given elasticity. The use of crushed vulcanizers as sorbents for chemical and fuel and lubricant wastes and pollutants is expanding.

Thermal destruction of worn tires and rubber technical products.

Temperature destruction has applications, its main types include pyrolysis (a high-temperature process of destruction of molecules of starting substances) and destructive hydrogenation (processing in the presence of catalysts during a hydrogenation reaction - the splitting of raw material molecules with the addition of hydrogen to them).

Use of waste rubber technical products and tires as energy carriers.

Burning used tires is energetically unpromising, since the production of a passenger tire requires the energy contained in 35 liters of oil, and when it is burned, the energy returned is equivalent to only 8 liters of oil, i.e. polymerization costs are not covered. However, burning tires in cement kilns reduces environmental pollution and in some cases is economically beneficial.

Conclusion

In my essay, I talked about how motor transport is the most powerful source of environmental pollution; at the end, I want to summarize the results of my work. So, the number of cars in Russia is increasing, although a third of the fleet is badly worn out and must be written off. The transport and road complex is the most important component of the Russian economy. But its functioning is accompanied by a powerful negative impact on nature.

Transport is one of the main air pollutants. Its share in the total volume of emissions of pollutants into the atmosphere from stationary and mobile sources in Russia is about 70%, which is higher than the share of any industry. Motor transport emits 280 thousand tons of pollution per year, which is four times more than the permissible standards in Russia. During engine operation, a large amount of harmful substances are released into the environment, such as nitrogen, carbon monoxide, hydrocarbons, aldehydes, soot, sulfur compounds, and lead.

Bibliography

1) Lukanin V.N., Buslaev A.P., Trofimenko Yu.V. and others. Motor transport flows and the environment: Textbook for universities. M.: INFRA-M, 1998 - 408 p.

2) Aksenov I.Ya. Aksenov V.I. Transport and environmental protection. - M.: Transport, 1986. - 176 p.

3) Grigoriev A.A. Cities and the Environment. Space research. - M.: Mysl, 1982.

The transport and road complex is one of the most powerful sources of environmental pollution. In addition, transport is the main source of noise in cities, as well as a source of thermal pollution.

Gases released as a result of fuel combustion in internal combustion engines contain more than 200 types of harmful substances, including carcinogens. Petroleum products, residues from worn tires and brake pads, bulk and dusty cargo, chlorides, which are used to sprinkle roads in winter, pollute roadside strips and water bodies.

It is difficult to imagine a modern person without a car. In developed countries, a car has long become the most necessary household item. The level of so-called “mobility” of the population has become one of the main economic indicators of the country’s development and the quality of life of the population. But we forget that the concept of “motorization” includes a complex of technical means that ensure movement: a car and a road.

Nowadays, motor transport is the main source of air pollution in large cities.

When operating vehicles, harmful substances enter the air with exhaust gases, fumes from fuel systems, and also during refueling of the vehicle. Emissions of carbon oxides (carbon dioxide and carbon monoxide) are also affected by the topography of the road, the mode and speed of the vehicle. For example, if you increase the speed of a car and sharply reduce it during braking, then the amount of carbon oxides in the exhaust gases increases 8 times. The minimum amount of carbon oxides is released at a uniform vehicle speed of 60 km/h.

Thus, the content of harmful substances in exhaust gases depends on a number of conditions: vehicle traffic patterns, road topography, technical condition of the vehicle, etc.

Now let’s refute one myth: a diesel engine is considered more environmentally friendly than a carburetor engine. But diesel engines emit a lot of soot, which is formed as a product of fuel combustion. This soot contains carcinogenic substances and microelements, the release of which into the atmosphere is simply unacceptable. Now imagine how many of these substances enter our atmosphere, if most of our trains are equipped with just such engines, because we inherited from the Soviet Union V.G. Glushkova, A.T. Shevchenko. Ecological and economic problems of Russia and its regions. M.: Moscow Lyceum, 2002.S. 63. .

Exhaust gases accumulate in the lower layers of the atmosphere, that is, harmful substances are in the human breathing zone. Therefore, road transport should be classified as a dangerous source of air pollution near highways.

The most common and toxic of transport emissions is lead. The sanitary standard for lead content in soil is 32 mg/kg. According to environmentalists, the lead content on the soil surface near the Kyiv-Odessa highway in Ukraine is close to 1000 mg/kg, but in a city where traffic is very intense, this figure can be 5 times higher. Most plants easily tolerate an increase in the content of heavy metals in the soil; only when the lead content exceeds 3000 mg/kg does oppression of the plant world around the road begin. A content of 150 mg/kg of lead in food is dangerous for animals.

Transport not only pollutes the environment, it is also a source of noise.

Noise levels are measured in decibels (dBA). For a person, the limit is 90 dBa; if the sound exceeds this limit, it can cause nervous disorders and constant stress in a person. Recently, traffic noise has become a very acute problem for the population.

