WorldWideScience

Sample records for enrichment plants gaseous diffusion

  1. Gaseous diffusion -- the enrichment workhorse

    International Nuclear Information System (INIS)

    Shoemaker, J.E. Jr.

    1984-01-01

    Construction of the first large-scale gaseous diffusion facility was started as part of the Manhattan Project in Oak Ridge, Tennessee, in 1943. This facility, code named ''K-25,'' began operation in January 1945 and was fully on stream by September 1945. Four additional process buildings were later added in Oak Ridge as the demand for enriched uranium escalated. New gaseous diffusion plants were constructed at Paducah, Kentucky, and Portsmouth, Ohio, during this period. The three gaseous diffusion plants were the ''workhorses'' which provided the entire enriched uranium demand for the United States during the 1950s and 1960s. As the demand for enriched uranium for military purposes decreased during the early 1960s, power to the diffusion plants was curtailed to reduce production. During the 1960s, as plans for the nuclear power industry were formulated, the role of the diffusion plants gradually changed from providing highly-enriched uranium for the military to providing low-enriched uranium for power reactors

  2. 78 FR 66779 - United States Enrichment Corporation, Paducah Gaseous Diffusion Plant, Including On-Site Leased...

    Science.gov (United States)

    2013-11-06

    ... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-82,862] United States Enrichment..., applicable to workers of United States Enrichment Corporation, Paducah Gaseous Diffusion Plant, including on... were engaged in the production of low enrichment uranium. The company reports that workers leased from...

  3. EURODIF: the uranium enrichment by gaseous diffusion

    International Nuclear Information System (INIS)

    Rougeau, J.P.

    1981-01-01

    During the seventies the nuclear power programme had an extremely rapid growth rate which entailed to increase the world uranium enrichment capacity. EURODIF is the largest undertaking in this field. This multinational joint venture built and now operates and enrichment plant using the gaseous diffusion process at Tricastin (France). This plant is delivering low enriched uranium since two years and has contracted about 110 million SWU's till 1990. Description, current activity and prospects are given in the paper. (Author) [pt

  4. Natural phenomena hazards evaluation of equipment and piping of Gaseous Diffusion Plant Uranium Enrichment Facility

    International Nuclear Information System (INIS)

    Singhal, M.K.; Kincaid, J.H.; Hammond, C.R.; Stockdale, B.I.; Walls, J.C.

    1995-01-01

    In support of the Gaseous Diffusion Plant Safety Analysis Report Upgrade program (GDP SARUP), a natural phenomena hazards evaluation was performed for the main process equipment and piping in the uranium enrichment buildings at Paducah and Portsmouth gaseous diffusion plants. In order to reduce the cost of rigorous analyses, the evaluation methodology utilized a graded approach based on an experience data base collected by SQUG/EPRI that contains information on the performance of industrial equipment and piping during past earthquakes. This method consisted of a screening walkthrough of the facility in combination with the use of engineering judgment and simple calculations. By using these screenings combined with evaluations that contain decreasing conservatism, reductions in the time and cost of the analyses were significant. A team of experienced seismic engineers who were trained in the use of the DOE SQUG/EPRI Walkdown Screening Material was essential to the success of this natural phenomena hazards evaluation

  5. Natural phenomena hazards evaluation of equipment and piping of Gaseous Diffusion Plant Uranium Enrichment Facility

    Energy Technology Data Exchange (ETDEWEB)

    Singhal, M.K.; Kincaid, J.H.; Hammond, C.R.; Stockdale, B.I.; Walls, J.C. [Oak Ridge National Lab., TN (United States). Technical Programs and Services; Brock, W.R.; Denton, D.R. [Lockheed Martin Energy Systems, Inc., Oak Ridge, TN (United States)

    1995-12-31

    In support of the Gaseous Diffusion Plant Safety Analysis Report Upgrade program (GDP SARUP), a natural phenomena hazards evaluation was performed for the main process equipment and piping in the uranium enrichment buildings at Paducah and Portsmouth gaseous diffusion plants. In order to reduce the cost of rigorous analyses, the evaluation methodology utilized a graded approach based on an experience data base collected by SQUG/EPRI that contains information on the performance of industrial equipment and piping during past earthquakes. This method consisted of a screening walkthrough of the facility in combination with the use of engineering judgment and simple calculations. By using these screenings combined with evaluations that contain decreasing conservatism, reductions in the time and cost of the analyses were significant. A team of experienced seismic engineers who were trained in the use of the DOE SQUG/EPRI Walkdown Screening Material was essential to the success of this natural phenomena hazards evaluation.

  6. Method for estimate the economic characteristics of an uranium enrichment plant by gaseous diffusion

    International Nuclear Information System (INIS)

    Berault, J.C.

    1975-01-01

    To estimate the economic characteristics of an uranium enrichment plant by gaseous diffusion is to determine the prospective price of the separative work unit to which leads the concerned technology, and to collect the data allowing to ascertain that this price remains in the area of development of the prices forecasted by the other projects. The prospective price estimated by the promoter is the synthesis of the components of the go decision and which are a potential market and a comprehensive industrially proven plant design, including the basic economic and technical data of the project. Procedures for estimating these components and their synthesis, exclusive of financing problems are reviewed [fr

  7. Uranium enrichment by the gaseous diffusion process

    International Nuclear Information System (INIS)

    Petit, J.F.

    1977-01-01

    After a brief description of the process and technology (principle, stage constitution, cascade constitution, and description of a plant), the author gives the history of gaseous diffusion and describes the existing facilities. Among the different enrichment processes contemplated in the USA during and after the last world war, gaseous diffusion has been the only one to be developed industrially on a wide scale in the USA, then in the UK, in the USSR and in France. The large existing capacities in the USA provided the country with a good starting base for the development of a light-water nuclear power plant programme, the success of which led to a shortfall in production means. France and the USA, possessing the necessary know-how, have been able to undertake the realization of two industrial programmes: the CIP-CUP programme in the USA and the Eurodif project in France. Current plans still call for the construction of several plants by 1990. Can the gaseous diffusion process meet this challenge. Technically, there is no doubt about it. Economically, this process is mainly characterized by large energy consumption and the necessity to build large plants. This leads to a large investment, at least for the first plant. Other processes have been developed with a view to reducing both energy and capital needs. However, in spite of continuous studies and technological progress, no process has yet proved competitive. Large increments in capacities are still expected to come from gaseous diffusion, and several projects taking into account the improvements in flexibility, automatization, reliability and reduced investment, are analysed in the paper. Combining new facilities with existing plants has already proved to be of great interest. This situation explains why gaseous diffusion is being further investigated and new processes are being studied. (author)

  8. Issues and recommendations related to replacement of CFC-114 at the uranium enrichment gaseous diffusion plant

    International Nuclear Information System (INIS)

    Anderson, B.L.; Banaghan, E.

    1993-01-01

    The operating uranium enrichment gaseous diffusion plants (GDPs) in Portsmouth, Ohio and Paducah, Kentucky, which are operated for the United States Department for Energy by Martin Marietta Energy Systems (MMES), currently use a chlorofluorocarbon (CFC-114) as the primary process stream coolant. Due to recent legislation embodied in the Clean Air Act, the production of this and other related chlorofluorocarbons (CFCS) are to be phased out with no production occurring after 1995. Since the plants lose approximately 500,000 pounds per year of this process stream coolant through various leaks, the GDPs are faced with the challenge of identifying a replacement coolant that will allow continued operation of the plants. MMES formed the CFC Task Team to identify and solve the various problems associated with identifying and implementing a replacement coolant. This report includes a review of the work performed by the CFC Task Team, and recommendations that were formulated based on this review and upon original work. The topics covered include; identifying a replacement coolant, coolant leak detection and repair efforts, coolant safety concerns, coolant level sensors, regulatory issues, and an analytical decision analysis

  9. Uranium enrichment export control guide: Gaseous diffusion

    Energy Technology Data Exchange (ETDEWEB)

    1989-09-01

    This document was prepared to serve as a guide for export control officials in their interpretation, understanding, and implementation of export laws that relate to the Zangger International Trigger List for gaseous diffusion uranium enrichment process components, equipment, and materials. Particular emphasis is focused on items that are especially designed or prepared since export controls are required for these by States that are party to the International Nuclear Nonproliferation Treaty.

  10. 78 FR 65389 - United States Enrichment Corporation, Paducah Gaseous Diffusion Plant

    Science.gov (United States)

    2013-10-31

    ..., USEC notified the NRC of its decision to permanently cease uranium enrichment activities at the PGDP... Accession Nos. ML13105A010 and ML13176A151, respectively. NRC's PDR: You may examine and purchase copies of... in Paducah, Kentucky, using the gaseous [[Page 65390

  11. Simulating Isotope Enrichment by Gaseous Diffusion

    Science.gov (United States)

    Reed, Cameron

    2015-04-01

    A desktop-computer simulation of isotope enrichment by gaseous diffusion has been developed. The simulation incorporates two non-interacting point-mass species whose members pass through a cascade of cells containing porous membranes and retain constant speeds as they reflect off the walls of the cells and the spaces between holes in the membranes. A particular feature is periodic forward recycling of enriched material to cells further along the cascade along with simultaneous return of depleted material to preceding cells. The number of particles, the mass ratio, the initial fractional abundance of the lighter species, and the time between recycling operations can be chosen by the user. The simulation is simple enough to be understood on the basis of two-dimensional kinematics, and demonstrates that the fractional abundance of the lighter-isotope species increases along the cascade. The logic of the simulation will be described and results of some typical runs will be presented and discussed.

  12. The Tricastin gaseous diffusion plant

    International Nuclear Information System (INIS)

    Ergalant, J.; Lebrun, C.; Leduc, C.; Perrault, M.

    1975-01-01

    The building of the EURODIF plant began just over a year ago. The documents on which this enterprise was based were already assembled, which allowed construction work to start without delay. A brief description of the equipment is given, together with an approach to the problems of planning and estimates. Mention is also made of running problems and those related to safety in operation. The present state of the project promises a successful outcome, regarding both the production start-up schedule and the respecting of the building estimate [fr

  13. Technical and economic aspects of new gaseous diffusion uranium enrichment capacity

    International Nuclear Information System (INIS)

    Langley, R.A. Jr.; O'Donnell, A.J.

    1977-01-01

    Work is well advanced on design and construction of the next major increment of U.S. uranium enrichment capacity. The plant will use the gaseous diffusion process to provide the required capacity and reliability at a competitive enrichment services cost. Gaseous diffusion technology is the base against which other processes are compared in order to assess their commercial viability. While it has generally been described as a mature technology with limited future development potential, work on design of the new U.S. plant has resulted in major improvement in plant design with corresponding decreases in plant capacity and operating costs. The paper describes major technological advances incorporated into the new plant design and their impact on enrichment costs. These include the effects of: - advanced barrier technology; - tandem compressor drive systems; - optimization of number of equipment sizes; - single level plant design; - development of rapid power level change capability; - electrical system simplification; - plant arrangement and layout. Resulting capital costs and projected enrichment costs are summarized. Enrichment costs are placed in the context of total nuclear fuel cycle costs. Trade-offs between uranium feed material quantities and enrichment plant tails assays are described, and optimization of this aspect of the nuclear fuel cycle is discussed. The effect on enrichment plant characteristics is described. Flexibility and capability of the new U.S. enrichment plant to meet these changing optimization conditions are described

  14. Plant air systems safety study: Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    1982-05-01

    The Portsmouth Gaseous Diffusion Plant Air System facilities and operations are reviewed for potential safety problems not covered by standard industrial safety procedures. Information is presented under the following section headings: facility and process description (general); air plant equipment; air distribution system; safety systems; accident analysis; plant air system safety overview; and conclusion

  15. Vibration signature analysis of compressors in the gaseous diffusion process for uranium enrichment

    International Nuclear Information System (INIS)

    Harbarger, W.B.

    1975-01-01

    Continuous operation of several thousand axial-flow and centrifugal compressors is vital to the gaseous diffusion process for uranium enrichment. Vibration signature analysis using a minicomputer-based Fast Fourier Transform Analyzer is being applied to the evaluation and surveillance of compressor performance at the Portsmouth Gaseous Diffusion Plant. Three areas of application include: (1) new blade design and prototype compressor evaluation; (2) corrective and preventive maintenance of machinery components; and (3) evaluation of machinery health. The present system is being used to monitor signals from accelerometers mounted on the load-bearing housings of 16 on-line compressors. These signals are transmitted by hard-wire to the analyzer for daily monitoring. A program for expansion of this system to monitor more than a thousand compressors and automation of the signature comparison process is planned for all three gaseous diffusion plants operated for the United States Energy Research and Development Administration. (auth)

  16. Buildup of 236U in the gaseous diffusion plant product

    International Nuclear Information System (INIS)

    Ford, J.S.

    1975-01-01

    A generalized projection of the average annual 236 U concentration that can be expected in future enriched uranium product from the US-ERDA gaseous diffusion plants when reprocessed fuels become available for cascade feeding is given. It is concluded that the buildup of 236 U is not an ever-increasing function, but approaches a limiting value. Projected concentrations result in only slight separative work losses and present no operational problem to ERDA in supplying light water reactor requirements. The use of recycle uranium from power reactor spent fuels will result in significant savings in natural uranium feed

  17. Verification experiment on the downblending of high enriched uranium (HEU) at the Portsmouth Gaseous Diffusion Plant. Digital video surveillance of the HEU feed stations

    International Nuclear Information System (INIS)

    Martinez, R.L.; Tolk, K.; Whiting, N.; Castleberry, K.; Lenarduzzi, R.

    1998-01-01

    As part of a Safeguards Agreement between the US and the International Atomic Energy Agency (IAEA), the Portsmouth Gaseous Diffusion Plant, Piketon, Ohio, was added to the list of facilities eligible for the application of IAEA safeguards. Currently, the facility is in the process of downblending excess inventory of HEU to low enriched uranium (LEU) from US defense related programs for commercial use. An agreement was reached between the US and the IAEA that would allow the IAEA to conduct an independent verification experiment at the Portsmouth facility, resulting in the confirmation that the HEU was in fact downblended. The experiment provided an opportunity for the DOE laboratories to recommend solutions/measures for new IAEA safeguards applications. One of the measures recommended by Sandia National Laboratories (SNL), and selected by the IAEA, was a digital video surveillance system for monitoring activity at the HEU feed stations. This paper describes the SNL implementation of the digital video system and its integration with the Load Cell Based Weighing System (LCBWS) from Oak Ridge National Laboratory (ORNL). The implementation was based on commercially available technology that also satisfied IAEA criteria for tamper protection and data authentication. The core of the Portsmouth digital video surveillance system was based on two Digital Camera Modules (DMC-14) from Neumann Consultants, Germany

  18. Freezer-sublimer for gaseous diffusion plant

    International Nuclear Information System (INIS)

    Reti, G.R.

    1978-01-01

    A method and apparatus is disclosed for freezing and subliming uranium hexafluoride (UF 6 ) as part of a gaseous diffusion plant from which a quantity of the UF 6 inventory is intermittently withdrawn and frozen to solidify it. A plurality of upright heat pipes holds a coolant and is arranged in a two compartment vessel, the lower compartment is exposed to UF 6 , the higher one serves for condensing the evaporated coolant by means of cooling water. In one embodiment, each pipe has a quantity of coolant such as freon, hermetically sealded therein. In the other embodiment, each pipe is sealed only at the lower end while the upper end communicates with a common vapor or cooling chamber which contains a water cooled condenser. The cooling water has a sufficiently low temperature to condense the evaporated coolant. The liquid coolant flows gravitationally downward to the lower end portion of the pipe. UF 6 gas is flowed into the tank where it contacts the finned outside surface of the heat pipes. Heat from the gas evaporates the coolant and the gas in turn is solidified on the exterior of the heat pipe sections in the tank. To recover UF 6 gas from the tank, the solidified UF 6 is sublimed by passing compressed UF 6 gas over the frozen UF 6 gas on the pipes or by externally heating the lower ends of the pipes sufficiently to evaporate the coolant therein above the subliming temperature of the UF 6 . The subliming UF 6 gas then condenses the coolant in the vertical heat pipes, so that it can gravitationally flow back to the lower end portions

  19. Scheduling the maintenance of gaseous diffusion and electric power distribution plants

    International Nuclear Information System (INIS)

    Chauvet, D.

    1990-01-01

    A computer aided scheduling applied to the maintenance of a uranium enrichment plant is presented. The plant exploits gaseous diffusion and electric power distribution plants, for which the operating conditions must be satisfied. The management and the execution of the maintenance actions are computer aided. Concerning the techniques, the cost, the safety and the scheduling actions were optimized [fr

  20. Gaseous diffusion plant transition from DOE to external regulation

    International Nuclear Information System (INIS)

    Dann, R.K.; Crites, T.R.; Rahm-Crites, L.K.

    1997-01-01

    After many years of operation as government-owned/contractor-operated facilities, large portions of the gaseous diffusion plants (GDPs) at Portsmouth, Ohio, and Paducah, Kentucky, were leased to the United States Enrichment Corporation (USEC). These facilities are now certified by the U.S. Nuclear Regulatory Commission (NRC) and subject to oversight by the Occupational Safety and Health Administration (OSHA). The transition from DOE to NRC regulation was more difficult than expected. The original commitment was to achieve NRC certification in October 1995; however, considerably more time was required and transition-related costs escalated. The Oak Ridge Operations Office originally estimated the cost of transition at $60 million; $240 million has been spent to date. The DOE's experience in transitioning the GDPs to USEC operation with NRC oversight provides valuable lessons (both positive and negative) that could be applied to future transitions

  1. Development of on-line uranium enrichment monitor of gaseous UF6 for uranium enrichment plant

    International Nuclear Information System (INIS)

    Lu Xuesheng; Liu Guorong; Jin Huimin; Zhao Yonggang; Li Jinghuai; Hao Xueyuan; Ying Bin; Yu Zhaofei

    2013-01-01

    An on-line enrichment monitor was developed to measure the enrichment of UF 6 , flowing through the processing pipes in uranium enrichment plant. A Nal (Tl) detector was used to measure the count rates of the 185.7 keV γ-ray emitted from 235 U, and the total quantity of uranium was determined from thermodynamic characteristics of gaseous uranium hexafluoride. The results show that the maximum relative standard deviation is less than 1% when the measurement time is 120 s or more and the pressure is more than 2 kPa in the measurement chamber. Uranium enrichment of gaseous uranium hexafluoride in the output end of cascade can be monitored continuously by using the device. It should be effective for nuclear materials accountability verifications and materials balance verification at uranium enrichment plant. (authors)

  2. Radioactive effluents, Portsmouth Gaseous Diffusion Plant, calendar year 1982

    International Nuclear Information System (INIS)

    Acox, T.A.; Hary, L.F.; Klein, L.S.

    1983-03-01

    Radioactive discharges from the Portsmouth Gaseous Diffusion Plant are discussed and tabulated. Tables indicate both the location of the discharge and the nuclides discharged. All discharges for 1982 are well below the Radioactive Concentration Guide limits specified in DOE Order 5480.1, Chapter XI. 1 figure

  3. Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1977-09-01

    Volume 1 is comprised of chapters on: background and description; environmental impacts of add-on gaseous diffusion plant; unavoidable adverse environmental effects; alternatives; relationship between short-term uses and long-term productivity; relationship of program to land-use plans, policies, and controls; irreversible and irretrievable commitments of resources; cost-benefit analysis; and response to comment letters. (LK)

  4. Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 1

    International Nuclear Information System (INIS)

    1977-09-01

    Volume 1 is comprised of chapters on: background and description; environmental impacts of add-on gaseous diffusion plant; unavoidable adverse environmental effects; alternatives; relationship between short-term uses and long-term productivity; relationship of program to land-use plans, policies, and controls; irreversible and irretrievable commitments of resources; cost-benefit analysis; and response to comment letters

  5. IAEA verification experiment at the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Gordon, D.M.; Subudhi, M.; Calvert, O.L.; Bonner, T.N.; Cherry, R.C.; Whiting, N.E.

    1998-01-01

    In April 1996, the United States (US) added the Portsmouth Gaseous Diffusion Plant to the list of facilities eligible for the application of International Atomic Energy Agency (IAEA) safeguards. At that time, the US proposed that the IAEA carry out a Verification Experiment at the plant with respect to the downblending of about 13 metric tons of highly enriched uranium (HEU) in the form of UF 6 . This material is part of the 226 metric tons of fissile material that President Clinton has declared to be excess to US national-security needs and which will be permanently withdrawn from the US nuclear stockpile. In September 1997, the IAEA agreed to carry out this experiment, and during the first three weeks of December 1997, the IAEA verified the design information concerning the downblending process. The plant has been subject to short-notice random inspections since December 17, 1997. This paper provides an overview of the Verification Experiment, the monitoring technologies used in the verification approach, and some of the experience gained to date

  6. Hierarchical optimization in isotope separation-gaseous diffusion: plant, cascade, stage, principles, and applications

    Energy Technology Data Exchange (ETDEWEB)

    Guais, J. C.

    1975-09-01

    The large scale system represented by a gaseous diffusion plant model, and its hierarchical mathematical structure are the reasons for a decomposition method, minimizing the total cost of enrichment. This procedure has been used for years in the optimization problems of the french projects.

  7. Hierarchical optimization in isotope separation. Gaseous diffusion: plant, cascade, stage. Principles and applications

    International Nuclear Information System (INIS)

    Guais, J.C.

    1975-01-01

    The large scale system represented by a gaseous diffusion plant model, and its hierarchical mathematical structure are the reasons for a decomposition method, minimizing the total cost of enrichment. This procedure has been used for years in the optimization problems of the french projects [fr

  8. Portsmouth Gaseous Diffusion Plant expansion, Piketon, Ohio. Volume 2. Draft environmental statement

    Energy Technology Data Exchange (ETDEWEB)

    Pennington, W. H.

    1976-06-01

    The need for additional uranium enrichment facilities and the environmental impacts of the add-on gaseous diffusion plant proposed for the Portsmouth Gaseous Diffusion Plant are discussed. A detailed description of the proposed facilities is included and unavoidable adverse environmental effects, possible alternatives, and anticipated benefits from the proposed facilities are considered. The flora and fauna of the area are tabulated and possible effects of air and water pollution on aquatic and terrestrial ecosystems are postulated. The extent of anticipated noise impact on the vicinity and the anticipated extent of civic envolvement are discussed. (CH)

  9. Portsmouth Gaseous Diffusion Plant expansion, Piketon, Ohio. Volume 2. Draft environmental statement

    International Nuclear Information System (INIS)

    1976-06-01

    The need for additional uranium enrichment facilities and the environmental impacts of the add-on gaseous diffusion plant proposed for the Portsmouth Gaseous Diffusion Plant are discussed. A detailed description of the proposed facilities is included and unavoidable adverse environmental effects, possible alternatives, and anticipated benefits from the proposed facilities are considered. The flora and fauna of the area are tabulated and possible effects of air and water pollution on aquatic and terrestrial ecosystems are postulated. The extent of anticipated noise impact on the vicinity and the anticipated extent of civic envolvement are discussed

  10. Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 2. Appendices

    International Nuclear Information System (INIS)

    1977-09-01

    Volume 2 is comprised of appendices: Portsmouth Gaseous Diffusion Plant Existing Facilities; Ecology; Civic Involvement; Social Analysis; Population Projections; Toxicity of Air Pollutants to Biota at Portsmouth Gaseous Diffusion Plant; and Assessment of Noise Effects of an Add-On to the Portsmouth Gaseous Diffusion Plant

  11. Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 2. Appendices. [Appendices only

    Energy Technology Data Exchange (ETDEWEB)

    Liverman, James L.

    1977-09-01

    Volume 2 is comprised of appendices: Portsmouth Gaseous Diffusion Plant Existing Facilities; Ecology; Civic Involvement; Social Analysis; Population Projections; Toxicity of Air Pollutants to Biota at Portsmouth Gaseous Diffusion Plant; and Assessment of Noise Effects of an Add-On to the Portsmouth Gaseous Diffusion Plant. (LK)

  12. Paducah Gaseous Diffusion Plant Environmental report for 1990

    Energy Technology Data Exchange (ETDEWEB)

    Counce-Brown, D. (ed.)

    1991-09-01

    This two-part report, Paducah Gaseous Diffusion Plant Site Environmental Report for 1990, is published annually. It reflects the results of a comprehensive, year-round program to monitor the impact of operations at Paducah Gaseous Diffusion Plant (PGDP) on the area's groundwater and surface waters, soil, air quality, vegetation, and wildlife. In addition, an assessment of the effect of PGDP effluents on the resident human population is made. PGDP's overall goal for environmental management is to protect the environment and PGDP's neighbors and to maintain full compliance with all current regulations. The current environmental strategy is to identify any deficiencies and to develop a system to resolve them. The long-range goal of environmental management is to minimize the source of pollutants, to reduce the formation of waste, and to minimize hazardous waste by substitution of materials.

  13. Paducah Gaseous Diffusion Plant environmental report for 1992

    Energy Technology Data Exchange (ETDEWEB)

    Horak, C.M. [ed.] [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

    1993-09-01

    This two-part report, Paducah Gaseous Diffusion Plant Environmental Report for 1992, is published annually. It reflects the results of an environmental monitoring program designed to quantify potential increases in the concentration of contaminants and potential doses to the resident human population. The Paducah Gaseous Diffusion Plant (PGDP) overall goal for environmental management is to protect the environment and PGDP`s neighbors and to maintain full compliance with all current regulations. The current environmental strategy is to identify any deficiencies and to develop a system to resolve them. The long-range goal of environmental management is to minimize the source of pollutants, reduce the generation of waste, and minimize hazardous waste by substitution of materials.

  14. Paducah Gaseous Diffusion Plant environmental report for 1992

    International Nuclear Information System (INIS)

    Horak, C.M.

    1993-09-01

    This two-part report, Paducah Gaseous Diffusion Plant Environmental Report for 1992, is published annually. It reflects the results of an environmental monitoring program designed to quantify potential increases in the concentration of contaminants and potential doses to the resident human population. The Paducah Gaseous Diffusion Plant (PGDP) overall goal for environmental management is to protect the environment and PGDP's neighbors and to maintain full compliance with all current regulations. The current environmental strategy is to identify any deficiencies and to develop a system to resolve them. The long-range goal of environmental management is to minimize the source of pollutants, reduce the generation of waste, and minimize hazardous waste by substitution of materials

  15. Research and economic evaluation on uranium enrichment by gaseous diffusion process in Japan

    International Nuclear Information System (INIS)

    Aochi, T.; Takahashi, S.

    1977-01-01

    Research and development works on uranium enrichment by gaseous diffusion process were carried out by JAERI, IPCR and industries since 1965. There are two important keys to reduce the uranium separation cost. One is the characteristics of the barrier and the other is financing and/or political planning. The technics to prepare the barrier with pore diameter of 40A have been developed with polytetrafluoroethylene, alumina and nickel. The experiment on corrosion behavior of PTFE barriers has shown better characteristics than the others. In the field of engineering research, the adiabatic efficiency of axial compressor for UF 6 was resulted to as high as 90% by long term operation tests. Based on these experimental data, techno-economic evaluation on a uranium enrichment plant was carried out with regard to the optimization of separation efficiency, numbers of step and operating conditions of the plant. Sensitivity in the separation cost were calculated as a function of pore diameter, uranium hexafluoride cost, plant capacity, electric power cost, and the plant annual expenditure. A financing plan must be such as to achieve 1. maximization of debt in a percentage of total capitalization 2. off-take contracts to utilities as security for financing 3. minimization of risks to equity and achievable cost of capital. Therefore the cash flow analysis and the schedule for construction and operation are very important for a economical feasibility of a uranium enrichment plant. To minimize the risk, not only economical but also political environment are important. The governmental supports and international agreements will be necessary

  16. Research on and economic evaluation of uranium enrichment by gaseous diffusion in Japan

    International Nuclear Information System (INIS)

    Aochi, T.; Takahashi, S.

    1977-01-01

    Research and development on uranium enrichment by the gaseous diffusion process have been carried out by the Japan Atomic Energy Research Institute, the Institute of Physical and Chemical Research, and industries since 1965. The paper describes the two important keys to reducing the cost of uranium separation. One is the characteristics of barriers and the other is financing and/or political planning. The techniques of preparing a barrier with pore diameter 40A have been developed with polytetrafluoroethylene (PTFE), alumina and nickel. Experiments on corrosion behaviour have indicated that PTFE barriers are the most favourable. In the field of engineering research, the adiabatic efficiency of the axial compressor for UF 6 was raised to as high as 90% by long-term operation tests. Based on these experimental data, technico-economic evaluation of a uranium enrichment plant was carried out for optimization of separation efficiency, number of steps and plant operating conditions. Sensitivity in the separation cost was calculated as a function of pore diameter, cost of uranium hexafluoride, plant capacity, cost of electric power, and annual expenditure of the plant. A finance plan must be such as to achieve: (a) maximization of debt in a percentage of total capital; (b) off-take contracts to utilities as security for financing; (c) minimization of risks to equity and achievable cost of capital. Therefore, the cash flow analysis and the schedule for construction and operation are very important for the economic feasibility of a uranium enrichment plant. To minimize the risk, the economic as well as the political environment is important. Government support and international agreements are necessary. (author)

  17. Reliability study: maintenance facilities Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Post, B.E.; Sikorski, P.A.; Fankell, R.; Johnson, O.; Ferryman, D.S.; Miller, R.L.; Gearhart, E.C.; Rafferty, M.J.

    1981-08-01

    A reliability study of the maintenance facilities at the Portsmouth Gaseous Diffusion Plant has been completed. The reliability study team analyzed test data and made visual inspections of each component contributing to the overall operation of the facilities. The impacts of facilities and equipment failures were given consideration with regard to personnel safety, protection of government property, health physics, and environmental control. This study revealed that the maintenance facilities are generally in good condition. After evaluating the physical condition and technology status of the major components, the study team made several basic recommendations. Implementation of the recommendations proposed in this report will help assure reliable maintenance of the plant through the year 2000

  18. Prioritizing and scheduling Portsmouth Gaseous Diffusion Plant safeguards upgrades

    International Nuclear Information System (INIS)

    Edmunds, T.; Saleh, R.; Zevanove, S.

    1992-02-01

    As part of the Site Safeguards and Security Plan (SSSP), facilities are required to develop a Resource Plan (RP). The Resource Plan provides documentation and justification for the facility's planned upgrades, including the schedule, priority, and cost estimates for the safeguards and security upgrades. Portsmouth Gaseous Diffusion Plant (PORTS) management has identified and obtained funding approval for a number of safeguards and security upgrades, including line-item construction projects. These upgrade projects were selected to address a variety of concerns identified in the PORTS vulnerability assessments and other reviews performed in support of the SSSP process. However, budgeting and scheduling constraints do not make it possible to simultaneously begin implementation of all of the upgrade projects. A formal methodology and analysis are needed to explicitly address the trade-offs between competing safeguards objectives, and to prioritize and schedule the upgrade projects to ensure that the maximum benefit can be realized in the shortest possible time frame. The purpose of this report is to describe the methodology developed to support these upgrade project scheduling decisions. The report also presents the results obtained from applying the methodology to a set of the upgrade projects selected by PORTS S ampersand S management. Data for the analysis are based on discussions with personnel familiar with the PORTS safeguards and security needs, the requirements for implementing these upgrades, and upgrade funding limitations. The analysis results presented here assume continued highly enriched uranium (HEU) operations at PORTS. However, the methodology developed is readily adaptable for the evaluation of other operational scenarios and other resource allocation issues relevant to PORTS

  19. Portsmouth Gaseous Diffusion Plant environmental report for 1992

    International Nuclear Information System (INIS)

    Horak, C.M.

    1993-09-01

    This calendar year (CY) 1992 annual report on environmental surveillance of the US Department of Energy's (DOE's) Portsmouth Gaseous Diffusion Plant (PORTS) and its environs consists of two parts: narrative, summaries, and conclusions (Part 1) and data presentation (Part 2). The objectives of this report are to: (1) report 1992 monitoring data for the installation and its environs that may have been affected by operations on the plant site, (2) provide reasonably detailed information about the plant site and plant operations, (3) provide detailed information on input and assumptions used in all calculations, (4) provide trend analyses (where appropriate) to indicate increases and decreases in environmental impact, and (5) provide general information on plant quality assurance

  20. Portsmouth Gaseous Diffusion Plant Environmental report for 1990

    Energy Technology Data Exchange (ETDEWEB)

    Counce-Brown, D. (ed.)

    1991-09-01

    This calendar year 1990 annual report on environmental surveillance of the US Department of Energy's (DOE's) Portsmouth Gaseous Diffusion Plant (PORTS) and its environs consists of two parts: the summary, discussion, and conclusions (Part 1) and the data presentation (Part 2). The objectives of this report are as follows: report 1990 monitoring data for the installation and its environs that may have been affected by operations on the plant site, provide reasonably detailed information about the plant site and plant operations, provide detailed information on input and assumptions used in all calculations, provide trend analyses (when appropriate) to indicate increases and decreases in environmental impact, and provide general information on plant quality assurance.

  1. Paducah Gaseous Diffusion Plant Annual Site Environmental Report for 1993

    International Nuclear Information System (INIS)

    1994-10-01

    The purpose of this document is to summarize effluent monitoring and environmental surveillance results and compliance with environmental laws, regulations, and orders at the Paducah Gaseous Diffusion Plant (PGDP). Environmental monitoring at PGDP consists of two major activities: effluent monitoring and environmental surveillance. Effluent monitoring is direct measurement or the collection and analysis of samples of liquid and gaseous discharges to the environment. Environmental surveillance is direct measurement or the collection and analysis of samples of air, water, soil, foodstuff, biota, and other media. Environmental monitoring is performed to characterize and quantify contaminants, assess radiation exposures of members of the public, demonstrate compliance with applicable standards and permit requirements, and detect and assess the effects (if any) on the local environment. Multiple samples are collected throughout the year and are analyzed for radioactivity, chemical content, and various physical attributes

  2. Portsmouth Gaseous Diffusion Plant annual site environmental report for 1993

    Energy Technology Data Exchange (ETDEWEB)

    Horak, C.M. [ed.

    1994-11-01

    This calendar year (CY) 1993 annual report on environmental monitoring of the US Department of Energy`s (DOE`s) Portsmouth Gaseous Diffusion Plant (Portsmouth) and its environs consists of three separate documents: a summary pamphlet for the general public; a more detail discussion and of compliance status, data, and environmental impacts (this document); and a volume of detailed data that is available on request. The objectives of this report are to report compliance status during 1993; provide information about the plant site and plant operations; report 1993 monitoring data for the installation and its environs that may have been affected by operations on the plant site; document information on input and assumptions used in calculations; provide trend analyses (where appropriate) to indicate increases and decreases in environmental impact, and provide general information on quality assurance for the environmental monitoring program.

  3. Portsmouth Gaseous Diffusion Plant annual site environmental report for 1993

    International Nuclear Information System (INIS)

    Horak, C.M.

    1994-11-01

    This calendar year (CY) 1993 annual report on environmental monitoring of the US Department of Energy's (DOE's) Portsmouth Gaseous Diffusion Plant (Portsmouth) and its environs consists of three separate documents: a summary pamphlet for the general public; a more detail discussion and of compliance status, data, and environmental impacts (this document); and a volume of detailed data that is available on request. The objectives of this report are to report compliance status during 1993; provide information about the plant site and plant operations; report 1993 monitoring data for the installation and its environs that may have been affected by operations on the plant site; document information on input and assumptions used in calculations; provide trend analyses (where appropriate) to indicate increases and decreases in environmental impact, and provide general information on quality assurance for the environmental monitoring program

  4. Portsmouth Gaseous Diffusion Plant expansion, Piketon, Ohio. Volume 1. Draft environmental statement

    International Nuclear Information System (INIS)

    1976-06-01

    Subject to authorizing legislation and funding, ERDA will proceed with steps for additional uranium enrichment capacity at the Portsmouth Gaseous Diffusion Plant near Piketon, Ohio. This environmental statement was prepared by ERDA to cover this action. The statement was prepared in accordance with the National Environmental Policy Act of 1969, and ERDA's implementing regulations, 10 CFR Chapter III, Part 711. The statement describes the reasonably foreseeable environmental, social, economic and technological costs and benefits of the construction and operation of the expanded enrichment plant and its reasonably available alternatives and their anticipated effects

  5. Portsmouth Gaseous Diffusion Plant expansion, Piketon, Ohio. Volume 1. Draft environmental statement

    Energy Technology Data Exchange (ETDEWEB)

    1976-06-01

    Subject to authorizing legislation and funding, ERDA will proceed with steps for additional uranium enrichment capacity at the Portsmouth Gaseous Diffusion Plant near Piketon, Ohio. This environmental statement was prepared by ERDA to cover this action. The statement was prepared in accordance with the National Environmental Policy Act of 1969, and ERDA's implementing regulations, 10 CFR Chapter III, Part 711. The statement describes the reasonably foreseeable environmental, social, economic and technological costs and benefits of the construction and operation of the expanded enrichment plant and its reasonably available alternatives and their anticipated effects.

  6. Control of technetium at the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Saraceno, A.J.

    1981-01-01

    Technetium-99 entered the gaseous diffusion complex as a volatile impurity in recycled uranium that was fed to the Paducah Gaseous Diffusion Plant. Subsequently, it entered the Oak Ridge and Portsmouth cascades as an impurity in Paducah product feed. Most of the technetium was adsorbed on cascade equipment in increasingly high concentrations as it moved up the cascade. Since the low energy beta radiation produced by technetium cannot penetrate cascade equipment, it presents no significant hazard to workers as long as it remains inside of equipment. However, when equipment that contains high concentrations of technetium is opened for maintenance or change-out, precautions are taken to ensure worker safety. Traps containing activated alumina are used at the plant vent streams to limit radioactive emissions as far as possible. Annual vent stream emissions have been well below DOE limits. To allow continued compliance, other potential trapping agents have been tested. Several that limit emissions more effectively than activated alumina have been found. Other traps containing magnesium fluoride are used in the upper cascade to reduce the technetium concentration. Waste solutions from decontamination can also contain technetium. These solutions must either be stored for controlled discharge or treated to remove the technetium. To allow the latter, an ion exchange facility is being installed for operation by the end of FY-1982. Liquid discharges at Portsmouth have usually been less than 5% of the DOE imposed limits

  7. Gaseous diffusion system

    International Nuclear Information System (INIS)

    Garrett, G.A.; Shacter, J.

    1978-01-01

    A gaseous diffusion system is described comprising a plurality of diffusers connected in cascade to form a series of stages, each of the diffusers having a porous partition dividing it into a high pressure chamber and a low pressure chamber, and means for combining a portion of the enriched gas from a succeeding stage with a portion of the enriched gas from the low pressure chamber of each stage and feeding it into one extremity of the high pressure chamber thereof

  8. Measurement of the Portsmouth Gaseous Diffusion Plant criticality accident alarm

    International Nuclear Information System (INIS)

    Tayloe, R.W. Jr.; McGinnis, B.

    1990-01-01

    Measurements of the Portsmouth Gaseous Diffusion Plant's nuclear criticality accident radiation alarm signal response time, sound wave frequency, and sound volume levels were made to demonstrate compliance with ANSI/ANS-8.3-1986. A steady-state alarm signal is produced within one-half second of obtaining a two-out-of-three detector trip. The fundamental alarm sound wave frequency is 440 hertz. The sound volume levels are greater than 10 decibels above background and ranged from 100 to 125 A-weighted decibels. The requirements of the standard were met; however the recommended maximum sound volume level of 115 dBA was exceeded. Emergency procedures require immediate evacuation upon initiation of a facility's radiation alarm. Comparison with standards for allowable time of exposure at different noise levels indicate that the elevated noise level at this location does not represent an occupational injury hazard. 8 refs., 5 figs

  9. Paducah Gaseous Diffusion Plant environmental report for 1989

    Energy Technology Data Exchange (ETDEWEB)

    Turner, J.W. (ed.) (Martin Marietta Energy Systems, Inc., Oak Ridge, TN (USA))

    1990-10-01

    This two-part environmental report is published annually. It reflects the results of a comprehensive, year-round program to monitor the impact of operations at Paducah Gaseous Diffusion Plant (PGDP) on the area's groundwater and surface waters, soil, air quality, vegetation, and wildlife. In addition, an assessment of the effect of PGDP effluents on the resident human population is made. PGDP's overall goal for environmental management is to protect the environment and PGDP's neighbors and to maintain full compliance with all current regulations. The current environmental strategy is to identify any deficiencies and to develop a system to resolve them. The long-range goal of environmental management is to minimize the source of pollutants, to reduce the formation of waste, and to minimize hazardous waste by substitution of materials. 36 refs.

  10. Portsmouth Gaseous Diffusion Plant environmental report for 1989

    Energy Technology Data Exchange (ETDEWEB)

    Turner, J.W. (ed.) (Martin Marietta Energy Systems, Inc., Oak Ridge, TN (USA))

    1990-10-01

    This calendar year 1989 annual report on environmental surveillance of the US Department of Energy's (DOE) Portsmouth Gaseous Diffusion Plant (PORTS) and its environs consists of two parts: the Summary, Discussion, and Conclusions (Part 1) and the Data Presentation (Part 2). The objectives of this report are the following: report 1989 monitoring data for the installation and its environs that may have been affected by operations on the plant site, provide reasonably detailed information about the plant site and plant operations, provide detailed information on input and assumptions used in all calculations, provide trend analyses (where appropriate) to indicate increases and decreases in environmental impact, and provide general information on plant quality assurance. Routine monitoring and sampling for radiation, radioactive materials, and chemical substances on and off the DOE site are used to document compliance with appropriate standards, to identify trends, to provide information for the public, and to contribute to general environmental knowledge. The surveillance program assists in fulfilling the DOE policy of protecting the public, employees, and environment from harm that could be caused by its activities and reducing negative environmental impacts to the greatest degree practicable. Environmental-monitoring information complements data on specific releases, trends, and summaries. 26 refs.

  11. Raffinate treatment at the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Acox, T.A.

    1983-01-01

    Raffinate solutions, which contain uranium, technetium, nitrates, and lesser amounts of heavy metals, are produced in the decontamination and uranium recovery operations at the Portsmouth Gaseous Diffusion Plant. These solutions are presently being placed in temporary storage until three treatment facilities are constructed which will produce an environmentally acceptable effluent from the raffinate. These facilities are: (1) The Heavy Metals Precipitation Facility; (2) The Technetium Ion Exchange Facility; and (3) The Biodenitrification Pilot Plant. When the facilities are completed, the raffinate will be treated in 500 gallon batches. The first treatment is the heavy metals precipitation by caustic addition and filtering. The effluent proceeds to the ion exchange columns where the technetium is removed by adsorption onto a strongly basic, anion exchange resin which has been converted to the hydroxyl form. Following ion exchange, the solution is transported to the biodenitrification pilot plant. The biodenitrification column is a fluidized-bed using bacteria-laden coal particles as the denitrifying media. The resulting effluent should meet the limits established by the US EPA for all metals and nitrate. Technetium will be 98+% removed and the uranium concentration will be less than one milligram per liter. 13 references

  12. The Blend Down Monitoring System Demonstration at the Padijcah Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Benton, J.; Close, D.; Johnson, W. Jr.; Kerr, P.; March-Leuba, J.; Mastal, E.; Moss, C.; Powell, D.; Sumner, J.; Uckan, T.; Vines, R.; Wright, P.D.

    1999-01-01

    Agreements between the governments of the US and the Russian Federation for the US purchase of low enriched uranium (LEU) derived from highly enriched uranium (HEU) from dismantled Russian nuclear weapons calls for the establishment of transparency measures to provide confidence that nuclear nonproliferation goals are being met. To meet these transparency goals, the agreements call for the installation of nonintrusive US instruments to monitor the down blending of HEU to LEU. The Blend Down Monitoring System (BDMS) has been jointly developed by the Los Alamos National Laboratory (LANL) and the Oak Ridge National Laboratory (ORNL) to continuously monitor 235 U enrichments and mass flow rates at Russian blending facilities. Prior to its installation in Russian facilities, the BDMS was installed and operated in a UF 6 flow loop in the Paducah Gaseous Diffusion Plant simulating flow and enrichment conditions expected in a typical down-blending facility. A Russian delegation to the US witnessed the equipment demonstration in June, 1998. To conduct the demonstration in the Paducah Gaseous Diffusion Plant (PGDP), the BDMS was required to meet stringent Nuclear Regulatory Commission licensing, safety and operational requirements. The Paducah demonstration was an important milestone in achieving the operational certification for the BDMS use in Russian facilities

  13. Uranium deposit removal from the Oak Ridge Gaseous Diffusion Plant K-25 Building

    International Nuclear Information System (INIS)

    Ladd, L.D.; Stinnett, E.C. Jr.; Hale, J.R.; Haire, M.J.

    1993-01-01

    The Oak Ridge Gaseous Diffusion Plant went into operation as the first plant to separate uranium by the gaseous diffusion process. It was built during World War II as part of the U.S. Army Corps of Engineers' Manhattan Project. Its war-time code name was K-25, which was also the name of the first uranium separation building constructed at the installation. The K-25 building was considered an engineering miracle at the time of its construction. Built in a U shape ∼1 mile long and 400 ft wide, it housed complex and unique separation equipment. Despite its size and complexity, it was made fully operational within <2 yr after construction began. The facility operated successfully for more than 20 yr until it was placed in a standby mode in 1964. It is now clear the K-25 gaseous diffusion plant will never again be used to enrich uranium. The U.S. Department of Energy, therefore, has initiated a decontamination and decommission program. This paper discusses various procedures and techniques for addressing critical mass, uranium deposits, and safeguards issues

  14. Measurement of the Portsmouth Gaseous Diffusion Plant criticality accident alarm

    International Nuclear Information System (INIS)

    Tayloe, R.W. Jr.; D'Aquila, D.M.; McGinnis, R.B.

    1991-01-01

    The nuclear criticality accident radiation alarm system installed at the Portsmouth Gaseous Diffusion Plant was tested extensively at critical facilities located at the Los Alamos National Laboratory. The ability of the neutron scintillator radiation detection units to respond to a minimum accident of concern as defined in Standard ANSI/ANS-83.-1986 was demonstrated. Detector placement and the established trip point are based on shielding calculations performed by the Oak Ridge National Laboratory and criticality specialists at the Portsmouth plant. Based on these experiments and calculations, a detector trip point of 5 mrad/h in air is used. Any credible criticality accident is expected to produce neutron radiation fields >5 mrad/h in air at one or more radiation alarm locations. Each radiation alarm location has a cluster of three detectors that employs a two-out-of-three alarm logic. Earlier work focused on testing the alarm logic latching circuitry. This work was directed toward measurements involving the actual audible alarm signal delivered

  15. Air sampling program at the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Hulett, S.H.

    1975-01-01

    An extensive air sampling program has been developed at the Portsmouth Gaseous Diffusion Plant for monitoring the concentrations of radioactive aerosols present in the atmosphere on plantsite as well as in the environs. The program is designed to minimize exposures of employees and the environment to airborne radioactive particulates. Five different air sampling systems, utilizing either filtration or impaction, are employed for measuring airborne alpha and beta-gamma activity produced from 235 U and 234 Th, respectively. Two of the systems have particle selection capabilities: a personal sampler with a 10-mm nylon cyclone eliminates most particles larger than about 10 microns in diameter; and an Annular Kinetic Impactor collects particulates greater than 0.4 microns in diameter which have a density greater than 12-15 gm/cm 3 . A Hi-Volume Air Sampler and an Eberline Model AIM-3 Scintillation Air Monitor are used in collecting short-term samples for assessing compliance with ''ceiling'' standards or peak concentration limits. A film-sort aperture IBM card system is utilized for continuous 8-hour samples. This sampling program has proven to be both practical and effective for assuring accurate monitoring of the airborne activity associated with plant operations

  16. Exposure to recycled uranium contaminants in gaseous diffusion plants

    International Nuclear Information System (INIS)

    Anderson, Jeri L.; Yiin, James H.; Tseng, Chih-Yu; Apostoaei, A. Iulian

    2017-01-01

    As part of an ongoing study of health effects in a pooled cohort of gaseous diffusion plant workers, organ dose from internal exposure to uranium was evaluated. Due to the introduction of recycled uranium into the plants, there was also potential for exposure to radiologically significant levels of "9"9Tc, "2"3"7Np and "2"3"8","2"3"9Pu. In the evaluation of dose response, these radionuclide exposures could confound the effect of internal uranium. Using urine bioassay data for study subjects reported in facility records, intakes and absorbed dose to bone surface, red bone marrow and kidneys were estimated as these organs were associated with a priori outcomes of interest. Additionally, "9"9Tc intakes and doses were calculated using a new systemic model for technetium and compared to intakes and doses calculated using the current model recommended by the International Commission on Radiological Protection. Organ absorbed doses for the transuranics were significant compared to uranium doses; however, "9"9Tc doses calculated using the new systemic model were significant as well. Use of the new model resulted in an increase in "9"9Tc-related absorbed organ dose of a factor of 8 (red bone marrow) to 30 (bone surface). (authors)

  17. Safeguards considerations for uranium enrichment facilities, as applied to gas centrifuge and gaseous diffusion facilities

    International Nuclear Information System (INIS)

    1979-03-01

    The goals and objectives of IAEA safeguards as they are understood by the authors based on published documents are reviewed. These goals are then used to derive safeguards concerns, diversion strategies, and potential safeguards measures for four base cases, the production of highly enriched uranium (HEU) at a diffusion plant, the diversion of low enriched uranium (LEU) at a diffusion plant, the diversion of HEU at a gas centrifuge plant, and the diversion of LEU at a gas centrifuge plant. Tables of estimated capabilities are given for each case, under the assumption that the inspector would have access: to the cascade perimeter at or after the start of operations, to the cascade perimeter throughout construction and operation, to the cascade perimeter during operation plus a one-time access to the cascade itself, to the cascade during construction but only its perimeter during operation, or to the cascade itself during construction and operation

  18. Partnering efforts at the Paducah Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Warren, C.B.

    1995-01-01

    Before individuals or agencies can effectively work together to solve common problems, they must first agree on exactly what those problems are and establish common goals and methods that will lead to mutually acceptable solutions. Then, they must make a conscientious effort to form a cohesive team that focuses on the established goals and deemphasize traditional roles, which may in some instances be considered adversarial. This kind of teamwork/partnering process can be more difficult, though not impossible, to achieve in cases where there are traditional (real or imagined) adversarial relationships between the parties, i.e. regulator vs. regulated. The US Department of Energy Site Office (DOE) at Paducah, Kentucky, the Kentucky Department of Environmental Protection (KDEP) and the US Environmental Protection Agency, Region IV (EPA) have made t strides toward teamwork and partnering at DOE's Paducah Gaseous Diffusion Plant. They have accomplished this in a number of ways, which will be discussed in greater detail but first and foremost, the agencies agreed up front that they had mutual goals and interests. These goals are to protect public health and the environment in a cost-effective and timely manner, taking care to make the wisest use of public resources (tax dollars); to evaluate and minimize risks, and to achieve ''Win-Win'' for all parties concerned

  19. Bioavailability study for the Paducah Gaseous Diffusion Plant

    Energy Technology Data Exchange (ETDEWEB)

    Phipps, T.L.; Kszos, L.A.

    1996-08-01

    The overall purpose of this plan is to assess the bioavailability of metals in the continuous and intermittent outfalls. The results may be used to determine alternative metal limits that more appropriately measure the portion of metal present necessary for toxicity to aquatic life. These limits must remain protective of in-stream aquatic life; thus, the highest concentration of metal in the water will be determined concurrently with an assessment of acute or chronic toxicity on laboratory tests. Using the method developed by the Kentucky Division of Water (KDOW), biomonitoring results and chemical data will be used to recommend alternative metal limits for the outfalls of concern. The data will be used to meet the objectives of the study: (1) evaluate the toxicity of continuous outfalls and intermittent outfalls at Paducah Gaseous Diffusion Plant; (2) determine the mean ratio of dissolved to Total Recoverable metal for Cd, Cr, Cu, Pb, Ni, and Zn in the continuous and intermittent outfalls; (3) determine whether the concentration of total recoverable metal discharged causes toxicity to fathead minnows and /or Ceriodaphnia; and (4) determine alternative metal limits for each metal of concern (Cd, Cr, Cu, Pb, Ni, and Zn).

  20. Innovative Decontamination Technology for Use in Gaseous Diffusion Plant Decommissioning

    International Nuclear Information System (INIS)

    Peters, M.J.; Norton, C.J.; Fraikor, G.B.; Potter, G.L.; Chang, K.C.

    2006-01-01

    The results of bench scale tests demonstrated that TechXtract R RadPro TM technology (hereinafter referred to as RadPro R ) can provide 100% coverage of complex mockup gaseous diffusion plant (GDP) equipment and can decontaminate uranium (U) deposits with 98% to 99.99% efficiency. Deployment tests demonstrated RadPro R can be applied as foam, mist/fog, or steam, and fully cover the internal surfaces of complex mockup equipment, including large piping. Decontamination tests demonstrated that two formulations of RadPro R , one with neutron attenuators and one without neutron attenuators, could remove up to 99.99% of uranyl fluoride deposits, one of the most difficult to remove deposits in GDP equipment. These results were supplemented by results from previous tests conducted in 1994 that showed RadPro R could remove >97% of U and Tc-99 contamination from actual GDP components. Operational use of RadPro R at other DOE and commercial facilities also support these data. (authors)

  1. Paducah Gaseous Diffusion Plant Northwest Plume interceptor system evaluation

    International Nuclear Information System (INIS)

    Laase, A.D.; Clausen, J.L.

    1998-01-01

    The Paducah Gaseous Diffusion Plant (PGDP) recently installed an interceptor system consisting of four wells, evenly divided between two well fields, to contain the Northwest Plume. As stated in the Northwest Plume Record of Decision (ROD), groundwater will be pumped at a rate to reduce further contamination and initiate control of the northwest contaminant plume. The objective of this evaluation was to determine the optimum (minimal) well field pumping rates required for plume hotspot containment. Plume hotspot, as defined in the Northwest Plume ROD and throughout this report, is that portion of the plume with trichloroethene (TCE) concentrations greater than 1,000 microg/L. An existing 3-dimensional groundwater model was modified and used to perform capture zone analyses of the north and south interceptor system well fields. Model results suggest that the plume hotspot is not contained at the system design pumping rate of 100 gallons per minute (gal/min) per well field. Rather, the modeling determined that north and south well field pumping rates of 400 and 150 gal/min, respectively, are necessary for plume hotspot containment. The difference between the design and optimal pumping rates required for containment can be attributed to the discovery of a highly transmissive zone in the vicinity of the two well fields

  2. Biodenitrification of gaseous diffusion plant aqueous wastes: stirred bed reactor

    International Nuclear Information System (INIS)

    Holland, M.E.

    1980-01-01

    Approximately 30 kilograms of nitrates per day are discarded in the raffinates (acid wastes) of the Portsmouth Gaseous Diffusion Plant's X-705 Uranium Recovery and Decontamination Facility. A biodenitrification process employing continuous-flow, stirred-bed reactors has been successfully used to remove nitrates from similar acid wastes at the Oak Ridge Y-12 Plant. Laboratory studies have been made at Portsmouth to characterize the X-705 raffinates and to test the stirred-bed biodenitrification process on such raffinates. Raffinates which had been previously characterized were pumped through continuous-flow, stirred-bed, laboratory-scale reactors. Tests were conducted over a period of 146 days and involved variations in composition, mixing requirements, and the fate of several metal ions in the raffinates. Tests results show that 20 weight percent nitrates were reduced to a target nitrate effluent concentration of 100 μg/ml with a 99.64 percent efficiency. However, the average denitrification rate achieved was only 33% of that demonstrated with the Y-12 stirred-bed system. These low rates were probably due to the toxic effects of heavy metal ions on the denitrifying bacteria. Also, most of the uranium in the raffinate feed remained in the biomass and calcite, which collected in the reactor. This could cause criticality problems. For these reasons, it was decided not to make use of the stirred-bed bioreactor at Portsmouth. Instead, the biodenitrification installation now planned will use fluidized bed columns whose performance will be the subject of a subsequent report

  3. Preduction of the vibratory behaviour of a multistage gaseous diffusion plant

    International Nuclear Information System (INIS)

    Descleve, P.; Bertaut, C.; Briot, P.

    1979-01-01

    A study has been made to predict the vibratory behaviour of the rotating machinery of a gaseous diffusion plant starting from the results obtained for a single machine. TRICASTIN gaseous diffusion plant uses several hundred of enrichment stages but only three different sizes of machine are used. Each individual machine is a vertical assembly of a compressor heat exchanger and diffusion barriers, this column is supported on four lugs on a concrete slab. This slab must accomodate thermal expansion and is placed on neoprene pads. Due to the compactness of the system the mass of concrete is relatively small. Typically the mass of a machine of the intermediate size is 84 T, the mass of associated concrete is 55 T. Furthermore this supporting slab is flexible, meaning that a dynamic analysis of the slab shows several frequencies below the compressor rotational speed. Extensive dynamic tests have been conducted on a machine supported on a rigid foundation. These tests have shown that the main source of mechanical excitation was caused at 50 Hz by the unbalance of the electrical motor rotor. Then the problem remained to predict the behaviour of a group of twenty machines in the plant itself. (orig.)

  4. Methodology for assessment of safety risk due to potential accidents in US gaseous diffusion plants

    International Nuclear Information System (INIS)

    Turner, J.H.; O'Kain, D.U.

    1991-01-01

    Gaseous diffusion plants that operate in the United States represent a unique combination of nuclear and chemical hazards. Assessing and controlling the health, safety, and environmental risks that can result from natural phenomena events, process upset conditions, and operator errors require a unique methodology. Such a methodology has been developed for the diffusion plants and is being utilized to assess and control the risk of operating the plants. A summary of the methodology developed to assess the unique safety risks at the US gaseous diffusion plants is presented in this paper

  5. Separation of a multicomponent mixture by gaseous diffusion: modelization of the enrichment in a capillary - application to a pilot cascade

    International Nuclear Information System (INIS)

    Doneddu, F.

    1982-01-01

    Starting from the modelization of gaseous flow in a porous medium (flow in a capillary), we generalize the law of enrichment in an infinite cylindrical capillary, established for an isotropic linear mixture, to a multicomponent mixture. A generalization is given of the notion of separation yields and characteristic pressure classically used for separations of isotropic linear mixtures. We present formulas for diagonalizing the diffusion operator, modelization of a multistage, gaseous diffusion cascade and comparison with the experimental results of a drain cascade (N 2 -SF 6 -UF 6 mixture). [fr

  6. Paducah Gaseous Diffusion Plant Annual Site Environmental Report summary for 1993

    International Nuclear Information System (INIS)

    1994-11-01

    This report contains summaries of the environmental programs at Paducah Gaseous Diffusion Plant, environmental monitoring and the results, and the impact of operations on the environment and the public for 1993. The environmental monitoring program at Paducah includes effluent monitoring and environmental surveillance. Effluent monitoring is measurement of releases as they occur. Contaminants are released through either airborne emissions or liquids discharged from the plant. These releases occur as part of normal site operations, such as cooling water discharged from the uranium enrichment cascade operations or airborne releases from ventilation systems. In the event of system failure, this monitoring provides timely warning so that corrective action can be taken before releases reach an unsafe level. Environmental surveillance tracks the dispersion of materials into the environment after they have been released. This involves the collection of samples from various media, such as water, soil, vegetation, and food crops, and the analysis of these samples for certain radionuclides, chemicals, and metals

  7. Portsmouth Gaseous Diffusion Plant Annual Site Environmental Report summary for 1993

    International Nuclear Information System (INIS)

    1994-11-01

    This report contains summaries of the environmental programs at Paducah Gaseous Diffusion Plant, environmental monitoring and the results, and the impact of operations on the environment and the public for 1993. The environmental monitoring program at Paducah includes effluent monitoring and environmental surveillance. Effluent monitoring is measurement of releases as they occur. Contaminants are released through either airborne emissions or liquids discharged from the plant. These releases occur as part of normal site operations, such as cooling water discharged from the uranium enrichment cascade operations or airborne releases from ventilation systems. In the event of system failure, this monitoring provides timely warning so that corrective action can be taken before releases reach an unsafe level. Environmental surveillance tracks the dispersion of materials into the environment after they have been released. This involves the collection of samples from various media, such as water, soil, vegetation, and food crops, and the analysis of these samples for certain radionuclides, chemicals, and metals

  8. Decommissioning of the gaseous diffusion plant at BNFL Capenhurst

    International Nuclear Information System (INIS)

    Baxter, S.G.; Bradbury, P.

    1992-01-01

    The history of the on-going dismantling and disposal program for the Capenhurst Diffusion Plant is described. Reference is made to the scale of the project and to the special techniques developed, particularly in the areas of size reduction, decontamination and protection of personnel and the environment. When the project is successfully concluded by the end of 1993 over 99% of the materials of construction of the plant will have been recycled to the environment as clean material. (author)

  9. Nitrogen-system safety study: Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    1982-07-01

    The Department of Energy has primary responsibility for the safety of operations at DOE-owned nuclear facilities. The guidelines for the analysis of credible accidents are outlined in DOE Order 5481.1. DOE has requested that existing plant facilities and operations be reviewed for potential safety problems not covered by standard industrial safety procedures. This review is being conducted by investigating individual facilities and documenting the results in Safety Study Reports which will be compiled to form the Existing Plant Final Safety Analysis Report which is scheduled for completion in September, 1984. This Safety Study documents the review of the Plant Nitrogen System facilities and operations and consists of Section 4.0, Facility and Process Description, and Section 5.0, Accident Analysis, of the Final Safety Analysis Report format. The existing nitrogen system consists of a Superior Air Products Company Type D Nitrogen Plant, nitrogen storage facilities, vaporization facilities and a distribution system. The system is designed to generate and distribute nitrogen gas used in the cascade for seal feed, buffer systems, and for servicing equipment when exceptionally low dew points are required. Gaseous nitrogen is also distributed to various process auxiliary buildings. The average usage is approximately 130,000 standard cubic feet per day

  10. On-line vibration and analysis system at the Paducah Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Herricks, D.M.; Strunk, W.D.

    1987-11-01

    The enrichment facility in Paducah, KY uses a unique hard-wired vibration monitoring and analysis system for gaseous diffusion equipment. The axial flow and centrifugal flow compressors used in uranium enrichment range in size from 6 feet in diameter to less than one foot in diameter. These compressors must operate smoothly and safely, without breech of containment, since the working fluid of gaseous diffusion is gaseous UF 6 . The condition of 1925 compressors is monitored by use of the 2500 point vibration analysis system. Since the failure mechanisms of the compressors are well known and documented, only one accelerometer per machine is needed for most machines. The system is completely automated and can generate spectra or broadband levels in either acceleration or velocity units. Levels are stored for historical review. The analyst can, via a custom telecommunications link, view and analyze data from all monitored points with an office PC. 4 figs

  11. Validation of KENO V.a for the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Felsher, H.D.; Fentiman, A.W.; Tayloe, R.W.; D'Aquila, D.

    1992-01-01

    At the Portsmouth Gaseous Diffusion Plant, KENO V.a is used to make criticality calculations for complex configurations and a wide range of 235 U enrichments. It is essential that the calculated critical conditions either accurately reflect the true critical state or that the bias from the true critical conditions are well known. Accordingly, a study has been initiated to validate KENO V.a over the ranges of parameters expected to be used when modeling equipment and processes at Portsmouth. Preliminary results of that study are reported in this paper. The ultimate goal of this study is to identify a set of data from existing critical experiments that will exercise all KENO V.a parameters commonly used by Portsmouth's criticality safety personnel. A second goal is to identify a relatively small subset of those experiments that may be run frequently to ensure that KENO V.a provides consistent results

  12. Handling of UF6 in U.S. gaseous diffusion plants

    International Nuclear Information System (INIS)

    Legeay, A.J.

    1978-01-01

    A comprehensive systems analysis of UF 6 handling has been made in the three U.S. gaseous diffusion plants and has resulted in a significant impact on the equipment design and the operating procedures of these facilities. The equipment, facilities, and industrial practices in UF 6 handling operations as they existed in the early 1970's are reviewed with particular emphasis placed on the changes which have been implemented. The changes were applied to the systems and operating methods which evolved from the design, startup, and operation of the Oak Ridge Gaseous Diffusion Plant in 1945

  13. Preliminary study of PCBs in raccoons living on or near the Paducah Gaseous Diffusion Plant, Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    Halbrook, Richard S. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Zoology. Cooperative Wildlife Research Lab. Kentucky Research Consortium for Energy and Environment

    2016-01-15

    The “Ecological Monitoring at the Paducah Gaseous Diffusion Plant: Historical Evaluation and Guidelines for Future Monitoring” report (Halbrook, et al. 2007) recommended the raccoon as a species for study at the Paducah Gaseous Diffusion Plant (PGDP). This species was selected to fill data gaps in ecological resources and provide resource managers with knowledge that will be valuable in making decisions and implementing specific actions to safeguard ecological resources and reduce human exposure. The current paper reports results of a preliminary evaluation to establish protocols for collection of tissues and initial screening of polychlorinated biphenyls (PCBs) in raccoons collected near the PGDP. These data are useful in developing future more comprehensive studies.

  14. Characterization of process holdup material at the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Boyd, D.E.; Miller, R.R.

