Mobile nuclear power plants created in the USSR and Russia

2024 Author: Seth Attwood | [email protected]. Last modified: 2023-12-16 15:55

Soviet mobile nuclear power plants were intended primarily for work in remote areas of the Far North, where there are no railways and power lines.

In the dim light of a polar day on the snow-covered tundra, a column of tracked vehicles crawls in a dotted line: armored personnel carriers, all-terrain vehicles with personnel, fuel tanks and … four mysterious machines of impressive size, similar to mighty iron coffins. Probably, this or almost the way it would look like the journey of a mobile nuclear power plant to the N-military facility, which guards the country from a potential enemy in the very heart of the icy desert …

The roots of this story go, of course, to the era of atomic romance - in the mid-1950s. In 1955, Efim Pavlovich Slavsky, one of the leading figures of the USSR nuclear industry, the future head of the Ministry of Medium Machine Building, who served in this post from Nikita Sergeevich to Mikhail Sergeevich, visited the Leningrad Kirovsky plant. It was in a conversation with the director of the LKZ I. M. Sinev for the first time voiced a proposal to develop a mobile nuclear power plant that could supply electricity to civil and military facilities located in remote regions of the Far North and Siberia.

Slavsky's proposal became a guide to action, and soon LKZ, in cooperation with the Yaroslavl steam locomotive plant, prepared projects for a nuclear power train - a mobile nuclear power plant (PAES) of small capacity for transportation by rail. Two options were envisaged - a single-circuit scheme with a gas turbine installation and a scheme using a steam turbine installation of the locomotive itself. Following this, other enterprises joined in the development of the idea. Following the discussion, the green light was given to the project by Yu. A. Sergeeva and D. L. Broder from the Obninsk Institute of Physics and Power (now FSUE "SSC RF - IPPE"). Apparently considering that the rail version would limit the area of operation of the AES only to the territories covered by the railway network, the scientists proposed to put their power plant on tracks, making it almost all-terrain.

A draft design of the station appeared in 1957, and two years later, special equipment was produced for the construction of prototypes of TPP-3 (a transportable power plant).

In those days, practically everything in the nuclear industry had to be done "from scratch", but the experience of creating nuclear reactors for transport needs (for example, for the icebreaker "Lenin") already existed, and one could rely on it.

TPP-3 is a transportable nuclear power plant transported on four self-propelled tracked chassis based on the T-10 heavy tank. TPP-3 entered trial operation in 1961. Subsequently, the program was curtailed. In the 80s, the idea of transportable large-block nuclear power plants of small capacity received further development in the form of TPP-7 and TPP-8.

One of the main factors that the authors of the project had to take into account when choosing one or another engineering solution was, of course, safety. From this point of view, the scheme of a small-sized double-circuit pressurized water reactor was recognized as optimal. The heat generated by the reactor was taken away by water under a pressure of 130 atm at a temperature at the inlet to the reactor of 275 ° C and at the outlet of 300 ° C. Through the heat exchanger, heat was transferred to the working fluid, which also served as water. The generated steam drove the turbine of the generator.

The reactor core was designed in the form of a cylinder 600 mm in height and 660 mm in diameter. Inside were placed 74 fuel assemblies. It was decided to use an intermetallic compound (a chemical compound of metals) UAl3, filled with silumin (SiAl), as a fuel composition. The assemblies consisted of two coaxial rings with this fuel composition. A similar scheme was developed specifically for TPP-3.

In 1960, the created power equipment was mounted on a tracked chassis borrowed from the last Soviet heavy tank T-10, which was produced from the mid-1950s to the mid-1960s. True, for the PAES the base had to be lengthened, so that the power self-propelled gun (as they began to call all-terrain vehicles transporting a nuclear power plant) had ten rollers against seven for the tank.

But even with such modernization, it was impossible to accommodate the entire power plant on one machine. TPP-3 was a complex of four power self-propelled vehicles.

