WorldWideScience

Sample records for tritium transport behaviour

  1. Tritium behaviour in higher plants

    International Nuclear Information System (INIS)

    Guenot, J.

    1984-05-01

    Vine grapes and potato seedlings have been exposed in situ to tritiated water vapor and 14 C labeled carbon dioxide. Leaves sampling was done during and after the exposition. Measurements allowed to distinguish the three forms of tritium in leaves, i.e. tissue free water tritium (TFWT) and organically bound tritium (OBT), in exchangeable position or not. The results lead to a description of the dynamical behaviour of tritium between these three compartments. It has been shown that 20% of organically bound hydrogen is readily exchangeable thus being in permanent isotopic equilibium with tissue free water. Moreover, the activity of nonexchangeable OBT appears to be strongly related to the organic 14 C, which shows that photosynthesis is responsible of tritium incorporation in organic nonexchangeable position, and occurs with a 20% discrimination in favor of protium. In contrast with the other two compartments, this fixation is almost irreversible, which is a fact of importance from a radiological point of view [fr

  2. Tritium transport around nuclear facilities

    International Nuclear Information System (INIS)

    Murphy, C.E. Jr.; Sweet, C.W.

    1981-01-01

    The transport and cycling of tritium around nuclear facilities is reviewed with special emphasis on studies at the Savannah River Laboratory, Aiken, South Carolina. These studies have shown that the rate of deposition from the atmosphere, the site of deposition, and the subsequent cycling are strongly influenced by the compound with which the tritium is associated. Tritiated hydrogen is largely deposited in the soil, while tritiated water is deposited in the greatest quantity in the vegetation. Tritiated hydrogen is converted in the soil to tritiated water that leaves the soil slowly, through drainage and transpiration. Tritiated water deposited directly to the vegetation leaves the vegetation more rapidly after exposure. Only a small part of the tritium entering the vegetation becomes bound in organic molecules. However, it appears tht the existence of soil organic compounds with tritium concentrations greater than the equilibrium concentration in the associated water can be explained by direct metabolism of tritiated hydrogen in vegetation

  3. Behaviour of tritium in the environment

    International Nuclear Information System (INIS)

    1979-01-01

    Full text: There is considerable interest in the behaviour of radionuclides of global character that may be released to the environment through the development of nuclear power. Tritium is of particular interest due to its direct incorporation into water and organic tissue. Although there has been a large decrease (more than ten times) in tritium concentration since the stopping of nuclear weapons tests in the atmosphere, the construction in the near future of many water reactors and in the far future of fusion reactors could increase the present levels. Progress has been made during recent years in the assessment of tritium distribution, in detection methods and in biological studies While several meetings have given scientists an opportunity to present papers on tritium, no specific symposium on this topic has been organized by the IAEA since 1961. Thus the purpose of the meeting was to review recent advances and to report on the practical aspects of tritium utilization and monitoring. The symposium was jointly organized with OECD/NEA, in co-operation with the US Department of Energy and the Lawrence Livermore Laboratory. Papers were presented on distribution of tritium, evaluation of future discharges, measurement of tritium, tritium in the aquatic environment, tritium in the terrestrial environment, tritium in man and monitoring of tritium Very interesting papers were given on distribution of tritium and participants got a good idea of the circulation of this radionuclide Some new data were provided on tritium pollution from luminous compounds and we learnt that the tritium release of the Swiss luminous compounds industry is of the same order of magnitude as the tritium release of Windscale. Projections indicate that, in the USA, the total quantity of tritium contained in discarded digital watches will be equal, approximately ten years in the future, to the release of nuclear power reactors Whereas nuclear reactor discharges are controlled there is no control

  4. Tritium transport analysis for CFETR WCSB blanket

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Pinghui, E-mail: phzhao@mail.ustc.edu.cn; Yang, Wanli; Li, Yuanjie; Ge, Zhihao; Nie, Xingchen; Gao, Zhongping

    2017-01-15

    Highlights: • A simplified tritium transport model for CFETR WCSB blanket was developed. • Tritium transport process in CFETR WCSB blanket was analyzed. • Sensitivity analyses of tritium transport parameters were carried out. - Abstract: Water Cooled Solid Breeder (WCSB) blanket was put forward as one of the breeding blanket candidate schemes for Chinese Fusion Engineering Test Reactor (CFETR). In this study, a simplified tritium transport model was developed. Based on the conceptual engineering design, neutronics and thermal-hydraulic analyses of CFETR WCSB blanket, tritium transport process was analyzed. The results show that high tritium concentration and inventory exist in primary water loop and total tritium losses exceed CFETR limits under current conditions. Conducted were sensitivity analyses of influential parameters, including tritium source, temperature, flow-rate capacity and surface condition. Tritium performance of WCSB blanket can be significantly improved under a smaller tritium impinging rate, a larger flow-rate capacity or a better surface condition. This work provides valuable reference for the enhancement of tritium transport behavior in CFETR WCSB blanket.

  5. Tritium behaviour in ceramic breeder blankets

    International Nuclear Information System (INIS)

    Miller, J.M.

    1989-01-01

    Tritium release from the candidate ceramic materials, Li 2 O, LiA10 2 , Li 2 SiO 3 , Li 4 SiO 4 and Li 2 ZrO 3 , is being investigated in many blanket programs. Factors that affect tritium release from the ceramic into the helium sweep gas stream include operating temperature, ceramic microstructure, tritium transport and solubility in the solid. A review is presented of the material properties studied and of the irradiation programs and the results are summarized. The ceramic breeder blanket concept is briefly reviewed

  6. Modeling tritium transport in the environment

    International Nuclear Information System (INIS)

    Murphy, C.E. Jr.

    1986-01-01

    A model of tritium transport in the environment near an atmospheric source of tritium is presented in the general context of modeling material cycling in ecosystems. The model was developed to test hypotheses about the process involved in tritium cycling. The temporal and spatial scales of the model were picked to allow comparison to environmental monitoring data collected in the vicinity of the Savannah River Plant. Initial simulations with the model showed good agreement with monitoring data, including atmospheric and vegetation tritium concentrations. The model can also simulate values of tritium in vegetation organic matter if the key parameter distributing the source of organic hydrogen is varied to fit the data. However, because of the lack of independent conformation of the distribution parameter, there is still uncertainty about the role of organic movement of tritium in the food chain, and its effect on the dose to man

  7. Kinetic behaviour of tritium water in the simulated paddy

    International Nuclear Information System (INIS)

    Wang Shouxiang; Chen Chuanqun; Zhang Yongxi; Sun Zhiming; Huang Dan; Hu Bingmin

    1993-02-01

    The dynamic process of movement and transportation for tritium water in the simulated paddy have been investigated. The results showed that after the paddy water was filled the tritium water not only was transferred to the components of the system but also was rapidly dissipated to the outside of the system. The states of tritium in the rice and soil were tritium of free water and bound tritium. The tritium concentration in the early paddy water and late paddy water was monotonously decreasing with the time increasing. The tritium concentration of free water in the overground part of early rice was increasing at begin, and reached to maximum at the 8th day, then went down. The tritium concentration in bound tritium was monotonously increasing, and at the 22th day it was higher than free water tritium. The tritium concentration in early rice root was lower than in the overground part. The tritium concentrations of free water tritium and bound tritium in the overground part and root of late rice were decreasing at the sampling period. The total tritium in the soil of early rice could reach the maximum value within one day and then it decreased, but in the soil of late rice it was monotonously decreasing with the time

  8. Tritium transport in lithium ceramics porous media

    International Nuclear Information System (INIS)

    Tam, S.W.; Ambrose, V.

    1991-01-01

    A random network model has been utilized to analyze the problem of tritium percolation through porous Li ceramic breeders. Local transport in each pore channel is described by a set of convection-diffusion-reaction equations. Long range transport is described by a matrix technique. The heterogeneous structure of the porous medium is accounted for via Monte Carlo methods. The model was then applied to an analysis of the relative contribution of diffusion and convective flow to tritium transport in porous lithium ceramics. 15 refs., 4 figs

  9. Doses due to tritium releases by NET - data base and relevant parameters on biological tritium behaviour

    International Nuclear Information System (INIS)

    Diabate, S.; Strack, S.

    1990-12-01

    This study gives an overview on the current knowledge about the behaviour of tritium in plants and in food chains in order to evaluate the ingestion pathway modelling of existing computer codes for dose estimations. The tritium uptake and retention by plants standing at the beginning of the food chains is described. The different chemical forms of tritium, which may be released into the atmosphere (HT, HTO and tritiated organics), and incorporation of tritium into organic material of plants are considered. Uptake and metabolism of tritiated compounds in animals and man are reviewed with particular respect to organically bound tritium and its significance for dose estimations. Some basic remarks on tritium toxicity are also included. Furthermore, a choice of computer codes for dose estimations due to chronic or accidental tritium releases has been compared with respect to the ingestion pathway. (orig.) [de

  10. Helium Bubbles Cavitation Phenomena in Pb-15.7Li and Potential Impact on Tritium Transport Behaviour in HCLL Breeding Channels

    Energy Technology Data Exchange (ETDEWEB)

    Sedano, L. A.

    2007-09-27

    COMPU task is devoted to develop a Process Flow Diagram (PFD) modelling tool for DEMO tritium cycle for HCLL and HCPB blanket lines for DEMO. At the actual stage of definition of HCLL blanket design line this global objective requires to progress specifically on the physical reliability of tritium transport assessments at blanket design level. A rough reliability assessment with the identify cation of physical phenomena determining permeation rates into the coolant was tentatively advanced in COMPU Task Deliverable 1. In HCLL design, the tritium diffusion in the alloy under the flow conditions and radiation effects in Pb15.7Li can be theoretically justifies ed as the rate limiting processes for tritium transfer into the coolant. This Deliverable 2 focuses on the analysis of a specific radiation effect: the potential role of helium bubbles in Pb15.7Li, the discussion of its implications on tritium assessment for HCLL design and consequently the analysis of its quantitative impact (as cycle input) on HCLL PFD tritium cycle design. Thus, the contents of this report investigate: (1) the rationality of the consideration on HCLL design of helium bubble cavitation phenomena in irradiated Pb15.7Li channels on the base of fundamental analysis (He solution states in Pb15.7Li) from empirical clues provided by Pb15.7Li irradiation tests, (2) a preliminary rough He-bubble cavitation design assessment and bases for a more precise FEM calculation for helium bubble cavitation phenomena in HCLL blanket channels, (3) the analysis of direct experimental data and numerical developments needed for a precise cavitation assessment and (4) a proposal of the lay-out and general specifications of an integral proof-of-principle Cavitation Experiment (Cevitex) of Helium in Pb15.7Li. (Author) 40 refs.

  11. Helium Bubbles Cavitation Phenomena in Pb-15.7Li and Potential Impact on Tritium Transport Behaviour in HCLL Breeding Channels

    International Nuclear Information System (INIS)

    Sedano, L. A.

    2007-01-01

    COMPU task is devoted to develop a Process Flow Diagram (PFD) modelling tool for DEMO tritium cycle for HCLL and HCPB blanket lines for DEMO. At the actual stage of definition of HCLL blanket design line this global objective requires to progress specifically on the physical reliability of tritium transport assessments at blanket design level. A rough reliability assessment with the identify cation of physical phenomena determining permeation rates into the coolant was tentatively advanced in COMPU Task Deliverable 1. In HCLL design, the tritium diffusion in the alloy under the flow conditions and radiation effects in Pb15.7Li can be theoretically justifies ed as the rate limiting processes for tritium transfer into the coolant. This Deliverable 2 focuses on the analysis of a specific radiation effect: the potential role of helium bubbles in Pb15.7Li, the discussion of its implications on tritium assessment for HCLL design and consequently the analysis of its quantitative impact (as cycle input) on HCLL PFD tritium cycle design. Thus, the contents of this report investigate: (1) the rationality of the consideration on HCLL design of helium bubble cavitation phenomena in irradiated Pb15.7Li channels on the base of fundamental analysis (He solution states in Pb15.7Li) from empirical clues provided by Pb15.7Li irradiation tests, (2) a preliminary rough He-bubble cavitation design assessment and bases for a more precise FEM calculation for helium bubble cavitation phenomena in HCLL blanket channels, (3) the analysis of direct experimental data and numerical developments needed for a precise cavitation assessment and (4) a proposal of the lay-out and general specifications of an integral proof-of-principle Cavitation Experiment (Cevitex) of Helium in Pb15.7Li. (Author) 40 refs

  12. Tritium adsorption/release behaviour of advanced EU breeder pebbles

    Science.gov (United States)

    Kolb, Matthias H. H.; Rolli, Rolf; Knitter, Regina

    2017-06-01

    The tritium loading of current grades of advanced ceramic breeder pebbles with three different lithium orthosilicate (LOS)/lithium metatitanate (LMT) compositions (20-30 mol% LMT in LOS) and pebbles of EU reference material, was performed in a consistent way. The temperature dependent release of the introduced tritium was subsequently investigated by temperature programmed desorption (TPD) experiments to gain insight into the desorption characteristics. The obtained TPD data was decomposed into individual release mechanisms according to well-established desorption kinetics. The analysis showed that the pebble composition of the tested samples does not severely change the release behaviour. Yet, an increased content of lithium metatitanate leads to additional desorption peaks at medium temperatures. The majority of tritium is released by high temperature release mechanisms of chemisorbed tritium, while the release of physisorbed tritium is marginal in comparison. The results allow valuable projections for the tritium release behaviour in a fusion blanket.

  13. Tritium transport and control in the FED

    International Nuclear Information System (INIS)

    Rogers, M.L.

    1981-01-01

    The tritium systems for the FED have three primary purposes. The first is to provide tritium and deuterium fuel for the reactor. This fuel can be new tritium or deuterium delivered to the plant site, or recycled DT from the reactor that must be processed before it can be recycled. The second purpose of the FED tritium systems is to provide state-of-the-art tritium handling to limit worker radiation exposure and to minimize tritium losses to the environment. The final major objective of the FED tritium systems is to provide an integrated system test of the tritium handling technology necessary to support the fusion reactor program. Every effort is being made to incorporate available information from the Tritium System Test Assembly (TSTA) at Los Alamos National Laboratory, the Tokamak Fusion Test Reactor (TFTR) tritium systems, and the tritium handling information generated within DOE for the past 20 years

  14. Tritium

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    The role played the large amount supply of tritium and its effects are broadly reviewed. This report is divided into four parts. The introductory part includes the history of tritium research. The second part deals with the physicochemical properties of tritium and the compounds containing tritium such as tritium water and labeled compounds, and with the isotope effects and self radiation effects of tritium. The third part deals with the tritium production by artificial reaction. Attention is directed to the future productivity of tritium from B, Be, N, C, O, etc. by using the beams of high energy protons or neutrons. The problems of the accepting market and the accuracy of estimating manufacturing cost are discussed. The expansion of production may bring upon the reduction of cost but also a large possibility of social impact. The irradiation problem and handling problem in view of environmental preservation are discussed. The fourth part deals with the use of tritium as a target, as a source of radiation or light, and its utilization for geochemistry. The future development of the solid tritium target capable of elongating the life of neutron sources is expected. The rust thickness of the surface of iron can be measured with the X-ray of Ti-T or Zr-T. The tritium can substitute self-light emission paint or lamp. The tritium is suitable for tracing the movement of sea water and land surface water because of its long half life. (Iwakiri, K.)

  15. Tritium

    International Nuclear Information System (INIS)

    Fiege, A.

    1992-07-01

    This report contains information on chemical and physical properties, occurence, production, use, technology, release, radioecology, radiobiology, dose estimates, radioprotection and legal aspects of tritium. The objective of this report is to provide a reliable data base for the public discussion on tritium, especially with regard to its use in future nuclear fusion plants and its radiological assessment. (orig.) [de

  16. Shipment and Storage Containers for Tritium Production Transportation Casks

    International Nuclear Information System (INIS)

    Massey, W.M.

    1998-04-01

    The need for a shipping and storage container for the Tritium production transportation casks is addressed in this report. It is concluded that a shipping and storage container is not required. A recommendation is made to eliminate the requirement for this container because structural support and inerting requirements can be satisfied completely by the cask with a removable basket

  17. Impurity and trace tritium transport in tokamak edge turbulence

    DEFF Research Database (Denmark)

    Naulin, V.

    2005-01-01

    The turbulent transport of impurity or minority species, as for example tritium, is investigated in drift-Alfven edge turbulence. The full effects of perpendicular and parallel convection are kept for the impurity species. The impurity density develops a granular structure with steep gradients...

  18. Tritium

    Science.gov (United States)

    2011-11-01

    QUESTIONS 5 4 CONSTRAINTS OF BASIC PHYSICS 7 4.1 Neutronics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 4.2 Tritium Burnup Fraction...Requirements for tritium-breeding should be one of the key tradeoffs 5 in reactor design. For example, maximizing the burnup fraction fb (a plasma-physics...account for the heterogeneous geometry and structural materials of the reactor, it should be possible to calculate values of the TBR that will be

  19. Isotopic scaling of transport in deuterium-tritium plasmas

    International Nuclear Information System (INIS)

    Scott, S.D.; Murakami, M.; Adler, H.; Chang, Z.; Duong, H.; Grisham, L.R.; Fredrickson, E.D.; Grek, B.; Hawryluk, R.J.; Hill, K.W.; Hosea, J.; Jassby, D.L.; Johnson, D.W.; Johnson, L.C.; Loughlin, M.J.; Mansfield, D.K.; McGuire, K.M.; Meade, D.M.; Mikkelsen, D.M.; Murphy, J.; Park, H.K.; Ramsey, A.T.; Schivell, J.; Skinner, C.H.; Strachan, J.D.; Synakowski, E.J.; Taylor, G.; Thompson, M.E.; Wieland, R.; Zarnstorff, M.C.

    1995-01-01

    Both global and thermal energy confinement improve in high-temperature supershot plasmas in the Tokamak Fusion Test Reactor (TFTR) when deuterium beam heating is partially or wholly replaced by tritium beam heating. For the same heating power, the tritium-rich plasmas obtain up to 22% higher total energy, 30% higher thermal ion energy, and 20-25% higher central ion temperature. Kinetic analysis of the temperature and density profiles indicates a favorable isotopic scaling of ion heat transport and electron particle transport, with τ Ei (a/2) ∝ left angle A right angle 0.7-0.8 and τ pe (a) ∝ left angle A right angle 0.8 . (orig.)

  20. Stainless steel electrochemical behaviour - application to the decontamination of steel parts contaminated by tritium

    International Nuclear Information System (INIS)

    Bellanger, G.

    1991-01-01

    This purpose of this work is the study of an electrochemical decontamination process of stainless steel in which tritium is present on the surface of the metal, in the oxide layer and in the metal. We have first investigated the behaviour of the oxide layer. Then we have studied the hydrogen evolution, its diffusion and retrodiffusion in the metal. The results are applied to the decontamination of steel parts contamined by tritium. Part of the tritium can be eliminated by reducing the oxyde layer, which contains large amounts of tritium. However, it is more beneficial to electrolyse at the potential at which the H + ions are reduced. The hydrogen on the steel surface enters in the metal and displaces most of tritium located in the metallic layers near the surface. The tritium surface elimination rate is about 95%. The tritium eliminated through electrolysis is only a small fraction of all the tritium contained in the metal. However, according to conservation experiments of parts after electrolysis, it can be concluded that hydrogen, probably more strongly bound than tritium to steel, forms near the surface a barrier that prevents tritium retrodiffusion. Electrolysis appears as a satisfactory process for the surface decontamination of slightly tritiated steel parts. A decontamination automaton based on the preceding results is described using a pad electrolyser. This type of decontamination is little polluting, and the parts can be recycled after the in situ treatment [fr

  1. A novel method for trace tritium transport studies

    Czech Academy of Sciences Publication Activity Database

    Bonheure, G.; Mlynář, Jan; Murari, A.; Giroud, C.; Belo, P.; Bertalot, L.; Popovichev, S.; JET EFDA, Contributors.

    2009-01-01

    Roč. 49, č. 8 (2009), 085025 ISSN 0029-5515 R&D Projects: GA MŠk LA08048 Institutional research plan: CEZ:AV0Z20430508 Keywords : Tokamak * transport * tritium * tomography Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 4.270, year: 2009 http://www.iop.org/EJ/article/0029-5515/49/8/085025/nf9_8_085025.pdf

  2. Analysis of tritium behaviour and recovery from a water-cooled Pb17Li blanket

    International Nuclear Information System (INIS)

    Malara, C.; Casini, G.; Viola, A.

    1995-01-01

    The question of the tritium recovery in water-cooled Pb17Li blankets has been under investigation for several years at JRC Ispra. The method which has been more extensively analysed is that of slowly circulating the breeder out from the blanket units and of extracting the tritium from it outside the plasma vacuum vessel by helium gas purging or vacuum degassing in a suited process apparatus. A computerized model of the tritium behaviour in the blanket units and in the extraction system was developed. It includes four submodels: (1) tritium permeation process from the breeder to the cooling water as a function of the local operative conditions (tritium concentration in Pb17Li, breeder temperature and flow rate); (2) tritium mass balance in each breeding unit; (3) tritium desorption from the breeder material to the gas phase of the extraction system; (4) tritium extraction efficiency as a function of the design parameters of the recovery apparatus. In the present paper, on the basis of this model, a parametric study of the tritium permeation rate in the cooling water and of the tritium inventory in the blanket is carried out. Results are reported and discussed in terms of dimensionless groups which describe the relative effects of the overall resistance on tritium transfer to the cooling water (with and without permeation barriers), circulating Pb17Li flow rate and extraction efficiency of the tritium recovery unit. The parametric study is extended to the recovery unit in the case of tritium extraction by helium purge or vacuum degassing in a droplet spray unit. (orig.)

  3. Tritium transport and release from lithium ceramic breeder materials

    International Nuclear Information System (INIS)

    Johnson, C.E.; Kopasz, J.P.; Tam, S.W.

    1994-01-01

    In an operating fusion reactor,, the tritium breeding blanket will reach a condition in which the tritium release rate equals the production rate. The tritium release rate must be fast enough that the tritium inventory in the blanket does not become excessive. Slow tritium release will result in a large tritium inventory, which is unacceptable from both economic and safety viewpoints As a consequence, considerable effort has been devoted to understanding the tritium release mechanism from ceramic breeders and beryllium neutron multipliers through theoretical, laboratory, and in-reactor studies. This information is being applied to the development of models for predicting tritium release for various blanket operating conditions

  4. Some issues in two-dimensional modeling of tritium transport

    International Nuclear Information System (INIS)

    Tam, S.W.

    1991-01-01

    Among the major processes leading to tritium transport through Li ceramic breeders the percolation of gaseous tritium species through the connected porosity remains the lest amenable to a satisfactory treatment. The combination of diffusion and reaction through the convoluted transport pathways prescribed by the system of pores poses a formidable challenge. The key issue is to make the fundamental connection between the tortuousity of the medium with the transport processes in terms of only basic parameters that are amenable to fundamental understanding and experimental determinations. This fundamental challenges is met within the following approaches. The technique that we have employed is a random network percolation model. Local transport in each individual pore channel is described by a set of convection-diffusion-reaction equations. Long range transport is described by a matrix technique. The heterogeneous structure of the medium is accounted for via Monte Carlo methods. In this way the approach requires as inputs only physical-chemical parameters that are amenable to clear basic understanding and experimental determination. In the sense it provides predictive capability. The approach has been applied to an analysis of the concept of tritium residence time which is associated with the first passage time, a direct output of our analysis. In the next stage of our work the tool that we have developed would be employed to investigate the issues of vary large networks, realistic microstructural information and the effect of varying pressure gradient along the purge channels. We have demonstrated that the approach that has been adopted can be utilized to analyze in a very illuminating way the underlying issues of the concept of residence time. We believe that the present approach is ideally suited to tackle these very important yet difficult issues

  5. Transport of deuterium, tritium and helium in a tokamak

    International Nuclear Information System (INIS)

    Potters, J.H.H.M.

    1984-02-01

    A one-dimensional numerical model for determining steady-state radial profiles of the densities of the particles, including neutrals, in a multispecies toroidal plasma is described. For prescribed temperature profiles, the coupled momentum and particle balances of the ions are solved numerically with a newly developed compact finite difference scheme for a non-equidistant mesh. Neutral densities are obtained by solving the Boltzmann equations, using a collocation method. The model is applied to deuterium-tritium plasmas without and with a helium admixture. For the charged particles, Pfirsch-Schlueter transport, including the highly collisional extension, and either of two anomalous transport models are adopted. For equal densities of deuterons and tritons in the plasma centre, the neutral tritium density in front of the wall is found to be 1.3 to 1.6 times higher than that of deuterium, depending on the plasma density, the temperature profile and the transport model. Secondly, it is found that pumping neutral helium, originating from fusion alpha particles, out of a cold plasma/gas blanket surrounding the hot plasma is not feasible, as the helium gas density, corresponding to a relative abundance of alpha-particles in the plasma core below 10%, is very low. Although depending strongly on the ion transport model and being increased by elastic collisions between neutral helium and charged hydrogen isotopes, the neutral helium enrichment ratio is always much less than unity. (Auth.)

  6. Development of Tritium Permeation Analysis Code and Tritium Transport in a High Temperature Gas-Cooled Reactor Coupled with Hydrogen Production System

    Energy Technology Data Exchange (ETDEWEB)

    Chang H. Oh; Eung S. Kim; Mike Patterson

    2010-06-01

    Abstract – A tritium permeation analyses code (TPAC) was developed by Idaho National Laboratory for the purpose of analyzing tritium distributions in very high temperature reactor (VHTR) systems, including integrated hydrogen production systems. A MATLAB SIMULINK software package was used in developing the code. The TPAC is based on the mass balance equations of tritium-containing species and various forms of hydrogen coupled with a variety of tritium sources, sinks, and permeation models. In the TPAC, ternary fission and neutron reactions with 6Li, 7Li 10B, and 3He were taken into considerations as tritium sources. Purification and leakage models were implemented as main tritium sinks. Permeation of tritium and H2 through pipes, vessels, and heat exchangers were considered as main tritium transport paths. In addition, electroyzer and isotope exchange models were developed for analyzing hydrogen production systems, including high temperature electrolysis and sulfur-iodine processes.

  7. Source function for tritium transport models in the Pacific

    International Nuclear Information System (INIS)

    Fine, R.A.; Ostlund, H.G.

    1977-01-01

    An empirically fitted function describes surface Pacific Ocean tritium concentrations as varying exponentially with latitude, the r.m.s. fit to observations is 18%. The oceanic tritium concentration maximum in the North Pacific, which resulted from nuclear weapons testing, lagged the rain data by two to three years occurring in 1965--66. Tritium-salinity correlations are consistent with climatology. Tritium-longitude correlations are consistent with surface water circulation

  8. Tritium transport, influx, and helium ash measurements on TFTR during DT operation

    Science.gov (United States)

    Efthimion, P. C.; Johnson, L. C.; Skinner, C. H.

    1994-08-01

    The evolution of the tritium density profile is inferred from 14.1 MeV t(d,n)alpha and 2.5 MeV d(d,n)He-3 neutron emissivity profiles measured in a deuterium neutral beam heated plasma into which a small amount of tritium gas has been puffed. For the first time, hydrogenic ion transport coefficients in the form of a diffusivity and convective velocity are determined. The particle diffusivities of tritium and He-4 and the deuterium thermal diffusivity are of similar magnitudes, and thus are consistent with theoretically calculated ExB drift transport. The first measurements of helium ash have been made using charge exchange recombination spectroscopy (CHERS). The measured radial ash profile shape is consistent with that predicted from simulations that include calculations of the central alpha ash source and thermal ash transport. This suggests that ash transport in the plasma core will not be a fundamental limiting factor in determining helium exhaust rates in a reactor. The authors also report the first spectroscopic measurements of tritium Balmer-alpha emission which provided a measure of tritium influx from the limiter. Tritium influx persists in discharges subsequent to tritium neutral beam injection, decaying with an initial decay of 7.5 discharges, and followed by a long term decay on the order of 400 discharges. Tritium transport, influx, and helium ash transport are important issues concerning profile control, retention, and ash removal for future reactors, like ITER.

  9. Tritium from bombs - the time behaviour since 1963 in mean-European rivers and smaller hydrological systems

    International Nuclear Information System (INIS)

    Esser, N.

    1980-01-01

    Numerical simulation models are presented to describe the observed of nuclear bomb tritium fallout (lyrimeter measurements) in the unsaturated ground zone and the ground water. These models are based on the well-known time-dependence of the tritium concentration in the local rainy waters and on water balance parameters. The tritium migration behaviour can be described well by the drainage model, the leakage model and the flow model (program-out, measured data). (DG) [de

  10. Optimizing tritium extraction from a Permeator Against Vacuum (PAV) by dimensional design using different tritium transport modeling tools

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, P., E-mail: pablomiguel.martinez@ciemat.es [CIEMAT-LNF (Laboratorio Nacional de Fusion), Madrid (Spain); Moreno, C. [CIEMAT-LNF (Laboratorio Nacional de Fusion), Madrid (Spain); Martinez, I. [SENER Ingenieria y Sistemas, Provenca 392, 4a 08025 Barcelona (Spain); Sedano, L. [CIEMAT-LNF (Laboratorio Nacional de Fusion), Madrid (Spain)

    2012-08-15

    The Permeator Against Vacuum (PAV) has been conceived as the simplest, cost effective and reliable technology system dedicated to tritium extraction from breeding liquid metals. An optimal design of a PAV requires a detailed hydraulic design optimization for established operational ranges (HCLL at low velocities of {approx}1 mm/s or DCLL in the ranges of tens of cm/s). The present work analyses the PAV extraction efficiency dependency on the design parameters as optimum on-line Tritium Extraction System (TES). Three different models have been built for that purpose: one through physically refined 1D tritium transport computation using TMAP7 (unique simulation tool with QA for ITER); and two further detailed models on 2D/3D FEM tool (COMSOL Multi-physics 4.0). The geometry used in this work is a simplification of Fuskite{sup Registered-Sign} conceptual design developed at CIEMAT, consisting of a set of cylindrical and concentric {alpha}-Fe double membranes enclosing a vacuumed space and in contact with in-pipe flowing LiPb eutectic. The aim of this paper is to give the first steps to establish the optimal design parameters of a PAV and evaluate the state-of-the-art of these models.

  11. MISTRAL: A comprehensive model for tritium transport in lithium-base ceramics. Pt. 2

    International Nuclear Information System (INIS)

    Federici, G.; Raffray, A.R.; Abdou, M.A.

    1990-01-01

    A new tritium transport model called MISTRAL (Model for Investigative Studies of Tritium Release in Lithium Ceramics) has been developed to describe and predict the kinetics of tritium release in lithium ceramic materials for tritium breeding applications in fusion blankets. The model has transient capabilities and has been developed to analyze the full range of transient conditions produced in in-pile tritium recovery experiments and expected in fusion blankets. Calibration of the model against experiments has been done in parallel with its development in order to assess its predictive capabilities and to identify the ranges of potential applicability. The comparisons of the results available for lithium metasilicate and aluminate samples irradiated respectively in the two in-pile tritium recovery experiments LISA1 and MOZART are presented and discussed in this paper. They have been selected for the calibration of the codes as being good examples of various features relevant for tritium release analysis in ceramic breeders under different transient conditions such as change in temperature, purge gas composition and reactor power. (orig.)

  12. Environmental transport and long-term exposure for tritium released in the biosphere

    International Nuclear Information System (INIS)

    Bergman, R.; Bergstroem, U.; Evans, S.

    1979-01-01

    Global cycling of tritium is studied with regard to long-term exposure and dose. Dose and dose commitment are calculated for releases at different latitudes to the troposphere, land and upper ocean layer, with particular regard to effects from release into recipients of intermediate size as, for example, the Baltic Sea. The global transport of tritium appears to be governed by first order kinetics. Compartment models based on linear differential equation systems, as used in this study, should therefore be adequate. The realism and applicability of ecological compartment models are analysed with respect to completeness of the systems of reservoirs and pathways as well as accuracy in assumed reservoir sizes and exchange rates. By introducing different biospheric reservoirs and transfer mechanisms, important carriers and recipients are identified for the analysis of tritium released to air, land and water. Terrestrial biota and groundwater are shown to be significant both with regard to reservoir sizes and influence on the land-troposphere and land-sea exchange of tritium. Model studies regarding the conversion of HT to HTO in different biospheric reservoirs indicate that an atmospheric release of HT may yield up to 1.7 times the dose commitment obtained after release of the same amount of tritium as HTO. The global collective dose commitment from a tropospheric release of tritium is 0.002-0.004 man.rem per Ci depending on the latitude at the release point. Release to the surface ocean layers gives a ten times lower collective dose. (author)

  13. Mixed MHD convection and Tritium transport in fusion-relevant configurations

    International Nuclear Information System (INIS)

    Sposito, G.; Ciofalo, M.; Di Maio, P.A.; Vella, G.

    2005-01-01

    Mixed MHD flow and Tritium transport were computed for a slender poloidal duct, representative of a DEMO HCLL blanket element. 2-D flow and temperature fields were computed in the duct's cross section under the assumption of parallel, fully developed flow, while Tritium concentration C was found by solving a fully 3-D problem with simplifying assumptions at the duct's ends. The spatial distribution of C depended on the intensity and direction of the forced flow. Significant peak factors were obtained if the net flow rate was so low that re-circulation occurred; C maxima were attained near the walls for upward flow, in the core region for downward flow

  14. Investigation of tritium transport by the water courses from the territory of Krasnoyarsk MCC

    International Nuclear Information System (INIS)

    Nosov, A.V.; Martynova, A.M.; Shabanov, V.F.; Savitskij, Yu.V.; Shishlov, A.E.; Revenko, Yu.A.

    2001-01-01

    The problem of the Enisej river contamination as a result of tritium transport from the territory of the Krasnoyarsk Mining and Chemical Complex is discussed. The results of investigations realized for the Complex sewerage waters and streams running out from its territory and flowing into the Enisej river within the controlled area are analyzed. The investigations include hydrometric measurements of water flow rate, dosimetric measurements of of water stream profiles and sampling of water, bottom sediments, tidal soils, as well as hydrobionts for radioisotope and chemical analysis. Maximum tritium concentration revealed amounts to 125 Bq/l which is not dangerous from ecological viewpoint. The conclusion on necessity of the tritium monitoring in the zone affected by the Krasnoyarsk Mining and Chemical Complex is made [ru

  15. Behavioural economics, travel behaviour and environmental-transport policy

    NARCIS (Netherlands)

    Garcia-Sierra, M.; van den Bergh, J.C.J.M.; Miralles, C.

    2015-01-01

    The transport sector creates much environmental pressure. Many current policies aimed at reducing this pressure are not fully effective because the behavioural aspects of travellers are insufficiently recognised. Insights from behavioural economics can contribute to a better understanding of travel

  16. Evaluation of the Fate and Transport of Tritium Contaminated Groundwater from the 618-11 Burial Ground

    International Nuclear Information System (INIS)

    Vermeul, Vince R.; Bergeron, Marcel P.; Dresel, P EVAN.; Freeman, Eugene J.; Peterson, R E.; Thorne, Paul D.

    2005-01-01

    Tritium transport simulations were conducted to model the mechanisms associated with dilution, dispersion, and radioactive decay that attenuate the 618-11 Burial Ground tritium plume and limit the risk associated with exposure to the Columbia River and Energy Northwest water supply wells. A comparison of simulated and observed tritium concentrations at two downgradient monitoring wells indicated that the model was a reasonable representation of the tritium concentrations immediately downgradient of the site (699-13-3A) and near the leading edge of the plume (699-13-0A). This good match increased confidence in the conceptual model, its numeric implementation, and ultimately the validity of predictive simulations of tritium fate and transport. Three release scenarios were investigated to measure the impact of the tritium plume at primary receptor locations under different conditions. The three cases were (1) a pulse release of tritium from the burial ground that was the best fit between observed and simulated tritium concentrations; (2) a continuing, decaying source beneath the burial ground through 2015, the milestone for source removal under the River Corridor Closure Contract; and (3) a pulse release as in the best fit case but at twice the concentration. For the best fit case, the model predicts that the maximum tritium concentration will decline to below the drinking water standard by 2031 For the other two release scenarios, maximum tritium concentrations declined to below the drinking water standard by 2040 and 2037, respectively. Tritium from the 618-11 burial ground is not expected to migrate to the Columbia River or to the Energy Northwest water supply wells at concentrations that would pose a significant risk

  17. Evaluation of the Fate and Transport of Tritium Contaminated Groundwater from the 618-11 Burial Ground

    International Nuclear Information System (INIS)

    Vermeul, Vince R.; Bergeron, Marcel P.; Dresel, P Evan; Freeman, Eugene J.; Peterson, R E.; Thorne, Paul D.

    2005-01-01

    Tritium transport simulations were conducted to model the mechanisms associated with dilution, dispersion, and radioactive decay that attenuate the 618-11 tritium plume and limit the risk associated with exposure to the Columbia River and Energy Northwest water supply wells. A comparison of simulated and observed tritium concentrations at two downgradient monitoring wells indicated that the model was a reasonable representation of the tritium concentrations immediately downgradient of the site (699-13-3A) and near the leading edge of the plume (699-13-0A). This good match increased confidence in the conceptual model, its numeric implementation, and ultimately, the validity of predictive simulations of tritium fate and transport. Three release scenarios were investigated to measure the impact of the tritium plume at primary receptor locations under different conditions. The three cases were (1) a pulse release of tritium from the burial ground that was the best fit between observed and simulated tritium concentrations; (2) a continuing, decaying source beneath the burial ground through 2015, the milestone for source removal under the River Corridor Closure Contract; and (3) a pulse release as in the best fit case but at twice the concentration. For the best fit case, the model predicts that the maximum tritium concentration will decline to below the drinking water standard by 2031 For the other two release scenarios, maximum tritium concentrations declined to below the drinking water standard by 2040 and 2037, respectively. Tritium from the 618-11 burial ground is not expected to migrate to the Columbia River or to the Energy Northwest water supply wells at concentrations that would pose a significant risk

  18. Heat Exchanger Design Options and Tritium Transport Study for the VHTR System

    Energy Technology Data Exchange (ETDEWEB)

    Chang H. Oh; Eung S. Kim

    2008-09-01

    This report presents the results of a study conducted to consider heat exchanger options and tritium transport in a very high temperature reactor (VHTR) system for the Next Generation Nuclear Plant Project. The heat exchanger options include types, arrangements, channel patterns in printed circuit heat exchangers (PCHE), coolant flow direction, and pipe configuration in shell-and-tube designs. Study considerations include: three types of heat exchanger designs (PCHE, shell-and-tube, and helical coil); single- and two-stage unit arrangements; counter-current and cross flow configurations; and straight pipes and U-tube designs in shell-and-tube type heat exchangers. Thermal designs and simple stress analyses were performed to estimate the heat exchanger options, and the Finite Element Method was applied for more detailed calculations, especially for PCHE designs. Results of the options study show that the PCHE design has the smallest volume and heat transfer area, resulting in the least tritium permeation and greatest cost savings. It is theoretically the most reliable mechanically, leading to a longer lifetime. The two-stage heat exchanger arrangement appears to be safer and more cost effective. The recommended separation temperature between first and second stages in a serial configuration is 800oC, at which the high temperature unit is about one-half the size of the total heat exchanger core volume. Based on simplified stress analyses, the high temperature unit will need to be replaced two or three times during the plant’s lifetime. Stress analysis results recommend the off-set channel pattern configuration for the PCHE because stress reduction was estimated at up to 50% in this configuration, resulting in a longer lifetime. The tritium transport study resulted in the development of a tritium behavior analysis code using the MATLAB Simulink code. In parallel, the THYTAN code, previously performed by Ohashi and Sherman (2007) on the Peach Bottom data, was revived

  19. Underground Test Area Subproject Phase I Data Analysis Task. Volume VII - Tritium Transport Model Documentation Package

    Energy Technology Data Exchange (ETDEWEB)

    None

    1996-12-01

    Volume VII of the documentation for the Phase I Data Analysis Task performed in support of the current Regional Flow Model, Transport Model, and Risk Assessment for the Nevada Test Site Underground Test Area Subproject contains the tritium transport model documentation. Because of the size and complexity of the model area, a considerable quantity of data was collected and analyzed in support of the modeling efforts. The data analysis task was consequently broken into eight subtasks, and descriptions of each subtask's activities are contained in one of the eight volumes that comprise the Phase I Data Analysis Documentation.

  20. Scoping calculations for groundwater transport of tritium from the Gnome Site, New Mexico

    International Nuclear Information System (INIS)

    Pohlmann, K.; Andricevic, R.

    1994-08-01

    Analytic solutions are employed to investigate potential groundwater transport of tritium from a radioactive tracer site near the Project Gnome site in southeastern New Mexico. The tracer test was conducted in 1963 and introduced significant quantities of radionuclides to the transmissive and laterally continuous Culebra dolomite. Groundwater in the Culebra near Gnome travels toward a regional discharge point at the Pecos River, a distance of about 10 to 15 km, depending on flow path. Groundwater transport of radionuclides from the Gnome site is therefore of interest due to the proximity of the accessible environment and the 31-year time period during which migration is likely to have occurred. The analytical stochastic solutions used incorporate the heterogeneity observed in the Culebra by treating transmissivity as a spatially correlated random field. The results indicate that significant spreading of tritium will occur in the Culebra dolomite as a result of the combination of relatively high transmissivity, high spatial variability, and high spatial correlation of transmissivity. Longitudinal spreading may cause a very small fraction of tritium mass to arrive at the Pecos River within the 31 years since the tracer test. However, dilution and transverse dispersion will act to distribute this mass over a very large volume, thereby reducing groundwater concentrations. Despite the high degree of spreading, the calculations indicate that most of the tritium remains near the source. At present, the center of mass is estimated to have moved approximately 260 m downgradient of the test location and about 95 percent of the mass is estimated to have remained within about 1 km downgradient

  1. Parametric analysis of LIBRETTO-4 and 5 in-pile tritium transport model on EcosimPro

    Energy Technology Data Exchange (ETDEWEB)

    Alcalde, Pablo Martínez, E-mail: pablomiguel.martinez@externos.ciemat.es [Universidad Nacional de Educación a Distancia (UNED), c/Juan del Rosal 12, 28040 Madrid (Spain); Moreno, Carlos; Ibarra, Ángel [CIEMAT, Avda. Complutense 40, 28040 Madrid (Spain)

    2014-10-15

    Highlights: • Introduction of a new tritium transport model of LIBRETTO-4 and 5 on EcosimPro{sup ®}. • Analysis of model input parameter and variable sensitivities and effects on tritium simulated fluxes. • Demonstrations of high tritium out-flux dependencies on lead-lithium parameters. • Rough fitting achievements proposed by Li17Pb solubility or recombination increase. - Abstract: A new model for LIBRETTO-4/1, 4/2 and 5 experiments have been developed on ECOSIMPro{sup ©} tool to simulate tritium in-pile breeding and transport into two separate purge gas channels with He + 0.1%H{sub 2}. Release from lead lithium eutectic plenum with coupled permeation through an austenitic steel wall on the first and single permeation through EUROFER-97 in the temperature ranges of 300–550 °C can be simulated tuning the transport parameters involved. A parametric study has been performed to reduce the degrees of freedom and to determine the error caused in the simulation due to the uncertainty in experimental input data. The information obtained is essential for the experimental benchmarking. The Tritium Permeation Percentage (TPP) is an output calculated parameter with low variations between 2 and 6% along the whole experimental time easy to compare (730 Full Power Days for LIBRETTO-4 and 520 for 5). Tritium transport parameter ranges verifying this output are defined herein.

  2. TRITIUM PERMEATION AND TRANSPORT IN THE GASOLINE PRODUCTION SYSTEM COUPLED WITH HIGH TEMPERATURE GAS-COOLED REACTORS (HTGRS)

    Energy Technology Data Exchange (ETDEWEB)

    Chang H. Oh; Eung S. Kim; Mike Patterson

    2011-05-01

    This paper describes scoping analyses on tritium behaviors in the HTGR-integrated gasoline production system, which is based on a methanol-to-gasoline (MTG) plant. In this system, the HTGR transfers heat and electricity to the MTG system. This system was analyzed using the TPAC code, which was recently developed by Idaho National Laboratory. The global sensitivity analyses were performed to understand and characterize tritium behaviors in the coupled HTGR/MTG system. This Monte Carlo based random sampling method was used to evaluate maximum 17,408 numbers of samples with different input values. According to the analyses, the average tritium concentration in the product gasoline is about 3.05×10-3 Bq/cm3, and 62 % cases are within the tritium effluent limit (= 3.7x10-3 Bq/cm3[STP]). About 0.19% of released tritium is finally transported from the core to the gasoline product through permeations. This study also identified that the following four parameters are important concerning tritium behaviors in the HTGR/MTG system: (1) tritium source, (2) wall thickness of process heat exchanger, (3) operating temperature, and (4) tritium permeation coefficient of process heat exchanger. These four parameters contribute about 95 % of the total output uncertainties. This study strongly recommends focusing our future research on these four parameters to improve modeling accuracy and to mitigate tritium permeation into the gasol ine product. If the permeation barrier is included in the future study, the tritium concentration will be significantly reduced.

  3. Transport of tritium contamination to the atmosphere in an arid environment

    Science.gov (United States)

    Garcia, C. Amanda; Andraski, Brian J.; Johnson, Michael J.; Stonestrom, David A.; Michel, Robert L.; Cooper, C.A.; Wheatcraft, S.W.

    2009-01-01

    Soil–plant–atmosphere interactions strongly influence water movement in desert unsaturated zones, but little is known about how such interactions affect atmospheric release of subsurface water-borne contaminants. This 2-yr study, performed at the U.S. Geological Survey's Amargosa Desert Research Site in southern Nevada, quantified the magnitude and spatiotemporal variability of tritium (3H) transport from the shallow unsaturated zone to the atmosphere adjacent to a low-level radioactive waste (LLRW) facility. Tritium fluxes were calculated as the product of 3H concentrations in water vapor and respective evaporation and transpiration water-vapor fluxes. Quarterly measured 3H concentrations in soil water vapor and in leaf water of the dominant creosote-bush [Larrea tridentata (DC.) Coville] were spatially extrapolated and temporally interpolated to develop daily maps of contamination across the 0.76-km2 study area. Maximum plant and root-zone soil concentrations (4200 and 8700 Bq L−1, respectively) were measured 25 m from the LLRW facility boundary. Continuous evaporation was estimated using a Priestley–Taylor model and transpiration was computed as the difference between measured eddy-covariance evapotranspiration and estimated evaporation. The mean evaporation/transpiration ratio was 3:1. Tritium released from the study area ranged from 0.12 to 12 μg d−1 and totaled 1.5 mg (8.2 × 1010 Bq) over 2 yr. Tritium flux variability was driven spatially by proximity to 3H source areas and temporally by changes in 3H concentrations and in the partitioning between evaporation and transpiration. Evapotranspiration removed and limited penetration of precipitation beneath native vegetation and fostered upward movement and release of 3H from below the root zone.

  4. A two-dimensional simulation of tritium transport in the vadose zone at the Nevada Test site

    Energy Technology Data Exchange (ETDEWEB)

    Ross, W.C.; Wheatcraft, S.W.

    1994-09-01

    The site of a 0.75-kiloton underground nuclear explosion, the Cambric event, was selected for the study of radionuclide transport in the hydrologic environment. Water samples from RNM-2S, a well located 91 m from Cambric, have been analyzed for tritium and other radionuclides since the initiation of pumping. Water from RNM-2S flows to Frenchman Lake via an unlined canal. Flume data indicate canal transmission losses of approximately 2m{sup 3}/day/meter of canal. To determine if infiltrating canal water might be recirculated by RNM-2S, and therefore provide an additional radionuclide input to water samples collected at RNM-2S, a two-dimensional variably saturated solute transport computer model (SATURN, Huyakorn et al., 1983) was used to simulate the movement of tritium from the canal to the water table. Results indicate that recirculated canal water has not had a significant effect on the breakthrough of tritium at RNM-2S.

  5. Modeling tritium transport through a deep unsaturated zone in an arid environment

    Science.gov (United States)

    Mayers, C.J.; Andraski, Brian J.; Cooper, C.A.; Wheatcraft, S.W.; Stonestrom, David A.; Michel, R.L.

    2005-01-01

    Understanding transport of tritium (3H) in unsaturated zones is critical to evaluating options for waste isolation. Tritium typically is a large component of low-level radioactive waste (LLRW). Studies at the U.S. Geological Survey's Amargosa Desert Research Site (ADRS) in Nevada investigate 3H transport from a closed LLRW facility. Two boreholes are 100 and 160 m from the nearest waste trench and extend to the water table at 110 m. Soil-water vapor samples from the deep boreholes show elevated levels of 3H at all depths. The objectives of this study were to (i) test source thermal and gas-advection mechanisms driving 3H transport and (ii) evaluate model sensitivity to these mechanisms and to selected physical and hydraulic properties including porosity, tortuosity, and anisotropy. A two-dimensional numerical model incorporated a non-isothermal, heterogeneous domain of the unsaturated zone and instantaneous isotopic equilibrium. The TOUGH2 code was used; however, it required modification to account for temperature dependence of both the Henry's law equilibrium constant and isotopic fractionation with respect to tritiated water. Increases in source temperature, pressure, and porosity enhanced 3H migration, but failed to match measured 3H distributions. All anisotropic simulations with a source pressure component resembled, in shape, the upper portion of the 3H distribution of the nearest borehole. Isotopic equilibrium limited migration of 3H, while effects of radioactive decay were negligible. A 500 Pa pressure increase above ambient pressure in conjunction with a high degree of anisotropy (1:100) was necessary for simulated 3H transport to reach the nearest borehole.

  6. Safe handling of tritium

    International Nuclear Information System (INIS)

    1991-01-01

    The main objective of this publication is to provide practical guidance and recommendations on operational radiation protection aspects related to the safe handling of tritium in laboratories, industrial-scale nuclear facilities such as heavy-water reactors, tritium removal plants and fission fuel reprocessing plants, and facilities for manufacturing commercial tritium-containing devices and radiochemicals. The requirements of nuclear fusion reactors are not addressed specifically, since there is as yet no tritium handling experience with them. However, much of the material covered is expected to be relevant to them as well. Annex III briefly addresses problems in the comparatively small-scale use of tritium at universities, medical research centres and similar establishments. However, the main subject of this publication is the handling of larger quantities of tritium. Operational aspects include designing for tritium safety, safe handling practice, the selection of tritium-compatible materials and equipment, exposure assessment, monitoring, contamination control and the design and use of personal protective equipment. This publication does not address the technologies involved in tritium control and cleanup of effluents, tritium removal, or immobilization and disposal of tritium wastes, nor does it address the environmental behaviour of tritium. Refs, figs and tabs

  7. Tritium technology. A Canadian overview

    International Nuclear Information System (INIS)

    Hemmings, R.L.

    2002-01-01

    An overview of the various tritium research and operational activities in Canada is presented. These activities encompass tritium processing and recovery, tritium interactions with materials, and tritium health and safety. Many of these on-going activities form a sound basis for the tritium use and handling aspects of the ITER project. Tritium management within the CANDU heavy water reactor, associated detritiation facilities, research and development facilities, and commercial industry and improving the understanding of tritium behaviour in humans and the environment remain the focus of a long-standing Canadian interest in tritium. While there have been changes in the application of this knowledge and experience over time, the operating experience and the supporting research and development continue to provide for improved plant and facility operations, an improved understanding of tritium safety issues, and improved products and tools that facilitate tritium management. (author)

  8. Regional groundwater flow and tritium transport modeling and risk assessment of the underground test area, Nevada Test Site, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    None

    1997-10-01

    The groundwater flow system of the Nevada Test Site and surrounding region was evaluated to estimate the highest potential current and near-term risk to the public and the environment from groundwater contamination downgradient of the underground nuclear testing areas. The highest, or greatest, potential risk is estimated by assuming that several unusually rapid transport pathways as well as public and environmental exposures all occur simultaneously. These conservative assumptions may cause risks to be significantly overestimated. However, such a deliberate, conservative approach ensures that public health and environmental risks are not underestimated and allows prioritization of future work to minimize potential risks. Historical underground nuclear testing activities, particularly detonations near or below the water table, have contaminated groundwater near testing locations with radioactive and nonradioactive constituents. Tritium was selected as the contaminant of primary concern for this phase of the project because it is abundant, highly mobile, and represents the most significant contributor to the potential radiation dose to humans for the short term. It was also assumed that the predicted risk to human health and the environment from tritium exposure would reasonably represent the risk from other, less mobile radionuclides within the same time frame. Other contaminants will be investigated at a later date. Existing and newly collected hydrogeologic data were compiled for a large area of southern Nevada and California, encompassing the Nevada Test Site regional groundwater flow system. These data were used to develop numerical groundwater flow and tritium transport models for use in the prediction of tritium concentrations at hypothetical human and ecological receptor locations for a 200-year time frame. A numerical, steady-state regional groundwater flow model was developed to serve as the basis for the prediction of the movement of tritium from the

  9. Calibration of a transient transport model to tritium data in streams and simulation of groundwater ages in the western Lake Taupo catchment, New Zealand

    Directory of Open Access Journals (Sweden)

    M. A. Gusyev

    2013-03-01

    Full Text Available Here we present a general approach of calibrating transient transport models to tritium concentrations in river waters developed for the MT3DMS/MODFLOW model of the western Lake Taupo catchment, New Zealand. Tritium has a known pulse-shaped input to groundwater systems due to the bomb tritium in the early 1960s and, with its radioactive half-life of 12.32 yr, allows for the determination of the groundwater age. In the transport model, the tritium input (measured in rainfall passes through the groundwater system, and the simulated tritium concentrations are matched to the measured tritium concentrations in the river and stream outlets for the Waihaha, Whanganui, Whareroa, Kuratau and Omori catchments from 2000–2007. For the Kuratau River, tritium was also measured between 1960 and 1970, which allowed us to fine-tune the transport model for the simulated bomb-peak tritium concentrations. In order to incorporate small surface water features in detail, an 80 m uniform grid cell size was selected in the steady-state MODFLOW model for the model area of 1072 km2. The groundwater flow model was first calibrated to groundwater levels and stream baseflow observations. Then, the transient tritium transport MT3DMS model was matched to the measured tritium concentrations in streams and rivers, which are the natural discharge of the groundwater system. The tritium concentrations in the rivers and streams correspond to the residence time of the water in the groundwater system (groundwater age and mixing of water with different age. The transport model output showed a good agreement with the measured tritium values. Finally, the tritium-calibrated MT3DMS model is applied to simulate groundwater ages, which are used to obtain groundwater age distributions with mean residence times (MRTs in streams and rivers for the five catchments. The effect of regional and local hydrogeology on the simulated groundwater ages is investigated by demonstrating groundwater ages

  10. Evaluation of tritium transport in the biomass-fusion hybrid system and its environmental impact

    Energy Technology Data Exchange (ETDEWEB)

    Namba, Kyosuke [Graduate School of Energy Science, Kyoto University, Kyoto (Japan); Kasada, Ryuta, E-mail: r-kasada@iae.kyoto-u.ac.jp [Institute of Advanced Energy, Kyoto University, Kyoto (Japan); Konishi, Satoshi [Institute of Advanced Energy, Kyoto University, Kyoto (Japan); Yamamoto, Yasushi [Faculty of Engineering Science, Kansai University, Osaka (Japan)

    2015-10-15

    Highlights: • We assumed that tritium migrates from biomass hybrid fusion system to fuel cell vehicles. • We developed a seven-compartment model to describe the water flow and tritium in an urban area Osaka. • Tritium concentration of surface soil water run by 4 Bq/L level after 60 years later. • The tritium does not deserve health hazard but easily detectable in the environment. - Abstract: The behavior of tritium contained in the biofuel produced by the fusion energy is analyzed. Hydrogen product is contaminated with tritium from breeding blanket of fusion plant within the regulation limit and released to atmosphere when used for fuel cell vehicles. In the model city, Osaka, seven-compartment model describes the behavior of exhausted tritium by adapting the environment water flow and its migration was analyzed with STELLA system dynamics code. Tritium (HTO) with a concentration of 5000 Bq//m{sup 3} exhausted from the running vehicle increases decades and reaches steady state after about 50 years, at around 40 Bq/m{sup 3} in atmosphere and 4 Bq/L in surface soil water that does not deserve health hazard, however causes contamination of large populated area.

  11. Tritium transport modeling at system level for the EUROfusion dual coolant lithium-lead breeding blanket

    Science.gov (United States)

    Urgorri, F. R.; Moreno, C.; Carella, E.; Rapisarda, D.; Fernández-Berceruelo, I.; Palermo, I.; Ibarra, A.

    2017-11-01

    The dual coolant lithium lead (DCLL) breeding blanket is one of the four breeder blanket concepts under consideration within the framework of EUROfusion consortium activities. The aim of this work is to develop a model that can dynamically track tritium concentrations and fluxes along each part of the DCLL blanket and the ancillary systems associated to it at any time. Because of tritium nature, the phenomena of diffusion, dissociation, recombination and solubilisation have been modeled in order to describe the interaction between the lead-lithium channels, the structural material, the flow channel inserts and the helium channels that are present in the breeding blanket. Results have been obtained for a pulsed generation scenario for DEMO. The tritium inventory in different parts of the blanket, the permeation rates from the breeder to the secondary coolant and the amount of tritium extracted from the lead-lithium loop have been computed. Results present an oscillating behavior around mean values. The obtained average permeation rate from the liquid metal to the helium is 1.66 mg h-1 while the mean tritium inventory in the whole system is 417 mg. Besides the reference case results, parametric studies of the lead-lithium mass flow rate, the tritium extraction efficiency and the tritium solubility in lead-lithium have been performed showing the reaction of the system to the variation of these parameters.

  12. Overview of tritium fast-fission yields

    International Nuclear Information System (INIS)

    Tanner, J.E.

    1981-03-01

    Tritium production rates are very important to the development of fast reactors because tritium may be produced at a greater rate in fast reactors than in light water reactors. This report focuses on tritium production and does not evaluate the transport and eventual release of the tritium in a fast reactor system. However, if an order-of-magnitude increase in fast fission yields for tritium is confirmed, fission will become the dominant production source of tritium in fast reactors

  13. An interdisciplinary approach for the transport of tritium in animals and human dosimetry

    International Nuclear Information System (INIS)

    Galeriu, Dan; Melintescu, Anca; Takeda, Hiroshi; Beresford, Nick

    2007-01-01

    Further development of nuclear energy needs robust radioecological models for predicting the transfer of radionuclides in the environment and robust dose conversion coefficients. Concerns of increased risk from tritium intakes by humans have been raised in the past years, from both tritiated water and organically bound tritium. In the last few years we have concentrated on modelling tritium (and carbon) transfer in mammals, aquatic flora and fauna and birds. We use basic processes from environmental physics, animal physiology, nutrition and metabolism. Recent progresses are reported, in conjunction with international cooperation within IAEA programmes and other organisations. (author)

  14. Public transport optimisation emphasising passengers’ travel behaviour

    DEFF Research Database (Denmark)

    Jensen, Jens Parbo

    bus lines’ departure time from the initial station, and thereby reducing the waiting time passengers experience at any of the particular bus line’s transfer stops. The offset changing heuristic is built on a Tabu Search framework, which is applied for its superiority for the particular problem type......Passengers in public transport complaining about their travel experiences are not uncommon. This might seem counterintuitive since several operators worldwide are presenting better key performance indicators year by year. The present PhD study focuses on developing optimisation algorithms...... to enhance the operations of public transport while explicitly emphasising passengers’ travel behaviour and preferences. Similar to economic theory, interactions between supply and demand are omnipresent in the context of public transport operations. In public transport, the demand is represented...

  15. Environmental tritium transport model. Application to the dose evaluation for members of the public

    International Nuclear Information System (INIS)

    Murphy, C.E. Jr.

    1984-01-01

    A model of tritium dispersion and cycling in terrestial ecosystems surrounding an atmospheric source of tritium is presented. The model structure is described. Results of simulations of three release cases are used to illustrate the dynamics of the model. The three cases are: a release of 100% TH, a release of 100% THO, and a release of 50% TH and 50% THO. The TH release is characterized by having a lower total retention of tritium in the ecosystem than the THO case. However, a greater fraction (but lower absolute amount) of the tritium in the TH release is found in the organic component of vegetation and the animals that feed on the vegetation. 24 references, 1 table

  16. Environmental transportation of tritium and estimation of site-specific model parameters for Kaiga site, India.

    Science.gov (United States)

    Reji, T K; Ravi, P M; Ajith, T L; Dileep, B N; Hegde, A G; Sarkar, P K

    2012-04-01

    Tritium content in air moisture, soil water, rain water and plant water samples collected around the Kaiga site, India was estimated and the scavenging ratio, wet deposition velocity and ratio of specific activities of tritium between soil water and air moisture were calculated and the results are interpreted. Scavenging ratio was found to vary from 0.06 to 1.04 with a mean of 0.46. The wet deposition velocity of tritium observed in the present study was in the range of 3.3E-03 to 1.1E-02 m s(-1) with a mean of 6.6E-03 m s(-1). The ratio of specific activity of tritium in soil moisture to that in air moisture ranged from 0.17 to 0.95 with a mean of 0.49. The specific activity of tritium in plant water in this study varied from 73 to 310 Bq l(-1). The present study is very useful for understanding the process and modelling of transfer of tritium through air/soil/plant system at the Kaiga site.

  17. Simulation of Tritium Transport and Groundwater Age in a Variably Saturated 3D Model, Lake Rotorua Catchment, New Zealand

    Science.gov (United States)

    Daughney, C.; Toews, M. W.; Morgenstern, U.; Cornaton, F. J.; Jackson, B. M.

    2013-12-01

    Lake Rotorua is a focus of culture and tourism in New Zealand. The lake's water quality has declined since the 1970s, partly due to nutrient inputs that reach the lake via the groundwater system. Improved land use management within the catchment requires prediction of the spatial variations of groundwater transit time from land surface to the lake, and from this the prediction of current and future nutrient inflows to the lake. This study combines the two main methods currently available for determination of water age: numerical groundwater models and hydrological tracers. A steady-state 3D finite element model was constructed to simulate groundwater flow and transport of tritium and age at the catchment scale (555 km2). The model materials were defined using a 3D geologic model and included ignimbrites, rhyolites, alluvial and lake bottom sediments. The steady-state saturated groundwater flow model was calibrated using observed groundwater levels in boreholes (111 locations) and stream flow measurements from groundwater-fed streams and springs (61 locations). Hydraulic conductivities and Cauchy boundary conditions associated with the streams, springs and lake were parameterized. The transport parameters for the model were calibrated using 191 tritium samples from 105 locations (springs, streams and boreholes), with most locations having two sample dates. The transport model used steady-state flow, but simulated the transient transport and decay of tritium from rainfall recharge between 1945 and 2012. An additional 1D unsaturated sub-model was added to account for tritium decay from the ground surface to the water table. The sub-model is linked on top of the 3D model, and uses the water table depths and material properties from the 3D model. The adjustable calibration parameters for the transport model were porosity and van Genuchten parameters related to the unsaturated sub-models. Calibration of the flow model was achieved using a combination of automated least

  18. Isolation of a spontaneous CHO amino acid transport mutant by a combination of tritium suicide and replica plating

    International Nuclear Information System (INIS)

    Dantzig, A.H.; Slayman, C.W.; Adelberg, E.A.

    1982-01-01

    A spontaneous transport mutant of Chinese hamster ovary cells, CHY-1, was isolated by a combination of [ 3 H]proline suicide and replica plating. The mutant took up less tritium than the parent, resulting in a lower killing rate during storage. Transport by four separate amino acid transport systems (A, ASC, L, Ly+) was examined. The CHY-1 mutant exhibited normal uptake via the ASC, L, and Ly+ systems. By contrast, uptake of the most specific substrate of the A system, 2-(methylamino)-isobutyric acid, was significantly reduced at low, but not high, concentrations, due to a 3.5-fold increase in Km and a 1.5-fold increase in Vmax. Taken together, these data suggest that the CHY-1 mutation may be in the structural gene coding for the A transport protein. The tritium suicide procedure is discussed, and general equations are derived to predict the maximum storage time for the survival of one mutant cell and the optimum size of the cell population for maximum mutant enrichment

  19. Environmental Tritium.

    OpenAIRE

    1984-01-01

    Environmental tritium was first observed in a helium fraction at a liquid air production facility in Germany in 1949. During the 1950s and early 1960s, huge amounts of artificial tritium were released into the atmosphere by nuclear testing. The environmental tritium level increased to more than 200 times the natural tritium level. Since the signing of a test ban treaty in 1963, the environmental tritium level has decreased, and analysis of recent Japanese rain samples has shown that the envir...