The general noise level on our roads is higher than in the West. This is a consequence of the fact that there are too many trucks in the traffic flow, the noise level of which is 8-10 dBa, i.e. twice as high as for passenger cars. But the main reason is the lack of noise control on the roads. There are no requirements to limit noise even in the Traffic Rules. It's no wonder that improperly equipped trucks and poorly secured loads have become a widespread phenomenon on the roads. Sometimes a truck carrying about two dozen gas pipes makes more noise than a pop orchestra.

It is believed that 60-80% of noise in the city comes from vehicle traffic.

Environmental problems of motor transport

The increasing car park in our country in recent years constantly reminds everyone, especially in large populated areas, that motor vehicles are one of the most significant environmental pollutants. In the Republic of Uzbekistan, this situation has arisen due to the lack of a unified state policy aimed at stimulating the development and implementation of advanced technologies to reduce the toxicity of engines and motor fuels. Domestic cars are morally outdated, but the industry continues to produce extremely toxic carburetor engines, while firms in industrialized countries have mastered the production of more economical and less toxic gasoline engines with direct injection and electronic control of the process of formation of the air-fuel mixture. The range of problems associated with environmental pollution by motor vehicles also includes fuel. In addition, diesel fuel produced in the Republic of Uzbekistan is not subject to deep desulfurization, which significantly increases smoke and emissions of nitrogen oxides. Environmental problems caused by the structural characteristics of engines and the fuel used are aggravated by existing operating conditions, a poorly developed network of toxicity diagnostics and engine regulation to achieve optimal operation. In addition, the condition of the roads and the organization of traffic do not allow maintaining operating modes of engines with minimal toxicity.

Solving environmental problems is a set of measures aimed at reducing the toxicity of vehicles. The implementation of many of them in civilized countries has significantly improved the environmental situation

Road transport as a source of environmental pollution

Studies conducted in various regions indicate significant air pollution in populated areas. A huge role in the formation of atmospheric air pollution is played by emissions of impurities formed during the combustion of fuel. At the same time, air pollution with lead, cadmium, benzo(a)pyrene and other chemicals becomes especially acute.

In a modern city, the undisputed leadership in the deterioration of the environmental situation lies with road transport. This is clearly reflected in the material presented here. Here are several reasons that cause the adverse impact of transport on the environment:

1) lack of clear environmental guidelines when making decisions in the field of development and ensuring the functioning of transport;

2) unsatisfactory environmental characteristics of manufactured transport equipment;

3) insufficient level of technical maintenance of the vehicle fleet;

4) insufficient development of roads and their poor quality, as well as shortcomings in the organization of transportation and vehicle traffic.

A number of researchers have shown a high correlation between the volume of traffic flow and the content of dust, organic substances and heavy metals in the air. It was noted that with a traffic intensity of 314 units/hour, the air dust content on the sidewalks exceeds the maximum permissible concentration. Moreover, the influence of vehicle emissions manifests itself at a distance of 1-2 km from the highway and extends to a height of 300 m or more.

When discussing the negative consequences of motorization, the most obvious problem is often touched upon - road traffic accidents (RTAs), which pose an immediate danger to people's lives.

Road transport makes a significant contribution to the constantly deteriorating environmental situation in many countries around the world. The intensity of atmospheric air pollution by exhaust gases (EG) of internal combustion engines (ICE) is associated with the corresponding widespread and widespread operation of road transport, especially in large industrial centers, where the volume and quantity of emitted pollutants have become a real environmental disaster. Thus, if in the early 70s the share of pollution introduced by motor vehicles into the atmospheric air was 13%, now this value has reached 50% (in industrial cities 60%) and continues to grow.

The list of sources of primary air pollution in the United States clearly shows the share of anthropogenic pollution.

At the same time, cars stand out among vehicles in terms of emissions. According to the data, in 1988, of the total volume of pollutant emissions into the Moscow air basin, which amounted to more than 1 million 130 thousand tons, 70% came from motor vehicles, including 633 thousand tons of carbon monoxide, 126 thousand tons of hydrocarbons, 42 thousand tons of nitrogen oxides (NOx). This means that for every resident of Moscow, more than 0.4 kg of toxic substances are emitted into the air with exhaust gases every day.

A similar situation regarding exhaust gas emissions from internal combustion engines is observed in developed countries of the world. For example, in Germany, the emission of harmful chemical compounds into the atmosphere from internal combustion engine exhaust per year is 156.7 million tons, and in total emissions, motor vehicles are the source of 70% CO, 52% NOx and 50% of all hydrocarbons. In Mexico City, 2 million cars consume 20 million liters of fuel per day and emit 10,300 tons of pollutants, including up to 300 tons of CO. The CO concentration in the air of Los Angeles is 88 μg/m 3 , Paris - 200, London - 300, Rome - 565 μg/m 3 . In our cities there is less gas pollution, however, there is a tendency for it to increase along with the vehicle fleet.

