Provide the classification of nuclear power plants in the world. Nuclear power plants

Nuclear power plants are, nuclear installations producing energy, while observing the specified modes under certain conditions. For these purposes, the territory defined by the project is used, where nuclear reactors are used in conjunction with the necessary systems, devices, equipment and structures to accomplish the assigned tasks. To carry out the target tasks, specialized personnel are involved.

All nuclear power plants in Russia

The history of nuclear energy in our country and abroad

The second half of the 40s was marked by the beginning of work on the creation of the first project involving the use of a peaceful atom to generate electricity. In 1948, I.V. Kurchatov, guided by the instructions of the party and the Soviet government, made a proposal to start work on the practical use of atomic energy to generate electricity.

Two years later, in 1950, not far from the village of Obninskoye, located in Kaluga region, the construction of the first nuclear power plant on the planet was started. The launch of the world's first industrial nuclear power plant, with a capacity of 5 MW, took place on June 27, 1954. The Soviet Union became the first power in the world that managed to use the atom for peaceful purposes. The station was opened in Obninsk, which had received the status of a city by that time.

But Soviet scientists did not stop there, they continued work in this direction, in particular, only four years later, in 1958, the operation of the first stage of the Siberian nuclear power plant began. Its capacity was several times higher than the station in Obninsk and amounted to 100 MW. But for domestic scientists this was not the limit, upon completion of all work, the design capacity of the station was 600 MW.

In the open spaces Soviet Union, the construction of a nuclear power plant, took on a massive scale at that time. In the same year, construction was launched Beloyarsk NPP, the first stage of which, already in April 1964, supplied the first consumers. The geography of the construction of nuclear power plants enveloped the whole country with its network, in the same year the first unit of the nuclear power plant in Voronezh was launched, its capacity was 210 MW, the second unit, launched five years later in 1969, could boast of a capacity of 365 MW. the boom in the construction of nuclear power plants did not subside throughout Soviet era... New stations, or additional blocks of those already built, were launched at intervals of several years. So, already in 1973, Leningrad received its own nuclear power plant.

However, the Soviet state was not the only one in the world who was able to master such projects. In Great Britain, they also did not doze and, realizing the prospects this direction, have actively studied this issue. After only two years, the British launched the opening of the station in Obninsk own project on the development of the peaceful atom. In 1956, in the town of Calder Hall, the British launched their own station, the capacity of which exceeded the Soviet analogue and amounted to 46 MW. They did not lag behind on the other side of the Atlantic, a year later, the Americans solemnly put into operation the station in Shippingport. The facility's capacity was 60 MW.

However, the development of a peaceful atom concealed hidden threats, which the whole world soon learned about. The first sign was a major accident in Three Mile Island that occurred in 1979, well, after which a catastrophe struck the whole world, in the Soviet Union, in the small town of Chernobyl, a large-scale disaster occurred, it happened in 1986. The consequences of the tragedy were irreparable, but besides this, this fact made the whole world think about the advisability of using nuclear energy for peaceful purposes.

The world's luminaries in this industry are seriously thinking about improving the safety of nuclear facilities. The result was the holding of a constituent assembly, which was organized on 05/15/1989 in the Soviet capital. The assembly decided to create a World Association, which should include all operators of nuclear power plants, its generally recognized abbreviation is WANO. In the course of implementing its programs, the organization systematically monitors the increase in the safety level of nuclear power plants in the world. However, despite all the efforts made, even the most modern and seemingly safe facilities cannot withstand the onslaught of the elements. It is because of the endogenous catastrophe, which manifested itself in the form of an earthquake and the ensuing tsunami in 2011, that an accident occurred at the Fukushima-1 station.

Atomic blackout

NPP classification

Nuclear power plants are classified according to two criteria, the type of energy they produce and the type of reactors. Depending on the type of reactor, the amount of generated energy, the level of safety, and also what kind of raw materials are used at the station are determined.

According to the type of energy that the stations produce, they are divided into two types:

Their main function is to generate electrical energy.

Nuclear thermal power plants. Due to the heating installations installed there, using heat losses that are inevitable at the station, it becomes possible to heat the network water. Thus, these stations generate heat energy in addition to electricity.

Having examined many options, scientists have come to the conclusion that the most rational are their three varieties, which are currently used all over the world. They differ in a number of ways:

1. Fuel used;
2. Applied heat carriers;
3. Active zones operated to maintain the required temperature;
4. A type of moderator that determines the decrease in the speed of neutrons that are released during decay and are so necessary to support the chain reaction.

The most common type is a reactor that uses enriched uranium as fuel. Ordinary or light water is used here as a heat carrier and moderator. Such reactors are called light-water reactors, there are two types of them. In the first, steam used to rotate the turbines is generated in a core called a boiling point reactor. In the second, the formation of steam occurs in an external circuit, which is connected to the first circuit by means of heat exchangers and steam generators. This reactor, began to develop in the fifties of the last century, the basis for them was the US army programs. In parallel, at about the same time, a boiling-water reactor was developed in the Union, in which a graphite rod acted as a moderator.

It is the type of moderated reactor of this type that has found practical application. This is a gas-cooled reactor. Its history began in the late forties, early fifties of the XX century, initially developments of this type were used in the production of nuclear weapons. In this regard, two types of fuel are suitable for it, these are weapons-grade plutonium and natural uranium.

The last project, which was accompanied by commercial success, was a reactor where heavy water is used as a coolant, and the already well-known natural uranium is used as a fuel. Initially, such reactors were designed by several countries, but in the end their production was concentrated in Canada, which is due to the presence of massive uranium deposits in this country.

Thorium NPPs - Energy of the Future?

