IN modern world it is generally accepted that the exhaust gases from engines internal combustion do the biggest damage environment... Recently, however, conflicting opinions of experts about the influence of these gases have been increasingly heard. In our usual understanding, only machines harm nature, leaving generators and installations for heating, water supply and other needs in the background. According to a study by the European Journal of Medicine, car exhaust kills about 40,000 people every year.
The latest discoveries of scientists have confirmed the fact that about 6% of all deaths are associated with a Special risk group are children and the elderly, whose body cannot quickly clear itself of microscopic fuel molecules. Based on all this, the fact that exhaust gases can be harmless is questioned a lot. Even a novice driver knows that it is deadly to stay indoors with the engine running.
First carbon monoxide:
1) In case of short-term poisoning, irritation of the mucous membranes of the eyes, nose and throat will begin. Further exposure will result in vomiting and, most likely, loss of consciousness. For patients with asthma and emphysema, such poisoning may be the last.
2) Sleepiness, resulting fatigue and loss of consciousness are also small doses for a long time.
3) Blurred vision, worsening dizziness clearly indicate that the central nervous system is damaged.
Temperature exhaust gases is the root cause of all harm done. The fact is that the higher the temperature, the faster the combustion products are formed, which leads to an increase in the concentration of harmful substances during the exhaust. Quite often, doctors diagnose hypoxia in drivers who are on the road most of the time. Among them are truckers, taxi drivers, carriers and many others.
But everything is not as scary as it might seem. It is enough just to follow these tips, and it will save health for you and your loved ones:
1) inside the garage or near the home territory, try to leave the car in working order as little as possible;
2) buy quality fuel;
and you live in the private sector, then when installing the fence, we recommend making a small gap between the ground and the beginning of the canvas. Since the exhaust gases are heavier than air, they will escape into these gaps. If possible, experts recommend making one side of the fence “transparent”, which will speed up the ventilation of heavy gases;
4) Install various diesel generators as far as possible from living quarters. Develop a system to evacuate gases from your area, even in strong winds. It is better to spend a few extra thousand than to become asthmatic in 4-5 years.
Remember that any fuel and its vapors are hazardous to health, even outside car engines or generators.
A small educational program for those who like to breathe from the exhaust pipe.
The exhaust gases of the internal combustion engine contain about 200 components. The period of their existence lasts from several minutes to 4 -5 years. According to their 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, giving off 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 disrupted, oxygen starvation appears and a malfunction of all body systems occurs.
Car drivers are often prone to carbon monoxide poisoning vehicle when spending the night in a 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's susceptibility. Mild poisoning causes throbbing in the head, darkening in 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 occurs.
Third group. It contains nitrogen oxides, mainly NO - nitrogen oxide and NO 2 - nitrogen dioxide. These are gases generated 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.
It is readily oxidized by atmospheric oxygen and forms nitrogen dioxide. Under normal atmospheric conditions, NO is completely converted into NO 2 -gase of a brown color with a characteristic odor. It is heavier than air, therefore it gathers in depressions, ditches and is a great danger when maintenance Vehicle.
For the human body, nitrogen oxides are even more harmful than carbon monoxide. The general nature of the impact varies with the content of various nitrogen oxides. When nitrogen dioxide comes into contact with a moist surface (mucous membranes of the eyes, nose, bronchi), nitric and nitrous acids are formed, irritating the mucous membranes and affecting 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 expect negative consequences. With prolonged exposure to nitrogen oxides in concentrations exceeding the norm, people get sick with chronic bronchitis, inflammation of the mucous membrane of the gastrointestinal tract, suffer from heart weakness, as well as nervous disorders.
The 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 methaemoglobin, which leads to impaired cardiac activity.
Nitrogen oxides also have a negative effect on vegetation, forming solutions of nitric and nitrous acids on leaf plates. This property is also responsible for the effect of nitrogen oxides on building materials and metal structures. In addition, they participate in the photochemical reaction of smog formation.
