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Sample records for advanced heavy water

  1. Advances in heavy water reactors

    International Nuclear Information System (INIS)

    The current IAEA programme in advanced nuclear power technology promotes technical information exchange between Member States with major development programmes. The Technical Committee Meeting (TCM) on Advances in Heavy Water Reactors was organized by the IAEA in the framework of the activities of the International Working Group on Advanced Technologies for Water Cooled Reactors (IWGATWR) and hosted by the Atomic Energy of Canada Limited. Sixty-five participants from nine countries (Canada, Czech Republic, India, German, Japan, Republic of Korea, Pakistan, Romania and USA) and the IAEA attended the TCM. Thirty-four papers were presented and discussed in five sessions. A separate abstract was prepared for each of these papers. All recommendations which were addressed by the participants of the Technical Committee meeting to the IWGATWR have been submitted to the 5th IWGATWR meeting in September 1993. They were reviewed and used as input for the preparation of the IAEA programme in the area of advanced water cooled reactors. This TCM was mainly oriented towards advances in HWRs and on projects which are now in the design process and under discussion. Refs, figs and tabs

  2. General description of advanced heavy water reactor

    International Nuclear Information System (INIS)

    Advanced Heavy Water Reactor is a boiling light water cooled, heavy water moderated and vertical pressure tube type reactor with its design optimised for utilisation of thorium for power generation. The core consists of (Th-U233 )O2 and (Th-Pu)O2 fuel with a discharge burn up of 20,000 MWd/Te. This reactor incorporates several features to simplify the design, which eliminate certain systems and components. AHWR design is also optimised for easy replaceability of coolant channels, facilitation of in-service inspection and maintenance and ease of erection. The AHWR design also incorporates several passive systems for performing safety-related functions in the event of an accident. In case of LOCA, emergency coolant is injected through 4 accumulators of 260 m3 capacity directly into the core. Gravity driven water pool of capacity 6000 m3 serves to cool the core for 3 days without operator's intervention. Core submergence, passive containment isolation and passive containment cooling are the added features in AHWR. The paper describes the various process systems, core and fuel design, primary components and safety concepts of AHWR. Plant layout and technical data are also presented. The conceptual design of the reactor has been completed, and the detailed design and development is scheduled for completion in the year 2002. (author)

  3. Water chemistry features of advanced heavy water reactor

    International Nuclear Information System (INIS)

    Advanced Heavy Water Reactor (AHWR) being designed in India proposes to use Plutonium and Thorium as fuel. The objective is to extract energy from the uranium-233 formed from Thorium. It is a heavy water moderated and light water cooled tube type boiling water reactor. It is a heavy water moderated and light water cooled tube type boiling water reactor. It is a natural circulation reactor. Thus, it has got several advanced passive safety features built into the system. The various water coolant systems are listed below. i) Main Heat transport System ii) Feed water system iii) Condenser cooling system iv) Process water system and safety systems. As it is a tube type reactor, the radiolysis control differs from the normal boiling water reactor. The coolant enters the bottom of the coolant channel, boiling takes place and then the entire steam water mixture exits the core through the long tail pipes and reaches the moisture separator. Thus, there is a need to devise methods to protect the tail pipes from oxidizing water chemistry condition. Similarly, the moderator heavy water coolant chemistry differs from that of moderator system chemistry of PHWR. The reactivity worth per ppm of gadolinium and boron are low in comparison to PHWR. As a result, much higher concentration of neutron poison has to be added for planned shutdown, start up and for actuating SDS-2. The addition of higher concentration of neutron poison result in higher radiolytic production of deuterium and oxygen. Their recombination back to heavy water has to take into account the higher production of these gases. This paper also discusses the chemistry features of safety systems of AHWR. In addition, the presentation will cover the chemistry monitoring methodology to be implemented in AHWR. (author)

  4. Loss of feed water analyses of advanced Heavy Water Reactor

    International Nuclear Information System (INIS)

    The proposed Advanced Heavy Water Reactor (AHWR) is a 750 MWt vertical pressure tube type boiling light water cooled and heavy water moderated reactor. Passive design feature of this reactor is that the heat removal is achieved through natural circulation of primary coolant at all power level with no primary coolant pumps. The case analysed in this paper is the loss of feedwater to steam drum which results in decrease in heat removal from core. This also causes increase in reactor pressure. Further consequences depend upon various protective and engineered safeguard systems like relief system, reactor trip, isolation condenser and advanced accumulator. Analysis has been done using code RELAP5/MOD3.2. Various modeling aspects are discussed in this paper and predictions are made for different parameters like pressure, temperature, qualities and flow in different part of Primary Heat Transport (PHT) system. (author)

  5. Heavy water moderated reactors advances and challenges

    International Nuclear Information System (INIS)

    Nuclear energy is now considered a key contributor to world electricity production, with total installed capacity nearly equal to that of hydraulic power. Nevertheless, many important challenges lie ahead. Paramount among these is gaining public acceptance: this paper makes the basic assumption that public acceptance will improve if, and only if, nuclear power plants are operated safely and economically over an extended period of time. The first task, therefore, is to ensure that these prerequisites to public acceptance are met. Other issues relate to the many aspects of economics associated with nuclear power, include capital cost, operation cost, plant performance and the risk to the owner's investment. Financing is a further challenge to the expansion of nuclear power. While the ability to finance a project is strongly dependent on meeting public acceptance and economic challenges, substantial localisation of design and manufacture is often essential to acceptance by the purchaser. The neutron efficient heavy water moderated CANDU with its unique tube reactor is considered to be particularly well qualified to respond to these market challenges. Enhanced safety can be achieved through simplification of safety systems, design of the moderator and shield water systems to mitigate severe accident events, and the increased use of passive systems. Economics are improved through reduction in both capital and operating costs, achieved through the application of state-of-the-art technologies and economy of scale. Modular features of the design enhance the potential for local manufacture. Advanced fuel cycles offer reduction in both capital costs and fuelling costs. These cycles, including slightly enriched uranium and low grade fuels from reprocessing plants can serve to increase reactor output, reduce fuelling cost and reduce waste production, while extending resource utilisation. 1 ref., 1 tab

  6. Advanced light and heavy water reactors for improved fuel utilization

    International Nuclear Information System (INIS)

    On 26-29 November 1984 the Agency convened at its Headquarters in Vienna the Technical Committee and Workshop on Advanced Light and Heavy Water Reactor Technology in order to provide an opportunity to review and discuss the current status and recent development in the lay-out and design of advanced water reactor and to identify areas in which additional research and development are needed. The meeting was attended by 45 participants from 16 nations and 2 international organizations presenting 25 papers. The Conference presentations were divided into sessions devoted to the following topics: Advanced light water reactor programmes (6 papers); Advanced light water design, technology and physics (12 papers); Advanced heavy water reactors (7 papers). A separate abstract was prepared for each of these papers

  7. 20% inlet header break analysis of Advanced Heavy Water Reactor

    International Nuclear Information System (INIS)

    The proposed Advanced Heavy Water Reactor (AHWR) is a 750 MWt vertical pressure tube type boiling light water cooled and heavy water moderated reactor. A passive design feature of this reactor is that the heat removal is achieved through natural circulation of primary coolant at all power levels, with no primary coolant pumps. Loss of coolant due to failure of inlet header results in depressurization of primary heat transport (PHT) system and containment pressure rise. Depressurization activates various protective and engineered safety systems like reactor trip, isolation condenser and advanced accumulator, limiting the consequences of the event. This paper discusses the thermal hydraulic transient analysis for evaluating the safety of the reactor, following 20% inlet header break using RELAP5/MOD3.2. For the analysis, the system is discretized appropriately to simulate possible flow reversal in one of the core paths during the transient. Various modeling aspects are discussed in this paper and predictions are made for different parameters like pressure, temperature, steam quality and flow in different parts of the Primary Heat Transport (PHT) system. Flow and energy discharges into the containment are also estimated for use in containment analysis. (author)

  8. Advanced heavy water reactor pressure tube-easy replaceability

    International Nuclear Information System (INIS)

    Advanced Heavy Water Reactor (AHWR) is a 300 MWe vertical pressure tube type reactor. A coolant channel consists of pressure tube, made of Zr-2.5 % Nb, which is separated from cold calandria tube using garter spring spacers. The principal function of pressure tube is to support and locate the fuel assembly and allows light water coolant through fuel assembly by natural circulation. Since AHWR is designed for life of 100 years, it necessitates the replacement of pressure tubes during service life. Easy replaceability of pressure tube, along with surveillance requirements, has major bearing on the design of coolant channel assembly. The several systems and tools have been conceptualised to cater the needs for easy and quick replacement of a pressure tube during reactor shut down. This paper gives the highlights of the innovative design features of coolant channel, preliminary design and pre-requisites for replacement, and experimental programme for demonstration of easy replaceability. (author)

  9. Physics design of advanced heavy water reactor utilising thorium

    International Nuclear Information System (INIS)

    An Advanced Heavy Water Reactor (AHWR) is being developed in India with the aim of utilising thorium for power generation. AHWR is a vertical pressure tube type reactor cooled by boiling light water and moderated by heavy water. It has been optimised for the thorium cycle. The main design objective is to be self-sustaining in 233U with most of the power from the thorium fuel using plutonium as the external fissile feed. It incorporates several advanced safety features namely, heat removal through natural circulation and a negative void coefficient of reactivity. The reactor has been designed to produce 750 MW(th) at a discharge burnup of 20,000 MWd/H(e). The physics design of AHWR has followed an evolutionary path ranging from a seed and blanket concept to a simplified composite cluster to achieve a good thermal hydraulic coupling. We have designed a composite cluster using both kinds of fuel namely, (Th-UO2 and (Th-Pu)O2. With plutonium seed, negative void coefficient can be achieved by making the spectrum harder. This was done by using a pyrocarbon scatterer in the moderator. The void coefficient strongly depends on plutonium. As plutonium burns very rapidly, it is not possible to achieve uniformly negative void coefficient with burnup in this cluster. Alternatively, burnable poison can be used within the cluster to achieve negative void coefficient taking advantage of the flux redistribution and change in spectrum upon voiding. Here, it is possible to achieve almost constant void reactivity with burnup resulting in a good thermal hydraulic coupling. The cluster design presently incorporates a central burnable absorber region. Boiling light water coolant requires that the core power distribution be optimised with thermal hydraulic parameters. The peaking factors inside the cluster should be low so as to have significant margin in operational conditions and to avoid burnout in accident conditions. The variation of reactivity from cold clean to hot operating has

  10. Cooling of concrete structure in advanced heavy water reactor

    International Nuclear Information System (INIS)

    Innovative nuclear power plants are being designed by incorporation of passive systems to the extent possible for enhancing the safety by elimination of active components. BARC has designed Advanced Heavy Water Reactor (AHWR) incorporating several passive systems to facilitate the fulfillment of safety functions of the reactor during normal operation, residual heat removal, emergency core cooling, confinement of radioactivity etc. In addition to these passive systems, an innovative passive technology is being developed to protect, the concrete structure in high temperature zone (V1-volume). Passive Concrete Cooling System (PConCS) uses the principle of natural circulation to provide cooling outside the insulation cabinet encompassing high temperature piping. Cooling water is circulated from overhead GDWP in cooling pipes fixed over corrugated plate on outer surface of insulation cabinet and maintains low temperature of concrete structure. Modular construction of insulation cabinet and cooling pipes external to the concrete surface simplifies the design, construction and refurbishment if required. The paper describes the details of passive technology for concrete cooling. (author)

  11. Status of advanced technology and design for water cooled reactors: Heavy water reactors

    International Nuclear Information System (INIS)

    In 1987 the IAEA established the International Working Group on Advanced Technologies for Water-Cooled Reactors (IWGATWR). Within the framework of the IWGATWR the IAEA Technical Report on Status of Advanced Technology and Design for Water Cooled Reactors, Part I: Light Water Reactors and Part II: Heavy Water Reactors, has been undertaken to document the major current activities and trends of technological improvement and development for future water reactors. Part I of the report dealing with Light Water Reactors (LWRs) was published in 1988 (IAEA-TECDOC-479). Part II of the report covers Heavy Water Reactors (HWRs) and has now been prepared. This report is based largely upon submissions from Member States. It has been supplemented by material from the presentations at the IAEA Technical Committee and Workshop on Progress in Heavy Water Reactor Design and Technology held in Montreal, Canada, December 6-9, 1988. It is hoped that this part of the report, containing the status of advanced heavy water reactor technology up to 1988 and ongoing development programmes will aid in disseminating information to Member States and in stimulating international cooperation. Refs, figs and tabs

  12. A modern control room for Indian Advanced Heavy Water Reactor

    International Nuclear Information System (INIS)

    Advanced Heavy Water Reactor (AHWR) is a next generation nuclear power plant being developed by Bhabha Atomic Research Centre, India. AHWR is a vertical, pressure tube type, heavy-water-moderated, boiling light-water-cooled, innovative reactor, relying on natural circulation for core cooling in all operating and accident conditions. In addition, it incorporates various passive systems for decay heat removal, containment cooling and isolation. In addition to the many passive safety features, AHWR has state of the art I and C architecture based on extensive use of computers and networking. In tune with the many advanced features of the reactor, a centralized modern control room has been conceived for operation and monitoring of the plant. The I and C architecture enables the implementation of a fully computerised operator friendly control room with soft Human Machine Interfaces (HMI). While doing so, safety has been given due consideration. The control and monitoring of AHWR systems are carried out from the fully computer-based operator interfaces, except safety systems, for which only monitoring is provided from soft HMI. The control of the safety systems is performed from dedicated hardwired safety system panels. Soft HMI reduces the number of individual control devices and improves their reliability. The paper briefly describes the I and C architecture adopted for the AHWR plant along with the interfaces to the main and backup control rooms. There are many issues involved while introducing soft HMI based operator interfaces for Nuclear Power Plants (NPP) compared to the conventional plants. Besides discussing the implementation issues, the paper elaborates the design considerations that have undergone in the design of various components in the main control room especially operator workstations, shift supervisor console, safety system panels and large display panels. Mainly task based displays have been adopted for the routine operator interactions of the plant

  13. Toxicity of irradiated advanced heavy water reactor fuels.

    Science.gov (United States)

    Priest, N D; Richardson, R B; Edwards, G W R

    2013-02-01

    The good neutron economy and online refueling capability of the CANDU® heavy water moderated reactor (HWR) enable it to use many different fuels such as low enriched uranium (LEU), plutonium, or thorium, in addition to its traditional natural uranium (NU) fuel. The toxicity and radiological protection methods for these proposed fuels, unlike those for NU, are not well established. This study uses software to compare the fuel composition and toxicity of irradiated NU fuel against those of two irradiated advanced HWR fuel bundles as a function of post-irradiation time. The first bundle investigated is a CANFLEX® low void reactor fuel (LVRF), of which only the dysprosium-poisoned central element, and not the outer 42 LEU elements, is specifically analyzed. The second bundle investigated is a heterogeneous high-burnup (LEU,Th)O(2) fuelled bundle, whose two components (LEU in the outer 35 elements and thorium in the central eight elements) are analyzed separately. The LVRF central element was estimated to have a much lower toxicity than that of NU at all times after shutdown. Both the high burnup LEU and the thorium fuel had similar toxicity to NU at shutdown, but due to the creation of such inhalation hazards as (238)Pu, (240)Pu, (242)Am, (242)Cm, and (244)Cm (in high burnup LEU), and (232)U and (228)Th (in irradiated thorium), the toxicity of these fuels was almost double that of irradiated NU after 2,700 d of cooling. New urine bioassay methods for higher actinoids and the analysis of thorium in fecal samples are recommended to assess the internal dose from these two fuels. PMID:23274823

  14. On the physics design of Advanced Heavy Water Reactor (AHWR)

    International Nuclear Information System (INIS)

    Full text: The AHWR is a 920 MWth, vertical pressure tube type thorium-based reactor cooled by boiling light water and moderated by heavy water. The prime objective is to produce power utilizing thorium available abundantly in India from a relatively simple system with enhanced safety level. It is endowed with several innovative safety features such as negative coolant void reactivity, heat removal through natural circulation and passive containment cooling. The development of reactor design has drawn heavily on the experience generated through design and operation of Pressurised Heavy Water Reactors (PHWR) and Boiling Water Reactor (BWR) in India. It was an opportunity to develop a reactor system using thorium-based fuel and gain some valuable experience. A non-proliferative thorium/U-233 based closed fuel cycle is chosen for AHWR. Plutonium discharged from PHWRs is used as the fissile seed fuel with thorium for the generation of U-233 and then as a top-up fuel in the equilibrium core along with self-sustaining U-233 in the thorium matrix. The physics design has several challenges in achieving negative void reactivity, spatial core control, on-line fuelling and minimization of inventory of plutonium fuel. It is difficult to achieve negative coolant void coefficient in a heavy water moderated pressure tube type reactor. For this a multi-pronged approach involving pitch reduction, heterogeneous cluster design and use of mild absorbers is chosen. Plutonium bearing fuel is located separately in the outer region of the cluster with self-sustaining U-233 bearing fuel in the inner region of the cluster. A small amount of mild absorber is located in the centre of the cluster. The void coefficient varies with burnup and it is a challenge to have it negative throughout the core. The state of nuclear data for the elements of interest and type of neutron spectrum in the reactor puts heavy demand on the calculation models and validation of reactivity coefficients to ensure

  15. Advanced reactor design and safety objectives - The heavy water reactor perspective

    International Nuclear Information System (INIS)

    This paper provides a summary of the major requirements for future nuclear reactors from CANDU operating station owners based on the various studies and plans prepared. Most of the specific technical requirements for Advanced Heavy Water reactor Systems are based on systematic reviews of current operating CANDU stations to identify opportunities for generic improvements in reliability, operability, maintainability and to address emerging licensing or safety issues. Hence these requirements represent those for the evolutionary development of the Advanced Heavy Water Reactor systems factoring in the considerable operating experience of the CANDU stations. This evolutionary approach to the development of advanced heavy water reactors will be consistent with a philosophy of minimizing the risk to future reactor owners whose requirements are for a reliable, low cost unit

  16. Thermophysical properties of saturated light and heavy water for Advanced Neutron Source applications

    Energy Technology Data Exchange (ETDEWEB)

    Crabtree, A.; Siman-Tov, M.

    1993-05-01

    The Advanced Neutron Source is an experimental facility being developed by Oak Ridge National Laboratory. As a new nuclear fission research reactor of unprecedented flux, the Advanced Neutron Source Reactor will provide the most intense steady-state beams of neutrons in the world. The high heat fluxes generated in the reactor [303 MW(t) with an average power density of 4.5 MW/L] will be accommodated by a flow of heavy water through the core at high velocities. In support of this experimental and analytical effort, a reliable, highly accurate, and uniform source of thermodynamic and transport property correlations for saturated light and heavy water were developed. In order to attain high accuracy in the correlations, the range of these correlations was limited to the proposed Advanced Neutron Source Reactor`s nominal operating conditions. The temperature and corresponding saturation pressure ranges used for light water were 20--300{degrees}C and 0.0025--8.5 MPa, respectively, while those for heavy water were 50--250{degrees}C and 0.012--3.9 MPa. Deviations between the correlation predictions and data from the various sources did not exceed 1.0%. Light water vapor density was the only exception, with an error of 1.76%. The physical property package consists of analytical correlations, SAS codes, and FORTRAN subroutines incorporating these correlations, as well as an interactive, easy-to-use program entitled QuikProp.

  17. Thermophysical properties of saturated light and heavy water for advanced neutron source applications

    Energy Technology Data Exchange (ETDEWEB)

    Crabtree, A.; Siman-Tov, M.

    1993-05-01

    The Advanced Neutron Source is an experimental facility being developed by Oak Ridge National Laboratory. As a new nuclear fission research reactor of unprecedented flux, the Advanced Neutron Source Reactor will provide the most intense steady-state beams of neutrons in the world. The high heat fluxes generated in the reactor [303 MW(t) with an average power density of 4.5 MW/L] will be accommodated by a flow of heavy water through the core at high velocities. In support of this experimental and analytical effort, a reliable, highly accurate, and uniform source of thermodynamic and transport property correlations for saturated light and heavy water were developed. In order to attain high accuracy in the correlations, the range of these correlations was limited to the proposed Advanced Neutron Source Reactor's nominal operating conditions. The temperature and corresponding saturation pressure ranges used for light water were 20--300[degrees]C and 0.0025--8.5 MPa, respectively, while those for heavy water were 50--250[degrees]C and 0.012--3.9 MPa. Deviations between the correlation predictions and data from the various sources did not exceed 1.0%. Light water vapor density was the only exception, with an error of 1.76%. The physical property package consists of analytical correlations, SAS codes, and FORTRAN subroutines incorporating these correlations, as well as an interactive, easy-to-use program entitled QuikProp.

  18. Experimental studies on in-bundle ECCS injection for Advanced Heavy Water Reactor

    International Nuclear Information System (INIS)

    The Advanced Heavy Water Reactor (AHWR) being designed at BARC is an innovative reactor with Thorium utilization as its major objective. It has many advanced passive safety features. One such feature is passive injection of emergency coolant after postulated Loss of Coolant Accident (LOCA). A novel feature of this injection scheme is that the injection does not take place in the header/plenum as in other reactors, but directly in to the bundle. For this purpose, the fuel cluster incorporates a central water rod which communicates with the ECCS header. The water rod extends along full length of the fuel cluster. In event of LOCA in the Main Heat Transport (MHT) system, ECC water flows from the accumulator to the water rod through ECCS header. The water flows into the bundle through holes in the water rod. The AHWR fuel cluster has fuel pins arranged in three concentric rings (of 12, 18 and 24 pins) around the central rod. While it is ensured that water does reach the fuel cluster, whether it reaches the outer ring of pins is needs investigation as the pins are closely spaced (1-3 mm gap between adjacent rods). The objective of the present experiments is to determine under what conditions (ECC flow and decay heat), the ECC water is able to rewet and cool all the fuel pins. The experiments have been done in a short, instrumented fuel bundle simulating the geometry of the AHWR fuel cluster

  19. Advanced reactor design and safety objectives. The heavy water reactor perspective

    International Nuclear Information System (INIS)

    The development objectives of advanced heavy water reactors (AHWRs) should be guided by the requirements of the operating utilities. The paper provides a summary of the major requirements for future nuclear reactors from CANDU operating station owners based on the various studies and plans prepared. Most of the specific technical requirements for AHWR systems are based on systematic reviews of current operating CANDU stations. Hence these requirements represent those for the evolutionary development of AHWR systems, factoring in the considerable operating experiences of the CANDU stations. The requirements for the new HWR designs can be summarized under economic objectives, safety objectives, operational objectives and other utility requirements. 2 refs

  20. Sensitivity studies on nuclear data for thorium fuelled Advanced Heavy Water Reactor (AHWR)

    International Nuclear Information System (INIS)

    Sensitivity studies and uncertainty analyses on safety parameters for reactors are an important analysis tool for qualifying the basic nuclear cross-section data. It is also helpful in providing adequate margins at the design stage. In India, the design on Advanced Heavy water Reactor (AHWR) based on thorium is in its advanced stage of development. It is a first-of-a-kind reactor designed with many passive safety features which required to be qualified. In this paper, we discuss several types of sensitivity studies taken up for the integral parameters and reactivity coefficients for the AHWR-reference and the AHWR-LEU variant. The uncertainty studies are required to be taken to level higher where covariances can be established. It is important to analyse the uncertainties in a more rigorous manner

  1. Thermal hydraulic analysis due to the changes in heat removal for advanced heavy water reactor

    International Nuclear Information System (INIS)

    Advanced Heavy Water Reactor is a natural circulation light water cooled and heavy water moderated pressure tube reactor. Changes in heat removal by primary heat transport system of the reactor have significant impact on various important system parameters like pressures, qualities, reactor power and flows. Increase in heat removal leads to the cooldown of the system subsequently reducing pressure, void increase and changes in power and flows of the system. Decrease in heat removal leads to warm-up of the system subsequently raising pressure, void collapse, and changes in power and flows of the system. The behaviour is complex as system under consideration is natural circulation system. This article presents the results of simulations made with the RELAP5-MOD3.2 code that show first the impact of a decrease in feed water temperature on fluid temperature, steam drum pressure, core exit void, reactivity, reactor power, core flow, steam flow and clad temperature and secondly the impact of a loss of normal feed water flow on steam drum pressure, channel flow, core quality, clad surface temperature. For lowering of feed water temperature transient and in isolation condensers cold water injection, the reactor power increases and the reactor trips on the high power signal. Simultaneous flow increment due to the 2 phase natural circulation characteristic has caused the clad temperature to limit to their steady state value. In case of loss of feed transient the reactor trips on high pressure. The clad surface temperature rise from steady state operating value is marginal and it is well within the safety limit as per the acceptance criteria

  2. The key design features of the Indian advanced heavy water reactor

    International Nuclear Information System (INIS)

    The 235 MWe Indian Advanced Heavy Water Reactor (AHWR) is a vertical, pressure tube type, boiling light water cooled reactor. The three key specific features of design of the AHWR, having a large impact on its viability, safety and economics, relate to its reactor physics, coolant channel, and passive safety features. The reactor physics design is tuned for maximising use of thorium based fuel, and achieving a slightly negative void coefficient of reactivity. The fulfilment of these requirements has been possible through use of PuO2-ThO2 MOX, and ThO2 -U233O2 MOX in different pins of the same fuel cluster, and use of a heterogeneous moderator consisting of pyrolytic carbon and heavy water in 80%-20% volume ratio. The coolant channels of AHWR are designed for easy replaceability of pressure tubes, during normal maintenance shutdowns. The removal of pressure tube along with bottom end-fitting, using rolled joint detachment technology, can be done in AHWR coolant channels without disturbing the top end-fitting, tail pipe and feeder connections, and all other appendages of the coolant channel. The AHWR incorporates several passive safety features. These include core heat removal through natural circulation, direct injection of Emergency Core Coolant System (ECCS) water in fuel, passive systems for containment cooling and isolation, and availability of a large inventory of borated water in overhead Gravity Driven Water Pool (GDWP) to facilitate sustenance of core decay heat removal, ECCS injection, and containment cooling for three days without invoking any active systems or operator action. Incorporation of these features has been done together with considerable design simplifications, and elimination of several reactor grade equipment. A rigorous evaluation of feasibility of AHWR design concept has been completed. The economy enhancing aspects of its key design features are expected to compensate for relative complexity of the thorium fuel cycle activities required to

  3. Transient subchannel analysis of turbine trip without bypass with IC of advanced heavy water reactor

    International Nuclear Information System (INIS)

    Full text: The proposed advanced heavy water reactor (AHWR) is a 750 MWth vertical pressure tube type boiling light water cooled and heavy water moderated reactor. Safety analysis is carried out for various postulated initiating events (PIE) for AHWR. Turbine trip without bypass is one such PIE. Turbine trip results in rise in system pressure. Absence of bypass flow may lead to actuation of relief and safety valves depending upon system characteristics. System pressure rise activates various protective and engineered safeguard systems like reactor trip, isolation condenser and advanced accumulator limiting the consequences of the event. In this paper, a turbine trip without bypass is analysed, using a two-fluid code RELAPS/MOD3.2 [Fletcher, 1995] and subchannel analysis code COBRA IV-I. [Wheeler, 1976] Global analysis does not take into account the effect of different fuel pins with different peaking factors, effect of axial and radial cross flow mixing between adjacent subchannels. Combination of these two codes gives a better insight into the problem. The maximum rated reactor channel which houses 54 pin fuel bundle is modeled for COBRA IV-I simulation. The transient forcing function option of COBRA IV-I, validated by [Iwamura, 1994] with their flow-power transient experiments, has been used for transient thermal hydraulic parameter prediction for this study. Transient inlet pressure, inlet mass flow rate, inlet temperature, outlet enthalpy and the heat flux/power obtained from RELAPS /MOD3.2 simulation are among the boundary conditions employed on the COBRA-IV-I simulation. The thermal-hydraulic parameters predicted by RELAPS/MOD3.2 along with the effect of subchannel flow on the fuel element temperatures predicted by COBRA-IV-I are presented and discussed in this paper

  4. Development of advanced techniques for life management and inspection of advanced heavy water reactor (AWHR) coolant channel components

    International Nuclear Information System (INIS)

    Operating life of pressure tubes of Pressurized Heavy Water Reactor (PHWR) is limited due to the presence of various issues associated with the material like hydrogen pick up, delayed hydride cracking, axial elongation and increase in diameter due to irradiation creep and growth. Periodic monitoring of the health of the pressure tube under in-situ conditions is essential to ensure the safe operation of the reactor. New designs of reactor call for innovative design philosophy, modification in fabrication route of pressure tube, development of reactor specific tools, both analytical and hardware for assessing the fitness for service of the pressure tube. Feedback from existing reactors has enhanced the understanding about life limiting parameters. This paper gives an insight into the life limiting issues associated with pressure tube and the efforts pursued for development of life management techniques for coolant channel of Advanced Heavy Water Reactor (AHWR) designed in India. The tools and techniques for in-situ property/hydrogen measurement, pulsed eddy current technique for zirconium alloy in-homogeneity characterization, horizontal shear wave EMAT system for dissimilar metal weld inspection, sliver sampling of vertical channel etc. are elaborated in the paper. (author)

  5. Radio-toxicity of spent fuel of the advanced heavy water reactor.

    Science.gov (United States)

    Anand, S; Singh, K D S; Sharma, V K

    2010-01-01

    The Advanced Heavy Water Reactor (AHWR) is a new power reactor concept being developed at Bhabha Atomic Research Centre, Mumbai. The reactor retains many desirable features of the existing Pressurised Heavy Water Reactor (PHWR), while incorporating new, advanced safety features. The reactor aims to utilise the vast thorium resources available in India. The reactor core will use plutonium as the make-up fuel, while breeding (233)U in situ. On account of this unique combination of fuel materials, the operational characteristics of the fuel as determined by its radioactivity, decay heat and radio-toxicity are being viewed with great interest. Radio-toxicity of the spent fuel is a measure of potential radiological hazard to the members of the public and also important from the ecological point of view. The radio-toxicity of the AHWR fuel is extremely high to start with, being approximately 10(4) times that of the fresh natural U fuel used in a PHWR, and continues to remain relatively high during operation and subsequent cooling. A unique feature of this fuel is the peak observed in its radio-toxicity at approximately 10(5) y of decay cooling. The delayed increase in fuel toxicity has been traced primarily to a build-up of (229)Th, (230)Th and (226)Ra. This phenomenon has been observed earlier for thorium-based fuels and is confirmed for the AHWR fuel. This paper presents radio-toxicity data for AHWR spent fuel up to a period of 10(6) y and the results are compared with the radio-toxicity of PHWR. PMID:19776247

  6. Analytical modelling and study of the stability characteristics of the Advanced Heavy Water Reactor

    International Nuclear Information System (INIS)

    An analytical model has been developed to study the thermohydraulic and neutronic-coupled density-wave instability in the Indian Advanced Heavy Water Reactor (AHWR) which is a natural circulation pressure tube type boiling water reactor. The model considers a point kinetics model for the neutron dynamics and a lumped parameter model for the fuel thermal dynamics along with the conservation equations of mass, momentum and energy and equation of state for the coolant. In addition, to study the effect of neutron interactions between different parts of the core, the model considers a coupled multipoint kinetics equation in place of simple point kinetics equation. Linear stability theory was applied to reveal the instability of in-phase and out-of-phase modes in the boiling channels of the AHWR. The results indicate that the design configuration considered may experience both Ledinegg and Type I and Type II density-wave instabilities depending on the operating condition. Some methods of suppressing these instabilities were found out. In addition, it was found that the stability behavior of the reactor is greatly influenced by the void reactivity coefficient, fuel time constant, radial power distribution and channel inlet orificing. The delayed neutrons were found to have strong influence on the Type I and Type II instabilities. Decay ratio maps were predicted considering various operating parameters of the reactor, which are useful for its design. (author)

  7. Further evaluations of the toxicity of irradiated advanced heavy water reactor fuels.

    Science.gov (United States)

    Edwards, Geoffrey W R; Priest, Nicholas D

    2014-11-01

    The neutron economy and online refueling capability of heavy water moderated reactors enable them to use many different fuel types, such as low enriched uranium, plutonium mixed with uranium, or plutonium and/or U mixed with thorium, in addition to their traditional natural uranium fuel. However, the toxicity and radiological protection methods for fuels other than natural uranium are not well established. A previous paper by the current authors compared the composition and toxicity of irradiated natural uranium to that of three potential advanced heavy water fuels not containing plutonium, and this work uses the same method to compare irradiated natural uranium to three other fuels that do contain plutonium in their initial composition. All three of the new fuels are assumed to incorporate plutonium isotopes characteristic of those that would be recovered from light water reactor fuel via reprocessing. The first fuel investigated is a homogeneous thorium-plutonium fuel designed for a once-through fuel cycle without reprocessing. The second fuel is a heterogeneous thorium-plutonium-U bundle, with graded enrichments of U in different parts of a single fuel assembly. This fuel is assumed to be part of a recycling scenario in which U from previously irradiated fuel is recovered. The third fuel is one in which plutonium and Am are mixed with natural uranium. Each of these fuels, because of the presence of plutonium in the initial composition, is determined to be considerably more radiotoxic than is standard natural uranium. Canadian nuclear safety regulations require that techniques be available for the measurement of 1 mSv of committed effective dose after exposure to irradiated fuel. For natural uranium fuel, the isotope Pu is a significant contributor to the committed effective dose after exposure, and thermal ionization mass spectrometry is sensitive enough that the amount of Pu excreted in urine is sufficient to estimate internal doses, from all isotopes, as low

  8. Observations on the removal of gadolinium from the moderator system of pressurised heavy water reactor (PHWR) and advanced heavy water reactor (AHWR)

    International Nuclear Information System (INIS)

    Investigation on ion exchange removal of gadolinium taken as gadolinium nitrate, which is used as neutron poison in the moderator system of Pressurised Heavy Water Reactor (PHWR) and proposed to be used in Advanced Heavy Water Reactor (AHWR) was carried out. Mixed bed operation consisting of (a) strong acid cation resin (SAC) and strong base anion resin (SBA) and (b) strong acid action resin and acrylic acid based nitrate loaded weak base anion resin were employed for the removal gadolinium from its aqueous solution at pH 5. In the former case, the outlet of the mixed bed was highly alkaline, which resulted in precipitation of gadolinium hydroxide. In the latter case, the pH of the system never crossed 6 and gadolinium was effectively picked up on the resin without getting precipitated. Series operation consisting for strong acid cation resin followed by mixed bed column consisting of strong acid cation resin and strong base anion resin/acrylic acid based weak base anion resin was also investigated. In the first case where strong base anion resin was used, there was precipitation in the system owing to the increase in pH while in the case where weak base anion resin was used there was no problem of precipitation and gadolinium removed effectively and the pH was around 6. (author)

  9. Fuzzy-like PD controller for spatial control of advanced heavy water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Londhe, P.S., E-mail: pandurangl97@gmail.com [Research Scholar, SGGS Institute of Engineering and Technology, Vishnupuri, Nanded 431606 (India); Patre, B.M., E-mail: bmpatre@ieee.org [Department of Instrumentation Engineering, Shri Guru Gobind Singhji Institute of Engineering and Technology, Vishnupuri, Nanded 431 606 (India); Tiwari, A.P., E-mail: aptiwari@barc.gov.in [Reactor Control Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

    2014-07-01

    Highlights: • Highly non-linear model of AHWR is used for spatial power control. • A simple fuzzy-like PD (FZ-PD) control structure with robust rule base is developed. • Robust rule structure reduces the difficulties in design and tuning of controller. • Proposed FZ-PD structure shows robust and better transient performance. • Proposed FZ-PD controller is able to suppress spatial oscillations in AHWR. - Abstract: Spatial oscillations in the neutron flux distribution due to xenon reactivity feedback requires stringent control in large nuclear reactors, like advanced heavy water reactor (AHWR). If the spatial oscillations in the power distribution are not controlled, power density and rate of change of power at some locations in the reactor core may exceed limits of fuel failure due to ‘flux tilting’. Further, situations such as on-line refueling might cause transient variations in flux-shape from the nominal flux-shape. For analysis and control of spatial oscillations in AHWR, it is necessary to design a suitable control strategy, which will stabilize these oscillations. In this paper, a simplified scheme to design a conventional fuzzy logic controller for spatial control of AHWR is presented. This scheme known as fuzzy-like proportional derivative (FZ-PD) controller, uses robust PD (proportional derivative) type rule base. Due to robust rule base structure, tuning of scaling factors is greatly reduced. The non-linear coupled core neutronics-thermal hydraulics model of AHWR considered here represented by 90 first order differential equations. Through the dynamic simulations, it is observed that the designed FZ-PD controller is able to suppress spatial oscillations developed in AHWR and its performance is found to be robust.

  10. Fuel cycle flexibility in Advanced Heavy Water Reactor (AHWR) with the use of Th-LEU fuel

    International Nuclear Information System (INIS)

    The Advanced Heavy Water Reactor (AHWR) is being designed for large scale commercial utilization of thorium (Th) and integrated technological demonstration of the thorium cycle in India. The AHWR is a 920 MW(th), vertical pressure tube type cooled by boiling light water and moderated by heavy water. Heat removal through natural circulation and on-line fuelling are some of the salient features of AHWR design. The physics design of AHWR offers considerable flexibility to accommodate different kinds of fuel cycles. Our recent efforts have been directed towards a case study for the use of Th-LEU fuel cycle in a once-through mode. The discharged Uranium from Th-LEU cycle has proliferation resistant characteristics. This paper gives the initial core, fuel cycle characteristics and online refueling strategy of Th-LEU fuel in AHWR. (author)

  11. Indian advanced heavy water reactor for thorium utilisation and nuclear data requirements and status

    International Nuclear Information System (INIS)

    BARC is embarking on thorium utilisation program in a concerted and consistent manner to achieve all round capabilities in the entire Thorium cycle under the Advanced Heavy Water Reactor (AHWR) development program. Upgrading our nuclear data capability for thorium cycle is one of the main tasks of this program. This paper gives a brief overview of the physics design features of the AHWR. The basic starting point of the analysis has been the lattice simulation of the fuel cluster employing the WIMS-D4 code package with 1986 version of 69 group library. For the analysis of thorium cycle, the present multi group version contains the three major isotopes viz., 232Th, 233U and 233Pa. To correctly evaluate the fuel cycle we require many more isotopes of the Th burnup chain. With the help of NDS, IAEA, many other isotopes of interest in AHWR, actinides in the thorium burnup chain, burnable absorbers, etc., were generated. Some of them were added to the WIMS-D4 library and the results are discussed. The WIMS-D4 library is also being updated as part of the IAEA coordinated research project on Final Stage of WLUP with international cooperation. India is also taking part in CRP. The evaluation of AHWR lattice with this new library is presented. Some comments regarding the fission product data being used in WIMS libraries are given, which are tuned to U-Pu cycles. The measurements for 233U are rather old. Measurements in high energies are also very sparse. More attention by nuclear data community is required in this regard as well. India has also begun a modest program to assess the ADS concepts, with the aim of employing thermal reactor systems, such as AHWR. A one way coupled booster reactor concept is being analysed with available code systems and nuclear data. A brief summary of this concept is also being discussed in this paper. A general survey on the quality of the evaluated nuclear data of the major and minor isotopes of thorium cycle is also given. A major

  12. CFD analysis of flow and temperature distribution inside the calandria of Advanced Heavy Water Reactor

    International Nuclear Information System (INIS)

    Passive systems are being examined for the future AHWR reactor designs. One of these systems is the passive moderator cooling system, which removes heat from the moderator in case of a Station Black Out (SBO). The heavy-water moderator gets heated due to the residual heat from the core structures and rises upward due to buoyancy. This is cooled down in a heat exchanger and returns back to Calandria, completing a natural circulation loop. The natural circulation should provide sufficient cooling to prevent the increase of moderator (Calandria) pressure beyond safe limits. In this paper CFD investigations are carried out to study the temperature distributions and flow distribution inside the Calandria using a three-dimensional CFD code, OpenFoam 2.2.0. The results provide a band of operable mass flow rates which are safe for operation by virtue of prediction of hot spots in the Calandria. (author)

  13. Canadian heavy water production

    International Nuclear Information System (INIS)

    The paper reviews Canadian experience in the production of heavy water, presents a long-term supply projection, relates this projection to the anticipated long-term electrical energy demand, and highlights principal areas for further improvement that form the bulk of our research and development program on heavy water processes

  14. Heavy water and nonproliferation

    International Nuclear Information System (INIS)

    This report begins with a historical sketch of heavy water. The report next assesses the nonproliferation implications of the use of heavy water-moderated power reactors; several different reactor types are discussed, but the focus is on the natural uranium, on-power fueled, pressure tube reactor CANDU. The need for and development of on-power fueling safeguards is discussed. Also considered is the use of heavy water in plutonium production reactors as well as the broader issue of the relative nuclear leverage that suppliers can bring to bear on countries with natural uranium-fueled reactors as compared to those using enriched designs. The final chapter reviews heavy water production methods and analyzes the difficulties involved in implementing these on both a large and a small scale. It concludes with an overview of proprietary and nonproliferation constraints on heavy water technology transfer

  15. Advances in heavy water reactor technology. Proceedings of a technical committee meeting

    International Nuclear Information System (INIS)

    This IAEA meeting addressed both the status of national programmes and technical topics including advances in plant and system design and new plant features, development of pressure tube technologies, fuel and fuel cycle options, computer code development and verification, and safety and accident analysis

  16. Heavy water at Aswan

    International Nuclear Information System (INIS)

    A fertilizer factory is being built by Egyptian Chemical Industries (Kima) at Aswan on the upper Nile; it will produce a mixture of ammonium nitrate and calcium carbonate adjusted to contain 20.5% nitrogen. It is also proposed to construct a heavy water plant to be located at and integrated with the fertilizer factory. At the request of the Government of the United Arab Republic, the International Atomic Energy Agency sent an expert to carry out investigation of the technical, economic and other related aspects of the proposed production of heavy water. A report was submitted to the IAEA Director General. Its main conclusions can be summarized as follows: (1) Production of heavy water as a by-product of fertilizer manufacture at Aswan is technically feasible. Separation of deuterium from industrial hydrogen for this purpose could be done either by catalytic exchange or by liquefaction and distillation; the choice should depend on economic considerations. (2) The heavy water produced at Aswan should be competitive in cost with that produced elsewhere; this, however, would depend on whether firm contracts are obtained for the delivery of equipment at guaranteed prices and with guaranteed performance, and whether such prices are in reasonable agreement with preliminary estimates. (3) The future market for heavy water is difficult to predict. For one thing, there is a very large production capacity in the USA, most of which is idle due to lack of demand. Secondly, there is a relatively small production outside the USA that is sold at prices higher than that charged by the US Government. The future of the market is necessarily contingent upon the possibility of future free sale by the US Government. At the end of his report, the expert has also given his comments on possible further assistance to the project by IAEA

  17. Design, development and testing of 25 NB size Accumulator Isolation Passive Valve (AIPV) for Advanced Heavy Water Reactor (AHWR)

    International Nuclear Information System (INIS)

    In Advanced Heavy Water Reactor (AHWR), Emergency Core Cooling System (ECCS) is one of the engineered safety system provided to mitigate the consequences of Loss of Coolant Accident (LOCA) in the event of a break in the pressure boundary of Main Heat Transport (MHT) circuit. High Pressure Injection System of ECCS, is designed to provide coolant injection from advanced accumulators directly into the core for 15 minutes after LOCA. The injection pipe between each accumulator and ECCS header has a newly developed passive valve called Accumulator Isolation Passive Valve (AIPV). During normal reactor operation the MHT pressure will be 70 bar and accumulator pressure will be 55 bar. With rupture of large pipe, when the MHT system pressure falls down below 50 bar, the AIPV located between the accumulators and the ECC Headers, will open to provide coolant to the core. The AIPV is a self-acting type of valve requiring no external energy, i.e.neither air nor electric supply for its actuation. The AIPV serves not only as a passive isolation device but also as a flow control device. It is a non-standard, high pressure and high temperature valve and not manufactured by the valve industry worldwide. In the process of design and development of a 200 NB prototype AIPV for AHWR, a 25 NB size AIPV was designed and developed and successfully tested at Integral Test Loop (ITL). During several experiments carried out at ITL the functional capabilities of AIPV has been proved. The in-situ calibration and testing of AIPV in the plant without removing the same has also been established. This report deals with the role of AIPV in ECCS of AHWR, its design basis, tests performed at simulated conditions and test results with analysis. (author)

  18. Heavy water at Aswan

    International Nuclear Information System (INIS)

    In response to a request from the Government of the United Arab Republic, two experts were sent by IAEA, at the beginning of November, to Egypt, Mr. B.V. Nevsky (USSR) and Dr. Thayer (USA). Mr. Nevsky examined the possibilities and economics of extracting uranium from ores rich in phosphates, which are plentiful in Egypt. His report was not available when the Bulletin went to press. Mr. Thayer has reported to the Director General on the possibilities and the economic interest of producing heavy water by the electrolytic method as a by-product of an ammonium nitrate fertilizer factory now being constructed at Aswan. Dr. Thayer is a member of the Atomic Energy Division of the Du Pont Company and is working as a heavy water expert at the American Atomic Energy Commission's Savannah River project. We publish below excerpts from Dr. Thayer's report

  19. Heavy water reactors physics

    International Nuclear Information System (INIS)

    An important research programme on heavy water reactor physics has been carried out in France for quite a few years. The decision to build the EL 4 prototype and so to choose the heavy water gas cooled type has renewed the interest in this programme and at the same time given to it a more specific orientation A summary of the results gained in this field is presented in this paper. In the first part are described the experimental investigations, most of them were carried out in the criticality facility AQUILON II. The experiments are grouped in four parts - Systematic studies of lattices Buckling measurements. - Specific studies of gas-cooled lattices. - Fine structure, spectral indices measurements etc... - Measurements on lattices or samples containing Uranium of various enrichment or Plutonium. The second part is devoted to a summary of the theoretical studies. The whole results have allowed an improvement of the calculation methods, have led to a better understanding of the neutron balance in lattices, and have permitted the establishment of a set of formula to predict not only the clean fuel conditions but also the evolution of the nuclear properties with irradiation. Some specific studies on power reactor are quoted. (authors)

  20. Advanced eddy current technique for measurement of annular gap between pressure tube and calandria tube in Indian Pressurized Heavy Water Reactors (PHWRs)

    International Nuclear Information System (INIS)

    In Indian Pressurised Heavy Water Reactors (PHWRs), the PT (pressure tube) is designed to be nominally concentric with the encircling CT (calandria tube). Due to various factors PT becomes eccentric with respect to CT over the life of reactor. If this becomes excessive, hot PT will come in contact with cold CT. Such a cold spot could act as potential location for initiating blister formation and premature failure of PT. Hence it is important to periodically measure annular gap between PT and CT. An advanced eddy current technique has been successfully developed and incorporated in BARCIS (BARC Channel Inspection System) for measurement of PT-CT gap. (author). 4 refs., 3 figs

  1. Liquid sloshing in gravity driven water pool of Advanced Heavy Water Reactor - pool liquid under design seismic load and slosh control studies

    International Nuclear Information System (INIS)

    Sloshing phenomenon is well understood in regular cylindrical and rectangular liquid tanks subjected to earthquake. However, seismic behaviour of water in complex geometry such as a sectored annular tank, e.g., Gravity Driven Water Pool (GDWP) which is located in Advanced Heavy Water Reactor (AHWR) need to be investigated in detail in the view of safety significance. Initially, for validation of Computational Fluid Dynamics (CFD) procedure, square and four sectored square tanks are taken. Slosh height and liquid pressure are calculated over time through theoretical and experimental procedures. Results from theoretical and experimental approaches are compared with CFD results and found to be in agreement. The present work has two main objectives. The first one is to investigate the sloshing behaviour in an un-baffled and baffled three dimensional single sector of GDWP of AHWR under sinusoidal excitation. Other one is to study the sloshing in GDWP water using simulated seismic load along the three orthogonal directions. This simulated seismic load is generated from design basis floor response spectrum data (FRS) of AHWR building. For this, the annular tank is modelled along with water and numerical simulation is carried out. The sinusoidal and earthquake excitations are applied as acceleration force along with gravity. For the earthquake case, acceleration-time history is generated compatible to the design FRS of AHWR building. The free surface is captured by Volume of Fluid (VOF) technique and the fluid domain is solved by finite volume method while the structural domain is solved by finite element approach. Un-baffled and baffled tank configurations are compared to show the reduction in wave height under excitation. The interaction between the fluid and pool wall deformation is simulated using a partitioned fluid-structure coupling. In the earthquake case, a user subroutine function is developed to convert FRS in to time history of acceleration in three directions

  2. Fluid-phase transitions in light water and heavy water

    International Nuclear Information System (INIS)

    Phase transitions are important phenomena in water-cooled nuclear-fission reactors. In this study, liquid-vapour phase transitions and critical-point behaviour are considered. Special attention is given to the van der Waals model, asymptotic critical scaling, thermodynamic potentials and steam properties. Models and data are shown for light water and heavy water. The relevance to advanced Generation III reactors and proposed Generation IV reactors is assessed. (author)

  3. Evaluation of N,N-dihexyl octanamide as an alternative extractant for the reprocessing of Advanced Heavy Water Reactor spent fuel

    International Nuclear Information System (INIS)

    Advanced Heavy Water Reactor (AHWR) is being developed in India with the specific aim of utilizing thorium for power generation. AHWR sent fuel adds new dimensions to reprocessing by the presence of Pu along with 233U and Th in the spent fuel. This invokes the integration of PUREX and THOREX processes in some combination employing tri-n-butyl phosphate (TBP) as an extractant. However, separation scientists have identified certain problems with the use of TBP as extractant viz. third-phase formation and low separation factor (SF) values of U(VI) and Pu(VI) over Th, and poor decontamination factor (DF) values of U and Pu with respect to fission products. These problems are of particular concern in thorium fuel cycle

  4. Direction of Heavy Water Projects

    International Nuclear Information System (INIS)

    Summary of the activities performed by the Heavy Water Projects Direction of the Argentine Atomic Energy Commission from 1950 to 1983. It covers: historical data; industrial plant (based on ammonia-hydrogen isotopic exchange); experimental plant (utilizing hydrogen sulfides-water process); Module-80 plant (2-3 tons per year experimental plant with national technology) and other related tasks on research and development (E.A.C.)

  5. Heavy water extraction system

    International Nuclear Information System (INIS)

    In accordance with the present invention the tray for extracting liquid effluent from the humidifier section of the process is located in an intermediate position in the section, having a plurality of the trays of the section thereabove, with a balancing flow of heated water being admitted to the section beneath the extraction tray, to maintain substantially uniform loading of the trays in the humidifier section. The water being admitted in heat providing relation to the humidifier is divided into first and second portions, with the first portion admitted at the top of the humidifier section and the second portion substantially equal to the quantity of effluent extracted being admitted to the section beneath the extraction tray so as to maintain balance in the trays. The deuterium content of the gas, in passing through the trays above the extracting tray, is increased. The second water portion of the heater circuit is passed in heat exchanging relation with the effluent, to raise the temperature of the effluent prior to entry into the gas stripping portion of the plant wherein H2S gas is recovered for recycling. (author)

  6. Heavy water. A production alternative for Venezuela

    International Nuclear Information System (INIS)

    A survey of heavy water production methods is made. Main facts about isotopic and distillation methods, reforming and coupling to a Hydrogen distillation plant are presented. A feasibility study on heavy water production in Venezuela is suggested

  7. Nonlinear stability analysis of a reduced order model of nuclear reactors: A parametric study relevant to the advanced heavy water reactor

    International Nuclear Information System (INIS)

    Research highlights: → We model power oscillations in boiling water reactors using a lumped parameter model. → The nature and amplitudes of oscillations is obtained using a nonlinear analysis. → The method of multiple scales has been used for the analytical treatment. → Fuel temperature coefficient of reactivity determines the nature of oscillations. → The presented systematic method of analysis useful for reduced order reactor models. - Abstract: In this paper, we perform a parametric study of the nonlinear dynamics of a reduced order model for boiling water reactors (BWR) near the Hopf bifurcation point using the method of multiple scales (MMS). Analysis has been performed for general values of the parameters, but the results are demonstrated for parameter values of the model corresponding to the advanced heavy water reactor (AHWR). The neutronics of the AHWR is modeled using point reactor kinetic equations while a one-node lumped parameter model is assumed both for the fuel and the coolant for modeling the thermal-hydraulics. Nonlinearities in the heat transfer process are ignored and attention is focused on the nonlinearity introduced by the reactivity feedback. It is found that the steady-state operation of the AHWR mathematical model looses stability via. a Hopf bifurcation resulting in power oscillations as some typical bifurcation parameter like the void coefficient of reactivity is varied. The bifurcation is found to be subcritical for the parameter values corresponding to the AHWR. However, with a decrease in the fuel temperature coefficient of reactivity the bifurcation turns to supercritical implying global stability of the steady state operation in the linear stability regime. Moreover slight intrusion into the instability regime results in small-amplitude limit cycles leaving the possibility of retracting back to stable operation.

  8. Role of Passive Safety Features in Prevention And Mitigation of Severe Plant Conditions in Indian Advanced Heavy Water Reactor

    International Nuclear Information System (INIS)

    Pressing demands of economic competitiveness, the need for large-scale deployment, minimizing the need of human intervention, and experience from the past events and incidents at operating reactors have guided the evolution and innovations in reactor technologies. Indian innovative reactor 'AHWR' is a pressure-tube type natural circulation based boiling water reactor that is designed to meet such requirements, which essentially reflect the needs of next generation reactors. The reactor employs various passive features to prevent and mitigate accidental conditions, like a slightly negative void reactivity coefficient, passive poison injection to scram the reactor in event of failure of the wired shutdown systems, a large elevated pool of water as a heat sink inside the containment, passive decay heat removal based on natural circulation and passive valves, passive ECC injection, etc. It is designed to meet the fundamental safety requirements of safe shutdown, safe decay heat removal and confinement of activity with no impact in public domain, and hence, no need for emergency planning under all conceivable scenarios. This paper examines the role of the various passive safety systems in prevention and mitigation of severe plant conditions that may arise in event of multiple failures. For the purpose of demonstration of the effectiveness of its passive features, postulated scenarios on the lines of three major severe accidents in the history of nuclear power reactors are considered, namely; the Three Mile Island (TMI), Chernobyl and Fukushima accidents. Severe plant conditions along the lines of these scenarios are postulated to the extent conceivable in the reactor under consideration and analyzed using best estimate system thermal-hydraulics code RELAP5/Mod3.2. It is found that the various passive systems incorporated enable the reactor to tolerate the postulated accident conditions without causing severe plant conditions and core degradation

  9. Topical and working papers on heavy water requirements and availability

    International Nuclear Information System (INIS)

    The documents included in this report are: Heavy water requirements and availability; technological infrastructure for heavy water plants; heavy water plant siting; hydrogen and methane availability; economics of heavy water production; monothermal, water fed heavy water process based on the ammonia/hydrogen isotopic exchange; production strategies to meet demand projections; hydrogen availability; deuterium sources; the independent UHDE heavy water process

  10. Functional and performance evaluation of 28 bar hot shutdown passive valve (HSPV) at integral test loop (ITL) for advanced heavy water reactor (AHWR)

    International Nuclear Information System (INIS)

    During reactor shutdown in advanced heavy water reactor (AHWR), core decay heat is removed by eight isolation condensers (IC) submerged in gravity driven water pool. Passive valves are provided on the down stream of each isolation condenser. On increase in steam drum pressure beyond a set value, these passive valves start opening and establish steam flow by natural circulation between the four steam drums and corresponding isolation condensers under hot shutdown and therefore they are termed as Hot Shut Down Passive Valves (HSPVs). The HSPV is a self acting type valve requiring no external energy, i.e. neither air nor electric supply for actuation. This feature makes the valve functioning independent of external systems such as compressed air supply or electric power supply, thereby providing inherent safety feature in line with reactor design philosophy. The high pressure and high temperature HSPV s for nuclear reactor use, are non-standard valves and therefore not manufactured by the valve industry worldwide. In the process of design and development of a prototype valve for AHWR, a 28 bar HSPV was configured and successfully tested at Integral Test Loop (ITL) at Engineering Hall No.7. During ten continuous experiments spread over 14 days, the HSPV has proved its functional capabilities and its intended use in decay heat removal system. The in-situ pressure setting and calibration aspect of HSPV has also been successfully established during these experiments. This report gives an insight into the HSPV's functional behavior and role in reactor decay heat removal system. The report not only provides the quantitative measure of performance for 28 bar HSPV in terms of valve characteristics, pressure controllability, linearity and hysteresis but also sets qualitative indicators for prototype 80 bar HSPV, being developed for AHWR. (author)

  11. Production of heavy water in Romania

    International Nuclear Information System (INIS)

    The production of heavy water from natural water is based on the water-sulfide hydrogen isotope exchange, in association with the isotope distillation process in vacuum. Isotope distillation in vacuum at 100 mm Hg is used to obtain a final heavy-water concentration of at least 99.8%. To ensure an independent operation of the heavy-water pilot factory, hydrogen sulfide and sodium sulfide production technologies have been developed and certified. The Romanian laboratory studies and the small scale development experience have been implemented in ROMAG DROBETA Tr.Severin, the Romanian Heavy Water Plant

  12. Spatiotemporal Analysis of Heavy Metal Water Pollution in Transitional China

    OpenAIRE

    Huixuan Li; Yingru Li; Ming-Kuo Lee; Zhongwei Liu; Changhong Miao

    2015-01-01

    China’s socioeconomic transitions have dramatically accelerated its economic growth in last three decades, but also companioned with continuous environmental degradation. This study will advance the knowledge of heavy metal water pollution in China from a spatial–temporal perspective. Specifically, this study addressed the following: (1) spatial patterns of heavy metal water pollution levels were analyzed using data of prefecture-level cities from 2004 to 2011; and (2) spatial statistical...

  13. Heavy water: a distinctive and essential component of CANDU

    International Nuclear Information System (INIS)

    The exceptional properties of heavy water as a neutron moderator provide one of the distinctive features of CANDU reactors. Although most of the chemical and physical properties of deuterium and protium (mass 1 hydrogen) are appreciably different, the low terrestrial abundance of deuterium makes the separation of heavy water a relatively costly process, and so of considerable importance to the CANDU system. World heavy-water supplies are currently provided by the Girdler-Sulphide process or processes based on ammonia-hydrogen exchange. Due to cost and hazard considerations, new processes will be required for the production of heavy water in and beyond the next decade. Through AECL's development and refinement of wetproofed catalysts for the exchange of hydrogen isotopes between water and hydrogen, a family of new processes is expected to be deployed. Two monothermal processes, CECE (Combined Electrolysis and Catalytic Exchange, using water-to-hydrogen conversion by electrolysis) and CIRCE (Combined Industrially Reformed hydrogen and Catalytic Exchange, based on steam reforming of hydrocarbons), are furthest advanced. Besides its use for heavy-water production, the CECE process is a highly effective technology for heavy-water upgrading and for tritium separation from heavy (or light) water. (author). 10 refs., 1 tab., 7 figs

  14. Discovery of Interstellar Heavy Water

    Science.gov (United States)

    Butner, H. M.; Charnley, S. B.; Ceccarelli, C.; Rodgers, S. D.; Pardo, J. R.; Parise, B.; Cernicharo, J.; Davis, G. R.

    2007-04-01

    We report the discovery of doubly deuterated water (D2O, heavy water) in the interstellar medium. Using the James Clerk Maxwell Telescope and the Caltech Submillimeter Observatory 10 m telescope, we detected the 110-101 transition of para-D2O at 316.7998 GHz in both absorption and emission toward the protostellar binary system IRAS 16293-2422. Assuming that the D2O exists primarily in the warm regions where water ices have been evaporated (i.e., in a ``hot corino'' environment), we determine a total column density of N(D2O) of 1.0×1013 cm-2 and a fractional abundance of D2O/H2=1.7×10-10. The derived column density ratios for IRAS 16293-2422 are D2O/HDO=1.7×10-3 and D2O/H2O=5×10-5 for the hot corino gas. Steady state models of water ice formation, either in the gas phase or on grains, predict D2O/HDO ratios that are about 4 times larger than that derived from our observations. For water formation on grain surfaces to be a viable explanation, a larger H2O abundance than that measured in IRAS 16293-2422 is required. Alternatively, the observed D2O/HDO ratio could be indicative of gas-phase water chemistry prior to a chemical steady state being attained, such as would have occurred during the formation of this source. Future observations with the Herschel Space Observatory satellite will be important for settling this issue.

  15. Heavy water production by alkaline water electrolysis

    International Nuclear Information System (INIS)

    Several heavy water isotope production processes are reported in literature. Water electrolysis in combination with catalytic exchange CECE process is considered as a futuristic process to increase the throughput and reduce the cryogenic distillation load but the application is limited due to the high cost of electricity. Any improvement in the efficiency of electrolyzers would make this process more attractive. The efficiency of alkaline water electrolysis is governed by various phenomena such as activation polarization, ohmic polarization and concentration polarization in the cell. A systematic study on the effect of these factors can lead to methods for improving the efficiency of the electrolyzer. A bipolar and compact type arrangement of the alkaline water electrolyzer leads to increased efficiency and reduced inventory in comparison to uni-polar tank type electrolyzers. The bipolar type arrangement is formed when a number of single cells are stacked together. Although a few experimental studies have been reported in the open literature, CFD simulation of a bipolar compact alkaline water electrolyzer with porous electrodes is not readily available.The principal aim of this study is to simulate the characteristics of a single cell compact electrolyzer unit. The simulation can be used to predict the Voltage-Current Density (V-I) characteristics, which is a measure of the efficiency of the process.The model equations were solved using COMSOL multi-physics software. The simulated V-I characteristic is compared with the experimental data

  16. Heavy water lattices: Second panel report

    International Nuclear Information System (INIS)

    The panel was attended by prominent physicists from most of the laboratories engaged in the field of heavy water lattices throughout the world. The participants presented written contributions and status reports describing the past history and plans for further development of heavy-water reactors. Valuable discussions took place, during which recommendations for future work were formulated. Refs, figs, tabs

  17. Nuclear power plant life management processes: Guidelines and practices for heavy water reactors. Report prepared within the framework of the Technical Working Groups on Advanced Technologies for Heavy Water Reactors and on Life Management of Nuclear Power Plants

    International Nuclear Information System (INIS)

    The time is right to address nuclear power plant life management and ageing management issues in terms of processes and refurbishments for long term operation and license renewal aspects of heavy water reactors (HWRs) because some HWRs are close to the design life. In general, HWR nuclear power plant (NPP) owners would like to keep their NPPs in service as long as they can be operated safely and economically. This involves the consideration of a number of factors, such as the material condition of the plant, comparison with current safety standards, the socio-political climate and asset management/ business planning considerations. This TECDOC deals with organizational and managerial means to implement effective plan life management (PLiM) into existing plant in operating HWR NPPs. This TECDOC discusses the current trend of PLiM observed in NPPs to date and an overview of PLiM programmes and considerations. This includes key objectives of such programs, regulatory considerations, an overall integrated approach, organizational and technology infrastructure considerations, importance of effective plant data management and finally, human issues related to ageing and finally integration of PLiM with economic planning. Also general approach to HWR PLiM, including the key PLiM processes, life assessment for critical structures and components, conditions assessment of structures and components and obsolescence is mentioned. Technical aspects are described on component specific technology considerations for condition assessment, example of a proactive ageing management programme, and Ontario power generation experiences in appendices. Also country reports from Argentina, Canada, India, the Republic of Korea and Romania are attached in the annex to share practices and experiences to PLiM programme. This TECDOC is primarily addressed to both the management (decision makers) and technical staff (engineers and scientists) of NPP owners/operators and technical support

  18. Indian heavy water programme - challenges and opportunities

    International Nuclear Information System (INIS)

    Discovery of fission of uranium in 1939 opened up hitherto unknown possibilities for utilising the fission energy for use of mankind, mainly for the production of and electrical energy. It was realised that this nuclear energy could be an ideal substitute for the fast depleting fossil fuels which would one day get exhausted. Two main concepts of nuclear power reactor got evolved, one enriched uranium fuelled, ordinary water moderated reactor and another natural uranium fuelled heavy water moderated reactor. The concentration of uranium 235U needed for ordinary water moderated reactors is 3% but the naturally occurring uranium in India contains only 0.7% of 235U. The reactors utilising natural uranium as fuel require Heavy Water as moderator. The processing of uranium ore to achieve from 0.7% to 3% is highly complex. Recognising the fact that India has limited uranium resources but rich thorium resources, Dr. Bhabha formulated a three stage nuclear power generation programme for our country. The first generation reactors can use natural uranium as fuel with heavy water as moderator. Since the technology to generate such large scale heavy water to match the urgent need for nuclear power generation was not indigenously available, the technology available with Canada and France was utilised for installation of first generation heavy water plants in India. However, the peaceful nuclear experiment conducted by India in 1974 caused resentment among the countries that supplied Heavy Water technology to India and they stopped all technological help and assistance in nuclear field. Thereafter, it was the story of India going alone in heavy water production. That made India meets successfully all challenges on the way to installation, commissioning and sustained operation of all plants. Today we have six operating Heavy Water plants, spread all over the country. We have reached a stage, a change from a situation of crunch to a level of not only self sufficiency but to a state

  19. Water issues associated with heavy oil production.

    Energy Technology Data Exchange (ETDEWEB)

    Veil, J. A.; Quinn, J. J.; Environmental Science Division

    2008-11-28

    Crude oil occurs in many different forms throughout the world. An important characteristic of crude oil that affects the ease with which it can be produced is its density and viscosity. Lighter crude oil typically can be produced more easily and at lower cost than heavier crude oil. Historically, much of the nation's oil supply came from domestic or international light or medium crude oil sources. California's extensive heavy oil production for more than a century is a notable exception. Oil and gas companies are actively looking toward heavier crude oil sources to help meet demands and to take advantage of large heavy oil reserves located in North and South America. Heavy oil includes very viscous oil resources like those found in some fields in California and Venezuela, oil shale, and tar sands (called oil sands in Canada). These are described in more detail in the next chapter. Water is integrally associated with conventional oil production. Produced water is the largest byproduct associated with oil production. The cost of managing large volumes of produced water is an important component of the overall cost of producing oil. Most mature oil fields rely on injected water to maintain formation pressure during production. The processes involved with heavy oil production often require external water supplies for steam generation, washing, and other steps. While some heavy oil processes generate produced water, others generate different types of industrial wastewater. Management and disposition of the wastewater presents challenges and costs for the operators. This report describes water requirements relating to heavy oil production and potential sources for that water. The report also describes how water is used and the resulting water quality impacts associated with heavy oil production.

