压水堆核电厂选址假想事故初步研究

简要介绍了核电厂选址假想事故的发展过程,比较了基于RG 1.183和RG 1.195选址假想事故源项的计算假设,结合AP1000和CPR1000两种堆型计算了选址假想事故源项,同时结合某核电厂址计算了对公众造成的辐射影响。计算结果表明:1)参照RG 1.183计算假设,AP1000和CPR1000核电厂公众受照剂量最大的两小时分别为事故后1.25~3.25 h和0.7~2.7 h;2)无论参考RG 1.183还是RG1.195计算假设,CPR1000对公众造成的辐射后果要小于AP1000;3)无论是AP1000还是CPR1000,参照RG 1.183比RG 1.195计算得出的选址假想事故源项对公众造成的辐射后果均较小。     

泳池式低温供热堆选址假想事故及其源项研究

<正>泳池式低温供热堆(简称供热堆)是针对北方城市供暖需求开发的一种安全经济、绿色环保的新型供热系统。现在计划建造供热堆示范工程,需确定选址假想事故及其源项。供热堆堆芯位于水池底部,始终处于淹没状态;在任何事故下,依赖反应堆固有负反馈特性可实现自动停堆;停堆后不采取任何余热冷却手段,堆水池内的水可确保堆芯长时间不裸露。针对供热堆的设计特点,从超设计基准事故分析和概率     

核动力厂与环境

目前世界上已有28个国家和地区已有或正在建造核电厂。截至1991年12月31日,全世界运行中的核电机组共有422套,总装机容量达328GW,其中美国的装机容量最多,核电厂发电量占比例最大的是法国。美国三里岛和苏联切尔诺贝利核电厂     

压水堆核电厂事故后厂房内气载放射性源项计算

事故工况下辐射防护设计是核电厂辐射防护设计的重要方面,事故后辐射源项作为事故后辐射分区以及人员剂量率评价的重要输入,其计算模型的确定是事故后辐射防护设计中最重要的部分。本文根据设计基准事故放射性后果的严重性,选取大破口失水事故(LOCA)开展事故后辐射防护设计,自主建立事故后气载放射性物质的扩散模型,并验证了源项计算模型的正确性。     

CARR事故放射性源项分析

采用ORIGEN2程序对CARR核功率为60 MW、运行50 d计算得到堆芯放射性核素的贮量,建立事故情况下放射性核素从燃料芯块向环境释放的数学模型,并根据CARR初步事故分析的结果,对CARR可能导致在发生事故时向外界释放放射性的5种事故工况:小破口失水事故、换热器传热板     

压水堆核电厂蒸汽发生器传热管道破裂事故源项的计算分析

当压水堆核电厂发生事故后,带有放射性的核素会通过破损处释放到环境中,从而危害核电厂周边环境及相关人员的安全,因此对事故后释放到环境中的放射性源项分析,对于核电厂的辐射防护具有重要意义。本文根据事故发生的频率以及后果严重程度,选取蒸汽发生器传热管破裂事故(Steam Generator Tube Rupture,SGTR)进行分析。事故分为事故前碘尖峰释放和事故并发碘尖峰释放两种事故工况,建立事故后放射性核素迁移和扩散计算模型,同时使用先进压水堆AP1000参数进行计算验证,并重点关注惰性气体和挥发性核素碘在环境中的放射性活度。计算结果显示:使用文中计算模型计算的放射性源项与设计源项比较一致,在两种工况下,惰性气体的释放活度与设计源项吻合较好,但碘的释放活度有明显差别。     

熔盐堆选址源项确定方法评价研究

选址源项的种类成分、形态、数量、释放方式和释放时间、影响范围等参数是反映反应堆安全的重要指标。我国现行核安全法规对于反应堆选址源项仅有原则性规定,且多基于压水堆,不能完全适用于固态燃料熔盐堆。熔盐堆采用了不同于压水堆的设计、燃料、冷却剂和系统结构,因此,固态燃料熔盐堆的选址源项及其确定方法也与压水堆有很大不同。本文将结合核电厂选址相关的法规标准和核安全审评要求,对固态熔盐堆所采用的新设计理念、新燃料和结构系统特点进行分析,并对其选址源项及确定方法进行评价,为将来固态熔盐堆核电厂选址评价及有关核安全法规标准修订完善提供建议和参考。     

核动力装置的事故诊断系统

本文基于事故处置规程研究了核动力装置的事故诊断问题。通过对规程中事故诊断程序的分析,建立事故-征兆映射体系的数学模型,清晰地描述了征兆与事故之间的映射关系;基于事故-征兆矩阵提出了缺失有效数据诊断事故的方法,阶段I利用矩阵筛选出可能的事故集合,阶段II通过计算观测矢量与参考矢量间的几何距离评价阶段I的筛选结果;最后,基于两阶段判别设计了核动力装置事故诊断系统,并连接事故仿真程序PCTRAN/PWR,进行了在线仿真诊断测试,验证了事故诊断系统的有效性。     

苏联核动力厂安全标准

本文在业经核准的组织机构及现有规定标准文件系统的基础上,概述有关国家在保证核动力厂安全中的调节作用及核动力厂安全问题主要文件的内容     

Underground nuclear power plant siting

This paper summarizes the results of investigations to define the design concepts and estimate cost penalties associated with the burial of large light-water reactor nuclear power plants in underground rock cavities. Several cavities are proposed to contain the major components of the power plant without requiring excessive spans. The cost penalty of the underground plant is estimated to be less than 10% above a similar surface plant in favorable geologic media. Preliminary analyses also indicate a potential improvement in containment of radioactive materials following a postulated accident.     