Thus, motor vehicles are a source of emissions into the atmosphere of a complex mixture of chemical compounds, the composition of which depends not only on the type of fuel, type of engine and operating conditions, but also on the effectiveness of emission control. The latter especially stimulates measures to reduce or neutralize toxic exhaust gas components.

Road transport is the most aggressive in relation to the environment compared to other modes of transport. It is a powerful source of chemical (supplies a huge amount of toxic substances into the environment), noise and mechanical pollution. It should be emphasized that with the increase in the vehicle fleet, the level of harmful effects of vehicles on the environment increases rapidly. Thus, if in the early 70s, hygienist scientists determined the share of pollution introduced into the atmosphere by road transport to be on average 13%, now it has already reached 50% and continues to grow. And for cities and industrial centers, the share of motor transport in the total volume of pollution is much higher and reaches 70% or more, which creates a serious environmental problem that accompanies urbanization.

There are several sources of toxic substances in cars, the main three of which are:

exhaust gases
crankcase gases
fuel fumes

Rice. Sources of toxic emissions

The largest share of chemical pollution of the environment by road transport comes from exhaust gases from internal combustion engines.

Theoretically, it is assumed that with complete combustion of fuel, carbon dioxide and water vapor are formed as a result of the interaction of carbon and hydrogen (included in the fuel) with oxygen in the air. The oxidation reactions have the form:

C+O2=CO2,
2H2+O2=2H2.

In practice, due to the physical and mechanical processes in the engine cylinders, the actual composition of the exhaust gases is very complex and includes more than 200 components, a significant part of which are toxic.

Table. Approximate composition of exhaust gases from automobile engines

Components	Dimension	Component concentration limits Gasoline, with spark. ignition Diesel
Components	Dimension	Gasoline	Diesel

Oxygen, O2
Water vapor, H2O			0,5…10,0
Carbon dioxide, CO2
Hydrocarbons, CH (total)
Carbon monoxide, CO
Nitric oxide, NOx
Aldehydes
Sulfur oxides (total)

Benz(a)pyrene
Lead compounds

Using the example of passenger cars without neutralization, the composition of engine exhaust gases can be presented in the form of a diagram.

Rice. Components of exhaust gases without neutralization

As can be seen from the table and figure, the composition of the exhaust gases of the types of engines under consideration differs significantly, primarily in the concentration of products of incomplete combustion - carbon monoxide, hydrocarbons, nitrogen oxides and soot.

Toxic components of exhaust gases include:

carbon monoxide
hydrocarbons
nitrogen oxides
sulfur oxides
aldehydes
benz(a)pyrene
lead compounds

The difference in the composition of the exhaust gases of gasoline and diesel engines is explained by the large excess air coefficient α (the ratio of the actual amount of air entering the engine cylinders to the amount of air theoretically required for the combustion of 1 kg of fuel) in diesel engines and better fuel atomization (fuel injection). In addition, in a gasoline carburetor engine, the mixture for different cylinders is not the same: for cylinders located closer to the carburetor it is rich, and for cylinders located further from it it is poorer, which is a disadvantage of gasoline carburetor engines. Part of the air-fuel mixture in carburetor engines enters the cylinders not in a vapor state, but in the form of a film, which also increases the content of toxic substances due to poor fuel combustion. This disadvantage is not typical for gasoline engines with fuel injection, since the fuel is supplied directly to the intake valves.

The reason for the formation of carbon monoxide and partially hydrocarbons is the incomplete combustion of carbon (the mass fraction of which in gasoline reaches 85%) due to an insufficient amount of oxygen. Therefore, the concentrations of carbon monoxide and hydrocarbons in the exhaust gases increase when the mixture is enriched (α 1, the probability of these transformations in the flame front is low and the exhaust gases contain less CO, but there are additional sources of its appearance in the cylinders:

low-temperature flame sections of the fuel ignition stage
drops of fuel entering the chamber at the late stages of injection and burning in a diffusion flame with a lack of oxygen
soot particles formed during the propagation of a turbulent flame along a heterogeneous charge, in which, with a general excess of oxygen, zones with oxygen deficiency can be created and reactions such as:

2C+O2 → 2СО.

Carbon dioxide CO2 is not toxic, but a harmful substance due to the recorded increase in its concentration in the planet’s atmosphere and its impact on climate change. The main share of CO formed in the combustion chamber is oxidized to CO2 without leaving the chamber, because the measured volume fraction of carbon dioxide in the exhaust gases is 10-15%, i.e. 300...450 times more than in atmospheric air. The greatest contribution to the formation of CO2 is made by the irreversible reaction:

CO + OH → CO2 + H

The oxidation of CO into CO2 occurs in the exhaust pipe, as well as in exhaust gas neutralizers, which are installed on modern cars for the forced oxidation of CO and unburned hydrocarbons to CO2 due to the need to meet toxicity standards.