  20. Bounded rational choice behaviour: applications in transport

    DEFF Research Database (Denmark)

    Jensen, Anders Fjendbo

    2016-01-01

    Even though the theory of rational behaviour has been challenged for almost 100 years, the dominant approach within the field of transport has been based upon the assumptions of neoclassical economics that we live in a world of rational decision makers who always have perfect knowledge and aim to...... and limited processing may occur due to time constraints, low involvement in the decision at hand, relying on habits or the task requiring too high a mental effort....... to maximise some subjective measure. Where other fields, for example within the social sciences and psychology, have made serious efforts to explore alternative models derived from principles of bounded rationality, this direction has begun to take speed within transport applications only recently. Bounded...

  1. Tritium Transport at the Rulison Site, a Nuclear-stimulated Low-permeability Natural Gas Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    C. Cooper; M. Ye; J. Chapman

    2008-04-01

    The U.S. Department of Energy (DOE) and its predecessor agencies conducted a program in the 1960s and 1970s that evaluated technology for the nuclear stimulation of low-permeability natural gas reservoirs. The second project in the program, Project Rulison, was located in west-central Colorado. A 40-kiltoton nuclear device was detonated 2,568 m below the land surface in the Williams Fork Formation on September 10, 1969. The natural gas reservoirs in the Williams Fork Formation occur in low permeability, fractured sandstone lenses interbedded with shale. Radionuclides derived from residual fuel products, nuclear reactions, and activation products were generated as a result of the detonation. Most of the radionuclides are contained in a cooled, solidified melt glass phase created from vaporized and melted rock that re-condensed after the test. Of the mobile gas-phase radionuclides released, tritium ({sup 3}H or T) migration is of most concern. The other gas-phase radionuclides ({sup 85}Kr, {sup 14}C) were largely removed during production testing in 1969 and 1970 and are no longer present in appreciable amounts. Substantial tritium remained because it is part of the water molecule, which is present in both the gas and liquid (aqueous) phases. The objectives of this work are to calculate the nature and extent of tritium contamination in the subsurface from the Rulison test from the time of the test to present day (2007), and to evaluate tritium migration under natural-gas production conditions to a hypothetical gas production well in the most vulnerable location outside the DOE drilling restriction. The natural-gas production scenario involves a hypothetical production well located 258 m horizontally away from the detonation point, outside the edge of the current drilling exclusion area. The production interval in the hypothetical well is at the same elevation as the nuclear chimney created by the detonation, in order to evaluate the location most vulnerable to

  2. Hydrogeology and tritium transport in Chicken Creek Canyon,Lawrence Berkeley National Laboratory, Berkeley, California

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Preston D.; Javandel, Iraj

    2007-10-31

    This study of the hydrogeology of Chicken Creek Canyon wasconducted by the Environmental Restoration Program (ERP) at LawrenceBerkeley National Laboratory (LBNL). This canyon extends downhill fromBuilding 31 at LBNL to Centennial Road below. The leading edge of agroundwater tritium plume at LBNL is located at the top of the canyon.Tritium activities measured in this portion of the plume during thisstudy were approximately 3,000 picocuries/liter (pCi/L), which issignificantly less than the maximum contaminant level (MCL) for drinkingwaterof 20,000 pCi/L established by the Environmental ProtectionAgency.There are three main pathways for tritium migration beyond theLaboratory s boundary: air, surface water and groundwater flow. Thepurpose of this report is to evaluate the groundwater pathway.Hydrogeologic investigation commenced with review of historicalgeotechnical reports including 35 bore logs and 27 test pit/trench logsas well as existing ERP information from 9 bore logs. This was followedby field mapping of bedrock outcrops along Chicken Creek as well asbedrock exposures in road cuts on the north and east walls of the canyon.Water levels and tritium activities from 6 wells were also considered.Electrical-resistivity profiles and cone penetration test (CPT) data werecollected to investigate the extent of an interpreted alluvial sandencountered in one of the wells drilled in this area. Subsequent loggingof 7 additional borings indicated that this sand was actually anunusually well-sorted and typically deeply weathered sandstone of theOrinda Formation. Wells were installed in 6 of the new borings to allowwater level measurement and analysis of groundwater tritium activity. Aslug test and pumping tests were also performed in the wellfield.

  3. An integrated model of tritium transport and corrosion in Fluoride Salt-Cooled High-Temperature Reactors (FHRs) – Part I: Theory and benchmarking

    Energy Technology Data Exchange (ETDEWEB)

    Stempien, John D., E-mail: john.stempien@inl.gov; Ballinger, Ronald G., E-mail: hvymet@mit.edu; Forsberg, Charles W., E-mail: cforsber@mit.edu

    2016-12-15

    Highlights: • A model was developed for use with FHRs and benchmarked with experimental data. • Model results match results of tritium diffusion experiments. • Corrosion simulations show reasonable agreement with molten salt loop experiments. • This is the only existing model of tritium transport and corrosion in FHRs. • Model enables proposing and evaluating tritium control options in FHRs. - Abstract: The Fluoride Salt-Cooled High-Temperature Reactor (FHR) is a pebble bed nuclear reactor concept cooled by a liquid fluoride salt known as “flibe” ({sup 7}LiF-BeF{sub 2}). A model of TRITium Diffusion EvolutioN and Transport (TRIDENT) was developed for use with FHRs and benchmarked with experimental data. TRIDENT is the first model to integrate the effects of tritium production in the salt via neutron transmutation, with the effects of the chemical redox potential, tritium mass transfer, tritium diffusion through pipe walls, tritium uptake by graphite, selective chromium attack by tritium fluoride, and corrosion product mass transfer. While data from a forced-convection polythermal loop of molten salt containing tritium did not exist for comparison, TRIDENT calculations were compared to data from static salt diffusion tests in flibe and flinak (0.465LiF-0.115NaF-0.42KF) salts. In each case, TRIDENT matched the transient and steady-state behavior of these tritium diffusion experiments. The corrosion model in TRIDENT was compared against the natural convection flow-loop experiments at the Oak Ridge National Laboratory (ORNL) from the 1960s and early 1970s which used Molten Salt Reactor Experiment (MSRE) fuel-salt containing UF{sub 4}. Despite the lack of data required by TRIDENT for modeling the loops, some reasonable results were obtained. The TRIDENT corrosion rates follow the experimentally observed dependence on the square root of the product of the chromium solid-state diffusion coefficient with time. Additionally the TRIDENT model predicts mass

  4. Development of a low tritium partial pressure permeation system for mass transport measurement in lead lithium eutectic

    International Nuclear Information System (INIS)

    Pawelko, R.; Shimada, M.; Katayama, K.; Fukada, S.; Terai, T.

    2014-01-01

    A new experimental system designed to investigate tritium mass transfer properties in materials important to fusion technology is operational at the Safety and Tritium Applied Research (STAR) facility located at the Idaho National Laboratory (INL). The tritium permeation measurement system was developed as part of the Japan/US TITAN collaboration to investigate tritium mass transfer properties in liquid lead lithium eutectic (LLE) alloy. The system is similar to a hydrogen/deuterium permeation measurement system developed at Kyushu University and also incorporates lessons learned from previous tritium permeation experiments conducted at the STAR facility. This paper describes the experimental system that is configured specifically to measure tritium mass transfer properties at low tritium partial pressures. We present preliminary tritium permeation results for α-Fe and α-Fe/LLE samples at 600degC and at tritium partial pressures between 1.0E-3 and 2.4 Pain helium. The preliminary results are compared with literature data. (author)

  5. Use of tritium to predict soluble pollutants transport in Ebro River waters (Spain).

    Science.gov (United States)

    Pujol, L; Sanchez-Cabeza, J A

    2000-05-01

    The Ebro River, in Northeast Spain, discharges into the Mediterranean Sea after flowing through several large cities and agricultural, mining and industrial areas. The Ascó nuclear power plant (NPP) is located in its lower section and comprises two pressurised water reactor units, from which low-level liquid radioactive waste is released to river waters under authority control. Tritium routinely released by the NPP was used as a radiotracer to determine the longitudinal dispersion coefficient and velocity of the river waters. Several field experiments, in co-ordination with the NPP, were carried out during 1991 and 1992. During each field experiment, the flow rate was kept constant by dams located upstream from the NPP. After each tritium release, water was sampled downstream at periodic intervals over several hours and tritium was measured with a low-background liquid scintillation counter. Velocity and dispersion coefficient were determined in river waters for several river discharges using an analytical, box-type and numerical approach to solve the one-dimensional advection-diffusion equation. The set of calibrated parameters was used to predict the displacement and dispersion of soluble pollutants in river waters. Velocity was determined as a function of river discharge and river slope, and dispersion coefficient was determined as a function of distance. Finally, sensitivity of the model predictions was studied and uncertainties of the fitted parameters were estimated.

  6. Tritium conference days; Journees tritium

    Energy Technology Data Exchange (ETDEWEB)

    Garnier-Laplace, J.; Lebaron-Jacobs, L.; Sene, M.; Devin, P.; Chretien, V.; Le Guen, B.; Guetat, Ph.; Baglan, N.; Ansoborlo, E.; Boyer, C.; Masson, M.; Bailly-Du-Bois, P.; Jenkinson, St.; Wakeford, R.; Saintigny, Y.; Romeo, P.H.; Thompson, P.; Leterq, D.; Chastagner, F.; Cortes, P.; Philippe, M.; Paquet, F.; Fournier, M.

    2009-07-01

    This document gathers the slides of the available presentations given during this conference day. Twenty presentations out of 21 are assembled in the document and deal with: 1 - tritium in the environment (J. Garnier-Laplace); 2 - status of knowledge about tritium impact on health (L. Lebaron-Jacobs); 3 - tritium, discrete but present everywhere (M. Sene); 4 - management of tritium effluents from Areva NC La Hague site - related impact and monitoring (P. Devin); 5 - tritium effluents and impact in the vicinity of EDF's power plants (V. Chretien and B. Le Guen); 6 - contribution of CEA-Valduc centre monitoring to the knowledge of atmospheric tritiated water transfers to the different compartments of the environment (P. Guetat); 7 - tritium analysis in environment samples: constraints and means (N. Baglan); 8 - organically-linked tritium: the analyst view (E. Ansoborlo); 9 - study of tritium transfers to plants via OBT/HTO{sub air} and OBT/HTO{sub free} (C. Boyer); 10 - tritium in the British Channel (M. Masson and P. Bailly-Du-Bois); 11 - tritium in British coastal waters (S. Jenkinson); 12 - recent results from epidemiology (R. Wakeford); 13 - effects of tritiated thymidine on hematopoietic stem cells (P.H. Romeo); 14 - tritium management issue in Canada: the point of view from authorities (P. Thompson); 15 - experience feedback of the detritiation process of Valduc centre (D. Leterq); 16 - difficulties linked with tritiated wastes confinement (F. Chastagner); 17 - optimisation of tritium management in the ITER project (P. Cortes); 18 - elements of thought about the management of tritium generated by nuclear facilities (M. Philippe); 19 - CIPR's position about the calculation of doses and risks linked with tritium exposure (F. Paquet); 20 - tritium think tanks (M. Fournier). (J.S.)

  7. Investigation of tritium inventory and permeation behaviour in the liquid breeder blanket concept of Demo as a function of design and material parameters

    International Nuclear Information System (INIS)

    Tominetti, S.; Perujo, A.; Reiter, F.

    1991-01-01

    A numerical code has been used to estimate the time dependence of tritium inventory and of tritium transport into the coolant, into the first wall boxes and through the liquid breeder in the Pb-17Li blanket concept of DEMO. Several issues in both design and material parameters have been considered and the effect on inventory and permeation of coatings with low surface recombination coefficient and/or low diffusivity at various surfaces of the structural material has been studied. TiC has been chosen as reference material for these calculations and a general database on coating efficiency as a function of its properties has also been produced on the basis of TiC data

  8. Tritium Suicide Selection Identifies Proteins Involved in the Uptake and Intracellular Transport of Sterols in Saccharomyces cerevisiae▿

    Science.gov (United States)

    Sullivan, David P.; Georgiev, Alexander; Menon, Anant K.

    2009-01-01

    Sterol transport between the plasma membrane (PM) and the endoplasmic reticulum (ER) occurs by a nonvesicular mechanism that is poorly understood. To identify proteins required for this process, we isolated Saccharomyces cerevisiae mutants with defects in sterol transport. We used Upc2-1 cells that have the ability to take up sterols under aerobic conditions and exploited the observation that intracellular accumulation of exogenously supplied [3H]cholesterol in the form of [3H]cholesteryl ester requires an intact PM-ER sterol transport pathway. Upc2-1 cells were mutagenized using a transposon library, incubated with [3H]cholesterol, and subjected to tritium suicide selection to isolate mutants with a decreased ability to accumulate [3H]cholesterol. Many of the mutants had defects in the expression and trafficking of Aus1 and Pdr11, PM-localized ABC transporters that are required for sterol uptake. Through characterization of one of the mutants, a new role was uncovered for the transcription factor Mot3 in controlling expression of Aus1 and Pdr11. A number of mutants had transposon insertions in the uncharacterized Ydr051c gene, which we now refer to as DET1 (decreased ergosterol transport). These mutants expressed Aus1 and Pdr11 normally but were severely defective in the ability to accumulate exogenously supplied cholesterol. The transport of newly synthesized sterols from the ER to the PM was also defective in det1Δ cells. These data indicate that the cytoplasmic protein encoded by DET1 is involved in intracellular sterol transport. PMID:19060182

  9. Tritium sources

    International Nuclear Information System (INIS)

    Glodic, S.; Boreli, F.

    1993-01-01

    Tritium is the only radioactive isotope of hydrogen. It directly follows the metabolism of water and it can be bound into genetic material, so it is very important to control levels of contamination. In order to define the state of contamination it is necessary to establish 'zero level', i.e. actual global inventory. The importance of tritium contamination monitoring increases with the development of fusion power installations. Different sources of tritium are analyzed and summarized in this paper. (author)

  10. Tritium storage

    International Nuclear Information System (INIS)

    Hircq, B.

    1989-01-01

    A general synthesis about tritium storage is achieved in this paper and a particular attention is given to practical application in the Fusion Technology Program. Tritium, storage under gaseous form and solid form are discussed (characteristics, advantages, disadvantages and equipments). The way of tritium storage is then discussed and a choice established as a function of a logic which takes into account the main working parameters

  11. Tritium in the food chain. Comparison of predicted and observed behaviour. A: Re-emission from soil and vegetation. B: Formation of organically bound tritium in grain of spring wheat

    International Nuclear Information System (INIS)

    Davis, P.; Strack, S.; Barry, P.

    1996-09-01

    This is the second Technical Report of the Special Radionuclides Tritium Working Group. It deals specifically with two major sources of model uncertainty concerning tritium re-emission from soils and vegetation, and the formation of organically bound tritium (OBT) in plant tissues under light and dark conditions which were identified during work undertaken for the first tritium Technical Report. Information obtained from two experiments was formulated into two specific Approach A type scenarios to investigate these aspects of tritium behaviour so that model predictions could be compared with actual observations and data. Data for HTO re-emission measured at two different field sampling sites in Canada were used as the basis for the model test exercise Scenario V2.1. One site was a wetland receiving groundwater discharge containing HTO from a nearby waste management area. The other site was a meadow which had been exposed to a gaseous discharge containing HTO vapour from a nearby CANDU nuclear power generating station. HTO re-emission was measured on several occasions while the prevailing wind carried the plume away from the site. For both sites, relevant site specific information was obtained including HTO concentrations in soil and vegetation and meteorological data for each of about 20 determinations each lasting for 30 to 45 minutes. Modelers were requested to predict net fluxes of water and HTO vapours at the two sites and specified times. Their predictions were compared with the actual water fluxes at the sites, which had been measured by both eddy-correlation and Bowen Ratio, and the HTO flux which had been obtained by measured concentration gradients and estimates of eddy diffusivities. Predicted water vapour fluxes agreed with those observed within 20% where the observed fluxes exceeded about 0.04 g m -2 s -1 . Lower fluxes were associated with meteorological conditions such as strong stability and light winds when assumptions underlying the equation are

  12. Tritium in the environment. Knowledge synthesis

    International Nuclear Information System (INIS)

    2009-01-01

    This report first presents the nuclear and physical-chemical properties of tritium and addresses the notions of bioaccumulation, bio-magnification and remanence. It describes and comments the natural and anthropic origins of tritium (natural production, quantities released in the environment in France by nuclear tests, nuclear plants, nuclear fuel processing plants, research centres). It describes how tritium is measured as a free element (sampling, liquid scintillation, proportional counting, enrichment method) or linked to organic matter (combustion, oxidation, helium-3-based measurement). It discusses tritium concentrations noticed in different parts of the environment (soils, continental waters, sea). It describes how tritium is transferred to ecosystems (transfer of atmospheric tritium to ground ecosystems, and to soft water ecosystems). It discusses existing models which describe the behaviour of tritium in ecosystems. It finally describes and comments toxic effects of tritium on living ground and aquatic organisms

  13. Tritium trick

    Science.gov (United States)

    Green, W. V.; Zukas, E. G.; Eash, D. T.

    1971-01-01

    Large controlled amounts of helium in uniform concentration in thick samples can be obtained through the radioactive decay of dissolved tritium gas to He3. The term, tritium trick, applies to the case when helium, added by this method, is used to simulate (n,alpha) production of helium in simulated hard flux radiation damage studies.

  14. Tritium in the food chain. Comparison of predicted and observed behaviour. A: Re-emission from soil and vegetation. B: Formation of organically bound tritium in grain of spring wheat

    Energy Technology Data Exchange (ETDEWEB)

    Davis, P. [AECL, Chalk River, ON (Canada); Strack, S. [Forschungszentrum Karlsruhe (Germany); Barry, P. [PJS Barry, (Canada)] [and others

    1996-09-01

    This is the second Technical Report of the Special Radionuclides Tritium Working Group. It deals specifically with two major sources of model uncertainty concerning tritium re-emission from soils and vegetation, and the formation of organically bound tritium (OBT) in plant tissues under light and dark conditions which were identified during work undertaken for the first tritium Technical Report. Information obtained from two experiments was formulated into two specific Approach A type scenarios to investigate these aspects of tritium behaviour so that model predictions could be compared with actual observations and data. Data for HTO re-emission measured at two different field sampling sites in Canada were used as the basis for the model test exercise Scenario V2.1. One site was a wetland receiving groundwater discharge containing HTO from a nearby waste management area. The other site was a meadow which had been exposed to a gaseous discharge containing HTO vapour from a nearby CANDU nuclear power generating station. HTO re-emission was measured on several occasions while the prevailing wind carried the plume away from the site. For both sites, relevant site specific information was obtained including HTO concentrations in soil and vegetation and meteorological data for each of about 20 determinations each lasting for 30 to 45 minutes. Modelers were requested to predict net fluxes of water and HTO vapours at the two sites and specified times. Their predictions were compared with the actual water fluxes at the sites, which had been measured by both eddy-correlation and Bowen Ratio, and the HTO flux which had been obtained by measured concentration gradients and estimates of eddy diffusivities. Predicted water vapour fluxes agreed with those observed within 20% where the observed fluxes exceeded about 0.04 g m{sup -2} s{sup -1}. Lower fluxes were associated with meteorological conditions such as strong stability and light winds when assumptions underlying the

  15. Examination of Transport Performance and Authenticity on Behavioural Intention

    Directory of Open Access Journals (Sweden)

    Bintang Handayani

    2015-12-01

    Full Text Available This study aims to scrutinise the transport performance and authenticity as one of the elements in tourism attributes in relation with behavioural intention. Utilising quantitative approach; data collected from survey of 384 overseas tourists were used to clarify the research proposition. The study suggests that transport performance may emerge as one of organic image elements for destination brand identity formation, influences cognitive image of overseas tourist but insignificant on tourist’s behavioural intention. In addition, future spectrum of the transport development in relation with authenticity indicates its importance for not damaging the destination’s overall profile.

  16. Environmental tritium

    International Nuclear Information System (INIS)

    Gans, I.

    1974-10-01

    The radioactive hydrogen isotope tritium can be found in all water occurrences. The concentration of natural tritium measured before 1954 amounts to 26 picocuries per liter in precipitation, 5 to 20 picocuries per liter in surface water, and 1 picocurie per liter in sea water. Since then, due to thermonuclear waepons tests in the atmosphere, considerably higher concentrations have been measured - 1963 the annual mean for precipitation went up to 10 4 picocuries per liter. Today in Middle Europe some hundred picocuries per liter are found in precipitation and surface water, less than 100 picocuries per liter in sea water, and in general less than 15 picocuries per liter in ground water. Artificial tritium today is applied in large scale in research and industry. It is of special importance as waste in the peaceful uses of nuclear energy. In the future, however, tritium emissions from nuclear power plants are less important than releases from reprocessing plants. Estimations show that the global environmental impact is small. For regions with a large density of nuclear power installations, radiation exposures of the order of magnitude of 10 mrem are predicted with pessimistic assumptions. More realistic assumptions lead to dose values of about 0.1 mrem caused by the influence of tritium. This is 80% of the dose caused by the release of radioactive material from nuclear power installations. (orig.) [de

  17. Tritium pellet injection sequences for TFTR

    International Nuclear Information System (INIS)

    Houlberg, W.A.; Milora, S.L.; Attenberger, S.E.; Singer, C.E.; Schmidt, G.L.

    1983-01-01

    Tritium pellet injection into neutral deuterium, beam heated deuterium plasmas in the Tokamak Fusion Test Reactor (TFTR) is shown to be an attractive means of (1) minimizing tritium use per tritium discharge and over a sequence of tritium discharges; (2) greatly reducing the tritium load in the walls, limiters, getters, and cryopanels; (3) maintaining or improving instantaneous neutron production (Q); (4) reducing or eliminating deuterium-tritium (D-T) neutron production in non-optimized discharges; and (5) generally adding flexibility to the experimental sequences leading to optimal Q operation. Transport analyses of both compression and full-bore TFTR plasmas are used to support the above observations and to provide the basis for a proposed eight-pellet gas gun injector for the 1986 tritium experiments

  18. Molecular transport behaviour of organic solvents through halloysite ...

    Indian Academy of Sciences (India)

    925–933. c Indian Academy of Sciences. Molecular transport behaviour of organic ... Micro and Nano Materials Laboratory, Department of Chemistry, Institute of Technical Education and Research,. Siksha 'O' Anusandhan ... of the performance of polymers in the environment of hazardous solvents, vapours and tempera-.

  19. Simulation of tritium behavior after intended tritium release in ventilated room

    International Nuclear Information System (INIS)

    Iwai, Yasunori; Hayashi, Takumi; Yamanishi, Toshihiko; Kobayashi, Kazuhiro; Nishi, Masataka

    2001-01-01

    At the Tritium Process Laboratory (TPL) at the Japan Atomic Energy Research Institute (JAERI), Caisson Assembly for Tritium Safety study (CATS) with 12 m 3 of large airtight vessel (Caisson) was fabricated for confirmation and enhancement of fusion reactor safety to estimate tritium behavior in the case where a tritium leak event should happen. One of the principal objectives of the present studies is the establishment of simulation method to predict the tritium behavior after the tritium leak event should happen in a ventilated room. The RNG model was found to be valid for eddy flow calculation in the 50 m 3 /h ventilated Caisson with acceptable engineering precision. The calculated initial and removal tritium concentration histories after intended tritium release were consistent with the experimental observations in the 50 m 3 /h ventilated Caisson. It is found that the flow near a wall plays an important role for the tritium transport in the ventilated room. On the other hand, tritium behavior intentionally released in the 3,000 m 3 of tritium handling room was investigated experimentally under a US-Japan collaboration. The tritium concentration history calculated with the same method was consistent with the experimental observations, which proves that the present developed method can be applied to the actual scale of tritium handling room. (author)

  20. Radiotoxicity of tritium in mammals

    International Nuclear Information System (INIS)

    Silini, G.; Metalli, P.; Vulpis, G.

    1972-12-01

    Basic data relative to tritium, its physicochemical behaviour in environment, its major sources of contamination and its metabolism through the mammalian organisms are reviewed. After considering the radiotoxicity of tritium particularly at the cellular and whole-body level the conclusion is drawn that the major uncertainties regard the fraction of tritium incorporated into the nuclei of some tissues. This fraction is eliminated very slowly and is capable of modifying the genetic structures of the nucleus. A more refined analysis of radiobiological phenomena and a better knowledge of the dose effect relationship should permit the extrapolation of the data to the low doses of tritium contamination. This extrapolation is of great interest in the field of public health for the elaboration of the relevant radioprotection standards

  1. Energy behaviour of neutrons generated by Witch-type distributed axi-symmetrical deuteron beams accelerated onto plane tritium targets

    International Nuclear Information System (INIS)

    Timus, D.M.; Bradley, D.A.; Timus, B.D.; Kalla, S.L.; Srivastava, H.M.

    2000-01-01

    This paper is an analytical study of the spatial dependency of the d-T neutron energy in the vicinity of a homogeneous tritium-occluded plane target. Close to the target, and along the path of incidence of axially symmetric deuteron beams, the transverse density of accelerated deuterons is assumed to be governed by a law approximated by the 'Witch' function. In particular circumstances, the elementary neutron emission process in non-dispersive media can be considered to be omni-directional (due consideration being paid to collision kinetics, depending upon mass and kinetic energy of particles involved in the nuclear collision, nuclear reaction energy, etc.). Consequently, analytical expressions can be considerably simplified. By applying the classical kinetic energy and momentum conservation laws to nuclear processes, a theoretical description is obtained, taking into account the exoergic character of d-T fusion reaction. A number of expressions for energetic prediction of the fast neutron field are proposed. The associated relations, involving elementary functions, can be investigated using a desk-top computer. Computationally tractable tools are of importance in the study of diverse situations such as induced reactions and activation analysis using 14 MeV neutron generators, investigations in health-physics, radiation dose measurements, nuclear medicine, damage effects, and simulation studies

  2. Tritium measurement and transport

    International Nuclear Information System (INIS)

    Rodrigo, L.; Miller, J.M.; Yin, D.

    1993-05-01

    The Jesse effect - the effect of impurities and intentionally added components on ionization in noble gases - is briefly described. Experiments to measure this effect in a specially constructed system with a 63 Ni beta-particle source are described. Results show that ionization chamber calibrations with helium carrier gas change rapidly with gaseous additions or impurities at low concentrations, and reach a plateau (approximately 50% calibration change) at 4000 ppm addition. Only small changes are seen with argon carrier gas. Implications of this effect in fusion blanket sweep-gas experiments are discussed. (author). 6 refs., 2 tabs., 5 figs

  3. The Chalk River Tritium Extraction Plant

    International Nuclear Information System (INIS)

    Holtslander, W.J.; Harrison, T.E.; Spagnolo, D.A.

    1990-01-01

    The Chalk River Tritium Extraction Plant for removal of tritium from heavy water is described. Tritium is present in the heavy water from research reactors in the form of DTO at a concentration in the range of 1-35 Ci/kg. It is removed by a combination of catalytic exchange to transfer the tritium from DTO to DT, followed by cryogenic distillation to separate and concentrate the tritium to T 2 . The tritium product is reacted with titanium and packaged for transportation and storage as titanium tritide. The plant processes heavy water at a rate of 25 kg/h and removes 80% of the tritium and 90% of the protium per pass. Catalytic exchange is carried out in the liquid phase using a proprietary wetproofed catalyst. The plant serves two roles in the Canadian fusion program: it produces pure tritium for use in fusion research and development, and it demonstrates on an industrial scale many of the tritium technologies that are common to the tritium systems in fusion reactors (author)

  4. Tritium handling in vacuum systems

    Energy Technology Data Exchange (ETDEWEB)

    Gill, J.T. [Monsanto Research Corp., Miamisburg, OH (United States). Mound Facility; Coffin, D.O. [Los Alamos National Lab., NM (United States)

    1986-10-01

    This report provides a course in Tritium handling in vacuum systems. Topics presented are: Properties of Tritium; Tritium compatibility of materials; Tritium-compatible vacuum equipment; and Tritium waste treatment.

  5. Tritium research activities in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Ki Jung, E-mail: kjjung@nfri.re.kr [National Fusion Research Institute, Yusung-gu, Daejeon 305-333 (Korea, Republic of); Yun, Sei-Hun, E-mail: shyun@nfri.re.kr [National Fusion Research Institute, Yusung-gu, Daejeon 305-333 (Korea, Republic of); Chang, Min Ho; Kang, Hyun-Goo; Chung, Dongyou; Cho, Seungyon; Lee, Hyeon Gon [National Fusion Research Institute, Yusung-gu, Daejeon 305-333 (Korea, Republic of); Chung, Hongsuk; Choi, Woo-Seok [Korea Atomic Energy Research Institute, Yusung-gu, Daejeon 305-353 (Korea, Republic of); Song, Kyu-Min; Moon, Chang-Bae [Korea Hydro & Nuclear Power Central Research Institute, Yusung-gu, Daejeon 305-343 (Korea, Republic of); Lee, Euy Soo [Dongguk University, Jung-gu, Seoul, 100-715 (Korea, Republic of); Cho, Jungho; Kim, Dong-Sun [Kongju National University, Cheonan, Chungnam, 330-717 (Korea, Republic of); Moon, Hung-Man [Daesung Industrial Gases Co., Ltd., Danwon-gu, Ansan-si, Gyeonggi-do, 425-090 (Korea, Republic of); Noh, Seung Jeong [Dankook University, Suji-gu, Yongin-si, Gyeonggi-do, 448-701 (Korea, Republic of); Ju, Hyunchul [Inha University, Nam-gu, Incheon, 402-751 (Korea, Republic of); Hong, Tae-Whan [Korea National University of Transportation, Chungju, Chungbuk, 380-702 (Korea, Republic of)

    2016-12-15

    Highlights: • NFRI, KAERI and KHNP CRI are major leading group for the ITER tritium SDS design; studying engineering, simulation of hydride bed, risk analysis (on safety, HAZOP), basic study, control logic & sequential operation, and others. KHNP has WTRF which gives favorable experiences for collaboration researchers. • Supplementary research partners: Five Universities (Dongguk University and POSTECH, Inha University, Dankook University, Korea National Transport University, and Kongju National University) and one industrial company (Daesung Industrial Gases Co., Ltd.); studying on basic and engineering, programming & simulation on the various topics for ITER tritium SDS, TEP, ISS, ADS, and etc. - Abstract: Major progress in tritium research in the Republic of Korea began when Korea became responsible for ITER tritium Storage and Delivery System (SDS) procurement package which is part of the ITER Fuel Cycle. To deliver the tritium SDS package, a variety of research institutes, universities and industry have respectively taken roles and responsibilities in developing technologies that have led to significant progress. This paper presents the current work and status of tritium related technological research and development (R&D) in Korea and introduces future R&D plans in the area of fuel cycle systems for fusion power generation.

  6. Application of tritium behavior simulation code (TBEHAVIOR) to an actual-scale tritium handling room

    International Nuclear Information System (INIS)

    Iwai, Yasunori; Hayashi, Takumi; Kobayashi, Kazuhiro; Yamanishi, Toshihiko

    2007-11-01

    It is essential from the viewpoint of fusion safety to confine and remove tritium in a room since tritium handling room is placed as 'final barrier' of fusion plant to prevent the environmental discharge of tritium. At the Tritium Process Laboratory (TPL) of Japan Atomic Energy Agency (JAEA), the application of our original three-dimensional TBEHAVIOR code to the tritium behavior in a room of 3000 m 3 was verified. The Renormalization Group Theory (RNG) model was selected as Low-Reynolds model for practical calculation time as well as to reasonable precision in evaluation of velocity from the engineering viewpoint. A series of evaluated results indicated that a flow adjacent to a wall surface plays an important role for tritium transport in a ventilated room. Evaluation of attenuating behavior is further important since the ventilation is normally stopped for the tritium confinement in the case of tritium leakage. We demonstrated that an attenuating behavior can also be evaluated well by the TBEHAVIOR code. Even an attenuating or stagnant flow of less than 10mm/s in a room mixed tritium concentration uniform promptly. The presence of apparatuses in a room did not generally affect tritium behavior. Although the effect of buoyancy was limited to the initial period after the leak, the spread of tritium was promoted by buoyancy. It led to the shortening of elapsed time until the concentration became uniform. (author)

  7. Magmatic tritium

    International Nuclear Information System (INIS)

    Goff, F.; Aams, A.I.; McMurtry, G.M.; Shevenell, L.; Pettit, D.R.; Stimac, J.A.; Werner, C.

    1997-01-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory. Detailed geochemical sampling of high-temperature fumaroles, background water, and fresh magmatic products from 14 active volcanoes reveal that they do not produce measurable amounts of tritium ( 3 H) of deep origin ( 2 O). On the other hand, all volcanoes produce mixtures of meteoric and magmatic fluids that contain measurable 3 H from the meteoric end-member. The results show that cold fusion is probably not a significant deep earth process but the samples and data have wide application to a host of other volcanological topics

  8. Tritium time series in precipitation of Rm. Valcea, Romania.

    Science.gov (United States)

    Varlam, Carmen; Duliu, Octavian G; Faurescu, Ionut; Vagner, Irina; Faurescu, Denisa

    2016-01-01

    Following tritium concentration records in precipitation for the period 1999-2013 and tritium concentration behaviour during this period for the Ramnicu Valcea (Rm. Valcea) location, the tritium level of individual precipitations of the late spring and summer for the 2009-2013 period was investigated. Despite good correlation between monthly mean tritium concentrations and monthly mean precipitations over the 15-year period of observations (Pearson coefficient 0.87), the individual precipitations had no linear correlation between the tritium concentration and the amount of precipitation.

  9. Tritium loss in molten flibe systems

    International Nuclear Information System (INIS)

    Longhurst, G.R.; Anderl, R.A.; Scott Willms, R.

    2000-01-01

    An emerging issue relative to beryllium technology in fusion involves tritium interactions with molten beryllium-bearing salts. Innovative designs for fusion reactors, both magnetic and inertially confined, feature the molten salt mixture 2LiF.BeF 2 , commonly called Flibe, as a tritium breeder and coolant. Tritium is bred in the Flibe as neutrons from the plasma are absorbed by Li atoms, which then transmute to tritium and helium. Transmutation of tritium from Be also occurs. Among the issues to be resolved for such coolant systems is the potential loss of tritium from the Flibe coolant to the walls of the system, particularly through heat exchanger tubes, and from there into secondary coolants or working fluids and the environment. Effectively removing tritium from Flibe in clean-up units is also important. In quiescent or low Reynolds number flow, tritium movement through Flibe is governed by diffusion. For Flibe in turbulent flow, as in heat exchanger tubes, transport is by turbulent mixing, and the same flow conditions and structural design features that maximize heat transfer to the heat exchanger walls will enhance the transport of tritium to those same surfaces. Analyses have been performed to estimate the fractional loss of tritium through heat exchanger tubes and release rates from Flibe droplets in vacuum disengagers in molten Flibe systems. The calculations suggest unacceptably large losses of tritium through heat exchanger tubes. The gravity of the implications of these estimates calls for experimental verification to determine if tritium losses through molten Flibe heat exchangers or other Flibe systems can really be so high and whether vacuum disengagers will really work. There is also a need for better information on evolution of tritium from Flibe droplets in a vacuum. Several experiments are presently being planned to address these issues and are discussed. These include experiments to induce tritium in Flibe using spontaneous fission neutrons

  10. Diurnal variations of tritium uptake by plants

    International Nuclear Information System (INIS)

    Hettinger, M.; Diabate, S.; Strack, S.

    1991-02-01

    The influence of the diurnal cycle is important for the behaviour of environmental tritium in the vegetation. A mathematical model has been used to calculate the deposition of tritium in plants as a function of diurnal variations of climatic parameters. The necessary physiological parameters (relationship of net photosynthesis and growth) were derived from growth experiments for tomatoes and maize. In chamber experiments, tomato and maize plants were exposed to tritium with natural diurnal variations of the climatic conditions. Within the range of standard deviations the measured concentrations of tritium in tissue free water of tomatoes correspond well to the estimated values. Furthermore, the incorporation into non-exchangeable organically bound tritium (OBT nx) can be sufficiently modelled and explained. There are deviations from the estimated concentrations in some parts of maize leaves. (orig.) [de

  11. Tritium control in helium-cooled blankets

    International Nuclear Information System (INIS)

    Wong, C.P.C.; Maya, I.; Kessel, C.; Roelant, D.; Schultz, K.R.

    1985-06-01

    As a part of the Blanket Comparison and Selection Study (BCSS), GA Technologies was responsible for the design of helium-cooled, solid- and liquid-metal breeder blankets. Conceptual blanket designs were developed, including the consideration of the generation, transport, and extraction of tritium. Evaluations were made of the inventory and leakage of tritium for helium-cooled Li 2 O and LiAlO 2 and liquid lithium breeder blankets for tokamak and tandem mirror reactors. To facilitate the evaluation, a solid breeder tritium code TRIT4 was developed. The results from this study indicate that tritium inventories and leakages are acceptable for the proposed helium-cooled blankets. An assumption made in the tritium leakage calculations was that tritium is released to the helium purge and coolant streams as T 2 and remains in that form. If oxidation to T 2 O is possible, significant reduction in the tritium leakage will be possible. We conclude that more experimental data on breeder material properties and tritium permeation behavior are needed. However, we are certain that an adequate number of different techniques are available to control the breeder tritium inventory and leakage to an acceptable level in helium-cooled solid- and lithium-breeder blankets

  12. Transfer and incorporation of tritium in mammals

    International Nuclear Information System (INIS)

    Hoek, J. van den; Juan, N.B.

    1979-01-01

    The metabolism of tritium in mammals has been studied in a number of laboratories which have participated in the IAEA Co-ordinated Research Programme on the Behaviour of Tritium in the Environment. The results of these studies are discussed and related to data obtained elsewhere. The animals studied are small laboratory and domestic animals. Tritium has been administered as THO, both in single and long-term dosing experiments, and also as organically bound tritium. The biological half-life of tritium in the body water pool has been determined in different species. The following values have been found: 1.1 days in mice; 13.2 days in kangaroo rats; 3.8 days in pigs; 4.1 days in lactating versus 8.3 in non-lactating goats and 3.1-4.0 days in lactating cows and steers. Much attention has been paid to the incorporation of tritium into organic constituents, both in the animal organism (organs, tissues) and in the secretions of the animal after continuous administration of tritium, mostly as THO. When compared with tritium levels in body water, and expressed as the ratio of specific activities, values of 0.25 and 0.40 have been found in mice liver and testis respectively. In cow's milk, these ratios vary from 0.30 for casein to 0.60 for lactose. The transfer of tritium into milk after continuous ingestion of THO by a lactating cow is about 1.50% of the daily ingested tritium per litre of milk. Some results of experiments, utilizing organically bound tritium, are also presented. (author)

  13. Tritium accountancy

    International Nuclear Information System (INIS)

    Avenhaus, R.; Spannagel, G.

    1995-01-01

    Conventional accountancy means that for a given material balance area and a given interval of time the tritium balance is established so that at the end of that interval of time the book inventory is compared with the measured inventory. In this way, an optimal effectiveness of accountancy is achieved. However, there are still further objectives of accountancy, namely the timely detection of anomalies as well as the localization of anomalies in a major system. It can be shown that each of these objectives can be optimized only at the expense of the others. Recently, Near-Real-Time Accountancy procedures have been studied; their methodological background as well as their merits will be discussed. (orig.)

  14. Magmatic tritium

    Energy Technology Data Exchange (ETDEWEB)

    Goff, F.; Aams, A.I. [Los Alamos National Lab., NM (United States); McMurtry, G.M. [Univ. of Hawaii, Honolulu, HI (United States); Shevenell, L. [Univ. of Nevada, Reno, NV (United States); Pettit, D.R. [National Aeronautics and Space Administration (United States); Stimac, J.A. [Union Geothermal Company (United States); Werner, C. [Pennsylvania State Univ., University Park, PA (United States)

    1997-07-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory. Detailed geochemical sampling of high-temperature fumaroles, background water, and fresh magmatic products from 14 active volcanoes reveal that they do not produce measurable amounts of tritium ({sup 3}H) of deep origin (<0.1 T.U. or <0.32 pCi/kg H{sub 2}O). On the other hand, all volcanoes produce mixtures of meteoric and magmatic fluids that contain measurable {sup 3}H from the meteoric end-member. The results show that cold fusion is probably not a significant deep earth process but the samples and data have wide application to a host of other volcanological topics.

  15. Tritium in the environment. The IRSN's opinion on key issues and on research and development perspectives

    International Nuclear Information System (INIS)

    2010-01-01

    This report states the opinion of the IRSN on issues related to the behaviour of tritium in the environment, and to the associated risks. This report is based on a set of studies and researches performed on this radionuclide. Thus, the authors address the status of knowledge on the evolution of tritium released by nuclear activities (measurement techniques), the risk of bioaccumulation of tritium by living organisms within ecosystems (behaviour of tritium in the atmosphere, in soils, in ground plants, in continental and sea aquatic media), and the knowledge of risks due to tritium absorbed by living organisms (dose assessment, knowledge of tritium harmful effects and relative biological effectiveness)

  16. Turkey Point tritium. Progress report

    International Nuclear Information System (INIS)

    Ostlund, H.G.; Dorsey, H.G.

    1976-01-01

    In 1972-73 the Florida Power and Light Company (FPL) began operation of two nuclear reactors at Turkey Point on lower Biscayne Bay. One radioactive by-product resulting from the operation of the nuclear reactors, tritium, provides a unique opportunity to study transport and exchange processes on a local scale. Since the isotope in the form of water is not removed from the liquid effluent, it is discharged to the cooling canal system. By studying its residence time in the canal and the pathways by which it leaves the canals, knowledge of evaporative process, groundwater movement, and bay exchange with the ocean can be obtained. Preliminary results obtained from measurement of tritium levels, both in the canal system and in the surrounding environment are discussed. Waters in lower Biscayne Bay and Card and Barnes Sounds receive only a small portion of the total tritium produced by the nuclear plant. The dominating tritium loss most likely is through evaporation from the canals. The capability of measuring extremely low HTO levels allows the determination of the evaporation rate experimentally by measuring the tritium levels of air after having passed over the canals

  17. Tritium Management Loop Design Status

    Energy Technology Data Exchange (ETDEWEB)

    Rader, Jordan D. [ORNL; Felde, David K. [ORNL; McFarlane, Joanna [ORNL; Greenwood, Michael Scott [ORNL; Qualls, A L. [ORNL; Calderoni, Pattrick [Idaho National Laboratory (INL)

    2017-12-01

    This report summarizes physical, chemical, and engineering analyses that have been done to support the development of a test loop to study tritium migration in 2LiF-BeF2 salts. The loop will operate under turbulent flow and a schematic of the apparatus has been used to develop a model in Mathcad to suggest flow parameters that should be targeted in loop operation. The introduction of tritium into the loop has been discussed as well as various means to capture or divert the tritium from egress through a test assembly. Permeation was calculated starting with a Modelica model for a transport through a nickel window into a vacuum, and modifying it for a FLiBe system with an argon sweep gas on the downstream side of the permeation interface. Results suggest that tritium removal with a simple tubular permeation device will occur readily. Although this system is idealized, it suggests that rapid measurement capability in the loop may be necessary to study and understand tritium removal from the system.

  18. Tritium experience in the Tokamak Fusion Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, C.H.; Blanchard, W.; Hosea, J.; Mueller, D.; Nagy, A. [Princeton Univ., NJ (United States). Princeton Plasma Physics Lab.; Brooks, J.N. [Argonne National Lab., IL (United States); Hogan, J. [Oak Ridge National Lab., TN (United States)

    1998-07-01

    Tritium management is a key enabling element in fusion technology. Tritium fuel was used in 3.5 years of successful deuterium-tritium (D-T) operations in the Tokamak Fusion Test Reactor (TFTR) at the Princeton Plasma Physics Laboratory. The D-T campaign enabled TFTR to explore the transport, alpha physics, and MHD stability of a reactor core. It also provided experience with tritium retention and removal that highlighted the importance of these issues in future D-T machines. In this paper, the authors summarize the tritium retention and removal experience in TFTR and its implications for future reactors.

  19. Tritium experience in the Tokamak Fusion Test Reactor

    International Nuclear Information System (INIS)

    Skinner, C.H.; Blanchard, W.; Hosea, J.; Mueller, D.; Nagy, A.; Hogan, J.

    1998-01-01

    Tritium management is a key enabling element in fusion technology. Tritium fuel was used in 3.5 years of successful deuterium-tritium (D-T) operations in the Tokamak Fusion Test Reactor (TFTR) at the Princeton Plasma Physics Laboratory. The D-T campaign enabled TFTR to explore the transport, alpha physics, and MHD stability of a reactor core. It also provided experience with tritium retention and removal that highlighted the importance of these issues in future D-T machines. In this paper, the authors summarize the tritium retention and removal experience in TFTR and its implications for future reactors

  20. Cycling in multimodal transport behaviours: Exploring modality styles in the Danish population

    DEFF Research Database (Denmark)

    Olafsson, Anton Stahl; Nielsen, Thomas Alexander Sick; Carstensen, Trine Agervig

    2016-01-01

    or 'modality styles' are identified: 'education transport'; 'public-based transport'; 'limited transport'; 'bicycle-based transport'; and 'car-based transport'. Travel behaviour is predominantly multimodal with few unimodal car-drivers being identified. Substantial cycling takes place in all modality styles......Multimodality is important for achieving less car dependent lifestyles and more sustainable transport behaviours. It is widely recognised that cycling plays a prominent role in sustainable transport. However, research has largely focused on cycling substituting motorised transport. This study...... explores how cycling forms part of multimodal transport behaviour based on survey data on transport modes and travel purposes and the weekly frequency of out-of-home activities and travel mode use in a representative sample of adult Danes (n = 1957). The following five distinct multimodal travel segments...

  1. Tritium activities in Canada

    International Nuclear Information System (INIS)

    Gierszewski, P.

    1995-01-01

    Canadian tritium activites comprise three major interests: utilites, light manufacturers, and fusion. There are 21 operating CANDU reactors in Canada; 19 with Ontario Hydro and one each with Hydro Quebec and New Brunswick Power. There are two light manufacturers, two primary tritium research facilities (at AECL Chalk River and Ontario Hydro Technologies), and a number of industry and universities involved in design, construction, and general support of the other tritium activities. The largest tritum program is in support of the CANDU reactors, which generate tritium in the heavy water as a by-product of normal operation. Currently, there are about 12 kg of tritium locked up in the heavy water coolant and moderator of these reactors. The fusion work is complementary to the light manufacturing, and is concerned with tritium handling for the ITER program. This included design, development and application of technologies related to Isotope Separation, tritium handling, (tritiated) gas separation, tritium-materials interaction, and plasma fueling

  2. The Tritium White Paper

    International Nuclear Information System (INIS)

    2009-01-01

    This publication proposes a synthesis of the activities of two work-groups between May 2008 and April 2010. It reports the ASN's (the French Agency for Nuclear Safety) point of view, describes its activities and actions, and gives some recommendations. It gives a large and detailed overview of the knowledge status on tritium: tritium source inventory, tritium origin, management processes, capture techniques, reduction, tritium metrology, impact on the environment, impacts on human beings

  3. Tritium in the Channel

    International Nuclear Information System (INIS)

    Masson, M.; Fievet, B.; Bailly-Du-Bois, P.; Olivier, A.; Tenailleau, L.

    2009-01-01

    After having recalled that sea waters entering the Channel exhibit a natural concentration of tritium, the authors outline that spent nuclear fuel reprocessing plants are now the main sources of tritium for marine ecosystems as some oceanographic campaigns showed it. If data about the presence of tritium in water are numerous, data concerning the presence of tritiated water and of organically bound tritium in organisms are much less frequent. However, some surveys have been performed along the Channel French coasts

  4. TFTR tritium handling concepts

    International Nuclear Information System (INIS)

    Garber, H.J.

    1976-01-01

    The Tokamak Fusion Test Reactor, to be located on the Princeton Forrestal Campus, is expected to operate with 1 to 2.5 MA tritium--deuterium plasmas, with the pulses involving injection of 50 to 150 Ci (5 to 16 mg) of tritium. Attainment of fusion conditions is based on generation of an approximately 1 keV tritium plasma by ohmic heating and conversion to a moderately hot tritium--deuterium ion plasma by injection of a ''preheating'' deuterium neutral beam (40 to 80 keV), followed by injection of a ''reacting'' beam of high energy neutral deuterium (120 to 150 keV). Additionally, compressions accompany the beam injections. Environmental, safety and cost considerations led to the decision to limit the amount of tritium gas on-site to that required for an experiment, maintaining all other tritium in ''solidified'' form. The form of the tritium supply is as uranium tritide, while the spent tritium and other hydrogen isotopes are getter-trapped by zirconium--aluminum alloy. The issues treated include: (1) design concepts for the tritium generator and its purification, dispensing, replenishment, containment, and containment--cleanup systems; (2) features of the spent plasma trapping system, particularly the regenerable absorption cartridges, their integration into the vacuum system, and the handling of non-getterables; (3) tritium permeation through the equipment and the anticipated releases to the environment; (4) overview of the tritium related ventilation systems; and (5) design bases for the facility's tritium clean-up systems

  5. Surface tritium contamination studies

    International Nuclear Information System (INIS)

    Sienkiewicz, C.J.

    1986-01-01

    Glovebox wipe surveys were conducted to correlate surface tritium contamination with atmospheric tritium levels. Surface contamination was examined as a function of tritium concentration and limited to the HT/T 2 form. The previously predicted relationship between atmospheric HTO concentration and cleanup times was examined in order to predict a model for atmospheric detritiation of stainless steel enclosures. 2 figures, 2 tables

  6. Review of tritium behavior in HTGR systems

    International Nuclear Information System (INIS)

    Gainey, B.W.

    1976-01-01

    The available experimental evidence from laboratory and reactor studies pertaining to tritium production, capture, release, and transport within an HTGR leading to release to the environment is reviewed. Possible mechanisms for release, capture, and transport are considered and a simple model was used to calculate the expected tritium release from HTGRs. Comparison with Federal regulations governing tritium release confirm that expected HTGR releases will be well within the allowable release limits. Releases from HTGRs are expected to be somewhat less than from LWRs based on the published LWR operating data. Areas of research deserving further study are defined but it is concluded that a tritium surveillance at Fort St. Vrain is the most immediate need

  7. Measurement of Tritium Surface Distribution on TFTR Bumper Limiter Tiles

    International Nuclear Information System (INIS)

    Sugiyama, K.; Tanabe, T.; Skinner, C.H.; Gentile, C.A.

    2004-01-01

    The tritium surface distribution on graphite tiles used in the Tokamak Fusion Test Reactor (TFTR) bumper limiter and exposed to TFTR deuterium-tritium (D-T) discharges from 1993 to 1997 was measured by the Tritium Imaging Plate Technique (TIPT). The TFTR bumper limiter shows both re-/co-deposition and erosion. The tritium images for all tiles measured are strongly correlated with erosion and deposition patterns, and long-term tritium retention was found in the re-/co-depositions and flakes. The CFC tiles located at erosion dominated areas clearly showed their woven structure in their tritium images owing to different erosion yields between fibers and matrix. Significantly high tritium retention was observed on all sides of the erosion tiles, indicating carbon transport via repetition of local erosion/deposition cycles

  8. A metabolic derivation of tritium transfer factors in animal products

    International Nuclear Information System (INIS)

    Galeriu, D.; Melintescu, A.; Crout, N. M. J.; Bersford, N. A.; Peterson, S. R.; Hess, M. van

    2001-01-01

    Tritium is a potentially important environmental contaminant arising from the nuclear industry. Because tritium is an isotope of hydrogen, its behaviour in the environment is controlled by the behaviour of hydrogen. Chronic releases of tritium to the atmosphere, in particular, will result in tritium-to-hydrogen (T/H) ratios in plants and animals that are more or less in equilibrium with T/H ratios in the air moisture. Tritium is thus a potentially important contaminant of plant and animal food products. The transfer of tritium from air moisture to plants is quite well understood. In contrast, although a number of regulatory agencies have published transfer coefficient values for diet tritium transfer for a limited number of animal products, a fresh evaluation of these transfers needs to be made In this paper we present an approach for the derivation of tritium transfer coefficients which is based on the metabolism of hydrogen in animals in conjunction with experimental data on tritium transfer. The derived transfer coefficients separately account for transfer to and from free (i.e. water) and organically bound tritium. The predicted transfer coefficients are compared to available data independent of model development. Agreement is good, with the exception of the transfer coefficient for transfer from tritiated water to organically bound tritium in ruminants, which may be attributable to the particular characteristics of ruminant digestion. We show that transfer coefficients will vary in response to the metabolic status of an animal (e.g. stage of lactation, digestibility of diet, etc.) and that the use of a single transfer coefficient from diet to animal product is not appropriate for tritium. It is possible to derive concentration ratio values which relate the concentration of tritiated water and organically bound tritium in an animal product to the corresponding concentrations in the animals diet. These concentration ratios are shown to be less subject to

  9. Tritium conference days

    International Nuclear Information System (INIS)

    Garnier-Laplace, J.; Lebaron-Jacobs, L.; Sene, M.; Devin, P.; Chretien, V.; Le Guen, B.; Guetat, Ph.; Baglan, N.; Ansoborlo, E.; Boyer, C.; Masson, M.; Bailly-Du-Bois, P.; Jenkinson, St.; Wakeford, R.; Saintigny, Y.; Romeo, P.H.; Thompson, P.; Leterq, D.; Chastagner, F.; Cortes, P.; Philippe, M.; Paquet, F.; Fournier, M.

    2009-01-01

    This document gathers the slides of the available presentations given during this conference day. Twenty presentations out of 21 are assembled in the document and deal with: 1 - tritium in the environment (J. Garnier-Laplace); 2 - status of knowledge about tritium impact on health (L. Lebaron-Jacobs); 3 - tritium, discrete but present everywhere (M. Sene); 4 - management of tritium effluents from Areva NC La Hague site - related impact and monitoring (P. Devin); 5 - tritium effluents and impact in the vicinity of EDF's power plants (V. Chretien and B. Le Guen); 6 - contribution of CEA-Valduc centre monitoring to the knowledge of atmospheric tritiated water transfers to the different compartments of the environment (P. Guetat); 7 - tritium analysis in environment samples: constraints and means (N. Baglan); 8 - organically-linked tritium: the analyst view (E. Ansoborlo); 9 - study of tritium transfers to plants via OBT/HTO air and OBT/HTO free (C. Boyer); 10 - tritium in the British Channel (M. Masson and P. Bailly-Du-Bois); 11 - tritium in British coastal waters (S. Jenkinson); 12 - recent results from epidemiology (R. Wakeford); 13 - effects of tritiated thymidine on hematopoietic stem cells (P.H. Romeo); 14 - tritium management issue in Canada: the point of view from authorities (P. Thompson); 15 - experience feedback of the detritiation process of Valduc centre (D. Leterq); 16 - difficulties linked with tritiated wastes confinement (F. Chastagner); 17 - optimisation of tritium management in the ITER project (P. Cortes); 18 - elements of thought about the management of tritium generated by nuclear facilities (M. Philippe); 19 - CIPR's position about the calculation of doses and risks linked with tritium exposure (F. Paquet); 20 - tritium think tanks (M. Fournier). (J.S.)

  10. Environmental aspects of tritium

    International Nuclear Information System (INIS)

    Quisenberry, D.R.

    1979-01-01

    The potential radiological implications of environmental tritium releases must be determined in order to develop a programme for dealing with the tritium inventory predicted for the nuclear power industry which, though still in its infancy, produces tritium in megacurie quantities annually. Should the development of fusion power generation become a reality, it will create a potential source for large releases of tritium, much of it in the gaseous state. At present about 90% of the tritium produced enters the environment through gaseous and liquid effluents and is deposited in the hydrosphere as tritiated water. Tritium can be assimilated by plants and animals and organically bound, regardless of the exposure pathway. However, there appears to be no concentration factor relative to hydrogen at any level of food chains analysed to date. The body burden, for man, is dependent on the exposure pathway and tissue-bound fractions are primarily the result of organically bound tritium in food. (author)

  11. Tritium pellet injector results

    International Nuclear Information System (INIS)

    Fisher, P.W.; Bauer, M.L.; Baylor, L.R.; Deleanu, L.E.; Fehling, D.T.; Milora, S.L.; Whitson, J.C.

    1988-01-01

    Injection of solid tritium pellets is considered to be the most promising way of fueling fusion reactors. The Tritium Proof-of- Principle (TPOP) experiment has demonstrated the feasibility of forming and accelerating tritium pellets. This injector is based on the pneumatic pipe-gun concept, in which pellets are formed in situ in the barrel and accelerated with high-pressure gas. This injector is ideal for tritium service because there are no moving parts inside the gun and because no excess tritium is required in the pellet production process. Removal of 3 He from tritium to prevent blocking of the cryopumping action by the noncondensible gas has been demonstrated with a cryogenic separator. Pellet velocities of 1280 m/s have been achieved for 4-mm-diam by 4-mm-long cylindrical tritium pellets with hydrogen propellant at 6.96 MPa (1000 psi). 10 refs., 10 figs

  12. Elemental tritium deposition and conversion in the terrestrial environment

    International Nuclear Information System (INIS)

    Dunstall, T.G.; Ogram, G.L.; Spencer, F.S.

    1985-01-01

    Studies were undertaken to determine the deposition and conversion of atmospheric elemental tritium in soils and vegetation. In the field tritium deposition velocities ranged between 0.007 and 0.07 cm s -1 during the summer and autumn and were less than 0.0005 cm s -1 during the winter. Deposition velocity was found to depend significantly on soil water content, total pore space and organic content in controlled laboratory experiments. In contrast to soils, exposure of vegetation to atmospheric elemental tritium resulted in negligible uptake and conversion in foliage. These studies are of significance to the assessment of behaviour and impact of elemental tritium releases

  13. Analysis of vadose zone tritium transport from an underground storage tank release using numerical modeling and geostatistics

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K.H.

    1997-09-01

    Numerical and geostatistical analyses show that the artificial smoothing effect of kriging removes high permeability flow paths from hydrogeologic data sets, reducing simulated contaminant transport rates in heterogeneous vadose zone systems. therefore, kriging alone is not recommended for estimating the spatial distribution of soil hydraulic properties for contaminant transport analysis at vadose zone sites. Vadose zone transport if modeled more effectively by combining kriging with stochastic simulation to better represent the high degree of spatial variability usually found in the hydraulic properties of field soils. However, kriging is a viable technique for estimating the initial mass distribution of contaminants in the subsurface.

  14. Issues Associated with Tritium Legacy Materials

    International Nuclear Information System (INIS)

    Mills, Michael

    2008-01-01

    This paper highlights some of the issues associated with the treatment of legacy materials linked to research into tritium over many years and also of materials used to contain or store tritium. The aim of the work is to recover tritium where practicable, and to leave the residual materials passively safe, either for disposal or for continued storage. A number of materials are currently stored at AWE which either contain tritium or have been used in tritium processing. It is essential that these materials are characterised such that a strategy may be developed for their safe stewardship, and ultimately for their treatment and disposal. Treatment processes for such materials are determined by the application of best practicable means (BPM) studies in accordance with the requirements of the Environment Agency of England and Wales. Clearly, it is necessary to understand the objectives of legacy material treatment / processing and the technical options available before a definitive BPM study is implemented. The majority of tritium legacy materials with which we are concerned originate from the decommissioning of a facility that was operational from the late 1950's through to the late 1990's when, on post-operative clear-out (POCO), the entire removable and transportable tritium inventory was moved to new, purpose built facilities. One of the principle tasks to be undertaken in the new facilities is the treatment of the legacy materials to recover tritium wherever practicable, and render the residual materials passively safe for disposal or continued storage. Where tritium recovery was not reasonably or technically feasible, then a means to assure continued safe storage was to be devised and implemented. The legacy materials are in the following forms: - Uranium beds which may or may not contain adsorbed tritium gas; - Tritium gas stored in containers; - Tritide targets for neutron generation; - Tritides of a broad spectrum of metals manufactured for research / long

  15. Tritium sampling and measurement

    International Nuclear Information System (INIS)

    Wood, M.J.; McElroy, R.G.; Surette, R.A.; Brown, R.M.

    1993-01-01

    Current methods for sampling and measuring tritium are described. Although the basic techniques have not changed significantly over the last 10 y, there have been several notable improvements in tritium measurement instrumentation. The design and quality of commercial ion-chamber-based and gas-flow-proportional-counter-based tritium monitors for tritium-in-air have improved, an indirect result of fusion-related research in the 1980s. For tritium-in-water analysis, commercial low-level liquid scintillation spectrometers capable of detecting tritium-in-water concentrations as low as 0.65 Bq L-1 for counting times of 500 min are available. The most sensitive method for tritium-in-water analysis is still 3He mass spectrometry. Concentrations as low as 0.35 mBq L-1 can be detected with current equipment. Passive tritium-oxide-in-air samplers are now being used for workplace monitoring and even in some environmental sampling applications. The reliability, convenience, and low cost of passive tritium-oxide-in-air samplers make them attractive options for many monitoring applications. Airflow proportional counters currently under development look promising for measuring tritium-in-air in the presence of high gamma and/or noble gas backgrounds. However, these detectors are currently limited by their poor performance in humidities over 30%. 133 refs

  16. Tritium waste management on the La Hague AREVA NC site: associated impact and monitoring

    International Nuclear Information System (INIS)

    Devin, P.; Deguette, H.

    2009-01-01

    The authors propose an analysis of tritium behaviour in the nuclear fuel processed in the AREVA NC plant in La Hague, of its presence in the plant and in its wastes, and of the impact of these wastes and the tritium monitoring in the environment. First, they present the AREVA NC plant and evoke the legal context concerning the waste management. They report and discuss the analysis of the presence and behaviour of tritium in irradiated fuel, of its behaviour during spent fuel processing, the evolution of tritium releases (legal limitations, evolutions since 1992), of measurement of activity in effluents, and discuss a study of possible reductions of tritium releases by La Hague plants (mainly in sea waters). They also report the computational assessment of the dosimetric impact of tritium on neighbouring population. They describe how the presence of tritium in the environment is monitored within the annual radioactivity monitoring programme

  17. Confinement and Tritium Stripping Systems for APT Tritium Processing

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, R.H. [Westinghouse Savannah River Company, AIKEN, SC (United States); Heung, L.K.

    1997-10-20

    This report identifies functions and requirements for the tritium process confinement and clean-up system (PCCS) and provides supporting technical information for the selection and design of tritium confinement, clean-up (stripping) and recovery technologies for new tritium processing facilities in the Accelerator for the Production of Tritium (APT). The results of a survey of tritium confinement and clean-up systems for large-scale tritium handling facilities and recommendations for the APT are also presented.

  18. Environmental tritium in trees

    International Nuclear Information System (INIS)

    Brown, R.M.

