How the most powerful Russian nuclear power plants. Balakovo NPP
• How does the most powerful Russian nuclear power plants. Balakovo NPP
Balakovo NPP - Russia's largest producer of electricity - more than 30 billion kWh. annually, accounting for 1/5 of the production of all the country's nuclear power plants. Among the largest of all types of power plants in the world occupies 51st position. The first unit BalAES was included in the Unified Energy System of the USSR in December 1985, the fourth unit in 1993 became the first commissioned in Russia after the Soviet collapse.
Balakovo NPP is located on the left bank of the Saratov Reservoir of the Volga River, 10 km north-east of Balakovo, Saratov region. at a distance of approximately 900 kilometers southeast of Moscow.
Technical water, which is extremely important for VVER is performed by using a closed circuit cooling reservoir formed by clipping dams shallow part Saratov reservoir.
are exploited 4 standard unit with reactor installation, which includes VVER-1000 (VVER - 1,000 megawatts of electrical power, the body type thermal neutron light water as a moderator and coolant) at Balakovo - RU is the most common type in the world, foreign analogue is the acronym PWR.
units can estimate the scale of the "helicopter".
Each unit consists of a turbine and reactor compartments - forming a monoblock. Uninterrupted power supply of each unit provides for three independent electric stations reserve diesel type SDA-5600 (RDES - power 5, 6 megawatts).
The height of the top mark unit of the dome - 67, 5 meters.
Sealed containment shell is safety system intended to prevent the release of radioactive substances in serious accidents with major pipeline rupture of the first circuit and retention failure localization zone environment of high temperature and pressure. It has a cylindrical shape and is composed of prestressed concrete thickness of 1, 2 meters.
Get into the reactor compartment unit can only sanitary and domestic special building block for the transition overpass. The sanitary sanitary inspection unit are arranged to pass into the zone of ionizing radiation. Here plant staff fully disguised in protective clothing. After the release of the sanitary inspection in the controlled access zone personnel are on board to the radiation control duty Dosimetrists for personal dosimeters.
The inner door of the main civilian gateway to around 36 meters.
When working on the containment of the reactor plant capacity is closed - it is at a slight underpressure. To access the operating staff into the need to undergo the procedure of locking. Default gateway - a sophisticated device designed to ensure passage into geromoobema while maintaining the pressure difference between the containment and reactor compartment obstroykoy.
The central hall in the containment GO 2nd unit.
Containment is a cylinder inner diameter of 45 meters and a height of 52 m, with a mark of 13 2 m above ground level, where it is flat bottom, to the level of 66 to 35 m where the peak of its dome-shaped top.
Flow diagram of each block dual circuit. The first circuit is radioactive, it includes a VVER 3000 MW thermal input and four cooling circulation loop, which through the core via the main circulation pump is pumped coolant - water under a pressure of 16 MPa.
We go down to the reactor.
On Balakovo used modernized serial nuclear reactor with water VVER-1000 under pressure, which is designed to generate heat due to fission chain reaction of the atomic nuclei. Regulation of the reactor power by changing the position of the clusters in the active area of the rods with absorbing elements, the steel tubes with the boron carbide, and also by changing the boric acid concentration in water of the first circuit.
The nuclear reactor.
The water temperature at the inlet to the reactor is equal to 289 ° C, at the output - 320 ° C. The circulating water flow rate through the reactor is 84000 tons / h.
The heated water is directed into the reactor in four lines in the steam generators.
The steam generator - a horizontal heat exchanger immersed heat transfer surface adapted for generating dry vapor with productivity 1470t / h. The water from the reactor enters the manifold and is distributed into the tubes at 11,000. Passing through them, it gives up heat to boiler feed water of the second circuit and exits through a similar collecting manifold to a suction nozzle main circulation pump (MCP). Thus, the steam generator is the boundary between the first element - and the second circuit radioactive - nonradioactive.
The second circuit - non-radioactive, is the flash and vodopitatelnoy installations, block desalting unit and the turbine unit of electrical capacity of 1000 MW. Cooled primary coolant in steam generators, while giving heat to the water of the second circuit.
Saturated steam produced in the steam generator, with a pressure of 6, 4 MPa and a temperature of 280 ° C is fed into a collecting steam pipe and directed to the turbine, resulting in rotation of the generator.
Type boxing deep into the main circulation pump (MCP).
The forced circulation of the coolant due to the work carried out four main circulation pumps MCP-195M. Each of the MCP at a speed of 1000 rev / min. It provides pumping through the reactor core 21,000 tons of water per hour.
Pool wet overload nuclear fuel.
To maintain the normal operation of the reactor must perform refueling. refueling by installments, at the end of boric reactor fuel assemblies unloaded a third campaign, and the same number of fresh assemblies loaded in the core, for these purposes in the containment has a special refueling machine MPS-1000. Nuclear fuel for the Balakovo NPP produced Novosibirsk Chemical Concentrates Plant.
