NPP with reactors bn. Ballad about fast neutrons: the unique reactor of the Beloyarsk NPP. Great achievement of Russia

The unique Russian fast neutron reactor operating at the Beloyarsk nuclear power plant has been brought to a capacity of 880 megawatts, the press service of Rosatom reports.

The reactor operates at power unit No. 4 of the Beloyarsk NPP and is now undergoing scheduled testing of generating equipment. In accordance with the test program, the power unit maintains electric power at a level of at least 880 megawatts for 8 hours.

The power of the reactor is being raised in stages, in order to eventually obtain certification at the design power level of 885 megawatts based on the test results. At the moment, the reactor has been certified for a capacity of 874 megawatts.

Recall that two fast neutron reactors operate at the Beloyarsk NPP. Since 1980, the BN-600 reactor has been operating here - for a long time it was the only reactor of this type in the world. But in 2015, the phased launch of the second BN-800 reactor began.

Why is this so important and considered a historic event for the global nuclear industry?

Fast neutron reactors make it possible to implement a closed fuel cycle (at present, it is not implemented in the BN-600). Since only uranium-238 is "burned", after processing (the extraction of fission products and the addition of new portions of uranium-238), the fuel can be reloaded into the reactor. And since more plutonium is produced in the uranium-plutonium cycle than has decayed, the excess fuel can be used for new reactors.

Moreover, this method can process surplus weapons-grade plutonium, as well as plutonium and minor actinides (neptunium, americium, curium) extracted from the spent fuel of conventional thermal reactors (minor actinides currently represent a very dangerous part of radioactive waste). At the same time, the amount of radioactive waste in comparison with thermal reactors is reduced by more than twenty times.

Why, with all their merits, fast neutron reactors are not widely used? First of all, this is due to the peculiarities of their design. As mentioned above, water cannot be used as a coolant, since it is a neutron moderator. Therefore, in fast reactors, metals are mainly used in a liquid state - from exotic lead-bismuth alloys to liquid sodium (the most common option for nuclear power plants).

“In fast neutron reactors, thermal and radiation loads are much higher than in thermal reactors,” Mikhail Bakanov, chief engineer of the Beloyarsk NPP, explains to PM. - This leads to the need to use special structural materials for the reactor vessel and in-reactor systems. TVEL and TVS cases are not made of zirconium alloys, as in thermal reactors, but of special alloyed chromium steels, which are less susceptible to radiation ‘swelling’. On the other hand, for example, the reactor vessel is not subjected to loads associated with internal pressure - it is only slightly higher than atmospheric pressure.

According to Mikhail Bakanov, in the first years of operation, the main difficulties were associated with radiation swelling and cracking of the fuel. These problems, however, were soon resolved, new materials were developed - both for fuel and for fuel rod casings. But even now, campaigns are limited not so much by fuel burnup (which on BN-600 reaches 11%), but by the resource of materials from which fuel, fuel elements and fuel assemblies are made. Further operational problems were mainly associated with leakage of sodium in the secondary circuit, a reactive and flammable metal that reacts violently to contact with air and water: “Only Russia and France have a long experience in operating industrial power reactors on fast neutrons. Both we and the French specialists faced the same problems from the very beginning. We successfully solved them, from the very beginning providing special means for monitoring the tightness of the circuits, localizing and suppressing sodium leaks. And the French project turned out to be less prepared for such troubles, as a result, in 2009, the Phenix reactor was finally shut down.”

“The problems really were the same,” adds the director of the Beloyarsk NPP, Nikolai Oshkanov, “but they were solved here and in France in different ways. For example, when the head of one of the assemblies bent on Phenix to capture and unload it, French specialists developed a complex and rather expensive system of 'vision' through the sodium layer. And when we had the same problem, one of our engineers suggested using a video camera placed in the simplest design like a diving bell, - a pipe open from below with argon blowing from above. When the sodium melt was expelled, the operators were able to capture the mechanism via video link, and the bent assembly was successfully removed.”

The core of a fast neutron reactor is arranged like an onion, in layers

370 fuel assemblies form three zones with different enrichment in uranium-235 - 17, 21 and 26% (initially there were only two zones, but in order to equalize the energy release, they made three). They are surrounded by side screens (blankets), or breeding zones, where assemblies containing depleted or natural uranium, consisting mainly of the 238 isotope, are located. reproduction).

Fuel assemblies (FAs) are a set of fuel elements (TVELs) assembled in one housing - tubes made of special steel filled with uranium oxide pellets with various enrichment. So that the fuel elements do not touch each other, and the coolant can circulate between them, a thin wire is wound around the tubes. Sodium enters the fuel assembly through the lower throttling holes and exits through the windows in the upper part.