    1979-01-01

    The distribution of environmental tritium in the free water and organically bound hydrogen of trees growing in the vicinity of the Chalk River Nuclear Laboratories (CRNL) has been studied. The regional dispersal of HTO in the atmosphere has been observed by surveying the tritium content of leaf moisture. Measurement of the distribution of organically bound tritium in the wood of tree ring sequences has given information on past concentrations of HTO taken up by trees growing in the CRNL Liquid Waste Disposal Area. For samples at background environmental levels, cellulose separation and analysis was done. The pattern of bomb tritium in precipitation of 1955-68 was observed to be preserved in the organically bound tritium of a tree ring sequence. Reactor tritium was discernible in a tree growing at a distance of 10 km from CRNL. These techniques provide convenient means of monitoring dispersal of HTO from nuclear facilities. (author)

  19. NNSA TRITIUM SUPPLY CHAIN

    Energy Technology Data Exchange (ETDEWEB)

    Wyrick, Steven [Savannah River National Laboratory, Aiken, SC, USA; Cordaro, Joseph [Savannah River National Laboratory, Aiken, SC, USA; Founds, Nanette [National Nuclear Security Administration, Albuquerque, NM, USA; Chambellan, Curtis [National Nuclear Security Administration, Albuquerque, NM, USA

    2013-08-21

    Savannah River Site plays a critical role in the Tritium Production Supply Chain for the National Nuclear Security Administration (NNSA). The entire process includes: • Production of Tritium Producing Burnable Absorber Rods (TPBARs) at the Westinghouse WesDyne Nuclear Fuels Plant in Columbia, South Carolina • Production of unobligated Low Enriched Uranium (LEU) at the United States Enrichment Corporation (USEC) in Portsmouth, Ohio • Irradiation of TPBARs with the LEU at the Tennessee Valley Authority (TVA) Watts Bar Reactor • Extraction of tritium from the irradiated TPBARs at the Tritium Extraction Facility (TEF) at Savannah River Site • Processing the tritium at the Savannah River Site, which includes removal of nonhydrogen species and separation of the hydrogen isotopes of protium, deuterium and tritium.

  20. High-pressure tritium

    International Nuclear Information System (INIS)

    Coffin, D.O.

    1976-01-01

    Some solutions to problems of compressing and containing tritium gas to 200 MPa at 700 0 K are discussed. The principal emphasis is on commercial compressors and high-pressure equipment that can be easily modified by the researcher for safe use with tritium. Experience with metal bellows and diaphragm compressors has been favorable. Selection of materials, fittings, and gauges for high-pressure tritium work is also reviewed briefly

  1. Tritium in metals

    International Nuclear Information System (INIS)

    Schober, T.

    1990-01-01

    In this Chapter a review is given of some of the important features of metal tritides as opposed to hydrides and deuterides. After an introduction to the topics of tritium and tritium in metals information will be presented on a variety of metal-tritium systems. Of main interest here are the differences from the classic hydrogen behavior; the so called isotope effect. A second important topic is that of aging effects produced by the accumulation of 3 He in the samples. (orig.)

  2. Tritium and helium-3 in metals

    International Nuclear Information System (INIS)

    Lasser, R.

    1989-01-01

    The book surveys recent results on the behaviour of tritium and its decay product helium-3 metals. In contrast to many earlier books which discuss the properties of the stable hydrogen isotopes without mentioning tritium, this book reviews mainly the results on tritium in metals. Due to the difficulties in preparing metal tritide samples, very important quantities such as diffusivity, superconductivity, solubility, etc. have only been determined very recently. The book not only presents the measured tritium data, but also the isotopic dependency of the different physical properties by comparing H, D and T results. A chapter is devoted to helium-3 in metals. Aspects such as helium release, generation of helium bubbles, swelling, and change of the lattice parameter upon aging are discussed. The book provides the reader with up-to-date information and deep insight into the behaviour of H, D, T and He-3 in metals. Further important topics such a tritium production, its risks, handling and discharge to the environment are also addressed

  3. A neutron poison tritium breeding controller applied to a water cooled fusion reactor model

    International Nuclear Information System (INIS)

    Morgan, L.W.G.; Packer, L.W.

    2014-01-01

    the water coolant of a stratified blanket model, depending on the difference between the required tritium excess inventory and the measured tritium excess inventory. The compounds effectively reduce the amount of low energy neutrons available to react with lithium compounds, thus reducing the tritium breeding ratio. This controller reduces the amount of tritium being produced at the start of the reactor's lifetime and increases the rate of tritium production towards the end of its lifetime. Thus, a relatively stable tritium production level may be maintained, allowing the control system to minimize the stored tritium with obvious safety benefits. The FATI code (Fusion Activation and Transport Interface) will be used to perform the tritium breeding and controller calculations

  4. Incorporation of tritium in milk lipids after feeding organically bound tritium to cows

    International Nuclear Information System (INIS)

    Rochalska, M.; Hoek, J. van den

    1982-01-01

    Hay labelled with organically bound tritium was given to two cows for a period of 26 to 28 days. During hay feeding and at different times thereafter, lipids (fatty acids, cholesterol, glycerol, choline phospholipids, other phospholipids, flycolipids and gangliosides) were isolated from milk fat, and their total and specific activities were determined. During tritium administration, fatty acids and cholesterol contained the highest total activity, but the specific activity was highest in cholesterol and choline phospholipids. Activity decreased most rapidly for fatty acids and cholesterol, so that at 56 and 182 days after termination of 3 H feedings, phospholipids and glycolipids made an important contribution to lipid activity in milk. Regression analysis of the values for tritium activity in milk fat samples after stopping tritium administration, showed that three components with different half lives could be distinguished. The differences in metabolic behaviour of the various lipids in milk fat are mainly concerned with their relative participation in these components. (author)

  5. A model for global cycling of tritium

    International Nuclear Information System (INIS)

    Killough, G.G.; Kocher, D.C.

    1988-01-01

    Dynamic compartment models are widely used to describe global cycling of radionuclides for purposes of dose estimation. In this paper, we present a new global tritium model that reproduces environmental time-series data on concentrations in precipitation, ocean surface waters, and surface fresh waters in the northern hemisphere, concentrations of atmospheric tritium in the soutehrn hemisphere, and the latitude dependence of tritium in both hemispheres. Named TRICYCLE for Tritium CYCLE, the model is based on the global hydrologic cycle and includes hemisphereic stratospheric compartments, disaggregation of the troposphere and ocean surface waters into eight latitudezones, consideration of the different concentrations of atmospheric tritium over land and over the ocean, and a diffusive model for transport in the ocean. TRICYCLE reproduces the environmental data if we assume that about 50% of the tritium from atmospheric weapons testing was injected directly into the northern stratosphere as HTO. The models latitudinal disaggregation permits taking into account the distribution of population. For a unfiormaly distributed release of HTO into the worldwide troposphere, TRICYCLE predicts a collective dose commitment to the world population that exceeds the corresponding prediction by the NCRP model by about a factor of 3. 11 refs., 5 figs., 1 tab

  6. Radionuclide Basics: Tritium

    Science.gov (United States)

    Tritium is a hydrogen atom that has two neutrons in the nucleus and one proton. It is radioactive and behaves like other forms of hydrogen in the environment. Tritium is produced naturally in the upper atmosphere and as a byproduct of nuclear fission.

  7. Protection against tritium radiations

    International Nuclear Information System (INIS)

    Bal, Georges

    1964-05-01

    This report presents the main characteristics of tritium, describes how it is produced as a natural or as an artificial radio-element. It outlines the hazards related to this material, presents how materials and tools are contaminated and decontaminated. It addresses the issue of permissible maximum limits: factors of assessment of the risk induced by tritium, maximum permissible activity in body water, maximum permissible concentrations in the atmosphere. It describes the measurement of tritium activity: generalities, measurement of gas activity and of tritiated water steam, tritium-induced ionisation in an ionisation chamber, measurement systems using ionisation chambers, discontinuous detection of tritium-containing water in the air, detection of surface contamination [fr

  8. Current understanding of organically bound tritium (OBT) in the environment.

    Science.gov (United States)

    Kim, S B; Baglan, N; Davis, P A

    2013-12-01

    It has become increasingly recognized that organically bound tritium (OBT) is the more significant tritium fraction with respect to understanding tritium behaviour in the environment. There are many different terms associated with OBT; such as total OBT, exchangeable OBT, non-exchangeable OBT, soluble OBT, insoluble OBT, tritiated organics, and buried tritium, etc. A simple classification is required to clarify understanding within the tritium research community. Unlike for tritiated water (HTO), the environmental quantification and behaviour of OBT are not well known. Tritiated water cannot bio-accumulate in the environment. However, it is not clear whether or not this is the case for OBT. Even though OBT can be detected in terrestrial biological materials, aquatic biological materials and soil samples, its behaviour is still in question. In order to evaluate the radiation dose from OBT accurately, further study will be required to understand OBT measurements and determine OBT fate in the environment. The relationship between OBT speciation and the OBT/HTO ratio in environmental samples will be useful in this regard, providing information on the previous tritium exposure conditions in the environment and the current tritium dynamics. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  9. Tritium fuel cycle modeling and tritium breeding analysis for CFETR

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hongli; Pan, Lei; Lv, Zhongliang; Li, Wei; Zeng, Qin, E-mail: zengqin@ustc.edu.cn

    2016-05-15

    Highlights: • A modified tritium fuel cycle model with more detailed subsystems was developed. • The mean residence time method applied to tritium fuel cycle calculation was updated. • Tritium fuel cycle analysis for CFETR was carried out. - Abstract: Attaining tritium self-sufficiency is a critical goal for fusion reactor operated on the D–T fuel cycle. The tritium fuel cycle models were developed to describe the characteristic parameters of the various elements of the tritium cycle as a tool for evaluating the tritium breeding requirements. In this paper, a modified tritium fuel cycle model with more detailed subsystems and an updated mean residence time calculation method was developed based on ITER tritium model. The tritium inventory in fueling system and in plasma, supposed to be important for part of the initial startup tritium inventory, was considered in the updated mean residence time method. Based on the model, the tritium fuel cycle analysis of CFETR (Chinese Fusion Engineering Testing Reactor) was carried out. The most important two parameters, the minimum initial startup tritium inventory (I{sub m}) and the minimum tritium breeding ratio (TBR{sub req}) were calculated. The tritium inventories in steady state and tritium release of subsystems were obtained.

  10. FDMH - The tritium model in RODOS

    International Nuclear Information System (INIS)

    Galeriu, D.; Mateescu, G.; Melintescu, A.; Turcanu, C.; Raskob, W.

    2000-01-01

    Under the auspices of its RTD (Research and Technological Development) Framework Programmes, the European Commission has supported the development of the RODOS (Real-time On-line DecisiOn Support) system for off-site emergency management. The project started in 1989 focusing on PWR/LWR type accidents and using experience from the Chernobyl accident. In 1996 it was realised that tritium should be included in the list of radionuclides, as large tritium sources exist in Europe and to allow a potential expansion of the RODOS system for application on future fusion reactor accidents. The National Institute for Physics and Nuclear Engineering (IFIN-HH) in Romania - in close co-operation with the Research Centre Karlsruhe (FZK) - was charged to develop the tritium module, based on previous experience in environmental tritium modelling and the operation of CANDU reactor-based NPP in Romania (with potential tritium accidents). Tritium, being an isotope of hydrogen, is incorporated immediately in the life cycle and its transport into the biosphere differs considerably from other radionuclides treated by the RODOS system. Concentrations in the individual compartments may change very rapidly (hours) under varying environmental conditions and conversion to organic forms by biochemical and metabolic processes takes place in plants and animals. Consequently, the tritium code in RODOS was developed as a separate module and harmonisation in data sets and interfaces with other food chain modules integrated in RODOS was ensured. Presently, the tritium module - FDMH- is integrated and documented in the RODOS system, delivering time dependent tritium concentration (as tritiated water or organically bound tritium) in plant and animal products, inhalation dose and ingestion dose for various groups of population, after an accident emitting tritiated water and for up to 2520 locations around the source. FDMH incorporates many improved techniques in radiological assessment and makes

  11. Investigation of tritium transfer to plants via the OBT/HTO and OBT/TFWT ratios

    International Nuclear Information System (INIS)

    Boyer, C.; Guetat, P.; Vichot, L.; Losset, Y.; Boyer, C.; Fromm, M.; Mavon, C.; Boyer, C.; Tatin-Froux, F.; Badot, P.M.

    2009-01-01

    After having recalled some concepts used to distinguish the various forms of water present in plants, and the reactions in presence of tritium, the authors discuss the biochemical behaviour of tritium. Then, they briefly report a literature survey and, for different plants and crops, indicate the values of the OBT/HTO (organically bound tritium/tritiated water) and OBT/TFWT (organically bound tritium/tissue free water tritium) ratios. They also report experimental studies performed by exposures of lettuces at the vicinity of a nuclear installation

  12. Molecular transport behaviour of organic solvents through halloysite ...

    Indian Academy of Sciences (India)

    ... behaviour of three organic solvents was further validated by their crosslink density values. The thermodynamic parameters such as enthalpy, entropy and free energy of sorption were evaluated. The positive values of free energy indicate the non-spontaneity of the sorption of HNTs filled EVA in aromatic solvents at 303 K.

  13. Tritium breeding in fusion reactors

    International Nuclear Information System (INIS)

    Abdou, M.A.

    1982-10-01

    Key technological problems that influence tritium breeding in fusion blankets are reviewed. The breeding potential of candidate materials is evaluated and compared to the tritium breeding requirements. The sensitivity of tritium breeding to design and nuclear data parameters is reviewed. A framework for an integrated approach to improve tritium breeding prediction is discussed with emphasis on nuclear data requirements

  14. Biokinetic aspects of tissue-bound tritium in algae

    International Nuclear Information System (INIS)

    Strack, S.; Kistner, G.

    1978-01-01

    For the estimate of the radiation exposure of man and for the calculation of the risk of artificial tritium from nuclear power plants, organic tissue-bound tritium is of decisive importance. In model experiments, a tritium incorporation of 61 to 71% was found from tritiated water (HTO) into organic matter of planctonic algae under reproducible conditions and this was related to the theoretical value. In further experiments the tritium release from these high tritiated algae was of interest. Kept in darkness in tritium-free, non-sterile river water, so that autolytic processes and bacterial decomposition could occur, the concentration of HTO was measured over a period of three weeks. A relatively long half-life of tissue-bound tritium was found under various temperature conditions. Therefore it must be considered that a significant retention of tritium in biological matter has to be taken into account in a natural ecosystem. In streams into which the cooling water of a nuclear reactor is released all conditions are found already for a long turnover and cycling of artificial tritium in living organisms as well as the conditions for a favourable transport of tritium by food chains to man. (Auth.)

  15. Tritium permeation through iron

    International Nuclear Information System (INIS)

    Hagi, Hideki; Hayashi, Yasunori

    1989-01-01

    An experimental method for measuring diffusion coefficients and permeation rates of tritium in metals around room temperature has been established, and their values in iron have been obtained by using the method. Permeation rates of tritium and hydrogen through iron were measured by the electrochemical method in which a tritiated aqueous solution was used as a cathodic electrolyte. Tritium and hydrogen were introduced from one side of a membrane specimen by cathodic polarization, while at the other side of the specimen the permeating tritium and hydrogen were extracted by potentiostatical ionization. The amount of permeated hydrogen was obtained by integrating the anodic current, and that of tritium was determined by measuring the radioactivity of the electrolyte sampled from the extraction side. Diffusion coefficients of tritium (D T ) and hydrogen (D H ) were determined from the time lag of tritium and hydrogen permeation. D T =9x10 -10 m 2 /s and D H =4x10 -9 m 2 /s at 286 K for annealed iron specimens. These values of D T and D H were compared with the previous data of the diffusion coefficients of hydrogen and deuterium, and the isotope effect in diffusion was discussed. (orig.)

  16. Gaseous Tritium Light Sources in armament and watches industries; Tritium-Gas-Lichtquellen in der Ruestungs- und Uhrenindustrie

    Energy Technology Data Exchange (ETDEWEB)

    Amme, Marcus; Siegenthaler, Roger [mb-microtec ag, Niederwangen (Switzerland)

    2015-07-01

    The industrial application of Tritium gas enclosed in glass tubes is a modern way illuminating instruments and items wherever instant and independent readability is prerequisite. The GTLS (Gaseous Tritium Light Sources) technology follows the principle of radiation-induced luminescence and supersedes the luminous radioactive paints and their hazards such as particles erasure or heavy isotope use. Enclosure of tritium in glass is a demanding micro technology process and work needs to be performed in controlled areas due to handling of open sources. The storage and transport of the Tritium is done via licensed B(U)-containers coming from heavy water reactor sites, and disposal of radioactive Tritium wastes has to be compliant with national and international regulations for transport and waste management.

  17. Informal public transport driver behaviour and regulatory policy linkage: An expose

    Directory of Open Access Journals (Sweden)

    Smart Dumba

    2017-09-01

    Full Text Available Background: Literature on the negative socio-economic and environmental externalities generated by informal public transport (IPT in developing countries is vast, vibrant and growing fast. These externalities include but are not limited to noise, air and land pollution, accidents and, more importantly, a source of congestion (human and vehicular because of poor driver behaviour. In this article, the research does not seek to reinstate these, but rather, it argues that poor driver behaviour is a dependent variable to some regulatory policy stimuli. Yet, an extensive literature survey has shown that the driver behaviour and urban transport regulation linkage remain little explored. Objective: The purpose of this article was to unpack the relationship between informal public transport driver behaviour and the prevailing regulatory framework. Method: Based on a case study of Harare, Zimbabwe, the researcher adopted a mixed-methods paradigm and interrogated the prevailing urban public transport regulatory regimes and applied professional judgement, oral interviews backed by some quantitative data and relate these to obtaining IPT driver behavioural characteristics. Results: Poor driver behaviour exhibited by IPT were generated, exacerbated and or eased by the prevailing regulatory policy. This is well depicted through an IPT driver behaviour and regulation loop reinforcing diagram. Conclusion: Following this argument, the article cautions policy makers and urban managers alike that direct approaches and interventions when trying to regulate IPT poor driver behaviour and its secondary negative effects will be futile as long as the regulatory policy remains the same. Failure to recognise and connect the dots between IPT driver behaviour and policy partly explains why globally, the IPT sector has proved difficult in prohibiting, restructuring or even formalising it.

  18. Informal public transport driver behaviour and regulatory policy linkage: An expose

    Directory of Open Access Journals (Sweden)

    Smart Dumba

    2017-01-01

    Full Text Available Background: Literature on the negative socio-economic and environmental externalities generated by informal public transport (IPT in developing countries is vast, vibrant and growing fast. These externalities include but are not limited to noise, air and land pollution, accidents and, more importantly, a source of congestion (human and vehicular because of poor driver behaviour. In this article, the research does not seek to reinstate these, but rather, it argues that poor driver behaviour is a dependent variable to some regulatory policy stimuli. Yet, an extensive literature survey has shown that the driver behaviour and urban transport regulation linkage remain little explored.Objective: The purpose of this article was to unpack the relationship between informal public transport driver behaviour and the prevailing regulatory framework.Method: Based on a case study of Harare, Zimbabwe, the researcher adopted a mixed-methods paradigm and interrogated the prevailing urban public transport regulatory regimes and applied professional judgement, oral interviews backed by some quantitative data and relate these to obtaining IPT driver behavioural characteristics.Results: Poor driver behaviour exhibited by IPT were generated, exacerbated and or eased by the prevailing regulatory policy. This is well depicted through an IPT driver behaviour and regulation loop reinforcing diagram.Conclusion: Following this argument, the article cautions policy makers and urban managers alike that direct approaches and interventions when trying to regulate IPT poor driver behaviour and its secondary negative effects will be futile as long as the regulatory policy remains the same. Failure to recognise and connect the dots between IPT driver behaviour and policy partly explains why globally, the IPT sector has proved difficult in prohibiting, restructuring or even formalising it.

  19. Experience in handling concentrated tritium

    International Nuclear Information System (INIS)

    Holtslander, W.J.

    1985-12-01

    The notes describe the experience in handling concentrated tritium in the hydrogen form accumulated in the Chalk River Nuclear Laboratories Tritium Laboratory. The techniques of box operation, pumping systems, hydriding and dehydriding operations, and analysis of tritium are discussed. Information on the Chalk River Tritium Extraction Plant is included as a collection of reprints of papers presented at the Dayton Meeting on Tritium Technology, 1985 April 30 - May 2

  20. Problems of anthropogenic tritium limitation

    Directory of Open Access Journals (Sweden)

    Kochetkov О.A.

    2013-12-01

    Full Text Available This article contains the current situation in respect to the environmental concentrations of anthropogenic and natural tritium. There are presented and analyzed domestic standards for НТО of all Radiation Safety Standards (NRB, as well as the regulations analyzed for tritium in drinking water taken in other countries today. This article deals with the experience of limitation of tritium and focuses on the main problem of rationing of tritium — rationing of organically bound tritium.

  1. Modelling the Environmental Transfer of Tritium and Carbon-14 to Biota and Man. Report of the Tritium and Carbon-14 Working Group of EMRAS Theme 1

    International Nuclear Information System (INIS)

    2012-01-01

    Hydrogen and carbon are biologically-regulated, essential elements that are highly mobile in the environment and the human body. As isotopes of these elements, tritium and 14 C enter freely into water (in the case of tritium), plants, animals and humans. This complex behaviour means that there are substantial uncertainties in the predictions of models that calculate the transfer of tritium and 14 C through the environment. The EMRAS Tritium/C14 Working Group (WG) was set up to establish the confidence that can be placed in the predictions of such models, to recommend improved modelling approaches, and to encourage experimental work leading to the development of data sets for model testing. The activities of the WG focused on the assessment of models for organically bound tritium (OBT) formation and translocation in plants and animals, the area where model uncertainties are largest. Environmental 14 C models were also addressed because the dynamics of carbon and OBT are similar. The goals of the WG were achieved primarily through nine test scenarios in which model predictions were compared with observations obtained in laboratory or field studies. Seven of the scenarios involved tritium, covering terrestrial and aquatic ecosystems and steady-state and dynamic conditions. The remaining two scenarios concerned 14 C, one addressing steady-state concentrations in plants and the other time-dependent concentrations in animals. The WG also considered one model intercomparison exercise involving the calculation of doses following a hypothetical, short-term release of tritium to the atmosphere in a farming area. Finally, the WG discussed the nature of OBT and proposed a definition to promote common understanding and usage within the international tritium community. The models used by the various participants varied in complexity from simple specific activity approaches to dynamic compartment models and process-oriented models, in which the various transfer processes were

  2. Tritium protective clothing

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, T. P.; Easterly, C. E.

    1979-06-01

    Occupational exposures to radiation from tritium received at present nuclear facilities and potential exposures at future fusion reactor facilities demonstrate the need for improved protective clothing. Important areas relating to increased protection factors of tritium protective ventilation suits are discussed. These areas include permeation processes of tritium through materials, various tests of film permeability, selection and availability of suit materials, suit designs, and administrative procedures. The phenomenological nature of film permeability calls for more standardized and universal test methods, which would increase the amount of directly useful information on impermeable materials. Improvements in suit designs could be expedited and better communicated to the health physics community by centralizing devlopmental equipment, manpower, and expertise in the field of tritium protection to one or two authoritative institutions.

  3. Tritium waste package

    Science.gov (United States)

    Rossmassler, Rich; Ciebiera, Lloyd; Tulipano, Francis J.; Vinson, Sylvester; Walters, R. Thomas

    1995-01-01

    A containment and waste package system for processing and shipping tritium xide waste received from a process gas includes an outer drum and an inner drum containing a disposable molecular sieve bed (DMSB) seated within outer drum. The DMSB includes an inlet diffuser assembly, an outlet diffuser assembly, and a hydrogen catalytic recombiner. The DMSB absorbs tritium oxide from the process gas and converts it to a solid form so that the tritium is contained during shipment to a disposal site. The DMSB is filled with type 4A molecular sieve pellets capable of adsorbing up to 1000 curies of tritium. The recombiner contains a sufficient amount of catalyst to cause any hydrogen add oxygen present in the process gas to recombine to form water vapor, which is then adsorbed onto the DMSB.

  4. Tritium protective clothing

    International Nuclear Information System (INIS)

    Fuller, T.P.; Easterly, C.E.

    1979-06-01

    Occupational exposures to radiation from tritium received at present nuclear facilities and potential exposures at future fusion reactor facilities demonstrate the need for improved protective clothing. Important areas relating to increased protection factors of tritium protective ventilation suits are discussed. These areas include permeation processes of tritium through materials, various tests of film permeability, selection and availability of suit materials, suit designs, and administrative procedures. The phenomenological nature of film permeability calls for more standardized and universal test methods, which would increase the amount of directly useful information on impermeable materials. Improvements in suit designs could be expedited and better communicated to the health physics community by centralizing devlopmental equipment, manpower, and expertise in the field of tritium protection to one or two authoritative institutions

  5. Tritium in the environment: a critical synthesis of knowledge

    International Nuclear Information System (INIS)

    Garnier-Laplace, J.; Adam-Guillermin, C.; Antonelli, C.; Beaugelin-Seiller, K.; Boyer, P.; Bailly du Bois, P.; Fievet, B.; Masson, M.; Gariel, J.C.; Pierrard, O.; Renaud, P.; Roussel-Debet, S.; Gurrarian, R.; Le Dizes-Maurel, S.; Maro, D.

    2009-01-01

    The authors first outline that tritium is, along with carbon 14, the main radionuclide in France in terms of activity released by nuclear facilities, whatever it concerns gaseous or liquid releases. They describe its behaviour, its various forms in the atmosphere and in the ecosystems, its transfer to plants (results of surveys are evoked which seem to demonstrate that there is no significant bio-accumulation). They comment the current knowledge and results of surveys about the presence of tritium in land and sea animals, and about the toxicity of tritium for non-human organisms

  6. PRODUCTION OF TRITIUM

    Science.gov (United States)

    Jenks, G.H.; Shapiro, E.M.; Elliott, N.; Cannon, C.V.

    1963-02-26

    This invention relates to a process for the production of tritium by subjecting comminuted solid lithium fluoride containing the lithium isotope of atomic mass number 6 to neutron radiation in a self-sustaining neutronic reactor. The lithium fiuoride is heated to above 450 deg C. in an evacuated vacuum-tight container during radiation. Gaseous radiation products are withdrawn and passed through a palladium barrier to recover tritium. (AEC)

  7. Selected radionuclides. Tritium, carbon-14, krypton-85, strontium-90, iodine, caesium 137, radon, plutonium

    International Nuclear Information System (INIS)

    1983-01-01

    The release of radioactive materials to the environment potentially exposes populations to ionizing radiation and increases the risk of incurring deleterious health effects. The associations of released amounts to effects establish the health criteria for radionuclides. This report provides background information in establishing such health criteria for 14 C, 85 Kr, 90 Sr, 137 Cs, Radon, Plutonium, Iodine and Tritium, including environmental behaviour, sources, transport to man and dosimetry. A brief summary of the general aspects of radiation effects and of radiation protection considerations is presented

  8. Ductile fracture behaviour of primary heat transport piping material ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    1. Introduction. The design of primary heat transport piping (PHT) of nuclear reactors has to ensure that uncontrolled failure does not occur under normal, faulted or accidental service conditions. One of the most severe failure scenarios traditionally envisaged is instantaneous double-ended guillotine break (DEGB), which ...

  9. Molecular transport behaviour of organic solvents through halloysite ...

    Indian Academy of Sciences (India)

    used in the recent environment. The diffusion and transport properties of polymers were found to be strongly dependent on factors such as the nature of the polymer, the nature of the penetrant, crosslink den- sity, temperature, etc. Another important factor is the nature of filler incorporated into the polymer matrix. Reinforcing.

  10. Booklet on behavioural causes and remedies associated with transportation accidents

    CSIR Research Space (South Africa)

    Krige, PD

    2003-08-01

    Full Text Available of the background and supporting statistics. Its emphasis is on presenting the recommendations in an accessible format. The booklet first identifies the key trends and hazards associated with track-bound underground transportation. It then explores what learning...

  11. Tritium at Jefferson Lab

    Science.gov (United States)

    Bane, Jason; Jefferson Lab Hall A Collaboration Collaboration

    2017-09-01

    Jefferson Lab's recently upgraded accelerator will provide the perfect opportunity to increase the quality and quantity of the electron scattering world data on tritium. Tritium, the radioactive isotope of hydrogen with a half-life of 12 years, was last used in a large scale electron scattering experiment a few decades ago. This Fall Jefferson Lab will play host to a set of very exciting electron scattering experiments involving tritium. A 25 cm aluminum cell will be filled with 1 kCi of tritium with an internal pressure of approximately 200 psi at 295 kelvin. The tritium target will first see a 10.6 GeV beam to probe the deep inelastic scattering region to study the down to up quark ratio and the EMC effect. Then the beam will be set to 4.3 GeV to investigate SRCs and momentum distributions in the quasi-elastic scattering regime. If time permits, elastic scattering will be used to extract the ratio of the charge radius of tritium and helium3.

  12. Tritium in nuclear power plants

    International Nuclear Information System (INIS)

    Badyaev, V.V.; Egorov, Yu.A.; Sklyarov, V.P.; Stegachev, G.V.

    1981-01-01

    The problem of tritium formation during NPP operation is considered on the basis of available published data. Tritium characteristics are given, sources of the origin of natural and artificial tritium are described. NPP contribution to the total tritium amount in the environment is determined, as well as contribution of each process in the reactor to the quantity of tritium, produced at the NPP. Thermal- and fast-neutron reactions with tritium production are shown, their contribution to the total amount of tritium in a coolant is estimated, taking into account the type of reactor. Data on tritium content in NPP wastes and in the air of working premises are presented. Methods for sampling and sample preparation to measurements as well as the appropriate equipment are considered. Design of the gas-discharge counter of internal filling, used for measuring tritium activity in samples is described [ru

  13. Tritium in the environment: a critical synthesis of knowledge; Le tritium dans l'environnement: synthese critique des connaissances

    Energy Technology Data Exchange (ETDEWEB)

    Garnier-Laplace, J.; Adam-Guillermin, C.; Antonelli, C.; Beaugelin-Seiller, K.; Boyer, P. [Institut de Radioprotection et de Surete Nucleaire, Direction de l' Environnement et de l' Intervention, 13 - Saint Paul Lez Durance (France); Bailly du Bois, P.; Fievet, B.; Masson, M. [Institut de Radioprotection et de Surete Nucleaire, LRC, 50 - Cherbourg Octeville (France); Gariel, J.C.; Pierrard, O.; Renaud, P.; Roussel-Debet, S. [Institut de Radioprotection et de Surete Nucleaire, DEI, 78 - Le Vesinet (France); Gurrarian, R. [Institut de Radioprotection et de Surete Nucleaire, DEI/STME/LMRE, 91 - Orsay (France); Le Dizes-Maurel, S.; Maro, D. [Institut de Radioprotection et de Surete Nucleaire, DEI/SECRE/LME, 13 - Saint Paul Lez Durance (France)

    2009-07-01

    The authors first outline that tritium is, along with carbon 14, the main radionuclide in France in terms of activity released by nuclear facilities, whatever it concerns gaseous or liquid releases. They describe its behaviour, its various forms in the atmosphere and in the ecosystems, its transfer to plants (results of surveys are evoked which seem to demonstrate that there is no significant bio-accumulation). They comment the current knowledge and results of surveys about the presence of tritium in land and sea animals, and about the toxicity of tritium for non-human organisms

  14. Associations between narrative transportation, risk perception and behaviour intentions following narrative messages about skin cancer.

    Science.gov (United States)

    Dillard, Amanda J; Ferrer, Rebecca A; Welch, Jessica D

    2017-10-04

    Narrative messages may be an effective strategy to increase risk perceptions and motivate preventive behaviours related to cancer. The aim of this research was to examine associations between narrative transportation (i.e. psychological absorption into a narrative), risk perceptions, and intentions following narrative messages about skin cancer. In two studies, women who reported indoor tanning read first-person narrative messages about skin cancer. We examined associations between narrative transportation and the women's responses to the narratives, including risk perceptions for skin cancer and behaviour intentions to reduce risk. Associations between transportation, knowledge and worry were also examined. Greater transportation was associated with higher intentions to perform skin self-examination, talk to one's doctor about skin cancer, and look for more information. Greater transportation was also associated with higher gut feelings of risk and higher worry about skin cancer, but not deliberative risk perceptions or knowledge from the message. Additional analyses showed that after controlling for risk perception and worry, transportation had unique associations with some behaviour intentions. Findings suggest that narrative transportation may be an important component to the persuasion of cancer narratives. Future research should explore ideas such as the role of the experiential system in narratives' influence.

  15. Atmospheric Modelling of Tritium forms transport: review of capabilities and R and D needs for the assessment of fusion facilities environmental impact

    International Nuclear Information System (INIS)

    Castro, P.; Velarde, M.; Ardao, J.; Perlado, J. M.; Sedano, L.

    2012-01-01

    The work model in detail the tritium forms dispersion and dosimetric impact of selected environmental patterns both inland and in-sea using real topography and forecast meteo data (ECMWF/FLEXPART). We explore specific values of this ratio in different levels and we examine the influence of meteorological conditions in the HTO behavior for 24 hours. For this purpose we have used a tool which consists on a coupled Lagrangian.

  16. Ductile fracture behaviour of primary heat transport piping material ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Heat transport piping material of nuclear reactors. 169. Table 1. Chemical composition of. SA333, Grade 6 steel in wt%. C. Mn. Si. S. P. 0·18 0·90 0·25 0·02 0·02 room temperature. The tensile flow curve of the steel exhibited prominent yield-point effect accompanied by non-hardening strain propagation (Lüders strain) of ...

  17. Tritium Assay and Dispensing of KEPRI Tritium Lab

    International Nuclear Information System (INIS)

    Sohn, S. H.; Song, K. M.; Lee, S. K.; Lee, K.W.; Ko, B. W.

    2009-01-01

    The Wolsong Tritium Removal Facility(WTRF) has been constructed to reduce tritium levels in the heavy water systems and environmental emissions at the site. The WTRF was designed to process 100 kg/h of heavy water with the overall tritium extraction efficiency of 97% per single pass and to produce ∼700 g of tritium as T2 per year at the feed concentration of 0.37 TBq/kg. The high purity tritium greater than 99% is immobilized as a metal hydride to secure its long term storage. The recovered tritium will be made available for industrial uses and some research applications in the future. Then KEPRI is constructing the tritium lab. to build-up infrastructure to support tritium research activities and to support tritium control and accountability systems for tritium export. This paper describes the initial phases of the tritium application program including the laboratory infrastructure to support the tritium related R and D activities and the tritium controls in Korea

  18. Behavioural Models for Route Choice of Passengers in Multimodal Public Transport Networks

    DEFF Research Database (Denmark)

    Anderson, Marie Karen

    The subject of this thesis is behavioural models for route choice of passengers in multimodal public transport networks. While research in sustainable transport has dedicated much attention toward the determinants of choice between car and sustainable travel options, it has devoted less attention...... and processed in this study. The characteristics of the collected data are analysed and the actual choices of the public transport passengers are revealed in the thesis. The data were map-matched to the GIS network of the area and quality controlled in a multi-step procedure. From the choice set generation...... perspective, this thesis generates attractive routes for the origindestination pair of each traveller. The problem is not trivial when considering the combinatorial iv Behavioural models for route choice of passengers in multimodal public transport networks nature of the problem. The dense network...

  19. Detection of tritium sorption on four soil materials

    International Nuclear Information System (INIS)

    Teng Yanguo; Zuo Rui; Wang Jinsheng; Hu Qinhong; Sun Zongjian; Zeng Ni

    2011-01-01

    In order to measure groundwater age and design nuclear waste disposal sites, it is important to understand the sorption behavior of tritium on soils. In this study, batch tests were carried out using four soils from China: silty clays from An County and Jiangyou County in Sichuan Province, both of which could be considered candidate sites for Very Low Level Waste disposal; silty sand from Beijing; and loess from Yuci County in Shanxi Province, a typical Chinese loess region. The experimental results indicated that in these soil media, the distribution coefficient of tritium is slightly influenced by adsorption time, water/solid ratio, initial tritium specific activity, pH, and the content of humic and fulvic acids. The average distribution coefficient from all of these influencing factors was about 0.1-0.2 mL/g for the four types of soil samples. This relatively modest sorption of tritium in soils needs to be considered in fate and transport studies of tritium in the environment. - Research highlights: → In this study, batch sorption tests validate the adsorption of tritium on all of the four tested soil samples collected in China, and the distribution coefficient is found to be non-zero and less than 0.4 mL/g. The experimental results indicated that in these soil media, the distribution coefficient of tritium is slightly influenced by adsorption time, water/solid ratio, initial tritium specific activity, pH, and the content of humic and fulvic acids. This relatively modest sorption of tritium in soils needs to be considered in fate and transport studies of tritium in the environment.

  20. Environmental health-risk assessment for tritium releases from the National Tritium Labeling Facility (NTLF) at Lawrence Berkeley Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    McKone, T.E.; Brand, K.P.

    1994-12-01

    This report is a health risk assessment that addresses continuous releases of tritium to the environment from the National Tritium Labeling Facility (NTLF) at the Lawrence Berkeley Laboratory (LBL). The NTLF contributes approximately 95% of all tritium releases from LBL. Transport and transformation models were used to determine the movement of tritium releases from the NRLF to the air, surface water, soils, and plants and to determine the subsequent doses to humans. These models were calibrated against environmental measurements of tritium levels in the vicinity of the NTLF and in the surrounding community. Risk levels were determined for human populations in each of these zones. Risk levels to both individuals and populations were calculated. In this report population risks and individual risks were calculated for three types of diseases--cancer, heritable genetic effects, and developmental and reproductive effects.

  1. Environmental health-risk assessment for tritium releases from the National Tritium Labeling Facility (NTLF) at Lawrence Berkeley Laboratory

    International Nuclear Information System (INIS)

    McKone, T.E.; Brand, K.P.

    1994-12-01

    This report is a health risk assessment that addresses continuous releases of tritium to the environment from the National Tritium Labeling Facility (NTLF) at the Lawrence Berkeley Laboratory (LBL). The NTLF contributes approximately 95% of all tritium releases from LBL. Transport and transformation models were used to determine the movement of tritium releases from the NRLF to the air, surface water, soils, and plants and to determine the subsequent doses to humans. These models were calibrated against environmental measurements of tritium levels in the vicinity of the NTLF and in the surrounding community. Risk levels were determined for human populations in each of these zones. Risk levels to both individuals and populations were calculated. In this report population risks and individual risks were calculated for three types of diseases--cancer, heritable genetic effects, and developmental and reproductive effects

  2. Hazards of exposure to tritium and tritium oxide

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, R.C.; Kornberg, H.A.

    1954-01-01

    Experimental data pertinent to the evaluation of hazards involved in the exposure of personnel to tritium and tritium oxide are reviewed. Conclusions are drawn and recommendations made with regard to the control of these hazards.

  3. Final programmatic environmental impact statement for tritium supply and recycling

    International Nuclear Information System (INIS)

    1995-10-01

    Tritium, a radioactive gas used in all of the Nation's nuclear weapons, has a short half-life and must be replaced periodically in order for the weapon to operate as designed. Currently, there is no capability to produce the required amounts of tritium within the Nuclear Weapons Complex. The PEIS for Tritium Supply and Recycling evaluates the alternatives for the siting, construction, and operation of tritium supply and recycling facilities at each of five candidate sites: the Idaho National Engineering Laboratory, the Nevada Test Site, the Oak Ridge Reservation, the Pantex Plant, and the Savannah River Site. Alternatives for new tritium supply and recycling facilities consist of four different tritium supply technologies: Heavy Water Reactor, Modular High Temperature Gas-Cooled Reactor, Advanced Light Water Reactor, and Accelerator Production of Tritium. The PEIS also evaluates the impacts of the DOE purchase of an existing operating or partially completed commercial light water reactor or the DOE purchase of irradiation services contracted from commercial power reactors. Additionally, the PEIS includes an analysis of multipurpose reactors that would produce tritium, dispose of plutonium, and produce electricity. Evaluation of impacts on land resources, site infrastructure, air quality and acoustics, water resources, geology and soils, biotic resources, cultural and paleontological resources, socioeconomics, radiological and hazardous chemical impacts during normal operation and accidents to workers and the public, waste management, and intersite transport are included in the assessment

  4. Tritium emissions reduction facility (TERF)

    International Nuclear Information System (INIS)

    Lamberger, P.H.; Hedley, W.H.

    1993-01-01

    Tritium handling operations at Mound include production of tritium-containing devices, evaluation of the stability of tritium devices, tritium recovery and enrichment, tritium process development, and research. In doing this work, gaseous process effluents containing 400,000 to 1,000,000 curies per year of tritium are generated. These gases must be decontaminated before they can be discharged to the atmosphere. They contain tritium as elemental hydrogen, as tritium oxide, and as tritium-containing organic compounds at low concentrations (typically near one ppm). The rate at which these gases is generated is highly variable. Some tritium-containing gas is generated at all times. The systems used at Mound for capturing tritium from process effluents have always been based on the open-quotes oxidize and dryclose quotes concept. They have had the ability to remove tritium, regardless of the form it was in. The current system, with a capacity of 1.0 cubic meter of gas per minute, can effectively remove tritium down to part-per-billion levels

  5. Tritium in the Channel; Le tritium en Manche

    Energy Technology Data Exchange (ETDEWEB)

    Masson, M.; Fievet, B.; Bailly-Du-Bois, P. [Laboratoire de Radioecologie de Cherbourg-Octeville, IRSN /DEI /SECRE, 50 (France); Olivier, A.; Tenailleau, L. [Groupe d' Etudes Atomiques, EAMEA, 50 - Cherbourg (France)

    2009-07-01

    After having recalled that sea waters entering the Channel exhibit a natural concentration of tritium, the authors outline that spent nuclear fuel reprocessing plants are now the main sources of tritium for marine ecosystems as some oceanographic campaigns showed it. If data about the presence of tritium in water are numerous, data concerning the presence of tritiated water and of organically bound tritium in organisms are much less frequent. However, some surveys have been performed along the Channel French coasts

  6. Tritium Systems Test Facility

    International Nuclear Information System (INIS)

    Cafasso, F.A.; Maroni, V.A.; Smith, W.H.; Wilkes, W.R.; Wittenberg, L.J.

    1978-01-01

    This TSTF proposal has two principal objectives. The first objective is to provide by mid-FY 1981 a demonstration of the fuel cycle and tritium containment systems which could be used in a Tokamak Experimental Power Reactor for operation in the mid-1980's. The second objective is to provide a capability for further optimization of tritium fuel cycle and environmental control systems beyond that which is required for the EPR. The scale and flow rates in TSTF are close to those which have been projected for a prototype experimental power reactor (PEPR/ITR) and will permit reliable extrapolation to the conditions found in an EPR. The fuel concentrations will be the same as in an EPR. Demonstrations of individual components of the deuterium-tritium fuel cycle and of monitoring, accountability and containment systems and of a maintenance methodology will be achieved at various times in the FY 1979-80 time span. Subsequent to the individual component demonstrations--which will proceed from tests with hydrogen (and/or deuterium) through tracer levels of tritium to full operational concentrations--a complete test and demonstration of the integrated fuel processing and tritium containment facility will be performed. This will occur near the middle of FY 1981. Two options were considered for the TSTF: (1) The modification of an existing building and (2) the construction of a new facility

  7. Permeability of protective coatings to tritium

    International Nuclear Information System (INIS)

    Braun, J.M.

    1987-10-01

    The permeability of four protective coatings to tritium gas and tritiated water was investigated. The coatings, including two epoxies, one vinyl and one urethane, were selected for their suitability in CANDU plant service in Ontario Hydro. Sorption rates of tritium gas into the coatings were considerably larger than for tritiated water, by as much as three to four orders of magnitude. However, as a result of the very large solubility of tritiated water in the coatings, the overall permeability to tritium gas and tritiated water are comparable, being somewhat larger for HTO. Marked differences were also evident among the four coatings, the vinyl proving to be unique in behaviour and morphology. Because of a highly porous surface structure water condensation takes place at high relative humidities, leading to an abnormally high retention of free water. Desorption rates from the four coatings were otherwise quite similar. Of practical importance was the observation that more effective desorption of tritiated water could be carried out at relatively high humidities, in this case 60%. It was believed that isotopic exchange was responsible for this phenomenon. It appears that epoxy coatings having a high pigment-to-binder ratio are most suited for coating concrete in tritium handling facilities

  8. Handling of tritium at TFTR

    International Nuclear Information System (INIS)

    Pierce, C.W.; Howe, H.J.; Yemin, L.; Lind, K.

    1977-01-01

    Some of the engineering approaches taken at TFTR for the tritium control systems are discussed as the requirements being placed on the tritium systems by the operating scenarios of the Tokamak. The tritium control systems presently being designed for TFTR will limit the annual release to the environment to less than 100 curies

  9. Tritium effluent removal system

    International Nuclear Information System (INIS)

    Lamberger, P.H.; Gibbs, G.E.

    1978-01-01

    An air detritiation system has been developed and is in routine use for removing tritium and tritiated compounds from glovebox effluent streams before they are released to the atmosphere. The system is also used, in combination with temporary enclosures, to contain and decontaminate airborne releases resulting from the opening of tritium containment systems during maintenance and repair operations. This detritiation system, which services all the tritium handling areas at Mound Facility, has played an important role in reducing effluents and maintaining them at 2 percent of the level of 8 y ago. The system has a capacity of 1.7 m 3 /min and has operated around the clock for several years. A refrigerated in-line filtration system removes water, mercury, or pump oil and other organics from gaseous waste streams. The filtered waste stream is then heated and passed through two different types of oxidizing beds; the resulting tritiated water is collected on molecular sieve dryer beds. Liquids obtained from regenerating the dryers and from the refrigerated filtration system are collected and transferred to a waste solidification and packaging station. Component redundancy and by-pass capabilities ensure uninterrupted system operation during maintenance. When processing capacity is exceeded, an evacuated storage tank of 45 m 3 is automatically opened to the inlet side of the system. The gaseous effluent from the system is monitored for tritium content and recycled or released directly to the stack. The average release is less than 1 Ci/day. The tritium effluent can be reduced by isotopically swamping the tritium; this is accomplished by adding hydrogen prior to the oxidizer beds, or by adding water to the stream between the two final dryer beds

  10. Development of tritium technology at the Tritium Systems Test Assembly

    International Nuclear Information System (INIS)

    Anderson, J.L.; Bartlit, J.R.

    1982-01-01

    The Tritium Systems Test Assembly (TSTA) at the Los Alamos National Laboratory is dedicated to the development, demonstration, and interfacing of technologies related to the deuterium-tritium fuel cycle for large scale fusion reactor systems starting with the Fusion Engineering Device (FED) or the International Tokamak Reactor (INTOR). This paper briefly describes the fuel cycle and safety systems at TSTA including the Vacuum Facility, Fuel Cleanup, Isotope Separation, Transfer Pumping, Emergency Tritium Cleanup, Tritium Waste Treatment, Tritium Monitoring, Data Acquisition and Control, Emergency Power and Gas Analysis systems. Discussed in further detail is the experimental program proposed for the startup and testing of these systems

  11. Monitoring of tritium

    Science.gov (United States)

    Corbett, James A.; Meacham, Sterling A.

    1981-01-01

    The fluid from a breeder nuclear reactor, which may be the sodium cooling fluid or the helium reactor-cover-gas, or the helium coolant of a gas-cooled reactor passes over the portion of the enclosure of a gaseous discharge device which is permeable to hydrogen and its isotopes. The tritium diffused into the discharge device is radioactive producing beta rays which ionize the gas (argon) in the discharge device. The tritium is monitored by measuring the ionization current produced when the sodium phase and the gas phase of the hydrogen isotopes within the enclosure are in equilibrium.

  12. ARIES-I tritium system

    International Nuclear Information System (INIS)

    Sze, D.K.; Tam, S.W.; Billone, M.C.; Hassanein, A.M.; Martin, R.

    1990-09-01

    A key safety concern in a D-T fusion reactor is the tritium inventory. There are three components in a fusion reactor with potentially large inventories, i.e., the blanket, the fuel processing system and the plasma facing components. The ARIES team selected the material combinations, decided the operating conditions and refined the processing systems, with the aiming of minimizing the tritium inventories and leakage. The total tritium inventory for the ARIES-I reactor is only 700 g. This paper discussed the calculations and assumptions we made for the low tritium inventory. We also addressed the uncertainties about the tritium inventory. 13 refs., 2 figs., 3 tabs

  13. Tritium retention in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Dylla, H.F.; Wilson, K.L. (eds.)

    1988-04-01

    This report discusses the materials physics related to D-T operation in TFTR. Research activities are described pertaining to basic studies of hydrogenic retention in graphite, hydrogen recycling phenomena, first-wall and limiter conditioning, surface analysis of TFTR first-wall components, and estimates of the tritium inventory.

  14. Properties of tritium and its compounds

    International Nuclear Information System (INIS)

    Belovodskij, L.F.; Gaevoj, V.K.; Grishmanovskij, V.I.

    1985-01-01

    Ways of tritium preparation and different aspects of its application are considered. Physicochemical properties of this isotope and some compounds of it - tritium oxides, lithium, titanium, zirconium, uranium tritides, tritium organic compounds - are discussed. In particular, diffusion of tritium and its oxide through different materials, tritium oxidation processes, decomposition of tritium-containing compounds under the action of self-radiation are considered. Main radiobiological tritium properties are described

  15. Progress in tritium retention and release modeling for ceramic breeders

    International Nuclear Information System (INIS)

    Raffray, A.R.; Federici, G.; Billone, M.C.; Tanaka, S.

    1994-01-01

    Tritium behavior in ceramic breeder blankets is a key design issue for this class of blanket because of its impact on safety and fuel self-sufficiency. Over the past 10-15 years, substantial theoretical and experimental efforts have been dedicated world-wide to develop a better understanding of tritium transport in ceramic breeders. Models that are available today seem to cover reasonably well all the key physical transport and trapping mechanisms. They have allowed for reasonable interpretation and reproduction of experimental data and have helped in pointing out deficiencies in material property data base, in providing guidance for future experiments, and in analyzing blanket tritium behavior. This paper highlights the progress in tritium modeling over the last decade. Key tritium transport mechanisms are briefly described along with the more recent and sophisticated models developed to help understand them. Recent experimental data are highlighted and model calibration and validation discussed. Finally, example applications to blanket cases are shown as illustration of progress in the prediction of ceramic breeder blanket tritium inventory

  16. Modulatory role of ascorbic acid on behavioural responses of pigs transported by road during the harmattan season.

    Science.gov (United States)

    Adenkola, A Y; Ayo, J O; Sackey, A K B; Adelaiye, A B

    2011-11-23

    Experiments were performed on adult local pigs with the aim of investigating the modulatory role of ascorbic acid (AA) on their behavioural responses to 4-h, road transportation during the harmattan season. Sixteen adult pigs administered with AA at the dose of 250 mg/kg dissolve in sterile water served as experimental animals, and 13 others administered with sterile water were used as control animals. All the pigs were transported for 4-h at speed of 40-50 km/h covering a distance of 140 km. The behavioural activities were determined before and after road transportation. The behavioural activities were higher (Ptransportation. In conclusion, AA ameliorates behavioural stress induced by road transportation of pigs for 4 h and may be of value in reducing adverse effects of road transportation in pigs.

  17. A descriptive study on public transport user behaviour from Live Bus Arrivals

    OpenAIRE

    Dell’Amico, M.; Hadjidimitriou, S.; Kaparias, I.

    2014-01-01

    In order to offer public transport that meet citizens’ needs for transport and further increase the use of bus services, Public Authorities need to analyse and understand travellers behaviour. Automatic Vehicle Location (AVL) data provide information on the observed time of arrival and departure of a bus at each stop. These data are fed into an algorithm to provide information to users on the expected time of arrival at the bus stop by an on-line service. In the city of London this service is...

  18. Tritium in the aquatic environment

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, B.G.; Hoffman, F.O.; Frank, M.L.

    1986-02-01

    Tritium is of environmental importance because it is released from nuclear facilities in relatively large quantities and because it has a half life of 12.26 y. Most of the tritium released into the atmosphere eventually reaches the aqueous environment, where it is rapidly taken up by aquatic organisms. This paper reviews the current literature on tritium in the aquatic environment. Conclusions from the review, which covered studies of algae, aquatic macrophytes, invertebrates, fish, and the food chain, were that aquatic organisms incorporate tritium into their tissue-free water very rapidly and reach concentrations near those of the external medium. The rate at which tritium from tritiated water is incorporated into the organic matter of cells is slower than the rate of its incorporation into the tissue-free water. If organisms consume tritiated food, incorporation of tritium into the organic matter is faster, and a higher tritium concentration is reached than when the organisms are exposed to only tritiated water alone. Incorporation of tritium bound to molecules into the organic matter depends on the chemical form of the ''carrier'' molecule. No evidence was found that biomagnification of tritium occurs at higher trophic levels. Radiation doses from tritium releases to large populations of humans will most likely come from the consumption of contaminated water rather than contaminated aquatic food products.

  19. Tritium in the aquatic environment

    International Nuclear Information System (INIS)

    Blaylock, B.G.; Hoffman, F.O.; Frank, M.L.

    1986-02-01

    Tritium is of environmental importance because it is released from nuclear facilities in relatively large quantities and because it has a half life of 12.26 y. Most of the tritium released into the atmosphere eventually reaches the aqueous environment, where it is rapidly taken up by aquatic organisms. This paper reviews the current literature on tritium in the aquatic environment. Conclusions from the review, which covered studies of algae, aquatic macrophytes, invertebrates, fish, and the food chain, were that aquatic organisms incorporate tritium into their tissue-free water very rapidly and reach concentrations near those of the external medium. The rate at which tritium from tritiated water is incorporated into the organic matter of cells is slower than the rate of its incorporation into the tissue-free water. If organisms consume tritiated food, incorporation of tritium into the organic matter is faster, and a higher tritium concentration is reached than when the organisms are exposed to only tritiated water alone. Incorporation of tritium bound to molecules into the organic matter depends on the chemical form of the ''carrier'' molecule. No evidence was found that biomagnification of tritium occurs at higher trophic levels. Radiation doses from tritium releases to large populations of humans will most likely come from the consumption of contaminated water rather than contaminated aquatic food products

  20. Universal tritium transmitter

    International Nuclear Information System (INIS)

    Cordaro, J. V.; Wood, M.

    2008-01-01

    At the Savannah River Site and throughout the National Nuclear Security Agency (NNSA) tritium is measured using Ion or Kanne Chambers. Tritium flowing through an Ion Chamber emits beta particles generating current flow proportional to tritium radioactivity. Currents in the 1 x 10 -15 A to 1 x 10 -6 A are measured. The distance between the Ion Chamber and the electrometer in NNSA facilities can be over 100 feet. Currents greater than a few micro-amperes can be measured with a simple modification. Typical operating voltages of 500 to 1000 Volts and piping designs require that the Ion Chamber be connected to earth ground. This grounding combined with long cable lengths and low currents requires a very specialized preamplifier circuit. In addition, the electrometer must be able to supply 'fail safe' alarm signals which are used to alert personnel of a tritium leak, trigger divert systems preventing tritium releases to the environment and monitor stack emissions as required by the United States federal Government and state governments. Ideally the electrometer would be 'self monitoring'. Self monitoring would reduce the need for constant checks by maintenance personnel. For example at some DOE facilities monthly calibration and alarm checks must be performed to ensure operation. NNSA presently uses commercially available electrometers designed specifically for this critical application. The problems with these commercial units include: ground loops, high background currents, inflexibility and susceptibility to Electromagnetic Interference (EMI) which includes RF and Magnetic fields. Existing commercial electrometers lack the flexibility to accommodate different Ion Chamber designs required by the gas pressure, type of gas and range. Ideally the electrometer could be programmed for any expected gas, range and high voltage output. Commercially available units do not have 'fail safe' self monitoring capability. Electronics used to measure extremely low current must have

  1. Assessment of tritium in the Savannah River Site environment

    Energy Technology Data Exchange (ETDEWEB)

    Carlton, W.H.; Murphy, C.E. Jr.; Bauer, L.R. [and others

    1993-10-01

    This report is the first revision to a series of reports on radionuclides inn the SRS environment. Tritium was chosen as the first radionuclide in the series because the calculations used to assess the dose to the offsite population from SRS releases indicate that the dose due to tritium, through of small consequence, is one of the most important the radionuclides. This was recognized early in the site operation, and extensive measurements of tritium in the atmosphere, surface water, and ground water exist due to the effort of the Environmental Monitoring Section. In addition, research into the transport and fate of tritium in the environment has been supported at the SRS by both the local Department of Energy (DOE) Office and DOE`s Office of Health and Environmental Research.

  2. Tritium permeation losses in HYLIFE-II heat exchanger tubes

    International Nuclear Information System (INIS)

    Longhurst, G.R.; Dolan, T.J.

    1990-01-01

    Tritium permeation through the intermediate heat exchanger of the HYLIFE-II inertial fusion design concept is evaluated for routine operating conditions. The permeation process is modelled using the Lewis analogy combined with surface recombination. It is demonstrated that at very low driving potentials, permeation becomes proportional to the first power of the driving potential. The model predicts that under anticipated conditions the primary cooling loop will pass about 6% of the tritium entering it to the intermediate coolant. Possible approached to reducing tritium permeation are explored. Permeation is limited by turbulent diffusion transport through the molten salt. Hence, surface barriers with impendance factors typical of present technology can do very little to reduce permeation. Low Flibe viscosity is desirable. An efficient tritium removal system operating on the Flibe before it gets to the intermediate heat exchanger is required. Needs for further research are highlighted. 9 refs., 2 figs., 1 tab

  3. Environmental monitoring for tritium at tritium separation facility

    International Nuclear Information System (INIS)

    Varlam, C.; Stefanescu, I.; Steflea, D.; Lazar, R.E.

    2001-01-01

    The Cryogenic Pilot is an experimental project in the nuclear energy national research program, which has the aim of developing technologies for tritium and deuterium separation by cryogenic distillation. The experimental installation is located 15 km near the highest city of the area and 1 km near Olt River. An important chemical activity is developed in the area and the Experimental Cryogenic Pilot's, almost the entire neighborhood are chemical plants. It is necessary to emphasize this aspect because the sewerage system is connected with the other three chemical plants from the neighborhood. This is the reason that we progressively established elements of an environmental monitoring program well in advance of tritium operation in order to determine baseline levels. The first step was the tritium level monitoring in environmental water and waste water of industrial activity from neighborhood. In this work, a low background liquid scintillation is used to determine tritium activity concentration according to ISO 9698/1998. We measured drinking water, precipitation, river water, underground water and waste water. The tritium level was between 10 TU and 27 TU that indicates there is no source of tritium contamination in the neighborhood of Cryogenic Pilot. In order to determine baseline levels we decide to monitories monthly each location. In this paper a standard method is presented which it is used for tritium determination in water sample, the precautions needed in order to achieve reliable results, and the evolution of tritium level in different location near the Experimental Pilot Tritium and Deuterium Cryogenic Separation.(author)

  4. Evaluation of tritium release properties of advanced tritium breeders

    Energy Technology Data Exchange (ETDEWEB)

    Hoshino, T. [Breeding Functional Materials Development Group, Department of Blanket Systems Research, JAEA, Rokkasho Fusion Institute, Omotedate, Rokkasho-mura (Japan); Ochiai, K. [Fusion Neutronics Group, Department of Blanket Systems Research, JAEA, Tokai-mura (Japan); Edao, Y.; Kawamura, Y. [Tritium Technology Group, Department of Blanket Systems Research, JAEA, Tokai-mura (Japan)

    2015-03-15

    Demonstration power plant (DEMO) fusion reactors require advanced tritium breeders with high thermal stability. Lithium titanate (Li{sub 2}TiO{sub 3}) advanced tritium breeders with excess Li (Li{sub 2+x}TiO{sub 3+y}) are stable in a reducing atmosphere at high temperatures. Although the tritium release properties of tritium breeders are documented in databases for DEMO blanket design, no in situ examination under fusion neutron (DT neutron) irradiation has been performed. In this study, a preliminary examination of the tritium release properties of advanced tritium breeders was performed, and DT neutron irradiation experiments were performed at the fusion neutronics source (FNS) facility in JAEA. Considering the tritium release characteristics, the optimum grain size after sintering is <5 μm. From the results of the optimization of granulation conditions, prototype Li{sub 2+x}TiO{sub 3+y} pebbles with optimum grain size (<5 μm) were successfully fabricated. The Li{sub 2+x}TiO{sub 3+y} pebbles exhibited good tritium release properties similar to the Li{sub 2}TiO{sub 3} pebbles. In particular, the released amount of HT gas for easier tritium handling was higher than that of HTO water. (authors)

  5. Tritium concentration monitor

    International Nuclear Information System (INIS)

    Shono, Kosuke.

    1991-01-01

    A device for measuring the concentration of tritium in gaseous wastes in a power plant and a nuclear fuel reprocessing plant is reduced in the size and improved in performance. The device of the present invention pressurizes a sampling gas and cools it to a dew point. Water content in the sampling gas cooled to the dew point is condensated and recovered to a fine tube-like water content recovering container. The concentration of the recovered condensates is measured by a tritium density analyzer. With such procedures, since the specimen is pressurized, the dew point can be elevated. Accordingly, the size of the cooling device can be decreased, enabling to contribute to the reduction of the size of the entire device. Further, since the water content recovering device is formed as a fine tube, the area of contact between the specimen gas and the liquid condensated water can be reduced. Accordingly, evaporation of the liquid condensates can be prevented. (I.S.)

  6. Tritium monitoring : present status

    International Nuclear Information System (INIS)

    Rathnakaran, M.; Singh, A.N.

    1993-01-01

    The report summarizes the present status of techniques employed for the monitoring of tritium in water, air and other samples. A brief mention of the work done by numerous workers in the field, critical comments about the work and a fairly exhaustive list of references about the work done during the last 4 decades has been presented. On-line monitoring on real time basis in nuclear reactors is also discussed. (author). 83 refs., 10 refs., 2 tabs

  7. Effects of tritium in elastomers

    International Nuclear Information System (INIS)

    Zapp, P.E.

    1982-01-01

    Elastomers are used as flange gaskets in the piping system of the Savannah River Plant tritium facilities. A number of elastomers is being examined to identify those compounds more radiation-resistant than the currently specified Buna-N rubber and to study the mechanism of tritium radiation damage. Radiation resistance is evaluated by compression set tests on specimens exposed to about 1 atm tritium for several months. Initial results show that ethylene-propylene rubber and three fluoroelastomers are superior to Buna-N. Off-gassing measurements and autoradiography show that retained surface absorption of tritium varies by more than an order of magnitude among the different elastomer compounds. Therefore, tritium solubility and/or exchange may have a role in addition to that of chemical structure in the damage process. Ongoing studies of the mechanism of radiation damage include: (1) tritium absorption kinetics, (2) mass spectroscopy of radiolytic products, and (3) infrared spectroscopy

  8. Effects of tritium in elastomers

    Energy Technology Data Exchange (ETDEWEB)

    Zapp, P.E.

    1982-01-01

    Elastomers are used as flange gaskets in the piping system of the Savannah River Plant tritium facilities. A number of elastomers is being examined to identify those compounds more radiation-resistant than the currently specified Buna-N rubber and to study the mechanism of tritium radiation damage. Radiation resistance is evaluated by compression set tests on specimens exposed to about 1 atm tritium for several months. Initial results show that ethylene-propylene rubber and three fluoroelastomers are superior to Buna-N. Off-gassing measurements and autoradiography show that retained surface absorption of tritium varies by more than an order of magnitude among the different elastomer compounds. Therefore, tritium solubility and/or exchange may have a role in addition to that of chemical structure in the damage process. Ongoing studies of the mechanism of radiation damage include: (1) tritium absorption kinetics, (2) mass spectroscopy of radiolytic products, and (3) infrared spectroscopy.

  9. Metabolism of organically bound tritium

    International Nuclear Information System (INIS)

    Travis, C.C.

    1984-01-01

    The classic methodology for estimating dose to man from environmental tritium ignores the fact that organically bound tritium in foodstuffs may be directly assimilated in the bound compartment of tissues without previous oxidation. We propose a four-compartment model consisting of a free body water compartment, two organic compartments, and a small, rapidly metabolizing compartment. The utility of this model lies in the ability to input organically bound tritium in foodstuffs directly into the organic compartments of the model. We found that organically bound tritium in foodstuffs can increase cumulative total body dose by a factor of 1.7 to 4.5 times the free body water dose alone, depending on the bound-to-loose ratio of tritium in the diet. Model predictions are compared with empirical measurements of tritium in human urine and tissue samples, and appear to be in close agreement. 10 references, 4 figures, 3 tables

  10. A prototype wearable tritium monitor

    International Nuclear Information System (INIS)

    Surette, R. A.; Dubeau, J.

