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Sample records for chemical hydride slurry

  1. Chemical Hydride Slurry for Hydrogen Production and Storage

    Energy Technology Data Exchange (ETDEWEB)

    McClaine, Andrew W

    2008-09-30

    The purpose of this project was to investigate and evaluate the attractiveness of using a magnesium chemical hydride slurry as a hydrogen storage, delivery, and production medium for automobiles. To fully evaluate the potential for magnesium hydride slurry to act as a carrier of hydrogen, potential slurry compositions, potential hydrogen release techniques, and the processes (and their costs) that will be used to recycle the byproducts back to a high hydrogen content slurry were evaluated. A 75% MgH2 slurry was demonstrated, which was just short of the 76% goal. This slurry is pumpable and storable for months at a time at room temperature and pressure conditions and it has the consistency of paint. Two techniques were demonstrated for reacting the slurry with water to release hydrogen. The first technique was a continuous mixing process that was tested for several hours at a time and demonstrated operation without external heat addition. Further work will be required to reduce this design to a reliable, robust system. The second technique was a semi-continuous process. It was demonstrated on a 2 kWh scale. This system operated continuously and reliably for hours at a time, including starts and stops. This process could be readily reduced to practice for commercial applications. The processes and costs associated with recycling the byproducts of the water/slurry reaction were also evaluated. This included recovering and recycling the oils of the slurry, reforming the magnesium hydroxide and magnesium oxide byproduct to magnesium metal, hydriding the magnesium metal with hydrogen to form magnesium hydride, and preparing the slurry. We found that the SOM process, under development by Boston University, offers the lowest cost alternative for producing and recycling the slurry. Using the H2A framework, a total cost of production, delivery, and distribution of $4.50/kg of hydrogen delivered or $4.50/gge was determined. Experiments performed at Boston

  2. Combined on-board hydride slurry storage and reactor system and process for hydrogen-powered vehicles and devices

    Science.gov (United States)

    Brooks, Kriston P; Holladay, Jamelyn D; Simmons, Kevin L; Herling, Darrell R

    2014-11-18

    An on-board hydride storage system and process are described. The system includes a slurry storage system that includes a slurry reactor and a variable concentration slurry. In one preferred configuration, the storage system stores a slurry containing a hydride storage material in a carrier fluid at a first concentration of hydride solids. The slurry reactor receives the slurry containing a second concentration of the hydride storage material and releases hydrogen as a fuel to hydrogen-power devices and vehicles.

  3. Hydrogen transmission/storage with a metal hydride/organic slurry

    Energy Technology Data Exchange (ETDEWEB)

    Breault, R.W.; Rolfe, J.; McClaine, A. [Thermo Power Corp., Waltham, MA (United States)

    1998-08-01

    Thermo Power Corporation has developed a new approach for the production, transmission, and storage of hydrogen. In this approach, a chemical hydride slurry is used as the hydrogen carrier and storage media. The slurry protects the hydride from unanticipated contact with moisture in the air and makes the hydride pumpable. At the point of storage and use, a chemical hydride/water reaction is used to produce high-purity hydrogen. An essential feature of this approach is the recovery and recycle of the spent hydride at centralized processing plants, resulting in an overall low cost for hydrogen. This approach has two clear benefits: it greatly improves energy transmission and storage characteristics of hydrogen as a fuel, and it produces the hydrogen carrier efficiently and economically from a low cost carbon source. The preliminary economic analysis of the process indicates that hydrogen can be produced for $3.85 per million Btu based on a carbon cost of $1.42 per million Btu and a plant sized to serve a million cars per day. This compares to current costs of approximately $9.00 per million Btu to produce hydrogen from $3.00 per million Btu natural gas, and $25 per million Btu to produce hydrogen by electrolysis from $0.05 per Kwh electricity. The present standard for production of hydrogen from renewable energy is photovoltaic-electrolysis at $100 to $150 per million Btu.

  4. Predicting Hydride Donor Strength via Quantum Chemical Calculations of Hydride Transfer Activation Free Energy.

    Science.gov (United States)

    Alherz, Abdulaziz; Lim, Chern-Hooi; Hynes, James T; Musgrave, Charles B

    2018-01-25

    We propose a method to approximate the kinetic properties of hydride donor species by relating the nucleophilicity (N) of a hydride to the activation free energy ΔG ⧧ of its corresponding hydride transfer reaction. N is a kinetic parameter related to the hydride transfer rate constant that quantifies a nucleophilic hydridic species' tendency to donate. Our method estimates N using quantum chemical calculations to compute ΔG ⧧ for hydride transfers from hydride donors to CO 2 in solution. A linear correlation for each class of hydrides is then established between experimentally determined N values and the computationally predicted ΔG ⧧ ; this relationship can then be used to predict nucleophilicity for different hydride donors within each class. This approach is employed to determine N for four different classes of hydride donors: two organic (carbon-based and benzimidazole-based) and two inorganic (boron and silicon) hydride classes. We argue that silicon and boron hydrides are driven by the formation of the more stable Si-O or B-O bond. In contrast, the carbon-based hydrides considered herein are driven by the stability acquired upon rearomatization, a feature making these species of particular interest, because they both exhibit catalytic behavior and can be recycled.

  5. Physico-chemical principles of slurries

    Energy Technology Data Exchange (ETDEWEB)

    Leiber, C.O.

    1984-12-01

    Spectacular accidents have occurred in mining with products considered non-explosive. In view of the disastrous consequences of these accidents, the old 'Anfo' idea has been revived (= ammonium nitrate and fuel oil). Experiments in wet wells have led to the development of a new type of non-explosive blasting agents, i.e. the so-called slurries. Detonation of these slurries is divided into an energy release process and an energy conversion process. The basic mechanisms are described with a view to practical problems, e.g. detonation control, temperature dependence of the blasting characteristics, pressure dependence of the ignition process, critical diameter, slurry state problems, and sensitivity.

  6. Methane Fermentation of Slurry with Chemical and Biological Additive

    Directory of Open Access Journals (Sweden)

    Anna Smurzyńska

    2017-12-01

    Full Text Available The problem of proper slurry management is primarily present in intensive livestock production. Industrialized livestock farms generate enormous quantities of manure droppings in a livestock-litter-free system. The traditional management of slurry is made by using it as a fertilizer. Alternative techniques used for neutralizing the detrimental effect of slurry are based on the use of chemical and biological additives, as well as by introducing aerobic environment through aerobic or anaerobic digestion, leading to methane fermentation. In the experiment, cattle manure was used, which came from the Przybroda farm belonging to the University of Life Sciences in Poznan. The aim of the study was to determine the biogas yield of slurry using the chemical and biological additive available on the Polish market. Mesophilic and thermophilic fermentation was used for the indication of the effectiveness of the employed fermentation process. The slurry was supplemented by a biological and chemical additive, i.e. effective microorganisms and – PRP, respectively. The experiment allowed to achieve a higher biogas yield during the use of effective microorganisms.

  7. Mechanochemical synthesis of nanostructured chemical hydrides in hydrogen alloying mills

    International Nuclear Information System (INIS)

    Wronski, Z.; Varin, R.A.; Chiu, C.; Czujko, T.; Calka, A.

    2007-01-01

    Mechanical alloying of magnesium metal powders with hydrogen in specialized hydrogen ball mills can be used as a direct route for mechanochemical synthesis of emerging chemical hydrides and hydride mixtures for advanced solid-state hydrogen storage. In the 2Mg-Fe system, we have successfully synthesized the ternary complex hydride Mg 2 FeH 6 in a mixture with nanometric Fe particles. The mixture of complex magnesium-iron hydride and nano-iron released 3-4 wt.%H 2 in a thermally programmed desorption experiment at the range 285-295 o C. Milling of the Mg-2Al powder mixture revealed a strong competition between formation of the Al(Mg) solid solution and the β-MgH 2 hydride. The former decomposes upon longer milling as the Mg atoms react with hydrogen to form the hydride phase, and drive the Al out of the solid solution. The mixture of magnesium dihydride and nano-aluminum released 2.1 wt.%H 2 in the temperature range 329-340 o C in the differential scanning calorimetry experiment. The formation of MgH 2 was suppressed in the Mg-B system; instead, a hydrogenated amorphous phase (Mg,B)H x , was formed in a mixture with nanometric MgB 2 . Annealing of the hydrogen-stabilized amorphous mixture produced crystalline MgB 2

  8. Advanced chemical hydride-based hydrogen generation/storage system for fuel cell vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Breault, R.W.; Rolfe, J. [Thermo Power Corp., Waltham, MA (United States)

    1998-08-01

    Because of the inherent advantages of high efficiency, environmental acceptability, and high modularity, fuel cells are potentially attractive power supplies. Worldwide concerns over clean environments have revitalized research efforts on developing fuel cell vehicles (FCV). As a result of intensive research efforts, most of the subsystem technology for FCV`s are currently well established. These include: high power density PEM fuel cells, control systems, thermal management technology, and secondary power sources for hybrid operation. For mobile applications, however, supply of hydrogen or fuel for fuel cell operation poses a significant logistic problem. To supply high purity hydrogen for FCV operation, Thermo Power`s Advanced Technology Group is developing an advanced hydrogen storage technology. In this approach, a metal hydride/organic slurry is used as the hydrogen carrier and storage media. At the point of use, high purity hydrogen will be produced by reacting the metal hydride/organic slurry with water. In addition, Thermo Power has conceived the paths for recovery and regeneration of the spent hydride (practically metal hydroxide). The fluid-like nature of the spent hydride/organic slurry will provide a unique opportunity for pumping, transporting, and storing these materials. The final product of the program will be a user-friendly and relatively high energy storage density hydrogen supply system for fuel cell operation. In addition, the spent hydride can relatively easily be collected at the pumping station and regenerated utilizing renewable sources, such as biomass, natural, or coal, at the central processing plants. Therefore, the entire process will be economically favorable and environmentally friendly.

  9. Mechanisms of chemical generation of volatile hydrides for trace element determination (IUPAC Technical Report)

    Czech Academy of Sciences Publication Activity Database

    D'Ulivo, A.; Dědina, Jiří; Mester, Z.; Sturgeon, R. E.; Wang, Q.; Welz, B.

    2011-01-01

    Roč. 83, č. 6 (2011), s. 1283-1340 ISSN 0033-4545 Institutional research plan: CEZ:AV0Z40310501 Keywords : borane complexes * chemical generation of volatile hydrides (CHG) * volatile hydrides Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.789, year: 2011

  10. Quantum-chemical study of hydride transfer in catalytic transformation of paraffins on zeolites

    NARCIS (Netherlands)

    Kazansky, V.B.; Frash, M.V.; Santen, van R.A.; Chon, H.; Ihm, S.-K.; Uh, Y.S.

    1997-01-01

    Ab initio quantum-chemical cluster calculations demonstrate that the activated complexes of hydride transfer reaction in catalytic transformation of paraffins on zeolites very much resembles adsorbed nonclassical carbonium ions. The calculated activation energies for reactions involving propane and

  11. Non-Precious Bimetallic Catalysts for Selective Dehydrogenation of an Organic Chemical Hydride System

    KAUST Repository

    Shaikh Ali, Anaam; Jedidi, Abdesslem; Cavallo, Luigi; Takanabe, Kazuhiro

    2015-01-01

    Methylcyclohexane (MCH)-Toluene (TOL) chemical hydride cycles as a hydrogen carrier system is successful with the selective dehydrogenation reaction of MCH to TOL, which has been achieved only using precious Pt-based catalysts. Herein, we report

  12. Numerical Modeling of Mixing of Chemically Reacting, Non-Newtonian Slurry for Tank Waste Retrieval

    International Nuclear Information System (INIS)

    Yuen, David A.; Onishi, Yasuo; Rustad, James R.; Michener, Thomas E.; Felmy, Andrew R.; Ten, Arkady A.; Hier, Catherine A.

    2000-01-01

    Many highly radioactive wastes will be retrieved by installing mixer pumps that inject high-speed jets to stir up the sludge, saltcake, and supernatant liquid in the tank, blending them into a slurry. This slurry will then be pumped out of the tank into a waste treatment facility. Our objectives are to investigate interactions-chemical reactions, waste rheology, and slurry mixing-occurring during the retrieval operation and to provide a scientific basis for the waste retrieval decision-making process. Specific objectives are to: (1) Evaluate numerical modeling of chemically active, non-Newtonian tank waste mixing, coupled with chemical reactions and realistic rheology; (2) Conduct numerical modeling analysis of local and global mixing of non-Newtonian and Newtonian slurries; and (3) Provide the bases to develop a scientifically justifiable, decision-making support tool for the tank waste retrieval operation

  13. Theoretical study of the chemical properties of cesium hydride; Teoreticke studium chemickych vlastnosti hydridu cezia

    Energy Technology Data Exchange (ETDEWEB)

    Skoviera, J [Univerzita Komenskeho v Bratislave, Prirodovedecka fakulta, Katedra fyzikalnej a teoretickej chemie, 84215 Bratislava (Slovakia)

    2012-04-25

    A theoretical study of radiofrequency source of hydrogen ions in the International Thermonuclear Experimental Reactor (ITER) used a cesium grid as a source of electrons for ionization of hydrogen. In the process of ionization of hydrogen, however, there is a weathering of cesium grid, resulting into a group of undesired products - cesium hydrides and materials derived from cesium hydride. We calculated the potential curves of cesium hydride and of its anion and cation, their spectroscopic properties and partly their electrical properties. To make electrical properties comparable with the experiment, we calculated for all also the vibration corrections. Lack of convergence in RASSCF step caused, that the electrical properties of excited states are still an open question of chemical properties of cesium hydride. (authors)

  14. Modelling the gas transport and chemical processes related to clad oxidation and hydriding

    Energy Technology Data Exchange (ETDEWEB)

    Montgomery, R O; Rashid, Y R [ANATECH Research Corp., San Diego, CA (United States)

    1997-08-01

    Models are developed for the gas transport and chemical processes associated with the ingress of steam into a LWR fuel rod through a small defect. These models are used to determine the cladding regions in a defective fuel rod which are susceptible to massive hydriding and the creation of sunburst hydrides. The brittle nature of zirconium hydrides (ZrH{sub 2}) in these susceptible regions produces weak spots in the cladding which can act as initiation sites for cladding cracks under certain cladding stress conditions caused by fuel cladding mechanical interaction. The modeling of the axial gas transport is based on gaseous bimolar diffusion coupled with convective mass transport using the mass continuity equation. Hydrogen production is considered from steam reaction with cladding inner surface, fission products and internal components. Eventually, the production of hydrogen and its diffusion along the length results in high hydrogen concentration in locations remote from the primary defect. Under these conditions, the hydrogen can attack the cladding inner surface and breakdown the protective ZrO{sub 2} layer locally, initiating massive localized hydriding leading to sunburst hydride. The developed hydrogen evolution model is combined with a general purpose fuel behavior program to integrate the effects of power and burnup into the hydriding kinetics. Only in this manner can the behavior of a defected fuel rod be modeled to determine the conditions the result in fuel rod degradation. (author). 14 refs, 6 figs.

  15. Effects of pig slurry application on soil physical and chemical properties and glyphosate mobility

    Directory of Open Access Journals (Sweden)

    Daniela Aparecida de Oliveira

    2014-10-01

    Full Text Available Pig slurry applied to soil at different rates may affect soil properties and the mobility of chemical compounds within the soil. The purpose of this study was to evaluate the effects of rates of pig slurry application in agricultural areas on soil physical and chemical properties and on the mobility of glyphosate through the soil profile. The study was carried out in the 12th year of an experiment with pig slurry applied at rates of 0 (control, 50, 100 and 200 m³ ha-1 yr-1 on a Latossolo Vermelho distrófico (Hapludox soil. In the control, the quantities of P and K removed by harvested grains were replaced in the next crop cycle. Soil physical properties (bulk density, porosity, texture, and saturated hydraulic conductivity and chemical properties (organic matter, pH, extractable P, and exchangeable K were measured. Soil solution samples were collected at depths of 20, 40 and 80 cm using suction lysimeters, and glyphosate concentrations were measured over a 60-day period after slurry application. Soil physical and chemical properties were little affected by the pig slurry applications, but soil pH was reduced and P levels increased in the surface layers. In turn, K levels were increased in sub-surface layers. Glyphosate concentrations tended to decrease over time but were not affected by pig slurry application. The concentrations of glyphosate found in different depths show that the pratice of this application in agricultural soils has the potential for contamination of groundwater, especially when the water table is the surface and heavy rains occur immediately after application.

  16. Non-Precious Bimetallic Catalysts for Selective Dehydrogenation of an Organic Chemical Hydride System

    KAUST Repository

    Shaikh Ali, Anaam

    2015-07-06

    Methylcyclohexane (MCH)-Toluene (TOL) chemical hydride cycles as a hydrogen carrier system is successful with the selective dehydrogenation reaction of MCH to TOL, which has been achieved only using precious Pt-based catalysts. Herein, we report improved selectivity using non-precious metal nickel-based bimetallic catalysts, where the second metal occupies the unselective step sites.

  17. Production of hydrogen gas from novel chemical hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Aiello, R.; Matthews, M.A. [South Carolina Univ., Chemical Engineering Dept., Columbia, SC (United States); Reger, D.L.; Collins, J.E. [South Carolina Univ., Chemistry and Biochemistry Dept., Columbia, SC (United States)

    1998-12-01

    Six ligand-stabilized complexes have been synthesized and tested for use as hydrogen storage media for portable fuel cell applications. The new hydrides are: [HC(3,5-Me{sub 2}pz){sub 3}]LiBH{sub 4} (1), [[H{sub 2}C(3,5-Me{sub 2}pz){sub 2}]LiBH{sub 4})]{sub 2} (2) (pz = pyrazolyl), [(TMEDA)Li(BH{sub 4})]{sub 2} (3) (TMEDA (CH{sub 3}){sub 2}NCH{sub 2}CH{sub 2}N(CH{sub 3}){sub 2}), [HC(pz){sub 3}]LiBH{sub 4} (4), [[H{sub 2}C(pz){sub 2}]Li(BH{sub 4})]{sub 2} (5) and Mg(BH{sub 4}){sub 2}3THF (6) (THF = tetrahydrofuran). Hydrolysis reactions of the compounds liberate hydrogen in quantities which range from 56 to 104 ({+-}5%) of the theoretical yield. Gas chromatographic analysis of the product gases from these reactions indicate that hydrogen is the only gas produced. Thermally initiated reactions of the novel compounds with NH{sub 4}Cl were unsuccessful. Although the amount of hydrogen energy which can be theoretically obtained per unit weight is lower than that of the classical hydrides such as LiBH{sub 4} and NaBH{sub 4}, the reactions are less violent and hydrolysis of compounds 1, 2, 4, 5 and 6 releases less heat per mole of hydrogen generated. (Author)

  18. High-Frequency H-1 NMR Chemical Shifts of Sn-II and Pb-II Hydrides Induced by Relativistic Effects: Quest for Pb-II Hydrides

    Czech Academy of Sciences Publication Activity Database

    Vícha, J.; Marek, R.; Straka, Michal

    2016-01-01

    Roč. 55, č. 20 (2016), s. 10302-10309 ISSN 0020-1669 Institutional support: RVO:61388963 Keywords : hydrides of TlI and PbII * high-frequency 1H chemical shifts * relativistic effects Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.857, year: 2016

  19. The role of chemical free energy and elastic strain in the nucleation of zirconium hydride

    International Nuclear Information System (INIS)

    Barrow, A.T.W.; Toffolon-Masclet, C.; Almer, J.; Daymond, M.R.

    2013-01-01

    In this work a combination of synchrotron X-ray diffraction and thermodynamic modelling has been used to study the dissolution and precipitation of zirconium hydride in α-Zr establishing the role of elastic misfit strain and chemical free energy in the α → α + δ phase transformation. The nucleation of zirconium hydride is dominated by the chemical free energy where the chemical driving force for hydride precipitation is proportional to the terminal-solid solubility for precipitation and can be predicted by a function that is analogous to the universal nucleation parameter for the bainite transformation in ferrous alloys. The terminal-solid solubility for precipitation was found to be kinetically limited ⩾287 °C at a cooling rate of 5 °C min −1 or greater. The terminal solubilities were established using an offset method applied to the lattice strain data where a resolution of ∼10 wppm H can be achieved in the 〈c〉-direction. This is aided by the introduction of intra-granular strains in the 〈c〉-direction during cooling as a result of the thermal expansion anisotropy which increases the anisotropy associated with the misfitting H atoms within the α-Zr lattice

  20. Fermentation of Anaerobic Cow Waste as Bio-Slurry Organic Fertilizer and Nitrogen Chemical Fertilizer on Soybean

    Science.gov (United States)

    Yafizham; Sutarno

    2018-02-01

    The study aimed was to evaluate the effect of bio-slurry organic fertilizer and urea chemical fertilizer combination on fresh material weight, phosphorus and potassium soybean straw, and seed weight per soybean plant plot. The experiment was conducted with a randomized block design with a single treatment repeated 5 times consisting of P0: control (without fertilizer), P1: bio-slurry 10 t/ha + 25 kg of N/ha, P2: bio-slurry 10 t/ha + 50 kg of N/ha, P3: bio-slurry 10 t/ha + 75 kg of N/ha, P4: bio-slurry 10 t/ha + 100 kg of N/ha and P5: bio-slurry 10 t/ha. The results showed that bio-slurry treatment of 10 t/ha + 25 kg of N/ha resulted in the highest fresh weight and dry weight of soybean plants, respectively of 240.7 g and 22.33 g, but not significantly different from the bio-slurry treatment of 10 t/ha + 50 kg of N/ha which yielded fresh weight of 197.7 g and a dry weight of 19.08 g. P production of 10.23 g per plant was significantly higher than other treatments but didn’t differ significantly between P2 and P4 treatments of 8.05 and 7.17 g per plant. The bio-slurry treatment of 10 t/ha + 25 kg of N/ha also yielded K of 6.46 g per plant butn’t unlike the bio-slurry treatment of 10 t/ha + 50 kg of N/ha. While the number of pods per plant and weight of 100 grains of the highest soybean seeds were also produced from bio-slurry treatment of 10 t/ha + 25 kg of N/ha.

  1. Chemical attributes of a Hapludox soil after nine years of pig slurry application

    Directory of Open Access Journals (Sweden)

    Milton da Veiga

    2012-12-01

    Full Text Available The objective of this study was to evaluate the pig slurry application effects on chemical attributes of a Hapludox soil managed under no-tillage system. Treatments consisted of 50, 100 and 200 m³ ha-1 per year of pig slurry application, and a control with replacement of P and K exported through harvested grains. Attributes related to soil chemical reaction, exchange complex, and nutrient contents were determined in soil samples collected in the ninth year of experimentation from 0 - 0.025, 0.025 - 0.05, 0.05 - 0.10, 0.10 - 0.20, 0.20 - 0.40 and 0.40 - 0.60 m soil depths. The continuous application of high doses of pig slurry on the Oxisol surface under no-tillage acidifies the soil and increases Al, P, Cu, and Zn contents down to 0.2-m depth, and K levels down to 0.6-m depth.

  2. YNi and its hydrides: Phase stabilities, electronic structures and chemical bonding properties from first principles

    International Nuclear Information System (INIS)

    Matar, S.F.; Nakhl, M.; Al Alam, A.F.; Ouaini, N.; Chevalier, B.

    2010-01-01

    Graphical abstract: Base centered orthorhombic YNiH X structure. For x = 3, only H1 and H2 are present. Highest hydrogen content YNiH 4 is obtained when H3 are added. - Abstract: Within density functional theory, establishing the equations of states of YNi in two different controversial structures in the literature, leads to determine the orthorhombic FeB-type as the ground state one with small energy difference. For YNiH 3 and YNiH 4 hydrides crystallizing in the orthorhombic CrB-type structure the geometry optimization and the ab initio determination of the H atomic positions show that the stability of hydrogen decreases from the tri- to the tetra- hydride. New states brought by hydrogen within the valence band lead to its broadening and to enhanced localization of metal density of states. The chemical bonding analysis shows a preferential Ni-H bonding versus Y-H.

  3. YNi and its hydrides: Phase stabilities, electronic structures and chemical bonding properties from first principles

    Energy Technology Data Exchange (ETDEWEB)

    Matar, S.F., E-mail: matar@icmcb-bordeaux.cnrs.fr [CNRS, Universite de Bordeaux, ICMCB, 87 avenue du Docteur Albert Schweitzer, F-33608 Pessac (France); Nakhl, M. [Universite Libanaise, Laboratoire de Chimie-Physique des Materiaux LCPM, Fanar (Lebanon); Al Alam, A.F.; Ouaini, N. [Universite Saint-Esprit de Kaslik, Faculte des Sciences et de Genie Informatique, Jounieh (Lebanon); Chevalier, B. [CNRS, Universite de Bordeaux, ICMCB, 87 avenue du Docteur Albert Schweitzer, F-33608 Pessac (France)

    2010-11-25

    Graphical abstract: Base centered orthorhombic YNiH{sub X} structure. For x = 3, only H1 and H2 are present. Highest hydrogen content YNiH{sub 4} is obtained when H3 are added. - Abstract: Within density functional theory, establishing the equations of states of YNi in two different controversial structures in the literature, leads to determine the orthorhombic FeB-type as the ground state one with small energy difference. For YNiH{sub 3} and YNiH{sub 4} hydrides crystallizing in the orthorhombic CrB-type structure the geometry optimization and the ab initio determination of the H atomic positions show that the stability of hydrogen decreases from the tri- to the tetra- hydride. New states brought by hydrogen within the valence band lead to its broadening and to enhanced localization of metal density of states. The chemical bonding analysis shows a preferential Ni-H bonding versus Y-H.

  4. Metal hydride/chemical heat-pump development project. Phase I. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Argabright, T.A.

    1982-02-01

    The metal hydride/chemical heat pump (MHHP) is a chemical heat pump containing two hydrides for the storage and/or recovery of thermal energy. It utilizes the heat of reaction of hydrogen with specific metal alloys. The MHHP design can be tailored to provide heating and/or cooling or temperature upgrading over a wide range of input and ambient temperatures. The system can thus be used with a variety of heat sources including waste heat, solar energy or a fossil fuel. The conceptual design of the MHHP was developed. A national market survey including a study of applications and market sectors was conducted. The technical tasks including conceptual development, thermal and mechanical design, laboratory verification of design and material performance, cost analysis and the detailed design of the Engineering Development Test Unit (EDTU) were performed. As a result of the market study, the temperature upgrade cycle of the MHHP was chosen for development. Operating temperature ranges for the upgrader were selected to be from 70 to 110/sup 0/C (160 to 230/sup 0/F) for the source heat and 140 to 190/sup 0/C (280 to 375/sup 0/F) for the product heat. These ranges are applicable to many processes in industries such as food, textile, paper and pulp, and chemical. The hydride pair well suited for these temperatures is LaNi/sub 5//LaNi/sub 4/ /sub 5/Al/sub 0/ /sub 5/. The EDTU was designed for the upgrade cycle. It is a compact finned tube arrangement enclosed in a pressure vessel. This design incorporates high heat transfer and low thermal mass in a system which maximizes the coefficient of performance (COP). It will be constructed in Phase II. Continuation of this effort is recommended.

  5. DFT modeling of the electronic and magnetic structures and chemical bonding properties of intermetallic hydrides

    International Nuclear Information System (INIS)

    Al Alam, A.F.

    2009-06-01

    This thesis presents an ab initio study of several classes of intermetallics and their hydrides. These compounds are interesting from both a fundamental and an applied points of view. To achieve this aim two complementary methods, constructed within the DFT, were chosen: (i) pseudo potential based VASP for geometry optimization, structural investigations and electron localization mapping (ELF), and (ii) all-electrons ASW method for a detailed description of the electronic structure, chemical bonding properties following different schemes as well as quantities depending on core electrons such as the hyperfine field. A special interest is given with respect to the interplay between magneto-volume and chemical interactions (metal-H) effects within the following hydrided systems: binary Laves (e.g. ScFe 2 ) and Haucke (e.g. LaNi 5 ) phases on one hand, and ternary cerium based (e.g. CeRhSn) and uranium based (e.g. U 2 Ni 2 Sn) alloys on the other hand. (author)

  6. The Effect of Chemical Amendments Used for Phosphorus Abatement on Greenhouse Gas and Ammonia Emissions from Dairy Cattle Slurry: Synergies and Pollution Swapping.

    Directory of Open Access Journals (Sweden)

    Raymond B Brennan

    Full Text Available Land application of cattle slurry can result in incidental and chronic phosphorus (P loss to waterbodies, leading to eutrophication. Chemical amendment of slurry has been proposed as a management practice, allowing slurry nutrients to remain available to plants whilst mitigating P losses in runoff. The effectiveness of amendments is well understood but their impacts on other loss pathways (so-called 'pollution swapping' potential and therefore the feasibility of using such amendments has not been examined to date. The aim of this laboratory scale study was to determine how the chemical amendment of slurry affects losses of NH3, CH4, N2O, and CO2. Alum, FeCl2, Polyaluminium chloride (PAC- and biochar reduced NH3 emissions by 92, 54, 65 and 77% compared to the slurry control, while lime increased emissions by 114%. Cumulative N2O emissions of cattle slurry increased when amended with alum and FeCl2 by 202% and 154% compared to the slurry only treatment. Lime, PAC and biochar resulted in a reduction of 44, 29 and 63% in cumulative N2O loss compared to the slurry only treatment. Addition of amendments to slurry did not significantly affect soil CO2 release during the study while CH4 emissions followed a similar trend for all of the amended slurries applied, with an initial increase in losses followed by a rapid decrease for the duration of the study. All of the amendments examined reduced the initial peak in CH4 emissions compared to the slurry only treatment. There was no significant effect of slurry amendments on global warming potential (GWP caused by slurry land application, with the exception of biochar. After considering pollution swapping in conjunction with amendment effectiveness, the amendments recommended for further field study are PAC, alum and lime. This study has also shown that biochar has potential to reduce GHG losses arising from slurry application.

  7. The Effect of Chemical Amendments Used for Phosphorus Abatement on Greenhouse Gas and Ammonia Emissions from Dairy Cattle Slurry: Synergies and Pollution Swapping.

    Science.gov (United States)

    Brennan, Raymond B; Healy, Mark G; Fenton, Owen; Lanigan, Gary J

    2015-01-01

    Land application of cattle slurry can result in incidental and chronic phosphorus (P) loss to waterbodies, leading to eutrophication. Chemical amendment of slurry has been proposed as a management practice, allowing slurry nutrients to remain available to plants whilst mitigating P losses in runoff. The effectiveness of amendments is well understood but their impacts on other loss pathways (so-called 'pollution swapping' potential) and therefore the feasibility of using such amendments has not been examined to date. The aim of this laboratory scale study was to determine how the chemical amendment of slurry affects losses of NH3, CH4, N2O, and CO2. Alum, FeCl2, Polyaluminium chloride (PAC)- and biochar reduced NH3 emissions by 92, 54, 65 and 77% compared to the slurry control, while lime increased emissions by 114%. Cumulative N2O emissions of cattle slurry increased when amended with alum and FeCl2 by 202% and 154% compared to the slurry only treatment. Lime, PAC and biochar resulted in a reduction of 44, 29 and 63% in cumulative N2O loss compared to the slurry only treatment. Addition of amendments to slurry did not significantly affect soil CO2 release during the study while CH4 emissions followed a similar trend for all of the amended slurries applied, with an initial increase in losses followed by a rapid decrease for the duration of the study. All of the amendments examined reduced the initial peak in CH4 emissions compared to the slurry only treatment. There was no significant effect of slurry amendments on global warming potential (GWP) caused by slurry land application, with the exception of biochar. After considering pollution swapping in conjunction with amendment effectiveness, the amendments recommended for further field study are PAC, alum and lime. This study has also shown that biochar has potential to reduce GHG losses arising from slurry application.

  8. Phytotoxicity and Chemical Characterization of Compost Derived from Pig Slurry Solid Fraction for Organic Pellet Production

    Directory of Open Access Journals (Sweden)

    Niccolò Pampuro

    2017-11-01

    Full Text Available The phytotoxicity of four different composts obtained from pig slurry solid fraction composted by itself (SSFC and mixed with sawdust (SC, woodchips (WCC and wheat straw (WSC was tested with bioassay methods. For each compost type, the effect of water extracts of compost on seed germination and primary root growth of cress (Lepidium Sativum L. was investigated. Composts were also chemically analysed for total nitrogen, ammonium, electrical conductivity and heavy metal (Cu and Zn. The chemicals were correlated to phytotoxicity indices. The mean values of the germination index (GI obtained were 160.7, 187.9, 200.9 and 264.4 for WSC, WCC, SC and SSFC, respectively. Growth index (GrI ranged from the 229.4%, the highest value, for SSFC, followed by 201.9% for SC, and 193.1% for WCC, to the lowest value, 121.4%, for WSC. Electrical conductivity showed a significant and negative correlation with relative seed germination at the 50% and 75% concentrations. A strong positive correlation was found for water-extractable Cu with relative root growth and germination index at the 10% concentration. Water-extractable Zn showed a significant positive correlation with relative root growth and GI at the 10% concentration. These results highlighted that the four composts could be used for organic pellet production and subsequently distributed as a soil amendment with positive effects on seed germination and plant growth (GI > 80%.

  9. Numerical Modeling of Mixing of Chemically Reacting, Non-Newtonian Slurry for Tank Waste Retrieval

    International Nuclear Information System (INIS)

    Yuen, D.A.; Onishi, Y.

    2001-01-01

    In the U.S. Department of Energy (DOE) complex, 100 million gallons of radioactive and chemical wastes from plutonium production are stored in 281 underground storage tanks. Retrieval of the wastes from the tanks is the first step in its ultimate treatment and disposal. Because billions of dollars are being spent on this effort, waste retrieval demands a strong scientific basis for its successful completion. As will be discussed in Section 4.2, complex interactions among waste chemical reactions, rheology, and mixing of solid and liquid tank waste (and possibly with a solvent) will occur in DSTs during the waste retrieval (mixer pump) operations. The ultimate goal of this study was to develop the ability to simulate the complex chemical and rheological changes that occur in the waste during processing for retrieval. This capability would serve as a scientific assessment tool allowing a priori evaluation of the consequences of proposed waste retrieval operations. Hanford tan k waste is a multiphase, multicomponent, high-ionic strength, and highly basic mixture of liquids and solids. Wastes stored in the 4,000-m3 DSTs will be mixed by 300-hp mixer pumps that inject high-speed (18.3 m/s) jets to stir up the sludge and supernatant liquid for retrieval. During waste retrieval operations, complex interactions occur among waste mixing, chemical reactions, and associated rheology. Thus, to determine safe and cost-effective operational parameters for waste retrieval, decisions must rely on new scientific knowledge to account for physical mixing of multiphase flows, chemical reactions, and waste rheology. To satisfy this need, we integrated a computational fluid dynamics code with state-of-the-art equilibrium and kinetic chemical models and non-Newtonian rheology (Onishi (and others) 1999). This development is unique and holds great promise for addressing the complex phenomena of tank waste retrieval. The current model is, however, applicable only to idealized tank waste

  10. Conference 'Chemistry of hydrides' Proceedings

    International Nuclear Information System (INIS)

    1991-07-01

    This collection of thesis of conference of Chemistry hydrides presents the results of investigations concerning of base questions of chemistry of nonorganic hydrides, including synthesis questions, studying of physical and chemical properties, thermodynamics, analytical chemistry, investigation of structure, equilibriums in the systems of metal-hydrogen, behaviour of nonorganic hydrides in non-water mediums and applying investigations in the chemistry area and technology of nonorganic hydrides

  11. Effects of Pig Slurry Application and Crops on Phosphorus Content in Soil and the Chemical Species in Solution

    Directory of Open Access Journals (Sweden)

    Lessandro De Conti

    2015-06-01

    Full Text Available The application of pig slurry rates and plant cultivation can modify the soil phosphorus (P content and distribution of chemical species in solution. The purpose of this study was to evaluate the total P, available P and P in solution, and the distribution of chemical P species in solution, in a soil under longstanding pig slurry applications and crop cultivation. The study was carried out in soil columns with undisturbed structure, collected in an experiment conducted for eight years in the experimental unit of the Universidade Federal de Santa Maria (UFSM, Santa Maria (RS. The soil was an Argissolo Vermelho distrófico arênico (Typic Hapludalf, subjected to applications of 0, 20, 40, and 80 m3 ha-1 pig slurry. Soil samples were collected from the layers 0-5, 5-10, 10-20, 20-30, 30-40, and 40-60 cm, before and after black oat and maize grown in a greenhouse, for the determination of available P, total P and P in the soil solution. In the solution, the concentration of the major cations, anions, dissolved organic carbon (DOC, and pH were determined. The distribution of chemical P species was determined by software Visual Minteq. The 21 pig slurry applications increased the total P content in the soil to a depth of 40 cm, and the P extracted by Mehlich-1 and from the solution to a depth of 30 cm. Successive applications of pig slurry changed the balance between the solid and liquid phases in the surface soil layers, increasing the proportion of the total amount of P present in the soil solution, aside from changing the chemical species in the solution, reducing the percentage complexed with Al and increasing the one complexed with Ca and Mg in the layers 0-5 and 5-10 cm. Black oat and maize cultivation increased pH in the solution, thereby increasing the proportion of HPO42- and reducing H2PO4- species.

  12. Paraffin Alkylation Using Zeolite Catalysts in a slurry reactor: Chemical Engineering Principles to Extend Catalyst Lifetime

    NARCIS (Netherlands)

    Jong, K.P. de; Mesters, C.M.A.M.; Peferoen, D.G.R.; Brugge, P.T.M. van; Groot, C. de

    1996-01-01

    The alkylation of isobutane with 2-butene is carried out using a zeolitic catalyst in a well stirred slurry reactor. Whereas application of fixed bed technology using a solid acid alkylation catalyst has in the led to catalysts lifetimes in the range of minutes, in this work we report catalyst

  13. Pressurized Vessel Slurry Pumping

    International Nuclear Information System (INIS)

    Pound, C.R.

    2001-01-01

    This report summarizes testing of an alternate ''pressurized vessel slurry pumping'' apparatus. The principle is similar to rural domestic water systems and ''acid eggs'' used in chemical laboratories in that material is extruded by displacement with compressed air

  14. Influence of different fibre sources in diets for growing pigs on chemical composition of faeces and slurry and ammonia emission from slurry

    DEFF Research Database (Denmark)

    Hansen, Michael Jørgen; Chwalibog, André; Tauson, Anne-Helene

    2007-01-01

    The present study was carried out to investigate how three different fibre sources, sugar beet pulp, soya bean hulls and pectin residue, in diets for growing pigs influenced the concentration of short-chain fatty acids (SCFA) in faeces, pH-value in faeces and slurry, excretion of nitrogen in urine...

  15. Integrated use of plant growth promoting rhizobacteria, biogas slurry and chemical nitrogen for sustainable production of maize under salt-affected conditions

    International Nuclear Information System (INIS)

    Ahmad, M.; Jamil, M.; Akhtar, F.U.Z.

    2014-01-01

    Salinity is one of the most critical constraints hampering agricultural production throughout the world, including Pakistan. Some plant growth promoting rhizobacteria (PGPR) have the ability to reduce the deleterious effect of salinity on plants due to the presence of ACC-deaminase enzyme along with some other mechanisms. The integrated use of organic, chemical and biofertilizers can reduce dependence on expensive chemical inputs. To sustain high crop yields without deterioration of soil fertility, it is important to work out optimal combination of chemical and biofertilizers, and manures in the cropping system. A pot trial was conducted to study the effect of integrated use of PGPR, chemical nitrogen, and biogas slurry for sustainable production of maize under salt-stressed conditions and for good soil health. Results showed that sole application of PGPR, chemical nitrogen and biogas slurry enhanced maize growth but their combined application was more effective. Maximum improvement in maize growth, yield, ionic concentration in leaves and nutrient concentration in grains was observed in the treatment where PGPR and biogas slurry was used in the presence of 100% recommended nitrogen as chemical fertilizer. It also improved the soil pH, ECe, and available N, P and K contents. It is concluded that integrated use of PGPR, biogas slurry and chemical nitrogen not only enhanced maize growth, yield and quality but also improved soil health. So, it may be evaluated under field conditions to get sustained yield of maize from salt-affected soils. (author)

  16. Leaf tissues proportion and chemical composition of Axonopus jesuiticus x A. scoparius as a function of pig slurry application

    Directory of Open Access Journals (Sweden)

    Cristiano Reschke Lajús

    2014-02-01

    Full Text Available This study aimed to evaluate the chemical and anatomical attributes of leaves of giant missionary grass to application of 0, 62, 124, 186, 248 and 310m³ ha-1 of pig slurry. At 83 days after the last application of fertilizer, the leaf blades were collected, fixed in FAA 70%, sectioned, stained, photographed and digitalized. The transversal section of leaf blades were evaluated for proportion of epidermis, lignified vascular tissue + sclerenchyma, non-lignified vascular tissue and parenchyma with an image-processing system calibrated to 1mm pixel-1. Leaf samples were analyzed for crude protein, acid detergent fiber, neutral detergent fiber and hemicellulose content by near infrared reflectance spectroscopy. The pig slurry application up to 310m³ ha-1 significantly increased the percentage of crude protein, parenchyma, epidermis, non-lignified vascular tissue and hemicellulose, while decreasing the percentage of acid detergent fiber and lignified vascular tissue + sclerenchyma. The Pearson's correlation was positive between crude protein and non-lignified vascular tissue, and between acid detergent fiber and lignified vascular tissue + sclerenchyma. The percentage of hemicellulose was positively correlated with epidermis, parenchyma and non-lignified vascular tissue. A negative correlation between acid detergent fiber and epidermis, parenchyma and non-lignified vascular tissue was observed.

  17. Preparation and chemical crystallographic study of new hydrides and hydro-fluorides of ionic character; Preparation et etude cristallochimique de nouveaux hydrures et fluorohydrures a caractere ionique

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hyung-Ho

    1988-07-22

    Within the context of a growing interest in the study of reversible hydrides with the perspective of their application in hydrogen storage, this research thesis more particularly addressed the case of ternary hydrides and fluorides, and of hydro-fluorides. The author reports the development of a method of preparation of alkaline hydrides, of alkaline earth hydrides and of europium hydride, and then the elaboration of ternary hydrides. He addresses the preparation of caesium fluorides and of calcium or nickel fluorides, of Europium fluorides, and of ternary fluorides. Then, he addresses the preparation of hydro-fluorides (caesium, calcium, europium fluorides, and caesium and nickel fluorides). The author presents the various experimental techniques: chemical analysis, radio-crystallographic analysis, volumetric mass density measurement, magnetic measurements, ionic conductivity measurements, Moessbauer spectroscopy, and nuclear magnetic resonance. He reports the crystallographic study of some ternary alkaline and alkaline-earth hydrides (KH-MgH{sub 2}, RbH-CaH{sub 2}, CsH-CaH{sub 2}, RbH-MgH{sub 2} and CsH-MgH{sub 2}) and of some hydro-fluorides (CsCaF{sub 2}H, EuF{sub 2}H, CsNiF{sub 2}H) [French] Dans une premiere partie, de nouveaux hydrures ternaires ont ete prepares et caracterises. Les systemes etudies sont AH-MH 2 (A = K, Rb, Cs et M = Mg, Ca). Dans les systemes AH-MgH 2 l'evolution structurale a ete discutee en fonction du caractere iono-covalent de la liaison magnesium-hydrogene. Dans une deuxieme partie, plusieurs nouveaux fluorohydrures ont ete mis en evidence. L'effet de la substitution de l'hydrogene au fluor dans ces phases a ete etudiee en utilisant la RMN, la spectroscopie Moessbauer, la conductivite ionique et les mesures magnetiques.

  18. Complex Hydrides for Hydrogen Storage

    Energy Technology Data Exchange (ETDEWEB)

    Slattery, Darlene; Hampton, Michael

    2003-03-10

    This report describes research into the use of complex hydrides for hydrogen storage. The synthesis of a number of alanates, (AIH4) compounds, was investigated. Both wet chemical and mechano-chemical methods were studied.

  19. Efficient Hydrogenolysis of Alkanes at Low Temperature and Pressure Using Tantalum Hydride on MCM-41, and a Quantum Chemical Study

    KAUST Repository

    Polshettiwar, Vivek

    2012-02-10

    Hydrogenolysis of hydrocarbons is of considerable technological importance for applications such as the hydroprocessing of petrochemical feedstocks to generate high-value and useful chemicals and fuels. We studied the catalytic activity of tantalum hydride supported on MCM-41 for the hydrogenolysis of alkanes at low temperature and low atmospheric pressure in a dynamic reactor. The reactions proceed with good turnover numbers, and the catalyst could be reused for several times, which makes the overall catalytic process sustainable. We derived the plausible mechanism by using DFT calculations and identified the preferred pathways by the analysis of potential energy surface. Our results and the proposed reaction mechanism demonstrate the viability of the "catalyst-by-design" approach. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Efficient Hydrogenolysis of Alkanes at Low Temperature and Pressure Using Tantalum Hydride on MCM-41, and a Quantum Chemical Study

    KAUST Repository

    Polshettiwar, Vivek; Pasha, Farhan Ahmad; De Mallmann, Aimery; Norsic, Sé bastien; Thivolle-Cazat, Jean; Basset, Jean-Marie

    2012-01-01

    Hydrogenolysis of hydrocarbons is of considerable technological importance for applications such as the hydroprocessing of petrochemical feedstocks to generate high-value and useful chemicals and fuels. We studied the catalytic activity of tantalum hydride supported on MCM-41 for the hydrogenolysis of alkanes at low temperature and low atmospheric pressure in a dynamic reactor. The reactions proceed with good turnover numbers, and the catalyst could be reused for several times, which makes the overall catalytic process sustainable. We derived the plausible mechanism by using DFT calculations and identified the preferred pathways by the analysis of potential energy surface. Our results and the proposed reaction mechanism demonstrate the viability of the "catalyst-by-design" approach. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Determination of phosphorus in metals by neutron activation and chemical separation as hydride

    International Nuclear Information System (INIS)

    Rouchaud, J.C.; Fedoroff, M.

    1993-01-01

    Phosphorous at trace levels alters the properties of metals and alloys. Its determination was investigated by radiochemical neutron activation analysis. Separation by solvent extraction or by evolution as P 0 showed to be neither selective nor quantitative in presence of a metallic matrix. Therefore, a new method of separation by reduction to phosphorous hydride followed by liquid scintillation counting was investigated. This method is quantitative in the case of non-radioactive iron doped with radioactive phosphorus. At present, the separation is not quantitative for irradiation iron samples, owing probably to hot atom or radiation effects. A detection limit of 0.002 μg is expected. (author) 10 refs.; 1 fig.; 3 tabs

  2. Chemical and toxicological characterization of slurry reactor biotreatment of explosives-contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Griest, W.H.; Stewart, A.J.; Vass, A.A.; Ho, C.H.

    1998-08-01

    Treatment of 2,4,6-trinitrotoluene (TNT)-contaminated soil in the Joliet Army Ammunition Plant (JAAP) soil slurry bioreactor (SSBR) eliminated detectable TNT but left trace levels of residual monoamino and diamino metabolites under some reactor operating conditions. The reduction of solvent-extractable bacterial mutagenicity in the TNT-contaminated soil was substantial and was similar to that achieved by static pile composts at the Umatilla Army Depot Activity (UMDA) field demonstration. Aquatic toxicity to Ceriodaphnia dubia from TNT in the leachates of TNT-contaminated soil was eliminated in the leachates of JAAP SSBR product soil. The toxicity of soil product leachates to Ceriodaphnia dubia was reasonably predicted using the specific toxicities of the components detected, weighted by their leachate concentrations. In samples where TNT metabolites were observed in the soil product and its leachates, this method determined that the contribution to predicted toxicity values was dominated by trace amounts of the diamino-metabolites, which are very toxic to ceriodaphnia dubia. When the SSBR operating conditions reduced the concentrations of TNT metabolites in the product soils and their leachates to undetectable concentrations, the main contributors to predicted aquatic toxicity values appeared to be molasses residues, potassium, and bicarbonate. Potassium and bicarbonate are beneficial or benign to the environment, and molasses residues are substantially degraded in the environment. Exotoxins, pathogenic bacteria, inorganic particles, ammonia, and dissolved metals did not appear to be important to soil product toxicity.

  3. Fiber-reinforced ceramic matrix composites processed by a hybrid technique based on chemical vapor infiltration, slurry impregnation and spark plasma sintering

    International Nuclear Information System (INIS)

    Magnant, J.; Pailler, R.; Le Petitcorps, Y.; Maille, L.; Guette, A.; Marthe, J.

    2013-01-01

    Fabrication of multidirectional continuous carbon and silicon carbide fiber reinforced ceramic matrix composites (CMC) by a new short time hybrid process was studied. This process is based, first, on the deposition of fiber interphase and coating by chemical vapor infiltration, next, on the introduction of silicon nitride powders into the fibrous preform by slurry impregnation and, finally, on the densification of the composite by liquid phase spark plasma sintering (LP-SPS). The homogeneous introduction of the ceramic charges into the multidirectional fiber pre-forms was realized by slurry impregnation from highly concentrated and well-dispersed aqueous colloid suspensions. The chemical degradation of the carbon fibers during the fabrication was prevented by adapting the sintering pressure cycle. The composites manufactured are dense. Microstructural analyses were conducted to explain the mechanical properties achieved. One main important result of this study is that LP-SPS can be used in some hybrid processes to densify fiber reinforced CMC. (authors)

  4. Organic chemical hydrides as storage medium of hydrogen on the basis of superheated liquid-film concept

    International Nuclear Information System (INIS)

    Shinya Hodoshima; Atsushi Shono; Kazumi Satoh; Yasukazu Saito

    2006-01-01

    A catalysis pair of tetralin dehydrogenation / naphthalene hydrogenation has been proposed in the present paper as an organic chemical hydride for operating stationary fuel cells. Catalytic naphthalene hydrogenation, having been commercialized since the 1940's, proceeds to generate decalin via tetralin as an intermediate. The storage capacities of tetralin (3.0 wt%, 28.2 kg-H 2 / m 3 ) are lower than decalin (7.3 wt%, 64.8 kg-H 2 / m 3 ) but both tetralin dehydrogenation and naphthalene hydrogenation are much faster than the decalin / naphthalene pair. Moreover, existing infrastructures, e.g., gas station and tank lorry, are available for storage, transportation and supply of hydrogen. As for the stationary fuel cells with large space for hydrogen storage, tetralin as a hydrogen carrier is superior to decalin in terms of fast hydrogen supply. Rapid hydrogen supply from tetralin under mild conditions was only accomplished with the carbon supported metal catalysts in the 'superheated liquid-film states' under reactive distillation conditions. In contrast to the ordinary suspended states, the catalyst layer superheated in the liquid-film state gave high catalytic performances at around 250 C. As a result, serious coke formation over the catalyst surface and excessive exergy consumption were prevented simultaneously. (authors)

  5. Hydrogen storage by organic chemical hydrides and hydrogen supply to fuel cells with superheated liquid-film-type catalysis

    International Nuclear Information System (INIS)

    Hodoshima, S.; Shono, A.; Sato, K.; Saito, Y.

    2004-01-01

    Organic chemical hydrides, consisting of decalin / naphthalene and tetralin / naphthalene pairs, have been proposed as the storage medium of hydrogen for operating fuel cells in mobile and static modes. The target values in the DOE Hydrogen Plan, U.S., on storage ( 6.5 wt%, 62.0 kg-H 2 / m 3 ) are met with decalin ( 7.3 wt%, 64.8 kg-H 2 / m 3 ). In addition, existing gas stations and tank lorries are available for storage and supply of hydrogen by utilizing the decalin / naphthalene pair, suggesting that decalin is suitable for operating fuel-cell vehicles. Tetralin dehydrogenation proceeds quite rapidly, assuring a predominant power density, though its storage densities ( 3.0 wt%, 28.2 kg-H 2 / m 3 ) are relatively low. Efficient hydrogen supply from decalin or tetralin by heating at 210-280 o C was attained only with the carbon-supported nano-size metal catalysts in the 'superheated liquid-film states' under reactive distillation conditions, where coke formation over the catalyst surface was prevented. The catalyst layer superheated in the liquid-film states gave high reaction rates and conversions, minimizing the evaporation loss under boiling conditions and exergy loss in hydrogen energy systems. (author)

  6. Compact PEM fuel cell system combined with all-in-one hydrogen generator using chemical hydride as a hydrogen source

    International Nuclear Information System (INIS)

    Kim, Jincheol; Kim, Taegyu

    2015-01-01

    Highlights: • Compact fuel cell system was developed for a portable power generator. • Novel concept using an all-in-one reactor for hydrogen generation was proposed. • Catalytic reactor, hydrogen chamber and separator were combined in a volume. • The system can be used to drive fuel cell-powered unmanned autonomous systems. - Abstract: Compact fuel cell system was developed for a portable power generator. The power generator features a polymer electrolyte membrane fuel cell (PEMFC) using a chemical hydride as a hydrogen source. The hydrogen generator extracted hydrogen using a catalytic hydrolysis from a sodium borohydride alkaline solution. A novel concept using an all-in-one reactor was proposed in which a catalyst, hydrogen chamber and byproduct separator were combined in a volume. In addition, the reactor as well as a pump, cooling fans, valves and controller was integrated in a single module. A 100 W PEMFC stack was connected with the hydrogen generator and was evaluated at various load conditions. It was verified that the stable hydrogen supply was achieved and the developed system can be used to drive fuel cell-powered unmanned autonomous systems.

  7. Results for the Third Quarter 2014 Tank 50 WAC slurry sample: Chemical and radionuclide contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, Charles L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-01-08

    This report details the chemical and radionuclide contaminant results for the characterization of the 2014 Third Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time.1 Information from this characterization will be used by DWPF & Saltstone Facility Engineering (DSFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System.

  8. Results For The Fourth Quarter 2014 Tank 50 WAC Slurry Sample: Chemical And Radionuclide Contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-09-30

    This report details the chemical and radionuclide contaminant results for the characterization of the Calendar Year (CY) 2014 Fourth Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time. Information from this characterization will be used by DWPF & Saltstone Facility Engineering (DSFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System.

  9. Results for the second quarter 2014 tank 50 WAC slurry sample chemical and radionuclide contaminants

    International Nuclear Information System (INIS)

    Bannochie, C.

    2014-01-01

    This report details the chemical and radionuclide contaminant results for the characterization of the 2014 Second Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time. Information from this characterization will be used by DWPF & Saltstone Facility Engineering (DSFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System

  10. Results For The Second Quarter 2013 Tank 50 WAC Slurry Sample: Chemical And Radionuclide Contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, Christopher J.

    2013-07-31

    This report details the chemical and radionuclide contaminant results for the characterization of the 2013 Second Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time. Information from this characterization will be used by Saltstone Facility Engineering (SFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System.

  11. Slurry reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kuerten, H; Zehner, P [BASF A.G., Ludwigshafen am Rhein (Germany, F.R.)

    1979-08-01

    Slurry reactors are designed on the basis of empirical data and model investigations. It is as yet not possible to calculate the flow behavior of such reactors. The swarm of gas bubbles and cluster formations of solid particles and their interaction in industrial reactors are not known. These effects control to a large extent the gas hold-up, the gas-liquid interface and, similarly as in bubble columns, the back-mixing of liquids and solids. These hydrodynamic problems are illustrated in slurry reactors which constructionally may be bubble columns, stirred tanks or jet loop reactors. The expected effects are predicted by means of tests with model systems modified to represent the conditions in industrial hydrogenation reactors. In his book 'Mass Transfer in Heterogeneous Catalysis' (1970) Satterfield complained of the lack of knowledge about the design of slurry reactors and hence of the impossible task of the engineer who has to design a plant according to accepted rules. There have been no fundamental changes since then. This paper presents the problems facing the engineer in designing slurry reactors, and shows new development trends.

  12. Results For The Third Quarter 2010 Tank 50 WAC Slurry Sample: Chemical And Radionuclide Contaminant Results

    International Nuclear Information System (INIS)

    Reigel, M.; Bibler, N.

    2010-01-01

    This report details the chemical and radionuclide contaminant results for the characterization of the 2010 Third Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC). Information from this characterization will be used by Liquid Waste Operations (LWO) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System. The following conclusions are drawn from the analytical results provided in this report: (i) The concentrations of the reported chemical and radioactive contaminants were less than their respective WAC targets or limits unless noted in this section. (ii) The reported detection limits for 94 Nb, 247 Cm and 249 Cf are above the requested limits from Reference 4. However, they are below the limits established in Reference 3. (iii) The reported detection limit for 242m Am is greater than the requested limit from Attachment 8.4 of the WAC. (iv) The reported detection limit for Isopar L is greater than the limit from Table 3 of the WAC. (v) The reported concentration of Isopropanol is greater than the limit from Table 4 of the WAC. (vi) Isopar L and Norpar 13 have limited solubility in aqueous solutions making it difficult to obtain consistent and reliable sub-samples. The values reported in this memo are the concentrations in the sub-sample as detected by the GC/MS; however, the results may not accurately represent the concentrations of the analytes in Tank 50.

  13. Hydraulic Behavior and Chemical Characterization of Lapilli as Material for Natural Filtering of Slurry

    Directory of Open Access Journals (Sweden)

    Nereida Falcón-Cardona

    2015-06-01

    Full Text Available Livestock effluents are a beneficial nutrient supply for crops, whereby their use is critical to ensure the sustainability of the farms global management. However, they can cause serious ecological problems if misused, polluting soils and groundwater. Combining “soft technology” and local materials is a low cost solution in terms of finance and energy. The REAGUA project (REuso AGUA, Water reuse in Spanish analyzes the possibility of using “picon” (lapilli as a material for the treatment of liquid manure from ruminants, for later use in subsurface drip irrigation system to produce forage and biofuels, in which the soil acts as a subsequent advanced treatment. A three-phase system, in which the effluent was poured with a vertical subsurface flow in an unsaturated medium, is designed. In order to determine the management conditions that optimize the filter, it was necessary to characterize the hydraulic behavior of lapilli and its ability to remove substances. Using three lapilli-filled columns, unsaturated flux, and a ruminant effluent, the reduction of chemical oxygen demand (COD, biochemical oxygen demand after 5 days (BOD5 and ammonia, phosphorus and suspension solids (SS obtained was over 80%, 90%, and 95% respectively, assumable values for irrigation.

  14. A composite of complex and chemical hydrides yields the first Al-based amidoborane with improved hydrogen storage properties.

    Science.gov (United States)

    Dovgaliuk, Iurii; Jepsen, Lars H; Safin, Damir A; Łodziana, Zbigniew; Dyadkin, Vadim; Jensen, Torben R; Devillers, Michel; Filinchuk, Yaroslav

    2015-10-05

    The first Al-based amidoborane Na[Al(NH2 BH3 )4 ] was obtained through a mechanochemical treatment of the NaAlH4 -4 AB (AB=NH3 BH3 ) composite releasing 4.5 wt % of pure hydrogen. The same amidoborane was also produced upon heating the composite at 70 °C. The crystal structure of Na[Al(NH2 BH3 )4 ], elucidated from synchrotron X-ray powder diffraction and confirmed by DFT calculations, contains the previously unknown tetrahedral ion [Al(NH2 BH3 )4 ](-) , with every NH2 BH3 (-) ligand coordinated to aluminum through nitrogen atoms. Combination of complex and chemical hydrides in the same compound was possible due to both the lower stability of the AlH bonds compared to the BH ones in borohydride, and due to the strong Lewis acidity of Al(3+) . According to the thermogravimetric analysis-differential scanning calorimetry-mass spectrometry (TGA-DSC-MS) studies, Na[Al(NH2 BH3 )4 ] releases in two steps 9 wt % of pure hydrogen. As a result of this decomposition, which was also supported by volumetric studies, the formation of NaBH4 and amorphous product(s) of the surmised composition AlN4 B3 H(0-3.6) were observed. Furthermore, volumetric experiments have also shown that the final residue can reversibly absorb about 27 % of the released hydrogen at 250 °C and p(H2 )=150 bar. Hydrogen re-absorption does not regenerate neither Na[Al(NH2 BH3 )4 ] nor starting materials, NaAlH4 and AB, but rather occurs within amorphous product(s). Detailed studies of the latter one(s) can open an avenue for a new family of reversible hydrogen storage materials. Finally, the NaAlH4 -4 AB composite might become a starting point towards a new series of aluminum-based tetraamidoboranes with improved hydrogen storage properties such as hydrogen storage density, hydrogen purity, and reversibility. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Optimization of chemical and instrumental parameters in hydride generation laser-induced breakdown spectrometry for the determination of arsenic, antimony, lead and germanium in aqueous samples.

    Science.gov (United States)

    Yeşiller, Semira Unal; Yalçın, Serife

    2013-04-03

    A laser induced breakdown spectrometry hyphenated with on-line continuous flow hydride generation sample introduction system, HG-LIBS, has been used for the determination of arsenic, antimony, lead and germanium in aqueous environments. Optimum chemical and instrumental parameters governing chemical hydride generation, laser plasma formation and detection were investigated for each element under argon and nitrogen atmosphere. Arsenic, antimony and germanium have presented strong enhancement in signal strength under argon atmosphere while lead has shown no sensitivity to ambient gas type. Detection limits of 1.1 mg L(-1), 1.0 mg L(-1), 1.3 mg L(-1) and 0.2 mg L(-1) were obtained for As, Sb, Pb and Ge, respectively. Up to 77 times enhancement in detection limit of Pb were obtained, compared to the result obtained from the direct analysis of liquids by LIBS. Applicability of the technique to real water samples was tested through spiking experiments and recoveries higher than 80% were obtained. Results demonstrate that, HG-LIBS approach is suitable for quantitative analysis of toxic elements and sufficiently fast for real time continuous monitoring in aqueous environments. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Slurry explosives

    Energy Technology Data Exchange (ETDEWEB)

    1973-08-23

    A slurry explosive is comprised of (1) a composition consisting of ammonium nitrate or a mixture of ammonium nitrate and an alkali metal nitrate; or an alkaline earth metal nitrate; or an alkali metal nitrate and an alkaline earth metal nitrate; at least one member selected from the group consisting of 2,4,6-trinitrotoluene, aluminum, smokeless powder and fuels; and water; (2) 0.1 to 2.0% of guar gum; (3) between 0% and 0.3% of a sodium, potassium, calcium or magnesium borate; and greater than 0% but not more than 20% of hexamethylene tetramine; and (4) 0.02 to 2.0% of antimony potassium tartarate, antimony trioxide, antimony trisulfide or a mixture of these antimony compounds, % by wt.

  17. Nanostructured, complex hydride systems for hydrogen generation

    Directory of Open Access Journals (Sweden)

    Robert A. Varin

    2015-02-01

    Full Text Available Complex hydride systems for hydrogen (H2 generation for supplying fuel cells are being reviewed. In the first group, the hydride systems that are capable of generating H2 through a mechanical dehydrogenation phenomenon at the ambient temperature are discussed. There are few quite diverse systems in this group such as lithium alanate (LiAlH4 with the following additives: nanoiron (n-Fe, lithium amide (LiNH2 (a hydride/hydride system and manganese chloride MnCl2 (a hydride/halide system. Another hydride/hydride system consists of lithium amide (LiNH2 and magnesium hydride (MgH2, and finally, there is a LiBH4-FeCl2 (hydride/halide system. These hydride systems are capable of releasing from ~4 to 7 wt.% H2 at the ambient temperature during a reasonably short duration of ball milling. The second group encompasses systems that generate H2 at slightly elevated temperature (up to 100 °C. In this group lithium alanate (LiAlH4 ball milled with the nano-Fe and nano-TiN/TiC/ZrC additives is a prominent system that can relatively quickly generate up to 7 wt.% H2 at 100 °C. The other hydride is manganese borohydride (Mn(BH42 obtained by mechano-chemical activation synthesis (MCAS. In a ball milled (2LiBH4 + MnCl2 nanocomposite, Mn(BH42 co-existing with LiCl can desorb ~4.5 wt.% H2 at 100 °C within a reasonable duration of dehydrogenation. Practical application aspects of hydride systems for H2 generation/storage are also briefly discussed.

  18. Estimation of nutrients and organic matter in Korean swine slurry using multiple regression analysis of physical and chemical properties.