The first power self-propelled gun carried a nuclear reactor with a transportable biosecurity and a special air radiator for removing residual cooling. The second machine was equipped with steam generators, a volume compensator, and circulation pumps for feeding the primary circuit. The actual power generation was the function of the third self-propelled power plant, where the turbine generator with the equipment of the condensate feed path was located. The fourth car played the role of a control center for the AES, and also had backup power equipment. There were a control panel and a main board with starting means, a starting diesel generator and a battery pack.

Lapidarity and pragmatism played the first violin in the design of power-self-propelled vehicles. Since TPP-3 was supposed to operate mainly in the regions of the Far North, the equipment was placed inside insulated bodies of the so-called carriage type. In cross-section, they were an irregular hexagon, which can be described as a trapezoid placed on a rectangle, which involuntarily evokes an association with a coffin.

The AES was intended to operate only in a stationary mode, it could not work "on the fly". To start the station, it was required to arrange the self-propelled power plants in the right order and connect them with pipelines for the coolant and working fluid, as well as electric cables. And it was for the stationary mode of operation that the biological protection of the PAES was designed.

The biosecurity system consisted of two parts: transportable and stationary. The transported biosecurity was transported together with the reactor. The reactor core was placed in a kind of lead "glass", which was located inside the tank. When TPP-3 was operating, the tank was filled with water. The water layer sharply reduced the neutron activation of the walls of the bioprotection tank, body, frame and other metal parts of the power self-propelled gun. After the end of the campaign (the period of operation of the power plant at one refueling), the water was drained and transportation was carried out with an empty tank.

Stationary biosecurity was understood as a kind of boxes made of earth or concrete, which, before the launch of the floating power plant, had to be erected around self-propelled power plants carrying a reactor and steam generators.

General view of NPP TPP-3

In August 1960, the assembled AES was delivered to Obninsk, to the test site of the Physics and Power Engineering Institute. Less than a year later, on June 7, 1961, the reactor reached criticality, and on October 13, the power plant was launched. Tests continued until 1965, when the reactor worked its first campaign. However, this is where the history of the Soviet mobile nuclear power plant actually ended. The fact is that in parallel the famous Obninsk institute was developing another project in the field of small nuclear energy. It was the floating nuclear power plant "Sever" with a similar reactor. Like TPP-3, the Sever was designed primarily for the needs of power supply for military facilities. And at the beginning of 1967, the USSR Ministry of Defense decided to abandon the floating nuclear power plant. At the same time, work was stopped on the ground mobile power plant: the APS was put into standby mode. In the late 1960s, there was hope that the brainchild of Obninsk scientists would still find practical application. It was assumed that the nuclear power plant could be used in oil production in cases where a large amount of hot water needs to be pumped into the oil-bearing layers in order to raise the fossil raw materials closer to the surface. We considered, for example, the possibility of such use of AES at wells in the area of the city of Grozny. But the station failed even to serve as a boiler for the needs of the Chechen oil workers. The economic operation of TPP-3 was recognized as inexpedient, and in 1969 the power plant was completely mothballed. Forever.

For extreme conditions

Surprisingly enough, the history of Soviet mobile nuclear power plants did not stop with the demise of the Obninsk APS. Another project, which is undoubtedly worth talking about, is a very curious example of a Soviet energy long-term construction. It was started back in the early 1960s, but it brought some tangible result only in the Gorbachev era and was soon "killed" by the radiophobia that sharply intensified after the Chernobyl disaster. We are talking about the Belarusian project "Pamir 630D".

The complex of the mobile NPP "Pamir-630D" was based on four trucks, which were a combination of "trailer-tractor"

In a sense, we can say that TPP-3 and Pamir are connected by family ties. After all, one of the founders of the Belarusian nuclear energy was A. K. Krasin is a former director of IPPE, who was directly involved in the design of the world's first nuclear power plant in Obninsk, Beloyarsk nuclear power plant and TPP-3. In 1960, he was invited to Minsk, where the scientist was soon elected an academician of the Academy of Sciences of the BSSR and appointed director of the atomic energy department of the Energy Institute of the Belarusian Academy of Sciences. In 1965, the department was reorganized into the Institute of Nuclear Energy (now the Joint Institute for Energy and Nuclear Research "Sosny" of the National Academy of Sciences).