    2008-01-01

    Sudden unexpected changes in tritium-in-air concentrations in workplace air can result in significant unplanned exposures. Although fixed area monitors are used to monitor areas where there is a potential for elevated tritium in air concentrations, they do not monitor personnel air space and may require some time for acute tritium releases to be detected. There is a need for a small instrument that will quickly alert staff of changing tritium hazards. A moderately sensitive tritium instrument that workers could wear would bring attention to any rise in tritium levels that were above predetermined limits and help in assessing the potential hazard therefore minimizing absorbed dose. Hand-held instruments currently available can be used but require the assistance of a fellow worker or restrict the user to using only one hand to perform some duties. (authors)

  11. Toxicity of tritium

    International Nuclear Information System (INIS)

    Dobson, R.L.

    1979-01-01

    Among radionuclides of importance in atomic energy, 3 H has relatively low toxicity. The main health and environmental worry is the possibility that significant biological effects may follow from protracted exposure to low concentrations in water. To examine this possible hazard and measure toxicity at low tritium concentrations, chronic exposure studies were done on mice and monkeys. During vulnerable developmental periods animals were exposed to 3 HOH, and mice were exposed also to 60 Co gamma irradiation and energy-related chemical agents. The biological endpoint measured was the irreversible loss of female germ cells. Effects from tritium were observed at surprisingly low concentrations where 3 H was found more damaging than previously thought. Comparisons between tritium and gamma radiation showed the relative biological effectiveness (RBE) to be greater than 1 and to reach approximately 3 at very low exposures. For perspective, other comparisons were made: between radiation and chemical agents, which revealed parallels in action on germ cells, and between pre- and postnatal exposure, which warn of possible special hazard to the fetus from both classes of energy-related byproducts

  12. Tritium inventory tracking and management

    International Nuclear Information System (INIS)

    Eichenberg, T.W.; Klein, A.C.

    1990-01-01

    This investigation has identified a number of useful applications of the analysis of the tracking and management of the tritium inventory in the various subsystems and components in a DT fusion reactor system. Due to the large amounts of tritium that will need to be circulated within such a plant, and the hazards of dealing with the tritium an electricity generating utility may not wish to also be in the tritium production and supply business on a full time basis. Possible scenarios for system operation have been presented, including options with zero net increase in tritium inventory, annual maintenance and blanket replacement, rapid increases in tritium creation for the production of additional tritium supplies for new plant startup, and failures in certain system components. It has been found that the value of the tritium breeding ratio required to stabilize the storage inventory depends strongly on the value and nature of other system characteristics. The real operation of a DT fusion reactor power plant will include maintenance and blanket replacement shutdowns which will affect the operation of the tritium handling system. It was also found that only modest increases in the tritium breeding ratio are needed in order to produce sufficient extra tritium for the startup of new reactors in less than two years. Thus, the continuous operation of a reactor system with a high tritium breeding ratio in order to have sufficient supplies for other plants is not necessary. Lastly, the overall operation and reliability of the power plant is greatly affected by failures in the fuel cleanup and plasma exhaust systems

  13. Tritium removal and retention device

    International Nuclear Information System (INIS)

    Boyle, R.F.; Durigon, D.D.

    1980-01-01

    A device is provided for removing and retaining tritium from a gaseous medium, and also a method of manufacturing the device. The device, consists of an inner core of zirconium alloy, preferably Zircaloy-4, and an outer adherent layer of nickel which acts as a selective and protective window for passage of tritium. The tritium then reacts with or is absorbed by the zirconium alloy, and is retained until such time as it is desirable to remove it during reprocessing. (auth)

  14. An overview of tritium production

    International Nuclear Information System (INIS)

    He Kaihui; Huang Jinghua; Feng Kaiming

    2002-01-01

    The characteristics of three types of proposed tritium production facilities, fissile type, accelerator production tritium (APT), and fusion type, are presented. The fissile reactors, especially commercial light water reactor, use comparatively mature technology and are designed to meet current safety and environmental guidelines. Conversely, APT shows many advantages except its rather high cost, while fusion reactors appear to offer improved safety and environmental impact, in particular, tritium production based on the fusion-based neutron source. However, its cost keeps unknown

  15. Tritium monitor and collection system

    Science.gov (United States)

    Bourne, G.L.; Meikrantz, D.H.; Ely, W.E.; Tuggle, D.G.; Grafwallner, E.G.; Wickham, K.L.; Maltrud, H.R.; Baker, J.D.

    1992-01-14

    This system measures tritium on-line and collects tritium from a flowing inert gas stream. It separates the tritium from other non-hydrogen isotope contaminating gases, whether radioactive or not. The collecting portion of the system is constructed of various zirconium alloys called getters. These alloys adsorb tritium in any of its forms at one temperature and at a higher temperature release it as a gas. The system consists of four on-line getters and heaters, two ion chamber detectors, two collection getters, and two guard getters. When the incoming gas stream is valved through the on-line getters, 99.9% of it is adsorbed and the remainder continues to the guard getter where traces of tritium not collected earlier are adsorbed. The inert gas stream then exits the system to the decay chamber. Once the on-line getter has collected tritium for a predetermined time, it is valved off and the next on-line getter is valved on. Simultaneously, the first getter is heated and a pure helium purge is employed to carry the tritium from the getter. The tritium loaded gas stream is then routed through an ion chamber which measures the tritium activity. The ion chamber effluent passes through a collection getter that readsorbs the tritium and is removable from the system once it is loaded and is then replaced with a clean getter. Prior to removal of the collection getter, the system switches to a parallel collection getter. The effluent from the collection getter passes through a guard getter to remove traces of tritium prior to exiting the system. The tritium loaded collection getter, once removed, is analyzed by liquid scintillation techniques. The entire sequence is under computer control except for the removal and analysis of the collection getter. 7 figs.

  16. Tritium-assisted fusion breeders

    International Nuclear Information System (INIS)

    Greenspan, E.; Miley, G.H.

    1983-08-01

    This report undertakes a preliminary assessment of the prospects of tritium-assisted D-D fuel cycle fusion breeders. Two well documented fusion power reactor designs - the STARFIRE (D-T fuel cycle) and the WILDCAT (Cat-D fuel cycle) tokamaks - are converted into fusion breeders by replacing the fusion electric blankets with 233 U producing fission suppressed blankets; changing the Cat-D fuel cycle mode of operation by one of the several tritium-assisted D-D-based modes of operation considered; adjusting the reactor power level; and modifying the resulting plant cost to account for the design changes. Three sources of tritium are considered for assisting the D-D fuel cycle: tritium produced in the blankets from lithium or from 3 He and tritium produced in the client fission reactors. The D-D-based fusion breeders using tritium assistance are found to be the most promising economically, especially the Tritium Catalyzed Deuterium mode of operation in which the 3 He exhausted from the plasma is converted, by neutron capture in the blanket, into tritium which is in turn fed back to the plasma. The number of fission reactors of equal thermal power supported by Tritium Catalyzed Deuterium fusion breeders is about 50% higher than that of D-T fusion breeders, and the profitability is found to be slightly lower than that of the D-T fusion breeders

  17. Tritium removal and retention device

    International Nuclear Information System (INIS)

    1976-01-01

    The patent discloses an apparatus comprising a two-layered composite with an internal core of zirconium or zirconium alloy which retains tritium, and an adherent nickel outer layer which acts as a protective and selective window for passage of the tritium. The invention provides a device to remove and store tritium from a gaseous medium as well as a method for manufacturing the device. It specifically provides a device which may be incorporated in the fuel rod of a nuclear reactor to minimize release of tritium to the reactor coolant

  18. Scoping Analyses on Tritium Permeation to VHTR Integarted Industrial Application Systems

    Energy Technology Data Exchange (ETDEWEB)

    Chang H. Oh; Eung S. Kim

    2011-03-01

    Tritium permeation is a very important current issue in the very high temperature reactor (VHTR) because tritium is easily permeated through high temperature metallic surfaces. Tritium permeations in the VHTR-integrated systems were investigated in this study using the tritium permeation analysis code (TPAC) that was developed by Idaho National Laboratory (INL). The INL TPAC is a numerical tool that is based on the mass balance equations of tritium containing species and hydrogen (i.e. HT, H2, HTO, HTSO4, TI) coupled with a variety of tritium sources, sink, and permeation models. In the TPAC, ternary fission and thermal neutron caption reactions with 6Li, 7Li 10B, 3He were taken into considerations as tritium sources. Purification and leakage models were implemented as main tritium sinks. Permeation of tritium and H2 through pipes, vessels, and heat exchangers were considered as main tritium transport paths. In addition, electroyzer and isotope exchange models were developed for analyzing hydrogen production systems including high temperature electrolysis (HTSE) and sulfur-iodine processes.

  19. Tritium source identification in CANDU reactors

    International Nuclear Information System (INIS)

    Allsop, P.J.; Aydogdu, K.; MacWilliams, R.; Miller, J.M.

    1997-06-01

    Very small amounts of tritiated heavy water may escape from the moderator and heat-transport systems of CANDU reactors during maintenance and normal operation. Through comprehensive tritium management, the impact of this leaked heavy water on operating personnel and the environment can be controlled. One useful management technique is source identification, a set of methods for locating very small heavy-water leaks. This technique permits an operator to optimize plant performance, adapting to changes in plant conditions. Various identification methods are available, including local-hazard monitoring, tritium mapping and the correlation of measured hazards with emissions and hazards in other areas. The suitability of each method depends on the management objectives. In this report, each of these methods is reviewed and applications discussed. (author)

  20. JET experiments with tritium and deuterium–tritium mixtures

    NARCIS (Netherlands)

    Horton, L.; Batistoni, P.; Boyer, H.; Challis, C.; Ciric, D.; Donne, A. J. H.; Eriksson, L. G.; Garcia, J.; Garzotti, L.; Gee, S.; Hobirk, J.; Joffrin, E.; Jones, T.; King, D. B.; Knipe, S.; Litaudon, X.; Matthews, G. F.; Monakhov, I.; Murari, A.; Nunes, I.; Riccardo, V.; Sips, A. C. C.; Warren, R.; Weisen, H.; Zastrow, K. D.

    2016-01-01

    Extensive preparations are now underway for an experiment in the Joint European Torus (JET) using tritium and deuterium–tritium mixtures. The goals of this experiment are described as well as the progress that has been made in developing plasma operational scenarios and physics reference pulses for

  1. The impact of transportation and translocation on dispersal behaviour in the invasive cane toad.

    Science.gov (United States)

    Pettit, Lachlan; Greenlees, Matthew; Shine, Richard

    2017-06-01

    Biological invasions transport organisms to novel environments; but how does the translocation process influence movement patterns of the invader? Plausibly, the stress of encountering a novel environment, or of the transport process, might induce rapid dispersal from the release site-potentially enhancing (or reducing) invader success and spread. We investigated the effect of transportation and release to novel environments on dispersal-relevant traits of one of the world's most notorious invaders, the cane toad (Rhinella marina). We collected toads in northern New South Wales from heath and woodland habitats, manipulated the level of transport stress and either returned toads to their exact collection point (residents) or reciprocally translocated them to a novel site. Both translocation and the level of transport stress drastically altered toad dispersal rates for at least 5 days post-release. Translocated toads (depending on their level of transport stress and release habitat) moved on average two to five times further per day (mean range 67-148 m) than did residents (mean range 22-34 m). Translocated toads also moved on more days, and moved further from their release point than did resident toads, but did not move in straighter lines. A higher level of transport stress (simulating long-distance translocation) had no significant effect on movements of resident toads but amplified the dispersal of translocated toads only when released into woodland habitat. These behavioural shifts induced by translocation and transportation may affect an invader's ability to colonise novel sites, and need to be incorporated into plans for invader control.

  2. Tritium contaminated waste management at the tritium systems test assembly

    International Nuclear Information System (INIS)

    Jalbert, R.A.; Carlson, R.V.

    1987-01-01

    The Tritium Systems Test Assembly (TSTA) at Los Alamos continues to move toward full operation of an integrated, full-sized, computer-controlled fusion fuel processing loop. Concurrent nonloop experiments further the development of advanced tritium technologies and handling methods. Since tritium operations began in June 1984, tritium contaminated wastes have been produced at TSTA that are roughly typical in kind and amount of those to be produced by tritium fueling operations at fusion reactors. Methods of managing these wastes are described, including information on some methods of decontamination so that equipment can be reused. Data are given on the kinds and amounts of wastes and the general level of contamination. Also included are data on environmental emissions and doses to personnel that have resulted from TSTA operations. Particular problems in waste managements are discussed

  3. 2009 EVALUATION OF TRITIUM REMOVAL AND MITIGATION TECHNOLOGIES FOR WASTEWATER TREATMENT

    Energy Technology Data Exchange (ETDEWEB)

    LUECK KJ; GENESSE DJ; STEGEN GE

    2009-02-26

    atmosphere, and (4) use of barriers to minimize the transport of tritium in groundwater. Continuing development efforts for tritium separations processes are primarily to support the International Thermonuclear Experimental Reactor (ITER) program, the nuclear power industry, and the production of radiochemicals. While these applications are significantly different than the Hanford application, the technology could potentially be adapted for Hanford wastewater treatment. Separations based processes to reduce tritium levels below the drinking water MCL have not been demonstrated for the scale and conditions required for treating Hanford wastewater. In addition, available cost information indicates treatment costs for such processes will be substantially higher than for discharge to SALDS or other typical pump and treat projects at Hanford. Actual mitigation projects for groundwater with very low tritium contamination similar to that found at Hanford have focused mainly on controlling migration and on evaporation for dispersion in the atmosphere.

  4. Problematics due to tritium in materials in the nuclear field - some examples; Problematiques liees au tritium dans les materiaux dans le domaine nucleaire - quelques illustrations

    Energy Technology Data Exchange (ETDEWEB)

    Gastaldi, O. [CEA Cadarache (DEN/DTN/STPA/LPC), 13 - Saint-Paul-lez-Durance (France)

    2007-07-01

    After a presentation of the tritium sources in our environment, is evoked succinctly the different ways to produce it. Then, for each reactor type, are presented the main problematics due to tritium. In this part, the questions of tritium transfer are illustrated for fission reactors: pressurized water reactors, CANDU reactors and for fast neutrons reactors. The case of fusion tokamaks is described more particularly. Several aspects are presented successively: the requirement to produce it in-situ with fitted materials, the definition of a short fuel cycle allowing to recover important quantities of tritium having not react...In a last part, are presented the aspects directly induced by the behaviour of tritium in materials. The first point concerned is the control of the tritium inventory in a fusion tokamak, for safety reasons. Examples are given from experiment feedback on running fusion tokamaks. A projection at the ITER case is proposed. The mechanisms leading to tritium retention according to the materials considered at the present time are analyzed and synthesized. The second important point is the tritium management at the end of the tokamak running. The specific problematics of this management are presented. (O.M.)

  5. Effect of hydrophobic paints coating for tritium reduction in concrete materials

    International Nuclear Information System (INIS)

    Edao, Y.; Fukada, S.; Nishimura, Y.; Katayama, K.; Takeishi, T.; Hatano, Y.; Taguchi, A.

    2012-01-01

    Highlights: ► Effects of hydrophobic paint coating in tritium transport are investigated. ► Two kinds of paints, acrylic-silicon resin and epoxy resin are used. ► The hydrophobic paints are effective to reduce tritium permeation. ► The effect of tritium reduction of epoxy paint is higher than that of silicon. - Abstract: The effects of hydrophobic paint coating on a concrete material of cement paste on the tritium transport are investigated. The cement paste is coated with two kinds of paints, acrylic-silicon resin paint and epoxy resin paint. We investigated the amount of tritium trapped in the samples exposed to tritiated water vapor by means of sorption and release. It was found that both the hydrophobic paints could reduce effectively tritium permeation during 50 days exposure of tritiated water vapor. The effect of tritium reduction of the epoxy paint was higher than that of silicon while the amount of tritium trapped in the epoxy paint was larger than that of silicon due to difference of the structure. Based on an analysis of a diffusion model, the rate-determining step of tritium migration through cement paste coated with the paints is diffusion through the paints respectively. It was found that tritium was easy to penetrate through silicon because there were many pores or voids in the silicon comparatively. In the case of tritium released from the epoxy paint, it is considered that tritium diffusion in epoxy is slow due to retardation by isotope exchange reaction to water included in epoxy paint.

  6. Aquatic dispersion modelling of a tritium plume in Lake Ontario

    International Nuclear Information System (INIS)

    Klukas, M.H.; Moltyaner, G.L.

    1996-05-01

    Approximately 2900 kg of tritiated water, containing 2.3E+15 Bq of tritium, were released to Lake Ontario via the cooling water discharge when a leak developed in a moderator heat exchanger in Unit 1 at the Pickering Nuclear Generating Station (PNGS) on 1992 August 2. The release provided the opportunity to study the dispersion of a tritium plume in the coastal zone of Lake Ontario. Current direction over the two-week period following the release was predominantly parallel to the shore, and elevated tritium concentrations were observed up to 20 km east and 85 km west of the PNGS. Predictions of the tritium plume movement were made using current velocity measurements taken at 8-m depth, 2.5 km offshore from Darlington and using a empirical relationship where alongshore current speed is assumed to be proportional to the alongshore component of the wind speed. The tritium migration was best described using current velocity measurements. The tritium plume dispersion is modelled using the one-dimensional advection-dispersion equation. Transport parameters are the alongshore current speed and longitudinal dispersion coefficient. Longitudinal dispersion coefficients, estimated by fitting the solution of the advection-dispersion equation to measured concentration distance profiles ranged from 3.75 to 10.57 m 2 s -1 . Simulations using the fitted values of the dispersion coefficient were able to describe maximum tritium concentrations measured at water supply plants located within 25 km of Pickering to within a factor of 3. The dispersion coefficient is a function of spatial and temporal variability in current velocity and the fitted dispersion coefficients estimated here may not be suitable for predicting tritium plume dispersion under different current conditions. The sensitivity of the dispersion coefficient to variability in current conditions should be evaluated in further field experiments. (author). 13 refs., 7 tabs., 12 figs

  7. Developing a long-term global tourism transport model using a behavioural approach: implications for sustainable tourism policy making.

    NARCIS (Netherlands)

    Peeters, P.M.

    2013-01-01

    This paper explores the creation and use of a long-term global tourism transport model for private and public sector tourism policy makers. Given that technology is unlikely to reduce tourism transport's impact on climate change sufficiently to avoid serious dangers, behavioural change is necessary.

  8. Ontario Hydro diversifies into tritium

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    A report is given on a plant which is to be built at the Darlington Candu reactor site in Canada for the extraction of tritium from heavy water. As tritium is used as a fuel in fusion research the market for it is expected to grow. The design of the system is outlined with the help of a flow diagram. (U.K.)

  9. The tritium operations experience on TFTR

    Energy Technology Data Exchange (ETDEWEB)

    von Halle, A.; Gentile, C. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Anderson, J.L. [Los Alamos National Lab., NM (United States)] [and others

    1994-09-01

    The Tokamak Fusion Test Reactor (TFTR) tritium gas system is administratively limited to 5 grains of tritium and provides the feedstock gas for the neutral beam and torus injection systems. Tritium operations on TFTR began with leak checking of gas handling systems, qualification of the gas injection systems, and high power plasma operations using using trace amounts of tritium in deuterium feedstock gas. Full tritium operation commenced with four highly diagnosed neutral beam pulses into a beamline calorimeter to verify planned tritium beam operating routines and to demonstrate the deuterium to tritium beam isotope exchange. Since that time, TFTR has successfully operated each of the twelve neutral beam ion sources in tritium during hundreds of tritium beam pulses and torus gas injections. This paper describes- the TFTR tritium gas handling systems and TFTR tritium operations of the gas injection systems and the neutral beam ion sources. Tritium accounting and accountability is discussed, including tritium retention issues of the torus limiters and beam impinged surfaces of the beamline components. Also included is tritium beam velocity analysis that compares the neutral beam extracted ion species composition for deuterium and tritium and that determines the extent of beam isotope exchange on subsequent deuterium and tritium beam pulses. The required modifications to TFTR operating routines to meet the US Department of Energy regulations for a low hazard nuclear facility and the problems encountered during initial tritium operations are described.

  10. Tritium practices past and present

    International Nuclear Information System (INIS)

    Gede, V.P.; Gildea, P.D.

    1980-01-01

    History of the production and use of tritium, as well as handling techniques, are reviewed. Handling techniques first used at Lawrence Livermore National Laboratory made use of glass vacuum systems and relatively crude ion chambers for monitoring airborne activity. The first use of inert atmosphere glove boxes demonstrated that uptake through the skin could be a serious personnel exposure problem. Growing environmental concerns in the early 1970's resulted in the implementation by the Atomic Energy Commission of a new criteria to limit atmospheric tritium releases to levels as low as practicable. An important result of the new criteria was the development of containment and recovery systems to capture tritium rather than vent it to the atmosphere. The Sandia National Laboratories, Livermore, Tritium Research Laboratory containment and decontamination systems are presented as a typical example of this technology. The application of computers to control systems is expected to provide the greatest potential for change in future tritium handling practices

  11. Tritium metabolism in rat tissues

    International Nuclear Information System (INIS)

    Takeda, H.

    1982-01-01

    As part of a series of studies designed to evaluate the relative radiotoxicity of various tritiated compounds, metabolism of tritium in rat tissues was studied after administration of tritiated water, leucine, thymidine, and glucose. The distribution and retention of tritium varied widely, depending on the chemical compound administered. Tritium introduced as tritiated water behaved essentially as body water and became uniformly distributed among the tissues. However, tritium administered as organic compounds resulted in relatively high incorporation into tissue constituents other than water, and its distribution differed among the various tissues. Moreover, the excretion rate of tritium from tissues was slower for tritiated organic compounds than for tritiated water. Administrationof tritiated organic compounds results in higher radiation doses to the tissues than does administration of tritiated water. Among the tritiated compounds examined, for equal radioactivity administered, leucine gave the highest radiation dose, followed in turn by thymidine, glucose, and water. (author)

  12. Reliability and validity of the transport and physical activity questionnaire (TPAQ) for assessing physical activity behaviour.

    Science.gov (United States)

    Adams, Emma J; Goad, Mary; Sahlqvist, Shannon; Bull, Fiona C; Cooper, Ashley R; Ogilvie, David

    2014-01-01

    No current validated survey instrument allows a comprehensive assessment of both physical activity and travel behaviours for use in interdisciplinary research on walking and cycling. This study reports on the test-retest reliability and validity of physical activity measures in the transport and physical activity questionnaire (TPAQ). The TPAQ assesses time spent in different domains of physical activity and using different modes of transport for five journey purposes. Test-retest reliability of eight physical activity summary variables was assessed using intra-class correlation coefficients (ICC) and Kappa scores for continuous and categorical variables respectively. In a separate study, the validity of three survey-reported physical activity summary variables was assessed by computing Spearman correlation coefficients using accelerometer-derived reference measures. The Bland-Altman technique was used to determine the absolute validity of survey-reported time spent in moderate-to-vigorous physical activity (MVPA). In the reliability study, ICC for time spent in different domains of physical activity ranged from fair to substantial for walking for transport (ICC = 0.59), cycling for transport (ICC = 0.61), walking for recreation (ICC = 0.48), cycling for recreation (ICC = 0.35), moderate leisure-time physical activity (ICC = 0.47), vigorous leisure-time physical activity (ICC = 0.63), and total physical activity (ICC = 0.56). The proportion of participants estimated to meet physical activity guidelines showed acceptable reliability (k = 0.60). In the validity study, comparison of survey-reported and accelerometer-derived time spent in physical activity showed strong agreement for vigorous physical activity (r = 0.72, ptravel behaviours and may be suitable for wider use. Its physical activity summary measures have comparable reliability and validity to those of similar existing questionnaires.

  13. How to minimise the incidence of transport-related problem behaviours in horses: a review.

    Science.gov (United States)

    York, Amanda; Matusiewicz, Judith; Padalino, Barbara

    2017-01-01

    This review aims to provide practical outcomes on how to minimise the incidence of transport-related problem behaviours (TRPBs) in horses. TRPBs are unwanted behaviours occurring during different phases of transport, most commonly, a reluctance to load and scrambling during travelling. TRPBs can result in injuries to horses and horse handlers, horse trailer accidents, disruption of time schedules, inability to attend competitions, and poor performance following travel. Therefore, TRPBs are recognised as both a horse-related risk to humans and a human-related risk to horses. From the literature, it is apparent that TRPBs are common throughout the entire equine industry, and a YouTube keyword search of 'horse trailer loading' produced over 67,000 results, demonstrating considerable interest in this topic and the variety of solutions suggested. Drawing upon articles published over the last 35 years, this review summarises current knowledge on TRPBs and provides recommendations on their identification, management, and prevention. It appears that a positive human-horse relationship, in-hand pre-training, systematic training for loading and travelling, appropriate horse handling, and the vehicle driving skills of the transporters are crucial to minimise the incidence of TRPBs. In-hand pre-training based on correct application of the principles of learning for horses and horse handlers, habituation to loading and travelling, and self-loading appear to minimise the risk of TRPBs and are therefore strongly recommended to safeguard horse and horse-handler health and welfare. This review indicates that further research and education with respect to transport management are essential to substantially decrease the incidence of TRPBs in horses.

  14. Tritium-surface interactions

    International Nuclear Information System (INIS)

    Kirkaldy, J.S.

    1983-06-01

    The report deals broadly with tritium-surface interactions as they relate to a fusion power reactor enterprise, viz., the vacuum chamber, first wall, peripherals, pumping, fuel recycling, isotope separation, repair and maintenance, decontamination and safety. The main emphasis is on plasma-surface interactions and the selection of materials for fusion chamber duty. A comprehensive review of the international (particularly U.S.) research and development is presented based upon a literature review (about 1 000 reports and papers) and upon visits to key laboratories, Sandia, Albuquerque, Sandia, Livermore and EGβG Idaho. An inventory of Canadian expertise and facilities for RβD on tritium-surface interactions is also presented. A number of proposals are made for the direction of an optimal Canadian RβD program, emphasizing the importance of building on strength in both the technological and fundamental areas. A compendium of specific projects and project areas is presented dealing primarily with plasma-wall interactions and permeation, anti-permeation materials and surfaces and health, safety and environmental considerations. Potential areas of industrial spinoff are identified

  15. Tritium-fueled betacells

    International Nuclear Information System (INIS)

    Walko, R.J.; Lincoln, R.C.; Baca, W.E.; Goods, S.H.; Negley, G.H.

    1991-01-01

    Betavoltaic power sources operate by converting the nuclear decay energy of beta-emitting radioisotopes into electricity. Since they are not chemically driven, they could operate at temperatures which would either be too hot or too cold for typical chemical batteries. Further, for long lived isotopes, they offer the possibility of multi-decade active lifetimes. In this paper two approaches are investigated: direct and indirect conversion. Direct conversion cells consist of semiconductor diodes similar to photovoltaic cells. Beta particles directly bombard these cells, generating electron-hole pairs in the semiconductor which are converted to useful power. When using low power flux beta emitters, wide bandgap semiconductors are required to achieve useful power. When using low power flux beta emitters, wide bandgap semiconductors are required to achieve useful conversion efficiencies. The combination of tritium, as the beta emitter, and gallium phosphide (GaP), as the semiconductor converter, was evaluated. Indirect conversion betacells first convert the beta energy to light with a phosphor, and then to electricity with photovoltaic cells. An indirect conversion power source using a tritium radioluminescent (RL) light is being investigated. The authors analysis indicates that this approach has the potential for significant volume and cost savings over the direct conversion method

  16. Surface effects on tritium diffusion in materials in a radiation environment

    International Nuclear Information System (INIS)

    Caskey, G.R. Jr.

    1975-01-01

    Tritium transport and distribution in a material are controlled by chemical potential and thermal gradients and cross-coupling to impurities and defects. Surfaces influence tritium diffusion by acting as sources and sinks for defects and impurities, and surface films restricting tritium transfer between the solid and surrounding fluids. Radiation directly affects boundary processes such as dissociation or adsorption, may erode a surface film or the surface itself, and introduces defects and impurities into the solid by radiation damage, transmutation, or ion implantation, thereby modifying tritium transport within the solid and its transfer across external interfaces. There have been no definitive investigations of these effects, but their practical significance has been demonstrated in tritium release or absorption studies with stainless steel, Zircaloy, niobium, and other materials. (auth)

  17. Modeling of the geochemical behaviour and of the radionuclide transport in the presence of colloids

    International Nuclear Information System (INIS)

    Van der Lee, Jan

    1997-01-01

    Over the past ten years, colloids have been introduced in the already complex subject of waste storage safety analysis. They are indeed often considered as rapid carriers for otherwise insoluble radioactive elements, and therefore potentially decrease the effective barrier function of the geological rock surrounding the waste. The problem is therefore to understand colloid behaviour and quantify their stability and reactivity with respect to the radionuclides. The subject reveals three different levels of phenomena: the geochemical mechanisms, the micro-physical and electrostatic behaviour of colloids and the transport mechanisms. The topics of this thesis therefore cover a wide range of disciplines, such as geochemistry, radiochemistry, physics, hydrogeology, mathematics and computer science. Given the complexity of the subject, only strongly simplified models are used for safety assessment including the impact of colloids. Henceforth, the objective of this study is to provide a comprehensive theoretical basis for modelling the impact of colloids according to a deterministic approach, in the hope to pave the road towards predictive modelling of a waste repository performance. This thesis is the result of work carried out in different European Community projects in the framework of the fourth R and D program on 'Management and Storage of Radioactive Waste'. part A, task 4, 'Disposal of Radioactive Waste'. Grateful use has been made of many chemical and hydrogeological experiments carried out by many different laboratories all over Europe. The main results can be classified according to three principal topics: - geochemistry and the chemical behaviour of actinides, lanthanides and fission products; - retention mechanisms of colloidal particles; - transport mechanism in geological medium. The first topic is fundamental: geochemistry forms the basis of e.g. the retention model for aqueous and colloidal species. The principal result of this topic is

  18. Commissioning of a DT fusion reactor without external supply of tritium

    International Nuclear Information System (INIS)

    Asaoka, Y.; Konishi, S.; Nishio, S.; Hiwatari, R.; Okano, K.; Yoshida, T.; Tomabechi, K.

    2001-01-01

    Commissioning of a DT fusion reactor without external supply of tritium is discussed. The DD reactions in a DT-oriented fusion reactor with external power injection by neutral beams produce tritium and neutrons. Tritium produced by the DD reaction together with that produced in the blanket by the 2.45 MeV neutron is re-circulated into the plasma. Then, the DT reaction rate increases gradually, as tritium concentration in plasma builds up towards the level of nominal operation. Time required to reach the nominal operational condition, i.e. 50 % tritium in plasma, is estimated with assumptions based on a model of fusion power plant. As a result, the start-up period of a DT fusion reactor without external supply of tritium is estimated to be approximately 55 days, with the plasma parameters of CREST having a high performance blanket and tritium processing systems. Major factors to determine the start-up period are DD and DT reaction rates, net tritium breeding gain of the plant and dead inventory in/on facing materials. Elimination of a constraint for fusion reactor deployment and operation without any tritium transportation in and out of plant through its entire life may be possible. (author)

  19. Commercial Light Water Reactor -Tritium Extraction Facility Process Waste Assessment (Project S-6091)

    International Nuclear Information System (INIS)

    Hsu, R.H.; Delley, A.O.; Alexander, G.J.; Clark, E.A.; Holder, J.S.; Lutz, R.N.; Malstrom, R.A.; Nobles, B.R.; Carson, S.D.; Peterson, P.K.

    1997-01-01

    The Savannah River Site (SRS) has been tasked by the Department of Energy (DOE) to design and construct a Tritium Extraction Facility (TEF) to process irradiated tritium producing burnable absorber rods (TPBARs) from a Commercial Light Water Reactor (CLWR). The plan is for the CLWR-TEF to provide tritium to the SRS Replacement Tritium Facility (RTF) in Building 233-H in support of DOE requirements. The CLWR-TEF is being designed to provide 3 kg of new tritium per year, from TPBARS and other sources of tritium (Ref. 1-4).The CLWR TPBAR concept is being developed by Pacific Northwest National Laboratory (PNNL). The TPBAR assemblies will be irradiated in a Commercial Utility light water nuclear reactor and transported to the SRS for tritium extraction and processing at the CLWR-TEF. A Conceptual Design Report for the CLWR-TEF Project was issued in July 1997 (Ref. 4).The scope of this Process Waste Assessment (PWA) will be limited to CLWR-TEF processing of CLWR irradiated TPBARs. Although the CLWR- TEF will also be designed to extract APT tritium-containing materials, they will be excluded at this time to facilitate timely development of this PWA. As with any process, CLWR-TEF waste stream characteristics will depend on process feedstock and contaminant sources. If irradiated APT tritium-containing materials are to be processed in the CLWR-TEF, this PWA should be revised to reflect the introduction of this contaminant source term

  20. Commercial Light Water Reactor -Tritium Extraction Facility Process Waste Assessment (Project S-6091)

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, R.H.; Delley, A.O.; Alexander, G.J.; Clark, E.A.; Holder, J.S.; Lutz, R.N.; Malstrom, R.A.; Nobles, B.R. [Westinghouse Savannah River Co., Aiken, SC (United States); Carson, S.D. [Sandia National Laboratories, New Mexico, NM (United States); Peterson, P.K. [Sandia National Laboratories, New Mexico, NM (United States)

    1997-11-30

    The Savannah River Site (SRS) has been tasked by the Department of Energy (DOE) to design and construct a Tritium Extraction Facility (TEF) to process irradiated tritium producing burnable absorber rods (TPBARs) from a Commercial Light Water Reactor (CLWR). The plan is for the CLWR-TEF to provide tritium to the SRS Replacement Tritium Facility (RTF) in Building 233-H in support of DOE requirements. The CLWR-TEF is being designed to provide 3 kg of new tritium per year, from TPBARS and other sources of tritium (Ref. 1-4).The CLWR TPBAR concept is being developed by Pacific Northwest National Laboratory (PNNL). The TPBAR assemblies will be irradiated in a Commercial Utility light water nuclear reactor and transported to the SRS for tritium extraction and processing at the CLWR-TEF. A Conceptual Design Report for the CLWR-TEF Project was issued in July 1997 (Ref. 4).The scope of this Process Waste Assessment (PWA) will be limited to CLWR-TEF processing of CLWR irradiated TPBARs. Although the CLWR- TEF will also be designed to extract APT tritium-containing materials, they will be excluded at this time to facilitate timely development of this PWA. As with any process, CLWR-TEF waste stream characteristics will depend on process feedstock and contaminant sources. If irradiated APT tritium-containing materials are to be processed in the CLWR-TEF, this PWA should be revised to reflect the introduction of this contaminant source term.

  1. Protective Behaviour of Citizens to Transport Accidents Involving Hazardous Materials: A Discrete Choice Experiment Applied to Populated Areas nearby Waterways.

    Science.gov (United States)

    de Bekker-Grob, Esther W; Bergstra, Arnold D; Bliemer, Michiel C J; Trijssenaar-Buhre, Inge J M; Burdorf, Alex

    2015-01-01

    To improve the information for and preparation of citizens at risk to hazardous material transport accidents, a first important step is to determine how different characteristics of hazardous material transport accidents will influence citizens' protective behaviour. However, quantitative studies investigating citizens' protective behaviour in case of hazardous material transport accidents are scarce. A discrete choice experiment was conducted among subjects (19-64 years) living in the direct vicinity of a large waterway. Scenarios were described by three transport accident characteristics: odour perception, smoke/vapour perception, and the proportion of people in the environment that were leaving at their own discretion. Subjects were asked to consider each scenario as realistic and to choose the alternative that was most appealing to them: staying, seeking shelter, or escaping. A panel error component model was used to quantify how different transport accident characteristics influenced subjects' protective behaviour. The response was 44% (881/1,994). The predicted probability that a subject would stay ranged from 1% in case of a severe looking accident till 62% in case of a mild looking accident. All three transport accident characteristics proved to influence protective behaviour. Particularly a perception of strong ammonia or mercaptan odours and visible smoke/vapour close to citizens had the strongest positive influence on escaping. In general, 'escaping' was more preferred than 'seeking shelter', although stated preference heterogeneity among subjects for these protective behaviour options was substantial. Males were less willing to seek shelter than females, whereas elderly people were more willing to escape than younger people. Various characteristics of transport accident involving hazardous materials influence subjects' protective behaviour. The preference heterogeneity shows that information needs to be targeted differently depending on gender and age

  2. Overview of the tritium system of Ignitor

    International Nuclear Information System (INIS)

    Rizzello, C.; Tosti, S.

    2008-01-01

    Among the recent design activities of the Ignitor program, the analysis of the tritium system has been carried out with the aim to describe the main equipments and the operations needed for supplying the deuterium-tritium mixtures and recovering the plasma exhaust. In fact, the tritium system of Ignitor provides for injecting deuterium-tritium mixtures into the vacuum chamber in order to sustain the fusion reaction: furthermore, it generally manages and controls the tritium and the tritiated materials of the machine fuel cycle. Main functions consist of tritium storage and delivery, tritium injection, tritium recovery from plasma exhaust, treatment of the tritiated wastes, detritiation of the contaminated atmospheres, tritium analysis and accountability. In this work an analysis of the designed tritium system of Ignitor is summarized

  3. Tritium handling experience at TFTR

    International Nuclear Information System (INIS)

    Anderson, J.L.; Gentile, C.; Hosea, J.

    1994-01-01

    In December 1993 the high power D-T experimental program on the Tokamak Fusion Test Reactor (TFTR) began. The transit the TFTR from a DOE general use facility to a low hazard category III nuclear facility has been completed successfully. The low hazard nuclear facility designation that the allowable on-site tritium inventory not exceed 50,000 Curies (1 Ci = 37 GBq). This is a TFTR Technical Safety Requirement. Tritium sealed in approved shipping containers does riot count against this inventory limit A second Technical Safety Requirement at TFTR is to have no more than 25,000 Ci at risk in a single location. From December, 1993 through mid-August, 1994 about 20 grams of tritium have been used in two gas injector assemblies and twelve neutral beam tritium injectors. The gas injected into TFTR vacuum is pumped by helium cryo-panels in the four neutral beam boxes. During non-operating periods the cryo-panels are warmed and the hydrogen am released and pumped into gas holding tanks in the tritium area. Gas in the holding tanks is oxidized in the Torus Cleanup System (TCS) and the hydrogen isotopes are collected, as water, on disposable molecular sieve beds (DMSB). These beds are then removed from the system and shipped off-site for tritium recovery or for long-term storage. Several problems in the tritium cleanup systems have occurred following a leak of sulfur hexafluoride (SF 6 ) from a neutral hewn high voltage enclosure ion source and subsequent pumping to the gas holding tanks. These problems included failure of several-moisture sensors, false readings on tritium monitors and, partial loss of catalytic activity in the TCS recombiner. Procedures for dealing with and removing this contaminant gas had to be developed and implemented. The results from this occurrence provide valuable guidance for future tritium burning fusion machines

  4. Shippers’ Choice Behaviour in Choosing Transport Mode: The Case of South East Asia (SEA Region

    Directory of Open Access Journals (Sweden)

    Chia-Hsun Chang

    2017-12-01

    Full Text Available Using South East Asia as a case study, shippers’ choice of transport modes taking into consideration their economic and environmental impacts was examined in this research. A triangulation of both quantitative and qualitative methods was deployed. First, a quantitative analysis using secondary data was conducted to establish the index score, which includes four quantitative factors (transport distance, cost, time, and CO2 emission, for each transport mode. In addition, in order to examine at what level of the importance weight shippers would change their decision on transport mode, a sensitivity analysis involving the four aforesaid factors was also conducted. Next, an in-depth interview with a major shipper in Singapore was also carried out to qualitatively validate the aforesaid four quantitative factors as well as two additional qualitative factors, namely, customer service and shipper-forwarder relationship in relation to shipper's choice. The results from this study indicate that shippers might change to the short-sea shipping (SSS mode when the importance weights of cost and CO2 emission increase, and to trucking mode when the weight of time decreases. It was also found that cost is the most important factor when shippers choose carriers/forwarders, whereas CO2 emission is not an important factor at the current stage. However, if the government imposes financial measures such as fine and/or tax for CO2 emission, shippers would choose eco-friendlier transport modes. This research is the first study considering the environmental issue as one of important factors that influence shippers’ choice behaviour. This research also facilitates managers’ understanding on how shippers may select LSPs taking into account important factors including the environmental consideration.

  5. Tritium, biography of an element

    International Nuclear Information System (INIS)

    Keller, C.

    1980-01-01

    Tritium is the lightest radioactive atom, an isotope of hydrogen. In science it has many uses, particularly for marking organic molecules in order to find out about biochemical and medical processes. But also the traces of tritium contained in rain or sea water are used for investigations; they range from establishing the vintage of old wines to ascertaining sea water mixtures. Tritium will become important in large-scale technology if it should become possible to construct fusion reactors, since it is one of the fuels. (orig.) [de

  6. The organically bound tritium: an analyst vision

    International Nuclear Information System (INIS)

    Ansoborlo, E.; Baglan, N.

    2009-01-01

    The authors report the work of a work group on tritium analysis. They recall the different physical forms of tritium: gas (HT, hydrogen-tritium), water vapour (HTO or tritiated water) or methane (CH3T), but also in organic compounds (OBT, organically bound tritium) which are either exchangeable or non-exchangeable. They evoke measurement techniques and methods, notably to determine the tritium volume activity. They discuss the possibilities to analyse and distinguish exchangeable and non-exchangeable OBTs

  7. Recovery of tritium from CANDU reactors, its storage and monitoring of its migration in the environment

    International Nuclear Information System (INIS)

    Holtslander, W.J.; Osborne, R.V.

    1979-07-01

    Tritium is produced in CANDU heavy water reactors mainly by neutron activation of deuterium. The typical production rate is 2.4 kCi per megawatt-year (89 TBq. per megawatt-year. In Pickering Generating Station the average concentration of tritium in the moderators has reached 16 Ci.kg -1 (0.6 TBq.kg -1 ) and in coolants, 0.5 Ci.kg -1 (0.02 TBq.kg -1 ). Concentrations will continue to increase towards an equilibrium determined by the production rate, the tritium decay rate and heavy water replacement. Tritium removal methods that are being considered for a pilot plant design are catalytic exchange of DTO with D 2 and electrolysis of D 2 O/DTO to provide feed for cryogenic distillation of D 2 /DT/T 2 . Storage methods for the removed tritium - as elemental gas, as metal hydrides and in cements - are also being investigated. Transport of tritiated wastes should not be a particularly difficult problem in light of extensive experience in transporting tritiated heavy water. Methods for determining the presence of tritium in the environment of any tritium handling facility are well established and have the capability of measuring concentrations of tritium down to current ambient values. (author)

  8. Tritium containment of controlled thermonuclear fusion reactor

    International Nuclear Information System (INIS)

    Tanaka, Yoshihisa; Tsukumo, Kiyohiko; Suzuki, Tatsushi

    1979-01-01

    It is well known that tritium is used as the fuel for nuclear fusion reactors. The neutrons produced by the nuclear fusion reaction of deuterium and tritium react with lithium in blankets, and tritium is produced. The blankets reproduce the tritium consumed in the D-T reaction. Tritium circulates through the main cooling system and the fuel supply and evacuation system, and is accumulated. Tritium is a radioactive substance emitting β-ray with 12.6 year half-life, and harmful to human bodies. It is an isotope of hydrogen, and apt to diffuse and leak. Especially at high temperature, it permeates through materials, therefore it is important to evaluate the release of tritium into environment, to treat leaked tritium to reduce its release, and to select the method of containing tritium. The permeability of tritium and its solubility in structural materials are discussed. The typical blanket-cooling systems of nuclear fusion reactors are shown, and the tungsten coating of steam generator tubes and tritium recovery system are adopted for reducing tritium leak. In case of the Tokamak type reactor of JAERI, the tritium recovery system is installed, in which the tritium gas produced in blankets is converted to tritium steam with a Pd-Pt catalytic oxidation tower, and it is dehydrated and eliminated with a molecular sieve tower, then purified and recovered. (Kako, I.)

  9. An investigation of tritium transfer in reactor loops

    Science.gov (United States)

    Ilyasova, O. H.; Mosunova, N. A.

    2017-09-01

    The work is devoted to the important task of the numerical simulation and analysis of the tritium behaviour in the reactor loops. The simulation was carried out by HYDRA-IBRAE/LM code, which is being developed in Nuclear safety institute of the Russian Academy of Sciences. The code is intended for modeling of the liquid metal flow (sodium, lead and lead-bismuth) on the base of non-homogeneous and non-equilibrium two-fluid model. In order to simulate tritium transfer in the code, the special module has been developed. Module includes the models describing the main phenomena of tritium behaviour in reactor loops: transfer, permeation, leakage, etc. Because of shortage of the experimental data, a lot of analytical tests and comparative calculations were considered. Some of them are presented in this work. The comparison of estimation results and experimental and analytical data demonstrate not only qualitative but also good quantitative agreement. It is possible to confirm that HYDRA-IBRAE/LM code allows modeling tritium transfer in reactor loops.

  10. TFTR tritium inventory accountability system

    International Nuclear Information System (INIS)

    Saville, C.; Ascione, G.; Elwood, S.; Nagy, A.; Raftopoulos, S.; Rossmassler, R.; Stencel, J.; Voorhees, D.; Tilson, C.

    1995-01-01

    This paper discusses the program, PPPL (Princeton Plasma Physics Laboratory) Material Control and Accountability Plan, that has been implemented to track US Department of Energy's tritium and all other accountable source material. Specifically, this paper details the methods used to measure tritium in various systems at the Tokamak Fusion Test Reactor; resolve inventory differences; perform inventory by difference inside the Tokamak; process and measure plasma exhaust and other effluent gas streams; process, measure and ship scrap or waste tritium on molecular sieve beds; and detail organizational structure of the Material Control and Accountability group. In addition, this paper describes a Unix-based computerized software system developed at PPPL to account for all tritium movements throughout the facility. 5 refs., 2 figs

  11. Tritium management for fusion reactors

    International Nuclear Information System (INIS)

    Rouyer, J.L.; Djerassi, H.

    1985-01-01

    To determine a waste management strategy, one has to identify first the wastes (quantities, activities, etc.), then to define options, and to compare these options by appropriate criteria and evaluations. Two European Associations are working together, i.e., Studsvik and CEA, on waste treatment and tritium problems. A contribution to fusion specific tritiated waste management strategy is presented. It is demonstrated that the best strategy is to retain tritium (outgas and recover, or immobilize it) so that residual tritium releases are kept to a minimum. For that, wastes are identified, actual regulations are described and judged inadequate without amendments for fusion problems. Appropriate criteria are defined. Options for treatment and disposal of tritiated wastes are proposed and evaluated. A tritium recovery solution is described

  12. TFTR tritium inventory accountability system

    Energy Technology Data Exchange (ETDEWEB)

    Saville, C.; Ascione, G.; Elwood, S.; Nagy, A.; Raftopoulos, S.; Rossmassler, R.; Stencel, J.; Voorhees, D.; Tilson, C. [Plasma Physics Lab., Princeton, NJ (United States)

    1995-10-01

    This paper discusses the program, PPPL (Princeton Plasma Physics Laboratory) Material Control and Accountability Plan, that has been implemented to track US Department of Energy`s tritium and all other accountable source material. Specifically, this paper details the methods used to measure tritium in various systems at the Tokamak Fusion Test Reactor; resolve inventory differences; perform inventory by difference inside the Tokamak; process and measure plasma exhaust and other effluent gas streams; process, measure and ship scrap or waste tritium on molecular sieve beds; and detail organizational structure of the Material Control and Accountability group. In addition, this paper describes a Unix-based computerized software system developed at PPPL to account for all tritium movements throughout the facility. 5 refs., 2 figs.

  13. Tritium in fusion reactor components

    International Nuclear Information System (INIS)

    Watson, J.S.; Fisher, P.W.; Talbot, J.B.

    1980-01-01

    When tritium is used in a fusion energy experiment or reactor, several implications affect and usually restrict the design and operation of the system and involve questions of containment, inventory, and radiation damage. Containment is expected to be particularly important both for high-temperature components and for those components that are prone to require frequent maintenance. Inventory is currently of major significance in cases where safety and environmental considerations limit the experiments to very low levels of tritium. Fewer inventory restrictions are expected as fusion experiments are placed in more-remote locations and as the fusion community gains experience with the use of tritium. However, the advent of power-producing experiments with high-duty cycle will again lead to serious difficulties based principally on tritium availability; cyclic operations with significant regeneration times are the principal problems

  14. Reliability and validity of the transport and physical activity questionnaire (TPAQ for assessing physical activity behaviour.

    Directory of Open Access Journals (Sweden)

    Emma J Adams

    Full Text Available No current validated survey instrument allows a comprehensive assessment of both physical activity and travel behaviours for use in interdisciplinary research on walking and cycling. This study reports on the test-retest reliability and validity of physical activity measures in the transport and physical activity questionnaire (TPAQ.The TPAQ assesses time spent in different domains of physical activity and using different modes of transport for five journey purposes. Test-retest reliability of eight physical activity summary variables was assessed using intra-class correlation coefficients (ICC and Kappa scores for continuous and categorical variables respectively. In a separate study, the validity of three survey-reported physical activity summary variables was assessed by computing Spearman correlation coefficients using accelerometer-derived reference measures. The Bland-Altman technique was used to determine the absolute validity of survey-reported time spent in moderate-to-vigorous physical activity (MVPA.In the reliability study, ICC for time spent in different domains of physical activity ranged from fair to substantial for walking for transport (ICC = 0.59, cycling for transport (ICC = 0.61, walking for recreation (ICC = 0.48, cycling for recreation (ICC = 0.35, moderate leisure-time physical activity (ICC = 0.47, vigorous leisure-time physical activity (ICC = 0.63, and total physical activity (ICC = 0.56. The proportion of participants estimated to meet physical activity guidelines showed acceptable reliability (k = 0.60. In the validity study, comparison of survey-reported and accelerometer-derived time spent in physical activity showed strong agreement for vigorous physical activity (r = 0.72, p<0.001, fair but non-significant agreement for moderate physical activity (r = 0.24, p = 0.09 and fair agreement for MVPA (r = 0.27, p = 0.05. Bland-Altman analysis showed a mean

  15. Design and test about de tritium system to filling tritium glove box

    International Nuclear Information System (INIS)

    Lei, Jiarong; Du, Yang; Yang, Yong

    2008-01-01

    In order to deal tritium permeated from inflating tritium system at the scene of inflating tritium, dealing waste tritium gas system was designed according to demand and action of dealing waste tritium gas from inflating tritium, and the data of character and volume about appliance of catalyst reaction and drying agent was calculated. Through the test at the scene of inflating tritium, it is result that dealing waste tritium gas system's efficiency reaches above 85% average in circulatory system, so that it can be used in practice extensively. (author)

  16. Tritium control and accountability instructions

    International Nuclear Information System (INIS)

    Wall, W.R.

    1981-03-01

    This instruction describes the tritium accountability procedures practiced by the Tritium Research Laboratory, Building 968 at Sandia National Laboratories, Livermore. The accountability procedures are based upon the Sandia National Laboratories, Livermore, Nuclear Materials Operations Manual, SAND78-8018. The Nuclear Materials Operations Manual describes accountability techniques which are in compliance with the Department of Energy Manual, Code of Federal Regulations, and Sandia National Laboratories Instructions

  17. Tritium control and accountability instructions

    International Nuclear Information System (INIS)

    Wall, W.R.; Cruz, S.L.

    1985-08-01

    This instruction describes the tritium accountability procedures practiced by the Tritium Research Laboratory, at Sandia National Laboratories, Livermore. The accountability procedures are based upon the Sandia National Laboratories, Livermore, Nuclear Materials Operations Manual, SAND83-8036. The Nuclear Materials Operations Manual describes accountability techniques which are in compliance with the Department of Energy 5630 series Orders, Code of Federal Regulations, and Sandia National Laboratories Instructions

  18. Tritium pellet injector for TFTR

    International Nuclear Information System (INIS)

    Gouge, M.J.; Baylor, L.R.; Cole, M.J.; Combs, S.K.; Dyer, G.R.; Fehling, D.T.; Fisher, P.W.; Foust, C.R.; Langley, R.A.; Milora, S.L.; Qualls, A.L.; Wilgen, J.B.; Schmidt, G.L.; Barnes, G.W.; Persing, R.G.

    1992-01-01

    The tritium pellet injector (TPI) for the Tokamak Fusion Test Reactor (TFTR) will provide a tritium pellet fueling capability with pellet speeds in the 1- to 3-km/s range for the TFTR deuterium-tritium (D-T) phase. The existing TFTR deuterium pellet injector (DPI) has been modified at Oak Ridge National Laboratory (ORNL) to provide a four-shot, tritium-compatible, pipe-gun configuration with three upgraded single-stage pneumatic guns and a two-stage light gas gun driver. The TPI was designed to provide pellets ranging from 3.3 to 4.5 mm in diameter in arbitrarily programmable firing sequences at speeds up to approximately 1.5 km/s for the three single-stage drivers and 2.5 to 3 km/s for the two-stage driver. Injector operation is controlled by a programmable logic controller. The new pipe-gun injector assembly was installed in the modified DPI guard vacuum box, and modifications were made to the internals of the DPI vacuum injection line, including a new pellet diagnostics package. Assembly of these modified parts with existing DPI components was then completed, and the TPI was tested at ORNL with deuterium pellet. Results of the limited testing program at ORNL are described. The TPI is being installed on TFTR to support the D-D run period in 1992. In 1993, the tritium pellet injector will be retrofitted with a D-T fuel manifold and secondary tritium containment systems and integrated into TFTR tritium processing systems to provide full tritium pellet capability

  19. Concept of a tritium extraction facility for a reprocessing plant

    International Nuclear Information System (INIS)

    Tunaboylu, K.; Paulovic, M.; Ulrich, D.

    1991-01-01

    There are several alternatives for reducing the release of tritium to the environment originating from the wastewater of a reprocessing plant. Such alternatives, which are applicable for sites not located by the sea or by large rivers, are limited to either injection of tritiated wastewater into suitable deep geological formations, or final disposal into a deep underground repository after adequate treatment similar to other low and intermediate active waste. Removal of tritium from the wastewater by enrichment represents a further feasible option of the second alternative, which allows reduction of the huge volume of tritiated water to be treated before disposal. A significant volume reduction increases the safety of the subsequent steps such as transport, interim storage and final disposal of tritiated waste, furthermore, decreases the corresponding overall waste management cost. The projected Wackersdorf reprocessing plant has been considered as a reference for assessing the permitted tritium releases and other site characteristics. (orig.)

  20. Separation of Tritium from Wastewater

    International Nuclear Information System (INIS)

    JEPPSON, D.W.

    2000-01-01

    A proprietary tritium loading bed developed by Molecular Separations, Inc (MSI) has been shown to selectively load tritiated water as waters of hydration at near ambient temperatures. Tests conducted with a 126 (micro)C 1 tritium/liter water standard mixture showed reductions to 25 (micro)C 1 /L utilizing two, 2-meter long columns in series. Demonstration tests with Hanford Site wastewater samples indicate an approximate tritium concentration reduction from 0.3 (micro)C 1 /L to 0.07 (micro)C 1 /L for a series of two, 2-meter long stationary column beds Further reduction to less than 0.02 (micro)C 1 /L, the current drinking water maximum contaminant level (MCL), is projected with additional bed media in series. Tritium can be removed from the loaded beds with a modest temperature increase and the beds can be reused Results of initial tests are presented and a moving bed process for treating large quantities of wastewaters is proposed. The moving bed separation process appears promising to treat existing large quantities of wastewater at various US Department of Energy (DOE) sites. The enriched tritium stream can be grouted for waste disposition. The separations system has also been shown to reduce tritium concentrations in nuclear reactor cooling water to levels that allow reuse. Energy requirements to reconstitute the loading beds and waste disposal costs for this process appear modest

  1. Primer on tritium safe handling practices

    Energy Technology Data Exchange (ETDEWEB)

    1994-12-01

    This Primer is designed for use by operations and maintenance personnel to improve their knowledge of tritium safe handling practices. It is applicable to many job classifications and can be used as a reference for classroom work or for self-study. It is presented in general terms for use throughout the DOE Complex. After reading it, one should be able to: describe methods of measuring airborne tritium concentration; list types of protective clothing effective against tritium uptake from surface and airborne contamination; name two methods of reducing the body dose after a tritium uptake; describe the most common method for determining amount of tritium uptake in the body; describe steps to take following an accidental release of airborne tritium; describe the damage to metals that results from absorption of tritium; explain how washing hands or showering in cold water helps reduce tritium uptake; and describe how tritium exchanges with normal hydrogen in water and hydrocarbons.

  2. The valley system of the Jihlava river and Mohelno reservoir with enhanced tritium activities.

    Science.gov (United States)

    Simek, P; Kořínková, T; Svetlik, I; Povinec, P P; Fejgl, M; Malátová, I; Tomaskova, L; Stepan, V

    2017-01-01

    The Dukovany nuclear power plant (NPP Dukovany) releases liquid effluents, including HTO, to the Mohelno reservoir, located in a deep valley. Significantly enhanced tritium activities were observed in the form of non-exchangeable organically bound tritium in the surrounding biota which lacks direct contact with the water body. This indicates a tritium uptake by plants from air moisture and haze, which is, besides the uptake by roots from soil, one of the most important mechanisms of tritium transfer from environment to plants. Results of a pilot study based on four sampling campaigns in 2011-2015 are presented and discussed, with the aim to provide new information on tritium transport in the Mohelno reservoir - Jihlava River - plants ecosystems. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Placental transport of radionuclides. Terminal report, May 1, 1973--July 31, 1975. [Tritiated water, tritium, /sup 14/C, /sup 45/C, and /sup 47/C tracers

    Energy Technology Data Exchange (ETDEWEB)

    Kronfeld, D.S.

    1977-08-01

    Four successful experiments were conducted with tritiated water on pregnant sheep. This came into equilibrium between fetal and maternal circulations within 60 seconds after injection into the ewe or the fetus. The estimates of total water transport rate averaged 85% of the daily water intake. Six successful experiments were conducted with /sup 3/H- and /sup 14/C-glucose on pregnant ewes. The results for glucose space and transport rate in the ewes agree closely with previously published data. The fetal glucose pool size was large, presumably reflecting the relatively large volume of fetal-placental fluids in exchange with fetal blood. Six successful experiments were conducted with /sup 45/Ca and /sup 47/Ca for 5 days or more on pregnant ewes. The smallest compartment size of exchangeable calcium in mother and fetus were about 2 to 6 hours duration, and the net daily gain of calcium by the fetus was just slightly less in the chronic than in the acute experiments, 0.75 and 0.83 g/day respectively.

  4. Applications of tritium in industry and research

    International Nuclear Information System (INIS)

    Murthy, T.S.; Iyengar, T.S.

    1990-01-01

    As a naturally occuring isotope and as an injected tracer tritium has been found to be useful in meteorology, cosmology, geohydrology, biology, agriculture, and medical sciences both in aqueous and organic forms. In selfluminous compounds, paints and plastics the radioisotopic power of tritium (0.26 w/g) is found to be useful. Several biochemically significant tritium labelled compounds have been produced for use in industry and research. Tritium loaded consumer products are extensively used all over the world. In gas chromatographs and for neutron research tritium targets are found to be useful. This review summarises the various aspects of tritium as a tracer. (author). 7 refs., 1 tab., 1 fig

  5. Predictors of technical adoption and behavioural change to transport energy-saving measures in response to climate change

    International Nuclear Information System (INIS)

    Aini, M.S.; Chan, S.C.; Syuhaily, O.

    2013-01-01

    Energy conservation can be achieved through the adoption of technical measures or the changing of one's behaviour. A survey of 201 Malaysian public personnel was conducted to examine the predictors of these two types of transport energy-saving measures in response to climate change. The results indicated that there were significant differences in the relative acceptability of both behavioural measures with respect to gender, level of education, income, knowledge of climate change and attitude. Gender, knowledge of causes of climate change and personal norm were predictors for the acceptability of technical measures, while perceived efficacy and personal norm were the factors that influenced the acceptability of behavioural measures. The results also indicated that distinctions ought to be made between technology adoption and behaviour modifications that require lifestyle changes when assessing pro-environmental intent behaviour. The implications for theory and practice are discussed. - Highlights: • A survey was conducted to examine acceptability of transport energy-saving measures. • Gender, knowledge of causes, efficacy and personal norm are predictors of technical measures. • Personal norm and perceived efficacy influenced acceptability of behavioural change. • Both measures are strongly correlated to psychological factors than to socio-demographic variables

  6. Organically bound tritium analysis in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Baglan, N. [CEA/DAM/DIF, Arpajon (France); Kim, S.B. [AECL, Chalk River Laboratories, Chalk River, ON (Canada); Cossonnet, C. [IRSN/PRP-ENV/STEME/LMRE, Orsay (France); Croudace, I.W.; Warwick, P.E. [GAU-Radioanalytical, University of Southampton, Southampton (United Kingdom); Fournier, M. [IRSN/DG/DMQ, Fontenay-aux-Roses (France); Galeriu, D. [IFIN-HH, Horia-Hulubei, Inst. Phys. and Nucl. Eng., Bucharest (Romania); Momoshima, N. [Kyushu University, Radioisotope Ctr., Fukuoka (Japan); Ansoborlo, E. [CEA/DEN/DRCP/CETAMA, Bagnols-sur-Ceze (France)

    2015-03-15

    Organically bound tritium (OBT) has become of increased interest within the last decade, with a focus on its behaviour and also its analysis, which are important to assess tritium distribution in the environment. In contrast, there are no certified reference materials and no standard analytical method through the international organization related to OBT. In order to resolve this issue, an OBT international working group was created in May 2012. Over 20 labs from around the world participated and submitted their results for the first intercomparison exercise results on potato (Sep 2013). The samples, specially-prepared potatoes, were provided in March 2013 to each participant. Technical information and results from this first exercise are discussed here for all the labs which have realised the five replicates necessary to allow a reliable statistical treatment. The results are encouraging as the increased number of participating labs did not degrade the observed dispersion of the results for a similar activity level. Therefore, the results do not seem to depend on the analytical procedure used. From this work an optimised procedure can start to be developed to deal with OBT analysis and will guide subsequent planned OBT trials by the international group.

  7. Effects of rearing conditions on behavioural and physiological responses of pigs to preslaughter handling and mixing at transport

    NARCIS (Netherlands)

    de Jong, I.C; Prelle, I.T.; Lambooij, E.; Korte, S.M.; Blokhuis, H.J; Koolhaas, J.M.

    The physiological and behavioural responses of slaughter pigs reared in either a barren environment or in an enriched environment (larger pens with straw bedding) to preslaughter handling and mixing at transport were studied. Enriched-reared pigs had higher salivary cortisol concentrations in the

  8. Tritium incorporation in corn and bean after an accute contamination with tritiated water

    International Nuclear Information System (INIS)

    Silva, H.A.; Archundia, C.; Bravo, G.; Nulman, R.; Ortiz Magana, J.R.

