Atmospheric pollution by motor vehicles. Research work
Plan
Introduction
Main part
Conclusion
Sources of information
Introduction
Road transport is one of the most important components of social and economic development, absorbing a significant amount of resources and having a serious impact on the environment. The rapid growth in the number of vehicles on the roads has led to a significant complication of the environmental situation, especially in large cities.
Nature is an integral system with many balanced connections.
Violation of these bonds leads to a change in the cycles of substances and energy established in nature.
The increased technogenic impact of road transport on the natural environment has given rise to a number of environmental problems. The most acute are associated with the state of the atmosphere, hydrosphere and lithosphere. Some "changes", such as air or water pollution, can directly affect the health and functioning of an organism. Others are fraught with indirect effects. Pollution entering the atmosphere returns to Earth with precipitation and enters water bodies and soil.
This paper considers the environmental problems of motor transport and its infrastructure associated with the negative impact on air, water, soil and public health.
1. Main body
By the end of the 20th century, a modern transport complex was created in the Russian Federation and, on the whole, successfully operates, ensuring its territorial integrity and national security. Road transport plays a key role in its development: according to the Ministry of Transport of the Russian Federation, the contribution of road transport to the transportation of goods is 75-77%, passengers (excluding personal cars) - 53-55%. Why is obvious: motor transport has such important advantages as mobility, the ability to deliver goods and passengers door-to-door and just-in-time.
But along with the benefits that a developed motor transport complex provides to society, its progress is accompanied, unfortunately, by a negative impact on the environment and humans. Therefore, scientists and specialists around the world are intensively looking for ways and means to reduce the negative consequences of motorization.
Many Russian scientists refer to the sources of environmental pollution by the motor transport complex of a large city: cars in motion; production and technical base - parking lots, motor transport enterprises, garage-building cooperatives, car service stations, gas stations, as well as roads and engineering structures (bridges, overpasses), i.e., in fact, only technical objects. According to scientists, the harmful impact of ATC on the environment lies in its negative change as a result of toxic components of exhaust gases, wear products of parts, roadways, waste from production and operational activities generated during movement, in loading processes - unloading, refueling, washing, storage, maintenance and repair of vehicles. At the same time, the federal law "On Environmental Protection", which was prepared, of course, not without the participation of scientists and specialists, refers to negative environmental impacts as follows: emissions of pollutants and other substances into the atmospheric air; discharges of pollutants, other substances and microorganisms into surface, underground water bodies and catchment areas; pollution of bowels, soils; disposal of production and consumption waste; increased noise, the influence of thermal, electromagnetic, ionizing and other types of physical influences. That is, the law considers the problem much broader, however, it does not affect the aspects of the interaction of some elements of the motor transport complex with the environment.
The first of these elements is a continuously growing car park: at present, more than 800 million cars are in operation in the world, over 100 million in Europe, and 33.4 million in Russia. Of these, 83-85% are cars and 15-17 % - trucks and buses. The annual production of passenger cars in the world over the past 50 years has increased by 5.5 times and, for example, in 2002 amounted to 60 million units, including 16.9 million in the EU countries. At the same time, the growth in production of ATS continues . As a result, they annually consume 2.1 billion tons of fuel and emit ~700 million tons of harmful substances into the atmosphere, i.e. 1.3 tons/year per one average car. Therefore, the share of road transport in the total air pollution in developed countries reached an average of 45-50%, Russia - 40%, cities - 50-60%, megacities - up to 85-90%.
Consider the metabolism of an "average" passenger car with a carburetor engine with a fuel consumption in the mixed driving mode of 8 liters (6 kg) per 100 km. With optimal engine operation, burning 1 kg of gasoline is accompanied by the consumption of 13.5 kg of air and the emission of 14.5 kg of waste substances. Their composition is shown in Table. 1. The corresponding diesel engine emission is slightly less. In general, up to 200 individual substances are registered in the exhaust of a modern car. The total mass of pollutants - an average of about 270 g per 1 kg of gasoline burned - gives, in terms of the entire volume of fuel consumed by passenger cars in the world, about 340 million tons. A similar calculation for all road transport (plus trucks, buses) will increase this figure by at least up to 400 million tons. It should also be borne in mind that in the actual practice of operating vehicles, spills and leaks of fuel and oils, the formation of metal, rubber and asphalt dust, and harmful aerosols are very significant.
