Traffic fumes
Permitted level in the European Union harmful substances in the exhaust depends on the age of the car. If the year of manufacture of the car is earlier than 1978, then there are no fixed restrictions, there is only one requirement that there is no visible smoke coming out of the exhaust pipe. If the car is manufactured in 1979-1986, then the maximum limit of harmful substances emitted by it, measured at idle, is as follows: CO - less than 4.5%, CH - 100 ppm. Oxygen should be less than 5%. The latter indicator is usually used to confirm that nothing illegal has been done to reduce the level of CO with the car's systems. From 1986 to 1990 in most countries the requirements became higher: CO - 3.5%, CH - 600 ppm. Since 1991, new regulations have been established for vehicles equipped with a catalytic afterburner. Now the level of harmful exhausts of the car is measured in two ways: at idle and at 2500 engine revolutions per minute. With the help of catalytic exhaust gas afterburner, the level of harmful emissions has been greatly reduced, for this reason, the emission limit values have also decreased. At idle, the CO level should be no more than 0.5% and CH no more than 100 ppm. At the same time, the so-called excess air coefficient alpha is calculated mathematically and should be between 0.91 - 1.03. Also the oxygen level must be less than 0.5% and the reference CO2 must be less than 16.
Owners of new cars have no problem getting permission to use their vehicles. Although, for example, in Finland the average age of a car is 10.5 years. But when the car has a significant mileage and age, when passing the exhaust test, it can be sent for repair.
Very often these problems are found in older cars, when the engine already has a significant mileage and has lost its former power. Often the owners do not notice that their car has already lost power.
The amount of exhaust gases of cars
Mainly determined mass flow fuel for cars. Consumption by distance is normalized and is usually indicated by manufacturers (one of the consumer characteristics). With regard to the total volume of exhaust gases coming out of the muffler, one can approximately focus on the following figure - one liter of gasoline burned leads to the formation of approximately 16 cubic meters or 16,000 liters of a mixture of various gases. Based on these data, one can judge the approximate amount of harmful impurities emitted into the atmosphere, but there is little problem. We can only determine the amount of different gases emitted during the combustion of a certain number of liters of fuel, but not with any exhaust, and even more so over a period of time (an hour, a day, a month, etc.). Therefore, we cannot, in principle, judge the amount of gases emitted into the atmosphere every hour. Nowhere is it established that all cars a day pass a certain number of kilometers at the same speed. And to look for some kind of average means to deceive yourself, because the data can be not only very approximate, but even completely erroneous.
Table number 1. Fuel consumption for cars of different brands
K -- carbureted engine
i -- injection engine
D -- diesel engine
the density of gasoline at +20C ranges from 0.69 to 0.81 g/cm³
density of diesel fuel at +20С according to GOST 305-82 no more than 0.86 g/cm³
Table number 2. Composition of automotive exhaust gases
Exhaust gases (or exhaust gases) - the main source of engine toxic substances internal combustion is a heterogeneous mixture of different gaseous substances with a variety of chemical and physical properties, consisting of products of complete and incomplete combustion of fuel coming from engine cylinders into its exhaust system. In their composition, they contain about 300 substances, most of which are toxic. The main regulated toxic components of engine exhaust gases are oxides of carbon, nitrogen and hydrocarbons. In addition, with exhaust gases saturated and unsaturated hydrocarbons, aldehydes, carcinogens, soot and other components enter the atmosphere. The approximate composition of exhaust gases is presented in table 1. When the engine is running on leaded gasoline, lead is present in the exhaust gases, and soot is present in engines running on diesel fuel. Now let's try to find out why each exhaust is dangerous, and what is the amount of gases escaping from the exhaust pipe.
Carbon monoxide (CO - carbon monoxide)
Transparent, odorless poisonous gas slightly lighter than air, poorly soluble in water. Carbon monoxide - a product of incomplete combustion of fuel, burns in air with a blue flame to form carbon dioxide (carbon dioxide). If its content is high, the engine consumes too much fuel and oil from the crankcase.
In the combustion chamber of an engine, CO is formed due to poor atomization of the fuel, as a result of cold flame reactions, during the combustion of fuel with a lack of oxygen, and also due to the dissociation of carbon dioxide during high temperatures. At the same time, the process of burning CO continues in the exhaust pipeline.
It should be noted that during the operation of diesel engines, the concentration of CO in the exhaust gases is low (approximately 0.1-0.2%), therefore, as a rule, the concentration of CO is determined for gasoline engines. On average, cars burning a liter of gasoline emit about 800 liters of carbon dioxide into the air.
Nitrogen oxides (NO, NO2, N2O, N2O3, N2O5, further - NOx)
Nitrogen oxides are among the most toxic components of exhaust gases. Under normal atmospheric conditions, nitrogen is a highly inert gas. At high pressures and especially temperatures, nitrogen actively reacts with oxygen. In the exhaust gases of engines, more than 90% of the total amount of NOx is nitric oxide NO, which is easily oxidized into dioxide (NO 2) even in the exhaust system, and then in the atmosphere.
Nitrogen oxides irritate the mucous membranes of the eyes, nose, and destroy human lungs, because when moving through the respiratory tract, they interact with the moisture of the upper respiratory tract, forming nitric and nitrous acids. As a rule, poisoning of the human body with NOx does not appear immediately, but gradually, and there are no neutralizing agents. When burning a liter of gasoline, approximately 128 liters of nitrogen oxides are emitted from the exhaust pipe.
Nitrous oxide (N 2 O - hemioxide, laughing gas) - a gas with a pleasant smell, we will dissolve well in water. Has a narcotic effect.
NO 2 (dioxide) is a pale yellow liquid involved in the formation of smog. Nitrogen dioxide is used as an oxidizing agent in rocket fuel. It is believed that for the human body, nitrogen oxides are about 10 times more dangerous than CO, and when secondary transformations are taken into account, they are 40 times more dangerous.
Nitrogen oxides are dangerous for plant leaves. It has been established that their direct toxic effect on plants manifests itself when the concentration of Nox in the air is in the range of 0.5-6.0 mg/m 3 . Nitric acid is highly corrosive to carbon steels.
The temperature in the combustion chamber has a significant effect on the emission of nitrogen oxides. So, with an increase in temperature from 2500 to 2700 K, the reaction rate increases by 2.6 times, and with a decrease from 2500 to 2300 K, it decreases by 8 times, i.e. the higher the temperature, the higher the NOx concentration. Early fuel injection or high pressures compression in the combustion chamber also contributes to the formation of NOx. The higher the oxygen concentration, the higher the concentration of nitrogen oxides.
Hydrocarbons (CnHm - ethane, methane, ethylene, benzene, propane, acetylene, etc.)