Hydrocarbons

Hydrocarbons - numerous compounds of various types (for example, C6H6 or C8H18) consist of original or decayed fuel molecules, and their content increases not only when the mixture is enriched, but also when the mixture is lean (a > 1.15), which is explained by the increased amount of unreacted (unburned ) fuel due to excess air and misfires in individual cylinders. The formation of hydrocarbons also occurs due to the fact that the gas temperature at the walls of the combustion chamber is not high enough for fuel combustion, so here the flame is extinguished and complete combustion does not occur. Polycyclic aromatic hydrocarbons are the most toxic.

In diesel engines, light gaseous hydrocarbons are formed during the thermal decomposition of fuel in the flameout zone, in the core and in the leading edge of the flame, on the wall on the walls of the combustion chamber and as a result of secondary injection (boosting).

Solid particles include insoluble (solid carbon, metal oxides, silicon dioxide, sulfates, nitrates, asphalts, lead compounds) and soluble in organic solvent (resins, phenols, aldehydes, varnish, carbon deposits, heavy fractions contained in fuel and oil) substances.

Solid particles in the exhaust gases of supercharged diesel engines consist of 68...75% of insoluble substances, 25...32% of soluble substances.

Soot

Soot (solid carbon) is the main component of insoluble particulate matter. It is formed during volumetric pyrolysis (thermal decomposition of hydrocarbons in the gas or vapor phase with a lack of oxygen). The mechanism of soot formation includes several stages:

embryo formation
growth of nuclei to primary particles (hexagonal graphite plates)
increase in particle size (coagulation) to complex conglomerate formations, including 100... 150 carbon atoms
burnout

Soot release from the flame occurs at α = 0.33...0.70. In regulated engines with external mixture formation and spark ignition (petrol, gas), the likelihood of such zones appearing is insignificant. In diesel engines, local zones over-enriched with fuel are formed more often and the listed soot formation processes are fully realized. Therefore, soot emissions from exhaust gases from diesel engines are higher than from spark-ignition engines. The formation of soot depends on the properties of the fuel: the higher the C/H ratio in the fuel, the higher the soot yield.

In addition to soot, particulate matter contains sulfur and lead compounds. Nitrogen oxides NOx represent a set of the following compounds: N2O, NO, N2O3, NO2, N2O4 and N2O5. NO predominates in the exhaust gases of automobile engines (99% in gasoline engines and more than 90% in diesel engines). In the combustion chamber NO can form:

during high-temperature oxidation of air nitrogen (thermal NO)
as a result of low-temperature oxidation of nitrogen-containing fuel compounds (fuel NO)
due to the collision of hydrocarbon radicals with nitrogen molecules in the zone of combustion reactions in the presence of temperature pulsations (fast NO)

The combustion chambers are dominated by thermal NO, formed from molecular nitrogen during the combustion of a lean fuel-air mixture and a mixture close to stoichiometric, behind the flame front in the combustion products zone. Mainly during the combustion of lean and moderately rich mixtures (α > 0.8), reactions occur according to a chain mechanism:

O + N2 → NO + N
N + O2 → NO+O
N+OH → NO+H.

In rich mixtures (and< 0,8) осуществляются также реакции:

N2 + OH → NO + NH
NH + O → NO + OH.

In lean mixtures, the yield of NO is determined by the maximum temperature of the chain-thermal explosion (maximum temperature 2800...2900 ° K), i.e., the kinetics of formation. In rich mixtures, the NO yield ceases to depend on the maximum explosion temperature and is determined by the kinetics of decomposition and the NO content decreases. When burning lean mixtures, the formation of NO is significantly influenced by the unevenness of the temperature field in the zone of combustion products and the presence of water vapor, which is an inhibitor in the chain reaction of NOx oxidation.

The high intensity of the process of heating and then cooling the mixture of gases in an internal combustion engine cylinder leads to the formation of significantly nonequilibrium concentrations of reacting substances. Freezing (quenching) of the formed NO occurs at the level of maximum concentration, which is found in the exhaust gases due to a sharp slowdown in the rate of NO decomposition.

The main lead compounds in automobile exhaust gases are chlorides and bromides, as well as (in smaller quantities) oxides, sulfates, fluorides, phosphates and some of their intermediate compounds, which at temperatures below 370 ° C are in the form of aerosols or solid particles. About 50% of lead remains in the form of carbon deposits on engine parts and in the exhaust pipe; the remainder escapes into the atmosphere with exhaust gases.

Large amounts of lead compounds are released into the air when this metal is used as an anti-knock agent. Currently, lead compounds are not used as antiknock agents.

