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Sample records for sand-water slurry erosion

  1. Slurry Erosion Behavior of Destabilized and Deep Cryogenically Treated Cr-Mn-Cu White Cast Irons

    Directory of Open Access Journals (Sweden)

    S. Gupta

    2016-12-01

    Full Text Available The effects of destabilization treatment and destabilization followed by cryogenic treatment have been evaluated on the microstructural evolution and sand-water slurry erosion behavior of Cr-Mn-Cu white cast irons. The phase transformations after the destabilization and cryotreatment have been characterized by bulk hardness measurement, optical and scanning electron microscopy, x-ray diffraction analysis. The static corrosion rate has been measured in tap water (with pH=7 and the erosion-corrosion behavior has been studied by slurry pot tester using sand-water slurry. The test results indicate that the cryogenic treatment has a significant effect in minimizing the as-cast retained austenite content and transforming into martensitic and bainitic matrix embedded with ultra-fine M7C3 alloy carbides. In contrast, by conventional destabilization treatment retained austenite in the matrix are not fully eliminated. The slurry erosive wear resistance has been compared with reference to destabilized and cryotreated high chromium iron samples which are commonly employed for such applications. The cryotreated Cr-Mn-Cu irons have exhibited a comparable erosive wear performance to those of high chromium irons. Higher hardness combined with improved corrosion resistance result in better slurry erosion resistance.

  2. 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.

  3. Combined slurry and cavitation erosion resistance of surface modified SS410 stainless steel

    Science.gov (United States)

    Amarendra, H. J.; Pratap, M. S.; Karthik, S.; Punitha Kumara, M. S.; Rajath, H. C.; Ranjith, H.; Shubhatunga, S. V.

    2018-03-01

    Slurry erosion and combined slurry and cavitation erosion resistance of thermal spray coatings are studied and compared with the as-received martensitic stainless steel material. 70Ni-Cr coatings are deposited on SS 410 material through plasma thermal spray process. The synergy effect of the combined slurry and cavitation erosion resistance of plasma thermal spray coatings were investigated in a slurry pot tester in the presence of bluff bodies known as Cavitation Inducers. Results showed the combined slurry and cavitation erosion resistance of martensitic stainless steel - 410 can be improved by plasma thermal spray coating. It is observed that the plasma spray coated specimens are better erosion resistant than the as- received material, subjected to erosion test under similar conditions. As-received and the surface modified steels are mechanically characterized for its hardness, bending. Morphological studies are conducted through scanning electron microscope.

  4. Study of the Parametric Performance of Solid Particle Erosion Wear under the Slurry Pot Test Rig

    Directory of Open Access Journals (Sweden)

    S.R. More

    2017-12-01

    Full Text Available Stainless Steel (SS 304 is commonly used material for slurry handling applications like pipelines, valves, pumps and other equipment's. Slurry erosion wear is a common problem in many engineering applications like process industry, thermal and hydraulic power plants and slurry handling equipments. In this paper, experimental investigation of the influence of solid particle size, impact velocity, impact angle and solid concentration parameters in slurry erosion wear behavior of SS 304 using slurry pot test rig. In this study the design of experiments was considered using Taguchi technique. A comparison has been made for the experimental and Taguchi technique results. The erosion wear morphology was studied using micro-graph obtained by scanning electron microscope (SEM analysis. At shallow impact angle 30°, the material removal pattern was observed in the form of micro displacing, scratching and ploughing with plastic deformation of the material. At 60° impact angle, mixed type of micro indentations and pitting action is observed. At normal impact angle 90°, the material removal pattern was observed in form of indentation and rounded lips. It is found that particle velocity was the most influence factor than impact angle, size and solid concentration. From this investigation, it can be concluded that the slurry erosion wear is minimized by controlling the slurry flow velocity which improves the service life of the slurry handling equipments. From the comparison of experimental and Taguchi experimental design results it is found that the percentage deviation was very small with a higher correlation coefficient (r2 0.987 which is agreeable.

  5. Erosion Evaluation of a Slurry Mixer Tank with Computational Fluid Dynamics Methods

    International Nuclear Information System (INIS)

    Lee, S

    2006-01-01

    This paper discusses the use of computational fluid dynamics (CFD) methods to understand and characterize erosion of the floor and internal structures in the slurry mixing vessels in the Defense Waste Processing Facility. An initial literature survey helped identify the principal drivers of erosion for a solids laden fluid: the solids content of the working fluid, the regions of recirculation and particle impact with the walls, and the regions of high wall shear. A series of CFD analyses was performed to characterize slurry-flow profiles, wall shear, and particle impingement distributions in key components such as coil restraints and the vessel floor. The calculations showed that the primary locations of high erosion resulting from abrasion were at the leading edge of the coil guide, the tank floor below the insert plate of the coil guide support, and the upstream lead-in plate. These modeling results based on the calculated high shear regions were in excellent agreement with the observed erosion sites in both location and the degree of erosion. Loss of the leading edge of the coil guide due to the erosion damage during the slurry mixing operation did not affect the erosion patterns on the tank floor. Calculations for a lower impeller speed showed similar erosion patterns but significantly reduced wall shear stresses

  6. CFD simulation and experimental analysis of erosion in a slurry tank test rig

    Directory of Open Access Journals (Sweden)

    Bart Hans-Jörg

    2013-04-01

    Full Text Available Erosion occurring in equipment dealing with liquid-solid mixtures such as pipeline parts, slurry pumps, liquid-solid stirred reactors and slurry mixers in various industrial applications results in operational failure and economic costs. A slurry erosion tank test rig is designed and was built to investigate the erosion rates of materials and the influencing parameters such as flow velocity and turbulence, flow angle, solid particle concentration, particles size distribution, hardness and target material properties on the material loss and erosion profiles. In the present study, a computational fluid dynamics (CFD tool is used to simulate the erosion rate of sample plates in the liquid-solid slurry mixture in a cylindrical tank. The predictions were made in a steady state and also transient manner, applying the flow at the room temperature and using water and sand as liquid and solid phases, respectively. The multiple reference frame method (MRF is applied to simulate the flow behavior and liquid-solid interactions in the slurry tank test rig. The MRF method is used since it is less demanding than sliding mesh method (SM and gives satisfactory results. The computational domain is divided into three regions: a rotational or MRF zone containing the mixer, a rotational zone (MRF containing the erosion plates and a static zone (outer liquid zone. It is observed that changing the MRF zone diameter and height causes a very low impact on the results. The simulated results were obtained for two kinds of hard metals namely stainless steel and ST-50 under some various operating conditions and are found in good agreement with the experimental results.

  7. Experimental and numerical studies on laser-based powder deposition of slurry erosion resistant materials

    Science.gov (United States)

    Balu, Prabu

    Slurry erosion (the removal of material caused by the randomly moving high velocity liquid-solid particle mixture) is a serious issue in crude oil drilling, mining, turbines, rocket nozzles, pumps, and boiler tubes that causes excessive downtime and high operating costs as a result of premature part failure. The goal of this research is to enhance the service life of high-value components subjected to slurry erosion by utilizing the concept of functionally graded metal-ceramic composite material (FGMCCM) in which the favorable properties of metal (toughness, ductility, etc.) and ceramic (hardness) are tailored smoothly to improve erosion resistance. Among the potential manufacturing processes, such as the laser-based powder deposition (LBPD), the plasma transferred arc (PTA), and the thermal spray the LBPD process offers good composition and microstructure control with a high deposition rate in producing the FGMCCM. This research focuses on the development of nickel-tungsten carbide (Ni-WC) based FGMCCM using the LBPD process for applications the above mentioned. The LBPD of Ni-WC involves the introduction of Ni and WC powder particle by an inert gas into the laser-formed molten pool at the substrate via nozzles. The LBPD of Ni-WC includes complex multi-physical interactions between the laser beam, Ni-WC powder, substrate, and carrier and shielding gases that are governed by a number of process variables such as laser power, scanning speed, and powder flow rate. In order to develop the best Ni-WC based slurry erosion resistant material using the LBPD process, the following challenges associated with the fabrication and the performance evaluation need to be addressed: 1) flow behavior of the Ni-WC powder and its interaction with the laser, 2) the effect of the process variables, the material compositions, and the thermo-physical properties on thermal cycles, temperature gradient, cooling rate, and residual stress formation within the material and the subsequent

  8. The Effect of pH on Slurry Erosion-Corrosion of Tungsten Carbide Overlays Alloyed with Ru

    Science.gov (United States)

    Nelwalani, Ndivhuwo B.; van der Merwe, Josias W.

    2018-02-01

    The aim of the study was to determine the effect of Ru additions to WC-Fe overlays when exposed to low pH slurry erosion conditions. These overlays were applied through Plasma Transferred Arc, and the original bulk Ru powder concentrations varied from 0.5 to 5 wt.%. A slurry jet impingement erosion-corrosion test rig was used to evaluate wear, and electrochemical measurements were performed to characterize the corrosion properties. The slurry mixtures contained silica sand and synthetic mine water. The pH was varied between 3 and 6.5 for the slurry erosion tests and lowered further for the corrosion characterization. Samples were examined optically and with a scanning electron microscope using energy-dispersive x-ray spectroscopy. X-ray diffraction analysis was used to determine the phases present. For the slurry erosion-corrosion results at the pH of 6.5, addition of Ru did not show a decrease in erosion-corrosion rates. However, when the pH was decreased to 3, by the addition of HCl, Ru improved the resistance. From the electrochemistry, it was also clear that Ru additions improved the corrosion resistance, but more than 1 wt.% Ru was required. At very low pH levels, the presence of Ru was not able to prevent corrosion.

  9. Slurry Erosion Studies on Surface Modified 13Cr-4Ni Steels: Effect of Angle of Impingement and Particle Size

    Science.gov (United States)

    Manisekaran, T.; Kamaraj, M.; Sharrif, S. M.; Joshi, S. V.

    2007-10-01

    Hydroturbine steels, such as 13Cr-4Ni martensitic steels, are generally subjected to heavy-erosive wear and loss of efficiency due to solid particulate entrainment in the water. Surface-modified steels have proven to give better performance in terms of erosive wear resistance. In the present study, an attempt is made to investigate the effect of angle of impingement and particle size on slurry-jet erosion behavior of pulsed plasma nitrided and laser hardened 13Cr-4Ni steels. Laser hardening process has shown good performance at all angles of impingement due to martensitic transformation of retained austenite. Plastic deformation mode of material removal was also an evident feature of all laser-hardened surface damage locations. However, pulsed-plasma nitrided steels have exhibited chip formation and micro-cutting mode of erosive wear. Erosion with 150-300 μm size was twice compared to 150 μm size slurry particulates.

  10. Slurry Erosion Performance of Ni-Al2O3 Based Thermal-Sprayed Coatings: Effect of Angle of Impingement

    Science.gov (United States)

    Grewal, H. S.; Agrawal, Anupam; Singh, H.; Shollock, B. A.

    2014-02-01

    In this paper, slurry erosion performance of high velocity flame-sprayed Ni-Al2O3 based coatings was evaluated. The coatings were deposited on a hydroturbine steel (CA6NM) by varying the content of Al2O3 in Ni. Using jet-type test rig, erosion behavior of coatings and bare steel was evaluated at different impingement angles. Detailed investigation of the surface morphology of the eroded specimens was undertaken using SEM/EDS to identify potential erosion mechanism. A parameter named "erosion mechanism identifier" (ξ) was used to predict the mode of erosion. It was observed that the coating prepared using 40 wt.% of Al2O3 showed a highest resistance to erosion. This coating enhanced the erosion resistance of the steel by 2 to 4 times. Spalling in the form of splats and chunks of material (formed by interlinking of cracks) along with fracture of Al2O3 splats were identified as primary mechanisms responsible for the loss of coating material. The erosion mechanism of coatings and bare steel predicted by ξ was in good agreement with that observed experimentally. Among different parameters,, a function of fracture toughness ( K IC) and hardness ( H) showed excellent correlation with erosion resistance of coatings at both the impingement angles.

  11. Parametric Study of Slurry-Erosion of Hydroturbine Steels with and without Detonation Gun Spray Coatings using Taguchi Technique

    Science.gov (United States)

    Grewal, Harpreet Singh; Bhandari, Sanjeev; Singh, Harpreet

    2012-09-01

    WC-Co-Cr coatings were deposited on some hydroturbine 13Cr4Ni and 16Cr5Ni steels by the detonation-gun spray process. An in-depth characterization of the as-sprayed coating was done using X-ray diffraction (XRD) and scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDS) techniques. Microhardness and porosity measurements were also made. The coating was found to have a typical splat-like morphology with some indications of unmelted carbide particles. The XRD results showed the presence of WC as the primary phase along with W2C and Co6W6C as secondary phases. Furthermore, the slurry erosion behavior of the coatings was investigated to ascertain the usefulness of the coatings to reduce the slurry erosion of the steels. The effect of four operating factors viz. the velocity, impact angle, concentration, and particle size on the slurry erosion of coated and bare steels has been studied using a high-speed jet-type test rig. The sand used as an erodent was collected from a power plant to replicate the actual turbine conditions. It has been observed that the given cermet coating can enhance the erosion resistance of the steel. Velocity was found to be the most significant factor affecting the erosion behavior of the coating, whereas it was the erodent particle size in the case of uncoated steel. As evidenced from the SEM images, the platelet mechanism of erosion seemed to be the prominent one, causing the removal of material from the surface of the steel, whereas for the coating, the formation and interlinking of cracks resulted in the removal of material.

  12. Slurry Erosion Behavior of F6NM Stainless Steel and High-Velocity Oxygen Fuel-Sprayed WC-10Co-4Cr Coating

    Science.gov (United States)

    Cui, S. Y.; Miao, Q.; Liang, W. P.; Huang, B. Z.; Ding, Z.; Chen, B. W.

    2017-02-01

    WC-10Co-4Cr coating was applied to the surface of F6NM stainless steel by high-velocity oxygen-fuel spraying. The slurry erosion behavior of the matrix and coating was examined at different rotational speeds using a self-made machine. This experiment effectively simulates real slurry erosion in an environment with high silt load. At low velocity (<6 m/s), the main failure mechanism was cavitation. Small bubbles acted as an air cushion, obstructing direct contact between sand and the matrix surface. However, at velocity above 9 m/s, abrasive wear was the dominant failure mechanism. The results indicate that WC-10Co-4Cr coating significantly improved the slurry resistance at higher velocity, because it created a thin and dense WC coating on the surface.

  13. Fracture-free surfaces of CAD/CAM lithium metasilicate glass-ceramic using micro-slurry jet erosion.

    Science.gov (United States)

    Yin, Ling; Baba, Takashi; Nakanishi, Yoshitaka

    2018-04-01

    This paper reports the use of micro-slurry jet erosion (MSJE) on CAD/CAM lithium mesilicate glass ceramic (LMGC) that is capable of achieving the fracture-free surface quality. A computer-controlled MSJE process using a low-pressure and low-concentration alumina slurry was applied to diamond-ground LMGC surfaces with surface and subsurface damage. The MSJE processed and diamond-ground LMGC surfaces were examined using scanning electron microscopy (SEM) to examine surface morphology, fractures, and residual defects. 3D confocal laser microscopy (CLM) was used to quantitatively characterize all machined surface textures as a function of processing conditions. Our results show that surface and subsurface damage induced in diamond-ground surfaces were significantly diminished after 50-cycle MSJE processing. Fracture-free surfaces were obtained after 100 MSJE cycles. Our measured parameters of the 3D surface topography included the average surface roughness, maximum peak-valley height, highest peak height, lowest valley height, and kurtosis and absolute skewness of height distributions. All these parameters were significantly reduced with the increase of MSJE cycles. This work implies that MSJE promises to be an effective manufacturing technique for the generation of fracture-free LMGC surfaces which are crucial for high-quality monolithic restorations made from the material. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Slurry Erosion Behavior of AlxCoCrFeNiTi0.5 High-Entropy Alloy Coatings Fabricated by Laser Cladding

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    Jianhua Zhao

    2018-02-01

    Full Text Available High-entropy alloys (HEAs have gained extensive attention due to their excellent properties and the related scientific value in the last decade. In this work, AlxCoCrFeNiTi0.5 HEA coatings (x: molar ratio, x = 1.0, 1.5, 2.0, and 2.5 were fabricated on Q345 steel substrate by laser-cladding process to develop a practical protection technology for fluid machines. The effect of Al content on their phase evolution, microstructure, and slurry erosion performance of the HEA coatings was studied. The AlxCoCrFeNiTi0.5 HEA coatings are composed of simple face-centered cubic (FCC, body-centered cubic (BCC and their mixture phase. Slurry erosion tests were conducted on the HEA coatings with a constant velocity of 10.08 m/s and 16–40 meshs and particles at impingement angles of 15, 30, 45, 60 and 90 degrees. The effect of three parameters, namely impingement angle, sand concentration and erosion time, on the slurry erosion behavior of AlxCoCrFeNiTi0.5 HEA coatings was investigated. Experimental results show AlCoCrFeNiTi0.5 HEA coating follows a ductile erosion mode and a mixed mode (neither ductile nor brittle for Al1.5CoCrFeNiTi0.5 HEA coating, while Al2.0CoCrFeNiTi0.5 and Al2.5CoCrFeNiTi0.5 HEA coatings mainly exhibit brittle erosion mode. AlCoCrFeNiTi0.5 HEA coating has good erosion resistance at all investigated impingement angles due to its high hardness, good plasticity, and low stacking fault energy (SFE.

  15. An Experimental Study on Slurry Erosion Resistance of Single and Multilayered Deposits of Ni-WC Produced by Laser-Based Powder Deposition Process

    Science.gov (United States)

    Balu, Prabu; Hamid, Syed; Kovacevic, Radovan

    2013-11-01

    Single and multilayered deposits containing different mass fractions of tungsten carbide (WC) in nickel (Ni)-matrix (NT-20, NT-60, NT-80) are deposited on a AISI 4140 steel substrate using a laser-based powder deposition process. The transverse cross section of the coupons reveals that the higher the mass fraction of WC in Ni-matrix leads to a more uniform distribution through Ni-matrix. The slurry erosion resistance of the fabricated coupons is tested at three different impingement angles using an abrasive water jet cutting machine, which is quantified based on the erosion rate. The top layer of a multilayered deposit (i.e., NT-60 in a two-layer NT-60 over NT-20 deposit) exhibits better erosion resistance at all three tested impingement angles when compared to a single-layer (NT-60) deposit. A definite increase in the erosion resistance is noted with an addition of nano-size WC particles. The relationship between the different mass fractions of reinforcement (WC) in the deposited composite material (Ni-WC) and their corresponding matrix (Ni) hardness on the erosion rate is studied. The eroded surface is analyzed in the light of a three-dimensional (3-D) profilometer and a scanning electron microscope (SEM). The results show that a volume fraction of approximately 62% of WC with a Ni-matrix hardness of 540 HV resulting in the gouging out of WC from the Ni-matrix by the action of slurry. It is concluded that the slurry erosion resistance of the AISI 4140 steel can be significantly enhanced by introducing single and multilayered deposits of Ni-WC composite material fabricated by the laser-based powder deposition process.

  16. Comprehensive study of the abrasive wear and slurry erosion behavior of an expanded system of high chromium cast iron and microstructural modification for enhanced wear resistance

    Science.gov (United States)

    Chung, Reinaldo Javier

    High chromium cast irons (HCCIs) have been demonstrated to be an effective material for a wide range of applications in aggressive environments, where resistances to abrasion, erosion and erosion-corrosion are required. For instance, machinery and facilities used in mining and extraction in Alberta's oil sands suffer from erosion and erosion-corrosion caused by silica-containing slurries, which create challenges for the reliability and maintenance of slurry pumping systems as well as other processing and handling equipment. Considerable efforts have been made to determine and understand the relationship between microstructural features of the HCCIs and their wear performance, in order to guide the material selection and development for specific service conditions with optimal performance. The focus was previously put on a narrow group of compositions dictated by ASTM A532. However, with recent advances in casting technology, the HCCI compositional range can be significantly expanded, which potentially brings new alloys that can be superior to those which are currently employed. This work consists of three main aspects of study. The first one is the investigation of an expanded system of white irons with their composition ranging from 1 to 6 wt.% C and 5 to 45 wt.% Cr, covering 53 alloys. This work has generated wear and corrosion maps and established correlation between the performance and microstructural features for the alloys. The work was conducted in collaboration with the Materials Development Center of Weir Minerals in Australia, and the results have been collected in a database that is used by the company to guide materials selection for slurry pump components in Alberta oil sands and in other mining operations throughout the world. The second part consists of three case studies on effects of high chromium and high carbon, respectively, on the performance of the HCCIs. The third aspect is the development of an approach to enhance the wear resistance of

  17. 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.

  18. A combined CFD-experimental method for developing an erosion equation for both gas-sand and liquid-sand flows

    Science.gov (United States)

    Mansouri, Amir

    gas-sand, water-sand and viscous liquid-sand flows with high accuracy. Furthermore, in order to gain a better understanding of the erosion mechanism, a comprehensive experimental study was conducted to investigate the important factors influencing the erosion rate in gas-sand and slurry flows. The wear pattern and total erosion ratio were measured in a direct impingement jet geometry (for both dry impact and submerged impingement jets). The effects of fluid viscosity, abrasive particle size, particle impact speed, jet inclination angle, standoff distance, sand concentration, and exposure time were investigated. Also, the eroded samples were studied with Scanning Electron Microscopy (SEM) to understand the erosion micro-structure. Also, the sand particle impact speed and angle were measured using a Particle Image Velocimetry (PIV) system. The measurements were conducted in two types of erosion testers (gas-solid and liquid-solid impinging jets). The Particle Tracking Velocimetry (PTV) technique was utilized which is capable of tracking individual small particles. Moreover, CFD modeling was performed to predict the particle impact data. Very good agreement between the CFD results and PTV measurements was observed.

  19. 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.

  20. 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.

  1. 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.

  2. 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)

  3. 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

  4. 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)

  5. Runoff erosion

    OpenAIRE

    Evelpidou, Niki (Ed.); Cordier, Stephane (Ed.); Merino, Agustin (Ed.); Figueiredo, Tomás de (Ed.); Centeri, Csaba (Ed.)

    2013-01-01

    Table of Contents PART I – THEORY OF RUNOFF EROSION CHAPTER 1 - RUNOFF EROSION – THE MECHANISMS CHAPTER 2 - LARGE SCALE APPROACHES OF RUNOFF EROSION CHAPTER 3 - MEASURING PRESENT RUNOFF EROSION CHAPTER 4 - MODELLING RUNOFF EROSION CHAPTER 5 - RUNOFF EROSION AND HUMAN SOCIETIES: THE INFLUENCE OF LAND USE AND MANAGEMENT PRACTICES ON SOIL EROSION PART II - CASE STUDIES CASE STUDIES – INTRODUCTION: RUNOFF EROSION IN MEDITERRANEAN AREA CASE STUDY 1: Soil Erosion Risk...

  6. Erosive wear of a surface coated hydroturbine steel

    Indian Academy of Sciences (India)

    Administrator

    Department of Metallurgical and Materials Engineering, Indian Institute of Technology Roorkee,. Roorkee ... turbines, pipelines and valves used in slurry transporta- tion of matter ... city gas blast erosion rig facility developed as per standard.

  7. 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

  8. 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.

  9. Erosion and erosion-corrosion

    International Nuclear Information System (INIS)

    Isomoto, Yoshinori

    2008-01-01

    It is very difficult to interpret the technical term of erosion-corrosion' which is sometimes encountered in piping systems of power plants, because of complicated mechanisms and several confusing definitions of erosion-corrosion phenomena. 'FAC (flow accelerated corrosion)' is recently introduced as wall thinning of materials in power plant systems, as a representative of 'erosion-corrosion'. FAC is, however, not necessarily well understood and compared with erosion-corrosion. This paper describes firstly the origin, definition and fundamental understandings of erosion and erosion-corrosion, in order to reconsider and reconfirm the phenomena of erosion, erosion-corrosion and FAC. Next, typical mapping of erosion, corrosion, erosion-corrosion and FAC are introduced in flow velocity and environmental corrosiveness axes. The concept of damage rate in erosion-corrosion is finally discussed, connecting dissolution rate, mass transfer of metal ions in a metal oxide film and film growth. (author)

  10. 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.

  11. 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)

  12. 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:

  13. 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

  14. 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.

  15. 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

  16. 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

  17. 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...

  18. Test installation for studying erosion-corrosion of metals for coal washing plants

    Energy Technology Data Exchange (ETDEWEB)

    Hoey, G. R.; Dingley, W.; Wiles, C. T.

    1979-02-15

    A test installation was constructed for investigating erosion-corrosion of metals by coal-water slurries. Erosion-corrosion tests of mild steel panels were conducted using slurries of alundum, quartz, washed coal and coal refuse. Wear rates were found to depend on type of abrasive, particle size and water conductivity and were reduced by cathodic protection and inhibitors. Cathodic protection of mild steel in coal slurries containing sulphate ion reduced wear by 90% and 86% for stationary and rotating panels, respectively. This study has demonstrated that the successful application of corrosion control techniques would reduce metal wastage in coal washing plants. The test installation is considered suitable for developing the techniques.

  19. Erosive gastritis

    International Nuclear Information System (INIS)

    Mohammed, S.H.; Conrad, C.; Kjoergaad, J.

    1982-01-01

    Erosive gastritis is a well-defined radiologic and endoscopic entity. It is one of the common causes of upper gastrointestinal bleeding, yet it is seldom diagnosed and often confused with a number of other diseases. This communication re-emphasizes the characteristic endoscopic and radiologic features of erosive gastritis and its differential diagnosis. Two representative cases are reported. (orig.)

  20. Erosive gastritis

    Energy Technology Data Exchange (ETDEWEB)

    Mohammed, S.H.; Conrad, C.; Kjoergaad, J.

    1982-08-01

    Erosive gastritis is a well-defined radiologic and endoscopic entity. It is one of the common causes of upper gastrointestinal bleeding, yet it is seldom diagnosed and often confused with a number of other diseases. This communication re-emphasizes the characteristic endoscopic and radiologic features of erosive gastritis and its differential diagnosis. Two representative cases are reported.

  1. An experimental study on the erosion behavior of pseudoelastic TiNi alloy in dry sand and in aggressive media

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, T.; Li, D.Y. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical Engineering

    2000-11-30

    The corrosive erosion behavior of Ti-51at.%Ni alloy under different erosion conditions was studied and compared to that of 304 stainless steel. Erosion tests were performed in a slurry-pot tester with dry sand, 3.5% NaCl slurry and 0.1 moll{sup -1} H{sub 2}SO{sub 4} slurry containing 30% silica sand, respectively. Synergistic effects of corrosion and erosion were studied in steady corrosion, polarization, dry sand erosion and micro-wear experiments. An electrochemical-scratching test characterized the failure and recovery of the passive film formed on TiNi alloy in 3.5% NaCl and 0.1 mol l{sup -1} H{sub 2}SO{sub 4} solutions, respectively. In both dry sand and the corrosive media, the TiNi alloy exhibited considerably greater erosion resistance than 304 stainless steel. (orig.)

  2. 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.

  3. 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

  4. Potential for erosion corrosion of SRS high level waste tanks

    International Nuclear Information System (INIS)

    Zapp, P.E.

    1994-01-01

    SRS high-level radioactive waste tanks will not experience erosion corrosion to any significant degree during slurry pump operations. Erosion corrosion in carbon steel structures at reported pump discharge velocities is dominated by electrochemical (corrosion) processes. Interruption of those processes, as by the addition of corrosion inhibitors, sharply reduces the rate of metal loss from erosion corrosion. The well-inhibited SRS waste tanks have a near-zero general corrosion rate, and therefore will be essentially immune to erosion corrosion. The experimental data on carbon steel erosion corrosion most relevant to SRS operations was obtained at the Hanford Site on simulated Purex waste. A metal loss rate of 2.4 mils per year was measured at a temperature of 102 C and a slurry velocity comparable to calculated SRS slurry velocities on ground specimens of the same carbon steel used in SRS waste tanks. Based on these data and the much lower expected temperatures, the metal loss rate of SRS tanks under waste removal and processing conditions should be insignificant, i.e. less than 1 mil per year

  5. Protocol for Measuring the Thermal Properties of a Supercooled Synthetic Sand-water-gas-methane Hydrate Sample.

    Science.gov (United States)

    Muraoka, Michihiro; Susuki, Naoko; Yamaguchi, Hiroko; Tsuji, Tomoya; Yamamoto, Yoshitaka

    2016-03-21

    Methane hydrates (MHs) are present in large amounts in the ocean floor and permafrost regions. Methane and hydrogen hydrates are being studied as future energy resources and energy storage media. To develop a method for gas production from natural MH-bearing sediments and hydrate-based technologies, it is imperative to understand the thermal properties of gas hydrates. The thermal properties' measurements of samples comprising sand, water, methane, and MH are difficult because the melting heat of MH may affect the measurements. To solve this problem, we performed thermal properties' measurements at supercooled conditions during MH formation. The measurement protocol, calculation method of the saturation change, and tips for thermal constants' analysis of the sample using transient plane source techniques are described here. The effect of the formation heat of MH on measurement is very small because the gas hydrate formation rate is very slow. This measurement method can be applied to the thermal properties of the gas hydrate-water-guest gas system, which contains hydrogen, CO2, and ozone hydrates, because the characteristic low formation rate of gas hydrate is not unique to MH. The key point of this method is the low rate of phase transition of the target material. Hence, this method may be applied to other materials having low phase-transition rates.

  6. River modeling and multi-level fish health assessment to evaluate impacts from oil sands water releases (Part 2)

    International Nuclear Information System (INIS)

    Shaw, R.; Swanson, S.M.; Lagimodiere, M.; Gulley, J.

    1995-01-01

    A multi-level, multi-scale approach was used to assess potential impacts to fish health from oil sands water releases. The method used to arrive at predicted impacts involved assembling experimental data on the effects of chronic exposure to oil sands wastewaters on biochemical, physiological and whole-organism endpoint. This information was used to determine no effect levels (NOELs) and lowest effect levels (LOELs) for the suite of fish health parameters used in laboratory experiments (primarily biochemical and physiological measurement endpoints). LOELs and NOELs were compared to modeled concentrations of wastewater in the Athabasca River for five time snapshots. For each time period, concentrations were predicted based on mean annual flows and 7Q10 flows (low flows). This comparison was used to predict impacts on biochemical/physiological endpoints. Impacts on at the whole-organism and population-level were determined by comparing what the laboratory data would predict with what was observed in the field. This process was used to draw a conclusion regarding the health and sustainability of fish populations

  7. 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.

  8. 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.

  9. 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.

  10. Erhversbetinget erosion?

    DEFF Research Database (Denmark)

    Dige, Irene; Gjørup, Hans; Nyvad, Bente

    2012-01-01

    Baggrund – I forbindelse med dental erosion er en grundig udredning af patienten vigtig, således at årsagen til erosionernes opståen findes, og der kan iværksættes adækvat forebyggende indsats. En sådan udredning er ikke mindst vigtig, når arbejdsmiljøet mistænkes. Patienttilfælde – En 30-årig...... arbejdsskade, men ikke anerkendt, da erosioner ikke er optaget på Arbejdsskadestyrelsens liste over erhvervssygdomme. En systematisk registrering af lignende tilfælde kunne imidlertid på sigt ændre retspraksis for fremtidige patienter med arbejdsbetinget erosion....... patient, der arbejder som pladesmed, blev henvist til Landsdels- og Videnscenter, Århus Sygehus, med henblik på udredning af patientens kraftige slid. Patienten udviste ikke-alderssvarende tandslid af emalje og dentin svarende til erosion forårsaget af syredampe i arbejdsmiljøet, muligvis forstærket af...

  11. Yield Stress Reduction of DWPF Melter Feed Slurries

    International Nuclear Information System (INIS)

    Stone, M.E.; Smith, M.E.

    2007-01-01

    indicates that the bead slurry would not require higher flows rates than frit slurry at DWPF during transfers. Another key finding was that the pump impeller was not significantly damaged by the bead slurry, while the Frit 320 slurry rapidly destroyed the impeller. Evidence of this was first observed when black particles were seen in the Frit 320 slurry being recirculated and then confirmed by a post-test inspection of the impeller. Finally, the pumping of bead slurry could be recovered even if flow is stopped. The Frit 320 slurry could not be restarted after stopping flow due to the nature of the frit to pack tightly when settled. Beads were shown to represent a significant process improvement versus frit for the DWPF process in lowering yield stress of the melter feed. Lower erosion of process equipment is another expected benefit

  12. 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)

  13. 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.

  14. 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.

  15. 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....

  16. 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)

  17. 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.

  18. 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.

  19. 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.

  20. Laser processing of cast iron for enhanced erosion resistance

    International Nuclear Information System (INIS)

    Chen, C.H.; Altstetter, C.J.; Rigsbee, J.M.

    1984-01-01

    The surfaces of nodular and gray cast iron have been modified by CO 2 laser processing for enhanced hardness and erosion resistance. Control of the near-surface microstructure was achieved primarily by controlling resolidification of the laser melted layer through variations in laser beam/target interaction time and beam power density. Typical interaction times and power densities used were 5 msec and 500 kW/cm 2 . Two basic kinds of microstructure can be produced-a feathery microstructure with high hardness (up to 1245 HV) and a dendritic microstructure with a metastable, fully austenitic matrix and lower hardness (600 to 800 HV). Erosion testing was done using slurries of SiO 2 or SiC in water. Weight loss and crater profile measurements were used to evaluate the erosion characteristics of the various microstructures. Both ductile and gray cast iron showed marked improvement in erosion resistance after laser processing

  1. 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.

  2. 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).

  3. 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).

  4. 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.

  5. 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.

  6. 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

  7. The effectiveness of aerial hydromulch as an erosion control treatment in burned chaparral watersheds

    Science.gov (United States)

    Pete Wohlgemuth; Jan Beyers; Pete Robichaud

    2011-01-01

    High severity wildfire can make watersheds susceptible to accelerated erosion, which impedes resource recovery and threatens life, property, and infrastructure in downstream human communities. Land managers often use mitigation measures on the burned hillside slopes to reduce postfire sediment fluxes. Hydromulch, a slurry of paper or wood fiber that dries to a...

