PHY335 PROJECT PROPOSAL

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1 PHY335 PROJECT PROPOSAL 1 DETAILS OF PROPOSAL Organisation where grant would be held University of Sheffield Proposer Student registration number Title of Research Project (Please do not exceed 108 characters, including spaces.) Decontamination and disposal of low-level radioactive waste using ionexchange resins and plant extraction Summary of Financial Resources Required for Project Total Travel and subsidence Consumables 2300 Staff Costs Equipment Total Duration Duration of the grant (months): 36 1

2 Objectives List main objectives of the proposed project in order of priority. These objectives should be those which you would wish to have used in the evaluation of your work. Determine whether plants can live in an ion exchange resin Determine or predict the time scale required to regenerate an ion exchange resin using platn extraction Choose plants and design resins as the basis for future development work Summary Describe the proposed project in about 200 words. Ion-exchange resins are expensive but are powerful at removing radioactive contaminants. This project seeks to regenerate the resins, so that they can be reused, and to reduce the volume of low level radioactive waste. Plants that extract radioactive particles from soil and water, accumulating the contaminants in their leaves, will be transferred to resins. Thus a resin capable of supporting plant life is to be developed. This will result in a method of concentrating low-level radioactive waste into a lower volume, which has the environmental and cost benefits of saving space in disposal sites. It would make resins cost effective, meaning that a more powerful decontamination agent would be accessible to hospitals and industry. In the event of spillages or other disasters, the improved power would mean improved safety. by reducing cleaning time which in turn reduces exposure to the radioactive contaminant. Beneficiaries Describe who will benefit from the project. British Nuclear Fuels / British Nuclear Group British Energy plc United Kingdom Atomic Energy Authority Department for Environment Food and Rural Affairs (Also Department of Health, Health and Safety Executive, Environment Agency) Ministry of Defence National Health Service Private sector hospitals (e.g. BMI Healthcare) Academic nuclear/medical/radiation physics research departments (e.g. Nuclear Physics Group at CCLRC Daresbury Laboratory, Centre for Nuclear and Radiation Physics at University of Surrey). 2

3 Travel and Subsidence Destination and purpose Total Meetings of The Department of Physics and Astronomy, The Department of Animal and Plant Sciences (both of Sheffield), and The School of Chemical Engineering and Advanced Materials (Newcastle). Held at either University to discuss progress and ensure the quality of research. Up to 12 a year, 200 each including travel costs for three members of staff Assistance with living costs and travel expenses for PhD studentship Total Consumables Specify Total Raw materials for ion-exchange resins (synthetic organic materials) 1800 Nutrients and additives 500 Total 2300 Exceptionable Items Specify Total PhD Studentship (environmental engineering) Post Doctoral Researcher (laboratory supervision, measuring) Total

4 Equipment (single items under 100,000) Description of items and country of Basic manufacture Price Import Duty VAT Total Disposal costs for low-level radioactive waste, internal to University of Sheffield 40,000 N/A Production of ion exchange resins, outsourced to The University of Newcastle-upon-Tyne. 60,000 N/A 10, Total