    1979-01-01

    Tritium produced by natural or artificial processes is set free in the environment, generally as tritiated water, which the plants use to produce organic compounds such as proteins, fats and carbohidrates. The metabolism of tritium depends on the chemical form in which it is found, transport studies of tritium in different ecosystems, and in particular in food chains, gradually have become more important as a result of the tritium increase in the environment. In Mexico, corn and beans have been studied due to their great importance in the human food chain. The determination of tritium in organic compounds (bound tritium) requires an efficient conversion to tritiated water. For this reason, in this work we have detailed a dry oxidation method, which is a modification of the method of Schoniger, which consists of combustion in oxygen initiated by a simple electrical device using a disposable nichrome resistance, which is also used as a sample carrier. Tritium determination is done by a liquid scintillation counter with quenching correction using an internal standard. Graphs of tritium activity are shown plotted against the time between the application of tritiated water and the time of harvest. The highest activity is found about the 18th day for corn and the 16th day for beans. The calculated values for the half-lives for corn and beans are approximately 56 and 43 days respectively. (author)

  9. Evaluation of Tritium Behavior in the Epoxy Painted Concrete Wall of ITER Hot Cell

    International Nuclear Information System (INIS)

    Nakamura, Hirofumi; Hayashi, Takumi; Kobayashi, Kazuhiro; Nishi, Masataka

    2005-01-01

    Tritium behavior released in the ITER hot cell has been investigated numerically using a combined analytical methods of a tritium transport analysis in the multi-layer wall (concrete and epoxy paint) with the one dimensional diffusion model and a tritium concentration analysis in the hot cell with the complete mixing model by the ventilation. As the results, it is revealed that tritium concentration decay and permeation issues are not serious problem in a viewpoint of safety, since it is expected that tritium concentration in the hot cell decrease rapidly within several days just after removing the tritium release source, and tritium permeation through the epoxy painted concrete wall will be negligible as long as the averaged realistic diffusion coefficient is ensured in the concrete wall. It is also revealed that the epoxy paint on the concrete wall prevents the tritium inventory increase in the concrete wall greatly (two orders of magnitudes), but still, the inventory in the wall is estimated to reach about 0.1 PBq for 20 years operation

  10. Studies on chemical phenomena of high concentration tritium water and organic compounds of tritium from viewpoint of the tritium confinement

    International Nuclear Information System (INIS)

    Yamanishi, Toshihiko; Hayashi, Takumi; Iwai, Yasunori; Isobe, Kanetsugu; Hara, Masanori; Sugiyama, Takahiko; Okuno, Kenji

    2009-01-01

    As a part of the grant-in-aid for scientific research on priority areas entitled 'frontiers of tritium researches toward fusion reactors', coordinated two research programs on chemical phenomena of high concentration tritium water and organic compounds of tritium from view point of the tritium confinement have been conducted by the C01 team. The results are summarized as follows: (1) Chemical effects of the high concentration tritium water on stainless steels as structural materials of fusion reactors were investigated. Basic data on tritium behaviors at the metal-water interface and corrosion of metal in tritium water were obtained. (2) Development of the tritium confinement and extraction system for the circulating cooling water in the fusion reactor was studied. Improvement was obtained in the performance of a chemical exchange column and catalysts as major components of the water processing system. (J.P.N.)

  11. Behavioural Responses in Pigs administered with Ascorbic acid and Transported by Road for Eight Hours during the Harmattan Season

    Directory of Open Access Journals (Sweden)

    Yahaya Adeshina Adenkola

    Full Text Available Experiments were carried out with the aim of investigating the modulatory role of ascorbic acid (AA on responses to 8-h road transportation, covering a distance of 260 km at a speed of 40 - 50 km/h, during the harmattan season. Twentynine adult local pigs aged 9 - 12 months served as subjects. Seventeen pigs administered with AA, prior to the transportation, at the dose of 250 mg/kg orally and individually served as experimental animals, and 12 others administered orally with sterile water were used as control animals. The behavioural activities of pigs which included resting (that is, either lying down or standing idle, defaecating, urinating, sniffing, threats of attack (fight, attempts to escape, mounting on one another, hurdling together and routing the floor were monitored with the aid of a video camera without the pigs knowing that they were being observed. Recordings were done based on the number of pigs found performing each activity within 30 min of direct observation, alternated by 30 min of rest and this continued for a period of 4 h. The tape was later watched, analysed and the number of pigs exhibiting each behavioural activity was recorded. Post-transportation, the behavioural activities of standing (94.1 ± 5.8 %, aggressiveness indicated by the percentage of pigs involved in fighting (23.5 ± 6.00 % and attempts to escape (66.67 ± 14.21 % were higher in experimental pigs (P< 0.05 post-transportation than control pigs with the corresponding values of 25.00 ± 3.00 %; 0.00 % and 35.29 ± 11.95 %, respectively. The results showed that road transportation induced considerable behavioural stress resulting in depression of the central nervous system. AA administration pre-transportation reduced the manifestation of stressful behavioural activities in experimental pigs following road transportation. In conclusion, long-term road transportation of pigs during the harmattan season induces behavioural stress, alleviated by AA

  12. Evaluation of tritium analysis techniques for a continuous tritium monitor

    International Nuclear Information System (INIS)

    Fernandez, S.J.; Girton, R.C.

    1978-04-01

    Present methods for tritium monitoring are evaluated and a program is proposed to modify the existing methods or develop new instrumentation to establish a state-of-the-art monitoring capability for nuclear fuel reprocessing plants. The capabilities, advantages, and disadvantages of the most popular counting and separation techniques are described. The following criteria were used to evaluate present methods: specificity, selectivity, precision, insensitivity to gamma radiation, and economy. A novel approach is explored to continuously separate the tritium from a complex mixture of stack gases. This approach, based on the different permeabilities of the stack gas constituents, is integrated into a complete monitoring system. This monitoring system is designed to perform real time tritium analysis. A schedule is presented for development and demonstration of the completed system

  13. Food chain transport of nanoparticles affects behaviour and fat metabolism in fish.

    Science.gov (United States)

    Cedervall, Tommy; Hansson, Lars-Anders; Lard, Mercy; Frohm, Birgitta; Linse, Sara

    2012-01-01

    Nano-sized (10(-9)-10(-7) m) particles offer many technical and biomedical advances over the bulk material. The use of nanoparticles in cosmetics, detergents, food and other commercial products is rapidly increasing despite little knowledge of their effect on organism metabolism. We show here that commercially manufactured polystyrene nanoparticles, transported through an aquatic food chain from algae, through zooplankton to fish, affect lipid metabolism and behaviour of the top consumer. At least three independent metabolic parameters differed between control and test fish: the weight loss, the triglycerides∶cholesterol ratio in blood serum, and the distribution of cholesterol between muscle and liver. Moreover, we demonstrate that nanoparticles bind to apolipoprotein A-I in fish serum in-vitro, thereby restraining them from properly utilising their fat reserves if absorbed through ingestion. In addition to the metabolic effects, we show that consumption of nanoparticle-containing zooplankton affects the feeding behaviour of the fish. The time it took the fish to consume 95% of the food presented to them was more than doubled for nanoparticle-exposed compared to control fish. Since many nano-sized products will, through the sewage system, end up in freshwater and marine habitats, our study provides a potential bioassay for testing new nano-sized material before manufacturing. In conclusion, our study shows that from knowledge of the molecular composition of the protein corona around nanoparticles it is possible to make a testable molecular hypothesis and bioassay of the potential biological risks of a defined nanoparticle at the organism and ecosystem level.

  14. Recommended radiological controls for tritium operations

    International Nuclear Information System (INIS)

    Mansfield, G.

    1992-01-01

    This informal report presents recommendations for an adequate radiological protection program for tritium operations. Topics include hazards analysis, facility design, personnel protection equipment, training, operational procedures, radiation monitoring, to include surface and airborne tritium contamination, and program management

  15. Tritium in metals: Techniques of preparation

    International Nuclear Information System (INIS)

    Laesser, R.; Klatt, K.H.; Mecking, P.; Wenzl, H.

    1982-08-01

    In order to study the behavior of tritium in metals, an all metal apparatus has been built for the safe handling of 100 mg of tritium. Samples of palladium, vanadium, niobium, and tantalum were loaded with tritium, deuterium or hydrogen. Some details of the phase diagrams could be established by DTA and by measurement of the lattice parameters. The diffusion of tritium in V, Nb, and Ta was studied with the Gorsky-effect. (TWO)

  16. Tritium decontamination of machine components and walls

    International Nuclear Information System (INIS)

    Hircq, B.; Wong, K.Y.; Jalbert, R.A.; Shmayda, W.T.

    1991-01-01

    Tritium decontamination techniques for machine components and their application at tritium handling facilities are reviewed. These include commonly used methods such as vacuuming, purging, thermal desorption and isotopic exchange as well as less common methods such as chemical/electrochemical etching, plasma discharge cleaning, and destructive methods. Problems associated with tritium contamination of walls and use of protective coatings are reviewed. Tritium decontamination considerations at fusion facilities are discussed

  17. Design of the Target Fabrication Tritium Laboratory

    International Nuclear Information System (INIS)

    Sherohman, J.W.; Roberts, D.H.; Levine, B.H.

    1982-01-01

    The design of the Target Fabrication Tritium Laboratory for deuterium-tritium fuel processing for laser fusion targets has been accomplished with the intent of providing redundant safeguard systems. The design of the tritium laboratory is based on a combination of tritium handling techniques that are currently used by experienced laboratories. A description of the laboratory in terms of its interrelated processing systems is presented to provide an understanding of the design features for safe operation

  18. Surface air pollution with oxidized tritium during its momentary fallout with atmospheric precipitations

    International Nuclear Information System (INIS)

    Vorontsov, A.I.; Koloskov, I.A.; Nekozyrev, A.F.; Pastukhov, B.V.

    1976-01-01

    Regularities of the behaviour of tritium fallen out to the surface of the Earth as a result of peaceful thermonuclear explosions and the operation of atomic power plants were studied. With this purpose in view determined was the velocity of the decnatural ontamination of the soil-vegetation cover contaminated with tritium oxide due to evapouration, in connection with the density of the area contamination and the tritium content in the near-ground layer of iar. The study was carried out by modelling a single fallout of tritium oxide with atmospheric precipita--tions in different seasons of the year. Fallouts were simulated by applying tritiated water to experimental plots located in the forest-and-steppe zone. It has been found out that the intensive evapouration of tritium occurs during the first day after the contamination. The content of oxidized tritium in the near-ground layer of air is determined by the density of the contamination of the upper layer of soil, depends on the size of the contaminated territory and meteorological conditions. A model of the moving out of oxidized tritium into the atmosphere is obtained after it has fallen out to the ground; this model quantitatively describes the process of its evapouration into the near-ground layer of air

  19. Linear accelerator for tritium production

    International Nuclear Information System (INIS)

    Garnett, R.W.; Billen, J.H.; Chan, K.C.D.

    1995-01-01

    For many years now, Los Alamos National Laboratory has been working to develop a conceptual design of a facility for accelerator production of tritium (API). The APT accelerator will produce high energy protons which will bombard a heavy metal target, resulting in the production of large numbers of spallation neutrons. These neutrons will be captured by a low-Z target to produce tritium. This paper describes the latest design of a room-temperature, 1.0 GeV, 100 mA, cw proton accelerator for tritium production. The potential advantages of using superconducting cavities in the high-energy section of the linac are also discussed and a comparison is made with the baseline room-temperature accelerator

  20. Implanted-tritium permeation experiment

    International Nuclear Information System (INIS)

    Hsu, P.Y.; Longhurst, G.R.; Miller, L.G.; Watts, K.D.; Kershner, C.J.; Rogers, M.L.

    1981-01-01

    Recent theoretical investigations have pointed to considerable uncertainty in estimating the amount of tritium which will permeate the first wall of a fusion reactor and enter the primary coolant system due in part to the implantation of energetic ions. An experiment is being planned to study this problem in a small test reactor where the 3 He(n,p) 3 T reaction is used to generate protons and tritons for implantation in and permeation of a simulated first wall. By comparing the amount of tritium moving through the wall in the presence of implantation with that in its absence while maintaining the time background partial pressure and temperature, the efflct of implantation on tritium permeation will be determined. The experiment offers an interesting and important complement to similar experiments based on plasmas or ion beams

  1. Tritium calorimeter setup and operation

    CERN Document Server

    Rodgers, D E

    2002-01-01

    The LBNL tritium calorimeter is a stable instrument capable of measuring tritium with a sensitivity of 25 Ci. Measurement times range from 8-hr to 7-days depending on the thermal conductivity and mass of the material being measured. The instrument allows accurate tritium measurements without requiring that the sample be opened and subsampled, thus reducing personnel exposure and radioactive waste generation. The sensitivity limit is primarily due to response shifts caused by temperature fluctuation in the water bath. The fluctuations are most likely a combination of insufficient insulation from ambient air and precision limitations in the temperature controller. The sensitivity could probably be reduced to below 5 Ci if the following improvements were made: (1) Extend the external insulation to cover the entire bath and increase the top insulation. (2) Improve the seal between the air space above the bath and the outside air to reduce evaporation. This will limit the response drift as the water level drops. (...

  2. Tritium oxidation and exchange: preliminary studies

    International Nuclear Information System (INIS)

    Phillips, J.E.; Easterly, C.E.

    1978-05-01

    The radiological hazard resulting from an exposure to either tritium oxide or tritium gas is discussed and the factors contributing to the hazard are presented. From the discussion it appears that an exposure to tritium oxide vapor is 10 4 to 10 5 times more hazardous than exposure to tritium gas. Present and future sources of tritium are briefly considered and indicate that most of the tritium has been and is being released as tritium oxide. The likelihood of gaseous releases, however, is expected to increase in the future, calling to task the present general release assumption that 100% of all tritium released is as oxide. Accurate evaluation of the hazards from a gaseous release will require a knowledge of the conversion rate of tritium gas to tritium oxide. An experiment for determining the conversion rate of tritium gas to tritium oxide is presented along with some preliminary data. The conversion rates obtained for low initial concentrations (10 -4 to 10 -1 mCi/ml) indicate the conversion may proceed more rapidly than would be expected from an extrapolation of previous data taken at higher concentrations

  3. 10 CFR 30.55 - Tritium reports.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Tritium reports. 30.55 Section 30.55 Energy NUCLEAR..., Inspections, Tests, and Reports § 30.55 Tritium reports. (a)-(b) [Reserved] (c) Except as specified in paragraph (d) of this section, each licensee who is authorized to possess tritium shall report promptly to...

  4. Toxicity and dosimetry of tritium

    International Nuclear Information System (INIS)

    Myers, D.K.; Johnson, J.R.

    1991-01-01

    Tritium doses to the general public are very low (currently about 0.2 μSv per year). Radiation doses from tritium to members of the public living in the vicinity of a CANDU power station are higher but rarely exceed 20 μSv per year or 1% of normal exposures to radiation from all natural sources, but doses to some radiation workers can approach ten mSv per year. The relative biological effectiveness (RBE) of tritium beta rays varies appreciably depending upon the biological endpoint. Observed RBE values at low doses and low dose-rates are usually about 2 to 3 when tritium beta rays are compared to 60 Co gamma rays but are closer to 1 than to 2 when compared to 200 kVp X-rays. This conclusion is supported by microdosimetric considerations of the quality of tritium beta rays, 60 Co gamma rays and X-rays. Since X-rays have traditionally been accepted as reference radiation by the International Commission on Radiological Protection, it seems reasonable that the quality factor (Q) assigned to tritium beta rays should be close to one. Recommended procedures in Canada for estimation of effective dose equivalents from exposures to HTO and HT assume that Q = 1 and that body water represents 67% of the mass of soft tissue; they take into account conversions of HTO to appear to be reasonable for radiation protection purposes when the source of exposure is HTO or HT, but will not be adequate for exposures to other tritiated compounds. (modified author abstract) (137 refs., 11 figs., 12 tabs.)

  5. Pollution abatement from road transport: cross-sectoral implications, climate co-benefits and behavioural change

    International Nuclear Information System (INIS)

    Oxley, T.; Elshkaki, A.; Kwiatkowski, L.; Castillo, A.; Scarbrough, T.; ApSimon, H.

    2012-01-01

    With the abatement potential of end-of-pipe technologies for road transport becoming increasingly marginal, and with greater emissions reductions still needed in order to reduce pollution, alternative strategies involving behavioural change and choices between fossil fuelled or low carbon vehicles becomes more important. The environmental requirements include local air quality objectives, meeting national emissions ceilings to limit transboundary effects, and to aspire to significant reductions in greenhouse gas emissions. In this paper we use the BRUTAL sub-model of the UK integrated Assessment Model (UKIAM) to investigate a selection of alternative strategies including downsizing of cars, switching from petrol to diesel, and the introduction of electric, bio-fuelled or hydrogen vehicles into the fleet, relative to a business-as-usual projection for 2020. Projected impacts upon air quality limit values, national emissions ceilings and CO 2 emissions are assessed in relation to local, national and international objectives. We discuss related life-cycle impacts, implications for infrastructure, and potential impacts upon emissions from other sectors in order to highlight the full potential implications of the different strategies within the context of changes resulting from other policy developments at different scales.

  6. Description of the new version 4.0 of the tritium model UFOTRI including user guide

    International Nuclear Information System (INIS)

    Raskob, W.

    1993-08-01

    In view of the future operation of fusion reactors the release of tritium may play a dominant role during normal operation as well as after accidents. Because of its physical and chemical properties which differ significantly from those of other radionuclides, the model UFOTRI for assessing the radiological consequences of accidental tritium releases has been developed. It describes the behaviour of tritium in the biosphere and calculates the radiological impact on individuals and the population due to the direct exposure and by the ingestion pathways. Processes such as the conversion of tritium gas into tritiated water (HTO) in the soil, re-emission after deposition and the conversion of HTO into organically bound tritium, are considered. The use of UFOTRI in its probabilistic mode shows the spectrum of the radiological impact together with the associated probability of occurrence. A first model version was established in 1991. As the ongoing work on investigating the main processes of the tritium behaviour in the environment shows up new results, the model has been improved in several points. The report describes the changes incorporated into the model since 1991. Additionally provides the up-dated user guide for handling the revised UFOTRI version which will be distributed to interested organizations. (orig.) [de

  7. Tritium turnover in succulent plants

    International Nuclear Information System (INIS)

    Krishnamoorthy, T.M.; Gogate, S.S.; Soman, S.D.

    1977-01-01

    Measurements of turnover rates for tissue free water tritium (TFWT) and tissue bound tritium (TBT) were carried out in three succulent plants, Opuntia sp., E. Trigona and E. Mili using tritiated water as tracer. The estimated half-times were 52, 57.5 and 80 days for TFWT and 212, 318 and 132 days for TBT in the stems of the above plants respectively. Opuntia sp. showed significant incorporation of TBT, 10% of TFWT on weight basis, while the other two plants showed lesser incorporation, 2-3% of TFWT. However, the leaves of E. Mili indicated the same level of fixation of TBT as the stem of Opuntia sp. (author)

  8. Investigating Unsaturated Zone Travel Times with Tritium and Stable Isotopes

    Science.gov (United States)

    Visser, A.; Thaw, M.; Van der Velde, Y.

    2017-12-01

    Travel times in the unsaturated zone are notoriously difficult to assess. Travel time tracers relying on the conservative transport of dissolved (noble) gases (tritium-helium, CFCs or SF6) are not applicable. Large water volume requirements of other cosmogenic radioactive isotopes (sulfur-35, sodium-22) preclude application in the unsaturated zone. Prior investigations have relied on models, introduced tracers, profiles of stable isotopes or tritium, or a combination of these techniques. Significant unsaturated zone travel times (UZTT) complicate the interpretation of stream water travel time tracers by ranked StorAge Selection (rSAS) functions. Close examination of rSAS functions in a sloping soil lysimeter[1] show the effect of the UZTT on the shape of the rSAS cumulative distribution function. We studied the UZTT at the Southern Sierra Critical Zone Observatory (SS-CZO) using profiles of tritium and stable isotopes (18O and 2H) in the unsaturated zone, supported by soil water content data. Tritium analyses require 100-500 mL of soil water and therefore large soil samples (1-5L), and elaborate laboratory procedures (oven drying, degassing and noble gas mass spectrometry). The high seasonal and interannual variability in precipitation of the Mediterranean climate, variable snow pack and high annual ET/P ratios lead to a dynamic hydrology in the deep unsaturated soils and regolith and highly variable travel time distributions. Variability of the tritium concentration in precipitation further complicates direct age estimates. Observed tritium profiles (>3 m deep) are interpreted in terms of advective and dispersive vertical transport of the input variability and radioactive decay of tritium. Significant unsaturated zone travel times corroborate previously observed low activities of short-lived cosmogenic radioactive nuclides in stream water. Under these conditions, incorporating the UZTT is critical to adequately reconstruct stream water travel time distributions. 1

  9. Tritium monitoring in the GCFR sweep gas fuel irradiation capsule BG-10

    International Nuclear Information System (INIS)

    Gat, U.; Pruitt, M.E.; Longest, A.W.; Epstein, B.D.

    1980-01-01

    The release of tritium and its transport pathways were studied in a vented, pressure-equalized fuel rod which simulated a fuel rod in a Gas-Cooled Fast Reactor (GCFR). The purpose was to determine the fraction of total tritium production transported via the various pathways and to determine its chemical form (tritiated hydrogen or water). It was concluded that the fuel rod and its effluent venting lines retained low concentrations of HT (or T 2 ) and any HTO (or T 2 O) present. However, the addition of 1% hydrogen to the helium carrier gas quantitatively eluted the tritium from the charcoal trap integral to the fuel rod and from the effluent lines. The chemical composition of the tritium arriving at the monitoring system could be determined by means of converters which convert HT to HTO and vice versa. Ht was the dominant species in the samples measured

  10. Normalized Tritium Quantification Approach (NoTQA) a Method for Quantifying Tritium Contaminated Trash and Debris at LLNL

    International Nuclear Information System (INIS)

    Dominick, J.L.; Rasmussen, C.L.

    2008-01-01

    Several facilities and many projects at LLNL work exclusively with tritium. These operations have the potential to generate large quantities of Low-Level Radioactive Waste (LLW) with the same or similar radiological characteristics. A standardized documented approach to characterizing these waste materials for disposal as radioactive waste will enhance the ability of the Laboratory to manage them in an efficient and timely manner while ensuring compliance with all applicable regulatory requirements. This standardized characterization approach couples documented process knowledge with analytical verification and is very conservative, overestimating the radioactivity concentration of the waste. The characterization approach documented here is the Normalized Tritium Quantification Approach (NoTQA). This document will serve as a Technical Basis Document which can be referenced in radioactive waste characterization documentation packages such as the Information Gathering Document. In general, radiological characterization of waste consists of both developing an isotopic breakdown (distribution) of radionuclides contaminating the waste and using an appropriate method to quantify the radionuclides in the waste. Characterization approaches require varying degrees of rigor depending upon the radionuclides contaminating the waste and the concentration of the radionuclide contaminants as related to regulatory thresholds. Generally, as activity levels in the waste approach a regulatory or disposal facility threshold the degree of required precision and accuracy, and therefore the level of rigor, increases. In the case of tritium, thresholds of concern for control, contamination, transportation, and waste acceptance are relatively high. Due to the benign nature of tritium and the resulting higher regulatory thresholds, this less rigorous yet conservative characterization approach is appropriate. The scope of this document is to define an appropriate and acceptable

  11. Refugees and transportation in Vermont : travel behaviour and critical questions based on gender, age and transportation hierarchies.

    Science.gov (United States)

    2013-03-01

    This : study : examines : the : travel : behaviour : and : attitudes : of : recently : resettled : refugees : in : Chittenden : County, : Vermont, : with : particular : attention : to : distinctions : based : on : gender : and : age. : It : is : base...

  12. Tritium processing in JT-60U

    International Nuclear Information System (INIS)

    Miya, Naoyuki; Masaki, Kei

    1997-01-01

    Tritium retention analysis and tritium concentration measurement have been made during the large Tokamak JT-60U deuterium operations. This work has been carried out to evaluate the tritium retention for graphite tiles inside the vacuum vessel and tritium release characteristics in the tritium cleanup operations. JT-60U has carried out D-D experiments since July 1991. In the deuterium operations during the first two years, about 1.7 x 10 19 D-D fusion neutrons were produced by D (d, p) T reactions in plasma, which are expected to produce ∼31 GBq of tritium. The tritium produced is evacuated by a pumping system. A part of tritium is, however, trapped in the graphite tiles. Several sample tiles were removed from the vessel and the retained tritium Distribution in the tiles was measured using a liquid scintillator. The results of poloidal distribution showed that the tritium concentration in the divertor tiles was higher than that in the first wall tiles and it peaked in the tiles between two strike points of divertor magnetic lines. Tritium concentration in the exhaust gas from the vessel have also been measured with an ion chamber during the tritium cleanup operations with hydrogen divertor discharges and He-GDC. Total of recovered tritium during the cleanup operations was ∼ 7% of that generated. The results of these measurements showed that the tritium of 16-23 GBq still remained in the graphite tiles, which corresponded to about 50-70% of the tritium generated in plasma. The vessel is ventilated during the in-vessel maintenance works, then the atmosphere is always kept lower than the legal concentration guide level of 0.7 Bq/cm 3 for radiation work permit requirements. (author)

  13. Tritium compatibility of alumina and Fosterite

    Energy Technology Data Exchange (ETDEWEB)

    Coffin, D.O.

    1979-09-01

    Many pressure measurements are required to control processing of the fuel gases associated with fusion power reactors. Since most pressure transducers respond to changes in pressure sensitive electrical parameters, insulators will be required to withstand chronic exposures to concentrated tritium. For this investigation samples of alumina and Fosterite were exposed to concentrated tritium gas for 11 weeks. Gas phase impurities were then analyzed for clues that would indicate decomposition of the exposed materials. The only gaseous impurity resulting from these tritium exposures was tritio-methane, which is always produced when tritium is stored in stainless steel containers. There was no evidence that either alumina or Fosterite decomposed in the presence of tritium.

  14. Synthesis of plant hormones labelled by tritium

    International Nuclear Information System (INIS)

    Sidorov, G.V.; Myasoedov, N.F.

    1999-01-01

    Reaction of solid-phase catalytic hydrogenation, isotopic exchange with enriched tritium water, catalytic heterogenous isotopic exchange with gaseous tritium, hydrogenolysis as applied to synthesis of plants labelled by tritium were studied. Auxins, cytokinins, gibberellins, fusicoccins - representatives of the basic hormones of plants - were objects of investigations. In dependence on synthesis method compounds labelled by tritium were prepared with molar radioactivity from 5 up to 155 Ci/mmol. Order of universal approaches to synthesis of plant hormones labelled by tritium was formulated [ru

  15. Management of tritium at nuclear facilities

    International Nuclear Information System (INIS)

    1984-01-01

    This report presents extending summaries of the works of the participants to an IAEA co-ordinated research programme, ''Handling Tritium - bearing effluents and wastes''. The subjects covered include production of tritium in nuclear power plants (mainly heavy water and light water reactors), as well as at reprocessing plants; removal and enrichment of tritium at nuclear facilities; conditioning methods and characteristics of immobilized tritium of low and high concentration; some potential methods of storage and disposal of tritium. In addition to the conclusions of this three-years work, possible activities in the field are recommended

  16. Tritium behavior intentionally released in the room

    International Nuclear Information System (INIS)

    Kobayashi, K.; Hayashi, T.; Iwai, Y.; Yamanishi, T.; Willms, R. S.; Carlson, R. V.

    2008-01-01

    To construct a fusion reactor with high safety and acceptability, it is necessary to establish and to ensure tritium safe handling technology. Tritium should be well-controlled not to be released to the environment excessively and to prevent workers from excess exposure. It is especially important to grasp tritium behavior in the final confinement area, such as the room and/or building. In order to obtain data for actual tritium behavior in a room and/or building, a series of intentional Tritium Release Experiments (TREs) were planned and carried out within a radiologically controlled area (main cell) at Tritium System Test Assembly (TSTA) in Los Alamos National Laboratory (LANL) under US-JAPAN collaboration program. These experiments were carried out three times. In these experiments, influence of a difference in the tritium release point and the amount of hydrogen isotope for the initial tritium behavior in the room were suggested. Tritium was released into the main cell at TSTA/LANL. The released tritium reached a uniform concentration about 30 - 40 minutes in all the experiments. The influence of the release point and the amount of hydrogen isotope were not found to be important in these experiments. The experimental results for the initial tritium behavior in the room were also simulated well by the modified three-dimensional eddy flow analysis code FLOW-3D. (authors)

  17. Weapons engineering tritium facility overview

    Energy Technology Data Exchange (ETDEWEB)

    Najera, Larry [Los Alamos National Laboratory

    2011-01-20

    Materials provide an overview of the Weapons Engineering Tritium Facility (WETF) as introductory material for January 2011 visit to SRS. Purpose of the visit is to discuss Safety Basis, Conduct of Engineering, and Conduct of Operations. WETF general description and general GTS program capabilities are presented in an unclassified format.

  18. Generation of gaseous tritium standards

    International Nuclear Information System (INIS)

    Hohorst, F.A.

    1994-09-01

    The determination of aqueous and non-aqueous tritium in gaseous samples is one type of determination often requested of radioanalytical laboratories. This determination can be made by introducing the sample as a gas into a sampling train containing two silica gel beds separated by.a catalytic oxidizer bed. The first bed traps tritiated water. The sample then passes into and through the oxidizer bed where non-aqueous tritium containing species are oxidized to water and other products of combustion. The second silica gel bed then traps the newly formed tritiated water. Subsequently, silica gel is removed to plastic bottles, deionized water is added, and the mixture is permitted to equilibrate. The tritium content of the equilibrium mixture is then determined by conventional liquid scintillation counting (LSC). For many years, the moisture content of inert, gaseous samples has been determined using monitors which quantitatively electrolyze the moisture present after that moisture has been absorbed by phosphorous pentoxide or other absorbents. The electrochemical reaction is quantitative and definitive, and the energy consumed during electrolysis forms the basis of the continuous display of the moisture present. This report discusses the experimental evaluation of such a monitor as the basis for a technique for conversion of small quantities of SRMs of tritiated water ( 3 HOH) into gaseous tritium standards ( 3 HH)

  19. Elimination of the vesicular acetylcholine transporter in the striatum reveals regulation of behaviour by cholinergic-glutamatergic co-transmission.

    Directory of Open Access Journals (Sweden)

    Monica S Guzman

    2011-11-01

    Full Text Available Cholinergic neurons in the striatum are thought to play major regulatory functions in motor behaviour and reward. These neurons express two vesicular transporters that can load either acetylcholine or glutamate into synaptic vesicles. Consequently cholinergic neurons can release both neurotransmitters, making it difficult to discern their individual contributions for the regulation of striatal functions. Here we have dissected the specific roles of acetylcholine release for striatal-dependent behaviour in mice by selective elimination of the vesicular acetylcholine transporter (VAChT from striatal cholinergic neurons. Analysis of several behavioural parameters indicates that elimination of VAChT had only marginal consequences in striatum-related tasks and did not affect spontaneous locomotion, cocaine-induced hyperactivity, or its reward properties. However, dopaminergic sensitivity of medium spiny neurons (MSN and the behavioural outputs in response to direct dopaminergic agonists were enhanced, likely due to increased expression/function of dopamine receptors in the striatum. These observations indicate that previous functions attributed to striatal cholinergic neurons in spontaneous locomotor activity and in the rewarding responses to cocaine are mediated by glutamate and not by acetylcholine release. Our experiments demonstrate how one population of neurons can use two distinct neurotransmitters to differentially regulate a given circuitry. The data also raise the possibility of using VAChT as a target to boost dopaminergic function and decrease high striatal cholinergic activity, common neurochemical alterations in individuals affected with Parkinson's disease.

  20. Transport behaviour of xenobiotic micropollutants in surface waters - an experimental assessment

    Science.gov (United States)

    Schwientek, Marc; Kuch, Bertram; Rügner, Hermann; Dobramysl, Lorenz; Grathwohl, Peter

    2013-04-01

    Xenobiotics are substances that do not exist in natural systems but are increasingly produced by industrial processes and introduced into the environment. While many of these compounds are eliminated in waste water treatment plants, some are only barely degraded and are discharged into receiving water bodies. Often little is known about their acute or chronic toxicity and even less about their persistence or transport behaviour in aquatic systems. In the present study, the stability and turnover of selected micropollutants along a 7.5 km long segment of the River Ammer in Southwest Germany was investigated (catchment area 134 km²). This stream carries a proportion of treated wastewater which is clearly above the average in German rivers, mainly supplied by a major waste water treatment plant at the upstream end of the studied stream segment. An experimental mass balance approach was chosen where in- and outflow of water and target compounds into and out of the balanced stream segment was measured during base flow conditions. To cover a complete diurnal cycle of wastewater input, pooled samples were collected every 2 h over a sampling period of 24 h. A comparison of bulk mass fluxes showed that carbamazepine, a pharmaceutical, and phosphorous flame retardants, such as TCPP, behave conservative under the given conditions. Some retention was observed for the disinfectant product Triclosan and some polycyclic musk fragrances (e.g., HHCB). TAED, a bleaching activator used in detergents, was completely eliminated along the stream segment. The outcome of the experiment demonstrates the very different persistence of some widely-used micropollutants in aquatic systems. However, the mechanisms involved in their attenuation as well as the fate of the most persistent compounds still remain subject to further research.

  1. Distribution and behavior of tritium in the Coolant-Salt Technology Facility

    International Nuclear Information System (INIS)

    Mays, G.T.; Smith, A.N.; Engel, J.R.

    1977-04-01

    A 1000-MW(e) Molten-Salt Breeder Reactor (MSBR) is expected to produce 2420 Ci/day of tritium. As much as 60 percent of the tritium produced may be transported to the reactor steam system (assuming no retention by the secondary coolant salt), where it would be released to the environment. Such a release rate would be unacceptable. Experiments were conducted in an engineering-scale facility--the Coolant-Salt Technology Facility (CSTF)--to examine the potential of sodium fluoroborate, the proposed coolant salt for an MSBR, for sequestering tritium. The salt was believed to contain chemical species capable of trapping tritium. A series of 5 experiments--3 transient and 2 steady-state experiments--was conducted from July of 1975 through June of 1976 where tritium was added to the CSTF. The CSTF circulated sodium fluoroborate at temperatures and pressures typical of MSBR operating conditions. Results from the experiments indicated that over 90 percent of tritium added at steady-state conditions was trapped by sodium fluoroborate and appeared in the off-gas system in a chemically combined (water-soluble) form and that a total of approximately 98 percent of the tritium added at steady-state conditions was removed through the off-gas system overall

  2. On line tritium measurement; La mesure du tritium en ligne

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2011-07-01

    Berthold Technologies has developed a new beacon able to measure the activity of tritium in the atmosphere. The real-time measurement will allow the operator to be warned of the exceeding of radiation thresholds. The air sample to be measured is mixed with a counting gas (generally argon/methane) and pumped through a proportional counter. The device counts the electric impulses due to the interaction between the beta particles generated by the tritium and the counting gas. The detection threshold is 500 Bq/m{sup 3} for a counting time of 1 hour. The device also allows the operator to get an emission spectrum of the air sample. (A.C.)

  3. Estimation of Biological Effects of Tritium.

    Science.gov (United States)

    Umata, Toshiyuki

    2017-01-01

    Nuclear fusion technology is expected to create new energy in the future. However, nuclear fusion requires a large amount of tritium as a fuel, leading to concern about the exposure of radiation workers to tritium beta radiation. Furthermore, countermeasures for tritium-polluted water produced in decommissioning of the reactor at Fukushima Daiichi Nuclear Power Station may potentially cause health problems in radiation workers. Although, internal exposure to tritium at a low dose/low dose rate can be assumed, biological effect of tritium exposure is not negligible, because tritiated water (HTO) intake to the body via the mouth/inhalation/skin would lead to homogeneous distribution throughout the whole body. Furthermore, organically-bound tritium (OBT) stays in the body as parts of the molecules that comprise living organisms resulting in long-term exposure, and the chemical form of tritium should be considered. To evaluate the biological effect of tritium, the effect should be compared with that of other radiation types. Many studies have examined the relative biological effectiveness (RBE) of tritium. Hence, we report the RBE, which was obtained with radiation carcinogenesis classified as a stochastic effect, and serves as a reference for cancer risk. We also introduce the outline of the tritium experiment and the principle of a recently developed animal experimental system using transgenic mouse to detect the biological influence of radiation exposure at a low dose/low dose rate.

  4. The LLNL portable tritium processing system

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    The end of the Cold War significantly reduced the need for facilities to handle radioactive materials for the US nuclear weapons program. The LLNL Tritium Facility was among those slated for decommissioning. The plans for the facility have since been reversed, and it remains open. Nevertheless, in the early 1990s, the cleanup (the Tritium Inventory Removal Project) was undertaken. However, removing the inventory of tritium within the facility and cleaning up any pockets of high-level residual contamination required that we design a system adequate to the task and meeting today's stringent standards of worker and environmental protection. In collaboration with Sandia National Laboratory and EG ampersand G Mound Applied Technologies, we fabricated a three-module Portable Tritium Processing System (PTPS) that meets current glovebox standards, is operated from a portable console, and is movable from laboratory to laboratory for performing the basic tritium processing operations: pumping and gas transfer, gas analysis, and gas-phase tritium scrubbing. The Tritium Inventory Removal Project is now in its final year, and the portable system continues to be the workhorse. To meet a strong demand for tritium services, the LLNL Tritium Facility will be reconfigured to provide state-of-the-art tritium and radioactive decontamination research and development. The PTPS will play a key role in this new facility

  5. Tritium in Exit Signs | RadTown USA | US EPA

    Science.gov (United States)

    2017-08-07

    Many exit signs contain tritium to light the sign without batteries or electricity. Using tritium in exit signs allows the sign to remain lit if the power goes out. Tritium is most dangerous when it is inhaled or swallowed. Never tamper with a tritium exit sign. If a tritium exit sign is broken, leave the area immediately and notify the building maintenance staff.

  6. The tritium content of precipitation and groundwater at Yola, Nigeria ...

    African Journals Online (AJOL)

    Tritium is a radioactive isotope of hydrogen which occurs in precipitation. In groundwater studies tritium measurements give information on the time of recharge to the system; the tritium content of precipitation being used to estimate the input of tritium to the groundwater system. At Yola, the tritium ontents in precipitation and ...

  7. Preliminary assessment of the tritium inventory and permeation in the plasma facing components of ITER

    International Nuclear Information System (INIS)

    Federici, G.; Holland, D.; Brooks, J.; Causey, R.; Dolan, T.J.; Longhurst, G.

    1995-01-01

    This paper discusses preliminary quantitative predictions for the tritium inventory in- and permeation through the first-wall and divertor PFC's of ITER. The primary plasma facing material under consideration is beryllium, with possible use of tungsten or carbon fiber composites (CFC's) on high-heat-flux surfaces. They use state-of-the-art tritium transport models, in conjunction with design parameters, and loading conditions anticipated for the first-wall, baffle, limiter and divertor. The analysis includes the synergistic effects of erosion on tritium implantation and trapping, which are expected to play a key role, particularly in the divertor regions where the interaction of the plasma with the surfaces will be most severe. The influence of several key parameters that strongly affect tritium build-up and release is assessed. Finally, they discuss the uncertainties in materials properties under ITER operating conditions and the R and D needed to resolve these uncertainties

  8. Tritium isotope separation from light and heavy water by bipolar electrolysis

    International Nuclear Information System (INIS)

    Petek, M.; Ramey, D.W.; Taylor, R.D.; Kobisk, E.H.

    1980-01-01

    A process for separating tritium from light and heavy water is described. Hydrogen is transferred at and through bipolar electrodes at rates H > D > T. In a cell containing several bipolar electrodes placed in series between two terminal electrodes, a flow of hydrogen is established from the terminal anode compartment toward the terminal cathode. An electrolyte feed containing tritium is continuously added to the system and is subsequently transported countercurrent to the hydrogen mass transfer. A cascaded system is established, in which effluent streams enriched and depleted in tritium can be withdrawn. The voltage drop is smaller at any bipolar electrode as compared to the voltage for normal electrolysis. Cell design is compact because isotope separation occurs at bipolar electrodes without evolution of gas. Isotope separation was demonstrated in laboratory cells where a steady-state tritium concentration gradient was attained. This gradient was in agreement with concentrations calculated from a derived mathematical model

  9. Tritium system for a tokamak reactor with a self-pumped limiter

    International Nuclear Information System (INIS)

    Hassanein, A.M.; Sze, D.K.

    1986-01-01

    The self-pumping concept was proposed as a means of simplifying the impurity control system in a fusion reactor. The idea is to remove helium in-situ by trapping in freshly deposited metal surface layers of a limiter or divertor. Trapping material is added to the plasma scrape-off or edge region where it is transported to the wall. Some of the key issues for this concept are the tritium inventory in the trapping material and the permeation of protium and recycling of tritium. These quantities are shown to be acceptable for the reference design. The tritium issues for a helium-cooled solid breeder reactor design with vanadium alloy as a structural material are also examined. Models are presented for tritium permeation and inventory calculation for structure materials with the effect of a thin layer of coating material

  10. Distribution of tritium in estuarine waters: the role of organic matter

    International Nuclear Information System (INIS)

    Turner, Andrew; Millward, Geoffrey E.; Stemp, Martin

    2009-01-01

    Tritium is an important environmental radionuclide whose reactivity with ligands and solids in aquatic systems is assumed to be limited. We studied the fractionation and sorption of tritium (added as tritiated water) in river water and seawater, and found that its distribution appears to be influenced by its affinity for organic matter. Tritium rapidly equilibrates with dissolved organic ligands that are retained by a reverse-phase C18 column, and with suspended sediment particles. Significantly, a measurable fraction of sorbed tritium associates with proteinaceous material that is potentially available to sediment-feeding organisms. These characteristics have not been reported previously and cannot be accounted for solely by isotopic exchange with hydrogen. Nevertheless, they are in qualitative agreement with available measurements of tritium in estuarine and coastal waters where its principal discharge is as tritiated water. Further research into the estuarine biogeochemical behaviour of tritium is required and radiological distribution coefficients and concentration factors that are assumed for this radionuclide may require reconsideration.

  11. Tritium retention in candidate next-step protection materials: engineering key issues and research requirements

    International Nuclear Information System (INIS)

    Federici, G.; Andrew, P.L.; Wu, C.H.

    1995-01-01

    Although a considerable volume of valuable data on the behaviour of tritium in beryllium and carbon-based armours exposed to hydrogenic fusion plasmas has been compiled over the past years both from operation of present-day tokamaks and from laboratory simulations, knowledge is far from complete and tritium inventory predictions for these materials remain highly uncertain. In this paper we elucidate the main mechanisms responsible for tritium trapping and release in next-step D-T tokamaks, as well as the applicability of some of the presently known data bases for design purposes. Owing to their strong anticipated implications on tritium uptake and release, attention is focused mainly on the interaction of tritium with neutron damage induced defects, on tritium codeposition with eroded carbon and on the effects of oxide and surface contaminants. Some preliminary quantitative estimates are presented based on most recent experimental findings and latest modelling developments as well. The influence of important working conditions such as target temperature, loading particle fluxes, erosion and redeposition rates, as well as material characteristics such as the type of morphology of the protection material (i.e. amorphous plasma-sprayed beryllium vs. solid forms), and design dependent parameters are discussed in this paper. Remaining issues which require additional effort are identified. (orig.)

  12. Radiological training for tritium facilities

    International Nuclear Information System (INIS)

    1996-12-01

    This program management guide describes a recommended implementation standard for core training as outlined in the DOE Radiological Control Manual (RCM). The standard is to assist those individuals, both within DOE and Managing and Operating contractors, identified as having responsibility for implementing the core training recommended by the RCM. This training may also be given to radiological workers using tritium to assist in meeting their job specific training requirements of 10 CFR 835

  13. Radiological training for tritium facilities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    This program management guide describes a recommended implementation standard for core training as outlined in the DOE Radiological Control Manual (RCM). The standard is to assist those individuals, both within DOE and Managing and Operating contractors, identified as having responsibility for implementing the core training recommended by the RCM. This training may also be given to radiological workers using tritium to assist in meeting their job specific training requirements of 10 CFR 835.

  14. HiPER Tritium factory elements

    Science.gov (United States)

    Guillaume, Didier

    2011-06-01

    HiPER will include a Tritium target factory. This presentation is an overview. We start from process ideas to go to first sketch passing through safety principles. We will follow the Tritium management process. We need first a gas factory producing the right gas mixture from hydrogen, Deuterium and Tritium storage. Then we could pass through the target factory. It is based on our LMJ single shot experiment and some new development like the injector. Then comes pellet burst and vapour recovery. The Tritium factory has to include the waste recovery, recycling process with gas purification before storage. At least, a nuclear plant is not a classical building. Tritium is also very special... All the design ideas have to be adapted. Many facilities are necessary, some with redundancy. We all have to well known these constraints. Tritium budget will be a major contributor for a material point of view as for a financial one.

  15. Tritium Removal from Carbon Plasma Facing Components

    International Nuclear Information System (INIS)

    Skinner, C.H.; Coad, J.P.; Federici, G.

    2003-01-01

    Tritium removal is a major unsolved development task for next-step devices with carbon plasma-facing components. The 2-3 order of magnitude increase in duty cycle and associated tritium accumulation rate in a next-step tokamak will place unprecedented demands on tritium removal technology. The associated technical risk can be mitigated only if suitable removal techniques are demonstrated on tokamaks before the construction of a next-step device. This article reviews the history of codeposition, the tritium experience of TFTR (Tokamak Fusion Test Reactor) and JET (Joint European Torus) and the tritium removal rate required to support ITER's planned operational schedule. The merits and shortcomings of various tritium removal techniques are discussed with particular emphasis on oxidation and laser surface heating

  16. Purification of tritium-free water

    International Nuclear Information System (INIS)

    Hussain, S.D.

    1982-10-01

    Ground water which has been out of contact with the atmosphere for a long time as compared to the half life of tritium (12.43 years) does not contain any measureable amount of tritium. Such water is called tritium-free water. It may contain dissolved and suspended impurities and has to be purified before it can be used for the preparation of blanks and standards required in the routine measurement of low level tritium in water samples. The purification of tritium-free water by distillation in a closed system has been described. The quality of processed tritium-free water was precisely checked at International Atomic Energy Agency (IAEA) Vienna and found satisfactory. (authors)

  17. Tritium management in fusion reactors

    International Nuclear Information System (INIS)

    Galloway, T.R.

    1978-05-01

    This is a review paper covering the key environmental and safety issues and how they have been handled in the various magnetic and inertial confinement concepts and reference designs. The issues treated include: tritium accident analyses, tritium process control, occupational safety, HTO formation rate from the gas-phase, disposal of tritium contaminated wastes, and environmental impact--each covering the Joint European Tokamak (J.E.T. experiment), Tokamak Fusion Test Reactor (TFTR), Russian T-20, The Next Step (TNS) designs by Westinghouse/ORNL and General Atomic/ANL, the ANL and ORNL EPR's, the G.A. Doublet Demonstration Reactor, the Italian Fintor-D and the ORNL Demo Studies. There are also the following full scale plant reference designs: UWMAK-III, LASL's Theta Pinch Reactor Design (RTPR), Mirror Fusion Reactor (MFR), Tandem Mirror Reactor (TMR), and the Mirror Hybrid Reactor (MHR). There are four laser device breakeven experiments, SHIVA-NOVA, LLL reference designs, ORNL Laser Fusion power plant, the German ''Saturn,'' and LLL's Laser Fusion EPR I and II

  18. Tritium production in fusion reactors

    International Nuclear Information System (INIS)

    Roth, E.

    1981-08-01

    The present analyses on the possibilities of extracting tritium from the liquid and solid fusion reactor blankets show up many problems. A consistent ensemble of materials and devices for extracting the heat and the tritium has not yet been integrated in a fusion reactor blanket project. The dimensioning of the many pipes required for shifting the tritium can only be done very approximately and the volume taken up by the blanket is difficult to evaluate, etc. The utilization of present data leads to over-dimensioning the installations by prudence and perhaps rejecting the best solutions. In order to measure the parameters of the most promising materials, work must be carried out on well defined samples and not only determine the base physical-chemical coefficients, such as thermal conductivity, scattering coefficients, Sievert parameters, but also the kinetic parameters conventional in chemical engineering, such as the hourly space rates of degassing. It is also necessary to perform long duration experiments under radiation and at operating temperatures, or above, in order to study the ageing of the bodies employed [fr

  19. Regulating tritium in drinking water

    International Nuclear Information System (INIS)

    Fluke, R.

    1994-01-01

    This article incorporates an article by E. Koehl from an internal Ontario Hydro publication, and a letter from the Joint Committee of Health and Safety of the Royal Society of Canada and the Canadian Academy of Engineering, submitted to the Ontario Minister of the Environment and Energy. The Advisory Committee on Environmental Standards had recommended that the limit for tritium in Ontario drinking water be reduced from 40,000 to 100 Bq/L, with a further reduction to 20 in five years. Some facts and figures are adduced to show that the effect of tritium in drinking water in Ontario is negligible compared to the effect of background radiation. The risk from tritium to the people of Ontario is undetectably small, and the attempt to estimate this risk by linear extrapolation is extremely dubious. Regulation entails social and economic costs, and the government ought to ensure that the benefits exceed the costs. The costs translate into nothing less than wasted opportunity to save lives in other ways. 3 refs

  20. Predicted fate of tritium residuum from groundwater tracer experiments in the Amargosa Desert, southern Nevada

    International Nuclear Information System (INIS)

    Brikowski, T.

    1993-07-01

    Analytic solutions are used in this study to evaluate potential groundwater transport of tritium used in goundwater tracer tests southwest of the Nevada Test Site. Possible transport from this site is of interest because initial radionuclide concentrations were high and the site is close to goundwater discharge points (12 km). Anecdotal evidence indicates that 90 percent of these tracers were removed by pumping at the completion of the tests; this study examines the probable transport of the tracers with and without the removal. Classical dispersive transport analytic solutions are used, treating the tracer test as a point slug injection. Input parameters for the solutions were measured at the site, and consideration of parameter uncertainty is incorporated in the results. With removal of the tracer, the maximum expected region with above-Safe Drinking Water Act (40 CFR 121) concentrations of tritium extends 5 km from the injection point, and does not reach any sites of public access. Detectable tritium from the tests is likely to have reached the Ash Meadows fault zone, but flow along the fault probably diluted the tracer to below detection limits before arrival at springs along the fault. Arrival at the springs would have occurred 20 to 25 years after the tests. Without removal of the tracer, the solutions indicate that tritium concentrations just above Safe Drinking Water Act standards would have reached the Ash Meadows fault zone. In this case, detectable tritium might have been found in Devil's Hole or Longstreet Spring, the nearest points of possible public exposure

  1. Contribution to the study of cementitious and clayey materials behaviour in the context of deep geological disposal: transport aspect, durability and thermo-hydro-mechanical behaviour

    International Nuclear Information System (INIS)

    Galle, C.

    2011-07-01

    Deep geological formation disposal is the reference solution in France for the management of medium and high activities radioactive waste. In this context, to demonstrate the feasibility of such a disposal, it is necessary to evaluate the long-term performances and the behaviour of the materials engaged in the elaboration of engineered barrier systems (EBS) and waste package elements. The studies mentioned and synthesized in this HDR thesis focused mainly on the convective transport of gas (under pressure gradient) in cementitious matrices, by coupling microstructure aspect (porosity/pores sizes distribution) and hydric environment (water saturation). Works on physico-chemical durability allowed the description of the chemical degradation of cement-based materials in extreme conditions using ammonium nitrate, to increase the materials damaging processes in order to identify functional margins. In relationship with the interim storage management phase, studies related to the behaviour and characterization of concrete submitted to high temperatures (up to 400 C) were also described. Finally, results concerning the gas (H 2 ) overpressure resistance of engineered barriers made of compacted clays were summarized. (author)

  2. Tritium handling systems for TFTR and PITR

    International Nuclear Information System (INIS)

    Lind, K.E.; Yemin, L.; Rossmassler, R.; Phillips, H.O.; Youssef, N.S.; Levine, J.D.; Howe, H.J.; Pierce, C.W.

    1978-01-01

    Operation of the Tokamak Fusion Test Reactor (TFTR) and the proposed Princeton Ignition Test Reactor (PITR) will involve the generation and burning of a deuterium-tritium plasma. Systems associated with both the TFTR and PITR will be designed to minimize the potential release of tritium and other radioisotopes under both routine operational and accidental conditions. Systems have been proposed for the control and processing of large tritium inventories

  3. Tritium-Powered Radiation Sensor Network

    Science.gov (United States)

    2015-09-01

    sources Tritium-filled, phosphor-lined vials are commercially available for night-vision gear applications.16 The tritium capsules purchased...support and are filled with silicon (Si) rubber adhesive producing sealed modules that meet DOT shipping regulations. The BA5590-style military...Ag) phosphor in the tritium capsules was not always a spectral match to all PV cells. We discovered that space-grade heterojunction PV cells (multi

  4. Tritium radioluminescent devices, Health and Safety Manual

    Energy Technology Data Exchange (ETDEWEB)

    Traub, R.J.; Jensen, G.A.

    1995-06-01

    This document consolidates available information on the properties of tritium, including its environmental chemistry, its health physics, and safe practices in using tritium-activated RL lighting. It also summarizes relevant government regulations on RL lighting. Chapters are divided into a single-column part, which provides an overview of the topic for readers simply requiring guidance on the safety of tritium RL lighting, and a dual-column part for readers requiring more technical and detailed information.

  5. Ontario approves limited sales of tritium

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    The Ontario government announced at the end of August 1989 that it had authorized the limited sale of tritium to help establish a self-powered lighting industry, and for certain other specified purposes including fusion research. To ensure that the tritium will be used only for peaceful purposes, sales will be restricted and subject to strict controls. All sales of tritium will be made public

  6. The movement of tritium in ecological systems

    International Nuclear Information System (INIS)

    Polevoy, Y; Laichter, Y.

    1988-11-01

    This literature survey summarizes the interaction of tritium gas and tritiated water with various components of the ecological system. The intake of tritium gas and tritiated water in plants and soil is described as well as the location of the highest measurable concentration. This information may serve as a basis for risk assessment from tritium to man through the food chain and enables effective tracing of its concentration in the environment. (author)

  7. Degradation of elastomers by tritium beta radiation

    International Nuclear Information System (INIS)

    Zapp, P.E.; Tuer, G.L. Jr.

    1984-01-01

    Based on its tritium radiation resistance, ethylene propylene rubber has been selected as a candidate for replacement of nitrile rubber in the SRP tritium facilities. A specification for flange gasket material has been developed for ethylene propylene such that its mechanical properties are similar to those of nitrile rubber. In-process testing of ethylene propylene and nitrile gaskets will be conducted in the tritium facilities under identical exposure conditions

  8. Effluent Treatment Facility tritium emissions monitoring

    International Nuclear Information System (INIS)

    Dunn, D.L.

    1991-01-01

    An Environmental Protection Agency (EPA) approved sampling and analysis protocol was developed and executed to verify atmospheric emissions compliance for the new Savannah River Site (SRS) F/H area Effluent Treatment Facility. Sampling equipment was fabricated, installed, and tested at stack monitoring points for filtrable particulate radionuclides, radioactive iodine, and tritium. The only detectable anthropogenic radionuclides released from Effluent Treatment Facility stacks during monitoring were iodine-129 and tritium oxide. This paper only examines the collection and analysis of tritium oxide

  9. Tritium radioluminescent devices, Health and Safety Manual

    International Nuclear Information System (INIS)

    Traub, R.J.; Jensen, G.A.

    1995-06-01

    This document consolidates available information on the properties of tritium, including its environmental chemistry, its health physics, and safe practices in using tritium-activated RL lighting. It also summarizes relevant government regulations on RL lighting. Chapters are divided into a single-column part, which provides an overview of the topic for readers simply requiring guidance on the safety of tritium RL lighting, and a dual-column part for readers requiring more technical and detailed information

  10. Long-term observation of tritium in pine needles near nuclear facilities

    International Nuclear Information System (INIS)

    Inoue, Y.; Miyamoto, K.T.; Iwakura, T.; Jin, S.

    1988-01-01

    An interest has been focussed on tissue bound tritium (TBT) in foods, because it may be directly assimilated in the bound compartment of tissues, and increase cumulative total body dose. Transfer from environmental tritiated water to the tissue bound fraction in plants has been investigated through many laboratories and relatively lower percentage fixation was suggested. On the other hand, analysis of various kind of environmental samples which were considered to be affected by fallout tritium only showed high specific activity ratio of TBT to tissue water tritium (TWT). This phenomenon had been attributed to either: long retention of tritium previously incorporated in the soil during the period of maximum fallout; or an incorporation of high specific activity elemental tritium in the atmosphere into the soil microbes and plants. More studies have to be performed in the environment as well as in the laboratories on the behaviour of TBT in different types ecosystems in order to solve this problem. Therefore, a long-term study was conducted on the behaviour of TBT and TWT in plants in a location which had been affected mainly by tritiated vapour discharged into the atmosphere

  11. Tritium inventory control--the experience with DT tokamaks and its relevance for future machines

    International Nuclear Information System (INIS)

    Bell, A.C.; Gentile, C.A.; Laesser, R.L.K.; Coad, J.P.

    2003-01-01

    At present, the commercial use of tritium is relatively small scale. The main source of supply is as a by-product of heavy water moderated fission reactors and the products are mainly discrete sources or tracers with activity typically in the GBq range. There are in general no restrictions on the use of tritium other than those, which would normally apply to the use of radioactive material. The future use of tritium as intermediate fuel for a fusion power plant series will involve an increase by several orders of magnitude in the industrial use of tritium and may increase concerns relating to safety, transport and waste disposal. In addition, the use of tritium in fusion power will be unable to be satisfied by current sources of supply and tritium production in future fusion power plants will be essential for the operation of the plants as well as for the start of new ones. Power plant studies have, however, shown that these issues can be satisfactorily addressed. In addition the values for clearance of tritiated materials in a number of countries are consistent with the low environmental impact of disposal of tritiated waste. There are, however, many practical operational and regulatory problems, which will need to be solved in the context of the experimental programmes. The current regulations for control and accountancy of tritium inventory, as applied internationally and in specific countries, are reviewed and their influence on the DT fuel cycle considered. The effect of safety case limits on the need for control of tritium inventory in TFTR, JET and ITER is analysed. The sensitivity of the fuel cycle to tritium inventory is considered. The experience of controlling tritium inventory in TFTR and JET is reviewed and the latest results from JET presented. This takes into account the limits and constraints, the differing requirements for tritium processing, in-vessel retention, the needs for waste management and decommissioning including detritiation, and

  12. Tritium in precipitation of Vostok (Antarctica): conclusions on the tritium latitude effect.

    Science.gov (United States)

    Hebert, Detlef

    2011-09-01

    During the Antarctic summer of 1985 near the Soviet Antarctic station Vostok, firn samples for tritium measurements were obtained down to a depth of 2.40 m. The results of the tritium measurements are presented and discussed. Based on this and other data, conclusions regarding the tritium latitude effect are derived.

  13. Development of tritium handing technology(II)

    International Nuclear Information System (INIS)

    Chung, H. S.; Ahn, D. H.; Kim, K. R.; Yook, D. S.; Song, K. M.; Son, S. H.; Lee, K. J.; Jung, H. Y.; Song, M. C.

    2004-02-01

    The buildup rate of tritium in heavy water moderator and coolant of pressurized heavy water reactors in Wolsong Nuclear Power Plant is about 4MCi/a. The control of tritium is of increasing concern to the power reactor industry and general public in Korea. Metal tritides have the advantage of significantly decreasing the volume required to store tritium without increasing the pressure of storage vessel. Titanium hydride was safely used for the long-term storage of tritium. The experimental thermodynamic P-C-T data show that titanium soaks up hydrogen isotope gas at ambient temperature and modest pressures

  14. Tritium resources available for fusion reactors

    Science.gov (United States)

    Kovari, M.; Coleman, M.; Cristescu, I.; Smith, R.

    2018-02-01

    The tritium required for ITER will be supplied from the CANDU production in Ontario, but while Ontario may be able to supply 8 kg for a DEMO fusion reactor in the mid-2050s, it will not be able to provide 10 kg at any realistic starting time. The tritium required to start DEMO will depend on advances in plasma fuelling efficiency, burnup fraction, and tritium processing technology. It is in theory possible to start up a fusion reactor with little or no tritium, but at an estimated cost of 2 billion per kilogram of tritium saved, it is not economically sensible. Some heavy water reactor tritium production scenarios with varying degrees of optimism are presented, with the assumption that only Canada, the Republic of Korea, and Romania make tritium available to the fusion community. Results for the tritium available for DEMO in 2055 range from zero to 30 kg. CANDU and similar heavy water reactors could in theory generate additional tritium in a number of ways: (a) adjuster rods containing lithium could be used, giving 0.13 kg per year per reactor; (b) a fuel bundle with a burnable absorber has been designed for CANDU reactors, which might be adapted for tritium production; (c) tritium production could be increased by 0.05 kg per year per reactor by doping the moderator with lithium-6. If a fusion reactor is started up around 2055, governments in Canada, Argentina, China, India, South Korea and Romania will have the opportunity in the years leading up to that to take appropriate steps: (a) build, refurbish or upgrade tritium extraction facilities; (b) extend the lives of heavy water reactors, or build new ones; (c) reduce tritium sales; (d) boost tritium production in the remaining heavy water reactors. All of the alternative production methods considered have serious economic and regulatory drawbacks, and the risk of diversion of tritium or lithium-6 would also be a major concern. There are likely to be serious problems with supplying tritium for future

  15. Development of tritium handing technology(II)

    Energy Technology Data Exchange (ETDEWEB)

    Chung, H. S.; Ahn, D. H.; Kim, K. R. [KAERI, Taejon (Korea, Republic of); Yook, D. S.; Song, K. M.; Son, S. H. [KEPRI, Taejon (Korea, Republic of); Lee, K. J.; Jung, H. Y.; Song, M. C. [KAIST, Taejon (Korea, Republic of)

    2004-02-01

    The buildup rate of tritium in heavy water moderator and coolant of pressurized heavy water reactors in Wolsong Nuclear Power Plant is about 4MCi/a. The control of tritium is of increasing concern to the power reactor industry and general public in Korea. Metal tritides have the advantage of significantly decreasing the volume required to store tritium without increasing the pressure of storage vessel. Titanium hydride was safely used for the long-term storage of tritium. The experimental thermodynamic P-C-T data show that titanium soaks up hydrogen isotope gas at ambient temperature and modest pressures.

  16. Measurement of tritium concentration in urine

    International Nuclear Information System (INIS)

    Sekiyama, Shigenobu; Deshimaru, Takehide

    1979-01-01

    Concerning the safety management of the advanced thermal reactor ''Fugen'', the internal exposure management for tritium is important, because heavy water is used as the moderator in the reactor, and tritium is produced in the heavy water. Tritium is the radioactive nuclide with the maximum β-ray energy of 18 keV, and the radiation exposure is limited to the internal exposure in human bodies, as tritium is taken in through the skin and by breathing. The tritium concentration in urine of the operators of the Fugen plant was measured. As for tritium measurement, the analysis of raw urine, the analysis after passing through mixed ion exchange resin and the analysis after distillation are applied. The scintillator, the liquid scintillation counter, the ion exchange resin and the distillator are introduced. The preliminary survey was conducted on the urine sample, the scintillator the calibration, etc. The measuring condition, the measurement of efficiency, and the limitation of detection with various background are explained, with the many experimental data and the calculating formula. Concerning the measured tritium concentration in urine, the tritium concentrations in distilled urine, raw urine and the urine refined with ion exchange resin were compared, and the correlation formulae are presented. The actual tritium concentration value in urine was less than 50 pci/ml. The measuring methods of raw urine and the urine refined with ion exchange resin are adequate as they are quick and accurate. (Nakai, Y.)

  17. Tritium proof-of-principle pellet injector

    International Nuclear Information System (INIS)

    Fisher, P.W.

    1991-07-01

    The tritium proof-of-principle (TPOP) experiment was designed and built by Oak Ridge National Laboratory (ORNL) to demonstrate the formation and acceleration of the world's first tritium pellets for fueling of future fusion reactors. The experiment was first used to produce hydrogen and deuterium pellets at ORNL. It was then moved to the Tritium Systems Test Assembly at Los Alamos National Laboratory for the production of tritium pellets. The injector used in situ condensation to produce cylindrical pellets in a 1-m-long, 4-mm-ID barrel. A cryogenic 3 He separator, which was an integral part of the gun assembly, was capable of lowering 3 He levels in the feed gas to <0.005%. The experiment was housed to a glovebox for tritium containment. Nearly 1500 pellets were produced during the course of the experiment, and about a third of these were pure tritium or mixtures of deuterium and tritium. Over 100 kCi of tritium was processed through the experiment without incident. Tritium pellet velocities of 1400 m/s were achieved with high-pressure hydrogen propellant. The design, operation, and results of this experiment are summarized. 34 refs., 44 figs., 3 tabs

  18. Tritium stripping by a catalytic exchange stripper

    International Nuclear Information System (INIS)

    Heung, L.K.; Gibson, G.W.; Ortman, M.S.

