Protecting the atmosphere from pollution. II. Protection of atmospheric air from pollution. Major air pollutants

Goals:

generalize knowledge about the sources of air pollution, the consequences they lead to and air protection rules;
formulate rules for personal environmental safety;
develop memory, logical thinking, vocabulary;
foster respect for the environment.

DURING THE CLASSES

1. ORGANIZATIONAL POINT (1 min)

2. Introduction to the topic of the LESSON (2 min)

Red Crow:

Not enough fresh air! I can not breathe! I even changed the color. I'm suffocating! Help!

I propose to help CROW. Based on her request, how to formulate the topic of the lesson? (How to protect yourself from air pollution). "Appendix 1=slide 1."

What questions should we answer for her? / What causes air pollution and what does it lead to? What needs to be done to protect air from pollution? How to protect yourself from air pollution? /"Appendix 1=slide 2".

I propose to conduct the lesson in the form of a conference at which you will be environmental scientists. Before our environmental conference begins, I would like to remind you of the following information:

"Appendix 1=slide 3" The atmosphere is the layer of air surrounding the Earth. Its thickness reaches 1000 kilometers. Air does not fly away from the Earth, since it attracts it to itself, like any body. The atmosphere is of great importance for life on Earth: it protects the Earth from meteorites, scatters the sun's rays, which would otherwise burn the Earth and everything on it.

3. Test of knowledge on homework (12 min).

Atmospheric air becomes heavily polluted as a result of an increase in impurities in the air, such as carbon dioxide. There is more and more of it in the air. The expression “I can’t breathe” is increasingly found in the conversations of most citizens.

As the environmental conference progresses, you will fill out an ecologist sheet "Appendix 2", in which you will record all the stages of work on this topic.

Name the sources of air pollution; to do this, build chains of harmful substances entering the body. We covered this material in the previous lesson.

1. The car has become the worst enemy of nature and man. It ranks first in terms of emissions of harmful substances into the environment. Please note: 1 car per year emits a little more than a ton of exhaust gases, which contain 200 types of harmful substances. The same car produces 10 kg of rubber dust. In addition, it raises whole clouds of dust; plants along the roads are contaminated with hard metals. Thus, the car is one of the main sources of pollution.

/ option:

car - exhaust gases - org. breathing
car - dust - soil or plants - org. digestion/

2. There is almost no vegetation around factories; grass and shrubs have died, and there are frail trees. The reason is that the plant emits huge amounts of pollutants when burning fuel. When 10 tons of coal are burned, 1 ton of sulfur dioxide is released, while 1 ton of dust falls per 1 km per day. Millions of tons of ash are transported to dumps.

/ dumps - smog - org. breathing/

3. The smell of freshness after a thunderstorm is the smell of ozone. Oxygen is converted into it during a lightning discharge. By the way, there is a smell of the same ozone near a working copier: in the machine, under the influence of ultraviolet radiation, oxygen also turns into ozone.

This gas blanket covers the Earth at an altitude of 18-25 meters. It is what blocks the sun's rays, which are destructive to all living things.

The reason for its destruction is gases containing chlorine in their molecule. Freon is also dangerous for ozone. This is a volatile substance that is pumped into aerosol cans to create the necessary pressure. More than 20 years ago, scientists discovered the first ozone hole over Antarctica. Here the ozone layer has almost disappeared.

4. Smoke is very small solid particles that appear in the air when wood, coal, or fuel burn. Smoke particles are so light that they float in the atmosphere for years.

Smoke is harmful. It irritates the respiratory system and corrodes the eyes. Heavy metals (lead, mercury) cause changes in the blood.

cigarette smoke - org. breathing
smoke from combustion - fog or smog - plants - org.digestion and org. breathing/

5. Accidents. This happened on April 26, 1986 at a nuclear power plant in the city of Pripyat, which is located near Chernobyl. One day there was an explosion and the block caught fire. At the same time, such a quantity of radioactive substances was released into the air that people who were nearby, and especially firefighters, received a lethal dose of radiation.

Fortunately, such accidents are rare, but millions of minor accidents occur every year.

