Basic approach to the disposal of low level radioactive waste generated from nuclear reactors containing comparatively high radioactivity

International Nuclear Information System (INIS)

Moriyama, Yoshinori

1998-01-01

Low level radioactive wastes (LLW) generated from nuclear reactors are classified into three categories: LLW containing comparatively high radioactivity; low level radioactive waste; very low level radioactive waste. Spent control rods, part of ion exchange resin and parts of core internals are examples of LLW containing comparatively high radioactivity. The Advisory Committee of Atomic Energy Commission published the report 'Basic Approach to the Disposal of LLW from Nuclear Reactors Containing Comparatively High Radioactivity' in October 1998. The main points of the proposed concept of disposal are as follows: dispose of underground deep enough not be disturb common land use (e.g. 50 to 100 m deep); dispose of underground where radionuclides migrate very slowly; dispose of with artificial engineered barrier which has the same function as the concrete pit; control human activities such as land use of disposal site for a few hundreds years. (author)

Liquid radioactive waste processing system for pressurized water reactor plants

International Nuclear Information System (INIS)

Anon.

1976-01-01

This Standard sets forth design, construction, and performance requirements, with due consideration for operation, of the Liquid Radioactive Waste Processing System for pressurized water reactor plants for design basis inputs. For the purpose of this Standard, the Liquid Radioactive Waste Processing System begins at the interfaces with the reactor coolant pressure boundary and the interface valve(s) in lines from other systems, or at those sumps and floor drains provided for liquid waste with the potential of containing radioactive material; and it terminates at the point of controlled discharge to the environment, at the point of interface with the waste solidification system, and at the point of recycle back to storage for reuse

Analysis of Radioactivity Contamination Level of Kartini Reactor Efluen Gas to the Environment

International Nuclear Information System (INIS)

Suratman; Purwanto; Aminjoyo, S

1996-01-01

The analysis of radioactivity contamination level of Kartini reactor efluen gas to the environment has been done from 13-10-'95 until 8-2-'96. The aim of this research is to determine the radioactivity contamination level on the environment resulted from the release of Kartini reactor efluen gas and other facilities at Yogyakarta Nuclear Research Centre through stack. The analysis methods is the student t-test, the first count factor test and the gamma spectrometry. The gas sampling were carried out in the stack reactor, reactor room, environment and in other room for comparison. Efluen gas was sucked through a filter by a high volume vacuum pump. The filter was counted for beta, gamma and alpha activities. The radioactivity contamination level of the efluen gas passing through the stack to the environment was measured between 0.57 - 1.34 Bq/m3, which was equal to the airborne radioactivity in environment between 0.69 - 1.12 Bq/m3. This radioactivity comes from radon daughter, decay products result from the natural uranium and thorium series of the materials of the building

Radioactive waste management at WWER type reactors

International Nuclear Information System (INIS)

1993-05-01

This report was prepared within the framework of the Technical Assistance Regional Project on Advice on Waste Management at WWER Type Reactors, which was initiated by the IAEA in 1991. The Regional Project is an integral part of the IAEA's activities directed towards improvement of the safety and reliability of nuclear power plants with WWER type reactors (Soviet designed PWRs). Forty-five WWER type units are currently in operation and twenty-five are under construction in Bulgaria, Czechoslovakia, Finland, Hungary and the former USSR. The idea of regional collaboration between eastern European countries under the auspices of the IAEA was discussed for the first time during the last meeting of the Council for Mutual Economic Assistance (CMEA) on spent fuel and radioactive waste management, held in Rez, Czechoslovakia, in October 1990. Since then, the CMEA and some of its former Member States have ceased to exist. However, there are many reasons for eastern European countries to continue their regional collaboration at a higher level. The USSR, the designer and supplier of WWER type reactors in eastern European countries, participated in the first phase of the project. The majority of WWER type reactors are situated in States of the former USSR (Russia and Ukraine). The main results of the first phase of the Regional Project are: (i) Re-establishment of communication channels among eastern European countries operating WWER type reactors by incorporating the IAEA's technical assistance; (ii) Identification of common waste management problems (administrative and technical) requiring resolution; (iii) Familiarization with radioactive waste management systems at nuclear power plants with WWER type reactors - Paks (Hungary), Loviisa (Finland), Jaslovske Bohunice (Czechoslovakia) and Novovoronezh (Russian Federation). Tabs

Study of behaviour of radioactive iodine inorganic compounds in PWR type reactor loops

International Nuclear Information System (INIS)

Alm, M.; Johannsen, K.-H.; Dreyer, R.

1980-01-01

Compounds of radioactive iodine and its distribution between water and vapour depending on temperature, pressure and water regime of reactor coolant with water under pressure are investigated. The field of variation of parameters indicated is widened as compared with operating reactor parameters (pressure 2-14 MPa, temperature 210-335 deg C). Distribution of iodine compounds has been studied by a statistical method. For WWER-type reactors the following conclusions have been drawn: radioactive iodine in water and vapor in the first and second loops exists in the form of iodide, radioactive iodine concentration in water vapour at constant temperature and pressure mainly is depended on water pH value, radioactive iodine solubility in water vapor at normal parameters of the reactor first loop can be approximately calculated by the equation: Ksub(d)=Csub(g)/Csub(l)=(rhosub(g)/rhosub(l))sup(2), where Ksub(d) is a coefficient of solid distribution between water and vapour, rho is density c is concentration [ru

Radioactive waste management practices with KWU-boiling water reactors

International Nuclear Information System (INIS)

Queiser, H.

1976-01-01

A Kraftwerk Union boiling water reactor is used to demonstrate the reactor auxiliary systems which are applied to minimize the radioactive discharge. Based on the most important design criteria the philosophy and function of the various systems for handling the off-gas, ventilation air, waste water and concentrated waste are described. (orig.) [de

Radioactive effluents from CANDU 6 reactors during normal operation

International Nuclear Information System (INIS)

Boss, C.R.; Allsop, P.J.

1995-12-01

During routine operation of a CANDU 6 reactor, various gaseous, liquid, and solid radioactive wastes are generated. The layout of the CANDU 6 reactor and the design of its systems ensure that these are minimized, but small quantities of gaseous and liquid wastes are continually discharged at very low concentrations. This report discusses the make-up of these chronically generated gaseous and liquid effluents. From a safety perspective, the doses to individual members of the public resulting from radioactive wastes chronically discharged from CANDU 6 reactors have been negligible. Similarly, doses to the regional and global populations have been negligible, generally less than 0.001% of background. While far below regulatory limits, releases of tritium, noble gases and gross β - -γ have been the most radiologically significant emissions, while radioiodine and particulates have had the greatest potential to deliver public dose. (author). 8 refs., 16 tabs., 3 figs

Radioactive waste management and disposal scenario for fusion power reactors

Energy Technology Data Exchange (ETDEWEB)

Tabara, Takashi; Yamano, Naoki [Sumitomo Atomic Energy Industries Ltd., Tokyo (Japan); Seki, Yasushi; Aoki, Isao

1997-10-01

The environmental and economic impact of radioactive waste (radwaste) generated from fusion power reactors using five types of structural materials and a light water reactor (LWR) have been evaluated and compared. At first, the amount and the radioactive level of the radwaste generated in five fusion reactors ware evaluated by an activation calculation code. Next, a possible radwaste disposal scenario applicable to fusion radwaste in Japan is considered and the disposal cost evaluated under certain assumptions. The exposure doses are evaluated for the skyshine of gamma-rays during the disposal operation, groundwater migration scenario during the institutional control period of 300 years and future site use scenario after the institutional period. The radwaste generated from a typical LWR was estimated based on a literature survey and the disposal cost was evaluated using the same assumptions as for the fusion reactors. It is found that the relative cost of disposal is strongly dependent on the cost for interim storage of medium level waste of fusion reactors and the cost of high level waste for the LWR. (author)

Study on radioactive waste management scenarios in regular maintenance of a fusion reactor

International Nuclear Information System (INIS)

Someya, Youji; Tobita, Kenji; Yanagihara, Satoshi

2015-01-01

Low-level radioactive waste is generated in large amounts in the operation of a fusion reactor. For this reason, there are needs for the study of radioactive waste management scenarios, as well as the clarification of the function of waste handling facilities in the design phase. This paper describes the management scenarios with a focus on the radioactive waste generated at the time of scheduled maintenance of a nuclear fusion prototype reactor. Based on the temporal change of the residual heat and dose rate of the blanket and diverter, as the furnace equipment associated with induced radioactivity, management period was determined. At this time, the attenuation rate of dose rate and the like of each device are different. So, if maintenance cycle is established for each device and thus storage area is minimized, the control area can be optimized. Based on the 'principle for minimizing radioactive waste,' the reuse of devices is effective in reducing waste. So, in view of a commercial reactor, research and development is required for the establishment of reuse process under high-dose. Since the commitment to radioactive waste is considered to be an important factor in the future for the social acceptance of nuclear fusion reactor development, comprehensive study including the disposal of waste and the reuse of equipment is important. (A.O.)

Analysis on safeguard approach of radioactive waste at KIJANG research reactor

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Jo; Lee, Sung Ho; Lee, Byung Doo; Kim, In Chul; Kim, Hyun Sook; Jung, Juang [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-12-15

KIJANG Research Reactor (KJRR) will be constructed in Busan in order to provide the self-sufficiency of RI demand including Mo-99, to increase the neutron transmutation doping (NTD) capacity and to develop and validate technologies related to the research reactor. Considering the categorization of nuclear facility such as item counting and bulk facility, HANARO which is another research reactors in Korea is item counting facility because physical/chemical forms of nuclear material are not changes. During the dissolving process, radioactive wastes containing nuclear material are occurred at KJRR. In this paper, the features of the KJRR are described and safeguards approach on the radioactive wastes containing nuclear material occurred at KJRR are reviewed. This paper reviews the safeguards approach on radioactive wastes containing nuclear materials occurred during FM production at KJRR. Most uranium dissolved during FM production process are collected in U filter cakes and very tiny amount of uranium will be remained in the ILLW.

Radioactivity Monitoring System for TRIGA 2000 Reactor Water Tank with On-Line Gamma Spectrometer

International Nuclear Information System (INIS)

Prasetyo Basuki; Sudjatmi KA

2009-01-01

One of the requirements in radiological safety in the operating condition of research reactor are the absence of radionuclide from fission product released to reactor cooling water and environment. Early detection of fission product that released from fuel element can be done by monitoring radioactivity level on primary cooling water.Reactor cooling water can be used as an important indicator in detecting radioactivity level of material fission product, when the leakage occurs. Therefore, it needs to build a monitoring system for measuring radioactivity level of cooling water directly and simple. The idea of this system is counting radioactivity water flow from reactor tank to the marinelli cube that attached to the HPGe detector on gamma spectrometer. Cooling water from tank aimed on plastic pipe to the marinelli cube. Water flows in gravitational driven to the marinelli cube, with volume flow rate 5.1 liters/minute in the inlet and 2.2 liters/minute in output. (author)

The radionuclides of primary coolant in HANARO and the recent activities performed to reduce the radioactivity or reactor pool water

Energy Technology Data Exchange (ETDEWEB)

Kim, Minjin [HANARO Research Reactor Centre, Korea Atomic Energy Research Inst., Taejon (Korea, Republic of)

1998-10-01

In HANARO reactor, there have been activities to identify the principal radionuclides and to quantify them under the normal operation. The purposes of such activities were to establish the measure by which we can reduce the radioactivity of the reactor pool water and detect, in early stage, the abnormal symptoms due to the leakage of radioactive materials from the irradiation sample or the damage of the nuclear fuel, etc. The typical radionuclides produced by the activation of reactor coolant are N{sup 16} and Ar{sup 41}. The radionuclides produced by the activation of the core structural material consist of Na{sup 24}, Mn{sup 56}, and W{sup 187}. Of the various radionuclides, governing the radiation level at the pool surface are Na{sup 24}, Ar{sup 41}, Mn{sup 58}, and W{sup 187}. By establishing the hot water layer system on the pool surface, we expected that the radionuclides such as Ar{sup 41} and Mn{sup 56} whose half-life are relatively short could be removed to a certain extent. Since the content of radioactivity of Na{sup 24} occupies about 60% of the total radioactivity, we assumed that the total radiation level would be greatly reduced if we could decrease the radiation level of Na{sup 24}. However the actual radiation level has not been reduced as much as we expected. Therefore, some experiments have been carried out to find the actual causes afterwards. What we learned through the experiments are that any disturbance in reactor pool water layer causes increase of the pool surface radiation level and even if we maintain the hot water layer well, reactor shutdown will be very much likely to happen once the hot water layer is disturbed. (author)

Radioactivity, radiation protection and monitoring during dismantling of light-water reactors

International Nuclear Information System (INIS)

Hummel, L.; Zech, J.B.

2005-01-01

Based on the radioactivity inventory in the systems and components of light-water reactors observed during operation, the impact of actions during plant emptying after the conclusion of power operation and possible subsequent long-term safe enclosure concerning the composition of the nuclide inventory of the plant to be dismantled will be described. Derived from this will be the effects on radioactivity monitoring in the plant, physical radiation protection monitoring, and the measured characterization of the residual materials resulting from the dismantling. The impact of long-term interim storage will also be addressed in the discussion. The talk should provide an overview of the interrelationships between source terms, decay times and the radioactivity monitoring requirements of the various dismantling concepts for commercial light-water reactors. (orig.)

10 CFR 72.108 - Spent fuel, high-level radioactive waste, or reactor-related greater than Class C waste...

Science.gov (United States)

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Spent fuel, high-level radioactive waste, or reactor... RADIOACTIVE WASTE, AND REACTOR-RELATED GREATER THAN CLASS C WASTE Siting Evaluation Factors § 72.108 Spent fuel, high-level radioactive waste, or reactor-related greater than Class C waste transportation. The...

Characterization, treatment and conditioning of radioactive graphite from decommissioning of nuclear reactors

International Nuclear Information System (INIS)

2006-09-01

Graphite has been used as a moderator and reflector of neutrons in more than 100 nuclear power plants and in many research and plutonium-production reactors. It is used primarily as a neutron reflector or neutron moderator, although graphite is also used for other features of reactor cores, such as fuel sleeves. Many of the graphite-moderated reactors are now quite old, with some already shutdown. Therefore radioactive graphite dismantling and the management of radioactive graphite waste are becoming an increasingly important issue for a number of IAEA Member States. Worldwide, there are more than 230 000 tonnes of radioactive graphite which will eventually need to be managed as radioactive waste. Proper management of radioactive graphite waste requires complex planning and the implementation of several interrelated operations. There are two basic options for graphite waste management: (1) packaging of non-conditioned graphite waste with subsequent direct disposal of the waste packages, and (2) conditioning of graphite waste (principally either by incineration or calcination) with separate disposal of any waste products produced, such as incinerator ash. In both cases, the specific properties of graphite - such as Wigner energy, graphite dust explosibility, and radioactive gases released from waste graphite - have a potential impact on the safety of radioactive graphite waste management and need to be carefully considered. Radioactive graphite waste management is not specifically addressed in IAEA publications. Only general and limited information is available in publications dealing with decommissioning of nuclear reactors. This report provides a comprehensive discussion of radioactive graphite waste characterization, handling, conditioning and disposal throughout the operating and decommissioning life cycle. The first draft report was prepared at a meeting on 23-27 February 1998. A technical meeting (TM) was held in October 1999 in coincidence with the Seminar on

Management of radioactive wastes at power reactor sites in India

International Nuclear Information System (INIS)

Amalraj, R.V.; Balu, K.

Indian nuclear power programme, at the present stage, is based on natural uranium fuelled heavy water moderated CANDU type reactors except for the first nuclear power station consisting of two units of enriched uranium fuelled, light water moderated, BWR type of reactors. Some of the salient aspects of radioactive waste management at power reactor sites in India are discussed. Brief reviews are presented on treatment of wastes, their disposal and environmental aspects. Indian experience in power reactor waste management is also summarised identifying some of the areas needing further work. (auth.)

The environmental impact of radioactive releases from accidents in nuclear power reactors

International Nuclear Information System (INIS)

Beattie, J.R.; Griffiths, R.F.; Kaiser, G.D.; Kinchin, G.H.

1978-01-01

A survey of accidental releases of radioactivity from thermal and fast reactors is presented. Following a general discussion on the hazards involved, the nature of the environmental impact of radioactive releases is examined. This includes a brief review of the natural radiation background, the effect on human health of various levels of radiation and radioactivity, permissible and reference levels, and the type of hazards from both passing clouds of airbourne radioactive material and from ground deposited material. The problem of atmospheric dispersion and methods of calculations of radioactive materials in the atmosphere are examined in order for the consequences of accidental release to be analysed. National accidents and their environmental consequences are then examined. Finally there is a review of the risks to which man is always exposed because of his environment. Common and collective risks are also considered. Conclusions are reached as to the acceptibility or otherwise of the environmental impact of reactor accidents. (U.K.)

Release of radioactive fission products from BN-600 reactor untight fuel elements

International Nuclear Information System (INIS)

Osipov, S.L.; Tsikunov, A.G.; Lisitsin, E.C.

1996-01-01

The experimental data on the release of radioactive fission products from BN-600 reactor untight fuel elements are given in the report. Various groups of radionuclides: inert gases Xe, Kr, volatile Cs, J, non-volatile Nb, and La are considered. The results of calculation-experimental study of transfer and distribution of radionuclides in the reactor primary circuit, gas system and sodium coolant are considered. It is shown that some complex radioactivity transfer processes can be described by simple mathematical models. (author)

Experience of work with radioactive materials and nuclear fuel at the reactor WWR-K

International Nuclear Information System (INIS)

Maltseva, R.M.; Petukhov, V.K.

1998-01-01

In the report there are considered questions concerning the handling with fresh and spent fuel, experimental devices, containing high enriched uranium, being fissile materials of the bulk form, radioisotopes, obtained in the reactor, and radioactive waste, formed during the operation of the reactor, and organization of storage, account and control of radioactive and fissile materials is described. (author)

Radiation protection at the RA nuclear reactor in 1987, Part II.a. Control of radioactivity in the environment of the RA nuclear reactor (precipitation, fallout, water, soil, plants, fruit)

International Nuclear Information System (INIS)

Martic, M.; Ajdacic, N.; Jovanovic, J.

1987-01-01

Control of radioactivity in the biosphere in the vicinity of the RA reactor is part of the radioactivity control done regularly for the whole territory of the Vinca Institute. According to the measurements during 1987 it was found that the total contamination of the precipitation was highest in January compared to the period before Chernobylsk accident. Mean monthly value of the total beta cavity was highest in April 5.41 times higher than the relevant value in 1986. This is a preliminary report, the measurement data will be presented after after analysis in the annual report [sr

The regulation on commercial reactors and the management of high-level radioactive wastes in U.S

International Nuclear Information System (INIS)

Shimomura, Hidetsugu

2013-01-01

This article shows U.S. NRC's substantial and procedural regulations regarding commercial reactors and radioactive wastes. The commercial reactor's regulations are analyzed from an ensuring safety, and the radioactive waste' management is done from a locating a disposal site. (author)

Residual radioactivity guidelines for the heavy water components test reactor at the Savannah River Site

International Nuclear Information System (INIS)

Owen, M.B. Smith, R.; McNeil, J.

1997-04-01

Guidelines were developed for acceptable levels of residual radioactivity in the Heavy Water Components Test Reactor (HWCTR) facility at the conclusion of its decommissioning. Using source terms developed from data generated in a detailed characterization study, the RESRAD and RASRAD-BUILD computer codes were used to calculate derived concentration guideline levels (DCGLs) for the radionuclides that will remain in the facility. The calculated DCGLs, when compared to existing concentrations of radionuclides measured during a 1996 characterization program, indicate that no decontamination of concrete surfaces will be necessary. Also, based on the results of the calculations, activated concrete in the reactor biological shield does not have to be removed, and imbedded radioactive piping in the facility can remain in place. Viewed in another way, the results of the calculations showed that the present inventory of residual radioactivity in the facility (not including that associated with the reactor vessel and steam generators) would produce less than one millirem per year above background to a hypothetical individual on the property. The residual radioactivity is estimated to be approximately 0.04 percent of the total inventory in the facility as of March, 1997. According to the results, the only radionuclides that would produce greater than 0.0.1-millirem per year are Am-241 (0.013 mrem/yr at 300 years), C-14 (0.022 mrem/yr at 1000 years) and U-238 (0.034 mrem/yr at 6000 years). Human exposure would occur only through the groundwater pathways, that is, from water drawn from, a well on the property. The maximum exposure would be approximately one percent of the 4 millirem per year ground water exposure limit established by the U.S. Environmental Protection Agency. 11 refs., 13 figs., 15 tabs

Characterization of radioactive graphite and concrete of the reactor ULYSSE/INSTN at CEA/Saclay to be dismantled

International Nuclear Information System (INIS)

Van Lauwe, Aymeric; Ridikas, Danas; Damoy, Francois; Blideanu, Valentin; Fajardo, Christophe; Aubert, Marie-Cecile; Foulon, Francois

2006-01-01

Decommissioning and dismantling of nuclear installations after their service life are connected with the necessity of the disassembling, handling and disposing of a large amount of radioactive material. In order to optimize the disassembling operations, to reduce the undesirable volume to the minimum and to successfully plan the dismantling and disposal of radioactive materials to storage facilities, the radiological characterisation of the material present in the reactor and around its environment should be accurately evaluated. The present work has been done in the framework of the decommissioning and dismantling of the experimental reactor ULYSSE that is presently operating in INSTN/Saclay and will be closed in the middle of 2006. A methodology, already successfully used for another research reactor, is proposed for determining accurately the long-term induced activity of the materials present in the active reactor core and its surroundings. The comparison of theoretical predictions, based on Monte Carlo technique, with experimental values validated the approach and the methodology used in the present study. The goal is to plan efficiently the disassembling and dismantling of the system and to optimise the mass flow going to different waste repositories. We show that this approach might reduce substantially the total cost of decommissioning. (authors)

Verification of using SABINE-3.1 code for calculations of radioactive inventory in reactor shield

International Nuclear Information System (INIS)

Moukhamadeev, R.; Suvorov, A.

2000-01-01

This report presents the results of calculations of radioactive inventory and doses of activation radiation for the International Benchmark Calculations of Radioactive Inventory for Fission Reactor Decommissioning, IAEA, and measurements of activation doses in shield of WWER-440 (Armenian NPP), using one-dimension modified code SABINE-3.1. For decommissioning of NPP it is very important to evaluate in correct manner radioactive inventory in reactor construction and shield materials. One-dimension code SABINE-3.1 (removing-diffusion method for neutron calculation) was modified to perform calculation of radioactive inventory in reactor shield materials and dose from activation photons behind them. These calculations are carried out on the base of nuclear constant system ABBN-78 and new library of activation data for a number of long-lived isotopes, prepared by authors on the base of [9], which present at shield materials as microimpurities and manage radiation situation under the decay more than 1 year. (Authors)

Process for dissolving the radioactive corrosion products from internal surfaces in nuclear reactors

International Nuclear Information System (INIS)

Brown, W.W.

1976-01-01

This invention concerns a process for dissolving in the coolant flowing in a reactor the radioactive substances from the corrosion of the internal surfaces of the reactor to which they cling. When a reactor is operating, the fission occurring in the fuel generates gases and fission substances, such as iodine 131 and 133, cesium 134 and 137, molybdenum 99, xenon 133 and activates the structural materials of the reactor such as nickel by giving off cobalt 58 and similar substances. Under this invention an oxygen rich solution is injected in the reactor coolant after the temperature and pressure reduction stage, during the preparation prior to refuelling and repairs. The oxygen in the solution speeds up the release of cobalt 58 and other radioactive substances from the internal surfaces of the reactor and their dissolving in the oxygenated cold coolant at the start of the cooling procedures of the installation. This allows them to be removed by an ion exchanger before the reactor is emptied. By utilising this process, about half a day may be gained in refuelling time when this has to be done once a week [fr

Alloy development for fast induced radioactivity decay for fusion reactor applications

International Nuclear Information System (INIS)

Klueh, R.L.; Bloom, E.E.

1984-01-01

During the operation of a fusion reactor, the structural material of the first wall and blanket structure will become highly radioactive from activation by the high-energy fusion neutrons. A difficult radioactive waste management problem will be involved in the disposal of this material after the service lifetime is complete. One way to minimize the management problem is the use of structural materials where the radioactive isotopes in the irradiated material decay to levels that allow for simplified disposal techniques. We are exploring how ferritic and austenitic steels could be developed to meet this objective

The possible transmutation of radioactive waste from nuclear reactors

International Nuclear Information System (INIS)

Harries, J.R.

1974-01-01

A nuclear reactor power program produces high level and long lived radioactive wastes. The high level activity is associated with fission products, but beyond 400 years the principal waste hazard is from transuranic elements produced in the reactor. Several schemes have been proposed for the transmutation of the problem isotopes into more easily handled isotopes. The neutron flux in a thermal reactor is not high enough to significantly reduce the longer lived fission product isotopes 90 Sr and 132 Gs, but the transuranic elements can be reduced by recycling through power reactors. The limitation on recycling of the transuranic elements is the separation process to remove trace quantities from the waste stream. In fast reactors the transuranic elements are the principal fuel and fast reactor waste contains only half as much 90 Sr as thermal reactors. However, the overall waste hazard is similar to thermal reactors. A sufficiently intense neutron flux for fission product transmutation could perhaps be produced by a spallation reactor driven by a proton linear accelerator or a controlled thermonuclear reactor. However, both concepts are still some years in the future. Transmutation by accelerator sources of protons, electrons of gammas tend to require more energy than neutron transmutation. (author)

Evaluation of radiological impacts for environmental radioactivity distribution in the Kartini reactor area

International Nuclear Information System (INIS)

Yazid, M.; Suratman; Sutresna, G.; Aminjoyo, S.

1996-01-01

This evaluation covered of gross radioactivity. K-40 radioactivity in the water, soil and grass samples. The measurement of Cs-137 and Sr-90 radioactivity in the water samples have also been done. The aim of this research was determined of radiological impacts in the environment around the Kartini reactor. The water, soil and plant samples were counted of gross beta, Sr-90 activity by beta counter and for K-40, Cs-137 activity by low background gamma spectrometer. For this evaluation can be concluded there are no indication of the radioactivity release from the Kartini reactor operation. Gross beta radioactivity in the water, soil and grass sample are between 0.06-0.61 Bq/l, 0.24-0.79 Bq/g and 3.47-5.70 Bq/g ash. Radioactivity of K-40 in the water, soil and grass sample are between 0.09-0.56 Bq/l, 0.12-0.59 Bq/g and 0.29-0.93 Bq/g ash. The radioactivity of Cs-137 in the water samples are between under limit detectable level to 88.62 mBq/l and Sr-90 are between under limit detectable level to 24.22 mBq/l. (author)

Reduction of releases of radioactive effluents from light-water-power-reactors in Japan

International Nuclear Information System (INIS)

Yoshida, Y.; Itakura, T.; Kanai, T.

1977-01-01

Japan Atomic Energy Commission established the dose objectives to the population around the light-water-reactors in May, 1975, based on the ''ALAP'' concept. These values are respectively, 5 mrems per year for total body and 15 mrems per year for thyroid of an individual in the critical group in the environs, due to both gaseous and liquid effluents from LWRs in one site. The present paper describes the implications of the dose objective values, control measures which have been adopted to reduce releases of radioactive materials and related technical developments in Japan. The main control measures for reduction of radioactive gaseous effluents are an installation of a charcoal gas holdup system for decay of noble gases and a supply of clean steam for the gland seal of a turbine in BWR, and a storage tank system allowing decay of noble gases in PWR. For liquid effluents are taken measures to re-use them as the primary coolant. Consequently, the amounts of radioactivity released to the environment from any LWR during normal operation have been maintained under the level to meet the above dose objective values. For research reactors, reduction of release of effluents has also been carried out in a similar way to LWRs. In order to establish the techniques applicable for further reduction, studies are being made on the control measures to reduce leakage of radioiodine, an apparatus for removal of krypton, the treatment of laundry waste and measures to remove the crud in the primary coolant. Presentation is also made on the energy-integrated gas monitor for gaseous effluent and systems of measuring γ dose from radioactive cloud descriminating from natural background, which have been developed for effective monitoring thus reduced environmental dose

Situation of the radioactive waste management and the employee radiation exposure in commercial power generation reactor facilities in fiscal 1980

International Nuclear Information System (INIS)

1981-01-01

(1) Situation of the radioactive waste management in commercial power generating reactor facilities: The owners of power generation reactor facilities are obligated not to exceed the target dose around the sites by law in the radioactive waste management. The release of radioactive gaseous and liquid wastes and the storage of radioactive solid wastes in respective reactor facilities in fiscal 1980 are presented in tables (for the former, the data since 1971 are also given). The release control values were satisfied in all the facilities. (2) Situation of employe radiation exposure in commercial power generating reactor facilities: The owners of power generation reactor facilities are obligated not to exceed the permissible exposure doses by law. The Employe exposure doses in respective reactor facilities in fiscal 1980 are given in tables. All exposure doses were below the permissible levels. (J.P.N.)

Technical report on natural evaporation system for radioactive liquid waste treatment arising from TRIGA research reactors' decontamination and decommissioning activities

International Nuclear Information System (INIS)

Moon, J. S.; Jung, K. J.; Baek, S. T.; Jung, U. S.; Park, S. K.; Jung, K. H.

1999-01-01

This technical report described that radioactive liquid waste treatment for dismantling/decontamination of TRIGA Mark research reactor in Seoul. That is, we try safety treatment of operation radioactive liquid waste during of operating TRIGA Mark research reactor and dismantling radioactive liquid waste during R and D of research reactor hereafter, and by utilizing of new natural evaporation facility with describing design criteria of new natural evaporation facility. Therefore, this technical report described the quantity of present radioactive liquid waste and dismantling radioactive liquid waste hereafter, analysis the status of radial-rays/radioactivity, and also treatment method of this radioactive liquid waste. Also, we derived the method that the safeguard of outskirts environment and the cost down of radioactive liquid waste treatment by minimize of the radioactive liquid waste quantities, through-out design/operation of new natural evaporation facility for treatment of operation radioactive liquid waste and dismantling radioactive liquid waste. (author). 6 refs., 12 tabs., 5 figs

10 CFR 72.128 - Criteria for spent fuel, high-level radioactive waste, reactor-related greater than Class C waste...

Science.gov (United States)

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Criteria for spent fuel, high-level radioactive waste, reactor-related greater than Class C waste, and other radioactive waste storage and handling. 72.128... STORAGE OF SPENT NUCLEAR FUEL, HIGH-LEVEL RADIOACTIVE WASTE, AND REACTOR-RELATED GREATER THAN CLASS C...

Elementary migration around the Oklo nuclear reactors. Implications for high level radioactive wastes storage

International Nuclear Information System (INIS)

Menet-Dressayre, C.; Menager, M.T.

1993-01-01

The study of Uranium and rare earths near the reactors has displayed the radioelements transfer in the reactors neighbourhood. The main implications for high level radioactive wastes disposal in geological formations are discussed. 12 refs

The behavior of radioactive iodine at the time of reactor accident and its counterplan

International Nuclear Information System (INIS)

Murata, Toshifumi

1974-01-01

When an accident occurs in a reactor, very volatile radioactive iodine is most dangerous among fission products. Among the isotopes of radioactive iodine, 131 I which has longer half-life is harmful. Supposing one-tenth of the radioactivity of 10 8 Ci in a reactor of 10 6 Kw heat output is due to 131 I, it weights about 100g. The behavior of the radioactive iodine is greatly subjected to the influence of inside temperature and other conditions. Therefore, very prudent policies are adopted by installing emergency core cooling system, containment vessels, and activated carbon filters. For the emergency core cooling system, water spraying, flooding with low pressure water, and maintaining of water level by high pressure water injection are adopted, while in the containment vessels, measures are taken so as to lower the inside pressure and minimize leakage. (Kobatake, H.)

General Atomic's radioactive gas recovery system

International Nuclear Information System (INIS)

Mahn, J.A.; Perry, C.A.

1975-01-01

General Atomic Company has developed a Radioactive Gas Recovery System for the HTGR which separates, for purposes of retention, the radioactive components from the non-radioactive reactor plant waste gases. This provides the capability for reducing to an insignificant level the amount of radioactivity released from the gas waste system to the atmosphere--a most significant improvement in reducing total activity release to the environment. (U.S.)

The combined hybrid system: A symbiotic thermal reactor/fast reactor system for power generation and radioactive waste toxicity reduction

International Nuclear Information System (INIS)

Hollaway, W.R.

1991-08-01

If there is to be a next generation of nuclear power in the United States, then the four fundamental obstacles confronting nuclear power technology must be overcome: safety, cost, waste management, and proliferation resistance. The Combined Hybrid System (CHS) is proposed as a possible solution to the problems preventing a vigorous resurgence of nuclear power. The CHS combines Thermal Reactors (for operability, safety, and cost) and Integral Fast Reactors (for waste treatment and actinide burning) in a symbiotic large scale system. The CHS addresses the safety and cost issues through the use of advanced reactor designs, the waste management issue through the use of actinide burning, and the proliferation resistance issue through the use of an integral fuel cycle with co-located components. There are nine major components in the Combined Hybrid System linked by nineteen nuclear material mass flow streams. A computer code, CHASM, is used to analyze the mass flow rates CHS, and the reactor support ratio (the ratio of thermal/fast reactors), IFR of the system. The primary advantages of the CHS are its essentially actinide-free high-level radioactive waste, plus improved reactor safety, uranium utilization, and widening of the option base. The primary disadvantages of the CHS are the large capacity of IFRs required (approximately one MW e IFR capacity for every three MW e Thermal Reactor) and the novel radioactive waste streams produced by the CHS. The capability of the IFR to burn pure transuranic fuel, a primary assumption of this study, has yet to be proven. The Combined Hybrid System represents an attractive option for future nuclear power development; that disposal of the essentially actinide-free radioactive waste produced by the CHS provides an excellent alternative to the disposal of intact actinide-bearing Light Water Reactor spent fuel (reducing the toxicity based lifetime of the waste from roughly 360,000 years to about 510 years)

Radiation protection at the RA Reactor in 1985, Part -2, Annex 1, Radioactivity control of working environment, dosimetry

International Nuclear Information System (INIS)

Ninkovic, M.; Bjelanovic, J.; Minincic, Z.; Komatina, R.; Raicevic, J.

1985-01-01

This report contains data and analysis of the of measured sample results collected during radiation protection control in the working environment of the RA reactor. First part contains basic exposure values and statistical review of the the total number of radiation measurements. It includes contents of radioactive gasses and effluents in the air, as well as the level of surface contamination of clothes and uncovered parts of the personnel bodies. Second part deals with the analysis of personnel doses. It was found that the maximum individual dose from external irradiation amounted to 8.2 mSV during past 10 months. Individual exposures for 7/10 of the personnel were less than 1/10 of the annual permissible exposure. Data are compared to radiation doses for last year and previous five years. Third part of this annex contains basic data about the quantity of collected radioactive waste, total quantity of contaminated and decontaminated surfaces. The last part analyzes accidents occurred at the reactor during 1985. It was found that there have been no accidents that could cause significant contamination of working surfaces and components nor radiation exposure of the personnel [sr

Radiation protection at the RA Reactor in 1986, Part -2, Annex 2a, Radioactivity control of the RA reactor environment (atmospheric precipitations, dust, water, soil, plants, fruit...)

International Nuclear Information System (INIS)

Ajdacic, N.; Martic, M.; Jovanovic, J.

1986-01-01

Control of radioactivity in the biosphere in the vicinity of the RA reactor is part of the radioactivity control done regularly for the whole territory of the Vinca institute (report by the same authors included in this Annex). During 1986 control was conducted according to the plan until May 1, 1986 when a dramatic increase of the precipitations and all other samples from the biosphere was recorded. According to the measured data no significant changes have been found in the surroundings of the RA reactor, until April 29 1986. Since then more detailed control was conducted, the number of samples was increased, apart from standard measuring procedure of total beta activity measurements, gamma spectrometry of all samples was applied. High activity level of the following nuclides was found: Iodine, cerium,cesium, tellurium, ruthenium, barium, lanthanum, etc. As an example activity of ?1?3?1 I in one sample was 564±5 kBq/m 2 [sr

Radioactivity: The town of Marburg after the Chernobyl reactor accident. 2. ed.

International Nuclear Information System (INIS)

Fink, B.

1987-05-01

Strong rainfalls between the 3rd and 5th of May 1986 in the Marburg area brought down the atmospheric radioactivity from the reactor accident. Due to variations in time and intensity, the washout led to different levels of soil radioactivity uptake in the area, so that the eastern part of the Marburg Landkreis accumulated a higher dose than the western part. The additional dose to the thyroid of the adult population in that area, received in the first few days of May, is assessed to be 15 mrem, and about 30 mrem to infants, due to the inhalation of iodine-131, more significant is the dose due to incorporation of radioactivity via the food chain (e.g. Cs-137 and Sr-90), as the radionuclides are accumulated in the body, and part of them will rest there as a lifelong incorporated source of radioactivity. However, there is no acute health hazard to be feared by the population in West Germany, as a result of the reactor accident, but the dose commitment will result in an increase of cancer rate over the next 30 years, which cannot be assessed. (orig./DG) [de

Study and modelling of an innovative coprecipitation reactor for radioactive liquid wastes decontamination

International Nuclear Information System (INIS)

Flouret, Julie

2013-01-01

In order to decontaminate radioactive liquid wastes of low and intermediate levels, the coprecipitation is the process industrially used. The aim of this PhD work is to optimize the continuous process of coprecipitation. To do so, an innovative reactor is designed and modelled: the continuous reactor/classifier. Two model systems are studied: the coprecipitation of strontium by barium sulphate and the sorption of cesium by PPFeNi. The simulated effluent contains sodium nitrate in order to consider the high ionic strength of radioactive liquid wastes. First, each model system is studied on its own, and then a simultaneous treatment is performed. The kinetic laws of nucleation and crystal growth of barium sulphate are determined and incorporated into the coprecipitation model. Kinetic studies and sorption isotherms of cesium by PPFeNi are also performed in order to acquire the necessary data for process modelling. The modelling realised enables accurate prediction of the residual strontium and cesium concentrations according to the process used: it is a valuable tool for the optimization of existing units, but also the design of future units. The continuous reactor/classifier presents many advantages compared to the classical continuous process: the decontamination efficiency of strontium and cesium is highly improved while the volume of sludge generated by the process is reduced. A better liquid/solid separation is observed in the reactor/classifier and the global installation is significantly more compact. Thus, the radioactive liquid wastes treatment processes can be intensified by the continuous reactor/classifier, which represents a very promising technology for future industrial application. (author) [fr

Minimization of radioactive material deposition in water-cooled nuclear reactors

International Nuclear Information System (INIS)

Ruiz, C.P.; Blaies, D.M.

1988-01-01

This patent describes the method for inhibiting the deposition of radioactive cobalt in a water-bearing vessel of a water-cooled nuclear reactor which comprises adding zinc ion to water entering the water-bearing vessel. The improvement contains a substantially lower proportion of the /sup 64/Zn isotope than naturally occurring zinc

Energy-analysis of the total nuclear energy cycle based on light water reactors

International Nuclear Information System (INIS)

Kistemaker, J.

1975-01-01

The energy economy of the total nuclear energy cycle is investigated. Attention is paid to the importance of fossil fuel saving by using nuclear energy. The energy analysis is based on the construction and operation of power plants with an electric output of 1000MWe. Light water moderated reactors with a 2.7 - 3.2% enriched uranium core are considered. Additionally, the whole fuel cycle including ore winning and refining, enrichment and fuel element manufacturing and reprocessing has been taken into account. Neither radioactive waste storage problems nor safety problems related to the nuclear energy cycle and safeguarding have been dealt with, as exhaustive treatments can be found elswhere

Radioactive contamination in the Netherlands caused by the nuclear reactor accident at Chernobyl

International Nuclear Information System (INIS)

1986-10-01

In this report of the Dutch Coordination Commission for Measurements of Radioactivity and Xenobiotic matters (CCRX) a detailed survey is presented of the spread of radioactive material over Europe as a consequence of the reactor accident in Chernobyl and of measurements of the contamination of the physical environment, food and human people in the Netherlands. The radiation burden for the Dutch people and the effects upon public health are estimated and a measuring program is introduced for monitoring the effects of the reactor accident upon the Dutch people. Finally a number of requirements are discussed on the base of the acquired experiments, to which future watching programs should satisfy. 24 refs.; 32 figs.; 16 tabs

Best Available Technique (BAT) as an Instrument for the Limitation of Radioactive Substances from Nuclear Power Reactors in Sweden

International Nuclear Information System (INIS)

Moberg, L.; Sundell-Bergman, S.; Sandwall, J.

2004-01-01

Traditionally, the concept of ALARA has been the basis for limitation and optimisation of releases of radioactive substances from nuclear power reactors in order to protect human health. In recent years, it has been discussed whether the ALARA principle can be applied also to protect the environment. For the protection of the environment, in particular for non-nuclear pollutants, the precautionary principle and the concept of Best Available Technique (BAT) have been applied. New Swedish regulations concerning the protection of human health and the environment from radioactive discharges from certain nuclear installations entered into force January 1st, 2002. The prime purpose of the regulations is to limit the radioactive releases. This limitation shall be based on the optimisation of radiation protection and shall be achieved by using BAT. In order to show compliance with the regulation and BAT, the concepts of reference values and target values have been introduced for nuclear power reactors. The reference value should be the release that is representative for optimum use and full functioning of systems of importance to the occurrence and limitation of radioactive releases from nuclear power reactors. The target value should show the level to which radioactive releases from nuclear power reactors can be reduced during a certain given period of time. Reference and target values have been determined for each nuclear power reactor in Sweden. Each year, the reactor licensees shall report to the Swedish Radiation Protection Authority (SSI) the measures that have been adopted or that are planned to be adopted to limit radioactive releases with the aim of achieving the target values. The first report has been submitted to the SSI in 2003. (Author) 8 refs

Investigation of total α and total β radioactive level of environment mediator in the Dushu lake campus of Suzhou university

International Nuclear Information System (INIS)

Jiang Wenhua; Wan Jun; Liu Li; He Chao; Tang Hua; Tu Yu

2008-01-01

Objective: To get the message of natural radioactive level in the Dushu lake cam- pus of Suzhou university. Methods: Different types of water, soil and food in this region were collected, and then the level of total α and total β radioactivity of the sample was investigated applying model BH1216 equipment which measuring was used for low background total α and β radioactivity. Results: Total α in city water, surface water and soil were 0.061 Bq/L, 0.104 Bq/L, 1708 Bq/kg respectively, total β were 0.183 Bq/L, 0.319 Bq/L, 780 Bq/kg respectively, total α in chive, potato, water bamboo, pork, fish were 1.83, 2.36, 1.84, 3.40, 3.76 Bq/kg respectively, total α of Fish bone was at infra-monitoring lower limit, total β in them were 70.81, 96.71, 60.63, 86.20, 97.51, 73.94 Bq/kg respectively. Conclusion: The results of the investigation display that the total radioactivity in drinking water and food don't exceed limits, in surface water and soil is at normal natural background. It can be concluded that this region has not been polluted by the artificial radioactivity and the environment of human habitation is healthy and safe. (authors)

Individual dose due to radioactivity accidental release from fusion reactor

Energy Technology Data Exchange (ETDEWEB)

Nie, Baojie [Key Laboratory of Neutronics and Radiation Safety, Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui, 230031 (China); University of Science and Technology of China, Hefei, Anhui, 230027 (China); Ni, Muyi, E-mail: muyi.ni@fds.org.cn [Key Laboratory of Neutronics and Radiation Safety, Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui, 230031 (China); Wei, Shiping [Key Laboratory of Neutronics and Radiation Safety, Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Hefei, Anhui, 230031 (China); University of Science and Technology of China, Hefei, Anhui, 230027 (China)

2017-04-05

Highlights: • Conservative early dose of different unit fusion radioactivity release were assessed. • Data of accident level in INES for fusion reactor were proposed. • Method of environmental restoration time after fusion accident was proposed. • The maximum possible accident level for ITER like fusion reactor is 6. • We need 34–52 years to live after the fusion hypothetical accident. - Abstract: As an important index shaping the design of fusion safety system, evaluation of public radiation consequences have risen as a hot topic on the way to develop fusion energy. In this work, the comprehensive public early dose was evaluated due to unit gram tritium (HT/HTO), activated dust, activated corrosion products (ACPs) and activated gases accidental release from ITER like fusion reactor. Meanwhile, considering that we cannot completely eliminate the occurrence likelihood of multi-failure of vacuum vessel and tokamak building, we conservatively evaluated the public radiation consequences and environment restoration after the worst hypothetical accident preliminarily. The comparison results show early dose of different unit radioactivity release under different conditions. After further performing the radiation consequences, we find it possible that the hypothetical accident for ITER like fusion reactor would result in a level 6 accident according to INES, not appear level 7 like Chernobyl or Fukushima accidents. And from the point of environment restoration, we need at least 69 years for case 1 (1 kg HTO and 1000 kg dust release) and 34–52 years for case 2 (1 kg HTO and 10kg–100 kg dust release) to wait the contaminated zone drop below the general public safety limit (1mSv per year) before it is suitable for human habitation.

Radioactive fallout from the Chernobyl nuclear reactor accident

International Nuclear Information System (INIS)

Beiriger, J.M.; Failor, R.A.; Marsh, K.V.; Shaw, G.E.

1987-01-01

Following the accident at the nuclear reactor at Chernobyl, in the Soviet Union on April 26, 1986, we performed a variety of measurements to determine the level of the radioactive fallout on the western United States. We used gamma-spectroscopy to analyze air filters from the areas around Lawrence Livermore National Laboratory (LLNL), California, and Barrow and Fairbanks, Alaska. Milk from California and imported vegetables were also analyzed. The levels of the various fission products detected were far below the maximum permissible concentration levels

Radiation protection at the RA Reactor in 1984, Part -2, Annex 2a: Radioactivity control of the RA reactor environment - atmospheric precipitations, dust, water, soil, plants, fruit.

International Nuclear Information System (INIS)

Ajdacic, N.; Martic, M.; Jovanovic, J.

1984-01-01

Control of radioactivity in the biosphere in the vicinity of the RA reactor is part of the radioactivity control done regularly for the whole territory of the Vinca institute. During 1984 control was conducted according to the plan. According to the measured data no significant changes have been found in the surroundings of the RA reactor. All the analysed samples have followed the activity values of the precipitations

Radioactive inventory in structural materials of ET-R R-1 reactor and its implication on decommissioning.

Energy Technology Data Exchange (ETDEWEB)

Elkady, A; Amin, E [National center for nuclear safety and radiation control, atomic energy authority, Cairo, (Egypt)

1995-10-01

A plan for decommissioning of ET-R R-1 reactor should include estimation of radioactivity in structural materials. The inventory will help in assessing the radiological consequences decommissioning. Conservative calculations have been made to evaluate the activity of the long lived isotopes which can be produced by neutron activation. The materials which are present in significant quantities in the reactor structural materials are aluminium, cast iron, graphite, ordinary and iron shot concrete. The radioactivity of each component is dependent not only upon the major elements, but also on the concentration of the trace elements. The main radioactive inventory are expected to be from Co-60 and Fe-55 which are present in aluminium as trace elements in larger quantities in other construction materials. 2 figs., 4 tabs.

Radioactive effluent sources and special system of channels on the RA Reactor at the Boris Kidric Institute

International Nuclear Information System (INIS)

Bojovic, P.; Gacinovic, O.; Milosevic, M.

1964-10-01

The paper describes the place of origin, composition and activity of radioactive effluents appearing in some reactor systems and special channels for carrying these effluents to disposal basins located outside the reactor building (author)

Evaluating and planning the radioactive waste options for dismantling the Tokamak Fusion Test Reactor

Energy Technology Data Exchange (ETDEWEB)

Rule, K.; Scott, J.; Larson, S. [Princeton Plasma Physics Lab., NJ (United States)] [and others

1995-12-31

The Tokamak Fusion Test Reactor (TFTR) is a one-of-a kind tritium fusion research reactor, and is planned to be decommissioned within the next several years. This is the largest fusion reactor in the world and as a result of deuterium-tritum reactions is tritium contaminated and activated from 14 Mev neutrons. This presents many unusual challenges when dismantling, packaging and disposing its components and ancillary systems. Special containers are being designed to accommodate the vacuum vessel, neutral beams, and tritium delivery and processing systems. A team of experienced professionals performed a detailed field study to evaluate the requirements and appropriate methods for packaging the radioactive materials. This team focused on several current and innovative methods for waste minimization that provides the oppurtunmost cost effective manner to package and dispose of the waste. This study also produces a functional time-phased schedule which conjoins the waste volume, weight, costs and container requirements with the detailed project activity schedule for the entire project scope. This study and project will be the first demonstration of the decommissioning of a tritium fusion test reactor. The radioactive waste disposal aspects of this project are instrumental in demonstrating the viability of a fusion power reactor with regard to its environmental impact and ultimate success.

Scaling factors for the activity determination of radioactive waste from nuclear power reactors

International Nuclear Information System (INIS)

Medici, Marcela A.; Piumetti, Elsa H.

2007-01-01

Specific information of the total activity and activity concentration of the radionuclides contained is required for conditioning, transporting and final disposal of radioactive waste. Due to the complexity associated to alpha and beta measurements for these emitters it is worldwide used, particularly in the case of heterogeneous radioactive waste, the Scaling Factor Method. As in other cases, inputs of the results of the analysis of waste samples taking from waste streams are necessary. The Scaling Factor Method is based on the determination of averaged correlations between the activity concentrations of Difficult to Measure (DTM) nuclides (i.e. alpha and beta emitters) and the activity concentration of easy to measure nuclides (i.e. strong gamma emitters) called Key Nuclides (KN). In the application of this method two phases may be identified: in the first one the degree of correlation between averaged activities of DTM and a given KN is verified, and specific Scaling Factors are derived for every DTM radionuclide. In the second stage the total activity and the activity concentration of the selected KN is determined in each waste item and, by applying the SFs obtained previously, the activities of DTM nuclides are calculated. It is concluded that this method is appropriate and cost-effective and it is stressed that it is only applicable while the Nuclear Power Reactor is in operation. (author)

Current status of radioactive waste management in Japan

International Nuclear Information System (INIS)

Amanuma, Tsuyoshi

1985-01-01

In Japan the nuclear power generation capacity now exceeds the level of 20,000 MW, 24.3 % of the total power generation. It constitutes the major position of energy source, a substitute for a petroleum. In the nuclear power, chemical engineering contributes significantly to treatment and disposal of the radioactive wastes. In the interim report by an ad hoc committee in the Atomic Energy Commission, for the future, rational grouping of the wastes and the direction of land disposal are stated. Contents are the following: basic ideas for the radioactive wastes, radioactive wastes countermeasures in Japan (wastes classification, low and high level and transuranic wastes), radioactive wastes in the nuclear fuel cycle (reactor and fuel reprocessing and reactor dismantling wastes). (Mori, K.)