Fourth group. This group, the most numerous in composition, 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 adversely affect the human cardiovascular system. Hydrocarbon compounds of exhaust gases, along with toxic properties, have a carcinogenic effect. Carcinogens are substances that contribute to the onset and development of malignant neoplasms.
The aromatic hydrocarbon benz-a-pyrene С 20 H 12, contained in the exhaust gases, has 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.
Under the influence of ultraviolet radiation from the Sun, hydrocarbons 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 metal corrosion, and worsen visibility.
Fifth group. It is made up of aldehydes - organic compounds containing an aldehyde group -CHO linked to a hydrocarbon radical (CH 3, C 6 H 5, or others).
The exhaust gases contain mainly formaldehyde, acrolein and acetaldehyde. The largest amount of aldehydes is formed on modes idle move and small loadswhen the combustion temperatures in the engine are low.
Formaldehyde НСНО is a colorless gas with unpleasant odor, heavier than air, easily soluble in water. It irritates human mucous membranes, respiratory tract, affects the central nervous system and 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 poisonous gas with the smell of burnt fat. Has an effect on mucous membranes.
Acetic aldehyde CH 3 CHO is a gas with a pungent odor and toxic effect on the human body.
Sixth group. Soot and other dispersed particles (engine wear products, aerosols, oils, carbon deposits, 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 health hazard, but it can irritate the respiratory tract. By creating a smoky plume behind the vehicle, soot impairs visibility on the roads. The greatest harm to soot lies in the adsorption of benz-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. Diesel fuels contain significantly more sulfur than other fuels used in transport.
Domestic oil fields (especially in the eastern regions) are characterized by a high percentage of sulfur and sulfur compounds. Therefore, the diesel fuel obtained from it is outdated technologies differs in a heavier fractional composition and, at the same time, is less purified from sulfur and paraffin compounds. According to European standards, introduced 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 reason for 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, and eyes of a person, can lead to disruption of carbohydrate and protein metabolism and inhibition of oxidative processes, at high concentrations (over 0.01%) - to poisoning of the body. Sulfurous anhydride has a detrimental effect on the flora.
Eighth group. Components of this group - lead and its compounds - are found in exhaust gases carburetor cars only when using leaded gasoline containing an additive that increases octane number... It determines the engine's ability to operate without detonation. The higher the octane number, the more resistant the gasoline is against detonation. Detonation combustion of the working mixture proceeds at supersonic speed, which is 100 times faster than normal. Engine operation with knocking is dangerous because the engine overheats, its power decreases, and its service life is sharply reduced. An increase in 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, scavenger - ethyl bromide (BgC 2 H 5) and α-monochloronaphthalene (C 10 H 7 Cl), filler - B-70 gasoline, antioxidant - paraoxidiphenylamine and dye. When leaded gasoline is burned, the scavenger helps to remove lead and its oxides from the combustion chamber, converting them into a vapor state. They, together with the exhaust gases, are discharged into the surrounding area and settle near roads.
In roadside areas, approximately 50% of particulate lead emissions are immediately distributed to the adjacent surface. The rest is in the air for several hours in the form of aerosols, and then also settles on the ground near roads. The accumulation of lead in the roadside contaminates ecosystems and makes nearby soils unsuitable for agricultural use.
The addition of P-9 additive to gasoline makes it highly toxic. Various brands gasoline have different percentage of additives. To distinguish between brands of leaded gasoline, they are dyed by adding multi-colored dyes to the additive. Unleaded gasoline is supplied unpainted (Table 9).
In the developed countries of the world, the use of leaded gasoline is limited or has already been completely phased out. It is still widely used in Russia. However, the task is to abandon its use. Large industrial centers and resort areas are switching to the use of unleaded gasoline.
A negative impact on ecosystems is exerted not only by the considered components of engine exhaust gases, separated into eight groups, but also by hydrocarbon fuels, oils and lubricants themselves. Possessing a great capacity for evaporation, especially when the temperature rises, vapors of fuels and oils spread in the air and negatively affect living organisms.
