A small educational program for those who like to breathe from the exhaust pipe.

The exhaust gases of internal combustion engines contain about 200 components. The period of their existence lasts from a few minutes to 4-5 years. According to the chemical composition and properties, as well as the nature of the impact on the human body, they are combined into groups.

First group. It includes non-toxic substances (natural components of atmospheric air).

Second group. This group includes only one substance - carbon monoxide, or carbon monoxide (CO). The product of incomplete combustion of petroleum fuels is colorless and odorless, lighter than air. In oxygen and in air, carbon monoxide burns with a bluish flame, releasing a lot of heat and turning into carbon dioxide.

Carbon monoxide has a pronounced toxic effect. It is due to its ability to react with blood hemoglobin, leading to the formation of carboxyhemoglobin, which does not bind oxygen. As a result, gas exchange in the body is disturbed, oxygen starvation appears and there is a violation of the functioning of all body systems. Car drivers are often exposed to carbon monoxide poisoning. Vehicle when spending the night in the cab with the engine running or when the engine is warming up in a closed garage. The nature of carbon monoxide poisoning depends on its concentration in the air, the duration of exposure and the individual susceptibility of a person. A mild degree of poisoning causes a throbbing in the head, darkening of the eyes, increased heart rate. In severe poisoning, consciousness becomes clouded, drowsiness increases. At very high doses of carbon monoxide (over 1%), loss of consciousness and death occur.

Third group. It contains nitrogen oxides, mainly NO - nitrogen oxide and NO 2 - nitrogen dioxide. These are the gases that form in the chamber combustion engine at a temperature of 2800 ° C and a pressure of about 10 kgf / cm 2. Nitric oxide is a colorless gas, does not interact with water and is slightly soluble in it, does not react with solutions of acids and alkalis. Easily oxidized by atmospheric oxygen and forms nitrogen dioxide. Under normal atmospheric conditions, NO is completely converted into NO 2 - a brown-colored gas with a characteristic odor. It is heavier than air, therefore it collects in depressions, ditches and is a great danger during vehicle maintenance.

For the human body, nitrogen oxides are even more harmful than carbon monoxide. The general nature of exposure varies depending on the content of various nitrogen oxides. Upon contact of nitrogen dioxide with a wet surface (mucous membranes of the eyes, nose, bronchi), nitric and nitrous acids are formed, which irritate the mucous membranes and affect the alveolar tissue of the lungs. At high concentrations of nitrogen oxides (0.004 - 0.008%), asthmatic manifestations and pulmonary edema occur. Inhaling air containing nitrogen oxides in high concentrations, a person does not have unpleasant sensations and does not imply negative consequences. With prolonged exposure to nitrogen oxides in concentrations exceeding the norm, people get chronic bronchitis, inflammation of the mucous membrane of the gastrointestinal tract, suffer from heart weakness, as well as nervous disorders.

A secondary reaction to the effects of nitrogen oxides is manifested in the formation of nitrites in the human body and their absorption into the blood. This causes the conversion of hemoglobin to metahemoglobin, which leads to cardiac dysfunction.

Nitrogen oxides also have a negative effect on vegetation, forming solutions of nitric and nitrous acids on leaf plates. The same property determines the effect of nitrogen oxides on Construction Materials and metal constructions. In addition, they are involved in the photochemical reaction of smog formation.

Fourth group. This most numerous group includes various hydrocarbons, that is, compounds of the C x H y type. The exhaust gases contain hydrocarbons of various homologous series: paraffinic (alkanes), naphthenic (cyclanes) and aromatic (benzene), about 160 components in total. They are formed as a result of incomplete combustion of fuel in the engine.

Unburned hydrocarbons are one of the causes of white or blue smoke. This occurs when the ignition of the working mixture in the engine is delayed or at low temperatures in the combustion chamber.

Hydrocarbons are toxic and have an adverse effect on the human cardiovascular system. Hydrocarbon compounds exhaust gases, along with toxic properties, have a carcinogenic effect. Carcinogens are substances contributing to the emergence and development of malignant neoplasms.

The aromatic hydrocarbon benz-a-pyrene C 20 H 12 contained in the exhaust gases is distinguished by a special carcinogenic activity. gasoline engines and diesels. It dissolves well in oils, fats, human blood serum. Accumulating in the human body to dangerous concentrations, benz-a-pyrene stimulates the formation of malignant tumors.

Hydrocarbons under the action of ultraviolet radiation from the Sun react with nitrogen oxides, resulting in the formation of new toxic products - photooxidants, which are the basis of "smog".

Photooxidants are biologically active, have a harmful effect on living organisms, lead to an increase in lung and bronchial diseases in humans, destroy rubber products, accelerate the corrosion of metals, worsen visibility conditions.