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  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. Rainfall Erosivity in Europe

    DEFF Research Database (Denmark)

    Panagos, Panos; Ballabio, Cristiano; Borrelli, Pasquale

    2015-01-01

    Rainfall is one the main drivers of soil erosion. The erosive force of rainfall is expressed as rainfall erosivity. Rainfall erosivity considers the rainfall amount and intensity, and is most commonly expressed as the Rfactor in the USLE model and its revised version, RUSLE. At national...... and continental levels, the scarce availability of data obliges soil erosion modellers to estimate this factor based on rainfall data with only low temporal resolution (daily, monthly, annual averages). The purpose of this study is to assess rainfall erosivity in Europe in the form of the RUSLE R-factor, based...

  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. 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

  1. Mapping erosion from space

    NARCIS (Netherlands)

    Vrieling, A.

    2007-01-01

    Soil erosion by water is the most important land degradation problem worldwide. Spatial information on erosion is required for defining effective soil and water conservation strategies. Satellite remote sensing can provide relevant input to regional erosion assessment. This thesis comprises a review

  2. Erosion-corrosion

    International Nuclear Information System (INIS)

    Aghili, B.

    1999-05-01

    A literature study on erosion-corrosion of pipings in the nuclear industry was performed. Occurred incidents are reviewed, and the mechanism driving the erosion-corrosion is described. Factors that influence the effect in negative or positive direction are treated, as well as programs for control and inspection. Finally, examples of failures from databases on erosion-corrosion are given in an attachment

  3. Assessing storm erosion hazards

    NARCIS (Netherlands)

    Ranasinghe, Ranasinghe W M R J B; Callaghan, D.; Ciavola, Paolo; Coco, Giovanni

    2017-01-01

    The storm erosion hazard on coasts is usually expressed as an erosion volume and/or associated episodic coastline retreat. The accurate assessment of present-day and future storm erosion volumes is a key task for coastal zone managers, planners and engineers. There are four main approaches that can

  4. Impact of Spherical Frit Beads on Simulated DWPF Slurries

    International Nuclear Information System (INIS)

    SMITH, MICHAEL

    2005-01-01

    -scale Slurry-Fed Melt Rate Furnace (SMRF) showed that melt rate was increased with feeds with either higher weight percent solids or lower acid stoichiometry. Past SRNL pilot scale melter tests have also shown the same increase in melt rate with higher weight percent solids. Although the use of beads may increase melt rate and also aid in the operation of the SME, MFT, and melter feed loop, there are several issues that must be addressed before going into a more in depth study of the use of beads at DWPF. The following issues were investigated and are documented in this report: (1) The impact of glass former shape on settling behavior; (2) Impact of glass former shape on the rheology of the feed product; (3) Impact of glass former shape on erosion of equipment containing glass formers; (4) Impact of glass former shape on slurry addition to the SME; and (5) Impact of glass former shape on melt rate

  5. 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

  6. Managing dental erosion.

    Science.gov (United States)

    Curtis, Donald A; Jayanetti, Jay; Chu, Raymond; Staninec, Michal

    2012-01-01

    The clinical signs of dental erosion are initially subtle, yet often progress because the patient remains asymptomatic, unaware and uninformed. Erosion typically works synergistically with abrasion and attrition to cause loss of tooth structure, making diagnosis and management complex. The purpose of this article is to outline clinical examples of patients with dental erosion that highlight the strategy of early identification, patient education and conservative restorative management. Dental erosion is defined as the pathologic chronic loss of dental hard tissues as a result of the chemical influence of exogenous or endogenous acids without bacterial involvement. Like caries or periodontal disease, erosion has a multifactorial etiology and requires a thorough history and examination for diagnosis. It also requires patient understanding and compliance for improved outcomes. Erosion can affect the loss of tooth structure in isolation of other cofactors, but most often works in synergy with abrasion and attrition in the loss of tooth structure (Table 1). Although erosion is thought to be an underlying etiology of dentin sensitivity, erosion and loss of tooth structure often occurs with few symptoms. The purpose of this article is threefold: first, to outline existing barriers that may limit early management of dental erosion. Second, to review the clinical assessment required to establish a diagnosis of erosion. And third, to outline clinical examples that review options to restore lost tooth structure. The authors have included illustrations they hope will be used to improve patient understanding and motivation in the early management of dental erosion.

  7. 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...

  8. 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

  9. 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.

  10. 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)

  11. 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)

  12. 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.

  13. 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)

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. Protection from erosion following wildfire

    Science.gov (United States)

    Peter R. Robichaud; William J. Elliot

    2006-01-01

    Erosion in the first year after a wildfire can be up to three orders of magnitude greater than the erosion from undisturbed forests. To mitigate potential postfire erosion, various erosion control treatments are applied on highly erodible areas with downstream resources in need of protection. Because postfire erosion rates generally decline by an order of magnitude for...

  1. 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

  2. Saliva and dental erosion

    Directory of Open Access Journals (Sweden)

    Marília Afonso Rabelo Buzalaf

    2012-10-01

    Full Text Available Dental erosion is a multifactorial condition. The consideration of chemical, biological and behavioral factors is fundamental for its prevention and therapy. Among the biological factors, saliva is one of the most important parameters in the protection against erosive wear. Objective: This review discusses the role of salivary factors on the development of dental erosion. Material and Methods: A search was undertaken on MeDLINe website for papers from 1969 to 2010. The keywords used in the research were "saliva", "acquired pellicle", "salivary flow", "salivary buffering capacity" and "dental erosion". Inclusion of studies, data extraction and quality assessment were undertaken independently and in duplicate by two members of the review team. Disagreements were solved by discussion and consensus or by a third party. Results: Several characteristics and properties of saliva play an important role in dental erosion. Salivary clearance gradually eliminates the acids through swallowing and saliva presents buffering capacity causing neutralization and buffering of dietary acids. Salivary flow allows dilution of the acids. In addition, saliva is supersaturated with respect to tooth mineral, providing calcium, phosphate and fluoride necessary for remineralization after an erosive challenge. Furthermore, many proteins present in saliva and acquired pellicle play an important role in dental erosion. Conclusions: Saliva is the most important biological factor affecting the progression of dental erosion. Knowledge of its components and properties involved in this protective role can drive the development of preventive measures targeting to enhance its known beneficial effects.

  3. Scales and erosion

    Science.gov (United States)

    There is a need to develop scale explicit understanding of erosion to overcome existing conceptual and methodological flaws in our modelling methods currently applied to understand the process of erosion, transport and deposition at the catchment scale. These models need to be based on a sound under...

  4. Saliva and dental erosion.

    Science.gov (United States)

    Buzalaf, Marília Afonso Rabelo; Hannas, Angélicas Reis; Kato, Melissa Thiemi

    2012-01-01

    Dental erosion is a multifactorial condition. The consideration of chemical, biological and behavioral factors is fundamental for its prevention and therapy. Among the biological factors, saliva is one of the most important parameters in the protection against erosive wear. This review discusses the role of salivary factors on the development of dental erosion. A search was undertaken on MeDLINe website for papers from 1969 to 2010. The keywords used in the research were "saliva", "acquired pellicle", "salivary flow", "salivary buffering capacity" and "dental erosion". Inclusion of studies, data extraction and quality assessment were undertaken independently and in duplicate by two members of the review team. Disagreements were solved by discussion and consensus or by a third party. Several characteristics and properties of saliva play an important role in dental erosion. Salivary clearance gradually eliminates the acids through swallowing and saliva presents buffering capacity causing neutralization and buffering of dietary acids. Salivary flow allows dilution of the acids. In addition, saliva is supersaturated with respect to tooth mineral, providing calcium, phosphate and fluoride necessary for remineralization after an erosive challenge. Furthermore, many proteins present in saliva and acquired pellicle play an important role in dental erosion. Saliva is the most important biological factor affecting the progression of dental erosion. Knowledge of its components and properties involved in this protective role can drive the development of preventive measures targeting to enhance its known beneficial effects.

  5. 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.

  6. 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

  7. 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

  8. 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

  9. 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...

  10. 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

  11. 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)

  12. WTP Pretreatment Facility Potential Design Deficiencies--Sliding Bed and Sliding Bed Erosion Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, E. K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-05-06

    This assessment is based on readily available literature and discusses both Newtonian and non-Newtonian slurries with respect to sliding beds and erosion due to sliding beds. This report does not quantify the size of the sliding beds or erosion rates due to sliding beds, but only assesses if they could be present. This assessment addresses process pipelines in the Pretreatment (PT) facility and the high level waste (HLW) transfer lines leaving the PT facility to the HLW vitrification facility concentrate receipt vessel.

  13. WTP Pretreatment Facility Potential Design Deficiencies--Sliding Bed and Sliding Bed Erosion Assessment

    International Nuclear Information System (INIS)

    Hansen, E. K.

    2015-01-01

    This assessment is based on readily available literature and discusses both Newtonian and non-Newtonian slurries with respect to sliding beds and erosion due to sliding beds. This report does not quantify the size of the sliding beds or erosion rates due to sliding beds, but only assesses if they could be present. This assessment addresses process pipelines in the Pretreatment (PT) facility and the high level waste (HLW) transfer lines leaving the PT facility to the HLW vitrification facility concentrate receipt vessel.

  14. On the study of ricochet and penetration in sand, water and gelatin by spheres, 7.62 mm APM2, and 25 mm projectiles

    Directory of Open Access Journals (Sweden)

    John F. Moxnes

    2016-04-01

    Full Text Available We examine the ricochet and penetration behavior in sand, water and gelatin by steel spheres, 7.62 mm APM2 and 25 mm projectiles. A threshold impact angle (critical angle exists beyond which ricochet cannot occur. The Autodyn simulation code with the smooth particle hydrodynamic (SPH method and Impetus Afea Solver with the corpuscular model are used and the results are compared with experimental and analytical results. The resistance force in sand for spheres was proportional to a term quadratic in velocity plus a term linear in velocity. The drag coefficient for the quadratic term was 0.65. The Autodyn and Impetus Afea codes simulate too large penetration due to the lack of a linear velocity resistance force. Critical ricochet angles were consistent with analytical results in the literature. In ballistic gelatin at velocities of 50–850 m/s a drag coefficient of 0.30 fits the high speed camera recordings if a linear velocity resistance term is included. However, only a quadratic velocity resistance force with drag coefficient that varies with the Reynolds number also fits the measurements. The simulation of a sphere in water with Autodyn showed too large drag coefficient. The 7.62 mm APM2 core simulations in sand fit reasonable well for both codes. The 25 mm projectile ricochet simulations in sand show consistency with the high speed camera recordings. Computer time was reduced by one to two orders of magnitudes when applying the Impetus Afea Solver compared to Autodyn code due to the use of the graphics processing units (GPU.

  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. 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.

  17. Measurement of erosion: Is it possible?

    NARCIS (Netherlands)

    Stroosnijder, L.

    2005-01-01

    Reasons for erosion measurements are: (1) to determine the environmental impact of erosion and conservation practices, (2) scientific erosion research; (3) development and evaluation of erosion control technology; (4) development of erosion prediction technology and (5) allocation of conservation

  18. Numerical modelling of concentrated leak erosion during Hole Erosion Tests

    OpenAIRE

    Mercier, F.; Bonelli, S.; Golay, F.; Anselmet, F.; Philippe, P.; Borghi, R.

    2015-01-01

    This study focuses on the numerical modelling of concentrated leak erosion of a cohesive soil by a turbulent flow in axisymmetrical geometry, with application to the Hole Erosion Test (HET). The numerical model is based on adaptive remeshing of the water/soil interface to ensure accurate description of the mechanical phenomena occurring near the soil/water interface. The erosion law governing the interface motion is based on two erosion parameters: the critical shear stress and the erosion co...

  19. 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.)

  20. 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

  1. 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.

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. Rainfall erosivity in Europe.

    Science.gov (United States)

    Panagos, Panos; Ballabio, Cristiano; Borrelli, Pasquale; Meusburger, Katrin; Klik, Andreas; Rousseva, Svetla; Tadić, Melita Perčec; Michaelides, Silas; Hrabalíková, Michaela; Olsen, Preben; Aalto, Juha; Lakatos, Mónika; Rymszewicz, Anna; Dumitrescu, Alexandru; Beguería, Santiago; Alewell, Christine

    2015-04-01

    Rainfall is one the main drivers of soil erosion. The erosive force of rainfall is expressed as rainfall erosivity. Rainfall erosivity considers the rainfall amount and intensity, and is most commonly expressed as the R-factor in the USLE model and its revised version, RUSLE. At national and continental levels, the scarce availability of data obliges soil erosion modellers to estimate this factor based on rainfall data with only low temporal resolution (daily, monthly, annual averages). The purpose of this study is to assess rainfall erosivity in Europe in the form of the RUSLE R-factor, based on the best available datasets. Data have been collected from 1541 precipitation stations in all European Union (EU) Member States and Switzerland, with temporal resolutions of 5 to 60 min. The R-factor values calculated from precipitation data of different temporal resolutions were normalised to R-factor values with temporal resolutions of 30 min using linear regression functions. Precipitation time series ranged from a minimum of 5 years to a maximum of 40 years. The average time series per precipitation station is around 17.1 years, the most datasets including the first decade of the 21st century. Gaussian Process Regression (GPR) has been used to interpolate the R-factor station values to a European rainfall erosivity map at 1 km resolution. The covariates used for the R-factor interpolation were climatic data (total precipitation, seasonal precipitation, precipitation of driest/wettest months, average temperature), elevation and latitude/longitude. The mean R-factor for the EU plus Switzerland is 722 MJ mm ha(-1) h(-1) yr(-1), with the highest values (>1000 MJ mm ha(-1) h(-1) yr(-1)) in the Mediterranean and alpine regions and the lowest (<500 MJ mm ha(-1) h(-1) yr(-1)) in the Nordic countries. The erosivity density (erosivity normalised to annual precipitation amounts) was also the highest in Mediterranean regions which implies high risk for erosive events and floods

  7. 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

  8. 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)

  9. 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...

  10. 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

  11. 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

  12. 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...

  13. Coastal Erosion Control Methods

    Science.gov (United States)

    Greene, V.

    2016-12-01

    Coastal erosion is bad because the ecosystem there will be washed away and the animals could drown or be displaced and have to adapt to a new ecosystem that they are not prepared for. I'm interested in this problem because if there aren't beaches when I grow up I won't be able to do the things I would really like to do. I would like to be a marine biologist. Secondly, I don't want to see beach houses washed away. I would like to see people live in harmony with their environment. So, to study ways in which to preserve beaches I will make and use models that test different erosion controls. Two different ideas for erosion control I tested are using seaweed or a rock berm. I think the rock berm will work better than the model of seaweed because the seaweed is under water and the waves can carry the sand over the seaweed, and the rock berm will work better because the rocks will help break the waves up before they reach the shore and the waves can not carry the sand over the rocks that are above the water. To investigate this I got a container to use to model the Gulf of Mexico coastline. I performed several test runs using sand and water in the container to mimic the beach and waves from the Gulf of Mexico hitting the shoreline. I did three trials for the control (no erosion control), seaweed and a rock berm. Rock berms are a border of a raised area of rock. The model for seaweed that I used was plastic shopping bags cut into strips and glued to the bottom of my container to mimic seaweed. My results were that the control had the most erosion which ranged from 2.75 - 3 inches over 3 trials. The seaweed was a little better than the control but was very variable and ranged from 1.5 - 3 inches over 3 trials. The rock berm worked the best out of all at controlling erosion with erosion ranging from 1.5 - 2 inches. My hypothesis was correct because the rock berm did best to control erosion compared to the control which had no erosion control and the model with seaweed.

  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. 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

  19. 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.

  20. 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)

  1. 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...

  2. 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

  3. 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.

  4. 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

  5. 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.

  6. Erosive Lichen Planus.

    Science.gov (United States)

    Mauskar, Melissa

    2017-09-01

    Lichen planus is an inflammatory mucocutaneous condition with a myriad of clinical manifestations. There are 3 forms of lichen planus that effect the vulva: papulosquamous, hypertrophic, and erosive. Erosive lichen planus can progress to vulvar scaring, vaginal stenosis, and squamous cell carcinoma; these long-term sequelae cause sexual distress, depression, and decreased quality of life for patients. Diagnosis is often delayed because of patient embarrassment or clinician misdiagnosis. Early recognition and treatment is essential to decreasing the morbidity of this condition. Multimodal treatment, along with a multidisciplinary approach, will improve outcomes and further clinical advances in studying this condition. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Effects of cattle manure on erosion rates and runoff water pollution by faecal coliforms.

    Science.gov (United States)

    Ramos, M C; Quinton, J N; Tyrrel, S F

    2006-01-01

    The large quantities of slurry and manure that are produced annually in many areas in which cattle are raised could be an important source of organic matter and nutrients for agriculture. However, the benefits of waste recycling may be partially offset by the risk of water pollution associated with runoff from the fields to which slurry or manure has been applied. In this paper, the effects of cattle manure application on soil erosion rates and runoff and on surface water pollution by faecal coliforms are analysed. Rainfall simulations at a rate of 70 mm h(-1) were conducted in a sandy loam soil packed into soil flumes (2.5m long x 1m wide) at a bulk density of 1400 kg m(-3), with and without cattle slurry manure applied on the surface. For each simulation, sediment and runoff rates were analysed and in those simulations with applied slurry, presumptive faecal coliform (PFC) concentrations in the runoff were evaluated. The application of slurry on the soil surface appeared to have a protective effect on the soils, reducing soil detachment by up to 70% but increasing runoff volume by up to 30%. This practice implies an important source of pollution for surface waters especially if rainfall takes place within a short period after application. The concentrations of micro-organisms (presumptive faecal coliforms (PFCs)) found in water runoff ranged from 1.9 x 10(4) to 1.1 x 10(6) PFC 100mL(-1), depending on the initial concentration in the slurry, and they were particularly high during the first phases of the rainfall event. The result indicates a strong relationship between the faecal coliforms transported by runoff and the organic matter in the sediment.

  8. Study of corrosive-erosive wear behaviour of Al6061/albite composites

    International Nuclear Information System (INIS)

    Sharma, S.C.; Krishna, M.; Murthy, H.N. Narasimha; Tarachandra, R.; Satyamoorthy, M.; Bhattacharyya, D.

    2006-01-01

    This investigation analyses the influence of dispersed alumina particles on the wear behaviour of the Al/albite composites in a corrosive environment. The composites were prepared by modified pressure die-casting technique. The corrosive-erosive wear experiments were carried out on a proprietary corrosion-erosion wear tester to study the wear characteristics of the composites. The slurry was made up of water and alumina (size: 90-150 μm, proportion: 0-30 wt.%), while H 2 SO 4 (0.01, 0.1 and 1N) was added to create the corrosive conditions. Experiments were arranged to test the relationships among the corrosive-erosive wear rate, concentrations of H 2 SO 4 and alumina in the slurry, weight percent of albite in the composite, erosion speed and distance. Wear rate varies marginally at low speeds but sharply increases at higher speeds. The corrosive wear rate logarithmically increased with the increasing concentration of the corrosive medium. The effect of abrasive particles and corrosion medium on the wear behaviour of the composite is explained experimentally, theoretically and using scanning electron microscopy

  9. Simulating cold production by a coupled reservoir-geomechanics model with sand erosion

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y.; Xue, S. [Petro-Geotech Inc., Calgary, AB (Canada)

    2002-06-01

    This paper presents a newly developed fully coupled reservoir-geomechanics model with sand erosion. Sand production occurs during aggressive production induced by the impact of viscous fluid flow and the in situ stress concentration near a wellbore, as well as by perforation tips in poorly consolidated formations. This compromises oil production, increases well completion costs, and reduces the life cycles of equipment down hole and on the surface. The proposed model can be used for sand production studies in conventional oil/gas reservoirs such as the North Sea as well as in heavy oil reservoirs such as in northwestern Canada. Instead of generating a high permeability network in reservoirs, the enhanced oil production is determined by the increase in the effective wellbore radius. This paper presents the general model. A detailed study on the capillary pressure and the impact of multiphase flow on sanding and erosion will be conducted at a later date. It appears that 2 phase flow can be important to elastoplasticity if no significant sand erosion has occurred. It was determined that high porosity is induced by erosion and capillary pressure. Two phase flow can be important when the built-up drag force carries sand-fluid slurry into the well. It is concluded that viscosity and flow velocity can help estimate the slurry transport, sand rate and enhanced oil production. 22 refs., 3 tabs., 11 figs.

  10. Mesh erosion after abdominal sacrocolpopexy.

    Science.gov (United States)

    Kohli, N; Walsh, P M; Roat, T W; Karram, M M

    1998-12-01

    To report our experience with erosion of permanent suture or mesh material after abdominal sacrocolpopexy. A retrospective chart review was performed to identify patients who underwent sacrocolpopexy by the same surgeon over 8 years. Demographic data, operative notes, hospital records, and office charts were reviewed after sacrocolpopexy. Patients with erosion of either suture or mesh were treated initially with conservative therapy followed by surgical intervention as required. Fifty-seven patients underwent sacrocolpopexy using synthetic mesh during the study period. The mean (range) postoperative follow-up was 19.9 (1.3-50) months. Seven patients (12%) had erosions after abdominal sacrocolpopexy with two suture erosions and five mesh erosions. Patients with suture erosion were asymptomatic compared with patients with mesh erosion, who presented with vaginal bleeding or discharge. The mean (+/-standard deviation) time to erosion was 14.0+/-7.7 (range 4-24) months. Both patients with suture erosion were treated conservatively with estrogen cream. All five patients with mesh erosion required transvaginal removal of the mesh. Mesh erosion can follow abdominal sacrocolpopexy over a long time, and usually presents as vaginal bleeding or discharge. Although patients with suture erosion can be managed successfully with conservative treatment, patients with mesh erosion require surgical intervention. Transvaginal removal of the mesh with vaginal advancement appears to be an effective treatment in patients failing conservative management.

  11. 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

  12. Erosion of dust aggregates

    NARCIS (Netherlands)

    Seizinger, A.; Krijt, S.; Kley, W.

    2013-01-01

    Aims: The aim of this work is to gain a deeper insight into how much different aggregate types are affected by erosion. Especially, it is important to study the influence of the velocity of the impacting projectiles. We also want to provide models for dust growth in protoplanetary disks with simple

  13. Hydrology and soil erosion

    Science.gov (United States)

    Leonard J. Lane; Mary R. Kidwell

    2003-01-01

    We review research on surface water hydrology and soil erosion at the Santa Rita Experimental Range (SRER). Almost all of the research was associated with eight small experimental watersheds established from 1974 to 1975 and operated until the present. Analysis of climatic features of the SRER supports extending research findings from the SRER to broad areas of the...

  14. Bentonite erosion. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Birgersson, Martin; Boergesson, Lennart; Hedstroem, Magnus; Karnland, Ola; Nilsson, Ulf (Clay Technology AB, Lund (Sweden))

    2009-12-15

    Low saline water may reach KBS-3 repository depth, e.g. during periods of glaciation. Under such aqueous conditions, the montmorillonite part of the bentonite buffer might transform into a sol and thereby be transported away with flowing water in fractures. The primary aim with this report is to improve the understanding of the basic principles for this possible montmorillonite particle release. The report includes experimental and theoretical work performed at Clay Technology. Natural bentonite and ion-exchanged purified montmorillonite from three different geographical origins, Wyoming (U.S.), Milos (Greece) and Kutch (India) have been studied. Experimental and/or theoretical investigations have been performed with respect to: - Free swelling ability; - Rheological properties; - Rate of bentonite loss into fractures; - Filtering; - Ion exchange; - Sol formation ability; - Ion diffusion; - Mass loss due to erosion. The performed erosion experiments show that erosion does not occur in a mixed calcium/sodium montmorillonite with at least 20% calcium in exchange positions, when the external solution contains above 4 mM charge equivalents. This result is in agreement with the presented conceptual view of sol formation and measured equilibrium properties in mixed calcium/sodium montmorillonite. The findings imply that the buffer will be stable for non-glacial conditions. However, erosion due to sol formation cannot be ruled out for glacial conditions.

  15. Erosion scenarios for Wellenberg

    International Nuclear Information System (INIS)

    Klemenz, W.

    1993-09-01

    The proposed Wellenberg site for a radioactive waste repository is located between Altzellen in the Engelberger valley and the Oberrickenbach valley, in a thick Valanginian marl series. The marl is generally overlaid with unconsolidated rocks but reaches to the surface in some places. In contrast to the situation in the Oberbauenstock region this marl complex is not protected by an overlying erosion resistant series and exhibits a marked relief. The question therefore arises with respect to the Wellenberg site, to what extent will the marl (i.e. the repository host rock formation) be removed by erosion processes during the 100,000 years interval under consideration and what overburden will remain at the end of this period. This report presents the results of an investigation of the longterm behaviour of the proposed site in respect of those processes of erosion and deposition which can lead to changes in the terrain surface and its location relative to the repository. A wide range of possible scenarios encompassing different developments of climatic conditions during the 100,000 year period of interest, was investigated. In addition to the continuation of the present climate and the occurrence of a new ice age on the scale of the Wuerm glaciation the consequences of altered climatic conditions on erosion removal of the repository overburden were considered. Within the 100,000 year period of interest none of the scenarios considered leads to the exposure of the repository. (author) figs., tabs, refs

  16. Dune erosion above revetments

    NARCIS (Netherlands)

    Van Thiel de Vries, J.S.M.

    2012-01-01

    In a situation with a narrow dune, the dune base can be protected with a revetment to reduce dune erosion during extreme events. To quantify the effects of a revetment on storm impact, the functionality of the numerical storm impact model XBeach (Roelvink et al., 2009) is extended to account for the

  17. Bentonite erosion. Final report

    International Nuclear Information System (INIS)

    Birgersson, Martin; Boergesson, Lennart; Hedstroem, Magnus; Karnland, Ola; Nilsson, Ulf

    2009-12-01

    Low saline water may reach KBS-3 repository depth, e.g. during periods of glaciation. Under such aqueous conditions, the montmorillonite part of the bentonite buffer might transform into a sol and thereby be transported away with flowing water in fractures. The primary aim with this report is to improve the understanding of the basic principles for this possible montmorillonite particle release. The report includes experimental and theoretical work performed at Clay Technology. Natural bentonite and ion-exchanged purified montmorillonite from three different geographical origins, Wyoming (U.S.), Milos (Greece) and Kutch (India) have been studied. Experimental and/or theoretical investigations have been performed with respect to: - Free swelling ability; - Rheological properties; - Rate of bentonite loss into fractures; - Filtering; - Ion exchange; - Sol formation ability; - Ion diffusion; - Mass loss due to erosion. The performed erosion experiments show that erosion does not occur in a mixed calcium/sodium montmorillonite with at least 20% calcium in exchange positions, when the external solution contains above 4 mM charge equivalents. This result is in agreement with the presented conceptual view of sol formation and measured equilibrium properties in mixed calcium/sodium montmorillonite. The findings imply that the buffer will be stable for non-glacial conditions. However, erosion due to sol formation cannot be ruled out for glacial conditions.

  18. Categorization of erosion control matting.

    Science.gov (United States)

    2012-05-29

    Erosion control is a critical aspect of any Georgia Department of Transportation (GDOT) : construction project, with the extreme negative impacts of high sediment loads in natural : waterways having been well documented. A variety of erosion control ...

  19. Measurement and analysis of polarization curves of mild steel in sodium carbonate/bicarbonate solution under erosion-corrosion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Q. [Taiyuan University of Technology, Taiyuan (China). Research Institute of Surface Engineering

    2002-06-01

    The polarization curves of mild steel in de-aerated 0.5 and mol NaHCO{sub 3} + 0.5 mol Na{sub 2}CO{sub 3} solution with and without erodent particles of 300 g/L of 100 {mu}m alumina have been measured using a rotating cylinder electrode (RCE) apparatus over the range of rotation speeds fro 0 to 4,000 r/min. The results show that the mild steel in the de-aerated slurry exhibits classical active/passive polarization behavior. The speed of cylinder rotation has a great effect in the presence of particles on the active dissolution current density. The erosion-corrosion process is severely erosion-dominated for the mild steel. However, the poor corrosion resistance of the mild steel in such turbulent slurries is also significant, especially at lower than 4 m/s. 19 refs., 5 figs.

  20. MoO3/Al2O3 catalyst: Comparison of catalysts prepared by new slurry impregnation with molybdic acid with conventional samples

    International Nuclear Information System (INIS)

    Spojakina, A.; Kostova, N.; Vit, Z.; Zdrazil, M.

    2003-01-01

    Alumina-supported molybdena catalysts were prepared by conventional impregnation with (NH 4 ) 6 Mo 7 O 24 (CIM) and by a new slurry impregnation method (SIM). SIM is the reaction of alumina support with a slurry of MoO 3 in water. Two commercial supports were used and the commercial Mo 3 /Al 2 O 3 catalyst was included for comparison. Maximum amount of MoO 3 deposited by SIM was about 19-20 % MoO 3 with the surface area of the support of 260-280 m 2 g -1 and this corresponded to saturation monolayer of similar density as described in literature for CIM catalysts. At the ratios of MoO 3 to Al 2 O 3 in the impregnation slurry below saturation monolayer, the pH of the slurry was 3.5-6 (depending on loading) and chemical erosion of alumina is negligible. However, using the large excess of MoO 3 (35% MoO 3 ) the pH was 2.4-3.4 and chemical erosion of alumina occurred. Silica contained in alumina supports was partly extracted as soluble silicomolybdic anions during SIM. The catalysts were characterized by BET, IR, DRS (UV-vis and NIR), TPR and catalytic activity in hydrodesulfurization of thiophene. Calcination had no significant effect on the properties of SIM catalysts and this proved that calcination is not needed in that method. All catalysts exhibited features of high monolayer dispersion of molybdena and no significant difference in structure and catalytic properties was observed between SIM and CIM catalysts. This confirmed that SIM is a simple, clean and reliable method of preparation of monolayer type MoO 3 /Al 2 O 3 catalysts. (author)

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Rainfall erosivity map for Ghana

    International Nuclear Information System (INIS)

    Oduro Afriyie, K.

    1995-10-01

    Monthly rainfall data, spanning over a period of more than thirty years, were used to compute rainfall erosivity indices for various stations in Ghana, using the Fournier index, c, defined as p 2 /P, where p is the rainfall amount in the wettest month and P is the annual rainfall amount. Values of the rainfall erosivity indices ranged from 24.5 mm at Sunyani in the mid-portion of Ghana to 180.9 mm at Axim in the south western coastal portion. The indices were used to construct a rainfall erosivity map for the country. The map revealed that Ghana may be broadly divided into five major erosion risk zones. The middle sector of Ghana is generally in the low erosion risk zone; the northern sector is in the moderate to severe erosion risk zone, while the coastal sector is in the severe to extreme severe erosion risk zone. (author). 11 refs, 1 fig., 1 tab

  6. 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.

  7. 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.

  8. 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

  9. 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.)

  10. 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.

  11. 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.

  12. Performance of HVOF carbide coatings under erosion/corrosion

    International Nuclear Information System (INIS)

    Simard, S.; Arsenault, B.; Legoux, J.G.; Hawthorne, H.M.

    1999-01-01

    Cermet based materials are known to have an excellent performance under several wear conditions. High velocity oxy-fuel (HVOF) technology allows the deposition of such hard materials in the form of protective coatings onto different surfaces. Under slurry erosion, the performance of the coatings is influenced by the occurrence of corrosion reactions on the metallic matrix. Indeed, wet conditions promote the dissolution of metallic binder resulting in a potential synergic effect between the corrosion and wear mechanisms. The composition of the metallic matrix plays a key role on the stability of the coatings and their degradation rate. In this work, four coatings based on tungsten carbide embedded in different metallic binders were evaluated with regard to corrosion and wear. (author)

  13. 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

  14. 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...

  15. 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.

  16. 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...

  17. 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)

  18. 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.

  19. 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.

  20. Erosion-corrosion synergistics in the low erosion regime

    International Nuclear Information System (INIS)

    Corey, R.G.; Sethi, V.K.

    1986-01-01

    Many engineering alloys display good high temperature corrosion resistance. However, when they are used in corrosive environments where they are subjected to erosion also, the corrosion resistance has been adversely affected. The phenomenon known as erosion-corrosion is complex and requires detailed investigation of how the erosion and corrosion kinetics interact and compete. At the Kentucky Center for Energy Research Laboratory, an erosion-corrosion tester was used to perform erosion-oxidation tests on 2 1/4 Cr-1 Mo steel at 500-600 0 C using alumina abrasive at low velocities. The erosion-oxidation rate data and morphology of exposed surfaces are consistent with oxide chipping and fracturing being the mode of material loss

  1. A terminological matter: paragenesis, antigravitative erosion or antigravitational erosion ?

    Directory of Open Access Journals (Sweden)

    Pasini G.

    2009-07-01

    Full Text Available In the speleological literature three terms are utilized to designate the “ascending erosion”: paragenesis (= paragénésis, coined in1968, antigravitative erosion (= erosione antigravitativa, coined in 1966 and antigravitational erosion (wrong English translation ofthe Italian term erosione antigravitativa, utilized later on. The term paragenesis should be abandoned because of the priority of theterm erosione antigravitativa - on the ground of the “law of priority” – and because of its ambiguous etimology. On the other hand,the term antigravitational erosion should be forsaken in favour of the term antigravitative erosion, given the meaning that the termsgravitation and gravity have in Physics. Therefore, to designate the phenomenon of the “ascending erosion” there would be nothingleft but the term antigravitative erosion.The antigravitative erosion process and its recognizability are illustrated.Examples of caves with evident antigravitative erosion phenomena, developed in different karstifiable rocks and in several partsof the world, are given.It is recalled that the antigravitative erosion is a phenomenon well-known since 1942 and widely proven and supported, and that it isrelatively easy – in many cases - to recognize the antigravitative origin of karstic passages.It is stressed that the antigravitative erosion is an important phenomenon, exclusive of the karstic caves and unique in nature.

  2. 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.

  3. 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...

  4. 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

  5. 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

  6. 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.

  7. 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.

  8. 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

  9. 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

  10. 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 ...

  11. 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

  12. 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.

  13. 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

  14. 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

  15. 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.

  16. 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

  17. Erosion in extruder flow

    Science.gov (United States)

    Kaufman, Miron; Fodor, Petru S.