    1986-01-01

    The cascade material balance area at the Portsmouth Gaseous Diffusion Plant is characterized by continuous, large, in-process inventories of gaseous uranium hexafluoride (UF 6 ) and very large inputs and outputs of UF 6 over a complete range of 235 U enrichments. Monthly inventories are conducted to quantify the in-place material, but the inventory techniques are blind to material not in the gas phase. Material is removed from the gas phase by any one of four mechanisms: (1) freeze-outs which are the solidification of UF 6 , (2) inleakage of wet air which produces solid uranium oxyfluorides, (3) consumption of uranium through UF 6 reaction with internal metal surfaces, and (4) adsorption of UF 6 on internal surfaces. This presentation describes efforts to better characterize and, where possible, to eliminate or reduce the effects of these mechanisms on material accountability. Freeze-outs and wet air deposits occur under absormal operating conditions, and techniques are available to prevent, detect and reverse them. Consumption and adsorption occur under normal operating conditions and are more complex to manage, however, computer models have been developed to quantify monthly the net effects due to consumption and adsorption. These models have shown that consumption and adsorption effects on inventory differences are significant

  15. Development of NF3 Deposit Removal Technology for the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Scheele, R.D.; McNamara, B.K.; Rapko, B.M.; Edwards, M.K.; Kozelisky, A.E.; Daniel, R.C.; McSweeney, T.I.; Maharas, S.J.; Weaver, P.J.; Iwamasa, K.J.; Kefgen, R.B.

    2006-01-01

    This paper summarizes the Battelle, Stoller, and WASTREN (BSW) team's efforts, to date, in support of the United States Department of Energy's plans to remove uranium and technetium deposits before decommissioning the Portsmouth Gaseous Diffusion Plant. The BSW team investigated nitrogen trifluoride (NF 3 ) as a safer yet effective alternative gaseous treatment to the chlorine trifluoride (ClF 3 )-elemental fluorine (F 2 ) treatment currently used to remove uranium and technetium deposits from the uranium enrichment cascade. Both ClF 3 and F 2 are highly reactive, toxic, and hazardous gases, while NF 3 , although toxic [1], is no more harmful than moth balls [2]. BSW's laboratory thermo-analytical and laboratory-scale prototype studies with NF 3 established that thermal NF 3 can effectively remove likely and potential uranium (UO 2 F 2 and UF 4 ) and technetium deposits (a surrogate deposit material, TcO 2 , and pertechnetates) by conversion to volatile compounds. Our engineering evaluations suggest that NF 3 's effectiveness could be enhanced by combining with a lesser concentration of ClF 3 . BSW's and other's studies indicate compatibility with Portsmouth materials of construction (aluminum, copper, and nickel). (authors)

  16. An aerial radiological survey of the Portsmouth Gaseous Diffusion Plant and surrounding area, Portsmouth, Ohio

    International Nuclear Information System (INIS)

    1992-09-01

    An aerial radiological survey was conducted from July 11--20, 1990, over an 83-square-kilometer (32-square-mile) area surrounding the Portsmouth Gaseous Diffusion Plant located near Portsmouth, Ohio. The survey was conducted at a nominal altitude of 91 meters (300 feet) with line spacings of 122 meters (400 feet). A contour map of the terrestrial gamma exposure rate extrapolated to 1 meter above ground level (AGL) was prepared and overlaid on an aerial photograph and a set of United States Geological Survey (USGS) topographic maps of the area. The terrestrial exposure rates varied from about 7 to 14 microroentgens per hour (μR/h) at 1 meter above the ground. Analysis of the data for man-made sources and for the uranium decay product, protactinium-234m ( 234m Pa), showed five sites within the boundaries of the Portsmouth Gaseous Diffusion Plant with elevated readings. Spectra obtained in the vicinity of the buildings at the Portsmouth Gaseous Diffusion Plant showed the presence of 234m Pa, a uranium-238 ( 238 U) decay product. In addition, spectral analysis of the data obtained over the processing plant facility showed gamma activity indicative of uranium-235 ( 234 U). No other man-made gamma ray emitting radioactive material was detected, either on or off the Portsmouth Gaseous Diffusion Plant property. Soil samples and pressurized ion chamber measurements were obtained at five different locations within the survey boundlaries to support the aerial data

  17. Environmental Restoration Site-Specific Plan for the Portsmouth Gaseous Diffusion Plant, FY 93

    International Nuclear Information System (INIS)

    1993-01-01

    The purpose of this Site-Specific Plan (SSP) is to describe past, present, and future activities undertaken to implement Environmental Restoration and Waste Management goals at the Portsmouth Gaseous Diffusion Plant (PORTS). The SSP is presented in sections emphasizing Environmental Restoration description of activities, resources, and milestones

  18. Real Time Demonstration Project XRF Performance Evaluation Report for Paducah Gaseous Diffusion Plant AOC 492

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Robert L [Argonne National Laboratory

    2008-04-03

    This activity was undertaken to demonstrate the applicability of market-available XRF instruments to quantify metal concentrations relative to background and risk-based action and no action levels in Paducah Gaseous Diffusion Plant (PGDP) soils. As such, the analysis below demonstrates the capabilities of the instruments relative to soil characterization applications at the PGDP.

  19. Lung Cancer Mortality among Uranium Gaseous Diffusion Plant Workers: A Cohort Study 1952–2004

    Directory of Open Access Journals (Sweden)

    LW Figgs

    2013-07-01

    Full Text Available Background: 9%–15% of all lung cancers are attributable to occupational exposures. Reports are disparate regarding elevated lung cancer mortality risk among workers employed at uranium gaseous diffusion plants. Objective: To investigate whether external radiation exposure is associated with lung cancer mortality risk among uranium gaseous diffusion workers. Methods: A cohort of 6820 nuclear industry workers employed from 1952 to 2003 at the Paducah uranium gaseous diffusion plant (PGDP was assembled. A job-specific exposure matrix (JEM was used to determine likely toxic metal exposure categories. In addition, radiation film badge dosimeters were used to monitor cumulative external ionizing radiation exposure. International Classification for Disease (ICD codes 9 and 10 were used to identify 147 lung cancer deaths. Logistic and proportional hazards regression were used to estimate lung cancer mortality risk. Results: Lung cancer mortality risk was elevated among workers who experienced external radiation >3.5 mrem and employment duration >12 years. Conclusion: Employees of uranium gaseous diffusion plants carry a higher risk of lung cancer mortality; the mortality is associated with increased radiation exposure and duration of employment.

  20. Environmental program audit: Oak Ridge Gaseous Diffusion Plant, Roane County, Tennessee. Final report

    International Nuclear Information System (INIS)

    Smith, W.M.; Waller, R.

    1985-01-01

    An environmental audit of the Oak Ridge Gaseous Diffusion Plant (ORGDP) was conducted by a team of NUS scientists and engineers during the week of June 3 through June 7, 1985. ORGDP is owned by the Department of Energy and operated by Martin-Marietta Energy Systems, Inc. To enrich uranium feedstocks for nuclear fuels. The team evaluated ORGDP in terms of compliance with environmental regulations and DOE Orders, the adequacy of pollution control equipment, the effectiveness of environmental monitoring, and the application of quality control procedures to environmental programs. The audit was conducted by observing operations, inspecting facilities, evaluating analysis and monitoring techniques, reviewing reports and data, and interviewing personnel. Overall, the ORGDP environmental program appears to be well structured and has attempted to address all areas of air, water, and land media likely to be affected by the operations of the facility. The plant management is knowledgeable about environmental concerns and has established clear, well-defined goals to address these areas. An adequate professional staff is available to manage the environmental program

  1. Long-range global warming impact of gaseous diffusion plant operation

    International Nuclear Information System (INIS)

    Trowbridge, L.D.

    1992-09-01

    The DOE gaseous diffusion plant complex makes extensive use of CFC-114 as a primary coolant. As this material is on the Montreal Protocol list of materials scheduled for production curtailment, a substitute must be found. In addition to physical cooling properties, the gaseous diffusion application imposes the unique requirement of chemical inertness to fluorinating agents. This has narrowed the selection of a near-term substitute to two fully fluorinated material, FC-318 and FC-3110, which are likely to be strong, long-lived greenhouse gases. In this document, calculations are presented showing, for a number of plausible scenarios of diffusion plant operation and coolant replacement strategy, the future course of coolant use, greenhouse gas emissions (including coolant and power-related indirect CO 2 emissions), and the consequent global temperature impacts of these scenarios

  2. 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

  3. Unattended Monitoring of HEU Production in Gaseous Centrifuge Enrichment Plants using Automated Aerosol Collection and Laser-based Enrichment Assay

    International Nuclear Information System (INIS)

    Anheier, Norman C.; Bushaw, Bruce A.

    2010-01-01

    Nuclear power is enjoying rapid growth as government energy policies and public demand shift toward low carbon energy production. Pivotal to the global nuclear power renaissance is the development and deployment of robust safeguards instrumentation that allows the limited resources of the IAEA to keep pace with the expansion of the nuclear fuel cycle. Undeclared production of highly enriched uranium (HEU) remains a primary proliferation concern for modern gaseous centrifuge enrichment plants (GCEPs), due to their massive separative work unit (SWU) processing power and comparably short cascade equilibrium timescale. The Pacific Northwest National Laboratory is developing an unattended safeguards instrument, combining continuous aerosol particulate collection with uranium isotope assay, to provide timely detection of HEU production within a GCEP. This approach is based on laser vaporization of aerosol particulates, followed by laser spectroscopy to characterize the uranium enrichment level. Our prior investigation demonstrated single-shot detection sensitivity approaching the femtogram range and relative isotope ratio uncertainty better than 10% using gadolinium as a surrogate for uranium. In this paper we present measurement results on standard samples containing traces of depleted, natural, and low enriched uranium, as well as measurements on aerodynamic size uranium particles mixed in background materials (e.g., dust, minerals, soils). Improvements and optimizations in the detection electronics, signal timing, calibration, and laser alignment have lead to significant improvements in detection sensitivity and enrichment accuracy, contributing to an overall reduction in the false alarm probability. The sample substrate media was also found to play a significant role in facilitating laser-induced vaporization and the production of energetic plasma conditions, resulting in ablation optimization and further improvements in the isotope abundance sensitivity.

  4. Recovery of energy in a gaseous diffusion plant

    International Nuclear Information System (INIS)

    Ergalant, Jacques; Guais, J.-C.; Perrault, Michel; Vignet, Paul

    1975-01-01

    Any energy recovery, even partial, goes in the direction of savings in energy and should be sought for. The Tricastin plant, now in the course of being built, will be able to deliver several hundreds of MW for the purpose of urban and agricultural heating. The new Coredif project will more completely integrate the valorization of calories in its definition (choice of temperatures, design of the heat exchangers, recovery cycles). In fact the recent evolution in energy costs renders the otpimization of a plant equipped with a heat recovery system (1 to 2% on the cost of the uranium produced) now economically worth-while. In the same way, the choice of the site of the future plant may be conditioned by the possible uses of calories in its vicinity [fr

  5. Uranium hexafluoride packaging tiedown systems overview at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    International Nuclear Information System (INIS)

    Becker, D.L.; Green, D.J.; Lindquist, M.R.

    1993-07-01

    The Portsmouth Gaseous Diffusion Plant (PORTS) in Piketon, Ohio, is operated by Martin Marietta Energy Systems, Inc., through the US Department of Energy-Oak Ridge Operations Office (DOE-ORO) for the US Department of Energy-Headquarters, Office of Nuclear Energy. The PORTS conducts those operations that are necessary for the production, packaging, and shipment of uranium hexafluoride (UF 6 ). Uranium hexafluoride enriched uranium than 1.0 wt percent 235 U shall be packaged in accordance with the US Department of Transportation (DOT) regulations of Title 49 CFR Parts 173 (Reference 1) and 178 (Reference 2), or in US Nuclear Regulatory Commission (NRC) or US Department of Energy (DOE) certified package designs. Concerns have been expressed regarding the various tiedown methods and condition of the trailers being used by some shippers/carriers for international transport of the UF 6 cylinders/overpacks. Because of the concerns about international shipments, the US Department of Energy-Headquarters (DOE-HQ) Office of Nuclear Energy, through DOE-HQ Transportation Management Division, requested Westinghouse Hanford Company (Westinghouse Hanford) to review UF 6 packaging tiedown and shipping practices used by PORTS, and where possible and appropriate, provide recommendations for enhancing these practices. Consequently, a team of two individuals from Westinghouse Hanford visited PORTS on March 5 and 6, 1990, for the purpose of conducting this review. The paper provides a brief discussion of the review activities and a summary of the resulting findings and recommendations. A detailed reporting of the is documented in Reference 4

  6. Replacement of chlorofluorocarbons at the DOE gaseous diffusion plants: An assessment of global impacts

    International Nuclear Information System (INIS)

    Socolof, M.L.; McCold, L.N.; Saylor, R.E.

    1997-01-01

    Three gaseous diffusion plants (GDPs) for enriching uranium maintain a large inventory of chlorofluorocarbon-114 (CFC-114) as a coolant. To address the continued use of CFC-114, an ozone-depleting substance, the US Department of Energy (DOE) considered introducing perfluorocarbons (PFCs) by the end of 1995. These PFCs would not contribute to stratospheric ozone depletion but would be larger contributors to global warming than would CFC-114. The paper reports the results of an assessment of the global impacts of four alternatives for modifying GDP coolant system operations over a three-year period beginning in 1996. The overall contribution of GDP coolant releases to impacts on ozone depletion and global warming were quantified by parameters referred to as ozone-depletion impact and global-warming impact. The analysis showed that these parameters could be used as surrogates for predicting global impacts to all resources and could provide a framework for assessing environmental impacts of a permanent coolant replacement, eliminating the need for subsequent resource-specific analyses

  7. Uranium isotope separation by gaseous diffusion and plant safety

    International Nuclear Information System (INIS)

    Simeon, Claude; Dumas, Maurice.

    1980-07-01

    This report constitutes a safety guide for operators of uranium isotope separation plants, and includes both aspects of safety and protection. Taking into account the complexity of safety problems raised at design and during operation of plants which require specialized guides, this report mainly considers both the protection of man, the environment and goods, and the principles of occupational safety. It does not claim to be comprehensive, but intends to state the general principles, the particular points related to the characteristics of the basic materials and processes, and to set forth a number of typical solutions suitable for various human and technical environments. It is based on the French experience gained during the last fifteen years [fr

  8. Portsmouth gaseous diffusion plant environmental monitoring report for calendar year 1975

    International Nuclear Information System (INIS)

    Martin, W.E.; Netzer, W.D.

    1976-01-01

    At the Portsmouth Gaseous Diffusion Plant the ambient atmosphere and all effluent streams are sampled and analyzed regularly for conformance to applicable environmental standards. Although neither the State of Ohio nor the federal government has established standards for fluorides in the ambient atmosphere or in vegetation, these parameters also are monitored because fluoride compounds are used extensively in the gaseous diffusion process. Radioactivity is measured in air, water, food, soil, and sediments; and radiation doses are calculated for the public. All public radiation doses are well within federal standards. Non-radioactive effluent parameters either comply with federal standards, or there are projects planned to allow compliance. A disposal facility to remove chromium from recirculating cooling water blowdown will begin operation in June 1976. Also, pH adjustment facilities for liquid effluents and electrostatic precipitators for a coal-fired steam plant are planned for the near future

  9. Detector for flow abnormalities in gaseous diffusion plant compressors

    Science.gov (United States)

    Smith, S.F.; Castleberry, K.N.

    1998-06-16

    A detector detects a flow abnormality in a plant compressor which outputs a motor current signal. The detector includes a demodulator/lowpass filter demodulating and filtering the motor current signal producing a demodulated signal, and first, second, third and fourth bandpass filters connected to the demodulator/lowpass filter, and filtering the demodulated signal in accordance with first, second, third and fourth bandpass frequencies generating first, second, third and fourth filtered signals having first, second, third and fourth amplitudes. The detector also includes first, second, third and fourth amplitude detectors connected to the first, second, third and fourth bandpass filters respectively, and detecting the first, second, third and fourth amplitudes, and first and second adders connected to the first and fourth amplitude detectors and the second and third amplitude detectors respectively, and adding the first and fourth amplitudes and the second and third amplitudes respectively generating first and second added signals. Finally, the detector includes a comparator, connected to the first and second adders, and comparing the first and second added signals and detecting the abnormal condition in the plant compressor when the second added signal exceeds the first added signal by a predetermined value. 6 figs.

  10. Introduction to the nuclear criticality safety evaluation of facility X-705, Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Sheaffer, M.K.; Keeton, S.C.

    1993-01-01

    This report is the first in a series of documents that will evaluate nuclear criticality safety in the Decontamination and Recovery Facility, X-705, Portsmouth Gaseous Diffusion Plant. It provides an overview of the facility, categorizes its functions for future analysis, reviews existing NCS documentation, and explains the follow-on effort planned for X-705. A detailed breakdown of systems, subsystems, and operational areas is presented and cross-referenced to existing NCS documentation

  11. The new local control systems for operating gaseous diffusion plant units at Pierrelatte

    International Nuclear Information System (INIS)

    Delacroix, C.

    1990-01-01

    The development of a local control network for operating gaseous diffusion plant units is presented. The objective of the control system up date was to replace all the information network hardware. The new generation HP1000 calculators and a network architecture were chosen. The validation tests performed in laboratory and in situ, and the management policies towards the personnel during the technical changes are summarized [fr

  12. Environmental Restoration Site-Specific Plan for the Paducah Gaseous Diffusion Plant, FY 93

    International Nuclear Information System (INIS)

    1993-01-01

    This report provides an overview of the major Environmental Restoration (ER) concerns at Paducah Gaseous Diffusion Plant (PGDP). The identified solid waste management units at PGDP are listed. In the Department of Energy (DOE) Five Year Plan development process, one or more waste management units are addressed in a series of activity data sheets (ADSs) which identify planned scope, schedule, and cost objectives that are representative of the current state of planned technical development for individual or multiple sites

  13. Nuclear criticality safety evaluation of Spray Booth Operations in X-705, Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Sheaffer, M.K.; Keeton, S.C.

    1993-01-01

    This report evaluates nuclear criticality safety for Spray Booth Operations in the Decontamination and Recovery Facility, X-705, at the Portsmouth Gaseous Diffusion Plant. A general description of current procedures and related hardware/equipment is presented. Control parameters relevant to nuclear criticality safety are explained, and a consolidated listing of administrative controls and safety systems is developed. Based on compliance with DOE Orders and MMES practices, the overall operation is evaluated, and recommendations for enhanced safety are suggested

  14. Uranium hexafluoride packaging tiedown systems overview at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    International Nuclear Information System (INIS)

    Becker, D.L.; Lindquist, M.R.

    1993-01-01

    The Portsmouth Gaseous Diffusion Plant (PORTS) in Piketon, Ohio, is operated by Martin Marietta Energy Systems, Inc., through the US Department of Energy-Oak Ridge Operations Office (DOE-ORO) for the US Department of Energy-Headquarters, Office of Nuclear Energy. The PORTS conducts those operations that are necessary for the production, packaging, and shipment of enriched uranium hexafluoride (UF 6 ). Uranium hexafluoride enriched greater than 1.0 wt percent 235 U shall be packaged in accordance with the US Department of Transportation (DOT) regulations of Title 49 CFR Parts 173 and 178, or in US Nuclear Regulatory Commission (NRC) or US Department of Energy (DOE) certified package designs. Concerns have been expressed regarding the various tiedown methods and condition of the trailers being used by some shippers/carriers for international transport of the UF 6 cylinders/overpacks. International shipments typically are not made using dedicated trailers, and numerous trailers have been received at PORTS with improperly and potentially dangerously secured overpacks. Because of the concerns about international shipments, the US Department of Energy-Headquarters (DOE-HQ) Office of Nuclear Energy, through DOE-HQ Transportation Management Division, requested Westinghouse Hanford Company (Westinghouse Hanford) to review UF 6 packaging tiedown and shipping practices used by PORTS; and where possible and appropriate, provide recommendations for enhancing these practices. Consequently, a team of two individuals from Westinghouse Hanford visited PORTS on March 5 and 6, 1990, for the purpose of conducting this review. The paper provides a brief discussion of the review activities and a summary of the resulting findings and recommendations

  15. Cooling tower drift studies at the Paducah, Kentucky Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Taylor, F.G.; Hanna, S.R.; Parr, P.D.

    1979-01-01

    The transfer and fate of chromium from cooling tower drift to terrestrial ecosystems were quantified at the Department of Energy's uranium enrichment facility at Paducah, Kentucky. Chromium concentrations in plant materials (fescue grass) decreased with increasing distance from the cooing tower, ranging from 251 +- 19 ppM at 15 meters to 0.52 +- 0.07 ppM at 1500 meters. The site of drift contamination, size characteristics, and elemental content of drift particles were determined using a scanning electron microscope with energy dispersive x-ray analysis capabilities. Results indicate that elemental content in drift water (mineral residue) may not be equivalent to the content in the recirculating cooling water of the tower. This hypothesis is contrary to basic assumptions in calculating drift emissions. A laboratory study simulating throughfall from 1 to 6 inches of rain suggested that there are more exchange sites associated with litter than live foliage. Leachate from each one inch throughfall simulant removed 3% of the drift mass from litter compared to 7 to 9% from live foliage. Results suggest that differences in retention are related to chemical properties of the drift rather than physical lodging of the particle residue. To determine the potential for movement of drift-derived chromium to surface streams, soil--water samplers (wells) were placed along a distance gradient to Little Bayou Creek. Samples from two depths following rainstorms revealed the absence of vertical or horizontal movement with maximum concentrations of 0.13 ppb at 50 meters from the tower. Preliminary model estimates of drift deposition are compared to depositionmeasurements. Isopleths of the predicted deposition are useful to identify areas of maximum drift transport in the environs of the gaseous diffusion plant

  16. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Portsmouth Gaseous Diffusion Plant site

    International Nuclear Information System (INIS)

    Marmer, G.J.; Dunn, C.P.; Filley, T.H.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Cleland, J.H.

    1991-09-01

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. In the 1970s, the US Department of Energy (DOE) began investigating more efficient and cost-effective enrichment technologies. In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser isotope Separation (U-AVLIS) technology with the near-term goal to provide the necessary information to make a deployment decision by November 1992. Initial facility operation is anticipated for 1999. A programmatic document for use in screening DOE sites to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. The final evaluation, which included sensitivity studies, identified the Oak Ridge Gaseous Diffusion Plant (ORGDP) site, the Paducah Gaseous Diffusion Plant (PGDP) site, and the Portsmouth Gaseous Diffusion Plant (PORTS) site as having significant advantages over the other sites considered. This environmental site description (ESD) provides a detailed description of the PORTS site and vicinity suitable for use in an environmental impact statement (EIS). This report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during site visits. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use. Socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3

  17. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Portsmouth Gaseous Diffusion Plant site

    Energy Technology Data Exchange (ETDEWEB)

    Marmer, G.J.; Dunn, C.P.; Filley, T.H.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Cleland, J.H.

    1991-09-01

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. In the 1970s, the US Department of Energy (DOE) began investigating more efficient and cost-effective enrichment technologies. In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser isotope Separation (U-AVLIS) technology with the near-term goal to provide the necessary information to make a deployment decision by November 1992. Initial facility operation is anticipated for 1999. A programmatic document for use in screening DOE sites to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. The final evaluation, which included sensitivity studies, identified the Oak Ridge Gaseous Diffusion Plant (ORGDP) site, the Paducah Gaseous Diffusion Plant (PGDP) site, and the Portsmouth Gaseous Diffusion Plant (PORTS) site as having significant advantages over the other sites considered. This environmental site description (ESD) provides a detailed description of the PORTS site and vicinity suitable for use in an environmental impact statement (EIS). This report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during site visits. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use. Socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3.

  18. The Mailbox Computer System for the IAEA verification experiment on HEU downblending at the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Aronson, A.L.; Gordon, D.M.

    2000-01-01

    IN APRIL 1996, THE UNITED STATES (US) ADDED THE PORTSMOUTH GASEOUS DIFFUSION PLANT TO THE LIST OF FACILITIES ELIGIBLE FOR THE APPLICATION OF INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA) SAFEGUARDS. AT THAT TIME, THE US PROPOSED THAT THE IAEA CARRY OUT A ''VERIFICATION EXPERIMENT'' AT THE PLANT WITH RESPECT TO DOOWNBLENDING OF ABOUT 13 METRIC TONS OF HIGHLY ENRICHED URANIUM (HEU) IN THE FORM OF URANIUM HEXAFLUROIDE (UF6). DURING THE PERIOD DECEMBER 1997 THROUGH JULY 1998, THE IAEA CARRIED OUT THE REQUESTED VERIFICATION EXPERIMENT. THE VERIFICATION APPROACH USED FOR THIS EXPERIMENT INCLUDED, AMONG OTHER MEASURES, THE ENTRY OF PROCESS-OPERATIONAL DATA BY THE FACILITY OPERATOR ON A NEAR-REAL-TIME BASIS INTO A ''MAILBOX'' COMPUTER LOCATED WITHIN A TAMPER-INDICATING ENCLOSURE SEALED BY THE IAEA

  19. Construction and operation of an industrial solid waste landfill at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    The US Department of Energy (DOE), Office of Waste Management, proposes to construct and operate a solid waste landfill within the boundary of the Portsmouth Gaseous Diffusion Plant (PORTS), Piketon, Ohio. The purpose of the proposed action is to provide PORTS with additional landfill capacity for non-hazardous and asbestos wastes. The proposed action is needed to support continued operation of PORTS, which generates non-hazardous wastes on a daily basis and asbestos wastes intermittently. Three alternatives are evaluated in this environmental assessment (EA): the proposed action (construction and operation of the X-737 landfill), no-action, and offsite shipment of industrial solid wastes for disposal.

  20. Cleanup operations at the Oak Ridge Gaseous Diffusion Plant contaminated metal scrapyard

    International Nuclear Information System (INIS)

    Williams, L.C.

    1987-01-01

    Cleanup operations at the contaminated metal storage yard located at the Oak Ridge, Tennessee, Gaseous Diffusion Plant have been completed. The storage yard, in existence since the early 1970s, contained an estimated 35,000 tons of mixed-type metals spread over an area of roughly 30 acres. The overall cleanup program required removing the metal from the storage yard, sorting by specific metal types, and size reduction of specific types for future processing. This paper explains the methods and procedures used to accomplish this task

  1. Study of technetium uptake in vegetation in the vicinity of the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Acox, T.A.

    1982-01-01

    Technetium-99 was measured in vegetation and soil collected on and near the Portsmouth Gaseous Diffusion Plant to obtain an estimate of the soil-to-vegetation concentration factors. The concentration factors appear to be lognormally distributed with a geometric mean of 3.4 (Bq/kg dry wt. tissue per Bq/kg dry wt. soil) and a geometric standard deviation of 4.7. A dose commitment was calculated using a hypothetical 3.7 x 10 10 Bq Tc-99/year release and the actual CY-1981 concentration release of Tc-99. The radiological significance of Tc-99 in the terrestial food chain is substantially less than previously believed

  2. Nuclear criticality safety evaluation of large cylinder cleaning operations in X-705, Portsmouth Gaseous diffusion Plant

    International Nuclear Information System (INIS)

    Sheaffer, M.K.; Keeton, S.C.; Lutz, H.F.

    1995-06-01

    This report evaluates nuclear criticality safety for large cylinder cleaning operations in the Decontamination and Recovery Facility, X-705, at the Portsmouth Gaseous Diffusion Plant. A general description of current cleaning procedures and required hardware/equipment is presented, and documentation for large cylinder cleaning operations is identified and described. Control parameters, design features, administrative controls, and safety systems relevant to nuclear criticality are discussed individually, followed by an overall assessment based on the Double Contingency Principle. Recommendations for enhanced safety are suggested, and issues for increased efficiency are presented

  3. Construction and operation of an industrial solid waste landfill at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    International Nuclear Information System (INIS)

    1995-10-01

    The US Department of Energy (DOE), Office of Waste Management, proposes to construct and operate a solid waste landfill within the boundary of the Portsmouth Gaseous Diffusion Plant (PORTS), Piketon, Ohio. The purpose of the proposed action is to provide PORTS with additional landfill capacity for non-hazardous and asbestos wastes. The proposed action is needed to support continued operation of PORTS, which generates non-hazardous wastes on a daily basis and asbestos wastes intermittently. Three alternatives are evaluated in this environmental assessment (EA): the proposed action (construction and operation of the X-737 landfill), no-action, and offsite shipment of industrial solid wastes for disposal

  4. Aerial radiological survey of the area surrounding the Portsmouth Gaseous Diffusion Plant, Portsmouth, Ohio

    International Nuclear Information System (INIS)

    1979-09-01

    An airborne radiological survey was conducted in July 1976. It was centered on the Portsmouth Gaseous Diffusion Plant. Two areas were surveyed: one 35 km 2 and the other 16 km 2 . Using Nal(Tl) scintillation detectors, measurements were made of the terrestrial gamma radiation over the areas with a series of north-south flight lines. The processed data indicated that on-site radioactivity was due to nuclear matterials currently or previously handled, processed, or stored. Off-site activities were found to be due wholly to the naturally occurring 40 K, the 238 U chain, and thorium chain gamma emitters

  5. Project plan for the background soils project for the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    The Background Soils Project for the Paducah Gaseous Diffusion Plant (BSPP) will determine the background concentration levels of selected naturally occurring metals, other inorganics, and radionuclides in soils from uncontaminated areas in proximity to the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky. The data will be used for comparison with characterization and compliance data for soils, with significant differences being indicative of contamination. All data collected as part of this project will be in addition to other background databases established for the PGDP. The BSPP will address the variability of surface and near-surface concentration levels with respect to (1) soil taxonomical types (series) and (2) soil sampling depths within a specific soil profile. The BSPP will also address the variability of concentration levels in deeper geologic formations by collecting samples of geologic materials. The BSPP will establish a database, with recommendations on how to use the data for contaminated site assessment, and provide data to estimate the potential human and health and ecological risk associated with background level concentrations of potentially hazardous constituents. BSPP data will be used or applied as follows.

  6. Project plan for the background soils project for the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    International Nuclear Information System (INIS)

    1995-09-01

    The Background Soils Project for the Paducah Gaseous Diffusion Plant (BSPP) will determine the background concentration levels of selected naturally occurring metals, other inorganics, and radionuclides in soils from uncontaminated areas in proximity to the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky. The data will be used for comparison with characterization and compliance data for soils, with significant differences being indicative of contamination. All data collected as part of this project will be in addition to other background databases established for the PGDP. The BSPP will address the variability of surface and near-surface concentration levels with respect to (1) soil taxonomical types (series) and (2) soil sampling depths within a specific soil profile. The BSPP will also address the variability of concentration levels in deeper geologic formations by collecting samples of geologic materials. The BSPP will establish a database, with recommendations on how to use the data for contaminated site assessment, and provide data to estimate the potential human and health and ecological risk associated with background level concentrations of potentially hazardous constituents. BSPP data will be used or applied as follows

  7. Detection of illicit HEU production in gaseous centrifuge enrichment plants using neutron counting techniques on product cylinders

    International Nuclear Information System (INIS)

    Freeman, Corey R.; Geist, William H.

    2010-01-01

    Innovative and novel safeguards approaches are needed for nuclear energy to meet global energy needs without the threat of nuclear weapons proliferation. Part of these efforts will include creating verification techniques that can monitor uranium enrichment facilities for illicit production of highly-enriched uranium (HEU). Passive nondestructive assay (NDA) techniques will be critical in preventing illicit HEU production because NDA offers the possibility of continuous and unattended monitoring capabilities with limited impact on facility operations. Gaseous centrifuge enrichment plants (GCEP) are commonly used to produce low-enriched uranium (LEU) for reactor fuel. In a GCEP, gaseous UF 6 spins at high velocities in centrifuges to separate the molecules containing 238 U from those containing the lighter 235 U. Unfortunately, the process for creating LEU is inherently the same as HEU, creating a proliferation concern. Insuring that GCEPs are producing declared enrichments poses many difficult challenges. In a GCEP, large cascade halls operating thousands of centrifuges work together to enrich the uranium which makes effective monitoring of the cascade hall economically prohibitive and invasive to plant operations. However, the enriched uranium exiting the cascade hall fills product cylinders where the UF 6 gas sublimes and condenses for easier storage and transportation. These product cylinders hold large quantities of enriched uranium, offering a strong signal for NDA measurement. Neutrons have a large penetrability through materials making their use advantageous compared to gamma techniques where the signal is easily attenuated. One proposed technique for detecting HEU production in a GCEP is using neutron coincidence counting at the product cylinder take off stations. This paper discusses findings from Monte Carlo N-Particle eXtended (MCNPX) code simulations that examine the feasibility of such a detector.

  8. An introduction to technetium in the gaseous diffusion cascades

    International Nuclear Information System (INIS)

    Simmons, D.W.

    1996-09-01

    The radioisotope technetium-99 ( 99 Tc) was introduced into the gaseous diffusion plants (GDP) as a contaminant in uranium that had been reprocessed from spent nuclear reactor fuel. 99 Tc is a product of the nuclear fission of uranium-235 ( 235 U). The significantly higher emitted radioactivity of 99 Tc generates concern in the enrichment complex and warrants increased attention (1) to the control of all site emissions, (2) to worker exposures and contamination control when process equipment requires disassembly and decontamination, and (3) to product purity when the enriched uranium hexafluoride (UF 6 ) product is marketed to the private sector. A total of 101,268 metric tons of RU (∼96% of the total) was fed at the Paducah Gaseous Diffusion Plant (PGDP) between FY1953 and FY1976. An additional 5600 metric tons of RU from the government reactors were fed at the Oak Ridge Gaseous Diffusion Plant (ORGDP), plus an approximate 500 tons of foreign reactor returns. Only a small amount of RU was fed directly at the Portsmouth Gaseous Diffusion Plant (PORTS). The slightly enriched PGDP product was then fed to either the ORGDP or PORTS cascades for final enrichment. Bailey estimated in 1988 that of the 606 kg of Tc received at PGDP from RU, 121 kg was subsequently re-fed to ORGDP and 85 kg re-fed to PORTS

  9. Decommissioning of the gaseous diffusion plant at BNF plc Capenhurst in the UK

    International Nuclear Information System (INIS)

    Clements, D.W.; Cross, J.R.

    1993-01-01

    Since 1982, a gaseous diffusion plant located at the British Nuclear Fuels plc (BNFL) site at Capenhurst in the United Kingdom, has been undergoing decontamination, decommissioning, and dismantling. By March 1994, the decontamination and decommissioning activities will be complete with 99% of the materials used to construct the plant recycled to the environment as clean material. This paper describes the history of the decontamination, decommissioning, dismantling, and disposal program. Reference is made to the scale of the project and to the special techniques developed, particularly in the areas of size reduction, decontamination, and protection of personnel and the environment. The quantities of material involved that require decontamination and release levels for recycling materials in the U.K. metals market are discussed

  10. A probabilistic safety analysis of UF{sub 6} handling at the Portsmouth Gaseous Diffusion Plant

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, G.J.; Lewis, S.R.; Summitt, R.L. [Safety and Reliability Optimization Services (SAROS), Inc., Knoxville, TN (United States)

    1991-12-31

    A probabilistic safety study of UF{sub 6} handling activities at the Portsmouth Gaseous Diffusion Plant has recently been completed. The analysis provides a unique perspective on the safety of UF{sub 6} handling activities. The estimated release frequencies provide an understanding of current risks, and the examination of individual contributors yields a ranking of important plant features and operations. Aside from the probabilistic results, however, there is an even more important benefit derived from a systematic modeling of all operations. The integrated approach employed in the analysis allows the interrelationships among the equipment and the required operations to be explored in depth. This paper summarizes the methods used in the study and provides an overview of some of the technical insights that were obtained. Specific areas of possible improvement in operations are described.

  11. Portsmouth Gaseous Diffusion Plant environmental monitoring report for calendar year 1981

    International Nuclear Information System (INIS)

    Acox, T.A.; Anderson, R.E.; Hary, L.F.; Klein, L.S.; Vausher, A.L.

    1982-04-01

    At the Portsmouth Gaseous Diffusion Plant all effluent streams are sampled regularly and analyzed to assess compliance with applicable environmental standards. Radioactivity is measured in air, water, food, soil, and sediments; and radiation doses to the public are calculated. All public radiation doses from process effluents are well within Department of Energy and US EPA standards. Non-radioactive effluents either presently comply with federal standards or will comply upon completion of planned projects. The environmental impact of effluents from cleaning and decontamination operations has been reduced through flow reduction and improved chemical treatment. CY-1981 was the first full year under a new National Pollutant Discharge. Elimination System (NPDES) permit for liquid effluents; compliance with the permit's discharge limits did not present any significant problems. Engineering is proceeding on projects to be constructed through 1985 to further reduce the impact of liquid effluents. A new licensed sanitary landfill utilizing the area fill method went into operation in July 1981. Although neither the State of Ohio nor the federal government has established standards for fluoride in the atmosphere or in vegetation, fluorides are monitored because they are used extensively in the gaseous diffusion process

  12. Re-enrichment of depleted uranium by passage through a gaseous diffusion installation; Reenrichissement de l'uranium appauvri par passage dans une installation de diffusion gazeuse

    Energy Technology Data Exchange (ETDEWEB)

    Lagrange, P; Billous, O [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The reader will find in this paper an economic study of the re-utilization of depleted uranium from nuclear reactors, whether its content be above or under natural proportions. Re-utilization is possible either through bringing the depleted product up to its initial content of {sup 235}U by mixture with a richer concentrate, or else by passing it through a gaseous diffusion plant. The economic area of such re-utilization depends on a number of considerations. We give a general study of it, with reference to some typical gaseous diffusion facilities. (author)Fren. [French] Ce rapport examine au point de vue economique la reutilisation de l'uranium appauvri provenant des reacteurs nucleaires, qu'il soit indifferemment en dessus ou en dessous de la teneur naturelle. Cette reutilisation peut se faire soit en ramenant le produit a sa teneur initiale en isotope 235 par un melange convenable avec un concentre plus riche, soit en le faisant passer dans une usine de Diffusion Gazeuse. La zone de rentabilite de cette reutilisation depend de diverses conditions economiques. Elle est etudiee ci-dessous d'une maniere generale, puis en se referant a des installations-type de diffusion gazeuse. (auteur)

  13. OCCUPATIONAL EXPOSURE TO TRICHLOROETHYLENE AND CANCER RISK FOR WORKERS AT THE PADUCAH GASEOUS DIFFUSION PLANT

    Science.gov (United States)

    BAHR, DEBRA E.; ALDRICH, TIMOTHY E.; SEIDU, DAZAR; BRION, GAIL M.; TOLLERUD, DAVID J.; MULDOON, SUSAN; REINHART, NANCY; YOUSEEFAGHA, AHMED; MCKINNEY, PAUL; HUGHES, THERESE; CHAN, CAROLINE; RICE, CAROL; BREWER, DAVID E.; FREYBERG, RONALD W.; MOHLENKAMP, ADRIANE MOSER; HAHN, KRISTEN; HORNUNG, RICHARD; HO, MONA; DASTIDAR, ANIRUDDHA; FREITAS, SAMANTHA; SAMAN, DANIEL; RAVDAL, HEGE; SCUTCHFIELD, DOUGLAS; EGER, KENNETH J.; MINOR, STEVE

    2016-01-01

    Objective The Paducah Gaseous Diffusion Plant (PGDP) became operational in 1952; it is located in the western part of Kentucky. We conducted a mortality study for adverse health effects that workers may have suffered while working at the plant, including exposures to chemicals. Materials and Methods We studied a cohort of 6820 workers at the PGDP for the period 1953 to 2003; there were a total of 1672 deaths to cohort members. Trichloroethylene (TCE) is a specific concern for this workforce; exposure to TCE occurred primarily in departments that clean the process equipment. The Life Table Analysis System (LTAS) program developed by NIOSH was used to calculate the standardized mortality ratios for the worker cohort and standardized rate ratio relative to exposure to TCE (the U.S. population is the referent for age-adjustment). LTAS calculated a significantly low overall SMR for these workers of 0.76 (95% CI: 0.72–0.79). A further review of three major cancers of interest to Kentucky produced significantly low SMR for trachea, bronchus, lung cancer (0.75, 95% CI: 0.72–0.79) and high SMR for Non-Hodgkin's lymphoma (NHL) (1.49, 95% CI: 1.02–2.10). Results No significant SMR was observed for leukemia and no significant SRRs were observed for any disease. Both the leukemia and lung cancer results were examined and determined to reflect regional mortality patterns. However, the Non-Hodgkin's Lymphoma finding suggests a curious amplification when living cases are included with the mortality experience. Conclusions Further examination is recommended of this recurrent finding from all three U.S. Gaseous Diffusion plants. PMID:21468904

  14. Reassessment of liquefaction potential and estimation of earthquake- induced settlements at Paducah Gaseous Diffusion Plant, Paducah, Kentucky. Final report

    International Nuclear Information System (INIS)

    Sykora, D.W.; Yule, D.E.

    1996-04-01

    This report documents a reassessment of liquefaction potential and estimation of earthquake-induced settlements for the U.S. Department of Energy (DOE), Paducah Gaseous Diffusion Plant (PGDP), located southwest of Paducah, KY. The U.S. Army Engineer Waterways Experiment Station (WES) was authorized to conduct this study from FY91 to FY94 by the DOE, Oak Ridge Operations (ORO), Oak Ridge, TN, through Inter- Agency Agreement (IAG) No. DE-AI05-91OR21971. The study was conducted under the Gaseous Diffusion Plant Safety Analysis Report (GDP SAR) Program

  15. Report on the biological monitoring program at Paducah Gaseous Diffusion Plant December 1990 to November 1992

    Energy Technology Data Exchange (ETDEWEB)

    Kszos, L.A. [ed.

    1994-03-01

    On September 23, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). Beginning in fall 1991, the Environmental Sciences Division (ESD) at Oak Ridge National Lab (ORNL) added data collection and report preparation to its responsibilities for the PGDP BMP. The BMP has been continued because it has proven to be extremely valuable in identifying those effluents with the potential for adversely affecting instream fauna, assessing the ecological health of receiving streams, guiding plans for remediation, and protecting human health. In September 1992, a renewed permit was issued which requires toxicity monitoring of continuous and intermittent outfalls on a quarterly basis. The BMP for PGDP consists of three major tasks: (1) effluent and ambient toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities. This report includes ESD/ORNL activities occurring from December 1990 to November 1992.

  16. An in situ survey of the Paducah Gaseous Diffusion Plant and surrounding area

    International Nuclear Information System (INIS)

    Hoover, R.A.

    1994-02-01

    An in situ survey of the area surrounding the Paducah Gaseous Diffusion Plant was conducted between May 17 and 24, 1990. The survey consisted of in situ measurements and of ground sampling. A High Purity Germanium detector was used for the in situ measurements. The ground samples were taken to the, laboratory at EG ampersand G Energy Measurements, Inc., in Santa Barbara, California, for a radionuclide assay on a laboratory system. Results of the in situ measurements found evidence of naturally occurring radioisotopes, cesium-137 from international fallout, and some evidence of anomalous uranium-238. The soil sampling results show only the presence of naturally occurring radioisotopes, cesium-137, and also anomalous uranium-238

  17. Seismically-induced soil amplification at the DOE Paducah Gaseous Diffusion Plant site

    International Nuclear Information System (INIS)

    Sykora, D.W.; Haynes, M.E.

    1991-01-01

    A site-specific earthquake site response (soil amplification) study is being conducted for the Department of Energy (DOE), Paducah Gaseous Diffusion Plant (PGDP). This study is pursuant to an upgraded Final Safety Analysis Report in accordance with requirements specified by DOE. The seismic hazard at PGDP is dominated by the New Madrid Seismic Zone. Site-specific synthetic earthquake records developed by others were applied independently to four soil columns with heights above baserock of about 325 ft. The results for the 1000-year earthquake event indicate that the site period is between 1.0 and 1.5 sec. Incident shear waves are amplified at periods of motion greater than 0.15 sec. The peak free-field horizontal acceleration, occurring at very low periods, is 0.28 g. 13 refs., 13 figs

  18. Seismically-induced soil amplification at the DOE Paducah Gaseous Diffusion Plant Site

    International Nuclear Information System (INIS)

    Sykora, D.W.; Hynes, M.E.; Brock, W.R.; Hunt, R.J.; Shaffer, K.E.

    1991-01-01

    A site-specific earthquake site response (soil amplification) study is being conducted for the Department of Energy (DOE), Paducah Gaseous Diffusion Plant (PGDP). This study is pursuant to an upgraded Final Safety Analysis Report in accordance with requirements specified by DOE. The seismic hazard at PGDP is dominated by the New Madrid Seismic Zone. Site-specific synthetic earthquake records developed by others were applied independently to four soil columns with heights above baserock of about 325 ft. The results for the 1000-year earthquake event indicate that the site period is between 1.0 and 1.5 sec. Incident shear waves are strongly amplified at periods of motion greater than 0.3 sec. The peak free-field horizontal acceleration, occurring at very low periods, is 0.28 g

  19. Local drainage analyses of the Paducah and Portsmouth Gaseous Diffusion Plants during an extreme storm

    International Nuclear Information System (INIS)

    Johnson, R.O.; Wang, J.C.; Lee, D.W.

    1993-01-01

    Local drainage analyses have been performed for the Paducah and Portsmouth Gaseous Diffusion Plants during an extreme storm having an approximate 10,000-yr recurrence interval. This review discusses the methods utilized to accomplish the analyses in accordance with US Department of Energy (DOE) design and evaluation guidelines, and summarizes trends, results, generalizations, and uncertainties applicable to other DOE facilities. Results indicate that some culverts may be undersized, and that the storm sewer system cannot drain the influx of precipitation from the base of buildings. Roofs have not been designed to sustain ponding when the primary drainage system is clogged. Some underground tunnels, building entrances, and ground level air intakes may require waterproofing

  20. Meteorological effects of the mechanical-draft cooling towers of the Oak Ridge Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Hanna, S.R.

    1975-01-01

    The mechanical-draft cooling towers at the Oak Ridge Gaseous Diffusion Plant dissipate about 2000 MW of heat. Downwash occurs about 40 percent of the time, when wind speeds exceed about 3 m/sec. An elevated cloud forms about 10 percent of the time. The length of the visible plume, which is typically 100 or 200 m, is satisfactorily modeled if it is assumed that the plumes from all the cells in a cooling-tower bank combine. The calculation of fog concentration is complicated by the fact that the moisture is not inert but is taking part in the energy exchanges of a thermodynamic system. Calculations of drift deposition agree fairly well with observations

  1. Report on the biological monitoring program at Paducah Gaseous Diffusion Plant December 1990 to November 1992

    International Nuclear Information System (INIS)

    Kszos, L.A.

    1994-03-01

    On September 23, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). Beginning in fall 1991, the Environmental Sciences Division (ESD) at Oak Ridge National Lab (ORNL) added data collection and report preparation to its responsibilities for the PGDP BMP. The BMP has been continued because it has proven to be extremely valuable in identifying those effluents with the potential for adversely affecting instream fauna, assessing the ecological health of receiving streams, guiding plans for remediation, and protecting human health. In September 1992, a renewed permit was issued which requires toxicity monitoring of continuous and intermittent outfalls on a quarterly basis. The BMP for PGDP consists of three major tasks: (1) effluent and ambient toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities. This report includes ESD/ORNL activities occurring from December 1990 to November 1992

  2. Report on the Biological Monitoring Program at Paducah Gaseous Diffusion Plant December 1992--December 1993

    Energy Technology Data Exchange (ETDEWEB)

    Kszos, L.A.; Hinzman, R.L.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.

    1995-06-01

    On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). The goals of BMP are to demonstrate that the effluent limitations established for PGDP protect and maintain the use of Little Bayou and Big Bayou creeks for growth and propagation of fish and other aquatic life, characterize potential health and environmental impacts, document the effects of pollution abatement facilities on stream biota, and recommend any program improvements that would increase effluent treatability. The BMP for PGDP consists of three major tasks: effluent and ambient toxicity monitoring, bioaccumulation studies, and ecological surveys of stream communities (i.e., benthic macroinvertebrates and fish). This report includes ESD activities occurring from December 1992 to December 1993, although activities conducted outside this time period are included as appropriate.

  3. Delisting efforts for mixed radioactive and chemically hazardous waste at the Oak Ridge Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Goodpasture, S.T.

    1987-01-01

    Presently, there are four hazardous wastes at the Oak Ridge Gaseous Diffusion Plant that are candidates for the delisting from the Resource Conservation and Recovery Act (RCRA) hazardous waste regulations. These candidates are the sludges from K-1407-B and C ponds, Central Neutralization Facility sludges, mixed sludges from Y-12 and the ash generated by the RCRA/Toxic Substances Control Act (TSCA) Incinerator. All of these hazardous wastes contain radioactive constituents as well as hazardous constituents. The delisting will be based upon the nonradioactive constituents. Whether the delisting petition is granted or not, the wastes will be handled according to the Department of Energy guidelines for radioactive wastes. The presentation discusses the methodologies for delisting these wastes and the rationale behind the processes

  4. APPLICATION OF THE LASAGNA(trademark) SOIL REMEDIATION TECHNOLOGY AT THE DOE PADUCAH GASEOUS DIFFUSION PLANT

    International Nuclear Information System (INIS)

    Swift, Barry D.; Tarantino, Joseph J. P. E.

    2003-01-01

    The Paducah Gaseous Diffusion Plant (PGDP), owned by the Department of Energy (DOE), has been enriching uranium since the early 1950s. The enrichment process involves electrical and mechanical components that require periodic cleaning. The primary cleaning agent was trichloroethene (TCE) until the late 1980s. Historical documentation indicates that a mixture of TCE and dry ice were used at PGDP for testing the integrity of steel cylinders, which stored depleted uranium. TCE and dry ice were contained in a below-ground pit and used during the integrity testing. TCE seeped from the pit and contaminated the surrounding soil. The Lasagna(trademark) technology was identified in the Record of Decision (ROD) as the selected alternative for remediation of the cylinder testing site. A public-private consortium formed in 1992 (including DOE, the U.S. Environmental Protection Agency, and the Kentucky Department for Environmental Protection, Monsanto, DuPont, and General Electric) developed the Lasagna(trademark) technology. This innovative technology employs electrokinetics to remediate soil contaminated with organics and is especially suited to sites with low permeability soils. This technology uses direct current to move water through the soil faster and more uniformly than hydraulic methods. Electrokinetics moves contaminants in soil pore water through treatment zones comprised of iron filings, where the contaminants are decomposed to basic chemical compounds such as ethane. After three years of development in the laboratory, the consortium field tested the Lasagna(trademark) process in several phases. CDM installed and operated Phase I, the trial installation and field test of a 150-square-foot area selected for a 120-day run in 1995. Approximately 98 percent of the TCE was removed. CDM then installed and operated the next phase (IIa), a year-long test on a 600-square-foot site. Completed in July 1997, this test removed 75 percent of the total volume of TCE down to a

  5. An aerial radiological survey of the Portsmouth Gaseous Diffusion Plant and surrounding area

    International Nuclear Information System (INIS)

    Sampoll-Ramirez, G.

    1994-09-01

    An aerial radiological survey was conducted from August 10-16, 1993, over a 78-square-kilometer (30-square-mile) area of the Portsmouth Gaseous Diffusion Plant and surrounding area located near Portsmouth, Ohio. The survey was performed at a nominal altitude of 46 meters (150 feet) with a line spacing of 76 meters (250 feet). A contour map of the terrestrial gamma exposure rate extrapolated to 1 meter above ground level was prepared and overlaid on a set of United States Geological Survey topographic maps of the area and an aerial photograph of the plant. The terrestrial gamma exposure rates varied from about 7 to 14 microroentgens per hour at 1 meter above the ground. Protactinium-234m was observed at six sites within the boundaries of the plant. At a seventh site, only uranium-235 was observed. No other man-made, gamma ray-emitting radioactive material was present in a detectable quantity, either on or off the plant property. Soil sample and pressurized ion chamber measurements were obtained at four locations within the survey boundaries to support the aerial data. The results of the aerial and ground-based measurements were found to agree within ± 7.5%

  6. Enrichment by diffusion

    International Nuclear Information System (INIS)

    Mezin, M.

    1976-01-01

    The report presents an introduction to general basic principles of the gaseous diffusion process for the separation of uranium isotopes. Dealt with are: a) theoretical background and basic considerations of separation work and production costs, b) construction of a single separation stage and a multistage plant, c) the components of a plant and the optimization factors, d) cost factors. The text is illustrated by instructive diagrammes and flow charts. (RB) [de

  7. French Regulatory Framework for the Recycling/Reuse of Nuclear Waste and the Dismantling of George Besse Gaseous Diffusion Plant

    Energy Technology Data Exchange (ETDEWEB)

    Themines, R., E-mail: robert.themines@areva.com [AREVA (France)

    2011-07-15

    The regulatory framework in France governing the management of materials containing low levels of radionuclides is described. The plans for the management of the materials arising from the dismantling of the Georges Besse Gaseous Diffusion Plant are described as an example of the application of the regulations. (author)

  8. PGDP [Paducah Gaseous Diffusion Plant]-UF6 handling, sampling, analysis and associated QC/QA and safety related procedures

    International Nuclear Information System (INIS)

    Harris, R.L.

    1987-01-01

    This document is a compilation of Paducah Gaseous Diffusion Plant procedures on UF 6 handling, sampling, and analysis, along with associated QC/QA and safety related procedures. It was assembled for transmission by the US Department of Energy to the Korean Advanced Energy Institute as a part of the US-Korea technical exchange program

  9. Portsmouth Gaseous Diffusion Plant Decontamination and Decommissioning Program surveillance and maintenance plan, FY 1993--2002

    International Nuclear Information System (INIS)

    Schloesslin, W.

    1992-11-01

    The Decontamination and Decommissioning (D ampersand D) Program at the Portsmouth Gaseous Diffusion Plant (PORTS) is part of the Environmental Restoration (ER) and Waste Management (WM) Programs (ERWM). The objective of the ER Program is to provide PORTS the capability to meet applicable environmental regulations through facility development activities and site remedial actions. The WM Program supports the ER Program. The D ampersand D Program provides collective management of the sites within the plant which require decontamination and decommissioning, prioritizes those areas in terms of health, safety and environmental concerns, and implements the appropriate level of remedial action. The D ampersand D Program provides support to facilities which formerly served one or more of the many Plant functions. Program activities include (1) surveillance and maintenance of facilities awaiting decommissioning; (2) planning safe and orderly facility decommissioning; and (3) implementing a program to accomplish facility disposition in a safe, cost effective, and timely manner. In order to achieve the first objective, a formal plan which documents the surveillance and maintenance needs for each inactive facility has been prepared. This report provides this documentation for the PORTS facilities currently included in the D ampersand D Program and includes projected resource requirements for the planning period of FY 1993 through FY 2002

  10. Operating limit study for the proposed solid waste landfill at Paducah Gaseous Diffusion Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D.W.; Wang, J.C.; Kocher, D.C.

    1995-06-01

    A proposed solid waste landfill at Paducah Gaseous Diffusion Plant (PGDP) would accept wastes generated during normal operations that are identified as non-radioactive. These wastes may include small amounts of radioactive material from incidental contamination during plant operations. A site-specific analysis of the new solid waste landfill is presented to determine a proposed operating limit that will allow for waste disposal operations to occur such that protection of public health and the environment from the presence of incidentally contaminated waste materials can be assured. Performance objectives for disposal were defined from existing regulatory guidance to establish reasonable dose limits for protection of public health and the environment. Waste concentration limits were determined consistent with these performance objectives for the protection of off-site individuals and inadvertent intruders who might be directly exposed to disposed wastes. Exposures of off-site individuals were estimated using a conservative, site-specific model of the groundwater transport of contamination from the wastes. Direct intrusion was analyzed using an agricultural homesteader scenario. The most limiting concentrations from direct intrusion or groundwater transport were used to establish the concentration limits for radionuclides likely to be present in PGDP wastes.

  11. Regional flood hazard assessment of the Paducah and Portsmouth Gaseous Diffusion Plants

    International Nuclear Information System (INIS)

    Johnson, R.O.; Wang, J.C.; Lee, D.W.

    1991-01-01

    Regional flood-hazard assessments performed for the Paducah and Portsmouth Gaseous Diffusion Plants are reviewed, compared, and contrasted to determine the relationship of probable maximum flood methodology with respect to US Department of Energy design and evaluation guidelines. The Paducah assessment was carried out using probable minimum flood methodology, while the Portsmouth assessment utilized probabilistic techniques. Results indicated that regional flooding along nearby rivers would not inundate either plant, and that the guidelines were satisfied. A comparison of results indicated that the probable minimum flood recurrence interval associated with the Paducah assessment exceeded the 10,000-year requirement of the guidelines, while recurrence intervals obtained in the Portsmouth assessment could be above or below 10,000 years depending on the choice of the probabilistic model used to perform the assessment. It was concluded, based on an analysis of two data points, that smaller watersheds driven by single event storms could be assessed using probabilistic techniques, while probable maximum flood methodology could be applied to larger drainage basins flooded by storm sequences

  12. Determination of operating limits for radionuclides for a proposed landfill at Paducah Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Wang, J.C.; Lee, D.W.; Ketelle, R.H.; Lee, R.R.; Kocher, D.C.

    1994-01-01

    The operating limits for radionuclides in sanitary and industrial wastes were determined for a proposed landfill at the Paducah Gaseous Diffusion Plant (PGDP), Kentucky. These limits, which may be very small but nonzero, are not mandated by law or regulation but are needed for rational operation. The approach was based on analyses of the potential contamination of groundwater at the plant boundary and the potential exposure to radioactivity of an intruder at the landfill after closure. The groundwater analysis includes (1) a source model describing the disposal of waste and the release of radionuclides from waste to the groundwater, (2) site-specific groundwater flow and contaminant transport calculations, and (3) calculations of operating limits from the dose limit and conversion factors. The intruder analysis includes pathways through ingestion of contaminated vegetables and soil, external exposure to contaminated soil, and inhalation of suspended activity from contaminated soil particles. In both analyses, a limit on annual effective dose equivalent of 4 mrem (0.04 mSv) was adopted. The intended application of the results is to refine the radiological monitoring standards employed by the PGDP Health Physics personnel to determine what constitutes radioactive wastes, with concurrence of the Commonwealth of Kentucky

  13. Operating limit study for the proposed solid waste landfill at Paducah Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Lee, D.W.; Wang, J.C.; Kocher, D.C.

    1995-06-01

    A proposed solid waste landfill at Paducah Gaseous Diffusion Plant (PGDP) would accept wastes generated during normal operations that are identified as non-radioactive. These wastes may include small amounts of radioactive material from incidental contamination during plant operations. A site-specific analysis of the new solid waste landfill is presented to determine a proposed operating limit that will allow for waste disposal operations to occur such that protection of public health and the environment from the presence of incidentally contaminated waste materials can be assured. Performance objectives for disposal were defined from existing regulatory guidance to establish reasonable dose limits for protection of public health and the environment. Waste concentration limits were determined consistent with these performance objectives for the protection of off-site individuals and inadvertent intruders who might be directly exposed to disposed wastes. Exposures of off-site individuals were estimated using a conservative, site-specific model of the groundwater transport of contamination from the wastes. Direct intrusion was analyzed using an agricultural homesteader scenario. The most limiting concentrations from direct intrusion or groundwater transport were used to establish the concentration limits for radionuclides likely to be present in PGDP wastes

  14. Report on the biological monitoring program at Paducah Gaseous Diffusion Plant, January--December 1996

    Energy Technology Data Exchange (ETDEWEB)

    Kszos, L.A. [ed.; Konetsky, B.K.; Peterson, M.J.; Petrie, R.B.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.

    1997-06-01

    On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous diffusion Plant (PGDP). The PGDP BMP was conducted by the University of Kentucky Between 1987 and 1992 and by staff of the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory (ORNL) from 1991 to present. The goals of BMP are to (1) demonstrate that the effluent limitations established for PGDP protect and maintain the use of Little Bayou and Big Bayou creeks for growth and propagation of fish and other aquatic life, (2) characterize potential environmental impacts, and (3) document the effects of pollution abatement facilities on stream. The BMP for PGDP consists of three major tasks: (1) effluent toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities (i.e., benthic macroinvertebrates and fish). This report focuses on ESD activities occurring from January 1996 to December 1996, although activities conducted outside this time period are included as appropriate.

  15. LANMAS alpha configured for Sandia National Laboratories and Paducah Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Woychick, M.R.; Bracey, J.T.; Kern, E.A.; Alvarado, A.

    1993-07-01

    Los Alamos National Laboratory and the Westinghouse Hanford Company have been working jointly for the past 2 years to develop LANMAS (Local Area Network Material Accountability System), the next generation of a US Department of Energy nuclear material accountability system. LANMAS is being designed to reflect the broad-based needs of the US Department of Energy's Material Control ampersand Accountability and Nuclear Materials Management communities, and its developers believe that significant cost savings can be achieved by implementing LANMAS complex-wide, where feasible. LANMAS is being designed so that it is transportable to appropriate US Department of Energy sites. To accomplish this, LANMAS will be configurable to local site work culture. Many US Department of Energy sites are interested in the LANMAS project, and several have participated in its development; some have committed resources. The original LANMAS project team included representatives from the Hanford Site and Los Alamos. As of June 1993, the following sites have also supported the project: Sandia National Laboratory Albuquerque; Sandia National Laboratory Livermore; Paducah Gaseous Diffusion Plant; Lawrence Livermore National Laboratory; Bettis Atomic Power Laboratory; and Knolls Atomic Power Laboratory. In addition, LANMAS is being targeted as a candidate for the US Department of Energy Complex 21, a project designed to restructure the nation's nuclear weapons complex

  16. An aerial radiological survey of the Paducah Gaseous Diffusion Plant and surrounding area, Paducah, Kentucky

    International Nuclear Information System (INIS)

    1992-11-01

    An aerial radiological survey of the Paducah Gaseous Diffusion Plant (PGDP) and surrounding area in Paducah, Kentucky, was conducted during May 15--25, 1990. The purpose of the survey was to measure and document the terrestrial radiological environment at the PGDP and surrounding area for use in effective environmental management and emergency response planning. The aerial survey was flown at an altitude of 61 meters (200 feet) along a series of parallel lines 107 meters (350 feet) apart. The survey encompassed an area of 62 square kilometers (24 square miles), bordered on the north by the Ohio River. The results of the aerial survey are reported as inferred exposure rates at 1 meter above ground level in the form of a gamma radiation contour map. Typical background exposure rates were found to vary from 5 to 12 microroentgens per hour (μR/h). Protactinium-234m, a radioisotope indicative of uranium-238, was detected at several facilities at the PGDR. In support of the aerial survey, ground-based exposure rate and soil sample measurements were obtained at several sites within the survey perimeter. The results of the aerial and ground-based measurements were found to agree within ±15%

  17. Environmental Survey preliminary report, Oak Ridge Gaseous Diffusion Plant, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    1989-02-01

    This report presents the preliminary findings from the first phase of the Environmental Survey of the US Department of Energy's (DOE) Oak Ridge Gaseous Diffusion Plant (ORGDP) conducted March 14 through 25, 1988. The Survey is being conducted by an interdisciplinary team of environmental specialists, led and managed by the Office of Environment, Safety and Health's Office of Environmental Audit. Individual team components are being supplied by a private contractor. The objective of the Survey is to identify environmental risk associated with ORGDP. The Survey covers all environmental media and all areas of environmental regulation. It is being performed in accordance with the DOE Environmental Survey Manual. This phase of the Survey involves the review of existing site environmental data, observations of the operations carried on at ORGDP, and interviews with site personnel. The Survey team developed a Sampling and Analysis Plan to assist in further assessing certain of the environmental problems identified during is on-site activities. The Sampling and Analysis Plan will be executed by Idaho National Engineering Laboratory (INEL). When completed, the results will be incorporated into the ORGDP Survey findings for in inclusion into the Environmental Survey Summary Report. 120 refs., 41 figs., 74 tabs.

  18. Martin Marietta Paducah Gaseous Diffusion Plant comprehensive earthquake emergency management program

    International Nuclear Information System (INIS)

    1990-01-01

    Recognizing the value of a proactive, integrated approach to earthquake preparedness planning, Martin Marietta Energy Systems, Inc. initiated a contract in June 1989 with Murray State University, Murray, Kentucky, to develop a comprehensive earthquake management program for their Gaseous Diffusion Plant in Paducah, Kentucky. The overall purpose of the program is to mitigate the loss of life and property in the event of a major destructive earthquake. The program includes four distinct (yet integrated) components: an emergency management plan, with emphasis on the catastrophic earthquake; an Emergency Operations Center Duty Roster Manual; an Integrated Automated Emergency Management Information System (IAEMIS); and a series of five training program modules. The PLAN itself is comprised of four separate volumes: Volume I -- Chapters 1--3; Volume II -- Chapters 4--6, Volume III -- Chapter 7, and Volume IV -- 23 Appendices. The EOC Manual (which includes 15 mutual aid agreements) is designated as Chapter 7 in the PLAN and is a ''stand alone'' document numbered as Volume III. This document, Volume I, provides an introduction, summary and recommendations, and the emergency operations center direction and control

  19. Report on the biological monitoring program at Paducah Gaseous Diffusion Plant, January-December 1997

    International Nuclear Information System (INIS)

    Kszos, L.A.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.