  20. Behavior of tritium in heavy water reactors

    International Nuclear Information System (INIS)

    In the ATR Fugen power station, the radiation control regarding the tritium in heavy water has been carried out since the heavy water was filled in the system of the reactor in November, 1977. At first, the concentration of tritium in heavy water was about 60 μCi/cc, but in November, 1981, it increased to about 1.3 mCi/cc, and the saturation concentration after 30 years is estimated to become about 17 mCi/cc. In this report, on the transfer of tritium to the work environment and general environment, its barrier, recovery, measurement and the protection against it, the experience in the Fugen power station is described. The heavy water system was constructed as the perfectly closed circuit by welding stainless steel, and a canned heavy water circulating pump has been used. The leak of heavy water in the steady operation is negligible, but attention must be paid to the transfer of tritium to the environment when the system is disassembled for the regular inspection. The measurement of tritium for individual exposure control, environment and released radioactivity, the tritium-removing equipment and protective suits, and the release of tritium to general environment are reported. (Kako, I.)

  1. Technical status study of heavy water enrichment

    International Nuclear Information System (INIS)

    Technical status study of heavy water enrichment in Indonesia and also in the world has been done. Heavy water enrichment processes have been investigated were water distillation, hydrogen distillation, laser enrichment, electrolysis and isotop exchange. For the isotop exchange, the chemical pair can be used were water-hydrogen sulphite, ammonium-hydrogen, aminomethane-hydrogen, and water-hydrogen. For the isotope exchange, there was carried out by mono thermal or bi thermal. The highest producer of heavy water is Canada, and the other producer is USA, Norwegian and India. The processes be used in the world are isotope exchange Girdler Sulphide (GS), distillation and electrolysis. Research of heavy water carried out in Batan Yogyakarta, has a purpose to know the characteristic of heavy water purification. Several apparatus which has erected were 3 distillation column: Pyrex glass of 2 m tall, stainless steel column of 3 m tall and steel of 6 m tall. Electrolysis apparatus is 50 cell electrolysis and an isotope exchange unit which has catalyst: Ni- Cr2O3 and Pt-Carbon. These apparatus were not ready to operate. (author)

  2. Research advances in heavy metal biosorption

    International Nuclear Information System (INIS)

    Biosorption of heavy metal has wide applications. The mechanisms of heavy metal biosorption, including complexation, ion exchange, microprecipitation and oxidation reduction, are presented. Thermodynamics and dynamics of biosorption are also discussed. Key factors of influencing biosorption, such as pH values, coexistence ions and temperature are explained. The research directions are explored. (authors)

  3. Topical and working papers on heavy water accountability and safeguards

    International Nuclear Information System (INIS)

    This report contains the following papers: 1) Statement of IAEA concerning safeguarding of heavy water; 2) Preliminary Canadian Comments on IAEA document on heavy water safeguards; 3) Heavy water accountability 03.10.78; 4) Heavy water accountability 05.04.79

  4. Spatiotemporal Analysis of Heavy Metal Water Pollution in Transitional China

    Directory of Open Access Journals (Sweden)

    Huixuan Li

    2015-07-01

    Full Text Available China’s socioeconomic transitions have dramatically accelerated its economic growth in last three decades, but also companioned with continuous environmental degradation. This study will advance the knowledge of heavy metal water pollution in China from a spatial–temporal perspective. Specifically, this study addressed the following: (1 spatial patterns of heavy metal water pollution levels were analyzed using data of prefecture-level cities from 2004 to 2011; and (2 spatial statistical methods were used to examine the underlying socioeconomic and physical factors behind water pollution including socioeconomic transitions (industrialization, urbanization, globalization and economic development, and environmental characteristic (natural resources, hydrology and vegetation coverage. The results show that only Cr pollution levels increased over the years. The individual pollution levels of the other four heavy metals, As, Cd, Hg, and Pb, declined. High heavy metal water pollution levels are closely associated with both anthropogenic activities and physical environments, in particular abundant mineral resources and industrialization prosperity. On the other hand, economic development and urbanization play important roles in controlling water pollution problems. The analytical findings will provide valuable information for policy-makers to initiate and adjust protocols and strategies for protecting water sources and controlling water pollution; thus improving the quality of living environments.

  5. Future trends in heavy water production

    International Nuclear Information System (INIS)

    World heavy water production has spanned nearly fifty years and, for much of that period, the commodity was often in short supply, but that situation has changed, at least in Canada. There are now adequate reserves of heavy water and sufficient installed production capacity to service Canadian domestic and export demands for the next ten years or beyond. More than 90 percent of the world's inventory of heavy water has been produced by the GS process but this may not be the method that is chosen when the time comes to expand heavy water production again. Other countries, such as India and Argentina, have already chosen ammonia-hydrogen exchange as an alternative technology for part of their domestic production programs. Despite the present surplus of heavy water, research and development of new technologies is very active, particularly in Canada and Japan, because it is recognized that there are still attractive opportunities for future production by processes that are both less expensive and environmentally more acceptable, than either the demonstrated GS process or ammonia-hydrogen alternative. This paper describes the prospects for some of these new processes, contrasts them with the present established methods and assesses the probable impact on the future supply situation

  6. Heavy water cycle in the CANDU reactor

    International Nuclear Information System (INIS)

    Hydrogen atom has two isotopes: deuterium 1H2 and tritium 1H3. The deuterium oxide D2O is called heavy water due to its density of 1105.2 Kg/m3. Another important physical property of the heavy water is the low neutron capture section, suitable to moderate the neutrons into natural uranium fission reactor as CANDU. Due to the fact that into this reactor the fuel is cooled into the pressure tubes surrounded by a moderator, the usage of D2O as primary heat transport (PHT) agent is mandatory. Therefore a large amount of heavy water (approx. 500 tons) is used in a CANDU reactor. Being a costly resource - it represents 20% of the initial plant capital cost, D2O management is required to preserve it. (author)

  7. Pressurized Heavy Water Reactor Fuel: Integrity, Performance and Advanced Concepts. Proceedings of the Technical Meetings held in Bucharest, 24-27 September 2012, and in Mumbai, 8-11 May 2013

    International Nuclear Information System (INIS)

    Seven Member States have operating pressurized heavy water reactors (PHWRs), and some of them are also planning new reactors of this type. The current type of PHWR uses natural uranium as the fuel and has an average burnup of 7000 MWd/t (megawatt days per metric tonne). To make these reactors economically competitive with other reactor types, the discharge burnup of PHWR fuel will need to be increased without affecting the integrity of the fuel pin and bundle. A significant increase in the discharge burnup of fuel is possible with the use of advanced fuel cycles in PHWRs. The advanced fuels can be slightly enriched uranium, reprocessed uranium from light water reactors, mixed oxide or thorium based fuels. At the same time, substantial savings in natural uranium resources can also be achieved through the possible extension of the discharge burnup of advanced fuels used in PHWRs without changing reactor hardware. Following the recommendation of the Technical Working Group on Fuel Performance and Technology, two technical meetings were held: Technical Meeting on Fuel Integrity during Normal Operation and Accident Conditions in PHWRs, 24–27 September 2012, Bucharest, Romania; and Technical Meeting on Advanced Fuel Cycles in PHWRs, 8–11 April 2013, Mumbai, India. Their objective was to update information on the performance of PHWR fuels, the status and trends in the use of advanced fuels in PHWRs and the technical readiness for the deployment of such fuel cycles in these types of reactor. This publication contains the proceedings of the two technical meetings, including a record of the discussions held during the various technical sessions

  8. Ageing management in heavy water plants

    International Nuclear Information System (INIS)

    With proper design and construction ageing can be minimized. It is important to understand the mechanics of ageing specific to service, develop baseline data and monitor to ensure that there are no premature failures especially where the service conditions are extreme and media used is highly corrosive and hazardous such as in heavy water plants. The key lies in an effective in-service inspection and determination of residual life for decision making vis-a-vis upgrading and ensuring safety. While quite a bit of work in this direction has been done in the Heavy Water Board, a lot more ground needs to be covered. (author)

  9. Recent advances in heavy quark theory

    Energy Technology Data Exchange (ETDEWEB)

    Wise, M. [California Institute of Technology, Pasadena, CA (United States)

    1997-01-01

    Some recent developments in heavy quark theory are reviewed. Particular emphasis is given to inclusive weak decays of hadrons containing a b quark. The isospin violating hadronic decay D{sub s}* {yields} D{sub s}{sup pi}{sup 0} is also discussed.

  10. Detection of gaseous heavy water leakage points in CANDU 6 pressurized heavy water reactors

    International Nuclear Information System (INIS)

    During reactor operation, the heavy water filled primary coolant system in a CANDU 6 Pressurized Heavy Water (PHWR) may leak through routine operations of the plant via components, mechanical joints, and during inadvertent operations etc. Early detection of leak points is therefore important to maintain plant safety and economy. There are many independent systems to monitor and recover heavy water leakage in a CANDU 6 PHWR. Methodology for early detection based on operating experience from these systems, is investigated in this paper. In addition, the four symptoms of D2O leakage, the associated process for clarifying and verifying the leakage, and the probable points of leakage are discussed. (author)

  11. Fast neutron flux in heavy water reactors

    International Nuclear Information System (INIS)

    The possibility of calculating the fast neutron flux in a natural uranium-heavy water lattice by superposition of the individual contributions of the different fuel elements was verified using a one-dimension Monte-Carlo code. The results obtained are in good agreement with experimental measurements done in the core and reflector of the reactor AQUILON. (author)

  12. Canadian heavy water production - 1970 to 1980

    International Nuclear Information System (INIS)

    In the last decade, heavy water production in Canada has progressed from the commissioning of a single unit plant in Nova Scotia to a major production industry employing 2200 persons and operating three plants with an aggregate annual production capability in excess of 1800 Mg. The decade opened with an impending crisis in the supply of heavy water due to failure of the first Glace Bay Heavy Water Plant and difficulty in commissioning the second Canadian plant at Port Hawkesbury. Lessons learned at this latter plant were applied to the Bruce plant where the first two units were under construction. When the Bruce units were commissioned in 1973 the rate of approach to design production rates was much improved, renewing confidence in Canada's ability to succeed in large scale heavy water production. In the early 1970's a decision was made to rehabilitate the Glace Bay plant using a novel flowsheet and this rebuilt plant commenced production in 1976. The middle of the decade was marked by two main events: changes in ownership of the operating plants and initiation of a massive construction program to support the forecast of a rapidly expanding CANDU power station construction program. New production units embodying the best features of their predecessors were committed at Bruce by Ontario Hydro and at La Prade, Quebec, by AECL. The high growth rate in electrical demand did not continue and some new plant construction was curtailed. The present installed production capacity will now probably be adequate to meet anticipated demand for the next decade. Canadian plants have now produced more than 7800 Mg of heavy water at a commercially acceptable cost and with a high degree of safety and compliance with appropriate environmental regulations

  13. Experiences in use of fresh water at Heavy Water Plants

    International Nuclear Information System (INIS)

    Heavy Water Board (HWB), an industrial organization under Department of Atomic Energy is primarily responsible for production of Heavy which is used as a Moderator and Coolant in the nuclear power reactors as well as research reactors. Two chemical exchange processes are being employed for industrial production of heavy water in India. H2S-H2O bi-thermal process requires approximately 35,000 tonnes of water to be processed to get one kg of nuclear grade water. Here surface water is the source of deuterium whereas H2S acts as deuterium carrier. Recently, HWB had indigenously developed front-end technology of ammonia-water exchange process for initial deuterium enrichment. In this process, water is the source of deuterium whereas NH3 acts as deuterium carrier. Moreover, these processes require elaborate heating and cooling arrangement in exchange process. Heating is accomplished through steam whereas cooling is effected through cooling and chilled water. This paper describes the measures adapted by HWB w.r.t. recycle and reuse and incorporating several process modifications and retrofitting in these plants to reduce consumption of this precious natural resource. As of now, cumulative water requirement for all six heavy water plants has drastically reduced from 2,50,000 m3 per day to the value of 61,000 m3 per day. (author)

  14. Advances in water resources technology

    Science.gov (United States)

    The presentation of technological advances in the field of water resources will be the focus of Advances in Water Resources Technology, a conference to be held in Athens, Greece, March 20-23, 1991. Organized by the European Committee for Water Resources Management, in cooperation with the National Technical University of Athens, the conference will feature state-of-the art papers, contributed original research papers, and poster papers. Session subjects will include surface water, groundwater, water resources conservation, water quality and reuse, computer modeling and simulation, real-time control of water resources systems, and institutions and methods for technology.The official language of the conference will be English. Special meetings and discussions will be held for investigating methods of effective technology transfer among European countries. For this purpose, a wide representation of research institutions, universities and companies involved in water resources technology will be attempted.

  15. Outlook for Heavy-Water Reactors

    International Nuclear Information System (INIS)

    For large capacity units heavy-water reactors have already established an economic position competitive with any other nuclear or conventional electric generators in certain quite normal circumstances. With continued development they are expected to maintain this position and contribute a large fraction of the world's power demand into the indefinite future and extend to other large-scale uses such as desalting water. The grounds for this forecast are shown to be firmly based on a low-fuelling cost despite any likely rise in the price of uranium, together with extreme flexibility to adapt the fuel cycle to meet any changes in the market of fuel supply and reprocessing. Appropriate use of thorium with uranium is likely in the long term. As the scale of use expands, the cost of fabricating fuel and of producing heavy water will fall. Very few large heavy-water power reactors have yet been built and as experience is gained the cost of construction will fall. An important near-term development will be the practice of taking heat from the fuel direct to generate the working steam. In the longer term as improved materials are developed for higher temperatures the thermal to electrical conversion efficiency will be raised. With all these improvements in view, a long-term competitive position is foreseen. Details are given of several fuel cycle changes showing the inventories of fuel and heavy water involved in meeting market changes and the expectation of net fuel cycle costs being held in the range 0.3 to 0.6 mill/kWh in terms of to-day's dollar values despite a rise in the cost of uranium. The analysis shows possible interaction with other types of reactor including breeders. Reasons are given for welcoming any possible future competition or partnership from these types in meeting the growing world demand for harnessed energy. (author)

  16. Heavy-Water Power Reactors. Proceedings Of A Symposium

    International Nuclear Information System (INIS)

    Proceedings of a Symposium organized by the IAEA and held in Vienna, 11-15 September 1967. The timeliness of the meeting was underlined by the large gathering of over 225 participants from 28 countries and three international organizations. Contents: Experience with heavy-water power and experimental reactors and projects (14 papers); New and advanced power reactor designs and concepts (8 papers); Development programmes and thorium cycle (9 papers); Economics and prospects of heavy-water power reactors (7 papers); Physics and fuel management (8 papers); Fuels (5 papers); Safety, control and engineering (6 papers); Panel discussion. Except for one Russian paper, which is published in English, each paper is in its original language (49 English and 8 French) and is preceded by an abstract in English with a second one in the original language if this is not English. Discussions are in English. (author)

  17. Sediment, water pollution indicators for heavy metals

    International Nuclear Information System (INIS)

    The complexity of an aquatic system requires consideration of its dynamics: spatial and temporal variations of physical, chemical and biological. Heavy metals have peculiar behavior in the aquatic system and may not be available in the waters, but on sediments.The sub-basin of the Sarandi stream is responsible for the contamination of Pampulha Lake. The Instituto Mineiro das Águas – IGAM - uses tool for monitoring the quality of surface water for developing strategies for conservation, restoration and rational use of water resources. So through the indices: IQA ( Indice de qualidade de águas) Index of water quality, and TC- toxic contamination, reduces conflicts, implements the disciplining of the environmental economy.This study determined the monitoring of sediment and water of Sarandi Stream, so in the samples collected during dry and rainy seasons (2007- 2008) were analyzed heavy metals (Cu, Cd, Cr, Co, Ni, Zn, Pb) and physical-chemical factors (conductivity, solids dissolved, temperature, turbidity). This allowed the determination of Hackanson factors of contamination and Muller Index geoaccumulation, indicating very high contamination in sediments regarding the elements Cr, Cu, and Cd, and high contamination for Pb, Zn, and Mn. The comparison with the indices of water quality- IQA (IGAM - 2006, 2007 and 2008), combined with exploratory data analysis and graphs of correlation between the variables indicated favorable conditions for metals contamination on water and sediment for these metals, besides allowing the identification of its source

  18. Behaviour of heavy water in nuclear reactors of the CEA

    International Nuclear Information System (INIS)

    In the two heavy water reactors of the CEA: Zoe and P-2, we do: A) the supervision of the isotopic composition of the heavy water; B) the supervision of gases released by the decomposition of the heavy water under radiation, and to their recombination; C) periodic analyses of impurities. (M.B.)

  19. Removal of gadolinium nitrate from heavy water

    Energy Technology Data Exchange (ETDEWEB)

    Wilde, E.W.

    2000-03-22

    Work was conducted to develop a cost-effective process to purify 181 55-gallon drums containing spent heavy water moderator (D2O) contaminated with high concentrations of gadolinium nitrate, a chemical used as a neutron poison during former nuclear reactor operations at the Savannah River Site (SRS). These drums also contain low level radioactive contamination, including tritium, which complicates treatment options. Presently, the drums of degraded moderator are being stored on site. It was suggested that a process utilizing biological mechanisms could potentially lower the total cost of heavy water purification by allowing the use of smaller equipment with less product loss and a reduction in the quantity of secondary waste materials produced by the current baseline process (ion exchange).

  20. Water Management Applications of Advanced Precipitation Products

    Science.gov (United States)

    Johnson, L. E.; Braswell, G.; Delaney, C.

    2012-12-01

    Advanced precipitation sensors and numerical models track storms as they occur and forecast the likelihood of heavy rain for time frames ranging from 1 to 8 hours, 1 day, and extended outlooks out to 3 to 7 days. Forecast skill decreases at the extended time frames but the outlooks have been shown to provide "situational awareness" which aids in preparation for flood mitigation and water supply operations. In California the California-Nevada River Forecast Centers and local Weather Forecast Offices provide precipitation products that are widely used to support water management and flood response activities of various kinds. The Hydrometeorology Testbed (HMT) program is being conducted to help advance the science of precipitation tracking and forecasting in support of the NWS. HMT high-resolution products have found applications for other non-federal water management activities as well. This presentation will describe water management applications of HMT advanced precipitation products, and characterization of benefits expected to accrue. Two case examples will be highlighted, 1) reservoir operations for flood control and water supply, and 2) urban stormwater management. Application of advanced precipitation products in support of reservoir operations is a focus of the Sonoma County Water Agency. Examples include: a) interfacing the high-resolution QPE products with a distributed hydrologic model for the Russian-Napa watersheds, b) providing early warning of in-coming storms for flood preparedness and water supply storage operations. For the stormwater case, San Francisco wastewater engineers are developing a plan to deploy high resolution gap-filling radars looking off shore to obtain longer lead times on approaching storms. A 4 to 8 hour lead time would provide opportunity to optimize stormwater capture and treatment operations, and minimize combined sewer overflows into the Bay.ussian River distributed hydrologic model.

  1. Heavy water at Trail, British Columbia

    International Nuclear Information System (INIS)

    Today Canada stands on the threshold of a nuclear renaissance, based on the CANDU reactor family, which depends on heavy water as a moderator and for cooling. Canada has a long history with heavy water, with commercial interests beginning in 1934, a mere two years after its discovery. At one time Canada was the world's largest producer of heavy water. The Second World War stimulated interest in this rather rare substance, such that the worlds largest supply (185 kg) ended up in Canada in 1942 to support nuclear research work at the Montreal Laboratories of the National Research Council. A year later commercial production began at Trail, British Columbia, to support work that later became known as the P-9 project, associated with the Manhattan Project. The Trail plant produced heavy water from 1943 until 1956, when it was shut down. During the war years the project was so secret that Lesslie Thomson, Special Liaison Officer reporting on nuclear matters to C.D. Howe, Minister of Munitions and Supply, was discouraged from visiting Trail operations. Thomson never did visit the Trail facility during the war. In 2005 the remaining large, tall concrete exchange tower was demolished at a cost of about $2.4 million, about the same as it cost to construct the facility about 60 years ago. Thus no physical evidence remains of this historic facility and another important artifact from Canada's nuclear history has disappeared forever. It is planned to place a plaque at the site at some point in the future. (author)

  2. Heavy metals in drinking water: Occurrences, implications, and future needs in developing countries.

    Science.gov (United States)

    Chowdhury, Shakhawat; Mazumder, M A Jafar; Al-Attas, Omar; Husain, Tahir

    2016-11-01

    Heavy metals in drinking water pose a threat to human health. Populations are exposed to heavy metals primarily through water consumption, but few heavy metals can bioaccumulate in the human body (e.g., in lipids and the gastrointestinal system) and may induce cancer and other risks. To date, few thousand publications have reported various aspects of heavy metals in drinking water, including the types and quantities of metals in drinking water, their sources, factors affecting their concentrations at exposure points, human exposure, potential risks, and their removal from drinking water. Many developing countries are faced with the challenge of reducing human exposure to heavy metals, mainly due to their limited economic capacities to use advanced technologies for heavy metal removal. This paper aims to review the state of research on heavy metals in drinking water in developing countries; understand their types and variability, sources, exposure, possible health effects, and removal; and analyze the factors contributing to heavy metals in drinking water. This study identifies the current challenges in developing countries, and future research needs to reduce the levels of heavy metals in drinking water. PMID:27355520

  3. Advanced boiling water reactor

    International Nuclear Information System (INIS)

    In the Boiling Water Reactor (BWR) system, steam generated within the nuclear boiler is sent directly to the main turbine. This direct cycle steam delivery system enables the BWR to have a compact power generation building design. Another feature of the BWR is the inherent safety that results from the negative reactivity coefficient of the steam void in the core. Based on the significant construction and operation experience accumulated on the BWR throughout the world, the ABWR was developed to further improve the BWR characteristics and to achieve higher performance goals. The ABWR adopted 'First of a Kind' type technologies to achieve the desired performance improvements. The Reactor Internal Pump (RIP), Fine Motion Control Rod Drive (FMCRD), Reinforced Concrete Containment Vessel (RCCV), three full divisions of Emergency Core Cooling System (ECCS), integrated digital Instrumentation and Control (I and C), and a high thermal efficiency main steam turbine system were developed and introduced into the ABWR. (author)

  4. Heavy Metal Concentrations in Maltese Potable Water

    Directory of Open Access Journals (Sweden)

    Roberta Bugeja

    2015-05-01

    Full Text Available This study evaluates the levels of aluminum (Al, cadmium (Cd, chromium (Cr, copper (Cu, iron (Fe, lead (Pb, nickel (Ni and zinc (Zn in tap water samples of forty localities from around the Maltese Islands together with their corresponding service supply reservoirs. The heavy metal concentrations obtained indicated that concentrations of the elements were generally below the maximum allowed concentration established by the Maltese legislation. In terms of the Maltese and EU water quality regulations, 17.5% of the localities sampled yielded water that failed the acceptance criteria for a single metal in drinking water. Higher concentrations of some metals were observed in samples obtained at the end of the distribution network, when compared to the concentrations at the source. The observed changes in metal concentrations between the localities’ samples and the corresponding supply reservoirs were significant. The higher metal concentrations obtained in the samples from the localities can be attributed to leaching in the distribution network.

  5. Advances in water resources management

    CERN Document Server

    Yang, Chih; Wang, Mu-Hao

    2016-01-01

    This volume provides in-depth coverage of such topics as multi-reservoir system operation theory and practice, management of aquifer systems connected to streams using semi-analytical models, one-dimensional model of water quality and aquatic ecosystem-ecotoxicology in river systems, environmental and health impacts of hydraulic fracturing and shale gas, bioaugmentation for water resources protection, wastewater renovation by flotation for water pollution control, determination of receiving water’s reaeration coefficient in the presence of salinity for water quality management, sensitivity analysis for stream water quality management, river ice process, and computer-aided mathematical modeling of water properties. This critical volume will serve as a valuable reference work for advanced undergraduate and graduate students, designers of water resources systems, and scientists and researchers. The goals of the Handbook of Environmental Engineering series are: (1) to cover entire environmental fields, includin...

  6. A safety panel for heavy water facility

    International Nuclear Information System (INIS)

    The KUR Heavy Water Facility was renewed for preventive maintenance and for efficient utilization for medical research. This facility is monitored and operated by a new safety control panel installed by the irradiation room. Two types of the control system were employed. One is a traditional wired circuit system. The other is a supervisory, control and data acquisition (SCADA) system which runs on the Windows 3.1 composed of four personal computers connecting to a network called Arcnet. One of them is in a reactor control room and is also connected to Ethernet. (author)

  7. Heavy Water Components Test Reactor Decommissioning

    International Nuclear Information System (INIS)

    The Heavy Water Components Test Reactor (HWCTR) Decommissioning Project was initiated in 2009 as a Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) Removal Action with funding from the American Recovery and Reinvestment Act (ARRA). This paper summarizes the history prior to 2009, the major D and D activities, and final end state of the facility at completion of decommissioning in June 2011. The HWCTR facility was built in 1961, operated from 1962 to 1964, and is located in the northwest quadrant of the Savannah River Site (SRS) approximately three miles from the site boundary. The HWCTR was a pressurized heavy water test reactor used to develop candidate fuel designs for heavy water power reactors. In December of 1964, operations were terminated and the facility was placed in a standby condition as a result of the decision by the U.S. Atomic Energy Commission to redirect research and development work on heavy water power reactors to reactors cooled with organic materials. For about one year, site personnel maintained the facility in a standby status, and then retired the reactor in place. In the early 1990s, DOE began planning to decommission HWCTR. Yet, in the face of new budget constraints, DOE deferred dismantlement and placed HWCTR in an extended surveillance and maintenance mode. The doors of the reactor facility were welded shut to protect workers and discourage intruders. In 2009 the $1.6 billion allocation from the ARRA to SRS for site footprint reduction at SRS reopened the doors to HWCTR - this time for final decommissioning. Alternative studies concluded that the most environmentally safe, cost effective option for final decommissioning was to remove the reactor vessel, both steam generators, and all equipment above grade including the dome. The transfer coffin, originally above grade, was to be placed in the cavity vacated by the reactor vessel and the remaining below grade spaces would be grouted. Once all above equipment

  8. Study of a Heavy-Water Reactor with Boiling Heavy-Water Coolant

    International Nuclear Information System (INIS)

    Among the possible types of heavy-water reactor, those cooled by heavy water would appear to combine the advantages of excellent neutron economy and a well-tried cladding material; this allows optimum utilization of uranium under the present conditions of technology. Placing the reactor, the handling equipment, and the heat exchangers together in a prestressed concrete vessel appreciably simplifies operating problems by reducing the number of hermetic seals in contact with the pressurized heavy water. This arrangement is only effective if a large proportion of the heat transfer is by phase change, so as to keep the amount of coolant to a minimum. The Commissariat à Energie Atomique has made a study of a boiling heavy-water reactor under a co-operation agreement with the Siemens and Sulzer Companies and with the participation of the Socia Company. The paper describes the main features of these projects as well as the main technological problems raised by this design which relate to the thermal insulation of the concrete vessel in the presence of a two-phase fluid; the handling equipment which must function in steam at 300°C; and the accessibility of the exchangers. (author)

  9. Good practices in heavy water reactor operation

    International Nuclear Information System (INIS)

    The value and importance of organizations in the nuclear industry engaged in the collection and analysis of operating experience and best practices has been clearly identified in various IAEA publications and exercises. Both facility safety and operational efficiency can benefit from such information sharing. Such sharing also benefits organizations engaged in the development of new nuclear power plants, as it provides information to assist in optimizing designs to deliver improved safety and power generation performance. In cooperation with Atomic Energy of Canada, Ltd, the IAEA organized the workshop on best practices in Heavy Water Reactor Operation in Toronto, Canada from 16 to 19 September 2008, to assist interested Member States in sharing best practices and to provide a forum for the exchange of information among participating nuclear professionals. This workshop was organized under Technical Cooperation Project INT/4/141, on Status and Prospects of Development for and Applications of Innovative Reactor Concepts for Developing Countries. The workshop participants were experts actively engaged in various aspects of heavy water reactor operation. Participants presented information on activities and practices deemed by them to be best practices in a particular area for consideration by the workshop participants. Presentations by the participants covered a broad range of operational practices, including regulatory aspects, the reduction of occupational dose, performance improvements, and reducing operating and maintenance costs. This publication summarizes the material presented at the workshop, and includes session summaries prepared by the chair of each session and papers submitted by the presenters

  10. Heavy ion irradiation of crystalline water ice

    CERN Document Server

    Dartois, E; Boduch, P; Brunetto, R; Chabot, M; Domaracka, A; Ding, J J; Kamalou, O; Lv, X Y; Rothard, H; da Silveira, E F; Thomas, J C

    2015-01-01

    Under cosmic irradiation, the interstellar water ice mantles evolve towards a compact amorphous state. Crystalline ice amorphisation was previously monitored mainly in the keV to hundreds of keV ion energies. We experimentally investigate heavy ion irradiation amorphisation of crystalline ice, at high energies closer to true cosmic rays, and explore the water-ice sputtering yield. We irradiated thin crystalline ice films with MeV to GeV swift ion beams, produced at the GANIL accelerator. The ice infrared spectral evolution as a function of fluence is monitored with in-situ infrared spectroscopy (induced amorphisation of the initial crystalline state into a compact amorphous phase). The crystalline ice amorphisation cross-section is measured in the high electronic stopping-power range for different temperatures. At large fluence, the ice sputtering is measured on the infrared spectra, and the fitted sputtering-yield dependence, combined with previous measurements, is quadratic over three decades of electronic ...

  11. Advances in water resources engineering

    CERN Document Server

    Wang, Lawrence

    2015-01-01

    The Handbook of Environmental Engineering is a collection of methodologies that study the effects of pollution and waste in their three basic forms: gas, solid, and liquid. A sister volume to Volume 15: Modern Water Resources Engineering, this volume focuses on the theory and analysis of various water resources systems including watershed sediment dynamics and modeling, integrated simulation of interactive surface water and groundwater systems, river channel stabilization with submerged vanes, non-equilibrium sediment transport, reservoir sedimentation, and fluvial processes, minimum energy dissipation rate theory and applications, hydraulic modeling development and application, geophysical methods for assessment of earthen dams, soil erosion on upland areas by rainfall and overland flow, geofluvial modeling methodologies and applications, and an environmental water engineering glossary. This critical volume will serve as a valuable reference work for advanced undergraduate and graduate students, designers of...

  12. Heavy Water Vodka: flawless purity and award winning design

    OpenAIRE

    Storås, Arill; Sandbu, Kristoffer; Eriksen, Sandra Kristine; Isene, Frode

    2008-01-01

    This thesis presents the findings from an explorative research study of the Chinese vodka market. The research has been conducted on behalf of Heavy Water International, a Norwegian vodka producer. Heavy Water International believes that the vodka market in China has considerable growth potential the next 5-10 years, and wants to enter the Chinese vodka market within 2008. Their first goal is to establish a good distributor-connection and create brand awareness. Heavy Water ...

  13. Numerical analysis and optimisation of heavy water upgrading column

    International Nuclear Information System (INIS)

    In the 'Pressurised Heavy Water' type of reactors, heavy water is used both as moderator and coolant. During operation of reactor downgraded heavy water is generated that needs to be upgraded for reuse in the reactor. When the isotopic purity of heavy water becomes less than 99.75%, it is termed as downgraded heavy water. Downgraded heavy water also contains impurity such as corrosion products, dirt, oil etc. Upgradation of downgraded heavy water is normally done in two steps: (i) Purification: In this step downgraded heavy water is first purified to remove corrosion products, dirt, oil, etc. and (ii) Upgradation of heavy water to increase its isotopic purity, this step is carried out by vacuum distillation of downgraded heavy water after purification. This project is aimed at mathematical modelling and numerical simulation of heavy water upgrading column. Modelling and simulation studies of the upgradation column are based on equilibrium stage model to evaluate the effect of feed location, pressure, feed composition, reflux ratio in the packed column for given reboiler and condenser duty of distillation column. State to stage modelling of two-phase two-component flow has constitutes the overall modelling of the column. The governing equations consist of stage-wise species and overall mass continuity and stage-wise energy balance. This results in tridigonal matrix equation for stage liquid fractions for heavy and light water. The stage-wise liquid flow rates and temperatures are governed by stage-wise mass and energy balance. The combined form of the corresponding governing equations, with the incorporation of thermodynamic equation of states, form a system of nonlinear equations. This system have been resolved numerically using modified Newton-Raphson method. A code in the MATLAB platform has been developed by on above numerical procedure. The optimisation of the column operating conditions is to be carried out based on parametric studies and analysis of different

  14. Cost effective water treatment program in Heavy Water Plant (Manuguru)

    International Nuclear Information System (INIS)

    Water treatment technology is in a state of continuous evolution. The increasing urgency to conserve water and reduce pollution has in recent years produced an enormous demand for new chemical treatment programs and technologies. Heavy water plant (Manuguru) uses water as raw material (about 3000 m3/hr) and its treatment and management has benefited the plant in a significant way. It is a fact that if the water treatment is not proper, it can result in deposit formation and corrosion of metals, which can finally leads to production losses. Therefore, before selecting treatment program, complying w.r.t. quality requirements, safety and pollution aspects cost effectiveness shall be examined. The areas where significant benefits are derived, are raw water treatment using polyelectrolyte instead of inorganic coagulant (alum), change over of regenerant of cation exchangers from hydrochloric acid to sulfuric acid and in-house development of cooling water treatment formulation. The advantages and cost effectiveness of these treatments are discussed in detail. Further these treatments has helped the plant in achieving zero discharge and indirectly increased cost reduction of final product (heavy water); the dosage of 3 ppm of polyelectrolyte can replace 90 ppm alum at turbidity level of 300 NTU of raw water which has resulted in cost saving of Rs. 15-20 lakhs in a year beside other advantages; the change over of regenerant from HCl to H2SO4 will result in cost saving of at least Rs.1.4 crore a year besides other advantages; the change over to proprietary formulation to in-house formulation in cooling water treatment has resulted in a saving about Rs.11 lakhs a year. To achieve the above objectives in a sustainable way the performance results are being monitored. (author)

  15. Piping installation for reactor heavy water system

    International Nuclear Information System (INIS)

    Characteristics and main installation steps for the piping of the reactor heavy water loop system were introduced in this paper. According to the system design, equipment accommodation and spot management, main issues with effect on the quality and schedule of pipeline installation were analyzed. Accordingly, some solutions were put forward, which included: work allocation should be made clear in documents; installation preparative such as design checkup and technology communication should be prepared completely; requirements of system cleaning, test items in every experiment, inspection in work and equipment maintenance should be considered in the system design; perfect documents distribution system and stock plan should be built; technology requirements and quality assurance should be claimed in contracts; quality should be controlled by way of external evidence, inspection in manufactory, exterior quality assurance examination, and test during consignment; series of management procedure should be established in detail. (authors)

  16. Heavy water moderated gas-cooled reactors

    International Nuclear Information System (INIS)

    France has based its main effort for the production of nuclear energy on natural Uranium Graphite-moderated gas-cooled reactors, and has a long term programme for fast reactors, but this country is also engaged in the development of heavy water moderated gas-cooled reactors which appear to present the best middle term prospects. The economy of these reactors, as in the case of Graphite, arises from the use of natural or very slightly enriched Uranium; heavy water can take the best advantages of this fuel cycle and moreover offers considerable development potential because of better reactor performances. A prototype plant EL 4 (70 MW) is under construction and is described in detail in another paper. The present one deals with the programme devoted to the development of this reactor type in France. Reasons for selecting this reactor type are given in the first part: advantages and difficulties are underlined. After reviewing the main technological problems and the Research and Development carried out, results already obtained and points still to be confirmed are reported. The construction of EL 4 is an important step of this programme: it will be a significant demonstration of reactor performances and will afford many experimentation opportunities. Now the design of large power reactors is to be considered. Extension and improvements of the mechanical structures used for EL 4 are under study, as well as alternative concepts. The paper gives some data for a large reactor in the present state of technology, as a result from optimization studies. Technical improvements, especially in the field of materials could lead to even more interesting performances. Some prospects are mentioned for the long run. Investment costs and fuel cycles are discussed in the last part. (authors)

  17. Dynamic modelling of Industrial Heavy Water Plant

    International Nuclear Information System (INIS)

    The dynamic behavior of the isotopic enrichment unites of the Industrial Heavy Water Plant, located in Arroyito, Neuquen, Argentina, was modeled and simulated in the present work. Dynamic models of the chemical and isotopic interchange processes existent in the plant, were developed. This served as a base to obtain representative models of the different unit and control systems. The developed models were represented in a modular code for each unit. Each simulator consists of approximately one hundred non-linear-first-order differential equations and some other algebraic equation, which are time resolved by the code. The different simulators allow to change a big number of boundary conditions and the control systems set point for each simulation, so that the program become very versatile. The output of the code allows to see the evolution through time of the variables of interest. An interface which facilitates the use of the first enrichment stage simulator was developed. This interface allows an easy access to generate wished events during the simulation and includes the possibility to plot evolution of the variables involved. The obtained results agree with the expected tendencies. The calculated nominal steady state matches by the manufacturer. The different steady states obtained, agree with previous works. The times and tendencies involved in the transients generated by the program, are in good agreement with the experience obtained at the plant. Based in the obtained results, it is concluded that the characteristic times of the plant are determined by the masses involved in the process. Different characteristics in the system dynamic behavior were generated with the different simulators, and were validated by plant personnel. This work allowed to understand the different process involved in the heavy water manufacture, and to develop a very useful tool for the personnel of the plant. (author). 14 refs., figs., tabs. plant. (author). 14 refs., figs., tabs

  18. Advances in U.S. Heavy Ion Fusion Science

    International Nuclear Information System (INIS)

    During the past two years, the US heavy ion fusion science program has made significant experimental and theoretical progress in simultaneous transverse and longitudinal beam compression, ion-beam-driven warm dense matter targets, high-brightness beam transport, advanced theory and numerical simulations, and heavy ion target physics for fusion. First experiments combining radial and longitudinal compression π of intense ion beams propagating through background plasma resulted in on-axis beam densities increased by 700X at the focal plane. With further improvements planned in 2008, these results enable initial ion beam target experiments in warm dense matter to begin next year. They are assessing how these new techniques apply to higher-gain direct-drive targets for inertial fusion energy

  19. Advanced light water reactor plant

    International Nuclear Information System (INIS)

    For nuclear power to be competitive with the other methods of electrical power generation the economic performance should be significantly improved by increasing the time spent on line generating electricity relative to time spent off-line conducting maintenance and refueling. Maintenance includes planned actions (surveillances) and unplanned actions (corrective maintenance) to respond to component degradation or failure. A methodology is described which is used to resolve maintenance related operating cycle length barriers. Advanced light water nuclear power plant is designed with the purpose to maximize online generating time by increasing operating cycle length. (author)

  20. Advances in BWR water chemistry

    International Nuclear Information System (INIS)

    This paper reviews recent advances in Boiling Water Reactor (BWR) water chemistry control with examples of plant experiences at U.S. designed BWRs. Water chemistry advances provide some of the most effective methods for mitigating materials degradation, reducing fuel performance concerns and lowering radiation fields. Mitigation of stress corrosion cracking (SCC) of materials remains a high priority and improved techniques that have been demonstrated in BWRs will be reviewed, specifically hydrogen injection combined with noble metal chemical addition (NMCA) and the newer on-line noble metal application process (OLNC). Hydrogen injection performance, an important part of SCC mitigation, will also be reviewed for the BWR fleet, highlighting system improvements that have enabled earlier injection of hydrogen including the potential for hydrogen injection during plant startup. Water chemistry has been significantly improved by the application of pre-filtration and optimized use of ion exchange resins in the CP (condensate polishing) and reactor water cleanup (RWCU) systems. EPRI has monitored and supported water treatment improvements to meet water chemistry goals as outlined in the EPRI BWR Water Chemistry Guidelines, particularly those for SCC mitigation of reactor internals and piping, minimization of fuel risk due to corrosion and crud deposits and chemistry control for radiation field reduction. In recent years, a significant reduction has occurred in feedwater corrosion product input, particularly iron. A large percentage of plants are now reporting <0.1 ppb feedwater iron. The impacts to plant operation and chemistry of lower feedwater iron will be explored. Depleted zinc addition is widely practiced across the fleet and the enhanced focus on radiation reduction continues to emphasize the importance of controlling radiation source term. In addition, shutdown chemistry control is necessary to avoid excessive release of activated corrosion products from fuel

  1. Hybrid and electric advanced vehicle systems (heavy) simulation

    Science.gov (United States)

    Hammond, R. A.; Mcgehee, R. K.

    1981-01-01

    A computer program to simulate hybrid and electric advanced vehicle systems (HEAVY) is described. It is intended for use early in the design process: concept evaluation, alternative comparison, preliminary design, control and management strategy development, component sizing, and sensitivity studies. It allows the designer to quickly, conveniently, and economically predict the performance of a proposed drive train. The user defines the system to be simulated using a library of predefined component models that may be connected to represent a wide variety of propulsion systems. The development of three models are discussed as examples.

  2. Decontamination of the heavy water system of the RA reactor

    International Nuclear Information System (INIS)

    The heavy water system of the RA reactor was decontaminated of 60Co. The solution used for decontamination was 7% H3PO4 and 3% CrO3. The decontamination factor ranged from 10 to 100. From the results the distribution of 60Co in the heavy water, and on stainless and aluminium parts was determined (author)

  3. Natural uranium lattice in heavy water

    International Nuclear Information System (INIS)

    A group of Laplacian determinations have been made under critical running conditions in a heavy water pile specially constructed to this end using either complete lattices or samples of lattices employing a two-zone method. The experimental equipment is briefly described: it has been devised to allow rapid modifications of the charge. The methods of measurement employed are also summarily described one operates either by flux charts in the case of lattices which are then used as references, or by progressive replacement of the bars by concentric rings and measurements of the reactivity. In this case, one attempts to obtain the difference between the material laplacian of the central unknown lattice and that of the reference lattice. The method has been specially develop ped to give precision. Results of Laplacian measurements for all these lattice types are presented, allowing the construction of a set of curves as a function of the separation. Various other effects have also been measured: the equivalent reactivity of a mm of water - anisotropy - temperature effect, etc. However in this first attack on the problem, the measurement of a large variety of Laplacian has been carried out, rather than careful measurements in particular cases. It is in this spirit that the interpretation of the results has been made. As a large number of very complex phenomena still escape the possibilities of the calculation, it is considered that a certain number of adjustments are necessary; now these can only give the desired efficiency in forecasting results if they refer to a sufficiently great number of experimental data. It is necessary then to connect the measurements closely on with the other whilst, at the same time, subdividing them according to logically deduced formulae. The principal source of trouble has been that of coherence. The rules governing the calculations employed in the interpretation of the data are given. In the first instance simple formula are used: first of

  4. Safety systems of heavy water reactors and small power reactors

    International Nuclear Information System (INIS)

    After introductional descriptions of heavy water reactors and natural circulation boiling water reactors the safety philosophy and safety systems like ECCS, residual heat removal, protection systems etc., are described. (RW)

  5. Method and apparatus for enrichment or upgrading heavy water

    International Nuclear Information System (INIS)

    A method and apparatus for upgrading and final enrichment of heavy water are described, comprising means for contacting partially enriched heavy water feed in a catalyst column with hydrogen gas (essentially D2) originating in an electrolysis cell so as to enrich the feed water with deuterium extracted from the electrolytic hydrogen gas and means for passing the deuterium enriched water to the electrolysis cell. (author)

  6. Seismic re-evaluation of Heavy Water Plant, Kota

    International Nuclear Information System (INIS)

    This report deals with seismic re-evaluation of Heavy Water Plant, Kota. Heavy Water Plant, Kota handles considerable amount of H2S gas, which is very toxic. During the original design stage as per IS 1893-1966 seismic coefficient for zone-I was zero. Therefore earthquake and its effects were not considered while designing the heavy water plant structures. However as per IS 1893 (1984) the seismic coefficient for zone-I is 0.01 g. Hence seismic re-evaluation of various structures of the heavy water plant is carried out. Analysis of the heavy water plant structures was carried out for self weight, equipment load and earthquake load. Pressure loading was also considered in case of H2S storage tanks. Soil structure interaction effect was considered in the analysis. The combined stresses in the structures due to earthquake and dead load were checked with the allowable stresses. (author)

  7. Production of heavy water in France

    International Nuclear Information System (INIS)

    Since 1958, studies relating to heavy water production have covered several processes. Each one has been examined to a greater or lesser degree and attention has finally been concentrated on the isotopic exchanges between hydrogen sulphide and water and between ammonia and synthesis gas, the pilot experiment having shown that hydrogen distillation, although technologically satisfactory, was not competitive. NH3 synthesis gas exchange process; 1) Research was continued and led to the decision to build a production unit, devoted also to the synthesis of ammonia. The process essentially depends on the source of the synthesis gas; the use of a H2O/H2 exchange, which could make it independent, has in fact been rejected for economic reasons. Amongst the various possible designs for the process, the one temperature system was chosen, in spite of certain technological problems, because of it provides: a high enrichment with a reduced number of contact devices. These have now been perfected after large-scale pilot tests. The original industrial experiment to be set in operation will supply useful information for second generation plants, whether they use the one temperature lay out again or whether they adopt the two temperature system. H2S-H2O exchange process. The pilot plant, described in 1958, has been used for a systematic study of corrosion. It was possible to proceed to preliminary specifications of plants, with 2 or 3 H2S - H2O stages exchange for primary enrichment. They final stage beyond a 10 to 20 p.100 D2O concentration being carried out by the distillation of water. Various heat exchange systems have been studied in detail and it was concluded that choices, as for instance the one of optimum division of the cascade, were eventually to be made according to the particular economic conditions of creation at the chosen location of the plant. (author)

  8. An optical dosimeter for monitoring heavy metal ions in water

    Science.gov (United States)

    Mignani, Anna G.; Regan, Fiona; Leamy, D.; Mencaglia, A. A.; Ciaccheri, L.

    2005-05-01

    This work presents an optochemical dosimeter for determining and discriminating nickel, copper, and cobalt ions in water that can be used as an early warning system for water pollution. An inexpensive fiber optic spectrophotometer monitors the sensor's spectral behavior under exposure to water solutions of heavy metal ions in the 1-10 mg/l concentration range. The Principal Component Analysis (PCA) method quantitatively determines the heavy metals and discriminates their type and combination.

  9. Best practices in management of heavy water and tritium

    International Nuclear Information System (INIS)

    The heavy water inventory of a typical HWR constitutes about 12% of the capital cost of the HWR. The typical tritium production in a single unit HWR is about 2 x 106 Ci/y.1 Heavy water and tritium control are important aspects of HWR operation, and this involves people, procedures, equipment and heavy water and tritium separation systems. Station personnel are trained to understand the importance of heavy water management and the economics and environmental impact of tritiated heavy water losses. The tritium and heavy water losses from a HWR are both airborne and waterborne in nature. Tritium is of particular concern in the HWR industry given the nature of heavy water reactors to build up high levels of tritium over time. Recent increased interest from regulators and the public has led more HWR utilities to pay increasing attention to occupational safety and environmental emissions of tritium at their power stations. As competing reactor technologies improve, a simple and economic means for tritium removal from heavy water in HWRs is essential for the long- term attractiveness of HWR technology. Tritium safety, occupational and environmental issues are of central importance in HWR licensing and operation. Building upon GE's extensive operational experience in tritium management in HWR reactors and its own tritium handling facility, GE2 has developed a large-scale diffusion-based isotope separation process as an alternative to conventional cryogenic distillation. Having a tritium inventory an order of magnitude lower than conventional cryogenic distillation, this process is very attractive for heavy water detritiation, applicable to single and multi-unit HWR and research reactors. Additionally, the new process has significant benefits to an operating HWR utility such as reducing environmental emissions and significantly lowering reactor vault tritium MPC(a) levels to a point where station capacity factors can be improved by shorter outages - representing best

  10. The Advanced Light Water Reactor

    International Nuclear Information System (INIS)

    The U. S. Advanced Light Water Reactor Program is a forward-looking program designed to produce viable nuclear generating system candidates to meet the very real, and perhaps imminent, need for new power generation capacity in the U. S. and around the world. The ALRR Program is an opportunity to move ahead with confidence, to confront problems today which must be confronted if the U. S. electrical utilities are to continue to meet their commitment to provide safe, reliable, economical electrical power to the nation in the years ahead. Light water reactor technology is today playing a vital role in the production of electricity to meet the world's needs. At present about 13% of the world's electricity is supplied by nuclear power plants, most of those light water reactors. Nevertheless, there is a clear need for expanded use of nuclear generation. Here in Korea and elsewhere in Asia, demand for electricity has continued to increase at a very high rate. In the United States demand growth has been more moderate, but a large number of existing stations will be ready for replacement in the next two decades, and all countries face the problem of dwindling fuel supplies and growing environmental impact of fossil-fired power plants. Despite the evident need for expanded nuclear generation capacity in the United States, there have been no new plants ordered in the past ten years and at present there are no immediate prospects for new plant orders. Concerns about safety, the high cost of recent nuclear stations, and the current excess of electrical generation capacity in the United States, have combined to interrupt completely the growth of this vital power supply system

  11. Process for the preparation of ammonia and heavy water

    International Nuclear Information System (INIS)

    A process for the production of ammonia and heavy water comprises the steps of enriching a flow of water with deuterium in a monothermal isotropic process; supplying a first portion of the deuterium-enriched water to a heavy water preparation plant to produce heavy water and hydrogen; storing a second portion of the deuterium-enriched water substantially without interruption during the colder half of a year; electrolytically dissociating the stored deuterium-enriched water substantially without interruption during the wamer half of a year to form hydrogen; storing a portion of the electrolytically-produced hydrogen during said warmer half of a year while supplying the remainder to a synthesis circuit of a synthesizing plant and subsequently supplying the stored hydrogen to the synthesis circuit during said colder half of a year; removing some of the synthesis gas mixture from the synthesis circuit of the synthesizing plant; burning the removed synthesis gas mixture with air to produce a mixture consisting mainly of water and nitrogen; thereafter condensing and separating the water from the mixture of water and nitrogen; supplying the nitrogen of the mixture of water and nitrogen, the hydrogen from the heavy water preparation plant and the electrolytically-produced hydrogen to the synthesis circuit of the synthesizing plant to produce ammonia; and collecting deuterium-depleted water resulting from said burning step and feeding the collected deuterium-depleted water into the monothermal process

  12. Magnetic filtration of heavy metals containing waters

    International Nuclear Information System (INIS)

    The high-intensity magnetic separation is applied above all in the beneficiation of fine-grained weakly magnetic ores, but also in the treatment of industrial, especially metallurgical and mining waters as well as of wastewaters from nuclear power stations. Similarly, it can be used in the field of geothermal energy supply and gases filtration. The magnetic separation or filtration respectively, directly enables the treatment of waters contaminated by solid ferromagnetic and paramagnetic particles. The magnetic filtration can remove heavy metals ions and even the oil substances by means of magnetic sorbents or special additives. The filtration of solid magnetic particles can be carried out in matrix-less and matrix separators. On the basis of mathematical description of particles dynamics and hydrodynamic conditions of suspension flow which resulted in the determination of geometrical parameters of separating zone the design of matrix-less magnetic separator was carried out. A strong, high-intensity magnetic field was created by means of a superconductive magnetic circuit. It was found out that for the achievement of optimal technological parameters during the magnetic separation of solid particles with grain size under 40 mm, the maximal solids concentration is to be 200 g/L. The design of matrix parameters and selection of inductive filling resides in theoretical considerations as well as in experimental works. Under laboratory condition the influence of following parameters on magnetic filtration process have been observed: the diameter of inductive ferromagnetic balls, the thickness of filtration layer, the intensity of magnetic field, the flow velocity of suspension, the density of suspension, the grain size of solids and the temperature of suspension. It was found that a spatial arrangement of inductive bodies in filtration layer influences not only the velocity of suspension flow but also a room size for catching of magnetic particles. The acting of magnetic

  13. SPECIATION OF HEAVY METALS AT WATER-SEDIMENT INTERFACE

    Directory of Open Access Journals (Sweden)

    Chiara Ferronato

    2013-09-01

    Full Text Available The objective of the study was to understand the equilibrium relationship between the heavy metals concentrations in superficial water and pore water. At  water-sediment interface, the equilibrium rapidly changed and it is influenced by chemico-physical parameters of aquatic ecosystems. The hydraulic safety of Bologna plain (North Italy depends on network of artificial canals and they are related with natural rivers of Reno basin (Reno river and its tributaries. The natural and artificial water courses flowed in agricultural, urban and industrial land. The heavy metals concentration in water and sediment discriminated the human pressure on the land and their spatial distribution in sediment could predict the hazard of pollution in aquatic ecosystems. We compared the heavy metals concentrations in pore water and superficial water determined in natural rivers and artificial canals, and more pollution in artificial canals than natural rivers was found. Furthermore, the coefficient of partition (log Kd between water and sediments was calculated to evaluate the bioavailability of heavy metals adsorbed on the sediments. The heavy metals extracted in deionised water at equilibrium after 16 h showed higher concentrations than those determined directly on water samples.

  14. Alkali metal and ammonium chlorides in water and heavy water (binary systems)

    CERN Document Server

    Cohen-Adad, R

    1991-01-01

    This volume surveys the data available in the literature for solid-fluid solubility equilibria plus selected solid-liquid-vapour equilibria, for binary systems containing alkali and ammonium chlorides in water or heavy water. Solubilities covered are lithium chloride, sodium chloride, potassium chloride, rubidium chloride, caesium chloride and ammonium chloride in water and heavy water.

  15. Manufacturing opportunities in the Canadian CANDU and heavy water programs

    International Nuclear Information System (INIS)

    The volume of business available to Canadian manufacturers of CANDU power plant and heavy water plant components is analyzed over about the next 10 years. Implications of exported nuclear technology and plants are explored. (E.C.B.)

  16. Program for steam table of heavy water for Thermohydrodynamic Analysis

    International Nuclear Information System (INIS)

    On the basis of open literatures about thermal properties of heavy water, a computer code has been developed for steam tables of heavy water by means of the multi-dimensional Newton's method. Two independent variables of the tables are settled to be pressure and enthalpy as well as pressure and temperature in order to apply the code to the Thermohydrodynamic Analysis and order simple thermal calculations. (author)

  17. Phytoremediation of heavy metal polluted soil and water in Vietnam

    OpenAIRE

    Bui, Thi Kim Anh; Dang, Dinh Kim; Nguyen, Trung Kien; Nguyen, Ngoc Minh,; Nguyen, Quang Trung; Nguyen, Hong Chuyen

    2015-01-01

    Phytoremediation has been intensively studied during the past decade due to its cost-effectiveness and environmental harmonies. Most of the studies on treatment of heavy metal pollution in soil and water by plant species have been done in developed countries but are limited in Vietnam. In this study, we presented some research results of phytoremediation of polluted soils and water with heavy metals that were done by Institute of Environmental Technology for several last years. For treatment ...

  18. Heavy water wastes purification from tritium by CECE process

    Energy Technology Data Exchange (ETDEWEB)

    Alekseev, I.A.; Bondarenko, S.D.; Fedorchenko, O.A.; Vasyanina, T.V.; Konoplev, K.A.; Arkhipov, E.A. [Petersburg Nuclear Physics Institute, Leningrad (Russian Federation); Uborsky, V.V. [JSC ' DOL' , Moscow (Russian Federation)

    2007-07-01

    Future fusion reactors require Isotope Separation System for tritium extracting mainly from light water. Nuclear reactors moderated by heavy water also require upgrading facility to maintain deuterium concentration in water and facility for tritium recovery. The problems of tritium removal from heavy and light water and upgrading of tritiated heavy water wastes are issue of the day as before. To date the combined electrolysis catalytic exchange (CECE) process utilizing wetproofed catalyst is the most attractive one for extracting tritium from water due to its high separation factors and near-ambient operating conditions. The experimental industrial plant has been built in PNPI for the development of the CECE technology for hydrogen isotope separation. The process uses a LPCE column and electrolysis cells to convert water to hydrogen. The plant has been in operation about 10 years. In parallel with a development of CECE process for hydrogen isotope separation the plant is used for reprocessing tritium heavy water waste. Processing waste with the content of {proportional_to} 47 % of heavy hydrogen and 108 Bq/kg of tritium, the plant produces 99.85-99.995% heavy water and deuterium gas for science and industry. Owing to industrial demands for heavy water with reduced tritium content, the plant was modified and additional equipment and procedures were put in place to operate in the detritiation mode. After prolonged operation campaigns it was decided to update the plant with an additional separation column connected with existing equipment. Now the main parts of plant are two 100-diameter exchange columns of 7.5 m and 6.9 m overall height correspondingly, alkaline electrolytic cells. The columns are filled with alternating layers of wetproofed catalyst developed by Mendeleev University and stainless steel spiral-prismatic packing. The first column consists of five separation sections connected through a distributor of liquid, the second column consists of three

  19. Heavy water wastes purification from tritium by CECE process

    International Nuclear Information System (INIS)

    Future fusion reactors require Isotope Separation System for tritium extracting mainly from light water. Nuclear reactors moderated by heavy water also require upgrading facility to maintain deuterium concentration in water and facility for tritium recovery. The problems of tritium removal from heavy and light water and upgrading of tritiated heavy water wastes are issue of the day as before. To date the combined electrolysis catalytic exchange (CECE) process utilizing wetproofed catalyst is the most attractive one for extracting tritium from water due to its high separation factors and near-ambient operating conditions. The experimental industrial plant has been built in PNPI for the development of the CECE technology for hydrogen isotope separation. The process uses a LPCE column and electrolysis cells to convert water to hydrogen. The plant has been in operation about 10 years. In parallel with a development of CECE process for hydrogen isotope separation the plant is used for reprocessing tritium heavy water waste. Processing waste with the content of ∝ 47 % of heavy hydrogen and 108 Bq/kg of tritium, the plant produces 99.85-99.995% heavy water and deuterium gas for science and industry. Owing to industrial demands for heavy water with reduced tritium content, the plant was modified and additional equipment and procedures were put in place to operate in the detritiation mode. After prolonged operation campaigns it was decided to update the plant with an additional separation column connected with existing equipment. Now the main parts of plant are two 100-diameter exchange columns of 7.5 m and 6.9 m overall height correspondingly, alkaline electrolytic cells. The columns are filled with alternating layers of wetproofed catalyst developed by Mendeleev University and stainless steel spiral-prismatic packing. The first column consists of five separation sections connected through a distributor of liquid, the second column consists of three separation sections

  20. Analysis of thorium/U-233 lattices and cores in a breeder/burner heavy water reactor

    International Nuclear Information System (INIS)

    Due to the inevitable dwindling of uranium resources, advanced fuel cycles in the current generation of reactors stand to be of great benefit in the future. Heavy water moderated reactors have much potential to make use of thorium, a currently unexploited resource. Core fuelling configurations of a Heavy Water Reactor based on the self-sufficient thorium fuel cycle were simulated using the DRAGON and DONJON reactor physics codes. Three heterogeneously fuelled reactors and one homogeneously fuelled reactor were studied. (author)

  1. Predicted characteristics of PTR with heavy water thermal column

    International Nuclear Information System (INIS)

    The critical masses, the fast and slow neutron flux distributions, and the fast and slow adjoint functions are calculated for PTR having heavy water thermal columns of 7 different diameters, 3 with a central light water column. The sensitivities of PTR to fissionable samples, and absorbers as well as the mean lifetimes of the neutrons are determined for the different size thermal columns. (author)

  2. Near well simulation of heavy oil reservoir with water drive

    OpenAIRE

    Ediriweera, Mahesh Priyankara

    2015-01-01

    The Depletion of oil production and the low recovery rate are major challenges faced in oil production at Norwegian continental self. Several studies have shown that considerable amount of oil still remains after the well shutdown. Heavy oil reservoirs occupy more than two third of globally oil reserves. Therefore, extensive studies are undergone to optimize the oil recovery in heavy oil reservoirs. Water flooding and Enhanced Oil Recovery (EOR) methods are successfully implemente...