/ accident - release - acid rain - plants or soil - org. digestion/

/ as student responses are received, entries appear:

1. Exhaust gases

2. Factory emissions

3. Dumps.

5. Volatile substances.

CONCLUSION: So what sources of air pollution have we named?/ "Appendix 1=slide 4"

REFLECTION:

3. PREPARATION FOR ACTIVE MENTAL ACTIVITY (3 min).

"Appendix 1 = Slide 5"

What effect does air pollution have on plants and animals?

6. SMOG comes from combinations of 2 English words - smoke and fog. This is a harmful fog that forms in cities. In 1959, heavy smog in London, consisting of soot particles, sulfur dioxide and fog droplets, killed 4 thousand people.

7. I have the following data. In Holland, 1/3 of the trees were affected by acid rain. At the height of summer, the leaves suddenly fell, the roots died, the trees turned yellow and withered, and the fish disappeared from the lakes. In southern Norway, fishermen could not catch fish in half the lakes. Due to acid rain, architectural monuments are destroyed. But most importantly, human health suffers.

How is acid rain formed?

Tall factory chimneys emit sulfur dioxide into the air, it combines with atmospheric moisture, and droplets of sulfuric acid solution are formed. These toxic substances permeate the clouds, which the wind carries for thousands of kilometers. This is how acid rain falls.

(Draw on the extension board)

DYNAMIC PAUSE (3 min)

4. Learning new material (12 min)

What air protection measures should be taken?

There are a lot of ways. Let's find out the main ways.

Differentiated work:

Strong students solve the problem situation “Where to build a factory,” as a result of which a diagram appears in a notebook. (Discussion of the correct option)

Solve the problem and highlight the way to protect the air. Secondary students solve environmental problems:

1.Trees help clear the air of dust and other pollutants. A deciduous forest, the area of which is equal to the area of a square with a side of 100 m, can retain 68 tons of dust during the year. But a spruce forest of the same area is capable of “swallowing” 32 tons of dust in the same time. How many tons of dust does a deciduous forest retain more than a spruce forest?

2. In the house where Lena lives, waste metal, paper, plastic, glass, as well as food waste are thrown into different containers. Thereby most waste, thrown away by the residents of this house, can be recycled and reused. A container intended for metal contains 12 kg of waste, for glass - 6 kg, for paper - 7 kg, but a container for plastic contains 3 kg of waste less than a container for paper. The food waste container contains 9 kg more waste than the plastic container. How many kilograms of garbage are in each container?

3. In the city where Valya and Tanya live, there are no cleaning filters or dust catchers on the factory pipes, so both girls are collecting signatures on a letter to the authorities with a request build cleaning filters and install dust catchers. Valyusha collected 7 signatures, and Tanyusha - 4 times more. How many signatures did the girls collect?

4. You can't light a fire in the forest. Vasya and Kolya forgot about it. The fire they lit set the forest on fire. 96 trees burned. The boys were very ashamed, and they decided that they would correct the evil they had caused by planting 4 young trees to replace each one that burned down due to their fault. How many trees were the boys going to plant?

Examination. "Appendix 1=slide 6"

Formulate rules for personal environmental safety.

(Students who have learning difficulties read page 31 of the textbook and answer the question: “How to protect yourself from polluted air?”)

If you are walking along the road and the air is polluted, go to the next street.

Don't stop on the street near a car with the engine running.

Don't linger in places where it's smoky. Cigarette smoke is a dangerous air pollutant.

PRIMARY CHECKING OF NEW MATERIAL

Add your own rules. (Collective compilation of a memo for air purification)

1.As you answer, the following slides appear on the board:

Installation of cleaning filters on factory pipes

Forest plantations

Smoke eliminator devices

Banning fires in forest parks

Recycling

Summarizing.

"Appendix 1=slide 7"

REFLECTION:

Use a traffic light to indicate the correct answer.

5. Fixing the material (up to 4 minutes)

Take the test and find out what every living thing on the planet needs

/test/ (self-assessment)

1. What substances make up air?

A) hydrogen, copper, zinc

B) oxygen, nitrogen, carbon dioxide

D) chlorine, fluorine, iodine

2. What air gas is needed for breathing?

O) oxygen

U) carbon dioxide

3. What gas do plants absorb when breathing?

C) oxygen

H) carbon dioxide

4. Do humans and other living beings need clean air to breathe?

T) No, not needed.