Table 1 The composition of the exhaust gases of the car,% by volume
ComponentsEnginesCarburetorDieselN 272-7574-76O 20.3 - 0.81.5-3.6N 2О3-80.8-4СО 210-14.56-10СО0.5 - 1.30.1 - 0.5NO x 0.1 - 0.80.01 - 0.5C x H y 0.2 - 0.30.02 - 0.5 Aldehydes 0-0.20 - 0.01 Particles, g/m ³ 0.1 - 0.40.1 - 1.5Benzopyrene, µg/m³ 10-20 to 10
Air pollutants directly emitted by cars, such as carbon monoxide, nitrogen oxides, hydrocarbons or lead, mainly accumulate in the vicinity of pollution sources, i.e. along highways, streets, in tunnels, at intersections, etc. In this way, localgeoecological impacts of transport.
Some pollutants are transported over long distances from the place of emission, are transformed in the process of transport and cause regionalgeoecological impacts. The most common process in this category is acidification - acidification of the environment.
Carbon dioxide and other greenhouse gases spread throughout the atmosphere, causing globalgeoecological impacts.
Almost 1/4 of the entire industrial potential of the developed countries of the world, almost all industries are involved in the production of automobiles. The creation of a 1-ton car is accompanied by the formation of 15 to 18 tons of solid and 7-8 tons of liquid waste in all supporting industries.
Road transport is one of the main sources of noise in the city, the traffic intensity of which is constantly growing. The highest noise levels of 90-95 dB are observed on the main streets of cities with an average traffic intensity of 2-3 thousand or more vehicles per hour.
The high values of noise characteristics of highways cause the current sanitary standards to be exceeded by 20-25 dBA (SN 2.2.4 / 2.1.8.562-96) in areas adjacent to residential buildings located in close proximity to highways.
In residential areas remote from highways or "protected" by planting trees, noise levels are significantly lower, exceeding the standards is no more than 5-8 dBA.
Exceeding the permissible noise levels near motorways are observed during the daytime, affecting the night hours from 23.00 to 01.00.
The exception is the courtyards of residential buildings located out of direct line of sight of highways or at a distance (70-100 meters from the highway), as well as areas protected by the first echelon of buildings or other noise-protective structures.
The level of street noise is determined by the intensity, speed and nature (composition) of the traffic flow. In addition, it depends on planning decisions (longitudinal and transverse profile of streets, building height and density) and such landscaping elements as roadway coverage and the presence of green spaces. Each of these factors can change the level of traffic noise up to 10 dB.
In an industrial city, the percentage of freight transport on highways is usually high. An increase in the general traffic flow of trucks, especially heavy trucks with diesel engines, leads to an increase in noise levels. In general, trucks and cars create a heavy noise regime in the cities.
The noise that occurs on the roadway of the highway extends not only to the territory adjacent to the highway, but also deep into residential buildings. So, in the zone of the strongest noise impact there are parts of blocks and microdistricts located along highways of general city significance (equivalent noise levels from 67.4 to 76.8 dB). Noise levels measured in living rooms with open windows oriented to the indicated highways are only 10-15 dB lower.
The acoustic characteristic of the traffic flow is determined by the indicators of the noise level of motor vehicles. The noise produced by individual transport crews depends on many factors: engine power and operation mode, technical condition of the crew, quality of the road surface, speed. In addition, the noise level, as well as the efficiency of the operation of the car, depends on the qualifications of the driver. The noise from the engine increases sharply at the time of its start and warming up (up to 10 dB). The movement of the car at the first speed (up to 40 km / h) causes excessive fuel consumption, while the engine noise is 2 times higher than the noise generated by it at the second speed. Significant noise causes sudden braking of the car when driving at high speed. Noise is noticeably reduced if the driving speed is dampened by engine braking until the foot brake is applied.