Hydrocarbons - organic compounds, the molecules of which are built only from carbon and hydrogen atoms, are toxic substances. Exhaust gases contain more than 200 different CHs, which are divided into aliphatic (open or closed chain) and those containing a benzene or aromatic ring. Aromatic hydrocarbons contain in the molecule one or more cycles of 6 carbon atoms interconnected by single or double bonds (benzene, naphthalene, anthracene, etc.). They have a pleasant smell. Its quantity is measured in the conventional unit ppm (number of particles per million). So even a slight increase in combustion efficiency can have a big impact on its level. Usually, extremely high level hydrocarbon is a problem not only for owners of cars, but also for mechanics.
The presence of CH in the exhaust gases of engines is explained by the fact that the mixture in the combustion chamber is heterogeneous, therefore, at the walls, in over-enriched zones, the flame is extinguished and chain reactions break. There are several factors that affect the amount of hydrocarbon in exhaust gases. Valve tightness, valve cleanliness and ignition timing are all equally important. Not only the ignition timing adjustment, but also the current combustion force, everything that affects combustion is of great importance in limiting the amount of hydrocarbon in the exhaust gases. Approximate quantity of the hydrocarbon which is formed at combustion of liter of gasoline - 400-450l.
These figures may scare someone, but let's figure it out: liters are a measure of volume, and in no case should these figures be confused with liquid, because 800 liters is a rather large number for a liquid. And for gas? A gas is a substance whose molecules are several hundred and thousand times smaller than the distance between them. If you imagine something denser, then the volume will be reduced by tens and hundreds of times. And now carefully - a liter of gasoline, during the combustion of which this volume is produced, is consumed to cover a distance of 10 km. Let's try to dispel most of the illusions - this is not such a strong pollution, it's just that an unpleasant smell is released at the moment of exhaust, and it seems to us that the composition of the air around has changed dramatically. But there was not even any sediment left on our clothes.
The main sources of vehicle emissions are the internal combustion engine, the evaporation of fuel through the ventilation system fuel tank, as well as the chassis: as a result of tire friction on pavement, wear of brake pads and corrosion of metal parts, regardless of engine emissions, fine dust particles are formed. Catalyst erosion releases platinum, palladium and rhodium, while clutch lining wear also releases toxic substances such as lead, copper and antimony. Limit values should also be set for these secondary vehicle emissions.
Harmful substances
Rice. Composition of exhaust gases
The composition of the exhaust (exhaust) gases of a car includes many substances or groups of substances. The predominant part of the exhaust gas components are non-toxic gases contained in normal air. As shown in the figure, only a small part of the exhaust gas is harmful to environment and people's health. Despite this, a further reduction in the concentration of toxic components of the exhaust gas is necessary. Although modern cars today produce very clean exhaust (Euro 5 cars are in some respects even cleaner than intake air), the huge number of cars in use, of which there are about 56 million units in Germany alone, emit a significant amount of poisonous and unhealthy substances. New technologies and the introduction of more stringent requirements for the environmental friendliness of exhaust gas are called upon to correct the situation.
Carbon monoxide (CO)
carbon monoxide(carbon monoxide) CO is a colorless and odorless gas. It is a poison for the respiratory system, disrupting the function of the central nervous and cardiovascular systems. In the human body, it binds red blood cells and causes oxygen starvation, which in a short time leads to death by suffocation. Already at a concentration in the air of 0.3% by volume, carbon monoxide kills a person in a very short time. The action depends on the concentration of CO in the air, on the duration and depth of inhalation. Only in an environment with a zero concentration of CO can it be excreted from the body through the lungs.
Carbon monoxide always occurs when there is a lack of oxygen and incomplete combustion.
Hydrocarbons (CH)
Hydrocarbons are emitted into the atmosphere in the form of unburned fuel. They have an irritating effect on the mucous membranes and respiratory organs of a person. Further optimization of the engine's workflow is only possible through improved production technologies and improved knowledge of combustion processes.
Hydrocarbon compounds occur as paraffins, olefins, aromas, aldehydes (especially formaldehydes) and polycyclic compounds. Experimentally proved carcinogenic and mutagenic properties of more than 20 polycyclic aromatic hydrocarbons, which, due to their small size, are able to penetrate to the pulmonary vesicles. The most dangerous hydrocarbon compounds are benzene (C6H6), toluene (methylbenzene) and xylene (dimethylbenzene, general formulaС6Н4 (CH3)2). For example, benzene can cause changes in the blood picture in a person and lead to the occurrence of blood cancer (leukemia).
The reason for the release of hydrocarbons into the atmosphere is always incomplete combustion of the fuel, lack of oxygen, and in the case of a very lean mixture, too slow combustion of the fuel.
Nitrogen oxides (NOx)
At a high combustion temperature (more than 1100°C), the reaction-inert nitrogen contained in the air is activated and reacts with free oxygen in the combustion chamber, forming oxides. They are very harmful to the environment: they cause smog, forest death, acid rain; nitrogen oxides are also transitional substances for the formation of ozone. They are poison to the blood, cause cancer. In the combustion process, various nitrogen oxides - NO, NO2, N2O, N2O5 - are formed, which have the general designation NOx. When combined with water, nitric (HNO3) and nitrous (HNO2) acids are formed. Nitrogen dioxide (NO2) is a red-brown poisonous gas with a pungent odor that irritates the respiratory system and forms compounds with blood hemoglobin.
This is the most problematic of all nitrogen oxides, and in the future separate standards for permissible concentrations will apply for it. The share of NO2 in total nitrogen oxide emissions in the future should be less than 20%. In directive 1999/30/EC, since 2010, the limit value for NO2 has been set at 40 µg/m. Observance of this limit value places special demands on protection against harmful emissions.
The most favorable conditions for the formation of nitrogen oxides are the high combustion temperature of lean air-fuel mixture. Exhaust gas recirculation systems reduce the proportion of nitrogen oxides in vehicle exhaust.
Sulfur oxides (SOx)
Sulfur oxides are formed from the sulfur contained in the fuel. During combustion, sulfur reacts with oxygen and water to form sulfur oxides, sulfuric (H2SO4) and sulfurous (H2SO3) acids. Sulfur oxide is the main constituent of acid rain and the cause of forest death. It is a water-soluble caustic gas, the effect of which on the human body is manifested by redness, swelling and increased secretion of moist mucous membranes of the eyes and upper respiratory tract. Sulfur dioxide affects the mucous membranes of the nasopharynx, bronchi and eyes. The most common site of "attack" sulfur dioxide are the bronchi. The strong irritant effect on the respiratory tract is due to the formation of sulfurous acid in a humid environment. Sulfur dioxide SO2 suspended in fine dust and sulfuric acid aerosol get deep into the respiratory tract. Asthmatics and young children are most sensitive to the growing concentration of sulfur dioxide in the air. High content sulfur in fuel shortens the life of catalysts in gasoline engines.