    A detailed analysis of the fluid flow in Tadmor's unwound channel model of the single screw extruder is performed by combining numerical and analytical methods. Using the analytical solution for the longitudinal velocity field (in the limit of zero Reynolds number) allows us to devote all the computational resources solely for a detailed numerical solution of the transversal velocity field. This high resolution 3D model of the fluid flow in a single-screw extruder allows us to identify the position and extent of Moffatt eddies that impede mixing. We further consider the erosion of particles (e.g. carbon-black agglomerates) advected by the polymeric flow. We assume a particle to be made of primary fragments bound together. In the erosion process a primary fragment breaks out of a given particle. Particles are advected by the laminar flow and they disperse because of the shear stresses imparted by the fluid. The time evolution of the numbers of particles of different sizes is described by the Bateman coupled differential equations used to model radioactivity. Using the particle size distribution we compute an entropic fragmentation index which varies from 0 for a monodisperse system to 1 for an extreme poly-disperse system.

  18. 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

  19. 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

  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. Rill erosion rates in burned forests

    Science.gov (United States)

    Joseph W. Wagenbrenner; Peter R. Robichaud

    2011-01-01

    Introduction Wildfires often produce large increases in runoff and erosion rates (e.g., Moody and Martin, 2009), and land managers need to predict the frequency and magnitude of postfire erosion to determine the needs for hazard response and possible erosion mitigation to reduce the impacts of increased erosion on public safety and valued resources. The Water Erosion...

  2. 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...

  3. Cavitation erosion resistance of diamond-like carbon coating on stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Feng; Jiang, Shuyun, E-mail: jiangshy@seu.edu.cn

    2014-02-15

    Two diamond-like carbon (DLC) coatings are prepared on stainless steel 304 by cathodic arc plasma deposition technology at different substrate bias voltages and arc currents (−200 V/80 A, labeled DLC-1, and −100 V/60 A, labeled DLC-2). Cavitation tests are performed by using a rotating-disk test rig to explore the cavitation erosion resistance of the DLC coating. The mass losses, surface morphologies, chemical compositions and the phase constituents of the specimens after cavitation tests are examined by using digital balance, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), respectively. The results indicate that the DLC-2 coatings can elongate the incubation period of stainless steel, leading to an excellent cavitation erosion resistance as compared to the untreated stainless steel specimens. After duration of 100 h cavitation test, serious damaged surfaces and plenty of scratches can be observed on the surfaces of the stainless steel specimens, while only a few grooves and tiny pits are observed on the DLC-2 coatings. It is concluded that, decreasing micro defects and increasing adhesion can reduce the delamination of DLC coating, and the erosion continues in the stainless steel substrate after DLC coating failure, and the eroded surface of the substrate is subjected to the combined action from cavitation erosion and slurry erosion.

  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. The erosive potential of lollipops

    NARCIS (Netherlands)

    Brand, H.S.; Gambon, D.L.; Paap, A.; Bulthuis, M.S.; Veerman, E.C.I.; Nieuw Amerongen, A.V.

    2009-01-01

    Aim: To determine the erosive potential of several commercially available lollipops and the protective effect of saliva. Methods: The erosive potential of lollipops was determined in vitro by measuring the pH and neutralisable acidity. Subsequently, 10 healthy volunteers tested different types of

  7. Wind erosion processes and control

    Science.gov (United States)

    Wind erosion continues to threaten the sustainability of our nations' soil, air, and water resources. To effectively apply conservation systems to prevent wind driven soil loss, an understanding of the fundamental processes of wind erosion is necessary so that land managers can better recognize the ...

  8. Erosion--corrosion

    International Nuclear Information System (INIS)

    Vyas, B.

    1978-01-01

    The deterioration of materials by corrosion or erosion by itself presents a formidable problem and for this reason investigators have studied these two phenomena independently. In fact, there are very few systematic studies on E-C and the majority of references mention it only in passing. In most real systems, however, the two destructive processes take place simultaneously, hence the purpose of this review is to present the various interactions between the chemical and mechanical agents leading to accelerated degradation of the material. The papers cited in the review are those that lead to a better understanding of the process involved in the accelerated rate of material loss under E-C conditions

  9. 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

  10. 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

  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. Using REE tracers to measure sheet erosion changing to rill erosion

    International Nuclear Information System (INIS)

    Liu Puling; Xue Yazhou; Song Wei; Wang Mingyi; Ju Tongjun

    2004-01-01

    Rare Earth Elements (REE) tracer method was used to study sheet erosion changing to rill erosion on slope land. By placing different rare earth elements of different soil depth across a slope in an indoor plot, two simulated rainfalls were applied to study the change of erosion type and the rill erosion process. The results indicate that the main erosion type is sheet erosion at the beginning of the rainfalls, and serious erosion happens after rill erosion appears. Accumulated sheet and rill erosion amounts increase with the rainfalls time. The percentage of sheet erosion amount decreases and rill erosion percentage increases with time. At the end of the rainfalls, the total rill erosion amounts are 4-5 times more than sheet erosion. In this paper, a new REE tracer method was used to quantitatively distinguish sheet and rill erosion amounts. The new REE tracer method should be useful to future studying of erosion processes on slope lands. (authors)

  13. Modeling soil erosion in a watershed

    OpenAIRE

    Lanuza, R.

    1999-01-01

    Most erosion models have been developed based on a plot scale and have limited application to a watershed due to the differences in aerial scale. In order to address this limitation, a GIS-assisted methodology for modeling soil erosion was developed using PCRaster to predict the rate of soil erosion at watershed level; identify the location of erosion prone areas; and analyze the impact of landuse changes on soil erosion. The general methodology of desktop modeling or soil erosion at watershe...

  14. The erosion performance of particle reinforced metal matrix composite coatings produced by co-deposition cold gas dynamic spraying

    Science.gov (United States)

    Peat, Tom; Galloway, Alexander; Toumpis, Athanasios; McNutt, Philip; Iqbal, Naveed

    2017-02-01

    This work reports on the erosion performance of three particle reinforced metal matrix composite coatings, co-deposited with an aluminium binder via cold-gas dynamic spraying. The deposition of ceramic particles is difficult to achieve with typical cold spray techniques due to the absence of particle deformation. This issue has been overcome in the present study by simultaneously spraying the reinforcing particles with a ductile metallic binder which has led to an increased level of ceramic/cermet particles deposited on the substrate with thick (>400 μm) coatings produced. The aim of this investigation was to evaluate the erosion performance of the co-deposited coatings within a slurry environment. The study also incorporated standard metallographic characterisation techniques to evaluate the distribution of reinforcing particles within the aluminium matrix. All coatings exhibited poorer erosion performance than the uncoated material, both in terms of volume loss and mass loss. The Al2O3 reinforced coating sustained the greatest amount of damage following exposure to the slurry and recorded the greatest volume loss (approx. 2.8 mm3) out of all of the examined coatings. Despite the poor erosion performance, the WC-CoCr reinforced coating demonstrated a considerable hardness increase over the as-received AA5083 (approx. 400%) and also exhibited the smallest free space length between adjacent particles. The findings of this study reveal that the removal of the AA5083 matrix by the impinging silicon carbide particles acts as the primary wear mechanism leading to the degradation of the coating. Analysis of the wear scar has demonstrated that the damage to the soft matrix alloy takes the form of ploughing and scoring which subsequently exposes carbide/oxide particles to the impinging slurry.

  15. 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

  16. 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...

  17. 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.

  18. 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.

  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. 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.

  1. 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

  2. Aerosol entrainment from a sparged non-Newtonian slurry

    International Nuclear Information System (INIS)

    Fritz, Brad G.

    2006-01-01

    Aerosol measurements were conducted above a half-scale air sparged mixing tank filled with simulated waste slurry. Three aerosol size fractions were measured at three sampling heights at three different sparging rates using a filter based ambient air sampling technique. Aerosol concentrations in the head space above the closed tank demonstrated a wide range, varying between 97 ?g m-3 for PM2.5 and 5650 ?g m-3 for TSP. The variation in concentrations was a function of sampling heights, size fraction and sparging rate. Measured aerosol entrainment coefficients showed good agreement with existing entrainment models. The models evaluated generally over predicted the entrainment, but were within a factor of two of the measured entrainment. This indicates that the range of applicability of the models may be extendable to include sparged slurries with Bingham plastic rheological properties

  3. An oilwell cement slurry additivated with bisphenol diglycidil ether/isophoronediamine-Kinetic analysis and multivariate modelings at slurry/HCl interfaces

    International Nuclear Information System (INIS)

    Cestari, Antonio R.; Vieira, Eunice F.S.; Tavares, Andrea M.G.; Andrade, Marcos A.S.

    2009-01-01

    Loss of zonal isolation in oilwell cementing operations leads to safety and environmental problems. The use of new cement slurries can help to solve this problem. In this paper, an epoxy-modified cement slurry was synthesized and characterized. The features of the modified slurries were evaluated in relation to a standard cement slurry (w/c = 0.50). A kinetic study of HCl interaction with the slurries was carried out using cubic molds. The Avrami kinetic model appears to be the most efficient in describing kinetic isotherms obtained from 25 to 55 deg. C. Type of slurry, HCl concentration and temperature effects were also evaluated in HCl adsorption onto cement slurries considering a 2 3 full factorial design. From the statistical analysis, it is inferred that the factor 'HCl concentration' has shown a profound influence on the numerical values of the Avrami kinetic constants. However, the best statistical fits were found using binary and tertiary interactive effects. It was found that the epoxy-modified cement slurry presents a good potential to be used in environmental-friendly oilwell operations.

  4. Slurry growth: the characterization of a unique phenomenon at the Hanford Site

    International Nuclear Information System (INIS)

    Jansky, M.T.

    1985-01-01

    Slurry growth, unique to the Hanford Site, is a significant increase in the volume of waste contained in a waste storage tank without the addition of new waste. Slurry growth is caused by gas entrapment within waste slurries which causes the slurry to swell, like bread dough. The surface of the slurry rises until either gas pressure is great enough or the weight of the slurry over the gases is great enough to cause the surface of the slurry to collapse. The gases causing slurry growth are generated from decomposition of organics present in high-level nuclear waste (HEDTA, EDTA, GLY). Predominant gases are H 2 , N 2 , N 2 O, NO/sub x/, and CO 2 . More gas is generated, and at a faster rate, as the temperature increases. Slurry growth, although not completely eliminated, is being safely and effectively controlled. The parameters affecting slurry growth have been defined, and predictive equations have been established. The knowledge gained through laboratory experiments contributes to continued safe and efficient high-level waste management practices at the Hanford Site

  5. Rheological properties of concentrated alumina slurries: influence of ph and dispersant agent

    International Nuclear Information System (INIS)

    Ewais, E.M.M.

    2004-01-01

    The relationship between the ph, the electrolyte concentrations and the rheological properties of high concentrated alumina slurries in aqueous medium is of great importance because it is considered to be the key to control the stability of the slurries from flocculation. Zeta potential of alumina slurries with and without Duramax C (dispersant agent) as a function of ph was studied. Two ph around the zero point of charge of alumina slurries were selected for the investigation of rheological properties. The rheological properties of aqueous alumina slurries with respect to different parameters, e.g.: viscosity, elastic modulus (storage modulus G) and viscous modulus (loss modulus G), were investigated. Viscosity measurements of the slurries as a function of Duramax C content at both ph 8.4 and 9.4) were used to determine the state of slurries. Three states of slurries, termed flocculated, partially de flocculated and fully de flocculated, were selected for further investigation. The viscosity of the three slurries at both ph as a function of shear rate was determined. Fully de flocculated slurry shows Newtonian behavior at all shear rates at both tested ph compared by the partial de flocculated and flocculated system. Results of investigation of G and G at ph of 9.4 as a function of applied stress explored the critical stress

  6. Viability of Ascaris suum eggs in stored raw and separated liquid slurry

    DEFF Research Database (Denmark)

    Katakam, Kiran Kumar; Roepstorff, Allan Knud; Popovic, Olga

    2013-01-01

    SUMMARY Separation of pig slurry into solid and liquid fractions is gaining importance as a way to manage increasing volumes of slurry. In contrast to solid manure and slurry, little is known about pathogen survival in separated liquid slurry. The viability of Ascaris suum eggs, a conservative...... indicator of fecal pollution, and its association with ammonia was investigated in separated liquid slurry in comparison with raw slurry. For this purpose nylon bags with 6000 eggs each were placed in 1 litre bottles containing one of the two fractions for 308 days at 5 °C or 25 °C. Initial analysis...... of helminth eggs in the separated liquid slurry revealed 47 Ascaris eggs per gramme. At 25 °C, egg viability declined to zero with a similar trend in both raw slurry and the separated liquid slurry by day 308, a time when at 5 °C 88% and 42% of the eggs were still viable in separated liquid slurry and raw...

  7. 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)

  8. Gastric Mucosal Erosions - Radiologic evaluation -

    International Nuclear Information System (INIS)

    Kim, Seung Hyup

    1985-01-01

    70 cases of gastric mucosal erosions were diagnosed by double contrast upper gastrointestinal examinations and endoscopic findings. Analyzing the radiologic findings of these 70 cases of gastric mucosal erosions, the following results were obtained. 1. Among the total 70 cases, 65 cases were typical varioliform erosions showing central depressions and surrounding mucosal elevations. Remaining 5 cases were erosions of acute phase having multiple irregular depressions without surrounding elevations. 2. The gastric antrum was involved alone or in part in all cases. Duodenal bulb was involved with gastric antrum in 4 cases. 3. The majority of the cases had multiple erosions. There were only 2 cases of single erosion. 4. In 65 cases of varioliform erosions; 1) The diameter of the surrounding elevations varied from 3 to 20 mm with the majority (47 cases) between 6 and 10 mm. 2) In general, the surrounding elevations with sharp margin on double contrast films were also clearly demonstrated on compression films but those with faint margin were not. 3) The size of the central barium collections varied from pinpoint to 10 mm with the majority under 5 mm. The shape of the central barium collections in majority of the cases were round with a few cases of linear, triangular or star-shape. 5. In 5 cases of acute phase erosions; 1) All the 5 cases were females. 2) On double contrast radiography, all the cases showed multiple irregular depressed lesions without surrounding elevations. 3) 1 case had the history of hematemesis. 4) In 1 case, there was marked radiological improvement on follow-up study of 2 months interval. 6. In 23 cases, there were coexistent diseases with gastric mucosal erosions. These were 13 cases of duodenal bulb ulcers,7 cases of benign gastric ulcers and 3 others

  9. Piston membrane pumps for slurries transport; Kolbenmembranpumpen fuer den Schlammtransport

    Energy Technology Data Exchange (ETDEWEB)

    Wiechmann, F. [Abel GmbH und Co. KG, Buechen (Germany)

    2006-03-15

    As raw materials prices are rising, ore and coal mines in remote parts of the world have become profitable. Local infrastructures in these regions are not comparable with Europe. There are no rods or railways, and pipelines must be constructed parallel to rivers through deserts, mountains and rainforests. As a rule, pipelines do not follow favourable geological conditions but are constructed along the shortest possible rout to the nearest port or the nearest processing plant. Slurries are transported by pumping. (orig.)

  10. Radioactive slurry waste treatment (1) - flucculant 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

    During the past four decades, the radioactive slurry liquid waste(RSLW) is produced by operation of TRIGA Mark - II and III research reactors, producing radioisotopes and studying on RI utilization. Vacuum filtration of RSLW and flocculated RSLW with cationic, anionic and nonionic flocculants has been investigated. Test results show that critical dose of flocculant is obtained by the estimation of settling rate, cake moisture content and specific cake residence

  11. Putting the coal slurry pipelines to the test

    Energy Technology Data Exchange (ETDEWEB)

    Sauermann, H B

    1978-03-01

    This paper deals with the advantages and disadvantages of coal slurry pipelines and describes coal slurry tests undertaken in three test circuits with 100, 200 and 250 mm diameter pipes. The test results from the test circuits were used to scale-up pressure gradients to larger pipe diameters. The construction and installation of hydraulic transport pipelines is simple and requires a minimum of space. The crossing of rivers, roads, railways or any other obstacles is comparatively easy. The operation, supervision and maintenance of a pipeline is simple since any pipeline can be easily adapted for fully automatic control. For this reason manpower requirements are small resulting in only small increases in operating costs during the life of a pipeline. This is an attractive feature in any economy troubled by inflationary trends. In transporting a commodity such as coal the quantities handled are usually large and the distances are long. The profitability of hydraulic transportation systems benefits from such operating conditions. Even though the various components of a slurry transport system, such as the slurrying facilities at the mine end and the dewatering facilities at the utilization end, are complex, their reliability is high. Against the advantages, the following limitations can be visualized: It is practically impossible to transport solids other than those for which the pipeline was designed; in this regard, road and rail transportation is more versatile. The solids throughput through a pipeline cannot be economically increased beyond its design throughput. Pipelining involves the use of fluids, in most cases water, which in some instances may not be readily available.

  12. Process for the preparation of a thickened explosive slurry

    Energy Technology Data Exchange (ETDEWEB)

    1972-10-25

    A process is described for the preparation of a thickened explosive slurry, substantially aqueous. The composition consists essentially of a suspension of an inorganic oxygen salt for furnishing oxygen in a fluid matrix. This fluid matrix consists of a lower aliphatic glycol (ethylene, diethylene, propylene, dipropylene) thickened with one of the polysaccharides (glucose, mannose, galactose) or mixtures of them. The composition should have a density below 1.8 g per cu cm. (5 claims)

  13. Atomization of JP-10/B4C gelled slurry fuel

    OpenAIRE

    Guglielmi, John David

    1992-01-01

    The atomization of a gelled boron slurry fuel using two commercially available airblast atomizers was studied at atmospheric pressure in non-reacting flow. The atomization of water was also characterized for comparison. Each atomizer was operated at two different liquid mass flow rates and several air/ fuel ratios. Drop size distribution was measured using a Malvern 2600 HSD Laser Diffraction Particle Sizer, Drop sizes acceptable for use in ramjet combustors could be obtained f...

  14. Design of agitation systems in Bingham slurries by pilot simulation

    International Nuclear Information System (INIS)

    Nielsen, M.G.

    1987-01-01

    A method was required to determine the optimum agitator speed needed to produce overall motion of the Defense Waste Processing Facility (DWPF) high-level waste slurries in remote process cell vessels. Project schedule and limited process space required an accurate determination of agitator horsepower and size without the benefit of full-scale testing. The small scale testing of unique clear rheologically similar fluid is described along with tests and scale-up procedures. 2 refs., 3 figs

  15. Buffer erosion in dilute groundwater

    International Nuclear Information System (INIS)

    Schatz, T.; Kanerva, N.; Martikainen, J.; Sane, P.; Olin, M.; Seppaelae, A.; Koskinen, K.

    2013-08-01

    One scenario of interest for repository safety assessment involves the loss of bentonite buffer material in contact with dilute groundwater flowing through a transmissive fracture interface. In order to examine the extrusion/erosion behavior of bentonite buffer material under such circumstances, a series of experiments were performed in a flow-through, 1 mm aperture, artificial fracture system. These experiments covered a range of solution chemistry (salt concentration and composition), material composition (sodium montmorillonite and admixtures with calcium montmorillonite), and flow velocity conditions. No erosion was observed for sodium montmorillonite against solution compositions from 0.5 g/L to 10 g/L NaCl. No erosion was observed for 50/50 calcium/sodium montmorillonite against 0.5 g/L NaCl. Erosion was observed for both sodium montmorillonite and 50/50 calcium/sodium montmorillonite against solution compositions ≤ 0.25 g/L NaCl. The calculated erosion rates for the tests with the highest levels of measured erosion, i.e., the tests run under the most dilute conditions (ionic strength (IS) < ∼1 mM), were well-correlated to flow velocity, whereas the calculated erosion rates for the tests with lower levels of measured erosion, i.e., the tests run under somewhat less dilute conditions (∼1 mM < IS < ∼4 mM), were not similarly correlated indicating that material and solution composition can significantly affect erosion rates. In every experiment, both erosive and non-erosive, emplaced buffer material extruded into the fracture and was observed to be impermeable to water flowing in the fracture effectively forming an extended diffusive barrier around the intersecting fracture/buffer interface. Additionally, a model which was developed previously to predict the rate of erosion of bentonite buffer material in low ionic strength water in rock fracture environments was applied to three different cases: sodium montmorillonite expansion in a vertical tube, a

  16. 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

  17. Surfactant mediated slurry formulations for Ge CMP applications

    KAUST Repository

    Basim, G. Bahar

    2013-01-01

    In this study, slurry formulations in the presence of self-assembled surfactant structures were investigated for Ge/SiO2 CMP applications in the absence and presence of oxidizers. Both anionic (sodium dodecyl sulfate-SDS) and cationic (cetyl trimethyl ammonium bromide-C12TAB) micelles were used in the slurry formulations as a function of pH and oxidizer concentration. CMP performances of Ge and SiO2 wafers were evaluated in terms of material removal rates, selectivity and surface quality. The material removal rate responses were also assessed through AFM wear rate tests to obtain a faster response for preliminary analyses. The surfactant adsorption characteristics were studied through surface wettability responses of the Ge and SiO2 wafers through contact angle measurements. It was observed that the self-assembled surfactant structures can help obtain selectivity on the silica/germanium system at low concentrations of the oxidizer in the slurry. © 2013 Materials Research Society.

  18. Automation of the second iron ore slurry pipeline from Samarco

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar, Juliana M.; Fonseca, Mario L.; Drumond, Pablo P.; Barbosa, Sylvio [IHM Engenharia, Belo Horizonte, MG (Brazil)

    2009-07-01

    The second iron ore slurry pipeline from Samarco was build to attend the Third Pellet Plant Project, which includes a new Concentration Plant at Germano-MG and a third Pellet Plant at Ubu-ES. It has 396km of extension and links the two plants by pulping the iron ore slurry prepared at Germano Unit. This works aims to present the iron ore slurry pipeline with emphasis on the automation architecture for the supervision and control system, interconnect throughout the pipe extension by fiber optics. The control system is composed of ControlLogix CLP's at the pulping and valve station and Micrologix CLP's at the pressure and cathodic protection monitoring points, totalizing 19 PLC's. The supervisory system was developed using the Wonderware IAS 3.0 suite, including the supervisory software InTouch 9.5 and the integrated ArchestrA IDE, and is composed of two data servers in redundancy and nine operation stations. The control and supervision system is interconnect through and Ethernet network using fiber optics and multiplexer modules (GE JungleMux) for voice, data and video. Among the expected results, it can be highlighted the sequence automation, greater process data availability (real and historical) and greater facility for the operation and detection of failures. (author)

  19. Superheated fuel injection for combustion of liquid-solid slurries

    Science.gov (United States)

    Robben, F.A.

    1984-10-19

    A method and device are claimed for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel is heated under pressure to near critical temperature in an injector accumulator, where the pressure is sufficiently high to prevent boiling. After injection into a combustion chamber, the water temperature will be well above boiling point at a reduced pressure in the combustion chamber, and flash boiling will preferentially take place at solid-liquid surfaces, resulting in the shattering of water droplets and the subsequent separation of the water from coal particles. This prevents the agglomeration of the coal particles during the subsequent ignition and combustion process, and reduces the energy required to evaporate the water and to heat the coal particles to ignition temperature. The overall effect will be to accelerate the ignition and combustion rates, and to reduce the size of the ash particles formed from the coal. 2 figs., 2 tabs.

  20. Efficient filtration system for paraffin-catalyst slurry separation

    Directory of Open Access Journals (Sweden)

    Khodagholi Mohammad Ali

    2013-01-01

    Full Text Available The filtration efficiency for separating liquid paraffin (or water from a slurry consisting of 25 weight% spherical alumina in a Slurry Bubble Column Reactor (SBCR comprised of a cylindrical tube of 10 cm diameter and 150 cm length was studied. Various differential pressures (ΔP were applied to two separate tubular sintered metal stainless steel filter elements with nominal pore size of 4 and 16μm. The experimental results disclosed that the rate of filtrations increased on applying higher differential pressure to the filter element. Albeit this phenomenon is limited to moderate ΔPs and for ΔP more than 1 bar is neither harmful nor helpful. The highest filtration rates at ΔPs higher than 1 bar were 170 and 248 ml/minute for 4 and 16μm respectively. Using water as the liquid in slurry the rate of filtration enhanced to 4 folds, and this issue reveals impact of viscosity on filtration efficiency clearly. In all situations, the total amount of particles present in the filtrate part never exceeded a few parts per million (ppm. The statistical analysis of the SEM image of the filtrate indicated that by applying higher pressure difference to the filter element the frequency percent of larger particle size increases. The operation of filter cake removing was performed with back flashing of 300 ml of clean liquid with pressures of 3-5 bar of N2 gas.

  1. 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

  2. Erosive tooth wear in children

    NARCIS (Netherlands)

    Carvalho, T.S.; Lussi, A.; Jaeggi, T.; Gambon, D.L.; Lussi, A.; Ganss, C.

    2014-01-01

    Erosive tooth wear in children is a common condition. Besides the anatomical differences between deciduous and permanent teeth, additional histological differences may influence their susceptibility to dissolution. Considering laboratory studies alone, it is not clear whether deciduous teeth are

  3. Erosion-resistant composite material

    Science.gov (United States)

    Finch, C.B.; Tennery, V.J.; Curlee, R.M.

    A highly erosion-resistant composite material is formed of chemical vapor-deposited titanium diboride on a sintered titanium diboride-nickel substrate. This material may be suitable for use in cutting tools, coal liquefaction systems, etc.

  4. Soil Erosion and Agricultural Sustainability

    Science.gov (United States)

    Montgomery, D. R.

    2009-04-01

    Data drawn from a global compilation of studies support the long articulated contention that erosion rates from conventionally plowed agricultural fields greatly exceed rates of soil production, erosion under native vegetation, and long-term geological erosion. Whereas data compiled from around the world show that soil erosion under conventional agriculture exceeds both rates of soil production and geological erosion rates by up to several orders of magnitude, similar global distributions of soil production and geological erosion rates suggest an approximate balance. Net soil erosion rates in conventionally plowed fields on the order of 1 mm/yr can erode typical hillslope soil profiles over centuries to millennia, time-scales comparable to the longevity of major civilizations. Well-documented episodes of soil loss associated with agricultural activities date back to the introduction of erosive agricultural methods in regions around the world, and stratigraphic records of accelerated anthropogenic soil erosion have been recovered from lake, fluvial, and colluvial stratigraphy, as well as truncation of soil stratigraphy (such as truncated A horizons). A broad convergence in the results from studies based on various approaches employed to study ancient soil loss and rates of downstream sedimentation implies that widespread soil loss has accompanied human agricultural intensification in examples drawn from around the world. While a broad range of factors, including climate variability and society-specific social and economic contexts — such as wars or colonial relationships — all naturally influence the longevity of human societies, the ongoing loss of topsoil inferred from studies of soil erosion rates in conventional agricultural systems has obvious long-term implications for agricultural sustainability. Consequently, modern agriculture — and therefore global society — faces a fundamental question over the upcoming centuries. Can an agricultural system

  5. Erosion properties of unipolar arcs

    International Nuclear Information System (INIS)

    Chekalin, Eh.K.

    1982-01-01

    Processes modelling the formation of unipolar arcs on the elements of the first wall in limiters of the vacuum chamber and on active elements of tokamak divertor, are experimentally investigated. Erosion, processes that take place at two types of non-stationary cathode spots are considered. Experimental data prove the possibility of reducing erosion intensity by coating the surface of electrodes by oxide films, reduction of the temperature of electrode and discharge current

  6. In-situ study of the thermal properties of hydrate slurry by high pressure DSC

    Energy Technology Data Exchange (ETDEWEB)

    Sari, O.; Hu, J.; Brun, F.; Erbeau, N. [Institute of Thermal Engineering, University of Applied Sciences of Western Switzerland, Yverdon-les-Bains (Switzerland); Homsy, P. [Nestec, Vevey (Switzerland); Logel, J.-C. [Axima Refrigeration, Bischheim (France)

    2008-07-01

    Knowing the enthalpy of hydrate slurry is very essential for energy balance and industrial applications. No direct measurement processes had been developed in this field in the past time. A new experimental method with special device has been developed to carry out on-line measurement of the thermal properties for hydrate slurry under dynamic conditions. With this special device, it is possible to deliver the hydrate slurry to the high pressure DSC (Differential Scanning Calorimetry) directly from the production tank or pipes. Thermal data acquisition will be performed afterwards by DSC. The investigated conditions were at pressure of 30 bar and temperature of {approx}+7 {sup o}C. The dissociation enthalpy of CO{sub 2} hydrate slurry was about 54 kJ/kg, corresponding 10.8% of solid fraction. The on-line measurement results for CO{sub 2} hydrate slurry give a good tendency to apply this phase change slurry to the industrial refrigeration process. (author)

  7. Analysis of high-level radioactive slurries as a method to reduce DWPF turnaround times

    International Nuclear Information System (INIS)

    Coleman, C.J.; Bibler, N.E.; Ferrara, D.M.; Hay, M.S.

    1996-01-01

    Analysis of Defense Waste Processing Facility (DWPF) samples as slurries rather than as dried or vitrified samples is an effective way to reduce sample turnaround times. Slurries can be dissolved with a mixture of concentrated acids to yield solutions for elemental analysis by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Slurry analyses can be performed in eight hours, whereas analyses of vitrified samples require up to 40 hours to complete. Analyses of melter feed samples consisting of the DWPF borosilicate frit and either simulated or actual DWPF radioactive sludge were typically within a range of 3--5% of the predicted value based on the relative amounts of sludge and frit added to the slurry. The results indicate that the slurry analysis approach yields analytical accuracy and precision competitive with those obtained from analyses of vitrified samples. Slurry analyses offer a viable alternative to analyses of solid samples as a simple way to reduce analytical turnaround times

  8. Enhancing protein to extremely high content in photosynthetic bacteria during biogas slurry treatment.

    Science.gov (United States)

    Yang, Anqi; Zhang, Guangming; Meng, Fan; Lu, Pei; Wang, Xintian; Peng, Meng

    2017-12-01

    This work proposed a novel approach to achieve an extremely high protein content in photosynthetic bacteria (PSB) using biogas slurry as a culturing medium. The results showed the protein content of PSB could be enhanced strongly to 90% in the biogas slurry, which was much higher than reported microbial protein contents. The slurry was partially purified at the same time. Dark-aerobic was more beneficial than light-anaerobic condition for protein accumulation. High salinity and high ammonia of the biogas slurry were the main causes for protein enhancement. In addition, the biogas slurry provided a good buffer system for PSB to grow. The biosynthesis mechanism of protein in PSB was explored according to theoretical analysis. During biogas slurry treatment, the activities of glutamate synthase and glutamine synthetase were increased by 26.55%, 46.95% respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Effects of storage time and straw content of cattle slurry on the mineralization of nitrogen and carbon in soil

    DEFF Research Database (Denmark)

    Sørensen, P.

    1998-01-01

    Animal slurries are stored for a variable period of time before application in the field. The effect of cattle slurry storage time and temperature on the subsequent mineralization of C and N in soil was studied under laboratory conditions. Urine and faeces from a dairy cow were sampled separately...... and mixed to a slurry. After 4 weeks of storage under anaerobic conditions at 15 degrees C, the NH4+ N content exceeded the original urinary N content of the slurry; the NH4+ content increased only slightly during the following 16 weeks of storage. After 4 weeks of storage, the proportion of slurry C...... in volatile fatty acids (VFA) amounted to 10% and increased to 15% after 20 weeks. Straw addition to the slurry caused an increase of VFA-C in stored slurry, but had a negligible influence on the proportion of slurry N in the form of NH4+. Slurries subjected to different storage conditions were added...

  10. Wind erosion of soils burned by wildfire

    Science.gov (United States)

    N. S. Wagenbrenner; M. J. Germino; B. K. Lamb; R. B. Foltz; P. R. Robichaud

    2011-01-01

    Wind erosion and aeolian transport processes are largely unstudied in the post-wildfire environment, but recent studies have shown that wind erosion can play a major role in burned landscapes. A wind erosion monitoring system was installed immediately following a wildfire in southeastern Idaho, USA to measure wind erosion from the burned area (Figure 1). This paper...

  11. The effect of particle size and concentration on the flow properties of a homogeneous slurry

    International Nuclear Information System (INIS)

    Abbas, M.A.; Crowe, C.T.

    1986-01-01

    This paper presents the results of the effects of particle size and concentration on the velocity distribution in the fully developed flow of a homogeneous slurry. The slurry consisted of chloroform and silica gel with matched index of refraction to enable Laser-Doppler anemometry (LDA) measurements through the mixture. Slurries with two particle sizes and solids concentration up to 30% by volume were studied. Measurements were made over a Reynolds number range of 1,200 to 30,000

  12. Effect of plastic viscosity and yield value on spray characteristics of magnesium-slurry fuel

    Science.gov (United States)

    Prok, George M

    1957-01-01

    Magnesium slurries were sprayed onto a sheet of paper from an air-atomizing injector. Drop sizes and distributions were then determined from photomicrographs. Four different surface-active additives were used in preparing the slurries to give plastic viscosities between 0.22 and 0.51 poise and yield values between 150 and 810 dynes-cm(exp 2). It was found that there was no significant variation in the spray characteristics of these slurries when tested under the same conditions.

  13. Aerobic Biological treatment of municipal wastewaters and pig slurry and the associated bacteriological and parasitological risks

    Energy Technology Data Exchange (ETDEWEB)

    Venglovsky, J.; Sasokova, N.; Juris, P.; Papajova, I.; Vargova, M.; Ondrasovicova, O.; Ondrasovic, M.

    2009-07-01

    The aim of the present study was to investigate the bacteriological and parasitological risk associated with the products of aerobic treatment of pig slurry and municipal sewage. We focused on the quality of effluents and on sewage sludge and pig slurry solids from two wastewater treatment plants (pig slurry WWTP.1; municipal wastewater WWTP-2 with regard to place counts of selected groups of bacteria (mesophilic, coliform, faecal coliform) and the efficiency of their removal. (Author)

  14. Aerobic Biological treatment of municipal wastewaters and pig slurry and the associated bacteriological and parasitological risks

    International Nuclear Information System (INIS)

    Venglovsky, J.; Sasokova, N.; Juris, P.; Papajova, I.; Vargova, M.; Ondrasovicova, O.; Ondrasovic, M.

    2009-01-01

    The aim of the present study was to investigate the bacteriological and parasitological risk associated with the products of aerobic treatment of pig slurry and municipal sewage. We focused on the quality of effluents and on sewage sludge and pig slurry solids from two wastewater treatment plants (pig slurry WWTP.1; municipal wastewater WWTP-2 with regard to place counts of selected groups of bacteria (mesophilic, coliform, faecal coliform) and the efficiency of their removal. (Author)

  15. TEMPEST code modifications and testing for erosion-resisting sludge simulations

    International Nuclear Information System (INIS)

    Onishi, Y.; Trent, D.S.