During one of his trips to Moscow, Krasin learned about the existence of a state order for the design of a mobile nuclear power plant with a capacity of 500-800 kW. The military showed the greatest interest in this kind of power plant: they needed a compact and autonomous source of electricity for facilities located in remote and harsh regions of the country - where there are no railways or power lines and where it is quite difficult to deliver a large amount of conventional fuel. It could be about powering radar stations or missile launchers.

Taking into account the upcoming use in extreme climatic conditions, special requirements were imposed on the project. The station was supposed to operate at a wide range of temperatures (from –50 to + 35 ° С), as well as at high humidity. The customer demanded that the control of the power plant be as automated as possible. At the same time, the station had to fit into the railway dimensions of the O-2T and into the dimensions of the cargo cabins of airplanes and helicopters with dimensions of 30x4, 4x4, 4 m. The duration of the NPP campaign was determined at no less than 10,000 hours with a continuous operation time of no more than 2,000 hours. The station deployment time was to be no more than six hours, and dismantling had to be done in 30 hours.

Reactor "TPP-3"

In addition, the designers had to figure out how to reduce the consumption of water, which in the conditions of the tundra is not much more accessible than diesel fuel. It was this last requirement, which practically excluded the use of a water reactor, largely determined the fate of the Pamir-630D.

Orange smoke

The general designer and the main ideological inspirer of the project was V. B. Nesterenko, now a corresponding member of the Belarusian National Academy of Sciences. It was he who came up with the idea to use not water or molten sodium in the Pamir reactor, but liquid nitrogen tetroxide (N2O4) - and simultaneously as a coolant and a working fluid, since the reactor was conceived as a single-loop reactor, without a heat exchanger.

Naturally, nitrogen tetraoxide was not chosen by chance, since this compound has very interesting thermodynamic properties, such as high thermal conductivity and heat capacity, as well as a low evaporation temperature. Its transition from a liquid to a gaseous state is accompanied by a chemical dissociation reaction, when a nitrogen tetraoxide molecule breaks down first into two nitrogen dioxide molecules (2NO2), and then into two nitrogen oxide molecules and one oxygen molecule (2NO + O2). With an increase in the number of molecules, the volume of the gas or its pressure increase sharply.

In the reactor, thus, it became possible to implement a closed gas-liquid cycle, which gave the reactor advantages in efficiency and compactness.

In the fall of 1963, Belarusian scientists presented their project of a mobile nuclear power plant for consideration by the scientific and technical council of the State Committee for the Use of Atomic Energy of the USSR. At the same time, similar projects of IPPE, IAE im. Kurchatov and OKBM (Gorky). The preference was given to the Belarusian project, but only ten years later, in 1973, a special design bureau with pilot production was created at the Institute of Nuclear Power Engineering of the Academy of Sciences of the BSSR, which began the design and bench testing of the future reactor units.

One of the most important engineering problems that the creators of the Pamir-630D had to solve was the development of a stable thermodynamic cycle with the participation of a coolant and a working fluid of an unconventional type. For this, we used, for example, the "Vikhr-2" stand, which was actually a turbine generator unit of the future station. In it, nitrogen tetroxide was heated using a VK-1 turbojet aircraft engine with an afterburner.

A separate problem was the high corrosiveness of nitrogen tetroxide, especially in the places of phase transitions - boiling and condensation. If water got into the turbine generator circuit, N2O4, having reacted with it, would immediately give nitric acid with all its known properties. Opponents of the project sometimes said that, they say, the Belarusian nuclear scientists intend to dissolve the reactor core in acid. The problem of the high aggressiveness of nitrogen tetroxide was partially solved by adding 10% of ordinary nitrogen monoxide to the coolant. This solution is called "nitrin".

Nevertheless, the use of nitrogen tetroxide increased the danger of using the entire nuclear reactor, especially if we remember that we are talking about a mobile version of a nuclear power plant. This was confirmed by the death of one of the KB employees. During the experiment, an orange cloud escaped from the ruptured pipeline. A nearby person unintentionally inhaled a poisonous gas, which, having reacted with water in his lungs, turned into nitric acid. It was not possible to save the unfortunate man.