  3. Technological design of heavy water production facilities

    International Nuclear Information System (INIS)

    The paper deals with the mathematical models and the computational programs utilized in the design of installations for the deuterium separation by isotopic exchange in water-hydrogen sulfide system, by water isotopic distillation and by hydrogen isotopic distillation

  4. Safety and hazard control in Heavy Water Plants

    International Nuclear Information System (INIS)

    Heavy Water Plants are constituent units of Heavy Water Board under Department of Atomic Energy. Heavy water, a compound of deuterium (an isotope of hydrogen) and oxygen is used as a moderator and coolant in Pressurised Heavy Water based nuclear reactors. Heavy Water Plants at Baroda, Tuticorin, Thal and Hazira employ Mono-thermal Ammonia Hydrogen Chemical Exchange Process for production of heavy water. Raw materials used in this process are Deuterium bearing hydrogen in the form of synthesis gas (a mixture of hydrogen and nitrogen in the ratio of 3:1) produced in the adjacent fertilizer plants. HWPs at Kota and Manuguru employ bi thermal Water-Hydrogen Sulphide Chemical Exchange Process. HWPs handle hazardous chemicals such as Hydrogen, Hydrogen sulphide, Ammonia, Naphtha, Hexane, Potassium, Potassium Amide etc. The operating pressure and temperature are varying from vacuum to 260 kg/cm2(g) and -185 deg C to 900 deg C respectively. Our commitment towards safety and health of human resources, materials and environment have paid rich dividends to HWPs. HWPs have achieved many records and received many awards including 4414 days operation (twelve years of operation) continuously without any lost time injury, several awards including Industrial Safety Award from AERB (Atomic Energy Regulatory Board), highest national award in safety among chemical industries - Sarvashresta Suraksha Puraskar India consecutively two years and Shresta Suraksha Puraskar for five years from NSC (National Safety Council), India. The high standard of performance could be achieved mainly due to self discipline, skilled operation of the plants with improved work culture, Quality Management System ISO 9001, Environment Management System ISO 14001 and Occupational Health and Safety Management System IS 18001, adopted in HWPs besides well defined responsibility and authority in HWB and HWPs

  5. The Bare Critical Assembly of Natural Uranium and Heavy Water

    International Nuclear Information System (INIS)

    The first reactor built in Yugoslavia was the bare zero energy heavy water and natural uranium assembly at the Boris Kidric Institute of Nuclear Sciences, Belgrade. The reactor went critical on April 29, 1958. The possession of four tons of natural uranium metal and the temporary availability of seven tons of heavy water encouraged the staff of the Institute to build a critical assembly. A critical assembly was chosen, rather than high flux reactor, because the heavy water was available only temporarily. Besides, a 10 MW, enriched uranium, research reactor is being built at the same Institute and should be ready for operation late this year. It was supposed that the zero energy reactor would provide experience in carrying out critical experiments, operational experience with nuclear reactors, and the possibility for an extensive program in reactor physics. (author)

  6. EVALUATION OF HEAVY METAL IN COASTAL WATER AT KELANTAN

    Directory of Open Access Journals (Sweden)

    Rizki Wannahari

    2013-01-01

    Full Text Available Five sites were selected representing the studied sites of the coastal water in Kelantan, Malaysia during 1996 until May 2012. These selected sites are the popular beaches in Kelantan which are Sri Tujuh Beach (STB located in Tumpat region, Cahaya Bulan Beach (PCB and Sabak Beach (SB in Kota Bharu region, Irama Beach (PI in Bachok region and Bisikan Bayu Beach (PBB in Pasir Putih region. In other to identify the quality of coastal water in this five popular coasts along Kelantan, study of heavy metals contamination in coastal water has been done. Evaluation of heavy metal contamination in Kelantan coastal water has doing by combine the data from Department of Environment (DOE Malaysia and the data was got from this research. There are four types of heavy metal concentration has evaluated in this research; Cadmium (Cd, Cupper (Cu, Lead (Pb and Chromium (Cr. From this evaluation, we can see the fluctuation of concentration the four type heavy metal (Cd, Cu, Pb, Cr from 1996 until May 2012. Most of the year, the concentration of heavy metal is between the range of Malaysia marine quality standard except for Lead. Lead was proven to be the highest concentration pollutant in the five beaches in certain time and also exceed the Malaysia marine standard.

  7. Combined Electrolysis and Catalytic Exchange (CECE) upgraders - an alternative to Water Distillation (DW) heavy water upgraders

    International Nuclear Information System (INIS)

    All operating CANDU stations are equipped with Water Distillation (DW) systems for heavy water upgrading. An alternative process, Combined Electrolysis and Catalytic Exchange (CECE), is being considered for use in future CANDU stations. The CECE process has several operating advantages over DW systems, including lower emissions and heavy water losses. Changes in nuclear standards may change seismic requirements and classification of upgrader systems. These changes will likely increase the cost of heavy water upgraders, but the cost increase will be smaller for a CECE upgrader. Research at Chalk River Labs has identified materials for use in the CECE process that will not chemically or mechanically degrade when exposed to highly tritiated water. (author)

  8. Size fractionation of heavy metals in highway runoff waters

    OpenAIRE

    BECHET, Béatrice; Durin, Bertrand; Legret, Michel; Le Cloirec, Pierre

    2010-01-01

    Highway runoff waters may contain pollutants that have accumulated on the carriageway. Numerous field surveys have demonstrated that heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) are common pollutants in highway runoff waters that degrade the quality of natural water bodies [16]. These hazardous pollutants have been found to be attached to particles, especially finer particles than 100 μm, usually quantified by dissolved, suspended and settleable solids measurements [7]. Clay minerals, very fine...

  9. SPECIATION OF HEAVY METALS AT WATER-SEDIMENT INTERFACE

    OpenAIRE

    Chiara Ferronato; Livia Vittori Antisari; Monica Marianna Modesto; Gilmo Vianello

    2013-01-01

    The objective of the study was to understand the equilibrium relationship between the heavy metals concentrations in superficial water and pore water. At  water-sediment interface, the equilibrium rapidly changed and it is influenced by chemico-physical parameters of aquatic ecosystems. The hydraulic safety of Bologna plain (North Italy) depends on network of artificial canals and they are related with natural rivers of Reno basin (Reno river and its tributaries). The natural and artificial w...

  10. Heavy water detritiation to support CANDU station maintenance activities

    International Nuclear Information System (INIS)

    Heavy water and tritium control are important aspects of CANDU operation and have a major impact on station maintenance activities. Station personnel are trained to understand the importance of heavy water management and the economics and environmental impact of tritiated heavy water losses. This paper discusses new GE technology that can now make a major improvement in CANDU maintenance activities through significant reductions in station tritium levels. Tritium is of particular concern in the CANDU industry given the nature of heavy water reactors to build up high levels of tritium over time. High tritium levels in the reactor vault significantly slow down maintenance activities in the reactor vault due to the requirement for personnel protective equipment, including breathing apparatus and cumbersome plastic air suits. The difficulties increase as reactors age and tritium levels increase. Building upon GE's extensive operational experience in tritium management in CANDU reactors and its own tritium handling facility, GE. has developed a new large-scale diffusion based isotope separation process as an alternative to conventional cryogenic distillation. Having a tritium inventory an order of magnitude lower than conventional cryogenic distillation, this process is very attractive for heavy water detritiation, and applicable to single and multi-unit CANDU stations. This new process can now provide a step change reduction in CANDU heavy water tritium levels resulting in reduced environmental emissions and lowering reactor vault tritium MPC(a) levels. Reactor vault tritium can be reduced sufficiently for maintenance activities to be done without plastic suits, leading to shorter outages, improved station capacity factors, and improved station economics. (author)

  11. Analysis of Gamma Activity of Heavy Water at RB Reactor

    International Nuclear Information System (INIS)

    The RB experimental nuclear reactor still works with heavy water obtained in 1959 from the former USSR. Gamma activity of the heavy water was periodically controlled during the past time. In this experiment, measurements were carried out with two samples: D2O taken from the RB reactor and D2O that has been used in the reactor. Two germanium spectrometers were used as detectors. Gamma spectra data were evaluated manually and using several computer codes. results of the experiment show that gamma activity D2O of RB reactor is at the level of background in the Vinca Institute, without contamination with fission products. (author)

  12. Distributed systems in the heavy water plant environment

    International Nuclear Information System (INIS)

    This paper describes the data acquisition system on the Atomic Energy of Canada Limited, Glace Bay heavy water plant. After four years of successfull operation and frequent changes during this period in response to changing requirements the availability of the system has stabilized at 99 percent. The plant support group carry out all hardware and software maintenance. Based on the experience with this system consideration is being given to a computer control system for the plant. A distributed control system structure appears to be well suited to the heavy water plant requirements. (auth)

  13. Energy conservation and management strategies in Heavy Water Plants

    International Nuclear Information System (INIS)

    In the competitive industrial environment it is essential that cost of the product is kept at the minimum possible. Energy conservation is an important aspect in achieving this as energy is one of the key recourses for growth and survival of industry. The process of heavy water production being very complex and energy intensive, Heavy Water board has given a focussed attention for initiating various measures for reducing the specific energy consumption in all the plants. The initiative resulted in substantial reduction in specific energy consumption and brought in savings in cost. The cumulative reduction of specific energy consumption has been over 30% over the last seven years and the total savings for the last three years on account of the same has been about Rs. 190 crore. The paper describes the strategies adopted in the heavy water plants for effecting the above achievements. The paper covers the details of some of the energy saving schemes carried out at different heavy water plants through case studies. The case studies of schemes implemented at HWPs are general in nature and is applicable for any other industry. The case studies cover the modifications with re-optimisation of the process parameters, improvements effected in utility units like refrigeration and cooling water systems, improvements in captive power plant cycle and improved recycle scheme for water leading to reduced consumptions. The paper also mentions the innovative ammonia absorption refrigeration with improved coefficient of performance and HWB's efforts in development of the system as an integrated unit of the ammonia water deuterium exchange process for heavy water production. HWB also has taken up R and D on various other schemes for improvements in energy consumption for future activities covering utilisation of low grade energy for generation of refrigeration. (author)

  14. Advances in light water reactor technologies

    CERN Document Server

    Saito, Takehiko; Ishiwatari, Yuki; Oka, Yoshiaki

    2010-01-01

    ""Advances in Light Water Reactor Technologies"" focuses on the design and analysis of advanced nuclear power reactors. This volume provides readers with thorough descriptions of the general characteristics of various advanced light water reactors currently being developed worldwide. Safety, design, development and maintenance of these reactors is the main focus, with key technologies like full MOX core design, next-generation digital I&C systems and seismic design and evaluation described at length. This book is ideal for researchers and engineers working in nuclear power that are interested

  15. Utilizing heavy metal-laden water hyacinth biomass in vermicomposting.

    Science.gov (United States)

    Tereshchenko, Natalya N; Akimova, Elena E; Pisarchuk, Anna D; Yunusova, Tatyana V; Minaeva, Oksana M

    2015-05-01

    We studied the efficiency of water treatment by water hyacinth (Eichhornia crassipes) from heavy metals (Zn, Cd, Pb, Cu), as well as a possibility of using water hyacinth biomass obtained during treatment for vermicomposting by Eisenia fetida and the vermicompost quality in a model experiment. The results showed that the concentration of heavy metals in the trials with water hyacinth decreased within 35 days. We introduced water hyacinth biomass to the organic substrate for vermicomposting, which promoted a significant weight gain of earthworms and growth in their number, as well as a 1.5- to 3-fold increase in coprolite production. In the trial with 40 % of Eichhornia biomass in the mixture, we observed a 26-fold increase in the number and a 16-fold weight gain of big mature individuals with clitellum; an increase in the number of small individuals 40 times and in the number of cocoons 140 times, as compared to the initial substrate. The utilization of water hyacinth biomass containing heavy metals in the mixture led to a 10-fold increase in the number of adult individuals and cocoons, which was higher than in control. We found out that adding 10 % of Eichhornia biomass to the initial mixture affected slightly the number of microorganisms and their species diversity in the vermicompost. Adding Eichhornia biomass with heavy metals reduced the total number of microorganisms and sharply diminished their species diversity. In all trials, adding water hyacinth in the mixture for vermicomposting had a positive impact on wheat biometric parameters in a 14-day laboratory experiment, even in the trial with heavy metals. PMID:25501861

  16. Safety system in a heavy water detritiation plant

    International Nuclear Information System (INIS)

    In a CANDU 6 type reactor a quantity of 55·1015Bq/year of tritium is generated, 95% being in the D2O moderator which can achieve a radioactivity of 2.5-3.5·1012Bq/kg. Tritium in heavy water contributes with 30-50% to the doses received by operation personnel and up to 20% to the radioactivity released in the environment. The large quantity of heavy water used in this type of reactors (500 tones) make storage very difficult, especially for environment. The extraction of tritium from tritiated heavy water of CANDU reactors solve the following problems: the radiation level in the operation area, the costs of maintenance and repair reduction due to reduction of personnel protection measures, the increase of NPP utilisation factor by shutdown time reduction for maintenance and repair, use the extracted tritium for fusion reactors and not for the last, lower costs and risk for storage heavy water waste. Heavy water detritiation methods, which currently are used in the industrial or experimental plant, are based on catalytic isotope exchange or electrolysis followed cryogenic distillation or permeation. The technology developed at Institute of Cryogenics and Isotope Separation is based upon catalytic exchange between tritiated water and deuterium, followed by cryogenic distillation of hydrogen isotopes. The nature of the fluids that are processed in detritiation requires the operation of the plant in safety conditions. The paper presents the safety system solution chose in order to solve this task, as well as a simulation of an incident and safety system response. The application software is using LabView platform that is specialised on control and factory automation applications. (author)

  17. Selected bibliography on deuterium isotope effects and heavy water

    International Nuclear Information System (INIS)

    In recent years, there has been a great deal of interest in using deuterium and heavy water not only in nuclear industry but also in various fields of basic as well as applied research in physics, chemistry and biology. As a result, the literature is being enriched with a large number of research papers and technical reports published each year. Thus, to enable the scientists to have an easy reference to these works, an endeavour has been made in this selected bibliography, to enlist the publications related to these fields. Since the interest is concerned mainly with heavy water production processes, deuterium isotope effects etc., several aspects (e.g. nuclear) of deuterium have not been covered here. The material in this bibliography which cites 2388 references has been classified under six broad headings, viz. (1) Production of heavy water, (2) Study of deuterium isotope effects, (3) Analysis and Properties of heavy water, (4) Laser Separation of deuterium, (5) Isotopic exchange reactions, and (6) Miscellaneous. The sources of information used for this compilation are chemical abstracts, nuclear science abstracts, INIS Atomindex and also some scattered search through journals and reports available in the B.A.R.C. library. However, in spite of sincere attempts for a wide coverage, no claim is being made towards the exhaustiveness of this bibliography. (author)

  18. Long term assurance of supply of heavy water

    International Nuclear Information System (INIS)

    The answer of Switzerland and Great Britain to a number of questions concerning the long-term assurance of the supply of heavy water are presented. The original problems are seen in the wider context of raw materials supply and its assurance in general. Non-proliferation aspects are touched

  19. Valuation of Embalse Nuclear Power Plant and of heavy water

    International Nuclear Information System (INIS)

    The author describes the Nuclear Power Plant characteristics, the building work, the heavy water valuation criteria and the reasons why he considers that any capital good can be valuated by means of cash-flow. The value of replacement of Embalse Nuclear Power Plant is of U$S 1.593.538.000 (authors)

  20. Embalse nuclear power plant and heavy water valuation

    International Nuclear Information System (INIS)

    The author describes the nuclear power plant characteristics, the building work, the heavy water valuation criteria and the reasons why he considers that any capital good can be valued by the cash-flow method. The Embalse nuclear power plant replacement value is of U$S 1.593.538.000. (author)

  1. Possibility of using metal uranium fuel in heavy water reactors

    International Nuclear Information System (INIS)

    The review of metal uranium properties including irradiation in the reactor core lead to the following conclusions. Using metal uranium in the heavy water reactors would be favourable from economic point of view for ita high density, i.e. high conversion factor and low cost of fuel elements fabrication. Most important constraint is swelling during burnup and corrosion

  2. Heavy metal contamination and its indexing approach for river water

    International Nuclear Information System (INIS)

    The objective of the study is to reveal the seasonal variations in the river water quality with respect to heavy metals contamination. To get the extend of trace metals contamination, water samples were collected from twelve different locations along the course of the river and its tributaries on summer and the winter seasons. The concentrations of trace metals such as cadmium, chromium, copper, cobalt, iron, manganese, nickel, lead, mercury and zinc were determined using atomic absorption spectrophotometer. Most of the samples were found within limit of Indian drinking water standard (IS: 10500). The data generated were used to calculate the heavy metal pollution index of river water. The mean values of HPI were 36.19 in summer and 32.37 for winter seasons and these values are well below the critical index limit of 100 because of the sufficient flow in river system. Mercury and chromium could not be traced in any of the samples in the study area.

  3. Nuclear generating station and heavy water plant cost estimates for strategy studies

    International Nuclear Information System (INIS)

    Nuclear generating station capital, operating and maintenance costs are basic input data for strategy analyses of alternate nuclear fuel cycles. This report presents estimates of these costs for natural uranium CANDU stations, CANDU stations operating on advanced fuel cycles, and liquid metal fast breeder reactors. Cost estimates for heavy water plants are also presented. The results show that station capital costs for advanced fuel cycles are not expected to be significantly greater than those for natural uranium stations. LMFBR capital costs are expected to be 25-30 percent greater than for CANDU's. (auth)

  4. Novel biopolymer-coated hydroxyapatite foams for removing heavy-metals from polluted water

    Energy Technology Data Exchange (ETDEWEB)

    Vila, M.; Sanchez-Salcedo, S.; Cicuendez, M.; Izquierdo-Barba, I. [Inorganic and BioInorganic Chemistry Department, Pharmacy Faculty, Universidad Complutense de Madrid, Plaza de Ramon y Cajal s/n, 28040 Madrid (Spain); Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN (Spain); Vallet-Regi, Maria, E-mail: vallet@farm.ucm.es [Inorganic and BioInorganic Chemistry Department, Pharmacy Faculty, Universidad Complutense de Madrid, Plaza de Ramon y Cajal s/n, 28040 Madrid (Spain); Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN (Spain)

    2011-08-15

    Highlights: {yields} 3D-macroporous biopolymer-coated hydroxyapatite (HA) foams as potential devices for the treatment of heavy metal ions. {yields} HA stable foams coated with biopolymers. {yields} Feasible advance in development of new, easy to handle and low cost water purifying methods. - Abstract: 3D-macroporous biopolymer-coated hydroxyapatite (HA) foams have been developed as potential devices for the treatment of lead, cadmium and copper contamination of consumable waters. These foams have exhibited a fast and effective ion metal immobilization into the HA structure after an in vitro treatment mimicking a serious water contamination case. To improve HA foam stability at contaminated aqueous solutions pH, as well as its handling and shape integrity the 3D-macroporous foams have been coated with biopolymers polycaprolactone (PCL) and gelatine cross-linked with glutaraldehyde (G/Glu). Metal ion immobilization tests have shown higher and fast heavy metals captured as function of hydrophilicity rate of biopolymer used. After an in vitro treatment, foam morphology integrity is guaranteed and the uptake of heavy metal ions rises up to 405 {mu}mol/g in the case of Pb{sup 2+}, 378 {mu}mol/g of Cu{sup 2+} and 316 {mu}mol/g of Cd{sup 2+}. These novel materials promise a feasible advance in development of new, easy to handle and low cost water purifying methods.

  5. Novel biopolymer-coated hydroxyapatite foams for removing heavy-metals from polluted water

    International Nuclear Information System (INIS)

    Highlights: → 3D-macroporous biopolymer-coated hydroxyapatite (HA) foams as potential devices for the treatment of heavy metal ions. → HA stable foams coated with biopolymers. → Feasible advance in development of new, easy to handle and low cost water purifying methods. - Abstract: 3D-macroporous biopolymer-coated hydroxyapatite (HA) foams have been developed as potential devices for the treatment of lead, cadmium and copper contamination of consumable waters. These foams have exhibited a fast and effective ion metal immobilization into the HA structure after an in vitro treatment mimicking a serious water contamination case. To improve HA foam stability at contaminated aqueous solutions pH, as well as its handling and shape integrity the 3D-macroporous foams have been coated with biopolymers polycaprolactone (PCL) and gelatine cross-linked with glutaraldehyde (G/Glu). Metal ion immobilization tests have shown higher and fast heavy metals captured as function of hydrophilicity rate of biopolymer used. After an in vitro treatment, foam morphology integrity is guaranteed and the uptake of heavy metal ions rises up to 405 μmol/g in the case of Pb2+, 378 μmol/g of Cu2+ and 316 μmol/g of Cd2+. These novel materials promise a feasible advance in development of new, easy to handle and low cost water purifying methods.

  6. Measuring the pD of heavy water solutions

    International Nuclear Information System (INIS)

    Analogously to the chemistry of aqueous solutions, a chemistry of heavy water solutions can be developed and, correspondingly, by measuring the pD value - the activity of deuterium ions - the behavior of these solutions can be characterized. The cells for measurement of pD can be achieved similarly to the cell for pH, by using Ag/AgCl electrodes and thus a device for measuring the acid-basic balance in a heavy water solution can be made by measuring the electromotive force and establishing a corresponding pD scale. A strict comparison between pD and pH is not possible since both scales are conventional. Values of paD and paH for phosphate solutions of the same molar concentration in heavy and light water, respectively, differs constantly between them by 0.6 units. Such differences in various solutions, using glass electrodes and control calomel electrodes, allowed getting a more exact value (0.41 pH units) for solutions of molar concentration, with a standard deviation of 0.031. Thus, a pD value can be obtained with a pH-meter with glass and control calomel electrodes by applying the correction relation, plus 0,41 units. We have done such determinations by using a domestic made control electrode of the type HC Ag/AgCl pH=7. Determinations with sodium carbonate and iron and sodium chloride solutions in light and heavy water, at the same concentrations, were carried out. The values recorded from the pH-meter for heavy water solutions are lower than the pH values by 0.407 units, so that this value must be added to the pH readings to get the pD values. The standard deviation of these determinations was 0.012 pH units

  7. Materials for advanced water cooled reactors

    International Nuclear Information System (INIS)

    The current IAEA programme in advanced nuclear power technology promotes technical information exchange between Member States with major development programmes. The International Working Group on Advanced Technologies for Water Cooled Reactors recommended to organize a Technical Committee Meeting for the purpose of providing an international forum for technical specialists to review and discuss aspects regarding development trends in material application for advanced water cooled reactors. The experience gained from the operation of current water cooled reactors, and results from related research and development programmes, should be the basis for future improvements of material properties and applications. This meeting enabled specialists to exchange knowledge about structural materials application in the nuclear island for the next generation of nuclear power plants. Refs, figs, tabs

  8. Heavy water technology and its contribution to energy sustainability

    International Nuclear Information System (INIS)

    Full text: As the global nuclear industry expands several markets are exploring avenues and technologies to underpin energy security. Heavy water reactors are the most versatile power reactors in the world. They have the potential to extend resource utilization significantly, to allow countries with developing industrial infrastructures access to clean and abundant energy, and to destroy long-lived nuclear waste. These benefits are available by choosing from an array of possible fuel cycles. Several factors, including Canada's early focus on heavy-water technology, limited heavy-industry infrastructure at the time, and a desire for both technological autonomy and energy self-sufficiency, contributed to the creation of the first commercial heavy water reactor in 1962. With the maturation of the industry, the unique design features of the now-familiar product-on-power refuelling, high neutron economy, and simple fuel design-make possible the realization of its potential fuel-cycle versatility. As resource constrains apply pressure on world markets, the feasibility of these options have become more attractive and closer to entering widespread commercial application

  9. Status of advanced technology and design for water cooled reactors: Light water reactors

    International Nuclear Information System (INIS)

    Water reactors represent a high level of performance and safety. They are mature technology and they will undoubtedly continue to be the main stream of nuclear power. There are substantial technological development programmes in Member States for further improving the technology and for the development of new concepts in water reactors. Therefore the establishment of an international forum for the exchange of information and stimulation of international co-operation in this field has emerged. In 1987 the IAEA established the International Working Group on Advanced Technologies for Water-Cooled Reactors (IWGATWR). Within the framework of IWGATWR the IAEA Technical Report on Status of Advanced Technology and Design for Water Cooled Reactors, Part I: Light Water Reactors and Part II: Heavy Water Reactors has been undertaken to document the major current activities and different trends of technological improvements and developments for future water reactors. Part I of the report dealing with LWRs has now been prepared and is based mainly on submissions from Member States. It is hoped that this part of the report, containing the status of advanced light water reactor design and technology of the year 1987 and early 1988 will be useful for disseminating information to Agency Member States and for stimulating international cooperation in this subject area. 93 refs, figs and tabs

  10. Removal and recovery of tritium from light and heavy water

    International Nuclear Information System (INIS)

    A method and apparatus for removing tritium from light water are described, comprising contacting tritiated feed water in a catalyst column in countercurrent flow with hydrogen gas originating from an electrolysis cell so as to enrich this feed water with tritium from the electrolytic hydrogen gas and passing the tritium enriched water to an electrolysis cell wherein the electrolytic hydrogen gas is generated and then fed upwards through the catalyst column or recovered as product. The tritium content of the hydrogen gas leaving the top of the enricher catalyst column is further reduced in a stripper column containing catalyst which transfers the tritium to a countercurrent flow of liquid water. Anodic oxygen and water vapour from the anode compartment may be fed to a drier and condensed electrolyte recycled with a slip stream or recovered as a further tritium product stream. A similar method involving heavy water is also described. (author)

  11. Conceptual design of a large heavy water reactor for US siting

    International Nuclear Information System (INIS)

    Information is presented concerning fuel management and safety and licensing assessment of the pressurized heavy water reactor; and commercial introduction of the pressurized heavy water reactor in the United States

  12. Conceptual design of a large heavy water reactor for US siting

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, N L; Jesick, J F

    1979-09-01

    Information is presented concerning fuel management and safety and licensing assessment of the pressurized heavy water reactor; and commercial introduction of the pressurized heavy water reactor in the United States.

  13. Thorium utilization in heavy water moderated Accelerator Driven Systems

    International Nuclear Information System (INIS)

    Research on Accelerator Driven Systems (ADSs) is being carried out around the world primarily with the objective of waste transmutation. Presently, the volume of waste in India is small and therefore there is little incentive to develop ADS based waste transmutation technology immediately. With limited indigenous U availability and the presence of large Th deposits in the country, there is a clear incentive to develop Th related technologies. India also has vast experience in design, construction and operation of heavy water moderated reactors. Heavy water moderated reactors employing solid Th fuels can be self sustaining, but the discharge burnups are too low to be economical. A possible way to improve the performance such reactors is to use an external neutron source as is done in ADS. This paper discusses our studies on Th utilization in heavy water moderated ADSs. The study is carried out at the lattice level. The time averaged k-infinity of the Th bundle from zero burnup up to the discharge burnup is taken to be the same as the core (ensemble) averaged k-infinity. For the purpose of the analysis we have chosen standard PHWR and AHWR assemblies. Variation of the pitch and coolant (H2O/D2O) are studied. Both, the once through cycle and the recycling option are studied. In the latter case the study is carried out for various enrichments (% 233U in Th) of the recycled Th fuel bundles. The code DTF as modified for lattice and burnup calculations (BURNTRAN) was used for carrying out the study. The once through cycle represents the most attractive ADS concept (Th burner ADS) possible for Th utilization. It avoids reprocessing of Th spent fuel and in the ideal situation the use of any fissile material either initially or for sustaining itself. The gain in this system is however rather low requiring a high power accelerator and a substantial fraction of the power generated to be fed back to the accelerator. The self sustaining Th-U cycle in a heavy moderated ADS is a

  14. Three-component U-Pu-Th fuel for plutonium irradiation in heavy water reactors

    OpenAIRE

    Peel Ross; Van Den Durpel Luc; Ogden Mark Daniel; Whittle Karl Rhys

    2016-01-01

    This paper discusses concepts for three-component fuel bundles containing plutonium, uranium and thorium for use in pressurised heavy water reactors, and cases for and against implementation of such a nuclear energy system in the United Kingdom. Heavy water reactors are used extensively in Canada, and are deploying within India and China, whilst the UK is considering the use of heavy water reactors to manage its plutonium inventory of 140 tonnes. The UK heavy water reactor proposal uses a mix...

  15. Three-component U-Pu-Th fuel for plutonium irradiation in heavy water reactors

    OpenAIRE

    Peel, R.; Van Den Derpel, L.; Whittle, K.; Ogden, M.

    2016-01-01

    This paper discusses concepts for three-component fuel bundles containing plutonium, uranium and thorium for use in pressurised heavy water reactors, and cases for and against implementation of such a nuclear energy system in the United Kingdom. Heavy water reactors are used extensively in Canada, and are deploying within India and China, whilst the UK is considering the use of heavy water reactors to manage its plutonium inventory of 140 tonnes. The UK heavy water reactor proposal uses a mix...

  16. Use of CECE process for heavy water detritiation

    International Nuclear Information System (INIS)

    Full text: The experimental industrial plant has been built in PNPI for the development of the combined electrolysis catalytic exchange (CECE) technology for hydrogen isotope separation. The process uses a liquid phase catalytic exchange (LPCE) column and electrolysis cells to convert water to hydrogen. The plant has been in operation since 1995. In parallel with a development of CECE process for hydrogen isotope separation the plant is used for reprocessing tritium heavy water waste. Processing waste with the content of ∼47 % of heavy hydrogen and 108 Bq/kg of tritium, the plant produces 99.85-99.995% heavy water and deuterium gas for science and industry. Owing to industrial demands for heavy water with reduced tritium content, the plant was modified and additional equipment and procedures were put in place to operate in the detritiation mode. High detritiation factors have already been achieved during the initial heavy water detritiation test. In this test hydrogen catalytic burner is used as an upper reflux device. After prolonged operation campaigns it was decided to update the plant with an additional separation column connected with existing equipment. The main parameters of the new exchange column are the same as the old one: overall height of 7.5 m, inner diameter of 100 mm. The column is filled with alternating layers of hydrophobic catalyst developed by Mendeleev University and stainless steel spiral-prismatic packing. It consists of five separation sections connected through a distributor of liquid. The separation height of the column is 5.4 m. The new column and some additional equipment have been set in the plant so that tritiated deuterium enters the bottom of the column from electrolysis cells. Tritiated deuterium flowing up the column is purified from tritium and then enters the bottom of the second (old) column. The natural water flowing down in the second column is enriched in deuterium and is fed to the top of the first column. Deuterium

  17. Advancement of light water reactor technology

    International Nuclear Information System (INIS)

    The Japanese technology of light water reactors is based on the technology imported from abroad around 1970, and the experience has been accumulated by the construction, operation and repair of light water reactors as well as the countermeasures to various troubles, moreover, the improvement and standardization of light water reactors have been promoted. As the result, recently the high capacity ratio has been attained, and the LWR technology has firmly taken root in Japan. The Subcommittee for the Advancement of Light Water Reactor Technology of the Advisory Committee for Energy has examined the subjects of technical development and the way the development should be in order to decide the strategy to advance LWR technology, and drawn up the interim report. The change of situation around the LWRs in Japan and the necessity to advance the technology, the target of advancing LWR technology and the subjects of the technical development, the system for the technical development and the securement of fund, and international cooperation are reported. The subjects of development are the pursuit of higher reliability and economic efficiency, the extension of plant life, the improvement of repairability and the reduction of radiation exposure, the improvement of operational capability, the reduction of wastes, the techniques for reactor decommissioning and the diversified location. (Kako, I.)

  18. Thermohydraulic relationships for advanced water cooled reactors

    International Nuclear Information System (INIS)

    This report was prepared in the context of the IAEA's Co-ordinated Research Project (CRP) on Thermohydraulic Relationships for Advanced Water Cooled Reactors, which was started in 1995 with the overall goal of promoting information exchange and co-operation in establishing a consistent set of thermohydraulic relationships which are appropriate for use in analyzing the performance and safety of advanced water cooled reactors. For advanced water cooled reactors, some key thermohydraulic phenomena are critical heat flux (CHF) and post CHF heat transfer, pressure drop under low flow and low pressure conditions, flow and heat transport by natural circulation, condensation of steam in the presence of non-condensables, thermal stratification and mixing in large pools, gravity driven reflooding, and potential flow instabilities. The objectives of the CRP are (1) to systematically list the requirements for thermohydraulic relationships in support of advanced water cooled reactors during normal and accident conditions, and provide details of their database where possible and (2) to recommend and document a consistent set of thermohydraulic relationships for selected thermohydraulic phenomena such as CHF and post-CHF heat transfer, pressure drop, and passive cooling for advanced water cooled reactors. Chapter 1 provides a brief discussion of the background for this CRP, the CRP objectives and lists the participating institutes. Chapter 2 provides a summary of important and relevant thermohydraulic phenomena for advanced water cooled reactors on the basis of previous work by the international community. Chapter 3 provides details of the database for critical heat flux, and recommends a prediction method which has been established through international co-operation and assessed within this CRP. Chapter 4 provides details of the database for film boiling heat transfer, and presents three methods for predicting film boiling heat transfer coefficients developed by institutes

  19. Influence of Agriculture on Water Quality: Significance of Heavy Metals Monitoring

    OpenAIRE

    Nusreta Đonlagić; Amra Odobašić; Amra Bratovčić

    2007-01-01

    Agricultural activities directly influence the quality of water systems. Investigations showed that application of various agro-technical measures results with the pollution of water streams with heavy metals and other polluters. Increased concentrations of heavy metals result with intake of heavy metals and their transfer to food chains, and for that reason it is necessary to monitor the content of heavy metals regularly. Broad investigations of bio-geochemical cycling of heavy metals in the...

  20. [Effect of heavy water on the viability of bacteria].

    Science.gov (United States)

    Dronova, N V; Parkhomenko, T V; Popov, V G; Sventitskiĭ, E N; Iakovleva, L Iu

    1988-01-01

    Influence of heavy water (D2O) on the membrane energization, the efflux of hydrogen ions and the respiration of bacteria E. coli M-17 was studied. As has been shown, heavy water of a low concentration (0.05-0.20% v/v) activates and of a high concentration (above 10%) inhibits the absorption of lipophilic cation tetraphenylphosphonium (TPP+) and of oxygen by cells. The return of these characteristics to the initial levels after the removal of D2O points to a reversible action of D2O. A protective effect of D2O towards membrane energization and rate of respiration on dried cells was observed. This fact is in agreement with the data on viability of bacteria. The indicated protective action increases at the stage of rehydration in the presence of D2O. PMID:3390482

  1. Technological improvements in the equipment for manufacturing of heavy water

    International Nuclear Information System (INIS)

    The most important improvements in this direction are: isotope separation technology of heavy water on a hot-cold stage with column of equilibration; anticorrosion protection technology against the action of hydrogen sulfide through sulphide coating of the internal surfaces of installations; chemical cleaning technology of the H2 O-H2 S isotope exchange equipment; maintenance technology with gaseous medium of nitrogen and hydrogen sulfide of the corrosion-sensitive equipment; monitoring and leak testing system of the H2 O-H2 S isotope exchange equipment. These developments were applied in the operation of GS Rm. Valcea pilot plant and transferred to ROMAG Drobeta, the Romanian heavy water production plant

  2. Energy conservation measures adopted at Heavy Water Plant, Manuguru

    International Nuclear Information System (INIS)

    The importance of conservation of energy is well recognised all over the world as the world reserves of fossil fuels will eventually run out depending on the rate of their use. This paper deals with various energy conservation schemes adopted at Heavy Water Plant, Manuguru (HWPM). Most energy conservation measures offer large financial saving with very short pay back periods. This fact has been well recognised by the management of HWPM as well as Heavy Water Board and their wholehearted and enthusiastic approach to energy conservation and energy management yielded very good results in reducing the operating cost. The process of energy conservation is not a one time exercise. Persistent efforts are on to identify the areas like condition of heat exchangers, margins in control valves, steam and condensate leakages etc. for further reduction in energy consumption

  3. Environmental health scoping study at Bruce Heavy Water Plant

    International Nuclear Information System (INIS)

    There are concerns that hydrogen sulfide released from the Heavy Water Plant near Kincardine, Ontario may be the cause of the mortalities and morbidities observed in a nearby flock of sheep. The Philosopher's Wool sheep farm is about four kilometres south-southeast of the Bruce Heavy Water Plant. Ontario Hydro, the owner and operator of the Bruce Heavy Water Plant, claims that hydrogen sulphide emissions from the Bruce Heavy Water Plant are within regulatory limits and well below levels that cause harm. Accordingly, the Atomic Energy Control Board commissioned the Alberta Environmental Centre, Alberta Department of Environmental Protection, to develop a scoping study for this environmental health issue. The first objective was to describe a field investigation model to define clearly the environmental health and operation of the sheep farm. The second objective was to describe possible exposure patterns and develop a holistic environmental pathway model. If appropriate, the third study objective was to describe animal models of the actual situation to elucidate specific aspects of the environmental health concerns. It was not the objective of this report to provide a definitive answer to the present environmental health issue. Ontario Hydro provided data to the Alberta Environmental Centre, as di the sheep farmer, the attending veterinarian, the University of Guelph study team, and the Atomic Energy Control Board. A six-tiered strategy of sequential evaluations of the ovine health problem is based on the multiple-response paradigm. It assumes the observed ovine health results are the result of multiple effector events. Each tier constitutes a separate, but inter-related, study. Sequential evaluation and feedback of each tier allow sound scientific judgements and efficient use of resources. (author). 59 refs., 11 tabs., 22 figs

  4. Possibilities of using metal uranium fuel in heavy water reactors

    International Nuclear Information System (INIS)

    There are serious economic reasons for using metal uranium in heavy water reactors, because of its high density, i.e. high conversion factor, and low cost of fuel elements production. Most important disadvantages are swelling at high burnup and corrosion risk. Some design concepts and application of improved uranium obtained by alloying are promising for achievement of satisfactory stability of metal uranium under reactor operation conditions

  5. Integrated inspection programs at Bruce Heavy Water Plant

    International Nuclear Information System (INIS)

    Quality pressure boundary maintenance and an excellent loss prevention record at Bruce Heavy Water Plant are the results of the Material and Inspection Unit's five inspection programs. Experienced inspectors are responsible for the integrity of the pressure boundary in their own operating area. Inspectors are part of the Technical Section, and along with unit engineering staff, they provide technical input before, during, and after the job. How these programs are completed, and the results achieved, are discussed. 5 figs., 1 appendix

  6. The chemistry of the PSGHWR heavy water moderator system

    International Nuclear Information System (INIS)

    The PSGHWR heavy water moderator and helium overblanket circuits, and the heavy water purification plant are described. Details of the deuterisation and dedeuterisation of ion exchange resin charges for the purification plant are given, and a pattern of consistency over seventeen deuterisations of anion and cation beds is shown. The chemistry specification for the moderator system is given, and the changing philosophy of ion exchange plant operation to maintain this specification, from early operation with continuous flow through cation and anion clean up columns, to the current mode of minimum intermittent flow, is explained. Anionic and cationic impurities and radio nuclides found in the moderator are listed, and their sources examined. The inter-relation between the ion exchange plant as a source as well as a remover of impurities and the part played by peroxide is examined. Radiolysis data is presented and an attempt is made to explain the correlation between radiolysis rate and impurity concentrations, ion exchange column operation and other plant parameters. A soluble poison, enriched 10boron, is used for balancing excess fuel reactivity. The boron cycle and method of control of boron concentration are explained, and experience of anion exchange resin capacity for boron at different input concentrations is given. Experience covering 26 regenerations of the anion beds, mostly using deutero chemicals, and details of the method of recovery of deuteroboric acid and potassium deuteroxide by electrodialysis are given. Finally, heavy water losses and isotopic degradation of D2O during 8 years of operation are examined. (author)

  7. The Battle for Heavy Water Three physicists' heroic exploits

    CERN Multimedia

    2002-01-01

    Up until the end of the 1970s you could still catch a glimpse of his massive silhouette in the corridors of CERN. Lew Kowarksi, one of the pioneers of the Laboratory, was not only a great physicist; he was also a genuine hero of World War II. In 1940, along with Frédéric Joliot and Hans von Halban, Lew Kowarski managed to get the entire world supply of heavy water away to safety from the Nazis after a fantastic escape from occupied France. At the end of the war, the three physicists played themselves in a film about their adventures entitled 'la Bataille de l'eau lourde'. This film, which has been loaned to us by the French National Film Library, will be shown at CERN for the first time next Thursday. At the beginning of the war, heavy water (D20, two atoms of deuterium and one oxygen atom) was of strategic importance. In 1939 Frédéric Joliot, aided by Hans von Halban and Lew Kowarski, demonstrated the nuclear chain reaction and the moderator role that heavy water plays in it. A few weeks before the inv...

  8. DEGRADATION EVALUATION OF HEAVY WATER DRUMS AND TANKS

    Energy Technology Data Exchange (ETDEWEB)

    Mickalonis, J.; Vormelker, P.

    2009-07-31

    Heavy water with varying chemistries is currently being stored in over 6700 drums in L- and K-areas and in seven tanks in L-, K-, and C-areas. A detailed evaluation of the potential degradation of the drums and tanks, specific to their design and service conditions, has been performed to support the demonstration of their integrity throughout the desired storage period. The 55-gallon drums are of several designs with Type 304 stainless steel as the material of construction. The tanks have capacities ranging from 8000 to 45600 gallons and are made of Type 304 stainless steel. The drums and tanks were designed and fabricated to national regulations, codes and standards per procurement specifications for the Savannah River Site. The drums have had approximately 25 leakage failures over their 50+ years of use with the last drum failure occurring in 2003. The tanks have experienced no leaks to date. The failures in the drums have occurred principally near the bottom weld, which attaches the bottom to the drum sidewall. Failures have occurred by pitting, crevice and stress corrosion cracking and are attributable, in part, to the presence of chloride ions in the heavy water. Probable degradation mechanisms for the continued storage of heavy water were evaluated that could lead to future failures in the drum or tanks. This evaluation will be used to support establishment of an inspection plan which will include susceptible locations, methods, and frequencies for the drums and tanks to avoid future leakage failures.

  9. Using MAGNA-IR 750 spectrometer in heavy water measurements

    International Nuclear Information System (INIS)

    Since ten years the Laboratory of Deuterium Metrology is operational and provides the calibration standard to the units throughout the country which produce and use heavy water. During this period interlaboratory comparisons were conducted with laboratories of similar character of Argentina, Canada, India and USA. In 1994 an indirect intercalibration with Canada to determine the concentration of heavy water introduced for the first loading of the Cernavoda Unit 1 reactor has been performed. In 1996 a new intercalibration has been made with the occasion of handing back the heavy water lent by the Canadian party. This work presents the measurement techniques and the practical results obtained in the Laboratory of Deuterium Metrology of INC-DTCI-ICIS Rm.Valcea. The analyses were carried out with the MAGNA-IR 750 spectrophotometer produced by NICOLET. This type of instruments is based on a interferometer and makes use of Fourier transform, what leads to improving the infrared spectrum quality and 'implicitly' to increase the accuracy of the results obtained up to value of 0.005% of the D2O mass. Also, a significant reduction of the time needed for making an analysis has been achieved

  10. Freeze-out dynamics in heavy-ion collisions: Recent advances

    Indian Academy of Sciences (India)

    Francesco Becattini

    2015-05-01

    We briefly review recent advances in the subject of hadron production in relativistic heavy-ion collisions. We focus on the issues of chemical freeze-out, chemical equilibration and the role of post-hadronization inelastic collisions. From the observations collected in elementary and heavy-ion collisions, a picture emerges in which hadrons are born in chemical equilibrium at hadronization, thereafter undergoing inelastic and elastic collisions whose impact on the primordial distribution depends on the system size.

  11. Graphene-based sensors for detection of heavy metals in water: a review.

    Science.gov (United States)

    Chang, Jingbo; Zhou, Guihua; Christensen, Erik R; Heideman, Robert; Chen, Junhong

    2014-06-01

    Graphene (G) is attracting significant attention because of its unique physical and electronic properties. The production of graphene through the reduction of graphene oxide (GO) is a low-cost method. The reduction of GO can further lead to electrically conductive reduced GO. These graphene-based nanomaterials are attractive for high-performance water sensors due to their unique properties, such as high specific surface areas, high electron mobilities, and exceptionally low electronic noise. Because of potential risks to the environment and human health arising from heavy-metal pollution in water, G-/GO-based water sensors are being developed for rapid and sensitive detection of heavy-metal ions. In this review, a general introduction to graphene and GO properties, as well as their syntheses, is provided. Recent advances in optical, electrochemical, and electrical detection of heavy-metal ions using graphene or GO are then highlighted. Finally, challenges facing G/GO-based water sensor development and outlook for future research are discussed. PMID:24740529

  12. On the Effect of Lengthening Circadian Rhythm by Heavy Water

    Directory of Open Access Journals (Sweden)

    Akhmedov T. R.

    2014-01-01

    Full Text Available The problem of time sensor of biological clock (BC attracts interest of many scientists, and a great number of experiments are being conducted to stud y the influence of vari- ous physical and chemical factors on functioning of BC. Special attention is drawn to studying the influence of heavy water (D 2 O on functioning of BC that always leads to lengthening of circadian rhythms (CR. This work presents theoretical consideration of lengthening of CR, when hydrogen (H 2 in water is replaced by deuterium (D 2 , that is based on spacial difference of energy levels with similar principle quantum numbers.

  13. Heavy metal ions adsorption from mine waters by sawdust

    OpenAIRE

    G. Bogdanović; Milan Gorgievski; Dragana Božić; Velizar Stanković

    2009-01-01

    In this work the results on the batch and column adsorption of copper and some associated ions by employing linden and poplar sawdust as a low-cost adsorbent are presented. The mine water from a local abandoned copper mine, as well as synthetic solutions of those ions which are the main constituents of the mine water were both used as a model-system in this study. The adsorption ability of the chosen sawdust to adsorb heavy metal ions is considered as a function of the initial pH of the solut...

  14. Advancing Water Science through Improved Cyberinfrastructure

    Science.gov (United States)

    Koch, B. J.; Miles, B.; Rai, A.; Ahalt, S.; Band, L. E.; Minsker, B.; Palmer, M.; Williams, M. R.; Idaszak, R.; Whitton, M. C.

    2012-12-01

    Major scientific advances are needed to help address impacts of climate change and increasing human-mediated environmental modification on the water cycle at global and local scales. However, such advances within the water sciences are limited in part by inadequate information infrastructures. For example, cyberinfrastructure (CI) includes the integrated computer hardware, software, networks, sensors, data, and human capital that enable scientific workflows to be carried out within and among individual research efforts and across varied disciplines. A coordinated transformation of existing CI and development of new CI could accelerate the productivity of water science by enabling greater discovery, access, and interoperability of data and models, and by freeing scientists to do science rather than create and manage technological tools. To elucidate specific ways in which improved CI could advance water science, three challenges confronting the water science community were evaluated: 1) How does ecohydrologic patch structure affect nitrogen transport and fate in watersheds?, 2) How can human-modified environments emulate natural water and nutrient cycling to enhance both human and ecosystem well-being?, 3) How do changes in climate affect water availability to support biodiversity and human needs? We assessed the approaches used by researchers to address components of these challenges, identified barriers imposed by limitations of current CI, and interviewed leaders in various water science subdisciplines to determine the most recent CI tools employed. Our preliminary findings revealed four areas where CI improvements are likely to stimulate scientific advances: 1) sensor networks, 2) data quality assurance/quality control, 3) data and modeling standards, 4) high performance computing. In addition, the full potential of a re-envisioned water science CI cannot be realized without a substantial training component. In light of these findings, we suggest that CI

  15. Sonication for advanced drinking water treatment

    Institute of Scientific and Technical Information of China (English)

    ZHANG Guang-ming; WEI Xi-zhu; LI Xiang-kun; ZHANG Jie; DOU Zi-bo

    2009-01-01

    This paper investigated the feasibility of sonication as an advanced treatment method for drinking water production and used comprehensive indexes of water quality to examine its efficiency. Results show that sonication significantly reduces the toxicity of water. Sonication with 5 W/L at 90 kHz lasting for 30 min decreases he water SUVA and the disinfection byproduct formation potential (DBPFP) by 38.7% and 27.2% respective ly. Sonieation also decreases the UV254 by more than 50% through destroying unsaturated chemical bonds.Higher sound intensity and higher frequency benefit the reduction of TOC and UV254, Besides, sonication significantly increases the affinity of organics with granular activated carbon (GAC), and thus the hybrid sonication-GAC method reduces the water TOC, COD, UV254, and DBPFP by 78. 3%, 69.4%, 75.7%, and 70. 0% respectively. Therefore, sonieation and the hybrid sonieation-GAC method are proposed as advanced treatment methods for drinking water.

  16. Critical heat flux measurements in rod bundles using light water and heavy water as coolant

    International Nuclear Information System (INIS)

    A series of Critical Heat Flux (CHF), subchannel mixing and pressure drop tests were performed on a full scale simulated 37 element fuel bundle at the Heat Transfer Research Facility of Columbia University for Siemens/Kraftwerk Union Ag. of Germany. The experimental program consisted of thermal hydraulic testing of a full scale 37 element fuel bundle 3000 mm long to determine two phase pressure drop and CHF characteristics. The test were performed on the simulated fuel bundle in a vertical circular test housing with an outer diameter of 108.25 mm. The axial power distribution was uniform, while the radial power distribution was non-uniform with a heat flux depression of about 35%. The bundle geometry was maintained by spacer grids. In this experimental program, 92 CHF runs were performed using light water (H2O) as the coolant, and 22 CHF runs were performed using heavy water (D2O) as the coolant to reduce the risk of heavy water loss. The CHF tests covered the following parameter ranges: pressure from 70 to 150 bars in light water and at 100 and 115 bars in heavy water; mass velocities from 1000 to 5600 kg/m2s, and inlet temperatures from 200 to 320 degree C. The experiments carried out in heavy water were in essence a duplication of the test conditions of the ones obtained in light water, facilitating a direct comparison of the results using both fluids. Furthermore, an evaluation of the experiments using the subchannel analysis method was made with the results being presented. Analysis shows that CHF with heavy water as a coolant can be predicted with sufficient accuracy by applying Ahmad's scaling laws for fluid -to fluid modeling. Therefore, CHF correlations developed and verified for light water reactors can be applied to design heavy water cooled reactor cores

  17. Elementary Analyses and Heavy Metal Contents of Tap Waters in Konuralp District: Comparison of Mains Water, Spring Water and Zamzam

    Directory of Open Access Journals (Sweden)

    Muammer Yılmaz 1

    2014-09-01

    Full Text Available Objective: We meet our water needs such as city water supply, natural spring water, Zamzam water was aimed to compare in terms of chemical ion concentration and heavy metal content. Methods: City water from the four regions with different source, Zamzam water and bottled natural spring water in samples, ions and heavy metal values measured. Results have been assessed according to the criteria specified in the United States environmental protection agency (EPA and the World Health Organization (WHO. Results: In the sample of tap water taken from Konuralp, Al and Fe values were found over the EPA-WHO limit value. In the sample of bottled natural spring water, heavy metals are within the limits established. In the sample of Zamzam water Ca+2, Mg+2 values were higher than other samples but not exceeding the limits. In the sample of Zamzam water nitrate (NO3-, and vanadium (V values is very high from samples taken of the city water. Conclusion: Water content may be different with the water supply and environmental effects. More extensive analysis should be done by municipalities to drinking water that contains ions and heavy metal and citizens to know the measurements of the water they drink should be informed periodically of local authority’s websites.

  18. Advances in Target Design for Heavy-Ion Fusion

    International Nuclear Information System (INIS)

    Over the past few years, the emphasis in heavy ion target design has moved from the distributed radiator target to the 'hybrid' target because the hybrid target allows a larger beam focal spot than the distributed radiator (∼ 5 mm radius rather than ∼ 2 mm radius). The larger spot relaxes some of the requirements on the driver, but introduces some new target physics issues. Most notable is the use of shine shields and shims in the hohlraum to achieve symmetry rather than achieving symmetry by beam placement. The shim is a thin layer of material placed on or near the capsule surface to block a small amount of excess radiation. While we have been developing this technique for the heavy ion hybrid target, the technique can be used in any indirect drive target. We have begun testing the concept of a shim to improve symmetry using a double-ended z-pinch hohlraum on the Sandia Z-machine. Experiments using shimmed thin wall capsules have shown that we can reverse the sign of a P2 asymmetry and significantly reduce the size of a P4 asymmetry. These initial experiments demonstrate the concept of a shim as another method for controlling early time asymmetries in ICF capsules

  19. Advances in target design for heavy ion fusion

    International Nuclear Information System (INIS)

    Over the past few years, the emphasis in heavy ion target design has moved from the distributed radiator target to the 'hybrid' target because the hybrid target allows a larger beam focal spot than the distributed radiator (∼5 mm radius rather than ∼2 mm radius). The larger spot relaxes some of the requirements on the driver, but introduces some new target physics issues. Most notable is the use of shine shields and shims in the hohlraum to achieve symmetry rather than achieving symmetry by beam placement. The shim is a thin layer of material placed on or near the capsule surface to block a small amount of excess radiation. While we have been developing this technique for the heavy ion hybrid target, the technique can also be used in any indirect drive target. We have begun testing the concept of a shim to improve symmetry using a double-ended z-pinch hohlraum on the Sandia Z-machine. Experiments using shimmed thin wall capsules have shown that we can reverse the sign of a P2 asymmetry and significantly reduce the size of a P4 asymmetry. These initial experiments demonstrate the concept of a shim as another method for controlling early time asymmetries in ICF capsules

  20. Cooling water treatment for heavy water project (Paper No. 6.9)

    International Nuclear Information System (INIS)

    With minor exceptions, water is the preferred industrial medium for the removal of unwanted heat from process systems. The application of various chemical treatments is required to protect the system from water related and process related problems of corrosion, scale and deposition and biofouling. The paper discusses the cooling water problems for heavy water industries along with the impact caused by associated fertilizer units. (author). 6 figs

  1. Uncertainties in gas dispersion at the Bruce heavy water plant

    International Nuclear Information System (INIS)

    There have been concerns regarding the uncertainties in atmospheric dispersion of gases released from the Bruce Heavy Water Plant (BHWP). The concern arises due to the toxic nature of H2S, and its combustion product SO2. In this study, factors that contribute to the uncertainties, such as the effect of the shoreline setting, the potentially heavy gas nature of H2S releases, and concentration fluctuations, have been investigated. The basic physics of each of these issues has been described along with fundamental modelling principles. Recommendations have been provided on available computer models that would be suitable for modelling gas dispersion in the vicinity of the BHWP. (author). 96 refs., 4 tabs., 25 figs

  2. Measurement of the purity of graphite and heavy water

    International Nuclear Information System (INIS)

    The analytical methods used by the C.E.A. are described, I -- Graphite. The determination of the change in the neutron capture cross section from sample to sample is determined by, an oscillation method in the Zoe reactor, or by measuring the attenuation of a neutron flux in the subcritical system Mireille. Methods of analysing total ash, B, H, Cl, Na, Ca. Fe, Mo, Ti, V, Sm, Eu, Dy, S, Co and Cd are described and mean results are given. The methods for sampling are indicated. II -- Heavy crater. The isotopic analysis of heavy water is carried out by infra-red absorption measurements. Chemical purity is evaluated by electrical conductivity measurements, B, Na, Mg, K, Cr, Mn, Ni, Cu, Cd, are determined by spectrographic methods, and Cl-, NO3-, SO4--, NH4+ by chemical methods; finally, sensitive pH measurements are described

  3. Dissociative electron attachment to water and heavy water

    International Nuclear Information System (INIS)

    We will present new results on the dissociative electron attachment cross sections of the production of OH-, O- and H- formed from water vapor and the corresponding deuterated species. A crossed beams experiment already described in the literature was used. Furthermore, the effect of temperature on the formation of the mentioned negative fragment ions was investigated. An upcoming review article about inelastic collisions of electrons with water has shown discrepancies in previous studies. Our results are compared to the available previous data and show good agreement concerning the relative cross sections ratios of the ions, however, differences are observed in the energy positions of the resonances. (author)

  4. BUCKLING ANALYSES OF A HEAVY COLUMN CONSIDERATED IN WATER

    Directory of Open Access Journals (Sweden)

    Yeliz PEKBEY

    2008-02-01

    Full Text Available In 1744, the critical buckling load with the assumption of uniform cross-section without weight of column were computed by Euler. Whenever an economical solution is required, the weight of column must be considered for solution of buckling analyses. In literature, the critical buckling load and asymptotic behaviour of heavy column in condition of atmosphere have inverstigated for ten different support types. When this literature is examined, it is stated that the differential equations of for four different suppport types in condition of water is similar to condition of atmosphere. However, the differential equations of other four different suppport types in condition of water is different from to condition of atmosphere. And it is stated that the critical buckling load these different suppport types in condition of water is not calculated from condition of atmosphere. The goals of this paper are to develop self weight buckling of column at its top fixed and lower end fixed-roller supported in condition of water. This paper, presents a analytical method for calculating the critical buckling load of the heavy column.

  5. How Water Advances on Superhydrophobic Surfaces

    Science.gov (United States)

    Schellenberger, Frank; Encinas, Noemí; Vollmer, Doris; Butt, Hans-Jürgen

    2016-03-01

    Superliquid repellency can be achieved by nano- and microstructuring surfaces in such a way that protrusions entrap air underneath the liquid. It is still not known how the three-phase contact line advances on such structured surfaces. In contrast to a smooth surface, where the contact line can advance continuously, on a superliquid-repellent surface, the contact line has to overcome an air gap between protrusions. Here, we apply laser scanning confocal microscopy to get the first microscopic videos of water drops advancing on a superhydrophobic array of micropillars. In contrast to common belief, the liquid surface gradually bends down until it touches the top face of the next micropillars. The apparent advancing contact angle is 180°. On the receding side, pinning to the top faces of the micropillars determines the apparent receding contact angle. Based on these observations, we propose that the apparent receding contact angle should be used for characterizing superliquid-repellent surfaces rather than the apparent advancing contact angle and hysteresis.

  6. How Water Advances on Superhydrophobic Surfaces.

    Science.gov (United States)

    Schellenberger, Frank; Encinas, Noemí; Vollmer, Doris; Butt, Hans-Jürgen

    2016-03-01

    Superliquid repellency can be achieved by nano- and microstructuring surfaces in such a way that protrusions entrap air underneath the liquid. It is still not known how the three-phase contact line advances on such structured surfaces. In contrast to a smooth surface, where the contact line can advance continuously, on a superliquid-repellent surface, the contact line has to overcome an air gap between protrusions. Here, we apply laser scanning confocal microscopy to get the first microscopic videos of water drops advancing on a superhydrophobic array of micropillars. In contrast to common belief, the liquid surface gradually bends down until it touches the top face of the next micropillars. The apparent advancing contact angle is 180°. On the receding side, pinning to the top faces of the micropillars determines the apparent receding contact angle. Based on these observations, we propose that the apparent receding contact angle should be used for characterizing superliquid-repellent surfaces rather than the apparent advancing contact angle and hysteresis. PMID:26991185

  7. Advances in Chevron RDS technology for heavy oil upgrading flexibility

    Energy Technology Data Exchange (ETDEWEB)

    Scheuerman, G.L.; Johnson, D.R.; Reynolds, B.E.; Bachtel, R.W.; Threlkel, R.S. (Chevron Research and Technology Company, Richmond, CA (United States))

    1993-09-01

    Over the last 20 years, environmental and market forces have not only increased the demand for residuum hydrotreating technology but have also changed it from a technology which simply desulfurizes to one which provides maximum conversion. Simultaneously greater feed flexibility was also being demanded. Chevron has been active throughout this period developing RDS/VRDS technology and the catalysts that go with that technology. Currently, Chevron provides a whole range of RDS catalysts from HDM catalysts which can handle heavy, high metals feeds to active residuum HDN catalysts which can produce RFCC feed. In addition, Chevron has developed a new technology called Onstream Catalyst Replacement (OCR) which allows refiners to handle very high metals feeds without shutting down their residuum hydrotreater for catalyst changeouts. 14 figs., 11 tabs.

  8. Recent Advances in GEO Water Cycle Activities

    Science.gov (United States)

    Lawford, R. G.

    2009-12-01

    Over the past few years GEO (Group on Earth Observations) efforts within the Water Societal Benefit Area (SBA) have been coordinated by the Science Committee of the former Integrated Global Observing Strategy Partnership (IGOS-P) IGWCO (Integrated Global Water Cycle Observations) theme. Within this framework a number of projects related to data system design, product development, and capacity building are being carried out. GEO has recently consolidated the Water SBA activities into three tasks, namely Droughts, Floods and Water Resource Management; Capacity Building for Water Resource Management (in Asia, Africa and the Americas); and Integrated Products for Water Resource Management and Research. In order to strengthen interactions with the GEO and its User Interface Committee, a Water Cycle Community of Practice (COP) was initiated. In addition, within the past year, the IGWCO Science Committee has decided to also function as a Community of Practice in collaboration with the existing Water Cycle COP. This overview will provide background and an update on the GEO Water SBA activities with an emphasis of the way in which these activities are being integrated within the three tasks. It will also describe activities that are planned for 2010 to facilitate this integration. Recent advances related to drought monitoring, capacity and network building, and observational and data systems will be highlighted. New water-related activities arising from collaborations between US GEO and Canada GEO, and through activities within the GEO Architecture and Data Committee, will also be described. This presentation will conclude with a longer-term outlook for water within the GEO framework and provide some guidance for interested experts on how they can become involved in helping to implement these plans.

  9. Stage 1 decommissioning of the steam generating heavy water reactor - current achievements (Winfrith)

    International Nuclear Information System (INIS)

    The Steam Generating Heavy Water Reactor (SGHWR) is located at Winfrith, Dorset, UK. It was a Nuclear Power Plant rated at 100MW(e) and operated successfully from 1968 to 1990. Decommissioning is funded by the Department of Trade and Industry and is the responsibility of the United Kingdom Atomic Energy Authority, which has contracted AEA Technology to manage the project. Decommissioning is now well advanced in accordance with a cost-effective three stage strategy. This paper introduces SGHWR, outlines the economic basis of the decommissioning strategy, summarises the practical achievements and uses the containment strategy to provide an example of environmental considerations. (Author)

  10. Deposition of heavy water on soil and reemission to the atmosphere

    International Nuclear Information System (INIS)

    Field experiments using heavy water as a tracer instead of tritiated water (HTO) were carried out in November 1995 and August 1996 in Japan. The objective of these experiments was to estimate the behavior of HTO in the environment when HTO was released to the atmosphere. We measured the evolution of depth profiles of heavy water concentrations in soil water and compared the reemission rates with the evaporation velocities to study the deposition and reemission of heavy water to/from soil. The depth profiles of heavy water concentrations in soil were expressed by exponential functions of which the gradient depended on the deposition period. The initial reemission rates of heavy water from the soil were the highest, regardless of the meteorological conditions. The reemission occurred not only during the day but also at night, suggesting that the exchange of heavy water in the soil surface layer with H2O in air played a dominant role during nighttime. (orig.)