Accidental spills and intentional spills of used oil directly onto the ground or into water bodies occur at places where vehicles are refueled with fuel and oil. Vegetation does not grow at the site of the oil spot for a long time. Oil products that enter water bodies have a detrimental effect on their flora and fauna.
Study of environmental pollution in the village of Toisi by exhaust gases on the Yalchiki - Batyrevo highway. The research work was carried out by A. Rubtsova and V. Russova, grade 10, 2007.
Introduction
There can be no healthy society or socially active citizens without a healthy environment. Unfortunately, at present in Russia, the ecological situation is characterized by the progressive degradation of the natural environment, and the deterioration of the nation's health indicate that the country is not provided with environmental Safety, which is part (along with state, military, personal) national security.
The ecological situation in Russia, as well as throughout the world, is turning from unfavorable to crisis. The ecological crisis situation is aggravated by the fact that the country is going through a change of social and economic relations. Russia inherited a heavy legacy: until the 1990s. the anthropogenic impact on the environment in the USSR increased continuously due to the development of ever more extensive new territories, the growth in the consumption of natural resources for industrial and agricultural production, and an increase in the flow of pollutants.
Relevance of the selected topic.
Our territory of the village of Toisi is exposed to pollution by combustion products from exhaust gases, as well as rubber and asbestos dust. Air pollution affects the health of adults and children. Every year in our school the number of children with chronic respiratory diseases is growing, and immunity is decreasing.
In the dustiness of the air, the main role is played by vehicles. Rubber and asbestos dust is a great danger to human health. Rubber dust is a product of wear car tires... Asbestos dust is a result of wear of friction linings, discs, clutch brake pads... Asbestos is poorly excreted from the body, therefore the process of its effect on internal organs, lungs, mucous membranes is very long, it can reach 10-15 years, and has not yet been fully studied.
The content of the work addresses the following issues:
1. Relevance of the problem under consideration.
2. Impact of exhaust gases on human health.
3. The impact of the growth of the automotive industry on air composition.
4. Exhaust gases are the cause of the appearance of carcinogenic substances in the air.
6. Ways to reduce emissions and exhaust toxicity.
Purpose: study of the problem of air pollution by exhaust gases
Object of study : the process of air pollution by exhaust gases in the village of Toisi per day
Subject of study: the main road Yalchiki - Batyrevo, passing through the village of Toisi with a length of 1 km.
Research hypothesis: air pollution negatively affects human health
Research objectives:
1) To study the question of the ecological situation in Toishi.
2) Find out the impact of exhaust gases on human health.
3) Analyze the impact of the growth of the automotive industry on the composition
air.
4) Justify the reason for the appearance of carcinogenic substances in the air.
5) Study the chemical composition of automobile exhaust gases.
6) Identify ways to reduce emissions and toxicity of exhaust gases.
7) Give examples of typical cases of exhaust gas poisoning in confined spaces.
8) On the basis of the studied issues, draw a conclusion about the negative impact of exhaust gases on human health.
Road transport is one of the main environmental pollutants.
A car would be much more environmentally friendly if its engine converts hydrocarbon fuel exclusively into carbon dioxide and water vapor. But ... The combustion temperature of the fuel is either too high or very low, which leads to incomplete combustion. In addition, one should not forget about the quality of the fuel itself and the impurities contained in it. All this, as you know, leads to the appearance of toxic substances: carbon monoxide, nitrogen and sulfur oxides, unburned hydrocarbons and other gases, as well as particulate matter of soot and lead compounds.
Impact of exhaust gases on human health.
The increase in the incineration of petroleum products is the cause of air pollution. This has become especially noticeable with the development of road transport. Gasoline used to drive internal combustion engines does not disappear anywhere. Giving up the energy of chemical bonds contained in it, it decomposes into simpler substances - carbon oxides, soot, hydrocarbons, etc. The largest amount of air pollutants is emitted with the exhaust gases of cars. Analysis of the exhaust gases of internal combustion engines showed that they contain about two hundred different substances, most of which are toxic. The main components of the exhaust gases are shown in Table 1.
