DIAMOND: Decommissioning, Immobilisation And Management Of Nuclear wastes for Disposal

保守估计，过去60年英国民用核项目的遗留废物处理和处置，以及退役和场地修复，将花费英国纳税人700亿英镑。在解决这个问题的过程中，必须解决的问题种类繁多，需要从同样广泛的技术学科领域中汲取广泛的创新解决方案。拟议的研究计划分为三个工作包（WPs）：(1)环境，迁移和风险；(2)退役、历史遗产和遗址终止；(3)材料——设计、开发和性能。WP 1：环境、移民和风险清理受污染土地是核设施恢复的重要组成部分。目前存在的放射性污染物的范围以及潜在的混合污染是一项重大挑战。特别是，可溶性和胶体物质在地下迁移的潜力是确定位点终点的关键不确定性。目前，大多数清理工作都是通过侵入式技术进行的；因此，我们将探索更具成本效益的原位技术，如屏障处理系统。与地质处置固定放射性废物有关的许多不确定因素和技术挑战严重取决于工程设施的释放速度，以及放射性核素随后在扰动区和远场的行为。工作包2：退役，历史遗产和场地终止燃料储存和处理设施中存在的异质废物是该联盟的关键目标。这些废物包括辐照燃料、受污染的材料和腐蚀产物。总的体积和成分（化学和放射性）知之甚少，尽管据信每个主要储存池中有几百立方米。因此，改进和准确的表征是一个优先事项，并提出了新的检索和治疗技术。此外，历史活动产生了少量的孤儿废物，没有明确的管理途径；它们的多样性需要新的和通用的治疗方法，这些方法将在本方案中发展。我们还把重点放在放射性核素清单的量化、通过工程途径的污染物运输和废物回收等我们可以作出进一步贡献的领域。工作包3：材料-设计，开发和性能地质处置已被政府接受为英国放射性废物长期管理的最佳方法，并得到强有力的临时储存计划的支持。因此，本工作计划的研究重点是解决废物调节、储存和处置方面的关键知识差距，以便为废物管理方面的未来决策提供基础。研究基于三个关键主题，旨在：1)了解辐射和辐射溶解对核陶瓷在临时储存期间稳定性的影响；2)了解乏燃料、钢包装和高放玻璃在贮存和处置条件下的腐蚀机理；3)开发新的材料和加工路线，灵活地固定各种废物，包括燃料碎片和石墨，以适合储存和处置的形式。这项工作的另一个方面将是开发新的合成路线，以生产先进的惰性基质燃料。

Legacy waste treatment and disposal, as well as decommissioning and site remediation, from the last 60 years of the UK's civil nuclear program are conservatively estimated at a cost of 70B for the UK taxpayer. The diversity of issues that must be addressed in tackling this problem is immense and requires a wide range of innovative solutions drawn from an equally wide range of technology discipline areas. The proposed research program is divided into three work packages (WPs): (1) Environment, Migration and Risk; (2) Decommissioning, the Historic Legacy and Site Termination; and (3) Materials - Design, Development and Performance.WP 1: Environment, Migration and RiskCleaning up contaminated land is a substantial component of nuclear site restoration. The range of radioactive contaminants present, and the potential for mixed contamination, represents a major challenge. In particular, the potential for migration of soluble and colloidal species in the subsurface is a key uncertainty in defining site end points. Currently, most cleanup is expected to be through invasive technologies; hence, we will explore more cost-effective in situ technologies such as barrier treatment systems. Many of the uncertainties and technical challenges associated with geological disposal of immobilised radioactive wastes are critically dependent on the rate of release from the engineered facility, and on the subsequent behaviour of the radionuclides in the disturbed zone and the far field. Work Package 2: Decommissioning, the Historic Legacy and Site TerminationHeterogeneous wastes present in fuel storage and handling facilities are a key target of the consortium. These wastes comprise irradiated fuel, contaminated materials and corrosion products. Total volumes and compositions (both chemical and radioactive) are poorly known, although there are believed to be several hundred m3 in each of the main storage ponds. Improved and accurate characterisation is therefore a priority, and novel technologies for retrieval and treatment are proposed here. In addition, historical activities have created small volumes of orphan wastes for which no clear management route exists; their diversity requires new and versatile treatment methods which will be developed in this programme. We also focus on the quantification of radionuclide inventories, contaminant transport through engineered pathways and waste retrieval as areas where we can make a further contribution.Work Package 3: Materials- Design, Development and PerformanceGeological disposal has been accepted by Government as the best available approach for the long term management of UK radioactive wastes, supported by a robust programme of interim storage . The focus of research in this WP is therefore to address key knowledge gaps in the conditioning, storage and disposal of wastes in order to underpin future decision making in waste management. Research is based on three key themes, aimed at: 1) understanding the effects of radiation and radiolysis on the stability of nuclear ceramics during interim storage; 2) understanding the corrosion mechanisms of spent nuclear fuels, steel packaging and HLW glasses under conditions of storage and disposal; 3) development of new materials and processing routes with the flexibility to immobilise a spectrum of wastes, including fuel debris and graphite, in a form suitable for storage and disposal. A further aspect of this WP will be development of new synthetic routes to advanced inert matrix fuels.