    1998-03-01

    On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). A plan for the biological monitoring of the receiving streams was implemented in 1987 and consisted of ecological surveys, toxicity monitoring of effluents and receiving streams, evaluation of bioaccumulation of trace contaminants in biota, and supplemental chemical characterization of effluents. Beginning in fall 1991, the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory added data collection and report preparation to its responsibilities for the PGDP BMP. The BMP has been continued because it has proven to be extremely valuable in (1) identifying those effluents with the potential for adversely affecting instream fauna, (2) assessing the ecological health of receiving streams, and (3) guiding plans for remediation and protecting human health. The BMP for PGDP consists of three major tasks: (1) effluent toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of benthic macroinvertebrate communities and fish. With the exception of the benthic macroinvertebrate community surveys, this report focuses on activities from January to December 1997

  20. Operating experience with aluminum bearings at the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Langebrake, C.O.

    1975-01-01

    Considerable operating experience has been gained at the Portsmouth Gaseous Diffusion Plant over the last 15 years in the use of aluminum bearings in process related and auxiliary equipment. All of this experience has been excellent and, in several cases, the use of this type of bearing material has solved significant operating problems. Aluminum 850-T101 alloy was first used as a bearing material in purge cascade (PC-9) centrifugal compressors where a fatigue problem was being experienced with babbitt-type bearings. Good experience in this application led to the extended use of this bearing material in other equipment including process related as well as auxiliary equipment. Since 1961 aluminum bearings have been installed in approximately 21 Type PC-9 (centrifugal), 97 Type 9 (centrifugal), 262 Type X-29 (axial), and 101 Type 31 (axial) compressors, and 3 speed increasers in the X-330 Evacuation Booster Station. Based on successful operation of these bearings, continued and expanded use of aluminum bearings is recommended as a means of obtaining a high fatigue resistant bearing at a cost lower than that for babbitt-type bearings. (U.S.)

  1. Proposed sale of radioactively contaminated nickel ingots located at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    International Nuclear Information System (INIS)

    1995-10-01

    The U.S. Department of Energy (DOE) proposes to sell 8,500 radioactively contaminated nickel ingots (9.350 short tons), currently in open storage at the Paducah Gaseous Diffusion Plant (PGDP), to Scientific Ecology Group, Inc. (SEG) for decontamination and resale on the international market. SEG would take ownership of the ingots when they are loaded for transport by truck to its facility in Oak Ridge, Tennessee. SEG would receive approximately 200 short tons per month over approximately 48 months (an average of 180 ingots per month). The nickel decontamination process specified in SEG's technical proposal is considered the best available technology and has been demonstrated in prototype at SEG. The resultant metal for resale would have contamination levels between 0.3 and 20 becquerel per gram (Bq/g). The health hazards associated with release of the decontaminated nickel are minimal. The activity concentration of the end product would be further reduced when the nickel is combined with other metals to make stainless steel. Low-level radioactive waste from the SEG decontamination process, estimated to be approximately 382 m 3 (12,730 ft), would be shipped to a licensed commercial or DOE disposal facility. If the waste were packaged in 0.23 m 3 -(7.5 ft 3 -) capacity drums, approximately 1,500 to 1,900 drums would be transported over the 48-month contract period. Impacts from the construction of decontamination facilities and the selected site are minimal

  2. Report on the biological monitoring program at Paducah Gaseous Diffusion Plant, January--December 1997

    Energy Technology Data Exchange (ETDEWEB)

    Kszos, L.A.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.

    1998-03-01

    On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). A plan for the biological monitoring of the receiving streams was implemented in 1987 and consisted of ecological surveys, toxicity monitoring of effluents and receiving streams, evaluation of bioaccumulation of trace contaminants in biota, and supplemental chemical characterization of effluents. Beginning in fall 1991, the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory added data collection and report preparation to its responsibilities for the PGDP BMP. The BMP has been continued because it has proven to be extremely valuable in (1) identifying those effluents with the potential for adversely affecting instream fauna, (2) assessing the ecological health of receiving streams, and (3) guiding plans for remediation and protecting human health. The BMP for PGDP consists of three major tasks: (1) effluent toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of benthic macroinvertebrate communities and fish. With the exception of the benthic macroinvertebrate community surveys, this report focuses on activities from January to December 1997.

  3. Report on the biological monitoring program at Paducah Gaseous Diffusion Plant December 1993 to December 1994

    Energy Technology Data Exchange (ETDEWEB)

    Kszos, L.A. [ed.

    1996-05-01

    On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). The PGDP BMP was implemented in 1987 by the University of Kentucky. Research staff of the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory (ORNL) served as reviewers and advisers to the University of Kentucky. Beginning in fall 1991, ESD added data collection and report preparation to its responsibilities for the PGDP BMP. The goals of BMP are to (1) demonstrate that the effluent limitations established for PGDP protect and maintain the use of Little Bayou and Big Bayou creeks for growth and propagation of fish and other aquatic life, (2) characterize potential environmental impacts, (3) document the effects of pollution abatement facilities on stream biota, and (4) recommend any program improvements that would increase effluent treatability. In September 1992, a renewed Kentucky Pollutant Discharge Elimination System (KPDES) permit was issued to PGDP. The BMP for PGDP consists of three major tasks: (1) effluent and ambient toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities (i.e., benthic macroinvertebrates and fish). This report includes ESD activities occurring from December 1993 to December 1994, although activities conducted outside this time period are included as appropriate.

  4. Report on the biological monitoring program at Paducah Gaseous Diffusion Plant December 1993 to December 1994

    International Nuclear Information System (INIS)

    Kszos, L.A.

    1996-05-01

    On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous Diffusion Plant (PGDP). The PGDP BMP was implemented in 1987 by the University of Kentucky. Research staff of the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory (ORNL) served as reviewers and advisers to the University of Kentucky. Beginning in fall 1991, ESD added data collection and report preparation to its responsibilities for the PGDP BMP. The goals of BMP are to (1) demonstrate that the effluent limitations established for PGDP protect and maintain the use of Little Bayou and Big Bayou creeks for growth and propagation of fish and other aquatic life, (2) characterize potential environmental impacts, (3) document the effects of pollution abatement facilities on stream biota, and (4) recommend any program improvements that would increase effluent treatability. In September 1992, a renewed Kentucky Pollutant Discharge Elimination System (KPDES) permit was issued to PGDP. The BMP for PGDP consists of three major tasks: (1) effluent and ambient toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities (i.e., benthic macroinvertebrates and fish). This report includes ESD activities occurring from December 1993 to December 1994, although activities conducted outside this time period are included as appropriate

  5. Environmental Survey preliminary report, Oak Ridge Gaseous Diffusion Plant, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1989-02-01

    This report presents the preliminary findings from the first phase of the Environmental Survey of the US Department of Energy's (DOE) Oak Ridge Gaseous Diffusion Plant (ORGDP) conducted March 14 through 25, 1988. The Survey is being conducted by an interdisciplinary team of environmental specialists, led and managed by the Office of Environment, Safety and Health's Office of Environmental Audit. Individual team components are being supplied by a private contractor. The objective of the Survey is to identify environmental risk associated with ORGDP. The Survey covers all environmental media and all areas of environmental regulation. It is being performed in accordance with the DOE Environmental Survey Manual. This phase of the Survey involves the review of existing site environmental data, observations of the operations carried on at ORGDP, and interviews with site personnel. The Survey team developed a Sampling and Analysis Plan to assist in further assessing certain of the environmental problems identified during is on-site activities. The Sampling and Analysis Plan will be executed by Idaho National Engineering Laboratory (INEL). When completed, the results will be incorporated into the ORGDP Survey findings for in inclusion into the Environmental Survey Summary Report. 120 refs., 41 figs., 74 tabs

  6. Martin Marietta Paducah Gaseous Diffusion Plant comprehensive earthquake emergency management program

    International Nuclear Information System (INIS)

    1990-01-01

    Recognizing the value of a proactive, integrated approach to earthquake preparedness planning, Martin Marietta Energy Systems, Inc. initiated a contract in June 1989 with Murray State University, Murray, Kentucky, to develop a comprehensive earthquake management program for their Gaseous Diffusion Plant in Paducah, Kentucky (PGDP -- Subcontract No. 19P-JV649V). The overall purpose of the program is to mitigate the loss of life and property in the event of a major destructive earthquake. The program includes four distinct (yet integrated) components: an emergency management plan, with emphasis on the catastrophic earthquake; an Emergency Operations Center Duty Roster Manual; an Integrated Automated Emergency Management Information System (IAEMIS); and a series of five training program modules. The PLAN itself is comprised of four separate volumes: Volume I -- Chapters 1--3; Volume II -- Chapters 4--6, Volume III -- Chapter 7, and Volume IV -- 23 Appendices. The EOC Manual (which includes 15 mutual aid agreements) is designated as Chapter 7 in the PLAN and is a ''stand alone'' document numbered as Volume III. This document, Volume II, discusses methodology, engineering and environmental analyses, and operational procedures

  7. Martin Marietta Paducah Gaseous Diffusion Plant comprehensive earthquake emergency management program

    International Nuclear Information System (INIS)

    1990-01-01

    Recognizing the value of a proactive, integrated approach to earthquake preparedness planning, Martin Marietta Energy Systems, Inc, initiated a contract in June 1989 with Murray State University, Murray, Kentucky, to develop a comprehensive earthquake management program for their Gaseous Diffusion Plant in Paducah, Kentucky (PGDP--Subcontract No. 19P-JV649V). The overall purpose of the program is to mitigate the loss of life and property in the event of a major destructive earthquake. The program includes four distinct (yet integrated) components: (1) an emergency management plan, with emphasis on the catas trophic earthquake, (2) an Emergency Operations Center Duty Roster Manual, (3) an Integrated Automated Emergency Management Information System (IAEMIS), and (4) a series of five training program modules. The PLAN itself is comprised of four separate volumes: Volume I--Chapters 1--3; Volume II--Chapters 4--6, Volume III--Chapter 7, and Volume IV--23 Appendices. The EOC Manual (which includes 15 mutual aid agreements) is designated as Chapter 7 in the PLAN and is a ''stand alone'' document numbered as Volume III. This document, Volume IV contains the appendices to this report

  8. Application of a Kalman filter to UF6 gaseous diffusion plant freezer/sublimer systems

    International Nuclear Information System (INIS)

    Ruppel, F.R.

    1992-03-01

    A signal is required to control the flow of UF 6 in gaseous diffusion plant freezer/sublimer systems. The original strategy envisioned for deriving a flow signal was to take the derivative of the freezer/sublimer weigh cell signal. However, the derivative of the digitized weight signal is noisy, preventing good control. In addition, a bias is introduced into the weight derivative signal because a refrigerant is circulated through a shell-and-tube heat exchanger inside the freezer/sublimer. The weight of the refrigerant is included in the weight measured by the weigh cell. If the circulation rate of the refrigerent is not steady state, a bias exists. Measurements of upstream pressure, vessel pressure, and output to the system control valve are available to the control system. Thus, if the flow through the control valve is characterized properly by the measurements, a Kalman filter can be used in conjunction with these auxiliary inputs and the weigh cell input to overcome the noise and bias problem and provide an improve estimate of flow rate. A discussion of the development and the current status of a Kalman filter used for this application is given. 5 refs

  9. Martin Marietta Paducah Gaseous Diffusion Plant comprehensive earthquake emergency management program

    International Nuclear Information System (INIS)

    1990-01-01

    Recognizing the value of a proactive, integrated approach to earthquake preparedness planning, Martin Marietta Energy Systems, Inc. initiated a contract in June 1989 with Murray State University, Murray, Kentucky, to develop a comprehensive earthquake management program for their Gaseous Diffusion Plant in Paducah, Kentucky (PGDP -- Subcontract No. 19P-JV649V). The overall purpose of the program is to mitigate the loss of life and property in the event of a major destructive earthquake. The program includes four distinct (yet integrated) components: (1) an emergency management plan with emphasis on the catas trophic earthquake; (2) an Emergency Operations Center Duty Roster Manual; (3) an Integrated Automated Emergency Management Information System (IAEMIS); and (4) a series of five training program modules. The PLAN itself is comprised of four separate volumes: Volume I -- Chapters 1--3; Volume II -- Chapters 4--6; Volume III -- Chapter 7; and Volume IV -- 23 Appendices. The EOC Manual (which includes 15 mutual aid agreements) is designated as Chapter 7 in the PLAN and is this document numbered as Volume III

  10. Assessment and interpretation of cross- and down-hole seismograms at the Paducah Gaseous Diffusion Plant

    Energy Technology Data Exchange (ETDEWEB)

    Staub, W.P.; Wang, J.C. (Oak Ridge National Lab., TN (United States)); Selfridge, R.J. (Automated Sciences Group, (United States))

    1991-09-01

    This paper is an assessment and interpretation of cross-and down-hole seismograms recorded at four sites in the vicinity of the Paducah Gaseous Diffusion Plant (PGDP). Arrival times of shear (S-) and compressional (P-) waves are recorded on these seismograms in milliseconds. Together with known distances between energy sources and seismometers lowered into boreholes, these arrival times are used to calculate S- and P-wave velocities in unconsolidated soils and sediments that overlie bedrock approximately 320 ft beneath PGDP. The soil columns are modified after an earlier draft by ERC Environmental and Energy Services Company (ERCE), 1990. In addition to S- and P- wave velocity estimates from this paper, the soil columns contain ERCE's lithologic and other geotechnical data for unconsolidated soils and sediments from the surface to bedrock. Soil columns for Sites 1 through 4 and a site location map are in Plates 1 through 5 of Appendix 6. The velocities in the four columns are input parameters for the SHAKE computer program, a nationally recognized computer model that simulates ground response of unconsolidated materials to earthquake generated seismic waves. The results of the SHAKE simulation are combined with predicted ground responses on rock foundations (caused by a given design earthquake) to predict ground responses of facilities with foundations placed on unconsolidated materials. 3 refs.

  11. Report on the biological monitoring program at Paducah Gaseous Diffusion Plant, January - December 1996

    International Nuclear Information System (INIS)

    Kszos, L.A.; Konetsky, B.K.; Peterson, M.J.; Petrie, R.B.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.

    1997-06-01

    On September 24, 1987, the Commonwealth of Kentucky Natural Resources and Environmental Protection Cabinet issued an Agreed Order that required the development of a Biological Monitoring Program (BMP) for the Paducah Gaseous diffusion Plant (PGDP). The PGDP BMP was conducted by the University of Kentucky Between 1987 and 1992 and by staff of the Environmental Sciences Division (ESD) at Oak Ridge National Laboratory (ORNL) from 1991 to present. The goals of BMP are to (1) demonstrate that the effluent limitations established for PGDP protect and maintain the use of Little Bayou and Big Bayou creeks for growth and propagation of fish and other aquatic life, (2) characterize potential environmental impacts, and (3) document the effects of pollution abatement facilities on stream. The BMP for PGDP consists of three major tasks: (1) effluent toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities (i.e., benthic macroinvertebrates and fish). This report focuses on ESD activities occurring from January 1996 to December 1996, although activities conducted outside this time period are included as appropriate

  12. Structural inspection and wind analysis of redwood cooling towers at the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Chung, T.; Solack, T.; Hortel, J.

    1991-01-01

    As part of the plant upgrade program, structural analyses and field inspections were performed on four redwood cooling towers at the DOE Portsmouth gaseous diffusion plant located in Piketon, Ohio. The cooling towers are categorized as important hazard facilities. The loadings are derived from UCRL-15910 according to the pertinent hazard category. In addition to the seismic and wind loadings, the wood cooling towers are constantly subject to adverse environmental effects such as elevated temperature, chemical attack, icing and snow load, and motor vibrations. A thorough structural evaluation for all load combinations was performed for each of the cooling towers based on the structural code requirements of the Cooling Tower Institute and National Forest Products Association. Most stress criteria are unique for the redwood material. This evaluation was performed using finite element techniques on the global structural integrity and supplemented by hand calculations on the individual connection joints. Overloaded wood structural members and joints are identified by the analysis. The rectangular tower structure sits on a concrete basin that span across 60 ft by 200 ft. A major part of the cooling towers upgrading program involved field inspections of the individual cells of each tower. The primary purpose of these inspections was to identify any existing structural damage or deficiencies such as failed members, degraded wood, and deficiencies resulting from poor construction practice. Inspection of 40 cells identified some generic deficiencies that mostly are consistent with the analytical finding. Based on the analysis, some effective but inexpensive upgrading techniques were developed and recommended to bring the cooling towers into compliance with current DOE requirements

  13. Inorganic soil and groundwater chemistry near Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    International Nuclear Information System (INIS)

    Moore, G.K.

    1995-03-01

    Near-surface soils, boreholes, and sediments near the Paducah Gaseous Diffusion Plant (PGDP) were sampled in 1989-91 as were monitoring wells, TVA wells, and privately-owned wells. Most wells were sampled two or three times. The resulting chemical analyses have been published in previous reports and have been previously described (CH2M HILL 1991, 1992; Clausen et al. 1992). The two reports by CH2M HILL are controversial, however, because, the concentrations of some constituents were reported to exceed background levels or drinking water standards and because both on-site (within the perimeter fence at PGDP) and off-site pollution was reported to have occurred. The groundwater samples upon which these interpretations were based may not be representative, however. The CH2M HILL findings are discussed in the report. The purpose of this report is to characterize the inorganic chemistry of groundwater and soils near PGDP, using data from the CH2M HILL reports (1991, 1992), and to determine whether or not any contamination has occurred. The scope is limited to analysis and interpretation of data in the CH2M HILL reports because previous interpretations of these data may not be valid, because samples were collected in a relatively short period of time at several hundred locations, and because the chemical analyses are nearly complete. Recent water samples from the same wells were not considered because the characterization of inorganic chemistry for groundwater and soil requirements only one representative sample and an accurate analysis from each location

  14. Inorganic soil and groundwater chemistry near Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    Moore, G.K. [Tennessee Univ., Knoxville, TN (United States)

    1995-03-01

    Near-surface soils, boreholes, and sediments near the Paducah Gaseous Diffusion Plant (PGDP) were sampled in 1989-91 as were monitoring wells, TVA wells, and privately-owned wells. Most wells were sampled two or three times. The resulting chemical analyses have been published in previous reports and have been previously described (CH2M HILL 1991, 1992; Clausen et al. 1992). The two reports by CH2M HILL are controversial, however, because, the concentrations of some constituents were reported to exceed background levels or drinking water standards and because both on-site (within the perimeter fence at PGDP) and off-site pollution was reported to have occurred. The groundwater samples upon which these interpretations were based may not be representative, however. The CH2M HILL findings are discussed in the report. The purpose of this report is to characterize the inorganic chemistry of groundwater and soils near PGDP, using data from the CH2M HILL reports (1991, 1992), and to determine whether or not any contamination has occurred. The scope is limited to analysis and interpretation of data in the CH2M HILL reports because previous interpretations of these data may not be valid, because samples were collected in a relatively short period of time at several hundred locations, and because the chemical analyses are nearly complete. Recent water samples from the same wells were not considered because the characterization of inorganic chemistry for groundwater and soil requirements only one representative sample and an accurate analysis from each location.

  15. Modeling and analyses of postulated UF6 release accidents in gaseous diffusion plant

    International Nuclear Information System (INIS)

    Kim, S.H.; Taleyarkhan, R.P.; Keith, K.D.; Schmidt, R.W.; Carter, J.C.; Dyer, R.H.

    1995-10-01

    Computer models have been developed to simulate the transient behavior of aerosols and vapors as a result of a postulated accident involving the release of uranium hexafluoride (UF 6 ) into the process building of a gaseous diffusion plant. UF 6 undergoes an exothermic chemical reaction with moisture (H 2 O) in the air to form hydrogen fluoride (HF) and radioactive uranyl fluoride (UO 2 F 2 ). As part of a facility-wide safety evaluation, this study evaluated source terms consisting of UO 2 F 2 as well as HF during a postulated UF 6 release accident in a process building. In the postulated accident scenario, ∼7900 kg (17,500 lb) of hot UF 6 vapor is released over a 5 min period from the process piping into the atmosphere of a large process building. UO 2 F 2 mainly remains as airborne-solid particles (aerosols), and HF is in a vapor form. Some UO 2 F 2 aerosols are removed from the air flow due to gravitational settling. The HF and the remaining UO 2 F 2 are mixed with air and exhausted through the building ventilation system. The MELCOR computer code was selected for simulating aerosols and vapor transport in the process building. MELCOR model was first used to develop a single volume representation of a process building and its results were compared with those from past lumped parameter models specifically developed for studying UF 6 release accidents. Preliminary results indicate that MELCOR predicted results (using a lumped formulation) are comparable with those from previously developed models

  16. In Situ Chemical Oxidation Through Lance Permeation at the Portsmouth Gaseous Diffusion Plant (PORTS)

    International Nuclear Information System (INIS)

    Martin, M.Z.

    2003-01-01

    In situ chemical oxidation through lance permeation (ISCO-LP) is an emerging remediation technology in which chemical oxidants (such as potassium or sodium permanganate) are delivered to the subsurface using vertical lance-like injectors. It is applicable to sites with oxidizable contaminants such as chlorinated solvents and fuel hydrocarbons. Because vertical lance injections can be deployed at relatively close spacing, ISCO-LP potentially can be used to clean-up contamination in low-permeability media. This document provides information that can help potential users determine whether ISCO-LP would apply to a particular environmental management problem. It contains a general description of the technology (Section 2), performance data from a field demonstration (Section 3), an assessment of technology applicability (Section 4), a summary of cost elements (Section 5), and a list of regulatory, environmental safety and health issues (Section 6). It is patterned after the Innovative Technology Summary Reports (ITSR) published by the Department of Energy's (DOE) Office of Science and Technology under the Subsurface Contaminants Focus Area (SCFA). As in the previously published ITSRs, the technology described in this report was developed through funding from SCFA. Most of the information contained in this report was obtained from a field demonstration of ISCO-LP conducted in July-August 2000 at DOE's Portsmouth Gaseous Diffusion Plant (PORTS). The field test was not completed due to an accident that caused a field worker serious injuries. Although performance assessment data are very limited, the field test highlighted important health and safety issues that must be considered by site managers and technology vendors interested in implementing ISCO-LP

  17. Cooling tower drift studies at the Paducah, Kentucky Gaseous Diffusion Plant. [Transport of drift-derived chromium in terrestrial ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, F.G.; Hanna, S.R.; Parr, P.D.

    1979-01-01

    The transfer and fate of chromium from cooling tower drift to terrestrial ecosystems were quantified at the Department of Energy's uranium enrichment facility at Paducah, Kentucky. Chromium concentrations in plant materials (fescue grass) decreased with increasing distance from the cooing tower, ranging from 251 +- 19 ppM at 15 meters to 0.52 +- 0.07 ppM at 1500 meters. The site of drift contamination, size characteristics, and elemental content of drift particles were determined using a scanning electron microscope with energy dispersive x-ray analysis capabilities. Results indicate that elemental content in drift water (mineral residue) may not be equivalent to the content in the recirculating cooling water of the tower. This hypothesis is contrary to basic assumptions in calculating drift emissions. A laboratory study simulating throughfall from 1 to 6 inches of rain suggested that there are more exchange sites associated with litter than live foliage. Leachate from each one inch throughfall simulant removed 3% of the drift mass from litter compared to 7 to 9% from live foliage. Results suggest that differences in retention are related to chemical properties of the drift rather than physical lodging of the particle residue. To determine the potential for movement of drift-derived chromium to surface streams, soil--water samplers (wells) were placed along a distance gradient to Little Bayou Creek. Samples from two depths following rainstorms revealed the absence of vertical or horizontal movement with maximum concentrations of 0.13 ppb at 50 meters from the tower. Preliminary model estimates of drift deposition are compared to depositionmeasurements. Isopleths of the predicted deposition are useful to identify areas of maximum drift transport in the environs of the gaseous diffusion plant.

  18. Laser and gaseous diffusion

    International Nuclear Information System (INIS)

    Schneider-Maunoury, A.; Decool, F.

    1986-06-01

    The aim is to compare these two technologies, for uranium enrichment, to underline the certainties and uncertainties surrounding wrap their challenge, and to see how they will contribute, with their specific characteristics, to provide a continuous and reliable source of supply of enrichment services, from now to the next century

  19. Final environmental impact assessment of the Paducah Gaseous Diffusion Plant site, Paducah, Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    1982-08-01

    This document considers: the need for uranium enrichment facilities; site location; plant description; and describes the power generating facilities in light of its existing environment. The impacts from continuing operations are compared with alternatives of shutdown, relocation, and alternative power systems. (PSB)

  20. Generic report on health effects for the US Gaseous Diffusion Plants. Sect. 8, Pt. 1

    International Nuclear Information System (INIS)

    Just, R.A.; Emler, V.S.

    1984-06-01

    Toxic substances present in uranium enrichment plants include uranium hexafluoride (UF 6 ), hydrogen fluoride (HF), uranyl fluoride (UO 2 F 2 ), chlorine (Cl 2 ), chlorine trifluoride (ClF 3 ), fluorine (F 2 ), uranium tetrafluoride (UF 4 ), and technetium (Tc). The current knowledge of the expected health effects of acute exposures to these substances is described. 10 references, 2 figures, 6 tables

  1. Concentration transients in a gaseous diffusion plant (1961); Cinetique des concentrations dans une usine de separation isotopique (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Jacques, R; Bilous, O [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1961-07-01

    Concentration transients are examined in the case of a gaseous diffusion plant for uranium isotope separation. An application is made for a plant built with two rectifying cascades of different sizes and a stripping cascade. Transients are calculated for a change in the feed concentration, the transport and also for shutdown of a group of separating stages in one of the cascades. (authors) [French] On examine l'evolution des concentrations dans une usine de separation isotopique de l'uranium basee sur le procede de diffusion gazeuse et formee de cascades carrees. Une application est faite pour une installation formee de deux cascades enrichissantes de tailles differentes et d'une cascade appauvrissante. On calcule en particulier les regimes transitoires apres variation de la concentration d'alimentation, du transport et apres mise hors circuit d'un groupe d'etages dans l'une des cascades. (auteurs)

  2. Analog simulation of concentration transients in a gaseous diffusion plant (1961); Etude sur simulateur des regimes transitoires des concentrations dans une installation de diffusion gazeuse (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Delarousse, P; Trouve, C; Jacques, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-07-01

    A finite difference system is used to describe concentration transients in a gaseous diffusion plant for uranium isotope separation. The equipment used in this study is described and examples are given to illustrate the problems which have been solved with it. (authors) [French] Le comportement transitoire d'une cascade de diffusion gazeuse est represente de facon approchee par un systeme differentiel aux differences. On decrit le materiel analogique original qui a permis de simuler ce systeme. Une serie d'exemples illustre les differents problemes qui ont ete resolus au moyen de cet appareil. (auteurs)

  3. Rate of Contamination Removal of Two Phyto-remediation Sites at the DOE Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Lewis, A.C.; Baird, D.R.

    2006-01-01

    This paper describes applications of phyto-remediation at the Portsmouth Gaseous Diffusion Plant (PORTS), a Department of Energy (DOE) Facility that enriched uranium from the early 1950's until 2000. Phyto-remediation has been implemented to assist in the removal of TCE (trichloroethylene) in the groundwater at two locations at the PORTS facility: the X-740 area and the X-749/X-120 area. Phyto-remediation technology is based on the ability of certain plants species (in this case hybrid poplar trees) and their associated rhizo-spheric microorganisms to remove, degrade, or contain chemical contaminants located in the soil, sediment, surface water, groundwater, and possibly even the atmosphere. Phyto-remediation technology is a promising clean-up solution for a wide variety of pollutants and sites. Mature trees, such as the hybrid poplar, can consume up to 3,000 gallons of groundwater per acre per day. Organic compounds are captured in the trees' root systems. These organic compounds are degraded by ultraviolet light as they are transpired along with the water vapor through the leaves of the trees. The phyto-remediation system at the X-740 area encompasses 766 one-year old hybrid poplar trees (Populus nigra x nigra, Populus nigra x maximowiczii, and Populus deltoides x nigra) that were planted 10 feet apart in rows 10 feet to 20 feet apart, over an area of 2.6 acres. The system was installed to manage the VOC contaminant plume. At the X749/X-120 area, a phyto-remediation system of 2,640 hybrid poplar trees (Populus nigra x maximowiczii) was planted in seven areas/zones to manage the VOC contaminant plume. The objectives of these systems are to remove contamination from the groundwater and to prevent further migration of contaminants. The goal of these remediation procedures is to achieve completely mature and functional phyto-remediation systems within two years of the initial planting of the hybrid poplar trees at each planting location. There is a direct

  4. An interim report to the manager of the Paducah Gaseous Diffusion Plant from the Paducah Environmental Advisory Committee

    International Nuclear Information System (INIS)

    Jackson, G.D.

    1987-01-01

    The Paducah Environmental Advisory Committee was formed as: (1) an outgrowth of other Environmental Advisory Committees already in existence at Oak Ridge and other Martin Marietta Energy Systems plants; (2) a result of public concern following significant nuclear incidents at Bhopal and Chernobyl; (3) a result of the new direction and commitment of the management of the Paducah Gaseous Diffusion Plant following contract acquisition by Martin Marietta Energy Systems; and (4) a means of reducing and/or preventing local and/or public concern regarding the activities of and potential risks created by PGDP. This report discusses the following issues and concerns of the Committee arrived at through a series of meetings: (1) groundwater monitoring; (2) long-range tails storage; C-404, scrap yrads, and PCB and TCE cleanup; nuclear criticality plan and alarm systems; documentation of historical data regarding hazardous waste burial grounds; dosimeter badges; and asbestos handling and removal

  5. An interim report to the manager of the Paducah Gaseous Diffusion Plant from the Paducah Environmental Advisory Committee

    International Nuclear Information System (INIS)

    Jackson, G.D.

    1987-10-01

    The Paducah Environmental Advisory Committee was formed as: (1) an outgrowth of other Environmental Advisory Committees already in existence at Oak Ridge and other Martin Marietta Energy Systems plants; (2) a result of public concern following significant nuclear incidents at Bhopal and Chernobyl; (3) a result of the new direction and commitment of the management of the Paducah Gaseous Diffusion Plant following contract acquisition by Martin Marietta Energy Systems; and (4) a means of reducing and/or preventing local and/or public concern regarding the activities of and potential risks created by PGDP. This report discusses the following issues and concerns of the Committee arrived at through a series of meetings: (1) groundwater monitoring; (2) long-range tails storage; C-404, scrap yrads, and PCB and TCE cleanup; nuclear criticality plan and alarm systems; documentation of historical data regarding hazardous waste burial grounds; dosimeter badges; and asbestos handling and removal

  6. Long-term mortality study of workers occupationally exposed to metallic nickel at the Oak Ridge Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Godbold, J.H. Jr.; Tompkins, E.A.

    1979-01-01

    This study was undertaken to determine whether mortality from respiratory cancer among workers occupationally exposed to metallic nickel at the Oak Ridge Gaseous Diffusion Plant (ORGDP) differed from that of workers at the same plant with no record of occupational exposure to metallic nickel or any nickel compound. A cohort of 814 nickel-exposed workers and one of 1600' controls were identified. The members of both cohorts had a minimum follow-up period of 19 years. Mortality from respiratory cancer and from other causes was examined in both groups. The data showed no evidence of an increased risk of mortality due to respiratory cancer among the nickel-exposed workers. The exposed cohort experienced lower mortality than the controls, both in deaths due to respiratory cancer and in deaths due to all causes, although neither of these differences was statistically significant

  7. Gamma radiological surveys of the Oak Ridge Reservation, Paducah Gaseous Diffusion Plant, and Portsmouth Gaseous Diffusion Plant, 1990-1993, and overview of data processing and analysis by the Environmental Restoration Remote Sensing Program, Fiscal Year 1995

    International Nuclear Information System (INIS)

    Smyre, J.L.; Moll, B.W.; King, A.L.

    1996-06-01

    Three gamma radiological surveys have been conducted under auspices of the ER Remote Sensing Program: (1) Oak Ridge Reservation (ORR) (1992), (2) Clinch River (1992), and (3) Portsmouth Gaseous Diffusion Plant (PORTS) (1993). In addition, the Remote Sensing Program has acquired the results of earlier surveys at Paducah Gaseous Diffusion Plant (PGDP) (1990) and PORTS (1990). These radiological surveys provide data for characterization and long-term monitoring of U.S. Department of Energy (DOE) contamination areas since many of the radioactive materials processed or handled on the ORR, PGDP, and PORTS are direct gamma radiation emitters or have gamma emitting daughter radionuclides. High resolution airborne gamma radiation surveys require a helicopter outfitted with one or two detector pods, a computer-based data acquisition system, and an accurate navigational positioning system for relating collected data to ground location. Sensors measure the ground-level gamma energy spectrum in the 38 to 3,026 KeV range. Analysis can provide gamma emission strength in counts per second for either gross or total man-made gamma emissions. Gross count gamma radiation includes natural background radiation from terrestrial sources (radionuclides present in small amounts in the earth's soil and bedrock), from radon gas, and from cosmic rays from outer space as well as radiation from man-made radionuclides. Man-made count gamma data include only the portion of the gross count that can be directly attributed to gamma rays from man-made radionuclides. Interpretation of the gamma energy spectra can make possible the determination of which specific radioisotopes contribute to the observed man-made gamma radiation, either as direct or as indirect (i.e., daughter) gamma energy from specific radionuclides (e.g., cesium-137, cobalt-60, uranium-238)

  8. Handling and treatment of low-level radioactive wastes from gaseous diffusion plants in the United States of America

    International Nuclear Information System (INIS)

    Wing, J.F.; Behrend, J.E.

    1984-01-01

    Gaseous diffusion plants in the United States of America currently generate very small quantities of low-level radioactive wastes. These wastes consist primarily of airborne effluent solid trapping media and liquid scrubber solutions, liquid effluent treatment sludges, waste oils and solvents, scrap metals and conventional combustible wastes such as floor sweepings, cleaning rags and shoe covers. In addition to waste emanating from current operations, large quantities of scrap metal generated during the Cascade Improvement Program are stored above ground at each of the diffusion plants. The radionuclides of primary concern are uranium and 99 Tc. Current radioactive waste treatment consists of uranium dissolution in weak acids followed by chemical precipitation and/or solvent extraction for uranium recovery. Current disposal operations consist of above ground storage of scrap metals, shallow land burial of inorganic solids and incineration of combustible wastes. With increased emphasis on reducing the potential for off-site radiological dose, several new treatment and disposal options are being studied and new projects are being planned. One project of particular interest involves the installation of a high temperature incinerator to thermally degrade hazardous organic wastes contaminated with low-level radioactive wastes. Other technologies being studied include fixation of uranium-bearing sludges in concrete before burial, decontamination of scrap metals by smelting and use of specially engineered centralized burial grounds. (author)

  9. Dispersion of UO2F2 aerosol and HF vapor in the operating floor during winter ventilation at the Paducah Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Kim, S.H.; Chen, N.C.J.; Taleyarkhan, R.P.; Keith, K.D.; Schmidt, R.W.; Carter, J.C.

    1996-01-01

    The gaseous diffusion process is currently employed at two plants in the US: the Paducah Gaseous Diffusion Plant and the Portsmouth Gaseous Diffusion Plant. As part of a facility-wide safety evaluation, a postulated design basis accident involving large line-rupture induced releases of uranium hexafluoride (UF 6 ) into the process building of a gaseous diffusion plant (GDP) is evaluated. When UF 6 is released into the atmosphere, it undergoes an exothermic chemical reaction with moisture (H 2 O) in the air to form vaporized hydrogen fluoride (HF) and aerosolized uranyl fluoride (UO 2 F 2 ). These reactants disperse in the process building and transport through the building ventilation system. The ventilation system draws outside air into the process building, distributes it evenly throughout the building, and discharges it to the atmosphere at an elevated temperature. Since air is recirculated from the cell floor area to the operating floor, issues concerning in-building worker safety and evacuation need to be addressed. Therefore, the objective of this study is to evaluate the transport of HF vapor and UO 2 F 2 aerosols throughout the operating floor area following B-line break accident in the cell floor area

  10. Nuclear criticality safety controls for uranium deposits during D and D at the Oak Ridge Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Haire, M.J.; Jordan, W.C.; Jollay, L.J. III; Dahl, T.L.

    1997-01-01

    The US Department of Energy (DOE) Deputy Assistant Secretary of Energy for Environmental Management has issued a challenge to complete DOE environmental cleanup within a decade. The response for Oak Ridge facilities is in accordance with the DOE ten-year plan which calls for completion of > 95% of environmental management work by the year 2006. This will result in a 99% risk reduction and in a significant savings in base line costs in waste management (legacy waste); remedial action (groundwater, soil, etc.); and decontamination and decommissioning (D and D). It is assumed that there will be long-term institutional control of cascade equipment, i.e., there will be no walk away from sites, and that there will be firm radioactivity release limits by 1999 for recycle metals. An integral part of these plants is the removal of uranium deposits which pose nuclear criticality safety concerns in the shut down of the Oak Ridge Gaseous Diffusion Plant. DOE has initiated the Nuclear Criticality Stabilization Program to improve nuclear criticality safety by removing the larger uranium deposits from unfavorable geometry equipment. Nondestructive assay (NDA) measurements have identified the location of these deposits. The objective of the K-25 Site Nuclear Criticality Stabilization Program is to remove and place uranium deposits into safe geometry storage containers to meet the double contingency principle. Each step of the removal process results in safer conditions where multiple controls are present. Upon completion of the Program, nuclear criticality risks will be greatly reduced

  11. Minimum critical masses for uranium at the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Tayloe, R.W. Jr.; Davis, T.C.

    1994-06-01

    This report presents a tabulation of safe masses and minimum critical masses for uranium (U). These minimum critical mass and safe mass tables were obtained by interpolating between the values reported in the literature to obtain values as a function of enrichment within the 1.5 percent to 100 percent range. Equivalent mass values for uranium-235 (U 235 ), uranium hexafluoride (UF 6 ), and uranyl fluoride (UO 2 F 2 ) have been generated from the safe mass and minimum critical masses for uranium

  12. Determination of the response function for the Portsmouth Gaseous Diffusion Plant criticality accident alarm system neutron detectors

    International Nuclear Information System (INIS)

    Tayloe, R.W. Jr.; Brown, A.S.; Dobelbower, M.C.; Woollard, J.E.

    1997-03-01

    Neutron-sensitive radiation detectors are used in the Portsmouth Gaseous Diffusion Plant's (PORTS) criticality accident alarm system (CAAS). The CAAS is composed of numerous detectors, electronics, and logic units. It uses a telemetry system to sound building evacuation horns and to provide remote alarm status in a central control facility. The ANSI Standard for a CAAS uses a free-in-air dose rate to define the detection criteria for a minimum accident-of-concern. Previously, the free-in-air absorbed dose rate from neutrons was used for determining the areal coverge of criticality detection within PORTS buildings handling fissile materials. However, the free-in-air dose rate does not accurately reflect the response of the neutron detectors in use at PORTS. Because the cost of placing additional CAAS detectors in areas of questionable coverage (based on a free-in-air absorbed dose rate) is high, the actual response function for the CAAS neutron detectors was determined. This report, which is organized into three major sections, discusses how the actual response function for the PORTS CAAS neutron detectors was determined. The CAAS neutron detectors are described in Section 2. The model of the detector system developed to facilitate calculation of the response function is discussed in Section 3. The results of the calculations, including confirmatory measurements with neutron sources, are given in Section 4

  13. Computational fluid dynamics tracking of UF6 reaction products release into a gaseous diffusion plant cell housing

    International Nuclear Information System (INIS)

    Wendel, M.W.; Chen, N.C.J.; Kim, S.H.; Taleyarkhan, R.P.; Keith, K.D.; Schmidt, R.W.

    1996-01-01

    A three-dimensional (3-D) computational fluid dynamics (CFD) model has been developed using CFDS-FLOW3D Version 3.3 to model the transport of aerosol products formed during a release of uranium hexafluoride (UF 6 ) into a gaseous diffusion plant (GDP) process building. As part of a facility-wide safety evaluation, a one-dimensional (1-D) analysis of aerosol/vapor transport following such an hypothesized severe accident is being performed. The objective of this study is to supplement the 1-D analysis with more detailed 3-D results. Specifically, the goal is to quantify the distribution of aerosol passing out of the process building during the hypothetical accident. This work demonstrates a useful role for CFD in large 3-D problems, where some experimental data are available for calibrating key parameters and the desired results are global (total time-integrated aerosol flow rates across a few boundary surfaces) as opposed to local velocities, temperatures, or heat transfer coefficients

  14. Thermal discharges from Paducah Gaseous Diffusion Plant outfalls: Impacts on stream temperatures and fauna of Little Bayou and Big Bayou Creeks

    Energy Technology Data Exchange (ETDEWEB)

    Roy, W.K.; Ryon, M.G.; Hinzman, R.L. [Oak Ridge National Lab., TN (United States). Computer Science and Mathematics Div.

    1996-03-01

    The development of a biological monitoring plan for the receiving streams of the Paducah Gaseous Diffusion Plant (PGDP) began in the late 1980s, because of an Agreed Order (AO) issued in September 1987 by the Kentucky Division of Water (KDOW). Five years later, in September 1992, more stringent effluent limitations were imposed upon the PGDP operations when the KDOW reissued Kentucky Pollutant Discharge Elimination System permit No. KY 0004049. This action prompted the US Department of Energy (DOE) to request a stay of certain limits contained in the permit. An AO is being negotiated between KDOW, the US Enrichment Corporation (USEC), and DOE that will require that several studies be conducted, including this stream temperature evaluation study, in an effort to establish permit limitations. All issues associated with this AO have been resolved, and the AO is currently being signed by all parties involved. The proposed effluent temperature limit is 89 F (31.7 C) as a mean monthly temperature. In the interim, temperatures are not to exceed 95 F (35 C) as a monthly mean or 100 F (37.8 C) as a daily maximum. This study includes detailed monitoring of instream temperatures, benthic macroinvertebrate communities, fish communities, and a laboratory study of thermal tolerances.

  15. Thermal discharges from Paducah Gaseous Diffusion Plant outfalls: Impacts on stream temperatures and fauna of Little Bayou and Big Bayou Creeks

    International Nuclear Information System (INIS)

    Roy, W.K.; Ryon, M.G.; Hinzman, R.L.

    1996-03-01

    The development of a biological monitoring plan for the receiving streams of the Paducah Gaseous Diffusion Plant (PGDP) began in the late 1980s, because of an Agreed Order (AO) issued in September 1987 by the Kentucky Division of Water (KDOW). Five years later, in September 1992, more stringent effluent limitations were imposed upon the PGDP operations when the KDOW reissued Kentucky Pollutant Discharge Elimination System permit No. KY 0004049. This action prompted the US Department of Energy (DOE) to request a stay of certain limits contained in the permit. An AO is being negotiated between KDOW, the US Enrichment Corporation (USEC), and DOE that will require that several studies be conducted, including this stream temperature evaluation study, in an effort to establish permit limitations. All issues associated with this AO have been resolved, and the AO is currently being signed by all parties involved. The proposed effluent temperature limit is 89 F (31.7 C) as a mean monthly temperature. In the interim, temperatures are not to exceed 95 F (35 C) as a monthly mean or 100 F (37.8 C) as a daily maximum. This study includes detailed monitoring of instream temperatures, benthic macroinvertebrate communities, fish communities, and a laboratory study of thermal tolerances

  16. Thermal Discharges from Paducah Gaseous Diffusion Plant Outfalls: Impacts on Stream Temperatures and Fauna of Little Bayou and Big Bayou Creeks

    International Nuclear Information System (INIS)

    Roy, W.K.

    1999-01-01

    The development of a biological monitoring plan for the receiving streams of the Paducah Gaseous Diffusion Plant (PGDP) began in the late 1980s, because of an Agreed Order (AO) issued in September 1987 by the Kentucky Division of Water (KDOW). Five years later, in September 1992, more stringent effluent limitations were imposed upon the PGDP operations when the KDOW reissued Kentucky Pollutant Discharge Elimination System permit No. KY 0004049. This action prompted the US Department of Energy (DOE) to request a stay of certain limits contained in the permit. An AO is being negotiated between KDOW, the United States Enrichment Corporation (USEC), and DOE that will require that several studies be conducted, including this stream temperature evaluation study, in an effort to establish permit limitations. All issues associated with this AO have been resolved, and the AO is currently being signed by all parties involved. The proposed effluent temperature limit is 89 F (31.7C) as a mean monthly temperature. In the interim, temperatures are not to exceed 95 F (35 C) as a monthly mean or 100 F (37.8 C) as a daily maximum. This study includes detailed monitoring of instream temperatures, benthic macroinvertebrate communities, fish communities, and a laboratory study of thermal tolerances

  17. Thermal Discharges from Paducah Gaseous Diffusion Plant Outfalls: Impacts on Stream Temperatures and Fauna of Little Bayou and Big Bayou Creeks

    Energy Technology Data Exchange (ETDEWEB)

    Roy, W.K.

    1999-01-01

    The development of a biological monitoring plan for the receiving streams of the Paducah Gaseous Diffusion Plant (PGDP) began in the late 1980s, because of an Agreed Order (AO) issued in September 1987 by the Kentucky Division of Water (KDOW). Five years later, in September 1992, more stringent effluent limitations were imposed upon the PGDP operations when the KDOW reissued Kentucky Pollutant Discharge Elimination System permit No. KY 0004049. This action prompted the US Department of Energy (DOE) to request a stay of certain limits contained in the permit. An AO is being negotiated between KDOW, the United States Enrichment Corporation (USEC), and DOE that will require that several studies be conducted, including this stream temperature evaluation study, in an effort to establish permit limitations. All issues associated with this AO have been resolved, and the AO is currently being signed by all parties involved. The proposed effluent temperature limit is 89 F (31.7C) as a mean monthly temperature. In the interim, temperatures are not to exceed 95 F (35 C) as a monthly mean or 100 F (37.8 C) as a daily maximum. This study includes detailed monitoring of instream temperatures, benthic macroinvertebrate communities, fish communities, and a laboratory study of thermal tolerances.

  18. Recycle of radioactive scrap metal from the Oak Ridge Gaseous Diffusion Plant (K-25 Site)

    Energy Technology Data Exchange (ETDEWEB)

    Meehan, R.W. [DOE-Oak Ridge Operations Office, TN (United States)

    1997-02-01

    The scale of the metal available for reuse at the plant includes 22 million pounds of Ni, 17 million pounds of Al, 47 million pounds of copper, and 835 million pounds of steels. In addition there is a wide range of industrial equipment and other items of value. The author describes small bench scale and pilot plant scale efforts made at treating metal for decontamination and fabrication into cast stock or specialized containers for reuse within the DOE complex or release. These projects show that much of the material can be cleaned or chemically decontaminated to a level where it can be free released to various markets. Of the remaining metals, much of it can be cast into products which can be absorbed within the DOE complex.

  19. Reliability study: steam generation and distribution system, Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Baker, F.E.; Davis, E.L.; Dent, J.T.; Walters, D.E.; West, R.M.

    1982-10-01

    A reliability study for determining the ability of the Steam Generation and Distribution System to provide reliable and adequate service through the year 2000 has been completed. This study includes an evaluation of the X-600 Steam Plant and the steam distribution system. The Steam Generation and Distribution System is in good overall condition, but to maintain this condition, the reliability study team made twelve recommendations. Eight of the recommendations are for repair or replacement of existing equipment and have a total estimated cost of $540,000. The other four recommendations are for additional testing, new procedure implementation, or continued investigations

  20. Cooling tower drift studies at the Paducah, Kentucky Gaseous Diffusion Plant

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, F. G.; Hanna, S. R.; Parr, P. D.

    1978-12-01

    The transfer and fate of chromium from cooling tower drift to terrestrial ecosystems were quantified with concentrations in plant materials (fescue grass) decreasing with increasing distance from the cooling tower. Results indicate that elemental content in drift water (mineral residue) may not be equivalent to the content in the recirculating cooling water of the tower. This hypothesis is contrary to basic assumptions in calculating drift emissions. Results suggest that differences in retention in litter and foliage are related to chemical properties of the drift rather than physical lodging of the particle residue. To determine the potential for movement of drift-derived chromium to surface streams, soil-water samplers (wells) were placed along a distance gradient to Little Bayou Creek. Preliminary model estimates of drift deposition are compared to deposition measurements.

  1. DOE enrichment plants-safeguards means business

    International Nuclear Information System (INIS)

    Donnelly, R.

    1987-01-01

    The Portsmouth Gaseous Diffusion Plant, owned by the US Department of Energy (DOE) and operated by Martin Marietta Energy Systems, Inc., is a full service enrichment plant. Its long enriching cascade can process uranium hexafluoride (UF 6 ) feeds at almost any 235 U level and can produce UF 6 over the complete spectrum from depleted to very highly enriched uranium. The DOE uranium enrichment program is a government-owned enterprise operating as a business. The operating concerns of the DOE uranium enrichment plants and their safeguards programs have evolved together over the past three decades, and that evolution will likely continue. As the risk associated with possession, processing, and shipment of strategic nuclear material increased, the protection and control of it increased; as the value of the product grew with time, better ways were found to measure and conserve it. In each of these areas, safeguards objectives and the business requirements of the plant are complementary, and the progress made in one area has been reflected by progress in the other. The plant's material control and accountability program has become crucial to such business requirements as quantifying the enriched uranium (separative work units) produced in each monthly period and convincing financial auditors that the multibillion dollar enriched uranium assets located at the Portsmouth plant are properly stated

  2. COMBINED GEOPHYSICAL INVESTIGATION TECHNIQUES TO IDENTIFY BURIED WASTE IN AN UNCONTROLLED LANDFILL AT THE PADUCAH GASEOUS DIFFUSION PLANT, KENTUCKY

    International Nuclear Information System (INIS)

    Miller, Peter T.; Starmer, R. John

    2003-01-01

    The primary objective of the investigation was to confirm the presence and determine the location of a cache of 30 to 60 buried 55-gallon drums that were allegedly dumped along the course of the pre-existing, northsouth diversion ditch (NSDD) adjacent to permitted landfills at the Paducah Gaseous Diffusion Plant, Kentucky. The ditch had been rerouted and was being filled and re-graded at the time of the alleged dumping. Historic information and interviews with individuals associated with alleged dumping activities indicated that the drums were dumped prior to the addition of other fill materials. In addition, materials alleged to have been dumped in the ditch, such as buried roofing materials, roof flashing, metal pins, tar substances, fly ash, and concrete rubble complicated data interpretation. Some clean fill materials have been placed over the site and graded. This is an environment that is extremely complicated in terms of past waste dumping activities, construction practices and miscellaneous landfill operations. The combination of site knowledge gained from interviews and research of existing site maps, variable frequency EM data, classical total magnetic field data and optimized GPR lead to success where a simpler less focused approach by other investigators using EM-31 and EM-61 electromagnetic methods and unfocused ground penetrating radar (GPR)did not produce results and defined no real anomalies. A variable frequency electromagnetic conductivity unit was used to collect the EM data at 3,030 Hz, 5,070 Hz, 8,430 Hz, and 14,010 Hz. Both in-phase and quadrature components were recorded at each station point. These results provided depth estimates for targets and some information on the subsurface conditions. A standard magnetometer was used to conduct the magnetic survey that showed the locations and extent of buried metal, the approximate volume of ferrous metal present within a particular area, and allowed estimation of approximate target depths. The GPR

  3. TECHNICAL EVALUATION OF TEMPORAL GROUNDWATER MONITORING VARIABILITY IN MW66 AND NEARBY WELLS, PADUCAH GASEOUS DIFFUSION PLANT

    Energy Technology Data Exchange (ETDEWEB)

    Looney, B.; Eddy-Dilek, C.

    2012-08-28

    Evaluation of disposal records, soil data, and spatial/temporal groundwater data from the Paducah Gaseous Diffusion Plant (PGDP) Solid Waste Management Unit (SWMU) 7 indicate that the peak contaminant concentrations measured in monitoring well (MW) 66 result from the influence of the regional PGDP NW Plume, and does not support the presence of significant vertical transport from local contaminant sources in SWMU 7. This updated evaluation supports the 2006 conceptualization which suggested the high and low concentrations in MW66 represent different flow conditions (i.e., local versus regional influences). Incorporation of the additional lines of evidence from data collected since 2006 provide the basis to link high contaminant concentrations in MW66 (peaks) to the regional 'Northwest Plume' and to the upgradient source, specifically, the C400 Building Area. The conceptual model was further refined to demonstrate that groundwater and the various contaminant plumes respond to complex site conditions in predictable ways. This type of conceptualization bounds the expected system behavior and supports development of environmental cleanup strategies, providing a basis to support decisions even if it is not feasible to completely characterize all of the 'complexities' present in the system. We recommend that the site carefully consider the potential impacts to groundwater and contaminant plume migration as they plan and implement onsite production operations, remediation efforts, and reconfiguration activities. For example, this conceptual model suggests that rerouting drainage water, constructing ponds or basin, reconfiguring cooling water systems, capping sites, decommissioning buildings, fixing (or not fixing) water leaks, and other similar actions will potentially have a 'direct' impact on the groundwater contaminant plumes. Our conclusion that the peak concentrations in MW66 are linked to the regional PGDP NW Plume does not imply that

  4. COMBINED GEOPHYSICAL INVESTIGATION TECHNIQUES TO IDENTIFY BURIED WASTE IN AN UNCONTROLLED LANDFILL AT THE PADUCAH GASEOUS DIFFUSION PLANT, KENTUCKY

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Peter T.; Starmer, R. John

    2003-02-27

    The primary objective of the investigation was to confirm the presence and determine the location of a cache of 30 to 60 buried 55-gallon drums that were allegedly dumped along the course of the pre-existing, northsouth diversion ditch (NSDD) adjacent to permitted landfills at the Paducah Gaseous Diffusion Plant, Kentucky. The ditch had been rerouted and was being filled and re-graded at the time of the alleged dumping. Historic information and interviews with individuals associated with alleged dumping activities indicated that the drums were dumped prior to the addition of other fill materials. In addition, materials alleged to have been dumped in the ditch, such as buried roofing materials, roof flashing, metal pins, tar substances, fly ash, and concrete rubble complicated data interpretation. Some clean fill materials have been placed over the site and graded. This is an environment that is extremely complicated in terms of past waste dumping activities, construction practices and miscellaneous landfill operations. The combination of site knowledge gained from interviews and research of existing site maps, variable frequency EM data, classical total magnetic field data and optimized GPR lead to success where a simpler less focused approach by other investigators using EM-31 and EM-61 electromagnetic methods and unfocused ground penetrating radar (GPR)did not produce results and defined no real anomalies. A variable frequency electromagnetic conductivity unit was used to collect the EM data at 3,030 Hz, 5,070 Hz, 8,430 Hz, and 14,010 Hz. Both in-phase and quadrature components were recorded at each station point. These results provided depth estimates for targets and some information on the subsurface conditions. A standard magnetometer was used to conduct the magnetic survey that showed the locations and extent of buried metal, the approximate volume of ferrous metal present within a particular area, and allowed estimation of approximate target depths. The GPR

  5. Investigation of gas-phase decontamination of internally radioactively contaminated gaseous diffusion process equipment and piping

    International Nuclear Information System (INIS)

    Bundy, R.D.; Munday, E.B.

    1991-01-01

    Construction of the gaseous diffusion plants (GDPs) was begun during World War 2 to produce enriched uranium for defense purposes. These plants, which utilized UF 6 gas, were used primarily for this purpose through 1964. From 1959 through 1968, production shifted primarily to uranium enrichment to supply the nuclear power industry. Additional UF 6 -handling facilities were built in feed and fuel-processing plants associated with the uranium enrichment process. Two of the five process buildings at Oak ridge were shut down in 1964. Uranium enrichment activities at Oak Ridge were discontinued altogether in 1985. In 1987, the Department of Energy (DOE) decided to proceed with a permanent shutdown of the Oak Ridge Gaseous Diffusion Plant (ORGDP). DOE intends to begin decommissioning and decontamination (D ampersand D) of ORGDP early in the next century. The remaining two GDPs are expected to be shut down during the next 10 to 40 years and will also require D ampersand D, as will the other UF 6 -handling facilities. This paper presents an investigation of gas- phase decontamination of internally radioactively contaminated gaseous diffusion process equipment and piping using powerful fluorinating reagents that convert nonvolatile uranium compounds to volatile UF 6 . These reagents include ClF 3 , F 2 , and other compounds. The scope of D ampersand D at the GDPs, previous work of gas-phase decontamination, four concepts for using gas-phase decontamination, plans for further study of gas-phase decontamination, and the current status of this work are discussed. 13 refs., 15 figs

  6. Correlation and prediction of gaseous diffusion coefficients.

    Science.gov (United States)

    Marrero, T. R.; Mason, E. A.

    1973-01-01

    A new correlation method for binary gaseous diffusion coefficients from very low temperatures to 10,000 K is proposed based on an extended principle of corresponding states, and having greater range and accuracy than previous correlations. There are two correlation parameters that are related to other physical quantities and that are predictable in the absence of diffusion measurements. Quantum effects and composition dependence are included, but high-pressure effects are not. The results are directly applicable to multicomponent mixtures.

  7. NRC licensing of uranium enrichment plants

    International Nuclear Information System (INIS)

    Moran, B.W.

    1991-01-01

    The US Nuclear Regulatory Commission (NRC) is preparing a rule making that establishes the licensing requirements for low-enriched uranium enrichment plants. Although implementation of this rule making is timed to correspond with receipt of a license application for the Louisiana Energy Services centrifuge enrichment plant, the rule making is applicable to all uranium enrichment technologies. If ownership of the US gaseous diffusion plants and/or atomic vapor laser isotope separation is transferred to a private or government corporation, these plants also would be licensable under the new rule making. The Safeguards Studies Department was tasked by the NRC to provide technical assistance in support of the rule making and guidance preparation process. The initial and primary effort of this task involved the characterization of the potential safeguards concerns associated with a commercial enrichment plant, and the licensing issues associated with these concerns. The primary safeguards considerations were identified as detection of the loss of special nuclear material, detection of unauthorized production of material of low strategic significance, and detection of production of uranium enriched to >10% 235 U. The primary safeguards concerns identified were (1) large absolute limit of error associated with the material balance closing, (2) the inability to shutdown some technologies to perform a cleanout inventory of the process system, and (3) the flexibility of some technologies to produce higher enrichments. Unauthorized production scenarios were identified for some technologies that could prevent conventional material control and accounting programs from detecting the production and removal of 5 kg 235 U as highly enriched uranium. Safeguards techniques were identified to mitigate these concerns

  8. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Paducah Gaseous Diffusion Plant site

    Energy Technology Data Exchange (ETDEWEB)

    Marmer, G.J.; Dunn, C.P.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Yuen, C.R.; Cleland, J.H. (ed.)

    1991-09-01

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. The U-235 atoms are ionized when precisely tuned laser light -- of appropriate power, spectral, and temporal characteristics -- illuminates the uranium vapor and selectively photoionizes the U-235 isotope. A programmatic document for use in screening DOE site to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the PGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. 65 refs., 15 tabs.

  9. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Paducah Gaseous Diffusion Plant site

    International Nuclear Information System (INIS)

    Marmer, G.J.; Dunn, C.P.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Yuen, C.R.; Cleland, J.H.

    1991-09-01

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. The U-235 atoms are ionized when precisely tuned laser light -- of appropriate power, spectral, and temporal characteristics -- illuminates the uranium vapor and selectively photoionizes the U-235 isotope. A programmatic document for use in screening DOE site to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the PGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. 65 refs., 15 tabs

  10. EURODIF company - Tricastin gaseous diffusion plant. Requests following the safety re-evaluation of the facility after 20 years of operation

    International Nuclear Information System (INIS)

    2000-01-01

    This decision from the French authority of nuclear safety (ASN) concerns the safety reevaluation of the EURODIF plant ('Georges Besse plant') of the Tricastin site at Pierrelatte (France) which uses the gaseous diffusion process to separate the uranium isotopes. Since the last safety reevaluation in 1988, several points have been improved: reduction of the frequency and importance of uranium hexafluoride leaks (control of the pitting corrosion in the exchangers), no incident linked with exo-thermal reactions or explosions, a mastery of the exposure to ionizing radiations etc.. On the other hand, several points need improvement: the prevention of criticality risks, the earthquake resistance of some structures, and the integration of some accident scenarios (aircraft crash, UF 6 leak) in the emergency plan to avoid the fast release of toxic materials in the environment. These points are detailed in the document. (J.S.)

  11. Potential Hazards Relating to Pyrolysis of c-C4F8O, n-C4F10 and c-C4F8 in selected gaseous diffusion plant operations

    International Nuclear Information System (INIS)

    Trowbridge, L.D.

    2000-01-01

    As part of a program intended to replace the present evaporative coolant at the gaseous diffusion plants (GDPs) with a non-ozone-depleting alternate, a series of investigations of the suitability of candidate substitutes is under way. This report summarizes studies directed at estimating the chemical and thermal stability of three candidate coolants, c-C 4 F 8 O, n-C 4 F 10 and c-C 4 4F 8 , in a few specific environments to be found in gaseous diffusion plant operations

  12. Field evaluation of a horizontal well recirculation system for groundwater treatment: Pilot test at the Clean Test Site Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    International Nuclear Information System (INIS)

    Muck, M.T.; Kearl, P.M.; Siegrist, R.L.

    1998-01-01

    This report presents the results of field testing a horizontal well recirculation system at the Portsmouth Gaseous Diffusion Plant (PORTS). The recirculation system uses a pair of horizontal wells, one for groundwater extraction and treatment and the other for reinjection of treated groundwater, to set up a recirculation flow field. The induced flow field from the injection well to the extraction well establishes a sweeping action for the removal and treatment of groundwater contaminants. The overall purpose of this project is to study treatment of mixed groundwater contaminants that occur in a thin water-bearing zone not easily targeted by traditional vertical wells. The project involves several research elements, including treatment-process evaluation, hydrodynamic flow and transport modeling, pilot testing at an uncontaminated site, and pilot testing at a contaminated site. The results of the pilot test at an uncontaminated site, the Clean Test Site (CTS), are presented in this report

  13. Environmental investigations at the Paducah Gaseous Diffusion Plant and surrounding area, McCracken County, Kentucky. Volume 1 - Executive summary. Final report

    International Nuclear Information System (INIS)

    1994-05-01

    This report details the results of four studies into environmental and cultural resources on and near the Department of Energy's (DOE) Paducah Gaseous Diffusion Plant (PGDP) located in Western Kentucky in McCracken County, approximately 10 miles west of Paducah, KY. The area investigated includes the PGDP facility proper, additional area owned by DOE under use permit to the Western Kentucky Wildlife Management Area (WKWMA), area owned by the Commonwealth of Kentucky that is administered by the WKWMA, area owned by the Tennessee Valley Authority (TVA), the Metropolis Lake State Nature preserve and some privately held land. DOE requested the assistance and support of the US Army Engineer District, Nashville (CEORN) in conducting various environmental investigations of the area. The US Army Engineer Waterways Experiment Station (WES) provided technical support to the CEORN for environmental investigations of (1) wetland resources, (2) threatened or endangered species and habitats, and (3) cultural resources. A floodplain investigation was conducted by CEORN

  14. Assessment of the influences of groundwater colloids on the migration of technetium-99 at the Paducah Gaseous Diffusion Plant Site in Paducah, Kentucky

    International Nuclear Information System (INIS)

    Gu, B.; McDonald, J.A.; McCarthy, J.F.; Clausen, J.L.

    1994-07-01

    This short report summarizes the influences of groundwater colloids on the migration/transport of 99 Tc at the Paducah Gaseous Diffusion Plant (PGDP) site in Paducah, Kentucky. Limited data suggest that inorganic colloidal materials (e.g., aluminosilicate clay minerals) may not play a significant role in the retention and transport of Tc. Studies by size fractionation reveal that both Tc and natural organic matter (NOM) are largely present in the -8 mol/L or parts per billion), regardless of the redox conditions, Tc will stay in solution phase as TC(IV) or Tc(VII). The mechanisms of adsorption/association vs precipitation must be understood under reduced and low Tc conditions so that strategic plans for remediation of Tc contaminated soils and groundwaters can be developed

  15. Non-destructive measurement methods for large scale gaseous diffusion process equipment

    International Nuclear Information System (INIS)

    Mayer, R.L.; Hagenauer, R.C.; McGinnis, B.R.

