An efficient method for processing radioactive waste has been proposed in Russia.
The question of what to do with the waste remaining after nuclear tests and working with radioactive materials has been pressing for decades. Toxic burial sites pose potential dangers to the population even when located at considerable depths. Radiochemists from the Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Sciences (GEOKHI RAS) have patented an effective method for processing such waste.
Hazardous Waste
The Russian “Law on the Use of Atomic Energy” of November 21, 1995 (No. 170-FZ) states that radioactive waste (RW) includes nuclear materials and radioactive substances in solid, liquid, or gaseous form that are no longer suitable for use. They can result from the activities of defense plants, enterprises associated with atomic energy, nuclear power plants, ships, and other types of transportation powered by atomic energy, as well as accidents leading to radiation releases.
Even for those without specialized knowledge, it is clear that such emissions and carcinogenic substances pose a threat to the environment and living beings. Therefore, waste with radioactive properties is stored in special repositories, where they are supposed to be securely isolated from the surrounding environment.
Improper disposal of RW leads to soil, water, and air pollution, not to mention the creatures living there. According to the IAEA, millions of tons of hazardous waste have already accumulated in Russia, and storage facilities are replenished with another five million tons annually.
Even ordinary landfills significantly worsen the ecological situation and harm all living things around. If these are radiation waste dumps… There is data suggesting that people near such areas often fall ill, and children are born with anomalies. Sometimes in these zones, “birds do not sing, and trees do not grow,” in the literal sense of the words. Even if the burial site is at a sufficient distance from populated areas, its mere presence sometimes sparks social protests.
In today’s Russia, the Federal State Unitary Enterprise “National Operator for Radioactive Waste Management” (NO RAW) is addressing the issue of waste disposal.
“Previously, our country lacked a national operator responsible for isolating radioactive waste. There was no system to solve this problem. There were not even final disposal facilities,” commented Nikita Medyantsev, Director of the Department of Public Relations and Media at NO RAW. “Changes only occurred after the relevant federal law was adopted in 2011, thanks to which our enterprise was formed in 2012.”
Dry storage facility for spent nuclear fuel (DSSF) at the Zaporozhye NPP in Energodar / Photo by RIA Novosti
Final disposal facilities for RW have appeared in Novouralsk, Sverdlovsk Oblast, Ozersk, Chelyabinsk Oblast, Seversk, Tomsk Oblast, and other Russian cities over these years. However, despite thorough environmental monitoring, the possibility of leaks and contamination still remains.
There are alternative methods for RW disposal. For example, incineration in plasma furnaces, compression, cementing and bituminization, vitrification in borosilicate glass, synroc, encapsulation. As a result, either the volume of waste is significantly reduced, requiring less space for burial, or an isolating layer is created that does not allow radiation to pass through.
Repetitive Cycles
However, this only concerns disposal, and it’s essential not to forget that the process is by no means cheap and quite burdensome for the state budget. Meanwhile, raw materials for nuclear fuel, for example, are in short supply.
What if we initiate a closed-cycle for processing such waste? By the way, in its December report “Nuclear Technology Review – 2023,” the IAEA notes the increasing relevance of creating special methods for handling and processing nuclear fuel. Primarily, this involves working with oxidized uranium and uranium-plutonium fuel.
This is precisely what the scientists at GEOKHI RAS have been working on.
As explained by Boris Myasoedov, the chief scientific researcher of the radiochemical laboratory at the institute, an academician, a doctor of chemical sciences, and the chairman of the Interdepartmental Scientific Council on Radiochemistry at the RAS and Rosatom State Corporation, in an open nuclear cycle, fuel is placed in a reactor, irradiated, and after the cycle is completed, stored in a water environment in special basins or in a dry state.
In a closed cycle, the irradiated uranium is removed from the reactor and processed. In other words, it can be reused for energy generation, which is much more economically advantageous. Scientists from various countries are actively working on this task.
“Theoretically, natural uranium can be processed up to five times, but additional costs and increased protection against radioactive radiation are required,” explains Academician Myasoedov. “However, this solves the problem of the shortage of uranium raw materials. Modern Russian technologies allow processing such fuel about three times. In the future, it may be possible to increase the number of processing cycles to ten. These technologies must meet all radiation safety requirements.”
According to Myasoedov, the complex work on so-called multi-recycling of nuclear materials includes four directions. Two of them are mainly research-oriented. The first direction aims to increase the efficiency of applying the energy potential of nuclear fuel while simultaneously reducing the volumes of radioactive waste. The second is to develop new technologies for processing used nuclear fuel.
The other two directions are related to solving practical problems at enterprises in the nuclear industry. This primarily involves reducing the volumes of liquid and solid radioactive waste, their isolation, and disposal. In addition, there are plans to gradually decommission facilities associated with nuclear and radiation hazards.
A preliminary discussion of the project took place in 2018 at the thematic Scientific and Technical Council No. 5 of the Rosatom State Corporation. In 2019, it received approval from the Russian Federation Science Committee.
Implementation – Already Today!
The working title of the technology developed by specialists from GEOKHI RAS is the “Iron Purex Process.” The development was ordered by the private enterprise “Science and Innovations,” collaborating with Rosatom.
“The essence of the methodology is to extract long-lived isotopes such as americium, curium, and rare earth elements from high-radioactive waste. To do this, we use tributylphosphate, an extractant that has proven itself reliably for several decades,” said Sergey Vinokurov, Deputy Director for Scientific Work at GEOKHI RAS, head of the radiochemistry laboratory, and a doctor of chemical sciences. “If we manage to practically implement our invention, it will be possible to reduce the volumes of the most dangerous waste with a long period of radioactivity by orders of magnitude, as well as the costs of their burial.”
This is how the Purex process is carried out / Photo courtesy of the press service of GEOKHI RAS
As of today, these technological solutions are still undergoing tests conducted under the auspices of Rosatom. According to the developers, it is planned that this technology will be applied at the radiochemical plants of the new generation. However, some methods, such as the use of phosphate materials, may be implemented in the very near future at some enterprises in the relevant industry.
By Irina Shlionskaya