Sulfur oxides

Sulfur oxides are formed during the combustion of sulfur contained in fuel by a mechanism similar to the formation of CO.

The concentration of toxic components in exhaust gases is assessed in volume percent, parts per million by volume - ppm (ppm, 10,000 ppm = 1% by volume) and less often in milligrams per 1 liter of exhaust gases.

In addition to exhaust gases, sources of environmental pollution for cars with carburetor engines are crankcase gases (in the absence of closed crankcase ventilation, as well as fuel evaporation from the fuel system.

The pressure in the crankcase of a gasoline engine, with the exception of the intake stroke, is significantly less than in the cylinders, so part of the air-fuel mixture and exhaust gases breaks through the leaks of the cylinder-piston group from the combustion chamber into the crankcase. Here they mix with oil and fuel vapors washed off the cylinder walls of a cold engine. Crankcase gases dilute the oil, promote water condensation, aging and contamination of the oil, and increase its acidity.

In a diesel engine, during the compression stroke, clean air breaks into the crankcase, and during combustion and expansion, exhaust gases with concentrations of toxic substances proportional to their concentrations in the cylinder. The main toxic components in diesel crankcase gases are nitrogen oxides (45...80%) and aldehydes (up to 30%). The maximum toxicity of crankcase gases of diesel engines is 10 times lower than that of exhaust gases, so the share of crankcase gases in a diesel engine does not exceed 0.2...0.3% of the total emission of toxic substances. Taking this into account, forced crankcase ventilation is usually not used in automobile diesel engines.

The main sources of fuel evaporation are the fuel tank and the power system. Higher temperatures in the engine compartment, due to more loaded engine operating modes and the relative tightness of the vehicle's engine compartment, cause significant fuel evaporation from the fuel system when the hot engine is stopped. Given the large emission of hydrocarbon compounds as a result of fuel evaporation, all car manufacturers currently use special systems for their capture.

In addition to hydrocarbons coming from the vehicle power system, significant atmospheric pollution with volatile hydrocarbons of automobile fuel occurs when refueling vehicles (on average 1.4 g CH per 1 liter of fuel filled). Evaporation also causes physical changes in the gasolines themselves: due to changes in the fractional composition, their density increases, starting qualities deteriorate, and the octane number of gasolines of thermal cracking and direct distillation of oil decreases. In diesel cars, fuel evaporation is practically absent due to the low volatility of diesel fuel and the tightness of the diesel fuel system.

The level of air pollution is assessed by comparing the measured and maximum permissible concentrations (MPC). MAC values are established for various toxic substances for continuous, average daily and one-time exposure. The table shows the average daily MPC values for some toxic substances.

Table. Permissible concentrations of toxic substances

According to research, a passenger car with an average annual mileage of 15 thousand km “inhales” 4.35 tons of oxygen and “exhales” 3.25 tons of carbon dioxide, 0.8 tons of carbon monoxide, 0.2 tons of hydrocarbons, 0.04 tons of oxides nitrogen. Unlike industrial enterprises, the emissions of which are concentrated in a certain area, a car disperses the products of incomplete combustion of fuel throughout almost the entire territory of cities, directly in the ground layer of the atmosphere.

The share of pollution from cars in large cities reaches large values.

Table. Share of road transport in total air pollution in the world's largest cities, %

Toxic components of exhaust gases and evaporations from the fuel system have a negative effect on the human body. The degree of exposure depends on their concentrations in the atmosphere, the condition of the person and his individual characteristics.

Carbon monoxide

Carbon monoxide (CO) is a colorless, odorless gas. The density of CO is less than air, and therefore it can easily spread in the atmosphere. Entering the human body with inhaled air, CO reduces the function of oxygen supply, displacing oxygen from the blood. This is explained by the fact that the absorption of CO by the blood is 240 times higher than the absorption of oxygen. CO has a direct effect on tissue biochemical processes, leading to disruption of fat and carbohydrate metabolism, vitamin balance, etc. As a result of oxygen starvation, the toxic effect of CO is associated with a direct effect on the cells of the central nervous system. An increase in the concentration of carbon monoxide is also dangerous because, as a result of oxygen starvation of the body, attention is weakened, the reaction slows down, and the performance of drivers decreases, which affects road safety.

The nature of the toxic effects of CO can be traced from the diagram shown in the figure.