Recently, the average level of noise produced by transport has increased by 12-14 dB.
The second element of the ATK is the production and technical base (PTB), which includes: cargo terminals; bus stations; gas stations; parking lots; garage-building cooperatives; car washes; motor transport enterprises; car service stations and other technical facilities intended for loading and unloading operations, passenger transportation, refueling, storage, washing, maintenance and repair of vehicles.
These facilities also have a negative impact on the environment. Thus, in private auto repair shops there are no containers for collecting waste contaminated with oil products (filters, rubber products, oily rags, etc.), the issue of disposal of used motor oils and other technical fluids has not been resolved, as a result of which unorganized landfills are formed in the city.
Most car washes operate without circulating water supply systems, so a significant part of liquid waste contaminated with oil products is taken to the landfill.
Various types of sites and wastelands are adapted for parking lots. However, the construction and operation of car parks is often accompanied by a violation of environmental requirements. So the territory of some parking lots does not have a hard surface, there are no storm sewer systems, the adjacent territory is not landscaped.
The third element of the ATC is motor roads, which are one of the most important objects of the transport and communication infrastructure.
The transport network provides, along with advantages, also a significant negative impact on the environment. Moreover, the impact is multifaceted: alienation of land, pollution of roadside areas (lead, heavy metals, ATC waste), carcinogenic emissions from asphalt concrete plants and road construction machines, poor quality of roads and the state of their surface, which are the cause of numerous accidents, etc. And here too Russia is also in the lead.
So, if we take 2002, then in the world the length of paved roads was 12 million km, which is 1.36 times more than the total length (8.8 million km) of all other types of transport network (overhead lines - 5 .6 million km, railways - 1.5 million, main pipelines - about 1.1 million, inland waterways - more than 0.6 million km). The length of motor roads of the Russian Federation was equal to 910-920 thousand km, of which only 750 thousand km were paved. Moreover, most of them (more than 80%) - the second, third and fourth categories, more than a third needed reconstruction. According to experts, the country's economic and social needs require an increase in the road network to 1,500,000 km, that is, 600,000 km more. It is easy to calculate that at the current average rate of construction (~6 thousand km per year), this problem can be solved in at least 100 years. As a result, now 29,000 cities and towns with a population of more than 10 million people do not have paved roads and year-round communication with the outside world, and the low technical level of existing roads causes an increase in the cost of transportation by 1.5 times, fuel consumption by 30% in relation to similar indicators of developed foreign countries.
The situation is no better in cities: their road transport infrastructure actually corresponds to the level of 60-100 cars per 1,000 inhabitants, while the current level has already exceeded 200 cars per 1,000 inhabitants. The consequence of this situation is well known: deterioration in traffic conditions, congestion, increased fuel consumption, unfavorable environmental conditions and an increase in the number of accidents (more than 70% of them occur in cities and towns).
The rapid increase in the number of motor vehicles, the insufficient number of modern roads and PTB is inevitably accompanied by an increase in the number of accidents and the number of people killed and injured in accidents. According to the UN (1998), about 300 thousand people die every year in car accidents in the world and ~ 10 million are injured, and the US National Traffic Safety Council notes that the damage from road accidents in this country in the same 1998 amounted to 50 billion dollars a year. In Germany, annual losses from motor vehicle accidents have reached 14-15 billion marks. And I must say that over the past eight years, the situation has not changed much. For example, in our country in 2004 there were over 208 thousand traffic accidents, in which 34.5 thousand people died. That is, compared with 1997, the number of deaths increased by 28%. Moreover, more than a quarter of them are people of the most able-bodied age (26-40 years). Worse, in Russia the number of accidents per 1 thousand cars is 7-10 times higher than in Germany, the USA, France, Japan and other economically developed countries. Over the past four years, car accidents have caused damage to the Russian economy, which amounted to 2.5% of the country's GDP (for example, in 2004 alone, the damage was equal to 369 billion rubles, including 228 billion rubles as a result of death and injury of people .).
