The nuclear industry is focusing on new reactor designs to solve various problems, such as climate change, support for renewable energy, and replacement of fossil fuels with reliable baseload alternatives.
This is great and will definitely be part of any long-term solution. However, it will take some time for the new reactors to become popular enough to have a real impact. This is especially true in emerging countries. Energy poverty must be resolved as soon as possible to eliminate global poverty and its evil stepson, war and terrorism. Among all human activities, poverty may have the most serious impact on the environment.
But existing reactors can run faster using new advanced nuclear fuel.
is developing a variety of new nuclear fuels to cope with existing and new generation reactors, including accident tolerance, more durable, cheaper, providing more electricity, providing some old fuel recycling, easier refueling, easier storage and disposal and Anti-proliferation.
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An example of advanced fuel innovation is the Clean Core Thorium Energy (CCTE) fuel, which can solve several of these problems at the same time. Its fuel is called advanced nuclear power or ANEEL for enriching life, and it combines thorium (Th) and HALEU (high-content low-enriched uranium) to solve the problems of cost, proliferation and waste. This fuel does not involve post-processing. The thorium
content is approximately three times that of uranium on land and can be easily extracted from seawater.
This is a CANDU / PHWR nuclear fuel bundle, which looks the same as CCTE’s new ANEEL fuel ... [+] DREAMSTIME
has only 0.7% uranium 235 (U235) in natural uranium and it is easy to divide. The rest is U238, it is not. In most nuclear reactors, it must be concentrated to about 5% U235 to maintain a continuous chain reaction. Except CANDU (Canada Deuterium Uranium)/PHWR (Pressurized Heavy Water Reactor) reactors, which use natural uranium and heavy water (deuterium D2O is hydrogen and its core is neutron).
However, it has long been known that higher levels of U235 enrichment will provide more fuel energy per unit mass, extend reactor core life, allow smaller plant sizes, and increase waste combustion rates.
The current light water reactor (LWR) fleet in the world uses fuel enriched to about 5% U235. But many advanced reactor concepts require HALEU, which has a higher degree of enrichment, between 5% and 20%. CANDU / PHWR reactors in particular can benefit from HALEU.
Concentrations of more than 20% are considered highly concentrated and cannot be accepted by international civil applications.
The ANEEL fuel mentioned above is a proprietary combination of Th and HALEU. U238 is much less than ordinary fuel and 20% less than the 94% used by LWR. Most of the fuel is a Th matrix driven by U235 as a fission driver, providing enough neutrons for continuous fission.
Th232 captures a neutron and converts it to U233, which is also fissile and begins to provide more neutrons and more energy. At the same time, U238 captured a neutron and turned it into Pu239, which also fissioned, almost as fast as it was created.
CANDU reactor core
CANDU reactor core surface, there are hundreds of pressure tubes that can be refueled… [+] MENELEY AND RUAN, Energy Education
As all these fission proceed, ANEEL fuel burns The rate is high, which provides more energy from the same amount of fuel in the reactor. In fact, the combustion rate of ANEEL exceeds 50 GWd/t, which far exceeds the current CANDU/PHWR natural uranium fuel rate of 7 GWd/t, which means that the reactor only needs about one-seventh of the fuel during its operation. Useful life. , Which translates into significant savings and benefits in operating costs, fuel and waste management.
In addition, thorium and the resulting higher combustion lead to increased resistance to proliferation caused by deep plutonium combustion throughout its life cycle. This will increase the amount of Pu240 and Pu242 regenerated in the fuel, which are neutron poisons for the uncontrolled chain reaction required by nuclear weapons.
CANDU / PHWR usually use natural uranium oxide (0.7% U235) as fuel, so they need more efficient moderators (materials that slow down or slow down the speed of neutrons so that it hits the next nucleus at the correct speed to split, or Fission, that). In this case, these reactors use heavy water (D2O).
is different from LWR. Because of its design, the CANDU/PHWR reactor does not have to be shut down for refueling and can be refueled at full power. After the initial operation of today’s smaller CANDU/PHWR reactor (200 300 MWe) for 150 days, 8 bundles of natural uranium weighing approximately 15 kg must be replaced every day for the remaining 60-year life of the reactor.
However, for the ANEEL fuel bundle weighing approximately 10.65 kg, after 1,100 days of initial operation, only one fuel bundle will be replaced on average during the remaining 60-year life of the reactor, resulting in waste and the described benefits.
Similarly, a 600 MWe CANDU / PHWR powered by 37 PIN natural uranium requires 348,000 fuel bundles in 60 years. Using the same ANEEL 37 PIN, 600 MWe CANDU / PHWR fuel bundle only needs 61,500 ANEEL fuel bundles in the same 60 years. This will translate into savings of approximately US $ 2 billion in fuel costs, direct disposal of spent fuel, and operating costs over the 60-year life of the reactor.
Therefore, there is an opportunity to realize these benefits through the deployment of ANEEL fuel at CANDU / PHWR planned for worldwide refurbishment, where the life of the reactor will be increased by another 30 to 40 years. This is combined with the higher fuel consumption rate of ANEEL fuel.

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