  11. Consequence of potential accidents in heavy water plants

    International Nuclear Information System (INIS)

    Heavy water plants realize the primary isotopic concentrations of water using H2O-H2S chemical exchange and they are chemical plants. As these plants are handling and spreading large quantities of hydrogen sulphide (high toxic, corrosive, flammable and explosive as) maintained in the process at relative high temperatures and pressures, it is required an assessing of risks associated with the potential accidents. The H2S released in atmosphere as a result of an accident will have negative consequences to property, population and environment. This paper presents a model of consequences quantitative assessment and its outcome for the most dangerous accident in heavy water plants. Several states of the art risk based methods were modified and linked together to form a proper model for this analyse. Five basic steps to identify the risks involved in operating the plants are followed: hazard identification, accident sequence development, H2S emissions calculus, dispersion analyses and consequences determination. A brief description of each step and some information of analysis results are provided. The accident proportions, the atmospheric conditions and the population density in the respective area were accounted for consequences calculus. The specific results of the consequences analysis allow to develop the plant's operating safety requirements so that the risk remain at an acceptable level. (authors)

  12. Emergency electric power supply systems for Pressurised Heavy Water Reactor

    International Nuclear Information System (INIS)

    This safety guide is one of a series of guides, already prepared or are under preparation as a follow-up of the Code of Practice on Design for Safety in Pressurised Heavy Water Based Nuclear Power Plants. The guide is based on the current design of 220 MWe and 500 MWe PHWRs. This safety guide specifically provides guidance on all aspects of safety in designing an emergency electric power supply system and about the basic requirements of other types of power supply systems in NPPs

  13. Topical papers on heavy water, fuel fabrication and reactors

    International Nuclear Information System (INIS)

    A total of four papers is presented. The first contribution of the Federal Republic of Germany reviews the market situation for reactors and the relations between reactor producers and buyers as reflected in sales agreements. The second West German contribution gives a world-wide survey of fuel element production as well as of fuel and fuel element demand up to the year 2000. The Canadian paper discusses the future prospects of heavy-water production, while the Ecuador contribution deals with small and medium-sized nuclear power plants

  14. The spectrographic analysis of inorganic impurities in heavy water

    International Nuclear Information System (INIS)

    Inorganic impurities in heavy water are determined by two spectrographic methods. First is described the copper-spark method which is sensitive and directly applicable, and is particular useful because of the absence of a support. Secondly the graphite impregnation method is given; this is used when the first method is not applicable (determination of copper) and for the alkali metals. For the usual elements, the sensitivity of the copper spark method is of the order of 0,1 μg/ml whereas for the graphite impregnation method the sensitivity is only 0,3 μg/ml. (author)

  15. Safety system in a heavy water detritiation plant

    International Nuclear Information System (INIS)

    In the heavy water circuits of the CANDU reactor, tritium is generated through the following reactions: - neutron activation; - 235 U, 233 U and 239 Pu fission in rods; - 3 He decay. The equilibrium value, of about 30-50 Ci/kg, depends by the heavy water quantity which is used in common in primary circuit and moderator, at an increase rate by 4Ci/kg/year. As the tritium inventory in a CANDU reactor can be larger than 6 x 106 Ci (tritium oxide in heavy water circuits), it results that a detritiation plant is a necessity. Solving these problems means that a heavy water detritiation plant must built and linked to the moderator circuits of the CANDU type reactor. This plant can be assimilated as a nuclear facility, involving special regulation and safety systems, complying with the nuclear laws of Romania and international safety regulations, including IAEA Vienna specifications. Like any nuclear facility, a special safety system is provided, with special hardware and software that supervises the technological process and safety equipment. Conventional systems use a large number of equipment, very expensive, while the reliability and accuracy are basic demands. On the other hand, the systems become more complex solving demands like redundancy, failure of safety or diversity. Like a result, operation and maintenance become more complicated and more expensive. Solution for these problems is to develop a reliable and flexible on-line diagnosis system, comprising two computers and a small number of discrete equipment. Creating a safety display and analysis system that provides an overview of the plant safety status and prevents serious safety degradation, ensures an easy maintenance and operation. The system is flexible, easy to use and the improvements needed by any technological process experiment could be done in short time and at low costs. Such a system can replace a dedicated hardware and software for industrial processes, regarding especially the experimental

  16. Construction management of Indian pressurized heavy water reactors

    International Nuclear Information System (INIS)

    Pandit Jawaharlal Nehru and Dr. Homi J. Bhabha, the visionary architects of Science and Technology of modern India foresaw the imperative need to establish a firm base for indigenous research and development in the field of nuclear electricity generation. The initial phase has primarily focused on the technology development in a systematic and structured manner, which has resulted in establishment of strong engineering, manufacturing and construction base. The nuclear power program started with the setting up of two units of boiling light water type reactors in 1969 for speedy establishment of nuclear technology, safety culture, and development of operation and maintenance manpower. The main aim at that stage was to demonstrate (to ourselves, and indeed to the rest of the world) that India, inspite of being a developing country, with limited industrial infrastructure and low capacity power grids, could successfully assimilate the high technology involved in the safe and economical operation of nuclear power reactors. The selection of a BWR was in contrast to the pressurized heavy water reactors (PHWR), which was identified as the flagship for the first stage of India's nuclear power program. The long-term program in three stages utilizes large reserves of thorium in the monazite sands of Kerala beaches in the third stage with first stage comprising of series of PHWR type plants with a base of 10,000 MW. India has at present 14 reactors in operation 12 of these being of PHWR type. The performance of operating units of 2720 MW has improved significantly with an overall capacity factor of about 90% in recent times. The construction work on eight reactor units with installed capacity of 3960 MW (two PHWRs of 540 MW each, four PHWRs of 220 MW each and two VVERs of 1000 MW each) is proceeding on a rapid pace with project schedules of less than 5 years from first pour of concrete. This is being achieved through advanced construction technology and management. Present

  17. Fuel cycle options for light water reactors and heavy water reactors. Proceedings of a technical committee meeting

    International Nuclear Information System (INIS)

    In the second half of the 20th century nuclear power has evolved from the research and development environment to an industry that supplies 16% of the world's electricity. By the end of 1997, over 8500 reactor-years of operating experience had been accumulated. Global environmental change, and the continuing increase in global energy supply required to provide increasing populations with an improving standard of living, make the contribution from nuclear energy even more important for the next century. For nuclear power to achieve its full potential and make its needed contribution, it must be safe, economical, reliable and sustainable. All of these factors can be enhanced by judicious choice and development of advanced fuel cycle options. The Technical Committee Meeting (TCM) on Fuel Cycle Options for Light Water Reactors and Heavy Water Reactors was hosted by Atomic Energy of Canada Limited (AECL) on behalf of the Canadian Government and was jointly conducted within the frame of activities of the IAEA International Working Group on Advanced Technologies for Light Water Reactors (IWG-LWR) and the IAEA International Working Group on Advanced Technologies for Heavy Water Reactors (IWG-HWR). The TCM provided the opportunity to have in-depth discussions on important technical topics which were highlighted in the International Symposium on Nuclear Fuel Cycle and Reactor Strategies: Adjusting to New Realities, held in Vienna, 3-6 June 1997. The main results and conclusions of the TCM were presented as input for discussion at the first meeting of the IAEA newly formed International Working Group on Fuel Cycle Options

  18. Water conservation by 3 R's - case histories of Heavy Water Plants

    International Nuclear Information System (INIS)

    The basics of water conservation revolve around three R's of Reduce, Recycle, and Reuse. The Heavy Water Plants are an excellent example of water savings, and these case studies will be of interest to the chemical industry. The issues involved with water conservation and re-use in different Heavy Water Plants are of different nature. In H2S-H2O process plants the water consumption has been substantially decreased as compared to the design water needs. To quote the figures HWP (Kota) was designed to consume 2280 m3/hr water, which included 453 m3/hr water as feed for deuterium extraction. Today the plant operates with only 1250 m3/hr water while processing 500 m3/hr feed; and is headed to decrease the total water consumption to 700 m3/hr. Similarly at HWP (Manuguru) the design had provided 5600 m3/hr water consumption, which is today operating with only 1750 m3/hr and poised to operate with 1600 m3/hr. The issues of water conservation in Ammonia Hydrogen exchange plants have an additional dimension since water losses mean direct loss of heavy water production. In adjoining ammonia plants deuterium shifts to steam in the reformer and shift converter, and this excess steam is condensed as rich condensate. It becomes incumbent on the fertilizer plant to maintain a tight discipline for conserving and re-using the rich condensate so that deuterium concentration in the synthesis gas is maintained. Efforts are also underway to utilize rich condensate of GSFC in the newly developed technology of water ammonia exchange at HWP (Baroda) and we are targeting 20% production gains by implementation of this scheme and with no increase in the pollution load. These case histories will be of interest to Chemical Process Industry. (author)

  19. Outline of advanced boiling water reactor

    International Nuclear Information System (INIS)

    The ABWR (Advanced Boiling Water Reactor) is based on construction and operational experience in Japan, USA and Europe. It was developed jointly by the BWR supplieres, General Electric, Hitachi, and Toshiba, as the next generation BWR for Japan. The Tokyo Electric Power Co. provided leadership and guidance in developing the ABWR, and in combination with five other Japanese electric power companies. The major objectives in developing the ABWR are: 1. Enhanced plant operability, maneuverability and daily load-following capability; 2. Increased plant safety and operating margins; 3. Improved plant availability and capacity factor; 4. Reduced occupational radiation exposure; 5. Reduced radwaste volume, and 6. Reduced plant capital and operating costs. (Liu)

  20. Human error - Risk factor in operating heavy water production facilities

    International Nuclear Information System (INIS)

    Continued increasing of the operating security of heavy water production facilities was and continues to be a basic preoccupation of the reliability specialists. According to statistical records about 20-30% of the failures occurred in such installations are directly or indirectly related to human errors. These are caused mainly by incorrect actions, maintenance errors, incorrect reading out of instrument indications. Not all the human errors have an impact on the system. A human error can be remedied before the undesirable consequences occur. Treating the human performances in probabilistic analytical studies provides the possibility of evaluating the human error contribution to the occurrence of event sequences. This work presents the possibility of utilizing probabilistic methods (event trees, failure trees) to identify solutions of improving the human reliability as far as the aspect of minimizing the risks in industrial installation operation is concerned. Also, different types of human errors were defined as well as the causes leading to committing mistakes, while, as technique for evaluating the human reliability, the method of decision tree analysis is presented. Exemplification for application of the method of human error analysis was made on the basis of operational data from the heavy water production pilot plant at Valcea, Romania. As initiation event for the accident situation the event of steam supply failure was considered. The contribution of human errors was analyzed for the accident sequence with the most serious consequences

  1. Concentration and speciation of heavy metals during water hyacinth composting.

    Science.gov (United States)

    Singh, Jiwan; Kalamdhad, Ajay S

    2012-11-01

    The Tessier sequential extraction method was employed to investigate the changes in heavy metals speciation (Zn, Cu, Mn, Fe, Pb, Ni, Cd and Cr) during water hyacinth (Eichhornia crassipes) composting. Results showed that, the contents of total metals concentration were increased during the composting process. The largest proportion of metals was found in the residual fraction which was in more stable form and is consequently considered unavailable for plant uptake. Reducible and oxidizable fractions of Ni, Pb and Cd were not found in all trials during water hyacinth composting. The concentrations of Cu and Cd were very low comparative to the other metals, but the percentage of exchangeable and carbonate fractions were similar as other metals. From this study it can be concluded that the appropriate proportion of cattle manure addition (Trial 4) significantly reduced the mobile and easily available fractions (exchangeable and carbonate fractions) during the composting process. PMID:22989643

  2. Heavy Liquid Metal Corrosion of Structural Materials in Advanced Nuclear Systems

    Science.gov (United States)

    Caro, M.; Woloshun, K.; Rubio, F.; Maloy, S. A.; Hosemann, P.

    2013-08-01

    Interest in advanced nuclear concepts using liquid metal coolant has increased in the past few years. Liquid metal coolants have been proposed for the next generation of small-sized nuclear reactors, which offer exceptional safety and reliability, sustainability, nonproliferation, and economic competitiveness. Heavy liquid metal coolants are investigated for advanced fast reactors that operate at high temperatures, reaching high efficiencies. Lead and lead-bismuth eutectic (LBE) coolants are also proposed as coolants and targets of accelerator driven systems. High temperature, corrosive environment, high fast neutron flux, high fluence, and radiation damage, among other physical phenomena, challenge the integrity of materials in these advanced systems. Excellent compatibility with the liquid coolant is recognized as a key factor in the selection of structural materials for advanced concepts. In this article, we review materials requirements for heavy metal cooled systems with emphasis on lead and LBE materials corrosion properties. We describe experimental corrosion tests currently ongoing at the Los Alamos National Laboratory (LANL) Development of Lead Alloy Technical Applications (DELTA) loop. DELTA is a facility designed to study the long-term corrosive effects of LBE on structural materials under relevant conditions of chemistry, flow, and temperature. The research studies will provide data of corrosion rates and corrosion mechanisms in selected steel exposed to high velocity (above 2 m/s) in flowing LBE at 500°C. Fundamental research studies will help support conceptual design efforts and further the development of heavy liquid metals technology.

  3. Treatment of Arsenazo III contaminated heavy water stored at Darlington

    International Nuclear Information System (INIS)

    Darlington Nuclear Generating Station (DNGS) has accumulated over 48 drums of chemistry laboratory waste arising from analysis of heavy water (D2O). Several organic, including Arsenazo III, and inorganic contaminants present in these drums results in high total organic carbon (TOC) and conductivity. These drums have not been processed due to uncertainties related to clean-up of Arsenazo III contaminated heavy water. This paper provides details of chemical characterization as well as bench scale studies performed to demonstrate the feasibility of treating the downgraded D2O to the stringent target specifications of <1 ppm TOC and <0.1mS/m conductivity, required for feed to the Station Upgrading Plant (SUP). Both ionic organic species such as glycolate, acetate and formate as well as neutral organics such as acetone, methanol and ethylene glycol were detected in all the samples. Morpholine and propylene glycol were detected in one sample. Arsenazo III was determined to be not a major contaminant (maximum 8.4 ppm) in these waste drums, compared to the other organic contaminants present. Various unit processes such as pH adjustment, granular activated carbon (GAC), ion exchange resin (IX), UV-peroxide oxidation (UV-H2O2) treatments, nanofiltration (NF) as well as reverse osmosis (RO) were tested on a bench scale both singly as well as in various combinations to evaluate their ability to achieve the stringent target conductivity and TOC specifications. Among the various bench scale tests evaluated, the successive processing train used at DNGS and consisting of GAC+IX+UV/H2O2+IX (polishing) unit operations was found to meet target specifications for both conductivity and TOC. Unit processes comprising (GAC+IX) and (RO-double pass + GAC+IX) met conductivity targets but failed to meet TOC specifications. The results of GAC+IX tests clearly emphasize the importance of using low flow rates for successful reduction in both conductivity as well as TOC. Detailed assessment of

  4. Treatment of Arsenazo III contaminated heavy water stored at Darlington

    Energy Technology Data Exchange (ETDEWEB)

    Suryanarayan, S.; Husain, A., E-mail: sriram.s@kinectrics.com [Kinectrics Inc., Toronto, Ontario (Canada); Williams, D., E-mail: denny.williams@opg.com [Ontario Power Generation, Darlington Nuclear Generating Station, Bowmanville, Ontario (Canada)

    2010-07-01

    Darlington Nuclear Generating Station (DNGS) has accumulated over 48 drums of chemistry laboratory waste arising from analysis of heavy water (D{sub 2}O). Several organic, including Arsenazo III, and inorganic contaminants present in these drums results in high total organic carbon (TOC) and conductivity. These drums have not been processed due to uncertainties related to clean-up of Arsenazo III contaminated heavy water. This paper provides details of chemical characterization as well as bench scale studies performed to demonstrate the feasibility of treating the downgraded D{sub 2}O to the stringent target specifications of <1 ppm TOC and <0.1mS/m conductivity, required for feed to the Station Upgrading Plant (SUP). Both ionic organic species such as glycolate, acetate and formate as well as neutral organics such as acetone, methanol and ethylene glycol were detected in all the samples. Morpholine and propylene glycol were detected in one sample. Arsenazo III was determined to be not a major contaminant (maximum 8.4 ppm) in these waste drums, compared to the other organic contaminants present. Various unit processes such as pH adjustment, granular activated carbon (GAC), ion exchange resin (IX), UV-peroxide oxidation (UV-H{sub 2}O{sub 2}) treatments, nanofiltration (NF) as well as reverse osmosis (RO) were tested on a bench scale both singly as well as in various combinations to evaluate their ability to achieve the stringent target conductivity and TOC specifications. Among the various bench scale tests evaluated, the successive processing train used at DNGS and consisting of GAC+IX+UV/H{sub 2}O{sub 2}+IX (polishing) unit operations was found to meet target specifications for both conductivity and TOC. Unit processes comprising (GAC+IX) and (RO-double pass + GAC+IX) met conductivity targets but failed to meet TOC specifications. The results of GAC+IX tests clearly emphasize the importance of using low flow rates for successful reduction in both conductivity as

  5. Heavy metal assessment and water quality values in urban stream and rain water

    International Nuclear Information System (INIS)

    Water quality monitoring in developing countries is inadequate, especially in stream water affected by urban effluents and runoff. The purpose of this study was to investigate heavy metal contaminants in the Nakivubo Stream water in Kampala, Uganda. Water samples Nakivubo Channelized Stream, tributaries and industrial effluents that drain into the stream were collected and analysed for the total elemental concentration using flame atomic absorption spectrophotometer. The results showed that: 1) the wastewater was highly enriched with lead and manganese above the maximum permissible limit; 2) the levels of dissolved oxygen were below the maximum permissible limit, while the biological oxygen demand was above the maximum permissible limit. All industrial effluents/wastewater were classified as strong (> 220 mg/L). Factor analysis results reveal two sources of pollutants; 1) mixed origin or chemical phenomena of industrial and vehicular emissions and 2) multiple origin of lead (vehicular, commercial establishment and industrial). In conclusion, Nakivubo Channelized Stream water is not enriched with heavy metals. These heavy metals (lead, cadmium and zinc) were rapidly removed by co-precipitation with manganese and iron hydroxides and total dissolved solids into stream sediments. This phenomena is controlled by p H in water.

  6. Pollution Status of Pakistan: A Retrospective Review on Heavy Metal Contamination of Water, Soil, and Vegetables

    Directory of Open Access Journals (Sweden)

    Amir Waseem

    2014-01-01

    Full Text Available Trace heavy metals, such as arsenic, cadmium, lead, chromium, nickel, and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. In addition to these metals, copper, manganese, iron, and zinc are also important trace micronutrients. The presence of trace heavy metals in the atmosphere, soil, and water can cause serious problems to all organisms, and the ubiquitous bioavailability of these heavy metal can result in bioaccumulation in the food chain which especially can be highly dangerous to human health. This study reviews the heavy metal contamination in several areas of Pakistan over the past few years, particularly to assess the heavy metal contamination in water (ground water, surface water, and waste water, soil, sediments, particulate matter, and vegetables. The listed contaminations affect the drinking water quality, ecological environment, and food chain. Moreover, the toxicity induced by contaminated water, soil, and vegetables poses serious threat to human health.

  7. Pollution status of Pakistan: a retrospective review on heavy metal contamination of water, soil, and vegetables.

    Science.gov (United States)

    Waseem, Amir; Arshad, Jahanzaib; Iqbal, Farhat; Sajjad, Ashif; Mehmood, Zahid; Murtaza, Ghulam

    2014-01-01

    Trace heavy metals, such as arsenic, cadmium, lead, chromium, nickel, and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. In addition to these metals, copper, manganese, iron, and zinc are also important trace micronutrients. The presence of trace heavy metals in the atmosphere, soil, and water can cause serious problems to all organisms, and the ubiquitous bioavailability of these heavy metal can result in bioaccumulation in the food chain which especially can be highly dangerous to human health. This study reviews the heavy metal contamination in several areas of Pakistan over the past few years, particularly to assess the heavy metal contamination in water (ground water, surface water, and waste water), soil, sediments, particulate matter, and vegetables. The listed contaminations affect the drinking water quality, ecological environment, and food chain. Moreover, the toxicity induced by contaminated water, soil, and vegetables poses serious threat to human health. PMID:25276818

  8. Advanced ceramic cladding for water reactor fuel

    International Nuclear Information System (INIS)

    Under the US Department of Energy's Nuclear Energy Research Initiatives (NERI) program, continuous fiber ceramic composites (CFCCs) are being developed as cladding for water reactor fuel elements. The purpose is to substantially increase the passive safety of water reactors. A development effort was initiated in 1991 to fabricate CFCC-clad tubes using commercially available fibers and a sol-gel process developed by McDermott Technologies. Two small-diameter CFCC tubes were fabricated using pure alumina and alumina-zirconia fibers in an alumina matrix. Densities of approximately 60% of theoretical were achieved. Higher densities are required to guarantee fission gas containment. This NERI work has just begun, and only preliminary results are presented herein. Should the work prove successful, further development is required to evaluate CFCC cladding and performance, including in-pile tests containing fuel and exploring a marriage of CFCC cladding materials with suitable advanced fuel and core designs. The possibility of much higher temperature core designs, possibly cooled with supercritical water, and achievement of plant efficiencies ge50% would be examined

  9. Penn State advanced light water reactor concept

    International Nuclear Information System (INIS)

    The accident at Three Mile Island heightened concerns over the safety of nuclear power. In response to these concerns, a research group at the Pennsylvania State University (Penn State) undertook the conceptual design of an advanced light water reactor (ALWR) under sponsorship of the US Dept. of Energy (DOE). The design builds on the literally hundreds of years worth of experience with light water reactor technology. The concept is a reconfigured pressurized water reactor (PWR) with the capability of being shut down to a safe condition simply by removing all ac power, both off-site and on-site. Using additional passively activated heat sinks and replacing the pressurizer with a pressurizing pump system, the concept essentially eliminates the concerns of core damage associated with a total station blackout. Evaluation of the Penn State ALWR concept has been conducted using the EPRI Modular Modeling System (MMS). Results show that a superior response to normal operating transients can be achieved in comparison to the response with a conventional PWR pressurizer. The DOE-sponsored Penn State ALWR concept has evolved into a significant reconfiguration of a PWR leading to enhanced safety characteristics. The reconfiguration has touched a number of areas in overall plant design including a shutdown turbine in the secondary system, additional passively activated heat sinks, a unique primary side pressurizing concept, a low pressure cleanup system, reactor building layout, and a low power density core design

  10. A Review of Laboratory-Scale Research on Upgrading Heavy Oil in Supercritical Water

    OpenAIRE

    Ning Li; Bo Yan; Xian-Ming Xiao

    2015-01-01

    With the growing demand for energy and the depletion of conventional crude oil, heavy oil in huge reserve has attracted extensive attention. However, heavy oil cannot be directly refined by existing processes unless they are upgraded due to its complex composition and high concentration of heteroatoms (N, S, Ni, V, etc.). Of the variety of techniques for heavy oil upgrading, supercritical water (SCW) is gaining popularity because of its excellent ability to convert heavy oil into valued, clea...

  11. Antineutrino monitoring for the Iranian heavy water reactor

    CERN Document Server

    Christensen, Eric; Jaffke, Patrick; Shea, Thomas

    2014-01-01

    In this note we discuss the potential application of antineutrino monitoring to the Iranian heavy water reactor at Arak, the IR-40, as a non-proliferation measure. We demonstrate that an above ground detector positioned right outside the IR-40 reactor building could meet and in some cases significantly exceed the verification goals identified by IAEA for plutonium production or diversion from declared inventories. In addition to monitoring the reactor during operation, observing antineutrino emissions from long-lived fission products could also allow monitoring the reactor when it is shutdown. Antineutrino monitoring could also be used to distinguish different levels of fuel enrichment. Most importantly, these capabilities would not require a complete reactor operational history and could provide a means to re-establish continuity of knowledge in safeguards conclusions should this become necessary.

  12. Reliability analysis of Indian pressurized heavy water reactor piping

    International Nuclear Information System (INIS)

    In this paper, a probabilistic analysis of primary heat transport of Indian Pressurized Heavy Water reactor is presented. The probability of failure of the straight pipes with through wall circumferential flaws subjected to bending moment is calculated. The failure criteria considered is net section collapse and R6 method. Probability of failure is obtained with crack growth initiation as the limiting condition. The variability in the crack size and material properties (tensile and fracture) is considered. The probability of failure is calculated at different levels of applied load. Various methods of probability estimation are presented and their equivalence is demonstrated. The probability of failure is obtained using classical Monte Carlo method, Monte Carlo with importance sampling, First Order Reliability Method (FORM), Second Order Reliability Method (SORM) and by numerical integration of the failure integral using Lepage's VEGAS algorithm. The results are utilized for demonstrating that for the leakage size crack, the pipe design has high probability for leak before break. (orig.)

  13. Planning for the decommissioning of a heavy water research reactor

    International Nuclear Information System (INIS)

    The Heavy Water Research Reactor (HWRR) was constructed and put into operation in 1958 at the China Institute of Atomic Energy (CIAE), located in the suburbs of Beijing. It was the first nuclear reactor in China. The HWRR is a 10 MW multipurpose research reactor and has been operated for 48 years. Because of its long operating history and aged equipment, it is scheduled to be finally shut down by the end of 2007. It has been decided by CIAE to implement a strategy of immediate dismantling after final shutdown. The paper describes the preparation work for the development of the HWRR decommissioning plan at CIAE. The establishment and organization of the project and the problems encountered are described. Progress and problems are addressed. The paper also discusses the measures needed for the successful planning of decommissioning. (author)

  14. Simulation and optimal operation of a heavy water upgrader plant

    International Nuclear Information System (INIS)

    The paper presents the computer programs elaborated to determine the efficiency of D2 O upgrader plant from Cernavoda NPP and its optimum operating by the right choosing of the feed location of top bottom extraction flow rate for a given reflux. The software is currently used in the operation of the moderator and thermal agent upgrader's systems of the first reactor CANDU in commercial operation in Romania. Since the programs run under Windows operating environment there are many advantages: user friendly graphic interface, easy work with the menus and the dialogue windows, the use of the mouse, the work with different printers and error messages. This software is useful also for who is operating with heavy water final rectification facility using under vacuum distillation in large plants which produce nuclear material. For easy visualization of the results, OPTREC program can display the plant scheme with input and output data (flow rates, concentrations, optimum feed data , etc). (authors)

  15. Heavy-water-moderated pressure-tube reactor safety

    International Nuclear Information System (INIS)

    Several countries have heavy-water-moderated, pressure-tube reactors either in commercial operation or in late prototype stages. The supporting safety research and development includes such areas as the thermohydraulics of circuit depressurization, heat transfer from the fuel, heat rejection to the moderator from dry fuel, fuel and sheath behaviour, and fuel channel integrity. We review the work done in Canada, Great Britain, Italy and Japan, and describe some of the experimental tests underlaying the methods of accident analysis. The reactors have safety systems which, in the event of an accident, are able to shut down the reactor, keep the fuel cooled, and contain any released radioactivity. We summarize the characteristics of these safety systems (shutdown, emergency core cooling, and containment) in the various reactors, and discuss other reactor characteristics which either prevent accidents or reduce their potential demand on the safety systems. (author)

  16. Use of dried ion exchange resin for heavy water system

    International Nuclear Information System (INIS)

    In order to prevent degradation of D2O in HANARO reflector system due to the moisture in the ion exchange resin, a method using the dried resin is developed. The physical change of dried resin was observed and measured. The performance was tested, and verified. The moisture content in the resin could be reduced to below 1% from its original content of about 55%. The integrated degradation of D2O for 20 years is estimated as 0.23% if the dried resin is used whenever it is replaced. This is much simpler process than the deuteration method which has been used in the other facilities such as heavy water reactors, and the cost of which is almost negligible. Should the dried resin be used for an existing deuteration facility, the generation of degraded D2O will be significantly reduced

  17. Accounting Systems for Heavy Water and Fissionable Materials

    International Nuclear Information System (INIS)

    Detailed accounting and reporting procedures used by Atomic Energy of Canada Limited (AECL) for maintaining adequate records and control of heavy water supplies and stocks of fissionable materials are described, along with the duties and responsibilities of those administering the system. An appraisal is made of these procedures with respect to their adaptability for use in rapidly expanding research and power programmes. In particular the use of electronic data processing equipment is evaluated. A senior management committee is responsible for ensuring that there is a proper system for recording, reporting and controlling fissionable materials. The Production Planning and Control Branch (Pp and C B) of the Operations Division at the Chalk River Nuclear Laboratories (CRNL) is responsible to the committee for keeping the over-all records and for the general administration of the system. The duties involved are detailed in the report. The system for fissionable materials is segregated into several accountability units 15 of which are allocated to AECL departments and the others to Canadian industries and research organizations. A control ledger is kept by PP and CB for each of the units; however, the units are responsible for preparing detailed accounts of all material under their jurisdiction. The basic recording procedures covering the movement Of materials between units, the changing of forms within units, the handling of gains and losses, and disposals, are outlined in the report. The transfer of this data to IBM cards, the ultimate processing through an IBM 1401 computer and the preparation of reports for management approval are described. The heavy-water accounting system based on the same principles as used for the fissionable materials is explained. In this case the control ledger lists the pounds of D2O allocated to each of the 15 accountability units. Again the basic recording methods and the use of a computer system are outlined. (author)

  18. Advanced applications of water cooled nuclear power plants

    International Nuclear Information System (INIS)

    By August 2007, there were 438 nuclear power plants (NPPs) in operation worldwide, with a total capacity of 371.7 GW(e). Further, 31 units, totaling 24.1 GW(e), were under construction. During 2006 nuclear power produced 2659.7 billion kWh of electricity, which was 15.2% of the world's total. The vast majority of these plants use water-cooled reactors. Based on information provided by its Member States, the IAEA projects that nuclear power will grow significantly, producing between 2760 and 2810 billion kWh annually by 2010, between 3120 and 3840 billion kWh annually by 2020, and between 3325 and 5040 billion kWh annually by 2030. There are several reasons for these rising expectations for nuclear power: - Nuclear power's lengthening experience and good performance: The industry now has more than 12 000 reactor years of experience, and the global average nuclear plant availability during 2006 reached 83%; - Growing energy needs: All forecasts project increases in world energy demand, especially as population and economic productivity grow. The strategies are country dependent, but usually involve a mix of energy sources; - Interest in advanced applications of nuclear energy, such as seawater desalination, steam for heavy oil recovery and heat and electricity for hydrogen production; - Environmental concerns and constraints: The Kyoto Protocol has been in force since February 2005, and for many countries (most OECD countries, the Russian Federation, the Baltics and some countries of the Former Soviet Union and Eastern Europe) greenhouse gas emission limits are imposed; - Security of energy supply is a national priority in essentially every country; and - Nuclear power is economically competitive and provides stability of electricity price. In the near term most new nuclear plants will be evolutionary water cooled reactors (Light Water Reactors (LWRs) and Heavy Water Reactors (HWRs), often pursuing economies of scale. In the longer term, innovative designs that

  19. Fuel behavior in advanced water reactors

    International Nuclear Information System (INIS)

    Fuel rod behavior of advanced pressurized water reactors under steady state conditions has been investigated in this study. System-80+ and Westinghouse Vantage-5 fuels have been considered as advanced pressurized water reactor fuels to be analyzed. The purpose of this study is to analyze the sensitivity of ditferent models and the effect of selected design parameters on the overall fuel behavior. FRAPCON-II computer code has been used for the analyses. Different modelling options of FRAPCON-II have also been considered in these analyses. Analyses have been performed in two main parts. In the first part, effects of operating conditions on fuel behavior have been investigated. First, fuel rod response under normal operating conditions has been analyzed. Then, fuel rod response to different fuel ratings has been calculated. In the second part, in order to estimate the effect of design parameters on fuel behavior, parametric analyses have been performed. In this part, the effects of initial gap thickness, as fabricated fuel density, and initial fill gas pressure on fuel behavior have been analyzed. The computations showed that both of the fuel rods used in this study operate within the safety limits. However, FRAPCON-II modelling options have been resulted in different behavior due to their modelling characteristics. Hence, with the absence of experimental data, it is difficult to make assesment for the best fuel parameters. It is also difficult to estimate error associated with the results. To improve the performance of the code, it is necessary to develop better experimental correlations for material properties in order to analyze the eftect ot considerably different design parameters rather than nominal rod parameters

  20. Heavy metal contaminations of soil and water at the Magdeburger waste water irrigation fields and the consequences for future utilization

    International Nuclear Information System (INIS)

    As a result of the continued application of municipal waste water on the sewage irrigation fields of Magdeburg the top soil has accumulated large amounts of heavy metals. In the view of ecology the heavy metal pollution caused by irrigating pretreated waste water must be considered very high. Investigation results are presented, model calculations of the heavy metal accumulation on the sewage irrigation fields are carried out and the possibilities of future soil utilization are discussed. (orig.)

  1. Studies on corrosion inhibitors for the cooling water system at the Heavy Water Project, Kota

    International Nuclear Information System (INIS)

    The Heavy Water Project at Kota uses the water from the Rana Pratap Sagar Lake as coolant in the open recirculation system. In order to find suitable corrosion inhibitors for the above system, a series of laboratory experiments on corrosion inhibitors were carried out using the constructional materials of the cooling water system and a number of proprietary formulations and the results are tabulated. From the data thus generated through various laboratory experiments, the most useful ones have been recommended for application in practice. (author)

  2. Experimental study of flow patterns and pressure drops of heavy oil-water-gas vertical flow

    Institute of Scientific and Technical Information of China (English)

    LIU Xi-mao; ZHONG Hai-quan; LI Ying-chuan; LIU Zhong-neng; WANG Qi

    2014-01-01

    A stainless steel apparatus of 18.5 m high and 0.05 m in inner diameter is developed, with the heavy oil from Lukeqin Xinjiang oil field as the test medium, to carry out the orthogonal experiments for the interactions between heavy oil-water and heavy oil-water-gas. With the aid of observation windows, the pressure drop signal can be collected and the general multiple flow patterns of heavy oil-water-gas can be observed, including the bubble, slug, churn and annular ones. Compared with the conventional oil, the bubble flows are identified in three specific flow patterns which are the dispersed bubble (DB), the bubble gas-bubble heavy oil go(B-B), and the bubble gas-intermittent heavy oilgo(B-I). The slug flows are identified in two specific flow patterns which are the intermittent gas-bubble heavy oilgo(I-B)and the intermittent gas-intermittent heavy oilgo(I-I). Compared with the observa- tions in the heavy oil-water experiment, it is found that the conventional models can not accurately predict the pressure gradient. And it is not water but heavy oil and water mixed phase that is in contact with the tube wall. So, based on the principle of the energy con- servation and the kinematic wave theory, a new method is proposed to calculate the frictional pressure gradient. Furthermore, with the new friction gradient calculation method and a due consideration of the flow characteristics of the heavy oil-water-gas high speed flow, a new model is built to predict the heavy oil-water-gas pressure gradient. The predictions are compared with the experiment data and the field data. The accuracy of the predictions shows the rationality and the applicability of the new model.

  3. RHEOLOGICAL BEHAVIOR OF WATER-IN-OIL EMULSIONS OF HEAVY AND EXTRA-HEAVY LIVE OILS: EXPERIMENTAL EVALUATION

    OpenAIRE

    Libia-Sofia Sandoval-Rodríguez; Wilson A Cañas-Marín; Ramiro Martínez-Rey

    2014-01-01

    Stable emulsions were prepared with heavy and extra-heavy live oils by using a set-up recently built at Ecopetrol S.A. - Instituto Colombiano del Petróleo (ICP). This equipment permits to prepare water-in-oil emulsions at reservoir conditions without any change on the overall hydrocarbon composition. The live emulsions were prepared with water contents up to 26% in volume. Then, a capillary viscometer was used to study the rheological behavior of these emulsions at different shear rates and p...

  4. Heavy water in the context of hydrogen economy. Prospects for cheaper production by water electrolysis

    International Nuclear Information System (INIS)

    Hydrogen is an extremely important material. It is commonly used in many industrial processes. It can also be used as the key medium in 'hydrogen energy philosophy' due to its unique energetic properties (production for storage, gas-line transport). Its heavy isotopes, deuterium (D) and tritium (T), are very important nuclear materials. Deuterium, in the form of heavy water, is an excellent moderator in fission reactors, while both D and T are now seen as fuel components in fusion reactors in the future. Thus, improvements of production processes for hydrogen and its isotopes are always actual. Electrolysis (sometimes in combination with other methods) is often used for heavy water production or re-enrichment or for tritium removal from 'nuclear waters', mostly because of high D/H (T/H, T/D) isotope separation factors, although the electrolysis consumes great amounts of energy (about 4.5 to 5 kWh/m3 H2 in industrial electrolyzers). There were various attempts to improve this process: zero-gap cell geometry, development of new diaphragm materials, development of new electrocatalytic materials for electrodes, using so-called ionic activators etc. We investigated the use of catalytic cathode materials made from hypo-hyper-d-electronic combinations of transition metals as well as in situ activation of electrodes. Many intermetallic combinations were tried. Two types of ionic activators were used: tris-(ethylenediamine)-Co(III)-chloride complex and tris-(trimethylenediamine)-Co(III)-chloride complex. Some significant increases of the separation factors were obtained. Dependence of isotope enrichment on the amount of water that must be electrolysed for was estimated for different values of the separation factor. It was concluded that this a good way to increase the efficiency of the process by achieving an energy saving and an increase of the separation factors simultaneously. The method is discussed in a context that assumes heavy water as a by-product of the hydrogen

  5. Report on the state of heavy water system during distillation - Annex 8

    International Nuclear Information System (INIS)

    Measurements of radiation level were done in 7 points of the heavy water system and distillation system. Measuring results shown in this report show that the radiation intensity was highest on the heat exchangers and lowest on the incoming pipe at the heavy water distillation system

  6. Programmable logic controllers in Heavy Water Project, Manuguru (Paper No. 3.4)

    International Nuclear Information System (INIS)

    Enhancement to plant operational flexibility has been achieved in Heavy Water Project, Manuguru by installing programmable logic controllers for its control equipment. The earlier sulfide based Heavy Water Plant, Kota is using relay logic and diode based program-matrix for binary controls. Performance improvement and advantages of PLC and experience in its operation are described. (author). 3 refs

  7. Tritium separation from light and heavy water by bipolar electrolysis

    International Nuclear Information System (INIS)

    Use of bipolar electrolysis with countercurrent electrolyte flow to separate hydrogen isotopes was investigated for the removal of tritium from light water effluents or from heavy water moderator. Deuterium-tritium and protium-tritium separation factors occurring on a Pd-25% Ag bipolar electrode were measured to be 2.05 to 2.16 and 11.6 to 12.4 respectively, at current densities between 0.21 and 0.50 A cm-2, and at 35 to 900C. Current densities up to 0.3 A cm-2 have been achieved in continuous operation, at 80 to 900C, without significant gas formation on the bipolar electrodes. From the measured overvoltage at the bipolar electrodes and the electrolyte conductivity the power consumption per stage was calculated to be 3.0 kwh/kg H2O at 0.2 A cm-2 and 5.0 kwh/kg H2O at 0.5 A cm-2 current density, compared to 6.4 and 8.0 kwh/kg H2O for normal electrolysis. A mathematical model derived for hydrogen isotope separation by bipolar electrolysis, i.e., for a square cascade, accurately describes the results for protium-tritium separation in two laboratory scale, multistage experiments with countercurrent electrolyte flow; the measured tiritum concentration gradient through the cascade agreed with the calculated values

  8. Increasing the reliability of electric energy supply to consumers in ROMAG-PROD Heavy Water Plant

    International Nuclear Information System (INIS)

    Full text: This work aims at achieving an analysis of time evolution of the status of electrical installations, their performances and reliability, at describing the refurbishment measures adopted, at assessing the efficiency of these measures and also to suggest solutions for improving the reliability in the electric energy supply of ROMAG-PROD Heavy Water Plant. The analysis started from the original design, the manner the electrical installations were mounted, the technological level of this equipment and gives an evaluation of the deficiencies and the evolution of incidents occurred during the operation period. On the basis of the experience gathered one advances new items for equipment renewing and refurbishment of electric installations which together with the existing ones would ensure an electric energy supply more secure and efficient, leading directly to a more safe and efficient operation of the ROMAG-PROD Heavy Water Plant. In this work the incidents of electric energy nature which occurred are analyzed, the equipment which generated events identified and measures to solve these problems proposed

  9. SIEL: heavy water inventory system (Systeme d'Inventaire d'Eau Lourde)

    International Nuclear Information System (INIS)

    Heavy water is a very expensive resource and is also a prescribed material according to the Canadian Nuclear Safety Commission (CNSC). Since the commissioning of the CANDU-6 PHWR at Gentilly-2 in 1983, extensive efforts have been deployed to achieve effective and accurate heavy water management. Unfortunately, the tools available and the methods used in the beginning resulted in considerable uncertainties in the heavy water inventory after only a few months of operation. Since that time, improving heavy water management has always been a constant challenge and a goal. For these reasons, we developed an efficient, practical and modern new tool. SIEL is the result of the combination of all those experiences, successes, and failures acquired at G-2 over the years in D2O management, and of the new technologies now available. The main purpose of SIEL is to easily track the heavy water inventory and losses on a daily basis. (author)

  10. Progress in the Development of a Heavy-Water Moderated and Cooled Thorium-Uranium-233 Converter

    International Nuclear Information System (INIS)

    On account of its excellent neutron economy the heavy-water reactor is suitable for development as a high-gain converter or as a breeder in the thorium-uranium-233 cycle. In the Federal Republic of Germany work on these lines is being carried out at the Jülich Nuclear Research Centre in co-operation with the Siemens Company. Prominence is being given to a pressure-vessel reactor moderated and cooled by heavy water. Contrary to natural uranium types the thorium reactor will have a quasi-homogeneous core structure and a much lower heavy-water content and therefore will be in appearance more similar to a light-water reactor. With a quasi-homogeneous lattice and the fact that flux peaks are more easily avoided in a D2O core than in an H2O one, the mean specific fuel power (which is decisive for the economic efficiency of a thorium reactor) attains a higher value than in reactors with clustered fuel elements or in light-water reactors. The D2O-thorium reactor will have core power densities in the range of those attained in boiling light-water reactors. This power density is greater than in any other advanced converter. Development work can be based on the well-known technology of water-cooled reactors and on operating experience with the multipurpose reactor (MZFR) at Karlsruhe. The total time and cost required for the development of the heavy-water reactor towards a thorium-uranium-converter or breeder is therefore relatively small. This type will profit in particular from the great progress made in recent years with Zircaloy-canned ceramic fuel rods and with fuel element development. At minimum fuel cycle costs in the range of 1 mill/kWh, including costs for D2O inventory, the specific consumption of 235U for maintaining a reprocessed equilibrium cycle is calculated to be 0.20 g 235U/MWd, including diffusion tails. Calculation methods are shown to be in good agreement with lattice experiments carried out in the Siemens Argonaut Reactor at Garching. On account of the

  11. Production of heavy water. An analysis from export control point of view

    International Nuclear Information System (INIS)

    The main use for heavy water is in heavy water moderated nuclear reactors. This type of reactor is optimal for producing plutonium and therefore countries with nuclear weapons ambitions show interest for such reactors. Most equipment used in heavy water production facilities are under export control to prevent clandestine heavy water production. Heavy water is produced by increasing the concentration of deuterium in the water relative to natural hydrogen. For use in nuclear reactors the deuterium content has to be increased from 0,0155 % to more than 99,75 %. The enrichment can be achieved by several different processes where the GS-process (hydrogen-sulphide exchange) and ammonia-hydrogen exchange process are the two most cost efficient. The energy consumption for these processes is however relatively high. This is due to low separation efficiency which is caused by the relatively small difference in chemical properties between heavy water and natural water. FOI has, under contract work financed by SKI, performed a study of different production processes for heavy water and identified equipment used in the processes. The identified equipment includes both equipment under export control and other sensitive equipment which is important to prevent countries with nuclear weapons ambitions to acquire

  12. Plant life management processes and practices for heavy water reactors

    International Nuclear Information System (INIS)

    In general, heavy water reactor (HWR) nuclear power plant (NPP) owners would like to keep their NPPs in service as long as they can be operated safely and economically. Their decisions are depending on essentially business model. They involve the consideration of a number of factors, such as the material condition of the plant, comparison with current safety standards, the socio-political climate and asset management/ business planning considerations. Continued plant operation, including operation beyond design life, called 'long term operation, depends, among other things, on the material condition of the plant. This is influenced significantly by the effectiveness of ageing management. Key attributes of an effective plant life management program include a focus on important systems, structure and components (SSCs) which are susceptible to ageing degradation, a balance of proactive and reactive ageing management programmes, and a team approach that ensures the co-ordination of and communication between all relevant nuclear power plant and external programmes. Most HWR NPP owners/operators use a mix of maintenance, surveillance and inspection (MSI) programs as the primary means of managing ageing. Often these programs are experienced-based and/or time-based and may not be optimised for detecting and/or managing ageing effects. From time-to-time, operational history has shown that this practice can be too reactive, as it leads to dealing with ageing effects (degradation of SSCs) after they have been detected. In many cases premature and/or undetected ageing cannot be traced back to one specific reason or an explicit error. The root cause is often a lack of communication, documentation and/or co-ordination between design, commissioning, operation or maintenance organizations. This lack of effective communication and interfacing frequently arises because, with the exception of major SSCs, such as the fuel channels or steam generators, there is a lack of explicit

  13. Accident analysis of heavy water cooled thorium breeder reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yulianti, Yanti [Department of Physics, University of Lampung Jl. Sumantri Brojonegoro No.1 Bandar Lampung, Indonesia Email: y-yanti@unila.ac.id (Indonesia); Su’ud, Zaki [Department of Physics, Bandung Institute of Technology Jl. Ganesha 10 Bandung, Indonesia Email: szaki@fi.itb.ac.id (Indonesia); Takaki, Naoyuki [Department of Nuclear Safety Engineering Cooperative Major in Nuclear Energy (Graduate School) 1-28-1 Tamazutsumi,Setagayaku, Tokyo158-8557, Japan Email: ntakaki@tcu.ac.jp (Japan)

    2015-04-16

    Thorium has lately attracted considerable attention because it is accumulating as a by-product of large scale rare earth mining. The objective of research is to analyze transient behavior of a heavy water cooled thorium breeder that is designed by Tokai University and Tokyo Institute of Technology. That is oxide fueled, PWR type reactor with heavy water as primary coolant. An example of the optimized core has relatively small moderator to fuel volume ratio (MFR) of 0.6 and the characteristics of the core are burn-up of 67 GWd/t, breeding ratio of 1.08, burn-up reactivity loss during cycles of < 0.2% dk/k, and negative coolant reactivity coefficient. One of the nuclear reactor accidents types examined here is Unprotected Transient over Power (UTOP) due to withdrawing of the control rod that result in the positive reactivity insertion so that the reactor power will increase rapidly. Another accident type is Unprotected Loss of Flow (ULOF) that caused by failure of coolant pumps. To analyze the reactor accidents, neutron distribution calculation in the nuclear reactor is the most important factor. The best expression for the neutron distribution is the Boltzmann transport equation. However, solving this equation is very difficult so that the space-time diffusion equation is commonly used. Usually, space-time diffusion equation is solved by employing a point kinetics approach. However, this approach is less accurate for a spatially heterogeneous nuclear reactor and the nuclear reactor with quite large reactivity input. Direct method is therefore used to solve space-time diffusion equation which consider spatial factor in detail during nuclear reactor accident simulation. Set of equations that obtained from full implicit finite-difference method is solved by using iterative methods. The indication of UTOP accident is decreasing macroscopic absorption cross-section that results large external reactivity, and ULOF accident is indicated by decreasing coolant flow. The

  14. Accident analysis of heavy water cooled thorium breeder reactor

    International Nuclear Information System (INIS)

    Thorium has lately attracted considerable attention because it is accumulating as a by-product of large scale rare earth mining. The objective of research is to analyze transient behavior of a heavy water cooled thorium breeder that is designed by Tokai University and Tokyo Institute of Technology. That is oxide fueled, PWR type reactor with heavy water as primary coolant. An example of the optimized core has relatively small moderator to fuel volume ratio (MFR) of 0.6 and the characteristics of the core are burn-up of 67 GWd/t, breeding ratio of 1.08, burn-up reactivity loss during cycles of < 0.2% dk/k, and negative coolant reactivity coefficient. One of the nuclear reactor accidents types examined here is Unprotected Transient over Power (UTOP) due to withdrawing of the control rod that result in the positive reactivity insertion so that the reactor power will increase rapidly. Another accident type is Unprotected Loss of Flow (ULOF) that caused by failure of coolant pumps. To analyze the reactor accidents, neutron distribution calculation in the nuclear reactor is the most important factor. The best expression for the neutron distribution is the Boltzmann transport equation. However, solving this equation is very difficult so that the space-time diffusion equation is commonly used. Usually, space-time diffusion equation is solved by employing a point kinetics approach. However, this approach is less accurate for a spatially heterogeneous nuclear reactor and the nuclear reactor with quite large reactivity input. Direct method is therefore used to solve space-time diffusion equation which consider spatial factor in detail during nuclear reactor accident simulation. Set of equations that obtained from full implicit finite-difference method is solved by using iterative methods. The indication of UTOP accident is decreasing macroscopic absorption cross-section that results large external reactivity, and ULOF accident is indicated by decreasing coolant flow. The

  15. Accident analysis of heavy water cooled thorium breeder reactor

    Science.gov (United States)

    Yulianti, Yanti; Su'ud, Zaki; Takaki, Naoyuki

    2015-04-01

    Thorium has lately attracted considerable attention because it is accumulating as a by-product of large scale rare earth mining. The objective of research is to analyze transient behavior of a heavy water cooled thorium breeder that is designed by Tokai University and Tokyo Institute of Technology. That is oxide fueled, PWR type reactor with heavy water as primary coolant. An example of the optimized core has relatively small moderator to fuel volume ratio (MFR) of 0.6 and the characteristics of the core are burn-up of 67 GWd/t, breeding ratio of 1.08, burn-up reactivity loss during cycles of coolant reactivity coefficient. One of the nuclear reactor accidents types examined here is Unprotected Transient over Power (UTOP) due to withdrawing of the control rod that result in the positive reactivity insertion so that the reactor power will increase rapidly. Another accident type is Unprotected Loss of Flow (ULOF) that caused by failure of coolant pumps. To analyze the reactor accidents, neutron distribution calculation in the nuclear reactor is the most important factor. The best expression for the neutron distribution is the Boltzmann transport equation. However, solving this equation is very difficult so that the space-time diffusion equation is commonly used. Usually, space-time diffusion equation is solved by employing a point kinetics approach. However, this approach is less accurate for a spatially heterogeneous nuclear reactor and the nuclear reactor with quite large reactivity input. Direct method is therefore used to solve space-time diffusion equation which consider spatial factor in detail during nuclear reactor accident simulation. Set of equations that obtained from full implicit finite-difference method is solved by using iterative methods. The indication of UTOP accident is decreasing macroscopic absorption cross-section that results large external reactivity, and ULOF accident is indicated by decreasing coolant flow. The power reactor has a peak value

  16. Pulse radiolysis studies of liquid heavy water at temperatures up to 250 degrees C

    International Nuclear Information System (INIS)

    This report documents the rate constants and associated activation energies for the reactions of the primary radical species, eaq-, ·OD and ·D, which are formed during the radiolysis of heavy water within the temperature range 20 to 250 oC. These heavy-water data have been compared with the corresponding information for light water. These kinetic data form part of the database that is required to model the aqueous radiation chemistry that occurs within the core of the heavy water cooled and moderated CANDU reactor. (author)

  17. Surface Water Modeling Using an EPA Computer Code for Tritiated Waste Water Discharge from the heavy Water Facility

    International Nuclear Information System (INIS)

    Tritium releases from the D-Area Heavy Water Facilities to the Savannah River have been analyzed. The U.S. EPA WASP5 computer code was used to simulate surface water transport for tritium releases from the D-Area Drum Wash, Rework, and DW facilities. The WASP5 model was qualified with the 1993 tritium measurements at U.S. Highway 301. At the maximum tritiated waste water concentrations, the calculated tritium concentration in the Savannah River at U.S. Highway 301 due to concurrent releases from D-Area Heavy Water Facilities varies from 5.9 to 18.0 pCi/ml as a function of the operation conditions of these facilities. The calculated concentration becomes the lowest when the batch releases method for the Drum Wash Waste Tanks is adopted

  18. Selected bibliography on heavy water, tritiated water and hydrogen isotopes (1981-1992)

    Science.gov (United States)

    Gopalakrishnan, V. T.; Sutawane, U. B.; Rathi, B. N.

    A selected bibliography on heavy water, tritiated water and hydrogen isotopes is presented. This bibliography covers the period 1981-1992 and is in continuation to Division's earlier report BARC-1192 (1983). The sources of information for this compilation are Chemical Abstracts, INIS Atom Index and also some scattered search through journals and reports available in our library. No claim is made towards exhaustiveness of this bibliography even though sincere attempts have been made for a wide coverage. The bibliography is arranged under the headings: (1) production, purification, recovery, reprocessing and storage; (2) isotope exchange; (3) isotope analysis; (4) properties; and (5) miscellaneous. Total number of references in the bibliography are 1762.

  19. Selected bibliography on heavy water, tritiated water and hydrogen isotopes (1981-1992)

    International Nuclear Information System (INIS)

    A selected bibliography on heavy water, tritiated water and hydrogen isotopes is presented. This bibliography covers the period 1981-1992 and is in continuation to Division's earlier report BARC-1192 (1983). The sources of information for this compilation are Chemical Abstracts, INIS Atom Index and also some scattered search through journals and reports available in our library. No claim is made towards exhaustiveness of this bibliography even though sincere attempts have been made for a wide coverage. The bibliography is arranged under the headings: (1) production, purification, recovery, reprocessing and storage, (2) isotope exchange, 3) isotope analysis, (4) properties and (5) miscellaneous. Total number of references in the bibliography are 1762. (author)

  20. NATO Advanced Research Workshop on Ionization of Solids by Heavy Particles

    CERN Document Server

    1993-01-01

    This book collects the papers presented at the NATO Advanced Research Workshop on "Ionization of Solids by Heavy Particles", held in Giardini-Naxos (Taormina), Italy, on June 1 -5, 1992. The meeting was the first to gather scientists to discuss the physics of electron emission and other ionization effects occurring during the interaction of heavy particles with condensed matter. The central problem in the field is how to use observations of electron emission and final radiation damage to understand what happens inside the solid, like excitation mechanisms, the propagation of the electronic excitation along different pathways, and surface effects. The ARW began with a brief survey of the field, stressing the unknowns. It was pointed out that ionization theories can only address the very particular case of weak perturbations. For this problem, this meant high speed, low-charged projectiles (a perturbation treatment of interactions with slow, highly charged ions was later presented). Only semi-empirical ...

  1. Clean Cities Guide to Alternative Fuel and Advanced Medium- and Heavy-Duty Vehicles (Book)

    Energy Technology Data Exchange (ETDEWEB)

    2013-08-01

    Today's fleets are increasingly interested in medium-duty and heavy-duty vehicles that use alternative fuels or advanced technologies that can help reduce operating costs, meet emissions requirements, improve fleet sustainability, and support U.S. energy independence. Vehicle and engine manufacturers are responding to this interest with a wide range of options across a steadily growing number of vehicle applications. This guide provides an overview of alternative fuel power systems?including engines, microturbines, electric motors, and fuel cells?and hybrid propulsion systems. The guide also offers a list of individual medium- and heavy-duty vehicle models listed by application, along with associated manufacturer contact information, fuel type(s), power source(s), and related information.

  2. Clean Cities Guide to Alternative Fuel and Advanced Medium- and Heavy-Duty Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-08-01

    Today's fleets are increasingly interested in medium-duty and heavy-duty vehicles that use alternative fuels or advanced technologies that can help reduce operating costs, meet emissions requirements, improve fleet sustainability, and support U.S. energy independence. Vehicle and engine manufacturers are responding to this interest with a wide range of options across a steadily growing number of vehicle applications. This guide provides an overview of alternative fuel power systems--including engines, microturbines, electric motors, and fuel cells--and hybrid propulsion systems. The guide also offers a list of individual medium- and heavy-duty vehicle models listed by application, along with associated manufacturer contact information, fuel type(s), power source(s), and related information.

  3. Design improvements for pressurized heavy water reactors in Korea

    International Nuclear Information System (INIS)

    Three medium size (700 MWe class) CANDU (CANadian Deuterium Uranium) 6 Pressurized Heavy Water Reactors (PHWR) are currently under construction at Wolsong site in Korea by KEPCO (Korea Electric Power Corporation). KAERI (Korea Atomic Energy Research Institute) and AECL (Atomic Energy of Canada Limited) have jointly undertaken studies on incorporating improved design features and technology based on the operating plant experience. The improvements for future PHWRs in Korea was described and compared to the current CANDU 6 and other operating CANDU units. The CANDU 9 PHWR based on the single unit adaptation of Darlington plant operating in Canada with natural uranium fuel utilizes proven technology throughout. The reactor design has 480 fuel channels compared with 380 fuel channels for the CANDU 6 reactor. CANDU 9 design features can be further updated so that the Improved PHWR will meet evolving utility requirements in Korea. The Improved PHWR with a higher electrical output than CANDU 6 offers a number of advantages to utilities with compatible grid capacity. These include economy of scale in capital cost and operating cost. Future Improved PHWRs can further achieve a higher output by using recovered uranium or slightly enriched uranium. (author)

  4. Freezing of heavy water (D2O) nanodroplets.

    Science.gov (United States)

    Bhabhe, Ashutosh; Pathak, Harshad; Wyslouzil, Barbara E

    2013-07-01

    We follow the freezing of heavy water (D2O) nanodroplets formed in a supersonic nozzle apparatus using position resolved pressure trace measurements, Fourier transform infrared spectroscopy, and small-angle X-ray scattering. For these 3-9 nm radii droplets, freezing starts between 223 and 225 K, at volume based ice nucleation rates Jice,V on the order of 10(23) cm(-3) s(-1) or surface based ice nucleation rates Jice,S on the order of 10(16) cm(-2) s(-1). The temperatures corresponding to the onset of D2O ice nucleation are higher than those reported for H2O by Manka et al. [Manka, A.; Pathak, H.; Tanimura, S.; Wölk, J.; Strey, R.; Wyslouzil, B. E. Phys. Chem. Chem. Phys.2012, 14, 4505]. Although the values of Jice,S scale somewhat better with droplet size than values of Jice,V, the data are not accurate enough to state that nucleation is surface initiated. Finally, using current estimates of the thermophysical properties of D2O and the theoretical framework presented by Murray et al. [Murray, B. J.; Broadley, S. L.; Wilson, T. W.; Bull, S. J.; Wills, R. H.; Christenson, H. K.; Murray, E. J. Phys. Chem. Chem. Phys.2010, 12, 10380], we find that the theoretical ice nucleation rates are within 3 orders of magnitude of the measured rates over an ∼15 K temperature range. PMID:23763363

  5. Asymmetric Modeling of the Industrial Heavy Water Plant (PIAP)

    International Nuclear Information System (INIS)

    Software of asymmetric stationary simulation for the Industrial Heavy Water Plant (PIAP) was developed, based on an existing symmetric simulator (Brigitte 2.0).This software allows to turn off some of the isotopic enrichment twin units present in the plant and to simulate them asymmetrically, in other words, with different selection of parameters between twins.Other incorporations were done, such as passing flows between units and entering flows in strategic points of the plant.The iterative system in which the symmetric simulator is based was insufficient to develop the asymmetric simulator, so the system was modeled according to an implicit scheme for the units that form the simulator.This type of resolution resulted in a simulator that supports a big range of boundary conditions and internal parameters.Moreover, the time of calculus is short (∼3 minutes), making it actually useful.The asymmetric simulator is at the PIAP now, for its study and validation. It shows expected tendencies and results according to the symmetric simulator already validated

  6. Studying of Phenomenon of Biological Adaptation to Heavy Water

    Directory of Open Access Journals (Sweden)

    Oleg Mosin

    2014-12-01

    Full Text Available Biological influence of deuterium on cells of various taxonomic groups of prokaryotic and eucaryotic microorganisms realizing methylotrophic, chemoheterotrophic, photo-organotrophic, and photosynthetic ways of assimilation of carbon substrates (methylotrophic bacteria Brevibacterium methylicum, chemoheterotrophic bacteria Bacillus subtilis, photo-organotrophic halobacteria Halobacterium halobium, and green micro algae Chlorella vulgaris was investigated at the growth on media with heavy water (2H2O. For investigated microorganisms are submitted the data on growth and adaptation on the growth media containing as sources of deuterated substrates 2H2O, [2H]methanol and hydrolisates of deutero-biomass of methylotrophic bacteria B. methylicum, obtained after multistage adaptation to 2H2O. The qualitative and quantitative composition of intra- and endocellular amino acids, proteins, carbohydrates and fatty acids in conditions of adaptation to 2H2O is investigated. It is shown, that the effects observed at adaptation to 2H2O, possess a complex multifactorial character and connected to cytological, morphological and physiological changes – the magnitude of the lag- period, time of cellular generation, output of biomass, a parity ratio of synthesized amino acids, proteins, carbohydrates and lipids, and also with an evolutionary level of the organization of the investigated object and the pathways of assimilation of carbon substrates as well.

  7. Effective management of water systems in a chemical industry: a case study at Heavy Water Plant, Manuguru

    International Nuclear Information System (INIS)

    This paper describes about the important methods of water management in general followed by a description of the water system and measures taken/to be implemented at Heavy Water Plant, Manuguru in particular in order to effectively tackle the effluent water by reuse of the treated effluents

  8. An advanced nuclear power plant for heavy oil exploitation in the Venezuelan Orinoco oil belt

    International Nuclear Information System (INIS)

    The most important characteristics of the Orinoco Oil Belt (OOB) and of its heavy oil content, together with the main requirements for its exploitation, are presented here for analyzing the possibilities of the application of advanced nuclear power as main energy source in the heavy oil exploitation in the OOB. A steamsupply advanced nuclear cogeneration plant based on high temperature reactors is suggested for both the extraction and upgrading of the crude oil. The model consists of a plant for a 100 km2 oil field producing 100.000 barrels per day of refinery ready synthetic oil during 25 years. Three 1200 MW(th) reactors, built successively, supply a great portion of the required process heat, injection steam and electricity. Steam conditions are: for the process heat, a maximum pressure of 10 MPa at a temperature of 500deg C, and, for the injection steam, pressures between 12 and 17 MPa at saturation temperatures. Clear advantages for an advanced nuclear option application in the OOB development are substantiated, and a feasibility study is recommended. (orig.)

  9. Silica coated magnetite nanoparticles for removal of heavy metal ions from polluted waters

    CERN Document Server

    Dash, Monika

    2013-01-01

    Magnetic removal of Hg2+ and other heavy metal ions like Cd2+, Pb2+ etc. using silica coated magnetite particles from polluted waters is a current topic of active research to provide efficient water recycling and long term high quality water. The technique used to study the bonding characteristics of such kind of nanoparticles with the heavy metal ions is a very sensitive hyperfine specroscopy technique called the perturbed angular correlation technique (PAC).

  10. Investigation of the heavy water distillation system at the RA reactor

    International Nuclear Information System (INIS)

    The heavy water distillation system was tested because this was not done before the reactor start-up. Detailed inspection of the system components showed satisfactory results. Leak testing was done as well as the testing of the instrumentation which enables reliable performance of the system. Performance testing was done with ordinary water and later 2700 l of heavy water from the reactor was purified, decreasing the activity by 45%

  11. Pollution Status of Pakistan: A Retrospective Review on Heavy Metal Contamination of Water, Soil, and Vegetables

    OpenAIRE

    Amir Waseem; Jahanzaib Arshad; Farhat Iqbal; Ashif Sajjad; Zahid Mehmood; Ghulam Murtaza

    2014-01-01

    Trace heavy metals, such as arsenic, cadmium, lead, chromium, nickel, and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. In addition to these metals, copper, manganese, iron, and zinc are also important trace micronutrients. The presence of trace heavy metals in the atmosphere, soil, and water can cause serious problems to all organisms, and the ubiquitous bioavailability of these heavy metal can result in bioaccumulation in the food c...