The table shows that the amount of emissions significantly depends on the design of the engine, while diesel engines environmentally more acceptable. However, the quantitative and qualitative composition of exhaust gases depends no less on technical condition, conditions and operating mode of the engine. The concentration of harmful substances in vehicle emissions increases especially sharply when idling.
Carburetor engines emit significantly more unburned hydrocarbons and incomplete oxidation products (aldehydes, carbon monoxide). After passing 15 thousand km, each car emits into the atmosphere more than 3 tons of carbon dioxide, 93 kg of hydrocarbons, 0.5 tons of carbon monoxide, about 30 kg of nitrogen oxides.
In itself, the release of toxic substances into the environment with exhaust gases is highly undesirable, since they pose a real danger to human health. So, carbon monoxide inactivates hemoglobin, causing oxygen deficiency of tissues, causing disorder of the nervous and cardiovascular systems, and also contributes to the development of atherosclerosis. Nitrogen oxides sharply irritate the lungs and respiratory tract, contributing to the onset of inflammatory processes in them. Under the influence of nitrogen oxides, methemoglobin is formed, blood pressure decreases, dizziness, drowsiness, respiratory and circulatory disorders occur.
Traffic fumes
Exhaust gases are the cause of the formation of carcinogenic substances in the air.
Chemical composition of automobile exhaust gases.
The greatest danger is nitrogen oxides, about 10 times more dangerous than carbon monoxide, proportion of toxicity aldehydes relatively small and amounts to 4-5% of the total toxicity of exhaust gases. The toxicity of various hydrocarbons is very different, however, especially that unsaturated hydrocarbons in the presence of nitrogen dioxide are photochemically oxidized to form poisonous oxygen-containing compounds - components smog.
Polycyclic aromatic hydrocarbons found in gases are strong carcinogens. Among them, the most studied benzpyrene, in addition to it, the derivatives anthracene:
· 1,2-benzanthracene
· 1,2,6,7-dibenzanthracene
· 5,10-dimethyl-1,2-benzanthracene
In addition, when using sulphurous gasolines, sulfur oxides can enter the exhaust gases, when using leaded gasolines - lead (Tetraethyl lead ), bromine, chlorine, their connections. It is believed that aerosols of lead halide compounds can undergo catalytic and photochemical transformations, participating in the formation smog.
Research
"Characteristics of the motor transport".
I decided to study the share of environmental pollution from cars passing through our village. The village of Toisi is located in the Batyrevsky district of the Chuvash Republic. Another district is located near our district - Yalchiki. And our village is located just between the villages of Yalchiki and Batyrevo.
It was this fall. One fine day, my friend and I decided to take a walk around the village. We walked for a long time and it was getting boring, but suddenly one wonderful thought came to my mind: to calculate how many cars pass through our village in 1 hour, per day, per week, per year. I expressed my idea to her, she supported me. But cars not only pass, they leave behind harmful and poisonous substances contained in the exhaust gases. How do they affect our health and the environment? We didn't think for a long time. We went to Irina Vitalievna, a biology and chemistry teacher, and told her about our thoughts. She praised us for our quick wit and invited us to write us a research paper on this topic. Vera and I immediately agreed and set to work.
First, we calculated how many cars drove through our village in the morning. On September 6 from 7:00 to 8:00 we counted 48 passenger cars, 12 minibuses (gazelles and UAZs), 10 trucks and 10 tractors. I wonder how many kilograms of exhaust gases enter the atmosphere in the morning? And for the whole day? And in a day? And in a week? And in a year?
It is known that one car during a day can emit up to 1 kg of exhaust gases, which include about 0.03 kg of carbon monoxide, 0.006 kg of nitrogen oxide. Suppose cars are moving at 60 km / h. The length of our village is 1 km. Then they pass our village in 1 minute.
According to my calculations, in the morning, cars emit ~ 0.0549 kg of exhaust gases into our village.