Actions to reduce radioactive emissions: prevention of containment failure by flooding Containment and Reactor Cavity

International Nuclear Information System (INIS)

Fornos Herrando, J.

2013-01-01

The reactor cavity of Asco and Vandellos II is dry type, thus a severe accident leading to vessel failure might potentially end up resulting in the loss of containment integrity, depending on the viability to cool the molten core. Therefore, significant radioactive emissions could be released to outside. In the framework of Fukushima Stress Tests, ANAV has analyzed the convenience of carrying out different actions to prevent failure of the containment integrity in order to reduce radioactive emissions. The aim of this paper is to present and describe the main phenomenological aspects associated with two of these actions: containment flooding and reactor cavity flooding.

Economics of radioactive material transportation in the light-water reactor nuclear fuel cycle

International Nuclear Information System (INIS)

Dupree, S.A.; O'Malley, L.C.

1980-10-01

This report presents estimates of certain transportation costs, in 1979 dollars, associated with Light-Water Reactor (LWR) once-through and recycle fuel cycles. Shipment of fuel, high-level waste and low-level waste was considered. Costs were estimated for existing or planned transportation systems and for recommended alternate systems, based on the assumption of mature fuel cycles. The annual radioactive material transportation costs required to support a nominal 1000-MW(e) LWR in a once-through cycle in which spent fuel is shipped to terminal storage or disposal were found to be approx. $490,000. Analogous costs for an average reactor operating in a fuel cycle with uranium and plutonim recycle were determined to be approx. $770,000. These results assume that certain recommended design changes will occur in radioactive material shipping systems as a mature fuel cycle evolves

Radioactivity leakage monitoring system

International Nuclear Information System (INIS)

Nakajima, Takuichiro; Noguchi, Noboru.

1982-01-01

Purpose: To obtain a device for detecting the leakage ratio of a primary coolant by utilizing the variation in the radioactivity concentration in a reactor container when the coolant is leaked. Constitution: A measurement signal is produced from a radioactivity measuring instrument, and is continuously input to a malfunction discriminator. The discriminator inputs a measurement signal to a concentration variation discriminator when the malfunction is recognized and simultaneously inputs a measurement starting time from the inputting time to a concentration measuring instrument. On the other hand, reactor water radioactivity concentration data obtained by sampling the primary coolant is input to a concentration variation computing device. A comparator obtains the ratio of the measurement signal from the measuring instrument and the computed data signal from the computing device at the same time and hence the leakage rate, indicates the average leakage rate by averaging the leakage rate signals and also indicates the total leakage amount. (Yoshihara, H.)

Grading of Requirements for Radioactive Waste Activities in Nuclear Research Reactors: Radioisotope Production Facilities

International Nuclear Information System (INIS)

Tawfik, Y.E.

2017-01-01

A graded approach is applicable in all stages of the life time of a research reactor. During the life time of a research reactor, any grading performed should not, in any manner, affect safety functions and operational limits and conditions are preserved, so that there are no undue radiological hazards to workers, public or environment. The grading of activities should be based on safety analyses, and regulatory requirements. Other elements to be considered in grading are the complexity and the maturity of the technology, operating experience associated with the activities and the stage in the life time of the facility. In order to ensure that proper and a de quate provision is made for the safety implications associated with the management and disposal of radioactive waste, the waste is characterized and classified. The general scheme for classifying radioactive waste as presented in the current study is based on considerations of long term safety, and thus, by implication, disposal of the waste. This classification provides a starting point for the grading of activities associated with the packaging and disposal of radioactive waste

Study on treating of low-level radioactive reactor wastewater by combined membrane process (UF-RO)

International Nuclear Information System (INIS)

Lu Yunyun; Cao Qiru; Chen Yunming; Huang Lijuan; Bai Xiaofeng; Li Bing; Feng Liang

2013-01-01

According to the characteristics of radionuclide exists in the low-level radioactive reactor waste water from HFETR, we use a new combined membrane process separation technology to study the efficient treating of low-lever radioactive reactor wastewater. First, the prepared the simulated wastewater contained Cs + , Sr 2+ , CO 2+ , Ni 2+ , and Fe 3+ . Then, we sequentially investigated the pressure, ion concentration, pH value and EDTA, which have effects on the desalination rate of membrane processing metal ions in wastewater. The results show that: in the condition of pH = 7, and added 0.15 mol/L EDTA, the simulated wastewater separated by UF-RO, desalination rates of Cs + , Sr 2+ , CO 2+ , Ni 2+ and Fe 3+ are all above 95%; In the subsequent trials, adding 0.15 mol/L EDTA into the radioactive residuary solution, and then treating by UF-RO-RO, the decontamination efficiency can reach 95.7%. (authors)

Radioactive emission from thermal power plants

Energy Technology Data Exchange (ETDEWEB)

Okamoto, K [New South Wales Univ., Kensington (Australia). Dept. of Applied Mathematics

1981-07-01

Radioactive hazards of the emissions and wastes of thermal power plants arising from fuel impurities of uranium and thorium are discussed. The hazard due to radioactive emission is calculated for an average Australian bituminous coal which contains 2 ppm of U and 2.7 ppm of Th. When the dust removal efficiency of a coal-fired power plant is 99%, the radioactive hazard is greater than that of a nuclear reactor of the same electrical output. After 500 years the radioactive toxicity of the coal waste will be higher than that of fission products of a nuclear reactor and after 2,000 years it will exceed the toxicity of all the nuclear wastes including actinides. The results of a recent calculation are shown, according to which the radioactive hazard of a coal-fired power plant to the public is from several hundred to several tens of thousands of times higher than that of a total fuel cycle of plutonium. It is found that in some regions, such as Japan, the hazard due to /sup 210/Po through seafood could be considerable.

Project requirements for reconstruction of the RA reactor ventilation system, Task 2.8. Measurement of radioactive iodine and other isotopes contents in the gas system of the RA reactor, Annex of the task

International Nuclear Information System (INIS)

Vujisic, Lj. et al

1981-01-01

This report is a supplement to the task 2.8. When planning and constructing the ventilation system, it was found that it is necessary to perform additional experiments during RA reactor operation at 2 MW power level for a longer period. In addition to the helium system, the potential source of radioactive pollutants is the space below the upper water shielding of the reactor. All the experimental and fuel channels are ending in this space. During repair and fuel exchange radioactivity can be released in this space. For that reason this space is important when planing and designing the filtration system for incidental conditions or planned dehermetisation of the reactor. The third point where radioactive isotope identification was done, was the entrance into the chimney during steady state operation and planned dehermetisation of the reactor. The following samples were measured: gas system during reactor operation at 2 MW power; entrance into the chimney during last 48 hours of reactor operation at 2 MW power; sample on the platform under the upper water shield with the opened fuel channel after the reactor shutdown; and simultaneously with the latter, measurement at the entrance to the chimney. This annex contains the list of identified radioactive isotopes, volatile and gaseous as well as concentration of volatile 131 I on the adsorbents [sr

Siting considerations for radioactivity in reactor effluents during normal operation

International Nuclear Information System (INIS)

Graf, J.M.; Strom, P.O.

1975-01-01

In selecting a proper site for a nuclear power station, the consideration of radioactivity released in effluents can be handled in a straightforward manner using the U. S. Atomic Energy Commission's proposed Appendix I to 10 CFR 50, which gives numerical guidelines for design objectives for meeting the criterion ''as low as practicable'' for radioactive material in light-water-cooled nuclear power reactor effluents. By relating the release of radioactive material, the site meteorological conditions, and site boundary distance through appropriate dose models, the suitability of a given site can be determined. ''Rules of thumb'' for comparing anticipated releases to design objectives can be constructed for rapid assessment using the maximum permissible concentration values of 10 CFR 20 as dose factors. These rules of thumb tend to underpredict the allowed releases except in the case of radiocesium in liquids. For gaseous releases, these rules of thumb can be made up in convenient nomogram form for a quick assessment of allowed releases based on local site meteorological conditions. (U.S.)

Calculation of releases of radioactive materials in gaseous and liquid effluents from boiling water reactors (BWR-GALE Code)

International Nuclear Information System (INIS)

Bangart, R.L.; Bell, L.G.; Boegli, J.S.; Burke, W.C.; Lee, J.Y.; Minns, J.L.; Stoddart, P.G.; Weller, R.A.; Collins, J.T.

1978-12-01

The calculational procedures described in the report reflect current NRC staff practice. The methods described will be used in the evaluation of applications for construction permits and operating licenses docketed after January 1, 1979, until this NUREG is revised as a result of additional staff review. The BWR-GALE (Boiling Water Reactor Gaseous and Liquid Effluents) Code is a computerized mathematical model for calculating the release of radioactive material in gaseous and liquid effluents from boiling water reactors (BWRs). The calculations are based on data generated from operating reactors, field tests, laboratory tests, and plant-specific design considerations incorporated to reduce the quantity of radioactive materials that may be released to the environment

Evaluation of Radiological Impacts on the Operating Kartini Reactor and Natural Radioactivity of the Site Plan of Nuclear Power Plant Area

International Nuclear Information System (INIS)

Yazid, M; Sutresna, G; Sulistyono, A; Ngasifudin

1996-01-01

This radiological impacts evaluation covered of radioactivity in water, soil, grass, air samples and ambient gamma radiation that have been carried out in the Kartini reactor area and in the site plan of nuclear power plan are at Ujung Lemah Abang, Jepara, Central Java. The aim of this research was to determine that radiological impacts in the environment around the Kartini reactor compared to natural radioactivity for site plan of nuclear power plan area. The radioactivity in the water, soil and grass samples ware measured by low background beta counting system and were identified by low background gamma spectrometer. The radioactivity in the air samples was measured by beta portable counting system and the ambient gamma radiation was measured by portable high pressurized ionization chamber model RSS-112 Reuther-Stokes. The reactor data measurement was compared to the site plan of nuclear power plant area data for evaluation of radiological impacts on the operating reactor. From the evaluation and comparison can be concluded there are no indication of the radionuclide release from the reactor operation. The average radiactivity in the water, soil grass and air sample from the reactor area were between 0.17 - 0.61 Bq/1; 0,47 - 0,74 Bq/g; 4.43 - 4.60 Bq/g.ash and 49.53 - 70.90 x 10 Bq/cc. The average radioactivity of those sample from the nuclear power plant area were between 0.06-0.90 Bq/I; 0.02-0.86 Bq/g; 1.68-8.07 Bq/g.ash and 65.0-152.3 x 10 Bq/cc. The ambient gamma radiation were between 6.9-36.7 urad/h for the reactor area and 6.8-19.2 urad/h for the nuclear power plant area

(238)U and total radioactivity in drinking waters in Van province, Turkey.

Science.gov (United States)

Selçuk Zorer, Özlem; Dağ, Beşir

2014-06-01

As part of the national survey to evaluate natural radioactivity in the environment, concentration levels of total radioactivity and natural uranium have been analysed in drinking water samples. A survey to study natural radioactivity in drinking waters was carried out in the Van province, East Turkey. Twenty-three samples of drinking water were collected in the Van province and analysed for total α, total β and (238)U activity. The total α and total β activities were counted by using the α/β counter of the multi-detector low background system (PIC MPC-9604), and the (238)U concentrations were determined by inductively coupled plasma-mass spectrometry (Thermo Scientific Element 2). The samples were categorised according to origin: tap, spring or mineral supply. The activity concentrations for total α were found to range from 0.002 to 0.030 Bq L(-1) and for total β from 0.023 to 1.351 Bq L(-1). Uranium concentrations ranging from 0.562 to 14.710 μg L(-1) were observed in drinking waters. Following the World Health Organisation rules, all investigated waters can be used as drinking water.

Utilization of coal fly ash in solidification of liquid radioactive waste from research reactor.

Science.gov (United States)

Osmanlioglu, Ahmet Erdal

2014-05-01

In this study, the potential utilization of fly ash was investigated as an additive in solidification process of radioactive waste sludge from research reactor. Coal formations include various percentages of natural radioactive elements; therefore, coal fly ash includes various levels of radioactivity. For this reason, fly ashes have to be evaluated for potential environmental implications in case of further usage in any construction material. But for use in solidification of radioactive sludge, the radiological effects of fly ash are in the range of radioactive waste management limits. The results show that fly ash has a strong fixing capacity for radioactive isotopes. Specimens with addition of 5-15% fly ash to concrete was observed to be sufficient to achieve the target compressive strength of 20 MPa required for near-surface disposal. An optimum mixture comprising 15% fly ash, 35% cement, and 50% radioactive waste sludge could provide the solidification required for long-term storage and disposal. The codisposal of radioactive fly ash with radioactive sludge by solidification decreases the usage of cement in solidification process. By this method, radioactive fly ash can become a valuable additive instead of industrial waste. This study supports the utilization of fly ash in industry and the solidification of radioactive waste in the nuclear industry.

World ocean and radioactive wastes

International Nuclear Information System (INIS)

Kiknadze, O.E.; Sivintsev, Yu.V.

2000-01-01

The radioecological situation that took shape in the Arctic, North Atlantic Ocean and Far East regions as a result of radioactive waste marine disposal was assessed. Accurate account of radionuclides formation and decay in submerged water-water reactors of nuclear submarines suggests that total activity of radioactive waste disposed near the Novaya Zemlya amounted to 107 kCi by the end of 1999. Activity of radioactive waste disposed in the North Atlantic currently is not in excess of 430 kCi. It is pointed out that the Far East region heads the list in terms of total activity disposed (529 kCi). Effective individual dose for critical groups of population in the Arctic, North Atlantic and Far East regions was determined. The conclusion was made that there is no detrimental effect of the radioactive waste disposed on radioecological situation in the relevant areas [ru

Vietnam Project For Production Of Radioactive Beam Based On ISOL Technique With The Dalat Reactor

International Nuclear Information System (INIS)

Le Hong Khiem; Phan Viet Cuong; Fadi Ibrahim

2011-01-01

The presence in Vietnam of Dalat nuclear reactor dedicated to fundamental studies is a unique opportunity to produce Radioactive Ion (RI) Beams with the fission of a 235 U induced by the thermal neutrons produced by the reactor. We propose to produce RI beams at the Dalat nuclear reactor using ISOL (Isotope Separation On-Line) technique. This project should be a unique opportunity for Vietnamese nuclear physics community to use its own facilities to produce RI beams for studying nuclear physics at an international level. (author)

Modelling of Transport of Radioactive Substances in the Primary Circuit of Water Cooled Reactors

International Nuclear Information System (INIS)

2012-03-01

Since the beginning of the development of water cooled nuclear power reactors, it has been known that the materials in contact with the water release some of their corrosion products into the water. As a consequence, some of the corrosion products are neutron-activated while in the reactor core and then create a gamma radiation field when deposited outside the core. These radiation fields are hazardous to the inspection, maintenance and operating staff in the power plant and therefore must be minimized. Many methods have been developed to control these radiation fields, such as the proper selection of materials and surface finishing technologies at the design stage, operating and shutdown water chemistry optimization, and the application of different decontamination methods. The need to understand the causes of this radioactivity transport has resulted in many mathematical models to describe the transport, irradiation and deposition of the radioactive corrosion products out of the core. Early models were empirical descriptions of the transport, irradiation and deposition steps, and these models allowed analytical solution of the resulting differential equations. As the mechanisms responsible for radioactivity transport gradually became better understood, more precise models of the mechanisms were made. Computer codes to solve the equations describing these models are necessary. Accurate codes are invaluable design tools for carrying out cost-benefit analysis during materials selection, for estimating shielding thicknesses and for evaluating water chemistry specifications, for example. Such codes are also useful in operating plants to predict radiation fields at specific locations where shielding may be required during a maintenance shutdown, for example, when control of radiation dose to staff is essential. To complement the previous work of the International Atomic Energy Agency (IAEA) to improve the mechanistic understanding of radioactivity transport, a

Technical committee meeting on evaluation of radioactive materials release and sodium fires in fast reactors

International Nuclear Information System (INIS)

1996-01-01

The objectives of the Technical Committee Meeting was to review the activities of research on radioactive materials release and sodium fires in fast reactors in each of the participating countries. It covered: out-of-pile experiments and analysis codes on source term; in-pile experiments on source term; core disruptive accidents; sodium leak experience in liquid metal fast reactors; evaluation of sodium fire; and aerosol behaviour

Technical committee meeting on evaluation of radioactive materials release and sodium fires in fast reactors

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-07-01

The objectives of the Technical Committee Meeting was to review the activities of research on radioactive materials release and sodium fires in fast reactors in each of the participating countries. It covered: out-of-pile experiments and analysis codes on source term; in-pile experiments on source term; core disruptive accidents; sodium leak experience in liquid metal fast reactors; evaluation of sodium fire; and aerosol behaviour.

Solid radioactive waste processing system for light water cooled reactor plants

International Nuclear Information System (INIS)

Anon.

1979-01-01

Design, construction and performance requirements are given for the operation of the solid radioactive waste processing system for light water-cooled reactor plants. All radioactive or contaminated materials, including spent air and liquid filter elements, spent bead resins, filter sludge, spent powdered resins, evaporator and reverse osmosis concentrates, and dry radioactive wastes are to be processed in appropriate portions of the system. Sections of the standard cover: overall system requirements; equipment requirement; controls and instrumentation; physical arrangement; system capacity and redundancy; operation and maintenance; and system construction and testing. Provisions contained in this standard are to take precedence over ANS-51.1-1973(N18.2-1973) and its revision, ANS-51.8-1975(N18.2a-1975), Sections 2.2 and 2.3. The product resulting from the solid radioactive waste processing system must meet criteria imposed by standards and regulations for transportation and burial (Title 10, Code of Federal Regulations, Part 71, Title 49, Code of Federal Regulations, Parts 100 to 199). As a special feature, all statements in this standard which are related to nuclear safety are set off in boxes

Mathematical simulation of hazardous ion retention from radioactive waste in fixed bed reactor

International Nuclear Information System (INIS)

Sohsah, M.A.; Gohneim, M.M.; Othman, S.H.; El-Anadouli, B.E.

2007-01-01

Reactor design for fluid-solid, noncatalytic reaction depends on the prediction of the performance of the reactor kinetically. The most mathematical models used to handle fixed bed reactor in which the solid bed constitute one of the reactants, while a second reactant is in the fluid phase are complex and difficult to handle. A new mathematical model which easier to handle has been developed to describe the system under investigation. The model was examined theoretically and experimentally. A column backed with chelating cloth filter to separate radionuclide form radioactive waste solution is used as a practical application for the model. Comparison of the model predictions with the experimental results gives satisfactory agreement at most of the process stages

Management of radioactive waste in nuclear power: handling of irradiated graphite from water-cooled graphite reactors

International Nuclear Information System (INIS)

Anfimov, S.S.

2001-01-01

In this paper an radioactive waste processing of graphite from graphite moderated nuclear reactors at its decommissioning is discussed. Methods of processing of irradiated graphite are presented. It can be concluded that advanced methods for graphite radioactive waste handling are available nowadays. Implementation of these methods will allow to enhance environmental safety of nuclear power that will benefit its progress in the future

Management of radioactive liquid and solid wastes at the Research Reactor Institute, Kyoto University, (3)

International Nuclear Information System (INIS)

Tsutsui, Tenson; Shimoura, K.; Koyama, A.

1977-11-01

In this report, the management of radioactive liquid and solid wastes at the Research Reactor Institute, Kyoto University during past 6 years, from April in 1971 to March in 1977 are reviewed. (auth.)

Radioactive release from VVER-1000 reactors after a terror attack

International Nuclear Information System (INIS)

Sdouz, G.

2005-01-01

Full text: One of the terror scenarios for nuclear power plants is a severe damage of the reactor containment caused by a plane crash or a missile. Due to the loss of electric power the cooling of the core is not maintained leading to a core melt accident. Normally in the course of severe accidents an intact containment has the ability to retain a large part of the radioactive inventory. The goal of this work is the investigation of the behavior of the radioactive release from a VVER-1000-type reactor during a severe accident with a large containment leak from the beginning of the accident. The results are compared with the release in a severe accident via a very small leakage due to the untightness of the containment. This work supplements a series of studies investigating the behavior of a VVER-1000-type reactor during severe accidents under different accident management strategies. The focus in this study is on the 'station blackout'-sequence (or TMLB' in the WASH-1400 nomenclature). The calculations were performed using the Source Term Code Package (STCP), hydrogen explosions are not considered. Up to the melt-through of the cavity bottom the thermal-hydraulics phenomena are almost identical to the TMLB'-case with an intact containment from the beginning. The phenomena occur slightly delayed due to the large containment leak. When the core-concrete-interaction begins the resulting gases leave the containment through the large leak and do not cause a pressure increase. The containment pressure remains at ambient pressure. Due to the different behavior and to the different release times of the nuclides the deviations to the scenario with an intact containment show a great variety. From this comparison it can be shown that the intact containment retains the nuclides up to a factor of 6000. (author)

Method of reducing radioactivity in nuclear reactors

International Nuclear Information System (INIS)

Koshino, Yasuo

1987-01-01

Purpose: To prevent increase of radiation dose ratio in primary coolant circuit pipeways of nuclear reactor and reduce operators' exposure dose upon periodical inspection, etc. Method: β-diketone such as acetylacetone is added in a predetermined amount to reactor cooling water. β-diketone dissolves to catch metal ions and iron oxides as the main ingredient of cruds. The resultant β-diketone complex of metals is slightly water soluble neutron molecule, and the total metal amount in the reactor coolant is at a concentration of less than 10 ppb and completely dissolved in water. Accordingly, deposition of clads in the coolant to pipeways can be prevented thereby enabling to prevent the increase in the radiation dose ratio in the pipeways and thus reduce the operators' exposure dose. (Takahashi, M.)

New treatment centers for radioactive waste from Russian designed VVER-reactors

International Nuclear Information System (INIS)

Chrubasik, A.

1997-01-01

The nuclear power plants using Russian designed VVER-type reactors, were engineered and designed without any wastes treatment facilities. The liquid and solid waste were collected in storage tanks and shelters. After many years of operation, the storage capabilities are exhausted. The treatment of the stored and still generated waste represents a problem of reactor safety and requires a short term solution. NUKEM has been commissioned to design and construct several new treatment centers to remove and process the stored waste. This paper describes the process and lessons learned on the development of this system. The new radioactive waste treatment center (RWTC) includes comprehensive systems to treat both liquid and solid wastes. The process includes: 1) treatment of evaporator concentrates, 2) treatment of ion exchange resins, 3) treatment of solid burnable waste, 4) treatment of liquid burnable waste, 5) treatment of solid decontaminable waste, 6) treatment of solid compactible waste. To treat these waste streams, various separate systems and facilities are needed. Six major facilities are constructed including: 1. A sorting facility with systems for waste segregation. 2. A high-force compactor facility for volume reduction of non-burnable waste. 3. An incinerator facility for destruction of: 1) solid burnable waste, 2) liquid burnable waste, 3) low level radioactive ion exchange resins. 4. A facility for melting of incineration residue. 5. A cementation facility for stabilization of: 1) medium level radioactive ion exchange resins, 2) solid non compactible waste, 3) compacted solid waste. 6. Separation of radionuclides from evaporator concentrates. This presentation will address the facilities, systems, and lessons learned in the development of the new treatment centers. (author)

Simulation of radioactive corrosion product in primary cooling system of Japanese sodium-cooled fast breeder reactor

International Nuclear Information System (INIS)

Matuo, Youichirou; Miyahara, Shinya; Izumi, Yoshinobu

2012-01-01

Radioactive Corrosion Product (CP) is a main cause of personal radiation exposure during maintenance with no breached fuel in fast breeder reactor (FBR) plants. The most important CP is 54 Mn and 60 Co. In order to establish techniques of radiation dose estimation for radiation workers in radiation-controlled areas of the FBR, the PSYCHE (Program SYstem for Corrosion Hazard Evaluation) code was developed. We add the Particle Model to the conventional PSYCHE analytical model. In this paper, we performed calculation of CP transfer in JOYO using an improved calculation code in which the Particle Model was added to the PSYCHE. The C/E (calculated / experimentally observed) value for CP deposition was improved through use of this improved PSYCHE incorporating the Particle Model. Moreover, among the percentage of total radioactive deposition accounted for by CP in particle form, 54 Mn was estimated to constitute approximately 20% and 60 Co approximately 40% in the cold-leg region. These calculation results are consistent with the measured results for the actual cold-leg piping in the JOYO. (author)

Design and implementation of an intensified coprecipitation reactor for the treatment of liquid radioactive wastes

International Nuclear Information System (INIS)

Flouret, Julie; Barre, Yves; Muhr, Herve; Plasari, Edouard

2013-01-01

The coprecipitation is a robust and inexpensive process for the treatment of important volumes of low and intermediate radioactive level liquid wastes. Its major inconvenient is the huge volume of sludge generated. The purpose of this work is to optimize the industrial coprecipitation continuous process by achieving the following objectives: - maximize the decontamination efficiency; - minimize the volume of sludge generated by the process; - reduce the treatment cost decreasing the installation volume. An innovative reactor with an infinite recycling ratio was therefore designed. It is a multifunctional reactor composed of two zones: a perfectly mixed precipitation zone and a classifier to perform liquid-solid separation. The experiments are focused on the coprecipitation of strontium by barium sulphate. The effluent containing sulphate ions and the barium nitrate solution are injected in the reaction zone where strontium and barium co-precipitate as sulphates. The produced solid phase is returned into the reaction zone by the classifier and goes out slowly from the reactor bottom with a residence time much higher than the liquid phase. This creates both a high concentration of solid phase in the reaction zone and a high efficiency of decontamination. The experimental conditions simulate the industrial effluents. The total treatment flow rate is 17 L/h, with an effluent flow rate of 16 L/h and a reactive flow rate of 1 L/h, hence a mean residence time of 10 minutes. In these experimental conditions, the molar ratio sulphate/barium after mixing corresponds to 4.9. These conditions are used in the reprocessing plant of La Hague. The decontamination factor reached in these experimental conditions is excellent: DF = 1500. The decontamination factor obtained with the classical continuous process is only equal to 60. Different process parameters are studied in order to optimize the reactor/classifier: residence time, barium nitrate flow rate and racking flow rate. The

Practical experience for liquid radioactive waste treatment from spent fuel storage pool on RA reactor in Vinca Institute

International Nuclear Information System (INIS)

Plecas, I.; Pavlovic, R.; Pavlovic, S.

2002-01-01

The present paper reports the results of the preliminary removal of sludge from the bottom of the spent fuel storage pool in the RA reactor, mechanical filtration of the pool water and sludge conditioning and storage. Yugoslavia is a country without a nuclear power plant (NPP) on its territory. The law which strictly forbids NPP construction is still valid, but, nevertheless we must handle and dispose radioactive waste. This is not only because of radwaste originating from the use of radioactive materials in medicine and industry, but also because of the waste generated by research in the Nuclear Sciences Institute Vinca. In the last forty years, in the Vinca Institute, as a result of two research reactors being operational, named RA and RB, and as a result of the application of radionuclides in medicine, industry and agriculture, radioactive waste materials of different levels of specific activity were generated. As a temporary solution, radioactive waste materials are stored in two interim storages. Radwaste materials that were immobilized in the inactive matrices are to be placed in concrete containers, for further manipulation and disposal.(author)

Radioactive wastes in Oklo

International Nuclear Information System (INIS)

Balcazar, M.; Flores R, J.H.; Pena, P.; Lopez, A.

2006-01-01

The acceptance of the Nuclear Energy as electric power supply implies to give answer to the population on the two main challenges to conquer in the public opinion: the nuclear accidents and the radioactive wastes. Several of the questions that are made on the radioactive wastes, its are the mobility migration of them, the geologic stability of the place where its are deposited and the possible migration toward the aquifer mantels. Since the half lives of the radioactive waste of a Nuclear Reactor are of several hundred of thousands of years, the technical explanations to the previous questions little convince to the public in general. In this work summary the results of the radioactive waste generated in a natural reactor, denominated Oklo effect that took place in Gabon, Africa, it makes several thousands of millions of years, a lot before the man appeared in the Earth. The identification of at least 17 reactors in Oklo it was carried out thanks to the difference in the concentrations of Uranium 235 and 238 prospective, and to the analysis of the non-mobility of the radioactive waste in the site. It was able by this way to determine that the reactors with sizes of hardly some decimeter and powers of around 100 kilowatts were operating in intermittent and spontaneous form for space of 150,000 years, with operation cycles of around 30 minutes. Recent studies have contributed information valuable on the natural confinement of the radioactive waste of the Oklo reactors in matrixes of minerals of aluminum phosphate that caught and immobilized them for thousands of millions of years. This extracted information from the nature contributes guides and it allows 'to verify' the validity of the current proposals on the immobilization of radioactive wastes of a nuclear reactor. This work presents in clear and accessible form to the public in general on the secure 'design', operation, 'decommissioning' and 'storage' of the radioactive waste of the reactors that the nature put

Behavior of radioactive organic iodide in an atmosphere of High Temperature Gas-cooled Reactor

International Nuclear Information System (INIS)

Saeki, Masakatsu; Nakashima, Mikio; Sagawa, Chiaki; Masaki, Nobuyuki; Hirabayashi, Takakuni; Aratono, Yasuyuki

1990-06-01

Formation and decomposition behavior of radioactive organic iodide have been studied in an atmosphere of High Temperature Gas-cooled Reactor (High Temperature Engineering Test Reactor, HTTR). Na 125 I was chosen for radioactive iodine source instead of CsI diffusing from coated fuel particles. Na 125 I adsorbed on graphite was heated in pure He and He containing O 2 or H 2 O atmosphere. The results obtained are as follows. It was proved that organic iodide was formed with organic radicals released from graphite even in He atmosphere. Thus, the interchange rate of inorganic iodide with organic iodide was remarkably decreased with prolonged preheat-treatment period at 1000degC. Organic iodide formed was easily decomposed by its recirculation into hot reaction tube kept at 900degC. When organic iodide was passed through powdered graphite bed, more than 70% was decomposed at 90degC. Oxygen and water vapour intermixed in He suppressed the interchange rate of inorganic iodide with organic iodide. These results suggest that organic iodide rarely exists in the pressure vessel under normal operating condition of HTTR, and, under hypothetical accident condition of HTTR, organic iodide fraction never exceeds the value used for a safety assessment of light water reactor. (author)

Reactor feedwater device

International Nuclear Information System (INIS)

Igarashi, Noboru.

1986-01-01

Purpose: To suppress soluble radioactive corrosion products in a feedwater device. Method: In a light water cooled nuclear reactor, an iron injection system is connected to feedwater pipeways and the iron concentration in the feedwater or reactor coolant is adjusted between twice and ten times of the nickel concentration. When the nickel/iron ratio in the reactor coolant or feedwater goes nearer to 1/2, iron ions are injected together with iron particles to the reactor coolant to suppress the leaching of stainless steels, decrease the nickel in water and increase the iron concentration. As a result, it is possible to suppress the intrusion of nickel as one of parent nuclide of radioactive nuclides. Further, since the iron particles intruded into the reactor constitute nuclei for capturing the radioactive nuclides to reduce the soluble radioactive corrosion products, the radioactive nuclides deposited uniformly to the inside of the pipeways in each of the coolant circuits can be reduced. (Kawakami, Y.)

Evaluation of environmental impact of radioactive waste from reactor operation

International Nuclear Information System (INIS)

Lombard, J.; Pages, P.

1989-10-01

This paper evaluates the environmental impact of radioactive wastes from reactors operation. We estimate a case of a plant of 20 GWe power operating for 30 years which is equivalent to 600 tons of uranium per year. According to the properties, the waste is stored on surface (Aube site). Starting from the year of storage, we have defined the maximum dose equivalent for an individual from the reference group. The calculation depends on water of outlet water in which some initially stored radionuclides have migrated. Under the most pessimistic estimation, maximum annual dose was of the order of magnitude 0.5 μ Sv (0.05 mrem) for the storage 400 years after opening the site, and after 4000 years. Compared to the values obtained for the radioactive waste storage, the value of this impact is five times higher than the respective surface storage, but two time less than values for underground storage [fr

Plan 96 - Costs for management of the radioactive waste from nuclear power production

International Nuclear Information System (INIS)

1996-06-01

This report presents a calculation of the costs for implementing all measures needed to manage and dispose of spent nuclear fuel and radioactive wastes from the Swedish nuclear power reactors. The cost calculations include costs for R,D and D as well as for decommissioning and dismantling the reactor plants etc. The following facilities and systems are already in operation: Transportation system for radioactive waste products, Central interim storage facility for spent nuclear fuel, Final repository for radioactive operational wastes. Plans exist for: Encapsulation plant for spent nuclear fuel, Deep repository for spent fuel and other long-lived waste, Final repository for decommissioning waste. The total future costs, in Jan 1996 prices, for the Swedish waste system from 1997 have been calculated to be 42.2 billion SEK (about 6.4 billion USD). The total costs apply for the waste obtained from 25 years of operation of all Swedish reactors. It is estimated that 10.6 billion SEK in current money has been spent through 1996. Costs based on waste quantities from operation of the reactors for 40 years are also reported. 6 refs

Evaluation on radioactive waste disposal amount of Kori Unit 1 reactor vessel considering cutting and packaging methods

International Nuclear Information System (INIS)

Choi, Yu Jong; Lee, Seong Cheol; Kim, Chang Lak

2016-01-01

Decommissioning of nuclear power plants has become a big issue in South Korea as some of the nuclear power plants in operation including Kori unit 1 and Wolsung unit 1 are getting old. Recently, Wolsung unit 1 received permission to continue operation while Kori unit 1 will shut down permanently in June 2017. With the consideration of segmentation method and disposal containers, this paper evaluated final disposal amount of radioactive waste generated from decommissioning of the reactor pressure vessel in Kori unit 1 which will be decommissioned as the first in South Korea. The evaluation results indicated that the final disposal amount from the top and bottom heads of the reactor pressure vessel with hemisphere shape decreased as they were cut in smaller more effectively than the cylindrical part of the reactor pressure vessel. It was also investigated that 200 L and 320 L radioactive waste disposal containers used in Kyung-Ju disposal facility had low payload efficiency because of loading weight limitation

Decommissioning the Romanian Water-Cooled Water-Moderated Research Reactor: New Environmental Perspective on the Management of Radioactive Waste

International Nuclear Information System (INIS)

Barariu, G.; Giumanca, R.

2006-01-01

Pre-feasibility and feasibility studies were performed for decommissioning of the water-cooled water-moderated research reactor (WWER) located in Bucharest - Magurele, Romania. Using these studies as a starting point, the preferred safe management strategy for radioactive wastes produced by reactor decommissioning is outlined. The strategy must account for reactor decommissioning, as well as for the rehabilitation of the existing Radioactive Waste Treatment Plant and for the upgrade of the Radioactive Waste Disposal Facility at Baita-Bihor. Furthermore, the final rehabilitation of the laboratories and ecological reconstruction of the grounds need to be provided for, in accordance with national and international regulations. In accordance with IAEA recommendations at the time, the pre-feasibility study proposed three stages of decommissioning. However, since then new ideas have surfaced with regard to decommissioning. Thus, taking into account the current IAEA ideology, the feasibility study proposes that decommissioning of the WWER be done in one stage to an unrestricted clearance level of the reactor building in an Immediate Dismantling option. Different options and the corresponding derived preferred option for waste management are discussed taking into account safety measures, but also considering technical, logistical and economic factors. For this purpose, possible types of waste created during each decommissioning stage are reviewed. An approximate inventory of each type of radioactive waste is presented. The proposed waste management strategy is selected in accordance with the recommended international basic safety standards identified in the previous phase of the project. The existing Radioactive Waste Treatment Plant (RWTP) from the Horia Hulubei Institute for Nuclear Physics and Engineering (IFIN-HH), which has been in service with no significant upgrade since 1974, will need refurbishing due to deterioration, as well as upgrading in order to ensure the

Criteria and measurement techniques applicable to residual radioactivity on a decommissioned reactor site

International Nuclear Information System (INIS)

Woollam, P.B.

1988-12-01

This document summarises the radiological criteria which might be developed to cover the release of a partly decommissioned nuclear reactor site, then looks at the techniques available by which the site could be monitored to assure compliance with these criteria. In particular, the implications of existing levels of radioactive contamination resulting from airburst nuclear weapons tests and the Chernobyl accident are discussed. (author)

Radioactivity. Centenary of radioactivity discovery

International Nuclear Information System (INIS)

Charpak, G.; Tubiana, M.; Bimbot, R.

1997-01-01

This small booklet was edited for the occasion of the exhibitions of the celebration of the centenary of radioactivity discovery which took place in various locations in France from 1996 to 1998. It recalls some basic knowledge concerning radioactivity and its applications: history of discovery, atoms and isotopes, radiations, measurement of ionizing radiations, natural and artificial radioactivity, isotope dating and labelling, radiotherapy, nuclear power and reactors, fission and fusion, nuclear wastes, dosimetry, effects and radioprotection. (J.S.)

A method for prevention of radioactive material release

International Nuclear Information System (INIS)

Uchida, Shunsuke; Sato, Chikara; Kitamura, Masao.

1975-01-01

Object: To provide a method for preventing an underwater radioactive material from being released in a simple and highly reliable manner, which can decrease an amount of radioactive materials discharged into open air from reactor water containing a large amount of radioactive materials such as a reactor core pool. Structure: Pure warm water higher in temperature than that of reactor water is poured from the top of a water surface of a water tank which stores reactor water containing radioactive materials such as radioactive iodine, and water is drawn through an outlet located downwardly of the pure warm water inlet to form a layer of pure warm water at the upper part of the water tank while preventing diffusion of the reactor water into the pure warm water by the difference in density between the reactor water and the pure warm water and downward movement of the pure warm water, thereby preventing contact of the reactor water with the atmosphere and diffusion of the radioactive material into the atmosphere. (Kamimura, M.)

State of exposure control for workers engaging in radiation works and state of radioactive waste management in nuclear reactor facilities for test and research and nuclear reactor facilities at research and development stage, fiscal year 1995

International Nuclear Information System (INIS)

1996-01-01

This is the summary of the reports submitted in fiscal year 1995 by the installers of the nuclear reactor facilities for test and research or at research and development stage, conforming to the related law. The individual dose equivalent of the workers engaging in radiation works in fiscal year 1995 was sufficiently lower than the prescribed limit in all reactor facilities. As for the released quantities of gaseous and liquid wastes, the radioactive substances in the air and water outside the monitor zones never exceeded the prescribed concentration limit in all reactor facilities. In the reactor facilities, for which the target values of release control have been determined, the values were less than the targets in all cases. The increase of stored radioactive solid waste decreased as the dismantling works of the reactor auxiliary system of the nuclear powered ship 'Mutsu' were finished in fiscal year 1994. As the amount of stored radioactive solid waste approaches the installed capacity, the preservation capacity of the existing waste preservation building was increased. (K.I.)

Method to determine the activity concentration and total activity of radioactive waste

International Nuclear Information System (INIS)

Angeles C, A.

2001-02-01

A characteristic system of radioactive waste is described to determine the concentration of radionuclides activity and the total activity of bundles of radioactive waste. The system this integrated by three subsystems: - Elevator of drums. - Electromechanics. - Gamma spectroscopy. In the system it is analyzed waste of issuing gamma specifically, and this designed for materials of relative low density and it analyzes materials of cylindrical recipients

Technology applications for radioactive waste minimization

International Nuclear Information System (INIS)

Devgun, J.S.

1994-01-01

The nuclear power industry has achieved one of the most successful examples of waste minimization. The annual volume of low-level radioactive waste shipped for disposal per reactor has decreased to approximately one-fifth the volume about a decade ago. In addition, the curie content of the total waste shipped for disposal has decreased. This paper will discuss the regulatory drivers and economic factors for waste minimization and describe the application of technologies for achieving waste minimization for low-level radioactive waste with examples from the nuclear power industry

Classification of radioactive wastes produced by the nuclear industry

International Nuclear Information System (INIS)

2013-01-01

This document first indicates the origins of radioactive wastes (mainly electronuclear industry), and the composition of spent fuel, and that only fission products and minor actinides are considered as radioactive wastes whereas uranium and plutonium can be used as new fuel after recycling. The classification of radioactive wastes is indicated in terms of radioactivity level and radionuclide half-life: high level (0.2 per cent of the total waste volume but 96 per cent of total waste radioactivity), medium level long life (3 per cent of volume, 4 per cent of radioactivity), low level long life (7 per cent of volume, 0.1 per cent of radioactivity), low and medium level and short life (63 per cent of volume and 0.02 per cent of radioactivity), very low level (27 per cent of volume and less than 0.01 per cent of radioactivity). An overview of radioactive waste processing and storage in France is presented for each category. Current and predicted volumes are indicated for each category. The main challenges are briefly addressed: spent fuel recycling, waste valorisation by fourth-generation reactors. Processing locations in France and in the World are indicated. Some key figures are provided: 2 kg of radioactive waste are produced per inhabitant and per year, and waste management costs represent 5 per cent of the total cost of produced electricity

Packaging, Transportation, and Disposal Logistics for Large Radioactively Contaminated Reactor Decommissioning Components

International Nuclear Information System (INIS)

Lewis, Mark S.

2008-01-01

The packaging, transportation and disposal of large, retired reactor components from operating or decommissioning nuclear plants pose unique challenges from a technical as well as regulatory compliance standpoint. In addition to the routine considerations associated with any radioactive waste disposition activity, such as characterization, ALARA, and manifesting, the technical challenges for large radioactively contaminated components, such as access, segmentation, removal, packaging, rigging, lifting, mode of transportation, conveyance compatibility, and load securing require significant planning and execution. In addition, the current regulatory framework, domestically in Titles 49 and 10 and internationally in TS-R-1, does not lend itself to the transport of these large radioactively contaminated components, such as reactor vessels, steam generators, reactor pressure vessel heads, and pressurizers, without application for a special permit or arrangement. This paper addresses the methods of overcoming the technical and regulatory challenges. The challenges and disposition decisions do differ during decommissioning versus component replacement during an outage at an operating plant. During decommissioning, there is less concern about critical path for restart and more concern about volume reduction and waste minimization. Segmentation on-site is an available option during decommissioning, since labor and equipment will be readily available and decontamination activities are routine. The reactor building removal path is also of less concern and there are more rigging/lifting options available. Radionuclide assessment is necessary for transportation and disposal characterization. Characterization will dictate the packaging methodology, transportation mode, need for intermediate processing, and the disposal location or availability. Characterization will also assist in determining if the large component can be transported in full compliance with the transportation

One piece reactor removal

International Nuclear Information System (INIS)

Chia, Wei-Min; Wang, Song-Feng

1993-01-01

The strategy of Taiwan Research Reactor Renewal plan is to remove the old reactor block with One Piece Reactor Removal (OPRR) method for installing a new research reactor in original building. In this paper, the engineering design of each transportation works including the work method, the major equipments, the design policy and design criteria is described and discussed. In addition, to ensure the reactor block is safety transported for storage and to guarantee the integrity of reactor base mat is maintained for new reactor, operation safety is drawn special attention, particularly under seismic condition, to warrant safe operation of OPRR. ALARA principle and Below Regulatory Concern (BRC) practice were also incorporated in the planning to minimize the collective dose and the total amount of radioactive wastes. All these activities are introduced in this paper. (J.P.N.)

Nuclear reactor monitoring device

International Nuclear Information System (INIS)

Mihashi, Ishi; Honma, Hitoshi.

1993-01-01

The monitoring device of the present invention comprises a reactor core/reactor system data measuring and controlling device, a radioactivity concentration calculation device for activated coolants for calculating a radioactivity concentration of activated coolants in a main steam and reactor water by using an appropriate physical model, a radioactivity concentration correlation and comparison device for activated coolants for comparing correlationship with a radiation dose and an abnormality alarm device. Since radioactivity of activated primary coolants is monitored at each of positions in the reactor system and occurrence of leakage and the amount thereof from a primary circuit to a secondary circuit is monitored if the reactor has secondary circuit, integrity of the reactor system can be ensured and an abnormality can be detected rapidly. Further, radioactivity concentration of activated primary circuit coolants, represented by 16 N or 15 C, is always monitored at each of positions of PWR primary circuits. When a heat transfer pipe is ruptured in a steam generator, leakage of primary circuit coolants is detected rapidly, as well as the amount of the leakage can be informed. (N.H.)

Transportation risk assessment of radioactive wastes generated by the N-Reactor stabilization program at the Hanford Site, Washington

International Nuclear Information System (INIS)

Wheeler, T.

1994-12-01

The potential radiological and nonradiological risks associated with specific radioactive waste shipping campaigns at the Hanford Site are estimated. The shipping campaigns analyzed are associated with the transportation of wastes from the N-Reactor site at the 200-W Area, both within the Hanford Reservation, for disposal. The analysis is based on waste that would be generated from the N-Reactor stabilization program

Clearance of radioactive materials during reactor dismantling. Permanent enclosure instead of demolition and renaturation?

International Nuclear Information System (INIS)

2016-01-01

During reactor dismantling besides high-level radioactive wastes a large amount of low-level contaminated steel and concrete has to be disposed. In case that radioactivity falls below defined dose limits (10 micro Sv/person and year) these materials may be disposed in domestic waste landfill or in municipal incineration facilities. The issue is discussed in detail including the fact that many power plants are dismantled at the same time so that the contaminated materials might accumulate. Another issue is the occupational safety of contract workers during dismantling. The permanent enclosure could avoid this environmental contamination of decommissioned power plants might also be less expensive.

Evaluation of radioactive inventory of nuclear ship MUTSU

International Nuclear Information System (INIS)

Adachi, M.

1995-01-01

The operation of the Nuclear Ship MUTSU was terminated in January 1992. Radioactivities and dose rates on the surfaces of reactor components were measured in order to estimate the residual radioactive inventory in the MUTSU. The predicted radioactive inventory due to neutron activation was calculated by using a computer code systems. The results show good correlation between predicted and measured values radioactivities in the core baffle plate. The radioactive inventory was estimated to be 8.4 x 10 14 Bq as of 1.5 years from the final shutdown of reactor operation. The contamination in reactor components was estimated from the contamination level measured in the Japan Power Demonstration Reactor (JPDR), from which the dose rates in the reactor room were calculated. The radioactive inventory due to contamination was estimated at 3.4 x 10 10 Bq. Some difference was found between these calculations and measurements. (Author)

Radiation protection at the RA Reactor in 1985, Part -3, Removal and treatment of radioactive effluents for the needs of RA reactor

International Nuclear Information System (INIS)

Plecas, I.; Vukovic, Z.; Kostadinovic, A.

1985-01-01

Contaminated water originates from: hot cells, heavy water distillation device, storage pools for cooling and cutting of fuel elements, water biological shield of the reactor. During 1985 5 m of contaminated water was released from hot cells in the VR-pool containing highly radioactive waste water with 60 Co and trace amount of fission products [sr

Alloy development for fast induced radioactivity decay for fusion reactor applications

International Nuclear Information System (INIS)

Klueh, R.L.; Bloom, E.E.

1984-03-01

The Cr-Mo ferritic (martensitic) steels and austenitic stainless steels (primarily type 316 and variations on that composition) are the leading candidates for the structural components for future fusion reactors. However, irradiation of such steels in a fusion environment produces long-lived radioactive isotopes. These isotopes lead to difficult radioactive waste disposal problems once the structure is removed from service. Such problems could be reduced by developing steels that contain only elements that produce radioactive isotopes that decay to low levels in a reasonable time (tens of years instead of hundreds or thousands of years). This report discusses the development of such steels by making elemental substitutions in the steels now under consideration. Molybdenum must be replaced in the Cr-Mo steels; nickel and molybdenum both must be replaced in the austenitic stainless steels (the nitrogen concentration must be limited, and niobium, maintained to extremely low levels). Appropriate substitutions are tungsten for molybdenum in the Cr-Mo steels and manganese for nickel in the austenitic stainless steels. Indications are that suitable ferritic steels can be developed, but development of a nickel-free austenitic stainless steel with properties similar to the Cr-Ni stainless steels appears to be much more complex

Comparison of planar, PET and well-counter measurements of total tumor radioactivity in a mouse xenograft model.

Science.gov (United States)

Green, Michael V; Seidel, Jurgen; Williams, Mark R; Wong, Karen J; Ton, Anita; Basuli, Falguni; Choyke, Peter L; Jagoda, Elaine M

2017-10-01

Quantitative small animal radionuclide imaging studies are often carried out with the intention of estimating the total radioactivity content of various tissues such as the radioactivity content of mouse xenograft tumors exposed to putative diagnostic or therapeutic agents. We show that for at least one specific application, positron projection imaging (PPI) and PET yield comparable estimates of absolute total tumor activity and that both of these estimates are highly correlated with direct well-counting of these same tumors. These findings further suggest that in this particular application, PPI is a far more efficient data acquisition and processing methodology than PET. Forty-one athymic mice were implanted with PC3 human prostate cancer cells transfected with prostate-specific membrane antigen (PSMA (+)) and one additional animal (for a total of 42) with a control blank vector (PSMA (-)). All animals were injected with [ 18 F] DCFPyl, a ligand for PSMA, and imaged for total tumor radioactivity with PET and PPI. The tumors were then removed, assayed by well counting for total radioactivity and the values between these methods intercompared. PET, PPI and well-counter estimates of total tumor radioactivity were highly correlated (R 2 >0.98) with regression line slopes near unity (0.95radioactivity can be measured with PET or PPI with an accuracy comparable to well counting if certain experimental and pharmacokinetic conditions are met. In this particular application, PPI is significantly more efficient than PET in making these measurements. Copyright © 2017 Elsevier Inc. All rights reserved.