Risk-benefit evaluation of nuclear power plant siting

An assessment scheme is described for the risk-benefit analyses of nuclear power versus conventional alternatives. Given the siting parameters for the proposed nuclear plant an economic comparison is made with the most advantageous competitive conventional production scenario. The economic benefit is determined from the differential discounted annual energy procurement cost as a function of the real interest rate and amortization time. The risk analysis encompasses following factors: radiation risks in normal operation, reactor accident hazards and economic risks, atmospheric pollutants from the conventional power plants and fuel transportation. The hazards are first considered in terms of probabilistic dose distributions. In the second stage risk components are converted to a compatible form where excess mortality is used as the risk indicator. Practical calculations are performed for the power production alternatives of Helsinki where district heat would be extracted from the nuclear power plant. At the real interest rate of 10% and amortization time of 20 yr the 1000 MW(e) nuclear option is found to be $9.1 m per yr more economic than the optimal conventional scenario. Simultaneously the nuclear alternative is estimated to reduce excess mortality by 2–5 fatal injuries annually.     

Investigation of the development of the 1986 accident at the Chernobyl nuclear power plant

Important results obtained from investigations of the diverse processes that occurred during the accident in the No. 4 unit of the Chernobyl nuclear power plant on April 26, 1986 are presented in a concise form. The events occurring in the unit in connection with the preparation for runout tests to be performed on a turbogenerator are examined: from the characteristics of the test program to the actions taken by the plant personnel in preparation for the these tests. The events that determined the character of the evolution and the catastrophic consequences of the accident are noted: involuntary stopping of the reactor and subsequent power increase without unpoisoning of the core, stopping of feed-water flow with increasing loop flow, operators’ lack of information about the actuation of the technological shielding of the electric drives of the main circulation pumps and electricity generator. Computational analysis of the initial phase of the accident and other computational assessments revealed new factors which with a large void effect made reactor runaway on prompt neutrons unavoidable-cavitation steam reaching the core entrance from the shutoff-regulation valve and/or the cavitation shutdown of the feed to the remaining main circulation pumps after the pumps powered by the run-out turbogenerator were disconnected. The most likely picture of the evolution of the accident is constructed on the basis of an examination of the destroyed power-generating unit. __________ Translated from Atomnaya énergiya,Vol. 100, No. 4, pp. 243–258, April, 2006.     

核电厂全厂断电事故分析

全厂断电（SBO）可能发展成为堆芯熔化、安全壳超压失效的严重事故。本文首先研究全厂断电事故的必要性以及在辅助给水系统不可用情况下的全厂断电事故的进程,随后定性的分析了事故进程在主泵轴封泄漏和对一回路实施减压缓解措施的影响下所具有的不同的发展情况。最后以秦山核电厂为例对其在提高应对全厂断电事故的能力和改进缓解事故后果的措施方面提出了建议。     

Radioecology and the accident at the Chernobyl nuclear power plant

The ecological features of the 1986 Chernobyl accident and the principles of radiation monitoring of the environment are described. The laws of migration of radionuclides in different media in the environment and the accumulation of radioactive substances in food products are presented. The effect of radiation on the plant and animal worlds in the region of the accident is assessed. A system of protective and remediation measures in the agricutural, forestry, and water spheres is presented, and their radiological and cost effectiveness are estimated. The significance of the complicated and contradictory political and economic conditions during the time of the accident in the USSR (Commonwealth of Independent States) for the assessment of the ecological consequences of the accident is indicated. __________ Translated from Atomnaya énergiya, Vol. 100, No. 4, pp. 267–276, April, 2006.     

某核电厂核事故应急演习经验反馈

日本福岛核事故的发生对全球范围核电行业的核应急演习提出了更高要求。本文结合电厂工作实际,就福岛事故后核应急演习新要求及经验反馈进行了总结,供从业人员参考。     

核电厂选址及环境影响评价应关注的问题

结合近年来我国核电厂选址工作,根据核安全以及环境保护的有关法规要求,重点分析了我国核电厂选址及环境影响评价的特点,并提出了我国核电厂选址及环境影响评价应关注的问题。     

核电厂核事故应急演习新模式的实践

研究核事故应急演习监督评估的现状及存在问题,探索并首次实践了一种"无预先通知、无演习脚本、无专门准备、多重突发事件叠加"的核事故综合应急演习监督评估模式,分析了这种模式的良好实践,并讨论了后续深入开展相关工作的方法。     

Quantitative assessment of severe accident management strategies in a nuclear power plant

Nuclear power plants in Korea are preparing improvement countermeasures for severe accidents including mobile gas turbine generators, passive autocatalytic recombiners, containment-filtered venting systems, and external injection using portable pumps. However, these improvement countermeasures have only been determined by expert judgment, and detailed validation of their effects has not been performed. In this paper, the quantitative safety impact of these improvement countermeasures was evaluated for the Westinghouse 3-loop pressurized water reactor. Our evaluation of four improvement countermeasures using the at-power internal event probabilistic safety assessment models revealed that all containment failure modes have positive effects, except for the containment isolation failure and the containment bypass. Therefore, post-Fukushima action plans for coping with a severe accident in Korea have been appropriately evaluated and established.