    1998-01-01

    The TEMPEST computer code has been used to address many waste retrieval operational and safety questions regarding waste mobilization, mixing, and gas retention. Because the amount of sludge retrieved from the tank is directly related to the sludge yield strength and the shear stress acting upon it, it is important to incorporate the sludge yield strength into simulations of erosion-resisting tank waste retrieval operations. This report describes current efforts to modify the TEMPEST code to simulate pump jet mixing of erosion-resisting tank wastes and the models used to test for erosion of waste sludge with yield strength. Test results for solid deposition and diluent/slurry jet injection into sludge layers in simplified tank conditions show that the modified TEMPEST code has a basic ability to simulate both the mobility and immobility of the sludges with yield strength. Further testing, modification, calibration, and verification of the sludge mobilization/immobilization model are planned using erosion data as they apply to waste tank sludges

  16. Anaerobic digestion as a slurry management strategy : a consequential life cycle assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hamelin, L.; Wesnaes, M.; Wenzel, H.; Petersen, B.M. [Southern Denmark Univ. (Denmark). Inst. of Chemical Engineering, Biotechnology and Environmental Technology

    2010-07-01

    Anaerobic digestion of slurry represents an environmental opportunity for both slurry management and renewable energy production in countries with high animal density. This study evaluated the environmental impacts of 4 biogas production alternatives in which slurry was the only input in the process, without supplementary addition of easily degradable carbon. This was achieved by exposing the slurry to different separation technologies. The biomass mixture input for biogas production included solid fraction from slurry separation as well as raw slurry, proportioned in order to achieve economical methane yield. The separation processes considered in this study were mechanical separation; mechanical separation combined with the addition of flocculants; and mechanical separation combined with a thermal treatment. Four biogas alternatives were compared to a reference slurry management scenario, notably to use the slurry as a fertilizer without prior treatment. The modelling was based on Danish conditions and used the consequential life cycle assessment methodology. The produced biogas was used for production of heat and power and the degassed slurry was used as an organic fertilizer.

  17. Development of peat-oil (POM) and peat-alcohol (PAM) slurries as alternative fuels

    Energy Technology Data Exchange (ETDEWEB)

    Clemens, D F

    1983-11-01

    The preparation and evaluation of peat/No. 2 fuel oil mixtures (POM) and peat/methanol mixtures (PAM) is described. POM and PAM prepared using North Carolina peat and having varied peat loadings, peat moisture contents and peat particle sizes have been studied by measuring slurry sedimentation ratios and drain times from sedimentation tubes. The peat moisture content was particularly crucial in forming stable slurries. The effect of a variety of additives at 0.5-1.0 wt% on sedimentation ratios, drain times and viscosities was studied. Calorimetric studies of several PAM and POM slurries as well as preliminary combustion tests of POM slurries in a salamander burner are also reported.

  18. The development of peat-oil (POM) and peat-alcohol (PAM) slurries as alternative fuels

    Energy Technology Data Exchange (ETDEWEB)

    Clemens, D F; Evans, G O; Harrell, P A; Whitehurst, B M

    1983-11-01

    The preparation and evaluation of peat/No. 2 fuel oil mixtures (POM) and peat/methanol mixtures (PAM) is described. POM and PAM prepared using North Carolina peat and having varied peat loadings, peat moisture contents, and peat particle sizes have been studied by measuring slurry sedimentation ratios and drain times from sedimentation tubes. The peat moisture content was particularly crucial in forming stable slurries. The effect of a variety of additives at 0.5-1.0 wt.% on sedimentation ratios, drain times, and viscosities was studied. Calorimetric studies of several PAM and POM slurries as well as preliminary combustion tests of POM slurries in a salamander burner are also reported.

  19. Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries

    Science.gov (United States)

    Doherty, J.P.; Marek, J.C.

    1987-02-25

    A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper(II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the original organic compounds, is subsequently blended with high level radioactive sludge land transferred to a vitrification facility for processing into borosilicate glass for long-term storage. 2 figs., 3 tabs.

  20. Flow velocity analysis for avoidance of solids deposition during transport of Hanford tank waste slurries

    International Nuclear Information System (INIS)

    ESTEY, S.D.

    1999-01-01

    This engineering analysis calculates minimum slurry transport velocities intended to maintain suspensions of solid particulate in slurries. This transport velocity is also known as the slurry flow critical velocity. It is not universally recognized that a transfer line flow velocity in excess of the slurry critical velocity is a requirement to prevent solids deposition and possible line plugging. However, slurry critical velocity seems to be the most prevalent objective measure to prevent solids deposition in transfer lines. The following critical velocity correlations from the literature are investigated: Durand (1953), Spells (1955), Sinclair (1962), Zandi and Gavatos (1967), Babcock (1968), Shook (1969), and Oroskar and Turian (1980). The advantage of these critical velocity correlations is that their use is not reliant upon any measure of bulk slurry viscosity. The input parameters are limited to slurry phase densities and mass fractions, pipe diameter, particle diameter, and viscosity of the pure liquid phase of the slurry. Consequently, the critical velocity calculation does not require determination of system pressure drops. Generalized slurry properties can, therefore, be recommended if the slurry can be adequately described by these variables and if the liquid phase viscosity is known. Analysis of these correlations are presented, indicating that the Oroskar and Turian (1980) models appear to be more conservative for smaller particulate sizes, typically those less than 100 microns diameter. This analysis suggests that the current Tank Farms waste compatibility program criteria may be insufficient to prevent particulate solids settling within slurry composition ranges currently allowed by the waste compatibility program. However, in order to relate a critical velocity associated with a certain slurry composition to a system limit, a means of relating the system capabilities to the slurry composition must be found. Generally, this means expressing the bulk

  1. 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

  2. Vitrification of SRP waste by a slurry-fed ceramic melter

    International Nuclear Information System (INIS)

    Wicks, G.G.

    1980-01-01

    Savannah River Plant (SRP) high-level waste (HLW) can be vitrified by feeding a slurry, instead of a calcine, to a joule-heated ceramic melter. Potential advantages of slurry feeding include (1) use of simpler equipment, (2) elimination of handling easily dispersed radioactive powder, (3) simpler process control, (4) effective mixing, (5) reduced off-gas volume, and (6) cost savings. Assessment of advantages and disadvantages of slurry feeding along with experimental studies indicate that slurry feeding is a promising way of vitrifying waste

  3. Soil slurry reactors for the assessment of contaminant biodegradation

    Science.gov (United States)

    Toscano, G.; Colarieti, M. L.; Greco, G.

    2012-04-01

    Slurry reactors are frequently used in the assessment of feasibility of biodegradation in natural soil systems. The rate of contaminant removal is usually quantified by zero- or first-order kinetics decay constants. The significance of such constants for the evaluation of removal rate in the field could be questioned because the slurry reactor is a water-saturated, well-stirred system without resemblance with an unsaturated fixed bed of soil. Nevertheless, a kinetic study with soil slurry reactors can still be useful by means of only slightly more sophisticated kinetic models than zero-/first-order decay. The use of kinetic models taking into account the role of degrading biomass, even in the absence of reliable experimental methods for its quantification, provides further insight into the effect of nutrient additions. A real acceleration of biodegradation processes is obtained only when the degrading biomass is in the growth condition. The apparent change in contaminant removal course can be useful to diagnose biomass growth without direct biomass measurement. Even though molecular biology techniques are effective to assess the presence of potentially degrading microorganism in a "viable-but-nonculturable" state, the attainment of conditions for growth is still important to the development of enhanced remediation techniques. The methodology is illustrated with reference to data gathered for two test sites, Oslo airport Gardermoen in Norway (continuous contamination by aircraft deicing fluids) and the Trecate site in Italy (aged contamination by crude oil spill). This research is part of SoilCAM project (Soil Contamination, Advanced integrated characterisation and time-lapse Monitoring 2008-2012, EU-FP7).

  4. Auto consolidated cohesive sediments erosion

    International Nuclear Information System (INIS)

    Ternat, F.

    2007-02-01

    Pollutants and suspended matters of a river can accumulate into the sedimentary column. Once deposited, they are submitted to self-weight consolidation processes, ageing and burying, leading to an increase of their erosion resistance. Pollutant fluxes can be related to sedimentary fluxes, determined by threshold laws. In this work, an erosion threshold model is suggested by introducing a cohesion force into the usual force balance. A model of cohesion is developed on the basis of interactions between argillaceous cohesive particles (clays), particularly the Van der Waals force, whose parameterization is ensured by means of granulometry and porosity. Artificial erosion experiments were performed in a recirculating erosion flume with natural cored sediments where critical shear stress measurements were performed. Other analyses provided granulometry and porosity. The results obtained constitute a good database for the literature. The model is then applied to the experimental conditions and gives good agreement with measurements. An example of the accounting for self-weight consolidation processes is finally suggested, before finishing on a Mohr like diagram dedicated to soft cohesive sediment erosion. (author)

  5. Influence of soil structure on contaminant leaching from injected slurry.

    Science.gov (United States)

    Amin, M G Mostofa; Pedersen, Christina Østerballe; Forslund, Anita; Veith, Tamie L; Laegdsmand, Mette

    2016-12-15

    Animal manure application to agricultural land provides beneficial organic matter and nutrients but can spread harmful contaminants to the environment. Contamination of fresh produce, surface water and shallow groundwater with the manure-borne pollutants can be a critical concern. Leaching and persistence of nitrogen, microorganisms (bacteriophage, E. coli, and Enterococcus) and a group of steroid hormone (estrogens) were investigated after injection of swine slurry into either intact (structured) or disturbed (homogeneous repacked) soil. The slurry was injected into hexaplicate soil columns at a rate of 50 t ha -1 and followed with four irrigation events: 3.5-h period at 10 mm h -1 after 1, 2, 3, and 4 weeks. The disturbed columns delayed the leaching of a conservative tracer and microorganisms in the first irrigation event compared to the intact columns due to the effect of disturbed macropore flow paths. The slurry constituents that ended up in or near the macropore flow paths of the intact soil were presumably washed out relatively quickly in the first event. For the last three events the intact soil leached fewer microorganisms than the disturbed soil due to the bypassing effect of water through the macropore flow path in the intact soil. Estrogen leached from the intact soil in the first event only, but for the disturbed soil it was detected in the leachates of last two events also. Leaching from the later events was attributed to higher colloid transport from the disturbed soils. In contrast, NO 3 -N leaching from the intact soil was higher for all events except the first event, probably due to a lower nitrification rate in the disturbed soil. A week after the last irrigation event, the redistribution of all slurry constituents except NO 3 -N in most of the sections of the soil column was higher for the disturbed soil. Total recovery of E. coli was significantly higher from the disturbed soil and total leaching of mineral nitrogen was significantly

  6. It's sensible to mix your own slurries

    Energy Technology Data Exchange (ETDEWEB)

    Chironis, N.P.

    1990-05-01

    Slurry explosives have not made the gains in the market expected of them, possibly due to the extra handling required at the mine site. One Peabody Coal Co. mine has built its own inexpensive setup that blends emulsions with Anfo to the desired ratio before loading the blend into Anfo trucks. Another mine is using a salvaged cement mixer to mix up its own batches of water gels, which are then mixed with Anfo. Both approaches result in blends that can be specialized for different areas of a mine to expand drill patterns, increase fragmentation and gain additional movements for blast casting. 2 figs.

  7. Slurry pipelines: economic and political issues. A review

    Energy Technology Data Exchange (ETDEWEB)

    Banks, W. F.

    1977-11-30

    In the controversy surrounding the proposal to grant Federal eminent domain to coal-slurry pipelines, the fundamental issue is whether, on balance, such a grant is in the national interest. The principal subissues (peripheral issues) of economics, water supply and disposal, energy consumption and conservation, employment, safety, and environmental impact are analyzed. It is found that, as compared with unit trains, which are the only immediate alternative for movement of large quantities of Western coal, the pipelines are not against the national interest, except in the case of employment. It is concluded that, on balance, the pipelines are in the national interest and should be granted the power of Federal eminent domain.

  8. Deep conversion of black oils with Eni Slurry technology

    Energy Technology Data Exchange (ETDEWEB)

    Panariti, Nicoletta; Rispoli, Giacomo

    2010-09-15

    Eni Slurry Technology represents a significant technological innovation in residue conversion and unconventional oils upgrading. EST allows the almost total conversion of heavy feedstocks into useful products, mainly transportation fuels, with a great major impact on the economic and environmental valorization of hydrocarbon resources. The peculiar characteristics of EST in terms of yields, products quality, absence of undesired by-products and feedstock flexibility constitute its superior economic and environmental attractiveness. The first full scale industrial plant based on this new technology will be realized in Eni's Sannazzaro refinery (23,000 bpd). Oil in is scheduled by 4th quarter 2012.

  9. Relationships among slurry characteristics and gaseous emissions at different types of commercial Spanish pig farms

    Energy Technology Data Exchange (ETDEWEB)

    Becaccia, A.; Ferrer, P.; Ibañez, M.A.; Estellés, F.; Rodríguez, C.; Moset, V.; Blas, C. de; Calvet, P.; García-Rebollar, P.

    2015-07-01

    This study aimed to analyse several factors of variation of slurry composition and to establish prediction equations for potential methane (CH4) and ammonia (NH3) emissions. Seventy-nine feed and slurry samples were collected at two seasons (summer and winter) from commercial pig farms sited at two Spanish regions (Centre and Mediterranean). Nursery, growing-fattening, gestating and lactating facilities were sampled. Feed and slurry composition were determined, and potential CH4 and NH3 emissions measured at laboratory. Feed nutrient contents were used as covariates in the analysis. Near infrared reflectance spectroscopy (NIRS) was evaluated as a predicting tool for slurry composition and potential gaseous emissions. A wide variability was found both in feed and slurry composition. Mediterranean farms had a higher pH (p<0.001) and ash (p=0.02) concentration than those located at the Centre of Spain. Also, type of farm affected ether extract content of the slurry (p=0.02), with highest values obtained for the youngest animal facilities. Results suggested a buffer effect of dietary fibre on slurry pH and a direct relationship (p<0.05) with fibre constituents of manure. Dietary protein content did not affect slurry nitrogen content but decreased (p=0.003) total and volatile solids concentration. Prediction models of potential NH3 emissions (R2=0.89) and CH4 yield (R2=0.61) were obtained from slurry composition. Predictions from NIRS showed a high accuracy for most slurry constituents (R2>0.90) and similar accuracy of prediction of potential NH3 and CH4 emissions (R2=0.84 and 0.68, respectively) to models using slurry characteristics, which can be of interest to estimate emissions from commercial farms and establish mitigation strategies or optimize biogas production. (Author)

  10. 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.

  11. Bentonite erosion. Laboratory studies

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Mats (Div. of Nuclear Chemistry, Royal Inst. of Technology, Stockholm (Sweden), School of Chemical Science and Engineering)

    2009-11-15

    This report covers the laboratory studies that have been performed at Nuclear Chemistry, KTH in the project 'Bentonite Erosion'. Many of the experiments in this report were performed to support the work of the modelling group and were often relatively simple. One of the experiment series was performed to see the impact of gravity and concentration of mono- and di-valent cations. A clay suspension was prepared in a test tube. A net was placed in contact with the suspension, the test tube was filled with solutions of different concentrations and the system was left overnight to settle. The tube was then turned upside down and the behaviour was visually observed. Either the clay suspension fell through the net or stayed on top. By using this method surprisingly sharp determinations of the Critical Coagulation (Flocculation) Concentration (CCC/CFC) could be made. The CCC/CFC of Ca2+ was for sodium montmorillonite determined to be between 1 and 2 mM. An artificial fracture was manufactured in order to simulate the real case scenario. The set-up was two Plexiglas slabs separated by 1 mm thick spacers with a bentonite container at one side of the fracture. Water was pumped with a very low flow rate perpendicular to bentonite container and the water exiting the fracture was sampled and analyzed for colloid content. The bentonite used was treated in different ways. In the first experiment a relatively montmorillonite rich clay was used while in the second bentonite where only the readily soluble minerals had been removed was used. Since Plexiglas was used it was possible to visually observe the bentonite dispersing into the fracture. After the compacted bentonite (1,000 kg/m3) had been water saturated the clay had expanded some 12 mm out into the fracture. As the experiment progressed the clay expanded more out into the fracture and seemed to fractionate in two different phases with less material in the outmost phase. A dark rim which was later analyzed to contain

  12. Bentonite erosion - Laboratory studies

    International Nuclear Information System (INIS)

    Jansson, Mats

    2010-01-01

    Document available in extended abstract form only. Bentonite clay is proposed as buffer material in the KBS-3 concept of storing spent nuclear fuel. Since the clay is plastic it will protect the canisters containing the spent fuel from movements in the rock. Furthermore, the clay will expand when taking up water, become very compact and hence limit the transport of solutes to and from the canister to only diffusion. The chemical stability of the bentonite barrier is of vital importance. If much material would be lost the barrier will lose its functions. As a side effect, lots of colloids will be released which may facilitate radionuclide transport in case of a breach in the canister. There are scenarios where during an ice age fresh melt water may penetrate down to repository depths with relatively high flow rates and not mix with older waters of high salinity. Under such conditions bentonite colloids will be more stable and there is a possibility that the bentonite buffer would start to disperse and bentonite colloids be carried away by the passing water. This work is a part of a larger project called Bentonite Erosion, initiated and supported by SKB. In this work several minor experiments have been performed in order to investigate the influence of for instance di-valent cations, gravity, etc. on the dispersion behaviour of bentonite and/or montmorillonite. A bigger experiment where the real situation was simulated using an artificial fracture was conducted. Two Plexiglas slabs were placed on top of each other, separated by plastic spacers. Bentonite was placed in a container in contact with a fracture. The bentonite was water saturated before deionized water was pumped through the fracture. The evolution of the bentonite profile in the fracture was followed visually. The eluate was collected in five different slots at the outlet side and analyzed for colloid concentration employing Photon Correlation Spectroscopy (PCS) and a Single Particle Counter (SPC). Some

  13. Soil erosion in Slovene Istria

    Directory of Open Access Journals (Sweden)

    Matjaž Mikoš

    2009-12-01

    Full Text Available From the end of nineties of the 20th century, intense hydrologic and geomorphologic research is taking place in the Slovene Istria. As a part of this research also studies on soil erosion were undertaken in the period from 2005 to 2008. The field measurements were under taken onclosed 1m2 large erosion plots under three different land uses (on bare soils in an olive grove, on an overgrown meadow, in a forest, placed south of the Marezige village in the Rokava River basin.We show weekly measurements of surface erosion (interrill erosion for the period of 13 months (the end of March 2005 – the end of April 2006, as well as monthly and seasonal averages together with selected linear statistical correlations between soil erosion and weather parameters.From May 2005 to April 2006 the interrill erosion on bare soils in an olive grove with an inclination of 5.5° amounted to 9013 g/m2 (90 t/ha that corresponds to surface lowering rate of 8.5 mm/yr; on an overgrown meadow with an inclination of 9.4° it amounted to 168 g/m2 (1,68 t/ha that corresponds to surface lowering rate of 0.16 mm//yr; and in a forest with an inclination of 7.8° it amounted to 391 g/m2 (3,91 t/ha and in a forest with an inclination of 21.4° it amounted to 415 g/m2 (4,15 t/ha, respectively, that corresponds to surface lowering rate of 0.4 mm/yr.

  14. An Enhanced Factor Analysis of Performance Degradation Assessment on Slurry Pump Impellers

    Directory of Open Access Journals (Sweden)

    Shilong Sun

    2017-01-01

    Full Text Available Slurry pumps, such as oil sand pumps, are widely used in industry to convert electrical energy to slurry potential and kinetic energy. Because of adverse working conditions, slurry pump impellers are prone to suffer wear, which may result in slurry pump breakdowns. To prevent any unexpected breakdowns, slurry pump impeller performance degradation assessment should be immediately conducted to monitor the current health condition and to ensure the safety and reliability of slurry pumps. In this paper, to provide an alternative to the impeller health indicator, an enhanced factor analysis based impeller indicator (EFABII is proposed. Firstly, a low-pass filter is employed to improve the signal to noise ratios of slurry pump vibration signals. Secondly, redundant statistical features are extracted from the filtered vibration signals. To reduce the redundancy of the statistic features, the enhanced factor analysis is performed to generate new statistical features. Moreover, the statistic features can be automatically grouped and developed a new indicator called EFABII. Data collected from industrial oil sand pumps are used to validate the effectiveness of the proposed method. The results show that the proposed method is able to track the current health condition of slurry pump impellers.

  15. On-farm impact of cattle slurry manure management on biological soil quality

    NARCIS (Netherlands)

    Goede, de R.G.M.; Brussaard, L.; Akkermans, A.D.L.

    2003-01-01

    The effects of dairy cattle slurry management on soil biota, soil respiration and nitrogen (N) mineralization were evaluated in a farm trial across 12 farms and a field experiment on 2 farms located in a dairy farming area in the north of the Netherlands. The slurry management consisted of slit

  16. The impact of slurry application technique on nitrous oxide emission from agricultural soils

    NARCIS (Netherlands)

    Velthof, G.L.; Mosquera, J.

    2011-01-01

    Direct nitrous oxide (N2O) emissions from fertilized soils are generally estimated using emission factors. However, the emission factors for N2O emission of applied slurry are not well quantified. The effect of slurry application technique on N2O emission was quantified in field experiments in the

  17. 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.

  18. 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)

  19. The influence of adsorption capacity on enhanced gas absorption in activated carbon slurries

    NARCIS (Netherlands)

    Holstvoogd, R.D.; van Swaaij, Willibrordus Petrus Maria

    1990-01-01

    The enhanced absorption of gases in aqueous activated carbbon slurries of fine particles is studied with a non-steady-state absorption model, taking into account the finite adsorption capacity of the carbon particles. It has been found that, for the different gas/activated carbon slurry systems

  20. Upland and wetland vegetation establishment on coal slurry in northern Missouri

    International Nuclear Information System (INIS)

    Skeel, V.A.; Nawrot, J.R.

    1998-01-01

    Since the Cooperative Wildlife Research Laboratory's (CWRL) Mined Land Reclamation Program's first establishment of a wetland on slurry in 1976, industry, state, and federal agency interest in reclamation alternatives for inactive slurry has increased. CWRL has been involved in pre-reclamation site characterization and monitoring for inactive slurry impoundments throughout Illinois, Indiana, Kansas, Kentucky, Missouri, and Washington. Geochemical site characterization of three slurry impoundments at the AECI Bee Veer Mine located near Macon, Missouri began in April 1990. A substrate sampling grid was established for all slurry impoundments with a centerline orientated parallel to the discharge to decant flow pattern. Surface (0--6 in.) and subsurface (30--36 in.) slurry samples were collected annually and analyzed for acid-base balance, immediate acidity macro- and micro-nutrients, potential phytotoxic metallic ions and salts, and texture. Water table elevations and water quality were monitored quarterly from shallow (≤12 ft.) piezometers. General reclamation plans included annual (3 years) incremental limestone amendments (35--50 tons/acre) and direct vegetation establishment. Cool and warm season grasses dominate vegetation cover in upland habitats (slurry cell RDA1) while wetland habitats (palustrine emergent seasonally-permanently inundated) have been established in slurry cells (RDA2 and RDA3). Isolated hot spots continue to be amended with limestone and supplemental vegetation establishment is scheduled

  1. Redistribution and persistence of microorganisms and steroid hormones after soil-injection of swine slurry

    DEFF Research Database (Denmark)

    Amin, Mostofa; Bech, Tina B.; Forslund, Anita

    2014-01-01

    Typhimurium Bacteriophage 28B (phage 28B), Escherichia coli, steroid hormones and other slurry components (water, volatile solids, chloride and mineral N) determined in and around the injection slit. The two experiments at Silstrup and Estrup differed with respect to slurry solid content (6.3 vs. 0...

  2. Development of ultra-lightweight slurries with high compressive strength for use in oil wells

    Energy Technology Data Exchange (ETDEWEB)

    Suzart, J. Walter P. [Halliburton Company, Houston, TX (United States); Farias, A.C. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Ribeiro, Danilo; Fernandes, Thiago; Santos, Reened [Halliburton Energy Services Aberdeen, Scotland (United Kingdom)

    2008-07-01

    Formations with low fracture gradients or depleted reservoirs often lead to difficult oil well cementing operations. Commonly employed cement slurries (14.0 to 15.8 lb/gal), generate an equivalent circulating density (ECD) higher than the fracture gradient and ultimately lead to formation damage, lost circulation and a decreased top of cement. Given the high price of oil, companies are investing in those and other wells that are difficult to explore. Naturally, lightweight cement slurries are used to reduce the ECD (10.0 to 14.0 lb/gal), using additives to trap water and stabilize the slurry. However, when the density reaches 11.0 lb/gal, the increase in water content may cause a change in characteristics. The focus of this study is extreme cases where it is necessary to employ ultra-lightweight cement slurries (5.5 to 10.0 lb/gal). Foamed slurries have been widely used, and the objective is to set an alternative by developing cement slurries containing uncompressible microspheres, aiming for a density of 7.5 lb/gal as well as high compressive strength. Another benefit in contrast to preparing foamed cement slurries is that there is no requirement for special equipment in the field. Routine laboratory tests such as fluid-loss control, sedimentation, thickening time, free water, compressive strength, and rheology (at room and high temperatures) were performed. Thus, it was concluded that the proposed cement slurries can be used in oil wells. (author)

  3. Effects of slurry application methods on soil faunal communities in permanent grassland

    NARCIS (Netherlands)

    Vliet, van P.C.J.; Goede, de R.G.M.

    2006-01-01

    We studied the effects of two slurry manure application methods, broadcasting manure slurry (MB) and manure slit injection (SMI), on soil faunal communities 1 week and 4 or 5 weeks after application in the spring of 2002 and the summer of 2003. No effect on total numbers of Enchytraeidae and

  4. ABSORPTION OF GASES INTO ACTIVATED CARBON WATER SLURRIES IN A STIRRED CELL

    NARCIS (Netherlands)

    TINGE, JT; DRINKENBURG, AAH

    A surface-aerated stirred cell with a flat liquid surface was used to investigate the absorption of propane and ethene gas into slurries of activated carbon and water. Slurries with a solids concentration up to 4% by weight and particle diameters up to 565-mu-m were used. The experimental mass

  5. Anaerobic digestion of pig manure fibres from commercial pig slurry separation units

    DEFF Research Database (Denmark)

    Thygesen, Ole; Triolo, Jin M.; Sommer, Sven G.

    2014-01-01

    and screw press on average produced approximately 220l [CH4]kg-1 [VS]. Initial methane production can be described using a first-order kinetic model. The average rate constant for manure fibres was 0.030d-1 and for pig slurry 0.071d-1, showing that pig slurry is digested much faster than manure fibres....

  6. The fate of sulfate in acidified pig slurry during storage and following application to cropped soil

    DEFF Research Database (Denmark)

    Eriksen, Jørgen; Sørensen, Peter; Elsgaard, Lars

    2008-01-01

    -available sulfate form. Microbial sulfate reduction during storage of acidified pig slurry was limited, presumably due to initial pH effects and a limitation in the availability of easily degradable organic matter. Sulfide accumulation was observed during storage but the sulfide levels in acidified slurry did...

  7. EFFECTS OF SLOPE SHAPES ON SOIL EROSION

    Directory of Open Access Journals (Sweden)

    Hüseyin ŞENSOY, Şahin PALTA

    2009-01-01

    Full Text Available Water is one of the most important erosive forces. A great number of factors also play a role in erosion process and slope characteristic is also one of them. The steepness and length of the slope are important factors for runoff and soil erosion. Another slope factor that has an effect on erosion is the shape of the slope. Generally, different erosion and runoff characteristics exist in different slopes which can be classified as uniform, concave, convex and complex shape. In this study, the effects of slope shape on erosion are stated and emphasized by taking similar researches into consideration.

  8. KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYNTHESIS

    Energy Technology Data Exchange (ETDEWEB)

    Dragomir B. Bukur; Gilbert F. Froment; Lech Nowicki; Jiang Wang; Wen-Ping Ma

    2003-09-29

    This report covers the first year of this three-year research grant under the University Coal Research program. The overall objective of this project is to develop a comprehensive kinetic model for slurry phase Fischer-Tropsch synthesis on iron catalysts. This model will be validated with experimental data obtained in a stirred tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict concentrations of all reactants and major product species (H{sup 2}O, CO{sub 2}, linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the reporting period we have completed one STSR test with precipitated iron catalyst obtained from Ruhrchemie AG (Oberhausen-Holten, Germany). This catalyst was initially in commercial fixed bed reactors at Sasol in South Africa. The catalyst was tested at 13 different sets of process conditions, and had experienced a moderate deactivation during the first 500 h of testing (decrease in conversion from 56% to 50% at baseline process conditions). The second STSR test has been initiated and after 270 h on stream, the catalyst was tested at 6 different sets of process conditions.

  9. Microbial examination of anaerobic sludge adaptation to animal slurry.

    Science.gov (United States)

    Moset, V; Cerisuelo, A; Ferrer, P; Jimenez, A; Bertolini, E; Cambra-López, M

    2014-01-01

    The objective of this study was to evaluate changes in the microbial population of anaerobic sludge digesters during the adaptation to pig slurry (PS) using quantitative real-time polymerase chain reaction (qPCR) and qualitative scanning electron microscopy (SEM). Additionally, the relationship between microbial parameters and sludge physicochemical composition and methane yield was examined. Results showed that the addition of PS to an unadapted thermophilic anaerobic digester caused an increase in volatile fatty acids (VFA) concentration, a decrease in removal efficiency and CH4 yield. Additionally, increases in total bacteria and total archaea were observed using qPCR. Scanning electron micrographs provided a general overview of the sludge's cell morphology, morphological diversity and degree of organic matter degradation. A change in microbial morphotypes from homogeneous cell morphologies to a higher morphological diversity, similar to that observed in PS, was observed with the addition of PS by SEM. Therefore, the combination of qPCR and SEM allowed expanding the knowledge about the microbial adaptation to animal slurry in thermophilic anaerobic digesters.

  10. Slurry-phase biodegradation of weathered oily sludge waste.

    Science.gov (United States)

    Machín-Ramírez, C; Okoh, A I; Morales, D; Mayolo-Deloisa, K; Quintero, R; Trejo-Hernández, M R

    2008-01-01

    We assessed the biodegradation of a typical oily sludge waste (PB401) in Mexico using several regimes of indigenous microbial consortium and relevant bioremediation strategies in slurry-phase system. Abiotic loss of total petroleum hydrocarbons (TPH) in the PB401 was insignificant, and degradation rates under the various treatment conditions ranged between 666.9 and 2168.7 mg kg(-1) day(-1) over a 15 days reaction period, while viable cell count peaked at between log(10)5.7 and log(10)7.4 cfu g(-1). Biostimulation with a commercial fertilizer resulted in 24% biodegradation of the TPH in the oily waste and a corresponding peak cell density of log(10)7.4 cfu g(-1). Addition of non-indigenous adapted consortium did not appear to enhance the removal of TPH from the oily waste. It would appear that the complexities of the components of the alkylaromatic fraction of the waste limited biodegradation rate even in a slurry system.

  11. Rheology of corn stover slurries during fermentation to ethanol

    Science.gov (United States)

    Ghosh, Sanchari; Epps, Brenden; Lynd, Lee

    2017-11-01

    In typical processes that convert cellulosic biomass into ethanol fuel, solubilization of the biomass is carried out by saccharolytic enzymes; however, these enzymes require an expensive pretreatment step to make the biomass accessible for solubilization (and subsequent fermentation). We have proposed a potentially-less-expensive approach using the bacterium Clostridium thermocellum, which can initiate fermentation without pretreatment. Moreover, we have proposed a ``cotreatment'' process, in which fermentation and mechanical milling occur alternately so as to achieve the highest ethanol yield for the least milling energy input. In order to inform the energetic requirements of cotreatment, we experimentally characterized the rheological properties of corn stover slurries at various stages of fermentation. Results show that a corn stover slurry is a yield stress fluid, with shear thinning behavior well described by a power law model. Viscosity decreases dramatically upon fermentation, controlling for variables such as solids concentration and particle size distribution. To the authors' knowledge, this is the first study to characterize the changes in the physical properties of biomass during fermentation by a thermophilic bacterium.

  12. Recycling Pig Slurry Solid Fraction Compost as a Sound Absorber

    Directory of Open Access Journals (Sweden)

    Niccolò Pampuro

    2018-01-01

    Full Text Available The aim of this investigation was to determine the physical and acoustical properties of compacts made from composted pig slurry solid fraction (SF in order to assess the potential to recycle this agricultural waste as a sound absorber. The compacts were obtained by compression. The physical parameters investigated were bulk density, durability, and particle size distribution. The acoustical features of the compacts were studied with an impedance tube device in order to verify the acoustic absorption coefficient. Two composts were prepared: pig SF compost without a bulking agent (SSFC and pig SF compost with wood chips as a bulking agent (WCC. The study’s results indicated that compost particles dimension played a key role in the physical and acoustical properties of the compacts: the smaller the particles, the higher the physical and acoustical properties of the compacts. The densification process increased the bulk density of the investigated composts up to 690 kg m−3 for SSFC and 660 kg m−3 for WWC, with, respectively, medium (77.9% and low (66.5% durability. The addition of woody bulking agent significantly reduced the absorption coefficient: the best results, in terms of potential use as a sound absorber, were observed for compacts made from composted pig slurry solid fraction without the addition of wood chips.

  13. Metals attenuation in minerally-enhanced slurry walls

    International Nuclear Information System (INIS)

    Evans, J.C.; Prince, M.J.; Adams, T.L.