Maintenance of shutdown system in the reactor core to minimize the radioactive waste generation

International Nuclear Information System (INIS)

Ponzoni Filho, P.; Fernandes, V.B.

1988-01-01

This paper recommends a modification on the actual strategy of going from Cold-Shutdown to Critical, that will save about 6000 liter of boric acid and 30,000 liters of demineralized water for each reactor criticalization. This strategy will reduce the radioactive waste disposal volume to only about 5% of what would be generated following the actual strategy. (author) [pt

Total decay heat estimates in a proto-type fast reactor

International Nuclear Information System (INIS)

Sridharan, M.S.

2003-01-01

Full text: In this paper, total decay heat values generated in a proto-type fast reactor are estimated. These values are compared with those of certain fast reactors. Simple analytical fits are also obtained for these values which can serve as a handy and convenient tool in engineering design studies. These decay heat values taken as their ratio to the nominal operating power are, in general, applicable to any typical plutonium based fast reactor and are useful inputs to the design of decay-heat removal systems

Decommissioning of Salaspils Research Reactor

International Nuclear Information System (INIS)

Abramenkovs, A.; Popelis, A.; Abramenkova, G

2008-01-01

The Salaspils Research Reactor (SRR) is out of operation since July 1998 and the decommissioning of SRR was started in 1999 according to the decision of the Government of Latvia. The main decommissioning activities up to 2006 were connected with collecting and conditioning of historical radioactive wastes from different storages outside and inside of reactor hall. The total amount of dismantled materials was about 700 tons, more than 77 tons were conditioned in concrete containers for disposal in repository. The radioactive wastes management technology is discussed in the paper. It was found, that additional efforts must be spent for immobilization of radionuclides in cemented matrix to be comply with the wastes acceptance criteria. The investigations of mechanical stability of water-cement matrix are described and discussed in the paper

Radioactive Wastes Cementation during Decommissioning Of Salaspils Research Reactor

International Nuclear Information System (INIS)

Abramenkova, G.; Klavins, M.; Abramenkovs, A.

2009-01-01

This paper deals with information on the radioactive wastes cementation technology for decommissioning of Salaspils Research Reactor (SRR). Dismantled radioactive materials were cemented in concrete containers using tritiated water-cement mortar. The laboratory tests system was developed to meet the waste acceptance criteria for disposal of containers with cemented radioactive wastes in near-surface repository 'Radons'. The viscosity of water-cement mortar, mechanical tests of solidified mortar's samples, change of temperature of the samples during solidification time and leakage of Cs-137 and T-3 radionuclides was studied for different water-cement compositions with different additives. The pH and electro conductivity of the solutions during leakage tests were controlled. It was shown, that water/cement ratio significantly influences on water-cement mortar's viscosity and solidified samples mechanical stability. Increasing of water ratio from 0.45 up to 0.62 decreases water-cement mortar's viscosity from 1100 mPas up to 90 mPas and decreases mechanical stability of water-cement samples from 23 N/mm 2 to the 12 N/mm 2 . The role of additives - fly ash and Penetron admix in reduction of solidification temperature is discussed. It was found, that addition of fly ash to the cement-water mortar can reduce the solidification temperature from 81 deg. C up to 62 deg. C. The optimal interval of water ratio in cement mortar is discussed. Tritium and Cs-137 leakage tests show, that radionuclides release curves has a complicate structure. The possible radionuclides release mechanisms are discussed. Experimental results indicated that addition of fly ash result in facilitation of tritium and cesium leakage in water phase. Further directions of investigations are drafted. (authors)

Comparison of planar, PET and well-counter measurements of total tumor radioactivity in a mouse xenograft model

International Nuclear Information System (INIS)

Green, Michael V.; Seidel, Jurgen; Williams, Mark R.; Wong, Karen J.; Ton, Anita; Basuli, Falguni; Choyke, Peter L.; Jagoda, Elaine M.

2017-01-01

Introduction: Quantitative small animal radionuclide imaging studies are often carried out with the intention of estimating the total radioactivity content of various tissues such as the radioactivity content of mouse xenograft tumors exposed to putative diagnostic or therapeutic agents. We show that for at least one specific application, positron projection imaging (PPI) and PET yield comparable estimates of absolute total tumor activity and that both of these estimates are highly correlated with direct well-counting of these same tumors. These findings further suggest that in this particular application, PPI is a far more efficient data acquisition and processing methodology than PET. Methods: Forty-one athymic mice were implanted with PC3 human prostate cancer cells transfected with prostate-specific membrane antigen (PSMA (+)) and one additional animal (for a total of 42) with a control blank vector (PSMA (−)). All animals were injected with [ 18 F] DCFPyl, a ligand for PSMA, and imaged for total tumor radioactivity with PET and PPI. The tumors were then removed, assayed by well counting for total radioactivity and the values between these methods intercompared. Results: PET, PPI and well-counter estimates of total tumor radioactivity were highly correlated (R 2 > 0.98) with regression line slopes near unity (0.95 < slope ≤ 1.02) and intercepts near zero (−0.001 MBq ≤ intercept ≤0.004 MBq). Conclusion: Total mouse xenograft tumor radioactivity can be measured with PET or PPI with an accuracy comparable to well counting if certain experimental and pharmacokinetic conditions are met. In this particular application, PPI is significantly more efficient than PET in making these measurements.

Decontamination and radioactivity measurement on building surfaces related to dismantling of Japan power demonstration reactor (JPDR)

International Nuclear Information System (INIS)

Hatakeyama, Mutsuo; Tachibana, Mitsuo; Yanagihara, Satoshi

1997-12-01

In the final stage of dismantling activities for decommissioning a nuclear power plant, building structures have to be demolished to release the site for unrestricted use. Since building structures are generally made from massive reinforced concrete materials, it is not a rational way to treat all concrete materials arising from its demolition as radioactive waste. Segregation of radioactive parts from building structures is therefore indispensable. The rational procedures were studied for demolition of building structures by treating arising waste as non-radioactive materials, based on the concept established by Nuclear Safety Commission, then these were implemented in the following way by the JPDR dismantling demonstration project. Areas of the JPDR facilities are categorized into two groups : possibly contaminated areas, and possibly non-contaminated areas, based on the document of the reactor operation. Radioactivity on the building surfaces was then measured to confirm that the qualitative categorization is reasonable. After that, building surfaces were decontaminated in such a way that the contaminated layers were removed with enough margin to separate radioactive parts from non-radioactive building structures. Thought it might be possible to demolish the building structures by treating arising waste as non-radioactive materials, confirmation survey for radioactivity was conducted to show that there is no artificial radioactive nuclides produced by operation in the facility. This report describes the procedures studied on measurement of radioactivity and decontamination, and the results of its implementation in the JPDR dismantling demonstration project. (author)

Fallout total β radioactivity in every rainfall in Aichi prefecture

International Nuclear Information System (INIS)

Ohnuma, Shoko; Chaya, Kunio; Shimizu, Michihiko; Tomita, Ban-ichi; Hamamura, Norikatsu

1983-01-01

Fallout total β radioactivity was measured in every rainfall in the period from 1962 to 1981. Maximum value of monthly fallout was 462 mCi/km 2 at May 1966. Considering changes of monthly fallout, it was assumed that these 20 years were divided to 3 periods and these changes reflected the history of nuclear explosion tests in the world. Maximum value of annual fallout was 1,154 mCi/km 2 in 1963. Average of annual fallout in 1973 to 1981 was about 1/40 of maximum value. It was confirmed that changes of annual fallout were almost corresponded with changes of annual deposition of 90 Sr and 137 Cs in Tokyo reported by Katsuragi et al. Estimating the staying time of 90 Sr and 137 Cs at Stratosphere by the use of annual fallout of total β radioactivity and annual deposition of these radionuclides, 90 Sr was 1.3 years and 137 Cs was 1.5 years. Also, annual correlation between monthly fallout and monthly rainfall was regarded as significant in only 6 years of these 20 years. (author)

Modelling and simulation the radioactive source-term of fission products in PWR type reactors

International Nuclear Information System (INIS)

Porfirio, Rogilson Nazare da Silva

1996-01-01

The source-term was defined with the purpose the quantify all radioactive nuclides released the nuclear reactor in the case of accidents. Nowadays the source-term is limited to the coolant of the primary circuit of reactors and may be measured or modelled with computer coders such as the TFP developed in this work. The calculational process is based on the linear chain techniques used in the CINDER-2 code. The TFP code considers forms of fission products release from the fuel pellet: Recoil, Knockout and Migration. The release from the gap to the coolant fluid is determined from the ratio between activity measured in the coolant and calculated activity in the gap. Considered the operational data of SURRY-1 reactor, the TFP code was run to obtain the source=term of this reactor. From the measured activities it was verified the reliability level of the model and the employed computational logic. The accuracy of the calculated quantities were compared to the measured data was considered satisfactory. (author)

Characterization of radioactive contaminants and water treatment trials for the Taiwan Research Reactor's spent fuel pool

International Nuclear Information System (INIS)

Huang, Chun-Ping; Lin, Tzung-Yi; Chiao, Ling-Huan; Chen, Hong-Bin

2012-01-01

Highlights: ► Deal with a practical radioactive contamination in Taiwan Research Reactor spent fuel pool water. ► Identify the properties of radioactive contaminants and performance test for water treatment materials. ► The radioactive solids were primary attributed by ruptured spent fuels, spent resins, and metal debris. ► The radioactive ions were major composed by uranium and fission products. ► Diatomite-based ceramic depth filter can simultaneously removal radioactive solids and ions. - Abstract: There were approximately 926 m 3 of water contaminated by fission products and actinides in the Taiwan Research Reactor's spent fuel pool (TRR SFP). The solid and ionic contaminants were thoroughly characterized using radiochemical analyses, scanning electron microscopy equipped with an energy dispersive spectrometer (SEM-EDS), and inductively coupled plasma optical emission spectrometry (ICP-OES) in this study. The sludge was made up of agglomerates contaminated by spent fuel particles. Suspended solids from spent ion-exchange resins interfered with the clarity of the water. In addition, the ionic radionuclides such as 137 Cs, 90 Sr, U, and α-emitters, present in the water were measured. Various filters and cation-exchange resins were employed for water treatment trials, and the results indicated that the solid and ionic contaminants could be effectively removed through the use of <0.9 μm filters and cation exchange resins, respectively. Interestingly, the removal of U was obviously efficient by cation exchange resin, and the ceramic depth filter composed of diatomite exhibited the properties of both filtration and adsorption. It was found that the ceramic depth filter could adsorb β-emitters, α-emitters, and uranium ions. The diatomite-based ceramic depth filter was able to simultaneously eliminate particles and adsorb ionic radionuclides from water.

Immobilization of Ion Exchange radioactive resins of the TRIGA Mark III Nuclear Reactor

International Nuclear Information System (INIS)

Garcia Martinez, H.

1999-01-01

In the last decades many countries in the world have taken interest in the use, availability, and final disposal of dangerous wastes in the environment, within these, those dangerous wastes that contain radioactive material. That is why studies have been made on materials used as immobilization agent of radioactive waste that may guarantee its storage for long periods of time under drastic conditions of humidity, temperature change and biodegradation. In mexico, the development of different applications of radioactive material in the industry, medicine and investigation, have generated radioactive waste, sealed and open sources, whose require a special technological development for its management and final disposal. The present work has as a finality to develop the process and define the agglutinating material, bitumen, cement and polyester resin that permits immobilization of resins of Ionic Exchange contaminated by Barium 153, Cesium 137, Europium 152, Cobalt 60 and Manganese 54 generated from the nuclear reactor TRIGA Mark III. Ionic interchange contaminated resin must be immobilized and is analysed under different established tests by the Mexican Official Standard NOM-019-NUCL-1995 L ow level radioactive wastes package requirements for its near-surface final disposal. Immobilization of ionic interchange contaminated resins must count with the International Standards applicable in this process; in these standards, the following test must be taken in prototype examples: Free-standing water, leachability, compressive strength, biodegradation, radiation stability, thermal stability and burning rate. (Author)

Low and intermediate level radioactive waste processing in plasma reactor

International Nuclear Information System (INIS)

Sauchyn, V.; Khvedchyn, I.; Van Oost, G.

2013-01-01

Methods of low and intermediate level radioactive waste processing comprise: cementation, bituminization, curing in polymer matrices, combustion and pyrolysis. All these methods are limited in their application in the field of chemical, morphological, and aggregate composition of material to be processed. The thermal plasma method is one of the universal methods of RAW processing. The use of electric-arc plasma with mean temperatures 2000 - 8000 K can effectively carry out the destruction of organic compounds into atoms and ions with very high speeds and high degree of conversion. Destruction of complex substances without oxygen leads to a decrease of the volume of exhaust gases and dimension of gas cleaning system. This paper presents the plasma reactor for thermal processing of low and intermediate level radioactive waste of mixed morphology. The equipment realizes plasma-pyrolytic conversion of wastes and results in a conditioned product in a single stage. As a result, the volume of conditioned waste is significantly reduced (more than 10 times). Waste is converted into an environmentally friendly form that suits long-term storage. The leaching rate of macro-components from the vitrified compound is less than 1.10 -7 g/(cm 2 .day). (authors)

The status of the radioactive waste management in Korea

International Nuclear Information System (INIS)

Hyun-Soo Park

2001-01-01

In Korea, fourteen nuclear reactors are in operation and by 2015, a total of twenty eight nuclear reactors will be in operation. The current nuclear share occupies about 34.2 % of the total generating capacity of electricity and 46.3 % of the total production of electricity. The active nuclear program causes an inevitable increase in the build-up of radioactive waste, including spent fuel. Therefore, the reliable and effective management of radioactive waste and spent fuel has become a key for the continuous growth of the nuclear power program. By 2000, a total of 84,413 drums of low and intermediate level waste (LILW) shall be generated and it shall drastically increase to 256,520 drums by 2020. Also, the cumulative amount of spent fuel shall reach 4,623 MTU in 2000 and jump to 18,615 MTU by 2020. By the new national planning, AFR storage facilities for spent fuels shall be built by 2016 and a repository for LILW radioactive disposal shall be in operation by 2008. Even though Korea has a ''wait and see'' policy for spent fuel management, several alternative studies on spent fuel management such as DUPIC have been carried out. In parallel, R and D activities to develop the needed technologies for the permanent disposal of spent fuel and HLW have been implemented. In addition, active R and D on the treatment of radioactive waste from the various nuclear fuel cycle as well as the decontamination and the decommissioning of nuclear facilities are in progress. Many of these studies are pursued in the form of international collaboration with prominent overseas organizations. (author)

Status of low-level radioactive waste management in Korea

Energy Technology Data Exchange (ETDEWEB)

Lee, K.J. [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of). Dept. of Nuclear Engineering

1993-03-01

The Republic of Korea has accomplished dramatic economic growth over the past three decades; demand for electricity has rapidly grown more than 15% per year. Since the first nuclear power plant, Kori-1 [587 MWe, pressurized water reactor (PWR)], went into commercial operation in 1978, the nuclear power program has continuously expanded and played a key role in meeting the national electricity demand. Nowadays, Korea has nine nuclear power plants [eight PWRs and one Canadian natural uranium reactor (CANDU)] in operation with total generating capacity of 7,616 MWe. The nuclear share of total electrical capacity is about 36%; however, about 50% of actual electricity production is provided by these nine nuclear power plants. In addition, two PWRs are under construction, five units (three CANDUs and two PWRs) are under design, and three more CANDUs and eight more PWRs are planned to be completed by 2006. With this ambitious nuclear program, the total nuclear generating capacity will reach about 23,000 MWe and the nuclear share will be about 40% of the total generating capacity in the year 2006. In order to expand the nuclear power program this ambitiously, enormous amounts of work still have to be done. One major area is radioactive waste management. This paper reviews the status of low-level radioactive waste management in Korea. First, the current and future generation of low-level radioactive wastes are estimated. Also included are the status and plan for the construction of a repository for low-level radioactive wastes, which is one of the hot issues in Korea. Then, the nuclear regulatory system is briefly mentioned. Finally, the research and development activities for LLW management are briefly discussed.

Radiological impact on the workers, members of the public, and environment from the partial decommissioning of Pakistan Research Reactor-I and its associated radioactive residues.

Science.gov (United States)

Ali, A; Orfi, S D; Manzur, H; Aslam, M

2001-05-01

The Pakistan Research Reactor-I (PARR-I) is a swimming pool type research reactor originally designed and built for a thermal power of 5 MW using High Enriched Uranium (HEU) fuel. In 1990-1991 the reactor was redesigned, partially decommissioned and recommissioned to operate with Low Enriched Uranium (LEU) fuel at a thermal power of 10 MW. An essential requirement, construction and commissioning of a wet spent fuel storage bay and fabrication of an irradiated fuel transfer cask were completed before actual dismantling of the reactor core. During the partial decommissioning operations, radioactive waste generated included 600 m3 low-level liquid radioactive waste and 14 m3 of solid radioactive waste with an average specific activity of 4.52 Bq ml(-1) and 2.22 kBq g(-1), respectively. External radiation doses of the workers were determined using TLD (NG 6,7) and direct reading dosimeters. The maximum individual external radiation dose received by any worker during this practice was 5 mSv, which was 25% of the annual dose limit of 20 mSv. Detection and measurement of internal contamination was carried out using bioassay techniques. During the whole operation, not a single case of internal contamination was detected. The ambient radiation levels around waste seepage pits are periodically monitored using TLD (G-2 cards) and G. M. radiation survey meters. Underground migration of radioactivity is checked by analyzing seepage water samples taken from boreholes that have been dug at different locations in the vicinity of the radioactive residues. The monitoring around disposal sites containing radioactive residues has been continued during the last 9 y and will be continued in the future. So far, no rise in the environmental gamma radiation dose level and migration of underground radionuclides has been found in the vicinity of these disposal sites. Working personal during the decommissioning of PARR-I have been found to be radiologically safe. Adherence to the ALARA

Released radioactivity reducing facility

International Nuclear Information System (INIS)

Tanaka, Takeaki.

1992-01-01

Upon occurrence of a reactor accident, penetration portions of a reactor container, as a main leakage source from a reactor container, are surrounded by a plurality of gas-tight chambers, the outside of which is surrounded by highly gas-tightly buildings. Branched pipelines of an emergency gas processing system are introduced to each of the gas-tight chambers and they are joined and in communication with an emergency gas processing device. With such a constitution, radioactive materials are prevented from leaking directly from the buildings. Further, pipeline openings of the emergency gas processing facility are disposed in the plurality highly gas-tight penetration chambers. If the radioactive materials are leaked from the reactor to elevate the pressure in the penetration chambers, the radioactive materials are introduced to a filter device in the emergency gas processing facility by way of the branched pipelines, filtered and then released to the atmosphere. Accordingly, the reliability and safety of the system can be improved. (T.M.)

Progress in radioactive graphite waste management

International Nuclear Information System (INIS)

2010-07-01

Radioactive graphite constitutes a major waste stream which arises during the decommissioning of certain types of nuclear installations. Worldwide, a total of around 250 000 tonnes of radioactive graphite, comprising graphite moderators and reflectors, will require management solutions in the coming years. 14 C is the radionuclide of greatest concern in nuclear graphite; it arises principally through the interaction of reactor neutrons with nitrogen, which is present in graphite as an impurity or in the reactor coolant or cover gas. 3 H is created by the reactions of neutrons with 6 Li impurities in graphite as well as in fission of the fuel. 36 Cl is generated in the neutron activation of chlorine impurities in graphite. Problems in the radioactive waste management of graphite arise mainly because of the large volumes requiring disposal, the long half-lives of the main radionuclides involved and the specific properties of graphite - such as stored Wigner energy, graphite dust explosibility and the potential for radioactive gases to be released. Various options for the management of radioactive graphite have been studied but a generally accepted approach for its conditioning and disposal does not yet exist. Different solutions may be appropriate in different cases. In most of the countries with radioactive graphite to manage, little progress has been made to date in respect of the disposal of this material. Only in France has there been specific thinking about a dedicated graphite waste-disposal facility (within ANDRA): other major producers of graphite waste (UK and the countries of the former Soviet Union) are either thinking in terms of repository disposal or have no developed plans. A conference entitled 'Solutions for Graphite Waste: a Contribution to the Accelerated Decommissioning of Graphite Moderated Nuclear Reactors' was held at the University of Manchester 21-23 March 2007 in order to stimulate progress in radioactive graphite waste management

Consequences of severe radioactive releases to Nordic Marine environment

DEFF Research Database (Denmark)

Iosjpe, M.; Isaksson, M.; Joensen, H.P.

- or minor – radioactive releases to Nordic marine environment. As a reference, the release amounts from a 3000 MWth reactor size were used. Based on source term analyses, the chosen release fractions in the study were: iodine 20% (of the total core inventory), caesium 10%, tellurium 10%, strontium 0...

Fuel element replacement and cooling water radioactivity at the Musashi reactor

International Nuclear Information System (INIS)

Nozaki, T.; Honda, T.; Horiuchi, N.; Aizawa, O.; Sato, T.

1988-01-01

The Musashi reactor (TRIGA-II, 100kW) has been operated without any serious troubles since 1963. In 1985 the old Al-cladded fuel elements were replaced with new stainless cladded ones in order to insure a long and safe operation. By using a semi-automatic equipment the old fuel elements have been transferred into the bulk-shielding experimental pool, which was remodelled for the spent-fuel storage. In order to reduce the exposure during the transfer work, the old fuel elements were cooled in the core tank for 3 months. After the replacement, the radioactivities in the cooling water have been drastically changed. The activity of Na-24 decreased about one decade, and the activities of Cr-51, Mn-54, Mn-56, Co-58 and Co-60 increased about two decades. At this conference we will report on the following points: (1) semi-automatic equipment for the transportation of the Al-cladded spent fuel, (2) structure of spent-fuel storage pool, and (3) radioactivity change in the cooling water. (author)

Inventories of radioactive fission products in the core of thermal nuclear reactor

International Nuclear Information System (INIS)

Marinkovic, N.

1977-01-01

As a part of the analysis concerning radiological consequences of a major LWR accident, inventories of the most significant radioactive nuclides and stable fission gases in the core of a PWR type reactor have been calculated. Calculations were performed by the DELFIN code using nuclide data and neutron flux data earlier obtained by the METHUSELAH code. Comparison with simplified calculation method show that it is quite rough for certain nuclides but the accuracy may be sufficient for safety analysis purposes recalling the inaccuracies in the later parts of fission product transport process (author)

Parametric study of the Ignalina reactor building capability as barrier against accidental releases of radioactivity

International Nuclear Information System (INIS)

Blomquist, R.; Johansson, Kjell; Nilsson, Lars.

1993-01-01

The results of a parametric study are offered to the Ignalina plant management staff and to the Lithuanian and Swedish nuclear inspectorates as a basis for a decision whether there is mutual interest in a project for the purpose of strengthening the Ignalina reactor buildings inherent capabilities to provide a barrier against accidental releases of radioactivity. Practical measures to consider are: * establish natural convection of warm air from the steam drums to the tall stack of 150 m height. * reduce the resulting draught of air through the reactor hall floor between the fuel channel shield blocks into the steam drum compartments. * apply filtration to the stack air flow. 18 refs

Application of Bondarenko formalism to fusion reactors

International Nuclear Information System (INIS)

Soran, P.D.; Dudziak, D.J.

1975-01-01

The Bondarenko formalism used to account for resonance self-shielding effects (temperature and composition) in a Reference Theta-Pinch Reactor is reviewed. A material of interest in the RTPR blanket is 93 Nb, which exhibits a large number of capture resonance in the energy region below 800 keV. Although Nb constitutes a small volume fraction of the blanket, its presence significantly affects the nucleonic properties of the RTPR blanket. The effects of self-shielding in 93 Nb on blanket parameters such as breeding ratio, total afterheat, radioactivity, magnet-coil heating and total energy depositions have been studied. Resonance self-shielding of 93 Nb, as compared to unshielded cross sections, will increase tritium breeding by approximately 7 percent in the RTPR blanket and will decrease blanket radioactivity, total recoverable energy, and magnet-coil heating. Temperature effects change these parameters by less than 2 percent. The method is not restricted to the RTPR, as a single set of Bondarenko f-factors is suitable for application to a variety of fusion reactor designs

Radiation protection at the RA Reactor in 1985, Part -4, decontamination and treatment of solid radioactive materials for the needs of RA reactor

International Nuclear Information System (INIS)

Plecas, I.; Vukovic, Z.; Blagojevic, R.; Kostadinovic, A.

1985-01-01

This report describes the activity of the decontamination and treatment team for the needs of the RA reactor, its equipment, working conditions, methods for decontamination, means of decontamination, type and quantity of decontaminated surfaces, number of decontaminated objects, quantity of collected radioactive solid wastes, their packaging, transport to the storage place and topography od radiation field in the storage during 1985 [sr

A comparison study on radioactive waste management effectiveness in various nuclear fuel cycles

International Nuclear Information System (INIS)

Ko, Won Il; Kim, Ho Dong

2001-07-01

This study examines whether the DUPIC (Direct Use of Spent PWR Fuel In CANDU) fuel cycle make radioactive waste management more effective, by comparing it with other fuel cycles such as the PWR (Pressurized Water Reactor) once-through cycle, the HWR (Pressurized Heavy Water Reactor) once-through cycle and the thermal recycling option to use an existing PWR with MOX (Mixed Oxide) fuel. This study first focuses on the radioactive waste volume generated in all fuel cycle steps, which could be one of the measures of effectiveness of the waste management. Then the total radioactive waste disposition cost is estimated based on two units measuring; m3/GWe-yr and US$/GWe-yr. We find from the radioactive waste volume estimation that the DUPIC fuel cycle could have lower volumes for milling tailings, low level waste and spent fuel than those of other fuel cycle options. From the results of the disposition cost analysis, we find that the DUPIC waste disposition cost is the lowest among fuel cycle options. If the total waste disposition cost is used as a proxy for quantifying the easiness or difficulty in managing wastes, then the DUPIC option actually make waste management easier

Conditioning for definitive storage of radioactive graphite bricks from reactor decommissioning

International Nuclear Information System (INIS)

Costes, J.R.; Koch, C.; Tassigny, C. de; Vidal, H.; Raymond, A.

1990-01-01

The decommissioning of gas-graphite reactors in the EC (e.g. French UNGGs, British Magnox reactors and AGRs, and reactors in Spain and in Italy) will produce large amounts of graphite bricks. This graphite cannot be accepted without particular conditioning by the existing shallow land disposal sites. The aim of the study is to examine the behaviour of graphite waste and to develop a conditioning technique which makes this waste acceptable for shallow land disposal sites. 18 kg of graphite core samples with an outside diameter of 74 mm were removed from the G2 gas-cooled reactor at Marcoule. Their radioactivity is highly dependent on the position of the graphite bricks inside the reactor. Measured results indicate an activity range of 100-400 MBq/kg with 90% Tritium, 5% 14 C, 3% 60 Co, 1.5% 63 Ni. Repeated porosity analyses showed that open porosity ranging from 0 to 100 μm exceeded 23 vol% in the graphite. Water penetration kinetics were investigated in unimpregnated graphite and resulted in impregnation by water of 50-90% of the open porosity. Preliminary lixiviation tests on the crude samples showed quick lixidegree of Cs (several per cent) and of 60 Co, and 133 Ba at a lesser degree. The proposed conditioning technique does not involve a simple coating but true impregnation by a tar-epoxy mixture. The bricks recovered intact from the core by robot services will be placed one by one inside a cylindrical metallic container. But this container may corrode and the bricks may become fragmented in the future, the normally porous graphite will be unaffected by leaching since it is proved that all pores larger than 0.1 μm will be filled with the tar-epoxy mixture. This is a true long-term waste packaging concept. The very simple technology required for industrial implementation is discussed

The conceptual flowsheet of effluent treatment during total gelation of uranium process for preparing ceramic UO2 particles of high temperature gas-cooled reactors

International Nuclear Information System (INIS)

Quan Ying; Chen Xiaotong; Wang Yang; Liu Bing; Tang Yaping; Tang Chunhe

2014-01-01

Today, more and more people pay attention to the environmental protection and ecological environment. Along with the development of nuclear industry, many radioactive effluents may be discharged into environment, which can lead to the pollutions of water, atmosphere and soil. So radioactive effluents including low-activity and medium-level wastes solution treatments have been becoming one of significant subjects. High temperature gas-cooled reactor (HTR) is one of advanced nuclear reactors owing to its reliability, security and broad application in which the fabrication of spherical fuel element is a key technology. During the production of spherical fuel elements, the radioactive effluent treatment is necessary. Referring to the current treatment technologies and methods, the conceptual flowsheet of low-level radioactive effluent treatment during preparing spherical fuel elements was summarized which met the 'Zero Emission' demand. (authors)

Radiation protection at the RA Reactor in 1993, Part II, Decontamination and actions, collection of liquid effluents and solid radioactive waste

International Nuclear Information System (INIS)

Mandic, M.; Vukovic, Z.; Lazic, S.; Plecas, I.; Voko, A.

1993-01-01

Certain amount of solid waste results from RA reactor operation, the mean quantity of which depends on the duration of reactor operation and related activities. During repair, when reactor is not operated as well under accidental conditions, the quantity of waste is higher, dependent on the type of repair and comprehensiveness of decontamination of the working surface, contaminated tools and components. The waste is sorted and packed on the spot where they appeared according to the existing regulations and principles of radiation protection with aim to minimize unnecessary exposure of the radiation protection personnel who deals with control, transport, radioactive waste treatment and decontamination. During exceptional operations (decontamination, repair, bigger volume of contaminated material, etc.) professional staff of the Radiation protection department gives recommendations and helps in planning the actions related to repair, sorting and packaging of radioactive waste in special containers, identification of the contaminants, etc. [sr

Fallout total. beta. radioactivity in every rainfall in Aichi prefecture

Energy Technology Data Exchange (ETDEWEB)

Ohnuma, Shoko; Chaya, Kunio; Shimizu, Michihiko; Tomita, Ban-ichi; Hamamura, Norikatsu (Aichi Prefectural Inst. of Public Health, Nagoya (Japan))

1983-01-01

Fallout total ..beta.. radioactivity was measured in every rainfall in the period from 1962 to 1981. Maximum value of monthly fallout was 462 mCi/km/sup 2/ at May 1966. Considering changes of monthly fallout, it was assumed that these 20 years were divided to 3 periods and these changes reflected the history of nuclear explosion tests in the world. Maximum value of annual fallout was 1,154 mCi/km/sup 2/ in 1963. Average of annual fallout in 1973 to 1981 was about 1/40 of maximum value. It was confirmed that changes of annual fallout were almost corresponded with changes of annual deposition of /sup 90/Sr and /sup 137/Cs in Tokyo reported by Katsuragi et al. Estimating the staying time of /sup 90/Sr and /sup 137/Cs at Stratosphere by the use of annual fallout of total ..beta.. radioactivity and annual deposition of these radionuclides, /sup 90/Sr was 1.3 years and /sup 137/Cs was 1.5 years. Also, annual correlation between monthly fallout and monthly rainfall was regarded as significant in only 6 years of these 20 years.

Management of nontritium radioactive wastes from fusion power plants

International Nuclear Information System (INIS)

Kaser, J.D.; Postma, A.K.; Bradley, D.J.

1976-09-01

This report identifies nontritium radioactive waste sources for current conceptual fusion reactor designs. Quantities and compositions of the radwaste are estimated for the tokamaks of the University of Wisconsin (UWMAK-I), the Princeton Plasma Physics Laboratory (PPPL), and the Oak Ridge National Laboratory (ORNL); the Reference Theta Pinch Reactor of the Los Alamos Scientific Laboratory (LASL); and the Minimum Activation Blanket of the Brookhaven National Laboratory (BNL). Disposal of large amounts of radioactive waste appears necessary for fusion reactors. Although the curie (Ci) level of the wastes is comparable to that of fission products in fission reactors, the isotopes are less hazardous, and have shorter half-lives. Therefore radioactivity from fusion power production should pose a smaller risk than radioactivity from fission reactors. Radioactive waste sources identified for the five reference plants are summarized. Specific radwaste treatments or systems had to be assumed to estimate these waste quantities. Future fusion power plant conceptual designs should include radwaste treatment system designs so that assumed designs do not have to be used to assess the environmental effects of the radioactive waste

Reactor container spray device

International Nuclear Information System (INIS)

Yanai, Ryoichi.

1980-01-01

Purpose: To enable decrease in the heat and the concentration of radioactive iodine released from the reactor vessel into the reactor container in the spray device of BWR type reactors. Constitution: A plurality of water receiving trays are disposed below the spray nozzle in the dry well and communicated to a pressure suppression chamber by way of drain pipeways passing through a diaphragm floor. When the recycling system is ruptured and coolants in the reactor vessel and radioactive iodine in the reactor core are released into the dry well, spray water is discharged from the spray nozzle to eliminate the heat and the radioactive iodine in the dry well. In this case, the receiving trays collect the portions of spray water whose absorption power for the heat and radioactive iodine is nearly saturated and falls them into the pool water of the pressure suppression chamber. Consequently, other portions of the spray water that still possess absorption power can be jetted with no hindrance, to increase the efficiency for the removal of the heat and iodine of the spray droplets. (Horiuchi, T.)

Development of radioactivity estimation system considering radioactive nuclide movement

International Nuclear Information System (INIS)

Fukumura, Nobuo; Miyamoto, Yoshiaki

2010-01-01

A radioactivity estimation system considering radioactive nuclide movement is developed to integrate the established codes and the code system for decommissioning of sodium cooled fast reactor (FBR). The former are the codes for estimation of radioactivity movement in sodium coolant of fast reactor which are named SAFFIRE, PSYCHE and TTT. The latter code system is to estimate neutron irradiation activity (COSMARD-RRADO). It is paid special attention to keep the consistency of input data used among these codes and also the simplification of their interface. A new function is added to the estimation system, to estimate minor FP inventory caused by the fission of impurities contained in the coolant and slight fuel material attached on the fuel cladding. To check the evaluation system, the system is applied with radioactivity data of the preceding FBR such as BN-350, JOYO and Monju. Agreement between the analysis results and the measurement is well satisfactory. The uncertainty of the code system is within several tens per cent for the activation of primary coolant (Na-22) and factor of 2-4 for the estimation of radioactivity inventory in sodium coolant. (author)

Declassification of radioactive water from a pool type reactor after nuclear facility dismantling

Science.gov (United States)

Arnal, J. M.; Sancho, M.; García-Fayos, B.; Verdú, G.; Serrano, C.; Ruiz-Martínez, J. T.

2017-09-01

This work is aimed to the treatment of the radioactive water from a dismantled nuclear facility with an experimental pool type reactor. The main objective of the treatment is to declassify the maximum volume of water and thus decrease the volume of radioactive liquid waste to be managed. In a preliminary stage, simulation of treatment by the combination of reverse osmosis (RO) and evaporation have been performed. Predicted results showed that the combination of membrane and evaporation technologies would result in a volume reduction factor higher than 600. The estimated time to complete the treatment was around 650 h (25-30 days). For different economical and organizational reasons which are explained in this paper, the final treatment of the real waste had to be reduced and only evaporation was applied. The volume reduction factor achieved in the real treatment was around 170, and the time spent for treatment was 194 days.

Calculations of fuel burn-up and radionuclide inventory in the syrian miniature neutron source reactor using the WIMSD4 code

International Nuclear Information System (INIS)

Khattab, K.

2005-01-01

Calculations of the fuel burn up and radionuclide inventory in the Miniature Neutron Source Reactor after 10 years (the reactor core expected life) of the reactor operating time are presented in this paper. The WIMSD4 code is used to generate the fuel group constants and the infinite multiplication factor versus the reactor operating time for 10, 20, and 30 kW operating power levels. The amounts of uranium burnt up and plutonium produced in the reactor core, the concentrations and radioactivities of the most important fission product and actinide radionuclides accumulated in the reactor core, and the total radioactivity of the reactor core are calculated using the WIMSD4 code as well

Greater-than-Class C low-level radioactive waste characterization. Appendix A-3: Basis for greater-than-Class C low-level radioactive waste light water reactor projections

International Nuclear Information System (INIS)

Mancini, A.; Tuite, P.; Tuite, K.; Woodberry, S.

1994-09-01

This study characterizes low-level radioactive waste types that may exceed Class C limits at light water reactors, estimates the amounts of waste generated, and estimates radionuclide content and distribution within the waste. Waste types that may exceed Class C limits include metal components that become activated during operations, process wastes such as cartridge filters and decontamination resins, and activated metals from decommissioning activities. Operating parameters and current management practices at operating plants are reviewed and used to estimate the amounts of low-level waste exceeding Class C limits that is generated per fuel cycle, including amounts of routinely generated activated metal components and process waste. Radionuclide content is calculated for specific activated metals components. Empirical data from actual low-level radioactive waste are used to estimate radionuclide content for process wastes. Volumes and activities are also estimated for decommissioning activated metals that exceed Class C limits. To estimate activation levels of decommissioning waste, six typical light water reactors are modeled and analyzed. This study does not consider concentration averaging

Radioactivity concentrations in Bavarian surface water after the Chernobyl reactor accident. Radioaktive Belastungen des Wassers in Bayern nach dem Reaktorunfall in Tschernobyl

Energy Technology Data Exchange (ETDEWEB)

Amann, W; Friedmann, L; Lux, D

1986-01-01

The special investigation programme for monitoring radioactive immissions, which was primarily concerned with drinking water, initially led to the discovery of high rates of precipitate pollution by I-131, I-132, Cs-134, Cs-137 and Te-132. Since initial investigations had revealed no increases in total alpha and tritium values, gamma-spectrometric determinations were effected exclusively for single nuclides. Later on, a considerable accumulation of the nuclides Cs-134, Cs-137 and Ru-103 was discoverd in the sediments of surface bodies of water and in sewage sludges. The effects of the reactor accident on surface water are still being monitored in a long-term metering programme. (DG).

Waste disposal from the light water reactor fuel cycle

International Nuclear Information System (INIS)

Costello, J.M.; Hardy, C.J.

1981-05-01

Alternative nuclear fuel cycles for support of light water reactors are described and wastes containing naturally occurring or artificially produced radioactivity reviewed. General principles and objectives in radioactive waste management are outlined, and methods for their practical application to fuel cycle wastes discussed. The paper concentrates upon management of wastes from upgrading processes of uranium hexafluoride manufacture and uranium enrichment, and, to a lesser extent, nuclear power reactor wastes. Some estimates of radiological dose commitments and health effects from nuclear power and fuel cycle wastes have been made for US conditions. These indicate that the major part of the radiological dose arises from uranium mining and milling, operation of nuclear reactors, and spent fuel reprocessing. However, the total dose from the fuel cycle is estimated to be only a small fraction of that from natural background radiation

Environmental radioactivity and water supply. Pt. 3. The contamination of surface waters in Germany after the Chernobyl reactor accident

International Nuclear Information System (INIS)

Haberer, K.

1988-03-01

After the reactor accident, german surface waters have been monitored in numerous positions over a long period of time. The highest concentrations of iodine 131 occurred in the lower german region of the Danube river with more than 200 Bg/l whereas the Rhine river had the lowest concentrations. The sudden rise of the radioactivity of the river water have been followed by a slower decrease but nevertheless much faster than the radioactive decay. Probably this is caused by the interaction with river sediments. For the german lakes and reservoirs it was very important whether the water masses have been stratified or not when the radioactive cloud arrived. Where this was the case, the radioactive contaminants remained predominantly in the upper layer, the epilimnion for a long period of time [fr

Measurement of total body radioactivity in man

International Nuclear Information System (INIS)

Naversten, Y.

1982-01-01

Techniques for the determination of whole-body radioactivity in man using uncollimated NaI(Tl) detectors have been studied. Geometrical effects and photon attenuation effects due to the different shapes of humans as well as due to varying in-vivo radioactivity distributions have been evaluated particularly for scanning-bed geometries and the chair geometry. Theoretically it is shown that the attenuation effects are generally dominating, for full-energy-peak pulse-range methods. For the application in radiation protection a cheap and simple chair-geometry unit has been constructed and used at various places distantly from the home-laboratory, for studies of body activity of Cs-137 in northern Sweden. High body activities were found particularly in reindeer-breeding Lapps. The elimination rate of Cs-137 in man was studied in the stationary whole-body counter in Lund as well as with the field-system. For the study of the performances at low and high photon energies clinical applications of methods for gastro-intestinal absorption of vitamin B12 (Co-57; 122 keV) and total body potassium determination (K-40; 1.46 MeV, K-42; 1.52 MeV) have been evaluated. Theoretical and experimental results as well as experiences of applications in radiation protection and medicine show that the scanning-bed geometry effectively evens out redistributional effects. For optimum results, however, scatter-energy pulse-ranges rather than full-energy-peak ranges should be used. (Auth.)

Radiation protection at the RA Reactor in 1989, Part -2, Decontamination, collection of treatment of fluid and solid radioactive waste, Annex 3

International Nuclear Information System (INIS)

Mandic, M.; Vukovic, Z.; Plecas, I.; Knezevic, Lj.; Lazic, S.; Bacic, S.

1989-01-01

Certain amount of solid waste results from RA reactor operation, the mean quantity of which depends on the duration of reactor operation and related activities. During repair, when reactor is not operated as well under accidental conditions, the quantity of waste is higher, dependent on the type of repair and comprehensiveness of decontamination of the working surface, contaminated tools and components. The waste is sorted and packed on the spot where they appeared according to the existing regulations and principles of radiation protection with aim to minimize unnecessary exposure of the radiation protection personnel who deals with control, transport, radioactive waste treatment and decontamination. During exceptional operations (decontamination, repair, bigger volume of contaminated material, etc.) professional staff of the Radiation protection department gives recommendations and helps in planning the actions related to repair, sorting and packaging of radioactive waste in special containers, identification of the contaminants, etc. [sr

Radioactive waste management in nuclear power plants with WWER-type reactors

Energy Technology Data Exchange (ETDEWEB)

Dlouhy, Z; Napravnik, J; Safar, O

1975-05-01

The possibilities of radioactive waste solidification in nuclear power plants with LWR reactors (of the WWER type) and the problems of their safe storage in Czechoslovakia are discussed. The most suitable method for the treatment of emitted sorbents and concentrates seems to be their incorporation in bitumen or concrete. In the disposal of solidified blocks all requirements should be met including the selection of suitable sites and of convenient methods of transportation. A preliminary economic estimate shows that the storage of bitumen-incorporated wastes in trenches seems to be less expensive from the point of view of exploitation of the storage facility as well as from the point of view of investment.

Code for calculation of spreading of radioactivity in reactor containment systems

International Nuclear Information System (INIS)

Vertes, P.

1992-09-01

A detailed description of the new version of TIBSO code is given, with applications for accident analysis in a reactor containment system. The TIBSO code can follow the nuclear transition and the spatial migration of radioactive materials. The modelling of such processes is established in a very flexible way enabling the user to investigate a wide range of problems. The TIBSO code system is described in detail, taking into account the new developments since 1983. Most changes improve the capabilities of the code. The new version of TIBSO system is written in FORTRAN-77 and can be operated both under VAX VMS and PC DOS. (author) 5 refs.; 3 figs.; 21 tabs

Decommissioning of Salaspils nuclear reactor

International Nuclear Information System (INIS)

Abramenkovs, A.; Malnachs, J.; Popelis, A.

2002-01-01

In May 1995, the Latvian Government decided to shut down the Research Reactor Salaspils (SRR) and to dispense with nuclear energy in future. The reactor has been out of operation since July 1998. A conceptual study for the decommissioning of SRR has been carried out by Noell-KRC-Energie- und Umwelttechnik GmbH from 1998-1999. he Latvian Government decided on 26 October 1999 to start the direct dismantling to 'green field' in 2001. The results of decommissioning and dismantling performed in 1999-2001 are presented and discussed. The main efforts were devoted to collecting and conditioning 'historical' radioactive waste from different storages outside and inside the reactor hall. All radioactive material more than 20 tons were conditioned in concrete containers for disposal in the radioactive waste depository 'Radons' in the Baldone site. Personal protective and radiation measurement equipment was upgraded significantly. All non-radioactive equipment and material outside the reactor buildings were free-released and dismantled for reuse or conventional disposal. Weakly contaminated material from the reactor hall was collected and removed for free-release measurements. The technology of dismantling of the reactor's systems, i.e. second cooling circuit, zero power reactors and equipment, is discussed in the paper. (author)

Calculated model of radioactive fission and corrosion product accumulation and distribution in a fast reactor sodium coolant circuit

International Nuclear Information System (INIS)

Kizin, V.D.; Konyashov, V.V.

1987-01-01

A simple calculation procedure of radioactive products accumulation and distribution in a primary circuit has been developed on the basis of experimental investigations at the BOR-60 reactor. Common knowledge on the impurity products transfer at the liquid-solid and liquid-gas phase boundary is taken. Use is made of the typical in reactor physics relationships for the description of the products transition to the equipment surfaces, of fission products release, metal corrosion and others. Satisfactory agreement of the calculation data with the experimental ones has been obtained. (orig.)

An estimation of exposure from gaseous and volatile radioactive effluents released from EWA reactor between 1971 and 1975

International Nuclear Information System (INIS)

Filipiak, B.; Nowicki, K.

1979-01-01

The paper gives an estimation of radiation doses for individuals due to gaseous radioactive effluents released from EWA reactor between 1971 and 1975. The doses were estimated for three organs, three groups of people: adults, teenagers and children and for three of the most important exposure paths: the external radiation from a passing cloud, inhalation and from milk ingestion. The results of calculations indicate that the radiation doses received by individuals living in the vicinity of EWA reactor were much below the limit doses or those due to the background radiation. (author)

Decommissioning of TRIGA Mark II type reactor

Energy Technology Data Exchange (ETDEWEB)

Hwang, Dooseong; Jeong, Gyeonghwan; Moon, Jeikwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2012-10-15

The first research reactor in Korea, KRR 1, is a TRIGA Mark II type with open pool and fixed core. Its power was 100 kWth at its construction and it was upgraded to 250 kWth. Its construction was started in 1957. The first criticality was reached in 1962 and it had been operated for 36,000 hours. The second reactor, KRR 2, is a TRIGA Mark III type with open pool and movable core. These reactors were shut down in 1995, and the decision was made to decommission both reactors. The aim of the decommissioning activities is to decommission the KRR 2 reactor and decontaminate the residual building structures and site, and to release them as unrestricted areas. The KRR 1 reactor was decided to be preserve as a historical monument. A project was launched for the decommissioning of these reactors in 1997, and approved by the regulatory body in 2000. A total budget for the project was 20.0 million US dollars. It was anticipated that this project would be completed and the site turned over to KEPCO by 2010. However, it was discovered that the pool water of the KRR 1 reactor was leaked into the environment in 2009. As a result, preservation of the KRR 1 reactor as a monument had to be reviewed, and it was decided to fully decommission the KRR 1 reactor. Dismantling of the KRR 1 reactor takes place from 2011 to 2014 with a budget of 3.25 million US dollars. The scope of the work includes licensing of the decommissioning plan change, removal of pool internals including the reactor core, removal of the thermal and thermalizing columns, removal of beam port tubes and the aluminum liner in the reactor tank, removal of the radioactive concrete (the entire concrete structure will not be demolished), sorting the radioactive waste (concrete and soil) and conditioning the radioactive waste for final disposal, and final statuses of the survey and free release of the site and building, and turning over the site to KEPCO. In this paper, the current status of the TRIGA Mark-II type reactor

Reactors physics. Bases of nuclear physics

International Nuclear Information System (INIS)

Diop, Ch.M.

2006-01-01

The aim of nuclear reactor physics is to quantify the relevant macroscopic data for the characterization of the neutronic state of a reactor core and to evaluate the effects of radiations (neutrons and gamma radiations) on organic matter and on inorganic materials. This first article presents the bases of nuclear physics in the context of nuclear reactors: 1 - reactor physics and nuclear physics; 2 - atomic nucleus - basic definitions: nucleus constituents, dimensions and mass of the atomic nucleus, mass defect, binding energy and stability of the nucleus, strong interaction, nuclear momentums of nucleons and nucleus; 3 - nucleus stability and radioactivity: equation of evolution with time - radioactive decay law; alpha decay, stability limit of spontaneous fission, beta decay, electronic capture, gamma emission, internal conversion, radioactivity, two-body problem and notion of radioactive equilibrium. (J.S.)

Quantities of actinides in nuclear reactor fuel cycles

International Nuclear Information System (INIS)

Ang, K.P.

1975-01-01

The quantities of plutonium and other fuel actinides have been calculated for equilibrium fuel cycles for 1000 MW reactors of the following types: water reactors fueled with slightly enriched uranium, water reactors fueled with plutonium and natural uranium, fast-breeder reactors, gas-cooled reactors fueled with thorium and highly enriched uranium, and gas-cooled reactors fueled with thorium, plutonium, and recycled uranium. The radioactivity levels of plutonium, americium, and curium processed yearly in these fuel cycles are greatest for the water reactors fueled with natural uranium and recycled plutonium. The total amount of actinides processed is calculated for the predicted future growth of the United States nuclear power industry. For the same total installed nuclear power capacity, the introduction of the plutonium breeder has little effect upon the total amount of plutonium processed in this century. The estimated amount of plutonium in the low-level process wastes in the plutonium fuel cycles is comparable to the amount of plutonium in the high-level fission product wastes. The amount of plutonium processed in the nuclear fuel cycles can be considerably reduced by using gas-cooled reactors to consume plutonium produced in uranium-fueled water reactors. These, and other reactors dedicated for plutonium utilization, could be co-located with facilities for fuel reprocessing and fuel fabrication to eliminate the off-site transport of separated plutonium. (U.S.)

Low-level radioactive waste management in EDF nuclear power plants (FRANCE)

International Nuclear Information System (INIS)

Boussard, C.