The reduction of sulfur dioxide emissions is realized by limiting the sulfur content in the fuel. The goal is a sulfur-free fuel.
Hydrogen sulfide (H2S)
The consequences of the impact of this gas on organic life are not yet entirely clear to science, but it is known that in humans it can cause severe poisoning. In severe cases, there is a threat of suffocation, loss of consciousness and paralysis of the central nervous system. In chronic poisoning, irritation of the mucous membranes of the eyes and respiratory tract is noted. The smell of hydrogen sulfide is already felt at its concentration in the air in the amount of 0.025 ml/m3.
Hydrogen sulfide in exhaust gases occurs under certain conditions, and, despite the presence of a catalyst, and depends on the sulfur content in the fuel.
Ammonia (NH3)
Inhalation of ammonia results in respiratory irritation, coughing, shortness of breath and choking. Ammonia also causes inflamed redness on the skin. Direct ammonia poisoning is rare, as even large amounts of it are rapidly converted to urea. When large amounts of ammonia are directly inhaled, lung function is often impaired for many years. This gas is especially dangerous for the eyes. With a strong effect of ammonia on the eyes, clouding of the cornea and blindness can occur.
Under certain conditions, ammonia can even form in the catalyst. At the same time, ammonia is useful as a reducing agent for SCR catalysts.
Soot and particles
Soot is pure carbon and an undesirable product of the incomplete combustion of hydrocarbons. The reason for the formation of soot is the lack of oxygen during combustion or premature cooling of the combustion gases. Soot particles often bind to unburned fuel and engine oil, as well as water, engine wear, sulfates and ash. Particles vary greatly in shape and size.
Table. Particle classification
The table shows the classification and particle sizes. Most often, when the engine is running, particles with a diameter of about 100 nanometers (0.0000001 m or 0.1 microns) are formed; such particles can naturally enter the lungs of a person. During agglutination (gluing) of soot particles with each other and other components, the mass, number and distribution of particles in the air can change significantly. The main components of the particles are shown in the figure.
Rice. Main components of particles
Due to its spongy structure, soot particles can capture both organic and inorganic substances formed during the combustion of fuel in engine cylinders. As a result, the mass of soot particles can increase three times. These will no longer be individual particles of carbon, but correct form agglomerates resulting from molecular attraction. The size of such agglomerates can reach 1 μm. Emissions of soot and other particles are especially active during the combustion of diesel fuel. These emissions are considered carcinogenic. Hazardous nanoparticles represent a quantitatively large proportion of particles, but only a small percentage by mass. For this reason, it is proposed to limit the content of particles in the exhaust gas not by mass, but by quantity and distribution. In the future, differentiation between particle size and particle distribution is envisaged.
Rice. Particle Composition
Particle emissions from gasoline engines are two to three orders of magnitude lower than from diesel engines. However, these particles are found even in the exhaust of gasoline engines with direct injection fuel. Therefore, there are proposals to limit the maximum content of particles in the exhaust gases of vehicles. Sublimation is the direct transition of a substance from a solid to a gaseous state, and vice versa. A sublimate is a solid precipitate of a gas when it is cooled.
fine dust
During the operation of internal combustion engines, especially fine particles are also formed - dust. It consists mainly of particles of polycyclic hydrocarbons, heavy metals and sulfur compounds. Part of the dust fractions is able to penetrate into the lungs, other fractions do not penetrate into the lungs. Fractions larger than 7 microns are less dangerous, as they are filtered out by the human body's own filtration system.
A different percentage of smaller fractions (less than 7 microns) penetrate the bronchi and pulmonary vesicles (alveoli), causing local irritation. In the region of the pulmonary vesicles, soluble components enter the bloodstream. The body's own filtration system does not cope with all fractions of fine dust. Atmospheric dust pollution is also called aerosols. They can be in a solid or liquid state and, depending on the size, can have a different period of existence. When moving, the smallest particles can combine into larger ones with a relatively stable period of existence in the atmosphere. These properties are mainly possessed by particles with a diameter of 0.1 µm to 1 µm.
When assessing the formation of fine dust as a result of work car engine it is necessary to distinguish this dust from the dust formed naturally: plant pollen, road dust, sand and many other substances. The sources of fine dust in cities, such as wear on brake pads and tires, should not be underestimated. So diesel exhaust is not the only "source" of dust in the atmosphere.
Blue and white smoke
blue smoke occurs during work diesel engine at temperatures below 180°C due to the smallest condensing oil droplets. At temperatures above 180°C, these droplets evaporate. Unburned hydrocarbon fuel components are involved in the formation of blue smoke and at temperatures from 70°C to 100°C. A large amount of blue smoke indicates a lot of wear. piston-cylinder group, stems and valve guides. Too late start of fuel supply can also cause blue smoke.
White smoke consists of water vapor generated during combustion of fuel and becomes noticeable at temperatures below 70°C. Particularly characteristic is the appearance white smoke for pre-chamber and vortex-chamber diesel engines after a cold start. White smoke is also caused by unburned hydrocarbon components and condensates.
Carbon dioxide (CO2)
Carbon dioxide It is a colorless, non-flammable, sour-tasting gas. It is sometimes erroneously called carbonic acid. The density of CO2 is about 1.5 times higher than the density of air. Carbon dioxide is integral part of air exhaled by a person (3-4%) When inhaling air containing 4-6% CO2, a person has headaches, tinnitus and heart palpitations, and at higher concentrations of CO2 (8-10%), asthma attacks occur, loss consciousness and respiratory arrest. At a concentration of more than 12%, death from oxygen starvation occurs. For example, a burning candle goes out at a CO2 concentration of 8-10% by volume. Although carbon dioxide is an asphyxiant, it is not considered poisonous as a component of engine exhaust. The problem is that carbon dioxide, as shown in the figure, contributes significantly to the global greenhouse effect.
Rice. Share of gases in the greenhouse effect
Together with it, methane, nitrous oxide (laughing gas, dinitrogen oxide), fluorocarbons and sulfur hexafluoride contribute to the development of the greenhouse effect. Carbon dioxide, water vapor and microgases affect the radiation balance of the Earth. Gases transmit visible light but absorb heat reflected from the earth's surface. Without this heat-holding capacity, the average temperature on the Earth's surface would be around -15°C.