    Science.gov (United States)

    Suresh, Arumuganainar; Choi, Hong Lim

    2011-10-01

    Swine waste land application has increased due to organic fertilization, but excess application in an arable system can cause environmental risk. Therefore, in situ characterizations of such resources are important prior to application. To explore this, 41 swine slurry samples were collected from Korea, and wide differences were observed in the physico-biochemical properties. However, significant (Phydrometer, EC meter, drying oven and pH meter were found useful to estimate Mn, Fe, Ca, K, Al, Na, N and 5-day biochemical oxygen demands (BOD₅) at improved R² values of 0.83, 0.82, 0.77, 0.75, 0.67, 0.47, 0.88 and 0.70, respectively. The results from this study suggest that multiple property regressions can facilitate the prediction of micronutrients and organic matter much better than a single property regression for livestock waste. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Investigation of chemical modifiers for the determination of lead in fertilizers and limestone using graphite furnace atomic absorption spectrometry with Zeeman-effect background correction and slurry sampling

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Aline R. [Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciência e Tecnologia do CNPq–INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Becker, Emilene M.; Dessuy, Morgana B. [Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil); Vale, Maria Goreti R., E-mail: mgrvale@ufrgs.br [Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciência e Tecnologia do CNPq–INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Welz, Bernhard [Instituto Nacional de Ciência e Tecnologia do CNPq–INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Departamento de Química, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil)

    2014-02-01

    In this work, chemical modifiers in solution (Pd/Mg, NH{sub 4}H{sub 2}PO{sub 4} and NH{sub 4}NO{sub 3}/Pd) were compared with permanent modifiers (Ir and Ru) for the determination of lead in fertilizer and limestone samples using slurry sampling and graphite furnace atomic absorption spectrometry with Zeeman-effect background correction. The analytical line at 283.3 nm was used due to some spectral interference observed at 217.0 nm. The NH{sub 4}H{sub 2}PO{sub 4} was abandoned due to severe spectral interference even at the 283.3-nm line. For Pd/Mg and NH{sub 4}NO{sub 3}/Pd the optimum pyrolysis and atomization temperatures were 900 °C and 1900 °C, respectively. For Ru and Ir, the integrated absorbance signal was stable up to pyrolysis temperatures of 700 °C and 900 °C, respectively, and up to atomization temperature of 1700 °C. The limit of detection (LOD) was 17 ng g{sup −1} using Pd/Mg and 29 ng g{sup −1} using NH{sub 4}NO{sub 3}/Pd. Among the permanent modifiers investigated, the LOD was 22 ng g{sup −1} Pb for Ir and 10 ng g{sup −1} Pb for Ru. The accuracy of the method was evaluated using the certified reference material NIST SRM 695. Although Ru provided lower LOD, which can be attributed to a lower blank signal, only the modifiers in solution showed concordant values of Pb concentration for the NIST SRM 695 and the most of analyzed samples. Moreover, the Pd/Mg modifier provided the highest sensitivity and for this reason it is more suitable for the determination of Pb in fertilizers samples in slurry; besides this it presented a better signal-to-noise ratio than NH{sub 4}NO{sub 3}/Pd. - Highlights: • Lead has been determined in fertilizers using slurry sampling GF AAS. • The mixture of palladium and magnesium nitrates was found to be the ideal chemical modifier. • Calibration could be carried out against aqueous standard solutions. • The proposed method is much faster than the EPA method, which includes sample digestion.

  20. Study of a new hybrid process combining slurry infiltration and Reactive Chemical Vapour Infiltration for the realisation of Ceramic Matrix Composites

    International Nuclear Information System (INIS)

    Ledain, Olivier

    2014-01-01

    Ceramic matrix composites were originally developed for aerospace,military aeronautics or energy applications thanks to their good properties at high temperature. They are generally made by Chemical Vapor Infiltration (CVI). A new short hybrid process combining fiber preform slurry impregnation of ceramic powders with an innovative Reactive CVI (RCVI) route is proposed to reduce the production time. This route is based on the combination of Reactive Chemical Vapour Deposition (RCVD), which is often used to deposit coatings on fibres, with the Chemical Vapor Infiltration (CVI).In RCVD, the absence of one element of the deposited carbide in the initial gas phase involves the consumption/conversion of the solid substrate. In this work, the RCVD growth and the associated consumption were studied with different parameters in the Ti-H-Cl-C chemical system. The study has been completed with the chemical products analysis, combining XRD, XPS and FTIR. Then, the partial conversion of sub-micrometer carbon powders into titanium carbide and the consolidation of green bodies by RCVI from H 2 /TiCl 4 gaseous infiltration were studied. The residual porosity and the final TiC content were measured in the bulk of the infiltrated powders by image analysis from scanning electron microscopy. Depending on temperature, few hundred micrometers-depth infiltrations are obtained.Finally, the results have been transposed to the RCVI into CMC-type pre-forms. Despite a minimal TiC content of 25% in the overall preform, the results shown a bad homogeneity of the infiltration and a poor cohesion of fibres with RCVI consolidated powder of their environment. (author) [fr

  1. Effects of K3[Fe(CN)6] slurry's pH value and applied potential on tungsten removal rate for chemical-mechanical planarization application

    Energy Technology Data Exchange (ETDEWEB)

    Akonko, S.B.; Li, D.Y.; Ziomek-Moroz, M.; Hawk, J.A.; Miller, A.; Cadien, K.

    2005-07-01

    Chemical-mechanical planarization (CMP) is an important process for building multilevel interconnections for electronic devices. Directly planarizing tungsten, which is used as via or contact in microelectronic circuits, by wear is a difficult process because of its high hardness. Therefore, an effective approach has been developed to facilitate planarizing tungsten surface by removing a continuously growing passive film on tungsten when exposed to a low-pH potassium ferricyanide slurry. Since the passive film is softer than tungsten, this chemical mechanical planarization process is effective. In this work, in order to determine effects of corrosion and wear on tungsten removal rate, attempts were made to investigate corrosion, wear, and corrosive wear behavior of tungsten in K3[Fe(CN)6] slurries. Electrochemical and tribological experiments were carried out for different slurry pH values and potentials using a rotating pin-on-disc tribometer. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were employed to characterize surface films formed at the different pH levels and potentials. It was demonstrated that the tungsten removal rate increased with increasing slurry pH and potential. Mechanisms involved are discussed.

  2. Final Technical Report for GO15052 Intematix: Combinatorial Synthesis and High Throughput Screening of Effective Catalysts for Chemical Hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Melman, Jonathan [Intematix Corporation, Fremont, CA (United States)

    2017-02-22

    The objectives of this project are: to discover cost-effective catalysts for release of hydrogen from chemical hydrogen storage systems; and to discover cost-effective catalysts for the regeneration of spent chemical hydrogen storage materials.

  3. The effects of a spray slurry nozzle on copper CMP for reduction in slurry consumption

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Da Sol; Jeong, Hae Do [Pusan National University, Busan (Korea, Republic of); Lee, Hyun Seop [Tongmyong University, Busan (Korea, Republic of)

    2015-12-15

    The environmental impact of semiconductor manufacturing has been a big social problem, like greenhouse gas emission. Chemical mechanical planarization (CMP), a wet process which consumes chemical slurries, seriously impacts environmental sustain ability and cost-effectiveness. This paper demonstrates the superiority of a full-cone spray slurry nozzle to the conventional tube-type slurry nozzle in Cu CMP. It was observed that the spray nozzle made a weak slurry wave at the retaining ring unlike a conventional nozzle, because the slurry was supplied uniformly in broader areas. Experiments were implemented with different slurry flow rates and spray nozzle heights. Spray nozzle performance is controlled by the spray angle and spray height. The process temperature was obtained with an infrared (IR) sensor and an IR thermal imaging camera to investigate the cooling effect of the spray. The results show that the spray nozzle provides a higher Material removal rate (MRR), lower non-uniformity (NU), and lower temperature than the conventional nozzle. Computational fluid dynamics techniques show that the turbulence kinetic energy and slurry velocity of the spray nozzle are much higher than those of the conventional nozzle. Finally, it can be summarized that the spray nozzle plays a significant role in slurry efficiency by theory of Minimum quantity lubrication (MQL).

  4. The effects of a spray slurry nozzle on copper CMP for reduction in slurry consumption

    International Nuclear Information System (INIS)

    Lee, Da Sol; Jeong, Hae Do; Lee, Hyun Seop

    2015-01-01

    The environmental impact of semiconductor manufacturing has been a big social problem, like greenhouse gas emission. Chemical mechanical planarization (CMP), a wet process which consumes chemical slurries, seriously impacts environmental sustain ability and cost-effectiveness. This paper demonstrates the superiority of a full-cone spray slurry nozzle to the conventional tube-type slurry nozzle in Cu CMP. It was observed that the spray nozzle made a weak slurry wave at the retaining ring unlike a conventional nozzle, because the slurry was supplied uniformly in broader areas. Experiments were implemented with different slurry flow rates and spray nozzle heights. Spray nozzle performance is controlled by the spray angle and spray height. The process temperature was obtained with an infrared (IR) sensor and an IR thermal imaging camera to investigate the cooling effect of the spray. The results show that the spray nozzle provides a higher Material removal rate (MRR), lower non-uniformity (NU), and lower temperature than the conventional nozzle. Computational fluid dynamics techniques show that the turbulence kinetic energy and slurry velocity of the spray nozzle are much higher than those of the conventional nozzle. Finally, it can be summarized that the spray nozzle plays a significant role in slurry efficiency by theory of Minimum quantity lubrication (MQL).

  5. Determination of Cd, Hg, Pb and Se in sediments slurries by isotopic dilution calibration ICP-MS after chemical vapor generation using an on-line system or retention in an electrothermal vaporizer treated with iridium

    International Nuclear Information System (INIS)

    Vieira, Mariana Antunes; Ribeiro, Anderson Schwingel; Dias, Lucia Felicidade; Curtius, Adilson Jose

    2005-01-01

    A method for the determination of Cd, Hg, Pb and Se in sediments reference materials by slurry sampling chemical vapor generation (CVG) using isotopic dilution (ID) calibration and detection by inductively coupled plasma mass spectrometry (ICP-MS) is proposed. Two different systems were used for the investigation: an on-line flow injection system (FI-CVG-ICP-MS) and an off-line system with in situ trapping electrothermal vaporization (CVG-ETV-ICP-MS). About 100 mg of the reference material, ground to a particle size ≤50 μm, was mixed with acid solutions (aqua regia, HF and HCl) in an ultrasonic bath. The enriched isotopes 111 Cd, 198 Hg, 206 Pb and 77 Se were then added to the slurry in an adequate amount in order to produce an altered isotopic ratio close to 1. For the on-line system, a standing time for the slurry of 12 h before measurement was required, while for the batch system, no standing time is needed to obtain accurate results. The conditions for the formation of the analyte vapor were optimized for the evaluated systems. The following altered isotope ratios were measured: 111 Cd/ 114 Cd, 198 Hg/ 199 Hg, 206 Pb/ 208 Pb e 77 Se/ 82 Se. The obtained detection limits in the on-line system, in μg g -1 , were: Cd: 0.15; Hg: 0.09; Pb: 6.0 and Se: 0.03. Similar detection limits were obtained with the system that uses the ETV: 0.21 for Hg, 6.0 for Pb and 0.06 μg g -1 for Se. No signal for Cd was obtained in this system. One estuarine, two marine and two river certified sediments were analyzed to check the accuracy. The obtained values by both systems were generally in agreement with the certified concentrations, according to the t-test for a confidence level of 95%, demonstrating that isotope equilibration was attained in the slurries submitted to a chemical vapor generation procedure and detection by ICP-MS. The relative standard deviations were lower than 10%, adequate for slurry analysis. The almost quantitative analytes extractions to the aqueous phase

  6. Predicting transport requirements for radioactive-waste slurries

    International Nuclear Information System (INIS)

    Motyka, T.; Randall, C.T.

    1983-01-01

    A method for predicting the transport requirements of radioactive waste slurries was developed. This method involved preparing nonradioactive sludge slurries chemically similar to the actual high-level waste. The rheological and settling characteristics of these synthetic waste slurries were measured and found to compare favorably with data on actual defense waste slurries. Pressure drop versus flow rate data obtained fom a 2-in. slurry test loop confirmed the Bingham plastic behavior of the slurry observed during viscometry measurements. The pipeline tests, however, yielded friction factors 30 percent lower than those predicted from viscometry data. Differences between the sets of data were attributed to inherent problems in interpreting accurate yield-stress values of slurry suspensions with Couette-type viscometers. Equivalent lengths of fittings were also determined and found to be less than that of water at a specified flow rate

  7. Hydride Molecules towards Nearby Galaxies

    Science.gov (United States)

    Monje, Raquel R.; La, Ngoc; Goldsmith, Paul

    2018-06-01

    Observations carried out by the Herschel Space Observatory revealed strong spectroscopic signatures from light hydride molecules within the Milky Way and nearby active galaxies. To better understand the chemical and physical conditions of the interstellar medium, we conducted the first comprehensive survey of hydrogen fluoride (HF) and water molecular lines observed through the SPIRE Fourier Transform Spectrometer. By collecting and analyzing the sub-millimeter spectra of over two hundred sources, we found that the HF J = 1 - 0 rotational transition which occurs at approximately 1232 GHz was detected in a total of 39 nearby galaxies both in absorption and emission. The analysis will determine the main excitation mechanism of HF in nearby galaxies and provide steady templates of the chemistry and physical conditions of the ISM to be used in the early universe, where observations of hydrides are more scarce.

  8. Ice slurry applications

    Energy Technology Data Exchange (ETDEWEB)

    Kauffeld, M. [Karlsruhe University of Applied Sciences, Moltkestr. 30, 76133 Karlsruhe (Germany); Wang, M.J.; Goldstein, V. [Sunwell Technologies Inc., 180 Caster Avenue, Woodbridge, L4L 5Y (Canada); Kasza, K.E. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

    2010-12-15

    The role of secondary refrigerants is expected to grow as the focus on the reduction of greenhouse gas emissions increases. The effectiveness of secondary refrigerants can be improved when phase changing media are introduced in place of single-phase media. Operating at temperatures below the freezing point of water, ice slurry facilitates several efficiency improvements such as reductions in pumping energy consumption as well as lowering the required temperature difference in heat exchangers due to the beneficial thermo-physical properties of ice slurry. Research has shown that ice slurry can be engineered to have ideal ice particle characteristics so that it can be easily stored in tanks without agglomeration and then be extractable for pumping at very high ice fraction without plugging. In addition ice slurry can be used in many direct contact food and medical protective cooling applications. This paper provides an overview of the latest developments in ice slurry technology. (author)

  9. Effects of Combined Application of Biogas Slurry and Chemical Fertilizer on Soil Aggregation and C/N Distribution in an Ultisol

    Science.gov (United States)

    Zheng, Xuebo; Fan, Jianbo; Xu, Lei; Zhou, Jing

    2017-01-01

    Unreasonable use of chemical fertilizer (CF) on agricultural soil leads to massive losses of soil organic carbon (SOC) and total nitrogen (TN) in tropical and subtropical areas, where soil conditions are unfavorable for aggregate formation. This study evaluated the effects of combined application of biogas slurry (BS) plus CF on soil aggregation and aggregate—associated C/N concentration and storage in an Ultisol. Six treatments included: no fertilizer (T1), CF only (T2), partial (15% (T3), 30% (T4) and 45% (T5)) substitution of TN with BS and BS only (T6). Soil mechanical—stable aggregates (MSAs) formation and stability as well as MSAs—associated C/N concentration and storage were observed in different aggregate sizes (>5, 5–2, 2–1, 1.0–0.5, 0.50–0.25 and 5 mm significantly increased with BS substitution (T5), while the proportions of MSAs 1.0–0.5 mm, MSAs 0.50–0.25 mm and MSAs 0.5 mm that constituted 72–82% of MSAs. Stepwise regression analysis showed that MSAs >5 mm, SOC in MSAs >5 mm and TN in MSAs >5 mm were the dominant variables affecting aggregate stability. Meanwhile SOC in MSAs <0.25 mm and TN in MSAs 2–1 mm were independent variables affecting SOC and TN concentrations in bulk soils. Therefore, certain rate of combined application of BS plus CF is an effective, eco—friendly way to improve soil quality in an Ultisol. PMID:28125647

  10. Preparation of beryllium hydride

    International Nuclear Information System (INIS)

    Roberts, C.B.

    1975-01-01

    A process is described for preparing beryllium hydride by the direct reaction of beryllium borohydride and aluminum hydride trimethylamine adduct. Volatile by-products and unreacted reactants are readily removed from the product mass by sublimation and/or evaporation. (U.S.)

  11. Predicting formation enthalpies of metal hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Andreasen, A.

    2004-12-01

    In order for the hydrogen based society viz. a society in which hydrogen is the primary energy carrier to become realizable an efficient way of storing hydrogen is required. For this purpose metal hydrides are serious candidates. Metal hydrides are formed by chemical reaction between hydrogen and metal and for the stable hydrides this is associated with release of heat ({delta}H{sub f} ). The more thermodynamically stable the hydride, the larger {delta}H{sub f}, and the higher temperature is needed in order to desorp hydrogen (reverse reaction) and vice versa. For practical application the temperature needed for desorption should not be too high i.e. {delta}H{sub f} should not be too large. If hydrogen desorption is to be possible below 100 deg C (which is the ultimate goal if hydrogen storage in metal hydrides should be used in conjunction with a PEM fuel cell), {delta}H{sub f} should not exceed -48 kJ/mol. Until recently only intermetallic metal hydrides with a storage capacity less than 2 wt.% H{sub 2} have met this criterion. However, discovering reversible hydrogen storage in complex metal hydrides such as NaAlH{sub 4} (5.5 wt. % reversible hydrogen capacity) have revealed a new group of potential candiates. However, still many combination of elements from the periodic table are yet to be explored. Since experimental determination of thermodynamic properties of the vast combinations of elements is tedious it may be advantagous to have a predictive tool for this task. In this report different ways of predicting {delta}H{sub f} for binary and ternary metal hydrides are reviewed. Main focus will be on how well these methods perform numerically i.e. how well experimental results are resembled by the model. The theoretical background of the different methods is only briefly reviewed. (au)

  12. Slurry pipeline design approach

    Energy Technology Data Exchange (ETDEWEB)

    Betinol, Roy; Navarro R, Luis [Brass Chile S.A., Santiago (Chile)

    2009-12-19

    Compared to other engineering technologies, the design of a commercial long distance Slurry Pipeline design is a relatively new engineering concept which gained more recognition in the mid 1960 's. Slurry pipeline was first introduced to reduce cost in transporting coal to power generating units. Since then this technology has caught-up worldwide to transport other minerals such as limestone, copper, zinc and iron. In South America, the use of pipeline is commonly practiced in the transport of Copper (Chile, Peru and Argentina), Iron (Chile and Brazil), Zinc (Peru) and Bauxite (Brazil). As more mining operations expand and new mine facilities are opened, the design of the long distance slurry pipeline will continuously present a commercially viable option. The intent of this paper is to present the design process and discuss any new techniques and approach used today to ensure a better, safer and economical slurry pipeline. (author)

  13. Overview of slurry pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Gandhi, R L

    1982-01-01

    Slurry pipelines have proven to be a technically feasible, environmentally attractive and economic method of transporting finely divided particles over long distances. A pipeline system normally consists of preparation, pipeline and utilization facilities and requires optimization of all three components taken together. A considerable amount of research work has been done to develop hydraulic design of a slurry pipeline. Equipment selection and estimation of corrosion-erosion are considered to be as important as the hydraulic design. Future applications are expected to be for the large-scale transport of coal and for the exploitation of remotely located mineral deposits such as iron ore and copper. Application of slurry pipelines for the exploitation of remotely located mineral deposits is illustrated by the Kudremukh iron concentrate slurry pipeline in India.

  14. Regenerative Hydride Heat Pump

    Science.gov (United States)

    Jones, Jack A.

    1992-01-01

    Hydride heat pump features regenerative heating and single circulation loop. Counterflow heat exchangers accommodate different temperatures of FeTi and LaNi4.7Al0.3 subloops. Heating scheme increases efficiency.

  15. Alkali metal hydride formation

    International Nuclear Information System (INIS)

    1976-01-01

    The present invention relates to a method of producing alkali metal hydrides by absorbing hydrogen gas under pressure into a mixture of lower alkyl mono amines and alkali metal alkyl amides selected from sodium and potassium amides formed from said amines. The present invention also includes purification of a mixture of the amines and amides which contain impurities, such as is used as a catalytic exchange liquid in the enrichment of deuterium, involving the formation of the alkali metal hydride

  16. Blistering and hydride embrittlement

    International Nuclear Information System (INIS)

    Louthan, M.R. Jr.

    1975-01-01

    The effects of hydrogen on the mechanical properties of metals have been categorized into several groups. Two of the groups, hydrogen blistering and hydride embrittlement, are reasonably well understood, and problems relating to their occurrence may be avoided if that understanding is used as a basis for selecting alloys for hydrogen service. Blistering and hydride embrittlement are described along with several techniques of materials selection and used to minimize their adverse effects. (U.S.)

  17. Rheological properties of defense waste slurries

    International Nuclear Information System (INIS)

    Ebadian, M.A.

    1998-01-01

    The major objective of this two-year project has been to obtain refined and reliable experimental data about the rheological properties of melter feeds. The research has involved both experimental studies and model development. Two experimental facilities have been set up to measure viscosity and pressure drop. Mathematical models have been developed as a result of experimental observation and fundamental rheological theory. The model has the capability to predict the viscosity of melter slurries in a range of experimental conditions. The final results of the investigation could be used to enhance the current design base for slurry transportation systems and improve the performance of the slurry mixing process. If successful, the cost of this waste treatment will be reduced, and disposal safety will be increased. The specific objectives for this project included: (1) the design, implementation, and validation of the experimental facility in both batch and continuous operating modes; (2) the identification and preparation of melter feed samples of both the SRS and Hanford waste slurries at multiple solids concentration levels; (3) the measurement and analysis of the melter feeds to determine the effects of the solids concentration, pH value, and other factors on the rheological properties of the slurries; (4) the correlation of the rheological properties as a function of the measured physical and chemical parameters; and (5) transmission of the experimental data and resulting correlation to the DOE site user to guide melter feed preparation and transport equipment design

  18. Slurry sampling flow injection chemical vapor generation inductively coupled plasma mass spectrometry for the determination of trace Ge, As, Cd, Sb, Hg and Bi in cosmetic lotions

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Wei-Ni [Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan (China); Jiang, Shiuh-Jen, E-mail: sjjiang@faculty.nsysu.edu.tw [Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan (China); Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Chen, Yen-Ling [Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Sahayam, A.C. [National Centre for Compositional Characterisation of Materials (CCCM), Hyderabad (India)

    2015-02-20

    Highlights: • Determination of Ge, As, Cd, Sb, Hg and Bi in cosmetic lotions in a single run. • Accurate analysis using isotope dilution and standard addition methods. • Vapor generation ICP-MS yielded superior detection limits compared to ETV-ICP-MS. • No sample dissolution increased sample through put. • Analysis of GBW09305 Cosmetic (Cream) reference material for accuracy. - Abstract: A slurry sampling inductively coupled plasma mass spectrometry (ICP-MS) method has been developed for the determination of Ge, As, Cd, Sb, Hg and Bi in cosmetic lotions using flow injection (FI) vapor generation (VG) as the sample introduction system. A slurry containing 2% m/v lotion, 2% m/v thiourea, 0.05% m/v L-cysteine, 0.5 μg mL{sup −1} Co(II), 0.1% m/v Triton X-100 and 1.2% v/v HCl was injected into a VG-ICP-MS system for the determination of Ge, As, Cd, Sb, Hg and Bi without dissolution and mineralization. Because the sensitivities of the analytes in the slurry and that of aqueous solution were quite different, an isotope dilution method and a standard addition method were used for the determination. This method has been validated by the determination of Ge, As, Cd, Sb, Hg and Bi in GBW09305 Cosmetic (Cream) reference material. The method was also applied for the determination of Ge, As, Cd, Sb, Hg and Bi in three cosmetic lotion samples obtained locally. The analysis results of the reference material agreed with the certified value and/or ETV-ICP-MS results. The detection limit estimated from the standard addition curve was 0.025, 0.1, 0.2, 0.1, 0.15, and 0.03 ng g{sup −1} for Ge, As, Cd, Sb, Hg and Bi, respectively, in original cosmetic lotion sample.

  19. Slurry sampling flow injection chemical vapor generation inductively coupled plasma mass spectrometry for the determination of trace Ge, As, Cd, Sb, Hg and Bi in cosmetic lotions

    International Nuclear Information System (INIS)

    Chen, Wei-Ni; Jiang, Shiuh-Jen; Chen, Yen-Ling; Sahayam, A.C.

    2015-01-01

    Highlights: • Determination of Ge, As, Cd, Sb, Hg and Bi in cosmetic lotions in a single run. • Accurate analysis using isotope dilution and standard addition methods. • Vapor generation ICP-MS yielded superior detection limits compared to ETV-ICP-MS. • No sample dissolution increased sample through put. • Analysis of GBW09305 Cosmetic (Cream) reference material for accuracy. - Abstract: A slurry sampling inductively coupled plasma mass spectrometry (ICP-MS) method has been developed for the determination of Ge, As, Cd, Sb, Hg and Bi in cosmetic lotions using flow injection (FI) vapor generation (VG) as the sample introduction system. A slurry containing 2% m/v lotion, 2% m/v thiourea, 0.05% m/v L-cysteine, 0.5 μg mL −1 Co(II), 0.1% m/v Triton X-100 and 1.2% v/v HCl was injected into a VG-ICP-MS system for the determination of Ge, As, Cd, Sb, Hg and Bi without dissolution and mineralization. Because the sensitivities of the analytes in the slurry and that of aqueous solution were quite different, an isotope dilution method and a standard addition method were used for the determination. This method has been validated by the determination of Ge, As, Cd, Sb, Hg and Bi in GBW09305 Cosmetic (Cream) reference material. The method was also applied for the determination of Ge, As, Cd, Sb, Hg and Bi in three cosmetic lotion samples obtained locally. The analysis results of the reference material agreed with the certified value and/or ETV-ICP-MS results. The detection limit estimated from the standard addition curve was 0.025, 0.1, 0.2, 0.1, 0.15, and 0.03 ng g −1 for Ge, As, Cd, Sb, Hg and Bi, respectively, in original cosmetic lotion sample

  20. Slurry walls and slurry trenches - construction quality control

    International Nuclear Information System (INIS)

    Poletto, R.J.; Good, D.R.

    1997-01-01

    Slurry (panel) walls and slurry trenches have become conventional methods for construction of deep underground structures, interceptor trenches and hydraulic (cutoff) barriers. More recently polymers mixed with water are used to stabilize the excavation instead of bentonite slurry. Slurry walls are typically excavated in short panel segments, 2 to 7 m (7 to 23 ft) long, and backfilled with structural materials; whereas slurry trenches are fairly continuous excavations with concurrent backfilling of blended soils, or cement-bentonite mixtures. Slurry trench techniques have also been used to construct interceptor trenches. Currently no national standards exist for the design and/or construction of slurry walls/trenches. Government agencies, private consultants, contractors and trade groups have published specifications for construction of slurry walls/trenches. These specifications vary in complexity and quality of standards. Some place excessive emphasis on the preparation and control of bentonite or polymer slurry used for excavation, with insufficient emphasis placed on quality control of bottom cleaning, tremie concrete, backfill placement or requirements for the finished product. This has led to numerous quality problems, particularly with regard to identification of key depths, bottom sediments and proper backfill placement. This paper will discuss the inspection of slurry wall/trench construction process, identifying those areas which require special scrutiny. New approaches to inspection of slurry stabilized excavations are discussed

  1. Preparation of beryllium hydride

    International Nuclear Information System (INIS)

    Lowrance, B.R.

    1975-01-01

    A process is described for the preparation of beryllium hydride which comprises pyrolyzing, while in solution in a solvent inert under the reaction conditions, with respect to reactants and products and at a temperature in the range of about 100 0 to about 200 0 C, sufficient to result in the formation of beryllium hydride, a di-t-alkyl beryllium etherate wherein each tertiary alkyl radical contains from 4 to 20 carbon atoms. The pyrolysis is carried out under an atmosphere inert under the reaction conditions, with respect to reactants and products. (U.S.)

  2. Electronic structure of ternary hydrides based on light elements

    Energy Technology Data Exchange (ETDEWEB)

    Orgaz, E. [Departamento de Fisica y Quimica Teorica, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, CP 04510 Coyoacan, Mexico, D.F. (Mexico)]. E-mail: orgaz@eros.pquim.unam.mx; Membrillo, A. [Departamento de Fisica y Quimica Teorica, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, CP 04510 Coyoacan, Mexico, D.F. (Mexico); Castaneda, R. [Departamento de Fisica y Quimica Teorica, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, CP 04510 Coyoacan, Mexico, D.F. (Mexico); Aburto, A. [Departamento de Fisica, Facultad de Ciencias, Universidad Nacional Autonoma de Mexico, CP 04510 Coyoacan, Mexico, D.F. (Mexico)

    2005-12-08

    Ternary hydrides based on light elements are interesting owing to the high available energy density. In this work we focused into the electronic structure of a series of known systems having the general formula AMH{sub 4}(A=Li,Na,M=B,Al). We computed the energy bands and the total and partial density of states using the linear-augmented plane waves method. In this report, we discuss the chemical bonding in this series of complex hydrides.

  3. Electrolytic hydriding and hydride distribution in zircaloy-4

    International Nuclear Information System (INIS)

    Gomes, M.H.L.

    1974-01-01

    A study has been made of the electrolytic hydriding of zircaloy-4 in the range 20-80 0 C, for reaction times from 5 to 30 hours, and the effect of potential, pH and dissolved oxygen has been investigated. The hydriding reaction was more sensitive to time and temperature conditions than to the electrochemical variables. It has been shown that a controlled introduction of hydrides in zircaloy is feasible. Hydrides were found to be plate like shaped and distributed mainly along grain-boundaries. It has been shown that hydriding kinetics do not follow a simple law but may be described by a Johnson-Mehl empirical equation. On the basis of this equation an activation energy of 9.400 cal/mol has been determined, which is close to the activation energy for diffusion of hydrogen in the hydride. (author)

  4. System and method for slurry handling

    Science.gov (United States)

    Steele, Raymond Douglas; Oppenheim, Judith Pauline

    2015-12-29

    A system includes a slurry depressurizing system that includes a liquid expansion system configured to continuously receive a slurry at a first pressure and continuously discharge the slurry at a second pressure. For example, the slurry depressurizing system may include an expansion turbine to expand the slurry from the first pressure to the second pressure.

  5. Quantum-chemical study of structure and stability of hydride complexes Li4BeH6 and Li4MgH6

    International Nuclear Information System (INIS)

    Zyubin, A.S.; Charkin, O.P.; Klabo, D.A.; Shlojfer, P.R.

    1993-01-01

    Nonempirical calculations of geometrical structure, electronic structure and relative energies of a wide range of different configurations of Li 4 MH 6 (M = Be, Mg) molecules were conducted in order to predict the existence of complex hydrides with high hydrogen content. It was revealed, that Li 4 MH 6 molecules were stable to decomposition and could exist in isolated state or in inert matrices. Li 4 MH 6 systems are noted for existence of several isomers with energy, close to the basic structure. The presence of M atoms with coordination number (CN) equal to four is considered to be their common feature. The structure, where CN of Be and Mg is equal to three, are less stable. Configurations, including M atoms with CN = 5 or 6, are much more unfavorable from the viewpoint of energy

  6. Electronic structure, bonding and chemisorption in metallic hydrides

    International Nuclear Information System (INIS)

    Ward, J.W.

    1980-01-01

    Problems that can arise during the cycling steps for a hydride storage system usually involve events at surfaces. Chemisorption and reaction processes can be affected by small amounts of contaminants that may act as catalytic poisons. The nature of the poisoning process can vary greatly for the different metals and alloys that form hydrides. A unifying concept is offered, which satisfactorily correlates many of the properties of transition-metal, rare-earth and actinide hydrides. The metallic hydrides can be differentiated on the basis of electronegativity, metallic radius (valence) and electronic structure. For those systems where there are d (transition metals) or f (early actinides) electrons near the Fermi level a broad range of chemical and catalytic behaviors are found, depending on bandwidth and energy. The more electropositive metals (rare-earths, actinides, transition metals with d > 5) dissolve hydrogen and form hydrides by an electronically somewhat different process, and as a class tend to adsorb electrophobic molecules. The net charge-transfer in either situation is subtle; however, the small differences are responsible for many of the observed structural, chemical, and catalytic properties in these hydride systems

  7. Preparation of beryllium hydride

    International Nuclear Information System (INIS)

    Bergeron, C.R.; Baker, R.W.

    1975-01-01

    Beryllium hydride of high bulk density, suitable for use as a component of high-energy fuels, is prepared by the pyrolysis, in solution in an inert solvent, of a ditertiary-alkyl beryllium. An agitator introduces mechanical energy into the reaction system, during the pyrolysis, at the rate of 0.002 to 0.30 horsepower per gallon of reaction mixture. (U.S.)

  8. Air and metal hydride battery

    Energy Technology Data Exchange (ETDEWEB)

    Lampinen, M.; Noponen, T. [Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Applied Thermodynamics

    1998-12-31

    The main goal of the air and metal hydride battery project was to enhance the performance and manufacturing technology of both electrodes to such a degree that an air-metal hydride battery could become a commercially and technically competitive power source for electric vehicles. By the end of the project it was possible to demonstrate the very first prototype of the air-metal hydride battery at EV scale, achieving all the required design parameters. (orig.)

  9. Hydriding of metallic thorium

    International Nuclear Information System (INIS)

    Miyake, Masanobu; Katsura, Masahiro; Matsuki, Yuichi; Uno, Masayoshi

    1983-01-01

    Powdered thorium is usually prepared through a combination of hydriding and dehydriding processes of metallic thorium in massive form, in which the hydriding process consists of two steps: the formation of ThH 2 , and the formation of Th 4 H 15 . However, little has yet been known as to on what stage of hydriding process the pulverization takes place. It is found in the present study that the formation of Th 4 H 15 by the reaction of ThH 2 with H 2 is responsible for pulverization. Temperature of 70 deg C adopted in this work for the reaction of formation Th 4 H 15 seems to be much more effective for production of powdered thorium than 200 - 300 deg C in the literature. The pressure-composition-temperature relationships for Th-H system are determined at 200, 300, 350, and 800 deg C. From these results, a tentative equilibrium phase diagram for the Th-H system is proposed, attention being focused on the two-phase region of ThH 2 and Th 4 H 15 . Pulverization process is discussed in terms of the tentative phase diagram. (author)

  10. Hydrogen Outgassing from Lithium Hydride

    Energy Technology Data Exchange (ETDEWEB)

    Dinh, L N; Schildbach, M A; Smith, R A; Balazs1, B; McLean II, W

    2006-04-20

    Lithium hydride is a nuclear material with a great affinity for moisture. As a result of exposure to water vapor during machining, transportation, storage and assembly, a corrosion layer (oxide and/or hydroxide) always forms on the surface of lithium hydride resulting in the release of hydrogen gas. Thermodynamically, lithium hydride, lithium oxide and lithium hydroxide are all stable. However, lithium hydroxides formed near the lithium hydride substrate (interface hydroxide) and near the sample/vacuum interface (surface hydroxide) are much less thermally stable than their bulk counterpart. In a dry environment, the interface/surface hydroxides slowly degenerate over many years/decades at room temperature into lithium oxide, releasing water vapor and ultimately hydrogen gas through reaction of the water vapor with the lithium hydride substrate. This outgassing can potentially cause metal hydriding and/or compatibility issues elsewhere in the device. In this chapter, the morphology and the chemistry of the corrosion layer grown on lithium hydride (and in some cases, its isotopic cousin, lithium deuteride) as a result of exposure to moisture are investigated. The hydrogen outgassing processes associated with the formation and subsequent degeneration of this corrosion layer are described. Experimental techniques to measure the hydrogen outgassing kinetics from lithium hydride and methods employing the measured kinetics to predict hydrogen outgassing as a function of time and temperature are presented. Finally, practical procedures to mitigate the problem of hydrogen outgassing from lithium hydride are discussed.

  11. Hydridation of Ti-6Al-4V

    International Nuclear Information System (INIS)

    Domizzi, G; Luppo, M.I; Ortiz, M; Vigna, G

    2004-01-01

    The production of Ti pieces or their alloys through powder metallurgy is an economical alternative that replaces the costly methods commonly used. The Ti-6AI-4V alloy is widely used in the aerospace, chemical and medical industries. The use of powder from the alloy instead of using more pure alloyed titanium powders, further simplifies the production process. The presence of V allows the phase β to stabilize at very low temperatures and both alloys alter the Ti-H equilibrium diagram. This work analyzes to what degree these effects influence the obtaining of powders from this alloy from that of hydridation and dehydridation. Although it has slower kinetics, powders can be produced in times similar to those found for grade 2 Ti since the distribution of hydrides in the sample is uniform and the material is fragile enough for concentrations of approximately 0.7 H/Ti (CW)

  12. Rheology of oil sands slurries

    Energy Technology Data Exchange (ETDEWEB)

    Chow, R.; Zhou, J. [Alberta Research Council, Edmonton, AB (Canada). Mineral Oil Sands Unit; Wallace, D. [Dean Wallace Consulting Inc., Beaumont, AB (Canada)

    2006-07-01

    This study focused on integrating rheology and colloid science to improve recovery of bitumen in surface mined oil sands. Factors that influence recovery, such as conditions of particle interaction, solids concentration and shear rate, were reviewed. In an effort to understand the rheological behaviour of clay-in-water suspensions, an elaborate procedure was developed to separate an inter-bedded clay layer from a site at Albian Sands Energy Inc. The variables were water chemistry, solids concentration, and shear rate. The research study was conducted at the Alberta Research Council with the support of the CONRAD Extraction Group. A controlled stress rheometer was used to provide the quantitative evaluations of the clay slurry properties. The research results indicate that the viscoelastic properties of the slurry are highly influenced by the shear history of the slurry, solids content, calcium concentration, and sample aging. Shear thinning behaviour was observed in all slurry samples, but the slurry viscosity increased with test time for a given shear rate. In order to classify the slurries, a method was developed to distinguish the gel strength. The slurries were then classified into 3 distinct patterns, including no gel, weak gel and strong gel. The evolution of the experimental protocols were described along with the current stability maps that correlate the domains of the gel strength according to the solids concentration, calcium ion content, and shear rate. It was concluded that the rheological properties of oil sands slurries influence bitumen recovery in commercial surface-mined oil sands operations. tabs., figs.

  13. Speculations on the existence of hydride ions in proton conducting oxides

    DEFF Research Database (Denmark)

    Poulsen, F.W.

    2001-01-01

    The chemical and physical nature of the hydride ion is briefly treated. Several reactions of the hydride ion in oxides or oxygen atmosphere are given, A number of perovskites and inverse perovskites are listed. which contain the H- ion on the oxygen or B-anion sites in the archetype ABO(3) System...

  14. Zircaloy-4 hydridation

    International Nuclear Information System (INIS)

    Vizcaino, Pablo

    1997-01-01

    The objectives of this work can be summarized as: 1) To reproduce, by heat treatments, matrix microstructures and hydride morphologies similar to those observed in structural components of the CNA-1 and CNE nuclear power plants; 2) To study the evolution of the mechanical properties of the original material with different hydrogen concentrations, such as microhardness, and its capacity to distinguish these materials; 3) To find parameters that allow to estimate the hydrogen content of a material by quantitative metallographic techniques, to be used as complementary in the study of the radioactive materials from reactors

  15. Hydride embrittlement in zircaloy components

    Energy Technology Data Exchange (ETDEWEB)

    Lobo, Raquel M.; Andrade, Arnaldo H.P.; Castagnet, Mariano, E-mail: rmlobo@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Zirconium alloys are used in nuclear reactor cores under high-temperature water environment. During service, hydrogen is generated by corrosion processes, and it is readily absorbed by these materials. When hydrogen concentration exceeds the terminal solid solubility, the excess hydrogen precipitates as zirconium hydride (ZrH{sub 2}) platelets or needles. Zirconium alloys components can fail by hydride cracking if they contain large flaws and are highly stressed. Zirconium alloys are susceptible to a mechanism for crack initiation and propagation termed delayed hydride cracking (DHC). The presence of brittle hydrides, with a K{sub Ic} fracture toughness of only a few MPa{radical}m, results in a severe loss in ductility and toughness when platelet normal is oriented parallel to the applied stress. In plate or tubing, hydrides tend to form perpendicular to the thickness direction due to the texture developed during fabrication. Hydrides in this orientation do not generally cause structural problems because applied stresses in the through-thickness direction are very low. However, the high mobility of hydrogen in a zirconium lattice enables redistribution of hydrides normal to the applied stress direction, which can result in localized embrittlement. When a platelet reaches a critical length it ruptures. If the tensile stress is sufficiently great, crack initiation starts at some of these hydrides. Crack propagation occurs by repeating the same process at the crack tip. Delayed hydride cracking can degrade the structural integrity of zirconium alloys during reactor service. The paper focuses on the fracture mechanics and fractographic aspects of hydride material. (author)

  16. Effect of alkaline slurry on the electric character of the pattern Cu wafer

    International Nuclear Information System (INIS)

    Hu Yi; Liu Yuling; Liu Xiaoyan; He Yangang; Wang Liran; Zhang Baoguo

    2011-01-01

    For process integration considerations, we will investigate the impact of chemical mechanical polishing (CMP) on the electrical characteristics of the pattern Cu wafer. In this paper, we investigate the impacts of the CMP process with two kinds of slurry, one of which is acid slurry of SVTC and the other is FA/O alkaline slurry purchased from Tianjin Jingling Microelectronic Material Limited. Three aspects were investigated: resistance, capacitance and leakage current. The result shows that after polishing by the slurry of FA/O, the resistance is lower than the SVTC. After polishing by the acid slurry and FA/O alkaline slurry, the difference in capacitance is not very large. The values are 0.1 nF and 0.12 nF, respectively. The leakage current of the film polished by the slurry of FA/O is 0.01 nA, which is lower than the slurry of SVTC. The results show that the slurry of FA/O produced less dishing and oxide loss than the slurry of SVTC. (semiconductor technology)

  17. Effect of lapping slurry on critical cutting depth of spinel

    International Nuclear Information System (INIS)

    Wang, Zhan-kui; Wang, Zhuan-kui; Zhu, Yong-wei; Su, Jian-xiu

    2015-01-01

    Highlights: • Measured spinel wafers’ hardness and crack length in different slurries. • Evaluated the softened layer thickness in different slurries. • Discussed the effect of slurries on critical cutting depth of spinel. - Abstract: The critical cutting depth for lapping process is very important because it influences the mode of material removal. In this paper, a serial of microscopic indentation experiments were carried out for measuring spinel wafers’ hardness and crack length in different lapping slurries. Their critical cutting depth and fracture toughness were calculated. X-ray photoelectron spectroscopy (XPS) was also employed to study the surface chemical composition and softened layer thickness of wafers in different slurries. Experimental results indicate that the softened layers of spinel wafers are formed due to the corrosion of lapping slurries, which leads to a lower hardness and a larger fracture toughness of samples, and increases the critical cutting depth. Among them, the critical cutting depth in ethylene glycol solution is the largest and up to 21.8 nm. The increase of critical cutting depth is helpful to modify the surface quality of the work-piece being lapped via ductile removal mode instead of brittle fracture mode

  18. Apparatus for chemical synthesis

    Science.gov (United States)

    Kong, Peter C [Idaho Falls, ID; Herring, J Stephen [Idaho Falls, ID; Grandy, Jon D [Idaho Falls, ID

    2011-05-10

    A method and apparatus for forming a chemical hydride is described and which includes a pseudo-plasma-electrolysis reactor which is operable to receive a solution capable of forming a chemical hydride and which further includes a cathode and a movable anode, and wherein the anode is moved into and out of fluidic, ohmic electrical contact with the solution capable of forming a chemical hydride and which further, when energized produces an oxygen plasma which facilitates the formation of a chemical hydride in the solution.

  19. Slurry pipeline technology: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, Jay P. [Pipeline Systems Incorporated (PSI), Belo Horizonte, MG (Brazil); Lima, Rafael; Pinto, Daniel; Vidal, Alisson [Ausenco do Brasil Engenharia Ltda., Nova Lima, MG (Brazil). PSI Div.

    2009-12-19

    Slurry pipelines represent an economical and environmentally friendly transportation means for many solid materials. This paper provides an over-view of the technology, its evolution and current Brazilian activity. Mineral resources are increasingly moving farther away from ports, processing plants and end use points, and slurry pipelines are an important mode of solids transport. Application guidelines are discussed. State-of-the-Art technical solutions such as pipeline system simulation, pipe materials, pumps, valves, automation, telecommunications, and construction techniques that have made the technology successful are presented. A discussion of where long distant slurry pipelines fit in a picture that also includes thickened and paste materials pipe lining is included. (author)

  20. Slurry flow principles and practice

    CERN Document Server

    Shook, C A; Brenner, Howard

    2015-01-01

    Slurry Flow: Principles and Practice describes the basic concepts and methods for understanding and designing slurry flow systems, in-plan installations, and long-distance transportation systems. The goal of this book is to enable the design or plant engineer to derive the maximum benefit from a limited amount of test data and to generalize operating experience to new situations. Design procedures are described in detail and are accompanied by illustrative examples needed by engineers with little or no previous experience in slurry transport.The technical literature in this field is extensive:

  1. Anodematerials for Metal Hydride Batteries

    DEFF Research Database (Denmark)

    Jensen, Jens Oluf

    1997-01-01

    This report describes the work on development of hydride forming alloys for use as electrode materials in metal hydride batteries. The work has primarily been concentrated on calcium based alloys derived from the compound CaNi5. This compound has a higher capacity compared with alloys used in today......’s hydride batteries, but a much poorer stability towards repeated charge/discharge cycling. The aim was to see if the cycleability of CaNi5 could be enhanced enough by modifications to make the compound a suitable electrode material. An alloying method based on mechanical alloying in a planetary ball mill...

  2. Metal Hydride Compression

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Terry A. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Bowman, Robert [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Smith, Barton [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Anovitz, Lawrence [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jensen, Craig [Hawaii Hydrogen Carriers LLC, Honolulu, HI (United States)

    2017-07-01

    Conventional hydrogen compressors often contribute over half of the cost of hydrogen stations, have poor reliability, and have insufficient flow rates for a mature FCEV market. Fatigue associated with their moving parts including cracking of diaphragms and failure of seal leads to failure in conventional compressors, which is exacerbated by the repeated starts and stops expected at fueling stations. Furthermore, the conventional lubrication of these compressors with oil is generally unacceptable at fueling stations due to potential fuel contamination. Metal hydride (MH) technology offers a very good alternative to both conventional (mechanical) and newly developed (electrochemical, ionic liquid pistons) methods of hydrogen compression. Advantages of MH compression include simplicity in design and operation, absence of moving parts, compactness, safety and reliability, and the possibility to utilize waste industrial heat to power the compressor. Beyond conventional H2 supplies of pipelines or tanker trucks, another attractive scenario is the on-site generating, pressuring and delivering pure H2 at pressure (≥ 875 bar) for refueling vehicles at electrolysis, wind, or solar generating production facilities in distributed locations that are too remote or widely distributed for cost effective bulk transport. MH hydrogen compression utilizes a reversible heat-driven interaction of a hydride-forming metal alloy with hydrogen gas to form the MH phase and is a promising process for hydrogen energy applications [1,2]. To deliver hydrogen continuously, each stage of the compressor must consist of multiple MH beds with synchronized hydrogenation & dehydrogenation cycles. Multistage pressurization allows achievement of greater compression ratios using reduced temperature swings compared to single stage compressors. The objectives of this project are to investigate and demonstrate on a laboratory scale a two-stage MH hydrogen (H2) gas compressor with a

  3. Erbium hydride decomposition kinetics.

    Energy Technology Data Exchange (ETDEWEB)

    Ferrizz, Robert Matthew

    2006-11-01

    Thermal desorption spectroscopy (TDS) is used to study the decomposition kinetics of erbium hydride thin films. The TDS results presented in this report are analyzed quantitatively using Redhead's method to yield kinetic parameters (E{sub A} {approx} 54.2 kcal/mol), which are then utilized to predict hydrogen outgassing in vacuum for a variety of thermal treatments. Interestingly, it was found that the activation energy for desorption can vary by more than 7 kcal/mol (0.30 eV) for seemingly similar samples. In addition, small amounts of less-stable hydrogen were observed for all erbium dihydride films. A detailed explanation of several approaches for analyzing thermal desorption spectra to obtain kinetic information is included as an appendix.

  4. Medical ice slurry production device

    Science.gov (United States)

    Kasza, Kenneth E [Palos Park, IL; Oras, John [Des Plaines, IL; Son, HyunJin [Naperville, IL

    2008-06-24

    The present invention relates to an apparatus for producing sterile ice slurries for medical cooling applications. The apparatus is capable of producing highly loaded slurries suitable for delivery to targeted internal organs of a patient, such as the brain, heart, lungs, stomach, kidneys, pancreas, and others, through medical size diameter tubing. The ice slurry production apparatus includes a slurry production reservoir adapted to contain a volume of a saline solution. A flexible membrane crystallization surface is provided within the slurry production reservoir. The crystallization surface is chilled to a temperature below a freezing point of the saline solution within the reservoir such that ice particles form on the crystallization surface. A deflector in the form of a reciprocating member is provided for periodically distorting the crystallization surface and dislodging the ice particles which form on the crystallization surface. Using reservoir mixing the slurry is conditioned for easy pumping directly out of the production reservoir via medical tubing or delivery through other means such as squeeze bottles, squeeze bags, hypodermic syringes, manual hand delivery, and the like.

  5. Comparative testing of slurry monitors

    International Nuclear Information System (INIS)

    Hylton, T.D.; Bayne, C.K.; Anderson, M.S.; Van Essen, D.C.

    1998-05-01

    The US Department of Energy (DOE) has millions of gallons of radioactive liquid and sludge wastes that must be retrieved from underground storage tanks, transferred to treatment facilities, and processed to a final waste form. The wastes will be removed from the current storage tanks by mobilizing the sludge wastes and mixing them with the liquid wastes to create slurries. Each slurry would then be transferred by pipeline to the desired destination. To reduce the risk of plugging a pipeline, the transport properties (e.g., density, suspended solids concentration, viscosity, particle size range) of the slurry should be determined to be within acceptable limits prior to transfer. These properties should also be monitored and controlled within specified limits while the slurry transfer is in progress. The DOE issued a call for proposals for developing on-line instrumentation to measure the transport properties of slurries. In response to the call for proposals, several researchers submitted proposals and were funded to develop slurry monitoring instruments. These newly developed DOE instruments are currently in the prototype stage. Before the instruments were installed in a radioactive application, the DOE wanted to evaluate them under nonradioactive conditions to determine if they were accurate, reliable, and dependable. The goal of this project was to test the performance of the newly developed DOE instruments along with several commercially available instruments. The baseline method for comparison utilized the results from grab-sample analyses

  6. Rheology of tetraphenylborate precipitate slurry

    International Nuclear Information System (INIS)

    Goren, I.D.; Martin, H.D.; McLain, M.A.

    1985-01-01

    The rheological properties of tetraphenylborate precipitate slurry were determined. This nonradioactive slurry simulates the radioactive tetraphenylborate precipitate generated at the Savannah River Plant by the In-Tank Precipitation Process. The data obtained in this study was applied in the design of slurry pumps, transfer pumps, transfer lines, and vessel agitation for the Defense Waste Processing Facility and other High Level Waste treatment projects. The precipitate slurry behaves as a Bingham plastic. The yield stress is directly proportional to the concentration of insoluble solids over the range of concentrations studied. The consistency is also a linear function of insoluble solids over the same concentration range. Neither the yield stress nor the consistency was observed to be affected by the presence of the soluble solids. Temperature effects on flow properties of the slurry were also examined: the yield stress is inversely proportional to temperature, but the consistency of the slurry is independent of temperature. No significant time-dependent effects were found. 4 refs., 4 figs., 3 tabs

  7. Solubility of hydrogen isotopes in stressed hydride-forming metals

    International Nuclear Information System (INIS)

    Coleman, C.E.; Ambler, J.F.R.

    1983-01-01

    Components made from hydride-forming metals can be brittle when particles of hydride are present. The solid solubility limit of hydrogen in these metals needs to be known so that fracture resistance can be properly assessed. Stress affects the solubility of hydrogen in metals. As hydrogen dissolves the metal volume increases, an applied hydrostatic tensile stress supplies work to increase the solubility. Precipitation of hydrides increases the volume further. A hydrostatic tensile stress promotes the formation of hydrides and tends to reduce the terminal solubility. For materials containing hydrogen in solution in equilibrium with hydrides, the effect of stress on the terminal solubility is given. Hydrogen migrates up tensile stress gradients because of the effect of stress on the solubility and solubility limit. Consequently, hydrogen concentrates at flaws. When hydrides are present in the metal matrix, those remote from the flaw tip will preferentially dissolve in favor of those precipitated at the flaw. If the stress is large enough, at some critical condition the hydrides at the flaw will crack. This is delayed hydrogen cracking. Notched and fatigue-cracked cantilever beam specimens (6) (38 x 4 x 3 mm) were machined from the circumferential direction of several cold-worked Zr-2.5 at. % Nb pressure tubes. The chemical compositions had the ranges (in atomic %) Nb - 2.5 to 2.7; O - 0.58 to 0.71; H - 0.018 to 0.18. The effect of test temperature is for a specimen containing 0.13 at. % protium and 0.29 at .% deuterium. Between 505 K and 530 K was less than 1 hr, between 530 K and 537 K it increased to 25.8 h, while at 538 K no cracking was observed up to the 54 h

  8. Microcapsulated rare earth - nickel hydride-forming materials

    International Nuclear Information System (INIS)

    Ishikawa, H.; Oguro, K.; Kato, A.; Suzuki, H.; Ishii, E.

    1985-01-01

    Fine particles of hydride-forming alloys such as LaNi/sub 5/ and MmNi/sub 4.5/Mn/sub 0.5/ (MM : mischmetal) were coated with metallic copper thin layer by chemical plating method. Hydrogen storage capacities of alloys were not appreciably affected by the plating treatment. The capsulated alloy powders were easily pressed into pellets. The pellets obtained had high thermal conductivity and porosity enough to permeate hydrogen, leading to fast reaction kinetics. These were able to withstand more than 5,000 repeated hydriding-dehydriding cycles without disintegrating

  9. A simple biofilter for treatment of pig slurry in Malaysia.

    Science.gov (United States)

    Sommer, S G; Mathanpaal, G; Dass, G T

    2005-03-01

    On commercial pig production farms in South East (SE) Asia, the liquid effluent is often discharged into rivers. The discharge is a hazard to the environment and to the health of people using water from the river either for consumption or for irrigation. Therefore, a simple percolation biofilter for treatment of the liquid effluent was developed. Pig slurry was treated in test-biofilters packed with different biomass for the purpose of selecting the most efficient material, thereafter the efficiency of the biofilter was examined at farm scale with demo biofilters using the most efficient material. The effect of using "Effective Microorganisms" (EM) added to slurry that was treated with biofilter material mixed with Glenor KR+ was examined. Slurry treatment in the test-biofilters indicated that rice straw was better than coconut husks, wood shavings, rattan strips and oil palm fronds in reducing BOD. Addition of EM and Glenor KR+ to slurry and biofilter material, respectively, had no effect on the temperature of the biofilter material or on the concentrations of organic and inorganic components of the treated slurry. The BOD of slurry treated in test biofilters is reduced to between 80 and 637 mg O2 I(-1) and in the demo biofilter to between 3094 and 3376 mg O2 l(-1). The concentration of BOD in the effluent is related to the BOD in the slurry being treated and the BOD concentration in slurry treated in test biofilters was lower than BOD of slurry treated in demo biofilters. The demo biofilter can reduce BOD to between 52 an 56% of the original value, and TSS, COD (chemical oxygen demand) and ammonium (NH4+) to 41-55% of the original slurry. The treated effluent could not meet the standards for discharge to rivers. The composted biofilter material has a high content of nitrogen and phosphorus; consequently, the fertilizer value of the compost is high. The investments costs were 123 US dollar per SPP which has to be reduced if this method should be a treatment option

  10. Evaluation of the transport and resuspension of a simulated nuclear waste slurry: Nuclear Waste Treatment Program

    International Nuclear Information System (INIS)

    Carleson, T.E.; Drown, D.C.; Hart, R.E.; Peterson, M.E.

    1987-09-01

    The Department of Chemical Engineering at the University of Idaho conducted research on the transport and resuspension of a simulated high-level nuclear waste slurry. In the United States, the reference process for treating both defense and civilian HLLW is vitrification using the liquid-fed ceramic melter process. The non-Newtonian behavior of the slurry complicates the evaluation of the transport and resuspension characteristics of the slurry. The resuspension of a simulated (nonradioactive) melter feed slurry was evaluated using a slurry designated as WV-205. The simulated slurry was developed for the West Valley Demonstration Project and was used during a pilot-scale ceramic melter (PSCM) experiment conducted at PNL in July 1985 (PSCM-21). This study involved determining the transport characteristics of a fully suspended slurry and the resuspension characteristics of settled solids in a pilot-scale pipe loop. The goal was to predict the transport and resuspension of a full-scale system based on rheological data for a specific slurry. The rheological behavior of the slurry was evaluated using a concentric cylinder rotational viscometer, a capillary tube viscometer, and the pilot-scale pipe loop. The results obtained from the three approaches were compared. 40 refs., 74 figs., 15 tabs

  11. Mineralenconcentraten uit dierlijke mest = Mineral concentrates from animal slurry

    NARCIS (Netherlands)

    Hoeksma, P.; Buisonjé, de F.E.

    2012-01-01

    In 2011 6 pilot production plants of mineral concentrates from animal manure were monitored, with the aim of gathering additional data on the chemical composition of the raw slurry and the end products. Beside that a literature review was executed to reveal the biological degradability of

  12. Hydriding failure in water reactor fuel elements

    International Nuclear Information System (INIS)

    Sah, D.N.; Ramadasan, E.; Unnikrishnan, K.

    1980-01-01

    Hydriding of the zircaloy cladding has been one of the important causes of failure in water reactor fuel elements. This report reviews the causes, the mechanisms and the methods for prevention of hydriding failure in zircaloy clad water reactor fuel elements. The different types of hydriding of zircaloy cladding have been classified. Various factors influencing zircaloy hydriding from internal and external sources in an operating fuel element have been brought out. The findings of post-irradiation examination of fuel elements from Indian reactors, with respect to clad hydriding and features of hydriding failure are included. (author)

  13. Valence properties of tellurium in different chemical systems and its determination in refractory environmental samples using hydride generation – Atomic fluorescence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yu-Wei; Alzahrani, Ali [Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6 (Canada); Deng, Tian-Long [College of Marine Science and Engineering, Tianjin University of Science and Technology, Tianjin (China); Belzile, Nelson, E-mail: nbelzile@laurentian.ca [Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6 (Canada); Cooperative Freshwater Ecology Unit, Laurentian University, Sudbury, Ontario P3E 2C6 (Canada)

    2016-01-28

    Using HG – AFS as a powerful tool to study valence transformations of Te, we found that, in presence of HCl and at high temperature, Te can form volatile species and be lost during sample digestion and pre-reduction steps. It was also noticed that the chemical valences of Te can be modified under different chemical and digestion conditions and even by samples themselves with certain matrices. KBr can reduce Te(VI) to Te(IV) in 3.0 M HCl at 100 °C, but when HNO{sub 3} was >5% (v/v) in solution, Br{sub 2} was formed and caused serious interference to Te measurements. HCl alone can also pre-reduce Te(VI) to Te(IV), only when its concentration was ≥6.0 M (100 °C for 15min). Among 10 studied chemical elements, only Cu{sup 2+} caused severe interference. Thiourea is an effective masking agent only when Cu{sup 2+} concentration is equal or lower than 10 mg/L. Chemical reagents, chemical composition of sample, as well as the modes of digestion can greatly affect Te valences, reagent blanks and analytical precisions. A protocol of 2–step–digestion followed by an elimination of HF is proposed to minimize reagent blank and increase the signal/noise ratios. It is important to perform a preliminary test to confirm whether a pre-reduction step is necessary; this is especially true for samples with complex matrices such as those with high sulfide content. The analytical detection limits of this method in a pure solution and a solid sample were 100 ng/L and 0.10 ± 0.02 μg/g, respectively. - Highlights: • HG–AFS is a powerful tool in studies of chemical valences and forms of Te in different conditions. • Te can be lost in form of volatile species in presence of HCl at high temperature. • Metal ions can be classified into 3 categories of interference; thiourea can effectively mask Cu{sup 2+}. • A 2-step digestion allows to eliminate HF, reduce background and improve analytical precision. • Matrix of sample can strongly influence Te chemical valence

  14. Results for the First, Second, and Third Quarter Calendar Year 2015 Tank 50H WAC slurry samples chemical and radionuclide contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-02-18

    This report details the chemical and radionuclide contaminant results for the characterization of the Calendar Year (CY) 2015 First, Second, and Third Quarter sampling of Tank 50H for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time. Information from this characterization will be used by Defense Waste Processing Facility (DWPF) & Saltstone Facility Engineering (D&S-FE) to support the transfer of low-level aqueous waste from Tank 50H to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50H Waste Characterization System. Previous memoranda documenting the WAC analyses results have been issued for these three samples.

  15. Technical report on treatment of radioactive slurry liquid waste

    International Nuclear Information System (INIS)

    Jeong, Gyeong Hwan; Jo, Eun Sung; Park, Seung Kook; Jung, Ki Jung

    1999-06-01

    By literature survey, this report deals with the technology on typical pre-treatment and filtration of radioactive slurry liquid waste, produced during the operation of TRIGA Mark-II, III research reactor, and produced during the decommission/decontamination of TRIGA Mark-II, III research reactor. It is reviewed pre-treatment procedure, both physical and chemical that optimise the dewatering characteristics, and also surveyed types of dewatering devices based on centrifuges, vacuum and pressure filters with particular reference to various combined field approaches using two or more complementary driving forces to achieve better performance. Dewatering operations and devises on filtration of radioactive slurry liquid waste are also analysed. (author)

  16. Single-Site Tetracoordinated Aluminum Hydride Supported on Mesoporous Silica. From Dream to Reality!

    KAUST Repository

    Werghi, Baraa

    2016-09-26

    The reaction of mesoporous silica (SBA15) dehydroxylated at 700 °C with diisobutylaluminum hydride, i-Bu2AlH, gives after thermal treatment a single-site tetrahedral aluminum hydride with high selectivity. The starting aluminum isobutyl and the final aluminum hydride have been fully characterized by FT-IR, advanced SS NMR spectroscopy (1H, 13C, multiple quanta (MQ) 2D 1H-1H, and 27Al), and elemental analysis, while DFT calculations provide a rationalization of the occurring reactivity. Trimeric i-Bu2AlH reacts selectively with surface silanols without affecting the siloxane bridges. Its analogous hydride catalyzes ethylene polymerization. Indeed, catalytic tests show that this single aluminum hydride site is active in the production of a high-density polyethylene (HDPE). © 2016 American Chemical Society.

  17. Getting metal-hydrides to do what you want them to

    International Nuclear Information System (INIS)

    Gruen, D.M.

    1981-01-01

    With the discovery of AB 5 compounds, intermetallic hydrides with unusual properties began to be developed (H dissociation pressures of one to several atmospheres, extremely rapid and reversible adsorption/desorption very large amounts of H adsorbed). This paper reviews the factors that must be controlled in order to modify these hydrides to make them useful. The system LaNi 5 + H 2 is used as example. Use of AB 5 hydrides to construct a chemical heat pumps is discussed. Results of a systematic study substituting Al for Ni are reported; the HYCSOS pump is described briefly. Use of hydrides as hydrogen getters (substituted ZrV 2 ) is also discussed. Finally, possible developments in intermetallic hydride research in the 1980's and the hydrogen economy are discussed. 10 figures

  18. Single-Site Tetracoordinated Aluminum Hydride Supported on Mesoporous Silica. From Dream to Reality!

    KAUST Repository

    Werghi, Baraa; Bendjeriou-Sedjerari, Anissa; Jedidi, Abdesslem; Abou-Hamad, Edy; Cavallo, Luigi; Basset, Jean-Marie

    2016-01-01

    The reaction of mesoporous silica (SBA15) dehydroxylated at 700 °C with diisobutylaluminum hydride, i-Bu2AlH, gives after thermal treatment a single-site tetrahedral aluminum hydride with high selectivity. The starting aluminum isobutyl and the final aluminum hydride have been fully characterized by FT-IR, advanced SS NMR spectroscopy (1H, 13C, multiple quanta (MQ) 2D 1H-1H, and 27Al), and elemental analysis, while DFT calculations provide a rationalization of the occurring reactivity. Trimeric i-Bu2AlH reacts selectively with surface silanols without affecting the siloxane bridges. Its analogous hydride catalyzes ethylene polymerization. Indeed, catalytic tests show that this single aluminum hydride site is active in the production of a high-density polyethylene (HDPE). © 2016 American Chemical Society.