    1997-01-01

    In current practice, a soil-bentonite slurry trench cutoff wall is a mixture of water, soil, and bentonite that is designed to serve as a passive barrier to ground water and contaminant transport. This study evaluated the transformation of a passive slurry trench cutoff wall barrier to an active barrier system. Conventional soil-bentonite vertical barriers presently serve as passive barriers to contaminated ground water. An active barrier will not only fulfill the functions of the present passive barrier system, but also retard contaminant transport by adsorptive processes. Attapulgite, Na-chabazite, and Ca-chabazite were added to open-quotes activateclose quotes the conventional soil-bentonite backfill. Batch extraction tests were performed to determine the partitioning coefficients of cadmium and zinc between the liquid and solid phase when in contact with the backfill mixes. Batch extraction and mathematical modeling results demonstrate the ability of an active barrier to retard the transport of cadmium and zinc. The reactivity of the soil-bentonite vertical barrier depends heavily on the inorganic being adsorbed. The reactivity of the barrier also depends on the adsorptive capabilities of the clay minerals added to the conventional soil-bentonite vertical barrier. The results of laboratory studies suggest that passive barrier systems can be transformed to active systems. Further, the data suggests that although conventional soil-bentonite vertical barriers are presently designed as passive barriers, they already have adsorptive capacity associated with active barriers

  14. KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYNTHESIS

    International Nuclear Information System (INIS)

    Dragomir B. Bukur; Gilbert F. Froment; Lech Nowicki; Jiang Wang; Wen-Ping Ma

    2003-01-01

    This report covers the first year of this three-year research grant under the University Coal Research program. The overall objective of this project is to develop a comprehensive kinetic model for slurry phase Fischer-Tropsch synthesis on iron catalysts. This model will be validated with experimental data obtained in a stirred tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict concentrations of all reactants and major product species (H 2 O, CO 2 , linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the reporting period we have completed one STSR test with precipitated iron catalyst obtained from Ruhrchemie AG (Oberhausen-Holten, Germany). This catalyst was initially in commercial fixed bed reactors at Sasol in South Africa. The catalyst was tested at 13 different sets of process conditions, and had experienced a moderate deactivation during the first 500 h of testing (decrease in conversion from 56% to 50% at baseline process conditions). The second STSR test has been initiated and after 270 h on stream, the catalyst was tested at 6 different sets of process conditions

  15. KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYNTHESIS

    International Nuclear Information System (INIS)

    Dragomir B. Bukur

    2004-01-01

    This report covers the second year of this three-year research grant under the University Coal Research program. The overall objective of this project is to develop a comprehensive kinetic model for slurry phase Fischer-Tropsch synthesis on iron catalysts. This model will be validated with experimental data obtained in a stirred tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict concentrations of all reactants and major product species (H 2 O, CO 2 , linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the second year of the project we completed the STSR test SB-26203 (275-343 h on stream), which was initiated during the first year of the project, and another STSR test (SB-28603 lasting 341 h). Since the inception of the project we completed 3 STSR tests, and evaluated catalyst under 25 different sets of process conditions. A precipitated iron catalyst obtained from Ruhrchemie AG (Oberhausen-Holten, Germany) was used in all tests. This catalyst was used initially in commercial fixed bed reactors at Sasol in South Africa. Also, during the second year we performed a qualitative analysis of experimental data from all three STSR tests. Effects of process conditions (reaction temperature, pressure, feed composition and gas space velocity) on water-gas-shift (WGS) activity and hydrocarbon product distribution have been determined

  16. Aerosol entrainment from a sparged non-Newtonian slurry.

    Science.gov (United States)

    Fritz, Brad G

    2006-08-01

    Previous bench-scale experiments have provided data necessary for the development of empirical models that describe aerosol entrainment from bubble bursting. However, previous work has not been extended to non-Newtonian liquid slurries. Design of a waste treatment plant on the Hanford Site in Washington required an evaluation of the applicability of these models outside of their intended range. For this evaluation, aerosol measurements were conducted above an air-sparged mixing tank filled with simulated waste slurry possessing Bingham plastic rheological properties. Three aerosol-size fractions were measured at three sampling heights and for three different sparging rates. The measured entrainment was compared with entrainment models. One model developed based on bench-scale air-water experiments agreed well with measured entrainment. Another model did not agree well with the measured entrainment. It appeared that the source of discrepancy between measured and modeled entrainment stemmed from application beyond the range of data used to develop the model. A possible separation in entrainment coefficients between air-water and steam-water systems was identified. A third entrainment model was adapted to match experimental conditions and fit a posteri to the experimental data, resulting in a modified version that resulted in estimated entrainment rates similar to the first model.

  17. An Experimental Study of Portland Cement and Superfine Cement Slurry Grouting in Loose Sand and Sandy Soil

    OpenAIRE

    Weijing Yao; Jianyong Pang; Yushan Liu

    2018-01-01

    Grouting technology is widely applied in the fields of geotechnical engineering in infrastructure. Loose sand and sandy soil are common poor soils in tunnel and foundation treatments. It is necessary to use superfine cement slurry grouting in the micro-cracks of soil. The different effectiveness of Portland cement slurry and superfine cement slurry in sandy soil by the laboratory grouting experiment method were presented in this paper. The grouting situations of superfine cement slurry inject...

  18. Experimental investigation of combustion of biomass slurry in an oil fired furnace

    Energy Technology Data Exchange (ETDEWEB)

    Prakash, S.V. [Mechanical Dept., M.S. Ramaiah Inst. of Tech., Bangalore (India); Shankapal, S.R. [M.S. Ramaiah School of Advanced Studies, Bangalore (India)

    2008-07-01

    An experimental investigation of combustion of biomass slurry in an oil fired furnace was carried out using pulverized coconut shell (CSP), LDO and water. The effect of equivalence ratio on the slurry composition, calorific value and the effect of exhaust gas percentage are presented. The calorific value of the biomass slurry increases with equivalence ratio initially, attains a peak value and then decreases with the increase in equivalence ratio. It is also observed that with the increase in composition of biomass slurry, the cost of the fuel and the percentage emission of CO decreases. It was found that CSP up to a blend of 20% was more convenient to be used as a slurry fuel in the furnace. (orig.)

  19. Spread of Hepatitis E virus from pig slurry to the water environment

    DEFF Research Database (Denmark)

    Krog, Jesper Schak; Forslund, Anita; Breum, Solvej Østergaard

    Objectives: Spread of pig slurry as an organic fertilizer is commonly used in Danish agriculture. The slurry is spread untreated so pathogens able to survive in slurry tanks will be widely distributed in the environment. The objective of this study was to examine if hepatitis E virus (HEV), which......), and hence could present a risk for virus transmission to wildlife and shellfish. We tested the presence of HEV in water drained from a test field where slurry from a Danish pig farm had been applied and in mussels from different regions in Denmark with fields in close proximity. Methods: Slurry from......). In addition, samples of water collected from wells located along the field and groundwater. Archived mussels from different regions in Denmark were included in the study. Virus was concentrated from water using Poly Ethylene Glycol precipitation and virus from the digestive tissue of the mussels was extracted...

  20. Technical Report on NETL's Non Newtonian Multiphase Slurry Workshop: A path forward to understanding non-Newtonian multiphase slurry flows

    Energy Technology Data Exchange (ETDEWEB)

    Guenther, Chris [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Garg, Rahul [National Energy Technology Lab. (NETL), Morgantown, WV (United States)

    2013-08-19

    The Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) sponsored a workshop on non-Newtonian multiphase slurry at NETL’s Morgantown campus August 19 and 20, 2013. The objective of this special two-day meeting of 20-30 invited experts from industry, National Labs and academia was to identify and address technical issues associated with handling non-Newtonian multiphase slurries across various facilities managed by DOE. Particular emphasis during this workshop was placed on applications managed by the Office of Environmental Management (EM). The workshop was preceded by two webinars wherein personnel from ORP and NETL provided background information on the Hanford WTP project and discussed the critical design challenges facing this project. In non-Newtonian fluids, viscosity is not constant and exhibits a complex dependence on applied shear stress or deformation. Many applications under EM’s tank farm mission involve non-Newtonian slurries that are multiphase in nature; tank farm storage and handling, slurry transport, and mixing all involve multiphase flow dynamics, which require an improved understanding of the mechanisms responsible for rheological changes in non-Newtonian multiphase slurries (NNMS). To discuss the issues in predicting the behavior of NNMS, the workshop focused on two topic areas: (1) State-of-the-art in non-Newtonian Multiphase Slurry Flow, and (2) Scaling up with Confidence and Ensuring Safe and Reliable Long-Term Operation.

  1. Design Mixers to Minimize Effects of Erosion and Corrosion Erosion

    Directory of Open Access Journals (Sweden)

    Julian Fasano

    2012-01-01

    Full Text Available A thorough review of the major parameters that affect solid-liquid slurry wear on impellers and techniques for minimizing wear is presented. These major parameters include (i chemical environment, (ii hardness of solids, (iii density of solids, (iv percent solids, (v shape of solids, (vi fluid regime (turbulent, transitional, or laminar, (vii hardness of the mixer's wetted parts, (viii hydraulic efficiency of the impeller (kinetic energy dissipation rates near the impeller blades, (ix impact velocity, and (x impact frequency. Techniques for minimizing the wear on impellers cover the choice of impeller, size and speed of the impeller, alloy selection, and surface coating or coverings. An example is provided as well as an assessment of the approximate life improvement.

  2. The rheology of cryovolcanic slurries: Motivation and phenomenology of methanol-water slurries with implications for Titan

    Science.gov (United States)

    Zhong, Fang; Mitchell, Karl L.; Hays, Charles C.; Choukroun, Mathieu; Barmatz, Martin; Kargel, Jeffrey S.

    2009-08-01

    The Cassini spacecraft has revealed landforms on the surface of Titan suggested to be viscous cryovolcanic flows and possibly eruptive domes. In order to relate those surface features to the processes and chemistries that produced them, it is necessary to construct flow models, which rely on characterization of the rheological properties of the eruptants. This paper describes our initial exploratory attempts to understand the rheological characteristics of cryogenic slurries, using a 40% methanol-water mixture, as a precursor to more detailed experiments. We have devised a new automated cryogenic rotational viscometer system to more fully characterize cryovolcanic slurry rheologies. A series of measurements were performed, varying first temperature, and then strain rate, which revealed development of yield stress-like behaviors, shear-rate dependence, and thixotropic behavior, even at relatively low crystal fractions, not previously reported. At fixed shear rate our data are fit well by the Andrade equation, with the activation energy modified by a solid volume fraction. At fixed temperature, depending on shearing history, a Cross model could describe our data over a wide shear rate range. A Bingham plastic model appears to be a good constitutive model for the data measured at high shear rates when the shear was global. The yield stress like behavior implies that levee formation on cryolava flows is more likely than would be inferred from the previous studies, and may provide a partial explanation for features interpreted as steep-sided volcanic constructs on Titan.

  3. 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.

  4. Elevated temperature erosive wear of metallic materials

    International Nuclear Information System (INIS)

    Roy, Manish

    2006-01-01

    Solid particle erosion of metals and alloys at elevated temperature is governed by the nature of the interaction between erosion and oxidation, which, in turn, is determined by the thickness, pliability, morphology, adhesion characteristics and toughness of the oxide scale. The main objective of this paper is to critically review the present state of understanding of the elevated temperature erosion behaviour of metals and alloys. First of all, the erosion testing at elevated temperature is reviewed. This is followed by discussion of the essential features of elevated temperature erosion with special emphasis on microscopic observation, giving details of the erosion-oxidation (E-O) interaction mechanisms. The E-O interaction has been elaborated in the subsequent section. The E-O interaction includes E-O maps, analysis of transition criteria from one erosion mechanism to another mechanism and quantification of enhanced oxidation kinetics during erosion. Finally, the relevant areas for future studies are indicated. (topical review)

  5. Understanding Soil Erosion in Irrigated Agriculture

    OpenAIRE

    O' Schwankl, Lawrence J

    2006-01-01

    A soil's physical and chemical properties determine whether it is vulnerable to erosion, which can reduce soil quality and cause other problems besides. Learn the basics of identifying what type of erosion is affecting your land and what's causing it.

  6. Erosion of the first wall of Tokamaks

    International Nuclear Information System (INIS)

    Guseva, M.I.; Ionova, E.S.; Martynenko, Yu.V.

    1980-01-01

    An estimate of the rate of erosion of the wall due to sputtering and blistering requires knowledge of the fluxes and energies of the particles which go from the plasma to the wall, of the sputtering coefficients S, and of the erosion coefficients S* for blistering. The overall erosion coefficient is equal to the sum of the sputtering coefficient and the erosion coefficient for blistering. Here the T-20 Tokamak is examined as an example of a large-scale Tokamak. 18 refs

  7. Soil Erosion. LC Science Tracer Bullet.

    Science.gov (United States)

    Buydos, John F., Comp.

    Soil erosion is the detachment and movement of topsoil or soil material from the upper part of the soil profile. It may occur in the form of rill, gully, sheet, or wind erosion. Agents of erosion may be water, wind, glacial ice, agricultural implements, machinery, and animals. Soil conservation measures require a thorough understanding of the…

  8. Natural and anthropogenic rates of soil erosion

    Science.gov (United States)

    Regions of land that are brought into crop production from native vegetation typically undergo a period of soil erosion instability, and long term erosion rates are greater than for natural lands as long as the land continues being used for crop production. Average rates of soil erosion under natur...

  9. Soil erosion in humid regions: a review

    Science.gov (United States)

    Daniel J. Holz; Karl W.J. Williard; Pamela J. Edwards; Jon E. Schoonover

    2015-01-01

    Soil erosion has significant implications for land productivity and surface water quality, as sediment is the leading water pollutant worldwide. Here, erosion processes are defined. The dominant factors influencing soil erosion in humid areas are reviewed, with an emphasis on the roles of precipitation, soil moisture, soil porosity, slope steepness and length,...

  10. Erosion/corrosion concerns in feed preparation systems at the Defense Waste Processing Facility

    International Nuclear Information System (INIS)

    Gee, J.T.; Chandler, C.T.; Daugherty, W.L.; Imrich, K.J.; Jenkins, C.F.

    1997-01-01

    The Savannah River Site (SRS) has been operating a nuclear fuel cycle since the 1950's to produce nuclear materials in support of the national defense effort. The Department of Energy authorized the construction of the Defense Waste Processing Facility (DWPF) to immobilize the high level radioactive waste resulting from these processes as a durable borosilicate glass. The DWPF, after having undergone extensive testing, has been approved for operations and is currently immobilizing radioactive waste. To ensure reliability of the DWPF remote canyon processing equipment, a materials evaluation program was performed prior to radioactive operations to determine to what extent erosion/corrosion would impact design life of equipment. The program consisted of performing pre-service baseline inspections on critical equipment and follow-up inspections after completion of DWPF cold chemical demonstration runs. Non-destructive examination (NDE) techniques were used to assess erosion/corrosion as well as evaluation of corrosion coupon racks. These results were used to arrive at predicted equipment life for selected feed preparation equipment. It was concluded with the exception of the coil and agitator for the slurry mix evaporator (SME), which are exposed to erosive glass frit particles, all of the equipment should meet its design life

  11. Modeling the fluid/soil interface erosion in the Hole Erosion Test

    Directory of Open Access Journals (Sweden)

    Kissi B.

    2012-07-01

    Full Text Available Soil erosion is a complex phenomenon which yields at its final stage to insidious fluid leakages under the hydraulic infrastructures known as piping and which are the main cause of their rupture. The Hole Erosion Test is commonly used to quantify the rate of piping erosion. In this work, The Hole Erosion Test is modelled by using Fluent software package. The aim is to predict the erosion rate of soil during the hole erosion test. The renormalization group theory – based k–ε turbulence model equations are used. This modelling makes it possible describing the effect of the clay concentration in flowing water on erosion. Unlike the usual one dimensional models, the proposed modelling shows that erosion is not uniform erosion along the hole length. In particular, the concentration of clay is found to increase noticeably the erosion rate.

  12. Abrasive slurry jet cutting model based on fuzzy relations

    Science.gov (United States)

    Qiang, C. H.; Guo, C. W.

    2017-12-01

    The cutting process of pre-mixed abrasive slurry or suspension jet (ASJ) is a complex process affected by many factors, and there is a highly nonlinear relationship between the cutting parameters and cutting quality. In this paper, guided by fuzzy theory, the fuzzy cutting model of ASJ was developed. In the modeling of surface roughness, the upper surface roughness prediction model and the lower surface roughness prediction model were established respectively. The adaptive fuzzy inference system combines the learning mechanism of neural networks and the linguistic reasoning ability of the fuzzy system, membership functions, and fuzzy rules are obtained by adaptive adjustment. Therefore, the modeling process is fast and effective. In this paper, the ANFIS module of MATLAB fuzzy logic toolbox was used to establish the fuzzy cutting model of ASJ, which is found to be quite instrumental to ASJ cutting applications.

  13. Double shell slurry low-temperature corrosion tests

    International Nuclear Information System (INIS)

    Divine, J.R.; Bowen, W.M.; McPartland, S.A.; Elmore, R.P.; Engel, D.W.

    1983-09-01

    A series of year-long tests have been completed on potential double shell slurry (DSS) compositions at temperatures up to 100 0 C. These tests have sought data on uniform corrosion, pitting, and stress-corrosion cracking. No indication of the latter two types of corrosion were observed within the test matrix. Corrosion rates after four months were generally below the 1 mpy (25 μm/y) design limit. By the end of twelve months all results were below this limit and, except for very concentrated mixtures, all were below 0.5 mpy. Prediction equations were generated from a model fitted to the data. The equations provide a rapid means of estimating the corrosion rate for proposed DSS compositions

  14. Formation and filtration of flocs from coal slurries

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B K

    1977-06-01

    The size and size distribution of flocs are greatly influenced by the type and concentration of the flocculant coal and dirt particles behave differently in this respect. The pH and the concentration of electrolytes also influence flocculation, by changing both the surface properties of the solid material and the effectiveness of the flocculant. The relationship between the sedimentation time and the filtration rate depends on the concentration and type of flocculant. Optimum pH values for various conditions are tabulated. When an anion-active flocculant is added to a coal-dirt mixture in an alkaline medium, selective flocculation occurs; this can be used to improve the separation of slurries.

  15. An integrated approach to route selection in slurry pipeline design

    Energy Technology Data Exchange (ETDEWEB)

    Betinol, Roy G.; Altmann, Nara [Brass Chile S.A., Santiago (Chile)

    2009-12-19

    The pressure to get engineering projects done and constructed as fast as possible in order to take advantage of the high prices in metals and petrochemicals has been driving companies to skip the conceptual phase and go straight into basic engineering with cost estimates in the level of 15% accuracy. By-passing early engineering and demanding higher cost estimating accuracy is a contradiction. In most cases, savings made on capital investment is much higher had money been spent in conceptual studies which allow for the optimal solution to be found. This paper reviews one of the key aspects in conceptual engineering of slurry pipeline designs: route selection. This activity is often overlooked, causing capital cost and operating difficulties to rise unnecessarily. This paper describes and gives example on how an integrated client/engineering company's approach to route selection can produce significant savings in pipeline construction and operating costs. (author)

  16. The Arctic Coastal Erosion Problem

    Energy Technology Data Exchange (ETDEWEB)

    Frederick, Jennifer M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Thomas, Matthew Anthony [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bull, Diana L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Craig A. [Integral Consulting Inc., San Francisco, CA (United States); Roberts, Jesse D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-09-01

    Permafrost-dominated coastlines in the Arctic are rapidly disappearing. Arctic coastal erosion rates in the United States have doubled since the middle of the twentieth century and appear to be accelerating. Positive erosion trends have been observed for highly-variable geomorphic conditions across the entire Arctic, suggesting a major (human-timescale) shift in coastal landscape evolution. Unfortunately, irreversible coastal land loss in this region poses a threat to native, industrial, scientific, and military communities. The Arctic coastline is vast, spanning more than 100,000 km across eight nations, ten percent of which is overseen by the United States. Much of area is inaccessible by all-season roads. People and infrastructure, therefore, are commonly located near the coast. The impact of the Arctic coastal erosion problem is widespread. Homes are being lost. Residents are being dispersed and their villages relocated. Shoreline fuel storage and delivery systems are at greater risk. The U.S. Department of Energy (DOE) and Sandia National Laboratories (SNL) operate research facilities along some of the most rapidly eroding sections of coast in the world. The U.S. Department of Defense (DOD) is struggling to fortify coastal radar sites, operated to ensure national sovereignty in the air, against the erosion problem. Rapid alterations to the Arctic coastline are facilitated by oceanographic and geomorphic perturbations associated with climate change. Sea ice extent is declining, sea level is rising, sea water temperature is increasing, and permafrost state is changing. The polar orientation of the Arctic exacerbates the magnitude and rate of the environmental forcings that facilitate coastal land area loss. The fundamental mechanics of these processes are understood; their non-linear combination poses an extreme hazard. Tools to accurately predict Arctic coastal erosion do not exist. To obtain an accurate predictive model, a coupling of the influences of

  17. The role of heterotrophic microorganism Galactomyces sp. Z3 in improving pig slurry bioleaching.

    Science.gov (United States)

    Zhou, Jun; Zheng, Guanyu; Zhou, Lixiang; Liu, Fenwu; Zheng, Chaocheng; Cui, Chunhong

    2013-01-01

    The feasibility of removing heavy metals and eliminating pathogens from pig slurry through bioleaching involving the fungus Galactomyces sp. Z3 and two acidophilic thiobacillus (A. ferrooxidans LX5 and A. thiooxidans TS6) was investigated. It was found that the isolated pig slurry dissolved organic matter (DOM) degrader Z3 was identified as Galactomyces sp. Z3, which could grow well at pH 2.5-7 and degrade pig slurry DOM from 1973 to 942 mg/l within 48 h. During the successive multi-batch bioleaching systems, the co-inoculation of pig slurry degrader Galactomyces sp. Z3 and the two Acidithiobacillus species could improve pig slurry bioleaching efficiency compared to the single system without Galactomyces sp. Z3. The removal efficiency of Zn and Cu exceeded 94% and 85%, respectively. In addition, the elimination efficiencies of pathogens, including both total coliform and faecal coliform counts, exceeded 99% after bioleaching treatment. However, the counts of Galactomyces sp. Z3 decreased with the fall of pH and did not restore to the initial level during successive multi-batch bioleaching systems, and it is necessary to re-inoculate Galactomyces sp. Z3 cells into the bioleaching system to maintain its role in degrading pig slurry DOM. Therefore, a bioleaching technique involving both Galactomyces sp. Z3 and Acidithiobacillus species is an efficient method for removing heavy metals and eliminating pathogens from pig slurry.

  18. 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).

  19. Coal waste slurries as a fuel for integrated gasification combined cycle plants

    Directory of Open Access Journals (Sweden)

    Lutynski Marcin A.

    2016-01-01

    Full Text Available The article summarizes recent development in integrated gasification combined cycle technology and lists existing and planned IGCC plants. A brief outlook on the IGCC gasification technology is given with focus on entrained-flow gasifiers where the low-quality coal waste slurry fuel can be used. Desired properties of coal and ash for entrained-flow gasifiers are listed. The coal waste slurries, which were deposited at impoundments in Upper Silesian Coal Basin, were considered as a direct feed for such gasifiers. The average ash content, moisture content and lower heating value were analysed and presented as an average values. Entrained-flow commercial gasifiers can be considered as suitable for the coal slurry feed, however the ash content of coal slurries deposited in impoundments is too high for the direct use as the feed for the gasifiers. The moisture content of slurries calculated on as received basis meets the requirements of entrained-flow slurry feed gasifiers. The content of fines is relatively high which allow to use the slurries in entrained-flow gasifiers.

  20. 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

  1. Performance Study of Graphite Anode Slurry in Lithium-ion Flow Battery by Ball Milling

    Directory of Open Access Journals (Sweden)

    FENG Cai-mei

    2018-02-01

    Full Text Available Graphite anode slurry of lithium-ion flow battery was prepared by the method of ball milling. The morphology, conductivity, specific capacity and cycle performance of graphite anode slurry were studied. Results show that the addition of conductive carbon material can improve the suspension stability of the electrode slurry; the ball milling process can not only improve the suspension stability but also reduce the resistivity of the mixed powders of graphite and conductive carbon materials, the ball milling effect is satisfactory when the mass ratio of the balls and the solid particles is 5:1, but too high ratio of the milling ball and the solid materials can destroy the layer structure of the graphite and affect the stability of the slurry. Increasing the fraction of the graphite and conductive carbon materials can form stable electrical network structure in the slurry and improve the reversible capacity; at the premise of keeping the flowability of the electrode slurry, the reversible specific capacity can be more than 40mAh/g. The capacity loss of graphite anode slurry mainly occurs in the first charging-discharging process, as the increase of the cycles, the capacity loss rate decreases, the capacity goes stable after 5 cycles.

  2. 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

  3. 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

  4. Alcohol synthesis in a high-temperature slurry reactor

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, G.W.; Marquez, M.A.; McCutchen, M.S. [North Carolina State Univ., Raleigh, NC (United States)

    1995-12-31

    The overall objective of this contract is to develop improved process and catalyst technology for producing higher alcohols from synthesis gas or its derivatives. Recent research has been focused on developing a slurry reactor that can operate at temperatures up to about 400{degrees}C and on evaluating the so-called {open_quotes}high pressure{close_quotes} methanol synthesis catalyst using this reactor. A laboratory stirred autoclave reactor has been developed that is capable of operating at temperatures up to 400{degrees}C and pressures of at least 170 atm. The overhead system on the reactor is designed so that the temperature of the gas leaving the system can be closely controlled. An external liquid-level detector is installed on the gas/liquid separator and a pump is used to return condensed slurry liquid from the separator to the reactor. In order to ensure that gas/liquid mass transfer does not influence the observed reaction rate, it was necessary to feed the synthesis gas below the level of the agitator. The performance of a commercial {open_quotes}high pressure {close_quotes} methanol synthesis catalyst, the so-called {open_quotes}zinc chromite{close_quotes} catalyst, has been characterized over a range of temperature from 275 to 400{degrees}C, a range of pressure from 70 to 170 atm., a range of H{sub 2}/CO ratios from 0.5 to 2.0 and a range of space velocities from 2500 to 10,000 sL/kg.(catalyst),hr. Towards the lower end of the temperature range, methanol was the only significant product.

  5. Biological treatment of soils contaminated with hydrophobic organics using slurry- and solid-phase techniques

    Science.gov (United States)

    Cassidy, Daniel H.; Irvine, Robert L.

    1995-10-01

    Both slurry-phase and solid-phase bioremediation are effective ex situ soil decontamination methods. Slurrying is energy intensive relative to solid-phase treatment, but provides homogenization and uniform nutrient distribution. Limited contaminant bioavailability at concentrations above the required cleanup level reduces biodegradation rates and renders solid phase bioremediation more cost effective than complete treatment in a bio-slurry reactor. Slurrying followed by solid-phase bioremediation combines the advantages and minimizes the weaknesses of each treatment method when used alone. A biological treatment system consisting of slurrying followed by aeration in solid phase bioreactors was developed and tested in the laboratory using a silty clay loam contaminated with diesel fuel. The first set of experiments was designed to determine the impact of the water content and mixing time during slurrying on the rate an extent of contaminant removal in continuously aerated solid phase bioreactors. The second set of experiments compared the volatile and total diesel fuel removal in solid phase bioreactors using periodic and continuous aeration strategies. Results showed that slurrying for 1.5 hours at a water content less than saturation markedly increased the rate and extent of contaminant biodegradation in the solid phase bioreactors compared with soil having no slurry pretreatment. Slurrying the soil at or above its saturation moisture content resulted in lengthy dewatering times which prohibited aeration, thereby delaying the onset of biological treatment in the solid phase bioreactors. Results also showed that properly operated periodic aeration can provide less volatile contaminant removal and a grater fraction of biological contaminant removal than continuous aeration.

  6. Interim report: Study of benzene release from Savannah River in-tank precipitation process slurry simulant

    International Nuclear Information System (INIS)

    Rappe, K.G.; Gauglitz, P.A.

    1997-09-01

    At the Savannah River Site, the in-tank precipitation (ITP) process uses sodium tetraphenylborate (NaTPB) to precipitate radioactive cesium from alkaline wastes. During this process, potassium is also precipitated to form a 4-wt% KTPB/CsTPB slurry. Residual NaTPB decomposes to form benzene, which is retained by the waste slurry. The retained benzene is also readily released from the waste during subsequent waste processing. While the release of benzene certainly poses both flammability and toxicological safety concerns, the magnitude of the hazard depends on the rate of release. Currently, the mechanisms controlling the benzene release rates are not well understood, and predictive models for estimating benzene release rates are not available. The overall purpose of this study is to obtain quantitative measurements of benzene release rates from a series of ITP slurry stimulants. This information will become a basis for developing a quantitative mechanistic model of benzene release rates. The transient benzene release rate was measured from the surface of various ITP slurry (solution) samples mixed with benzene. The benzene release rate was determined by continuously purging the headspace of a sealed sample vessel with an inert gas (nitrogen) and analyzing that purged headspace vapor for benzene every 3 minutes. The following 75-mL samples were measured for release rates: KTPB slurry with 15,000 ppm freshly added benzene that was gently mixed with the slurry, KTPB slurry homogenized (energetically mixed) with 15,000 ppm and 5,000 ppm benzene, clear and filtered KTPB salt solution saturated with benzene (with and without a pure benzene layer on top of the solution), and a slurry sample from a large demonstration experiment (DEMO slurry) containing-benzene generated in situ

  7. Preventing erosion at pipeline crossings of watercourses

    International Nuclear Information System (INIS)

    Sawatsky, L.; Arnold, G.

    1997-01-01

    Watercourses are naturally vulnerable to erosion but the risk is particularly acute after sub-soil and armour materials have been disturbed by trenching and backfilling during construction. Various types of erosion (river scour, river bed, river channel bed and river bank ) and the progressive removal of pipeline cover resulting from erosion were discussed. Methods of estimating the risk of progressive erosion, river avulsions and beaver dam scour, and methods of mitigating erosion at pipeline crossings such as deep burial, proper siting, conventional armouring, and a combination of bank toe protection, and upper bank vegetation cover, were described

  8. Soil Erosion Threatens Food Production

    Directory of Open Access Journals (Sweden)

    Michael Burgess

    2013-08-01

    Full Text Available Since humans worldwide obtain more than 99.7% of their food (calories from the land and less than 0.3% from the oceans and aquatic ecosystems, preserving cropland and maintaining soil fertility should be of the highest importance to human welfare. Soil erosion is one of the most serious threats facing world food production. Each year about 10 million ha of cropland are lost due to soil erosion, thus reducing the cropland available for world food production. The loss of cropland is a serious problem because the World Health Organization and the Food and Agricultural Organization report that two-thirds of the world population is malnourished. Overall, soil is being lost from agricultural areas 10 to 40 times faster than the rate of soil formation imperiling humanity’s food security.

  9. Slurried solid media for simultaneous water purification and carbon dioxide removal from gas mixtures

    Science.gov (United States)

    Aines, Roger D.; Bourcier, William L.; Viani, Brian

    2013-01-29

    A slurried solid media for simultaneous water purification and carbon dioxide removal from gas mixtures includes the steps of dissolving the gas mixture and carbon dioxide in water providing a gas, carbon dioxide, water mixture; adding a porous solid media to the gas, carbon dioxide, water mixture forming a slurry of gas, carbon dioxide, water, and porous solid media; heating the slurry of gas, carbon dioxide, water, and porous solid media producing steam; and cooling the steam to produce purified water and carbon dioxide.

  10. Biotreatment of hydrocarbons from petroleum tank bottom sludges in soil slurries

    International Nuclear Information System (INIS)

    Ferrari, M.D.; Neirotti, E.; Albornoz, C.; Mostazo, M.R.; Cozzo, M.

    1996-01-01

    Biotreatment of oil wastes in aqueous slurries prepared with sandy loam soil and inoculated with selected soil cultures was evaluated. After 90 days, oil removal was 47%. Removal of each hydrocarbon class was 84% for saturates, 20% for aromatics, and 44% for asphaltenes. Resins increased by 68%. The use of a soil with a lower level of fine particles or minor organic matter content, or reinoculation with fresh culture did not improve oil elimination. Residual oil recovered from slurries was biotreated. Oil removal was 22%. Slurry-phase biotreatment showed less variability and faster oil removal than solid-phase biotreatment. (author)

  11. Disposal of oil cuttings by downhole fracturing injections : slurry product specifications issues

    International Nuclear Information System (INIS)

    Radzuan Junin

    1994-01-01

    The technique of using on-site injection of oil contaminated drill cuttings is attracting considerable attention as a cost effective means of complying with environmental legislation concerning discharges of drilling wastes. The slurrification and injection of oil based cuttings into a casing annulus, a process developed in 1989 by a major oil and gas producer/ operator, has proven to be a significant step toward reduction of such environmental waste. This paper discusses the development of the cuttings reinjection, slurrification, slurry properties and benefits of quality slurry, and behaviour of solid laden slurries in a fracture in conjunction with down-hole disposal operations

  12. On inhibition of dental erosion.

    Science.gov (United States)

    Rölla, Gunnar; Jonski, Grazyna; Saxegaard, Erik

    2013-11-01

    To examine the erosion-inhibiting effect of different concentrations of hydrofluoric acid. Thirty-six human molars were individually treated with 10 ml of 0.1 M citric acid for 30 min (Etch 1), acid was collected and stored until analysis. The teeth were randomly divided into six groups and then individually treated with 10 ml of one of six dilutions (from 0.1-1%) of hydrofluoric acid. The teeth were then again treated with citric acid (Etch 2). The individual acid samples from Etch 1 and 2 were analyzed for calcium by flame atomic absorption spectroscopy and difference in calcium loss was calculated. The highest erosion inhibiting effect was obtained in groups with the highest concentrations of hydrofluoric acid, where the pH was lowest, below pKa of 3.17, thus the hydrofluoric acids being mainly in an undissociated state. Diluted hydrofluoric acid is present in aqueous solution of SnF2 and TiF4 (which are known to inhibit dental erosion): SnF2 + 3H2O = Sn(OH)2 + 2HF + H2O and TiF4 + 5H2O = Ti(OH)4 + 4HF + H2O. It is also known that pure, diluted hydrofluoric acid can inhibit dental erosion. Teeth treated with hydrofluoric acid are covered by a layer of CaF2-like mineral. This mineral is acid resistant at pH acid resistant mineral, initiated by tooth enamel treatment with hydrofluoric acid. Hydrofluoric acid is different in having fluoride as a conjugated base, which provides this acid with unique properties.

  13. Erosive forms in rivers systems

    International Nuclear Information System (INIS)

    Una Alvarez, E. de; Vidal Romani, J. R.; Rodriguez Martinez-Conde, R.