Thus, with the growth of the vehicle fleet, environmental and road safety, the main components of the operational safety of the ATK, decreases. Therefore, they cannot be considered separately, as many scientists do. ecological car fuel carburetor
It follows from the life cycle theory that each of the above technical elements of the motor transport complex (car, production and technical base, road) goes through successive (interrelated) stages of the production system, from the acquisition of raw materials or the development of natural resources to the disposal of products. But the main thing that you need to pay special attention to is the three main stages of the functioning of this system: design (construction), manufacture and practical operation of the automatic telephone exchange.
As for the trend of the prospective development of new motor transport facilities in the Russian Federation at the stages of design and manufacture, they have been studied in sufficient detail by many scientists and are set out in the relevant state documents - the "Concept for the Development of the Russian Automotive Industry" until 2010; target program "Improving road safety in 2006-2012"; subprogram "Roads" of the federal target program "Modernization of the transport system of Russia" (2002-2010), etc. Russia's integration into the European and world economic communities, expanding international transportation have significantly increased the requirements for environmental and road safety, economic and other indicators while certification of new domestic automotive equipment to ensure their gradual approximation to European standards. Moreover, the EU countries have adopted more stringent environmental standards of the UNECE ("Euro-2" - "Euro-4"). However, neither these standards, nor the more lenient Rules No. 19 "Carrying out work in the system of certification of mechanical vehicles and trailers" do not comply with the majority of new and already operated Russian vehicles.
Conclusion
Thus, the negative impact of motor transport is that:
ü automobiles pollute the environment, especially air, but also water, and cause significant noise and vibration;
ü a lot of land resources are consumed for transport infrastructure - roads and related stations, parking lots, gas stations, car washes, etc. The transport infrastructure creates man-made landscapes of considerable area;
ü a significant amount of natural resources is spent on the production of cars and the construction of elements of transport infrastructure;
ü all types of transport pose a serious danger to the life, health and property of people.
Due to the significant impacts of transport at the local, regional and global levels, it is necessary to strive to implement the following directions of a coordinated global strategy as components of sustainable development:
The consumption of fossil fuels for transport must be reduced.
Worldwide air emission standards for all modes of transport should be set based on advanced technology.
Each country should develop and implement an emission control program for all sources and modes of transport.
Improve and develop a reliable and accessible public transport system.
When planning the development of transport systems, use a systematic approach aimed at a comprehensive solution of environmental problems. Eliminate the causes, not the consequences of geo-environmental problems in transport.
The overall goal in transport system management is to find the optimal balance between meeting the needs of society and reducing environmental pollution. Management strategies will depend on local situations and therefore will be different for specific countries, regions and cities.
One of the indispensable conditions for reducing the harmful effects of transport on the environment is to maintain it in a technically sound condition.
Air pollution in cities, large towns with heavy traffic forces us to look for an alternative to a car with an internal combustion engine. The battery electric vehicle is promising, although there are many questions and unresolved problems.
It is important to create non-polluting public transport: this includes the subway, high-speed railways, magnetic levitation vehicles, etc.
Sources of information
1. Akimova T.A., Kuzmin A.P., Khaskin V.V. Ecology. Nature - Man - Technique: Textbook for high schools. - M.: UNITI-DANA, 2001.
2. The impact of vehicles on the environment // http://ecology.volgadmin.ru/ecology/htmls/monitor/Air/air3.htm
Golubev G.N. Geoecology. Textbook for students of higher educational institutions. -M.: Publishing house GEOS, 1999.
Stepanovskikh A.S. Ecology: Textbook for universities. - M.: UNITI-DANA, 2001. - 703 p.
Noise impact // http://www.moseco.ru/ru/showArticle/atlID/38?PHPSESSID=299043b
Yasenkov E.P. Elements of the motor transport complex and their impact on the environment // "Automotive Industry", 2007, No. 8 //
http://transpenv.org.ru/people.html
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I decided to choose the topic "The role of the car in environmental pollution" in order to once again emphasize and give an opportunity to think about a problem that should worry every resident of a city where there is a car.