  19. Simultaneous determination of hydride and non-hydride forming elements by inductively coupled plasma optical emission spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Benzo, Z. [Instituto Venezolano de Investigaciones Cientificas, IVIC, Altos de Pipe, Caracas (Venezuela, Bolivarian Republic of); Matos-Reyes, M.N.; Cervera, M.L.; Guardia, M. de la, E-mail: m.luisa.cervera@uv.es [Department of Analytical Chemistry, University of Valencia, Valencia (Spain)

    2011-09-15

    The operating characteristics of a dual nebulization system were studied including instrumental and chemical conditions for the hydride generation and analytical figures of merit for both, hydride and non hydride forming elements. Analytical performance of the nebulization system was characterized by detection limits from 0.002 to 0.0026 {mu}g mL{sup -1} for the hydride forming elements and between 0.0034 and 0.0121 {mu}g mL{sup -1} for the non-hydride forming elements, relative standard deviation for 10 replicate measurements at 0.25 mg L{sup -1} level and recovery percentages between 97 and 103%. The feasibility of the system was demonstrated in the simultaneous determination of Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Zn, As, Bi, Sb, Se, and Te in the NIST 1549 (non-fat milk powder), NIST 1570a (spinach leaves), DORM-2 (dogfish muscle) and TORT-2 (lobster hepatopancreas) certified samples for trace elements. Results found were in good agreement with the certified ones. (author)

  20. Synthesis and characterization of cement slurries additives with epoxy resins - kinetics, thermodynamic and calorimetric analysis

    International Nuclear Information System (INIS)

    Tavares, A.M.G.; Andrade Junior, M.A.S.; Cestari, A.R.; Vieira, E.F.S.

    2010-01-01

    Cement has been used in the world, presenting a wide versatility. However, due to its chemical nature, it is subject to several types of chemical damages, especially for agents of acidic nature. With the purpose of increase its life-time, new cement slurries have been modified with the addition of specific additives. The objective of this work is to modify cement slurries with epoxy resins, which promote higher resistance of those materials in relation to acid attacks. Three cement slurries were synthesized with epoxy resins and a standard slurries, which was composed by cement and water. After 30 days of hydration, the samples were characterized by XDR, FTIR and thermal analysis (TG and DSC). The hydration processes of the cement slurries were studied by heat-conduction microcalorimetry. A kinetic study of HCl interaction with the new slurries were performed by the batch methodology at 25, 35, 45 e 55 deg C. It was verified that the addition of the polymers delayed the processes of hydration of the slurries, decreasing the flow of heat released as a function of the amount of added resin and, increased the resistance of those slurries to the acid attack. (author)

  1. Microalgal cultivation with biogas slurry for biofuel production.

    Science.gov (United States)

    Zhu, Liandong; Yan, Cheng; Li, Zhaohua

    2016-11-01

    Microalgal growth requires a substantial amount of chemical fertilizers. An alternative to the utilization of fertilizer is to apply biogas slurry produced through anaerobic digestion to cultivate microalgae for the production of biofuels. Plenty of studies have suggested that anaerobic digestate containing high nutrient contents is a potentially feasible nutrient source to culture microalgae. However, current literature indicates a lack of review available regarding microalgal cultivation with biogas slurry for the production of biofuels. To help fill this gap, this review highlights the integration of digestate nutrient management with microalgal production. It first unveils the current status of microalgal production, providing basic background to the topic. Subsequently, microalgal cultivation technologies using biogas slurry are discussed in detail. A scale-up scheme for simultaneous biogas upgrade and digestate application through microalgal cultivation is then proposed. Afterwards, several uncertainties that might affect this practice are explored. Finally, concluding remarks are put forward. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. A Fast and Efficient Dehydration Process for Waste Drilling Slurry

    Directory of Open Access Journals (Sweden)

    Zheng Guo

    2017-01-01

    Full Text Available In this article, slurry system was converted to colloid from fluid with the colloidization of high polymer coagulants with high viscosity. The solid-liquid separation of the waste slurry was realized by the process of chemical colloidal gel breaking, coagulation function, acidification gelout. In addition, the surface morphology of slurry cake was investigated by using Field emission scanning electron microscope (FE-SEM. The results indicate that mud separation effect is decides on the type of flocculants, gel breaker. The solid content of mud cake increases from 40.5% to 77.5% when A-PA and H20 are employed as the flocculants, gelout, with the dosage of zero point four grams and zero point five grams.

  3. Mechanical properties and fracture of titanium hydrides

    International Nuclear Information System (INIS)

    Koketsu, Hideyuki; Taniyama, Yoshihiro; Yonezu, Akio; Cho, Hideo; Ogawa, Takeshi; Takemoto, Mikio; Nakayama, Gen

    2006-01-01

    Titanium hydrides tend to suffer fracture when their thicknesses reach a critical thickness. Morphology and mechanical property of the hydrides are, however, not well known. The study aims to reveal the hydride morphology and fracture types of the hydrides. Chevron shaped plate hydrides were found to be produced on the surface of pure titanium (Grade 1) and Grade 7 titanium absorbing hydrogen. There were tree types of fracture of the hydrides, i.e., crack in hydride layer, exfoliation of the layer and shear-type fracture of the hydride plates, during the growth of the hydrides and deformation. We next estimated the true stress-strain curves of the hydrides on Grade 1 and 7 titanium using the dual Vickers indentation method, and the critical strain causing the Mode-I fine crack by indentation. Fracture strength and strain of the hydrides in Grade 1 titanium were estimated as 566 MPa and 4.5%, respectively. Those of the hydride in Grade 7 titanium were 498 MPa and 16%. Though the fracture strains estimated from the plastic instability of true stress-strain curves were approximately the half of those estimated by finite element method, the titanium hydrides were estimated to possess some extent of toughness or plastic deformation capability. (author)

  4. Ammonia abatement by slurry acidification

    DEFF Research Database (Denmark)

    Petersen, Søren O.; Hutchings, Nicholas John; Hafner, Sasha D.

    2016-01-01

    sections with 30-32 pigs with or without daily adjustment of slurry pH to below 6. Ammonia losses from reference sections with untreated slurry were between 9.5 and 12.4% of N excreted, and from sections with acidified slurry between 3.1 and 6.2%. Acidification reduced total emissions of NH3 by 66 and 71......% in spring and autumn experiments, and by 44% in the summer experiment. Regression models were used to investigate sources and controls of NH3 emissions. There was a strong relationship between NH3 emissions and ventilation rate during spring and autumn, but less so during summer where ventilation rates were...

  5. High-pressure hydriding of Zircaloy

    International Nuclear Information System (INIS)

    Kim, Y.S.

    1996-01-01

    The hydriding characteristics of Zircaloy-2(Zry), sponge zirconium (as a liner on Zry plate), and crystal-bar zirconium exposed to pure H 2 at 0.1 MPa or 7 MPa and 400 C were determined in a thermogravimetric apparatus. The morphology of the hydrided specimens was also examined by optical microscopy. For all specimen types, the rate of hydriding in 7 MPa H 2 was two orders of magnitude greater than in 0.1 MPa H 2 . For Zry, uniform bulk hydriding was revealed by hydride precipitates at room temperature and on one occasion, a sunburst hydride. In addition, all specimen types exhibited a hydride surface layer. In a duplex Zry/sponge-Zr specimen, Zry is more heavily hydrided than the sponge Zr layer. (orig.)

  6. Hydride Olefin complexes of tantalum and niobium

    NARCIS (Netherlands)

    Klazinga, Aan Hendrik

    1979-01-01

    This thesis describes investigations on low-valent tantalum and niobium hydride and alkyl complexes, particularly the dicyclopentadienyl tantalum hydride olefin complexes Cp2Ta(H)L (L=olefin). ... Zie: Summary

  7. Metal hydride compositions and lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Young, Kwo; Nei, Jean

    2018-04-24

    Heterogeneous metal hydride (MH) compositions comprising a main region comprising a first metal hydride and a secondary region comprising one or more additional components selected from the group consisting of second metal hydrides, metals, metal alloys and further metal compounds are suitable as anode materials for lithium ion cells. The first metal hydride is for example MgH.sub.2. Methods for preparing the composition include coating, mechanical grinding, sintering, heat treatment and quenching techniques.

  8. The CO{sub 2} hydrate slurry; Le coulis de glace

    Energy Technology Data Exchange (ETDEWEB)

    Sari, O.; Hu, J.; Eicher, S.; Brun, F. [Institute of Thermal Engineering, University of Applied Sciences of Western Switzerland, Yverdon-les-Bains (Switzerland); Sari, O.; Hu, J. [Clean Cooling Solutions, spin off of University of Applied Sciences of Western Switzerland, Yverdon-les-Bains (Switzerland); Homsy, P. [Nestec Ltd, Vevey (Switzerland); Logel, J.-C. [Axima Refrigeration, Bischheim (France)

    2007-12-15

    A new, very promising refrigerant was developed, which could be used in industrial processes as well as air conditioners: the CO{sub 2} hydrate slurry. Replacing hydrochlorofluorocarbon HCFC refrigerants has a high priority, due to the strong negative environmental impact of these fluids. New refrigerants have to be environment friendly, non-inflammable, cheap and made of natural materials. CO{sub 2} hydrate slurries and/or a mixture of ice slurry and CO{sub 2} hydrate slurry meet these requirements. The University of Applied Sciences of Western Switzerland in Yverdon, together with industrial partners, investigated the properties of such slurries. The slurries were created using the Coldeco process: the refrigerating fluid is directly injected into the liquid brine. The evaporation of the refrigerating fluid cools the liquid down to its freezing point and homogeneously distributed small crystals appear in the liquid. A test rig was built to measure the physical and chemical properties of the slurries obtained in this way. CO{sub 2} hydrate slurries have a higher energy storage capacitance (500 kJ/kg) than ice slurries (333 kJ/kg). The production of CO{sub 2} hydrate slurries in large quantities in a continuous process was demonstrated. The solid particle concentration was 10%, the pressure amounted to 30 bar and the temperature 2 to 4 {sup o}C. Such slurries can be pumped and circulated in pipe networks. Stainless steel is the appropriate material for such networks. However, the main advantage of the new refrigerant will be, according to the authors, a reduced energy consumption compared to traditional refrigerating cycles: the difference between the temperature required by the user and the refrigerant temperature is reduced, thanks to the use of the latent heat in the new process.

  9. Semisolid slurry of 7A04 aluminum alloy prepared by electromagnetic stirring and Sc, Zr additions

    Directory of Open Access Journals (Sweden)

    Jun-wen Zhao

    2017-05-01

    Full Text Available Slurry preparation is one of the most critical steps for semisolid casting, and its primary goal is to prepare slurry with uniformly distributed fine globules. In this work, electromagnetic stirring (EMS and the addition of Sc and Zr elements were used to prepare semisolid slurry of 7A04 aluminum alloy in a large diameter slurry maker. The effects of different treatments on the microstructure, composition and their radial homogeneity were investigated. The results show that, compared to the slurry without any treatment, large volume slurry with finer and more uniform microstructure can be obtained when treated by EMS, Sc, or Zr additions individually. EMS is more competent in the microstructural and chemical homogenization of the slurry while Sc and Zr additions are more excellent in its microstructural refinement. The combined treatment of EMS, Sc and Zr produces premium 7A04 aluminum alloy slurry with uniformly distributed fine α-Al globules and composition. The interaction mechanism between EMS and Sc and Zr additions was also discussed.

  10. Trapping interference effects of arsenic, antimony and bismuth hydrides in collection of selenium hydride within iridium-modified transversally-heated graphite tube atomizer

    Energy Technology Data Exchange (ETDEWEB)

    Furdikova, Zuzana [Department of Environmental Chemistry and Technology, Faculty of Chemistry, Brno University of Technology, Purkynova 118, CZ-61200 Brno (Czech Republic); Institute of Analytical Chemistry of the Academy of Sciences of the Czech Republic v.v.i., Veveri 97, CZ-60200, Brno (Czech Republic); Docekal, Bohumil [Institute of Analytical Chemistry of the Academy of Sciences of the Czech Republic v.v.i., Veveri 97, CZ-60200, Brno (Czech Republic)], E-mail: docekal@iach.cz

    2009-04-15

    Interference effects of co-generated hydrides of arsenic, antimony and bismuth on trapping behavior of selenium hydride (analyte) within an iridium-modified, transversely heated graphite tube atomizer (THGA) were investigated. A twin-channel hydride generation system was used for independent separate generation and introduction of analyte and interferent hydrides, i.e. in a simultaneous and/or sequential analyte-interferent and interferent-analyte mode of operation. The influence of the analyte and modifier mass, interferent amount, trapping temperature and composition of the gaseous phase was studied. A simple approach for the elimination of mutual interference effects by modification of the gaseous phase with oxygen in a substoichiometric ratio to chemically generated hydrogen is proposed and the suppression of these interference effects is demonstrated. A hypothesis on the mechanism of trapping and mutual interference effects is drawn.

  11. Hydrides of Alkaline Earth–Tetrel (AeTt) Zintl Phases: Covalent Tt–H Bonds from Silicon to Tin

    Energy Technology Data Exchange (ETDEWEB)

    Auer, Henry; Guehne, Robin; Bertmer, Marko; Weber, Sebastian; Wenderoth, Patrick; Hansen, Thomas Christian; Haase, Jürgen; Kohlmann, Holger (Leipzig); (Saarland-MED); (ILL)

    2017-01-18

    Zintl phases form hydrides either by incorporating hydride anions (interstitial hydrides) or by covalent bonding of H to the polyanion (polyanionic hydrides), which yields a variety of different compositions and bonding situations. Hydrides (deuterides) of SrGe, BaSi, and BaSn were prepared by hydrogenation (deuteration) of the CrB-type Zintl phases AeTt and characterized by laboratory X-ray, synchrotron, and neutron diffraction, NMR spectroscopy, and quantum-chemical calculations. SrGeD4/3–x and BaSnD4/3–x show condensed boatlike six-membered rings of Tt atoms, formed by joining three of the zigzag chains contained in the Zintl phase. These new polyanionic motifs are terminated by covalently bound H atoms with d(Ge–D) = 1.521(9) Å and d(Sn–D) = 1.858(8) Å. Additional hydride anions are located in Ae4 tetrahedra; thus, the features of both interstitial hydrides and polyanionic hydrides are represented. BaSiD2–x retains the zigzag Si chain as in the parent Zintl phase, but in the hydride (deuteride), it is terminated by H (D) atoms, thus forming a linear (SiD) chain with d(Si–D) = 1.641(5) Å.

  12. Synthesis, properties, and assimilation methods of aluminium hydride

    International Nuclear Information System (INIS)

    Mirsaidov, U.M.

    2013-01-01

    We have discovered a new source of aluminium hydride-conversion of tetrahydrofurane under influence of halogenous alkyls. We have proposed the chlorbenzene method of synthesis of AlH 3 , which excludes adhesion and ensure high quality of the product with respect to its purity, thermal stability, habits of crystals (round shape), and granulometric composition. We determined capability of benzyl chloride to fix AlH 4 -groups by the way of complexes formation. This allows increasing efficient concentration of AlH 3 solutions and their productivity. We have carried out 'direct' crystallization of aluminium hydride in one stage using interaction of binary metal hydride with aluminium chloride in the medium of ether-toluene at 60-100 d ig C a nd using solvent distillation. In the reaction of Li H with AlCl 3 , we achieved output of pure crystal AlH 3 of hexagonal modification, which was close to quantitative. We have discovered the assimilation methods of aluminium hydride in carrying out of solid-phase chemical reactions. (author)

  13. Optical emission spectrometric determination of arsenic and antimony by continuous flow chemical hydride generation and a miniaturized microwave microstrip argon plasma operated inside a capillary channel in a sapphire wafer

    International Nuclear Information System (INIS)

    Pohl, Pawel; Zapata, Israel Jimenez; Bings, Nicolas H.; Voges, Edgar; Broekaert, Jose A.C.

    2007-01-01

    Continuous flow chemical hydride generation coupled directly to a 40 W, atmospheric pressure, 2.45 GHz microwave microstrip Ar plasma operated inside a capillary channel in a sapphire wafer has been optimized for the emission spectrometric determination of As and Sb. The effect of the NaBH 4 concentration, the concentration of HCl, HNO 3 and H 2 SO 4 used for sample acidification, the Ar flow rate, the reagent flow rates, the liquid volume in the separator as well as the presence of interfering metals such as Fe, Cu, Ni, Co, Zn, Cd, Mn, Pb and Cr, was investigated in detail. A considerable influence of Fe(III) (enhancement of up to 50 %) for As(V) and of Fe(III), Cu(II) and Cr(III) (suppression of up to 75%) as well as of Cd(II) and Mn(II) (suppression by up to 25%) for Sb(III) was found to occur, which did not change by more than a factor of 2 in the concentration range of 2-20 μg ml -1 . The microstrip plasma tolerated the introduction of 4.2 ml min -1 of H 2 in the Ar working gas, which corresponded to an H 2 /Ar ratio of 28%. Under these conditions, the excitation temperature as measured with Ar atom lines and the electron number density as determined from the Stark broadening of the H β line was of the order of 5500 K and 1.50 . 10 14 cm -3 , respectively. Detection limits (3σ) of 18 ng ml -1 for As and 31 ng ml -1 for Sb were found and the calibration curves were linear over 2 orders of magnitude. With the procedure developed As and Sb could be determined at the 45 and 6.4 μg ml -1 level in a galvanic bath solution containing 2.5% of NiSO 4 . Additionally, As was determined in a coal fly ash reference material (NIST SRM 1633a) with a certified concentration of As of 145 ± 15 μg g -1 and a value of 144 ± 4 μg g -1 was found

  14. Fluidization mechanisms in slurry flow

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, C. S.

    1989-01-01

    There are two mechanisms by which heavy settling particles may be suspended in a horizontal slurry flow: (1) by particle-particle interactions (e.g. Bagnold dispersive stresses) and (2) by particle-fluid interactions (e.g. entrainment of the particles by turbulent eddies.) The purpose of this investigation is to determine to what extent each fluidization mechanism is active and the effect of the fluidization mechanism on the global properties of the slurry. The technique employs the understanding that the particles entrained in the turbulence of the fluid will appear as an increased hydrostatic head across the channel. This may be directly measured and can be related to the fraction of the mass of particles that are supported by fluid-particle forces. (The rest must therefore be supported by particle-particle forces.) 17 refs., 26 figs.

  15. Agronomic valuing of slurry for management in common

    International Nuclear Information System (INIS)

    Gomez, M.; Estevez, M. D.; Faz, A.; Olivares, A. B.; Climent, V.

    2009-01-01

    Due to the intensification of livestock production and the concentration of holdings in specific areas, has disrupted the balance between production and utilization of swine waste in agriculture. given the volume of slurry generated in Murcia, and the total cultivable area and considering the legislation, RD 261/1996, which allows a maximum application of 170 kg N/ha year in areas designated as vulnerable, it is estimated that to implement the slurry generated in the region in a year, would require only half the arable land devoted to irrigation. In this way, this study has included detailed monitoring of the effect of the application of ping slurry at a concentration recommended on the properties and chemical, physical and biological properties of soil, water and plant to determine the influence of slurry on the reserve of organic matter in each of these crops, as well as contaminated soils, through the creation of a pilot system for managing livestock waste in accordance with preventive measures that allow for their optimal use, without risk of contamination for the system water-soil-plant. (Author 6 refs.

  16. Coal slurries: An environmental bonus?

    International Nuclear Information System (INIS)

    Basta, N.; Moore, S.; Ondrey, G.

    1994-01-01

    Developers and promoters of coal-water slurries and similar CWF (coal-water fuel) technologies have had a hard time winning converts since they unveiled their first commercial processes in the 1970s. The economic appeal of such processes, marginal at best, varies with the price of oil. Nevertheless, the technology is percolating, as geopolitics and environmental pressures drive new processes. Such fuels are becoming increasingly important to coal-rich, oil-poor nations such as China, as they attempt to build an onshore fuel supply. Meanwhile, improvements are changing the way coal-fired processes are viewed. Where air pollution regulations once discouraged the use of coal fuels, new coal processes have been developed that cut nitrous oxides (NOx) emissions and provide a use for coal fines, previously viewed as waste. The latest developments in the field were all on display at the 19th International Technical Conference on Coal Utilization and Fuel Systems, held in Clearwater, Fla., on March 21--24. At this annual meeting, sponsored by the Coal and Slurry Technology Association, (Washington, D.C.) and the Pittsburgh Energy Technology Center of the US Dept. of Energy (PETC), some 200 visitors from around the work gathered to discuss the latest developments in coal slurry utilization--new and improved processes, and onstream plants. This paper presents highlights from the conference

  17. Evaluation of V, Ir, Ru, V-Ir, V-Ru, and W-V as permanent chemical modifiers for the determination of cadmium, lead, and zinc in botanic and biological slurries by electrothermal atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Acar, Orhan

    2005-01-01

    Permanent modifiers (V, Ir, Ru, V-Ir, V-Ru, and W-V) thermally coated on to platforms of pyrolytic graphite tubes were employed for the determination of Cd, Pb, and Zn in botanic and biological slurries by electrothermal atomic absorption spectrometry (ETAAS). Conventional Pd + Mg(NO 3 ) 2 modifier mixture was also used for the determination of analytes in slurries and digested samples. Optimum masses and mass ratios of permanent modifiers for Cd, Pb, and Zn in slurry sample solutions were investigated. The 280 μg of V, 280 μg of V + 200 μg of Ir, 280 μg of V + 200 μg of Ru or 240 μg of W + 280 μg of V in 0.2% (v/v) Triton X-100 plus 0.5% (v/v) HNO 3 mixture was found as efficient as 5 μg of Pd + 3 μg of Mg(NO 3 ) 2 modifier mixture for obtaining thermal stabilization, and for obtaining best recoveries. Optimization conditions of analytes, such as pyrolysis and atomization temperature, characteristic masses and detection limits, and atomization and background peak profiles were studied with permanent and 5 μg of Pd + 3 μg of Mg(NO 3 ) 2 conventional modifiers and compared with each other. The permanent V-Ir, V-Ru, and W-V modifiers remained stable for approximately 250-300 firings when 20 μl of slurries and digested samples were delivered into the atomizer. In addition, the mixed permanent modifiers increase the tube lifetime by 50-95% when compared with untreated platforms. The characteristic masses and detection limits of analytes (dilution factor of 125 ml g -1 ) obtained with V-Ir based on integrated absorbance as example for 0.8% (m/v) slurries were 1.0 pg and 3 ng g -1 for Cd, 18 pg and 17 ng g -1 for Pb, and 0.7 pg and 4 ng g -1 for Zn, respectively. The results of analytes obtained by employing V-Ir, V-Ru, and W-V permanent modifier mixtures in botanic and biological certified and standard reference materials were in agreement with the certified values of reference materials

  18. Tritium processing using metal hydrides

    International Nuclear Information System (INIS)

    Mallett, M.W.

    1986-01-01

    E.I. duPont de Nemours and Company is commissioned by the US Department of Energy to operate the Savannah River Plant and Laboratory. The primary purpose of the plant is to produce radioactive materials for national defense. In keeping with current technology, new processes for the production of tritium are being developed. Three main objectives of this new technology are to ease the processing of, ease the storage of, and to reduce the operating costs of the tritium production facility. Research has indicated that the use of metal hydrides offers a viable solution towards satisfying these objectives. The Hydrogen and Fuels Technology Division has the responsibility to conduct research in support of the tritium production process. Metal hydride technology and its use in the storage and transportation of hydrogen will be reviewed

  19. Rechargeable metal hydrides for spacecraft application

    Science.gov (United States)

    Perry, J. L.

    1988-01-01

    Storing hydrogen on board the Space Station presents both safety and logistics problems. Conventional storage using pressurized bottles requires large masses, pressures, and volumes to handle the hydrogen to be used in experiments in the U.S. Laboratory Module and residual hydrogen generated by the ECLSS. Rechargeable metal hydrides may be competitive with conventional storage techniques. The basic theory of hydride behavior is presented and the engineering properties of LaNi5 are discussed to gain a clear understanding of the potential of metal hydrides for handling spacecraft hydrogen resources. Applications to Space Station and the safety of metal hydrides are presented and compared to conventional hydride storage. This comparison indicates that metal hydrides may be safer and require lower pressures, less volume, and less mass to store an equivalent mass of hydrogen.

  20. The stability of a novel weakly alkaline slurry of copper interconnection CMPfor GLSI

    Science.gov (United States)

    Yao, Caihong; Wang, Chenwei; Niu, Xinhuan; Wang, Yan; Tian, Shengjun; Jiang, Zichao; Liu, Yuling

    2018-02-01

    Chemical mechanical polishing (CMP) is one of the important machining procedures of multilayered copper interconnection for GLSI, meanwhile polishing slurry is a critical factor for realizing the high polishing performance such as high planarization efficiency, low surface roughness. The effect of slurry components such as abrasive (colloidal silica), complexing agent (glycine), inhibitor (BTA) and oxidizing agent (H2O2) on the stability of the novel weakly alkaline slurry of copper interconnection CMP for GLSI was investigated in this paper. First, the synergistic and competitive relationship of them in a peroxide-based weakly alkaline slurry during the copper CMP process was studied and the stability mechanism was put forward. Then 1 wt% colloidal silica, 2.5 wt% glycine, 200 ppm BTA, 20 mL/L H2O2 had been selected as the appropriate concentration to prepare copper slurry, and using such slurry the copper blanket wafer was polished. From the variations of copper removal rate, root-mean square roughness (Sq) value with the setting time, it indicates that the working-life of the novel weakly alkaline slurry can reach more than 7 days, which satisfies the requirement of microelectronics further development. Project supported by the Major National Science and Technology Special Projects (No. 2016ZX02301003-004-007), the Professional Degree Teaching Case Foundation of Hebei Province, China (No. KCJSZ2017008), the Natural Science Foundation of Hebei Province, China (No. F2015202267), and the Natural Science Foundation of Tianjin, China (No. 16JCYBJC16100).

  1. Soil-bentonite design mix for slurry cutoff walls used as containment barriers

    International Nuclear Information System (INIS)

    Rad, N.S.; Bachus, R.C.; Jacobson, B.D.

    1995-01-01

    In recent years, soil-bentonite slurry cutoff walls have been increasingly used as containment barriers around contaminated soils to impede or, in some cases, nearly eliminate the off-site migration of contaminated ground water or other potentially hazardous liquids. The paper presents the procedures used and the results obtained during an extensive laboratory testing program performed to select varying soil-bentonite slurry mix components for a soil-bentonite slurry cutoff wall constructed around an old landfill at a former oil refinery. The landfill is underlain to varying depths by a coarse granular soils that has been exposed to oil-products. Compatibility of three commercially available bentonite products with the free oil-products and the oil-contaminated ground water found at some locations in the landfill was initially investigated. Based on the test results, one of the bentonite products was selected for use in the soil-bentonite slurry testing program. A clayey soil from a borrow source, potable water from the site, and subsurface soils from the proposed soil-bentonite slurry wall alignment were used to form different soil-bentonite slurry mixes. Slump tests were performed to evaluate the workability of the mixes. Based on the test results, a single mix was selected for further study, including permeability/compatibility testing. The results of the compatibility testing program are presented and discussed in the paper. A specific design mix methodology for evaluating the chemical compatibility of soil-bentonite slurry mixes with permeants is proposed

  2. Experimental study of a metal hydride driven braided artificial pneumatic muscle

    Science.gov (United States)

    Vanderhoff, Alexandra; Kim, Kwang J.

    2009-12-01

    This paper reports the experimental study of a new actuation system that couples a braided artificial pneumatic muscle (BAPM) with a metal hydride driven hydrogen compressor to create a compact, lightweight, noiseless system capable of high forces and smooth actuation. The results indicate that the metal hydride-BAPM system has relatively good second law efficiency average of 30% over the desorption cycle. The thermal efficiency is low, due mainly to the highly endothermic chemical reaction that releases the stored hydrogen gas from the metal hydride. The force to metal hydride weight is very high (~14 000 NForce/kgMH) considering that this system has not been optimized to use the minimum amount of metal hydride required for a full actuation stroke of the fluidic muscle. Also, a thermodynamic model for the complete system is developed. The analysis is restricted in some aspects concerning the complexity of the hydriding/dehydriding chemical process of the system and the three-dimensional geometry of the reactor, but it provides a useful comparison to other actuation devices and clearly reveals the parameters necessary for optimization of the actuation system in future work. The system shows comparable work output and has the benefits of biological muscle-like properties for potential use in robotic systems.

  3. Synthesis, spectroscopy, and hydrogen/deuterium exchange in high-spin iron(II) hydride complexes.

    Science.gov (United States)

    Dugan, Thomas R; Bill, Eckhard; MacLeod, K Cory; Brennessel, William W; Holland, Patrick L

    2014-03-03

    Very few hydride complexes are known in which the metals have a high-spin electronic configuration. We describe the characterization of several high-spin iron(II) hydride/deuteride isotopologues and their exchange reactions with one another and with H2/D2. Though the hydride/deuteride signal is not observable in NMR spectra, the choice of isotope has an influence on the chemical shifts of distant protons in the dimers through the paramagnetic isotope effect on chemical shift. This provides the first way to monitor the exchange of H and D in the bridging positions of these hydride complexes. The rate of exchange depends on the size of the supporting ligand, and this is consistent with the idea that H2/D2 exchange into the hydrides occurs through the dimeric complexes rather than through a transient monomer. The understanding of H/D exchange mechanisms in these high-spin iron hydride complexes may be relevant to postulated nitrogenase mechanisms.

  4. Complex hydrides for hydrogen storage

    Science.gov (United States)

    Zidan, Ragaiy

    2006-08-22

    A hydrogen storage material and process of forming the material is provided in which complex hydrides are combined under conditions of elevated temperatures and/or elevated temperature and pressure with a titanium metal such as titanium butoxide. The resulting fused product exhibits hydrogen desorption kinetics having a first hydrogen release point which occurs at normal atmospheres and at a temperature between 50.degree. C. and 90.degree. C.

  5. Use of reversible hydrides for hydrogen storage

    Science.gov (United States)

    Darriet, B.; Pezat, M.; Hagenmuller, P.

    1980-01-01

    The addition of metals or alloys whose hydrides have a high dissociation pressure allows a considerable increase in the hydrogenation rate of magnesium. The influence of temperature and hydrogen pressure on the reaction rate were studied. Results concerning the hydriding of magnesium rich alloys such as Mg2Ca, La2Mg17 and CeMg12 are presented. The hydriding mechanism of La2Mg17 and CeMg12 alloys is given.

  6. NMR study of hydride systems

    International Nuclear Information System (INIS)

    Peretz, M.

    1980-02-01

    The hydrides of thorium (ThH 2 , Th 4 H 15 and Th 4 D 15 ) and the intermetallic compound system (Zr(Vsub(1-x)Cosub(x)) 2 and its hydrides were investigated using the nuclear magnetic resonance (NMR) technique. From the results for the thorium hydride samples it was concluded that the density of states at the Fermi level n(Esub(f)) is higher in Th 4 H 15 than in ThH 2 ; there is an indirect reaction between the protons and the d electrons belonging to the Th atoms in Th 4 H 15 ; n(E) has a sharp structure near Esub(f). It was also found that the hydrogen diffusion mechanism changes with temperature. From the results for the intermetallic compound system conclusions were drawn concerning variations in the electronic structure, which explain the behavior of the system. In hydrogen diffusion studies in several samples it was found that Co atoms slow the diffusion rate. Quadrupole spectra obtained at low temperatures show that the H atoms preferably occupy tetrahedral sites formed by three V atoms and one Z atom. (H.K.)

  7. Secondary hydriding of defected zircaloy-clad fuel rods

    International Nuclear Information System (INIS)

    Olander, D.R.; Vaknin, S.

    1993-01-01

    The phenomenon of secondary hydriding in LWR fuel rods is critically reviewed. The current understanding of the process is summarized with emphasis on the sources of hydrogen in the rod provided by chemical reaction of water (steam) introduced via a primary defect in the cladding. As often noted in the literature, the role of hydrogen peroxide produced by steam radiolysis is to provide sources of hydrogen by cladding and fuel oxidation that are absent without fission-fragment irradiation of the gas. Quantitative description of the evolution of the chemical state inside the fuel rod is achieved by combining the chemical kinetics of the reactions between the gas and the fuel and cladding with the transport by diffusion of components of the gas in the gap. The chemistry-gas transport model provides the framework into which therate constants of the reactions between the gases in the gap and the fuel and cladding are incorporated. The output of the model calculation is the H 2 0/H 2 ratio in the gas and the degree of claddingand fuel oxidation as functions of distance from the primary defect. This output, when combined with a criterion for the onset of massive hydriding of the cladding, can provide a prediction of the time and location of a potential secondary hydriding failure. The chemistry-gas transport model is the starting point for mechanical and H-in-Zr migration analyses intended to determine the nature of the cladding failure caused by the development of the massive hydride on the inner wall

  8. Fundamental experiments on hydride reorientation in zircaloy

    Science.gov (United States)

    Colas, Kimberly B.

    In the current study, an in-situ X-ray diffraction technique using synchrotron radiation was used to follow directly the kinetics of hydride dissolution and precipitation during thermomechanical cycles. This technique was combined with conventional microscopy (optical, SEM and TEM) to gain an overall understanding of the process of hydride reorientation. Thus this part of the study emphasized the time-dependent nature of the process, studying large volume of hydrides in the material. In addition, a micro-diffraction technique was also used to study the spatial distribution of hydrides near stress concentrations. This part of the study emphasized the spatial variation of hydride characteristics such as strain and morphology. Hydrided samples in the shape of tensile dog-bones were used in the time-dependent part of the study. Compact tension specimens were used during the spatial dependence part of the study. The hydride elastic strains from peak shift and size and strain broadening were studied as a function of time for precipitating hydrides. The hydrides precipitate in a very compressed state of stress, as measured by the shift in lattice spacing. As precipitation proceeds the average shift decreases, indicating average stress is reduced, likely due to plastic deformation and morphology changes. When nucleation ends the hydrides follow the zirconium matrix thermal contraction. When stress is applied below the threshold stress for reorientation, hydrides first nucleate in a very compressed state similar to that of unstressed hydrides. After reducing the average strain similarly to unstressed hydrides, the average hydride strain reaches a constant value during cool-down to room temperature. This could be due to a greater ease of deforming the matrix due to the applied far-field strain which would compensate for the strains due to thermal contraction. Finally when hydrides reorient, the average hydride strains become tensile during the first precipitation regime and

  9. Production of propylene from 1-butene on highly active "bi-functional single active site" catalyst: Tungsten carbene-hydride supported on alumina

    KAUST Repository

    Mazoyer, Etienne

    2011-12-02

    1-Butene is transformed in a continuous flow reactor over tungsten hydrides precursor W-H/Al2O3, 1, giving a promising yield into propylene at 150 °C and different pressures. Tungsten carbene-hydride single active site operates as a "bi-functional catalyst" through 1-butene isomerization on W-hydride and 1-butene/2-butenes cross-metathesis on W-carbene. This active moiety is generated in situ at the initiation steps by insertion of 1-butene on tungsten hydrides precursor W-H/Al2O3, 1 followed by α-H and β-H abstraction. © 2011 American Chemical Society.

  10. Advanced computational model for three-phase slurry reactors

    International Nuclear Information System (INIS)

    Goodarz Ahmadi

    2001-10-01

    In the second year of the project, the Eulerian-Lagrangian formulation for analyzing three-phase slurry flows in a bubble column is further developed. The approach uses an Eulerian analysis of liquid flows in the bubble column, and makes use of the Lagrangian trajectory analysis for the bubbles and particle motions. An experimental set for studying a two-dimensional bubble column is also developed. The operation of the bubble column is being tested and diagnostic methodology for quantitative measurements is being developed. An Eulerian computational model for the flow condition in the two-dimensional bubble column is also being developed. The liquid and bubble motions are being analyzed and the results are being compared with the experimental setup. Solid-fluid mixture flows in ducts and passages at different angle of orientations were analyzed. The model predictions were compared with the experimental data and good agreement was found. Gravity chute flows of solid-liquid mixtures is also being studied. Further progress was also made in developing a thermodynamically consistent model for multiphase slurry flows with and without chemical reaction in a state of turbulent motion. The balance laws are obtained and the constitutive laws are being developed. Progress was also made in measuring concentration and velocity of particles of different sizes near a wall in a duct flow. The technique of Phase-Doppler anemometry was used in these studies. The general objective of this project is to provide the needed fundamental understanding of three-phase slurry reactors in Fischer-Tropsch (F-T) liquid fuel synthesis. The other main goal is to develop a computational capability for predicting the transport and processing of three-phase coal slurries. The specific objectives are: (1) To develop a thermodynamically consistent rate-dependent anisotropic model for multiphase slurry flows with and without chemical reaction for application to coal liquefaction. Also establish the

  11. Advanced computational model for three-phase slurry reactors

    International Nuclear Information System (INIS)

    Goodarz Ahmadi

    2000-11-01

    In the first year of the project, solid-fluid mixture flows in ducts and passages at different angle of orientations were analyzed. The model predictions are compared with the experimental data and good agreement was found. Progress was also made in analyzing the gravity chute flows of solid-liquid mixtures. An Eulerian-Lagrangian formulation for analyzing three-phase slurry flows in a bubble column is being developed. The approach uses an Eulerian analysis of gas liquid flows in the bubble column, and makes use of the Lagrangian particle tracking procedure to analyze the particle motions. Progress was also made in developing a rate dependent thermodynamically consistent model for multiphase slurry flows in a state of turbulent motion. The new model includes the effect of phasic interactions and leads to anisotropic effective phasic stress tensors. Progress was also made in measuring concentration and velocity of particles of different sizes near a wall in a duct flow. The formulation of a thermodynamically consistent model for chemically active multiphase solid-fluid flows in a turbulent state of motion was also initiated. The general objective of this project is to provide the needed fundamental understanding of three-phase slurry reactors in Fischer-Tropsch (F-T) liquid fuel synthesis. The other main goal is to develop a computational capability for predicting the transport and processing of three-phase coal slurries. The specific objectives are: (1) To develop a thermodynamically consistent rate-dependent anisotropic model for multiphase slurry flows with and without chemical reaction for application to coal liquefaction. Also to establish the material parameters of the model. (2) To provide experimental data for phasic fluctuation and mean velocities, as well as the solid volume fraction in the shear flow devices. (3) To develop an accurate computational capability incorporating the new rate-dependent and anisotropic model for analyzing reacting and

  12. Very low conductivity self-hardening slurry for permanent enclosures

    International Nuclear Information System (INIS)

    Tallard, G.

    1997-01-01

    Attapulgite clay and ground blast furnace slag cement can form a low solids slurry which, after setting and curing, exhibits very low permeability and substantial strength. Compared to better known cement bentonite slurries, the conductivity is 3 orders of magnitude lower and the strength is four times higher at a similar solids content. Coefficients of permeability have been measured in the 10 -10 cm/sec. range. As a containment barrier, no chemical compound has had detrimental effects on the integrity of the material. Compatibility with leachates at a pH under 2 has been demonstrated. Compared to leachable Ordinary Portland Cement and to bentonite gel shrinkage in the presence of certain organic compounds, the attapulgite clay and the selected slag cement behave as remarkably inert. A number of successful applications as vertical barriers, trenched and by the vibrated beam method, have been installed at remedial sites. Applications by jet grouting have been implemented under utilities to provide continuity. The potential for placement of such materials to form horizontal barriers by jet grouting or frac-grouting/mud jacking techniques, offers the possibility of creating complete enclosures in soils. The purely mineral nature of these slurries ensures long term chemical stability necessary for permanent containment

  13. Single stage high pressure centrifugal slurry pump

    Science.gov (United States)

    Meyer, John W.; Bonin, John H.; Daniel, Arnold D.

    1984-03-27

    Apparatus is shown for feeding a slurry to a pressurized housing. An impeller that includes radial passages is mounted in the loose fitting housing. The impeller hub is connected to a drive means and a slurry supply means which extends through the housing. Pressured gas is fed into the housing for substantially enveloping the impeller in a bubble of gas.

  14. Slurry discharge management-beach profile prediction

    Energy Technology Data Exchange (ETDEWEB)

    Bravo, R.; Nawrot, J.R. [Southern Illinois University at Carbondale, Carbondale, IL (United States). Dept. of Civil Engineering

    1996-11-01

    Mine tailings dams are embankments used by the mining industry to retain the tailings products after the mineral preparation process. Based on the acid-waste stereotype that all coal slurry is acid producing, current reclamation requires a four foot soil cover for inactive slurry disposal areas. Compliance with this requirement is both difficult and costly and in some case unnecessary, as not all the slurry, or portions of slurry impoundments are acid producing. Reduced costs and recent popularity of wetland development has prompted many operators to request reclamation variances for slurry impoundments. Waiting to address slurry reclamation until after the impoundment is full, limits the flexibility of reclamation opportunities. This paper outlines a general methodology to predict the formation of the beach profile for mine tailings dams, by the discharge volume and location of the slurry into the impoundment. The review is presented under the perspective of geotechnical engineering and waste disposal management emphasizing the importance of pre-planning slurry disposal land reclamation. 4 refs., 5 figs.

  15. High temperature oxidation of slurry coated interconnect alloys

    DEFF Research Database (Denmark)

    Persson, Åsa Helen

    with this interaction mechanism mainly give a geometrical protection against oxidation by blocking oxygen access at the surface of the oxide scale. The protecting effect is gradually reduced as the oxide scale grows thicker than the diameter of the coating particles. Interaction mechanism B entails a chemical reaction...... scale. The incorporated coating particles create a geometrical protection against oxidation that should not loose their effect after the oxide scale has grown thicker than the diameter of the coating particles. The two single layer coatings consisting of (La0.85Sr0.15)MnO3 + 10% excess Mn, LSM, and (La0......In this project, high temperature oxidation experiments of slurry coated ferritic alloys in atmospheres similar to the atmosphere found at the cathode in an SOFC were conducted. From the observations possible interaction mechanisms between the slurry coatings and the growing oxide scale...

  16. Studies on Slurry Design Fundamentals for Advanced CMP Applications

    KAUST Repository

    Basim, G. B.

    2013-06-14

    New developments and device performance requirements in microelectronics industry add to the challenges in chemical mechanical planarization (CMP) process. One of the recently introduced materials is germanium which enables improved performance through better channel mobility in shallow trench isolation (STI) applications. This paper reports on the slurry design alternatives for Ge CMP with surfactant mediation to improve on the silica/germanium selectivity using colloidal silica slurry. In addition to the standard CMP tests to evaluate the material removal rates, atomic force microscopy (AFM) based wear tests were also conducted to evaluate single particle-surface interaction of the polishing system. Furthermore, nature of the surface oxide film of germanium was studied through contact angle measurements and surface roughness tested by AFM. It was observed that the CMP selectivity of the silica/germanium system and defectivity control were possible with a reasonable material removal rate value by using self-assembled structures of cationic surfactants.

  17. Studies on Slurry Design Fundamentals for Advanced CMP Applications

    KAUST Repository

    Basim, G. B.; Karagoz, A.; Ozdemir, Z.; Vakarelski, Ivan Uriev; Chen, Long

    2013-01-01

    New developments and device performance requirements in microelectronics industry add to the challenges in chemical mechanical planarization (CMP) process. One of the recently introduced materials is germanium which enables improved performance through better channel mobility in shallow trench isolation (STI) applications. This paper reports on the slurry design alternatives for Ge CMP with surfactant mediation to improve on the silica/germanium selectivity using colloidal silica slurry. In addition to the standard CMP tests to evaluate the material removal rates, atomic force microscopy (AFM) based wear tests were also conducted to evaluate single particle-surface interaction of the polishing system. Furthermore, nature of the surface oxide film of germanium was studied through contact angle measurements and surface roughness tested by AFM. It was observed that the CMP selectivity of the silica/germanium system and defectivity control were possible with a reasonable material removal rate value by using self-assembled structures of cationic surfactants.

  18. Comparison and analysis of organic components of biogas slurry from eichhornia crassipes solms and corn straw biogas slurry

    Science.gov (United States)

    Li, Q.; Li, Y. B.; Liu, Z. H.; Min, J.; Cui, Y.; Gao, X. H.

    2017-11-01

    Biogas slurry is one of anaerobic fermentations, and biomass fermentation biogas slurries with different compositions are different. This paper mainly presents through the anaerobic fermentation of Eichhornia crassipes solms biogas slurry and biogas slurry of corn straw, the organic components of two kinds of biogas slurry after extraction were compared by TLC, HPLC and spectrophotometric determination of nucleic acid and protein of two kinds of biogas slurry organic components, and analyzes the result of comparison.

  19. ON THE CHEMISTRY OF HYDRIDES OF N ATOMS AND O{sup +} IONS

    Energy Technology Data Exchange (ETDEWEB)

    Awad, Zainab [Astronomy, Space Science, and Meteorology Department, Faculty of Science, Cairo University, Giza (Egypt); Viti, Serena; Williams, David A., E-mail: zma@sci.cu.edu.eg [Physics and Astronomy Department, University College London, Gower Street, London WC1E 6BT (United Kingdom)

    2016-08-01

    Previous work by various authors has suggested that the detection by Herschel /HIFI of nitrogen hydrides along the low-density lines of sight toward G10.6-0.4 (W31C) cannot be accounted for by gas-phase chemical models. In this paper we investigate the role of surface reactions on dust grains in diffuse regions, and we find that formation of the hydrides by surface reactions on dust grains with efficiency comparable to that for H{sub 2} formation reconciles models with observations of nitrogen hydrides. However, similar surface reactions do not contribute significantly to the hydrides of O{sup +} ions detected by Herschel /HIFI that are present along many sight lines in the Galaxy. The O{sup +} hydrides can be accounted for by conventional gas-phase chemistry either in diffuse clouds of very low density with normal cosmic-ray fluxes or in somewhat denser diffuse clouds with high cosmic-ray fluxes. Hydride chemistry in dense dark clouds appears to be dominated by gas-phase ion–molecule reactions.

  20. On the Chemistry of Hydrides of N Atoms and O+ Ions

    Science.gov (United States)

    Awad, Zainab; Viti, Serena; Williams, David A.

    2016-08-01

    Previous work by various authors has suggested that the detection by Herschel/HIFI of nitrogen hydrides along the low-density lines of sight toward G10.6-0.4 (W31C) cannot be accounted for by gas-phase chemical models. In this paper we investigate the role of surface reactions on dust grains in diffuse regions, and we find that formation of the hydrides by surface reactions on dust grains with efficiency comparable to that for H2 formation reconciles models with observations of nitrogen hydrides. However, similar surface reactions do not contribute significantly to the hydrides of O+ ions detected by Herschel/HIFI that are present along many sight lines in the Galaxy. The O+ hydrides can be accounted for by conventional gas-phase chemistry either in diffuse clouds of very low density with normal cosmic-ray fluxes or in somewhat denser diffuse clouds with high cosmic-ray fluxes. Hydride chemistry in dense dark clouds appears to be dominated by gas-phase ion-molecule reactions.

  1. Manufacture of titanium and zirconium hydrides

    International Nuclear Information System (INIS)

    Mares, F.; Hanslik, T.

    1973-01-01

    A method is described of manufacturing titanium and zirconium hydrides by hydrogenation of said metals characterized by the reaction temperature ranging between 250 to 500 degC, hydrogen pressure of 20 to 300 atm and possibly by the presence of a hydride of the respective metal. (V.V.)

  2. Hydride effect on crack instability of Zircaloy cladding

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Che-Chung, E-mail: cctseng@iner.gov.tw [Institute of Nuclear Energy Research, No. 1000, Wunhua Road, Jiaan Village, Lungtan, Township, Taoyuan County 32546, Taiwan (China); Sun, Ming-Hung [Institute of Nuclear Energy Research, No. 1000, Wunhua Road, Jiaan Village, Lungtan, Township, Taoyuan County 32546, Taiwan (China); Chao, Ching-Kong [Department of Mechanical Engineering, National Taiwan University of Science and Technology, 43 Keelung Road, Section 4, Taipei 106, Taiwan (China)

    2014-04-01

    Highlights: • Radial hydrides near the crack tip had a significant effect on crack propagation. • For radial hydrides off the crack line vertically, the effect on crack propagation was notably reduced. • The longer hydride platelet resulted in a remarkable effect on crack propagation. • A long split in the radial hydride precipitate would enhance crack propagation. • The presence of circumferential hydride among radial hydrides may play an important role in crack propagation. - Abstract: A methodology was proposed to investigate the effect of hydride on the crack propagation in fuel cladding. The analysis was modeled based on an outside-in crack with radial hydrides located near its crack tip. The finite element method was used in the calculation; both stress intensity factor K{sub I} and J integral were applied to evaluate the crack stability. The parameters employed in the analysis included the location of radial hydride, hydride dimensions, number of hydrides, and the presence of circumferential hydride, etc. According to our study, the effective distance between a radial hydride and the assumed cladding surface crack for the enhancement of crack propagation proved to be no greater than 0.06 mm. For a hydride not on the crack line, it would induce a relatively minor effect on crack propagation if the vertical distance was beyond 0.05 mm. However, a longer hydride precipitate as well as double radial hydrides could have a remarkable effect on crack propagation. A combined effect of radial and circumferential hydrides was also discussed.

  3. Equilibrium composition for the reaction of plutonium hydride with air

    International Nuclear Information System (INIS)

    Zou Lexi; Sun Ying; Xue Weidong; Zhu Zhenghe; Wang Rong; Luo Deli

    2002-01-01

    There are six independent constituents with 4 chemical elements, i.e. PuH 2.7 (s), PuN(s), Pu 2 O 3 (s), N 2 , O 2 and H 2 , therefore, the system described involves of 2 independent reactions, both ΔG 0 <<0. The calculated equilibrium compositions are in agreement with those of the experimental, which indicates that the chemical equilibrium is nearly completely approached. Therefore, it is believed that the reaction rate of plutonium hydride with air is extremely rapid. The author has briefly discussed the simultaneous reactions and its thermodynamic coupling effect

  4. Chemical treatment of acid mining lakes in the Lausitz region. Experience with lime slurry resuspension in Koschen lake; Die chemische Behandlung saurer Tagebauseen in der Lausitz. Erfahrungen zur Kalkschlammresuspension im Tagebausee Koschen

    Energy Technology Data Exchange (ETDEWEB)

    Benthaus, F.C. [Lausitzer und Mitteldeutsche Bergbauverwaltungs-Gesellschaft mbH, Senftenberg (Germany); Uhlmann, W. [Institut fuer Wasser und Boden Dr. Uhlmann, Dresden (Germany)

    2006-07-01

    Acidic groundwater from catchments areas at mining lakes in the Lausitz basin causes negative effects on water quality. Those do not fit to existing standards and does not correspond to further use of mining lakes. Most of the lakes are to be filled by surface waters from nearby rivers and creeks. Cause of the limited availability of flooding water a hydrochemical treatment of water bodies is necessary. In order to apply modern techniques, the LMBV company support partners to develop new procedures. The LMBV evaluates the results of R+D projects on applications to reach the objectives with high efficiency, sustainability and cost effectiveness. At the Koschen lake, limestone slurry of a former treatment plant had to be moved because of stability reasons. In order to ameliorate the water quality in the lake, this slurry deposit had been mixed to a 540,000 m{sup 3} suspension and used as neutralising agent. Wind effects had been used to spread the agent all over the water body. While running this project in 2004 and 2005, the lake had been filled simultaneously with about 9 Mio. m{sup 3} of surface waters. Hydrochemical modelling, based on a monitoring program, allows demonstrating the effects of the treatment as well as the filling process. The increase of alkalinity gained by treatment and by filling was about +0.7 eq/m{sup 3} respectively +0.2 eq/m{sup 3}. Together they allow ameliorating the water body by economic means. (orig.)

  5. Obtaining zircaloy powder through hydriding

    International Nuclear Information System (INIS)

    Dupim, Ivaldete da Silva; Moreira, Joao M.L.

    2009-01-01

    Zirconium alloys are good options for the metal matrix in dispersion fuels for power reactors due to their low thermal neutron absorption cross-section, good corrosion resistance, good mechanical strength and high thermal conductivity. A necessary step for obtaining such fuels is producing Zr alloy powder for the metal matrix composite material. This article presents results from the Zircaloy-4 hydrogenation tests with the purpose to embrittle the alloy as a first step for comminuting. Several hydrogenation tests were performed and studied through thermogravimetric analysis. They included H 2 pressures of 25 and 50 kPa and temperatures ranging between from 20 to 670 deg C. X-ray diffraction analysis showed in the hydrogenated samples the predominant presence of ZrH 2 and some ZrO 2 . Some kinetics parameters for the Zircaloy-4 hydrogenation reaction were obtained: the time required to reach the equilibrium state at the dwell temperature was about 100 minutes; the hydrogenation rate during the heating process from 20 to 670 deg C was about 21 mg/h, and at constant temperature of 670 deg C, the hydride rate was about 1.15 mg/h. The hydrogenation rate is largest during the heating process and most of it occurs during this period. After hydrogenated, the samples could easily be comminuted indicating that this is a possible technology to obtain Zircaloy powder. The results show that only few minutes of hydrogenation are necessary to reach the hydride levels required for comminuting the Zircaloy. The final hydride stoichiometry was between 2.7 and 2.8 H for each Zr atom in the sample (author)

  6. Zirconium hydride containing explosive composition

    Science.gov (United States)

    Walker, Franklin E.; Wasley, Richard J.

    1981-01-01

    An improved explosive composition is disclosed and comprises a major portion of an explosive having a detonation velocity between about 1500 and 10,000 meters per second and a minor amount of a donor additive comprising a non-explosive compound or mixture of non-explosive compounds which when subjected to an energy fluence of 1000 calories/cm.sup.2 or less is capable of releasing free radicals each having a molecular weight between 1 and 120. Exemplary donor additives are dibasic acids, polyamines and metal hydrides.

  7. Proton and hydride affinities in excited states: magnitude reversals in proton and hydride affinities between the lowest singlet and triplet states of annulenyl and benzannulenyl anions and cations

    DEFF Research Database (Denmark)

    Rosenberg, Martin; Ottosson, Henrik; Kilså, Kristine

    2010-01-01

    electron counting rules for aromaticity in the two states. Using quantum chemical calculations at the G3(MP2)//(U)B3LYP/6-311+G(d,p) level we have examined the validity of this hypothesis for eight proton and eight hydride addition reactions of anions and cations, respectively, of annulenyl...

  8. Metal Hydrides for Rechargeable Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Valoeen, Lars Ole

    2000-03-01

    Rechargeable battery systems are paramount in the power supply of modern electronic and electromechanical equipment. For the time being, the most promising secondary battery systems for the future are the lithium-ion and the nickel metal hydride (NiMH) batteries. In this thesis, metal hydrides and their properties are described with the aim of characterizing and improving those. The thesis has a special focus on the AB{sub 5} type hydrogen storage alloys, where A is a rare earth metal like lanthanum, or more commonly misch metal, which is a mixture of rare earth metals, mainly lanthanum, cerium, neodymium and praseodymium. B is a transition metal, mainly nickel, commonly with additions of aluminium, cobalt, and manganese. The misch metal composition was found to be very important for the geometry of the unit cell in AB{sub 5} type alloys, and consequently the equilibrium pressure of hydrogen in these types of alloys. The A site substitution of lanthanum by misch metal did not decrease the surface catalytic properties of AB{sub 5} type alloys. B-site substitution of nickel with other transition elements, however, substantially reduced the catalytic activity of the alloy. If the internal pressure within the electrochemical test cell was increased using inert argon gas, a considerable increase in the high rate charge/discharge performance of LaNi{sub 5} was observed. An increased internal pressure would enable the utilisation of alloys with a high hydrogen equivalent pressure in batteries. Such alloys often have favourable kinetics and high hydrogen diffusion rates and thus have a potential for improving the high current discharge rates in metal hydride batteries. The kinetic properties of metal hydride electrodes were found to improve throughout their lifetime. The activation properties were found highly dependent on the charge/discharge current. Fewer charge/discharge cycles were needed to activate the electrodes if a small current was used instead of a higher

  9. Hydrogen-storing hydride complexes

    Science.gov (United States)

    Srinivasan, Sesha S [Tampa, FL; Niemann, Michael U [Venice, FL; Goswami, D Yogi [Tampa, FL; Stefanakos, Elias K [Tampa, FL

    2012-04-10

    A ternary hydrogen storage system having a constant stoichiometric molar ratio of LiNH.sub.2:MgH.sub.2:LiBH.sub.4 of 2:1:1. It was found that the incorporation of MgH.sub.2 particles of approximately 10 nm to 20 nm exhibit a lower initial hydrogen release temperature of 150.degree. C. Furthermore, it is observed that the particle size of LiBNH quaternary hydride has a significant effect on the hydrogen sorption concentration with an optimum size of 28 nm. The as-synthesized hydrides exhibit two main hydrogen release temperatures, one around 160.degree. C. and the other around 300.degree. C., with the main hydrogen release temperature reduced from 310.degree. C. to 270.degree. C., while hydrogen is first reversibly released at temperatures as low as 150.degree. C. with a total hydrogen capacity of 6 wt. % to 8 wt. %. Detailed thermal, capacity, structural and microstructural properties have been demonstrated and correlated with the activation energies of these materials.

  10. Activated aluminum hydride hydrogen storage compositions and uses thereof

    Science.gov (United States)

    Sandrock, Gary; Reilly, James; Graetz, Jason; Wegrzyn, James E.

    2010-11-23

    In one aspect, the invention relates to activated aluminum hydride hydrogen storage compositions containing aluminum hydride in the presence of, or absence of, hydrogen desorption stimulants. The invention particularly relates to such compositions having one or more hydrogen desorption stimulants selected from metal hydrides and metal aluminum hydrides. In another aspect, the invention relates to methods for generating hydrogen from such hydrogen storage compositions.

  11. Hydrogen adsorption on palladium and palladium hydride at 1 bar

    DEFF Research Database (Denmark)

    Johansson, Martin; Skulason, Egill; Nielsen, Gunver

    2010-01-01

    strongly to Pd hydride than to Pd. The activation barrier for desorption at a H coverage of one mono layer is slightly lower on Pd hydride, whereas the activation energy for adsorption is similar on Pd and Pd hydride. It is concluded that the higher sticking probability on Pd hydride is most likely caused...

  12. Cyclopentadiene-mediated hydride transfer from rhodium complexes.

    Science.gov (United States)

    Pitman, C L; Finster, O N L; Miller, A J M

    2016-07-12

    Attempts to generate a proposed rhodium hydride catalytic intermediate instead resulted in isolation of (Cp*H)Rh(bpy)Cl (1), a pentamethylcyclopentadiene complex, formed by C-H bond-forming reductive elimination from the fleeting rhodium hydride. The hydride transfer ability of diene 1 was explored through thermochemistry and hydride transfer reactions, including the reduction of NAD(+).

  13. Biogas slurry utilization in Ghana

    Energy Technology Data Exchange (ETDEWEB)

    Asser, C. [Ministry of Mines and Energy, Accra (Ghana)

    1999-07-01

    The biogas Technology Programme developed for villages remote from the national grid relies solely on cow-dung and human waste as raw materials for electricity generation. The technology helps control deforestation and desertification and reduces the long hours spent looking for fuelwood for cooking and the health risk that smoke from fuelwood poses. Rural electricity generation also supplies pipe-borne water, community toilets and organic fertilizer for farmers. The slurry, which is the by-product of the biogas, is an odourless, pathogen free organic fertilizer that is high in nitrogen, phosphorous and potassium. It is useful for crop production, fish farming and mushroom cultivation. Farmers now realize that energy can be extracted from cowdung, human waste, agricultural residue and other biomass resources and the biomass can still maintain its function as good organic manure. (author)

  14. Oxygen transfer in slurry bioreactors.

    Science.gov (United States)

    Kawase, Y; Moo-Young, M

    1991-04-25

    The oxygen transfer in bioreactors with slurries having a yield stress was investigated. The volumetric mass transfer coefficients in a 40-L bubble column with simulated fermentation broths, the Theological properties of which were represented by the Casson model, were measured. Experimental data were compared with a theoretical correlation developed on the basis of a combination of Higbie's penetration theory and Kolmogoroff's theory of isotropic turbulence. Comparisons between the proposed correlation and data for the simulated broths show good agreement. The mass transfer data for actual mycelial fermentation broths reported previously by the authors were re-examined. Their Theological data was correlated by the Bingham plastic model. The oxygen transfer rate data in the mycelial fermentation broths fit the predictions of the proposed theoretical correlation.

  15. Hydrogen Storage using Metal Hydrides in a Stationary Cogeneration System

    International Nuclear Information System (INIS)

    Botzung, Maxime; Chaudourne, Serge; Perret, Christian; Latroche, Michel; Percheron-Guegan, Annick; Marty Philippe

    2006-01-01

    In the frame of the development of a hydrogen production and storage unit to supply a 40 kW stationary fuel cell, a metal hydride storage tank was chosen according to its reliability and high energetic efficiency. The study of AB5 compounds led to the development of a composition adapted to the project needs. The absorption/desorption pressures of the hydride at 75 C (2 / 1.85 bar) are the most adapted to the specifications. The reversible storage capacity (0.95 %wt) has been optimized to our work conditions and chemical kinetics is fast. The design of the Combined Heat and Power CHP system requires 5 kg hydrogen storage but in a first phase, only a 0.1 kg prototype has been realised and tested. Rectangular design has been chosen to obtain good compactness with an integrated plate fin type heat exchanger designed to reach high absorption/desorption rates. In this paper, heat and mass transfer characteristics of the Metal Hydride tank (MH tank) during absorption/desorption cycles are given. (authors)

  16. Process for heating coal-oil slurries

    Science.gov (United States)

    Braunlin, W.A.; Gorski, A.; Jaehnig, L.J.; Moskal, C.J.; Naylor, J.D.; Parimi, K.; Ward, J.V.

    1984-01-03

    Controlling gas to slurry volume ratio to achieve a gas holdup of about 0.4 when heating a flowing coal-oil slurry and a hydrogen containing gas stream allows operation with virtually any coal to solvent ratio and permits operation with efficient heat transfer and satisfactory pressure drops. The critical minimum gas flow rate for any given coal-oil slurry will depend on numerous factors such as coal concentration, coal particle size distribution, composition of the solvent (including recycle slurries), and type of coal. Further system efficiency can be achieved by operating with multiple heating zones to provide a high heat flux when the apparent viscosity of the gas saturated slurry is highest. Operation with gas flow rates below the critical minimum results in system instability indicated by temperature excursions in the fluid and at the tube wall, by a rapid increase and then decrease in overall pressure drop with decreasing gas flow rate, and by increased temperature differences between the temperature of the bulk fluid and the tube wall. At the temperatures and pressures used in coal liquefaction preheaters the coal-oil slurry and hydrogen containing gas stream behaves essentially as a Newtonian fluid at shear rates in excess of 150 sec[sup [minus]1]. The gas to slurry volume ratio should also be controlled to assure that the flow regime does not shift from homogeneous flow to non-homogeneous flow. Stable operations have been observed with a maximum gas holdup as high as 0.72. 29 figs.

  17. Management of Biogas spent slurry for hastening the composting of agro residues

    Directory of Open Access Journals (Sweden)

    G. S. Geeta

    2015-04-01

    Full Text Available The demand for energy and the fertilizers are ever increasing. Organic farming has many advantages looking to the environment pollution, unproductive soil, less yields etc. By installation of a biogas plant serves both the purposes of meeting the fuel as well as obtaining manures. The organic manures need to be added in bulk to meet the nutrient demands of the crop as it is not in concentrated form like chemical fertilizers. Hence, biogas spent slurry is the best alternate for hastening the compost preparation of abundantly available crop residues as well as obtaining enriched compost as conventional method takes long time. Moreover, slurry is composed of major nutrients besides enzymes and a rich microflora. Based on the preliminary results, the present study was conducted at farmer’s field to know whether slurry could be used for degradation of agro residues. One ton of crop residues that included banana waste, sunflower and maize waste, leaf litter of horticultural crops were inoculated individually with 60 L of spent slurry along with consortia of degrading fungi and P-solubilising bacteria. After a retention period of 60 days, nutrients were analysed. The cultures along with slurry indicated 1.5 - 1.96% N with reduction in C:N ratio between 1.6 - 1.82. The micronutrients also increased. Thus, it was concluded that efficient use of spent slurry can be made besides utilising the crop residues and the product for organic cultivation.

  18. Dynamic NMR Study of Model CMP Slurry Containing Silica Particles as Abrasives

    Science.gov (United States)

    Odeh, F.; Al-Bawab, A.; Li, Y.