Rice. Diagram of the effects of CO on the human body:
1 – death; 2 – mortal danger; 3 – headache, nausea; 4 – onset of toxic action; 5 – beginning of noticeable action; 6 – inconspicuous action; T,h - exposure time

It follows from the diagram that even with a low concentration of CO in the air (up to 0.01%), prolonged exposure to it causes headaches and leads to decreased performance. A higher concentration of CO (0.02...0.033%) leads to the development of atherosclerosis, myocardial infarction and the development of chronic pulmonary diseases. Moreover, the effects of CO on people suffering from coronary insufficiency are especially harmful. At a CO concentration of about 1%, loss of consciousness occurs after just a few breaths. CO also has a negative effect on the human nervous system, causing fainting, as well as changes in color and light sensitivity of the eyes. Symptoms of CO poisoning include headache, palpitations, difficulty breathing and nausea. It should be noted that at relatively low concentrations in the atmosphere (up to 0.002%), CO associated with hemoglobin is gradually released and human blood is cleared of it by 50% every 3-4 hours.

Hydrocarbon compounds

Hydrocarbon compounds have not yet been sufficiently studied regarding their biological effects. However, experimental studies showed that polycyclic aromatic compounds caused cancer in animals. In the presence of certain atmospheric conditions (calm air, intense solar radiation, significant temperature inversion), hydrocarbons serve as starting products for the formation of extremely toxic products - photooxidants, which have a strong irritating and generally toxic effect on human organs, and form photochemical smog. Particularly dangerous from the group of hydrocarbons are carcinogenic substances. The most studied is the polynuclear aromatic hydrocarbon benzo(a)pyrene, also known as 3,4 benzo(a)pyrene, a substance that appears as yellow crystals. It has been established that malignant tumors appear in places of direct contact of carcinogenic substances with tissue. If carcinogenic substances deposited on dust particles enter the lungs through the respiratory tract, they are retained in the body. Toxic hydrocarbons are also gasoline vapors entering the atmosphere from the fuel system, and crankcase gases escaping through ventilation devices and leaks in the connections of individual engine components and systems.

Nitric oxide

Nitric oxide is a colorless gas, and nitrogen dioxide is a red-brown gas with a characteristic odor. When nitrogen oxides enter the human body, they combine with water. At the same time, they form compounds of nitric and nitrous acids in the respiratory tract, irritating the mucous membranes of the eyes, nose and mouth. Nitrogen oxides are involved in processes leading to the formation of smog. The danger of their influence lies in the fact that poisoning of the body does not appear immediately, but gradually, and there are no neutralizing agents.

Soot

When soot enters the human body, it causes negative consequences in the respiratory organs. If relatively large soot particles with a size of 2...10 microns are easily removed from the body, then small ones with a size of 0.5...2 microns are retained in the lungs and respiratory tract, causing allergies. Like any aerosol, soot pollutes the air, impairs visibility on the roads, but, most importantly, heavy aromatic hydrocarbons, including benzo(a)pyrene, are adsorbed on it.

Sulfur dioxide SO2

Sulfur dioxide SO2 is a colorless gas with a pungent odor. The irritating effect on the upper respiratory tract is explained by the absorption of SO2 by the moist surface of the mucous membranes and the formation of acids in them. It disrupts protein metabolism and enzymatic processes, causing eye irritation and coughing.

Carbon dioxide CO2

Carbon dioxide CO2 (carbon dioxide) does not have a toxic effect on the human body. It is well absorbed by plants releasing oxygen. But when there is a significant amount of carbon dioxide in the earth’s atmosphere, absorbing the sun’s rays, a greenhouse effect is created, leading to the so-called “thermal pollution”. As a result of this phenomenon, the air temperature in the lower layers of the atmosphere increases, warming occurs, and various climatic anomalies are observed. In addition, an increase in CO2 content in the atmosphere contributes to the formation of “ozone” holes. With a decrease in ozone concentration in the earth's atmosphere, the negative impact of hard ultraviolet radiation on the human body increases.

The car is also a source of air pollution due to dust. While driving, especially when braking, rubber dust is formed as a result of friction of tires on the road surface, which is constantly present in the air on highways with heavy traffic. But tires are not the only source of dust. Solid particles in the form of dust are emitted with exhaust gases, brought into the city in the form of dirt on car bodies, formed from abrasion of the road surface, lifted into the air by vortex flows that arise when the car is moving, etc. Dust has a negative impact on human health and has a detrimental effect on the plant world.

In urban environments, the car is a source of warming the surrounding air. If 100 thousand cars are moving in a city at the same time, then this is equal to the effect produced by 1 million liters of hot water. Exhaust gases from cars, containing warm water vapor, contribute to climate change in the city. Higher steam temperatures increase heat transfer by the moving medium (thermal convection), resulting in increased precipitation over the city. The influence of the city on the amount of precipitation is especially clearly visible from its natural increase, which occurs in parallel with the growth of the city. Over a ten-year observation period in Moscow, for example, 668 mm of precipitation fell per year, in its environs - 572 mm, in Chicago - 841 and 500 mm, respectively.