Fifth group. It consists of aldehydes - organic compounds containing an aldehyde group -CHO associated with a hydrocarbon radical (CH 3, C 6 H 5 or others).

Exhaust gases contain mainly formaldehyde, acrolein and acetaldehyde. The largest amount of aldehydes is formed at idle and low loads. when combustion temperatures in the engine are low.

Formaldehyde HCHO is a colorless gas with bad smell, heavier than air, easily soluble in water. He irritates human mucous membranes, respiratory tract, affects the central nervous system. Causes the smell of exhaust gases, especially in diesel engines.

Acrolein CH 2 \u003d CH-CH \u003d O, or acrylic acid aldehyde, is a colorless toxic gas with the smell of burnt fats. It has an effect on the mucous membranes.

Acetic aldehyde CH 3 CHO is a gas with a pungent odor and a toxic effect on the human body.

Sixth group. Soot and other dispersed particles (engine wear products, aerosols, oils, soot, etc.) are released into it. Soot - black solid carbon particles formed during incomplete combustion and thermal decomposition of fuel hydrocarbons. It does not pose an immediate danger to human health, but may irritate the respiratory tract. By creating a smoky plume behind the vehicle, soot impairs visibility on the roads. The greatest harm of soot lies in the adsorption of benzo-a-pyrene on its surface., which in this case has a stronger negative effect on the human body than in its pure form.

Seventh group. It is a sulfur compound - inorganic gases such as sulfur dioxide, hydrogen sulfide, which appear in the exhaust gases of engines if fuel with a high sulfur content is used. Significantly more sulfur is present in diesel fuels compared to other types of fuels used in transport.

Domestic oil fields (especially in the eastern regions) are characterized by a high percentage of the presence of sulfur and sulfur compounds. Therefore, diesel fuel obtained from it using outdated technologies has a heavier fractional composition and, at the same time, is less purified from sulfur and paraffin compounds. According to European standards put into effect in 1996, the sulfur content in diesel fuel should not exceed 0.005 g/l, and according to the Russian standard - 1.7 g/l. The presence of sulfur increases the toxicity of diesel exhaust gases and is the cause of the appearance of harmful sulfur compounds in them.

Sulfur compounds have a pungent odor, are heavier than air, and dissolve in water. They have an irritating effect on the mucous membranes of the throat, nose, eyes of a person, can lead to a violation of carbohydrate and protein metabolism and inhibition of oxidative processes, at high concentrations (over 0.01%) - to poisoning of the body. Sulfur dioxide also has a detrimental effect on the plant world.

Eighth group. The components of this group - lead and its compounds - are found in exhaust gases carbureted cars only when using leaded gasoline, which contains an additive that increases octane number. It determines the engine's ability to run without detonation. The higher the octane number, the more resistant the gasoline is to knocking. detonation combustion the working mixture flows at supersonic speed, which is 100 times faster than normal. The operation of the engine with detonation is dangerous because the engine overheats, its power drops, and the service life is sharply reduced. Increasing the octane number of gasoline helps to reduce the possibility of detonation.

As an additive that increases the octane number, an antiknock agent is used - ethyl liquid R-9. Gasoline with the addition of ethyl liquid becomes leaded. The composition of the ethyl liquid includes the actual antiknock agent - tetraethyl lead Pb (C 2 H 5) 4, the scavenger - ethyl bromide (BrC 2 H 5) and α-monochloronaphthalene (C 10 H 7 Cl), the filler - B-70 gasoline, an antioxidant - paraoxydiphenylamine and dye. During the combustion of leaded gasoline, the scavenger helps to remove lead and its oxides from the combustion chamber, turning them into a vapor state. They, together with the exhaust gases, are released into the surrounding area and settle near the roads.

In roadside areas, approximately 50% of particulate lead emissions are immediately distributed to the adjacent surface. The rest is in the air in the form of aerosols for several hours, and then is also deposited on the ground near roads. The accumulation of lead in the roadside leads to pollution of ecosystems and makes nearby soils unsuitable for agricultural use. The addition of R-9 additive to gasoline makes it highly toxic. Different brands gasoline have different percentages of additives. To distinguish brands of leaded gasoline, they are colored by adding multi-colored dyes to the additive. Unleaded gasoline is supplied uncolored (Table 9).

In the developed world, the use of leaded gasoline is limited or has already been completely discontinued. In Russia, it is still widely used. However, the goal is to stop using it. Large industrial centers and resort areas are switching to the use of unleaded gasoline.

Ecosystems are negatively impacted not only by the considered components of engine exhaust gases, divided into eight groups, but also by hydrocarbon fuels, oils and lubricants themselves. Possessing a great ability to evaporate, especially when the temperature rises, vapors of fuels and oils spread in the air and adversely affect living organisms.