    1994-01-01

    Two measurement methods have been developed to measure non-destructively uranium hold-up in gaseous diffusion plants. These methods include passive neutron and passive γ ray measurements. An additional method, high resolution γ ray spectroscopy, provides supplementary information about additional γ ray emitting isotopes, γ ray correction factors, 235 U/ 234 U ratios and 235 U enrichment. Many of these methods can be used as a general purpose measurement technique for large containers of uranium. Measurement applications for these methods include uranium hold-up, waste measurements, criticality safety and nuclear accountability

  16. Refurbishment of uranium hexafluoride cylinder storage yards C-745-K, L, M, N, and P and construction of a new uranium hexafluoride cylinder storage yard (C-745-T) at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    International Nuclear Information System (INIS)

    1996-07-01

    The Paducah Gaseous Diffusion Plant (PGDP) is a uranium enrichment facility owned by the US Department of Energy (DOE). A residual of the uranium enrichment process is depleted uranium hexafluoride (UF6). Depleted UF6, a solid at ambient temperature, is stored in 32,200 steel cylinders that hold a maximum of 14 tons each. Storage conditions are suboptimal and have resulted in accelerated corrosion of cylinders, increasing the potential for a release of hazardous substances. Consequently, the DOE is proposing refurbishment of certain existing yards and construction of a new storage yard. This environmental assessment (EA) evaluates the impacts of the proposed action and no action and considers alternate sites for the proposed new storage yard. The proposed action includes (1) renovating five existing cylinder yards; (2) constructing a new UF6 storage yard; handling and onsite transport of cylinders among existing yards to accommodate construction; and (4) after refurbishment and construction, restacking of cylinders to meet spacing and inspection requirements. Based on the results of the analysis reported in the EA, DOE has determined that the proposed action is not a major Federal action that would significantly affect the quality of the human environment within the context of the National Environmental Policy Act of 1969. Therefore, DOE is issuing a Finding of No Significant Impact. Additionally, it is reported in this EA that the loss of less than one acre of wetlands at the proposed project site would not be a significant adverse impact

  17. Refurbishment of uranium hexafluoride cylinder storage yards C-745-K, L, M, N, and P and construction of a new uranium hexafluoride cylinder storage yard (C-745-T) at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    The Paducah Gaseous Diffusion Plant (PGDP) is a uranium enrichment facility owned by the US Department of Energy (DOE). A residual of the uranium enrichment process is depleted uranium hexafluoride (UF6). Depleted UF6, a solid at ambient temperature, is stored in 32,200 steel cylinders that hold a maximum of 14 tons each. Storage conditions are suboptimal and have resulted in accelerated corrosion of cylinders, increasing the potential for a release of hazardous substances. Consequently, the DOE is proposing refurbishment of certain existing yards and construction of a new storage yard. This environmental assessment (EA) evaluates the impacts of the proposed action and no action and considers alternate sites for the proposed new storage yard. The proposed action includes (1) renovating five existing cylinder yards; (2) constructing a new UF6 storage yard; handling and onsite transport of cylinders among existing yards to accommodate construction; and (4) after refurbishment and construction, restacking of cylinders to meet spacing and inspection requirements. Based on the results of the analysis reported in the EA, DOE has determined that the proposed action is not a major Federal action that would significantly affect the quality of the human environment within the context of the National Environmental Policy Act of 1969. Therefore, DOE is issuing a Finding of No Significant Impact. Additionally, it is reported in this EA that the loss of less than one acre of wetlands at the proposed project site would not be a significant adverse impact.

  18. Applicable or relevant and appropriate requirements (ARARs) for remedial actions at the Paducah Gaseous Diffusion Plant: A compendium of environmental laws and guidance

    International Nuclear Information System (INIS)

    Etnier, E.L.; Eaton, L.A.

    1992-03-01

    Section 121 of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980 specifies that remedial actions for cleanup of hazardous substances found at sites placed on the National Priorities List (NPL) by the US Environmental Protection Agency (EPA) must comply with applicable or relevant and appropriate requirements (ARARs) or standards under federal and state environmental laws. To date, the US Department of Energy (DOE) Paducah Gaseous Diffusion Plant (PGDP) has not been on the NPL. Although DOE and EPA have entered into an Administrative Consent Order (ACO), the prime regulatory authority for cleanup at PGDP will be the Resource Conservation and Recovery Act (RCRA). This report supplies a preliminary list of available federal and state ARARs that might be considered for remedial response at PGDP in the event that the plant becomes included on the NPL or the ACO is modified to include CERCLA cleanup. A description of the terms ''applicable'' and ''relevant and appropriate'' is provided, as well as definitions of chemical-, location-, and action-specific ARARS. ARARs promulgated by the federal government and by the state of Kentucky are listed in tables. In addition, the major provisions of RCRA, the Safe Drinking Water Act, the Clean Water Act, the Clean Air Act, and other acts, as they apply to hazardous and radioactive waste cleanup, are discussed

  19. Uranium enrichment. 1980 annual report

    International Nuclear Information System (INIS)

    1981-05-01

    This report contains data and related information on the production of enriched uranium at the gaseous diffusion plants and an update on the construction and project control center for the gas centrifuge plant. Power usage at the gaseous diffusion plants is illustrated. The report contains several glossy color pictures of the plants and processes described. In addition to gaseous diffusion and the centrifuge process, three advanced isotope separation process are now being developed. The business operation of the enrichment plants is described; charts on revenue, balance sheets, and income statements are included

  20. Isotope enrichment effect of gaseous mixtures in standing sound vibration

    International Nuclear Information System (INIS)

    Knesebeck, R.L.

    1984-01-01

    When standing acoustic waves are excited in a tube containing a mixture of two gases, a partial zonal fractioning of the components arises as consequence of mass transport by diffusion, driven by the thermal and pressure gradients which are associeted with the standing waves. This effect is present in each zone corresponding to a quarter wavelength, with the heavier component becoming enriched at the nodes fo the standing waves and deplected at the crests. The magnitude of the enrichment in one of the components of a binary gas mixture is given by Δω=ap 2 /lambda [b + (1-bω)] 2 . Where ω is the mass concentration of the component in the mixture, a and b are parameters which are related to molecular proprieties of the gases, p is the relative pressure amplitude of the standing wave and lambda is its wavelength. For a natural mixture of uranium hexafluorate, with 0.715% of the uranium isotope 340 an enrichment of about 2 x 10 -6 % in the concentration of this isotope is theorecticaly attainable per stage consisting of a quarter wavelenght, when a standing acoustical wave of relative pressure amplitude of 0,2 and wavelenght of 20 cm is used. Since standing acoustical waves are easely excited in gas columns, an isotope enrichment plant made of a cascade of tubes in which standing waves are excited, is presumably feasible with relatively low investment and operation costs. (Author) [pt

  1. Computer-optimized γ-NDA geometries for uranium enrichment verification of gaseous UF6

    International Nuclear Information System (INIS)

    Wichers, V.A.; Aaldijk, J.K.; Betue, P.A.C. de; Harry, R.J.S.

    1993-05-01

    An improved collimator pair of novel design tailored for deposit independent enrichment verification of gaseous UF 6 at low pressures in cascade-to-header pipes of small diameters in centrifuge enrichment plants is presented. The designs are adapted for use in a dual-geometry arrangement for simultaneous measurements with both detection geometries. The average measurement time with the dual-geometry arrangement is approximately half an hour for deposit-to-gas activity ratios as high as 20. (orig.)

  2. Stable isotope enrichment by thermal diffusion

    International Nuclear Information System (INIS)

    Vasaru, Gheorghe

    2003-01-01

    Thermal diffusion (TD) in both gaseous and liquid phase has been the subject of extensive experimental and theoretical investigations, especially after the invention by K. Clusius and G. Dickel of the thermal diffusion column, sixty years ago. This paper gives a brief overview of the most important applications and developments of this transport phenomenon for enrichment of 13 C and of some noble gases isotopes in our institute. The results of calculations of the transport coefficients H and K for a concentric tube type TD column, operated with methane as process gas, are presented. Static separation factor at equilibrium vs gas pressure has been calculated for various molecular models. The experimental separation factors for different gas pressure were found to be consistent with those calculated for the inverse power repulsion model and the Lennard-Jones model. The most important characteristics of a seven-stage cascade consisting of 19 TD columns of concentric tube type are given. This system has been constructed and successfully operated at a temperature of 673 K and produces an enrichment of methane of natural isotopic 13 C abundance, up to the concentration of 25% 13 CH 4 . Enrichment of the noble gases isotopes implies: - a . Enrichment of 20 Ne and 22 Ne in a eight-stage cascade consisting of 8 TD columns; - b. enrichment of 46 Ar in a seven-stage cascade consisting of TD columns and finally; - c. enrichment of 78 Kr and 86 Kr in a fifteen-stage cascade, consisting of 35 TD columns. For all these installations we have adopted TD columns of hot wire type (4 m in length), operated at a temperature of 1073 K. (author)

  3. Field evaluation of a horizontal well recirculation system for groundwater treatment: Field demonstration at X-701B Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    Energy Technology Data Exchange (ETDEWEB)

    Korte, N.; Muck, M.; Kearl, P.; Siegrist, R.; Schlosser, R.; Zutman, J. [Oak Ridge National Lab., TN (United States); Houk, T. [Lockheed Martin Energy Systems, Piketon, OH (United States). Portsmouth Gaseous Diffusion Plant

    1998-08-01

    This report describes the field-scale demonstration performed as part of the project, In Situ Treatment of Mixed Contaminants in Groundwater. This project was a 3{1/2} year effort comprised of laboratory work performed at Oak Ridge National Laboratory and fieldwork performed at the US Department of Energy (DOE) Portsmouth Gaseous Diffusion Plant (PORTS). The overall goal of the project was to evaluate in situ treatment of groundwater using horizontal recirculation coupled with treatment modules. Specifically, horizontal recirculation was tested because of its application to thin, interbedded aquifer zones. Mixed contaminants were targeted because of their prominence at DOE sites and because they cannot be treated with conventional methods. The project involved several research elements, including treatment process evaluation, hydrodynamic flow and transport modeling, pilot testing at an uncontaminated site, and full-scale testing at a contaminated site. This report presents the results of the work at the contaminated site, X-701B at PORTS. Groundwater contamination at X-701B consists of trichloroethene (TCE) (concentrations up to 1800 mg/L) and technetium-998 (Tc{sup 99}) (activities up to 926 pCi/L).

  4. Dual wall reverse circulation drilling with multi-level groundwater sampling for groundwater contaminant plume delineation at Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    International Nuclear Information System (INIS)

    Smuin, D.R.; Morti, E.E.; Zutman, J.L.; Pickering, D.A.

    1995-01-01

    Dual wall reverse circulation (DWRC) drilling was used to drill 48 borings during a groundwater contaminant investigation at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky. This method was selected as an alternative to conventional hollow stem auger drilling for a number of reasons, including the expectation of minimizing waste, increasing the drilling rate, and reducing the potential for cross contamination of aquifers. Groundwater samples were collected from several water-bearing zones during drilling of each borehole. The samples were analyzed for volatile organic compounds using a field gas chromatograph. This approach allowed the investigation to be directed using near-real-time data. Use of downhole geophysical logging, in conjunction with lithologic descriptions of borehole cuttings, resulted in excellent correlation of the geology in the vicinity of the contaminant plume. The total volume of cuttings generated using the DWRC drilling method was less than half of what would have been produced by hollow stem augering; however, the cuttings were recovered in slurry form and had to be dewatered prior to disposal. The drilling rate was very rapid, often approaching 10 ft/min; however, frequent breaks to perform groundwater sampling resulted in an average drilling rate of < 1 ft/min. The time required for groundwater sampling could be shortened by changing the sampling methodology. Analytical results indicated that the drilling method successfully isolated the various water bearing zones and no cross contamination resulted from the investigation

  5. Field evaluation of a horizontal well recirculation system for groundwater treatment: Field demonstration at X-701B Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    International Nuclear Information System (INIS)

    Korte, N.; Muck, M.; Kearl, P.; Siegrist, R.; Schlosser, R.; Zutman, J.; Houk, T.

    1998-01-01

    This report describes the field-scale demonstration performed as part of the project, In Situ Treatment of Mixed Contaminants in Groundwater. This project was a 3 1/2 year effort comprised of laboratory work performed at Oak Ridge National Laboratory and fieldwork performed at the US Department of Energy (DOE) Portsmouth Gaseous Diffusion Plant (PORTS). The overall goal of the project was to evaluate in situ treatment of groundwater using horizontal recirculation coupled with treatment modules. Specifically, horizontal recirculation was tested because of its application to thin, interbedded aquifer zones. Mixed contaminants were targeted because of their prominence at DOE sites and because they cannot be treated with conventional methods. The project involved several research elements, including treatment process evaluation, hydrodynamic flow and transport modeling, pilot testing at an uncontaminated site, and full-scale testing at a contaminated site. This report presents the results of the work at the contaminated site, X-701B at PORTS. Groundwater contamination at X-701B consists of trichloroethene (TCE) (concentrations up to 1800 mg/L) and technetium-998 (Tc 99 ) (activities up to 926 pCi/L)

  6. Application of the electromagnetic borehole flowmeter and evaluation of previous pumping tests at Paducah Gaseous Diffusion Plant. Final report, June 15, 1992--August 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Young, S.C.; Julian, S.C.; Neton, M.J.

    1993-01-01

    Multi-well pumping tests have been concluded at wells MW79, MW108, and PW1 at the Paducah Gaseous Diffusion Plant (PGDP) to determine the hydraulic properties of the Regional Gravel Aquifer (RGA). Soil cores suggest that the RGA consists of a thin sandy facies (2 to 6 feet) at the top of a thicker (> 10 feet) gravelly facies. Previous analyses have not considered any permeability contrast between the two facies. To assess the accuracy of this assumption, TVA personnel conducted borehole flowmeter tests at wells MW108 and PW1. Well MW79 could not be tested. The high K sand unit is probably 10 times more permeable than comparable zone in the gravelly portion of the RGA. Previous analyses of the three multi-well aquifer tests do not use the same conceptual aquifer model. Data analysis for one pumping test assumed that leakance was significant. Data analysis for another pumping test assumed that a geologic boundary was significant. By collectively analyzing all three tests with the borehole flowmeter results, the inconsistency among the three pumping tests can be explained. Disparity exists because each pumping test had a different placement of observation wells relative to the high K zone delineating by flowmeter testing.

  7. Increased Suicide Risk among Workers following Toxic Metal Exposure at the Paducah Gaseous Diffusion Plant From 1952 to 2003: A Cohort Study

    Directory of Open Access Journals (Sweden)

    LW Figgs

    2011-09-01

    Full Text Available Background: Suicide is a problem worldwide and occupation is an important risk factor. In the last decade, 55 200 deaths in the US were attributed to occupational risk factors. Objective: To determine if toxic metal exposure was associated with suicide risk among Paducah gaseous diffusion plant (PGDP workers. Methods: We assembled a cohort of 6820 nuclear industry workers employed from 1952 to 2003. A job-specific exposure matrix (JEM was used to determine metal exposure likelihood. Uranium exposure was also assessed by urinalysis. All suicide/self-injury International Classification for Disease (ICD codes were used to identify suicides. Standardized mortality ratios (SMR, odds ratios (OR, and hazard ratios (HR were used to estimate suicide risk. Results: PGDP suicide victims typically were younger white men. Within exposure likelihood categories, several suicide SMRs were typically elevated for several metals. Only beryllium exposure likelihood was associated with an increased HR. Uranium urine concentration was associated with an elevated suicide risk after stratification by urinalysis frequency. Conclusion: Suicide risk is associated with uranium exposure.

  8. Applicable or relevant and appropriate requirements (ARARs) for remedial actions at the Portsmouth Gaseous Diffusion Plant: A compendium of environmental laws and guidance

    International Nuclear Information System (INIS)

    Houlberg, L.M.; Eaton, L.A.; Martin, J.A.; McDonald, E.P.; Etnier, E.L.

    1992-02-01

    Section 121 of the Comprehensive Environmental Response, Compensation, and Liability Act of 1990 (CERCLA) specifies that remedial actions for cleanup of hazardous substances must comply with applicable or relevant and appropriate requirements (ARARs) or standards under federal and state environmental laws. Although the US Department of Energy (DOE) Portsmouth Gaseous Diffusion Plant (PORTS) has not at this time been proposed for inclusion on the US Environmental Protection Agency National Priorities List, under Sect. I of an administrative consent order signed by DOE and the US Environmental Protection Agency on September 29, 1989, effective October 4, 1989, any necessary response actions at PORTS stipulated in the administrative consent order must be performed in a manner consistent with the Resource Conservation and Recovery Act of 1976 and CERCLA. Section 121 of CERCLA calls for the preparation of a draft listing of all ARARs. This report supplies a preliminary list of available federal and state ARARs that might be considered for remedial response at PORTS. A description of the terms ''applicable'' and ''relevant and appropriate'' is provided, as well as definitions of chemical-, location-, and action-specific ARARs. ARARs promulgated by the federal government and by the state of Ohio are listed in tables. In addition, the major provisions of the Resource Conservation and Recovery Act, Safe Drinking Water Act, Clean Water Act, and other acts, as they apply to hazardous waste cleanup, are discussed

  9. Modification and expansion of X-7725A Waste Accountability Facility for storage of polychlorinated biphenyl wastes at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    International Nuclear Information System (INIS)

    1995-11-01

    The US Department of Energy (DOE) must manage wastes containing polychlorinated biphenyls (PCBs) in accordance with Toxic Substances Control Act (TSCA) requirements and as prescribed in a Federal Facilities Compliance Agreement (FFCA) between DOE and the U.S. Environmental Protection Agency (EPA). PCB-containing wastes are currently stored in the PORTS process buildings where they are generated. DOE proposes to modify and expand the Waste Accountability facility (X-7725A) at the Portsmouth Gaseous Diffusion Plant (PORTS), Piketon, Ohio, to provide a central storage location for these wastes. The proposed action is needed to eliminate the fire and safety hazards presented by the wastes. In this EA, DOE considers four alternatives: (1) no action, which requires storing wastes in limited storage areas in existing facilities; (2) modifying and expanding the X-7725A waste accountability facility; (3) constructing a new PCB waste storage building; and (4) shipping PCB wastes to the K-25 TSCA incinerator. If no action is taken, PCB-contaminated would continue to be stored in Bldgs X-326, X-330, and X-333. As TSCA cleanup activities continue, the quantity of stored waste would increase, which would subsequently cause congestion in the three process buildings and increase fire and safety hazards. The preferred alternative is to modify and expand Bldg. X-7725A to store wastes generated by TSCA compliance activities. Construction, which could begin as early as April 1996, would last approximately five to seven months, with a total peak work force of 70

  10. Potential Hazards Relating to Pyrolysis of c-C{sub 4}F{sub 8} in Selected Gaseous Diffusion Plant Operations

    Energy Technology Data Exchange (ETDEWEB)

    Trowbridge, L.D.

    1999-03-01

    As part of a program intended to replace the present evaporative coolant at the gaseous diffusion plants (GDPs) with a non-ozone-depleting alternate, a series of investigations of the suitability of candidate substitutes in under way. One issue concerning a primary candidate, c-C4F8, is the possibility that it might produce the highly toxic perfluoroisobutylene (PFIB) in high temperature environments. This study was commissioned to determine the likelihood and severity of decomposition under two specific high temperature thermal environments, namely the use of a flame test for the presence of coolant vapors and welding in the presence of coolant vapors. The purpose of the study was to develop and evaluate available data to provide information that will allow the technical and industrial hygiene staff at the GDPs to perform appropriate safety evaluations and to determine the need for field testing or experimental work. The scope of this study included a literature search and an evaluation of the information developed therefrom. Part of that evaluation consists of chemical kinetics modeling of coolant decomposition in the two operational environments. The general conclusions are that PFIB formation is unlikely in either situation but that it cannot be ruled out completely under extreme conditions. The presence of oxygen, moisture, and combustion products will tend to lead to formation of oxidation products (COF2, CO, CO2, and HF) rather than PFIB.

  11. Gas phase decontamination of gaseous diffusion process equipment

    International Nuclear Information System (INIS)

    Bundy, R.D.; Munday, E.B.; Simmons, D.W.; Neiswander, D.W.

    1994-01-01

    D ampersand D of the process facilities at the gaseous diffusion plants (GDPs) will be an enormous task. The EBASCO estimate places the cost of D ampersand D of the GDP at the K-25 Site at approximately $7.5 billion. Of this sum, nearly $4 billion is associated with the construction and operation of decontamination facilities and the dismantlement and transport of contaminated process equipment to these facilities. In situ long-term low-temperature (LTLT) gas phase decontamination is being developed and demonstrated at the K-25 site as a technology that has the potential to substantially lower these costs while reducing criticality and safeguards concerns and worker exposure to hazardous and radioactive materials. The objective of gas phase decontamination is to employ a gaseous reagent to fluorinate nonvolatile uranium deposits to form volatile LJF6, which can be recovered by chemical trapping or freezing. The LTLT process permits the decontamination of the inside of gas-tight GDP process equipment at room temperature by substituting a long exposure to subatmospheric C1F for higher reaction rates at higher temperatures. This paper outlines the concept for applying LTLT gas phase decontamination, reports encouraging laboratory experiments, and presents the status of the design of a prototype mobile system. Plans for demonstrating the LTLT process on full-size gaseous diffusion equipment are also outlined briefly

  12. Second order transient effects in a gaseous diffusion plant; Effets transitoires du second ordre dans une installation de separation isotopique

    Energy Technology Data Exchange (ETDEWEB)

    Bouligand, O M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    Perturbations applied to various parameters of an isotope separation plant indices an average effect on production. This effect is determined for a finite cascade over infinite reservoir. Perturbations on product flow rate and inter-stage transports are considered. (author) [French] Les fluctuations des divers parametres d'une installation de separation isotopique alterent la moyenne temporelle de la concentration du produit enrichi, Cet effet peut etre calcule dans le cas d'une cascade constante alimentee a sa base par un reservoir infini pour des fluctuations qui affectent les capacites des etages et le debit de production. (auteur)

  13. Environmental surveillance of the US Department of Energy Portsmouth Gaseous Diffusion Plant and surrounding environs during 1986: Volume 4

    International Nuclear Information System (INIS)

    Oakes, T.W.; Wiehle, W.E.; Valentine, B.L.

    1987-04-01

    This report provides monitoring data for the installation and surrounding environs that may have been affected by operations on the plant site; provides detailed information about the installation; provides detailed information on input and assumption used in all calculations; integrates monitoring data and related studies in one document to pull together, highlight, and summarize the information contained in many documents; provides trend analyses, where possible, to indicate increases and decreases in environmental conditions; and provides general information on the plant site and quality assurance. Routine monitoring and sampling for radiation, radioactive materials, and chemical substances on and off the DOE reservation and PORTS are used to document compliance with appropriate standards, identify trends, provide information for the public, and contribute to general environmental knowledge. The surveillance program assists in fulfilling the DOE policy of protecting the public, employees, and the environment from harm that could be caused by its activities and reducing negative environmental impacts to the greatest degree practicable. Environmental monitoring information complements data on specific releases, trends, and summaries. 68 refs., 203 figs., 112 tabs

  14. The new enrichment plant of AREVA, a worthy heir of Georges Besse's industrial visions

    International Nuclear Information System (INIS)

    Oursel, L.

    2011-01-01

    The Georges Besse II enrichment plant was inaugurated on December 14., 2010. This plant was the most important investment in France during the last decade, about 3 billion euros. This plant is based on the centrifugation technology instead of the gaseous diffusion that is still in operation in the Georges Besse plant of EURODIF. This plant has been designed in an environment-friendly approach: the centrifugation technology uses 50 times less electricity than gaseous diffusion, does not require taking water from the Rhone river for cooling, does not produce sound nuisances, and the moderate height of the buildings allows a better integration in the environment. The low amount of matter involved in the centrifugation process gives the plant a high level of safety. The plant has a capacity of 7.5 millions UTS with a possible extension to 11 millions UTS. (A.C.)

  15. Nuclear criticality safety aspects of gaseous uranium hexafluoride (UF{sub 6}) in the diffusion cascade

    Energy Technology Data Exchange (ETDEWEB)

    Huffer, J.E. [Parallax, Inc., Atlanta, GA (United States)

    1997-04-01

    This paper determines the nuclear safety of gaseous UF{sub 6} in the current Gaseous Diffusion Cascade and auxiliary systems. The actual plant safety system settings for pressure trip points are used to determine the maximum amount of HF moderation in the process gas, as well as the corresponding atomic number densities. These inputs are used in KENO V.a criticality safety models which are sized to the actual plant equipment. The ENO V.a calculation results confirm nuclear safety of gaseous UF{sub 6} in plant operations..

  16. Nuclear criticality safety aspects of gaseous uranium hexafluoride (UF6) in the diffusion cascade

    International Nuclear Information System (INIS)

    Huffer, J.E.

    1997-04-01

    This paper determines the nuclear safety of gaseous UF 6 in the current Gaseous Diffusion Cascade and auxiliary systems. The actual plant safety system settings for pressure trip points are used to determine the maximum amount of HF moderation in the process gas, as well as the corresponding atomic number densities. These inputs are used in KENO V.a criticality safety models which are sized to the actual plant equipment. The ENO V.a calculation results confirm nuclear safety of gaseous UF 6 in plant operations

  17. Feasibility of nondestructive assay measurements in uranium enrichment plants

    Energy Technology Data Exchange (ETDEWEB)

    Walton, R.B.

    1978-04-01

    Applications of nondestructive assay methods to measurement problems in uranium enrichment facilities are reviewed. The results of a number of test and evaluation projects that were performed over the last decade at ORGDP and Portsmouth are presented. Measurements of the residual holdup in the top enrichment portion of the shut-down K-25 cascade were made with portable neutron and gamma-ray detectors, and inventory estimates based on these data were in good agreement with ORGDP estimates. In the operating cascade, the tests showed that portable NaI detectors are effective for monitoring NaF and alumina media for gaseous effluent traps and that gas phase enrichments and inventories, as well as large deposits of uranium, can be detected with portable neutron and gamma-ray instrumentation. A wide variety of scrap and waste materials, including barrier and compressor blades, incinerator ash and trapping media, and miscellaneous waste, were measured using passive gamma-ray and neutron methods and 14-MeV neutron interrogation. Methods developed for rapid verification of UF/sub 6/ in shipping containers with portable neutron and gamma-ray instruments are now used routinely by safeguards inspectors. Passive assay methods can also be used to measure continuously the enrichments of /sup 235/U and /sup 234/U in the UF/sub 6/ product and tails withdrawals of a gaseous diffusion plant. A system that was developed and installed in the extended-range product withdrawal station of the Portsmouth facility measures enrichment with a relative accuracy of 0.5%. A stand-alone neutron detector has also been successfully evaluated for the measurement of the isotopic abundance of /sup 234/U in UF/sub 6/ in sample cylinders, an application of potential importance to Minor Isotope Safeguards Technology. Recommendations are made on the role of NDA measurements for enrichment plant safeguards, including additional tests and evaluations that may be needed, particularly for advanced uranium

  18. Dose Modeling Evaluations and Technical Support Document For the Authorized Limits Request for the DOE-Owned Property Outside the Limited Area, Paducah Gaseous Diffusion Plant Paducah, Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    Boerner, A. J. [Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN (United States). Independent Environmental Assessment and Verification Program; Maldonado, D. G. [Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN (United States). Independent Environmental Assessment and Verification Program; Hansen, Tom [Ameriphysics, LLC (United States)

    2012-09-01

    Environmental assessments and remediation activities are being conducted by the U.S. Department of Energy (DOE) at the Paducah Gaseous Diffusion Plant (PGDP), Paducah, Kentucky. The Oak Ridge Institute for Science and Education (ORISE), a DOE prime contractor, was contracted by the DOE Portsmouth/Paducah Project Office (DOE-PPPO) to conduct radiation dose modeling analyses and derive single radionuclide soil guidelines (soil guidelines) in support of the derivation of Authorized Limits (ALs) for 'DOE-Owned Property Outside the Limited Area' ('Property') at the PGDP. The ORISE evaluation specifically included the area identified by DOE restricted area postings (public use access restrictions) and areas licensed by DOE to the West Kentucky Wildlife Management Area (WKWMA). The licensed areas are available without restriction to the general public for a variety of (primarily) recreational uses. Relevant receptors impacting current and reasonably anticipated future use activities were evaluated. In support of soil guideline derivation, a Conceptual Site Model (CSM) was developed. The CSM listed radiation and contamination sources, release mechanisms, transport media, representative exposure pathways from residual radioactivity, and a total of three receptors (under present and future use scenarios). Plausible receptors included a Resident Farmer, Recreational User, and Wildlife Worker. single radionuclide soil guidelines (outputs specified by the software modeling code) were generated for three receptors and thirteen targeted radionuclides. These soil guidelines were based on satisfying the project dose constraints. For comparison, soil guidelines applicable to the basic radiation public dose limit of 100 mrem/yr were generated. Single radionuclide soil guidelines from the most limiting (restrictive) receptor based on a target dose constraint of 25 mrem/yr were then rounded and identified as the derived soil guidelines. An additional evaluation using the derived soil

  19. Dose Modeling Evaluations and Technical Support Document For the Authorized Limits Request for the DOE-Owned Property Outside the Limited Area, Paducah Gaseous Diffusion Plant Paducah, Kentucky

    International Nuclear Information System (INIS)

    Boerner, A. J.

    2012-01-01

    Environmental assessments and remediation activities are being conducted by the U.S. Department of Energy (DOE) at the Paducah Gaseous Diffusion Plant (PGDP), Paducah, Kentucky. The Oak Ridge Institute for Science and Education (ORISE), a DOE prime contractor, was contracted by the DOE Portsmouth/Paducah Project Office (DOE-PPPO) to conduct radiation dose modeling analyses and derive single radionuclide soil guidelines (soil guidelines) in support of the derivation of Authorized Limits (ALs) for 'DOE-Owned Property Outside the Limited Area' ('Property') at the PGDP. The ORISE evaluation specifically included the area identified by DOE restricted area postings (public use access restrictions) and areas licensed by DOE to the West Kentucky Wildlife Management Area (WKWMA). The licensed areas are available without restriction to the general public for a variety of (primarily) recreational uses. Relevant receptors impacting current and reasonably anticipated future use activities were evaluated. In support of soil guideline derivation, a Conceptual Site Model (CSM) was developed. The CSM listed radiation and contamination sources, release mechanisms, transport media, representative exposure pathways from residual radioactivity, and a total of three receptors (under present and future use scenarios). Plausible receptors included a Resident Farmer, Recreational User, and Wildlife Worker. single radionuclide soil guidelines (outputs specified by the software modeling code) were generated for three receptors and thirteen targeted radionuclides. These soil guidelines were based on satisfying the project dose constraints. For comparison, soil guidelines applicable to the basic radiation public dose limit of 100 mrem/yr were generated. Single radionuclide soil guidelines from the most limiting (restrictive) receptor based on a target dose constraint of 25 mrem/yr were then rounded and identified as the derived soil guidelines. An additional evaluation using the derived soil

  20. ENZYME ACTIVITY PROBE AND GEOCHEMICAL ASSESSMENT FOR POTENTIAL AEROBIC COMETABOLISM OF TRICHLOROETHENE IN GROUNDWATER OF THE NORTHWEST PLUME, PADUCAH GASEOUS DIFFUSION PLANT, KENTUCKY

    International Nuclear Information System (INIS)

    Looney, B; M. Hope Lee, M; S. K. Hampson, S

    2008-01-01

    The overarching objective of the Paducah Gaseous Diffusion Plant (PGDP) enzyme activity probe (EAP) effort is to determine if aerobic cometabolism is contributing to the attenuation of trichloroethene (TCE) and other chlorinated solvents in the contaminated groundwater beneath PGDP. The site-specific objective for the EAP assessment is to identify if key metabolic pathways are present and expressed in the microbial community--namely the pathways that are responsible for degradation of methane and aromatic (e.g. toluene, benzene, phenol) substrates. The enzymes produced to degrade methane and aromatic compounds also break down TCE through a process known as cometabolism. EAPs directly measure if methane and/or aromatic enzyme production pathways are operating and, for the aromatic pathways, provide an estimate of the number of active organisms in the sampled groundwater. This study in the groundwater plumes at PGDP is a major part of a larger scientific effort being conducted by Interstate Technology and Regulatory Council (ITRC), U.S. Department of Energy (DOE) Office of Environmental Management (EM), Savannah River National Laboratory (SRNL), and North Wind Inc. in which EAPs are being applied to contaminated groundwater from diverse hydrogeologic and plume settings throughout the U.S. to help standardize their application as well as their interpretation. While EAP data provide key information to support the site specific objective for PGDP, several additional lines of evidence are being evaluated to increase confidence in the determination of the occurrence of biodegradation and the rate and sustainability of aerobic cometabolism. These complementary efforts include: (1) Examination of plume flowpaths and comparison of TCE behavior to 'conservative' tracers in the plume (e.g., 99 Tc); (2) Evaluation of geochemical conditions throughout the plume; and (3) Evaluation of stable isotopes in the contaminants and their daughter products throughout the plume. If the

  1. A Technical Assessment Of The Current Water Policy Boundary At U.S. Department Of Energy, Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    International Nuclear Information System (INIS)

    None

    2012-01-01

    In 1988, groundwater contaminated with trichloroethene (TCE) and technetium-99 (Tc-99) was identified in samples collected from residential water wells withdrawing groundwater from the Regional Gravel Aquifer (RGA) north of the Paducah Gaseous Diffusion Plant (PGDP) facility. In response, the U.S. Department of Energy (DOE) provided temporary drinking water supplies to approximately 100 potentially affected residents by initially supplying bottled water, water tanks, and water-treatment systems, and then by extending municipal water lines, all at no cost, to those persons whose wells could be affected by contaminated groundwater. The Water Policy boundary was established in 1993. In the Policy, DOE agreed to pay the reasonable monthly cost of water for homes and businesses and, in exchange, many of the land owners signed license agreements committing to cease using the groundwater via rural water wells. In 2012, DOE requested that Oak Ridge Associated Universities (ORAU), managing contractor of Oak Ridge Institute for Science and Education (ORISE), provide an independent assessment of the quality and quantity of the existing groundwater monitoring data and determine if there is sufficient information to support a modification to the boundary of the current Water Policy. As a result of the assessment, ORAU concludes that sufficient groundwater monitoring data exists to determine that a shrinkage and/or shift of the plume(s) responsible for the initial development of this policy has occurred. Specifically, there is compelling evidence that the TCE plume is undergoing shrinkage due to natural attenuation and associated degradation. The plume shrinkage (and migration) has also been augmented in local areas where large volumes of groundwater were recovered by pump-and treat remedial systems along the eastern and western boundaries of the Northwest Plume, and in other areas where pump-and-treat systems have been deployed by DOE to remove source contaminants. The

  2. Operational experience of gaseous effluent treatment at the Eurochemic reprocessing plant

    International Nuclear Information System (INIS)

    Osipenco, A.; Detilleux, E.

    1977-01-01

    The EUROCHEMIC fuel reprocessing plant applies the PUREX flow sheet. Two particular features of the plant influence gaseous and liquid effluents: chemical decanning and the ability to process a wide range of fuels, uranium metal or oxide, having an initial enrichment typical of power reactors (up to 5%) or material testing reactors (up to 93%). The ventilation circuits, treatment plant and monitoring equipment for gaseous releases are briefly described. No retention facilities for rare gases, tritium, or carbon-14 are provided. The releases are monitored for krypton-85, iodine-131, alpha and beta-gamma aerosols and tritium. Between 1966 and 1974 the plant processes about 200 tonnes of power reactor fuel, from which about 0.7 tonnes of plutonium and 1.5 tonnes of highly enriched uranium were separated. The most important points in the operation of the gas cleaning equipment are indicated: efficiency, operational reliability, incidents, etc.. Actual discharges as measured are compared with the limits set in the operation licence. Using the atmospheric diffusion coefficients, the dose commitment is estimated. The low level liquid effluents are passed, after neutralization, to the treatment plant of the Belgian nuclear center CEN/SCK. However, if the activity exceeds the limit set by the CEN/SCK, the effluents are concentrated by evaporation and stored on the EUROCHEMIC site. (orig.) [de

  3. Preliminary Results of Reductive Dechlorination Conducted at the X-749/X-120 Area of the DOE Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    International Nuclear Information System (INIS)

    Rieske, D. E.; Baird, D. R.; Lawson, N. E.

    2006-01-01

    Reductive dechlorination is being implemented at the X-749/X-120 trichloroethene (TCE) plume South Barrier Wall containment site at the Department of Energy (DOE) Portsmouth Gaseous Diffusion Plant (PORTS). The purpose of this paper is to present the effectiveness of the reductive dechlorination at PORTS. Reductive dechlorination is an in situ remediation technology that utilizes existing subsurface microbes to biologically degrade volatile organic compounds in groundwater. Monitoring in the barrier wall area reveals the presence of Hydrogen Release Compound (HRC) injected in the spring of 2004 in two groundwater monitoring wells closest to the injection points. Oxidation/reduction potential in these two wells has decreased steadily since injection, but has not yet reached optimal reducing levels for TCE degradation. Monitoring the effectiveness of the injection is hampered by near-stagnant groundwater flow due in part to the South Barrier Wall. The X-749/X-120 TCE groundwater plume lies beneath approximately 91 acres in the southern portion of PORTS, and extends southward threatening to cross the DOE property boundary. A 1,077-foot long subsurface bentonite barrier wall was installed in 1993 at the southern DOE property boundary to restrict movement of contaminated groundwater from traveling off-site until other remedial technologies could be implemented. In 2003, TCE was detected on the south side of the barrier wall (but still within DOE property) above drinking water standards of 5 micrograms per liter. Monitoring has also detected TCE in groundwater beyond the western edge of the barrier wall. In the spring of 2004, DOE initiated the injection of a reductive dechlorination compound known as Hydrogen Release Compound-extended release formula (HRC-X) into the subsurface using direct push technology (DPT). The HRC-X was injected within the saturated zone from the top of bedrock to 10 feet above bedrock as the probe was withdrawn from the push. A total of 180 DPT

  4. Historical review of CEA researches on uranium enrichment

    International Nuclear Information System (INIS)

    Camarcat, N.

    1997-01-01

    The various uranium enrichment processes that have been studied at the CEA since 1953 are briefly reviewed: gaseous diffusion (which led to the construction of EURODIF plant), chemical treatments (which were abandoned in 1988 for cost reasons), gaseous ultracentrifugation, electromagnetic processes, laser techniques (since 1980) and especially the SILVA technique (atomic vapour laser isotopic separation) which could take the place of the gaseous diffusion technique when the EURODIF plant will need to be renewed before 2010

  5. EURODIF: An enrichment plant for the present and beyond the year 2000

    International Nuclear Information System (INIS)

    Petit, J.F.; Barre, J.Y.

    1989-01-01

    EURODIF's George Besse uranium enrichment plant, which uses the gaseous diffusion process, was set up in France with European partners. It has the annual capacity to supply sufficient enriched uranium for 100 light water reactors of 900 MWe. The plant has been running for the last 10 years and its output is set to satisfy the market for enrichment, while making best use of the seasonal availability of electrical energy supplied by the EdF. In 80,000 hours of operation the plant has proved itself entirely satisfactory in terms of reliability, availability, safety and efficiency. From this, it can be predicted that, on the basis of current production, output can be maintained to beyond the year 2000. The improvement programme being undertaken at present will increase performance and flexibility and make the plant more competitive as it enters the market of the next decade

  6. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Oak Ridge Gaseous Diffusion Plant Site

    Energy Technology Data Exchange (ETDEWEB)

    1991-09-01

    In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) technology, with the near-term goal to provide the necessary information to make a deployment decision by November 1992. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. A programmatic document for use in screening DOE sites to locate the U-AVLIS production plant was developed and implemented in two parts (Wolsko et al. 1991). The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were then subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the ORGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use, socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3. Following the site description and additional data requirements, Sec. 4 provides a short, qualitative assessment of potential environmental issues. 37 refs., 20 figs., 18 tabs.

  7. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Oak Ridge Gaseous Diffusion Plant Site

    International Nuclear Information System (INIS)

    1991-09-01

    In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) technology, with the near-term goal to provide the necessary information to make a deployment decision by November 1992. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. A programmatic document for use in screening DOE sites to locate the U-AVLIS production plant was developed and implemented in two parts (Wolsko et al. 1991). The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were then subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the ORGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use, socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3. Following the site description and additional data requirements, Sec. 4 provides a short, qualitative assessment of potential environmental issues. 37 refs., 20 figs., 18 tabs

  8. Microscale diffusion analysis of gaseous radioactive effluents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Byung Woo; Chang, Kwang Phil; Jeong, Guy Soo; Lee, Kwang Hee; Choi, Yong Seok; An, Jin Young [Sungkyunkwan University, Seoul (Korea, Republic of)

    1997-07-01

    The state-of-the art review and relevant data bases have been made in this study. Microscale wind-field model has been made and applied to the site= of a target domestic plant - Younggwang units. Following researches have been made; - Review of modeling status in U.S.A., European countries, and Japan, those theoretical backgrounds, and experimental activities - Graphical display of topographical grid data in the surrounding with the Younggwang N.P.P. and basic investigation of the surrounding geography - Survey of site meteorological data of the Younggwang N.P.P.; precipitation distribution, yearly average wind direction and joint frequency, seasonal wind rose, distribution of seasonal sea and land breeze, joint frequency with respect to the atmospheric stability, mixing height - Presentation of a draft to update the existing Korea real-time dose assessment system, FADAS and to interface to the AWS(Automatic Weather System) of the Korea Meteorology Administration. - Establishment of nested-grid system with micro- and macro- scale cells around the Younggwang nuclear power plant -Consideration of solar radiation effect by using land-use map -Analysis of wind field in the region of 30 x 30 km n the Younggwang site (Author) 67 refs., 20 tabs., 28 figs.

  9. Crescimento e índices de troca gasosa em plantas de pepino irrigadas com água enriquecida com CO2 Growth analysis and gaseous exchange in cucumber plants irrigated with carbon dioxide enriched water

    Directory of Open Access Journals (Sweden)

    Kathia A.L. Canizares

    2004-12-01

    physiological indices and gaseous exchange of leaves of Japanese cucumber plants. The experimental design was of randomized blocks, with four and five replications. The treatments consisted of the hybrids Hokuho and Tsuyataro, irrigated with water enriched or not with CO2, 1‰ in the first semester and 0,25‰ in the second. Dry mass weight and leaf area presented an exponential tendency. The beginning of mass production decrease on dry matter, 63 days after transplanting date (DAT, was not possible to be observed. The growth rate and relative growth rate response of hybrid Hokuho differed between treatments, however, for hybrid Tsuyataro the response was similar. The net assimilation rate reached the pending maxim in the phase of vegetative growth and flowering, and was reduced drastically after 20 DAT for hybrid Hokuho, and after the 35 DAT for hybrid Tsuyataro. The leaf area rate from both hybrids decreases lightly during the cultivation, without differences between enriched and non enriched water after 20 DAT. The CO2 assimilation transpiration rate, stomatal conductance and water use efficiency were similar among plants irrigated with enriched and non enriched water during the first semester. Already in the second semester, higher values were observed in plants irrigated with enriched water.

  10. 10 CFR Appendix C to Part 110 - Illustrative List of Gaseous Diffusion Enrichment Plant Assemblies and Components Under NRC...

    Science.gov (United States)

    2010-01-01

    ... are made of, or lined with, materials resistant to UF6. 1.4 Rotary Shaft Seals Especially designed or prepared vacuum seals, with seal feed and seal exhaust connections, for sealing the shaft connecting the... cooling the gas (which is heated by the process of compression), seal valves and control valves, and...

  11. Method and apparatus for rapid adjustment of process gas inventory in gaseous diffusion cascades

    International Nuclear Information System (INIS)

    1980-01-01

    A method is specified for the operation of a gaseous diffusion cascade wherein electrically driven compressors circulate a process gas through a plurality of serially connected gaseous diffusion stages to establish first and second countercurrently flowing cascade streams of process gas, one of the streams being at a relatively low pressure and enriched in a component of the process gas and the other being at a higher pressure and depleted in the same, and wherein automatic control systems maintain the stage process gas pressures by positioning process gas flow control valve openings at values which are functions of the difference between reference-signal inputs to the systems, and signal inputs proportional to the process gas pressures in the gaseous diffusion stages associated with the systems, the cascade process gas inventory being altered, while the cascade is operating, by simultaneously directing into separate process-gas freezing zones a plurality of substreams derived from one of the first and second streams at different points along the lengths thereof to solidify approximately equal weights of process gas in the zone while reducing the reference-signal inputs to maintain the positions of the control valves substantially unchanged despite the removal of process gas inventory via the substreams. (author)

  12. Gaseous diffusion flames: simple structures and their interaction

    Energy Technology Data Exchange (ETDEWEB)

    Cavaliere, A. [Universita degli Studi Federico II, Naples (Italy). Dip. di Ingegneria Chimica; Ragucci, R. [Istituto di Ricerche sulla Combustione C,N.R., Naples (Italy)

    2001-07-01

    This is a synoptic overview of a selection of works dealing with single diffusive structures, with their mutual interaction in simple flows and their statistical modeling in complex flows. The focus is on reacting conditions pertaining to gaseous diffusion flames, but isothermal structures are also described when they are of some conceptual interest. This paper considers only few representative works for each subject, which are functional in explaining the key characteristics of the diffusive structures. The extension, given to single subjects, is not weighed according to the number of related publications but on the relevance to the basic understanding of the general framework concerning diffusion flames. One-dimensional structures are first discussed. They are ordered according to the number of balance equation terms needed for their description. Two-dimensional (2D) structures are then introduced following an order based on their convolution level. Some pioneering work on three-dimensional structures is further quoted. The temporal evolution of simple structures in quiescent or simple flowing 2D systems is considered. The latter case is exploited to present classification of diffusion-controlled mixing regimes. Modeling characterization approach of turbulent diffusion flames is also described in order to yield a self-sufficient didactic presentation. The approach based on the flame surface density model is specifically discussed because of its potential use in the determination of qualitative and quantitative features of simple diffusion flames. (author)

  13. Fundamental laws of separation by the gaseous diffusion process

    International Nuclear Information System (INIS)

    Bouligand, G.M.

    1964-01-01

    Using the Knudsen's law for the flow of each component of a gaseous mixture through a porous membrane, we derive the overall separation laws and the separation power for one stage of diffusion: Various types of stages differing by the geometrical configuration and the flow nature are considered. For the sake of simplicity physical phenomena causing a loss of separation efficiency are neglected. Computation show the advantages of counter-current type stage with one entering and two leaving flows. A more refined theory of separation can be derived with the same basis of this work. (author) [fr

  14. Near real-time inventory and accountability within a uranium enrichment plant

    International Nuclear Information System (INIS)

    Wheeler, L.E.; Scott, P.H.

    1983-01-01

    The Oak Ridge Gaseous Diffusion Plant Inventory Control and Accountability System (ORICAS) utilizes state-of-the-art hardware, software, and communication to provide a computerized near real-time inventory of materials within a Uranium Enrichment Plant. Work stations are located in five strategic areas within the plant. Accountability areas include material receipt, enrichment, withdrawal, sampling, intraplant transfer, and shipment. Perpetual current inventory is maintained and is available to authorized users on-line and in printed reports. The system meets DOE material reporting requirements and provides accountability safeguards for early detection of possible loss or diversion. Hardware consists of multiple data input terminals and printers linked to a time-shared computer. Major software includes COBOL and IDMS (an Integrated Data Base Management System)

  15. Unattended safeguards instrumentation at centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Smith, L. Eric; Lebrun, Alain R.; Labella, Rocco

    2014-01-01

    As global uranium enrichment capacity under international safeguards expands, the International Atomic Energy Agency (IAEA) is challenged to develop effective safeguards approaches at gaseous centrifuge enrichment plants, particularly high‑capacity plants, while working within budgetary constraints. New safeguards approaches should meet the high‑level verification objectives for such facilities (i.e., timely detection of: diversion of declared material, excess production beyond declared amounts, and production of enrichment levels higher than declared), but should also strive for efficiency advantages in implementation, for both the IAEA and operators. Under the Agency’s State- level approach to safeguards implementation, the Agency needs a flexible toolbox of technologies, allowing tailoring of safeguards measures for each individual enrichment facility. In this paper, the potential roles and development status for three different types of unattended measurement instrumentation are discussed. On‑Line Enrichment Monitors (OLEM) could provide continuous enrichment measurement for 100% of the declared gas flowing through unit header pipes. Unattended Cylinder Verification Stations (UCVS) could provide unattended verification of the declared uranium mass and enrichment of 100% of the cylinders moving through the plant, but also apply and verify an ‘NDA Fingerprint’ to preserve verification knowledge on the contents of each cylinder throughout its life in the facility. Sharing of the operator’s load cell signals from feed and withdrawal stations could count all cylinders introduced to the process and provide periodic monitoring of the uranium mass balance for in‑process material. The integration of load cell, OLEM and UCVS data streams offers the possibility for 100% verification of declared cylinder flow, and enables the periodic verification of the declared 235 U mass balance in the plant. These new capabilities would enhance the IAEA

  16. Analysis of radiation fields in tomography on diffusion gaseous sound

    International Nuclear Information System (INIS)

    Bekman, I.N.

    1999-01-01

    Perspectives of application of equilibrium and stationary variants of diffusion tomography with radioactive gaseous sounds for spatial reconstruction of heterogeneous media in materials technology were considered. The basic attention were allocated to creation of simple algorithms of detection of sound accumulation on the background of monotonically varying concentration field. Algorithms of transformation of two-dimensional radiation field in three-dimensional distribution of radiation sources were suggested. The methods of analytical elongation of concentration field permitting separation of regional anomalies on the background of local ones and vice verse were discussed. It was shown that both equilibrium and stationary variants of diffusion tomography detect the heterogeneity of testing material, provide reduction of spatial distribution of elements of its structure and give an estimation of relative degree of defectiveness

  17. Radioactive diffusion gaseous probe technique for study adsorbent structure inhomogeneity

    International Nuclear Information System (INIS)

    Zyuzin, A.Yu.; Korobkov, V.I.; Bekman, I.N.

    1990-01-01

    One of the versions of the method of diffusion gaseous probe - method of longitudinal shear in combination with autoradiography (ARG) - was used for characterising sorbents and catalysts, which are considered to be promising for reprocessing of sulfur-containing natural gases. Hydrogen sulfide, labelled with 35 S was used as diffusion radioactive probe. Zeolite granules of 4A type and granulated adsorbents on the basis of CR and AM aluminium oxides, which are industrial catalysts of Clauss reaction developed at SNEA company, were used as objects under investigation. It is shown that technique for fabrication of 4A zeolite granules leads to asymmetrical pore distribution over the granule diameter. Technique for AM granule fabrication leads to occuRrence of local inhomogeneities of the structure in the form of narrow coaxial rings with decreased or increased local adsorption ability. Granules of adsorbent of CR type are characterized by rather homogeneous structure. It is recommended to use the mentioned method for industrial adsorbent diagnosis

  18. Enrichment planting without soil treatment

    Energy Technology Data Exchange (ETDEWEB)

    Hagner, Mats

    1998-12-31

    Where enrichment planting had been carried out with either of the two species Picea abies and Pinus contorta, the survival of the planted seedlings was at least as good as after planting in a normal clear cut area treated with soil scarification. This was in spite of the fact that the seedlings were placed shallow in the humus layer without any soil treatment. However, they were sheltered from insects by treatment before planting. Where enrichment planting was carried out with Pinus sylvestris the survival in dense forest was poor, but in open forest the survival was good. The growth of planted seedlings was enhanced by traditional clearing and soil treatment. However, this was for Pinus sylvestris not enough to compensate for the loss of time, 1-2 years, caused by arrangement of soil scarification. The growth of seedlings planted under crown cover was directly related to basal area of retained trees. However, the variation in height growth among individual seedlings was very big, which meant that some seedlings grow well also under a fairly dense forest cover. The pioneer species Pinus sylvestris reacted more strongly to basal area of retained trees than did the shade tolerant species Picea abies. Enrichment planting seems to be a necessary tool for preserving volume productivity, at places where fairly intensive harvest of mature trees has been carried out in stands of ordinary forest type in central Sweden. If double seedlings, with one Picea abies and one Pinus sylvestris, are used, the probability for long term establishment is enhanced 13 refs, 20 figs, 4 tabs

  19. Fluorine nuclear magnetic resonance study of enrichment effects in gaseous, liquid and solid uranium hexafluoride

    International Nuclear Information System (INIS)

    Ursu, I.; Demco, D.E.; Simplaceanu, V.; Valcu, N.

    1977-01-01

    The nuclear magnetic resonance method is able to provide information concerning the isotopic content of 235 U in UF 6 by means of measuring the nuclear magnetic transverse relaxation time (T,L2) of 19 F nuclei in liquid UF 6 . In this work, the sources of errors in the T 2 measurements have been analysed and methods for reducing them are dicussed. Typical errors in T 2 determinations are below 2%. The enrichment estimations made by using the linear calibration curves had a deviation of less than 2% with some exceptions. It was found that the chemical impurities may significantly affect the enrichment estimations. 19 F NMR spectra of liquid and gaseous UF 6 at low pressures did not reveal any structure or enrichment effect. The longitudinal nuclear magnetic relaxation of 19 F nuclei in low pressure, gaseous and solid UF 6 showed no enrichment dependence, nor the dipolar relaxation time in solid UF 6 did. (author)

  20. Main results obtained in France in the development of the gaseous diffusion process for uranium isotope separation

    International Nuclear Information System (INIS)

    Frejacques, C.; Bilous, O.; Dixmier, J.; Massignon, D.; Plurien, P.

    1958-01-01

    The main problems which occur in the study of uranium isotope separation by the gaseous diffusion process, concern the development of the porous barrier, the corrosive nature of uranium hexafluoride and also the chemical engineering problems related to process design and the choice of best plant and stage characteristics. Porous barriers may be obtained by chemical attack of non porous media or by agglomeration of very fine powders. Examples of these two types of barriers are given. A whole set of measurement techniques were developed for barrier structure studies, to provide control and guidance of barrier production methods. Uranium hexafluoride reactivity and corrosive properties are the source of many difficult technological problems. A high degree of plant leak tightness must be achieved. This necessity creates a special problem in compressor bearing design. Barrier lifetime is affected by the corrosive properties of the gas, which may lead to a change of barrier structure with time. Barrier hexafluoride permeability measurements have helped to make a systematic study of this point. Finally an example of a plant flowsheet, showing stage types and arrangements and based on a minimisation of enriched product costs is also given as an illustration of some of the chemical engineering problems present. (author) [fr

  1. Control of uranium hazards - Portsmouth uranium enrichment plant

    International Nuclear Information System (INIS)

    Wagner, E.R.

    1985-01-01

    This report summarizes the Environmental, Safety and Health programs to control uranium hazards at the Portsmouth Gaseous Diffusion Plant. A description of the physical plant, the facility processes and the attendant uranium flows and effluents are provided. The hazards of uranium are discussed and the control systems are outlined. Finally, the monitoring programs are described and summaries of recent data are provided. 11 figs., 20 tabs

  2. Evaluation of natural attenuation processes for trichloroethylene and technetium-99 in the Northeast and Northwest plumes at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    International Nuclear Information System (INIS)

    Clausen, J.L.; Sturchio, N.C.; Heraty, L.J.; Huang, L.; Abrajano, T.

    1997-01-01

    NA processes such as biodegradation, sorption, dilution dispersion, advection, and possibly sorption and diffusion are occurring in the Northeast and Northwest plumes. However, the overall biological attenuation rate for TCE within the plumes is not sufficiently rapid to utilize as remedial option. The mobility and toxicity of 99 Tc is not being reduced by attenuating processes within the Northwest Plume. The current EPA position is that NA is not a viable remedial approach unless destructive processes are present or processes are active which reduce the toxicity and mobility of a contaminant. Therefore, active remediation of the dissolved phase plumes will be necessary to reduce contaminant concentrations before an NA approach could be justified at PGDP for either plume. Possible treatment methods for the reduction of dissolved phase concentrations within the plumes are pump-and-treat bioaugmentation, biostimulation, or multiple reactive barriers. Another possibility is the use of a regulatory instrument such as an Alternate Concentration Limit (ACL) petition. Biodegradation of TCE is occurring in both plumes and several hypothesis are possible to explain the apparent conflicts with some of the geochemical data. The first hypothesis is active intrinsic bioremediation is negligible or so slow to be nonmeasurable. In this scenario, the D.O., chloride, TCE, and isotopic results are indicative of past microbiological reactions. It is surmised in this scenario, that when the initial TCE release occurred, sufficient energy sources were available for microorganisms to drive aerobic reduction of TCE, but these energy sources were rapidly depleted. The initial degraded TCE has since migrated to downgradient locations. In the second scenario, TCE anaerobic degradation occurs in organic-rich micro-environments within a generally aerobic aquifer. TCE maybe strongly absorbed to organic-rich materials in the aquifer matrix and degraded by local Immunities of microbes, perhaps

  3. Evaluation of natural attenuation processes for trichloroethylene and technetium-99 in the Northeast and Northwest plumes at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    Clausen, J.L.; Sturchio, N.C.; Heraty, L.J.; Huang, L.; Abrajano,T.

    1997-11-25

    NA processes such as biodegradation, sorption, dilution dispersion, advection, and possibly sorption and diffusion are occurring in the Northeast and Northwest plumes. However, the overall biological attenuation rate for TCE within the plumes is not sufficiently rapid to utilize as remedial option. The mobility and toxicity of {sup 99}Tc is not being reduced by attenuating processes within the Northwest Plume. The current EPA position is that NA is not a viable remedial approach unless destructive processes are present or processes are active which reduce the toxicity and mobility of a contaminant. Therefore, active remediation of the dissolved phase plumes will be necessary to reduce contaminant concentrations before an NA approach could be justified at PGDP for either plume. Possible treatment methods for the reduction of dissolved phase concentrations within the plumes are pump-and-treat bioaugmentation, biostimulation, or multiple reactive barriers. Another possibility is the use of a regulatory instrument such as an Alternate Concentration Limit (ACL) petition. Biodegradation of TCE is occurring in both plumes and several hypothesis are possible to explain the apparent conflicts with some of the geochemical data. The first hypothesis is active intrinsic bioremediation is negligible or so slow to be nonmeasurable. In this scenario, the D.O., chloride, TCE, and isotopic results are indicative of past microbiological reactions. It is surmised in this scenario, that when the initial TCE release occurred, sufficient energy sources were available for microorganisms to drive aerobic reduction of TCE, but these energy sources were rapidly depleted. The initial degraded TCE has since migrated to downgradient locations. In the second scenario, TCE anaerobic degradation occurs in organic-rich micro-environments within a generally aerobic aquifer. TCE maybe strongly absorbed to organic-rich materials in the aquifer matrix and degraded by local Immunities of microbes

  4. Enrichment plants. A survey of major new uranium enriching projects

    International Nuclear Information System (INIS)

    Kovan, D.

    1976-01-01

    The work enrichment situation is reported. The development of enrichment in the U.S. and in Europe is outlined. A brief description is given of the technology of separation by diffusion and by centrifugation and the advantages and disadvantages of the two processes are compared. Finally the supply and demand situation is briefly considered. (U.K.)

  5. United States uranium enrichment policies

    International Nuclear Information System (INIS)

    Roberts, R.W.

    1977-01-01

    ERDA's uranium enrichment program policies governing the manner in which ERDA's enrichment complex is being operated and expanded to meet customer requirements for separative work, research and development activities directed at providing technology alternatives for future enrichment capacity, and establishing the framework for additional domestic uranium enrichment capacity to meet the domestic and foreign nuclear industry's growing demand for enrichment services are considered. The ERDA enrichment complex consists of three gaseous diffusion plants located in Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio. Today, these plants provide uranium enrichment services for commercial nuclear power generation. These enrichment services are provided under contracts between the Government and the utility customers. ERDA's program involves a major pilot plant cascade, and pursues an advanced isotope separation technique for the late 1980's. That the United States must develop additional domestic uranium enrichment capacity is discussed

  6. A study on the diffusion of gaseous radioactive effluents based on the statistical method

    International Nuclear Information System (INIS)

    Na, Man Gyun; Lee, Goung Jin

    1998-01-01

    A diffusion model of radioactive gaseous effluents is improved to apply for domestic nuclear power plants. Up to now, XOQDOQ computer code package developed by U. S NRC has been used for the assessment of radioactive plume dispersion by normal operation of domestic nuclear power plants. XOQDOQ adopts the straight-line Gaussian plume model which was basically derived for the plane terrain. However, since there are so many mountains in Korea, the several shortcomings of XOQDOQ are improved to consider the complex terrain effects. In this work, wind direction change is considered by modifying the wind rose frequency using meteorological data of the local weather stations. In addition, an effective height correction model, a plume reduction model due to plume penetration into mountain, and a wet deposition model are adopted for more realistic assessments. The proposed methodology is implemented in Yonggwang nuclear power plants, and can be used for other domestic nuclear power plants

  7. Independent Technical Review Of The Focused Feasibility Study And Proposed Plan For Designated Solid Waste Management Units Contributing To The Southwest Groundwater Plume At The Paducah Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Looney, B.; Eddy-Dilek, C.; Amidon, M.; Rossabi, J.; Stewart, L.

    2011-01-01

    The U. S. Department of Energy (DOE) is currently developing a Proposed Plan (PP) for remediation of designated sources of chlorinated solvents that contribute contamination to the Southwest (SW) Groundwater Plume at the Paducah Gaseous Diffusion Plant (PGDP), in Paducah, KY. The principal contaminants in the SW Plume are trichloroethene (TCE) and other volatile organic compounds (VOCs); these industrial solvents were used and disposed in various facilities and locations at PGDP. In the SW plume area, residual TCE sources are primarily in the fine-grained sediments of the Upper Continental Recharge System (UCRS), a partially saturated zone that delivers contaminants downward into the coarse-grained Regional Gravel Aquifer (RGA). The RGA serves as the significant lateral groundwater transport pathway for the plume. In the SW Plume area, the four main contributing TCE source units are: (1) Solid Waste Management Unit (SWMU) 1 / Oil Landfarm; (2) C-720 Building TCE Northeast Spill Site (SWMU 211A); (3) C-720 Building TCE Southeast Spill Site (SWMU 211B); and (4) C-747 Contaminated Burial Yard (SWMU 4). The PP presents the Preferred Alternatives for remediation of VOCs in the UCRS at the Oil Landfarm and the C-720 Building spill sites. The basis for the PP is documented in a Focused Feasibility Study (FFS) (DOE, 2011) and a Site Investigation Report (SI) (DOE, 2007). The SW plume is currently within the boundaries of PGDP (i.e., does not extend off-site). Nonetheless, reasonable mitigation of the multiple contaminant sources contributing to the SW plume is one of the necessary components identified in the PGDP End State Vision (DOE, 2005). Because of the importance of the proposed actions DOE assembled an Independent Technical Review (ITR) team to provide input and assistance in finalizing the PP.

  8. INDEPENDENT TECHNICAL REVIEW OF THE FOCUSED FEASIBILITY STUDY AND PROPOSED PLAN FOR DESIGNATED SOLID WASTE MANAGEMENT UNITS CONTRIBUTING TO THE SOUTHWEST GROUNDWATER PLUME AT THE PADUCAH GASEOUS DIFFUSION PLANT

    Energy Technology Data Exchange (ETDEWEB)

    Looney, B.; Eddy-Dilek, C.; Amidon, M.; Rossabi, J.; Stewart, L.

    2011-05-31

    The U. S. Department of Energy (DOE) is currently developing a Proposed Plan (PP) for remediation of designated sources of chlorinated solvents that contribute contamination to the Southwest (SW) Groundwater Plume at the Paducah Gaseous Diffusion Plant (PGDP), in Paducah, KY. The principal contaminants in the SW Plume are trichloroethene (TCE) and other volatile organic compounds (VOCs); these industrial solvents were used and disposed in various facilities and locations at PGDP. In the SW plume area, residual TCE sources are primarily in the fine-grained sediments of the Upper Continental Recharge System (UCRS), a partially saturated zone that delivers contaminants downward into the coarse-grained Regional Gravel Aquifer (RGA). The RGA serves as the significant lateral groundwater transport pathway for the plume. In the SW Plume area, the four main contributing TCE source units are: (1) Solid Waste Management Unit (SWMU) 1 / Oil Landfarm; (2) C-720 Building TCE Northeast Spill Site (SWMU 211A); (3) C-720 Building TCE Southeast Spill Site (SWMU 211B); and (4) C-747 Contaminated Burial Yard (SWMU 4). The PP presents the Preferred Alternatives for remediation of VOCs in the UCRS at the Oil Landfarm and the C-720 Building spill sites. The basis for the PP is documented in a Focused Feasibility Study (FFS) (DOE, 2011) and a Site Investigation Report (SI) (DOE, 2007). The SW plume is currently within the boundaries of PGDP (i.e., does not extend off-site). Nonetheless, reasonable mitigation of the multiple contaminant sources contributing to the SW plume is one of the necessary components identified in the PGDP End State Vision (DOE, 2005). Because of the importance of the proposed actions DOE assembled an Independent Technical Review (ITR) team to provide input and assistance in finalizing the PP.

  9. Measurement of the enrichment of uranium in the pipework of a gas centrifuge enrichment plant

    International Nuclear Information System (INIS)

    Packer, T.W.; Lees, E.W.; Close, D.; Nixon, K.V.; Pratt, J.C.; Strittmatter, R.