The history of improving the types of nuclear reactors

The reactor, the first nuclear power plant on the planet, was a very reasonable and viable design, which was proved during the many years and flawless operation of the station. Among its constituent elements were distinguished:

1. side water protection;
2. masonry casing;
3. top floor;
4. prefabricated collector;
5. fuel channel;
6. top plate;
7. graphite masonry;
8. bottom plate;
9. distribution manifold.

The main structural material for fuel element cladding and technological channels was chosen stainless steel At that time, it was not known about zirconium alloys that could be suitable for working with temperatures of 300 ° C. Cooling of such a reactor was carried out with water, while the pressure under which it was supplied was 100 at. At the same time, steam was released with a temperature of 280 ° C, which is a quite moderate parameter.

The channels of the nuclear reactor were designed in such a way that they could be completely replaced. This is due to the limitation of the resource, which is due to the time spent by the fuel in the zone of activity. The designers did not find any reason to expect that structural materials located in the irradiated zone of activity will be able to use up their entire resource, namely about 30 years.

As for the TVEL design, it was decided to adopt a tubular version with a one-way cooling mechanism.

This reduced the likelihood that fission products would enter the circuit in the event of fuel rod damage. To regulate the temperature of the fuel element cladding, a fuel composition of a uranium-molybdenum alloy was used, which had the form of grains dispersed by means of a warm-water matrix. The nuclear fuel processed in this way made it possible to obtain highly reliable fuel rods. which were able to operate at high thermal loads.

The infamous Chernobyl nuclear power plant can serve as an example of the next round of development of peaceful nuclear technologies. At that time, the technologies used in its construction were considered the most advanced, and the type of reactor was the most modern in the world. We are talking about the RBMK-1000 reactor.

The thermal power of one such reactor reached 3200 MW, while it has two turbine generators, the electric power of which reaches 500 MW, thus, one power unit has an electric power of 1000 MW. Enriched uranium dioxide was used as fuel for the RBMK. In the initial state, before the start of the process, one ton of such fuel contains about 20 kg of fuel, namely uranium - 235. With a stationary loading of uranium dioxide into the reactor, the mass of the substance is 180 tons.

But the loading process is not a heap; fuel elements, already well-known to us fuel elements, are placed in the reactor. In fact, they are tubes that are made with a zirconium alloy. As the contents, they contain uranium dioxide tablets, which have a cylindrical shape. In the reactor activity zone, they are placed in fuel assemblies, each of which combines 18 fuel rods.

There are up to 1,700 such assemblies in such a reactor, and they are placed in a graphite stack, where vertical technological channels are specially designed for these purposes. It is in them that the circulation of the coolant takes place, the role of which, in the RMBK, is played by water. The whirlpool of water occurs under the influence of circulation pumps, of which there are eight. The reactor is located inside the shaft, and the graphic masonry is in a cylindrical body 30mm thick. The support of the entire apparatus is a concrete base, under which there is a pool - a bubbler, which serves to localize the accident.

The third generation of reactors uses heavy water

The main element of which is deuterium. The most common design is called CANDU, it was developed in Canada and is widely used around the world. The core of such reactors is located in a horizontal position, and cylindrical tanks play the role of a heating chamber. The fuel channel runs through the entire heating chamber, each of these channels has two concentric tubes. There are outer and inner tubes.

In the inner tube, the fuel is under the pressure of the coolant, which makes it possible to additionally refuel the reactor during operation. D20 heavy water is used as a retarder. In the course of a closed cycle, water is pumped through the pipes of the reactor containing the fuel bundles. As a result of nuclear fission, heat is generated.

The cooling cycle when using heavy water consists in passing through steam generators, where ordinary water boils from the heat generated by the heavy water, as a result of which steam is formed, escaping under high pressure. It is distributed back to the reactor, resulting in a closed cooling cycle.

It was along this path that there was a step-by-step improvement of the types of nuclear reactors that were used and are used in various countries of the world.

Basically, the division of power plants into IES, CHPP, CCGT, GTES, NPP, HPP is currently used. For a more complete description, power plants can be classified according to a number of main characteristics:

By the type of primary energy resources;

Energy conversion processes;

By the number and type of energy carriers;

By types of supplied energy;

By the circle of consumers covered;

According to the mode of operation.

1. According to the types of primary energy resources used, power plants are distinguished using: fossil fuel (TPP); nuclear fuel (NPP); hydropower (HPP, PSPP and TPP); solar energy (SES); wind energy (WPP); underground heat (geothermal GEOES).

2. According to the applied energy conversion processes, power plants are distinguished in which: the received thermal energy is converted into mechanical energy, and then into electrical energy (TPP. NPP); the obtained thermal energy is directly converted into electrical energy (power plants with MHD generators, MHD-ES, SES with photocells, etc.); the energy of water and air is converted into mechanical energy of rotation, then into electrical energy (hydroelectric power plant, pumped storage power plant, tidal power plant, wind power wind power plants, air-storage gas turbine power plants).

3. By the number and type of energy carriers used, power plants differ: with one energy carrier (IES and CHPP, nuclear IES and CHPP on steam, NPP with a gas energy carrier, GTPP); with two energy carriers of different phase states (combined-cycle power plants, including PG-KES and PG-CHP); with two different energy carriers of the same phase state (binary power plants).