Accidental spills and intentional discharges of used oil directly onto the ground or into bodies of water occur at fuel and oil refueling sites. Vegetation does not grow in place of the oil spot for a long time. Oil products that have fallen into water bodies have a detrimental effect on their flora and fauna.

Published with some abbreviations according to the book of Pavlov E.I. Ecology of transport. Underlining and highlighting are mine.

Now, thanks to the media, the planet is under the close attention of the public, namely its saturation and pollution with car exhaust gases. With particular attention, people monitor and discuss such a by-product of widespread motorization, circulated in the press, as the "greenhouse effect" and harm exhaust gases diesel cars.

However, as is known traffic fumes, exhaust gases - discord, despite the fact that they are all dangerous for 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 upheavals, which on the one hand created an extremely difficult socio-economic environment, but greatly 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 the gradual tightening of emission standards harmful substances into the atmosphere, due to the increase in the number of cars, the results of this work, alas, are leveled.

If we segment the total mass of various vehicles currently present on the planet, the dirtiest remain, cars with this type of fuel exceeding nitrogen oxide are especially dangerous. 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 diesel engines, major German cities such as Stuttgart and Munich are currently discussing a ban on 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 gasoline models have a similar problem, as they increasingly use direct fuel injection systems, which result in the by-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 can be a source of a dangerous phenomenon, from Agriculture, to laser printers, fireplaces and, of course, cigarettes.

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 Federal Ministry environment Germany, 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 more and more economical 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)

An extremely hazardous by-product of combustion. 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 It has importance for the lives 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 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 engines internal combustion. Diesel vehicles considered the main source. The introduction of catalytic converters and diesel particulate filters continues to increase, so emissions will be markedly reduced, but this will only happen in the future.

City dwellers often talk about ecology, and mostly scold it. In principle, there are many reasons for this, but exhaust gases are especially often talked about. So, what exactly does the city breathe and what does the smell of exhaust gases hide in itself?

Often, exhaust gases are called all emissions into the urban atmosphere, including boilers, factories and other industrial enterprises. In fact, it is correct to call this term only transport emissions that appear as a result of fuel processing. They are also called waste gases. Exhaust gases are a product of internal combustion engines, and given the rapid growth in the number of vehicles over the past 50 years and, in particular, the increase in personal vehicles in cities, exhaust gases in the air of cities have settled down seriously and for a long time, and their number is only growing.

Now it is exhaust gases that are the main cause of air pollution in the city and constantly affect human health. So, we figured out the terminology, let's find out what exactly cars regularly deliver to our atmosphere, why it is dangerous and how to protect yourself if you smell exhaust gases in the apartment.

All cars emit carcinogens and toxic substances into the air. The composition of the exhaust gases of a car varies depending on the type of engine, gasoline or diesel, but the basic set remains the same.
So, the composition of automobile exhaust gases includes:

Component	Volume fraction in petrol engine, %	Volume fraction in diesel engine, %	Toxicity
Nitrogen	74–77	76–78	non-toxic
Oxygen	0,3–8	2–18	non-toxic
water vapor	3–5,5	0,5–4	non-toxic
Carbon dioxide	5–12	1–10	non-toxic
carbon monoxide	0,1–10	0,01–5	toxic
hydrocarbons	0,2–3	0,009–0,5	toxic
Aldehydes	0–2	0,001–0,009	toxic
sulphur dioxide	0–0,002	0–0,03	toxic
Soot, g/m3	0–0,04	0,1–1,1	toxic
Benzopyrene, g/m3	0,01–0,02	0–0,01	toxic

As you can see, the composition of exhaust gases is quite diverse, and most of the components are toxic. Now let's see what effect exhaust gases have on a person.

The effect of exhaust gases on the human body

Vehicle exhaust fumes can be harmful to health, and quite serious. First of all, carbon monoxide or carbon monoxide, which we have already mentioned, has no taste and smell, but at high concentration causes dizziness, headache, nausea, can lead to fainting.
Sulphurous gasoline and the sulfur oxide it creates is one of the causes of strong exhaust odors. The fact is that sulfur dioxide molecules have a very noticeable effect on olfactory receptors, so this smell is felt even at a low concentration, and a more concentrated “aroma” covers all other smells for a person’s nose, which can be confirmed by anyone who lit matches in the house. Leaded gasoline enriches the air with lead. The amount of such exhaust gases and the health damage they cause has made lead one of the most notorious toxic compounds in the atmosphere. Currently, such gasoline is no longer used as a fuel for cars, but for quite a long time its vapors filled all major cities. Hydrocarbons in car emissions are oxidized when exposed to sunlight and form toxic compounds with a pungent odor, which particularly affect the upper respiratory tract and lead to exacerbations of chronic diseases of the respiratory system.
The harm from car exhaust gases is largely explained by carcinogens - soot and benzopyrene, which contribute to the development of tumors, especially malignant ones.