D) Yes, it is necessary.

5. How should we protect air from pollution?

S) stop all factories and factories, stop logging. Prohibit the use of vehicles that emit harmful substances into the environment. Turn the Earth into one huge reserve.

U) Factories and factories must have dust and harmful substance traps. Transport must be made environmentally friendly. Create belts of gardens, parks and forests in and around cities. Plant young trees in place of felled trees

6.Which representatives of wildlife can influence the cleanliness of the air?

L) animals

X) plants

H) mushrooms and microbes

REFLECTION:

Use a traffic light to indicate the correct answer.

6. Generalization and systematization (2 min)

Let's remember what our environmental conference was dedicated to.

"Appendix1=slide 8"

7. RESULT OF THE LESSON (2 min)

Guys, who will explain to the crow the causes of air pollution and tell him what he needs to do in order not to breathe polluted air? How can we help the residents of our city in the fight for clean air, and what rules must they follow?

8. D/Z (2 min)

Draw environmental signs to protect air from pollution.

Come up with symbols for the rules of personal environmental safety.

We have completed the conference program. What new rules will you follow to keep the air clean (Assessment)

Reflection(red and green traffic lights) (1 min)

Determine the degree of significance of this topic for a person.
Indicate your attitude to this problem.
Determine the extent to which you have studied this topic in class.

Air is a natural mixture of gases, mainly nitrogen and oxygen, that forms the earth's atmosphere. Air is necessary for the normal existence of the vast majority of terrestrial living organisms: the oxygen contained in the air enters the body's cells during respiration and is used in the oxidation process, which results in the release of energy necessary for life (metabolism, aerobes). In industry and in everyday life, atmospheric oxygen is used to burn fuel to produce heat and mechanical energy in internal combustion engines. Inert gases are obtained from air by liquefaction. In accordance with the Federal Law “On the Protection of Atmospheric Air,” atmospheric air is understood as “a vital component of the environment, which is a natural mixture of atmospheric gases located outside residential, industrial and other premises.” Air is a natural mixture of gases, mainly nitrogen and oxygen, that forms the earth's atmosphere. Air is necessary for the normal existence of the vast majority of terrestrial living organisms: the oxygen contained in the air enters the body's cells during respiration and is used in the oxidation process, which results in the release of energy necessary for life (metabolism, aerobes). In industry and in everyday life, atmospheric oxygen is used to burn fuel to produce heat and mechanical energy in internal combustion engines. Inert gases are obtained from air by liquefaction. In accordance with the Federal Law “On the Protection of Atmospheric Air”, atmospheric air is understood as “a vital component of the environment, which is a natural mixture of atmospheric gases located outside residential, industrial and other premises”. inert gases

Chemical composition In 1754, Joseph Black experimentally proved that air is a mixture of gases, and not a homogeneous substance. 9341.292 Carbon dioxideCO 2 0.03140.046 NeonNe0.0014 MethaneCH 4 0.00020, HeliumHe0, KryptonKr0.003 HydrogenH2H2 0.000050.00008 XenonXe0.00004

