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1.
高放废物地质处置黏土岩处置库围岩研究现状   总被引:2,自引:0,他引:2  
世界上很多国家都对处置库的可能围岩进行了详细研究。通过对比,认为花岗岩、黏土岩、岩盐比较适合作为处置库围岩,而黏土岩由于具有自封闭性、渗透率低等其他岩石类型不可比拟的优点,因而将黏土岩作为高放废物地质处置库围岩越来越受到各国的关注。文章同时介绍了瑞士、法国、比利时等国家在黏土岩中所进行的大量研究,均认为在黏土岩中处置高放废物和乏燃料是安全的。文章还对黏土岩处置库概念设计、黏土岩处置库围岩地下实验室研究,以及我国开展黏土岩处置库研究的意义等进行了综述。  相似文献   

2.
原型处置库     
论述高放废物地质处置研究中的原型处置库的概念、建造目的和研究的主要内容,以及它在处置库系统性能评价中的作用。原型处置库的研究工作,可以在普通地下实验室中进行(如瑞典的魧sp觟地下实验室),也可以在特定场址地下实验室中进行(如美国尤卡山的ESF坑道),它是以往20多年前地下实验室研究中演示阶段的扩展和延伸,是高放废物地质处置研究中最终确认处置库场址的一个必不可少的研究步骤,同时也为处置库地下工程的详细设计提供最接近于当地建库实际的各类技术参数。  相似文献   

3.
新构造活动强烈程度是高放废物处置库场址评价的一个重要指标。本文阐述新构造研究的指导思想、方法及其在高放废物处置库选址中的应用。通过东天山地区南、北地段对比研究,选出了在新近纪时期构造环境相对稳定或新构造活动强度相对微弱的东天山南部地区,作为高放废物处置库基地。研究结果表明它对场址评价是有意义的。  相似文献   

4.
高放废物处置库甘肃北山预选区地下水位动态特征   总被引:2,自引:0,他引:2  
阐明了甘肃北山预选区地下水位动态特征及其与当地大气降水的关系,并对其动态类型进行了剖析,由此得出北山地区地下水源自当地大气降水补给的认识。为处置库预选区场址评价提供了水文地质依据。  相似文献   

5.
6.
首先以甘肃北山预选区花岗岩场址为例,提出该场址中高放废物地质处置库概念设计和结构设计,然后以系统分析方法论为基础,描述处置库的系统功能、结构、环境及其演化过程,并以模拟软件GoldSim为工具,建立该处置库演化过程的计算机模型,最后以该计算机模型为模拟实验平台,模拟处置库中辐射毒性时空分布,分析模型中的参数灵敏度,优化设计参数,并预测和评价处置库性能。其研究成果可为合理配置资源和有效协调各研究项目之间关系提供技术支持。  相似文献   

7.
本文介绍了高放废物处置场的基本结构并着重阐述了工程地质方法在高放废物处置场建设中的应用,应用主要包括以下几个方面(1)处置场场区围岩稳定性评价;(2)处置场场区岩体力学性质参数的测量;(3)建立处置场场区工程地质模型。  相似文献   

8.
高放废物处置库甘肃北山预选区水文地质特征研究   总被引:10,自引:0,他引:10  
在高放废物深地质处置中,地下不是核素迁移的重要媒介。因此,水文地质工作是处置库选址中的主要内容之一。本文依据几年来的野外调查及前人的部分资料,阐明了我国高放废物处置库甘肃北山预选区的基本水文地质概况,以及地下水的循环交替条件和化学特征。研究表明,弱含水、低渗透、慢流速是区内主要水文地质特征,蒸发浓缩形成的高矿化是地下水的主要化学面貌。这一认识,为处置库选址提供了重要依据。  相似文献   

9.
在高放废物处置库选址中,场地水文地质条件的认识极为重要,因为任何从处置库释放出来的放射性物质都将通过地下水搬运向人类生存环境或生物圈迁移.甘肃北山地区是我国高放废物处置库的重要预选区之一,位于我国西北甘肃省西北部.为了认识预选区的水文地质条件,从水文地质角度评价其作为高放废物处置库场地的适宜性,在过去的10 a,在该区开展了同位素水文地质调查工作.野外调查和氢、氧稳定同位素分析结果表明,研究区地下水主要源自大气降水补给.浅部地下水主要由现代区内降水补给形成,而深部地下水则可能由地质历史时期降水补给形成;浅部地下水系统具有相对开放性特征,水循环交替能力较强,而深部地下水系统具有相对封闭性特征,水循环交替能力较弱.  相似文献   