Considering exhaust gases and the harm they bring, we must add about the effect of this chemical cocktail in its entirety: prolonged contact with exhaust gases leads to death, in particular from carbon monoxide poisoning. The greatest danger of these emissions is their quantity, prevalence and fine particle size, which allows the exhaust to pass through the natural barriers of the body and into the lungs. With constant exposure to exhaust gases on the body, immunodeficiency, bronchitis can develop, brain vessels, the nervous system and other organs suffer. In addition, most of the toxic substances that make up exhaust gases can interact with each other and with other components of the atmosphere, which contributes to the formation of smog.

Everyone who has taken a school course in botany knows that plants also breathe. And, like any breathing organism, they feel pollution from exhaust gases on themselves. The smallest particles of harmful compounds enter the body of the plant and poison it, therefore, very often in the city, located near big roads or parking lots, lawns and trees look sluggish, quickly turn yellow or die altogether.

Air pollution from exhaust gases has significantly affected the composition of atmospheric precipitation. It is thanks to the activity of transport that acid rains, colored fogs or snow of fifty shades of black appear. Naturally, due to precipitation, the air is somewhat purified, but all the collected dirt enters the soil, causing general pollution of the environment with exhaust gases. The same compounds and heavy metals spread further through the soil, getting into animal feed and cultivated crops, which means polluting not only nature, but also repeatedly humans. Of course, it would be superfluous to panic about this, but with such pollution of the atmosphere with exhaust gases, you should take care of your health.

How to protect yourself from exhaust gases

We get the greatest harm from exhaust gases while in traffic jams, where there is simply nowhere to run from automobile emissions. In such a situation, if there is no respirator or gas mask at hand, you still have to inhale the exhaust, but you can cover your nose and mouth with a handkerchief or scarf. This will not completely protect you from exhaust emissions, but it will at least smooth the situation somewhat. With constant exposure to exhaust, it is worth diversifying your menu with antioxidants found in berries, fruits, green vegetables and green tea, as well as seeds, and drinking more water, as it promotes detoxification. Such “doping” helps the body cope with the consequences of inhaling a chemical cocktail and maintains health.

Exhaust gases in the apartment are clearly unwanted guests, but they often penetrate our homes if there are roads or parking lots under them or near them. If there is no possibility or desire to move to the bosom of nature away from the roads, you can create safe zones in the house. To understand how to protect yourself from exhaust gases in an apartment, you need to determine the source of their appearance. In the vast majority of cases, exhausts penetrate through windows. In this case best solution will install sealed double-glazed windows, and carry out ventilation using high-quality

According to environmental studies, in large cities, almost 90% of air pollution comes from transport emissions. The biggest pollutants are diesel-powered vehicles. The type of gasoline burned also plays an important role. For example, sulphurous gasoline emits sulfur oxides into the atmosphere, and chlorine, bromine and lead. But the most common exhaust gas composition is as follows:

Nitrogen - 75%;
- oxygen - 0.3-8.0%;
- water - 3-5%;
- carbon dioxide - 0-16%;
- carbon monoxide - 0.1-5.0%;
- nitrogen oxides - 0.8%;
- hydrocarbons - 0.1-2.5%;
- aldehydes - up to 0.2%;
- soot - up to 0.04%;
- benzpyrene - 0.0005%.

Carbon monoxide

The product of incomplete combustion of gasoline or diesel fuel. This gas has no color, so a person cannot feel its presence in the atmosphere. This is its main danger. Carbon monoxide binds to hemoglobin and causes tissues and organs in the body. This leads to headache, dizziness, loss of consciousness and even death.

There are frequent cases when warming up the car in a closed or even open garage led to the death of the car owner. Odorless and colorless, carbon monoxide causes loss of consciousness and death.

nitrogen dioxide

Yellowish-brown gas with a pungent odor. It impairs visibility, gives the air a brownish tint. Very toxic, can cause bronchitis, significantly reduces the body's resistance to colds. Nitrogen dioxide has a particularly negative effect on people suffering from chronic respiratory diseases.

hydrocarbons

In the presence of nitrogen oxides and under the influence of the ultraviolet of the sun, hydrocarbons are oxidized, after which they form oxygen-containing toxic substances with a pungent odor, the so-called photochemical smog. Cyclic aromatic hydrocarbons are also found in tars and soot, they are the strongest carcinogens. Some of them are capable of causing mutations.

Formaldehyde

A colorless gas with an unpleasant and pungent odour. In large quantities, it irritates the respiratory tract and eyes. Toxic, damaging nervous system, has a mutagenic, allergenic and carcinogenic effect.

Dust and soot

Suspended particles, no larger than 10 microns. Can cause diseases of the respiratory system and mucous membranes. Soot is a carcinogen and can cause cancer.