The main sources of air pollution are emissions from industrial enterprises, as well as the processes of evaporation and combustion of fuel (thermal power plants, internal combustion engines, etc.), forest fires. Air pollutants as a result of meteorological processes spread in the atmosphere over significant distances, which leads to global air pollution on our planet. Now there is no longer a fundamental difference in the composition of atmospheric air in rural and industrial regions (the difference is only in the quantitative content of pollutants). The main sources of air pollution are emissions from industrial enterprises, as well as the processes of evaporation and combustion of fuel (thermal power plants, internal combustion engines, etc.), forest fires. Air pollutants as a result of meteorological processes spread in the atmosphere over significant distances, which leads to global air pollution on our planet. Nowadays there is no longer a fundamental difference in the composition of the atmospheric air of rural and industrial regions (the difference is only in the quantitative content of pollutants). sources of air pollution forest fires sources of air pollution forest fires In these conditions, the problem of combating air pollution, which is especially acute in industrialized countries, becomes of paramount importance. Reasonable use of natural resources and nature conservation, creation of state reserves and national parks, increasing the number of green spaces, reducing industrial emissions of harmful chemicals into the atmosphere and the development of waste-free chemical technology are the main ways to solve environmental problems, the goal of which is ultimately the benefit of all mankind. However, solving such a set of problems for the protection of atmospheric air and other environmental objects is impossible without creating an effective air quality control system. The need to develop comprehensive methods for the determination of various toxic substances in the atmosphere is widely recognized. Under these conditions, the problem of combating air pollution, which is especially acute in industrialized countries, becomes of paramount importance. Reasonable use of natural resources and nature conservation, creation of state reserves and national parks, increasing the number of green spaces, reducing industrial emissions of harmful chemicals into the atmosphere and the development of waste-free chemical technology are the main ways to solve environmental problems, the goal of which is ultimately the benefit of all mankind. However, solving such a set of problems for the protection of atmospheric air and other environmental objects is impossible without creating an effective air quality control system. The need to develop comprehensive methods for the determination of various toxic substances in the atmosphere is widely recognized. natural resources non-waste environmental problems natural resources non-waste environmental problems

Protecting the environment from pollution is one of the most important problems of our time. Getting into the air, water and soil, toxic chemicals (industrial poisons) create a real threat to the existence of humans, plants and animals on our planet. The development of industry and transport, increasing population density, human penetration into the stratosphere and outer space, intensification of agricultural production (use of pesticides), transportation of petroleum products, burial of hazardous chemicals at the bottom of seas and oceans and ongoing testing of nuclear weapons all contribute to global and ever-increasing pollution. the natural habitat surrounding humans. Protecting the environment from pollution is one of the most important problems of our time. Getting into the air, water and soil, toxic chemicals (industrial poisons) create a real threat to the existence of humans, plants and animals on our planet. The development of industry and transport, increasing population density, human penetration into the stratosphere and outer space, intensification of agricultural production (use of pesticides), transportation of petroleum products, burial of hazardous chemicals at the bottom of seas and oceans and ongoing testing of nuclear weapons all contribute to global and ever-increasing pollution. the natural habitat surrounding humans. Protection of the environment, pollution of the habitat Protection of the environment, pollution of the habitat

It is known that a person can live without food for more than one month, without water - only a few days, but without air - only a couple of minutes. Our body needs it! Therefore, the question of how to protect air from pollution should occupy a high priority among the problems of scientists, politicians, statesmen and officials of all countries. To avoid killing ourselves, humanity must take urgent measures to prevent this pollution. Citizens of any country are also obliged to take care of cleanliness. It just seems that practically nothing depends on us. There is hope that through joint efforts we can all protect the air from pollution, animals from extinction, and forests from deforestation.

Earth's atmosphere

Earth is the only planet known to modern science on which life exists, which was made possible thanks to the atmosphere. It ensures our existence. The atmosphere is, first of all, air, which must be suitable for breathing by people and animals, and not contain harmful impurities and substances. How to protect air from pollution? This is a very important issue that will have to be resolved in the near future.

Human activity

In recent centuries, we have often behaved extremely unreasonably. Mineral resources are wasted in vain. Forests are being cut down. The rivers are drying up. As a result, the natural balance is disrupted and the planet gradually becomes uninhabitable. The same thing happens with air. It is constantly polluted by all sorts of things entering the atmosphere. Chemical compounds contained in aerosols and antifreezes are destroying the Earth, threatening global warming and related disasters. How to protect air from pollution so that life on the planet continues?

The main reasons for the current problem

Gaseous waste from factories and factories, released into the atmosphere in countless quantities. Previously, this happened completely uncontrollably. And on the basis of waste from enterprises that polluted the environment, it was possible to organize entire plants for their processing (as they do now, for example, in Japan).
Cars. Burnt gasoline and diesel fuel form which escape into the atmosphere, seriously polluting it. And if you take into account that in some countries there are two or three cars for every average family, you can imagine the global nature of the problem under consideration.
Combustion of coal and oil in thermal power plants. Electricity, of course, is extremely necessary for human life, but extracting it in this way is real barbarity. When burning fuel, a lot of harmful emissions are generated, which heavily pollute the air. All impurities rise into the air with smoke, are concentrated in clouds, and spill onto the soil in the form of trees, which are intended to purify oxygen, and suffer greatly from this.