10.
Forsmark in Sweden has been proposed as the site of a geological repository for spent high-level nuclear fuel, to be located at a depth of approximately 470 m in fractured crystalline rock. The safety assessment for the repository has required a multi-disciplinary approach to evaluate the impact of hydrogeological and hydrogeochemical conditions close to the repository and in a wider regional context. Assessing the consequences of potential radionuclide releases requires quantitative site-specific information concerning the details of groundwater flow on the scale of individual waste canister locations (1–10 m) as well as details of groundwater flow and composition on the scale of groundwater pathways between the facility and the surface (500 m to 5 km). The purpose of this article is to provide an illustration of multi-scale modeling techniques and the results obtained when combining aspects of local-scale flows in fractures around a potential contaminant source with regional-scale groundwater flow and transport subject to natural evolution of the system. The approach set out is novel, as it incorporates both different scales of model and different levels of detail, combining discrete fracture network and equivalent continuous porous medium representations of fractured bedrock.  相似文献   

11.
高阳 《国外铀金地质》2011,(1):42-44,62
根据高放废物选址的要求,利用MapGIS对东天山地区不同时代岩体的空间位置、分布形态、出露面积,以及岩体与断裂构造、地震和矿床点等的空间关系进行了研究,对海量资料信息进行分析处理,可起到事倍功半的效果。利用MapGIS分析结果,初步筛选出阿奇山1号岩体、雅满苏北岩体作为高放废物地质处置库选址的有利岩体。  相似文献   

12.
This paper presents an international, multiple-code, simulation study of coupled thermal, hydrological, and mechanical (THM) processes and their effect on permeability and fluid flow in fractured rock around heated underground nuclear waste emplacement drifts. Simulations were conducted considering two types of repository settings (1) open emplacement drifts in relatively shallow unsaturated volcanic rock, and (2) backfilled emplacement drifts in deeper saturated crystalline rock. The results showed that for the two assumed repository settings, the dominant mechanism of changes in rock permeability was thermal–mechanically induced closure (reduced aperture) of vertical fractures, caused by thermal stress resulting from repository-wide heating of the rock mass. The magnitude of thermal–mechanically induced changes in permeability was more substantial in the case of an emplacement drift located in a relatively shallow, low-stress environment where the rock is more compliant, allowing more substantial fracture closure during thermal stressing. However, in both of the assumed repository settings in this study, the thermal–mechanically induced changes in permeability caused relatively small changes in the flow field, with most changes occurring in the vicinity of the emplacement drifts.  相似文献   

13.
阿拉善地区地壳稳定性研究   总被引:1,自引:0,他引:1  
阿拉善作为中国西部的一个刚性块体,岩石圈有效弹性厚度为40~50km,地壳稳定。新生代以来,由于受印度板块向欧亚板块俯冲的远程效应影响,阿拉善地块发生构造隆升,块体周缘造山带发生构造活动,但块体内部宗乃山一沙拉扎山地区新生代期间为准平原化地貌,新构造运动不发育。综合分析阿拉善地区地壳稳定性和岩体发育情况,笔者遴选出宗乃山~沙拉扎山侵入岩带作为高放废物处置库备选场址的重点工作区。  相似文献   

14.
Effects on groundwater flow of abandoned engineered structures in relation to a potential geological repository for spent high-level nuclear fuel in fractured crystalline rock at the Forsmark site, Sweden, are studied by means of numerical modeling. The effects are analyzed by means of particle tracking, and transport-related performance measures are calculated. The impacts of abandoned, partially open repository tunnels are studied for two situations with different climate conditions: a “temperate” climate case with present-day boundary conditions, and a generic future “glacial” climate case with an ice sheet covering the repository. Then, the impact of abandoned open boreholes drilled through the repository is studied for present-day climate conditions. It is found that open repository tunnels and open boreholes can act as easy pathways from repository level to the ground surface; hence, they can attract a considerable proportion of particles released in the model at deposition hole positions within the repository. The changed flow field and flow paths cause some changes in the studied performance measures, i.e., increased flux at the deposition holes and decreased transport lengths and flow-related transport resistances. However, these effects are small and the transport resistance values are still high.  相似文献   

15.
论述了现有的地下实验室的分类,对普通地下实验室与特定场址地下实验室的主要特征进行了对比分析,论述了各国地下实验室的研究概况,对特定场址地下实验室的概念进行了讨论。鉴于在现行的地下实验室分类中,对特定场址地下实验室的定义似乎界定过宽,因为有些该类型的地下实验室,缺乏明确的历史定位,最终没有起到特定场址地下实验室应起的作用。笔者建议,只有建在经本国政府批准的最终处置库场址上的地下实验室,才可称作为特定场址地下实验室,如美国的WIPP和ESF以及芬兰的ONKALO。因为只有这类地下实验室,才能真正起到论证处置库场址适宜性和高放废物处置方案可行性的作用。  相似文献   

16.
高放废物处置库选址中低渗透介质地质研究的几个问题   总被引:3,自引:0,他引:3  
低渗透介质是阻碍有害物质在地下迁移良好的天然屏障, 因此成为高放废物处置库围岩类型的首选。本文通过对高放废物处置库选址中地质研究的回顾, 阐述了低渗透介质地质研究的特点, 对地质参数测定、取样、水流模拟、地球化学模拟进行了重点介绍。  相似文献   

