THE IMPACT OF VEHICLES ON THE ENVIRONMENT
Associate Professor, Candidate of Technical Sciences. Eurasian National University. L.N. Gumilev
Mukabylov Yerdos Omirgalyuly
The negative effect of thermal machines on the environment is due to the action of various factors. First, the combustion of fuel uses oxygen from the atmosphere, so that the oxygen content in the air gradually decreases. Secondly, the combustion of fuel is accompanied by the release of carbon dioxide into the atmosphere. Thirdly, when coal and oil are burned, the atmosphere is polluted with nitrogen and sulfur compounds, which are harmful to human health. Then automobile engines annually emit two to three tons of lead into the atmosphere.
Emissions of harmful substances into the atmosphere are not the only side of the impact of energy on nature. According to the laws of thermodynamics, the production of electrical and mechanical energy in principle can not be carried out without the release of significant amounts of heat into the environment. This can not but lead to a gradual increase in the average temperature on the ground, called "thermal pollution". This effect is exacerbated by the fact that the combustion of a huge amount of fuel increases the concentration of carbon dioxide in the earth's atmosphere. At a high concentration of carbon dioxide, the atmosphere does not pass the thermal radiation of the Earth's surface heated by the Sun, which leads to a "greenhouse effect". As a result of the described processes, the average temperature on Earth has been steadily increasing over the past decades. This threatens global warming with undesirable consequences, including melting glaciers and raising the level of the world's oceans.
A serious problem facing humanity is the "ecological crisis". The enormous scale of energy conversion has already begun to have a "planetary" impact on the Earth's climate and composition of the atmosphere.
In addition, when fuel is burned in thermal engines, atmospheric oxygen is consumed (in the most developed countries thermal engines already consume more oxygen than are produced by all plants growing in these countries) and many harmful substances are formed that pollute the atmosphere.
Thermal machines not only burn oxygen, but also throw into the atmosphere equivalent amounts of carbon monoxide (carbon dioxide). Combustion of fuel in the furnaces of industrial enterprises and thermal power plants is almost never complete, so air pollution with fly ash and soot flakes occurs. Worldwide, conventional power plants emit more than 200 million tons of ash and more than 60 million tons of sulfur oxide annually.
Toxic emissions of internal combustion engines (ICE) are spent and crankcase gases, fumes from the carburetor and fuel tank. Most of the toxic impurities enter the atmosphere with the exhaust gases of the ICE. With crankcase gases and fumes of fuel, about 45% of the hydrocarbons from their total release enter the atmosphere. In addition to industry, air is also polluted by various types of transport, especially motor vehicles. Inhabitants of big cities are suffocated by the exhaust gases of automobile engines.
Thermal machines are widely used in production and in everyday life. By railways, convoys are powered by powerful diesel locomotives, along waterways - by motor ships. Millions of cars with internal combustion engines transport cargo and passengers. Piston, turboprop and turbojet engines are equipped with airplanes and helicopters. With the help of rocket engines launches of artificial satellites, spacecraft and stations. Internal combustion engines are the basis for mechanization of production processes in agriculture. They are installed on tractors, combines, self propelled chassis, pumping stations. 
Throughout the XX century, the production of cars has grown rapidly.
This distribution of cars was mainly due to the qualities of the engine installed on it. With a relatively small mass, it develops enough power for fast driving, while consuming not much fuel. One refueling is enough for 400-500 km.
Everything was fine, until there were so many cars. In the capitals of developed countries, there are more than 300 cars per thousand people. Obviously, with so many cars, the light smoke emanating from the exhaust pipes pollutes the surrounding air so much that it causes significant damage to the health of people and nature. Observations showed that in houses located near a large road (up to 10 m), residents suffer from cancer 3-4 times more often than in houses that are 50 m away from the road. Transport also poisons water bodies, soil and plants.
Among the many different gases and chemical compounds emitted by the car, there are toxic substances. At present, road transport accounts for more than half of all harmful emissions to the environment, which are the main source of atmospheric pollution, especially in large cities.
In the engine cylinders, oxidation of finely dispersed and evaporated fuel with air oxygen takes place with the formation of heat, carbon dioxide and water. For the thousandths of a second allocated to this process with each stroke of the engine, part of the fuel does not have time to burn. The products of its incomplete combustion are thrown out of the exhaust pipe into the atmosphere.
The most prominent is carbon monoxide and various carbons, among which benzopyrene is a particular danger - a substance that contributes to the onset of cancer. In addition, nitrogen, which ispart of the air, reacts with oxygen at high temperatures and pressure developed in engine cylinders, forming dangerous oxides.