How to protect air from pollution?

Measures to prevent the current catastrophic situation have long been developed by scientists. All that remains is to follow the prescribed rules. Humanity has already received serious warnings from nature itself. Especially in recent years, the world around us is literally shouting to people that the consumer attitude towards the planet must be changed, otherwise - the death of all living things. What do we have to do? How to protect the air from pollution (pictures of our amazing nature are presented below)?

According to environmental experts, such measures will contribute to a significant improvement in the current situation.

The materials presented in the article can be used in a lesson on the topic “How to protect air from pollution” (grade 3).

Air protection is one of the most pressing problems of environmental protection. Protecting the atmosphere from pollution from industrial and transport emissions is the most important social task, part of the complex of tasks of the global problem of nature conservation and improving the use of natural resources. Air pollution with harmful substances causes significant material damage to the national economy and leads to an increase in morbidity among the population.

Problems of atmospheric protection constitute a broad area at the intersection of sciences. It includes both general problems of chemical technology, energy, physics and mechanical engineering, as well as issues that are dealt with by doctors, hygienists, etc.

The most effective method of protecting the atmosphere from pollution by harmful substances is the development of new low-waste, resource- and energy-saving technological processes with closed production cycles. However, these issues require large financial costs and the development of new modern technologies and materials. Therefore, without postponing the solution of these issues to the future, at the present stage for most industrial and transport enterprises, cleaning the air emitted into the atmosphere remains the main measure to protect the air basin from pollution.

Of the total mass of air pollutants,

coming from anthropogenic sources, about 90% are various gaseous substances, and 10% are solid and liquid substances.

Suspended substances in the air are called aerosols, which are usually divided into three classes: dust, smoke and mists.

Dusts are polydisperse systems of solid suspended particles ranging in size from 5 to 100 microns.

Fumes are aerosols with particle sizes from 0.1 to 5 microns.

Fogs are liquid aerosols consisting of liquid droplets. They may contain dissolved substances or solid particles. They are formed as a result of condensation of steam or spraying of liquids. The particle size in the first case is close to smoke, and in the second - to dust.

A special place is occupied by soot and ash formed during the combustion of fuel.

Soot is a toxic highly dispersed powder, 95% consisting of carbon particles.

Ash is an unburned fuel residue consisting of mineral impurities.

In dust collection and gas purification technology, the dispersed composition of dust is of decisive importance, since depending on this, the appropriate dust collection equipment is selected.

The most typical gaseous air pollution includes:

sulfur dioxide ( SO 2 ),

carbon monoxide ( CO),

nitrogen oxides and dioxides ( NO, NO 2 ),

hydrocarbons (gasoline vapor, methane, etc.),

compounds of heavy metals (lead, mercury, cadmium, etc.),

carbon dioxide ( CO 2).

Naturally, there may be other harmful gaseous substances in the air due to the presence of a particular production facility nearby. Emissions into the atmosphere are divided into:

1 – steam-gas and aerosol;

2 – technological and ventilation;

3 – organized and unorganized;

4 – heated and cold.

According to the 1st classification, vapor-gas emissions are a mixture of gases that do not contain solid or liquid particles. Aerosol emissions are a mixture of gases carrying solid or liquid particles.

Depending on the harmfulness of the gas components and the aerosol particles they contain, it is necessary to clean either one component of the mixture or the mixture as a whole. In the latter case, either combined cleaning in one apparatus or a combination of sequential arrangement of apparatuses is required.

Technological emissions are formed as a result of technological processes and represent emissions during blowing, emissions from safety valves, from boiler pipes, vehicles, etc. As a rule, they are characterized by a high concentration of pollutants. Ventilation emissions are characterized by large volumes of gas-air mixture, but low concentrations of pollutants. At the same time, due to the large volumes of the gas-air mixture, the gross emissions of pollutants with them can be significant.