    1991-01-01

    A catalytic exchange process for stripping elemental tritium from gas streams has been demonstrated. The process uses a catalyzed isotopic exchange reaction between tritium in the gas phase and protium or deuterium in the solid phase on alumina. The reaction is catalyzed by platinum deposited on the alumina. The process has been tested with both tritium and deuterium. Decontamination factors (ration of inlet and outlet tritium concentrations) as high as 1000 have been achieved, depending on inlet concentration. The test results and some demonstrated applications are presented

  19. Tritium in the environment: origins and analysis

    International Nuclear Information System (INIS)

    Baglan, N.

    2009-01-01

    The author recalls the chemical reactions at the origin of tritium formation, that tritium has been introduced in the atmosphere by nuclear tests, and that it is now produced by nuclear reactors. He also outlines that tritium is mainly released in waters (oceans, seas, rivers) or in the atmosphere. Some high concentrations may therefore occur. He discusses measurements of activity in rain waters and surface waters, and outlines the impact of the end of atmospheric nuclear tests. He discusses the technical challenges of low level tritium analysis and activity measurement

  20. Driver's behavioural changes with new intelligent transport system interventions at railway level crossings--A driving simulator study.

    Science.gov (United States)

    Larue, Grégoire S; Kim, Inhi; Rakotonirainy, Andry; Haworth, Narelle L; Ferreira, Luis

    2015-08-01

    Improving safety at railway level crossings is an important issue for the Australian transport system. Governments, the rail industry and road organisations have tried a variety of countermeasures for many years to improve railway level crossing safety. New types of intelligent transport system (ITS) interventions are now emerging due to the availability and the affordability of technology. These interventions target both actively and passively protected railway level crossings and attempt to address drivers' errors at railway crossings, which are mainly a failure to detect the crossing or the train and misjudgement of the train approach speed and distance. This study aims to assess the effectiveness of three emerging ITS that the rail industry considers implementing in Australia: a visual in-vehicle ITS, an audio in-vehicle ITS, as well as an on-road flashing beacons intervention. The evaluation was conducted on an advanced driving simulator with 20 participants per trialled technology, each participant driving once without any technology and once with one of the ITS interventions. Every participant drove through a range of active and passive crossings with and without trains approaching. Their speed approach of the crossing, head movements and stopping compliance were measured. Results showed that driver behaviour was changed with the three ITS interventions at passive crossings, while limited effects were found at active crossings, even with reduced visibility. The on-road intervention trialled was unsuccessful in improving driver behaviour; the audio and visual ITS improved driver behaviour when a train was approaching. A trend toward worsening driver behaviour with the visual ITS was observed when no trains were approaching. This trend was not observed for the audio ITS intervention, which appears to be the ITS intervention with the highest potential for improving safety at passive crossings. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Panorama 2015 - Changes in French behaviour in terms of transport: generational effect and new mobility services

    International Nuclear Information System (INIS)

    Chevalier, Amandine; Lantz, Frederic

    2014-11-01

    Analysis of the daily mobility of French households reveals some changes in their use of the different modes of transport available to them. While use of the private car is still predominant, the use of other transport modes is changing, depending on the socio-economic characteristics of households and areas of residence. New mobility services such as car-pooling or car sharing now complement the transport facilities available to individuals. (authors)

  2. Determination of tritium by counting; Dosage du tritium par comptage

    Energy Technology Data Exchange (ETDEWEB)

    Schott, R.; Froment, G.; Pinson, J.; Genty, C. [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1968-07-01

    Ionisation chamber assay of tritium in any gaseous mixture is a simple, fast and accurate method. We used the method of relative determination by comparison to a standard rather than the method of absolute assay in which case the constants are known with too little accuracy. The efficiency of the chamber was studied in connection to the pressure inside the chamber and its total volume. The calibration is linear in the range we are taking into account (1 to 80 millicuries). The reproducibility of the method is good: 13 runs gave a coefficient of variation of 1.6 per cent. The relative accuracy was found equal to {+-} 1.3 per cent. To end the paper, we describe in detail the apparatus and the ways of proceedings. (authors) [French] Le comptage du tritium par chambre d'ionisation est une methode simple, rapide et precise pour determiner la teneur en tritium d'un melange gazeux quelconque. Nous avons prefere utiliser la methode de determination relative par rapport a un etalon car, dans le cas d'une determination absolue, les constantes sont connues avec une trop grande incertitude. L'efficacite de la chambre a ete etudiee en fonction de la variation de la pression d'argon a l'interieur de la chambre et du volume total, de cette derniere. L'etalonnage s'est revele lineaire dans le domaine de mesures qui nous interessaient (1 a 80 millicuries). La reproductibillte de la methode est tres bonne, le coefficient de variation pour une serie de 13 essais etant de 1,6 pour cent, quant a la precision relative, elle a ete evaluee a {+-} 1,3 pour cent. Pour terminer, nous donnons une description detaillee de l'appareillage utilise et du mode operatoire suivi. (auteurs)

  3. The effective cost of tritium for tokamak fusion power reactors with reduced tritium production systems

    International Nuclear Information System (INIS)

    Gilligan, J.G.; Evans, K.

    1983-01-01

    If sufficient tritium cannot be produced and processed in tokamak blankets then at least two alternatives are possible. Tritium can be purchased; or reactors with reduced tritium (RT) content in the plasma can be designed. The latter choice may require development of magnet technology etc., but the authors show that the impact on the cost-of-electricity may be mild. Cost tradeoffs are compared to the market value of tritium. Adequate tritium production in fusion blankets is preferred, but the authors show there is some flexibility in the deployment of fusion if this is not possible

  4. Tritium sorption on protective coatings for concrete

    International Nuclear Information System (INIS)

    Miller, J.M.; Senohrabek, J.A.; Allsop, P.A.

    1992-11-01

    Because of the high sorption level of tritium on unprotected concrete, a program to examine the effectiveness of various concrete coatings and sealants in reducing tritium sorption was undertaken, and various exposure conditions were examined. Coatings of epoxy, polyurethane, bituminous sealant, bituminous sealant covered with polyvinylidene chloride wrap, alkyd paint, and sodium silicate were investigated with tritium (HTO) vapor concentration, humidity and contact time being varied. An exposure to HT was also carried out, and the effect of humidity on the tritium desorption rate was investigated. The relative effectiveness of the coatings was in the order of bituminous sealant + wrap > bituminous sealant > solvent-based epoxy > 100%-solids epoxy > alkyd paint > sodium silicate. The commercially available coatings for concrete resulted in tritium sorption being reduced to less than 7% of unprotected concrete. This was improved to ∼0.1% with the use of the Saran wrap (polyvinylidene chloride). The amount of tritium sorbed was proportional to tritium concentration. The total tritium sorbed decreased with an increase in humidity. A saturation effect was observed with increasing exposure time for both the coated and unprotected samples. Under the test conditions, complete saturation was not achieved within the maximum 8-hour contact time, except for the solvent-based epoxy. The desorption rate increased with a higher-humidity air purge stream. HT desorbed more rapidly than HTO, but the amount sorbed was smaller. The experimental program showed that HTO sorption by concrete can be significantly reduced with the proper choice of coating. However, tritium sorption on concrete and proposed coatings will continue to be a concern until the effects of the various conditions that affect the adsorption and desorption of tritium are firmly established for both chronic and acute tritium release conditions. Material sorption characteristics must also be considered in

  5. The dynamics of tritium - including OBT- in the aquatic food chain

    International Nuclear Information System (INIS)

    Galeriu, D.; Heling, R.; Melintescu, A.

    2005-01-01

    Full text: Tritiated water spills by nuclear installations result in uptake in aquatic organisms. The radionuclide uptake model BURN (developed by NRG, modified), considers not only tritium as tritiated water (HTO) but also the conversion into organically bound tritium (OBT). Comparison with the original BURN model showed that the modified model gave more realistic results in terms of concentration levels, and consequently for dose assessment as result of ingestion of fishery products. For more accurate modelling, seasonal effects and half-life estimates as a function of body weight and water temperature must be taken into account. A first attempt is given, although limited empirical data gives reason to further investigation of this significant effect. At present, there are no dynamic models which take into account the metabolic regulation of tritium in plants and animals. In the RODOS system for instance, developed within the EC-project in the past decade, in biological uptake models such as LAKECO (freshwater) and BURN (marine environment) tritium is treated as other radionuclides. Previously the BURN model was modified in order to cope with the metabolic regulation of hydrogen and tritium. In this paper the further development considering seasonality and a metabolic model for OBT loss rate in fish is presented. The importance of considering the specificity of the tritium metabolic pathways was illustrated by comparing the tritium uptake model with the initial BURN model, in which the behaviour of tritium is not different from other radionuclides. Using tritium model, the total tritium concentration in the organism decreased in proportion to the decrease in the river water, to a level where OBT in fish was predominant and slowly varying. Note the difference in the OBT concentration between a winter and a summer release (temperature effect). BURN predicted the integrated total tritium concentration in fish for the first year more than 200 times higher than the

  6. Vertical distribution of tritium in core sediment of Mumbai Harbour Bay

    International Nuclear Information System (INIS)

    Rupali, C.K.; Joshi, Vikram; Jha, S.K.; Tripathi, R.M.; Sonali, B.; Priyanka, R.

    2014-01-01

    In the past few years there has been an increasing interest in the study of behavior of tritium in the environment, worldwide many countries have initiated monitoring of organically bound tritium in the environmental samples as part of their radiological assessments. Tritium ( 3 H) is ubiquitous in the aquatic environment and has a various sources of origin. It is transported to the earth's surface via hydrological cycle. 3 H is produced in variety of processes in nuclear power plants. Discharges to aquatic environment from these establishment results in locally enhanced water concentrations. Levels of 3 H have been further elevated due to atmospheric weapons testing between 1952 and 1962. Recent studies have demonstrated significant accumulation of tritium in both organic-rich sediments and food chain. The present study describes the vertical profile of tritium distribution in core sediment collected from Mumbai Harbour Bay (MHB). This will help in better understanding of the biogeochemical behavior and ecological impacts of tritium in the sediment

  7. Means of transportation and its effect on eye care seeking behaviour ...

    African Journals Online (AJOL)

    Results: A total of 348 patients interviewed were found to use various means of transportation when seeking western medical or traditional medical assistance. Some had to use several modes of transport in order to arrive at the outreach eye clinic. Patients were seen from six districts in Giwa Local government Area.

  8. Transport behaviour and diffusion of telematics: a conceptual framework and empirical application

    NARCIS (Netherlands)

    Pepping, G.; Nijkamp, P.

    1995-01-01

    The potential impacts that may be expected from new information and telecommunicationsystems applied to transport are considerable. However, as is the case with anynew technological innovation, at the basis of success of transport telematics lies theacceptance by potential users, which suggests that

  9. International comparison of computer codes for modelling the dispersion and transfer of tritium released to the atmosphere

    International Nuclear Information System (INIS)

    Russell, S.B.; Kempe, T.F.; Donnelly, K.J.

    1985-05-01

    Computer codes for modelling the dispersion and transfer of tritium released to the atmosphere were compared. The codes originated from Canada, the United States, Sweden and Japan. The comparisons include acute and chronic emissions of tritiated water vapour or elemental tritium from a hypothetical nuclear facility. Individual and collective doses to the population within 100 km of the site were calculated. The discrepancies among the code predictions were about one order of magnitude for the HTO emissions but were significantly more varied for the HT emissions. Codes that did not account for HT to HTO conversion and cycling of tritium in the environment predicted doses that were several orders of magnitude less than codes that incorporate this feature into the model. A field experiment consisting of the release of tritium gas and subsequent measurements of tritium concentrations in the environment has been recommended to validate the tritium transport models and code predictions and to refine the values of key parameters in the models. It is further recommended that the results from a field experiment be used in a follow-up code validation study to confirm which conceptual model and derived computer code provides the best representation of tritium transport in the real system

  10. Complexation of novel diglycolamide functionalized calix[4]arenes: unusual extraction behaviour, transport, and fluorescence studies

    NARCIS (Netherlands)

    Mohapatra, P.K.; Iqbal, M.; Raut, D.R.; Verboom, Willem; Huskens, Jurriaan

    2012-01-01

    Three diglycolamide functionalized calix[4]arenes (calix[4]-nDGA) were synthesized and evaluated for their extraction behaviour towards lanthanide/actinide ions. Exceptionally high DAm and DPu values indicate these radiotoxic elements can be selectively removed from nuclear waste solutions.

  11. The requirement for proper storage of nuclear and related decommissioning samples to safeguard accuracy of tritium data.

    Science.gov (United States)

    Kim, Daeji; Croudace, Ian W; Warwick, Phillip E

    2012-04-30

    Large volumes of potentially tritium-contaminated waste materials are generated during nuclear decommissioning that require accurate characterisation prior to final waste sentencing. The practice of initially determining a radionuclide waste fingerprint for materials from an operational area is often used to save time and money but tritium cannot be included because of its tendency to be chemically mobile. This mobility demands a specific measurement for tritium and also poses a challenge in terms of sampling, storage and reliable analysis. This study shows that the extent of any tritium redistribution during storage will depend on its form or speciation and the physical conditions of storage. Any weakly or moderately bound tritium (e.g. adsorbed water, waters of hydration or crystallisation) may be variably lost at temperatures over the range 100-300 °C whereas for more strongly bound tritium (e.g. chemically bound or held in mineral lattices) the liberation temperature can be delayed up to 800 °C. For tritium that is weakly held the emanation behaviour at different temperatures becomes particularly important. The degree of (3)H loss and cross-contamination that can arise after sampling and before analysis can be reduced by appropriate storage. Storing samples in vapour tight containers at the point of sampling, the use of triple enclosures, segregating high activity samples and using a freezer all lead to good analytical practice. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Tritium removal using vanadium hydride

    International Nuclear Information System (INIS)

    Hill, F.B.; Wong, Y.W.; Chan, Y.N.

    1978-01-01

    The results of an initial examination of the feasibility of separation of tritium from gaseous protium-tritium mixtures using vanadium hydride in cyclic processes is reported. Interest was drawn to the vanadium-hydrogen system because of the so-called inverse isotope effect exhibited by this system. Thus the tritide is more stable than the protide, a fact which makes the system attractive for removal of tritium from a mixture in which the light isotope predominates. The initial results of three phases of the research program are reported, dealing with studies of the equilibrium and kinetics properties of isotope exchange, development of an equilibrium theory of isotope separation via heatless adsorption, and experiments on the performance of a single heatless adsorption stage. In the equilibrium and kinetics studies, measurements were made of pressure-composition isotherms, the HT--H 2 separation factors and rates of HT--H 2 exchange. This information was used to evaluate constants in the theory and to understand the performance of the heatless adsorption experiments. A recently developed equilibrium theory of heatless adsorption was applied to the HT--H 2 separation using vanadium hydride. Using the theory it was predicted that no separation would occur by pressure cycling wholly within the β phase but that separation would occur by cycling between the β and γ phases and using high purge-to-feed ratios. Heatless adsorption experiments conducted within the β phase led to inverse separations rather than no separation. A kinetic isotope effect may be responsible. Cycling between the β and γ phases led to separation but not to the predicted complete removal of HT from the product stream, possibly because of finite rates of exchange. Further experimental and theoretical work is suggested which may ultimately make possible assessment of the feasibility and practicability of hydrogen isotope separation by this approach

  13. Environmental tritium monitoring around Tokai Reprocessing Plant

    International Nuclear Information System (INIS)

    Yamato, A.

    1982-01-01

    The environmental tritium monitoring in the sea near Tokai Reprocessing Plant has been performed since 1977, the year of having started the hot test operation of the plant. On the other hand, atmospheric tritium monitoring was started almost at the same time as a research program instead of a routine program. This paper is a review for tritium monitoring in the sea and in the air around the Tokai Reprocessing Plant. The plant is located in Tokai Village, Ibaraki Prefecture, on the Pacific coast. It is based on the Purex process, and the nominal capacity is 210 tons per year. Around the TRP, there are four uranium fabrication facilities, five research reactors, two power reactors and other research facilities. About 173,000 inhabitants are within 10 km range from the plant. The authorized discharge limit of tritium is 200 Ci per day and 51,100 Ci per year in the sea. That in the atmosphere is 50 Ci per day and about 15,000 Ci per year. The tritium from the TRP was discharged mainly into the sea. The sea water samples were distilled, and the tritium concentration was measured by liquid scintillation counting. During three years of the hot operation of TRP, discharged tritium was about 7,000 Ci into the sea and about 140 Ci into the atmosphere. The tritium level has been maintained, and its significant increase was not observed. (Kako, I.)

  14. Enantiospecific tritium labeling of 28-homocastasterone

    Czech Academy of Sciences Publication Activity Database

    Elbert, Tomáš; Patil, Mahadeo Rajshekhar; Marek, Aleš

    2017-01-01

    Roč. 60, č. 3 (2017), s. 176-182 ISSN 0362-4803 R&D Projects: GA AV ČR IAA400550801 Institutional support: RVO:61388963 Keywords : 28-homocastasterone * brassinosteroids * enantiospecific reaction * tritium dehalogenation * tritium labeling Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 1.745, year: 2016

  15. Tritium labeling of detonation nanodiamonds.

    Science.gov (United States)

    Girard, Hugues A; El-Kharbachi, Abdelouahab; Garcia-Argote, Sébastien; Petit, Tristan; Bergonzo, Philippe; Rousseau, Bernard; Arnault, Jean-Charles

    2014-03-18

    For the first time, the radioactive labeling of detonation nanodiamonds was efficiently achieved using a tritium microwave plasma. According to our measurements, the total radioactivity reaches 9120 ± 120 μCi mg(-1), with 93% of (3)H atoms tightly bonded to the surface and up to 7% embedded into the diamond core. Such (3)H doping will ensure highly stable radiolabeled nanodiamonds, on which surface functionalization is still allowed. This breakthrough opens the way to biodistribution and pharmacokinetics studies of nanodiamonds, while this approach can be scalable to easily treat bulk quantities of nanodiamonds at low cost.

  16. Effects of kinetic and transport phenomena on thermal explosion and oscillatory behaviour in a spherical reactor with mixed convection.

    Science.gov (United States)

    Gonçalves de Azevedo, Filipa; Griffiths, John F; Cardoso, Silvana S S

    2014-11-14

    Thermal explosions are often influenced by the complex interaction between transport and reaction phenomena. In particular, reactant consumption can promote safer, non-explosive operation conditions of combustion systems. However, in liquids or gases, the presence of forced convection can affect the behaviour of a system, instigating oscillations in the temperature, reactant concentration and velocity fields. This work describes the effect of reactant consumption on a simple, one-step, exothermic reaction occurring in a spherical reactor with both forced and natural convection, by means of numerical simulations. Regime diagrams characterised by ratios of timescales for each transport and reaction phenomena are presented and the explosion boundary is represented for several forced convection and reaction consumption intensities. Special attention is given to the oscillatory behaviour observed for moderate forced convection and oscillatory regions are represented on the regime diagrams. Parametric conditions for this new oscillatory regime are identified by extending the criticality condition developed by Frank-Kamenetskii for the effect of reactant consumption in diffusive systems to include the effects of both natural and forced convection.

  17. Methane generated from graphite--tritium interaction

    International Nuclear Information System (INIS)

    Coffin, D.O.; Walthers, C.R.

    1979-01-01

    When hydrogen isotopes are separated by cryogenic distillation, as little as 1 ppM of methane will eventually plug the still as frost accumulates on the column packings. Elemental carbon exposed to tritium generates methane spontaneously, and yet some dry transfer pumps, otherwise compatible with tritium, convey the gas with graphite rotors. This study was to determine the methane production rate for graphite in tritium. A pump manufacturer supplied graphite samples that we exposed to tritium gas at 0.8 atm. After 137 days we measured a methane synthesis rate of 6 ng/h per cm 2 of graphite exposed. At this rate methane might grow to a concentration of 0.01 ppM when pure tritium is transferred once through a typical graphite--rotor transfer pump. Such a low methane level will not cause column blockage, even if the cryogenic still is operated continuously for many years

  18. The organic tritium in the environment

    International Nuclear Information System (INIS)

    Kirchmann, R.

    1979-01-01

    Sources, organization process, and biological availability of organic tritium released in the environment, transfer of organic tritium in the environment from methane or soil to plants and from food to mammals, transfer of tritium in aquatic ecosystems, and dose to man resulting of the ingestion of tritiated food were reviewed and discussed. Some data about transfer of organic tritium in terrestrial and aquatic ecosystems reported by literatures were summarized and were supplied with recent data on biological accumulation of organic tritium in the food chain. It was stressed that more research must be done in future because data available were still insufficient. Last, some research programs in progress or planned were stated. (Tsunoda, M.)

  19. Handling of tritium-bearing wastes

    International Nuclear Information System (INIS)

    1981-01-01

    The generation of nuclear power and reprocessing of nuclear fuel results in the production of tritium and the possible need to control the release of tritium-contaminated effluents. In assessing the need for controls, it is necessary to know the production rates of tritium at different nuclear facilities, the technologies available for separating tritium from different gaseous and liquid streams, and the methods that are satisfactory for storage and disposal of tritiated wastes. The intention in applying such control technologies and methods is to avoid undesirable effects on the environment, and to reduce the radiation burden on operational personnel and the general population. This technical report is a result of the IAEA Technical Committee Meeting on Handling of Tritium-bearing Effluents and Wastes, which was held in Vienna, 4 - 8 December 1978. It summarizes the main topics discussed at the meeting and appends the more detailed reports on particular aspects that were prepared for the meeting by individual participants

  20. DOE handbook: Tritium handling and safe storage

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    The DOE Handbook was developed as an educational supplement and reference for operations and maintenance personnel. Most of the tritium publications are written from a radiological protection perspective. This handbook provides more extensive guidance and advice on the null range of tritium operations. This handbook can be used by personnel involved in the full range of tritium handling from receipt to ultimate disposal. Compliance issues are addressed at each stage of handling. This handbook can also be used as a reference for those individuals involved in real time determination of bounding doses resulting from inadvertent tritium releases. This handbook provides useful information for establishing processes and procedures for the receipt, storage, assay, handling, packaging, and shipping of tritium and tritiated wastes. It includes discussions and advice on compliance-based issues and adds insight to those areas that currently possess unclear DOE guidance.

  1. DOE handbook: Tritium handling and safe storage

    International Nuclear Information System (INIS)

    1999-03-01

    The DOE Handbook was developed as an educational supplement and reference for operations and maintenance personnel. Most of the tritium publications are written from a radiological protection perspective. This handbook provides more extensive guidance and advice on the null range of tritium operations. This handbook can be used by personnel involved in the full range of tritium handling from receipt to ultimate disposal. Compliance issues are addressed at each stage of handling. This handbook can also be used as a reference for those individuals involved in real time determination of bounding doses resulting from inadvertent tritium releases. This handbook provides useful information for establishing processes and procedures for the receipt, storage, assay, handling, packaging, and shipping of tritium and tritiated wastes. It includes discussions and advice on compliance-based issues and adds insight to those areas that currently possess unclear DOE guidance

  2. Disposal of tritium-exposed metal hydrides

    International Nuclear Information System (INIS)

    Nobile, A.; Motyka, T.

    1991-01-01

    A plan has been established for disposal of tritium-exposed metal hydrides used in Savannah River Site (SRS) tritium production or Materials Test Facility (MTF) R ampersand D operations. The recommended plan assumes that the first tritium-exposed metal hydrides will be disposed of after startup of the Solid Waste Disposal Facility (SWDF) Expansion Project in 1992, and thus the plan is consistent with the new disposal requiremkents that will be in effect for the SWDF Expansion Project. Process beds containing tritium-exposed metal hydride powder will be disposed of without removal of the powder from the bed; however, disposal of tritium-exposed metal hydride powder that has been removed from its process vessel is also addressed

  3. Uptake of atmospheric tritium by market foods

    International Nuclear Information System (INIS)

    Inoue, Y.; Tanaka-Miyamoto, K.; Iwakura, T.

    1992-01-01

    In this paper uptake of tritium by market foods from tritiated water vapor in the air is investigated using cereals and beans purchased in Deep River, Canada. The concentrations of tissue free water tritium (TFWT) and organically bound tritium (OBT) range from 12 to 79% and from 10 to 38% respectively, of that estimated for atmospheric water vapor of the sampling month. The specific activity ratios of OBT to TFWT were constant for cereals, but variable for beans. The elevated OBT was shown to be the result of isotopic exchange of labile hydrogen by the fact that washing the foods with tritium free-water reduced their tritium contents to levels characteristic of their production sites

  4. Experiences with decontaminating tritium-handling apparatus

    International Nuclear Information System (INIS)

    Maienschein, J.L.; Garcia, F.; Garza, R.G.; Kanna, R.L.; Mayhugh, S.R.; Taylor, D.T.

    1992-01-01

    Tritium-handling apparatus has been decontaminated as part of the downsizing of the LLNL Tritium Facility. Two stainless-steel glove boxes that had been used to process lithium deuteride-tritide (LiDT) slat were decontaminated using the Portable Cleanup System so that they could be flushed with room air through the facility ventilation system. In this paper the details on the decontamination operation are provided. A series of metal (palladium and vanadium) hydride storage beds have been drained of tritium and flushed with deuterium, in order to remove as much tritium as possible. The bed draining and flushing procedure is described, and a calculational method is presented which allows estimation of the tritium remaining in a bed after it has been drained and flushed. Data on specific bed draining and flushing are given

  5. Management of Tritium in European Spallation Source

    DEFF Research Database (Denmark)

    Ene, Daniela; Andersson, Kasper Grann; Jensen, Mikael

    2015-01-01

    The European Spallation Source (ESS) will produce tritium via spallation and activation processes during operational activities. Within the location of ESS facility in Lund, Sweden site it is mandatory to demonstrate that the management strategy of the produced tritium ensures the compliance...... with the country regulation criteria. The aim of this paper is to give an overview of the different aspects of the tritium management in ESS facility. Besides the design parameter study of the helium coolant purification system of the target the consequences of the tritium releasing into the environment were also...... analyzed. Calculations shown that the annual release of tritium during the normal operations represents a small fraction from the estimated total dose. However, more refined calculations of migration of activated-groundwater should be performed for higher hydraulic conductivities, with the availability...

  6. Recent environmental tritium levels in Japan

    International Nuclear Information System (INIS)

    Iwakura, T.; Inoue, Y.; Tanaka, K.; Kasida, Y.

    1982-01-01

    Data of the tritium surveillance program are summarized for the period of 1967 through 1980. Samples of surface water, tap water, coastal sea water and ground water were collected from environs of commercial nuclear power plants and nuclear facilities, and were analyzed by liquid scintillation counting. Although the results show some differences in tritium concentrations in water samples from various part of the country, there is a general tendency of the concentration in surface waters to decline as a function of time. This implies that environmental waters in Japan generally have not been influenced by the discharged effluents of the facilities or the stations with regard to tritium contamination and that the tritium content of precipitation still plays the dominant role in reflecting annual variation of tritium concentration in surface waters. (J.P.N.)

  7. Physics of high performance deuterium-tritium plasmas in TFTR

    International Nuclear Information System (INIS)

    McGuire, K.M.; Batha, S.

    1996-11-01

    During the past two years, deuterium-tritium (D-T) plasmas in the Tokamak Fusion Test Reactor (TFTR) have been used to study fusion power production, isotope effects associated with tritium fueling, and alpha-particle physics in several operational regimes. The peak fusion power has been increased to 10.7 MW in the supershot mode through the use of increased plasma current and toroidal magnetic field and extensive lithium wall conditioning. The high-internal-inductance (high-I i ) regime in TFTR has been extended in plasma current and has achieved 8.7 MW of fusion power. Studies of the effects of tritium on confinement have now been carried out in ohmic, NBI- and ICRF- heated L-mode and reversed-shear plasmas. In general, there is an enhancement in confinement time in D-T plasmas which is most pronounced in supershot and high-I i discharges, weaker in L-mode plasmas with NBI and ICRF heating and smaller still in ohmic plasmas. In reversed-shear discharges with sufficient deuterium-NBI heating power, internal transport barriers have been observed to form, leading to enhanced confinement. Large decreases in the ion heat conductivity and particle transport are inferred within the transport barrier. It appears that higher heating power is required to trigger the formation of a transport barrier with D-T NBI and the isotope effect on energy confinement is nearly absent in these enhanced reverse-shear plasmas. Many alpha-particle physics issues have been studied in the various operating regimes including confinement of the alpha particles, their redistribution by sawteeth, and their loss due to MHD instabilities with low toroidal mode numbers. In weak-shear plasmas, alpha-particle destabilization of a toroidal Alfven eigenmode has been observed

  8. Tritium behavior in an aquatic ecosystem

    International Nuclear Information System (INIS)

    Komatsu, K.

    1982-01-01

    Tritium behavior in aquatic organisms through a model food chain was investigated. In this model food chain, tritium in water reaches bacteria or Japanese killifish via diatoms and brine shrimps. Tritium accumulation in these organisms as organic bound form was expressed as the R value which is defined as the ratio of tritium specific activity in lyophilized organisms (μCi/gH) to that in water (μCi/gH). The maximum R values were 0.5 in diatoms: Chaetoceros gracilis, 0.2 in bacteria: Escherichia coli, 0.5 in brine shrimps: Artemia salina, and 0.32 in Japanese killifish: Oryzias latipes under the growing condition in which tritium accumulation was due to tritium in tritiated water and not tritiated foods. Brine shrimps and Japanese killifish were grown from larve to adult in tritiated sea water and were fed on tritiated foods (model food chain). Their R values were 0.70 and 0.67, respectively. Bacteria, which grew in tritiated water by adding the hydrolysate of tritiated brine shrimps, showed a maximum R value at 0.32. The R values of each organ of Japanese killifish and of DNA and the nucleotides purified from brine shrimps growing in tritiated water with or without tritiated food were measured to estimate the tritium distribution in the body or various molecules of the organisms. These results did not indicate concentration of tritium in specific organs or compounds. The changes of specific activity of tritium in these organisms were measured when they were transferred to non-tritiated water. These retention of tritium was not only different among the tissues but also depended on whether or not the organisms were reared with tritiated foods. (author)

  9. Tritium decay helium-3 effects in tungsten

    Directory of Open Access Journals (Sweden)

    M. Shimada

    2017-08-01

    Full Text Available Tritium (T implanted by plasmas diffuses into bulk material, especially rapidly at elevated temperatures, and becomes trapped in neutron radiation-induced defects in materials that act as trapping sites for the tritium. The trapped tritium atoms will decay to produce helium-3 (3He atoms at a half-life of 12.3 years. 3He has a large cross section for absorbing thermal neutrons, which after absorbing a neutron produces hydrogen (H and tritium ions with a combined kinetic energy of 0.76 MeV through the 3He(n,HT nuclear reaction. The purpose of this paper is to quantify the 3He produced in tungsten by tritium decay compared to the neutron-induced helium-4 (4He produced in tungsten. This is important given the fact that helium in materials not only creates microstructural damage in the bulk of the material but alters surface morphology of the material effecting plasma-surface interaction process (e.g. material evolution, erosion and tritium behavior of plasma-facing component materials. Effects of tritium decay 3He in tungsten are investigated here with a simple model that predicts quantity of 3He produced in a fusion DEMO FW based on a neutron energy spectrum found in literature. This study reveals that: (1 helium-3 concentration was equilibrated to ∼6% of initial/trapped tritium concentration, (2 tritium concentration remained approximately constant (94% of initial tritium concentration, and (3 displacement damage from 3He(n,HT nuclear reaction became >1 dpa/year in DEMO FW.

  10. Environmental enrichment reduces innate anxiety with no effect on depression-like behaviour in mice lacking the serotonin transporter.

    Science.gov (United States)

    Rogers, Jake; Li, Shanshan; Lanfumey, Laurence; Hannan, Anthony J; Renoir, Thibault

    2017-08-14

    Along with being the main target of many antidepressant medications, the serotonin transporter (5-HTT) is known to be involved in the pathophysiology of depression and anxiety disorders. In line with this, mice with varying 5-HTT genotypes are invaluable tools to study depression- and anxiety-like behaviours as well as the mechanisms mediating potential therapeutics. There is clear evidence that both genetic and environmental factors play a role in the aetiology of psychiatric disorders. In that regard, housing paradigms which seek to enhance cognitive stimulation and physical activity have been shown to exert beneficial effects in animal models of neuropsychiatric disorders. In the present study, we examined the effects of environmental enrichment on affective-like behaviours and sensorimotor gating function of 5-HTT knock-out (KO) mice. Using the elevated-plus maze and the light-dark box, we found that environmental enrichment ameliorated the abnormal innate anxiety of 5-HTT KO mice on both tests. In contrast, environmental enrichment did not rescue the depression-like behaviour displayed by 5-HTT KO mice in the forced-swim test. Finally, measuring pre-pulse inhibition, we found no effect of genotype or treatment on sensorimotor gating. In conclusion, our data suggest that environmental enrichment specifically reduces innate anxiety of 5-HTT KO mice with no amelioration of the depression-like behaviour. This has implications for the current use of clinical interventions for patients with symptoms of both anxiety and depression. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. The cycling of tritium and other radionuclides of global character in different types of ecosystems. Part of a coordinated programme

    International Nuclear Information System (INIS)

    Yuthamanop, A.

    1978-11-01

    A study was carried out to investigate the uptake and release of tritium by the body water and tissue in the fresh water fish under laboratory conditions. Two species of fresh water fishes were used for this experimentation, namely, Helostoma temmincki and Tilapia nilotica. The results obtained were that the uptake of tritium by body water of both fresh water fishes reached equilibrium with the pool specific activity very quickly, i.e. Helostoma temmincki and Tilapia nilotica, both of them showed approximately 4 hours after exposure to HTO to reach equilibrium where as the release of tritium by the body water showed that about 11 hours the activity remained constant after transfer to inactive water. This two species of fresh water fish showed no significant difference in behaviour of uptake and release of tritium by the body water

  12. Modelling diffusion feedbacks between technology performance, cost and consumer behaviour for future energy-transport systems

    Science.gov (United States)

    Tran, Martino; Brand, Christian; Banister, David

    2014-04-01

    Emerging technologies will have important impacts on sustainability objectives. Yet little is known about the explicit feedbacks between consumer behaviour and technological change, and the potential impact on mass market penetration. We use the UK as a case-study to explore the dynamic interactions between technology supply, performance, cost, and heterogeneous consumer behaviour and the resulting influence on long term market diffusion. Simulations of competing vehicle technologies indicate that petrol hybrids (HEVs) dominate the market over the long-term because they benefit from improved performance and are able to reach the steep part of the diffusion curve by 2025 while competing technologies remain in the early stages of growth and are easier to displace in the market. This is due to the cumulative build-up of stock and slow fleet turnover creating inertia in the technological system. Consequently, it will be difficult to displace incumbent technologies because of system inertia, cumulative growth in stock, long operational life, and consumer risk aversion to new unproven technologies. However, when accounting for both technological and behavioural change, simulations indicate that if investment can reach 30-40% per annum growth in supply, combined with steady technology improvements, and more sophisticated agent decision making such as accounting for full technology lifecycle cost and performance, full battery electric vehicles could displace the incumbent system by 2050.

  13. TRITIUM RESERVOIR STRUCTURAL PERFORMANCE PREDICTION

    Energy Technology Data Exchange (ETDEWEB)

    Lam, P.S.; Morgan, M.J

    2005-11-10

    The burst test is used to assess the material performance of tritium reservoirs in the surveillance program in which reservoirs have been in service for extended periods of time. A materials system model and finite element procedure were developed under a Savannah River Site Plant-Directed Research and Development (PDRD) program to predict the structural response under a full range of loading and aged material conditions of the reservoir. The results show that the predicted burst pressure and volume ductility are in good agreement with the actual burst test results for the unexposed units. The material tensile properties used in the calculations were obtained from a curved tensile specimen harvested from a companion reservoir by Electric Discharge Machining (EDM). In the absence of exposed and aged material tensile data, literature data were used for demonstrating the methodology in terms of the helium-3 concentration in the metal and the depth of penetration in the reservoir sidewall. It can be shown that the volume ductility decreases significantly with the presence of tritium and its decay product, helium-3, in the metal, as was observed in the laboratory-controlled burst tests. The model and analytical procedure provides a predictive tool for reservoir structural integrity under aging conditions. It is recommended that benchmark tests and analysis for aged materials be performed. The methodology can be augmented to predict performance for reservoir with flaws.

  14. Analysis of a global database containing tritium in precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, R. L. [Savannah River Site (SRS), Aiken, SC (United States); Rabun, R. L. [Savannah River Site (SRS), Aiken, SC (United States); Heath, M. [Savannah River Site (SRS), Aiken, SC (United States)

    2016-02-17

    The International Atomic Energy Agency (IAEA) directed the collection of tritium in water samples from the mid-1950s to 2009. The Global Network of Isotopes in Precipitation (GNIP) data examined the airborne movement of isotope releases to the environment, with an objective of collecting spatial data on the isotope content of precipitation across the globe. The initial motivation was to monitor atmospheric thermonuclear test fallout through tritium, deuterium, and oxygen isotope concentrations, but after the 1970s the focus changed to being an observation network of stable hydrogen and oxygen isotope data for hydrologic studies. The GNIP database provides a wealth of tritium data collections over a long period of time. The work performed here primarily examined data features in the past 30 years (after much of the effects of above-ground nuclear testing in the late 1950s to early 1960s decayed away), revealing potentially unknown tritium sources. The available data at GNIP were reorganized to allow for evaluation of trends in the data both temporally and spatially. Several interesting cases were revealed, including relatively high measured concentrations in the Atlantic and Indian Oceans, Russia, Norway, as well as an increase in background concentration at a collector in South Korea after 2004. Recent data from stations in the southeastern United States nearest to the Savannah River Site do not indicate any high values. Meteorological impacts have not been considered in this study. Further research to assess the likely source location of interesting cases using transport simulations and/or literature searches is warranted.

  15. Influence of start up and pulsed operation on tritium release and inventory of NET ceramic blanket

    International Nuclear Information System (INIS)

    Iseli, M.; Esser, B.

    1989-01-01

    A first estimate for the tritium release behaviour of a ceramic breeder blanket in pulsed operation is obtained by assuming a linear steady state temperature distribution and taking into account the time constant of the thermal behaviour. The release behaviour of the breeder exposed to consecutive periods of tritium generation is described with an analytical solution of the diffusion equation. The results are compared with a simple exponential approach valid for surfacte desorption controlled release. The exponential model is used to simulate a blanket with aluminate as breeder material, which takes longest to reach steady state. The simulation demonstrates that a significant fraction (>67%) of steady state can be achieved after a testing time of about one day. (author). 7 refs.; 8 figs.; 3 tabs

  16. PDRD (SR13046) TRITIUM PRODUCTION FINAL REPORT

    Energy Technology Data Exchange (ETDEWEB)

    Smith, P.; Sheetz, S.

    2013-09-30

    Utilizing the results of Texas A&M University (TAMU) senior design projects on tritium production in four different small modular reactors (SMR), the Savannah River National Laboratory’s (SRNL) developed an optimization model evaluating tritium production versus uranium utilization under a FY2013 plant directed research development (PDRD) project. The model is a tool that can evaluate varying scenarios and various reactor designs to maximize the production of tritium per unit of unobligated United States (US) origin uranium that is in limited supply. The primary module in the model compares the consumption of uranium for various production reactors against the base case of Watts Bar I running a nominal load of 1,696 tritium producing burnable absorber rods (TPBARs) with an average refueling of 41,000 kg low enriched uranium (LEU) on an 18 month cycle. After inputting an initial year, starting inventory of unobligated uranium and tritium production forecast, the model will compare and contrast the depletion rate of the LEU between the entered alternatives. This is an annual tritium production rate of approximately 0.059 grams of tritium per kilogram of LEU (g-T/kg-LEU). To date, the Nuclear Regulatory Commission (NRC) license has not been amended to accept a full load of TPBARs so the nominal tritium production has not yet been achieved. The alternatives currently loaded into the model include the three light water SMRs evaluated in TAMU senior projects including, mPower, Holtec and NuScale designs. Initial evaluations of tritium production in light water reactor (LWR) based SMRs using optimized loads TPBARs is on the order 0.02-0.06 grams of tritium per kilogram of LEU used. The TAMU students also chose to model tritium production in the GE-Hitachi SPRISM, a pooltype sodium fast reactor (SFR) utilizing a modified TPBAR type target. The team was unable to complete their project so no data is available. In order to include results from a fast reactor, the SRNL

  17. In situ measurements of tritium evapotranspiration (³H-ET) flux over grass and soil using the gradient and eddy covariance experimental methods and the FAO-56 model.

    Science.gov (United States)

    Connan, O; Maro, D; Hébert, D; Solier, L; Caldeira Ideas, P; Laguionie, P; St-Amant, N

    2015-10-01

    The behaviour of tritium in the environment is linked to the water cycle. We compare three methods of calculating the tritium evapotranspiration flux from grassland cover. The gradient and eddy covariance methods, together with a method based on the theoretical Penmann-Monteith model were tested in a study carried out in 2013 in an environment characterised by high levels of tritium activity. The results show that each of the three methods gave similar results. The various constraints applying to each method are discussed. The results show a tritium evapotranspiration flux of around 15 mBq m(-2) s(-1) in this environment. These results will be used to improve the entry parameters for the general models of tritium transfers in the environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Tritium module for ITER/Tiber system code

    International Nuclear Information System (INIS)

    Finn, P.A.; Willms, S.; Busigin, A.; Kalyanam, K.M.

    1988-01-01

    A tritium module was developed for the ITER/Tiber system code to provide information on capital costs, tritium inventory, power requirements and building volumes for these systems. In the tritium module, the main tritium subsystems/emdash/plasma processing, atmospheric cleanup, water cleanup, blanket processing/emdash/are each represented by simple scaleable algorithms. 6 refs., 2 tabs

  19. Optimization of tritium management within the ITER project

    International Nuclear Information System (INIS)

    Cortes, P.; Elbez-Uzan, J.; Glugla, M.; Rosanvallon, S.; Ciattaglia, S.; Iseli, M.; Rodriguez-Rodrigo, L.

    2009-01-01

    The authors describe the tritium cycle existing within the ITER project and which has been considered since its beginning. They indicate how confinement systems ensure tritium confinement, how tritium is recovered and processed. They indicate the different tritium management optimization ways which have been identified and integrated into the ITER design

  20. 10 CFR 39.55 - Tritium neutron generator target sources.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Tritium neutron generator target sources. 39.55 Section 39... Equipment § 39.55 Tritium neutron generator target sources. (a) Use of a tritium neutron generator target....77. (b) Use of a tritium neutron generator target source, containing quantities exceeding 1,110 GBg...

  1. Urban structure and transport behaviour. Results from the survey of transport habits; Bystruktur og transportadfaerd. Hvad siger transportvaneundersoegelsen?

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, L.

    2001-12-01

    The purpose of this report is to analyse the effects on private transport and environmental impact from urban size and structure, and the localisation. In this analysis, the CO{sub 2}-emission is used as the indicator of the environmental impact of the transport i.e. as a result of the energy consumption. The report is organised in 3 main chapters concerning localisation of residential areas, workplace, and centre functions. One of the important results from the analyses is the environmental benefit of avoiding residential development in smaller towns and villages. It is especially important to avoid urban sprawl around the big cities. Concentration in the big cities or in the neighbouring cities is environmentally much more promising. On the other hand it might be expedient to promote a slow development with workplaces in smaller towns to get a good balance between inhabitants and workplaces but it is important to give priority to non-specialised workplaces. Residential or business development in whichever size of the cities above 10,000 inhabitants makes no difference. On the other hand an expansion of centre activities has substantial effect on the CO{sub 2}-emission especially in cities with more than 22,000 inhabitants. Variation in localization inside the cities influences the CO{sub 2}-emission much more than the variability between cities. Residential areas as well as workplace intensive business ought to be promoted at central places near the stations. Upon deciding whether to give priority to residential areas or business at an actual area, more aspects need to be considered. One problem is that a residence and a workplace generate different person kilometres and the areas they occupy vary. It seems to be best to give priority to residential areas in the central areas and to business development around the stations. But this depends on the actual conditions and more detailed analyses might also be revealed. A planning policy promoting a development with

  2. Perspectives for tritium recovery from liquid Pb83Li17 alloy

    International Nuclear Information System (INIS)

    Pierini, G.

    1983-01-01

    A preliminary analysis has been made on the perspectives of tritium recovery from a blanket constituted by liquid Pb 83 Li 17 alloy, by investigating the Tsub(2g) 2T alloy thermodynamic behaviour and trying to individuate those chemico-physical characteristics of which knowledge is useful for the effective design of the apparatus. In the light of the recent work carried out on the systems, hydrogen and its isotopes with molten Li-Pb eutectics, it has been possible to individuate a fair reliability of the Sieverts constant for the T 2 -Pb 83 Li 17 system. As far as the kinetics of the tritium desorption process from the liquid phase are concerned, the hydrogen (and its isotopes) transfer rates across the liquid interphase have been evaluated. Even though in first approximation the diffusion coefficient of tritium in the molten alloy at 400 0 C has been found. Then, the processing equations of attractive tritium recovery systems have been presented, individuating the fundamental parameters and reporting an example of applied engineering of the desorption system in a packed column. None of these tritium recovery systems seem incompatible at the actual state of the research

  3. Management of tritium-contaminated wastes a survey of alternative options

    International Nuclear Information System (INIS)

    Mannone, F.

    1990-01-01

    The European Tritium Handling Experimental Laboratory (ETHEL) under construction on the site of Ispra Joint Research Centre of the Commission of European Communities has been commissioned to experimentally develop operational and environmental safety aspects related to the tritium technology in fusion, i.e. dealing with the behaviour and reliability of materials, equipment and containment systems under tritium impact. For this reason a part of the experimental activities to be performed in ETHEL will be devoted to laboratory research on tritiated waste management. However, since all experimental activities planned for the execution in ETHEL will by itselves generate tritiated wastes, current strategies and practices to be applied for the routine management of these wastes need also to be defined. To attain this target an adequate background information must be provided, which is the intent of this report. Through an exhaustive literature survey tritiated waste management options till now investigated or currently applied in several countries have been assessed. A particular importance has been attached to the tritium leach test programmes, whose results enable to assess the tritium retention efficiency of the various waste immobilization options. The conclusions resulting from the overall assessment are presented

  4. Tritium distributing in stainless steel determined by chemical etchin

    International Nuclear Information System (INIS)

    Xiong Yifu; Luo Deli; Chen Changan; Chen Shicun; Jing Wenyong

    2009-01-01

    The depth distribution of tritium in stainless steel was measured by chemical etching. The results show that the method can more quantitatively evaluate the tritium distributing in stainless steel. The maximum amount of tritium which distributed in crystal lattice of stainless steel is limitted by its solubility at room temperature. The other form of tritium in stainless steel is gaseous tritium that are trapped by defects, impurities, fractures, etc. within it. The gaseous tritium is several times more than the solid-dissolved tritium. (authors)

  5. Tritium monitor with improved gamma-ray discrimination

    Science.gov (United States)

    Cox, Samson A.; Bennett, Edgar F.; Yule, Thomas J.

    1985-01-01

    Apparatus and method for selective measurement of tritium oxide in an environment which may include other radioactive components and gamma radiation, the measurement including the selective separation of tritium oxide from a sample gas through a membrane into a counting gas, the generation of electrical pulses individually representative by rise times of tritium oxide and other radioactivity in the counting gas, separation of the pulses by rise times, and counting of those pulses representative of tritium oxide. The invention further includes the separate measurement of any tritium in the sample gas by oxidizing the tritium to tritium oxide and carrying out a second separation and analysis procedure as described above.

  6. Tritium Decay Helium-3 Effects in Tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Shimada, M. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Merrill, B. J. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-06-01

    A critical challenge for long-term operation of ITER and beyond to a Demonstration reactor (DEMO) and future fusion reactor will be the development of plasma-facing components (PFCs) that demonstrate erosion resistance to steady-state/transient heat fluxes and intense neutral/ion particle fluxes under the extreme fusion nuclear environment, while at the same time minimizing in-vessel tritium inventories and permeation fluxes into the PFC’s coolant. Tritium will diffuse in bulk tungsten at elevated temperatures, and can be trapped in radiation-induced trap site (up to 1 at. % T/W) in tungsten [1,2]. Tritium decay into helium-3 may also play a major role in microstructural evolution (e.g. helium embrittlement) in tungsten due to relatively low helium-4 production (e.g. He/dpa ratio of 0.4-0.7 appm [3]) in tungsten. Tritium-decay helium-3 effect on tungsten is hardly understood, and its database is very limited. Two tungsten samples (99.99 at. % purity from A.L.M.T. Co., Japan) were exposed to high flux (ion flux of 1.0x1022 m-2s-1 and ion fluence of 1.0x1026 m-2) 0.5%T2/D2 plasma at two different temperatures (200, and 500°C) in Tritium Plasma Experiment (TPE) at Idaho National Laboratory. Tritium implanted samples were stored at ambient temperature in air for more than 3 years to investigate tritium decay helium-3 effect in tungsten. The tritium distributions on plasma-exposed was monitored by a tritium imaging plate technique during storage period [4]. Thermal desorption spectroscopy was performed with a ramp rate of 10°C/min up to 900°C to outgas residual deuterium and tritium but keep helium-3 in tungsten. These helium-3 implanted samples were exposed to deuterium plasma in TPE to investigate helium-3 effect on deuterium behavior in tungsten. The results show that tritium surface concentration in 200°C sample decreased to 30 %, but tritium surface concentration in 500°C sample did not alter over the 3 years storage period, indicating possible tritium

  7. Tritium Room Air Monitor Operating Experience Review

    Energy Technology Data Exchange (ETDEWEB)

    L. C. Cadwallader; B. J. Denny

    2008-09-01

    Monitoring the breathing air in tritium facility rooms for airborne tritium is a radiological safety requirement and a best practice for personnel safety. Besides audible alarms for room evacuation, these monitors often send signals for process shutdown, ventilation isolation, and cleanup system actuation to mitigate releases and prevent tritium spread to the environment. Therefore, these monitors are important not only to personnel safety but also to public safety and environmental protection. This paper presents an operating experience review of tritium monitor performance on demand during small (1 mCi to 1 Ci) operational releases, and intentional airborne inroom tritium release tests. The tritium tests provide monitor operation data to allow calculation of a statistical estimate for the reliability of monitors annunciating in actual tritium gas airborne release situations. The data show a failure to operate rate of 3.5E-06/monitor-hr with an upper bound of 4.7E-06, a failure to alarm on demand rate of 1.4E-02/demand with an upper bound of 4.4E-02, and a spurious alarm rate of 0.1 to 0.2/monitor-yr.

  8. Thermal release of tritium from SS316

    International Nuclear Information System (INIS)

    Torikai, Y.; Naoe, S.; Penzhorn, R.D.; Akaishi, K.; Watanabe, K.; Matsuyama, M.

    2007-01-01

    In an effort to improve current understanding of the mechanisms controlling the long-term release of tritium incorporated thermally into stainless steel SS316 and to develop reliable as well as economically feasible techniques for the conditioning of tritium-containing metallic wastes, a systematic investigation is underway in Toyama under carefully controlled conditions. The release rate of tritium from SS316 at ambient pressure was determined experimentally in a flow system at several constant temperatures within the range 287-573 K for rather extended periods of time. Under these conditions HTO was found to constitute by far the most important tritium-containing species being released, i.e. approx. 99 %. Much data has accumulated in recent years with a variety of specimens, i.e. type of stainless steel and specimen dimension, loaded with tritium under different pressure and temperature conditions. Dynamic behavior of long-term tritium release has been successfully modeled using a onedimensional diffusion equation and assuming that the release rate is governed by the tritium flux at the metal surface boundary. The implications of the results for interim storage and thermal conditioning of stainless steel waste will be discussed. (orig.)

  9. Cernavoda NPP - Management of internal tritium exposures

    International Nuclear Information System (INIS)

    Chitu, Catalina; Popescu, Ion; Samson, Liliana; Simionov, Vasile

    2010-01-01

    Full text: During normal operation of a CANDU nuclear power plant significant tritium quantities are generated. Through design solutions that have been implemented we manage to control the tritium losses from the reactor systems and keep them as low as possible. Special dryers are designed and are used to remove moisture from different ventilation systems of a CANDU reactor in order to maintain tritium in air concentration and gaseous tritium emissions below the limits established by the national authorities. Vapor Recovery System is designed to control tritium in air concentration and to recover heavy water loss from PHT and Moderator Systems and to control the air circulation, providing atmosphere separation between different areas of the Reactor Building. Cernavoda NPP developed a special strategy in order to control workers' internal exposures to tritium and dedicated programs are running to implement this strategy: improvement of radiation protection procedures; increasing equipment performances; leakages prevention through maintenance program; finalization of the de-tritiation facility. This paper presents the evolution of workers tritium exposure and emphasizes the results of the ALARA policy promoted by Cernavoda NPP management. (authors)

  10. Risks of tritium and their mitigation

    International Nuclear Information System (INIS)

    Ichimasa, Y.; Shiba, H.; Ichimasa, M.; Chikuuti, M.; Akita, Y.

    1992-01-01

    In this study, the effects of an antibacterial drug, norfloxacin, and an antibiotic, clindamycin, on in vivo oxidation of tritium gas in rats were investigated. Wistar strain male rats were used. They were provided with a standard diet, water ad libitum, and maintained in glass metabolic cages of approximately 20 liters capacity. The air flow and temperature were controlled. To investigate the availability of norfloxacin and clindamycin on the inhibition effects of the oxidation of tritium gas, two types of the experiments were conducted one was that, before the exposure to tritium gas for 2 hours, norfloxacin or clindamycin was administrated to rats three times a day for 4 days, and the other was administration of a drug after tritium gas exposure. After the exposure to tritium gas, blood, the liver, urine and feces samples were collected from rats and the radioactivity of them was determined after combustion using a sample oxidizer. In the case of norfloxacin, tritium concentration in rat body decreased one fifth of that in non-treated rats. On the other hand, administration of clindamycin shortened the biological half-life of tritium in urine to three fifth of that of non-treated rats. (author)

  11. Quick management of accidental tritium exposure cases.

    Science.gov (United States)

    Singh, Vishwanath P; Badiger, N M; Managanvi, S S; Bhat, H R

    2012-07-01

    Removal half-life (RHL) of tritium is one of the best means for optimising medical treatment, reduction of committed effective dose (CED) and quick/easy handling of a large group of workers for medical treatment reference. The removal of tritium from the body depends on age, temperature, relative humidity and daily rainfall; so tritium removal rate, its follow-up and proper data analysis and recording are the best techniques for management of accidental acute tritium exposed cases. The decision of referring for medical treatment or medical intervention (MI) would be based on workers' tritium RHL history taken from their bodies at the facilities. The workers with tritium intake up to 1 ALI shall not be considered for medical treatment as it is a derived limit of annual total effective dose. The short-term MI may be considered for tritium intake of 1-10 ALI; however, if the results show intake ≥100 ALI, extended strong medical/therapeutic intervention may be recommended based on the severity of exposure for maximum CED reduction requirements and annual total effective dose limit. The methodology is very useful for pressurized heavy water reactors (PHWRs) which are mainly operated by Canada and India and future fusion reactor technologies. Proper management will optimise the cases for medical treatment and enhance public acceptance of nuclear fission and fusion reactor technologies.

  12. Isotopic fractionation of tritium in biological systems.

    Science.gov (United States)

    Le Goff, Pierre; Fromm, Michel; Vichot, Laurent; Badot, Pierre-Marie; Guétat, Philippe

    2014-04-01

    Isotopic fractionation of tritium is a highly relevant issue in radiation protection and requires certain radioecological considerations. Sound evaluation of this factor is indeed necessary to determine whether environmental compartments are enriched/depleted in tritium or if tritium is, on the contrary, isotopically well-distributed in a given system. The ubiquity of tritium and the standard analytical methods used to assay it may induce biases in both the measurement and the signification that is accorded to the so-called fractionation: based on an exhaustive review of the literature, we show how, sometimes large deviations may appear. It is shown that when comparing the non-exchangeable fraction of organically bound tritium (neOBT) to another fraction of tritium (e.g. tritiated water) the preparation of samples and the measurement of neOBT reported frequently led to underestimation of the ratio of tritium to hydrogen (T/H) in the non-exchangeable compartment by a factor of 5% to 50%. In the present study, corrections are proposed for most of the biological matrices studied so far. Nevertheless, the values of isotopic fractionation reported in the literature remain difficult to compare with each other, especially since the physical quantities and units often vary between authors. Some improvements are proposed to better define what should encompass the concepts of exchangeable and non-exchangeable fractions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Quick management of accidental tritium exposure cases

    International Nuclear Information System (INIS)

    Singh, V. P.; Badiger, N. M.; Managanvi, S. S.; Bhat, H. R.

    2008-01-01

    Removal half-life (RHL) of tritium is one of the best means for optimising medical treatment, reduction of committed effective dose (CED) and quick/easy handling of a large group of workers for medical treatment reference. The removal of tritium from the body depends on age, temperature, relative humidity and daily rainfall; so tritium removal rate, its follow-up and proper data analysis and recording are the best techniques for management of accidental acute tritium exposed cases. The decision of referring for medical treatment or medical intervention (MI) would be based on workers' tritium RHL history taken from their bodies at the facilities. The workers with tritium intake up to 1 ALI shall not be considered for medical treatment as it is a derived limit of annual total effective dose. The short-term MI may be considered for tritium intake of 1-10 ALI; however, if the results show intake ≥100 ALI, extended strong medical/therapeutic intervention may be recommended based on the severity of exposure for maximum CED reduction requirements and annual total effective dose limit. The methodology is very useful for pressurized heavy water reactors (PHWRs) which are mainly operated by Canada and India and future fusion reactor technologies. Proper management will optimise the cases for medical treatment and enhance public acceptance of nuclear fission and fusion reactor technologies. (authors)

  14. Conceptual design of tritium accountancy system for LLCB TBM

    International Nuclear Information System (INIS)

    Patel, Rudreksh; Sircar, Amit

    2017-01-01

    Lead Lithium Ceramic Breeder (LLCB) Test Blanket Module (TBM) will be tested in ITER for performance evaluation of high grade of heat extraction and tritium breeding. The bred tritium in the breeder materials is extracted and recovered by Tritium Extraction System (TES), whereas tritium permeated from breeder materials to helium coolants, viz., primary coolant and secondary coolant, is recovered by Coolant Purification System (CPS). This recovered tritium has to be accounted before transferring it to tritium plant (i.e., ITER inner fuel). This tritium accountancy is performed by Tritium Accountancy System (TAS). In addition to tritium accountancy, TAS also provides necessary data for the validation of design and modelling tools.In this work, we have presented conceptual design of TAS. It also describes operational philosophy, process parameters, process flow diagram, and interface details with ITER tritium plant. (author)

  15. Tritium system design studies of fusion experimental breeder

    International Nuclear Information System (INIS)

    Deng Baiquan; Huang Jinhua

    2003-01-01

    A summary of the tritium system design studies for the engineering outline design of a fusion experimental breeder (FEB-E) is presented. This paper is divided into three sections. In first section, the geometry, loading features and tritium concentrations in liquid lithium of tritium breeding zones of blanket are described. The tritium flow chart corresponding to the tritium fuel cycle system has been constructed, and the inventories in ten subsystems are calculated using SWITRIM code in section 2. Results show that the necessary initial tritium storage to start up FEB-E with fusion power of 143 MW is about 319 g. In final section, the tritium leakage issues under different operation circumstances have been analyzed. It was found that the potential danger of tritium leakage could be resulted from the exhausted gas of the diverter system. It is important to elevate the tritium burnup fraction and reduce the tritium throughput. (authors)

  16. Tritium extraction technologies and DEMO requirements

    Energy Technology Data Exchange (ETDEWEB)

    Demange, D., E-mail: david.demange@kit.edu [Karlsruhe Institute of Technology, Institute for Technical Physics, Tritium Laboratory Karlsruhe, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Antunes, R.; Borisevich, O.; Frances, L. [Karlsruhe Institute of Technology, Institute for Technical Physics, Tritium Laboratory Karlsruhe, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Rapisarda, D. [Laboratorio Nacional de Fusión, EURATOM-CIEMAT, 28040 Madrid (Spain); Santucci, A. [ENEA for EUROfusion, Via E. Fermi 45, 00044 Frascati, Roma (Italy); Utili, M. [ENEA CR Brasimone, 40032 Camugnano, BO (Italy)

    2016-11-01

    Highlights: • We detail the R&D plan for tritium technology of the European DEMO breeding blanket. • We study advanced and efficient extraction techniques to improve tritium management. • We consider inorganic membranes and catalytic membrane reactor for solid blankets. • We consider permeator against vacuum and vacuum sieve tray for liquid blankets. - Abstract: The conceptual design of the tritium extraction system (TES) for the European DEMO reactor is worked out in parallel for four different breeding blankets (BB) retained by EUROfusion. The TES design has to be tackled in an integrated manner optimizing the synergy with the directly interfacing inner fuel cycle, while minimizing the tritium permeation into the coolant. Considering DEMO requirements, it is most likely that only advanced technologies will be suitable for the tritium extraction systems of the BB. This paper overviews the European work programme for R&D on tritium technology for the DEMO BB, summaries the general first outcomes, and details the specific and comprehensive R&D program to study experimentally immature but promising technologies such as vacuum sieve tray or permeator against vacuum for tritium extraction from PbLi, and advanced inorganic membranes and catalytic membrane reactor for tritium extraction from He. These techniques are simple, fully continuous, likely compact with contained energy consumption. Several European Laboratories are joining their efforts to deploy several new experimental setups to accommodate the tests campaigns that will cover small scale experiments with tritium and inactive medium scale tests so as to improve the technology readiness level of these advanced processes.

  17. Optimization of tritium management within the ITER project; Optimisation de la gestion du tritium dans le projet ITER

    Energy Technology Data Exchange (ETDEWEB)

    Cortes, P.; Elbez-Uzan, J.; Glugla, M.; Rosanvallon, S.; Ciattaglia, S.; Iseli, M.; Rodriguez-Rodrigo, L. [ITER Organization, CS 9 0046, 13067 St Paul lez Durance Cedex (France)

    2009-07-01

    The authors describe the tritium cycle existing within the ITER project and which has been considered since its beginning. They indicate how confinement systems ensure tritium confinement, how tritium is recovered and processed. They indicate the different tritium management optimization ways which have been identified and integrated into the ITER design

  18. Serotonin transporter deficiency in rats improves inhibitory control but not behavioural flexibility

    NARCIS (Netherlands)

    Homberg, Judith R.; Pattij, Tommy; Janssen, Mieke C. W.; Ronken, Eric; De Boer, Sietse F.; Schoffelmeer, Anton N. M.; Cuppen, Edwin

    2007-01-01

    Impulsivity and aggression have been suggested to inversely correlate with central serotonin (5-HT) levels in a trait-like manner. However, this relationship is far from straightforward. In the present study we addressed the effect of lifelong reduced or absent serotonin transporter (SERT) function,

  19. Serotonin transporter deficiency in rats improves inhibitory control but not behavioural flexibility.

    NARCIS (Netherlands)

    Homberg, J.R.; Pattij, T.; Janssen, M.C.; Ronken, E.; Boer, S.F. de; Schoffelmeer, A.N.; Cuppen, E.

    2007-01-01

    Impulsivity and aggression have been suggested to inversely correlate with central serotonin (5-HT) levels in a trait-like manner. However, this relationship is far from straightforward. In the present study we addressed the effect of lifelong reduced or absent serotonin transporter (SERT) function,

  20. Tritium labeling of amino acids and peptides with liquid and solid tritium

    International Nuclear Information System (INIS)

    Souers, P.C.; Coronado, P.R.; Peng, C.T.; Hua, R.L.

