There has been intense debate over the reprocessing and recycling of uranium and plutonium over the last few decades. Russia’s Rosatom has extensive experience in this area and is involved in all elements of the nuclear fuel cycle, and sees it as the best path forward to making nuclear energy sustainable over the long term. David Flin reports on Rosatom’s activities
Several countries have concluded that fast reactors will be an important element of their future nuclear power programmes.
Of the six concepts for innovative nuclear energy systems being developed by the Generation IV International Forum, four are based on fast reactors. Reprocessing and recycling have the potential, compared to the once-through use of uranium, to increase by a factor of 50 the amount of time during which humanity can derive fission energy from uranium resources.
These issues have to be considered when calculating comparative costs of the fuel cycle. It is usual for the cost of recycling to be calculated using the assumption that the price of uranium will remain stable. Calculations often also neglect the higher waste management costs of the once-through cycle, along with the extra environmental harm associated with the greater mining requirements of the once-through cycle. This holistic approach to cost shows that reprocessing is not prohibitively expensive, but is cost-competitive.
Many critics of reprocessing believe that the world’s available uranium resources are plentiful and that closing the fuel cycle is not necessary. This is a short-sighted argument. The quantity of uranium is finite, and fission energy is therefore not renewable. The Red Book of uranium resources, produced by the International Atomic Energy Agency and the Nuclear Energy Agency, indicates that, as of 2013, the world’s available uranium amounted to about 7.6 million tonnes, enough for about 150 years at current rates of consumption. However, consumption is certain to increase as an increasing number of countries turn to nuclear energy.
Management of waste is the aspect of nuclear energy most focused on by the public. The once-through fuel cycle presents two serious problems in this regard. Firstly, because the once-through cycle involves disposing of uranium and plutonium as waste after only one use, a larger volume of waste results. This creates a greater need for repositories and an impractically long time period over which they need to be monitored.
Secondly, a significant number of countries are establishing nuclear power sectors today, but most nations do not have sites geologically appropriate for disposal of irradiated fuel.
Because Rosatom is involved in all aspects of the fuel cycle, it can provide an overview of the whole system. There are a number of challenges that a closed fuel cycle addresses. These include: the need to extend uranium resources, the need for fuel economy, and the need for waste disposal.
These challenges may be addressed by switching to a new technology platform, a closed nuclear fuel cycle powered by fast-neutron reactors. Creating such closed nuclear fuel cycles will make it possible to use accumulated uranium-238 as an energy resource, and enable the use of non-waste technologies in the nuclear power industry. They may increase the energy potential of the natural uranium many times, due the expanded nuclear fuel breeding.
Without these, nuclear and fossil fuel-fired power plants will ultimately face a shortage of usable materials sometime in the next century, many experts claim.
Last year, Russia began to switch over to the closed nuclear fuel cycle with fast-neutron reactors. In November 2016, BN-800 at the Beloyarsk Nuclear Power Plant entered operation, and the Mining and Chemical Combine started producing MOx Fuel.
These two events are the world’s first attempts to build an international breeder. The BN-800 is a prototype of the BN-1200 reactor, which is currently being designed. In addition, the Siberian Chemical Combine is developing the Pilot Demonstration Energy Complex (PDEC) as part of the Proryv (Breakthrough) Project.
PDEC should become the world’s first unit to show a stable operation of the entire complex, consisting of a BREST-300 based power unit, a fuel fabrication/refabrication module, and a fuel recycler, closing the fuel cycle at a single site.
The closed nuclear fuel cycle requires 150 times less natural uranium. It allows companies to either cut back heavily on uranium mining or increase generation at nuclear power plants with the same level of extraction. This has the consequence of increasing the life of the nuclear industry from hundreds to thousands of years.
Importantly, the radiation equivalent approach employed in the closed nuclear fuel cycle makes sure that radiation safety of the environment is achieved by the absence of natural level increases, rather than through prevention through technology. Since nuclear generation does not emit any greenhouse gases, power plants may use U-238 to generate any amount of energy without detrimental effects on the planet’s climate. Russia is a leading player in the adoption of the closed cycle, which will not only ensure fuel base conversion in the nuclear power industry, but will also contribute to non-proliferation of nuclear weapons.
Credit: International Energy Agency
Conversion of weapons-grade material into fuel helps lock away such material. In February 1993, Russia and the US signed the Agreement Concerning the Disposition of Highly-Enriched Uranium Extracted from Nuclear Weapons, known as ‘Megatons to Megawatts’. During the 20-year Megatons to Megawatts Programme, a total of 500 tonnes of Russian HEU was converted into LEU and sold to the US for use as fuel in American nuclear power plants.
In 2013, the intergovernmental project on LEU supply to the US was completed in full, and over this period, separate divisions of Rosatom’s TVEL Fuel Company converted nuclear material for use as fuel in American plants.