All the operations with the spent nuclear fuel (SNF) are performed remotely by a 3-meter layer of borated water. The spent fuel contains a large amount of uranium fission products. Nuclear fuel has the ability to self-heating to high temperatures and is highly radioactive, so it is stored for 3-4 years in the pools with temperature conditions of the water layer, which protects personnel from ionizing radiation. As exposure decreases radioactivity of the fuel and the power of its residual heat. Typically, after 3 years, when the self-heating of the fuel assembly is reduced to 50-60 ° C, it is removed and sent for storage, disposal or recycling.
Remote refueling machine control ICS-1000.
One of the most effective ways to increase electricity production - increasing duration of the nuclear reactor campaign, work in this direction were made on Balakovo many years. With the improvement of nuclear fuel designs move to 18-month fuel cycle it has become possible and is now gradually being implemented. The bottom line is that the refueling began to carry out at least once a year, with the full implementation of its overload will be performed again 1, 5 years, respectively, longer reactor operating non-stop, its energy output increases. At the moment the BNPP implemented campaign with a planned duration of 420-480 eff. days, which is a crucial stage in the transition to the 18-month fuel cycle.
In order to measure the temperature and pressure of the coolant inside the reactor vessel using sensors placed neutron measurement channels on the traverse unit protective tube reactor.
NDT performed planned control the weld and the base metal.
Total station employs about 3,770 people, more than 60% of which have higher or secondary vocational education.
Wrench main connector reactor VVER-1000.
Application wrench provides a seal assembly sealing simultaneous and uniform stretch pins reduces the time for carrying out works on compaction and decompaction reactor main connector, reduces labor costs and maintenance personnel as a consequence of their dosage load.
In the normal operation of the steam generator during the lifetime control is necessary to produce the heat exchange tube surfaces from deposits.
To control the state of the metal at the Balakovo NPP is used eddy current method of control (VTC).
Polar crane under the dome of the containment.
If the decompression and the first circuit techah water vaporization occurs, which is accompanied by increase in pressure by the containment dome. To reduce the vapor pressure therein is sprayed cold water.
overalls pollution measurement in sanitary gateway.
In areas obstroyki reactor department organized special additional radiation monitoring posts and sanitizing - sanitary locks. Staff coming from the work area or the location of the processing equipment passes obligatory monitored and, if necessary - washing and garment processing and the skin to prevent the spread of radioactive contamination in a clean room of permanent residence staff.
Block control room.
Personnel leads entire process (equipment operates and controls automatic work) with control room (MCR).
Conventionally, the control room is divided into three areas of responsibility. The first zone is directly operated by the Head Unit shift and includes supply and panel systems of safety system, the second zone - operated by the master control engineer reactor - it is monitored with reactor operation, the first circuit basic equipment and technological systems of the reactor compartment. The third zone - the responsibility of the lead engineer for turbine control.
Lead Engineer for the management of one of the turbine units.
In the control room of the power unit is controlled by more than 19,000 options.
All the steam produced by the steam-four power unit is combined and fed to the turbine.
The machine room with the turbo-generator.
Condensing steam turbine, single-shaft, four-cylinder (one high-pressure cylinder, three - low pressure).
Rated power 1000MVt, speed of 1500 rpm.
high pressure cylinder (CVP) for tripping "acute" steam from the main steam header.
The initial pressure in the housing 60 atmospheres, steam temperature 274 degrees.
On the same shaft as the turbine generator is mounted brand TIA-1000, the generated voltage of 24,000 volts.
Senior driver bypassed the turbine.
Issuance of electricity.
NPP electrical equipment as a whole is not very different from the thermal power stations, with the exception of increased requirements for reliability.
Power Output Balakovo through bus ORU-220/500 kV in the United grid Middle Volga.
The tires are in the power node and link Saratov grid with Maitland, Samara, Volgograd and Ural.
the water-cooling area 24, 1 km ² - a source of circulating water nuclear power plant.
Here live grass carp and silver carp, essential for natural biological cleansing and maintaining the quality of the water cooling pond.
The water from the cooler on open feeding channels supplied to the four block pumping stations (BNS) is located on its shore. These pump stations provide non-critical service water consumers.
For technical supply of responsible consumers (equipment, including emergency, break in the water supply which is not allowed in any operating mode), a special closed circulating system, which includes the spray ponds.
the water is cooled by the spray, which increases the heat transfer area.
The shield has demineralizer devices and control elements controls ensuring purification and desalination processes, dosing of the reactants in water treatment and so forth.
analytical laboratory designed to provide high reliability during the chemical analysis, processing and storage of databases for chemical reactors operating modes.
Laboratory equipped ionic chromatography, X-ray crystal diffraction spectrometer, moisture titrator, optical emission spectrometer with inductively coupled plasma, and so on. D.
We discuss the construction of the second stage of the station, consisting of the fifth and the sixth unit of the same design as the existing ones at the station.