    1985-01-01

    The US and UK have been separately working on the development of a NDA instrument to determine the enrichment of gaseous UF 6 at low pressures in cascade header pipework in line with the conclusions of the Hexapartite Safeguards Project viz. the instrument is capable of making a ''go/no go'' decision of whether the enrichment is less than/greater than 20%. Recently, there has been a series of very useful technical exchanges of ideas and information between the two countries. This has led to a technical formulation for such an instrumentation based on γ-ray spectrometry which, although plant-specific in certain features, nevertheless is based on the same physical principles. Experimental results from commercially operating enrichment plants are very encouraging and indicate that a complete measurement including set up time on the pipe should be attainable in about 30 minutes when measuring pipes of diameter around 110 mm. 5 refs., 4 figs

  10. Treatment of Plants with Gaseous Ethylene and Gaseous Inhibitors of Ethylene Action.

    Science.gov (United States)

    Tucker, Mark L; Kim, Joonyup; Wen, Chi-Kuang

    2017-01-01

    The gaseous nature of ethylene affects not only its role in plant biology but also how you treat plants with the hormone. In many ways, it simplifies the treatment problem. Other hormones have to be made up in solution and applied to some part of the plant hoping the hormone will be taken up into the plant and translocated throughout the plant at the desired concentration. Because all plant cells are connected by an intercellular gas space the ethylene concentration you treat with is relatively quickly reached throughout the plant. In some instances, like mature fruit, treatment with ethylene initiates autocatalytic synthesis of ethylene. However, in most experiments, the exogenous ethylene concentration is saturating, usually >1 μL L -1 , and the synthesis of additional ethylene is inconsequential. Also facilitating ethylene research compared with other hormones is that there are inhibitors of ethylene action 1-MCP (1-methylcyclopropene) and 2,5-NBD (2,5-norbornadiene) that are also gases wherein you can achieve nearly 100% inhibition of ethylene action quickly and with few side effects. Inhibitors for other plant hormones are applied as a solution and their transport and concentration at the desired site is not always known and difficult to measure. Here, our focus is on how to treat plants and plant parts with the ethylene gas and the gaseous inhibitors of ethylene action.

  11. Equilibrium sorptive enrichment on poly(dimethylsiloxane) particles for trace analysis of volatile compounds in gaseous samples

    NARCIS (Netherlands)

    Baltussen, H.A.; David, F.; Sandra, P.J.F.; Janssen, J.G.M.; Cramers, C.A.M.G.

    1999-01-01

    A novel approach for sample enrichment, namely, equilibrium sorptive enrichment (ESE), is presented. A packed bed of sorption (or partitioning) material is used to enrich volatiles from gaseous samples. Normally, air sampling is stopped before breakthrough occurs, but this approach is not very

  12. Gasket for uranium enrichment plant

    Energy Technology Data Exchange (ETDEWEB)

    Kishi, S; Aiyoshi, H

    1977-02-08

    A gasket to be inserted between flange joints in the equipments and pipe lines of an uranium enrichment plant having neither permeability nor adsorptivity to water while maintaining mechanical, physical and chemical properties of an elastomer gasket is described. A gasket made of an elastomeric material such as a polymer is integratedly formed at its surface with anti-slip projections. The gasket is further surrounded at its upper and lower peripheral sides, as well as outer circumferential portion with a U-sectioned cover (enclosure) made of fluoro-plastics. In this arrangement, the gasket main body shows a gas-tightness for uranium hexafluoride gas and the cover exhibits a gas-tightness for other component gases such as moisture to thereby prevent degradation of the gasket due to absorption and permeation of the moisture.

  13. Airborne effluent control at fuel enrichment, conversion, and fabrication plants

    International Nuclear Information System (INIS)

    Mitchell, M.E.

    1976-01-01

    Uranium conversion, enrichment, and fuel fabrication facilities generate gaseous wastes that must be treated prior to being discharged to the atmosphere. Since all three process and/or handle similar compounds, they also encounter similar gaseous waste disposal problems, the majority of which are treated in a similar manner. Ventilation exhausts from personnel areas and equipment off-gases that do not contain corrosive gases (such as HF) are usually passed through roughening and/or HEPA filters prior to release. Ventilation exhausts that contain larger quantities of particles, such as the conversion facilities' U 3 O 8 sampling operation, are passed through bag filters or cyclone separators, while process off-gases containing corrosive materials are normally treated by sintered metal filters or scrubbers. The effectiveness of particle removal varies from about 90 percent for a scrubber alone to more than 99.9 percent for HEPA filters or a combination of the various filters and scrubbers. The removal of nitrogen compounds (N 2 , HNO 3 , NO/sub x/, and NH 3 ) is accomplished by scrubbers in the enrichment and fuel fabrication facilities. The conversion facility utilizes a nitric acid recovery facility for both pollution control and economic recovery of raw materials. Hydrogen removal from gaseous waste streams is generally achieved with burners. Three different systems are currently utilized by the conversion, enrichment, and fuel fabrication plants to remove gaseous fluorides from airborne effluents. The HF-rich streams, such as those emanating from the hydrofluorination and fluorine production operations of the conversion plant, are passed through condensers to recover aqueous hydrofluoric acid

  14. Conceptual design for the field test and evaluation of the gas-phase UF6 enrichment meter

    International Nuclear Information System (INIS)

    Strittmatter, R.B.; Leavitt, J.N.; Slice, R.W.

    1980-12-01

    An in-line enrichment monitor is being developed to provide real-time enrichment data for the gas-phase UF 6 feed stream of an enrichment plant. Data from proof-of-principle measurements using a laboratory prototype system are presented. A conceptual design for an enrichment monitor to be field tested and evaluated at the Oak Ridge Gaseous Diffusion Plant is reported

  15. New generation enrichment monitoring technology for gas centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Ianakiev, Kiril D.; Alexandrov, Boian S.; Boyer, Brian D.; Hill, Thomas R.; Macarthur, Duncan W.; Marks, Thomas; Moss, Calvin E.; Sheppard, Gregory A.; Swinhoe, Martyn T.

    2008-01-01

    The continuous enrichment monitor, developed and fielded in the 1990s by the International Atomic Energy Agency, provided a go-no-go capability to distinguish between UF 6 containing low enriched (approximately 4% 235 U) and highly enriched (above 20% 235 U) uranium. This instrument used the 22-keV line from a 109 Cd source as a transmission source to achieve a high sensitivity to the UF 6 gas absorption. The 1.27-yr half-life required that the source be periodically replaced and the instrument recalibrated. The instrument's functionality and accuracy were limited by the fact that measured gas density and gas pressure were treated as confidential facility information. The modern safeguarding of a gas centrifuge enrichment plant producing low-enriched UF 6 product aims toward a more quantitative flow and enrichment monitoring concept that sets new standards for accuracy stability, and confidence. An instrument must be accurate enough to detect the diversion of a significant quantity of material, have virtually zero false alarms, and protect the operator's proprietary process information. We discuss a new concept for advanced gas enrichment assay measurement technology. This design concept eliminates the need for the periodic replacement of a radioactive source as well as the need for maintenance by experts. Some initial experimental results will be presented.

  16. Safety of uranium enrichment plant

    International Nuclear Information System (INIS)

    Yonekawa, Shigeru; Morikami, Yoshio; Morita, Minoru; Takahashi, Tsukasa; Tokuyasu, Takashi.

    1991-01-01

    With respect to safety evaluation of the gas centrifuge enrichment facility, several characteristic problems are described as follows. Criticality safety in the cascade equipments can be obtained to maintain the enrichment of UF 6 below 5 %. External radiation dose equivalent rate of the 30B cylinder is low enough, the shield is not necessary. Penetration ratio of the two-stage HEPA filters for UF 6 aerosol is estimated at 10 -9 . From the experimental investigation, vacuum tightness is not damaged by destruction of gas centrifuge rotor. Carbon steel can be used for uranium enrichment equipments under the condition below 100degC. (author)

  17. On the theory of gaseous transport to plant canopies

    Science.gov (United States)

    Bache, D. H.

    Solutions of the convection-diffusion equations are developed to show the relationship between bulk transport parameters affecting gaseous transfer to plant canopies and local rates of transfer within the canopy. Foliage density is considered to be uniform and the drag coefficient of elements is specified by cd = γu- n with u as the local wind-speed and γ and n constants. Under conditions of high surface resistance, the bulk deposition velocity at the top of the canopy vg( h) approaches a limit defined by v g(h) = v̂gL p(1-ψ v̂gL p/u ∗) , where v̂g is the local deposition rate, Lp the effective foliage area, u ∗ the friction velocity and ψ a structure coefficient. From this, a criterion is proposed for defining the conditions in which the local resistances may be added in parallel. Comparisons with the external model for the bulk transport resistance rp = ra + rb + rc (where r p = 1/v g(h) and ra is a diffusive resistance between the apparent momentum sink and height h) shows that the bulk surface resistance r c = r̂s/L p( r̂s being a local surface resistance due to internal properties of the surface) and r b = overliner̂p-r a, appearing as an excess aerodynamic component; overliner̂p refers to the depth-averaged value of r̂p—the resistance to transfer through the laminar sublayer enveloping individual canopy elements. In conditions of zero surface resistance the bulk transport rate rp, o can be specified by r p,o/r a = E( r̂p/r̂∗) hq with E and q as constants, the term r̂p/r̂∗ referring to the resistances to mass and momentum transfer to canopy elements. A general expression is formulated for the sublayer Stanton number B -1  r bu ∗ at the extremes of high and zero surface resistance. In conditions of low surface resistance, it is shown that the terms rb + rc cannot be conveniently separated into equivalent aerodynamic and surface components as at the limit of high surface resistance. This conclusion is a departure from previous

  18. Fundamental laws of separation by the gaseous diffusion process; Lois de separation elementaires en diffusion gazeuse

    Energy Technology Data Exchange (ETDEWEB)

    Bouligand, G M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    Using the Knudsen's law for the flow of each component of a gaseous mixture through a porous membrane, we derive the overall separation laws and the separation power for one stage of diffusion: Various types of stages differing by the geometrical configuration and the flow nature are considered. For the sake of simplicity physical phenomena causing a loss of separation efficiency are neglected. Computation show the advantages of counter-current type stage with one entering and two leaving flows. A more refined theory of separation can be derived with the same basis of this work. (author) [French] A partir de la loi de Knudsen exprimant les debits elementaires des constituants d'un melange gazeux a travers une membrane poreuse on determine les lois et la puissance de separation de differents modeles de diffuseurs definie par leurs configurations et la nature des ecoulements gazeux. Four simplifier il n'a pas ete tenu compte des divers phenomenes physiques inherents a la diffusion et qui reduisent generalement le facteur de separation. Ces calculs font prevoir les avantages des diffuseurs du type contrecourant a trois ouvertures et peuvent servir de guide dans une theorie plus complete de la separation. (auteur)

  19. Fundamental laws of separation by the gaseous diffusion process; Lois de separation elementaires en diffusion gazeuse

    Energy Technology Data Exchange (ETDEWEB)

    Bouligand, G.M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    Using the Knudsen's law for the flow of each component of a gaseous mixture through a porous membrane, we derive the overall separation laws and the separation power for one stage of diffusion: Various types of stages differing by the geometrical configuration and the flow nature are considered. For the sake of simplicity physical phenomena causing a loss of separation efficiency are neglected. Computation show the advantages of counter-current type stage with one entering and two leaving flows. A more refined theory of separation can be derived with the same basis of this work. (author) [French] A partir de la loi de Knudsen exprimant les debits elementaires des constituants d'un melange gazeux a travers une membrane poreuse on determine les lois et la puissance de separation de differents modeles de diffuseurs definie par leurs configurations et la nature des ecoulements gazeux. Four simplifier il n'a pas ete tenu compte des divers phenomenes physiques inherents a la diffusion et qui reduisent generalement le facteur de separation. Ces calculs font prevoir les avantages des diffuseurs du type contrecourant a trois ouvertures et peuvent servir de guide dans une theorie plus complete de la separation. (auteur)

  20. Safety criteria of uranium enrichment plants

    International Nuclear Information System (INIS)

    Nardocci, A.C.; Oliveira Neto, J.M. de

    1994-01-01

    The applicability of nuclear reactor safety criteria applied to uranium enrichment plants is discussed, and a new criterion based on the soluble uranium compounds and hexafluoride chemical toxicities is presented. (L.C.J.A.). 21 refs, 4 tabs

  1. Process control of a gaseous diffusion cascade for isotopic separation of uranium

    International Nuclear Information System (INIS)

    Bilous, Olegh; Doneddu, F.

    1986-01-01

    Various aspects of dynamics and process control of a gaseous diffusion cascade are described. The cascade enriches uranium hexafluoride gas (HEX) in the light isotope of uranium in a countercurrent flow. The linearized equations describing the equipment models are derived. One can then write the mass balances on the high and low pressure sides of a stage and the overall heat balance of a stage. These heat and mass balances are linear difference equations on the stage number with time derivatives which are then replaced by jω factors to examine the effects of cyclic perturbations. The mass balances are first treated for a cascade section of 12 stages with temperatures assumed constant. The effect of a perturbation of pressure on one of the stages is described first for ω=0 (that is for steady state). Then Nyquist diagrams are obtained. The effect of transport change is also studied. Then temperature is introduced, assuming pressures to be constant. The cases of a section of 12 stages and a cascade of 120 stages are examined. Again Nyquist diagrams of temperature frequency response to a perturbation on one stage are calculated. Process control of the heat exchangers is introduced. The method used to solve the difference equations may be applied to other types of perturbations and to the complete scheme of process control. (author)

  2. Enrichment plant management and safeguards

    International Nuclear Information System (INIS)

    Hurt, N.H.

    1978-01-01

    The next increment of enrichment at Portsmouth will be gas centrifuge. The safeguards program at Portsmouth is discussed, including the DYMCAS system, the computerization, and the detectors. Control of the material access areas is discussed. The licensee material surveillance and verification program is also described

  3. Some theoretical aspects of capacity increment in gaseous diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Coates, J. H.; Guais, J. C.; Lamorlette, G.

    1975-09-01

    Facing to the sharply growing needs of enrichment services, the problem of implementing new capacities must be included in an optimized scheme spread out in time. In this paper the alternative solutions will be studied first for an unique increment decision, and then in an optimum schedule. The limits of the analysis will be discussed.

  4. LISSAT Analysis of a Generic Centrifuge Enrichment Plant

    International Nuclear Information System (INIS)

    Lambert, H; Elayat, H A; O'Connell, W J; Szytel, L; Dreicer, M

    2007-01-01

    The U.S. Department of Energy (DOE) is interested in developing tools and methods for use in designing and evaluating safeguards systems for current and future plants in the nuclear power fuel cycle. The DOE is engaging several DOE National Laboratories in efforts applied to safeguards for chemical conversion plants and gaseous centrifuge enrichment plants. As part of the development, Lawrence Livermore National Laboratory has developed an integrated safeguards system analysis tool (LISSAT). This tool provides modeling and analysis of facility and safeguards operations, generation of diversion paths, and evaluation of safeguards system effectiveness. The constituent elements of diversion scenarios, including material extraction and concealment measures, are structured using directed graphs (digraphs) and fault trees. Statistical analysis evaluates the effectiveness of measurement verification plans and randomly timed inspections. Time domain simulations analyze significant scenarios, especially those involving alternate time ordering of events or issues of timeliness. Such simulations can provide additional information to the fault tree analysis and can help identify the range of normal operations and, by extension, identify additional plant operational signatures of diversions. LISSAT analyses can be used to compare the diversion-detection probabilities for individual safeguards technologies and to inform overall strategy implementations for present and future plants. Additionally, LISSAT can be the basis for a rigorous cost-effectiveness analysis of safeguards and design options. This paper will describe the results of a LISSAT analysis of a generic centrifuge enrichment plant. The paper will describe the diversion scenarios analyzed and the effectiveness of various safeguards systems alternatives

  5. Enrichment situation outside the United States

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Different enrichment technologies are briefly characterized which include gaseous diffusion, which is presently the production mainstay of the United States and France; the gaseous centrifuge which is the production plant for Urenco and the technology for future United States enrichment expansion; the aero-dynamic processes which include the jet nozzle (also known as the Becker process) and the fixed-wall centrifuge (also known as the Helikon process); chemical processes; laser isotope separation processes (also referred to in the literature as LIS); and plasma technology

  6. Determination of the separation factor of uranium isotopes by gaseous diffusion

    International Nuclear Information System (INIS)

    Bilous, O.; Counas, G.

    1958-01-01

    A 12-stage pilot separation cascade with a low output has been constructed to measure the separation factor of uranium isotopes by gaseous diffusion. The report describes some of the separation results obtained, and also provides information on the time necessary for equilibrium to be established and on the influence of various perturbations on the pressure profile in the cascade. (author) [fr

  7. Safety aspects of gas centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Hansen, A.H.

    1987-01-01

    Uranium enrichment by gas centrifuge is a commercially proven, viable technology. Gas centrifuge enrichment plant operations pose hazards that are also found in other industries as well as unique hazards as a result of processing and handling uranium hexafluoride and the handling of enriched uranium. Hazards also found in other industries included those posed by the use of high-speed rotating equipment and equipment handling by use of heavy-duty cranes. Hazards from high-speed rotating equipment are associated with the operation of the gas centrifuges themselves and with the operation of the uranium hexafluoride compressors in the tail withdrawal system. These and related hazards are discussed. It is included that commercial gas centrifuge enrichment plants have been designed to operate safely

  8. Uranium enrichment

    International Nuclear Information System (INIS)

    Rae, H.K.; Melvin, J.G.

    1988-06-01

    Canada is the world's largest producer and exporter of uranium, most of which is enriched elsewhere for use as fuel in LWRs. The feasibility of a Canadian uranium-enrichment enterprise is therefore a perennial question. Recent developments in uranium-enrichment technology, and their likely impacts on separative work supply and demand, suggest an opportunity window for Canadian entry into this international market. The Canadian opportunity results from three particular impacts of the new technologies: 1) the bulk of the world's uranium-enrichment capacity is in gaseous diffusion plants which, because of their large requirements for electricity (more than 2000 kW·h per SWU), are vulnerable to competition from the new processes; 2) the decline in enrichment costs increases the economic incentive for the use of slightly-enriched uranium (SEU) fuel in CANDU reactors, thus creating a potential Canadian market; and 3) the new processes allow economic operation on a much smaller scale, which drastically reduces the investment required for market entry and is comparable with the potential Canadian SEU requirement. The opportunity is not open-ended. By the end of the century the enrichment supply industry will have adapted to the new processes and long-term customer/supplier relationships will have been established. In order to seize the opportunity, Canada must become a credible supplier during this century

  9. Aerodynamic effects in isotope separation by gaseous diffusion

    International Nuclear Information System (INIS)

    Bert, L.A.; Prosperetti, A.; Fiocchi, R.

    1978-01-01

    The turbulent flow of an isotopic mixture in a porous-walled pipe is considered in the presence of suction through the wall. A simple model is formulated for the evaluation of aerodynamic effects on the separation efficiency. The predictions of the model are found to compare very favourably with experiment. In the limit of small suction velocities, results obtained by other investigators for diffusion in a turbulent steam are recovered. (author)

  10. France makes steady progress with lasers [enrichment

    International Nuclear Information System (INIS)

    Coates, J.-H.; Clerc, M.; Plurien, P.

    1988-01-01

    With the CHEMEX process now a commercially available technology, the French Commissariat a l'Energie (CEA) is focussing its R and D activity on two enrichment processes: gaseous diffusion, and atomic vapour laser isotope separation (AVLIS or SILVA). The SILVA process is being developed, with particular attention being paid to test campaigns undertaken on the pilot unit installed at Saclay. A core of technical know-how is being maintained in gaseous diffusion in order to study the behaviour of, and possible improvements to, the newly named George Besse plant at the Tricastin site. (U.K.)

  11. Uranium enrichment in the United States

    International Nuclear Information System (INIS)

    Hill, J.H.; Parks, J.W.

    1975-01-01

    History, improvement programs, status of electrical power availability, demands for uranium enrichment, operating plan for the U. S. enriching facilities, working inventory of enriched uranium, possible factors affecting deviations in the operating plan, status of gaseous diffusion technology, status of U. S. gas centrifuge advances, transfer of enrichment technology, gaseous diffusion--gas centrifuge comparison, new enrichment capacity, U. S. separative work pricing, and investment in nuclear energy are discussed. (LK)

  12. Diffusion coefficients of gaseous scavengers in organic liquids used in radiation chemistry

    International Nuclear Information System (INIS)

    Luthjens, L.H.; De Leng, H.C.; Warman, J.M.; Hummel, A.

    1990-01-01

    Diffusion coefficients have been measured of some gaseous scavengers commonly used in radiation chemical studies: CO 2 , NH 3 , SF 6 and O 2 in trans-decalin, cyclohexane, isooctane and n-hexane, and CO 2 in cis-decalin, at 25 0 C. A modified diaphragm cell method has been used in order to limit the time needed for a measurement to about 6 h. Analysis of the results yields a simple semi-empirical predictive relation for the diffusion coefficient of a (gaseous) solute A in an organic solvent B. Diffusion coefficients calculated using the simple relation appear to give results in fair agreement with published values, over a range of organic solvents including alcohols, and over a range of temperatures. Some measured and predicted values are discussed with reference to results from the literature. (author)

  13. Portsmouth Gasseous Diffusion Plant site, Piketon, Ohio. Final environmental impact statement. Volume 1

    International Nuclear Information System (INIS)

    1977-05-01

    This environmental statement provides a detailed analysis of the environmental effects associated with continued operation of the Portsmouth Gaseous Diffusion Plant, one of the three government-owned uranium enrichment plants operated by the Energy Research and Development Administration (ERDA). The Portsmouth facility, which has been operating for over twenty years, is located in Pike County, Ohio, on a 4000-acre federally owned reservation. The uranium enrichment capacity of the plant is currently being increased through a cascade improvement program (CIP) and a cascade uprating program (CUP). This environmental statement evaluates the Portsmouth facility at the fully uprated CUP production level. Environmental impacts of the production of offsite electric power for the Portsmouth facility are also assessed. The bulk of this power is supplied by the Ohio Valley Electric Corporation (OVEC) from two coal-fired plants, the Clifty Creek Power Plant near Madison, Indiana, and the Kyger Creek Power Plant near Cheshire, Ohio. The remaining required power will be obtained on a system basis through OVEC from the 15 sponsoring utilities of OVEC. The draft statement was issued for public comment on February 15, 1977, and public hearing to afford the public further opportunity to comment was held in Cincinnati, Ohio, on April 5, 1977

  14. Direct measurement of gaseous activities by diffusion-in long proportional counter method

    International Nuclear Information System (INIS)

    Yoshida, M.; Yamamoto, T.; Wu, Y.; Aratani, T.; Uritani, A.; Mori, C.

    1993-01-01

    Direct measurement of gaseous activities by the diffusion-in long proportional counter method (DLPC method) was studied. The measuring time without end effect was estimated by observing the behavior of 37 Ar in the counter and was long enough to carry out the accurate activity measurement. The correction for wall effect was also examined on the basis of the measured and calculated correction factors. Among the tested gases of methane, P10 gas and propane, P10 gas was made clear to be a suitable counting gas for the DLPC method because of good diffusion properties and small wall effect. This method is quite effective for standardization of gaseous activities used for tracer experiments and calibration works of radioactive gas monitoring instruments. (orig.)

  15. A novel enhanced diffusion sampler for collecting gaseous pollutants without air agitation.

    Science.gov (United States)

    Pan, Xuelian; Zhuo, Shaojie; Zhong, Qirui; Chen, Yuanchen; Du, Wei; Cheng, Hefa; Wang, Xilong; Zeng, Eddy Y; Xing, Baoshan; Tao, Shu

    2018-03-06

    A novel enhanced diffusion sampler for collecting gaseous phase polycyclic aromatic hydrocarbons (PAHs) without air agitation is proposed. The diffusion of target compounds into a sampling chamber is facilitated by continuously purging through a closed-loop flow to create a large concentration difference between the ambient air and the air in the sampling chamber. A glass-fiber filter-based prototype was developed. It was demonstrated that the device could collect gaseous PAHs at a much higher rate (1.6 ± 1.4 L/min) than regular passive samplers, while the ambient air is not agitated. The prototype was also tested in both the laboratory and field for characterizing the concentration gradients over a short distance from the soil surface. The sampler has potential to be applied in other similar situations to characterize the concentration profiles of other chemicals.

  16. Acoustic pressure amplitude thresholds for rectified diffusion in gaseous microbubbles in biological tissue

    DEFF Research Database (Denmark)

    Lewin, Peter A.; Jensen, Leif Bjørnø

    1981-01-01

    One of the mechanisms often suggested for the biological action of ultrasonic beams irradiating human tissues is concerned with the presence in the tissues of minute gaseous bubbles which may, under the influence of the ultrasonic field be stimulated to grow to a size at which resonance or collap...... of calculations for typical (transient) exposure conditions from pulse-echo equipment are presented, indicating that rectified diffusion and stable cavitation are improbable phenomena in these circumstances....

  17. Uranium enrichment. Enrichment processes

    International Nuclear Information System (INIS)

    Alexandre, M.; Quaegebeur, J.P.

    2009-01-01

    Despite the remarkable progresses made in the diversity and the efficiency of the different uranium enrichment processes, only two industrial processes remain today which satisfy all of enriched uranium needs: the gaseous diffusion and the centrifugation. This article describes both processes and some others still at the demonstration or at the laboratory stage of development: 1 - general considerations; 2 - gaseous diffusion: physical principles, implementation, utilisation in the world; 3 - centrifugation: principles, elementary separation factor, flows inside a centrifuge, modeling of separation efficiencies, mechanical design, types of industrial centrifuges, realisation of cascades, main characteristics of the centrifugation process; 4 - aerodynamic processes: vortex process, nozzle process; 5 - chemical exchange separation processes: Japanese ASAHI process, French CHEMEX process; 6 - laser-based processes: SILVA process, SILMO process; 7 - electromagnetic and ionic processes: mass spectrometer and calutron, ion cyclotron resonance, rotating plasmas; 8 - thermal diffusion; 9 - conclusion. (J.S.)

  18. Safeguards for reprocessing and enrichment plants

    International Nuclear Information System (INIS)

    1977-01-01

    Agency safeguards are entering a new phase with the coming under active safeguards for the first time of reprocessing plants in several regions of the world. This is taking place at a time when not only the safeguards aspect itself is coming under international scrutiny, but also at a time when the necessity of reprocessing plants is being called into question. Attracting less attention at the moment, but potentially of equal significance, are the enrichment plants that soon will be coming under Agency safeguards. It is not unreasonable in view of the present controversies to ask what is the significance of these reprocessing and enrichment plants, what are the problems concerning safeguards that appear to have given rise to the controversies, and how these problems are to be solved. The question of significance is an easy one to answer. The output of these plants is material which some people consider can be used directly for military purposes, whereas the output from other plants, for instance, reactors, would require long and extensive processing before it could be used for military purposes. Like most short answers, this one is an over-simplification which requires some elaboration to make it strictly accurate. For example, the material output of a power reactor is in the form of irradiate assemblies containing plutonium which is potentially of military use if the irradiation had been within a certain range. However, to utilize this plutonium under clandestine conditions, the highly radioactive material would have to be secretly transported to a reprocessing plant and there would have to be simultaneous falsification of the reactor material accounts and the plant records. Such falsification would be difficult to conceal. The total time required to obtain usable plutonium would be many months. Diversion of material from a uranium fabrication plant making fuel for power reactors would be easier physically but strategically it would be of little value. The

  19. Integrated design of SIGMA uranium enrichment plants

    International Nuclear Information System (INIS)

    Rivarola, Martin E.; Brasnarof, Daniel O.

    1999-01-01

    In the present work, we describe a preliminary analysis of the design feedbacks in a Uranium Enrichment Plant, using the SIGMA concept. Starting from the result of this analysis, a computer code has been generated, which allows finding the optimal configurations of plants, for a fixed production rate. The computer code developed includes the model of the Thermohydraulic loop of a SIGMA module. The model contains numerical calculations of the main components of the circuit. During the calculations, the main components are dimensioned, for a posterior cost compute. The program also makes an estimation of the enrichment gain of the porous membrane, for each separation stage. Once the dimensions of the main components are known, using the enrichment cascade calculation, the capital and operation costs of the plant could be determined. At this point it is simple to calculate a leveled cost of the Separative Work Unit (SWU). A numerical optimizer is also included in the program. This optimizer finds the optimal cascade configuration, for a given set of design parameters. The whole-integrated program permits to investigate in detail the feedback in the component design. Therefore, the sensibility of the more relevant parameters can be computed, with respect of the economical variables of the plant. (author)

  20. Enrichment: Dealing with overcapacity

    International Nuclear Information System (INIS)

    Peterson, C.H.

    1989-01-01

    Today's surplus of enrichment capacity will continue until at least the end of this century. This will challenge the ingenuity of the separative work unit (SWU) suppliers as they attempt to keep market share and remain profitable in a very competitive marketplace. The utilities will be faced with attractive choices, but making the best choice will require careful analysis and increased attention to market factors. Current demand projections will probably prove too high to the extent that more reactors are canceled or delayed. The DOE has the vast majority of the unused capacity, so it will feel the most immediate impact of this large surplus in productive capacity. The DOE has responded to these market challenges by planning another reorganization of its enriching operations. Without a major agreement among the governments affected by the current surplus in enrichment capacity, the future will see lower prices, more competitive terms, and the gradual substitution of centrifuge or laser enrichment for the gaseous diffusion plants. The competition that is forcing the gaseous diffusion prices down to marginal cost will provide the long-term price basis for the enrichment industry

  1. SIGMA: the novel approach of a new non-proliferating uranium enrichment technology

    International Nuclear Information System (INIS)

    Rivarola, M.; Florido, P.; Brasnarof, D.; Bergallo, E.

    2000-01-01

    The SIGMA concept, under development by Argentina, represents the evolution of the Uranium Enrichment Gaseous Diffusion technology, updated to face the challenge of the new economic-based and competitive world frame. The Enrichment technology has been historically considered as a highly proliferating activity in the nuclear field, and central countries limited the access of the developing countries to this technology. The SIGMA concept incorporates innovative proliferation resistant criteria at the beginning of the design process, and inherits all the non-proliferation features of the gaseous diffusion plants (GDPs). The radical new proliferation resistance approach of the SIGMA technology suggests a new kind of global control of the uranium enrichment market, where some developing countries might access an Enrichment plant without access to the technology itself. In this paper, we investigate the economy of the SIGMA plants, and the implications of this technology on the Uranium Global Market. (authors)

  2. SIGMA, the novel approach of a new non-proliferating uranium enrichment technology

    International Nuclear Information System (INIS)

    Rivarola, M.; Florido, P.; Brasnarof, D.; Bergallo, J.

    2001-01-01

    The SIGMA concept, under development by Argentina, represents the evolution of the Uranium Enrichment Gaseous Diffusion technology, updated to face the challenge of the new economic-based and competitive world frame. The Enrichment technology has been historically considered as a highly proliferating activity in the nuclear field, and central countries have limited the access of the developing countries to this technology. The SIGMA concept incorporates innovative proliferation resistant criteria at the beginning of the design process, and inherits all the non-proliferation features of the Gaseous Diffusion Plants (GDPs). The radical new proliferation resistant approach of the SIGMA technology, suggest a new kind of global control of the Uranium Enrichment Market, were some developing countries might access to an Enrichment plant without accessing to the technology itself. In this paper, we analyse the economy of the SIGMA plants, and the implications of this technology on the Uranium Global Market. (authors)

  3. Economic evaluation of laser enrichment plant

    International Nuclear Information System (INIS)

    Arisawa, Takashi; Shiba, Koreyuki

    1983-08-01

    Operational characteristics of Laser Enrichment Plant are described based on the data available at present. And its economy is also discussed from the view point of investment and energy consumption. In the procedure of this estimation, the composition of the plant is firstly considered, secondly each component is designed, and thirdly the production cost of each component is estimated. Then the sensitivity of the component cost on the plant cost is analysed, which leads to the optimization of the product cost and the determination of the economic plant size, etc. The results shows that the power cost of the electric gun occupies the large majority of the total power cost, and that the capital cost of laser devices occupies most of the total capital cost. (author)

  4. A random walk approach to the diffusion of positrons in gaseous media

    International Nuclear Information System (INIS)

    Girardi-Schappo, M.; Tenfen, W.; Arretche, F.

    2013-01-01

    In this work, we present a random walk model to study the positron diffusion in gaseous media. The positron-atom interaction is described through positron-target cross sections. The main idea is to obtain how much energy a positron transfer to the environment atoms, through ionizations and electronic excitations until its annihilation, taking the ratio between each energetically available collision channel to the total one as the probability for each process to occur. As a first application, we studied how the positron diffuse in gases of helium, neon, argon and their mixtures. To characterize the positron dynamics in each system, we calculated the radiation profile generated from the annihilation, their diffusion profiles and the most probable distances for excitation and ionization. (authors)

  5. Gas-phase UF6 enrichment monitor for enrichment plant safeguards

    International Nuclear Information System (INIS)

    Strittmatter, R.B.; Tape, J.W.

    1980-03-01

    An in-line enrichment monitor is being developed to provide real-time enrichment data for the gas-phase UF 6 feed stream of an enrichment plant. The nondestructive gamma-ray assay method can be used to determine the enrichment of natural UF 6 with a relative precision of better than 1% for a wide range of pressures

  6. Self-diffusion in isotopically enriched silicon carbide and its correlation with dopant diffusion

    International Nuclear Information System (INIS)

    Rueschenschmidt, K.; Bracht, H.; Stolwijk, N.A.; Laube, M.; Pensl, G.; Brandes, G.R.

    2004-01-01

    Diffusion of 13 C and 30 Si in silicon carbide was performed with isotopically enriched 4H- 28 Si 12 C/ nat SiC heterostructures which were grown by chemical vapor phase epitaxy. After diffusion annealing at temperatures between 2000 deg. C and 2200 deg. C the 30 Si and 13 C profiles were measured by means of secondary ion mass spectrometry. We found that the Si and C diffusivity is of the same order of magnitude but several orders of magnitude lower than earlier data reported in the literature. Both Si and C tracer diffusion coefficients are in satisfactory agreement with the native point defect contribution to self-diffusion deduced from B diffusion in SiC. This reveals that the native defect which mediates B diffusion also controls self-diffusion. Assuming that B atoms within the extended tail region of B profiles are mainly dissolved on C sites, we propose that B diffuses via the kick-out mechanism involving C interstitials. Accordingly, C diffusion should proceed mainly via C interstitials. The mechanism of Si diffusion remains unsolved but Si may diffuse via both Si vacancies and interstitials, with the preference for either species depending on the doping level

  7. Tc-99 Decontamination From Heat Treated Gaseous Diffusion Membrane -Phase I

    Energy Technology Data Exchange (ETDEWEB)

    Oji, L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Wilmarth, B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Restivo, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Duignan, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-03-13

    Uranium gaseous diffusion cascades represent a significant environmental challenge to dismantle, containerize and dispose as low-level radioactive waste. Baseline technologies rely on manual manipulations involving direct access to technetium-contaminated piping and materials. There is a potential to utilize novel thermal decontamination technologies to remove the technetium and allow for on-site disposal of the very large uranium converters. Technetium entered these gaseous diffusion cascades as a hexafluoride complex in the same fashion as uranium. Technetium, as the isotope Tc-99, is an impurity that follows uranium in the first cycle of the Plutonium and Uranium Extraction (PUREX) process. The technetium speciation or exact form in the gas diffusion cascades is not well defined. Several forms of Tc-99 compounds, mostly the fluorinated technetium compounds with varying degrees of volatility have been speculated by the scientific community to be present in these cascades. Therefore, there may be a possibility of using thermal desorption, which is independent of the technetium oxidation states, to perform an in situ removal of the technetium as a volatile species and trap the radionuclide on sorbent traps which could be disposed as low-level waste.

  8. TC-99 Decontaminant from heat treated gaseous diffusion membrane -Phase I, Part B

    Energy Technology Data Exchange (ETDEWEB)

    Oji, L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Restivo, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Duignan, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Wilmarth, B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-11-01

    Uranium gaseous diffusion cascades represent a significant environmental challenge to dismantle, containerize and dispose as low-level radioactive waste. Baseline technologies rely on manual manipulations involving direct access to technetium-contaminated piping and materials. There is a potential to utilize novel decontamination technologies to remove the technetium and allow for on-site disposal of the very large uranium converters. Technetium entered these gaseous diffusion cascades as a hexafluoride complex in the same fashion as uranium. Technetium, as the isotope Tc-99, is an impurity that follows uranium in the first cycle of the Plutonium and Uranium Extraction (PUREX) process. The technetium speciation or exact form in the gaseous diffusion cascades is not well defined. Several forms of Tc-99 compounds, mostly the fluorinated technetium compounds with varying degrees of volatility have been speculated by the scientific community to be present in these cascades. Therefore, there may be a possibility of using thermal or leaching desorption, which is independent of the technetium oxidation states, to perform an insitu removal of the technetium as a volatile species and trap the radionuclide on sorbent traps which could be disposed as low-level waste. Based on the positive results of the first part of this work1 the use of steam as a thermal decontamination agent was further explored with a second piece of used barrier material from a different location. This new series of tests included exposing more of the material surface to the flow of high temperature steam through the change in the reactor design, subjecting it to alternating periods of stream and vacuum, as well as determining if a lower temperature steam, i.e., 121°C (250°F) would be effective, too. Along with these methods, one other simpler method involving the leaching of the Tc-99 contaminated barrier material with a 1.0 M aqueous solution of ammonium carbonate, with and without sonication, was

  9. Using Process Load Cell Information for IAEA Safeguards at Enrichment Plants

    International Nuclear Information System (INIS)

    Laughter, Mark D.; Whitaker, J. Michael; Howell, John

    2010-01-01

    Uranium enrichment service providers are expanding existing enrichment plants and constructing new facilities to meet demands resulting from the shutdown of gaseous diffusion plants, the completion of the U.S.-Russia highly enriched uranium downblending program, and the projected global renaissance in nuclear power. The International Atomic Energy Agency (IAEA) conducts verification inspections at safeguarded facilities to provide assurance that signatory States comply with their treaty obligations to use nuclear materials only for peaceful purposes. Continuous, unattended monitoring of load cells in UF 6 feed/withdrawal stations can provide safeguards-relevant process information to make existing safeguards approaches more efficient and effective and enable novel safeguards concepts such as information-driven inspections. The IAEA has indicated that process load cell monitoring will play a central role in future safeguards approaches for large-scale gas centrifuge enrichment plants. This presentation will discuss previous work and future plans related to continuous load cell monitoring, including: (1) algorithms for automated analysis of load cell data, including filtering methods to determine significant weights and eliminate irrelevant impulses; (2) development of metrics for declaration verification and off-normal operation detection ('cylinder counting,' near-real-time mass balancing, F/P/T ratios, etc.); (3) requirements to specify what potentially sensitive data is safeguards relevant, at what point the IAEA gains on-site custody of the data, and what portion of that data can be transmitted off-site; (4) authentication, secure on-site storage, and secure transmission of load cell data; (5) data processing and remote monitoring schemes to control access to sensitive and proprietary information; (6) integration of process load cell data in a layered safeguards approach with cross-check verification; (7) process mock-ups constructed to provide simulated load

  10. Lessons-Learned from D and D Activities at the Five Gaseous Diffusion Buildings (K-25, K- 27, K-29, K-31 and K-33) East Tennessee Technology Park, Oak Ridge, TN - 13574

    International Nuclear Information System (INIS)

    Kopotic, James D.; Ferri, Mark S.; Buttram, Claude

    2013-01-01

    The East Tennessee Technology Park (ETTP) is the site of five former gaseous diffusion plant (GDP) process buildings that were used to enrich uranium from 1945 to 1985. The process equipment in the original two buildings (K-25 and K-27) was used for the production of highly enriched uranium (HEU), while that in the three later buildings (K-29, K-31 and K-33) produced low enriched uranium (LEU). Equipment was contaminated primarily with uranium and to a lesser extent technetium (Tc). Decommissioning of the GDP process buildings has presented several unique challenges and produced many lessons-learned. Among these is the importance of good, up-front characterization in developing the best demolition approach. Also, chemical cleaning of process gas equipment and piping (PGE) prior to shutdown should be considered to minimize the amount of hold-up material that must be removed by demolition crews. Another lesson learned is to maintain shutdown buildings in a dry state to minimize structural degradation which can significantly complicate characterization, deactivation and demolition efforts. Perhaps the most important lesson learned is that decommissioning GDP process buildings is first and foremost a waste logistics challenge. Innovative solutions are required to effectively manage the sheer volume of waste generated from decontamination and demolition (D and D) of these enormous facilities. Finally, close coordination with Security is mandatory to effectively manage Special Nuclear Material (SNM) and classified equipment issues. (authors)

  11. Lessons-Learned from D and D Activities at the Five Gaseous Diffusion Buildings (K-25, K- 27, K-29, K-31 and K-33) East Tennessee Technology Park, Oak Ridge, TN - 13574

    Energy Technology Data Exchange (ETDEWEB)

    Kopotic, James D. [United States Department of Energy, Oak Ridge Office, P.O. Box 2001, Oak Ridge, TN 37831 (United States); Ferri, Mark S.; Buttram, Claude [URS - CH2M Oak Ridge LLC, East Tennessee Technology Park, P. O. Box 4699, Oak Ridge, TN 37831 (United States)

    2013-07-01

    The East Tennessee Technology Park (ETTP) is the site of five former gaseous diffusion plant (GDP) process buildings that were used to enrich uranium from 1945 to 1985. The process equipment in the original two buildings (K-25 and K-27) was used for the production of highly enriched uranium (HEU), while that in the three later buildings (K-29, K-31 and K-33) produced low enriched uranium (LEU). Equipment was contaminated primarily with uranium and to a lesser extent technetium (Tc). Decommissioning of the GDP process buildings has presented several unique challenges and produced many lessons-learned. Among these is the importance of good, up-front characterization in developing the best demolition approach. Also, chemical cleaning of process gas equipment and piping (PGE) prior to shutdown should be considered to minimize the amount of hold-up material that must be removed by demolition crews. Another lesson learned is to maintain shutdown buildings in a dry state to minimize structural degradation which can significantly complicate characterization, deactivation and demolition efforts. Perhaps the most important lesson learned is that decommissioning GDP process buildings is first and foremost a waste logistics challenge. Innovative solutions are required to effectively manage the sheer volume of waste generated from decontamination and demolition (D and D) of these enormous facilities. Finally, close coordination with Security is mandatory to effectively manage Special Nuclear Material (SNM) and classified equipment issues. (authors)

  12. Criticality analysis in uranium enrichment plant

    International Nuclear Information System (INIS)

    Okamoto, Tsuyoshi; Kiyose, Ryohei

    1977-01-01

    In a large scale uranium enrichment plant, uranium inventory in cascade rooms is not very large in quantity, but the facilities dealing with the largest quantity of uranium in that process are the UF 6 gas supply system and the blending system for controlling the product concentration. When UF 6 spills out of these systems, the enriched uranium is accumulated, and the danger of criticality accident is feared. If a NaF trap is placed at the forestage of waste gas treatment system, plenty of UF 6 and HF are adsorbed together in the NaF trap. Thus, here is the necessity of checking the safety against criticality. Various assumptions were made to perform the computation surveying the criticality of the system composed of UF 6 and HF adsorbed on NaF traps with WIMS code (transport analysis). The minimum critical radius resulted in about 53 cm in case of 3.5% enriched fuel for light water reactors. The optimum volume ratio of fissile material in the double salt UF 6 .2NaF and NaF.HF is about 40 vol. %. While, criticality survey computation was also made for the annular NaF trap having the central cooling tube, and it was found that the effect of cooling tube radius did not decrease the multiplication factor up to the cooling tube radius of about 5 cm. (Wakatsuki, Y.)

  13. General productivity code: productivity optimization of gaseous diffusion cascades. The programmer's guide

    International Nuclear Information System (INIS)

    Tunstall, J.N.

    1975-05-01

    The General Productivity Code is a FORTRAN IV computer program for the IBM System 360. With its model of the productivity of gaseous diffusion cascades, the program is used to determine optimum cascade performance based on specified operating conditions and to aid in the calculation of optimum operating conditions for a complex of diffusion cascades. This documentation of the program is directed primarily to programmers who will be responsible for updating the code as requested by the users. It is also intended to be an aid in training new Productivity Code users and to serve as a general reference manual. Elements of the mathematical model, the input data requirements, the definitions of the various tasks (Instructions) that can be performed, and a detailed description of most FORTRAN variables and program subroutines are presented. A sample problem is also included. (auth)

  14. Direct estimation of diffuse gaseous emissions from coal fires: current methods and future directions

    Science.gov (United States)

    Engle, Mark A.; Olea, Ricardo A.; O'Keefe, Jennifer M. K.; Hower, James C.; Geboy, Nicholas J.

    2013-01-01

    Coal fires occur in nature spontaneously, contribute to increases in greenhouse gases, and emit atmospheric toxicants. Increasing interest in quantifying coal fire emissions has resulted in the adaptation and development of specialized approaches and adoption of numerical modeling techniques. Overview of these methods for direct estimation of diffuse gas emissions from coal fires is presented in this paper. Here we take advantage of stochastic Gaussian simulation to interpolate CO2 fluxes measured using a dynamic closed chamber at the Ruth Mullins coal fire in Perry County, Kentucky. This approach allows for preparing a map of diffuse gas emissions, one of the two primary ways that gases emanate from coal fires, and establishing the reliability of the study both locally and for the entire fire. Future research directions include continuous and automated sampling to improve quantification of gaseous coal fire emissions.

  15. Gaseous waste processing device in nuclear power plant

    International Nuclear Information System (INIS)

    Takechi, Eisuke; Matsutoshi, Makoto.

    1978-01-01

    Purpose: To arrange the units of waste processing devices in a number one more than the number thereof required for a plurality of reactors, and to make it usable commonly as a preliminary waste processing device thereby to effectively use all the gaseous waste processing devices. Constitution: A gaseous waste processing device is constituted by an exhaust gas extractor, a first processing device, a second processing device and the like, which are all connected in series. Upon this occasion, devices from the exhaust gas extractor to the first processing device and valves, which are provided in each of reactors, are arranged in series, on one hand, but valves at the downstream side join one another by one pipeline, and are connected to a stack through a total gaseous waste processing device, on another. (Yoshihara, H.)

  16. The SIGMA plants economic behavior

    International Nuclear Information System (INIS)

    Rivarola, Martin E.; Bergallo, Juan E.

    1999-01-01

    In this work, the economical behavior of the Uranium Enrichment Plants, built using the Gaseous Isotopic Separation using Advanced Methods (SIGMA) (Separacion Isotopica Gaseosa por Metodos Avanzados) technology is analyzed. The calculations were made using an integrated computer code, where the cost of each main component of the plant is estimated. The program computes the production cost for several configurations of enrichment cascades, each one corresponding to a production rate. The program also includes a numerical optimizer and it seeks the SIGMA optimal configuration for a given set of design parameters. The present work does not contemplate the model and calculation of the auxiliary system costs. The total amortization cost is obtained by using the cascade capital cost and assuming that the auxiliary system represents a fixed part of the total cost.The results obtained show that the SIGMA technology for Enrichment Uranium Plants could achieve economical competition in a much lower production scale than the conventional Gaseous Diffusion Enrichment Plants. (author)

  17. Application of safeguards techniques to the Eurodif gas diffusion plant

    International Nuclear Information System (INIS)

    Coates, J.H.; Goens, J.R.

    1979-01-01

    The characteristic features of gas diffusion plants are such that safeguards procedures specifically suited for this technique can be proposed. The first of these features is the fact that appreciably altering the enrichment level of the plant product is not possible without making easily detectable changes either in the plant structure itself or in the movement of incoming and outgoing materials. Furthermore, because of the size of gas diffusion plants large stocks of uranium are present in them. Although inventory differences may be small in relative terms, they are large in abosolute terms and exceed the quantities of low-enriched uranium considered significant from the standpoint of safeguards. Lastly, the impossibility for economic reasons for taking a physical inventory of the plant after it has been emptied prevents a comparison of the physical inventory with the book inventory. It would therefore seem that the safeguarding of a gas diffusion plant should be focused on the movement of nuclear material between the plant and the outside world. The verification of inputs and outputs can be considered satisfactory from the safeguards standpoint as long as it is possible to make sure of the containment of the plant and of the surveillance for the purpose of preventing clandestine alterations of structure. The description of the Eurodif plant and the movement of materials planned there at present indicate that the application of such a safeguards technique to the plant should be acceptable to the competent authorities. For this purpose a monitoring area has been set aside in which the inspectors will be able to keep track of all movements between the outside world and the enrichment plant

  18. Ningyo Toge uranium enrichment pilot plant comes into full

    International Nuclear Information System (INIS)

    1982-01-01

    The uranium enrichment pilot plant of the Power Reactor and Nuclear Fuel Development Corporation at Ningyo Toge went into full operation on March 26, 1982. This signifies that the front end of the nuclear fuel cycle in Japan, from uranium ore to enrichment, is only a step away from commercialization. On the same day, the pilot plant of uranium processing and conversion to UF 6 , the direct purification of uranium ore into uranium hexafluoride, began batch operation at the same works. The construction of the uranium enrichment pilot plant has been advanced in three stages: i.e. OP-1A with 1000 centrifuges, OP-1B with 3000 centrifuges and OP-2 with 3000 centrifuges. With a total of 7000 centrifuges, the pilot plant, the first enrichment plant in Japan, has now a capacity of supplying enriched uranium for six months operation of a 1,000 MW nuclear power plant. (J.P.N.)

  19. Evaluation of economical at a uranium enrichment demonstration plant

    International Nuclear Information System (INIS)

    Sugitsue, Noritake

    2001-01-01

    In this report, the economy of technical achievement apply in the uranium enrichment demonstration plant is evaluated. From the evaluation, it can be concluded that the expected purpose was achieved because there was a definite economic prospect to commercial plant. The benefit analysis of thirteen years operation of the uranium enrichment demonstration plant also provides a financial aspect of the uranium enrichment business. Therefore, the performance, price and reliability of the centrifuge is an important factor in the uranium enrichment business. And the continuous development of a centrifuge while considering balance with the development cost is necessary for the business in the future. (author)

  20. Preliminary study of the economics of enriching PWR fuel with a fusion hybrid reactor

    International Nuclear Information System (INIS)

    Kelly, J.L.

    1978-09-01

    This study is a comparison of the economics of enriching uranium oxide for pressurized water reactor (PWR) power plant fuel using a fusion hybrid reactor versus the present isotopic enrichment process. The conclusion is that privately owned hybrid fusion reactors, which simultaneously produce electrical power and enrich fuel, are competitive with the gaseous diffusion enrichment process if spent PWR fuel rods are reenriched without refabrication. Analysis of irradiation damage effects should be performed to determine if the fuel rod cladding can withstand the additional irradiation in the hybrid and second PWR power cycle. The cost competitiveness shown by this initial study clearly justifies further investigations

  1. Analysis and evalaution in the production process and equipment area of the low-cost solar array project. [including modifying gaseous diffusion and using ion implantation

    Science.gov (United States)

    Goldman, H.; Wolf, M.

    1979-01-01

    The manufacturing methods for photovoltaic solar energy utilization are assessed. Economic and technical data on the current front junction formation processes of gaseous diffusion and ion implantation are presented. Future proposals, including modifying gaseous diffusion and using ion implantation, to decrease the cost of junction formation are studied. Technology developments in current processes and an economic evaluation of the processes are included.

  2. Uranium enrichment

    International Nuclear Information System (INIS)

    Mohrhauer, H.

    1982-01-01

    The separation of uranium isotopes in order to enrich the fuel for light water reactors with the light isotope U-235 is an important part of the nuclear fuel cycle. After the basic principals of isotope separation the gaseous diffusion and the centrifuge process are explained. Both these techniques are employed on an industrial scale. In addition a short review is given on other enrichment techniques which have been demonstrated at least on a laboratory scale. After some remarks on the present situation on the enrichment market the progress in the development and the industrial exploitation of the gas centrifuge process by the trinational Urenco-Centec organisation is presented. (orig.)

  3. In situ gaseous tracer diffusion experiments and predictive modeling at the Greater Confinement Disposal Test

    International Nuclear Information System (INIS)

    Olson, M.C.

    1985-07-01

    The Greater Confinement Disposal Test (GCDT) at the Nevada Test Site is a research project investigating the feasibility of augered shaft disposal of low-level radioactive waste considered unsuitable for shallow land burial. The GCDT contains environmentally mobile and high-specific-activity sources. Research is focused on providing a set of analytically derived hydrogeologic parameters and an empirical database for application in a multiphase, two-dimensional, transient, predictive performance model. Potential contaminant transport processes at the GCDT are identified and their level of significance is detailed. Nonisothermal gaseous diffusion through alluvial sediments is considered the primary waste migration process. Volatile organic tracers are released in the subsurface and their migration is monitored in situ to determine media effective diffusion coefficients, tortuosity, and sorption-corrected porosity terms. The theoretical basis for volatile tracer experiments is presented. Treatment of thermal and liquid flow components is discussed, as is the basis for eliminating several negligible transport processes. Interpretive techniques include correlation, power spectra, and least squares analysis, a graphical analytical solution, and inverse numerical modeling. Model design and application to the GCDT are discussed. GCDT structural, analytical, and computer facilities are detailed. The status of the current research program is reviewed, and temperature and soil moisture profiles are presented along with results of operational tests on the analytical system. 72 refs., 39 figs., 2 tabs

  4. Monitoring of released radioactive gaseous and liquid effluent at Rokkasho Reprocessing Plant

    International Nuclear Information System (INIS)

    Oka, M.; Keta, S.; Nagai, S.; Kano, M.; Ishihara, N.; Moriyama, T.; Ogaki, K.; Noda, K.

    2009-01-01

    Rokkasho Reprocessing Plant (RRP) Rokkasho Reprocessing Plant started its active tests with spent fuel at the end of March 2006. When spent fuels are sheared and dissolved, radioactive gaseous effluent and radioactive liquid effluent such as krypton-85, tritium, etc. are released into the environment. In order to limit the public dose as low as reasonably achievable in an efficient way, RRP removes radioactive material by evaporation, rinsing, filtering, etc., and then releases it through the main stack and the sea discharge pipeline that allow to make dispersion and dilution very efficiently. Also, concerning the radioactive gaseous and liquid effluent to be released into the environment, the target values of annual release have been defined in the Safety Rule based on the estimated annual release evaluated at the safety review of RRP. By monitoring the radioactive material in gaseous exhaust and liquid effluent RRP controls it not to exceed the target values. RRP reprocessed 430 tUpr of spent fuel during Active Test (March 2006 to October 2008). In this report, we report about: The outline of gaseous and liquid effluent monitoring. The amount of radioactive gaseous and liquid effluent during the active test. The performance of removal of radioactive materials in gaseous and liquid effluents. The impact on the public from radioactive effluents during the active test. (author)

  5. An automated solution enrichment system for uranium analysis

    International Nuclear Information System (INIS)

    Jones, S.A.; Sparks, R.; Sampson, T.; Parker, J.; Horley, E.; Kelly, T.

    1993-01-01

    An automated Solution Enrichment system (SES) for analysis of Uranium and U-235 isotopes in process samples has been developed through a joint effort between Los Alamos National Laboratory and Martin Marietta Energy systems, Portsmouth Gaseous Diffusion Plant. This device features an advanced robotics system which in conjuction with stabilized passive gamma-ray and X-ray fluorescence detectors provides for rapid, non-destructive analyses of process samples for improved special nuclear material accountability and process control

  6. Community Visions for the Paducah Gaseous Diffusion Plant Site

    Energy Technology Data Exchange (ETDEWEB)

    Ormsbee, Lindell e [Civil Engineering, Univ. of KY; Kipp, James A [Univ. of KY, Kentucky water research Institute

    2011-09-01

    This report focuses on assessing community preferences for the future use of the PGDP site, given the site's pending closure by US DOE. The project approach fostered interaction and engagement with the public based on lessons learned at other complex DOE environmental cleanup sites and upon the integration of a number of principles and approaches to public engagement from the Project Team's local, state, regional and international public engagement experience. The results of the study provide the community with a record of the diversity of values and preferences related to the environmental cleanup and future use of the site.

  7. Paducah Gaseous Diffusion Plant site environmental report for 1988

    International Nuclear Information System (INIS)

    Rogers, J.G.; Jett, T.G.

    1989-05-01

    Quantities of nonradiological chemical emissions are not included in this report this year. An addendum that will include the information will be published after the Superfund Amendments Reauthorization Act (SARA) Title III report is issued on July 1, 1989. When the addendum is published, probably in late July, a summary of the SARA Title III 313 report will be included. The SARA report provides the community with the opportunity to lean about estimated quantities of certain toxic chemicals used at a facility that are routinely or accidentally released into the environment. The addendum that will be published after the SARA report will summarize the SARA report and is expected to include some additional ''large quantity'' chemicals used or stored at the facilities that are not required to be reported by SARA Title III but are known to be emitted from the facilities. The addendum will not be all inclusive but will provide emissions information on the major chemical emissions to the air, water, or land from processes at the facilities

  8. Breached cylinder incident at the Portsmouth gaseous diffusion plant

    Energy Technology Data Exchange (ETDEWEB)

    Boelens, R.A. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

    1991-12-31

    On June 16, 1990, during an inspection of valves on partially depleted product storage cylinders, a 14-ton partially depleted product cylinder was discovered breached. The cylinder had been placed in long-term storage in 1977 on the top row of Portsmouth`s (two rows high) storage area. The breach was observed when an inspector noticed a pile of green material along side of the cylinder. The breach was estimated to be approximately 8- inches wide and 16-inches long, and ran under the first stiffening ring of the cylinder. During the continuing inspection of the storage area, a second 14-ton product cylinder was discovered breached. This cylinder was stacked on the bottom row in the storage area in 1986. This breach was also located adjacent to a stiffening ring. This paper will discuss the contributing factors of the breaching of the cylinders, the immediate response, subsequent actions in support of the investigation, and corrective actions.

  9. Air-surface exchange measurements of gaseous elemental mercury over naturally enriched and background terrestrial landscapes in Australia

    Directory of Open Access Journals (Sweden)

    G. C. Edwards

    2013-05-01

    Full Text Available This paper presents the first gaseous elemental mercury (GEM air-surface exchange measurements obtained over naturally enriched and background (−1 Hg terrestrial landscapes in Australia. Two pilot field studies were carried out during the Australian autumn and winter periods at a copper-gold-cobalt-arsenic-mercury mineral field near Pulganbar, NSW. GEM fluxes using a dynamic flux chamber approach were measured, along with controlling environmental parameters over three naturally enriched and three background substrates. The enriched sites results showed net emission to the atmosphere and a strong correlation between flux and substrate Hg concentration, with average fluxes ranging from 14 ± 1 ng m−2 h−1 to 113 ± 6 ng m−2 h−1. Measurements at background sites showed both emission and deposition. The average Hg flux from all background sites showed an overall net emission of 0.36 ± 0.06 ng m−2 h−1. Fluxes show strong relationships with temperature, radiation, and substrate parameters. A compensation point of 2.48, representative of bare soils was determined. For periods of deposition, dry deposition velocities ranged from 0.00025 cm s−1 to 0.0083 cm s−1 with an average of 0.0041 ± 0.00018 cm s−1, representing bare soil, nighttime conditions. Comparison of the Australian data to North American data suggests the need for Australian-specific mercury air-surface exchange data representative of Australia's unique climatic conditions, vegetation types, land use patterns and soils.

  10. Main results obtained in France in the development of the gaseous diffusion process for uranium isotope separation; Principaux resultats obtenus en France dans les etudes sur la separation des isotopes de l'uranium par diffusion gazeuse

    Energy Technology Data Exchange (ETDEWEB)

    Frejacques, C; Bilous, O; Dixmier, J; Massignon, D; Plurien, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The main problems which occur in the study of uranium isotope separation by the gaseous diffusion process, concern the development of the porous barrier, the corrosive nature of uranium hexafluoride and also the chemical engineering problems related to process design and the choice of best plant and stage characteristics. Porous barriers may be obtained by chemical attack of non porous media or by agglomeration of very fine powders. Examples of these two types of barriers are given. A whole set of measurement techniques were developed for barrier structure studies, to provide control and guidance of barrier production methods. Uranium hexafluoride reactivity and corrosive properties are the source of many difficult technological problems. A high degree of plant leak tightness must be achieved. This necessity creates a special problem in compressor bearing design. Barrier lifetime is affected by the corrosive properties of the gas, which may lead to a change of barrier structure with time. Barrier hexafluoride permeability measurements have helped to make a systematic study of this point. Finally an example of a plant flowsheet, showing stage types and arrangements and based on a minimisation of enriched product costs is also given as an illustration of some of the chemical engineering problems present. (author) [French] Les principaux problemes qui se sont poses dans l'etude de la separation des isotopes de l'uranium par diffusion gazeuse, sont ceux relatifs a l'obtention de barrieres poreuses, ceux lies a l'utilisation de l'hexafluorure d'uranium, enfin les problemes de genie chimique relatifs au procede et a l'agencement optimum des etages et des cascades entre elles. On peut obtenir des barrieres poreuses soit par attaque de membranes pleines, soit par agglomeration de poudres de petites dimensions. Des exemples de ces deux types de barrieres seront donnes. L'etude des proprietes de texture des barrieres obtenues, necessaire pour orienter les recherches de

  11. Permit issued for expansion of the Gronau uranium enrichment plant

    International Nuclear Information System (INIS)

    2005-01-01

    Over the next few years, the Gronau Uranium Enrichment Plant (UAG) will be able to raise its capacity in steps from 1 800 tonnes to 4 500 tonnes SWU per annum. This development in steps depends on the extent to which demand on the world market can be turned into contracts for Urenco. After a procedure taking more than six years to complete, Urenco Deutschland GmbH was issued the required permit by the North Rhine-Westphalian State Ministry for Transport, Energy, and Planning on February 14 this year. The permit was preceded by the drafting and examination of two safety reports of several hundred pages each, and of over 1 000 detailed documents. The application documents were examined by a large number of expert consultants and public authorities from all over Germany acting on behalf of the nuclear licensing authority. Urenco Ltd. sells enrichment services worldwide, at present holding a share of approx. 19% of the world market for uranium separative work. Although this world market is not going to grow for a foreseeable period of time, Urenco is expanding its capacities. This is based on the latest centrifuge technology characterized by extremely low power consumption and high availability. It replaces diffusion technology, which currently holds a share of approx. 40% of the world market. (orig.)

  12. The diffusion and deposition of the gaseous and solid alpha radionuclides/aerosols in air

    International Nuclear Information System (INIS)

    Danis, A.; Ciubotariu, M.; Oncescu, M.; Mocsy, I.

    1999-01-01

    The diffusion and deposition of gaseous and solids alpha radionuclides and aerosols in air are processes which implicate low element amounts and therefore their studies require the using of very accurate and sensitive analysis methods. The alpha track method meets these requirements. The used alpha radionuclides were: Rn-222, as gaseous radionuclide and its solid descendants genetically related as solid radionuclides and the descendants attached to different particles from air as alpha aerosols. All these radionuclides were obtained from a calibrated Ra-226 source. The source was included into an air tight device with a well known volume and used after 40 days when the Ra-226 and its alpha descendants were under radioactive equilibrium. The relative amount and activity of each decay product, at any duration, for any initial mass of Ra-226 parent radionuclide, were calculated using a programme for computation of the U-238 radioactive series gamma accumulation, UURASE, adapted for alpha accumulation as ALFAURASE programme. The radon, Rn-222, as well as the solid alpha radionuclides and aerosols were measured using a new alpha monitoring device with or without paper filter for solid radionuclides and aerosols stopping. The track detectors of CR-39 type were incorporated with these monitoring devices. In order to calibrate the CR-39 detectors, a radon intercomparison programme was established with the participation of the SSNTD group from the Institute of Nuclear Research ATOMKI, Debrecen, Hungary, Institute of Public Health, Cluj-Napoca and SSNTD research group from IFIN-HH. We have used for radon calibration a special experimental device and a Ra-226 source. Using an air tight diffusion and deposition device, coupled with the source device, the concentration of radon and solid alpha radionuclides and aerosols were determined using the alpha track method. The alpha monitoring devices were fixed vertically at different distances from the place of radon penetration into

  13. 76 FR 53494 - In the Matter of United States Enrichment Corporation; Paducah Gaseous Enrichment Plant...

    Science.gov (United States)

    2011-08-26

    ... be filed in accordance with the NRC E-Filing rule (72 FR 49139, August 28, 2007). The E-Filing... the procedural requirements of E-Filing, at least ten (10) days prior to the filing deadline, the... the NRC in accordance with the E-Filing rule, the participant must file the document using the NRC's...

  14. Graphic displays on PCs of gaseous diffusion models of radionuclide releases to the atmosphere

    International Nuclear Information System (INIS)

    Campo Ortega, E. del

    1993-01-01

    The well-known MESOI program has been modified and improved to adapt it to a PC/AT with VGA colour monitor. Far from losing any of its powerful characteristics to calculate the transport, diffusion, deposition and decay of gaseous radioactive effluents discharged to the atmosphere, it has been enhanced to allow graphic viewing of concentrations, wind speed and direction and puff locations in colour, all on a background map of the site. The background covers a 75 x 75 km square and has a graphic grid density of 421 x 421 pixels. This means that effluent concentration is represented approximately every 170 metres in the 'clouded-area'. Among the modifications and enhancements made, the following are of particular interest: 1. A new subroutine called NUBE has been added, which calculates the distribution of effluent concentration of activity in a grid of 421 x 421 pixels. 2. Several subroutines have been added to obtain graphic displays and printouts of the cloud, wind field and puff locations. 3. Graphic display of the geographic plane of the area surrounding the effluent release point. 4. Off-line preparation of meteorological and topographical data files necessary for program execution. (author)

  15. Method and apparatus for rapid adjustment of process gas inventory in gaseous diffusion cascades

    International Nuclear Information System (INIS)

    Dyer, R.H.; Fowler, A.H.; Vanstrum, P.R.