4. According to the types of supplied energy, power plants differ: supplying only or mainly electrical energy (HPP, PSPP, IES, nuclear IES, GTES, PG-IES, etc.); supplying electric and thermal energy (CHP, nuclear CHP, GT-CHP, etc.). v Lately IES and nuclear IESs are increasingly increasing the supply of thermal energy. Combined heat and power plants (CHP), in addition to electricity, generate heat; The use of waste heat in cogeneration provides significant fuel savings. If exhaust steam or hot water is used for technological processes, heating and ventilation of industrial enterprises, then CHP plants are called industrial. When heat is used for heating and hot water supply of residential and public buildings in cities, CHPs are called communal (heating) plants. Industrial heating CHP plants supply heat as industrial enterprises and the population. At heating CHPPs, along with heating turbine plants, there are hot water boilers for supplying heat during periods of heat load peaks.

5. According to the range of consumers covered, the following are distinguished: regional power plants (GRES –state regional power plant); local power plants for power supply of individual settlements; block stations for power supply of individual consumers.

6. Power plants differ according to the mode of operation in EPS: basic; maneuverable or semi-peak; peak.

The first group includes large, most economical IESs, nuclear IESs, combined heat and power plants in heating mode and partially hydroelectric power plants, the second group includes flexible condensing power plants, SG-IES and CHPPs, and the third group includes peak hydroelectric power plants, hydroelectric power plants, and gas turbine power plants. Thermal power plants and less economical IESs operate partially in peak mode.

In addition to the above general basic features of the classification of power plants, each type has its own internal classification features. For example, IES and CHPP differ in their initial parameters, technological scheme(block and cross-linked), unit cardinality, etc. NPPs are classified by the type of reactors (thermal and fast neutrons), by the design of the reactors, etc.

Along with the main types of power plants discussed above, combined-cycle and purely gas-turbine power plants are also being developed in Russia. Combined-cycle power plants (PGPP) are used in two versions: with a high-pressure steam generator and with discharge of exhaust gases into conventional boiler units. In the first variant, combustion products from the combustion chamber under pressure are sent to a high-pressure compact steam generator, where high-pressure steam is generated, and the combustion products are cooled to 750-800 ° C, after which they are sent to a gas turbine, and high-pressure steam is supplied to a steam turbine.

In the second option, the combustion products from the combustion chamber with the addition of the required amount of air to reduce the temperature to 750-800 ° C are sent to the gas turbine, and from there exhaust gases at a temperature of about 350-400 ° C with a high oxygen content are fed into conventional boilers of steam turbine TPPs, where they perform the function of an oxidizer and give off their warmth.

And the first scheme should burn natural gas or a special gas turbine liquid fuel, in the second scheme such fuel should be burned only in the combustion chamber of a gas turbine, and in boilers - fuel oil or solid fuel, which is a definite advantage. The combination of the two cycles will increase the overall efficiency of the CHPP by about 5-6% compared to the steam-turbine IES. Power gas turbines The combined-cycle power plant accounts for approximately 20-25% of the capacity of the combined-cycle unit. Due to the fact that the specific capital investments in the gas turbine section are lower than in the steam turbine section, the SGPP achieves a decrease in specific capital investments by 10-12%. Combined cycle units are more maneuverable than conventional condensing units, and can be used to operate in the semi-peak zone, as they are more economical than maneuverable IESs.

Principles of classification of power plants. Classes, subclasses, groups, subgroups.

Classification of power plants

PART TWO

POWER PLANTS,
WORKING ON
FREE ENERGY

Class- is determined by the main process and the type of initial (consumed) energy.

Subclass- determined by characteristic features and accepted (familiar) names.

Group- is determined by the type of produced (generated) energy.

Subgroup- determines the type of installation by design differences.

Depending on the specific features and state of development, the specified division may not always be strictly observed. There are eight main classes:

1- thermal power plants: in them, the main process of energy release is a phase transition of a higher kind (FPVR), that is, partial or complete splitting of atoms into elementary particles - electrino and electrons. The initial energy is the potential binding energy of elementary particles in an atom - the energy accumulated in matter.

2- natural power plants, that is, plants that use energy natural phenomena directly.

3- coriolis power plants - the main process of energy production is associated with the self-spinning of the rotor by Coriolis forces. The initial energy of the radial flow of matter can be different: hydraulic, chemical, magnetic, ...

4- electromagnetic power plants - the main process is the conversion of electrino flows into different kinds energy: mechanical, thermal, electrical.

5- vibration resonance power plants - the main process is the energy exchange of the working fluid under conditions of vibration resonance. The source is energy external environment, in particular, molecules of atmospheric air.

6- ethereal power plants - the main process is the directional thickening of the ether, in particular, of the electric gas. The initial energy is ether.

7- rechargeable power plants - the main process is the accumulation of energy (electrical, chemical, thermal, ...) and its return when the battery is discharged.

8- combined power plants - installations with several different types of energy release processes, which are difficult to attribute to one of the specified classes.

This class includes all traditional power plants for fossil fuels, nuclear, hydrogen and new natural energy installations.

The traditional ones include: internal and external combustion engines, gas and steam turbine installations, as well as various thermal and boiler installations.

Nuclear power plants include modern nuclear power and heat plants, where the process of energy release goes with the complete decay of radioactive substances.

Hydrogen power plants use hydrogen, which reacts with oxygen to produce water.

The listed power plants are well known and there is a lot of technical literature on them, so there is no need to describe them in detail.

It should be emphasized that they use limited Natural resources: coal, oil, gas, uranium ..., not replenished by nature as quickly as they are spent. These installations are characterized by a flawed ecology, harmful to humanity.

Natural energy installations / 1 / free from these shortcomings, since only partial, gentle, decomposition of the substance (air, water) is used without change chemical properties due to a small mass defect of the order of 10 -6%, which is replenished in natural conditions.

Thermonuclear power plants, which have been under development for several decades with zero results, were not included in the classification, since in accordance with the modern theory / 1,2 / they are inoperative.