Mobile sources include cars and vehicles moving on land, water and air. In large cities, the main sources of air pollution are transport. The exhaust gases of engines contain a complex mixture of more than two hundred components, among which there are many carcinogens. Ground vehicles are mechanisms moving on highways and railways, as well as construction, agricultural and military equipment. In accordance with the differences in the amounts and types of pollutants emitted, it is useful to consider separately internal combustion engines (especially two- and four-stroke engines) and diesel engines, and similarly steam and diesel locomotives. Table 3 shows emissions from mobile sources.
Table #3
Main types of pollutant emissions from mobile sources
|
ENGINE'S TYPE |
MAIN TYPES OF POLLUTION | ||
|
Four-stroke internal combustion engine |
Hydrocarbons, carbon monoxide, nitrogen oxides |
Cars, buses, planes, motorcycles |
|
|
Two-stroke internal combustion engine |
Gasoline (with added oil) |
Hydrocarbons, carbon monoxide, nitric oxide, solids |
Motorcycle auxiliary motors |
|
Buses, tractors, cars, trains |
|||
|
gas turbine |
Nitrogen oxides, solids |
Planes, ships, trains |
|
|
steam boiler |
Coal, oil |
Nitrogen oxides, sulfur dioxide, solids |
Ships, locomotives |
During the operation of mobile vehicles, harmful substances enter the air with exhaust gases, fumes from fuel systems and during refueling, as well as with crankcase gases. Carbon monoxide emissions are significantly affected by the road topography and the mode of movement of the vehicle. So, for example, during acceleration and braking in the exhaust gases, the content of carbon monoxide increases by almost 8 times. The minimum amount of carbon monoxide is released at a uniform vehicle speed of 60 km/h.
Table No. 4 shows the concentration values of the main impurities of the carburetor engine for various modes of its operation.
Table No. 4
The concentration of substances depending on the mode of operation of the carburetor engine
|
Engine operating mode |
Carbon monoxide, % by volume |
Hydrocarbons, mg/l |
Nitrogen oxides, mg/l |
|
Idling | |||
|
Forced idle | |||
|
Medium loads | |||
|
Full loads |
Emissions of nitrogen oxides are maximum at an air-fuel ratio of 16:1. Thus, the values of emissions of harmful substances in the exhaust gases of motor vehicles depend on a number of factors: the ratio in the mixture of air and fuel, the modes of movement of vehicles, the relief and quality of roads, the technical condition of vehicles, etc. The composition and volumes of emissions also depend on the type of engine. Table No. 5 shows emissions of a number of harmful substances from carburetor and diesel engines.
Table number 5
Emissions (% by volume) of substances during the operation of diesel and carburetor engines
|
SUBSTANCE |
ENGINE |
|
|
carbureted |
Diesel |
|
|
carbon monoxide | ||
|
Nitrogen oxide | ||
|
hydrocarbons | ||
|
Benz(a)pyrene |
Up to 20 µg/m 3 |
Up to 10 µg/m 3 |
As can be seen from Table 5, emissions of major pollutants are significantly lower in diesel engines. Therefore, they are considered to be more environmentally friendly. However, diesel engines are characterized by increased emissions of soot, which is formed due to fuel overload. Soot is saturated with carcinogenic hydrocarbons and trace elements; their emissions into the atmosphere are unacceptable.
Due to the fact that the exhaust gases of vehicles enter the lower atmosphere, and the process of their dispersion differs significantly from the process of dispersion of high stationary sources, harmful substances are practically in the human breathing zone. Therefore, road transport should be classified as the most dangerous source of air pollution near highways.
