Physicochemical Reasons for the Use of TiOHPO4 for Treatment of Liquid Radioactive Waste

Heterogeneous exchange of the proton of hydrated titanyl hydrogen phosphate with Li, Na, K, Rb, and Cs cations in aqueous solutions was studied potentiometrically. The sorption equations were proposed. The concentration and thermodynamic equilibrium constants were calculated. The optimal pH range of the solution providing effective sorption of radioactive cesium on hydrated titanyl hydrogen phosphate was determined. The decrease in the efficiency of radiocesium sorption from liquid waste with a high content of competing nonradioactive alkali metal cations is due to a decrease in the pH of this solution in the course of the sorption. To provide efficient sorption removal of radiocesium, the pH should be maintained in the range 4-7, or the sodium form of the sorbent should be used. The selectivity of radiocesium sorption on TiOHPO₄ in the presence of excess sodium cation was estimated.     

Management of Liquid Radioactive Waste from the Shelter

The results of research and regular monitoring of the outflow of radioactive aerosols, as well as leakages of contaminated water from Shelter rooms, were summarized. Formation of radioactive aerosols and liquid radioactive waste (LRW) inside the Shelter were shown to be interconnected, which should be taken into account when addressing the problem of improving the safety of the Shelter. An efficient and economical process flowsheet was proposed for management of the Shelter LRW involving separation of the LRW flows with high and low content of transuranium elements and organic compounds, treatment of a relatively small LRW flow to remove transuranium elements and organic compounds, and processing of the pretreated waste on standard installations of the Chernobyl NPP.     

Physicochemical Modeling of Solid–Liquid Interfacial Processes

A technique is proposed for representing the composition of crystalline compounds and melts by unified parameters of interatomic interaction, which characterize their structure and properties independent of the number of components, their concentrations, and the assumed character of bonding. The models developed by this technique enable quantitative analysis of the interaction between compounds and melts in the contact zone.     

放射性废液罐液位计故障分析研究与处理

核设施的放射性废液收集与处理系统通常采用吹气式液位计,本文根据一次吹气式液位计的故障,基于其现象及试验进行故障分析,得到压差变送器和吹气系统管路对仪表测量值的具体影响,并通过现场排查确定故障原因,总结吹气式液位计故障分析策略,目的是在液位计故障发生后,可以通过实际现象精准快速地判断故障原因,完成维修,保障核设施正常运行...     

Feasibility of Processing of Accumulated Liquid Radioactive Waste from BN-350 Reactor

It was found that the filtrate yielded by passing bottoms decantates through selective sorbents has the volume activity with respect to ¹³⁷Cs and ⁶⁰Co significantly greater than DK_b. A pretreatment of the bottoms before selective sorption was tested, which consisted in ozonation and subsequent filtration of the resulting precipitate. By the example of the liquid radioactive waste (LRW) decantate with the highest volume activity, it was shown that by combining the pretreatment with selective sorption it was possible to remove ¹³⁷Cs, ⁶⁰Co, and ⁵⁴Mn radionuclides from the decantate to the level under DK_b. Cementation of the slurries in the slurry/cement ratio of 0.3-0.7 was tested. It was proposed that the decantate freed from radionuclides be discharged into the Caspian Sea, and the slurry and secondary wastes yielded by decantate decontamination be included into cement compound.     

Metallurgical Technologies and Problems Related to Self-Disposal of Radioactive Waste by Deep Rock Melting

Radioactive waste arranged inside the container releases heat as a result of radioactive decay. If the heat power is sufficient, the geological rock near the container melts and the container moves into the Earth's depths. This method of self-immersion of radioactive waste may be suggested as an additional method to the deep geological disposal approach. The basic problem of method realization is to find a container material that remains firm in a temperature of about 1300–1400°C in melted rock (for example basalt). This problem is considered in connection with the question of radioactive matrix choice and compatibility of materials.     

