Consider the main sources of air pollution. Currently, there are two large groups: anthropogenic and natural. Each of them has its own distinctive features and characteristics.
Natural species
Natural sources of air pollution are those groups that have a plant, mineral or microbiological nature. What can be cited as an example? These are plant pollen, animal excrement, dust, products of volcanic eruptions. It is not possible for a person to influence these sources of air pollution. The only thing in the power of mankind is to use optimal methods to reduce the negative impact of them on public health.
Artificial species
Anthropogenic sources of air pollution are human waste products that enter the earth's atmosphere. There is a division into several groups, each of which deserves detailed consideration and study.
Traffic pollutants
Due to the significant deterioration of the environmental situation on our planet, it is necessary to look for alternative energy sources, during the combustion of which carbon oxides will not be emitted in large quantities. A car is a source of air pollution. According to the results of sociological studies, it was found that in some countries there are 1-2 vehicles per family. Millions of vehicles today move along the streets of large cities, and the air increases the content of toxic exhaust gases. In Russian cities, automobile CO / CH emissions into the atmosphere have long exceeded emissions from the operation of huge production workshops. The total capacity of automobile engines in our country is much higher than the installed capacity of all thermal power plants in the country. Such sources of air pollution are a serious public health hazard.
Automotive exhaust contains many different substances. They contain hydrocarbons - not burnt or not completely burnt parts of the fuel, the amount of which increases significantly when the engine is running at low speeds.
Serious danger is represented by those periods of time when the car starts to move sharply. When the driver presses the gas pedal, ten times more unburned chemical compounds are released into the atmosphere than during the operation of the engine in standard mode.
These artificial sources of air pollution negatively affect the mental state of a person.
Harm from a gasoline engine
This is a special type of reciprocating internal combustion engine in which the ignition of the air and fuel mixture in the cylinders is forced by an electric spark. In gasoline engines, gasoline is used as fuel.
The source of air pollution are hydrocarbons that make up this type of fuel.
A four-stroke engine is a reciprocating internal combustion engine in which the working process in each of the cylinders takes place over two full revolutions of the crankshaft, that is, over four piston strokes, called strokes.
Exhaust composition
Let us consider in more detail these sources of air pollution. The exhaust gases of an engine running on high-quality gasoline contain about 2.7% carbon monoxide. In the case of a decrease in speed, this figure increases to 3.9%, and at low speeds it reaches 6.9%. Carbon monoxide during the formation of chemical compounds with hemoglobin in the blood, negatively affects the process of oxygen transfer to different tissues of the body. Aldehydes are present in the exhaust gas, which have an unpleasant pungent odor causing an allergic reaction.
A serious source of atmospheric pollution is unsaturated ethylene hydrocarbons: hexenes, pentenes. These organic compounds contained in exhaust gases inhibit the central nervous system of a person, cause attacks of aggression and irritability.
The maximum number of different resins and soot is formed if there are serious malfunctions in a running gasoline engine.
These sources of air pollution are especially dangerous at the moment when the driver increases the operation of the gasoline engine, while reducing the air-fuel ratio, trying to create a “rich gasoline mixture”. In such situations, the tail stretches behind the vehicle from smoke, in which there is a significant amount of polycyclic hydrocarbons, for example benzopyrene.
If natural sources of atmospheric pollution appear periodically, then exhaust gases have a permanent negative effect on the Earth, systematically destroying its atmosphere.
The impact of CO / CH on the atmosphere and human health
We have already identified some sources and consequences. Air pollution leads to the destruction of green plants, the emergence of many genetic diseases. The whole blame is exhaust fumes. Let us dwell on this issue in more detail.
Scientists were able to find out that when a significant amount of exhaust gas enters the earth’s atmosphere, serious problems arise with the development of the fetus in the womb, both in late and early pregnancy.
When settlements are located near large highways along which vehicles with gasoline engines move, women often have babies with serious health problems.
It is interesting
American scientists in the course of research found that exhaust gases cause significant damage to neurons that affect the functioning of the brain, causing a decrease in memory. They lead to inflammation, which is associated with premature aging and the development of Alzheimer's disease. Particles of unburned hydrocarbons in the exhaust gases are small in size, so they are not captured by the vehicle filtration system. Unfortunately, scientists have not yet been able to find an effective way to protect the population from the negative effects of gasoline fuel combustion products.