Side effects of human activity include acid rain - combustion products dissolved in atmospheric moisture - nitrogen and sulfur oxides. This mainly applies to industrial enterprises whose emissions are discharged high above the surface level and which contain a lot of sulfur oxides. The harmful effects of acid rain include the destruction of vegetation and accelerated corrosion of metal structures. An important factor here is that acid rain, together with the movement of atmospheric air masses, can travel distances of hundreds and thousands of kilometers, crossing state borders. Periodicals contain reports of acid rain falling in different European countries, the USA, Canada, and even seen in protected areas such as the Amazon.

Temperature inversions, a special state of the atmosphere in which the air temperature increases with altitude rather than decreases, have an adverse effect on the environment. Surface temperature inversions are the result of intense radiation of heat from the soil surface, as a result of which both the surface and adjacent layers of air cool. This state of the atmosphere prevents the development of vertical air movements, so water vapor, dust, and gaseous substances accumulate in the lower layers, contributing to the formation of layers of haze and fog, including smog.

The widespread use of salt to combat ice on roads leads to a reduction in the service life of cars and causes unexpected changes in roadside flora. Thus, in England, the appearance of plants characteristic of sea coasts along the roads was noted.

A car is a strong polluter of water bodies and underground water sources. It has been determined that 1 liter of oil can make several thousand liters of water undrinkable.

A large contribution to environmental pollution is made by the processes of maintenance and repair of rolling stock, which require energy costs and are associated with high water consumption, the release of pollutants into the atmosphere, and the generation of waste, including toxic ones.

When performing vehicle maintenance, units, zones of periodic and operational forms of maintenance are involved. Repair work is carried out at production sites. Technological equipment, machine tools, mechanization equipment and boiler plants used in maintenance and repair processes are stationary sources of pollutants.

Table. Sources of release and composition of harmful substances in production processes at operational and repair enterprises of transport

Name of zone, section, department	Manufacturing process	Equipment used	Released harmful substances
Rolling stock washing area	Washing external surfaces	Mechanical washing (washing machines), hose washing	Dust, alkalis, synthetic surfactants, petroleum products, soluble acids, phenols
Maintenance areas, diagnostic area	Maintenance	Lifting and transporting devices, inspection ditches, stands, equipment for changing lubricants, components, exhaust ventilation system	Carbon monoxide, hydrocarbons, nitrogen oxides, oil mist, soot, dust
Mechanical mechanics department	Metalworking, boring, drilling, planing work	Lathe, vertical drilling, planing, milling, grinding and other machines	Abrasive dust, metal shavings, oil mist, emulsions
Elsktrotechnical department	Grinding, insulating, winding works	Grinding machine, electrotin baths, soldering equipment, test benches	Abrasive and asbestos dust, rosin, acid fumes, tertiary
Battery section	Assembly, disassembly and charging work	Washing and cleaning baths, welding equipment, shelving, exhaust ventilation system	Flushing solutions, acid vapors, electrolyte, sludge, washing aerosols
Fuel equipment department	Adjustment and repair work on fuel equipment	Test stands, special equipment, ventilation system	Gasoline, kerosene, diesel fuel. acetone, benzene, rags
Forging and spring department	Forging, hardening, tempering of metal products	Forge, thermal baths, exhaust ventilation system	Coal dust, soot, oxides of carbon, nitrogen, sulfur, contaminated wastewater
Mednitsko-Zhestyanitsky branch	Cutting, soldering, straightening, molding according to templates	Metal shears, soldering equipment, templates, ventilation system	Acid fumes, tertiary, emery and metal dust and waste
Welding department	Electric arc and gas welding	Equipment for arc welding, acetylene - oxygen generator, exhaust ventilation system	Mineral dust, welding aerosol, manganese, nitrogen, chromium oxides, hydrogen chloride, fluorides
Valve department	Glass cutting, repair of doors, floors, seats, interior decoration	Electric and hand tools, welding equipment	Dust, welding aerosol, wood and metal shavings, metal and plastic waste
Wallpaper department	Repair and replacement of worn, damaged seats, shelves, armchairs, sofas	Sewing machines, cutting tables, knives for cutting and cutting foam rubber	Mineral and organic dust, waste fabrics and synthetic materials
Tire fitting and repair area	Disassembly and assembly of tires, repair of tires and tubes, balancing work	Stands for disassembling and assembling tires, equipment for vulcanization, machines for dynamic and static balancing	Mineral and rubber dust, sulfur dioxide, gasoline vapors
Plot paint and varnish coatings	Removing old paint, degreasing, applying paint and varnish coatings	Equipment for pneumatic or airless spraying, baths, drying chambers, ventilation system	Mineral and organic dust, solvent vapors and paint sols, contaminated wastewater
Engine running-in area (for repair companies)	Cold and hot engine running-in	Run-in stand, exhaust ventilation system	Oxides of carbon, nitrogen, hydrocarbons, soot, sulfur dioxide
Parking lots and storage areas for rolling stock	Moving rolling stock units, waiting	Equipped open or closed storage area	Same