    1977-01-01

    The invention relates to an improved method and system for making relatively large and rapid adjustments in the process gas inventory of an electrically powered gaseous diffusion cascade in order to accommodate scheduled changes in the electrical power available for cascade operation. In the preferred form of the invention, the cascade is readied for a decrease in electrical input by simultaneously withdrawing substreams of the cascade B stream into respective process-gas-freezing and storage zones while decreasing the datum-pressure inputs to the positioning systems for the cascade control valves in proportion to the weight of process gas so removed. Consequently, the control valve positions are substantially unchanged by the reduction in invention, and there is minimal disturbance of the cascade isotopic gradient. The cascade is readied for restoration of the power cut by simultaneously evaporating the solids in the freezing zones to regenerate the process gas substreams and introducing them to the cascade A stream while increasing the aforementioned datum pressure inputs in proportion to the weight of process gas so returned. In the preferred form of the system for accomplishing these operations, heat exchangers are provided for freezing, storing, and evaporating the various substreams. Preferably, the heat exchangers are connected to use existing cascade auxiliary systems as a heat sink. A common control is employed to adjust and coordinate the necessary process gas transfers and datum pressure adjustments

  16. Removal ratio of gaseous toluene and xylene transported from air to root zone via the stem by indoor plants.

    Science.gov (United States)

    Kim, K J; Kim, H J; Khalekuzzaman, M; Yoo, E H; Jung, H H; Jang, H S

    2016-04-01

    This work was designed to investigate the removal efficiency as well as the ratios of toluene and xylene transported from air to root zone via the stem and by direct diffusion from the air into the medium. Indoor plants (Schefflera actinophylla and Ficus benghalensis) were placed in a sealed test chamber. Shoot or root zone were sealed with a Teflon bag, and gaseous toluene and xylene were exposed. Removal efficiency of toluene and total xylene (m, p, o) was 13.3 and 7.0 μg·m(-3)·m(-2) leaf area over a 24-h period in S. actinophylla, and was 13.0 and 7.3 μg·m(-3)·m(-2) leaf area in F. benghalensis. Gaseous toluene and xylene in a chamber were absorbed through leaf and transported via the stem, and finally reached to root zone, and also transported by direct diffusion from the air into the medium. Toluene and xylene transported via the stem was decreased with time after exposure. Xylene transported via the stem was higher than that by direct diffusion from the air into the medium over a 24-h period. The ratios of toluene transported via the stem versus direct diffusion from the air into the medium were 46.3 and 53.7% in S. actinophylla, and 46.9 and 53.1% in F. benghalensis, for an average of 47 and 53% for both species. The ratios of m,p-xylene transported over 3 to 9 h via the stem versus direct diffusion from the air into the medium was 58.5 and 41.5% in S. actinophylla, and 60.7 and 39.3% in F. benghalensis, for an average of 60 and 40% for both species, whereas the ratios of o-xylene transported via the stem versus direct diffusion from the air into the medium were 61 and 39%. Both S. actinophylla and F. benghalensis removed toluene and xylene from the air. The ratios of toluene and xylene transported from air to root zone via the stem were 47 and 60 %, respectively. This result suggests that root zone is a significant contributor to gaseous toluene and xylene removal, and transported via the stem plays an important role in this process.

  17. Some engineering considerations when designing centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Edwards, T.T.

    1982-01-01

    A review is given of the three main areas where flexibility is needed in the design of centrifuge enrichment plants. These are: the need to cope with market requirements, the limitations imposed by currently available centrifuges and ever advancing centrifuge technology. Details of BNFL's experience with centrifuge enrichment at Capenhurst are presented. (U.K.)

  18. Genetic engineering of syringyl-enriched lignin in plants

    Science.gov (United States)

    Chiang, Vincent Lee; Li, Laigeng

    2004-11-02

    The present invention relates to a novel DNA sequence, which encodes a previously unidentified lignin biosynthetic pathway enzyme, sinapyl alcohol dehydrogenase (SAD) that regulates the biosynthesis of syringyl lignin in plants. Also provided are methods for incorporating this novel SAD gene sequence or substantially similar sequences into a plant genome for genetic engineering of syringyl-enriched lignin in plants.

  19. Centrifuge enrichment program

    International Nuclear Information System (INIS)

    Astley, E.R.

    1976-01-01

    Exxon Nuclear has been active in privately funded research and development of centrifuge enrichment technology since 1972. In October of 1975, Exxon Nuclear submitted a proposal to design, construct, and operate a 3000-MT SWU/yr centrifuge enrichment plant, under the provisions of the proposed Nuclear Fuel Assurance Act of 1975. The U.S. Energy Research and Development Administration (ERDA) accepted the proposal as a basis for negotiation. It was proposed to build a 1000-MT SWU/yr demonstration increment to be operational in 1982; and after successful operation for about one year, expand the facilities into a 3000-MT SWU/yr plant. As part of the overall centrifuge enrichment plant, a dedicated centrifuge manufacturing plant would be constructed; sized to support the full 3000-MT SWU/yr plant. The selection of the centrifuge process by Exxon Nuclear was based on an extremely thorough evaluation of current and projected enrichment technology; results show that the technology is mature and the process will be cost effective. The substantial savings in energy (about 93%) from utilization of the centrifuge option rather than gaseous diffusion is a compelling argument. As part of this program, Exxon Nuclear has a large hardware R and D program, plus a prototype centrifuge manufacturing capability in Malta, New York. To provide a full-scale machine and limited cascade test capability, Exxon Nuclear is constructing a $4,000,000 Centrifuge Test Facility in Richland, Washington. This facility was to initiate operations in the Fall of 1976. Exxon Nuclear is convinced that the centrifuge enrichment process is the rational selection for emergence of a commercial enrichment industry

  20. The assisting system for uranium enrichment plant operation

    International Nuclear Information System (INIS)

    Nakazawa, Hiroaki; Yamamoto, Fumio

    1990-01-01

    We have been developing an operation assisting system, partially supported by AI system, for uranium enrichment plant. The AI system is a proto-type system aiming a final one which can be applied to any future large uranium enrichment plant and also not only to specific operational area but also to complex and multi-phenomenon operational area. An existing AI system, for example facility diagnostic system that utilizes the result of CCT analysis as knowledge base, has weakness in flexibility and potentiality. To build AI system, we have developed the most suitable knowledge representations using deep knowledge for each facility or operation of uranium enrichment plant. This paper describes our AI proto-type system adopting several knowledge representations that can represent an uranium enrichment plant's operation with deep knowledge. (author)

  1. On-Line Enrichment Monitor for UF{sub 6} Gas Centrifuge Enrichment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Ianakiev, K. D.; Boyer, B.; Favalli, A.; Goda, J. M.; Hill, T.; Keller, C.; Lombardi, M.; Paffett, M.; MacArthur, D. W.; McCluskey, C.; Moss, C. E.; Parker, R.; Smith, M. K.; Swinhoe, M. T. [Los Alamos National Laboratory, Los Alamos (United States)

    2012-06-15

    This paper is a continuation of the Advanced Enrichment Monitoring Technology for UF{sub 6} Gas Centrifuge Enrichment Plant (GCEP) work, presented in the 2010 IAEA Safeguards Symposium. Here we will present the system architecture for a planned side-by-side field trial test of passive (186-keV line spectroscopy and pressure-based correction for UF{sub 6} gas density) and active (186-keV line spectroscopy and transmission measurement based correction for UF{sub 6} gas density) enrichment monitoring systems in URENCO's enrichment plant in Capenhurst. Because the pressure and transmission measurements of UF{sub 6} are complementary, additional information on the importance of the presence of light gases and the UF{sub 6} gas temperature can be obtained by cross-correlation between simultaneous measurements of transmission, pressure and 186-keV intensity. We will discuss the calibration issues and performance in the context of accurate, on-line enrichment measurement. It is hoped that a simple and accurate on-line enrichment monitor can be built using the UF{sub 6} gas pressure provided by the Operator, based on online mass spectrometer calibration, assuming a negligible (a small fraction of percent) contribution of wall deposits. Unaccounted-for wall deposits present at the initial calibration will lead to unwanted sensitivity to changes in theUF{sub 6} gas pressure and thus to error in the enrichment results. Because the accumulated deposits in the cascade header pipe have been identified as an issue for Go/No Go measurements with the Cascade Header Enrichment Monitor (CHEM) and Continuous Enrichment Monitor (CEMO), it is important to explore their effect. Therefore we present the expected uncertainty on enrichment measurements obtained by propagating the errors introduced by deposits, gas density, etc. and will discuss the options for a deposit correction during initial calibration of an On-Line Enrichment Monitor (OLEM).

  2. Simulation of gaseous emissions from electricity generating plant

    International Nuclear Information System (INIS)

    Bellhouse, G.M.; Whittington, H.W.

    1996-01-01

    In electricity supply networks, traditional dispatch algorithms are based on features such as economics and plant availability. Annual limits on emissions from fossil-fuelled stations are regarded as a restriction and set a ceiling on generation from particular stations. With the impending introduction of financial penalties on emissions, for example cal bon taxation, algorithms will have to be developed which allow the dispatch engineer to assess the cost in real-time of different generation options involving fossil-fuelled plants. Such an algorithm is described in this paper. (UK)

  3. Uranium enrichment decontamination and decommissioning fund

    International Nuclear Information System (INIS)

    1994-01-01

    One of the most challenging issues facing the Department of Energy's Office of Environmental Management is the cleanup of the three gaseous diffusion plants. In October 1992, Congress passed the Energy Policy Act of 1992 and established the Uranium Enrichment Decontamination and Decommissioning Fund to accomplish this task. This mission is being undertaken in an environmentally and financially responsible way by: devising cost-effective technical solutions; producing realistic life-cycle cost estimates, based on practical assumptions and thorough analysis; generating coherent long-term plans which are based on risk assessments, land use, and input from stakeholders; and, showing near-term progress in the cleanup of the gaseous diffusion facilities at Oak Ridge

  4. Determination of 1-octanol-air partition coefficient using gaseous diffusion in the air boundary layer.

    Science.gov (United States)

    Ha, Yeonjeong; Kwon, Jung-Hwan

    2010-04-15

    Exact determination of the partition coefficient between 1-octanol and air (K(OA)) is very important because it is a key descriptor for describing the thermodynamic partitioning between the air and organic phases. In spite of its importance, the number and quality of experimental K(OA) values for hydrophobic organic chemicals are limited because of experimental difficulties. Thus, to measure K(OA) values, a high-throughput method was developed that used liquid-phase extraction with 1-octanol drop at the tip of a microsyringe needle. The concentration in the headspace surrounding the 1 muL octanol drop was equilibrated with liquid octanol containing polycyclic aromatic hydrocarbons (PAHs). The change in concentrations of PAHs in the octanol drop was measured to obtain mass transfer rate constants, and these rate constants were then converted into K(OA) values using a film diffusion model. Thirteen polycyclic aromatic hydrocarbons with log K(OA) between 5 and 12 were chosen for the proof of the principle. Experimental determination of log K(OA) was accomplished in 30 h for PAHs with their log K(OA) less than 11. The measured log K(OA) values were very close to those obtained by various experimental and estimation methods in the literature, suggesting that this new method can provide a fast and easy determination of log K(OA) values for many chemicals of environmental interests. In addition, the applicability of the method can be extended to determine Henry's law constant for compounds with low vapor pressure and to estimate gaseous transfer rate of semivolatile compounds for environmental fate modeling.

  5. Uranium enrichment: investment options for the long term

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    The US government supplies a major portion of the enriched uranium used to fuel most of the nuclear power plants that furnish electricity in the free world. As manager of the US uranium enrichment concern, the Department of Energy (DOE) is investigating a number of technological choices to improve enrichment service and remain a significant world supplier. The Congress will ultimately select a strategy for federal investment in the uranium enrichment enterprise. A fundamental policy choice between possible future roles - that of the free world's main supplier of enrichment services, and that of a mainly domestic supplier - will underlie any investment decision the Congress makes. The technological choices are gaseous diffusion, gas centrifuge, and atomic vapor laser isotope separation (AVLIS). A base plan and four alternatives were examined by DOE and the Congressional Budget Office. In terms of total enterprise costs, Option IV, ultimately relying on advanced gas centrifuges for enrichment services, would offer the most economic approach, with costs over the full projection period totaling $123.5 billion. Option III, ultimately relying on AVLIS without gas centrifuge enrichment or gaseous diffusion, falls next in the sequence, with costs of $128.2 billion. Options I and II, involving combinations of the gas centrifuge and AVLIS technologies, follow closely with costs of $128.7 and $129.6 billion. The base plan has costs of $136.8 billion over the projection period. 1 figure, 22 tables

  6. Application of the HGSYSTEM/UF6 model to simulate atmospheric dispersion of UF6 releases from uranium enrichment plants

    International Nuclear Information System (INIS)

    Goode, W.D. Jr.; Bloom, S.G.; Keith, K.D. Jr.

    1995-01-01

    Uranium hexafluoride is a dense, reactive gas used in Gaseous Diffusion Plants (GDPs) to make uranium enriched in the 235 U isotope. Large quantities of UF 6 exist at the GDPs in the form of in-process gas and as a solid in storage cylinders; smaller amounts exist as hot liquid during transfer operations. If liquid UF 6 is released to the environment, it immediately flashes to a solid and a dense gas that reacts rapidly with water vapor in the air to form solid particles of uranyl fluoride and hydrogen fluoride gas. Preliminary analyses were done on various accidental release scenarios to determine which scenarios must be considered in the safety analyses for the GDPS. These scenarios included gas releases due to failure of process equipment and liquid/gas releases resulting from a breach of transfer piping from a cylinder. A major goal of the calculations was to estimate the response time for mitigating actions in order to limit potential off-site consequences of these postulated releases. The HGSYSTEM/UF 6 code was used to assess the consequences of these release scenarios. Inputs were developed from release calculations which included two-phase, choked flow followed by expansion to atmospheric pressure. Adjustments were made to account for variable release rates and multiple release points. Superpositioning of outputs and adjustments for exposure time were required to evaluate consequences based on health effects due to exposures to uranium and HF at a specific location

  7. Metal enriched gaseous halos around distant radio galaxies: Clues to feedback in galaxy formation

    Energy Technology Data Exchange (ETDEWEB)

    Reuland, M; van Breugel, W; de Vries, W; Dopita, A; Dey, A; Miley, G; Rottgering, H; Venemans, B; Stanford, S A; Lacy, M; Spinrad, H; Dawson, S; Stern, D; Bunker, A

    2006-08-01

    We present the results of an optical and near-IR spectroscopic study of giant nebular emission line halos associated with three z > 3 radio galaxies, 4C 41.17, 4C 60.07 and B2 0902+34. Previous deep narrow band Ly{alpha} imaging had revealed complex morphologies with sizes up to 100 kpc, possibly connected to outflows and AGN feedback from the central regions. The outer regions of these halos show quiet kinematics with typical velocity dispersions of a few hundred km s{sup -1}, and velocity shears that can mostly be interpreted as being due to rotation. The inner regions show shocked cocoons of gas closely associated with the radio lobes. These display disturbed kinematics and have expansion velocities and/or velocity dispersions >1000 km s{sup -1}. The core region is chemically evolved, and we also find spectroscopic evidence for the ejection of enriched material in 4C 41.17 up to a distance of {approx} 60 kpc along the radio-axis. The dynamical structures traced in the Ly{alpha} line are, in most cases, closely echoed in the Carbon and Oxygen lines. This shows that the Ly{alpha} line is produced in a highly clumped medium of small filling factor, and can therefore be used as a tracer of the dynamics of HzRGs. We conclude that these HzRGs are undergoing a final jet-induced phase of star formation with ejection of most of their interstellar medium before becoming 'red and dead' Elliptical galaxies.

  8. The outline of clearance plan for Rokkasho uranium enrichment plant

    International Nuclear Information System (INIS)

    Kojima, Takuo; Sasaki, Hitoshi; Shouno, Shuuzou; Nozawa, Kenji

    2011-01-01

    Japan Nuclear Fuel Limited (JNFL) started operation of uranium enrichment by metal cylinder centrifuge at Rokkasho Uranium Enrichment Plant in 1992. Since operation start, JNFL has extended the plant capacity sequentially, but metal cylinder centrifuges ceased operation gradually with time. Replacement to advanced centrifuge is under construction now. Generally, Uranium Enrichment Plant continues operation by replacing centrifuges after a certain period of operation. So, many used centrifuges (metal waste) are generated through the operation period. JNFL is now considering the disposal plan. We can reduce the radioactivity level that is not necessary to treat as the radioactive waste by decontaminating the radioactive material sticking to the surface of metal materials of used centrifuge. And JNFL plants to recycle (reuse) metal material by making much of the clearance system. (author)

  9. Monitoring the enrichment of the UF6 in the pipework of a gas centrifuge enrichment plant

    International Nuclear Information System (INIS)

    Packer, T.W.; Close, D.A.; Pratt, J.C.

    1987-01-01

    Research in the UK and the US has resulted in the development of a nondestructive assay instrument which can confirm the presence of low enriched uranium, on a rapid Go, No-Go basis, in cascade header pipework in the centrifuge enrichment plant at Capenhurst. The instrument is based on gamma-ray spectrometry and x-ray fluorescence analysis. It allows pipes, 120mm outer diameter, to be inspected in a total measurement time of approximately 30 minutes. This paper describes the techniques developed and includes the results obtained during a demonstration to, and preliminary in-plant measurements by, members of the IAEA and EURATOM Inspectorates at Capenhurst

  10. Evaluation of the uranium enrichment demonstration plant project

    International Nuclear Information System (INIS)

    Sugitsue, Noritake

    2001-01-01

    In this report, the organization system of the uranium enrichment business is evaluated, based on the operation of the uranium enrichment demonstration plant. As a result, in uranium enrichment technology development or business, it was acknowledged that maintenance of the organization which has the Trinity of a research/engineering/operation was necessary in an industrialization stage by exceptional R and D cycle. Japan Nuclear Fuel Ltd. (JNFL) set up the Rokkashomura Aomori Uranium Enrichment Research and Development Center in November 2000. As a result, the system that company directly engaged in engineering development was prepared. And results obtained in this place is expected toward certain establishment of the uranium enrichment business of Japan. (author)

  11. Improved verification methods for safeguards verifications at enrichment plants

    International Nuclear Information System (INIS)

    Lebrun, A.; Kane, S. C.; Bourva, L.; Poirier, S.; Loghin, N. E.; Langlands, D.

    2009-01-01

    The International Atomic Energy Agency (IAEA) has initiated a coordinated research and development programme to improve its verification methods and equipment applicable to enrichment plants. The programme entails several individual projects to meet the objectives of the IAEA Safeguards Model Approach for Gas Centrifuge Enrichment Plants updated in 2006. Upgrades of verification methods to confirm the absence of HEU (highly enriched uranium) production have been initiated and, in particular, the Cascade Header Enrichment Monitor (CHEM) has been redesigned to reduce its weight and incorporate an electrically cooled germanium detector. Such detectors are also introduced to improve the attended verification of UF 6 cylinders for the verification of the material balance. Data sharing of authenticated operator weighing systems such as accountancy scales and process load cells is also investigated as a cost efficient and an effective safeguards measure combined with unannounced inspections, surveillance and non-destructive assay (NDA) measurement. (authors)

  12. Improved verification methods for safeguards verifications at enrichment plants

    Energy Technology Data Exchange (ETDEWEB)

    Lebrun, A.; Kane, S. C.; Bourva, L.; Poirier, S.; Loghin, N. E.; Langlands, D. [Department of Safeguards, International Atomic Energy Agency, Wagramer Strasse 5, A1400 Vienna (Austria)

    2009-07-01

    The International Atomic Energy Agency (IAEA) has initiated a coordinated research and development programme to improve its verification methods and equipment applicable to enrichment plants. The programme entails several individual projects to meet the objectives of the IAEA Safeguards Model Approach for Gas Centrifuge Enrichment Plants updated in 2006. Upgrades of verification methods to confirm the absence of HEU (highly enriched uranium) production have been initiated and, in particular, the Cascade Header Enrichment Monitor (CHEM) has been redesigned to reduce its weight and incorporate an electrically cooled germanium detector. Such detectors are also introduced to improve the attended verification of UF{sub 6} cylinders for the verification of the material balance. Data sharing of authenticated operator weighing systems such as accountancy scales and process load cells is also investigated as a cost efficient and an effective safeguards measure combined with unannounced inspections, surveillance and non-destructive assay (NDA) measurement. (authors)

  13. Profile of World Uranium Enrichment Programs - 2007

    International Nuclear Information System (INIS)

    Laughter, Mark D.

    2007-01-01

    It is generally agreed that the most difficult step in building a nuclear weapon is acquiring weapons grade fissile material, either plutonium or highly enriched uranium (HEU). Plutonium is produced in a nuclear reactor, while HEU is produced using a uranium enrichment process. Enrichment is also an important step in the civil nuclear fuel cycle, in producing low enriched uranium (LEU) for use in fuel for nuclear reactors. However, the same equipment used to produce LEU for nuclear fuel can also be used to produce HEU for weapons. Safeguards at an enrichment plant are the array of assurances and verification techniques that ensure uranium is only enriched to LEU, no undeclared LEU is produced, and no uranium is enriched to HEU or secretly diverted. There are several techniques for enriching uranium. The two most prevalent are gaseous diffusion, which uses older technology and requires a lot of energy, and gas centrifuge separation, which uses more advanced technology and is more energy efficient. Gaseous diffusion plants (GDPs) provide about 40% of current world enrichment capacity, but are being phased out as newer gas centrifuge enrichment plants (GCEPs) are constructed. Estimates of current and future enrichment capacity are always approximate, due to the constant upgrades, expansions, and shutdowns occurring at enrichment plants, largely determined by economic interests. Currently, the world enrichment capacity is approximately 53 million kg-separative work units (SWU) per year, with 22 million in gaseous diffusion and 31 million in gas centrifuge plants. Another 23 million SWU/year of capacity are under construction or planned for the near future, almost entirely using gas centrifuge separation. Other less-efficient techniques have also been used in the past, including electromagnetic and aerodynamic separations, but these are considered obsolete, at least from a commercial perspective. Laser isotope separation shows promise as a possible enrichment technique

  14. Experience with environmental sampling at gas centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Ekenstam, G. af; Bush, W.; Janov, J.; Kuhn, E.; Ryjinski, M.

    2001-01-01

    Environmental sampling has been used routinely by the IAEA since 1996 after the IAEA Board of Governors approved it in March 1995 as a new technique to strengthen safeguards and improve efficiency. In enrichment plants it is used to confirm that there has been no production of highly enriched uranium (HEU), or production of uranium at above the declared enrichment. The use of environmental sampling is based on the assumption that every process, no matter how leak tight, will release small amounts of process material to the environment. Even though these releases of nuclear material are extremely small in gas centrifuge enrichment plants, and well below levels of concern from a health physics and safety standpoint, they are detectable and their analysis provides an indication of the enrichment of the material that has been processed in the plant. The environmental samples at enrichment plants are collected by swiping selected areas of the plant with squares of cotton cloth (10x10 cm) from sampling kits prepared in ultra clean condition. The squares of cotton cloth sealed in plastic bags are sent for analysis to the Network Analytical Laboratories. The analysis includes the measurement of the uranium isotopic composition in uranium-containing particles by Thermal lonization Mass Spectroscopy (TIMS) or Secondary ION Mass Spectroscopy (SIMS). Since the implementation of environmental sampling, swipes have been collected from 240 sampling points at three gas centrifuge plants of URENCO, which have a total throughput of more than 8,000 tonnes of uranium per year. The particle analysis results generally reflected the known operational history of the plants and confirmed that they had only been operated to produce uranium with enrichment less than 5% 235 U. The information about the content of the minor isotopes 234 U and 236 U also indicates that depleted and recycled uranium were sometimes used as feed materials in some plants. An example is given of the TIMS particle

  15. Uranium enrichment techniques

    International Nuclear Information System (INIS)

    Hamdoun, N.A.

    2007-01-01

    This article includes an introduction about the isotopes of natural uranium, their existence and the difficulty of the separation between them. Then it goes to the details of a number of methods used to enrich uranium: Gaseous Diffusion method, Electromagnetic method, Jet method, Centrifugal method, Chemical method, Laser method and Plasma method.

  16. Uranium enrichment activities: the SILVA program

    International Nuclear Information System (INIS)

    Guyot, J.; Cazalet, J.; Camarcat, N.; Figuet, J.

    1994-01-01

    Through its commitment to a nuclear electricity generation policy, France holds today a specific position in the uranium enrichment market thanks to the modern multinational EURODIF gaseous diffusion plant. France has, altogether, a long-term goal in developing SILVA, a laser uranium enrichment process, based on the selective photo-ionization of U-235. After reviewing the fundamentals of SILVA (the laser system with copper vapor lasers and dye lasers and the separator system), a description of the general organization of the R and D program is provided going through basic research, subsystems assessment, production demonstrations and simulations (with the LACAN code), plant design and economics. The general schedule of SILVA is outlined, leading to the possible construction of a commercial plant. 7 figs., 11 refs

  17. Effect of Oxygen Enrichment in Propane Laminar Diffusion Flames under Microgravity and Earth Gravity Conditions

    Science.gov (United States)

    Bhatia, Pramod; Singh, Ravinder

    2017-06-01

    Diffusion flames are the most common type of flame which we see in our daily life such as candle flame and match-stick flame. Also, they are the most used flames in practical combustion system such as industrial burner (coal fired, gas fired or oil fired), diesel engines, gas turbines, and solid fuel rockets. In the present study, steady-state global chemistry calculations for 24 different flames were performed using an axisymmetric computational fluid dynamics code (UNICORN). Computation involved simulations of inverse and normal diffusion flames of propane in earth and microgravity condition with varying oxidizer compositions (21, 30, 50, 100 % O2, by mole, in N2). 2 cases were compared with the experimental result for validating the computational model. These flames were stabilized on a 5.5 mm diameter burner with 10 mm of burner length. The effect of oxygen enrichment and variation in gravity (earth gravity and microgravity) on shape and size of diffusion flames, flame temperature, flame velocity have been studied from the computational result obtained. Oxygen enrichment resulted in significant increase in flame temperature for both types of diffusion flames. Also, oxygen enrichment and gravity variation have significant effect on the flame configuration of normal diffusion flames in comparison with inverse diffusion flames. Microgravity normal diffusion flames are spherical in shape and much wider in comparison to earth gravity normal diffusion flames. In inverse diffusion flames, microgravity flames were wider than earth gravity flames. However, microgravity inverse flames were not spherical in shape.

  18. Results from uranium deposition studies for development of a Limited Frequency-Unannounced Access (LFUA) inspection strategy for gas centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Cooley, J.N.; Fields, L.W.; Swindle, D.W.

    1985-06-01

    Uranium deposition studies were performed on a test loop system designed to simulate process gas flow through the header piping of a gas centrifuge enrichment plant. The objectives of these studies were to investigate the effectiveness of an in-line gaseous cleaning agent in removing uranium in pipe deposits and to analyze long-term deposition growth and isotopic exchange under simulated centrifuge plant operating conditions. The test loop studies are described, the results are reported, and the implications for analyzing actual plant data are discussed. Results indicate that: 93% of the uranium deposit is removed within 15 min when a pipe is pressurized with gaseous ClF 3 ; the isotopic abundance of a highly enriched uranium deposit remains unchanged when UF 6 of a lower assay is introduced into the pipe; and air inleakage will be the cause of the largest deposits in centrifuge plant process header pipes. 3 refs., 3 figs., 3 tabs

  19. Status report on uranium enrichment associates

    International Nuclear Information System (INIS)

    Langley, R.A. Jr.; O'Donnell, A.J.; Garrett, G.A.

    1977-01-01

    Uranium Enrichment Associates (UEA) had as its priority project financing, an approach in which the total project is financially self-liquidating. UEA worked with financial institutions to define the combination of assurances and guarantees required by lenders in order to provide the required debt funding. UEA's assets against which the debt liability for the plant would be balanced would be the facilities under construction and the equipment on order. On the customer side, there was major concern on the part of the utilities of whether private industry would be able to complete and operate the plant owing to many of the same possibilities which concerned financial institutions. The disparity between the conditions under which financing could be obtained and the terms acceptable to utilities was a significant element in EUA's choice of process to use for its enrichment plants. UEA's technical staff then began to parallel conceptual designs of gaseous diffusion and gas cenrifuge plants. UEA negotiated with ERDA on the terms of a Cooperative Arrangement, within the provisions of the NFAA, providing the minimum conditions necessary to obtain financing and contracts with utilities for enrichment sources. The UEA plant has several features different from the ERDA plants. The UEA plant used only two basic stage sizes. The UEA design employed four main process buildings. The partners in UEA have mutually agreed to follow the private uranium enrichment project to a logical conclusion. 6 figures

  20. Enrichment of pasta with different plant proteins.

    Science.gov (United States)

    Kaur, Gurpreet; Sharma, Savita; Nagi, H P S; Ranote, P S

    2013-10-01

    Effects of supplementation of plant proteins from mushroom powder, Bengal gram flour and defatted soy flour at different levels were assessed on the nutritional quality of pasta. Supplementation of wheat semolina was done with mushroom powder (0-12%), Bengal gram flour (0-20%) and defatted soy flour (0-15%). Mushroom powder and defatted soy flour increased the cooking time of pasta whereas non significant variation was observed in cooking time of Bengal gram supplemented pasta. Significant correlation (r = 0.97, p ≤ 0.05) was observed between water absorption and volume expansion of pasta. Instantization of pasta by steaming improved the cooking quality. Steamed pasta absorbed less water and leached fewer solids during cooking. On the basis of cooking and sensory quality, pasta in combination with 8% mushroom powder, 15% Bengal gram flour and 9% defatted soy flour resulted in a better quality and nutritious pasta.

  1. Centrifuge enrichment plants. (Latest citations from the NTIS bibliographic database). Published Search

    International Nuclear Information System (INIS)

    1993-09-01

    The bibliography contains citations concerning the design, control, monitoring, and safety of centrifuge enrichment plants. Power supplies, enrichment plant safeguards, facility design, cascade heater test loops to monitor the enrichment process, inspection strategies, and the socioeconomic effects of centrifuge enrichment plants are examined. Radioactive waste disposal problems are considered. (Contains a minimum of 171 citations and includes a subject term index and title list.)

  2. Industrial plants for production of highly enriched nitrogen-15

    International Nuclear Information System (INIS)

    Krell, E.; Jonas, C.

    1977-01-01

    A discussion is presented of the present stage of development of large-scale enrichment of 15 N. The most important processes utilized to separate nitrogen isotopes, namely chemical exchange in the NO/NO 2 /HNO 3 system and low-temperature distillation of NO at -151 0 C, are compared, especially with respect to their economics and use of energy. As examples, chemical exchange plants in the GDR are discussed, and the research activities necessary to optimize the process, especially to solve aerodynamic, hydrodynamic, interface and processing problems, are reviewed. Good results were obtained by the choice of an optimum location and the design of a plant for pre-enrichment to 10 at.% 15 N and an automatically operating two-section cascade for the high enrichment of 15 N to more than 99 at.%. The chemical industry has taken over operation of the plant with the consequence that the raw materials are all available without additional transport. All by-products (nitrous gases and sulphuric acid) are returned for use elsewhere within the industry. The technology of the plant has been chosen so that the quantity of highly enriched product can be varied within a wide range. The final product is used to synthesize more than 250 different 15 N-labelled compounds which are also produced on an industrial scale. (author)

  3. Study of cerium diffusion in undoped lithium-6 enriched glass with Rutherford backscattering spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiaodong, E-mail: xzhang39@utk.edu [Department of Nuclear Engineering, University of Tennessee, TN 37996 (United States); Moore, Michael E.; Lee, Kyung-Min; Lukosi, Eric D. [Department of Nuclear Engineering, University of Tennessee, TN 37996 (United States); Hayward, Jason P. [Department of Nuclear Engineering, University of Tennessee, TN 37996 (United States); Oak Ridge National Lab, Oak Ridge, TN 37831 (United States)

    2016-07-01

    Undoped lithium-6 enriched glasses coated with pure cerium (99.9%) with a gold protection layer on top were heated at three different temperatures (500, 550, and 600 °C) for varied durations (1, 2, and 4 h). Diffusion profiles of cerium in such glasses were obtained with the conventional Rutherford backscattering technique. Through fitting the diffusion profiles with the thin-film solution of Fick’s second law, diffusion coefficients of cerium with different annealing temperatures and durations were solved. Then, the activation energy of cerium for the diffusion process in the studied glasses was found to be 114 kJ/mol with the Arrhenius equation.

  4. Study of cerium diffusion in undoped lithium-6 enriched glass with Rutherford backscattering spectrometry

    Science.gov (United States)

    Zhang, Xiaodong; Moore, Michael E.; Lee, Kyung-Min; Lukosi, Eric D.; Hayward, Jason P.

    2016-07-01

    Undoped lithium-6 enriched glasses coated with pure cerium (99.9%) with a gold protection layer on top were heated at three different temperatures (500, 550, and 600 °C) for varied durations (1, 2, and 4 h). Diffusion profiles of cerium in such glasses were obtained with the conventional Rutherford backscattering technique. Through fitting the diffusion profiles with the thin-film solution of Fick's second law, diffusion coefficients of cerium with different annealing temperatures and durations were solved. Then, the activation energy of cerium for the diffusion process in the studied glasses was found to be 114 kJ/mol with the Arrhenius equation.

  5. Diffuse-Illumination Systems for Growing Plants

    Science.gov (United States)

    May, George; Ryan, Robert

    2010-01-01

    Agriculture in both terrestrial and space-controlled environments relies heavily on artificial illumination for efficient photosynthesis. Plant-growth illumination systems require high photon flux in the spectral range corresponding with plant photosynthetic active radiation (PAR) (400 700 nm), high spatial uniformity to promote uniform growth, and high energy efficiency to minimize electricity usage. The proposed plant-growth system takes advantage of the highly diffuse reflective surfaces on the interior of a sphere, hemisphere, or other nearly enclosed structure that is coated with highly reflective materials. This type of surface and structure uniformly mixes discrete light sources to produce highly uniform illumination. Multiple reflections from within the domelike structures are exploited to obtain diffuse illumination, which promotes the efficient reuse of photons that have not yet been absorbed by plants. The highly reflective surfaces encourage only the plant tissue (placed inside the sphere or enclosure) to absorb the light. Discrete light sources, such as light emitting diodes (LEDs), are typically used because of their high efficiency, wavelength selection, and electronically dimmable properties. The light sources are arranged to minimize shadowing and to improve uniformity. Different wavelengths of LEDs (typically blue, green, and red) are used for photosynthesis. Wavelengths outside the PAR range can be added for plant diagnostics or for growth regulation

  6. The uranium enrichment market and long-term technological options

    International Nuclear Information System (INIS)

    Schneider-Maunoury, A.

    1992-01-01

    The world enrichment market situation is clearly delineated up to the year 2000. Including the East European countries, worldwide enriched uranium requirements should reach 40 million separative work units (SWUs) a year and production capacity should reach 44 millions SWUs. Two-thirds of this capacity will be supplied by the gaseous diffusion process and one-third by the centrifuge process. The enrichment processes currently considered are: (i) the gaseous diffusion process, (ii) the centrifuge process, (iii) the chemical treatment process and (iv) the laser processes, long-term assessment of the enrichment market up to the year 2015. Two scenarios may be envisioned for the (i) Public opinion will continue to block the development of nuclear power, and requirements will level off at 40 million SWUs. (ii) Changing attitudes will favor a reasonable approach enabling a revival of nuclear power expansion around 1995. Requirements should then increase starting in 2005 and would readily attain 60 million SWUs a year by 2015. Depending on market conditions, enrichment process options will be influenced either entirely by cost considerations, without allowance for the time factor, or by need to meet demand. Demonstrations of the industrial validity of laser processes are expected by 1992 - 1995 and, if interest in nuclear power makes a comeback, decisions should be made between 1995 and 2000 to build new large-capacity enrichment plants. The gaseous diffusion process may still be used for a long time if nuclear power is judiciously employed. The centrifuge process will be fully mature by the year 2000. The uranium vapor laser processes offer the most promise and should ultimately prevail. the chemical processes, though outsiders, deserve watching. (author)

  7. Diffusion coefficients of D2 and HT in the medium of gaseous protium and in crystals of NaX zeolite

    International Nuclear Information System (INIS)

    Polevoj, A.S.

    1993-01-01

    Coefficients of HT diffusion (absent in literature) in gaseous protium medium and in crystals of the NaX zeolite compared with similar values of these coefficients for deuterium are determined on the basis of analysis of experimental data on effect NaX zeolite grain size and of H 2 -HT gaseous mixture consumption in the sorption column at separation of hydrogen atoms on the value of transfer unit. 15 refs., 1 fig., 1 tab

  8. Gaseous environment of plants and activity of enzymes of carbohydrate catabolism

    International Nuclear Information System (INIS)

    Ivanov, B.F.; Zemlyanukhin, A.A.; Igamberdiev, A.U.; Salam, A.M.M.

    1989-01-01

    The authors investigated the action of hypoxia and high CO 2 concentration in the atmosphere on activity of phosphofructokinase, aldolase, glucose phosphate isomerase, glucose-6-phosphate dehydrogenase, lactate dehydrogenase, alcohol dehydrogenase, and isocitrate lyase in pea seedlings (Pisum sativum L.), corn scutella (Zea mays L.), and hemp cotyledons (Cannabis sativa L.). The first 4-12h of hypoxia witnessed suppression of enzymes of the initial stages of glycolysis (glucose-6-phosphate isomerase, phosphofructokinase)and activation of enzymes of its final stages (alcohol dehydrogenase and lactate dehydrogenase) and enzymes linking glycolysis and the pentose phosphate pathway (aldolase and glucose-6-phosphate dehydrogenase). An excess of CO 2 in the environment accelerated and amplified this effect. At the end of a 24-h period of anaerobic incubation, deviations of enzyme activity from the control were leveled in both gaseous environments. An exception was observed in the case of phosphofructokinase, whose activity increased markedly at this time in plants exposed to CO 2 . Changes in activity of the enzymes were coupled with changes in their kinetic parameters (apparent K m and V max values). The activity of isocitrate lyase was suppressed in both variants of hypoxic gaseous environments, a finding that does not agree with the hypothesis as to participation of the glyoxylate cycle in the metabolic response of plants to oxygen stress. Thus, temporary inhibition of the system of glycolysis and activation of the pentose phosphate pathway constituted the initial response of the plants to O 2 stress, and CO 2 intensified this metabolic response

  9. Determination of the separation factor of uranium isotopes by gaseous diffusion; Determination des facteurs de separation des isotopes de l'uranium par diffusion gazeuse

    Energy Technology Data Exchange (ETDEWEB)

    Bilous, O; Counas, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    A 12-stage pilot separation cascade with a low output has been constructed to measure the separation factor of uranium isotopes by gaseous diffusion. The report describes some of the separation results obtained, and also provides information on the time necessary for equilibrium to be established and on the influence of various perturbations on the pressure profile in the cascade. (author) [French] Une cascade pilote de 12 etages de separation a faible debit a ete construite pour mesurer le facteur de separation des isotopes de l'uranium par diffusion gazeuse. Le rapport decrit certains des resultats de separation obtenus et fournit egalement des donnees sur les temps de mise en equilibre et l'influence de diverses perturbations sur le profil des pressions dans la cascade. (auteur)

  10. Nondestructive determination of uranium-235 enrichment in gas ultracentrifugation enrichment plants

    International Nuclear Information System (INIS)

    Lauppe, W.D.; Richter, B.; Stein, G.

    1990-02-01

    Based on similar studies in the USA and the UK, two γ spectroscopic techniques were propagated by the IAEA, after they had been sucesssfully tried at Capenhurst (GB) centrifuge plant. It was assumed by the IAEA that these methods would be transferable to the Almelo and Gronau plants, even without knowledge of the specific plant parameters there. The scope of this research project covered the study and further development of the proposed γ-spectroscopic measuring methods for applicability in the GUC plant in Gronau. The research came within the terms of reference of Task C.14.7 of the IAEA and BMFT (German Federal Ministry of Research and Technology)'s joint research and development programme. When the funded project first started, the Gronau plant was not yet on stream. The initial measurements were therefore, taken in Almelo, where conditions were similar to those in Gronau. The report describes the underlying problems which occur in relation to the non-destructive measuring of 235 U enrichment under the specific boundary conditions in Almelo and Gronau. The results illustrate the limitations of application of the measuring techniques, even after adjustment to actual conditions in Almelo and Gronau. It is not always possible to obtain a reliable yes/no answer in favour of slightly enriched uranium, particularly in product lines with extreme boundary conditions, irrespective of the technique applied. (orig.) [de

  11. UF6 Density and Mass Flow Measurements for Enrichment Plants using Acoustic Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Good, Morris S.; Smith, Leon E.; Warren, Glen A.; Jones, Anthony M.; Ramuhalli, Pradeep; Roy, Surajit; Moran, Traci L.; Denslow, Kayte M.; Longoni, Gianluca

    2017-09-01

    A key enabling capability for enrichment plant safeguards being considered by the International Atomic Energy Agency (IAEA) is high-accuracy, noninvasive, unattended measurement of UF6 gas density and mass flow rate. Acoustic techniques are currently used to noninvasively monitor gas flow in industrial applications; however, the operating pressures at gaseous centrifuge enrichment plants (GCEPs) are roughly two orders magnitude below the capabilities of commercial instrumentation. Pacific Northwest National Laboratory is refining acoustic techniques for estimating density and mass flow rate of UF6 gas in scenarios typical of GCEPs, with the goal of achieving 1% measurement accuracy. Proof-of-concept laboratory measurements using a surrogate gas for UF6 have demonstrated signatures sensitive to gas density at low operating pressures such as 10–50 Torr, which were observed over the background acoustic interference. Current efforts involve developing a test bed for conducting acoustic measurements on flowing SF6 gas at representative flow rates and pressures to ascertain the viability of conducting gas flow measurements under these conditions. Density and flow measurements will be conducted to support the evaluation. If successful, the approach could enable an unattended, noninvasive approach to measure mass flow in unit header pipes of GCEPs.

  12. CENTAR gas centrifuge enrichment project: economics and engineering considerations

    International Nuclear Information System (INIS)

    Fishman, A.M.

    1977-01-01

    Description of some economic and engineering considerations of the CENTAR Associates' 3000000 SWU/yr gas centrifuge uranium enrichment plant project. The need for uranium enrichment facilities is discussed, and the advantages of using the centrifuge process rather than the presently used gaseous diffusion process are reviewed. A description of the CENTAR plant is given, highlighting the major features of the facility. Since the centiruges to be used in the plant account for approximately 50% of the capital cost of the project, the philosophy of their manufacture and procurement is discussed. Various design considerations which bear upon process economics are presented to give the reader an appreciation of the subtleties of the technology and the flexibility possible in plant design. Special attention is given to meeting the needs of the utility customer at the lowest possible cost

  13. Developments on uranium enrichment processes in France

    International Nuclear Information System (INIS)

    Frejacques, C.; Gelee, M.; Massignon, D.; Plurien, P.

    1977-01-01

    Gaseous diffusion has so far been the main source of supply for enriched uranium and it is only recently that the gas centrifuge came into the picture. Numerous other isotope separation processes have been considered or are being assessed, and there is nothing to exclude the future use of a new process. Developments on likely new processes have been carried out by many organizations both governmental and private. The French Commissariat a l'energie atomique, besides their very extensive endeavours already devoted to gaseous diffusion, have studied and developed the gas centrifuge, chemical exchange, aerodynamic and selective photoexcitation processes. The gaseous diffusion process, selected by Eurodif for the Tricastin plant, and which will also be used by Coredif, is discussed in another paper in these Proceedings. This process is the technico-economic yardstick on which our comparisons are based. Within the limits of their development level, processes are compared on the basis of the separative work cost components: specific investment, specific power consumption and power cost, and specific operating and maintenance costs. (author)

  14. A new era in U.S. uranium enrichment

    International Nuclear Information System (INIS)

    Longenecker, J.R.

    1984-01-01

    Complex market conditions, including lower than anticipated electrical growth rates, creation of a large spot market of enriched uranium, fluctuations in currency exchange rates, and certain political considerations, have created an unstable market for all primary producers, including the United States. In response to these conditions, the Department of Energy made significant changes to the U.S. program including the issuance of the Utility Services contract on January 18, 1984. Other major changes include redirecting research and development efforts on the advanced gas centrifuge and atomic vapor laser isotope separation processes, rescoping of the Gas Centrifuge Enrichment Plant project, and reevaluation of the operational mode of the three gaseous diffusion plants. Taken together, we believe these actions will retain the U.S. position of leadership in uranium enrichment. In summary, we plan to compete--through introduction of the world's most advanced, lowest cost technology and through responsiveness to our customers' needs

  15. Adaptive control theory of concentration in the uranium enrichment plant

    International Nuclear Information System (INIS)

    Sugitsue, Noritake; Miyagawa, Hiroshi; Yokoyama, Kaoru; Nakakura, Hiroyuki

    1999-01-01

    This paper presents the new adaptive control of concentration in the uranium enrichment plant. The purpose of this control system is average concentration control in production tram. As a result the accuracy and practical use of this control system have already been confirmed by the operation of the uranium enrichment demonstration plant. Three elements of technology are required to this method. The first is the measurement of the concentration using product flow quantity change. This technology shall be called 'Qp difference to Xp transform method'. The second is the relationship between temperature change and flow quantity using G.M.D.H. (Groupe Method of Data Handling) and the third is the estimation of temperature change using AR (Auto-regressive) model. (author)

  16. Process of advective diffusive enrichment using differential gradients and the effects of variations in relaxation times

    International Nuclear Information System (INIS)

    Suarez Antola R.; Bernasconi, G.; Bertolotti, Angel

    1995-01-01

    A multicomponent solution is considered in advective diffusion chambers between two half-permeable barriers. A mathematical model is developed to calculate the concentration fields in the chamber. A new enrichment process is proposed and assessed using a digital simulation of space-time dynamics, based on the analytical solution of the model

  17. Continuous monitoring of variations in the 235U enrichment of uranium in the header pipework of a centrifuge enrichment plant

    International Nuclear Information System (INIS)

    Packer, T.W.

    1991-01-01

    Non-destructive assay equipment, based on gamma-ray spectrometry and x-ray fluorescence analysis has previously been developed for confirming the presence of low enriched uranium in the header pipework of UF 6 gas centrifuge enrichment plants. However inspections can only be carried out occasionally on a limited number of pipes. With the development of centrifuge enrichment technology it has been suggested that more frequent, or ideally, continuous measurements should be made in order to improve safeguards assurance between inspections. For this purpose we have developed non-destructive assay equipment based on continuous gamma-ray spectrometry and x-ray transmission measurements. This equipment is suitable for detecting significant changes in the 235 U enrichment of uranium in the header pipework of new centrifuge enrichment plants. Results are given in this paper of continuous measurements made in the laboratory and also on header pipework of a centrifuge enrichment plant at Capenhurst

  18. Georges Besse 2. A new era for enrichment

    International Nuclear Information System (INIS)

    2009-01-01

    Since 1978, AREVA group subsidiary EURODIF's Georges Besse plant has been using gaseous diffusion to enrich uranium and meet the requirements of electricity utilities. Georges Besse II plant, which will use far less electricity, will replace George Besse not so long. The Georges Besse II plant is located on the Tricastin nuclear site in southern France. AREVA ensure delivery of uranium enrichment services in accordance with customer expectations. AREVA obtained the right to use URENCO's centrifugation technology on July 3, 2006. This is the process to be used at Georges Besse II. The new uranium enrichment plant will comprise two enrichment units, with a total production capacity of 7.5 million separative work units, which can be extended to 11 million if needed. Each enrichment unit will include: a Centrifuge Assembly Building (CAB), a Centrifuge Utility Building (CUB) with offices and control room, annexes for purification, supply and extraction of uranium hexafluoride (UF 6 ), modules containing the halls that house the centrifuge cascades. The modular design of the Georges Besse II plant will allow production in the first cascade where as the others cascades are build. The first cascade should be operational in the first half of 2009. At an overall cost of 3 billion euros, this project is one of the largest investments of the decade in France On November 24, 2003, AREVA and URENCO signed an agreement under which AREVA would buy 50% of the shares in the Enrichment Technology Company (ETC), which designs and manufactures centrifuges

  19. Novel gaseous ethylene binding inhibitor prevents ethylene effects in potted flowering plants

    Energy Technology Data Exchange (ETDEWEB)

    Serek, M.; Reid, M.S. (Univ. of California, Davis, CA (United States). Dept. of Environmental Horticulture); Sisler, E.C. (North Carolina State Univ., Raleigh, NC (United States). Dept. of Biochemistry)

    1994-11-01

    A 6-hour fumigation of flowering Begonia xelatior hybrida Fotsch. Najada' and Rosa', B. xtuberhybrida Voss. Non-Stop', Kalanchoe blossfeldiana Poelln. Tropicana', and Rosa hybrida L. Victory Parade' plants with 1-MCP, (formerly designated as SIS-X), a gaseous nonreversible ethylene binding inhibitor, strongly inhibited exogenous ethylene effects such as bud and flower drop, leaf abscission, and accelerated flower senescence. The inhibitory effects of 1-MCP increased linearly with concentration, and at 20 nl-liter[sup [minus]1] this compound gave equal protection to that afforded by spraying the plants with a 0.5 STS mM solution. Chemical names used: 1-methylcyclopropene (1-MCP), silver thiosulfate (STS).

  20. Quality of deli-style turkey enriched with plant sterols.

    Science.gov (United States)

    Grasso, S; Brunton, N P; Lyng, J G; Harrison, S M; Monahan, F J

    2016-12-01

    Low-fat meat products could be excellent carriers for plant sterols, known for their cholesterol-lowering properties. In this study, we developed a protocol for the manufacture of a deli-style turkey enriched with plant sterols (S) at a level sufficient to deliver the maximum plant sterols amount recommended for cholesterol reduction by the European Food Safety Authority (3 g of plant sterols per day) in a 70 g portion. We investigated the stability of the plant sterols and the effects of their addition on the product quality. Plant sterols remained stable during the seven-day storage period. The addition of plant sterols significantly affected some texture parameters, shear force, lipid oxidation, L values and water-holding capacity compared with control (C). Sensory analysis was carried out by an untrained panel (32) using the difference-from-control test between C and S samples to evaluate first the extent of the overall sensory difference and then the extent of sensory difference on colour, texture and flavour. Results indicated that panellists considered the intensity of the difference between C and S samples to be 'small'. Plant sterols could be used as a potential health-promoting meat ingredient with no effect on plant sterol stability but with some effects on texture and sensory characteristics. © The Author(s) 2016.

  1. Criticality safety study of shutdown diffusion cascade coolers

    International Nuclear Information System (INIS)

    Paschal, L.S.; Basoglu, B.; Bentley, C.L.; Dunn, M.E.

    1996-01-01

    Gaseous diffusion plants use cascade coolers in the production of highly enriched uranium (HEU) to remove heat from the enriched stream of UF 6 . The cascade coolers operate like shell and tube heat exchangers with the UF 6 on the shell side and Freon on the tube side. Recirculating cooling water (RCW) in condensers is used to cool the Freon. A criticality safety analysis was previously performed for cascade coolers during normal operation. The purpose of this paper is to evaluate several different hypothetical accidents regarding RCW ingress into the cooler to determine whether criticality safety concerns exist

  2. Status report - expert knowledge of operators in fuel reprocessing plants, enrichment plants and fuel fabrication plants

    International Nuclear Information System (INIS)

    Preuss, W.; Kramer, J.; Wildberg, D.

    1987-01-01

    The necessary qualifications of the responsible personnel and the knowledge required by personnel otherwise employed in nuclear plants are among the requirements for licensing laid down in paragraph 7 of the German Atomic Energy Act. The formal regulations for nuclear power plants are not directly applicable to plants in the fuel cycle because of the differences in the technical processes and the plant and work organisation. The aim of the project was therefore to establish a possible need for regulations for the nuclear plants with respect to the qualification of the personnel, and to determine a starting point for the definition of the required qualifications. An extensive investigation was carried out in the Federal Republic of Germany into: the formal requirements for training; the plant and personnel organisation structures; the tasks carried out by the responsible and otherwise employed personnel; and the state of training. For this purpose plant owners and managers were interviewed and the literature and plant specific documentation (e.g. plant rules) were reviewed. On the basis of literature research, foreign practices were determined and used to make comparative evaluations. The status report is divided into three separate parts for the reprocessing, the uranium enrichment, and the manufacture of the fuel elements. On the basis of the situation for reprocessing plants (particularly that of the WAK) and fuel element manufacturing plants, the development of a common (not uniform) regulation for all the examined plants in the fuel cycle was recommended. The report gives concrete suggestions for the content of the regulations. (orig.) [de

  3. Diffusion model of solid particles in a gaseous atmosphere. Pt. 1

    International Nuclear Information System (INIS)

    Fernandez Ruiz, J.L.

    1987-01-01

    Starting from Voinov and Garipov's lagrangian statements on the problem of dynamic evolution of bubbles in liquids, this work is trying to determine some diffusion equations of solid particles in little dense matter like gases or liquids, aiming at applying it to the tracing of matter in atmospheric diffusion and the tracing of corpuscles in liquids. All the resulting equations lead to a solution given as a tensor θ ij related to the velocity states v i defined as v i = , and to the potential from which derive. One has had in mind the factor of mutual correlation between the diffusing particles. This increases the scope of application of these equations to Chemistry and to Biomedical Sciences. (author)

  4. Environmental Development Plan: uranium enrichment

    International Nuclear Information System (INIS)

    1979-09-01

    This Environmental Development Plan identifies and examines the environmental, health, safety, and socioeconomic concerns and corresponding requirements associated with the DOE research, development, demonstration, and operation of the Uranium Enrichment program, including the gaseous diffusion process, the centrifuge process, centrifuge rotor fabrication, and related research and development activities

  5. DIFFUSIVE EXCHANGE OF GASEOUS POLYCYCLIC AROMATIC HYDROCARBONS AND POLYCHLORINATED BIPHENYLS ACROSS THE AIR-WATER INTERFACE OF THE CHESAPEAKE BAY. (R825245)

    Science.gov (United States)

    Dissolved and gas-phase concentrations of nine polycyclic aromatic hydrocarbons and 46 polychlorinated biphenyl congeners were measured at eight sites on the Chesapeake Bay at four different times of the year to estimate net diffusive air-water gas exchange rates. Gaseous PAHs ar...

  6. Multi-detector system approach for unattended uranium enrichment monitoring at gas centrifuge enrichment plants

    Science.gov (United States)

    Favalli, A.; Lombardi, M.; MacArthur, D. W.; McCluskey, C.; Moss, C. E.; Paffett, M. T.; Ianakiev, K. D.

    2018-01-01

    Improving the quality of safeguards measurements at Gas Centrifuge Enrichment Plants while reducing the inspection effort is an important objective given the number of existing and new plants that need to be safeguarded. A useful tool in many safeguards approaches is the on-line monitoring of enrichment in process pipes. One requirement of such a monitor is a simple, reliable and precise passive measurement of the 186-keV line from 235U. The other information required is the amount of gas in the pipe, which can be obtained by a transmission or pressure measurement. We describe our research to develop such a passive measurement system. Unfortunately, a complication arises in the interpretation of the gamma measurements, from the contribution of uranium deposits on the wall of the pipe to the 186-keV peak. A multi-detector approach to address this complication is presented where two measurements, one with signal primarily from gas and one with signal primarily from deposits, are performed simultaneously with different detectors and geometries. This allows a correction to be made to the 186-keV peak for the contribution from the deposit. We present the design of the multi-detector system and the results of the experimental calibration of the proof-of-principle prototype built at LANL.

  7. Multi-detector system approach for unattended uranium enrichment monitoring at gas centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Favalli, A.; Lombardi, M.; MacArthur, D. W.; McCluskey, C.; Moss, C. E.

    2017-01-01

    Improving the quality of safeguards measurements at Gas Centrifuge Enrichment Plants while reducing the inspection effort is an important objective given the number of existing and new plants that need to be safeguarded. A useful tool in many safeguards approaches is the on-line monitoring of enrichment in process pipes. One requirement of such a monitor is a simple, reliable and precise passive measurement of the 186-keV line from 235 U. The other information required is the amount of gas in the pipe, which can be obtained by a transmission or pressure measurement. Here, we describe our research to develop such a passive measurement system. Unfortunately, a complication arises in the interpretation of the gamma measurements, from the contribution of uranium deposits on the wall of the pipe to the 186-keV peak. A multi-detector approach to address this complication is presented where two measurements, one with signal primarily from gas and one with signal primarily from deposits, are performed simultaneously with different detectors and geometries. This allows a correction to be made to the 186-keV peak for the contribution from the deposit. Finally, we present the design of the multi-detector system and the results of the experimental calibration of the proof-of-principle prototype built at LANL.

  8. Phytotoxicity and Plant Productivity Analysis of Tar-Enriched Biochars

    Science.gov (United States)

    Keller, M. L.; Masiello, C. A.; Dugan, B.; Rudgers, J. A.; Capareda, S. C.

    2008-12-01

    Biochar is one of the three by-products obtained by the pyrolysis of organic material, the other two being syngas and bio-oil. The pyrolysis of biomass has generated a great amount of interest in recent years as all three by-products can be put toward beneficial uses. As part of a larger project designed to evaluate the hydrologic impact of biochar soil amendment, we generated a biochar through fast pyrolysis (less than 2 minutes) of sorghum stock at 600°C. In the initial biochar production run, the char bin was not purged with nitrogen. This inadvertent change in pyrolysis conditions produced a fast-pyrolysis biochar enriched with tars. We chose not to discard this batch, however, and instead used it to test the impact of tar-enriched biochars on plants. A suite of phytotoxicity tests were run to assess the effects of tar-rich biochar on plant germination and plant productivity. We designed the experiment to test for negative effects, using an organic carbon and nutrient-rich, greenhouse- optimized potting medium instead of soil. We used Black Seeded Simpson lettuce (Lactuca sativa) as the test organism. We found that even when tars are present within biochar, biochar amendment up to 10% by weight caused increased lettuce germination rates and increased biomass productivity. In this presentation, we will report the statistical significance of our germination and biomass data, as well as present preliminary data on how biochar amendment affects soil hydrologic properties.

  9. Application of wet effluent diffusion denuder for measurement of uptake coefficient of gaseous pollutants

    Czech Academy of Sciences Publication Activity Database

    Motyka, K.; Mikuška, Pavel; Večeřa, Zbyněk

    2011-01-01

    Roč. 84, č. 2 (2011), s. 519-523 ISSN 0039-9140 R&D Projects: GA MŽP SP/1A3/148/08; GA MŽP SP/1A3/55/08; GA MŽP SP/1B7/189/07 Institutional research plan: CEZ:AV0Z40310501 Keywords : collection efficiency * wet effluent diffusion denuder * uptake coefficient Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.794, year: 2011

  10. Projected uranium measurement uncertainties for the Gas Centrifuge Enrichment Plant

    International Nuclear Information System (INIS)

    Younkin, J.M.

    1979-02-01

    An analysis was made of the uncertainties associated with the measurements of the declared uranium streams in the Portsmouth Gas Centrifuge Enrichment Plant (GCEP). The total uncertainty for the GCEP is projected to be from 54 to 108 kg 235 U/year out of a measured total of 200,000 kg 235 U/year. The systematic component of uncertainty of the UF 6 streams is the largest and the dominant contributor to the total uncertainty. A possible scheme for reducing the total uncertainty is given

  11. Safeguards approaches for conversion and gas centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Stanuch, C.; Whitaker, M.; Lockwood, D.; Boyer, B.

    2013-01-01

    This paper describes recent studies and investigations of new safeguards measures and inspection tools to strengthen international safeguards at GCEPs (Gas Centrifuge Enrichment Plants) and conversion plants. The IAEA has indicated that continuous, unattended process monitoring should play a central role in future safeguards approaches for conversion plants and GCEPs. Monitoring safeguards relevant information from accountancy scales, process load cells, and unit header pipes can make existing safeguards approaches more efficient by replacing repetitive, routine, labor-intensive inspection activities with automated systems. These systems can make the safeguards approach more effective by addressing more completely the safeguards objectives at these facilities. Automated collection and analysis of the data can further enable the IAEA to move towards a fully-information driven inspection regime with randomized (from the operator's perspective), short-notice inspections. The reduction in repetitive on-site inspection activities would also be beneficial to plant operators, but only if sensitive and proprietary information can be protected and the new systems prove to be reliable. New facilities that incorporate Safeguards by Design into the earliest design stages can facilitate the effective DIV (Design Information Verification) of the plant to allow the inspectors to analyze the capacity of the plant, to project maximum production from the plant, and to provide a focus on the areas in the plant where credible diversion scenarios could be attempted. Facilitating efficient nuclear material accountancy by simplifying process pipework and making flow measurement points more accessible can allow for easier estimation of plant holdup and a potential reduction in the number of person-days of inspection. Lastly, a universal monitoring standard that tracks the location, movement, and use of UF 6 cylinders may enhance the efficiency of operations at industry sites and would

  12. Modified micro-diffusion method for 15N-enriched soil solutions

    International Nuclear Information System (INIS)

    Aigner, M.

    2000-01-01

    The preparation of solutions for determination of 15 N/ 14 N isotope ratios is described, with special reference to dilute samples. A micro-diffusion method has been simplified to be more suitable for rapid isotope-ratio determination in soil solutions collected in tensionics. Ammonia expelled during micro-diffusion is captured on acidified filter discs fixed to the caps of gas-tight vials. The discs are transferred to tin capsules for shipment to the Soil Science Unit for 15 N-enrichment determination. (author)

  13. Depletion of atmospheric gaseous elemental mercury by plant uptake at Mt. Changbai, Northeast China

    Directory of Open Access Journals (Sweden)

    X. Fu

    2016-10-01

    Full Text Available There exists observational evidence that gaseous elemental mercury (GEM can be readily removed from the atmosphere via chemical oxidation followed by deposition in the polar and sub-polar regions, free troposphere, lower stratosphere, and marine boundary layer under specific environmental conditions. Here we report GEM depletions in a temperate mixed forest at Mt. Changbai, Northeast China. The strong depletions occurred predominantly at night during the leaf-growing season and in the absence of gaseous oxidized mercury (GOM enrichment (GOM  <  3 pg m−3. Vertical gradients of decreasing GEM concentrations from layers above to under forest canopy suggest in situ loss of GEM to forest canopy at Mt. Changbai. Foliar GEM flux measurements showed that the foliage of two predominant tree species is a net sink of GEM at night, with a mean flux of −1.8 ± 0.3 ng m2 h−1 over Fraxinus mandshurica (deciduous tree species and −0.1 ± 0.2 ng m2 h−1 over Pinus Koraiensis (evergreen tree species. Daily integrated GEM δ202Hg, Δ199Hg, and Δ200Hg at Mt. Changbai during 8–18 July 2013 ranged from −0.34 to 0.91 ‰, from −0.11 to −0.04 ‰ and from −0.06 to 0.01 ‰, respectively. A large positive shift in GEM δ202Hg occurred during the strong GEM depletion events, whereas Δ199Hg and Δ200Hg remained essentially unchanged. The observational findings and box model results show that uptake of GEM by forest canopy plays a predominant role in the GEM depletion at Mt. Changbai forest. Such depletion events of GEM are likely to be a widespread phenomenon, suggesting that the forest ecosystem represents one of the largest sinks ( ∼ 1930 Mg of atmospheric Hg on a global scale.

  14. Hard Surface Layers by Pack Boriding and Gaseous Thermo-Reactive Deposition and Diffusion Treatments

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lundin; Bottoli, Federico; Dahl, Kristian Vinter

    2017-01-01

    ) layers with hardnesses up to 1800 HV. Titanizing of ARNE tool steel results in a surface layer consisting of TiC with a hardness of approximately 4000 HV. Duplex treatments, where boriding is combined with subsequent (TRD) titanizing, result in formation of hard TiB2 on top of a thick layer of Fe......Thermo-reactive deposition and diffusion (TRD) and boriding are thermochemical processes that result in very high surface hardness by conversion of the surface into carbides/nitrides and borides, respectively. These treatments offer significant advantages in terms of hardness, adhesion, tribo...... subjected to TRD (chromizing and titanizing) and boriding treatments. For the steels with low carbon content, chromizing results in surface alloying with chromium, i.e., formation of a (soft) “stainless” surface zone. Steels containing higher levels of carbon form chromium carbide (viz. Cr23C6, Cr7C3...