This is called the natural greenhouse effect. With an increase in the concentration of microgases in the atmosphere, the proportion of absorbed thermal radiation increases and an additional greenhouse effect occurs. According to experts, by 2050 the average temperature on Earth will increase by +4°C. This can lead to a rise in sea level of more than 30 cm, as a result of which mountain glaciers and polar ice caps will begin to melt, the direction of sea currents (including the Gulf Stream) will change, air currents will change, and the seas will flood vast expanses of land. This is what greenhouse gases produced by human activities can lead to.
The total anthropogenic CO2 emissions are 27.5 billion tons per year. At the same time, Germany is one of the largest sources of CO2 in the world. Energy-related CO2 emissions average about a billion tons per year. This is about 5% of all CO2 produced in the world. The average family of 3 in Germany produces 32.1 tons of CO2 per year. CO2 emissions can only be reduced by reducing energy and fuel consumption. As long as energy is produced by burning fossil fuels, the problem of creating excessive amounts of carbon dioxide will persist. Therefore, the search for alternative energy sources is urgently needed. The automotive industry is working intensively to solve this problem. However, the greenhouse effect can only be combated on a global scale. Even if great progress is made within the EU in reducing carbon dioxide emissions, other countries may, on the contrary, see a significant increase in emissions in the coming years. The US leads by a wide margin in greenhouse gas production, both in absolute terms and on a per capita basis. With a share of only 4.6% of the world's population, they produce 24% of the world's carbon dioxide emissions. This is about twice as much as in China, whose share in the world's population is 20.6%. The 130 million cars in the US (less than 20% of the total number of cars on the planet) produce as much carbon dioxide as the entire industry in Japan, the world's fourth-largest CO2 emitter.
Without additional measures climate protection, global CO2 emissions will increase by 39% by 2020 (relative to 2004) and amount to 32.4 billion tons per year. In the next 15 years, carbon dioxide emissions in the United States will increase by 13% and exceed 6 billion tons. In China, we should expect an increase in CO2 emissions by 58%, to 5.99 billion tons, and in India - by 107%, to 2.29 billion tons. m. In the EU, on the contrary, the increase will be only about one percent.
Khairullin Danil - 6th grade
"He who does not know mathematics cannot learn any
another science and cannot even reveal his ignorance.
Roger Bacon
Due to the increase in the number of cars at the present time, the study of the transport factor of atmospheric pollution becomes relevant.
The purpose of this research work- using simple mathematical calculations to prove the problem of air pollution with exhaust gases in Bik-Uteevsky rural settlement. Exhaust emissions are the main reason for exceeding the permissible concentrations of toxic substances in the atmosphere and the formation of smog. With regard to the total volume of exhaust gases leaving the muffler of a car, one can approximately focus on the following figure - one kilogram of gasoline burned leads to the formation of approximately 16 kilograms of a mixture of various gases. Nitrogen oxides are the most dangerous, about 10 times more dangerous than carbon monoxide.
It turns out that prolonged contact with an environment poisoned by car exhaust gases causes a general weakening of the body - immunodeficiency. In addition, the gases themselves can cause various diseases.
The main sources of air pollution in my village are cars and agricultural machinery and their exhaust gases. I think as soon as possible we need to come up with harmless fuels, for example, using solar or water energy.
Every locality should have a green zone, which should serve as "green lungs". We know that trees purify the air by absorbing carbon dioxide and release oxygen, trap dust (for example, poplar).
In this work, I tried to reveal the essence of the problem associated with pollution by mathematical calculations. atmospheric air, find out why this problem is the number one threat to humanity.
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MBOU "Bik-Uteevskaya basic comprehensive school of the Buinsky municipal district of the Republic of Tatarstan"
Approximate calculation
exhaust gas damage
By Bik-Uteevsky Rural Settlement
Khairullin Danil Rifatovich,
- Class,
Head of Research:
Salavatullina Farida Fidailovna,
mathematic teacher
MBOU "Bik-Uteevskaya OOSh Buinsky m.r. RT"
year 2013
- Introduction
- theoretical part.
- Practical part.
3.2. Approximate calculation emissions of harmful substances by cars.
3.3. Approximate calculation of emissions of harmful substances by the tractor fleet of LLC SHP "Bola".
4. Conclusion.
5. List of references.
Introduction
"Those who do not know mathematics,
can't learn any other science
and can't even show his ignorance"
Roger Bacon
On September 16, 1987, the Montreal Protocol on Substances that Deplete the Ozone Layer was adopted. Subsequently, at the initiative of the UN, this day began to be celebrated as the Day for the Protection of the Ozone Layer. September 16 of this academic yearwithin international day the ozone layer in our school there was a republican environmental action "Lesson of cleanliness". The action was held in the form of a conversation, during which we in an accessible form got acquainted with such concepts as ozone, the ozone layer, with information about the significance of the ozone layer, about the causes of its destruction and methods of restoration.There are many reasons for the weakening of the ozone shield. Firstly, these are launches of space rockets,burning fuel "burns out" large holes in the ozone layer. It was once thought that these "holes" are being closed. It turned out not. They have been around for quite some time.
Yes, the danger of irreversible changes in nature is becoming real. Scientists are sounding the alarm: life on Earth is on the brink of an ecological disaster. According toWorld Conservation Union over the past 500 years, 844 species of animals have completely died out, and 23%mammals and 16% birds in the world are in danger of extinction. 1 billion tons of fuel are burned annually, hundreds of million tons are emitted into the atmospherenitrogen oxides , sulfur , carbon , some of them are returned asacid rain , soot , ash And dust . Soils and waters are polluted by industrial and domestic effluents and other wastes.
The information received made me think: What awaits us - new problems or a cloudless future? What will humanity be like in 100, 200 years? Will a person with his mind and will be able to save himself and our planet from the threats hanging over it? What exactly can I do to save our planet?
After all, not only spaceships and factory chimneys pollute the air of our planet, there are also cars that daily emit numerous tons of toxic gases and vapors, products of combustion of chemicals, into the atmosphere around the world.So the car is also a source of environmental pollution? And in connection with the increase in the number of cars at the present time, the study of the transport factor of atmospheric pollution becomes relevant.
The purpose of my research work is to prove the problem of air pollution by exhaust gases of motor vehicles and agricultural machines by the method of simple mathematical calculations in the Bik-Uteevsky rural settlement.
To achieve this goal, I have identified the following tasks:
1. Study the literature on this issue.
2. Determine the impact of vehicle exhaust gases on human and animal health.
4. Conduct an approximate calculation of the possible reduction of air pollution during tree planting.
Methods of my research: surveys and questionnaires, mathematical calculations using a microcalculator, data comparison.
theoretical part.