    2018-02-01

    Chemical mechanical planarization (CMP) should provide a good surface planarity with minimal surface defectivity. Since CMP slurries are multi-component systems, it is very important to understand the various processes and interactions taking place in such slurries. Several techniques have been employed for such task, however, most of them lack the molecular recognition to investigate molecular interactions without adding probes which in turn increase complexity and might alter the microenvironment of the slurry. Nuclear magnetic resonance (NMR) is a powerful technique that can be employed in such study. The longitudinal relaxation times (T1) of the different components of CMP slurries were measured using Spin Echo-NMR (SE-NMR) at a constant temperature. The fact that NMR is non-invasive and gives information on the molecular level gives more advantage to the technique. The model CMP slurry was prepared in D2O to enable monitoring of T1 for the various components' protons. SE-NMR provide a very powerful tool to study the various interactions and adsorption processes that take place in a model CMP silica based slurry which contains BTA and/or glycine and/or Cu+2 ions. It was found that BTA is very competitive towards complexation with Cu+2 ions and BTA-Cu complex adsorbs on silica surface.

  19. High static gel strength cement slurries for gas flow-laboratory surveys and case history

    Energy Technology Data Exchange (ETDEWEB)

    Suzart, J. Walter P.; Ribeiro, Danilo [Halliburton Company, Houston, TX (United States); Farias, A.C. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Pessoa, Laudemar [University of Adelaide (Australia). Math. Bachelor Master Petroleum Engineer

    2008-07-01

    Gas migration is a phenomenon involving fluid density control, well conditioning, good adherence of the cement slurry to the contacting surfaces, chemical-physical properties, cement hydration mechanisms, and the well's geometry. This problem is evident in several producing wells with a pressurized annulus. Recently, a trend of combining operational techniques with cement slurries capable of developing very high static gel strength (SGS) has developed. Slurry designs intended to confer high SGS almost always have greater rheologies. This can make it difficult to mix the slurry on surfaces or even move the slurry placement through the well, more so because gas-producing wells are typically deep and have complex geometry. This paper evaluates the industry's understanding of this problem. It compares the major solutions with current cement slurry designs and, in addition to the conventional specific gas well parameters, it emphasizes the high SGS and low rheologies on surface conditions. This study also documents the success and efficiency of cementing at a Brazilian sedimentary basin which was completed using designs recommended in this work. This paper does not consider the gas migration occurrence through the cementing matrix. (author)

  20. Thermophilic slurry-phase treatment of petroleum hydrocarbon waste sludges

    International Nuclear Information System (INIS)

    Castaldi, F.J.; Bombaugh, K.J.; McFarland, B.

    1995-01-01

    Chemoheterotrophic thermophilic bacteria were used to achieve enhanced hydrocarbon degradation during slurry-phase treatment of oily waste sludges from petroleum refinery operations. Aerobic and anaerobic bacterial cultures were examined under thermophilic conditions to assess the effects of mode of metabolism on the potential for petroleum hydrocarbon degradation. The study determined that both aerobic and anaerobic thermophilic bacteria are capable of growth on petroleum hydrocarbons. Thermophilic methanogenesis is feasible during the degradation of hydrocarbons when a strict anaerobic condition is achieved in a slurry bioreactor. Aerobic thermophilic bacteria achieved the largest apparent reduction in chemical oxygen demand, freon extractable oil, total and volatile solid,s and polycyclic aromatic hydrocarbons (PAHs) when treating oily waste sludges. The observed shift with time in the molecular weight distribution of hydrocarbon material was more pronounced under aerobic metabolic conditions than under strict anaerobic conditions. The changes in the hydrocarbon molecular weight distribution, infrared spectra, and PAH concentrations during slurry-phase treatment indicate that the aerobic thermophilic bioslurry achieved a higher degree of hydrocarbon degradation than the anaerobic thermophilic bioslurry during the same time period

  1. Life Cycle Assessment of Slurry Management Technologies

    DEFF Research Database (Denmark)

    Wesnæs, Marianne; Wenzel, Henrik; Petersen, Bjørn Molt

    This report contains the results of Life Cycle Assessments of two slurry management technologies - acidification and decentred incineration. The LCA foundation can be used by the contributing companies for evaluating the environmental sustainability of a specific technology from a holistic Life...... Cycle perspective. Through this the companies can evaluate the environmental benefits and disadvantages of introducing a specific technology for slurry management. From a societal perspective the results can contribute to a clarification of which slurry management technologies (or combination...... of technologies) having the largest potential for reducing the overall environmental impacts....

  2. Non-aqueous slurries used as thickeners

    Energy Technology Data Exchange (ETDEWEB)

    Hatfield, J C

    1982-04-07

    A non-aqueous slurry is described that is suitable for use as a thickener or viscosifier in oil or gas drilling, fracturing, flow diversion completion or workover fluids. The slurry comprises a water-soluble cellulose ether polymer, a water-insoluble liquid hydrocarbon, a non-ionic surfactant having an HLB of from 7 to 14, and an organo modified clay. There also is described a process for thickening or viscosifying a drilling, fracturing, flow diversion, completion or workover fluid. The use of the slurry prevents bumping during addition to aqueous fluids. (27 claims)

  3. Experimental study of a metal hydride driven braided artificial pneumatic muscle

    International Nuclear Information System (INIS)

    Vanderhoff, Alexandra; Kim, Kwang J

    2009-01-01

    This paper reports the experimental study of a new actuation system that couples a braided artificial pneumatic muscle (BAPM) with a metal hydride driven hydrogen compressor to create a compact, lightweight, noiseless system capable of high forces and smooth actuation. The results indicate that the metal hydride–BAPM system has relatively good second law efficiency average of 30% over the desorption cycle. The thermal efficiency is low, due mainly to the highly endothermic chemical reaction that releases the stored hydrogen gas from the metal hydride. The force to metal hydride weight is very high (∼14 000 N Force /kg MH ) considering that this system has not been optimized to use the minimum amount of metal hydride required for a full actuation stroke of the fluidic muscle. Also, a thermodynamic model for the complete system is developed. The analysis is restricted in some aspects concerning the complexity of the hydriding/dehydriding chemical process of the system and the three-dimensional geometry of the reactor, but it provides a useful comparison to other actuation devices and clearly reveals the parameters necessary for optimization of the actuation system in future work. The system shows comparable work output and has the benefits of biological muscle-like properties for potential use in robotic systems

  4. Identification and characterization of a new Zirconium hydride

    International Nuclear Information System (INIS)

    Zhao, Z.

    2007-01-01

    In order to control the integrity of the fuel clad, alloy of zirconium, it is necessary to predict the behavior of zirconium hydrides in the environment (temperature, stress...), at a microscopic scale. A characterization study by TEM of hydrides has been realized. It shows little hydrides about 500 nm, in hydride Zircaloy 4. Then a more detailed study identified a new hydride phase presented in this paper. (A.L.B.)

  5. Reactivity patterns of transition metal hydrides and alkyls

    International Nuclear Information System (INIS)

    Jones, W.D. II.

    1979-05-01

    The complex PPN + CpV(CO) 3 H - (Cp=eta 5 -C 5 H 5 and PPN = (Ph 3 P) 2 ) was prepared in 70% yield and its physical properties and chemical reactions investigated. PPN + CpV(CO) 3 H - reacts with a wide range of organic halides. The organometallic products of these reactions are the vanadium halides PPN + [CpV(C) 3 X] - and in some cases the binuclear bridging hydride PPN + [CpV(CO) 3 ] 2 H - . The borohydride salt PPN + [CpV(CO) 3 BH 4 ] - has also been prepared. The reaction between CpV(CO) 3 H - and organic halides was investigated and compared with halide reductions carried out using tri-n-butyltin hydride. Results demonstrate that in almost all cases, the reduction reaction proceeds via free radical intermediates which are generated in a chain process, and are trapped by hydrogen transfer from CpV(CO) 3 H - . Sodium amalgam reduction of CpRh(CO) 2 or a mixture of CpRh(CO) 2 and CpCo(CO) 2 affords two new anions, PPN + [Cp 2 Rh 3 (CO) 4 ] - and PPN + [Cp 2 RhCo(CO) 2 ] - . CpMo(CO) 3 H reacts with CpMo(CO) 3 R (R=CH 3 ,C 2 H 5 , CH 2 C 6 H 5 ) at 25 to 50 0 C to produce aldehyde RCHO and the dimers [CpMo(CO) 3 ] 2 and [CpMo(CO) 2 ] 2 . In general, CpV(CO) 3 H - appears to transfer a hydrogen atom to the metal radical anion formed in an electron transfer process, whereas CpMo(CO) 3 H transfers hydride in a 2-electron process to a vacant coordination site. The chemical consequences are that CpV(CO) 3 H - generally reacts with metal alkyls to give alkanes via intermediate alkyl hydride species whereas CpMo(CO) 3 H reacts with metal alkyls to produce aldehyde, via an intermediate acyl hydride species

  6. Reactivity patterns of transition metal hydrides and alkyls

    Energy Technology Data Exchange (ETDEWEB)

    Jones, W.D. II

    1979-05-01

    The complex PPN/sup +/ CpV(CO)/sub 3/H/sup -/ (Cp=eta/sup 5/-C/sub 5/H/sub 5/ and PPN = (Ph/sub 3/P)/sub 2/) was prepared in 70% yield and its physical properties and chemical reactions investigated. PPN/sup +/ CpV(CO)/sub 3/H/sup -/ reacts with a wide range of organic halides. The organometallic products of these reactions are the vanadium halides PPN/sup +/(CpV(C)/sub 3/X)/sup -/ and in some cases the binuclear bridging hydride PPN/sup +/ (CpV(CO)/sub 3/)/sub 2/H/sup -/. The borohydride salt PPN/sup +/(CpV(CO)/sub 3/BH/sub 4/)/sup -/ has also been prepared. The reaction between CpV(CO)/sub 3/H/sup -/ and organic halides was investigated and compared with halide reductions carried out using tri-n-butyltin hydride. Results demonstrate that in almost all cases, the reduction reaction proceeds via free radical intermediates which are generated in a chain process, and are trapped by hydrogen transfer from CpV(CO)/sub 3/H/sup -/. Sodium amalgam reduction of CpRh(CO)/sub 2/ or a mixture of CpRh(CO)/sub 2/ and CpCo(CO)/sub 2/ affords two new anions, PPN/sup +/ (Cp/sub 2/Rh/sub 3/(CO)/sub 4/)/sup -/ and PPN/sup +/(Cp/sub 2/RhCo(CO)/sub 2/)/sup -/. CpMo(CO)/sub 3/H reacts with CpMo(CO)/sub 3/R (R=CH/sub 3/,C/sub 2/H/sub 5/, CH/sub 2/C/sub 6/H/sub 5/) at 25 to 50/sup 0/C to produce aldehyde RCHO and the dimers (CpMo(CO)/sub 3/)/sub 2/ and (CpMo(CO)/sub 2/)/sub 2/. In general, CpV(CO)/sub 3/H/sup -/ appears to transfer a hydrogen atom to the metal radical anion formed in an electron transfer process, whereas CpMo(CO)/sub 3/H transfers hydride in a 2-electron process to a vacant coordination site. The chemical consequences are that CpV(CO)/sub 3/H/sup -/ generally reacts with metal alkyls to give alkanes via intermediate alkyl hydride species whereas CpMo(CO)/sub 3/H reacts with metal alkyls to produce aldehyde, via an intermediate acyl hydride species.

  7. Hydride heat pump with heat regenerator

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    1991-01-01

    A regenerative hydride heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system. A series of at least four canisters containing a lower temperature performing hydride and a series of at least four canisters containing a higher temperature performing hydride is provided. Each canister contains a heat conductive passageway through which a heat transfer fluid is circulated so that sensible heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

  8. A procedure for preparing alkali metal hydrides

    International Nuclear Information System (INIS)

    Lemieux, R.U.; Sanford, C.E.; Prescott, J.F.

    1976-01-01

    A plain low cost, procedure for the continuous, low temperature preparation of sodium or potassium hydrides using cheap reagents is presented. Said invention is especially concerned with a process of purifying of a catalytic exchange liquid used for deuterium enrichment, in which an alkali metal hydride is produced as intermediate product. The procedure for producing the sodium and potassium hydrides consists in causing high pressure hydrogen to be absorbed by a mixture of at least a lower monoalkylamine and an alkylamide of an alkali metal from at least one of said amines [fr

  9. Hydride observations using the neutrography technique

    International Nuclear Information System (INIS)

    Meyer, G.; Baruj, A.; Borzone, E.M.; Cardenas, R.; Szames, E.; Somoza, J.; Rivas, S.; Sanchez, F.A.; Marin, J.

    2012-01-01

    Neutron radiography observations were performed at the RA-6 experimental nuclear facility in Bariloche. Images from a prototype of a hydride-based hydrogen storage device have been obtained. The technique allows visualizing the inner hydride space distribution. The hydride appeared compacted at the lower part of the prototype after several cycles of hydrogen charge and discharge. The technique has also been applied to the study of Zr/ZrH 2 samples. There is a linear relation between the sample width/hydrogen concentration and the photograph grey scale. This information could be useful for the study of nuclear engineering materials and to determine their possible degradation by hydrogen pick up (author)

  10. Decomposition kinetics of plutonium hydride

    Energy Technology Data Exchange (ETDEWEB)

    Haschke, J.M.; Stakebake, J.L.

    1979-01-01

    Kinetic data for decomposition of PuH/sub 1/ /sub 95/ provides insight into a possible mechanism for the hydriding and dehydriding reactions of plutonium. The fact that the rate of the hydriding reaction, K/sub H/, is proportional to P/sup 1/2/ and the rate of the dehydriding process, K/sub D/, is inversely proportional to P/sup 1/2/ suggests that the forward and reverse reactions proceed by opposite paths of the same mechanism. The P/sup 1/2/ dependence of hydrogen solubility in metals is characteristic of the dissociative absorption of hydrogen; i.e., the reactive species is atomic hydrogen. It is reasonable to assume that the rates of the forward and reverse reactions are controlled by the surface concentration of atomic hydrogen, (H/sub s/), that K/sub H/ = c'(H/sub s/), and that K/sub D/ = c/(H/sub s/), where c' and c are proportionality constants. For this surface model, the pressure dependence of K/sub D/ is related to (H/sub s/) by the reaction (H/sub s/) reversible 1/2H/sub 2/(g) and by its equilibrium constant K/sub e/ = (H/sub 2/)/sup 1/2//(H/sub s/). In the pressure range of ideal gas behavior, (H/sub s/) = K/sub e//sup -1/(RT)/sup -1/2/ and the decomposition rate is given by K/sub D/ = cK/sub e/(RT)/sup -1/2/P/sup 1/2/. For an analogous treatment of the hydriding process with this model, it can be readily shown that K/sub H/ = c'K/sub e//sup -1/(RT)/sup -1/2/P/sup 1/2/. The inverse pressure dependence and direct temperature dependence of the decomposition rate are correctly predicted by this mechanism which is most consistent with the observed behavior of the Pu--H system.

  11. The Oxidation Products of Aluminum Hydride and Boron Aluminum Hydride Clusters

    Science.gov (United States)

    2016-01-04

    AFRL-AFOSR-VA-TR-2016-0075 The Oxidation Products of Aluminum Hydride and Boron Aluminum Hydride Clusters KIT BOWEN JOHNS HOPKINS UNIV BALTIMORE MD...2. REPORT TYPE Final Performance 3. DATES COVERED (From - To) 30-09-2014 to 29-09-2015 4. TITLE AND SUBTITLE The Oxidation Products of Aluminum ...Hydride and Boron Aluminum Hydride Clusters 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER FA9550-14-1-0324 5c.  PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S) KIT

  12. Tritium removal using vanadium hydride

    International Nuclear Information System (INIS)

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

    1978-01-01

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

  13. Rotary drum dryers for coal slurries

    Energy Technology Data Exchange (ETDEWEB)

    Baunack, F

    1983-04-01

    The suitability, sizing and internal equipment of rotary drum dryers for high-ash coal slurries are discussed. Rotary dryers will handle also difficult slurries; by suitable drum sizes, lifter blades and chains not only high specific evaporation capacities can be achieved but also very high throughputs of up to 400 tons/h of finished product and high evaporation capacities of 60 tons/h.

  14. Optical and photoemission studies of lanthanum hydrides

    International Nuclear Information System (INIS)

    Peterman, D.J.; Peterson, D.T.; Weaver, J.H.

    1980-01-01

    The results of optical absorptivity and photoemission measurements on lanthanum hydrides, LaH/sub x/ (1.98 less than or equal to x less than or equal to 2.89) are reported. The low energy (hν less than or equal to 0.5 eV) optical features in LaH/sub x/ are attributed to the filling of octahedral sites. Higher energy interband absorption involves states within the d-band complex, analogous to other dihydrides. As x increases above 2.0, the optical features change rapidly due to the increase in the number of occupied octahedral sites. Various band structure studies suggest that LaH 3 might be a semiconductor. Photoemission results show that as x increases, the d-derived states at E/sub F/ are drawn down and that for LaH 2 89 only very weak valence band emission is observed. The hydrogen-derived bonding bands are shown centered approx. 5 eV below E/sub F/. Observed chemical shifts in the La 5p/sub 1/2 3/2/ cores are discussed for 1.98 less than or equal to x less than or equal to 2.89

  15. Improvements of marine clay slurries using chemical–physical combined method (CPCM

    Directory of Open Access Journals (Sweden)

    Dongqing Wu

    2015-04-01

    Full Text Available In this paper, the effectiveness, applicability and validity of chemical–physical combined methods (CPCMs for treatment of marine clay (MC slurries were evaluated. The method CPCM1 combines chemical stabilization and vacuum preloading (VP, while CPCM2 is similar to CPCM1 but includes both the application of surcharge and use of geo-bags to provide confinement during surcharge preloading. The key advantage of CPCM2 using geo-bags is that the surcharge can be immediately applied on the chemically stabilized slurries. Two types of geo-bags were investigated under simulated land filling and dyke conditions, respectively. The test results show that the shear strength (cu of treated slurry by CPCM2 is generally much higher than that by CPCM1. Besides, the use of CPCM2 can significantly reduce the treatment time due to the short drainage paths created by geo-bags. Overall, CPCM2 allows faster consolidation and higher preloading that help to achieve higher mechanical properties of the stabilized slurry. There are consistent relationships between cU and water content of slurries treated by CPCM2. Several important observations were also made based on comparisons of experimental data.

  16. Disposal of tritium-exposed metal hydrides

    International Nuclear Information System (INIS)

    Nobile, A.; Motyka, T.

    1991-01-01

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

  17. Method of making alkali metal hydrides

    Science.gov (United States)

    Pecharsky, Vitalij K.; Gupta, Shalabh; Pruski, Marek; Hlova, Ihor; Castle, Andra

    2017-05-30

    A method is provided for making alkali metal hydrides by mechanochemically reacting alkali metal and hydrogen gas under mild temperature (e.g room temperature) and hydrogen pressure conditions without the need for catalyst, solvent, and intentional heating or cooling.

  18. Fullerene hydride - A potential hydrogen storage material

    International Nuclear Information System (INIS)

    Nai Xing Wang; Jun Ping Zhang; An Guang Yu; Yun Xu Yang; Wu Wei Wang; Rui long Sheng; Jia Zhao

    2005-01-01

    Hydrogen, as a clean, convenient, versatile fuel source, is considered to be an ideal energy carrier in the foreseeable future. Hydrogen storage must be solved in using of hydrogen energy. To date, much effort has been put into storage of hydrogen including physical storage via compression or liquefaction, chemical storage in hydrogen carriers, metal hydrides and gas-on-solid adsorption. But no one satisfies all of the efficiency, size, weight, cost and safety requirements for transportation or utility use. C 60 H 36 , firstly synthesized by the method of the Birch reduction, was loaded with 4.8 wt% hydrogen indicating [60]fullerene might be as a potential hydrogen storage material. If a 100% conversion of C 60 H 36 is achieved, 18 moles of H 2 gas would be liberated from each mole of fullerene hydride. Pure C 60 H 36 is very stable below 500 C under nitrogen atmosphere and it releases hydrogen accompanying by other hydrocarbons under high temperature. But C 60 H 36 can be decomposed to generate H 2 under effective catalyst. We have reported that hydrogen can be produced catalytically from C 60 H 36 by Vasks's compound (IrCl(CO)(PPh 3 ) 2 ) under mild conditions. (RhCl(CO)(PPh 3 ) 2 ) having similar structure to (IrCl(CO)(PPh 3 ) 2 ), was also examined for thermal dehydrogenation of C 60 H 36 ; but it showed low catalytic activity. To search better catalyst, palladium carbon (Pd/C) and platinum carbon (Pt/C) catalysts, which were known for catalytic hydrogenation of aromatic compounds, were tried and good results were obtained. A very big peak of hydrogen appeared at δ=5.2 ppm in 1 H NMR spectrum based on Evans'work (fig 1) at 100 C over a Pd/C catalyst for 16 hours. It is shown that hydrogen can be produced from C 60 H 36 using a catalytic amount of Pd/C. Comparing with Pd/C, Pt/C catalyst showed lower activity. The high cost and limited availability of Vaska's compounds, Pd and Pt make it advantageous to develop less expensive catalysts for our process based on

  19. The differences between soil grouting with cement slurry and cement-water glass slurry

    Science.gov (United States)

    Zhu, Mingting; Sui, Haitong; Yang, Honglu

    2018-01-01

    Cement slurry and cement-water glass slurry are the most widely applied for soil grouting reinforcement project. The viscosity change of cement slurry is negligible during grouting period and presumed to be time-independent while the viscosity of cement-water glass slurry increases with time quickly and is presumed to be time-dependent. Due to the significantly rheology differences between them, the grouting quality and the increasing characteristics of grouting parameters may be different, such as grouting pressure, grouting surrounding rock pressure, i.e., the change of surrounding rock pressure deduced by grouting pressure. Those are main factors for grouting design. In this paper, a large-scale 3D grouting simulation device was developed to simulate the surrounding curtain grouting for a tunnel. Two series of surrounding curtain grouting experiments under different geo-stress of 100 kPa, 150 kPa and 200 kPa were performed. The overload test on tunnel was performed to evaluate grouting effect of all surrounding curtain grouting experiments. In the present results, before 240 seconds, the grouting pressure increases slowly for both slurries; after 240 seconds the increase rate of grouting pressure for cement-water glass slurry increases quickly while that for cement slurry remains roughly constant. The increasing trend of grouting pressure for cement-water glass is similar to its viscosity. The setting time of cement-water glass slurry obtained from laboratory test is less than that in practical grouting where grout slurry solidifies in soil. The grouting effect of cement-water glass slurry is better than that of cement slurry and the grouting quality decreases with initial pressure.

  20. Utilization technology on slurried ash

    Energy Technology Data Exchange (ETDEWEB)

    Kanbe, Yoshio; Yasuda, Minoru; Furuki, Yasuhiko [The Coal Mining Research Centre, Japan, Tokyo, Japan; Electric Power Development Co., Ltd., Tokyo (Japan))

    1987-08-01

    Three research results of the utilization technology on slurried ash were reported. As for the utilization as the fly ash quick setting (FQS) backfill grout for tail void in shield works of tunneling, grout blending was simplified, the blended solution of cement, clay, additives and water was stabilized, and a favorable workability and long term durability were obtained. As for the utilization as the material of a SMW (soil mixing wall) method for continuous walls in long shaft digging, a fly ash-gypsum-cement (FGC) stabilizer showed an excellent workability and remarkably high water-tightness as compared with conventional cement bentonite. As for the utilization as the material of an injection method of overlay mats in foundation works of light weight structures on the sea bed mud foundation, since a FGC concrete weight in water was remarkably light as 0.7t/m{sup 3}, no both large mold form strength and vibration compacting were required. 10 figs., 8 tabs.

  1. Influence of hydrides orientation on strain, damage and failure of hydrided zircaloy-4

    International Nuclear Information System (INIS)

    Racine, A.

    2005-09-01

    In pressurized water reactors of nuclear power plants, fuel pellets are contained in cladding tubes, made of Zirconium alloy, for instance Zircaloy-4. During their life in the primary water of the reactor (155 bars, 300 C), cladding tubes are oxidized and consequently hydrided. A part of the hydrogen given off precipitates as Zirconium hydrides in the bulk material and embrittles the material. This embrittlement depends on many parameters, among which hydrogen content and orientation of hydrides with respect to the applied stress. This investigation is devoted to the influence of the orientation of hydrides with respect to the applied stress on strain, damage and failure mechanisms. Macroscopic and SEM in-situ ring tensile tests are performed on cladding tube material (unirradiated cold worked stress-relieved Zircaloy-4) hydrided with about 200 and 500 wppm hydrogen, and with different main hydrides orientation: either parallel or perpendicular to the circumferential tensile direction. We get the mechanical response of the material as a function of hydride orientation and hydrogen content and we investigate the deformation, damage and failure mechanisms. In both cases, digital image correlation techniques are used to estimate local and global strain distributions. Neither the tensile stress-strain response nor the global and local strain modes are significantly affected by hydrogen content or hydride orientation, but the failure modes are strongly modified. Indeed, only 200 wppm radial hydrides embrittle Zy-4: sample fail in the elastic domain at about 350 MPa before strain bands could develop; whereas in other cases sample reach at least 750 MPa before necking and final failure, in ductile or brittle mode. To model this particular heterogeneous material behavior, a non-coupled damage approach which takes into account the anisotropic distribution of the hydrides is proposed. Its parameters are identified from the macroscopic strain field measurements and a

  2. Studies of coal slurries property; Slurry no seijo ni kansuru kento

    Energy Technology Data Exchange (ETDEWEB)

    Kawabata, M.; Aihara, Y.; Imada, K. [Nippon Steel Corp., Tokyo (Japan); Nogami, Y.; Inokuchi, K. [Mitsui SRC Development Co. Ltd., Tokyo (Japan); Sakaki, T.; Shibata, M.; Hirosue, H. [Kyushu National Industrial Research Institute, Saga (Japan)

    1996-10-28

    It was previously found that the increase of slurry temperature provides a significant effect of slurry viscosity reduction for the coal slurry with high concentration of 50 wt%. To investigate the detailed influence of slurry temperature for the coal slurry with concentration of 50 wt%, influence of temperature on the successive change of apparent viscosity was observed at the constant shear rate. When the concentration of coal was increased from 45 wt% to 50 wt%, viscosity of the slurry was rapidly increased. When heated above 70{degree}C, the apparent viscosity decreased during heating to the given temperature, but it increased successively after reaching to the given temperature. The apparent viscosity showed higher value than that of the initial viscosity. The coal slurry with concentration of 50 wt% showed the fluidity of Newtonian fluid at the lower shear rate region, but showed the fluidity of pseudo-plastic fluid at the higher shear rate region. The slurry having high apparent viscosity by the successive change showed higher apparent viscosity with increasing the higher even by changing the shear rate. 1 ref., 4 figs.

  3. Conductivity and electrochemical performance of LiFePO4 slurry in the lithium slurry battery

    Science.gov (United States)

    Feng, Caimei; Chen, Yongchong; Liu, Dandan; Zhang, Ping

    2017-06-01

    Lithium slurry battery is a new type of energy storage technique which uses the slurry of solid active materials, conductive additions and liquid electrolyte as the electrode. The proportion of conductive addition and the active material has significant influence on the conductivity and electrochemical performance of the slurry electrode. In the present work, slurries with different volume ratios of LiFePO4 (LFP) and Ketjenblack (KB) were investigated by the electrochemical workstation and charge-discharge testing system (vs. Li/Li+). Results show that the conductivity of the slurry increases linearly with the addition of KB, and the measured specific capacity of the slurry reaches its theoretical value when the volume ratio of KB to LFP is around 0.2. Based on this ratio, a slurry battery with higher loading of LFP (19.1 wt.% in the slurry) was tested, and a specific capacity of 165 mAh/g at 0.2 mA/cm2 and 102 mAh/g at 5 mA/cm2 was obtained for LFP.

  4. Conceptual study on HTGR-IS hydrogen supply system using organic hydrides

    International Nuclear Information System (INIS)

    Terada, Atsuhiko; Noguchi, Hiroki; Takegami, Hiroaki; Kamiji, Yu; Inagaki, Yoshiyuki

    2012-02-01

    We have proposed a hydrogen supply-chain system, which is a storage/supply system of large amount of hydrogen produced by HTGR-IS hydrogen production system. The organic chemical hydride method is one of the candidate techniques in the system for hydrogen storage and transportation. In this study, properties of organic hydrides and conventional hydrogen storage/supply system were surveyed to make use of the conceptual design of the hydrogen supply system using an organic hydrides method with VHTR-IS hydrogen production process (hydrogen production: 85,400 Nm 3 /h). Conceptual specifications of the main equipments were designed for the hydrogen supply system consisting of hydrogenation and dehydrogenation process. It was also clarified the problems of hydrogen supply system, such as energy efficiency and system optimization. (author)

  5. Manufacturing and investigation of U-Mo LEU fuel granules by hydride-dehydride processing

    International Nuclear Information System (INIS)

    Stetskiy, Y.A.; Trifonov, Y.I.; Mitrofanov, A.V.; Samarin, V.I.

    2002-01-01

    Investigations of hydride-dehydride processing for comminution of U-Mo alloys with Mo content in the range 1.9/9.2% have been performed. Some regularities of the process as a function of Mo content have been determined as well as some parameters elaborated. Hydride-dehydride processing has been shown to provide necessary phase and chemical compositions of U-Mo fuel granules to be used in disperse fuel elements for research reactors. Pin type disperse mini-fuel elements for irradiation tests in the loop of 'MIR' reactor (Dmitrovgrad) have been fabricated using U-Mo LEU fuel granules obtained by hydride-dehydride processing. Irradiation tests of these mini-fuel elements loaded to 4 g U tot /cm 3 are planned to start by the end of this year. (author)

  6. Soil microbial properties after long-term swine slurry application to conventional and no-tillage systems in Brazil.

    Science.gov (United States)

    Balota, Elcio L; Machineski, Oswaldo; Hamid, Karima I A; Yada, Ines F U; Barbosa, Graziela M C; Nakatani, Andre S; Coyne, Mark S

    2014-08-15

    Swine waste can be used as an agricultural fertilizer, but large amounts may accumulate excess nutrients in soil or contaminate the surrounding environment. This study evaluated long-term soil amendment (15 years) with different levels of swine slurry to conventional (plow) tillage (CT) and no tillage (NT) soils. Long-term swine slurry application did not affect soil organic carbon. Some chemical properties, such as calcium, base saturation, and aluminum saturation were significantly different within and between tillages for various application rates. Available P and microbial parameters were significantly affected by slurry addition. Depending on tillage, soil microbial biomass and enzyme activity increased up to 120 m(3) ha(-1) year(-1) in all application rates. The NT system had higher microbial biomass and activity than CT at all application levels. There was an inverse relationship between the metabolic quotient (qCO2) and MBC, and the qCO2 was 53% lower in NT than CT. Swine slurry increased overall acid phosphatase activity, but the phosphatase produced per unit of microbial biomass decreased. A comparison of data obtained in the 3rd and 15th years of swine slurry application indicated that despite slurry application the CT system degraded with time while the NT system had improved values of soil quality indicators. For these Brazilian oxisols, swine slurry amendment was insufficient to maintain soil quality parameters in annual crop production without additional changes in tillage management. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. gamma-Zr-Hydride Precipitate in Irradiated Massive delta- Zr-Hydride

    DEFF Research Database (Denmark)

    Warren, M. R.; Bhattacharya, D. K.

    1975-01-01

    During examination of A Zircaloy-2-clad fuel pin, which had been part of a test fuel assembly in a boiling water reactor, several regions of severe internal hydriding were noticed in the upper-plenum end of the pin. Examination of similar fuel pins has shown that hydride of this type is caused by...... to irradiation-induced swelling....

  8. CEMENT SLURRIES FOR GEOTHERMAL WELLS CEMENTING

    Directory of Open Access Journals (Sweden)

    Nediljka Gaurina-Međimurec

    1994-12-01

    Full Text Available During a well cementing special place belongs to the cement slurry design. To ensure the best quality of cementing, a thorough understanding of well parameters is essential, as well as behaviour of cement slurry (especially at high temperatures and application of proven cementing techniques. Many cement jobs fail because of bad job planning. Well cementing without regarding what should be accomplished, can lead to well problems (channels in the cement, unwanted water, gas or fluid production, pipe corrosion and expensive well repairs. Cementing temperature conditions are important because bot-tomhole circulating temperatures affect slurry thickening time, arheology, set time and compressive strength development. Knowing the actual temperature which cement encounters during placement allows the selection of proper cementing materials for a specific application. Slurry design is affected by well depth, bottom hole circulating temperature and static temperature, type or drilling fluid, slurry density, pumping time, quality of mix water, fluid loss control, flow regime, settling and free water, quality of cement, dry or liquid additives, strength development, and quality of the lab cement testing and equipment. Most Portland cements and Class J cement have shown suitable performances in geot-hermal wells. Cement system designs for geothermal wells differ from those for conventional high temperature oil and gas wells in the exclusive use of silica flour instead of silica sand, and the avoidance of fly ash as an extender. In this paper, Portland cement behaviour at high temperatures is described. Cement slurry and set cement properties are also described. Published in literature, the composition of cement slurries which were tested in geothermal conditions and which obtained required compressive strength and water permeability are listed. As a case of our practice geothermal wells Velika Ciglena-1 and Velika Ciglena-la are described.

  9. Rheology of Colombian coal-water slurry fuels: Effect of particle-size distribution

    Energy Technology Data Exchange (ETDEWEB)

    Pulido, J E; Rojas, C P; Acero, G [Universidad Industrial de Santander, Bucaramanga (Colombia)

    1996-12-31

    Coal-water slurry fuels (CWSF`s) have been prepared and characterized in a research project in Colombia, sponsored by Colciencias and Ecocarbon, in order to evaluate the effects of the different composition variables on the behavior during preparation and pipe line transportation. The authors have previously presented details describing the characteristics of the slurry fuels prepared with five types of Colombian thermal coals and the influence of their chemical composition on the optimum particle-size distribution (PSD) required to prepare highly loaded and workable CWSF`s. The formulation and design of flow systems of suspensions with high solids content, such as the CWSF`s, require a detailed rheological knowledge of the suspension in terms of the governing parameters related to PSD, coal content, surface chemistry of the particles and dispersants used to stabilize the slurries. Important studies on these aspects have been reviewed and carried out experimentally by other authors specially devoted to the correlations between apparent viscosity, solids content and average coal particle-size. One of the targets to obtain an optimum control on the viscosity and flow properties of the CWSF`s must be based in correlating the Theological constants for the prevailing model of viscosity law to the characteristic parameters of the particle-size distribution and to the coal content in the slurry. In spite of the effect of PSD on the rheology of highly-loaded coal slurries have been long recognized as significant, the specific influence of the various PSD`s on the parameters of the Theological model continues to receive attention to further understanding in order to improve the slurry formulations for a specified purpose on preparation and hydraulic handling. This paper reports the results of an experimental technique of examining the various PSD`s on coal slurry fuel rheology, taking special attention for the effect on the parameters of the rheological model.

  10. Hydrodynamics and mass transfer in slurry bubble columns : scale and pressure effects

    NARCIS (Netherlands)

    Chilekar, V.P.

    2007-01-01

    Slurry bubble columns (SBC) are widely used in the chemical industry as a multiphase reactor. Applications include oxidation and hydrogenation reactions, fermentation, Fischer-Tropsch synthesis, and waste water treatment. The advantages of a SBC over other multiphase reactors are the simple

  11. The Effect of Hydrogen and Hydrides on the Integrity of Zirconium Alloy Components Delayed Hydride Cracking

    CERN Document Server

    Puls, Manfred P

    2012-01-01

    By drawing together the current theoretical and experimental understanding of the phenomena of delayed hydride cracking (DHC) in zirconium alloys, The Effect of Hydrogen and Hydrides on the Integrity of Zirconium Alloy Components: Delayed Hydride Cracking provides a detailed explanation focusing on the properties of hydrogen and hydrides in these alloys. Whilst the focus lies on zirconium alloys, the combination of both the empirical and mechanistic approaches creates a solid understanding that can also be applied to other hydride forming metals.   This up-to-date reference focuses on documented research surrounding DHC, including current methodologies for design and assessment of the results of periodic in-service inspections of pressure tubes in nuclear reactors. Emphasis is placed on showing that our understanding of DHC is supported by progress across a broad range of fields. These include hysteresis associated with first-order phase transformations; phase relationships in coherent crystalline metallic...

  12. Slurry feed variability in West Valley's melter feed tank and sampling system

    International Nuclear Information System (INIS)

    Fow, C.L.; Kurath, D.E.; Pulsipher, B.A.; Bauer, B.P.

    1989-04-01

    The present plan for disposal of high-level wastes at West Valley is to vitrify the wastes for disposal in deep geologic repository. The vitrification process involves mixing the high-level wastes with glass-forming chemicals and feeding the resulting slurry to a liquid-fed ceramic melter. Maintaining the quality of the glass product and proficient melter operation depends on the ability of the melter feed system to produce and maintain a homogeneous mixture of waste and glass-former materials. To investigate the mixing properties of the melter feed preparation system at West Valley, a statistically designed experiment was conducted using synthetic melter feed slurry over a range of concentrations. On the basis of the statistical data analysis, it was found that (1) a homogeneous slurry is produced in the melter feed tank, (2) the liquid-sampling system provides slurry samples that are statistically different from the slurry in the tank, and (3) analytical measurements are the major source of variability. A statistical quality control program for the analytical laboratory and a characterization test of the actual sampling system is recommended. 1 ref., 5 figs., 1 tab

  13. EVALUATION OF MIXING IN THE SLURRY MIX EVAPORATOR AND MELTER FEED TANK

    International Nuclear Information System (INIS)

    MARINIK, ANDREW

    2004-01-01

    The Defense Waste Processing Facility (DWPF) vitrifies High Level radioactive Waste (HLW) currently stored in underground tanks at the Savannah River Site (SRS). The HLW currently being processed is a waste sludge composed primarily of metal hydroxides and oxides in caustic slurry. These slurries are typically characterized as Bingham Plastic fluids. The HLW undergoes a pretreatment process in the Chemical Process Cell (CPC) at DWPF. The processed HLW sludge is then transferred to the Sludge Receipt and Adjustment Tank (SRAT) where it is acidified with nitric and formic acid then evaporated to concentrate the solids. Reflux boiling is used to strip mercury from the waste and then the waste is transferred to the Slurry Mix Evaporator tank (SME). Glass formers are added as a frit slurry to the SME to prepare the waste for vitrification. This mixture is evaporated in the SME to the final concentration target. The frit slurry mixture is then transferred to the Melter Feed Tank (MFT) to be fed to the melter

  14. Achievement report for 1st phase (fiscal 1974-80) Sunshine Program research and development - Hydrogen energy. Research on transportation of hydrogen in the form of metallic hydride; 1974-1980 nendo kinzoku suisokabutsu ni yoru suiso no yuso gijutsu no kenkyu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-03-01

    This report concerns the transportation and storage of hydrogen using metallic hydrides that perform absorption and desorption of hydrogen. Alloys useable for this purpose have to be capable of reversibly absorbing and desorbing hydrogen within a certain temperature range. In the absence of guidelines to follow in the quest for such alloys, the efforts at discovering them turned out to be a continual series of trials and errors. Researches were conducted into the hydrogenation reaction of Mg and Mg-based alloys and into hydrides of V-based alloys, and into Zr-based alloy hydrides such as the ZrMn{sub 2} hydride, ZrNiMn hydride, Zr(Fe{sub x}Mn{sub 1-x}){sub 2} hydrides, TiZrFe{sub 2} hydride, Zr{sub x}Ti{sub 1-x}(Fe{sub y}Mn{sub 1-y}) hydrides, etc. Also studied were the electronics of hydrogen in metallic hydrides, rates of reaction between Mg-Ni-based alloys and hydrogen systems, endurance tests for hydrides of Mg-Ni-based alloys, effects exerted by absorbed gas molecules during the storage of hydrogen in Mg-Ni-based alloys, effective thermal conductivity in a layer filled with a metallic hydride, metallic hydride-aided hydrogen transportation systems, chemical boosters, etc. (NEDO)

  15. Origin of high oxide to nitride polishing selectivity of ceria-based slurry in the presence of picolinic acid

    International Nuclear Information System (INIS)

    Wang Liang-Yong; Liu Bo; Song Zhi-Tang; Liu Wei-Li; Feng Song-Lin; David Huang; Babu, S.V

    2011-01-01

    We report on the investigation of the origin of high oxide to nitride polishing selectivity of ceria-based slurry in the presence of picolinic acid. The oxide to nitride removal selectivity of the ceria slurry with picolinic acid is as high as 76.6 in the chemical mechanical polishing. By using zeta potential analyzer, particle size analyzer, horizon profilometer, thermogravimetric analysis and Fourier transform infrared spectroscopy, the pre- and the post-polished wafer surfaces as well as the pre- and the post-used ceria-based slurries are compared. Possible mechanism of high oxide to nitride selectivity with using ceria-based slurry with picolinic acid is discussed. (interdisciplinary physics and related areas of science and technology)

  16. Origin of high oxide to nitride polishing selectivity of ceria-based slurry in the presence of picolinic acid

    Institute of Scientific and Technical Information of China (English)

    Wang Liang-Yong; Liu Bo; Song Zhi-Tang; Liu Wei-Li; Feng Song-Lin; David Huang; S.V Babu

    2011-01-01

    We report on the investigation of the origin of high oxide to nitride polishing selectivity of ceria-based slurry in the presence of picolinic acid. The oxide to nitride removal selectivity of the ceria slurry with picolinic acid is as high as 76.6 in the chemical mechanical polishing. By using zeta potential analyzer, particle size analyzer, horizon profilometer, thermogravimetric analysis and Fourier transform infrared spectroscopy, the pre-and the post-polished wafer surfaces as well as the pre-and the post-used ceria-based slurries are compared. Possible mechanism of high oxide to nitride selectivity with using ceria-based slurry with picolinic acid is discussed.

  17. Synthesis of Nano-Light Magnesium Hydride for Hydrogen Storage ...

    African Journals Online (AJOL)

    Abstract. Nano-light magnesium hydride that has the capability for hydrogen storage was synthesized from treatment of magnesium ribbon with hydrogen peroxide. The optimum time for complete hydrogenation of the magnesium hydride was 5 hours.

  18. High H⁻ ionic conductivity in barium hydride.

    Science.gov (United States)

    Verbraeken, Maarten C; Cheung, Chaksum; Suard, Emmanuelle; Irvine, John T S

    2015-01-01

    With hydrogen being seen as a key renewable energy vector, the search for materials exhibiting fast hydrogen transport becomes ever more important. Not only do hydrogen storage materials require high mobility of hydrogen in the solid state, but the efficiency of electrochemical devices is also largely determined by fast ionic transport. Although the heavy alkaline-earth hydrides are of limited interest for their hydrogen storage potential, owing to low gravimetric densities, their ionic nature may prove useful in new electrochemical applications, especially as an ionically conducting electrolyte material. Here we show that barium hydride shows fast pure ionic transport of hydride ions (H(-)) in the high-temperature, high-symmetry phase. Although some conductivity studies have been reported on related materials previously, the nature of the charge carriers has not been determined. BaH2 gives rise to hydride ion conductivity of 0.2 S cm(-1) at 630 °C. This is an order of magnitude larger than that of state-of-the-art proton-conducting perovskites or oxide ion conductors at this temperature. These results suggest that the alkaline-earth hydrides form an important new family of materials, with potential use in a number of applications, such as separation membranes, electrochemical reactors and so on.

  19. Economic analysis of hydride fueled BWR

    International Nuclear Information System (INIS)

    Ganda, F.; Shuffler, C.; Greenspan, E.; Todreas, N.

    2009-01-01

    The economic implications of designing BWR cores with hydride fuels instead of conventional oxide fuels are analyzed. The economic analysis methodology adopted is based on the lifetime levelized cost of electricity (COE). Bracketing values (1970 and 3010 $/kWe) are used for the overnight construction costs and for the power scaling factors (0.4 and 0.8) that correlate between a change in the capital cost to a change in the power level. It is concluded that a newly constructed BWR reactor could substantially benefit from the use of 10 x 10 hydride fuel bundles instead of 10 x 10 oxide fuel bundles design presently in use. The cost saving would depend on the core pressure drop constraint that can be implemented in newly constructed BWRs - it is between 2% and 3% for a core pressure drop constraint as of the reference BWR, between 9% and 15% for a 50% higher core pressure drop, and between 12% and 21% higher for close to 100% core pressure. The attainable cost reduction was found insensitive to the specific construction cost but strongly dependent on the power scaling factor. The cost advantage of hydride fuelled cores as compared to that of the oxide reference core depends only weakly on the uranium and SWU prices, on the 'per volume base' fabrication cost of hydride fuels, and on the discount rate used. To be economically competitive, the uranium enrichment required for the hydride fuelled core needs to be around 10%.

  20. Heavy cement slurries; Pastas pesadas de cimento

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Francisco Avelar da; Conceicao, Antonio C. Farias [PETROBRAS, XX (Brazil). Distrito de Perfuracao do Nordeste. Div. de Tecnicas de Perfuracao; Marins, Carlos Cesar Silva [PETROBRAS, XX (Brazil). Dept. de Perfuracao. Div. de Revestimento e Cimentacao

    1990-12-31

    When going deeper in a high pressure well, the only way to successfully cement your casing or linear is through the use of heavy cement slurry. In 1987 PETROBRAS geologists presented to the Drilling Department a series of deep, hot and high pressure wells to be drilled. The Casing and Cement Division of this department then started a program to face this new challenge. This paper introduces the first part of this program and shows how PETROBRAS is dealing with heavy weight slurries. We present the slurry formulations tested in laboratory, the difficulties found in mixing them in the field, rheology measurements, API free water and API fluid loss from both laboratory and field samples. (author) 3 tabs.

  1. Effect of Particle Size Distribution on Slurry Rheology: Nuclear Waste Simulant Slurries

    International Nuclear Information System (INIS)

    Chun, Jaehun; Oh, Takkeun; Luna, Maria L.; Schweiger, Michael J.

    2011-01-01

    Controlling the rheological properties of slurries has been of great interest in various industries such as cosmetics, ceramic processing, and nuclear waste treatment. Many physicochemical parameters, such as particle size, pH, ionic strength, and mass/volume fraction of particles, can influence the rheological properties of slurry. Among such parameters, the particle size distribution of slurry would be especially important for nuclear waste treatment because most nuclear waste slurries show a broad particle size distribution. We studied the rheological properties of several different low activity waste nuclear simulant slurries having different particle size distributions under high salt and high pH conditions. Using rheological and particle size analysis, it was found that the percentage of colloid-sized particles in slurry appears to be a key factor for rheological characteristics and the efficiency of rheological modifiers. This behavior was shown to be coupled with an existing electrostatic interaction between particles under a low salt concentration. Our study suggests that one may need to implement the particle size distribution as a critical factor to understand and control rheological properties in nuclear waste treatment plants, such as the U.S. Department of Energy's Hanford and Savannah River sites, because the particle size distributions significantly vary over different types of nuclear waste slurries.

  2. Boron-nitrogen based hydrides and reactive composites for hydrogen storage

    DEFF Research Database (Denmark)

    Jepsen, Lars H.; Ley, Morten B.; Lee, Young-Su

    2014-01-01

    Hydrogen forms chemical compounds with most other elements and forms a variety of different chemical bonds. This fascinating chemistry of hydrogen has continuously provided new materials and composites with new prospects for rational design and the tailoring of properties. This review highlights...... a range of new boron and nitrogen based hydrides and illustrates how hydrogen release and uptake properties can be improved. © 2014 Elsevier Ltd....

  3. High Density Hydrogen Storage in Metal Hydride Composites with Air Cooling

    OpenAIRE

    Dieterich, Mila; Bürger, Inga; Linder, Marc

    2015-01-01

    INTRODUCTION In order to combine fluctuating renewable energy sources with the actual demand of electrical energy, storages are essential. The surplus energy can be stored as hydrogen to be used either for mobile use, chemical synthesis or reconversion when needed. One possibility to store the hydrogen gas at high volumetric densities, moderate temperatures and low pressures is based on a chemical reaction with metal hydrides. Such storages must be able to absorb and desorb the hydrogen qu...

  4. Improving profitability through slurry management: a look at the impact of slurry pH on various glass types

    Science.gov (United States)

    Hooper, Abigail R.; Boffa, Christopher C.; Sarkas, Harry W.; Cureton, Kevin

    2015-08-01

    When building an optical system, optical fabricators and designers meticulously choose the glass types for their application knowing that each one will have different chemical, thermal and mechanical properties. As the requirements for new optical systems have grown more demanding, the range of available glass types has vastly expanded and the specifications on the produced products have grown tighter. In an attempt to simplify processes and streamline consumable purchases, optical polishing houses often rely on one polishing slurry to manage these vast array of glass types. An unforeseen consequence of these practices can be a reduction in productivity by reduced removal rate, poor yields and frequent rework all translating into higher costs and reduced profitability. In this paper, the authors will examine the impact slurry pH has on glass types of different compositions and chemical, thermal and mechanical properties when using a double-sided polishing process. Experiments will use material removal rate, surface quality, and surface figure to provide insight into improving process control for differing glass types. Further guidance will be provided on how simple on-site monitoring and adjustment can deliver improved profitability on challenging substrates.

  5. Experimental investigation of strain, damage and failure of hydrided zircaloy-4 with various hydride orientations

    International Nuclear Information System (INIS)

    Racine, A; Catherine, C.S.; Cappelaere, C.; Bornert, M.; Caldemaison, D.

    2005-01-01

    This experimental investigation is devoted to the influence of the orientation of hydrides on the mechanical response of Zircaloy-4. Ring tensile tests are performed on unirradiated CWSR Zircaloy-4, charged with about 200 or 500wppm hydrogen. Hydrides are oriented either parallel ('tangential'), or perpendicular ('radial') to the circumferential tensile direction. Tangential hydrides are usually observed in cladding tubes, however, hydrides can be reoriented after cooling under stress to become radial and then trigger brittle behavior. In this investigation, we perform, 'macroscopic' or SEM in-situ tensile tests on smooth rings, at room temperature. We get the mechanical response of the material as a function of hydride orientation and hydrogen content and we investigate the deformation, damage and failure mechanisms. In both cases, digital image correlation techniques are used to estimate local and global strain distributions. The results lead to the following conclusions: neither the tensile stress-strain response nor the strain modes are affected by hydrogen content or hydride orientation, but the failure modes are. Indeed, only 200wppm radial hydrides embrittle Zy-4: sample fails in the elastic domain at about 350 MPa before strain bands could develop; whereas in other cases samples reach at least 750 MPa before failure, with ductile or brittle mode. (authors)

  6. Study on the degradation of chitosan slurries

    Directory of Open Access Journals (Sweden)

    Benjamin Martini

    2016-01-01

    Full Text Available In the present work, we measured the degradation rate of different chitosan slurries. Several parameters were monitored such as temperature (25 °C, 37 °C, 50 °C; chitosan concentration (1% and 2% (w/V; and polymer molecular weight. The samples were tested in dynamic sweep test mode. This test is able to provide a reliable estimation of viscosity variations of the slurries; in turn, these variations could be related to degradation rate of the system in the considered conditions. The resulting information is particularly important especially in applications in which there is a close relationship between physical properties and molecular structure.

  7. Prospects for coal slurry pipelines in California

    Science.gov (United States)

    Lynch, J. F.

    1978-01-01

    The coal slurry pipeline segment of the transport industry is emerging in the United States. If accepted it will play a vital role in meeting America's urgent energy requirements without public subsidy, tax relief, or federal grants. It is proven technology, ideally suited for transport of an abundant energy resource over thousands of miles to energy short industrial centers and at more than competitive costs. Briefly discussed are the following: (1) history of pipelines; (2) California market potential; (3) slurry technology; (4) environmental benefits; (5) market competition; and (6) a proposed pipeline.

  8. Fast, quantitative, and nondestructive evaluation of hydrided LWR fuel cladding by small angle incoherent neutron scattering of hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Y.; Qian, S.; Littrell, K.; Parish, C.M. [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Plummer, L.K. [University of Oregon, Eugene, OR 97403 (United States)

    2015-05-15

    A nondestructive neutron scattering method to precisely measure the uptake of hydrogen and the distribution of hydride precipitates in light water reactor (LWR) fuel cladding was developed. Zircaloy-4 cladding used in commercial LWRs was used to produce hydrided specimens. The hydriding apparatus consists of a closed stainless-steel vessel that contains Zr alloy specimens and hydrogen gas. Following hydrogen charging, the hydrogen content of the hydrided specimens was measured using the vacuum hot extraction method, by which the samples with desired hydrogen concentrations were selected for the neutron study. Optical microscopy shows that our hydriding procedure results in uniform distribution of circumferential hydrides across the wall thickness. Small angle neutron incoherent scattering was performed in the High Flux Isotope Reactor at Oak Ridge National Laboratory. Our study demonstrates that the hydrogen in commercial Zircaloy-4 cladding can be measured very accurately in minutes by this nondestructive method over a wide range of hydrogen concentrations from a very small amount (≈20 ppm) to over 1000 ppm. The hydrogen distribution in a tube sample was obtained by scaling the neutron scattering rate with a factor determined by a calibration process using standard, destructive direct chemical analysis methods on the specimens. This scale factor can be used in future tests with unknown hydrogen concentrations, thus providing a nondestructive method for determining absolute hydrogen concentrations.

  9. Hydrogen storage in complex hydrides

    International Nuclear Information System (INIS)

    Lupu, D.; Biris, A. R.; Misan, I.

    2005-01-01

    Full text: Hydrogen storage is a key enabling technology for the advancement of hydrogen and fuel cell power technologies in mobile and stationary applications. A relevant role of the fuel cell powered vehicles on the market of the transportation systems will be achieved only if the research and development of on-board vehicular hydrogen storage are able to allow a driving range of at least 500 km. The on-board hydrogen storage systems are more challenging due to the space, weight and cost limitations. This range of autonomy between refueling requires materials able to store at least 6.5% weight hydrogen, available at moderate pressures, at the working temperature of the fuel cells and with acceptable cycling stability. The intensive research on the hydrogen storage in alloys and intermetallic of the LaNi 5 , FeTi or Laves phase type compounds, which started more than three decades ago did not resulted in materials of more than about 3% H storage capacities. The 7.5% H content of the Mg hydride is still of attracting interest but though the absorption has been achieved at lower temperatures by ball milling magnesium with various amounts of nickel, the desorption can not be attained at 1 bar H 2 below 280 deg. C and the kinetics of the process is too slow. In the last decade, the attention is focused on another class of compounds, the complex hydrides of aluminum with alkali metals (alanates), due to their high hydrogen content. It was found that doping with Ti-based catalysts improve the hydrogenation/dehydrogenation conditions of NaAlH 4 . Later on, it was shown that ball milling with solid state catalysts greatly improve the hydrogen desorption kinetics of NaAlH 4 , and this also helps to the rehydriding process. The hydrogen desorption from NaAlH 4 occurs in three steps, it shows a reversible storage capacity of 5.5% H and this led to further research work for a better knowledge of its application relating properties. In this work, ball milling experiments on Na

  10. The growth of crystals of erbium hydride

    International Nuclear Information System (INIS)

    Grimshaw, J.A.; Spooner, F.J.; Wilson, C.G.; McQuillan, A.D.

    1981-01-01

    Crystals of the rare-earth hydride ErH 2 have been produced with face areas greater than a square millimetre and corresponding volumes exceeding those of earlier crystals by orders of magnitude. The hydride, which was produced in bulk polycrystalline form by hydriding erbium metal at 950 0 C, has been examined by optical and X-ray techniques. For material of composition ErH 2 and ErHsub(1.8) the size of the grains and their degree of strain appears to depend more on oxygen contamination during formation and on the subsequent cooling procedure, than on the size of erbium metal crystals in the starting material. (author)

  11. Titanium compacts produced by the pulvimetallurgical hydride-dehydride method for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Barreiro, M M [Materiales Dentales, Facultad de OdontologIa, Universidad de Buenos Aires, Marcelo T de Alvear 2142 (1122), Buenos Aires (Argentina); Grana, D R; Kokubu, G A [PatologIa I. Escuela de OdontologIa, Facultad de Medicina. Asociacion Odontologica Argentina-Universidad del Salvador, Tucuman 1845 (1050) Buenos Aires (Argentina); Luppo, M I; Mintzer, S; Vigna, G, E-mail: mbarreiro@mater.odon.uba.a, E-mail: dgrana@usal.edu.a, E-mail: luppo@cnea.gov.a, E-mail: vigna@cnea.gov.a [Departamento Materiales, Comision Nacional de Energia Atomica, Gral Paz 1499 (B1650KNA), San MartIn, Buenos Aires (Argentina)

    2010-04-15

    Titanium powder production by the hydride-dehydride method has been developed as a non-expensive process. In this work, commercially pure grade two Ti specimens were hydrogenated. The hydrided material was milled in a planetary mill. The hydrided titanium powder was dehydrided and then sieved to obtain a particle size between 37 and 125{mu}m in order to compare it with a commercial powder produced by chemical reduction with a particle size lower than 150{mu}m. Cylindrical green compacts were obtained by uniaxial pressing of the powders at 343 MPa and sintering in vacuum. The powders and the density of sintered compacts were characterized, the oxygen content was measured and in vivo tests were performed in the tibia bones of Wistar rats in order to evaluate their biocompatibility. No differences were observed between the materials which were produced either with powders obtained by the hydride-dehydride method or with commercial powders produced by chemical reduction regarding modifications in compactation, sintering and biological behaviour.

  12. Titanium compacts produced by the pulvimetallurgical hydride-dehydride method for biomedical applications

    International Nuclear Information System (INIS)

    Barreiro, M M; Grana, D R; Kokubu, G A; Luppo, M I; Mintzer, S; Vigna, G

    2010-01-01

    Titanium powder production by the hydride-dehydride method has been developed as a non-expensive process. In this work, commercially pure grade two Ti specimens were hydrogenated. The hydrided material was milled in a planetary mill. The hydrided titanium powder was dehydrided and then sieved to obtain a particle size between 37 and 125 μm in order to compare it with a commercial powder produced by chemical reduction with a particle size lower than 150 μm. Cylindrical green compacts were obtained by uniaxial pressing of the powders at 343 MPa and sintering in vacuum. The powders and the density of sintered compacts were characterized, the oxygen content was measured and in vivo tests were performed in the tibia bones of Wistar rats in order to evaluate their biocompatibility. No differences were observed between the materials which were produced either with powders obtained by the hydride-dehydride method or with commercial powders produced by chemical reduction regarding modifications in compactation, sintering and biological behaviour.

  13. Biovailability of copper and zinc in pig and cattle slurries

    NARCIS (Netherlands)

    Jakubus, M.; Dach, J.; Starmans, D.A.J.

    2013-01-01

    Slurry is an important source of macronutrients, micro-nutrients and organic matter. Despite the considerable fertilizer value of slurry, it may be abundant in amounts of copper and zinc originating from dietary. The study presents quantitative changes in copper and zinc in individual slurries (pig

  14. Radio-frequency slurry-density measurement for dredging pipelines

    NARCIS (Netherlands)

    van Eeten, M.J.C.

    2011-01-01

    Hydraulic dredgers make use of a density meter to measure the instantaneous density in the slurry transport pipeline, primarily for process control and production calculation. the current ‘golden’ standard for slurry density measurement is the radioactive density meter. It is based on a slurry

  15. Development of a phenomenological model for coal slurry atomization

    Energy Technology Data Exchange (ETDEWEB)

    Dooher, J.P. [Adelphi Univ., Garden City, NY (United States)

    1995-11-01

    Highly concentrated suspensions of coal particles in water or alternate fluids appear to have a wide range of applications for energy production. For enhanced implementation of coal slurry fuel technology, an understanding of coal slurry atomization as a function coal and slurry properties for specific mechanical configurations of nozzle atomizers should be developed.

  16. Stress induced reorientation of vanadium hydride

    International Nuclear Information System (INIS)

    Beardsley, M.B.

    1977-10-01

    The critical stress for the reorientation of vanadium hydride was determined for the temperature range 180 0 to 280 0 K using flat tensile samples containing 50 to 500 ppM hydrogen by weight. The critical stress was observed to vary from a half to a third of the macroscopic yield stress of pure vanadium over the temperature range. The vanadium hydride could not be stress induced to precipitate above its stress-free precipitation temperature by uniaxial tensile stresses or triaxial tensile stresses induced by a notch

  17. Anaerobic digestion of dairy farm slurry

    Energy Technology Data Exchange (ETDEWEB)

    Bell, C

    1973-04-01

    Bell described the intermittent operation of a pilot-scale anaerobic digester receiving dilute dairy farm slurry. A 65 to 75 percent reduction of the ''permanganate (COD) value'' could be obtained at 35/sup 0/ and a 60 day detention time. Methane content of the gases ranged between 40 and 70 percent.

  18. Coal slurry combustion and technology. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    Volume II contains papers presented at the following sessions of the Coal Slurry Combustion and Technology Symposium: (1) bench-scale testing; (2) pilot testing; (3) combustion; and (4) rheology and characterization. Thirty-three papers have been processed for inclusion in the Energy Data Base. (ATT)

  19. Bio-slurry as fertilizer : is bio-slurry from household digesters a better fertilizer than manure? : a literature review

    NARCIS (Netherlands)

    Bonten, L.T.C.; Zwart, K.B.; Rietra, R.P.J.J.; Postma, R.; Haas, de M.J.G.; Nysingh, S.L.

    2014-01-01

    In many developing countries manure is anaerobically digested to produce biogas. The residue of manure digestion, bio-slurry, can be used as fertilizer for crop production and aquaculture. This study compared bio-slurry and manure as fertilizers. Nutrients in bio-slurry, especially nitrogen, are

  20. ACCEPTABILITY ENVELOPE FOR METAL HYDRIDE-BASED HYDROGEN STORAGE SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, B.; Corgnale, C.; Tamburello, D.; Garrison, S.; Anton, D.

    2011-07-18

    The design and evaluation of media based hydrogen storage systems requires the use of detailed numerical models and experimental studies, with significant amount of time and monetary investment. Thus a scoping tool, referred to as the Acceptability Envelope, was developed to screen preliminary candidate media and storage vessel designs, identifying the range of chemical, physical and geometrical parameters for the coupled media and storage vessel system that allow it to meet performance targets. The model which underpins the analysis allows simplifying the storage system, thus resulting in one input-one output scheme, by grouping of selected quantities. Two cases have been analyzed and results are presented here. In the first application the DOE technical targets (Year 2010, Year 2015 and Ultimate) are used to determine the range of parameters required for the metal hydride media and storage vessel. In the second case the most promising metal hydrides available are compared, highlighting the potential of storage systems, utilizing them, to achieve 40% of the 2010 DOE technical target. Results show that systems based on Li-Mg media have the best potential to attain these performance targets.

  1. The effect of hydrides on the growth of zirconia

    International Nuclear Information System (INIS)

    Ekbom, L.R.

    1982-01-01

    The purpose of the present experiment has been to verify a hypothesis that accelerated corrosion of hydride containin Zircaloy is caused by small pores formed in the oxide by the evolution of hydrogen during oxidation of hydrides. The work has been divided into two parts: specimen preparation and microscopy. ZrO 2 is difficult to work with because of the high compressive stress which exists in the oxide. The most interesting area to study if any hydrogen pores exist, is the metal-oxide interface. Both transmission and scanning electron microscopy were used in the study. Neither of these methods gave any useful information with regard to the original hypothesis. However, a few interesting observations were made on the structure of the oxide at the metal-oxide interface. When the metal had been removed by electropolishing it was seen that the inner surface of the oxide consisted of 0,2-0.3 μ long and 0.1 μ thick wormlike protuberances of oxide. These features could not be seen when the metal had been removed by chemical etching. An attempt to determine whether or not this structure is an artefact introduced by electropolishing was inconclusive but indicated that the structure probably is real. (Author)

  2. In situ hydride formation in titanium during focused ion milling.

    Science.gov (United States)

    Ding, Rengen; Jones, Ian P

    2011-01-01

    It is well known that titanium and its alloys are sensitive to electrolytes and thus hydrides are commonly observed in electropolished foils. In this study, focused ion beam (FIB) milling was used to prepare thin foils of titanium and its alloys for transmission electron microscopy. The results show the following: (i) titanium hydrides were observed in pure titanium, (ii) the preparation of a bulk sample in water or acid solution resulted in the formation of more hydrides and (iii) FIB milling aids the precipitation of hydrides, but there were never any hydrides in Ti64 and Ti5553.