They counted in the afternoon, September 12 from 12:00 to 13:00. Then in 1 hour 32 cars, 12 minibuses (gazelles and UAZs), 8 trucks and 3 tractors passed by. During this period of time, ~ 0.0389144 kg of exhaust gases enter the atmosphere in the village of Toisi.
On September 25, we counted the number of cars passing through our village in the evening. In the evening from 17:00 to 18:00 50 cars, 10 minibuses, 10 tractors drive through our village. Received~ 0.0520kg exhaust.
According to my calculations, a huge amount of exhaust gases also enter our village at night. We counted October 6 in the interval from 23:00 to 24:00. Then 60 cars were passing through our village. This means that at night the exhaust gases enter our village no less than during the day - ~ 0.0416 kg.
Average for 4 hours
|
Cars time |
trucks |
cars |
minibuses |
tractors |
total |
|
12-13 |
|||||
|
17-18 |
|||||
|
23-24 |
Based on all these data, which we calculated, we can calculate the average number of vehicles passing through our village. The average number of vehicles per day is 1656 units, and per week - 11592 units, and per month - 51,336 units, and per year - 616,032 units! This means that ~ 1.15 kg of exhaust gases enter the atmosphere in our village per day, which includes ~ 0.0345 kg of carbon monoxide and ~ 0.0069 kg of nitrogen oxide! And for a year ~ 427.8 kg of exhaust gases, where ~ 12.834 kg is carbon monoxide and ~ 0.0025698 kg is nitrogen oxide!
|
Cars time |
trucks |
cars |
minibuses |
tractors |
total |
|
|
Average for 4 hours |
||||||
|
Average per day |
1140 |
2346 |
||||
|
Average week |
7980 |
1680 |
16422 |
|||
|
Average monthly |
4278 |
35340 |
7440 |
4278 |
72726 |
|
|
Average per year |
50370 |
416100 |
87600 |
50370 |
856290 |
|
In my opinion, this is a huge number for our small village. The environment and the air are polluted. The air isone of the most important elements of the environment. The air environment is essential for human breathing. The human body constantly needs air. This is due to the physiological significance of respiration. When inhaling, air enters the external respiratory organs, which contains the oxygen necessary for the body. A person breathes the air of the room, workplace and air basin settlement, Where does he live. The dispersion of industrial and automotive emissions into the air changes the chemical composition of the atmosphere. Harmful substances are often or constantly found in the air of cities. As waste accumulates in the environment, first the disappearance of species sensitive to pollutants occurs, then, as the resistant species grow, the structure of the ecosystem changes, one ecosystem is replaced by another, or the territory is desertified. The accumulation of wastes in the environment that are toxic to human health causes depression of the health of first individuals with poor health, then the health of a larger and larger part of the population. This is a harsh environmental warning about how fragile defense system of the human body. Thus,human impact on nature in the industrial erahas indeed become a factor surpassing all naturalforces that have ever influenced the development of life, relativescycles undermines the existence of not only differentbiological species, but also himself.
Indeed, we rarely think about the fact that we practically breathe "exhaust gases". After all, when a person is healthy, he feels good, walks, drives a car. ... He probably thinks that when he walks, he breathes fresh and clean air. ... And when a person drives a car, he does not think that he is polluting the environment. environment and air, and then he himself inhales. Yes, I understand that nowadays you cannot do without cars. In order for cars to emit less harmful substances into the environment, it is necessary to install other engines on them, which would not emit as much exhaust gas as the engines of modern cars.
How many villages and villages like ours, but what are the villages and villages, how many districts and cities that, in addition to cars, are also polluted by factories, factories, industrial enterprises, etc. If only in our village ~ 1.15 kg of exhaust gas enters the atmosphere per day, then in Batyrevsky district there are 48 villages and villages, which means that approximately 55.5 kg of exhaust gas enter the atmosphere! And this is just a day! And for a year - ~ 20257.5 kg of exhaust gas! This is a huge amount! This is not only harmful to the environment and the air, but primarily to our health!