  12. Advanced Electric Systems and Aerodynamics for Efficiency Improvements in Heavy Duty Trucks

    Energy Technology Data Exchange (ETDEWEB)

    Larry Slone; Jeffrey Birkel

    2007-10-31

    The Advanced Electric Systems and Aerodynamics for Efficiency Improvements in Heavy Duty Trucks program (DE-FC26-04NT42189), commonly referred to as the AES program, focused on areas that will primarily benefit fuel economy and improve heat rejection while driving over the road. The AES program objectives were to: (1) Analyze, design, build, and test a cooling system that provided a minimum of 10 percent greater heat rejection in the same frontal area with no increase in parasitic fan load. (2) Realize fuel savings with advanced power management and acceleration assist by utilizing an integrated starter/generator (ISG) and energy storage devices. (3) Quantify the effect of aerodynamic drag due to the frontal shape mandated by the area required for the cooling system. The program effort consisted of modeling and designing components for optimum fuel efficiency, completing fabrication of necessary components, integrating these components into the chassis test bed, completing controls programming, and performance testing the system both on a chassis dynamometer and on the road. Emission control measures for heavy-duty engines have resulted in increased engine heat loads, thus introducing added parasitic engine cooling loads. Truck electrification, in the form of thermal management, offers technological solutions to mitigate or even neutralize the effects of this trend. Thermal control offers opportunities to avoid increases in cooling system frontal area and forestall reduced fuel economy brought about by additional aerodynamic vehicle drag. This project explored such thermal concepts by installing a 2007 engine that is compliant with current regulations and bears additional heat rejection associated with meeting these regulations. This newer engine replaced the 2002 engine from a previous project that generated less heat rejection. Advanced power management, utilizing a continuously optimized and controlled power flow between electric components, can offer additional

  13. Heavy metal ions adsorption from mine waters by sawdust

    Directory of Open Access Journals (Sweden)

    G. Bogdanović

    2009-10-01

    Full Text Available In this work the results on the batch and column adsorption of copper and some associated ions by employing linden and poplar sawdust as a low-cost adsorbent are presented. The mine water from a local abandoned copper mine, as well as synthetic solutions of those ions which are the main constituents of the mine water were both used as a model-system in this study. The adsorption ability of the chosen sawdust to adsorb heavy metal ions is considered as a function of the initial pH of the solution and kind of metal ions. At lower pH of solutions the adsorption percentage (AD % decreases leading to a zero AD % at pH < 1.1. Maximum AD % is achieved at 3.5 < pH < 5. It was found that poplar and linden sawdust have both almost equal adsorption capacities against copper ions. The highest AD % ( ≈80% was achieved for Cu2+, while for Fe2+ it was slightly above 10%. The other considered ions (Zn2+ and Mn2+ were within this interval. The results obtained in the batch mode were verified through the column test by using the real mine water originating from an acid mine drainage (AMD of the copper mine „Cerovo“, RTB Bor. The breakthrough curves are presented as a function of the aqueous phase volume passed through the column allowing having an insight into the column adsorption features. Breakthrough points were determined for copper, manganese and zinc ions. A very high adsorption degree – higher than 99% was achieved in these experiments for all mentioned ions. After completing the adsorption, instead of desorption, the loaded sawdust was drained, dried and burned; the copper bearing ash was then leached with a controlled volume of sulphuric acid solution to concentrate copper therein. The obtained leach solution had the concentration of copper higher than 15 g dm-3 and the amount of H2SO4 high enough to serve as a supporting electrolyte suitable to be treated by the electrowinning for recovery of copper. The technology process based on the column

  14. Achieving safety through the design process for the heavy water new product reactor

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE) is presently completing the Conceptual Design Phase (CDP) for a heavy water new production reactor (NPR). In undertaking the development of requirements for the heavy water NPR, the DOE defined as a principal requirement that the reactor would be designed such that it would meet or exceed the level of safety and safety assurance achieved by modern commercial nuclear power plants. This paper discusses the strategy and methodology of implementing the line responsibilities for achieving safety in the design of the heavy water NPR

  15. A Management Strategy for the Heavy Water Reflector Cooling System of HANARO Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jung, H. S.; Park, Y. C.; Lim, S. P. (and others)

    2007-11-15

    Heavy water is used as the reflector and the moderator of the HANARO research reactor. After over 10 years operation since first criticality in 1995 there arose some operational issues related with the tritium. A task force team(TFT) has been operated for 1 year since September 2006 to study and deduce resolutions of the issues concerning the tritium and the degradation of heavy water in the HANARO reflector system. The TFT drew many recommendations on the hardware upgrade, tritium containing air control, heavy water quality management, waste management, and tritium measurement system upgrade.

  16. Features in ammonia plant for maximising heavy water production (Paper No. 2.10)

    International Nuclear Information System (INIS)

    Whenever an ammonia plant is linked with heavy water production, a system should be foreseen in the design stage itself for total conservation of D2 in synthesis gas and zero D2 loss. The process should ensure recycle of D2 rich condensate within the front end. This alone would be the single most important factor for improving heavy water production rate. The synthesis loop pressure should be chosen keeping in view the interest of heavy water plant (HWP). With vast experience in engineering NH3 and HWP plants, it is possible to integrate HWP requirements at the design stage itself. (author)

  17. Reconcentration technology of heavy water used as moderator and coolant at Cernavoda Plant

    International Nuclear Information System (INIS)

    One of the basic conditions to ensure the efficient operation of the CANDU reactor plant is maintaining a high isotope purity of heavy water in the moderator and cooling system. It is thus necessary that concentration be 99,80% mol. D2 O for the the moderator, and 99,75% mol. D2 O for the coolant, with water making up the rest. When the nuclear power plant is in service, heavy water in the moderator and cooling circuits may via various ways become mixed with H2 O impurities. Therefore, an isotope purification and, reconcentration of these fluids is necessary. A heavy-water reconcentration technology involving isotope distillation in vacuum in columns filled with phosphorous bronze, was developed by the Institute of Cryogenics and Isotope Separation Rm. Valcea, based on research and experience regarding heavy water concentration in the distillation pilot

  18. Containment for Heavy-Water Gas-Cooled Reactors

    International Nuclear Information System (INIS)

    The safety principles applicable to heavy-water, gas-cooled reactors are outlined, with a view to establishing containment specifications adapted to the sites available in Switzerland for the construction of nuclear plants. These specifications are derived from dose rates considered acceptable, in the event of a serious reactor accident, for persons living near the plant, and are based on-meteorological and demographic conditions representative of the majority of the country's sites. The authors consider various designs for the containment shell, taking into account the conditions which would exist in the shell after the maximum credible accident. The following types of shell are studied: pre-stressed concrete; pre-stressed concrete with steel dome; pre-stressed concrete with inner, leakproof steel lining; steel with concrete side shield to protect against radiation; double shell. The degree of leak proofing of the shells studied is regarded as a feature of the particular design and not as a fixed constructional specification. The authors assess the leak proofing properties of each type of shell and establish building costs for each of them on the basis of precise plans, with the collaboration of various specialized firms. They estimate the effectiveness of the various shells from a safety standpoint, in relation to different emergency procedures, in particular release into the atmosphere through appropriate filters and decontamination of the air within the shell by recycling through batteries of filters. The paper contains a very detailed comparison of about 10 cases corresponding to various combinations of design and emergency procedure; the comparison was made using a computer programme specially established for the purpose. The results are compared with those for a reactor of the same type and power, but assembled together with the heat exchangers in a pre-stressed concrete shell. (author)

  19. A Better Method for Evaluating Heavy Metal Water Pollution

    OpenAIRE

    Hering, Janet

    2002-01-01

    High concentrations of heavy metals, and even trace amounts of some, can be harmful to both plants and animals. The toxicity of heavy metal contamination, however, is highly dependent on the chemical form of the metal in question. Metals that are bound in particles or to organic (carbon-containing) compounds are less toxic than dissolved free ions, less toxic meaning that the metals are less readily available for uptake by marine organisms.

  20. "Periodic-table-style" paper device for monitoring heavy metals in water.

    Science.gov (United States)

    Li, Miaosi; Cao, Rong; Nilghaz, Azadeh; Guan, Liyun; Zhang, Xiwang; Shen, Wei

    2015-03-01

    If a paper-based analytical device (μ-PAD) could be made by printing indicators for detection of heavy metals in chemical symbols of the metals in a style of the periodic table of elements, it could be possible for such μ-PAD to report the presence and the safety level of heavy metal ions in water simultaneously and by text message. This device would be able to provide easy solutions to field-based monitoring of heavy metals in industrial wastewater discharges and in irrigating and drinking water. Text-reporting could promptly inform even nonprofessional users of the water quality. This work presents a proof of concept study of this idea. Cu(II), Ni(II), and Cr(VI) were chosen to demonstrate the feasibility, specificity, and reliability of paper-based text-reporting devices for monitoring heavy metals in water. PMID:25645265

  1. A Review of Laboratory-Scale Research on Upgrading Heavy Oil in Supercritical Water

    Directory of Open Access Journals (Sweden)

    Ning Li

    2015-08-01

    Full Text Available With the growing demand for energy and the depletion of conventional crude oil, heavy oil in huge reserve has attracted extensive attention. However, heavy oil cannot be directly refined by existing processes unless they are upgraded due to its complex composition and high concentration of heteroatoms (N, S, Ni, V, etc.. Of the variety of techniques for heavy oil upgrading, supercritical water (SCW is gaining popularity because of its excellent ability to convert heavy oil into valued, clean light oil by the suppression of coke formation and the removal of heteroatoms. Based on the current status of this research around the world, heavy oil upgrading in SCW is summarized from three aspects: Transformation of hydrocarbons, suppression of coke, and removal of heteroatoms. In this work, the challenge and future development of the orientation of upgrading heavy oil in SCW are pointed out.

  2. Advanced feed water distributing system for WWER 440 steam generators

    Energy Technology Data Exchange (ETDEWEB)

    Matal, O.; Klinga, J. [Energovyzkum Ltd, Brno (Switzerland); Grazl, K. [Vitkovice s.c., Ostrava (Switzerland); Tischler, J.; Mihalik, M. [SEP Atomove Elektrarne Bohunice (Slovakia)

    1995-12-31

    The original designed feed water distributing system was replaced by an advanced one. The characteristics of both feed water distributing systems have been measured and evaluated. The paper deals with the problems of measurement and evaluation of both feed water distributing system characteristics and comparison of statistical data obtained. (orig.). 3 refs.

  3. Comparative study of electrical breakdown properties of deionized water and heavy water under pulsed power conditions

    Science.gov (United States)

    Veda Prakash, G.; Kumar, R.; Saurabh, K.; Nasir, Anitha, V. P.; Chowdhuri, M. B.; Shyam, A.

    2016-01-01

    A comparative study of electrical breakdown properties of deionized water (H2O) and heavy water (D2O) is presented with two different electrode materials (stainless steel (SS) and brass) and polarity (positive and negative) combinations. The pulsed (˜a few tens of nanoseconds) discharges are conducted by applying high voltage (˜a few hundred kV) pulse between two hemisphere electrodes of the same material, spaced 3 mm apart, at room temperature (˜26-28 °C) with the help of Tesla based pulse generator. It is observed that breakdown occurred in heavy water at lesser voltage and in short duration compared to deionized water irrespective of the electrode material and applied voltage polarity chosen. SS electrodes are seen to perform better in terms of the voltage withstanding capacity of the liquid dielectric as compared to brass electrodes. Further, discharges with negative polarity are found to give slightly enhanced discharge breakdown voltage when compared with those with positive polarity. The observations corroborate well with conductivity measurements carried out on original and post-treated liquid samples. An interpretation of the observations is attempted using Fourier transform infrared measurements on original and post-treated liquids as well as in situ emission spectra studies. A yet another important observation from the emission spectra has been that even short (nanosecond) duration discharges result in the formation of a considerable amount of ions injected into the liquid from the electrodes in a similar manner as reported for long (microseconds) discharges. The experimental observations show that deionised water is better suited for high voltage applications and also offer a comparison of the discharge behaviour with different electrodes and polarities.

  4. Comparative study of electrical breakdown properties of deionized water and heavy water under pulsed power conditions

    International Nuclear Information System (INIS)

    A comparative study of electrical breakdown properties of deionized water (H2O) and heavy water (D2O) is presented with two different electrode materials (stainless steel (SS) and brass) and polarity (positive and negative) combinations. The pulsed (∼a few tens of nanoseconds) discharges are conducted by applying high voltage (∼a few hundred kV) pulse between two hemisphere electrodes of the same material, spaced 3 mm apart, at room temperature (∼26-28 °C) with the help of Tesla based pulse generator. It is observed that breakdown occurred in heavy water at lesser voltage and in short duration compared to deionized water irrespective of the electrode material and applied voltage polarity chosen. SS electrodes are seen to perform better in terms of the voltage withstanding capacity of the liquid dielectric as compared to brass electrodes. Further, discharges with negative polarity are found to give slightly enhanced discharge breakdown voltage when compared with those with positive polarity. The observations corroborate well with conductivity measurements carried out on original and post-treated liquid samples. An interpretation of the observations is attempted using Fourier transform infrared measurements on original and post-treated liquids as well as in situ emission spectra studies. A yet another important observation from the emission spectra has been that even short (nanosecond) duration discharges result in the formation of a considerable amount of ions injected into the liquid from the electrodes in a similar manner as reported for long (microseconds) discharges. The experimental observations show that deionised water is better suited for high voltage applications and also offer a comparison of the discharge behaviour with different electrodes and polarities

  5. Comparative study of electrical breakdown properties of deionized water and heavy water under pulsed power conditions

    Energy Technology Data Exchange (ETDEWEB)

    Veda Prakash, G.; Kumar, R.; Saurabh, K.; Nasir,; Anitha, V. P.; Chowdhuri, M. B.; Shyam, A. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2016-01-15

    A comparative study of electrical breakdown properties of deionized water (H{sub 2}O) and heavy water (D{sub 2}O) is presented with two different electrode materials (stainless steel (SS) and brass) and polarity (positive and negative) combinations. The pulsed (∼a few tens of nanoseconds) discharges are conducted by applying high voltage (∼a few hundred kV) pulse between two hemisphere electrodes of the same material, spaced 3 mm apart, at room temperature (∼26-28 °C) with the help of Tesla based pulse generator. It is observed that breakdown occurred in heavy water at lesser voltage and in short duration compared to deionized water irrespective of the electrode material and applied voltage polarity chosen. SS electrodes are seen to perform better in terms of the voltage withstanding capacity of the liquid dielectric as compared to brass electrodes. Further, discharges with negative polarity are found to give slightly enhanced discharge breakdown voltage when compared with those with positive polarity. The observations corroborate well with conductivity measurements carried out on original and post-treated liquid samples. An interpretation of the observations is attempted using Fourier transform infrared measurements on original and post-treated liquids as well as in situ emission spectra studies. A yet another important observation from the emission spectra has been that even short (nanosecond) duration discharges result in the formation of a considerable amount of ions injected into the liquid from the electrodes in a similar manner as reported for long (microseconds) discharges. The experimental observations show that deionised water is better suited for high voltage applications and also offer a comparison of the discharge behaviour with different electrodes and polarities.

  6. Decontamination of waste waters and soils from heavy metals using artificial aluminosilicate sorbents

    International Nuclear Information System (INIS)

    The physico-chemical properties of the commercial artificial aluminosilicate sorbent 'beringite' and a newly prepared sorbents (named 'S') were tested in order to test compare usefulness for decontamination of waste waters from heavy metals. Beringite and lime doses were applied to contaminated soils and their effects on plants growth and heavy metals uptake were estimated. The test showed a possible better usefulness of 'S' sorbents for waste water treatment. On the soils studied no differences between beringite and lime application were detected

  7. A Review of Heavy Metals in Water, Sediment and Living Organisms in the Black Sea;

    OpenAIRE

    Boran, Muhammet; Altınok, Ilhan

    2010-01-01

    Black Sea waters remain heavily impacted by a number of pollutants originating from different sources such as direct and indirect discharge of land based pollutants, sewage etc. The Black Sea environment is highly contaminated in many urban and industrialized areas of the many countries, resulting in severe ecotoxicological impacts. Heavy metals are toxic substances that accumulate in food chains with the increasing concentrations. In this review, heavy metal pollution in water column and ...

  8. A study on the establishment of component/equipment performance criteria considering Heavy Water Reactor characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Keun Sun; Kwon, Young Chul; Lee, Min Kyu; Lee, Yun Soo [Sunmoon Univ., Asan (Korea, Republic of); Chang, Seong Hoong; Ryo, Chang Hyun [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Kim, Soong Pyung; Hwnag, Jung Rye; Chung, Chul Kee [Chosun Univ., Gwangju (Korea, Republic of)

    2002-03-15

    Foreign and domestic technology trends, regulatory requirements, design and researches for heavy water reactors are analyzed. Safety design guides of Canada industry and regulatory documents and consultative documents of Canada regulatory agency are reviewed. Applicability of MOST guidance 16 Revision 'guidance for technical criteria of nuclear reactor facility' is reviewed. Specific performance criteria are established for components and facilities for heavy water reactor.

  9. Adsorption Mechanisms of Heavy Metal Ions from Drinking Water by Weakly Basic Anion Exchange Resins

    Institute of Scientific and Technical Information of China (English)

    赵璇; 何仕均; 杨磊

    2002-01-01

    Heavy metal micro-contaminants can be removed from water sources technologies. Weakly basic anion exchange resins offer the best ability to remove trace amounts of heavy metals with high selectivity. This paper discusses how weakly basic resins adsorb heavy metals using two different approaches. The removal of mercury, cadmium, and lead ions is based on the fundamental theory of coordination chemistry. The mechanism is not ion exchange but extractive adsorption of heavy metal salts. However, the marked preferential adsorption of chromate by weakly basic anion exchange can be explained using the traditional theory of ion exchange. A lab-scale study produced positive results for the removal of trace amounts of heavy metal ions from drinking water.

  10. Bioaccumulation of heavy metals in organs of fresh water fish Cyprinus carpio (Common carp)

    International Nuclear Information System (INIS)

    The objective of the present study is to determine the bioaccumulation of heavy metals in various organs of the fresh water fish exposed to heavy metal contaminated water system. The experimental fish was exposed to Cr. Ni, Cd and Pb at sublethal concentrations for periods of 32 days. The elements Cd, Pb, Ni and Cr were assayed using Shimadzu AA 6200 atomic absorption spectrophotometry and the results were given as μg/g dry wt. The accumulation of heavy metal gradually increases in liver during the heavy metal exposure period. All the results were statistically significant at p Pb > Ni > Cr and Pb > Cd > Ni > Cr. Similarly, in case of kidney and flesh tissues, the order was Pb > Cd > Cr > Ni and Pb > Cr > Cd > Ni. In all heavy metals, the bioaccumulation of lead and cadmium proportion was significantly increased in the tissues of Cyprinus carpio (Common carp)

  11. Accumulation of heavy metals in water, sediments and wetland plants of kizilirmak delta (samsun, Turkey).

    Science.gov (United States)

    Engin, M S; Uyanik, A; Kutbay, H G

    2015-01-01

    In this study, concentrations of heavy metals (Fe, Mn, Ni, Co, Zn, Cu, and Pb) were measured in water bodies including streams, bottom sediments and various wetland plants of Kızılırmak Delta. Kızılırmak Delta is one of the largest and the most important natural wetlands in Turkey and has been protected by Ramsar convention since 1993. The heavy metal concentrations in water were found lower than that of national standards for protected lakes and reserves. In bottom sediments and wetland plants, however, the accumulated amounts of different heavy metals varied in the following order: Fe>Mn>Zn>Ni>Co>Cu>Pb, and Fe>Mn>Zn>Ni>Co respectively. Heavy metal uptake of Hydrocharis morsus-ranae and Myriophyllum verticillatum plants among others were found far above the toxic levels and they might be used as bio-indicators and heavy metal accumulators in polluted natural areas. PMID:25174426

  12. Technology breakthrough by Heavy Water Board in material support to Indian nuclear power programme

    International Nuclear Information System (INIS)

    Heavy Water Board (HWB) is the sole agency in the country for production and sustained supply of heavy water, nuclear grade solvents and enriched elemental boron which are the key input material for Indian Nuclear Power Programme. DAE has ventured to develop heavy water technology indigenously starting from scratch. H2S-H2O bi-thermal process was developed starting from laboratory studies to pilot plant and breakthrough was achieved by setting up first industrial plant at Kota and double capacity plant at Manuguru. In early 1960's, NH3-H2 mono-thermal process was at nascent stage of development. The rich experience from first industrial plant set up at Baroda has led to success story in second generation plants at Thal and Hazira, totally with indigenous efforts. NH3-H2O front-end process had also been developed for ammonia based Heavy Water Plants (HWPs) making them independent of fertilizer plants. Performance indicators of operating HWPs have reached the zenith level. India is the largest global producer of heavy water and is the only country using multiple technologies. HWB is also fulfilling the global demand of high quality heavy water. HWB has diversified into other activities like industrial production of other nuclear materials and development of spin off technologies. (author)

  13. 1000 tones of heavy water produced at ROMAG PROD, Drobeta-Turnu Severin

    International Nuclear Information System (INIS)

    On May 25, 2001 the heavy water plant ROMAG PROD at Drobeta-Turnu Severin recorded the production of the 1000-th tone of nuclear purity heavy water. The heavy water plant ROMAG PROD makes use of a technology based on the results of isotopic deuterium separation research carried out at the Research and Design Institutes of Cluj, Craiova, Pitesti and Ploiesti during 1957-1970 and the separation technology tested at Ramnicu-Valcea pilot plant (at present the Cryogenics and Isotope Separation Institute). The first investments at ROMAG PROD were made in 1979 and on July 17, 1988 was produced the first amount of heavy water at the required parameters for CANDU type nuclear reactors. The period between 1990-1992 was dedicated to the project completion, upgrading the technological facilities and retrofitting the environmental protection and monitoring systems. Production was resumed in 1992. The first 500 t of heavy water required for the Cernavoda NPP first reactor operation were produced by summer 1997. The additional amount of 500 t of heavy water was produced between 1997-2001. ROMAG PROD obtained the ISO 9001/2001 certificate for the quality management system, the ISO 14001/1997 certificate for the environmental management system and the new environmental permit

  14. The projects for heavy water production of the Argentine National Atomic Energy Commission

    International Nuclear Information System (INIS)

    The bases and scope of the projects for heavy water production that are being currently developed by the Argentine National Atomic Energy Commission (CNEA) are described. As an introduction, the following points are presented: a) the fundamentals of heavy water utilization in a nuclear reactor, with a mention of its properties and uses, b) a review of the physicochemical bases of the principal methods for heavy water production: chemical exchange (monothermal and bithermal processes), distillation and electrolysis, with tables summarizing the fundamental characteristics of the first two ones, and an evaluation of the different production methods from the viewpoint of their application in an industrial scale; and c) a synthetic information, in the form of tables, about the world's heavy water production. The subject of heavy water production in Argentina is treated in the principal section, describing the scope, location, main characteristics and chemical processes corresponding to the projects being developed by CNEA, which currently are the installation of an Industrial Plant in Arroyito (Province of Neuquen), purchased on a turnkey basis and using the NH3/H2 isotopic exchange method; the installation of an Experimental Plant in Atucha (Province of Buenos Aires), for the development of the domestic technology of heavy-water production by the SH2/H2O isotopic exchange method, and the development of the engineering of an industrial plant (''Module 80''), based on the Experimental Plant's technology. (M.E.L.)

  15. Black water sludge reuse in agriculture: are heavy metals a problem?

    Science.gov (United States)

    Tervahauta, Taina; Rani, Sonia; Hernández Leal, Lucía; Buisman, Cees J N; Zeeman, Grietje

    2014-06-15

    Heavy metal content of sewage sludge is currently the most significant factor limiting its reuse in agriculture within the European Union. In the Netherlands most of the produced sewage sludge is incinerated, mineralizing the organic carbon into the atmosphere rather than returning it back to the soil. Source-separation of black water (toilet water) excludes external heavy metal inputs, such as industrial effluents and surface run-offs, producing sludge with reduced heavy metal content that is a more favorable source for resource recovery. The results presented in this paper show that feces is the main contributor to the heavy metal loading of vacuum collected black water (52-84%), while in sewage the contribution of feces is less than 10%. To distinguish black water from sewage in the sludge reuse regulation, a control parameter should be implemented, such as the Hg and Pb content that is significantly higher in sewage sludge compared to black water sludge (from 50- to 200-fold). The heavy metals in feces and urine are primarily from dietary sources, and promotion of the soil application of black water sludge over livestock manure and artificial fertilizers could further reduce the heavy metal content in the soil/food cycle. PMID:24794814

  16. Heavy water reactor user requirement document status and path forward

    International Nuclear Information System (INIS)

    This is a Power Point presentation containing: -1. Outline; - 2. Background - Stages and the HWR-URD; - 3. Background - What do we have now?; - 4. Draft 'D0' of the HWR-URD; - 5. The 2001 April Consultancy; - 6. The Path Forward. - 7. Summary. The 2001 April consultancy addressed the following items: - 1. Status of the URD: - The document structure is substantially complete. Appendices or paragraphs need to be added on some topics; - The URD covers the overall requirements for the design of the nuclear island (NI) and interfaces to the BOP for future HWRs. It contains policies, high-level requirements and important requirements for key areas that are of interest to HWR users; - The draft focuses on horizontal-pressure-tube, heavy water moderated and cooled HWRs. When and if other types need to be considered, the TWG will identify these and direct how they are to be addressed; - The level of detail in the draft and its treatment of the international aspects of the topic are appropriate; - 2. Areas needing further consideration: - While intended for future reactors, it is recognized that regulators may wish to use the URD as a benchmark for evaluating existing or replicate reactors; - The international aspects of the URD require detailed review at each stage of its development; - The EUR and EPRI-URD have had targeted reviews by the regulators. This may be appropriate for the HWR-URD but would add 6 to 12 months to the schedule; - These items will be the focus of the AGM planned for 2002 January. The Path Forward section pinpoints the terms: - 2001 August, implying the task, incorporate comments from April Consultancy, producing draft D1; - 2002 January, implying AGM in Vienna, namely, focus on areas needing further consideration: - Ensure requirements are clearly differentiated from desirable features; - Confirm international aspects are appropriately considered; - Establish need for additional step - regulatory review; - 2002, implying revise URD to reflect

  17. Neutronic study of a light water core reflected with heavy water

    International Nuclear Information System (INIS)

    For the design of the high flux reactor with extracted beams, we have performed an experimental study on a light water and highly enriched uranium core surrounded by a thick heavy water reflector. This study was made with a critical facility specially designed. The scope of the measurements was double: i) to check the calculation methods then available ii) to evaluate effects not easily calculated owing to the reactor geometry. The main experiments were the following - criticality measurements for various core geometries - measurement of void and temperature coefficients - distribution of neutron density and fission sources - study of kinetic parameters and calibration of control elements - measurements of spectral indices and of flux perturbations due to the presence in the reflector of channels for the neutron beam extraction. The primary analysis of the experimental results gives generally a satisfactory agreement with calculations and shows that in some cases better hypotheses should be taken. (authors)

  18. Advanced water treatment as a tool in water scarcity management

    DEFF Research Database (Denmark)

    Harremoes, Poul

    2000-01-01

    of water. In the former case, the water is lost by evaporation and polluted. In the latter case, the water is not lost but heavily polluted. With increasing scarcity, the value of water and the need for controls increase. In this situation, water reuse becomes an option that has been considered exotic......The water resource is under increasing pressure, both from the increase in population and from the wish to improve the living standards of the individual. Water scarcity is defined as the situation where demand is greater than the resource. Water scarcity has two distinctly different dimensions......: water availability and water applicability. The availability is a question of quantitative demand relative to resource. The applicability is a question of quality suitability for the intended use of the water. There is a significant difference in this regard with respect to rural versus urban use...

  19. The influence of Water Hyacinth to Decrease the Heavy Metals Mercury (Hg Concentration for Irrigation

    Directory of Open Access Journals (Sweden)

    Rusnam Rusnam

    2013-01-01

    Full Text Available Research was conducted in July – September 2012, mercury analysis performed in Environmental Engineering of Engineering Faculty, Andalas University. Levels of mercury that are permitted by Government Regulation Republic Indonesia No. 82 of 2001, fourth grade for water quality is 0.005 mg/l. There mercury content of 0.020169 mg/l in irrigated areas Batang Hari. The research aims to find out ability level water hyacinth (Eichornia crassipes Sloms to decrease content mercury and to find water depth suitable for phytoremediation. This research uses experimental methods in laboratory. Initial content of heavy metals mercury (Hg that has been used is 0.02 mg/l in depth water 40 cm and 50 cm. Result in decreased concentrations of heavy metals mercury compared with quality standard heavy metal mercury for fourth grade water quality. The result showed that water hyacinth was able to restore the water quality of heavy metal contaminated Hg for irrigation. Decrease in the concentration of heavy metals mercury of 20 days at depth 40 cm reaching 94.3 % and depth of 50 cm reaching 85.7 %. Mercury concentration reaches a threshold quality standard for irrigation water depth of 40 cm during the 12 days and depth of 50 cm during 16 days.

  20. Hydrothermally modified fly ash for heavy metals and dyes removal in advanced wastewater treatment

    Energy Technology Data Exchange (ETDEWEB)

    Visa, Maria, E-mail: maria.visa@unitbv.ro; Chelaru, Andreea-Maria, E-mail: andreea.chelaru1@yahoo.com

    2014-06-01

    Fly ash resulted from coal burning is a waste that can be used in wastewater treatment for removal of dyes and heavy metals by adsorption. Class “F” fly ash (FA), collected from the Central Heat and Power (CHP) Plant Brasov (Romania), with oxides composition SiO{sub 2}/Al{sub 2}O{sub 3} over 2.4 was used for obtaining a new substrate with good adsorption capacity for dyes and heavy metals from wastewater. A new material was obtained from modified fly ash with NaOH and hexadecyltrimethylammonium bromide (HTAB) a cationic surfactant. Contact time, optimum amount of substrate and the pH corresponding to 50 mL solution of pollutants were the parameters optimized for obtaining the maximum efficiency in the adsorption process. The optimized adsorption parameters were further used in thermodynamic and kinetic studies of the adsorption processes. The adsorption kinetic mechanisms, and the substrate capacities are further discussed correlated with the surface structure (XRD), composition (EDS, FTIR), and morphology (SEM, AFM). The results indicate that the novel nano-substrate composite with fly ash modified can be used as an efficient and low cost adsorbent for simultaneous removal of dyes and heavy metals, the resulted water respects the discharge regulations.

  1. Hydrothermally modified fly ash for heavy metals and dyes removal in advanced wastewater treatment

    International Nuclear Information System (INIS)

    Fly ash resulted from coal burning is a waste that can be used in wastewater treatment for removal of dyes and heavy metals by adsorption. Class “F” fly ash (FA), collected from the Central Heat and Power (CHP) Plant Brasov (Romania), with oxides composition SiO2/Al2O3 over 2.4 was used for obtaining a new substrate with good adsorption capacity for dyes and heavy metals from wastewater. A new material was obtained from modified fly ash with NaOH and hexadecyltrimethylammonium bromide (HTAB) a cationic surfactant. Contact time, optimum amount of substrate and the pH corresponding to 50 mL solution of pollutants were the parameters optimized for obtaining the maximum efficiency in the adsorption process. The optimized adsorption parameters were further used in thermodynamic and kinetic studies of the adsorption processes. The adsorption kinetic mechanisms, and the substrate capacities are further discussed correlated with the surface structure (XRD), composition (EDS, FTIR), and morphology (SEM, AFM). The results indicate that the novel nano-substrate composite with fly ash modified can be used as an efficient and low cost adsorbent for simultaneous removal of dyes and heavy metals, the resulted water respects the discharge regulations.

  2. [Advance in the bioavailability monitoring of heavy metal based on microbial whole-cell sensor].

    Science.gov (United States)

    Hou, Qi-Hui; Ma, An-Shou; Zhuang, Xiu-Liang; Zhuang, Guo-Qiang

    2013-01-01

    Microbial whole-cell biosensor is an excellent tool to assess the bioavailability of heavy metal in soil and water. However, the traditional physicochemical instruments are applied to detect the total metal. Furthermore, microbial whole-cell biosensor is simple, rapid and economical in manipulating, and is thus a highly qualified candidate for emergency detection of pollution incidents. The biological component of microbial whole-cell biosensor mostly consists of metalloregulatory proteins and reporter genes. In detail, metalloregulatory proteins mainly include the MerR family, ArsR family and RS family, and reporter genes mainly include gfp, lux and luc. Metalloregulatory protein and reporter gene are related to the sensitivity, specificity and properties in monitoring. The bioavailability of heavy metals is alterable under different conditions, influenced by pH, chelate and detection methods and so on. Increasing the accumulation of intracellular heavy metal, modifying the metalloregulatory proteins and optimizing the detecting conditions are important for improving the sensitivity, specificity and accuracy of the microbial whole-cell biosensor. The future direction of microbial whole-cell biosensor is to realize the monitoring of pollutions in situ and on line. PMID:23487961

  3. Hydrothermally modified fly ash for heavy metals and dyes removal in advanced wastewater treatment

    Science.gov (United States)

    Visa, Maria; Chelaru, Andreea-Maria

    2014-06-01

    Fly ash resulted from coal burning is a waste that can be used in wastewater treatment for removal of dyes and heavy metals by adsorption. Class “F” fly ash (FA), collected from the Central Heat and Power (CHP) Plant Brasov (Romania), with oxides composition SiO2/Al2O3 over 2.4 was used for obtaining a new substrate with good adsorption capacity for dyes and heavy metals from wastewater. A new material was obtained from modified fly ash with NaOH and hexadecyltrimethylammonium bromide (HTAB) a cationic surfactant. Contact time, optimum amount of substrate and the pH corresponding to 50 mL solution of pollutants were the parameters optimized for obtaining the maximum efficiency in the adsorption process. The optimized adsorption parameters were further used in thermodynamic and kinetic studies of the adsorption processes. The adsorption kinetic mechanisms, and the substrate capacities are further discussed correlated with the surface structure (XRD), composition (EDS, FTIR), and morphology (SEM, AFM). The results indicate that the novel nano-substrate composite with fly ash modified can be used as an efficient and low cost adsorbent for simultaneous removal of dyes and heavy metals, the resulted water respects the discharge regulations.

  4. Selective Extraction of Heavy and Light Lanthanides from Aqueous Solution by Advanced Magnetic Nanosorbents.

    Science.gov (United States)

    Zhang, Huijin; McDowell, Rocklan G; Martin, Leigh R; Qiang, You

    2016-04-13

    Rare earth elements (REEs) make unique and vital contributions to our current world of technology. Separating and recycling REEs is of great importance to diversify the sources of REEs and advance the efficient use of REE resources when the supply is limited. In light of separation nanotechnology, diethylenetriamine-pentaacetic acid (DTPA) functionalized magnetic nanosorbents have been synthesized and investigated for the highly selective extraction of heavy (Sm-Ho) and light (La-Nd) lanthanides (Ln) from aqueous solutions. The results demonstrated that the separation factor (SF) between heavy-Ln and light-Ln groups reached the maximal value of 11.5 at low pH value of 2.0 in 30 min. For example, the SFs of Gd/La and Dy/La pairs were up to 10 times higher than that reported by other studies. Besides the excellent selectivity, our double-coated magnetic nanoparticles coupled with diethylenetriaminepentaacetic acid (dMNP-DTPA) nanosorbents are more advantageous in that the Ln(III) sorption was effectively and quickly (in 30 min) achieved in acid solutions with pH values as low as 2.0. Such attributes ensure a stronger adaptability to the harsh environments of REE recycling processes. Displacement phenomena were subsequently observed between the heavy-Ln and light-Ln ions that were coexisting in solution and competing for the same sorption sites, causing the increase in sorption capacity of heavy Ln on the surface of nanosorbents with time. The order of affinity of Ln(III) to DTPA-functionalized magnetic nanosorbents perfectly followed the corresponding stability constants between Ln(III) and nonimmobilized DTPA. Displacement phenomena and lanthanide contraction, as well as the surface nanostructures of DTPA-functionalized nanosorbents, significantly improved the separation factors of heavy-Ln/light-Ln pairs. The Ln(III) interaction with DTPA-functionalized magnetic nanosorbents followed the pseudo-second-order kinetics with a correlation coefficient extremely high and

  5. Advanced Methods for Treatment of Organic Compounds Contamined Water

    Directory of Open Access Journals (Sweden)

    PREDESCU Andra

    2009-08-01

    Full Text Available The progress recorded in the field of science and advanced engineering at nanometric scale supplies largeopportunities for more efficient (from the point of view of the costs and more ecological approach of the processes ofwater purifying. This paper delivers a short description of the possibilities of using advanced materials in purifying thecontamined water with toxic metallic ions, organic and anorganic compounds. The opportunities and challenges werealso emphasized when nanomaterials were used for the surface, underground and industrial used waters treatment.

  6. Investigation of Toxic Heavy Metals in Drinking Water of Agra City, India

    Directory of Open Access Journals (Sweden)

    P. Susan Verghese

    2015-09-01

    Full Text Available Water quality of Agra city is impaired by the presence of large number of industries in the city. From the observed data it is found that drinking water of Agra city is contaminated with toxic heavy metals like chromium, copper, cadmium, lead, and nickel. Among all these heavy metals, chromium is found to be in comparatively large amounts because most of the leather industries located in Agra city adopt chrome tanning procedure as their basic step for dehairing and dehiding. Presence of high concentration of chromium and other heavy metals in drinking water pose deleterious effects on the health of human beings therefore it becomes necessary to employ certain technological methods to keep the concentration of such toxic heavy metals within their desirable limits.

  7. Experience of excess heavy metal content in drinking water for human organizm

    Directory of Open Access Journals (Sweden)

    Г.І. Архіпова

    2010-01-01

    Full Text Available  Heavy metals are toxic to a widespread of pollutants. Heavy metals are widely used in various industrial enterprises, and, despite the penetrating clearing actions, compounds of heavy metals in industrial waste water. A considerable number of these compounds into the water through the atmosphere. The environmental risk of heavy metals is that they are actively absorbed by phytoplankton and then transferred to humans by food chain. Into two groups of metals, different in their ecological significance. The first group of elements, maximum allowable concentration (MAC are close to their background values in natural water. This, for example, iron, manganese, strontium. The second group includes metals (copper, lead, zinc, which far exceed the MCL real natural background values. For the normal functioning of the human body requires to achieve a balanced exchange of microelements, the violation of which leads to serious diseases and poisonings.

  8. Study of Advanced Oxidation System for Water Treatment

    International Nuclear Information System (INIS)

    Hygiene water is still a big problem globally as well as energy and food, especially in Indonesia where more than 70 % lived in Java island. One of the efforts in treating hygiene water is to recycle the used water. In this case it is needed clean water technology. Many methods have been done, this paper describes the advanced oxidation technology system based on ozone, titania and plasma discharge. (author)

  9. Studying of Phenomenon of Biological Adaptation to Heavy Water

    OpenAIRE

    Oleg Mosin; Ignat Ignatov; Dmitry Skladnev; Vitaly Shvets

    2014-01-01

    Biological influence of deuterium on cells of various taxonomic groups of prokaryotic and eucaryotic microorganisms realizing methylotrophic, chemoheterotrophic, photo-organotrophic, and photosynthetic ways of assimilation of carbon substrates (methylotrophic bacteria Brevibacterium methylicum, chemoheterotrophic bacteria Bacillus subtilis, photo-organotrophic halobacteria Halobacterium halobium, and green micro algae Chlorella vulgaris) was investigated at the growth on media with heavy wate...

  10. Halden Boiling Water Reactor. Plant Performance and Heavy-Water Management

    International Nuclear Information System (INIS)

    The Halden boiling heavy-water reactor, designed and built by the Norwegian Institutt for Atomenergi, has since June 1958 been operated as an international project. On its second charge the reactor was operated at power levels up to 25 MW and most of the time at a pressure of 28.5 kg/cm2. During the period from July 1964 to December 1966 the plant availability was close to 64% including shutdowns because of test fuel failures and loading/unloading of fuel. Disregarding such stops, the availability was close to 90%. The average burnup of the core is about 6200 MWd/t UO2 : the most highly exposed elements have reached 10000 MWd/t UO2. The transition temperature of the reactor tank has been followed closely. The results of the surveillance programme and the implication on the reactor operation are discussed. The reactor is located in a cave in a rock. Some experiences with such a containment are given. To locate failed test-fuel elements a fuel failure location system has been installed. A fission gas collection system has saved valuable reactor time during clean-up of the reactor system following test fuel failures. Apart from one incident with two of the control stations, the plant control and instrumentation systems have functioned satisfactorily. Two incidents with losses of 150 and 200 kg of heavy water have occurred. However, after improved methods for leakage detection had been developed, the losses have been kept better than 50 g/h . Since April 1962 the isotopic purity of the heavy water (14 t) has decreased from 99.75 to 99.62%. The tritium concentration is now slightly above 700 μC/cm3. This activity level has not created any serious operational or maintenance problems. An extensive series of water chemistry experiments has been performed to study the influence of various operating parameters on radiolytic gas formation. The main results of these experiments will be reported. Different materials such as mild steel, ferritic steel and aluminium have been

  11. Comparative study of plutonium burning in heavy and light water reactors

    International Nuclear Information System (INIS)

    There is interest in the U.S. and world-wide in reducing the burden on geological nuclear fuel disposal sites. In some disposal scenarios, the decay heat loading of the surrounding rock limits the commercial spent fuel capacity of the sites. In the long term (100 to 1,500 years), this decay heat is generated primarily by actinides, particularly 241Am and 241Pu. One possible approach to reducing this decay-heat burden would be to reprocess commercial spent nuclear fuel and use intermediate-tier thermal reactors to 'burn' these actinides and other transuranics (plutonium and higher actinides). The viability of this approach is dependent on the detailed changes in chemical and isotopic compositions of actinide-bearing fuels after irradiation in thermal reactor spectra. The intermediate-tier thermal burners could bridge the commercial water-cooled reactors and fast reactors required for ultimate consumption of the transuranics generated in the commercial reactors. This would reduce the number of such fast reactors required to complete the mission of burning transuranics. If thermal systems are to be used for the transmutation mission, it is likely that they would be similar to or are advanced versions of the systems currently used for power generation. In both the U.S. and Canada, light- and heavy-water-cooled thermal reactors are used for power generation in the commercial nuclear sector. About 103 pressurized- and boiling- light water reactors (PWRs and BRWs) are deployed in the U.S. nuclear industry while about 18 CANDU (heavy-water-cooled) reactors are used in the Canadian industry. There are substantial differences between light and heavy water-cooled reactors that might affect transmutation potential. These arise from differences in neutron balance of the reactors, in neutron energy spectra, in operational approaches (e.g., continuous refueling enhancing fuel burnup), and so on. A systematic study has been conducted to compare the transmutation potentials of

  12. DETERMINATION OF HEAVY METALS IN FISH, WATER AND SEDIMENTS OF AVSAR DAM LAKE IN TURKEY

    Directory of Open Access Journals (Sweden)

    M. Öztürk ، G. Özözen ، O. Minareci ، E. Minareci

    2009-04-01

    Full Text Available In the present study, some heavy metals (Cd, Cr, Cu, Fe, Ni and Pb were seasonally determined in water, sediment and some tissues of Cyprinus carpio from Avsar Dam Lake, which is an important water source for irrigation and drinking in Turkey. Heavy metal levels in water, sediment and fish samples were analyzed by inductively coupled plasma spectroscopy (ICP/AES. The obtained results showed that the average values of Fe in water samples were higher than the respective reference values for fresh water. Results for levels in water were compared with national and international water quality guidelines, as well as literature data reported for the lakes. The analysis of heavy metals in sediments indicated that among the six heavy metals tested, Fe was maximally accumulated, followed by Ni, Cu, Cr, Pb and Cd. Heavy metal concentrations were found to decrease in sequence of the Cyprinus carpio samples, in the muscle and stomach-intestine as Fe > Cu > Pb> Ni > Cr > Cd; in the gill, heart and liver as Fe > Cu > Ni > Pb > Cr > Cd and in the air sac as Fe > Cu > Ni > Pb > Cd >Cr. In the fish samples, cadmium, chromium, nickel and lead concentrations exceeded the tolerable values provided by international institutions.

  13. Advanced water treatment as a tool in water scarcity management

    DEFF Research Database (Denmark)

    Harremoes, Poul

    2000-01-01

    until recently. This paper sets the stage with respect to perspective and management options related to implementation of water reuse. Water treatment has to be interpreted as the means by which to purify the water from any degree of impurity to any degree of purity that fits the desired use, including......The water resource is under increasing pressure, both from the increase in population and from the wish to improve the living standards of the individual. Water scarcity is defined as the situation where demand is greater than the resource. Water scarcity has two distinctly different dimensions......: water availability and water applicability. The availability is a question of quantitative demand relative to resource. The applicability is a question of quality suitability for the intended use of the water. There is a significant difference in this regard with respect to rural versus urban use of...

  14. Heavy metal displacement in salt-water-irrigated soil during phytoremediation

    Energy Technology Data Exchange (ETDEWEB)

    Wahla, Intkhab Hazoor [Department of Agronomy, 2004 Throckmorton Plant Sciences Center, Kansas State University, Manhattan, Kansas 66506-5501 (United States); Kirkham, M.B. [Department of Agronomy, 2004 Throckmorton Plant Sciences Center, Kansas State University, Manhattan, Kansas 66506-5501 (United States)], E-mail: mbk@ksu.edu

    2008-09-15

    In regions where phytoremediation is carried out, brackish water must often be used. However, no information exists concerning the consequences of saline-water irrigation on the mobility of heavy metals in sludge applied to soil during phytoremediation. The purpose of this experiment was to determine the effect of NaCl irrigation on displacement of seven heavy metals in sludge (Cd, Cu, Fe, Mn, Ni, Pb, Zn) applied to the surface of soil columns containing barley plants. Half the columns received NaCl irrigation (10,000 mg L{sup -1}) and half the columns received tap-water irrigation. Half the columns were treated with the chelating agent EDTA. With no EDTA, irrigation with the NaCl solution increased the concentrations of Cd, Fe, Mn, and Pb in the drainage water above drinking-water standards. Irrigation of sludge farms with brackish water is not recommended, because saline water increased the mobility of the heavy metals and they polluted the drainage water. - Irrigation with brackish water mobilizes heavy metals in contaminated soils.

  15. Heavy metal displacement in salt-water-irrigated soil during phytoremediation

    International Nuclear Information System (INIS)

    In regions where phytoremediation is carried out, brackish water must often be used. However, no information exists concerning the consequences of saline-water irrigation on the mobility of heavy metals in sludge applied to soil during phytoremediation. The purpose of this experiment was to determine the effect of NaCl irrigation on displacement of seven heavy metals in sludge (Cd, Cu, Fe, Mn, Ni, Pb, Zn) applied to the surface of soil columns containing barley plants. Half the columns received NaCl irrigation (10,000 mg L-1) and half the columns received tap-water irrigation. Half the columns were treated with the chelating agent EDTA. With no EDTA, irrigation with the NaCl solution increased the concentrations of Cd, Fe, Mn, and Pb in the drainage water above drinking-water standards. Irrigation of sludge farms with brackish water is not recommended, because saline water increased the mobility of the heavy metals and they polluted the drainage water. - Irrigation with brackish water mobilizes heavy metals in contaminated soils

  16. Determination of Heavy Metal Levels in Various Industrial Waste Waters

    OpenAIRE

    Dündar, Mustafa Şahin; Altundağ, Hüseyin; Kaygaldurak, Sinem; Şar, Volkan; Acar, Aysun

    2012-01-01

    Important part of the environmetal pollution consists of waste water and water pollution. The water polluted by anthropogenical, industrial, and agricultural originated sources are defined as waste waters which are the main pollution sources for reservoirs, rivers, lakes, and seas. In this work, waste waters of leather, textile, automotive side, and metal plating industries were used to determine the levels of Cu, Zn, Cr, Pb and Ni by using Flame Atomic Absorption Spectrometer. As a result, h...

  17. Ground water quality evaluation near mining area and development of heavy metal pollution index

    Science.gov (United States)

    Prasad, Bably; Kumari, Puja; Bano, Shamima; Kumari, Shweta

    2014-03-01

    Opencast as well as underground coal mining are likely to disturb the underground water table in terms of quantity as well as quality. Added to this is the problem of leachates from the large number of industrial waste and overburden dumps that are in abundance in mining areas, reaching the ground water and adversely affecting its quality. Enhancement of heavy metals contamination of the ground water is one eventuality. In the present work, concentrations of 7 heavy metals have been evaluated at 20 important ground water sampling stations at Dhanbad township situated very near to Jharia coalfields. The concentration of heavy metals in general was found to be below the permissible levels although concentration of iron and manganese was found above the permissible limits at a few stations. These data have been used for the calculation of heavy metal pollution index (HPI). The HPI of ground water in total was found to be 6.8860 which is far below the critical index limit of 100 pointing to the fact that the ground water is not polluted with respect to heavy metals in spite of the prolific growth of mining and allied industrial activities near the town.

  18. Advances in optical water isotope ratio measurements

    International Nuclear Information System (INIS)

    Isotope ratio mass spectrometers routinely achieve impressive measurement precision and high throughput. In spite of this, a number of fundamental and practical problems are encountered. These are most notable in the case of water, arguably the most important molecule in the environment. Optical techniques to measure stable isotope ratios are able to address at least some of these issues; particularly, in relation to sample pretreatment and the difficulty of in-situ measurements. After discussing some general design criteria for infrared laser-based isotope ratio spectrometers, the case made above will be illustrated with a number of different instruments in applications from earthbound to the atmospheric: From laboratory based ice-core water isotope analyses to in-situ water isotope measurements in the upper troposphere and lower stratosphere. (author)

  19. Removal and recovery of heavy metals of residual water industrial

    International Nuclear Information System (INIS)

    On the next work the state of the art about the different methods and technologies for the present removal and recovery of heavy metals for the de-contamination and control of industrial wastewater is presented. Further more, it is introduce a removal alternative for chromium (III) and chromium (V I) using a solid waste material as an adsorbent, obtaining successful results which makes this proposal circumscribe into the clean technology program and residues bag

  20. Studies of water-in-oil emulsions : formation of water-in-oil states from heavy oils

    International Nuclear Information System (INIS)

    The formation of water-in-oil states from heavy oils was examined. Previous studies have demonstrated that viscosity is a significant factor affecting the formation and stability of water-in-oil emulsions. It was suggested that a viscosity window is a necessary requirement for the formation of stable emulsions. Highly viscous oils produce an entrained water state. A stable or meso-stable emulsion is rarely produced by heavy oils. In most cases, heavy oils result in an entrained water-in-oil state that lasts days longer than the entrained water-on-oil state of lighter oils. This can be explained by the lower migration rate of water droplets from a heavy oil compared to that of a light oil. These results were used to conduct an evaluation of the basis for using the stability index. This index provides a quantitative characterization of the stability of an emulsion, under varying formation regimes. The stability factor has been previously defined as the complex modulus of the water-in-oil state after emulsion formation, divided by the starting oil viscosity. It was shown that this stability factor remains a robust indicator, despite being less predictive in the case of heavy oils. The use of the newly developed stability scale produced values that were similar for water-in-oil states of both light and heavy oils. It was concluded that this new stability scale is complex, but the discriminating power over the old stability scale is not better. 6 refs., 6 tabs., 2 figs

  1. INCREASING HEAVY OIL RESERVES IN THE WILMINGTON OIL FIELD THROUGH ADVANCED RESERVOIR CHARACTERIZATION AND THERMAL PRODUCTION TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Scott Hara

    2004-03-05

    The overall objective of this project is to increase heavy oil reserves in slope and basin clastic (SBC) reservoirs through the application of advanced reservoir characterization and thermal production technologies. The project involves improving thermal recovery techniques in the Tar Zone of Fault Blocks II-A and V (Tar II-A and Tar V) of the Wilmington Field in Los Angeles County, near Long Beach, California. A primary objective is to transfer technology which can be applied in other heavy oil formations of the Wilmington Field and other SBC reservoirs, including those under waterflood. The thermal recovery operations in the Tar II-A and Tar V have been relatively inefficient because of several producibility problems which are common in SBC reservoirs. Inadequate characterization of the heterogeneous turbidite sands, high permeability thief zones, low gravity oil, and nonuniform distribution of remaining oil have all contributed to poor sweep efficiency, high steam-oil ratios, and early steam breakthrough. Operational problems related to steam breakthrough, high reservoir pressure, and unconsolidated formation sands have caused premature well and downhole equipment failures. In aggregate, these reservoir and operational constraints have resulted in increased operating costs and decreased recoverable reserves. The advanced technologies to be applied include: (1) Develop three-dimensional (3-D) deterministic and stochastic geologic models. (2) Develop 3-D deterministic and stochastic thermal reservoir simulation models to aid in reservoir management and subsequent development work. (3) Develop computerized 3-D visualizations of the geologic and reservoir simulation models to aid in analysis. (4) Perform detailed study on the geochemical interactions between the steam and the formation rock and fluids. (5) Pilot steam injection and production via four new horizontal wells (2 producers and 2 injectors). (6) Hot water alternating steam (WAS) drive pilot in the

  2. INCREASING HEAVY OIL RESERVES IN THE WILMINGTON OIL FIELD THROUGH ADVANCED RESERVOIR CHARACTERIZATION AND THERMAL PRODUCTION TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Scott Hara

    2003-06-04

    The overall objective of this project is to increase heavy oil reserves in slope and basin clastic (SBC) reservoirs through the application of advanced reservoir characterization and thermal production technologies. The project involves improving thermal recovery techniques in the Tar Zone of Fault Blocks II-A and V (Tar II-A and Tar V) of the Wilmington Field in Los Angeles County, near Long Beach, California. A primary objective is to transfer technology which can be applied in other heavy oil formations of the Wilmington Field and other SBC reservoirs, including those under waterflood. The thermal recovery operations in the Tar II-A and Tar V have been relatively inefficient because of several producibility problems which are common in SBC reservoirs. Inadequate characterization of the heterogeneous turbidite sands, high permeability thief zones, low gravity oil, and nonuniform distribution of remaining oil have all contributed to poor sweep efficiency, high steam-oil ratios, and early steam breakthrough. Operational problems related to steam breakthrough, high reservoir pressure, and unconsolidated formation sands have caused premature well and downhole equipment failures. In aggregate, these reservoir and operational constraints have resulted in increased operating costs and decreased recoverable reserves. The advanced technologies to be applied include: (1) Develop three-dimensional (3-D) deterministic and stochastic geologic models. (2) Develop 3-D deterministic and stochastic thermal reservoir simulation models to aid in reservoir management and subsequent development work. (3) Develop computerized 3-D visualizations of the geologic and reservoir simulation models to aid in analysis. (4) Perform detailed study on the geochemical interactions between the steam and the formation rock and fluids. (5) Pilot steam injection and production via four new horizontal wells (2 producers and 2 injectors). (6) Hot water alternating steam (WAS) drive pilot in the

  3. INCREASING HEAVY OIL RESERVES IN THE WILMINGTON OIL FIELD THROUGH ADVANCED RESERVOIR CHARACTERIZATION AND THERMAL PRODUCTION TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Scott Hara

    2003-09-04

    The overall objective of this project is to increase heavy oil reserves in slope and basin clastic (SBC) reservoirs through the application of advanced reservoir characterization and thermal production technologies. The project involves improving thermal recovery techniques in the Tar Zone of Fault Blocks II-A and V (Tar II-A and Tar V) of the Wilmington Field in Los Angeles County, near Long Beach, California. A primary objective is to transfer technology which can be applied in other heavy oil formations of the Wilmington Field and other SBC reservoirs, including those under waterflood. The thermal recovery operations in the Tar II-A and Tar V have been relatively inefficient because of several producibility problems which are common in SBC reservoirs. Inadequate characterization of the heterogeneous turbidite sands, high permeability thief zones, low gravity oil, and nonuniform distribution of remaining oil have all contributed to poor sweep efficiency, high steam-oil ratios, and early steam breakthrough. Operational problems related to steam breakthrough, high reservoir pressure, and unconsolidated formation sands have caused premature well and downhole equipment failures. In aggregate, these reservoir and operational constraints have resulted in increased operating costs and decreased recoverable reserves. The advanced technologies to be applied include: (1) Develop three-dimensional (3-D) deterministic and stochastic geologic models. (2) Develop 3-D deterministic and stochastic thermal reservoir simulation models to aid in reservoir management and subsequent development work. (3) Develop computerized 3-D visualizations of the geologic and reservoir simulation models to aid in analysis. (4) Perform detailed study on the geochemical interactions between the steam and the formation rock and fluids. (5) Pilot steam injection and production via four new horizontal wells (2 producers and 2 injectors). (6) Hot water alternating steam (WAS) drive pilot in the

  4. Licensing assessment of the Candu Pressurized Heavy Water Reactor. Preliminary safety information document. Volume II

    International Nuclear Information System (INIS)

    ERDA has requested United Engineers and Constructors (UE and C) to evaluate the design of the Canadian natural uranium fueled, heavy water moderated (CANDU) nuclear reactor power plant to assess its conformance with the licensing criteria and guidelines of the U.S. Nuclear Regulatory Commission (USNRC) for light water reactors. This assessment was used to identify cost significant items of nonconformance and to provide a basis for developing a detailed cost estimate for a 1140 MWe, 3-loop Pressurized Heavy Water Reactor (PHWR) located at the Middletown, USA Site

  5. Isotopic pollution of heavy water by contact with some organic materials

    International Nuclear Information System (INIS)

    The authors report a study which aimed at investigating the possible effect of isotopic exchange and pollution of heavy water due to a prolonged contact with organic compounds (oils, paints, plastics). This isotopic exchange capacity has been assessed by measuring the quantity of light water released by a surface sample of known weight, by determining the decrease in time of the isotopic level of a known quantity of high isotopic level heavy water in contact with the sample. Isotopic analyses have been performed by infrared spectrometry

  6. Licensing assessment of the Candu Pressurized Heavy Water Reactor. Preliminary safety information document. Volume II. [USA

    Energy Technology Data Exchange (ETDEWEB)

    1977-06-01

    ERDA has requested United Engineers and Constructors (UE and C) to evaluate the design of the Canadian natural uranium fueled, heavy water moderated (CANDU) nuclear reactor power plant to assess its conformance with the licensing criteria and guidelines of the U.S. Nuclear Regulatory Commission (USNRC) for light water reactors. This assessment was used to identify cost significant items of nonconformance and to provide a basis for developing a detailed cost estimate for a 1140 MWe, 3-loop Pressurized Heavy Water Reactor (PHWR) located at the Middletown, USA Site.

  7. Laser-induced breakdown spectroscopy detection of heavy metal in water based on graphite conch method

    Science.gov (United States)

    Wang, Chunlong; Liu, Jianguo; Zhao, Nanjing; Shi, Huan; Liu, Lituo; Ma, Mingjun; Zhang, Wei; Chen, Dong; Liu, Jing; Zhang, Yujun; Liu, Wenqing

    2012-10-01

    The laser-induced breakdown spectroscopy emission characteristics of trace heavy metal lead in water is studied based on graphite conch method, with a 1064nm wavelength Nd: YAG laser as excitation source, the echelle spectrometer and ICCD detector are used for spectral separation and high sensitive detection with high resolution and wide spectral range. The delay time 900ns and gate time 1600ns are determined in the experiment. The calibration curve of Pb is plotted based on the different concentration measurement results, and a limit of detection of 0.0138mg / L is obtained for Pb in water. Graphite conch method effectively overcomes the current problems on laser-induced breakdown spectroscopy detection of heavy metal in water. The detection limits and stability are improved. The reference data is provided for further study on the fast measurement of trace heavy metals in water by laser induced breakdown spectroscopy technique.

  8. Safety Evaluation of Osun River Water Containing Heavy Metals and Volatile Organic Compounds (VOCs) in Rats.

    Science.gov (United States)

    Azeez, L; Salau, A K; Adewuyi, S O; Osineye, S O; Tijani, K O; Balogun, R O

    2015-01-01

    This study evaluated the pH, heavy metals and volatile organic compounds (VOCs) in Osun river water. It also evaluated its safety in rats. Heavy metals were determined by atomic absorption spectrophotometry (AAS) while VOCs were determined by gas chromatography coupled with flame ionization detector (GC-FID). Male and female rats were exposed to Osun river water for three weeks and then sacrificed. The abundance of heavy metals in Osun river followed the trend Pb > Cd > Zn > Fe > Cr > Cu while VOCs followed the trend benzene water for three weeks had increased WBC, thiobarbituric acid reactive substances (TBARS), serum proteins and serum aminotransferases. There were also significant decreases in HCT, PLT, liver aminotransferases and liver glutathione compared to the control. These results show that the pollutants in Osun river water are capable of inducing hematological imbalance and liver cell injury. The toxicity induced in blood was sex-dependent affecting female rats more than male rats. PMID:27506174

  9. Water Quality and Heavy Metal Concentrations in Sediment of Sungai Kelantan, Kelantan, Malaysia: A Baseline Study

    International Nuclear Information System (INIS)

    A study on water quality and heavy metal concentration in sediment at selected sites of Sungai Kelantan was carried out. Ten water samples were collected along the river for physical and chemical analysis and twenty-six water and sediment samples were collected for heavy metal analysis. Water was sampled at three different dates throughout the study period whereas sediments were collected once. In addition to heavy metal analysis, sediment samples were also analysed for texture, ph and organic content. The physical and chemical water quality analyses were carried out according to the ALPHA procedures. Result of water quality analysis (physico-chemical) indicated that Sungai Kelantan is characterised by excellent water quality and comparable to pristine ecosystems such as the National Park and Kenyir Lake. This river was classified into class I - class III based on Malaysian interim water quality standard criteria (INWQS). Heavy metals Pb, Zn, Cu and Cd was detected at low concentration in sediment samples, except for Fe and Mn. The presence of Fe and Mn in sediment samples was though to be of natural origin from the soil. Anthropogenic metal concentrations in sediment were low indicating that Sungai Kelantan has not experienced extreme pollution. (author)

  10. Reduction of bioavailability and leachability of heavy metals during vermicomposting of water hyacinth.

    Science.gov (United States)

    Singh, Jiwan; Kalamdhad, Ajay S

    2013-12-01

    Vermicomposting of water hyacinth is a good alternative for the treatment of water hyacinth (Eichhornia crassipes) and subsequentially, beneficial for agriculture purposes. The bioavailability and leachability of heavy metals (Zn, Cu, Mn, Fe, Ni, Pb, Cd, and Cr) were evaluated during vermicomposting of E. crassipes employing Eisenia fetida earthworm. Five different proportions (trials 1, 2, 3, 4, and 5) of cattle manure, water hyacinth, and sawdust were prepared for the vermicomposting process. Results show that very poor biomass growth of earthworms was observed in the highest proportion of water hyacinth (trial 1). The water soluble, diethylenetriaminepentaacetic acid (DTPA) extractable, and leachable heavy metals concentration (percentage of total heavy metals) were reduced significantly in all trials except trial 1. The total concentration of some metals was low but its water soluble and DTPA extractable fractions were similar or more than other metals which were present in higher concentration. This study revealed that the toxicity of metals depends on bioavailable fraction rather than total metal concentration. Bioavailable fraction of metals may be toxic for plants and soil microorganisms. The vermicomposting of water hyacinth by E. fetida was very effective for reduction of bioavailability and leachability of selected heavy metals. Leachability test confirmed that prepared vermicompost is not hazardous for soil, plants, and human health. The feasibility of earthworms to mitigate the metal toxicity and to enhance the nutrient profile in water hyacinth vermicompost might be useful in sustainable land renovation practices at low-input basis. PMID:23757026

  11. The possibility for application of zeolite in the treatment of water contaminated with heavy metals

    OpenAIRE

    Golomeova, Mirjana; Krstev, Boris; Golomeov, Blagoj; Blažev, Krsto; Krstev, Aleksandar; Zendelska, Afrodita

    2013-01-01

    Heavy metals are one of the most serious threats to the aquatic environment. Mine drainage, which present complex of elements may cause various harmful effects on wildlife, but unfortunately are treat rare. There are many technologies for treating water contaminated with heavy metals, mainly divided into two broad categories: passive and active treatment. Passive treatments are cheaper and do not require special equipment or chemicals, while the active treatment are more complex and higher...