  3. Rheological Characterization of Unusual DWPF Slurry Samples

    International Nuclear Information System (INIS)

    Koopman, D. C.

    2005-01-01

    A study was undertaken to identify and clarify examples of unusual rheological behavior in Defense Waste Processing Facility (DWPF) simulant slurry samples. Identification was accomplished by reviewing sludge, Sludge Receipt and Adjustment Tank (SRAT) product, and Slurry Mix Evaporator (SME) product simulant rheological results from the prior year. Clarification of unusual rheological behavior was achieved by developing and implementing new measurement techniques. Development of these new methods is covered in a separate report, WSRC-TR-2004-00334. This report includes a review of recent literature on unusual rheological behavior, followed by a summary of the rheological measurement results obtained on a set of unusual simulant samples. Shifts in rheological behavior of slurries as the wt. % total solids changed have been observed in numerous systems. The main finding of the experimental work was that the various unusual DWPF simulant slurry samples exhibit some degree of time dependent behavior. When a given shear rate is applied to a sample, the apparent viscosity of the slurry changes with time rather than remaining constant. These unusual simulant samples are more rheologically complex than Newtonian liquids or more simple slurries, neither of which shows significant time dependence. The study concludes that the unusual rheological behavior that has been observed is being caused by time dependent rheological properties in the slurries being measured. Most of the changes are due to the effect of time under shear, but SB3 SME products were also changing properties while stored in sample bottles. The most likely source of this shear-related time dependence for sludge is in the simulant preparation. More than a single source of time dependence was inferred for the simulant SME product slurries based on the range of phenomena observed. Rheological property changes were observed on the time-scale of a single measurement (minutes) as well as on a time scale of hours

  4. Effects of δ-hydride precipitation at a crack tip on crack propagation in delayed hydride cracking of Zircaloy-2

    Energy Technology Data Exchange (ETDEWEB)

    Kubo, T., E-mail: kubo@nfd.co.jp [Nippon Nuclear Fuel Development Co., Ltd., 2163 Narita-cho, Oarai-machi, Ibaraki 311-1313 (Japan); Kobayashi, Y. [M.O.X. Co., Ltd., 1828-520 Hirasu-cho, Mito, Ibaraki 311-0853 (Japan)

    2013-08-15

    Highlights: • Steady state crack velocity of delayed hydride cracking in Zircaloy-2 was analyzed. • A large stress peak is induced at an end of hydride by volume expansion of hydride. • Hydrogen diffuses to the stress peak, thereby accelerating steady hydride growth. • Crack velocity was estimated from the calculated hydrogen flux into the stress peak. • There was good agreement between calculation results and experimental data. -- Abstract: Delayed hydride cracking (DHC) of Zircaloy-2 is one possible mechanism for the failure of boiling water reactor fuel rods in ramp tests at high burnup. Analyses were made for hydrogen diffusion around a crack tip to estimate the crack velocity of DHC in zirconium alloys, placing importance on effects of precipitation of δ-hydride. The stress distribution around the crack tip is significantly altered by precipitation of hydride, which was strictly analyzed using a finite element computer code. Then, stress-driven hydrogen diffusion under the altered stress distribution was analyzed by a differential method. Overlapping of external stress and hydride precipitation at a crack tip induces two stress peaks; one at a crack tip and the other at the front end of the hydride precipitate. Since the latter is larger than the former, more hydrogen diffuses to the front end of the hydride precipitate, thereby accelerating hydride growth compared with that in the absence of the hydride. These results indicated that, after hydride was formed in front of the crack tip, it grew almost steadily accompanying the interaction of hydrogen diffusion, hydride growth and the stress alteration by hydride precipitation. Finally, crack velocity was estimated from the calculated hydrogen flux into the crack tip as a function of temperature, stress intensity factor and material strength. There was qualitatively good agreement between calculation results and experimental data.

  5. Metal hydrides for hydrogen storage in nickel hydrogen batteries

    International Nuclear Information System (INIS)

    Bittner, H.F.; Badcock, C.C.; Quinzio, M.V.

    1984-01-01

    Metal hydride hydrogen storage in nickel hydrogen (Ni/H 2 ) batteries has been shown to increase battery energy density and improve battery heat management capabilities. However the properties of metal hydrides in a Ni/H 2 battery environment, which contains water vapor and oxygen in addition to the hydrogen, have not been well characterized. This work evaluates the use of hydrides in Ni/H 2 batteries by fundamental characterization of metal hydride properties in a Ni/H 2 cell environment. Hydrogen sorption properties of various hydrides have been measured in a Ni/H 2 cell environment. Results of detailed thermodynamic and kinetic studies of hydrogen sorption in LaNi 5 in a Ni/H 2 cell environment are presented. Long-term cycling studies indicate that degradation of the hydride can be minimized by cycling between certain pressure limits. A model describing the mechanism of hydride degradation is presented

  6. Characterisation of hydrides in a zirconium alloy, by EBSD

    International Nuclear Information System (INIS)

    Ubhi, H.S.; Larsen, K.

    2012-01-01

    Zirconium alloys are used in nuclear reactors owing to their low capture cross-section for thermal neutrons and good mechanical and corrosion properties. However, they do suffer from delayed hydrogen cracking (DHC) due to formation of hydride particles. This study shows how the electron back-scatter diffraction (EBSD) technique can be used to characterise hydrides and their orientation relationship with the matrix. Hydrided EB weld specimens were prepared by electro-polishing, characterised using Oxford instruments AZtecHKL EBSD apparatus and software attached to a FEG SEM. Hydrides were found to exist as fine intra granular plates and having the Blackburn orientation relationship, i.e. (0002)Zr//(111)hydride and (1120)Zr//(1-10)hydride. The hydrides were also found to contain sigma 3 boundaries as well as local misorientations. (author)

  7. Hydride formation on deformation twin in zirconium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ju-Seong [Korea Atomic Energy Research Institute, 989-111 Daedeokdaero, Yuseong-gu, Daejeon, 305-353 (Korea, Republic of); Kim, Sung-Dae [Korea Institute of Material Science (KIMS), 797 Changwondaero, Changwon, Gyeongnam, 642-831 (Korea, Republic of); Yoon, Jonghun, E-mail: yooncsmd@gmail.com [Department of Mechanical Engineering, Hanyang University, 1271 Sa3-dong, Sangrok-gu, Ansan-si, Gyeonggi-do, 426-791 (Korea, Republic of)

    2016-12-15

    Hydrides deteriorate the mechanical properties of zirconium (Zr) alloys used in nuclear reactors. Intergranular hydrides that form along grain boundaries have been extensively studied due to their detrimental effects on cracking. However, it has been little concerns on formation of Zr hydrides correlated with deformation twins which is distinctive heterogeneous nucleation site in hexagonal close-packed metals. In this paper, the heterogeneous precipitation of Zr hydrides at the twin boundaries was visualized using transmission electron microscopy. It demonstrates that intragranular hydrides in the twinned region precipitates on the rotated habit plane by the twinning and intergranular hydrides precipitate along the coherent low energy twin boundaries independent of the conventional habit planes. Interestingly, dislocations around the twin boundaries play a substantial role in the nucleation of Zr hydrides by reducing the misfit strain energy.

  8. Enhanced biogas production from anaerobic co-digestion of pig slurry and horse manure with mechanical pre-treatment.

    Science.gov (United States)

    Lopes, Madalena; Baptista, Patrícia; Duarte, Elizabeth; Moreira, António L N

    2018-01-02

    Enhanced biogas production from anaerobic co-digestion of pig slurry and horse manure with mechanical pre-treatment. In this study, co-digestion of horse manure and pig slurry was investigated in a continuously stirred tank reactor, with a mechanical pre-treatment. Experiments were conducted at 37°C, with hydraulic retention times of 23 days and increasing shares of horse manure, corresponding to different horse manure to pig slurry ratios (HM:PS) equal to 0:100, 10:90, 13:87 and 20:80, in terms of percentage of inlet volatile solids (%VS inlet). The results show that the best synergetic effect between the microbial consortia of pig slurry and the high Carbon to Nitrogen ratio (C/N) of horse manure is obtained for the mixture of 20:80%VS inlet, yielding the highest specific methane production (SMP = 142.6 L kg TCOD -1 ) and the highest soluble chemical oxygen demand (SCOD) reduction (68.5%), due to the high volatile dissolved solids content and soluble chemical oxygen demand to total chemical oxygen demand ratio (SCOD/TCOD). Thus, co-digestion of horse manure and pig slurry is shown to be a promising approach for biogas production and as a waste treatment solution. Furthermore, the analysis provides a methodology for the pre-treatment of these substrates and to investigate into the best combination for improved biogas production.

  9. A Study on the Radial Hydride Assisted Delayed Hydride Cracking of Zircaloy

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Jin-Ho; Lee, Ji-Min; Kim, Yong-Soo [Hanyang University, Seoul (Korea, Republic of)

    2015-05-15

    Extensive studies have been done on understanding of DHC(Delayed hydride cracking) phenomenon since several zirconium alloy pressure tubes failed in nuclear reactor in the 1970s. Recently, long-term dry storage strategy has been considered seriously in order to manage spent nuclear fuel in Korea and other countries around the world. Consequentially, many researches have been investigated the degradation mechanisms which will threaten the spent fuel integrity during dry storage and showed that hydrogen related phenomenon such as hydride reorientation and DHC are the critical factors. Especially, DHC is the direct cracking mechanism which can cause not only a through-wall defect but also a radiation leak to the environment. In addition, DHC can be enhanced by radial hydride as reported by Kim who demonstrate that radial hydrides clearly act as crack linkage path. This phenomenon is known as the radial hydride assisted DHC (RHA-DHC). Therefore, study on DHC is essential to ensure the safety of spent fuel. Finite element analysis will be carried out for the stress gradient evaluation around notch tip. A variation in thermal cycle which leads to change in hydrogen solid solution trajectory may be required. If the radial hydride precipitates at notch tip, we will investigate what conditions should be met. Ultimately, we will suggest the regulation criteria for long-term dry storage of spent nuclear fuel.

  10. Influências físicas sobre características químicas na compostagem da fracção sólida de chorume de bovinos leiteiros Influence of dairy cattle slurry solid fraction physical characteristics on chemical characteristics of composts

    Directory of Open Access Journals (Sweden)

    L. M. Brito

    2007-07-01

    covered and with 15 m³ outside the greenhouse, covered with a polyethylene film or with a geotextile film which allowed gas exchange but not rain infiltration. The piles covered with the geotextile film or uncovered reached higher temperatures compared with those covered with the polyethylene film because the oxygen could be exchanged from outside. When covered with polyethylene the temperatures were lower inside the piles with initial lower dry matter content. The physical characteristics such as temperature, moisture and aeration inside the piles were periodically related to chemical characteristics such as pH, electrical conductivity, organic matter, Kjeldahl N and C/N ratio. Organic matter losses were compared with N content throughout the composting period and it was concluded that the solid fraction from slurry can be composted with minimum N losses in static piles with a reduced number of turnings.

  11. Method for preparation of uranium hydride

    International Nuclear Information System (INIS)

    Gorski, M.S.; Goncalves, Miriam; Mirage, A.; Lima, W. de.

    1985-01-01

    A method for preparation of Uranium Hydride starting from Hidrogen and Uranium is described. In the temperature range of 250 0 up to 350 0 C, and pressures above 10torr, Hydrogen reacts smoothly with Uranium turnings forming a fine black or dark gray powder (UH 3 ). Samples containing a significant amount of oxides show a delay before the reaction begging. (Author) [pt

  12. Hydrogen isotope exchange in metal hydride columns

    International Nuclear Information System (INIS)

    Wiswall, R.; Reilly, J.; Bloch, F.; Wirsing, E.

    1977-01-01

    Several metal hydrides were shown to act as chromatographic media for hydrogen isotopes. The procedure was to equilibrate a column of hydride with flowing hydrogen, inject a small quantity of tritium tracer, and observe its elution behavior. Characteristic retention times were found. From these and the extent of widening of the tritium band, the heights equivalent to a theoretical plate could be calculated. Values of around 1 cm were obtained. The following are the metals whose hydrides were studied, together with the temperature ranges in which chromatographic behavior was observed: vanadium, 0 to 70 0 C; zirconium, 500 to 600 0 C; LaNi 5 , -78 to +30 0 C; Mg 2 Ni, 300 to 375 0 C; palladium, 0 to 70 0 C. A dual-temperature isotope separation process based on hydride chromatography was demonstrated. In this, a column was caused to cycle between two temperatures while being supplied with a constant stream of tritium-traced hydrogen. Each half-cycle was continued until ''breakthrough,'' i.e., until the tritium concentration in the effluent was the same as that in the feed. Up to that point, the effluent was enriched or depleted in tritium, by up to 20%

  13. Magnesium hydrides and their phase transitions

    Czech Academy of Sciences Publication Activity Database

    Paidar, Václav

    2016-01-01

    Roč. 41, č. 23 (2016), s. 9769-9773 ISSN 0360-3199 R&D Projects: GA MŠk(CZ) LD13069 Institutional support: RVO:68378271 Keywords : hydrogen * magnesium and transition metal hydrides * crystal structure stability * displacive phase transformations Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.582, year: 2016

  14. Are RENiAl hydrides metallic?

    Czech Academy of Sciences Publication Activity Database

    Eichinger, K.; Havela, L.; Prokleška, J.; Stelmakhovych, O.; Daniš, S.; Šantavá, Eva; Miliyanchuk, K.

    2009-01-01

    Roč. 100, č. 9 (2009), s. 1200-1202 ISSN 1862-5282 Grant - others:GA ČR(CZ) GA202/07/0418 Institutional research plan: CEZ:AV0Z10100520 Keywords : rare earth metals * magnetism * hydrides Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.862, year: 2009

  15. Lithium hydride hydrolysis: experimental and kinetic study

    International Nuclear Information System (INIS)

    Charton, S.; Maupoix, C.; Brevet, A.; Delaunay, F.; Heintz, O.; Saviot, L.

    2006-01-01

    In this work has been studied the contribution of various analyses techniques in the framework, on the one hand of revealing the mechanisms implied in lithium hydride hydrolysis, and on the other hand of studying the kinetics of hydrogen production. Among the methods recently investigated, Raman spectroscopy, XPS and SIMS seem to be particularly attractive. (O.M.)

  16. Peculiarities of formation of zirconium aluminides in hydride cycle mode

    International Nuclear Information System (INIS)

    Muradyan, G.N.

    2016-01-01

    The zirconium aluminides are promising structural materials in aerospace, mechanical engineering, chemical industry, etc. They are promising for manufacturing of heat-resistant wires, that will improve the reliability and efficiency of electrical networks. In the present work, the results of study of zirconium aluminides formation in the Hydride Cycle (HC) mode, developed in the Laboratory of high-temperature synthesis of the Institute of Chemical Physics of NAS RA, are described. The formation of zirconium aluminides in HC proceeded according to the reaction xZrH_2+(1-x)Al → alloy Zr_xAl(1-x)+H_2↑. The samples were certified using: chemical analysis to determine the content of hydrogen (pyrolysis method); differential thermal analysis (DTA, derivatograph Q-1500, T_heating = 1000°C, rate 20°C/min); X-ray analysis (XRD, diffractometer DRON-0.5). The influences of the ratio of powders ZrH_2/Al in the reaction mixture, compacting pressure, temperature and heating velocity on the characteristics of the synthesized aluminides were determined. In HC, the solid solutions of Al in Zr, single phase ZrAl_2 and ZrAl_3 aluminides and Zr_3AlH_4.49 hydride were synthesized. Formation of aluminides in HC mode took place by the solid-phase mechanism, without melting of aluminum. During processing, the heating of the initial charge up to 540°C resulted in the decomposition of zirconium hydride (ZrH_2) to HCC ZrH_1.5, that interacted with aluminum at 630°C forming FCC alumohydride of zirconium. Further increase of the temperature up to 800°C led to complete decomposition of the formed alumohydride of zirconium. The final formation of the zirconium aluminide occurred at 1000-1100°C in the end of HC process. Conclusion: in the synthesis of zirconium aluminides, the HC mode has several significant advantages over the conventional modes: lower operating temperatures (1000°C instead of 1800°C); shorter duration (1.5-2 hours instead of tens of hours); the availability of

  17. Direct hydride shift mechanism and stereoselectivity of P450nor confirmed by QM/MM calculations.

    Science.gov (United States)

    Krámos, Balázs; Menyhárd, Dóra K; Oláh, Julianna

    2012-01-19

    Nitric oxide reductase (P450(nor)) found in Fusarium oxysporum catalyzes the reduction of nitric oxide to N(2)O in a multistep process. The reducing agent, NADH, is bound in the distal pocket of the enzyme, and direct hydride transfer occurs from NADH to the nitric oxide bound heme enzyme, forming intermediate I. Here we studied the possibility of hydride transfer from NADH to both the nitrogen and oxygen of the heme-bound nitric oxide, using quantum chemical and combined quantum mechanics/molecular mechanics (QM/MM) calculations, on two different protein models, representing both possible stereochemistries, a syn- and an anti-NADH arrangement. All calculations clearly favor hydride transfer to the nitrogen of nitric oxide, and the QM-only barrier and kinetic isotope effects are good agreement with the experimental values of intermediate I formation. We obtained higher barriers in the QM/MM calculations for both pathways, but hydride transfer to the nitrogen of nitric oxide is still clearly favored. The barriers obtained for the syn, Pro-R conformation of NADH are lower and show significantly less variation than the barriers obtained in the case of anti conformation. The effect of basis set and wide range of functionals on the obtained results are also discussed.

  18. Environmental Consequences of Pig Slurry Treatment Technologies

    DEFF Research Database (Denmark)

    ten Hoeve, Marieke

    occur during manure storage and after field application. The main emissions are ammonia, nitrous oxide, methane, carbon dioxide, nitrate, phosphorus and odour. Slurry treatment technologies have been and are being developed in order to reduce the environmental impacts of manure. However, it is important...... and excluding biogenic carbon, marine and freshwater eutrophication potential, terrestrial acidification and eutrophication potential, and fossil resource depletion potential. The different types of treatment technologies showed varying environmental profiles, meaning that one type of technology was beneficial...... technology, or co-substrate for anaerobic digestion). With respect to odorous emissions, an LCIA method was developed, but due to a lack of data it proved difficult to include odour in LCA. Regulations appear to have an influence on the environmental impacts of slurry treatment. A decrease in N application...

  19. Pump transients in FGD slurry systems

    International Nuclear Information System (INIS)

    Ponce-Campos, C.D., Thoy, C.T.

    1990-01-01

    In this paper, the start-up transient of a limestone slurry system used for a power plant scrubber is discussed. Particular characteristics of these kind of systems are pointed out and incorporated into an ad-hoc numerical model. Three possible start-up scenarios are discussed and compared with field experimental data. The results illustrate well the importance of air pocket purging prior to system start-up

  20. Fischer-Tropsch Slurry Reactor modeling

    Energy Technology Data Exchange (ETDEWEB)

    Soong, Y.; Gamwo, I.K.; Harke, F.W. [Pittsburgh Energy Technology Center, PA (United States)] [and others

    1995-12-31

    This paper reports experimental and theoretical results on hydrodynamic studies. The experiments were conducted in a hot-pressurized Slurry-Bubble Column Reactor (SBCR). It includes experimental results of Drakeol-10 oil/nitrogen/glass beads hydrodynamic study and the development of an ultrasonic technique for measuring solids concentration. A model to describe the flow behavior in reactors was developed. The hydrodynamic properties in a 10.16 cm diameter bubble column with a perforated-plate gas distributor were studied at pressures ranging from 0.1 to 1.36 MPa, and at temperatures from 20 to 200{degrees}C, using a dual hot-wire probe with nitrogen, glass beads, and Drakeol-10 oil as the gas, solid, and liquid phase, respectively. It was found that the addition of 20 oil wt% glass beads in the system has a slight effect on the average gas holdup and bubble size. A well-posed three-dimensional model for bed dynamics was developed from an ill-posed model. The new model has computed solid holdup distributions consistent with experimental observations with no artificial {open_quotes}fountain{close_quotes} as predicted by the earlier model. The model can be applied to a variety of multiphase flows of practical interest. An ultrasonic technique is being developed to measure solids concentration in a three-phase slurry reactor. Preliminary measurements have been made on slurries consisting of molten paraffin wax, glass beads, and nitrogen bubbles at 180 {degrees}C and 0.1 MPa. The data show that both the sound speed and attenuation are well-defined functions of both the solid and gas concentrations in the slurries. The results suggest possibilities to directly measure solids concentration during the operation of an autoclave reactor containing molten wax.

  1. Comparison of rheological evaluation techniques and turbulent flow prediction of a simulated nuclear waste melter slurry

    International Nuclear Information System (INIS)

    Carleson, T.E.; Hart, R.E.; Drown, D.C.; Peterson, M.E.

    1987-03-01

    An experimental study was performed on a simulated nuclear waste slurry containing the type of waste sludge and glass-forming chemicals that will be converted to a stable glass in a high-temperature furnace. The rheological properties of the slurry must be determined in order to design the transport and mixing systems. The rheological parameters for the slurry were determined by a variety of viscometers including a rotational viscometer, a capillary tube viscometer, and a pipe flow apparatus. Experiments revealed the absence of wall slip and sufficient non-Newtonian behavior to require adjustments of the results. The slurry was characterized as a yield pseudoplastic fluid. Different rheological constants were obtained for all three viscometers. Predictions of the shear stress as a function of shear rate showed good agreement between the constants determined by the rotational viscometer and the pipe loop apparatus. Laminar and turbulent flows in the pipe loop correlated closely with a recent theoretical model. 16 refs., 16 figs., 5 tabs

  2. Determination of particle size distribution of salt crystals in aqueous slurries

    International Nuclear Information System (INIS)

    Miller, A.G.

    1977-10-01

    A method for determining particle size distribution of water-soluble crystals in aqueous slurries is described. The salt slurries, containing sodium salts of predominantly nitrate, but also nitrite, sulfate, phosphate, aluminates, carbonate, and hydroxide, occur in radioactive, concentrated chemical waste from the reprocessing of nuclear fuel elements. The method involves separating the crystals from the aqueous phase, drying them, and then dispersing the crystals in a nonaqueous medium based on nitroethane. Ultrasonic treatment is important in dispersing the sample into its fundamental crystals. The dispersed crystals are sieved into appropriate size ranges for counting with a HIAC brand particle counter. A preponderance of very fine particles in a slurry was found to increase the difficulty of effecting complete dispersion of the crystals because of the tendency to retain traces of aqueous mother liquor. Traces of moisture produce agglomerates of crystals, the extent of agglomeration being dependent on the amount of moisture present. The procedure is applicable to particles within the 2 to 600 μm size range of the HIAC particle counter. The procedure provides an effective means for measuring particle size distribution of crystals in aqueous salt slurries even when most crystals are less than 10 μm in size. 19 figures

  3. Development of laboratory apparatus dedicated to the study of hydride--dehydride reactions

    International Nuclear Information System (INIS)

    Wemple, R.P.; Kass, W.J.

    1979-07-01

    Hydrogen-compatible laboratory apparatus has been designed and developed to study hydride--dehydride reactions at elevated pressures and temperatures. The system has operated at pressures and temperatures up to 34 MPa and 550 0 C during experiments conducted on LiAlH 4 and NiZr. Instrumentation incorporated into the system also allows differential thermal analysis and acoustic emission data to be collected as the chemical reactions progress. 13 figures

  4. Multi-scale characterization of nanostructured sodium aluminum hydride

    Science.gov (United States)

    NaraseGowda, Shathabish

    instruments were utilized for this work and their data collection and analysis are reported. Quasielastic neutron scattering experiments were conducted at NIST Center for Neutron Research to characterize atomic hydrogen diffusion in bulk and nano-confined NaAlH4. It was observed that upon confinement of NaAlH4, a significantly higher fraction of hydrogen atoms were involved in diffusive motion on the pico-second to nano-second timescales. However, the confinement had no impact on the lattice diffusivities (jump/hopping rates) of atomic hydrogen, indicating that the improved hydrogen release rates were not due to any kinetic destabilization effects. Instead, the investigation strongly suggested thermodynamic destabilization as the major effect of nano-confinement. The local interaction of the metal sites in metal organic frameworks with the infiltrated hydride was studied using extended x-ray absorption spectroscopy technique. The experiments were conducted at Center for Advanced Microstructures and Devices at Louisiana State University. The metal sites were found to be chemically un-altered, hence ruling out any catalytic role in the dehydrogenation at room temperatures. The fractal morphology of NaAlH4 was characterized by ultra-small angle x-ray scattering experiments performed at Argonne National Lab. The studies quantitatively estimated the extent of densification in the course of one desorption cycle. The particle sizes were found to increase two-fold during heat treatment. Also, the nano-confinement procedure was shown to produce dense mass fractals as opposed to pristine NaAlH4, exhibiting a surface fractal morphology. Based on this finding, a new method to identify confined material from un-confined material in nano-composites was developed and is presented. Preliminary results of modeling and correlating multi-scale phenomena using a phase-field approach are also presented as the foundation for future work.

  5. Engineering properties of nuclear waste slurries - 16378

    International Nuclear Information System (INIS)

    Biggs, Simon; Fairweather, Michael; Hunter, Timothy; Omokanye, Qanitalillahi; Peakall, Jeffrey

    2009-01-01

    The type of particulate systems encountered in legacy nuclear waste slurries is highly complicated, with the aggregation and flow behaviour being at times very variable. However, deconstructing the complex overall slurry activity to singular particle-particle interactions can lead to a greater understanding of the mechanisms involved with particle aggregation, and so to predictions of their settling and flow in nuclear systems. Of particular importance to legacy waste is the role of salts in controlling the attraction of particles (and so in dictating the rheological properties of the system) as sludge may contain a variety of specific ions and generally have high ionic conductivity [1]. In this paper, particle-particle interactions are characterised using a number of complimentary methods, and their influence on resulting flow and bed compression is measured. The methods used to characterise the particle-particle interactions under various salt and pH conditions were electro-acoustic analysis (zeta potential) and atomic force microscopy (AFM). Following on from the analysis of particle-particle properties, bulk sediment behaviour was investigated using shear and compressive yield stress measurements, vital parameters in dictating flow and dewatering performance, respectively. Together, these techniques enable the characterisation of a range of particulate systems that may be encountered in legacy wastes, and results point to a number of important factors that can help explain the observed variability in industrial slurry behaviour. (authors)

  6. Slurry explosive containing an improved thickening agent

    Energy Technology Data Exchange (ETDEWEB)

    Wakazono, Y.; Otsuka, Y.

    1970-08-18

    A slurry explosive having stable physical properties and a thickening agent which when blended with a slurry explosive, maintains it in a uniform and stable state as a good suspended dispersion condition over a long period of time, are described. The slurry explosive has a composition consisting essentially of ammonium nitrate, or a mixture of ammonium nitrate and an alkali metal nitrate, or a mixture of ammonium nitrate and an alkaline earth metal nitrate, or a mixture of ammonium nitrate and an alkali metal nitrate and an alkaline earth metal nitrate, at least one member selected from the group consisting of 2,4,6-trinitrotoluene, aluminum, smokeless powder and fuels, and water, 0.1 to 2.0% guar gum, not more than 0.3% of a borate or borates, and/or not more than 20% of hexamethylene tetramine, and 0.02 to 2.0% of an antimony compound or compounds, all percents being by weight. (6 claims)

  7. Hydride vapor phase epitaxy growth of GaN, InGaN, ScN, and ScAIN

    NARCIS (Netherlands)

    Bohnen, T.

    2010-01-01

    Chemical vapor deposition (CVD); hydride vapor phase epitaxy (HVPE); gallium nitride (GaN); indium gallium nitride (InGaN); scandium nitride (ScN); scandium aluminum nitride (ScAlN); semiconductors; thin films; nanowires; III nitrides; crystal growth - We studied the HVPE growth of different III

  8. Field test of ethanol/bentonite slurry grouting into rock fracture

    International Nuclear Information System (INIS)

    Motoyuki Asada; Hitoshi Nakashima; Takashi Ishii; Sumio Horiuchi

    2006-01-01

    Crystalline rocks have fractures which may cause unexpected routes of groundwater seepage. Cement grouting is one of the most effective methods to minimize seepage; however, cement materials may not be suitable for the purpose of extra-long durability, because cement is neutralized or degraded by chemical and physical influence of chemical reaction. Natural clay like bentonite is one of the most promising materials for seepage barrier; however, water/bentonite grout is so viscous that enough amount of bentonite can not be grouted into rock fractures. To increase bentonite content in grout with low viscosity, the utilization of ethanol as a mixing liquid was studied. Ethanol suppresses bentonite swelling, and more bentonite can be injected more than that of water/bentonite slurry. In this paper, grouting into in-situ rock mass fracture from the ground surface was tested to investigate the barrier performance and workability of ethanol/bentonite slurry as a grouting material. (author)

  9. Hydrogen storage in metallic hydrides: the hydrides of magnesium-nickel alloys

    International Nuclear Information System (INIS)

    Silva, E.P. da.

    1981-01-01

    The massive and common use of hydrogen as an energy carrier requires an adequate solution to the problem of storing it. High pressure or low temperatures are not entirely satisfactory, having each a limited range of applications. Reversible metal hydrides cover a range of applications intermediate to high pressure gas and low temperature liquid hydrogen, retaining very favorable safety and energy density characteristics, both for mobile and stationary applications. This work demonstrates the technical viability of storing hydrogen in metal hydrides of magnesium-nickel alloys. Also, it shows that technology, a product of science, can be generated within an academic environment, of the goal is clear, the demand outstanding and the means available. We review briefly theoretical models relating to metal hydride properties, specially the thermodynamics properties relevant to this work. We report our experimental results on hydrides of magnesium-nickel alloys of various compositions including data on structure, hydrogen storage capacities, reaction kinetics, pressure-composition isotherms. We selected a promising alloy for mass production, built and tested a modular storage tank based on the hydrides of the alloy, with a capacity for storing 10 Nm sup(3) of hydrogen of 1 atm and 20 sup(0)C. The tank weighs 46,3 Kg and has a volume of 21 l. (author)

  10. SYNTHESIS AND STRUCTURE OF BIS(PHENYLTETRAMETHYLCYCLOPENTADIENYL)TITANIUM(III) HYDRIDE - THE FIRST MONOMERIC BIS(CYCLOPENTADIENYL)TITANIUM(III) HYDRIDE : The First Monomeric Bis(cyclopentadienyl)titanium(III) Hydride

    NARCIS (Netherlands)

    de Wolf, J.M.; Meetsma, A.; Teuben, J.H

    1995-01-01

    The first structurally characterized monomeric bis(cyclopentadienyl)titanium(III) hydride, (C(5)PhMe(4))(2)TiH (4), was synthesized by hydrogenolysis of (C(5)PhMe(4))(2)TiMe (5). Hydride 4 was found to be a monomeric bent sandwich by X-ray diffraction methods, and the pentamethylcyclopentadienyl

  11. The electrochemical impedance of metal hydride electrodes

    DEFF Research Database (Denmark)

    Valøen, Lars Ole; Lasia, Andrzej; Jensen, Jens Oluf

    2002-01-01

    The electrochemical impedance responses for different laboratory type metal hydride electrodes were successfully modeled and fitted to experimental data for AB5 type hydrogen storage alloys as well as one MgNi type electrode. The models fitted the experimental data remarkably well. Several AC......, explaining the experimental impedances in a wide frequency range for electrodes of hydride forming materials mixed with copper powder, were obtained. Both charge transfer and spherical diffusion of hydrogen in the particles are important sub processes that govern the total rate of the electrochemical...... hydrogen absorption/desorption reaction. To approximate the experimental data, equations describing the current distribution in porous electrodes were needed. Indications of one or more parallel reduction/oxidation processes competing with the electrochemical hydrogen absorption/desorption reaction were...

  12. Metal hydrides based high energy density thermal battery

    International Nuclear Information System (INIS)

    Fang, Zhigang Zak; Zhou, Chengshang; Fan, Peng; Udell, Kent S.; Bowman, Robert C.; Vajo, John J.; Purewal, Justin J.; Kekelia, Bidzina

    2015-01-01

    Highlights: • The principle of the thermal battery using advanced metal hydrides was demonstrated. • The thermal battery used MgH 2 and TiMnV as a working pair. • High energy density can be achieved by the use of MgH 2 to store thermal energy. - Abstract: A concept of thermal battery based on advanced metal hydrides was studied for heating and cooling of cabins in electric vehicles. The system utilized a pair of thermodynamically matched metal hydrides as energy storage media. The pair of hydrides that was identified and developed was: (1) catalyzed MgH 2 as the high temperature hydride material, due to its high energy density and enhanced kinetics; and (2) TiV 0.62 Mn 1.5 alloy as the matching low temperature hydride. Further, a proof-of-concept prototype was built and tested, demonstrating the potential of the system as HVAC for transportation vehicles

  13. Low frequency aeration of pig slurry affects slurry characteristics and emissions of greenhouse gases and ammonia.

    Science.gov (United States)

    Calvet, Salvador; Hunt, John; Misselbrook, Tom H

    2017-07-01

    Low frequency aeration of slurries may reduce ammonia (NH 3 ) and methane (CH 4 ) emissions without increasing nitrous oxide (N 2 O) emissions. The aim of this study was to quantify this potential reduction and to establish the underlying mechanisms. A batch experiment was designed with 6 tanks with 1 m 3 of pig slurry each. After an initial phase of 7 days when none of the tanks were aerated, a second phase of 4 weeks subjected three of the tanks to aeration (2 min every 6 h, airflow 10 m 3  h -1 ), whereas the other three tanks remained as a control. A final phase of 9 days was established with no aeration in any tank. Emissions of NH 3 , CH 4 , carbon dioxide (CO 2 ) and N 2 O were measured. In the initial phase no differences in emissions were detected, but during the second phase aeration increased NH 3 emissions by 20% with respect to the controls (8.48 vs. 7.07 g m -3  [slurry] d -1 , P emissions were 40% lower in the aerated tanks (2.04 vs. 3.39 g m -3  [slurry] d -1 , P emissions remained after the aeration phase had finished. No effect was detected for CO 2 , and no relevant N 2 O emissions were detected during the experiment. Our results demonstrate that low frequency aeration of stored pig slurry increases slurry pH and increases NH 3 emissions.

  14. Availability of phosphorus in cow slurry using isotopic labelling technique

    International Nuclear Information System (INIS)

    Pongsakul, P.; Bertelsen, F.; Gissel-Nielsen, G.

    1988-01-01

    A pot experiment was conducted to evaluate the influence of cow slurry on P uptake by corn and to estimate the readily available P in the slurry by using an isotopic labelling techique. Water-soluble P in soil was increased and isotopic equilibrium of available P was attained after labelled slurry was mixed thoroughly throughout the soil. Labelled slurry applied at planting increased the P uptake by corn, whereas the same amount applied one week before harvest did not affect the P uptake. It was estimated that 46-54% of the total P uptake in plants is derived from the slurry. The readily available P (the L-value) in the slurry was at least 26 mg/kg which equals 3.7% of the total P. (author)

  15. Biogas slurry pricing method based on nutrient content

    Science.gov (United States)

    Zhang, Chang-ai; Guo, Honghai; Yang, Zhengtao; Xin, Shurong

    2017-11-01

    In order to promote biogas-slurry commercialization, A method was put forward to valuate biogas slurry based on its nutrient contents. Firstly, element contents of biogas slurry was measured; Secondly, each element was valuated based on its market price, and then traffic cost, using cost and market effect were taken into account, the pricing method of biogas slurry were obtained lastly. This method could be useful in practical production. Taking cattle manure raw meterial biogas slurry and con stalk raw material biogas slurry for example, their price were 38.50 yuan RMB per ton and 28.80 yuan RMB per ton. This paper will be useful for recognizing the value of biogas projects, ensuring biogas project running, and instructing the cyclic utilization of biomass resources in China.

  16. Hydrides and Borohydrides of Light Elements

    Science.gov (United States)

    1947-12-04

    Troy, Attn: Inst. of Naval Science (30) Solar Aircraft Cu,, San Diego, Attn: Dr. M. A. Williamson " (31) INSMAT. N. J. for Itandard Oil Co., Esso Lab...with the other# iLD F.Re p. 8 ilt -ms" #61ggSotod that.. ir addition to thc impurity in the t~y..thr, an impurkty, prosumably aluminum hydride, in

  17. Facile Synthesis of Permethyl Yttrocene Hydride

    NARCIS (Netherlands)

    Haan, Klaas H. den; Teuben, Jan H.

    1984-01-01

    A convenient three step synthesis of (Cp*2YH)n (Cp* = C5Me5) is described starting with YCl3.3thf, in which Cp*2YCl.thf and Cp*2YCH(SiMe3)2 are intermediates, which could be isolated and characterized. The hydride is active in the activation of sp2 and sp3 C-H bonds as was demonstrated by the H-D

  18. HYDRIDE-RELATED DEGRADATION OF SNF CLADDING UNDER REPOSITORY CONDITIONS

    International Nuclear Information System (INIS)

    McCoy, K.

    2000-01-01

    The purpose and scope of this analysis/model report is to analyze the degradation of commercial spent nuclear fuel (CSNF) cladding under repository conditions by the hydride-related metallurgical processes, such as delayed hydride cracking (DHC), hydride reorientation and hydrogen embrittlement, thereby providing a better understanding of the degradation process and clarifying which aspects of the process are known and which need further evaluation and investigation. The intended use is as an input to a more general analysis of cladding degradation

  19. Heterogeneous ice slurry flow and concentration distribution in horizontal pipes

    International Nuclear Information System (INIS)

    Wang, Jihong; Zhang, Tengfei; Wang, Shugang

    2013-01-01

    Highlights: • A Mixture CFD model is applied to describe heterogeneous ice slurry flow. • The ice slurry rheological behavior is considered piecewise. • The coupled flow and concentration profiles in heterogeneous slurry flow is acquired. • The current numerical model achieves good balance between precision and universality. -- Abstract: Ice slurry is an energy-intensive solid–liquid mixture fluid which may play an important role in various cooling purposes. Knowing detailed flow information is important from the system design point of view. However, the heterogeneous ice slurry flow makes it difficult to be quantified due to the complex two phase flow characteristic. The present study applies a Mixture computational fluid dynamics (CFD) model based on different rheological behavior to characterize the heterogeneous ice slurry flow. The Mixture CFD model was firstly validated by three different experiments. Then the validated Mixture CFD model was applied to solve the ice slurry isothermal flow by considering the rheological behavior piecewise. Finally, the numerical solutions have displayed the coupled flow information, such as slurry velocity, ice particle concentration and pressure drop distribution. The results show that, the ice slurry flow distribution will appear varying degree of asymmetry under different operating conditions. The rheological behavior will be affected by the asymmetric flow distributions. When mean flow velocity is high, Thomas equation can be appropriate for describing ice slurry viscosity. While with the decreasing of mean flow velocity, the ice slurry behaves Bingham rheology. As compared with experimental pressure drop results, the relative errors of numerical computation are almost within ±15%. The Mixture CFD model is validated to be an effective model for describing heterogeneous ice slurry flow and could supply plentiful flow information

  20. Method of transporting radioactive slurry-like wastes

    Energy Technology Data Exchange (ETDEWEB)

    Kamiya, K; Yusa, H; Sugimoto, Y

    1975-06-30

    The object is to prevent blockage of a transporting tube to positively and effectively transport radioactive slurry wastes. A method of transporting radioactive slurry-like wastes produced in an atomic power plant, wherein liquid wastes produced in the power plant are diluted to form into a driving liquid, by which said radioactive slurry-like wastes are transported within the pipe, and said driving liquid is recovered as the liquid waste.

  1. Survey of state water laws affecting coal slurry pipeline development

    Energy Technology Data Exchange (ETDEWEB)

    Rogozen, M.B.

    1980-11-01

    This report summarizes state water laws likely to affect the development of coal slurry pipelines. It was prepared as part of a project to analyze environmental issues related to energy transportation systems. Coal slurry pipelines have been proposed as a means to expand the existing transportation system to handle the increasing coal shipments that will be required in the future. The availability of water for use in coal slurry systems in the coal-producing states is an issue of major concern.

  2. Spectrophotometric determination of volautile inorganic hydrides in binary gaseous mixtures

    International Nuclear Information System (INIS)

    Rezchikov, V.G.; Skachkova, I.N.; Kuznetsova, T.S.; Khrushcheva, V.V.

    1985-01-01

    A study was made on possibility of single and continuons analysis of binary mixtures (hydride-gas) for the content of volatile inorganic hydrides (VIH) from absorption spectra in the 185-280 nm band. Dependences of the percentage of VIH transmission on the wavelength are presented. It is shown that the maximum of their absorption depends on the element-hydrogen the bond length and binding energy. Detection limit for boron hydride was established to be n x 10 -3 % vol at 185-190 nm wavelength. Technique for spectrophotometric hydride determination in binary mixtures with hydrogen, argon, helium was developed. The technique provides the continuous control of gaseous mixture composition

  3. Identification of the zirconium hydrides metallography in zircaloy-2

    International Nuclear Information System (INIS)

    Garcia Gonzalez, F.

    1968-01-01

    Technique for the Identification of the zirconium hydrides in metallographic specimens have been developed. Microhardness, quantitative estimation and relative orientation of the present hydrides as well as grain size determination of the different Zircaloy-2 tube specimens have also been made. The specimens used were corrosion- tested in water during various periods of time at 300 degree castrating, prior to the metallographic examination. Reference specimens, as received, and heavily hydride specimens in a hydrogen atmosphere at 800 degree centigrees, have been used in the previous stages of the work. No difficulties have been met in this early stage of acquaintanceship with the zirconium hydrides. (Author) 5 refs

  4. Hydrogen Storage Engineering Center of Excellence Metal Hydride Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Motyka, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-05-31

    The Hydrogen Storage Engineering Center of Excellence (HSECoE) was established in 2009 by the U.S. Department of Energy (DOE) to advance the development of materials-based hydrogen storage systems for hydrogen-fueled light-duty vehicles. The overall objective of the HSECoE is to develop complete, integrated system concepts that utilize reversible metal hydrides, adsorbents, and chemical hydrogen storage materials through the use of advanced engineering concepts and designs that can simultaneously meet or exceed all the DOE targets. This report describes the activities and accomplishments during Phase 1 of the reversible metal hydride portion of the HSECoE, which lasted 30 months from February 2009 to August 2011. A complete list of all the HSECoE partners can be found later in this report but for the reversible metal hydride portion of the HSECoE work the major contributing organizations to this effort were the United Technology Research Center (UTRC), General Motors (GM), Pacific Northwest National Laboratory (PNNL), the National Renewable Energy Laboratory (NREL) and the Savannah River National Laboratory (SRNL). Specific individuals from these and other institutions that supported this effort and the writing of this report are included in the list of contributors and in the acknowledgement sections of this report. The efforts of the HSECoE are organized into three phases each approximately 2 years in duration. In Phase I, comprehensive system engineering analyses and assessments were made of the three classes of storage media that included development of system level transport and thermal models of alternative conceptual storage configurations to permit detailed comparisons against the DOE performance targets for light-duty vehicles. Phase 1 tasks also included identification and technical justifications for candidate storage media and configurations that should be capable of reaching or exceeding the DOE targets. Phase 2 involved bench-level testing and

  5. System and method for continuous solids slurry depressurization

    Science.gov (United States)

    Leininger, Thomas Frederick; Steele, Raymond Douglas; Cordes, Stephen Michael

    2017-07-11

    A system includes a first pump having a first outlet and a first inlet, and a controller. The first pump is configured to continuously receive a flow of a slurry into the first outlet at a first pressure and to continuously discharge the flow of the slurry from the first inlet at a second pressure less than the first pressure. The controller is configured to control a first speed of the first pump against the flow of the slurry based at least in part on the first pressure, wherein the first speed of the first pump is configured to resist a backflow of the slurry from the first outlet to the first inlet.

  6. State of the art on phase change material slurries

    International Nuclear Information System (INIS)

    Youssef, Ziad; Delahaye, Anthony; Huang Li; Trinquet, François; Fournaison, Laurence; Pollerberg, Clemens; Doetsch, Christian

    2013-01-01

    Highlights: ► A bibliographic study on PCM slurries. ► Clathrate Hydrate slurry, Microencapsulated PCM Slurry, shape-stabilized PCM slurries and Phase Change Material Emulsions. ► Formation, thermo-physical, rheological, heat transfers properties and applications of these four PCS systems. ► The use of thermal energy storage and distribution based on PCM slurries can improve the refrigerating machine performances. - Abstract: The interest in using phase change slurry (PCS) media as thermal storage and heat transfer fluids is increasing and thus leading to an enhancement in the number of articles on the subject. In air-conditioning and refrigeration applications, PCS systems represent a pure benefit resulting in the increase of thermal energy storage capacity, high heat transfer characteristics and positive phase change temperatures which can occur under low pressures. Hence, they allow the increase of energy efficiency and reduce the quantity of thermal fluids. This review describes the formation, thermo-physical, rheological, heat transfer properties and applications of four PCS systems: Clathrate hydrate slurry (CHS), Microencapsulated Phase Change Materials Slurry (MPCMS), shape-stabilized PCM slurries (SPCMSs) and Phase Change Material Emulsions (PCMEs). It regroups a bibliographic summary of important information that can be very helpful when such systems are used. It also gives interesting and valuable insights on the choice of the most suitable PCS media for laboratory and industrial applications.

  7. Comments to "Analysis of constant rate period of spray drying of slurry" by Liang et al., 2001

    DEFF Research Database (Denmark)

    Jørgensen, Kåre; Jensen, Anker Degn; Sloth, Jakob

    2006-01-01

    In the study by Liang et al. [2001. Analysis of constant rate period of spray drying of slurry. Chemical Engineering Science 56, 2205-2213] the Darcy flow of liquid through a pore system of primary particles to the surface of a slurry droplet was applied for the constant rate period. Steep primary...... particle concentration gradients inside -25 mu m droplets with a primary particle size of 0.2 mu m were observed. Unfortunately, the boundary condition at the droplet surface for the parabolic second-order PDE did not conserve the solid mass in the droplet, and the plots for the primary particle...

  8. Microbial decontamination of polluted soil in a slurry process

    International Nuclear Information System (INIS)

    Geerdink, M.J.; Kleijntjens, R.H.; Loosdrecht, M.C.M. van; Luyben, K.C.A.M.

    1996-01-01

    Oil-contaminated soil (2.3--17 g/kg), even soil with high clay and silt content, was remediated microbiologically in a slurry reactor. The presence of soil, however, limits the degradation rate of oil. In contrast with results form experiments using oil dispersed in water, the relative composition of the oil components in a soil slurry after degradation was about the same as that of the original oil. Thus the composition of the degraded oil is the same as that of the original oil, which is indicative for a physical, rather than a (bio)chemical, limitation on the oil degradation rate. About 70% of the contaminant was readily available and was degraded in less than eight days. The dual injected turbulent suspension (DITS) reactor is able to combine remediation of part of the contaminated (polydisperse) soil with separation of the soil into a heavily and a lightly polluted fraction. In continuous operation, lowering the overall soil residence time from 200 to 100 h did not significantly increase the oil concentration in the effluent soil. Therefore a soil residence time of less than 100 h is feasible. With a residence time of 100 h, overall oil degradation rates at the steady state were more than 70 times faster than in a comparable land farm. After treatment in a DITS reactor, the remaining oil in the contaminated soil fraction is slowly released from the soil. From a batch experiment it was found that another 10 weeks were needed to reach the Dutch reference level of 50 mg/kg. This can be done in a process with a low energy input, such as a landfarm

  9. ADVANCED COMPUTATIONAL MODEL FOR THREE-PHASE SLURRY REACTORS

    International Nuclear Information System (INIS)

    Ahmadi, Goodarz

    2004-01-01

    In this project, an Eulerian-Lagrangian formulation for analyzing three-phase slurry flows in a bubble column was developed. The approach used an Eulerian analysis of liquid flows in the bubble column, and made use of the Lagrangian trajectory analysis for the bubbles and particle motions. The bubble-bubble and particle-particle collisions are included the model. The model predictions are compared with the experimental data and good agreement was found An experimental setup for studying two-dimensional bubble columns was developed. The multiphase flow conditions in the bubble column were measured using optical image processing and Particle Image Velocimetry techniques (PIV). A simple shear flow device for bubble motion in a constant shear flow field was also developed. The flow conditions in simple shear flow device were studied using PIV method. Concentration and velocity of particles of different sizes near a wall in a duct flow was also measured. The technique of Phase-Doppler anemometry was used in these studies. An Eulerian volume of fluid (VOF) computational model for the flow condition in the two-dimensional bubble column was also developed. The liquid and bubble motions were analyzed and the results were compared with observed flow patterns in the experimental setup. Solid-fluid mixture flows in ducts and passages at different angle of orientations were also analyzed. The model predictions were compared with the experimental data and good agreement was found. Gravity chute flows of solid-liquid mixtures were also studied. The simulation results were compared with the experimental data and discussed A thermodynamically consistent model for multiphase slurry flows with and without chemical reaction in a state of turbulent motion was developed. The balance laws were obtained and the constitutive laws established

  10. Initiation of delayed hydride cracking in zirconium-2.5 wt% niobium

    International Nuclear Information System (INIS)

    Shalabi, A.F.; Meneley, D.A.

    1990-01-01

    Delayed hydride cracking in zirconium alloys is caused by the repeated precipitation and cracking of brittle hydrides. The growth kinetic of the hydrides have been measured to evaluate the critical hydride length for crack initiation. Hydride growth leading to crack initiation follows an approximate (time) 1/3 law on the average; crack propagation proceeds in a stepwise fashion. The critical length of hydride for crack initiation increases with stress and temperature. The fracture criterion for crack initiation predicts the critical hydride length at a give stress level and temperature. The fracture initiation mechanism of the hydride confirms the temperature effects for heating and cooling cycles under services loads. (orig.)

  11. Synthesis and characterization of cement slurries additives with epoxy resins - kinetics, thermodynamic and calorimetric analysis; Sintese e caracterizacao de pastas de cimento aditivadas com resinas epoxi - analises cineticas, termodinamicas e calorimetricas

    Energy Technology Data Exchange (ETDEWEB)

    Tavares, A.M.G.; Andrade Junior, M.A.S.; Cestari, A.R.; Vieira, E.F.S., E-mail: macleybiane@gmail.co [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil)

    2010-07-01

    Cement has been used in the world, presenting a wide versatility. However, due to its chemical nature, it is subject to several types of chemical damages, especially for agents of acidic nature. With the purpose of increase its life-time, new cement slurries have been modified with the addition of specific additives. The objective of this work is to modify cement slurries with epoxy resins, which promote higher resistance of those materials in relation to acid attacks. Three cement slurries were synthesized with epoxy resins and a standard slurries, which was composed by cement and water. After 30 days of hydration, the samples were characterized by XDR, FTIR and thermal analysis (TG and DSC). The hydration processes of the cement slurries were studied by heat-conduction microcalorimetry. A kinetic study of HCl interaction with the new slurries were performed by the batch methodology at 25, 35, 45 e 55 deg C. It was verified that the addition of the polymers delayed the processes of hydration of the slurries, decreasing the flow of heat released as a function of the amount of added resin and, increased the resistance of those slurries to the acid attack. (author)

  12. Impact of biogas slurry fertilizer on growth, quality and biochemical characteristics of ornamental lettuce 'Biscia Rossa'

    International Nuclear Information System (INIS)

    Jiaxiang, J.; Khalid, M.; Hong, Z.; Leqi, Y.; Dongqin, T.; Danfeng, H.

    2018-01-01

    Biogas slurry is a good source of plant nutrients and substituting chemical fertilizers with biogas slurry not only achieve resource utilization of slurry, but also reduce the amount of fertilizer. The present study investigated the influence of different ratios of biogas slurry fertilizer (BSF) on the growth, yield and quality characteristics of ornamental lettuce 'Biscia Rossa'. Results revealed that BSF significantly (p<0.05) improved the growth of ornamental lettuce on treatment with Z1 fertilizer; the plant height was increased by 12.66% and 16.75%, while leaf area was improved by 19.97% and 42.03%, in comparison with control group. The improvement in yield of ornamental lettuce was noted in varying degrees by BSF. The highest dry and fresh weights were observed in case of Z1 treated lettuce plants. The fresh weight was 33.52%, 44.77%, 43.96% and 49.04% higher than that of other 2 fertilizers and 2 control groups, respectively. Whereas the dry weight was 2.7 and 3.17-times greater than that of two control groups. The biogas slurry irrigation also considerably improved the quality of ornamental lettuce. Moreover, it was observed that vitamin C, anthocyanin, soluble sugar and protein were higher than that of control groups. Contrarily, the BSF led to decrease in nitrate-nitrogen content in ornamental lettuce. (author)

  13. Rheology of sludge-slurry grouts

    International Nuclear Information System (INIS)

    McDaniel, E.W.

    1980-10-01

    A series of rheograms was developed that relates the critical velocity (velocity where flow changes from laminar to turbulent) of a cementitious grout that incorporates a suspended sludge-slurry to the critical velocity of a reference grout made with a simulated waste solution. The sludge that is now in the Gunite waste tanks at the Oak Ridge National Laboratory (ORNL) will be suspended and pumped to the new waste storage tanks in Melton Valley. The sludge will then be blended with a cement mix base to form a grout which will be injected underground by the shale fracturing process. This report describes the materials, equipment, and techniques used in the laboratory studies to suspend sludges and mix sludge-slurry grouts that have flow properties similar to those of current shale fracturing grouts. Bentonite clay is an effective suspender in dilute NaNO 3 solutions; 15 wt % solids can be suspended with 2.0 wt % bentonite in a 0.1 M NaNO 3 solution. Other suspending materials were evaluated, but bentonite gave the best results. If a slurry grout becomes too viscous to pump, methods must be available to thin the mixture. A number of thinners, friction reducers, and plasticizers were examined. Q-Broxin, a thinner supplied by Baroid, reduced the velocity of a grout required for turbulent flow in a 5.0-cm (2-in.)-diam tube from 1.76 to 1.20 m/s (5.79 to 3.95 ft/s); FX-32C, a plasticizer supplied by Fox Industries, Inc., reduced the velocity from 1.76 to 0.75 m/s

  14. Impact of Spherical Frit Beads on Simulated DWPF Slurries

    International Nuclear Information System (INIS)

    SMITH, MICHAEL

    2005-01-01

    It has been shown that the rheological properties of simulated Defense Waste Processing Facility (DWPF) melter feed with the glass former frit as mostly (90 weight percent) solid spherical particles (referred to as beads) were improved as the feed was less viscous as compared to DWPF melter feed that contained the normal irregular shaped frit particles. Because the physical design of the DWPF Slurry Mix Evaporator (SME), Melter Feed Tank (MFT), and melter feed loop are fixed, the impact of changing the rheology might be very beneficial. Most importantly, higher weight percent total solids feed might be processed by reducing the rheological properties (specifically yield stress) of the feed. Additionally, if there are processing problems, such as air entrainment or pumping, these problems might be alleviated by reducing the rheological properties, while maintaining targeted throughputs. Rheology modifiers are chemical, physical, or a combination of the two and can either thin or thicken the rheology of the targeted slurry. The beads are classified as a physical rheological modifier in this case. Even though the improved rheological properties of the feed in the above mentioned DWPF tanks could be quite beneficial, it is the possibility of increased melt rate that is the main driver for the use of beaded glass formers. By improving the rheological properties of the feed, the weight percent solids of the feed could be increased. This higher weight percent solids (less water) feed could be processed faster by the melter as less energy would be required to evaporate the water, and more would be available for the actual melting of the waste and the frit. In addition, the use of beads to thin the feed could possibly allow for the use of a lower targeted acid stoichiometry in the feed preparation process (if in fact acid stoichiometry is being driven by feed rheology as opposed to feed chemistry). Previous work by the Savannah River National Laboratory (SRNL) with the lab

  15. Technical Development of Slurry Three-Dimensional Printer

    Science.gov (United States)

    Jiang, Cho-Pei; Hsu, Huang-Jan; Lee, Shyh-Yuan

    2017-09-01

    The aim of this paper is to review the technical development of slurry three-dimensional printer (3DP) which based on photo-polymerization and constrained surface method. Basically, slurry consists of ceramic powder, resin and photo-initiator. The light engines for solidifying the photo-curable slurry can be classified as laser, liquid crystal panel (LCD), digital light processing (DLP). The slurry can be reacted and solidified by selective ray according to the reaction spectrum of photo-initiator. Ceramic powder used in this study is zirconia oxide. Experimental results show that ceramic particle size affects the viscosity of slurry severely resulting in low accuracy and the occurrence of micro crack in the layer casting procedure. Therefore, the effect of particle size on the curability and accuracy of built green part is discussed. A single dental crown is proposed to be fabricated by these three light engines as a benchmark for comparison. In addition, the cost and the limitation are compared in the aspect of dental crown fabrication. Consequently, the lowest cost is LCD-type slurry 3DP system. DLP-type slurry 3DP can produce green body with the fastest fabrication time. The volumetric error of sintered part that made by these three fabrication methods is similar because the composition of slurry is the same.

  16. Drag reduction of dense fine-grained slurries

    Czech Academy of Sciences Publication Activity Database

    Vlasák, Pavel; Chára, Zdeněk; Štern, Petr

    2010-01-01

    Roč. 58, č. 4 (2010), s. 261-270 ISSN 0042-790X R&D Projects: GA ČR(CZ) GAP105/10/1574 Institutional research plan: CEZ:AV0Z20600510 Keywords : kaolin slurry * drag reduction * experimental investigation * peptization * slurry rheology Subject RIV: BK - Fluid Dynamics Impact factor: 0.553, year: 2010

  17. Cattle slurry on grassland - application methods and nitrogen use efficiency

    NARCIS (Netherlands)

    Lalor, S.T.J.

    2014-01-01

    Cattle slurry represents a significant resource on grassland-based farming systems. The objective of this thesis was to investigate and devise cattle slurry application methods and strategies that can be implemented on grassland farms to improve the efficiency with which nitrogen (N) in

  18. The Settling and Compaction of Nuclear Waste Slurries

    International Nuclear Information System (INIS)

    MACLEAN, G.T.

    1999-01-01

    The settling and compaction of simulated and real nuclear waste slurries were extensively studied. Experiments were carried out with simulated wastes at laboratory and large-scale sizes, and the results compared. A model of settling was derived and a method developed to correlate and scale-up settling data for different slurries and vessel sizes

  19. Sulfur turnover and emissions during storage of cattle slurry

    DEFF Research Database (Denmark)

    Eriksen, Jørgen; Andersen, Astrid J; Poulsen, Henrik Vestergaard

    2012-01-01

    Slurry acidification using sulfuric acid reduces ammonia emissions but also affects sulfur (S) cycling. Emission of sulfur is a source of malodor and reduces the sulfur fertilizer value of the slurry. We investigated the effect of sulfate and methionine amendments, alone or in combination...

  20. Comparison of catalytic ethylene polymerization in slurry and gas phase

    NARCIS (Netherlands)

    Daftaribesheli, Majid

    2009-01-01

    Polyethylene (PE) with the annual consumption of 70 million tones in 2007 is mostly produced in slurry, gas-phase or combination of both processes. This work focuses on a comparison between the slurry and gas phase processes. Why does PE produced in theses two processes can show extremely different

  1. Hydrogen storage in the form of metal hydrides

    Science.gov (United States)

    Zwanziger, M. G.; Santana, C. C.; Santos, S. C.

    1984-01-01

    Reversible reactions between hydrogen and such materials as iron/titanium and magnesium/ nickel alloy may provide a means for storing hydrogen fuel. A demonstration model of an iron/titanium hydride storage bed is described. Hydrogen from the hydride storage bed powers a converted gasoline electric generator.

  2. Pyrophoric behaviour of uranium hydride and uranium powders

    Science.gov (United States)

    Le Guyadec, F.; Génin, X.; Bayle, J. P.; Dugne, O.; Duhart-Barone, A.; Ablitzer, C.

    2010-01-01

    Thermal stability and spontaneous ignition conditions of uranium hydride and uranium metal fine powders have been studied and observed in an original and dedicated experimental device placed inside a glove box under flowing pure argon. Pure uranium hydride powder with low amount of oxide (Oxidation mechanisms are proposed.

  3. Electrocatalytic hydride-forming compounds for rechageable batteries

    NARCIS (Netherlands)

    Notten, P.H.L.; Einerhand, R.E.F.

    1991-01-01

    Non-toxic intermetallic hydride-forming compounds are attractive alternatives to cadmium as the negative electrode materials in the new generation of Ni/metal hydride rechargeable batteries. High exchange currents and discharge efficiencies even at low temperatures can be achieved using highly

  4. Ultra-sonic observation in niobium hydride precipitation

    International Nuclear Information System (INIS)

    Florencio, O.; Pinatti, Dyonisio G.

    1982-01-01

    The hidrogen embrittlement of exothermic ocluders, had been considered as due to applied stress induced hydride precipitates leading to brittle fracture. The results of simultaneous measurements of macroscopic deformation and elastic change due to hydride precipitation, using the ultrasonic pulse-echo technique are showed. THen it was tested the possibility of kinectis precipitation parameters evoluation. (Author) [pt

  5. Creating nanoshell on the surface of titanium hydride bead

    Directory of Open Access Journals (Sweden)

    PAVLENKO Vyacheslav Ivanovich

    2016-12-01

    Full Text Available The article presents data on the modification of titanium hydride bead by creating titanium nanoshell on its surface by ion-plasma vacuum magnetron sputtering. To apply titanium nanoshell on the titanium hydride bead vacuum coating plant of multifunctional nanocomposite coatings QVADRA 500 located in the center of high technology was used. Analysis of the micrographs of the original surface of titanium hydride bead showed that the microstructure of the surface is flat, smooth, in addition the analysis of the microstructure of material surface showed the presence of small porosity, roughness, mainly cavities, as well as shallow longitudinal cracks. The presence of oxide film in titanium hydride prevents the free release of hydrogen and fills some micro-cracks on the surface. Differential thermal analysis of both samples was conducted to determine the thermal stability of the initial titanium hydride bead and bead with applied titanium nanoshell. Hydrogen thermal desorption spectra of the samples of the initial titanium hydride bead and bead with applied titanium nanoshell show different thermal stability of compared materials in the temperature range from 550 to 860о C. Titanium nanoshells applied in this way allows increasing the heat resistance of titanium hydride bead – the temperature of starting decomposition is 695о C and temperature when decomposition finishes is more than 1000о C. Modified in this way titanium hydride bead can be used as a filler in the radiation protective materials used in the construction or upgrading biological protection of nuclear power plants.

  6. Thermal response of a can handling unit (CHU) to a postulated plutonium hydride burn

    International Nuclear Information System (INIS)

    Crea, B.A.; Heard, F.J.

    1998-01-01

    A series of analyses were performed to support the design of the Can Handling Unit (CHU). The subject analyses focused on determining the time to repressurize a subatmospheric storage can containing plutonium metal versus the initial hole size and the transient thermal response to a postulated chemical reaction of 150 grams of plutonium hydride. Limiting the amount of gaseous reactants either by inerting the CHU or using a very small hole size for the initial opening appears to be a viable method of controlling the rate of the exothermic chemical reactions and system temperatures

  7. Bauxite slurry pipeline: start up operation

    Energy Technology Data Exchange (ETDEWEB)

    Othon, Otilio; Babosa, Eder; Edvan, Francisco; Brittes, Geraldo; Melo, Gerson; Janir, Joao; Favacho, Orlando; Leao, Marcos; Farias, Obadias [Vale, Rio de Janeiro, RJ (Brazil); Goncalves, Nilton [Anglo Ferrous Brazil S.A., Rio de Janeiro, RJ (Brazil)

    2009-07-01

    The mine of Miltonia is located in Paragominas-PA, in the north of Brazil. Bauxite slurry pipeline starts at the Mine of Miltonia and finishes in the draining installation of Alunorte refinery at the port of Barcarena-PA, located approximately 244km away from the mine. The pipeline runs over seven cities and passes below four great rivers stream beds. The system was designed for an underground 24 inches OD steel pipe to carry 9.9 million dry metric tonnes per annum (dMTAs) of 50.5% solid concentration bauxite slurry, using only one pumping station. The system is composed by four storage tanks and six piston diaphragm pumps, supplying a flow of 1680 m3/h. There is a cathodic protection system along the pipeline extension to prevent external corrosion and five pressure monitoring stations to control hydraulic conditions, there is also a fiber optic cable interconnection between pump station and terminal station. Pipeline Systems Incorporated (PSI) was the designer and followed the commissioning program of the start up operations. This paper will describe the beginning of the pipeline operations, technical aspects of the project, the operational experiences acquired in these two years, the faced problems and also the future planning. (author)

  8. Preferred hydride growth orientations on oxide-coated gadolinium surfaces

    International Nuclear Information System (INIS)

    Benamar, G.M.; Schweke, D.; Kimmel, G.; Mintz, M.H.

