Center of Applied Research
(Former Nuclear Centre)
Short history of nuclear reactor
In the spring of 1957, by the initiation of academician Elephter Andronikashvili, the director of the Institute of Physics, the construction of the research nuclear reactor IRT-2000 started in the village of
Mukhatgverdi, not far from Tbilisi, and on November 21, 1959 it was officially opened. During many years the reactor has been reconstructed several times, as a result of which the reactor
power was increased from 2 megawatt to 8 megawatt. The nominal power was 5 Mw. The enrichment of the used nuclear fuel was changed from 10% to 90% after using U-235 isotope and the
reactor was renamed as IRT-M.
During the exploitation process of the reactor, the accumulated used nuclear fuel was carried out step-by step to the Russian Soviet Federation Socialist Republic beginning from 1984. The last
carrying out (in the period of the Soviet Union) was made in 1988.
On December 29, 1987 the exploitation of the reactor was ceased for implementation of the planned repair –and- prophylactic work and it was not renewed any more.
In 1990, due to the negative attitude of a certain part of Georgian public to the functioning of nuclear reactor, the Presidium of the Georgian Academy of Sciences adopted the resolution to take the
necessary measures to decommission and shutdown the scientific research reactor located on the territory of Nuclear Centre. According to the decision, the nuclear fuel was removed from the reactor
core and the exploitation of the reactor was ceased.
According to the agreement about the nonproliferation of nuclear weapons, in 1998, both the used and unused nuclear fuel remained in the reactor was fully transported from Georgia.
In 2000 under the aegis of International Atomic Energy Agency (IAEA) the implementation of the program about decommissioning of the reactor was started. On the first stage of the program the
work on concreting the lower part of the radioactively contaminated reactor pool and the radioactive waste obtained as a result of reactor exploitation was carried out.
During the following years again under the aegis of IAEA, some projects were fulfilled within which the dismantling of radioactively contaminated peripheral technological nodes and the provision of
their safe storage were carried out. The last project was implemented in 2016.
By using the nuclear reactor, the scientists of the institute of physics perform the scientific research work in such spheres, as nuclear reactor physics, applied nuclear physics, neutron physics, solid-state
radiation physics, low-temperature radiation physics of materials, low-temperature radiation physics and radiation chemistry and biophysics.
During the whole period of operation of the reactor there was no emergency situation that could have a negative influence on the human health or could cause the contamination of the environment.
Some facilities and technologies developed at the Nuclear Centre
(during the period of reactor operation)
The increase of the power of IRT-M reactor up to 5000 kW was carried out both in core and heat-exchangers of cooling system at the expense of significant intensification of the process of
convectional heat exchange. Such effect was obtained on the surfaces of the rods of nuclear fuel (heat transfer elements) and of the channels of heat exchangers by means of creation of the so-called two-
dimensional artificial roughness. As a result, at the expense of the increase of cooling water turbulence, the coefficient of heat transfer was significantly increased and hence, it became possible
to increase the nominal power of the reactor.
At the Nuclear Centre the equipment for checking the hermeticy of reactor fuel was created allowing the checking of hermeticity of nuclear fuel (heat transfer assembly) for a minimum period of time
and with a maximum efficiency. The equipment was placed in the reactor pool and the heat transfer assemblies containing nuclear fuel were inserted in turn. The equipment was shut and by measuring
the activity of gaseous radionuclides coming out from special channels of the equipment and formed as a result of radionuclide fission, the degree of hermeticity of the assembly was determined.
In many scientific experiments the gamma-radiation was used the intensity of which in reactor core is rather high. But in the reactor beside the gamma-radiation there are also the radiations of other
types that make difficult the fulfillment of certain researches. Due to this fact, the so-called In-Ga radiation loop was created at the Nuclear Centre. Next to the core the so-called generator of activity
was located, in which In-Ga alloy was activated as a result of neutron absorption. Then, the radioactive In-Ga was pumped into the so-called irradiator located outside the reactor and thus the
"pure" gamma-radiation was obtained. One of the significant results of using this equipment was the obtaining of the so-called modified wood material, when the soft wood material (i.e. fir) was
transformed into hard wood material. This technology was based first on soaking the wood material by dichloroetane and then its treatment by gamma-rays. The floor of the hall of the Ministry of
Wood Industry was laid just with the parquet made of the modified fir obtained by using this technology.
Among the researches carried out at the institute of physics, one of the priorities was the research devoted to the solid-state radiation physics and low-temperature radiation material science. For
carrying out such experiments the low-temperature experimental channels (vertical and horizontal), the so-called low-temperature loops were created at the Nuclear Centre. By using these experimental
channels it was possible to carry out experiments both at 80 K (by means of cooling by hydrogen) and at 8-10 K (by means of cooling by helium) and besides under the conditions of high irradiation. Since
1973 until the collapse of the Soviet Union, the Institute of Physics was recognized as the leading institution of low-temperature radiation material science.
Decommissioning of the Nuclear Reactor
In 1990s of the previous century, after the Presidium of the Georgian Academy of Sciences adopted the resolution to take the necessary measures to decommission and shutdown, the scientific research
reactor located on the territory of Nuclear Centre, the development of the strategy of decommissioning has started. Finally it was decided to decommission the nuclear reactor by means of
concreting the lower radiation contaminated part of the pool, and in the other "pure" lower part – to create a new low-power reactor.
In regard with this problem and by invitation on behalf of the president of Georgia, Mr. Eduard Shevardnadze, Mr. Hans Blicks, the head of IAEA visited the Institute of Physics on July 16, 1997.
He appreciated the plan of decommissioning developed at the Institute of Physics.
Under the aegis of IAEA the work on concreting the radioactive waste produced in radioactive lower part of reactor pool as a result of reactor operation was started in 2000.
In the following years, again under the aegis of IAEA several projects were developed for dismantling of peripheral radioactive technological loops of the reactor and for their safe storage. In this regard,
the last project was fulfilled in 2016.
Subcritical multiplier
In addition to the nuclear reactor, at the institute of physics there was also one nuclear equipment – subcritical multiplier "Razmnozhitel 1" the power of which was 0.9 W, and the uranium fuel
enrichment was 36%. On this equipment many experimental research and work were fulfilled by using the method of neutron activation analysis, among them - the express analysis of copper mined
in Kazreti. In 2015 under the aegis of DOE USA and PNNL national laboratory, the nuclear fuel of subcritical multiplier was carried out beyond the territory of Georgia.
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Principal Researcher:
Senior Researchers:
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