  12. DISTRIBUTION OF HEAVY METALS IN WATER AND SEDIMENT OF RATNAGIRI COAST, MAHARASHTRA.

    OpenAIRE

    Raju M. Patil; Sagar T. Sankpal; Pratap V. Naikwade

    2014-01-01

    Metals are commonly found in the environment all around the world, their presence being due to natural occurrence or as a result of anthropogenic activities. Heavy metals enter and contaminate coastal waters through industrial effluent, agriculture runoff, domestic sewage and mining activities along the coast. Ratnagiri is an important coastal area of Maharashtra; recently various activities have led to very high heavy metal concentrations on the coastal environment. They can ...

  13. Macrophytes in Phytoremediation of Heavy Metal Contaminated Water and Sediments in Pariyej Community Reserve, Gujarat, India

    OpenAIRE

    Kumar, J. I. Nirmal; Hiren SONI; Rita N. Kumar; Bhatt, Ira

    2008-01-01

    A phytoremediation study was carried out at Pariyej reservoir, an internationally important wetland listed in Asian Directory of Wetlands, designated as a "Wetland of International Importance" and a proposed community reserve of Gujarat State, India, to ascertain the degree of heavy metal contamination. The study focused on assessment of heavy metal accumulation in certain aquatic macrophytes used as biomonitors, in comparison with water and sediments (abiotic monitors) for phytorem...

  14. Radiological safety aspects: draining of heavy water during preparatory phase of proposed decommissioning of Cirus

    International Nuclear Information System (INIS)

    CIRUS reactor, the nucleus of nuclear programme of India was a 40 MWth research reactor, commissioned in July 1960. After five decades of valuable service to the nation, reactor was permanently shut down on 31st December 2010. The reactor used natural uranium as fuel and was cooled by demineralized water in a closed loop. The Heavy water (D2O) was used as moderator and helium gas was used as cover gas in the reactor vessel. Moderator system removed about 5% heat of the reactor power. This heat in turn was removed by sea water in heat exchangers. System tritium activity before permanent shutdown of Cirus reactor was 5.0 Ci/l. Tritium is the main radioactive isotope present in the moderator system which can cause internal hazards. During preparatory phase of decommissioning activities heavy water was drained from reactor vessel, heavy water heat exchangers, ion exchangers, different loops and instruments. Drained heavy water was transferred to storage tank no. 1 for interim storage. On the spot cold finger sampling was done to monitor tritium activity in air during and after each job related to handling of heavy water. Maximum tritium activity measured in air was 213 DAC. Internal dose due to tritium for all the jobs was 2.65 pmSv. This paper gives details about the radiological safe procedures followed, monitoring of tritium activity in air and internal dose assessment due to tritium during draining of heavy water from reactor moderator system. Implementation of operational practices and radiological safety coverage provided during the job resulted in low internal dose due to tritium and negligible rise in stack releases. (author)

  15. Assessment of irradiation effects on beryllium reflector and heavy water tank of JRR-3M

    Energy Technology Data Exchange (ETDEWEB)

    Murayama, Yoji; Kakehuda, Kazuhiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-10-01

    The JRR-3M, a swimming pool type research reactor with beryllium and heavy water reflectors, has been operated since 1990. Since the beryllium reflectors are close to fuel and receive high fast neutron fluence in a relatively short time, they may be subject to change their dimensions by swelling due mostly to entrapped helium gaseous. This may bend the reflectors to the outside and narrow gaps between the reflectors and the fuel elements. The gaps have been measured with an ultrasonic thickness gage in an annual inspection. The results in 1996 show that the maximum of expansion in the diametral directions was 0.6 mm against 1.6 mm of a managed value for replacement of the reflector. A heavy water tank of the JRR-3M is made of aluminum alloy A5052. Surveillance tests of the alloy have been conducted to evaluate irradiation effects of the heavy water tank. Five sets of specimens of the alloy have been irradiated in the beryllium reflectors where fast neutron flux is higher than that in the heavy water tank. In 1994, one set of specimens had been unloaded and carried out the post-irradiation tests. The results show that the heavy water tank preserved satisfactory mechanical properties. (author)

  16. Hot functional testing of the pressurized heavy water reactor plant Atucha II with light water

    International Nuclear Information System (INIS)

    The two pressurized heavy water reactors PHWR Atucha I (designed and built by S/KWU, now AREVA), and Atucha II (designed by S/KWU and plant construction now completed by NA-SA) are owned by Nucleoelectrica Argentina S.A. (NA-SA). Atucha II was designed in the 1980'ies in parallel to the two most recent S/KWU PWR generations Prekonvoi and Konvoi. Its basic design has been updated and optimized including also backfitting of components and systems for severe accident management. The gross electric power of the plant is 745 MWe. Construction and commissioning of Atucha II has been resumed by NA-SA after a work stop in the 1990'ies and is now almost completed. Hot functional testing HFT was performed in two phases in September and October 2013 and in March and April 2014. Hot functional testing was performed with light water and the fuel assemblies loaded. The chemistry program for the HFT was derived from practices and experience gathered at other S/KWU designed PWRs during HFTs and consisted of the following main targets and requirements: (1) Low chloride and sulfate concentrations close to normal operation values specified in the VGB water chemistry guideline for power operation of PWR plants; (2) Thorough oxygen removal during heat-up and reducing conditions through N2H4 dosing; (3) High pH value (target range 1.5 to 2 ppm Li); (4) Passivation treatment of the nuclear steam supply system NSSS at temperatures of at least 260°C for a time period of at least 120 hours; (5) Zinc addition at a constant rate of 20 g Zn per day throughout the various HFT phases. Zinc dosing was begun during the first heat-up of the plant at temperatures above approx. 150°C. Daily measurement of the zinc concentration for process control was not necessary and not required due to the elaborated zinc application procedure. The main results of the chemistry program for the HFT of plant are described and evaluated in this contribution. Data shows that all chemistry targets were met

  17. Study on accumulation of heavy metals in vegetables receiving sewage water

    International Nuclear Information System (INIS)

    A study was conducted to evaluate heavy metals content of sewage water and its impact on soil and vegetables. Thirty samples each of water, soil, and vegetable leaves and twenty-one samples of edible vegetable portions were collected from different sites, in between Peshawar city and Pakistan. Parameters like pH, and electrical conductivity (EC) were also determined. The pH of sewage water was slightly alkaline; electrical conductivity was with in the safe limit. Heavy metals Cu, Mn, Pb, and Cd, were detected but were found below the toxic level in soil. Levels of Fe, Ni, Cr, and Cd, were observed above the safe level in edible portion of plant while Cu, and Fe, concentrations exceeded in leaves. Zinc was found to be deficient in both water, and soil samples. All the tested heavy metals except Mn, and Cr were found more in fruits than in leaf and root of vegetables while Mn and Cr were found more in root. As some heavy metals were found in excessive amount in sewage water as well as in vegetables irrigated with this water. So it is recommended that vegetables directly consumed in raw form should not be grown with sewage water. (author)

  18. Recent Advances in Point-of-Access Water Quality Monitoring

    Science.gov (United States)

    Korostynska, O.; Arshak, K.; Velusamy, V.; Arshak, A.; Vaseashta, Ashok

    Clean water is one of our most valuable natural resources. In addition to providing safe drinking water it assures functional ecosystems that support fisheries and recreation. Human population growth and its associated increased demands on water pose risks to maintaining acceptable water quality. It is vital to assess source waters and the aquatic systems that receive inputs from industrial waste and sewage treatment plants, storm water systems, and runoff from urban and agricultural lands. Rapid and confident assessments of aquatic resources form the basis for sound environmental management. Current methods engaged in tracing the presence of various bacteria in water employ bulky laboratory equipment and are time consuming. Thus, real-time water quality monitoring is essential for National and International Health and Safety. Environmental water monitoring includes measurements of physical characteristics (e.g. pH, temperature, conductivity), chemical parameters (e.g. oxygen, alkalinity, nitrogen and phosphorus compounds), and abundance of certain biological taxa. Monitoring could also include assays of biological activity such as alkaline phosphatase, tests for toxins such as microcystins and direct measurements of pollutants such as heavy metals or hydrocarbons. Real time detection can significantly reduce the level of damage and also the cost to remedy the problem. This paper presents overview of state-of-the-art methods and devices used for point-of-access water quality monitoring and suggest further developments in this area.

  19. Safety Assessment of Pressure-Tube Heavy-Water Reactors by Probability Methods

    International Nuclear Information System (INIS)

    The use of probability methods for the assessment of safety has been developed in the United Kingdom for gas-cooled reactors; the development of these methods has proceeded in parallel with a move towards the formulation of quantitative safety criteria; some possible criteria are described. In particular, a method has been developed which is of value for a rapid assessment of a preliminary design in order to reveal potential points of weakness before the design is finalized. The method is of general application and in this paper it is applied to the design of hypothetical 250-MW(e) reactors of both the indirect and direct cycle types in order to illustrate the use of this method for pressure-tube heavy-water reactors and also to provide a comparison of the safety of this reactor system and others, such as the United Kingdom advanced gas-cooled type. A difficulty in the use of probability methods at present is the scarcity of data on failure rates for structures and large items of plant. An essential feature of the method described is a perturbation of the assumed failure rates by factors of order 100, to assess the effect of such uncertainties. The effect of major changes in other features important to safety, such as reliability of the containment systems, is also examined. (author)

  20. Advanced Methods for Treatment of Organic Compounds Contamined Water

    OpenAIRE

    PREDESCU Andra; A.Predescu; Ecaterina MATEI

    2009-01-01

    The progress recorded in the field of science and advanced engineering at nanometric scale supplies largeopportunities for more efficient (from the point of view of the costs) and more ecological approach of the processes ofwater purifying. This paper delivers a short description of the possibilities of using advanced materials in purifying thecontamined water with toxic metallic ions, organic and anorganic compounds. The opportunities and challenges werealso emphasized when nanomaterials wer...

  1. Contribution of Heavy Water Board in nuclear fuel cycle technologies. Contributed Paper IT-03

    International Nuclear Information System (INIS)

    The three stage Indian nuclear power programme envisages use of closed nuclear fuel cycle and thorium utilization as its mainstay for long term energy security on sustainable basis. India is committed to realize this objective through the development and deployment of frontier technologies pertaining to all aspects of a closed nuclear fuel cycle. Comprehensive indigenous capabilities have been developed in all aspects of nuclear power and associated fuel cycles. Heavy Water Board (HWB), with its abiding objective of fulfilling demand of heavy water for India's flourishing nuclear power program, is one of the frontrunner in Nuclear Fuel Cycle Technology. HWB is now engaged in wide spectrum of activities in various facets of fuel cycle covering all the three stages of Indian Nuclear Power Programme. HWB is contributing to Nuclear Fuel Cycle through large scale production and sustained supply of key input materials including heavy water, solvents for nuclear hydrometallurgy, 10B enriched boron etc

  2. Quantification and validation of large-scale gas sealed high isotopic purity heavy water reference standards

    International Nuclear Information System (INIS)

    The isotopic purity of helium gas sealed heavy water reference standards prepared here on a large scale in the high concentration range has been estimated employing FT-IR method standardized with certified D2O standard and confirmed by validation using the same method with supplementary certified standard having its purity value declared from a different method - FT-NMR spectroscopy, each of the certified standards having an accuracy of ± 0.01 wt.%. The same quantification and validation procedure has been well applied to declare the purity values of large - scale reference standards (99.86 wt.%, 99.90 wt.% and 99.96 wt.%) jointly prepared with Heavy Water Plant (HWP) Laboratory, Baroda to analyze high concentration heavy water samples with same level of accuracy and reproducibility for all the HWP laboratories in India. (author)

  3. D20PROP- computer code for determination of heavy water properties

    International Nuclear Information System (INIS)

    An accurate determination of heavy water properties plays a significant role in various thermal hydraulic analyses. Determination of thermophysical properties of heavy water has evolved over a number of years. Reactor Safety Division has participated in IAEA coordinated research project and arrived at formulations for heavy water based on IAPS formulations. However, safety analysis codes like RELAP IV/MOD6 and COHRA needs few more formulations and over extended range and hence additional verifications. In view of this a computer code D2OPROP has been developed. Formulations developed in this code are general, so that any desired thermodynamic property can be evaluated in future, which is not presented in this report. This code has been compared with various reference data for all properties over the entire range. It has also been used to generate properties that are required as inputs to different safety analysis codes. This report describes various formulation used in the code, its uses and its inputs. (author)

  4. The development of reactor vessel internal heavy forging for 1000 MW pressurized-water reactor nuclear power plant

    International Nuclear Information System (INIS)

    This Paper introduced the development of Reactor Vessel Internal (RVI) heavy forgings for 1000 MW Pressurized Water Reactor (PWR) nuclear power plant, analyzed the manufacture difficulties and technical countermeasures. The testing result of the product indicated that the performance of RVI heavy forgings manufactured by Shanghai Heavy Machinery Plant Ld. (SHMP) is outstanding and entirely satisfy the technical requirements for RVI product. (authors)

  5. Antifoaming materials in G.S. (Girlder sulfide) heavy water plants. Thermical stability. Pt. 2

    International Nuclear Information System (INIS)

    In Girlder sulfide (G.S.) heavy water plants hydrogen sulfide-water systems are inherentely foaming, so the adding of antifoaming materials is of great importance. These may be of high volatility, pyrolizable or chemically unstable in plant operation conditions (water and hydrogen sulfide at 2 MPa, up to 230 deg C). About twenty commercial surfactants were studied from the point of view of their thermical stability. (Author)

  6. Determination of the tritium content in the reactor heavy water, Phase II

    International Nuclear Information System (INIS)

    Measurement results of the 3H activity in non-irradiated water and after reactor operation are presented. Methods were developed for sampling and radiochemical water purification by ion exchange and multiple distillation. Methods for absolute measurement of soft beta radiation of tritium were established. Migration of tritium through the heavy water RA reactor system was monitored. Results were compared with other measured reactor parameters

  7. Designing a plant for tritium and protium removal from heavy water of the PIK reactor

    International Nuclear Information System (INIS)

    The project of the facility for tritium and protium isotopic removal (FIR) from the PIK reactor heavy water is described. The FIR principle scheme, wherein different methods for isotopes separation and management of deuterium, contaminated by tritium are applied, is presented. The experimental facilities created for obtaining the initial data required for the FIR project development are described. In particular, the facility for the hydrogen isotopes separation is created on the basis of the isotope exchange between water and hydrogen and water electrolysis

  8. Assessment of heavy metal concentrations in water, plankton, and fish of Lake Manzala, Egypt

    OpenAIRE

    BAHNASAWY, Mohamed; KHIDR, Abdel-Aziz; DHEINA, Nadia

    2011-01-01

    The levels of some heavy metals (Cu, Zn, Cd, and Pb) were determined in water, plankton, and fish (Liza aurata) collected from 5 sites in Lake Manzala. Metals in the water and fish exhibited a significant seasonal and regional variation, in which all metals attained their maximum value during summer, while the lowest levels were found during winter. The concentration of different metals in water, plankton, and fish tissues followed the same order: Zn > Cu > Pb > Cd. The mean concentr...

  9. The study heavy metals in water,soil and Vegatable in Shahroud

    Directory of Open Access Journals (Sweden)

    saied Nazemi

    2011-01-01

    Full Text Available Introduction: The arrival of toxic metals by human activities has lead to the contamination of soil. Heavy metals are among the most important pollutants in the environment. This study aimed at determining the concentration of heavy metals in soils, water and vegetables of Shhnama region in Shahroud. Methods: Vegetables studied included parsley, leek, leaf beet, fenugreek, cress, basil, radish and the coriander. The sampling was performed during 3 months, from September to October, 2008. The collected 180 samples of vegetables, water, soil, after preparation by atomic absorption Spectrophotometers, were analyzed according to standard methods. Results: Mean concentration values of lead, cadmium, chromium, arsenic and zinc in vegetable samples were, respectively 23.99, 2.09, 5.4, 5.26, 168.4 micrograms per gram of plant tissue. Mean concentrations of heavy metals in water were, respectively, 7.55, 4.85, 0.78, 12.83 and 347.99 mg per liter in water samples. Mean concentrations of heavy metals in soil were, respectively, 81.12, 14.43, 134.32, 19.08 and 435 micrograms, per gram of soil sample. Comparing the mean concentration values for heavy metals available in vegetables, water and soil with standard values, significant differences are observed except for Zn. Concentration values of lead, cadmium, chromium and arsenic in vegetables were higher than the common values. Conclusion: The results indicate that due to the use of synthetic fertilizers, unsanitary disposal of sewage and fossil fuel combustion, water, soil and plants of the region are polluted with heavy metals.

  10. Feasibility study and economic analysis on thorium utilization in heavy water reactors

    International Nuclear Information System (INIS)

    Even though natural uranium is a more easily usable fuel in heavy water reactors, thorium fuel cycles have also been considered owing to certain attractive features of the thorium fuel cycle in heavy water reactors. The relatively higher fission neutron yield per thermal neutron absorption in 233U combined with the very low neutron absorption cross section of heavy water make it possible to achieve breeding in a heavy water reactor operating on Th-233U fuel cycle. Even if the breeding ratio is very low, once a self-sustaining cycle is achieved, thereafter dependence on uranium can be completely eliminated. Thus, with a self-sustaining Th-233U fuel cycle in heavy water reactors, a given quantity of natural uranium will be capable of supporting a much larger installed generating capacity to significantly longer period of time. However, since thorium does not contain any fissile isotope, fissile material has to be added at the beginning. Concentrated fissile material is considerably more expensive than the 235U contained in natural uranium. This makes the fuel cycle cost higher with thorium fuel cycle, at least during the initial stages. The situation is made worse by the fact that, because of its higher thermal neutron absorption cross section, thorium requires a higher concentration of fissile material than 238U. Nevertheless, because of the superior nuclear characteristics of 233U, once uranium becomes more expensive, thorium fuel cycle in heavy water reactors may become economically acceptable. Furthermore, the energy that can be made available from a given quantity of uranium is considerably increased with a self-sustaining thorium fuel cycle

  11. Performance of refractometry in quantitative estimation of isotopic concentration of heavy water in nuclear reactor

    International Nuclear Information System (INIS)

    Highlights: ► Rapid analysis of heavy water samples, with precise temperature control. ► Entire composition range covered. ► Both variations in mole and wt.% of D2O in the heavy water sample studied. ► Standard error of calibration and prediction were estimated. - Abstract: The method of refractometry has been investigated for the quantitative estimation of isotopic concentration of heavy water (D2O) in a simulated water sample. Feasibility of refractometry as an excellent analytical technique for rapid and non-invasive determination of D2O concentration in water samples has been amply demonstrated. Temperature of the samples has been precisely controlled to eliminate the effect of temperature fluctuation on refractive index measurement. The method is found to exhibit a reasonable analytical response to its calibration performance over the purity range of 0–100% D2O. An accuracy of below ±1% in the measurement of isotopic purity of heavy water for the entire range could be achieved

  12. Determination of Heavy Metal Levels in Various Industrial Waste Waters

    Directory of Open Access Journals (Sweden)

    Mustafa Şahin Dündar

    2012-06-01

    Full Text Available Important part of the environmetal pollution consists of waste water and water pollution. The water polluted by anthropogenical, industrial, and agricultural originated sources are defined as waste waters which are the main pollution sources for reservoirs, rivers, lakes, and seas. In this work, waste waters of leather, textile, automotive side, and metal plating industries were used to determine the levels of Cu, Zn, Cr, Pb and Ni by using Flame Atomic Absorption Spectrometer. As a result, highest mean levels of copper in supernatants of plating and textile industries were observed as 377,18 ng ml-1, respectively 103 ng ml-1 lead and 963,6 ng ml-1 nickel in plating industry, 1068,2 ng ml-1 zinc and 14557,1 ng ml-1 chromium in plating and leather industries were determined.

  13. AECB staff annual assessment of the Bruce Heavy Water Plant for the year 1996

    International Nuclear Information System (INIS)

    The Atomic Energy Control Board is the independent federal agency that controls all nuclear activities in Canada. Heavy water is an essential part of Canada's nuclear industry and the AECB regulates its production. The AECB staff assess every facilities performance against legal requirements, including the conditions in the operating licence issued. All aspects of the facility's operation and management are reviewed and each facility is inspected. This report is the AECB staff assessment of the operation of the Bruce Heavy Water Plant during 1996. The operation was safe in 1996 and Ontario Hydro complied with the regulations. The emergency response capability was found satisfactory

  14. The simulation of stationary and non-stationary regime operation of heavy water production facilities

    International Nuclear Information System (INIS)

    This paper refers to testing procedures of the production capacity of heavy water production pilot, industrial scale plants and of heavy water reconcentration facilities. Simulation codes taking into account the mass and heat transfers inside the exchange columns were developed. These codes provided valuable insight about the isotope build-up of the installation which allowed estimating the time of reaching the stationary regime. Also transient regimes following perturbations in the operating parameters (i.e. temperature, pressure, fluid rates) of the installation were simulated and an optimal rate of routine inspections and adjustments was thus established

  15. HEAVY METAL ANALYSIS IN WASTE WATER SAMPLES FROM VALEA ŞESEI TAILING POND

    OpenAIRE

    I. L. MELENTI; E. MAGYAR; T. RUSU

    2011-01-01

    Heavy metal analysis in waste water samples from Valea Şesei tailing pond. The mining of ore deposits and the processing and smelting of copper at Roşia Poieni have resulted in an increase of the toxic elements concentration within all components of the environment in the area. Valea Şesei tailing pond is a waste deposit for the Roşia Poieni open-pit and is the biggest tailing pond in Romania. In October 2009, we determined 8 heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Ni and Zn) in 10 waste water ...

  16. Selection of the process for the heavy water production using isotopic exchange amonia-hydrogen

    International Nuclear Information System (INIS)

    The utilization of the Petroleos Mexicanos ammonia plants for heavy water production by the isotopic exchange NH3-H2 process is presented, in addition a description of the other heavy water production processes was presented. In the ammonia hydrogen process exist two possible alternatives for the operation of the system, one of them is to carry out the enrichment to the same temperature, the second consists in making the enrichment at two different temperatures (dual temperature process), an analysis was made to select the best alternative. The conclusion was that the best operation is the dual temperature process, which presents higher advantages according to the thermodynamics and engineering of the process. (author)

  17. Advanced Water-Gas Shift Membrane Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sean Emerson; Thomas Vanderspurt; Susanne Opalka; Rakesh Radhakrishnan; Rhonda Willigan

    2009-01-07

    The overall objectives for this project were: (1) to identify a suitable PdCu tri-metallic alloy membrane with high stability and commercially relevant hydrogen permeation in the presence of trace amounts of carbon monoxide and sulfur; and (2) to identify and synthesize a water gas shift catalyst with a high operating life that is sulfur and chlorine tolerant at low concentrations of these impurities. This work successfully achieved the first project objective to identify a suitable PdCu tri-metallic alloy membrane composition, Pd{sub 0.47}Cu{sub 0.52}G5{sub 0.01}, that was selected based on atomistic and thermodynamic modeling alone. The second objective was partially successful in that catalysts were identified and evaluated that can withstand sulfur in high concentrations and at high pressures, but a long operating life was not achieved at the end of the project. From the limited durability testing it appears that the best catalyst, Pt-Re/Ce{sub 0.333}Zr{sub 0.333}E4{sub 0.333}O{sub 2}, is unable to maintain a long operating life at space velocities of 200,000 h{sup -1}. The reasons for the low durability do not appear to be related to the high concentrations of H{sub 2}S, but rather due to the high operating pressure and the influence the pressure has on the WGS reaction at this space velocity.

  18. Removal of heavy metal ions from oil shale beneficiation process water by ferrite process

    Energy Technology Data Exchange (ETDEWEB)

    Mehta, R.K.; Zhang, L.; Lamont, W.E.; Schultz, C.W. (Alabama Univ., University, AL (United States). Mineral Resources Inst.)

    1991-01-01

    The ferrite process is an established technique for removing heavy metals from waste water. Because the process water resulting from oil shale beneficiation falls into the category of industrial waste water, it is anticipated that this process may turn out to be a potential viable treatment for oil shale beneficiation process water containing many heave metal ions. The process is chemoremedial because not only effluent water comply with quality standards, but harmful heavy metals are converted into a valuable, chemically stable by-product known as ferrite. These spinel ferrites have magnetic properties, and therefore can be use in applications such as magnetic marker, ferrofluid, microwave absorbing and scavenging material. Experimental results from this process are presented along with results of treatment technique such as sulfide precipitation.

  19. Removal of heavy metal ions from oil shale beneficiation process water by ferrite process

    Energy Technology Data Exchange (ETDEWEB)

    Mehta, R.K.; Zhang, L.; Lamont, W.E.; Schultz, C.W. [Alabama Univ., University, AL (United States). Mineral Resources Inst.

    1991-12-31

    The ferrite process is an established technique for removing heavy metals from waste water. Because the process water resulting from oil shale beneficiation falls into the category of industrial waste water, it is anticipated that this process may turn out to be a potential viable treatment for oil shale beneficiation process water containing many heave metal ions. The process is chemoremedial because not only effluent water comply with quality standards, but harmful heavy metals are converted into a valuable, chemically stable by-product known as ferrite. These spinel ferrites have magnetic properties, and therefore can be use in applications such as magnetic marker, ferrofluid, microwave absorbing and scavenging material. Experimental results from this process are presented along with results of treatment technique such as sulfide precipitation.

  20. Investigations for heavy metals pollution in the Nile water in Khartoum area using XRF

    International Nuclear Information System (INIS)

    The purpose of this study was to perform measurements for heavy metals pollution in the Nile water in Khartoum area. Ten locations were selected for the study on the white Nile, the Blue Nile and the Nile. Standard methods were used for samples collection and preparation for the measurements using XRF. Nine elements were observed and their concentrations determined in the various locations. These Ti, Cr, Fe, Cu, Zn, As, Pb, Zr, and Se. From the performed measurements for heavy metals pollution in the Nile water in Khartoum area using the XRF method the following conclusions can be made: There is no heavy metal pollution in the Nile water in Khartoum area resulting from industrial activities. However, there are indications for possible Pb pollution resulting from automobile emission. - The concentrations for the observed heavy metals, except Fe, were much below the maximum permissible international levels provided by the USA, EEC and WHO. - The origin for the observed concentrations of heavy metals, except for Pb, was considered to be soil and silt carried by river in it's journey from the Ethiopian Highlands and lake Victoria. (Author)

  1. Phytoremediation of heavy metal-contaminated water and sediment by eleocharis acicularis

    Energy Technology Data Exchange (ETDEWEB)

    Sakakibara, Masayuki; Ha, Nguyen Thi Hoang [Graduate School of Science and Engineering, Ehime University, Matsuyama (Japan); Ohmori, Yuko [Graduate School of Science and Engineering, Ehime University, Matsuyama (Japan); Taisei Kiso Sekkei Co., Ltd., Tokyo (Japan); Sano, Sakae [Faculty of Education, Ehime University, Matsuyama (Japan); Sera, Koichiro [Cyclotron Center, Iwate Medical University, Takizawa-mura (Japan)

    2011-08-15

    Phytoremediation is an environmental remediation technique that takes advantage of plant physiology and metabolism. The unique property of heavy metal hyperaccumulation by the macrophyte Eleocharis acicularis is of great significance in the phytoremediation of water and sediments contaminated by heavy metals at mine sites. In this study, a field cultivation experiment was performed to examine the applicability of E. acicularis to the remediation of water contaminated by heavy metals. The highest concentrations of heavy metals in the shoots of E. acicularis were 20 200 mg Cu/kg, 14 200 mg Zn/kg, 1740 mg As/kg, 894 mg Pb/kg, and 239 mg Cd/kg. The concentrations of Cu, Zn, As, Cd, and Pb in the shoots correlate with their concentrations in the soil in a log-linear fashion. The bioconcentration factor for these elements decreases log-linearly with increasing concentration in the soil. The results indicate the ability of E. acicularis to hyperaccumulate Cu, Zn, As, and Cd under natural conditions, making it a good candidate species for the phytoremediation of water contaminated by heavy metals. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Physical and water properties of selected Polish heavy soils of various origins

    Directory of Open Access Journals (Sweden)

    Kaczmarek Zbigniew

    2015-12-01

    Full Text Available The paper presents the characteristics of selected physical, chemical, and water properties of four mineral arable soils characterized with heavy and very heavy texture. Soil samples from genetic horizons of black earths from areas near Kętrzyn, Gniew and Kujawy, and alluvial soils from Żuławy were used. The following properties were determined in the samples of undisturbed and disturbed structure: texture, particle density, bulk density, porosity, natural and hygroscopic moistures, maximal hygroscopic capacity, saturated hydraulic conductivity, potential of water bonding in soil, total and readily available water, total retention in the horizon of 0–50 cm, drainage porosity, content of organic carbon and total nitrogen Parent rocks of these soils were clays, silts and loams of various origin. High content of clay fraction strongly influenced the values of all the analyzed properties. All the examined soils had high content of organic carbon and total nitrogen and reaction close to neutral or alkaline. High content of mineral and organic colloids and, what follows, beneficial state of top horizons’ structure, determined – apart from heavy texture – low soil bulk density and high porosity. The investigated soils were characterized by high field water capacity and wide scopes of total and readily available water. The saturated hydraulic conductivity was low and characteristic to heavy mineral arable soils. The parameter which influenced the variability of analyzed parameters most was texture.

  3. Three-component U-Pu-Th fuel for plutonium irradiation in heavy water reactors

    Directory of Open Access Journals (Sweden)

    Peel Ross

    2016-01-01

    Full Text Available This paper discusses concepts for three-component fuel bundles containing plutonium, uranium and thorium for use in pressurised heavy water reactors, and cases for and against implementation of such a nuclear energy system in the United Kingdom. Heavy water reactors are used extensively in Canada, and are deploying within India and China, whilst the UK is considering the use of heavy water reactors to manage its plutonium inventory of 140 tonnes. The UK heavy water reactor proposal uses a mixed oxide (MOX fuel of plutonium in depleted uranium, within the enhanced CANDU-6 (EC-6 reactor. This work proposes an alternative heterogeneous fuel concept based on the same reactor and CANFLEX fuel bundle, with eight large-diameter fuel elements loaded with natural thorium oxide and 35 small-diameter fuel elements loaded with a MOX of plutonium and reprocessed uranium stocks from UK MAGNOX and AGR reactors. Indicative neutronic calculations suggest that such a fuel would be neutronically feasible. A similar MOX may alternatively be fabricated from reprocessed <5% enriched light water reactor fuel, such as the fuel of the AREVA EPR reactor, to consume newly produced plutonium from reprocessing, similar to the DUPIC (direct use of PWR fuel in CANDU process.

  4. Advances in Membrane Distillation for Water Desalination and Purification Applications

    OpenAIRE

    Juan Gomez; Stephen Gray; Jun-de Li; Mikel Duke; Jianhua Zhang; Ludovic Dumée; Lucy Mar Camacho

    2013-01-01

    Membrane distillation is a process that utilizes differences in vapor pressure to permeate water through a macro-porous membrane and reject other non-volatile constituents present in the influent water. This review considers the fundamental heat and mass transfer processes in membrane distillation, recent advances in membrane technology, module configurations, and the applications and economics of membrane distillation, and identifies areas that may lead to technological improvements in membr...

  5. Extending the product variety at ROMAG-PROD Heavy Water Plant

    International Nuclear Information System (INIS)

    Full text: Having in mind that the prospects of operating the ROMAG-PROD Heavy Water Plant are conditioned by both the heavy water market demand and the wear of the equipment which is exposed to hydrogen sulfide-induced corrosion, some possibilities were considered to extend the assortment of products, the production of which could ensure the plant's operation on long term. The proposals here refer to promoting the efficient production of oxygen-isotope-based products which would optimize maximally the exploit of available raw materials, supply and utilities of the ROMAG compound. The market manifests a significant demand of water enriched in the 18O isotope up to 95-97% purity that is used in Positron Emission Tomography (PET). This oxygen isotope is also used as a labelling agent in studies of reaction mechanisms and paleo-climatologic studies as well. Some research evidenced the superconducting properties of some oxygen compounds containing the 18O isotope. The isotope 17O has applications in Nuclear Magnetic Resonance (NMR) as being the sole oxygen isotope endowed with a nuclear magnetic moment. On the other hand, it was found that although the 16O isotope has a natural abundance of 99.8%, applications exist that require the absolute purity of this isotope i.e. the elimination of the other oxygen isotopes as is the case of fission reactors with Plutonium dioxide as nuclear fuel. The methods applied on industrial scale for enriching the oxygen isotopes are based on distillation of some oxygen compounds such as water and nitrogen monoxide. The possibility of a supplementary distillation of the heavy water at a distillation line of ROMAG-PROD Heavy Water Plant was considered in order to enrich the heavy water in the 17O and 18O isotopes up to an upper limit of 2-5% for 18O. Obtaining the heavy isotopes of oxygen by distillation of heavy water is characterized by several aspects as the following ones: a high specific consumption of steam due to both the low

  6. Analysis of heavy water lattice experiments on research reactors for testing nuclear data

    International Nuclear Information System (INIS)

    There is a need for updated multigroup libraries for lattices codes of WIMS type for PHWR reactors calculations. Different multigroup libraries are used with WIMS and other codes, but these libraries are not normally updated to the level of last revision of ENDF/B-VI and other evaluated nuclear data files. Then, a special attention to the application of new WIMS libraries on PHWR calculations is justified. Some research and development activities associated to PHWR type of reactors, that need updated nuclear libraries of WIMS type, are: use of slightly enriched uranium (SEU cycle), use of UO2-ThO2 fuels, use of burnable poisons mixed in fuel pellets (UO2-Gd2O3) and absorber rods, new types of fuel elements (in Argentina: CARA Project-Advanced Fuel for Argentine Reactors) Taking into account the need of new WIMS libraries associated to these activities, a set of benchmarks have been identified and coded for PHWR lattice calculations.. The experimental benchmarks are identified with the name of the facility or research reactor where the measurements were carried out. The main references for this type of benchmarks is the ZED-2 Canadian reactor and DCA Japanese reactor. This work cover benchmark results of the following cases: ZED-2 analysis: experiments with 37 and 28 CANDU-type rod Fuel Clusters and lattice experiments with 19-rod Clusters with ThO2-UO2 Fuel; DCA analysis: Evaluation of Neutronic Parameters in Heavy Water and Slightly Enriched Uranium UO2 Fuel (28-rod Cluster) and critical experiments on Gadolinium poisoned cluster-type fuel assemblies of 54 rods in heavy water lattices of DCA facility. For several cases, results are included for different pitches and coolants. The parameters analysed are: k-effective with experimental bucklings, fast fission ratio [U-238 fissions/U-235 fissions], relative conversion ratio [U-238 captures/U-235 fissions], U-235 fission rate distribution, Cu-63 absorption rate distribution, Lutetium-Manganese activity ratio, ratio of

  7. Study on the Effects of Irrigation with Reclaimed Water on the Content and Distribution of Heavy Metals in Soil

    Directory of Open Access Journals (Sweden)

    Shibao Lu

    2016-03-01

    Full Text Available Reclaimed water is an important resource for irrigation, and exploration in making full use of it is an important way to alleviate water shortage. This paper analyzes the effects of irrigation with reclaimed water through field trials on the content and distribution of heavy metals in both tomatoes and the soil. By exploring the effects of reclaimed water after secondary treatment on the content and distribution characteristics of heavy metals in tomatoes and the heavy metal balance in the soil-crop system under different conditions, the study shows that there are no significant differences in the heavy metal content when the quantity of reclaimed water for irrigation varies. Reclaimed water for short-term irrigation does not cause pollution to either the soil environment or the crops. Nor will it cause the accumulation of heavy metals, and the index for the heavy metal content is far below the critical value of the national standard, which indicates that the vegetables irrigated with reclaimed water during their growth turn out to be free of pollutants. The heavy metals brought into the soil by reclaimed water are less than that taken away by the crops. The input and output quantities have only small effects on the heavy metal balance in the soil. This paper provides a reference for the evaluation and safety control of irrigation with reclaimed water.

  8. Advance directives, dementia, and withholding food and water by mouth.

    Science.gov (United States)

    Menzel, Paul T; Chandler-Cramer, M Colette

    2014-01-01

    People with dementia who are no longer competent have limited control over how their lives end. But an advance directive to withhold food and water by mouth could be used to ensure that one does not live for years in severe dementia. Such directives are arguably already legal. PMID:24821250

  9. EVALUATION OF HEAVY METAL IN COASTAL WATER AT KELANTAN

    OpenAIRE

    Rizki Wannahari; Nurul Ain Abdullah; Mariam Firdhaus Mad Nordin; Marinah Muhammad

    2013-01-01

    Five sites were selected representing the studied sites of the coastal water in Kelantan, Malaysia during 1996 until May 2012. These selected sites are the popular beaches in Kelantan which are Sri Tujuh Beach (STB) located in Tumpat region, Cahaya Bulan Beach (PCB) and Sabak Beach (SB) in Kota Bharu region, Irama Beach (PI) in Bachok region and Bisikan Bayu Beach (PBB) in Pasir Putih region. In other to identify the quality of coastal water in this five popular coasts along Kelantan, study o...

  10. Water and Sediment Heavy Metal Pollution in Ereniku River of Kosovo

    Directory of Open Access Journals (Sweden)

    FATON MALOKU

    2015-06-01

    Full Text Available Soil, water and sediment samples were collected in 13 sampling stations along Erenik River, in the western part of Kosovo in order to assess heavy metal pollution. The concentration of hevy metals as Cd, Hg, Pb, Cr, Cu and Zn were determinated in water, soil and sediment samples. The concentration of heavy metals in water samples was measured using the flame atomic absorption spectrophotometer (AAS, while for sediment and soil samples was used inductively coupled plasma mass spectrometry (ICP-MS. Obtained results showed that the concentrations in soil of heavy metals Cd, Pb, Cu and Zn were under the proposed limit values by the European guideline for “soil background", while the obtained values of Cr in all stations were higher than proposed limit values. The concentrations of heavy metals in sediment were often higher than the values determined with low action on the biological systems of the river ecosystem (ERL Effect Range Low but smaller than the values that negatively affecting the extent > 50% of organisms on core Effect Medium Range - ERM (Cu, Pb and Ni. The total values of Cr were higher than ERM but its origin is mainly geological more than human activities, thus the biological effect of this element can be probably low. Our results indicated that heavy metals as Pb, Zn and Cu were found in high portion in fine sediment fraction (<0.2 mm, while Cr, Ni and Co were in low amount in this sediment fraction. The concentrations of all analyzed heavy metals in the water were generally low at the beginning of the flow, average in middle stations and higher in secondary stations. Furthermore, the values for Pb, Cd, Cu and Zn were higher than international standards in some stations, showing the influence of highly polluted streams that join Erenik River flow in these stations.

  11. Heavy metal and radioactivity measurements in fish, water, plants and soils in tin-mining pool

    International Nuclear Information System (INIS)

    Malaysia aggressively reclaimed most of their disused tin-mining pool especially for agricultural activities, freshwater fish farming area, recreational area, houses area and even as an industrial area. Past mining activities might induced the concentration of naturally occurring radionuclide (NORM) and heavy metal at the disused tin-mining pool ecosystem. A study has been conducted on the status of heavy metal (Hf, Zr, Mn, Cu, Zn, As, Cd, Sn, Sb, Ba, Hg and Pb) concentration and naturally occurring radionuclide activity in fish, water, plants and sediments at three different disused tin-mining pool near by Sepang and Puchong, Selangor Darul Ehsan. Sample of fish, water, plant and sediment being analyze using ICP-MS. The concentrations of heavy metal in sediment and plant are higher than its concentrations in fish and followed by water. The highest concentration of heavy metal in sediment and water is barium, whereas the highest concentration of heavy metal in fish and plant is zinc and manganese. The result also showed that only mercury level in fish collected in second disused tin-mining pool (0.53 ± 0.20 mg/ kg) is exceed the maximum limit (0.5 mg/ kg) prescribe by the Malaysian Food Act (Act 281). The activity of U-238 and Th-232 in sediment was found to be relatively higher than its activity in fish, plant or water (30.76 ± 2.71 to 35.34 ± 0.27 Bq/ kg) and (9.37 ± 2.30 - 18.86 ± 2.60 Bq/ kg). The determination of K-40 activity showed that it is highly contained in plant and fish than in sediment or water. (author)

  12. Evaluation of surface water quality indices and ecological risk assessment for heavy metals in scrap yard neighbourhood

    OpenAIRE

    Ojekunle, Olusheyi Z.; Ojekunle, Olurotimi V.; Adeyemi, Azeem A.; Taiwo, Abayomi G.; Sangowusi, Opeyemi R.; Taiwo, Adewale M.; Adekitan, Adetoun A.

    2016-01-01

    Pollution of surface water with heavy metals from industrial activities especially those from scrap yard has caused a major threat to human life exposing man to series of hazard, diseases, disability and consequently death. This study focuses on water quality indices of Owode-Onirin and Lafenwa scrap yard with respect to its physicochemical parameters and heavy metal concentrations by evaluating Heavy Metal Pollution Index (HPI), Metal Index (MI) and Potential Ecological Risk Index (PERI). Fi...

  13. Benchmarking Severe Accident Computer Codes for Heavy Water Reactor Applications

    International Nuclear Information System (INIS)

    Requests for severe accident investigations and assurance of mitigation measures have increased for operating nuclear power plants and the design of advanced nuclear power plants. Severe accident analysis investigations necessitate the analysis of the very complex physical phenomena that occur sequentially during various stages of accident progression. Computer codes are essential tools for understanding how the reactor and its containment might respond under severe accident conditions. The IAEA organizes coordinated research projects (CRPs) to facilitate technology development through international collaboration among Member States. The CRP on Benchmarking Severe Accident Computer Codes for HWR Applications was planned on the advice and with the support of the IAEA Nuclear Energy Department's Technical Working Group on Advanced Technologies for HWRs (the TWG-HWR). This publication summarizes the results from the CRP participants. The CRP promoted international collaboration among Member States to improve the phenomenological understanding of severe core damage accidents and the capability to analyse them. The CRP scope included the identification and selection of a severe accident sequence, selection of appropriate geometrical and boundary conditions, conduct of benchmark analyses, comparison of the results of all code outputs, evaluation of the capabilities of computer codes to predict important severe accident phenomena, and the proposal of necessary code improvements and/or new experiments to reduce uncertainties. Seven institutes from five countries with HWRs participated in this CRP

  14. Antifoaming materials studies in G.S. (Girlder sulfide) heavy water plants. Chemical stability. Pt. 1

    International Nuclear Information System (INIS)

    As in Girlder sulfide (G.S.) heavy water plants the system is inherently foaming, it is necessary to use antifoaming materials to solve this problem. This work describes the assays and results of some surfactants that can be employed to this purpose, under the corresponding temperature and pressure conditions of the plant. (Author)

  15. Analysis of Removal Alternatives for the Heavy Water Components Test Reactor at the Savannah River Site

    International Nuclear Information System (INIS)

    This engineering study was developed to evaluate different options for decommissioning of the Heavy Water Components Test Reactor (HWCTR) at the Savannah River Site. This document will be placed in the DOE-SRS Area reading rooms for a period of 30 days in order to obtain public input to plans for the demolition of HWCTR

  16. Health physics problems due to tritium around heavy-water reactors

    International Nuclear Information System (INIS)

    A review is made, after one year operation, of the protection against tritium in a heavy-water reactor: - nature of the tritium risk, particular to this type of installation; - detection and measurement equipment; - working method; - results obtained concerning the supervision of the personnel, the installation, and the servicing operations. (authors)

  17. Calculations on heavy-water moderated and cooled natural uranium fuelled power reactors

    International Nuclear Information System (INIS)

    One of the codes that the Instituto Nacional de Investigaciones Nucleares (Mexico) has for the nuclear reactors design calculations is the LEOPARD code. This work studies the reliability of this code in reactors design calculations which component materials are the same of the heavy water moderated and cooled, natural uranium fuelled power reactors. (author)

  18. Measures to diminish leaching of heavy metals to surface waters from agricultural soils

    NARCIS (Netherlands)

    Schipper, P.N.M.; Bonten, L.T.C.; Plette, A.C.C.; Moolenaar, S.W.

    2008-01-01

    Historical accumulation of heavy metals in agricultural soils has caused an increased leaching to shallow groundwater in the Netherlands. The elevated concentrations of metals like copper and zinc in shallow groundwater, causes problems to meet target levels in surface waters. Important sources for

  19. Preparation and validation of gas sealed high isotopic purity heavy water reference standards

    International Nuclear Information System (INIS)

    The method for preparation of helium gas sealed high isotopic purity heavy water (D2O) reference standards on a large scale has been amply demonstrated. The percentage purity of the reference standards has been estimated employing Fourier-Transform Infrared (FT-IR) method standardized with certified D2O standard and confirmed by validation using the same method with supplementary certified standard having its purity value declared from a different method – Fourier-Transform Nuclear Magnetic Resonance (FT-NMR) spectroscopy, each of the certified standards having an accuracy of + 0.01 wt.%. The work has also been extended in the preparation of high purity reference standards (99.86 wt.%, 99.90 wt.% and 99.96 wt.%) with an accuracy of + 0.01 wt.% in stainless steel storage-containers (total 15 Nos.) in collaboration with Heavy Water Plant (HWP) laboratory, Baroda, Vadodara. The standards prepared are extremely useful for day-to-day quality control of product D2O as well as certifying the quality of export consignments from different HWPs. This also helps all the heavy water plant laboratories in India to analyze high grade heavy water samples with same level of accuracy and reproducibility. (author)

  20. Study of thermal neutron currents near cylindrical absorbers located in heavy water

    International Nuclear Information System (INIS)

    The experiments reported involved determining the angular response of detectors to neutrons exterior to the surface of long cylindrical absorbers immersed in a scattering medium. The absorbers consisted of solid cylinders of copper, cadmium, or natural uranium in a fuel lattice, and combinations of copper and cadmium, as well as voided cylinders. The scattering (moderating) medium consisted of heavy water. (author)

  1. Analysis of Removal Alternatives for the Heavy Water Components Test Reactor at the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Owen, M.B. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1996-08-01

    This engineering study was developed to evaluate different options for decommissioning of the Heavy Water Components Test Reactor (HWCTR) at the Savannah River Site. This document will be placed in the DOE-SRS Area reading rooms for a period of 30 days in order to obtain public input to plans for the demolition of HWCTR.

  2. Graphite-moderated and heavy water-moderated spectral shift controlled reactors

    International Nuclear Information System (INIS)

    It has been studied the physical mechanisms related with the spectral shift control method and their general positive effects on economical and non-proliferant aspects (extension of the fuel cycle length and low proliferation index). This methods has been extended to non-hydrogenous fuel cells of high moderator/fuel ratio: heavy water cells have been con- trolled by graphite rods graphite-moderated and gas-cooled cells have been controlled by berylium rods and graphite-moderated and water-cooled cells have been controlled by a changing mixture of heavy and light water. It has been carried out neutron and thermal analysis on a pre design of these types of fuel cells. We have studied its neutron optimization and their fuel cycles, temperature coefficients and proliferation indices. Finally, we have carried out a comparative analysis of the fuel cycles of conventionally controlled PWRs and graphite-moderated, water-cooled and spectral shift controlled reactors. (Author) 71 refs

  3. Advances in numerical simulation of nonlinear water waves

    CERN Document Server

    Ma, Qingwei

    2014-01-01

    Most of the Earth's surface is covered by water. Our everyday lives and activities are affected by water waves in oceans, such as the tsunami that occurred in the Indian Ocean on 26 December 2004. This indicates how important it is for us to fully understand water waves, in particular the very large ones. One way to do so is to perform numerical simulation based on the nonlinear theory. Considerable research advances have been made in this area over the past decade by developing various numerical methods and applying them to emerging problems; however, until now there has been no comprehensive

  4. An advanced CANDU reactor with supercritical water coolant: conceptual design features

    International Nuclear Information System (INIS)

    AECL is studying an advanced CANDU reactor concept, with supercritical steam as coolant. The coolant, being a high density gas, at a pressure above 22 MPa and temperatures above 370 deg C, does not encounter the two-phase region with its associated fuel-dryout and flow-instability problems. Increased coolant temperature leads directly to increased plant thermodynamic efficiency, thereby reducing unit energy cost through reduced specific capital cost and reduced fueling cost. The reduced coolant in-core density leads to sufficiently reduced void reactivity, so that light water becomes a coolant option. The use of supercritical water coolant also opens up the possibility of enhanced safety with a natural circulation primary flow, taking advantage of the gas expansion coefficient. To preserve neutron economy, especially at high coolant temperatures, a fuel channel that is currently being developed has a pressure tube that is thermally insulated from high-temperature coolant and is in contact with the cold heavy-water moderator. Two stages of development of a supercritical-cooled CANDU reactor were identified. The first uses conventional or near-conventional zirconium-alloy fuel cladding with coolant core-mean temperatures near 400 deg C, and the second uses advanced high-temperature fuel cladding at coolant core-mean temperatures near 500 deg C. A first-stage cost reduction of 20% from the CANDU 6 design is estimated as a result of improved thermodynamic efficiency. A large change in coolant density across the core leads to a factor 3 or 4 reduction in heavy-water inventory and a corresponding reduction in coolant void reactivity. The latter leads to improved fuel burnup and reduced demands on the safety shutdown systems. (author)

  5. 重水的氢同位素组成分析%Hydrogen Isotope Analysis of Heavy Water

    Institute of Scientific and Technical Information of China (English)

    李立武; 杜晓宁

    2005-01-01

    Hydrogen gas was prepared from heavy water by using the H/Device, which was based on reduction with hot chromium. The H/Device was connected to a mass spectrometer. The hydrogen isotopic composition of heavy water was analyzed. It is shown that hydrogen isotopic composition can be analyzed conveniently, little sample is used and the results are reliable.

  6. Waste minimization through process optimization/integration and resource management at eco-friendly Heavy Water Plants

    International Nuclear Information System (INIS)

    Heavy Water Board has celebrated 2003 as Environmental Conservation Year captivating a range of enviro-friendly measures. This article attempts to give a brief overview of the outcome of systems and adapted procedures for waste minimization through process integration and resource management at Heavy Water Plants

  7. Heavy metal concentration in fish tissues inhabiting waters of "Busko Blato" reservoir (Bosnia and Herzegovina).

    Science.gov (United States)

    Has-Schön, Elizabeta; Bogut, Ivan; Kralik, Gordana; Bogut, Stjepan; Horvatić, Janja; Cacić, Milan; Cacić, Ivan

    2008-09-01

    Heavy metals concentration (mercury, lead, cadmium, arsenic, copper, zinc and chromium) in tissues (muscles, liver, kidney and gonads) of Dalmatian barbelgudgeon, the nase, the souffie and brown trout, inhabiting waters of Busko Blato reservoir in Bosnia and Herzegovina, has been determined by atomic absorption spectrophotometry. The meat of the tested fish sorts does not contain elevated concentration of most analyzed heavy metals with exception of lead (higher than MAC in Italy, Germany and Denmark) and mercury (in muscles of brown trout higher than MAC in most countries). The lowest level of all heavy metals is always detected in gonads, with higher values in fry compared to milt for copper, zinc, chromium and arsenic. The highest copper concentration is observed in the liver from the souffie which is suggested as a suitable biomonitor for copper intoxication. In muscles of all fish sorts, lead was always present in much higher concentration than cadmium, while in kidneys of most fish sorts, lead and cadmium concentrations were similar. We showed that bioaccumulation of some heavy metals in the fish sorts analyzed is tissue and sex dependent. Also, we concluded that the small water exchange in reversible shallow reservoir does not induce elevated concentration of heavy metals in fish tissues inhabiting Busko Blato. PMID:17342437

  8. Neutronic calculations in heavy water moderated multiplying media using GGC-3 library nuclear data

    International Nuclear Information System (INIS)

    Differences in obtaining transference matrices between GGC-3 code and the system to produce multigroup cross sections using GGC-3 library, recently implemented at the Neutrons and Reactors Division, have been analized. Neutronic calculations in multiplicative systems containing heavy water have been made using both methods. From the obtained results, it is concluded that the new method is more appropriate to deal with systems including moderators other than light water. (author)

  9. Ultra deep water minimum production riser system for heavy fluid

    Energy Technology Data Exchange (ETDEWEB)

    Saint-Marcoux, Jean-Francois; Wu, Mason [Acergy M.S. Ltd., London (United Kingdom)

    2008-07-01

    Understanding the intricacies of a reservoir is a lengthy process. Deep water reservoirs are often compartmented. The access to the various areas of production requires drilling from several locations. As each of these zones is being brought to production, additional riser facilities are required. Therefore, the concept of a standardized minimum production riser system that is capable of being installed phase after phase is appealing. The minimum functions required for oil production are two-looped production lines, and one or two injection lines, fitting with a riser system dedicated to an isolated oil field. Such a concept is presented in this paper. Acergy has designed, built and installed the large bundled Hybrid Riser Towers of Girassol and Greater Plutonio, and has further streamlined its design and construction methods. Such project requires not only the capacity to engineer the facilities but also to source the material, manage the fabrication in country and execute the complex operations. This requires project management capacities to be able to ensure consistent interfaces, maintain schedule and budget accordingly. The proposed ultra deep water Minimum Production System incorporates lessons learned from all aspects of the Greater Plutonio and Girassol projects to further enhance the ability to handle a wide range of water depths and well fluids (from low to high GOR), including elevated pressure and temperature. The proposed Minimum Production Hybrid Riser Tower (MPHRT) lends itself to be decommissioned and reused if cost-efficient for the field development. (author)

  10. INCREASING HEAVY OIL RESERVES IN THE WILMINGTON OIL FIELD THROUGH ADVANCED RESERVOIR CHARACTERIZATION AND THERMAL PRODUCTION TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2001-08-08

    The objective of this project is to increase the recoverable heavy oil reserves within sections of the Wilmington Oil Field, near Long Beach, California, through the testing and application of advanced reservoir characterization and thermal production technologies. The hope is that successful application of these technologies will result in their implementation throughout the Wilmington Field and, through technology transfer, will be extended to increase the recoverable oil reserves in other slope and basin clastic (SBC) reservoirs. The existing steamflood in the Tar zone of Fault Block II-A (Tar II-A) has been relatively inefficient because of several producibility problems which are common in SBC reservoirs: inadequate characterization of the heterogeneous turbidite sands, high permeability thief zones, low gravity oil and non-uniform distribution of the remaining oil. This has resulted in poor sweep efficiency, high steam-oil ratios, and early steam breakthrough. Operational problems related to steam breakthrough, high reservoir pressure, and unconsolidated sands have caused premature well and downhole equipment failures. In aggregate, these reservoir and operational constraints have resulted in increased operating costs and decreased recoverable reserves. A suite of advanced reservoir characterization and thermal production technologies are being applied during the project to improve oil recovery and reduce operating costs, including: (1) Development of three-dimensional (3-D) deterministic and stochastic reservoir simulation models--thermal or otherwise--to aid in reservoir management of the steamflood and post-steamflood phases and subsequent development work. (2) Development of computerized 3-D visualizations of the geologic and reservoir simulation models to aid reservoir surveillance and operations. (3) Perform detailed studies of the geochemical interactions between the steam and the formation rock and fluids. (4) Testing and proposed application of a

  11. Impact of high energy heavy ion nuclear collisions on advancement of nuclear physics

    International Nuclear Information System (INIS)

    The contributions of low energy heavy ion research to the inventions in nuclear physics are highlighted. The theoretical ideas used in their interpretations are qualitatively discussed. The survey of the literature relevant to charged particle spectroscopy and reactions with heavy ions is presented. The light projectile collision work and its relevant physics is also briefly summarized. In light of this, few suggestions are made to effectively use our heavy ion facilities. (author). 4 refs

  12. Heavy Metal Concentration in Drinking Water Sources Affected by Dredge Mine Operations of a Gold Mining Company in Ghana

    OpenAIRE

    Apori Ntiforo; Maxwell Anim-Gyampo; Frank K. Nyame

    2012-01-01

    The study assesses concentration of certain heavy metals in water sources affected by the operations of defunct dredged gold mine operations more than a decade to evaluate its quality as a source of drinking water. The concentration of heavy metals were determined from nine (9) surface water sampling points and three (3) boreholes in the Awusu-River basin in comparison with their maximum contaminant levels to assess their suitability as drinking water sources. Results obtained from the analys...

  13. Increasing Heavy Oil Reserves in the Wilmington Oil Field Through Advanced Reservoir Characterization and Thermal Production Technologies, Class III

    Energy Technology Data Exchange (ETDEWEB)

    City of Long Beach; Tidelands Oil Production Company; University of Southern California; David K. Davies and Associates

    2002-09-30

    The objective of this project was to increase the recoverable heavy oil reserves within sections of the Wilmington Oil Field, near Long Beach, California through the testing and application of advanced reservoir characterization and thermal production technologies. The successful application of these technologies would result in expanding their implementation throughout the Wilmington Field and, through technology transfer, to other slope and basin clastic (SBC) reservoirs.

  14. Increasing Heavy Oil Reserves in the Wilmington Oil Field Through Advanced Reservoir Characterization and Thermal Production Technologies, Class III

    Energy Technology Data Exchange (ETDEWEB)

    City of Long Beach; Tidelands Oil Production Company; University of Southern California; David K. Davies and Associates

    2002-09-30

    The objective of this project was to increase the recoverable heavy oil reserves within sections of the Wilmington Oil Field, near Long Beach, California through the testing and application of advanced reservoir characterization and thermal production technologies. It was hoped that the successful application of these technologies would result in their implementation throughout the Wilmington Field and, through technology transfer, will be extended to increase the recoverable oil reserves in other slope and basin clastic (SBC) reservoirs.

  15. BIOSORPTION AND RECOVERY OF HEAVY METALS FROM AQUEOUS SOLUTIONS BY EICHHORNIA CRASSIPES (WATER HYACINTH) ASH

    OpenAIRE

    Tariq Mahmood; Salman Akbar Malik; Syed Tajammul Hussain

    2010-01-01

    Heavy metal’s release without treatment poses a significant threat to the environment. Heavy metals are non-biodegradable and persistent. In the present study the ash of water hyacinth (Eichhornia crassipes), was used to remove six metals from aqueous solutions through biosorption. Results of batch and column experiments showed excellent adsorption capacity. Removal of lead, chromium, zinc, cadmium, copper, and nickel was 29.83, 1.263, 1.575, 3.323, 2.984 and 1.978 µgg-1, respectively. The bi...

  16. Problems of hydrogen - water vapor - inert gas mixture use in heavy liquid metal coolant technology

    International Nuclear Information System (INIS)

    The reasons of slag deposit formation in circulation circuits with heavy liquid metal coolants, which can cause reactor core blockage, are considered. To prevent formation of deposits hydrogen purification of coolant and surfaces of circulation circuit is used. It consists in introduction of gaseous mixtures hydrogen - water vapor - rare gas (argon or helium) directly into coolant flow. The principle scheme of hydrogen purification and the processes occurring during it are under consideration. Measures which make it completely impossible to overlap of the flow cross section of reactor core, steam generators, pumps and other equipment by lead oxides in reactor facilities with heavy liquid metal coolants are listed

  17. Modeling Adsorption Kinetics (Bio-remediation of Heavy Metal Contaminated Water)

    Science.gov (United States)

    McCarthy, Chris

    My talk will focus on modeling the kinetics of the adsorption and filtering process using differential equations, stochastic methods, and recursive functions. The models have been developed in support of our interdisciplinary lab group which is conducting research into bio-remediation of heavy metal contaminated water via filtration through biomass such as spent tea leaves. The spent tea leaves are available in large quantities as a result of the industrial production of tea beverages. The heavy metals bond with the surfaces of the tea leaves (adsorption). Funding: CUNY Collaborative Incentive Research Grant.

  18. Quantitative analysis of water heavy by NMR spectroscopy

    International Nuclear Information System (INIS)

    Nuclear Magnetic Resonance has been applied to a wide variety of quantitative problems. A typical example has been the determination of isotopic composition. In this paper two different analytical methods for the determination of water in deuterium oxide are described. The first one, employs acetonitril as an internal standard compound and in the second one calibration curve of signal integral curve versus amount of D2O is constructed. Both methods give results comparable to those of mass spectrometry of IR spectroscopy. (Author) 5 refs

  19. Responses to Oxidative and Heavy Metal Stresses in Cyanobacteria: Recent Advances

    Directory of Open Access Journals (Sweden)

    Corinne Cassier-Chauvat

    2014-12-01

    Full Text Available Cyanobacteria, the only known prokaryotes that perform oxygen-evolving photosynthesis, are receiving strong attention in basic and applied research. In using solar energy, water, CO2 and mineral salts to produce a large amount of biomass for the food chain, cyanobacteria constitute the first biological barrier against the entry of toxics into the food chain. In addition, cyanobacteria have the potential for the solar-driven carbon-neutral production of biofuels. However, cyanobacteria are often challenged by toxic reactive oxygen species generated under intense illumination, i.e., when their production of photosynthetic electrons exceeds what they need for the assimilation of inorganic nutrients. Furthermore, in requiring high amounts of various metals for growth, cyanobacteria are also frequently affected by drastic changes in metal availabilities. They are often challenged by heavy metals, which are increasingly spread out in the environment through human activities, and constitute persistent pollutants because they cannot be degraded. Consequently, it is important to analyze the protection against oxidative and metal stresses in cyanobacteria because these ancient organisms have developed most of these processes, a large number of which have been conserved during evolution. This review summarizes what is known regarding these mechanisms, emphasizing on their crosstalk.

  20. Graphene-Based Microbots for Toxic Heavy Metal Removal and Recovery from Water.

    Science.gov (United States)

    Vilela, Diana; Parmar, Jemish; Zeng, Yongfei; Zhao, Yanli; Sánchez, Samuel

    2016-04-13

    Heavy metal contamination in water is a serious risk to the public health and other life forms on earth. Current research in nanotechnology is developing new nanosystems and nanomaterials for the fast and efficient removal of pollutants and heavy metals from water. Here, we report graphene oxide-based microbots (GOx-microbots) as active self-propelled systems for the capture, transfer, and removal of a heavy metal (i.e., lead) and its subsequent recovery for recycling purposes. Microbots' structure consists of nanosized multilayers of graphene oxide, nickel, and platinum, providing different functionalities. The outer layer of graphene oxide captures lead on the surface, and the inner layer of platinum functions as the engine decomposing hydrogen peroxide fuel for self-propulsion, while the middle layer of nickel enables external magnetic control of the microbots. Mobile GOx-microbots remove lead 10 times more efficiently than nonmotile GOx-microbots, cleaning water from 1000 ppb down to below 50 ppb in 60 min. Furthermore, after chemical detachment of lead from the surface of GOx-microbots, the microbots can be reused. Finally, we demonstrate the magnetic control of the GOx-microbots inside a microfluidic system as a proof-of-concept for automatic microbots-based system to remove and recover heavy metals. PMID:26998896

  1. Evaluation of heavy water for indicator dilution cardiac output measurement

    Energy Technology Data Exchange (ETDEWEB)

    Schreiner, M.S.; Leksell, L.G.; Neufeld, G.R. (Univ. of Pennsylvania School of Medicine, Philadelphia (USA))

    1989-10-01

    We evaluated deuterium oxide (D2O) as a tracer for cardiac output measurements. Cardiac output measurements made by thermodilution were compared with those made by indicator dilution with D2O and indocyanine green as tracers. Five triplicate measurements for each method were made at intervals of 30 minutes in each of 9 anesthetized, mechanically ventilated goats. Cardiac output ranged between 0.68 and 3.79 L/min. The 45 data points yielded a correlation coefficient of 0.948 for the comparison of D2O indicator dilution cardiac output measurements with thermodilution measurements and a linear regression slope of 1.046. D2O indicator dilution measurements were biased by -0.11 +/- 0.22 L/min compared with thermodilution measurements and had a standard deviation of +/- 0.12 L/min for triplicate measurements. Hematocrits ranging between 20 and 50 vol% had no effect on optical density for D2O. D2O is more stable than indocyanine green and approximately one-tenth the price (40 cents per injection compared with $4). The basic instrumentation cost of approximately $9,000 is an additional initial expense, but provides the ability to perform pulmonary extravascular water measurements with a double-indicator dilution technique. D2O has potential as a tracer for the clinical determination of indicator dilution cardiac output measurements and pulmonary extravascular water measurements.