  15. Fuel rich and fuel lean catalytic combustion of the stabilized confined turbulent gaseous diffusion flames over noble metal disc burners

    Directory of Open Access Journals (Sweden)

    Amal S. Zakhary

    2014-03-01

    Full Text Available Catalytic combustion of stabilized confined turbulent gaseous diffusion flames using Pt/Al2O3 and Pd/Al2O3 disc burners situated in the combustion domain under both fuel-rich and fuel-lean conditions was experimentally studied. Commercial LPG fuel having an average composition of: 23% propane, 76% butane, and 1% pentane was used. The thermal structure of these catalytic flames developed over Pt/Al2O3 and Pd/Al2O3 burners were examined via measuring the mean temperature distribution in the radial direction at different axial locations along the flames. Under-fuel-rich condition the flames operated over Pt catalytic disc attained high temperature values in order to express the progress of combustion and were found to achieve higher activity as compared to the flames developed over Pd catalytic disc. These two types of catalytic flames demonstrated an increase in the reaction rate with the downstream axial distance and hence, an increase in the flame temperatures was associated with partial oxidation towards CO due to the lack of oxygen. However, under fuel-lean conditions the catalytic flame over Pd catalyst recorded comparatively higher temperatures within the flame core in the near region of the main reaction zone than over Pt disc burner. These two catalytic flames over Pt and Pd disc burners showed complete oxidation to CO2 since the catalytic surface is covered by more rich oxygen under the fuel-lean condition.

  16. Species specificity of resistance to oxygen diffusion in thin cuticular membranes from amphibious plants

    DEFF Research Database (Denmark)

    Frost-Christensen, Henning; Jørgensen, Lise Bolt; Floto, Franz

    2003-01-01

    oxygen, diffusion, cuticula, amphibious plants, Hygrophila, Berula, Lobelia, Mentha, Potamogeton, Veronica, aquatic plants, submerged plants......oxygen, diffusion, cuticula, amphibious plants, Hygrophila, Berula, Lobelia, Mentha, Potamogeton, Veronica, aquatic plants, submerged plants...

  17. Long-term disposal of enrichment plant tails

    International Nuclear Information System (INIS)

    1979-08-01

    Approximately 97% of the uranium fed to the isotope separation plants is recovered as tails containing nominally 0.2 wt percent U-235. Essentially all this tails material produced in the past, as well as that currently being generated, is stored as solidified UF 6 in steel cylinders. This report describes a stand-alone, 10 tU/day facility for converting the UF 6 to a stable uranium oxide powder amenable to long-term storage in steel drums. The conversion is accomplished in a two-step process in which the UF 6 is first reduced to UF 4 with hydrogen in a tower reactor and then the UF 4 is pyrohydrolyzed to UO 2 with steam in a three-stage screw reactor. One reduction reactor supplies the feed for three pyrohydrolysis reactor lines. Included in the process flow sheets and reactor design details are descriptions of the major auxiliary components for vaporizing and feeding the UF 6 , a dissociator for ammonia used as a hydrogen source, a system for recovering anhydrous hydrogen fluoride, and a reactor system for the disposal of hydrous hydrogen fluoride. Two of the nominal 10 tU/day plants would be required to handle the tails produced in isotope separation plants supplying enriched uranium to a nuclear power industry with a generation capacity of 50 GWe per year

  18. U.S. forms uranium enrichment corporation

    International Nuclear Information System (INIS)

    Seltzer, R.

    1993-01-01

    After almost 40 years of operation, the federal government is withdrawing from the uranium enrichment business. On July 1, the Department of Energy turned over to a new government-owned entity--the US Enrichment Corp. (USEC)--both the DOE enrichment plants at Paducah, Ky., and Portsmouth, Ohio, and domestic and international marketing of enriched uranium from them. Pushed by the inability of DOE's enrichment operations to meet foreign competition, Congress established USEC under the National Energy Policy Act of 1992, envisioning the new corporation as the first step to full privatization. With gross revenues of $1.5 billion in fiscal 1992, USEC would rank 275th on the Fortune 500 list of top US companies. USEC will lease from DOE the Paducah and Portsmouth facilities, built in the early 1950s, which use the gaseous diffusion process for uranium enrichment. USEC's stock is held by the US Treasury, to which it will pay annual dividends. Martin Marietta Energy Systems, which has operated Paducah since 1984 and Portsmouth since 1986 for DOE, will continue to operate both plants for USEC. Closing one of the two facilities will be studied, especially in light of a 40% world surplus of capacity over demand. USEC also will consider other nuclear-fuel-related ventures. USEC will produce only low-enriched uranium, not weapons-grade material. Indeed, USEC will implement a contract now being completed under which the US will purchase weapons-grade uranium from dismantled Russian nuclear weapons and convert it into low-enriched uranium for power reactor fuel

  19. Systems approach used in the Gas Centrifuge Enrichment Plant

    International Nuclear Information System (INIS)

    Rooks, W.A. Jr.

    1982-01-01

    A requirement exists for effective and efficient transfer of technical knowledge from the design engineering team to the production work force. Performance-Based Training (PBT) is a systematic approach to the design, development, and implementation of technical training. This approach has been successfully used by the US Armed Forces, industry, and other organizations. The advantages of the PBT approach are: cost-effectiveness (lowest life-cycle training cost), learning effectiveness, reduced implementation time, and ease of administration. The PBT process comprises five distinctive and rigorous phases: Analysis of Job Performance, Design of Instructional Strategy, Development of Training Materials and Instructional Media, Validation of Materials and Media, and Implementation of the Instructional Program. Examples from the Gas Centrifuge Enrichment Plant (GCEP) are used to illustrate the application of PBT

  20. Systems approach used in the Gas Centrifuge Enrichment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Rooks, W.A. Jr.

    1982-01-01

    A requirement exists for effective and efficient transfer of technical knowledge from the design engineering team to the production work force. Performance-Based Training (PBT) is a systematic approach to the design, development, and implementation of technical training. This approach has been successfully used by the US Armed Forces, industry, and other organizations. The advantages of the PBT approach are: cost-effectiveness (lowest life-cycle training cost), learning effectiveness, reduced implementation time, and ease of administration. The PBT process comprises five distinctive and rigorous phases: Analysis of Job Performance, Design of Instructional Strategy, Development of Training Materials and Instructional Media, Validation of Materials and Media, and Implementation of the Instructional Program. Examples from the Gas Centrifuge Enrichment Plant (GCEP) are used to illustrate the application of PBT.

  1. Expansion of U. S. uranium enrichment capacity. Final environmental statement

    Energy Technology Data Exchange (ETDEWEB)

    1976-04-01

    Reasonably foreseeable environmental, social, economic, and technological costs and benefits of postulated expansion of U. S. enrichment capacity through the year 2000 and reasonably available alternatives to such expansion are described. Both the gas centrifuge and gaseous diffusion methods for the enrichment of uranium are considered in this impact assessment. (JGB)

  2. Examination of vegetation around a nuclear plant emitting gaseous fluorides in order to detect fluorine pollution

    International Nuclear Information System (INIS)

    Teulon, Francoise; Bonnaventure, J. P.

    1971-08-01

    Fluorine pollution (chronic or occasional) around a plant rejecting gaseous fluoride effluents can be detected from vegetation samples by chemical analysis. Systematic monitoring allows the effects and gravity of the pollution to be estimated. The analytical method used consists of a double distillation (in phosphoric acid and perchloric acid) followed by a spectro-colorimetric analysis (alizarine-complexon-lanthane). This method of control allows both the efficiency of the trapping installations and also the appearance of effluents at unexpected places to be checked, In the event of an accident it is possible to determine the advisability of prohibiting the consumption of locally grown produce by humans or fodder by cattle. Research conducted in order to determine the relation between visible, damage to certain vegetables (tomatoes, haricot beans and sorghum) and their fluorine contents demonstrated that such a relation appears above all at the level of the leaves; chemical analysis may thus be used to confirm or reject information obtained on the basis of visual evidence [fr

  3. Trace analysis of halogenated hydrocarbons in gaseous samples by on-line enrichment in an adsorption trap, on-column cold-trapping and capillary gas chromatography. I.Method and instrumentation

    NARCIS (Netherlands)

    Noij, T.H.M.; Fabian, P.; Borchers, R.; Janssen, F.; Cramers, C.A.M.G.; Rijks, J.A.

    1987-01-01

    A method is described for the determination of halocarbons in gaseous samples down to the ppt level (1:1012, v/v), consisting of successive on-line sub-ambient enrichment on an adsorbent, on-column cryofocusing, capillary gas chromatography and electron-capture detection. The quantitative aspects of

  4. Uranium-236 in light water reactor spent fuel recycled to an enriching plant

    International Nuclear Information System (INIS)

    de la Garza, A.

    1977-01-01

    The introduction of 236 U to an enriching plant by recycling spent fuel uranium results in enriched products containing 236 U, a parasitic neutron absorber in reactor fuel. Convenient approximate methodology determines 235 236 U, and total uranium flowsheets with associated separative work requirements in enriching plant operations for use by investigators of the light water reactor fuel cycle not having recourse to specialized multicomponent cascade technology. Application of the methodology has been made to compensation of an enriching plant product for 236 U content and to the value at an enriching plant of spent fuel uranium. The approximate methodology was also confirmed with more exact calculations and with some experience with 236 U in an enriching plant

  5. Enrichment of heavy water in thermal-diffusion columns connected in series

    International Nuclear Information System (INIS)

    Yeh, Ho-Ming; Chen, Liu Yi

    2009-01-01

    The separation equations for enrichment of heavy water from water isotope mixture by thermal diffusion in multiple columns connected in series, have been derived based on one column design developed in previous work. The improvement in separation is achievable by operating in a double-column device, instead of in a single-column device, with the same total column length. It is also found that further improvement in separation is obtainable if a triple-column device is employed, except for operating under small total column length and low flow rate.

  6. Enriched reproducing kernel particle method for fractional advection-diffusion equation

    Science.gov (United States)

    Ying, Yuping; Lian, Yanping; Tang, Shaoqiang; Liu, Wing Kam

    2018-06-01

    The reproducing kernel particle method (RKPM) has been efficiently applied to problems with large deformations, high gradients and high modal density. In this paper, it is extended to solve a nonlocal problem modeled by a fractional advection-diffusion equation (FADE), which exhibits a boundary layer with low regularity. We formulate this method on a moving least-square approach. Via the enrichment of fractional-order power functions to the traditional integer-order basis for RKPM, leading terms of the solution to the FADE can be exactly reproduced, which guarantees a good approximation to the boundary layer. Numerical tests are performed to verify the proposed approach.

  7. Uranium enrichment by gas centrifuge

    International Nuclear Information System (INIS)

    Heriot, I.D.

    1988-01-01

    After recalling the physical principles and the techniques of centrifuge enrichment the report describes the centrifuge enrichment programmes of the various countries concerned and compares this technology with other enrichment technologies like gaseous diffusion, laser, aerodynamic devices and chemical processes. The centrifuge enrichment process is said to be able to replace with advantage the existing enrichment facilities in the short and medium term. Future prospects of the process are also described, like recycled uranium enrichment and economic improvements; research and development needs to achieve the economic prospects are also indicated. Finally the report takes note of the positive aspect of centrifuge enrichment as far as safeguards and nuclear safety are concerned. 27 figs, 113 refs

  8. Modifying woody plants for efficient conversion to liquid and gaseous fuels

    Energy Technology Data Exchange (ETDEWEB)

    Dinus, R.J.; Dimmel, D.R.; Feirer, R.P.; Johnson, M.A.; Malcolm, E.W. (Institute of Paper Science and Technology, Atlanta, GA (USA))

    1990-07-01

    The Short Rotation Woody Crop Program (SRWCP), Department of Energy, is developing woody plant species as sources of renewable energy. Much progress has been made in identifying useful species, and testing site adaptability, stand densities, coppicing abilities, rotation lengths, and harvesting systems. Conventional plant breeding and intensive cultural practices have been used to increase above-ground biomass yields. Given these and foreseeable accomplishments, program leaders are now shifting attention to prospects for altering biomass physical and chemical characteristics, and to ways for improving the efficiency with which biomass can be converted to gaseous and liquid fuels. This report provides a review and synthesis of literature concerning the quantity and quality of such characteristics and constituents, and opportunities for manipulating them via conventional selection and breeding and/or molecular biology. Species now used by SRWCP are emphasized, with supporting information drawn from others as needed. Little information was found on silver maple (Acer saccharinum), but general comparisons (Isenberg 1981) suggest composition and behavior similar to those of the other species. Where possible, conclusions concerning means for and feasibility of manipulation are given, along with expected impacts on conversion efficiency. Information is also provided on relationships to other traits, genotype X environment interactions, and potential trade-offs or limitations. Biomass productivity per se is not addressed, except in terms of effects that may by caused by changes in constituent quality and/or quantity. Such effects are noted to the extent they are known or can be estimated. Likely impacts of changes, however effected, on suitability or other uses, e.g., pulp and paper manufacture, are notes. 311 refs., 4 figs., 9 tabs.

  9. Recent developments in the United States uranium enrichment enterprise

    International Nuclear Information System (INIS)

    Longenecker, J.R.

    1987-01-01

    In the near term, DOE is reducing production costs at the gaseous diffusion plants (GDPs), and we've made significant progress already. GDP production costs are expected to decline even further in the near future. DOE is also negotiating new power contracts for the GDPs. The new power contracts, capital improvements, and the use of more unfirm power should reduce our GDP average cost of production to about $60/SWU in the 1990s. Significant technical progress on the Atomic Vapor Laser Isotope Separation (AVLIS) advanced enrichment technology has been made recently. The highlight has been a series of half-scale integrated enrichment experiments using the Laser Demonstration Facility and the Mars separator. We are also ready to initiate testing in the full-scale Separator Demonstration Facility, including a 100 hour run that will vaporize over 5 tons of uranium. DOE is developing plans to restructure the enterprise into a more businesslike entity. The key objective in 1987 is to work with Congress to advance the restructuring of the U.S. uranium enrichment enterprise, to assure its long term competitiveness. We hope to establish in law the charter, objectives, and goals for the restructured enterprise. DOE expects that the world price for enrichment services will continue to decrease in the future. There should be sufficient excess enrichment capacity in the future to assure that competition will be keen. Such a healthy, competitive, world enrichment market will be beneficial to both suppliers and consumers of uranium enrichment services. (J.P.N.)

  10. Profile of World Uranium Enrichment Programs-2009

    International Nuclear Information System (INIS)

    Laughter, Mark D.

    2009-01-01

    It is generally agreed that the most difficult step in building a nuclear weapon is acquiring fissile material, either plutonium or highly enriched uranium (HEU). Plutonium is produced in a nuclear reactor, whereas HEU is produced using a uranium enrichment process. Enrichment is also an important step in the civil nuclear fuel cycle, in producing low enriched uranium (LEU) for use as fuel for nuclear reactors to generate electricity. However, the same equipment used to produce LEU for nuclear reactor fuel can also be used to produce HEU for weapons. Safeguards at an enrichment plant are the array of assurances and verification techniques that ensure uranium is not diverted or enriched to HEU. There are several techniques for enriching uranium. The two most prevalent are gaseous diffusion, which uses older technology and requires a lot of energy, and gas centrifuge separation, which uses more advanced technology and is more energy efficient. Gaseous diffusion plants (GDPs) provide about 40% of current world enrichment capacity but are being phased out as newer gas centrifuge enrichment plants (GCEPs) are constructed. Estimates of current and future enrichment capacity are always approximate, due to the constant upgrades, expansions, and shutdowns occurring at enrichment plants, largely determined by economic interests. Currently, the world enrichment capacity is approximately 56 million kilogram separative work units (SWU) per year, with 22.5 million in gaseous diffusion and more than 33 million in gas centrifuge plants. Another 34 million SWU/year of capacity is under construction or planned for the near future, almost entirely using gas centrifuge separation. Other less-efficient techniques have also been used in the past, including electromagnetic and aerodynamic separations, but these are considered obsolete, at least from a commercial perspective. Laser isotope separation shows promise as a possible enrichment technique of the future but has yet to be

  11. New Measures to Safeguard Gas Centrifuge Enrichment Plants

    Energy Technology Data Exchange (ETDEWEB)

    Whitaker, Jr., James [ORNL; Garner, James R [ORNL; Whitaker, Michael [ORNL; Lockwood, Dunbar [U.S. Department of Energy, NNSA; Gilligan, Kimberly V [ORNL; Younkin, James R [ORNL; Hooper, David A [ORNL; Henkel, James J [ORNL; Krichinsky, Alan M [ORNL

    2011-01-01

    As Gas Centrifuge Enrichment Plants (GCEPs) increase in separative work unit (SWU) capacity, the current International Atomic Energy Agency (IAEA) model safeguards approach needs to be strengthened. New measures to increase the effectiveness of the safeguards approach are being investigated that will be mutually beneficial to the facility operators and the IAEA. One of the key concepts being studied for application at future GCEPs is embracing joint use equipment for process monitoring of load cells at feed and withdrawal (F/W) stations. A mock F/W system was built at Oak Ridge National Laboratory (ORNL) to generate and collect F/W data from an analogous system. The ORNL system has been used to collect data representing several realistic normal process and off-normal (including diversion) scenarios. Emphasis is placed on the novelty of the analysis of data from the sensors as well as the ability to build information out of raw data, which facilitates a more effective and efficient verification process. This paper will provide a progress report on recent accomplishments and next steps.

  12. Measurement of the enrichment of uranium-hexafluoride gas in product pipes in the centrifuge enrichment plant at Almelo

    International Nuclear Information System (INIS)

    Packer, T.W.; Lees, E.W.; Aaldijk, J.K.; Harry, R.J.S.

    1987-09-01

    One of the objectives of safeguarding centrifuge enrichment plants is to apply non-destructive measurements inside the cascade area to confirm that the enrichment level is in the low enriched uranium range. Research in the UK and USA has developed a NDA instrument which can confirm the presence of low enriched uranium on a rapid go/no go basis in cascade header pipework of their centrifuge enrichment plants. The instrument is based on a gamma spectroscopic measurement coupled with an X-ray fluorescence analysis. This report gives the results of measurements carried out at Almelo by the UKAEA Harwell, ECN Petten and KFA Juelich to determine if these techniques could be employed at Almelo and Gronau. The energy dispersive X-ray fluorescence analysis has been applied to determine the total mass of uranium in the gas phase, and the deposit correction technique and the two geometry technique have been applied at Almelo to correct the measured gamma intensities for those emitted by the deposit. After an executive summary the report discusses the principles of the two correction methods. A short description of the equipment precedes the presentation of the results of the measurements and the discussion. After the conclusions the report contains two appendices which contain the derivation of the formulae for the deposit correction technique and a discussion of the systematic errors of this technique. 8 figs.; 11 refs.; 6 tables

  13. Disposition of highly enriched uranium obtained from the Republic of Kazakhstan. Environmental assessment

    International Nuclear Information System (INIS)

    1995-05-01

    This EA assesses the potential environmental impacts associated with DOE's proposal to transport 600 kg of Kazakhstand-origin HEU from Y-12 to a blending site (B ampersand W Lynchburg or NFS Erwin), transport low-enriched UF6 blending stock from a gaseous diffusion plant to GE Wilmington and U oxide blending stock to the blending site, blending the HEU and uranium oxide blending stock to produce LEU in the form of uranyl nitrate, and transport the uranyl nitrate from the blending site to USEC Portsmouth

  14. Modeling of Transients in an Enrichment Circuit

    International Nuclear Information System (INIS)

    Fernandino, Maria; Delmastro, Dario; Brasnarof, Daniel

    2003-01-01

    In the present work a mathematical model is presented in order to describe the dynamic behavior inside a closed enrichment loop, the latter representing a single stage of an uranium gaseous diffusion enrichment cascade.The analytical model is turned into a numerical model, and implemented through a computational code.Transients of two species separation were numerically analyzed, including setting times of each magnitude, behavior of each one of them during different transients, and redistribution of concentrations along the closed loop

  15. Radioisotope devices at Novo-Krivorozhskij-ore-enrichment plant

    International Nuclear Information System (INIS)

    Levitskij, V.Ya.; Kucher, V.G.; Ministerstvo Chernoj Metallurgii Ukrainskoj SSR, Dnepropetrovsk, Bazovaya Opytno-Konstruktorskaya Izotopnaya lab.)

    1975-01-01

    Use of the ''Ferrite'' analyzers, AZhR and PAZh-1 and the GR-7 gamma relay in different engineering areas of the Novo-Krivorozh ore-enrichment plant is evaluated. The ''Ferrite'' radioisotopic analyzer was designed for rapid roentgeno-radiometric determination of the total iron and iron group element contents in powdered samples of ores and products of their treatment. From the density of the flux of the characteristic radiation it is possible to determine quantitatively the content of the element of interest in the analyzed material. The radioisotpic analyzer AZhR-1 is distinguished by its high efficiency in the analysis for total iron on products of processing of iron ore raw materials. The use of this apparatus allows complete replacement of the chemical method for rapid analysis of concentrates by the roentgeno-radiometric method, which decreases the total analytical work on determination of total iron and speeds up output of information on concentrate quality. The radioisotopic gamma analyzer PAZh-1 is designed for automatic and either continuous or discrete measurement of the total iron content in iron ore materials ground to 50 mm, carried on a conveyor, without selection or preparation of the samples for analysis. The analyzer operates on the principle of measuring the average frequency of impingement on a detector of gamma quanta back-scattered by the analyzed material. This frequency is determined by the percentage content of total iron in the material. The apparatus operates continuously. The mean square deviation of the apparatus values from chemical data is 0.93% Fesub(total). Use of the apparatus greatly increases the operativeness of the control and decreases the laboriousness of raw material sampling in an engineering stream. The radioisotopic data units GR-7 are designed for control of the level of materials in hoppers for recovery and burning of agglomerates. Use of this apparatus showed its great advantage over data units of other types

  16. Competitiveness through change: institutional restructuring of the United States uranium enrichment enterprise

    International Nuclear Information System (INIS)

    Longenecker, J.R.

    1987-01-01

    The position of the United States programme of uranium enrichment under the Department of Energy is explained. Its competitiveness has improved over the past few years by normalising supply and demand and by streamlining the costs of gaseous diffusion plant production. The historical aspects of the uranium enrichment service are explained. Revised criteria to describe the guidelines to cover pricing, contracting and other crucial functions are under discussion. Two aspects of the new criteria of particular interest -restrictions on foreign-origin uranium and recovery of Government costs - are noted. Possible private sector involvement in uranium enrichment is discussed. Technological innovations are explained and equipment illustrated. These should improve the industry's competitiveness. (U.K.)

  17. UF6 test loop for evaluation and implementation of international enrichment plant safeguards

    International Nuclear Information System (INIS)

    Cooley, J.N.; Fields, L.W.; Swindle, D.W. Jr.

    1987-06-01

    A functional test loop capable of simulating UF 6 flows, pressures, and pipe deposits characteristic of gas centrifuge enrichment plant piping has been designed and fabricated by the Enrichment Safeguards Program of Martin Marietta Energy Systems, Inc., for use by International Atomic Energy Agency (IAEA) at its Safeguards Analytical Laboratory in Seibersdorf, Austria. Purpose of the test loop is twofold: (1) to enable the IAEA to evaluate and to calibrate enrichment safeguards measurement instrumentation to be used in limited frequency-unannounced access (LFUA) inspection strategy measurements at gas centrifuge enrichment plants and (2) to train IAEA inspectors in the use of such instrumentation. The test loop incorporates actual sections of cascade header pipes from the centrifuge enrichment plants subject to IAEA inspections. The test loop is described, applications for its use by the IAEA are detailed, and results from an initial demonstration session using the test loop are summarized

  18. International safeguards at the feed and withdrawal area of a gas centrifuge uranium enrichment plant

    International Nuclear Information System (INIS)

    Gordon, D.M.; Sanborn, J.B.

    1980-01-01

    This paper discusses the application of International Atomic Energy Agency (IAEA) safeguards at a model gas centrifuge uranium enrichment plant designed for the production of low-enriched uranium; particular emphasis is placed upon the verification by the IAEA of the facility material balance accounting. 13 refs

  19. Hyb-Seq: combining target enrichment and genome skimming for plant phylogenomics

    Science.gov (United States)

    Kevin Weitemier; Shannon C.K. Straub; Richard C. Cronn; Mark Fishbein; Roswitha Schmickl; Angela McDonnell; Aaron. Liston

    2014-01-01

    • Premise of the study: Hyb-Seq, the combination of target enrichment and genome skimming, allows simultaneous data collection for low-copy nuclear genes and high-copy genomic targets for plant systematics and evolution studies. • Methods and Results: Genome and transcriptome assemblies for milkweed ( Asclepias syriaca ) were used to design enrichment probes for 3385...

  20. The use of diffusive samplers for collecting organic gaseous constituents in waste gases. Diffusionssammler zur Probenahme von organischen gas- und dampffoermigen Substanzen in Abgasen

    Energy Technology Data Exchange (ETDEWEB)

    Canela, A.; Gruntz, U.; Muehleisen, H.; Tanner, S. (Sandoz AG, Basel (Switzerland). Umweltschutzlaboratorien)

    1990-01-01

    A relatively simple procedure for sample collection of multicomponent organic emissions is presented. A representative part of the waste gas is taken by means of a sampling probe and flows to the coupled sampling device. The gaseous constituents are collected in several diffusive samplers at the bottom of the device. Influencing parameters such as pressure, temperature, gas velocity etc., which may affect the collection rate and therefore the measured values, were investigated in the laboratory. Depending on the analytical detection limit, the sampling time and the diffusion parameters, the method can be applied for the determination of integrated emission concentrations between 0.1 mg/m{sup 3} and 1 g/m{sup 3}. (orig.).

  1. Physics of Fresh Produce Safety: Role of Diffusion and Tissue Reaction in Sanitization of Leafy Green Vegetables with Liquid and Gaseous Ozone-Based Sanitizers.

    Science.gov (United States)

    Shynkaryk, Mykola V; Pyatkovskyy, Taras; Mohamed, Hussein M; Yousef, Ahmed E; Sastry, Sudhir K

    2015-12-01

    Produce safety has received much recent attention, with the emphasis being largely on discovery of how microbes invade produce. However, the sanitization operation deserves more attention than it has received. The ability of a sanitizer to reach the site of pathogens is a fundamental prerequisite for efficacy. This work addresses the transport processes of ozone (gaseous and liquid) sanitizer for decontamination of leafy greens. The liquid sanitizer was ineffective against Escherichia coli K-12 in situations where air bubbles may be trapped within cavities. A model was developed for diffusion of sanitizer into the interior of produce. The reaction rate of ozone with the surface of a lettuce leaf was determined experimentally and was used in a numerical simulation to evaluate ozone concentrations within the produce and to determine the time required to reach different locations. For aqueous ozone, the penetration depth was limited to several millimeters by ozone self-decomposition due to the significant time required for diffusion. In contrast, gaseous sanitizer was able to reach a depth of 100 mm in several minutes without depletion in the absence of reaction with surfaces. However, when the ozone gas reacted with the produce surface, gas concentration was significantly affected. Simulation data were validated experimentally by measuring ozone concentrations at the bottom of a cylinder made of lettuce leaf. The microbiological test confirmed the relationship between ozone transport, its self-decomposition, reaction with surrounding materials, and the degree of inactivation of E. coli K-12. Our study shows that decontamination of fresh produce, through direct contact with the sanitizer, is more feasible with gaseous than with aqueous sanitizers. Therefore, sanitization during a high-speed washing process is effective only for decontaminating the wash water.

  2. Selected nondestructive assay instrumentation for an international safeguards system at uranium enrichment plants

    International Nuclear Information System (INIS)

    Tape, J.W.; Baker, M.P.; Strittmatter, R.; Jain, M.; Evans, M.L.

    1979-01-01

    A selected set of nondestructive assay instruments for an international safeguards system at uranium enrichment plants is currently under development. These instruments are of three types: in-line enrichment meters for feed, product, and tails streams; area radiation monitors for direct detection of high-enriched uranium production, and an enrichment meter for spent alumina trap material. The current status of the development of each of these instruments is discussed, with supporting data, as well as the role each would play in a total international safeguards system. 5 figures

  3. Expansion of U.S. uranium enrichment capacity. Final environmental statement

    International Nuclear Information System (INIS)

    1976-04-01

    Reasonably foreseeable environmental, social, economic, and technological costs and benefits of postulated expansion of U. S. enrichment capacity through the year 2000 and reasonably available alternatives to such expansion are described. Both the gas centrifuge and gaseous diffusion methods for the enrichment of uranium are considered in this impact assessment

  4. Implementation trial of high performance trace analysis/environmental sampling (HPTA/ES) in uranium centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Nackaerts, H.; Kloeckner, W.; Landresse, G.; MacLean, F.; Betti, M.; Forcina, V.; Hiernaut, T.; Tamborini, G.; Koch, L.; Schenkel, R.

    1999-01-01

    Field trials have demonstrated that the analysis of particles upon swipes obtained from inside nuclear installations provides clear signatures of past operations in that installation. This can offer a valuable tool for gaining assurance regarding the compliance with declared activities and the absence of undeclared activities (e.g. enrichment, reprocessing, and reactor operation) at such sites. This method, known as 'Environmental Sampling' (ES) or 'High Performance Trace Analysis' (HPTA) in EURATOM terminology, is at present being evaluated by the EURATOM Safeguards Directorate (ESD) in order to assess its possible use in nuclear installations within the European Union. It is expected that incorporation of HPTA/ES of sample collection and analysis into routine inspection activities will allow EURATOM to improve the effectiveness of safeguards in these installations and hopefully save inspection resources as well. The EURATOM Safeguards Directorate has therefore performed implementation trials involving the collection of particles by the so-called swipe sampling method in uranium centrifuge enrichment plants and hot cells in the European Union. These samples were subsequently analysed by the Joint Research Centre, Institute for Transuranium Elements (ITU) in Karlsruhe. Sampling points were chosen on the basis of the activities performed in the vicinity and by considering the possible ways through which particles are released, diffused and transported. The aim was to test the efficiency of the method as regards: the collection of enough representative material; the identification of a large enough number of uranium particles; the accurate measurement of the enrichment of the uranium particles found on the swipe; the representativity of the results in respect of past activities in the plant; the capability of detecting whether highly enriched uranium has been produced, used or occasionally transported in a location where low enriched uranium is routinely produced in

  5. Present status of centrifuge method for uranium enrichment and PNC plant

    International Nuclear Information System (INIS)

    Nishikido, Yoshikazu

    1977-01-01

    Recentry, the tendency to adopt atomic energy owing to the oil shock, the delay in the construction of nuclear power stations worldwide, the uncertainty in the utilization of plutonium, and the prospect of supplying natural uranium are the situations affecting uranium enrichment. Anyway, the enrichment capacity in the world must be increased by the early years of 1980 s. The uranium enrichment technology by centrifugal method is being developed in various countries under strict control of informations, therefore the details are not known, but the general state in Great Britain, F.R. of Germany, Netherlands, U.S.A. and Japan is explained. The development of the centrifugal enrichment method in Japan was designated in 1972 as the national project aiming at operating the enriching plant with international competitive power by 1985. The PNC undertook the development work, and the research and development include the development of a centrifuge, cascade test, life span test, the development of the mass production technology, and safety test. The especially notable matter in this period was the rapid progress of a supercritical type centrifuge. It is judged that the technical basis for constructing a pilot plant has been established. The site for the pilot plant is being prepared now in the Ningyo Pass Mine, PNC, and the enrichment plant with 7000 centrifuges will be constructed there. The outline of the plant and the schedule for the construction are described. (Kako, I.)

  6. Targeted enrichment strategies for next-generation plant biology

    Science.gov (United States)

    Richard Cronn; Brian J. Knaus; Aaron Liston; Peter J. Maughan; Matthew Parks; John V. Syring; Joshua. Udall

    2012-01-01

    The dramatic advances offered by modem DNA sequencers continue to redefine the limits of what can be accomplished in comparative plant biology. Even with recent achievements, however, plant genomes present obstacles that can make it difficult to execute large-scale population and phylogenetic studies on next-generation sequencing platforms. Factors like large genome...

  7. Development of northern red oak rooted cutting and enrichment planting systems

    Science.gov (United States)

    Matthew H. Gocke; Jamie Schuler; Daniel J. Robison; Barry Goldfarb

    2005-01-01

    Enrichment planting may provide an efficient means to establish elite northern red oak (Quercus rubra L.) genotypes in recently harvested natural forests. However, planting northern red oak (NRO) seedlings into natural stands has proven difficult in the past, especially when competition and other stress factors are not controlled.

  8. Use of diffusive optical fibers for plant lighting

    Energy Technology Data Exchange (ETDEWEB)

    Kozai, T.; Kitaya, Y.; Fujiwara, K. [Chiba Univ., Matsudo (Japan); Kino, S.; Kinowaki, M. [Topy Green Ltd., Tokyo (Japan)

    1994-12-31

    Lighting is one of the most critical aspects in plant production and environmental research with plants. Much research has been repeated on the effect of light intensity, spectral distribution of light and lighting cycle, but comparatively little research done on the effect of lighting direction on the growth, development and morphology of plants. When plants are grown with lamps above, light is directed downward to the plants. Downward or overhead lighting is utilized in almost all cases. However, downward lighting does not always give the best result in terms of lighting efficiency, growth, development and morphology of plants. Kitaya et al. (1988) developed a lighting system in which two rooting beds were arranged; one above and the other under fluorescent lamps. Lettuce plants grew normally in the lower bed and suspended upside-down under the upper bed. The lettuce plants suspended upside-down were given the light in upward direction (upward lighting). No significant difference in growth, development and morphology was found between the lettuce plants grown by the downward and upward lighting. Combining upward and downward lighting, improved spacing efficiency and reduced electricity cost per plant compared with conventional, downward lighting. From the above example, when designing a lighting system for plants with lamps more lighting direction should be considered. In the present study, a sideward lighting system was developed using diffusive optical fiber belts. More higher quality tissue-cultured transplants could be produced in reduced space with sideward lighting system than with a downward lighting system. An application of the sideward lighting system using diffusive optical fiber belts is described and advantages and disadvantages are discussed.

  9. Information system for IAEA inspectors at a centrifuge enrichment plant

    International Nuclear Information System (INIS)

    Baker, A.L.; Tape, J.W.; Picard, R.R.; Strittmatter, R.B.

    1985-01-01

    An information system has been developed to aid International Atomic Energy Agency (IAEA) inspectors at the Portsmouth Gas Centrifuge Plant in the US. This system is designed to provide the inspectors with data storage, data analysis, and data evaluation and decision capabilities with minimal impact on the plant operations. The techniques and methodologies developed for this specific case are described with discussion of their general applicability to IAEA inspections at all types of facilities. 7 refs

  10. Model, parameter and code of environmental dispersion of gaseous effluent under normal operation from nuclear power plant with 600 MWe

    International Nuclear Information System (INIS)

    Hu Erbang; Gao Zhanrong

    1998-06-01

    The model of environmental dispersion of gaseous effluence under normal operation from a nuclear power plant with 600 MWe is established to give a mathematical expression of annual mean atmospheric dispersion factor under mixing release condition based on quality assessment of radiological environment for 30 years of Chinese nuclear industry. In calculation, the impact from calm and other following factors have been taken into account: mixing layer, dry and wet deposition, radioactive decay and buildings. The doses caused from the following exposure pathways are also given by this model: external exposure from immersion cloud and ground deposition, internal exposure due to inhalation and ingestion. The code is named as ROULEA. It contains four modules, i.e. INPUT, ANRTRI, CHIQV and DOSE for calculating 4-dimension joint frequency, annual mean atmospheric dispersion factor and doses

  11. Alternative technologies for meeting uranium enrichment demands

    International Nuclear Information System (INIS)

    Vanstrum, P.R.; Wilcox, W.J. Jr.

    1976-01-01

    The current U.S. program to expand the capacity of gaseous diffusion plants is described and the status of the CIP/CUP programs summarized. Work being conducted on the design of an 8.75-million SWU/y add-on plant to the Portsmouth diffusion cascade is also reported. The status of the U.S. government gas centrifuge program is reported on. Other processes being under evaluation include laser isotope separation and aerodynamic separation. 13 figures

  12. Economic study of an installation for uranium isotope separation by gaseous diffusion; Etude economique d'une installation de separation des isotopes de l'uranium par diffusion gazeuse

    Energy Technology Data Exchange (ETDEWEB)

    Bilous, O [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    This report describes the major problems which arise in the choice of characteristics required in a gaseous diffusion installation for the separation of uranium isotopes. This choice depends largely on economic evaluations, and also on considerations of simplicity. The choice of working pressures and of the characteristics of the membrane are described, as are the possible alternatives regarding the structure of the stages and the problems of control. (author) [French] Ce rapport decrit les problemes majeurs qui se posent dans le choix des caracteristiques d'une installation de diffusion gazeuse destinee a la separation des isotopes de l'uranium. Ce choix depend en grande partie d'evaluations economiques et repose egalement sur des considerations de simplicite. On decrit ainsi le choix des pressions d'operation, celui des caracteristiques de la barriere, les alternatives possibles concernant la structure des etages et les problemes de regulation. (auteur)

  13. Enrichment of Biologically Active Compounds from Selected Plants Using Adsorptive Bubble Separation

    OpenAIRE

    Thompson, Leonor

    2006-01-01

    In this research, foam fractionation a method belonging to the Adsorptive Bubble Separation Methods, was employed to enrich the following active principles contained in medically valuable plants: Faradiol esters from Calendula officinalis, catechins from Camellia sinensis, tryptanthrin from Isatis Tinctoria and cannabinoids from Cannabis sativa. The enrichment methods have been developed in the batch mode for these principles aqueous dilute solutions, based on their physicochemical nature and...

  14. Surfactant-enhanced aquifer remediation at the Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Jackson, R.E.; Londergan, J.T.; Pickens, J.

    1995-01-01

    Many DOE facilities are situated in areas of sand and gravel which have become polluted with dense, non-aqueous phase liquids or DNAPLs, such as chlorinated solvents, from the various industrial operations at these facilities. The presence of such DNAPLs in sand and gravel aquifers is now recognized as the principal factor in the failure of standard ground-water remediation methods, i.e., open-quotes pump-and-treatclose quotes operations, to decontaminate such systems. The principal objective of this study is to demonstrate that multi-component DNAPLs can be readily solubilized in sand and gravel aquifers by dilute surfactant solutions

  15. Evaluation of the proposed pilot groundwater pump and treat demonstration for the Paducah Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Bodenstein, G.W.; Bonczek, R.R.; Early, T.O.; Hale, T.B.; Huff, D.D.; Nickelson, M.D.; Rightmire, C.T.

    1992-11-01

    This report contains the evaluation and recommendations of a Groundwater Corrective Actions Review Team. The primary goal is to evaluate the technical merit of and the need to implement a proposed groundwater pump-and-treat demonstration project for the Northwest contaminant plume at Paducah, Kentucky. A key distinction recognized by the review team is that the proposed project is intended to be a full-scale hydraulic containment of contaminants migrating from the sources of the plume, not plume remediation. The key questions incorporated into this plan are whether (1) dense, nonaqueous-phase liquids (DNAPLS) are present in the Regional Gravel Aquifer (RGA) at the source of the plume and (2) 99 Tc removal must be included as part of any groundwater treatment process. The first question cannot be answered until the contaminant sources are better defined; the second question requires further risk assessment and/or a policy decision by DOE. Technical evaluation by the review team suggests that the recommended course of action be to modify the proposed work plan to include accurate identification of the sources of contaminants and vertical distribution of contaminants within the Northwest plume before a decision is made on the preferred source-control option. If DNAPLs are not present in the RGA, removal or containment of the sources is recommended. If DNAPLs are present, then hydraulic containment will be required. Finally, the review team recognizes that it is necessary to initiate a more comprehensive analysis of sitewide remediation needs to create links between action taken for the Northwest plume and action taken for other contamination sites at PGPD

  16. Environmental program audit, Paducah Gaseous Diffusion Plant, Paducah, Kentucky. Final report

    International Nuclear Information System (INIS)

    1985-08-01

    The environmental monitoring program, environmental control equipment and its use, and the facility's compliance with DOE orders, Federal and State laws and regulations were evaluated in this audit. No imminent threat to public health and safety was discovered. A needed quality assurance program is being added. Recommendations are given

  17. Report on the Biological Monitoring Program at Paducah Gaseous Diffusion Plant, January--December 1995

    Energy Technology Data Exchange (ETDEWEB)

    Kszos, L.A. [ed.

    1996-04-01

    The BMP for PGDP consists of three major tasks: (1) effluent and ambient toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities (benthic macroinvertebrates, fish). This report focuses on ESD activities occurring from Jan. 1995 to Dec. 1995, although activities conducted outside this period are included as appropriate.

  18. Evaluation of the proposed pilot groundwater pump and treat demonstration for the Paducah Gaseous Diffusion Plant

    Energy Technology Data Exchange (ETDEWEB)

    Bodenstein, G.W.; Bonczek, R.R.; Early, T.O.; Hale, T.B.; Huff, D.D.; Nickelson, M.D.; Rightmire, C.T.

    1992-11-01

    This report contains the evaluation and recommendations of a Groundwater Corrective Actions Review Team. The primary goal is to evaluate the technical merit of and the need to implement a proposed groundwater pump-and-treat demonstration project for the Northwest contaminant plume at Paducah, Kentucky. A key distinction recognized by the review team is that the proposed project is intended to be a full-scale hydraulic containment of contaminants migrating from the sources of the plume, not plume remediation. The key questions incorporated into this plan are whether (1) dense, nonaqueous-phase liquids (DNAPLS) are present in the Regional Gravel Aquifer (RGA) at the source of the plume and (2) [sup 99]Tc removal must be included as part of any groundwater treatment process. The first question cannot be answered until the contaminant sources are better defined; the second question requires further risk assessment and/or a policy decision by DOE. Technical evaluation by the review team suggests that the recommended course of action be to modify the proposed work plan to include accurate identification of the sources of contaminants and vertical distribution of contaminants within the Northwest plume before a decision is made on the preferred source-control option. If DNAPLs are not present in the RGA, removal or containment of the sources is recommended. If DNAPLs are present, then hydraulic containment will be required. Finally, the review team recognizes that it is necessary to initiate a more comprehensive analysis of sitewide remediation needs to create links between action taken for the Northwest plume and action taken for other contamination sites at PGPD.

  19. Reliability study: raw and make-up water system, Portsmouth Gaseous Diffusion Plant

    International Nuclear Information System (INIS)

    Peterman, S.M.; Wiehle, W.E.; Walder, A.; Houk, T.C.; West, R.M.

    1981-09-01

    A reliability study for determining the ability of the raw and make-up water system to provide reliable and adequate service through the year 2000 has been completed. This study includes an evaluation of the well fields, X-608 Raw Water Pump House, X-605 Booster Station Complex, X-611 Water Treatment Complex, and the associated piping. The raw and make-up water system is in good overall condition, but to maintain this condition, the reliability study team made the following recommendations: (1) increase well field capacity; (2) replace certain speed reducers at X-611; (3) repair deteriorated poles, crossarms, and accessories on F-2 and W-1 feeders; (4) stabilize the landslide in vicinity of the 48 in. raw water main; and (5) initiate further investigation, testing, or engineering studies to correct deficiencies in the supervisory control system between well fields, pump house, and X-611, and determine if the 2400 volt underground cables to X-608A wells should be replaced

  20. Using Artificial Neural Networks to Forecast Trichloroethylene Concentrations at the Paducah Gaseous Diffusion Plant

    Energy Technology Data Exchange (ETDEWEB)

    Kopp, Joshua D [Univ of KY, Dept of Civil Engineering

    2007-05-01

    To determine the future extent of the TCE contamination plume at PGDP, a groundwater and solute transport model has been developed by the Department of Energy (DOE). The model used to perform these calculations is MODFLOWT which is an enhanced groundwater transport model developed by the United States Geological Survey (USGS). MODFLOWT models groundwater movement as well as the transport of species that are subject to adsorption and decay by using a finite difference method (Duffield et al 2001). A significant limitation of MODFLOWT is that it requires large amounts of data. This data can be difficult and expensive to obtain. MODFLOWT also requires excessive computational time to perform one simulation. It is desirable to have a model that can predict the spatial extent of the contaminant plume without as much required data and that does not require excessive computational times. The purpose of this study is to develop and alternative model to MODFLOWT that can produce similar results for possible use in a companion management model. The alternative model used in this study is an artificial neural network (ANN).

  1. Report on the Biological Monitoring Program at Paducah Gaseous Diffusion Plant, January--December 1995

    International Nuclear Information System (INIS)

    Kszos, L.A.

    1996-04-01

    The BMP for PGDP consists of three major tasks: (1) effluent and ambient toxicity monitoring, (2) bioaccumulation studies, and (3) ecological surveys of stream communities (benthic macroinvertebrates, fish). This report focuses on ESD activities occurring from Jan. 1995 to Dec. 1995, although activities conducted outside this period are included as appropriate

  2. FACE: Free-Air CO[sub 2] Enrichment for plant research in the field

    Energy Technology Data Exchange (ETDEWEB)

    Hendrey, G.R. (ed.)

    1992-08-01

    Research programs concerning the effects of Carbon Dioxide(CO)[sub 2] on cotton plants are described. Biological responses studied include foliage response to CO[sub 2] fluctuations; yield of cotton exposed to CO[sub 2] enrichment; responses of photosynthesis and stomatal conductance to elevated CO[sub 2] in field-grown cotton; cotton leaf and boll temperatures; root response to CO[sub 2] enrichment; and evaluations of cotton response to CO[sub 2] enrichment with canopy reflectance observations.

  3. FACE: Free-Air CO{sub 2} Enrichment for plant research in the field

    Energy Technology Data Exchange (ETDEWEB)

    Hendrey, G.R. [ed.

    1992-08-01

    Research programs concerning the effects of Carbon Dioxide(CO){sub 2} on cotton plants are described. Biological responses studied include foliage response to CO{sub 2} fluctuations; yield of cotton exposed to CO{sub 2} enrichment; responses of photosynthesis and stomatal conductance to elevated CO{sub 2} in field-grown cotton; cotton leaf and boll temperatures; root response to CO{sub 2} enrichment; and evaluations of cotton response to CO{sub 2} enrichment with canopy reflectance observations.

  4. Uranium enrichment by laser: a technology for the future

    International Nuclear Information System (INIS)

    Cazalet, J.

    1999-01-01

    The SILVA (Isotopic Separation by Laser on atomic Vapor of uranium) process, developed by CEA and COGEMA, is an innovative system of production of enriched uranium, to be used as the fuel of nuclear reactors. It is a sound research program, calling on advanced technologies that are quickly changing. The goal is to cut drastically the production cost in comparison with the operating cost of the present plants based on gaseous diffusion. its industrialization is forecast for the beginning of next century. The SILVA process consists in putting a vapor of uranium through a beam of photons emitted by finely tuned lasers capable of ionising selectively the isotopes 235. The ionised isotopes are attracted on plates by an electric field, they are condensed and collected on these plates. The very high selectivity of enrichment technologies by laser, which are quite new, pave the way for compact and modular plants, which will consume little energy. Accordingly their production cost will be very low. So a new process could take a significant part of the uranium enrichment market after 2010. Even if the multinational EURODIF gaseous diffusion plant is modern and performing, it will be necessary to strengthen the French industry of uranium enrichment to maintain or improve its competitive position on the world market. This could be achieved by smoothly replacing EURODIF by a high performance laser plant. This is the common goal of CEA and COGEMA: all the efforts are concentrated on SILVA, the qualities of which (high selectivity, separation in one single step) have been demonstrated in the facilities of Saclay and Pierrelatte. 400 researchers and technicians are involved, as well as many industrial firms. The budget is equally by CEA and COGEMA through a cooperation agreement. The program includes: a phase of scientific and technical research, which has been highlighted in 1997-1998 by a demonstration of feasibility of the process; a phase of technological development, with

  5. UF/sub 6/ test loop for evaluation and implementation of international enrichment plant safeguards

    International Nuclear Information System (INIS)

    Cooley, J.N.; Fields, L.W.; Swindle, D.W. Jr.

    1987-01-01

    A functional test loop capable of simulating UF/sub 6/ flows, pressures, and pipe deposits characteristic of gas centrifuge enrichment plant piping has been designed and fabricated by the Enrichment Safeguards Program of Martin Marietta Energy Systems, Inc., for use by the International Atomic Energy Agency (IAEA) at its Safeguards Analytical Laboratory in Seibersdorf, Austria. The purpose of the test loop is twofold: (1) to enable the IAEA to evaluate and to calibrate enrichment safeguards measurement instrumentation to be used in limited frequency-unannounced access (LFUA) inspection strategy measurements at gas centrifuge enrichment plants and (2) to train IAEA inspectors in the use of such instrumentation. The test loop incorporates actual sections of cascade header pipes from the centrifuge enrichment plants subject to IAEA inspections. The test loop is described, applications for its use by the IAEA are detailed, and results from an initial demonstration session using the test loop are summarized. By giving the IAEA the in-house capability to evaluate LFUA inspection strategy approaches, to develop inspection procedures, to calibrate instrumentation, and to train inspectors, the UF/sub 6/ cascade header pipe test loop will contribute to the IAEA's success in implementing LFUA strategy inspections at gas centrifuge enrichment facilities subject to international safeguards inspections

  6. Distillation plant for tritium enrichment in metallic lithium

    International Nuclear Information System (INIS)

    Barnert, E.; Butzek, D.; Cordewiner, J.; Heinrichs, E.

    1984-06-01

    To close the external fuel cycle of fusion reactors, the tritium obtained from lithium must be separated off. One way of doing this is by high-temperature distillation and subsequent permeation. The construction of high-temperature distillation plant is described. For the time being, deuterium is processed instead of tritium. (orig.) [de

  7. Dispositions taken in France to limit gaseous releases from PWR power plants in abnormal operating conditions

    International Nuclear Information System (INIS)

    Collinet, J.; Guieu, S.; Mulcey, P.

    1989-12-01

    The implementation of France's major nuclear programme - 56 PWR units in service or under construction - has gone hand in hand with the development of an original philosophy in the field of nuclear safety. From an initial core of deterministic safety philosophy current in the seventies, which has been wholly retained and, in some instances, refined, a range of complements has been made to include consideration of a number of additional situations based on a probabilistic approach. This has resulted in a better coherence for safety and a reduction of the severe accident probability. Furthermore, the establishment of emergency plans has enabled the Safety Authorities and the utility to adopt a coherent and logical approach to severe accidents, with the aim of better achieving defence in depth. This has resulted in the provision of certain additional measures intended to further reduce the consequences of severe accidents. In a accordance with the safety philosophy, adopted in France for nuclear PWR power stations, filtration systems have been specified and installed to limit the radiological consequences of consecutive gaseous emissions, on the one hand, in accidents taken into account in the design and, on the other hand, in accidents liable to jeopardize the integrity of the containment

  8. A data transmission system for the centrifuge enrichment plant safeguards project

    International Nuclear Information System (INIS)

    Hesse, E.W.

    1987-04-01

    A novel data transmission system was developed to enable the Australian Safeguards Office (ASO) in Sydney to monitor remotely the running of an experimental enrichment facility at the Lucas Heights Reserch Laboratories, using Telecom telephone lines. The system allowed ASO to monitor the enrichment, flows and activity in sensitive areas of the plant by means of a master computer at ASO and a slave computer at Lucas Heights. The slave computer sent requested data and scanned video pictures to determine intrusive changes to the plant. Detailed descriptions of the transmission system and method of operation are given, together with an outline of experience obtained during a three-month surveillance of the facility

  9. Modeling of Diffusion of Plutonium in Other Metals and of Gaseous Species in Plutonium-Based Systems

    International Nuclear Information System (INIS)

    Cooper, Bernard R.; Gayanath W. Fernando; Beiden, S.; Setty, A.; Sevilla, E.H.

    2004-01-01

    Establish standards for temperature conditions under which plutonium, uranium, or neptunium from nuclear wastes permeates steel, with which it is in contact, by diffusion processes. The primary focus is on plutonium because of the greater difficulties created by the peculiarities of face-centered-cubic-stabilized (delta) plutonium (the form used in the technology generating the waste)

  10. Enrichment of {sup 15}N and {sup 10}B isotopes by chemical exchange process

    Energy Technology Data Exchange (ETDEWEB)

    D` Souza, A B; Sonwalkar, A S; Subrahmanyam, B V; Valladares, B A [Chemical Engineering Division, Bhabha Atomic Research Centre, Mumbai (India)

    1994-06-01

    Many processes are available for separation of stable isotopes like distillation, chemical exchange, thermal diffusion, gaseous diffusion, centrifuge etc. Chemical exchange process is eminently suitable for separation of isotopes of light elements. Work done on separation and enrichment of two of the stable isotopes viz. {sup 15}N and {sup 10}B in Chemical Engineering Division is presented. {sup 15}N is widely used as a tracer in agricultural research and {sup 10}B is used in nuclear industry as control rod material, soluble reactor poison, neutron detector etc. The work on {sup 15}N isotope resulted in a pilot plant, which was the only source of this material in the country for many years and later it was translated into a production plant as M/s. RCF Ltd. The work done on the ion-exchange process for enrichment of {sup 10}B isotope which is basically a chemical exchange process, is now being updated into a pilot plant to produce enriched {sup 10}B to be used as soluble reactor poison. (author). 5 refs., 2 figs., 3 tabs.

  11. Enrichment of 15N and 10B isotopes by chemical exchange process

    International Nuclear Information System (INIS)

    D'Souza, A.B.; Sonwalkar, A.S.; Subrahmanyam, B.V.; Valladares, B.A.

    1994-01-01

    Many processes are available for separation of stable isotopes like distillation, chemical exchange, thermal diffusion, gaseous diffusion, centrifuge etc. Chemical exchange process is eminently suitable for separation of isotopes of light elements. Work done on separation and enrichment of two of the stable isotopes viz. 15 N and 10 B in Chemical Engineering Division is presented. 15 N is widely used as a tracer in agricultural research and 10 B is used in nuclear industry as control rod material, soluble reactor poison, neutron detector etc. The work on 15 N isotope resulted in a pilot plant, which was the only source of this material in the country for many years and later it was translated into a production plant as M/s. RCF Ltd. The work done on the ion-exchange process for enrichment of 10 B isotope which is basically a chemical exchange process, is now being updated into a pilot plant to produce enriched 10 B to be used as soluble reactor poison. (author)

  12. Carbon isotope exchange between gaseous CO2 and thin solution films: Artificial cave experiments and a complete diffusion-reaction model

    Science.gov (United States)

    Hansen, Maximilian; Scholz, Denis; Froeschmann, Marie-Louise; Schöne, Bernd R.; Spötl, Christoph

    2017-08-01

    Speleothem stable carbon isotope (δ13C) records provide important paleoclimate and paleo-environmental information. However, the interpretation of these records in terms of past climate or environmental change remains challenging because of various processes affecting the δ13C signals. A process that has only been sparsely discussed so far is carbon isotope exchange between the gaseous CO2 of the cave atmosphere and the dissolved inorganic carbon (DIC) contained in the thin solution film on the speleothem, which may be particularly important for strongly ventilated caves. Here we present a novel, complete reaction diffusion model describing carbon isotope exchange between gaseous CO2 and the DIC in thin solution films. The model considers all parameters affecting carbon isotope exchange, such as diffusion into, out of and within the film, the chemical reactions occurring within the film as well as the dependence of diffusion and the reaction rates on isotopic mass and temperature. To verify the model, we conducted laboratory experiments under completely controlled, cave-analogue conditions at three different temperatures (10, 20, 30 °C). We exposed thin (≈0.1 mm) films of a NaHCO3 solution with four different concentrations (1, 2, 5 and 10 mmol/l, respectively) to a nitrogen atmosphere containing a specific amount of CO2 (1000 and 3000 ppmV). The experimentally observed temporal evolution of the pH and δ13C values of the DIC is in good agreement with the model predictions. The carbon isotope exchange times in our experiments range from ca. 200 to ca. 16,000 s and strongly depend on temperature, film thickness, atmospheric pCO2 and the concentration of DIC. For low pCO2 (between 500 and 1000 ppmV, as for strongly ventilated caves), our time constants are substantially lower than those derived in a previous study, suggesting a potentially stronger influence of carbon isotope exchange on speleothem δ13C values. However, this process should only have an

  13. Automated assay of uranium solution concentration and enrichment

    International Nuclear Information System (INIS)

    Horley, E.C.; Gainer, K.; Hansen, W.J.; Kelley, T.A.; Parker, J.L.; Sampson, T.E.; Walton, G.; Jones, S.A.

    1992-01-01

    For the first time, the concentration and enrichment of uranium solutions can be measured in one step. We have developed a new instrument to automatically measure the concentration and enrichment of uranium solutions through the adaptation of a commercial robot. Two identical solution enrichment systems are being installed in the Portsmouth Gaseous Diffusion Plant. These automated systems will reduce radiation exposure to personnel and increase the reliability and repeatability of the measurements. Each robotic system can process up to 40 batch and 8 priority samples in an unattended mode. Both passive gamma-ray and x-ray fluorescence (XRF) analyses are performed to determine total uranium concentration and 235 U enrichment. Coded samples are read by a bar-code reader to determine measurement requirements, then assayed by either or both of the gamma-ray and XRF instruments. The robot moves the sample containers and operates all shield doors and shutters, reducing hardware complexity. If the robots is out of service, an operator can manually perform all operations

  14. Phylogeny is a powerful tool for predicting plant biomass responses to nitrogen enrichment.

    Science.gov (United States)

    Wooliver, Rachel C; Marion, Zachary H; Peterson, Christopher R; Potts, Brad M; Senior, John K; Bailey, Joseph K; Schweitzer, Jennifer A

    2017-08-01

    Increasing rates of anthropogenic nitrogen (N) enrichment to soils often lead to the dominance of nitrophilic plant species and reduce plant diversity in natural ecosystems. Yet, we lack a framework to predict which species will be winners or losers in soil N enrichment scenarios, a framework that current literature suggests should integrate plant phylogeny, functional tradeoffs, and nutrient co-limitation. Using a controlled fertilization experiment, we quantified biomass responses to N enrichment for 23 forest tree species within the genus Eucalyptus that are native to Tasmania, Australia. Based on previous work with these species' responses to global change factors and theory on the evolution of plant resource-use strategies, we hypothesized that (1) growth responses to N enrichment are phylogenetically structured, (2) species with more resource-acquisitive functional traits have greater growth responses to N enrichment, and (3) phosphorus (P) limits growth responses to N enrichment differentially across species, wherein P enrichment increases growth responses to N enrichment more in some species than others. We built a hierarchical Bayesian model estimating effects of functional traits (specific leaf area, specific stem density, and specific root length) and P fertilization on species' biomass responses to N, which we then compared between lineages to determine whether phylogeny explains variation in responses to N. In concordance with literature on N limitation, a majority of species responded strongly and positively to N enrichment. Mean responses ranged three-fold, from 6.21 (E. pulchella) to 16.87 (E. delegatensis) percent increases in biomass per g N·m -2 ·yr -1 added. We identified a strong difference in responses to N between two phylogenetic lineages in the Eucalyptus subgenus Symphyomyrtus, suggesting that shared ancestry explains variation in N limitation. However, our model indicated that after controlling for phylogenetic non

  15. Aerodynamic isotope separation processes for uranium enrichment: process requirements

    International Nuclear Information System (INIS)

    Malling, G.F.; Von Halle, E.

    1976-01-01

    The pressing need for enriched uranium to fuel nuclear power reactors, requiring that as many as ten large uranium isotope separation plants be built during the next twenty years, has inspired an increase of interest in isotope separation processes for uranium enrichment. Aerodynamic isotope separation processes have been prominently mentioned along with the gas centrifuge process and the laser isotope separation methods as alternatives to the gaseous diffusion process, currently in use, for these future plants. Commonly included in the category of aerodynamic isotope separation processes are: (a) the separation nozzle process; (b) opposed gas jets; (c) the gas vortex; (d) the separation probes; (e) interacting molecular beams; (f) jet penetration processes; and (g) time of flight separation processes. A number of these aerodynamic isotope separation processes depend, as does the gas centrifuge process, on pressure diffusion associated with curved streamlines for the basic separation effect. Much can be deduced about the process characteristics and the economic potential of such processes from a simple and elementary process model. In particular, the benefit to be gained from a light carrier gas added to the uranium feed is clearly demonstrated. The model also illustrates the importance of transient effects in this class of processes

  16. Criteria for the safe storage of enriched uranium at the Y-12 Plant

    International Nuclear Information System (INIS)

    Cox, S.O.

    1995-07-01

    Uranium storage practices at US Department of Energy (DOE) facilities have evolved over a period spanning five decades of programmatic work in support of the nuclear deterrent mission. During this period, the Y-12 Plant in Oak Ridge, Tennessee has served as the principal enriched uranium facility for fabrication, chemical processing, metallurgical processing and storage. Recent curtailment of new nuclear weapons production and stockpile reduction has created significant amounts of enriched uranium available as a strategic resource which must be properly and safely stored. This standard specifies criteria associated with the safe storage of enriched uranium at the Y-12 Plant. Because programmatic needs, compliance regulations and desirable materials of construction change with time, it is recommended that these standards be reviewed and amended periodically to ensure that they continue to serve their intended purpose

  17. Description of the CNEA U308 powder production plant for low enrichment fuel plates

    International Nuclear Information System (INIS)

    Boero, N.L.; Celora, J.; Parodi, C.A.; Pertossi, F.R.; Marajofsky, A.

    1987-01-01

    The design of the 20% enriched U 3 O 8 powder production plant was based on laboratory level experiments. The UF 6 hydrolysis, ADU precipitation, U 3 O 8 conversion processes were used. The equipment, controls and confinement were set not only by the processes but also by safety requirements according to the kind and physical form of the uranium compounds in each stage and criticality considerations. This paper describes the installation, set up and operation of the plant during production. (Author)

  18. Socioeconomic effects of the DOE Gas Centrifuge Enrichment Plant. Volume 1: methodology and analysis

    International Nuclear Information System (INIS)

    1979-01-01

    The socioeconomic effects of the Gas Centrifuge Enrichment Plant being built in Portsmouth, Ohio were studied. Chapters are devoted to labor force, housing, population changes, economic impact, method for analysis of services, analysis of service impacts, schools, and local government finance

  19. Gaseous nebulae

    International Nuclear Information System (INIS)

    Williams, R.E.

    1976-01-01

    Gaseous nebulae are large, tenuous clouds of ionized gas that are associated with hot stars and that emit visible light because of the energy that they receive from the ultraviolet radiation of the stars. Examples include H II regions, planetary nebulae, and nova/supernova remnants. The emphasis is on the physical processes that occur in gaseous nebulae as opposed to a study of the objects themselves. The introduction discusses thermodynamic vs. steady-state equilibrium and excitation conditions in a dilute radiation field. Subsequent sections take up important atomic processes in gaseous nebulae (particle--particle collision rates, radiative interaction rates, cross sections), the ionization equilibrium (sizes of H II regions, ionization of the heavier elements), kinetic temperature and energy balance (heating of the electrons, cooling of the electrons), and the spectra of gaseous nebulae (line fluxes in nebulae). 7 figures, 5 tables

  20. Formation of the gaseous phase of impurity elements from coal combustion at a thermal power plant

    International Nuclear Information System (INIS)

    Kizil'shtein, L.Ya.; Levchenko, S.V.; Peretyakt'ko, A.G.

    1991-01-01

    Data are reported on the distribution of impurity elements in their principal carriers: organic matter, iron sulfides, and clays. Tests with high-temperature combustion of coals and argillites indicate that elements associated with clay minerals largely remain in ash and slag. They do not pass to the gas phase - a factor to be considered in assessment of environmental impact from thermal power plants and specification of toxic concentration levels of impurity elements in coal

  1. Characteristics of membranes which are suitable for isotopic separation by gaseous diffusion; Caracteristiques des barrieres utilisables pour la separation isotopique par diffusion gazeuse

    Energy Technology Data Exchange (ETDEWEB)

    Massignon, D [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    In this article we shall briefly describe how results obtained from the experimental analysis of the structure of membranes can be used on the one hand for determining this structure and on the other hand as a result for example of the detection of too many large pores or micro fissures and the existence of leaks at the joints, for eliminating membranes which can not be used industrially. Here we shall only consider the utilisation of information given by measurement of the specific permeability G{sub 0}, the pore radius for the molecular (diffusion) regime r{sub mol.}, the pore radius for the viscous diffusion regime the pore radius for the intermediate stage of diffusion, r{sub wicke}, the pore radius r{sub sep.} which is used for determining the actual separation, the distribution of the pore radius defined by mercury symmetry, the B.E.T. and central X ray diffusion. First of all we shall give the definition which is adopted in practice for these empirical values, which can be adapted for a rapid analysis of the quality of membranes by comparing them with the same measurements carried out on standard porous samples. In a second section we show in a few cases which have occurred in routine measurement how by comparison it is possible to eliminate membranes which do not have a suitable structure. (author) [French] Dans cet expose, nous allons montrer sommairement comment les resultats donnes par les methodes experimentales de controle de la structure des barrieres peuvent, d'une part, conduire a une certaine representation de cette structure et, d'autre part, permettre d'eliminer les barrieres non utilisables industriellement en detectant par exemple les trop nombreux gros pores ou microfissures et l'existence de fuites aux joints. Nous nous limiterons ici a l'exploitation des renseignements donnes par la permeabilite specifique G{sub 0}, le rayon de pore r{sub mol.} effectif en regime moleculaire, le rayon de pore r{sub visq.} effectif en regime visqueux, le

  2. 10 CFR Appendix B to Part 110 - Illustrative List of Gas Centrifuge Enrichment Plant Components Under NRC's Export Licensing...

