Radioactivity Neutralization Methods
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Patience Pays Off with Methanol for Uranium Bioremediation Summary:
Uranium contamination is a devastating legacy of nuclear weapon and energy development, but new testing has shown that adding organic molecules can positively affect the bioremediation of uranium, converting it to a solid mineral and sequestering it within the sediment.
The legacy of nuclear weapons and nuclear energy development has left ground water and sediment at dozens of sites across the United States and many more around the world contaminated with uranium. The uranium is transported through ground water as uranyl (U6+). In one bioremediation strategy, uranium immobilization in contaminated ground water and sediment may be achieved by the addition of organic molecules known as electron donors to stimulate microbial activity. The microbial community utilizes the electron donors as ‘food’, consuming all of the available oxygen during aerobic respiration. Once the ground water becomes anaerobic, U6+ may be converted to U4+ as UO2, a solid mineral, sequestering the uranium within the sediment. Researchers have been investigating the effectiveness of various electron donors, but have been frustrated by residual U6+ which is not converted to insoluble U4+. A team of scientists from Oak Ridge National Laboratory has investigated effectiveness of several electron donors for uranium bioremediation in a study funded by the Department of Energy’s Environmental Remediation Sciences Program. Madden et al. report that the particular electron donor chosen affects not only the rate of uranium removal from solution, but also the extent of U6+ conversion to U4+. Results of the study were published in the January-February issue of the Journal of Environmental Quality. Microcosm experiments containing uranium-contaminated sediment and ground water demonstrated equivalent rapid uranium reduction when amended with ethanol or glucose. In contrast, reduction was delayed by several days when microcosms were amended with methanol. Spectroscopic analyses of uranium oxidation state in stimulated microcosm sediment slurries demonstrated almost complete uranium reduction when methanol was the donor, as compared with less than half reduced using ethanol or glucose. However, addition of methanol did not always result in uranium reduction. These results suggest that the use of donors such as methanol which are not as readily and rapidly coupled to microbial metal reduction may lead to increased stability of the subsurface towards uranium immobilization. Research is ongoing at Oak Ridge National Laboratory to investigate the effectiveness of various electron donors for long-term uranium immobilization. Further research is needed to understand the coupling between the microbial community and the biogeochemical processes that occur to immobilize the uranium. While previous research has focused on individual groups of bacteria which most efficiently reduce uranium, these results suggest the need for understanding the microbial community system. Story Source: The above story is based on materials provided by Crop Science Society of America. Note: Materials may be edited for content and length. Journal Reference: 1. Madden et al. Donor-dependent Extent of Uranium Reduction for Bioremediation of Contaminated Sediment Microcosms. Journal of Environmental Quality, 2009; 38 (1): 53 DOI: 10.2134/jeq2008.0071
Crop Science Society of America. "Patience Pays Off With Methanol For Uranium Bioremediation." ScienceDaily. ScienceDaily, 24 February 2009. www.sciencedaily.com/releases/2009/02/090223121411.htm Source: http://www.sciencedaily.com/releases/2009/02/090223121411.htm GE Hitachi Plans to Turn Nuclear Waste into Fuel by Ariel Schwartz, 02/18/10 President Obama’s recent announcement that the U.S. government will offer $8 billion in federal loan guarantees for the first new nuclear plant in the country in 30 years upset clean energy advocates for a number of reasons. One of the biggest problems: All that radioactive waste. Now GE Hitachi Nuclear Energy, one of the world’s biggest suppliers of nuclear reactors, claims that it can safely turn nuclear waste into fuel. Goodbye, Yucca Mountain.
GE’s process separates nuclear waste into three streams: Waste material that needs to be stored underground for a few hundred years (vs. thousands of years for standard nuclear waste), uranium that can be used in deuterium uranium reactors, and a mixture of transuranic elements (plutonium and neptunium) that can be used as fuel in nuclear reactors that use molten sodium as a coolant. In the past, the idea of repurposing nuclear waste into fuel has been criticized because of the potential for terrorists to steal the pure plutonium produced as part of the process and use it for nuclear weapons. But GE Hitachi’s fuel is difficult to steal because the plutonium isn’t separated from other elements, making it difficult to detect. The fuel is far from perfect – deuterium uranium reactors are only found in Canada and molten sodium-cooled reactors haven’t yet been approved in the U.S. – but if the Obama administration is serious about bringing even more nuclear power plants into the world, it might want to look into GE Hitachi‘s process. Source: http://inhabitat.com/ge-hitachi-plan-to-turn-nuclear-waste-into-fuel/ China Finds Way to Extend Life of Nuclear Fuel 60 Times by Brit Liggett, 01/04/11 The Chinese government just announced they’ve made a breakthrough in nuclear fuel reprocessing technology that would increase the reuse rates of nuclear fuel by 60 fold. Though nuclear power remains a touchy subject in the United States, countries around the world – like France, the UK and Russia – are turning to it as a ready-for-the-market technology that can wean them off coal-fired power plants in order to reduce emissions. Reprocessing, disposal and mining are at the top of the list of nuclear energy concerns, but if China’s new breakthrough proves fruitful it could help to diminish the problems that arise with all three.