Russia made around $17 billion on HEU-to-LEU conversion. The US used proceeds from LEU supplies to fund programmes intended to enhance the safety of Russian nuclear power plants, convert defence enterprises and remedy contaminated and polluted lands. The Megatons to Megawatts Programme allowed US power plants to generate more than 7000 TWh.
There are a number of advantages in using a closed nuclear fuel cycle in fast-neutron reactors powered by blended uranium-plutonium fuel. These include: no more severe accidents; continuous reduction of accumulated spent nuclear fuel; no real restrictions on fuel base for several millennia; technological support for the non-proliferation regime; and a competitive edge against other power technologies.
|The Pilot Demonstration Energy Project (PDEC)|
The task that faces the international community today is to reduce CO2 emissions significantly to deal with growing concerns about climate change and possible average temperature increase on Earth. As a result, non-hydrocarbon energy is ever more in demand.
The nuclear industry is, self-evidently, part of the non-hydrocarbon types of power generation. It has minimal environmental impact and helps to avoid substantial greenhouse gas emissions. With 60 years of operational experience, VVER reactors have save 15,000 megatons of CO2 emissions, equivalent to 40 1-GW coal-fired power stations. It is a tangible contribution to the struggle against climate change.
|Beloyarsk nuclear power plant|
The nuclear power industry employing the closed nuclear fuel cycle as compared to non-nuclear power generation seeks to become a top eco-friendly power generation method for the first time in its history, as it makes it not only unnecessary to burn huge amounts of hydrocarbons and provides stable and relatively cheap power generation, but also gains a virtually unlimited resource base thanks to multiple reuses of uranium.
Nuclear power plant operation is not affected by the use of MOX fuel in thermal reactors, and the MOX fuel is no different to that of fresh fuel.
Today, Rosatom is a global player in the world’s nuclear technology market. Its leadership comes from a number of competitive strengths, one of which is assets and competencies in all the nuclear fuel cycle segments. Rosatom incorporates companies from all stages of the technological chain, such as uranium mining and enrichment, nuclear fuel fabrication, equipment manufacturing and engineering, nuclear power plant operation, and spent fuel and nuclear waste management. Rosatom brings together over 320 organizations and enterprises employing over 250,000 people.
Rosatom’s self-sufficiency in raw materials rests upon domestic uranium mining and joint venture mining elsewhere, including in Kazakhstan, Tanzania, Namibia and the US.
|Callaway nuclear plant in the US|
The corporation is also preparing to develop a major uranium deposit in Tanzania. Rosatom State Atomic Energy Corporation ranks second globally in uranium reserves and fourth in annual uranium extraction. Annually, Russia produces approximately 3000 tonnes of uranium domestically, and around 5000 tonnes in other countries. The uranium is mined by shaft technique and borehole in-situ leaching.
Rosatom covers 17 per cent of the nuclear fuel fabrication market. In 2015-2016, fuel assemblies fabricated by Rosatom were installed into 72 Russian-designed reactors in 11 countries as part of the latest preventative maintenance works at corresponding units. In 2016, Rosatom partnered with Areva to supply fuel and components produced at a Russian plant from reprocessed uranium to three PWR power units in three EU member countries.
Rosatom has developed its own fuel assembly designs for PWR reactors, based on the experience gathered with its many years of experience with the VVER-1000 reactors. The TVS-KVADRAT pilot fuel assemblies have been in test operation in Sweden since 2014. In 2016, Rosatom and Sweden’s Vattenfall Nuclear Fuel signed a contract for the commercial supply of TVS-KVADRAT nuclear fuel for Ringhals. In addition, Rosatom signed its first contract with a US energy company for TVS-KVADRAT test operation in the US.
The successful promotion of TVS-KVADRAT fuel assemblies on foreign markets will allow Rosatom to dramatically increase its fabrication market share. Currently, and for the foreseeable future, the PWR segment is the largest market: 233 of 449 existing reactors are PWR reactors, and 50 of 60 reactors under construction are PWRs.
Rosatom has a 36 per cent market share in global uranium enrichment services. Uranium enrichment and conversion are carried out at four separation and sublimation plants. Uranium enrichment is based on a cutting-edge cost-effective gas centrifuge process. Uranium enrichment services and enriched uranium are supplied to over 30 utilities in 16 countries around the world.
Rosatom is second in the world in terms of both installed nuclear capacity and the number of power units in operation. A total of 34 power units operate in Russia at 10 nuclear power plants.
The combined installed capacity of all Russian nuclear power plants is 27 GW, accounting for 11 per cent of all generating capacity in the Unified Energy System of Russia.
Nuclear power plants generate over 18.3 per cent of Russian electricity.
David Flin is a freelance journalist focusing on the energy sector