5 2 CASE FOR SUPPORT Key words: phytoremediation, phytoextraction, decontamination agents, ionexchange resins, low-level radioactive waste. Decontamination agents, in the case of low-level radioactive waste, lift ionised heavy metals from contaminated surfaces and are used to clean equipment and handle spillages. Existing, safe products such as "radiacwash" are only slightly more effective than water, and soaking is often required to clean surfaces properly[1]. In spite of this, there has been a market for such cleaners in hospitals, laboratories and nuclear power plants. A new decontamination agent with improved power but low toxicity could in itself make an impact on this market. Successful uptake of an improved agent by the market might be possible even if it is more expensive, because more powerful decontamination agents remove contaminants faster, thereby reducing exposure to them. This is critical in clean-up operations, especially emergencies such as personal contact with radioactive material. Safety should be top priority in any industry, but it is utterly crucial in the target market: those handling radioactive materials. Accidents in this context can be very costly and damaging. However, in some settings the risks of contamination will be low, and there may not be enough incentive to move to a more expensive product. Such can be said of ion exchange resins. Common in other decontamination and cleaning settings, they have been demonstrated to be much more effective than existing products in cleaning contaminated surfaces. Ion exchange resins are already used in numerous industrial processes involving radioactive isotopes, such as water treatment plants and Uranium enrichment. Traces of an isotope can be concentrated in the resin. Yet such resins are very expensive. At present, radioactive ion exchange resins have to be chemically destroyed[2] and disposed of as low-level radioactive waste. The answer is to reclaim as much of the resin as possible, so that the reclaimed resin can be used again. The material which takes the radioactive isotopes out of the resin must itself be of a low cost. It must not leave the radioactive isotopes in a less concentrated form, as this increases the volume of waste and disposal of low-level radioactive waste is extremely expensive. This is where phytoextraction (plant extraction) offers an opportunity. Extracting radioactive heavy metals from soil[3] or water[4] using plants has already proved to be effective and concentrates the contaminants. The development of a resin which supports such a plant would allow the resin to be recycled and would harness the benefits of phytoextraction beyond soil and water cleaning. With the contaminants concentrated in the plant material, there would be a small volume of radioactive waste, especially so because it possible to further process the plants. This leads to a saving on the costs of disposal - and space in radioactive waste disposal sites. The resin itself is made available for reuse, compounding the savings 5

6 There are some disadvantages to phytoextraction, but they are much less important in this context: Phytoextraction can be a relatively slow process which is a problem when cleaning up environmental emergencies. But in the proposed system, the powerful decontaminating agent cleans quickly, and the phytoextraction itself takes place in a confined industrial setting. Introducing plants into an ecology to decontaminate soil and groundwater can have an environmental impact, and so the plant must be chosen very carefully. Again however, the resin supported plants will not be used in a natural habitat. Programme and Methodology This research proposal is "proof of concept" in nature. Demonstrating the possibility of using plants to regenerate resins would be a significant step forward in industrial chemistry. It should hopefully not be necessary to genetically modify existing plants to achieve some success. While genetic modification might improve the process, this project need only determine feasibility. Creating genetically modified plants would increase the amount of testing required and lead to negative public opinion, although the plants are not be used in food or the environment. It is therefore best to identify an existing plant and cater the resin for that plant. It should be possible to add nutrients etc. to the resin during processing. If necessary, additives can be removed after phytoextraction by using traditional resin regeneration techniques. Existing resins that are successful in cleaning up low-level radioactive waste will be used as the basis for new designs. The Department of Animal and Plant Sciences will identify any problems that these resins have in supporting healthy plants. The School of Chemical Engineering and Advanced Materials at the University of Newcastle upon Tyne will subsequently design the modified candidate resins. Newcastle and the Animal and Plant Sciences department will also collaborate to select any additives which could be used. Additives will be chosen which are not expected to negatively affect the performance of the resin, or otherwise a technique for chemically regenerating the resin to eliminate the additive will be identified where possible. It is likely that small quantities of prototype resins will be produced during this stage and very basic experiments performed to check progress. Once candidate plants have been selected and resins designed, preliminary trials can be prepared. The purpose at this stage is to successfully sustain the plants in the resin, resin regeneration only being a desirable at this stage. Sample resins will be produced at Newcastle for Sheffield. The Department of Physics and Astronomy will then test the resins for their cleaning capabilities. Any that do not show better decontaminating power than "radiacwash" will be rejected. These experiments will have contaminated some resin in preparation for the preliminary phytoextraction trials. Nevertheless, both contaminated and uncontaminated resin will be tested for their ability to support the plants. This will help assess the affects of the resin and contaminants on the plants separately. 6

