共查询到20条相似文献,搜索用时 187 毫秒
1.
对γ辐射剂量率的连续监测是核电厂常规监测和监督性监测的主要内容。分析γ辐射剂量率连续监测数据的影响因素,对于识别核电厂的异常排放、建立应急监测本底具有重要意义。本文以宁德核电厂监督性监测系统2016年一整年的γ辐射剂量率逐时连续监测数据为例,分析各种可能的影响因素,包括宇宙射线响应、气象参数的影响、核电厂的排放等,研究各种因素的影响特征。结果表明,γ辐射主要来自地表中的天然放射性核素及宇宙射线,气象参数的变化是影响γ辐射剂量率变化的主要因素。结合快速傅里叶分析FFT和气象参数相关性分析,表明γ辐射剂量率连续监测数据存在明显的日周期变化。核事故时释放的放射性可能对剂量率监测结果带来明显的影响。 相似文献
2.
3.
EJ/T984—95环境监测用X,γ辐射仪中规定,剂量率监测系统的有效量程应至少为1×10~(-3)Gyh~(-1)~2.5×10~(-4)Gyh~(-1);而GB11683—89应急辐射防护用携带式高量程X,γ和β辐射剂量和剂量率仪中规定,剂量率仪的有效量程为10~(-4)Gyh~(-1)~10Gyh~(-1)。 在核电厂正常和预期事件状态下,厂区周围的环境辐射水平基本上属于自然本底,而在严重事故状态下烟羽区的剂量率可达10Gyh~(-1)。因此,剂量率监测系统应具备高灵敏度和宽量程。为了 相似文献
4.
环境γ剂量率连续监测系统 总被引:2,自引:0,他引:2
介绍了核电站环境γ剂量率连续监测系统,其中包括探测器系统、数据采集器、中央计算机系统和气象观察系统。还介绍了恒温、防湿和防雷电等措施。本系统经三年多长期运行,证实了性能稳定可靠,将是我国核电厂环境γ剂量率连续监测的最新系统。 相似文献
5.
6.
秦山核电厂环境γ剂量率连续监测系统 总被引:2,自引:1,他引:1
本文介绍秦山核电厂环境γ剂量率连续监测系统,该系统由监测器,数据采集器,气象站和中心计算机组成,讨论了区分由核电厂排放引起的剂量率的升高斩方法,其监测灵敏度为3nGy/h。 相似文献
7.
通过对10MW高温气冷堆从装料前到满功率运行期间工艺流、工艺间、流出物、厂区环境的放射性核素含量、个人剂量水平进行的系统监测,了解了反应堆在不同功率下运行时对环境和工作人员的辐射影响,为反应堆安全运行和验收评价提供依据.监测结果显示,除反应堆堆顶距堆芯最近处中子剂量率最高为3.1 μSv/h外,其余点和工艺间均小于2.5 μSv/h(贮留因子T>1/4)的剂量率控制值,厂区环境γ剂量率处于本底水平,烟囱流出物中没有检测到放射性核素(低于方法探测限). 相似文献
8.
9.
1999年~2001年上海市区环境γ辐射剂量率水平监测 总被引:1,自引:0,他引:1
介绍1999年至2001年本所对上海市区环境γ辐射剂量率监测的方法、结果和初步分析。测量结果表明,上海市区环境γ辐射剂量率范围为40-113nGy/h,环境γ辐射剂量率在正常本底水平上波动。 相似文献
10.
为了准确判断降雨对核电厂周围γ辐射监测数据的影响,本文对其进行了量化研究。首先通过雨水中放射性核素测量实验,验证了雨水中影响γ剂量率波动的主要核素为214Pb、214Bi,持续时间约为降雨停止后两个小时。结合相关实测数据和雨水中214Pb、214Bi的衰变规律,进行数值分析与拟合研究,获得降雨对环境γ剂量率影响的数值拟合方程,在多雨峰时,只需要通过第一个雨峰、γ峰的数据,即可拟合预测降雨时刻γ剂量率的变化情况。本文利用不同雨强、不同地域的历史监测数据,对数值拟合方程进行了适用性验证,实测曲线与拟合预测曲线基本一致。这种方法对有多雨峰降雨过程中核电厂周围环境是否存在人工辐射异常进行实时判断具有重要的参考意义。 相似文献
11.
12.
Results of statistical correlation measurements for obtaining information in a complex system are presented. Experiments were performed on four nuclear power plants using conventional plant instrumentation. Inherent fluctuations (noise), response to forced random, sinusoidal and step variations in reactivity were studied. Frequency domain analysis of the data was performed with a special purpose analog type analyzer for determining power and cross-power spectral densities. Results obtained demonstrate that 1) significant semi-quantitative information on the process can be obtained from power spectral analysis on inherent fluctuations: and 2) cross-power spectral techniques permit frequency response measurements and system parameter determination in commercial nuclear plants. 相似文献
13.