Pamir-630D floating power plant

Why remove wheels?

However, the designers of "Pamir-630D" implemented a number of design solutions in their project, which were designed to increase the safety of the entire system. Firstly, all processes inside the facility, starting from the start-up of the reactor, were controlled and monitored using on-board computers. Two computers worked in parallel, and the third was in a "hot" standby. Secondly, an emergency cooling system of the reactor was implemented due to the passive flow of steam through the reactor from the high-pressure part to the condenser part. The presence of a large amount of liquid coolant in the process loop made it possible, in the event of, for example, a power outage, to effectively remove heat from the reactor. Thirdly, the material of the moderator, which was chosen as zirconium hydride, became an important "safety" element of the design. In the event of an emergency increase in temperature, zirconium hydride decomposes, and the released hydrogen transfers the reactor into a deeply subcritical state. The fission reaction stops.

Years went by with experiments and tests, and those who conceived the Pamir in the early 1960s were able to see their brainchild in metal only in the first half of the 1980s. As in the case of TPP-3, the Belarusian designers needed several vehicles to accommodate their AES on them. The reactor unit was mounted on a MAZ-9994 three-axle semi-trailer with a carrying capacity of 65 tons, for which MAZ-796 acted as a tractor. In addition to the reactor with biosecurity, this block housed an emergency cooling system, a switchgear cabinet for auxiliary needs and two autonomous diesel generators of 16 kW each. The same combination MAZ-767 - MAZ-994 carried a turbine generator unit with power plant equipment.

Additionally, elements of the automated control system of protection and control moved in the bodies of KRAZ vehicles. Another such truck was transporting an auxiliary power unit with two hundred-kilowatt diesel generators. There are five cars in total.

Pamir-630D, like TPP-3, was designed for stationary operation. Upon arrival at the place of deployment, the assembly teams installed the reactor and turbine generator units side by side and connected them with pipelines with sealed joints. Control units and a backup power plant were placed no closer than 150 m from the reactor to ensure the radiation safety of personnel. Wheels were removed from the reactor and turbine generator unit (trailers were installed on jacks) and taken to a safe area. All this, of course, is in the project, because the reality turned out to be different.

Model of the first Belarusian and at the same time the only mobile nuclear power plant in the world "Pamir", which was made in Minsk

The electrical start-up of the first reactor took place on November 24, 1985, and five months later, Chernobyl happened. No, the project was not immediately closed, and in total, the experimental prototype of the AES operated at different load conditions for 2975 hours. However, when, in the wake of radiophobia that gripped the country and the world, it suddenly became known that a nuclear reactor of an experimental design was located 6 km from Minsk, a large-scale scandal occurred. The USSR Council of Ministers immediately created a commission, which was to study the feasibility of further work on the "Pamir-630D". In the same 1986 Gorbachev dismissed the legendary head of Sredmash, 88-year-old E. P. Slavsky, who patronized the projects of mobile nuclear power plants. And there is nothing surprising in the fact that in February 1988, according to the decision of the Council of Ministers of the USSR and the Academy of Sciences of the BSSR, the Pamir-630D project ceased to exist. One of the main motives, as stated in the document, was "insufficient scientific substantiation of the choice of the coolant."

Pamir-630D is a mobile nuclear power plant located on an automobile chassis. It was developed at the Institute of Nuclear Energy of the Academy of Sciences of the BSSR

The reactor and turbine generator units were placed on the chassis of two MAZ-537 truck tractors. The control panel and staff quarters were located on two more vehicles. In total, the station was served by 28 people. The installation was designed to be transported by rail, sea and air - the heaviest component was a reactor vehicle, weighing 60 tons, which did not exceed the carrying capacity of a standard rail car.

In 1986, after the Chernobyl accident, the safety of using these complexes was criticized. For security reasons, both sets of "Pamir" that existed at that time were destroyed.

But what kind of development this topic is getting now.

JSC Atomenergoprom expects to offer the world market an industrial design of a low-power mobile NPP of the order of 2.5 MW.

