Ambient office = 93 nanosieverts per hour

Ambient outside = 108 nanosieverts per hour

Soil exposed to rain water = 102 nanosieverts per hour

Blueberry from Central Market = 73 nanosieverts per hour

Tap water = 108 nanosieverts per hour

Filter water = 95 nanosieverts per hour

Dover Sole from Central = 110 nanosieverts per hour

     Rosatom’s Mining and Chemical Combine just produced its first three fuel assemblies with uranium-plutonium mixed oxide fuel (MOX) containing transuranic elements americium-241 and neptunium-237.
     The fuel has been accepted and is due to be loaded into the BN-800 fast neutron reactor at Beloyarsk nuclear power plant in 2024. Pilot operations will consist of three micro campaigns of about one and a half years each.
     Minor actinides are transuranic elements other than plutonium. They are formed in irradiated nuclear fuel. They are highly radioactive with long half-lives.
     Rosatom said that the proposed Russian solution to what are the most hazardous components of nuclear waste is via fast neutron reactors. They can be fueled not only with enriched natural uranium, but also by secondary products of the nuclear fuel cycle, such as depleted uranium and plutonium. Rosatom said, “In addition, the research shows that minor actinides from spent nuclear fuel under the flux of fast neutrons will fission into fragments representing a fairly wide range of radioactive and stable isotopes, but in general their potential hazard will be much lower than that of the original minor actinides.”
     Alexander Ugryumov is the senior vice president for research and development at Rosatom’s fuel division, TVEL. He said, “Rosatom is step-by-step taking the unique advantages that powerful fast neutron reactors provide to our industry. The introduction of MOX fuel enables the expansion of the resource base for nuclear power multifold involving depleted uranium and plutonium, and also to reprocess irradiated fuel instead of storing it. Afterburning of minor actinides is the next step in closing nuclear fuel cycle, which should not only reduce the amount of nuclear waste for final isolation, but also significantly reduce its radioactivity. In the long term, it could avoid the complicated and expensive deep burial of waste.”
     These lead-test assemblies were manufactured at the Mining and Chemical Combine in Zheleznogorsk in the Krasnoyarsk region. Their creation was based on fuel fabrication technology developed at TVEL’s Bochvar Institute in Moscow.
     TVEL said that the pilot operation in the BN-800 reactor “is the key stage of the comprehensive research program” for minor actinides afterburning. The project began in 2021 and is scheduled to run until 2025. TVEL added that “The program includes projects of minor actinides separation into different fractions, their intermediate storage, involvement in fast reactor fuel, operation of such fuel, post-irradiation studies, etc. Another important issue is optimization of reactor facilities for burning the maximum volume of minor actinides.”
     Beloyarsk 4 is a BN-800 reactor cooled by sodium which produces about eight hundred and fifty megawatts. It was brought to minimum controlled power for the first time in June of 2014. It was connected to the grid in December of 2015. The eight hundred and fifty megawatts reactor entered commercial operation in October of 2016. It was fully loaded with MOX fuel in September of 2022. It recently became the first such facility to complete a year operating on MOX fuel. MOX fuel is created from plutonium recovered from spent nuclear fuel mixed with depleted uranium which is a by-product of uranium enrichment.