According to the formula for the average specific emission (emission factor)
Total annual emission of pollutants
sum of annual transport indicators
Table 6 shows these values for automotive emissions
Table No. 6 Average specific emissions (emission factors) of vehicles
|
TYPE OF POLLUTANT |
AVERAGE SPECIFIC EMISSION (AT AN AVERAGE TRANSPORT SPEED OF 31.7 KM/H) |
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|
In hour |
per kilometer |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
carbon monoxide | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Unburned hydrocarbons | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
nitrogen oxides | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Total amount of exhaust gases (at 0 0 С) |
0.914 m 3 /km |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Average fuel consumption |
All vehicles with autonomous prime movers pollute the atmosphere to some extent with chemical compounds contained in exhaust gases. On average, the contribution of certain types of vehicles to air pollution is as follows: Automobile - 85%, Sea and river - 5.3%, Air - 3.7%, Railway - 3.5%, Agricultural - 2.5%. Along with environmental pollution by harmful emissions, one should note the physical impact on the atmosphere in the form of the formation of anthropogenic physical fields (increased noise, infrasound, electromagnetic radiation). Of these factors, noise is the most influential. Transport is the main source of acoustic pollution of the environment. In large cities, the noise level reaches 70 ... 75 dBA, which is several times higher than the permissible norms. The main source of acoustic pollution of the environment is road transport: its contribution to acoustic pollution in cities ranges from 75 to 90%. The car negatively affects almost all components of the biosphere: the atmosphere, water, land resources, the lithosphere and humans. Exhausts from motor vehicles spread along the city streets along the roads, causing harmful effects on pedestrians, residents of nearby houses and vegetation. It was revealed that zones with exceeding the MPC for nitrogen dioxide and carbon monoxide cover up to 90% of the urban area. The car is the most active consumer of air oxygen. If a person consumes up to 20 kg (15.5 m3) of air per day and up to 7.3 tons per year, then a modern car consumes about 12 m3 of air, or, in oxygen equivalent, about 250 liters of oxygen to burn 1 kg of gasoline. Thus, in large metropolitan areas, road transport absorbs ten times more oxygen than the weight of their population. Previous studies have shown that in calm, calm weather and low atmospheric pressure on busy highways, the volume concentration of oxygen in the air often drops to 15%. It is known that at an oxygen concentration in the air 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. When fuel is burned in engine cylinders, non-toxic (water vapor, carbon dioxide) and toxic substances are formed. The latter are products of combustion or side reactions occurring at high temperatures. These include carbon monoxide CO, hydrocarbons CmHn, oxides of nitrogen (NO and NO2) commonly referred to as NOX. In addition to the listed substances, lead compounds, carcinogens (benzo (a) pyrene), soot and aldehydes, emitted during the operation of engines, have a harmful effect on the human body. | Municipal budgetary educational institution Secondary school No. 8 of Poronaysk Compiled by: Gargaeva Daria MBOU secondary school No. 8 of Poronaysk Scientific adviser: Chebanova Yulia Gennadievna MBOU secondary school No. 8 of Poronaysk Poronaysk, 2012 The car is the main factor in environmental pollution. Content
3.2. electric car 3.3. Gas instead of petrol Conclusion Bibliography Application Introduction The beginning of the second half of the 20th century was marked by an intensive process of motorization of society. The development of road transport predetermined two distinct and contradictory trends. On the one hand, the achieved level of motorization reflects the technical and economic potential of the development of society, and on the other hand, it increases the scale of the negative impact on public health and the environment. Road transport is one of the most important components of the country's transport support. In recent years, road transport carries out about 60% of cargo transportation and about 55% of passenger transportation, and taking into account personal cars - at least 65% of passengers. (See Appendix Graph 1) These figures continue to increase. Environmental problems associated with the use of vehicles are relevant not only for us, but for all countries of the world. relevance This problem is the increasing number of road transport and the increase in the degree of its negative impact on the environment and public health. Target: studying the impact of road transport on the environment and determining the main directions for improving its environmental safety. Goal setting involves the definition of a number of tasks: 1. Consider the impact of road transport on the environment. 