Feasibility of the use of frozen walls in molten salt fast reactors (MSFR-FW)

在熔盐快堆（MSFR-FW）中使用冷冻壁的可行性

• 批准号: EP/R001618/1
• 负责人: Charles Moulinec
• 金额: $ 25.71万
• 依托单位: Science and Technology Facilities Council
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FR001618%2F1
• 关键词: Feasibility; use; frozen; walls; molten

The overall challenge for the future energy supply is given in UN Goal 7: Ensure access to affordable, reliable, sustainable and modern energy for all is one of the major challenges for the future of human being. The Research Councils UK Energy Research Program describes the problem as the energy 'trilemma' consisting of the challenges to reduce emissions, enhance security of supply, and reducing the cost. Disruptive innovation seems to be the only way to tackle the energy 'trilemma'.Nuclear reactor technologies have the potential to deliver a promising solution for this challenge. However, the current nuclear energy system is dominated by Light Water Reactors which are not ideal for the required growth in energy production, since their long term operation is not sustainable due to the insufficient use of the natural uranium. The spent nuclear fuel from these reactors still contains ~95% of its original energy content when it is unloaded and considered as waste further on. Making use of the energy content remaining in the spent fuel by closing the nuclear fuel cycle can provide an almost unlimited energy resource. In addition, it can provide a promising use of the Pu stockpile, an unused energetic asset, which is a leftover from the first attempt to achieve a closed fuel cycle in the nuclear system in UK. From an economic point of view, the Pu stockpile is seen as burden due to the requirement of safeguarded storage. Pu utilization could transform this still existing energetic asset into an economic asset.The objective of this feasibility study is to assess the applicability of frozen wall technology to molten salt fast reactors which is a key technology for this kind of highly innovative reactors. The core of molten salt reactors is designed such that there are no internal vessel structures and that the fuel dissolved in the salt to achieve a critical mass therein. The fuel is pumped through a number of external heat exchangers to extract the heat to be converted to electrical power. Small quantities of fuel salt are continuously fed and withdrawn from the reactor to allow the separation of unwanted fission products from the salt before being recycled into the core. Consequently, as the fuel salt is liquid, it requires less processing before and after use with smaller on site inventories of fuels and waste. A 3 GWth (1-1.5 GWe) reactor is proposed as a direct burner of the spent nuclear fuel accumulated from 60+ years of nuclear power generation in the UK. Thus, the MSFR is intended as an affordable, reliable and sustainable supply of low carbon electrical power that can convert an economic and social burden into an economic asset. One of the key technical challenges in developing molten salt reactor concepts is that the molten salt corrosively attacks almost all materials at the operating temperatures expected in the reactor. The high neutron flux expected in the MSFR is also known to embrittle structural materials. This study is intended to determine whether the use of frozen wall technology is feasible method of protecting the reactor vessel from corrosive attack, before we can proceed with further studies of design concepts.To assess the feasibility of frozen wall technology, numerical models of the turbulent thermal hydraulics of the 3 GWth reactor vessel will be coupled to structural models of the vessel wall and the neutron transport. The coupled models will enable us to make observations of regions where the power production contributes to the temperature of the molten salt, which in turn will influence the temperature at the interface between the salt liquidus and solidus interfaces. We will be able to determine regions of thick and thin frozen film depths in order to specify how much cooling is required to maintain the salt film to protect the materials and to propose design modifications that can stabilise the flow and reduce the influence of strong temperature gradients expected over the reactor height.

联合国目标7提出了未来能源供应的总体挑战：确保所有人都能获得负担得起的、可靠的、可持续的现代能源是人类未来的主要挑战之一。英国研究委员会能源研究计划将这个问题描述为能源“三难困境”，包括减少排放、加强供应安全和降低成本的挑战。颠覆性创新似乎是解决能源“三难困境”的唯一途径。核反应堆技术有可能为这一挑战提供一个有希望的解决方案。然而，目前的核能系统以轻水反应堆为主，这种反应堆不适合能源生产所需的增长，因为由于天然铀的使用不足，它们的长期运行是不可持续的。从这些反应堆中取出的乏燃料在卸下并被进一步视为废物时，仍含有约95%的原始能量含量。通过关闭核燃料循环，利用乏燃料中剩余的能量，可以提供几乎无限的能源。此外，它可以提供一个有前途的使用钚库存，一个未使用的高能资产，这是遗留下来的，从第一次尝试实现一个封闭的燃料循环在英国的核系统。从经济角度来看，由于需要有保障的储存，浦江堆被视为一种负担。Pu的利用可以将这种仍然存在的有活力的资产转化为经济资产。冻壁技术是熔盐快堆的关键技术之一，本可行性研究的目的是评估其在熔盐快堆中的适用性。熔盐反应堆的核心被设计成没有内部容器结构，并且燃料溶解在盐中以达到其中的临界质量。燃料通过一些外部热交换器泵送，以提取热量并转化为电能。少量的燃料盐不断地从反应堆中输入和取出，以使不需要的裂变产物从盐中分离出来，然后再循环进入堆芯。因此，由于燃料盐是液态的，它在使用前后需要较少的处理，现场燃料和废物的库存也较少。一个3gwth （1-1.5 GWe）的反应堆被提议作为英国60多年核电积累的乏燃料的直接燃烧器。因此，MSFR是一种可负担、可靠和可持续的低碳电力供应，可以将经济和社会负担转化为经济资产。开发熔盐反应堆概念的关键技术挑战之一是，在反应堆预期的工作温度下，熔盐对几乎所有材料都具有腐蚀性。MSFR中预期的高中子通量也已知会使结构材料脆化。本研究旨在确定使用冷冻壁技术是否是保护反应堆容器免受腐蚀的可行方法，然后我们才能进行进一步的设计概念研究。为了评估冻结壁技术的可行性，将3gwth反应堆容器的湍流热工数值模型与容器壁和中子输运的结构模型相耦合。耦合模型将使我们能够观察到电力产生对熔盐温度有影响的区域，而熔盐温度反过来又会影响盐液和固相界面之间的界面温度。我们将能够确定厚和薄冷冻膜深度的区域，以便指定需要多少冷却来维持盐膜以保护材料，并提出设计修改，以稳定流动并减少对反应堆高度预期的强温度梯度的影响。

项目成果

Molten chloride fast reactor draining transients

熔融氯化物快堆排水瞬变

• 发表时间: 2020
• 作者: Cartland Glover G

Effect of Surface Temperature on Rarefied Flow Past a Circular Micro-Cylinder

表面温度对通过圆形微圆柱体的稀薄流动的影响

• DOI: 10.1115/mnhmt2019-4232
• 发表时间: 2019
• 作者: Gu X

Evaluation of the Breeding Performance of a NaCl-UCl-Based Reactor System

NaCl-UCl 基反应器系统的育种性能评估

• DOI: 10.3390/en12203853
• 发表时间: 2019
• 期刊: Energies
• 影响因子: 3.2
• 作者: Merk B

MODELLING FROZEN SALT FILMS IN A MOLTEN SALT FAST REACTOR

熔盐快堆中冷冻盐膜的建模

• 发表时间: 2018
• 作者: Cartland-Glover G.M.

On the feasibility of the application of frozen walls to a molten salt fast reactor,

论冷冻壁应用于熔盐快堆的可行性

• 发表时间: 2018
• 作者: Cartland-Glover GM