We also calculated how much dust settles per day in our village when passing vehicles.
In a day, 1,200 passenger cars, 240 minibuses (gazelles and UAZs), 14 trucks pass through our village. On 1 km of the road, an average of 0.2 grams of dust settles on one car. Multiply by the number of vehicles passed - 290.8 grams. per day, 103.5 kg per year.
|
Components |
Note |
||
|
Carburetor |
Diesel |
||
|
N 2 O 2 H 2 O (Vapors) CO 2 H 2 CO NO x C n H m Aldehydes Soot Benzapiren |
74-77 0,3 – 8 3,0 – 5,5 5,0 – 12,0 0 – 5,0 0,5 – 12,0 Up to 0.8 0,2 – 3,0 Up to 0.2 mg / l 0- 0.004 g / m 3 10 - 20 μg / m 3 |
76- 78 2 – 18 0,5 – 4,0 1,0 – 10,0 0,01 – 0,50 0,0002 – 0,5 0,009 – 0,5 0.001-0.09 mg / l 0.01 - 1.1 g / m 3 Up to 10 μg / m 3 |
Non-toxic Toxic |
Conclusion.
And in conclusion, I want to say that when creating this project, it took me a lot of time to conduct research, find additional information... This information is not unimportant for me.
Everyone should think about the serious consequences of an atmosphere saturated with harmful chemicals. The life given to us once by nature should not be disturbed by artificial factors that negatively affect human health.
Think about it!
References:
1) "Avanta +" Moscow 2002
2) Alikberova L.Yu. Chemistry book for home reading. - 2nd ed. - M .:
3) Chemistry, 1995.
4) V. Volodin “Man. Encyclopedia for Children "
5) N.L. Glinka "General chemistry"
Have you ever wondered how much one car absorbs oxygen and emits carbon dioxide CO2 per year?
How many trees does it take to convert this amount of CO2 back into oxygen? Let's count as "math" interest ...
What do we know about carbon dioxide CO2?
Plants release oxygen and absorb carbon dioxide.
People and animals breathe oxygen, and exhale carbon dioxide. This maintains a constant amount of oxygen and carbon dioxide in the air.
However, it is a mistake to say that animals only emit carbon dioxide, while plants only absorb it. Plants absorb carbon dioxide in the process photosynthesis, and without lighting, they also highlight it.
The air always contains a small amount of carbon dioxide, about 1 liter in 2560 liters of air. Those. the concentration of carbon dioxide in the Earth's atmosphere averages 0.038%.
When the concentration of CO2 in the air is more than 1%, inhalation of it causes symptoms that indicate poisoning of the body - "Hypercapnia": headache, nausea, frequent shallow breathing, increased sweating and even loss of consciousness.
As you can see in the diagram above, the concentration of carbon dioxide on Earth is growing (I draw your attention that these are measurements not in the city, but on the Mauna Loa Mountain in Hawaii) - the share of carbon dioxide in the atmosphere from 1960 to 2010 increased from 0.0315% to 0 , 0385%. Those. growing steadily + 0.007% over 50 years. In the city, the concentration of carbon dioxide is even higher.
Carbon dioxide concentration in the atmosphere:
- in the pre-industrial era - 1750:
280 ppm (parts per million) total weight - 2200 trillion kg - currently - 2008:
385 ppm, 3,000 trillion kg total
Activities with CO2 emissions(some everyday examples) :
- Driving (20 km) - 5 kg CO2
- Watching TV for an hour - 0.1 kg CO2
- Microwave cooking (5 min) - 0.043 kg CO2
Photosynthesis is the only source of atmospheric oxygen.
In general, the chemical balance of photosynthesis can be represented as a simple equation:
6CO 2 + 6H 2 O \u003d C 6 H 12 O 6 + 6O 2
The first to discover that plants emit oxygen was the English chemist and philosopher Joseph Priestley around 1770. It was soon established that this requires light and that oxygen is emitted only by green parts of plants. The researchers then found that plant nutrition requires carbon dioxide (carbon dioxide, CO2) and water, from which most of the plant mass is made. In 1817, French chemists Pierre Joseph Pelatier (1788–1842) and Joseph Bienneme Cavant (1795–1877) isolated the green pigment chlorophyll.