2. Identify the main environmentally polluting substances produced by road transport. 3. Determine the main directions for improving environmental friendliness Automobile transport. Hypothesis: If you completely abandon the use of gasoline and diesel fuel in a car, then one of the most priority fuels in terms of economy and environmental friendliness will be gas. 1. The impact of toxic components produced by road transport on the environment. Not only drivers know what smells from the exhaust pipe of a car. Citizens are so accustomed to the smell of exhaust gases that sometimes they do not even feel it. In addition to the motorway, cars fill all local driveways and residential yards. Under certain weather conditions, children of asphalt, accustomed to car fumes, have to state an excessive content of exhaust gases in the city air. Thus, in terms of environmental damage, motor transport leads in all types of negative impacts: air pollution - 95%, noise - 49.5%, climate impact - 68% (see appendix graph 2). Fuel and exhaust gases of car engines affect the human body in different ways, but lead and its compounds are the most toxic. With carbon monoxide poisoning, headaches, suffocation, abdominal pain and vomiting, drowsiness, and palpitations appear. Nitric oxide in combination with water vapor forms nitric acid, which irritates the lung tissue, which leads to chronic diseases. Nitrogen dioxide irritates the mucous membrane of the eyes, lungs and causes irreversible changes in the cardiovascular system. Lead compounds cause metabolic and hematopoietic disorders in the body. Drivers, traffic workers and pedestrians in big cities are subject to this kind of poisoning. Pollution of the environment with toxic components of exhaust gases leads to large economic losses. This is primarily due to the fact that toxic substances cause disturbances in plant growth, lead to reduced yields and losses in animal husbandry. Accumulating in plants, they create a danger to animals and people. Particularly dangerous are the strips of land along the roads; with high traffic intensity, only industrial crops are allowed to be sown on them. Ground and surface waters are more exposed to the risk of pollution from fuels, oils and lubricants. A film of hydrocarbons on the surface of the water hinders the processes of oxidation, negatively affects living organisms and changes the quality of the water. Exhaust gases contribute to the acceleration of the destruction of plastic and rubber products, galvanized surfaces and ferrous metals, as well as painting, cladding and building structures. 2. The main pollutants entering the atmospheric air with the exhaust gases of vehicles As a result of environmental pollution by harmful substances from the exhaust gases of internal combustion engines, entire regions, especially large cities, become an ecological disaster zone for the population. The problem of further reduction of harmful engine emissions is becoming more and more aggravated due to the continuous increase in the number of road transport, the compaction of traffic flows. Consider the indicators of the increase in the number of road transport in the Poronaisky district of the Sakhalin region (see appendix. Table 1). This table shows that, on average, road transport in the Poronaisky district of the Sakhalin region increased by 300 units per year. This means that the amount of pollutants released into the atmosphere is increasing every year. The most unfavorable modes of operation are low speeds and "idling" of the engine, when pollutants are emitted into the atmosphere in quantities that significantly exceed the release at load modes. This can be seen in the table, which represents the characteristics of the rhythm of the car (see Appendix. Tab. 2). For example, if we take a 1 hour trip around the city, the car will sit at intersections and in traffic jams for approximately 24 minutes, i.e. 40% of the time the engine will idle. During this time, about 15% of the fuel from the total consumption for this hour will be consumed. The volume of exhaust gases during engine idling (for 24 minutes) will be 10% of their total volume emitted per hour. They will contain about 20% carbon monoxide (CO) and about 17% hydrocarbons (CnHm) of the total amount of these substances emitted on average per hour of city traffic. When considering the table, it can be seen that the chemical composition of pollutants depends on the type of fuel. (See Appendix. Tab. 3) The main toxic component of exhaust gases emitted during the operation of gasoline engines is carbon monoxide. It is formed during the incomplete oxidation of fuel carbon due to a lack of oxygen in the entire volume of the engine cylinder or in its individual parts. 3.Main directions for improving the environmental safety of cars. Most scientists and practitioners are taking urgent measures to reduce the toxicity of engine exhaust gases. The problem, of course, is very complex, time-consuming and costly. 