1991-01-01

This paper shows some recent examples of Low-level radioactive waste management in EDF nuclear power plants: - Radioactive liquid wastes proceeding from steam generators leaching (NOGENT SUR SEINE-1 REACTOR) - Thermal insulation proceeding from heat exchanger and blower (CHINON-2 REACTOR) - Old iron from reactor dismantling (CHINON-3 REACTOR, MARCOULE G1 REACTOR, MARCOULE G2-G3 REACTORS) - fresh air filter and fire detector - CHINON-2 REACTOR breaker chambers

Radioactivity in the environment of the RA nuclear reactor in Vinca for the period 1977-1980. Material prepared for the RA reactor safety report; Radioaktivnost okoline nuklearnog reaktora RA u Vinci u periodu 1977-1980, Materijal pripremljen za izradu Sigurnosnog izvestaja za reaktor RA

Energy Technology Data Exchange (ETDEWEB)

Ajdacic, N; Martinc, R [Institute of nuclear sciences Boris Kidric, Vinca, Beograd (Yugoslavia)

1980-12-15

Review of the environmental monitoring data presented in this report is prepared for the RA reactor safety report. These data resulted from four-year monitoring of precipitations and deposited dust. Measurements were done daily. In addition to these data, tables contain mean daily values, total monthly values of beta activities of precipitation from 1977 - 1980. Radioactivity control of the RA reactor environment showed that there was no significant discrepancy compared to the mean values for several years, apart from seasonal variations and meteorological influences. In the period from October 1976 to mid 1978 a number of higher values were recorded probably due to nuclear explosions. During 1979 the general activity level was relatively low, showing increase tendency during 1980.

Characterization of radioactive contaminants and water treatment trials for the Taiwan Research Reactor's spent fuel pool

Energy Technology Data Exchange (ETDEWEB)

Huang, Chun-Ping, E-mail: chunping@iner.gov.tw [Institute of Nuclear Energy Research, 1000, Wenhua Road, Jiaan Village, Longtan Township, Taoyuan County 32546, Taiwan, ROC (China); Lin, Tzung-Yi; Chiao, Ling-Huan; Chen, Hong-Bin [Institute of Nuclear Energy Research, 1000, Wenhua Road, Jiaan Village, Longtan Township, Taoyuan County 32546, Taiwan, ROC (China)

2012-09-30

Highlights: Black-Right-Pointing-Pointer Deal with a practical radioactive contamination in Taiwan Research Reactor spent fuel pool water. Black-Right-Pointing-Pointer Identify the properties of radioactive contaminants and performance test for water treatment materials. Black-Right-Pointing-Pointer The radioactive solids were primary attributed by ruptured spent fuels, spent resins, and metal debris. Black-Right-Pointing-Pointer The radioactive ions were major composed by uranium and fission products. Black-Right-Pointing-Pointer Diatomite-based ceramic depth filter can simultaneously removal radioactive solids and ions. - Abstract: There were approximately 926 m{sup 3} of water contaminated by fission products and actinides in the Taiwan Research Reactor's spent fuel pool (TRR SFP). The solid and ionic contaminants were thoroughly characterized using radiochemical analyses, scanning electron microscopy equipped with an energy dispersive spectrometer (SEM-EDS), and inductively coupled plasma optical emission spectrometry (ICP-OES) in this study. The sludge was made up of agglomerates contaminated by spent fuel particles. Suspended solids from spent ion-exchange resins interfered with the clarity of the water. In addition, the ionic radionuclides such as {sup 137}Cs, {sup 90}Sr, U, and {alpha}-emitters, present in the water were measured. Various filters and cation-exchange resins were employed for water treatment trials, and the results indicated that the solid and ionic contaminants could be effectively removed through the use of <0.9 {mu}m filters and cation exchange resins, respectively. Interestingly, the removal of U was obviously efficient by cation exchange resin, and the ceramic depth filter composed of diatomite exhibited the properties of both filtration and adsorption. It was found that the ceramic depth filter could adsorb {beta}-emitters, {alpha}-emitters, and uranium ions. The diatomite-based ceramic depth filter was able to simultaneously

Radioactive nuclides in nuclear reactors

International Nuclear Information System (INIS)

Akatsu, Eiko

1982-12-01

In the Nuclear Engineering School of JAERI, many courses are presented for the people working in and around nuclear reactors. The curricula of the courses contain also chemical subject materials. With reference to the foreign curricula, a plan of educational subject material of chemistry was considered for students of the school in the previous report (JAERI-M 9827), where the first part of the plan, ''Fundamentals of Reactor Chemistry'', was reviewed. This report is a review of the second part of the plan containing fission products chemistry, actinoids elements chemistry and activated reactor materials chemistry. (author)

Progress in radioactive graphite waste management. Additional information

International Nuclear Information System (INIS)

2010-06-01

Radioactive graphite constitutes a major waste stream which arises during the decommissioning of certain types of nuclear installations. Worldwide, a total of around 250 000 tonnes of radioactive graphite, comprising graphite moderators and reflectors, will require management solutions in the coming years. 14 C is the radionuclide of greatest concern in nuclear graphite; it arises principally through the interaction of reactor neutrons with nitrogen, which is present in graphite as an impurity or in the reactor coolant or cover gas. 3 H is created by the reactions of neutrons with 6 Li impurities in graphite as well as in fission of the fuel. 36 Cl is generated in the neutron activation of chlorine impurities in graphite. Problems in the radioactive waste management of graphite arise mainly because of the large volumes requiring disposal, the long half-lives of the main radionuclides involved and the specific properties of graphite - such as stored Wigner energy, graphite dust explosibility and the potential for radioactive gases to be released. Various options for the management of radioactive graphite have been studied but a generally accepted approach for its conditioning and disposal does not yet exist. Different solutions may be appropriate in different cases. In most of the countries with radioactive graphite to manage, little progress has been made to date in respect of the disposal of this material. Only in France has there been specific thinking about a dedicated graphite waste-disposal facility (within ANDRA): other major producers of graphite waste (UK and the countries of the former Soviet Union) are either thinking in terms of repository disposal or have no developed plans. A conference entitled 'Solutions for Graphite Waste: a Contribution to the Accelerated Decommissioning of Graphite Moderated Nuclear Reactors' was held at the University of Manchester 21-23 March 2007 in order to stimulate progress in radioactive graphite waste management

Radioactive waste management at Institute for Nuclear Research (ICN) - Pitesti

International Nuclear Information System (INIS)

Bujoreanu, C.

2004-01-01

The amounts of liquid and solid wastes accumulated at the Radioactive Wastes Treatment Plant are given. The technologies used for the treatment and conditioning of radioactive wastes are presented. The final product is metallic drum-concrete-radioactive wastes (type A package) for the final disposal at the National Repository Baita, Bihor. The facilities for radioactive waste management at ICN Pitesti are: Plant for treatment, with uranium recovery of liquid radioactive waste resulting from the fabrication of CANDU type nuclear fuel; Plant for treatment of low-active liquid wastes; Plant for conditioning in concrete of the radioactive concentrate obtained during the evaporation treatment of liquid radioactive waste; Plant for incineration of solid radioactive waste contaminated with natural uranium; Plant for treatment and conditioning of organic liquid radioactive waste with tritium content. This wastes are generated by Cernavoda-NPP operation; Plant for conditioning into bitumen of spent ion exchangers at TRIGA reactor. The existing Facility is Baita repository - with two rock cavities of an uranium mine and the total capacity of 21000 containers (200 l drums)

Software application for a total management of a radioactive facility

International Nuclear Information System (INIS)

Mirpuri, E.; Escudero, R.; Macias, M.T.; Perez, J.; Sanchez, A.; Usera, F.

2008-01-01

The use of radiological material and/or equipment that generate ionizing radiation is widely extended in biological research. In every laboratory there are a large variety of methods, operations, techniques, equipment, radioisotopes and users related to the work with ionizing radiation. In order to control the radioactive material, users and the whole facility a large number of documents, databases and information is necessary to be created by the manager of the Radioactivity Facility. This kind of information is characterized by a constant and persistent manipulation and includes information of great importance such as the general management of the radioactive material and waste management, exposed workers vigilance, controlled areas access, laboratory and equipment reservations, radiological inspections, etc. These activities are often complicated by the fact that the main manager of the radioactive facility is also in charge of bio-safety and working prevention issues so the documents to generate and manipulate and the procedures to develop are multiplied. A procedure to access and manage all these files is highly recommended in order to optimize the general management of the facility, avoiding loss of information, automating all the activities and allowing data necessary for control easily accessible. In this work we present a software application for a total management of the facility. This software has been developed by the collaboration of six of the most important research centers from Spain in coordination with the company 'Appize soluciones'. This is a flexible and versatile application that adapts to any specific need of every research center, providing the appropriate reports and checklist that speed up to general management and increase the ease of writing the official documents, including the Operations Book. (author)

RA Research nuclear reactor, Part II: radiation protection at the RA reactor in 1987

International Nuclear Information System (INIS)

Ninkovic, M.; Ajdacic, N.; Zaric, M.; Vukovic, Z.

1987-01-01

Radiation protection tasks which enable safe operation of the RA reactor, and are defined according the the legal regulations and IAEA safety recommendations are sorted into four categories in this report: (1) Control of the working environment, dosimetry at the RA reactor and radiation protection; (2) Radioactivity control in the vicinity of the reactor and meteorology measurements; (3) Decontamination and relevant actions, collecting and treatment of fluid effluents; and and solid radioactive wastes [sr

Radiation protection at the RA Reactor in 1988, Part -2, RA reactor annual report

International Nuclear Information System (INIS)

Ninkovic, M.; Ajdacic, N.; Zaric, M.; Vukovic, Z.

1988-01-01

Radiation protection tasks which enable safe operation of the RA reactor, and are defined according the the legal regulations and IAEA safety recommendations are sorted into four categories in this report: (1) Control of the working environment, dosimetry at the RA reactor and radiation protection; (2) Radioactivity control in the vicinity of the reactor and meteorology measurements; (3) Decontamination and relevant actions, collecting and treatment of fluid effluents; and and solid radioactive wastes [sr

Radiation protection at the RA Reactor in 1995, Part -2, Annex 2, Decontamination and actions, collection of liquid effluents and solid radioactive waste

International Nuclear Information System (INIS)

Mandic, M.; Vukovic, Z.; Lazic, S.; Plecas, I.; Voko, A.

1995-01-01

Certain amount of solid waste results from RA reactor operation, the mean quantity of which depends on the duration of reactor operation and related activities. During repair, when reactor is not operated as well under accidental conditions, the quantity of waste is higher, dependent on the type of repair and comprehensiveness of decontamination of the working surface, contaminated tools and components. The waste is sorted and packed on the spot where they appeared according to the existing regulations and principles of radiation protection with aim to minimize unnecessary exposure of the radiation protection personnel who deals with control, transport, radioactive waste treatment and decontamination. During exceptional operations (decontamination, repair, bigger volume of contaminated material, etc.) professional staff of the Radiation protection department gives recommendations and helps in planning the actions related to repair, sorting and packaging of radioactive waste in special containers, identification of the contaminants, etc. [sr

Radiation protection at the RA Reactor in 1998, Part 2, Annex 2, Decontamination and actions, collection of liquid effluents and solid radioactive waste

International Nuclear Information System (INIS)

Mandic, M.; Vukovic, Z.; Bacic, S.; Plecas, I.

1998-01-01

Certain amount of solid waste results from RA reactor operation, the mean quantity of which depends on the duration of reactor operation and related activities. During repair, when reactor is not operated as well under accidental conditions, the quantity of waste is higher, dependent on the type of repair and comprehensiveness of decontamination of the working surface, contaminated tools and components. The waste is sorted and packed on the spot where they appeared according to the existing regulations and principles of radiation protection with aim to minimize unnecessary exposure of the radiation protection personnel who deals with control, transport, radioactive waste treatment and decontamination. During exceptional operations (decontamination, repair, bigger volume of contaminated material, etc.) professional staff of the Radiation protection department gives recommendations and helps in planning the actions related to repair, sorting and packaging of radioactive waste in special containers, identification of the contaminants, etc. [sr

Analysis of radioactive contaminations and radiological hazard in Poland after the Chernobyl reactor accident

International Nuclear Information System (INIS)

Zarnowiecki, K.

1988-01-01

It is a report on radiological impact in Poland following the Chernobyl reactor accident prepared in the Central Laboratory for Radiological Protection. The results of measurement and its analysis are presented. Isotopic composition of the contamined air and the concentration of radionuclides are determined. The trajectories of the airborne radioactive material movement from Chernobyl to Poland at the last days of April 1986 are presented. Assessment of the radiological risk of the population is done. 38 refs., 20 figs., 11 tabs. (M.F.W.)

Radioactive tracer applications in the study of flow reactors. 4

International Nuclear Information System (INIS)

Thyn, J.; Hovorka, J.

1975-01-01

Response curves of gas streaming through the jet fluidized bed of a granular material in a rotary-jet pilot reactor were measured for a number of gas flow rates. A mathematical model of the gas residence time distribution was designed. Good agreement of the mathematical model with the experiments permits determining the ratio of streaming through the fluidized bed in form of bubbles of a different size. The measured values were evaluated as the distribution density of the gas residence time (age) at the outlet, the distribution function of the internal gas age in the device, and the so-called intensity function. The gas was labelled by a rapid injection of the radioactive 85 Kr and the response was studied by specially connected Geiger-Mueller counters placed inside the device, immediately above the granular material bed. (author)

Special Analysis for the Disposal of the INL Waste Associated with the Unirradiated Light Water Breeder Reactor (LWBR) Waste Stream at the Area 5 Radioactive Waste Management Site

Energy Technology Data Exchange (ETDEWEB)

Shott, Gregory [National Security Technologies, LLC, Las Vegas, NV (United States)

2017-03-21

This special analysis (SA) evaluates whether the Idaho National Laboratory (INL) Waste Associated with the Unirradiated Light Water Breeder Reactor (LWBR) waste stream (INEL167203QR1, Revision 0) is suitable for shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada National Security Site (NNSS). Disposal of the INL Waste Associated with the Unirradiated LWBR waste meets all U.S. Department of Energy (DOE) Manual DOE M 435.1-1, “Radioactive Waste Management Manual,” Chapter IV, Section P performance objectives (DOE 1999). The INL Waste Associated with the Unirradiated LWBR waste stream is recommended for acceptance with the condition that the total uranium-233 (²³3U) inventory be limited to 2.7E13 Bq (7.2E2 Ci).

Experience in radioactive waste management of research centre-CIAE

International Nuclear Information System (INIS)

Luo Shanggeng

2001-01-01

China Institute of Atomic Energy (CIAE) is the birthplace of China nuclear science and technology and the important base for nuclear science and technology implementing pioneering, basic and comprehensive studies. The major tasks and activities of CIAE are: (1) Fundamental research of nuclear science and technology; (2) Research and development of advanced nuclear energy; and (3) Application of nuclear technology. CIAE is equipped with three research reactors (15MW heavy water reactor, 3.5MW light water swimming pool reactor, 27kW neutron source reactor), four zero-power facilities, eleven accelerators, hot cells and a lot of glove boxes which produce various kinds of radioactive wastes. CIAE pays great attention to the safe management of radioactive waste. Many measurements were and are adopted. CIAE carries out the national policy of radioactive waste management and the international fundamental principles of radioactive waste management. To protect human body and environment both now and future generation minimizes the releasing amounts and activity, minimizes the solidified wastes to be disposed of. The principles of 'controlled generation, categorized collection, volume-reduction immobilization, reliable package, in-situ storage, safe transportation and disposal' are followed in managing LLW and ILW. The liquid wastes are separately treated by precipitation, evaporation, ion exchange or adsorption by organic or inorganic materials. The spent organic solvents are treated by incineration at a special incinerator. The low level radioactive gases and liquids can be discharged into the environment only when they are clean-up and permissible level is achieved. Such discharge is controlled by two factors: total discharge amount and specific activity. The solid wastes are separately collected in site according to their physical properties and specific activity. The storage waste is retrievable designed. The spent/sealed radiation sources are collected and stored with

Gamma-spectrometric and total alpha-beta counting methods for radioactivity analysis of deuterium depleted water

International Nuclear Information System (INIS)

Ferdes, Ov. S.; Mladin, C.; Vladu, Mihaela; Bulubasa, G.; Bidica, N.

2008-01-01

According to national regulations, as well as to the EU directive on the quality of drinking water, the radionuclide concentrations represent some of the drinking water quality parameters. Among the most important radioactivity content parameters are: the total alpha and total beta concentration (Bq/l); K-40 content, and the gamma-nuclides volume activities. The paper presents the measuring methods for low-level total alpha and/or beta counting of volume samples, as well as the high-resolution gamma-ray spectrometric method used to measure the volume activity of nuclides in drinking water. These methods are applied to monitor the radioactivity content and quality of the QLARIVIA brand of Deuterium depleted water (DDW). There are discussed the performances of these applied methods as well as some preliminary results. (authors)

Calculations of fuel burn up and radionuclide inventories in the Syrian miniature neutron source reactor using the WIMSD4 and CITATION codes

International Nuclear Information System (INIS)

Khattab, K.

2005-01-01

The WIMSD4 code is used to generate the fuel group constants and the infinite multiplication factor as a function of the reactor operating time for 10, 20, and 30 k W operating power levels. The uranium burn up rate and burn up percentage, the amounts of the plutonium isotopes, the concentrations and radioactivities of the fission products and actinide radionuclides accumulated in the reactor core, and the total radioactivity of the reactor core are calculated using the WIMSD4 code as well. The CITATION code is used to calculate the changes in the effective multiplication factor of the reactor.(author)

Cost of the radioactive residues of nuclear power

International Nuclear Information System (INIS)

1986-06-01

The calculation of cost for the management and final storage of spent nuclear fuel and radioactive waste is presented. The continuing Research and Development activities are judged to render simplified designs. The existing and planned systems and and plans are as follows: - transport system for radioactive residues - central intermediate storage of spent fuel, CLAB - processing of spent fuel - final storing of long-lived waste - final storing of reactor waste and decommissioning waste, SFR. The total future cost of the Swedish waste management is calculated to be 39 billion SEK from 1987 and 60 years onwards. 5.3 billion SEK have been spent up to the year 1986. (G.B.)

Management on radioactive wastes

International Nuclear Information System (INIS)

Balu, K.; Bhatia, S.C.

1979-01-01

The basic philosophy governing the radioactive waste management activities in India is to concentrate and contain as much activity as possible and to discharge to the environment only such of these streams that have radioactive content much below the nationally and internationally accepted standards. The concept of ''Zero Release'' is also kept in view. At Tarapur, the effluents are discharged into coastal waters after the radioactivity of the effluents is brought down by a factor 100. The effluents fΩm Rajasthan reactors are discharged into a lake keeping their radioactivity well within permissible limits and a solar evaporation plant is being set up. The plant, when it becomes operational, will be a step towards the concept of ''Zero Release''. At Kalpakkam, the treated wastes are proposed to be diluted by circulating sea water and discharged away from the shore through a long pipe. At Narora, ion exchange followed by chemical precipitation is to be employed to treat effluents and solar evaporation process for total containment. Solid wastes are stored/dispsed in the concrete trenches, underground with the water proofing of external surfaces and the top of the trench is covered with concrete. Highly active wastes are stored/disposed in tile holes which are vaults made of steel-lined, reinforced concrete pipes. Gas cleaning, dilution and dispersion techniques are adopted to treat gaseous radioactive wastes. (M.G.B.)

Management of the radioactive waste resulting from the Romanian VVR-S research reactor decommissioning

International Nuclear Information System (INIS)

Ene, D.; Cepraga, D.G.

2002-01-01

The paper consists in a waste study of the Romanian VVR-S reactor which will be prepared for decommissioning operations after the permanent shutdown (23.12.1997). Calculations were carried out to determine the activity arising from neutron activation of structural materials inside the reactor, considering the design of the facility and its operating rules. To this end, the following method was used: i) Neutron flux distribution within the reactor was calculated using the DORT transport code, based on DLC23 shielding library relating to three cylindrical reference systems of the reactor structure: reactor core, horizontal tube and thermal column; ii) Calculation of the activity of each reactor component at different cooling times was performed by the ANITA2000 code, using the neutron flux, compositional data for each material and the power history of the reactor; iii) Unconditional clearance indexes for all material at various cooling times were calculated using the clearance levels defined in IAEA-TECDOC-855; iv) Total activities and masses by material type, within the waste category and for each decay time were calculated by summation of the data previously classified for each reactor component. The resulting activation inventory and waste masses, falling in IAEA defined waste categories are presented in the paper at periods of 100 days, and 6, 10, 25, and 50 years after reactor the shutdown. For some components of the reactor as: aluminum central vessel, the central iron shielding ring, the time behaviour of both the fin spatial activity distribution and the radionuclide contributions to the total activity are plotted in the paper. (author)

Radioactive wastes in Oklo; Desechos radiactivos en Oklo

Energy Technology Data Exchange (ETDEWEB)

Balcazar, M.; Flores R, J.H.; Pena, P.; Lopez, A. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2006-07-01

The acceptance of the Nuclear Energy as electric power supply implies to give answer to the population on the two main challenges to conquer in the public opinion: the nuclear accidents and the radioactive wastes. Several of the questions that are made on the radioactive wastes, its are the mobility migration of them, the geologic stability of the place where its are deposited and the possible migration toward the aquifer mantels. Since the half lives of the radioactive waste of a Nuclear Reactor are of several hundred of thousands of years, the technical explanations to the previous questions little convince to the public in general. In this work summary the results of the radioactive waste generated in a natural reactor, denominated Oklo effect that took place in Gabon, Africa, it makes several thousands of millions of years, a lot before the man appeared in the Earth. The identification of at least 17 reactors in Oklo it was carried out thanks to the difference in the concentrations of Uranium 235 and 238 prospective, and to the analysis of the non-mobility of the radioactive waste in the site. It was able by this way to determine that the reactors with sizes of hardly some decimeter and powers of around 100 kilowatts were operating in intermittent and spontaneous form for space of 150,000 years, with operation cycles of around 30 minutes. Recent studies have contributed information valuable on the natural confinement of the radioactive waste of the Oklo reactors in matrixes of minerals of aluminum phosphate that caught and immobilized them for thousands of millions of years. This extracted information from the nature contributes guides and it allows 'to verify' the validity of the current proposals on the immobilization of radioactive wastes of a nuclear reactor. This work presents in clear and accessible form to the public in general on the secure 'design', operation, 'decommissioning' and 'storage' of the radioactive

Computed tomography of radioactive objects and materials

International Nuclear Information System (INIS)

Sawicka, B.D.; Murphy, R.V.; Tosello, G.; Reynolds, P.W.; Romaniszyn, T.

1990-01-01

Computed tomography (CT) has been performed on a number of radioactive objects and materials. Several unique technical problems are associated with CT of radioactive specimens. These include general safety considerations, techniques to reduce background-radiation effects on CT images and selection criteria for the CT source to permit object penetration and to reveal accurate values of material density. In the present paper, three groups of experiments will be described, for objects with low, medium and high levels of radioactivity. CT studies on radioactive specimens will be presented. They include the following: (1) examination of individual ceramic reactor-fuel (uranium dioxide) pellets, (2) examination of fuel samples from the Three Mile Island reactor, (3) examination of a CANDU (CANada Deuterium Uranium: registered trademark) nuclear-fuel bundle which underwent a simulated loss-of-coolant accident resulting in high-temperature damage and (4) examination of a PWR nuclear-reactor fuel assembly. (orig.)

Burn up calculations for the Iranian miniature reactor: A reliable and safe research reactor

International Nuclear Information System (INIS)

Faghihi, F.; Mirvakili, S.M.

2009-01-01

Presenting neutronic calculations pertaining to the Iranian miniature research reactor is the main goal of this article. This is a key to maintaining safe and reliable core operation. The following reactor core neutronic parameters were calculated: clean cold core excess reactivity (ρ ex ), control rod and shim worth, shut down margin (SDM), neutron flux distribution of the reactor core components, and reactivity feedback coefficients. Calculations for the fuel burnup and radionuclide inventory of the Iranian miniature neutron source reactor (MNSR), after 13 years of operational time, are carried out. Moreover, the amount of uranium burnup and produced plutonium, the concentrations and activities of the most important fission products, the actinide radionuclides accumulated, and the total radioactivity of the core are estimated. Flux distribution for both water and fuel temperature increases are calculated and changes of the central control rod position are investigated as well. Standard neutronic simulation codes WIMS-D4 and CITATION are employed for these studies. The input model was validated by the experimental data according to the final safety analysis report (FSAR) of the reactor. The total activity of the MNSR core is calculated including all radionuclides at the end of the core life and it is found to be equal to 1.3 x 10 3 Ci. Our investigation shows that the reactor is operating under safe and reliable conditions.

Burn up calculations for the Iranian miniature reactor: A reliable and safe research reactor

Energy Technology Data Exchange (ETDEWEB)

Faghihi, F. [Department of Nuclear Engineering, School of Engineering, Shiraz University, Shiraz 71345 (Iran, Islamic Republic of); Research Center for Radiation Protection, Shiraz University, Shiraz (Iran, Islamic Republic of)], E-mail: faghihif@shirazu.ac.ir; Mirvakili, S.M. [Department of Nuclear Engineering, School of Engineering, Shiraz University, Shiraz 71345 (Iran, Islamic Republic of)

2009-06-15

Presenting neutronic calculations pertaining to the Iranian miniature research reactor is the main goal of this article. This is a key to maintaining safe and reliable core operation. The following reactor core neutronic parameters were calculated: clean cold core excess reactivity ({rho}{sub ex}), control rod and shim worth, shut down margin (SDM), neutron flux distribution of the reactor core components, and reactivity feedback coefficients. Calculations for the fuel burnup and radionuclide inventory of the Iranian miniature neutron source reactor (MNSR), after 13 years of operational time, are carried out. Moreover, the amount of uranium burnup and produced plutonium, the concentrations and activities of the most important fission products, the actinide radionuclides accumulated, and the total radioactivity of the core are estimated. Flux distribution for both water and fuel temperature increases are calculated and changes of the central control rod position are investigated as well. Standard neutronic simulation codes WIMS-D4 and CITATION are employed for these studies. The input model was validated by the experimental data according to the final safety analysis report (FSAR) of the reactor. The total activity of the MNSR core is calculated including all radionuclides at the end of the core life and it is found to be equal to 1.3 x 10{sup 3}Ci. Our investigation shows that the reactor is operating under safe and reliable conditions.

Decommissioning strategy for reactor AM, Russian Federation

International Nuclear Information System (INIS)

Suvorov, A.P.; Mukhamadeev, R.I.

2002-01-01

This paper presents the results of studies into the various aspects of decommissioning the oldest Russian research reactor, the AM reactor. Experimental and calculation results of a study to determine the inventory of long lived radioactive materials at the AM reactor are presented, along with a comparison to comparable data for other similar reactors. An analysis, by calculation, of the decay time needed to allow manual dismantling of the reactor vessel and stack, without remote operated equipment, defined it as 90 years. The possibility of burning most of the irradiated graphite to decrease the amount of long lived radioactive wastes was confirmed. The problems associated with the dismantling of the reactor components, contaminated with radioactive corrosion products, were analyzed. A decommissioning strategy for reactor AM was formed which is deferred dismantling, placing most of the radiological areas into long term safe enclosure. An overall decommissioning plan for reactor AM is given. (author)

Low-level Radioactive waste Management

International Nuclear Information System (INIS)

1991-01-01

This meeting describes low-level radioactive waste management problems and contains 8 papers: 1 Low-level radioactive waste management: exemption concept and criteria used by international organizations. 2 Low-level radioactive waste management: french and foreign regulations 3 Low-level radioactive waste management in EDF nuclear power plants (FRANCE) 4 Low-level radioactive waste management in COGEMA (FRANCE) 5 Importance of low-level radioactive wastes in dismantling strategy in CEA (FRANCE) 6 Low-level radioactive waste management in hospitals 7 Low-level radioactive waste disposal: radiation protection laws 8 Methods of low-level radioactive materials measurements during reactor dismantling or nuclear facilities demolition (FRANCE)

Total Absorption Spectroscopy of Fission Fragments Relevant for Reactor Antineutrino Spectra and Decay Heat Calculations

Directory of Open Access Journals (Sweden)

Porta A.

2016-01-01

Full Text Available Beta decay of fission products is at the origin of decay heat and antineutrino emission in nuclear reactors. Decay heat represents about 7% of the reactor power during operation and strongly impacts reactor safety. Reactor antineutrino detection is used in several fundamental neutrino physics experiments and it can also be used for reactor monitoring and non-proliferation purposes. 92,93Rb are two fission products of importance in reactor antineutrino spectra and decay heat, but their β-decay properties are not well known. New measurements of 92,93Rb β-decay properties have been performed at the IGISOL facility (Jyväskylä, Finland using Total Absorption Spectroscopy (TAS. TAS is complementary to techniques based on Germanium detectors. It implies the use of a calorimeter to measure the total gamma intensity de-exciting each level in the daughter nucleus providing a direct measurement of the beta feeding. In these proceedings we present preliminary results for 93Rb, our measured beta feedings for 92Rb and we show the impact of these results on reactor antineutrino spectra and decay heat calculations.

Reactor safeguards

CERN Document Server

Russell, Charles R

1962-01-01

Reactor Safeguards provides information for all who are interested in the subject of reactor safeguards. Much of the material is descriptive although some sections are written for the engineer or physicist directly concerned with hazards analysis or site selection problems. The book opens with an introductory chapter on radiation hazards, the construction of nuclear reactors, safety issues, and the operation of nuclear reactors. This is followed by separate chapters that discuss radioactive materials, reactor kinetics, control and safety systems, containment, safety features for water reactor

Radiation protection at the RA Reactor in 1998, RA reactor annual report, Part -2

International Nuclear Information System (INIS)

Ninkovic, M.; Pavlovic, R.; Mandic, M.; Pavlovic, S.; Grsic, Z.

1998-01-01

Radiation protection tasks which enable safe operation of the RA reactor, and are defined according the the legal regulations and IAEA safety recommendations are sorted into four categories in this report: (1) Control of the working environment, dosimetry at the RA reactor; (2) Radioactivity control in the vicinity of the reactor and meteorology measurements; (3) Collecting and treatment of fluid effluents; and (4) radioactive wastes, decontamination and actions. Each of the category is described as a separate annex of this report [sr

Development of telerobotic systems for reactor decommissioning, (3)

International Nuclear Information System (INIS)

Usui, Hozumi; Fujii, Yoshio; Shinohara, Yoshikuni

1991-01-01

This paper describes the telerobotic system for reactor decommissioning in the scope of engineering demonstration of dismantling radioactive reactor internals of an experimental boiling water power reactor JPDR. The total system consists of a telerobotic manipulator system equipped with a multi-functional amphibious slave manipulator with a load capacity of 25 daN, a chain-driven transport system, and a computer-assisted monitoring and control system. Preceding to the application of the telerobotic system to actual dismantling operation, a mockup test was performed of dismantling the simulated reactor internals of actual-size by the method of underwater plasma arc cutting in order to study the performance of the telerobotic system in a realistic environment. The system was then successfully applied to dismantling the actual reactor internals according to the JPDR decommissioning program. (author)

Radiation protection at the RA Reactor in 1985, Part -2, Annex 2b, Environmental Radioactivity control, Control of air contamination

International Nuclear Information System (INIS)

Patic, D.; Smiljanic, R.; Zaric, M.; Savic, Z.; Ristic, D.

1985-01-01

During the period from November 1984 - November 1985, within the radioactivity control on the Vinca Institute site air contamination radioactive aerosol contents was measured. Control was done on 4 measuring stations, two in the Institute and two locations in the direction of wind i.e. Belgrade, 2 km and 7 km away from the Institute respectively. This position of the measuring locations enables control of radiation safety of the Institute, as well as environment of Belgrade taking into account the existence of the reactor and other possible contaminants in the Institute [sr

Radioactive effluent sources and special system of channels on the RA Reactor at the Boris Kidric Institute; Izvori radioaktivnih efluenata i specijalna kanalizacija u reaktoru RA Instituta Boris Kidric

Energy Technology Data Exchange (ETDEWEB)

Bojovic, P; Gacinovic, O; Milosevic, M [Institute of Nuclear Sciences Vinca, Beograd (Serbia and Montenegro)

1964-10-15

The paper describes the place of origin, composition and activity of radioactive effluents appearing in some reactor systems and special channels for carrying these effluents to disposal basins located outside the reactor building (author)

Immobilization of ion exchange radioactive resins of the TRIGA Mark III nuclear reactor

International Nuclear Information System (INIS)

Garcia M, H.; Emeterio H, M.; Canizal S, C.

1999-01-01

This work has the objective to develop the process and to define the agglutinating material which allows the immobilization of the ion exchange radioactive resins coming from the TRIGA Mark III nuclear reactor contaminated with Ba-133, Co-60, Cs-137, Eu-152, and Mn-54 through the behavior analysis of different immobilization agents such as: bitumens, cement and polyester resin. According to the International Standardization the archetype samples were observed with the following tests: determination of free liquid, leaching, charge resistance, biodegradation, irradiation, thermal cycle, burned resistance. Generally all the tests were satisfactorily achieved, for each agent. Therefore, the polyester resin could be considered as the main immobilizing. (Author)

Certifying the decommissioned Shippingport reactor vessel for transport

International Nuclear Information System (INIS)

Towell, R.H.

1990-01-01

The decommissioned Shippingport reactor pressure vessel with its concentric neutron shield tank was shipped to Hanford, WA as part of the effort to restore the Shippingport Station to its original condition. The metal walls of the reactor vessel had become radioactive from neutron bombardment while the reactor was operating so it had to be shipped under the regulations for transporting radioactive material. Because of the large amount of radioactivity in the walls, 16,467 Curies, and because the potentially dispersible corrosion layer on the inner walls of both tanks was also radioactive, the Shippingport reactor vessel was transported under the most stringent of the regulations, those for a type B package. Compliance with the packaging regulations was confirmed via independent analysis by the staff of the Department of Energy certifying official and the Shippingport reactor vessel was shipped under DOE Certificate of Compliance USA/9515/B(U)

Radioactive waste management from nuclear facilities

International Nuclear Information System (INIS)

2005-06-01

This report has been published as a NSA (Nuclear Systems Association, Japan) commentary series, No. 13, and documents the present status on management of radioactive wastes produced from nuclear facilities in Japan and other countries as well. Risks for radiation accidents coming from radioactive waste disposal and storage together with risks for reactor accidents from nuclear power plants are now causing public anxiety. This commentary concerns among all high-level radioactive waste management from nuclear fuel cycle facilities, with including radioactive wastes from research institutes or hospitals. Also included is wastes produced from reactor decommissioning. For low-level radioactive wastes, the wastes is reduced in volume, solidified, and removed to the sites of storage depending on their radioactivities. For high-level radioactive wastes, some ten thousand years must be necessary before the radioactivity decays to the natural level and protection against seismic or volcanic activities, and terrorist attacks is unavoidable for final disposals. This inevitably results in underground disposal at least 300 m below the ground. Various proposals for the disposal and management for this and their evaluation techniques are described in the present document. (S. Ohno)

Biological hazards of radioactivity and the biological consequences of radionuclide emissions from routine operation of nuclear power reactors

International Nuclear Information System (INIS)

Stendig-Lindberg, G.

1978-01-01

The biological hazards of radioactivity and the biological consequences of radionuclide emissions from the routine operation of nuclear power reactors are reviewed. ICRP and Scandinavian recommendations for the limitation of annual radiation doses are presented. The contribution of environmental conditions to radiation hazard is also discussed. It is concluded that a review of the justification of nuclear power is urgently needed. (H.K.)

Decommissioning of the Salaspils Research Reactor

Directory of Open Access Journals (Sweden)

Abramenkovs Andris

2011-01-01

Full Text Available In May 1995, the Latvian government decided to shut down the Salaspils Research Reactor and to dispense with nuclear energy in the future. The reactor has been out of operation since July 1998. A conceptual study on the decommissioning of the Salaspils Research Reactor was drawn up by Noell-KRC-Energie- und Umwelttechnik GmbH in 1998-1999. On October 26th, 1999, the Latvian government decided to start the direct dismantling to “green-field” in 2001. The upgrading of the decommissioning and dismantling plan was carried out from 2003-2004, resulting in a change of the primary goal of decommissioning. Collecting and conditioning of “historical” radioactive wastes from different storages outside and inside the reactor hall became the primary goal. All radioactive materials (more than 96 tons were conditioned for disposal in concrete containers at the radioactive wastes depository “Radons” at the Baldone site. Protective and radiation measurement equipment of the personnel was upgraded significantly. All non-radioactive equipment and materials outside the reactor buildings were released for clearance and dismantled for reuse or conventional disposal. Contaminated materials from the reactor hall were collected and removed for clearance measurements on a weekly basis.

Nuclear Reactor RA Safety Report, Vol. 8, Auxiliary system

International Nuclear Information System (INIS)

1986-11-01

This volume describes RA reactor auxiliary systems, as follows: special ventilation system, special drainage system, hot cells, systems for internal transport. Ventilation system is considered as part of the reactor safety and protection system. Its role is eliminate possible radioactive particles dispersion in the environment. Special drainage system includes pipes and reservoirs with the safety role, meaning absorption or storage of possible radioactive waste water from the reactor building. Hot cells existing in the RA reactor building are designed for production of sealed radioactive sources, including packaging and transport [sr

Application of radiological imaging methods to radioactive waste characterization

Energy Technology Data Exchange (ETDEWEB)

Tessaro, Ana Paula Gimenes; Souza, Daiane Cristini B. de; Vicente, Roberto, E-mail: aptessaro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

Radiological imaging technologies are most frequently used for medical diagnostic purposes but are also useful in materials characterization and other non-medical applications in research and industry. The characterization of radioactive waste packages or waste samples can also benefit from these techniques. In this paper, the application of some imaging methods is examined for the physical characterization of radioactive wastes constituted by spent ion-exchange resins and activated charcoal beds stored at the Radioactive Waste Management Department of IPEN. These wastes are generated when the filter media of the water polishing system of the IEA-R1 Nuclear Research Reactor is no longer able to maintain the required water quality and are replaced. The IEA-R1 is a 5MW pool-type reactor, moderated and cooled by light water, and fission and activation products released from the reactor core must be continuously removed to prevent activity buildup in the water. The replacement of the sorbents is carried out by pumping from the filter tanks into several 200 L drums, each drum getting a variable amount of water. Considering that the results of radioanalytical methods to determine the concentrations of radionuclides are usually expressed on dry basis,the amount of water must be known to calculate the total activity of each package. At first sight this is a trivial problem that demanded, however some effort to be solved. The findings on this subject are reported in this paper. (author)

Nuclear reactor container

International Nuclear Information System (INIS)

Yamaki, Rika; Kawabe, Ryuhei.

1989-01-01

A venturi scrubber is connected to a nuclear reactor container. Gases containing radioactive aerosols in the container are introduced into the venturi scrubber in the form of a high speed stream under the pressure of the container. The radioactive aerosols are captured by inertia collision due to the velocity difference between the high speed gas stream and water droplets. In the case of the present invention, since the high pressure of the reactor container generated upon accident is utilized, compressor, etc. is no more required, thereby enabling to reduce the size of the aerosol removing device. Further, since no external power is used, the radioactive aerosols can be removed with no starting failure upon accidents. (T.M.)

Proposal of the concept of selection of accidents that release large amounts of radioactive substances in the high temperature engineering test reactor

International Nuclear Information System (INIS)

Ono, Masato; Honda, Yuki; Takada, Shoji; Sawa, Kazuhiro

2015-01-01

In Position, construction and equipment of testing and research reactor to be subjected to the use standards for rules Article 53 (prevention of expansion of the accident to release a large amount of radioactive material) generation the frequency is a lower accident than design basis accident, when what is likely to release a large amount of radioactive material or radiation from the facility has occurred, and take the necessary measures in order to prevent the spread of the accident. There is provided a lower accident than frequency design basis accidents, for those that may release a large amount of radioactive material or radiation. (author)

Method to determine the activity concentration and total activity of radioactive waste; Metodo para determinar la concentracion de actividad y actividad total de desechos radiactivos

Energy Technology Data Exchange (ETDEWEB)

Angeles C, A

2001-02-15

A characteristic system of radioactive waste is described to determine the concentration of radionuclides activity and the total activity of bundles of radioactive waste. The system this integrated by three subsystems: - Elevator of drums. - Electromechanics. - Gamma spectroscopy. In the system it is analyzed waste of issuing gamma specifically, and this designed for materials of relative low density and it analyzes materials of cylindrical recipients.

Contamination of the air and other environmental samples of the Ulm region by radioactive fission products after the accident of the Chernobyl reactor

International Nuclear Information System (INIS)

Krivan, V.; Egger, K.P.; Hausbeck, R.; Schmid, W.

1986-01-01

Since April 30, 1986, the radioactivity of the fission products released by the accident of the Chernobyl reactor has been measured in the air of the city of Ulm. The airborne dust samples were collected with flow calibrated samplers on cellulose acetate membrane filters and counted with a high resolution gamma ray spectrometer. Later on, the radioactivity measurements were expanded to other relevant environmental samples contaminated by radioactive atmospheric precipitates including grass, spruce needles, mosses, lichens, various kinds of food, drinking water, asphalt and concrete surface layers, municipal sewage sludge and sewage sludge ash. This paper reports the obtained results. (orig.) [de

JANUS reactor d and d project

International Nuclear Information System (INIS)

Fellhauer, C. R.

1998-01-01

Argonne National Laboratory (ANL-E) has recently completed the decontamination and decommissioning (D and D) of the JANUS Reactor Facility located in Building 202. The 200 KW reactor operated from August 1963 to March 1992. The facility was used to study the effects of both high and low doses of fission neutrons in animals. There were two exposure rooms on opposite sides of the reactor and the reactor was therefore named after the two-faced Roman god. The High Dose Room was capable of specimen exposure at a dose rate of 3,600 rads per hour. During calendar year 1996 a detailed characterization of the facility was performed by ANL-E Health Physics personnel. ANL-E Analytical Services performed the required sample analysis. An Auditable Safety Analysis and an Environmental Assessment were completed. D and D plans, procedures and procurement documents were prepared and approved. A D and D subcontractor was selected and a firm, fixed price contract awarded for the field work and final survey effort. The D and D subcontractor was mobilized to ANL-E in January 1997. Electrical isolation of all reactor equipment and control panels was accomplished and the equipment removed. A total of 207,230 pounds (94,082 Kg) of lead shielding was removed, surveyed and sampled, and free-released for recycle. All primary and secondary piping was removed, size reduced and packaged for disposal or recycled as appropriate. The reactor vessel was removed, sized reduced and packaged as radioactive waste in April. The activated graphite block reflector was removed next, followed by the bioshield concrete and steel. All of this material was packaged as low level waste. Total low level radioactive waste generation was 4002.1 cubic feet (113.3 cubic meters). Mixed waste generation was 538 cubic feet (15.2 cubic meters). The Final Release Survey was completed in September. The project field work was completed in 38 weeks without any lost-time accidents, personnel contaminations or unplanned

Environmental radioactivity in Canada, 1981

International Nuclear Information System (INIS)

McGregor, R.G.; Quinn, J.M.; Tracy, B.L.

1983-01-01

The radiological surveillance program of the Department of National Health and Welfare is conducted for the purpose of determining levels of environmental radioactivity in Canada and assessing the resulting population exposures. Special investigations were carried out during 1981 on bottled mineral waters and in conjunction with unusual occurences at nuclear reactor sites and a uranium refinery. Dose commitments have been estimated for the ongoing natural radioactivity, fallout and reactor studies. All measurements made during the year are below the limits recommended by the International Commission on Radiological Protection

1: the atom. 2: radioactivity. 3: man and radiations. 4: the energy. 5: nuclear energy: fusion and fission. 6: the operation of a nuclear reactor. 7: the nuclear fuel cycle

International Nuclear Information System (INIS)

2002-01-01

This series of 7 digest booklets present the bases of the nuclear physics and of the nuclear energy: 1 - the atom (structure of matter, chemical elements and isotopes, the four fundamental interactions, nuclear physics); 2 - radioactivity (definition, origins of radioelements, applications of radioactivity); 3 - man and radiations (radiations diversity, biological effects, radioprotection, examples of radiation applications); 4 - energy (energy states, different forms of energy, characteristics); 5 - nuclear energy: fusion and fission (nuclear energy release, thermonuclear fusion, nuclear fission and chain reaction); 6 - operation of a nuclear reactor (nuclear fission, reactor components, reactor types); 7 - nuclear fuel cycle (nuclear fuel preparation, fuel consumption, reprocessing, wastes management). (J.S.)

Radioactive corrosion products in circuit of fast reactor loop with dissociating coolant

International Nuclear Information System (INIS)

Dolgov, V.M.; Katanaev, A.O.

1982-01-01

The results of experimental investigation into depositions of radionuclides of corrosion origin on the surfaces of a reactor-in-pile loop facility with a dissociating coolant are presented. It is stated that the ratio of radionuclides in fixed depositions linearly decreases with decrease of the coolant temperature at the core-condenser section. The element composition of non-fixed compositions quantitatively and qualitatively differs from the composition of structural material, and it is more vividly displayed for the core-condenser section. The main mechanism of circuit contamination with radioactive corrosion products is substantiated: material corrosion in the zones of coolant phase transfer, their remove by the coolant in the core, deposition, activation and wash-out by the coolant from the core surfaces

Perspectives concerning radioactive waste management

International Nuclear Information System (INIS)

Noynaert, L.

2013-01-01

The article presents a general overview of the principles of radioactive waste management as established by the International Atomic Energy Agency. Subsequently, research and development related to radioactive waste management at the Belgian Nuclear Research Center SCK·CEN is discussed. Different topical areas are treated including radioactive waste characterisation, decontamination and the long-term management of radioactive waste. The decommissioning of the BR3 reactor and the construction and the exploitation of the underground research laboratory HADES are cited as examples of the pioneering role that SCK·CEN has played in radioactive waste management.

Radioactive waste management at a Liquid Metal Fast Breeder Reactor

International Nuclear Information System (INIS)

Abrams, C.S.; Fryer, R.H.; Witbeck, L.C.

1979-01-01

This paper presents the radioactive waste production and management at a Liquid Metal Fast Breeder Reactor-II (EBR-II), which is operated for the US Department of Energy by the Argonne National Laboratory at the Idaho National Engineering Laboratory (INEL). Since this facility, in addition to supplying power has been used to demonstrate the breeder, fuel cycling, and recently operations with defective fuel elements, various categories of waste have been handled safely over some 14 years of operation. Liquid wastes are processed such that the resulting effluent can be discharged to an uncontrolled area. Solid wastes up to 10,000 R/hr are packaged and shipped contamination-free to a disposal site or interim storage with exposures to personnel approximately 10 mrem. Gaseous waste discharges are low such as 143 Ci of noble gases in 1978 and do not have a significant effect on the environment even with operations with breached fuel

Radioactive pollution

International Nuclear Information System (INIS)

Steiner, R.

1987-01-01

In the wake of the Chernobyl reactor accident on April 26, 1986, many individual values for radioactivity in the air, in foodstuffs and in the soil were measured and published. Prof. Dr. Rolf Steiner, Wiesbaden, the author of this paper, evaluated the host of data - mostly official pollution data -, drew conclusions regarding the radioactivity actually released at Chernobyl, and used the data to test the calculation model adotped by the Radiation Protection Ordinance. (orig./RB) [de

Ventilation method and device for nuclear reactor

International Nuclear Information System (INIS)

Nakamura, Hideki; Ono, Kiyoshi; Ohara, Atsushi.

1997-01-01

In a BWR type reactor, a device for removing radioactive materials is disposed on the midway of a vent pipeline in order to prevent pressurization failure caused by elevation of pressure in the reactor container. Namely, when the pressure in the reactor container is released, particulate or gaseous radioactive materials are led from an extraction gas of a main condensator to a gaseous waste processing system through the vent pipeline, and then radioactive materials are removed by the gaseous waste processing system, and led to a gas exhaustion cylinder. In addition, as a countermeasure for a severe accident, one end of the vent pipeline having the other end opened to a dry well and a wet well of a reactor container is connected upstream of an exhausted gas condensator of the gaseous waste processing system. This can prevent the failure of the reactor container upon occurrence of a severe accident, and the release of radioactive materials to the atmosphere can be greatly reduced without disposing a large-scaled removing device. (N.H.)

Guidelines for calculating radiation doses to the public from a release of airborne radioactive material under hypothetical accident conditions in nuclear reactors

International Nuclear Information System (INIS)

1991-04-01

This standard provides guidelines and a methodology for calculating effective doses and thyroid doses to people (either individually or collectively) in the path of airborne radioactive material released from a nuclear facility following a hypothetical accident. The radionuclides considered are those associated with substances having the greatest potential for becoming airborne in reactor accidents: tritium (HTO), noble gases and their daughters, radioiodines, and certain radioactive particulates (Cs, Ru, Sr, Te). The standard focuses on the calculation of radiation doses for external exposures from radioactive material in the cloud; internal exposures for inhalation of radioactive material in the cloud and skin penetration of tritium; and external exposures from radionuclides deposited on the ground. It uses as modified Gaussian plume model to evaluate the time-integrated concentration downwind. (52 refs., 12 tabs., 21 figs.)

Storage of solid and liquid radioactive material

International Nuclear Information System (INIS)

Matijasic, A.; Gacinovic, O.

1961-01-01

Solid radioactive waste collected during 1961 from the laboratories of the Institute amounted to 22.5 m 3 . This report contains data about activity of the waste collected from january to November 1961. About 70% of the waste are short lived radioactive material. Material was packed in metal barrels and stored in the radioactive storage in the Institute. There was no contamination of the personnel involved in these actions. Liquid radioactive wastes come from the Isotope production laboratory, laboratories using tracer techniques, reactor cooling; decontamination of the equipment. Liquid wastes from isotope production were collected in plastic bottles and stored. Waste water from the RA reactor were collected in special containers. After activity measurements this water was released into the sewage system since no activity was found. Table containing data on quantities and activity of radioactive effluents is included in this report

Cask for radioactive material and method for preventing release of neutrons from radioactive material

International Nuclear Information System (INIS)

Gaffney, M.F.; Shaffer, P.T.