Organized emissions include emissions removed by pipes or flues, which makes it quite easy to use gas and dust collection units. Unorganized emissions include emissions from depressurized equipment, emissions from unequipped places for loading or unloading materials, from transport systems, etc.

Hot or cold emissions are distinguished by the temperature difference between the gas and the surrounding environment. With a temperature difference of up to 30°C, emissions can be considered cold.

The operation of any device that removes suspended particles is based on the use of one or more sedimentation mechanisms. The main ones that have the greatest application include: gravitational deposition, deposition under the influence of centrifugal forces, inertial deposition, entanglement (touch effect), diffusion deposition, electrodeposition. Modern methods include thermophoresis and exposure to an electromagnetic field. The influence of a particular mechanism on the deposition of particles is determined by a number of factors, and primarily their size.

Gravity settling occurs as a result of particles settling vertically under the influence of gravity. When falling, a dust particle experiences resistance from the environment, so the speed of falling or settling is determined by the condition of equality of gravity and hydraulic resistance. Therefore, particles of smaller diameter will have a lower settling rate and to clean the air from such particles, a longer residence time of the dust-laden flow in the dust-sedimentation chamber will be required.

Centrifugal dust deposition is observed during the curvilinear movement of a dust-laden flow, when, under the influence of developed centrifugal forces, dust particles are thrown onto the deposition surface. In devices based on the use of centrifugal forces, two fundamental design solutions can be used. In one case, the dust and gas flow rotates in a stationary body of a cylindrical or conical apparatus. And in the second case, the dust and gas flow moves in a rotating rotor. The first solution is carried out in cyclones, and the second - in rotary dust collectors.

Inertial deposition occurs when the mass of a dust particle cannot follow along with the gas along a flow line enveloping a substance that is dense compared to air; due to inertia, when the flow turns, it continues to move in a straight line. In this case, a dust particle collides with an obstacle and settles on it. Inertial settling of dust particles is effective for particles larger than 1 micron.

Diffusive deposition will occur when particles, which are generally small in size, are subject to Brownian motion

molecules. As a result, they have an increased likelihood of contact with the streamlined body. The efficiency of diffusion deposition is inversely proportional to particle size and gas flow velocity.

The deposition of dust particles under the influence of an electric current consists of charging the particles and then separating them from the air under the influence of an electric field. Electrical charging of dust particles can be carried out during the generation of an aerosol, due to the diffusion of free currents and during a short discharge. In the latter case, dust particles are charged with the same sign, which makes it possible to increase the efficiency of their subsequent removal from the air flow.

Thermophoresis is the repulsion of particles by a heated body caused by the movement of air as a result of the occurrence of free convection. During thermophoresis, the concentration of particles in areas of high and low temperatures becomes different, which leads to thermal diffusion of particles towards lower temperatures. In practice, this can be observed in the form of dust deposited on the external walls against central heating appliances.

The deposition of suspended particles upon contact of a gas flow with a liquid can occur on drops, bubbles and on the surface of the liquid.

The capture of suspended particles by droplets is based on kinematic coagulation resulting from the difference in the velocities of particles and droplets.

This may happen:

When the aerosol moves at low speed and the liquid droplets fall under the influence of gravity;

When aerosol and droplets move in the same or opposite directions at different speeds.

When polluted air bubbles move through a layer of liquid (bubbling), a pulsation of gases occurs inside the bubbles. Suspended particles stick to the surface of the water surrounding the gas bubble.

When solid particles are deposited on the surface of a liquid, in the case when a gas flow moves along the liquid surface, the particles are deposited in the water in the volume of a thin film, i.e. surface water pollution occurs.

Gas filtration through porous materials involves passing the aerosol through filter baffles, which allow air to pass through but trap aerosol particles. The filtration process in the most common filters can be conventionally accepted as the process of flow around a cylinder located across the flow. Dust particles are retained on the surface of the fibers by molecular interaction forces. Filtration of a dusty flow through a porous material is much more complicated, since it involves not only the process of adhesion to the material as a result of flow, but also due to collision with fibers or threads. It must be taken into account that there are usually several rows of fibers along the path of the dusty flow, which increases the cleaning efficiency.

When extracting gaseous impurities, absorption, adsorption, catalysis and thermal oxidation methods are used.

