China3D printingNet, June 20, in 1989, at a hearing of the Subcommittee on Transportation and Hazardous Materials in the United States, a woman named Millie Smith (Millie Smith) revealed that she was the 20,000 children identified by the Centers for Disease Control of the United States. One of the victims of secret radioactive release material. According to experts, the 50 million gallons of nuclear waste stored in the underground storage tanks of the Hanford Nuclear Production Plant in the Columbia River in Washington State have been stored for decades and today is still one of the worst nuclear disasters in history. The lady’s narrative revealed dozens of cases of life-threatening diseases. There are 450 nuclear reactors in operation in 31 countries around the world. Therefore, the disposal of spent nuclear waste will cause everyone’s attention.
While looking for a solution to the nuclear waste problem, scientists discovered how to recycle nuclear fuel. Waste from nuclear reactors can be recycled in a variety of ways, including a method developed by the U.S. Department of Energy (DOE) Argonne National Laboratory in the 1970s. Until recently, nuclear engineers could still recover 95% of spent nuclear fuel from the reactor, while only 5% could be stored as long-term waste.However, scientists at the Argonne National Laboratory have been looking for ways to reuse nuclear waste. Last year, they used3D printingThe flexibility as a way to recycle up to 97% of the spent fuel produced by nuclear reactors. This new method can greatly reduce the amount of used fuel stored and reduce the time it remains dangerous.
As detailed in an article in Scientific Reports, Argonne scientists have3D printingParts, paving the way for recycling more nuclear waste than ever before. Co-authors Peter Kozak, Andrew Breshears, and Alex Brown report that their model originated from a technology called in-series element lanthanide separation process (ALSEP) discovered in 2013. They claim that in the past, researchers have been trying to find a way to transfer their work from a laboratory scale to a larger industrial field, but this situation has changed significantly due to the incorporation of additive manufacturing.
Argon scientists from left to right: Peter Kozak, Andrew Breshears, M Alex Brown (Source: Argonne National Laboratory)
In order to better understand the process and consequences of this discovery, Kozak, a chemical engineer at Argonne, said that he is interested in the additive manufacturing applications of nuclear engineering. Kozak is a member of the Argonne team of scientists. They redesigned the ALSEP process around a device called a centrifugal contactor (a solvent extraction device used to separate chemical elements, including nuclear fuel reprocessing and medical isotope production). Material manufacturing to replicate, thereby providing flexibility and reliability, and a fast manufacturing process. By printing contactors and linking them together, Argonne’s engineers realized a continuous ALSEP process.
In the past 70 years, solvent extraction has been the main means to separate heavy metals from light metals and each other. Years of development and progress have produced different equipment to complete the process, including mixing settlers and separation towers. Centrifugal contactors can mix, separate and pump solutions using only a single moving part, and therefore represent the most effective equipment for solvent extraction processes from benchtop to large-scale. Kozak said, “Imagine you decide to make a cake. You can beat the eggs with one hand, beat the sugar and mix the batter. Using old technology requires a lot of work. If you can, you might use a stand mixer. By analogy, your old blender and blender are your hand blenders. Our centrifugal contactor is your new, low energy consumption vertical mixer. “
According to China3D printing The net understands that almost every part of the contactor passes through3D printing, In addition to electrical components such as motors and electricity. The contactor housing, rotor and interstage wires are made by acrylic stereolithography assembly (SLA). The structural parts are printed from carbon fiber reinforced polyethylene terephthalate on a silk-based printer. These materials were chosen because of their chemical resistance and mechanical strength.
“The housing and rotor of the contactor are made by stereolithography assembly on the Formlabs Form 2 printer. The structural parts are manufactured by fuse manufacturing on several different machines we own.” Kozak said.
The scientists used the Argonne National Laboratory3D printingResources to make contactors for desktop demonstrations. For Kozak, additive manufacturing methods can simplify the manufacturing process and reduce labor and material costs. In addition, layer-by-layer assembly allows the manufacture of complex fluidic devices with internal channels as individual components. Take advantage of flexibility to integrate multiple contactor stages into a single multi-stage module, thereby reducing the workload required for installation and eliminating potential points of failure.In the process, scientists discovered the use of3D printingTwo other benefits of components. The first is that the contactor provides an inherent safeguard against nuclear proliferation. A tube connecting 20 contactors runs inside each device, which makes it more difficult to transfer material or other radioactive materials from the process. In addition, Kozak believes that ” 3D printingThe parts are flexible, so it is easy to reprint and replace. “This is also today3D printingOne of the big advantages is that if a part fails, it can be easily reprinted and replaced.
Even after five years of operation in the reactor, it is estimated that more than 90% of the fuel’s potential energy is retained. There are even some advanced reactor designs under development that may consume or use spent nuclear fuel in the future, while a 1,000 megawatt electric (MWe) nuclear reactor requires about 27 tons of fresh fuel per year. “As nuclear fuel fission decays and is radiated into the reactor, a part of the fission material is converted into other elements, called fission products. Some of these fission products interfere with the fission reaction, so once about 95% to 97% of the fuel passes through In this process, the piston rod must be replaced. As a result, most nuclear waste is actually usable fuel, as long as it can be separated and reformed into fuel rods. This usable fuel can be processed in several different ways. Initial recovery, but has historically been done using a solvent extraction process called UREX (similar to ALSEP) and can be done using centrifugal contactors (including contactors made by AM).”
Multi-level contactor module used to develop the ALSEP library (Source: Argonne National Laboratory)
If scientists find a way to recover 97% of nuclear waste, what about the remaining 3%? According to Kozak, “The main reason for not recycling 3% is not because of technical challenges, but because of the low radioactivity and short life of these components. The material simply does not have enough value or danger to justify the cost of recycling. And geological storage is an acceptable alternative to these 3%. If part of the remaining 3% is of value to the industry and suppliers, there may be a technical push to extract them. Therefore, this is not a difficult problem, and It’s the value-added problem brought about by continuing the process.”
Although this method is still in the early stages of research, Kozak and his colleagues believe that more work needs to be done, so they plan to continue to explore new methods to reduce the scale of the method and achieve greater separation.Actually,KozakSaid: “Centrifugal contactors will not be used in every nuclear power plant in the United States. In addition, compared with reactors, the Nuclear Regulatory Commission (NRC) has a separate permit and application process for spent fuel sites. Therefore, nuclear power plants and The spent nuclear fuel reprocessing plant will be in a very different place, and the centrifugal contactor will only be used in the future.The United States currently finds itself relying on an open fuel cycle and has not carried out large-scale reprocessing of commercial spent nuclear fuel. Now, the spent fuel assembly is taken out of the reactor and then simply stored on-site in NRC-approved and licensed spent fuel storage barrels scattered throughout the United States. In this case, fuel will only occupy space in multiple locations in the United States. “Kozak said.
Historically, experts believe that nuclear power is a reliable source of energy, with a greenhouse gas footprint comparable to wind and solar energy, and because the demand for electricity is growing at twice the rate of overall energy use, the world needs to increase energy supply . However, the obstacle to its expanded use is the management and disposal of the radioactive by-products of nuclear fission. Although nuclear energy only accounts for about 10% of the world’s electricity, the waste generated is still a concern of the government and the whole society. The suggestions made by Argonne scientists bring them closer to reusing nearly 100% of spent fuel and will help overcome the development towards a more sustainable and environmentally friendly direction.
China3D printing Net compile article!
(Editor in charge: admin)
0 Comments for “Argonne scientists discuss the use of 3D printing to recycle nuclear fuel”