Today it is difficult to imagine human civilization without a car.But the fact that the machine from the blessing of civilization can turn into its scourge, mankind began to understand relatively recently. Cars burn a huge amount of oil products, causing significant damage to the environment, mainly the atmosphere.
From a page on the Wikipedia website, I learned the following concepts. Exhaust or waste gases are products of oxidation and incomplete combustion hydrocarbon fuel. Exhaust emissions are the main reason for exceeding the permissible concentrations of toxic substances in the atmosphere and the formation of smog. With regard to the total volume of exhaust gases leaving the muffler of a car, one can approximately focus on the following figure - one kilogram of gasoline burned leads to the formation of approximately 16 kilograms of a mixture of various gases.
Further I studied approximate composition automobile exhaust gases, some names I still do not quite understand, but I present their % content (Table No. 1). The composition of exhaust gases also includes non-toxic substances, these are nitrogen, oxygen, hydrogen, water vapor, carbon dioxide. And I highlighted toxic substances and carcinogens in bold.Nitrogen oxides are the most dangerous, about 10 times more dangerous than carbon monoxide (CO).
Table #1
N 2 vol.% | 74-77 | 76-78 |
O 2 vol.% | 0,3-8,0 | 2,0-18,0 |
H 2 O (pairs), vol.% | 3,0-5,5 | 0,5-4,0 |
CO 2 vol.% | 0,0-16,0 | 1,0-10,0 |
*, about.% (carbon monoxide) | 0,1-5,0 | 0,01-0,5 |
nitrogen oxides *, about.% | 0,0-0,8 | 0,0002-0,5 |
hydrocarbons *, about.% | 0,2-3,0 | 0,09-0,5 |
Aldehydes *, about.% | 0,0-0,2 | 0,001-0,009 |
Soot **, g/m 3 | 0,0-0,04 | 0,01-1,10 |
Benzpyrene -3.4**, g/m3 | 10-20 10 −6 | 10×10 −6 |
It turns out that prolonged contact with an environment poisoned by car exhaust gases causes a general weakening of the body - immunodeficiency. In addition, the gases themselves can cause various diseases. For example, respiratory failure, sinusitis, bronchitis, pneumonia, lung cancer. Exhaust gases also cause atherosclerosis of cerebral vessels, various disorders of the cardiovascular system may occur.Scientists have noticed that dogs, cats, and other small animals are susceptible to more at risk, since the exhaust pipes of cars are located at a small distance from the ground and it is our smaller brothers who become the first to receive their share of the exhaust.
- Practical part.
3.1. Collection and processing of information.
To achieve this goal, I turned to the Bik-Uteevsky Village Council with a request to provide information on the number of inhabitants And vehicles. According to the Village Council at the beginning of the year in Bik-UteevskyRural settlement517 people registered, including children preschool age 38, 132 pensioners over 70; 72 cars of various brands. This means that every seventh resident has a personal vehicle.
Secondly, I contacted the accounting department of LLC SHP "Bola" with a request to assist in the calculation of the content of exhaust gases during agricultural work. I entered the data obtained in table number 2.
Table number 2
p/p | Vehicle name | Engine type | Quantity, pcs | Worked out in 1 year | |
Km. mileage | Reference hectare |
||||
Trucks of various brands | Diesel | 202 590 | |||
Petrol | 296 126 | ||||
Wheel tractors various brands | Diesel | 1748 |
|||
various brands | Diesel | 1163 |
|||
Combine harvesters various brands | Diesel | ||||
Forage harvesters | Diesel |
Thirdly, I conducted a survey of my peers and teachers of the school, whom I asked the following questions:
- Do you have a car?
- What type of fuel does it use?
- Average car mileage per year?
The survey involved 20 people. As a result, I received the following data:
Table No. 3
Questionnaire No. | Question #1 | Question #2 | Question #3 | Questionnaire No. | Question #1 | Question #2 | Question #3 |
Yes | petrol | 48100 | Yes | petrol | 30800 |
||
Yes | petrol | 8900 | Yes | petrol | 28000 |
||
Yes | petrol | 15000 | Yes | petrol | 45000 |
||
No | Yes | petrol | 20000 |
||||
Yes | petrol | 32000 | Yes | petrol | 22000 |
||
Yes | petrol | 30100 | Yes | petrol | 18000 |
||
Yes | petrol | 7500 | Yes | petrol | 17000 |
||
Yes | petrol | 23000 | Yes | petrol | 21000 |
||
No | Yes | petrol | 17000 |
||||
Yes | petrol | 35000 | Yes | petrol | 13500 |
Of the 20 respondents, 18 own cars. The average mileage of one car in one year is approximately 26,600 km. The main type of fuel is gasoline.
Then I did the math.Used in calculationsguidelines for performing settlement and practical workwhen calculating harmful emissions.
Harmful substances emitted by motor vehicles include carbon monoxide, hydrocarbons and nitrogen oxides.
The amount of emissions of harmful substances from vehicles into the atmosphere can be estimated by the calculation method. The initial data for the calculation are:
Total mileage of vehicles for the year;
Transport fuel consumption rates;
Table No. 4
The value of the coefficient that determines the emission of harmful substances from vehicles, depending on the type of fuel, is given in Table. 5.
Table number 5
The coefficient is numerically equal to the amount of harmful emissions of the corresponding component in liters during the combustion in the car engine of the amount of fuel (in liters) required to travel 1 km.
3.2 Calculation of emissions of harmful substances by cars.
I entered the calculation of fuel consumption in table No. 6.
Type transport | Number of cars abundance, pcs | Average mileage per year, km. | Total mileage, km | Fuel consumption per 1 km, liter | |
26600 | 1915200 | 0,12 | 229864 |
||
296126 | 88838 |
||||
202590 | 0,35 | 70906 |
Then I calculated the amount of harmful substances released from vehicles and entered it in table No. 7.
Type transport | Total fuel consumption per year, liter | The total amount of harmful substances per 1 liter, liter | Total total amount of harmful substances, liter |
A car | 229864 | 0,74 | 170099 |
Truck with petrol engine | 88838 | 0,74 | 65740 |
Diesel freight car | 70906 | 0,17 | 12054 |
Total | 274893 |
The resulting numbers frightened me, really so much? Then the teacher explained to me: “Let's figure it out, in no case should you be confused. For a liquid, this is quite a large number. But not for gas? In gases, the distance between molecules is much more sizes the molecules themselves.A gas can be compressed so that its volume decreases several times. If you imagine something denser, then the volume will be reduced by tens and hundreds of times. Try to dispel the illusions."
- Calculation of emissions of harmful substances by the tractor fleet of LLC SHP "Bola".