The Russian "Atomenergoprom" presented in 2009 at the international exhibition "Atomexpo-Belarus" in Minsk a project of a modular transportable nuclear installation of low power, the developer of which is NIKIET im. Dollezhal.

According to the chief designer of the institute, Vladimir Smetannikov, a unit with a capacity of 2, 4-2, 6 MW can operate for 25 years without reloading the fuel. It is assumed that it can be delivered ready-made to the site and launched within two days. It requires no more than 10 people to service. The cost of one block is estimated at about 755 million rubles, but the optimal placement is two blocks each. An industrial design can be created in 5 years, however, about 2.5 billion rubles will be required to carry out R&D

In 2009, the world's first floating nuclear power plant was laid in St. Petersburg. Rosatom has high hopes for this project: if it is successfully implemented, it expects massive foreign orders.

Rosatom plans to actively export floating nuclear power plants. According to the head of the state corporation Sergei Kiriyenko, there are already potential foreign customers, but they want to see how the pilot project will be implemented.

The economic crisis plays into the hands of the builders of mobile nuclear power plants, it only increases the demand for their products, - said Dmitry Konovalov, analyst at Unicredit Securities. “There will be demand precisely because the power of these stations is one of the cheapest. Nuclear power plants are closer to hydropower plants at a price per kilowatt-hour. And therefore, the demand will be in both industrial regions and developing regions. And the possibility of mobility and movement of these stations makes them even more valuable, because the needs for electricity in different regions are also different."

Russia was the first to decide to build floating nuclear power plants, although in other countries this idea was also actively discussed, but they decided to abandon its implementation. Anatoly Makeev, one of the developers of the Iceberg Central Design Bureau, told BFM.ru the following: “At one time there was an idea to use such stations. In my opinion, the American company offered it - it wanted to build 8 floating nuclear power plants, but it all failed because of the "green" ones. There are also questions about economic feasibility. Floating power plants are more expensive than stationary ones, and their capacity is small”.

The assembly of the world's first floating nuclear power plant has begun at the Baltic Shipyard.

The floating power unit, built in St. Petersburg by order of Energoatom Concern OJSC, will become a powerful source of electricity, heat and fresh water for remote regions of the country that are constantly experiencing energy shortages.

The station should be delivered to the customer in 2012. After that, the plant plans to conclude more contracts for the construction of 7 more of the same stations. In addition, foreign customers have already become interested in the floating nuclear power plant project.

The floating nuclear power plant consists of a flat-deck non-self-propelled vessel with two reactor plants. It can be used to generate electricity and heat, as well as to desalinate seawater. It can produce from 100 to 400 thousand tons of fresh water per day.

The life of the plant will be at least 36 years: three cycles of 12 years each, between which it is necessary to refuel the reactor facilities.

According to the project, the construction and operation of such a nuclear power plant is much more profitable than the construction and operation of ground-based nuclear power plants.

Environmental safety of APEC is also inherent in the last stage of its life cycle - decommissioning. The decommissioning concept presupposes the transportation of the station that has expired its service life to the place where it is cut for disposal and disposal, which completely excludes the radiation impact on the water area of the region where the APPP is operated.

By the way: The operation of the floating nuclear power plant will be carried out on a rotational basis with the accommodation of the service personnel at the station. The duration of the shift is four months, after which the shift-crew is changed. The total number of the main operating production personnel of the floating nuclear power plant, including shift and reserve teams, will be about 140 people.

To create living conditions that meet the accepted standards, the station provides a dining room, a swimming pool, a sauna, a gym, a recreation room, a library, a TV, etc. The station has 64 single and 10 double cabins to accommodate personnel. The residential block is as far as possible from the reactor facilities and from the premises of the power plant. The number of attracted permanent non-production personnel of the administrative and economic service, which is not covered by the rotational service method, will be about 20 people.

According to the head of Rosatom Sergei Kiriyenko, if Russia’s nuclear energy is not developed, then in twenty years it may disappear altogether. According to the task set by the President of Russia, by 2030 the share of nuclear energy should increase to 25%. It seems that the floating nuclear power plant is designed to prevent the sad assumptions of the former from coming true and to solve the problems posed by the latter, at least in part.