By the middle of the 19th century. it was found that photosynthesis is a process, as it were, the reverse of respiratory. Photosynthesis is based on the conversion of electromagnetic energy of light into chemical energy.
Photosynthesis, which is one of the most common processes on Earth, determines the natural cycles of carbon, oxygen and other elements and provides the material and energy basis for life on our planet.
Environmental arithmetic
Within one year, a typical tree gives off the amount of oxygen needed for a family of 3. And the car absorbs the same amount of oxygen when burning 1 tank of gasoline 50 liters.
- 1 tree absorbs on average within 1 year 120 kg CO2, and gives off about the same amount of oxygen
- 1 car absorbs the same volume of oxygen (120 kg) when burning about 50 liters of gasoline,and generates various exhaust gases (their composition is indicated in the table)
|
Exhaust gas composition: |
Petrol engines | Diesel | Euro 3 | Euro 4 |
| N 2, vol.% | 74-77 | 76-78 | ||
| O 2, vol.% | 0,3-8,0 | 2,0-18,0 | ||
| H 2 O (vapor), vol.% | 3,0-5,5 | 0,5-4,0 | ||
| CO 2, vol.% | 0,0-16,0 | 1,0-10,0 | ||
| CO * (carbon monoxide), vol.% | 0,1-5,0 | 0,01-0,5 | up to 2.3 | up to 1.0 |
| NOx, Nitrogen oxides *, vol.% | 0,0-0,8 | 0,0002-0,5 | up to 0.15 | up to 0.08 |
| CH, Hydrocarbons *, vol.% | 0,2-3,0 | 0,09-0,5 | up to 0.2 | up to 0.1 |
| Aldehydes *, vol.% | 0,0-0,2 | 0,001-0,009 | ||
| Soot **, g / m3 | 0,0-0,04 | 0,01-1,10 | ||
| Benzpyren-3.4 **, g / m3 | 10-20 × 10 −6 | 10 × 10 −6 |
* Toxic components ** Carcinogens
- 1 car is refueled per year 1500 liters of gasoline (with a mileage of 15,000 km and a flow rate of 10l / 100km). This means that it is necessary 1500 l / 50 l in tank \u003d 30 treeswhich will develop the absorbed volume of oxygen.
- 1 auto center in Moscow sells about 2000 cars per year (size of one parking lot). Those. 30 trees multiplied by 2000 cars per year \u003d 60,000 trees for 1 auto center.
- Let's start small: 2000 trees (1 tree for 1 car) - is that a lot or a little? No more than 400 trees can be planted on one football field (20 x 20 after 5 meters is the recommended distance). It turns out that 2000 trees will occupy the territory - 5 football fields!
- How much does it cost to plant 1 tree? - you can unsubscribe in the comments.
Poplars are the most active oxygen suppliers. 1 hectare of such trees releases 40 times more oxygen into the atmosphere than 1 hectare of spruce stands.
Ways to reduce emissions and toxicity
- A huge impact on the amount of emissions (not counting fuel combustion and time) plays traffic organization cars in the city (a significant part of emissions occurs in traffic jams and at traffic lights). With a successful organization, it is possible to use less powerful engines, at low (economical) intermediate speeds.
- Significantly reduce the content of hydrocarbons in waste gases, more than 2 times, possibly by using as fuel associated petroleum (propane, butane), or natural gas basics, despite the fact that main drawback natural gas - low power reserve, not so important for the city.
- In addition to the fuel composition, toxicity is affected by engine condition and tuning (especially diesel - soot emissions can increase up to 20 times and carburetor - nitrogen oxide emissions change up to 1.5-2 times).