During engine operation, unburned particles accumulate on the walls of the exhaust system. Under the influence of gas pressure, they are released into the atmosphere, polluting it.

Benzpyrene 3.4

One of the most dangerous substances that contains exhaust gases. It is a strong carcinogen, increases the likelihood of cancer.

Vehicle gases remain in the surface layer of the atmosphere, which makes it difficult to disperse them. Narrow streets and tall buildings also help trap toxic exhaust gases in the breathing zone of pedestrians. The composition of vehicle exhaust gases includes more than 200 components, while only a few of them are standardized (smoke, carbon and nitrogen oxides, hydrocarbons).[ ...]

The composition of exhaust gases depends on a number of factors: the type of engine (carburetor, diesel), its mode of operation and load, the technical condition and quality of the fuel (Tables 10.4, 10.5).[ ...]

Exhaust gases, in addition to hydrocarbons that make up the fuel, contain products of its incomplete combustion, such as acetylene, olefins and carbonyl compounds. The amount of VOCs in the exhaust gases depends on the operating conditions of the engine. A particularly large amount of harmful impurities enters the ambient air when the engine is idling - during short stops and at intersections.[ ...]

Exhaust gases include such toxic substances as carbon monoxide, nitrogen oxides, sulfur dioxide, lead compounds and various carcinogenic hydrocarbons.[ ...]

The composition of the exhaust gases of carburetor and diesel engines includes about 200 chemical compounds, of which the most toxic oxides of carbon, nitrogen, hydrocarbons, including polycyclic aromatic hydrocarbons (benz (a) pyrene, etc.). When burning 1 liter of gasoline, 200-400 mg of lead, which is part of the anti-knock additive, enters the air. Transport is also a source of dust arising from the destruction pavement and tire wear.[ ...]

Since the composition of the exhaust gases depends on the mixture of fuel and air and the timing of ignition, it will also depend on the nature of driving. For achievement highest power mixtures with 10-15% enrichment are required, while the most economical is the speed with a slightly lower fuel enrichment. For most engines Idling enriched mixtures are required, and combustion products are not completely ejected from the cylinder. When accelerating, the pressure in fuel system decreases and the fuel condenses on the collector walls. To prevent depletion fuel mixture a carburetor is used to supply more fuel when accelerating. Decreasing speed with a closed throttle increases the vacuum in the manifold, reduces air leakage and excessively saturates the mixture. With such fluctuations, emissions largely depend on the requirements for the engine (tab.[ ...]

The issue of exhaust gases and aerosols released into the air by automobile engines requires much more intensive study. In this direction, some data have already been obtained on the composition of exhaust gases, from which it follows that their composition changes under the influence of numerous factors, which include engine design, engine operation and maintenance, as well as the fuel used (Faith, 1954; Fitton, 1954) . At present, an intensive study of the effect of all components of exhaust gases in a chronic experiment on animals is planned.[ ...]

18

Colorless gas, odorless and tasteless. Density relative to air 0.967. Boiling point - 190°C. Solubility coefficient in water 0.2489 (20°), 0.02218 (30°), 0.02081 (38°), 0.02035 (40°). Weight of 1 liter of gas at 0°C and 760 mm Hg. Art. 1.25 g. Included in various gas mixtures, coke, shale, water, wood, blast-furnace gases, vehicle exhaust gases, etc.[ ...]

The exhaust gases of automobiles and other internal combustion engines are the main source of urban air pollution (up to 40% of all pollution in the United States). Many specialists tend to consider the problem of air pollution as a problem of its pollution with exhaust gases from various engines (cars, motor boats and ships, aircraft jet engines, etc.). The composition of these gases is very complex, because, in addition to hydrocarbons various classes, they contain toxic inorganic substances (oxides of nitrogen, carbon, sulfur compounds, halogens), as well as metals and organometallic compounds. The analysis of such compositions containing inorganic and organic compounds with a wide range of boiling points (C1-C12 hydrocarbons) encounters significant difficulties, and, as a rule, several analytical methods are used for its implementation. In particular, carbon oxide and dioxide are determined by IR spectroscopy, nitrogen oxides by chemiluminescence, and gas chromatography is used to detect hydrocarbons. It can also be used to analyze inorganic components of exhaust gases, and the sensitivity of the determination is about 10-4% for CO, 10-2% for NO, 3-10-4% for CO2 and 2-10"5% for hydrocarbons, but the analysis complex and time-consuming.[ ...]

The concentration of exhaust gases in the tunnel is affected by: 1) the intensity, composition and speed of the traffic flow; 2) length, configuration and depth of the tunnel; 3) the direction and speed of the prevailing winds in relation to the axis of the tunnel.[ ...]

In table. 12.1 shows the composition of the main impurities in the exhaust gases of gasoline and diesel internal combustion engines (ICE).[ ...]