    2009-01-01

    The purpose of this work is to analyze the geomorphological meaning of the concepts of stability/change and to study its influence on a fluvial erosion system. Different cases of fluvial potholes in Galicia (NW of the Iberian Peninsula) are considered. The work conclusions refer to the nature of the process and its morphological evolution in order to advance towards later contributions with respect of this type of systems. (Author) 14 refs.

  14. Physical properties and organic carbon content of a Rhodic Kandiudox fertilized with pig slurry and poultry litter

    Directory of Open Access Journals (Sweden)

    Luiz Paulo Rauber

    2012-08-01

    Full Text Available The impact of pig slurry and poultry litter fertilization on soils depends on the conditions of use and the amounts applied. This study evaluated the effect of organic fertilizers after different application periods in different areas on the physical properties and organic carbon contents of a Rhodic Kandiudox, in Concordia, Santa Catarina, in Southern Brazil. The treatments consisted of different land uses and periods of pig and poultry litter fertilization: silage maize (M7 years, silage maize (M20 years, annual ryegrass pasture (P3 years, annual ryegrass pasture (P15 years, perennial pasture (PP20 years, yerba mate tea (Mt20 years, native forest (NF, and native pasture without manure application (P0. The 0-5, 5-10 and 10-20 cm soil layers were sampled and analyzed for total organic carbon, total nitrogen and soil physical properties such as density, porosity, aggregation, degree of flocculation, and penetration resistance. The organic carbon levels in the cultivated areas treated with organic fertilizer were even lower than in native forest soil. The organic fertilizers and studied management systems reduced the flocculation degree of the clay particles, and low macroporosity was observed in some areas. Despite these changes, a good soil physical structure was maintained, e.g., soil density and resistance to penetration were below the critical limits, whereas aggregate stability was high, which is important to reduce water erosion in these areas with rugged terrain in western Santa Catarina, used for pig and poultry farming.

  15. Pyroclast/snow interactions and thermally driven slurry formation. Part 2: Experiments and theoretical extension to polydisperse tephra

    Science.gov (United States)

    Walder, J.S.

    2000-01-01

    Erosion of snow by pyroclastic flows and surges presumably involves mechanical scour, but there may be thermally driven phenomena involved as well. To investigate this possibility, layers of hot (up to 400??C), uniformly sized, fine- to medium-grained sand were emplaced vertically onto finely shaved ice ('snow'); thus there was no relative shear motion between sand and snow and no purely mechanical scour. In some cases large vapor bubbles, commonly more than 10 mm across, rose through the sand layer, burst at the surface, and caused complete convective overturn of the sand, which then scoured and mixed with snow and transformed into a slurry. In other cases no bubbling occurred and the sand passively melted its way downward into the snow as a wetting front moved upward into the sand. A continuum of behaviors between these two cases was observed. Vigorous bubbling and convection were generally favored by high temperature, small grain size, and small layer thickness. A physically based theory of heat- and mass transfer at the pyroclast/snow interface, developed in Part 1 of this paper, does a good job of explaining the observations as a manifestation of unstable vapor-driven fluidization. The theory, when extrapolated to the behavior of actual, poorly sorted pyroclastic flow sediments, leads to the prediction that the observed 'thermal-scour' phenomenon should also occur for many real pyroclastic flows passing over snow. 'Thermal scour' is therefore likely to be involved in the generation of lahars.

  16. Reclamation of a mine tailings pond by addition of marble waste and pig slurry for the development of aided phytostabilization

    International Nuclear Information System (INIS)

    Zornoza, R.; Faz, A.; Martínez-Martínez, S.; Acosta, J.A.; Gómez-López, M.D.; Muñoz, M.A.; Sánchez-Medrano, R.; Murcia, F.J.; Fernández Cortés, F.J.; López Martínez, E.; Espín de Gea, A.

    2017-01-01

    Abandoned tailings ponds produce environmental and human health hazards due to the transfer of heavy metals through wind and water erosion or leaching. To reduce these hazards, a reclamation strategy has been developed on a tailings pond based on aided phytostabilization. In 2011 marble mud and pig slurry were applied to the surface of a tailings pond and in the spring of 2012 thirteen native vegetal species were introduced. The evolution of different soil properties and the bio-available fraction of the heavy metals Cd, Pb and Zn were monitored for two years (2012-2013). The results showed that the pH, aggregate stability, organic carbon, total nitrogen and cation exchange capacity increased after the application of the amendments and the growth of vegetation, whilst the bio-available fraction of the heavy metals drastically decreased (90-99%). Thus, the strategy followed proved to be positive for reducing the availability of heavy metals and improving soil quality and fertility. These results are promising in areas with extractive activity of carbonated materials, since the generated waste can be used for the reclamation of soils affected by heavy metals, transforming a residual material into a useful by-product. [es

  17. The Impact of Selected Fluoridated Toothpastes on Dental Erosion in Profilometric Measurement.

    Science.gov (United States)

    Fita, Katarzyna; Kaczmarek, Urszula

    2016-01-01

    Some fluoridated toothpastes, available commercially, are described to have a protective effect against dental erosion. To evaluate the influence of the selected marketed toothpastes on the human enamel exposed to acid beverages. Enamel specimens from extracted human teeth were prepared (n = 40). Specimens were randomly divided into 10 experimental groups, 4 specimens each, which were subjected to acid challenge for 10 min using orange juice (pH 3.79) or Pepsi Cola (pH 2.58) and then immersed for 2 min into a slurry of five marketed toothpastes with distilled water (1 : 3 w/w). The tested toothpastes contained 1450 or 5000 ppm fluoride, CPP-ACP with 900 ppm fluoride, 1450 ppm fluoride with potassium nitrate 5%, all of them as sodium fluoride, and 700 ppm fluoride as amine and sodium fluoride with 3500 ppm SnCl2. Enamel roughness (Ra parameter) by contact profilometer at baseline and after exposure onto soft drinks and slurry was measured. Exposure to both beverages caused a similar increase of enamel surface roughness. After the specimens immersion into slurries of toothpastes with 1450 or 5000 ppm fluoride, 1450 ppm fluoride with potassium nitrate 5% and CPP-ACP with 900 ppm fluoride the significant decrease of Ra values were found, reaching the baseline values. However, toothpaste with 700 ppm fluoride and 3500 ppm SnCl2 did not cause any fall in Ra value, probably due to other mechanism of action. Within the limitation of the study we can conclude that the sodium fluoride toothpastes are able to restore the surface profile of enamel exposed shortly to acidic soft drinks.

  18. Erosion corrosion in wet steam

    International Nuclear Information System (INIS)

    Tavast, J.

    1988-03-01

    The effect of different remedies against erosion corrosion in wet steam has been studied in Barsebaeck 1. Accessible steam systems were inspected in 1984, 1985 and 1986. The effect of hydrogen peroxide injection of the transport of corrosion products in the condensate and feed water systems has also been followed through chemical analyses. The most important results of the project are: - Low alloy chromium steels with a chromium content of 1-2% have shown excellent resistance to erosion corrosion in wet steam. - A thermally sprayed coating has shown good resistance to erosion corrosion in wet steam. In a few areas with restricted accessibility minor attacks have been found. A thermally sprayed aluminium oxide coating has given poor results. - Large areas in the moisture separator/reheater and in steam extraction no. 3 have been passivated by injection of 20 ppb hydrogen peroxide to the high pressure steam. In other inspected systems no significant effect was found. Measurements of the wall thickness in steam extraction no. 3 showed a reduced rate of attack. - The injection of 20 ppb hydrogen peroxide has not resulted in any significant reduction of the iron level result is contrary to that of earlier tests. An increase to 40 ppb resulted in a slight decrease of the iron level. - None of the feared disadvantages with hydrogen peroxide injection has been observed. The chromium and cobalt levels did not increase during the injection. Neither did the lifetime of the precoat condensate filters decrease. (author)

  19. Flash pyrolysis of coal-solvent slurry prepared from the oxidized coal and the coal dissolved in solvent; Ichibu yokaishita sanka kaishitsutan slurry no jinsoku netsubunkai

    Energy Technology Data Exchange (ETDEWEB)

    Maki, T.; Mae, K.; Okutsu, H.; Miura, K. [Kyushu University, Fukuoka (Japan). Faculty of Engineering

    1996-10-28

    In order to develop a high-efficiency coal pyrolysis method, flash pyrolysis was experimented on slurry prepared by using liquid-phase oxidation reformed coal and a methanol-based solvent mixture. Australian Morwell coal was used for the experiment. The oxidized coal, into which carboxyl groups have been introduced, has the condensation structure relaxed largely, and becomes highly fluid slurry by means of the solvent. Char production can be suppressed by making the oxidation-pretreated coal into slurry, resulting in drastically improved pyrolytic conversion. The slurry was divided into dissolved solution, dried substance, extracted residue, and residual slurry, which were pyrolized independently. The dissolved solution showed very high conversion. Improvement in the conversion is contributed by separating the dissolved substances (coal macromolecules) at molecular levels, coagulating the molecules, suppressing cross-link formation, and reducing molecular weight of the dissolved substances. Oxidized coal can be dissolved to 80% or higher by using several kinds of mixed solvents. As a result of the dissolution, a possibility was suggested on pyrolysis which is easy in handling and high in conversion. 7 refs., 6 figs., 2 tabs.

  20. Comparison of erosion and erosion control works in Macedonia, Serbia and Bulgaria

    Directory of Open Access Journals (Sweden)

    Ivan Blinkov

    2013-12-01

    Natural conditions in the Balkan countries contribute to the appearance of various erosion forms and the intensity of the erosion processes. Over the history of these countries, people who settled this region used the available natural resources to fill their needs (tree cutting, incorrect plugging, overgrazing, which contributed to soil erosion. Organized erosion control works in the Balkans started in the beginning of the 20th century (1905 in Bulgaria. The highest intensity of erosion control works were carried out during the period 1945 – 1990. Various erosion control works were launched. Bulgaria had a large anti-erosion afforestation, almost 1 million ha. Bulgaria's ecological river restoration approach has been in use for almost 50 years. Serbia contributed significant erosion and torrent control works on hilly agricultural areas. Specific screen barrages and afforestation on extremely dry areas are characteristic in Macedonia. A common characteristic for all countries is a high decrease in erosion control works in the last 20 years.

  1. USAGE OF PLASTIC LITTER MADE FROM SEPARATED SLURRY IN FARM ANIMAL BREEDINGS ESPECIALLY IN CATTLE

    Directory of Open Access Journals (Sweden)

    M. ŠOCH

    2009-10-01

    Full Text Available The observation was performed in two dairy cows´ herds of Holstein breeding stabled in brick buildings with loose box stabling system. The separated slurry was used as litter in one of the building, classical stabling regime with straw litter was used in the other one. The experiment ascertained a significant tendency to reduction of microorganisms and parasites quantity in separated slurry modified by biometric treatment through the method of managed composting process. There was quite a small quantity of microorganisms and parasites in samples taken from litter of separated slurry and only after three weeks a gradual proliferation of them began. From the viewpoint of the dairy cows´ state of health, the quantity and quality of their milk production, the cleanness of their body surface, the periods of their lying and other ascertained welfare parameters under given microclimatic conditions the application of separated slurry as plastic litter fully complied.

  2. SYSTEM OF CONTROL AND MANAGEMENT OF THE PROCESS OF THE MORTAR SLURRY PREPARATION

    Directory of Open Access Journals (Sweden)

    D. M. Kukuj

    2007-01-01

    Full Text Available The technological schema of automatic flow line allowing to prepare with minimum charges of manual labor the refined from solid additives mortar slurry with stable density is presented in the article.

  3. Influence of coal slurry particle composition on pipeline hydraulic transportation behavior

    Science.gov (United States)

    Li-an, Zhao; Ronghuan, Cai; Tieli, Wang

    2018-02-01

    Acting as a new type of energy transportation mode, the coal pipeline hydraulic transmission can reduce the energy transportation cost and the fly ash pollution of the conventional coal transportation. In this study, the effect of average velocity, particle size and pumping time on particle composition of coal particles during hydraulic conveying was investigated by ring tube test. Meanwhile, the effects of particle composition change on slurry viscosity, transmission resistance and critical sedimentation velocity were studied based on the experimental data. The experimental and theoretical analysis indicate that the alter of slurry particle composition can lead to the change of viscosity, resistance and critical velocity of slurry. Moreover, based on the previous studies, the critical velocity calculation model of coal slurry is proposed.

  4. Slurry explosives containing the combination of nitrogen-base salt and hard solid particles as sensitizer

    Energy Technology Data Exchange (ETDEWEB)

    Lyerly, W.M.

    1971-11-02

    In recent years, blasting agents, particularly those of the type known as water gels or slurry explosives have gained considerable commercial acceptance. Generally, the slurry explosives are comprised of an inorganic oxidizing salt, predominantly ammonium nitrate, a thickening agent for the liquid, water, and fuel. The density, velocity of detonation, and ability to sustain detonation are increased so that the compositions propagate in small diameter boreholes. A water-bearing slurry explosive is described containing inorganic oxidizing salt, fuel, water and thickener together with nitrogen- base salt and solid particles having a hardness of at least 4 on the Mohs scale and that have an acoustic impedance at least 2 times that of the matrix of the slurry explosive. (15 claims)

  5. Life cycle assessment of pig slurry treatment technologies for nutrient redistribution in Denmark

    DEFF Research Database (Denmark)

    ten Hoeve, Marieke; Hutchings, Nicholas John; Peters, Gregory M.

    2014-01-01

    Animal slurry management is associated with a range of impacts on fossil resource use and the environment. The impacts are greatest when large amounts of nutrient-rich slurry from livestock production cannot be adequately utilised on adjacent land. To facilitate nutrient redistribution, a range...... of different technologies are available. This study comprised a life cycle assessment of the environmental impacts from handling 1000. kg of pig slurry ex-animal. Application of untreated pig slurry onto adjacent land was compared with using four different treatment technologies to enable nutrient...... on a combination of values derived from the literature and simulations with the Farm-N model for Danish agricultural and climatic conditions. The environmental impact categories assessed were climate change, freshwater eutrophication, marine eutrophication, terrestrial acidification, natural resource use, and soil...

  6. 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

  7. Strength properties of cement slurries with lightweights applied in oil and gas wells

    International Nuclear Information System (INIS)

    Bubnov, A S; Drilling Mud and Cement Slurry (Russian Federation))" data-affiliation=" (Head of Laboratory Drilling Mud and Cement Slurry (Russian Federation))" >Boyko, I A; Drilling Mud and Cement Slurry (Russian Federation))" data-affiliation=" (PhD, Engineer, Laboratory Drilling Mud and Cement Slurry (Russian Federation))" >Khorev, V S

    2015-01-01

    The article is focused on the cement stone strength properties resulted from lightweight cement slurries that meet GOST-1581-96 (state Standards) requirements. Exfoliated vermiculite, hollow aluminosilicate microspheres (HAMs), diatomite and perlite were used as lightweighting additives

  8. Estimation of methane emissions from slurry pits under pig and cattle confinements

    DEFF Research Database (Denmark)

    Petersen, Søren O.; Olsen, Anne B.; Elsgaard, Lars

    2016-01-01

    Quantifying in-house emissions of methane (CH4) from liquid manure (slurry) is difficult due to high background emissions from enteric processes, yet of great importance for correct estimation of CH4 emissions from manure management and effects of treatment Technologies such as anaerobic digestion...... less sensitive to uncertainties in VSd or slurry temperature. A model application indicated that losses of carbon in VS as CO2 may be much greater than losses as CH4. Implications of these results for the correct estimation of CH4 emissions from manure management, and for the mitigation potential...... and cattle slurry differed significantly at 0.030 and 0.011 kg CH4 kg-1 VS (volatile solids). Current estimates of CH4 emissions from pig and cattle manure management correspond to 0.032 and 0.015 kg CH4 kg-1, respectively, indicating that slurry pits under animal confinements are a significant source...

  9. Apparatus and method of measuring fluctuations of excavated mud amount in a slurry line

    International Nuclear Information System (INIS)

    Yamazaki, H.; Kubota, R.; Uchida, Y.; Kasuya, T.; Seki, N.

    1976-01-01

    An apparatus and method for measuring fluctuations in amount of soil in slurry or soil-containing fluid line is described. Each system of feeding the slurry typically to tunneling face and draining it therefrom in the slurry line is provided with gamma-ray densimeter and electromagnetic flow-meter to obtain respective amounts of soil only (dry-soil amounts) in the slurry flowing through each of said systems from respective outputs of these meters in each system, so that actually excavated amount through ground layer of a shielded excavator at the tunneling face can be measured by the difference between the respective dry-soil amounts. The excavator will be advanced depending on this measured amount

  10. Development of laboratory and process sensors to monitor particle size distribution of industrial slurries

    Energy Technology Data Exchange (ETDEWEB)

    Pendse, H.P.

    1992-10-01

    In this paper we present a novel measurement technique for monitoring particle size distributions of industrial colloidal slurries based on ultrasonic spectroscopy and mathematical deconvolution. An on-line sensor prototype has been developed and tested extensively in laboratory and production settings using mineral pigment slurries. Evaluation to date shows that the sensor is capable of providing particle size distributions, without any assumptions regarding their functional form, over diameters ranging from 0.1 to 100 micrometers in slurries with particle concentrations of 10 to 50 volume percents. The newly developed on-line sensor allows one to obtain particle size distributions of commonly encountered inorganic pigment slurries under industrial processing conditions without dilution.

  11. Field device to measure viscosity, density, and other slurry properties in drilled shafts : final report.

    Science.gov (United States)

    2016-04-01

    Proper performance of mineral slurries used to stabilize drilled shaft excavations is maintained by assuring the : density, viscosity, pH, and sand content stay within state specified limits. These limits have been set either by : past experience, re...

  12. PHYSICAL PROPERTIES OF KAOLIN/SAND SLURRY USED DURING SUBMERSIBLE MIXER PUMP TESTS AT TNX

    International Nuclear Information System (INIS)

    HANSEN, ERICH

    2005-01-01

    The purpose of this task is to characterize the physical properties of the kaolin/sand slurries used during the testing of a new submersible mixer pump (SMP) which had undergone performance testing at the TNX Waste Tank mockup facility from July 2004 through May 2005. During this time period, four identical SMPs were subjected to various water tests and four different tests using different batches of kaolin/sand slurries. The physical properties of the kaolin/sand slurries were measured for three of the four tests. In these tests, three different sample locations were used to pull samples, the SMP cooling water exit (CWE), the SMP fluid flow field (FFF), and SMP effective cleaning radius (ECR). The physical properties measured, though not for each sample, included rheology, weight percent total solids (wt% TS), density, kaolin/sand slurry particle size distribution (PSD), weight percent and particles size distribution of material greater than 45 microns

  13. Coal-water slurry fuel internal combustion engine and method for operating same

    Science.gov (United States)

    McMillian, Michael H.

    1992-01-01

    An internal combustion engine fueled with a coal-water slurry is described. About 90 percent of the coal-water slurry charge utilized in the power cycle of the engine is directly injected into the main combustion chamber where it is ignited by a hot stream of combustion gases discharged from a pilot combustion chamber of a size less than about 10 percent of the total clearance volume of main combustion chamber with the piston at top dead center. The stream of hot combustion gases is provided by injecting less than about 10 percent of the total coal-water slurry charge into the pilot combustion chamber and using a portion of the air from the main combustion chamber that has been heated by the walls defining the pilot combustion chamber as the ignition source for the coal-water slurry injected into the pilot combustion chamber.

  14. NPK NMR Sensor: Online Monitoring of Nitrogen, Phosphorus, and Potassium in Animal Slurry.

    Science.gov (United States)

    Sørensen, Morten K; Jensen, Ole; Bakharev, Oleg N; Nyord, Tavs; Nielsen, Niels Chr

    2015-07-07

    Knowledge of the actual content of nitrogen, phosphorus, and potassium (NPK) in animal slurry is highly important to optimize crop production and avoid environmental pollution when slurry is spread on agricultural fields. Here, we present a mobile, low-field nuclear magnetic resonance (NMR) sensor suitable for online monitoring of the NPK content in animal slurry as an alternative to crude estimates or tedious nonspecific, off-site laboratory analysis. The sensor is based on (14)N, (17)O, (31)P, and (39)K NMR in a digital NMR instrument equipped with a 1.5 T Halbach magnet for direct detection of ammonium N, total P, and K and indirect evaluation of the organic N content, covering all practical components of NPK in animal slurry. In correlation studies, the obtained NMR measurements show good agreement with reference measurements from commercial laboratories.

  15. Improvement in water-slurry circulation at the Chumakovskaya coal preparation plant

    Energy Technology Data Exchange (ETDEWEB)

    Nabokov, A.K.; Fedotov, B.P.; Mitlash, V.V.

    1988-02-01

    The Chumakovskaya coal preparation plant (Donetskugleobogashchenie association) was put into operation in 1935. It processes 570 t/h of coal slurry with an ash content of 38.6% and produces grade T coal for coking and power generation. Coal preparation technology used is described. Shortcomings of the system cause 130 kg of high ash slurries to be recirculated per m/sup 3/ of hydrocyclone drain. Mathematical analysis of the present process and of two improved variants is presented. The analysis permits variants for clarification of the recirculated water to be developed and evaluated and the best one to be selected. The optimum variant permits the amount of thin recirculated slurry to be reduced to 48% and the amount of granular slurry to 13%. Implementation of this variant at the Chumakovskaya coal preparation plant will ensure annual savings of 20,000 rubles.

  16. USAGE OF PLASTIC LITTER MADE FROM SEPARATED SLURRY IN FARM ANIMAL BREEDINGS ESPECIALLY IN CATTLE

    OpenAIRE

    M. ŠOCH; JANA ŠŤASTNÁ; V. PÁLKA; B VOSTOUPAL; P. NOVÁK; J. BROUČEK; B. ČERMÁK

    2009-01-01

    The observation was performed in two dairy cows´ herds of Holstein breeding stabled in brick buildings with loose box stabling system. The separated slurry was used as litter in one of the building, classical stabling regime with straw litter was used in the other one. The experiment ascertained a significant tendency to reduction of microorganisms and parasites quantity in separated slurry modified by biometric treatment through the method of managed composting process. There was quite a sma...

  17. Experiment of forced convection heat transfer using microencapsulated phase-change-material slurries

    International Nuclear Information System (INIS)

    Kubo, Shinji; Akino, Norio; Tanaka, Amane; Nagashima, Akira.

    1997-01-01

    The present study describes an experiment on forced convective heat transfer using a water slurry of Microencapsulated Phase-change-material. A normal paraffin hydrocarbon is microencapsulated by melamine resin, melting point of 28.1degC. The heat transfer coefficient and pressure drop in a circular tube were evaluated. The heat transfer coefficient using the slurry in case with and without phase change were compared to in case of using pure water. (author)

  18. KINETICS OF SLURRY PHASE FISCHER-TROPSCH SYSTHESIS

    International Nuclear Information System (INIS)

    Dragomir B. Bukur; Gilbert F. Froment; Tomasz Olewski

    2005-01-01

    This report covers the third year of this research grant under the University Coal Research program. The overall objective of this project is to develop a comprehensive kinetic model for slurry phase Fischer-Tropsch synthesis (FTS) on iron catalysts. This model will be validated with experimental data obtained in a stirred tank slurry reactor (STSR) over a wide range of process conditions. The model will be able to predict molar flow rates and concentrations of all reactants and major product species (H 2 O, CO 2 , linear 1- and 2-olefins, and linear paraffins) as a function of reaction conditions in the STSR. During the reporting period we utilized experimental data from the STSR, that were obtained during the first two years of the project, to perform vapor-liquid equilibrium (VLE) calculations and estimate kinetic parameters. We used a modified Peng-Robinson (PR) equation of state (EOS) with estimated values of binary interaction coefficients for the VLE calculations. Calculated vapor phase compositions were in excellent agreement with experimental values from the STSR under reaction conditions. Occasional discrepancies (for some of the experimental data) between calculated and experimental values of the liquid phase composition were ascribed to experimental errors. The VLE calculations show that the vapor and the liquid are in thermodynamic equilibrium under reaction conditions. Also, we have successfully applied the Levenberg-Marquardt method (Marquardt, 1963) to estimate parameters of a kinetic model proposed earlier by Lox and Froment (1993b) for FTS on an iron catalyst. This kinetic model is well suited for initial studies where the main goal is to learn techniques for parameter estimation and statistical analysis of estimated values of model parameters. It predicts that the chain growth parameter (α) and olefin to paraffin ratio are independent of carbon number, whereas our experimental data show that they vary with the carbon number. Predicted molar flow

  19. 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

  20. Characterization of the March 2017 Tank 15 Waste Removal Slurry Sample (Combination of Slurry Samples HTF-15-17-28 and HTF-15-17-29)

    Energy Technology Data Exchange (ETDEWEB)

    Reboul, S. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); King, W. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Coleman, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-05-09

    Two March 2017 Tank 15 slurry samples (HTF-15-17-28 and HTF-15-17-29) were collected during the second bulk waste removal campaign and submitted to SRNL for characterization. At SRNL, the two samples were combined and then characterized by a series of physical, elemental, radiological, and ionic analysis methods. Sludge settling as a function of time was also quantified. The characterization results reported in this document are consistent with expectations based upon waste type, process knowledge, comparisons between alternate analysis techniques, and comparisons with the characterization results obtained for the November 2016 Tank 15 slurry sample (the sample collected during the first bulk waste removal campaign).

  1. Noise Reduction Properties of an Experimental Bituminous Slurry with Crumb Rubber Incorporated by the Dry Process

    Directory of Open Access Journals (Sweden)

    Moisés Bueno

    2014-08-01

    Full Text Available Nowadays, cold technology for asphalt pavement in the field of road construction is considered as an alternative solution to conventional procedures from both an economic and environmental point of view. Among these techniques, bituminous slurry surfacing is obtaining an important role due to the properties of the obtained wearing course. The functional performance of this type of surfaces is directly related to its rough texture. Nevertheless, this parameter has a significant influence on the tire/road noise generation. To reduce this undesirable effect on the sound performance, new designs of elastic bituminous slurries have been developed. Within the FENIX project, this work presents the acoustical characterization of an experimental bituminous slurry with crumb rubber from wasted automobile tires incorporated by the dry process. The obtained results show that, under controlled operational parameters, the close proximity sound levels associated to the experimental slurry are considerably lower than those emitted by a conventional slurry wearing course. However, after one year of supporting traffic loads and different weather conditions, the evaluated bituminous slurry, although it conserves the original noise reduction properties in relation to the conventional one, noticeably increases the generated sound emission. Therefore, it is required to continue improving the design of experimental surfaces in order to enhance its long-term performance.

  2. Feasibility Studies on Pipeline Disposal of Concentrated Copper Tailings Slurry for Waste Minimization

    Science.gov (United States)

    Senapati, Pradipta Kumar; Mishra, Barada Kanta

    2017-06-01

    The conventional lean phase copper tailings slurry disposal systems create pollution all around the disposal area through seepage and flooding of waste slurry water. In order to reduce water consumption and minimize pollution, the pipeline disposal of these waste slurries at high solids concentrations may be considered as a viable option. The paper presents the rheological and pipeline flow characteristics of copper tailings samples in the solids concentration range of 65-72 % by weight. The tailings slurry indicated non-Newtonian behaviour at these solids concentrations and the rheological data were best fitted by Bingham plastic model. The influence of solids concentration on yield stress and plastic viscosity for the copper tailings samples were discussed. Using a high concentration test loop, pipeline experiments were conducted in a 50 mm nominal bore (NB) pipe by varying the pipe flow velocity from 1.5 to 3.5 m/s. A non-Newtonian Bingham plastic pressure drop model predicted the experimental data reasonably well for the concentrated tailings slurry. The pressure drop model was used for higher size pipes and the operating conditions for pipeline disposal of concentrated copper tailings slurry in a 200 mm NB pipe with respect to specific power consumption were discussed.

  3. Kinetic modeling of cement slurry synthesized with Henna extract in oil well acidizing treatments

    Directory of Open Access Journals (Sweden)

    Amir Hossein Aghajafari

    2016-06-01

    Full Text Available Acidizing treatment in petroleum reservoirs is a short-term and viable strategy to preserve the productivity of a well. There is a major concern for the degradation of cement sheath integrity, leading to poor zonal isolation and environmental issues. Therefore, it is essential to understand how the cement behaves when attacked by hydrochloric acid. In this study, a cement slurry by incorporation of the Henna extract, as an environmentally friendly cement additive, was synthesized as a potential solution to solve this problem. The characteristics of the treated cement slurry were compared with a reference slurry (w/c = 0.44 which is composed of only cement and water. A kinetic study was carried out to evaluate the adsorption behavior of the cement slurries exposed to an acid solution with 0.1 M HCl in a range of 25 to 55 °C conditions. The features of the cement slurries were evaluated by multiple analytical techniques such as XRD, FTIR, TG, and DSC analysis. From the experimental data, it is concluded that the second-order Lagergren kinetic model revealed to be the best in describing kinetic isotherms taken, because the margin between experimental and calculated values was minor for this model. The results of the characterization and HCl interaction kinetic studies underlined the prominent protective role of Henna extract-modified cement slurry in the enhancement of the cement resistance against acid attack and utilization in environmentally favorable oil well acidizing treatments.

  4. Nitrogen and phosphorus removal coupled with carbohydrate production by five microalgae cultures cultivated in biogas slurry.

    Science.gov (United States)

    Tan, Fen; Wang, Zhi; Zhouyang, Siyu; Li, Heng; Xie, Youping; Wang, Yuanpeng; Zheng, Yanmei; Li, Qingbiao

    2016-12-01

    In this study, five microalgae strains were cultured for their ability to survive in biogas slurry, remove nitrogen resources and accumulate carbohydrates. It was proved that five microalgae strains adapted in biogas slurry well without ammonia inhibition. Among them, Chlorella vulgaris ESP-6 showed the best performance on carbohydrate accumulation, giving the highest carbohydrate content of 61.5% in biogas slurry and the highest ammonia removal efficiency and rate of 96.3% and 91.7mg/L/d respectively in biogas slurry with phosphorus and magnesium added. Additionally, the absence of phosphorus and magnesium that can be adverse for biomass accumulation resulted in earlier timing of carbohydrate accumulation and magnesium was firstly recognized and proved as the influence factor for carbohydrate accumulation. Microalgae that cultured in biogas slurry accumulated more carbohydrate in cell, making biogas slurry more suitable medium for the improvement of carbohydrate content, thus can be regarded as a new strategy to accumulate carbohydrate. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. 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.

  6. 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.

  7. Research on numerical simulation and protection of transient process in long-distance slurry transportation pipelines

    Science.gov (United States)

    Lan, G.; Jiang, J.; Li, D. D.; Yi, W. S.; Zhao, Z.; Nie, L. N.

    2013-12-01

    The calculation of water-hammer pressure phenomenon of single-phase liquid is already more mature for a pipeline of uniform characteristics, but less research has addressed the calculation of slurry water hammer pressure in complex pipelines with slurry flows carrying solid particles. In this paper, based on the developments of slurry pipelines at home and abroad, the fundamental principle and method of numerical simulation of transient processes are presented, and several boundary conditions are given. Through the numerical simulation and analysis of transient processes of a practical engineering of long-distance slurry transportation pipeline system, effective protection measures and operating suggestions are presented. A model for calculating the water impact of solid and fluid phases is established based on a practical engineering of long-distance slurry pipeline transportation system. After performing a numerical simulation of the transient process, analyzing and comparing the results, effective protection measures and operating advice are recommended, which has guiding significance to the design and operating management of practical engineering of longdistance slurry pipeline transportation system.

  8. 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)

  9. Research on numerical simulation and protection of transient process in long-distance slurry transportation pipelines

    International Nuclear Information System (INIS)

    Lan, G; Jiang, J; Li, D D; Yi, W S; Zhao, Z; Nie, L N

    2013-01-01

    The calculation of water-hammer pressure phenomenon of single-phase liquid is already more mature for a pipeline of uniform characteristics, but less research has addressed the calculation of slurry water hammer pressure in complex pipelines with slurry flows carrying solid particles. In this paper, based on the developments of slurry pipelines at home and abroad, the fundamental principle and method of numerical simulation of transient processes are presented, and several boundary conditions are given. Through the numerical simulation and analysis of transient processes of a practical engineering of long-distance slurry transportation pipeline system, effective protection measures and operating suggestions are presented. A model for calculating the water impact of solid and fluid phases is established based on a practical engineering of long-distance slurry pipeline transportation system. After performing a numerical simulation of the transient process, analyzing and comparing the results, effective protection measures and operating advice are recommended, which has guiding significance to the design and operating management of practical engineering of longdistance slurry pipeline transportation system

  10. Attenuation measurements of ultrasound in a kaolin-water slurry. A linear dependence upon frequency

    International Nuclear Information System (INIS)

    Greenwood, M.S.; Mai, J.L.; Good, M.S.

    1993-01-01

    The attenuation of ultrasound through a kaolin-water slurry was measured for frequencies ranging from 0.5 to 3.0 MHz. The maximum concentration of the slurry was for a weight percentage of 44% (or a volume fraction of 0.24). The goal of these measurements was to assess the feasibility of using ultrasonic attenuation to determine the concentration of a slurry of known composition. The measurements were obtained by consecutively adding kaolin to the slurry and measuring the attenuation at each concentration. After reaching a maximum concentration a dilution technique was used, in which an amount of slurry was removed and water was added, to obtain the attenuation as a function of the concentration. The dilution technique was the more effective method to obtain calibration data. These measurements were carried out using two transducers, having a center frequency of 2.25 MHz, separated by 0.1016m (4.0 in.). The maximum attenuation measured in these experiments was about 100Np/m, but the experimental apparatus has the capability of measuring a larger attenuation if the distance between the two transducers is decreased. For a given frequency, the data show that ln V/V 0 depends linearly upon the volume fraction (V is the received voltage for the slurry and V 0 is that obtained for water). This indicated that each particle acts independently in attenuating ultrasound. 12 refs., 7 figs., 3 tabs

  11. The comparison of various approach to evaluation erosion risks and design control erosion measures

    Science.gov (United States)

    Kapicka, Jiri

    2015-04-01

    In the present is in the Czech Republic one methodology how to compute and compare erosion risks. This methodology contain also method to design erosion control measures. The base of this methodology is Universal Soil Loss Equation (USLE) and their result long-term average annual rate of erosion (G). This methodology is used for landscape planners. Data and statistics from database of erosion events in the Czech Republic shows that many troubles and damages are from local episodes of erosion events. An extent of these events and theirs impact are conditional to local precipitation events, current plant phase and soil conditions. These erosion events can do troubles and damages on agriculture land, municipally property and hydro components and even in a location is from point of view long-term average annual rate of erosion in good conditions. Other way how to compute and compare erosion risks is episodes approach. In this paper is presented the compare of various approach to compute erosion risks. The comparison was computed to locality from database of erosion events on agricultural land in the Czech Republic where have been records two erosion events. The study area is a simple agriculture land without any barriers that can have high influence to water flow and soil sediment transport. The computation of erosion risks (for all methodology) was based on laboratory analysis of soil samples which was sampled on study area. Results of the methodology USLE, MUSLE and results from mathematical model Erosion 3D have been compared. Variances of the results in space distribution of the places with highest soil erosion where compared and discussed. Other part presents variances of design control erosion measures where their design was done on based different methodology. The results shows variance of computed erosion risks which was done by different methodology. These variances can start discussion about different approach how compute and evaluate erosion risks in areas

  12. Cavitation erosion - scale effect and model investigations

    Science.gov (United States)

    Geiger, F.; Rutschmann, P.