Alternative engine options
Since the main sources of atmospheric pollution discussed above are a serious threat to humanity, scientists have long worked on the creation of an electric motor that does not involve the use of gasoline in the process of its functioning. An electric motor is an installation in which the conversion of electrical energy to mechanical work takes place, and heat is also released. Such a system consists of two parts: a fixed stator, a rotating rotor.
Many engineers refer to electric motors as vehicles with zero emissions of carbon dioxide. Its efficiency reaches 95% (for gasoline this indicator does not exceed 60%). Among the advantages of an electric motor, we highlight the insignificant costs of maintenance and operation of such vehicles.
After analyzing what are the sources of air pollution, how they are related to the composition of the fuel, we can conclude that electric cars are the best option for the environment.
There is no need to put mechanical brakes in them, and it is precisely when the vehicle stops that a significant amount of exhaust gas is released into the atmosphere.
Environmental aspects of the electric motor
In the manufacture of batteries, certain chemicals are used to process them. For example, chemical sources of air pollution such as hexafluoride (SF6) are 20,000 times more dangerous to global warming than carbon dioxide. But this substance, used in electric motors, is much smaller in volume, and therefore, electric motors can rightfully be considered environmentally friendly species.
To understand what is the difference between gasoline cars and electric cars, we will carry out comparative calculations.
Since the main sources of air pollution are associated with gasoline vehicles, suppose 3.785 liters of liquid fuel are needed to move a car 64 kilometers. To travel this path with an electric motor vehicle, 10 kWh of energy is required. In the process of combustion of 3.785 liters of gasoline, 8.887 grams of carbon dioxide are released into the earth's atmosphere. During the generation of alternative 10 kWh of electric energy, including the process of extraction, production, transmission and combustion, 900 g of CO 2 for hydroelectric power plants, 550 g for solar plants, 150 g for nuclear power are generated.
Electric cars do not have a negative impact on the human nervous system, do not interfere with living organisms to fully breathe, enjoy clean air.
When thinking over technologies for processing used electric batteries, these types of engines will be the best option for improving the environmental situation on Earth.
Industrial emissions
Analyzing the main sources of atmospheric pollution, it is necessary to dwell on a variety of technological processes necessary to provide the population with chemicals, clothing, food, household appliances, thermal energy. Currently, the share of industrial emissions into the atmosphere is reduced, since large enterprises are installing efficient gas capture systems. In our country, industrial atmospheric emissions are regulated on a legislative basis, which also helps to reduce harmful chemical emissions.
Household pollutants
This group includes compounds that are formed during the processing of various household waste, as well as enter the earth's atmosphere in the combustion process. Their share in the volume is much less than emissions from transport, the functioning of industrial enterprises.
Classification Options
If the students are asked the question: “What are the sources of air pollution”, when they answer it, they use the division of such substances into several groups. Consider some of the criteria used for this classification:
- In composition. Mechanical impurities are emitted, such as dust obtained during the combustion of solid fuel compounds, the manufacture of cement. This also includes soot, tire components rubbing against the road surface.
- Chemical pollutants in a gaseous or solid state contribute to the occurrence of processes whose products adversely affect the atmosphere. Among them: ammonia, nitrogen oxides, sulfur dioxide, aldehydes, ketones.
- Radioactive sources include isotopes and radiation.
- Biological airborne contaminants are fungal, microbial, and viral organisms.
Conclusion
Earth's atmosphere is currently being attacked by a variety of pollutants. By their nature, they can be of natural, artificial origin. Let us dwell on the processes associated with the eruption of volcanoes. In the bowels of the earth are processes that result in the formation of a variety of compounds of organic and inorganic nature.
During the volcanic eruption, in addition to dust and other solid components, many compounds enter the atmosphere: hydrogen sulfide, sulfur oxides, sulfates. These pollutants are not predictable, and therefore, a person can not influence them.
Recently, issues related to the reduction of negative emissions into the Earth's atmosphere have received special attention around the world. There are many international organizations whose main goal is to search for optimal methods and means of protecting flora and fauna from chemical, industrial, and natural pollution.
Among the effective measures that have a positive effect on reducing emissions of carbon monoxide, sulfur compounds, nitrogen, we can name a gradual transition to high-quality fuel, as well as a partial rejection of gasoline engines. Many large automobile concerns are developing electric and hydrogen engines that do not release harmful chemicals into the atmosphere.