Reactors are classified according to the energy level of neutrons participating in the fission reaction, according to the principle of placement of fuel and moderator, purpose, type of moderator and coolant, and their physical state.

Nuclear reactors are divided into several groups:

1) Depending on the average energy of the neutron spectrum - into fast, intermediate and thermal;

2) According to the design features of the core - into hull and channel;

3) By the type of heat carrier - water, heavy water, sodium;

4) By the type of moderator - for water, graphite, heavy water, etc.

For energy purposes, for the production of electricity, the following are used:

1) Water-cooled reactors with non-boiling or boiling water under pressure,

2) Uranium-graphite reactors with boiling water or cooled with carbon dioxide,

3) Heavy water channel reactors, etc.

In the future, fast neutron reactors cooled by liquid metals (sodium, etc.) will be widely used; in which we fundamentally implement the fuel reproduction mode, i.e. creating the number of fissile isotopes of plutonium Pu-239 exceeding the number of consumed isotopes of uranium U-235. The parameter that characterizes the breeding of fuel is called the plutonium ratio. It shows how many acts of Pu-239 atoms are created during neutron capture reactions in U-238 per atom of U-235, which captured a neutron and underwent fission.

V thermal reactor most of the fission of nuclei occurs when nuclei absorb thermal neutrons from fissile isotopes. Reactors in which nuclear fission is carried out mainly by neutrons with an energy of more than 0.5 MeV are called fast neutron reactors. Reactors in which most of the fission occurs as a result of the absorption of intermediate neutrons by fissile isotopes nuclei are called intermediate (resonance) neutron reactors.

At present, thermal reactors are the most widely used. Thermal reactors are characterized by the concentration of 235 U nuclear fuel in the core from 1 to 100 kg / m 3 and the presence of large masses of the moderator. A fast neutron reactor is characterized by a nuclear fuel concentration of 235 U or 239 U of the order of 1000 kg / m 3 and the absence of a moderator in the core.

In reactors on intermediate neutrons in the active zone of the moderator is very small, and the concentration of nuclear fuel 235 U in it is from 100 to 1000 kg / m 3.

In thermal reactors, fission of fuel nuclei also occurs when fast neutrons are captured by the nucleus, but the probability of this process is insignificant (1 - 3%). The need for a neutron moderator is due to the fact that the effective fission cross sections of the fuel nuclei are much larger at low neutron energies than at large ones.

In the core of a thermal reactor there must be a moderator - a substance whose nuclei have a small mass number. Graphite, heavy or light water, beryllium, organic liquids are used as moderators. A thermal reactor can even run on natural uranium if heavy water or graphite is used as a moderator. For other moderators, enriched uranium must be used. The required critical dimensions of the reactor depend on the degree of fuel enrichment; with an increase in the degree of enrichment, they are smaller. A significant drawback of thermal reactors is the loss of slow neutrons as a result of their capture by the moderator, coolant, structural materials, and fission products. Therefore, in such reactors it is necessary to use substances with small capture cross sections for slow neutrons as a moderator, coolant, and structural materials.

The three essential elements for thermal reactors are the heat release, the moderator, and the coolant. This figure shows a typical core layout.

A coolant is pumped through the reactor with the help of pumps (called circulation pumps), which then flows either to the turbine (in RBMK) or to the heat exchanger (in other types of reactors). The heated coolant of the heat exchanger enters the turbine, where it loses part of its energy to generate electricity. From the turbine, the coolant enters the condenser for steam, so that the coolant with the parameters required for optimal operation is supplied to the reactor. The reactor also has a control system for it, which consists of a set of rods with a diameter of several centimeters and a length comparable to the height of the core, consisting of a material highly absorbing neutrons, usually boron compounds. The rods are located in special channels and can be raised or lowered into the reactor. In the raised state, they contribute to the acceleration of the reactor, in the lowered state, they drown it. The rod drives are independently adjustable, so they can be used to configure the reaction activity in different parts of the core.

The peculiarity of a nuclear reactor is that 94% of the fission energy is converted into heat instantly, i.e. during the time during which the power of the reactor or the density of materials in it does not have time to change noticeably. Therefore, when the reactor power changes, the heat release follows without delay the fuel fission process.

However, when the reactor is turned off, when the fission rate decreases by more than tens of times, the sources of delayed heat release (gamma and beta radiation from fission products) remain in it, which become predominant. The residual heat release after the termination of the fission reaction requires the removal of heat for a long time after the shutdown of the reactor. Although the power of the residual heat release is much less than the nominal one, the circulation of the coolant through the reactor must be ensured very reliably, since the residual heat release cannot be controlled. Removal of the coolant from the reactor that has been operating for some time is strictly prohibited in order to avoid overheating and damage to the fuel elements.

V intermediate neutron reactors, in which most fission events are caused by neutrons with energies higher than thermal (from 1 eV to 100 keV), the moderator mass is less than in thermal reactors. A specific feature of the operation of such a reactor is that the fission cross section of the fuel with an increase in neutron fission in the intermediate region decreases weaker than the absorption cross section of structural materials and fission products. Thus, the likelihood of acts of fission increases compared to acts of takeover. Requirements for neutron characteristics of structural materials are less stringent, their range is wider. Consequently, the core of an intermediate neutron reactor can be made of more durable materials, which makes it possible to increase the specific heat removal from the heating surface of the reactor. The enrichment of fuel with a fissile isotope in intermediate reactors due to a decrease in the cross section should be higher than in thermal reactors. Reproduction of nuclear fuel in reactors using intermediate neutrons is greater than in a reactor using thermal neutrons.