1981-01-01

A cask for radioactive material, such as nuclear reactor fuel or spent nuclear reactor fuel, includes a plurality of associated walled internal compartments for containing such radioactive material, with neutron absorbing material present to absorb neutrons emitted by the radioactive material, and a plurality of thermally conductive members, such as longitudinal copper or aluminum castings, about the compartment and in thermal contact with the compartment walls and with other such thermally conductive members and having thermal contact surfaces between such members extending, preferably radially, from the compartment walls to external surfaces of the thermally conductive members, which surfaces are preferably in the form of a cylinder. The ends of the shipping cask also preferably include a neutron absorber and a conductive metal covering to dissipate heat released by decay of the radioactive material. A preferred neutron absorber utilized is boron carbide, preferably as plasma sprayed with metal powder or as particles in a matrix of phenolic polymer, and the compartment walls are preferably of stainless steel, copper or other corrosion resistant and heat conductive metal or alloy. The invention also relates to shipping casks, storage casks and other containers for radioactive materials in which a plurality of internal compartments for such material, e.g., nuclear reactor fuel rods, are joined together, preferably in modular construction with surrounding heat conductive metal members, and the modules are joined together to form a major part of a finished shipping cask, which is preferably of cylindrical shape. Also within the invention are methods of safely storing radioactive materials which emit neutrons, while dissipating the heat thereof, and of manufacturing the present shipping casks

Radiologic states of the WWR-S Bucharest Reactor following definitive shutdown

International Nuclear Information System (INIS)

Garlea, C.; Kelerman, C.; Mocioiu, D.; Garlea, I.

2001-01-01

The definitive shutdown of a reactor raises problems related to the management of the radioactive inventory. To define the radioactive inventory contained in the burned nuclear fuel and in the neutron activated structural materials computation methods are to be used. Besides the radioactive inventory contained in the main block of the reactor, the one due to the primary circuit contaminated mainly with fission products and corrosion products activated in the reactor core, transported and deposed on the components of the cooling primary circuit should be added. Also another component of the radioactive inventory intervenes, namely, the one due to the contamination of the technological rooms used for various operations the nuclear activities (hot cells, pump room, reactor hall, passage ways to the hot cells and for radioactive source, radioisotope and radioactive waste transport). The activities which made used of the neutron and gamma fluxes for radioisotope production, materials irradiation, research, component testing, resulted in radioactive waste, technological or accidental contaminations of the technological rooms of the reactor. Inspections and current repair interventions resulted also in radioactive waste an contaminations. Consequently systematic measurements with qualified equipment dedicated to alpha, beta, gamma contamination measurements as well as to dose rates determinations for the personnel exposed are necessary. Irrespective of the duration of the reactor conservation or shutdown, the radiologic monitoring should continue. This work presents the results obtained by the research group 'Restoration of Nuclear Sites', working with the IFIN-HH, regarding both the radioactive inventory calculation and measurements of contamination of technological rooms and environment in the reactor vicinity

Old and new ways in reactor technology. Reactor concepts and reactor safety

Energy Technology Data Exchange (ETDEWEB)

Schulten, R

1989-01-01

Compared to developments of other technical-scale systems, the period between the recognition of the underlying physics of nuclear fission and the development of a functioning nuclear reactor and its further development to the present level of maturity has been relatively short. The whole development is based on the chain reaction and is rendered safe by the possible auto-stabilization of this reaction. Consequently, the safety of nuclear reactors properly designed is based on automatic mechanisms, which prevent spreads of radioactivity even in major accidents. Controversial opinions about nuclear power uses are mostly based on wrong perceptions both of reactor safety and of radioactive waste, unless they are characterized by sheer ideology. The use of nuclear power worldwide has assumed an important, growing role in the combined uses of a variety energy sources in a surprisingly short period of time and will continue to make a safe, economic, and thus responsible contribution in the long run.

Coolant cleaning facility for nuclear reactor

International Nuclear Information System (INIS)

Kuboniwa, Takao; Konno, Yasuhiro; Kumaya, Shin; Osumi, Katsumi.

1982-01-01

Purpose: To remove cation of radioactive cobalt 60 produced in a reactor water during the ordinary operation of the reactor and chlorine when sea water is leaked in a condenser as well as to suppress an increase in iron clad containing radioactive cobalt 60 in the reactor water when the reactor is stopped. Constitution: A large flow rate high temperature cleaning system having an electromagnetic filter capable of removing radioactive substance in a reactor water, a low temperature cleaning system having a desalting unit using ion exchanger resin, a turbidity meter for measuring the turbidity of the reactor water and a conductivity meter for measuring the conductivity are provided. Further, flow rate control means are provided in the high and low temperature cleaning systems. The flow rate control means of the high temperature cleaning system is controlled by a measured signal of the turbidity meter, and the flow rete control means of the low temperature cleaning system is controlled by the measured signal of the conductivity meter. (Aizawa, K.)

PLAN 98 - Costs for management of the radioactive waste from nuclear power production

International Nuclear Information System (INIS)

1998-06-01

The nuclear utilities in Sweden are responsible for managing and disposing of spent nuclear fuel and radioactive waste from the nuclear power reactors in a safe manner. The most important measures are to plan, build and operate the facilities and systems needed, and to conduct related R and D. This report presents a calculation of the costs for implementing all of these measures. The following facilities and systems are in operation: Transportation system for radioactive waste products. Central interim storage facility for spent nuclear fuel, CLAB. Final repository for radioactive operational waste, SFR I. Plans also exist for: Encapsulation plant for spent nuclear fuel. Deep repository for spent fuel and other long-lived waste. Final repository for decommissioning waste. The cost calculations also include costs for research, development and demonstration, as well as for decommissioning and dismantling the reactor plants etc. At the end of 1995, certain amendments were made in the Financing Act which influence the calculations presented in this report. The most important amendment is that the reactor owners, besides paying a fee or charge on nuclear energy production, must also give guarantees as security for remaining costs. In this way the fee can be based on a probable cost for waste management. This cost includes uncertainties and variations that are normal for this type of project. Cost increases as a consequence of major changes, disruptions etc. can instead be covered via the given guarantees. The total future costs, in January 1998 prices, for the Swedish waste management system from 1999 onward has been calculated to be SEK 45.8 billion. The total costs apply for the waste obtained from 25 years of operation of all Swedish reactors. They will fall due over a total period of approximately 50 years up to the middle of the 2l st century, but the greater part will fall due during the next 20 years. It is estimated that SEK 12.1 billion in current money terms

Reactor safety study. An assessment of accident risks in U.S. commercial nuclear power plants. Appendix VI. Calculation of reactor accident consequences

International Nuclear Information System (INIS)

1975-10-01

Information is presented concerning the radioactive releases from the containment following accidents; radioactive inventory of the reactor core; atmospheric dispersion; reactor sites and meteorological data; radioactive decay and deposition from plumes; finite distance of plume travel; dosimetric models; health effects; demographic data; mitigation of radiation exposure; economic model; and calculated results with consequence model

Characterization and management of radioactive sodium and other reactor components as input data for the decommissioning of liquid metal-cooled fast reactors. A compilation of data produced of data produced by members of the IAEA technical working group on fast reactors (TWG-FR) at two consultancies and one technical committee meeting. Working material

International Nuclear Information System (INIS)

2002-01-01

A number of liquid metal cooled fast reactors (LMFRs) are in operation and, some have already been shut down; other reactors will reach the end of their design lifetime in a few years and become candidates for decommissioning. It is unfortunate that little consideration was devoted to decommissioning of reactors at the plant design and construction stage. It is with this focus that the Technical Working Group on Fast Reactors (TWGFR) recommended that the IAEA organize the exchange of information on LMFRs decommissioning technology. It was pointed out that the decommissioning of small sodium-cooled reactors has shown that there are two basic differences between thermal and fast reactors decommissioning: on the one side, the treatment and disposal of radioactive sodium coolant, and on the other side, the management of reactor components, for which the structural materials are activated in depth by fast neutrons. To this end, a Technical Committee Meeting on Sodium Removal and Disposal from LMFRs in Normal Operation and in the framework of Decommissioning (Aix-en-Provence, France, November 1997) and two Consultancies on Decommissioning of the Kazakh BN-350 LMFR (Vienna, Austria, October 1996; Obninsk, Russian Federation, February 1998) were convened by the IAEA. These Meetings brought together a group of experts from France, Russia, Kazakhstan, the UK, and the USA to exchange information on, and to review current technical knowledge and experience in the management of radioactive coolant and reactor components following closing of LMFRs, as well as their design features and operating experience relevant for decommissioning procedures. The report provides general and detailed information on activation characteristics of the primary coolant; treatment and disposal of the spent sodium; removal of the residual sodium deposits and decontamination; the activation characteristics of the reactor components and the management of the latter. The recurring theme is finding

Radioactive releases into the environment under accidental conditions

International Nuclear Information System (INIS)

Beninson, D.

1976-01-01

Although accidents involving the release of radioactive materials and the unplanned exposure of people can occur at any stage of the nuclear fuel cycle, most attention has been focused on reactor accidents. Although no power reactor accidents involving exposure of the public have yet occured, it should be recognized that the probability of such accidental releases cannot be reduced to zero. Since the inventory of radioactive materials in power reactors is very large, it is usual to postulate, for safety assessments, that a release of fission products takes place in spite of all protective measures. This postulated release is of importance for reactor siting and for preparing emergency plans. (HP) [de

Development of radioactive stent using HANARO research reactor

Energy Technology Data Exchange (ETDEWEB)

Park, Kyung Bae; Kim, J. R.; Han, H. S.; Shin, B. C.; Kim, Y. M.; Cho, U. K.; Han, K. H.; Park, W. W.; Chung, Y. J

1997-10-01

Radioactive cylindrical was prepared by neutron irradiation of pre-made non-radioactive `1`6`5 Ho-sleeve, which was made by casting polyurethane solution containing `1`6`5`Ho(NO{sub 3}){sub 3} in THF+DMF (10:1) solvent in cylindrical glass tube. Its length and diameter could be easily controlled by glass tube used as a mold. The radioactive stent assembly (`1`6`5Ho-SA) was prepared by covering the metallic stent with radioactive sleeve and then treated both ends with epoxy glue for prevention of peeling off the radioactive sleeve from stent (post-irradiation method). Other preparation method of radioactive stent is similar to that of the first one except using radioactive `1`6`6Ho(NO{sub 3}){sub 3} and glass tube fitted with metallic stent before casting (pre-irradiation method). Scanning electron microscopy and autoradiography exhibited that the distribution of `1`6`5Ho and `1`6`6Ho(NO{sub 3}) compounds in polyurethane matrix was nearly homogeneous. The present preparation methods of radioactive sleeve and stent are quite different from conventional method which metallic stent is coated or implanted with radionuclide. The ease with which the radioactive stent can be prepared and its homogeneous radiation emission make it an attractive radiation applicator for the treatment of esophagus cancer. As an animal studies, 6 pathologic specimens were obtained. An animal with 4 mCi of `1`6`6Ho-SA showed loss of epithelial tissue and inflammation at the submucosal layer 4 weeks after the procedure. Considerable improvement of the inflammatory reaction was observed 7 weeks post-therapy without complication. In case treated with 6 mCi of `1`6`6Ho-SA, tissue destruction and widening of the esophageal lumen were observed and the inflammatory reaction propagated into the muscle layer. In case with 9 mCi of `1`6`6Ho-SA, severe esophagitis with cellular proliferation were seen, which resulted in further narrowing of the lumen. (author). 58 refs., 5 tabs., 14 figs

Development of radioactive stent using HANARO research reactor

International Nuclear Information System (INIS)

Park, Kyung Bae; Kim, J. R.; Han, H. S.; Shin, B. C.; Kim, Y. M.; Cho, U. K.; Han, K. H.; Park, W. W.; Chung, Y. J.

1997-10-01

Radioactive cylindrical was prepared by neutron irradiation of pre-made non-radioactive '1'6'5 Ho-sleeve, which was made by casting polyurethane solution containing '1'6'5'Ho(NO 3 ) 3 in THF+DMF (10:1) solvent in cylindrical glass tube. Its length and diameter could be easily controlled by glass tube used as a mold. The radioactive stent assembly ('1'6'5Ho-SA) was prepared by covering the metallic stent with radioactive sleeve and then treated both ends with epoxy glue for prevention of peeling off the radioactive sleeve from stent (post-irradiation method). Other preparation method of radioactive stent is similar to that of the first one except using radioactive '1'6'6Ho(NO 3 ) 3 and glass tube fitted with metallic stent before casting (pre-irradiation method). Scanning electron microscopy and autoradiography exhibited that the distribution of '1'6'5Ho and '1'6'6Ho(NO 3 ) compounds in polyurethane matrix was nearly homogeneous. The present preparation methods of radioactive sleeve and stent are quite different from conventional method which metallic stent is coated or implanted with radionuclide. The ease with which the radioactive stent can be prepared and its homogeneous radiation emission make it an attractive radiation applicator for the treatment of esophagus cancer. As an animal studies, 6 pathologic specimens were obtained. An animal with 4 mCi of '1'6'6Ho-SA showed loss of epithelial tissue and inflammation at the submucosal layer 4 weeks after the procedure. Considerable improvement of the inflammatory reaction was observed 7 weeks post-therapy without complication. In case treated with 6 mCi of '1'6'6Ho-SA, tissue destruction and widening of the esophageal lumen were observed and the inflammatory reaction propagated into the muscle layer. In case with 9 mCi of '1'6'6Ho-SA, severe esophagitis with cellular proliferation were seen, which resulted in further narrowing of the lumen. (author). 58 refs., 5 tabs., 14 figs

Monitoring of gross beta radioactivities on water sample environment in the surrounding of kartini reactor at 2011

International Nuclear Information System (INIS)

Siswanti; Munandar, A. Aris

2013-01-01

Measurement of gross beta radioactivities on water environment were done in the PTAPB BATAN has a goal for routine monitoring, with the result that fill RPL has been made and the result equivalented with quality standard were decided by BAPETEN. The water sample taken as much as 2 liter at 18 area were definited on radius 100 m to 5000 m in the surrounding of kartini reactor, vaporin on electric stove till the volume been ± 10 ml, and than pick out to the aluminium planset and drying on hot plate. Sample in the plancet were counted with a Low Background Counter (LBC) for 30 minutes and accounted of gross beta radioactivity water system. The result of gross beta radioactivity water environment at 2011 has a lowest 009, ± 0,06 Bq/I on Tambak Bayan area at june and in the Janti area highest 0,39 ± 0,08 Bq/ at December. The result still under of quality standard were decided by SK BAPETEN. No. 02/Ka- BAPETEN/V-99 is 0,4 Bq/I. (author)

Radioactivity measurements of water, milk and dairy products, vegetables and grass from the surroundings of Cracow on the aftermath of Chernobyl reactor accident

International Nuclear Information System (INIS)

Cywicka-Jakiel, T.; Grychowski, P.; Hajdas, I.; Jasinska, M.; Kolakowski, L.; Loskiewicz, L.; Mazgaj, Z.; Mikulski, J.; Ochab, E.

2004-01-01

The measurements of radioactive contamination of water and food products were carried out shortly after the Chernobyl nuclear reactor accident. Using the measured values, the committed effective dose equivalent for adult population of Cracow was estimated. (author)

Actions to reduce radioactive emissions: prevention of containment failure by flooding Containment and Reactor Cavity; Acciones para la reduccion de emisiones radiactivas: prevencion del fallo de la Contencion mediante la inundacion de la Contencion y de la Cavidad del Reactor

Energy Technology Data Exchange (ETDEWEB)

Fornos Herrando, J.

2013-07-01

The reactor cavity of Asco and Vandellos II is dry type, thus a severe accident leading to vessel failure might potentially end up resulting in the loss of containment integrity, depending on the viability to cool the molten core. Therefore, significant radioactive emissions could be released to outside. In the framework of Fukushima Stress Tests, ANAV has analyzed the convenience of carrying out different actions to prevent failure of the containment integrity in order to reduce radioactive emissions. The aim of this paper is to present and describe the main phenomenological aspects associated with two of these actions: containment flooding and reactor cavity flooding.

Current issues in the management of low- and intermediate-level radioactive wastes from Ontario Hydro's CANDU reactors

International Nuclear Information System (INIS)

Krasznai, J.P.; Vaughan, B.R.; Williamson, A.S.

1990-01-01

Nuclear generating stations (NGSs) in Canada are operated by utilities in Ontario, Quebec, and New Brunswick. Ontario Hydro, with a committed nuclear program of 13,600 MW(electric) is the major producer of CANDU pressurized heavy-water reactor (PHWR) low- and intermediate-level radioactive wastes. All radioactive wastes with the exception of irradiated fuel are processed and retrievably stored at a centralized facility at the Bruce Nuclear Power Development site. Solid-waste classifications and annual production levels are given. Solid-waste management practices at the site as well as the physical, chemical, and radiochemical characteristics of the wastes are well documented. The paper summarizes types, current inventory, and estimated annual production rate of liquid waste. Operation of the tritium recovery facility at Darlington NGS, which removes tritium from heavy water and produces tritium gas in the process, gives rise to secondary streams of tritiated solid and liquid wastes, which will receive special treatment and packaging. In addition to the treatment of radioactive liquid wastes, there are a number of other important issues in low- and intermediate-level radioactive waste management that Ontario Hydro will be addressing over the next few years. The most pressing of these is the reduction of radioactive wastes through in-station material control, employee awareness, and improved waste characterization and segregation programs. Since Ontario Hydro intends to store retrievable wastes for > 50 yr, it is necessary to determine the behavior of wastes under long-term storage conditions

Principle of natural and artificial radioactive series equivalency

International Nuclear Information System (INIS)

Vasilyeva, A.N.; Starkov, O.V.

2001-01-01

In the present paper one approach used under development of radioactive waste management conception is under consideration. This approach is based on the principle of natural and artificial radioactive series radiotoxic equivalency. The radioactivity of natural and artificial radioactive series has been calculated for 10 9 - years period. The toxicity evaluation for natural and artificial series has also been made. The correlation between natural radioactive series and their predecessors - actinides produced in thermal and fast reactors - has been considered. It has been shown that systematized reactor series data had great scientific significance and the principle of differential calculation of radiotoxicity was necessary to realize long-lived radioactive waste and uranium and thorium ore radiotoxicity equivalency conception. The calculations show that the execution of equivalency principle is possible for uranium series (4n+2, 4n+1). It is a problem for thorium. series. This principle is impracticable for neptunium series. (author)

Separation of non-hazardous, non-radioactive components from ICPP calcine via chlorination

International Nuclear Information System (INIS)

Nelson, L.O.

1995-05-01

A pyrochemical treatment method for separating non-radioactive from radioactive components in solid granular waste accumulated at the Idaho Chemical Processing Plant was investigated. The goal of this study was to obtain kinetic and chemical separation data on the reaction products of the chlorination of the solid waste, known as calcine. Thermodynamic equilibrium calculations were completed to verify that a separation of radioactive and non-radioactive calcine components was possible. Bench-scale chlorination experiments were completed subsequently in a variety of reactor configurations including: a fixed-bed reactor (reactive gases flowed around and not through the particle bed), a packed/fluidized-bed reactor, and a packed-bed reactor (reactive gases flowed through the particle bed). Chemical analysis of the reaction products generated during the chlorination experiments verified the predictions made by the equilibrium calculations. An empirical first-order kinetic rate expression was developed for each of the reactor configurations. 20 refs., 16 figs., 21 tabs

Waste generated by the future decommissioning of the Magurele VVR-S Research Reactor

International Nuclear Information System (INIS)

Dragolici, F.; Turcanu, C.N.; Dragolici, A.C.

2001-01-01

Nuclear Research Reactor WWR-S from the National Institute of Research and Development for Physics and Nuclear Engineering 'Horia Hulubei', Bucharest-Magurele, was commissioned in July 1957 and it was shut down in December 1997. At the moment the reactor is in conservation state. During its operation this reactor worked at an average power of 2MW, almost 3216 h/year, producing a total thermal power of 230 x 10 3 MWh. No major modifications or improvements were made during the 40 years of operation to the essential parts of the reactor, respective to the primary cooling system, reactor vessel, active core and electronic devices. So, all components of the measure, control and protection systems are old, generally at the technical level of the 1950s, therefore a reason why in December 1997 the operation was ceased. At present, the reactor can be considered, by IAEA definition in the first stage (reactor shut down, but the vital functions are maintained and monitored). The survey is related to the second stage - restrictive use of the area. To develop a real decommissioning project, it was first necessary to evaluate the volume and the characteristics of the radioactive waste which will be generated. Radioactive waste generated during the decommissioning of Magurele WR-S research reactor may be classified as: Activated wastes (internal structures, horizontal channels and thermal column, biological shield); Contaminated wastes (primary circuit non-activated components, hot cells, some technological rooms as main hall, pumps room, radioactive material transfer areas, ventilation building and stack); Possibly contaminated materials from any area of reactor building and ventilation building. After 40 years of nuclear research activities, all such areas are suspected of contamination. The volume of wastes that will result from WWR-S Research Reactor decommissioning is summarized

D-3He fueled FRC reactor 'ARTEMIS-L'

International Nuclear Information System (INIS)

Momota, Hiromu; Tomita, Yukihiro; Ishida, Akio; Kohzaki, Yasuji; Nakao, Yasuyuki; Nishikawa, Masabumi; Ohi, Shoichi; Ohnishi, Masami.

1992-09-01

A neutron-lean D- 3 He fueled field reversed configuration (FRC) fusion reactor is studied on the bases of former high-efficiency ARTEMIS design. Certain improvements such as effective axial contracting plasma heating and cusp-type direct energy converters as well as an empirical scale of the energy confinement are introduced. The resultant total neutron load onto the first wall of the plasma chamber is as low as 0.1 MW/m 2 , which enable the life of the first wall or the structural materials to be longer than the whole life of the reactor. The attractive characteristics of the neutron-lean reactor follow in the ARTEMIS design: it is socially acceptable in views of radioactivity and fuel resources, and the cost of electricity appears to be cheap compared with that from a light water reactor. Critical physics and engineering issues for performing the ARTEMIS-L reactor are clarified. (author)

Immobilization of Ion Exchange radioactive resins of the TRIGA Mark III Nuclear Reactor; Inmovilizacion de resinas de intercambio ionico radiactivas del reactor nuclear TRIGA Mark III

Energy Technology Data Exchange (ETDEWEB)

Garcia Martinez, H

1999-07-01

In the last decades many countries in the world have taken interest in the use, availability, and final disposal of dangerous wastes in the environment, within these, those dangerous wastes that contain radioactive material. That is why studies have been made on materials used as immobilization agent of radioactive waste that may guarantee its storage for long periods of time under drastic conditions of humidity, temperature change and biodegradation. In mexico, the development of different applications of radioactive material in the industry, medicine and investigation, have generated radioactive waste, sealed and open sources, whose require a special technological development for its management and final disposal. The present work has as a finality to develop the process and define the agglutinating material, bitumen, cement and polyester resin that permits immobilization of resins of Ionic Exchange contaminated by Barium 153, Cesium 137, Europium 152, Cobalt 60 and Manganese 54 generated from the nuclear reactor TRIGA Mark III. Ionic interchange contaminated resin must be immobilized and is analysed under different established tests by the Mexican Official Standard NOM-019-NUCL-1995 {sup L}ow level radioactive wastes package requirements for its near-surface final disposal. Immobilization of ionic interchange contaminated resins must count with the International Standards applicable in this process; in these standards, the following test must be taken in prototype examples: Free-standing water, leachability, compressive strength, biodegradation, radiation stability, thermal stability and burning rate. (Author)

Biological export of radioactive materials from a leaching pond in SE Idaho

International Nuclear Information System (INIS)

Millard, Jere B.

1978-01-01

A radioecological investigation was conducted to quantify biological export of radioactive materials from a test reactor area leaching pond located on the Idaho National Engineering Laboratory site in southeast Idaho. An estimated 42,000 Ci have been discharged to the pond since 1952. Approximately 35 gamma emitting radionuclides are detectable in unfiltered water. Biomass estimates and mean radionuclide concentrations were determined for major pond compartments. A radionuclide inventory of the pond ecosystem was constructed listing totals for radioactivity present in each compartment. Mean concentrations of predominant radionuclides and population census data were used to estimate biologically exported materials. Particular attention was paid to migrant waterfowl, a resident population of barn swallows (Hirundo rustica), and nesting shore birds. Whole body gamma spectra indicated 15 or more detectable fission and activation products associated with swallows and shore birds, and 20 or more for waterfowl. Concentration factors relative to filtered pond water were also calculated. Finally, biologically exported radioactive materials were compared with total amounts present in the pond. (author)

Excess-pressure suppression device in a reactor container

International Nuclear Information System (INIS)

Nishio, Masahide

1985-01-01

Purpose: To reliably decrease the radioactivity of radioactive gases when they are released externally. Constitution: The exit of a gas exhaust pipe for discharging gases in a reactor container, on generation of an excess pressure in the reactor container upon loss of coolant accident, is adapted to be always fluided in the cooling tank. Then, the exhaust gases discharged in the cooling tank is realeased to the atmosphere. In this way, the excess pressure in the reactor container can be prevented previously and the radioactivity of the gases released externally is significantly reduced by the scrubbing effect. (Kamimura, M.)

Guidelines for calculating radiation doses to the public from a release of airborne radioactive material under hypothetical accident conditions in nuclear reactors

International Nuclear Information System (INIS)

1989-09-01

This Standard provides guidelines and a methodology for calculating effective doses and thyroid doses to people (either individually or collectively) in the path of airborne radioactive material released from a nuclear facility following a hypothetical accident. The specific radionuclides considered in the Standard are those associated with substances having the greatest potential for becoming airborne in reactor accidents (eg, tritium (HTO), noble gases and their daughters (Kr-Rb, Xe-Cs), and radioiodines (I)); and certain radioactive particulates (eg, Cs, Ru, Sr, Te) that may become airborne under exceptional circumstances

Role of electromagnetic filter in limitating radioactivity in the primary circuits of light water reactors

International Nuclear Information System (INIS)

Dolle, L.

1978-01-01

High temperature electromagnetic filtration of particulate corrosion products can be carried out with discharges up to 5% of the cooling flow rate. It allows efficient extraction of particulate matter which rate constants required for considerable reduction of activable crud deposition in the core. The paper holds a review of the preventing operation in the primary circuit of a PWR, and reports experimental results of efficiency measurments with an electromagnetic filter set in out-of-pile and in-pile pressurized water loops. The notable efficiencies towards radioactive fine grain and colloidal matter justify more extensive reactor scale application experiments. (author)

Role of electromagnetic filter in limitating radioactivity in the primary circuits of light water reactors

International Nuclear Information System (INIS)

Dolle, L.

1978-01-01

High temperature electromagnetic filtration of particulate corrosion products can be carried out with discharges up to 5% of the cooling flow rate. It allows efficient extraction of particulate matter with rate constants required for considerable reduction of activable crud deposition in the core. The paper holds a review of the preventing operation in the primary circuit of a PWR, and reports experimental results of efficiency measurements with an electromagnetic filter set in out-of-pile and in-pile pressurized water loops. The notable efficiencies towards radioactive fine grain and colloidal matter justify more extensive reactor scale application experiments

Measurement of liquid radioactive materials for monitoring radioactive emissions

International Nuclear Information System (INIS)

1977-10-01

This draft regulation applies to measuring equipment for liquid radioactive materials for the monitoring of the radioactive discharges from stationary nuclear power plants with LWR and HTR reactors. Demands made on the measuring procedure, methods of concentration determination, balancing, indication of limiting values, and inspections are layed down. The draft regulation deals with: 1) Monitoring liquid radioactive discharges: Water and similar systems; radionuclides and their detection limits, radioactively contaminated water (waste water); secondary cooling water; power house cooling water; primary cooling water; flooding water; 2) Layout of the measuring and sampling equipment and demands made on continuous and discontinuous measuring equipment; demands made on discontinuous α and β measuring equipment; 3) Maintenance and repair work; inspections; repair of defects; 4) Demands made on documentation; reports to authorities; 5) Supplement: List of general and reference regulations. (orig./HP) [de

Future view of total energy system and reactor engineering and reactor physics

International Nuclear Information System (INIS)

Ozawa, T.

1974-01-01

This paper outlines the present status of fission reactors and fusion reactors. The conversion ratio of light water reactors is 0.5, and the efficiency is 32% because of relatively low temperature. Both pressurized water reactors and boiling water reactors are technically well developed, their performances are well known, and the fuel cycle is well developed, so that both reactors have monopolized power reactor market. But the reprocessing of spent fuel and the treatment of their hazards are inevitable, and the construction and enlargement of reprocessing facilities are indispensable. In LMFBR's tight sealing is easy because they are non-pressurized, and the efficiency is 41%. But liquid sodium is strongly activated and recirculated, so that chemical obstruction due to the breakage of recirculating pumps, pipings, and heat exchangers may occur, and the hazard of plutonium is large. Regarding controlled thermo-nuclear fusion reactors, because Lawson criterion must be satisfied, two methods of plasma confinement are now experimented. One is the plasma confinement by strong magnetic field of 50 KG to 100 KG, and the other is the confinement by the implosion method with high-power laser beam. The latter has much more uncertainties than the former, but recently both methods have made much progress. (Tai, I)

Removal of radioactive sodium from experimental breeder reactor-II components and conversion to a disposable solid waste: alcohol recovery

International Nuclear Information System (INIS)

Krusl, J.R.; Washburn, R.A.

1985-01-01

Radioactive sodium is removed from Experimental Breeder Reactor-II components by immersing the components in denatured alcohol until the sodium has reacted with the alcohol. The resulting radioactive sodium-alcohol solution must be processed to separate and convert the sodium to a solid waste for disposal. A process was developed and is described that converts radioactive sodium dissolved in alcohol to a dry powdered carbonate waste product and recovers the alcohol for reuse. The sodium-alcohol waste solution, after adjustment for proper sodium and water content, is fed to a wiped-film evaporator operated at 190 0 C and maintained with a CO 2 atmosphere that converts the dissolved sodium to anhydrous Na 2 CO 3 . The end product, about85 to 90 wt% Na 2 CO 3 , is directed into a 208-l (55-gal) drum for disposal. Alcohol distilled during the process is condensed, collected, and dried for immediate reuse. The composition of the alcohol is not altered in the process

A radioactive controversy

International Nuclear Information System (INIS)

Engler, Veronica

2002-01-01

During 2002, the National Congress of Argentina began discussing the 'Agreement between the Republic of Argentina and Australia on cooperation in the peaceful uses of the nuclear energy'. This document has revived the debate regarding development of a national nuclear industry. The debate was spurred by a commercial contract signed in 2000 by INVAP, an Argentinean company who sold a nuclear reactor to the ANSTO, Australian Nuclear and Technology Organization. More than sixty non-governmental organizations are opposed to the ratification of the agreement, because they interpret that the text leaves the door wide open for the transport and deposit of Australian nuclear waste to Argentina, to be processed in national territory. Article 41 of the Argentinean National Constitution, explicitly prohibits the generation of any income from 'radioactive residues'. Those who support the agreement say that it does not promote the deposit of nuclear waste in Argentina, and argue that environmentalists are hampering efforts of this advanced technological industry to flourish in Argentina. The point of conflict in the agreement lies in article 12, which states that Argentina will continue the process of reactor-driven irradiated fuel outside Argentina. Once the treatment is completed, the fuel conditioned and the resulting waste must return to the country of origin for their storage. The possibility of spent fuel being sent to Argentina lies in the hypothetical case that the French company Cogema, which currently holds treatment responsibility, stops treatment sometime within the next fifteen years, when the fuel must be treated. The non-ratification of the agreement on Argentina part will not imply any sort of impediment in the realization of the reactor, it will only put on hold the possibility that the Australians spent fuels will complete treatment in Argentina. The constitutionality of the agreement lies in the question of waste, but this too is not a simple question. The

Low activation material design methodology for reduction of radio-active wastes of nuclear power plant

International Nuclear Information System (INIS)

Hasegawa, A.; Satou, M.; Nogami, S.; Kakinuma, N.; Kinno, M.; Hayashi, K.

2007-01-01

Most of the concrete shielding walls and pipes around a reactor pressure vessel of a light water reactor become low level radioactive waste at decommission phase because they contain radioactive nuclides by thermal-neutron irradiation during its operation. The radioactivity of some low level radioactive wastes is close to the clearance level. It is very desirable in terms of life cycle cost reduction that the radioactivity of those low level radioactive wastes is decreased below clearance level. In case of light water reactors, however, methodology of low activation design of a nuclear plant has not been established yet because the reactor is a large-scale facility and has various structural materials. The Objectives of this work are to develop low activation material design methodology and material fabrication for reduction of radio-active wastes of nuclear power plant such as reinforced concrete. To realize fabrication of reduced radioactive concrete, it is necessary to develop (1) the database of the chemical composition of raw materials to select low activation materials, (2) the tool for calculation of the neutron flux and the spectrum distribution of nuclear plants to evaluate radioactivity of reactor components, (3) optimization of material process conditions to produce the low activation cement and the low activation steels. Results of the data base development, calculation tools and trial production of low activation cements will be presented. (authors)

Method for operating nuclear reactor

International Nuclear Information System (INIS)

Utamura, Motoaki; Urata, Megumu; Uchida, Shunsuke

1978-01-01

Purpose: In order to judge the fuel failures, if any, without opening a reactor container for BWR type reactors, a method has been described for measuring the difference between the temperature dependent iodine spike value and the pressure dependent iodine spike value in the pressure vessel. Method: After the scram of a nuclear reactor, steam generated by decay heat is condensed in a remaining heat exchanger and cooling water is returned through a recycling pipe line to a reactor core. At the same time, a control rod drive system pump is operated, the reactor core is filled with the cooling water. Then, the coolant is taken from the recycling pipe line to cool the reactor core. After applying the temperature fluctuation, the cooling water is sampled at a predetermined time interval at a sampling point to determine the changes with time in the radioactive concentration of iodine. When the radioactivity of iodine in the cooling water is lowered sufficiently by a reactor purifying system, the nuclear reactor vessel is depressurized. After applying pressure fluctuation, iodine spike value is determined. (Kawakami, Y.)

A totally automatic density meter for radioactive solutions

International Nuclear Information System (INIS)

Hochel, R.C.

1987-02-01

A totally automatic density meter for measuring the density of radioactive liquid (plutonium nitrate) samples was developed and built for use at the Savannah River Plant. The measurement cell (vibrating U-tube) and other wetted parts are glovebox-contained and are remoted from the electronics and control instrumentation. The only operator actions required are insertion of a sample vial into the system, starting the analysis, and removing the vial about 90 seconds later. The sample measurement takes about 3 to 4 minutes and uses 10 mL of sample; another 5 to 6 minutes is required for a water/air measurement-control check, which leaves the system ready for the next sample. No water bath is needed because a computer algorithm is applied to the measurement to correct it to a standard reference temperature. The system is normally operated under computer control, but a programmable logic controller is available for backup. The system may also be operated manually by means of a switchpanel. 5 refs., 3 figs

Overview of fusion reactor safety

International Nuclear Information System (INIS)

Cohen, S.; Crocker, J.G.

1981-01-01

Use of deuterium-tritium burning fusion reactors requires examination of several major safety and environmental issues: (1) tritium inventory control, (2) neutron activation of structural materials, fluid streams and reactor hall environment, (3) release of radioactivity from energy sources including lithium spill reactions, superconducting magnet stored energy release, and plasma disruptions, (4) high magnetic and electromagnetic fields associated with fusion reactor superconducting magnets and radio frequency heating devices, and (5) handling and disposal of radioactive waste. Early recognition of potential safety problems with fusion reactors provides the opportunity for improvement in design and materials to eliminate or greatly reduce these problems. With an early start in this endeavor, fusion should be among the lower risk technologies for generation of commercial electrical power

Study of the accumulation and distribution of the radioactivity in the cooling circuit of the BOR-60 reactor

International Nuclear Information System (INIS)

Kizin, V.D.; Konyashov, V.V.; Lisitsyn, E.S.; Polyakov, V.I.; Chechetkin, Yu.V.

1976-04-01

The results of measurements of the radioactivity of the coolant and the deposits in the primary circuit of the BOR-60 reactor during its five years of operation are discussed. The values calculated for the exposure dose rate from the piping system and the contribution of the γ-radiation from the corrosion and fission product nuclides are given. The efficiency of coolant draining from the pipes in reducing the dose rate is estimated. (orig.) [de

Decommissioning activities for Salaspils research reactor - 59055

International Nuclear Information System (INIS)

Abramenkovs, A.; Malnacs, J.

2012-01-01

In May 1995, the Latvian government decided to shut down the Salaspils Research Reactor (SRR). The reactor is out of operation since July 1998. A conceptual study for the decommissioning of SRR has been carried out by Noell-KRC-Energie- und Umwelttechnik GmbH at 1998-1999. The Latvian government decided to start the direct dismantling to 'green field' in October 26, 1999. The upgrade of decommissioning and dismantling plan was performed in 2003-2004 years, which change the main goal of decommissioning to the 'brown field'. The paper deals with the SRR decommissioning experience during 1999-2010. The main decommissioning stages are discussed including spent fuel and radioactive wastes management. The legal aspects and procedures for decommissioning of SRR are described in the paper. It was found, that the involvement of stakeholders at the early stages significantly promotes the decommissioning of nuclear facility. Radioactive waste management's main efforts were devoted to collecting and conditioning of 'historical' radioactive wastes from different storages outside and inside of reactor hall. All radioactive materials (more than 96 tons) were conditioned in concrete containers for disposal in the radioactive wastes repository 'Radons' at Baldone site. The dismantling of contaminated and activated components of SRR systems is discussed in paper. The cementation of dismantled radioactive wastes in concrete containers is discussed. Infrastructure of SRR, including personal protective and radiation measurement equipment, for decommissioning purposes was upgraded significantly. Additional attention was devoted to the free release measurement's technique. The certified laboratory was installed for supporting of all decommissioning activities. All non-radioactive equipments and materials outside of reactor buildings were released for clearance and dismantled for reusing or conventional disposing. Weakly contaminated materials from reactor hall were collected

Treatment of organic radioactive waste in decommissioning project

International Nuclear Information System (INIS)

Dimovic, S.; Plecas, I.

2003-01-01

This paper describes methods of treatment of organic radioactive waste in the aspect of its integral part of radioactive waste which will arise during decommissioning process of nuclear power reactor RA (author)

Reactor safety study. An assessment of accident risks in U. S. commercial nuclear power plants. Appendix VI. Calculation of reactor accident consequences. [PWR and BWR

Energy Technology Data Exchange (ETDEWEB)

1975-10-01

Information is presented concerning the radioactive releases from the containment following accidents; radioactive inventory of the reactor core; atmospheric dispersion; reactor sites and meteorological data; radioactive decay and deposition from plumes; finite distance of plume travel; dosimetric models; health effects; demographic data; mitigation of radiation exposure; economic model; and calculated results with consequence model.

Tasks related to increase of RA reactor exploitation and experimental potential, 01. Designing the protection chamber in the RA reactor hall for handling the radioactive experimental equipment (I-II) Part II, Vol. II

International Nuclear Information System (INIS)

Pavicevic, M.

1963-07-01

This second volume of the project for construction of the protection chamber in the RA reactor hall for handling the radioactive devices includes the technical description of the chamber, calculation of the shielding wall thickness, bottom lead plate, horizontal stability of the chamber, cost estimation, and the engineering drawings

Device for monitoring radioactivity of cooling water in a nuclear reactor

International Nuclear Information System (INIS)

Osawa, Yasuo.

1975-01-01

Object: To provide means for monitoring the peak channel of γ-ray spectrum in cooling water and the time-wise attenuation value of the counts of the peak channels and capable of early detecting abnormal phenomenon with a constant reference. Structure: It is provided with a γ-ray detector, a multi-channel γ-ray spectrometer, peak determining means for determining the peak position of the spectrum from the count value of each channel of the γ-ray spectrum, a peak channel memory for memorizing the channel number of the peak channels, attenuation measurement means for measuring the attenuation value by repeatedly measuring the count value of the peak channel, an attenuation memory for memorizing the attenuation value and a variation detector for detecting the variation in radioactivity of the reactor cooling water from the count value of the peak channel and peak channel attenuation value. When a difference is detected by the variation detector, the measurement value is provided as defective value. (Kamimura, M.)

Impact of partitioning and transmutation in radioactive waste management

International Nuclear Information System (INIS)

Magill, J.

2006-01-01

Nuclear energy provides a significant contribution to the overall energy supply in Europe. With 148 reactors in 13 of the 25 Member States producing a total power of 125 G We, the resulting energy generation of 850 TWh per year provides 35% of the total electrical energy requirements in the European Union. Worldwide, 441 commercial reactors operate in 31 countries and provide 17% of the electrical requirements. Currently 32 nuclear reactors are being built worldwide mostly in India, China and in neighbouring countries. The used fuel discharged from nuclear power plants constitutes the main contribution to nuclear waste in countries which do not undertake reprocessing. As such, its disposal requires isolation from the biosphere in stable deep geological formations for long periods of time (some hundred thousand years) until its radioactivity decreases through the process of radioactive decay. Ways for significantly reducing the volumes and radio toxicities of the waste and to shorten the very long times for which the waste must be stored safely are being investigated. This is the motivation behind the partitioning and transmutation (P and T) activities worldwide. Most of the hazard from the spent fuel stems from only a few chemical elements, namely plutonium, neptunium, americium, curium, and some long-lived fission products such as iodine, caesium and technetium. At present approximately 2500 t of spent fuel are produced annually in the EU, containing about 25 t of plutonium, and 3.5 t of the minor actinides neptunium, americium and curium, and about 3 t of long-lived fission products. These radioactive by-products, although present in relatively low concentrations in the used fuel, are a hazard to life forms when released into the environment. This paper addresses the potential impact of P and T on the long-term disposal of nuclear waste. In particular, it evaluates how realistic P and T scenarios can lead to a reduction in the time required for the waste to be

TOKMINA, Toroidal Magnetic Field Minimization for Tokamak Fusion Reactor. TOKMINA-2, Total Power for Tokamak Fusion Reactor

International Nuclear Information System (INIS)

Hatch, A.J.

1975-01-01

1 - Description of problem or function: TOKMINA finds the minimum magnetic field, Bm, required at the toroidal coil of a Tokamak type fusion reactor when the input is beta(ratio of plasma pressure to magnetic pressure), q(Kruskal-Shafranov plasma stability factor), and y(ratio of plasma radius to vacuum wall radius: rp/rw) and arrays of PT (total thermal power from both d-t and tritium breeding reactions), Pw (wall loading or power flux) and TB (thickness of blanket), following the method of Golovin, et al. TOKMINA2 finds the total power, PT, of such a fusion reactor, given a specified magnetic field, Bm, at the toroidal coil. 2 - Method of solution: TOKMINA: the aspect ratio(a) is minimized, giving a minimum value for Bm. TOKMINA2: a search is made for PT; the value of PT which minimizes Bm to the required value within 50 Gauss is chosen. 3 - Restrictions on the complexity of the problem: Input arrays presently are dimensioned at 20. This restriction can be overcome by changing a dimension card

Osiris reactor descriptive report

International Nuclear Information System (INIS)

1976-03-01

OSIRIS is a swimming pool reactor of 70 MW thermal power. Its main purpose is the irradiation of reactor materials in high neutron flux. A description is given of the air conditioning, ventilation, and radioactive gas removal system. (R.L.)

State of radioactive waste management is power reactor facilities and state of radiation exposure of workers who engaged in radiation works in fiscal 1993

International Nuclear Information System (INIS)

1994-01-01

This report is the summary of the reports on radiation control and others submitted by those who installed practical power reactor facilities based on the relevant law in fiscal 1993. The amounts of release of radioactive gaseous and liquid wastes were sufficiently smaller than the target value of the yearly release control for attaining the target value of dose that the public around the facilities receive. As to the state of control of radioactive solid waste, the amount of drum generation tended to decrease year by year, and the cumulative amount to be preserved tended to level off. The dose equivalent that the individuals who engaged in radiation works received was smaller than the limit value in all nuclear power stations. The total dose equivalent for those workers in fiscal 1993 was 86.65 man Sv. Hereafter, the automation and remote operation of works, the water quality control for reducing crud and so on will be promoted to reduce radiation exposure. The reference data on the state of control of gaseous, liquid and solid wastes, and the state of control of radiation exposure of workers are attached. (K.I.)

Radioactive iodine releases from nuclear power plant, (2)

International Nuclear Information System (INIS)

Naritomi, Mitsuo

1974-01-01

Internal radiation dose through the respiratory intake of fission products is predominantly due to radioactive iodine not only at the time of reactor accidents but also in normal operation of nuclear facilities. Technological studies in this field have thus been quite active to this day. With the rapid advance of nuclear power generation in recent years, the efforts to reduce environmental release of radioactive iodine and to enhance environmental safety are all the more emphasized. Experiences in the Japan Atomic Energy Research Institute during past about six years are described concerning the radioactive iodine release to the atmosphere in 131 I production and the measures taken to reduce the release. Then, problems are expounded regarding the radioactive iodine release at the time of reactor accidents and in spent fuel reprocessing. (Mori, K.)

Tasks related to increase of RA reactor exploitation and experimental potential, 04. Device for transport of radioactive reactor channels and semi channels of the RA reactor, design project (I-III) Part II, Vol. II; Radovi na povecanju eksploatacionih i eksperimentalnih mogucnosti reaktora RA, 04. Uredjaj za transport aktivnih tehnoloskih kanala I semikanala reaktora RA - izrada projekta (I-III), II Deo, Album II

Energy Technology Data Exchange (ETDEWEB)

Pavicevic, M [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Serbia and Montenegro)

1963-07-15

This second volume includes calculations of the main components of the transporter, description of the mechanical part of the transporter and the engineering drawing of the device for transport of radioactive reactor channels and semi channels of the RA reactor.

Backflushable filter experience at the N Reactor

International Nuclear Information System (INIS)

Ball, B.; Best, W.T.; Keith, R.C.

1987-01-01

The N Reactor is an 4000 MWt, light-water cooled, graphite-moderated reactor located on the Hanford Site in Washington State. A radwaste pilot plant to process plant effluent was constructed in order to maximize future efficiency when a full size radioactive processing facility is built. The pilot plant's purpose is to vary operational parameters such as filtration and ion exchange on a smaller scale to gather as much data as possible. The input to the pilot plant is radioactive drain lines from the N Reactor. The effluent passes through a backflushable filter and a series of ion exchange columns all scaled down from the future proposed facility. A backflushable filter was selected for this application because of the specific characteristics of the plant effluent and the potential reduced operating costs. The filter performance has been excellent in terms of filtration of the effluent. Typical total suspended solids in the plant effluent range from 1 to 6.1 ppm; the filter reduces this value to less than 0.1 ppm. In addition to outstanding filtration efficiency, the use of a precoat material on the filter has resulted in impressive decontamination factors. The filter has been successful in removing up to 50% of the influent activity. An improved performance of several nuclides over other filtration systems has also been achieved. By varying the composition and amount of precoat material on the filter, substantial reductions in waste volumes (and associated operating and disposal costs) have been demonstrated while maintaining a high degree of removal of both activity and total suspended solids

Radionuclide trap for liquid metal cooled reactors

International Nuclear Information System (INIS)

McGuire, J.C.; Brehm, W.F.

1978-10-01

At liquid metal cooled reactor operating temperatures, radioactive corrosion product transport and deposition in the primary system will be sufficiently high to limit access time for maintenance of system components. A radionuclide trap has been developed to aid in controlling radioactivity transport. This is a device which is located above the reactor core and which acts as a getter, physically immobilizing radioactive corrosion products, particularly 54 Mn. Nickel is the getter material used. It is most effective at temperatures above 450 0 C and effectiveness increases with increasing temperature. Prototype traps have been tested in sodium loops for 40,000 hours at reactor primary temperatures and sodium velocities. Several possible in-reactor trap sites were considered but a location within the top of each driver assembly was chosen as the most convenient and effective. In this position the trap is changed each time fuel is changed

An interim report of the Subcommittee on Radioactive Waste Countermeasures: measures for radioactive waste treatment and disposal

International Nuclear Information System (INIS)

1984-01-01

The Subcommittee on Radioactive Waste Countermeasures has studied on the measures for land disposal of low-level radioactive wastes and ultra-low-level radioactive wastes and the measures for treatment and disposal of high-level radioactive wastes and transuranium wastes. The results of studies so far are presented as an interim report. In disposal of low-level radioactive wastes, the land disposal is being required increasingly. The measures according to the levels of radioactivity are necessary. For the ultra-low-level radioactive wastes, their occurrence in large quantities is expected along with reactor decommissioning. In disposal of the high-level radioactive wastes, the present status is a transition toward the practical stages. Transuranium wastes should increase in their arising in the future. (Mori, K.)

Planning the Decommissioning of Research Reactors

Energy Technology Data Exchange (ETDEWEB)

Podlaha, J., E-mail: pod@ujv.cz [Nuclear Research Institute Rez, 25068 Rez (Czech Republic)

2013-08-15

In the Czech Republic, three research nuclear reactors are in operation. According to the valid legislation, preliminary decommissioning plans have been prepared for all research reactors in the Czech Republic. The decommissioning plans shall be updated at least every 5 years. Decommissioning funds have been established and financial resources are regularly deposited. Current situation in planning of decommissioning of research reactors in the Czech Republic, especially planning of decommissioning of the LVR-15 research reactor is described in this paper. There appeared new circumstances having wide impact on the decommissioning planning of the LVR-15 research reactor: (1) Shipment of spent fuel to the Russian Federation for reprocessing and (2) preparation of processing of radioactive waste from reconstruction of the VVR-S research reactor (now LVR-15 research reactor). The experience from spent fuel shipment to the Russian Federation and from the process of radiological characterization and processing of radioactive waste from reconstruction of the VVR-S research reactor (now the LVR-15 research reactor) and the impact on the decommissioning planning is described in this paper. (author)

Volume reduction and solidification of liquid and solid low-level radioactive waste

International Nuclear Information System (INIS)

May, J.R.