In one year, the farm worked out 3930 standard hectares, spent 27510 kg of fuel. When calculating, it is necessary to take into account engine power and types of work, so I took approximate values.
Mass release of pollutants | Total | |||
carbon monoxide | nitrogen oxides | hydrocarbons | ||
g/kg | 48.8 | 0.17 | ||
Kg per 3930 fl.ha | 117.9 | 9359 | 9598.4 |
So, I calculated the approximate amount of emissions of harmful substances into the air from transport in my rural settlement in one year. Is it a lot or a little. On the scale of my village, it is probably not enough, but if these figures are translated into large cities, where, in addition to vehicles, there is also industrial waste, it will turn out to be a huge figure.
3.4. Approximate calculation of the possible reduction of air pollution when planting trees.
In my investigations, I found the following facts:over the summer, one adult tree can purify the air from 20-30, and some species even from 50 kg of harmful substances and dust.One of the best breeds is poplar. It is he who copes with exhaust gases better than all other trees. I calculated that there are about 40 km of forest plantation along the roads in my rural settlement, this is 25,000 trees.
In a rural settlement, the total working population is 517 - (38 + 132) = 347 people. If every person from 7 to 70 years old plants one tree every year, then we will help nature cleanse itself of 10 tons of harmful substances and dust.
Conclusion
In this work, I tried to reveal the essence of the problem associated with air pollution by mathematical calculations, to find out why this problem is the number one threat to humanity. In conclusion, I would like to say thatIn the course of work, I learned a lot of new things and I can draw the following conclusions:
- Without mathematical knowledge, it is impossible to imagine the menacing scale of human impact on the environment.
- The main sources of air pollution in my village are motor vehicles and their exhaust gases. I think as soon as possible we need to come up with harmless fuels, for example, using solar or water energy.
- Each settlement should have a green zone, which should serve as a "green lung". We know that trees purify the air by absorbing carbon dioxide and release oxygen, trap dust (for example, poplar). This information for me is not unimportant.
I shared my findings with my peers and teachers.
Bibliography:
- Guidelines for the implementation of settlement and practical work. Uch.-ed. Publishing house of the Arkhangelsk State Technical University, 2004
- Guidelines for calculating the emission of harmful substances by road transport. Moscow. Gidrometizdat. 2005
- http://en.wikipedia.org/wiki/
- Kazantseva L.K., Tagaeva T.O. Modern ecological situation in Russia // ECO. – 2005.
Tasks: 1 . Study the literature on this issue. 2. Determine the impact of vehicle exhaust gases on human and animal health. 3 . Calculate the approximate amount of emissions of harmful substances into the air from transport in my rural settlement. 4 . Conduct an approximate calculation of the possible reduction of air pollution when planting trees.
Today it is difficult to imagine human civilization without a car. Exhaust emissions are the main reason for exceeding the permissible concentrations of toxic substances in the atmosphere and the formation of smog. With regard to the total volume of exhaust gases leaving the muffler of a car, one can approximately focus on the following figure - one kilogram of gasoline burned leads to the formation of approximately 16 kilograms of a mixture of various gases. kilograms of a mixture of various gases.
Exemplary composition of automotive exhaust gases Gasoline engines Diesels N 2, vol.% 74-77 76-78 O 2, vol.% 0.3-8.0 2.0-18.0 H 2 O (vapors), vol. % 3.0-5.5 0.5-4.0 CO 2, vol.% 0.0-16.0 1.0-10.0 CO *, vol.% (carbon monoxide) 0.1-5 .0 0.01-0.5 Nitrogen oxides *, vol.% 0.0-0.8 0.0002-0.5 Hydrocarbons *, vol.% 0.2-3.0 0.09-0.5 Aldehydes *, vol.% 0.0-0.2 0.001-0.009 Soot **, g/m3 0.0-0.04 0.01-1.10 Benzpyrene -3.4**, g/m3 10-20 10 −6 10 × 10 −6
Exhaust gases are the cause of various diseases. For example, respiratory failure, sinusitis, bronchitis, pneumonia, lung cancer. Exhaust gases also cause atherosclerosis of cerebral vessels, various disorders of the cardiovascular system may occur.
Scientists have noticed that dogs, cats, and other small animals are more at risk, since the exhaust pipes of cars are located at a small distance from the ground and our smaller brothers are the first to receive their share of the exhaust.
Collection and processing of information According to the Village Council, at the beginning of the year, 517 people were registered in the Bik-Uteevsky rural settlement, including children of preschool age 38, 132 pensioners over 70; 72 cars of various brands. This means that every seventh resident has a personal vehicle.
received the following data to the accounting department of LLC SHP "Bola": Collection and processing of information No. p / p Name of the vehicle Type of engine Quantity, pcs Worked out for 1 year Km. Mileage Standard Hectare 1. Trucks of various stamps diesel 4 202 590 gasoline 8 296 126 2. Wheel tractors of various grades diesel 12 1748 3. Caterpillar tractors of various grades diesel 17 1163 4. Grain combinations of various brands diesel 7 608 5. Diesel diesel feed combines 3 411
Collection and processing of information Interviewed peers and school teachers, who asked the following questions: Do you have a car? What type of fuel does it use? Average car mileage per year? Result: Of the 20 respondents, 18 own cars. The average mileage of one car in one year is approximately 26,600 km. The main type of fuel is gasoline.
Calculation of emissions of harmful substances by cars The amount of emissions of harmful substances from vehicles into the atmosphere can be estimated by the calculation method. The initial data for the calculation are: - the total mileage of vehicles for the year; - norms of fuel consumption by transport; - the value of the coefficient that determines the emission of harmful substances from vehicles, depending on the type of fuel.
Calculation of fuel consumption Coefficient values that determine the emission of harmful substances from vehicles Fuel type Carbon monoxide Hydrocarbons Nitrogen dioxide Gasoline 0.6 0.1 0.04 Diesel fuel 0.1 0.03 0.04 Type of transport Number of vehicles, pcs Average mileage per year, km. Total mileage, km Fuel consumption per 1 km, liter Total fuel consumption per year, liter Passenger car 72 26600 1915200 0.12 229864 Petrol truck 8 296126 0.3 88838 Diesel truck 4 202590 0.35 70906
Calculation of emissions of harmful substances by cars Type of transport Total fuel consumption for the year, liter Total amount of harmful substances per 1 liter, liter Total total amount of harmful substances, liter Passenger car 229864 0.74 170099 Truck with gasoline engine 88838 0.74 65740 Diesel truck 70906 0.17 12054 Total 274893
Calculation of emissions of harmful substances by the tractor fleet of LLC SHP "Bola" The farm worked out 3930 standard hectares in one year, spent 27510 kg of fuel. When calculating, it is necessary to take into account the engine power and types of work.