  2. Prolong Restoration of the Water Quality of River Ganga Effect of Heavy Metals and Radioactive Elements.

    Science.gov (United States)

    Tare, Vinod; Basu, Subhankar

    2014-04-01

    The genesis of the present research was the belief since ages and the observations made through some studies that the water of river Ganga has unique characteristics, which allows storage of water quality even on prolong storage. Very few systematic studies have been conducted to support the contention that the Ganga water indeed has some special composition that could be attributed to its unique storage capacity. It was postulated that prolong restoration of water quality depends on the ability to arrest microbial activity that is generally responsible for deterioration in water quality on prolong storage. Hence, attempt has been made to identify the parameters that are likely to influence the prolong storage of river water. Along with Ganga river water, other three major rivers, viz. Yamuna, Godavari and Narmada, were selected for comparison. Emphasis was made on estimation of heavy metals, radioactive elements, dissolved carbon and other physicochemical parameters such as temperature, pH, alkalinity, hardness and dissolved organic carbon. Based on the available information regarding the impact of heavy metals, radioactive elements vis-à-vis the chemical composition of water on microorganisms in the aquatic environment, an overall impact score for the waters of the four Indian rivers selected in the study has been assigned. PMID:26563059

  3. Natural Circulation Phenomena and Modelling for Advanced Water Cooled Reactors

    International Nuclear Information System (INIS)

    The role of natural circulation in advanced water cooled reactor design has been extended with the adoption of passive safety systems. Some designs utilize natural circulation to remove core heat during normal operation. Most passive safety systems used in evolutionary and innovative water cooled reactor designs are driven by natural circulation. The use of passive systems based on natural circulation can eliminate the costs associated with the installation, maintenance and operation of active systems that require multiple pumps with independent and redundant electric power supplies. However, considering the weak driving forces of passive systems based on natural circulation, careful design and analysis methods must be employed to ensure that the systems perform their intended functions. Several IAEA Member States with advanced reactor development programmes are actively conducting investigations of natural circulation to support the development of advanced water cooled reactor designs with passive safety systems. To foster international collaboration on the enabling technology of passive systems that utilize natural circulation, in 2004 the IAEA initiated a coordinated research project (CRP) on Natural Circulation Phenomena, Modelling and Reliability of Passive Systems that Utilize Natural Circulation. Three reports were published within the framework of this CRP. The first report (IAEA-TECDOC-1474) contains the material developed for the first IAEA training course on natural circulation in water cooled nuclear power plants. The second report (IAEA-TECDOC-1624) describes passive safety systems in a wide range of advanced water cooled nuclear power plant designs, with the goal of gaining insights into system design, operation and reliability. This third, and last, report summarizes the research studies completed by participating institutes during the CRP period.

  4. Heavy water reactors: Status and projected development. Part I. Final draft of a report to be published in the IAEA technical reports series. Working material

    International Nuclear Information System (INIS)

    In 1996, the 40th General Conference of the IAEA approved the establishment of a new International Working Group (IWG) on Advanced Technologies for Heavy Water Reactors (HWR). At its first meeting, held in June 1997, the IWG-HWR advised the Agency to prepare a TECDOC to present: a) the status of HWR advanced technology in the areas of economics, safety and fuel cycle flexibility and sustainable development; and b) the advanced technology developments needed in the following two decades to achieve the vision of the advanced HWR. The IAEA convened two consultancies and two Advisory Group Meetings to prepare the TECDOC. One of the consultancies was on 'Fuel Cycle Flexibility and Sustainable Development'; the second was on 'Passive Safety Features of HWRs Status and Projected Advances'. The members of the IWG-HWR collectively agreed on the essential features that the development of HWRs must emphasize. These 'drivers' are: improved economics: the fundamental requirement for all successful high technology developments to advance, is real economic improvements, consistent with improved quality; enhanced safety: to meet increasingly stringent requirements to satisfy the regulatory authorities, the public and the operators, an evolutionary safety path will be followed, incorporating advanced passive safety concepts where it is feasible and sensible to do so; sustainable development: the high neutron economy of HWRs results in a reactor that can burn natural uranium at high utilization, utilize spent fuel from other reactor types, and, through various recycle strategies including use of thorium, extend fissile fuel resources into the indefinite future. The objectives of this document are: to present the status of HWR technology; to document the safety characteristics of current HWR designs and the potential enhancements; to present a 'vision' of the long-term development of the HWR for use into the next century as an electricity source that is sustainable and flexible and

  5. Heavy water reactors: Status and projected development. Part II. Final draft of a report to be published in the IAEA technical reports series. Working material

    International Nuclear Information System (INIS)

    In 1996, the 40th General Conference of the IAEA approved the establishment of a new International Working Group (IWG) on Advanced Technologies for Heavy Water Reactors (HWR). At its first meeting, held in June 1997, the IWG-HWR advised the Agency to prepare a TECDOC to present: a) the status of HWR advanced technology in the areas of economics, safety and fuel cycle flexibility and sustainable development; and b) the advanced technology developments needed in the following two decades to achieve the vision of the advanced HWR. The IAEA convened two consultancies and two Advisory Group Meetings to prepare the TECDOC. One of the consultancies was on 'Fuel Cycle Flexibility and Sustainable Development'; the second was on 'Passive Safety Features of HWRs Status and Projected Advances'. The members of the IWG-HWR collectively agreed on the essential features that the development of HWRs must emphasize. These 'drivers' are: improved economics: the fundamental requirement for all successful high technology developments to advance, is real economic improvements, consistent with improved quality; enhanced safety: to meet increasingly stringent requirements to satisfy the regulatory authorities, the public and the operators, an evolutionary safety path will be followed, incorporating advanced passive safety concepts where it is feasible and sensible to do so; sustainable development: the high neutron economy of HWRs results in a reactor that can burn natural uranium at high utilization, utilize spent fuel from other reactor types, and, through various recycle strategies including use of thorium, extend fissile fuel resources into the indefinite future. The objectives of this document are: to present the status of HWR technology; to document the safety characteristics of current HWR designs and the potential enhancements; to present a 'vision' of the long-term development of the HWR for use into the next century as an electricity source that is sustainable and flexible and

  6. Water chemistry control to meet the advanced design and operation of light water reactors

    International Nuclear Information System (INIS)

    Water chemistry control is one of the key technologies to establish safe and reliable operation of nuclear power plants. The road maps on R and D plans for water chemistry of nuclear power systems in Japan have been proposed along with promotion of R and D related water chemistry improvement for the advanced application of light water reactors (LWRs). The technical trends were divided into four categories, dose rate reduction, structural integrity, fuel integrity and radioactive waste reduction, and latest technical break through for each category was shown for the advanced application of LWRs. At the same time, the technical break through and the latest movements for regulation of water chemistry were introduced for each of major organizations related to nuclear engineering in the world. The conclusions were summarized as follows; 1. Water chemistry improvements might contribute to achieve the advanced application of LWRs, while water chemistry should be often changed to achieve the advanced application of LWRs. 2. Only one solution for water chemistry control was not obtained for achieving the advanced application of LWRs, but miscellaneous solutions were possible for achieving one. Optimal water chemistry control was desired for having the good practices for satisfying multi-targets at the same time and it was much affected by the plant unique systems and operational history. 3. That meant it was difficult to determine water chemistry regulation targets for achieving application of LWRs but it was necessary to prepare suitable guideline for good achievement of application of LWRs. That meant the guideline should be recommendation for good practice in the plant. 4. The water chemistry guide line should be modified along with progress of plant operation and water chemistry and related technologies. (author)

  7. Chemical elimination of alumina in suspension in nuclear reactors heavy water

    International Nuclear Information System (INIS)

    Corrosion of aluminium in contact with moderating water in nuclear reactor leads to the formation of an alumina hydrosol which can have an adverse effect on the operation of the reactor. Several physical methods have been used in an attempt to counteract this effect. The method proposed here consists in the elimination of the aluminium by dissolution and subsequent fixation in the ionic form on mixed-bed ion-exchange resin. In order to do this, the parameters and the values of these parameters most favorable to the dissolution process have been determined. If the moderator is heavy water, the deuterated acid can be prepared by converting a solution in heavy water to a salt of the acid using a deuterated cationic resin. (author)

  8. Safety and environmental aspects of heavy water production (Paper No. 4.1)

    International Nuclear Information System (INIS)

    Different processes are utilised for heavy water production in the heavy water plants in India. H2S is used in large quantities as carrier gas to extract deuterium content from water. The safe handling of such large quantities of H2S gas poses a major problem because of its toxicity, high corrosive nature and high flammability. Handling of large quantities of synthesis gas in ammonia based plants at high pressure and temperature poses a major problem because it is a mixture of hydrogen and nitrogen. H2 is highly inflammable and explosive when mixed with air or oxygen. All the safety aspects considered while designing, fabricating, constructing and operating the plants are described. (author). 5 tabs

  9. Uses of Plutonium Fuel in Pressure-Tube-Type, Heavy-Water-Moderated Thermal Reactors

    International Nuclear Information System (INIS)

    In 1962, a feasibility study was begun in the JAERI on the uses of various nuclear fuels for pressure-tube-type, heavy-water-moderated thermal reactors. This study began with analysis of the use of uranium in heavy-water-moderated thermal reactors such as the CANDU-PHW, CANDU-BLW, SGHW, EL-4, and Ref. 15, D and E lattices, which is designed in the JAERI, from the standpoint of the core design. Then, the ways of using plutonium fuel in the same types were investigated using WATCHTOWER, FLARE and VENUS codes, including: (1) direct substitution of the plutonium from light-water reactors or Magnox reactors, (2) recycle use of the plutonium from heavy-water-moderated reactors, (3) plutonium self-sustaining cycle, and (4) plutonium phoenix fuel. The following conclusions are reported: (1) In the direct substitution of plutonium, somewhat depleted plutonium is more suitable for core design than the plutonium from Magnox reactors or light-water reactors, because the increase in the initial reactivity due to large plutonium absorption cross-section must be prevented. (2) In the plutonium self-sustaining cycle, the fuel burn-up of about 15 000 ∼20000 MWd/t would be expected from natural uranium, and the positive void reactivity which always occurs in the uraniumloaded SGHW or CANDU-BLW lattices is greatly reduced, the latter property giving some margin to bum-out heat flux. (3) It may be concluded from the fuel cycle analysis that the plutonium self-sustaining cycle is equivalent to using slightly enriched uranium (about 1.0 at.%). It may be concluded that the use of plutonium in heavy-water-moderated reactors is technologically feasible and economically advantageous. (author)

  10. Status of advanced light water reactor designs 2004

    International Nuclear Information System (INIS)

    The report is intended to be a source of reference information for interested organizations and individuals. Among them are decision makers of countries considering implementation of nuclear power programmes. Further, the report is addressed to government officials with an appropriate technical background and to research institutes of countries with existing nuclear programmes that wish to be informed on the global status in order to plan their nuclear power programmes including both research and development efforts and means for meeting future. The future utilization of nuclear power worldwide depends primarily on the ability of the nuclear community to further improve the economic competitiveness of nuclear power plants while meeting stringent safety requirements. The IAEA's activities in nuclear power technology development include the preparation of status reports on advanced reactor designs to provide all interested IAEA Member States with balanced and objective information on advances in nuclear plant technology. In the field of light water reactors, the last status report published by the IAEA was 'Status of Advanced Light Water Cooled Reactor Designs: 1996' (IAEA-TECDOC-968). Since its publication, quite a lot has happened: some designs have been taken into commercial operation, others have achieved significant steps toward becoming commercial products, including certification from regulatory authorities, some are in a design optimization phase to reduce capital costs, development for other designs began after 1996, and a few designs are no longer pursued by their promoters. With this general progress in mind, on the advice and with the support of the IAEA Department of Nuclear Energy's Technical Working Group on Advanced Technologies for Light Water Reactors (LWRs), the IAEA has prepared this new status report on advanced LWR designs that updates IAEA-TECDOC-968, presenting the various advanced LWR designs in a balanced way according to a common outline

  11. Qualification issues for advanced light-water reactor protection systems

    International Nuclear Information System (INIS)

    The instrumentation and control (I ampersand C) systems in advanced reactors will make extensive use of digital controls, microprocessors, multiplexing, and fiber optic transmission. Elements of these advances in I ampersand C have been implemented on some current operating plants. However, the widespread use of the above technologies, as well as the use of artificial intelligence with minimum reliance on human operator control of reactors, highlights the need to develop standards for qualifying the I ampersand C used in the next generation of nuclear power plants. As a first step in this direction, the protection system I ampersand C for present-day plants was compared to that proposed for advanced light-water reactors (ALWRs). An evaluation template was developed by assembling a configuration of a safety channel instrument string for a generic ALWR, then comparing the impact of environmental stressors on that string to their effect on an equivalent instrument string from an existing light-water reactor. The template was then used to suggest a methodology for the qualification of microprocessor-based protection systems. The methodology identifies standards/regulatory guides (or lack thereof) for the qualification of microprocessor-based safety I ampersand C systems. This approach addresses in part issues raised in NRC policy document SECY-91-292, which recognizes that advanced I ampersand C systems for the nuclear industry are ''being developed without consensus standards. as the technology available for design is ahead of the technology that is well understood through experience and supported by application standards.''

  12. Advances in Membrane Distillation for Water Desalination and Purification Applications

    Directory of Open Access Journals (Sweden)

    Juan Gomez

    2013-01-01

    Full Text Available Membrane distillation is a process that utilizes differences in vapor pressure to permeate water through a macro-porous membrane and reject other non-volatile constituents present in the influent water. This review considers the fundamental heat and mass transfer processes in membrane distillation, recent advances in membrane technology, module configurations, and the applications and economics of membrane distillation, and identifies areas that may lead to technological improvements in membrane distillation as well as the application characteristics required for commercial deployment.

  13. Economics of advanced light water reactors - Recent update

    International Nuclear Information System (INIS)

    This paper includes recently updated analyses of the economic prospects of advanced light water reactors (ALWRs) during the decade of the 1990s. United Engineers and Constructors (UE and C) has performed engineering economic analyses related to ALWRs over the last 5 yr using both target economics and detailed cost-estimating methodologies. It has been found through such cost comparisons that properly designed and constructed ALWRs should cost less than the target cost figures listed above and significantly less than the pressurized water reactor better experience reference LWR plant cost

  14. New variants of the separation of heavy metals from waste water

    International Nuclear Information System (INIS)

    Usual procedures of the metal ion separation from waste water are: - Neutralisation and precipitation - precipitation of sulphide or sulphide-derivatives - ion exchange - membrane filtration, partly after complexation for molecular enlargement - adsorption at biomass and at inorganic adsorbents - electrolysis. The hydroxide precipitation is the indispensable first step of the metal ion separation. The precipitation with toxic sulphides and sulphide derives hazardous compounds and should be replaced by suitable procedures with non-toxic substances. An example of heavy metal ion elimination from waters with specific working precipitants is the separation of uranium from seeping and flooding waters of the former uranium ore mining industry in the Saxonian Erzgebirge. (orig.)

  15. HEAVY METAL CONTAMINATIONS IN SAGAR LAKE AND DRINKING WATER SOURCES OF SAGAR CITY

    OpenAIRE

    Nahid Parveen; Y. Rohan

    2012-01-01

    There are various toxic elements present in our surroundings out of that the toxic heavy metals Pb,Cd, As, Se, Cr and Cu can cause several harms to human these metals enter in humans by water. The all kind ofwaste materials are thrown into natural water bodies in each city, this makes the all ground and natural watersources contaminated. The all six metals have determined by Atomic absorption spectrophotometer(AAS) inselected water samples from Sagar Lake and dug wells, hand pumps, tube wells...

  16. Analytical performance of refractometry in quantitative estimation of isotopic concentration of heavy water in nuclear reactor

    International Nuclear Information System (INIS)

    The method of refractometry has been investigated for the quantitative estimation of isotopic concentration of D2O (heavy water) in a simulated water sample. Viability of Refractometry as an excellent analytical technique for rapid and non-invasive determination of D2O concentration in water samples has been demonstrated. Temperature of the samples was precisely controlled to eliminate effect of temperature fluctuation on refractive index measurement. Calibration performance by this technique exhibited reasonable analytical response over a wide range (1-100%) of D2O concentration. (author)

  17. Advanced technologies for water cooled reactors 1990. Pt. 1

    International Nuclear Information System (INIS)

    The meeting was attended by 20 participants from 12 countries who reviewed and discussed the status and progress of national programmes on advanced water-cooled reactors and recommended to the Scientific Secretary a comprehensive programme for 1991/1992 which would support technology development programmes in IWGATWR Member States. This summary report outlines the activities of IWGATWR since its Second Meeting in June 1988 and main results of the Third Meeting

  18. Advanced technologies for water cooled reactors 1990. Pt. 2

    International Nuclear Information System (INIS)

    The main purpose of the meeting was to review and discuss the status of national programmes, the progress achieved since the last meeting held in June 1988 in the field of advanced technologies and design trends for existing and future water cooled reactors. 24 specialists from 14 countries and the IAEA took part in the meeting and 12 papers were presented. A separate abstract was prepared for each of these papers. Refs, figs and tabs

  19. Monitoring of heavy/toxic metals and halides in surface/ground water (abstract)

    International Nuclear Information System (INIS)

    Water is essential for maintaining physical and social life. Human and animal consumption is perhaps the most evident essential use of water. Water quality and quantity have become critical issues, affecting all life. The importance of water in our lives, combined with the threats, make water resources use a global problem. Among the different pollutants toxic metals, metalloids and halides have special significance. Industrial effluents and municipal wastewater are normally drained into water streams, rivers and other reservoirs thus polluting these significantly. Quality of our water resources especially is an issue, which continues to arouse the attention of concerned scientists, legislators and the general public. Among various pollutant chemicals, the heavy metals and metalloids are present at trace levels in various compartments of the environment. Some metals become toxic even at trace levels because of the important features that distinguishes metals from other pollutants is that they are not biodegradable. The halides like Cl, Br, and I from different sources can enter easily into water systems and then they make their way directly into the human body. The intake of toxic as wells as essential elements through water and other food items like vegetables, milk wheat flour etc. is significant. The abundance or deficiency of these meals as well as halides results in abnormal metabolic functions. Due to excessive demand for trace analysis in water and other materials a variety of techniques and instrumentation has been developed. Determination of heavy metals ions is of the highest interest in environmental analysis. Among the food materials water is most important because of their large consumption by man. Also toxic metals in water may be in dissolved ionic form, which directly go into human metabolism and start their toxic action. Presence of even small amounts of toxic metals in drinking water can produce serious health hazards. (author)

  20. Neutronic challenges of advanced boiling water reactor designs

    International Nuclear Information System (INIS)

    The advancement of Boiling Water Reactor technology has been under investigation at the Center for Advance Nuclear Energy Systems at MIT. The advanced concepts under study provide economic incentives through enabling further power uprates (i.e. increasing vessel power density) or better fuel cycle uranium utilization. The challenges in modeling of three advanced concepts with focus on neutronics are presented. First, the Helical Cruciform Fuel rod has been used in some Russian reactors, and studied at MIT for uprating the power in LWRs through increased heat transfer area per unit core volume. The HCF design requires high fidelity 3D tools to assess its reactor physics behavior as well as thermal and fuel performance. Second, an advanced core design, the BWR-HD, was found to promise 65% higher power density over existing BWRs, while using current licensing tools and existing technology. Its larger assembly size requires stronger coupling between neutronics and thermal hydraulics compared to the current practice. Third is the reduced moderation BWRs, which had been proposed in Japan to enable breeding and burning of fuel as an alternative to sodium fast reactors. Such technology suffers from stronger sensitivity of its neutronics to the void fraction than the traditional BWRs, thus requiring exact modeling of the core conditions such as bypass voiding, to correctly characterize its performance. (author)

  1. Water flooding to displace heavy oil with electromagnetic resistive heating (ERH)

    Energy Technology Data Exchange (ETDEWEB)

    Oliverira, H.J.M.; Barillas, J.L.M.; Mata, W.; Dutra, T.V.Jr. [Federal Univ. of Rio Grande do Norte, Lagoa Nova (Brazil). Dept. of Petroleum Engineering

    2009-07-01

    The viscosity of heavy oil can be effectively reduced by increasing its temperature, thus providing better mobility in the reservoir. Steam flooding is a commonly used technique to improve oil recovery, but may not be technically possible or economically feasible in situations such as permafrost, deep formations, thin pay zones and low permeability formations. Therefore, alternative methods are needed to produce this heavy oil. This paper proposed the use of electromagnetic resistive heating (ERH), a thermal stimulation technique in which an electrical current passes through a formation to increase the original temperature by Joule effect. The reservoir temperatures increases proportionally as the electrical current intensity increases. This paper demonstrated the results of computational simulations using water injection, with or without ERH in a reservoir of heavy oil with similar characteristics to those found in northeastern Brazilian basins. The paper outlined the reservoir and fluids characteristics used to model the ERH process and waterflooding. It was concluded that using water flooding, without ERH to displace heavy oil can enhance oil recovery. 3 refs., 10 figs.

  2. Determination of naturally occurring radioactive materials, heavy metals and water quality at Bukit Rengit, Lanchang, Pahang

    International Nuclear Information System (INIS)

    Concentration of Natural Occurring Radioactive Materials, heavy metal and water Quality in salt lick must be preserved so that the salt lick is safe for use for wild animals. Sampling has been done in three different locations which are Location 1 known as Jenut Neram, Location 2 as Jenut Bayek and Location 3 as Jenut Girai. This study has been carried out to determine the natural radioactivity (238U, 232Th, 40K and 226Ra), heavy metal and to determine the water quality at Bukit Rengit, Lanchang, Pahang. Natural radioactivities were determined using Gamma Spectrometry System, the heavy metal determination was done using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and water quality was determined using the HACH method. For water quality, parameters that involved were temperature, pH, conductivity, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), nitrate, ammoniacal nitrogen (AN), solid suspended (SS) and turbidity. The average concentrations of natural radioactivities for the three different locations were 0.149 ± 0.052 Bq/ L for 238U, 0.063 ± 0.004 Bq/ L for 232Th, 0.030 ± 0.004 Bq/ L for 226Ra, and 0.528 ± 0.098 Bq/ L for 40K. 19 heavy metals have been found from the three different locations namely Al, As, Ba, Ca, Cd, Cr, Cu, Fe, Hg, Mg, Mn, Mo, Na, Ni, P, Pb,S, V, Zn. Na showed the highest concentration among the other heavy metal with ranging from 1976 ± 257 μg/ L - 4639 ± 85 μg/ L and Cd showed the lowest concentration ranging from 0 μg/ L -0.008 ± 0.006 μg/ L. Water Quality Index (WQI) and Interim National Water Quality Standard (INWQS) were used to classify the water quality of salt lick. The result showed that the salt lick water of Bukit Rengit, Lanchang are categorised under class III referred to WQI and INWQS. (author)

  3. A comparative study on determining tritium activity in heavy water samples

    International Nuclear Information System (INIS)

    Samples needed in supervising and check of operational parameters of a pilot installation for tritium and deuterium separation may have rather different values of the tritium activity ranging for instance from 10,000-18,000 TU, in case of heavy water feeding, to 10-20 TU, in case of the depleted water after separation. To measure activity in such a large range, a liquid scintillator counting method was chosen utilizing the low level counting spectrometer Quantulus 1220. For the calculation of efficiency and correction for attenuation in heavy water samples the methods of both internal and external standard were studied. The latter one proved to have too low measurement accuracy so the former one was adopted. A spectra library was constituted. Concentration determinations were done for both deuterium and tritium in a sample of heavy water of D/D+H = 99.66% concentration which was then diluted by a factor of 2, 4, 6, 8, 16 and 32. A good correlation with the dilution factors was found for the two hydrogen isotopes

  4. Spatial and seasonal variation in heavy metals in interstitial water of salt marsh soils

    International Nuclear Information System (INIS)

    Soil colonization by plants affected spatial and seasonal variation in heavy metals. - The composition of interstitial water collected from a salt marsh in NW Spain showed clear seasonal and spatial variations associated with redox cycles of Fe and S. In the summer, salinity increased in all soils as a consequence of the increase in evapotranspiration. The pH and concentrations of heavy metals also differed with season, but not all environments showed the same variations. Soils not colonized by plants had the highest pH and lowest heavy metal concentrations in the summer. These results support the idea that higher temperatures lead to an increase in the activity of sulfate-reducing bacteria, which in turn leads to an increase in alkalinity and concentration of sulfides in the water. Trace metals tend to precipitate with sulfides under these conditions and are removed from the interstitial water. In contrast, in the soils colonized by Spartina maritima, the oxidation of metal sulfides during the summer led to a decrease in pH and an increase in the metal concentrations in the interstitial water. The results obtained concur with those found for seasonal variations in metal sulfides in soils from the same salt marsh

  5. Analysis of severe accidents in pressurized heavy water reactors

    International Nuclear Information System (INIS)

    Certain very low probability plant states that are beyond design basis accident conditions and which may arise owing to multiple failures of safety systems leading to significant core degradation may jeopardize the integrity of many or all the barriers to the release of radioactive material. Such event sequences are called severe accidents. It is required in the IAEA Safety Requirements publication on Safety of the Nuclear Power Plants: Design, that consideration be given to severe accident sequences, using a combination of engineering judgement and probabilistic methods, to determine those sequences for which reasonably practicable preventive or mitigatory measures can be identified. Acceptable measures need not involve the application of conservative engineering practices used in setting and evaluating design basis accidents, but rather should be based on realistic or best estimate assumptions, methods and analytical criteria. Recently, the IAEA developed a Safety Report on Approaches and Tools for Severe Accident Analysis. This publication provides a description of factors important to severe accident analysis, an overview of severe accident phenomena and the current status in their modelling, categorization of available computer codes, and differences in approaches for various applications of severe accident analysis. The report covers both the in- and ex-vessel phases of severe accidents. The publication is consistent with the IAEA Safety Report on Accident Analysis for Nuclear Power Plants and can be considered as a complementary report specifically devoted to the analysis of severe accidents. Although the report does not explicitly differentiate among various reactor types, it has been written essentially on the basis of available knowledge and databases developed for light water reactors. Therefore its application is mostly oriented towards PWRs and BWRs and, to a more limited extent, they can be only used as preliminary guidance for other types of reactors

  6. Studies on heavy charged particle interaction, water equivalence and Monte Carlo simulation in some gel dosimeters, water, human tissues and water phantoms

    Science.gov (United States)

    Kurudirek, Murat

    2015-09-01

    Some gel dosimeters, water, human tissues and water phantoms were investigated with respect to their radiological properties in the energy region 10 keV-10 MeV. The effective atomic numbers (Zeff) and electron densities (Ne) for some heavy charged particles such as protons, He ions, B ions and C ions have been calculated for the first time for Fricke, MAGIC, MAGAT, PAGAT, PRESAGE, water, adipose tissue, muscle skeletal (ICRP), muscle striated (ICRU), plastic water, WT1 and RW3 using mass stopping powers from SRIM Monte Carlo software. The ranges and straggling were also calculated for the given materials. Two different set of mass stopping powers were used to calculate Zeff for comparison. The water equivalence of the given materials was also determined based on the results obtained. The Monte Carlo simulation of the charged particle transport was also done using SRIM code. The heavy ion distribution along with its parameters were shown for the given materials for different heavy ions. Also the energy loss and damage events in water when irradiated with 100 keV heavy ions were studied in detail.

  7. A water-in-oil emulsion containing Kelex-100 for the speciation analysis of trace heavy metals in water

    International Nuclear Information System (INIS)

    A water-in-oil (w/o) emulsion containing Kelex-100 (7-dodecenyl-8-quinolinol) and Span-80 (sorbitan monooleate, non-ionic surfactant) was ultrasonically prepared from 1.0 mol l-1 hydrochloric acid and a (1 + 3) mixture of toluene and n-heptane. The resulting emulsion was gradually injected into water sample and dispersed as numerous tiny globules (0.01-0.1 mm in diameter). Dissolved inorganic species (free metal species) of heavy metals (e.g., Fe, Co, Cu, Cd, and Pb) were selectively transported through the oil layer into the internal aqueous phase of the emulsion, leaving other species, such as humic complexes and suspended particles (larger than 1 μm), in the sample solution. After collecting the dispersed emulsion globules, they were demulsified and the heavy metals in the segregated aqueous phase were determined by graphite-furnace atomic absorption spectrometry. The emulsion-based separation method allowed the selective collection of free metal species with a high concentration factor of 100, whereas the conventional solvent extraction did not offer such discrimination. This unique property of the emulsion method was successfully applied to the selective determination of free species of heavy metals in fresh water samples

  8. An advanced field experimental design to assess plant tolerance to heavy metal pollution

    Science.gov (United States)

    Łopata, Barbara; Szarek-Łukaszewska, Grażyna; Babst-Kostecka, Alicja

    2016-04-01

    Only a limited number of vascular plant species can survive and reproduce in toxic metalliferous environments. Among these species, pseudometallophytes are particularly interesting, as their metallicolous (M) populations on metalliferous soils and non-metallicolous (NM) populations on non-metalliferous soils show very pronounced ecological differences. Pseudometallophytes thus provide excellent opportunities for multidisciplinary research to improve phytoremediation and phytomining. Numerous methods have been developed to investigate plant adaptation to metal pollution, the majority of which has been conducted under controlled laboratory conditions. Although these efforts have significantly advanced our understanding of mechanisms underlying metal tolerance in plants, populations must be reciprocally transplanted to clearly identify natural selection. Only then is it possible to test, whether the fitness of native plants is higher than that of nonnative populations and thereby prove local adaptation. Here, we present an enhanced field experimental design aimed at verification of local adaptation to habitats with different levels of heavy metal soil contamination. At two M and two NM sites, we established a total of 12 plots (4 sites x 3 plots each), removed the existing local vegetation, and collected soil samples for chemical analyses (5 samples per plot). Plant collection (N= 480) from all four selected populations was established under laboratory conditions prior to the transplant experiment. Genotypes were randomly distributed within each plot (240 x 270 cm) and planted along a regulary spaced grid (30x30cm cell size) in spring 2015. Measurements will start in spring 2016, by which time plants are expected to have acclimatized to the local conditions. For the two subsiquent years, growth, survival, fitness, life cycle and herbivory consumption will be monitored for each transplant. On a weekly basis, we will record: 1) pictures of each transplant to determine

  9. International conference on Future of Heavy Water Reactors (HWR-FUTURE)

    International Nuclear Information System (INIS)

    The International Conference on Future of Heavy Water Reactors (HWR-FUTURE) was held in Ottawa, Ontario, Canada on October 2-5, 2011. The conference comprised of various case studies, presentations and roundtable discussions on several pertinent topics dealing with the fast emerging Heavy Water Reactor or HWR technology. This conference addressed the challenges faced by the sector and assisted in planning feasible methods to combat them. Emphasizing effectively on developments and issues, knowledge exchange and technology transfer, and establishing prospective collaborations on reactor design, fuel design, material and chemistry, thermal hydraulics and safety, and operating experience for HWRs, presented were paper presentations, plenary sessions, live demos and practical solutions pertaining to these issues.

  10. Probabilistic consequence assessment of hydrogen sulphide releases from a heavy water plant

    International Nuclear Information System (INIS)

    This report provides a summary of work carried out on behalf of the Atomic Energy Control Board, concerned with the consequences of accidental releases to the atmosphere of hydrogen sulphide (H2S) at a heavy water plant. In this study, assessments of consequences are made in terms of the probabilities of a range of possible outcomes, i.e., numbers of fatalities, given a certain release scenario. The report describes the major features of a computer model which was developed to calculate the consequences and their associated probabilities, and the major input data used in applying the model to a consequence assessment of the Bruce heavy water plant (HWP) in Ontario. The results of the sensitivity analyses of the model are summarized. Finally, the results of the consequence assessments of 43 accidental release scenarios at the Bruce HWP are summarized, together with a number of conclusions which were drawn from these results regarding the predicted consequences and the factors which influence them

  11. Acidification of Harbour sediment and removal of heavy metals induced by water splitting in electrodialytic remediation

    DEFF Research Database (Denmark)

    Nystrøm, Gunvor Marie; Ottosen, Lisbeth M.; Villumsen, Arne

    2005-01-01

    Harbor sediments are often contaminated with heavy metals, which can be removed by electrodialytic remediation. Water splitting at the anion exchange membrane in contact with the contaminated material in electrodialytic remediation is highly important for the removal of heavy metals. Here it was...... investigated how acidification caused by water splitting at the anion exchange membrane during electrodialytic remediation of contaminated harbor sediment and hence the metal removal, was influenced by different experimental conditions. Two different experimental cells were tested, where the number of...... sediment was acidified, the voltage decreased and electrical conductivity increased. After 5 days of remediation the sediment was acidified at the chosen current density (1 mA/cm(2)) and the main metal removal was observed shortly after. Thus it was crucial for the metal removal that the sediment was fully...

  12. Photoneutron compensating method for boric acid concentration measuring instrument in heavy water moderated reactor

    International Nuclear Information System (INIS)

    In a boric acid concentration measuring instrument in a heavy water moderated reactor, a portion of γ-ray from Na-24 and Mn-56 is reacted with heavy water to form photoneutrons. The photoneutrons cause errors in the measurement for B-10 concentration. Then, in the present invention, a sample liquid containing photoneutron sources is supplied during normal measurement and a sample liquid removed with the photoneutron sources by passing through an ion exchange resin tower is supplied upon calibration of the measuring instrument. Then, the extent for the of effect of neutron sources and γ-nuclides is obtained by calculation from the measuring value to calibration the extent of the photoneutrons. Further, a method of using a counter tube having a Cd filter is used in combination during normal measurement to enable continuous measurement without exchanging the sample liquid. Accordingly, the influence of photoneutrons can be compensated and boric acid concentration can be measured at high accuracy. (N.H.)

  13. Preparation of gas sealed high isotopic purity heavy water reference standards

    International Nuclear Information System (INIS)

    The method for preparation of helium gas sealed high isotopic purity heavy water (D2O) reference standards has been amply demonstrated. The percentage purity of the reference standards has been confirmed employing Fourier-Transform Infrared (FT-IR) method standardized with certified D2O standards having an accuracy of ± 0.01 wt.% each. The work has also been extended in the preparation of high purity reference standards (99.86 wt.%, 99.90 wt.% and 99.96 wt.%) with accuracy of ± 0.01 wt.% in stainless steel containers (total 15 Nos.) in collaboration with Heavy Water Plant (HWP) laboratory, Baroda. The standards prepared here are extremely useful for day-to-day quality control of product D2O as well as certifying the quality of export consignments from different HWPs. (author)

  14. Data acquisition and control system for a heavy water detritiation plant

    International Nuclear Information System (INIS)

    The importance of detritiation of heavy water in CANDU type reactors is well known, due to the implications of detritiation in fusion processes and installations. The nature of the fluids that are processed in detritiation requires the operation of the plant in maximum safety conditions in order to protect the working staff and environment. The paper presents the data acquisition and control system for an experimental heavy water detritiation plant. The plant must be designed to be operated without any working staff in the technological space. The purpose of the safety and control system is to ensure an irradiation risk below the prescription limits. The radiological risk is the tritium leakage as gas, vapors or liquid. (author)

  15. Product yields in water radiolysis with heavy ions relevant to track structures

    International Nuclear Information System (INIS)

    Radiolysis of neutral water with high-energy heavy ions has been investigated since FY 2002. It has been purposed to clarify track structure and its dynamics. Until the end of FY 2007, following 3 things has been accomplished. (A) primary yields, which are defined as yields approximately at 100 ns after radiation passage, of main products have widely been determined, (B) Temporal behavior of water decomposition radicals during ns-μs has been investigated, and (C) a sensitive method to determine Hydroxyl radical OH yield has also been developed and applied to heavy ion irradiations. In FY 2008, (A) and (C) are extended to higher linear energy transfer (LET) regions by using energy absorber at the upstream or by taking heavier ions, Kr and Xe. In addition, (C) was also applied in (D) challenge to scrutinize Hydroxyl radical OH yield near and at the Bragg peak. (author)

  16. Product yields of water radiolysis with heavy ions relevant to track structures

    International Nuclear Information System (INIS)

    Radiolysis of neutral water with high-energy heavy ions has been investigated since the FY 2002, purposing to clarify structure of heavy ions and intra-track dynamics by measuring product yields, which are macroscopically measurable. Until the FY 2009, following 4 things have been accomplished: (A) primary yield measurement, (B) investigation on intra-track dynamics, (C) sensitive determination of Hydroxyl radical (·OH) yields, (D) extension of (C) to the Bragg peak. In the FY 2010, we tried to explain our experimental data obtained in the activity (D) by considering beam quality change in water due to nuclear fragmentations by using PHITS code. A new challenge to develop an online gas analysis system was also promoted. (author)

  17. Recent advances in biosorption of heavy metals: support tools for biosorption equilibrium, kinetics and mechanism

    OpenAIRE

    Hlihor, Raluca Maria; Bulgariu, Laura; Sobariu, Dana Luminita; Diaconu, Mariana; Tavares, T.; Gavrilescu, Maria

    2014-01-01

    Heavy metals are increasingly present in industrial wastes and effluents, which can generate serious concerns for environmental quality and human health. Consequently, there is a continuous expansion of researches for new approaches and developments to guarantee environmental cleaning-up. Although there are some physico-chemical established methods for the removal of heavy metals from various environmental compartments, biosorption gains further confidence as a reliable a...

  18. Thermophysical properties database of materials for light water reactors and heavy water reactors. Final report of a coordinated research project 1999-2005

    International Nuclear Information System (INIS)

    The IAEA Coordinated Research Project (CRP) on the Establishment of a Thermo-physical Properties Database for Light Water Reactors (LWRs) and Heavy Water Reactors (HWRs) started in 1999. It was included in the IAEA's Nuclear Power Programme following endorsement in 1997 by the IAEA's Technical Working Groups on Advanced Technologies for LWRs and HWRs (the TWG-LWR and the TWG-HWR). Furthermore, the TWG on Fuel Performance and Technology (TWG-FPT) also expressed its support. This CRP was conducted as a joint task within the IAEA's project on technology development for LWRs and HWRs in its nuclear power programme. Improving the technology for nuclear reactors through better computer codes and more accurate materials property data can contribute to improved economics of future plants by helping to remove the need for large design margins, which are currently used to account for limitations of data and methods. Accurate representations of thermo-physical properties under relevant temperature and neutron fluence conditions are necessary for evaluating reactor performance under normal operation and accident conditions. The objective of this CRP was to collect and systematize a thermo-physical properties database for light and heavy water reactor materials under normal operating, transient and accident conditions and to foster the exchange of non-proprietary information on thermo-physical properties of LWR and HWR materials. An internationally available, peer reviewed database of properties at normal and severe accident conditions has been established on the Internet. This report is intended to serve as a useful source of information on thermo-physical properties data for water cooled reactor analyses. The properties data have been initially stored in the THERSYST data system at the University of Stuttgart, Germany, which was subsequently developed into an internationally available Internet database named THERPRO at Hanyang University, Republic of Korea

  19. National symposium on commissioning and operating experiences in heavy water plants and associated chemical industries [Preprint volume

    International Nuclear Information System (INIS)

    A symposium on commissioning and operating experiences in heavy water plants and associated chemical industries (SCOPEX-92) was organised to share the experience and exchange the ideas among plant operators, designers, consultants and vendors in the areas of operation, commissioning and equipment performance. This pre-print volume has been brought out as an integrated source of information on commissioning and operation of heavy water plants. The following aspects of heavy water plants are covered: commissioning and operation, instrumentation and control, and safety and environment. (V.R.)

  20. Levels of Organochlorine Pesticides and Heavy Metals in Surface Waters of Konya Closed Basin, Turkey

    OpenAIRE

    Mehmet Emin Aydin; Senar Ozcan; Fatma Beduk; Ali Tor

    2013-01-01

    The concentrations of organochlorine pesticides (OCPs), including α -, β -, γ -, and δ -hexachlorocyclohexane (HCH), heptachlor, heptachlor epoxide, dieldrin, aldrin, endrin, endrin aldehyde, endrin ketone, endosulfan I, endosulfan II, endosulfan sulfate, p,p′-DDE, p,p′-DDD, p,p′-DDT, methoxychlor, chlordane I, chlordane II, and heavy metals, such as As, Cr, Cu, Fe, Mn, and Ni in surface water samples from the Konya closed basin were determined to evaluate the level of contamination. Among al...

  1. Innovation in laboratory analysis in heavy water plants (Paper No. 6.7)

    International Nuclear Information System (INIS)

    Heavy Water Plant (Baroda) is operated with the laboratory's analytical support averaging 50,000 measurements on 22,000 samples per annum apart from various experiments and tests for problem solving and for indigenisation of process parameters. Each measurement has its own importance in attaining the optimised process and quality controls for sustained operation of the plant. This paper attempts to discuss the importance of laboratory analysis. (author). 7 refs

  2. Possibilities for use of natural raw materials in treatment of mine water contaminated with heavy metals

    OpenAIRE

    Zendelska, Afrodita

    2015-01-01

    This doctoral dissertation examines the possibility of applying natural raw materials such as clinoptilolite, stilbite and opalitized tuff in removing heavy metals (Pb, Zn, Mn и Cu) from contaminated mine water. The basic examination of these natural raw materials led to the conclusion that the stilbite gives best results, a little lower efficiency is noted for the clinoptilolite, while the opalitized tuff shows the smallest power of absorption compared to that of the stilbite and the clin...

  3. The response time analysis of high log neutron flux rate for heavy water reactors

    International Nuclear Information System (INIS)

    The heavy water reactor such as Wolssung no. 1 has a protection/safety system named special safety system. The system has four safety systems ; shutdown no. 1, shutdown no. 2, emergency core cooling system and containment system. In this paper, the response time of high log neutron flux rate, one of the reactor trip loops of shutdown no.1/no.2, was analysed based on the description of final safety analysis report and compared to the plant measurement

  4. Heavy water effects on the structure, functions and behavior of biological systems

    International Nuclear Information System (INIS)

    The H2O substitution for D2O either in environment or in the culture medium of the living systems generates changes in their main functions and composition. In this paper some of the heavy water effects in biological systems such as structural and functional changes were reviewed: normal cell architecture alterations, cell division and membrane functions disturbance, muscular contractility and the perturbations of biological oscillators such as circadian rhythm, heart rate, respiratory cycle, tidal and ultradian rhythm. (authors)

  5. Heavy metals in soil and water near mercury hotspots in Guizhou, China

    OpenAIRE

    2008-01-01

    Chinas fast-growing economy has led to an increase in the releases of many heavy metals. These releases affect both the local environment through soil and water contamination, but also the regional and global environment as many metals can be transported thousands of kilometres away from their original source through the atmosphere. The Sino-Norwegian Cooperation Project on Mercury Pollution (SINOMER) focuses on mercury releases in the People’s Republic of China, with Guizhou province as case...

  6. Influence of heavy metals pollution in borehole water collected within abandoned battery industry, Essien Udim, Nigeria

    OpenAIRE

    Uffia, I. Dan; Etim D. E

    2013-01-01

    Physico-chemical and heavy metals analyses of water samples from three boreholes located within abandoned battery company in Essien Udim LGA, Akwa Ibom State, Nigeria was carried out to ascertain the impact of pollution from battery industry on groundwater quality. Borehole locations were at different distances of 0km, 2km, and 5km (X1, X11 and X111) respectively away from the abandoned battery vicinity. The parameters determined included; turbidity, temperature, pH, Dissolved oxygen (DO), ...

  7. Preparation Before Signature of Upgrade of Algeria Heavy Water Research Reactor Contract

    Institute of Scientific and Technical Information of China (English)

    LI; Song; ZAN; Huai-qi; XU; Qi-guo; JIA; Yu-wen

    2012-01-01

    <正>Algeria heavy water research reactor (Birine) is a multiple-purpose research reactor, which was constructed with the help of China more than 20 years ago. By request of Algeria, China will upgrade the research reactor; so as to improve the status of current reactor such as equipment ageing, shortage of spare parts, several systems do not meet requirements of current standards and criteria etc.

  8. Incorporating outage management principles into the advanced light water reactor

    International Nuclear Information System (INIS)

    In the United States there are 110 light water reactor (LWR) plants currently in operation, with a total generating capacity of 102 580 MW(electric). These plants include 37 boiling water reactor (BWR) and 73 pressurized water reactor (PWR) units. Since 1980, more than 40 nuclear power plants have entered service in the United States. However, no new plants have been ordered by utilities and owners groups since 1978. There will come a time in the not-too-distant future that new, large electricity generating units will be needed to supply expected increases in base-load capacity. Will the new advanced LWR (ALWR) designs be able to pass muster and be chosen to help meet that need? With outage management at operating plants improving every year, what can the ALWR designs offer that has not already been incorporated?

  9. Effects of lime on bioavailability and leachability of heavy metals during agitated pile composting of water hyacinth.

    Science.gov (United States)

    Singh, Jiwan; Kalamdhad, Ajay S

    2013-06-01

    In the present study composting of water hyacinth was done with cattle manure and saw dust (6:3:1) ratio and effects of addition of lime (1%, 2% and 3%) on heavy metal bioavailability and leachability was evaluated during 30 days of composting period. The changes in temperature, pH, electrical conductivity (EC), organic matter and extractable heavy metal contents were measured. Results showed that the total concentration of heavy metals was increased during the composting process. Due to addition of lime initial pH of the compost was raised effectively, caused a decrease in water soluble, diethylene triamine pentracetic acid (DTPA) and toxicity characteristics leaching procedure (TCLP) extractable metal contents in the final compost. Water soluble metals (Ni, Pb and Cd) and DTPA extractable metals (Pb and Cd) were not detected during water soluble fraction. Addition of lime significantly reduced the bioavailability and leachability of heavy metals during water hyacinth composting process. PMID:23612174

  10. Colloid-borne uranium and other heavy metals in the water of a mine drainage gallery

    International Nuclear Information System (INIS)

    The water of a mine drainage gallery was investigated for its contents of colloid-borne heavy metals with emphasis on uranium. About 1 mg/L of colloid particles of 100 to 300 nm were found. They consist of a matrix of Fe and Al oxyhydroxides and are formed when anoxic slightly acidic shaft waters mix with oxic near-neutral gallery water. The colloid particles bear toxic trace elements such as As, Pb, and Cu. Almost 100% of the As and Pb and about 70% of the Cu contained in the water are colloid-borne. Carbonato complexes prevent the uranyl from being adsorbed on the colloids in the unaltered gallery water. Acidification destroys these complexes: up to 50% of the uranium is attached to the colloids in the slightly acidic pH region. Further acidification converts the uranyl again to a 'non-colloidal' form. (orig.)

  11. Levels of Organochlorine Pesticides and Heavy Metals in Surface Waters of Konya Closed Basin, Turkey

    Directory of Open Access Journals (Sweden)

    Mehmet Emin Aydin

    2013-01-01

    Full Text Available The concentrations of organochlorine pesticides (OCPs, including α-, β-, γ-, and δ-hexachlorocyclohexane (HCH, heptachlor, heptachlor epoxide, dieldrin, aldrin, endrin, endrin aldehyde, endrin ketone, endosulfan I, endosulfan II, endosulfan sulfate, p,p′-DDE, p,p′-DDD, p,p′-DDT, methoxychlor, chlordane I, chlordane II, and heavy metals, such as As, Cr, Cu, Fe, Mn, and Ni in surface water samples from the Konya closed basin were determined to evaluate the level of contamination. Among all HCH isomers, β-HCH is the main isomer with a concentration range of 0.015–0.065 μg/L. DDE, DDD, and DDT were almost determined in all samples, in which DDE isomer had the highest concentration ranged from not detected to 0.037 μg/L. In all studied OCPs, aldrin showed the highest concentration at 0.220 μg/L. The concentrations of heavy metals in water samples were observed with order: Mn < Cu < Ni < As < Cr < Fe. In some samples, As, Fe, and Cr concentrations exceeded the drinking water quality recommended by EU, US EPA, WHO, and Turkish Regulation, while Cu, Ni, and Mn concentrations are below the guideline values. The levels of both OCPs and heavy metals were also compared with other previously published data.

  12. Depollution of water contaminated by heavy metals using beetroot fibers as biofilter

    International Nuclear Information System (INIS)

    Author.We are reported for the first time the use of Beetroot fibers to eliminate heavy metals from water polluted and wastewater. This biomass is used to remove lead, copper and zinc ions from polluted water and industrial effluent. We were mainly interested in beetroot fibers that constitute an important deposit of cheap and low value biomass. In our paper, kinetics and beetroot fibers fixation capacities of lead, copper and zinc according to various physico-chemicals parameters such as p H, and the concentration of metallic solutions were studied. Fixation experiences were carried out in laboratory column with fixed bed. Biomass was used without any treatment. For the kinetic studies, samples of metallic solutions were done at regular intervals by filtering, diluted then measured out by atomic absorption spectrometry. The effect of p H on the fixation of metallic ions by the beetroot fibers and the retention of metal cations on the bio filter fixation capacity were studied. The retention of lead, copper and zinc by beetroot fibers ((8%, 92% and 90% respectively) indicated the relative importance of this biomass in the remediation process of water contamination by heavy metals. This approach has been found rapid, practical and efficient for a variety of mixture of heavy metals

  13. Heavy water production benefits of a supporting r and d program

    International Nuclear Information System (INIS)

    Considerable economic benefit was obtained from an active R and D program while the Canadian heavy water plants were brought to mature operation during the 1970s. The introduction to Canada of this new chemical processing industry led to unexpected process, equipment and materials problems. Having a small team of technical experts already working on heavy water processes and a much larger R and D team working in related fields allowed a rapid response to the problems that limited production. The number of engineers and scientists working on the GS process rose rapidly from a skeleton team in 1970 to 54 during 1974. Effort declined steadily as the major problems were solved and reached 22 by 1980. Cumulative effort over the decade was 264 man-years at a cost of 3.3 percent of the value of the heavy water produced. The new production benefits have lagged behind the R and D expenditure by a few years and the current spending rate is 1.2 percent of product value. Important contributions were made in the areas of process simulation, process chemistry, materials of construction, sieve trays, and mechanical equipment

  14. Production of a New Emulsifier Material for the Formation Heavy Hydrocarbon/Water Emulsion

    Directory of Open Access Journals (Sweden)

    Afshin Farahbakhsh

    2011-04-01

    Full Text Available Emulsifiers are a unique class of compounds that have proved to have a variety of potential applications in formation of hydrocarbon in water emulsion, in enhancement of oil recovery and in the reduction of heavy oil viscosity. In this paper, a bio emulsifier was synthesized by a strain of Bacillus licheniformis and was separated by an autoclave and centrifugal process; the purification of bio emulsifier and the increase quality of product was done by adding sulfuric acid (H2SO4 (98% to the solution and centrifuging this compound again. This bio emulsifier has the property of emulsification to a wide range of heavy hydrocarbon to form a stable hydrocarbon-water emulsion. This bio emulsifier could reduce Iranian Nuroze high viscosity oil of about 10000 cP down to 250 cP. This means about 97% decreases in the viscosity. The emulsion stable this condition for 48 hr and the viscosity slowly increases to 4000cp until 192 hr. The stability of the oil in water emulsion during 48hr allows the heavy oil to be transported practically over lengthy distances or remain stable for long periods of time prior to utilization.

  15. A study of the tritium behavior in coolant and moderator system of heavy water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. P.; Song, S. S.; Chae, K. S. and others [Chosun Univ., Gwangju (Korea, Republic of)

    1993-12-15

    The objectives of this report is to present a regulatory policy on the environmental impact and personnel exposure by understanding the generation, accumulation, environmental release and management of tritium in heavy water reactors. By estimating the tritium concentration at Wolsong nuclear plant site by estimating and forecasting the generation and accumulation of tritium in coolant and moderator systems at Wolsong unit 1, we will study the management and release of tritium at Wolsong units 3 and 4 which are ready for construction. The major activities of this study are as follows : tritium generation and accumulation in heavy water reactor, a quantitative assessment of the accumulation and release of tritium at Wolsong nuclear plant site, heavy water management at Wolsong nuclear plants. The tritium concentration and accumulation trends in the systems at Wolsong unit 1 was estimated. A quantitative assessment of the tritium accumulation and release for Wolsong 2, 3 and 4 based on data from Wolsong 1 was performed. The tritium removal schemes and its long-term management plan were made.

  16. Seasonal assessment, treatment and removal of heavy metal concentrations in a tropical drinking water reservoir

    Directory of Open Access Journals (Sweden)

    Mustapha Moshood Keke

    2016-06-01

    Full Text Available Heavy metals are present in low concentrations in reservoirs, but seasonal anthropogenic activities usually elevate the concentrations to a level that could become a health hazard. The dry season concentrations of cadmium, copper, iron, lead, mercury, nickel and zinc were assessed from three sites for 12 weeks in Oyun reservoir, Offa, Nigeria. Triplicate surface water samples were collected and analysed using atomic absorption spectrophotometry. The trend in the level of concentrations in the three sites is site C > B > A, while the trend in the levels of the concentrations in the reservoir is Ni > Fe > Zn > Pb > Cd > Cu > Hg. Ni, Cd, Pb and Hg were found to be higher than the WHO guidelines for the metals in drinking water. The high concentration of these metals was from anthropogenic watershed run-off of industrial effluents, domestic sewages and agricultural materials into the reservoir coming from several human activities such as washing, bathing, fish smoking, especially in site C. The health effects of high concentration of these metals in the reservoir were highlighted. Methods for the treatment and removal of the heavy metals from the reservoir during water purification such as active carbon adsorption, coagulation-flocculation, oxidation-filtration, softening treatment and reverse osmosis process were highlighted. Other methods that could be used include phytoremediation, rhizofiltration, bisorption and bioremediation. Watershed best management practices (BMP remains the best solution to reduce the intrusion of the heavy metals from the watershed into the reservoir.

  17. Technologies for tritium control in fission reactors moderated with heavy water

    International Nuclear Information System (INIS)

    This study was done within a program one of whose objectives was to analyze the possible strategies and technologies, to be applied to HWR at Argentine nuclear power plants, for tritium control. The high contribution of tritium to the total dose has given rise to the need by the operators and/or designers to carry out developments and improvements to try to optimize tritium control technologies. Within a tritium control program, only that one which includes the heavy water detritiation will allow to reduce the tritium concentrations at optimum levels for safety and cost-effective power plant operation. The technology chosen to be applied should depend not only on the technical feasibility but also on the analysis of economic and juncture factors such as, among others, the quantity of heavy water to be treated. It is the authors' belief that AECL tendency concerning heavy water treatment in its future reactors would be to employ the CECE technology complemented with immobilization on titanium beds, with the 'on-line' detritiation in each nuclear power plant. This would not be of immediate application since our analysis suggests that AECL would assume that the process is under development and needs to be tested. (author). 21 refs

  18. Levels of organochlorine pesticides and heavy metals in surface waters of Konya closed basin, Turkey.

    Science.gov (United States)

    Aydin, Mehmet Emin; Ozcan, Senar; Beduk, Fatma; Tor, Ali

    2013-01-01

    The concentrations of organochlorine pesticides (OCPs), including α -, β -, γ -, and δ -hexachlorocyclohexane (HCH), heptachlor, heptachlor epoxide, dieldrin, aldrin, endrin, endrin aldehyde, endrin ketone, endosulfan I, endosulfan II, endosulfan sulfate, p,p'-DDE, p,p'-DDD, p,p'-DDT, methoxychlor, chlordane I, chlordane II, and heavy metals, such as As, Cr, Cu, Fe, Mn, and Ni in surface water samples from the Konya closed basin were determined to evaluate the level of contamination. Among all HCH isomers, β -HCH is the main isomer with a concentration range of 0.015-0.065 μ g/L. DDE, DDD, and DDT were almost determined in all samples, in which DDE isomer had the highest concentration ranged from not detected to 0.037 μ g/L. In all studied OCPs, aldrin showed the highest concentration at 0.220 μ g/L. The concentrations of heavy metals in water samples were observed with order: Mnwater quality recommended by EU, US EPA, WHO, and Turkish Regulation, while Cu, Ni, and Mn concentrations are below the guideline values. The levels of both OCPs and heavy metals were also compared with other previously published data. PMID:23533363

  19. HEAVY METAL ANALYSIS IN WASTE WATER SAMPLES FROM VALEA ŞESEI TAILING POND

    Directory of Open Access Journals (Sweden)

    I. L. MELENTI

    2011-03-01

    Full Text Available Heavy metal analysis in waste water samples from Valea Şesei tailing pond. The mining of ore deposits and the processing and smelting of copper at Roşia Poieni have resulted in an increase of the toxic elements concentration within all components of the environment in the area. Valea Şesei tailing pond is a waste deposit for the Roşia Poieni open-pit and is the biggest tailing pond in Romania. In October 2009, we determined 8 heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Ni and Zn in 10 waste water samples. This water flows under the tailing dam, through the Valea Şesei stream, into the Arieş River, the water’s pH varies between 3 and 4. The heavy metals concentration exceeds with orders of magnitude. In the stream the concentrations are much lower, but still exceed the admitted levels. The results show that the tailing pond is a pollution hot spot in the area affecting the environment.

  20. Correlation of Heavy Element in Sea Water and Sediment Samples from Peninsula of Muria

    International Nuclear Information System (INIS)

    The analysis of heavy metals in marine environmental samples peninsula of Muria in the year 2004 has been carried out by using neutron activation analysis (NAA) method. The objective of this analysis is to know the distribution of heavy metals in the sea water and sediment, which accommodate the recent environmental data in supporting the license of site for the nuclear power plants (NPP). The result of the analysis show that there were only 5 observed elements found in sea water and sediment were Cd, Co, Cr, Sb and Sc. All of heavy metals from sea water (0.002 mg/l) are obviously lower than the threshold value established by environmental minister Act; Kep LH No 51/2004. From the observed data to use software of SPSS version 10, application of the Pearson correlation (r) shows that between Co with Sc was indicator show a highly positive significant correlation (r=0.928), between Cr with Sc was sufficiently positive high (r=0.756), between Cr with Cd was precisely (r=0.611) while Co with Sb shows the significantly low (r=0.429). (author)

  1. Turning the volume down on heavy metals using tuned diatomite. A review of diatomite and modified diatomite for the extraction of heavy metals from water

    Energy Technology Data Exchange (ETDEWEB)

    Danil de Namor, Angela F., E-mail: A.Danil-De-Namor@surrey.ac.uk [Instituto Nacional de Tecnologia Industrial, Parque Tecnologico Industrial Miguelete, Buenos Aires (Argentina); Department of Chemistry, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); El Gamouz, Abdelaziz [Department of Chemistry, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); Frangie, Sofia; Martinez, Vanina; Valiente, Liliana [Instituto Nacional de Tecnologia Industrial, Parque Tecnologico Industrial Miguelete, Buenos Aires (Argentina); Webb, Oliver A. [Department of Chemistry, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer Critical assessment of published work on raw and modified diatomites. Black-Right-Pointing-Pointer Counter-ion effect on the extraction of heavy metal speciation by diatomite. Black-Right-Pointing-Pointer Selection of the counter-ion by the use of existing thermodynamic data. Black-Right-Pointing-Pointer Enrichment of diatomites by attaching heavy metal selective functionalities. Black-Right-Pointing-Pointer Supramolecular chemistry for conferring selectivity to diatomites. - Abstract: Contamination of water by heavy metals is a global problem, to which an inexpensive and simple solution is required. Within this context the unique properties of diatomite and its abundance in many regions of the world have led to the current widespread interest in this material for water purification purposes. Defined sections on articles published on the use of raw and modified diatomite for the removal of heavy metal pollutants from water are critically reviewed. The capability of the materials as extracting agents for individual species and mixtures of heavy metals are considered in terms of the kinetics, the thermodynamics and the recyclability for both, the pollutant and the extracting material. The concept of 'selectivity' for the enrichment of naturally occurring materials such as diatomite through the introduction of suitable functionalities in their structure to target a given pollutant is emphasised. Suggestions for further research in this area are given.

  2. Water production in extra heavy oil environment : controlling the risks, optimizing the production

    Energy Technology Data Exchange (ETDEWEB)

    Cermeno, E.; Draoui, E.; Gamez, Y.; Inizan, M.; Alves, Y. [Petrocedeno, Caracas (Venezuela)

    2008-07-01

    This paper reviewed reservoir completion technologies and strategies used at Orinoco Belt in Venezuela. The reservoir in the belt are fluvio-deltaic with higher permeability sand and a large regional aquifer that has contributed to the region's wide-ranging oil viscosities. Oilfields in the belt are typically produced using directional drilling techniques. Monitoring programs in the region have identified that water production from the aquifer is determined by water entry points. Wells accumulate large volumes of extra heavy oil (EHO) after water breakthrough. However, the risk of water interference between wells is high. Results of the monitoring programs were used to develop a water production policy that relies on weekly production follow-ups; analyses of structural, geological, and dynamic data in order to understand water production; and water invasion control techniques. The completion technique was adapted to high water cut wells and was designed to consider the use of electro-submersible pumps (ESP). Methods of producing water directly from the aquifer for subsequent re-injection are also being considered. Weekly production tests are currently being conducted on all producer wells. Water cut developments are identified, monitored and registered. Data is then integrated with static analysis from geologists in order to improve water production techniques. 3 refs., 10 figs.

  3. Introduction of advanced pressurized water reactors in France

    International Nuclear Information System (INIS)

    Designed >30 yr ago, pressurized water reactors (PWRs) have evolved well to match the current safety, operating, and economic requirements. The first advanced PWR generation, the N4 reactor, is under construction with 1992 as a target date for commercial operation. The N4 may be considered to be a technological outcome of PWR evolution, providing advances in the fields of safety, man/machine interfaces, and load flexibility. As a step beyond N4, a second advanced PWR generation is presently under definition with, as a main objective, a greater ability to cope with the possible deterioration of the natural uranium market. In 1986, Electricite de France (EdF) launched investigations into the possible characteristics of this advanced PWR, called REP-2000 (PWR-2000: the reactor for the next century). Framatome joined EdF in 1987 but had been working on a new tight-lattice reactor. Main options are due by 1988; preliminary studies will begin and, by 1990, detailed design will proceed with the intent of firm commitments for the first unit by 1995. Commissioning is planned in the early years of the next century. This reactor type should be either an improved version of the N4 reactor or a spectral shift convertible reactor (RCVS). Through research and development efforts, Framatome, Commissariat a l'Energie Atomique (CEA), and EdF are investigating the physics of fuel rod tight lattices including neutronics, thermohydraulics, fuel behavior, and reactor mechanics

  4. 76 FR 3540 - U.S. Advanced Boiling Water Reactor Aircraft Impact Design Certification Amendment

    Science.gov (United States)

    2011-01-20

    ... COMMISSION 10 CFR Part 52 RIN 3150-AI84 U.S. Advanced Boiling Water Reactor Aircraft Impact Design... the U.S. Advanced Boiling Water Reactor (ABWR) standard plant design to comply with the NRC's aircraft...--Design Certification Rule for the U.S. Advanced Boiling Water Reactor IV. Section-by-Section Analysis...

  5. Embedded optical fibers for PDV measurements in shock-loaded, light and heavy water

    Science.gov (United States)

    Mercier, Patrick; Benier, Jacky; Frugier, Pierre Antoine; Debruyne, Michel; Bolis, Cyril

    2012-03-01

    In order to study the shock-detonation transition, we propose to characterize the shock loading of a high explosive plane wave generator into a nitromethane cell. To eliminate the reactive behaviour, we replace the nitromethane by an inert liquid compound. Light water (H2O) has been first employed; eventually heavy water (D2O) has been chosen for its better infrared spectral properties. We present the PDV results of different embedded optical fibers which sense the medium with two different approaches: a non intrusive optical observation of phenomena coming in front of them (interface, shock wave, detonation wave) followed by their mechanical interaction with the fiber.