A substance that weakly moderates neutrons is used as a coolant in intermediate reactors. For example, liquid metals. The moderator is graphite, beryllium, etc.

Fuel elements with highly enriched fuel are placed in the core of a fast neutron reactor. The core is surrounded by a breeding zone consisting of fuel elements containing fuel feedstock (depleted uranium, thorium). Neutrons escaping from the core are captured in the breeding zone by the nuclei of the fuel raw material, resulting in the formation of new nuclear fuel. A special advantage of fast reactors is the possibility of organizing an extended breeding of nuclear fuel in them, i.e. simultaneously with the generation of energy, to produce new instead of burned-out nuclear fuel. Fast reactors do not require a moderator, and the coolant must not slow down the neutrons.

Reactors are divided into homogeneous and heterogeneous depending on the method of fuel placement in the core.

V homogeneous reactor nuclear fuel, coolant and moderator (if any) are thoroughly mixed and are in the same physical state, i.e. the core of a completely homogeneous reactor is a liquid, solid or gaseous homogeneous mixture of nuclear fuel, coolant or moderator. Homogeneous reactors can be both thermal and fast neutrons. In such a reactor, the entire core is located inside a steel spherical vessel and is a liquid homogeneous mixture of fuel and moderator in the form of a solution or liquid alloy (for example, a solution of uranyl sulfate in water, a solution of uranium in liquid bismuth), which also serves as a coolant.

A nuclear fission reaction occurs in a fuel solution inside a spherical reactor vessel, as a result, the solution temperature rises. The combustible solution from the reactor enters the heat exchanger, where it gives off heat to the water in the secondary circuit, is cooled and is sent back to the reactor by a circular pump. In order to prevent a nuclear reaction from occurring outside the reactor, the volumes of the pipelines of the loop, heat exchanger and pump are selected so that the volume of fuel in each section of the loop is much lower than the critical one. Homogeneous reactors have several advantages over heterogeneous ones. This is a simple design of the core and its minimum dimensions, the ability to continuously remove fission products and add fresh nuclear fuel during operation without stopping the reactor, the simplicity of fuel preparation, and also the fact that the reactor can be controlled by changing the concentration of nuclear fuel.

However, homogeneous reactors also have serious disadvantages. The homogeneous mixture circulating around the loop emits strong radioactive radiation, which requires additional protection and complicates the control of the reactor. Only part of the fuel is in the reactor and is used to generate power, while the other part is in external pipelines, heat exchangers and pumps. The circulating mixture causes severe corrosion and erosion of the systems and devices of the reactor and circuit. The formation of an explosive explosive mixture in a homogeneous reactor as a result of water radiolysis requires devices for its afterburning. All this led to the fact that homogeneous reactors were not widely used.

V heterogeneous reactor the fuel in the form of blocks is placed in the moderator, i.e. fuel and moderator are spatially separated.

Currently, only heterogeneous reactors are designed for energy purposes. Nuclear fuel in such a reactor can be used in gaseous, liquid and solid states. However, now heterogeneous reactors operate only on solid fuels.

Depending on the moderating agent, heterogeneous reactors are divided into graphite, light-water, heavy-water, and organic. By the type of coolant, heterogeneous reactors are light-water, heavy-water, gas and liquid metal. Liquid coolants inside the reactor can be in single-phase and two-phase states. In the first case, the coolant inside the reactor does not boil, and in the second, it boils.

Reactors in the core of which the temperature of the coolant is lower than the boiling point are called pressurized water reactors, and the reactors inside which the coolant boils are called boiling reactors.

Depending on the moderator and coolant used, heterogeneous reactors are designed according to different schemes. In Russia, the main types of nuclear power reactors are pressurized-water and water-graphite.

By design, reactors are subdivided into pressure vessel and channel reactors. V pressurized reactors the pressure of the coolant is carried by the body. The general flow of the coolant flows inside the reactor vessel. V channel reactors the coolant is supplied to each channel with the fuel assembly separately. The reactor vessel is not loaded with the coolant pressure; this pressure is carried by each separate channel.

Depending on the purpose, nuclear reactors are power, converters and breeders, research and multipurpose, transport and industrial.

Nuclear power reactors are used to generate electricity at nuclear power plants, in ship power plants, at nuclear combined heat and power plants (ATEC), as well as at nuclear power plants (AST).

Reactors designed for the production of secondary nuclear fuel from natural uranium and thorium are called converters or breeders... In the reactor - converter of secondary nuclear fuel, less of the initially consumed fuel is formed. In the breeder reactor, an extended breeding of nuclear fuel is carried out, i.e. it turns out more than it was spent.

Research reactors are used to study the processes of interaction of neutrons with matter, study the behavior of reactor materials in intense fields of neutron and gamma radiation, radiochemical and biological research, production of isotopes, experimental research of the physics of nuclear reactors. The reactors have different capacities, stationary or pulse operation. The most widespread are pressurized-water research reactors using enriched uranium. The thermal power of research reactors varies over a wide range and reaches several thousand kilowatts.

Multipurpose reactors are called that serve several purposes, for example, to generate power and obtain nuclear fuel.

Federal Agency for Education

GOU VPO “Pomor State University named after M.V. Lomonosov "

Faculty of Technology and Entrepreneurship

Lesson outline

on the topic: “Nuclear Power Plant”.

Arkhangelsk 2010

Lesson outline outline

Lesson topic. Nuclear power plants.

Lesson objectives:

1) Educational:

Introduce general information about nuclear power plants;

To reveal the main significance of the individual elements of the arrangement of nuclear power plants;

To acquaint with the advantageous locations of nuclear power plants;

Talk about the advantages and disadvantages of nuclear power plants;

To acquaint students with the latest data on the construction of nuclear power plants in the Arkhangelsk region.