    2012-01-01

    Highlights: ► The preferred hydride growth orientations on gadolinium metal coated by a thin oxide layer are presented. ► A preferred growth of the (1 0 0) h plane of the face centered cubic (FCC) GdH 2 is observed for the hydride spots forming below the oxidation layer. ► A change to the (1 1 1) h plane of the cubic hydride dominates for the hydride's Growth Centers. ► The texture change is attributed to the surface normal compressive stress component exerted by the oxidation layer on the developing hydride. - Abstract: The initial development of hydrides on polycrystalline gadolinium (Gd), as on some other hydride forming metals, is characterized by two sequential steps. The first step involves the rapid formation of a dense pattern of small hydride spots (referred to as the “small family” of hydrides) below the native oxidation layer. The second stage takes place when some of the “small family” nucleants (referred to as “growth centers”, GCs) break the oxide layer, leading to their rapid growth and finally to the massive hydriding of the sample. In the present study, the texture of the two hydride families was studied, by combining X-ray diffraction (XRD) analysis with a microscopic analysis of the hydride, using scanning electron microscopy (SEM) and atomic force microscopy (AFM). It has been observed that for the “small family”, a preferred growth of the (1 0 0) h plane of the cubic GdH 2 takes place, whereas for the GCs, a change to the (1 1 1) h plane of the cubic hydride dominates. These preferred growth orientations were analyzed by their structure relation with the (0 0 .1) m basal plane of the Gd metal. It has been concluded that the above texture change is due to the surface normal compressive stress component exerted by the oxidation overlayer on the developing hydride, preventing the (0 0 .1) m ||(1 1 1) h growth orientation. This stress is relieved upon the rupture of that overlayer and the development of the GCs, leading to

  9. Growth and decomposition of Lithium and Lithium hydride on Nickel

    DEFF Research Database (Denmark)

    Engbæk, Jakob; Nielsen, Gunver; Nielsen, Jane Hvolbæk

    2006-01-01

    In this paper we have investigated the deposition, structure and decomposition of lithium and lithium-hydride films on a nickel substrate. Using surface sensitive techniques it was possible to quantify the deposited Li amount, and to optimize the deposition procedure for synthesizing lithium......-hydride films. By only making thin films of LiH it is possible to study the stability of these hydride layers and compare it directly with the stability of pure Li without having any transport phenomena or adsorbed oxygen to obscure the results. The desorption of metallic lithium takes place at a lower...... temperature than the decomposition of the lithium-hydride, confirming the high stability and sintering problems of lithium-hydride making the storage potential a challenge. (c) 2006 Elsevier B.V. All rights reserved....

  10. Minimizing hydride cracking in zirconium alloys

    International Nuclear Information System (INIS)

    Coleman, C.E.; Cheadle, B.A.; Ambler, J.F.R.; Eadie, R.L.

    1985-01-01

    Zirconium alloy components can fail by hydride cracking if they contain large flaws and are highly stressed. If cracking in such components is suspected, crack growth can be minimized by following two simple operating rules: components should be heated up from at least 30K below any operating temperature above 450K, and when the component requires cooling to room temperature from a high temperature, any tensile stress should be reduced as much and as quickly as is practical during cooling. This paper describes the physical basis for these rules

  11. Tritium immobilization and packaging using metal hydrides

    International Nuclear Information System (INIS)

    Holtslander, W.J.; Yaraskavitch, J.M.

    1981-04-01

    Tritium recovered from CANDU heavy water reactors will have to be packaged and stored in a safe manner. Tritium will be recovered in the elemental form, T 2 . Metal tritides are effective compounds in which to immobilize the tritium as a stable non-reactive solid with a high tritium capacity. The technology necessary to prepare hydrides of suitable metals, such as titanium and zirconium, have been developed and the properties of the prepared materials evaluated. Conceptual designs of packages for containing metal tritides suitable for transportation and long-term storage have been made and initial testing started. (author)

  12. Low-frequency excitations in zirconium hydrides

    International Nuclear Information System (INIS)

    Radulescu, A.; Padureanu, I.; Rapeanu, S.N.; Beldiman, A.; Kozlov, Zh.A.; Semenov, V.A.

    1999-01-01

    The slow inelastic neutron scattering (INS) on ZrH x systems (x = 0.38, 0.52) revealed new excitations located within the energy range 2-10 MeV. Besides the acoustic vibrations specific to α-HCP Zr and γ-FCO Zr hydride the fine structure of these excitations is clearly observed. The origin of the new observed peaks is not very clear but a proton tunneling or a resonance effect in α-Zr lattice could be taken into account

  13. Characterization methodology for re-using marble slurry in industrial applications

    Science.gov (United States)

    Marras, Graziella; Careddu, Nicola; Peretti, Roberto; Bortolussi, Augusto

    2017-04-01

    In the effort towards waste minimization and circular economy, natural stone waste is one of the foremost parameter to turn scientific community attention. At this time, calcium carbonate has a great importance in industrial fields and currently there is the necessity of appreciate the potential value of marble waste and convert it into marketable products. A large amount of residues is produced in ornamental stone sector with different dimension and particle size. The research focused on marble slurry, recovered at the end of the treatment plant in the filter-press section. The aim of this paper is to propose a defined way to characterize marble slurry, primarily composed of micronized particles, in order to obtain useful data to make a comparison with market specifications. In particular the proposed characterization methodology follows the indicated steps: Leaching test (TCLP) - Grain size distribution and bulk density - Mineralogical analyses - X-Ray diffraction - Chemical analysis - Loss on ignition - SEM determination - Colorimetric and bright analysis. Marble slurry samples, collected by different dimension stone treatment plants in Orosei marble district (Sardinia - Italy), were analyzed by physical, mineralogical and chemical determinations and the obtained data were evaluated for compatibility with the CaCO3 specifications required by a definite industrial sector, seeing as how CaCO3 product specifications vary depending on the utilization. The importance of this investigation is to characterize completely the "waste" that must apply for further uses and to identify the feasibility to substitute marketable micronized CaCO3 with marble slurry. Further goal is to enhance the environmental advantages of re-using stone waste by reducing marble waste landfills and by applying raw material substitution, in accordance with regulatory requirements, thus pursuing the objective to convert natural stone waste into by-product with a renewed environmental and economic

  14. Nanoindentation measurements of the mechanical properties of zirconium matrix and hydrides in unirradiated pre-hydrided nuclear fuel cladding

    International Nuclear Information System (INIS)

    Rico, A.; Martin-Rengel, M.A.; Ruiz-Hervias, J.; Rodriguez, J.; Gomez-Sanchez, F.J.

    2014-01-01

    It is well known that the mechanical properties of the nuclear fuel cladding may be affected by the presence of hydrides. The average mechanical properties of hydrided cladding have been extensively investigated from a macroscopic point of view. In addition, the mechanical and fracture properties of bulk hydride samples fabricated from zirconium plates have also been reported. In this paper, Young’s modulus, hardness and yield stress are measured for each phase, namely zirconium hydrides and matrix, of pre-hydrided nuclear fuel cladding. To this end, nanoindentation tests were performed on ZIRLO samples in as-received state, on a hydride blister and in samples with 150 and 1200 ppm of hydrogen homogeneously distributed along the hoop direction of the cladding. The results show that the measured mechanical properties of the zirconium hydrides and ZIRLO matrix (Young’s modulus, hardness and yield stress) are rather similar. From the experimental data, the hydride volume fraction in the cladding samples with 150 and 1200 ppm was estimated and the average mechanical properties were calculated by means of the rule of mixtures. These values were compared with those obtained from ring compression tests. Good agreement between the results obtained by both methods was found

  15. Improved Fischer-Tropsch Slurry Reactors

    International Nuclear Information System (INIS)

    Lucero, Andrew

    2009-01-01

    The conversion of synthesis gas to hydrocarbons or alcohols involves highly exothermic reactions. Temperature control is a critical issue in these reactors for a number of reasons. Runaway reactions can be a serious safety issue, even raising the possibility of an explosion. Catalyst deactivation rates tend to increase with temperature, particularly of there are hot spots in the reactor. For alcohol synthesis, temperature control is essential because it has a large effect on the selectivity of the catalysts toward desired products. For example, for molybdenum disulfide catalysts unwanted side products such as methane, ethane, and propane are produced in much greater quantities if the temperature increases outside an ideal range. Slurry reactors are widely regarded as an efficient design for these reactions. In a slurry reactor a solid catalyst is suspended in an inert hydrocarbon liquid, synthesis gas is sparged into the bottom of the reactor, un-reacted synthesis gas and light boiling range products are removed as a gas stream, and heavy boiling range products are removed as a liquid stream. This configuration has several positive effects for synthesis gas reactions including: essentially isothermal operation, small catalyst particles to reduce heat and mass transfer effects, capability to remove heat rapidly through liquid vaporization, and improved flexibility on catalyst design through physical mixtures in addition to use of compositions that cannot be pelletized. Disadvantages include additional mass transfer resistance, potential for significant back-mixing on both the liquid and gas phases, and bubble coalescence. In 2001 a multiyear project was proposed to develop improved FT slurry reactors. The planned focus of the work was to improve the reactors by improving mass transfer while considering heat transfer issues. During the first year of the project the work was started and several concepts were developed to prepare for bench-scale testing. Power

  16. Application of acoustic emission to hydride cracking

    International Nuclear Information System (INIS)

    Sagat, S.; Ambler, J.F.R.; Coleman, C.E.

    1986-07-01

    Acoustic emission has been used for over a decade to study delayed hydride cracking (DHC) in zirconium alloys. At first acoustic emission was used primarily to detect the onset of DHC. This was possible because DHC was accompanied by very little plastic deformation of the material and furthermore the amplitudes of the acoustic pulses produced during cracking of the brittle hydride phase were much larger than those from dislocation motion and twinning. Acoustic emission was also used for measuring crack growth when it was found that for a suitable amplitude threshold, the total number of acoustic emission counts was linearly related to the cracked area. Once the proportionality constant was established, the acoustic counts could be converted to the crack length. Now the proportionality between the count rate and the crack growth rate is used to provide feedback between the crack length and the applied load, using computer technology. In such a system, the stress at the crack tip can be maintained constant during the test by adjusting the applied load as the crack progresses, or it can be changed in a predetermined manner, for example, to measure the threshold stress for cracking

  17. NATO Advanced Study Institute on Metal Hydrides

    CERN Document Server

    1981-01-01

    In the last five years, the study of metal hydrides has ex­ panded enormously due to the potential technological importance of this class of materials in hydrogen based energy conversion schemes. The scope of this activity has been worldwide among the industrially advanced nations. There has been a consensus among researchers in both fundamental and applied areas that a more basic understanding of the properties of metal/hydrogen syster;,s is required in order to provide a rational basis for the selection of materials for specific applications. The current worldwide need for and interest in research in metal hydrides indicated the timeliness of an Advanced Study Insti­ tute to provide an in-depth view of the field for those active in its various aspects. The inclusion of speakers from non-NATO coun­ tries provided the opportunity for cross-fertilization of ideas for future research. While the emphasis of the Institute was on basic properties, there was a conscious effort to stimulate interest in the applic...

  18. Tailoring Thermodynamics and Kinetics for Hydrogen Storage in Complex Hydrides towards Applications.

    Science.gov (United States)

    Liu, Yongfeng; Yang, Yaxiong; Gao, Mingxia; Pan, Hongge

    2016-02-01

    Solid-state hydrogen storage using various materials is expected to provide the ultimate solution for safe and efficient on-board storage. Complex hydrides have attracted increasing attention over the past two decades due to their high gravimetric and volumetric hydrogen densities. In this account, we review studies from our lab on tailoring the thermodynamics and kinetics for hydrogen storage in complex hydrides, including metal alanates, borohydrides and amides. By changing the material composition and structure, developing feasible preparation methods, doping high-performance catalysts, optimizing multifunctional additives, creating nanostructures and understanding the interaction mechanisms with hydrogen, the operating temperatures for hydrogen storage in metal amides, alanates and borohydrides are remarkably reduced. This temperature reduction is associated with enhanced reaction kinetics and improved reversibility. The examples discussed in this review are expected to provide new inspiration for the development of complex hydrides with high hydrogen capacity and appropriate thermodynamics and kinetics for hydrogen storage. © 2015 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Mechanism of n-butane hydrogenolysis promoted by Ta-hydrides supported on silica

    KAUST Repository

    Pasha, Farhan Ahmad

    2014-06-06

    The mechanism of hydrogenolysis of alkanes, promoted by Ta-hydrides supported on silica via 2 ≡ Si-O- bonds, has been studied with a density functional theory (DFT) approach. Our study suggests that the initial monohydride (≡ Si-O-)2Ta(III)H is rapidly trapped by molecular hydrogen to form the more stable tris-hydride (≡ Si-O-) 2Ta(V)H3. Loading of n-butane to the Ta-center occurs through C-H activation concerted with elimination of molecular hydrogen (σ-bond metathesis). Once the Ta-alkyl species is formed, the C-C activation step corresponds to a β-alkyl transfer to the metal with elimination of an olefin. According to these calculations, an α-alkyl transfer to the metal to form a Ta-carbene species is of higher energy. The olefins formed during the C-C activation step can be rapidly hydrogenated by both mono- and tris-Ta-hydride species, making the overall process of alkane cracking thermodynamically favored. © 2014 American Chemical Society.

  20. Reduction of Methane Emission during Slurry Storage by the Addition of Effective Microorganisms and Excessive Carbon Source from Brewing Sugar.

    Science.gov (United States)

    Bastami, Mohd Saufi B; Jones, Davey L; Chadwick, David R

    2016-11-01

    Storing livestock manure is the primary stage of manure management where microbial processes and chemical reactions result in the release of methane (CH), nitrous oxide (NO), ammonia (NH), and carbon dioxide (CO). This study examined the reduction of CH emissions from slurry storage under two temperatures (cool [10°C] and warm [30°C]) when a glucose-rich substrate (brewing sugar) and activated effective microorganisms were applied at 10% (w/w) and 5% (v/w), respectively. Brewing sugar addition influenced microbial anaerobic respiration, resulting in a reduction of slurry pH to <5.0, through "self-acidification" caused by lactic acid production. Subsequently, CH emissions were significantly reduced by 87 and 99% in the cool and warm environments, respectively. The effective microorganism treatment did not change the chemical characteristics of the slurry but reduced CH emissions by 17 and 27% ( < 0.05) in the cool and warm environments, respectively. These results suggest that self-acidification after addition of a carbon source may be a promising alternative to slurry acidification using concentrated acids. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. Testing of In-Line Slurry Monitors and Pulsair Mixers with Radioactive Slurries

    Energy Technology Data Exchange (ETDEWEB)

    Hylton, T.D.; Bayne, C.K.

    1999-08-01

    Three in-line slurry monitoring instruments were demonstrated, tested, and evaluated for their capability to determine the transport properties of radioactive slurries. The instruments included the Endress + Hauser Promass 63M Coriolis meter for measuring density, the Lasentec M600P for measuring particle size distribution, and a prototype ultrasonic monitor that was developed by Argonne National Laboratory for measuring suspended solids concentration. In addition, the power consumption of the recirculation pump was monitored to determine whether this parameter could be used as a tool for in-line slurry monitoring. The Promass 63M and the M600P were also evaluated as potential indicators of suspended solids concentration. In order to use the Promass 63M as a suspended solids monitor, the densities of the fluid phase and the dry solid particle phase must be known. In addition, the fluid phase density and the dry solids density must remain constant, as any change will affect the correlation between the slurry density and the suspended solids concentration. For the M600P, the particle size distribution would need to remain relatively constant. These instruments were demonstrated and tested at the Gunite and Associated Tanks Remediation Project at the Oak Ridge National Laboratory. The testing of the instruments was conducted in parallel with the testing of a Pulsair mixing system, which was used to mix the contents of the selected tank. A total of six tests were performed. A submersible pump was positioned at two depths, while the Pulsair system was operated at three mixing rates.

  2. Ice slurries; Les coulis de glace

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The safety and environmental problems linked with the use of refrigerants (toxicity, flammability, ozone layer, greenhouse effect) are the object of numerous research works in order to reduce their harmful impact in the case of accidental situation. The use of 'coldness carriers' is particularly justified in the case of industrial refrigerating facilities involving long loops and important quantities of refrigerating fluids. The use of single-phase 'coldness carriers' is a very old technique which encounters a revival today with researches in progress about the use of two-phase (liquid-solid) compounds named ice-slurries. This book takes stock of the status of this research work in a practical and exhaustive way. (J.S.)

  3. Regulatory controls and slurry fracture injection

    International Nuclear Information System (INIS)

    Dusseault, M. B.; Bilak, R. A.

    1997-01-01

    The technological and regulatory framework necessary for the safe operation of solid waste disposal using slurry fracture injection (SFI) in Saskatchewan and Alberta was studied. Seven current SFI sites were used as the source of experience. Regular audits of volumes, continuous pressure recording, careful deformation monitoring and analysis, and repeated evaluation of reservoir properties were considered to be the essential features. In the case of toxic wastes, microseismic monitoring and regular well interference or tracer tests might be additional measures used to increase confidence in the containment method. Given the recent introduction of SFI technology, guarding against over-regulation was recommended to allow SFI to operate under the most effective operating conditions, and to preserve its attractiveness as an environmentally attractive and safe waste disposal alternative. 5 refs., 3 tabs., 4 figs

  4. Drilling mud and cement slurry rheology manual

    Energy Technology Data Exchange (ETDEWEB)

    This book is not primarily concerned with theory. Its basic approach is practical. It has attempted to present a logical treatment which will be easy to apply in practice. As a result, certain computing methods were omitted, and precision sometimes has to be sacrificed to simplicity. However, no apology is made for the use of such approximations; in fact, any attempt at rigor would be doomed to failure, in view of the many inherent factors which do not lend themselves to quantitative treatment. Chapter 1: deals with fundamental concepts. Chapter 2: refers to the general principles involved in determining rheological parameters of drilling fluids and cement slurries. Chapter 3: relates to practical methods for using the results obtained in the first two Chapters, in units employed on the worksite. It is primarily intended for technicians called upon to make ''hydraulic'' computations during drilling. Chapter 4: contains several examples.

  5. Hydrodynamic models for slurry bubble column reactors

    Energy Technology Data Exchange (ETDEWEB)

    Gidaspow, D. [IIT Center, Chicago, IL (United States)

    1995-12-31

    The objective of this investigation is to convert a {open_quotes}learning gas-solid-liquid{close_quotes} fluidization model into a predictive design model. This model is capable of predicting local gas, liquid and solids hold-ups and the basic flow regimes: the uniform bubbling, the industrially practical churn-turbulent (bubble coalescence) and the slugging regimes. Current reactor models incorrectly assume that the gas and the particle hold-ups (volume fractions) are uniform in the reactor. They must be given in terms of empirical correlations determined under conditions that radically differ from reactor operation. In the proposed hydrodynamic approach these hold-ups are computed from separate phase momentum balances. Furthermore, the kinetic theory approach computes the high slurry viscosities from collisions of the catalyst particles. Thus particle rheology is not an input into the model.

  6. PCB dechlorination in anaerobic soil slurry reactors

    International Nuclear Information System (INIS)

    Klasson, K.T.; Evans, B.S.

    1993-01-01

    Many industrial locations, including the US Department of Energy's, have identified needs for treatment of polychlorinated biphenyl (PCB) wastes and remediation of PCB-contaminated sites. Biodegradation of PCBs is a potentially effective technology for the treatment of PCB-contaminated soils and sludges, including mixed wastes; however, a practical remediation technology has not yet been demonstrated. In laboratory experiments, soil slurry bioreactors inoculated with microorganisms extracted from PCB-contaminated sediments from the Hudson River have been used to obtain anaerobic dechlorination of PCBS. The onset of dechlorination activity can be accelerated by addition of nutritional amendments and inducers. After 15 weeks of incubation with PCB-contaminated soil and nutrient solution, dechlorination has been observed under several working conditions. The best results show that the average chlorine content steadily dropped from 4.3 to 3.5 chlorines per biphenyl over a 15-week period

  7. Alloys for hydrogen storage in nickel/hydrogen and nickel/metal hydride batteries

    Science.gov (United States)

    Anani, Anaba; Visintin, Arnaldo; Petrov, Konstantin; Srinivasan, Supramaniam; Reilly, James J.; Johnson, John R.; Schwarz, Ricardo B.; Desch, Paul B.

    1993-01-01

    Since 1990, there has been an ongoing collaboration among the authors in the three laboratories to (1) prepare alloys of the AB(sub 5) and AB(sub 2) types, using arc-melting/annealing and mechanical alloying/annealing techniques; (2) examine their physico-chemical characteristics (morphology, composition); (3) determine the hydrogen absorption/desorption behavior (pressure-composition isotherms as a function of temperature); and (4) evaluate their performance characteristics as hydride electrodes (charge/discharge, capacity retention, cycle life, high rate capability). The work carried out on representative AB(sub 5) and AB(sub 2) type modified alloys (by partial substitution or with small additives of other elements) is presented. The purpose of the modification was to optimize the thermodynamics and kinetics of the hydriding/dehydriding reactions and enhance the stabilities of the alloys for the desired battery applications. The results of our collaboration, to date, demonstrate that (1) alloys prepared by arc melting/annealing and mechanical alloying/annealing techniques exhibit similar morphology, composition and hydriding/dehydriding characteristics; (2) alloys with the appropriate small amounts of substituent or additive elements: (1) retain the single phase structure, (2) improve the hydriding/dehydriding reactions for the battery applications, and (3) enhance the stability in the battery environment; and (3) the AB(sub 2) type alloys exhibit higher energy densities than the AB(sub 5) type alloys but the state-of-the-art, commercialized batteries are predominantly manufactured using Ab(sub 5) type alloys.

  8. Toxicity Evaluation of Pig Slurry Using Luminescent Bacteria and Zebrafish

    Directory of Open Access Journals (Sweden)

    Wenyan Chen

    2014-07-01

    Full Text Available Biogas slurry has become a serious pollution problem and anaerobic digestion is widely applied to pig manure treatment for environmental protection and energy recovery. To evaluate environmental risk of the emission of biogas slurry, luminescent bacteria (Vibrio fischeri, larvae and embryos of zebrafish (Danio rerio were used to detect the acute and development toxicity of digested and post-treated slurry. Then the ability of treatment process was evaluated. The results showed that digested slurry displayed strong toxicity to both zebrafish and luminescent bacteria, while the EC50 for luminescent bacteria and the LC50 for larvae were only 6.81% (v/v and 1.95% (v/v respectively, and embryonic development was inhibited at just 1% (v/v. Slurry still maintained a high level of toxicity although it had been treated by membrane bioreactor (MBR, while the LC50 of larvae was 75.23% (v/v and there was a little effect on the development of embryos and V. fischeri; the results also revealed that the zebrafish larvae are more sensitive than embryos and luminescent bacteria to pig slurry. Finally, we also found the toxicity removal rate was higher than 90% after the treatment of MBR according to toxicity tests. In conclusion, further treatment should be used in pig slurry disposal or reused of final effluent.

  9. Enhanced conversion efficiency of dye-sensitized solar cells using a CNT-incorporated TiO2 slurry-based photoanode

    Directory of Open Access Journals (Sweden)

    Jiaoping Cai

    2015-02-01

    Full Text Available A new titanium dioxide (TiO2 slurry formulation is herein reported for the fabrication of TiO2 photoanode for use in dye-sensitized solar cells (DSSCs. The prepared TiO2 photoanode featured a highly uniform mesoporous structure with well-dispersed TiO2 nanoparticles. The energy conversion efficiency of the resulting TiO2 slurry-based DSSC was ∼63% higher than that achieved by a DSSC prepared using a commercial TiO2 slurry. Subsequently, the incorporation of acid-treated multi-walled carbon nanotubes (CNTs into the TiO2 slurry was examined. More specifically, the effect of varying the concentration of the CNTs in this slurry on the performance of the resulting DSSCs was studied. The chemical state of the CNTs-incorporated TiO2 photoanode was investigated by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. A high energy conversion efficiency of 6.23% was obtained at an optimum CNT concentration of ∼0.06 wt.%. The obtained efficiency corresponds to a 63% enhancement when compared with that obtained from a DSSC based on a commercial TiO2 slurry. The higher efficiency was attributed to the improvement in the collection and transport of excited electrons in the presence of the CNTs.

  10. Enhanced conversion efficiency of dye-sensitized solar cells using a CNT-incorporated TiO2 slurry-based photoanode

    Science.gov (United States)

    Cai, Jiaoping; Chen, Zexiang; Li, Jun; Wang, Yan; Xiang, Dong; Zhang, Jijun; Li, Hai

    2015-02-01

    A new titanium dioxide (TiO2) slurry formulation is herein reported for the fabrication of TiO2 photoanode for use in dye-sensitized solar cells (DSSCs). The prepared TiO2 photoanode featured a highly uniform mesoporous structure with well-dispersed TiO2 nanoparticles. The energy conversion efficiency of the resulting TiO2 slurry-based DSSC was ˜63% higher than that achieved by a DSSC prepared using a commercial TiO2 slurry. Subsequently, the incorporation of acid-treated multi-walled carbon nanotubes (CNTs) into the TiO2 slurry was examined. More specifically, the effect of varying the concentration of the CNTs in this slurry on the performance of the resulting DSSCs was studied. The chemical state of the CNTs-incorporated TiO2 photoanode was investigated by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. A high energy conversion efficiency of 6.23% was obtained at an optimum CNT concentration of ˜0.06 wt.%. The obtained efficiency corresponds to a 63% enhancement when compared with that obtained from a DSSC based on a commercial TiO2 slurry. The higher efficiency was attributed to the improvement in the collection and transport of excited electrons in the presence of the CNTs.

  11. ANALYSIS OF VENTING OF A RESIN SLURRY

    Energy Technology Data Exchange (ETDEWEB)

    Laurinat, J.; Hensel, S.

    2012-03-27

    A resin slurry venting analysis was conducted to address safety issues associated with overpressurization of ion exchange columns used in the Purex process at the Savannah River Site (SRS). If flow to these columns were inadvertently interrupted, an exothermic runaway reaction could occur between the ion exchange resin and the nitric acid used in the feed stream. The nitric acid-resin reaction generates significant quantities of noncondensable gases, which would pressurize the column. To prevent the column from rupturing during such events, rupture disks are installed on the column vent lines. The venting analysis models accelerating rate calorimeter (ARC) tests and data from tests that were performed in a vented test vessel with a rupture disk. The tests showed that the pressure inside the test vessel continued to increase after the rupture disk opened, though at a slower rate than prior to the rupture. Calculated maximum discharge rates for the resin venting tests exceeded the measured rates of gas generation, so the vent size was sufficient to relieve the pressure in the test vessel if the vent flow rate was constant. The increase in the vessel pressure is modeled as a transient phenomenon associated with expansion of the resin slurry/gas mixture upon rupture of the disk. It is postulated that the maximum pressure at the end of this expansion is limited by energy minimization to approximately 1.5 times the rupture disk burst pressure. The magnitude of this pressure increase is consistent with the measured pressure transients. The results of this analysis demonstrate the need to allow for a margin between the design pressure and the rupture disk burst pressure in similar applications.

  12. Isotope exchange between gaseous hydrogen and uranium hydride powder

    International Nuclear Information System (INIS)

    Shugard, Andrew D.; Buffleben, George M.; Johnson, Terry A.; Robinson, David B.

    2014-01-01

    Highlights: • Isotope exchange between hydrogen gas and uranium hydride powder can be rapid and reversible. • Gas–solid exchange rate is controlled by transport within ∼0.7 μm hydride particles. • Gas chromatographic separation of hydrogen isotopes using uranium hydride is feasible. - Abstract: Isotope exchange between gaseous hydrogen and solid uranium hydride has been studied by flowing hydrogen (deuterium) gas through packed powder beds of uranium deuteride (hydride). We used a residual gas analyzer system to perform real-time analysis of the effluent gas composition. We also developed an exchange and transport model and, by fitting it to the experimental data, extracted kinetic parameters for the isotope exchange reaction. Our results suggest that, from approximately 70 to 700 kPa and 25 to 400 °C, the gas-to-solid exchange rate is controlled by hydrogen and deuterium transport within the ∼0.7 μm diameter uranium hydride particles. We use our kinetic parameters to show that gas chromatographic separation of hydrogen and deuterium using uranium hydride could be feasible

  13. A study of stress reorientation of hydrides in zircaloy

    Energy Technology Data Exchange (ETDEWEB)

    Yourong, Jiang; Bangxin, Zhou [Nuclear Power Inst. of China, Chengdu, SC (China)

    1994-10-01

    Under the conditions of circumferential tensile stress from 70 to 180 MPa for Zircaloy tubes or the tensile stress from 55 to 180 MPa for Zircaloy-4 plates and temperature cycling between 150 and 400 degree C, the effects of stress and the number of temperature cycling on hydride reorientation in Zircaloy-4 tubes and plates and Zircaloy-2 tubes containing about 220 {mu}g/g hydrogen have been investigated. With the increase of stress and/or the number of temperature cycling, the level of hydride reorientation increases. When hydride reorientation takes place, there is a threshold stress concerned with the number of temperature cycling. Below the threshold stress, hydride reorientation is not obvious. When applied stress is higher than the threshold stress, the level of hydride reorientation increases with the increase of stress and the number of temperature cycling. Hydride reorientation in Zircaloy-4 tubes develops gradually from the outer surface to inner surface. It might be related to the difference of texture between outer surface and inner surface. The threshold stress is affected by both the texture and the value of B. So controlling texture could still restrict hydride reorientation under tensile stress.

  14. Corrosion studies of carbon steel under impinging jets of simulated slurries of neutralized current acid waste (NCAW) and neutralized cladding removal waste (NCRW)

    International Nuclear Information System (INIS)

    Smith, H.D.; Elmore, M.R.

    1992-01-01

    Plans for the disposal of radioactive liquid and solid wastes presently stored in double-shell tanks at the Hanford Site call for retrieval and processing of the waste to create forms suitable for permanent disposal. Waste will be retrieved from a tank using a submerged slurry pump in conjunction with one or more rotating slurry jet mixer pumps. Pacific Northwest Laboratory (PNL) has conducted tests using simulated waste slurries to assess the effects of a impinging slurry jet on the corrosion rate of the tank wall and floor, an action that could potentially compromise the tank's structural integrity. Corrosion processes were investigated on a laboratory scale with a simulated neutralized cladding removal waste (NCRW) slurry and in a subsequent test with simulated neutralized current acid waste (NCAW) slurry. The test slurries simulated the actual NCRW and NCAW both chemically and physically. The tests simulated those conditions expected to exist in the respective double-shell tanks during waste retrieval operations. Results of both tests indicate that, because of the action of the mixer pump slurry jets, the waste retrieval operations proposed for NCAW and NCRW will moderately accelerate corrosion of the tank wall and floor. Based on the corrosion of initially unoxidized test specimens, and the removal of corrosion products from those specimens, the maximum time-averaged corrosion rates of carbon steel in both waste simulants for the length of the test was ∼4 mil/yr. The protective oxide layer that exists in each storage tank is expected to inhibit corrosion of the carbon steel

  15. Hydrogen storage in metal hydrides and complex hydrides; Wasserstoffspeicherung in Metall- und komplexen Hydriden - Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Bielmann, M.; Zuettel, A.

    2007-07-01

    This final report for the Swiss Federal Office of Energy (SFOE), reports on work done in 2007 at the Swiss Federal Laboratories for Materials Science and Technology EMPA on the storage of hydrogen in metal hydrides and complex hydrides. In particular, the use of tetrahydroborates is noted. The potential of this class of materials is stressed. The structures at room-temperature were examined using neutron and X-ray diffraction methods. Thermodynamic methods helped determine the thermodynamic stability of the materials. Also, a complete energy diagram for the materials was developed. The use of silicon oxide to reduce activation energy and its catalytic effects are discussed. The challenges placed by desorption mechanisms are noted. The authors note that reversibility is basically proven.

  16. Dealloyed Ruthenium Film Catalysts for Hydrogen Generation from Chemical Hydrides

    Directory of Open Access Journals (Sweden)

    Ramis B. Serin

    2017-07-01

    Full Text Available Thin-film ruthenium (Ru and copper (Cu binary alloys have been prepared on a Teflon™ backing layer by cosputtering of the precious and nonprecious metals, respectively. Alloys were then selectively dealloyed by sulfuric acid as an etchant, and their hydrogen generation catalysts performances were evaluated. Sputtering time and power of Cu atoms have been varied in order to tailor the hydrogen generation performances. Similarly, dealloying time and the sulfuric acid concentration have also been altered to tune the morphologies of the resulted films. A maximum hydrogen generation rate of 35 mL min−1 was achieved when Cu sputtering power and time were 200 W and 60 min and while acid concentration and dealloying time were 18 M and 90 min, respectively. It has also been demonstrated that the Ru content in the alloy after dealloying gradually increased with the increasing the sputtering power of Cu. After 90 min dealloying, the Ru to Cu ratio increased to about 190 times that of bare alloy. This is the key issue for observing higher catalytic activity. Interestingly, we have also presented template-free nanoforest-like structure formation within the context of one-step alloying and dealloying used in this study. Last but not least, the long-time hydrogen generation performances of the catalysts system have also been evaluated along 3600 min. During the first 600 min, the catalytic activity was quite stable, while about 24% of the catalytic activity decayed after 3000 min, which still makes these systems available for the development of robust catalyst systems in the area of hydrogen generation.

  17. Development of Syringe/Bottle Hybrids for Sampling Slurries

    International Nuclear Information System (INIS)

    Coleman, C.J.

    1998-01-01

    A convenient and effective sample bottle system based on simple modifications of disposable plastic syringes and bottles has been devised and tested for slurry samples. Syringe/ bottle hybrids (hereafter referred to as syringe bottles) have the convenience of regular flat-bottom bottles with screw cap closures. In addition, the syringe imparts a sliding and adjustable bottom to the bottle that forces the entire contents from the bottle. The system was designed especially to collect samples for high temperature work-ups of DWPF slurry samples. The syringe bottles together with fixed-bottom sample vial inserts would provide the DWPF with convenient and reliable methods for dealing with slurry samples

  18. Evaluation of plant available nitrogen in concentrated pig slurry

    International Nuclear Information System (INIS)

    Ramirez, M.; Comas, J.; Pujola, M.

    2009-01-01

    In Northeast Spin the expansion of the pig industry has brought as a result the production of vast amounts of pig slurry that exceeds field crops fertilization needs and consequently has contributed to the environmental deterioration of the region particularly ground water with NO 3 pollution. Under such circumstances, it is needed to treat and/or export pig slurry. During the last year the implantation of cogeneration plants that take advantage of the surplus of energy to produce concentrate pig slurry by water evaporation that could easily transported. (Author)

  19. Interactions between Soil Texture and Placement of Dairy Slurry Application

    DEFF Research Database (Denmark)

    Glæsner, Nadia; Kjærgaard, Charlotte; Rubæk, Gitte Holton

    2011-01-01

    soils. We compared leaching of slurry-applied bromide through intact soil columns (20 cm diam., 20 cm high) of differing textures following surface application or injection of slurry. The volumetric fraction of soil pores >30 μm ranged from 43% in a loamy sand to 28% in a sandy loam and 15% in a loam...... physical protection against leaching of bromide was reflected by 60.2% of the bromide tracer was recovered in the effluent after injection, compared with 80.6% recovery after surface application. No effect of slurry injection was observed in the loamy sand and sandy loam soils. Our findings point to soil...

  20. Use of radiation-induced polymers in cement slurries

    International Nuclear Information System (INIS)

    Knight, B.L.; Rhudy, J.S.; Gogarty, W.B.

    1976-01-01

    Water loss from cement slurries is reduced by incorporating within a cement slurry a polymer obtained as a product of radiation-induced polymerization of acrylamide and/or methacrylamide and acrylic acid, methacrylic acid, and/or alkali metal salts thereof. The polymerization is preferably carried out in 10-60 percent aqueous monomer solution with gamma radiation. The aqueous monomer solution preferably contains 25-99 percent acrylamide and 75-1 percent sodium acrylate. The polymer can be present in concentration of about 0.001 to about 3.0 weight percent, based on the aqueous phase of the slurry

  1. Complex metal hydrides for hydrogen, thermal and electrochemical energy storage

    DEFF Research Database (Denmark)

    Møller, Kasper T.; Sheppard, Drew; Ravnsbæk, Dorthe B.

    2017-01-01

    field. This review illustrates that complex metal hydrides may store hydrogen in the solid state, act as novel battery materials, both as electrolytes and electrode materials, or store solar heat in a more efficient manner as compared to traditional heat storage materials. Furthermore, it is highlighted...... how complex metal hydrides may act in an integrated setup with a fuel cell. This review focuses on the unique properties of light element complex metal hydrides mainly based on boron, nitrogen and aluminum, e.g., metal borohydrides and metal alanates. Our hope is that this review can provide new...

  2. Finite difference program for calculating hydride bed wall temperature profiles

    International Nuclear Information System (INIS)

    Klein, J.E.

    1992-01-01

    A QuickBASIC finite difference program was written for calculating one dimensional temperature profiles in up to two media with flat, cylindrical, or spherical geometries. The development of the program was motivated by the need to calculate maximum temperature differences across the walls of the Tritium metal hydrides beds for thermal fatigue analysis. The purpose of this report is to document the equations and the computer program used to calculate transient wall temperatures in stainless steel hydride vessels. The development of the computer code was motivated by the need to calculate maximum temperature differences across the walls of the hydrides beds in the Tritium Facility for thermal fatigue analysis

  3. Investigation process of alcoholysis of hydride aluminium-adobe

    International Nuclear Information System (INIS)

    Numanov, M.I.; Normatov, I.Sh.; Mirsaidov, U.M.

    2001-01-01

    Considering of that process of acid treatment of aluminium-adobe hydride realizes in the ethyl alcohol media it was necessary study the process of alcoholysis of AlH 3 and aluminium additives. In the end of article authors became to conclusion that deficiency of spontaneous alcoholysis of AlH 3 in adobe caused by protective action of fiber; solvate ability of LiCl and alkoxy aluminium hydride of lithium-LiCl·CO 2 H 5 OH, Li Al(OC 2 H 5 ) 4 ·nC 2 H 5 OH decreasing the expectancy of responding of alcohol with aluminium hydride

  4. COMPUTATIONAL AND EXPERIMENTAL MODELING OF THREE-PHASE SLURRY-BUBBLE COLUMN REACTOR

    Energy Technology Data Exchange (ETDEWEB)

    Isaac K. Gamwo; Dimitri Gidaspow

    1999-09-01

    Considerable progress has been achieved in understanding three-phase reactors from the point of view of kinetic theory. In a paper in press for publication in Chemical Engineering Science (Wu and Gidaspow, 1999) we have obtained a complete numerical solution of bubble column reactors. In view of the complexity of the simulation a better understanding of the processes using simplified analytical solutions is required. Such analytical solutions are presented in the attached paper, Large Scale Oscillations or Gravity Waves in Risers and Bubbling Beds. This paper presents analytical solutions for bubbling frequencies and standing wave flow patterns. The flow patterns in operating slurry bubble column reactors are not optimum. They involve upflow in the center and downflow at the walls. It may be possible to control flow patterns by proper redistribution of heat exchangers in slurry bubble column reactors. We also believe that the catalyst size in operating slurry bubble column reactors is not optimum. To obtain an optimum size we are following up on the observation of George Cody of Exxon who reported a maximum granular temperature (random particle kinetic energy) for a particle size of 90 microns. The attached paper, Turbulence of Particles in a CFB and Slurry Bubble Columns Using Kinetic Theory, supports George Cody's observations. However, our explanation for the existence of the maximum in granular temperature differs from that proposed by George Cody. Further computer simulations and experiments involving measurements of granular temperature are needed to obtain a sound theoretical explanation for the possible existence of an optimum catalyst size.

  5. Development of low angle grain boundaries in lightly deformed superconducting niobium and their influence on hydride distribution and flux perturbation

    Science.gov (United States)

    Sung, Z.-H.; Wang, M.; Polyanskii, A. A.; Santosh, C.; Balachandran, S.; Compton, C.; Larbalestier, D. C.; Bieler, T. R.; Lee, P. J.

    2017-05-01

    This study shows that low angle grain boundaries (LAGBs) can be created by small 5% strains in high purity (residual resistivity ratio ≥ 200) superconducting radio frequency (SRF)-grade single crystalline niobium (Nb) and that these boundaries act as hydrogen traps as indicated by the distribution of niobium hydrides (Nb1-xHx). Nb1-xHx is detrimental to SRF Nb cavities due to its normal conducting properties at cavity operating temperatures. By designing a single crystal tensile sample extracted from a large grain (>5 cm) Nb ingot slice for preferred slip on one slip plane, LAGBs and dense dislocation boundaries developed. With chemical surface treatments following standard SRF cavity fabrication practice, Nb1-xHx phases were densely precipitated at the LAGBs upon cryogenic cooling (8-10 K/min). Micro-crystallographic analysis confirmed heterogeneous hydride precipitation, which included significant hydrogen atom accumulation in LAGBs. Magneto-optical imaging analysis showed that these sites can then act as sites for both premature flux penetration and eventually flux trapping. However, this hydrogen related degradation at LAGBs did not completely disappear even after an 800 °C/2 h anneal typically used for hydrogen removal in SRF Nb cavities. These findings suggest that hydride precipitation at an LAGB is facilitated by a non-equilibrium concentration of vacancy-hydrogen (H) complexes aided by mechanical deformation and the hydride phase interferes with the recovery process under 800 °C annealing.

  6. Determination of hydrogen in zirconium hydride and uranium-zirconium hydride by inert gas exraction-gravimetric method

    International Nuclear Information System (INIS)

    Hoshino, Akira; Iso, Shuichi

    1976-01-01

    An inert gas extraction-gravimetric method has been applied to the determination of hydrogen in zirconium hydride and uranium-zirconium hydride which are used as neutron moderator and fuel of nuclear safety research reactor (NSRR), respectively. The sample in a graphite-enclosed quartz crucible is heated inductively to 1200 0 C for 20 min in a helium stream. Hydrogen liberated from the sample is oxidized to water by copper(I) oxide-copper(II) oxide at 400 0 C, and the water is determined gravimetrically by absorption in anhydrone. The extraction curves of hydrogen for zirconium hydride and uranium-zirconium hydride samples are shown in Figs. 2 and 3. Hydrogen in the samples is extracted quantitatively by heating at (1000 -- 1250) 0 C for (10 -- 40) min. Recoveries of hydrogen in the case of zirconium hydride were examined as follows: a weighed zirconium rod (5 phi x 6 mm, hydrogen -5 Torr. After the chamber was filled with purified hydrogen to 200 Torr, the rod was heated to 400 0 C for 15 h, and again weighed to determine the increase in weight. Hydrogen in the rod was then determined by the proposed method. The results are in excellent agreement with the increase in weight as shown in Table 1. Analytical results of hydrogen in zirconium hydride samples and an uranium-zirconium hydride sample are shown in Table 2. (auth.)

  7. COMPUTATIONAL AND EXPERIMENTAL MODELING OF SLURRY BUBBLE COLUMN REACTORS

    Energy Technology Data Exchange (ETDEWEB)

    Paul C.K. Lam; Isaac K. Gamwo; Dimitri Gidaspow

    2002-05-01

    The objective of this study was to develop a predictive experimentally verified computational fluid dynamics (CFD) model for gas-liquid-solid flow. A three dimensional transient computer code for the coupled Navier-Stokes equations for each phase was developed and is appended in this report. The principal input into the model is the viscosity of the particulate phase which was determined from a measurement of the random kinetic energy of the 800 micron glass beads and a Brookfield viscometer. The details are presented in the attached paper titled ''CFD Simulation of Flow and Turbulence in a Slurry Bubble Column''. This phase of the work is in press in a referred journal (AIChE Journal, 2002) and was presented at the Fourth International Conference on Multiphase Flow (ICMF 2001) in New Orleans, May 27-June 1, 2001 (Paper No. 909). The computed time averaged particle velocities and concentrations agree with Particle Image Velocimetry (PIV) measurements of velocities and concentrations, obtained using a combination of gamma-ray and X-ray densitometers, in a slurry bubble column, operated in the bubbly-coalesced fluidization regime with continuous flow of water. Both the experiment and the simulation show a down-flow of particles in the center of the column and up-flow near the walls and nearly uniform particle concentration. Normal and shear Reynolds stresses were constructed from the computed instantaneous particle velocities. The PIV measurement and the simulation produced instantaneous particle velocities. The PIV measurement and the simulation produced similar nearly flat horizontal profiles of turbulent kinetic energy of particles. To better understand turbulence we studied fluidization in a liquid-solid bed. This work was also presented at the Fourth International Conference on Multiphase Flow (ICMF 2001, Paper No. 910). To understand turbulence in risers, measurements were done in the IIT riser with 530 micron glass beads using a PIV

  8. Physical properties, fuel characteristics and P-fertilizer production related to animal slurry and products from separation of animal slurry

    DEFF Research Database (Denmark)

    Thygesen, Ole; Johnsen, Tina; Triolo, Jin Mi

    The purpose of this study was twofold: firstly to examine the relationship between dry matter content (DM) and specific gravity (SG) and viscosity in slurry and the liquid fraction from slurry separation, and secondly to investigate the potential of energy production from combustion of manure fibre...... from slurry separation and phosphorus (P) fertilizer production from recycling of the ash. Manure fibre has a positive calorific value and may be used as a CO2-neutral fuel for combustion. The ashes from combustion are rich in P, an essential fertilizer compound. The study is based on samples of animal...

  9. Process for production of a metal hydride

    Science.gov (United States)

    Allen, Nathan Tait; Butterick, III, Robert; Chin, Arthur Achhing; Millar, Dean Michael; Molzahn, David Craig

    2014-08-12

    A process for production of a metal hydride compound MH.sub.x, wherein x is one or two and M is an alkali metal, Be or Mg. The process comprises combining a compound of formula (R.sup.1O).sub.xM with aluminum, hydrogen and at least one metal selected from among titanium, zirconium, hafnium, niobium, vanadium, tantalum and iron to produce a compound of formula MH.sub.x. R.sup.1 is phenyl or phenyl substituted by at least one alkyl or alkoxy group. A mole ratio of aluminum to (R.sup.1O).sub.xM is from 0.1:1 to 1:1. The catalyst is present at a level of at least 200 ppm based on weight of aluminum.

  10. Boron hydride analogues of the fullerenes

    International Nuclear Information System (INIS)

    Quong, A.A.; Pederson, M.R.; Broughton, J.Q.

    1994-01-01

    The BH moiety is isoelectronic with C. We have studied the stability of the (BH) 60 analogue of the C 60 fullerene as well as the dual-structure (BH) 32 icosahedron, both of them being putative structures, by performing local-density-functional electronic calculations. To aid in our analysis, we have also studied other homologues of these systems. We find that the latter, i.e., the dual structure, is the more stable although the former is as stable as one of the latter's lower homologues. Boron hydrides, it seems, naturally form the dual structures used in algorithmic optimization of complex fullerene systems. Fully relaxed geometries are reported as well as electron affinities and effective Hubbard U parameters. These systems form very stable anions and we conclude that a search for BH analogues of the C 60 alkali-metal supeconductors might prove very fruitful

  11. Hydrogen storage properties of metallic hydrides

    International Nuclear Information System (INIS)

    Latroche, M.; Percheron-Guegan, A.

    2005-01-01

    Nowadays, energy needs are mainly covered by fossil energies leading to pollutant emissions mostly responsible for global warming. Among the different possible solutions for greenhouse effect reduction, hydrogen has been proposed for energy transportation. Indeed, H 2 can be seen as a clean and efficient energy carrier. However, beside the difficulties related to hydrogen production, efficient high capacity storage means are still to be developed. Many metals and alloys are able to store large amounts of hydrogen. This latter solution is of interest in terms of safety, global yield and long term storage. However, to be suitable for applications, such compounds must present high capacity, good reversibility, fast reactivity and sustainability. In this paper, we will review the structural and thermodynamic properties of metallic hydrides. (authors)

  12. CHEMICALS

    CERN Multimedia

    Medical Service

    2002-01-01

    It is reminded that all persons who use chemicals must inform CERN's Chemistry Service (TIS-GS-GC) and the CERN Medical Service (TIS-ME). Information concerning their toxicity or other hazards as well as the necessary individual and collective protection measures will be provided by these two services. Users must be in possession of a material safety data sheet (MSDS) for each chemical used. These can be obtained by one of several means : the manufacturer of the chemical (legally obliged to supply an MSDS for each chemical delivered) ; CERN's Chemistry Service of the General Safety Group of TIS ; for chemicals and gases available in the CERN Stores the MSDS has been made available via EDH either in pdf format or else via a link to the supplier's web site. Training courses in chemical safety are available for registration via HR-TD. CERN Medical Service : TIS-ME :73186 or service.medical@cern.ch Chemistry Service : TIS-GS-GC : 78546

  13. Hydrogen storage in sodium aluminum hydride.

    Energy Technology Data Exchange (ETDEWEB)

    Ozolins, Vidvuds; Herberg, J.L. (Lawrence Livermore National Laboratories, Livermore, CA); McCarty, Kevin F.; Maxwell, Robert S. (Lawrence Livermore National Laboratories, Livermore, CA); Stumpf, Roland Rudolph; Majzoub, Eric H.

    2005-11-01

    Sodium aluminum hydride, NaAlH{sub 4}, has been studied for use as a hydrogen storage material. The effect of Ti, as a few mol. % dopant in the system to increase kinetics of hydrogen sorption, is studied with respect to changes in lattice structure of the crystal. No Ti substitution is found in the crystal lattice. Electronic structure calculations indicate that the NaAlH{sub 4} and Na{sub 3}AlH{sub 6} structures are complex-ionic hydrides with Na{sup +} cations and AlH{sub 4}{sup -} and AlH{sub 6}{sup 3-} anions, respectively. Compound formation studies indicate the primary Ti-compound formed when doping the material at 33 at. % is TiAl{sub 3} , and likely Ti-Al compounds at lower doping rates. A general study of sorption kinetics of NaAlH{sub 4}, when doped with a variety of Ti-halide compounds, indicates a uniform response with the kinetics similar for all dopants. NMR multiple quantum studies of solution-doped samples indicate solvent interaction with the doped alanate. Raman spectroscopy was used to study the lattice dynamics of NaAlH{sub 4}, and illustrated the molecular ionic nature of the lattice as a separation of vibrational modes between the AlH{sub 4}{sup -} anion-modes and lattice-modes. In-situ Raman measurements indicate a stable AlH{sub 4}{sup -} anion that is stable at the melting temperature of NaAlH{sub 4}, indicating that Ti-dopants must affect the Al-H bond strength.

  14. Properties of sodium lignosulfonate as dispersant of coal water slurry

    International Nuclear Information System (INIS)

    Yang, Dongjie; Qiu, Xueqing; Zhou, Mingsong; Lou, Hongming

    2007-01-01

    In order to use lignosulfonates (a by-product of pulp and paper processes) as an effective dispersant of coal water slurry five purified sodium lignosulfonate (SL) samples with different molecular weights were prepared by fractionation using ultrafiltration and dialysis. The effect of SL on the apparent viscosity of coal water slurry (CWS) was investigated. The adsorption behavior of the SL on the coal water interface has much greater effect on the viscosity of coal water slurry. The higher adsorption amount and compact adsorption film of SL on the coal surface help reduce the viscosity of CWS, and the zeta potential is also an important factor, which is influenced by the sulfonic and carboxyl group contents of the lignosulfonate molecule. Furthermore, the SL with its molecular weight ranging from 10,000 to 30,000 has both a higher adsorbed amount and zeta potential on the coal surface and the best effect on reducing the viscosity of the coal water slurry

  15. Effect of flotation on preparation of coal-water slurries

    Energy Technology Data Exchange (ETDEWEB)

    Ding, K.; Laskowski, J.S. [University of British Columbia, Vancouver, BC (Canada)

    2009-07-01

    In order to study the effect of flotation reagents on the properties of coal-water slurry, a sub-bituminous coal was cleaned via either forward flotation or reverse flotation. The froth product from the forward flotation, obtained with the use of diesel oil and MIBC, and the tailings of the reverse flotation, carried out with dextrin-tannic acid depressants and dodecyltrimethylammonium chloride collector, were used in the preparation of coal-water slurries. It was shown that while it was possible to obtain the coal-water slurry with a high-solids content from the coal rendered hydrophilic (tailings from the coal reverse flotation), in the case of the hydrophobic product (froth product from the forward flotation) a dispersing agent was required to obtain the coal-water slurry of the same high-solids content.

  16. Environmental Consequences of Future Biogas Technologies based on Separated Slurry

    DEFF Research Database (Denmark)

    Hamelin, Lorie; Wesnæs, Marianne; Wenzel, Henrik

    2011-01-01

    different slurry separation technologies have been assessed and compared to a business-as-usual reference slurry management scenario. The results show that the environmental benefits of such biogas production are highly dependent upon the efficiency of the separation technology used to concentrate......This consequential life cycle assessment study highlights the key environmental aspects of producing biogas from separated pig and cow slurry, a relatively new but probable scenario for future biogas production, as it avoids the reliance on constrained carbon cosubstrates. Three scenarios involving...... the volatile solids in the solid fraction. The biogas scenario involving the most efficient separation technology resulted in a dry matter separation efficiency of 87% and allowed a net reduction of the global warming potential of 40%, compared to the reference slurry management. This figure comprises...

  17. Progress on radioactive waste slurry incineration with oxygen and steam

    International Nuclear Information System (INIS)

    Hoshino, M.; Hayashi, M.; Oda, I.; Nonaka, N.; Kuwayama, K.; Shigeta, T.

    1988-01-01

    The radioactive waste (radwaste) slurry generated from the nuclear power plant operation, such as spent ion-exchange resins (powdered, bead), fire-retardant oils including phosphate ester and concentrated laundry (by the wet method) liquid waste, has been stored in an untreated condition on the plant site. Recently, since the Condensate Filter Demineralizer (CFD) has been applied in advanced BWR plants, the discharged volume of untreated spent powered resin slurry has been increasing steadily. TEE and NCE have been developing an effective new volume reduction system to treat this radwaste slurry based on an innovative incineration concept. The new system is called the IOS process, the feature of which is incineration with oxygen and steam admixture instead of conventional air. The IOS process, which consists mainly of high heat load incineration with slurry atomization, and combustion gas cooling and condensation by the wet method, has several advantages which are summarized in this paper

  18. Novel hydrogen storage materials: A review of lightweight complex hydrides

    International Nuclear Information System (INIS)

    Jain, I.P.; Jain, Pragya; Jain, Ankur

    2010-01-01

    review article the fundamental understanding of the physical, chemical and structural properties of light weight hydride materials, e.g. Alanates, Borohydrides, Amide Borohydrides, Amide-Imide system, Amineborane and Alane for hydrogen storage has been presented. Lot of details of these materials has been incorporated such as synthesis, crystal structure, thermodynamics and kinetics of hydrogenation-dehydrogenation processes, reversibility and hydrogen storage capacity has been presented.

  19. Artificial exomuscle investigations for applications-metal hydride

    International Nuclear Information System (INIS)

    Crevier, Marie-Charlotte; Richard, Martin; Rittenhouse, D Matheson; Roy, Pierre-Olivier; Bedard, Stephane

    2007-01-01

    In pursuing the development of bionic devices, Victhom identified a need for technologies that could replace current motorized systems and be better integrated into the human body motion. The actuators used to obtain large displacements are noisy, heavy, and do not adequately reproduce human muscle behavior. Subsequently, a project at Victhom was devoted to the development of active materials to obtain an artificial exomuscle actuator. An exhaustive literature review was done at Victhom to identify promising active materials for the development of artificial muscles. According to this review, metal hydrides were identified as a promising technology for artificial muscle development. Victhom's investigations focused on determining metal hydride actuator potential in the context of bionics technology. Based on metal hydride properties and artificial muscle requirements such as force, displacement and rise time, an exomuscle was built. In addition, a finite element model, including heat and mass transfer in the metal hydride, was developed and implemented in FEMLAB software. (review article)

  20. Ductile zirconium powder by hydride-dehydride process

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, T S [BHABHA ATOMIC RESEARCH CENTRE, BOMBAY (INDIA); CHAUDHARY, S [NUCLEAR FUEL COMPLEX, HYDERABAD (INDIA)

    1976-09-01

    The preparation of ductile zirconium powder by the hydride-dehydride process has been described. In this process massive zirconium obtained from Kroll reduction of ZrCl/sub 4/ is first rendered brittle by hydrogenation and the hydride crushed and ground in a ball mill to the required particle size. Hydrogen is then hot vacuum extracted to yield the metal powder. The process has been successfully employed for the production of zirconium powders with low oxygen content and having hardness values in the range of 115-130 BHN, starting from a zirconium sponge of 100-120 BHN hardness. Influence of surface characteristics of the starting metal on its hydriding behaviour has been studied and the optimum hydriding-dehydriding conditions established.

  1. Electrochemical modeling of hydrogen storage in hydride-forming electrodes

    NARCIS (Netherlands)

    Ledovskikh, A.; Danilov, D.; Vermeulen, P.; Notten, P.H.L.

    2009-01-01

    An electrochemical kinetic model (EKM) is developed, describing the electrochemical hydrogen storage in hydride-forming materials under equilibrium conditions. This model is based on first principles of electrochemical reaction kinetics and statistical thermodynamics and describes the complex,

  2. Development of zirconium hydride highly effective moderator materials

    International Nuclear Information System (INIS)

    Yin Changgeng

    2005-10-01

    The zirconium hydride with highly content of hydrogen and low density is new efficient moderator material for space nuclear power reactor. Russia has researched it to use as new highly moderator and radiation protection materials. Japanese has located it between the top of pressure vessel and the main protection as a shelter, the work temperature is rach to 220 degree C. The zirconium hydride moderator blocks are main parts of space nuclear power reactor. Development of zirconium hydride moderator materials have strength research and apply value. Nuclear Power Research and Design Instituteoh China (NPIC) has sep up the hydrogenation device and inspect systems, and accumurate a large of experience about zirconium hydride, also set up a strict system of QA and QC. (authors)

  3. Precipitation of hydrides in high purity niobium after different treatments

    Energy Technology Data Exchange (ETDEWEB)

    Barkov, F.; Romanenko, A.; Trenikhina, Y.; Grassellino, A.

    2013-01-01

    Precipitation of lossy non-superconducting niobium hydrides represents a known problem for high purity niobium in superconducting applications. Using cryogenic optical and laser confocal scanning microscopy we have directly observed surface precipitation and evolution of niobium hydrides in samples after different treatments used for superconducting RF cavities for particle acceleration. Precipitation is shown to occur throughout the sample volume, and the growth of hydrides is well described by the fast diffusion-controlled process in which almost all hydrogen is precipitated at $T=140$~K within $\\sim30$~min. 120$^{\\circ}$C baking and mechanical deformation are found to affect hydride precipitation through their influence on the number of nucleation and trapping centers.

  4. Complex Hydride Compounds with Enhanced Hydrogen Storage Capacity

    Energy Technology Data Exchange (ETDEWEB)

    Mosher, Daniel A.; Opalka, Susanne M.; Tang, Xia; Laube, Bruce L.; Brown, Ronald J.; Vanderspurt, Thomas H.; Arsenault, Sarah; Wu, Robert; Strickler, Jamie; Anton, Donald L.; Zidan, Ragaiy; Berseth, Polly

    2008-02-18

    The United Technologies Research Center (UTRC), in collaboration with major partners Albemarle Corporation (Albemarle) and the Savannah River National Laboratory (SRNL), conducted research to discover new hydride materials for the storage of hydrogen having on-board reversibility and a target gravimetric capacity of ≥ 7.5 weight percent (wt %). When integrated into a system with a reasonable efficiency of 60% (mass of hydride / total mass), this target material would produce a system gravimetric capacity of ≥ 4.5 wt %, consistent with the DOE 2007 target. The approach established for the project combined first principles modeling (FPM - UTRC) with multiple synthesis methods: Solid State Processing (SSP - UTRC), Solution Based Processing (SBP - Albemarle) and Molten State Processing (MSP - SRNL). In the search for novel compounds, each of these methods has advantages and disadvantages; by combining them, the potential for success was increased. During the project, UTRC refined its FPM framework which includes ground state (0 Kelvin) structural determinations, elevated temperature thermodynamic predictions and thermodynamic / phase diagram calculations. This modeling was used both to precede synthesis in a virtual search for new compounds and after initial synthesis to examine reaction details and options for modifications including co-reactant additions. The SSP synthesis method involved high energy ball milling which was simple, efficient for small batches and has proven effective for other storage material compositions. The SBP method produced very homogeneous chemical reactions, some of which cannot be performed via solid state routes, and would be the preferred approach for large scale production. The MSP technique is similar to the SSP method, but involves higher temperature and hydrogen pressure conditions to achieve greater species mobility. During the initial phases of the project, the focus was on higher order alanate complexes in the phase space

  5. Various magnetic behaviors of the hydrides deriving from the tetragonal CeFeSi-type compounds

    International Nuclear Information System (INIS)

    Chevalier, B.; Tence, S.; Gaudin, E.; Matar, S.F.; Bobet, J.-L.

    2009-01-01

    The hydrides RETXH (RE = rare earth, T = transition metal and X = Si, Ge) crystallizing in the tetragonal ZrSiCuAs-type are obtained by hydrogen absorption of the intermetallics adopting the tetragonal CeFeSi-type. The H-insertion induces interesting magnetic transitions governed by two effects: the increase of the unit cell volume linked to the H-absorption and the occurrence of the RE-H chemical bonding. Some typical examples are reported in this present brief review.

  6. Some regularities of manifestation of synergistic effects of microplasticity under electrolytic iron hydridation

    Energy Technology Data Exchange (ETDEWEB)

    Skryabina, N.E.; Spivak, L.V.; Volyntsev, A.B.

    Effect of the crystalline lattice type, material chemical composition, kinds of strain and regimes of cathode polarization on the fact of appearance and magnitude of the microplastic aftereffect deformation (MAD) has been studied. Investigation of some factors determining the MAD strengthening during the electrolytic metal hydridation allows one to define the following necessary conditions for manifestation of those synergistic effects: a sufficiently high hydrogen permeability; an existence of strains gradient and hydrogen concentration across sample cross section, an existence of some specific structural state.

  7. A study on the treatment of radioactive slurry liquid waste

    International Nuclear Information System (INIS)

    Jeong, Gyeong Hwan; Chung, U. S.; Baik, S. T.; Park, S. K.; Moon, J.S.; Jung, K.J.

    1998-12-01

    The influence of anionic flocculants on the dewatering of radioactive slurries has been investigated in a laboratory-scale vacuum filtration unit. Simultaneously the influence of certain surfactants on the dewatering of radioactive slurries with anionic flocculants has also been investigated. Test results show that the flocculated filter cake generally contains higher residual water than the unflocculated cake. The non-ionic surfactant Triton X-100 was effective in reducing the moisture content of the cake

  8. A study on the treatment of radioactive slurry liquid waste

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Gyeong Hwan; Chung, U. S.; Baik, S. T.; Park, S. K.; Moon, J.S.; Jung, K.J

    1998-12-01

    The influence of anionic flocculants on the dewatering of radioactive slurries has been investigated in a laboratory-scale vacuum filtration unit. Simultaneously the influence of certain surfactants on the dewatering of radioactive slurries with anionic flocculants has also been investigated. Test results show that the flocculated filter cake generally contains higher residual water than the unflocculated cake. The non-ionic surfactant Triton X-100 was effective in reducing the moisture content of the cake.

  9. Improved system for pumping slurry of gel explosives into boreholes

    Energy Technology Data Exchange (ETDEWEB)

    Collins, T K; Clay, R B; Udy, L L

    1967-05-16

    A method is described for injecting an explosive slurry into a borehole containing water. The slurry is heavier than water and is pumped through the tubing to a depth close to the bottom of the well. Injection is continued until all water has been displaced above the lower end of the tubing. This type of immiscible displacement results in substantially no mixing between the water and the explosive. (15 claims)

  10. Comparison of catalytic ethylene polymerization in slurry and gas phase

    OpenAIRE

    Daftaribesheli, Majid

    2009-01-01

    Polyethylene (PE) with the annual consumption of 70 million tones in 2007 is mostly produced in slurry, gas-phase or combination of both processes. This work focuses on a comparison between the slurry and gas phase processes. Why does PE produced in theses two processes can show extremely different properties and extremely different reaction behaviour even if the same Ziegler-Natta (ZN) catalyst is used? Generally, it is known that the reason can be found in the differences of local condition...