7 The preliminary trials will be housed in the University of Sheffield's Health and Safety Laboratory. This is a secure, modern building already well equipped for environmental engineering and multidisciplinary work, including sophisticated plant growth rooms. The health of the plants will be assessed daily by Animal and Plant Sciences, while the concentration of contaminants in the resin and in the plants will be monitored by Physics and Astronomy. There will also be a PhD student present throughout the trials, who would have been in Newcastle during design and production of the ion-exchange resins. All aspects of the experiment will be supervised by Physics and Astronomy to ensure the safety of staff and that the correct procedures concerning radioactivity are followed. All researchers will be trained in radioactive material and waste handling where required. It should be considered sufficient for the plants to survive or flourish in the uncontaminated resin for at least 6 weeks, and as long as possible in the contaminated resin. Adjustments to the resin formula can be made, and retrials held, as required to achieve success in the preliminary trials. Once the more promising combinations of resins and plants have been identified, it is time to rigorously test the response of plants at various contamination levels and to measure their performance in extracting and accumulating the contaminants. It is important to determine the time scale for resin regeneration. Both keeping the same plants in the resin for extended periods and replacing the plants once and twice every six months will be tested. Milestones and timetable: 1. Detailed analysis of existing plants and resins; potential candidates to have been selected. Orientation of PhD student (2 months) 2. Design and improvement of the resin and additives for supporting plants (5-8 months) 3. Testing for resin cleaning capability and preliminary phytoextraction trials; adjustments to the resin and retrials as required (4-8 months) 4. Test for plant response to contamination level and performance in phytoextraction. Determination of timescale for resin recovery (at least 18 months, until project end) Relevance to beneficiaries Waste disposal is becoming increasingly regulated and expensive, and disposal of radioactive waste carries a very high cost both financially and for the environment. Reducing these, together with improving safety with a more efficient decontaminating agent, offers considerable incentives for industry and government. Low level radioactive waste makes up about two-thirds of the total radioactive waste produced in the UK. 7

8 Companies such as British Nuclear Fuels are responsible for safe disposal of radioactive waste in dedicate sites, whilst Defra is the main regulating government organisation. The Ministry of Defence is interested in disposal methods due to their maintenance of nuclear weaponry and submarines. Hospitals, which use radiation therapy, industry and academic departments all produce low-level waste which is expensive to dispose of. The possibility of revolutionising and improving the handling of low-level radioactive waste is also in the general public interest. Dissemination and exploitation Due to the public interest in radioactive waste handling and novel nature of the research, publication in a high profile journals would be sought. The complete results would be published in detailed form in the supervised PhD student thesis. Since the project is for the public good, and has wide-spread interest for many parties, the universities will relinquish intellectual property rights which are to be dedicated into the public domain. In any case, no final product is to be produced by this project, therefore patents are unlikely to prevent further work by third parties. Indeed, the latter is to be encouraged, as commercial competition will allow development of better resins and, possibly, the genetic modification of the plants to improve performance. There would be the potential for expansion in the long term. A generation of resins might follow for other applications e.g. those mentioned above: water treatment, Uranium enrichment. Phytoextraction could save costs throughout nuclear industry and reduce environmental impact. There is also the potential to develop phytoextraction (or other phytoremediation processes) for resins outside of nuclear waste management. Justification of Resources The multidisciplinary nature of this project requires experts in radiation physics, chemical engineering and plant biology. Resins are expensive to make and trials could take several months or longer. It is therefore crucial to design the candidate resins carefully. The expertise and equipment at Newcastle will ensure that the design and small-scale production of the ion-exchange resins will be of a high quality without wasting raw materials and time. It is also necessary for the three departments to meet regularly. This will ensure that progress and problems can be thoroughly discussed, that expertise can be shared and appropriate training undertaken. To save on costs and visit the laboratories, each meeting can be held at one of the two Universities. There would also be a PhD studentship in environmental engineering. The student would have the time to become truly familiar with the various aspects of this multidisciplinary project, and spend considerable time with each department. This would bring cohesiveness to the project and continuity between each stage. As travelling would be required, and to attract and retain a high quality PhD student, an allowance for living costs and travelling expenses would be given. The laboratory and handling/measurement of radioactivity would be supervised by a researcher, to ensure the safety of the PhD student and other staff. 8

9 References to Previous Work [1] Kuperus et al. "Radiological Decontamination: Lab Demonstration on Various Surfaces using Ion-Exchange Technology". Waste Management Conference 2004, Tuscan Arizona. [2] Taylor. "Destruction of Ion-Exchange Resin in Waste from HFIR, T1, and T2 Tanks Using Fenton's Reagent" DOE [3] Botany Issues Map. "Phytoremediation: Using Plants to Clean Soil" [4] Centre for Public Environmental Oversight 9