- Significantly reduced emissions (reduced fuel consumption) in modern structures engines with injection power supply with a stable stoichiometric mixture of unleaded gasoline with the installation of a catalyst, gas engines, units with air superchargers and coolers, using a hybrid drive. However, such designs greatly increase the cost of cars.
- SAE tests have shown that effective method reduction of nitrogen oxide emissions (up to 90%) and toxic gases in general - water injection into the combustion chamber.
- There are standards for the cars produced. In Russia and European countries, EURO standards have been adopted, setting both toxicity and quantitative indicators (see the table above)
- In some regions, traffic restrictions heavy vehicles (for example, in Moscow).
- The signing of the Kyoto Protocol
- Various ecological actions, for example: Plant a tree - give the Earth oxygen!
What you need to know about the Kyoto Protocol?
Kyoto Protocol - an international document adopted in Kyoto (Japan) in December 1997 in addition to the United Nations Framework Convention on Climate Change (FCCC). It obliges developed countries and countries with economies in transition to reduce or stabilize greenhouse gas emissions in 2008-2012 compared to 1990.
As of March 26, 2009 the Protocol was ratified by 181 countries of the world (these countries together account for more than 61% of global emissions). The notable exception to this list is the United States. The first implementation period of the protocol began on 1 January 2008 and will last for five years until December 31, 2012after which a new agreement is expected to replace it.
The Kyoto Protocol was the first global agreement on environmental protection based on a market-based regulatory mechanism - the mechanism of international trading in greenhouse gas emissions.
Artificial trees, real oxygen
Scientists at Columbia University in New York have partnered with French design studio Influx Studio to develop artificial trees. By and large, this is a car styled like a dracaena, with wide branches and an umbrella-shaped crown. Branches are used to support solar panels that power the trees.
Artificial trees will look like huge lanterns that shimmer in the dark. different colors... Mechanical dracaena will not only bring practical benefits, but also become an adornment of the modern metropolis.
In addition to converting carbon dioxide into oxygen, artificial trees can serve as an additional source of energy. In addition to solar panels, it will be generated by converting mechanical energy from a swing set at the base.
Outwardly, such artificial trees resemble dracaena, and they consist of recycled wood and plastic. The bark of such a "tree" contains solar panels and filters to absorb carbon dioxide. In the "trunks" of artificial trees there is water and tree resin - with their participation the process of photosynthesis will take place. To support the operability of such trees, a special swing will be used: the merry townspeople will become electricity generators.
Bought a car - plant 12 hectares of forest
In everyday life, we often encounter problems of lack of water or food. They cause us some inconvenience. There are, however, things, the deficit of which is accumulating imperceptibly, but in the near future risks becoming a serious problem for ensuring the life of mankind.
According to research by environmentalists, in large cities, almost 90% of air pollution is accounted for by vehicle exhaust. Diesel vehicles are the worst pollutants. The type of gasoline burned also plays an important role. For example, sulphurous gasoline releases sulfur oxides into the atmosphere, while chlorine, bromine and lead. But the most common composition of exhaust gases 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 hemoglobin and causes tissues and organs in the body. This leads to headaches, dizziness, loss of consciousness and even death.
It is not uncommon for a car to warm up in a closed or even open garage and lead to the death of the car owner. Odorless and colorless, carbon monoxide leads to unconsciousness and death.
Nitrogen dioxide
Yellowish brown gas with a pungent odor. Reduces visibility, gives the air a brownish tint. It is 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 ultraviolet radiation from the sun, hydrocarbons are oxidized, after which they form oxygen-containing poisonous substances with a pungent odor, the so-called photochemical smog. Cyclic aromatic hydrocarbons are also found in resins and soot, they are the strongest carcinogens. Some of them are capable of causing mutations.
Formaldehyde
A colorless gas with an unpleasant and pungent odor. In large quantities, irritating to the respiratory tract and eyes. It is toxic, causes damage to the nervous system, has a mutagenic, allergenic and carcinogenic effect.
Dust and soot
Suspended particles, no more than 10 microns in size. May 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.