At present 70% of China’s energy comes from coal-fired plants – that’s a lot of energy driven pollution – and they are making strides to change that number. The country currently has about 10 gigawatts of nuclear energy generation capacity and hopes to increase that to 40 gigawatts by 2020. However, at that increase rate – and with current technology – China’s supply of uranium would only last them 50-60 years. As Chinese Central Television noted, “With the new technology, China’s existing detected uranium resources can be used for 3,000 years.” This new development has Chinese authorities bringing their 2020 nuclear energy generation mark up to 80 gigawatts. Costs, technology and the threat of nuclear weapons proliferation have impeded the use of nuclear fuel reprocessing in the past. Though the Chinese government is holding close the secrets of how exactly this new technological breakthrough works, it would definitely solve the second problem on that list. They’ve announced nothing about the cost of the technology. But if it truly extends their uranium resources 3,000 years, it would possibly have a payoff down the line – however expensive it might be now. Opponents of nuclear power state that uranium mining is extremely destructive, and while this technology could greatly reduce it, it doesn’t solve a lot of their other concerns. We’ll have to hold tight until we see the scientific merits of this new reprocessing technique before we jump on board. Nuclear power is historically an extremely touchy process and adding a complex element to its production could open a whole new door to nuclear power plant disasters. Source: http://inhabitat.com/china-finds-way-to-reuse-nuclear-fuel-60-times-longer/ Nuclear Fusion-Fission Hybrid Could Contribute to Carbon-Free Energy Future Jan 27, 2009 Physicists at The University of Texas at Austin have designed a new system that, when fully developed, would use fusion to eliminate most of the transuranic waste produced by nuclear power plants. The invention could help combat global warming by making nuclear power cleaner and thus a more viable replacement of carbon-heavy energy sources, such as coal. "We have created a way to use fusion to relatively inexpensively destroy the waste from nuclear fission," says Mike Kotschenreuther, senior research scientist with the Institute for Fusion Studies (IFS) and Department of Physics. "Our waste destruction system, we believe, will allow nuclear power – a low- carbon source of energy – to take its place in helping us combat global warming." Toxic nuclear waste is stored at sites around the U.S. Debate surrounds the construction of a large-scale geological storage site at Yucca Mountain in Nevada, which many maintain is costly and dangerous. The storage capacity of Yucca Mountain, which is not expected to open until 2020, is set at 77,000 tons. The amount of nuclear waste generated by the U.S. will exceed this amount by 2010. The physicists' new invention could drastically decrease the need for any additional or expanded geological repositories. "Most people cite nuclear waste as the main reason they oppose nuclear fission as a source of power," says Swadesh Mahajan, senior research scientist. The scientists propose destroying the waste using a fusion-fission hybrid reactor, the centerpiece of which is a high-power Compact Fusion Neutron Source (CFNS) made possible by a crucial invention. The CFNS would provide abundant neutrons through fusion to a surrounding fission blanket that uses transuranic waste as nuclear fuel. The fusion-produced neutrons augment the fission reaction, imparting efficiency and stability to the waste incineration process. Kotschenreuther, Mahajan and Prashant Valanju, of the IFS, and Erich Schneider of the Department of Mechanical Engineering, report their new system for nuclear waste destruction in the journal Fusion Engineering and Design. There are more than 100 fission reactors, called ‘light water reactors’ (LWRs), producing power in the United States. The nuclear waste from these reactors is stored and not reprocessed. (Some other countries, such as France and Japan, do reprocess the waste.)