  11. Reactions of zinc hydride and magnesium hydride with pyridine; synthesis and characterization of 1,4-dihydro-1-pyridylzinc and -magnesium complexes

    NARCIS (Netherlands)

    Koning, A.J. de; Boersma, J.; Kerk, G.J.M. van der

    1980-01-01

    The synthesis and characterization of 1,4-dihydro-1-pyridylzinc and -magnesium complexes are described. Zinc hydride and magnesium hydride dissolve in and react with pyridine, and the reaction has been studied in detail in the case of zinc hydride. Evaporation of the solvent after 1–2 hours at 0°C

  12. Spectroscopy of helium hydride and triatomic hydrogen molecules

    International Nuclear Information System (INIS)

    Ketterle, W.

    1986-07-01

    Helium hydride and triatomic hydrogen has been produced by charge exchange between fast mass selected beams of molecular ions and alkali vapor. Using this method, the first discrete spectra of helium hydride were obtained. Fine electronic transitions with resolved rotational structure were observed in the visible and near infrared. Four isotopic mixtures were studied. Furthermore the first lifetime measurement of triatomic hydrogen states were performed and compared to theoretical predictions. (orig.)

  13. Proton location in metal hydrides using electron spin resonance

    International Nuclear Information System (INIS)

    Venturini, E.L.

    1979-01-01

    Electron spin resonance (ESR) of dilute paramagnetic ions establishes the site symmetry of these ions. In the case of metal hydrides the site symmetry is determined by the number and location of neighboring protons. Typical ESR spectra for trivalent erbium in scandium and yttrium hydrides are presented and analyzed, and this technique is shown to be a versatile microscopic probe of the location, net charge and occupation probability of nearby protons

  14. The Production of Uranium Metal by Metal Hydrides Incorporated

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, P. P.

    1943-01-01

    Metal Hydrides Incorporated was a pioneer in the production of uranium metal on a commercial scale and supplied it to all the laboratories interested in the original research, before other methods for its production were developed. Metal Hydrides Inc. supplied the major part of the metal for the construction of the first experimental pile which, on December 2, 1942, demonstrated the feasibility of the self-sustaining chain reaction and the release of atomic energy.

  15. Determination of sulfur in coal and ash slurry by high-resolution continuum source electrothermal molecular absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Nakadi, Flávio V.; Rosa, Lilian R.; Veiga, Márcia A.M.S. da, E-mail: mamsveiga@ffclrp.usp.br

    2013-10-01

    We propose a procedure for the determination of sulfur in coal slurries by high resolution continuum source electrothermal molecular absorption spectrometry. The slurry, whose concentration is 1 mg mL{sup −1}, was prepared by mixing 50 mg of the sample with 5% v/v nitric acid and 0.04% m/v Triton X-100 and was homogenized manually. It sustained good stability. The determination was performed via CS molecular absorption at 257.592 nm, and the optimized vaporization temperature was 2500 °C. The accuracy of the method was ensured by analysis of certified reference materials SRM 1632b (trace elements in coal) and SRM 1633b (coal fly ash) from the National Institute of Standards and Technology, using external calibration with aqueous standards prepared in the same medium and used as slurry. We achieved good agreement with the certified reference materials within 95% confidence interval, LOD of 0.01% w/w, and RSD of 6%, which confirms the potential of the proposed method. - Highlights: • HR-CS ET MAS as a technique to determine sulfur in coal and ash • Utilization of (coal and coal fly ash) slurry as a sample preparation • Simple and fast method, which uses external calibration with aqueous standards without chemical modifier.

  16. Investigation of aqueous slurries as fusion reactor blankets

    International Nuclear Information System (INIS)

    Schuller, M.J.

    1985-01-01

    Numerical and experimental studies were carried out to assess the feasibility of using an aqueous slurry, with lithium in its solid component, to meet the tritium breeding, cooling, and shielding requirements of a controlled thermonuclear reactor (CTR). The numerical studies were designed to demonstrate the theoretical ability of a conceptual slurry blanket to breed adequate tritium to sustain the CTR. The experimental studies were designed to show that the tritium retention characteristics of likely solid components for the slurry were conducive to adequate tritium recovery without the need for isotopic separation. The numerical portion of this work consisted in part of using ANISN, a one-dimensional finite difference neutron transport code, to model the neutronic performance of the slurry blanket concept. The parameters governing tritium production and retention in a slurry were computed and used to modify the results of the ANISN computer runs. The numerical work demonstrated that the slurry blanket was only marginally capable of breeding sufficient tritium without the aid of a neutron multiplying region. The experimental portion of this work consisted of several neutron irradiation experiments, which were designed to determine the retention abilities of LiF particles

  17. Environmental consequences of future biogas technologies based on separated slurry.

    Science.gov (United States)

    Hamelin, Lorie; Wesnæs, Marianne; Wenzel, Henrik; Petersen, Bjørn M

    2011-07-01

    This consequential life cycle assessment study highlights the key environmental aspects of producing biogas from separated pig and cow slurry, a relatively new but probable scenario for future biogas production, as it avoids the reliance on constrained carbon cosubstrates. Three scenarios involving different slurry separation technologies have been assessed and compared to a business-as-usual reference slurry management scenario. The results show that the environmental benefits of such biogas production are highly dependent upon the efficiency of the separation technology used to concentrate the volatile solids in the solid fraction. The biogas scenario involving the most efficient separation technology resulted in a dry matter separation efficiency of 87% and allowed a net reduction of the global warming potential of 40%, compared to the reference slurry management. This figure comprises the whole slurry life cycle, including the flows bypassing the biogas plant. This study includes soil carbon balances and a method for quantifying the changes in yield resulting from increased nitrogen availability as well as for quantifying mineral fertilizers displacement. Soil carbon balances showed that between 13 and 50% less carbon ends up in the soil pool with the different biogas alternatives, as opposed to the reference slurry management.

  18. Experimental study on the rheological behaviour of coal ash slurries

    Directory of Open Access Journals (Sweden)

    Assefa K.M.

    2015-12-01

    Full Text Available Extensive experimental investigations were carried out to evaluate the rheological behaviour of fly ash (FA slurry without and with the addition of bottom ash (BA and BA slurry without and with the addition of FA. The FA slurries exhibited Bingham behaviour at solid mass concentrations ranging from 60–65% and mixing proportions from 10– 40%. A substantial reduction in yield stress was observed except for mixing proportion of 40% on which the yield stress and viscosity were increased drastically for all solid concentrations. Hence, it can be concluded that the yield stress and viscosity of FA slurry were very much influenced by adding BA up to the mixing proportion of 30%. The rheological behaviour of BA slurries with and without the addition of FA in proportions of 10–50% was investigated and exhibited Newtonian behaviours for solid mass concentrations ranging from 30–50% without and with the addition of FA. The viscosity increases with increasing the solid concentrations and proportion of FA. Based on these experimental data, a correlation was developed to predict the relative viscosity of BA slurries as a function of solid volume fraction and FA mass proportion of 0–50% and the RMSE and R2 values showed good agreement between the experimental and the predicted data.

  19. The use of metal hydrides in fuel cell applications

    Directory of Open Access Journals (Sweden)

    Mykhaylo V. Lototskyy

    2017-02-01

    Full Text Available This paper reviews state-of-the-art developments in hydrogen energy systems which integrate fuel cells with metal hydride-based hydrogen storage. The 187 reference papers included in this review provide an overview of all major publications in the field, as well as recent work by several of the authors of the review. The review contains four parts. The first part gives an overview of the existing types of fuel cells and outlines the potential of using metal hydride stores as a source of hydrogen fuel. The second part of the review considers the suitability and optimisation of different metal hydrides based on their energy efficient thermal integration with fuel cells. The performances of metal hydrides are considered from the viewpoint of the reversible heat driven interaction of the metal hydrides with gaseous H2. Efficiencies of hydrogen and heat exchange in hydrogen stores to control H2 charge/discharge flow rates are the focus of the third section of the review and are considered together with metal hydride – fuel cell system integration issues and the corresponding engineering solutions. Finally, the last section of the review describes specific hydrogen-fuelled systems presented in the available reference data.

  20. Metal hydrides based high energy density thermal battery

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Zhigang Zak, E-mail: zak.fang@utah.edu [Department of Metallurgical Engineering, The University of Utah, 135 South 1460 East, Room 412, Salt Lake City, UT 84112-0114 (United States); Zhou, Chengshang; Fan, Peng [Department of Metallurgical Engineering, The University of Utah, 135 South 1460 East, Room 412, Salt Lake City, UT 84112-0114 (United States); Udell, Kent S. [Department of Metallurgical Engineering, The University of Utah, 50 S. Central Campus Dr., Room 2110, Salt Lake City, UT 84112-0114 (United States); Bowman, Robert C. [Department of Metallurgical Engineering, The University of Utah, 135 South 1460 East, Room 412, Salt Lake City, UT 84112-0114 (United States); Vajo, John J.; Purewal, Justin J. [HRL Laboratories, LLC, 3011 Malibu Canyon Road, Malibu, CA 90265 (United States); Kekelia, Bidzina [Department of Metallurgical Engineering, The University of Utah, 50 S. Central Campus Dr., Room 2110, Salt Lake City, UT 84112-0114 (United States)

    2015-10-05

    Highlights: • The principle of the thermal battery using advanced metal hydrides was demonstrated. • The thermal battery used MgH{sub 2} and TiMnV as a working pair. • High energy density can be achieved by the use of MgH{sub 2} to store thermal energy. - Abstract: A concept of thermal battery based on advanced metal hydrides was studied for heating and cooling of cabins in electric vehicles. The system utilized a pair of thermodynamically matched metal hydrides as energy storage media. The pair of hydrides that was identified and developed was: (1) catalyzed MgH{sub 2} as the high temperature hydride material, due to its high energy density and enhanced kinetics; and (2) TiV{sub 0.62}Mn{sub 1.5} alloy as the matching low temperature hydride. Further, a proof-of-concept prototype was built and tested, demonstrating the potential of the system as HVAC for transportation vehicles.

  1. U-8 wt %Mo and 7 wt %Mo alloys powder obtained by an hydride-de hydride process

    International Nuclear Information System (INIS)

    Balart, Silvia N.; Bruzzoni, Pablo; Granovsky, Marta S.; Gribaudo, Luis M. J.; Hermida, Jorge D.; Ovejero, Jose; Rubiolo, Gerardo H.; Vicente, Eduardo E.

    2000-01-01

    Uranium-molybdenum alloys are been tested as a component in high-density LEU dispersion fuels with very good performances. These alloys need to be transformed to powder due to the manufacturing requirements of the fuels. One method to convert ductile alloys into powder is the hydride-de hydride process, which takes advantage of the ability of the U-α phase to transform to UH 3 : a brittle and relatively low-density compound. U-Mo alloys around 7 and 8 wt % Mo were melted and heat treated at different temperature ranges in order to partially convert γ -phase to α -phase. Subsequent hydriding transforms this α -phase to UH 3 . The volume change associated to the hydride formation embrittled the material which ends up in a powdered alloy. Results of the optical metallography, scanning electron microscopy, X-ray diffraction during different steps of the process are shown. (author)

  2. Raman and photoelectron spectroscopic investigation of high-purity niobium materials: Oxides, hydrides, and hydrocarbons

    Science.gov (United States)

    Singh, Nageshwar; Deo, M. N.; Nand, Mangla; Jha, S. N.; Roy, S. B.

    2016-09-01

    We present investigations of the presence of oxides, hydrides, and hydrocarbons in high-purity (residual resistivity ratio, ˜300) niobium (Nb) materials used in fabrication of superconducting radio frequency (SRF) cavities for particle accelerators. Raman spectroscopy of Nb materials (as-received from the vendor as well as after surface chemical- and thermal processing) revealed numerous peaks, which evidently show the presence of oxides (550 cm-1), hydrides (1277 and 1385 cm-1: ˜80 K temperature), and groups of hydrocarbons (1096, 2330, 2710, 2830, 2868, and 3080 cm-1). The present work provides direct spectroscopic evidence of hydrides in the electropolished Nb materials typically used in SRF cavities. Raman spectroscopy thus can provide vital information about the near-surface chemical species in niobium materials and will help in identifying the cause for the performance degradation of SRF cavities. Furthermore, photoelectron spectroscopy was performed on the Nb samples to complement the Raman spectroscopy study. This study reveals the presence of C and O in the Nb samples. Core level spectra of Nb (doublet 3d5/2 and 3d3/2) show peaks near 206.6 and 209.4 eV, which can be attributed to the Nb5+ oxidation state. The core level spectra of C 1 s of the samples are dominated by graphitic carbon (binding energy, 284.6 eV), while the spectra of O 1 s are asymmetrically peaked near binding energy of ˜529 eV, and that indicates the presence of metal-oxide Nb2O5. The valence-band spectra of the Nb samples are dominated by a broad peak similar to O 2p states, but after sputtering (for 10 min) a peak appears at ˜1 eV, which is a feature of the elemental Nb atom.

  3. Effect of electronegativity on the mechanical properties of metal hydrides with a fluorite structure

    International Nuclear Information System (INIS)

    Ito, Masato; Setoyama, Daigo; Matsunaga, Junji; Muta, Hiroaki; Kurosaki, Ken; Uno, Masayoshi; Yamanaka, Shinsuke

    2006-01-01

    Bulk titanium, yttrium, and zirconium hydrides, which have the same structure as that of fluorite-type fcc C 1, were produced and their mechanical properties were investigated. With an increase in the hydrogen content, the lattice parameters of titanium and zirconium hydrides increased, whereas those of yttrium hydride decreased. The elastic moduli of titanium and zirconium hydrides decreased by hydrogen addition, whereas those of yttrium hydride increased. There are linear relations between the electronegativities and hydrogen content dependence of the properties. Therefore, the mechanical properties of the metal hydrides are considered to be determined by a common rule based on the electronegativity

  4. Manganese Silylene Hydride Complexes: Synthesis and Reactivity with Ethylene to Afford Silene Hydride Complexes.

    Science.gov (United States)

    Price, Jeffrey S; Emslie, David J H; Britten, James F

    2017-05-22

    Reaction of the ethylene hydride complex trans-[(dmpe) 2 MnH(C 2 H 4 )] (1) with Et 2 SiH 2 at 20 °C afforded the silylene hydride [(dmpe) 2 MnH(=SiEt 2 )] (2 a) as the trans-isomer. By contrast, reaction of 1 with Ph 2 SiH 2 at 60 °C afforded [(dmpe) 2 MnH(=SiPh 2 )] (2 b) as a mixture of the cis (major) and trans (minor) isomers, featuring a Mn-H-Si interaction in the former. The reaction to form 2 b also yielded [(dmpe) 2 MnH 2 (SiHPh 2 )] (3 b); [(dmpe) 2 MnH 2 (SiHR 2 )] (R=Et (3 a) and Ph (3 b)) were accessed cleanly by reaction of 2 a and 2 b with H 2 , and the analogous reactions with D 2 afforded [(dmpe) 2 MnD 2 (SiHR 2 )] exclusively. Both 2 a and 2 b engaged in unique reactivity with ethylene, generating the silene hydride complexes cis-[(dmpe) 2 MnH(R 2 Si=CHMe)] (R=Et (4 a), Ph (4 b)). Compounds trans-2 a, cis-2 b, 3 b, and 4 b were crystallographically characterized, and bonding in 2 a, 2 b, 4 a, and 4 b was probed computationally. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. The Processing of Titanium Hydride Powders into Uniform Hollow Spheres

    National Research Council Canada - National Science Library

    Hurysz, Kevin

    1998-01-01

    .... Slurry suitability is dictated by the solids loading and degree of dispersion, the influence of polymer additives on rheology and the evaporation of acetone, and the minimization of impurities...

  6. Influence of uranium hydride oxidation on uranium metal behaviour

    International Nuclear Information System (INIS)

    Patel, N.; Hambley, D.; Clarke, S.A.; Simpson, K.

    2013-01-01

    This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)

  7. Influence of uranium hydride oxidation on uranium metal behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Patel, N.; Hambley, D. [National Nuclear Laboratory (United Kingdom); Clarke, S.A. [Sellafield Ltd (United Kingdom); Simpson, K.

    2013-07-01

    This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)

  8. Developments in delayed hydride cracking in zirconium alloys

    International Nuclear Information System (INIS)

    Puls, Manfred P.

    2008-01-01

    Delayed hydride cracking (DHC) is a process of diffusion assisted localized hydride embrittlement at flaws or regions of high stress. Models of DHC propagation and initiation have been developed that capture the essential elements of this phenomenon in terms of parameters describing processes occurring at the micro-scale. The models and their predictions of experimental results applied to Zr alloys are assessed. The propagation model allows rationalization of the effect of direction of approach to temperature and of the effect of the state and morphology of the beta phase in Zr-2.5Nb on DHC velocity. The K I dependence of the DHC velocity can only be approximately rationalized by the propagation models. This is thought to be because these models approximate the DHC velocity by a constant and shape-invariant rate of growth of the hydride at the flaw and have not incorporated a coupling between the applied stress field due to the flaw alone and the precipitated hydrides that would result in a variation of the shape and density of the hydrided region with K I . Separately, models have been developed for DHC initiation at cracks and blunt flaws. Expressions are obtained for the threshold stress intensity factor, K IH , for DHC initiation at a crack. A model for K IH has been used to rationalize the experimental result that DHC initiation is not possible above a certain temperature, even when hydrides can form at the crack tip. For blunt flaws with root radii in the μm range, and engineering process zone procedure has been derived to determine the initiation conditions requiring that both a critical stress and a critical flaw tip displacement must be achieved for hydride fracture. The engineering process zone procedure takes account of the dependence of DHC initiation on the flaw's root radius. Although all of the foregoing models are capable of describing the essential features of DHC, they are highly idealized and in need of further refinement. (author)

  9. Multidimensional simulations of hydrides during fuel rod lifecycle

    International Nuclear Information System (INIS)

    Stafford, D.S.

    2015-01-01

    In light water reactor fuel rods, waterside corrosion of zirconium-alloy cladding introduces hydrogen into the cladding, where it is slightly soluble. When the solubility limit is reached, the hydrogen precipitates into crystals of zirconium hydride which decrease the ductility of the cladding and may lead to cladding failure during dry storage or transportation events. The distribution of the hydride phase and the orientation of the crystals depend on the history of the spatial temperature and stress profiles in the cladding. In this work, we have expanded the existing hydride modeling capability in the BISON fuel performance code with the goal of predicting both global and local effects on the radial, azimuthal and axial distribution of the hydride phase. We compare results from 1D simulations to published experimental data. We demonstrate the new capability by simulating in 2D a fuel rod throughout a lifecycle that includes irradiation, short-term storage in the spent fuel pool, drying, and interim storage in a dry cask. Using the 2D simulations, we present qualitative predictions of the effects of the inter-pellet gap and the drying conditions on the growth of a hydride rim. - Highlights: • We extend BISON fuel performance code to simulate lifecycle of fuel rods. • We model hydrogen evolution in cladding from reactor through dry storage. • We validate 1D simulations of hydrogen evolution against experiments. • We show results of 2D axisymmetric simulations predicting hydride formation. • We show how our model predicts formation of a hydride rim in the cladding.

  10. Permeation rates for RTF metal hydride vessels

    International Nuclear Information System (INIS)

    Klein, J.E.

    1992-01-01

    Contamination rates have been estimated for the RTF nitrogen heating and cooling system (NH and CS) due to tritium permeation through the walls of metal hydride vessels. Tritium contamination of the NH and CS will be seen shortly after start-up of the RTF with the majority of it coming from the TCAP units. Contamination rates of the NH and CS are estimated to exceed 400 Ci/year after three years of operation and will elevate tritium concentrations in the NH and CS above 6 x 10 -3 μCi/cc. To reduce tritium activity in the NH and CS, a stripper or ''getter'' bed may need to be installed in the NH and CS. Increasing the purge rate of nitrogen from the NH and CS is shown to be an impractical method for reducing tritium activity due to the high purge rates required. Stripping of the NH and CS nitrogen in the glove box stripper system will give a temporary lowering of tritium activity in the NH and CS, but tritium activity will return to its previous level in approximately two weeks

  11. Hydriding and neutron irradiation in zircaloy-4

    International Nuclear Information System (INIS)

    Ramos, Ruben Fortunato; Martin, Juan Ezequiel; Orellano, Pablo; Dorao, Carlos; Analia Soldati; Ghilarducci, Ada Albertina; Corso, Hugo Luis; Peretti, Hernan Americo; Bolcich, Juan Carlos

    2003-01-01

    The composition of Zircaloy-4 for nuclear applications is specified by the ASTM B350 Standard, that fixes the amount of alloying elements (Sn, Fe, Cr) and impurities (Ni, Hf, O, N, C, among others) to optimize good corrosion and mechanical behavior.The recycling of zircaloy-4 scrap and chips resulting from cladding tube fabrication is an interesting issue.However, changes in the final composition of the recycled material may occur due to contamination with tool pieces, stainless steel chips, turnings, etc. while scrap is stored and handled. Since the main components of the possible contaminants are Fe, Cr and Ni, it arises the interest in studying up to what limit the Fe, Ni and Cr contents could be exceeded beyond the standard specification without affecting significantly the alloy properties.Zircaloy-4 alloys elaborated with Fe, Cr and Ni additions and others of standard composition in use in nuclear plants are studied by tensile tests, SEM observations and EDS microanalysis.Some samples are tested in the initial condition and others after hydriding treatments and neutron irradiation in the RA6

  12. Predicting wear of hydrotransport pipelines in oil sand slurries

    Energy Technology Data Exchange (ETDEWEB)

    Been, J.; Lu, B.; Wolodko, J. [Alberta Research Council, Edmonton, AB (Canada); Kiel, D. [Coanda Research and Development Corp., Burnaby, BC (Canada)

    2008-07-01

    An overview of erosion and corrosion methods and techniques was presented. Wear to pipelines is influenced by slurry flow and chemistry; solids loading; and electrochemical interactions. While several experimental techniques have been developed to rank the performance of different pipeline materials, experiments do not currently provide accurate quantitative prediction of pipeline wear in the field. Rotating cylinder electrodes (RCE) and jet impingement methods are used to study the effect of flow velocity on corrosion rate. Slurry pot erosion-corrosion testers are used to rank materials for use in more dilute, less turbulent slurries. Coriolois slurry erosion testers are used to rank the erosion resistance of different pipeline materials. A pilot-scale flow loop is now being constructed by the Alberta Research Council (ARC) in order to replicate wet erosion phenomena in oil sands applications. The flow loop will be used to simulate the field conditions of oil sands pipelines and develop predictive wear data and models. Coulombic shear stress and characteristic wall velocities have been determined using a 2-layer model designed to represent flow as 2 distinct layers. To date, the flow loop pilot study has demonstrated that wear rates in smaller diameter flow loops are not significantly different than larger diameter field installations. Preliminary calculations have demonstrated that the flow loop can be used to accurately simulate the hydrodynamics and wear typically experienced in field slurry flows. 67 refs., 2 tabs., 7 figs.

  13. Gas migration through cement slurries analysis: A comparative laboratory study

    Directory of Open Access Journals (Sweden)

    Arian Velayati

    2015-12-01

    Full Text Available Cementing is an essential part of every drilling operation. Protection of the wellbore from formation fluid invasion is one of the primary tasks of a cement job. Failure in this task results in catastrophic events, such as blow outs. Hence, in order to save the well and avoid risky and operationally difficult remedial cementing, slurry must be optimized to be resistant against gas migration phenomenon. In this paper, performances of the conventional slurries facing gas invasion were reviewed and compared with modified slurry containing special gas migration additive by using fluid migration analyzer device. The results of this study reveal the importance of proper additive utilization in slurry formulations. The rate of gas flow through the slurry in neat cement is very high; by using different types of additives, we observe obvious changes in the performance of the cement system. The rate of gas flow in neat class H cement was reported as 36000 ml/hr while the optimized cement formulation with anti-gas migration and thixotropic agents showed a gas flow rate of 13.8 ml/hr.

  14. Numerical Investigation of Ice Slurry Flow in a Horizontal Pipe

    Science.gov (United States)

    Rawat, K. S.; Pratihar, A. K.

    2018-02-01

    In the last decade, phase changing material slurry (PCMS) gained much attention as a cooling medium due to its high energy storage capacity and transportability. However the flow of PCM slurry is a complex phenomenon as it affected by various parameters, i.e. fluid properties, velocity, particle size and concentration etc.. In the present work ice is used as a PCM and numerical investigation of heterogeneous slurry flow has been carried out using Eulerian KTGF model in a horizontal pipe. Firstly the present model is validated with existing experiment results available in the literature, and then model is applied to the present problem. Results show that, flow is almost homogeneous for ethanol based ice slurry with particle diameter of 0.1 mm at the velocity of 1 m/s. It is also found that ice particle distribution is more uniform at higher velocity, concentration of ice and ethanol in slurry. Results also show that ice concentration increases on the top of the pipe, and the effect of particle wall collision is more significant at higher particle diameter.

  15. Cesium platinide hydride 4Cs{sub 2}Pt.CsH: an intermetallic double salt featuring metal anions

    Energy Technology Data Exchange (ETDEWEB)

    Smetana, Volodymyr [Ames Laboratory, US Department of Energy, and Critical Materials Institute, Ames, Iowa, 50011-3020 (United States); Mudring, Anja-Verena [Ames Laboratory, US Department of Energy, and Critical Materials Institute, Ames, Iowa, 50011-3020 (United States); Department of Materials Sciences and Engineering, Iowa State University, Ames, Iowa, 50011-3111 (United States)

    2016-11-14

    With Cs{sub 9}Pt{sub 4}H a new representative of ionic compounds featuring metal anions can be added to this rare-membered family. Cs{sub 9}Pt{sub 4}H exhibits a complex crystal structure containing Cs{sup +} cations, Pt{sup 2-} and H{sup -} anions. Being a red, transparent compound its band gap is in the visible range of the electromagnetic spectrum and the ionic type of bonding is confirmed by quantum chemical calculations. This cesium platinide hydride can formally be considered as a double salt of the ''alloy'' cesium-platinum, or better cesium platinide, Cs{sub 2}Pt, and the salt cesium hydride CsH according to Cs{sub 9}Pt{sub 4}H≡4 Cs{sub 2}Pt.CsH. (copyright 2016 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. Hydrogen storage as a hydride. Citations from the International Aerospace Abstracts data base

    Science.gov (United States)

    Zollars, G. F.

    1980-01-01

    These citations from the international literature concern the storage of hydrogen in various metal hydrides. Binary and intermetallic hydrides are considered. Specific alloys discussed are iron titanium, lanthanium nickel, magnesium copper and magnesium nickel among others.

  17. The effect of stress state on zirconium hydride reorientation

    Science.gov (United States)

    Cinbiz, Mahmut Nedim

    Prior to storage in a dry-cask facility, spent nuclear fuel must undergo a vacuum drying cycle during which the spent fuel rods are heated up to elevated temperatures of ≤ 400°C to remove moisture the canisters within the cask. As temperature increases during heating, some of the hydride particles within the cladding dissolve while the internal gas pressure in fuel rods increases generating multi-axial hoop and axial stresses in the closed-end thin-walled cladding tubes. As cool-down starts, the hydrogen in solid solution precipitates as hydride platelets, and if the multiaxial stresses are sufficiently large, the precipitating hydrides reorient from their initial circumferential orientation to radial orientation. Radial hydrides can severely embrittle the spent nuclear fuel cladding at low temperature in response to hoop stress loading. Because the cladding can experience a range of stress states during the thermo-mechanical treatment induced during vacuum drying, this study has investigated the effect of stress state on the process of hydride reorientation during controlled thermo-mechanical treatments utilizing the combination of in situ X-ray diffraction and novel mechanical testing analyzed by the combination of metallography and finite element analysis. The study used cold worked and stress relieved Zircaloy-4 sheet containing approx. 180 wt. ppm hydrogen as its material basis. The failure behavior of this material containing radial hydrides was also studied over a range of temperatures. Finally, samples from reactor-irradiated cladding tubes were examined by X-ray diffraction using synchrotron radiation. To reveal the stress state effect on hydride reorientation, the critical threshold stress to reorient hydrides was determined by designing novel mechanical test samples which produce a range of stress states from uniaxial to "near-equibiaxial" tension when a load is applied. The threshold stress was determined after thermo-mechanical treatments by

  18. Precipitation of γ-zirconium hydride in zirconium

    International Nuclear Information System (INIS)

    Carpenter, G.J.C.

    1978-01-01

    A mechanism for the precipitation of γ-zirconium hydride in zirconium is presented which does not require the diffusion of zirconium. The transformation is completed by shears caused by 1/3 (10 anti 10) Shockley partial dislocations on alternate zirconium basal planes, either by homogeneous nucleation or at lattice imperfections. Homogeneous nucleation is considered least likely in view of the large nucleation barrier involved. Hydrides may form at dislocations by the generation of partials by means of either a pole or ratchet mechanism. The former requires dislocations with a component of Burgers vector along the c-axis, but contrast experiments show that these are not normally observed in annealed zirconium. It is therefore most likely that intragranular hydrides form at the regular 1/3 (11 anti 20) dislocations, possibly by means of a ratchet mechanism. Contrast experiments in the electron microscope show that the precipitates have a shear character consistent with the mechanism suggested. The possibility that the shear dislocations associated with the hydrides are emissary dislocations is considered and a model suggested in which this function is satisfied together with the partial relief of misfit stresses. The large shear strains associated with the precipitation mechanism may play an important role in the preferential orientation of hydrides under stress

  19. Sodium-based hydrides for thermal energy applications

    Science.gov (United States)

    Sheppard, D. A.; Humphries, T. D.; Buckley, C. E.

    2016-04-01

    Concentrating solar-thermal power (CSP) with thermal energy storage (TES) represents an attractive alternative to conventional fossil fuels for base-load power generation. Sodium alanate (NaAlH4) is a well-known sodium-based complex metal hydride but, more recently, high-temperature sodium-based complex metal hydrides have been considered for TES. This review considers the current state of the art for NaH, NaMgH3- x F x , Na-based transition metal hydrides, NaBH4 and Na3AlH6 for TES and heat pumping applications. These metal hydrides have a number of advantages over other classes of heat storage materials such as high thermal energy storage capacity, low volume, relatively low cost and a wide range of operating temperatures (100 °C to more than 650 °C). Potential safety issues associated with the use of high-temperature sodium-based hydrides are also addressed.

  20. Mechanisms of hydrogen induced delayed cracking in hydride forming materials

    International Nuclear Information System (INIS)

    Dutton, R.; Nuttall, K.; Puls, M.P.; Simpson, L.A.

    1977-01-01

    Mechanisms which have been formulated to describe delayed hydrogen cracking in hydride-forming metals are reviewed and discussed. Particular emphasis is placed on the commercial alloy Zr--2.5% Nb (Cb) which is extensively used in nuclear reactor core components. A quantitative model for hydrogen cracking in this material is presented and compared with available experimental data. The kinetics of crack propagation are controlled by the growth of hydrides at the stressed crack tip by the diffusive ingress of hydrogen into this region. The driving force for the diffusion flux is provided by the local stress gradient which interacts with both hydrogen atoms in solution and hydrogen atoms being dissolved and reprecipitated at the crack tip. The model is developed using concepts of elastoplastic fracture mechanics. Stage I crack growth is controlled by hydrides growing in the elastic stress gradient, while Stage II is controlled by hydride growth in the plastic zone at the crack tip. Recent experimental observations are presented which indicate that the process occurs in an intermittent fashion; hydride clusters accumulate at the crack tip followed by unstable crack advance and subsequent crack arrest in repeated cycles

  1. Mechanisms of hydrogen induced delayed cracking in hydride forming materials

    International Nuclear Information System (INIS)

    Dutton, R.; Nuttall, K.; Puls, M.P.; Simpson, L.A.

    1977-01-01

    Mechanisms which have been formulated to describe delayed hydrogen cracking in hydride-forming metals are reviewed and discussed. Particular emphasis is placed on the commercial alloy Zr-2.5 pct Nb which is extensively used in nuclear reactor core components. A quantitative model for hydrogen cracking in this material is presented and compared with available experimental data. The kinetics of crack propagation are controlled by the growth of hydrides at the stressed crack tip by the diffusive ingress of hydrogen into this region. The driving force for the diffusion flux is provided by the local stress gradient which interacts with both hydrogen atoms in solution and hydrogen atoms being dissolved and reprecipitated at the crack tip. The model is developed using concepts of elastoplastic fracture mechanics. Stage I crack growth is controlled by hydrides growing in the elastic stress gradient, while Stage II is controlled by hydride growth in the plastic zone at the crack tip. Recent experimental observations are presented which indicate that the process occurs in an intermittent fashion; hydride clusters accumulate at the crack tip followed by unstable crack advance and subsequent crack arrest in repeated cycles. 55 refs., 6 figs

  2. Protozoan predation in soil slurries compromises determination of contaminant mineralization potential

    International Nuclear Information System (INIS)

    Badawi, Nora; Johnsen, Anders R.; Brandt, Kristian K.; Sørensen, Jan; Aamand, Jens

    2012-01-01

    Soil suspensions (slurries) are commonly used to estimate the potential of soil microbial communities to mineralize organic contaminants. The preparation of soil slurries disrupts soil structure, however, potentially affecting both the bacterial populations and their protozoan predators. We studied the importance of this “slurry effect” on mineralization of the herbicide 2-methyl-4-chlorophenoxyacetic acid (MCPA, 14 C-labelled), focussing on the effects of protozoan predation. Mineralization of MCPA was studied in “intact” soil and soil slurries differing in soil:water ratio, both in the presence and absence of the protozoan activity inhibitor cycloheximide. Protozoan predation inhibited mineralization in dense slurry of subsoil (soil:water ratio 1:3), but only in the most dilute slurry of topsoil (soil:water ratio 1:100). Our results demonstrate that protozoan predation in soil slurries may compromise quantification of contaminant mineralization potential, especially when the initial density of degrader bacteria is low and their growth is controlled by predation during the incubation period. - Highlights: ► We studied the protozoan impact on MCPA mineralization in soil slurries. ► Cycloheximide was used as protozoan inhibitor. ► Protozoa inhibited MCPA mineralization in dilute topsoil slurry and subsoil slurry. ► Mineralization potentials may be underestimated when using soil slurries. - Protozoan predation may strongly bias the quantification of mineralization potential when performed in soil slurries, especially when the initial density of degrader bacteria is low such as in subsoil or very dilute topsoil slurries.

  3. Slurry burner for mixture of carbonaceous material and water

    Science.gov (United States)

    Nodd, D.G.; Walker, R.J.

    1985-11-05

    The present invention is intended to overcome the limitations of the prior art by providing a fuel burner particularly adapted for the combustion of carbonaceous material-water slurries which includes a stationary high pressure tip-emulsion atomizer which directs a uniform fuel into a shearing air flow as the carbonaceous material-water slurry is directed into a combustion chamber, inhibits the collection of unburned fuel upon and within the atomizer, reduces the slurry to a collection of fine particles upon discharge into the combustion chamber, and regulates the operating temperature of the burner as well as primary air flow about the burner and into the combustion chamber for improved combustion efficiency, no atomizer plugging and enhanced flame stability.

  4. Gas distribution effects on waste properties: Viscosities of bubbly slurries

    International Nuclear Information System (INIS)

    Gauglitz, P.A.; Shah, R.R.; Davis, R.L.

    1994-09-01

    The retention and episodic release of flammable gases are critical safety concerns for double-shell tanks that contain waste slurries. The rheological behavior of the waste, particularly of the settled sludge, is critical to characterizing the tendency of the waste to retain gas bubbles. The presence of gas bubbles is expected to affect the rheology of the sludge, but essentially no literature data are available to assess the effect of bubbles. Accordingly, the objectives of this study are to develop models for the effect of gas bubbles on the viscosity of a particulate slurry, develop an experimental method (capillary rheometer), collect data on the viscosity of a bubbly slurry, and develop a theoretical basis for interpreting the experimental data from the capillary rheometer

  5. Radioactive waste slurry dehydrating and drum filling device

    International Nuclear Information System (INIS)

    Ichihashi, Toshio; Abe, Kazuaki; Hasegawa, Akira

    1981-01-01

    Purpose: To obtain a device for simultaneously filling and dehydrating radioactive waste in a waste can without the necessity of a special device for dehydration. Constitution: This device includes a radioactive waste storage tank, a pump for supplying the waste from the tank to a can, a drain tube having a filter at the lower end and installed displaceable in the axial direction of the can, and a drain pump. The slurry stored in the radioactive waste storage tank is supplied by the pump to the can, and the feedwater in the slurry is removed by another pump through a drain pipe having a filter which does not pass solid content from the can. Accordingly, as the slurry is filled in the can, the feedwater contained therein is removed. Consequently, it can simultaneously dehydrate and fill the dehydrated waste in the can. (Yoshihara, H.)

  6. Preconcentration and in-situ photoreduction of trace selenium using TiO2 nanoparticles, followed by its determination by slurry photochemical vapor generation atomic fluorescence spectrometry

    International Nuclear Information System (INIS)

    Yang, Wulin; Wu, Li; Zhu, Xiaofan; Gao, Ying; Hou, Xiandeng; Zheng, Chengbin

    2014-01-01

    We have developed a method for the determination of trace levels of total selenium in water samples. It integrates preconcentration, in-situ photoreduction and slurry photochemical vapor generation using TiO 2 nanoparticles, and the determination of total selenium by AFS. The Se(IV) and Se(VI) species were adsorbed on a slurry of TiO 2 nanoparticles which then were exposed to UV irradiation in the presence of formic acid to form volatile selenium species. The detection limits were improved 17-fold compared to hydride generation and 56-fold compared to photochemical vapor generation, both without any preconcentration. No significant difference was found in the limits of detection (LODs) for Se(IV) and Se(VI). The LOD is as low as 0.8 ng L −1 , the precision is better than 4.5 % (at a level of 0.1 μg L −1 of selenium). The method gave good recoveries when applied to the determination of total selenium in a certified tissue reference material (DORM-3) and in spiked drinking water and wastewater samples containing high concentrations of transition and noble metal ions. It also excels by very low LODs, a significant enhancement of sample throughput, reduced reagent consumption and sample loss, and minimal interference by transition and noble metal ions. (author)

  7. Flow injection electrochemical hydride generation inductively coupled plasma time-of-flight mass spectrometry for the simultaneous determination of hydride forming elements and its application to the analysis of fresh water samples

    International Nuclear Information System (INIS)

    Bings, Nicolas H.; Stefanka, Zsolt; Mallada, Sergio Rodriguez

    2003-01-01

    A flow injection (FI) method was developed using electrochemical hydride generation (EcHG) as a sample introduction system, coupled to an inductively coupled plasma time-of-flight mass spectrometer (ICP-TOFMS) for rapid and simultaneous determination of six elements forming hydrides (As, Bi, Ge, Hg, Sb and Se). A novel low volume electrolysis cell, especially suited for FI experiments was designed and the conditions for simultaneous electrochemical hydride generation (EcHG; electrolyte concentrations and flow rates, electrolysis voltage and current) as well as the ICP-TOFMS operational parameters (carrier gas flow rate, modulation pulse width (MPW)) for the simultaneous determination of 12 isotopes were optimized. The compromise operation parameters of the electrolysis were found to be 1.4 and 3 ml min -1 for the anolyte and catholyte flow rates, respectively, using 2 M sulphuric acid. An optimum electrolysis current of 0.7 A (16 V) and an argon carrier gas flow rate of 0.91 l min -1 were chosen. A modulation pulse width of 5 μs, which influences the sensitivity through the amount of ions being collected by the MS per single analytical cycle, provided optimum results for the detection of transient signals. The achieved detection limits were compared with those obtained by using FI in combination with conventional nebulization (FI-ICP-TOFMS); values for chemical hydride generation (FI-CHG-ICP-TOFMS) were taken from the literature. By using a 200 μl sample loop absolute detection limits (3σ) in the range of 10-160 pg for As, Bi, Ge, Hg, Sb and 1.1 ng for Se and a precision of 4-8% for seven replicate injections of 20-100 ng ml -1 multielemental sample solutions were achieved. The analysis of a standard reference material (SRM) 1643d (NIST, 'Trace Elements in Water') showed good agreement with the certified values for As and Sb. Se showed a drastic difference, which is probably due to the presence of hydride-inactive Se species in the sample. Recoveries better than

  8. Infrared diode laser spectroscopy of lithium hydride

    International Nuclear Information System (INIS)

    Yamada, C.; Hirota, E.

    1988-01-01

    The fundamental and hot bands of the vibration--rotation transitions of 6 LiH, 7 LiH, 6 LiD, and 7 LiD were observed by infrared diode laser spectroscopy at Doppler-limited resolution. Lithium hydride molecules were produced by the reaction of the Li vapor with hydrogen at elevated temperatures. Some 40 transitions were observed and, after combined with submillimeter-wave spectra reported by G. M. Plummer et al. [J. Chem. Phys. 81, 4893 (1984)], were analyzed to yield Dunham-type constants with accuracies more than an order of magnitude higher than those published in the literature. It was clearly demonstrated that the Born--Oppenheimer approximation did not hold, and some parameters representing the breakdown were evaluated. The Born--Oppenheimer internuclear distance r/sup BO//sub e/ was derived to be 1.594 914 26 (59) A, where a new value of Planck's constant recommended by CODATA was employed. The relative intensity of absorption lines was measured to determine the ratio of the permanent dipole moment to its first derivative with respect to the internuclear distance: μ/sub e/ [(partialμpartialr)/sub e/ r/sub e/ ] = 1.743(86). The pressure broadening parameter Δν/sub p/ P was determined to be 6.40 (22) MHzTorr by measuring the linewidth dependence on the pressure of hydrogen, which was about four times larger than the value for the dipole--quadrupole interaction estimated by Kiefer and Bushkovitch's theory

  9. Startup of a Joule-heated glass melter with a graphite slurry

    International Nuclear Information System (INIS)

    Allen, T.L.; Routt, K.R.; Porter, M.A.

    1983-01-01

    This paper discusses the theoretical equations and physical and electrical property data of various graphite slurries for starting up a glass melter. An application test is also included to demonstrate the graphite slurry startup technique

  10. REDUCTIVE DEHALOGENATION OF A NITROGEN HETEROCYCLIC HERBICIDE IN ANOXIC AQUIFER SLURRIES

    Science.gov (United States)

    We studied the metabolic fate of bromacil in anaerobic aquifer slurries held under denitrifying, sulfate-reducing, or methanogenic conditions. Liquid chromatograhy-mass spectrometry of the slurries confirmed that bromacil was debrominated under methanogenic conditions but was not...

  11. Method and apparatus for in-situ drying investigation and optimization of slurry drying methodology

    Science.gov (United States)

    Armstrong, Beth L.; Daniel, Claus; Howe, Jane Y.; Kiggans, Jr, James O.; Sabau, Adrian S.; Wood, III, David L.; Kalnaus, Sergiy

    2016-05-10

    A method of drying casted slurries that includes calculating drying conditions from an experimental model for a cast slurry and forming a cast film. An infrared heating probe is positioned on one side of the casted slurry and a thermal probe is positioned on an opposing side of the casted slurry. The infrared heating probe may control the temperature of the casted slurry during drying. The casted slurry may be observed with an optical microscope, while applying the drying conditions from the experimental model. Observing the casted slurry includes detecting the incidence of micro-structural changes in the casted slurry during drying to determine if the drying conditions from the experimental model are optimal.

  12. Transport of Cryptosporidium parvum oocysts in soil columns following applications of raw and separated liquid slurry

    DEFF Research Database (Denmark)

    Petersen, Heidi Huus; Enemark, Heidi L.; Olsen, Annette

    2012-01-01

    to determine the effectiveness of different slurry separation technologies to remove oocysts and other pathogens, as well as whether application of separated liquid slurry to agricultural land may represent higher risks for ground water contamination as compared to application of raw slurry.......The potential for transport of viable Cryptosporidium parvum oocysts through soil to land drains and groundwater was studied using simulated rainfall and intact soil columns which were applied raw slurry or separated liquid slurry. Following irrigation and weekly samplings over a four week period......, C. parvum oocysts were detected from all soil columns regardless of slurry type and application method although recovery rates were low (liquid slurry leached 73% and 90% more oocysts compared with columns with injected and surface applied raw slurry, respectively...

  13. A fractographic distinction between hydride cracking and stress corrosion cracking in zircaloys

    International Nuclear Information System (INIS)

    Cox, B.

    1978-06-01

    The fractographic details of SCC and delayed hydride failures are compared by scanning and replica electron microscopy. It is shown that there are distinct features ascribable to the fracture of hydride platelets which are absent from SCC fractures and which distinguish them from fractures produced by delayed hydride cracking. (author)

  14. Use of triammonium salt of aurin tricarboxylic acid as risk mitigant for aluminum hydride

    Science.gov (United States)

    Cortes-Concepcion, Jose A.; Anton, Donald L.

    2017-08-08

    A process and a resulting product by process of an aluminum hydride which is modified with by physically combining in a ball milling process an aluminum hydride with a triammonium salt of aurin tricarboxylic acid. The resulting product is an aluminum hydride which is resistant to air, ambient moisture, and liquid water while maintaining useful hydrogen storage and release kinetics.

  15. A computer model for hydride blister growth in zirconium alloys

    International Nuclear Information System (INIS)

    White, A.J.; Sawatzky, A.; Woo, C.H.

    1985-06-01

    The failure of a Zircaloy-2 pressure tube in the Pickering unit 2 reactor started at a series of zirconium hydride blisters on the outside of the pressure tube. These blisters resulted from the thermal diffusion of hydrogen to the cooler regions of the pressure tube. In this report the physics of thermal diffusion of hydrogen in zirconium is reviewed and a computer model for blister growth in two-dimensional Cartesian geometry is described. The model is used to show that the blister-growth rate in a two-phase zirconium/zirconium-hydride region does not depend on the initial hydrogen concentration nor on the hydrogen pick-up rate, and that for a fixed far-field temperature there is an optimum pressure-type/calandria-tube contact temperature for growing blisters. The model described here can also be used to study large-scale effects, such as hydrogen-depletion zones around hydride blisters

  16. Hydrides and deuterides of lithium and sodium. Pt. 1

    International Nuclear Information System (INIS)

    Haque, E.

    1990-01-01

    An interionic potential model is developed for lighter and heavier alkali hydrides and deuterides. The method uses a combination of theoretical techniques, empirical fit, and a few plausible assumptions. An assessment of the derived potentials is made by calculating the lattice statics and dynamics of the crystals and by comparing both with experiment (where available) and with other calculations. The potentials are found to describe the elastic and dielectric properties reasonably well. The phonon dispersion curves of hydride and deuteride of sodium are compared with the calculations of Dyck and Jex based on force constant model approach and the results are discussed. The need for further experiments on heavier hydrides and deuterides is stressed. (author)

  17. Research in Nickel/Metal Hydride Batteries 2017

    Directory of Open Access Journals (Sweden)

    Kwo-Hsiung Young

    2018-02-01

    Full Text Available Continuing from a special issue in Batteries in 2016, nineteen new papers focusing on recent research activities in the field of nickel/metal hydride (Ni/MH batteries have been selected for the 2017 Special Issue of Ni/MH Batteries. These papers summarize the international joint-efforts in Ni/MH battery research from BASF, Wayne State University, Michigan State University, FDK Corp. (Japan, Institute for Energy Technology (Norway, Central South University (China, University of Science and Technology Beijing (China, Zhengzhou University of Light Industry (China, Inner Mongolia University of Science and Technology (China, Shenzhen Highpower (China, and University of the Witwatersrand (South Africa from 2016–2017 through reviews of AB2 metal hydride alloys, Chinese and EU Patent Applications, as well as descriptions of research results in metal hydride alloys, nickel hydroxide, electrolyte, and new cell type, comparison work, and projections of future works.

  18. New ternary hydride formation in U-Ti-H system

    International Nuclear Information System (INIS)

    Yamamoto, Takuya; Kayano, Hideo; Yamawaki, Michio.

    1991-01-01

    Hydrogen absorption properties of two titanium-rich uranium alloys, UTi 2 and UTi 4 , were studied in order to prepare and identify the recently found ternary hydride. They slowly reacted with hydrogen of the initial pressure of 10 5 Pa at 873K to form the ternary hydride. The hydrogenated specimen mainly consisted of the pursued ternary hydride but contained also U(or UO 2 ), TiH x , and some transient phases. X-ray powder diffraction and Electron Probe Micro Analysis proved that it was the UTi 2 H x with the expected MgCu 2 structure, though all the X-ray peaks were broad probably because of inhomogeneity. This compound had extremely high resistance to powdering on its formation, which showed high potential utilities for a non-powdering tritium storage system or for other purposes. (author)

  19. Optimal operation for 3 control parameters of Texaco coal-water slurry gasifier with MO-3LM-CDE algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Cuiwen; Zhang, Yakun; Gu, Xingsheng [Ministry of Education, East China Univ. of Science and Technology, Shanghai (China). Key Lab. of Advanced Control and Optimization for Chemical Processes

    2013-07-01

    Optimizing operation parameters for Texaco coal-water slurry gasifier with the consideration of multiple objectives is a complicated nonlinear constrained problem concerning 3 BP neural networks. In this paper, multi-objective 3-layer mixed cultural differential evolution (MO-3LM-CDE) algorithms which comprise of 4 multi-objective strategies and a 3LM-CDE algorithm are firstly presented. Then they are tested in 6 benchmark functions. Finally, the MO-3LM-CDE algorithms are applied to optimize 3 control parameters of the Texaco coal-water slurry gasifier in methanol production of a real-world chemical plant. The simulation results show that multi-objective optimal results are better than the respective single-objective optimal operations.

  20. Steam Explosions in Slurry-fed Ceramic Melters

    Energy Technology Data Exchange (ETDEWEB)

    Carter, J.T.

    2001-03-28

    This report assesses the potential and consequences of a steam explosion in Slurry Feed Ceramic Melters (SFCM). The principles that determine if an interaction is realistically probable within a SFCM are established. Also considered are the mitigating effects due to dissolved, non-condensable gas(es) and suspended solids within the slurry feed, radiation, high glass viscosity, and the existence of a cold cap. The report finds that, even if any explosion were to occur, however, it would not be large enough to compromise vessel integrity.

  1. Slurry Coating System Statement of Work and Specification

    Energy Technology Data Exchange (ETDEWEB)

    Chan, S. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-02-06

    The Slurry Coating System will be used to coat crystals with a polymer to support Lawrence Livermore National Security, LLC (LLNS) research and development at Lawrence Livermore National Laboratory (LLNL). The crystals will be suspended in water in a kettle. A polymer solution is added, temperature of the kettle is raised and aggregates of the crystals and polymer form. The slurry is heated under vacuum to drive off the solvents and slowly cooled while mixing to room temperature. The resulting aggregates are then filtered and dried. The performance characteristics and fielding constraints define a unique set of requirements for a new system. This document presents the specifications and requirements for the system.

  2. A coupled transport and solid mechanics formulation with improved reaction kinetics parameters for modeling oxidation and decomposition in a uranium hydride bed.

    Energy Technology Data Exchange (ETDEWEB)

    Salloum, Maher N.; Shugard, Andrew D.; Kanouff, Michael P.; Gharagozloo, Patricia E.

    2013-03-01

    Modeling of reacting flows in porous media has become particularly important with the increased interest in hydrogen solid-storage beds. An advanced type of storage bed has been proposed that utilizes oxidation of uranium hydride to heat and decompose the hydride, releasing the hydrogen. To reduce the cost and time required to develop these systems experimentally, a valid computational model is required that simulates the reaction of uranium hydride and oxygen gas in a hydrogen storage bed using multiphysics finite element modeling. This SAND report discusses the advancements made in FY12 (since our last SAND report SAND2011-6939) to the model developed as a part of an ASC-P&EM project to address the shortcomings of the previous model. The model considers chemical reactions, heat transport, and mass transport within a hydride bed. Previously, the time-varying permeability and porosity were considered uniform. This led to discrepancies between the simulated results and experimental measurements. In this work, the effects of non-uniform changes in permeability and porosity due to phase and thermal expansion are accounted for. These expansions result in mechanical stresses that lead to bed deformation. To describe this, a simplified solid mechanics model for the local variation of permeability and porosity as a function of the local bed deformation is developed. By using this solid mechanics model, the agreement between our reacting bed model and the experimental data is improved. Additionally, more accurate uranium hydride oxidation kinetics parameters are obtained by fitting the experimental results from a pure uranium hydride oxidation measurement to the ones obtained from the coupled transport-solid mechanics model. Finally, the coupled transport-solid mechanics model governing equations and boundary conditions are summarized and recommendations are made for further development of ARIA and other Sandia codes in order for them to sufficiently implement the model.

  3. Complex Metal Hydrides for Hydrogen, Thermal and Electrochemical Energy Storage

    DEFF Research Database (Denmark)

    Moller, Kasper T.; Sheppard, Drew; Ravnsbaek, Dorthe B.

    2017-01-01

    Hydrogen has a very diverse chemistry and reacts with most other elements to form compounds, which have fascinating structures, compositions and properties. Complex metal hydrides are a rapidly expanding class of materials, approaching multi-functionality, in particular within the energy storage...... inspiration to solve the great challenge of our time: efficient conversion and large-scale storage of renewable energy....... field. This review illustrates that complex metal hydrides may store hydrogen in the solid state, act as novel battery materials, both as electrolytes and electrode materials, or store solar heat in a more efficient manner as compared to traditional heat storage materials. Furthermore, it is highlighted...

  4. Hydriding and dehydriding properties of CaSi

    International Nuclear Information System (INIS)

    Aoki, Masakazu; Ohba, Nobuko; Noritake, Tatsuo; Towata, Shin-ichi

    2005-01-01

    The hydriding and dehydriding properties of CaSi were investigated both theoretically and experimentally. First-principles calculations suggested that CaSiH n is thermodynamically stable. Experimentally, the p -c isotherms clearly demonstrated plateau pressures in a temperature range of 473-573 K and the maximum hydrogen content was 1.9 weight % (wt.%) under a hydrogen pressure of 9 MPa at 473 K. The structure of CaSiH n is different from those of ZrNi hydrides, although CaSi has the CrB-type structure as well as ZrNi

  5. Thermophysical properties of solid lithium hydride and its isotopic modifications

    International Nuclear Information System (INIS)

    Mel'nikova, T.N.

    1981-01-01

    The theory of the anharmonic lattice is used to calculate the thermophysical properties (thermal expansivity, lattice constant, compressibility, and elastic moduli) of all the isotopic modifications of solid lithium hydride sup(6,7)Li(H,D,T) at temperatures up to the melting point. A general analysis of isotopic effects is carried out; in particular the reverse isotopic effect in the lattice constant is explained and the isotopic effect in melting is discussed. The results of the calculations agree with available experimental data and can be used for those isotopic modifications of lithium hydride for which there exist no experimental results. (author)

  6. Corrosion behavior of austempered ductile iron (ADI) in iron ore slurry

    African Journals Online (AJOL)

    Corrosion behavior of austempered ductile iron (ADI) in iron ore slurry was studied as a function of the microstructure developed by austempering at 380 and 300°C for different exposure time in the slurry. The corrosion rates of the ADI balls immersed in the iron ore slurry was determined using weight loss method.

  7. Effects of acidifying pig diets on emissions of ammonia, methane and sulfur from slurry during storage

    DEFF Research Database (Denmark)

    Eriksen, Jørgen; Nørgaard, Jan Værum; Poulsen, Hanne Damgaard

    2014-01-01

    and feces were collected separately from twenty-four pigs fed one of four diets (Control, +BA, +CaCl2, +BA+CaCl2) in metabolic cages, and mixed as slurry. During 103 days of storage, all acidifying diets consistently reduced pH in the slurry by 0.4 - 0.6 units. There was a strong relationship between slurry...

  8. Effects of different treatments of cattle slurry manure on water-extractable phosphorus

    NARCIS (Netherlands)

    Chapuis-Lardy, L.; Temminghoff, E.J.M.; Goede, de R.G.M.

    2003-01-01

    Cattle slurry manure applied to land increases the risk of phosphorus (P) movement to surface waters, which may lead to eutrophication. The water-extractable fraction of P in slurry manure is correlated with P concentration in runoff from soils amended with slurry smanure, and thus is an effective

  9. Draught requirement of trailing foot and shallow injection equipment for applying slurry to grassland

    NARCIS (Netherlands)

    Huijsmans, J.F.M.; Hendriks, J.L.G.; Vermeulen, G.D.

    1998-01-01

    Surface spreading of slurry leads to the inevitable emission of ammonia into the environment. Injection of slurry on grassland reduces these emissions. However, injection of slurry by deep working injector tines with goose foot chisels (wings) requires high draught forces. This type of injection has

  10. Observations on Hydride Structures at the Tip of Arrested Cracks Grown under Conditions of Delayed Hydride Cracking

    International Nuclear Information System (INIS)

    Pettersson, Kjell; Oskarsson, Magnus; Bergqvist, Hans

    2003-04-01

    One sample of Zr2.5%Nb and one sample of cold worked and stress relieved Zircaloy-4 which have been tested for hydrogen induced crack growth have been examined in the crack tip region with the aim of determining the mechanism behind the growth of cracks. The proposed mechanisms are brittle failure of a crack tip hydride and hydrogen enhanced localized shear. The examinations were done by TEM and SEM. However attempts to produce a TEM specimen with a thinned region at the tip of the crack were unsuccessful in both samples. One feature observed in the Zr2.5%Nb material may however be an indication of intense shear deformation at the tip of the crack. On the other hand all observations on the Zircaloy-4 sample indicate precipitation of hydrides ahead of the crack tip and the presence of hydrides on the crack flanks

  11. A comparison of the smeared-dislocation and super-dislocation description of a hydrided region in the context of modelling delayed hydride cracking initiation

    International Nuclear Information System (INIS)

    Smith, E.

    1994-01-01

    In quantifying the stress distribution within a hydrided region in the context of modelling delayed hydride cracking (DHC) initiation in zirconium alloys, this paper highlights the desirability of accounting for image effects, i.e. the interaction between the hydrided region and any free surface, for example a sharp crack, blunt notch or planar surface. The super-dislocation representation of a finite thickness hydrided region is ideal for accounting for image effects. It also adequately accounts for the finite thickness, t, of a hydrided region provided, as is the case in practice, we are concerned with the stress value within the hydride at distances ≥ 0.25 t from an end of the region. (Author)

  12. [Research on optimization of mathematical model of flow injection-hydride generation-atomic fluorescence spectrometry].

    Science.gov (United States)

    Cui, Jian; Zhao, Xue-Hong; Wang, Yan; Xiao, Ya-Bing; Jiang, Xue-Hui; Dai, Li

    2014-01-01

    Flow injection-hydride generation-atomic fluorescence spectrometry was a widely used method in the industries of health, environmental, geological and metallurgical fields for the merit of high sensitivity, wide measurement range and fast analytical speed. However, optimization of this method was too difficult as there exist so many parameters affecting the sensitivity and broadening. Generally, the optimal conditions were sought through several experiments. The present paper proposed a mathematical model between the parameters and sensitivity/broadening coefficients using the law of conservation of mass according to the characteristics of hydride chemical reaction and the composition of the system, which was proved to be accurate as comparing the theoretical simulation and experimental results through the test of arsanilic acid standard solution. Finally, this paper has put a relation map between the parameters and sensitivity/broadening coefficients, and summarized that GLS volume, carrier solution flow rate and sample loop volume were the most factors affecting sensitivity and broadening coefficients. Optimizing these three factors with this relation map, the relative sensitivity was advanced by 2.9 times and relative broadening was reduced by 0.76 times. This model can provide a theoretical guidance for the optimization of the experimental conditions.

  13. Effect of an Excess of Chromium and Hydriding on Zircaloy-4

    International Nuclear Information System (INIS)

    Soldati, A.; Ghilarducci, A. A; Corso, H.L.; Peretti, H.A.; Bolcich, J.C

    2003-01-01

    Results of mechanical properties and microstructure morphologies of zircaloy-4 are presented.They were obtained in several laboratory made samples of chemical composition modified with respect to the ASTM B 350 by the addition of alloying elements as well as hydrides.This work is focused mainly on the effect of 900 ppm of additional Cr in excess as compared with the standard composition alloy and with two other laboratory alloys studied before, containing 250 ppm of Ni in excess and 1000 ppm of Fe in excess, respectively.The study is carried out by means of tensile tests at room temperature and at 240C, hardness tests, SEM observations and EDS microanalysis.The neutron irradiation was carried out at Bariloche in the RA6-CNEA reactor.The results indicate that precipitates concentrate along grain boundaries in all cases, and that for higher contents of alloying elements corresponds a higher quantity of precipitates and smaller grain sizes.Except for the hydrided sample, the fracture is ductile with cavities nucleated at precipitates

  14. Rapid hydrogen gas generation using reactive thermal decomposition of uranium hydride.

    Energy Technology Data Exchange (ETDEWEB)

    Kanouff, Michael P.; Van Blarigan, Peter; Robinson, David B.; Shugard, Andrew D.; Gharagozloo, Patricia E.; Buffleben, George M.; James, Scott Carlton; Mills, Bernice E.

    2011-09-01

    Oxygen gas injection has been studied as one method for rapidly generating hydrogen gas from a uranium hydride storage system. Small scale reactors, 2.9 g UH{sub 3}, were used to study the process experimentally. Complimentary numerical simulations were used to better characterize and understand the strongly coupled chemical and thermal transport processes controlling hydrogen gas liberation. The results indicate that UH{sub 3} and O{sub 2} are sufficiently reactive to enable a well designed system to release gram quantities of hydrogen in {approx} 2 seconds over a broad temperature range. The major system-design challenge appears to be heat management. In addition to the oxidation tests, H/D isotope exchange experiments were performed. The rate limiting step in the overall gas-to-particle exchange process was found to be hydrogen diffusion in the {approx}0.5 {mu}m hydride particles. The experiments generated a set of high quality experimental data; from which effective intra-particle diffusion coefficients can be inferred.

  15. Hydrogen bonding between hydrides of the upper-right part of the periodic table

    Science.gov (United States)

    Simončič, Matjaž; Urbic, Tomaz

    2018-05-01

    One of the most important electrostatic interactions between molecules is most definitely the hydrogen bond. Understanding the basis of this interaction may offer us the insight needed to understand its effect on the macroscopic scale. Hydrogen bonding is for example the reason for anomalous properties in compounds like water and naturally life as we know it. The strength of the bond depends on numerous factors, among them the electronegativity of participating atoms. In this work we calculated the strength of hydrogen bonds between hydrides of the upper-right part of the periodic table (C, N, O, F, P, S, Cl, As, Se, Br) using quantum-chemical methods. The aim was to determine what influences the strength of strong and weak hydrogen bonds in simple hydrides. Various relationships were checked. A relation between the strength of the bond and the electronegativity of the participating atoms was found. We also observed a correlation between the strength of hydrogen bonds and the inter-atomic distances, along with the dependence on the charge transfer on the atom of the donor. We also report characteristic geometries of different dimers.

  16. NOVEL SLURRY PHASE DIESEL CATALYSTS FOR COAL-DERIVED SYNGAS

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Dragomir B. Bukur; Dr. Ketil Hanssen; Alec Klinghoffer; Dr. Lech Nowicki; Patricia O' Dowd; Dr. Hien Pham; Jian Xu

    2001-01-07

    This report describes research conducted to support the DOE program in novel slurry phase catalysts for converting coal-derived synthesis gas to diesel fuels. The primary objective of this research program is to develop attrition resistant catalysts that exhibit high activities for conversion of coal-derived syngas.

  17. Design and construction of a deep slurry trench barrier

    International Nuclear Information System (INIS)

    Deming, P.W.

    1997-01-01

    A 24 m (80 ft) deep slurry trench surrounding a former chromium manufacturing facility on the Patapsco River in Baltimore, Maryland was constructed in 1995 to contain groundwater and site Soils, and to reduce the volume of groundwater extracted to maintain an inward gradient. In 1992, an embankment made of crushed stone was constructed in the Patapsco River to make land for barrier construction outboard of the bulkheads, and to protect the barrier. Stability of the slurry-supported trench excavation in the embankment required construction from an elevated work platform. An extended reach backhoe was used to excavate the deep slurry trench and to clean the trench bottom. Soil-Bentonite backfill was prepared at a central mixing area and transported by truck to the perimeter barrier. A synthetic membrane was inserted partially into the backfill for connection to a multimedia cap, and for redundancy and erosion control in the tidal zone. Hydraulic testing of the aquitard contained by the barrier demonstrated excellent performance of the barrier and bottom closure. Detailed definition of subsurface conditions and the closure stratum was necessary for the design and successful construction of the barrier, and is recommended for comparable slurry trench construction projects

  18. Radioactive slurry waste treatment (2) - surfactants dose effects on filtration

    International Nuclear Information System (INIS)

    Jung, K. H.; Park, S. K.; Jung, W. S.; Baek, S. T.; Jung, K. J.