In the lower part of the fuel assembly there is a shank inserted into the collector socket, in the upper part there is a head part, by which the assembly is captured during reloading. Fuel assemblies of various enrichment have different seats, so it is simply impossible to install the assembly in the wrong place.

To control the reactor, 19 compensating rods containing boron (neutron absorber) are used to compensate for fuel burnup, 2 automatic control rods (to maintain a given power), and 6 active protection rods. Since uranium's own neutron background is small, for a controlled launch of the reactor (and control at low power levels) "backlight" is used - a photoneutron source (gamma emitter plus beryllium).

Power units with fast neutron reactors can significantly expand the fuel base of nuclear power and minimize radioactive waste through the organization of a closed nuclear fuel cycle. Only a few countries have such technologies, and the Russian Federation, according to experts, is the world leader in this field.

The BN-800 reactor (from "fast sodium", with an electric power of 880 megawatts) is a pilot industrial fast neutron reactor with a liquid metal coolant, sodium. It should become a prototype of commercial, more powerful power units with BN-1200 reactors.

sources

The newest power unit No. 4 of the Beloyarsk NPP with a BN-800 fast neutron reactor was put into commercial operation on time.

This is one of the most important events of the year in the Russian nuclear power industry, the press service of the Beloyarsk Nuclear Power Plant reports.

The order to this effect was signed on October 31, 2016 by Andrey Petrov, Director General of the Rosenergoatom Concern, on the basis of the permission received from Rosatom State Corporation. Prior to this, the regulatory body "Rostekhnadzor" carried out all the necessary checks, and issued a conclusion on the compliance of the facility being commissioned project documentation, technical regulations and regulatory legal acts, including energy efficiency requirements.

Power unit No. 4 of the Beloyarsk NPP with a BN-800 reactor was included in the country's unified energy system for the first time and began generating electricity on December 10, 2015. During 2016, there was a gradual development of power at the stages of power start-up, and then at the stages of pilot operation, checks and tests of equipment and systems were carried out at various power levels and in various operating modes.

The tests ended in August 2016 with a 15-day comprehensive test at 100% power level, during which the power unit confirmed that it was able to stably carry the load at rated power in accordance with the design parameters, without deviations.

By the time it was put into commercial operation, the fourth power unit of the Beloyarsk nuclear power plant had generated more than 2.8 billion kWh since its inclusion in the power system.

It should become a prototype of more powerful commercial power units BN-1200, the decision on the feasibility of building which will be made based on the experience of operating the BN-800. It will also work out a number of technologies for closing the nuclear fuel cycle, which are necessary for the development of nuclear energy in the future.

Russia, according to experts, ranks first in the world in the technology of building "fast" reactors.

Thus, in Russia there is one more nuclear power unit in operation. Now, a total of 35 power units are in operation at 10 nuclear power plants (excluding NVNPP power unit No. 6, which is at the stage of pilot operation), with a total installed capacity of all power units of 27.127 GW.

Beloyarsk NPP (BNPP) put into operation in April 1964. This is the first nuclear power plant in the country's nuclear power industry, and the only one with reactors of different types on the same site. The first power units of the Beloyarsk nuclear power plant with thermal neutron reactors AMB-100 and AMB-200 were shut down due to exhaustion. The only power unit in the world with a fast neutron reactor of industrial power level BN-600 is in operation , as well as BN-800, put into commercial operation in October 2016. Power units of nuclear power plants on fast neutrons are designed to significantly expand the fuel base of nuclear energy and minimize radioactive waste through the organization of a closed nuclear fuel cycle.

At the Beloyarsk NPP in the city of Zarechny, they are preparing to install a reactor for a new power unit. Currently, the BNPP operates the world's only power unit with a 600 MW fast neutron reactor (it is the most powerful in the Middle Urals), and now a new, even more powerful unit is being built. The correspondent of Nakanune.RU looked at how these works are going, and is ready to tell and show what the future nuclear reactor, which is being built at a nuclear power plant in Sverdlovsk region and what makes the technology used at the BNPP unique.

Nuclear power turned out to be one of those industries that the crisis did not affect in Russia. Well, almost never touched. Electricity generation at the country's nuclear power plants will remain at the same level, many of the problems that had to be faced in other areas do not exist. In addition, the builders, who were previously reluctant to build new facilities on a rotational basis, rushed back to the stations, because their construction is financed by the state. We visited one of these construction sites - the construction of the fourth power unit BN-800 of the Beloyarsk NPP.