珍珠岩粉体对含~(90)Sr放射性废液处理的研究

为研究珍珠岩粉体对含90Sr放射性核废液的吸附性能,利用Sr(NO3)2配置一定浓度的模拟核废液,以不同粒度的珍珠岩粉体为吸附剂,进行珍珠岩对模拟核废液中Sr2+的吸附性能研究。利用X射线荧光光谱仪、扫描电子显微镜和原子吸收光谱对样品中的元素含量、微观形貌及对Sr2+的吸附行为进行表征。结果表明:溶液为中性条件下,珍珠岩粉体对Sr2+的处理是以快速吸附机制进行的;珍珠岩对Sr2+的去除效果与样品的粒度呈一致性关系,粒度在75～100μm范围的珍珠岩对于Sr2+的处理效果最好,5 min时对Sr2+的去除率即可达到89%以上。珍珠岩粉体适合于对含Sr2+中性放射性废液进行快速处理。     

Treatment of Locally Accumulated Liquid Radioactive Waste at the Shelter To Remove Transuranium Elements

Liquid radioactive waste (LRW) from the Shelter yielded by reactions of atmospheric precipitations, condensate, and dust-suppressing solutions with structural materials and fuel-containing masses are alkali-carbonate solutions containing fission products (¹³⁷Cs, ⁹⁰Sr), organic compounds, uranium, and transuranium elements. This waste is unsuitable for treatment by the standard procedure utilized at the Chernobyl NPP, as the content of organic compounds and transuranium elements in the Shelter LRW exceeds that acceptable for evaporators. For pretreatment of the Shelter LRW to remove organic compounds of uranium and transuranium elements, a procedure was developed and tested at the Shelter, based on the use of hydrolysis lignin as sorbent and specially designed equipment.     

Theoretical Analysis and Procedure for the Calculation of Thermophysical Processes Occurring in a Cryogenic Vessel under Conditions of Nonvented Storage

A theoretical analysis is made of the processes which define the rate of pressure rise in a vessel with cryogenic liquid under conditions of nonvented storage. Different methods of the calculation of pressure are treated. The determining part played by thermal stratification in the liquid phase is demonstrated. A new procedure is suggested for the calculation of pressure and thermal stratification in a liquid.     

Behavior of U(VI) under the Conditions of a Reservoir Bed for Liquid Radioactive Waste

The behavior of U(VI) under the conditions of liquid radioactive waste (LRW) disposal in a reservoir bed was studied. Model experiments were performed to determine the radionuclide binding mechanism and the role of hydrolysis products of LRW cations and of sands from the reservoir bed. The U(VI) binding with the reservoir bed rocks depends on pH of the solution. The U(VI) binding with the solid phase under the conditions of LRW reservoir bed is determined by sorption reactions with components of the surrounding rocks. The kinetic of uranium leaching occurring with a decrease in pH of the solution was studied.     

Effect of Contact Time of Liquid Radioactive Waste with Bed Rock of Underground Repository on Migration Behavior of 90Sr, 137Cs, 239Pu,and 241Am

Behavior of radionuclides caused by interaction of acidic waste with sandy bedrock in deep underground repositories is studied, including sorption-desorption of ⁹⁰Sr, ¹³⁷Cs, ²³⁹Pu, and ²⁴¹Am. The amount of mobile forms of radionuclides decreases with increasing contact time with bedrock, thus decreasing the migration rate of the radionuclides in the collector bed.     

填充床潜热储热数值模型研究进展

填充床潜热储热技术广泛应用于太阳能热利用和供热通风与空气调节等领域。由于不同应用环境下的填充床潜热储热系统具有复杂的瞬态特性和较高的实验成本,在研究不同因素对储热系统性能的影响时,研究人员开发了相关数学模型,并采用不同数值计算方法进行分析。对常见的填充床储热过程数值模型进行分类,详细分析不同模型的特点与适用性;对比了模型的计算效率和误差;最后,总结了不同数值模型在潜热型填充床储热技术中的应用特点,可为同类模型的开发与应用提供依据。     

Naturally Occurring Radionuclides of Uranium and Thorium Series in Nonnuclear Industrial Processes

Distribution of naturally occurring radionuclides of the Th and U series in nonnuclear industrial processes is discussed. Some parallelism is found between the migration of naturally occurring radionuclides in the geological environment and their fate in industrial processes. In both cases, the behavior is governed by well-known laws for phase distribution of microcomponents. Differences in the behavior of particular members of the radioactive series in processing of natural raw materials are caused by specific chemical properties of parent and daughter nuclides. It was demonstrated with a number of examples that, in non-nuclear industrial processes, radionuclides can concentrate to a level requiring special protection measures.     