    1999-01-01

    The influence of anionic flocculants on the dewatering of radioactive slurries has been investigated in a laboratory-scale vacuum filtration unit. Simultaneously the influence of certain surfactants has also been investigated. Test results show that the flocculated filter cake generally contains higher residual water than the unflocculated cake. The non-ionic surfactant was effective in reducing the moisture content of the cake

  19. Developing Archetypal Machines for a Sequence of Food- Slurry ...

    African Journals Online (AJOL)

    This current work is targeted at developing various archetypal machines for the improvement of the production of these food slurries. Three prototype machines have been developed and discussed in this paper, namely, the suction sieving machine, the vibration sieving machine and the continuous flow multi-stage milling ...

  20. Automated injection of slurry samples in flow-injection analysis

    NARCIS (Netherlands)

    Hulsman, M.H.F.M.; Hulsman, M.; Bos, M.; van der Linden, W.E.

    1996-01-01

    Two types of injectors are described for introducing solid samples as slurries in flow analysis systems. A time-based and a volume-based injector based on multitube solenoid pinch valves were built, both can be characterized as hydrodynamic injectors. Reproducibility of the injections of dispersed

  1. Rheokinetic Analysis of Hydroxy Terminated Polybutadiene Based Solid Propellant Slurry

    Directory of Open Access Journals (Sweden)

    Abhay K Mahanta

    2010-01-01

    Full Text Available The cure kinetics of propellant slurry based on hydroxy-terminated polybutadiene (HTPB and toluene diisocyanate (TDI polyurethane reaction has been studied by viscosity build up method. The viscosity (ɳ–time (t plots conform to the exponential function ɳ = aebt, where a & b are empirical constants. The rate constants (k for viscosity build up at various shear rate (rpm, evaluated from the slope of dɳ/dt versus ɳ plots at different temperatures, were found to vary from 0.0032 to 0.0052 min-1. It was observed that the increasing shear rate did not have significant effect on the reaction rate constants for viscosity build up of the propellant slurry. The activation energy (Eɳ, calculated from the Arrhenius plots, was found to be 13.17±1.78 kJ mole-1, whereas the activation enthalpy (∆Hɳ* and entropy (∆Sɳ* of the propellant slurry, calculated from Eyring relationship, were found to be 10.48±1.78 kJ mole-1 and –258.51± 5.38 J mole-1K-1, respectively. The reaction quenching temperature of the propellant slurry was found to be -9 ° C, based upon the experimental data. This opens up an avenue for a “freeze-and-store”, then “warm-up and cast”, mode of manufacturing of very large solid rocket propellant grains.

  2. The effect of slurry rheology on cold cap formation

    International Nuclear Information System (INIS)

    Yasuda, D.D.; Hrma, P.

    1991-01-01

    Yield stress, viscosity, and flow distance were measured on three simulated nuclear waste feeds at different temperatures and oxide loadings. Hydroxide, formate, and frit feeds, to produce glass of identical composition, were tested. Application of the results to a slurry fed waste glass melter is discussed

  3. A layered model for inclined pipe flow of settling slurry

    Czech Academy of Sciences Publication Activity Database

    Matoušek, Václav; Krupička, Jan; Kesely, Mikoláš

    2018-01-01

    Roč. 333, June (2018), s. 317-326 ISSN 0032-5910 R&D Projects: GA ČR GA17-14271S Institutional support: RVO:67985874 Keywords : inclined pipe * settling slurry * pressure drop * flow stratification * laboratory loop Impact factor: 2.942, year: 2016

  4. Debris flow rheology: Experimental analysis of fine-grained slurries

    Science.gov (United States)

    Major, Jon J.; Pierson, Thomas C.

    1992-01-01

    The rheology of slurries consisting of ≤2-mm sediment from a natural debris flow deposit was measured using a wide-gap concentric-cylinder viscometer. The influence of sediment concentration and size and distribution of grains on the bulk rheological behavior of the slurries was evaluated at concentrations ranging from 0.44 to 0.66. The slurries exhibit diverse rheological behavior. At shear rates above 5 s−1 the behavior approaches that of a Bingham material; below 5 s−1, sand exerts more influence and slurry behavior deviates from the Bingham idealization. Sand grain interactions dominate the mechanical behavior when sand concentration exceeds 0.2; transient fluctuations in measured torque, time-dependent decay of torque, and hysteresis effects are observed. Grain rubbing, interlocking, and collision cause changes in packing density, particle distribution, grain orientation, and formation and destruction of grain clusters, which may explain the observed behavior. Yield strength and plastic viscosity exhibit order-of-magnitude variation when sediment concentration changes as little as 2–4%. Owing to these complexities, it is unlikely that debris flows can be characterized by a single rheological model.

  5. Life cycle assessment of biogas from separated slurry

    Energy Technology Data Exchange (ETDEWEB)

    Hamelin, L.; Wesnaes, M.; Wenzel, H. (Univ. of Southern Denmark, Odense (Denmark)); Molt Petersen, B. (Aarhus Univ.. Faculty of Agricultural Sciences, Aarhus (Denmark))

    2010-07-01

    The environmental aspects of biogas production based on pre-treated slurry from fattening pigs and dairy cows have been investigated in a life cycle perspective. The pre-treatment consists of concentrating the slurry using a separation technology. Significant environmental benefits, compared to the status quo slurry management, can be obtained for both pig and cow slurry, especially regarding reductions of the contributions to global warming, but the results depend to a large extent on the efficiency of the separation technology. Adding separation after the biogas plant can contribute to a more efficient management of the phosphorus, and this has also been investigated. Based on the results of the study it can be concluded that: 1) The environmental benefits of biogas from separated slurry are very dependent upon the separation efficiency (for carbon, nitrogen and phosphorous). This particularly applies for carbon, as the separation efficiency defines the extent to which the degradable carbon contained in the slurry is transferred to the biogas plant. Efficient separation can be obtained by using polymer, but also by using a suitable separation technology. It could be mentioned that the decanter centrifuge used has a rather high efficiency of transferring volatile solids (VS) to the fibre fraction also without the use of polymer. 2) Biogas production from separated slurry can lead to significant reductions in the contributions to global warming, provided that the 'best available technologies' described in the report are used. That includes, among others: - a covered and short time storage of the fibre fraction before entering the biogas plant, - a 2-step biogas production where the post-digestion tank is covered with air-tight cover, - a covered storage of the degassed fibre fraction The benefits are also highly dependent upon the source of energy substituted by the biogas. 3) Based on evidences from reviewed studies, the cationic polyacrylamide polymer

  6. Odor from anaerobic digestion of swine slurry: influence of pH, temperature and organic loading

    Directory of Open Access Journals (Sweden)

    Gerardo Ortiz

    2014-12-01

    Full Text Available Farm slurry management from storage and/or treatment is the main source of odors from swine production, which are determined by factors such as operational variations (organic loading, cleaning of facilities and animal diet (pH or environmental conditions (temperature. The aim of this study was to evaluate the influence of pH, temperature and organic loading on odor generation during anaerobic digestion of swine slurry. The methodology employed batch experimental units under controlled pH (6.0, 6.5, 7.0 and 8.0 and temperature (20, 35 and 55 °C conditions. Additionally, an Upflow Anaerobic Sludge Blanket (UASB system was operated under two Organic Loading Rate (OLR conditions as Chemical Oxygen Demand (COD (Phase I: 0.4 g L-1 d-1 of COD, Phase II: 1.1 g L-1 d-1 of COD. Odor (batch and UASB reactor was evaluated by detection and recognition threshold as Dilution Threshold (D-T. Acidic conditions (pH 6.0 and thermophilic temperatures (55 °C increased odors (1,358 D-T and acidified the system (Intermediate/Total Alkalinity ratio (IT/TA: 0.85 in batch experiments. Increasing OLR on UASB reactor reduced odors from 6.3 to 9.6 D-T d-1 due to an increase in the production of biogas (0.4 to 0.6 g g-1 COD removed of biogas.

  7. Hybrid micro-particles as a magnetically-guidable decontaminant for cesium-eluted ash slurry

    Science.gov (United States)

    Namiki, Yoshihisa; Ueyama, Toshihiko; Yoshida, Takayuki; Watanabe, Ryoei; Koido, Shigeo; Namiki, Tamami

    2014-09-01

    Decontamination of the radioactive cesium that is widely dispersed owing to a nuclear power station accident and concentrated in fly ash requires an effective elimination system. Radioactive fly ash contains large amounts of water-soluble cesium that can cause severe secondary contamination and represents a serious health risk, yet its complete removal is complicated and difficult. Here it is shown that a new fine-powder formulation can be magnetically guided to eliminate cesium after being mixed with the ash slurry. This formulation, termed MagCE, consists of a ferromagnetic porous structure and alkaline- and salt-resistant nickel ferrocyanide. It has potent cesium-adsorption- and magnetic-separation-properties. Because of its resistance against physical and chemical attack such as with ash particles, as well as with the high pH and salt concentration of the ash slurry, MagCE simplifies the decontamination process without the need of the continued presence of the hazardous water-soluble cesium in the treated ash.

  8. Enhanced treatment of refinery soils with open-system slurry reactors

    International Nuclear Information System (INIS)

    Blackburn, J.W.; Lee, M.K.; Horn, W.C.

    1995-01-01

    Refinery site cleanups of residual hydrocarbons arising from long-term operations have become a concern. Because contaminated soil has been generated over many years from spills of many types of materials, it is often difficult to identify the actual spilled material. Because many of these materials are weathered, the less degradable fractions can predominate, creating a challenge for bioremedial process solutions. Open-system slurry reactors were run with an aged refinery soil after a 6-month period of field bioremediation in which 23% TPH removal resulted. The open system (a system where the liquid medium was replaced daily and the solids were retained in the reactor for 2 weeks) achieved 60 to 80% total petroleum hydrocarbon (TPH) removal based on the initial, prefield bioremediation soil concentration. A process concept twice as effective as other bioremediation schemes has been devised that takes advantage of the formation and removal of small black particulate solids in an open or continuous slurry reactor configuration. These small black particles are chemically or biologically produced in the open system and with their small size and low density are easily elutriated from the bioreactor as the liquid medium is changed. A statistically designed experiment has determined optimal values of nutrients, temperature, and mixing

  9. Nutrient Losses during Winter and Summer Storage of Separated and Unseparated Digested Cattle Slurry.

    Science.gov (United States)

    Perazzolo, Francesca; Mattachini, Gabriele; Riva, Elisabetta; Provolo, Giorgio

    2017-07-01

    Management factors affect nutrient loss during animal manure slurry storage in different ways. We conducted a pilot-scale study to evaluate carbon (C) and nitrogen (N) losses from unseparated and digested dairy slurry during winter and summer storage. In addition to season, treatments included mechanical separation of digestate into liquid and solid fractions and bimonthly mixing. Chemical analyses were performed every 2 wk for the mixed materials and at the start and end of storage for unmixed materials. The parameters examined allowed us to estimate C and N losses and examine the factors that determine these losses as well as emission patterns. Gas measurements were done every 2 wk to determine the main forms in which gaseous losses occurred. To evaluate the effect of separation, measured losses and emissions of separated liquid and solid fractions were mathematically combined using the mass separation efficiency of the mechanical separator. Nutrient losses were mainly affected by climatic conditions. Losses of C (up to 23%) from unseparated, unmixed digestate and of N (38% from combined separated fractions and from unseparated digestate) were much greater in summer than in winter, when C and N losses were losses ( losses (up to 64 and 90% of total losses, respectively) in summer. Moreover, management practices should limit NH, the main form of N losses (up to 99.5%). Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  10. ADVANCED DIAGNOSTIC TECHNIQUES FOR THREE-PHASE SLURRY BUBBLE COLUMN REACTORS (SBCR)

    Energy Technology Data Exchange (ETDEWEB)

    M.H. Al-Dahhan; M.P. Dudukovic; L.S. Fan

    2001-07-25

    This report summarizes the accomplishment made during the second year of this cooperative research effort between Washington University, Ohio State University and Air Products and Chemicals. The technical difficulties that were encountered in implementing Computer Automated Radioactive Particle Tracking (CARPT) in high pressure SBCR have been successfully resolved. New strategies for data acquisition and calibration procedure have been implemented. These have been performed as a part of other projects supported by Industrial Consortium and DOE via contract DE-2295PC95051 which are executed in parallel with this grant. CARPT and Computed Tomography (CT) experiments have been performed using air-water-glass beads in 6 inch high pressure stainless steel slurry bubble column reactor at selected conditions. Data processing of this work is in progress. The overall gas holdup and the hydrodynamic parameters are measured by Laser Doppler Anemometry (LDA) in 2 inch slurry bubble column using Norpar 15 that mimic at room temperature the Fischer Tropsch wax at FT reaction conditions of high pressure and temperature. To improve the design and scale-up of bubble column, new correlations have been developed to predict the radial gas holdup and the time averaged axial liquid recirculation velocity profiles in bubble columns.

  11. Characteristics of hydride precipitation and reorientation in spent-fuel cladding

    International Nuclear Information System (INIS)

    Chung, H.M.; Daum, R.S.; Hiller, J.M.; Billone, M.C.

    2002-01-01

    Transmission electron microscopy (TEM) was used to examine Zircaloy fuel cladding, either discharged from several PWRs and a BWR after irradiation to fluence levels of 3.3 to 8.6 X 10 21 n cm -2 (E > 1 MeV) or hydrogen-charged and heat-treated under stress to produce radial hydrides; the goal was to determine the microstructural and crystallographic characteristics of hydride precipitation. Morphologies, distributions, and habit planes of various types of hydrides were determined by stereo-TEM. In addition to the normal macroscopic hydrides commonly observed by optical microscopy, small 'microscopic' hydrides are present in spent-fuel cladding in number densities at least a few orders of magnitude greater than that of macroscopic hydrides. The microscopic hydrides, observed to be stable at least up to 333 deg C, precipitate in association with -type dislocations. While the habit plane of macroscopic tangential hydrides in the spent-fuel cladding is essentially the same as that of unirradiated unstressed Zircaloys, i.e., the [107] Zr plane, the habit plane of tangential hydrides that precipitate under high tangential stress is the [104] Zr plane. The habit plane of radial hydrides that precipitate under tangential stress is the [011] Zr pyramidal plane, a naturally preferred plane for a cladding that has 30 basal-pole texture. Effects of texture on the habit plane and the threshold stress for hydride reorientation are also discussed. (authors)

  12. In situ synchrotron X-ray diffraction study of hydrides in Zircaloy-4 during thermomechanical cycling

    Energy Technology Data Exchange (ETDEWEB)

    Cinbiz, Mahmut N., E-mail: cinbizmn@ornl.gov [Department of Mechanical and Nuclear Engineering, Pennsylvania State University, University Park, PA, 16802 (United States); Koss, Donald A., E-mail: koss@ems.psu.edu [Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA, 16802 (United States); Motta, Arthur T., E-mail: atm2@psu.edu [Department of Mechanical and Nuclear Engineering, Pennsylvania State University, University Park, PA, 16802 (United States); Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA, 16802 (United States); Park, Jun-Sang, E-mail: parkjs@aps.anl.gov [Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439 (United States); Almer, Jonathan D., E-mail: almer@aps.anl.gov [Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439 (United States)

    2017-04-15

    The d-spacing evolution of both in-plane and out-of-plane hydrides has been studied using in situ synchrotron radiation X-ray diffraction during thermo-mechanical cycling of cold-worked stress-relieved Zircaloy-4. The structure of the hydride precipitates is such that the δ{111} d-spacing of the planes aligned with the hydride platelet face is greater than the d-spacing of the 111 planes aligned with the platelet edges. Upon heating from room temperature, the δ{111} planes aligned with hydride plate edges exhibit bi-linear thermally-induced expansion. In contrast, the d-spacing of the (111) plane aligned with the hydride plate face initially contracts upon heating. These experimental results can be understood in terms of a reversal of stress state associated with precipitating or dissolving hydride platelets within the α-zirconium matrix. - Highlights: •The δ{111} d-spacings aligned with the hydride plate edges exhibit a bi-linear thermal expansion. •Stress state reversal is predicted with the onset of hydride dissolution. •During dissolution, the δ{111} planes oriented parallel to the hydride plate face initially contract upon heating. •Hydride d-spacings indicate that both in-plane (circumferential) and out-of-plane (radial) hydrides are in the same strain-state and likely in the same stress state as well.

  13. Quantifying the stress fields due to a delta-hydride precipitate in alpha-Zr matrix

    Energy Technology Data Exchange (ETDEWEB)

    Tummala, Hareesh [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Capolungo, Laurent [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tome, Carlos N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-10-19

    This report is a preliminary study on δ-hydride precipitate in zirconium alloy performed using 3D discrete dislocation dynamics simulations. The ability of dislocations in modifying the largely anisotropic stress fields developed by the hydride particle in a matrix phase is addressed for a specific dimension of the hydride. The influential role of probable dislocation nucleation at the hydride-matrix interface is reported. Dislocation nucleation around a hydride was found to decrease the shear stress (S13) and also increase the normal stresses inside the hydride. We derive conclusions on the formation of stacks of hydrides in zirconium alloys. The contribution of mechanical fields due to dislocations was found to have a non-negligible effect on such process.

  14. The influence of hydride on fracture toughness of recrystallized Zircaloy-4 cladding

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Hsiao-Hung, E-mail: 175877@mail.csc.com.tw [Institute of Nuclear Energy Research (INER), Lungtan Township, Taoyuan County 32546, Taiwan, ROC (China); China Steel Corporation, Hsiao Kang District, Kaohsiung 81233, Taiwan, ROC (China); Chiang, Ming-Feng [China Steel Corporation, Hsiao Kang District, Kaohsiung 81233, Taiwan, ROC (China); Chen, Yen-Chen [Institute of Nuclear Energy Research (INER), Lungtan Township, Taoyuan County 32546, Taiwan, ROC (China)

    2014-04-01

    In this work, RXA cladding tubes were hydrogen-charged to target hydrogen content levels between 150 and 800 wppm (part per million by weight). The strings of zirconium hydrides observed in the cross sections are mostly oriented in the circumferential direction. The fracture toughness of hydrided RXA Zircaloy-4 cladding was measured to evaluate its hydride embrittlement susceptibility. With increasing hydrogen content, the fracture toughness of hydrided RXA cladding decreases at both 25 °C and 300 °C. Moreover, highly localized hydrides (forming a hydride rim) aggravate the degradation of the fracture properties of RXA Zircaloy-4 cladding at both 25 °C and 300 °C. Brittle features in the form of quasi-cleavages and secondary cracks were observed on the fracture surface of the hydride rim, even for RXA cladding tested at 300 °C.

  15. Internal friction study of hydrides in zirconium at low hydrogen contents

    International Nuclear Information System (INIS)

    Peretti, H.A.; Corso, H.L.; Gonzalez, O.A.; Fernandez, L.; Ghilarducci, A.A.; Salva, H.R.

    1999-01-01

    Full text: Internal friction and shear modulus measurements were carried out on crystal bar zirconium in the as received and hydride conditions using an inverted forced pendulum. Hydriding was achieved in two ways: inside and out of the pendulum. The final hydrogen content determined by fusion analysis in the 'in situ' hydride sample was of 36 ppm. Another sample was hydride by the cathodic charge method with 25 ppm. The thermal solid solubility (TSS) phase boundary presents hysteresis between the precipitation (TSSP) and the dissolution (TSSD) temperatures for the zirconium hydrides. During the first thermal cycling the anelastic effects could be attributed to the δ, ε and metastable γ zirconium hydrides. After 'in situ' annealing at 490 K, these peaks completely disappear in the electrolytically charged sample, while in the 'in situ' hydride, the peaks remain with decreasing intensity. This effect can be understood in terms of the different surface conditions of the samples. (author)

  16. Slurry erosion induced surface nanocrystallization of bulk metallic glass

    Science.gov (United States)

    Ji, Xiulin; Wu, Jili; Pi, Jinghong; Cheng, Jiangbo; Shan, Yiping; Zhang, Yingtao

    2018-05-01

    Microstructure evolution and phase transformation of metallic glasses (MGs) could occur under heating condition or mechanical deformation. The cross-section of as-cast Zr55Cu30Ni5Al10 MG rod was impacted by the solid particles when subjected to erosion in slurry flow. The surface microstructure was observed by XRD before and after slurry erosion. And the stress-driven de-vitrification increases with the increase of erosion time. A microstructure evolution layer with 1-2 μm thickness was formed on the topmost eroded surface. And a short range atomic ordering prevails in the microstructure evolution layer with crystalline size around 2-3 nm embedded in the amorphous matrix. The XPS analysis reveals that most of the metal elements in the MG surface, except for Cu, were oxidized. And a composite layer with ZrO2 and Al2O3 phases were formed in the topmost surface after slurry erosion. The cooling rate during solidification of MG has a strong influence on the slurry erosion induced nanocrystallization. And a lower cooling rate favors the surface nanocrystallization because of lower activation energy and thermo-stability. Finally, the slurry erosion induced surface nanocrystallization and microstructure evolution result in surface hardening and strengthening. Moreover, the microstructure evolution mechanisms were discussed and it is related to the cooling rate of solidification and the impact-induced temperature rise, as well as the combined effects of the impact-induced plastic flow, inter-diffusion and oxidation of the metal elements.

  17. Aerosols generated by spills of viscous solutions and slurries

    International Nuclear Information System (INIS)

    Ballinger, M.Y.; Hodgson, W.H.

    1986-12-01

    Safety assessments and environmental impact statements for nuclear fuel cycle facilities require an estimate of potential airborne releases caused by accidents. Aerosols generated by accidents are being investigated by Pacific Northwest Laboratory to develop methods for estimating source terms from these accidents. Experiments were run by spilling viscous solutions and slurries to determine the mass and particle-size distribution of the material made airborne. In all cases, 1 L of solution was spilled from a height of 3 m. Aqueous solutions of sucrose (0 to 56%) gave a range of viscosities from 1.3 to 46 cp. The percent of spill mass made airborne from the spills of these solutions ranged from 0.001 to 0.0001. The mass of particles made airborne decreased as solution viscosity increased. Slurry loading ranged from 25 to 51% total solids. The maximum source airborne (0.0046 wt %) occurred with the slurry that had the lightest loading of soluble solids. The viscosity of the carrying solution also had an impact on the source term from spilling slurries. The effect of surface tension on the source term was examined in two experiments. Surface tension was halved in these spills by adding a surfactant. The maximum weight percent airborne from these spills was 0.0045, compared to 0.003 for spills with twice the surface tension. The aerodynamic mass medium diameters for the aerosols produced by spills of the viscous solutions, slurries, and low surface tension liquids ranged from 0.6 to 8.4 μm, and the geometric standard deviation ranged from 3.8 to 28.0

  18. Indian Creek-AML: Coal slurry reclamation (Kansas case history)

    International Nuclear Information System (INIS)

    Witthar, S.R.

    1998-01-01

    Black and Veatch, assisted by Jack Nawrot, developed conceptual and final designs and provided construction assistance to create grasslands and wetlands in order to reclaim an abandoned coal mine for the state of Kansas. The mine included spoils, a coal refuse dump, and slurry pond in the Indian Creek drainage basin in east central Kansas. The Indian Creek flowed from an off-site abandoned mine and through the coal slurry pond where its waters became more polluted. The intent of the reclamation project was to improve water quality and create a wildlife refuge. The coal refuse was covered and seeded with a diversity of vegetation including several grasses and legume. The slurry pond was developed into a series of large wetland cells to improve water quality. Prior to reclamation, the water leaving the site had a typical pH of 3.3, ranging from 2.4 to 5.6, an iron content which typically over 22 mg/L and ranging over 100 mg/L, and contained large amounts of coal slurry. The acid sediment in the slurry killed fish and caused visible damage to a new large concrete box culvert several miles downstream of the site. Post-reclamation water quality leaving the Indian Creek site showed immediate improvement even before vegetation was reestablished. The existing wetland treatment systems have been successfully treating water for over seven years with the pH of the water leaving the wetlands above 7 and soluble iron content less than 1 mg/L. Fish in the constructed wetlands support waterfowl which now nest onsite

  19. Dislocation/hydrogen interaction mechanisms in hydrided nanocrystalline palladium films

    International Nuclear Information System (INIS)

    Amin-Ahmadi, Behnam; Connétable, Damien; Fivel, Marc; Tanguy, Döme; Delmelle, Renaud; Turner, Stuart; Malet, Loic; Godet, Stephane; Pardoen, Thomas; Proost, Joris; Schryvers, Dominique

    2016-01-01

    The nanoscale plasticity mechanisms activated during hydriding cycles in sputtered nanocrystalline Pd films have been investigated ex-situ using advanced transmission electron microscopy techniques. The internal stress developing within the films during hydriding has been monitored in-situ. Results showed that in Pd films hydrided to β-phase, local plasticity was mainly controlled by dislocation activity in spite of the small grain size. Changes of the grain size distribution and the crystallographic texture have not been observed. In contrast, significant microstructural changes were not observed in Pd films hydrided to α-phase. Moreover, the effect of hydrogen loading on the nature and density of dislocations has been investigated using aberration-corrected TEM. Surprisingly, a high density of shear type stacking faults has been observed after dehydriding, indicating a significant effect of hydrogen on the nucleation energy barriers of Shockley partial dislocations. Ab-initio calculations of the effect of hydrogen on the intrinsic stable and unstable stacking fault energies of palladium confirm the experimental observations.

  20. A system of hydrogen powered vehicles with liquid organic hydrides

    International Nuclear Information System (INIS)

    Taube, M.

    1981-07-01

    A motor car system based on the hydrogen produced by nuclear power stations during the night in the summer, and coupled with organic liquid hydride seems to be a feasible system in the near future. Such a system is discussed and the cost is compared with gasoline. (Auth.)

  1. Process of forming a sol-gel/metal hydride composite

    Science.gov (United States)

    Congdon, James W [Aiken, SC

    2009-03-17

    An external gelation process is described which produces granules of metal hydride particles contained within a sol-gel matrix. The resulting granules are dimensionally stable and are useful for applications such as hydrogen separation and hydrogen purification. An additional coating technique for strengthening the granules is also provided.

  2. Hydrogen storage alloys for nickel/metal hydride battery

    Energy Technology Data Exchange (ETDEWEB)

    Kuriyama, Nobuhiro; Sakai, Tetsuo; Myamura, Hiroshi; Tanaka, Hideaki; Ishikawa, Hiroshi; Uehara, Itsuki [Osaka National Research Inst. (Japan)

    1996-06-01

    Efforts to improve performance of metal hydride electrodes such as substitution of alloy components, heat treatment, and surface treatment intended to change surface and bulk structure of hydrogen storage alloys, mainly LaNi{sub 5} based alloys, are reviewed. The importance of control of morphology is emphasized. (author)

  3. Cascades for hydrogen isotope separation using metal hydrides

    International Nuclear Information System (INIS)

    Hill, F.B.; Grzetic, V.

    1982-01-01

    Designs are presented for continuous countercurrent hydrogen isotope separation cascades based on the use of metal hydrides. The cascades are made up of pressure swing adsorption (PSA) or temperature swing adsorption (TSA) stages. The designs were evolved from consideration of previously conducted studies of the separation performance of four types of PSA and TSA processes

  4. Deiodination reactions using tributyltin hydride for potential labelling experiments

    International Nuclear Information System (INIS)

    Zippi, E.M.; Plourde, G.W. II; Satyamurthy, N.

    1995-01-01

    2,6-Dinitro-1-iodobenzene and 2,4-dinitro-1-iodobenzene were deiodinated with tributylin hydride at different temperatures using various addition modes. The product ratios of 1,3-dinitrobenzene and the corresponding tributylstannyldinitrobenzene compounds were determined by NMR in order to evaluate the optimum conditions for impending tritiation experiments. (Author)

  5. Modeling of electrochemical hydrogen storage in metal hydride electrodes

    NARCIS (Netherlands)

    Ledovskikh, A.; Danilov, D.; Vermeulen, P.; Notten, P.H.L.

    2010-01-01

    The recently presented Electrochemical Kinetic Model (EKM), describing the electrochemical hydrogen storage in hydride-forming materials, has been extended by the description of the solid/electrolyte interface, i.e. the charge transfer kinetics and electrical double layer charging. A complete set of

  6. Modeling of electrochemical hydrogen storage in metal hydride electrodes

    NARCIS (Netherlands)

    Ledovskikh, A.; Danilov, D.; Vermeulen, P.; Notten, P.H.L.

    2010-01-01

    The recently presented electrochemical kinetic model, describing the electrochemical hydrogen storage in hydride-forming materials, was extended by the description of the solid/electrolyte interface, i.e., the charge-transfer kinetics and electrical double-layer charging. A complete set of equations

  7. Metal Hydride assited contamination on Ru/Si surfaces

    NARCIS (Netherlands)

    Pachecka, Malgorzata; Lee, Christopher James; Sturm, Jacobus Marinus; Bijkerk, Frederik

    2013-01-01

    In extreme ultraviolet lithography (EUVL) residual tin, in the form of particles, ions, and atoms, can be deposited on nearby EUV optics. During the EUV pulse, a reactive hydrogen plasma is formed, which may be able to react with metal contaminants, creating volatile and unstable metal hydrides that

  8. Design and integration of a hydrogen storage on metallic hydrides

    International Nuclear Information System (INIS)

    Botzung, M.

    2008-01-01

    This work presents a hydrogen storage system using metal hydrides for a Combined Heat and Power (CHP) system. Hydride storage technology has been chosen due to project specifications: high volumetric capacity, low pressures (≤ 3.5 bar) and low temperatures (≤ 75 C: fuel cell temperature). During absorption, heat from hydride generation is dissipated by fluid circulation. An integrated plate-fin type heat exchanger has been designed to obtain good compactness and to reach high absorption/desorption rates. At first, the storage system has been tested in accordance with project specifications (absorption 3.5 bar, desorption 1.5 bar). Then, the hydrogen charge/discharge times have been decreased to reach system limits. System design has been used to simulate thermal and mass comportment of the storage tank. The model is based on the software Fluent. We take in consideration heat and mass transfers in the porous media during absorption/desorption. The hydride thermal and mass behaviour has been integrated in the software. The heat and mass transfers experimentally obtained have been compared to results calculated by the model. The influence of experimental and numerical parameters on the model behaviour has also been explored. (author) [fr

  9. Diastereoselectivity in the reduction of bicyclic enones with hindered hydrides

    OpenAIRE

    Camozzato, Andreza C.; Tenius, Beatriz S. M.; Oliveira, Eduardo R. de; Viegas Jr., Cláudio; Victor, Maurício M.; Silveira, Leandro G. da

    2008-01-01

    Reduction of five substituted octalones employing lithium tri-sec-butylborohydride (L-selectride®) in THF and ethyl ether led to allylic alcohols with moderate diastereoselectivity. The stereoselectivity of addition of bulky hydrides showed to be different from most examples in the literature and was strongly influenced by substitution on the octalone ring.

  10. Diastereoselectivity in the reduction of bicyclic enones with hindered hydrides

    International Nuclear Information System (INIS)

    Camozzato, Andreza C.; Tenius, Beatriz S. M.; Oliveira, Eduardo R. de; Viegas Junior, Claudio; Victor, Mauricio M.; Silveira, Leandro G. da

    2008-01-01

    Reduction of five substituted octalones employing lithium tri-sec-butylborohydride (L-selectride R ) in THF and ethyl ether led to allylic alcohols with moderate diastereoselectivity. The stereoselectivity of addition of bulky hydrides showed to be different from most examples in the literature and was strongly influenced by substitution on the octalone ring. (author)

  11. Fractal analysis of electrolytically-deposited palladium hydride dendrites

    International Nuclear Information System (INIS)

    Bursill, L.A.; Julin, Peng; Xudong, Fan.

    1990-01-01

    The fractal scaling characteristics of the surface profile of electrolytically-deposited palladium hydride dendritic structures have been obtained using conventional and high resolution transmission electron microscopy. The results are in remarkable agreement with the modified diffusion-limited aggregation model. 19 refs., 3 tabs., 13 figs

  12. Development of transmutation technologies of radioactive waste by actinoid hydride

    International Nuclear Information System (INIS)

    Konashi, Kenji; Matsui, Hideki; Yamawaki, Michio

    2001-01-01

    Two waste treatment methods, geological disposal and transmutation, have been studied. The transmutation method changes long-lived radioactive nuclides to short-lived one or stabilizes them by nuclear transformation. The transmutation by actinoid hydride is exactly alike that transformation method from actinoid disposal waste to Pu fuel. For this object, OMEGA project is processing now. The transmutation is difficult by two causes such as large amount of long-lived radioactive nuclides and not enough development of control technologies of nuclear reaction except atomic reactor. The transmutation using actinoid hydride has merits that the amount of actinoid charged in the target increases and the effect of thermal neutrons on fuel decreases depending on homogeneous transmutation velocity in the target. Development of stable actinoid hydride under the conditions of reactor temperature and irradiation environment is important. The experimental results of U-ZrH 1.6 are shown in this paper. The irradiation experiment using Th hydride has been proceeding. (S.Y.)

  13. Hydrogen and dihydrogen bonding of transition metal hydrides

    International Nuclear Information System (INIS)

    Jacobsen, Heiko

    2008-01-01

    Intermolecular interactions between a prototypical transition metal hydride WH(CO) 2 NO(PH 3 ) 2 and a small proton donor H 2 O have been studied using DFT methodology. The hydride, nitrosyl and carbonyl ligand have been considered as site of protonation. Further, DFT-D calculations in which empirical corrections for the dispersion energy are included, have been carried out. A variety of pure and hybrid density functionals (BP86, PW91, PBE, BLYP, OLYP, B3LYP, B1PW91, PBE0, X3LYP) have been considered, and our calculations indicate the PBE functional and its hybrid variation are well suited for the calculation of transition metal hydride hydrogen and dihydrogen bonding. Dispersive interactions make up for a sizeable portion of the intermolecular interaction, and amount to 20-30% of the bond energy and to 30-40% of the bond enthalpy. An energy decomposition analysis reveals that the H...H bond of transition metal hydrides contains both covalent and electrostatic contributions

  14. Hydrogen and dihydrogen bonding of transition metal hydrides

    Science.gov (United States)

    Jacobsen, Heiko

    2008-04-01

    Intermolecular interactions between a prototypical transition metal hydride WH(CO) 2NO(PH 3) 2 and a small proton donor H 2O have been studied using DFT methodology. The hydride, nitrosyl and carbonyl ligand have been considered as site of protonation. Further, DFT-D calculations in which empirical corrections for the dispersion energy are included, have been carried out. A variety of pure and hybrid density functionals (BP86, PW91, PBE, BLYP, OLYP, B3LYP, B1PW91, PBE0, X3LYP) have been considered, and our calculations indicate the PBE functional and its hybrid variation are well suited for the calculation of transition metal hydride hydrogen and dihydrogen bonding. Dispersive interactions make up for a sizeable portion of the intermolecular interaction, and amount to 20-30% of the bond energy and to 30-40% of the bond enthalpy. An energy decomposition analysis reveals that the H⋯H bond of transition metal hydrides contains both covalent and electrostatic contributions.

  15. Hydrogen and dihydrogen bonding of transition metal hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Jacobsen, Heiko [KemKom, Libellenweg 2, 25917 Leck, Nordfriesland (Germany)], E-mail: jacobsen@kemkom.com

    2008-04-03

    Intermolecular interactions between a prototypical transition metal hydride WH(CO){sub 2}NO(PH{sub 3}){sub 2} and a small proton donor H{sub 2}O have been studied using DFT methodology. The hydride, nitrosyl and carbonyl ligand have been considered as site of protonation. Further, DFT-D calculations in which empirical corrections for the dispersion energy are included, have been carried out. A variety of pure and hybrid density functionals (BP86, PW91, PBE, BLYP, OLYP, B3LYP, B1PW91, PBE0, X3LYP) have been considered, and our calculations indicate the PBE functional and its hybrid variation are well suited for the calculation of transition metal hydride hydrogen and dihydrogen bonding. Dispersive interactions make up for a sizeable portion of the intermolecular interaction, and amount to 20-30% of the bond energy and to 30-40% of the bond enthalpy. An energy decomposition analysis reveals that the H...H bond of transition metal hydrides contains both covalent and electrostatic contributions.

  16. Cascades for hydrogen isotope separation using metal hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Hill, F B; Grzetic, V [Brookhaven National Lab., Upton, NY (USA)

    1983-02-01

    Designs are presented for continuous countercurrent hydrogen isotope separation cascades based on the use of metal hydrides. The cascades are made up of pressure swing adsorption (PSA) or temperature swing adsorption (TSA) stages. The designs were evolved from consideration of previously conducted studies of the separation performance of four types of PSA and TSA processes.

  17. Diffusion model of delayed hydride cracking in zirconium alloys

    NARCIS (Netherlands)

    Shmakov, AA; Kalin, BA; Matvienko, YG; Singh, RN; De, PK

    2004-01-01

    We develop a method for the evaluation of the rate of delayed hydride cracking in zirconium alloys. The model is based on the stationary solution of the phenomenological diffusion equation and the detailed analysis of the distribution of hydrostatic stresses in the plane of a sharp tensile crack.

  18. Hydrogen Storage in Porous Materials and Magnesium Hydrides

    NARCIS (Netherlands)

    Grzech, A.

    2013-01-01

    In this thesis representatives of two different types of materials for potential hydrogen storage application are presented. Usage of either nanoporous materials or metal hydrides has both operational advantages and disadvantages. A main objective of this thesis is to characterize the hydrogen

  19. The Properties of Some Simple Covalent Hydrides: An Ab Initio ...

    African Journals Online (AJOL)

    Some properties of the monomeric binary hydrides of the elements of the first two rows of the periodic table have been determined using ab initio molecular orbital theory. The properties in question are the energetic, structural, electronic, topological and vibrational characteristics. In general, a gradual convergence towards ...

  20. Hanford Waste Vitrification Plant full-scale feed preparation testing with water and process simulant slurries

    International Nuclear Information System (INIS)

    Gaskill, J.R.; Larson, D.E.; Abrigo, G.P.

    1996-03-01

    The Hanford Waste Vitrification Plant was intended to convert selected, pretreated defense high-level waste and transuranic waste from the Hanford Site into a borosilicate glass. A full-scale testing program was conducted with nonradioactive waste simulants to develop information for process and equipment design of the feed-preparation system. The equipment systems tested included the Slurry Receipt and Adjustment Tank, Slurry Mix Evaporator, and Melter-Feed Tank. The areas of data generation included heat transfer (boiling, heating, and cooling), slurry mixing, slurry pumping and transport, slurry sampling, and process chemistry. 13 refs., 129 figs., 68 tabs

  1. Sorption of 17b-Estradiol to Pig Slurry Separates and Soil in the Soil-Slurry Environment

    DEFF Research Database (Denmark)

    Amin, Mostofa; Petersen, Søren O; Lægdsmand, Mette

    2012-01-01

    to agricultural soils, to different size fractions of pig slurry separates, and to soils amended with each size fraction to simulate conditions in the soil–slurry environment. A crude fiber fraction (SS1) was prepared by sieving (solids removed by an on-farm separation process. Three other size...... fractions (SS2 > SS3 > SS4) were prepared from the liquid fraction of the separated slurry by sedimentation and centrifugation. Sorption experiments were conducted in 0.01 mol L−1 CaCl2 and in natural pig urine matrix. Sorption in 0.01 mol L−1 CaCl2 was higher than that in pig urine for all solids used....... Sorption of E2 to soil increased with its organic carbon content for both liquid phases. The solid–liquid partition coefficients of slurry separates were 10 to 30 times higher than those of soils, but the organoic carbon normalized partition coefficient values, reflecting sorption per unit organic carbon...

  2. Activation and discharge kinetics of metal hydride electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Johnsen, Stein Egil

    2003-07-01

    Potential step chronoamperometry and Electrochemical Impedance Spectroscopy (eis) measurements were performed on single metal hydride particles. For the {alpha}-phase, the bulk diffusion coefficient and the absorption/adsorption rate parameters were determined. Materials produced by atomisation, melt spinning and conventional casting were investigated. The melt spun and conventional cast materials were identical and the atomised material similar in composition. The particles from the cast and the melt spun material were shaped like parallelepipeds. A corresponding equation, for this geometry, for diffusion coupled to an absorption/adsorption reaction was developed. It was found that materials produced by melt spinning exhibited lower bulk diffusion (1.7E-14 m2/s) and absorption/adsorption reaction rate (1.0E-8 m/s), compared to materials produced by conventionally casting (1.1E-13 m2/s and 5.5E-8 m/s respectively). In addition, the influence of particle active surface and relative diffusion length were discussed. It was concluded that there are uncertainties connected to these properties, which may explain the large distribution in the kinetic parameters measured on metal hydride particles. Activation of metal hydride forming materials has been studied and an activation procedure, for porous electrodes, was investigated. Cathodic polarisation of the electrode during a hot alkaline surface treatment gave the maximum discharge capacity on the first discharge of the electrode. The studied materials were produced by gas atomisation and the spherical shape was retained during the activation. Both an AB{sub 5} and an AB{sub 2} alloy was successfully activated and discharge rate properties determined. The AB{sub 2} material showed a higher maximum discharge capacity, but poor rate properties, compared to the AB{sub 5} material. Reduction of surface oxides, and at the same time protection against corrosion of active metallic nickel, can explain the satisfying results of

  3. PROGRESS TOWARDS MODELING OF FISCHER TROPSCH SYNTHESIS IN A SLURRY BUBBLE COLUMN REACTOR

    Energy Technology Data Exchange (ETDEWEB)

    Donna Post Guillen; Tami Grimmett; Anastasia M. Gandrik; Steven P. Antal

    2010-11-01

    The Hybrid Energy Systems Testing (HYTEST) Laboratory is being established at the Idaho National Laboratory to develop and test hybrid energy systems with the principal objective to safeguard U.S. Energy Security by reducing dependence on foreign petroleum. A central component of the HYTEST is the slurry bubble column reactor (SBCR) in which the gas-to-liquid reactions will be performed to synthesize transportation fuels using the Fischer Tropsch (FT) process. SBCRs are cylindrical vessels in which gaseous reactants (for example, synthesis gas or syngas) is sparged into a slurry of liquid reaction products and finely dispersed catalyst particles. The catalyst particles are suspended in the slurry by the rising gas bubbles and serve to promote the chemical reaction that converts syngas to a spectrum of longer chain hydrocarbon products, which can be upgraded to gasoline, diesel or jet fuel. These SBCRs operate in the churn-turbulent flow regime which is characterized by complex hydrodynamics, coupled with reacting flow chemistry and heat transfer, that effect reactor performance. The purpose of this work is to develop a computational multiphase fluid dynamic (CMFD) model to aid in understanding the physico-chemical processes occurring in the SBCR. Our team is developing a robust methodology to couple reaction kinetics and mass transfer into a four-field model (consisting of the bulk liquid, small bubbles, large bubbles and solid catalyst particles) that includes twelve species: (1) CO reactant, (2) H2 reactant, (3) hydrocarbon product, and (4) H2O product in small bubbles, large bubbles, and the bulk fluid. Properties of the hydrocarbon product were specified by vapor liquid equilibrium calculations. The absorption and kinetic models, specifically changes in species concentrations, have been incorporated into the mass continuity equation. The reaction rate is determined based on the macrokinetic model for a cobalt catalyst developed by Yates and Satterfield [1]. The

  4. Leaf absorption of atmospheric ammonia emitted from pig slurry applied beneath the canopy of winter wheat

    International Nuclear Information System (INIS)

    Gjedde Sommer, S.; Jensen, E.S.; Kofoed Schjoerring, J.

    1993-01-01

    Absorption of volatilized ammonia after application of slurry onto the soil surface (sand) between rows of a wheat crop was studied in two experiments. The slurry was labelled with 15 N-NH 4 . During seven days the accumulated gaseous N loss from the slurry varied from 6.9 to 11.1 g N m -2 . In April ammonia losses from slurry applied beneath a 5 cm high wheat crop were equal to losses from slurry applied to a fallow, but 2.2% of the lost atmospheric ammonia was taken up by the leaves. In May ammonia loss from slurry applied between the rows of a 43 cm high crop was reduced by 6% compared to the loss from fallow, because of a reduced transfer of ammonia from the slurry to the air. Of the emitted ammonia 3.3% was absorbed by the canopy. (au)

  5. Transport of Cryptosporidium parvum oocysts in soil columns following applications of raw and separated liquid slurries.

    Science.gov (United States)

    Petersen, Heidi H; Enemark, Heidi L; Olsen, Annette; Amin, M G Mostofa; Dalsgaard, Anders

    2012-09-01

    The potential for the transport of viable Cryptosporidium parvum oocysts through soil to land drains and groundwater was studied using simulated rainfall and intact soil columns which were applied raw slurry or separated liquid slurry. Following irrigation and weekly samplings over a 4-week period, C. parvum oocysts were detected from all soil columns regardless of slurry type and application method, although recovery rates were low (vertical distribution of oocysts, with more oocysts recovered from soil columns added liquid slurry irrespective of the irrigation status. Further studies are needed to determine the effectiveness of different slurry separation technologies to remove oocysts and other pathogens, as well as whether the application of separated liquid slurry to agricultural land may represent higher risks for groundwater contamination compared to application of raw slurry.

  6. A new cement slurry modified with chitosan/alginate interpenetrating networks and hydroxyapatite: structural characteristics after long-term contact with hyper-saline produced water from oil well operations

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Ivory Marcos Gomes dos; Santos, Danilo Oliveira; Cestari, Antonio Reinaldo, E-mail: ivorymarcos@hotmail.com, E-mail: danilo.quimico@yahoo.com.br, E-mail: rcestari@gmail.com [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Departamento de Ciencia dos Materiais; Ribeiro, Joenesson Filip Santos, E-mail: joenesson.joe@hotmail.com [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Lab, Materiais e Calorimetria; Alves, Jose do Patrocinio Hora; Ferreira, Angelica Baganha, E-mail: jphalves@uol.com.br, E-mail: angelica.bferreira@itps.se.gov.br [Instituto Tecnologico e de Pesquisas do Estado de Sergipe (ITPS), Aracaju, SE (Brazil)

    2017-01-15

    Oil is an important source of energy, mainly in developing countries. Important research has been conducted to find cementing procedures that guarantee safe and cost-effective oil exploration below pre-salt layers. This work aimed to make a new cement paste with cement, seawater, silica, biopolymers (chitosan and sodium alginate) and hydroxyapatite (HA), found in nature. For comparison purposes, slurry without additives was prepared and characterized. The HA used was extracted from fish scales (Cynoscion acoupa) in optimized condition NaOH concentration, temperature and reaction time. Both slurry were prepared with ratios water/cement (w/c) and silica/cement (s/c) equal to 0.50 and 0.35, respectively. The new cement slurry was obtained with proportions of 5% of each biopolymer and HA with respect to the total weight of the cement. In the immersion tests, specimens were immersed in samples of hyper production of saline water by 35°C for 15 days. Thereafter, they were washed, dried and its surface layers were scraped. Before, the resulting materials were characterized. The values of the ratios Ca/Si of new cement slurry (3.38 ± 0.06) were superior compared to standard (2.58 ± 0.05). The new slurry had high thermal stability and low amounts of small crystallite-type portlandite (35.70 nm). Conversely, a slurry standard formed larger crystals of about 50.3 nm. Significantly, after continuous long-term contact of both slurries with hyper-saline produced water from oil well fields operations, in comparison with standard slurry structural characteristics, the new slurry has practically maintained its pristine chemical structure, as well as has shown crystallite-type particles of NaCl and Friedel’s/Kuzel’s salts with lower proportion. The presence of the biopolymers and HA has driven the improved the self-healing properties observed in the new cement slurry. In this first study, the new slurry has shown adequate characteristics to contribute to cost effective and

  7. A new cement slurry modified with chitosan/alginate interpenetrating networks and hydroxyapatite: structural characteristics after long-term contact with hyper-saline produced water from oil well operations

    International Nuclear Information System (INIS)

    Santos, Ivory Marcos Gomes dos; Santos, Danilo Oliveira; Cestari, Antonio Reinaldo

    2017-01-01

    Oil is an important source of energy, mainly in developing countries. Important research has been conducted to find cementing procedures that guarantee safe and cost-effective oil exploration below pre-salt layers. This work aimed to make a new cement paste with cement, seawater, silica, biopolymers (chitosan and sodium alginate) and hydroxyapatite (HA), found in nature. For comparison purposes, slurry without additives was prepared and characterized. The HA used was extracted from fish scales (Cynoscion acoupa) in optimized condition NaOH concentration, temperature and reaction time. Both slurry were prepared with ratios water/cement (w/c) and silica/cement (s/c) equal to 0.50 and 0.35, respectively. The new cement slurry was obtained with proportions of 5% of each biopolymer and HA with respect to the total weight of the cement. In the immersion tests, specimens were immersed in samples of hyper production of saline water by 35°C for 15 days. Thereafter, they were washed, dried and its surface layers were scraped. Before, the resulting materials were characterized. The values of the ratios Ca/Si of new cement slurry (3.38 ± 0.06) were superior compared to standard (2.58 ± 0.05). The new slurry had high thermal stability and low amounts of small crystallite-type portlandite (35.70 nm). Conversely, a slurry standard formed larger crystals of about 50.3 nm. Significantly, after continuous long-term contact of both slurries with hyper-saline produced water from oil well fields operations, in comparison with standard slurry structural characteristics, the new slurry has practically maintained its pristine chemical structure, as well as has shown crystallite-type particles of NaCl and Friedel’s/Kuzel’s salts with lower proportion. The presence of the biopolymers and HA has driven the improved the self-healing properties observed in the new cement slurry. In this first study, the new slurry has shown adequate characteristics to contribute to cost effective and

  8. Nutrient losses from cattle co-digestate slurry during storage

    Directory of Open Access Journals (Sweden)

    Francesca Perazzolo

    2016-06-01

    Full Text Available Among environmental issues related to intensive livestock activity, emissions to air from manure management are of increasing concern. Thus the knowledge of the effect of treatment application on subsequent emissions from manure is required to assess the environment impact of management solutions. This work addresses the effect of anaerobic digestion and phase separation on emissions during storage by studying nitrogen losses from lab-scale stores and field pilot-scale stores of a co-digestate cattle slurry and its respective separated fractions. Lab-scale experiment was carried in temperature-controlled room where each fraction (untreated, separated liquid and separated solid was stored in duplicate for a period of 32 days in 30 L vessel. Pilot-scale experiment was carried out both during the cold season and during warm season for 90 days of storage. In both experimentations samples of the manure were analysed periodically for total Kjeldahl nitrogen (TKN, total ammonia nitrogen, dry matter and volatile solids and pH. These analyses allow estimating nitrogen losses in different storage conditions. Effects of mechanical separation and season were assessed by ANOVA (Wilcoxon test, P<0.05. In temperature controlled conditions nitrogen losses measured account for 13% and 26% of TKN for unseparated and separated slurries respectively. In field conditions during cold season nutrient losses were limited. On average unseparated and separated slurries lost respectively 6.8% and 12.6% of their initial TKN content. Much higher were the TKN losses from the slurries examined in warm season where losses raised up to 40% of the initial TKN content. Generally mechanical separation increases nutrient losses, but the differences were not significant in field conditions. The results highlighted that nutrient losses, in particular the nitrogen ones, can be considerable especially during summer storage. The latter, in case of separated slurries, are mainly related

  9. Hydride redistribution and crack growth in Zr-2.5 wt.% Nb stressed in torsion

    International Nuclear Information System (INIS)

    Puls, M.P.; Rogowski, A.J.

    1980-11-01

    The effect of applied shear stresses on zirconium hydride solubility in a zirconium alloy was investigated. Recent studies have shown that zirconium hydride precipiates probably nucleate and grow by means of a shear transformation mechanism. It is postulated that these transformation shear strains can interact with applied shear stress gradients in the same way that the dilatational strains can interact with a dilatational stress gradient, providing a driving force for hydride accumulation, hydride embrittlement and crack propagation. To test this proposition, crack growth experiments were carried out under torsional loading conditions on hydrided, round notched bar specimens of cold-worked Zr-2.5 wt.% Nb cut from Pickering-type pressure tube material. Postmortem metallographic examination of the hydride distribution in these samples showed that, in many cases, the hydrides appeared to have reoriented in response to the applied shear stress and that hydride accumulation at the notch tip had occurred. However, except in a few cases, the rate of accumulation of reoriented hydrides at the notch tip due to applied shear stresses was much less than the rate due to corresponding applied uniaxial stresss. Moreover, the process in shear appears to be more sensitive to the inital hydride size. Attempts to elucidate the fracture mechanism by fractographic examination using scanning and replica transmission electron microscopy proved to be inconclusive because of smearing of the fracture face. (auth)

  10. High pressure hydriding of sponge-Zr in steam-hydrogen mixtures

    International Nuclear Information System (INIS)

    Kim, Y.S.

    1997-01-01

    Hydriding kinetics of thin sponge-Zr layers metallurgically bonded to a Zircaloy disk has been studied by thermogravimetry in the temperature range 350-400 C in 7 MPa hydrogen-steam mixtures. Some specimens were prefilmed with a thin oxide layer prior to exposure to the reactant gas; all were coated with a thin layer of gold to avoid premature reaction at edges. Two types of hydriding were observed in prefilmed specimens, viz., a slow hydrogen absorption process that precedes an accelerated (massive) hydriding. At 7 MPa total pressure, the critical ratio of H 2 /H 2 O above which massive hydriding occurs at 400 C is ∝200. The critical H 2 /H 2 O ratio is shifted to ∝2.5 x 10 3 at 350 C. The slow hydriding process occurs only when conditions for hydriding and oxidation are approximately equally favorable. Based on maximum weight gain, the specimen is completely converted to δ-ZrH 2 by massive hydriding in ∝5 h at a hydriding rate of ∝10 -6 mol H/cm 2 s. Incubation times of 10-20 h prior to the onset of massive hydriding increases with prefilm oxide thickness in the range of 0-10 μm. By changing to a steam-enriched gas, massive hydriding that initially started in a steam-starved condition was arrested by re-formation of a protective oxide scale. (orig.)

  11. RHEOLOGICAL AND ELEMENTAL ANALYSES OF SIMULANT SB5 SLURRY MIX EVAPORATOR-MELTER FEED TANK SLURRIES

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, A.

    2010-02-08

    The Defense Waste Processing Facility (DWPF) will complete Sludge Batch 5 (SB5) processing in fiscal year 2010. DWPF has experienced multiple feed stoppages for the SB5 Melter Feed Tank (MFT) due to clogs. Melter throughput is decreased not only due to the feed stoppage, but also because dilution of the feed by addition of prime water (about 60 gallons), which is required to restart the MFT pump. SB5 conditions are different from previous batches in one respect: pH of the Slurry Mix Evaporator (SME) product (9 for SB5 vs. 7 for SB4). Since a higher pH could cause gel formation, due in part to greater leaching from the glass frit into the supernate, SRNL studies were undertaken to check this hypothesis. The clogging issue is addressed by this simulant work, requested via a technical task request from DWPF. The experiments were conducted at Aiken County Technology Laboratory (ACTL) wherein a non-radioactive simulant consisting of SB5 Sludge Receipt and Adjustment Tank (SRAT) product simulant and frit was subjected to a 30 hour SME cycle at two different pH levels, 7.5 and 10; the boiling was completed over a period of six days. Rheology and supernate elemental composition measurements were conducted. The caustic run exhibited foaming once, after 30 minutes of boiling. It was expected that caustic boiling would exhibit a greater leaching rate, which could cause formation of sodium aluminosilicate and would allow gel formation to increase the thickness of the simulant. Xray Diffraction (XRD) measurements of the simulant did not detect crystalline sodium aluminosilicate, a possible gel formation species. Instead, it was observed that caustic conditions, but not necessarily boiling time, induced greater thickness, but lowered the leach rate. Leaching consists of the formation of metal hydroxides from the oxides, formation of boric acid from the boron oxide, and dissolution of SiO{sub 2}, the major frit component. It is likely that the observed precipitation of Mg

  12. A computational study on the hydrogen adsorption capacity of various lithium-doped boron hydrides.

    Science.gov (United States)

    Pan, Sudip; Giri, Santanab; Chattaraj, Pratim K

    2012-02-05

    An aromatic boron hydride B(3)H(3)(2-) and its various Li/Li(+) doped isomers have been studied at the B3LYP/6-311+G(d) and M06/6-311+G(d) levels of theory to assess their hydrogen storage potential. Different types of interaction energies, reaction enthalpies and reaction electrophilicities associated with the hydrogen adsorption process suggest that B(3)H(3)(2-) itself and some of its Li-decorated analogues may turn out to be effective hydrogen storage material. Nucleus independent chemical shift and conceptual density functional theory based reactivity descriptors lend additional support. The temperature-pressure phase diagram identifies the temperature-pressure zone where the reaction Gibbs free energy for the hydrogen adsorption is negative making it a thermodynamically feasible process. Copyright © 2011 Wiley Periodicals, Inc.

  13. Reviews on the Japanese Patent Applications Regarding Nickel/Metal Hydride Batteries

    Directory of Open Access Journals (Sweden)

    Taihei Ouchi

    2016-06-01

    Full Text Available The Japanese Patent Applications filed on the topic of nickel/metal hydride (Ni/MH batteries have been reviewed. Patent applications filed by the top nine battery manufacturers (Matsushita, Sanyo, Hitachi Maxell, Yuasa, Toshiba, FDK, Furukawa, Japan Storage, and Shin-kobe, five component suppliers (Tanaka, Mitsui, Santoku, Japan Metals & Chemicals Co. (JMC, and Shin-Etsu, and three research institutes (Industrial Research Institute (ISI, Agency of Industrial Science and Technology (AIST, and Toyota R & D were chosen as the main subjects for this review, based on their production volume and contribution to the field. By reviewing these patent applications, we can have a clear picture of the technology development in the Japanese battery industry. These patent applications also provide insights, know-how, and future directions for engineers and scientists working in the rechargeable battery field.

  14. Synthesis, characterization, and reactivity of nickel hydride complexes containing 2,6-C6H3(CH2PR2)2 (R = tBu, cHex, and iPr) pincer ligands.

    Science.gov (United States)

    Boro, Brian J; Duesler, Eileen N; Goldberg, Karen I; Kemp, Richard A

    2009-06-15

    The syntheses and full characterization of nickel hydrides containing the PCP "pincer"-type ligand, where PCP = 2,6-C(6)H(3)(CH(2)PR(2))(2) (R = tBu, cHex, and iPr), are reported. These Ni-H complexes are prepared by the conversion of ((R)PCP)NiCl precursors into the corresponding nickel hydrides by use of appropriate hydride donors. Surprisingly, although the ((R)PCP)NiCl precursors are quite similar chemically, the conversions to the hydrides were not straightforward and required different hydride reagents to provide analytically pure products. While NaBH(4) was effective in the preparation of pure ((tBu)PCP)NiH, Super-Hydride solution (LiEt(3)BH in THF) was required to prepare either ((cHex)PCP)NiH or ((iPr)PCP)NiH. Attempts to prepare a Ni-H from ((Ph)PCP)NiCl with a variety of hydride reagents yielded only the free ligand as an identifiable product. Two of the derivatives, tBu and cHex, have also been subjected to single crystal X-ray analysis. The solid-state structures each showed a classic, near-square planar arrangement for Ni in which the PCP ligand occupied three meridional ligand points with the Ni-H trans to the Ni-C bond. The resulting Ni-H bond lengths were 1.42(3) and 1.55(2) A for the tBu and cHex derivatives, respectively.

  15. Tank Waste Transport Stability: Summary of Slurry and Salt-Solution Studies for FY 2001

    Energy Technology Data Exchange (ETDEWEB)

    Welch, T.D.

    2002-06-07

    Despite over 50 years of experience in transporting radioactive tank wastes to and from equipment and tanks at the Department of Energy's Hanford, Savannah River, and Oak Ridge sites, waste slurry transfer pipelines and process piping become plugged on occasion. At Hanford, several tank farm pipelines are no longer in service because of plugs. At Savannah River, solid deposits in the outlet line of the 2H evaporator have resulted in an unplanned extended downtime. Although waste transfer criteria and guidelines intended to prevent pipeline plugging are in place, they are not always adequate. To avoid pipeline plugging in the future, other factors that are not currently embodied in the transfer criteria may need to be considered. The work summarized here is being conducted to develop a better understanding of the chemical and waste flow dynamics during waste transfer. The goal is to eliminate pipeline plugs by improving analysis and engineering tools in the field that incorporate this understanding.

  16. Effects of Anaerobically Digested Slurry on Meloidogyne incognita and Pratylenchus penetrans in Tomato and Radish Production

    International Nuclear Information System (INIS)

    Min, Y.Y; Toyota, K; Sato, E; Takada, A

    2011-01-01

    Since effective disposable way of anaerobically digested biogas slurry is expected, ADS was applied to soil to evaluate its effects on nematode damage. Damage index of tomato by root-knot nematode was significantly (P 4 + -N kg -1 ) than that in those with chemical fertilizer and control (no ADS). ADS was applied into radish cultivated fields infested with the root-lesion nematode: a single (100 kg NH 4 + -N ha -1 ) in 2007 and 2008 and multiple applications (25, 50, 25 kg NH 4 + -N ha -1 soil) in 2009. Damage to radish was 30% and 50% lower in ADS-treated fields than that in the control in 2007 and 2009, respectively, although not in 2008. These results suggest that application of ADS to fields might be feasible for mitigating nematode damage, but the rate and timing should be considered further for the best application way.

  17. Enhanced methane production from pig slurry with pulsed electric field pre-treatment.

    Science.gov (United States)

    Safavi, Seyedeh Masoumeh; Unnthorsson, Runar

    2018-02-01

    Intensive amount of manure produced in pig breeding sectors represents negative impact on the environment and requires optimal management. Anaerobic digestion as a well-known manure management process was optimized in this experimental study by pulsed electric field (PEF) pre-treatment. The effect of PEF on methane production was investigated at three different intensities (15, 30 and 50 kWh/m 3 ). The results indicate that the methane production and chemical oxygen demand (COD) removal was improved by continuous escalation of applied intensity, up to 50 kWh/m 3 . In comparison with untreated slurry, methane production and COD removal were increased up to 58% and 44%, respectively.

  18. Preparation of coal slurries deposited in ground settling ponds

    Directory of Open Access Journals (Sweden)

    Wiesław Blaschke

    2005-11-01

    Full Text Available As a result of the hard coal washing process, considerable quantities of coal slimes are generated. They belong to grain size classes below 1, 0 mm (with the majority of grains below 0,035 mm and are often sold in order to prepare blends for the power generation. It is assessed that in Poland about 11 mln tons of such slimes were deposited. The slimes of a low ash content can be exploited and sold. The slime of high ash content must be washed. In Poland there is one coal preparation plant for slurries. The article describes the technology and presents the results of a simplified economic analysis of exploitation of the slurries and their washing.

  19. Design of a new abrasive slurry jet generator

    Science.gov (United States)

    Wang, F. C.; Shi, L. L.; Guo, C. W.

    2017-12-01

    With the advantages of a low system working pressure, good jet convergence and high cutting quality, abrasive slurry jet (ASJ) has broad application prospects in material cutting and equipment cleaning. Considering that the generator plays a crucial role in ASJ system, the paper designed a new type ASJ generator using an electric oil pump, a separate plunger cylinder, and a spring energized seal. According to the determining of structure shape, size and seal type, a new ASJ generator has been manufactured out and tested by a series of experiments. The new generator separates the abrasive slurry from the dynamic hydraulic oil, which can improve the service life of the ASJ system. And the new ASJ system can reach 40 MPa and has good performance in jet convergence, which deserves to popularization and application in materials machining.

  20. Analysis of barium hydroxide and calcium hydroxide slurry carbonation reactors

    International Nuclear Information System (INIS)

    Patch, K.D.; Hart, R.P.; Schumacher, W.A.

    1980-05-01

    The removal of CO 2 from air was investigated by using a continuous-agitated-slurry carbonation reactor containing either barium hydroxide [Ba(OH) 2 ] or calcium hydroxide [Ca(OH) 2 ]. Such a process would be applied to scrub 14 CO 2 from stack gases at nuclear-fuel reprocessing plants. Decontamination factors were characterized for reactor conditions which could alter hydrodynamic behavior. An attempt was made to characterize reactor performance with models assuming both plug flow and various degrees of backmixing in the gas phase. The Ba(OH) 2 slurry enabled increased conversion, but apparently the process was controlled under some conditions by phenomena differing from those observed for carbonation by Ca(OH) 2 . Overall reaction mechanisms are postulated