Developing technology and specifications for metakaolin-based geopolymers as robust and promising stabilisers for fuel debris removal

开发偏高岭土基地质聚合物的技术和规格，作为燃料碎片清除的强大且有前途的稳定剂

• 批准号: EP/Y029208/1
• 负责人: Brant Walkley
• 金额: $ 52.37万
• 依托单位: University of Sheffield
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FY029208%2F1
• 关键词: Developing; technology; specifications; metakaolin; based

Past and ongoing decommissioning and cleanup operations at both the TEPCO Fukushima Daiichi Nuclear Power Plant and Sellafield site has generated significant quantities of complex radioactive waste streams. This includes solid fuel debris waste fragments comprising mainly molten core concrete interaction products, which include a variety of materials such as metallic alloys, oxides, and silicates, and slurries and sediments containing fine particles or colloids, which are variously rich in metal carbonates, ferric oxide, and/or barium sulphate. New solidification and stabilisation methods are therefore urgently required to enable safe disposal of these waste streams.This project will use calcined clays as natural resources to engineer geopolymer binders, with and without boron as a neutron absorbent, to provide a robust and future-proof waste cementation matrix for long-term management and disposal of degraded fuels and contaminated wastes in Japan and the UK. This will broaden the formulation envelopes to increase waste loading and compatibility with wastes that cannot be effectively treated by conventional cementation.Geopolymer cements are produced via the chemical reaction between a source of alkalis (the "activator"), which is usually supplied as an aqueous solution, and a "precursor" powder that supplies silicate and aluminate for the reaction process. Geopolymer cements have been highlighted in technical and road-mapping publications in both the UK and Japan as offering very high potential for use in the treatment and disposal of diverse and problematic wastes. In particular, geopolymer production using calcined clays as the main precursor has been identified as offering the possibility for excellent technical performance as a waste conditioning matrix, controllable in the fresh and hardened states, while removing the reliance of the nuclear sector on conventional cementitious powders that will become increasingly scarce in the coming decades.We will identify and optimise geopolymer binder formulations that are robust to variations in the nature and characteristics of clay-derived and other precursors, including in terms of easy manufacturing (including desirable flow characteristics such as viscosity, yield stress, controlled thixotropy, and flow retention), radionuclide encapsulation (both cationic and anionic radionuclides), and encapsulation of complex waste streams such as solid waste fragments and slurries/sediments. This will underpin the use of geopolymers as a key part of the toolkit of cements that are needed to meet the remediation and decommissioning needs of the UK, Japan, and other countries worldwide. The project has strong bilateral UK and Japan links, incorporating expertise from both universities and the Japan Atomic Energy Agency (Japan) and Sellafield Ltd. (UK).

Tepco Fukushima Daiichi核电站和Sellafield遗址的过去和正在进行的退役和清理操作都产生了大量复杂的放射性废物流。这包括固体燃料碎屑废物碎片，其中包括主要是熔融核心混凝土相互作用产品，其中包括各种材料，例如金属合金，氧化物和硅酸盐，以及含有精细颗粒或胶体的浆液和沉积物，这些材料富含金属碳酸盐，氧化三碳和/或/或硫酸氢。 New solidification and stabilisation methods are therefore urgently required to enable safe disposal of these waste streams.This project will use calcined clays as natural resources to engineer geopolymer binders, with and without boron as a neutron absorbent, to provide a robust and future-proof waste cementation matrix for long-term management and disposal of degraded fuels and contaminated wastes in Japan and the UK.这将扩大配方信封，以增加无法通过常规胶结有效治疗的废物的废物负荷和兼容性。地球聚合物水泥是通过碱（“激活剂”）之间的化学反应产生的，该反应通常被供应作为水溶液和“前体溶液”和“先前溶液”的粉末粉的粉状和层压反应。在英国和日本的技术和道路图出版物中，地质聚合物的水泥在处理和处置多种和有问题的废物方面具有很高的潜力。特别是，使用刻板的粘土作为主要前体的地质聚合物的生产已被确定为具有出色的技术性能作为废物条件矩阵的可能性，在新鲜和坚硬的状态下可控，同时可以控制核部门对常规水泥粉的依赖的依赖，从而在未来几十年中越来越稀少，以使我们的特征越来越多。粘土衍生的和其他前体，包括在易于制造方面（包括粘度，屈服应力，受控的触变和流量保留），放射性核素的封装（阳离子和阴离子放射性核素）以及诸如固体废物片段和泥浆和泥浆的复杂废物流。这将支持将地球聚合物用作水泥工具包的重要组成部分，以满足英国，日本和全球其他国家的补救和退役需求。该项目具有强大的双边英国和日本链接，并结合了大学和日本原子能局（日本）和塞拉菲尔德有限公司（英国）的专业知识。