It was mentioned above that the composition of the exhaust gases changes markedly with the change in the operating mode of the engine, so the reactor must be designed taking into account changes in concentrations. In addition, the reaction requires elevated temperatures, therefore, the reactor must provide a rapid rise in temperature, since water will condense in a cold reactor. Added to the technical difficulties necessary condition so that the reactor system operates for a long time without technical care. Unlike other devices in the car, in this case the motorist will not pay attention to the reactor system, which does not give him practical returns, and he may not receive real signals that the system has failed. In addition, monitor the effectiveness of the treatment system through regular checks and technical inspections much more difficult than achieving a certain average level of design reliability.[ ...]

10

The quantitative and qualitative composition of exhaust gases depends on the type and quality of fuel, type of engine, its characteristics, technical condition, qualifications of mechanics, provision of vehicle fleet with diagnostic equipment, etc.[ ...]

To determine nitrogen dioxide in the exhaust gases of internal combustion engines of automobiles and in the exhaust gases of silver regeneration baths, a non-flowing electrochemical cell with a long service life of 120 days is proposed. The working electrode is platinum or graphite, and the auxiliary is grade B coal. The absorption solution has a composition of 3% for KBr and 1% for H2304. lower limit analyzed concentration of nitrogen dioxide by this non-flowing cell 0.001 mg/l .[ ...]

In table. 3 shows the approximate composition of the exhaust gases of carburetor and diesel engines (I. L. Varshavsky, 1969).[ ...]

Significant air pollution occurs exhaust! automobile gases. They include a large range of toxic substances, the main of which are: CO, NOx - hydrocarbons, carcinogens. The pollutants of the air basin from road transport should also include rubber dust formed as a result of abrasion of tires.[ ...]

The technical condition of the engine. Big influence the composition of the exhaust gases is affected by the technical condition of the engine and, above all, the carburetor. Studies conducted by J-G. Manusadzhants (1971) showed that after the installation of new, properly adjusted carburetors on cars that previously had an increased content of carbon monoxide in exhaust gases (5-6%), the concentration of this gas decreased to 1.5% . Faulty carburetors after repair and adjustment also ensured a decrease in the content of carbon monoxide in the exhaust gases to 1.5-2%.[ ...]

A simple measure - adjusting engines can reduce the toxicity of exhaust gases by several times. Therefore, in the cities, control and measuring points are being created for diagnosing car engines. In the car fleet, on special running drums that replace the roadbed, the car is tested, during which the chemical composition of engine gases is measured under different operating modes. A machine with a large exhaust emission to the line should not be produced. According to data available in the literature, this measure alone can reduce air pollution by 3.2 times in 1980, and by 4 times by 2000.[ ...]

The scheme under consideration provides for a part of the thermal energy of the exhaust gases during the heating period to be used for heating purposes of the CS adjacent settlements, greenhouse and livestock farms. The integrated power plant at the compressor station includes many units, assemblies and equipment shown in the diagram in Fig. 1, which have shown high efficiency and have been successfully operated for a long time in various industries.[ ...]

In the conditions of Yuzhno-Sakhalinsk, where the main pollutants are vehicle exhaust gases and waste from thermal power plants, no special work has been carried out to influence them on individual objects of the plant world. In the course of work to determine the microelement composition of a number of plants, including meadow and weed grasses, some observations were made on the content of toxic microelements in the above-ground mass of plants within the city and beyond, as well as on reclaimed waste maps of the ash dump of the Yuzhno-Sakhalinskaya CHPP . The chemical composition depends both on the species and on the external conditions of existence, therefore, to determine lead, samples of the following plant species were taken: team hedgehog (Dactylis glomerata L.), creeping clover (Trifolium repens L.), Langsdorf reed grass (Calamagrostis langsdorffii (Link) Trin.), meadow bluegrass (Poa pratensis L.), pharmaceutical dandelion (Taraxacum officinale Web.) - within the city, on roadsides and for control - in places remote from anthropogenic impact.[ ...]

It has already been mentioned that the sun's rays can change the chemical composition of air pollutants. This is especially noticeable in the case of pollutants of the oxidizing type, when the sun's rays can lead to the formation of an irritating gas from a non-irritating one (Haagen-Smit a. Fox, 1954). Photochemical transformations of this type occur in the reaction between hydrocarbons contained in the air and nitrogen oxides, and the main source of both is the exhaust gases of vehicles. These photochemical reactions are of such great importance (for example, in Los Angeles) that great efforts are being made to solve this particular problem posed by automobile exhaust gases. The solution to this problem is approached from three different angles: a) by changing the fuel for engines; b) by changing the design of the engine; c) by changing the chemical composition of the exhaust gases after their formation in the engine.[ ...]