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Illustrative List of Gas Centrifuge Enrichment Plant... 110—Illustrative List of Gas Centrifuge Enrichment Plant Components Under NRC's Export Licensing Authority 1. Assemblies and components especially designed or prepared for use in gas centrifuges. Note: The...

  3. Isotope enrichment

    International Nuclear Information System (INIS)

    Lydtin, H-J.; Wilden, R.J.; Severin, P.J.W.

    1978-01-01

    The isotope enrichment method described is based on the recognition that, owing to mass diffusion and thermal diffusion in the conversion of substances at a heated substrate while depositing an element or compound onto the substrate, enrichment of the element, or a compound of the element, with a lighter isotope will occur. The cycle is repeated for as many times as is necessary to obtain the degree of enrichment required

  4. Gaseous release of radioactive iodine from decaying plants. I. Release following foliar and root uptake

    International Nuclear Information System (INIS)

    Saas, Arsene; Grauby, Andre

    1975-12-01

    Iodine uptake by plants is a significant link in the contamination of the food chain. Long half-live iodine was studied considering foliar and root uptake, loss by rain scavenging, residue decay or outgassing in order to assess two aspects of the problem: the importance of outgassing and the effect of the route of transfer on iodine losses. It appeared that iodine release was a function of the vegetal type, there were differences according to the pattern of absorption (via leaf or root) and the processes of iodine release were usually related to biochemical mechanisms [fr

  5. Enrichment of Cs-137 in some wild plants and determination of the transfer factors

    International Nuclear Information System (INIS)

    Molzahn, D.

    1993-01-01

    As a consequence of the nuclear weapons tests and the accident in the Chernobyl nuclear power plant some wild plants exhibit a relatively high enrichment in Cs-137. The examples cited here include heather, forest grown grass, ferns, needles and cones of spruces and firs and, obviously, also some species of mushrooms. While the transfer factors of cultivated plants range from 0.001 to 0.1 according to the literature and measurements of our own, values from 1 to 38 have been measured for heather, depending on the nature of the soil. One of the consequences of this relatively high enrichment is the enhanced cesium content in honeys produced from heather. It is intended to continue the relevant measurements in 1993. (orig.) [de

  6. Time-independent hybrid enrichment for finite element solution of transient conduction–radiation in diffusive grey media

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, M. Shadi, E-mail: m.s.mohamed@durham.ac.uk [School of Engineering and Computing Sciences, University of Durham, South Road, Durham DH1 3LE (United Kingdom); Seaid, Mohammed; Trevelyan, Jon [School of Engineering and Computing Sciences, University of Durham, South Road, Durham DH1 3LE (United Kingdom); Laghrouche, Omar [Institute for Infrastructure and Environment, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)

    2013-10-15

    We investigate the effectiveness of the partition-of-unity finite element method for transient conduction–radiation problems in diffusive grey media. The governing equations consist of a semi-linear transient heat equation for the temperature field and a stationary diffusion approximation to the radiation in grey media. The coupled equations are integrated in time using a semi-implicit method in the finite element framework. We show that for the considered problems, a combination of hyperbolic and exponential enrichment functions based on an approximation of the boundary layer leads to improved accuracy compared to the conventional finite element method. It is illustrated that this approach can be more efficient than using h adaptivity to increase the accuracy of the finite element method near the boundary walls. The performance of the proposed partition-of-unity method is analyzed on several test examples for transient conduction–radiation problems in two space dimensions.

  7. Salicylic acid confers salt tolerance in potato plants by improving water relations, gaseous exchange, antioxidant activities and osmoregulation.

    Science.gov (United States)

    Faried, Hafiz Nazar; Ayyub, Chaudhary Muhammad; Amjad, Muhammad; Ahmed, Rashid; Wattoo, Fahad Masoud; Butt, Madiha; Bashir, Mohsin; Shaheen, Muhammad Rashid; Waqas, Muhammad Ahmed

    2017-04-01

    Potato is an important vegetable; however, salt stress drastically affects its growth and yield. A pot experiment was therefore conducted to assess salicylic acid efficacy in improving performance of potato cultivars, grown under salt stress (50 mmol L -1 ). Salicylic acid at 0.5 mmol L -1 was sprayed on to potato plants after 1 week of salinity application. Salt stress effects were ameliorated by salicylic acid effectively in both the studied cultivars. N-Y LARA proved more responsive to salicylic acid application than 720-110 NARC, which confirmed genetic variation between cultivars. Salicylic acid scavenged reactive oxygen species by improving antioxidant enzyme activities (superoxide dismutase, catalase, peroxidases) and regulating osmotic adjustment (proline, phenolic contents), which led to enhanced water relation and gaseous exchange attributes, and thereby increased potassium availability and reduced sodium content in potato leaves. Moreover, potato tuber yield showed a positive correlation with potassium content, photosynthesis and antioxidant enzyme activities. Salt tolerance efficacy of salicylic acid is authenticated in improving potato crop performance under salt stress. Salicylic acid effect was more pronounced in N-Y LARA, reflecting greater tolerance than 720-110 NARC, which was confirmed as a susceptible cultivar. Hence salicylic acid at 0.5 mmol L -1 and cultivation of N-Y LARA may be recommended in saline soil. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  8. Preliminary analysis of 500 MWt MHD power plant with oxygen enrichment

    Science.gov (United States)

    1980-04-01

    An MHD Engineering Test Facility design concept is analyzed. A 500 MWt oxygen enriched MHD topping cycle integrated for combined cycle operation with a 400 MWe steam plant is evaluated. The MHD cycle uses Montana Rosebud coal and air enriched to 35 mole percent oxygen preheated to 1100 F. The steam plant is a 2535 psia/1000 F/1000 F reheat recycle that was scaled down from the Gilbert/Commonwealth Reference Fossil Plant design series. Integration is accomplished by blending the steam generated in the MHD heat recovery system with steam generated by the partial firing of the steam plant boiler to provide the total flow requirement of the turbine. The major MHD and steam plant auxiliaries are driven by steam turbines. When the MHD cycle is taken out of service, the steam plant is capable of stand-alone operation at turbine design throttle flow. This operation requires the full firing of the steam plant boiler. A preliminary feasibility assessment is given, and results on the system thermodynamics, construction scheduling, and capital costs are presented.

  9. Application of ICPMS for performance evaluation of boron enrichment plant at HWP, Manuguru

    International Nuclear Information System (INIS)

    Murthy, P.K.; Mohapatra, C.; Vithal, G.K.

    2011-01-01

    10 B enriched compounds are used in neutron control rod in Fast Breeder Reactors (FBR), Neutron Detector, Neutron Capture Therapy, and Neutron Shielding. Heavy Water Board (HWB) is given a mandate to produce enriched elemental boron which is being produced using Ion exchange chromatography and BF 3 - ether complex distillation methods. Ion Exchange Chromatography based Boron Enrichment Plant is operating at HWP, Manuguru. Ion Exchange Chromatography based process depends, besides other process parameters, on column run time and movement of band length. For effective process and quality control, it is necessary to analyze 10 B/ 11 B ratio in feed, process stream, waste and the product. 10 B/ 11 B ratio measurements are possible by Thermal Ionization Mass Spectrometer (TIMS) and Inductively Coupled Plasma Mass Spectrometer (ICPMS), the former offers better accuracy but takes longer analysis time whereas the later offers quick analysis of isotopic ratios and as well as trace metal impurities in the Boric acid

  10. Fiscal year 1986 Department of Energy Authorization (uranium enrichment and electric energy systems, energy storage and small-scale hydropower programs). Volume VI. Hearings before the Subcommittee on Energy Research and Production of the Committee on Science and Technology, US House of Representatives, Ninety-Ninth Congress, First Session, February 28; March 5, 7, 1985

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    Volume VI of the hearing record covers three days of testimony on the future of US uranium enrichment and on programs involving electric power and energy storage. There were four areas of concern about uranium enrichment: the choice between atomic vapor laser isotope separation (AVLIS) and the advanced gas centrifuge (AGC) technologies, cost-effective operation of gaseous diffusion plants, plans for a gas centrifuge enrichment plant, and how the DOE will make its decision. The witnesses represented major government contractors, research laboratories, and energy suppliers. The discussion on the third day focused on the impact of reductions in funding for electric energy systems and energy storage and a small budget increase to encourage small hydropower technology transfer to the private sector. Two appendices with additional statements and correspondence follow the testimony of 17 witnesses

  11. Development and technical implementation of the separation nozzle process for enrichment of uranium 235

    International Nuclear Information System (INIS)

    Syllus Martins Pinto, C.; Voelcker, H.; Becker, E.W.

    1977-12-01

    The separation nozzle process for the enrichment of uranium-235 has been developed at the Karlsruhe Nuclear Research Center as an alternative to the gaseous diffusion and centrifuge process. The separation of uranium isotopes is achieved by the deflection of a jet of uranium hexafluoride mixed with hydrogen. Since 1970, the German company of STEAG, has been involved in the technological development and commercial implementation of the nozzle process. In 1975, the Brazilian company of NUCLEBRAS, and the German company of Interatom, joined the effort. The primary objective of the common activity is the construction of a separation nozzle demonstration plant with an annual capacity of about 200 000 SWU and the development of components of a commercial plant. The paper covers the most important steps in the development and the technical implementation of the process. (orig.) [de

  12. Deposition velocity of gaseous organic iodine from the atmosphere to rice plants

    International Nuclear Information System (INIS)

    Muramatsu, Yasuyuki; Shigeo-Uchida; Sumiya, Misako; Ohmomo, Yoichiro

    1996-01-01

    To obtain parameter values for the assessment of 129 I transfer from the atmosphere to rice, deposition of CH 3 I to rice plants has been studied. The mass normalized deposition velocity (V D ) of CH 3 I for rough (unhulled) rice was 0.00048 cm 3 g -1 s -1 , which is about 1/300 of that of I 2 . Translocation of iodine, deposited as CH 3 I on leaves and stems, to rice grain was negligibly small. Distribution of iodine between hull and inner part of the grain was found to depend also on the chemical forms of atmospheric iodine to be deposited. The ratio of the iodine distribution in a grain exposed to CH 3 I was as follows: rough rice: brown rice (hulled rice):polished rice = 1.0:0.49:0.38. The distribution ratio in polished grains for CH 3 I exposed rice was about 20 times higher than that for I 2 . 22 refs., 1 fig., 6 tabs

  13. Gas centrifuge enrichment plants inspection frequency and remote monitoring issues for advanced safeguards implementation

    International Nuclear Information System (INIS)

    Boyer, Brian David; Erpenbeck, Heather H.; Miller, Karen A.; Ianakiev, Kiril D.; Reimold, Benjamin A.; Ward, Steven L.; Howell, John

    2010-01-01

    Current safeguards approaches used by the IAEA at gas centrifuge enrichment plants (GCEPs) need enhancement in order to verify declared low enriched uranium (LEU) production, detect undeclared LEU production and detect high enriched uranium (BEU) production with adequate probability using non destructive assay (NDA) techniques. At present inspectors use attended systems, systems needing the presence of an inspector for operation, during inspections to verify the mass and 235 U enrichment of declared cylinders of uranium hexafluoride that are used in the process of enrichment at GCEPs. This paper contains an analysis of how possible improvements in unattended and attended NDA systems including process monitoring and possible on-site destructive analysis (DA) of samples could reduce the uncertainty of the inspector's measurements providing more effective and efficient IAEA GCEPs safeguards. We have also studied a few advanced safeguards systems that could be assembled for unattended operation and the level of performance needed from these systems to provide more effective safeguards. The analysis also considers how short notice random inspections, unannounced inspections (UIs), and the concept of information-driven inspections can affect probability of detection of the diversion of nuclear material when coupled to new GCEPs safeguards regimes augmented with unattended systems. We also explore the effects of system failures and operator tampering on meeting safeguards goals for quantity and timeliness and the measures needed to recover from such failures and anomalies.

  14. Gaseous Matter

    CERN Document Server

    Angelo, Joseph A

    2011-01-01

    aseous Matter focuses on the many important discoveries that led to the scientific interpretation of matter in the gaseous state. This new, full-color resource describes the basic characteristics and properties of several important gases, including air, hydrogen, helium, oxygen, and nitrogen. The nature and scope of the science of fluids is discussed in great detail, highlighting the most important scientific principles upon which the field is based. Chapters include:. Gaseous Matter An Initial Perspective. Physical Characteristics of Gases. The Rise of the Science of Gases. Kinetic Theory of

  15. Development of IAEA safeguards at low enrichment uranium fuel fabrication plants

    International Nuclear Information System (INIS)

    Badawy, I.

    1988-01-01

    In this report the nuclear material at low enrichment uranium fuel fabrication plants under IAEA safeguards is studied. The current verification practices of the nuclear material and future improvements are also considered. The problems met during the implementation of the the verification measures of the nuclear material - particularly for the fuel assemblies are discussed. The additional verification activities as proposed for future improvements are also discussed including the physical inventory verification and the verification of receipts and shipments. It is concluded that the future development of the present IAEA verification practices at low enrichment uranium fuel fabrication plants would necessitate the application of quantitative measures of the nuclear material and the implementation of advanced measurement techniques and instruments. 2 fig., 4 tab

  16. Integrated Information Technology Framework for Analysis of Data from Enrichment Plants to Support the Safeguards Mission

    International Nuclear Information System (INIS)

    Marr, Clifton T.; Thurman, David A.; Jorgensen, Bruce V.

    2008-01-01

    Many examples of software architectures exist that support process monitoring and analysis applications which could be applied to enrichment plants in a fashion that supports the Safeguards Mission. Pacific Northwest National Laboratory (PNNL) has developed mature solutions that will provide the framework to support online statistical analysis of enrichment plans and the entire nuclear fuel cycle. Most recently, PNNL has developed a refined architecture and supporting tools that address many of the common problems analysis and modeling environments experience: pipelining, handling large data volumes, and real-time performance. We propose the architecture and tools may be successfully used in furthering the goals of nuclear material control and accountability as both an aid to processing plant owners and as comprehensive monitoring for oversight teams.

  17. Digital simulation of an enrichment process for solutions by means of an advection-diffusion chamber

    International Nuclear Information System (INIS)

    Artucio, G.; Suarez, R.; Uruguay Catholic University)

    1995-01-01

    An ab-initio digital simulation of the space-time dynamics of the concentration field of a solute in an advection-diffusion chamber is done. Some questions related to the digital simulation of the concentration field using the analytical solution obtained in a previous paper are discussed

  18. Development of a computer systems for operational data acquisition of uranium isotopic enrichment pilot plant

    International Nuclear Information System (INIS)

    Maia, W.M.C.

    1985-01-01

    A pilot plant for uranium enrichment using the jet nozzle process was transfered from Federal Republic of Germany to Brazil, to train Brazilian technicist in its operation and to improve the process. This pilot plant is monitored by a data acquisition system and the possibility of faulty events would cause serious dificulties, as far as maintenance is concerned (for instance, unvailable special components). It is described the development of a new system, which is proposed in order to minimize difficulties with maintenance that utilizes in the assembling integrated circuits of large scale of integration. It is controlled by a microcomputer. (Author) [pt

  19. Effect of strain rate on sooting limits in counterflow diffusion flames of gaseous hydrocarbon fuels: Sooting temperature index and sooting sensitivity index

    KAUST Repository

    Wang, Yu

    2014-05-01

    The effect of the strain rate on the sooting limits in counterflow diffusion flames was investigated in various gaseous hydrocarbon fuels by varying the nitrogen dilution in the fuel and oxidizer streams. The sooting limit was defined as the critical fuel and oxygen mole fraction at which soot started to appear in the elastic light scattering signal. The sooting region for normal alkane fuels at a specified strain rate, in terms of the fuel and oxygen mole fraction, expanded as the number of carbon atoms increased. The alkene fuels (ethylene, propene) tested had a higher propensity for sooting as compared with alkane fuels with the same carbon numbers (ethane, propane). Branched iso-butane had a higher propensity for sooting than did n-butane. An increase in the strain rate reduced the tendency for sooting in all the fuels tested. The sensitivity of the sooting limit to the strain rate was more pronounced for less sooting fuels. When plotted in terms of calculated flame temperature, the critical oxygen mole fraction exhibited an Arrhenius form under sooting limit conditions, which can be utilized to significantly reduce the effort required to determine sooting limits at different strain rates. We found that the limiting temperatures of soot formation flames are viable sooting metrics for quantitatively rating the sooting tendency of various fuels, based on comparisons with threshold soot index and normalized smoke point data. We also introduce a sooting temperature index and a sooting sensitivity index, two quantitative measures to describe sooting propensity and its dependence on strain rate. © 2013 The Combustion Institute.

  20. Air strikes on uranium enrichment plants as potential sources of radioecological danger

    Directory of Open Access Journals (Sweden)

    Živanov Dragan

    2007-01-01

    Full Text Available According to the Non Proliferation Treaty (NPT, the signatory countries are not forbidden to preform uranium enrichment for peaceful purposes. However, if there is a justified doubt that the uranium enrichment is performed with the aim to produce nuclear weapons, this certainly causes great concern. In this case, the international community can apply pressure to a certain country if it determines that the country does not want to cease activities of making its own nuclear weapons. The international community pressure on the country can be intesified until its political leadership is not made to question and cease all activities of producing nuclear weapons. This pressure can be political, economic, and as a last resort-military. As a gesture of goodwill the country can stop the uranium enrichment process. In this way, the country shows that it finally gives up the intention to produce nuclear weapons. However, when military pressure is applied, i.e. military strikes (air strikes for example on nuclear plants used for uranium enrichment, this certainly creates a risk of releasing radioactivity into the environment. That is why the aim of this paper is to signal this very fact. Using military force in these cases leads to additional radioactive contamination of the environment, so this way of solving conflicts should be avoided within the international community.

  1. Irradiation program of slightly enriched fuel elements at the Atucha I nuclear power plant

    International Nuclear Information System (INIS)

    Casario, J.A.; Cesario, R.H.; Perez, R.A.; Sidelnik, J.I.

    1987-01-01

    An irradiation program of fuel elements with slightly enriched uranium is implemented, tending to the homogenization of core at Atucha I nuclear power plant. The main benefits of the enrichment program are: a) to extend the average discharge burnup of fuel elements, reducing the number of elements used to generate the same amount of energy. This implies a smaller annual consumption of elements and consequently the reduction of transport and replacement operations and of the storage pool systems as well as that of radioactive wastes; b) the saving of uranium and structural materials (Zircaloy and others). In the initial stage of program an homogeneous core enrichment of 0.85% by weight of U-235 is anticipated. The average discharge burnup of fuel elements, as estimated by previous studies, is approximately 11.6 MW d/kg U. The annual consumption of fuel elements is reduced from 396 of natural uranium to 205, with a load factor of 0.85. It is intended to reach the next equilibrium steps with an enrichment of 1.00 and 1.20% in U-235. (Author)

  2. Enrichment of Gamma-Aminobutyric Acid in Bean Sprouts: Exploring Biosynthesis of Plant Metabolite Using Common Household Reagents

    Science.gov (United States)

    Rojanarata, Theerasak; Plianwong, Samarwadee; Opanasopit, Praneet; Ngawhirunpat, Tanasait

    2018-01-01

    The enrichment of plant foods with gamma-aminobutyric acid (GABA) is currently an interesting issue in the field of nutraceuticals and can be used as an experiment for upper-division undergraduate students. Here, an interdisciplinary hands-on experiment to produce GABA-enriched mung bean sprouts using common household reagents is described. Based…

  3. RADIO FREQUENCY IDENTIFICATION DEVICES: EFFECTIVENESS IN IMPROVING SAFEGUARDS AT GAS-CENTRIFUGE URANIUM-ENRICHMENT PLANTS

    International Nuclear Information System (INIS)

    JOE, J.

    2007-01-01

    Recent advances in radio frequency identification devices (RFIDs) have engendered a growing interest among international safeguards experts. Potentially, RFIDs could reduce inspection work, viz. the number of inspections, number of samples, and duration of the visits, and thus improve the efficiency and effectiveness of international safeguards. This study systematically examined the applications of RFIDs for IAEA safeguards at large gas-centrifuge enrichment plants (GCEPs). These analyses are expected to help identify the requirements and desirable properties for RFIDs, to provide insights into which vulnerabilities matter most, and help formulate the required assurance tests. This work, specifically assesses the application of RFIDs for the ''Option 4'' safeguards approach, proposed by Bruce Moran, U. S. Nuclear Regulatory Commission (NRC), for large gas-centrifuge uranium-enrichment plants. The features of ''Option 4'' safeguards include placing RFIDs on all feed, product and tails (F/P/T) cylinders, along with WID readers in all FP/T stations and accountability scales. Other features of Moran's ''Option 4'' are Mailbox declarations, monitoring of load-cell-based weighing systems at the F/P/T stations and accountability scales, and continuous enrichment monitors. Relevant diversion paths were explored to evaluate how RFIDs improve the efficiency and effectiveness of safeguards. Additionally, the analysis addresses the use of RFIDs in conjunction with video monitoring and neutron detectors in a perimeter-monitoring approach to show that RFIDs can help to detect unidentified cylinders

  4. Application of a method to measure uranium enrichment without use of standards

    International Nuclear Information System (INIS)

    Saule, F.A.; Righetti, M.A.

    1998-01-01

    Full text: The determination of uranium enrichment in the many different stages present at a gaseous diffusion enrichment plant (diffusers, cisterns, deposits in pipes, drums with rests of process), or materials of deposit (plates of fuel elements not irradiated and recipients with uranium oxide), that have several geometries and physics properties of the containers, is very important for safeguards inspections. In this work is tested a non destructive analysis technique to determine the value of uranium enrichment of different samples with uranium materials without use of standards, to apply in safeguards inspections. It was used a hyper pure germanium detector with efficiency of 20% to obtain the gamma spectrum of the samples. In each spectrum, were used the net area values corresponding to four lines of U-235 (at 143, 163, 186 and 205 keV) and three lines of U-238 (258, 766 and 1001 keV); these values were analysed with two different methods. The comparison of the calculated and declared values showed a discrepancy of about 10%. (author) [es

  5. Influence of sediment organic enrichment and water alkalinity on growth of aquatic isoetid and elodeid plants

    DEFF Research Database (Denmark)

    Raun, Ane-Marie Løvendahl; Borum, Jens; Jensen, Kaj Sand

    2010-01-01

    1. Lake eutrophication has increased phytoplankton blooms and sediment organic matter. Among higher plants, small, oligotrophic rosette species (isoetids) have disappeared, while a few tall, eutrophic species (elodeids) may have persisted. Despite recent reduction of nutrient loading in restored...... lakes, the vegetation has rarely regained its former composition and coverage. Patterns of recovery may depend on local alkalinity because HCO3- stimulates photosynthesis of elodeids and not of isoetids. In laboratory growth experiments with two isoetids (Lobelia dortmanna and Littorella uniflora......) and two elodeids (Potamogeton crispus and P. perfoliatus), we test whether organic enrichment of lake sediments has a long-lasting influence by: (i) reducing plant growth because of oxygen stress on plant roots and (ii) inhibiting growth more for isoetids than elodeids. We also test whether (iii...

  6. Subtle Gardeners: Inland Predators Enrich Local Topsoils and Enhance Plant Growth.

    Science.gov (United States)

    Fedriani, José M; Garrote, Pedro José; Delgado, María del Mar; Penteriani, Vincenzo

    2015-01-01

    Inland vertebrate predators could enrich of nutrients the local top soils in the area surrounding their nests and dens by depositing faeces, urine, and prey remains and, thus, alter the dynamics of plant populations. Surprisingly, and in contrast with convincing evidence from coastal habitats, whether and how this phenomenon occurs in inland habitats is largely uncertain even though these habitats represent a major fraction of the earth's surface. We investigated during two consecutive breeding seasons the potential enrichment of the top-soils associated with inland ground-nesting eagle owls Bubo bubo, as well as its possible consequences in the growth of two common annual grasses in southern Spain. Top-soils associated with owl nests differed strongly and significantly from control top-soils in chemical parameters, mainly fertility-related properties. Specifically, levels of available phosphorus, total nitrogen, organic matter, and available potassium were 49.1, 5.6, 3.1, and 2.7 times higher, respectively, in top-soils associated with owl nests as compared to control top-soils. Germination experiments in chambers indicated that nutrient enrichment by nesting owls enhanced seedling growth in both annual grasses (Phalaris canariensis and Avena sativa), with seedling size being 1.4-1.3 times higher in owl nest top-soils than in control top-soils. Our experimental study revealed that pervasive inland, predatory birds can profoundly enrich the topsoil around their nests and, thus, potentially enhance local vegetation growth. Because diverse inland vertebrate predators are widespread in most habitats they have a strong potential to enhance spatial heterogeneity, impinge on plant communities, and exert an overlooked effect on primary productivity worldwide.

  7. Subtle Gardeners: Inland Predators Enrich Local Topsoils and Enhance Plant Growth.

    Directory of Open Access Journals (Sweden)

    José M Fedriani

    Full Text Available Inland vertebrate predators could enrich of nutrients the local top soils in the area surrounding their nests and dens by depositing faeces, urine, and prey remains and, thus, alter the dynamics of plant populations. Surprisingly, and in contrast with convincing evidence from coastal habitats, whether and how this phenomenon occurs in inland habitats is largely uncertain even though these habitats represent a major fraction of the earth's surface. We investigated during two consecutive breeding seasons the potential enrichment of the top-soils associated with inland ground-nesting eagle owls Bubo bubo, as well as its possible consequences in the growth of two common annual grasses in southern Spain. Top-soils associated with owl nests differed strongly and significantly from control top-soils in chemical parameters, mainly fertility-related properties. Specifically, levels of available phosphorus, total nitrogen, organic matter, and available potassium were 49.1, 5.6, 3.1, and 2.7 times higher, respectively, in top-soils associated with owl nests as compared to control top-soils. Germination experiments in chambers indicated that nutrient enrichment by nesting owls enhanced seedling growth in both annual grasses (Phalaris canariensis and Avena sativa, with seedling size being 1.4-1.3 times higher in owl nest top-soils than in control top-soils. Our experimental study revealed that pervasive inland, predatory birds can profoundly enrich the topsoil around their nests and, thus, potentially enhance local vegetation growth. Because diverse inland vertebrate predators are widespread in most habitats they have a strong potential to enhance spatial heterogeneity, impinge on plant communities, and exert an overlooked effect on primary productivity worldwide.

  8. Theory of the separation of a gaseous mixture by diffusion through a porous wall (1962); Theorie de la separation d'un melange gazeux par diffusion a travers une paroi poreuse (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Breton, J P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-06-15

    The present-day theories of separation by gaseous diffusion (Present and de BETHUNE, KYNCH, BOSANQUET) are all based on the same model in which the pores are cylindrical capillaries. In the theory presented here, we substitute for this model that of a disordered and isotropic bed of identical spheres, which describes more accurately most of the porous media. We take as our starting point DERIAGUINE and BAKANOV'S permeability theory, which expresses the flow of a simple gas in such a bed when the latter is of high porosity. We first generalise this theory in the case of medium and low porosities; then, we go on to a mixture of two gases, from which we deduce our separation theory. Finally we compare our results with those of Present and de BETHUNE. (author) [French] Les theories actuelles de la separation par diffusion gazeuse (PRESENT et de BETHUNE, KYNCH, BOSANQUET) reposent toutes sur le modele des pores capillaires cylindriques. Dans la theorie presentee ici, nous substituons a ce modele celui d'un empilement desordonne et isotropes de spheres identiques, qui decrit plus correctement la plupart des milieux poreux. Nous partons de la theorie de la permeabilite de DERIAGUINE et BAKANOV, qui exprime l'ecoulement d'un gaz simple dans un tel empilement dans le cas ou la porosite en est elevee. Nous generalisons d'abord cette theorie du cas des porosites moyennes ou faibles, puis, passant a un melange de deux gaz, nous en deduisons une theorie de la separation. Pour terminer, nous comparons nos resultats a ceux de PRESENT et de BETHUNE. (auteur)

  9. Network diffusion-based analysis of high-throughput data for the detection of differentially enriched modules

    Science.gov (United States)

    Bersanelli, Matteo; Mosca, Ettore; Remondini, Daniel; Castellani, Gastone; Milanesi, Luciano

    2016-01-01

    A relation exists between network proximity of molecular entities in interaction networks, functional similarity and association with diseases. The identification of network regions associated with biological functions and pathologies is a major goal in systems biology. We describe a network diffusion-based pipeline for the interpretation of different types of omics in the context of molecular interaction networks. We introduce the network smoothing index, a network-based quantity that allows to jointly quantify the amount of omics information in genes and in their network neighbourhood, using network diffusion to define network proximity. The approach is applicable to both descriptive and inferential statistics calculated on omics data. We also show that network resampling, applied to gene lists ranked by quantities derived from the network smoothing index, indicates the presence of significantly connected genes. As a proof of principle, we identified gene modules enriched in somatic mutations and transcriptional variations observed in samples of prostate adenocarcinoma (PRAD). In line with the local hypothesis, network smoothing index and network resampling underlined the existence of a connected component of genes harbouring molecular alterations in PRAD. PMID:27731320

  10. Development and industrial application of gas centrifuges to uranium enrichment in the USSR

    International Nuclear Information System (INIS)

    Abbakumov, E.I.; Bazhenov, V.A.; Verbin, Yu.V.

    1989-01-01

    Review of state and studies in the field of gaseous diffusion technology and centrifugal method of uranium enrichment in the USSR is given. Domestic industrial gas centrifuges, forming to-day the main part of separation capacities in the USSR, are noted for low specific energy consumption and high reliability. Centrifugal technology in the USSR is applied both to uranium enrichment (including one for export) and to separation of isotopes of other chemical elements

  11. Italian activities in the field of uranium enrichment

    International Nuclear Information System (INIS)

    Bullio, P.

    1977-01-01

    The Italian effort on uranium enrichment is principally developed along the two classical processes: gaseous diffusion, centrifuges. Research, development and industrial activities play different role in the two methods; a special working group (GIAU) was established by CNEN to help coordinating this activity. In the field of gaseous diffusion, research and development effort, was, from the starting of the program in 1968, mainly devoted to barriers and compressors. The aim was to gain a full understanding of the process and to demonstrate the capability to overcome the main problems of this technology. Isotope separation of UF 6 was demonstrated in 1974 at an experimental plant level. Cost sharing contracts were signed between CNEN and industries to build prototypes and ''first of a kind'' components; small production lines have been set up to evaluate economics and assess production quality: Eurodif is partially associated with the development of this activity. On the industrial level Agip Nucleare and CNEN were among the promoters of the Eurodif venture from the beginning in 1973 and now own 25% of the shares. In the field of ultracentrifugation the work is still devoted mainly to research and development on the machines. The demonstration of the separation process has been achieved in 1973 at laboratory level with a Zippe type centrifuge. Further on, work has been aimed to the development of high capacity machines and different solutions are under close scrutiny. Carbon fibers and multiple rotors machines have been mechanically tested; the first reference design of small cascade plant has been completed. In the field of laser separation, after a complete and critical survey of different process under development abroad, experimental research work is now being undertaken; experiments on basic aspects of the process are in progress [fr

  12. Development of simulator for the uranium enrichment plant using a real-time expert system

    International Nuclear Information System (INIS)

    Kodama, Shinichi; Kondo, Kazuhiro.

    1996-01-01

    The uranium enrichment plant simulator of the new material centrifuge cascade for intelligent process monitoring and alarm generation has been developed by applying an artificial intelligence technology. The real time expert shell, G2 has been used for the system development. The UF6 supply system and cascade equipment was modeled using G2. For a detailed calculation of the cascade, the cascade static characteristic FORTRAN program has been used. These calculation results have been used for the diagnosis of a suspicious behavior in measurement data. Especially, when the deviation of the product uranium concentration was detected, the cause of the deviation was inferred from the knowledge base. (author)

  13. Computational fluid mechanics in R and D on uranium enrichment

    International Nuclear Information System (INIS)

    Soubbaramayer, O.

    1988-01-01

    Uranium enrichment represents an essential link in the cycle of nuclear fuels for power production. There are many processes of uranium enrichment, but three of them dominate the nuclear history as well in the past (Gaseous diffusion and centrifugation) as in the present (Laser process). The important role played by the Numerical Fluid Mechanics in the three processes is pointed out. The type of problem raised by Gaseous Diffusion is Channel Flow with wall suction, by Centrifugation, flow of a Compressible gas in a strongly rotating cylinder (Stewartson and Ekman layers) and by Laser process, Thermocapillary-buoyancy flow of a molten metal in an evaporation crucible. The methods and results in these problems are reviewed. 18 refs, 11 figs

  14. Teasing apart plant community responses to N enrichment: the roles of resource limitation, competition and soil microbes.

    Science.gov (United States)

    Farrer, Emily C; Suding, Katharine N

    2016-10-01

    Although ecologists have documented the effects of nitrogen enrichment on productivity, diversity and species composition, we know little about the relative importance of the mechanisms driving these effects. We propose that distinct aspects of environmental change associated with N enrichment (resource limitation, asymmetric competition, and interactions with soil microbes) drive different aspects of plant response. We test this in greenhouse mesocosms, experimentally manipulating each factor across three ecosystems: tallgrass prairie, alpine tundra and desert grassland. We found that resource limitation controlled productivity responses to N enrichment in all systems. Asymmetric competition was responsible for diversity declines in two systems. Plant community composition was impacted by both asymmetric competition and altered soil microbes, with some contributions from resource limitation. Results suggest there may be generality in the mechanisms of plant community change with N enrichment. Understanding these links can help us better predict N response across a wide range of ecosystems. © 2016 John Wiley & Sons Ltd/CNRS.

  15. Hyb-Seq: Combining Target Enrichment and Genome Skimming for Plant Phylogenomics

    Directory of Open Access Journals (Sweden)

    Kevin Weitemier

    2014-08-01

    Full Text Available Premise of the study: Hyb-Seq, the combination of target enrichment and genome skimming, allows simultaneous data collection for low-copy nuclear genes and high-copy genomic targets for plant systematics and evolution studies. Methods and Results: Genome and transcriptome assemblies for milkweed (Asclepias syriaca were used to design enrichment probes for 3385 exons from 768 genes (>1.6 Mbp followed by Illumina sequencing of enriched libraries. Hyb-Seq of 12 individuals (10 Asclepias species and two related genera resulted in at least partial assembly of 92.6% of exons and 99.7% of genes and an average assembly length >2 Mbp. Importantly, complete plastomes and nuclear ribosomal DNA cistrons were assembled using off-target reads. Phylogenomic analyses demonstrated signal conflict between genomes. Conclusions: The Hyb-Seq approach enables targeted sequencing of thousands of low-copy nuclear exons and flanking regions, as well as genome skimming of high-copy repeats and organellar genomes, to efficiently produce genome-scale data sets for phylogenomics.

  16. Hyb-Seq: Combining target enrichment and genome skimming for plant phylogenomics1

    Science.gov (United States)

    Weitemier, Kevin; Straub, Shannon C. K.; Cronn, Richard C.; Fishbein, Mark; Schmickl, Roswitha; McDonnell, Angela; Liston, Aaron

    2014-01-01

    • Premise of the study: Hyb-Seq, the combination of target enrichment and genome skimming, allows simultaneous data collection for low-copy nuclear genes and high-copy genomic targets for plant systematics and evolution studies. • Methods and Results: Genome and transcriptome assemblies for milkweed (Asclepias syriaca) were used to design enrichment probes for 3385 exons from 768 genes (>1.6 Mbp) followed by Illumina sequencing of enriched libraries. Hyb-Seq of 12 individuals (10 Asclepias species and two related genera) resulted in at least partial assembly of 92.6% of exons and 99.7% of genes and an average assembly length >2 Mbp. Importantly, complete plastomes and nuclear ribosomal DNA cistrons were assembled using off-target reads. Phylogenomic analyses demonstrated signal conflict between genomes. • Conclusions: The Hyb-Seq approach enables targeted sequencing of thousands of low-copy nuclear exons and flanking regions, as well as genome skimming of high-copy repeats and organellar genomes, to efficiently produce genome-scale data sets for phylogenomics. PMID:25225629

  17. Methods for nondestructive assay holdup measurements in shutdown uranium enrichment facilities

    International Nuclear Information System (INIS)

    Hagenauer, R.C.; Mayer, R.L. II.

    1991-09-01

    Measurement surveys of uranium holdup using nondestructive assay (NDA) techniques are being conducted for shutdown gaseous diffusion facilities at the Oak Ridge K-25 Site (formerly the Oak Ridge Gaseous Diffusion Plant). When in operation, these facilities processed UF 6 with enrichments ranging from 0.2 to 93 wt % 235 U. Following final shutdown of all process facilities, NDA surveys were initiated to provide process holdup data for the planning and implementation of decontamination and decommissioning activities. A three-step process is used to locate and quantify deposits: (1) high-resolution gamma-ray measurements are performed to generally define the relative abundances of radioisotopes present, (2) sizable deposits are identified using gamma-ray scanning methods, and (3) the deposits are quantified using neutron measurement methods. Following initial quantitative measurements, deposit sizes are calculated; high-resolution gamma-ray measurements are then performed on the items containing large deposits. The quantitative estimates for the large deposits are refined on the basis of these measurements. Facility management is using the results of the survey to support a variety of activities including isolation and removal of large deposits; performing health, safety, and environmental analyses; and improving facility nuclear material control and accountability records. 3 refs., 1 tab

  18. Department of Energy's safety and health program for enrichment plant workers is not adequately implemented

    International Nuclear Information System (INIS)

    Staats, E.B.

    1980-01-01

    The Department of Energy's (DOE's) program to protect the safety and health of employees at its contractor-operated uranium enrichment plants has not been fully implemented by DOE's Oak Ridge Operations Office. Appraisals and inspections of plant conditions are not as frequent and/or as thorough as required. Instead of independently investigating employee complaints, DOE has delegated this responsibility to the contractor. It is recommended that the Secretary of Energy make sure that Oak Ridge properly conducts inspections and appraisals and investigates and follows up on all employee complaints. He should also take steps to provide increased independence and objectivity in the Oak Ridge Operations Office's safety and health program. Furthermore, the Congress should authorize the Secretary of Energy to institute a program of non-reimbursable penalties and fines for violations of safety and health standards and procedures

  19. The effect of a combination of plant sterol-enriched foods in mildly hypercholesterolemic subjects.

    Science.gov (United States)

    Madsen, Martin B; Jensen, Anne-Mette; Schmidt, Erik B

    2007-12-01

    The purpose of this study was to evaluate the effect of low-fat products enriched with plant sterols in addition to a National Cholesterol Education Program step 1 diet on serum lipids and lipoproteins. This study was a double-blind, randomised, placebo-controlled cross-over design with a run-in period and 2 intervention periods, each lasting 4 weeks. A total of 46 mildly hypercholesterolemic subjects (age 50.6+/-9.8) completed the trial. The study products consisted of 20 g low-fat margarine (35% fat) and 250 ml low-fat milk (0.7% fat), in total delivering 2.3g plant sterols/d. Serum total and low-density lipoprotein cholesterol were significantly reduced by 5.5% (pUnilever Denmark A/S.

  20. Approach to IAEA material-balance verification at the Portsmouth Gas Centrifuge Enrichment Plant

    International Nuclear Information System (INIS)

    Gordon, D.M.; Sanborn, J.B.; Younkin, J.M.; DeVito, V.J.

    1983-01-01

    This paper describes a potential approach by which the International Atomic Energy Agency (IAEA) might verify the nuclear-material balance at the Portsmouth Gas Centrifuge Enrichment Plant (GCEP). The strategy makes use of the attributes and variables measurement verification approach, whereby the IAEA would perform independent measurements on a randomly selected subset of the items comprising the U-235 flows and inventories at the plant. In addition, the MUF-D statistic is used as the test statistic for the detection of diversion. The paper includes descriptions of the potential verification activities, as well as calculations of: (1) attributes and variables sample sizes for the various strata, (2) standard deviations of the relevant test statistics, and (3) the detection sensitivity which the IAEA might achieve by this verification strategy at GCEP

  1. A 2000-2010 years outlook of isotopic uranium enrichment

    International Nuclear Information System (INIS)

    Vasaru, G.

    1998-01-01

    The increase of the installed power in nuclear plants implies the following steps to be achieved: - developing a parallel industry for the nuclear fuel cycle able to ensure a rhythmic supply of natural uranium, possibly an isotopic enrichment of 235 U of around 1.2 - 3.2%, depending on the reactor system; - manufacturing the fuel elements and the operation of cycle back-end, which may, possibly, include a temporary storage of the irradiated fuel; - reprocessing the spend fuel; - radioactive waste processing in view of final disposal, as well as the recovery of un-spent uranium and of plutonium formed. The heavy water reactors of CANDU-PHW does not imply any isotopic enrichment but provides a lower burnup of only 7,000 MW day/tone. An enrichment to 1.2% in 235 U for this type of reactors could increase the burnup up to 20,000 MW day/tone. An advanced method of enriching 235 U is based on the Atomic Vapor Laser Isotop Separation (AVLIS). This procedure called AVLIS has several advantages which are pointed out in this paper, among which: a very high selectivity; high separation factors; a low energy consumption due to the fact that in the conditions of a selective photo ionization, the energy necessary to the process is only 6.2 eV for the separated 235 U atom vs 0.3 MeV in case of inertial separators or 3 MeV in case of gaseous diffusion procedure. With the current laser yields an energy consumption of 100 kWh/SWU is estimated for AVLIS procedures as compared with 2,400 kWh/SWU in case of gaseous diffusion; an almost entire extraction of 235 U, what ensures a more efficient utilisation of nuclear fuel. Due to its modular character and to potential improvement in the equipment which could be achieved, this procedure will ensure a reduction in the investment costs in the construction stage what will make AVLIS a substitute of the classical separation procedures

  2. The enrichment behavior of natural radionuclides in pulverized oil shale-fired power plants

    International Nuclear Information System (INIS)

    Vaasma, Taavi; Kiisk, Madis; Meriste, Tõnis; Tkaczyk, Alan Henry

    2014-01-01

    The oil shale industry is the largest producer of NORM (Naturally Occurring Radioactive Material) waste in Estonia. Approximately 11–12 million tons of oil shale containing various amounts of natural radionuclides is burned annually in the Narva oil shale-fired power plants, which accounts for approximately 90% of Estonian electricity production. The radionuclide behavior characteristics change during the fuel combustion process, which redistributes the radionuclides between different ash fractions. Out of 24 operational boilers in the power plants, four use circulating fluidized bed (CFB) technology and twenty use pulverized fuel (PF) technology. Over the past decade, the PF boilers have been renovated, with the main objective to increase the efficiency of the filter systems. Between 2009 and 2012, electrostatic precipitators (ESP) in four PF energy blocks were replaced with novel integrated desulphurization technology (NID) for the efficient removal of fly ash and SO 2 from flue gases. Using gamma spectrometry, activity concentrations and enrichment factors for the 238 U ( 238 U, 226 Ra, 210 Pb) and 232 Th ( 232 Th, 228 Ra) family radionuclides as well as 40 K were measured and analyzed in different PF boiler ash fractions. The radionuclide activity concentrations in the ash samples increased from the furnace toward the back end of the flue gas duct. The highest values in different PF boiler ash fractions were in the last field of the ESP and in the NID ash, where radionuclide enrichment factors were up to 4.2 and 3.3, respectively. The acquired and analyzed data on radionuclide activity concentrations in different PF boiler ashes (operating with an ESP and a NID system) compared to CFB boiler ashes provides an indication that changes in the fuel (oil shale) composition and boiler working parameters, as well as technological enhancements in Estonian oil shale fired power plants, have had a combined effect on the distribution patterns of natural radionuclides in

  3. Starch accumulation during hydroponic growth of spinach and basil plants under carbon dioxide enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Holbrook, G P; Hansen, J; Wallick, K; Zinnen, T M [North Illinois University, de Kalb, IL (USA). Dept. of Biological Sciences

    1993-04-01

    The effects of CO[sub 2] enrichment, photoperiod duration, and inorganic phosphate levels on growth and starch accumulaton by spinach and basil plants were studied in a commercial hydroponic facility. During a 3-week growth period, both species exhibited increased whole-plant fresh weight as a result of an increase in atmospheric CO[sub 2] concentration from 400 to 1500 mul/1. However, basil leaves exhibited a 1.5- to 2-fold greater increase in specific leaf weight (SLW), and accumulated starch to much greater levels than did leaves of spinach. At 1500 mul CO[sub 2]/1, starch accounted for up to 38% of SLW with basil compared to [lt] 10% of SLW with spinach. The maximum ratio of starch/chlorophyll was 55.0 in basil leaves vs 8.0 in spinach leaves. High ratio values were associated with the appearance of chlorotic symptoms in leaves of basil grown under CO[sub 2] enrichment, whereas spinach did not exhibit chlorosis. Increasing inorganic phosphate concentrations from 0.7 to 1.8 mM in the hydroponic medium did not appreciably affect leaf starch accumulation in either species. Starch accumulation in basil leaves was not consistently related to the duration of the photoperiod. However, photoperiod-induced changes in leaf starch levels were much greater in basil than spinach. The results clearly indicate that different horticultural crops can show diverse responses to CO[sub 2] enrichment, and thus highlight the need to develop individual growth strategies to optimize production quality of each species.

  4. Evaluation of gaseous emissions produced in the tests on the demonstration plant for sludge drying and incineration

    International Nuclear Information System (INIS)

    Lotito, V.; Spinosa, L.; Antonacci, R.; Mininni, G.

    2001-01-01

    Incineration is a valid alternative to other more diffused disposal systems (agricultural use, landfill), when they cannot be applied due to high pollutants concentrations or other unforeseeable constraints. However, it can cause severe air pollution by inorganic (heavy metals) and organic (PAHs, PCDDs, PCDFs) pollutants, particulate, NO x , CO and acidic compounds; this fact has raised public concern about incineration and has hindered a wider application of this practice. Water Research Institute of Italian National Research Council realised a demonstration plant mainly consisting of a fluidized bed furnace, a rotary kiln furnace, a dryer with heat recovery section, particulate and acidic compounds removal apparatuses, and set up a research programme to demonstrate that incineration is a safe operation and can comply the relevant legislation, as far as organic and inorganic micropollutants are concerned. A total of 40 tests were carried out (30 with the fluidized bed furnace and 10 with rotary kiln one) treating dewatered sludges (in many cases with the addition of high chlorinated compounds and Cu salts) or dried ones, under different operating conditions (furnace temperature, after-burner temperature, chlorine concentration). Particulate concentrations, and consequently heavy metals concentrations, at the stack resulted in any case under legal limits. As far as conventional pollutants are concerned, only HCl and CO overcame sometimes standards, mainly due to temporary operating up-sets. PAHs concentration resulted quite constant, thus demonstrating that tests were operated in steady-state and satisfactory conditions. Also dioxins and furans overcame sometimes standards, but no correlation was found with more severe tests conditions; it happened when plant up-set conditions occurred. Operation resulted quite satisfactory, but dryer operation required constant operators attention. In rotary kiln furnace a build up of solidified ashes occurred in counter

  5. Uranium enrichment. Technology, economics, capacity

    International Nuclear Information System (INIS)

    Voigt, W.R. Jr.; Saire, D.E.; Gestson, D.K.; Peske, S.E.; Vanstrum, P.R.

    1983-01-01

    Large-scale enrichment of uranium has now been carried out for 40 years. While the gaseous diffusion process was the original choice of several countries and continues today to provide the major component of the world production of separative work, the last two decades have witnessed the development of a number of alternative processes for enrichment. These processes, which are being studied and deployed around the world, offer a wide range of technical and economic characteristics which will be useful in assuring adequate capacity to meet projected reactor fuel market needs through the rest of this century at competitive prices. With present uncertainties in future enriched uranium needs, it is apparent that flexibility in the deployment and operation of any enrichment process will be one of the prime considerations for the future. More economical production of separative work not only can have a beneficial impact on reactor fuel costs, but also tends to conserve natural uranium resources. This paper reviews the world scene in the enrichment component of the fuel cycle, including existing or planned commercial-scale facilities and announced R+D efforts on various processes. (author)

  6. Uranium enrichment: technology, economics, capacity

    Energy Technology Data Exchange (ETDEWEB)

    Voigt, Jr., W. R.; Vanstrum, P. R.; Saire, D. E.; Gestson, D. K.; Peske, S. E.

    1982-08-01

    Large-scale enrichment of uranium has now been carried out for 40 years. While the gaseous diffusion process was the original choice of several countries and continues today to provide the major component of the world production of separative work, the last two decades have witnessed the development of a number of alternative processes for enrichment. These processes, which are being studied and deployed around the world, offer a wide range of technical and economic characteristics which will be useful in assuring adequate capacity to meet projected reactor fuel market needs through the rest of this century at competitive prices. With present uncertainties in future enriched uranium needs, it is apparent that flexibility in the deployment and operation of any enrichment process will be one of the prime considerations for the future. More economical production of separative work not only can have a beneficial impact on reactor fuel costs, but also tends to conserve natural uranium resources. This paper reviews the world scene in the enrichment component of the fuel cycle, including existing or planned commercial-scale facilities and announced R and D efforts on various processes.

  7. Uranium enrichment: technology, economics, capacity

    International Nuclear Information System (INIS)

    Voigt, W.R. Jr.; Vanstrum, P.R.; Saire, D.E.; Gestson, D.K.; Peske, S.E.

    1982-01-01

    Large-scale enrichment of uranium has now been carried out for 40 years. While the gaseous diffusion process was the original choice of several countries and continues today to provide the major component of the world production of separative work, the last two decades have witnessed the development of a number of alternative processes for enrichment. These processes, which are being studied and deployed around the world, offer a wide range of technical and economic characteristics which will be useful in assuring adequate capacity to meet projected reactor fuel market needs through the rest of this century at competitive prices. With present uncertainties in future enriched uranium needs, it is apparent that flexibility in the deployment and operation of any enrichment process will be one of the prime considerations for the future. More economical production of separative work not only can have a beneficial impact on reactor fuel costs, but also tends to conserve natural uranium resources. This paper reviews the world scene in the enrichment component of the fuel cycle, including existing or planned commercial-scale facilities and announced R and D efforts on various processes

  8. Diffusion

    International Nuclear Information System (INIS)

    Kubaschewski, O.

    1983-01-01

    The diffusion rate values of titanium, its compounds and alloys are summarized and tabulated. The individual chemical diffusion coefficients and self-diffusion coefficients of certain isotopes are given. Experimental methods are listed which were used for the determination of diffusion coefficients. Some values have been taken over from other studies. Also given are graphs showing the temperature dependences of diffusion and changes in the diffusion coefficient with concentration changes

  9. Temporal relationships between the variations of diffuse gaseous emanations and the explosive activity of some active volcanoes of Costa-Rica, examples at the Arenal, Irazu and at the Rincon de la Vieja

    International Nuclear Information System (INIS)

    Baubron, J.C.; Allard, P.; Hammouya, G.; Soto, G.J.

    1996-01-01

    The surveillance of the temporal evolution of radon and helium concentrations in the carbon dioxide of crater fumaroles and gaseous emanations is performed since 1992 on the Irazu, Arenal, Poas and Rincon de la Vieja volcanoes in Costa-Rica. The 3 He/ 4 He ratio is used as an indicator of the deep origin of the volcanic gas while radon is an indicator of the CO 2 flux. Radon measurements performed on the Irazu show a continuous decay of radon concentration in the intra-crater fumaroles with an important increase of the gaseous flux since 1992. On the contrary, the external fumaroles on the NW flank were characterized by an important increase in radon concentration in 1994 with a stable flux. The radon surveillance performed in soils around the volcano has shown an intense increase of the diffuse gaseous flows probably linked to the micro-seismic activity of the volcano. Similar observations are reported for the Rincon de la Vieja volcano and correlated with its eruptive history and its phreatic and phreato-magmatic activity. Short paper. (J.S.)

  10. Gaseous 3-pentanol primes plant immunity against a bacterial speck pathogen, Pseudomonas syringae pv. tomato via salicylic acid and jasmonic acid-dependent signaling pathways in Arabidopsis.

    Science.gov (United States)

    Song, Geun C; Choi, Hye K; Ryu, Choong-Min

    2015-01-01

    3-Pentanol is an active organic compound produced by plants and is a component of emitted insect sex pheromones. A previous study reported that drench application of 3-pentanol elicited plant immunity against microbial pathogens and an insect pest in crop plants. Here, we evaluated whether 3-pentanol and the derivatives 1-pentanol and 2-pentanol induced plant systemic resistance using the in vitro I-plate system. Exposure of Arabidopsis seedlings to 10 μM and 100 nM 3-pentanol evaporate elicited an immune response to Pseudomonas syringae pv. tomato DC3000. We performed quantitative real-time PCR to investigate the 3-pentanol-mediated Arabidopsis immune responses by determining Pathogenesis-Related (PR) gene expression levels associated with defense signaling through salicylic acid (SA), jasmonic acid (JA), and ethylene signaling pathways. The results show that exposure to 3-pentanol and subsequent pathogen challenge upregulated PDF1.2 and PR1 expression. Selected Arabidopsis mutants confirmed that the 3-pentanol-mediated immune response involved SA and JA signaling pathways and the NPR1 gene. Taken together, this study indicates that gaseous 3-pentanol triggers induced resistance in Arabidopsis by priming SA and JA signaling pathways. To our knowledge, this is the first report that a volatile compound of an insect sex pheromone triggers plant systemic resistance against a bacterial pathogen.

  11. Gaseous 3-pentanol primes plant immunity against a bacterial speck pathogen, Pseudomonas syringae pv. tomato via salicylic acid and jasmonic acid-dependent signaling pathways in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Geun Cheol eSong

    2015-10-01

    Full Text Available 3-Pentanol is an active organic compound produced by plants and is a component of emitted insect sex pheromones. A previous study reported that drench application of 3-pentanol elicited plant immunity against microbial pathogens and an insect pest in crop plants. Here, we evaluated whether 3-pentanol and the derivatives 1-pentanol and 2-pentanol induced plant systemic resistance using the in vitro I-plate system. Exposure of Arabidopsis seedlings to 10 M and 100 nM 3-pentanol evaporate elicited an immune response to Pseudomonas syringae pv. tomato DC3000. We performed quantitative real-time PCR to investigate the 3-pentanol-mediated Arabidopsis immune responses by determining Pathogenesis-Related (PR gene expression levels associated with defense signaling through SA, JA, and ethylene signaling pathways. The results show that exposure to 3-pentanol and subsequent pathogen challenge upregulated PDF1.2 and PR1 expression. Selected Arabidopsis mutants confirmed that the 3-pentanol-mediated immune response involved salicylic acid (SA and jasmonic acid (JA signaling pathways and the NPR1 gene. Taken together, this study indicates that gaseous 3-pentanol triggers induced resistance in Arabidopsis by priming SA and JA signaling pathways. To our knowledge, this is the first report that a volatile compound of an insect sex pheromone triggers plant systemic resistance against a bacterial pathogen.

  12. On-Line Enrichment Monitor (OLEM) Phase II Final Report Techniques and Equipment for Safeguards at Gas Centrifuge Enrichment Plants

    Energy Technology Data Exchange (ETDEWEB)

    Younkin, James R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Garner, James R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-04-01

    Over the last five years, OLEM has been a collaborative development effort involving the IAEA, LANL, ORNL, URENCO, and the NNSA. The collective team has completed the following: design and modelling, software development, hardware integration, testing with the ORNL UF6 Flow Loop, a field trial at the Urenco facility in Almelo, the Netherlands, and a Demonstration at the Urenco USA facility in Eunice, New Mexico. This combined effort culminated in the deployment of several OLEM collection nodes in Iran. These OLEM units are one unattended monitoring system component of the Joint Comprehensive Plan of Action allowing the International Atomic Energy Agency to verify Iran’s compliance with the enrichment production aspects of the agreement.

  13. History of enrichment research at the CEA

    International Nuclear Information System (INIS)

    Camarcat, N.

    1996-01-01

    French researches about uranium enrichment have been carried out at the CEA for about 40 years. In the beginning, these researches were considered as marginal and were carried out by a small team from the Powders Central Laboratory. They became intensive since 1955 and culminated in 1967 with the conception of Pierrelatte's factory. Several processes were studied: the gaseous diffusion, the chemical treatments, the centrifugation, the laser and electromagnetic separation processes on atomic and molecular vapors. Only a few of them were fully developed. This paper summarizes the development of these different processes in their historical context. (J.S.). 1 fig

  14. Retention of gaseous isotopes

    International Nuclear Information System (INIS)

    Yarbro, O.O.; Mailen, J.C.; Stephenson, M.J.

    1977-01-01

    Retention of gaseous fission products during fuel reprocessing has, in the past, been limited to a modest retention of 131 I when processing fuels decayed less than about 180 days. The projected rapid growth of the nuclear power industry along with a desire to minimize environmental effects is leading to the reassessment of requirements for retention of gaseous fission products, including 131 I, 129 I, 85 Kr, 3 H, and 14 C. Starting in the late 1960s, a significant part of the LMFBR reprocessing development program has been devoted to understanding the behavior of gaseous fission products in plant process and effluent streams and the development of advanced systems for their removal. Systems for iodine control include methods for evolving up to 99% of the iodine from dissolver solutions to minimize its introduction and distribution throughout downstream equipment. An aqueous scrubbing system (Iodox) using 20 M HNO 3 as the scrubbing media effectively removes all significant iodine forms from off-gas streams while handling the kilogram quantities of iodine present in head-end and dissolver off-gas streams. Silver zeolite is very effective for removing iodine forms at low concentration from the larger-volume plant off-gas streams. Removal of iodine from plant liquid effluents by solid sorbents either prior to or following final vaporization appears feasible. Krypton is effectively released during dissolution and can be removed from the relatively small volume head-end and dissolver off-gas stream. Two methods appear applicable for removal and concentration of krypton: (1) selective absorption in fluorocarbons, and (2) cryogenic absorption in liquid nitrogen. The fluorocarbon absorption process appears to be rather tolerant of the normal contaminants (H 2 O, CO 2 , NOsub(x), and organics) present in typical reprocessing plant off-gas whereas the cryogenic system requires an extensive feed gas pretreatment system. Retention of tritium in a reprocessing plant is

  15. An integrated video- and weight-monitoring system for the surveillance of highly enriched uranium blend down operations

    International Nuclear Information System (INIS)

    Lenarduzzi, R.; Castleberry, K.; Whitaker, M.; Martinez, R.

    1998-01-01

    An integrated video-surveillance and weight-monitoring system has been designed and constructed for tracking the blending down of weapons-grade uranium by the US Department of Energy. The instrumentation is being used by the International Atomic Energy Agency in its task of tracking and verifying the blended material at the Portsmouth Gaseous Diffusion Plant, Portsmouth, Ohio. The weight instrumentation developed at the Oak Ridge National Laboratory monitors and records the weight of cylinders of the highly enriched uranium as their contents are fed into the blending facility while the video equipment provided by Sandia National Laboratory records periodic and event triggered images of the blending area. A secure data network between the scales, cameras, and computers insures data integrity and eliminates the possibility of tampering. The details of the weight monitoring instrumentation, video- and weight-system interaction, and the secure data network is discussed

  16. Automated analysis for large amount gaseous fission product gamma-scanning spectra from nuclear power plant and its data mining

    International Nuclear Information System (INIS)

    Weihua Zhang; Kurt Ungar; Ian Hoffman; Ryan Lawrie; Jarmo Ala-Heikkila

    2010-01-01

    Based on the Linssi database and UniSampo/Shaman software, an automated analysis platform has been setup for the analysis of large amounts of gamma-spectra from the primary coolant monitoring systems of a CANDU reactor. Thus, a database inventory of gaseous and volatile fission products in the primary coolant of a CANDU reactor has been established. This database is comprised of 15,000 spectra of radioisotope analysis records. Records from the database inventory were retrieved by a specifically designed data-mining module and subjected to further analysis. Results from the analysis were subsequently used to identify the reactor coolant half-life of 135 Xe and 133 Xe, as well as the correlations of 135 Xe and 88 Kr activities. (author)

  17. Evaluation of coverage of enriched UF6 cylinder storage lots by existing criticality accident alarms

    International Nuclear Information System (INIS)

    Lee, B.L. Jr.; Dobelbower, M.C.; Woollard, J.E.; Sutherland, P.J.; Tayloe, R.W. Jr.

    1995-03-01

    The Portsmouth Gaseous Diffusion Plant (PORTS) is leased from the US Department of Energy (DOE) by the United States Enrichment Corporation (USEC), a government corporation formed in 1993. PORTS is in transition from regulation by DOE to regulation by the Nuclear Regulatory Commission (NRC). One regulation is 10 CFR Part 76.89, which requires that criticality alarm systems be provided for the site. PORTS originally installed criticality accident alarm systems in all building for which nuclear criticality accidents were credible. Currently, however, alarm systems are not installed in the enriched uranium hexafluoride (UF 6 ) cylinder storage lots. This report analyzes and documents the extent to which enriched UF 6 cylinder storage lots at PORTS are covered by criticality detectors and alarms currently installed in adjacent buildings. Monte Carlo calculations are performed on simplified models of the cylinder storage lots and adjacent buildings. The storage lots modelled are X-745B, X-745C, X745D, X-745E, and X-745F. The criticality detectors modelled are located in building X-343, the building X-344A/X-342A complex, and portions of building X-330 (see Figures 1 and 2). These criticality detectors are those located closest to the cylinder storage lots. Results of this analysis indicate that the existing criticality detectors currently installed at PORTS are largely ineffective in detecting neutron radiation from criticality accidents in most of the cylinder storage lots at PORTS, except sometimes along portions of their peripheries

  18. Grazing damage to plants and gastropod and grasshopper densities in a CO 2-enrichment experiment on calcareous grassland

    Science.gov (United States)

    Ledergerber, Stephan; Thommen, G. Heinrich; Baur, Bruno

    Plant-herbivore interactions may change as atmospheric CO 2 concentrations continue to rise. We examined the effects of elevated atmospheric CO 2 and CO 2-exposure chambers on the grazing damage to plants, and on the abundances of potential herbivores (terrestrial gastropods and grasshoppers) in a calcareous grassland in the Jura mountains of Switzerland (village of Nenzlingen). Individuals of most plant species examined showed slight grazing damage. However, plots with CO 2 enrichment and plots with ambient atmosphere did not differ in the extent of grazing damage. Similarly, plots with CO 2 enrichment and plots with ambient atmosphere did not differ in either gastropod or grasshopper density. Experimental plots with and without chambers did not differ in the number of gastropods. However, the densities of gastropods and grasshoppers and extent of grazing damage to plants were generally lower in the experimental area than in the grassland outside the experimental field.

  19. A study of the annual doses to man from routine gaseous effluent releases of the Philippine Nuclear Power Plant Unit 1 (PNPP-1)

    International Nuclear Information System (INIS)

    Noriel, M.C.J.

    1983-01-01

    Individual and population integrated doses from radioactive gaseous releases of the Philippine Nuclear Power Plant 1 (PNPP-1) were calculated using a modified GASPAR Code. Input data consisted of meteorological and site data gathered from the PNPP-1 Final Analysis Report (FASR) population and agricultural data from the National Economic and Development Authority (NEDA) and the National Census and Statistics Office (NCSO). Usage factors were calculated based on Food and Nutrition Research Institute (FNRI) recommended dietary allowances for Filipinos. Results of population integrated dose calculations were used in identifying the critical nuclides, the critical body organs, and the critical pathway. Results from individual dose calculation were used in determining compliance with the dose limits set forth in Appendix D of Part 7 Code of Philippine Atomic Energy Commission (PAEC) regulations. (Author). 23 tabs.; 5 figs

  20. Cholesterol lowering effect of a soy drink enriched with plant sterols in a French population with moderate hypercholesterolemia

    Directory of Open Access Journals (Sweden)

    Bard Jean-Marie

    2008-10-01

    Full Text Available Abstract Background Plant sterols are an established non-pharmacological means to reduce total and LDL blood cholesterol concentrations and are therefore recommended for cholesterol management by worldwide-renown health care institutions. Their efficacy has been proven in many types of foods with the majority of trials conducted in spreads or dairy products. As an alternative to dairy products, soy based foods are common throughout the world. Yet, there is little evidence supporting the efficacy of plant sterols in soy-based foods. The objective of this study was to investigate the effect of a soy drink enriched with plant sterols on blood lipid profiles in moderately hypercholesterolemic subjects. Methods In a randomized, placebo-controlled double-blind mono-centric study, 50 subjects were assigned to 200 ml of soy drink either enriched with 2.6 g plant sterol esters (1.6 g/d free plant sterol equivalents or without plant sterols (control for 8 weeks. Subjects were instructed to maintain stable diet pattern and physical activity. Plasma concentrations of lipids were measured at initial visit, after 4 weeks and after 8 weeks. The primary measurement was the change in LDL cholesterol (LDL-C. Secondary measurements were changes in total cholesterol (TC, non-HDL cholesterol (non-HDL-C, HDL cholesterol (HDL-C and triglycerides. Results Regular consumption of the soy drink enriched with plant sterols for 8 weeks significantly reduced LDL- C by 0.29 mmol/l or 7% compared to baseline (p 96%, and products were well tolerated. Conclusion Daily consumption of a plant sterol-enriched soy drink significantly decreased total, non-HDL and LDL cholesterol and is therefore an interesting and convenient aid in managing mild to moderate hypercholesterolemia.