  6. Development of a microcontroller based monitor for measurement of tritium in heavy water

    International Nuclear Information System (INIS)

    A microcontroller based instrument for measurement of tritium in heavy water at concentration equal to or more than hundred milli-curie per litre is described. The tritium monitor has been designed using plastic scintillation film in a perspex cell and two photomultiplier tubes (PMTs) working in coincidence mode. The scintillation cell with coincidence electronics has a discrimination capability and enables to detect tritium in the presence of external gamma radiation. The monitor characteristics measured with tritiated water are presented. Sensitivity of the system is ∼ 460 CPS/Ci/litre under normal background level of 10-20 μR/hr. (author)

  7. Heavy metals in the surrounding water and sediments of tailing dam of Sasa mine

    OpenAIRE

    Zendelska, Afrodita; Golomeova, Mirjana; Krstev, Boris; Golomeov, Blagoj; Krstev, Aleksandar

    2011-01-01

    The paper shows results of tests on water and sediments quality in the Sasa Mine, along the Kamenicka and Bregalnica rivers flows into the Vardar River. The investigation results showed high concentrations of certain heavy metals (Mn, Zn, Cd, Pb and Cu) in water and sediments that pass or derived from the vicinity of the mine Sasa. The concentrations of these metals are highest near tailing dam of SASA mine. Going to the inflow into the Lake Kalimanci concentration of these metals are reduced...

  8. The advanced light water reactor program approach for gaining acceptance

    International Nuclear Information System (INIS)

    Electric utilities in the US face several obstacles and disincentives to building new nuclear power plants. A reformed licensing process that permits true one-step licensing is a prerequisite, as is timely implementation of the technical and political solutions of the high-level waste issue by the federal government and low-level waste storage by state governments. In addition, a more tangible acceptance of the need, benefits, and residual risk of nuclear power by all concerned institutions is an essential impetus for the return of the nuclear option. An improved version of the light water reactor (LWR) is expected to be the preferred choice for the next increment of nuclear capacity ordered in the US. The paper discusses the need for research and advanced LWR development. The advanced LWR program, sponsored jointly by the utility industry and the US Department of Energy (DOE), offers the most promising approach to developing the next generation of nuclear power plants

  9. Assessment of toxicity in waters due to heavy metals derived from atmospheric deposition using Vibrio fischeri.

    Science.gov (United States)

    Cukurluoglu, Sibel; Muezzinoglu, Aysen

    2013-01-01

    Water toxicity originating from the atmospheric deposition of six heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) was investigated on Vibrio fischeri activity in Izmir, Turkey. A LUMIStox® test was applied to dry and wet deposition samples and metal solutions. The inhibition levels and effective toxicity concentrations of these samples and solutions were determined. Interactive toxicity effects among the metals were investigated. When the impacts of the synthetic single heavy metal solutions were compared with each other, a toxicity ranking of Cr>Cd>Pb>Cu>Zn>Ni was obtained in order of decreasing severity. The total effective concentrations of these six metals were in the ranges of 0.074-0.221 mg/L and 0.071-0.225 mg/L for receiving aqueous solutions of dry and wet atmospheric depositions, respectively. The toxicity data showed that the wet deposition samples were 15% more toxic than the dry deposition samples. The interactive toxicity effects of the heavy metals in both dry and wet deposition samples were classified as antagonistic. High levels of heavy metals deposited in dissolved form may constitute an important input in the biochemical cycle and may have significant impacts. PMID:23030388

  10. Heavy metals in the waste and in the water discharge area of municipal solid waste

    Directory of Open Access Journals (Sweden)

    Luiz Ermindo Cavallet

    2013-12-01

    Full Text Available The county of Paranaguá discards 80 tons of municipal solid waste (MSW daily in the Embocuí landfill without proper treatment. The present study aimed to evaluate the concentration of arsenic (As, cadmium (Cd, chromium (Cr, lead (Pb and mercury (Hg in the dump area and to compare it with reference values for soil and water quality stipulated by CETESB (2005. The methodology of the study involved the collection of waste samples (organic waste mixed with soil from a depth of 1 m deep at 12 points of the dump, and the collection of water samples from a depth of 3 m at 3 points in the deposited waste. Extraction of heavy metals in the water samples was performed according to the USEPA (1999 method and analysis followed ICP-OES (Inductively Coupled Plasma - Atomic Emission Spectrometry. Analysis of the solid waste samples showed the following concentrations: (mg kg -1: As < 10; Cd < 1; Cr = 26; Pb = 52; e Hg = 0.2. The water samples showed the following concentrations: (mg L- 1: As < 5; Cd < 5; Cr =29 e Pb = 10. The amounts of heavy metals in samples of tailings and water from the landfill area fall below the values considered to create a risk of contamination.

  11. Separation of heavy metal from water samples--The study of the synthesis of complex compounds of heavy metal with dithiocarbamates.

    Science.gov (United States)

    Kane, Sonila; Lazo, Pranvera; Ylli, Fatos; Stafilov, Trajce; Qarri, Flora; Marku, Elda

    2016-01-01

    The toxicity and persistence of heavy metal (HM) ions may cause several problems to marine organisms and human beings. For this reason, it is growing the interest in the chemistry of sulphur donor ligands such as dithiocarbamates (DDTC), due to their applications particularly in analytical chemistry sciences. The aim of this work has been the study of heavy metal complexes with DDTC and their application in separation techniques for the preconcentration and/or removing of heavy metals from the water solutions or the water ecosystems prior to their analysis. The HM-DDTC complexes were prepared and characterized by elemental analysis, FTIR and UV-Vis spectroscopic methods. The elemental analysis and the yield of the synthesis (97.5-99.9%) revealed a good purity of the complexes. High values of complex formation yields of HM-DDTC complexes is an important parameter for quantitatively removing/and or preconcentration of heavy metal ions from water solution even at low concentration of heavy metals. Significant differences founded between the characteristic parameters of UV/Vis (λmax and ϵmax) and FTIR absorption spectra of the parent DDTC and HM-DDTC complexes revealed the complex formation. The presence of the peaks at the visible spectral zone is important to M(nd(10-m))-L electron charge transfer of the new complexes. The (C=N) (1450-1500 cm(-1)) and the un-splitting (C-S) band (950-1002 cm(-1)) in HM-DDTC FTIR spectra are important to the identification of their bidentate mode (HM[S2CNC4H10]2). The total CHCl3 extraction of trace level heavy metals from water samples after their complex formation with DDTC is reported in this article. PMID:26761072

  12. Assembly and use of permanent secondary standards for calibration of infrared spectrophotometer for determination of isotopic purity of nuclear grade heavy water

    International Nuclear Information System (INIS)

    Infrared spectrophotometer like any other instrument for quantitative or qualitative measurement of a property of a sample requires calibration or standardization with respect to a set of samples of known values of the parameter. For heavy water application, standards made out of nuclear grade heavy water are to be used. Since heavy water is hygroscopic in nature, standards tend to get degraded with time and thus shelf-life of heavy water standards is limited. Therefore, a paramount set of secondary standards assembled using wire mesh or glass plate of known transmittance is found as a better alternative for analysing heavy water, especially on routine basis. The paper describes this methodology. (author)

  13. The Consortium for Advanced Simulation of Light Water Reactors

    International Nuclear Information System (INIS)

    The Consortium for Advanced Simulation of Light Water Reactors (CASL) is a DOE Energy Innovation Hub for modeling and simulation of nuclear reactors. It brings together an exceptionally capable team from national labs, industry and academia that will apply existing modeling and simulation capabilities and develop advanced capabilities to create a usable environment for predictive simulation of light water reactors (LWRs). This environment, designated as the Virtual Environment for Reactor Applications (VERA), will incorporate science-based models, state-of-the-art numerical methods, modern computational science and engineering practices, and uncertainty quantification (UQ) and validation against data from operating pressurized water reactors (PWRs). It will couple state-of-the-art fuel performance, neutronics, thermal-hydraulics (T-H), and structural models with existing tools for systems and safety analysis and will be designed for implementation on both today's leadership-class computers and the advanced architecture platforms now under development by the DOE. CASL focuses on a set of challenge problems such as CRUD induced power shift and localized corrosion, grid-to-rod fretting fuel failures, pellet clad interaction, fuel assembly distortion, etc. that encompass the key phenomena limiting the performance of PWRs. It is expected that much of the capability developed will be applicable to other types of reactors. CASL's mission is to develop and apply modeling and simulation capabilities to address three critical areas of performance for nuclear power plants: (1) reduce capital and operating costs per unit energy by enabling power uprates and plant lifetime extension, (2) reduce nuclear waste volume generated by enabling higher fuel burnup, and (3) enhance nuclear safety by enabling high-fidelity predictive capability for component performance.

  14. The Consortium for Advanced Simulation of Light Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ronaldo Szilard; Hongbin Zhang; Doug Kothe; Paul Turinsky

    2011-10-01

    The Consortium for Advanced Simulation of Light Water Reactors (CASL) is a DOE Energy Innovation Hub for modeling and simulation of nuclear reactors. It brings together an exceptionally capable team from national labs, industry and academia that will apply existing modeling and simulation capabilities and develop advanced capabilities to create a usable environment for predictive simulation of light water reactors (LWRs). This environment, designated as the Virtual Environment for Reactor Applications (VERA), will incorporate science-based models, state-of-the-art numerical methods, modern computational science and engineering practices, and uncertainty quantification (UQ) and validation against data from operating pressurized water reactors (PWRs). It will couple state-of-the-art fuel performance, neutronics, thermal-hydraulics (T-H), and structural models with existing tools for systems and safety analysis and will be designed for implementation on both today's leadership-class computers and the advanced architecture platforms now under development by the DOE. CASL focuses on a set of challenge problems such as CRUD induced power shift and localized corrosion, grid-to-rod fretting fuel failures, pellet clad interaction, fuel assembly distortion, etc. that encompass the key phenomena limiting the performance of PWRs. It is expected that much of the capability developed will be applicable to other types of reactors. CASL's mission is to develop and apply modeling and simulation capabilities to address three critical areas of performance for nuclear power plants: (1) reduce capital and operating costs per unit energy by enabling power uprates and plant lifetime extension, (2) reduce nuclear waste volume generated by enabling higher fuel burnup, and (3) enhance nuclear safety by enabling high-fidelity predictive capability for component performance.

  15. Heavy metal complexes with organic ligands from surface waters of the uranium mining area in Ronneburg, Thuringia

    International Nuclear Information System (INIS)

    The study focussed on nickel and uranium. A method based on size exclusion chromatography was developed to isolate heavy metals complexed with organic ligands. The compounds and complexes present in the surface waters were characterized. (P.A.)

  16. High-conversion and high-burnup core concepts for pressure-tube-type heavy water reactors

    International Nuclear Information System (INIS)

    A high-conversion and a high-burnup core concept for a pressure-tube-type heavy water reactor are presented and analyzed from the standpoint of neutronics. These core concepts are based on the fact that neutron spectrum can be shifted by adjusting the amount of heavy water moderator outside the pressure tubes without affecting core-cooling capability. For the high-conversion core, where the heavy water moderator is replaced by a gas such as CO2 [carbon dioxide], a conversion ratio of more than 0.8 and an average discharge fuel burnup of 50GWd/t have been estimated to be attained with standard design fuel assemblies having 7.5% fissile Pu enrichment. For the high-burnup core, where fuel assemblies burned in the high-conversion (gas) region are relocated into the burner (heavy water) region, an average discharge fuel burnup of 110GWd/t has been estimated

  17. Red cabbage yield, heavy metal content, water use and soil chemical characteristics under wastewater irrigation.

    Science.gov (United States)

    Tunc, Talip; Sahin, Ustun

    2016-04-01

    The objective of this 2-year field study was to evaluate the effects of drip irrigation with urban wastewaters reclaimed using primary (filtration) and secondary (filtration and aeration) processes on red cabbage growth and fresh yield, heavy metal content, water use and efficiency and soil chemical properties. Filtered wastewater (WW1), filtered and aerated wastewater (WW2), freshwater and filtered wastewater mix (1:1 by volume) (WW3) and freshwater (FW) were investigated as irrigation water treatments. Crop evapotranspiration decreased significantly, while water use efficiency increased under wastewater treatments compared to FW. WW1 treatment had the lowest value (474.2 mm), while FW treatments had the highest value (556.7 mm). The highest water use efficiency was found in the WW1 treatment as 8.41 kg m(-3), and there was a twofold increase with regard to the FW. Wastewater irrigation increased soil fertility and therefore red cabbage yield. WW2 treatment produced the highest total fresh yield (40.02 Mg ha(-1)). However, wastewater irrigation increased the heavy metal content in crops and soil. Cd content in red cabbage heads was above the safe limit, and WW1 treatment had the highest value (0.168 mg kg(-1)). WW3 treatment among wastewater treatments is less risky in terms of soil and crop heavy metal pollution and faecal coliform contamination. Therefore, WW3 wastewater irrigation for red cabbage could be recommended for higher yield and water efficiency with regard to freshwater irrigation. PMID:26611631

  18. Nonlinear dynamics of rotating shallow water methods and advances

    CERN Document Server

    Zeitlin, Vladimir

    2007-01-01

    The rotating shallow water (RSW) model is of wide use as a conceptual tool in geophysical fluid dynamics (GFD), because, in spite of its simplicity, it contains all essential ingredients of atmosphere and ocean dynamics at the synoptic scale, especially in its two- (or multi-) layer version. The book describes recent advances in understanding (in the framework of RSW and related models) of some fundamental GFD problems, such as existence of the slow manifold, dynamical splitting of fast (inertia-gravity waves) and slow (vortices, Rossby waves) motions, nonlinear geostrophic adjustment and wa

  19. Digital control application for the advanced boiling water reactor

    International Nuclear Information System (INIS)

    The Advanced Boiling Water Reactor (ABWR) is a 1300 MWe class Nuclear Power Plant whose design studies and demonstration tests are being performed by the three manufacturers, General Electric, Toshiba and Hitachi, under requirement specifications from the Tokyo Electric Power Company. The goals are to apply new technology to the BWR in order to achieve enhanced operational efficiencies, improved safety measures and cost reductions. In the plant instrumentation and control areas, traditional analog control equipment and wire cables will be replaced by distributed digital microprocessor based control units communicating with each other and the control room over fiber optic multiplexed data buses

  20. Reflector modeling in advanced nodal analysis of pressurized water reactors

    International Nuclear Information System (INIS)

    Recent progress in the modeling of the reflector regions of pressurized water reactors within the framework of advanced nodal diffusion analysis methods is reviewed. Attention is focused on the modeling of the radial reflector of a PWR which is most problematic because of its irregular and heterogeneous structure. Numerical results are presented to demonstrate the high accuracy of the methods which are now available for generating nodal reflector parameters and it is shown that errors due to reflector modeling in multi-dimensional nodal reactor analysis can be practically eliminated. (author). 23 refs, 1 fig., 2 tabs

  1. Advanced fuels for plutonium management in pressurized water reactors

    International Nuclear Information System (INIS)

    Several fuel concepts are under investigation at CEA with the aim of manage plutonium inventories in pressurized water reactors. This options range from the use of mature technologies like MOX adapted in the case of MOX-EUS (enriched uranium support) and COmbustible Recyclage A ILot (CORAIL) assemblies to more innovative technologies using IMF like DUPLEX and advanced plutonium assembly (APA). The plutonium burning performances reported to the electrical production go from 7 to 60 kg (TW h)-1. More detailed analysis covering economic, sustainability, reliability and safety aspects and their integration in the whole fuel cycle would allow identifying the best candidate

  2. Heavy metals in a degraded soil treated with sludge from water treatment plant

    Directory of Open Access Journals (Sweden)

    Teixeira Sandra Tereza

    2005-01-01

    Full Text Available The application of water treatment sludge (WTS to degraded soil is an alternative for both residue disposal and degraded soil reclaim. This study evaluated effects of the application of water treatment sludge to a Typic Hapludox soil degraded by tin mining in the National Forest of Jamari, State of Rondonia, Brazil, on the content of heavy metals. A completely randomized experimental design with five treatments was used: control (n = 4; chemical control, which received only liming (n = 4; and rates D100, D150 and D200, which corresponded to 100, 150 and 200 mg of N-sludge kg-1 soil (n = 20, respectively. Thirty days after liming, period in which soil moisture was kept at 70% of the retention capacity, soil samples were taken and analyzed for total and extractable Fe, Cu, Mn, Zn, Cd, Pb, Ni, and Cr. The application of WTS increased heavy-metal contents in the degraded soil. Although heavy metals were below their respective critical limits, sludge application onto degraded areas may cause hazardous environmental impact and thus must be monitored.

  3. Water plasmas for the revalorisation of heavy oils and cokes from petroleum refining.

    Science.gov (United States)

    Hueso, José L; Rico, Víctor J; Cotrino, José; Jiménez-Mateos, J M; González-Elipe, Agustín R

    2009-04-01

    This work investigates the possibility of using plasmas to treat high boiling point and viscous liquids (HBPVL) and cokes resulting as secondary streams from the refining of oil. For their revalorisation, the use of microwave (MW) induced plasmas of water is proposed, as an alternative to more conventional processes (i.e., catalysis, pyrolysis, combustion, etc.). As a main result, this type of energetic cold plasma facilitates the conversion at room temperature of the heavy aromatic oils and cokes into linear hydrocarbons and synthesis gas, commonly defined as syngas (CO + H2 gas mixture). The exposure of the coke to this plasma also facilitates the removal of the sulfur present in the samples and leads to the formation on their surface of a sort of carbon fibers and rods network and new porous structures. Besides, optical emission measurements have provided direct evidence of the intermediates resulting from the fragmentation of the heavy oils and cokes during their exposure to the water plasma. Furthermore, the analysis of the mass spectra patterns suggests a major easiness to break the aromatic bonds mainly contained in the heavy oils. Therefore, an innovative method for the conversion of low value residues from oil-refining processes is addressed. PMID:19452916

  4. Irrigation water quality in southern Mexico City based on bacterial and heavy metal analyses

    Energy Technology Data Exchange (ETDEWEB)

    Solis, C. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Apdo Postal 20-364, 01000 Mexico, DF (Mexico)]. E-mail: corina@fisica.unam.mx; Sandoval, J. [Instituto de Ecologia, Universidad Nacional Autonoma de Mexico, Apdo Postal 70-275, 04510 Mexico, DF (Mexico); Perez-Vega, H. [Ciencias Agropecuarias, Universidad Juarez Autonoma de Tabasco, Ave. Universidad S/N. Zona de la Cultura, 86040 Villa Hermosa, Tabasco (Mexico); Mazari-Hiriart, M. [Instituto de Ecologia, Universidad Nacional Autonoma de Mexico, Apdo Postal 70-275, 04510 Mexico, DF (Mexico)

    2006-08-15

    Xochimilco is located in southern Mexico City and represents the reminiscence of the pre-Columbian farming system, the 'chinampa' agriculture. 'Chinampas' are island plots surrounded by a canal network. At present the area is densely urbanized and populated, with various contaminant sources contributing to the water quality degradation. The canal system is recharged by a combination of treated-untreated wastewater, and precipitation during the rainy season. Over 40 agricultural species, including vegetables, cereals and flowers, are produced in the 'chinampas'. In order to characterize the quality of Xochimilcos' water used for irrigation, spatial and temporal contaminant indicators such as microorganisms and heavy metals were investigated. Bacterial indicators (fecal coliforms, fecal enterococcus) were analyzed by standard analytical procedures, and heavy metals (such as Fe, Cu, Zn and Pb) were analyzed by particle induced X-ray emission (PIXE). The more contaminated sites coincide with the heavily populated areas. Seasonal variation of contaminants was observed, with the higher bacterial counts and heavy metal concentrations reported during the rainy season.

  5. Irrigation water quality in southern Mexico City based on bacterial and heavy metal analyses

    International Nuclear Information System (INIS)

    Xochimilco is located in southern Mexico City and represents the reminiscence of the pre-Columbian farming system, the 'chinampa' agriculture. 'Chinampas' are island plots surrounded by a canal network. At present the area is densely urbanized and populated, with various contaminant sources contributing to the water quality degradation. The canal system is recharged by a combination of treated-untreated wastewater, and precipitation during the rainy season. Over 40 agricultural species, including vegetables, cereals and flowers, are produced in the 'chinampas'. In order to characterize the quality of Xochimilcos' water used for irrigation, spatial and temporal contaminant indicators such as microorganisms and heavy metals were investigated. Bacterial indicators (fecal coliforms, fecal enterococcus) were analyzed by standard analytical procedures, and heavy metals (such as Fe, Cu, Zn and Pb) were analyzed by particle induced X-ray emission (PIXE). The more contaminated sites coincide with the heavily populated areas. Seasonal variation of contaminants was observed, with the higher bacterial counts and heavy metal concentrations reported during the rainy season

  6. INFLUENCE OF HEAVY METALS HYDROXIDES ON WATER DISSOCIATION IN BIPOLAR MEMBRANE

    Directory of Open Access Journals (Sweden)

    Sheldeshov N. V.

    2015-12-01

    Full Text Available The results of study of bipolar membrane – analogue of MB-2, modified with chemically introduced chromium (III, iron (III and nickel (II hydroxides by the method of frequency spectrum of electrochemical impedance, by infrared spectroscopy and scanning electron microscopy in combination with X-ray spectrum analysis are presented. It is shown, that sequential treatment of cation-exchanger, contained in cationexchange membrane, with metal salt solution and alkali solution does not result in formation of complex compounds of these metals with ionic groups of ion exchanger. It was found that in these conditions the presence of heavy metals in the phase of cationexchanger confirmed by X-ray analysis, however, crystals of hydroxides of heavy metals are not detected in the size range of 1000 nm to 20 nm. These heavy metal compounds are thermally unstable and their catalytic activity in the reaction of dissociation of water molecules decreases with increasing temperature during heat treatment. The introduction of low-soluble hydroxides of d-metals (chromium (III, iron (III, nickel(II by chemical method can significantly improve the electrochemical characteristics of a bipolar membrane. The most effective catalysts in water dissociation reaction are the hydroxides of chromium (III and iron (III and, as a consequence, membranes with these hydroxides have a lower value of overpotential compared with original membrane at the same current density

  7. Physico-Chemical Characteristics and Heavy Metal Contents of Water from Karavasta lagoon, Albania

    Directory of Open Access Journals (Sweden)

    ROMINA KOTO

    2014-09-01

    Full Text Available A study was conducted on physico-chemical parameters and heavy metal contents of water from the Karavasta Lagoon(40º56’ N and 19º29’ E. Karavasta Lagoon is one of the largest lagoons in the Mediterranean Seaand one of the most important economic and ecological areas in the southern part of Albania. The overall complex is composed of four lagoons, sand dunes, and a river mouth has a surface of 10000 ha. It is situated in the central part of western region, between Shkumbini River in the north and Semani River in the south, 40 km west of the city of Lushnja, by the Adriatic coast. The study aimed to determine (i the water quality in the lagoon of Karavasta using physico-chemical parameters and the level of heavy metals, (2 its status to support living life in the aquatic ecosystem. Data on temperature, pH, salinity, dissolved oxygen were obtained in-situ using Hanna multi-parameters instruments. Surface water of the lagoon was analyzed for heavy metals: Pb, Cr, Cu, Cd, As.The results showed that water temperature varies depending on the seasons. The highest temperatures were in July from 26 to 28.6 ºC depending on the sampling station.The results showed that water temperature varies depending on the seasons. Highest values of pH in the water of the lagoon are verified in December from 10.72 to11.98. The values of salinity in the lagoon of Karavasta are higher in Dajlani station SS1 ranging 42.31% in July to 40.83 %in December, depending from the connection with Adriatic Sea. Also it varies considerably from one area to another, and between seasons, depending on the degree of isolationThe heavy metals Cr, Pb, Cu in some stations are found to be close or higher than the values allowed by the EU and pose a potential health risk to humans and the aquatic life of the lagoon’s ecosystem.

  8. Electrochemical sensors and devices for heavy metals assay in water: the French groups' contribution

    Directory of Open Access Journals (Sweden)

    Luca ePUJOL

    2014-04-01

    Full Text Available A great challenge in the area of heavy metal trace detection is the development of electrochemical techniques and devices which are user-friendly, robust, selective, with low detection limits and allowing fast analyses. This review presents the major contribution of the French scientific academic community in the field of electrochemical sensors and electroanalytical methods within the last 20 years. From the well-known polarography to the up-to-date generation of functionalized interfaces, the different strategies dedicated to analytical performances improvement are exposed: stripping voltammetry, solid mercury-free electrode, ion selective sensor, carbon based materials, chemically modified electrodes, nano-structured surfaces. The paper particularly emphasizes their advantages and limits face to the last Water Frame Directive devoted to the Environmental Quality Standards for heavy metals. Recent trends on trace metal speciation as well as on automatic on line monitoring devices are also evoked.

  9. In-air PIXE for analyzing heavy metals in water boiled in pans

    International Nuclear Information System (INIS)

    The release rates of heavy metals from pans were measured for boiling water as well as for an acidic solution prior to an investigation on the release or sorption of trace elements due to cooking of food by boiling. The boiled samples were condensed and analyzed by means of in-air PIXE. The release of heavy metals was measured for five kinds of pans. For all pans the release rates were considerably more increased by boiling of a 5% solution of acetic acid. Furthermore it was found that by using the alumina coated aluminum pan (alumina pan) the respective release rates of Fe, Cu and Zn were all less than 50 μg per 100 cm2 of the pan surface dipped in the solution, and that monitoring of the contents of aluminum in the boiled solution enabled the estimation of the contribution of metal elements from the pan wall. (orig.)

  10. Composition of Heavy Metals in the Water of the River Lopota and Floating Silt

    Directory of Open Access Journals (Sweden)

    Tea Mchedluri

    2014-05-01

    Full Text Available Like other small rivers in Georgia, the river Lopota, which is one of the most important left tributaries of the river Alazani, is ecologically less studied. Although, phosphorus - potassium fertilizers containing heavy metals from agricultural lands, leaching sediment , composts made of municipal and household waste are systematically leached into the river Lopota, the composition of heavy metals, copper, zinc, iron, lead, nickel, manganese is lower than it is accepted. This fact is promoted by water pH, under which these metals are hydrolyzed and their main mass is accumulated at the bottom, and the rest of it is absorbed in the floating silt. Therefore, they cannot have a negative impact on self-scouring and ecological condition of the river.

  11. Electrochemical sensors and devices for heavy metals assay in water: the French groups' contribution

    Science.gov (United States)

    Pujol, Luca; Evrard, David; Groenen-Serrano, Karine; Freyssinier, Mathilde; Ruffien-Ciszak, Audrey; Gros, Pierre

    2014-04-01

    A great challenge in the area of heavy metal trace detection is the development of electrochemical techniques and devices which are user-friendly, robust, selective, with low detection limits and allowing fast analyses. This review presents the major contribution of the French scientific academic community in the field of electrochemical sensors and electroanalytical methods within the last 20 years. From the well-known polarography to the up-to-date generation of functionalized interfaces, the different strategies dedicated to analytical performances improvement are exposed: stripping voltammetry, solid mercury-free electrode, ion selective sensor, carbon based materials, chemically modified electrodes, nano-structured surfaces. The paper particularly emphasizes their advantages and limits face to the last Water Frame Directive devoted to the Environmental Quality Standards for heavy metals. Recent trends on trace metal speciation as well as on automatic “on line” monitoring devices are also evoked.

  12. Fast removal of heavy metal ions and phytic acids from water using new modified chelating fiber

    Institute of Scientific and Technical Information of China (English)

    Li Xu; Jin Nan Wang; Ying Meng; Ai Min Li

    2012-01-01

    The graft copolymerization of acrylic acid (AA) onto polyethylene glycol terephthalate (PET) fiber initiated by benzoy peroxide (BPO) was carried out in heterogeneous media.Moreover,modification of the grafted PET fiber (PET-AA) was done by changing the carboxyl group into acylamino group through the reaction with dimethylamine.The modified chelating fiber (NDWJN 1) was characterized using elementary analysis,SEM and FT-IR spectroscopy.Adsorption kinetic curves indicated that NDWJN1 could fast remove heavy metal ions and phytic acids from water effectively.Furthermore,batch kinetic studies indicated that heavy metal ions adsorbed to NDWJN1 could be fitted well by both pseudo-first-order and pseudo-second-order adsorption equations,but the intra-particle diffusion plaved a dominant role in the adsorption of phvtic acids.

  13. [Study on measurement of trace heavy metal Ni in water by laser induced breakdown spectroscopy technique].

    Science.gov (United States)

    Shi, Huan; Zhao, Nan-jing; Wang, Chun-long; Lu, Cui-ping; Liu, Li-tuo; Chen, Dong; Ma, Ming-jun; Zhang, Yu-jun; Liu, Jian-guo; Liu, Wen-qing

    2012-01-01

    The spectroscopy emission characteristics and the detection limit of trace heavy metal nickel in water was studied based on laser induced breakdown spectroscopy technique, with a 1,064 nm wavelength Nd : YAG laser as excitation source, and the echelle spectrometer and ICCD detector were used for spectral separation and high sensitive detection with high resolution and wide spectral range. A round flat solid state graphite as matrix was used for element enrichment for reducing water splashing, extending the plasma lifetime and improving the detection sensitivity, and the experimental sample was prepared by titrating a fixed volume of nickel nitrate solution of different concentrations on a fixed area of the graphite matrix. The results show that the better detection delay time is about 700 ns, the spectrum intensity raises with the concentration increase, a good linear relationship is presented at low concentration with a correlation coefficient 0.996 1, and the lower limit of detection of nickel in water with 0.28 mg x L(-1) was retrieved. A measurement method for further study of trace heavy metals in water is provided with laser induced breakdown spectroscopy technique. PMID:22497119

  14. Reactive liquid/liquid extraction of heavy metals from landfill seepage waters. Its characterisation and application

    International Nuclear Information System (INIS)

    This study demonstrates the applicability of liquid-liquid extraction by means of the commercial complexers LIX26R and LIX84R to heavy metal removal from waste waters. The composition of this oil-soluble complex is MeR2, where Me denotes Hg2+, Cd2+, Zn2+, Cu2+, and Ni2+, and R denotes LIX84R. This composition makes the complex electrically neutral, and all polar groups are located inside the molecule. The extraction efficiency of the complexer LIX84R for the various metal ions is evident in the succession Cu2+, Ni2+ >> Zn2+ > Hg2+ > Cd2+. These heavy metal ions are even readily extractable at chloride concentrations of up to 1 mol/l. As the structure of the complexer is that of an oil-soluble surfactant with complexing properties, it accumulates at the phase boundary between oil and water. Measurement of interfacial tension in various solvent systems showed that the polar solvent chloroform permits only a weak accumulation of the complexer (400 nmol/m2), whereas the unpolar solvent kerosine permits greater accumulation specifically on the water side of the phase boundary (1958 nmol/m2). Organic solvents solvate the complexer so well, that it is even removed from the air side of the phase boundary. The differing accumulation of the complexer at the water/oil phase boundary explains the differing increase of phase separation time for polar and unpolar solvents. (orig.)

  15. [New methodology for heavy metals measurement in water samples by PGNAA-XRF].

    Science.gov (United States)

    Jia, Wen-Bao; Zhang, Yan; Hei, Da-Qian; Ling, Yong-Sheng; Shan, Qing; Cheng, Can

    2014-11-01

    In the present paper, a new combined detection method was proposed using prompt gamma neutron activation analysis (PGNAA) and characteristic X-ray fluorescence to improve the heavy metals measurement accuracy for in-situ environmental water rejects analysis by PGNAA technology. Especially, the characteristic X-ray fluorescence (XRF) of heavy metals is induced by prompt gamma-ray directly instead of the traditional excitation sources. Thus, a combined measurement facility with an 241 AmBe neutron source, a BGO detector and a NaI-Be detector was developed to analyze the pollutants in water. The two detectors were respectively used to record prompt gamma-ray and characteristic X-ray fluorescence of heavy metals. The prompt gamma-ray intensity (I(γ)) and characteristic X-ray fluorescence intensity (I(x)) was determined by MCNP calculations for different concentration (c(i)) of chromium (Cr), cadmium (Cd), mercury (Hg) and lead (Pb), respectively. The simulation results showed that there was a good linear relationship between I(γ), I(x) and (c(i)), respectively. The empirical formula of combined detection method was given based on the above calculations. It was found that the combined detection method was more sensitive for high atomic number heavy metals like Hg and Pb measurement than low atomic number like Cr and Cd by comparing and analyzing I(γ) and I(x). The limits of detection for Hg and Pb by the combined measurement instrument were 17.4 and 24.2 mg x kg(-1), respectively. PMID:25752071

  16. Physico chemical characteristics and heavy metal contents of water from Butrinti lagoon, Albania

    Directory of Open Access Journals (Sweden)

    Teuta Topi

    2013-05-01

    Full Text Available A study was conducted between May 2010 and January 20011 in the Butrinti Lagoon, an important ecological and economical area in the south of Albania. The study aimed to determine (i the water quality in the lagoon of Butrint using physico-chemical parameters and level of heavy metals, (2 its status to support living life in the aquatic ecosystem. Data on temperature, pH, salinity, dissolved oxygen, EC were obtained in - situ using multiparameter portable instrument. Surface and bottom water of the lagoon were analyzed for heavy metals: Pb, Cr, Cu, Cd, Hg. The results showed that water temperature varies depending on the seasons. The highest temperatures were in August from 26 to 27.3 0C depending on the sampling station. pH in the water of the lagoon is basic, its values ranged from 8.12 to 8.49, and were optimal for the production of mussels. The values of salinity in the lagoon of Butrint are smaller than those of the Ionian sea influenced by rivers Bistrica, Pavlo and groundwater resources. Lower values of DO in the depth of the lagoon were recorded in August at stations SS2 (1.4 mg L-1 and SS5 (1.9 mg L-1, and therefore a damage was noticed in the growth of mussels in the lagoon. The heavy metals Cr, Pb, in some stations are found in higher levels than the values allowed by the EU and pose a potential health risk to humans and the aquatic life of the lagoon’s ecosystem.

  17. Modern technologies and equipment for environment and sustainable development at ROMAG-PROD Heavy Water Plant

    International Nuclear Information System (INIS)

    At ROMAG-PROD Heavy Water Plant, the sustainable development concept incorporates as a priority the environmental protection through the production process technology. Norway's Prime Minister, Mr. Gro Harlem Brundtland used the concept of 'sustainable development' in 1987, when as President of International Commission for Environment and Sustainable Development, he presented his report 'Our common future'. Sustainable development means that development that allows satisfying our present needs without spoiling the next generation capacity to meet their own needs. Any technology has both advantages and disadvantages; when considering the concept of sustainable development we have to take into account all the aspects, namely: - causes identification and review; - results evaluation; - corrective and preventive actions. Thus, ROMAG-PROD Heavy Water Plant has implemented a typical environment management system by means of what the general and specific objectives have been established, these objectives being stated in an Environment Policy Declaration: - Environment Management System as per SR EN ISO 14001/1997; - Quality Management System as per SR EN ISO 9001/2000; - IQNet- The International Certification Network. The paper presents the modern equipment for emissions and in-missions management with real time data transmission, for air and water as environment elements. Section two deals with trial of modern technology for industrial discharged wastewater treatment using the method of controlled batching of surface-active materials. Investigations on method application and laboratory testing as well as findings are given. As a conclusion, one can state that ROMAG-PROD Heavy Water Plant, has as one of its main concern keeping on high standards the safety of its equipment operation, sustainable development and risk eliminating so that neither environment or the population in vicinity is affected. (authors)

  18. Development of an advanced water treatment system for wastewater reuse.

    Science.gov (United States)

    Chung, H; Ku, B; Gregory, J

    2008-09-01

    The aim of this research was to develop an optimal reuse system applying various types of advanced oxidation processes such as titanium dioxide (TiO2), ozone (O3) and electro-coagulation/oxidation methods. This system is suitable for improving the treatment efficiency of difficult wastewaters, and for the efficient reuse of wastewater. The connecting systems were divided into various types to investigate the stability and treatment efficiency according to the kinds of waste load. Different treatment sequences were examined taking into consideration the characteristics and economical efficiency. In the case of electro-coagulation/oxidation + ozone system, the mean treatment efficiency in terms of BOD5, CODCr and SS removal was 98.7%. The effluent concentration was 50.2 mg l(-1), 38.3 mg l(-1), 30.4 mg l(-1), respectively. In considering the economical efficiency and commercial use, around an eighth of the treatment expenses and around a fifth of the maintenance expenses could be saved compared with existing water treatment systems. The initial construction expenses could be reduced by a third to a fifth. Therefore, if a proper implementation of this research is carried out in relation to site conditions and the purpose of the water reuse, the water reuse rate will be higher and water resources can be protected. PMID:18844120

  19. Class III Mid-Term Project, "Increasing Heavy Oil Reserves in the Wilmington Oil Field Through Advanced Reservoir Characterization and Thermal Production Technologies"

    Energy Technology Data Exchange (ETDEWEB)

    Scott Hara

    2007-03-31

    The overall objective of this project was to increase heavy oil reserves in slope and basin clastic (SBC) reservoirs through the application of advanced reservoir characterization and thermal production technologies. The project involved improving thermal recovery techniques in the Tar Zone of Fault Blocks II-A and V (Tar II-A and Tar V) of the Wilmington Field in Los Angeles County, near Long Beach, California. A primary objective has been to transfer technology that can be applied in other heavy oil formations of the Wilmington Field and other SBC reservoirs, including those under waterflood. The first budget period addressed several producibility problems in the Tar II-A and Tar V thermal recovery operations that are common in SBC reservoirs. A few of the advanced technologies developed include a three-dimensional (3-D) deterministic geologic model, a 3-D deterministic thermal reservoir simulation model to aid in reservoir management and subsequent post-steamflood development work, and a detailed study on the geochemical interactions between the steam and the formation rocks and fluids. State of the art operational work included drilling and performing a pilot steam injection and production project via four new horizontal wells (2 producers and 2 injectors), implementing a hot water alternating steam (WAS) drive pilot in the existing steamflood area to improve thermal efficiency, installing a 2400-foot insulated, subsurface harbor channel crossing to supply steam to an island location, testing a novel alkaline steam completion technique to control well sanding problems, and starting on an advanced reservoir management system through computer-aided access to production and geologic data to integrate reservoir characterization, engineering, monitoring, and evaluation. The second budget period phase (BP2) continued to implement state-of-the-art operational work to optimize thermal recovery processes, improve well drilling and completion practices, and evaluate the

  20. Multi-functional electrospun nanofibres for advances in tissue regeneration, energy conversion & storage, and water treatment.

    Science.gov (United States)

    Peng, Shengjie; Jin, Guorui; Li, Linlin; Li, Kai; Srinivasan, Madhavi; Ramakrishna, Seeram; Chen, Jun

    2016-03-01

    Tissue regeneration, energy conversion & storage, and water treatment are some of the most critical challenges facing humanity in the 21st century. In order to address such challenges, one-dimensional (1D) materials are projected to play a key role in developing emerging solutions for the increasingly complex problems. Eletrospinning technology has been demonstrated to be a simple, versatile, and cost-effective method in fabricating a rich variety of materials with 1D nanostructures. These include polymers, composites, and inorganic materials with unique chemical and physical properties. In this tutorial review, we first give a brief introduction to electrospun materials with a special emphasis on the design, fabrication, and modification of 1D functional materials. Adopting the perspective of chemists and materials scientists, we then focus on the recent significant progress made in the domains of tissue regeneration (e.g., skin, nerve, heart and bone) and conversion & storage of clean energy (e.g., solar cells, fuel cells, batteries, and supercapacitors), where nanofibres have been used as active nanomaterials. Furthermore, this review's scope also includes the advances in the use of electrospun materials for the removal of heavy metal ions, organic pollutants, gas and bacteria in water treatment applications. Finally a conclusion and perspective is provided, in which we discuss the remaining challenges for 1D electrospun nanomaterials in tissue regeneration, energy conversion & storage, and water treatment. PMID:26727278

  1. Computer code for the analyses of reactivity initiated accident of heavy water moderated and cooled research reactor 'EUREKA-2D'

    International Nuclear Information System (INIS)

    Codes, such as EUREKA and EUREKA-2 have been developed to analyze the reactivity initiated accident for light water reactor. These codes could not be applied directly for the analyses of heavy water moderated and cooled research reactor which are different from light water reactor not only on operation condition but also on reactor kinetic constants. EUREKA-2D which is modified EUREKA-2 is a code for the analyses of reactivity initiated accident of heavy water research reactors. Following items are modified: 1) reactor kinetic constants. 2) thermodynamic properties of coolant. 3) heat transfer equations. The feature of EUREKA-2D and an example of analysis are described in this report. (author)

  2. The Influence of Industrial Waste on Pesticide and Heavy Metal Conetnts in Cipinang-Sunter River Water Jakarta

    International Nuclear Information System (INIS)

    The measurement of pesticide and heavy metal contents of river water in upperstream (around some factories), and downstream (housing area), along Cipinang-Sunter river Jakarta, on February-June 1996 had been done. The aim of the measurement was to get information about the influence of factories waste on pesticide and heavy metal contents in the Cipinang river water. Gas and liquid chromatographis were used to measure the pesticide content and X-ray fluorecence spectrometry was used to measure the heavy metals content. Result of the measurements showed that Cipinang river water has contained some organochlorin pesticides, i.e., BHC, a and b endosulfan, dieldrin, pp-DDE, and heavy metals, i.e., Ti, V, Cr, Fe, Ni, Cu, Zn, and Pb

  3. Sustainable development concept applied to the ROMAG-PROD Heavy Water Plant

    International Nuclear Information System (INIS)

    Implementing the environmental and quality management systems to the ROMAG-PROD Heavy Water Plant was effected in order to comply with the European legislation regarding the environmental protection. Our organization was preoccupied in demonstrating the performances and control of the environmental impact of the adopted policy and objectives. The following steps were performed: - refurbishing the water purification installation at the hydrogen sulfides preparation facility; - grouping of girdle sensors; - installing the central safety control room; - installing independent sensors on waste water tubing; - refurbishing the installations transporting and storing hydrogen sulfide; - personnel training. Underway are: - building an installation for dispersion of the clear from the pool to the Topolnita River and the hydrotechnical amelioration of the borders; - refurbishing the hydrogen sulfide centrifugal compressors; - implementing the study concerning sulfide reduction with tensioactive materials

  4. Participation of mangrove species in the heavy metals control of production waters: Preliminary evaluation

    International Nuclear Information System (INIS)

    Tree species of Mangrove were planted in an oil production flooded water area in order to study their efficiency as biological filters for controlling heavy metals in the water. The results indicate that the plants not only successfully adapted to the continental environment but also serve as excellent biological filters accumulating barium and chromium in their structure. This process allowed for a richer and renewed biological diversity in the area, which favored the reappearance of vegetal and animal species that had disappeared from the ecosystem. Based on the quantification of the metals accumulated by plants, it was found that these metals accumulate in different parts of the plant depending on the plant species regardless of the physicochemical characteristic of the water and the weather conditions. The plants accumulated up to 200 gm of barium in their root und stem. The Rizophora mangle species accumulated the greatest amounts of barium avicennia germinans showed the largest survival rates

  5. The Distribution of Heavy Element From Fish, Algae, Water and Sea Sediment In Lemahabang Muria Peninsula

    International Nuclear Information System (INIS)

    The analysis of heavy elements from fish, algae, water and sea sediments in Muria peninsula Jepara has been carried out using neutron activation analysis (NAA) method. Irradiation of sample was carried out for twelve hours with using Lazy Susan facility with neutron flux of 0.585x1011 n.cm-2 .S-1. Comparative mode of measurement was used for avoiding the effects of neutron flux parameters on the results. The result on analysis using gamma spectrometry with a Ge(Li) detector showed that there were 6 elements which observed. Those elements contained in algae, fish, water and sea sediment were Co, Sb, Sc, Fe, Cr and Cd. The highest element concentration found in sediment was Fe of 65.625 ± 3.12 % and the lowest was Co of 0.00256 ± 0.00045 μg/g for sea water. This method give precision and relative accuracy of < 10 % for all elements. (author)

  6. HEAVY METAL CONTAMINATIONS IN SAGAR LAKE AND DRINKING WATER SOURCES OF SAGAR CITY

    Directory of Open Access Journals (Sweden)

    Nahid Parveen

    2012-08-01

    Full Text Available There are various toxic elements present in our surroundings out of that the toxic heavy metals Pb,Cd, As, Se, Cr and Cu can cause several harms to human these metals enter in humans by water. The all kind ofwaste materials are thrown into natural water bodies in each city, this makes the all ground and natural watersources contaminated. The all six metals have determined by Atomic absorption spectrophotometer(AAS inselected water samples from Sagar Lake and dug wells, hand pumps, tube wells etc. during Jan.2009 to June 2010 inevery month the all most all sample have higher metal concentrations than their prescribed permissible limits byWHO.

  7. PIXE analysis of heavy metals in water samples from a mining area in Mongolia

    Energy Technology Data Exchange (ETDEWEB)

    Bolormaa, Oyuntsetseg [Department of Environment Science and Technology, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502 (Japan)]. E-mail: bolormaa@n.cc.titech.ac.jp; Baasansuren, Jamsranjav [Department of Environment Science and Technology, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502 (Japan); Kawasaki, Katsunori [Department of Physics, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8551 (Japan); Watanabe, Makiko [Department of Environment Science and Technology, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502 (Japan); Hattori, Toshiyuki [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8550 (Japan)

    2006-01-15

    The affect of mining activity on the environment has been long of public concern. The present paper deals with chemical analysis of the Boroo River water samples collected in mining area of Mongolia focusing the determination of heavy metal contents by particle induced X-ray emission (PIXE) technique. The samples were prepared by preconcentration method (water samples treated to form metal-dibenzyldithiocarbamate (DBDTC) complexes and collected on a nuclepore track-etch membrane filter) and irradiated by 2.5 MeV proton beam from the single-end type Van de Graaff accelerator. The accuracy of the results was proved by using certified river water samples. The total dispersions of experimental procedure were evaluated by variance analysis.

  8. Performance of Water Recirculation Loop Maintenance Components for the Advanced Spacesuit Water Membrane Evaporator

    Science.gov (United States)

    Rector, Tony; Peyton, Barbara M.; Steele, John W.; Makinen, Janice; Bue, Grant C.; Campbell, Colin

    2014-01-01

    Water loop maintenance components to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop have undergone a comparative performance evaluation with a second SWME water recirculation loop with no water quality maintenance. Results show the benefits of periodic water maintenance. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the evaluation of water recirculation maintenance components was to further enhance this advantage through the leveraging of fluid loop management lessons learned from the International Space Station (ISS). A bed design that was developed for a UTAS military application, and considered for a potential ISS application with the Urine Processor Assembly, provided a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance cycle included the use of a biocide delivery component developed for ISS to introduce a biocide in a microgravity compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.

  9. Recent technological advances in the application of nano-catalytic technology to the enhanced recovery and upgrading of bitumen and heavy oils

    Energy Technology Data Exchange (ETDEWEB)

    Pereira Almao, P. [Calgary Univ., AB (Canada). Schulich School of Engineering

    2013-11-01

    Advances in Nanotechnology, such as manufacturing of nano-catalysts allow the online (during processing) and on site production of nano-catalysts for heavy oils upgrading. These inventions have also facilitated the development of two lines of heavy oils upgrading processes that make use of nano-catalysts for producing upgraded oil: In Situ Upgrading and Field Upgrading. Producing chemical upgrading of heavy oils is achievable and economically viable at lower temperatures and lower pressures than used in most upgraders if the use of nano-catalysts were implemented. The spontaneity of thermal, steam and hydro processing reactions for converting the different chemical families of hydrocarbons present in the heaviest fractions of heavy oils and bitumen (HO-B) into lighter products was shown recently. Spontaneity was measured by the value of the change of free energy at low pressure. These undesirable paths are spontaneous and uncontrollable under thermal cracking conditions, and require providing years of residence time for intermolecular hydrogen redistribution to minimize olefins polymerization, if at all possible. Instead, hydroprocessing in the presence of hydrogen activating catalysts would create an abundance of hydrogen radicals impeding large molecules condensation and olefins proliferation. In Situ Upgrading: performs coupled Enhanced Oil Recovery with In Reservoir Upgrading via Hot Fluid Injection (HFI). The heat handling of this HFI process and the production of transportable oil with no need of diluent from the start of operation completes the originality of it. This technology uses heavy fractions separated from produced oil to reintroduce heat into the reservoir along with suspended nano-catalysts and hydrogen. These components react in the well bore and inside the reservoir to release more heat (hydroprocessing reactions are exothermic) producing light gases and volatile hydrocarbons that contribute to increase oil detachment from the rock resulting in

  10. Chemical drinking water quality in Ghana: Water costs and scope for advanced treatment

    International Nuclear Information System (INIS)

    To reduce child mortality and improve health in Ghana boreholes and wells are being installed across the country by the private sector, NGO's and the Ghanaian government. Water quality is not generally monitored once a water source has been improved. Water supplies were sampled across Ghana from mostly boreholes, wells and rivers as well as some piped water from the different regions and analysed for the chemical quality. Chemical water quality was found to exceed the WHO guidelines in 38% of samples, while pH varied from 3.7 to 8.9. Excess levels of nitrate (NO3-) were found in 21% of the samples, manganese (Mn) and fluoride (F-) in 11% and 6.7%, respectively. Heavy metals such as lead (Pb), arsenic (As) and uranium (U) were localised to mining areas. Elements without health based guideline values such as aluminium (Al, 95%) and chloride (Cl, 5.7%) were found above the provisional guideline value. Economic information was gathered to identify water costs and ability to pay. Capital costs of wells and boreholes are about Pounds 1200 and Pounds 3800 respectively. The majority of installation costs are generally paid by the government or NGO's, while the maintenance is expected to be covered by the community. At least 58% of the communities had a water payment system in place, either an annual fee/one-off fee or 'pay-as-you-fetch'. The annual fee was between Pounds 0.3-21, while the boreholes had a water collection fee of Pounds 0.07-0.7/m3, many wells were free. Interestingly, the most expensive water ( Pounds 2.9-3.5/m3) was brought by truck. Many groundwater sources were not used due to poor chemical water quality. Considering the cost of unsuccessful borehole development, the potential for integrating suitable water treatment into the capital and maintenance costs of water sources is discussed. Additionally, many sources were not in use due to lack of water capacity, equipment malfunction or lack of economic resources to repair and maintain equipment. Those

  11. Chemical drinking water quality in Ghana: Water costs and scope for advanced treatment

    Energy Technology Data Exchange (ETDEWEB)

    Rossiter, Helfrid M.A. [School of Engineering, The University of Edinburgh, Edinburgh, EH9 3JL (United Kingdom); Owusu, Peter A.; Awuah, Esi [Department of Civil Engineering, Kwame Nkrumah University of Science and Technology, Kumasi (Ghana); MacDonald, Alan M. [British Geological Survey, Murchison House, West Mains Road, Edinburgh, EH9 3LA (United Kingdom); Schaefer, Andrea I., E-mail: Andrea.Schaefer@ed.ac.uk [School of Engineering, The University of Edinburgh, Edinburgh, EH9 3JL (United Kingdom)

    2010-05-01

    To reduce child mortality and improve health in Ghana boreholes and wells are being installed across the country by the private sector, NGO's and the Ghanaian government. Water quality is not generally monitored once a water source has been improved. Water supplies were sampled across Ghana from mostly boreholes, wells and rivers as well as some piped water from the different regions and analysed for the chemical quality. Chemical water quality was found to exceed the WHO guidelines in 38% of samples, while pH varied from 3.7 to 8.9. Excess levels of nitrate (NO{sub 3}{sup -}) were found in 21% of the samples, manganese (Mn) and fluoride (F{sup -}) in 11% and 6.7%, respectively. Heavy metals such as lead (Pb), arsenic (As) and uranium (U) were localised to mining areas. Elements without health based guideline values such as aluminium (Al, 95%) and chloride (Cl, 5.7%) were found above the provisional guideline value. Economic information was gathered to identify water costs and ability to pay. Capital costs of wells and boreholes are about Pounds 1200 and Pounds 3800 respectively. The majority of installation costs are generally paid by the government or NGO's, while the maintenance is expected to be covered by the community. At least 58% of the communities had a water payment system in place, either an annual fee/one-off fee or 'pay-as-you-fetch'. The annual fee was between Pounds 0.3-21, while the boreholes had a water collection fee of Pounds 0.07-0.7/m{sup 3}, many wells were free. Interestingly, the most expensive water ( Pounds 2.9-3.5/m{sup 3}) was brought by truck. Many groundwater sources were not used due to poor chemical water quality. Considering the cost of unsuccessful borehole development, the potential for integrating suitable water treatment into the capital and maintenance costs of water sources is discussed. Additionally, many sources were not in use due to lack of water capacity, equipment malfunction or lack of economic

  12. Chemical problems in the waste stripper tower of a heavy water plant

    International Nuclear Information System (INIS)

    An attempt has been made to understand the deposition problem encountered in the waste stripper tower of a heavy water plant based on the water-hydrogen sulphide exchange process. Brucite and chrysotile have been found to account for about 55% of the total amount of deposits with the rest being pyrite. Deposit characterisation when looked in conjunction with the plant's process feed water chemistry has thrown light on the cause for this deposition. Based on this analysis, a recommendation to use only deionised water as process feed water has been implemented in the plant. Computation on the speciation of H2S (a) at high temperature, pH 4-7 (which corresponds to the actual situation in the waste stripper), and (b) at ambient temperature, pH8-9(which corresponds to the situation when the effluent water gets mixed with lake water) have shown that HS- existing at the lower outlet has no chance of getting converted to H2S. (author). 13 refs., 5 tabs., 2 figs

  13. Fluid (Air/Water) Cushion Transportation Technology for Emplacing Heavy Canisters into Horizontal Disposal Drifts

    International Nuclear Information System (INIS)

    The disposal of certain types of radioactive waste canisters in a deep repository involves handling and emplacement of very heavy loads. The weight of these particular canisters can be in the order of 20 to 50 metric tons. They generally have to be handled underground in openings that are not much larger than the canisters themselves as it is time consuming and expensive to excavate and backfill large openings in a repository. This therefore calls for the development of special technology that can meet the requirements for safe operation at an industrial scale in restrained operating spaces. Air/water cushion lifting systems are used world wide in the industry for moving heavy loads. However, until now the technology needed for emplacing heavy cylindrical radioactive waste packages in bored drifts (with narrow annular gaps) has not been previously developed or demonstrated. This paper describes the related R and D work carried out by ANDRA (for air cushion technology) and by SKB and Posiva (for water cushion technology) respectively, mainly within the framework of the European Commission (EC) funded Integrated Project called ESDRED (6. European Framework Programme). The background for both the air and the water cushion applications is presented. The specific characteristics of the two different emplacement concepts are also elaborated. Then the various phases of the Test Programmes (including the Prototype phases) are detailed and illustrated for the two lifting media. Conclusions are drawn for each system developed and evaluated. Finally, based on the R and D experience, improvements deemed necessary for an industrial application are listed. The tests performed so far have shown that the emplacement equipment developed is operating efficiently. However further tests are required to verify the availability and the reliability of the equipment over longer periods of time and to identify the modifications that would be needed for an industrial application in a

  14. Study of the developmental status and operational features of heavy water reactors. Final report

    International Nuclear Information System (INIS)

    The Canadian Heavy Water Reactor System, CANDU, and future plans for it as reported in a number of recent Canadian papers, are briefly reviewed. This has been done recognizing several leading observers of the nuclear industry suggest CANDU may represent a promising longer term route to nuclear fuel self sufficiency. It now appears that the concept is well established with a demonstrated performance comparable to the best LWR installations, but it presently has fuel utilization efficiency which is of the same order as that of the current LWRs. It should also be noted that CANDU is designed to a different set of safety and regulatory criteria; a point having potential for at least a second order economic significance to many non-Canadian markets. The feature of particular interest, however, is that the system is indicated by the Canadian Government Corporation-Atomic Energy of Canada Ltd.- to be capable of upgrading to a thermal near breeder. As such, this is a point of substantial import, given that system hardware is already proven, of demonstrated safety, reliability and economy, and one for which some supply industry capability is now in place. Remaining areas of uncertainty in the planned CANDU program are those related to the near breeder fuel cycle with its implied fuel processing and recycling requirements, the economics of future heavy water supply, and the actual demonstration of the physics of a unity converter/near breeder. It is noted that recently a variant of this LWBR using heavy water coolant, has been proposed by U.S. workers. Thus LWBR related efforts may be a more appropriate direction for U.S. investigations than a direct focus on CANDU itself. It is recommended that further investigation of such improved conversion developments for existing LWRs be conducted; they could represent a potential addition to the present U.S. program for a 100 percent LMFBR future

  15. Prototype CIRCE plant - industrial demonstration of heavy water production from reformed hydrogen source

    International Nuclear Information System (INIS)

    Heavy water (D20) production has been dominated by the Girdler-Sulphide (G-S) process, which suffers several intrinsic disadvantages that lead to high production costs. Processes based on hydrogen/water exchange have become more attractive with the development of proprietary wetproofed catalysts by AECL. One process that is synergistic with industrial hydrogen production by steam methane reforming (SMR), the Combined Industrial Reforming and Catalytic Exchange (CIRCE) process, offers the best prospect for commercialization. SMRs are common globally in the oil-upgrading and ammonia industries. To study the CIRCE process in detail, AECL, in collaboration with Air Liquide Canada, constructed a prototype CIRCE plant (PCP) in Hamilton, Ontario. The plant became fully operational in 2000 July and is expected to operate to at least late fall of 2002. To-date, plant operation has confirmed the adequacy of the design and the capability of enriching deuterium to produce heavy water without compromising hydrogen production. The proprietary wetproofed catalyst has performed as expected, both in activity and in robustness. (author)

  16. On the physicochemical states of heavy metals of very small amounts in river water

    International Nuclear Information System (INIS)

    The physicochemical existence states of the heavy metals in river water were experimentally studied, with radioactive nuclides as tracers. The experimental samples taken from Kamo-river in the city of Kyoto were filtered through a membrane filter of 0.45 μm pore diameter. The radioactive nuclides of heavy metal tracers were added into the sample water, and pH was adjusted to the given value with hydrochloric solution on the acidic side and with sodium hydroxide solution on the alkaline side. After two days aging, the radioactivity ratios of the sediments on membrane filters to that of total passed samples were measured. The variation in the course of time of the concentrations of ionic tracers dialysed with cellulose tubes (24 angstrom pore diameter) was traced until the equilibrium condition was reached. The radioactivity of the supernatant of 20 ml of sample water added with 0.5 g of anion or cation exchange resin, and the concentrations of tracers in the upper layer of liquid in a centrifuge were measured. The existing conditions of elements such as zinc, cadmium, cobalt, strontium-yttrium were examined. In conclusion, the adsorption of all nuclides on the membrane filters increased with the increase of pH, but the significant difference was not recognized owing to the pore diameter (1.2 μm - 0.05 μm) excepting some experimental results. (Iwakiri, K.)

  17. Heavy metals concentration in water and sediments of the Prut River lower sector

    Directory of Open Access Journals (Sweden)

    Matache M. L.

    2013-04-01

    Full Text Available A 120 km sector of the Prut River, Eastern Romania, was surveyed for the concentration of four heavy metals (Cd, Cu, Pb and Zn in water and sediments samples. The analysed sector is located on the border between Romania and Moldova and it is part of the Lower Prut Floodplain Natural Park. The most important steel-producing factory in Romania is located in the park vicinity. Four campaigns have been performed for water collection during different river regimes (both flooding and drought. The water quality is an essential condition for the wetland ecosystems within the park area and the aquatic biota they support, as trace elements bioaccumulation along the food webs might appear (David et al., 2012. Sediments can provide useful information regarding mid- and long-term pollution of the aquatic bodies, being capable of sequestering and releasing important amounts of heavy metals depending on the river regime and extreme situations (van Gestel, 2008; Verhoeven, 2009. For the sediments samples, there is an ascendant trend from upstream to the junction with the Danube River, as the distance to the main urban pole approaches, consequence of a strong human insertion. Romanian standards were used for comparison (MEWM, 2006.

  18. Heavy metal content of alfalfa irrigated with waste and tubewell water

    Directory of Open Access Journals (Sweden)

    Mohammad Jamal Khan

    2011-11-01

    Full Text Available A field experiment was conducted to study the effect of wastewater on yield and heavy metal uptake of alfalfa along with a tubewell irrigated crop as control at the Agricultural University Peshawar during 2009. The experiment was conducted in small plots (2 x 1m replicated thrice with fertilizer additions. The crop was either irrigated with Hayatabad Industrial Estate (HIE wastewater or tubewell water. The yield data revealed that shoot dry weight was significantly affected by the irrigation water supplies and higher yield was recorded in wastewater irrigated plots and the increase was consistent with time (different cutting. By comparing the total dry biomass of the two treatments, it was observed that there was about 37% increase in yield over control with application of wastewater. The shoot dry weight increased by a factor of about two to three times from first cutting to third cutting in both the treatment plots and the magnitude of increase in yield was higher in wastewater irrigated plots. The heavy metal uptake by the crop was much higher in wastewater irrigated plots compared to tubewell water. The order of metal uptake was Fe> Mn>Zn>Cu>Pb>Ni>Cr>Cd. Shoot analysis showed no metal toxicity because the concentration of the metal was less than phytotoxic level and all the metals were within the permissible limits.

  19. Monitoring the H2S releases in heavy water production installations at ROMAG PROD

    International Nuclear Information System (INIS)

    The heavy water is obtained at ROMAG PROD heavy water plant by isotopic exchange in the water-hydrogen sulfide system. The hydrogen sulfide represents a potential polluting source due to its specific noxiousness because the gas is toxic, corrosive and explosive. The monitoring of hydrogen sulfide at ROMAG PROD is performed by a H2S sensor system which determines the concentration of H2S and other gases for 24 h/day. The analysis of H2S in the air is carried out in seven locations in residence and industrial areas. The Environment Protection Inspectorate - Mehedinti monitors the H2S concentration in the air in three locations in Drobeta Turnu Severin. The surveillance system processes the data from the H2S sensors by using a mathematical model able to design various scenarios for the toxic cloud dispersion. Following the H2S release evaluation at the site of ROMAG PROD supported also by the level II environment assessment worked out by CITON, Bucharest, the protection zone range was reduced from 1.3 km to 500 m, i.e., it was overlapped the industrial area. The ROMAG PROD is ISO 9001 and ISO 14001 certified since 2001

  20. Recent advances in high current vacuum arc ion sources for heavy ion fusion

    CERN Document Server

    Qi Nian Sheng; Prasad, R R; Krishnan, M S; Anders, A; Kwan, J; Brown, I

    2001-01-01

    For a heavy ion fusion induction linac driver, a source of heavy ions with charge states 1+-3+, approx 0.5 A current beams, approx 20 mu s pulse widths and approx 10 Hz repetition rates is required. Thermionic sources have been the workhorse for the Heavy Ion Fusion (HIF) program to date, but suffer from heating problems for large areas and contamination. They are limited to low (contact) ionization potential elements and offer relatively low ion fluxes with a charge state limited to 1+. Gas injection sources suffer from partial ionization and deleterious neutral gas effects. The above shortcomings of the thermionic ion sources can be overcome by a vacuum arc ion source. The vacuum arc ion source is a good candidate for HIF applications. It is capable of providing ions of various elements and different charge states in short and long pulse bursts and high beam current density. Under a Phase-I STTR from DOE, the feasibility of the vacuum arc ion source for the HIF applications was investigated. We have modifie...