2) Educational:

Cultivate attentiveness, perseverance, accuracy.

3) Developing:

Formation of cognitive interest in the subject;

Develop voluntary attention, visual memory, constructive thinking.

Lesson type: lecture using multimedia technologies.

Teaching aids, supplies and materials: structural diagram of a nuclear power plant.

For teacher- textbook; study tables and chalk for working on the blackboard, equipment for displaying multimedia.

For the student- textbook, squared notebook, workbook.

During the classes

Organizational part - 2 minutes

Greetings;

Checking readiness for the lesson;

Checking the attendance of students.

Message topic, lesson objectives - 3 minutes

Drawing the attention of the students to the blackboard, the teacher says out loud what has been written and asks them to write down the topic of the lesson in their student notebook.

Repetition of the previously covered material on the topic "Getting electricity" - 5 minutes

In order to save time on lectures, consolidation of the studied material with students is best done using the frontal survey method. However, other forms and methods of updating students' knowledge can also be used.

Students are invited to answer the questions:

Ways to use electricity?

Types of generators?

Power transmission lines - power lines;

What power plants generate electricity?

Radioisotope energy sources.

Learning new material - 25 minutes

Incorporating multimedia made in MS Power Point in front of students.

Nuclear power plant(NPP) - a complex of technical structures designed to generate electrical energy by using the energy released during a controlled nuclear reaction (slide No. 1).

Story.

In the second half of the 40s, even before the end of work on the creation of the first atomic bomb (its test, as you know, took place on August 29, 1949), Soviet scientists began to develop the first projects for the peaceful use of atomic energy, the general direction of which immediately became electric power industry.

In 1948, at the suggestion of I.V. Kurchatov, and in accordance with the instructions of the party and government, the first work began on the practical application of atomic energy to generate electricity.

In May 1950, near the village of Obninskoye, Kaluga Region, work began on the construction of the world's first nuclear power plant.

The world's first nuclear power plant with a capacity of 5 MW was launched on June 27, 1954 in the USSR, in the city of Obninsk, located in the Kaluga region (slide No. 2).

On April 29, 2002, at 11.31 Moscow time, the reactor of the world's first nuclear power plant in Obninsk was permanently shut down. According to the press service of the Ministry of Atomic Energy of Russia, the station was stopped solely for economic reasons, since "maintaining it in a safe condition became more and more expensive every year."

The world's first nuclear power plant with a 5 MW AM-1 reactor (Atom Peaceful) gave industrial current on June 27, 1954 and opened the way for the use of atomic energy for peaceful purposes, having successfully operated for almost 48 years.

In 1958, the 1st stage of the Siberian NPP with a capacity of 100 MW (full design capacity of 600 MW) was put into operation. In the same year, the construction of the Beloyarsk industrial nuclear power plant began, and on April 26, 1964, the 1st stage generator gave current to consumers. In September 1964, Unit 1 of the Novovoronezh NPP with a capacity of 210 MW was launched. The second unit with a capacity of 350 MW was launched in December 1969. In 1973, the Leningrad NPP was launched.

Outside the USSR, the first industrial nuclear power plant with a capacity of 46 MW was commissioned in 1956 at Calder Hall (Great Britain). A year later, a 60 MW nuclear power plant was commissioned in Shippingport (USA).

At the beginning of 2004, there were 441 nuclear power reactors operating in the world, the Russian TVEL OJSC supplies fuel for 75 of them.

The largest nuclear power plant in Europe - Zaporizhzhya NPP... Energodar (Zaporizhzhya region, Ukraine), the construction of which began in 1980 and in the middle of 2008 there are 6 nuclear reactor with a total capacity of 5.7 Gigawatts.

Classification.

By type of reactors.

Nuclear power plants are classified according to the reactors installed on them:

Thermal reactors, using special moderators to increase the probability of neutron absorption by the nuclei of fuel atoms;

Light water reactors. Light water reactor - a nuclear reactor in which ordinary water H3O is used to slow down neutrons and / or as a coolant. Ordinary water, unlike heavy water, not only slows down, but also largely absorbs neutrons (according to the reaction 1H + n = ²D) .;

Graphite reactors;

Heavy water reactors. Heavy water nuclear reactor - a nuclear reactor that uses D2O - heavy water as a coolant and moderator. Due to the fact that deuterium has a smaller neutron absorption cross section than light hydrogen, such reactors have an improved neutron balance, which makes it possible to use natural uranium as fuel in power reactors or to use "extra" neutrons for the production of isotopes in the so-called. "Industrial";

Fast neutron reactors are a nuclear reactor that uses neutrons with energies> 105 eV to maintain a nuclear chain reaction. ;

Subcritical reactors using external sources of neutrons;

Fusion reactors. Controlled thermonuclear fusion (CTF) is the synthesis of heavier atomic nuclei from lighter ones in order to obtain energy, which, in contrast to explosive thermonuclear fusion (used in thermonuclear weapons), is of a controlled nature.

By the type of energy released.

According to the type of energy supplied, nuclear power plants can be divided into:

Nuclear power plants (NPP) designed to generate electricity only;

Nuclear combined heat and power plants (CHPP) generating both electricity and thermal energy;

Nuclear heat supply stations (AST) that generate only thermal energy;

However, all nuclear power plants in Russia have heating installations designed for heating network water.