Calculation of emissions of harmful substances by the tractor fleet of LLC SHP "Bola" Mass emission of pollutants Total Carbon monoxide Nitrogen oxides Hydrocarbons g/kg 30 48.8 0.17 kg per 3930 fl.ha 117.9 9359 3.5 9598.4
Approximate calculation of the possible reduction of air pollution when planting trees Over the summer, one adult tree can purify the air from 20-30, and some species even from 50 kg of harmful substances and dust. One of the best breeds is poplar. In a rural settlement, the total working population is 347 people. If every person from 7 to 70 years old plants one tree, then we will help nature cleanse itself of 10 tons of harmful substances and dust.
Conclusions 1. Without mathematical knowledge, it is impossible to imagine the menacing scale of human impact on the environment. 2. The main sources of air pollution in my village are road transport and agricultural machinery, their exhaust gases. 3. Each settlement must have a green zone. We know that trees purify the air by absorbing carbon dioxide and release oxygen, trap dust (for example, poplar).
Now, thanks to the media, the planet is under the close attention of the public, namely its saturation and pollution with car exhaust gases. Especially closely people monitor and discuss such a by-product of widespread motorization as the “greenhouse effect” and the harm of diesel exhaust gases, which has been circulated in the press.
However, as exhaust gases are known, exhaust gases are different, despite the fact that they are all dangerous to the human body and other life forms on Earth. So what makes them dangerous? And what makes them different from each other? Let's look under a microscope of what the blue smog flying out of the exhaust pipe consists of. Carbon dioxide, soot, nitric oxide and some other equally dangerous elements.
Scientists note that the environmental situation in many industrialized and developing countries has improved significantly over the past 25 years. This is mainly due to the gradual but inevitable tightening environmental standards, as well as the transfer of production to other continents and other countries, including East Asia. In Russia, Ukraine, and other CIS countries, a large number of enterprises were closed due to political and economic shocks, which on the one hand created an extremely difficult socio-economic environment, but significantly improved the environmental performance of these countries.
However, according to research scientists, it is cars that pose the greatest danger to our green planet. Even with a gradual tightening of the standards for emissions of harmful substances into the atmosphere, due to an increase in the number of cars, the results of this work, alas, are leveled.
If we segment the total mass of various Vehicle currently present on the planet remain the dirtiest, especially dangerous cars with this type of fuel in excess of nitrogen oxide. Despite decades of development and assurances from automakers that they can make diesels cleaner, nitrous oxide and fine soot remain diesel's biggest enemy.
It is in connection with these problems associated with the use of diesel engines that large German cities such as Stuttgart and Munich are currently discussing a ban on the use of heavy fuel vehicles.
Here is a comprehensive list of harmful substances in exhaust gases and the harm caused to human health when they are inhaled.
Traffic fumes
Exhaust gases are gaseous wastes that occur in the process of converting liquid hydrocarbon fuel into energy on which the internal combustion engine operates by combustion.
Benzene
Benzene is found in small amounts in gasoline. Colorless, transparent, easily mobile liquid.
As soon as you fill your car's tank with gasoline, the first thing you'll come into contact with is the benzene that evaporates from the tank. But the most dangerous is benzene during fuel combustion.
Benzene is one of those substances that can cause cancer in humans. However, a decisive reduction in airborne hazardous benzene was achieved many years ago with a three-way catalyst.
Fine dust (solid particles)
This air pollutant is an undefined substance. It is better to say that it is a complex mixture of substances, which may differ in origin, form and chemical composition.
In automobiles, ultra-fine abrasive is present in all forms of operation, for example, when tires are worn and brake discs. But the greatest danger is soot. Previously, only diesel engines suffered from this unpleasant moment in operation. Thanks to the installation of particulate filters, the situation has improved significantly.
Now a similar problem appeared and petrol models, as they increasingly use direct fuel injection systems, resulting in co-production of even finer particulate matter than diesel engines.
However, according to scientists investigating the nature of the problem, only 15% of the fine dust deposited in the lungs is produced by cars, any human activity, from agriculture, to laser printers, fireplaces and, of course, cigarettes, can be a source of a dangerous phenomenon.
The health of residents of megacities
The actual load on the human body from exhaust gases depends on the volume of traffic and weather conditions. Someone who lives on a busy street is much more exposed to nitrogen oxides or fine dust.
Exhaust fumes are not equally dangerous for all residents. Healthy people will hardly feel a "gas attack" in any way, although the intensity of the load will not decrease from this, but the health of an asthmatic or a person with cardiovascular diseases can deteriorate significantly due to the presence of exhaust gases.
Carbon Dioxide (CO2)
Harmful to the entire climate of the planet, gas inevitably arises from the combustion of fossil fuels such as diesel or gasoline. In terms of CO2, diesel engines are slightly “cleaner” than gasoline engines because they generally consume less fuel.
CO2 is harmless to humans, but not to nature. The greenhouse gas CO2 is responsible for much of global warming. According to the German Federal Ministry for the Environment, in 2015 the share of carbon dioxide in total greenhouse gas emissions was 87.8 percent.
Since 1990, carbon dioxide emissions have been declining almost continuously, with a total decrease of 24.3 percent. However, despite the production of ever more efficient engines, the growth of motorization and the increase freight traffic undermines attempts by scientists and engineers to reduce harm. As a result, carbon dioxide emissions remain high.
By the way: all vehicles in, say, Germany are responsible for “only” 18 percent of CO2 emissions. More than twice as much, 37 percent, goes to energy emissions. In the US, the picture is the opposite, where it is cars that cause the most serious damage to nature.
Carbon monoxide (Co, carbon monoxide)
extremely dangerous by-product burning. Carbon monoxide is a colorless, tasteless and odorless gas. The combination of carbon and oxygen occurs during incomplete combustion of carbon-containing substances and is an extremely dangerous poison. Therefore, high-quality ventilation in garages and underground parking lots is essential for the life of their users.
Even a small amount of carbon monoxide causes damage to the body, a few minutes spent in a poorly ventilated garage with a car running can kill a person. Be extremely careful! Do not warm up in closed boxes and rooms without ventilation!
But how dangerous is carbon monoxide on outdoors? An experiment carried out in Bavaria showed that in 2016 the average values shown by the measuring stations were between 0.9-2.4 mg/m 3 , well below the limit values.
Ozone
For the layman, ozone is not some kind of dangerous or toxic gas. However, in reality this is not the case.