BNPP Director Nikolai Oshkanov (he is also Deputy CEO Energoatom Concern, which unites ten nuclear power plants in the country) notes: "There is no crisis at Russian nuclear power plants - none of the crisis phenomena has affected us and will not affect us." However, he admits that the reduction in energy consumption also affected the nuclear industry - at some stations of the concern, the blocks were in reserve, but by June 1, it reached 100% of output.

At the BNPP, work continues on the construction of the BN-800 (the project is being implemented as part of the Federal Target Program for the development of nuclear energy in Russia). At present, the plant operates the only power unit in the world with an industrial-level fast neutron reactor BN-600 (this is the third power unit of the BNPP, the first two are in the process of being decommissioned). What is the peculiarity of the technology of "fast" reactors, says Nikolai Oshkanov himself:

"In the program (FTP for the development of nuclear energy, - ed.), the BNPP is represented by the fourth power unit as an innovative technology - this is a new step on which the whole world has rushed, and here Russia, using the example of the Beloyarsk NPP, turned out to be the leader. Only large countries - the United States, can afford it , France, Japan, Russia, England - that is, those who have a bomb. Not the DPRK, which stole the technology, but precisely those who can develop this direction. Why were "fast" reactors made? In a "fast" reactor, plutonium is obtained clean, weaponry.

At the BNPP, fuel is used for peaceful purposes, the technology allows expanding the country's fuel energy base and minimizing the amount of nuclear waste.

All uranium is divided into two parts: 0.7% is what can be used in reactors, 99.3% is the so-called "dump", it cannot be used in reactors that exist all over the world, including in our country. The "fast" reactor converts unused uranium-238 under the action of fast neutrons into plutonium-239," explains Nikolai Oshkanov.

So, after loading 10 tons of plutonium into the reactor, 12 tons are taken out of it, because the plutonium was "surrounded" by uranium, he notes. Thus, the uranium "dump" becomes fuel.

This technology has been used on the BN-600 since 1980, and the BN-800 is designed to solve the problem of a "closed" nuclear cycle, which ensures the "circulation" of fuel between fast and thermal neutron reactors.

Meanwhile, Nikolai Oshkanov at a press conference last Friday confirmed that the commissioning deadlines are being shifted from 2012 to 2014. The problem is not in the crisis, but in the equipment, he says.

This year, 2 billion rubles were spent on the construction of the facility, not counting the cost of equipment. “We are number three in the FTP. The second power unit of the Volgodonsk NPP is the first, followed by the fourth unit of the Kalinin NPP. This year, we were allocated almost 13 billion rubles, although 15 was originally planned, but those (power units) need to be put into the first turn, because there is no electricity in the Caucasus and in the Leningrad region," he said.

The main problem due to which the launch of the BN-800 is delayed is the problem with the manufacture of unique equipment. “The problem is in the equipment, it is unique, it has not been made for a long time, these are new technologies, materials. It was necessary to revive entire plants for the sake of one unit. All auxiliary equipment has been done, but there is no reactor with a turbine,” said the director of the BNPP.

However, if the work on the construction of the reactor is almost on schedule (it will be delivered to the station by the Podolsky plant named after Ordzhonikidze), then the main difficulty is in the manufacture of the turbine (the United Machine Plants is engaged in it).

We were able to verify that the workers are on schedule for the construction of the reactor (where the radioactive equipment will be located), we were able to verify in the reactor assembly vessel.

The building of the reactor assembly building was built back in the 80s, but then the construction of the BN-800 was stopped, and resumed only three years ago. Only in 2008 did the enlargement of the reactor begin - it comes from the plant in Podolsk in parts, explains Alexei Chernikov, deputy chief engineer of the Beloyarsk installation department.

As expected, the installation of the reactor in the mine will begin in August-September this year.

Meanwhile, as early as July 1, not entirely pleasant changes may await the nuclear industry. Starting from this date, the electric power industry is switching to a "50 to 50" work scheme: 50% of energy will be sold on the free market and 50% - at a fixed tariff. It has already been calculated that as a result, the payment for electricity to the population will increase. "There is a variant according to which the problem will be solved at the expense of nuclear energy," says Nikolai Oshkanov. Since the electricity generated by the nuclear industry is cheaper at cost, the "expenses" can be laid on this industry.

However, the director of the BNPP looks at the "nuclear future" in general with hope: "The world is witnessing a" nuclear renaissance "-" climbed "as in the old days, the construction of nuclear power plants, Russia builds in China, India, only in Europe it is" not allowed ". In Russia, the main problem is not resources, but their delivery."