为建立基于现场可编程门阵列(FPGA)的反应堆保护系统的可靠性模型,以对系统安全提供有效的分析与验证手段。本研究采用故障树、随机Petri网模型,对CANDU堆1号停堆系统(SDS1)单通道进行可靠性建模与分析。对故障树模型分析得到最小割集,以顶事件发生概率作为系统故障概率,在考虑故障检测、维修与定期试验情况下对随机Petri网模型进行仿真得到系统的拒动概率。研究结果表明,故障树和状态空间方法存在一定局限性,随机Petri网能够反映故障检测与定期试验对反应堆保护系统的影响,可以动态地反映系统可靠性,并且避免了状态空间爆炸问题。因此,本研究建立的随机Petri网模型适用于反应堆保护系统的可靠性建模。 相似文献
14.
在分析M310堆型核电站辐射屏蔽设计中由于工具限制存在的问题以及“华龙一号”堆型核电站辐射屏蔽设计提出的要求的基础上,从程序界面、输入接口、计算功能和辐射场应用扩展4个方面提出先进压水堆核电站辐射屏蔽优化设计对于蒙特卡罗(MC)方法的要求。MC方法在“华龙一号”辐射屏蔽优化设计的应用实践表明,基于MC方法的计算程序在程序界面、输入接口和辐射场应用扩展方面进一步提升之后,可在先进压水堆核电站辐射屏蔽优化设计方面发挥巨大的作用,显著提升核电站辐射屏蔽优化设计的水平。 相似文献
15.
AbstractFor 45 years TN International has been involved in the radioactive materials transportation field. Since the beginning the spent nuclear fuel transportation has been its core business. During all these years TN International, now part of AREVA, has been able to anticipate and fulfil the needs for new transport or storage casks design to fit the nuclear industry evolutions. A whole fleet of casks able to transport all the materials of the nuclear fuel cycle has been developed. This paper focuses on the casks used to transport the fresh and used mix oxide (MOX) fuel. To transport the fresh MOX boiling water reactor and pressurised water reactors fuel, TN International has developed two designs of casks: the MX 6 and the MX 8. These casks are and have been used to transport MOX fuel for French, German, Swiss and in a near future Japanese nuclear power plants. A complete set of baskets have been developed to optimise the loading in terms of integrated dose and also of course capacity. Mixed oxide used fuel has now its dedicated cask: the TN 112 which certificate of approval has been obtained in July 2008. This cask is able to transport 12 MOX spent fuel elements with a short cooling time. The first loading of the cask has been performed in September 2008 in the Electricité de France nuclear power plant of Saint-Laurent-des-Eaux. By its continuous involvement in the nuclear transportation field, TN International has been able to face the many challenges linked to the radioactive materials transportation especially talking of MOX fuel. TN International will also have to face the increasing demand linked to the nuclear renaissance. 相似文献
16.
17.
Antônio Carlos A. Mól Cláudio Márcio N.A. Pereira Victor Gonçalves G. Freitas Carlos Alexandre F. Jorge 《Annals of Nuclear Energy》2011,38(2-3):705-712
This paper reports the most recent development results of a simulation tool for assessment of radiation dose exposition by nuclear plant’s personnel, using artificial intelligence and virtual reality technologies. The main purpose of this tool is to support training of nuclear plants’ personnel, to optimize working tasks for minimisation of received dose. A finer grid of measurement points was considered within the nuclear plant’s room, for different power operating conditions. Further, an intelligent system was developed, based on neural networks, to interpolate dose rate values among measured points. The intelligent dose prediction system is thus able to improve the simulation of dose received by personnel. This work describes the improvements implemented in this simulation tool. 相似文献
18.
The irradiation dose rate in March–May 2011 is evaluated for marine biota in the coastal zone near the destroyed Fukushima
reactor and in the open sea. It is shown that for representative marine organisms (fish and mollusks) the irradiation dose
rate did not exceed the safe level 0.4 mGy/h (10 mGy/day). In the open sea, 30 km from the nuclear power plant, the irradiation
of marine biota is much lower than in the coastal zone near the nuclear power plant. A comparative evaluation is made of the
irradiation dose rate for water organisms in the exclusion zones of the Eastern-Urals track of radioactivity and the Chernobyl
and Fukushima nuclear power plants. 相似文献
19.
海岛核电厂址是目前国内核电厂址选择的重要方向之一。《环境影响评价技术导则 核电厂环境影响报告书的格式和内容》(HJ 808—2016)中明确要求估算核电厂对非人类物种的辐射剂量。本文利用国内某海岛核电厂气态设计排放源项,采用ERICA程序,结合海岛生态本底调查结果,估算了核电厂气载放射性流出物对海岛生物的辐射影响和辐射风险,并进行了海岛生物的“三关键”分析。结果表明,核电厂对海岛各生物的辐射剂量率小于欧盟推荐的筛选值10 μGy/h,总体辐射风险较小。针对ERICA程序中部分参数(如剂量率转换因子和核素转移系数)的适用性问题,提出了今后须重点研究的方向。 相似文献