3.3. Basic elements of a nuclear power plant

One of the main elements of a nuclear power plant is a reactor. In many countries of the world, they use mainly nuclear fission reactions of uranium U-235 under the influence of thermal neutrons. For their implementation in the reactor, in addition to fuel (U-235), there must be a neutron moderator and, naturally, a coolant that removes heat from the reactor. In VVER (pressurized water) reactors, ordinary pressurized water is used as a moderator and coolant. In RBMK reactors (high-power channel reactor), water is used as a coolant, and graphite is used as a moderator. In previous years, both of these reactors were widely used at nuclear power plants in the electric power industry.

The reactor and its servicing systems include: the reactor itself with biological shielding, heat exchangers, pumps or gas-blowing installations that circulate the coolant; circulation pipelines and fittings; devices for reloading nuclear fuel; special systems ventilation, emergency cooling, etc.

NPPs with fast neutron reactors (BN), which can be used to generate heat and electricity, as well as to reproduce nuclear fuel, are promising. The technological diagram of a power unit of such a nuclear power plant is shown in the figure. The BN-type reactor has an active zone where a nuclear reaction takes place with the release of a flux of fast neutrons. These neutrons act on elements from U-238, which is usually not used in nuclear reactions, and convert it into plutonium Pu-239, which can later be used at nuclear power plants as a nuclear fuel. The heat of a nuclear reaction is removed by liquid sodium and used to generate electricity.

Basic technological scheme of a NPP with a BN-type reactor:

a - the principle of the reactor core;

b - technological scheme:

1 - reactor; 2 - steam generator; 3 - turbine; 4 - generator; 5 - transformer; 6-turbine condenser; 7 - condensate (feed) pump; 8 - heat exchanger for sodium circuits; 9 - non-radioactive sodium pump; 10 - radioactive sodium pump (slide No. 3.4).

NPPs do not have flue gas emissions and do not have waste in the form of ash and slag. However, the specific heat release into the cooling water at the NPP is higher than at the TPP, due to the higher specific consumption of steam, and, consequently, the high specific consumption of cooling water. Therefore, at most new nuclear power plants, it is planned to install cooling towers, in which the heat from the cooling water is removed to the atmosphere.

An important feature of the possible impact of a nuclear power plant on environment is the need for the disposal of radioactive waste. This is done in special burial grounds, which exclude the possibility of radiation exposure to people. In order to avoid the influence of possible radioactive discharges of the nuclear power plant on people in case of accidents, special measures were taken to increase the reliability of equipment (duplication of safety systems, etc.), and a sanitary protection zone was created around the plant.

3.4. Operating principle

Scheme of operation of a nuclear power plant on a double-circuit pressurized water reactor (VVER) (slide No. 5).

The figure shows a diagram of the operation of a nuclear power plant with a double-circuit pressurized water power reactor. The energy released in the reactor core is transferred to the primary coolant. Further, the coolant is pumped into a heat exchanger (steam generator), where it heats the secondary circuit water to a boil. The resulting steam enters the turbines that rotate the electric generators. At the outlet of the turbines, the steam enters the condenser, where it is cooled by a large amount of water coming from the reservoir.

The pressure compensator is a rather complex and cumbersome design, which serves to equalize the pressure fluctuations in the circuit during the operation of the reactor, arising from the thermal expansion of the coolant. The pressure in the 1st circuit can reach 160 atmospheres (VVER-1000).

In addition to water, molten sodium or gas can also be used as a heat carrier in various reactors. The use of sodium makes it possible to simplify the design of the reactor core cladding (in contrast to the water circuit, the pressure in the sodium circuit does not exceed atmospheric), to get rid of the pressure compensator, but it creates its own difficulties associated with the increased chemical activity of this metal.

The total number of circuits may vary for different reactors, the diagram in the figure is shown for VVER (Water-to-Water Power Reactor) reactors. RBMK type reactors (High Power Channel Type Reactor) use one water loop, and BN reactors (Fast Neutron Reactor) use two sodium and one water loops.

If it is impossible to use a large amount of water for condensation of steam, instead of using a reservoir, the water can be cooled in special cooling towers (cooling towers), which, due to their size, are usually the most visible part of a nuclear power plant.

3.5. Advantages and disadvantages.

Advantages of nuclear power plants:

Lack of harmful emissions;

Emissions of radioactive substances are several times less than coal e. plants of similar capacity (ash from coal-fired TPPs contains a percentage of uranium and thorium sufficient for their profitable extraction);

A small amount of fuel used and the possibility of its reuse after processing;

High power: 1000-1600 MW per power unit;

Low cost of energy, especially heat.

Disadvantages of nuclear power plants:

Irradiated fuel is dangerous and requires complex and expensive reprocessing and storage measures;

Variable power operation is undesirable for thermal reactors;

The consequences of a possible incident are extremely grave, although its probability is rather low;

Large capital investments, both specific, per 1 MW of installed capacity for units with a capacity of less than 700-800 MW, and general ones, necessary for the construction of the station, its infrastructure, as well as in the event of possible liquidation.

Nuclear power plants in Russia.

Currently in Russian Federation 10 operating NPPs operate 31 power units with a total capacity of 23,243 MW, of which 15 pressurized water reactors - 9 VVER-440, 15 channel boiling reactors - 11 RBMK-1000 and 4 EGP-6, 1 fast neutron reactor.

The development of the draft Energy Strategy of Russia for the period up to 2030 provides for a 4-fold increase in electricity production at nuclear power plants.

3.7. NPP NPP-92 design.

The project was created within the framework of the state program "Environmentally friendly energy". It took into account the domestic experience in the creation and operation of the previous model of the reactor plant (V-320) at the Zaporizhzhya, Balakovo, South-Ukrainian and Kalinin NPPs and the latest world achievements in the design and operation of nuclear power plants. The adopted technical solutions make it possible to international classification refer NPP-92 to nuclear power plants of the III generation. This means that such a nuclear power plant possesses the most advanced safety technology as applied to modern evolutionary light-water reactors. When developing a project for a nuclear power plant, the designers focused on minimizing the role of the human factor (slide 6).