First, 75 percent of the original reactor waste is destroyed in standard, relatively inexpensive LWRs. This step produces energy, but it does not destroy highly radiotoxic, transuranic, long-lived waste, what the scientists call ‘sludge’. In the second step, the sludge would be destroyed in a CFNS-based fusion-fission hybrid. The hybrid's potential lies in its ability to burn this hazardous sludge, which cannot be stably burnt in conventional systems. "To burn this really hard to burn sludge, you really need to hit it with a sledgehammer, and that's what we have invented here," says Kotschenreuther. One hybrid would be needed to destroy the waste produced by 10 to 15 LWRs. The process would ultimately reduce the transuranic waste from the original fission reactors by up to 99 percent. Burning that waste also produces energy. The CFNS is designed to be no larger than a small room, and much fewer of the devices would be needed compared to other schemes that are being investigated for similar processes. In combination with the substantial decrease in the need for geological storage, the CFNS-enabled waste-destruction system would be much cheaper and faster than other routes, say the scientists. The CFNS is based on a tokamak, which is a machine with a ‘magnetic bottle’ that is highly successful in confining high temperature (more than 100 million degrees Celsius) fusion plasmas for sufficiently long times. The crucial invention that would pave the way for a CFNS is called the Super X Divertor. The Super X Divertor is designed to handle the enormous heat and particle fluxes peculiar to compact devices; it would enable the CFNS to safely produce large amounts of neutrons without destroying the system. "The intense heat generated in a nuclear fusion device can literally destroy the walls of the machine," says research scientist Valanju, "and that is the thing that has been holding back a highly compact source of nuclear fusion." Valanju says a fusion-fission hybrid reactor has been an idea in the physics community for a long time. "It's always been known that fusion is good at producing neutrons and fission is good at making energy," he says. "Now, we have shown that we can get fusion to produce a lot of neutrons in a small space." Producing an abundant and clean source of ‘pure fusion energy’ continues to be a goal for fusion researchers. But the physicists say that harnessing the other product of fusion – neutrons – can be achieved in the near term. In moving their hybrid from concept into production, the scientists hope to make nuclear energy a more viable alternative to coal and oil while waiting for renewables like solar and pure fusion to ramp up. "The hybrid we designed should be viewed as a bridge technology," says Mahajan. "Through the hybrid, we can bring fusion via neutrons to the service of the energy sector today. We can hopefully make a major contribution to the carbon-free mix dictated by the 2050 time scale set by global warming scientists." The scientists say their Super X Divertor invention has already gained acceptance in the fusion community. Several groups are considering implemented the Super X Divertor on their machines, including the MAST tokamak in the United Kingdom, and the DIIID (General Atomics) and NSTX (Princeton University) in the U.S. Next steps will include performing extended simulations, transforming the concept into an engineering project, and seeking funding for building a prototype. The illustration in http://cdn.physorg.com/newman/gfx/news/hires/2009/nuclearfusio.jpg shows how a compact fusion-fission hybrid would fit into a nuclear fuel cycle. The fusion-fission hybrid can use fusion reactions to burn nuclear waste as fuel (people are shown for scale). It would produce energy and could be used to help destroy the most toxic, long-lived waste from nuclear power. The hybrid would be made possible by a crucial invention from physicists at the University of Texas at Austin called the Super X Divertor. Credit: Angela Wong Source: http://phys.org/news152284917.html#jCp Accelerator-Driven Transmutation of Nuclear Waste Advanced Accelerator Applications and Transmutation of Nuclear Waste March 13, 2002 Denis E. Beller, Ph.D. Los Alamos National Laboratory and University of Nevada, Las Vegas Abstract: In 1999 the U.S. Department of Energy developed a roadmap for research, development, demonstration, and deployment of Accelerator-driven Transmutation of Waste (ATW) from used nuclear reactor fuel. The concept of ATW is being examined in the U.S. because removal of plutonium and minor actinides from the used fuel, as well as iodine and technetium – two very long-lived (roughly one million year half-lives) isotopes that are candidates for transport into the environment via ground water movement – could achieve some important objectives. Plutonium would be nearly eliminated, the inventory and mobility of long-lived radio-nuclides in the repository would be reduced, and the energy content of the used fuel could instead be exploited in producing power. In this presentation Dr. Beller will discuss current philosophy for accelerator-driven transmutation, physics and other bases of transmutation, technology advances, and R&D challenges. He will describe ongoing research and development initiatives at the national laboratories, universities, and international institutes. Past, current, and future academic and international participation that is critical to the success of this project will be presented. He will also discuss alternate deployment scenarios (multi-tier approaches) in view of a renaissance in the U.S. nuclear industry and a change in recycling philosophy, and will report the current status of the AAA program. 