It may seem strange to you that there is no mention of carbon monoxide (carbon monoxide), which, as everyone knows, is part of the exhaust gases of a car. There are many people who die every year who have the habit of trying out an engine in a closed garage or lifting the windows of a car with a leak in its exhaust system. In high concentrations, carbon monoxide is certainly deadly: by combining with blood hemoglobin, it prevents the transfer of oxygen from the lungs to all organs of the body. But in the open air, in the vast majority of cases, the concentration of carbon monoxide is so low that it does not pose a danger to human health.[ ...]

Note that a significant amount of carbon monoxide enters the atmospheric air with the exhaust gases of cars and other vehicles equipped with carburettor internal combustion engines, the exhaust of which contains CO from 2 to 10% (large values ​​correspond to low speed modes) . In this regard, special attention is paid to the development of carburetors produced under the code name "Ozone" for cars"Zhiguli". Thanks to a number of technical innovations, this carburetor can significantly reduce the emission of substances harmful to the human body into the atmosphere with exhaust gases. On the recommendation of the Central Scientific Research Automobile and Automotive Institute, the Cascade device was used on the carburetor, which optimizes the composition of the fuel-air mixture, thereby making it possible not only to reduce the toxicity of emissions, but also to reduce specific consumption gasoline.[ ...]

Carbon monoxide is formed during the incomplete combustion of substances containing carbon. It is part of the gases released during the smelting and processing of ferrous and non-ferrous metals, exhaust gases of internal combustion engines, gases formed during blasting, etc.[ ...]

Modern methods of analysis allow, along with the age of individual ice layers, to determine the composition of the air during their formation, to monitor the growth of air pollution. So, in 1968 it was found that the level of lead oxide, which enters the air mainly with car exhaust gases, is already about 200 mg per 1 ton of ice. The authors of the book "Besieged eternal ice”, from which these figures are taken, comment on them as follows: “Ice, this silent witness to the evolution of the Earth’s climate, signals a huge danger. Will humanity listen to him? .[ ...]

Such studies also pave the way for the development of specific predictive models linking fuel composition and properties to exhaust emissions for vehicle families, starting with the earliest non-equipped vehicles. catalytic converters, up to cars latest models produced using the most the latest technologies. This relationship between properties, composition, and emissions is extremely complex, so such models allow fuel developers to find specific fuel composition limits where changes in fuel characteristics can have a measurable, quantifiable effect on exhaust emissions. These formulation limits will, of course, depend both on the type of vehicles available on the particular market and on the possibilities of fuel production. Thus, in this case, in order to understand the whole process, it is necessary to have a clear picture that characterizes both of these factors.[ ...]

Phenols are used for disinfection, as well as for the manufacture of adhesives and phenol-formaldehyde plastics. In addition, they are part of the exhaust gases of gasoline and diesel engines, are formed during the combustion and coking of wood and coal.[ ...]

Under the influence of emissions carried out by industrial enterprises, chemically active waste and residues from the main production, the composition of atmospheric air in cities changes significantly. It significantly increases the percentage of dust content, in addition, there are "traces" of substances that are not characteristic of the environment in its natural state. The increasing growth of vehicle exhaust gases contributes to the development of severe respiratory diseases. Emissions of harmful substances from vehicles and industrial enterprises cause increased air pollution with sulfur oxides, sulfates, carbon dioxide, carbon monoxide, nitrogen oxides, hydrogen sulfide, ammonia, acetone, formaldehyde, etc. The irritating effect of atmospheric pollution is manifested by a non-specific reaction of the body. In acute cases of high air pollution, irritation, conjunctiva, cough, increased salivation, spasm of the glottis and some other symptoms are noted. With chronic air pollution, there is a known variability of the listed symptoms and their less pronounced character. Air pollution in cities is the reason that increases the resistance to air flow in the respiratory tract.[ ...]

Control over the state of the air in the Federal Republic of Germany is carried out by a network of posts and nine permanent stations (Munich) that monitor the content of harmful gases and dust in the atmosphere. The measurement data are sent to a processing center equipped with a computer for compiling required characteristics air pollution and their ¡classification.[ ...]

Road transport is not one of the leading sources of sulfur dioxide in the atmosphere. In the book by I. L. Varshavsky, R. V. Malov “How to neutralize the exhaust gases of a car” (1968), the issue of sulfur dioxide as an emission from a car engine is not considered at all. This position is consistent with the results of studies in 1974-1975 of air on the highways of busy motor traffic in Leningrad, where isolated cases of a slight excess of the permissible concentrations of sulfur dioxide were observed (G. V. Novikov et al., 1975). However, according to the United States (VN Smelyakov, 1969), the annual emission of sulfur oxides by cars in this country reaches 1 million tons, i.e., it is commensurate with the emission of particulate matter. In England, in 1954, according to the data of Pchop (1956), the emission of sulfur dioxide by car engines amounted to 20,000 tons. and 0.02% - diesel. These materials convince of the expediency of controlling anhydride concentrations on heavy traffic routes.[ ...]