Absorption purification is based on the ability of liquids to dissolve gases or chemically interact with them. During absorption, a substance transitions from the gas phase to the liquid phase. The substance in which the absorbed gas components are dissolved is called an absorbent. The remainder of the gas stream that is not absorbed into the liquid is usually called inert gas. During physical absorption, physical dissolution of the absorbed component in the solvent (absorbent) occurs. In this case, no chemical reactions occur. This process occurs when the partial pressure of the absorbed component in the gas is greater than the equilibrium partial pressure above the surface of the solution.

During chemical absorption (chemisorption), the absorbed component enters into a chemical reaction with the absorbent (liquid), forming new chemical compounds in the liquid phase. Chemisorption processes provide more complete extraction of components from gas mixtures. The amount of gases that can be dissolved in a liquid depends on the properties of the gas and liquid, the temperature and the partial pressure of the gas above the liquid.

The absorption process refers to the absorption of a gas component by a solid substance. The phenomenon of adsorption is due to the presence of attractive forces between the molecules of the adsorbent (solid) and the absorbed gas at the interface between the contacting phases. The process of transfer of molecules from gas to the surface layer of the adsorbent occurs if the attractive forces of the adsorbent exceed the attractive forces from the carrier gas. The molecules of the adsorbed substance, moving to the surface of the adsorbent, reduce its energy, resulting in the release of heat.

During physical adsorption, gas molecules do not enter into chemical interaction with adsorbent molecules. With increasing temperature, the amount of physically adsorbed substance decreases, and an increase in pressure leads to an increase in the amount of adsorption. The advantage of physical adsorption is the easy reversibility of the process.

Chemical adsorption is based on the chemical interaction between the adsorbent and the adsorbed substance. The forces acting in this case are much greater than during physical adsorption, and more heat is released. Gas molecules, having entered into chemical interaction with adsorbent molecules, are firmly held on the surface and in the pores of the adsorbent. It is characteristic that at low temperatures the rate of chemical adsorption is low, but it increases with increasing temperature.

Catalytic gas purification serves to convert impurities into harmless compounds. The process takes place on the surface of solid bodies - catalysts. The selection of catalysts is mainly decided empirically.

The catalysis process is greatly influenced by temperature. At relatively low temperatures, when the reaction rate is low compared to the rate of gas diffusion and the purification process is relatively slow. As the temperature rises, the rate of the chemical reaction increases, thereby increasing the rate of diffusion of gases. However, the diffusion rate increases more slowly and a moment may come when the gas purification process will be determined only by the rate of supply of reactants, and the use of the inner surface of the catalyst for this, as at the initial stage of the process, is close to zero. In this case, catalysis moves into the region of external diffusion. In this case, the small pores of the catalyst no longer play any role, but the role of the outer surface increases.

The most important characteristic of catalysts is the “ignition” temperature - the minimum temperature at which the catalyst begins to exhibit its properties.

Thermal oxidation of emission components is called oxidation at temperatures up to 1000°C. Oxidation is applied both to gases and to flammable components of the dispersed phase of aerosols. This method is used to extract resins, oils, volatile solvents and other components from gas streams. Of decisive importance in organizing the process is the preparation of gases for the reaction, i.e. heating the mixture to the required temperature and ensuring mixing of flammable gases with the oxidizer.

Sources of air pollution	Treatment plants	Note
Boiler house running on liquid fuel	Cyclone or cyclone battery Bag filters	Calculation clause 4.6 Calculation clause 4.7
Boiler house operating on gaseous fuel	Standalone offers	Description of the method
Solid fuel boiler room	Cyclone battery Bag filters	Calculation clause 4.6 Calculation clause 4.7
Painting and drying chamber	Adsorber	Calculation clause 4.8
Welding shop: welding production	Venturi scrubber (KMP gas scrubber)	Calculation clause 4.3
Mechanical shop: machine equipment	Dust settling chamber Cyclone CN	Calculation clause 4.2
Woodworking shop	Dust settling chamber Cyclone Giprodrevprom	Calculation clause 4.2 Calculation clause 4.6
Electroplating shop	Mesh mist eliminator	Calculation clause 4.4