Bio: Denis E. Beller (Ph.D., Purdue Univ., 1986; M.S.N.E, Air Force Inst. of Tech., 1981; B.S.Ch.E., Univ. of Colorado, 1976) has a background in engineering design and analysis and in management of defense systems. Dr. Beller's research activities have included design and analysis of conceptual systems for nuclear effects testing with inertial confinement fusion, conceptual design of nuclear-pumped lasers, systems studies of long-term national and global deployment of nuclear energy, and formulation and testing of solid rocket propellants (including propellant formulations that were used in Operation Desert Storm). He also managed a rocket test facility, a nuclear detection laboratory that monitored radioactive emissions to support Safegaurd D of the Nuclear Test Ban Treaty, and an intelligence division that collected and disseminated foreign science and technology information. After graduation from Purdue in 1986, Dr. Beller was a professor at the Air Force Institute of Technology, where he taught graduate nuclear engineering (weapons effects) to military officers for more than seven years. As a result of teaching, research, and professional activities, the faculty selected him as the first tenured military professor in AFIT's 70-year history. Dr. Beller is currently enjoying a sabatical from Los Alamos to the Harry Reid Center for Environmental Studies at the University of Nevada, Las Vegas, where he coordinates university participation for the LANL AAA Program, UNLV, and other universities. He is best known amongst the nuclear science and technology community as the co-author of a Foreign Affairs essay that, according to the Congressional Record, “sparked renewed debate of nuclear energy’s role” as a non-emitting domestic energy source. Mark Porringa’s Candidate Techniques for Clean-Up of Nuclear Waste June 14, 2002, long-time friend, physicist, and email correspondent Andrew Michrowski, Ph.D., emailed Gary Vesperman two reports. Dr. Michrowski is with The Planetary Association for Clean Energy, Inc. (in French La Société planétaire pour l'assainissement de l'énergie, inc), 100 Bronson Avenue / Suite 1001, OTTAWA, Ontario K1R 6G8 (613) 236-6265 fax: (613) 235-5876 pacenet@canada.com http://pacenet.homestead.com.
The following is a reasonably comprehensive list of potentially effective nuclear waste treatment methods that might be employed to treat the entire range of radioactive wastes that have proven to be such a daunting and horrendously expensive problem for the nuclear industry (in all its forms) with major, long-term implications for the environment. A wide variety of methods will probably be required to accommodate the many different radioactive waste sources including high and low level, solids, liquids and gases. Process names used here are in some cases just convenient labels used to categorize and set them apart from each other.
Theories on several of these processes are still quite speculative and solid evidence that would pass conventional peer review is still lacking. This is after all a very new field of science. Some of these technologies are already well protected by international or national patents, with additional US and international patents pending, and further patents may be obtained on new developments as they are made. Photoremediation The Photoremediation process of the American Dr. Paul Brown is essentially conventional physics, albeit applied in a new and novel way. The process involves the use of a high-energy electron beam impinged on a target which in turn produces a monochromatic gamma radiation that is tuned to induce photofission and photoneutron reactions in the target material causing rapid neutralization of radioactive isotopes. The efficiency claimed exceeds 500% due to the high cross-section reactions in the giant dipole resonance region. The 10 million electron-volt (MeV) electron beam produces typical fission reactions in the 200 MeV range effectively turning high-level solid wastes such as spent fuel into an energy source. The process is apparently intended for on-site treatment with some waste-partitioning required, an aspect which may not be desirable in certain countries.
While this idea is similar in topology to a system being developed by Los Alamos National Labs, Dr. Paul Brown’s approach offers several advantages: no need for extensive chemical pre-processing and the energy required to effect transmutation is greatly reduced. No new technology needs to be developed, yet the engineering of such a photon reactor must be completed and it could itself become a practical method for generating power. For more see “Radioactivity Neutralization with Paul Brown’s Gamma Ray Method” in www.padrak.com/vesperman. Plasma Induced/Injected Transmutation Processes
Plasma induced/injected transmutation processes include a gamut from recent achievements dating back to the Oshawa-Kushi cold plasma transmutations reported in 1964. The patented High-Density Charge Cluster (HDCC) process was first discovered by Kenneth Shoulders and added on to by Harold E. Puthoff. Later, the late Stan Gleeson discovered HDCC in properly processed solutions. Still later, Alexander Ilyanok of Belarus discovered HDCC, followed by Vasiliy Baraboskin in Russia. The production of condensed charge clusters and various plasma glow discharge phenomena in a variety of gaseous atmospheres is again implicated as the underlying cause with what should be by now an obvious connection with the coherence of zero-point energy from the quantum or stochastic vacuum. Desk-top high energy particle accelerators have also been envisioned, based on the “piggy back” principle, in which the clusters permit acceleration of “piggy-backed” heaver +ions to extremely high energies capable of causing fusion and transmutations in target materials including those in solution and the materials of which the electrodes are composed. Brown’s gas implosion and cavitation bubble collapse reactions are also believed to be prevalent in these types of cells due to the prevalence of electrolysis.
A high-density charge cluster technology was discovered and used by Stan Gleeson to stabilize radioactive liquid wastes and has been developed further in the last 4 years by a group led by S-X Jin and Hal Fox. Best results for radioactive liquids have been demonstrated in the processing of thorium for a 30-minute period and achieving a reduction of radioactivity of about 90% from a liquid sample. Physicist Robert Bass, Ph.D., has a web site http://www.innoventek.com/. Its “Technology” section includes five articles on the Gleeson-Holloman LENT-1 Radwaste Remediation Reactor. LENT is an acronym for Low-Energy Nuclear Transmutation. His POC is Robert Bass Dallas, Texas (?) 702-387-7213 817-682-2655 817-377-7638 817-370-7109 |