17.
Hydrogen gas (H2) may be produced by the anoxic corrosion of steel components in underground structures, such as geological repositories for radioactive waste. In such environments, hydrogen was shown to serve as an electron donor for autotrophic bacteria. High gas overpressures are to be avoided in radioactive waste repositories and, thus, microbial consumption of H2 is generally viewed as beneficial. However, to fully consider this biological process in models of repository evolution over time, it is crucial to determine the in situ rates of microbial hydrogen oxidation and sulfate reduction. These rates were estimated through two distinct in situ experiments, using several measurement and calculation methods. Volumetric consumption rates were calculated to be between 1.13 and 1.93 μmol cm−3 day−1 for H2, and 0.14 and 0.20 μmol cm−3 day−1 for sulfate. Based on the stoichiometry of the reaction, there is an excess of H2 consumed, suggesting that it serves as an electron donor to reduce electron acceptors other than sulfate, and/or that some H2 is lost via diffusion. These rate estimates are critical to evaluate whether biological H2 consumption can negate H2 production in repositories, and to determine whether sulfate reduction can consume sulfate faster than it is replenished by diffusion, which could lead to methanogenic conditions.  相似文献   

18.
高放废物深地质处置:回顾与展望   总被引:10,自引:0,他引:10  
王驹 《铀矿地质》2009,25(2):71-77
文章对我国高放废物地质处置研究的历史进行了回顾,并对未来发展进行了展望。我国的高放废物深地质处置研究开发从1985年开始,迄今为止可初步分为3个阶段:①起步和跟踪研究阶段(1985~1998);②逐步发展阶段(1999~2005);③政府规划指导阶段(2006至今)。20多年来,我国在国家法律法规、战略规划、选址、工程屏障、核素迁移研究等方面取得了显著进展。我国已经提出在2020年前建成地下实验室、21世纪中叶建成高放废物处置库的目标。研究开发和处置库工程建设分成3个阶段:试验室研究开发和处置库选址阶段(2006~2020);地下现场试验阶段(2021-2040)和处置库建设阶段(2041~本世纪中叶)。经过全国筛选对比,已初步选定甘肃北山地区为重点预选区,系统的场址评价工作正在进行。已确定采用膨润土作为处置库的回填材料,并初步确定内蒙古高庙子膨润土为我国高放废物处置库的首选缓冲回填材料。工程设计、核素迁移研究和安全评价也取得了一定进展。1999年起与国际原子能机构开展了3期高放废物地质处置技术合作项目,对提高我国的技术水平起到了积极作用。20多年的研究开发工作为我国在21世纪完成高放废物地质处置任务奠定了基础。  相似文献   

19.
地下水流数值模拟是高放废物处置库选址中水文地质评价的重要内容.水文地质概念模型是地下水流数值模拟的基础和前提.在北山预选区水文地质分析基础上,利用DEM数据生成了研究区地表水系,据此确定了模拟范围;借助GMS软件,建立了研究区三维水文地质结构模型;再通过边界条件、流场特征、地下水均衡项和水文地质参数的分析和描述,建立了北山地区水文地质概念模型.  相似文献   

20.
According to the present concept for final storage of spent nuclear fuel in Sweden, the spent fuel, encapsulated in copper or copper/steel canisters, will be placed in tunnels in a deep rock formation. The canisters will be surrounded by compacted bentonite clay acting as a buffer material. In connection with a safety analysis of such a storage facility, the total solubility of certain elements (e.g., uranium) as well as the transport properties (e.g., retardation due to sorption on mineral surfaces) of the long-lived radionuclides released from the canister have to be predicted or measured. The chemical conditions, governing the solubility and speciation of trace elements encountered in and around the repository depend on interactions between the ground water and the engineering materials in the repository and a production of oxidants due to radiolysis in the spent fuel. In the present study the speciation and solubility of uranium and neptunium in a bentonite-ground water system and in ground waters with compositions measured at a site at äspö, SE Sweden, have been calculated. The calculations have been carried out using a recent version of the geochemical computer code PHREEQE and the database HATCHES 5.0. Predictions of the uranium and neptunium concentrations in the ground water in the vicinity of a damaged high level waste repository have also been performed. The uranium concentration in the water in the bentonite barrier is predicted to be of the same order of magnitude or lower than that found in some granitic ground waters. For neptunium the calculations are uncertain due to the small amount of experimentally determined thermodynamic data and few verifications under the conditions (pH - Eh - carbonate concentration) considered. The predicted concentrations (ca 10–12 m, corresponds to ca 0.006 Bq/l) may be regarded as high, considering the high toxicity of neptunium and its long half-life.  相似文献   

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