"As the population asks, so it will be," he comments on the prospects for the industry, not hiding the further plans of the BNPP itself - already in 2020 they intend to start building the fifth power unit - BN-1200.

— one of the most influential and authoritative international professional publications in this field — awarded its Power Awards for 2016 to the project of the fourth power unit of the Russian Beloyarsk NPP with a unique BN-800 fast neutron reactor, which will test a number of technologies necessary for the development of nuclear energy .

This is not the first time Russian nuclear projects have received recognition in the United States. The completed first block of the Iranian nuclear power plant Bushehr and the first block of the Indian nuclear power plant Kudankulam were previously named projects of 2014 according to another authoritative American magazine Power Engineering. These power units operate Russian thermal reactors VVER-1000.

Great achievement of Russia

"Fast neutron reactors are essential for the implementation of Russia's ambitious plans in nuclear energy. The successful construction, inclusion in the network and testing of the country's first BN-800 reactor at the Beloyarsk NPP is a major achievement in the right direction," the magazine notes.

Block No. 4 of the Beloyarsk NPP with a fast neutron reactor with liquid metal sodium coolant BN-800 (from "fast sodium") with an installed electric power of 880 MW was put into commercial operation on Monday. It is the world's most powerful operating fast neutron reactor.

Experts called this event historical not only for Russian, but also for the world nuclear power industry. Experts emphasize that the experience of designing, building, launching and operating fast neutron power reactors, which Russian nuclear scientists will receive at the BN-800, will be necessary for the development of this area of ​​nuclear energy in Russia.

Recognized Leadership

Fast neutron reactors are considered to have great advantages for the development of nuclear energy, providing the closure of the nuclear fuel cycle (NFC). In a closed nuclear fuel cycle, due to the full use of uranium raw materials in fast breeder reactors (breeders), the fuel base of nuclear energy will increase significantly, and it will also be possible to significantly reduce the volume of radioactive waste due to the burning of hazardous radionuclides. Russia, according to experts, ranks first in the world in the technology of building "fast" reactors.

The Soviet Union was a leader in the construction and operation of "fast" power reactors of industrial power level. The world's first such unit with a BN-350 reactor with an installed electrical capacity of 350 megawatts was launched in 1973 on the eastern coast of the Caspian Sea in the city of Shevchenko (now Aktau, Kazakhstan). Part of the thermal power of the reactor was used to generate electricity, the rest went to desalination of sea water. This power unit worked until 1998 - five years longer than the design period. Experience in the creation and operation of this installation made it possible to understand and solve many problems in the field of BN-type reactors.

Since 1980, the third power unit of the station with the BN-600 reactor with an installed electrical capacity of 600 megawatts has been operating at the Beloyarsk NPP. This unit not only generates electricity, but also serves as a unique base for testing new structural materials and nuclear fuel.

History of the BN-800

In 1983, a decision was made to build in the USSR four nuclear units with the BN-800 reactor at once: one at the Beloyarsk NPP and three at the new South Ural NPP. But after Chernobyl, the stagnation of the Soviet nuclear power industry began, the construction of new, including "fast" reactors, ceased. And after the collapse of the USSR, the situation worsened even more, there was a threat of losing domestic nuclear energy technologies, including the technology of BN reactors.

Attempts to resume the construction of at least one BN-800 unit were made more than once, but in the middle of the 2000s it became clear that the capabilities of the nuclear industry alone might not be enough for this. And here the decisive role was played by the support from the Russian leadership, which approved a new program for the development of nuclear energy. It also found a place for the BN-800 at the fourth unit of the Beloyarsk NPP.

It was not easy to complete the block. To finalize the project, taking into account improvements, the purpose of which was to increase its efficiency and safety, a real mobilization of the forces of scientific, design and design organizations of the nuclear industry was required. Difficult tasks faced the equipment manufacturers, who had to not only restore the technologies by which the equipment of the BN-600 reactor was created, but also master new technologies.

And yet the power unit was built. In February 2014, loading of nuclear fuel into the BN-800 reactor began. In June of the same year, the reactor was launched. Then it was necessary to modernize the design of the fuel assemblies, and at the end of July 2015 the BN-800 reactor was restarted, specialists began to gradually increase its power to the level necessary to start generating electricity. On December 10, 2015, the unit was connected to the grid and gave out its first current to the Russian power system.

The BN-800 unit is to become a prototype of more powerful commercial power units BN-1200, the decision on the feasibility of building which will be made on the basis of BN-800 operating experience. The BN-1200 head unit is also planned to be built at the Beloyarsk NPP.