    2015-12-01

    The experimental works presented in here contribute to the clarification of erosive effects of hydrodynamic cavitation. Comprehensive cavitation erosion test series were conducted for transient cloud cavitation in the shear layer of prismatic bodies. The erosion pattern and erosion rates were determined with a mineral based volume loss technique and with a metal based pit count system competitively. The results clarified the underlying scale effects and revealed a strong non-linear material dependency, which indicated significantly different damage processes for both material types. Furthermore, the size and dynamics of the cavitation clouds have been assessed by optical detection. The fluctuations of the cloud sizes showed a maximum value for those cavitation numbers related to maximum erosive aggressiveness. The finding suggests the suitability of a model approach which relates the erosion process to cavitation cloud dynamics. An enhanced experimental setup is projected to further clarify these issues.

  13. Mapping monthly rainfall erosivity in Europe

    DEFF Research Database (Denmark)

    Ballabio, C; Meusburger, K; Klik, A

    2017-01-01

    to Eastern Europe. The maps also show a clear delineation of areas with different erosivity seasonal patterns, whose spatial outline was evidenced by cluster analysis. The monthly erosivity maps can be used to develop composite indicators that map both intra-annual variability and concentration of erosive...... and seasonal R-factor maps and assess rainfall erosivity both spatially and temporally. During winter months, significant rainfall erosivity is present only in part of the Mediterranean countries. A sudden increase of erosivity occurs in major part of European Union (except Mediterranean basin, western part...... selected among various statistical models to perform the spatial interpolation due to its excellent performance, ability to model non-linearity and interpretability. The monthly prediction is an order more difficult than the annual one as it is limited by the number of covariates and, for consistency...

  14. Erosion and sedimentation caused by watercourse regulation

    International Nuclear Information System (INIS)

    Dahl, T.E.; Godtland, K.

    1995-01-01

    This report describes the observations made by SINTEF NHL in 1993 - 1994 on the development of erosion in three regulated lakes in Norway: Devdesjavri, Store Maalvatn and Gjevilvatnet. Surveys, profile levelling, water sample analyses, aerial photography etc were all used. Erosion was dramatic in all three magazines the first year of regulation and then slowed down. It has since remained relatively stable. However, there is a risk of further strong erosion connected with flooding tributaries, notably at low water such as usually occurs in spring. This is true in particular of the main river discharging into Devdesjavri, which is subject to landslides, wave and river erosion. In addition, ground water erosion may occur if the magazine is drained too fast. The report is lavishly illustrated with colour pictures of the effects of erosion. 21 refs., 15 figs., 13 tabs

  15. Varioliform erosions in the stomach and duodenum

    Energy Technology Data Exchange (ETDEWEB)

    Lotz, W.; Schulz, D.; Munkel, G.

    1984-04-01

    One thousand five hundred and eighty-three patients who were x-rayed for dyspepsia showed varioliform erosions in 15.3%. Men had an incidence of 9.8%, almost twice as common as in women (5.5%). Mucosal polyps, usually of the hyperplastic type, occurred in 2.4%. 15% of patients with gastric ulcers and 16% of patients with duodenal ulcers had varioliform erosions. On the other hand, amongst patients with erosions, 11% had gastric ulcers and 8.3% duodenal ulcers. The definitions of erosion which have been given in the literature are partly contradictory, and are discussed. Varioliform erosions, also known as complete erosions, may be acute or chronic. They are the third most common cause of bleeding from the upper gastrointestinal tract. With modern radiological methods of examining the stomach, they are no longer a rare finding. 5 figs.

  16. Varioliform erosions in the stomach and duodenum

    International Nuclear Information System (INIS)

    Lotz, W.; Schulz, D.; Munkel, G.

    1984-01-01

    One thousand five hundred and eighty-three patients who were x-rayed for dyspepsia showed varioliform erosions in 15.3%. Men had an incidence of 9.8%, almost twice as common as in women (5.5%). Mucosal polyps, usually of the hyperplastic type, occurred in 2.4%. 15% of patients with gastric ulcers and 16% of patients with duodenal ulcers had varioliform erosions. On the other hand, amongst patients with erosions, 11% had gastric ulcers and 8.3% duodenal ulcers. The definitions of erosion which have been given in the literature are partly contradictory, and are discussed. Varioliform erosions, also known as complete erosions, may be acute or chronic. They are the third most common cause of bleeding from the upper gastrointestinal tract. With modern radiological methods of examining the stomach, they are no longer a rare finding. (orig.) [de

  17. Assessment and management of dental erosion.

    Science.gov (United States)

    Wang, Xiaojie; Lussi, Adrian

    2010-07-01

    Studies have shown a growing trend toward increasing prevalence of dental erosion, associated with the declining prevalence of caries disease in industrialized countries. Erosion is an irreversible chemical process that results in tooth substance loss and leaves teeth susceptible to damage as a result of wear over the course of an individual's lifetime. Therefore, early diagnosis and adequate prevention are essential to minimize the risk of tooth erosion. Clinical appearance is the most important sign to be used to diagnose erosion. The Basic Erosive Wear Examination (BEWE) is a simple method to fulfill this task. The determination of a variety of risk and protective factors (patient-dependent and nutrition-dependent factors) as well as their interplay are necessary to initiate preventive measures tailored to the individual. When tooth loss caused by erosive wear reaches a certain level, oral rehabilitation becomes necessary. Copyright 2010 Elsevier Inc. All rights reserved.

  18. DENTAL EROSION IN PRIMARY DENTITION- A REVIEW

    Directory of Open Access Journals (Sweden)

    Rafi Shaik

    2017-06-01

    Full Text Available BACKGROUND The pattern of oral diseases has been influenced by ever changing human lifestyle. Tooth wear especially dental erosion has drawn increasing attention as risk factor for tooth damage or loss in recent years. It is a common condition in primary dentition compared to permanent dentition due to thinner and less mineralised enamel. However, it is more worrying, when this condition is being found in an alarming proportion among children. The presence of dental erosion in children is likely to be associated with a number of general health and dietary factors, but it is also aggravated by the relatively more rapid progression of erosion in the deciduous teeth. An understanding of the aetiologies and risk factors for erosion is important for early recognition of dental erosion to prevent serious irreversible damage to the dentition. This paper discusses the erosion in children with regard to its epidemiology, prevalence, clinical features, measurement and prevention.

  19. PROBLEMS OF SOIL PROTECTION FROM EROSION

    OpenAIRE

    M. Voloshuk; Natalia Kiriak

    2007-01-01

    In this article the problems of soil protection from erosion in Moldova are considered. The history (evolution) of erosive processes is generalized, the first items of information on presence washed off soils are marked. Purposeful study of soil erosion, development of measures of struggle with it were begun in Moldova at the end of 40 years. In connection with transition to new economic methods of conducting economy (farmers, rent, privatization of land) before pedologist, the experts of des...

  20. Influence of soil structure on contaminant leaching from injected slurry

    DEFF Research Database (Denmark)

    Amin, M. G. Mostofa; Pedersen, Christina Østerballe; Forslund, Anita

    2016-01-01

    at a rate of 50 t ha(-1) and followed with four irrigation events: 3.5-h period at 10 mm h(-1) after 1, 2, 3, and 4 weeks. The disturbed columns delayed the leaching of a conservative tracer and microorganisms in the first irrigation event compared to the intact columns due to the effect of disturbed...... macropore flow paths. The slurry constituents that ended up in or near the macropore flow paths of the intact soil were presumably washed out relatively quickly in the first event. For the last three events the intact soil leached fewer microorganisms than the disturbed soil due to the bypassing effect...... of water through the macropore flow path in the intact soil. Estrogen leached from the intact soil in the first event only, but for the disturbed soil it was detected in the leachates of last two events also. Leaching from the later events was attributed to higher colloid transport from the disturbed soils...

  1. Recovering low-turbidity cutting liquid from silicon slurry waste.

    Science.gov (United States)

    Tsai, Tzu-Hsuan; Shih, Yu-Pei

    2014-04-30

    In order to recover a low-turbidity polyalkylene glycol (PAG) liquid from silicon slurry waste by sedimentation, temperatures were adjusted, and acetone, ethanol or water was used as a diluent. The experimental results show that the particles in the waste would aggregate and settle readily by using water as a diluent. This is because particle surfaces had lower surface potential value and weaker steric stabilization in PAG-water than in PAG-ethanol or PAG-acetone solutions. Therefore, water is the suggested diluent for recovering a low-turbidity PAG (sedimentation. After 50 wt.% water-assisted sedimentation for 21 days, the solid content of the upper liquid reduced to 0.122 g/L, and the turbidity decreased to 44 NTU. The obtained upper liquid was then vacuum-distillated to remove water. The final recovered PAG with 0.37 NTU had similar viscosity and density to the unused PAG and could be reused in the cutting process. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Erosion products in disruption simulation experiments

    International Nuclear Information System (INIS)

    Safronov, V.; Arkhipov, N.; Bakhtin, V.; Barsuk, V.; Kurkin, S.; Mironova, E.; Toporkov, D.; Vasenin, S.; Zhitlukhin, A.; Arkhipov, I.; Werle, H.; Wuerz, H.

    1998-01-01

    Erosion of divertor materials under tokamak disruption event presents a serious problem of ITER technology. Erosion restricts the divertor lifetime and leads to production of redeposited layers of the material retaining large amount of tritium, which is a major safety issue for future fusion reactor. Since ITER disruptive heat loads are not achievable in existing tokamaks, material erosion is studied in special simulation experiments. Till now the simulation experiments have focused mainly on investigation of shielding effect and measurement of erosion rate. In the present work the properties of eroded and redeposited graphite are studied under condition typical for hard ITER disruption. (author)

  3. Reduction of surface erosion in fusion reactors

    International Nuclear Information System (INIS)

    Rossing, T.D.; Das, S.K.; Kaminsky, M.

    1976-01-01

    Some of the major processes leading to surface erosion in fusion reactors are reviewed briefly, including blistering by implanted gas, sputtering by ions, atoms, and neutrons, and vaporization by local heating. Surface erosion affects the structural integrity and limits the lifetime of reactor components exposed to plasma radiation. In addition, some of the processes leading to surface erosion also cause the release of plasma contaminants. Methods proposed to reduce surface erosion have included control of surface temperature, selection of materials with a favorable microstructure, chemical and mechanical treatment of surfaces, and employment of protective surface coatings, wall liners, and divertors. The advantages and disadvantages of some of these methods are discussed

  4. Erosive lichen planus: a therapeutic challenge.

    Science.gov (United States)

    Romero, Williams; Giesen, Laura; Navajas-Galimany, Lucas; Gonzalez, Sergio

    2016-01-01

    Erosive lichen planus is an uncommon variant of lichen planus. Chronic erosions of the soles, accompanied by intense and disabling pain, are some of its most characteristic manifestations. We present the case of a woman who developed oral and plantar erosive lichen planus associated with lichen planus pigmentosus and ungueal lichen planus that were diagnosed after several years. The patient failed to respond to multiple therapies requiring longstanding medication but remained refractory. Knowledge of the treatment options for erosive lichen planus is insufficient. Further research is required to clarify their effectiveness, ideally adopting an evidence-based methodology.

  5. Robotic weld overlay coatings for erosion control

    Science.gov (United States)

    The erosion of materials by the impact of solid particles has received increasing attention during the past twenty years. Recently, research has been initiated with the event of advanced coal conversion processes in which erosion plays an important role. The resulting damage, termed Solid Particle Erosion (SPE), is of concern primarily because of the significantly increased operating costs which result in material failures. Reduced power plant efficiency due to solid particle erosion of boiler tubes and waterfalls has led to various methods to combat SPE. One method is to apply coatings to the components subjected to erosive environments. Protective weld overlay coatings are particularly advantageous in terms of coating quality. The weld overlay coatings are essentially immune to spallation due to a strong metallurgical bond with the substrate material. By using powder mixtures, multiple alloys can be mixed in order to achieve the best performance in an erosive environment. However, a review of the literature revealed a lack of information on weld overlay coating performance in erosive environments which makes the selection of weld overlay alloys a difficult task. The objective of this project is to determine the effects of weld overlay coating composition and microstructure on erosion resistance. These results will lead to a better understanding of erosion mitigation in CFB's.

  6. The influence of rill density on soil erosion against USLE-soil erosion methode

    OpenAIRE

    Rizalihadi, A.M.; Faimah, B.E.; Nazia, C.L.

    2013-01-01

    Land and water is one of the major natural resource which has an important role for human life. Exploitation of land in catchment areas that not correspond to its carrying capacity will cause damage. One of the effect is increassing the soil erosion. Continuous erosion will also lead to increased sediment transport in rivers that disrupt the ship navigation on estuary due sediment accumulation. At present, soil erosion is estimated using USLE method, which is only limited to the erosion in th...

  7. Quantifying accelerated soil erosion through ecological site-based assessments of wind and water erosion

    Science.gov (United States)

    This work explores how organising soil erosion assessments using established groupings of similar soils (ecological sites) can inform systems for managing accelerated soil erosion. We evaluated aeolian sediment transport and fluvial erosion rates for five ecological sites in southern New Mexico, USA...

  8. Farmers' identification of erosion indicators and related erosion damage in the Central Highlands of Kenya

    NARCIS (Netherlands)

    Sterk, G.; Okoba, B.O.

    2006-01-01

    Most soil and water conservation planning approaches rely on empirical assessment methods and hardly consider farmers' knowledge of soil erosion processes. Farmers' knowledge of on-site erosion indicators could be useful in assessing the site-specific erosion risk before planning any conservation

  9. 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...

  10. Scoping erosion flow loop test results in support of Hanford WTP

    International Nuclear Information System (INIS)

    Duignan, M.; Imrich, K.; Fowley, M.; Restivo, M.; Reigel, M.

    2015-01-01

    The Waste Treatment and Immobilization Plant (WTP) will process Hanford Site tank waste by converting the waste into a stable glass form. Before the tank waste can be vitrified, the baseline plan is to process the waste through the Pretreatment (PT) Facility where it will be mixed in various process vessels using Pulse Jet Mixers (PJM) and transferred to the High Level Waste (HLW) or Low Activity Waste (LAW) vitrification facilities. The Department of Energy (DOE) and Defense Nuclear Facility Safety Board (DNFSB), as well as independent review groups, have raised concerns regarding the design basis for piping erosion in the PT Facility. Due to the complex nature of slurry erosion/corrosion wear and the unique conditions that exist within the PT Facility, additional testing has been recommended by these entities. Pipe loop testing is necessary to analyze the potential for localized wear at elbows and bends, close the outstanding PT and HLW erosion/corrosion technical issues, and underpin BNI's design basis for a 40-year operational life for black cell piping and vessels. SRNL is consulting with the DOE Office of River Protection (ORP) to resolve technical concerns related to piping erosion/corrosion (wear) design basis for PT. SRNL was tasked by ORP to start designing, building, and testing a flow loop to obtain long-term total-wear rate data using bounding simulant chemistry, operating conditions, and prototypical materials. The initial test involved a scoping paint loop to locate experimentally the potential high-wear locations. This information will provide a basis for the placement of the many sensitive wear measurement instruments in the appropriate locations so that the principal flow-loop test has the best chance to estimate long-term erosion and corrosion. It is important to note that the scoping paint loop test only utilized a bounding erosion simulant for this test. A full chemical simulant needs to be added for the complete test flow loop. The

  11. Monthly Rainfall Erosivity Assessment for Switzerland

    Science.gov (United States)

    Schmidt, Simon; Meusburger, Katrin; Alewell, Christine

    2016-04-01

    Water erosion is crucially controlled by rainfall erosivity, which is quantified out of the kinetic energy of raindrop impact and associated surface runoff. Rainfall erosivity is often expressed as the R-factor in soil erosion risk models like the Universal Soil Loss Equation (USLE) and its revised version (RUSLE). Just like precipitation, the rainfall erosivity of Switzerland has a characteristic seasonal dynamic throughout the year. This inter-annual variability is to be assessed by a monthly and seasonal modelling approach. We used a network of 86 precipitation gauging stations with a 10-minute temporal resolution to calculate long-term average monthly R-factors. Stepwise regression and Monte Carlo Cross Validation (MCCV) was used to select spatial covariates to explain the spatial pattern of R-factor for each month across Switzerland. The regionalized monthly R-factor is mapped by its individual regression equation and the ordinary kriging interpolation of its residuals (Regression-Kriging). As covariates, a variety of precipitation indicator data has been included like snow height, a combination of hourly gauging measurements and radar observations (CombiPrecip), mean monthly alpine precipitation (EURO4M-APGD) and monthly precipitation sums (Rhires). Topographic parameters were also significant explanatory variables for single months. The comparison of all 12 monthly rainfall erosivity maps showed seasonality with highest rainfall erosivity in summer (June, July, and August) and lowest rainfall erosivity in winter months. Besides the inter-annual temporal regime, a seasonal spatial variability was detectable. Spatial maps of monthly rainfall erosivity are presented for the first time for Switzerland. The assessment of the spatial and temporal dynamic behaviour of the R-factor is valuable for the identification of more susceptible seasons and regions as well as for the application of selective erosion control measures. A combination with monthly vegetation

  12. Clay slurry and engineered soils as containment technologies for remediation of contaminated sites

    International Nuclear Information System (INIS)

    Williams, J.R.; Dudka, S.; Miller, W.P.; Johnson, D.O.

    1997-01-01

    Clay Slurry and Engineered Soils are containment technologies for remediation of waste disposal sites where leaching, groundwater plumes and surface runoff of contaminants are serious ecological hazards to adjacent environments. This technology is a patent-pending process which involves the use of conditioned clay materials mixed with sand and water to form a readily pourable suspension, a clay slurry, which is either placed into a trench barrier system or allowed to de-water to create Engineered Soils. The Engineered Soil forms a layer impervious to water and air, therefore by inhibiting both water and oxygen from penetrating through the soil the material. This material can be installed in layers and as a vertical barrier to create a surface barrier containment system. The clay percentage in the clay slurry and Engineered Soils varies depending on site characteristics and desired performance standards. For example Engineered Soils with 1-2% of clay (dry wt.) had a hydraulic conductivity (K) of 10 -8 to 10 -1 cm/sec. Tests of tailing materials from a kyanite and pyrite mine showed that the clay slurry was effective not only in reducing the permeability of the treated tailings, but also in decreasing their acidity due to the inherent alkalinity of the clay. The untreated tailings had pH values in the range of 2.4 - 3.1; whereas, the effluent from clay and tailings mixtures had pH values in a slightly alkaline range (7.7-7.9). Pug-mills and high volume slurry pumps can be readily adapted for use in constructing and placing caps and creating Engineered Soils. Moreover, material on site or from a local sand supply can be used to create clay slurries and engineered soils. Clay materials used in cap construction are likewise readily available commercially. As a result, the clay slurry system is very cost effective compared to other capping systems, including the commonly used High Density Polyethylene (HDPE) liner systems

  13. Radiation hygienization of cattle and swine slurry with high energy electron beam

    International Nuclear Information System (INIS)

    Skowron, Krzysztof; Olszewska, Halina; Paluszak, Zbigniew; Zimek, Zbigniew; Kałuska, Iwona; Skowron, Karolina Jadwiga

    2013-01-01

    The research was carried out to assess the efficiency of radiation hygienization of cattle and swine slurry of different density using the high energy electron beam based on the inactivation rate of Salmonella ssp, Escherichia coli, Enterococcus spp and Ascaris suum eggs. The experiment was conducted with use of the linear electron accelerator Elektronika 10/10 in Institute of Nuclear Chemistry and Technology in Warsaw. The inoculated slurry samples underwent hygienization with high energy electron beam of 1, 3, 5, 7 and 10 kGy. Numbers of reisolated bacteria were determined according to the MPN method, using typical microbiological media. Theoretical lethal doses, D 90 doses and hygienization efficiency of high energy electron beam were determined. The theoretical lethal doses for all tested bacteria ranged from 3.63 to 8.84 kGy and for A. suum eggs from 4.07 to 5.83 kGy. Salmonella rods turned out to be the most sensitive and Enterococcus spp were the most resistant to electron beam hygienization. The effectiveness or radiation hygienization was lower in cattle than in swine slurry and in thick than in thin one. Also the species or even the serotype of bacteria determined the dose needed to inactivation of microorganisms. - Highlights: ► The hygienic efficiency of electron beam against slurry was researched. ► The hygienization efficiency depended on the slurry characteristics and microorganism species. ► In most of the cases 7 kGy dose was sufficient for slurry hygienization. ► Dose below 1 kGy allowed for 90% elimination of microorganism population. ► The radiation hygienization is a good alternative for typical slurry treatment methods

  14. 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.

  15. Evaluation of mitigation strategies to reduce ammonia losses from slurry fertilisation on arable lands

    Energy Technology Data Exchange (ETDEWEB)

    Carozzi, M., E-mail: marco.carozzi@unimi.it [University of Milan, Department of Agricultural and Environmental Sciences, via Celoria 2, 20133 Milan (Italy); Ferrara, R.M.; Rana, G. [Consiglio per la Ricerca e sperimentazione in Agricoltura, Research Unit for Cropping Systems in Dry Environments, via C. Ulpiani, 5 – 70125 Bari (Italy); Acutis, M. [University of Milan, Department of Agricultural and Environmental Sciences, via Celoria 2, 20133 Milan (Italy)

    2013-04-01

    To evaluate the best practices in reducing ammonia (NH{sub 3}) losses from fertilised arable lands, six field trials were carried out in three different locations in northern Italy. NH{sub 3} emissions from cattle slurry were estimated considering the spreading techniques and the field incorporation procedures. The measurements were performed using long term exposure samplers associated to the determination of the atmospheric turbulence and the use of the backward Lagrangian stochastic (bLS) model WindTrax. The results obtained indicate that the NH{sub 3} emission process was exhausted in the first 24–48 h after slurry spreading. The slurry incorporation technique was able to reduce the NH{sub 3} losses with respect to the surface spreading, where a contextual incorporation led to reductions up to 87%. However, the best abatement strategy for NH{sub 3} losses from slurry applications has proved to be the direct injection into the soil, with a reduction of about 95% with respect to the surface spreading. The results obtained highlight the strong dependence of the volatilisation phenomenon by soil and weather conditions. - Highlights: ► Ammonia emissions from land-application of slurry were quantified. ► We examined and compared six different agronomic treatments in three locations. ► The faster was the soil-incorporation of slurry, the lower was the ammonia loss. ► The direct injection of slurry was found to be the best abatement strategy. ► The environmental factors were able to strongly influence the ammonia emission.

  16. Fluid dynamic studies for a simulated Melton Valley Storage Tank slurry

    International Nuclear Information System (INIS)

    Hylton, T.D.; Youngblood, E.L.; Cummins, R.L.

    1994-07-01

    The Melton Valley Storage Tanks (MVSTs), are used for the collection and storage of remote-handled radioactive liquid wastes. These wastes, which were typically acidic when generated, were neutralized with the addition of sodium hydroxide to protect the storage tanks from corrosion, but this caused the transuranic and heavy metals to precipitate. These wastes will eventually need to be removed from the tanks for ultimate disposal. The objective of the research activities discussed in this report is to support the design of a pipeline transport system between the MVSTs and a treatment facility. Since the wastes in the MVSTs are highly radioactive, a surrogate slurry was developed for this study. Rheological properties of the simulated slurry were determined in a test loop in which the slurry was circulated through three pipeline viscometers of different diameters. Pressure drop data at varying flow rates were used to obtain shear stress and shear rate data. The data were analyzed, and the slurry rheological properties were analyzed by the Power Law model and the Bingham plastic model. The plastic viscosity and yield stress data obtained from the rheological tests were used as inputs for a piping design software package, and the pressure drops predicted by the software compared well with the pressure drop data obtained from the test loop. The minimum transport velocity was determine for the slurry by adding known nominal sizes of glass spheres to the slurry. However, it was shown that the surrogate slurry exhibited hindered settling, which may substantially decrease the minimum transport velocity. Therefore, it may be desired to perform additional tests with a surrogate with a lower concentration of suspended solids to determine the minimum transport velocity

  17. Thickness control and interface quality as functions of slurry formulation and casting speed in side-by-side tape casting

    DEFF Research Database (Denmark)

    Bulatova, Regina; Jabbari, Mirmasoud; Kaiser, Andreas

    2014-01-01

    A novel method of co-casting called side-by-side tape casting was developed aiming to form thin functionally graded films with varying properties within a single plane. The standard organic-based recipe was optimized to co-cast slurries into thick graded tapes. Performed numerical simulations...... identified the stable flow beneath the blade with a shear rate profile independent of slurry viscosity as long as the slurry load in the casting tank was low. Thickness and interface shape could be well predicted if the rheological behaviour of slurries is known and the processing parameters are well...

  18. Effect of organized assemblies. Part 4. Formulation of highly concentrated coal-water slurry using a natural surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Debadutta Das; Sagarika Panigrahi; Pramila K. Misra; Amalendu Nayak [Sambalpur University, Orissa (India). Centre of Studies in Surface Science and Technology

    2008-05-15

    Coal-water slurry has received considerable research nowadays due to its ability in substituting energy sources. The present work reports the formulation of highly concentrated coal-water slurry using a natural occurring surface active compound, saponin, extracted from the fruits of plant Sapindous laurifolia. The isolation of saponin from the plant and its surface activity has been discussed. The rheological characteristics of coal-water slurry have been investigated as a function of coal loading, ash content of coal, pH, temperature, and amount of saponin. The viscosity of the slurry and zeta potential are substantially decreased with concomitant shift of the isoelectric point of coal on adsorption of saponin to it. In the presence of 0.8% of saponin, coal-water slurry containing 64% weight fraction of coal could be achieved. The slurry is stable for a period of as long as 1 month in contrast to 4-5 h in the case of bare coal-water slurry. The results confirm the use of saponin as a suitable additive for coal-water slurry similar to the commercially available additive such as sodium dodecyl sulfate. Basing on the effect of pH on the zeta potential and viscosity of slurry, a suitable mechanism for saponin-coal interaction and orientation of saponin at the coal-water interface has been proposed. 47 refs., 12 figs., 5 tabs.

  19. Choosing co-substrates to supplement biogas production from animal slurry - A life cycle assessment of the environmental consequences

    DEFF Research Database (Denmark)

    Croxatto Vega, Giovanna Catalina; Ten Hoeve, Marieke; Birkved, Morten

    2014-01-01

    Biogas production from animal slurry can provide substantial contributions to reach renewable energy targets, yet due to the low methane potential of slurry, biogas plants depend on the addition of co-substrates to make operations profitable. The environmental performance of three underexploited co......-substrates, straw, organic household waste and the solid fraction of separated slurry, were assessed against slurry management without biogas production, using LCA methodology. The analysis showed straw, which would have been left on arable fields, to be an environmentally superior co-substrate. Due to its low...

  20. Rainfall erosivity in Brazil: A Review

    Science.gov (United States)

    In this paper, we review the erosivity studies conducted in Brazil to verify the quality and representativeness of the results generated and to provide a greater understanding of the rainfall erosivity (R-factor) in Brazil. We searched the ISI Web of Science, Scopus, SciELO, and Google Scholar datab...

  1. Interrill soil erosion processes on steep slopes

    Science.gov (United States)

    To date interrill erosion processes and regimes are not fully understood. The objectives are to 1) identify the erosion regimes and limiting processes between detachment and transport on steep slopes, 2) characterize the interactive effects between rainfall intensity and flow depth on sediment trans...

  2. Soil erosion dynamics response to landscape pattern

    NARCIS (Netherlands)

    Ouyang, W.; Skidmore, A.K.; Hao, F.; Wang, T.

    2010-01-01

    Simulating soil erosion variation with a temporal land use database reveals long-term fluctuations in landscape patterns, as well as priority needs for soil erosion conservation. The application of a multi-year land use database in support of a Soil Water Assessment Tool (SWAT) led to an accurate

  3. Wind erosion modelling in a Sahelian environment

    NARCIS (Netherlands)

    Faye-Visser, S.M.; Sterk, G.; Karssenberg, D.

    2005-01-01

    In the Sahel field observations of wind-blown mass transport often show considerable spatial variation related to the spatial variation of the wind erosion controlling parameters, e.g. soil crust and vegetation cover. A model, used to predict spatial variation in wind erosion and deposition is a

  4. Reduction of soil erosion on forest roads

    Science.gov (United States)

    Edward R. Burroughs; John G. King

    1989-01-01

    Presents the expected reduction in surface erosion from selected treatments applied to forest road traveledways, cutslopes, fillslopes, and ditches. Estimated erosion reduction is expressed as functions of ground cover, slope gradient, and soil properties whenever possible. A procedure is provided to select rock riprap size for protection of the road ditch.

  5. Forest road erosion control using multiobjective optimization

    Science.gov (United States)

    Matthew Thompson; John Sessions; Kevin Boston; Arne Skaugset; David Tomberlin

    2010-01-01

    Forest roads are associated with accelerated erosion and can be a major source of sediment delivery to streams, which can degrade aquatic habitat. Controlling road-related erosion therefore remains an important issue for forest stewardship. Managers are faced with the task to develop efficient road management strategies to achieve conflicting environmental and economic...

  6. Past, Present, Future Erosion at Locke Island

    Energy Technology Data Exchange (ETDEWEB)

    Bjornstad, Bruce N.

    2006-08-08

    This report describes and documents the erosion that has occurred along the northeast side of Locke Island over the last 10 to 20 years. The principal cause of this erosion is the massive Locke Island landslide complex opposite the Columbia River along the White Bluffs, which constricts the flow of the river and deflects the river's thalweg southward against the island.

  7. Tools for Ephemeral Gully Erosion Process Research

    Science.gov (United States)

    Techniques to quantify ephemeral gully erosion have been identified by USDA Natural Resources Conservation Service (NRCS) as one of gaps in current erosion assessment tools. One reason that may have contributed to this technology gap is the difficulty to quantify changes in channel geometry to asses...

  8. Developing empirical relationship between interrill erosion, rainfall ...

    African Journals Online (AJOL)

    In order to develop an empirical relationship for interrill erosion based on rainfall intensity, slope steepness and soil types, an interrill erosion experiment was conducted using laboratory rainfall simulator on three soil types (Vertisols, Cambisols and Leptosols) for the highlands of North Shewa Zone of Oromia Region.

  9. Rethinking erosion on Java: a reaction

    NARCIS (Netherlands)

    Graaff, de J.; Wiersum, K.F.

    1992-01-01

    In a recent article (Diemont et al., 1991) about erosion on Java, it has been postulated that low inputs, not surface erosion, is the main cause of low productivity of upland food crops on this island. In this article it is argued that this hypothesis is too simple. An analysis of empirical field

  10. The erosive potential of candy sprays

    NARCIS (Netherlands)

    Gambon, D.L.; Brand, H.S.; Nieuw Amerongen, A.V.

    2009-01-01

    Objective To determine the erosive potential of seven different commercially available candy sprays in vitro and in vivo. Material and methods The erosive potential was determined in vitro by measuring the pH and neutralisable acidity. The salivary pH and flow rate were measured in healthy

  11. Dental erosion: prevalence, incidence, and distribution

    NARCIS (Netherlands)

    Jager, D.H.J.; Amaechi, B.T.

    2015-01-01

    Dental erosion is one of the most common dental diseases and it is a growing problem. Numerous epidemiological studies have investigated the prevalence of dental erosion. For these studies different cross sections of the population are investigated. Large differences were found between countries,

  12. Backward erosion piping : Initiation and progression

    NARCIS (Netherlands)

    Van Beek, V.M.

    2015-01-01

    Backward erosion piping is an internal erosion mechanism during which shallow pipes are formed in the direction opposite to the flow underneath water-retaining structures as a result of the gradual removal of sandy material by the action of water. It is an important failure mechanism in both dikes

  13. Regionalization of monthly rainfall erosivity patternsin Switzerland

    Science.gov (United States)

    Schmidt, Simon; Alewell, Christine; Panagos, Panos; Meusburger, Katrin

    2016-10-01

    One major controlling factor of water erosion is rainfall erosivity, which is quantified as the product of total storm energy and a maximum 30 min intensity (I30). Rainfall erosivity is often expressed as R-factor in soil erosion risk models like the Universal Soil Loss Equation (USLE) and its revised version (RUSLE). As rainfall erosivity is closely correlated with rainfall amount and intensity, the rainfall erosivity of Switzerland can be expected to have a regional characteristic and seasonal dynamic throughout the year. This intra-annual variability was mapped by a monthly modeling approach to assess simultaneously spatial and monthly patterns of rainfall erosivity. So far only national seasonal means and regional annual means exist for Switzerland. We used a network of 87 precipitation gauging stations with a 10 min temporal resolution to calculate long-term monthly mean R-factors. Stepwise generalized linear regression (GLM) and leave-one-out cross-validation (LOOCV) were used to select spatial covariates which explain the spatial and temporal patterns of the R-factor for each month across Switzerland. The monthly R-factor is mapped by summarizing the predicted R-factor of the regression equation and the corresponding residues of the regression, which are interpolated by ordinary kriging (regression-kriging). As spatial covariates, a variety of precipitation indicator data has been included such as snow depths, a combination product of hourly precipitation measurements and radar observations (CombiPrecip), daily Alpine precipitation (EURO4M-APGD), and monthly precipitation sums (RhiresM). Topographic parameters (elevation, slope) were also significant explanatory variables for single months. The comparison of the 12 monthly rainfall erosivity maps showed a distinct seasonality with the highest rainfall erosivity in summer (June, July, and August) influenced by intense rainfall events. Winter months have the lowest rainfall erosivity. A proportion of 62 % of

  14. Erosion testing of hard materials and coatings

    Energy Technology Data Exchange (ETDEWEB)

    Hawk, Jeffrey A.