In addition, this knowledge and this approach can be applied to newly developed engine technologies. As shown in fig. 1, it is expected that the future direction of work to minimize exhaust emissions traditional engines will move towards fully optimized systems, covering vehicle, engine and fuel. A key factor in this process will be knowing how to properly formulate specific fuels to make them suitable for such systems.[ ...]

As examples of the practical application of promising Pb, Sn, and Te laser diodes, two projects developed by the American firm Texas Instruments (Dallas) can be cited. In the first of these, a compact device (weighing no more than 4.5 kg) based on a tunable laser diode is being developed for monitoring industrial emissions from pipes for the content of 302, NO2 and other gases. The second project aims to create handy device for monitoring the exhaust gases of cars for the content of CO, CO2, residues of unburned hydrocarbons and sulfur-containing gases. The constructed layouts are matrices of a number of laser bottoms, each tuned to a specific gas and optically connected by similar matrices of photodetectors. The instrument must be placed directly into the exhaust jet. Difficulties are associated with the development of a convenient cooler necessary to provide continuous laser radiation. This prnbor is created as a mass control tool in connection with the project under development. state standard USA on the permissible composition of exhaust gases. Both devices are based on the absorption method.[ ...]

While fuel sulfur management and alternative fuel selection have the potential to provide indirect reductions in vehicle emissions, from the oil company's perspective, the main factor to consider when developing fuels with low level harmful emissions, is the possibility of direct influence on exhaust gas emissions of such fuel properties as hydrocarbon composition, volatility, density, cetane number, etc., as well as oxygen-containing compounds (oxidizers) or biofuels included in the fuel composition. This section addresses the first question. The latter topic is discussed in more detail in the accompanying article published in the same journal.[ ...]

The nitrogen and sulfur cycles are increasingly affected by industrial air pollution. Nitrogen oxides (NO and N02) and sulfur oxides (50 g) appear during these cycles, but only as intermediate stages and are present in most habitats in very low concentrations. The burning of fossil fuels has greatly increased the content of volatile oxides in the air, especially in cities; at such a concentration, they already become dangerous for the biotic components of ecosystems. In 1966, these oxides accounted for about a third of the total (125 million tons) of industrial emissions in the United States. The main source of GOD is coal-fired thermal power plants, and the main source of NO2 is car motors. L), and nitrogen oxides are harmful, getting into the respiratory tract of higher animals and humans. As a result chemical reactions of these gases with other pollutants, the harmful effect of both is aggravated (a kind of synergism is noted). The development of new types of internal combustion engines, the purification of fuel from sulfur and the transition from thermal to nuclear power plants will eliminate these serious disturbances in the nitrogen and sulfur cycles. Parenthetically, such changes in the way humans produce energy will raise other problems that need to be thought about in advance (see ch. 16).[ ...]

This circumstance predetermines the following argument in favor of domestic hydrogen energy. It consists in the need for a global approach to solving similar problems. The trend towards the general integration of the trade and economic system today is such that it requires an analysis of the world market for the overwhelming range of goods and services. Under these conditions, Russia can no longer be pulled out of global industrial, trade and economic ties. It is impossible not to take into account, without incurring large material and moral losses, with increasingly stringent environmental requirements, enshrined in national and international legislation. The Clean Air Act adopted by the US Congress, the above-mentioned tightening on the chemical composition of exhaust gases from air and land vehicles in Western Europe and other regions of the planet, as well as a number of other legislative measures, essentially serve as the basis for the Global Environmental Code. There is a need to create a national concept for the use of hydrogen in the country's fuel base as an environmentally friendly fuel for air and ground transport. Such a concept and a corresponding national program can be developed as part of the conversion of defense industries.[ ...]

When studying environmental pollution from emissions of an industrial enterprise, usually only those chemicals are taken into account, which, on the basis of technological process can be considered a priority in terms of gross emissions into the atmospheric air or into wastewater. Meanwhile, a significant part of the initial and final products of production has a fairly high reactivity. Therefore, there is reason to believe that these compounds interact not only at the stage of the technological process. The possibility of such interaction in the air cannot be ruled out. industrial premises, from where the newly formed products enter the atmospheric air as fugitive emissions. New chemicals can be produced as a result of chemical and photochemical reactions in polluted air, as well as in water and soil. An example is the formation of new chemicals from the products of incomplete combustion of fuel, which is part of the exhaust gases of cars. At present, the pathways of photochemical oxidation of these products have been sufficiently studied. The possibility of atmospheric air pollution by qualitatively new chemicals not specified in the technological regulations of the enterprises under study has been proved.