1979-01-01

This paper presents a brief background of the development of a method of radioactive waste volume reduction using a unique fluidized bed calciner/incinerator. The volume reduction system is capable of processing a variety of liquid chemical wastes, spent ion exchange resin beads, filter treatment sludges, contaminated lubricating oils, and miscellaneous combustible solids such as paper, rags, protective clothing, wood, etc. All of these wastes are processed in one chemical reaction vessel. Detailed process data is presented that shows the system is capable of reducing the total volume of disposable radioactive waste generated by light water reactors by a factor of 10. Equally important to reducing the volume of power reactor radwaste is the final form of the stored or disposable radwaste. This paper also presents process data related to a new radwaste solidification system, presently being developed, that is particularly suited for immobilizing the granular solids and ashes resulting from volume reduction by calcination and/or incineration

Method of treatment in a system passing radioactive material

Energy Technology Data Exchange (ETDEWEB)

Kamiya, K; Kinoshita, M; Asakura, Y

1976-05-14

A method to ensure the safety of the reactor and reduce radiation exposure dose by preventing oxygen hydrogen reaction of the reactor off-gas and accumulation of the radioactive material is described. Substances which are accumulated in an off-gas duct and are likely to capture radioactive material (for instance Pd catalyst falling from a recombiner) is changed into a stable material (for instance, PdI/sub 2/) which is hot likely to capture radioactive material through reaction with a stabilizer (for instance, I/sub 2/, Cl/sub 2/, HCl, etc.). This stabilized material is washed off the atomic power plant system.

REACTOR FUEL ELEMENTS TESTING CONTAINER

Science.gov (United States)

Whitham, G.K.; Smith, R.R.

1963-01-15

This patent shows a method for detecting leaks in jacketed fuel elements. The element is placed in a sealed tank within a nuclear reactor, and, while the reactor operates, the element is sparged with gas. The gas is then led outside the reactor and monitored for radioactive Xe or Kr. (AEC)

BN-350 decommissioning problems of radioactive waste management

International Nuclear Information System (INIS)

Galkin, A.; Tkachenko, V.

2002-01-01

Pursuant of modern concept on radioactive waste management applied in IAEA Member States all radioactive wastes produced during the BN-350 operation and decommissioning are subject to processing in order to be transformed to a form suitable for long-term storage and final disposal. The first two priority objectives for BN-350 reactor are as follows: cesium cleaning from sodium followed by sodium drain, and processing; processing of liquid and solid radioactive waste accumulated during BN-350 operation. Cesium cleaning from sodium and sodium processing to NaOH will be implemented under USA engineering and financial support. However the outputted product might be only subject to temporary storage under special conditions. Currently the problem is being solved on selection of technology for sodium hydroxide conversion to final product incorporated into cement-like matrix ready for disposal pursuant to existing regulatory requirements. Industrial installation is being designed for liquid radioactive waste processing followed by incorporation to cement matrix subject to further disposal. The next general objective is management of radioactive waste expected from BN-350 decommissioning procedure. Complex of engineering-radiation investigation that is being conducted at BN-350 site will provide estimation of solid and liquid radioactive waste that will be produced during the course of the BN-350 decommission. Radioactive wastes that will be produced may be shared for primary (metal structures of both reactor and reactor plant main and auxiliary systems equipment as well as construction wastes of dismantled biological protection, buildings and structures) and secondary (deactivation solutions, tools, materials, cloth, special accessory, etc.). Processing of produced radioactive wastes (including high activity waste) requires the use of special industrial facilities and construction of special buildings and structures for arrangement of facilities mentioned as well as for

General radioactive contamination of the biosphere in the Netherlands

International Nuclear Information System (INIS)

1980-01-01

The Coordinating Committee for the Monitoring of Radioactive and Xenobiotic Substances (C.C.R.X.) reports the results of the radioactivity measurements in 1979. These are divided into measurements for the National Measuring Programme and Additional Measurements. The former include the analyses considered essential for an efficacious control of the radioactivity of the biosphere and are performed in air, soil, surface water, milk and in deposition on the surface of the earth. Samples of milk and grass from the surroundings of nuclear reactors have also been analysed. Additional measurements comprises orientating research for specific radionuclides which may be present in some samples, and other investigations which may procure useful information. Results of determinations of radionuclides in some fishery-products from the Dutch waters are given in view of the potential which some marine organisms have to concentrate fission products and especially activated corrosion products from nuclear installations. After a discussion of the results for the National Measuring Programme, a calculation is given of the total artificial radioactivity in the average Dutch diet in 1979 and of the total mean annual radiation dose the Dutch population received as a result of the presence of artificial radionuclides. Different methods studied to calculate the bone dose due to Sr-90 in the diet are outlined as an appendix. (Auth.)

Protection of environmental contamination by radioactive materials and remediation of environment

International Nuclear Information System (INIS)

2003-05-01

This report consisted of the environmental contamination of radioactive and non-radioactive materials. 38 important accident examples of environmental contamination of radioactive materials in the world from 1944 to 2001 are stated. Heavily polluted areas by accidents are explained, for example, Chernobyl, atomic reactor accidents, development of nuclear weapon in USA and USSR, radioactive waste in the sea. The environmental contamination ability caused by using radioactive materials, medical use, operating reactor, disposal, transferring, crashing of airplane and artificial satellite, release are reported. It contains measurements and monitor technologies, remediation technologies of environmental contamination and separation and transmutation of radioactive materials. On the environmental contamination by non-radioactive materials, transformation of the soil contamination in Japan and its control technologies are explained. Protection and countermeasure of environmental contamination of radioactive and non-radioactive materials in Japan and the international organs are presented. There are summary and proposal in the seventh chapter. (S.Y.)

Cleanup of radioactivity contamination in environment

International Nuclear Information System (INIS)

Kosako, Toshiso

1994-01-01

Environmental radioactivity cleanup is needed under a large scale accident in a reactor or in an RI irradiation facility which associates big disperse of radioactivities. Here, the fundamental concept including a radiation protection target, a period classification, planning, an information data base, etc. Then, the methods and measuring instruments on radioactivity contamination and the cleanup procedure are explained. Finally, the real site examples of accidental cleanup are presented for a future discussion. (author)

The timing of reactor dismantling

International Nuclear Information System (INIS)

Roberts, P.

2000-01-01

Work has been progressing across the world for the decommissioning of nuclear reactors. The initial work focused on the early, complete dismantling but this was associated with small size reactors and was done for experimental or demonstration purposes. The situation now is that an increasing number of full size power reactors are being shutdown and decision are being made as to the decommissioning strategy to be applied, e.g. with respect to the appropriate timing of reactor dismantling. There are two basic approaches to the timing of reactor dismantling, which are to either proceed with dismantling on an early time scale or to delay it for a period of years. There are a number of examples worldwide of both approaches being taken but one common feature of the approach taken by most countries is that decisions are made on a case by case basis, taking account of relevant factors, and as a result the strategy can vary from reactor to reactor and from country to country. Decisions on timing take account of the following main factors: safety, radioactive decay, financial factors, radioactive waste, reactor type, technology, repository availability, site re-use, regulatory standards, plant knowledge/records, other issues

Astrid (fast breeder nuclear reactor)

International Nuclear Information System (INIS)

2014-01-01

This document presents ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration), a French project of sodium-cooled fast breeder reactor, fourth generation reactor which should be fuelled by uranium 238 rather than uranium 235, and should therefore need less extracted natural uranium to produce electricity. The operation principle of fast breeder reactors is described. They notably directly consume plutonium, allow an easier radioactive waste management as they transform long life radioactive elements into shorter life elements by transmutation. The regeneration process is briefly described, and the various operation modes are evoked (iso-generator, sub-generator, and breeder). Some peculiarities of sodium-cooled reactors are outlined. The Astrid operation principle is described, its main design innovations outlined. Various challenges are discussed regarding safety of supply and waste processing, and the safety of future reactors. Major actors are indicated: CEA, Areva, EDF, SEIV Alcen, Toshiba, Rolls Royce, and Comex. Some key data are indicated: expected lifetime, expected availability rate, cost. The projected site is Marcoule and fast breeder reactors operated or under construction in the world are indicated. The document also proposes an overview of the background and evolution of reactors of 4. generation

Analysis of the total system life cycle cost for the Civilian Radioactive Waste Management Program. Volume 1. The analysis and its results

International Nuclear Information System (INIS)

1986-04-01

The total-system life-cycle cost (TSLCC) analysis for the Department of Energy's (DOE) Civilian Radioactive Waste Management Program is an ongoing activity that helps determine whether the revenue-producing mechanism established by the Nuclear Waste Policy Act of 1982 is sufficient to cover the cost of the program. This report provides cost estimates for the fourth evaluation of the adequacy of the fee. The total-system cost for the reference authorized-system program is estimated to be 24 to 32 billion (1985) dollars. The total-system cost for the reference improved-performance system is estimated to be 26 to 34 billion dollars. A number of sensitivity cases were analyzed. For the authorized system, the costs for the sensitivity cases studied range from 21 to 39 billion dollars. For the improved-performance system, which includes a facility for monitored retrievable storage, the total-system cost in the sensitivity cases is estimated to be as high as 41 billion dollars. The factors that affect costs more than any other single factor for both the authorized and the improved-performance systems are delays in repository startup. A preliminary analysis of the impact of extending the burnup of nuclear fuel in the reactor was also performed; its results indicate that the impact is insignificant: the total-system cost is essentially unchanged from the comparable constant-burnup cases. The current estimate of the the total-system cost for the reference authorized system is zero to 3 billion dollars (9%) higher than the estimate for the reference system in the January 1985 TSLCC analysis

Centennial of the discovery of radioactivity - 1896-1898/1996-1998

International Nuclear Information System (INIS)

Bimbot, R.; Casse, M.

2009-01-01

This document summarizes the impacts that the discovery of radioactivity in 1896 has had on the scientific world: 1 - historical aspects (biographies of Henri Becquerel, Pierre Curie and Marie Curie-Sklodowska; context; history of radioactivity discovery; examples of radioactive half-lives); 2 - development of matter sciences (radiochemistry; nuclear and particle physics; nuclear and particle astrophysics); 3 - dating and energy applications: isotope dating; power generation (fission, fusion, nuclear reactor components, reactor types, radioactive wastes); 4 - biological, medical and agronomic applications (biological researches, medical diagnosis, clinical exploration and therapies, man's exposure to ionizing radiations, natural and artificial radioactivity, sources, doses and radiation effects, radioactivity in the Saclay area, radioactivity changes with places, research tool in plants biology and agronomic. Reprints of original communications presented by H. Becquerel and P. and M. Curie at the sessions of the French Academy of Sciences between 1896 and 1906, as well as the talks given at the Academy for the funerals of H. Becquerel, are attached to the document. (J.S.)

Overview moderator material for nuclear reactor components

International Nuclear Information System (INIS)

Mairing Manutu Pongtuluran; Hendra Prihatnadi

2009-01-01

In order for a reactor design is considered acceptable absolute technical requirement is fulfilled because the most important part of a reactor design. Safety considerations emphasis on the handling of radioactive substances emitted during the operation of a reactor and radioactive waste handling. Moderator material is a layer that interacts directly with neutrons split the nuclear fuel that will lead to changes in physical properties, nuclear properties, mechanical properties and chemical properties. Reviews moderator of this time is of the types of moderator is often used to meet the requirements as nuclear material. (author)

Radioactive wastes eliminating device

International Nuclear Information System (INIS)

Mitsutsuka, Norimasa.

1979-01-01

Purpose: To eliminate impurities and radioactive wastes by passing liquid sodium in a cold trap and an adsorption device. Constitution: Heated sodium is partially extracted from the core of a nuclear reactor by way of a pump, flown into and cooled in heat exchangers and then introduced into a cold trap for removal of impurities. The liquid sodium eliminated with impurities is introduced into an adsorption separator and purified by the elimination of radioactive wastes. The purified sodium is returned to the nuclear reactor. A heater is provided between the cold trap and the adsorption separator, so that the temperature of the liquid sodium introduced into the adsorption separator is not lower than the minimum temperature in the cold trap to thereby prevent deposition of impurities in the adsorption separator. (Kawakami, Y.)

Understanding radioactive waste

International Nuclear Information System (INIS)

Murray, R.L.

1981-12-01

This document contains information on all aspects of radioactive wastes. Facts are presented about radioactive wastes simply, clearly and in an unbiased manner which makes the information readily accessible to the interested public. The contents are as follows: questions and concerns about wastes; atoms and chemistry; radioactivity; kinds of radiation; biological effects of radiation; radiation standards and protection; fission and fission products; the Manhattan Project; defense and development; uses of isotopes and radiation; classification of wastes; spent fuels from nuclear reactors; storage of spent fuel; reprocessing, recycling, and resources; uranium mill tailings; low-level wastes; transportation; methods of handling high-level nuclear wastes; project salt vault; multiple barrier approach; research on waste isolation; legal requiremnts; the national waste management program; societal aspects of radioactive wastes; perspectives; glossary; appendix A (scientific American articles); appendix B (reference material on wastes)

Understanding radioactive waste

Energy Technology Data Exchange (ETDEWEB)

Murray, R.L.

1981-12-01

This document contains information on all aspects of radioactive wastes. Facts are presented about radioactive wastes simply, clearly and in an unbiased manner which makes the information readily accessible to the interested public. The contents are as follows: questions and concerns about wastes; atoms and chemistry; radioactivity; kinds of radiation; biological effects of radiation; radiation standards and protection; fission and fission products; the Manhattan Project; defense and development; uses of isotopes and radiation; classification of wastes; spent fuels from nuclear reactors; storage of spent fuel; reprocessing, recycling, and resources; uranium mill tailings; low-level wastes; transportation; methods of handling high-level nuclear wastes; project salt vault; multiple barrier approach; research on waste isolation; legal requiremnts; the national waste management program; societal aspects of radioactive wastes; perspectives; glossary; appendix A (scientific American articles); appendix B (reference material on wastes). (ATT)

Volume reduction of radioactive concrete waste generated from KRR-2 and UCP

International Nuclear Information System (INIS)

Min, B. Y.; Choi, W. K.; Park, J. W.; Lee, K. W.

2009-01-01

As a part of a technical development for the volume reduction and stabilization of contaminated concrete wastes generated by dismantling a research reactor and uranium conversion plant, we have developed the volume reduction technology and immobilization of fine powder applicable to an activated heavy weight concrete generated by dismantling KRR-2 and a uranium contaminated light weight concrete produced from a UCP decommissioning. During a decommissioning of nuclear plants and facilities, large quantities of contaminated concrete wastes are generated. The decommissioning of the retired TRIGA MARK II and III research reactors and a uranium conversion plant has been under way. In Korea, two decommissioning projects such as the decommissioning of the retired research reactors (KRR-1 and 2) and a uranium conversion plant (UCP) at the Korea Atomic Energy Research Institute (KAERI) has been carried out. By dismantling KRR-2, more than 260 tons of radioactive concrete wastes are generated among the total 2,000 tons of concrete wastes and more than 60 tons of concrete wastes contaminated with uranium compounds are generated in UCP decommissioning up to now. The volume reduction and recycling of the wastes is essential to reduce the waste management cost with expecting that an approximate disposal cost for low level radioactive waste will be more than 5,000 US dollars per 200 liter waste drum in Korea. It is well known that most of the radioactivity exist in cement mortar and paste composed of concrete. In this context, the volume reduction of concrete waste is based on the separation of radioactive concrete into a clean recyclable aggregates and a radioactive fine cement powder, which can be readily performed by heating to weaken the adherence force between the cement matrix and the aggregates followed by mechanical crushing and milling processes. In this study, we have investigated the characteristics of separation of aggregates and the distribution of radioactivity into

Reactor, radioactive isotopes and nuclear energy: their avatars in Venezuela

Energy Technology Data Exchange (ETDEWEB)

Roche, M

1981-03-01

The decision to bring a fair sized (3MW) research reactor to Venezuela, made in 1954 by a single, ambitious and prestige seeking individual working with a dictatorial government, is a clear case of cargo cult, an implicit desire to import industralized countries' science and technology by purchasing key in hand their expensive machine. The reactor has never ceased to experience difficulties since then, not so much of a physical or mechanical, but rather of a human nature and due to the almost grotesque distance between the machine's potentialities and the quantity and quality of personnel available. Demand and motivation have been scarce, because fossil and hydro energy have been so far plentiful. Military motivation was in theory absent. Perspectives have apparently improved, not that a scientific community has been trained and an infrastructure exists. Radioactive isotopes have been widely used in Venezuela, beginning in 1953, for medical practice and biological research. At present about 2.5 million bolivars worth of radioisotopes are imported annually, mostly from the US and to a lesser extent, from UK. Steps are being taken to train nuclear engineers, since most studies thus far indicate the last few years of the century as the time when nuclear energy will begin to enter the picture, and since a period of at least ten years is needed between the decision to build an atomic power plant and the time it goes into operation. Choice of technique has not been made, but an active, although still small, uranium prospecting program has been initiated. It seems as if, by the end of the century, either nuclear energy will have to supplement other sources, or standard of living of Venezuelans - at least that relative minority who can afford to live well - will drop. 2 figures, 2 tables.

Decontamination and decommissioning of the SPERT-I Reactor Building at the Idaho National Engineering Laboratory. Final report

International Nuclear Information System (INIS)

Dolenc, M.R.

1986-02-01

This final report documents the decontamination and decommissioning of the SPERT-I Reactor Building. This 20- by 40-ft galvanized steel building was dismantled; and the resultant contaminated sludge, liquid, and carbon steel were disposed of at the Radioactive Waste Management Complex of the Idaho National Engineering Laboratory. This report presents the results of the characterization, decision analysis, planning, and decommissioning of the facility. The total cost of these activities was $139,500. Of this total, $103,500 was required for decommissioning operations. (This latter figure represents a 20% savings over the estimated costs generated during the planning effort.) The objectives of decommissioning this facility were to stabilize the seepage pit area and remove the reactor building. The D and D work was divided into two parts; the seepage pit was decommissioned in 1984, and the reactor building in 1985. The entire area was backfilled with radiologically clean soil, graded, and seeded. Two markers were installed to identify the locations of the pit and reactor building. The only isotopes found in either decommissioning operation were cesium-137 and uranium-235 in very low concentrations. Decommissioning operations of the reactor building were carried out during August 1985. The project generate 297 ft 3 of radioactive waste. No personnel radiation exposure above background was received by D and D workers

Handbook of radioactivity measurements procedures. Second edition

International Nuclear Information System (INIS)

Anon.

1985-01-01

This report is concerned with the measurement of radioactivity in general, but specifically it deals with radioactive materials that have become available in the last three decades, from nuclear reactors and particle accelerators, for applications in medicine, scientific research, and industry. It is also concerned with low-level radioactivity measurements for the monitoring of radioactivity in environmental media, such as air and water, in connection with the control of radioactive effluents associated with the production of nuclear power or the use of radionuclides. Included in appendices are nuclear decay data for selected radionuclides and statistics of radioactive decay. An extensive bibliography is also included

Present status of decommissioning in the Musashi Reactor Facility (4)

International Nuclear Information System (INIS)

Uchiyama, Takafumi; Tanzawa, Tomio; Mitsuhashi, Ishi; Morishima, Kayoko; Matsumoto, Tetsuo

2012-01-01

The decommissioning of the Musashi reactor was decided in 2003. Permanent shutdown of the reactor and stopping the operational functions were conducted in 2004. Transportation of the spent fuels was finished in 2006. After 2007, the system and equipment stopping the functions were stored as installed in the reactor facility as radioactive wastes. After separating nonradioactive wastes such as concretes from radioactive wastes with a contamination test, stopping the functions of liquid waste management facility was performed with newly installed drainage facility for radioisotope use in 2010. Solid waste management facility was also dismantled and removed in the same way as liquid waste management facility in 2011. Radioactive wastes packed in containers were moved and stored in the reactor facility. (T. Tanaka)

Fast reactors and nonproliferation

International Nuclear Information System (INIS)

Orlov, V.V.

1997-01-01

1.Three aspects of nonproliferation relevant to nuclear power are: Pu buildup in NPP spent fuel cooling ponds (∼ 104 t in case of consumption of ∼ 107 t cheap uranium). Danger of illegal radiochemical extraction of Pu for weapons production; Pu extraction from NPP fuel at the plants available in nuclear countries, its burning along with weapon-grade Pu in NPP reactors or in special-purpose burners; increased hazard of nuclear weapons sprawl with breeders and closed fuel cycle technology spreading all over the world. 2.The latter is one of major obstacles to creation of large-scale nuclear power. 3.Nuclear power of the first stage using 235 U will be able to meet the demands of certain fuel-deficient countries and regions, replacing ∼ 5-10% of conventional fuels in the global consumption for a number of decades. 4.Fast reactors of the first generation and the currently employed fuel technology are far from exhausting their potential for solving economic problems and meeting the challenges of safety, radioactive waste and nonproliferation. Development of large-scale nuclear power will become an option accepted by society for solving energy problems in the following century, provided a breeder technology is elaborated and demonstrated in the next 15-20 years, which would comply with the totality of the following requirement: full internal Pu breeding deterministic elimination of severe accidents involving fuel damage and high radioactivity releases: fast runaway, loss of coolant, fires, steam and hydrogen explosions, etc.; reaching a balance between radioactive wastes disposed of and uranium mined in terms of radiation hazard; technology of closed fuel cycle preventing its use for Pu extraction and permitting physical protection from fuel thefts;economic competitiveness of nuclear power for most of countries and regions, i.e. primarily the cost of NPPs with fat reactors is to be below the cost of modern LWR plants, etc

Maximum permissible dietary contamination after the accidental release of radioactive materials from a nuclear reactor

Energy Technology Data Exchange (ETDEWEB)

Pochin, E E; Rock Carling, Ernest; Court Brown, W M [Medical Research Council, Committee on Protection against Ionizing Radiations, London (United Kingdom); and others

1960-12-01

After the accident to No. 1 pile at Windscale on October 10, 1957 (Atomic Energy Office, 1957), the Atomic Energy Authority asked the Medical Research Council for advice on the maximum intake of certain radioactive isotopes that should be regarded as permissible, under emergency conditions, for members of the general population living in, or deriving food from, an area contaminated owing to an accident to a reactor. The Council's Committee on Protection against Ionizing Radiations, together with its Subcommittees on Internal and External Radiations, has considered this problem, and concludes that the intake of radioactive materials by ingestion of contaminated food would generally be the limiting source of hazard after any such accident. Intake by inhalation, or radiation from the exterior, would become of importance only in rather special circumstances. In the following report, therefore, the Committee proposes maximum permissible levels of dietary contamination for the relevant isotopes in the emergency conditions envisaged. In proposing these levels, the Protection Committee has used the fullest information available on the radiation doses that would be delivered to different body tissues and at different ages by the isotopes concerned, and on the ways in which these materials would enter the body.

Maximum permissible dietary contamination after the accidental release of radioactive materials from a nuclear reactor

International Nuclear Information System (INIS)

Pochin, E.E.; Rock Carling, Ernest; Court Brown, W.M.

1960-01-01

After the accident to No. 1 pile at Windscale on October 10, 1957 (Atomic Energy Office, 1957), the Atomic Energy Authority asked the Medical Research Council for advice on the maximum intake of certain radioactive isotopes that should be regarded as permissible, under emergency conditions, for members of the general population living in, or deriving food from, an area contaminated owing to an accident to a reactor. The Council's Committee on Protection against Ionizing Radiations, together with its Subcommittees on Internal and External Radiations, has considered this problem, and concludes that the intake of radioactive materials by ingestion of contaminated food would generally be the limiting source of hazard after any such accident. Intake by inhalation, or radiation from the exterior, would become of importance only in rather special circumstances. In the following report, therefore, the Committee proposes maximum permissible levels of dietary contamination for the relevant isotopes in the emergency conditions envisaged. In proposing these levels, the Protection Committee has used the fullest information available on the radiation doses that would be delivered to different body tissues and at different ages by the isotopes concerned, and on the ways in which these materials would enter the body

Decontamination of soil from the research reactor site

International Nuclear Information System (INIS)

Won, H. Z.; Kim, K. N.; Choi, W. K.; Jeong, J. H.; Oh, W. J.

2002-01-01

The two research reactors (TRIGA MARK II and III) in Korea are to be decommissioned in the near future. When the reactors are completely dismantled, the site may remain contaminated due to the long period of operation. We assume that the site is radioactively contaminated by Co-60. Soils gathered from the research reactor site were artificially contaminated with Co 2+ ion. The desorption characteristics of Co 2+ ion from the soil surface by citric acid solution were investigated. Decontamination performances of citric acid and EDTA on soil stored in the radioactive waste drums was examined. The feasibility test of recycling the citric acid was also performed. We concluded that the radioactive waste volume could be reduced significantly by soil washing with a citric acid solution

On present situation of radioactive waste management and exposure of workers in nuclear reactor facilities for commercial power generation in fiscal 1988

International Nuclear Information System (INIS)

1989-01-01

The article summarizes the contents of some reports including the Report on Radiation Management in 1988 that were submitted by the operators of nuclear reactor facilities for commercial power generation according to the requirements specified in the Law Concerning Regulation on Nuclear Material, Nuclear Fuel and Nuclear Reactor. According to these reports, the annual radiation release in all nuclear power generation plants was well below the radiation release limits set up in the report 'On Guidelines for Target Dose in Areas around Light Water Reactor Facilities for Power Generation'. Data submitted also show that there are no significant problems with the management of radioactive solid waste. In all nuclear generation plants, the personal exposure of workers is below the permissible exposure dose specified in law. The Agency of Natural Resources and Energy is planned to further promote the development of advanced techniques for automatization and remote control of light water reactors and to provide effective guidance to electrical contractors for positive radiation management. (N.K.)

Induced structural radioactivity inventory analysis of the base case aqueous ATW reactor concept

International Nuclear Information System (INIS)

Bezdecny, J.A.; Henderson, D.L.; Sailor, W.C.

1993-01-01

The purpose of the Los Alamos National Laboratory Accelerator Transmutation of Nuclear Waste (ATW) project is the substantial reduction in volume of this country's long-lived high-level radioactive waste in a safe and energy efficient manner. An evaluation of the Accelerator Transmutation of Nuclear Waste concept has four aspects; material balance, energy balance, performance and cost. An evaluation of the material balance compares the amount of long-lived high-level waste transmuted with the amount and type of waste created in the process. One component of the material balance is the activation of structural materials over the lifetime of the transmutation reactor. An activation analysis has been performed on four structure regions of the reaction vessel: the tungsten target; the lead target and annulus; the Zircalloy and aluminum tubing carrying the actinide slurry and; the stainless steel tank

Status of the Japan's regulatory policy on radioactive waste management. Cleanup and recycling issues

International Nuclear Information System (INIS)

Takeuchi, Daiji

1995-01-01

Wastes from nuclear facilities are very diversified concerning that have different levels of radioactivity and include different kinds of radioactive materials. Besides some of those waste is not assumed as radioactive waste. The basic policy of the radioactive waste management is taking that diversity into full account for appropriate separate management of different types of radioactive waste and treatment and disposal of each type in a rational manner, including recycling. From the point, the disposal methods are considered or under consideration to that waste, (1) from nuclear reactor facility, (2) from nuclear fuel cycle facility--HLW, waste contaminated TRU nuclides, or contaminated uranium, (3) from RI utilization or research institute, and (4) from decommissioning of nuclear facility. Now in Japan, regulation framework for some kind of LLW from reactor facility, including waste from decommissioning of reactor is established. (J.P.N.)

CEGB's radioactive waste management strategy

International Nuclear Information System (INIS)

Passant, F.H.; Maul, P.R.

1989-01-01

The Central Electricity Generating Board (CEGB) produces low-level and intermediate-level radioactive wastes in the process of operating its eight Magnox and five Advanced Gas Cooled Reactor (AGR) nuclear power stations. Future wastes will also arise from a programme of Pressurised Water Reactors (PWRs) and the decommissioning of existing reactors. The paper gives details of how the UK waste management strategy is put into practice by the CEGB, and how general waste management principles are developed into strategies for particular waste streams. (author)

Safety analysis of RA reactor operation, I-III, Part III - Environmental effect of the maximum credible accident

International Nuclear Information System (INIS)

Raisic, N.

1963-02-01

Maximum credible accident at the RA reactor would consider release of fission products into the environment. This would result from fuel elements failure or meltdown due to loss of coolant. The analysis presented in this report assumes that the reactor was operating at nominal power at the moment of maximum possible accident. The report includes calculations of fission products activity at the moment of accident, total activity release during the accident, concentration of radioactive material in the air in the reactor neighbourhood, and the analysis of accident environmental effects

Disposal strategies and radioactive waste management in surrounding of SR Yugoslavia

International Nuclear Information System (INIS)

Plecas, B.I.

2000-01-01

As of the end 1996, 18 countries in Europe had electricity-generating nuclear power reactors in operation or under construction. There are currently 217 operating units, with a total capacity of about 165 GWe. In addition, there are 26 units under construction, which would bring the total electrical generation capacity to about 190 GWe. Generating electrical power, whether the energy source is coal, oil or nuclear, results in a by-product. In the case of nuclear power, the by-product of concern is radioactive waste. Waste management disposal policy in surroundings countries are presented in this paper (author)

A literature survey for the ultrasound use in the radioactive waste characterization

International Nuclear Information System (INIS)

Tessaro, Ana Paula Gimenes; Vicente, Roberto

2013-01-01

This paper presents the outcomes of a literature survey of reports on the use of ultrasound methods in the characterization of radioactive wastes. This research is motivated by the necessity to characterize radioactive wastes constituted of ion exchange resins and activated charcoal beds generated at the nuclear research reactor IEA-R1 and that are stored in twenty one 200 L-drum sat the Waste Management Department. These two waste types come from the water polishing system of the nuclear reactor where they are used to remove impurities as fission and activation products from the water. After same time in the water treatment system, these two adsorbents are unable to keep the water quality and are then replaced becoming radioactive waste. Previous work determined the concentration of radio isotopes in dried samples of the adsorbents. As the water content varies largely among different drums, it is necessary to determine the water content of each individual drum for the total activity to be calculated. Ultrasound imaging was thought as an appropriate tool as a characterization method. The different acoustic impedances of liquids and solid salter the propagation of the sound wave sand can disclose the content of the waste packages. (author)

A literature survey for the ultrasound use in the radioactive waste characterization

Energy Technology Data Exchange (ETDEWEB)

Tessaro, Ana Paula Gimenes; Vicente, Roberto, E-mail: aptessaro@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

This paper presents the outcomes of a literature survey of reports on the use of ultrasound methods in the characterization of radioactive wastes. This research is motivated by the necessity to characterize radioactive wastes constituted of ion exchange resins and activated charcoal beds generated at the nuclear research reactor IEA-R1 and that are stored in twenty one 200 L-drum sat the Waste Management Department. These two waste types come from the water polishing system of the nuclear reactor where they are used to remove impurities as fission and activation products from the water. After same time in the water treatment system, these two adsorbents are unable to keep the water quality and are then replaced becoming radioactive waste. Previous work determined the concentration of radio isotopes in dried samples of the adsorbents. As the water content varies largely among different drums, it is necessary to determine the water content of each individual drum for the total activity to be calculated. Ultrasound imaging was thought as an appropriate tool as a characterization method. The different acoustic impedances of liquids and solid salter the propagation of the sound wave sand can disclose the content of the waste packages. (author)

Probability safety assessment of LOOP accident to molten salt reactor

International Nuclear Information System (INIS)

Mei Mudan; Shao Shiwei; Yu Zhizhen; Chen Kun; Zuo Jiaxu

2013-01-01

Background: Loss of offsite power (LOOP) is a possible accident to any type of reactor, and this accident can reflect the main idea of reactor safety design. Therefore, it is very important to conduct a study on probabilistic safety assessment (PSA) of the molten salt reactor that is under LOOP circumstance. Purpose: The aim is to calculate the release frequency of molten salt radioactive material to the core caused by LOOP, and find out the biggest contributor to causing the radioactive release frequency. Methods: We carried out the PSA analysis of the LOOP using the PSA process risk spectrum, and assumed that the primary circuit had no valve and equipment reliability data based on the existing mature power plant equipment reliability data. Results: Through the PSA analysis, we got the accident sequences of the release of radioactive material to the core caused by LOOP and its frequency. The results show that the release frequency of molten salt radioactive material to the core caused by LOOP is about 2×10 -11 /(reactor ·year), which is far below that of the AP1000 LOOP. In addition, through the quantitative analysis, we obtained the point estimation and interval estimation of uncertainty analysis, and found that the biggest contributor to cause the release frequency of radioactive material to the core is the reactor cavity cooling function failure. Conclusion: This study provides effective help for the design and improvement of the following molten salt reactor system. (authors)

Nuclear power reactors: reactor safety and military and civil defence

International Nuclear Information System (INIS)

Hvinden, T.

1976-01-01

The formation of fission products and plutonium in reactors is briefly described, followed by a short general discussion of reactor safety. The interaction of reactor safety and radioactive release considerations with military and civil defence is thereafter discussed. Reactors and other nuclear plants are factors which must be taken into account in the defence of the district around the site, and as potential targets of both conventional and guerilla attacks and sabotage, requiring special defence. The radiological hazards arising from serious damage to a power reactor by conventional weapons are briefly discussed, and the benefits of underground siting evaluated. Finally the author discusses the significance of the IAEA safeguards work as a preventive factor. (JIW)

Radioactive waste management in France

International Nuclear Information System (INIS)

Pradel, J.

1975-01-01

The different stages of radioactive waste production are examined: ore production, reactor operation, reprocessing plants. The treatment and storage methods used and the French realizations relative to these problems are described [fr

Low-level radioactive waste management. Background paper

International Nuclear Information System (INIS)

Fawcett, R.

1993-11-01

The management of radioactive waste is one of the most serious environmental problems facing Canadians. From the early industrial uses of radioactive material in the 1930s to the development of nuclear power reactors and the medical and experimental use of radioisotopes today, there has been a steady accumulation of waste products. Although the difficulties involved in radioactive waste management are considerable, responsible solutions are possible. This paper will discuss low-level radioactive waste, including its production, the amounts in storage, the rate of waste accumulation and possible strategies for its management. (author). 2 figs

3. Research Coordination Meeting (RCM) of the Coordinated Research Project (CRP) on 'Studies of advanced reactor technology options for effective incineration of radioactive waste'. Working material

International Nuclear Information System (INIS)

2007-01-01

To meet expressed Member States' needs, the IAEA has initiated a Coordinated Research Project (CRP) on 'Studies of Advanced Reactor Technology Options for Effective Incineration of Radioactive Waste'. The final goal of the CRP is to deepen the understanding of the dynamics of transmutation systems, e.g. the accelerator driven system, especially systems with deteriorated safety parameters, qualify the available methods, specify the range of validity of methods, and formulate requirements for future theoretical developments. Should transient experiments be available, the CRP will pursue experimental benchmarking work. In any case, based on the results, the CRP will conclude on the potential need of transient experiments and make appropriate proposals for experimental programs. The Technical Meeting in Chennai was the 3rd Research Coordination Meeting (RCM) of the CRP The man objectives of the RCM were to: - Discuss and perform inter-comparisons of the various benchmark results; - Prepare the first draft of the final CRP Report Status of the analyses and inter-comparisons of the results. The main objective of the CRP was to study innovative technology options for incinerating/utilizing radioactive wastes. The CRP's benchmarking exercises focused on eight innovative transmutation 'Domains', which correspond to different critical and sub-critical concepts or groups of concepts: I. Critical fast reactor, solid fuel, with fertile; II. Critical fast reactor, solid fuel, fertile-free; III. ADS, solid fuel, with fertile; IV. ADS, solid fuel, fertile-free; V. Critical reactor and ADS, molten salt fuel, with fertile; VI. Critical reactor and ADS, molten salt fuel, fertile-free; VII. Critical fast reactor and ADS, gas cooled; VIII. Fusion/fission hybrid system. For each of these Domains, the discussions and inter-comparisons considered the following issues: - Reactor-models; - Scenarios/phenomena; - Static analyses; - Dynamic analyses; - Methods; - Codes; - Neutronic data base

The Waste Management Plan integration into Decommissioning Plan of the WWR-S research reactor from Romania

International Nuclear Information System (INIS)

Barariu, Gheorghe; Oprescu, Theodor; Filip, Mihaela; Sociu, Florin

2008-01-01

The paper presents the progress of the Radioactive Waste Management Plan which accompanies the Decommissioning Plan for research reactor WWR-S located in Magurele, Ilfov, near Bucharest, Romania. The new variant of the Decommissioning Plan was elaborated taking into account the IAEA recommendation concerning radioactive waste management. A new feasibility study for WWR-S decommissioning was also developed. The preferred safe management strategy for radioactive wastes produced by reactor decommissioning is outlined. The strategy must account for reactor decommissioning, as well as rehabilitation of the existing Radioactive Waste Treatment Plant and the upgrade of the Radioactive Waste Disposal Facility at Baita-Bihor. Furthermore, the final rehabilitation of the laboratories and reusing of cleaned reactor building is envisaged. An inventory of each type of radioactive waste is presented. The proposed waste management strategy is selected in accordance with the IAEA assistance. Environmental concerns are part of the radioactive waste management strategy. (authors)

Management of radioactive waste from reprocessing plants

International Nuclear Information System (INIS)

Kanwar Raj

2010-01-01

Reprocessing and recycling of both fissile and fertile components back into appropriate reactor systems is an integral part of three stage nuclear energy programme of India. Different steps involved in processing of spent nuclear fuel (SNF) are decladding, dissolution and recovery of fissile and fertile materials. Reprocessing of SNF is a complex process involving handling of large quantity of radioactive materials and processing chemicals. There are three reprocessing plants in operation in the country at Trombay, Tarapur and Kalpakkam. Out of these plants, Trombay reprocessing plant is engaged in reprocessing of SNF from research reactors and other two plants are processing of SNF from PHWRs. A facility is being built for reprocessing of thorium based spent fuel at BARC, Trombay based on the experience of pilot plant scale. Like other industrial activities of nuclear fuel cycle, fuel reprocessing facilities too generate various types of radioactive waste streams. These are generated in all the three physical forms namely solid, liquid and gas. These waste streams are primarily categorized on the basis of concentration of radionuclides, their half lives and toxicity. Management of these wastes aims at (a) recovery and recycle of useful materials, (b) concentration and confinement of radioactivity in inert and stable matrices, (c) minimization of final waste volume for disposal, (d) decontamination of effluents following ALARA principle and (e) minimization of radioactive discharge to the environment. The present paper outlines the salient features of management of different types of radioactive waste generated in reprocessing plants handling SNF from research reactors and PHWR

Radioactivity of spent TRIGA fuel

International Nuclear Information System (INIS)

Usang, M. D.; Nabil, A. R. A.; Alfred, S. L.; Hamzah, N. S.; Abi, M. J. B.; Rawi, M. Z. M.; Abu, M. P.

2015-01-01

Some of the oldest TRIGA fuel in the Malaysian Reaktor TRIGA PUSPATI (RTP) is approaching the limit of its end of life with burn-up of around 20%. Hence it is prudent for us to start planning on the replacement of the fuel in the reactor and other derivative activities associated with it. In this regard, we need to understand all of the risk associated with such operation and one of them is to predict the radioactivity of the fuel, so as to estimate the safety of our working conditions. The radioactivity of several fuels are measured and compared with simulation results to confirm the burnup levels of the selected fuels. The radioactivity measurement are conducted inside the water tank to reduce the risk of exposure and in this case the detector wrapped in plastics are lowered under water. In nuclear power plant, the general practice was to continuously burn the fuel. In research reactor, most operations are based on the immediate needs of the reactor and our RTP for example operate periodically. By integrating the burnup contribution for each core configuration, we simplify the simulation of burn up for each core configuration. Our results for two (2) fuel however indicates that the dose from simulation underestimate the actual dose from our measurements. Several postulates are investigated but the underlying reason remain inconclusive

Radioactivity of spent TRIGA fuel

Energy Technology Data Exchange (ETDEWEB)

Usang, M. D., E-mail: mark-dennis@nuclearmalaysia.gov.my; Nabil, A. R. A.; Alfred, S. L.; Hamzah, N. S.; Abi, M. J. B.; Rawi, M. Z. M.; Abu, M. P. [Reactor Department, Malaysian Nuclear Agency, Bangi, 43000 Kajang, Selangor (Malaysia)

2015-04-29

Some of the oldest TRIGA fuel in the Malaysian Reaktor TRIGA PUSPATI (RTP) is approaching the limit of its end of life with burn-up of around 20%. Hence it is prudent for us to start planning on the replacement of the fuel in the reactor and other derivative activities associated with it. In this regard, we need to understand all of the risk associated with such operation and one of them is to predict the radioactivity of the fuel, so as to estimate the safety of our working conditions. The radioactivity of several fuels are measured and compared with simulation results to confirm the burnup levels of the selected fuels. The radioactivity measurement are conducted inside the water tank to reduce the risk of exposure and in this case the detector wrapped in plastics are lowered under water. In nuclear power plant, the general practice was to continuously burn the fuel. In research reactor, most operations are based on the immediate needs of the reactor and our RTP for example operate periodically. By integrating the burnup contribution for each core configuration, we simplify the simulation of burn up for each core configuration. Our results for two (2) fuel however indicates that the dose from simulation underestimate the actual dose from our measurements. Several postulates are investigated but the underlying reason remain inconclusive.

New approach to neutron-induced transmutation, radioactivity and afterheat calculations and its application to fusion reactors

International Nuclear Information System (INIS)

Fukumoto, Hideshi

1986-01-01

A new method and an accompanying computer code CINAC have been developed for the calculation of neutron-induced transmutation, radioactivity and afterheat. In the method, the generation and depletion of nuclides during and after reactor operation are described in a matrix form in which the arrangement of nuclides is determined systematically. The solutions are obtained by an eigenvalue analysis of the matrix without any time steps or iterative schemes which would increase the computational time. The method can treat any type of activation chains equally, and it gives analytical solutions for linear chains. The CINAC code, coupled with the radiation transport codes ANISN and DOT3.5, can also calculate the dose distribution at any time after shutdown in a one- or two-dimensional geometry of fusion reactors. Two calculations were carried out using CINAC to confirm its validity. The results were compared to those calculated by the THIDA code system which is based on a matrix exponential method. The new method was 50 times faster than the latter, while the discrepancy between them was 4 % at the most. (author)

Current status of radioactive waste management (RWM) in Thailand

International Nuclear Information System (INIS)

Chantaraprachoom, N.

2003-01-01

Radioactive wastes in Thailand are mainly from the nuclear application in medicine, industry, agriculture, education and research reactor operation. The quantities of radioactive waste each year are relatively small. About 90 m 3 of processed waste and 7 m 3 unprocessed wastes are now stored at the waste storage facilities in the OAP. Recently the regulation on radioactive waste management was drafted and proposed to the cabinet for approval and to be promulgated as a ministerial regulation. A new nuclear research center, r which comprises 10 MW Research Reactor, Radioisotope Production and Centralized Waste Processing and Storage Facilities, is to be established at Ongkarak district in Nakornnayok province in the future. (author)

Disposal of high-level radioactive waste

International Nuclear Information System (INIS)

Glasby, G.P.

1977-01-01

Although controversy surrounding the possible introduction of nuclear power into New Zealand has raised many points including radiation hazards, reactor safety, capital costs, sources of uranium and earthquake risks on the one hand versus energy conservation and alternative sources of energy on the other, one problem remains paramount and is of global significance - the storage and dumping of the high-level radioactive wastes of the reactor core. The generation of abundant supplies of energy now in return for the storage of these long-lived highly radioactive wastes has been dubbed the so-called Faustian bargain. This article discusses the growth of the nuclear industry and its implications to high-level waste disposal particularly in the deep-sea bed. (auth.)

Technical feasibility study on volumetric reduction of radioactive wastes using plasma technology

Energy Technology Data Exchange (ETDEWEB)

Prado, E.S.P.; Dellamano, J.C.; Carneiro, A.L.G.; Santos, R.C.; Potiens Junior, A.J. [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil); Petraconi, G., E-mail: edu.petraconi@usp.br [Instituto Tecnológico da Aeronáutica (ITA), São José dos Campos, SP (Brazil)

2017-07-01

The radioactive waste arising from nuclear reactors, hospitals, industry and research institutes are generated daily with a considerable amount. To final dispose of these radioactive waste safely and cost effectively, they must be transformed into physical and chemical compounds suitable for radionuclides immobilization with maximum volume and exhaust gaseous reduction. In this scope, among the promising technologies for the radioactive waste treatment, plasma technology allows reducing substantially the waste volume after exposing them to temperatures above 2,500 deg C. In the planning and management of radioactive waste, the challenges related to plasma technology are presented as a motivation factor for the possible implantation of plasma reactors in nuclear plants and research centers aiming at improving the process of radioactive waste management. (author)

Technical feasibility study on volumetric reduction of radioactive wastes using plasma technology

International Nuclear Information System (INIS)

Prado, E.S.P.; Dellamano, J.C.; Carneiro, A.L.G.; Santos, R.C.; Potiens Junior, A.J.; Petraconi, G.

2017-01-01

The radioactive waste arising from nuclear reactors, hospitals, industry and research institutes are generated daily with a considerable amount. To final dispose of these radioactive waste safely and cost effectively, they must be transformed into physical and chemical compounds suitable for radionuclides immobilization with maximum volume and exhaust gaseous reduction. In this scope, among the promising technologies for the radioactive waste treatment, plasma technology allows reducing substantially the waste volume after exposing them to temperatures above 2,500 deg C. In the planning and management of radioactive waste, the challenges related to plasma technology are presented as a motivation factor for the possible implantation of plasma reactors in nuclear plants and research centers aiming at improving the process of radioactive waste management. (author)

New design targets and new automated technology for the production of radionuclides with high specificity radioactivity in nuclear research reactors

International Nuclear Information System (INIS)

Gerasimov, A.S.; Kiselev, G.V.

1997-01-01

Current demands of industry require the application of radionuclides with high specific radioactivity under low consumption of neutrons. To provide this aim staff of ITEP Reactor Department investigated the different type AEs of start targets for the production of the main radionuclides; Co-60, Ir-192 and others. In first turn the targets of Co and Ir without the block-effect of neutron flux (with low absorption of neutrons) were investigated. The following principal results were received for example for Ir-192: block effect is equal 0.086 for diameter of Ir target mm and is equal 0.615 for diameter Ir target 0.5mm. It means average neutron flux for Ir target diameter 0.5mm and therefore the production of Ir-192 will be at 10 times more than for diameter 6.0mm. To provide the automated technology of the manufacture of radioactive sources with radionuclides with high specific radioactivity it was proposed that the compound targets for the irradiation of ones and for the management with the irradiated targets. Different types of compound targets were analyzed. (authors)

Releases of radioactive substances from Swedish nuclear power plants (RAKU)

Energy Technology Data Exchange (ETDEWEB)

Ingemansson, T.; Bergstroem, C. [ALARA Engineering AB, Skultuna (Sweden)

1997-04-01

Releases of radioactivity to air and water from Swedish nuclear power plants have been studied and compared with those from foreign reactors. Averaged over the years from commissioning of the reactors to the last year data are available, the release of radioactive noble gas from the Swedish BWRs has been about the same as from comparable foreign reactors. The oldest Swedish BWRs, Oskarshamn 1 and 2 (O1 and O2) and Ringhals 1 (R1), have simple off-gas systems with only one delay volume. All BWRs in US, Germany, Japan and Switzerland are equipped with more sophisticated off-gas systems. It can be expected that O1, O2 and R1 therefore will have the highest release of noble gas activity at an international comparison if they do not modernize their off-gas system. BWRs in US, Germany and Japan are today equipped with recombiners and with one exception also charcoal columns. Japanese BWRs report zero releases to air. Releases of radioactivity to water after commissioning was about the same for most of the studied reactors. Some of the newest German plants have had low annual releases already at commissioning. Improvements of the treatment systems at old German, Swiss and US reactors have significantly lowered the releases. For most of the Swedish plants the annual releases to water have remained at the initial level. Forsmark 3 has succeeded in decreasing the release of radionuclides to water by a factor of almost one hundred compared to other Swedish reactors. Also O3 has managed to decrease the liquid effluents. Japanese plants have zero release of radioactivity excluding tritium to water. The release of tritium is about the same for all reactors of the same type in the world. 35 refs, 31 figs, 24 tabs.

Nuclear reactor safety research since Three Mile Island

International Nuclear Information System (INIS)

Mynatt, F.R.

1982-01-01

The Three Mile Island nuclear power plant accident has resulted in redirection of reactor safety research priorities. The small release to the environment of radioactive iodine-13 to 17 curies in a total radioactivity release of 2.4 million to 13 million curies-has led to a new emphasis on the physical chemistry of fission product behavior in accidents; the fact that the nuclear core was severely damaged but did not melt down has opened a new accident regime-that of the degraded core; the role of the operators in the progression and severity of the accident has shifted emphasis from equipment reliability to human reliability. As research progresses in these areas, the technical base for regulation and risk analysis will change substantially

Nuclear reactor safety research since three mile island.

Science.gov (United States)

Mynatt, F R

1982-04-09

The Three Mile Island nuclear power plant accident has resulted in redirection of reactor safety research priorities. The small release to the environment of radioactive iodine-13 to 17 curies in a total radioactivity release of 2.4 million to 13 million curies-has led to a new emphasis on the physical chemistry of fission product behavior in accidents; the fact that the nuclear core was severely damaged but did not melt down has opened a new accident regime-that of the degraded core; the role of the operators in the progression and severity of the accident has shifted emphasis from equipment reliability to human reliability. As research progresses in these areas, the technical base for regulation and risk analysis will change substantially.

Reactor as furnace and reactor as lamp

International Nuclear Information System (INIS)

Goldanskii, V.I.

1992-01-01

There are presented general characteristics of the following ways of transforming of nuclear energy released in reactors into chemical : ordinary way (i.e. trough the heat, mechanical energy and electricity); chemonuclear synthesis ; use of high-temperature fuel elements (reactor as furnace); use of the mixed nγ-radiation of reactors; use of the radiation loops; radiation - photochemical synthesis (reactor as lamp). Advantage and disadvantages of all above variants are compared. The yield of the primary product of fixation of nitrogen (nitric oxide NO) in reactor with the high-temperature (above ca. 1900degC) fuel elements (reactor-furnace) can exceed W ∼ 200 kg per gram of burned uranium. For the latter variant (reactor-lamp) the yield of chemical products can reach W ∼ 60 kg. per gram of uranium. Such values of W are close to or even strongly exceed the yields of chemical products for other abovementioned variants and - what is particularly important - are not connected to the necessity of archscrupulous removal of radioactive contamination of products. (author)

MEANS FOR SHIELDING AND COOLING REACTORS

Science.gov (United States)

Wigner, E.P.; Ohlinger, L.A.; Young, G.J.; Weinberg, A.M.