It turned out that the pressure on low-octane gasoline, even a small amount of so-called ethyl liquid, allows it to be used in engines without fear of detonation. This way is both simpler and cheaper and has been chosen almost everywhere. Gasoline with an additive of ethyl liquid was called leaded. But the ethyl liquid contains lead and compounds that promote its conversion to volatile salts, which are carried away with exhaust gases, which resulted in a large accumulation of lead in the environment and affected the health of the population. About 70% of the lead added to gasoline with ethyl liquid gets into the atmosphere with the exhaust gases, of which 30% settles on the ground immediately, and 40% remains in the atmosphere. One medium-duty truck produces 2.5 - 3 kg of lead per year. The concentration of lead in the air depends on the content of lead in gasoline.
This leads to the development of a wide range of diseases (bronchitis, pneumonia, bronchial asthma, heart failure, strokes, stomach ulcers) and increased mortality of people with weakened immunity. It is especially difficult for children (bronchitis, bronchial asthma, coughing, neonatal disorders of the body's genes and incurable diseases develop), as a result, the infant mortality rate increases by 10% per year.
The existing legislation does not allow to restrict the importation of old cars with low performance characteristics into the country, and the number of foreign cars with a long service life that do not meet the standards of state standards.
Therefore, many countries since the 80's. XX century began to move to the use of unleaded petrol, and the use of leaded declined sharply. In some European countries and the largest Russian cities, it is now generally banned. 
It became obvious: in order to stop pollution of the environment, it is necessary to introduce laws that limit the release of harmful substances. In European countries, the maximum permissible emission standards were established for various categories of vehicles.
The already existing engines are being improved, new ones are being created, which ensure more complete combustion of fuel. Carburet mixture is replaced by fuel injection, electronics are widely introduced.
This, of course, significantly reduces the toxicity of exhaust gases, but to reduce it to a safe yet fails. We have harmful substances coming out of the engine's cylinders, liquidate already in the exhaust system. For this, catalytic converters are used. But their use is associated with certain difficulties, since the exhaust gases pass through the exhaust system at a higher speed; and the neutralizers, which are installed under the bottom of the car, are subjected to significant external mechanical and thermal effects.
In modern neutralizers, platinum, palladium and rhodium are used as catalysts. These are very expensive metals, and although they are not spent much, the cost of the device is high.
When using neutralizers, you can refuel the car only with unleaded petrol, otherwise the neutralizer will become unusable, and the fuel consumption will increase. More stringent requirements are imposed on power and ignition devices, on their design and adjustment. In this regard, the car becomes more expensive. So, in modern foreign cars on the neutralization system and electronic devices account for 10-12% of the total cost. Despite this, automakers around the world are switching to equipping their products with neutralizers, as this ensures a 80-90% reduction in emissions of harmful substances.
The toxicity of the exhaust gases is strongly influenced by the grade of fuel used and its quality. At present, the production of gasoline without lead additives is increasing, in diesel fuel sulfur content is limited, fuel from oil is replaced by a more "clean" compressed natural gas. You can use as fuel and hydrogen, providing a very clean exhaust. However, it is not yet possible to create cheap and safe systems of hydrogen generation and storage on board the car.
Of considerable interest are electric motors that use rechargeable batteries and electrochemical generators. Electric cars are highly adaptable to variable modes of urban traffic, easy maintenance, and most importantly - ecological purity. However, they do not yet find wide practical application. Firstly, there are no reliable, lightweight and sufficiently energy-intensive batteries. Secondly, the transfer of the car park to power from electrochemical batteries will lead to the expenditure of a huge amount of electricity for their recharging, a large part of which is generated in power plants when fossil fuels are burned. So in this case, air pollution will not occur from cars, but from power plants. Due to the high cost and slowdown, electric vehicles powered by solar panels have not become customary.
High-octane, stable in composition gas fuel mixes well with air and evenly distributes along the engine cylinders, contributing to a more complete combustion of the working mixture. The total emission of toxic substances in cars running on liquefied gas is much less than for cars with gasoline engines. When the engine is running on gas, a more complete combustion of the mixture takes place. And this leads to a decrease in toxicity of exhaust gases, reduction of carbon formation and oil consumption, increase of the motor resource. In addition, liquefied gas is cheaper than gasoline. 
Of great importance is the daily control of motor vehicles. All auto-farms are obliged to monitor the serviceability of the cars produced on the line. With a well-running engine, the exhaust gas of carbon monoxide should not be more than the allowable rate.
The Regulation on the "State Automobile Inspection" entrusted it with monitoring the implementation of measures to protect the environment from the harmful effects of motor vehicles.
The accepted standard for toxicity provides for further tightening of the norm: for carbon monoxide-by 35%, for hydrocarbons-by 12%, for nitrogen oxides-by 21%.