    1988-01-01

    Amino acids and peptides were labeled with liquid and solid tritium at 21/degree/K and 9/degree/K. At these low temperatures radiation degradation is minimal, and tritium incorporation increases with tritium concentration and exposure time. Ring saturation in L-phenylalanine does not occur. Peptide linkage in oligopeptides is stable toward tritium. Deiodination in 3-iodotyrosine and 3,5-diiodotyrosine occurs readily and proceeds in steps by losing one iodine atom at a time. Nickel and noble metal supported catalysts when used as supports for dispersion of the substrate promote tritium labeling at 21 K. Our study shows that both liquid and solid tritiums are potentially useful agents for labeling peptides and proteins

  1. Conversion of tritium gas to tritiated water

    International Nuclear Information System (INIS)

    Papagiannakopoulos, P.J.; Easterly, C.E.

    1979-05-01

    The mechanisms of conversion of tritium gas to tritiated water (HTO) have been examined for several tritium gaseous mixtures. The physical and chemical processes involved in the self-radiolysis of such mixtures have been analyzed and the kinetics involved in the formation of HTO has been presented. It has been determined that the formation of the H and/or OH free radicals, as intermediate species, are of significance in the formation of HTO. Therefore, the problem of reducing the rate of formation of tritiated water in a mixture of gaseous tritium with atmospheric components is one of finding an effective scavenger for the H and/or OH free radicals

  2. Preparation of honey sample for tritium monitoring

    International Nuclear Information System (INIS)

    Chen Bingru; Wang Chenlian; Wang Weihua

    1989-01-01

    The method of preparation of honey sample for tritium monitoring was described. The equipments consist of an air and honey supply system, a quartz combustor with CM-type monolithic combustion catalyst and a condensation system. In the equipments, honey sample was converted into cooling water by the distilling, cracking and carbonizing procedures for tritium counting. The recovery ratio is 99.0 ± 4.5 percent for tritiated water and 96.0 ± 2.0 for tritiated organic compounds. It is a feasible preparing method for the total tritium monitoring in honey sample

  3. Electrolytic gettering of tritium from air

    International Nuclear Information System (INIS)

    Souers, P.C.; Tsugawa, R.T.; Stevens, C.G.

    1983-01-01

    We have removed 90% of 1 part-per-million tritium gas in air of 25% to 35% humidity by the dc electrical action of the solid proton electrolyte hydrogen uranyl phosphate (HUP). Gettering takes 5 to 24 hours for a 1 cm 2 HUP disc at 2 to 4 V in a static, 1200 cc gas volume. Hydrogen gas may be used to flush captured tritium through the HUP. Liquid water leaches out the tritium but water vapor is ineffective. This technique promises an alternative to the conventional catalyst/zeolite method

  4. Serotonin 2A receptor, serotonin transporter and dopamine transporter alterations in dogs with compulsive behaviour as a promising model for human obsessive-compulsive disorder.

    Science.gov (United States)

    Vermeire, Simon; Audenaert, Kurt; De Meester, Rudy; Vandermeulen, Eva; Waelbers, Tim; De Spiegeleer, Bart; Eersels, Jos; Dobbeleir, André; Peremans, Kathelijne

    2012-01-30

    Neuro-imaging studies have shown altered, yet often inconsistent, serotonergic and dopaminergic neurotransmission in patients with obsessive-compulsive disorder (OCD). We investigated both serotonergic and dopaminergic neurotransmission in 9 drug-naïve dogs with compulsive behaviour, as a potential model for human OCD. Single photon emission computed tomography was used with (123)I-R91150 and (123)I-FP-CIT, in combination with (99m)Tc-ECD brain perfusion co-registration, to measure the serotonin (5-HT) 2A receptor, dopamine transporter (DAT) and serotonin transporter (SERT) availability. Fifteen normally behaving dogs were used as reference group. Significantly lower 5-HT2A receptor radioligand availability in frontal and temporal cortices (bilateral) was observed. Further, in 78% of the compulsive dogs abnormal DAT ratios in left and right striatum were demonstrated. Interestingly, both increased and decreased DAT ratios were observed. Finally, significantly lower subcortical perfusion and (hypo)thalamic SERT availability were observed in the compulsive dogs. This study provides evidence for imbalanced serotonergic and dopaminergic pathways in the pathophysiology of compulsions in dogs. The similarities with the altered neurotransmission in human OCD provide construct validity for this non-induced, natural canine model, suggesting its usefulness for future investigations of the pathophysiology of human OCD as well as the effectiveness of psychopharmacological interventions. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  5. Emergent Behaviour

    NARCIS (Netherlands)

    Blom, H.A.P.; Everdij, M.H.C.; Bouarfa, S.; Cook, A; Rivas, D

    2016-01-01

    In complexity science a property or behaviour of a system is called emergent if it is not a property or behaviour of the constituting elements of the system, though results from the interactions between its constituting elements. In the socio-technical air transportation system these interactions

  6. Tritium containing polymers having a polymer backbone substantially void of tritium

    Science.gov (United States)

    Jensen, G.A.; Nelson, D.A.; Molton, P.M.

    1992-03-31

    A radioluminescent light source comprises a solid mixture of a phosphorescent substance and a tritiated polymer. The solid mixture forms a solid mass having length, width, and thickness dimensions, and is capable of self-support. In one aspect of the invention, the phosphorescent substance comprises solid phosphor particles supported or surrounded within a solid matrix by a tritium containing polymer. The tritium containing polymer comprises a polymer backbone which is essentially void of tritium. 2 figs.

  7. Tritium migration at the Gasbuggy site: Evaluation of possible hydrologic pathways

    International Nuclear Information System (INIS)

    Chapman, J.; Mihevc, T.; Lyles, B.

    1996-09-01

    An underground nuclear test named Gasbuggy was conducted in northwestern New Mexico in 1967. Subsequent groundwater monitoring in an overlying aquifer by the U.S. Environmental Protection Agency revealed increasing levels of tritium in monitoring well EPNG 10-36, located 132 m from the test, suggesting migration of contaminants from the nuclear cavity. There are three basic scenarios that could explain the occurrence of tritium in well 10-36: (1) introduction of tritium into the well from the land surface, (2) migration of tritium through the Ojo Alamo Formation, and (3) migration through the Pictured Cliffs Formation. The two subsurface transport scenarios were evaluated with a travel time analysis. In one, transport occurs to the Ojo Alamo sandstone either up the emplacement hole or through fractures created by the blast, and then laterally through the aquifer to the monitoring well. In the other, lateral transport occurs through fractures in the underlying Pictured Cliffs detonation horizon and then migrates up the monitoring well through plugged casing connecting the two formations. The travel time analysis indicates that the hydraulic conductivity measured in the Ojo Alamo Formation is too low for lateral transport to account for the observed arrival of tritium at the monitoring well. This suggests transport either through fractures intersecting the Ojo Alamo close to well EPNG 10-36, or through fractures in the Pictured Cliffs and up through the bottom plug in the well. The transport scenarios were investigated using hydrologic logging techniques and sampling at the monitoring well, with the fieldwork conducted after the removal of a string of 0.05-m-diameter tubing that had previously provided the only monitoring access

  8. Assessing the Tangent Linear Behaviour of Common Tracer Transport Schemes and Their Use in a Linearised Atmospheric General Circulation Model

    Science.gov (United States)

    Holdaway, Daniel; Kent, James

    2015-01-01

    The linearity of a selection of common advection schemes is tested and examined with a view to their use in the tangent linear and adjoint versions of an atmospheric general circulation model. The schemes are tested within a simple offline one-dimensional periodic domain as well as using a simplified and complete configuration of the linearised version of NASA's Goddard Earth Observing System version 5 (GEOS-5). All schemes which prevent the development of negative values and preserve the shape of the solution are confirmed to have nonlinear behaviour. The piecewise parabolic method (PPM) with certain flux limiters, including that used by default in GEOS-5, is found to support linear growth near the shocks. This property can cause the rapid development of unrealistically large perturbations within the tangent linear and adjoint models. It is shown that these schemes with flux limiters should not be used within the linearised version of a transport scheme. The results from tests using GEOS-5 show that the current default scheme (a version of PPM) is not suitable for the tangent linear and adjoint model, and that using a linear third-order scheme for the linearised model produces better behaviour. Using the third-order scheme for the linearised model improves the correlations between the linear and non-linear perturbation trajectories for cloud liquid water and cloud liquid ice in GEOS-5.

  9. Tritium metabolism in cow's milk after administration of tritiated water and of organically bound tritium

    International Nuclear Information System (INIS)

    Hoek, J. van den

    1982-01-01

    Tritium was administered as THO and as organically bound tritium (OBT) to lactating cows. Urine and milk samples were collected and analyzed for tritium content. Plateau levels in milk water and in milk fat, lactose and casein were reached in about 20 days after feeding either THO or OBT. Comparison of the specific activity (pCi 3 H/g H) of the various milk constituents with the specific activity of the body water showed that, after administration of THO, the highest tritium incorporation occurred in lactose (0.58), followed by milk fat (0.36) and casein (0.27). Tritium incorporation in milk dry matter (0.45) is considerably higher than in most tissue components of several mammalian species after continuous ingestion of THO as reported in the literature. After feeding OBT, the highest tritium incorporation occurred in milk fat and to a lesser extent in casein. Tritium levels in lactose were surprisingly low and the reason for this is not clear. They were similar to those in milk water. Tritium levels in milk and urine water showed systematic differences during administration of OBT and after this was stopped. There was more tritium in milk water until the last day of OBT feeding and this situation was reversed after this. (author)

  10. Overview of tritium processing development at the tritium systems test assembly

    International Nuclear Information System (INIS)

    Anderson, J.L.

    1986-01-01

    The Tritium Systems Test Assembly (TSTA) at the Los Alamos National Laboratory has been operating with tritium since June 1984. Presently there are some 50 g of tritium in the main processing loop. This 50 g has been sufficient to do a number of experiments involving the cryogenic distillation isotope separation system and to integrate the fuel cleanup system into the main fuel processing loop. In January 1986 two major experiments were conducted. During these experiments the fuel cleanup system was integrated, through the transfer pumping system, with the isotope separation system, thus permitting testing on the integrated fuel processing loop. This integration of these systems leaves only the main vacuum system to be integrated into the TSTA fuel processing loop. In September 1986 another major tritium experiment was performed in which the integrated loop was operated, the tritium inventory increased to 50 g and additional measurements on the performance of the distillation system were taken. In the period June 1984 through September 1986 the TSTA system has processed well over 10 8 Ci of tritium. Total tritium emissions to the environment over this period have been less than 15 Ci. Personnel exposures during this period have totaled less than 100 person-mRem. To date, the development of tritium technology at TSTA has proceeded in progressive and orderly steps. In two years of operation with tritium, no major design flows have been uncovered

  11. Microbial behaviour and cross contamination between cargoes in containerized transportation of food

    DEFF Research Database (Denmark)

    Abban, Stephen

    . Firstly, the attachment and detachment of bacteria pathogens on container lining materials and apple (food) surfaces were investigated in the absence and presence of food residue. The number of attached cells for the two organisms studied, Escherichia coli and Salmonella Typhimurium, was negatively......Transportation is central to the global food and feed supply chain. Thus issues of safety, especially cross contamination with pathogens during food transit should be important in food handling operations. A large proportion of the worlds’ food cargo is moved using intermodal cargo containers...... chain, its role in food safety cannot be ignored. Unfortunately not much effort has been put, scientifically, into understanding the role of the various features of the transportation links in food cross contamination (compared to studies for homes, processing factories and farm yards). The PhD project...

  12. Contrasts in active transport behaviour across four countries: how do they translate into public health benefits?

    Science.gov (United States)

    Götschi, Thomas; Tainio, Marko; Maizlish, Neil; Schwanen, Tim; Goodman, Anna; Woodcock, James

    2015-05-01

    Countries and regions vary substantially in transport related physical activity that people gain from walking and cycling and in how this varies by age and gender. This study aims to quantify the population health impacts of differences between four settings. The Integrated Transport and Health Model (ITHIM) was used to estimate health impacts from changes to physical activity that would arise if adults in urban areas in England and Wales adopted travel patterns of Switzerland, the Netherlands, and California. The model was parameterised with data from travel surveys from each setting and estimated using Monte Carlo simulation. Two types of scenarios were created, one in which the total travel time budget was assumed to be fixed and one where total travel times varied. Substantial population health benefits would accrue if people in England and Wales gained as much transport related physical activity as people in Switzerland or the Netherlands, whilst smaller but still considerable harms would occur if active travel fell to the level seen in California. The benefits from achieving the travel patterns of the high cycling Netherlands or high walking Switzerland were similar. Differences between high income countries in how people travel have important implications for population health. Copyright © 2015. Published by Elsevier Inc.

  13. Methods of tritium recovery from molten lithium

    International Nuclear Information System (INIS)

    Farookhi, R.; Rogers, J.E.

    1968-01-01

    It is important to keep the tritium inventory in a blanket of a thermonuclear reactor at a low level both to eliminate possible hydriding of structural components and to reduce inventory cost. Removing the tritium from a lithium blanket by fractional distillation, flash vaporization, and fractional crystallization was investigated. No definitive data are available either on the vapor-liquid equilibrium between lithium and tritium at low T 2 concentrations, or on the rate of formation and decomposition of lithium tritide. The final distinction between the recovery systems discussed in this report will depend on such data, but presently distillation appears to be the best alternate to the diffusion scheme proposed by A.P. Fraas. The capital cost of equipment necessary to remove tritium by distillation appears to be greater than 10 million dollars for a 5000 MW system, whereas the capital cost associated with the diffusion process has been estimated to be 4 million dollars

  14. Technologies for immobilization and disposal of tritium

    International Nuclear Information System (INIS)

    Coppari, N.R.

    1996-01-01

    This study was done within a program one of whose objectives was to know the state of the technology development for tritium separation in the moderator circuit at HWR and to define the possible technologies to be applied to the Argentine nuclear power plants. Within this framework the strategies adopted by each country and the available technologies for a safe disposal of tritium, not only in its gaseous state tritium but also as tritiated water were analyzed. It is considered that if the selected separation method is such that the tritium is in its gaseous state, the hydride formation for long periods of immobilization should be studied. whereas if it were triated water immobilization should be studied to choose the technology between cementation and drying agents, in both cases the final disposal site will have to be selected. (author). 8 refs

  15. Survey of pumps for tritium gas

    International Nuclear Information System (INIS)

    Dowell, T.M.

    1983-05-01

    This report considers many different types of pumps for their possible use in pumping tritium gas in the low, intermediate and high vacuum ranges. No one type of pump is suitable for use over the wide range of pumping pressure required in a typical pumping system. The favoured components for such a system are: bellows pump (low vacuum); orbiting scroll pump (intermediate vacuum); magnetically suspended turbomolecular pump (high vacuum); cryopump (high vacuum). Other pumps which should be considered for possible future development are: mound modified vane pump; SRTI wobble pump; roots pump with canned motor. It is proposed that a study be made of a future tritium pumping system in a Canadian tritium facility, e.g. a tritium laboratory

  16. Tritium proof-of-principle injector experiment

    International Nuclear Information System (INIS)

    Fisher, P.W.; Milora, S.L.; Combs, S.K.; Carlson, R.V.; Coffin, D.O.

    1988-01-01

    The Tritium Proof-of-Principle (TPOP) pellet injector was designed and built by Oak Ridge National Laboratory (ORNL) to evaluate the production and acceleration of tritium pellets for fueling future fision reactors. The injector uses the pipe-gun concept to form pellets directly in a short liquid-helium-cooled section of the barrel. Pellets are accelerated by using high-pressure hydrogen supplied from a fast solenoid valve. A versatile, tritium-compatible gas-handling system provides all of the functions needed to operate the gun, including feed gas pressure control and flow control, plus helium separation and preparation of mixtures. These systems are contained in a glovebox for secondary containment of tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory (LANL). 18 refs., 3 figs

  17. Tritium Measurements in Slovenia - Chronology Till 2004

    International Nuclear Information System (INIS)

    Logar, Jasmina Kozar; Vaupotic, Janja; Kobal, Ivan

    2005-01-01

    Almost all the analyses of tritium in Slovenia have been performed by the tritium laboratory at the Jozef Stefan Institute. Nearly 90 % of its measurements have been covered by two national programs, both approved by the Slovenian Nuclear Safety Administration: the radioactive monitoring program in the environs of Krsko Nuclear Power Plant (KNPP) and the program of global radioactive contamination monitoring in the environment. These programs include samples of groundwaters, surface waters, precipitation and drinking waters, as well as liquid and gaseous effluents from KNPP. Tritium was determined in some research projects and in hydrological studies of thermal waters, groundwater and coalmine waters. Tritium in the Karst region was mapped as well as the springs of entire territory of Slovenia. Around 5500 samples have been analyzed up to 2004

  18. Tritium handling facility at KMS Fusion Inc

    International Nuclear Information System (INIS)

    Bowman, C.C.; Vis, V.A.

    1990-01-01

    The tritium facility at KMS Fusion, Inc. supports the inertial confinement fusion research program. The main function of the facility is to fill glass and polymer Microshell (TM) capsules (small fuel containers) to a maximum pressure of 100 atm with tritium (T 2 ) or deuterium--tritium (DT). The recent upgrade of the facility allows us to fill Microshell capsules to a maximum pressure of 200 atm. A second fill port allows us to run long term fills of Macroshell (TM) capsules (large fuel containers) concurrently. The principle processes of the system are: (1) storage of the tritium as a uranium hydride; (2) pressure intensification using cryogenics; and (3) filling of the shells by permeation at elevated temperatures. The design of the facility was centered around a NRC license limit of 6000 Ci

  19. Tritium Inventory in ARIES-AT

    International Nuclear Information System (INIS)

    Longhurst, Glen R.

    2001-01-01

    This report documents an investigation into the tritium inventory expected in the ARIES-AT fusion reactor. ARIES-AT features silicon carbide fibers in a silicon carbide matrix as its primary construction. It uses the same fusion power core as the previous ARIES-RS. Based on experimental results of several researchers, consideration was given to swelling, sputtering, film coatings, erosion, and implantation. Estimates were made of tritium inventory using the TMAP4 code. About 700 g of tritium may be expected in the machine, two thirds of which would reside in the first wall. Under assumed accident conditions that involve first wall temperatures up to 1000 C, evolution of retained tritium may be expected to vary from 0.8 to nearly 40 percent depending on the temperature of the first wall

  20. Investigation of tritium in the aquatic environment

    International Nuclear Information System (INIS)

    Cohen, L.K.

    1977-01-01

    The behavior, cycling and distribution of tritium in an aquatic ecosystem was studied in the field and in the laboratory from 1969 through 1971. Field studies were conducted in the Hudson River Estuary, encompassing a 30 mile region centered about the Indian Point Nuclear Plant. Samples of water, bottom sediment, rooted emergent aquatic plants, fish, and precipitation were collected over a year and a half period from more than 15 locations. Specialized equipment and systems were built to combust and freeze-dry aquatic media to remove and recover the loose water and convert the bound tritium into an aqueous form. An electrolysis system was set up to enrich the tritium concentrations in the aqueous samples to improve the analytical sensitivity. Liquid scintillation techniques were refined to measure the tritium activity in the samples. Over 300 samples were analyzed during the course of the study

  1. Calibrations of a tritium extraction facility

    International Nuclear Information System (INIS)

    Bretscher, M.M.; Oliver, B.M.; Farrar, H. IV.

    1983-01-01

    A tritium extraction facility has been built for the purpose of measuring the absolute tritium concentration in neutron-irradiated lithium metal samples. Two independent calibration procedures have been used to determine what fraction, if any, of tritium is lost during the extraction process. The first procedure compares independently measured 4 He and 3 H concentrations from the 6 Li(n,α)T reaction. The second procedure compared measured 6 Li(n,α)T/ 197 Au (n,γ) 198 Au thermal neutron reaction rate ratios with those obtained from Monte Carlo calculations using well-known cross sections. Both calibration methods show that within experimental errors (approx. 1.5%) no tritium is lost during the extraction process

  2. Tritium glovebox stripper system seismic design evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Grinnell, J. J. [Savannah River Site (SRS), Aiken, SC (United States); Klein, J. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-09-01

    The use of glovebox confinement at US Department of Energy (DOE) tritium facilities has been discussed in numerous publications. Glovebox confinement protects the workers from radioactive material (especially tritium oxide), provides an inert atmosphere for prevention of flammable gas mixtures and deflagrations, and allows recovery of tritium released from the process into the glovebox when a glovebox stripper system (GBSS) is part of the design. Tritium recovery from the glovebox atmosphere reduces emissions from the facility and the radiological dose to the public. Location of US DOE defense programs facilities away from public boundaries also aids in reducing radiological doses to the public. This is a study based upon design concepts to identify issues and considerations for design of a Seismic GBSS. Safety requirements and analysis should be considered preliminary. Safety requirements for design of GBSS should be developed and finalized as a part of the final design process.

  3. Tritium means of detection and of protection

    International Nuclear Information System (INIS)

    Sutra-Fourcade, Y.

    1967-01-01

    The report is an attempt to correlate present data concerning tritium, especially from the health physics points of view. The various detection and measurement methods are reviewed in turn: measurement of tritium in the atmosphere, in liquids and on surfaces. The operation of various types of apparatus is analyzed and the sensitivity limits deduced from laboratory tests are given. Otter sections are devoted to the means of protection which can be used against inhalation of tritium (ventilation, protective clothing) and to calculations of the changes in atmospheric pollution in a given place and of the time spent in a contaminated zone. The last part deals with the decontamination of equipment contaminated with tritium. (author) [fr

  4. Tritium Issues in Next Step Devices

    Energy Technology Data Exchange (ETDEWEB)

    C.H. Skinner; G. Federici

    2001-09-05

    Tritium issues will play a central role in the performance and operation of next-step deuterium-tritium (DT) burning plasma tokamaks and the safety aspects associated with tritium will attract intense public scrutiny. The orders-of-magnitude increase in duty cycle and stored energy will be a much larger change than the increase in plasma performance necessary to achieve high fusion gain and ignition. Erosion of plasma-facing components will scale up with the pulse length from being barely measurable on existing machines to centimeter scale. Magnetic Fusion Energy (MFE) devices with carbon plasma-facing components will accumulate tritium by co-deposition with the eroded carbon and this will strongly constrain plasma operations. We report on a novel laser-based method to remove co-deposited tritium from carbon plasma-facing components in tokamaks. A major fraction of the tritium trapped in a co-deposited layer during the deuterium-tritium (DT) campaign on the Tokamak Fusion Test Reactor (TFTR) was released by heating with a scanning laser beam. This technique offers the potential for tritium removal in a next-step DT device without the use of oxidation and the associated deconditioning of the plasma-facing surfaces and expense of processing large quantities of tritium oxide. The operational lifetime of alternative materials such as tungsten has significant uncertainties due to melt layer loss during disruptions. Production of dust and flakes will need careful monitoring and minimization, and control and accountancy of the tritium inventory will be critical issues. Many of the tritium issues in Inertial Fusion Energy (IFE) are similar to MFE, but some, for example those associated with the target factory, are unique to IFE. The plasma-edge region in a tokamak has greater complexity than the core due to lack of poloidal symmetry and nonlinear feedback between the plasma and wall. Sparse diagnostic coverage and low dedicated experimental run time has hampered the

  5. Tritium Issues in Next Step Devices

    International Nuclear Information System (INIS)

    C.H. Skinner; G. Federici

    2001-01-01

    Tritium issues will play a central role in the performance and operation of next-step deuterium-tritium (DT) burning plasma tokamaks and the safety aspects associated with tritium will attract intense public scrutiny. The orders-of-magnitude increase in duty cycle and stored energy will be a much larger change than the increase in plasma performance necessary to achieve high fusion gain and ignition. Erosion of plasma-facing components will scale up with the pulse length from being barely measurable on existing machines to centimeter scale. Magnetic Fusion Energy (MFE) devices with carbon plasma-facing components will accumulate tritium by co-deposition with the eroded carbon and this will strongly constrain plasma operations. We report on a novel laser-based method to remove co-deposited tritium from carbon plasma-facing components in tokamaks. A major fraction of the tritium trapped in a co-deposited layer during the deuterium-tritium (DT) campaign on the Tokamak Fusion Test Reactor (TFTR) was released by heating with a scanning laser beam. This technique offers the potential for tritium removal in a next-step DT device without the use of oxidation and the associated deconditioning of the plasma-facing surfaces and expense of processing large quantities of tritium oxide. The operational lifetime of alternative materials such as tungsten has significant uncertainties due to melt layer loss during disruptions. Production of dust and flakes will need careful monitoring and minimization, and control and accountancy of the tritium inventory will be critical issues. Many of the tritium issues in Inertial Fusion Energy (IFE) are similar to MFE, but some, for example those associated with the target factory, are unique to IFE. The plasma-edge region in a tokamak has greater complexity than the core due to lack of poloidal symmetry and nonlinear feedback between the plasma and wall. Sparse diagnostic coverage and low dedicated experimental run time has hampered the

  6. Desactivation of tritium waters by rectification methods

    International Nuclear Information System (INIS)

    Egorov, A.I.; Tyunis, V.M.

    2002-01-01

    Results of experiments into the basic rectification processes dedicated to tritium separation from reactor, technological and waste waters are presented. Coefficients of separation for rectification of water (1.028), ammonia (1.05), azeotrope H 2 O - HTO - HNO 3 (1.098) and D 2 O - DTO - DNO 3 (1.039) are performed. Operating schemes of tritium separating units are reviewed [ru

  7. Extraction of tritium from lithium aluminate

    International Nuclear Information System (INIS)

    Yunker, W.

    1976-09-01

    Complete data are presented for the extraction of tritium from neutron irradiated lithium aluminate pellets. Two methods were used: (a) thermal/vacuum extraction at temperatures up to 980 0 C and (b) dissolution of the pellets in sodium tetraborate at 850 0 C followed by vacuum extraction. Approximately 1 percent of the tritium was in a noncondensable (at -195 0 C and 10 -3 torr) form. Extraction efficiency was greater than 95 percent

  8. Extraction of tritium from lithium aluminate

    Energy Technology Data Exchange (ETDEWEB)

    Yunker, W [ed.

    1976-09-01

    Complete data are presented for the extraction of tritium from neutron irradiated lithium aluminate pellets. Two methods were used: (a) thermal/vacuum extraction at temperatures up to 980/sup 0/C and (b) dissolution of the pellets in sodium tetraborate at 850/sup 0/C followed by vacuum extraction. Approximately 1 percent of the tritium was in a noncondensable (at -195/sup 0/C and 10/sup -3/ torr) form. Extraction efficiency was greater than 95 percent.

  9. Enantiospecific tritium labeling of 28-homocastasterone.

    Science.gov (United States)

    Elbert, Tomáš; Patil, Mahadeo R; Marek, Aleš

    2017-03-01

    A regiospecific and enantiospecific synthesis of tritium-labeled 28-homocastasterone is reported. Appropriate chlorocarbonate, efficiently synthesized from the starting 28-homocastasterone in an overall yield of 46%, undergoes catalytic tritium dechlorination by the T 2 /Pd[0]/Et 3 N system, providing 28-[3β- 3 H]homocastasterone, in a good yield, radiochemical purity (>97%), and with a high specific activity (5.8 Ci/mmol). Copyright © 2016 John Wiley & Sons, Ltd.

  10. Energy Metabolism and Human Dosimetry of Tritium

    International Nuclear Information System (INIS)

    Galeriu, D.; Takeda, H.; Melintescu, A.; Trivedi, A.

    2005-01-01

    In the frame of current revision of human dosimetry of 14 C and tritium, undertaken by the International Commission of Radiological Protection, we propose a novel approach based on energy metabolism and a simple biokinetic model for the dynamics of dietary intake (organic 14 C, tritiated water and Organically Bound Tritium-OBT). The model predicts increased doses for HTO and OBT comparing to ICRP recommendations, supporting recent findings

  11. Tritium as a tracer for the movement of surface water and groundwater in the Glatt Valley, Switzerland

    International Nuclear Information System (INIS)

    Santschi, P.H.; Hoehn, E.; Lueck, A.; Farrenkothen, K.

    1987-01-01

    A pulse of tritiated water (∼ 500 Ci) accidentally discharged by an isotope processing plant in the Glatt River Valley, northern Switzerland, allowed us to observe the migration of a contaminant pulse through a sewage treatment plant, rivers, and various wells of infiltrated groundwater. The accident pointed to various memory effects of the tritium, which acted as a conservative tracer. Tritium concentrations in surface water and groundwater were used to test predictions for the transport of conservative anthropogenic trace contaminants accidentally discharged into the sewer system. Mass balance calculations indicate that about 2-10% of the tritium pulse infiltrated to the groundwater and about 0.5% of the total reached eight major drinking water wells of this densely populated area. In spite of the complex hydrogeology of the lower Glatt River Valley, tritium breakthrough curves could be effectively simulated with modeling approaches developed from an experimental well field

  12. Tritons and tritides as the solute and diffusing species in ceramic tritium breeders

    International Nuclear Information System (INIS)

    Fischer, A.K.; Johnson, C.E.

    1987-01-01

    Intragranular diffusion of tritium is an inherent participant in the process of releasing tritium from lithium-containing ceramics that are used to breed tritium in a fusion reactor. The nature of this transport is reviewed in terms of the understanding established for the mechanism of hydrogen migration in other oxides, namely, that the diffusing species is the proton and that it moves from oxide ion to oxide ion, thereby giving rise to apparent hydroxide migration. Analogously, the triton, transiently bonded to successive oxides and forming successive tritoxides, is taken to be the dominant migrating species in ceramic breeders. In addition, tritide becomes a significant participant at low oxygen activity. The relationship of tritons and tritides as the migrating species to the observed release of both reduced and oxidized forms can be understood in terms of the thermodynamic conditions that prevail. Mechanisms exist that can be proposed to rationalize the participation of these species

  13. Utilization of kinetic isotope effects for the concentration of tritium. 1997 annual progress report

    International Nuclear Information System (INIS)

    Brown, G.M.; Meyer, T.J.

    1997-01-01

    'The objective of this research program is to develop methods for concentrating tritium in water based on large primary isotope effects in catalytic redox processes. Basic research is being conducted to develop the chemistry of a complete cyclic process. Because tritium [generally present as tritiated water (HTO)] is in a rapidly established equilibrium with water, it moves with groundwater and separation from water cannot be achieved by the usual pump-and-treat methods using sorbents. The general methodology developed in this work will be applicable to a number of US Department of Energy waste streams, and as a consequence of the process, tritium could be incorporated in an organic polymer, a form that will prevent its ready transport in groundwater.'

  14. Reconstructing Tritium Exposure Using Tree Rings at Lawrence Berkeley National Laboratory, California

    Science.gov (United States)

    LOVE, ADAM H.; HUNT, JAMES R.; KNEZOVICH, JOHN P.

    2010-01-01

    Annual tritium exposures were reconstructed using tree cores from Pinus jeffreyi and Eucalyptus globulus near a tritiated water vapor release stack. Both tritium (3H) and carbon-14 (14C) from the wood were measured from milligram samples using accelerator mass spectrometry. Because the annual nature of the eucalyptus tree rings was in doubt, 14C measurements provided growth rates used to estimate the age for 3H determinations. A 30-yr comparison of organically bound tritium (OBT) levels to reported 3H release data is achieved using OBT measurements from three trees near the stack. The annual average 3H, determined from atmospheric water vapor monitoring stations, is comparable to the OBT in proximal trees. For situations without adequate historical monitoring data, this measurement-based historical assessment provides the only independent means of assessing exposure as compared to fate and transport models that require prior knowledge of environmental conditions and 3H discharge patterns. PMID:14572081

  15. Tritium release from neutron irradiated beryllium pebbles

    Energy Technology Data Exchange (ETDEWEB)

    Scaffidi-Argentina, F.; Werle, H. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer Neutronenphysik und Reactortechnik

    1998-01-01

    One of the most important open issues related to beryllium for fusion applications refers to the kinetics of the tritium release as a function of neutron fluence and temperature. The EXOTIC-7 as well as the `Beryllium` experiments carried out in the HFR reactor in Petten are considered as the most detailed and significant tests for investigating the beryllium response under neutron irradiation. This paper reviews the present status of beryllium post-irradiation examinations performed at the Forschungszentrum Karlsruhe with samples from the above mentioned irradiation experiments, trying to elucidate the tritium release controlling processes. In agreement with previous studies it has been found that release starts at about 500-550degC and achieves a maximum at about 700-750degC. The observed release at about 500-550degC is probably due to tritium escaping from chemical traps, while the maximum release at about 700-750degC is due to tritium escaping from physical traps. The consequences of a direct contact between beryllium and ceramics during irradiation, causing tritium implanting in a surface layer of beryllium up to a depth of about 40 mm and leading to an additional inventory which is usually several times larger than the neutron-produced one, are also presented and the effects on the tritium release are discussed. (author)

  16. Tritium evolution from various morphologies of palladium

    International Nuclear Information System (INIS)

    Tuggle, D.G.; Claytor, T.N.; Taylor, S.F.

    1994-01-01

    The authors have been able to extend the tritium production techniques to various novel morphologies of palladium. These include small solid wires of various diameters and a type of pressed powder wire and a plasma cell. In most successful experiments, the amount of palladium required, for an equivalent tritium output, has been reduced by a factor of 100 over the older powder methods. In addition, they have observed rates of tritium production (>5 nCi/h) that far exceed most of the previous results. Unfortunately, the methods that they currently use to obtain the tritium are poorly understood and consequently there are numerous variables that need to be investigated before the new methods are as reliable and repeatable as the previous techniques. For instance, it seems that surface and/or bulk impurities play a major role in the successful generation of any tritium. In those samples with total impurity concentrations of >400 ppM essentially no tritium has been generated by the gas loading and electrical simulation methods

  17. Separation of tritium from aqueous effluents

    International Nuclear Information System (INIS)

    Bruggeman, A.; Leysen, R.; Meynendonckx, L.; Parmentier, C.; Bellien, H.; Smets, D.; Stevens, J.

    1984-01-01

    This report describes the further development of the so-called ELEX process, carried out from 1 July 1980 until 31 December 1982. The ELEX process is the combination of electrolysis with the catalytic tritium exchange between hydrogen and water in order to accumulate the tritium in the liquid phase. The experimental study of the catalytic tritium exchange between hydrogen and liquid water was continued and the overall exchange rate could be substantially increased. An alternative process based on bithermal exchange of tritium has been evaluated. In the 10 mol h -1 mini-pilot bench scale detritiation unit the ELEX process was successfully demonstrated by detritiating up to now more than 1m 3 of water containing up to 100 mCi tritium per dm 3 , which is the feed concentration to be expected for application of the process in a reprocessing plant. A 280 mol h -1 pilot detritiation installation now being constructed is described. This installation will realize a volume reduction factor of 100 and a process decontamination factor of 100. The maximum total tritium inventory will be about 1000 Ci. The plant consists mainly of a 80 kW electrolyser and a 10 cm diameter exchange column and can be considered as the ultimate step before industrial application of the ELEX process

  18. Experiments on tritium behavior in beryllium, (1)

    International Nuclear Information System (INIS)

    Kawamura, Hiroshi; Ishizuka, Etsuo; Matsumoto, Mikio; Inada, Seiji; Sezaki, Katsuji; Saito, Minoru; Kato, Mineo.

    1989-06-01

    In JMTR, it was observed that the tritium concentration of the primary coolant increases with the reactor operation at 50 MW. As one of the tritium generation sources, we paid attention to a neutron reflector made of beryllium because the tritium generation rate in the beryllium is bigger than other components in the reactor core. On the other hand, the irradiation test of blanket materials (i.e. tritium breeding materials and neutron multipling materials) are planned for development of the fusion reactor in JMTR and the beryllium will be also irradiated as a neutron multiplier with tritium breeding materials. Therefore, as the irradiated specimens, we used a hot-pressed beryllium disk fabricated by the same method as the neutron reflector or the neutron multiplier and conducted the irradiation tests in JMTR. The purpose of these tests are to clarify the tritium behavior in the hot-pressed beryllium. In this paper, from a viewpoint of the fabrication of capsules for neutron irradiation, the specifications of the irradiated specimens and capsules are summarized. Additionally, the results on the puncture test of the container of the irradiation specimens are described. (author)

  19. What is geological entropy and why measure it? A parsimonious approach for predicting transport behaviour in heterogeneous aquifers

    Science.gov (United States)

    Bianchi, Marco; Pedretti, Daniele

    2017-04-01

    We present an approach to predict non-Fickian transport behaviour in alluvial aquifers from knowledge of physical heterogeneity. This parsimonious approach is based on only two measurable parameters describing the global variability and the structure of the hydraulic conductivity (K) field: the variance of the ln(K) values (σY 2), and a newly developed index of geological entropy (HR), based on the concept of Shannon information entropy. Both σY 2 and HR can be obtained from data collected during conventional hydrogeological investigations and from the analysis of a representative model of the spatial distribution of K classes (e.g. hydrofacies) over the domain of interest. The new index HR integrates multiple characteristics of the K field, including the presence of well-connected features, into a unique metric that quantifies the degrees of spatial disorder in the K field structure. Stochastic simulations of tracer tests in synthetic K fields based on realistic distributions of hydrofacies in alluvial aquifers are conducted to identify empirical relations between HR, σY 2, and the first three central temporal moments of the resulting breakthrough curves (BTCs). Results indicate that the first and second moments tend to increase with spatial disorder (i.e, HR increasing). Conversely, high values of the third moment (i.e. skewness), which indicate significant post-peak tailing in the BTCs and non-Fickian transport behaviour, are observed in more orderly structures (i.e, HR decreasing), or for very high σY 2 values. We show that simple closed-form empirical expressions can be derived to describe the bivariate dependency between the skewness of the BTC and corresponding pairs of HR and σY 2. This dependency shows clear correlation for a broad range of structures and Kvariability levels. Therefore, it provides an effective and broadly applicable approach to explain and predict non-Fickian transport in real aquifers, such as those at the well-known MADE site and

  20. Determination of membrane behaviour during transport of pollutants n clay barriers

    International Nuclear Information System (INIS)

    Musso, M.; Pejon, O.

    2010-01-01

    The study of the transport of contaminants in clay barriers had a extensive development in environmental geotechnics. The most studied transport processes are solutes by advection - dispersion and diffusion generated by hydraulic and chemical gradients respectively. Greater attention should be given to the chemical - osmotic flow and behavior membrane clay barriers, since in one case the water molecules move through the existence of a chemical gradient and on the other the means totally or partially inhibits the passage of solutes. The team developed to measure these processes was constructed based on items international literature and performance was verified using two types of materials KCl solution . One material is a bentonite geocomposite (Geosynthetic Clay Liner GCL ) similar to that used by other researchers. The other material is a soil barrier compacted clay (Compacted Clay Liner CCL) Fm. Corumbataí (Permian), belonging to the Paraná basin in the state of Sao Paulo, Brazil . The results show the proper performance of the equipment built . Osmotic pressure generation and membrane performance was verified for both samples. Further corroborated influence of the type of clay mineral in the osmotic pressure generated value and membrane behavior

  1. Tritium behavior in the Caisson, a simulated fusion reactor room

    International Nuclear Information System (INIS)

    Hayashi, Takumi; Kobayashi, Kazuhiro; Iwai, Yasunori; Yamada, Masayuki; Suzuki, Takumi; O'hira, Shigeru; Nakamura, Hirofumi; Shu, Weimin; Yamanishi, Toshihiko; Kawamura, Yoshinori; Isobe, Kanetsugu; Konishi, Satoshi; Nishi, Masataka

    2000-01-01

    In order to confirm tritium confinement ability in the deuterium-tritium (DT) fusion reactor, intentional tritium release experiments have been started in a specially fabricated test stand called 'Caisson', at Tritium Process Laboratory in Japan Atomic Energy Research Institute. The Caisson is a stainless steel leak-tight vessel of 12 m 3 , simulating a reactor room or a tritium handling room. In the first stage experiments, about 260 MBq of pure tritium was put into the Caisson under simulated constant ventilation of four times air exchanges per h. The tritium mixing and migration in the Caisson was investigated with tritium contamination measurement and detritiation behavior measurement. The experimental tritium migration and removal behavior was almost perfectly reproduced and could almost be simulated by a three-dimensional flow analysis code

  2. Studies on steps affecting tritium residence time in solid blanket

    International Nuclear Information System (INIS)

    Tanaka, Satoru

    1987-01-01

    For the self sustaining of CTR fuel cycle, the effective tritium recovery from blankets is essential. This means that not only tritium breeding ratio must be larger than 1.0, but also high recovering speed is required for the short residence time of tritium in blankets. Short residence time means that the tritium inventory in blankets is small. In this paper, the tritium residence time and tritium inventory in a solid blanket are modeled by considering the steps constituting tritium release. Some of these tritium migration processes were experimentally evaluated. The tritium migration steps in a solid blanket using sintered breeding materials consist of diffusion in grains, desorption at grain edges, diffusion and permeation through grain boundaries, desorption at particle edges, diffusion and percolation through interconnected pores to purging stream, and convective mass transfer to stream. Corresponding to these steps, diffusive, soluble, adsorbed and trapped tritium inventories and the tritium in gas phase are conceivable. The code named TTT was made for calculating these tritium inventories and the residence time of tritium. An example of the results of calculation is shown. The blanket is REPUTER-1, which is the conceptual design of a commercial reversed field pinch fusion reactor studied at the University of Tokyo. The experimental studies on the migration steps of tritium are reported. (Kako, I.)

  3. Design options to minimize tritium inventories at Savannah River

    International Nuclear Information System (INIS)

    Klein, J.E.; Wilson, J.; Heroux, K.J.; Poore, A.S.; Babineau, D.W.

    2016-01-01

    Highlights: • La-Ni-Al alloys are used as tritium storage materials and retain He-3. • La-Ni-Al He-3 effects decrease useable process tritium inventory. • Use of Pd or depleted uranium beds decreases process tritium inventories. • Reduced inventory tritium facilities will lower public risk. - Abstract: Large quantities of tritium are stored and processed at the Savannah River Site (SRS) Tritium Facilities. In many design basis accidents (DBAs), it is assumed the entire tritium inventory of the in-process vessels are released from the facility and the site for inclusion in public radiological dose calculations. Pending changes in public dose calculation methodologies are driving the need for smaller in-process tritium inventories to be released during DBAs. Reducing the in-process tritium inventory will reduce the unmitigated source term for public dose calculations and will also reduce the production demand for a lower inventory process. This paper discusses process design options to reduce in-process tritium inventories. A Baseline process is defined to illustrate the impact of removing or replacing La-Ni-Al alloy tritium storage beds with palladium (Pd) or depleted uranium (DU) storage beds on facility in-process tritium inventories. Elimination of La-Ni-Al alloy tritium storage beds can reduce in-process tritium inventories by over 1.5 kg, but alternate process technologies may needed to replace some functions of the removed beds.

  4. The transport behaviour of elemental mercury DNAPL in saturated porous media: Analysis of field observations and two-phase flow modelling

    NARCIS (Netherlands)

    Sweijen, T.; Hartog, Niels; Marsman, A.; Keijzer, T.J.S.

    2014-01-01

    Mercury is a contaminant of global concern. The use of elemental mercury in various (former) industrial processes, such as chlorine production at chlor-alkali plants, is known to have resulted in soil and groundwater contaminations worldwide. However, the subsurface transport behaviour of elemental

  5. Transport Phenomena in Porous Media Aspects of MicroMacro Behaviour

    CERN Document Server

    Ichikawa, Yasuaki

    2012-01-01

    This monograph presents an integrated perspective of the wide range of phenomena and processes applicable to the study of transport of species in porous materials. In order to formulate the entire range of porous media and their uses, this book gives the basics of continuum mechanics, thermodynamics, seepage and consolidation and diffusion, including multiscale homogenization methods. The particular structure of the book has been chosen because it is essential to be aware of the true properties of porous materials particularly in terms of nano, micro and macro mechanisms.  This book is of pedagogical and practical importance to the fields covered by civil, environmental, nuclear and petroleum engineering and also in chemical physics and geophysics as it relates to radioactive waste disposal, geotechnical engineering, mining and petroleum engineering and chemical engineering.

  6. Microbial behaviour and cross contamination between cargoes in containerized transportation of food

    DEFF Research Database (Denmark)

    Abban, Stephen

    contamination scenarios involving both biotic and abiotic surfaces alongside the factors affecting the process have been briefly discussed. Cleaning and disinfection scenarios in related food hygiene environments have been looked into in the literature as well. The experimental work was in several phases...... of construction materials (linings) as well as the need for prompt and effective removal, cleaning and disinfection of residue and pathogens from incidental food contact surfaces in the containers. Measures such as instituting and enforcing HACCP based programs for the container handling operations will also......Transportation is central to the global food and feed supply chain. Thus issues of safety, especially cross contamination with pathogens during food transit should be important in food handling operations. A large proportion of the worlds’ food cargo is moved using intermodal cargo containers...

  7. Incorporation of tritium into planctonic algae in a continuous culture under dynamic conditions

    International Nuclear Information System (INIS)

    Strack, S.; Kistner, G.; Emeis, C.C.

    1979-01-01

    For the purpose of modelling the ecologic behaviour of organically bound tritium (OBT) in aquatic food chains under dynamic conditions (i.e. by changing tritium concentrations), a continuous culture of algae was chosen to which tritium was added by a single injection as tritiated water (HTO). The culture was working according to the chemostatic principle where the concentration of cells is in a steady state. Therefore, according to the growth of algae, tritium is incorporated into the organic substance, while in a parallel process HTO and algae are eliminated from the system at the same rate. From these two processes of first-order kinetics, a special function resulted for the concentration process of OBT in the fermenter that is well known in the field of drug kinetics. Initially it increases until it reaches a maximum value where it intersects the elimination curve of HTO, then decreases and asymptotically approaches the time axis - in the same manner as the elimination curve - only at a superior level. A comparison of this theoretically calculated function with the concentration actually found shows that also under dynamic conditions tritium is undergoing discrimination because of isotopic effects up to a ratio of I=0.80. The calculation of the ratios R=(OBT)/(HTO) in the continuous culture by comparing the function for OBT with the elimination curve for HTO shows a linear increase of R-values during the experiment. At maximum tritium concentration in the algae, the ratio becomes greater than one, and at the end of the experiment it reaches a value of about 6. However, by extrapolating to a time of 40 half-lives, when the absolute concentration of HTO has already decreased by a factor of 10 -12 , a ratio of about 25 was found. The discrimination enters the estimation of R-values at a constant factor of 0.80. (author)

  8. Levels of tritium in soils and vegetation near Canadian nuclear facilities releasing tritium to the atmosphere: implications for environmental models.

    Science.gov (United States)

    Thompson, P A; Kwamena, N-O A; Ilin, M; Wilk, M; Clark, I D

    2015-02-01

    Concentrations of organically bound tritium (OBT) and tritiated water (HTO) were measured over two growing seasons in vegetation and soil samples obtained in the vicinity of four nuclear facilities and two background locations in Canada. At the background locations, with few exceptions, OBT concentrations were higher than HTO concentrations: OBT/HTO ratios in vegetation varied between 0.3 and 20 and values in soil varied between 2.7 and 15. In the vicinity of the four nuclear facilities OBT/HTO ratios in vegetation and soils deviated from the expected mean value of 0.7, which is used as a default value in environmental transfer models. Ratios of the OBT activity concentration in plants ([OBT]plant) to the OBT activity concentration in soils ([OBT]soil) appear to be a good indicator of the long-term behaviour of tritium in soil and vegetation. In general, OBT activity concentrations in soils were nearly equal to OBT activity concentrations in plants in the vicinity of the two nuclear power plants. [OBT]plant/[OBT]soil ratios considerably below unity observed at one nuclear processing facility represents historically higher levels of tritium in the environment. The results of our study reflect the dynamic nature of HTO retention and OBT formation in vegetation and soil during the growing season. Our data support the mounting evidence suggesting that some parameters used in environmental transfer models approved for regulatory assessments should be revisited to better account for the behavior of HTO and OBT in the environment and to ensure that modelled estimates (e.g., plant OBT) are appropriately conservative. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  9. Tritium levels in milk in the vicinity of chronic tritium releases.

    Science.gov (United States)

    Le Goff, P; Guétat, Ph; Vichot, L; Leconte, N; Badot, P M; Gaucheron, F; Fromm, M

    2016-01-01

    Tritium is the radioactive isotope of hydrogen. It can be integrated into most biological molecules. Even though its radiotoxicity is weak, the effects of tritium can be increased following concentration in critical compartments of living organisms. For a better understanding of tritium circulation in the environment and to highlight transfer constants between compartments, we studied the tritiation of different agricultural matrices chronically exposed to tritium. Milk is one of the most frequently monitored foodstuffs in the vicinity of points known for chronic release of radionuclides firstly because dairy products find their way into most homes but also because it integrates deposition over large areas at a local scale. It is a food which contains all the main nutrients, especially proteins, carbohydrates and lipids. We thus studied the tritium levels of milk in chronic exposure conditions by comparing the tritiation of the main hydrogenated components of milk, first, component by component, then, sample by sample. Significant correlations were found between the specific activities of drinking water and free water of milk as well as between the tritium levels of cattle feed dry matter and of the main organic components of milk. Our findings stress the importance of the metabolism on the distribution of tritium in the different compartments. Overall, dilution of hydrogen in the environmental compartments was found to play an important role dimming possible isotopic effects even in a food chain chronically exposed to tritium. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Results of observations of the tritium concentration in water fractions in the disposition regions of tritium laboratories

    International Nuclear Information System (INIS)

    Koval, G.N.; Kuzmina, A.I.; Kolomiets, N.F.; Svarichevskaya, E.V.; Rogosin, V.N.; Svyatun, O.V.

    1995-01-01

    In this paper results of the long term of control of tritium concentration in the water fractions in the region close to the tritium laboratories of INR NAS of Ukraine are presented. The regular observations for the tritium concentration in the water fractions (thawed water of the snow cover, birch juice and sewer water) in the influence region of tritium laboratories shows small amount of tritium concentration in all kinds of investigated water fractions in comparison with the tritium concentration in the reper points. The proper connection of the levels of tritium concentration of the water samples with the quantity of the technology production is observed. In common, the tritium pollution on the territory of INR shows the tendency for a considerable decrease of the environmental pollution levels from year to year. It can be explained by the perfection of the production technology of tritium structures and targets as well as the rising of the qualification of the personnel. 3 refs., 4 figs

  11. Estimating subsurface water volumes and transit times in Hokkaido river catchments, Japan, using high-accuracy tritium analysis

    Science.gov (United States)

    Gusyev, Maksym; Yamazaki, Yusuke; Morgenstern, Uwe; Stewart, Mike; Kashiwaya, Kazuhisa; Hirai, Yasuyuki; Kuribayashi, Daisuke; Sawano, Hisaya

    2015-04-01

    The goal of this study is to estimate subsurface water transit times and volumes in headwater catchments of Hokkaido, Japan, using the New Zealand high-accuracy tritium analysis technique. Transit time provides insights into the subsurface water storage and therefore provides a robust and quick approach to quantifying the subsurface groundwater volume. Our method is based on tritium measurements in river water. Tritium is a component of meteoric water, decays with a half-life of 12.32 years, and is inert in the subsurface after the water enters the groundwater system. Therefore, tritium is ideally suited for characterization of the catchment's responses and can provide information on mean water transit times up to 200 years. Only in recent years has it become possible to use tritium for dating of stream and river water, due to the fading impact of the bomb-tritium from thermo-nuclear weapons testing, and due to improved measurement accuracy for the extremely low natural tritium concentrations. Transit time of the water discharge is one of the most crucial parameters for understanding the response of catchments and estimating subsurface water volume. While many tritium transit time studies have been conducted in New Zealand, only a limited number of tritium studies have been conducted in Japan. In addition, the meteorological, orographic and geological conditions of Hokkaido Island are similar to those in parts of New Zealand, allowing for comparison between these regions. In 2014, three field trips were conducted in Hokkaido in June, July and October to sample river water at river gauging stations operated by the Ministry of Land, Infrastructure, Transport and Tourism (MLIT). These stations have altitudes between 36 m and 860 m MSL and drainage areas between 45 and 377 km2. Each sampled point is located upstream of MLIT dams, with hourly measurements of precipitation and river water levels enabling us to distinguish between the snow melt and baseflow contributions

  12. Method and apparatus for controlling accidental releases of tritium

    Science.gov (United States)

    Galloway, Terry R. [Berkeley, CA

    1980-04-01

    An improvement in a tritium control system based on a catalytic oxidation reactor wherein accidental releases of tritium into room air are controlled by flooding the catalytic oxidation reactor with hydrogen when the tritium concentration in the room air exceeds a specified limit. The sudden flooding with hydrogen heats the catalyst to a high temperature within seconds, thereby greatly increasing the catalytic oxidation rate of tritium to tritiated water vapor. Thus, the catalyst is heated only when needed. In addition to the heating effect, the hydrogen flow also swamps the tritium and further reduces the tritium release.

  13. Method and apparatus for controlling accidental releases of tritium

    International Nuclear Information System (INIS)

    Galloway, T.R.

    1980-01-01

    An improvement in a tritium control system based on a catalytic oxidation reactor is provided wherein accidental releases of tritium into room air are controlled by flooding the catalytic oxidation reactor with hydrogen when the tritium concentration in the room air exceeds a specified limit. The sudden flooding with hydrogen heats the catalyst to a high temperature within seconds, thereby greatly increasing the catalytic oxidation rate of tritium to tritiated water vapor. Thus, the catalyst is heated only when needed. In addition to the heating effect, the hydrogen flow also swamps the tritium and further reduces the tritium release

  14. Analysis of in-pile tritium release experiments

    International Nuclear Information System (INIS)

    Kopasz, J.P.; Tam, S.W.; Johnson, C.E.

    1992-01-01

    The objective of this work is to characterize tritium release behavior from lithium ceramics and develop insight into the underlying tritium release mechanisms. Analysis of tritium release data from recent laboratory experiments with lithium aluminate has identified physical processes which were previously unaccounted for in tritium release models. A new model that incorporates the recent data and provides for release from multiple sites rather than only one site was developed. Calculations of tritium release using this model are in excellent agreement with the tritium release behavior reported for the MOZART experiment

  15. Procedures for the retention of gaseous tritium released from a tritium enrichment plant

    International Nuclear Information System (INIS)

    Gutowski, H.; Bracha, M.

    1987-01-01

    General aim of the study is the comparison of two alternative processes for the retention of gaseous tritium which is released during normal operation and emergency operation in a tritium-enrichment-plant. Two processes for the retention of tritium were compared: 1. Oxidation-process. The hydrogen-gas containing HT will be burnt on an oxidation catalyst to H 2 O and HTO. In a subsequent step the water will be removed from the process by condensation, freezing and adsorption. 2. TROC-process (Tritium Removal by Organic Compounds). The tritium is added to an organic compound (acid) via catalyst. This reaction is irreversible and leads to solid products. (orig./RB) [de

  16. FDNH - the tritium module in RODOS

    International Nuclear Information System (INIS)

    Galeriu, D.; Melintescu, A.; Turcanu, C. O.; Raskob, W.

    2001-01-01

    Under the auspices of its RTD (Research and Technological Development) Framework Programmes, the European Commission has supported the development of the RODOS (Real-time On-line Decision Support) system for off-site emergency management. The project started in 1989 focusing on PWR/LWR type accidents and using experience from the Chernobyl accident. In 1997 it was realised that tritium should be included in the list of radionuclides, as large tritium sources exists in Europe and to allow a potential expansion of the RODOS system for application on future fusion reactor accidents. The National Institute for Physics and Nuclear Engineering (IFIN-HH) in Romania - in close co-operation with the Research Centre Karlsruhe (FZK) - was charged to develop the tritium module, based on previous experience in environmental tritium modelling and the operation of CANDU reactors in Romania (with potential tritium accidents). At present, the Food and Dose Module Hydrogen -(FDMH) - for tritium applications - is integrated and documented in the RODOS system. It calculates the time dependent tritium concentration (as tritiated water or organically bound tritium) in crops (as much as 22 different species) and up to 12 animal products, inhalation doses and ingestion dose from up to 34 diet items for various groups of the population and for up to 2520 locations around the source, following an accidental emission of tritiated water. FDMH incorporates many improved techniques in radiological assessment and makes intensively use of interdisciplinary research. It is developed in a modular structure with a variable time grid according to the physical processes. Differing from other models, using generic transfer parameters or parameters fitted on individual experiments, FDMH derives tritium transfer rates based on physical and physiological process analysis, using scientifically accepted results from interdisciplinary research on, among others, land-atmosphere interaction, water cycle in the

  17. Simulation study of intentional tritium release experiments in the caisson assembly for tritium safety at the TPL/JAERI

    International Nuclear Information System (INIS)

    Iwai, Y.; Hayashi, T.; Kobayashi, K.; Nishi, M.

    2001-01-01

    At the Tritium Process Laboratory (TPL) in Japan Atomic Energy Research Institute (JAERI), Caisson assembly for tritium safety study (CATS) with 12 m 3 of large airtight vessel (Caisson) was fabricated for confirmation and enhancement of fusion reactor safety to estimate the tritium behavior in the case, where the tritium leak accident should happen. One of the principal objectives of the present studies is the establishment of simulation method to predict the tritium behavior after the tritium leak accident should happen in a ventilated room. As for the understanding of initial tritium behavior until the tritium concentration become steady, the precise estimation of local flow rate in a room and time-dependent release behavior from the leak point are essential to predict the tritium behavior by simulation code. The three-dimensional eddy flow model considering, tritium-related phenomena was adopted to estimate the local flow rate in the 50 m 3 /h ventilated Caisson. The time-dependent tritium release behavior from the sample container was calculated by residence time distribution function. The calculated tritium concentrations were in good agreement with the experimental observations. The primary removal tritium behavior was also investigated by another code. Tritium gas concentrations decreased logarithmically to the time by ventilation. These observations were understandable by the reason that the flow in the ventilated Caisson was regarded as the perfectly mixing flow. The concentrations of tritiated water measured, and indications of tritium concentration by tritium monitors became gradually flat. This phenomena called 'tritium soaking effect' was found to be reasonably explained by considering the contribution of the exhaustion velocity by ventilation system, and the adsorption and desorption reaction rate of tritiated water on the wall material which is SUS 304. The calculated tritium concentrations were in good agreement with the experimental observations

  18. A compact tritium AMS system

    International Nuclear Information System (INIS)

    Roberts, M.L.; Hamm, R.W.; Dingley, K.H.; Chiarappa-Zucca, M.L.; Love, A.H.

    2000-01-01

    Tritium ( 3 H) is a radioisotope that is extensively utilized in biological and environmental research. For biological research, 3 H is generally quantified by liquid scintillation counting requiring gram-sized samples and counting times of several hours. For environmental research, 3 H is usually quantified by 3 He in-growth which requires gram-sized samples and in-growth times of several months. In contrast, provisional studies at LLNL's Center for Accelerator Mass Spectrometry have demonstrated that accelerator mass spectrometry (AMS) can be used to quantify 3 H in milligram-sized biological samples with a 100 to 1000-fold improvement in detection limits when compared to scintillation counting. This increased sensitivity is expected to have great impact on the biological and environmental research community. However, in order to make the 3 H AMS technique more broadly accessible, smaller, simpler, and less expensive AMS instrumentation must be developed. To meet this need, a compact, relatively low cost prototype 3 H AMS system has been designed and built based on an LLNL ion source/sample changer and an AccSys Technology radio frequency quadrupole (RFQ) linac. With the prototype system, 3 H/ 1 H ratios ranging from 1x10 -10 to 1x10 -13 have be measured from milligram-sized samples. With improvements in system operation and sample preparation methodology, the sensitivity limit of the system is expected to increase to approximately 1x10 -15

  19. Tritium technology and safety at JET

    International Nuclear Information System (INIS)

    Bell, A.C.

    1994-01-01

    D-T plasma operation has always been envisaged since the beginning of the JET Project and both the original design and subsequent modifications have been designed to take account of the requirements of D-T operation. A limited tritium experiment was carried out in November 1991 which generated 1.7 MW of fusion power. In addition to the physics objectives, this experiment was intended to provide results which would be important for the technology to be used in full D-T phase, such as tritium accounting and hold-up. Because of the limited usage of tritium it was possible to use a open-quotes once-throughclose quotes system in which around 99% of the tritium was recovered. It is currently planned to have a daily throughput of around l0g of tritium per day in the full D-T phase, introduced through neutral beam and/or gas puffing. As it would be neither environmentally acceptable nor cost-effective to discharge even 1% of this to the atmosphere, a tritium recycling plant, known as the Active Gas Handling System (AGHS) has been constructed and is currently being commissioned. It was necessary to take several issues into consideration in the design of the AGHS to ensure that it and the JET machine would be capable of being licensed for handling tritium. These were ensuring that open-quotes Best Practicable Meansclose quotes were used to limit routine discharges to the environment; ensuring that routine radiation exposure of the JET workforce would be minimised; and ensuring that the risk to the workforce and the public arising from accidents would be acceptably low. The technology involved, waste management and regulatory issues are discussed further in the paper

  20. Tritium surveillance around nuclear facilities in Japan

    International Nuclear Information System (INIS)

    Inoue, Y.; Kasida, Y.

    1978-01-01

    In order to measure the tritium levels in the environmental water around the nuclear facilities, the tritium surveillance program began in 1967 locally at Tsuruga and Mihama districts. Nowadays it has been expanded to the ten commercial nuclear power stations and three nuclear facilities. For samples whose tritium concentration is believed less than about 100 pCi/l, they were electrolytically enriched, and then counted by the liquid scintillation counter. Some of samples believed higher than 100 pCi/l were analysed without any enrichment by the low background liquid scintillation counters, Aloka LB 600 or Aloka LB 1. The results of each station are listed in Table. The sampling points corresponding to each results are shown in Figure. Tritium from the effluent was not reflected in all the land water and the tap water around the nuclear power stations and the nuclear facilities. Tritium concentration in rivers, streams, and reservoirs (pools) decreased exponentially from about 600 pCi/l in 1967 to about 150 pCi/l in 1972 at Tsuruga and Mihama, and 360 pCi/l in 1968 to 120 pCi/l in 1973 at Genkai, with the half life of about 2.5 years in both cases. After around 1972, tritium levels of river system in all districts of Japan kept nearly constant up to the end of 1975 and they were in the range from 100 to 300 pCi/l corresponding to the districts. Thereafter, it seems to start to decrease again in 1976. Sea water sampled at the intake of the station or on the seashore far from the outlet was regarded not to be influenced by the effluent from the nuclear reactors or facilities. Tritium concentration in these coastal waters decreased from 100 - 300 pCi/l in 1971 to 30 - 40 pCi/l in 1972 in Fukushima, Ibaraki and Fukui prefectures. (author)

  1. Process and arrangement for the incremental enrichment of deuterium and/or tritium in a material suitable for the isotope exchange of deuterium and/or tritium with hydrogen

    International Nuclear Information System (INIS)

    Iniotakis, N.; vonder Decken, C.-B.

