One of the suggested ways of permanently disposing of spent nuclear fuel and other highly radioactive wastes is to mix them with sand and chemicals and heat the mixture until it turns into glass logs. This is referred to as vitrification. A seventeen-billion dollar vitrification plant is being constructed at Hanford to deal with the toxic soup of radioactive materials and toxic chemicals stored in underground tanks. Elements in the radioactive logs will include palladium, selenium, cesium and zirconium, and other long-lived fission products (LLFP) with a half-life of about one million years.
The Japanese Cabinet Office’s Council for Science, Technology and Innovation works with Japanese corporations through their Paradigm Change through Disruptive Technologies (ImPACT) Program to explore new technologies for Japan’s energy sector. Under this government program a team of researchers from Toshiba Energy Systems & Solutions Corporation have been working on developing a way to recover useful elements from vitrified radioactive waste. Their work involves investigating the reduction of LLFPs into stable and short-lived nuclides. It also involves the recycling of resources from nuclear waste.
The Toshiba researchers in collaboration with the Japan Science and Technology Agency have successfully demonstrated that reusable elements can be extracted from vitrified waste by the use of a molten salt technology. The research team released a joint statement that said that when combined with other technologies developed under the ImPACT program including transmutation from long lived radioactive isotopes to short lived radioactive isotopes, their research might make it possible to reduce the size and or depth of geological nuclear waste repositories.
The researchers successfully recovered dummy LLFP nuclides as solids, molten salts and gases by reducing mock vitrified waste in the molten salt. The silicon monoxide network structures of the silicon dioxides had to be dissolved in the molten salt to permit this extraction. The molten salt is radiation tolerant and can be reused. This results in the reduction of secondary wastes produced by the new process. The team will continue to research practical systems to reuse and minimize high-level radioactive waste.
Making use of such processes presupposes that the vitrified logs of waste are accessible for recycling. Some designs for permanent geological repositories might make this difficult. The Waste Isolation Pilot Plant (WIPP) geological repository for high-level nuclear waste produced by nuclear weapons production near Carlsbad, New Mexico illustrates the problem. The repository has been operating for about fifteen years. It is carved out of an old salt mine. There are big rooms that are filled with waste that are supposed to be permanently sealed when they are full. Originally, huge steel and concrete doors were going to be welded shut.
If there was interest in recycling vitrified waste from the WIPP, the big doors would have to be breached in order to access the vitrified waste. In addition, there have been hydrological studies that indicate that the assumption that the salt mine was safe from migrating ground water is not accurate. If the mine was flooded, crews might face flooded chambers in their attempts to recover the waste. This would greatly increase the cost.
Ultimately, new geological repositories would have to be constructed with recovery and recycling in mind. If the market failed to adopt the recycling technology for any reason, geological repositories constructed on the assumption that the nuclear waste they contain would be recovered might prove to be unsafe if the waste was not ultimately recovered. The Toshiba research is interesting but a lot of factors other than scientific feasibility will govern whether or not it is ever widely implemented.
Blog
-
Radioactive Waste 385 – Toshiba Energy Systems & Solutions Corporation Developing Processes For Recycling Vitrified Waste
-
Nuclear News Roundup Mar 19, 2019
Berks lawmakers react to bill seeking to save nuclear power in Pennsylvania. Readingeagle.com
Dominion Energy said Friday it reached a 10-year deal with Connecticut utilities to keep the state’s only nuclear power plant in service. Kallenishenergy.com
Poet shares experience writing about nuclear devastation. Thecampuscurrent.com
-
Geiger Readings for Mar 19, 2019
Ambient office = 133 nanosieverts per hour
Ambient outside = 112 nanosieverts per hour
Soil exposed to rain water = 115 nanosieverts per hour
Carrot from Central Market = 80 nanosieverts per hour
Tap water = 97 nanosieverts per hour
Filter water = 93 nanosieverts per hour
-
Nuclear Reactors 662 – Nuclear Industry Appealing To Nuclear Regulatory Commission For Relief From Inspections and Reporting
Many years ago, shortly after I left college, I was talking to some folks about nuclear power. I said that I was confident that engineers could design safe systems but that we would have to rely on government and industry to be far more competent and honest than they had ever been in order to use nuclear power without major accidents. After years of writing these essays about nuclear issues, I see no reason to change my opinion.