Wastewater

When operating vehicles, wastewater is generated. The composition and quantity of these waters are different. Wastewater is returned back to the environment, mainly to objects of the hydrosphere (river, canal, lake, reservoir) and land (fields, reservoirs, underground horizons, etc.). Depending on the type of production, wastewater at transport enterprises can be:

car wash wastewater
oily wastewater from production areas (cleaning solutions)
wastewater containing heavy metals, acids, alkalis
waste water containing paint, solvents

Wastewater from car washes accounts for 80 to 85% of the volume of industrial wastewater from motor transport organizations. The main pollutants are suspended substances and petroleum products. Their content depends on the type of vehicle, the nature of the road surface, weather conditions, the nature of the cargo being transported, etc.

Wastewater from the washing of units, components and parts (used washing solutions) is distinguished by the presence in it of a significant amount of petroleum products, suspended solids, alkaline components and surfactants.

Wastewater containing heavy metals (chromium, copper, nickel, zinc), acids and alkalis is most typical for car repair industries using galvanic processes. They are formed during the preparation of electrolytes, surface preparation (electrochemical degreasing, etching), electroplating and washing of parts.

During the painting process (using pneumatic spraying), 40% of the paint and varnish materials enter the air of the working area. When these operations are carried out in painting booths equipped with hydrofilters, 90% of this amount settles on the elements of the hydrofilters themselves, 10% is carried away with water. Thus, up to 4% of spent paint and varnish materials end up in wastewater from painting areas.

The main direction in the field of reducing pollution of water bodies, ground and underground waters by industrial wastewater is the creation of recycling water supply systems for production.

Repair work is also accompanied by soil contamination and the accumulation of metal, plastic and rubber waste near production areas and departments.

During the construction and repair of communication routes, as well as industrial and household facilities of transport enterprises, water, soil, fertile soils, subsoil mineral resources are removed from ecosystems, natural landscapes are destroyed, and interference in the animal and plant world occurs.

Noise

Along with other modes of transport, industrial equipment, and household appliances, the car is a source of artificial background noise in the city, which, as a rule, has a negative impact on humans. It should be noted that even without noise, if it does not exceed acceptable limits, a person feels discomfort. It is no coincidence that Arctic researchers have repeatedly written about “white silence”, which has a depressing effect on humans, while the “noise design” of nature has a positive effect on the psyche. However, artificial noise, especially loud noise, has a negative effect on the nervous system. The population of modern cities faces a serious problem of dealing with noise, since loud noise not only leads to hearing loss, but also causes mental disorders. The danger of noise exposure is aggravated by the human body’s ability to accumulate acoustic stimuli. Under the influence of noise of a certain intensity, changes occur in blood circulation, the functioning of the heart and endocrine glands, and muscle endurance decreases. Statistics show that the percentage of neuropsychiatric diseases is higher among people working in conditions of high noise levels. The reaction to noise is often expressed in increased excitability and irritability, covering the entire sphere of sensitive perceptions. People exposed to constant noise often find it difficult to communicate.

Noise has a harmful effect on the visual and vestibular analyzers, reduces the stability of clear vision and reflex activity. The sensitivity of twilight vision weakens, and the sensitivity of daytime vision to orange-red rays decreases. In this sense, noise is an indirect killer of many people on the world's highways. This applies both to vehicle drivers working in conditions of intense noise and vibration, and to residents of large cities with high noise levels.

Noise combined with vibration is especially harmful. If short-term vibration tones the body, then constant vibration causes the so-called vibration disease, i.e. a whole range of disorders in the body. The driver's visual acuity decreases, the field of vision narrows, color perception or the ability to estimate the distance to an oncoming car may change. These violations, of course, are individual, but for a professional driver they are always undesirable.

Infrasound is also dangerous, i.e. sound with a frequency less than 17 Hz. This individual and silent enemy causes reactions that are contraindicated for a person behind the wheel. The effect of infrasound on the body causes drowsiness, deterioration of visual acuity and a slow reaction to danger.

Of the sources of noise and vibration in a car (gearbox, rear axle, driveshaft, body, cabin, suspension, as well as wheels and tires), the main one is the engine with its intake and exhaust, cooling and power systems.

Rice. Analysis of truck noise sources:
1 – total noise; 2 – engine; 3 – exhaust system; 4 – fan; 5 – air intake; 6 – rest

However, when the vehicle speed is more than 50 km/h, the predominant noise is generated by the vehicle tires, which increases in proportion to the vehicle speed.

Rice. Dependence of vehicle noise on driving speed:
1 – range of noise dissipation due to different combinations of road surfaces and tires

The combined effect of all sources of acoustic radiation leads to the high noise levels that characterize a modern car. These levels also depend on other reasons:

road surface condition
speed and direction changes
changes in engine speed
loads
etc.