1959-02-10

Reactors of the water-cooled type and a means for shielding such a rcactor to protect operating personnel from harmful radiation are discussed. In this reactor coolant tubes which contain the fissionable material extend vertically through a mass of moderator. Liquid coolant enters through the bottom of the coolant tubes and passes upwardly over the fissionable material. A shield tank is disposed over the top of the reactor and communicates through its bottom with the upper end of the coolant tubes. A hydrocarbon shielding fluid floats on the coolant within the shield tank. With this arrangements the upper face of the reactor can be opened to the atmosphere through the two superimposed liquid layers. A principal feature of the invention is that in the event radioactive fission products enter thc coolant stream. imposed layer of hydrocarbon reduces the intense radioactivity introduced into the layer over the reactors and permits removal of the offending fuel material by personnel shielded by the uncontaminated hydrocarbon layer.

Reactor accidents and the environment

International Nuclear Information System (INIS)

Beattie, J.R.; Griffiths, R.F.; Kaiser, G.D.; Kinchin, G.H.

1978-01-01

This is a condensed version of a paper, entitled 'The Environmental Impact of Radioactive Releases from Accidents in Nuclear Power Reactors', by the authors, presented to the Nuclear Energy Panel of the International Atomic Energy Agency/United Nations Environmental Programme. Headings include - Effects of ionising radiation on man; number of deaths expected from leukaemia and other cancers; risk estimates for incidence of benign nodules and thyroid cancer; maximum permissible levels and emergency levels of radiation and radioactivity; ICRP recommended dose limits for members of the general public; atmospheric dispersion and modelling; ICRP emergency reference levels for 1 131 , Cs 137 , Ru 106 and Sr 90 ; environmental consequences of accidental releases from nuclear power reactors; environmental impact of accidents to Magnox gas-cooled reactors; environmental impact of accidents to advanced gas-cooled reactors; environmental impact of accidents to fast reactors; and nature of risks. consequences are examined in terms of early and late biological effects on man, and contamination of land areas. Serious accidents are of low probability of occurrence, and the risk of accidents to nuclear power reactors is estimated to be very small. 43 references. (U.K.)

Radioactivities evaluation code system for high temperature gas cooled reactors during normal operation

International Nuclear Information System (INIS)

Ogura, Kenji; Morimoto, Toshio; Suzuki, Katsuo.

1979-01-01

A radioactivity evaluation code system for high temperature gas-cooled reactors during normal operation was developed to study the behavior of fission products (FP) in the plants. The system consists of a code for the calculation of diffusion of FPs in fuel (FIPERX), a code for the deposition of FPs in primary cooling system (PLATO), a code for the transfer and emission of FPs in nuclear power plants (FIPPI-2), and a code for the exposure dose due to emitted FPs (FEDOSE). The FIPERX code can calculate the changes in the course of time FP of the distribution of FP concentration, the distribution of FP flow, the distribution of FP partial pressure, and the emission rate of FP into coolant. The amount of deposition of FPs and their distribution in primary cooling system can be evaluated by the PLATO code. The FIPPI-2 code can be used for the estimation of the amount of FPs in nuclear power plants and the amount of emitted FPs from the plants. The exposure dose of residents around nuclear power plants in case of the operation of the plants is calculated by the FEDOSE code. This code evaluates the dose due to the external exposure in the normal operation and in the accident, and the internal dose by the inhalation of radioactive plume and foods. Further studies of this code system by the comparison with the experimental data are considered. (Kato, T.)

Longtime radionuclide monitoring in the vicinity of Salaspils nuclear reactor

International Nuclear Information System (INIS)

Riekstina, D.; Berzins, J.; Krasta, T.; Skrypnik, O.; Alksnis, J.

2016-01-01

The research nuclear reactor in Salaspils was decommissioned in 1998. Now reactor is partially dismantled and its territory is used as a temporary storage of radioactivity contaminated materials and water. Environment radioactivity monitoring for presence of artificial radionuclides in the vicinity of Salaspils nuclear reactor is carried out since 1990. Data include Cs-137 concentration in soils, tritium concentration in ground water, as well as H-3, Cs-137, Co-60 concentration and gross beta-activity of reactors sewage and rainwater drainage. The systematic monitoring allowed to detect in December 2014 a leakage from the special wastewater basin and so to prevent a pollution of ground water outside reactors territory.

Reactor operation safety information document

Energy Technology Data Exchange (ETDEWEB)

1990-01-01

The report contains a reactor facility description which includes K, P, and L reactor sites, structures, operating systems, engineered safety systems, support systems, and process and effluent monitoring systems; an accident analysis section which includes cooling system anomalies, radioactive materials releases, and anticipated transients without scram; a summary of onsite doses from design basis accidents; severe accident analysis (reactor core disruption); a description of operating contractor organization and emergency planning; and a summary of reactor safety evolution. (MB)

Pressurized heavy-water reactor safety

International Nuclear Information System (INIS)

Pease, L.; Wilson, R.

1977-09-01

CANDU-PWR type reactors routinely release small amounts of radioactive liquids and gases and large quantities of low-grade waste heat. Radioactive emissions are usually below 1% of the derived release limits based on ICRP limits. Waste heat is common to all power plants and is not foreseen as a problem in Canadian conditions. Risk analysis shows a very low accident probability for CANDU type reactors. Multiple barriers to release of radionuclides, quality assurance, control, and inspection, containment systems, the shutdown system, the ECCS, and leak-before-break design, would all combine to mitigate the effects of an accident. (E.C.B.)

A high temperature reactor could be used to eliminate the Russian military plutonium

International Nuclear Information System (INIS)

Foucher, N.

1999-01-01

The GT-MHR reactor (Gas Turbine Modular Helium Reactor) aims the double objective to eliminate the Russian plutonium coming from weapons, ( until 3 tons by year) and to produce a competitive energy from a small-scale power reactor with a nuclear fuel that can be of different type (plutonium or uranium). This reactor has several advantages: a high yield (47%) as every high temperature reactor and to be used in combined cycle, a high level of safety because of its ability to evacuate the residual power in a totally passive way and because of the nature of its fuel that is made of ceramics with a very high melting point that is to say no possibility of core melt. The fission products are contained in the ceramics so that reactor cannot disseminate radioactivity in its structure and consequently does not induce irradiation for the personnel. (N.C.)

Environmental radioactivity in northern parts of Iran and Teheran

International Nuclear Information System (INIS)

Khademi, B.; Hanjani, M.A.

1974-01-01

This article deals with the measurement of the amount of 226Ra by ''radium emanation method'' in water and food products of the North, North-West and North-East of Iran. A total of 126 water samples, 249 food-stuffs and 22 air samples have been examined. The concentration of 226Ra in water was about 0.01 to 1x10 4 pci/1, and in food products was about 0.01 to 20.00 pci/gr. The measured radioactivity in the air for the city of Tehran and Tehran University reactor's environment has been about 0.003 to 0.227 pci/m 3 . The results of these measurements for Iran's atmosphere are given in various tables which indicated that in some part of Iran the rate of the radioactivity is higher than the normal rate

Ignalina RBMK-1500 building capability in retaining radioactive releases

International Nuclear Information System (INIS)

Nilsson, Lars; Johansson, K.

1993-01-01

The Ignalina reactor building structures are capable of retaining substantial fractions of radioactive emissions from the fuel core, in those accident sequences where pressurization failure of structures can be averted by pressure relief arrangements. In stage 1 of the IBBA project it was demonstrated that enhanced retention of radioactive fission products within the plant can be achieved if natural convection is facilitated in the upper building compartments. In this report of stage 2 is discussed for which accident sequences the introduction of natural convection in combination with the existing forced convection ventilation and the accident localization system can improve the total safety of Ignalina 1-2. The purpose of this stage is to provide a basis for further review and more detailed studies of the natural convection concept, its benefits and disadvantages, and of the feasability to introduce the concept in existing plants

Radioactivity and foods

International Nuclear Information System (INIS)

Olszyna-Marzys, A.E.

1991-01-01

The purpose of this article is to describe and contrast two relationships between radiation and food on the one hand, beneficial preservation of food by controlled exposure to ionizing radiation; and, on the other, contamination of food by accidental incorporation of radioactive nuclides within the food itself. In food irradiation, electrons or electromagnetic radiation is used to destroy microorganisms and insects or prevent seed germination. The economic advantages and health benefits of sterilizing food in this manner are clear, and numerous studies have confirmed that under strictly controlled conditions no undesirable changes or induced radioactivity is produced in the irradiated food. An altogether different situation is presented by exposure of food animals and farming areas to radioactive materials, as occurred after the major Soviet nuclear reactor accident at Chernobyl. This article furnishes the basic information needed to understand the nature of food contamination associated with that event and describes the work of international organizations seeking to establish appropriate safe limits for levels of radioactivity in foods

Ventilation system in the RA reactor building - design specifications

International Nuclear Information System (INIS)

Badrljica, R.

1984-09-01

Protective role of the ventilation system of nuclear facilities involve construction of ventilation barriers which prevent release of radioactive particulates or gases, elimination od radioactive particulates and gases from the air which is released from contaminated zones into the reactor environment. Ventilation barriers are created by dividing the building into a number of ventilation zones with different sub pressure compared to the atmospheric pressure. The RA reactor building is divided into four ventilation zones. First zone is the zone of highest risk. It includes reactor core with horizontal experimental channels, underground rooms of the primary coolant system (D 2 O), helium system, hot cells and the space above the the reactor core. Second zone is the reactor hall and the room for irradiated fuel storage. The third zone includes corridors in the basement, ground floor and first floor where the probability of contamination is small. The fourth zone includes the annex where the contamination risk is low. There is no have natural air circulation in the reactor building. Ventilators for air input and outlet maintain the sub pressure in the building (pressure lower than the atmospheric pressure). This prevents release of radioactivity into the atmosphere [sr

Decommissioning and re-utilization of the Musashi Reactor

International Nuclear Information System (INIS)

Tomio Tanzawa; Nobukazu Iijima; Norikazu Horiuchi; Tadashi Yoshida; Tetsuo Matsumoto; Naoto Hagura; Ryouhei Kamiya

2008-01-01

The Musashi Institute of Technology Research Reactor (the Musashi Reactor) is a TRIGA-? with maximum thermal power of 100 kW. The decommissioning was decided in May, 2003. The reactor facility is now under decommissioning. The phased decommissioning was selected. Phase 1 consists of permanent shutdown of the reactor and stopping the operational functions, and transportation of the spent nuclear fuels. After completion of the transportation, the reactor facility is characterized as the storage of low level radioactive materials. This is phase 2. Activities of phase 1 were completed and the facility is now under phase 2. Activities of phase 3 consist of dismantling the reactor tank and the shielding, and delivering the radioactive waste to a waste disposal facility. The phase 3 will be started on condition that the undertaking of the waste disposal for research reactors will be established. On the other hand, re-utilization of the facility has being studied, and 'realistic' reactor simulator was turned out by utilizing the reactor installations such as control rod drive and operation console. (authors)

Characterization of the solid radioactive waste from Cernavoda NPP

International Nuclear Information System (INIS)

Iordache, M.; Lautaru, V.; Bujoreanu, D.

2005-01-01

During the operation of a nuclear plant significant quantities of radioactive waste result that have a very large diversity. At Cernavoda NPP large amounts of wastes are either non-radioactive wastes or radioactive wastes, each of these being managed completely different from each other. For a CANDU type reactor, the occurrence of radioactive wastes is due to contamination with the following types of radioactive substances: - fission products resulting from nuclear fuel burning; - activated products from materials composing the technological systems; - activated products in process fluids. Radioactive wastes can be in solid, liquid or gas form. At Cernavoda NPP the solid wastes represent about 70% of the waste volume which is produced during plant operation and as a consequence of maintenance and decontamination operations. The most important types of solid wastes that are obtained and then handled, processed (if necessary) and temporarily stored are: solid low-level radioactive wastes (classified as compactible and non-compactible), solid medium radioactive wastes, spent resins, used filters and filter cartridges. The liquid radioactive waste class includes organic liquids (used oil, scintillator liquids and used solvents) and aqueous wastes resulting from process system operating, from decontamination and maintenance operations. Radioactive gas wastes occur subsequently to the fission process inside the fuel elements as well as due to the neutron activation of process fluids in the reactor systems. As result of plant operation, iodine, noble gases, tritium and radioactive particles occur and are passed toward the ventilation stack in a controlled manner so that environmental release of radioactive materials with concentrations exceeding the maximum permissible level could not occur. (authors)

Conceptual research on reactor core physics for accelerator driven sub-critical reactor

International Nuclear Information System (INIS)

Zhao Zhixiang; Ding Dazhao; Liu Guisheng; Fan Sheng; Shen Qingbiao; Zhang Baocheng; Tian Ye

2000-01-01

The main properties of reactor core physics are analysed for accelerator driven sub-critical reactor. These properties include the breeding of fission nuclides, the condition of equilibrium, the accumulation of long-lived radioactive wastes, the effect from poison of fission products, as well as the thermal power output and the energy gain for sub-critical reactor. The comparison between thermal and fast system for main properties are carried out. The properties for a thermal-fast coupled system are also analysed

Transport mechanisms of radioactive substances in the Arctic Ocean. Modelling and experimental studies in the Kara and Barents Seas

International Nuclear Information System (INIS)

Nies, H.; Karcher, M.; Bahe, C.; Backhaus, J.; Harms, I.

1999-03-01

In 1992, it became known to the public that the former Soviet Union had dumped large amounts of radioactive waste in the Arctic Ocean since about 1959. The waste was dumped into the Kara and Barents Seas in liquid and solid form, sealed in barrels or containers, as reactor parts but also as complete ship reactors including spent fuel. Wrecks of nuclear submarines were dumped near the coast of Novaya Semlya, in depths less than 50 m. The dumping took place in strong contradiction to international rules and conventions. After some confusion and overestimation of the total radioactive inventory, the amount of the waste and the dump site locations are well known, meanwhile. International pressure and the more open information policy of Russia helped to improve the situation. Various international fora primarily within the IAEA and the Arctic Monitoring and Assessment Programme (AMAP) investigated the potential consequences from these dumping practices. This report is the German contribution to these international assessments. The dumped objects in the Kara Sea encompass 17 nuclear ship reactors, seven of them still carrying spent fuel. Four dump sites are located in small and shallow fjords at the east coast of Novaya Semlya, and in the Novaya Semlya Trough, in max. depth of 420 m. The total radioactive inventory was, at the time of dumping, 37 PBq. During the project numerous samples from seawater and sediment were analysed on artificial radionuclides in Arctic waters. This included samples from the Kara Sea but also samples around the Russian nuclear submarine Komsomolets sunk in the Norwegian Sea at a depth of about 1700 m in 1989. Numerical hydrodynamic models in local, regional and global scale were used to predict the potential dispersion of released radionuclides from the dumped wastes and reactors in the Kara Sea. (orig.) [de

Environmental impact assessment of the nuclear reactor at Vinca, based on the data on emission of radioactivity from the literature: A modeling approach

Directory of Open Access Journals (Sweden)

Gršić Z.

2015-01-01

Full Text Available Research activities of Vinca Institite have been based on two heavy water research reactors: 10 MW one, RA and zero power RB. Reactor RA was operational from 1962 to 1982. In 2010, spent fuel have been sent to the country of origin, and reactor now is in decommissioning. During operational phase of the reactor there were no recorded accidental releases into the environment just operational ones. Results of the environmental impact assessment, of the assumed emission of radionuclides, from the ventilation of nuclear reactor "RA" in Vinca, to the atmospheric boundary layer are presented in this paper. Evaluation was done by using the Gaussian straight-line diffusion model and taking into account characteristics of the reactor ventilation system, the assumed emission release of radioactivity (from the literature, site-specific meteorological data for six-year period and local topography around nuclear reactor, and corresponding dose factors for inventory of radionuclides. Based on the described approach, and assuming that the range of appropriate meteorological data for six year period for the application of described mathematical model is enough for this kind of analysis, it can be concluded that the nuclear reactor "RA", in the course of its work from 1962 to 1982, had no influence on the surrounding environment through the air above regulatory limits. [Projekat Ministarstva nauke Republike Srbije, br. III 45003

Decommissioning a nuclear reactor

International Nuclear Information System (INIS)

Montoya, G.M.

1991-01-01

The process of decommissioning a facility such as a nuclear reactor or reprocessing plant presents many waste management options and concerns. Waste minimization is a primary consideration, along with protecting a personnel and the environment. Waste management is complicated in that both radioactive and chemical hazardous wastes must be dealt with. This paper presents the general decommissioning approach of a recent project at Los Alamos. Included are the following technical objectives: site characterization work that provided a thorough physical, chemical, and radiological assessment of the contamination at the site; demonstration of the safe and cost-effective dismantlement of a highly contaminated and activated nuclear-fuelded reactor; and techniques used in minimizing radioactive and hazardous waste. 12 figs

Method of processing radioactive liquid wastes

International Nuclear Information System (INIS)

Kawamura, Fumio; Funabashi, Kiyomi; Matsuda, Masami.

1984-01-01

Purpose: To improve the performance of removing metal ions in ion exchange resins for use in clean-up of service water or waste water in BWR type reactors. Method: A column filled with activated carbon is disposed at the pre- or post-stage of a clean-up system using ion exchange resins disposed for the clean-up of service water or waste water of a nuclear reactor so that organics contained in water may be removed through adsorption. Since the organic materials are thus adsorbed and eliminated, various types of radioactive ions contained in radioactive liquid are no more masked and the performance of removing ions in the ion exchanger resins of the clean-up device can be improved. (Moriyama, K.)

Radioactivity analysis of KAMINI reactor coolant from regulatory perspectives

International Nuclear Information System (INIS)

Srinivasan, T.K.; Sulthan, Bajeer; Sarangapani, R.; Jose, M.T.; Venkatraman, B.; Thilagam, L.

2016-01-01

KAMINI (a 30kWt) research reactor is operated for neutron radiography of fuel subassemblies and pyro devices and activation analysis of various samples. The reactor is fueled by 233 U and DM water is used as the coolant. During reactor operation, fission product noble gasses (FPNGs) such as 85m Kr, 87 Kr, 88 Kr, 135 Xe, 135m Xe and 138 Xe are detected in the coolant water. In order to detect clad failure, the water is sampled during reactor operation at regular intervals as per the technical specifications. In the present work, analysis of measured activities in coolant samples collected during reactor operation at 25 kWt are presented and compared with computed values obtained using ORIGEN (Isotope Generation) code

Nuclear reactors for space electric power

International Nuclear Information System (INIS)

Buden, D.

1978-06-01

The Los Alamos Scientific Laboratory is studying reactor power plants for space applications in the late 1980s and 1990s. The study is concentrating on high-temperature, compact, fast reactors that can be coupled with various radiation shielding systems and thermoelectric, dynamic, or thermionic electric power conversion systems, depending on the mission. Lifetimes of 7 to 10 yr at full power, at converter operating temperatures of 1275 to 1675 0 K, are being studied. The systems are being designed such that no single-failure modes exist that will cause a complete loss of power. In fact, to meet the long lifetimes, highly redundant design features are being emphasized. Questions have been raised about safety since the COSMOS 954 incident. ''Fail-safe'' means to prevent exposure of the population to radioactive material, meeting the environmental guidelines established by the U.S. Government have been and continue to be a necessary requirement for any space reactor program. The major safety feature to prevent prelaunch and launch radioactive material hazards is not operating the reactor before achieving the prescribed orbit. Design features in the reactor ensure that accidental criticality cannot occur. High orbits (above 400 to 500 nautical miles) have sufficient lifetimes to allow radioactive elements to decay to safe levels. The major proposed applications for satellites with reactors in Earth orbit are in geosynchronous orbit (19,400 nautical miles). In missions at geosynchronous orbit, where orbital lifetimes are practically indefinite, the safety considerations are negligible. Orbits below 400 to 500 nautical miles are the ones where a safety issue is involved in case of satellite malfunction. The potential missions, the question of why reactors are being considered as a prime power candidate, reactor features, and safety considerations will be discussed

Nuclear reactor safety system

International Nuclear Information System (INIS)

Sato, Takashi.

1979-01-01

Purpose: To allow sufficient removal of radioactive substance released in the reactor containment shell upon loss of coolants accidents thus to sufficiently decrease the exposure dose to human body. Constitution: A clean-up system is provided downstream of a heat exchanger and it is branched into a pipeway to be connected to a spray nozzle and further connected by way of a valve to a reactor container. After the end of sudden transient changes upon loss of coolants accidents, the pool water stored in the pressure suppression chamber is purified in the clean-up system and then sprayed in the dry-well by way of a spray nozzle. The sprayed water dissolves to remove water soluble radioactive substances floating in the dry-well and then returns to the pressure suppression chamber. Since radioactive substances in the dry-well can thus removed rapidly and effectively and the pool water can be reused, public hazard can also be decreased. (Horiuchi, T.)

Decommissioning of reactor facilities (2). Required technology

International Nuclear Information System (INIS)

Yanagihara, Satoshi

2014-01-01

Decommissioning of reactor facilities was planned to perform progressive dismantling, decontamination and radioactive waste disposal with combination of required technology in a safe and economic way. This article outlined required technology for decommissioning as follows: (1) evaluation of kinds and amounts of residual radioactivity of reactor facilities with calculation and measurement, (2) decontamination technology of metal components and concrete structures so as to reduce worker's exposure and production of radioactive wastes during dismantling, (3) dismantling technology of metal components and concrete structures such as plasma arc cutting, band saw cutting and controlled demolition with mostly remote control operation, (3) radioactive waste disposal for volume reduction and reuse, and (4) project management of decommissioning for safe and rational work to secure reduction of worker's exposure and prevent the spreading of contamination. (T. Tanaka)

Dispersion of radioactive materials from JRTR following a postulated accident using HOTSPOT code

International Nuclear Information System (INIS)

Mistarihi, Qusai M.; Lee, Kwan Hee

2013-01-01

Jordan Research and Training Reactor (JRTR) is the first nuclear facility in Jordan. The JRTR is 5 MW, light water moderated and open type pool reactor. In case of an accident, the radioactive materials will be released to the surrounding environment and endanger the people living in the vicinity of the reactor. However, up to now, no study has been published about the dispersion of radioactive materials from JRTR in case of an accident. As preliminary stage for the construction of the JRTR, the dispersion of the radioactive materials from JRTR in case of an accident was studied using HOTSOT code. The result of the report indicates that for ground level release with an average speed of 3.6 m/s of hourly averaged meteorological data for one year with a dominant direction from the west a person located at distance .062 km from the reactor site will receive .25 Sv

Dispersion of radioactive materials from JRTR following a postulated accident using HOTSPOT code

Energy Technology Data Exchange (ETDEWEB)

Mistarihi, Qusai M.; Lee, Kwan Hee [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

2013-10-15

Jordan Research and Training Reactor (JRTR) is the first nuclear facility in Jordan. The JRTR is 5 MW, light water moderated and open type pool reactor. In case of an accident, the radioactive materials will be released to the surrounding environment and endanger the people living in the vicinity of the reactor. However, up to now, no study has been published about the dispersion of radioactive materials from JRTR in case of an accident. As preliminary stage for the construction of the JRTR, the dispersion of the radioactive materials from JRTR in case of an accident was studied using HOTSOT code. The result of the report indicates that for ground level release with an average speed of 3.6 m/s of hourly averaged meteorological data for one year with a dominant direction from the west a person located at distance .062 km from the reactor site will receive .25 Sv.

Results of the IAEA CRP on studies of advanced reactor technology options for effective incineration of radioactive waste

International Nuclear Information System (INIS)

Maschek, W.; Stanculescu, A.; ); Gopalakrishnan, V.

2007-01-01

The IAEA has initiated a Coordinated Research Project (CRP) on 'Studies of Advanced Reactor Technology Options for Effective Incineration of Radioactive Waste'. The overall objective of the CRP, performed within the framework of IAEA's Nuclear Power Technology Development Section's Technical Working Group on Fast Reactors (TWG-FR), is to increase the capability of Member States in developing and applying advanced technologies in the area of long-lived radioactive waste utilization and transmutation. More specifically, the final goal of the CRP is to deepen the understanding of the dynamics of transmutation systems, especially systems with high minor actinide content. Currently, 20 institutions from 15 member states and one international organization are participating in this CRP. The current author list comprises the participants of the last CRP Vienna meeting. The CRP concentrates on the assessment of the transient behaviour of various transmutation systems. For a sound assessment of the transient and accident behaviour, neutron kinetics and dynamics methods and codes have to be qualified, especially as the margins for the safety relevant neutronics parameters are generally becoming small in a transmutation system. Hence, the availability of adequate and qualified methods for the analysis of the various systems is an important point of the exercise. A benchmarking effort between the codes and nuclear data used for the analyses has been performed, which will help specifying the range of validity of methods, and also formulate requirements for future theoretical and experimental research. Should transient experiments become available during the course of the CRP, experimental benchmarking work will also be pursued

Survey of legal aspects, regulations, standards and guidelines applicable to radioactive waste management of the Brazilian Multipurpose Reactor - RMB

International Nuclear Information System (INIS)

Salvetti, T.C.; Marumo, J.T.

2017-01-01

In Brazil, the Brazilian Nuclear Energy Commission (CNEN) and Brazilian Institute of Environment and Renewable Natural Resources (IBAMA) are the agencies responsible for the execution, regulation and control of nuclear and environmental policies, respectively. Such regulatory activities are very comprehensive (IBAMA) or too specific (CNEN), revealing other aspects that would, also, need to be observed so that the management could be carried out efficiently (quality) and effectively (safety), including the three governmental administrative levels: Federal, State and Municipal. In addition to laws, regulations, decrees and resolutions, there are also national and international standards and guides that provide guidelines for structuring the current management and the use of best regulatory practices. The Brazilian Multipurpose Reactor Enterprise (RMB) is a CNEN project, complying with a Multi-Year Plan of the Brazilian Ministry of Planning, Development and Management (MPDG). The Enterprise is being developed under the responsibility of the Directorate of Research and Development - DPD of CNEN and will have a facility for treatment and initial temporary storage of the radioactive waste generated by the operation of the research reactor and the activities carried out in the associated laboratories. The RMB will be built in the city of IPERÓ, located in the state of São Paulo, near ARAMAR Experimental Center of the Brazilian Navy. This work aims to present the research results regarding the various aspects that regulate, legislate and standardize the practices proposed to the Radioactive Waste Management of the RMB project. (author)

Survey of legal aspects, regulations, standards and guidelines applicable to radioactive waste management of the Brazilian Multipurpose Reactor - RMB

Energy Technology Data Exchange (ETDEWEB)

Salvetti, T.C.; Marumo, J.T., E-mail: salvetti@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

2017-07-01

In Brazil, the Brazilian Nuclear Energy Commission (CNEN) and Brazilian Institute of Environment and Renewable Natural Resources (IBAMA) are the agencies responsible for the execution, regulation and control of nuclear and environmental policies, respectively. Such regulatory activities are very comprehensive (IBAMA) or too specific (CNEN), revealing other aspects that would, also, need to be observed so that the management could be carried out efficiently (quality) and effectively (safety), including the three governmental administrative levels: Federal, State and Municipal. In addition to laws, regulations, decrees and resolutions, there are also national and international standards and guides that provide guidelines for structuring the current management and the use of best regulatory practices. The Brazilian Multipurpose Reactor Enterprise (RMB) is a CNEN project, complying with a Multi-Year Plan of the Brazilian Ministry of Planning, Development and Management (MPDG). The Enterprise is being developed under the responsibility of the Directorate of Research and Development - DPD of CNEN and will have a facility for treatment and initial temporary storage of the radioactive waste generated by the operation of the research reactor and the activities carried out in the associated laboratories. The RMB will be built in the city of IPERÓ, located in the state of São Paulo, near ARAMAR Experimental Center of the Brazilian Navy. This work aims to present the research results regarding the various aspects that regulate, legislate and standardize the practices proposed to the Radioactive Waste Management of the RMB project. (author)

Radioactive Waste Management and Nuclear Facility Decommissioning Progress in Iraq - 13216

Energy Technology Data Exchange (ETDEWEB)

Al-Musawi, Fouad; Shamsaldin, Emad S.; Jasim, Hadi [Ministry of Science and Technology (MoST), Al-Jadraya, P.O. Box 0765, Baghdad (Iraq); Cochran, John R. [Sandia National Laboratories1, New Mexico, Albuquerque New Mexico 87185 (United States)

2013-07-01

Management of Iraq's radioactive wastes and decommissioning of Iraq's former nuclear facilities are the responsibility of Iraq's Ministry of Science and Technology (MoST). The majority of Iraq's former nuclear facilities are in the Al-Tuwaitha Nuclear Research Center located a few kilometers from the edge of Baghdad. These facilities include bombed and partially destroyed research reactors, a fuel fabrication facility and radioisotope production facilities. Within these facilities are large numbers of silos, approximately 30 process or waste storage tanks and thousands of drums of uncharacterised radioactive waste. There are also former nuclear facilities/sites that are outside of Al-Tuwaitha and these include the former uranium processing and waste storage facility at Jesira, the dump site near Adaya, the former centrifuge facility at Rashdiya and the former enrichment plant at Tarmiya. In 2005, Iraq lacked the infrastructure needed to decommission its nuclear facilities and manage its radioactive wastes. The lack of infrastructure included: (1) the lack of an organization responsible for decommissioning and radioactive waste management, (2) the lack of a storage facility for radioactive wastes, (3) the lack of professionals with experience in decommissioning and modern waste management practices, (4) the lack of laws and regulations governing decommissioning or radioactive waste management, (5) ongoing security concerns, and (6) limited availability of electricity and internet. Since its creation eight years ago, the MoST has worked with the international community and developed an organizational structure, trained staff, and made great progress in managing radioactive wastes and decommissioning Iraq's former nuclear facilities. This progress has been made, despite the very difficult implementing conditions in Iraq. Within MoST, the Radioactive Waste Treatment and Management Directorate (RWTMD) is responsible for waste management and the

Radioactive Waste Management and Nuclear Facility Decommissioning Progress in Iraq - 13216

International Nuclear Information System (INIS)

Al-Musawi, Fouad; Shamsaldin, Emad S.; Jasim, Hadi; Cochran, John R.

2013-01-01

Management of Iraq's radioactive wastes and decommissioning of Iraq's former nuclear facilities are the responsibility of Iraq's Ministry of Science and Technology (MoST). The majority of Iraq's former nuclear facilities are in the Al-Tuwaitha Nuclear Research Center located a few kilometers from the edge of Baghdad. These facilities include bombed and partially destroyed research reactors, a fuel fabrication facility and radioisotope production facilities. Within these facilities are large numbers of silos, approximately 30 process or waste storage tanks and thousands of drums of uncharacterised radioactive waste. There are also former nuclear facilities/sites that are outside of Al-Tuwaitha and these include the former uranium processing and waste storage facility at Jesira, the dump site near Adaya, the former centrifuge facility at Rashdiya and the former enrichment plant at Tarmiya. In 2005, Iraq lacked the infrastructure needed to decommission its nuclear facilities and manage its radioactive wastes. The lack of infrastructure included: (1) the lack of an organization responsible for decommissioning and radioactive waste management, (2) the lack of a storage facility for radioactive wastes, (3) the lack of professionals with experience in decommissioning and modern waste management practices, (4) the lack of laws and regulations governing decommissioning or radioactive waste management, (5) ongoing security concerns, and (6) limited availability of electricity and internet. Since its creation eight years ago, the MoST has worked with the international community and developed an organizational structure, trained staff, and made great progress in managing radioactive wastes and decommissioning Iraq's former nuclear facilities. This progress has been made, despite the very difficult implementing conditions in Iraq. Within MoST, the Radioactive Waste Treatment and Management Directorate (RWTMD) is responsible for waste management and the Iraqi Decommissioning

Safe and secure: transportation of radioactive materials

International Nuclear Information System (INIS)

Howe, D.

2015-01-01

Western Waste Management Facility is Central Transportation Facility for Low and Intermediate waste materials. Transportation support for Stations: Reactor inspection tools and heavy water between stations and reactor components and single bundles of irradiated fuel to AECL-Chalk River for examination. Safety Track Record: 3.2 million kilometres safely travelled and no transportation accident - resulting in a radioactive release.

Radioactive waste management

International Nuclear Information System (INIS)

Alfredson, P.G.; Levins, D.M.

1975-08-01

Present and future methods of managing radioactive wastes in the nuclear industry are reviewed. In the stages from uranium mining to fuel fabrication, the main purpose of waste management is to limit and control dispersal into the environment of uranium and its decay products, particularly radium and radon. Nuclear reactors produce large amounts of radioactivity but release rates from commercial power reactors have been low and well within legal limits. The principal waste from reprocessing is a high activity liquid containing essentially all the fission products along with the transuranium elements. Most high activity wastes are currently stored as liquids in tanks but there is agreement that future wastes must be converted into solids. Processes to solidify wastes have been demonstrated in pilot plant facilities in the United States and Europe. After solidification, wastes may be stored for some time in man-made structures at or near the Earth's surface. The best method for ultimate disposal appears to be placing solid wastes in a suitable geological formation on land. (author)

Design and installation of a hot water layer system at the Tehran research reactor

Directory of Open Access Journals (Sweden)

Mirmohammadi Sayedeh Leila

2013-01-01

Full Text Available A hot water layer system (HWLS is a novel system for reducing radioactivity under research reactor containment. This system is particularly useful in pool-type research reactors or other light water reactors with an open pool surface. The main purpose of a HWLS is to provide more protection for operators and reactor personnel against undesired doses due to the radio- activity of the primary loop. This radioactivity originates mainly from the induced radioactivity contained within the cooling water or probable minute leaks of fuel elements. More importantly, the bothersome radioactivity is progressively proportional to reactor power and, thus, the HWLS is a partial solution for mitigating such problems when power upgrading is planned. Following a series of tests and checks for different parameters, a HWLS has been built and put into operation at the Tehran research reactor in 2009. It underwent a series of comprehensive tests for a period of 6 months. Within this time-frame, it was realized that the HWLS could provide a better protection for reactor personnel against prevailing radiation under containment. The system is especially suitable in cases of abnormality, e. g. the spread of fission products due to fuel failure, because it prevents the mixing of pollutants developed deep in the pool with the upper layer and thus mitigates widespread leakage of radioactivity.

Automatic radiometric analyzer for nuclides in nuclear reactor water

International Nuclear Information System (INIS)

Kitamura, Masao; Tokoi, Hiromi; Kitaguchi, Hiroshi; Ozawa, Yoshihiro; Urata, Megumu.

1981-01-01

Purpose: To shorten the processing time and improve the accuracy for processing water sampled from reactor coolants, as well as simplify the mechanism of the apparatus. Constitution: Reactor water sampled from reactor coolants, after filtered out with insoluble solids, is stored in an ion exchange container. Thereafter, the amount of ion exchanged water is regulated by the coarse measurement of radioactivity concentration by a monitor. Further, ion exchange resins are charged from a resin tank, agitated by gases and dispersed into sampled water. Then, all of the radioactive iodines contained in the sample are collected in the resins. The resins are recovered through evacuation into instrumenting vessels for measurement of radioactivity. Since ion exchange resins are dispersed in the sampled water in this system, the processing time can be shortened. (Ikeda, J.)

Radiation protection at the RA Reactor in 1993, RA research reactor, Part

International Nuclear Information System (INIS)

Ninkovic, M.; Pavlovic, R.; Mandic, M.; Sipka, V.; Grsic, Z.

1993-01-01

Radiation protection tasks which enable safe operation of the RA reactor, and are defined according the the legal regulations and IAEA safety recommendations are sorted into four categories in this report: (1) Control of the working environment, dosimetry and radiation protection at the RA reactor; (2) decontamination, collecting and treatment of fluid effluents and solid wastes; (3) Radioactivity control in the vicinity of the reactor and (4)meteorology measurements; (3). Each of the category is described as a separate annex of this report [sr

Human exposure to radiation following the release of radioactivity from a reactor accident: a quantitative assessment of the biological consequences

International Nuclear Information System (INIS)

Smith, H.; Stather, J.W.

1976-11-01

The objective of this review is to provide a biological basis upon which to assess the consequences of the exposure of a population to radioactivity released after a reactor accident. Depending upon the radiation dose, both early and late somatic damage could occur in the exposed population and hereditary effects may occur in their descendants. The development of dose-effect relationships has been based upon the limited amount of information available on humans, supplemented by data obtained from experiments on animals. (author)

Clearance of radioactive materials during reactor dismantling. Permanent enclosure instead of demolition and renaturation?; Freigabe radioaktiven Materials beim AKW-Abriss. Dauerhafter Einschluss statt Rueckbau?

Energy Technology Data Exchange (ETDEWEB)

NONE

2016-07-01

During reactor dismantling besides high-level radioactive wastes a large amount of low-level contaminated steel and concrete has to be disposed. In case that radioactivity falls below defined dose limits (10 micro Sv/person and year) these materials may be disposed in domestic waste landfill or in municipal incineration facilities. The issue is discussed in detail including the fact that many power plants are dismantled at the same time so that the contaminated materials might accumulate. Another issue is the occupational safety of contract workers during dismantling. The permanent enclosure could avoid this environmental contamination of decommissioned power plants might also be less expensive.

Canisters and nonfuel components at commercial nuclear reactors

International Nuclear Information System (INIS)

Gibbard, K.; Disbrow, J.

1994-01-01

This paper discusses detailed data on canisters and nonfuel components (NFC) at US commercial nuclear power reactors. A wide variety of NFC have been reported on the Form RW-859, open-quotes Nuclear Fuel Dataclose quotes survey. They may have been integral with an assembly, noncanistered in baskets, destined for disposal as low-level radioactive waste, or stored in canisters. Similarly, data on the family of canistered spent nuclear fuel (SNF) in storage pools was compiled. Approximately 85 percent of the 40,194 pieces of nonfuel assembly (NFA) hardware reported were integral with an assembly. This represents data submitted by 95 of the 107 reactors in 10 generic assembly classes. In addition, a total of 286 canisters have been reported as being in storage pools as of December 31, 1992. However, an additional 264 open baskets were also reported to contain miscellaneous SNF and nonfuel materials, garbage and debris. All of these 286 canisters meet the dimensional envelope requirements specified for disposal for open-quotes standard fuelclose quotes under the Standard Contract for Disposal of Spent Nuclear Fuel and/or High-Level Radioactive Waste (10 CFR 961); most of the baskets do not

Method of handling radioactive alkali metal waste

Science.gov (United States)

Wolson, R.D.; McPheeters, C.C.

Radioactive alkali metal is mixed with particulate silica in a rotary drum reactor in which the alkali metal is converted to the monoxide during rotation of the reactor to produce particulate silica coated with the alkali metal monoxide suitable as a feed material to make a glass for storing radioactive material. Silica particles, the majority of which pass through a 95 mesh screen or preferably through a 200 mesh screen, are employed in this process, and the preferred weight ratio of silica to alkali metal is 7 to 1 in order to produce a feed material for the final glass product having a silica to alkali metal monoxide ratio of about 5 to 1.

Method of handling radioactive alkali metal waste

International Nuclear Information System (INIS)

Mcpheeters, C.C.; Wolson, R.D.

1980-01-01

Radioactive alkali metal is mixed with particulate silica in a rotary drum reactor in which the alkali metal is converted to the monoxide during rotation of the reactor to produce particulate silica coated with the alkali metal monoxide suitable as a feed material to make a glass for storing radioactive material. Silica particles, the majority of which pass through a 95 mesh screen or preferably through a 200 mesh screen, are employed in this process, and the preferred weight ratio of silica to alkali metal is 7 to 1 in order to produce a feed material for the final glass product having a silica to alkali metal monoxide ratio of about 5 to 1

44 years of testing radioactive materials packages at ORNL

Energy Technology Data Exchange (ETDEWEB)

Shappert, L.B.; Ludwig, S.B. [Oak Ridge National Lab., Oak Ridge, TN (United States)

2004-07-01

This paper briefly reviews the package testing at the Oak Ridge National Laboratory (ORNL) since 1960 and then examines the trends in the testing activities that occurred during the same period. Radioactive material shipments have been made from ORNL since the 1940s. The first fully operating reactor built at the ORNL site was patterned after the graphite pile constructed by Enrico Fermi under Stagg Field in Chicago. After serving as a test bed for future reactors, it became useful as a producer of radioactive isotopes. The Isotopes Division was established at ORNL to furnish radioactive materials used in the medical community. Often these shipments have been transported by aircraft worldwide due to the short half-lives of many of the materials. This paper touches briefly on the lighter and smaller radioisotope packages that were being shipped from ORNL in large numbers and then deals with the testing of packages designed to handle large radioactive sources, such as spent fuel, and other fissile materials.

44 years of testing radioactive materials packages at ORNL

International Nuclear Information System (INIS)

Shappert, L.B.; Ludwig, S.B.

2004-01-01

This paper briefly reviews the package testing at the Oak Ridge National Laboratory (ORNL) since 1960 and then examines the trends in the testing activities that occurred during the same period. Radioactive material shipments have been made from ORNL since the 1940s. The first fully operating reactor built at the ORNL site was patterned after the graphite pile constructed by Enrico Fermi under Stagg Field in Chicago. After serving as a test bed for future reactors, it became useful as a producer of radioactive isotopes. The Isotopes Division was established at ORNL to furnish radioactive materials used in the medical community. Often these shipments have been transported by aircraft worldwide due to the short half-lives of many of the materials. This paper touches briefly on the lighter and smaller radioisotope packages that were being shipped from ORNL in large numbers and then deals with the testing of packages designed to handle large radioactive sources, such as spent fuel, and other fissile materials

Evolution in radioactive waste countermeasures

International Nuclear Information System (INIS)

Moriguchi, Yasutaka

1984-01-01

The establishment of radioactive waste management measures is important to proceed further with nuclear power development. While the storage facility projects by utilities are in progress, large quantity of low level wastes are expected to arise in the future due to the decommissioning of nuclear reactors, etc. An interim report made by the committee on radioactive waste countermeasures to the Atomic Energy Commission is described as follows: the land disposal measures of ultra-low level and low level radioactive wastes, that is, the concept of level partitioning, waste management, the possible practice of handling wastes, etc.; the treatment and disposal measures of high level radioactive wastes and transuranium wastes, including task sharing among respective research institutions, the solidification/storage and the geological formation disposal of high level wastes, etc. (Mori, K.)

A comparison of the radiological consequences of a HEU and LEU fueled research reactor

International Nuclear Information System (INIS)

Kollas, J.G.

1985-01-01

An analysis of the design basis accident radiological consequences of the HEU and LEU fueled Greek Research Reactor is presented. Doses and individual cancer risk from exposure to the passing radioactive cloud are estimated up to a distance of 20 km from the reactor site. Collective exposure and latent health effects are estimated for the total Athens area of 3081000 inhabitants. The results indicate that the plutonium isotopes buildup in the LEU fuel does not increase appreciably the consequences in respect to the HEU fueled reactor. The plutonium impact concerns mainly bone effects and secondly lung and whole body effects. The contribution to the limiting thyroid dose and the corresponding thyroid effects is insignificant. (author)

Immobilization of ion exchange radioactive resins of the TRIGA Mark III nuclear reactor; Inmovilizacion de resinas de intercambio ionico radiactivas del reactor nuclear Triga Mark III

Energy Technology Data Exchange (ETDEWEB)

Garcia M, H.; Emeterio H, M.; Canizal S, C. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, C.P. 11801 Mexico D.F. (Mexico)

2000-07-01

This work has the objective to develop the process and to define the agglutinating material which allows the immobilization of the ion exchange radioactive resins coming from the TRIGA Mark III nuclear reactor contaminated with Ba-133, Co-60, Cs-137, Eu-152, and Mn-54 through the behavior analysis of different immobilization agents such as: bitumens, cement and polyester resin. According to the International Standardization the archetype samples were observed with the following tests: determination of free liquid, leaching, charge resistance, biodegradation, irradiation, thermal cycle, burned resistance. Generally all the tests were satisfactorily achieved, for each agent. Therefore, the polyester resin could be considered as the main immobilizing. (Author)

Use of polymeric materials as the preservative agents for radioactive design components

International Nuclear Information System (INIS)

Sudareva, N.A.; Aleksandrov, V.O.; Zaviyalova, I.M.

1993-01-01

Among the problems concerned with decommissioning the nuclear plants (NP), the problems of the nuclear reactor operation hold a special place from the viewpoint of their radiation effects. One of the possible methods to prepare the radioactive wastes for subsequent disposal is the reactor isolation through filling up the cavities with the special solidifying material that provides its reliable leak-tightness. In this case the need for carrying out decontamination of the internal reactor cavities is eliminated. The more so, as the expensive and labour-intensive technology for dissolution and disposal of the surface radioactive deposits through decontamination is ineffective in this particular case and induced gamma-activity of the reactor equipment remains as usual. The technology of the NP isolation as a whole should provide maximum isolation of the internal cavities from the contact with environment due to corrosion damages and seal failure of the reactor equipment. In case of occurrence of the accident conditions with the reactor core failure and impossibility of its withdrawal the isolation should reliably provide the core subcriticality and protection of environment against radioactive contamination. The implementation of this method practically consists in the development of the preservative compounds having the required complex of the technological and technical characteristics. (authors). 2 figs., 1 tab

Environmental aspects of fusion reactors 1985

International Nuclear Information System (INIS)

Casini, G.; Ponti, C.; Rocco, P.

1986-01-01

The aspects of the environmental impact as expected from future fusion reactors are reviewed. The radioactive inventories consist in tritium and neutron-induced radioactivity in the structures. An analysis is performed of the radioactive releases from the different plant's systems in normal and accident conditions and typical emissions to the ambient are defined. Information is given on the waste management problems. Two appendixes give general information on tritium and safety guidelines

High-level radioactive waste in Canada. Background paper

International Nuclear Information System (INIS)

Fawcett, R.

1993-11-01

The disposal of radioactive waste is one of the most challenging environmental problems facing Canada today. Since the Second World War, when Canadian scientists first started to investigate nuclear reactions, there has been a steady accumulation of such waste. Research reactors built in the early postwar years produced small amounts of radioactive material but the volume grew steadily as the nuclear power reactors constructed during the 1960s and 1970s began to spawn used fuel bundles. Although this radioactive refuse has been safely stored for the short term, no permanent disposal system has yet been fully developed and implemented. Canada is not alone in this regard. A large number of countries use nuclear power reactors but none has yet put in place a method for the long-term disposal of the radioactive waste. Scientists and engineers throughout the world are investigating different possibilities; however, enormous difficulties remain. In Canada, used fuel bundles from nuclear reactors are defined as high-level waste; all other waste created at different stages in the nuclear fuel cycle is classified as low-level. Although disposal of low-level waste is an important issue, it is a more tractable problem than the disposal of high-level waste, on which this paper will concentrate. The paper discusses the nuclear fuel waste management program in Canada, where a long-term disposal plan has been under development by scientists and engineers over the past 15 years, but will not be completed for some time. Also discussed are responses to the program by parliamentary committees and aboriginal and environmental groups, and the work in the area being conducted in other countries. (author). 1 tab

High-level radioactive waste in Canada. Background paper

Energy Technology Data Exchange (ETDEWEB)

Fawcett, R [Library of Parliament, Ottawa, ON (Canada). Science and Technology Div.

1993-11-01

The disposal of radioactive waste is one of the most challenging environmental problems facing Canada today. Since the Second World War, when Canadian scientists first started to investigate nuclear reactions, there has been a steady accumulation of such waste. Research reactors built in the early postwar years produced small amounts of radioactive material but the volume grew steadily as the nuclear power reactors constructed during the 1960s and 1970s began to spawn used fuel bundles. Although this radioactive refuse has been safely stored for the short term, no permanent disposal system has yet been fully developed and implemented. Canada is not alone in this regard. A large number of countries use nuclear power reactors but none has yet put in place a method for the long-term disposal of the radioactive waste. Scientists and engineers throughout the world are investigating different possibilities; however, enormous difficulties remain. In Canada, used fuel bundles from nuclear reactors are defined as high-level waste; all other waste created at different stages in the nuclear fuel cycle is classified as low-level. Although disposal of low-level waste is an important issue, it is a more tractable problem than the disposal of high-level waste, on which this paper will concentrate. The paper discusses the nuclear fuel waste management program in Canada, where a long-term disposal plan has been under development by scientists and engineers over the past 15 years, but will not be completed for some time. Also discussed are responses to the program by parliamentary committees and aboriginal and environmental groups, and the work in the area being conducted in other countries. (author). 1 tab.

Characterization of the solid radioactive waste From Cernavoda NPP

International Nuclear Information System (INIS)

Iordache, M.; Laotaru, V.

2005-01-01

Full text: During the operation of a nuclear plant significant quantities of radioactive waste result that have a very large diversity. At Cernavoda NPP large amounts of wastes are either non-radioactive wastes or radioactive wastes, each of these being managed completely different from which other. For a CANDU type reactor, the appearance of radioactive wastes is due to contamination with the following types of radioactive substances: - fission products resulting from nuclear fuel burning; - activated products from materials composing the technological systems; - activated products in process fluids. Radioactive wastes can be in solid, liquid or gas form. At Cernavoda NPP the solid wastes represent about 70% of the waste volume which is produced during plant operation and as a consequence of maintenance and decontamination operations. The most important types of solid wastes that are obtained and then handled, processed (if necessary) and temporarily stored are: solid low-level radioactive wastes (classified as compactible and non-compactible), solid medium radioactive wastes, spent resins, used filters and filter cartridges. The liquid radioactive waste class includes organic liquids (used oil, scintillator liquids and used solvents) and aqueous wastes resulting from process system operating, from decontamination and maintenance operations. Radioactive gas wastes occur subsequently to the fission process inside the fuel elements as well as due to the neutron activation of process fluids in the reactor systems. As result of plant operation, iodine, noble gases, tritium and radioactive particles occur and are passed toward the ventilation stack in a controlled manner so that environmental release of radioactive materials with concentrations exceeding the maximum permissible level could not occur. (authors)

Activation product transport in fusion reactors

International Nuclear Information System (INIS)

Klein, A.C.