Ambient office = 95 nanosieverts per hour

Ambient outside = 114 nanosieverts per hour

Soil exposed to rain water = 115 nanosieverts per hour

Bannana from Central Market = 115 nanosieverts per hour

Tap water = 84 nanosieverts per hour

Filter water = 69 nanosieverts per hour

Part 2 of 2 Parts (Please read Part 1 first)
     At MIT, Naranjo De Candido is working on improving access to nuclear energy by scaling down reactor size and making microreactors mobile enough to travel to places where they are needed. She said, “The idea with a microreactor is that when the fuel is exhausted, you replace the entire microreactor onsite with a freshly fueled unit and take the old one back to a central facility where it’s going to be refueled.” One of the early use cases for such microreactors has been to supply power to remote mining sites that require it twenty-four hours a day.
     Modular reactors generate less than three hundred megawatts. The components can be manufactured and installed at scale. These reactors generate industrial heat as well as electricity. Naranjo De Candido said, “You can locate them close to industrial facilities and use the heat directly to power ammonia or hydrogen production or water desalinization for example.”  
     As more of these modular reactors are installed, the nuclear industry is expected to expand to include enterprises that choose to build them and then hand off installation and operations to other companies. Traditional nuclear power reactors usually have a full staff on site. But SMRs cannot afford to staff in big numbers so talent needs to be optimized and staff shared among many reactors. Naranjo De Candido said, “Many of these companies are very interested in knowing exactly how many people and how much money to allocate, and how to organize resources to serve more than one reactor at the same time,”
     Naranjo De Candido is working on complex software that factors in a large range of variables including raw material costs and worker training, reactor size, megawatt output and more. It leans on historical data to predict what resources newer plants might need. The program also alerts operators about tradeoffs they might need to accept. She said, “if you reduce people below the typical level assigned, how does that impact the reliability of the plant, that is, the number of hours that it is able to operate without malfunctions and failures?”
     Managing and operating a nuclear reactor is particularly complex because safety standards limit how much time workers can work in radioactive areas and how safe zones need to be handled.
     Naranjo De Candido said, “There’s a shortage of [qualified talent] in the industry so this is not just about reducing costs but also about making it possible to have plants out there.” Different types of talent are required, from professionals who specialized in electronic controls to mechanical components. Her model considers the need for such specialized skillsets as well as making room for cross-training talent in multiple fields as needed.
     Naranjo De Candido’s optimization software will be open-source, available for all to use. She said, “We want this to be a common ground for utilities and vendors and other players to be able to communicate better.” This will accelerate the operation of nuclear energy plants at scale.

Ambient office = 84 nanosieverts per hour

Ambient outside = 153 nanosieverts per hour

Soil exposed to rain water = 157 nanosieverts per hour

Bannana from Central Market = 110 nanosieverts per hour

Tap water = 151 nanosieverts per hour

Filter water = 143 nanosieverts per hour

Part 1 of 2 Parts
     Many in the energy industry believe that for the U.S. to reach its net zero goals, nuclear energy needs to be one of the options. One of the major problems with nuclear energy is that its production still suffers from a lack of scalability. Isabel Naranjo is a third-year doctoral student at MIT, advised by Professor Koroush Shirvan. She says that to increase access to nuclear energy, we need to build nuclear reactors more rapidly.
     One option is to work with microreactors. These are transportable units that can be sent to areas that need clean electricity. Naranjo De Candido’s master’s thesis at MIT was supervised by Professor Jacopo Buongiorno and it focused on such reactors.
     Another way to improve access to nuclear power is to design and develop reactors that are modular. The components for such reactors can be manufactured quickly while still maintaining quality. Naranjo De Candido said, “The idea is that you apply the industrialization techniques of manufacturing, so companies produce more [nuclear] vessels, with a more predictable supply chain.” The assumption is that working with standardized designs allows the manufacture of just a few components over and over again to improve speed and reliability as well as lowering costs.
     Naranjo De Candido enrolled in a science-based high school shortly after middle school because she knew that that was the track that she enjoyed the most. She was unsure of what field of study she wanted to pursue after she graduated from high school in Padua, Italy.
     Because of her excellent grades in middle and high school, Naranjo De Candido won a full scholarship to study at the special Sant’Anna School of Advanced Studies in Pisa, Italy. The school only grants masters and doctoral degrees. She said, “I had to select what to study but I was unsure. I knew I was interested in engineering so I selected mechanical engineering because it’s more generic.”
     An inspirational nuclear engineering course during her studies inspired her to study nuclear engineering as part of her master’s studies in Pisa. During her time in Pisa, she traveled around the world. She went to China as part of a student exchange program. She also visited Switzerland and the U.S. for internships. She said, “I formed a good background and curriculum and that allowed me to [gain admission] to MIT.”
      During an internship at NASA’s Jet Propulsion Laboratory, Naranjo De Candido met an MIT mechanical engineering student who encouraged her to apply to the school for doctoral studies. Another mentor in the Italian nuclear sector had also suggested that she apply to MIT to pursue nuclear engineering.
    As part of her doctoral studies, Naranjo De Candido is investigating optimization of the operations and management of these small modular reactors (SMRs) so they can be efficient at all stages of their lifecycle including design, construction, operations, maintenance and decommissioning, The motivation for her research is simple. She said, “We need nuclear for climate change because we need a reliable and stable source of energy to fight climate change.”
Please read Part 2 next