烧绿石固化高放废物的研究进展

自然界中稳定存在的烧绿石由于在高放废物固化研究中呈现出的良好特性,近年来得到了大量的研究.在前人研究成果的基础上,对烧绿石的晶体结构与固化机理、锕系核素和稀土类似物的包容情况以及固化体的合成方法和相关性能等进行了系统的研究总结.已有的研究表明,烧绿石人造岩石固化体具有较高的密度和包容量,良好的抗浸出和抗辐照性能,是固化高放废物和进行最终地质处置的理想固化体,具有良好的应用前景.     

Key Scientific Challenges in Geological Disposal of High Level Radioactive Waste

The geological disposal of high level radioactive waste is a challenging task facing the scientific and technical world. This paper introduces the latest progress of high level radioactive disposal programs in the world,and discusses the following key scientific challenges: (1) precise prediction of the evolution of a repository site;(2) characteristics of deep geological environment;(3) behaviour of deep rock mass,groundwater and engineering material under coupled conditions (intermediate to high temperature,geostress,hydraulic,chemical,biological and radiation process,etc);(4) geochemical behaviour of transuranic radionuclides with low concentration and its migration with groundwater;and (5) safety assessment of disposal system. Several largescale research projects and several hot topics related with highlevel waste disposal are also introduced.     

石灰岩地下矿山中深孔爆破

原石灰岩矿采用地下浅孔房柱法开采,为提高生产效率和改善工作环境,进行了中深孔爆破试验.选用上层浅孔下层中深孔爆破回采方案.给出了单耗、孔距、排距、最小抵抗线、装药结构、堵塞长度等对比试验数据,通过对微差控制、预裂爆破及爆破振动检测优化了各项参数,降低了矿山综合成本.     

Model of Analysis of the Groundwater-Protection Level in Shallow Land Burial of Radioactive Waste

A mathematical model of transfer of radionuclides in the aeration zone has been considered. The analytical solution for this model in a generalized form suitable for practical application has been obtained. A procedure enabling one to determine the optimum size of the protection zone and in which the maximum concentration of radionuclides does not exceed the maximum permissible levels for a specific kind of radionuclides has been proposed. __________ Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 78, No. 4, pp. 180–185, July–August, 2005.     

露天正常台阶深孔爆破处理地下采空区的实践

露天开采中,地下开采形成的采空区已成为矿山安全生产的重大安全隐患.三道庄露天钼矿经过早期多年的地下开采,存在大量的地下空区.通过了解三道庄矿区地下采空区的基本情况,根据现场实际,以1330台阶北部采区内的2处空区为研究对象,按照正常台阶中深孔采矿爆破作业的进度要求,采用逐孔微差起爆一次爆破的方式,成功的以多层一次处理法,在露天爆破的同时对地下空区进行了爆破处理,爆破效果良好.在保证台阶正常生产进度的同时,排除了空区的安全隐患.     

Catalytic Decomposition of Organic Anions in Alkaline Radioactive Waste: 1. EDTA Oxidation

Decomposition of ethylenediaminetetraacetate in alkaline solutions with H₂O₂, Na₂S₂O₈, NaClO, and NaBrO was studied titrimetrically. EDTA is oxidized in solutions heated above 60°C in the presence of cobalt salts at stepwise addition of excess H₂O₂. The reaction between persulfate and EDTA has an induction period decreasing with increasing NaOH concentration and temperature and with decreasing initial EDTA content or with adding AgNO₃, K₄Fe(CN)₆, or NaNO₂. The process involves thermal dissociation of the persulfate ions into radical ions and the subsequent development of a chain reaction. Hypochlorite ions oxidize EDTA in 0.5-5.0 M NaOH at 25-60°C. The process efficiency can be improved by fractional addition of the oxidant in the presence of Co(II) or Ni(II) salts. EDTA is oxidized in alkaline solutions with hypobromite ions only on heating to 95°C. Salts of Co(II), Ni(II), and Cu(II) accelerate the process.