When exposed to sunlight, hydrocarbons and nitric oxide are converted into ozone. Through the respiratory tract, ozone enters the body and leads to cell damage. Consequences, effects of ozone: local inflammation of the respiratory tract, cough and shortness of breath. With small volumes of ozone, there will be no problems with the subsequent restoration of body cells, but at high concentrations, this seemingly harmless gas can safely kill a healthy person. It is not for nothing that in Russia this gas is classified as the highest hazard class.
With climate change, the risk of high concentrations of ozone is increasing. Scientists believe that by 2050 the ozone load should rise sharply. To solve the problem, nitrogen oxides emitted by transport must be significantly reduced. In addition, there are many factors influencing the spread of ozone, for example, solvents in paints and varnishes also actively contribute to the problem.
Sulfur dioxide (SO2)
This pollutant is produced when sulfur is burned in fuel. It is one of the classic atmospheric pollutants from combustion, power plants and industry. SO2 is one of the main "ingredients" of pollutants that form smog, also called "London smog".
In the atmosphere, sulfur dioxide undergoes a series of conversion processes that can produce sulfuric acid, sulfites and sulfates. SO2 acts primarily on the mucous membranes of the eye and upper respiratory tract. In the environment, sulfur dioxide can damage plants and cause soil acidification.
Nitrogen Oxides (NOx)
Nitrogen oxides are formed mainly during the combustion process in internal combustion engines. Diesel vehicles are considered the main source. The introduction of catalysts and particulate filters continues to increase, so that emissions will decrease markedly, but this will happen only in the future.
The formation of toxic substances - products of incomplete combustion and nitrogen oxides in the engine cylinder during the combustion process occurs in fundamentally different ways. The first group of toxic substances is associated with chemical reactions of fuel oxidation, occurring both in the pre-flame period and in the process of combustion - expansion. The second group of toxic substances is formed by the combination of nitrogen and excess oxygen in the combustion products. The reaction of formation of nitrogen oxides is thermal in nature and is not directly related to fuel oxidation reactions. Therefore, it is advisable to consider the mechanism of formation of these toxic substances separately.
The main toxic vehicle emissions include: exhaust gases (EG), crankcase gases and fuel fumes. Engine exhaust gases contain carbon monoxide (CO), hydrocarbons (C X H Y), nitrogen oxides (NO X), aldehydes and soot. Crankcase gases are a mixture of part of the exhaust gases that have penetrated through the leakage of the piston rings into the crankcase of the engine, with engine oil vapor. Fuel vapors enter the environment from the engine power system: joints, hoses, etc. Distribution of the main components of emissions from carburetor engine as follows: exhaust gases contain 95% CO, 55% C X H Y and 98% NO X, crankcase gases each contain 5% C X H Y, 2% NO X, and fuel vapors up to 40% C X H Y. IN general case The composition of the exhaust gases of engines may contain the following non-toxic and toxic components: O, O 2, O 3, C, CO, CO 2, CH 4, C n H m, C n H m O, NO, NO 2, N, N 2, NH 3 , HNO 3 , HCN, H, H 2 , OH, H 2 O.
Harmful toxic emissions can be divided into regulated and unregulated. They act on the human body in different ways. Harmful toxic emissions: CO, NO X, C X H Y, R X CHO, SO 2, soot, smoke. CO (carbon monoxide) This gas is colorless and odorless, lighter than air. It is formed on the surface of the piston and on the cylinder wall, in which activation does not occur due to the intensive heat removal of the wall, poor atomization of the fuel and the dissociation of CO 2 into CO and O 2 at high temperatures.
NO X (nitrogen oxides) is the most toxic gas from the exhaust gas.
N is an inert gas at normal conditions. Actively reacts with oxygen at high temperatures.
The exhaust gas emission depends on the ambient temperature. How more load engine, the higher the temperature in the combustion chamber, and accordingly the emission of nitrogen oxides increases.
Hydrohydrogens (C x H y)- ethane, methane, benzene, acetylene and other toxic elements. EG contains about 200 different hydrohydrogens.
In diesel engines, C x H y are formed in the combustion chamber due to a heterogeneous mixture, i.e. the flame goes out in a very rich mixture, where there is not enough air due to incorrect turbulence, low temperature, poor atomization.
The internal combustion engine emits more C x H y when operating in idle move, due to poor turbulence and reduced combustion rate.
Smoke is an opaque gas. Smoke can be white, blue, black. The color depends on the state of the exhaust gas.
White and blue smoke is a mixture of a drop of fuel with a microscopic amount of steam; formed due to incomplete combustion and subsequent condensation.
White smoke formed when the engine is cold, and then disappears due to heating. The difference between white smoke and blue smoke is determined by the droplet size: if the droplet diameter is greater than the wavelength of blue color, then the eye perceives the smoke as white.
Blue smoke comes from oil. The presence of smoke indicates that the temperature is insufficient for complete combustion of the fuel. Black smoke is made up of soot. Smoke adversely affects the human body, animals and vegetation.
Soot- is a shapeless body without a crystal lattice; in the exhaust gas of a diesel engine, soot consists of undefined particles with dimensions of 0.3 ... 100 microns.
The reason for the formation of soot is that the energy conditions in the cylinder of a diesel engine are sufficient to completely destroy the fuel molecule. The lighter hydrogen atoms diffuse into the oxygen-rich layer, react with it, and, as it were, isolate the hydrocarbon atoms from contact with oxygen. The formation of soot depends on temperature, pressure in the combustion chamber, type of fuel, fuel-air ratio.
SO 2 (sulfur oxide)- is formed during engine operation from fuel obtained from sour oil (especially in diesel engines); these emissions irritate the eyes and respiratory organs. SO 2, H 2 S - very dangerous for vegetation.
Lead is the main air pollutant in Russian Federation Leaded gasoline is currently the leading vehicle: from 70 to 87% of total lead emissions according to various estimates. PbO (lead oxides)- occur in the exhaust gas of carburetor engines when leaded gasoline is used. When burning one ton of leaded gasoline, approximately 0.5 ... 0.85 kg of lead oxides are emitted into the atmosphere. According to preliminary data, the problem of environmental pollution with lead from vehicle emissions becomes significant in cities with a population of over 100,000 people and for local areas along highways with heavy traffic. A radical method of combating environmental pollution with lead emissions road transport– Avoiding the use of leaded petrols.
Aldehydes (R x CHO) are formed when fuel is burned low temperatures or the mixture is very lean, and also due to the oxidation of a thin layer of oil in the cylinder wall. When fuel is burned at high temperatures, these aldehydes disappear.
Air pollution goes through three channels: 1) exhaust gases emitted through the exhaust pipe (65%); 2) crankcase gases (20%); 3) hydrocarbons as a result of fuel evaporation from the tank, carburetor and pipelines (15%).