The implementation of this concept was carried out in two directions. First, the project includes passive safety systems. This term refers to systems that operate with virtually no external power supply and do not require operator intervention. Secondly, the concept of dual-use active safety systems has been adopted, which greatly reduces the likelihood of undetected failures.

The main advantage of the NPP-92 project is that the main safety functions are performed independently of each other by two systems that differ in their operating principle. The presence of a double protective shell (containment), if necessary, prevents the release of radioactive products to the outside and protects the reactor from such external influences as a blast wave or an aircraft crash. All this, together with an increase in the reliability of systems, a decrease in the probability of failure and a decrease in the role of the human factor, increases the safety level of nuclear power plants.

3.8. The project of a floating nuclear power plant in Severodvinsk.

The project of the world's first floating nuclear power plant has started. Russia has begun construction of a floating power plant in Severodvinsk at the Sevmash shipyard, the only shipyard in the country capable of performing such a task. The PAES will be named after Mikhail Lomonosov. It is planned to create a flotilla of seven floating nuclear power plants to provide electricity and fresh water to the northern regions of Russia and the island states of the Pacific region, as well as a dozen other countries that have previously shown interest in the idea of ​​Russian nuclear scientists.

“Today we are signing an agreement on the construction of a series of six power units of floating nuclear power plants. There is a demand for them not only in Russia, but also in the Asia-Pacific region, where they can be used for water desalination,” Kiriyenko says. The first block will be a kind of pilot project. It is based on the KLT40S low-power reactor, which, however, will not prevent it from supplying energy to the entire Sevmash and, moreover, meeting the demand of a number of foreign companies. Reactor installations were commissioned to be manufactured by the Experimental Design Bureau of Mechanical Engineering. Afrikantov, 80% of the project will be financed by Rosatom, the rest will be undertaken by Sevmash.

The cost of the entire project is conventionally designated at the level of $ 200 million, while the payback period of the nuclear power plant, according to experts' forecasts, will be no more than seven years. In order to imagine the scale of costs, it is enough to cite a few figures characterizing, let's say, different dimensions of the financial space in which the project is being implemented. So, in 2007, 2 billion 609 million rubles will be allocated for the construction of the floating power plant. The pilot unit is planned to be launched no later than in 3.8 years. Each station will be able to operate for 12-15 years without reloading the fuel. At least 12 countries that are experiencing a shortage of electricity to one degree or another will not mind using mobile charging services. For almost four years, 25 thousand people working at the Severodvinsk shipyard will work on the first floating power plant.

New information on this topic:

The State Atomic Energy Corporation Rosatom has agreed with the government on the transfer of the site for the construction of the Akademik Lomonosov floating nuclear power plant from Sevmash (Severodvinsk, Arkhangelsk Oblast) to Baltic Plant (St. Petersburg), the Rosenergoatom Concern press service reports.

“The decision was caused by the significant workload of the enterprise and the need to focus its efforts on the state defense order,” the message says.

As specified in the press release, Sevmash will be revoked the general contract for the construction of a low-power nuclear power plant and the manufacture and supply of a floating power unit. The entire volume of construction in progress and undeveloped cash will be returned to the customer - Rosenergoatom.

Earlier it was reported that the construction of the first in the Russian Federation floating nuclear power plant "Sevmashpredpriyatie" was supposed to be completed in 2010. The contract value is $ 200 million. It was assumed that the project is financed by 80% from Rosenergatom funds, another 20% - from Sevmash. The NPP was planned to be commissioned in 2011.

Baltiyskiy Zavod is the largest shipbuilding company in Russia. The United Industrial Corporation, which controls the plant, manages assets with a total value of around 9 billion euros.

The Sevmash shipbuilding complex is the largest shipyard in the Russian Federation for the construction of nuclear submarines for the Russian Navy. However, in last years the company is experiencing difficulties with financing, which negatively affects the fulfillment of existing orders. Therefore, it is possible that the decision to reorder the order for the construction of a floating nuclear power plant was caused, among other things, by the situation at Sevmash (slide 7).

Generalization and consolidation of knowledge- 5 minutes.

The teacher can consolidate the studied material by the method of frontal questioning of students. For these purposes, they can use, for example, the following questions:

What is a nuclear power plant?

(Nuclear power plant(NPP) - a complex of technical structures designed to generate electrical energy by using the energy released during a controlled nuclear reaction);

In what year and in what city was the first nuclear power plant launched?

(In 1954 in Obninsk);

What types of reactors are there?

(Thermal reactors; light water reactors; graphite reactors; heavy water reactors; fast reactors; subcritical reactors; thermonuclear reactors);

What is a floating power plant?

(Floating nuclear power plant)

Summing up the lesson - 5 minutes

General characteristics of the educational activities of students, the teacher's message about the achievement of the goals of the lesson; identification of deficiencies and ways to eliminate them. Reminding the attendants of their duties. The teacher thanks the students for educational and cognitive activities, finishes the lesson.

Bibliography:

http://ru.wikipedia.org/wiki/NPP;

http://www.ippe.ru/rpr/rpr.php

http://www.posternazakaz.ru/shop/category/570/82/

http://slovari.yandex.ru/dict/bse/article/00005/16200.htm

http://dic.academic.ru/dic.nsf/bse/65911/Atomic

http://forca.ru/info/spravka/aes.html

http://gelz.net/docs/news_every_day/plavajushhaja_ajes.html

http://www.gubernia.ru/index.php?option=com_content&task=view&id=368