1983-01-01

Activated corrosion and neutron sputtering products will enter the coolant and/or tritium breeding material of fusion reactor power plants and experiments and cause personnel access problems. Radiation levels around plant components due to these products will cause difficulties with maintenance and repair operations throughout the plant. Similar problems are experienced around fission reactor systems. The determination of the transport of radioactive corrosion and neutron sputtering products through the system is achieved using the computer code RAPTOR. This code calculates the mass transfer of a number of activation products based on the corrosion and sputtering rates through the system, the deposition and release characteristics of various plant components, the neturon flux spectrum, as well as other plant parameters. RAPTOR assembles a system of first order linear differential equations into a matrix equation based upon the reactor system parameters. Included in the transfer matrix are the deposition and erosion coefficients, and the decay and activation data for the various plant nodes and radioactive isotopes. A source vector supplies the corrosion and neutron sputtering source rates. This matrix equation is then solved using a matrix operator technique to give the specific activity distribution of each radioactive species throughout the plant. Once the amount of mass transfer is determined, the photon transport due to the radioactive corrosion and sputtering product sources can be evaluated, and dose rates around the plant components of interest as a function of time can be determined. This method has been used to estimate the radiation hazards around a number of fusion reactor system designs

Coolant clean-up system in nuclear reactor

International Nuclear Information System (INIS)

Tsuburaya, Hirobumi; Akita, Minoru; Shiraishi, Tadashi; Kinoshita, Shoichiro; Okura, Minoru; Tsuji, Akio.

1987-01-01

Purpose: To ensure a sufficient urging pressure at the inlet of a coolant clean-up system pump in a nuclear reactor and eliminate radioactive contaminations to the pump. Constitution: Coolant clean-up system (CUW) pump in a nuclear reactor is disposed to the downstream of a filtration desalter and, for compensating the insufficiency of the urging pressure at the pump inlet, the reactor water intake port to the clean-up system is disposed to the downstream of the after-heat removing pump and the heat exchanger. By compensating the net positive suction head (NPSH) of the clean-up system from the residual heat removing system, the problems of insufficient NPSH for the CUW pump upon reactor shut-down can be dissolved and, accordingly, the reactor clean-up system can be arranged in the order of the heat exchanger, clean-up device and pump. Thus, the CUW pump acts on reactor water after cleaned-up in the clean-up device to reduce the radioactivity contamination to the pump. (Kawakami, Y.)

The Radioactive Waste Management at Studsvik

Energy Technology Data Exchange (ETDEWEB)

Hedlund, R; Lindskog, A

1966-04-15

The report was originally prepared as a contribution to the discussions in an IAEA panel on economics of radioactive waste management held in Vienna from 13 - 17 December 1965. It contains the answers and comments to the questions of a questionnaire for the panel concerning the various operations associated with the management (collection, transport, treatment, discharge, storage, and operational monitoring) of: - radioactive liquid wastes, except high-level effluents from reactor fuel recovering operations; - solid wastes, except those produced from treatment of high level wastes; - gaseous wastes produced from treatment of the foregoing liquid and solid wastes; - equipment decontamination facilities and radioactive laundries.

The Radioactive Waste Management at Studsvik

International Nuclear Information System (INIS)

Hedlund, R.; Lindskog, A.

1966-04-01

The report was originally prepared as a contribution to the discussions in an IAEA panel on economics of radioactive waste management held in Vienna from 13 - 17 December 1965. It contains the answers and comments to the questions of a questionnaire for the panel concerning the various operations associated with the management (collection, transport, treatment, discharge, storage, and operational monitoring) of: - radioactive liquid wastes, except high-level effluents from reactor fuel recovering operations; - solid wastes, except those produced from treatment of high level wastes; - gaseous wastes produced from treatment of the foregoing liquid and solid wastes; - equipment decontamination facilities and radioactive laundries

Method of processing radioactive liquid waste

International Nuclear Information System (INIS)

Motojima, Kenji; Kawamura, Fumio.

1981-01-01

Purpose: To increase the efficiency of removing radioactive cesium from radioactive liquid waste by employing zeolite affixed to metallic compound ferrocyanide as an adsorbent. Method: Regenerated liquid waste of a reactor condensation desalting unit, floor drain and so forth are collected through respective supply tubes to a liquid waste tank, and the liquid waste is fed by a pump to a column filled with zeolite containing a metallic compound ferrocyanide, such as with copper, zinc, manganese, iron, cobalt, nickel or the like. The liquid waste from which radioactive cesium is removed is dried and pelletized by volume reducing and solidifying means. (Yoshino, Y.)

Conceptual design of nuclear fusion power reactor DREAM. Reactor structures and remote maintenance

International Nuclear Information System (INIS)

Nishio, Satoshi; Seki, Yasushi; Ueda, Shuzo; Kurihara, Ryoichi; Adachi, Junichi; Yamazaki, Seiichiro; Hashimoto, Toshiyuki.

1997-01-01

Nuclear fusion reactors are required to be able to compete another energy sources in economy, reliability, safety and environmental integrity for commercial use. In the DREAM (DRastically EAsy Maintenance) reactor, a very low activated material of SiC/SiC composite has been introduced for the structural material, a reactor configuration for very easy maintenance and the helium gas of a high temperature for the cooling system, and hence DREAM has been proven to be very attractively as the commercial power reactor due to the high availability and efficiency of the plant and minimization of radioactive wastes. (author)

Radioactive contamination of the Dutch soil in consequence of the nuclear reactor accident at Chernobyl

International Nuclear Information System (INIS)

Koester, H.W.; Mattern, F.C.M.; Pennders, R.M.J.

1987-01-01

As a consequence of the reactor accident in Chernobyl air, contaminated with radioactive materials, spread over the Netherlands. From 2nd May to 6th May, with dry and to a greater extent with wet deposits, important quantities of radionuclides came upon the earth surface. In this period the weather circumstances within the Netherlands differed strongly resulting in distinct variations in deposit. In this document a preliminary picture is given of the contamination of the Dutch bottom on the basis of soil samplings made in the first few months after the accident. No attention is paid to geographic differences in bottom contamination. The contamination of the bottom is expressed in Bq/kg dry soil as well as in Bq/m 2 soil. 5 refs.; 6 tabs. (H.W.)

Hazardous chemical and radioactive wastes at Hanford

International Nuclear Information System (INIS)

Keller, J.F.; Stewart, T.L.

1991-07-01

The Hanford Site was established in 1944 to produce plutonium for defense. During the past four decades, a number of reactors, processing facilities, and waste management facilities have been built at Hanford for plutonium production. Generally, Hanford's 100 Area was dedicated to reactor operation; the 200 Area to fuel reprocessing, plutonium recovery, and waste management; and the 300 Area to fuel fabrication and research and development. Wastes generated from these operations included highly radioactive liquid wastes, which were discharged to single- and double-shell tanks; solid wastes, including both transuranic (TRU) and low-level wastes, which were buried or discharged to caissons; and waste water containing low- to intermediate-level radioactivity, which was discharged to the soil column via near-surface liquid disposal units such as cribs, ponds, and retention basins. Virtually all of the wastes contained hazardous chemical as well as radioactive constituents. This paper will focus on the hazardous chemical components of the radioactive mixed waste generated by plutonium production at Hanford. The processes, chemicals used, methods of disposition, fate in the environment, and actions being taken to clean up this legacy are described by location

Hazardous chemical and radioactive wastes at Hanford

International Nuclear Information System (INIS)

Keller, J.F.; Stewart, T.L.

1993-01-01

The Hanford Site was established in 1944 to produce plutonium for defense. During the past four decades, a number of reactors, processing facilities, and waste management facilities were built at Hanford for plutonium production. Generally, Hanford's 100 Area was dedicated to reactor operation; the 200 Areas to fuel reprocessing, plutonium recovery, and waste management; and the 300 Area to fuel fabrication and research and development. Wastes generated from these operations included highly radioactive liquid wastes, which were discharged to single- and double-shell tanks; solid wastes, including both transuranic and low-level wastes, which were buried or discharged to caissons; and waste water containing low- to intermediate-level radioactivity, which was discharged to the soil column via near-surface liquid disposal units such as cribs, ponds, and retention basins. Virtually all of the wastes contained hazardous chemicals as well as radioactive constituents. This paper focuses on the hazardous chemical components of the radioactive mixed waste generated by plutonium production at Hanford. The processes, chemicals used, methods of disposition, fate in the environment, and actions being taken to clean up this legacy are described by location

Deployment of Radioactive Waste Disposal Facility with the Introduction of Nuclear Power Plants in Kenya

Energy Technology Data Exchange (ETDEWEB)

Shadrack, Antoony; Kim, Changlak [KEPCO International Nuclear Graduate School, Uljin (Korea, Republic of)

2013-07-01

The nuclear power program will inevitably generate radioactive wastes including low-and intermediate radioactive waste and spent fuel. These wastes are hazardous to human health and the environment and therefore, a reliable radioactive waste disposal facility becomes a necessity. This paper describes Kenya's basic plans for the disposal of radioactive wastes expected from the nuclear program. This plan is important as an initial implementation of a national Low to intermediate level wastes storage facility in Kenya. In Kenya, radioactive waste is generated from the use of radioactive materials in medicine, industry, education and research and development. Future radioactive waste is expected to arise from nuclear reactors, oil exploration, radioisotope and fuel production, and research reactors as shown in table 1. The best strategy is to store the LILW and spent fuel temporarily within reactor sites pending construction of a centralized interim storage facility or final disposal facility. The best philosophy is to introduce both repository and nuclear power programs concurrently. Research and development on volume reduction technology and conceptual design of disposal facility of LILW should be pursued. Safe management of radioactive waste is a national responsibility for sustainable generation of nuclear power. The republic of Kenya is set to become the second African nuclear power generation country after South Africa.

Research and development activities for reactor decommissioning. Developing technology of Fuji Electric Co., Ltd

International Nuclear Information System (INIS)

Shirakawa, Masahiro; Takaya, Jyunichi; Mizukoshi, Seiji; Hosoda, Hiroshi; Tomizuka, Chiaki; Funaguchi, Susumu; Ito, Katsuhito

1997-01-01

Fuji Electric Co., Ltd. is conducting decommissioning R and D for commercial reactor, especially for gas cooled reactor since the construction of the Tokai-1 power station of JAPCO, in the field of system engineering, residual radioactivity evaluation, dismantling of core internals, remote handling, treatment and disposal of radioactive waste, and radioactivity measurement. These R and D have been performed mainly under contract of JAPCO and JAERI. This paper gives a summary of the present status and future plan concerning technical development for decommissioning of nuclear reactor by Fuji Electric Co., Ltd. (author)

Slow clean-up for fast reactor

Science.gov (United States)

Banks, Michael

2008-05-01

The year 2300 is so distant that one may be forgiven for thinking of it only in terms of science fiction. But this is the year that workers at the Dounreay power station in Northern Scotland - the UK's only centre for research into "fast" nuclear reactors - term as the "end point" by which time the site will be completely clear of radioactive material. More than 180 facilities - including the iconic dome that housed the Dounreay Fast Reactor (DFR) - were built at at the site since it opened in 1959, with almost 50 having been used to handle radioactive material.

The treatment of radioactive waste in Institute of Nuclear Physics of Uzbekistan

International Nuclear Information System (INIS)

Radyuk, R.I.

2001-01-01

Full text: The main purpose of radioactive waste treatment is security of humanity and environment for future. The formation of radioactive waste in Institute of Nuclear Physics connects with scientific and research works on reactor and cyclotron. There are works in the field of radiochemistry, activation analysis, research of material. It is connected with some different materials used in practical work: mountain rock, food-stuffs, biological materials and other. The Institute of Nuclear Physics has enterprise, making radioactive isotopes. In consequence of this work radioactive wastes form. Average annual volume of liquid radioactive waste is 2000 m 3 in year. During normal work of nuclear reactor and enterprise of radioactive isotope small part of radionuclides with gaseous waste gets in environment. The content of inert gas does not exceed 2% of permissible level . Value of radionuclides fall out in area from 0.5 Km to 10 Km does not differ global fall out and changes from 1.1.10 6 Bq/km 2 to 1.6.10 7 Bq/km 2 month (permissible doze - 5.6.10 8 Bq/km 2 .month). The solid radioactive waste of medium and low activity are burying on Republic point of radioactive waste storage. Annual volume of solid radioactive waste is 60 m 3 in year and total radioactivity is 10 11 Bk. The solid radioactive waste of high activity are going to of Chelyabinsk. The liquid radioactive waste belong to second and third group of radioactive waste (classification of IAEA). The decontamination of liquid radioactive waste are made on the station of liquid radioactive waste treatment by method of sedimentation and distillation. The productivity of this plant is 15m 3 in day. Before treatment liquid radioactive waste is analyzed to determine chemical and radiochemical composition. It is solution with content of salt from 0.8 g/l to 15 g/l, salt Ca 2+ and Mg 2+ - 20 mg-eqv/l, oxygen - 100 mg O 2 /l , activity from 10 2 Bq/l to 10 4 Bq/l. The radionuclides composition of liquid radioactive

Evaluation of radiation exposure from shoe-deodorants as radioactive consumer products

International Nuclear Information System (INIS)

Furuta, Etsuko; Yokota, Shigeaki; Aburai, Tamaru; Yoshizawa, Yukio

2007-01-01

Six shoe-deodorants on the market were analyzed using gamma-ray spectroscopy and radionuclide imaging techniques. The results reveal that at least three deodorants were 'radioactive consumer products' containing radionuclides of thorium (Th) series, uranium series, and potassium-40 that were added intentionally. Equivalent dose rates and effective dose rates were calculated using the activities in these deodorants. There were no samples breaking the nuclear reactor and fuel regulation law. Radioactive concentration of the deodorant for a shoe-shelf is higher than other deodorants, and the total concentrations of daughter nuclides of Th which are radioactive equilibrium with 224 Ra exceeded 90 Bq·g -1 . The effective dose rate at one meter from the shoe-shelf-deodorant is 8.6x10 -4 μSv·h -1 . Another type of shoe-deodorants is an insole that causes the surface dose of plantar skin. The equivalent dose was calculated as 1.9 μSv·h -1 at one millimeter from the insole. This study suggested that it needs to watch severely over the deodorants because many kinds of deodorants are used in home and some deodorants are radioactive consumer products. (author)

Low and intermediate level radioactive waste in Mexico

International Nuclear Information System (INIS)

Paredes, L.C.; Ortiz, J.R.; Sanchez, S.

2002-01-01

Currently, it is necessary to establish, in a few years, a definitive repository for low and intermediate level radioactive waste in order to satisfy the necessities of Mexico for the next 50 years. Consequently, it is required to estimate the volumes of the radioactive waste generated annually, the stored volumes to-date and their projection to medium-term. On this subject, the annual average production of low and intermediate level radioactive waste from the electricity production by means of nuclear power reactors is 250 m 3 /y which consist of humid and dry solid waste from the 2 units of the Laguna Verde Nuclear Power plant having a re-use efficiency of effluents of 95%. On the other hand, the applications in medicine, industry and research generate 20 m 3 /y of solid waste, 280 m 3 /y of liquid waste and approximately 10 m 3 /y from 300 spent sealed radioactive sources. The estimation of the total volume of these waste to the year 2035 is 17500 m 3 corresponding to the 46% of the volume generated by the operation and maintenance of the 2 units of the Laguna Verde Nuclear Power plant, 34% to the decommissioning of these 2 units at the end of their useful life and 20% to the waste generated by applications in medicine, industry and research. (author)

Radioactivity and foods

International Nuclear Information System (INIS)

Olszyna Marzys, A.E.

1991-01-01

The purpose of this article is to describe and contrast two relationships between radiation and food-on the one hand, beneficial preservation of food by controlled exposure to ionizing radiation; and, on the other, contamination of food by accidental incorporation of radioactive nuclides within the food itself. In food irradiation, electrons or electromagnetic radiation is used to destroy microorganisms and insects or prevent seed germination. The economic advantages and health benefits of sterilizing food in this manner are clear, and numerous studies have confirmed that under strictly controlled conditions no undesirable changes or induced radioactivity is produced in the irradiated food. An altogether different situation is presented by exposure of food animals and farming areas to radioactive materials, as occurred after the major Soviet nuclear reactor accident at Chernobyl. This article furnishes the basic information needed to understand the nature of food contamination associated with that event and describes the work of international organizations seeking to establish appropriate safe limits for levels of radioactivity in foods. 14 refs, 4 tabs

The management of radioactive wastes in Canada

International Nuclear Information System (INIS)

1979-01-01

Ten papers are presented, dealing with the management and environmental impact of radioactive wastes, environmental considerations related to uranium mining and milling, the management of uranium refining wastes, reactor waste management, proposals for the disposal of low- and intermediate-level wastes, disposal of nuclear fuel wastes, federal government policy on radioactive waste management, licensing requirements, environmental assessment, and internatioal cooperation in wast management. (LL)

Microbiological treatment of low level radioactive waste

International Nuclear Information System (INIS)

Ashley, N.V.; Pugh, S.Y.R.; Banks, C.J.; Humphreys, P.N.

1992-01-01

This report summarises the work of an experimental programme investigating the anaerobic digestion of low-level radioactive wastes. The project focused on the selection of the optimum bioreactor design to achieve 95% removal or stabilisation of the biodegradable portion of low-level radioactive wastes. Performance data was obtained for the bioreactors and process scale-up factors for the construction of a full-scale reactor were considered. (author)

Overview of the reactor safety study consequence model

International Nuclear Information System (INIS)

Wall, I.B.; Yaniv, S.S.; Blond, R.M.; McGrath, P.E.; Church, H.W.; Wayland, J.R.

1977-01-01

The Reactor Safety Study (WASH-1400) is a comprehensive assessment of the potential risk to the public from accidents in light water power reactors. The engineering analysis of the plants is described in detail in the Reactor Safety Study: it provides an estimate of the probability versus magnitude of the release of radioactive material. The consequence model, which is the subject of this paper, describes the progression of the postulated accident after the release of the radioactive material from the containment. A brief discussion of the manner in which the consequence calculations are performed is presented. The emphasis in the description is on the models and data that differ significantly from those previously used for these types of assessments. The results of the risk calculations for 100 light water power reactors are summarized

Projected legislation on radioactive waste management

International Nuclear Information System (INIS)

Wagner, H.

1992-01-01

Should be regulatory proposals contained in the draft of a law to change the legal regulations concerning nuclear power (as of September 1, 1992) be put into effect, this would mean an essential conceptual change concerning radioactive waste management. The contribution examines the essential changes and comes to the following conclusion: 1. At present there is a need for concretization of regulations concerning reactor decommissioning by means of amendments of laws, legal regulations and administrative regulations. The set of rules concerning nuclear technology must be adapted to the specific situation in which reactor decommissioning, reactor dismantling and confinement are involved. 2. No convincing reacons for privatizing the construction and operation of radwaste repositories exist. The advantages of such a change in course are not apparent. 3. Direct radwaste disposal should be legally defined in clear terms as an independent and cumulative process of waste disposal (in addition to and apart from radwaste repositing and re-processing). Hereby the utilization of radioactive waste products should continue to be given priority. (orig./HSCH) [de

The Assesment Of Radioactive Accident Management On The RSG-GAS

International Nuclear Information System (INIS)

Soejoedi, Agoes; Karmana, Endang

2000-01-01

In the operational reactor facilities include RSG-GAS, safety factor for radioactive accident very important to be prioritized. Till now the anticipate happening radioactive accident on the RSG-GAS threat only by the RSG-GAS Operation Manual. For increasing the working function need to create radioactive accident management by facility level. From studying result which source IAEA guidebook, can be composed the assessment accident management of radioactive the RSG-GAS.The sketching this accident management of radioactive to be hoped can helping P2TRR organization by handling radioactive accident if this moment happen on the RSG-GAS

Preliminary definition of the design of a nuclear reactor for research and radioisotope production using natural uranium and heavy water

International Nuclear Information System (INIS)

Llagostera Beltran, J.I.

1982-01-01

A study was conducted about the evolution of the Brazilian importations of radioisotopes, from the beginning of the 70's since they have been increasingly used in the Country. In view of the limited production capacity of radioactive isotopes now existing in Brazil, a nuclear reactor type (natural uranium and heavy water) was defined, for research and production of radioisotopes, wich, besides providing, at least partially, the Brazilian needs of said isotopes, permits a large national participation in its project, construction and operating maintenance. The processes for heavy water production have been analyzed and it could be detected what is the best alternative for the production thereof, in low scale, in Brazil. The options concerning the definition of the main components of the reactor were justified and its most important features were determined, in relation to the neutronic and thermal aspects, being so defined its most significant parameters. The annual quantities were estimated, in terms of total and specific activity, for the radioisotopes that could be obtained by means of the proposed reactor, which, by now, are participating, to a large extent, in the total of Brazilian importation of radioactive isotopes. (Author) [pt

Radioactive fallout from the Chernobyl nuclear reactor accident

International Nuclear Information System (INIS)

Beiriger, J.M.; Failor, R.A.; Marsh, K.V.; Shaw, G.E.

1987-08-01

This report describes the detection of fallout in the United States from the Chernobyl nuclear reactor accident. As part of its environmental surveillance program, Lawrence Livermore National Laboratory maintained detectors for gamma-emitting radionuclides. Following the reactor accident, additional air filters were set out. Several uncommon isotopes were detected at the time the plume passed into the US

Development of high-frequency induction melting system for radioactive solid wastes

International Nuclear Information System (INIS)

Kawaguchi, Ichiro; Yamazaki, Seichiro; Takahashi, Noriaki; Kugai, Katsutoshi; Yokozawa, Minoru

2004-01-01

Kawasaki Heavy Industries, Ltd. developed an active insulation (AI) method radiofrequency melting system as a new melting treatment system of radioactive solid wastes and proved production of waste satisfied the treatment performances and burying by repeating many practical melting tests. The melting vessel uses a low-priced ceramic canister with nonelectrical conductivity, which is able to treat wastes with large amount of inorganic substances. The wastes melted in the canister is taken out the canister itself from radiofrequency melting reactor and solidified after cooling. The cool canister is stored in 2001 metal drum filling up a gap with mortal for laying underground. New radiofrequency melting reactor, 1/3 scale melting test, estimation of scale effects, melting tests for practical use and the total system are explained. (S.Y.)

Chapter 8. The radioactivity sector

International Nuclear Information System (INIS)

Conti, Robert; Debetencourt, Michel; Cregut, Andre; Grauby, Andre; Sousselier, Yves

1980-01-01

The object of this work is to examine the interactions between the activities of the nuclear industry (generating, transmission and distribution) and the environment, whilst showing to what extent the facilities are likely to affect it adversely and describing the measures taken to lessen the detrimental effects. The chapter dealing with radioactivity among the 'nuisance sectors' includes the following headings: natural radioactivity and the biological effects of radiation, the operation of a power station (principle, generating steam from nuclear energy, different types of reactors, safety barriers), radioactive effluents and wastes, nuclear controls and the environment, measures taken in the event of an accident occurring in a nuclear power station, the dismantling and decommissioning of power stations [fr

Advanced robotic remote handling system for reactor dismantlement

International Nuclear Information System (INIS)

Shinohara, Yoshikuni; Usui, Hozumi; Fujii, Yoshio

1991-01-01

An advanced robotic remote handling system equipped with a multi-functional amphibious manipulator has been developed and used to dismantle a portion of radioactive reactor internals of an experimental boiling water reactor in the program of reactor decommissioning technology development carried out by the Japan Atomic Energy Research Institute. (author)

Transport of radioactive materials

International Nuclear Information System (INIS)

Lenail, B.

1984-01-01

Transport of radioactive materials is dependent of transport regulations. In practice integrated doses for personnel during transport are very low but are more important during loading or unloading a facility (reactor, plant, laboratory, ...). Risks occur also if packagings are used outside specifications. Recommendations to avoid these risks are given [fr

Generic impact statement for commercial radioactive waste management

International Nuclear Information System (INIS)

Unruh, C.M.

1976-01-01

ERDA is preparing a generic environmental impact statement on the treatment and disposal of waste resulting from commercial reactors and post fission operations in the light water reactor (LWR) fuel cycle. Expert contributions will be provided by many of the ERDA national laboratories and contractors. The waste management aspects of the statement will be based on available technology as presented in the recently issued ''Alternatives for Managing Waste from Reactors and Post Fission Operations in the LWR Fuel Cycle,'' ERDA-76-43 Document. This 1500 page, five volume Technical Alternative Document (TAD) describes the status of technology (to September, 1975) for handling post fission radioactive waste generated by the production of electricity by nuclear power light water reactor-generator systems. The statement will be generic in nature discussing typical or hypothetical facilities in typical or hypothetical environments. It is not intended to replace environmental statements required in support of specific projects nor for Nuclear Regulatory Commission licensing procedures. A major purpose of the generic statement is to inform the public and to solicit comments on the ERDA program for: (1) the final disposition of commercial radioactive waste, (2) waste treatment, (3) waste interim storage, and (4) transportation of waste. The statement will discuss the ERDA contingency program to provide retrievable storage of such waste if they should be transferred to Federal custody prior to the availability of the geologic isolation facilities for terminal disposal. The generic statement will not address radioactive waste resulting from U.S. Defense Programs, the mining or milling of uranium, the management of waste from the breeder reactor program, waste from other nations, nor will it include an evaluation of the impact of waste resulting from power sources other than light water reactors

76 FR 42074 - Consideration of Rulemaking To Address Prompt Remediation of Residual Radioactivity During...

Science.gov (United States)

2011-07-18

... Address Prompt Remediation of Residual Radioactivity During Operations AGENCY: Nuclear Regulatory... radioactivity during the operational phase of licensed material sites and nuclear reactors. The NRC has not... to the decommissioning planning process by addressing remediation of residual radioactivity during...

Waste Management During RA Reactor Decommissioning

International Nuclear Information System (INIS)

Markovic, M.; Avramovic, I.

2008-01-01

The objective of radioactive waste management during the RA reactor decommissioning is to deal with radioactive waste in a manner that protects human health and the environment now and in the future. The estimation of waste quantities to be expected during decommissioning is a very important step in the initial planning. (author)

Preliminary analysis of the induced structural radioactivity inventory of the base-case aqueous accelerator transmutation of waste reactor concept

International Nuclear Information System (INIS)

Bezdecny, J.A.; Vance, K.M.; Henderson, D.L.

1995-01-01

The purpose of the Los Alamos National Laboratory Accelerator Transmutation of (Nuclear) Waste (ATW) project is the substantial reduction in volume of long-lived high-level radioactive waste of the US in a safe and energy-efficient manner. An evaluation of the ATW concept has four aspects: material balance, energy balance, performance, and cost. An evaluation of the material balance compares the amount of long-lived high-level waste transmuted with the amount and type, of waste created in the process. One component of the material balance is the activation of structural materials over the lifetime of the transmutation reactor. A preliminary radioactivity and radioactive mass balance analysis has been performed on four structure regions of the reaction chamber: the tungsten target, the lead annulus, six tubing materials carrying the actinide slurry, and five reaction vessel structural materials. The amount of radioactive material remaining after a 100-yr cooling period for the base-case ATW was found to be 338 kg of radionuclides. The bulk of this material (313 kg) was generated in the zirconium-niobium (Zr-Nb) actinide tubing material. Replacement of the Zr-Nb tubing material with one of the alternative tubing materials analyzed would significantly reduce the short- and long-term radioactive mass produced. The alternative vessel material Al-6061 alloys, Tenelon, HT-9, and 2 1/4 Cr-1 Mo and the alternative actinide tubing materials Al-6061 alloy, carbon-carbon matrix, silicon carbide, and Ti-6 Al-4 V qualify for shallow land burial. Alternative disposal options for the base-case structural material Type 304L stainless steel and the actinide tubing material Zr-Nb will need to be considered as neither qualifies for shallow land burial

Analysis on Radioactive Waste Transmutation in Light Water cooled Hyb-WT

International Nuclear Information System (INIS)

Hong, Seonghee; Kim, Myung Hyun

2014-01-01

A feasibility of realization is much higher in FFHR compared with pure fusion. A combination of plasma fusion source for neutrons with a subcritical reactor at the blanket side has much higher capability in transmutation of waste as well as reactor safety compared with fission reactor options. Fusion-Fission Hybrid Reactor (FFHR) uses various coolants depending on the purpose. It is important that coolant being used should be suitable to reactor purpose, because reactor performance and the design constraints may change depending on the coolant. There are basically two major groups of coolants for FFHR. One group of coolant does not contain Li. They are Na, Pb-Bi, H 2 O and D 2 O. The other group contains Li for tritium breeding. They are Li, LiPb, LiSN, FLIBE and FLiNaBe. Currently, the issue in FFHR is its implication for radioactive waste transmutation (FFHR for WT). Because radioactive wastes of spent nuclear fuel (SNF) are transmuted using fusion neutron source. Therefore a suitable coolant should be used for effective waste transmutation. . In FFHR for WT, LiPb coolant is being used mainly because of tritium production in Li and high neutron economic through reaction in Pb. However different coolants use such as Na, Pb-Bi are used in fast reactors and accelerator driven systems (ADS) having same purpose. In this study, radioactive waste transmutation performance of various coolants mentioned above will be compared and analyzed. Through this study, the coolants are judged primarily for their support to waste transmutation disregarding their limitation to reactor design and tritium breeding capability. First, performance of the light water coolant regarding radioactive waste transmutation was analyzed among various coolants mentioned above. In this paper, performance of radioactive waste transmutation can be known depending on different volume fractions (54.53, 60.27, 97.94vol.%) of the light water. Light water dose required fusion power lower than LiPb due to

Radioactive Waste Management and Environmental Contamination Issues at the Chernobyl Site

International Nuclear Information System (INIS)

Napier, Bruce A.; Schmieman, Eric A.; Voitsekhovitch, Oleg V.

2007-01-01

The destruction of the Unit 4 reactor at the Chernobyl Nuclear Power Plant resulted in the generation of radioactive contamination and radioactive waste at the site and in the surrounding area (referred to as the Exclusion Zone). In the course of remediation activities, large volumes of radioactive waste were generated and placed in temporary near surface waste-storage and disposal facilities. Trench and landfill type facilities were created from 1986 to 1987 in the Chernobyl Exclusion Zone at distances 0.5 to 15 km from the NPP site. This large number of facilities was established without proper design documentation, engineered barriers, or hydrogeological investigations and they do not meet contemporary waste-safety requirements. Immediately following the accident, a Shelter was constructed over the destroyed reactor; in addition to uncertainties in stability at the time of its construction, structural elements of the Shelter have degraded as a result of corrosion. The main potential hazard of the Shelter is a possible collapse of its top structures and release of radioactive dust into the environment. A New Safe Confinement (NSC) with a 100-years service life is planned to be built as a cover over the existing Shelter as a longer-term solution. The construction of the NSC will enable the dismantlement of the current Shelter, removal of highly radioactive, fuel-containing materials from Unit 4, and eventual decommissioning of the damaged reactor. More radioactive waste will be generated during NSC construction, possible Shelter dismantling, removal of fuel containing materials, and decommissioning of Unit 4. The future development of the Exclusion Zone depends on the future strategy for converting Unit 4 into an ecologically safe system, i.e., the development of the NSC, the dismantlement of the current Shelter, removal of fuel containing material, and eventual decommissioning of the accident site. To date, a broadly accepted strategy for radioactive waste

Radioactive waste management and environmental contamination issues at the Chernobyl site.

Science.gov (United States)

Napier, B A; Schmieman, E A; Voitsekovitch, O

2007-11-01

The destruction of the Unit 4 reactor at the Chernobyl Nuclear Power Plant resulted in the generation of radioactive contamination and radioactive waste at the site and in the surrounding area (referred to as the Exclusion Zone). In the course of remediation activities, large volumes of radioactive waste were generated and placed in temporary near-surface waste storage and disposal facilities. Trench and landfill type facilities were created from 1986-1987 in the Chernobyl Exclusion Zone at distances 0.5-15 km from the nuclear power plant site. This large number of facilities was established without proper design documentation, engineered barriers, or hydrogeological investigations and they do not meet contemporary waste-safety requirements. Immediately following the accident, a Shelter was constructed over the destroyed reactor; in addition to uncertainties in stability at the time of its construction, structural elements of the Shelter have degraded as a result of corrosion. The main potential hazard of the Shelter is a possible collapse of its top structures and release of radioactive dust into the environment. A New Safe Confinement (NSC) with a 100 y service life is planned to be built as a cover over the existing Shelter as a longer-term solution. The construction of the NSC will enable the dismantlement of the current Shelter, removal of highly radioactive, fuel-containing materials from Unit 4, and eventual decommissioning of the damaged reactor. More radioactive waste will be generated during NSC construction, possible Shelter dismantling, removal of fuel-containing materials, and decommissioning of Unit 4. The future development of the Exclusion Zone depends on the future strategy for converting Unit 4 into an ecologically safe system, i.e., the development of the NSC, the dismantlement of the current Shelter, removal of fuel-containing material, and eventual decommissioning of the accident site. To date, a broadly accepted strategy for radioactive waste

PWR-GALE, Radioactive Gaseous Release and Liquid Release from PWR

International Nuclear Information System (INIS)

Chandrasekaran, T.; Lee, J.Y.; Willis, C.A.

1988-01-01

1 - Description of program or function: The PWR-GALE (Boiling Water Reactor Gaseous and Liquid Effluents) Code is a computerized mathematical model for calculating the release of radioactive material in gaseous and liquid effluents from pressurized water reactors (PWRs). The calculations are based on data generated from operating reactors, field tests, laboratory tests, and plant-specific design considerations incorporated to reduce the quantity of radioactive materials that may be released to the environment. 2 - Method of solution: GALE calculates expected releases based on 1) standardized coolant activities derived from ANS Standards 18.1 Working Group recommendations, 2) release and transport mechanisms that result in the appearance of radioactive material in liquid and gaseous waste streams, 3) plant-specific design features used to reduce the quantities of radioactive materials ultimately released to the environs, and 4) information received on the operation of nuclear power plants. 3 - Restrictions on the complexity of the problem: The liquid release portion of GALE uses subroutines taken from the ORIGEN (CCC-217) to calculate radionuclide buildup and decay during collection, processing, and storage of liquid radwaste. Memory requirements for this part of the program are determined by the large nuclear data base accessed by these subroutines

The radiation safety assessment of the heating loop of district heating reactors

International Nuclear Information System (INIS)

Liu Yuanzhong

1993-01-01

The district heating reactors are used to supply heating to the houses in cities. The concerned problems are whether the radioactive materials reach the heated houses through heating loop, and whether the safety of the dwellers can be ensured. In order to prevent radioactive materials getting into the heated houses, the district heating reactors have three loops, namely, primary loop, intermediate loop, and heating loop. In the paper, the measures of preventing radioactive materials getting into the heating loop are presented, and the possible sources of the radioactivity in the water of the intermediate loop and the heating loop are given. The regulatory aim limit of radioactive concentration in the water of the intermediate loop is put forward, which is 18.5 Bq/l. Assuming that specific radioactivity of the water of contaminated intermediate loop is up to 18.5 Bq/l, the maximum concentration of radionuclides in water of the heating loop is calculated for the normal operation and the accident of district heating reactor. The results show that the maximum possible concentration is 5.7 x 10 -3 Bq/l. The radiation safety assessment of the heating loop is made out. The conclusions are that the district heating reactors do not bring any harmful impact to the dwellers, and the safety of the dwellers can be safeguarded completely

Radioactive contamination mapping system detailed design report

International Nuclear Information System (INIS)

Bauer, R.G.; O'Callaghan, P.B.

1996-08-01

The Hanford Site's 100 Area production reactors released radioactively and chemically contaminated liquids into the soil column. The primary source of the contaminated liquids was reactor coolant and various waste waters released from planned liquid discharges, as well as pipelines, pipe junctions, and retention basins leaking into the disposal sites. Site remediation involves excavating the contaminated soils using conventional earthmoving techniques and equipment, treating as appropriate, transporting the soils, and disposing the soils at ERDF. To support remediation excavation, disposal, and documentation requirements, an automated radiological monitoring system was deemed necessary. The RCMS (Radioactive Contamination Mapping System) was designed to fulfill this need. This Detailed Design Report provides design information for the RCMS in accordance with Bechtel Hanford, Inc. Engineering Design Project Instructions

Chemistry and radioactivity: a century after Marie Curie

International Nuclear Information System (INIS)

Guillaumont, R.

2011-01-01

Coupling chemistry and radioactivity has led to radiochemistry, the part of chemistry dealing with the behaviour of radioactive materials. Many activities are of concern, as well in basic research as in the fields of health and energy. They call researches going from the study of the extremely diluted radioactive material (environment) until that of the most man-made radioactive material ever produced (spent nuclear fuel from reactors). When radiochemistry is not the mirror of the traditional chemistry, it uses in radioactive surroundings its own methods based on the measurement of the emitted rays. Radiochemistry will have in the next decades a major input to prepare the nuclear energy of the future. (author)

Airborne concentrations of radioactive materials in severe accidents

International Nuclear Information System (INIS)

Ross, D.F. Jr.; Denning, R.S.

1989-01-01

Radioactive materials would be released to the containment building of a commercial nuclear reactor during each of the stages of a severe accident. Results of analyses of two accident sequences are used to illustrate the magnitudes of these sources of radioactive materials, the resulting airborne mass concentrations, the characteristics of the airborne aerosols, the potential for vapor forms of radioactive materials, the effectiveness of engineered safety features in reducing airborne concentrations, and the release of radioactive materials to the environment. Ability to predict transport and deposition of radioactive materials is important to assessing the performance of containment safety features in severe accidents and in the development of accident management procedures to reduce the consequences of severe accidents

Total cross section measurement of radioactive isotopes with a thin beam neutron spectrometer

International Nuclear Information System (INIS)

Razbudej, V.F.; Vertebnyj, V.P.; Padun, G.S.; Muravitskij, A.V.

1975-01-01

The method for measuring the neutron total cross sections of radioactive isotopes by a time-of-flight spectrometer with a narrow (0.17 mm in diameter) beam of thermal neutrons is described. The distinguishing feature of this method is the use of capillary samples with a small amount of substance (0.05-1.0 mg). The energy range is 0.01-0.3 eV. The total cross sections of irradiated samples of sub(153)Eu and sub(151)Eu are measured. From them are obtained the cross sections of sub(152)Eu (Tsub(1/2)=12.4 g) and of sub(154)E (Tsub(1/2)=8.6 yr); they equal 11400+-1400 and 1530+-190 barn at E=0.0253 eV. The cross section of the sub(152)Eu absorption for the thermal spectrum (T=333 K) is determined by the activation method; it is 8900+-1200 barn

Radioactive waste control at the reprocessing facility in fiscal 1980

International Nuclear Information System (INIS)

1982-01-01

At the fuel reprocessing facility of the Power Reactor and Nuclear Fuel Development Corporation (PNC), the release of radioactive gaseous and liquid wastes are controlled so as not to exceed the specific levels. Concentrated low and high level liquid wastes, sludge, etc. are contained in storage tanks. Low and high level solid wastes are stored in appropriate containers. In fiscal 1980 (April to March), the release of gaseous and liquid wastes was below the specific levels (as in the previous years). Based on the report made by PNC in accordance with the law concerning the regulation of reactors, etc., the following data are presented in tables: the released quantity of radioactive gaseous and liquid wastes in fiscal 1980, the cumulative stored quantity of radioactive liquid wastes up to fiscal 1980; the cumulative stored quantity of radioactive solid wastes up to fiscal 1980 and the quantity of the same stored in fiscal 1980. (J.P.N.)

Assessment of Radioactivity Inventory - a key parameter in the clearance for recycling process

International Nuclear Information System (INIS)

Larsson, Arne; Lundgren, Klas

2014-01-01

Decommissioning studies for nuclear power reactors are to be performed in order to assess the decommissioning costs and the waste volumes, as well as to provide data for the licensing and construction of the LILW repositories. An important part of this work is to estimate the amount of radioactivity in the different types of decommissioning waste. Studsvik has performed these assessments for all Swedish NPPs as well as other nuclear facilities in Sweden using thorough on-site sampling and robust calculations developed by Studsvik's team of senior experts. Precision has been found to be relatively high close to the reactor cores, but then declines as distance from the core increases. The decommissioning waste from a LWR can be separated into different categories such as: - Material affected by the neutron flux from the reactor core, - Process systems, - Waste handling systems, - Contaminated structures. The determined specific activities for different systems (or part of systems) are combined with data on weights and contaminated surface areas in order to assess the total activity. A key issue in the assessments has been efforts to reduce the uncertainties. Combining the unique knowledge in assessment of radioactivity inventories, the large data bank the waste processing represents and the knowledge and records from the laboratories, the activity determination codes can be validated and the waste processing analysis supported with additional data. (authors)

IAEA news: • Newcomer countries face common challenges in nuclear infrastructure development. • Safety and licensing requirements for small modular reactors: IAEA hosts first workshop for regulators. • IAEA reaches milestone in disposal of radioactive sources

International Nuclear Information System (INIS)

Kollar, Lenka; Dyck, Elisabeth; Dixit, Aabha; Gaspar, Miklos; Gil, Laura

2016-01-01

• Newcomer countries face common challenges in nuclear infrastructure development: Countries embarking on a nuclear power programme need to make sure that the development of their legal, regulatory and support infrastructure keeps pace with the construction of the power plant itself. This is the only way to ensure that the programme proceeds in a safe, secure and sustainable way, concluded participants of a workshop on nuclear power infrastructure development hosted at the IAEA last February. • Safety and licensing requirements for small modular reactors: IAEA hosts first workshop for regulators: A new generation of advanced, prefab nuclear power reactors called small modular reactors (SMRs) could be licensed and hit the market as early as 2020, and the IAEA is helping regulators prepare for their debut. In a series of workshops that began earlier this year, the IAEA is working closely with regulators on approaches to safety and licensing ahead of potential SMR deployment worldwide. • IAEA reaches milestone in disposal of radioactive sources: Successful tests of a promising technology for moving and storing low level radioactive sealed sources are paving the way for a new disposal method for dealing with small volumes of radioactive waste around the world. The method, which involves placing and covering sealed sources in a narrow hole a few hundred metres deep, would allow countries to safely and securely take charge of their own disused radioactive sources. The proof of concept for the technology was tested in Croatia late last year — without the use of actual radioactive material.

Radioactive substance separation systems

International Nuclear Information System (INIS)

Sakai, Takuhiko.

1981-01-01

Purpose: To enable separation of fission products, radioactive corrosion products and the likes in primary coolants with no requirement for the replacement of separation system during plant service life, by providing protruded magnetic pole plates in a liquid metal flow channel to thereby form slopes magnetic fields. Constitution: A plurality of magnetic pole plates are disposed vertically in a comb-like arrangement so as not to contact with each other along the direction of flow in a rectangular primary coolant pipeway at the exit of the reactor core in an LMFBR type reactor. Large magnetic poles are provided to the upper and lower sides of the pipeway and coils are wound on the side opposed to the pipeway. When electrical current is supplied to the coils, the magnetic pole is magnetized intensely and thus the magnetic pole plates are also magnetized intensely and thus the magnetic pole plates are also magnetized intensely to form large gradient in the magnetic fields between the upper and lower magnetic plates, whereby ferromagnetic and ferrimagnetic fission products and radioactive corrosion products in the coolants are intensely adsorbed and not detached by the flow of the coolants. Accordingly, the fission products and the radioactive corrosion products can surely be removed with no requirement for the exchange of separation system during plant service life. (Horiuchi, T.)

Fast molten salt reactor-transmuter for closing nuclear fuel cycle on minor actinides

International Nuclear Information System (INIS)

Dudnikov, A. A.; Alekseev, P. N.; Subbotin, S. A.

2007-01-01

Creation fast critical molten salt reactor for burning-out minor actinides and separate long-living fission products in the closed nuclear fuel cycle is the most perspective and actual direction. The reactor on melts salts - molten salt homogeneous reactor with the circulating fuel, working as burner and transmuter long-living radioactive nuclides in closed nuclear fuel cycle, can serve as an effective ecological cordon from contamination of the nature long-living radiotoxic nuclides. High-flux fast critical molten-salt nuclear reactors in structure of the closed nuclear fuel cycle of the future nuclear power can effectively burning-out / transmute dangerous long-living radioactive nuclides, make radioisotopes, partially utilize plutonium and produce thermal and electric energy. Such reactor allows solving the problems constraining development of large-scale nuclear power, including fueling, minimization of radioactive waste and non-proliferation. Burning minor actinides in molten salt reactor is capable to facilitate work solid fuel power reactors in system NP with the closed nuclear fuel cycle and to reduce transient losses at processing and fabrications fuel pins. At substantiation MSR-transmuter/burner as solvents fuel nuclides for molten-salt reactors various salts were examined, for example: LiF - BeF2; NaF - LiF - BeF2; NaF-LiF ; NaF-ZrF4 ; LiF-NaF -KF; NaCl. RRC 'Kurchatov institute' together with other employees have developed the basic design reactor installations with molten salt reactor - burner long-living nuclides for fluoride fuel composition with the limited solubility minor actinides (MAF3 10 mol %) allows to develop in some times more effective molten salt reactor with fast neutron spectrum - burner/ transmuter of the long-living radioactive waste. In high-flux fast reactors on melts salts within a year it is possible to burn ∼300 kg minor actinides per 1 GW thermal power of reactor. The technical and economic estimation given power

Development of multi-functional telerobotic systems for reactor dismantlement

International Nuclear Information System (INIS)

Fujii, Yoshio; Usui, Hozumi; Shinohara, Yoshikuni

1992-01-01

This report summarizes technological features of advanced telerobotic systems for reactor dismantling application developed at the Japan Atomic Energy Research Institute. Taking into consideration the special environmental conditions in reactor dismantling, major effort was made to develop multifunctional telerobotic system of high reliability which can be used to perform various complex tasks in an unstructured environment and operated in an easy and flexible manner. The system development was carried out through constructing three systems in seccession; a light-duty and a heavy-duty system as a prototype system for engineering test in cold environment, and a demonstration system for practical on-site application to dismantling highly radioactive reactor internals of an experimental boiling water reactor JPDR (Japan Power Demonstration Reactor). Each system was equipped with one or two amphibious manipulators which can be operated in either a push-button manual, a bilateral master-slave, a teach-and-playback or a programmed control mode. Different scheme was adopted in each system at designing the manipulator, transporter and man-machine interface so as to compare their advantages and disadvantages. According to the JPDR decommissioning program, the demonstration system was successfully operated to dismantle a portion of the radioactive reactor internals of the JPDR, which used underwater plasma arc cutting method and proved the usefulness of the multi-functional telerobotic system for reducing the occupational hazards and enhancing the work efficiency in the course of dismantling highly radioactive reactor components. (author)

77 FR 58416 - Comparative Environmental Evaluation of Alternatives for Handling Low-Level Radioactive Waste...

Science.gov (United States)

2012-09-20

... for Handling Low-Level Radioactive Waste Spent Ion Exchange Resins From Commercial Nuclear Power... Radioactive Waste Spent Ion Exchange Resins from Commercial Nuclear Power Reactors. DATES: Please submit... Evaluation of Alternatives for Handling Low-Level Radioactive Waste Spent Ion Exchange Resins from Commercial...

The Chernobyl reactor accident. Pt. 1 and 2

International Nuclear Information System (INIS)

1986-06-01

The report first summarizes the available information on the various incidents of the whole accident scenario, and combines the information to present a first general outline and a basis for appraisal. The most significant incidents reported, namely power excursion, core meltdown, and fire, are discussed with a view to the reactor design and safety of reactors installed in the FRG. The main differences and advantages of German reactor designs are shown, as e.g.: Power excursions are mastered by inherent physical conditions; far better redundancy of engineered safety systems; enclosure of the complete reactor cooling system in a pressure-retaining steel containment; reactor buildings being made of reinforced concrete. The second part of the report deals with the radiological effects to be expected for our country. Data are given on the varying radiological exposure of the different regions. The fate and uptake of radioactivity in the human body are discussed. The conclusion drawn from the data presented is that the individual exposure due to the reactor accident will remain within the variations and limits of natural radioactivity and effects. (orig./HP) [de

Radioactive waste management in a fuel reprocessing facility in fiscal 1982

International Nuclear Information System (INIS)

1984-01-01

In the fuel reprocessing facility of the Power Reactor and Nuclear Fuel Development Corporation, radioactive gaseous and liquid waste are released not exceeding the respective permissible levels. Radioactive concentrated solutions are stored at the site. Radioactive solid waste are stored appropriately at the site. In fiscal 1982, the released quantities of radioactive gaseous and liquid waste were both below the permissible levels. The results of radioactive waste management in the fuel reprocessing facility in fiscal 1982 are given in the tables: the released quantities of radioactive gaseous and liquid waste, the produced quantities of radioactive solid waste, and the stored quantities of radioactive concentrated solutions and of radioactive solid waste as of the end of fiscal 1982. (Mori, K.)

Gamma emitting radionuclides of the Test Reactor Area leaching ponds

International Nuclear Information System (INIS)

Millard, J.B.; Whicker, F.W.; Markham, O.D.

1978-01-01

Radioactive leaching ponds adjacent to the Test Reactor Area (TRA) located on the Idaho National Engineering Laboratory (INEL) Site were investigated to determine the seasonal distribution and ecological behavior of gamma emitting radionuclides. The potential hazards to man and the environment were considered through the biological export of radioactive materials from the ponds. Both biotic and abiotic pond compartments were sampled. Fall and winter biomass estimates showed that benthic periphyton comprised 52%, macrophytes and littoral vegetation 35%, and seston 10% of the total for all biotic compartments. Concentrations and concentration factors (CFs) for fall and winter are presented for Cr-51, Co-60, Zr-95, I-131, Cs-137, Ba-140, and Ce-141. Concentrations and CFs ranged over seven orders of magnitude for the various nuclides and compartments. Seston and zooplankton had the highest concentrations followed by periphyton, sediment, macrophytes, littoral plants, willow, and filtered water. Arthropods had variable concentrations and CFs. Significant seasonal differences were observed for concentrations and CFs in seston, macrophytes, and littoral vegetation. A compartmental inventory of total gamma emitting activity accounted for 254 Ci (9.25 TBq) of the 731 Ci (24.8 TBq) estimated to remain in the ponds at the time of sampling. Filtered water and surface sediments contained 99% of the total radioactivity, while periphyton and seston had most of the remaining 1%. An estimate of the avian export rate of radioactivity from the TRA ponds showed that potentially harvestable mourning doves had the lowest rate with 0.02 μCi/y. External tissues of migratory waterfowl were found to contribute 90% of the total exported activity for all birds. The total avian export rate was estimated to be 1350 μCi/y during 1975