The nuclear power industry is appealing to the Nuclear Regulatory Commission to cut back on the number of inspections at U.S. nuclear power plants. They also want to be able to tell the public less about problems at their plants. The NRC is currently considering some of the requests by the nuclear industry as they conduct a major review of how the Commission enforces regulations at the ninety-eight operating nuclear power reactors. The five-member board of the NRC will be issuing their recommendation in June.
Annie Caputo is a member of the NRC board appointed by President Trump. Previously, she was a lobbyist for the nuclear industry. At a nuclear industry meeting this week, she said that she was “open to self-assessments” by nuclear power plant operators. Members of the nuclear industry are suggesting that self-reporting by plant operators be allowed instead of some NRC inspections.
The Trump administration is well-known for being hostile to federal regulation of U.S. industries, including the nuclear industry. Trump has appointed four members of the current five-member board. Trump appointees and industry representatives claim that changes in oversight are overdue because the industry has improved its safety record and the nuclear industry is having financial problems turning a profit at some power plants. The cost of operating aging nuclear power plants is rising as the cost of renewables and natural gas is falling.
In reaction to this activity at the NRC, nuclear industry critics are alarmed at the idea of relaxing regulations and trusting the industry to monitor itself. Geoffrey Fettus is a senior attorney for nuclear issues at the Natural Resources Defense Council. He points out that the regulation cutting in some federal departments would not lead to the kind of accidents such cutting may risk at nuclear power plants. Paul Gunter is a member of the anti-nuclear group Beyond Nuclear. He said, “For an industry that is increasingly under financial decline … to take regulatory authority away from the NRC puts us on a collision course with a nuclear accident.”
The nuclear industry made its request for regulatory changes in a letter from the Nuclear Energy Institute. One major request has to do with eliminating required press releases about lower level safety issues at plants. Such problems could result in increased inspections and oversight at a nuclear power plant but would not be considered emergencies. The industry group requested that the NRC relieve the industry of the “burden of radiation-protection and emergency-preparedness inspections.” Industry representatives repeated their requests at an annual industry function in Washington, D.C. this week.
Greg Halnon is the vice president of regulatory affairs for FirstEnergy Corp. in Ohio. He said that it would be better to scale back reporting of lower-level problems at plants “than to put out a headline on the webpage to the world.” He said that following reporting of such lower level problems there were “rapid calls from the press and SEC filings get impacted because of potential financial impact.”
The NRC will be issuing a new set of regulations this spring in response to the lessons learned from the 2011 Fukushima disaster. Nuclear power plants will be required to harden themselves against major floods and other natural disasters that could result the release of radioactive materials.
Over the past seventy years of nuclear power generation there have been many stories of nuclear power plant operators failing to follow regulations requiring safety measures and the reporting of problems. It would be far better for the citizens of this country to have the NRC concentrate on enforcing regulations than removing them. -
Geiger Readings for Mar 18, 2019
Ambient office = 81nanosieverts per hour
Ambient outside = 96 nanosieverts per hour
Soil exposed to rain water = 100 nanosieverts per hour
Bartlett pear from Central Market =126 nanosieverts per hour
Tap water = 122 nanosieverts per hour
Filter water = 106 nanosieverts per hour
-
Geiger Readings for Mar 17, 2019
Ambient office = 119 nanosieverts per hour
Ambient outside = 112 nanosieverts per hour
Soil exposed to rain water = 116 nanosieverts per hour
Jalepeno pepper from Central Market = 80 nanosieverts per hour
Tap water = 71 nanosieverts per hour
Filter water = 63 nanosieverts per hour
-
Geiger Readings for Mar 16, 2019
Ambient office = 112 nanosieverts per hour
Ambient outside = 88 nanosieverts per hour
Soil exposed to rain water = 84 nanosieverts per hour
Yam from Central Market = 90 nanosieverts per hour
Tap water = 90 nanosieverts per hour
Filter water = 85 nanosieverts per hour
Dover sole – Caught in USA = 73 nanosieverts per hour