3.1. Improvement of the internal combustion engine Numerous attempts have been made to improve its efficiency and environmental friendliness. To date, this is, first of all, fuel efficiency and the ability to meet international environmental requirements. Well-established technology for the production of internal combustion engines ensured their low unit cost (costs/kW of energy). Improvement of the working process has led to a high volumetric (mass) energy intensity (kW/kg, kW/m3). Researches of many generations of scientists and engineers have discovered that this design has untapped reserves for further development and improvement of the design. For example, a significant increase in efficiency gasoline engines and the improvement in efficiency was achieved due to: the transition to fuel injection into the intake manifold or directly into the cylinder; use of boost. From the point of view of ecology, the situation in the internal combustion engine is a dead end. A lot of fuel and little air - low power, efficiency and a lot of CO. Little fuel and a lot of air - a lot of nitric oxide. Until recently, a successful compromise was achieved by electronic control of the fuel-air ratio and the use of a so-called three-way catalytic converter. However, combustors capable of burning ultra-lean air-fuel mixtures have already been developed. Internal combustion engines with such chambers operate in all modes at almost ideal fuel-to-air ratios, therefore, they contain a minimum amount of harmful substances in the exhaust gases. 3.2. Electric car. The main advantages of an electric car: No harmful emissions; Simplicity of design and control, high reliability and durability in comparison with a conventional car; Disadvantages of an electric car: Over a century and a half of evolution, batteries have not reached the characteristics that allow an electric car to compete on equal terms with a car in terms of range and cost. Available high-energy batteries are either too expensive due to the use of precious or expensive metals (silver, lithium), or operate at too high temperatures. In addition, these batteries have a high self-discharge. A problem is the production and disposal of batteries, which often contain toxic components (such as lead or lithium). The mass use of electric vehicles requires the creation of an appropriate infrastructure for recharging batteries (charging at "car charging" stations). The main disadvantage today is the high cost. 3.3 Gas instead of gasoline High-octane, compositionally stable gas fuel mixes well with air and is evenly distributed over the engine cylinders, contributing to a more complete combustion of the working mixture. The total emission of toxic substances from cars running on liquefied gas is much less than cars with gasoline engines. So, the ZIL-130 truck, converted to gas, has a toxicity indicator almost 4 times less than its gasoline counterpart. When the engine is running on gas, a more complete combustion of the mixture occurs. And this leads to a decrease in the toxicity of exhaust gases, a decrease in carbon formation and oil consumption, and an increase in engine life. In addition, LPG is cheaper than gasoline. (see tab. No. 4) The problem of transferring vehicles to natural gas is a solution to a complex of complex tasks, among which the most significant are: mass production of gas-balloon vehicles; creation of infrastructure (network) of gas stations; development and production of reliable gas-balloon equipment; creation of a service network for the re-equipment of vehicles; personnel training; legal and advertising and information support, etc. Gasification of vehicles is not only a solution to environmental problems, but also saving budgetary funds (motor fuel from natural gas costs half as much as oil). Thus, the mass transfer of domestic cars to natural gas is the most rational, resource-provided and environmentally acceptable way to increase the efficiency and greening of Russian road transport. Conclusion It can be concluded that the foregoing determines the need to take large-scale and comprehensive measures to prevent, neutralize or at least significantly reduce the negative consequences that are generated by the motorization of our country. Unfortunately, a complete solution to the problem of urban air pollution by motor vehicles is not possible even with the use of only diesel or LPG vehicles. The use of unleaded gasoline reduces lead emissions but does not eliminate other pollutants. Diesel engine emissions are lead-free and low in carbon monoxide, but contain more nitrogen oxides. In addition, emissions from inadequately tuned diesel engines are enriched with soot containing carcinogens, hydrocarbons and formaldehydes. Of course, LPG engines are not ideal, but they are characterized by a much less detrimental effect on the environment, and therefore, they are preferable to other types of hydrocarbon engines.
Bibliography 8. S. Zhukov. Natural gas is the motor fuel of the 21st century. // Industry today, No. 2, 2001. - p. 12. 9. Gasoline, make room.//Factor, No. 3, 2001. - pp. 40-41. Application Chart 1 Chart 2 Table 1
table 2(Parameter values are given in percentage)
Table 3
Table 4
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