The plants introduced control and regulation of cars for the toxicity and smoke of exhaust gases.
New traffic control systems have been developed that minimize the possibility of traffic jams, because, stopping and then picking up speed, the car emits several times more harmful substances than with even traffic.
Motorways have been built to bypass cities that have accepted the entire flow of transit transport, which used to stretch along the city streets with an endless stream. The intensity of traffic decreased drastically, the noise decreased, the air became purer.
The growth of the automobile fleet generated the problem of recycling cars unsuitable for further operation. In order to avoid cluttering cities, it was necessary to create a whole network of enterprises for the development of old cars, sorting and sale of still suitable parts for use, processing of metal scrap. Unused waste is crushed, ground and sent to landfills.
Thus, when designing new cars, it is necessary to think about how to dispose of their residues, to exclude the use of materials that, after getting to landfills, will pollute the environment.
The absorption method of gas purification carried out in the absorber plants is the simplest and gives a high degree of purification, but requires bulky equipment and cleaning of the absorbing liquid. It is based on chemical reactions between a gas, for example, sulfur dioxide and an absorbing suspension (alkaline solution: limestone, ammonia, lime). In this method, gaseous harmful impurities are deposited on the surface of a solid porous body (adsorbent). The latter can be extracted by desorption when heated by water vapor.
The way of oxidation of combustible carbonaceous harmful substances in the air consists in burning in a flame and the formation of carbon dioxide and water.
The method of thermal oxidation - in heating and feeding into a fire burner.
Catalytic oxidation using solid catalysts is that sulfurous anhydride passes through the catalyst in the form of manganese compounds or sulfuric acid.
Reducers (hydrogen, ammonia, hydrocarbons, carbon monoxide) are used to purify gases by catalysis using reduction and decomposition reactions. Neutralization of nitrogen oxides is achieved by using methane followed by the use of alumina to neutralize the second stage of carbon monoxide produced.
A sorption-catalytic method for purifying highly toxic substances at temperatures below the catalysis temperature is promising
The adsorption-oxidation method also appears promising. It consists in the physical adsorption of small amounts of harmful components, followed by the blowing out of adsorbed matter by a special gas stream into the thermocatalytic or thermal afterburning reactor. In large cities, special urban planning measures are used to reduce the harmful effect of air pollution on people: zone building of residential areas, when low buildings are close to the road, then high and under their protection are children's and medical institutions; transport interchanges without intersections, landscaping. 
In all countries of the world with developed industry work is underway aimed at reducing and eliminating the effects of air pollution. The main efforts are aimed at preventing emissions of pollutants into the atmosphere. At all operating and new heating plants and thermal power plants, gas cleaning and dust-collecting equipment is installed. Measures are being taken to rationally locate thermal power plants. One of the areas related to environmental protection is the increase in energy efficiency, the struggle for its economy.
To reduce the negative consequences of the operation of thermal engines, they operate in two directions: on the one hand, they improve these engines, increasing their efficiency and reducing the emission of harmful substances, on the other hand they use energy-saving technologies. In countries where these technologies are developed and applied, energy consumption for the production of the same products is several times lower than in countries that are only now beginning to pay attention to energy-saving technologies.
Thus, it can not be said that no attention is paid to the issue of transport pollution. More and more ordinary trains are being replaced by electric locomotives, vehicles are being developed and already produced on batteries, at modern rates of progress one can hope that soon there will be ecologically clean aircraft and rocket engines. Governments make decisions against pollution of the planet. This is evidenced by the adopted declaration.
Conservation of nature is the task of our century, a problem that has become social. Again and again we hear about the danger that threatens the environment, but still many of us consider them an unpleasant, but inevitable, generation of civilization and believe that we will have time to cope with all the difficulties that have been revealed.
1. Lukanin. V.N., Trofimenko Yu.V. Industrial and Transport Ecology: Textbook for universities. Ed: Lukanin. V.N. M: High School, 2001.
2. Upushev E.M. Ecology, natute and economics: Textbook Almaty ―Gylym‖, 2002.
3. Vorobyev A.E. Bases of nature use: ecological, economic and legal aspects: Textbook allowance A.E. Vorobyev. Ed. Prof. Dyechenko. M: Fenix, 2007.
4. Environment and economics of nature use: Textbook for the universities. Ed. Prof. Gurisova E.V., Prof. Lokaptina V.N. M: Unity-Dana, 2002.
5. Lukanin V.N., Buslayev A.P., Yashina M.V. Vehicle streams and environment-2: Textbook allowance for the universities. Ed. Lukanina V.N. M: Infra-M, 2001.