    1985-01-01

    A process for the incremental enrichment of deuterium and/or tritium in a material which is suitable for the isotope exchange of deuterium and tritium with hydrogen, and an arrangement for the implementation of the process. The process and arrangement for the enrichment of deuterium and/or tritium in water which, in addition to a high transport speed for the molecules which participate in the isotope exchange, evidences a high enrichment factor for each enrichment stage and a high yield, so that at a relatively small number of stages and low energy consumption there is attainable an overall high degree of enrichment. For each enrichment stage, water containing deuterium and/or tritium is introduced into a carrier gas flow, reduced and set to a hydrogen (H 2 ) partial pressure of maximally 100 mbar. Subsequent thereto, the carrier gas flow is conveyed along the primary side of an exchange wall which is suitable for the permeation of hydrogen, along the secondary side of which there flow a further carrier gas flow which contains a material adapted for the isotope exchange of deuterium and tritium with hydrogen in the gas phase thereof. The hydrogen isotopes deuterium and/or tritium which permeate through the exchange wall, after the isotope exchange, are bonded with the material in reaction product

  2. Apparent enrichment of organically bound tritium in rivers explained by the heritage of our past.

    Science.gov (United States)

    Eyrolle-Boyer, Frédérique; Boyer, Patrick; Claval, David; Charmasson, Sabine; Cossonnet, Catherine

    2014-10-01

    The global inventory of naturally produced tritium (3H) is estimated at 2.65 kg, whereas more than 600 kg have been released during atmospheric nuclear tests (NCRP, 1979; UNSCEAR, 2000) constituting the main source of artificial tritium throughout the Anthropocene. The behaviour of this radioactive isotope in the environment has been widely studied since the 1950s, both through laboratory experiments and, more recently, through field observations (e.g., Cline, 1953; Kirchmann et al., 1979; Daillant et al., 2004; McCubbin et al., 2001; Kim et al., 2012). In its "free" forms, [i.e. 3H gas or 3H hydride (HT); methyl 3H gas (CH3T); tritiated H2O or 3H-oxide (HTO); and Tissue Free Water 3H (TFWT)], tritium closely follows the water cycle. However, 3H bound with organic compounds, mainly during the basic stages of photosynthesis or through weak hydrogen links, is less exchangeable with water, which explains its persistence in the carbon cycle as re underlined recently by Baglan et al. (2013), Jean-Batiste and Fourré (2013), Kim et al. (2013a,b). In this paper, we demonstrate that terrestrial biomass pools, historically contaminated by global atmospheric fallout from nuclear testing, have constituted a significant delayed source of organically bound tritium (OBT) for aquatic systems, resulting in an apparent enrichment of OBT as compared to HTO. This finding helps to explain concentration factors (tritium concentration in biota/concentration in water) greater than 1 observed in areas that are not directly affected by industrial radioactive wastes, and thus sheds light on the controversies regarding tritium 'bioaccumulation'. Such apparent enrichment of OBT is expected to be more pronounced in the Northern Hemisphere where fallout was most significant, depending on the nature and biodegradability of terrestrial biomass at the regional scale. We further believe that OBT transfers from the continent to oceans have been sufficient to affect tritium concentrations in

  3. Selection of fluids for tritium pumping systems

    International Nuclear Information System (INIS)

    Chastagner, P.

    1984-02-01

    The degradation characteristics of three types of vacuum pump fluids, polyphenyl ethers, perfluoropolyethers and hydrocarbon oils were reviewed. Fluid selection proved to be a critical factor in the long-term performance of tritium pumping systems and subsequent tritium recovery operations. Thermal degradation and tritium radiolysis of pump fluids produce contaminants which can damage equipment and interfere with tritium recovery operations. General characteristics of these fluids are as follows: polyphenyl ether has outstanding radiation resistance, is very stable under normal diffusion pump conditions, but breaks down in the presence of oxygen at anticipated operating temperatures. Perfluoropolyether fluids are very stable and do not react chemically with most gases. Thermal and mechanical degradation products are inert, but the radiolysis products are very corrosive. Most of the degradation products of hydrogen oils are volatile and the principal radiolysis product is methane. Our studies show that polyphenyl ethers and hydrocarbon oils are the preferred fluids for use in tritium pumping systems. No corrosive materials are formed and most of the degradation products can be removed with suitable filter systems

  4. Tritium in the Savannah River Site environment

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, C.E. Jr.; Bauer, L.R.; Hayes, D.W.; Marter, W.L.; Zeigler, C.C.; Stephenson, D.E.; Hoel, D.D.; Hamby, D.M.

    1991-05-01

    Tritium is released to the environment from many of the operations at the Savannah River Site. The releases from each facility to the atmosphere and to the soil and streams, both from normal operations and inadvertent releases, over the period of operation from the early 1950s through 1988 are presented. The fate of the tritium released is evaluated through environmental monitoring, special studies, and modeling. It is concluded that approximately 91% of the tritium remaining after decay is now in the oceans. A dose and risk assessment to the population around the site is presented. It is concluded that about 0.6 fatal cancers may be associated with the tritium released during all the years of operation to the population of about 625,000. This same population (based on the overall US cancer statistics) is expected to experience about 105,000 cancer fatalities from all types of cancer. Therefore, it is considered unlikely that a relationship between any of the cancer deaths occurring in this population and releases of tritium from the SRS will be found.

  5. Experiences with decontaminating tritium-handling apparatus

    International Nuclear Information System (INIS)

    Maienschein, J.L.; Garcia, F.; Garza, R.G.; Kanna, R.L.; Mayhugh, S.R.; Taylor, D.T.

    1991-07-01

    Tritium-handling apparatus has been decontaminated as part of the shutdown of the LLNL Tritium Facility. Two stainless-steel gloveboxes that had been used to process lithium deuteride-tritide (LiDT) salt were decontaminated using the Portable Cleanup System so that they could be flushed with room air through the facility ventilation system. Further surface decontamination was performed by scrubbing the interior with paper towels and ethyl alcohol or Swish trademark. The surface contamination, as shown by swipe surveys, was reduced from 4x10 4 --10 6 disintegrations per minute (dpm)/cm 2 to 2x10 2 --4x10 4 dpm/cm 2 . Details on the decontamination operation are provided. A series of metal (palladium and vanadium) hydride storage beds have been drained of tritium and flushed with deuterium in order to remove as much tritium as possible. The bed draining and flushing procedure is described, and a calculational method is presented which allows estimation of the tritium remaining in a bed after it has been drained and flushed. Data on specific bed draining and flushing are given

  6. Tritium in the Savannah River Site environment

    International Nuclear Information System (INIS)

    Murphy, C.E. Jr.; Bauer, L.R.; Hayes, D.W.; Marter, W.L.; Zeigler, C.C.; Stephenson, D.E.; Hoel, D.D.; Hamby, D.M.

    1991-05-01

    Tritium is released to the environment from many of the operations at the Savannah River Site. The releases from each facility to the atmosphere and to the soil and streams, both from normal operations and inadvertent releases, over the period of operation from the early 1950s through 1988 are presented. The fate of the tritium released is evaluated through environmental monitoring, special studies, and modeling. It is concluded that approximately 91% of the tritium remaining after decay is now in the oceans. A dose and risk assessment to the population around the site is presented. It is concluded that about 0.6 fatal cancers may be associated with the tritium released during all the years of operation to the population of about 625,000. This same population (based on the overall US cancer statistics) is expected to experience about 105,000 cancer fatalities from all types of cancer. Therefore, it is considered unlikely that a relationship between any of the cancer deaths occurring in this population and releases of tritium from the SRS will be found

  7. Tritium and radon risks for humans

    International Nuclear Information System (INIS)

    Mauna, Traian; Mauna, Andriesica

    2008-01-01

    Full text: The gaseous and liquid releases into environment from the two CANDU type units of Cernavoda NPP now in operation has more tritium contents than other kind of western power reactors. CANDU type reactor uses heavy water as moderator and primary circuit heat transfer agent. In normal operation deuterium go to tritium by neutron capture, the molecule of tritiated heavy water can escape from nuclear systems in very small amounts and so it is released into environment. After release the tritium follows the way of water into environment. One year ago the antinuclear NGO led a hard attack against Units 3 and 4 during the procedure of public acceptance request. This attack tried to demonstrate the great risk for humans of the tritium released by Cernavoda NPP. Obviously this risk is very low as demonstrated by many years reactor operation. SNN as owner of Cernavoda NPP ensures by all kind of information channels about the radioactive potential risk for humans. By the other hand, ironically, the antinuclear NGO makes nothing to inform the people about radon risk magnitude in some areas. This is a well-known fact but the radon concentration in dwellings can be decreased by some improved building procedures. The radon is the first natural cause of lung cancer. The environmental NGO and Romanian authorities do not have an information service about radon hazard data neither in dwellings or in uranium mining areas. The paper compares the properties and risks for tritium and radon. (authors)

  8. Radiation-induced tritium labelling and product analysis

    Energy Technology Data Exchange (ETDEWEB)

    Peng, C.T. (California Univ., San Francisco, CA (United States). Dept. of Pharmaceutical Chemistry)

    1993-05-01

    By-products formed in radiation-induced tritium labelling are identified by co-chromatography with authentic samples or by structure prediction using a quantitative structure-retention index relationship. The by-products, formed from labelling of steroids, polynuclear aromatic hydrocarbons, 7-membered heterocyclic ring structures, 1,4-benzodiazepines, 1-haloalkanes, etc. with activated tritium and adsorbed tritium, are shown to be specifically labelled and anticipated products from known chemical reactions. From analyses of the by-products, one can conclude that the hydrogen abstraction by tritium atoms and the substitution by tritium ions are the mechanisms of labelling. Classification of the tritium labelling methods, on the basis of the type of tritium reagent, clearly shows the active role played by tritium atoms and ions in radiation-induced methods. (author).

  9. Mapping of tritium in drinking water from various Indian states

    International Nuclear Information System (INIS)

    Shah, Chirag A.; Baburajan, A.; Ravi, P.M.; Tripathi, R.M.

    2015-01-01

    The tritium in fresh water used for drinking purpose across five state of India was analyzed for tritium activity. The tritium data obtained were compared with the monitoring data of tritium in drinking water sources at Tarapur site, which houses a number of nuclear facilities. It is observed that the tritium activity in the water sample from various out station locations were in the range of < 0.48 to 1.33 Bq/l. The tritium value obtained in the drinking water sources at Tarapur was found to be in the range of 0.91 to 3.10 Bq/l. The monitoring of tritium in drinking water from Tarapur and from various out station location indicate that the level is negligible compared to the USEPA limit of 10000 Bq/l and the contribution of operation nuclear facilities to the tritium activity in drinking water source at Tarapur is insignificant. (author)

  10. Modelization of tritium transfer into the organic compartments of algae

    International Nuclear Information System (INIS)

    Bonotto, S.; Gerber, G.B.; Arapis, G.; Kirchmann, R.

    1982-01-01

    Uptake of tritium oxide and its conversion into organic tritium was studied in four different types of algae with widely varying size and growth characteristics (Acetabularia acetabulum, Boergesenia forbesii, two strains of Chlamydomonas and Dunaliella bioculata). Water in the cell and the vacuales equilibrates rapidly with external tritium water. Tritium is actively incorporated into organically bound form as the organisms grow. During the stationary phase, incorporation of tritium is slow. There exists a discrimination against the incorporation of tritium into organically bound form. A model has been elaborated taking in account these different factors. It appears that transfer of organic tritium by algae growing near the sites of release would be significant only for actively growing algae. Algae growing slowly may, however, be useful as cumulative indicators of discontinuous tritium release. (author)

  11. Tritium activity in Australian rainwater 1962-1986

    International Nuclear Information System (INIS)

    Calf, G.E.

    1988-07-01

    Atmospheric tritirecipitated in rainfall has been measured since 1962 in samples from a network of Australian monitoring stations. Atmospheric thermonuclear bomb tests have injected into the atmosphere about 350 kg of tritium, mostly into the northern hemisphere's troposphere and stratosphere, causing atmospheric concentrations of tritium to reach peak values of 50 to 100 tritium units (TU) in the southern hemisphere. Tritium from underground testing has not contributed significantly to the amounts in the atmosphere or in surface waters. In Australia, peak concentrations of precipitated tritium were observed in 1962, 1964 and 1969. The tritium activity in rainwater for all Australian stations decreased after 1969. Radioactive decay of bomb tritium will decrease the tritium budget to the natural level by the early 1990s in Australian precipitation

  12. Tritium in surface water of the Yenisei river Basin

    International Nuclear Information System (INIS)

    Bondareva, L.G.; Bolsunovsky, A.Ya.

    2005-01-01

    The paper reports an investigation of the tritium content in the surface waters of the Yenisei River basin near the Mining-and-Chemical Combine (MCC). In 2001-2003 the maximum tritium concentration in the Yenisei River did not exceed 4±1 Bq/L. It has been found that there are surface waters containing enhanced tritium, up to 168 Bq/L, as compared with the background values for the Yenisei River. There are two possible sources of tritium input. First, the last operating reactor of the MCC, which still uses the Yenisei water as coolant. Second, tritium may come from the deep aquifers at the Severny testing site. For the first time tritium has been found in two aquatic plant species of the Yenisei River with maximal tritium concentration 304 Bq/Kg wet weight. Concentration factors of tritium for aquatic plants are much higher than 1

  13. Tritium Safety-Related Studies at TPL of JAERI

    Science.gov (United States)

    O'hira, S.; Hayashi, T.; Okuno, K.

    1997-09-01

    Activities regarding tritium safety technology in the Tritium Process Laboratory (TPL) at Tokai Establishment of Japan Atomic Energy Research Institute are reviewed. Research and development of a new tritium removal system is being carried out by using a gas separation membrane which enable to make the ITER atmosphere detritiation system more compact and cost-effective. Techniques of gas flowing calorimetry and laser Raman spectroscopy are applied to develop new tritium accountancy methods. Studies of tritium-material interaction, such as plasma material interactions, radiochemical reaction of tritium in gas phase, radiolysis of tritiated water, and waste processing are being carried out under ITER/EDA and U.S.-Japan collaboration. Tritium release experiments for research of tritium behavior in confinements and environment and demonstration of safety related components are planned.

  14. Transportation behaviour of fluopicolide and its control effect against Phytophthora capsici in greenhouse tomatoes after soil application.

    Science.gov (United States)

    Jiang, Lili; Wang, Hongyan; Xu, Hui; Qiao, Kang; Xia, Xiaoming; Wang, Kaiyun

    2015-07-01

    Fluopicolide, a novel benzamide fungicide, was registered for control of oomycete pathogens, including Phytophthora capsici. In this study, fluopicolide (5% SC) was applied in soil at rates of 1.5, 3 and 6 L ha(-1) [the normal (ND), double (DD) and quadruple dosages (QD) respectively] to investigate its transportation behaviour and control efficiency on tomato blight as a soil treatment agent. The results showed that fluopicolide applied to soil could be absorbed by tomato roots and then transplanted to stems and leaves. It could exist in tomato roots for more than 30 days, and in leaves and stems until day 20 after application. The decline in fluopicolide in soil was in accordance with a first-order dynamics equation, with half-lives of 5.33, 4.75 and 5.42 days for the ND, DD and QD treatments respectively. The control efficiencies of fluopicolide were better with soil application than with spraying application, and the inhibition ratios were 93.02, 97.67 and 100 on day 21 for the ND, DD and QD treatments respectively. Soil application of fluopicolide could control P. capsici in greenhouse tomatoes with high efficiency and long persistence. © 2014 Society of Chemical Industry.

  15. Tritium handling safety and operating experience at the Tritium Systems Test Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, R.V.

    1989-01-01

    The Tritium Systems Test Assembly (TSTA) at Los Alamos National Laboratory is a facility designed to develop and demonstrate, in full scale, technologies necessary for safe and efficient operation of tokamak fusion reactors. TSTA currently consists of systems for pumping DT gas mixtures; for removing impurities; for separating the isotopes of hydrogen; for storage of hydrogen isotopes; for gas analysis; and for assuring safety by the necessary control, monitoring, and detritiation of effluent gaseous streams. TSTA also has several small scale experiments to develop and test new equipment and processes necessary for fusion reactors. Tritium was introduced into TSTA in June 1984. Current inventory is approximately 100 grams. Approximately 10{sup 9} Curies of tritium have been processed in closed loop operation at TSTA. Total tritium releases from the facility stack have been less than 75 Curies. Total operating personnel exposures are less than 500 person-mrem. Exposures to the general public from TSTA tritium releases are extremely small (less than 10{sup {minus}2} mrem). Total tritium buried as waste is less than 36,000 Curies. In this paper, data on component reliability, failure types and rates, and waste quantities are presented. Operational experience under normal, abnormal, and emergency conditions is presented. The DOE requirements for the operation of a tritium facility like TSTA include personnel training, emergency preparedness, radiation protection, safety analysis, and preoperational appraisals. 4 refs., 3 figs., 3 tabs.

  16. The operation of the Tokamak Fusion Test Reactor Tritium Facility

    International Nuclear Information System (INIS)

    Gentile, C.A.; LaMarche, P.H.

    1995-01-01

    The TFTR tritium operations staff has successfully received, stored, handled, and processed over five hundred thousand curies of tritium for the purpose of supporting D-T (Deuterium-Tritium) operations at TFTR. Tritium operations personnel nominally provide continuous round the clock coverage (24 hours/day, 7 days/week) in shift complements consisting of I supervisor and 3 operators. Tritium Shift Supervisors and operators are required to have 5 years of operational experience in either the nuclear or chemical industry and to become certified for their positions. The certification program provides formal instruction, as well as on the job training. The certification process requires 4 to 6 months to complete, which includes an oral board lasting up to 4 hours at which time the candidate is tested on their knowledge of Tritium Technology and TFTR Tritium systems. Once an operator is certified, the training process continues with scheduled training weeks occurring once every 5 weeks. During D-T operations at TFTR the operators must evacuate the tritium area due to direct radiation from TFTR D-T pulses. During '' time operators maintain cognizance over tritium systems via a real time TV camera system. Operators are able to gain access to the Tritium area between TFTR D-T pulses, but have been excluded from die tritium area during D-T pulsing for periods up to 30 minutes. Tritium operators are responsible for delivering tritium gas to TFRR as well as processing plasma exhaust gases which lead to the deposition of tritium oxide on disposable molecular sieve beds (DMSB). Once a DMSB is loaded, the operations staff remove the expended DMSB, and replace it with a new DMSB container. The TFIR tritium system is operated via detailed procedures which require operator sign off for system manipulation. There are >300 procedures controlling the operation of the tritium systems

  17. Technology and component development for a closed tritium cycle

    International Nuclear Information System (INIS)

    Hircq, B.; Penzhorn, R.D.; Haange, R.; Naruse, Y.

    1991-01-01

    A brief summary on recent advances in the field of tritium technology concerning the most important subsystems of the fuel cycle of a fusion reactor, i.e. the plasma exhaust pumping system, the exhaust gas clean up system, the isotope separation, the tritium storage and the tritium extraction from a blanket is provided. Experimental results, single component developments, and technical tests including those with relevants amounts of tritium that constitute the basis of proposed integral process concepts are described. 48 refs

  18. The operation of the Tokamak Fusion Test Reactor Tritium Facility

    Energy Technology Data Exchange (ETDEWEB)

    Gentile, C.A.; LaMarche, P.H. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Anderson, J.L. [Los Alamos National Lab., NM (United States)

    1995-07-01

    The TFTR tritium operations staff has successfully received, stored, handled, and processed over five hundred thousand curies of tritium for the purpose of supporting D-T (Deuterium-Tritium) operations at TFTR. Tritium operations personnel nominally provide continuous round the clock coverage (24 hours/day, 7 days/week) in shift complements consisting of I supervisor and 3 operators. Tritium Shift Supervisors and operators are required to have 5 years of operational experience in either the nuclear or chemical industry and to become certified for their positions. The certification program provides formal instruction, as well as on the job training. The certification process requires 4 to 6 months to complete, which includes an oral board lasting up to 4 hours at which time the candidate is tested on their knowledge of Tritium Technology and TFTR Tritium systems. Once an operator is certified, the training process continues with scheduled training weeks occurring once every 5 weeks. During D-T operations at TFTR the operators must evacuate the tritium area due to direct radiation from TFTR D-T pulses. During `` time operators maintain cognizance over tritium systems via a real time TV camera system. Operators are able to gain access to the Tritium area between TFTR D-T pulses, but have been excluded from die tritium area during D-T pulsing for periods up to 30 minutes. Tritium operators are responsible for delivering tritium gas to TFRR as well as processing plasma exhaust gases which lead to the deposition of tritium oxide on disposable molecular sieve beds (DMSB). Once a DMSB is loaded, the operations staff remove the expended DMSB, and replace it with a new DMSB container. The TFIR tritium system is operated via detailed procedures which require operator sign off for system manipulation. There are >300 procedures controlling the operation of the tritium systems.

  19. Non-labile tritium in Savannah River Plant pine trees

    International Nuclear Information System (INIS)

    Sanders, S.M. Jr.

    1976-06-01

    Non-labile tritium bound in cellulose of pine trees was measured to learn about the effects and fate of tritium contributed to the environment by the Savannah River Plant (SRP). An estimation of the regional inventory and the distance tritium can be observed from SRP was desired because tritium is a major component of the radioactivity released by SRP, and as the oxide, it readily disperses in the environment

  20. Distribution of tritium in a chronically contaminated lake

    International Nuclear Information System (INIS)

    Blaylock, B.G.; Frank, M.L.

    1978-01-01

    White Oak Lake located on the U.S. Department of Energy's Oak Ridge Reservation receives a continuous input of tritium from operating facilities and waste disposal operations at the Oak Ridge National Laboratory. The purpose of this paper was (1) to determine the distribution and concentration of tritium in an aquatic environment which has received releases of tritium significantly greater than expected releases from nuclear power plants, and (2) to determine the effect of fluctuating tritium concentrations in ambient water on the concentration of tritium in fish. Aquatic biota from White Oak Lake were analyzed for tissue water tritium and tissue bound tritium. Except for one plant species, the ratio of tissue water tritium to lake water tritium ranged from 0.80 to 1.02. The tissue water tritium in Gambusia affinis, the mosquito fish, followed closely the significant changes in tritium concentration in lake water. The turnover of tissue water tritium was very rapid; Gambusia from White Oak Lake eliminated 50% of their tissue water tritium in 14 min. The ratio of the specific activity of the tissue bound tritium to the specific activity of the lake water was greatest for the larger species of fish but never exceeded unity. The radiation dose to man from tritium which could be acquired through the aquatic food chain was relatively small when compared to other pathways. The whole body dose to a hypothetical individual taking in concentrations of tritium measured in White Oak Lake was 1.8 mrem/yr from eating fish and 10.0 mrem/yr from drinking water

  1. Evaluation of permeable and non-permeable tritium in normal condition in a fusion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Marta, V; Manuel, P J [Instituto de Fusion Nuclear (DENIM)/ETSII, Universidad Politecnica Madrid (UPM) (Spain); Sedano Luis, A [Ministerio de Educacion y Ciencia, Ciemat (Spain)], E-mail: marta@denim.upm.es

    2008-05-15

    The tritium cycle, technologies of process and control of the tritium in the plant will constitute a fraction of the environmental impact of the first generation of DT fusion reactors. The efforts of conceptual development of the tritium cycle are centered in the Internal Regenerator Cycle. The tritium could be recovered from a flow of He gas, or directly from solid breeder. The limits of transfers to the atmosphere are assumed {approx} 1 gr-T/a ({approx}20 Ci/a) (without species distinction). In the case of ITER, for example, we have global demands of control of 5 orders of magnitude have been demonstrated at experimental level. The transfer limits determine the key parameters in tritium Cycle (HT, HTO, as dominant, and T2, T2O as marginal). Presently, the transfer from the cycle to the environment is assumed through the exchange system of the power plant (primary to secondary). That transport is due to the permeation through HT, T2, or leakage to the coolant in the primary system. It is key the chemical optimization in the primary system, that needs to be reanalyzed in terms of radiological impact both for permeable, HT, T2, and non-permeable HTO, T2O. It is necessary considered the pathway of tritium from the reactor to the atmosphere, these processes are modelled adequately. Results of the assessments were early and chronic doses which have been evaluated for the Most Exposed Individual at particular distance bands from the release point. The impact evaluations will be performed with the computational tools (NORMTRI), besides national regulatory models, internationally accepted computer these code for dosimetric evaluations of tritiated effluents in operational conditions.

  2. Continuous aqueous tritium monitor applying membrane technology

    International Nuclear Information System (INIS)

    Sigg, R.A.

    1992-01-01

    Efforts to develop continuous, real-time tritium monitors are focusing on liquid scintillation (LS) counting because its sensitivity for tritium can be below Environmental Protection Agency guidelines (20 pCi/ml). A flow-through LS counter should have a counting efficiency = 0.48, instrumental backgrounds = 5 count/min counting cell volume = 5 ml, and sample water loading capacities = 15 wt%. The system would offer minimum quantifiable activities at the ±10% level of <18 pCi/ml in a 10-min count or <1 pCi/ml if data are averaged for 1 day. The latter value is below the tritium background of surface waters worldwide. However, good time response in a flow-through LS monitor requires flow rates of at least several milliliters per minute. Such a single-pass system would consume large volumes of expensive LS cocktail, and it would generate notable amounts of mixed organic waste

  3. Low-exposure tritium radiotoxicity in mammals

    International Nuclear Information System (INIS)

    Dobson, R.L.

    1982-01-01

    Studies of tritium radiotoxicity involving chronic 3 H0H exposures in mammals demonstrate in both mice and monkeys that biological effects can be measured following remarkably low levels of exposure - levels in the range of serious practical interest to radiation protection. These studies demonstrate also that deleterious effects of 3 H beta radiation do not differ significantly from those of gamma radiation at high exposures. In contrast, however, at low exposures tritium is significantly more effective than gamma rays, rad for rad, by a factor approaching 3. This is important for hazard evaluation and radiation protection because knowledge concerning biological effects of chronic low-level radiation exposure has come mainly from gamma-ray data; and predictions based on gamma-ray data will underestimate tritium effects - especially at low exposures - unless the RBE is fully taken into account

  4. Advancement Of Tritium Powered Betavoltaic Battery Systems

    Energy Technology Data Exchange (ETDEWEB)

    Staack, G. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Gaillard, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hitchcock, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Peters, B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Colon-Mercado, H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Teprovich, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Coughlin, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Neikirk, K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Fisher, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-10-14

    Due to their decades-long service life and reliable power output under extreme conditions, betavoltaic batteries offer distinct advantages over traditional chemical batteries, especially in applications where frequent battery replacement is hazardous, or cost prohibitive. Although many beta emitting isotopes exist, tritium is considered ideal in betavoltaic applications for several reasons: 1) it is a “pure” beta emitter, 2) the beta is not energetic enough to damage the semiconductor, 3) it has a moderately long half-life, and 4) it is readily available. Unfortunately, the widespread application of tritium powered betavoltaics is limited, in part, by their low power output. This research targets improving the power output of betavoltaics by increasing the flux of beta particles to the energy conversion device (the p-n junction) through the use of low Z nanostructured tritium trapping materials.

  5. Tritium releases, birth defects and infant deaths

    International Nuclear Information System (INIS)

    1991-01-01

    The AECB has published a report 'Tritium releases from the Pickering Nuclear Generating Station and Birth Defects and Infant Mortality in Nearby Communities 1971-1988' (report number INFO-0401). This presents the results of a detailed analysis of deaths and birth defects occurring in infants born to mothers living in the area (25 Km radius) of the Pickering nuclear power plant, over an 18-year period. The analysis looked at the frequency of these defects and deaths in comparison to the general rate for Ontario, and also in relation to airborne and waterborne releases of tritium from the power plant. The overall conclusion was that the rates of infant death and birth defects were generally not higher in the study population than in all of Ontario. There was no prevalent relationship between these deaths and defects and tritium releases measured either at the power plant or by ground monitoring stations t some distance from the facility

  6. Tritium monitoring system for near ambient measurements

    International Nuclear Information System (INIS)

    Falter, K.G.; Bauer, M.L.

    1992-01-01

    This paper describes the current status of research on an improved tritium measurement system at the Oak Ridge National Laboratory (ORNL) for the U.S. Navy. Present tritium-in-air monitoring systems installed by the Navy can reliably measure to less than 10 μCi/m 3 , but medical and safety issues are pushing measurement needs to below 1 μCi/m 3 , which is equivalent to 1-10 nCi/ml in liquid samples, using calcium metal converter. A significant effort has been expended over the past 10 years by the Navy RADIAC Development Program at ORNL on various schemes to improve the detection of tritium in both air and liquid at near ambient levels. One such scheme includes a liquid flow-through system based on an NE102 sponge scintillator with dual photomultiplier tubes for tube noise rejection

  7. Safety analysis of tritium recycling system

    International Nuclear Information System (INIS)

    Yang Yong; Zhang Dong; Xing Shixiong

    2009-04-01

    Safety of a tritium recycling system is analysed according to the structure of the system. The method of accident tree is used to analyse the leakage probability of the system. The result show that the leakage probability of the system failure is 1.1 x 10 -3 and the leakage probability of human fault is 7.2 x 10 -3 , which is are in safe limit. But the leakage probability of human fault is higher than system failure. The MCA will occur because of tritium waste emission cell breakage or misplay, in this case, all tritium in the system will leak, which is about 5.84 TBq. The maximal effective individual dose is 1.24 x 10 -3 mSv, the maximal effective close of the collectivity is 15.33 Person·mSv. (authors)

  8. Tritium in water ecosystems of Ural

    International Nuclear Information System (INIS)

    Chebotina, M.Ya.; Nikolin, O.A.

    2005-01-01

    The paper provides the data on tritium monitoring in water ecosystems of the Ural region. The study area comprises the Beloyarsk Atomic Power Plant (cooling reservoir and the Olkhovsk bog-river ecosystem), a territory around the 'Mayak' Enterprise, and control territory, for comparison, located in the North of Sverdlovsk region. It was found that a large area in the Ural region, particularly near the power plant and the 'Mayak,, was characterized by increased tritium content in water as compared with technogenic background is typical for control areas. It may be considered that nearly all the tritium within the study area including control ones are of anthropogenic origin taking into account the act that the global background level for the radionuclide is 1 Bq/l.(author)

  9. Experiment of hydrogen embrittlement of tritium storage vessel material

    International Nuclear Information System (INIS)

    Jung, Hai Yong; Lee, Kun Jai; Chung, H.; Paek, S.

    2000-01-01

    The tritium storage is one of the most important problems for the safety of tritium removal facility. In current, many researches for tritium immobilization have been carried out. The research for tritium storage could be divided into two parts, one is for the metal getter of tritium and another is for the integrity of tritium storage vessel. Especially, the integrity of tritium storage vessel is up to the tritium embrittlement of vessel material, for tritium vessel is mostly made of metal material. In this work, the evaluation of the tritium embrittlement for the tritium storage vessel material is performed with the equipment that is made for high temperature and high vacuum. However, tritium is the radioactivity material, so hydrogen is used for this work. In this work, three metals were chosen for the vessel candidate material, carbon steel, austenitic stainless steel (SUS) 304 and 316L. The experiment was carried out for the several conditions of temperature and pressure. The property change of metal was investigated through the tensile test. Austenitic stainless steel has a high resistance for the hydrogen embrittlement from the result. But the obvious gap between SUS 304 and SUS 316L is not revealed, because the experiment condition may be not sufficient to show the difference between SUS 304 and SUS 316L

  10. Design and operations at the National Tritium Labelling Facility

    International Nuclear Information System (INIS)

    Morimoto, H.; Williams, P.G.

    1991-09-01

    The National Tritium Labelling Facility (NTLF) is a multipurpose facility engaged in tritium labeling research. It offers to the biomedical research community a fully equipped laboratory for the synthesis and analysis of tritium labeled compounds. The design of the tritiation system, its operations and some labeling techniques are presented

  11. Operating experience and procedures at the tritium systems test assembly

    International Nuclear Information System (INIS)

    Carlson, R.V.; Binning, K.E.; Cole, S.P.; Jenkins, E.M.; Wilhelm, R.C.; Cole, S.P.

    1988-01-01

    Operating procedures are important for the safe and efficient operation of the Tritium Systems Test Assembly (TSTA). TSTA has been operating for four years with tritium in a safe and efficient manner. The inventory of tritium in the process loop is 100 grams and several milestone runs have been completed. This paper describes the methods used to operate TSTA. 3 refs., 1 fig

  12. Preliminary measures of tritium content in the Hague (Cotentin) area

    International Nuclear Information System (INIS)

    Umezu, T.

    1971-01-01

    Tritium content of about thirty samples (seawater, algae and rainwater) taken during April-July 1973 in La Hague (Cotentin) area was determined with a liquid scintillation detector after electrolytic enrichment. Tritium content was 15 to 130 tritium units not much higher than concentration generally observed in environment nowadays [fr

  13. Tritium contamination of concrete walls and floors in tritium-handling laboratory

    International Nuclear Information System (INIS)

    Kawano, T.; Kuroyanagi, M.; Tabei, T.

    2006-01-01

    A tritium handling laboratory was constructed at the National Institute for Fusion Science about twenty years ago and it was recently closed down. We completed the necessary work that is legally required in Japan at the laboratory, when the use of radioisotopes is discontinued, involving measurements of radioactive contamination. We mainly used smear and direct-immersion methods for the measurements. In applying the smear method, we used a piece of filter paper to wipe up the tritium staining the surfaces. The filter paper containing the tritium was placed directly into a dedicated vial, a scintillation cocktail was then poured over it, and the tritium was measured with a liquid scintillation counter. With the direct-immersion method, a piece of concrete was placed directly into a vial containing a scintillation cocktail, and the tritium in the concrete was measured with a liquid scintillation counter. As well as these measurements, we investigated water-extraction and heating-cooling methods for measuring tritium contamination in concrete. With the former, a piece of concrete was placed into water in a tube to extract the tritium, the water containing the extracted tritium was then poured into a dedicated vial containing a scintillation cocktail, and the tritium contamination was measured. With the latter, a piece of concrete was placed into a furnace and heated to 800 degrees centigrade to vaporize the tritiated water into flowing dry air. The flowing air was then cooled to collect the vaporized tritiated water in a tube. The collected water was placed in a vial for scintillation counting. To evaluate the direct-immersion method, ratios were determined by dividing the contamination measured with the heating-cooling method by that measured with the direct-immersion method. The average ratio was about 2.5, meaning a conversion factor from contamination obtained with the direct-immersion method to that with the heating-cooling method. We also investigated the

  14. Tritium Research Laboratory safety analysis report

    International Nuclear Information System (INIS)

    Wright, D.A.

    1979-03-01

    Design and operational philosophy has been evolved to keep radiation exposures to personnel and radiation releases to the environment as low as reasonably achievable. Each experiment will be doubly contained in a glove box and will be limited to 10 grams of tritium gas. Specially designed solid-hydride storage beds may be used to store temporarily up to 25 grams of tritium in the form of tritides. To evaluate possible risks to the public or the environment, a review of the Sandia Laboratories Livermore (SLL) site was carried out. Considered were location, population, land use, meteorology, hydrology, geology, and seismology. The risks and the extent of damage to the TRL and vital systems were evaluated for flooding, lightning, severe winds, earthquakes, explosions, and fires. All of the natural phenomena and human error accidents were considered credible, although the extent of potential damage varied. However, rather than address the myriad of specific individual consequences of each accident scenario, a worst-case tritium release caused indirectly by an unspecified natural phenomenon or human error was evaluated. The maximum credible radiological accident is postulated to result from the release of the maximum quantity of gas from one experiment. Thus 10 grams of tritium gas was used in the analysis to conservatively estimate the maximum whole-body dose of 1 rem at the site boundary and a maximum population dose of 600 man-rem. Accidental release of this amount of tritium implies simultaneous failure of two doubly contained systems, an occurrence considered not credible. Nuclear criticality is impossible in this facility. Based upon the analyses performed for this report, we conclude that the Tritium Research Laboratory can be operated without undue risk to employees, the general public, or the environment

  15. Tritium Research Laboratory safety analysis report

    Energy Technology Data Exchange (ETDEWEB)

    Wright, D.A.

    1979-03-01

    Design and operational philosophy has been evolved to keep radiation exposures to personnel and radiation releases to the environment as low as reasonably achievable. Each experiment will be doubly contained in a glove box and will be limited to 10 grams of tritium gas. Specially designed solid-hydride storage beds may be used to store temporarily up to 25 grams of tritium in the form of tritides. To evaluate possible risks to the public or the environment, a review of the Sandia Laboratories Livermore (SLL) site was carried out. Considered were location, population, land use, meteorology, hydrology, geology, and seismology. The risks and the extent of damage to the TRL and vital systems were evaluated for flooding, lightning, severe winds, earthquakes, explosions, and fires. All of the natural phenomena and human error accidents were considered credible, although the extent of potential damage varied. However, rather than address the myriad of specific individual consequences of each accident scenario, a worst-case tritium release caused indirectly by an unspecified natural phenomenon or human error was evaluated. The maximum credible radiological accident is postulated to result from the release of the maximum quantity of gas from one experiment. Thus 10 grams of tritium gas was used in the analysis to conservatively estimate the maximum whole-body dose of 1 rem at the site boundary and a maximum population dose of 600 man-rem. Accidental release of this amount of tritium implies simultaneous failure of two doubly contained systems, an occurrence considered not credible. Nuclear criticality is impossible in this facility. Based upon the analyses performed for this report, we conclude that the Tritium Research Laboratory can be operated without undue risk to employees, the general public, or the environment. (ERB)

  16. Tritium metrology within different media: focus on organically bound tritium (OBT); Metrologie du tritium dans differentes matrices: cas du tritium organiquement lie (TOL)

    Energy Technology Data Exchange (ETDEWEB)

    Baglan, N. [CEA Bruyeres-le-Chatel, DIF, 91 (France); Ansoborlo, E. [CEA Marcoule, DEN/DRCP/CETAMA, 30 (France); Cossonnet, C. [IRSN, DEI/STEME/LMRE, 91 - Orsay (France); Fouhal, L. [CEA Cadarache, DEN/D2S/LANSE, 13 - Saint-Paul-lez-Durance (France); Deniau, I.; Mokili, M. [SUBATECH/IN2P3/CNRS, 44 - Nantes (France); Henry, A. [AREVA-NC/DQSSE/PR - La Hague, 50 - Beaumont-Hague, (France); Fourre, E. [CEA Saclay, DSM/DRECAM/LSCE, 91 - Gif-sur-Yvette (France); Olivier, A. [GEA-Marine nationale, 50 - Cherbourg (France)

    2010-07-15

    The measurement of tritium in its various forms (mainly gas (HT), water (HTO) or solid (hydrides)), is an important key step for evaluating health and environmental risks and finally, dosimetry assessment. In vegetable or animal samples, tritium is often associated with the free water fraction, but may be included in the organic form as organically bound tritium (OBT). In this case, 2 forms exist: (i) a fraction called exchangeable or labile (E-OBT), bound to oxygen and nitrogen atoms, and (ii) a so-called non-exchangeable fraction (NE-OBT) bound to carbon atoms. The main technique for tritium analysis is liquid scintillation, which enables one to measure concentrations in the range of several Bq.L{sup -1}. The standards (AFNOR, ISO) published to date relate only to tritium analysis in water. Only one CETAMA method addresses OBT analysis in biological environments. This method has been tested since 2001 through intercomparison circuits on grass samples collected from the environment. Regarding tritium analysis in water, the strengths are reliability of this analysis at low concentrations (order of Bq.L{sup -1}), robustness and simplicity, and weaknesses are linked to problems of background, conservation and contamination of samples. Concerning OBT analysis, the analysis is reliable for values around 50 Bq.kg{sup -1} of fresh sample. The weaknesses are problems of contamination, reproducibility, analysis time (2 to 6 days) and lack of reference materials. The difficulty to date is the separation between E-OBT and NE-OBT, that will need experimental validation. (authors)

  17. Decommissioning of a tritium-contaminated laboratory

    International Nuclear Information System (INIS)

    Harper, J.R.; Garde, R.

    1981-11-01

    A tritium laboratory facility at the Los Alamos National Laboratory, Los Alamos, New Mexico, was decommissioned in 1979. The project involved dismantling the laboratory equipment and disposing of the equipment and debris at an on-site waste disposal/storage area. The laboratory was constructed in 1953 and was in service for tritium research and fabrication of lithium tritide components until 1974. The major features of the laboratory included some 25 meters of gloveboxes and hoods, associated vacuum lines, utility lines, exhaust ducts, electrodryers, blowers, and laboratory benches. This report presents details on the decommissioning, health physics, waste management, environmental surveillance, and costs for the operation

  18. Polymeric media for tritium fixation. Supplement I

    International Nuclear Information System (INIS)

    Franz, J.A.; Burger, L.L.

    1976-01-01

    Procedures for the fixation of tritium as TH or THO in two different polymeric media are described. The complete procedure for THO fixation in a polyureylene-polyurethane polumer, including polymer molding procedures and leach tests is presented. The catalytic tritiation of polystyrene under very mild conditions using a rhodium catalyst is also described. Thermal stabilities and cost estimates for the polymers examined under this program are discussed. Organic polymers were found to have attractive features for the fixation and storage of concentrated tritium wastes due to the convenience of fixation procedures and favorable properties of the resulting media

  19. Measurement of tritium in dial painting industry

    International Nuclear Information System (INIS)

    Sawant, J.V.; Rudran, Kamala

    1995-01-01

    Tritium in the form of polystyrene is used coated on zinc sulphide as the active component for the manufacture of self-luminous paint. To study the radiological implication of airborne tritium in the luminous paint industry air monitoring study was conducted by cold strip method and Andersen method. Airborne particulate in different locations in luminous paint (LP) building and background areas were observed to be associated with activity median aerodynamic diameter (AMAD) of 1.8 to 5.0 um. Dose to soft tissue and lungs and effective whole body dose were evaluated. (author). 6 refs., 2 figs., 4 tabs., 2 ills

  20. Tritium projectiles for fueling magnetic fusion plasmas

    International Nuclear Information System (INIS)

    Fisher, P.W.; Gouge, M.J.

    1995-01-01

    As part of the International Thermonuclear Engineering Reactor (ITER) plasma fueling development program, Oak Ridge National Laboratory (ORNL) has fabricated a pellet (cylindrical projectile of frozen hydrogenic gas at a temperature in the range 6--16 K) injection system to test the mechanical and thermal properties of extruded tritium, a radioactive isotope of hydrogen. This repeating, single-stage, pneumatic injector, called the Tritium-Proof-of-Principle Phase 2 (TPOP-2) Pellet Injector, has a piston-driven mechanical extruder and is designed to extrude and accelerate hydrogenic pellets sized for the ITER device. The TPOP-2 program has the following development goals: evaluate the feasibility of extruding tritium and deuterium-tritium (D-T) mixtures for use in future pellet injection systems; determine the mechanical and thermal properties of tritium and D-T extrusions; integrate, test, and evaluate the extruder in a repeating, single-stage light gas gun that is sized for the ITER application (pellet diameter ∼ 7 to 8 mm); evaluate options for recycling propellant and extruder exhaust gas; evaluate operability and reliability of ITER prototypical fueling systems in an environment of significant tritium inventory that requires secondary and room containment systems. In initial tests with deuterium feed at ORNL, up to 13 pellets have been extruded at rates up to 1 Hz and accelerated to speeds of 1.0 to 1.1 km/s, using hydrogen propellant gas at a supply pressure of 65 bar. The pellets, typically 7.4 mm in diameter and up to 11 mm in length, are the largest cryogenic pellets produced by the fusion program to date. These pellets represent about a 11% density perturbation to ITER. Hydrogenic pellets will be used in ITER to sustain the fusion power in the plasma core and may be crucial in reducing first-wall tritium inventories by a process called isotopic fueling in which tritium-rich pellets fuel the burning plasma core and deuterium gas fuels the edge

  1. Development of an environmental tritium model; ETDOSE

    Energy Technology Data Exchange (ETDEWEB)

    Andoh, Mariko; Takahashi, Tomoyuki; Amano, Hikaru [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1999-03-01

    ETDOSE is a simple computer code to calculate atmospheric distribution patterns of tritium for an acute and a chronic release of HT and HTO. This code calculates tritium concentrations in air, soil, plant free water and OBT, and estimates dose impact by inhalation of air and ingestion of food. Participation in IAEA`s model validation program BIOMASS has been done using this code for BIOMASS Scenario 1. This paper shows the outline of ETDOSE and preliminary results of model comparison in BIOMASS program. (author)

  2. Tritium and the environment 3H

    International Nuclear Information System (INIS)

    2002-01-01

    After a presentation of Tritium properties (radioactivity, presence in solids, liquids and gases), this document gives comments and assessments of its natural origin, its presence in relationship with nuclear tests, nuclear power plants, processing plants and other industrial installations, its presence in waters and oceans, in the atmosphere and soils, in plants, animals and mankind. It indicates the main exposure ways (ingestion, inhalation, skin) and its biological effects. It gives an overview of the Tritium-containing waste issue, and indicates some related standards

  3. Report of the Task Group on operation Department of Energy tritium facilities

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This report discusses the following topics on the operation of DOE Tritium facilities: Environment, Safety, and Health Aspects of Tritium; Management of Operations and Maintenance Functions; Safe Shutdown of Tritium Facilities; Management of the Facility Safety Envelope; Maintenance of Qualified Tritium Handling Personnel; DOE Tritium Management Strategy; Radiological Control Philosophy; Implementation of DOE Requirements; Management of Tritium Residues; Inconsistent Application of Requirements for Measurement of Tritium Effluents; Interdependence of Tritium Facilities; Technical Communication among Facilities; Incorporation of Confinement Technologies into New Facilities; Operation/Management Requirements for New Tritium Facilities; and Safety Management Issues at Department of Energy Tritium Facilities.

  4. Description of NORMTRI: a computer program for assessing the off-site consequences from air-borne releases of tritium during normal operation of nuclear facilities

    International Nuclear Information System (INIS)

    Raskob, W.

    1994-10-01

    The computer program NORMTRI has been developed to calculate the behaviour of tritium in the environment released into the atmosphere under normal operation of nuclear facilities. It is possible to investigate the two chemical forms tritium gas and tritiated water vapour. The conversion of tritium gas into tritiated water followed by its reemission back to the atmosphere as well as the conversion into organically bound tritium is considered. NORMTRI is based on the statistical Gaussian dispersion model ISOLA, which calculates the activity concentration in air near the ground contamination due to dry and wet deposition at specified locations in a polar grid system. ISOLA requires a four-parametric meteorological statistics derived from one or more years synoptic recordings of 1-hour-averages of wind speed, wind direction, stability class and precipitation intensity. Additional features of NORMTRI are the possibility to choose several dose calculation procedures, ranging from the equations of the German regulatory guidelines to a pure specific equilibrium approach. (orig.)

  5. The behaviour of transport from the fission products caesium and strontium in coated particles for high temperature reactors under irradiation conditions

    International Nuclear Information System (INIS)

    Zoller, P.

    1976-07-01

    At first survey is given about existing knowledge of the behaviour of caesium and strontium fission product transport in coated particles. In order to describe the complicated fission product transport mechanisms under irradiation conditions a suitable calculating model (SLIPPER) is taken over and modified to the special problems of an irradiation experiment. Fundamentally, the fission product transport is represented by the two contributions of diffusion and recoil, at which the diffusion is described by effective diffusion coefficients. In difference of that the possibility of a two-phase-diffusion is examined for the Cs diffusion in the fuel kernel. The model application on measuring results from irradiation experiments of KFA-Juelich and Mol-Belgien allowed the explanation from the characteristic of fission product transport in coated particles under irradiation conditions and produced effective diffusion coefficients for the fission products Cs and Sr. (orig.) [de

  6. [Mechanism of tritium persistence in porous media like clay minerals].

    Science.gov (United States)

    Wu, Dong-Jie; Wang, Jin-Sheng; Teng, Yan-Guo; Zhang, Ke-Ni

    2011-03-01

    To investigate the mechanisms of tritium persistence in clay minerals, three types of clay soils (montmorillonite, kaolinite and illite) and tritiated water were used in this study to conduct the tritium sorption tests and the other related tests. Firstly, the ingredients, metal elements and heat properties of clay minerals were studied with some instrumental analysis methods, such as ICP and TG. Secondly, with a specially designed fractionation and condensation experiment, the adsorbed water, the interlayer water and the structural water in the clay minerals separated from the tritium sorption tests were fractionated for investigating the tritium distributions in the different types of adsorptive waters. Thirdly, the location and configuration of tritium adsorbed into the structure of clay minerals were studied with infrared spectrometry (IR) tests. And finally, the forces and mechanisms for driving tritium into the clay minerals were analyzed on the basis of the isotope effect of tritium and the above tests. Following conclusions have been reached: (1) The main reason for tritium persistence in clay minerals is the entrance of tritium into the adsorbed water, the interlayer water and the structural water in clay minerals. The percentage of tritium distributed in these three types of adsorptive water are in the range of 13.65% - 38.71%, 0.32% - 5.96%, 1.28% - 4.37% of the total tritium used in the corresponding test, respectively. The percentages are different for different types of clay minerals. (2) Tritium adsorbed onto clay minerals are existed in the forms of the tritiated hydroxyl radical (OT) and the tritiated water molecule (HTO). Tritium mainly exists in tritiated water molecule for adsorbed water and interlayer water, and in tritiated hydroxyl radical for structural water. (3) The forces and effects driving tritium into the clay minerals may include molecular dispersion, electric charge sorption, isotope exchange and tritium isotope effect.

  7. Towards Sustainable Urban Transportation in Ghana: Exploring Adults’ Intention to Adopt Cycling to Work Using Theory of Planned Behaviour and Structural Equation Modelling

    OpenAIRE

    Acheampong, Ransford Antwi

    2017-01-01

    Cycling is considered an environmentally-friendly mode of transport that offers many personal benefits including health, affordability and flexibility of travel. To encourage more people to cycle, especially in contexts where cycle ownership and ridership is considerably low, requires understanding the underlying motivations and barriers to cycling. This study models the behavioural influences of individuals’ (N = 348) intended adoption of cycling to work in the Kumasi metropolis in Ghana, We...

  8. Tritium dynamics in soils and plants at a tritium processing facility in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Mihok, S.; St-Amanat, N.; Kwamena, N.O. [Canadian Nuclear Safety Commission (Canada); Clark, I.; Wilk, M.; Lapp, A. [University of Ottawa (Canada)

    2014-07-01

    The dynamics of tritium released as tritiated water (HTO) have been studied extensively with results incorporated into environmental models such as CSA N288.1 used for regulatory purposes in Canada. The dispersion of tritiated gas (HT) and rates of oxidation to HTO have been studied under controlled conditions, but there are few studies under natural conditions. HT is a major component of the tritium released from a gaseous tritium light manufacturing facility in Canada (CNSC INFO-0798). To support the improvement of models, a garden was set up in one summer near this facility in a spot with tritium in air averaging ∼ 5 Bq/m{sup 3} HTO (passive diffusion monitors). Atmospheric stack releases (575 GBq/week) were recorded weekly. HT releases occur mainly during working hours with an HT:HTO ratio of 2.6 as measured at the stack. Soils and plants (leaves/stems and roots/tubers) were sampled for HTO and organically-bound tritium (OBT) weekly. Active day-night monitoring of air was conducted to interpret tritium dynamics relative to weather and solar radiation. The experimental design included a plot of natural grass/soil, contrasted with grass (sod) and Swiss chard, pole beans and potatoes grown in barrels under different irrigation regimes (in local topsoil at 29 Bq/L HTO, 105 Bq/L OBT). All treatments were exposed to rain (80 Bq/L) and atmospheric releases of tritium (weekdays), and reflux of tritium from soils (initial conditions of 284 Bq/L HTO, 3,644 Bq/L OBT) from 20 years of operations. Three irrigation regimes were used for barrel plants to mimic home garden management: rain only, low tritium tap water (5 Bq/L), and high tritium well water (mean 10,013 Bq/L). This design provided a range of plants and starting conditions with contrasts in initial HTO/OBT activity in soils, and major tritium inputs from air versus water. Controls were two home gardens far from any tritium sources. Active air monitoring indicated that the plume was only occasionally present for

  9. How do firm characteristics affect behavioural additionalities of public R&D subsidies? Evidence for the Austrian transport sector

    OpenAIRE

    Wanzenböck, Iris; Scherngell, Thomas; Fischer, Manfred M.

    2013-01-01

    Interest of STI policies to influence the innovation behaviour of firms has been increased considerably. This gives rise to the notion of behavioural additionality, broadening traditional evaluation concepts of input and output additionality. Though there is empirical work measuring behavioural additionalities, we know little about what role distinct firm characteristics play for their occurrence. The objective is to estimate how distinct firm characteristics influence the realisation of beha...

  10. Development of nuclear micro-battery with solid tritium source

    International Nuclear Information System (INIS)

    Lee, Sook-Kyung; Son, Soon-Hwan; Kim, KwangSin; Park, Jong-Wan; Lim, Hun; Lee, Jae-Min; Chung, Eun-Su

    2009-01-01

    A micro-battery powered by tritium is being developed to utilize tritium produced from the Wolsong Tritium Removal Facility. The 3D p-n junction device has been designed and fabricated for energy conversion. Titanium tritide is adopted to increase tritium density and safety. Sub micron films or nano-powders of titanium tritide is applied on silicon semiconductor device to reduce the self absorption of beta rays. Until now protium has been used instead of tritium for safety. Hydrogen was absorbed up to atomic ratio of ∼1.3 and ∼1.7 in titanium powders and films, respectively.

  11. Quantitative determination of tritium in metals and oxides

    International Nuclear Information System (INIS)

    Vance, D.E.; Smith, M.E.; Waterbury, G.R.

    1979-04-01

    Metallic samples are analyzed for tritium by heating the sample at 1225 K in a moist oxygen stream. The volatile products are trapped and the tritium is quantitatively determined by scintillation spectroscopy. The method is used to determine less than 1 ppb of tritium in 100-mg samples of lithium, iron, nickel, cerium, plutonium, and plutonium dioxide. Analysis of 18 cuts of a tritium-zirconium, copper foil standard over a 3-yr period showed a tritium content of 45 ppM and a standard deviation of 6 ppM

  12. TFTR D-T experience with tritium radioactivity during maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Rule, K.; Gilbert, J.; Ascione, G.; Birckbichler, D.; Elwood, S.; Flournoy, R.; Stencel, J.; Tilson, C. [Princeton Plasma Physics Lab., NJ (United States)

    1995-10-01

    The Tokamak Fusion Test Reactor facility began operations with trace tritium consisting of the delivery, storage, injection, and subsequent processing of tritium gas in support of the D-T fusion program. The tritium is transferred throughout the facility using vacuum pumping systems and expansion volumes. This paper discusses the operational health physics program with regard to the performance of maintenance on tritium contaminated systems. Data and findings are provided from the maintenance situations ranging from work on small volume piping to large volume neutral beam systems. Results and comparisons of the tritium contamination levels, airborne radioactivity levels, and oil concentrations are presented for these systems. 4 refs., 1 fig.

  13. Elements of thought on the health risk associated to tritium

    International Nuclear Information System (INIS)

    2009-01-01

    This report addresses and analyses the health problematic set by tritium and assesses the robustness of the radiation protection system with respect to this radionuclide by highlighting the lack of scientific knowledge on biological effects, and researches to be promoted. After a presentation of epidemiologic and dosimetric approaches of the radiological risk assessment, the authors discuss results and knowledge gained by epidemiologic studies on the risk associated to tritium for mankind, and discuss the knowledge on biological effects of tritium and on the relative biological effectiveness of tritium. The report finally discusses the possibility of reconsidering the radiation weighting factor in the case of tritium

  14. Design of a permeator against vacuum for tritium extraction from eutectic lithium-lead in a DCLL DEMO

    Energy Technology Data Exchange (ETDEWEB)

    Garcinuño, Belit, E-mail: belit.garcinuno@ciemat.es [CIEMAT-LNF (Laboratorio Nacional de Fusión), Madrid (Spain); Rapisarda, David [CIEMAT-LNF (Laboratorio Nacional de Fusión), Madrid (Spain); Fernández, Iván [Fundación & Departamento de Ingeniería Energética, UNED, Madrid (Spain); CIEMAT-LNF (Laboratorio Nacional de Fusión), Madrid (Spain); Moreno, Carlos; Palermo, Iole; Ibarra, Ángel [CIEMAT-LNF (Laboratorio Nacional de Fusión), Madrid (Spain)

    2017-04-15

    Highlights: • A conceptual design of a Permeator Against Vacuum is presented. • The efficiency is dependent on geometry and Tritium transport. • The use of different membrane materials is discussed. • A squared PAV with alternated PbLi flowing and vacuum flat ducts is designed. • 80% efficiency of Tritium extraction is accomplished under DCLL-BB requirements. - Abstract: One of the most important issues in future fusion power plants is the extraction of tritium generated in the breeders in order to achieve self-sufficiency. When the breeder is a liquid metal one of the most promising techniques is the Permeation Against Vacuum, whose principle is based on tritium diffusion through a permeable membrane in contact with the liquid metal carrier and its further extraction by a vacuum pump. A conceptual design of permeator has been developed, taking into account the features of a DEMO reactor with a Dual Coolant Lithium Lead (DCLL) breeder blanket. The study is based on the analysis of different membranes and geometries aiming at the overall efficiency (extraction capability) of the device, as well as its compatibility with the breeder material. The permeator is based on a rectangular section multi-channel distribution where the liquid metal channels and vacuum channels are alternated in order to maximize the contact area and therefore to promote tritium transport from the bulk to the walls. The resulting permeator design has an excellent estimated extraction efficiency, of 80%, in a relatively compact device.

  15. Improving tritium exposure reconstructions using accelerator mass spectrometry

    Science.gov (United States)

    Hunt, J. R.; Vogel, J. S.; Knezovich, J. P.

    2010-01-01

    Direct measurement of tritium atoms by accelerator mass spectrometry (AMS) enables rapid low-activity tritium measurements from milligram-sized samples and permits greater ease of sample collection, faster throughput, and increased spatial and/or temporal resolution. Because existing methodologies for quantifying tritium have some significant limitations, the development of tritium AMS has allowed improvements in reconstructing tritium exposure concentrations from environmental measurements and provides an important additional tool in assessing the temporal and spatial distribution of chronic exposure. Tritium exposure reconstructions using AMS were previously demonstrated for a tree growing on known levels of tritiated water and for trees exposed to atmospheric releases of tritiated water vapor. In these analyses, tritium levels were measured from milligram-sized samples with sample preparation times of a few days. Hundreds of samples were analyzed within a few months of sample collection and resulted in the reconstruction of spatial and temporal exposure from tritium releases. Although the current quantification limit of tritium AMS is not adequate to determine natural environmental variations in tritium concentrations, it is expected to be sufficient for studies assessing possible health effects from chronic environmental tritium exposure. PMID:14735274

  16. Tritium release experiments with CATS and numerical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Munakata, Kenzo, E-mail: kenzo@gipc.akita-u.ac.jp [Faculty of Engineering and Resource Sciences, Akita University, Tegata-gakuen-cho 1-1, Akita 010-8502 (Japan); Wajima, Takaaki; Hara, Keisuke; Wada, Kohei [Faculty of Engineering and Resource Sciences, Akita University, Tegata-gakuen-cho 1-1, Akita 010-8502 (Japan); Takeishi, Toshiharu; Shinozaki, Yohei; Mochizuki, Kazuhiro; Katekari, Kenichi [Interdisciplinary Graduate School of Engineering Science, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581 (Japan); Kobayashi, Kazuhiro; Iwai, Yasunori; Hayashi, Takumi; Yamanishi, Toshihiko [Tritium Technology Group, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan)

    2010-12-15

    In D-T fusion power plants, large amounts of tritium would be handled. Tritium is the radioisotope of protium, and is easily taken into the human body, and thus the behavior of tritium accidentally released in fusion power plants should be studied for the safety design and radioprotection of workers. Therefore, it is necessary to investigate the behavior of tritium released into large rooms with objectives, since complex flow fields should exist in such rooms and they could influence the ventilation of the air containing released tritium. Thus, tritium release experiments were conducted using Caisson Assembly for Tritium Safety Study (CATS) in TPL/JAEA. Some data were taken for tritium behavior in the ventilated area and response of tritium monitors. In the experiments, approximately 17 GBq of tritium was released into Caisson with the total volume of 12 m{sup 3}, and the room was ventilated at the rate of 12 m{sup 3}/h after release of tritium. It was found that placement of an objective in the vessel substantially affects decontamination efficiency. With regard to an experimental result, numerical calculation was performed and the experimental result and the result of numerical calculation were compared, which indicates that experimental results are qualitatively reproduced by numerical calculation. However, further R and D needs to be carried out for quantitative reproduction of the experimental results.

  17. Tritium burning in inertial electrostatic confinement fusion facility

    Energy Technology Data Exchange (ETDEWEB)

    Ohnishi, Masami, E-mail: onishi@kansai-u.ac.jp [Department of Science and Engineering, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan); Yamamoto, Yasushi; Osawa, Hodaka [Department of Science and Engineering, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan); Hatano, Yuji; Torikai, Yuji [Hydrogen Isotope Science Center, University of Toyama, Gofuku, Toyama 930-8555 (Japan); Murata, Isao [Faculty of Engineering Environment and Energy Department, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Kamakura, Keita; Onishi, Masaaki; Miyamoto, Keiji; Konda, Hiroki [Department of Science and Engineering, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan); Masuda, Kai [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Hotta, Eiki [Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259 Nagatsuda-cho, Midori-ku, Yokohama 226-8503 (Japan)

    2016-11-01

    Highlights: • An experiment on tritium burning is conducted in an inertial electrostatic confinement fusion (IECF) facility. • A deuterium–tritium gas mixture with 93% deuterium and 7% tritium is used. • The neutron production rate is measured to be 5–8 times more than that of pure deuterium gas. • The neutron production rate of the D–T gas mixture in 1:1 ratio is expected to be more than 10{sup 8}(1/sec) in the present D–T experiment. - Abstract: An experiment on tritium burning is conducted to investigate the enhancement in the neutron production rate in an inertial electrostatic confinement fusion (IECF) facility. The facility is designed such that it is shielded from the outside for safety against tritium and a getter pump is used for evacuating the vacuum chamber and feeding the fuel gas. A deuterium–tritium gas mixture with 93% deuterium and 7% tritium is used, and its neutron production rate is measured to be 5–8 times more than that of pure deuterium gas. Moreover, the results show good agreement with those of a simplified theoretical estimation of the neutron production rate. After tritium burning, the exhausted fuel gas undergoes a tritium recovery procedure through a water bubbler device. The amount of gaseous tritium released by the developed IECF facility after tritium burning is verified to be much less than the threshold set by regulations.

  18. Preliminary Tritium Management Design Activities at ORNL

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Thomas J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Felde, David K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Logsdon, Randall J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); McFarlane, Joanna [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Qualls, A. L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-09-01

    Interest in salt-cooled and salt-fueled reactors has increased over the last decade (Forsberg et al. 2016). Several private companies and universities in the United States, as well as governments in other countries, are developing salt reactor designs and/or technology. Two primary issues for the development and deployment of many salt reactor concepts are (1) the prevention of tritium generation and (2) the management of tritium to prevent release to the environment. In 2016, the US Department of Energy (DOE) initiated a research project under the Advanced Reactor Technology Program to (1) experimentally assess the feasibility of proposed methods for tritium mitigation and (2) to perform an engineering demonstration of the most promising methods. This document describes results from the first year’s efforts to define, design, and build an experimental apparatus to test potential methods for tritium management. These efforts are focused on producing a final design document as the basis for the apparatus and its scheduled completion consistent with available budget and approvals for facility use.

  19. Installation of the Tritium Purification System

    Energy Technology Data Exchange (ETDEWEB)

    Labik, G.; Golian, T.; Satkofsky, J.; Sichta, P.; Crook, D.; Dudek, L.; Coward, G.; Parsells, R. [Princeton Plasma Physics Lab., NJ (United States)

    1995-12-31

    This paper describes and details the design, the tasks, and the considerations for the mechanical and electrical installation of the TFTR Tritium Purification System (TPS) at the Princeton Plasma Physics Laboratory (PPPL). Canadian Fusion Fuels Technology Project (CFFTP) designed, fabricated, assembled and tested the Tritium Purification System in Ontario, Canada. After system tests were accepted by Princeton Plasma Physics Laboratory, the assembled components were disassembled into a set of subassemblies and were shipped to PPPL. The subassemblies were reassembled at PPPL and installed primarily in the Decon Facility. The original site selection was within the TFTR tritium processing area and that selection impacted the column design. The Decon Facility was later chosen to permit a better layout of equipment and improved access for installation personnel. Selection of the Decon Facility site resulted in longer line runs for most of the process streams including the tritium product line. The initial review of the proposed installation was conducted during September of 1994 and the System Integrated Test began during April 1995, subsequent to a successful Operational Readiness Assessment conducted during March of 1995.

  20. Tritium concentrations in some European foods

    International Nuclear Information System (INIS)

    Hisamatsu, Shun'ichi; Takizawa, Yukio

    1989-01-01

    Tritium concentrations in some European foods imported into Japan are reported here. The specific activity ratio of so-called tissue-bound 3 H to free water 3 H was found to be lower than that previously reported by European and American research groups. This discrepancy might be caused by the difference in sampling year and/or by analytical problems. (author)