    2005-04-29

    Erosion is the process by which unconstrained particles, usually hard, impact a surface, creating damage that leads to material removal and component failure. These particles are usually very small and entrained in fluid of some type, typically air. The damage that occurs as a result of erosion depends on the size of the particles, their physical characteristics, the velocity of the particle/fluid stream, and their angle of impact on the surface of interest. This talk will discuss the basics of jet erosion testing of hard materials, composites and coatings. The standard test methods will be discussed as well as alternative approaches to determining the erosion rate of materials. The damage that occurs will be characterized in genera1 terms, and examples will be presented for the erosion behavior of hard materials and coatings (both thick and thin).

  15. Modelling rainfall erosion resulting from climate change

    Science.gov (United States)

    Kinnell, Peter

    2016-04-01

    It is well known that soil erosion leads to agricultural productivity decline and contributes to water quality decline. The current widely used models for determining soil erosion for management purposes in agriculture focus on long term (~20 years) average annual soil loss and are not well suited to determining variations that occur over short timespans and as a result of climate change. Soil loss resulting from rainfall erosion is directly dependent on the product of runoff and sediment concentration both of which are likely to be influenced by climate change. This presentation demonstrates the capacity of models like the USLE, USLE-M and WEPP to predict variations in runoff and erosion associated with rainfall events eroding bare fallow plots in the USA with a view to modelling rainfall erosion in areas subject to climate change.

  16. Erosion Pressure on the Danish Coasts

    DEFF Research Database (Denmark)

    Sørensen, Carlo Sass; Sørensen, Per; Kroon, Aart

    Coastlines around the world are receding due to coastal erosion.With rising sea levels and a potential climatic deterioration due to climate change, erosion rates are likely to increase at many locations in the future.Together with the current preference of people to settle near or directly...... by the ocean, coastal erosion issues become increasingly more important to the human values at risk. Along many Danish coastlines, hard structures already act as coastal protection in the form of groins, breakwaters, revetments etc. These eroding coasts however still lack sand and where the public, in general......, neglects the need for sand replenishment i.e. in the form of repeated sand nourishments. Here we present a conceptual model and method for dividing coastal erosion into acute and chronic erosion pressure, respectively. We focus on the model use for management and climate change adaptation purposes...

  17. Dietary assessment and counseling for dental erosion.

    Science.gov (United States)

    Marshall, Teresa A

    2018-02-01

    Dental erosion occurs after exposure to intrinsic or extrinsic acids. Exposure to intrinsic gastrointestinal acids is associated with anorexia nervosa, bulimia nervosa, rumination syndrome, or gastroesophageal reflux. Extrinsic dietary acids from foods or beverages also can cause erosion, particularly when exposure is prolonged by holding or swishing behaviors. Clinicians should screen patients exhibiting dental erosion for anorexia nervosa, bulimia nervosa, rumination syndrome, and gastroesophageal reflux disease. Clinicians should screen patients without a medical explanation for their erosion for exposure to acidic foods and beverages, particularly for habits that prolong exposure. Identification of intrinsic and extrinsic acid exposures and recommendations to minimize exposures are important to prevent erosion and maintain oral health. Copyright © 2018 American Dental Association. Published by Elsevier Inc. All rights reserved.

  18. Medication-related dental erosion: a review.

    Science.gov (United States)

    Thomas, Manuel S; Vivekananda Pai, A R; Yadav, Amit

    2015-10-01

    Dental erosion has become a major problem that affects the long-term health of the dentition. Among the various potential causes for erosive tooth wear, the different drugs prescribed for patients may be overlooked. Several therapeutic medications can directly or indirectly be associated with dental erosion. It is the responsibility of oral health providers to make both patients and colleagues aware of drugs that may contribute to this condition. Therefore, the purpose of this discussion is to provide an overview of the various therapeutic medications that can be related to tooth erosion. The authors also include precautionary measures-summarized as The 9 Rs-to avoid or at least reduce medication-induced erosion.

  19. Soil erosion processes on sloping land using REE tracer

    International Nuclear Information System (INIS)

    Shen Zhenzhou; Liu Puling; Yang Mingyi; Lian Zhenlong; Ju Tongjun; Yao Wenyi; Li Mian

    2007-01-01

    Sheet erosion is the main performance in the slope soil erosion process at the primary stage of natural rainfall. For three times of rainfall during experiment, the ratios of sheet erosion to total erosion account for 71%, 48% and 49% respectively, which showed that the sloping erosion was still at the primary stage from sheet erosion to rill erosion. With the rainfall going, the rill erosion amount increase. It showed that soil erosion was changing from sheet erosion to rill erosion. The sources of sediment from different sections of the plot were analyzed, and the results indicated that whatever the sheet erosion changed, the ratio erosion of upper part of surface soil was always lower than 10%. Sheet erosion came mainly from the lower section of surface soil. With the ratios to the amount of total rill erosion changes, the rill erosion amount of each section regularly changes too. The general conclusion is that when the rainfall ends, relative erosion of different slope element to the foot of slope is: 1 meter away accounts for 16%, 2-4 meters away is 6% and 5-9 meters away is 3%. The ratio of rill erosion amount of these three slope element is 5:2:1, which shows the rill erosion amount are mainly from the slope element of 4 meters from the foot of slope. (authors)

  20. SCOPING STUDIES TO DEVELOP A METHOD TO DETERMINE PARTICLE SIZE IN SIMULANT SLUDGE SLURRIES BY SIEVING

    International Nuclear Information System (INIS)

    DAMON, CLICK

    2005-01-01

    A physical separation method (i.e. sieving) was investigated to determine particle size distribution in non-radioactive sludge slurry simulants with the goal of implementation into the SRNL (Savannah River National Laboratory) shielded cells for use with radioactive sludge slurries. The investigation included obtaining the necessary experimental equipment, developing accessory equipment for use with the sieve shaker (to be able to sieve simulant slurries with aqueous solutions), sieving three different simulant slurries through a number of sieves and determining the particle size distribution gravimetrically, and developing a sufficient cleaning protocol of the sieves for re-use. The experimental protocol involved successive sieving of a NIST standard (to check the particle size retention of the sieves) and three non-radioactive slurry simulants (Batch 3 Tank 40 Test 3, Tank 40 Drum 3 and CETL Sludge Batch 2, which had been previously characterized by Microtrac analysis) through smaller and smaller sieves (150 microns x 5 microns) via use of the wet sieving system or by hand. For each of the three slurries, duplicate experiments were carried out using filtered supernate and DI water (to check the accuracy of the method versus Microtrac data) to sieve the slurry. Particle size determinations using the wet sieving system with DI water agree well with Microtrac data on a volume basis and in some cases the sieving data may be more accurate particularly if the material sieved had large particles. A correction factor had to be applied to data obtained from experiments done with supernate due to the dissolved solids which dried upon the sieves in the drying stage of the experiments. Upon subtraction of the correction factors, the experimental results were very similar to those obtained with DI water. It should be noted that approximately 250 mL of each of three simulant slurries was necessary to have enough filtered supernate available to carry out the experiments. The

  1. Erosion resistance comparison of alternative surface treatments

    Science.gov (United States)

    Česánek, Z.; Schubert, J.; Houdková, Š.

    2017-05-01

    Erosion is a process characterized by the particle separation and the damage of component functional surfaces. Thermal spraying technology HP/HVOF (High Pressure / High Velocity Oxygen Fuel) is commonly used for protection of component surfaces against erosive wear. Alloy as well as cermet based coatings meet the requirements for high erosion resistance. Wear resistance is in many cases the determining property of required component functioning. The application suitability of coating materials is particularly influenced by different hardness. This paper therefore presents an erosion resistance comparison of alloy and cermet based coatings. The coatings were applied on steel substrates and were subjected to the erosive test using the device for evaluation of material erosion resistance working on the principle of centrifugal erodent flow. Abrasive sand Al2O3 with grain size 212-250 μm was selected as an erosive material. For this purpose, the specimens were prepared by thermal spraying technology HP/HVOF using commercially available powders Stellite 6, NiCrBSi, Cr3C2-25%NiCr, Cr3C2-25%CoNiCrAlY, Hastelloy C-276 and experimental coating TiMoCN-29% Ni. Erosion resistance of evaluated coatings was compared with erosive resistance of 1.4923 high alloyed steel without nitridation and in nitrided state and further with surface treatment using technology PVD. According to the evaluation, the resulting erosive resistance depends not only on the selected erodent and surface protection, but also on the erodent impact angle.

  2. Dynamic Analysis of Soil Erosion in Songhua River Watershed

    Science.gov (United States)

    Zhang, Yujuan; Li, Xiuhai; Wang, Qiang; Liu, Jiang; Liang, Xin; Li, Dan; Ni, Chundi; Liu, Yan

    2018-01-01

    In this paper, based on RS and GIS technology and Revised Universal Soil Loss Equation (RUSLE), the soil erosion dynamic changes during the two periods of 1990 and 2010 in Bin County was analyzed by using the Landsat TM data of the two periods, so as to reveal the soil erosion spatial distribution pattern and spatial and temporal dynamic evolution rule in the region. The results showed that: the overall patterns of soil erosion were basically the same in both periods, mainly featuring slight erosion and mild erosion, with the area proportions of 80.68% and 74.71% respectively. The slight and extremely intensive erosion changing rates showed a narrowing trend; mild, moderate and intensive erosion was increasing, with a trend of increased soil erosion; mild and intensive erosion were developing towards moderate erosion and moderate and extremely intensive erosion were progressing towards intensive erosion.

  3. Area 3, SRC-II coal slurry preheater studies report for the technical data analysis program

    Energy Technology Data Exchange (ETDEWEB)

    1984-08-01

    This report reviews the raw data gathered from the Preheater B test runs at Ft. Lewis, and also the Preheater B results presented in the Solvent Refined Coal (SRC) Process Final Report, Volumes 1 and 2 of Slurry Preheater Design, SRC-II Process and the Ft. Lewis Slurry Preheater Data Analysis, 1 1/2 Inch Coil by Gulf Science and Technology Corporation of Pittsburgh, Pennsylvania. attempts were made to correlate several variables not previously considered with slurry viscosity and thermal conductivity. Only partial success was realized. However, in the process of attempting to correlate these variables an understanding of why some variables could not be correlated was achieved. An attempt was also made, using multiple linear regression, to correlate coal slurry viscosity and thermal conductivity with several independent variables among which were temperature, coal concentration, total solids, coal type, slurry residence time, shear rate, and unit size. The final correlations included some, but not all, of these independent variables. This report is not a stand alone document and should be considered a supplement to work already done. It should be read in conjunction with the reports referenced above.

  4. The effect on slurry water as a fresh water replacement in concrete properties

    Science.gov (United States)

    Kadir, Aeslina Abdul; Shahidan, Shahiron; Hai Yee, Lau; Ikhmal Haqeem Hassan, Mohd; Bakri Abdullah, Mohd Mustafa Al

    2016-06-01

    Concrete is the most widely used engineering material in the world and one of the largest water consuming industries. Consequently, the concrete manufacturer, ready mixed concrete plant is increased dramatically due to high demand from urban development project. At the same time, slurry water was generated and leading to environmental problems. Thus, this paper is to investigate the effect of using slurry water on concrete properties in term of mechanical properties. The basic wastewater characterization was investigated according to USEPA (Method 150.1 & 300.0) while the mechanical property of concrete with slurry water was compared according to ASTM C1602 and BS EN 1008 standards. In this research, the compressive strength, modulus of elasticity and tensile strength were studied. The percentage of wastewater replaced in concrete mixing was ranging from 0% up to 50%. In addition, the resulted also suggested that the concrete with 20% replacement of slurry water was achieved the highest compressive strength and modulus of elasticity compared to other percentages. Moreover, the results also recommended that concrete with slurry water mix have better compressive strength compared to control mix concrete.

  5. Identification of Inhibitors in Lignocellulosic Slurries and Determination of Their Effect on Hydrocarbon-Producing Microorganisms

    Directory of Open Access Journals (Sweden)

    Shihui Yang

    2018-04-01

    Full Text Available The aim of this work was to identify inhibitors in pretreated lignocellulosic slurries, evaluate high-throughput screening strategies, and investigate the impact of inhibitors on potential hydrocarbon-producing microorganisms. Compounds present in slurries that could inhibit microbial growth were identified through a detailed analysis of saccharified slurries by applying a combination of approaches of high-performance liquid chromatography, GC-MS, LC-DAD-MS, and ICP-MS. Several high-throughput assays were then evaluated to generate toxicity profiles. Our results demonstrated that Bioscreen C was useful for analyzing bacterial toxicity but not for yeast. AlamarBlue reduction assay can be a useful high-throughput assay for both bacterial and yeast strains as long as medium components do not interfere with fluorescence measurements. In addition, this work identified two major inhibitors (furfural and ammonium acetate for three potential hydrocarbon-producing bacterial species that include Escherichia coli, Cupriavidus necator, and Rhodococcus opacus PD630, which are also the primary inhibitors for ethanologens. This study was strived to establish a pipeline to quantify inhibitory compounds in biomass slurries and high-throughput approaches to investigate the effect of inhibitors on microbial biocatalysts, which can be applied for various biomass slurries or hydrolyzates generated through different pretreatment and enzymatic hydrolysis processes or different microbial candidates.

  6. An investigation on characterizing dense coal-water slurry with ultrasound: theoretical and experimental method

    Energy Technology Data Exchange (ETDEWEB)

    Xue, M.H.; Su, M.X.; Dong, L.L.; Shang, Z.T.; Cai, X.S. [Shanghai University of Science & Technology, Shanghai (China)

    2010-07-01

    Particle size distribution and concentration in particulate two-phase flow are important parameters in a wide variety of industrial areas. For the purpose of online characterization in dense coal-water slurries, ultrasonic methods have many advantages such as avoiding dilution, the capability for being used in real time, and noninvasive testing, while light-based techniques are not capable of providing information because optical methods often require the slurry to be diluted. In this article, the modified Urick equation including temperature modification, which can be used to determine the concentration by means of the measurement of ultrasonic velocity in a coal-water slurry, is evaluated on the basis of theoretical analysis and experimental study. A combination of the coupled-phase model and the Bouguer-Lambert-Beer law is employed in this work, and the attenuation spectrum is measured within the frequency region from 3 to 12 MHz. Particle size distributions of the coal-water slurry at different volume fractions are obtained with the optimum regularization technique. Therefore, the ultrasonic technique presented in this work brings the possibility of using ultrasound for online measurements of dense slurries.

  7. Escherichia coli Contamination of Lettuce Grown in Soils Amended with Animal Slurry

    DEFF Research Database (Denmark)

    Jensen, Annette Nygaard; Storm, Christina; Forslund, Anita

    2013-01-01

    A pilot study was conducted to assess the transfer of Escherichia coli from animal slurry fertilizer to lettuce, with E. coli serving as an indicator of fecal contamination and as an indicator for potential bacterial enteric pathogens. Animal slurry was applied as fertilizer to three Danish agric...... types between slurry, soil, and lettuce. The frequent finding of fecal-contaminated lettuce indicates that human pathogens such as Salmonella and Campylobacter can be present and represent food safety hazards.......A pilot study was conducted to assess the transfer of Escherichia coli from animal slurry fertilizer to lettuce, with E. coli serving as an indicator of fecal contamination and as an indicator for potential bacterial enteric pathogens. Animal slurry was applied as fertilizer to three Danish....... coli. A relatively higher frequency of E. coli in lettuce compared with the soil samples at harvest suggests environmental sources of fecal contamination, e.g., wildlife. The higher frequency was supported by the finding of 21 different PFGE types among the E. coli isolates, with only a few common PFGE...

  8. Biodegradation of aged polycyclic aromatic hydrocarbons (PAHs) by microbial consortia in soil and slurry phases.

    Science.gov (United States)

    Li, Xiaojun; Li, Peijun; Lin, Xin; Zhang, Chungui; Li, Qi; Gong, Zongqiang

    2008-01-15

    Microbial consortia isolated from aged oil-contaminated soil were used to degrade 16 polycyclic aromatic hydrocarbons (15.72 mgkg(-1)) in soil and slurry phases. The three microbial consortia (bacteria, fungi and bacteria-fungi complex) could degrade polycyclic aromatic hydrocarbons (PAHs), and the highest PAH removals were found in soil and slurry inoculated with fungi (50.1% and 55.4%, respectively). PAHs biodegradation in slurry was lower than in soil for bacteria and bacteria-fungi complex inoculation treatments. Degradation of three- to five-ring PAHs treated by consortia was observed in soil and slurry, and the highest degradation of individual PAHs (anthracene, fluoranthene, and benz(a)anthracene) appeared in soil (45.9-75.5%, 62-83.7% and 64.5-84.5%, respectively) and slurry (46.0-75.8%, 50.2-86.1% and 54.3-85.7%, respectively). Therefore, inoculation of microbial consortia (bacteria, fungi and bacteria-fungi complex) isolated from in situ contaminated soil to degrade PAHs could be considered as a successful method.

  9. Evaluation of planarization performance for a novel alkaline copper slurry under a low abrasive concentration

    International Nuclear Information System (INIS)

    Jiang Mengting; Liu Yuling; Yuan Haobo; Chen Guodong; Liu Weijuan

    2014-01-01

    A novel alkaline copper slurry that possesses a relatively high planarization performance is investigated under a low abrasive concentration. Based on the action mechanism of CMP, the feasibility of using one type of slurry in copper bulk elimination process and residual copper elimination process, with different process parameters, was analyzed. In addition, we investigated the regular change of abrasive concentration effect on copper and tantalum removal rate and within wafer non-uniformity (WIWNU) in CMP process. When the abrasive concentration is 3 wt%, in bulk elimination process, the copper removal rate achieves 6125 Å/min, while WIWNU is 3.5%, simultaneously. In residual copper elimination process, the copper removal rate is approximately 2700 Å/min, while WIWNU is 2.8%. Nevertheless, the tantalum removal rate is 0 Å/min, which indicates that barrier layer isn't eliminated in residual copper elimination process. The planarization experimental results show that an excellent planarization performance is obtained with a relatively high copper removal rate in bulk elimination process. Meanwhile, after residual copper elimination process, the dishing value increased inconspicuously, in a controllable range, and the wafer surface roughness is only 0.326 nm (sq < 1 nm) after polishing. By comparison, the planarization performance and surface quality of alkaline slurry show almost no major differences with two kinds of commercial acid slurries after polishing. All experimental results are conducive to research and improvement of alkaline slurry in the future. (semiconductor technology)

  10. 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.

  11. Spring barley yield and nitrogen recovery after application of peat manure and pig slurry

    Directory of Open Access Journals (Sweden)

    P. K. MATTILA

    2008-12-01

    Full Text Available The effectiveness of peat manure, manufactured of pig slurry and moderately humified Sphagnum peat (slurry:peat ca. 1:1.5 v/v, as nitrogen (N source for spring barley was investigated in a four.year field experiment on a clay loam soil in south-western Finland. Pig slurry, NPK fertilizer and plain peat were used as references. Manures were incorporated before sowing or surface-applied after sowing in spring at an ammoniacal N rate of.54.106 kg.ha-1 with or without supplementary NPK fertilizer (40.kg N.ha-1. Soil moisture conditions were varied by different irrigation treatments. Peat manure produced 5.15% higher grain yields than pig slurry, with the largest difference after surface application. Incorporation was more important for slurry than for peat manure in increasing N uptake and yield. Soil moisture deficit in spring and early summer limited the availability of manure N. Part of the manure N that was not available in the early growing period was apparently taken up by the crop later. Consequently, N concentration tended to be higher with lower yields, and differences in the recovery of manure N were smaller than the differences in grain yield. Supplementation of manures with inorganic fertilizer N increased yield by 37%, on average, and improved the N recovery.;

  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. Biological treatment of soils contaminated with hydrophobic organics using slurry and solid phase techniques

    International Nuclear Information System (INIS)

    Cassidy, D.P.; Irvine, R.L.

    1995-01-01

    Both slurry-phase and solid-phase bioremediation are effective ex situ soil decontamination methods. Slurry is energy intensive relative to solid-phase treatment, but provides homogenization and uniform nutrient distribution. Limited contaminant bioavailability at concentrations above the required cleanup level reduces biodegradation rates and renders solid phase bioremediation more cost effective than complete treatment in a bioslurry reactor. Slurrying followed by solid-phase bioremediation combines the advantages and minimizes the weaknesses of each treatment method when used alone. A biological treatment system consisting of slurrying followed by aeration in solid phase bioreactors was developed and tested in the laboratory using a silty clay load contaminated with diesel fuel. The first set of experiments was designed to determine the impact of the water content and mixing time during slurrying on the ate and extent of contaminant removal in continuously aerated solid phase bioreactors. The second set of experiments compared the volatile and total diesel fuel removal in solid phase bioreactors using periodic and continuous aeration strategies

  14. Transport of veterinary antibiotics in overland flow following the application of slurry to arable land.

    Science.gov (United States)

    Kay, Paul; Blackwell, Paul A; Boxall, Alistair B A

    2005-05-01

    The environment may be exposed to veterinary medicines administered to livestock due to the application of organic fertilisers to land. Slurry is often spread on to fields following the harvest of the previous crop. Despite recommendations to do so, the slurry may not be ploughed into the soil for some time. If precipitation occurs before incorporation then it is likely that the slurry and any antibiotic residues in the slurry will be transported towards surface waters in overland flow. This phenomenon has been investigated in a plot study and transport via 'tramlines' has been compared to that through crop stubble. Three veterinary antibiotics, from the tetracycline, sulphonamide and macrolide groups, were applied to the plots in pig slurry. Twenty four hours after the application the plots were irrigated. Following this the plots received natural rainfall. Sulphachloropyridazine was detected in runoff from the tramline plot at a peak concentration of 703.2 microgl(-1) and oxytetracycline at 71.7 microgl(-1). Peak concentrations from the plot that did not contain a tramline were lower at 415.5 and 32 microgl(-1), respectively. In contrast, tylosin was not detected at all. Mass losses of the compounds were also greater from the tramline plot due to greater runoff generation. These did not exceed 0.42% for sulphachloropyridazine and 0.07% for oxytetracycline however.

  15. Molecular dynamics simulations of melting behavior of alkane as phase change materials slurry

    International Nuclear Information System (INIS)

    Rao Zhonghao; Wang Shuangfeng; Wu Maochun; Zhang Yanlai; Li Fuhuo

    2012-01-01

    Highlights: ► The melting behavior of phase change materials slurry was investigated by molecular dynamics simulation method. ► Four different PCM slurry systems including pure water and water/n-nonadecane composite were constructed. ► Amorphous structure and periodic boundary conditions were used in the molecular dynamics simulations. ► The simulated melting temperatures are very close to the published experimental values. - Abstract: The alkane based phase change materials slurry, with high latent heat storage capacity, is effective to enhance the heat transfer rate of traditional fluid. In this paper, the melting behavior of composite phase change materials slurry which consists of n-nonadecane and water was investigated by using molecular dynamics simulation. Four different systems including pure water and water/n-nonadecane composite were constructed with amorphous structure and periodic boundary conditions. The results showed that the simulated density and melting temperature were very close to the published experimental values. Mixing the n-nonadecane into water decreased the mobility but increased the energy storage capacity of composite systems. To describe the melting behavior of alkane based phase change materials slurry on molecular or atomic scale, molecular dynamics simulation is an effective method.

  16. Swine slurry application and soil management on double-cropped oat/maize

    Directory of Open Access Journals (Sweden)

    Marlo Adriano Bison Pinto

    2014-06-01

    Full Text Available The swine production in southern Brazil is concentrated in small farms that use residues as a nutrient source for crops of economic interest. This study aimed to evaluate the use of swine slurry associated with tillage systems on double-cropped oat/maize. The experiment was carried out in the 2009/2010 and 2010/2011 cropping seasons, in Taquaruçu do Sul, Rio Grande do Sul State, Brazil. The experimental design was randomized blocks in a factorial scheme, with four replications. Treatments consisted of the interaction of four swine slurry doses (no swine slurry, 20 m3 ha-1, 40 m3 ha-1 and 80 m3 ha-1 and mineral fertilization, in three tillage systems (no-tillage, chiseling and chiseling + disking. The swine slurry application on doublecropped oat/maize increased the dry matter and grain yield. The 80 m3 ha-1 dose provided a response statistically similar to the mineral fertilization recommended for maize. The interaction between the 80 m3 ha-1 dose and the immediate incorporation of slurry into the soil reduced N losses by ammonia volatilization, promoting a significant increase in maize grain yield, when grown on a clayish soil.

  17. Evaluation and testing of metering pumps for high-level nuclear waste slurries

    International Nuclear Information System (INIS)

    Peterson, M.E.; Perez, J.M. Jr.; Blair, H.T.

    1986-06-01

    The metering pump system that delivers high-level liquid wastes (HLLW) slurry to a melter is an integral subsystem of the vitrification process. The process of selecting a pump for this application began with a technical review of pumps typically used for slurry applications. The design and operating characteristics of numerous pumps were evaluated against established criteria. Two pumps, an air-displacement slurry (ADS) pump and an air-lift pump, were selected for further development. In the development activity, from FY 1983 to FY 1985, the two pumps were subjected to long-term tests using simulated melter feed slurries to evaluate the pumps' performances. Throughout this period, the designs of both pumps were modified to better adapt them for this application. Final reference designs were developed for both the air-displacement slurry pump and the air-lift pump. Successful operation of the final reference designs has demonstrated the feasibility of both pumps. A fully remote design of the ADS pump has been developed and is currently undergoing testing at the West Valley Demonstration Project. Five designs of the ADS pump were tested and evaluated. The initial four designs proved the operating concept of the ADS pump. Weaknesses in the ADS pump system were identified and eliminated in later designs. A full-scale air-lift pump was designed and tested as a final demonstration of the air-lift pump's capabilities

  18. Nutrient Status and Contamination Risks from Digested Pig Slurry Applied on a Vegetable Crops Field

    Directory of Open Access Journals (Sweden)

    Shaohui Zhang

    2016-04-01

    Full Text Available The effects of applied digested pig slurry on a vegetable crops field were studied. The study included a 3-year investigation on nutrient characteristics, heavy metals contamination and hygienic risks of a vegetable crops field in Wuhan, China. The results showed that, after anaerobic digestion, abundant N, P and K remained in the digested pig slurry while fecal coliforms, ascaris eggs, schistosoma eggs and hookworm eggs were highly reduced. High Cr, Zn and Cu contents in the digested pig slurry were found in spring. Digested pig slurry application to the vegetable crops field led to improved soil fertility. Plant-available P in the fertilized soils increased due to considerable increase in total P content and decrease in low-availability P fraction. The As content in the fertilized soils increased slightly but significantly (p = 0.003 compared with control. The Hg, Zn, Cr, Cd, Pb, and Cu contents in the fertilized soils did not exceed the maximum permissible contents for vegetable crops soils in China. However, high Zn accumulation should be of concern due to repeated applications of digested pig slurry. No fecal coliforms, ascaris eggs, schistosoma eggs or hookworm eggs were detected in the fertilized soils.

  19. Enhanced acetone-butanol-ethanol production from lignocellulosic hydrolysates by using starchy slurry as supplement.

    Science.gov (United States)

    Yang, Ming; Kuittinen, Suvi; Vepsäläinen, Jouko; Zhang, Junhua; Pappinen, Ari

    2017-11-01

    This study aims to improve acetone-butanol-ethanol production from the hydrolysates of lignocellulosic material by supplementing starchy slurry as nutrients. In the fermentations of glucose, xylose and the hydrolysates of Salix schwerinii, the normal supplements such as buffer, minerals, and vitamins solutions were replaced with the barley starchy slurry. The ABE production was increased from 0.86 to 14.7g/L by supplementation of starchy slurry in the fermentation of xylose and the utilization of xylose increased from 29% to 81%. In the fermentations of hemicellulosic and enzymatic hydrolysates from S. schwerinii, the ABE yields were increased from 0 and 0.26 to 0.35 and 0.33g/g sugars, respectively. The results suggested that the starchy slurry supplied the essential nutrients for ABE fermentation. The starchy slurry as supplement could improve the ABE production from both hemicellulosic and cellulosic hydrolysate of lignocelluloses, and it is particularly helpful for enhancing the utilization of xylose from hemicelluloses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Physio-Microstructural Properties of Aerated Cement Slurry for Lightweight Structures

    Science.gov (United States)

    Salem, Talal; Hamadna, Sameer; Darsanasiri, A. G. N. D.; Soroushian, Parviz; Balchandra, Anagi; Al-Chaar, Ghassan

    2018-01-01

    Cementitious composites, including ferrocement and continuous fiber reinforced cement, are increasingly considered for building construction and repair. One alternative in processing of these composites is to infiltrate the reinforcement (continuous fibers or chicken mesh) with a flowable cementitious slurry. The relatively high density of cementitious binders, when compared with polymeric binders, are a setback in efforts to introduce cementitious composites as lower-cost, fire-resistant, and durable alternatives to polymer composites. Aeration of the slurry is an effective means of reducing the density of cementitious composites. This approach, however, compromises the mechanical properties of cementitious binders. An experimental program was undertaken in order to assess the potential for production of aerated slurry with a desired balance of density, mechanical performance, and barrier qualities. The potential for nondestructive monitoring of strength development in aerated cementitious slurry was also investigated. This research produced aerated slurries with densities as low as 0.9 g/cm3 with viable mechanical and barrier qualities for production of composites. The microstructure of these composites was also investigated. PMID:29649163

  1. 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

  2. Reducing Pumping Power in Hydronic Heating and Cooling Systems with Microencapsulated Phase Change Material Slurries

    Science.gov (United States)

    Karas, Kristoffer Jason

    Phase change materials (PCMs) are being used increasingly in a variety of thermal transfer and thermal storage applications. This thesis presents the results of a laboratory study into the feasibility of improving the performance of hydronic heating and cooling systems by adding microcapsules filled with a PCM to the water used as heat transport media in these systems. Microencapsulated PCMs (MPCMs) increase the heat carrying capacity of heat transport liquids by absorbing or releasing heat at a constant temperature through a change of phase. Three sequences of tests and their results are presented: 1) Thermal cycling tests conducted to determine the melting temperatures and extent of supercooling associated with the MPCMs tested. 2) Hydronic performance tests in which MPCM slurries were pumped through a fin-and-tube, air-to-liquid heat exchanger and their thermal transfer performance compared against that of ordinary water. 3) Mechanical stability tests in which MPCM slurries were pumped in a continuous loop in order to gauge the extent of rupture due to pumping. It is shown that slurries consisting of water and MPCMs ˜ 14-24 mum in diameter improve thermal performance and offer the potential for power savings in the form of reduced pumping requirements. In addition, it is shown that while slurries of MPCMs 2-5 mum in diameter appear to exhibit better mechanical stability than slurries of larger diameter MPCMs, the smaller MPCMs appear to reduce the thermal performance of air-to-liquid heat exchangers.

  3. The erosion performance of cold spray deposited metal matrix composite coatings with subsequent friction stir processing

    Energy Technology Data Exchange (ETDEWEB)

    Peat, Tom, E-mail: tompeat12@gmail.com [Department of Mechanical & Aerospace Engineering, University of Strathclyde, James Weir Building, 75 Montrose Street, Glasgow G1 1XJ (United Kingdom); Galloway, Alexander; Toumpis, Athanasios [Department of Mechanical & Aerospace Engineering, University of Strathclyde, James Weir Building, 75 Montrose Street, Glasgow G1 1XJ (United Kingdom); McNutt, Philip [TWI Ltd., Granta Park, Cambridge CB21 6AL (United Kingdom); Iqbal, Naveed [TWI Technology Centre, Wallis Way, Catcliff, Rotherham, S60 5TZ (United Kingdom)

    2017-02-28

    Highlights: • WC-CoCr, Cr{sub 3}C{sub 2}-NiCr and Al{sub 2}O{sub 3} coatings were cold spray deposited on AA5083 and friction stir processed. • The SprayStirred WC-CoCr demonstrated a hardness increase of 100% over the cold sprayed coating. • As-deposited and SprayStirred coatings were examined under slurry erosion test conditions. • Mass and volume loss was measured following 20-min exposure to the slurry. • The WC-CoCr and Al2O3 demonstrated a reduction in volume loss of approx. 40% over the cold sprayed coating. - Abstract: This study forms an initial investigation into the development of SprayStir, an innovative processing technique for generating erosion resistant surface layers on a chosen substrate material. Tungsten carbide – cobalt chromium, chromium carbide – nickel chromium and aluminium oxide coatings were successfully cold spray deposited on AA5083 grade aluminium. In order to improve the deposition efficiency of the cold spray process, coatings were co-deposited with powdered AA5083 using a twin powder feed system that resulted in thick (>300 μm) composite coatings. The deposited coatings were subsequently friction stir processed to embed the particles in the substrate in order to generate a metal matrix composite (MMC) surface layer. The primary aim of this investigation was to examine the erosion performance of the SprayStirred surfaces and demonstrate the benefits of this novel process as a surface engineering technique. Volumetric analysis of the SprayStirred surfaces highlighted a drop of approx. 40% in the level of material loss when compared with the cold spray deposited coating prior to friction stir processing. Micro-hardness testing revealed that in the case of WC-CoCr reinforced coating, the hardness of the SprayStirred material exhibits an increase of approx. 540% over the unaltered substrate and 120% over the as-deposited composite coating. Microstructural examination demonstrated that the increase in the hardness of the

  4. Microstructure and erosive wear behaviors of Ti6Al4V alloy treated by plasma Ni alloying

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z.X.; Wu, H.R.; Shan, X.L.; Lin, N.M.; He, Z.Y., E-mail: tyuthzy@126.com; Liu, X.P.

    2016-12-01

    Graphical abstract: The Ni modified layers were prepared on the surface of Ti6Al4V substrate by the plasma surface alloying technique. The surface and cross-section morphology, element concentration and phase composition were investigated by thermal field emission scanning electron microscopy (SEM), and glow discharge optical emission spectroscopy (GDOES), X-ray diffraction (XRD), respectively. The cross-section nano-scale hardness of Ni modified layer was measured by nano indenter. The results showed that Ni modified layers exhibited triple layers structure and continuous gradient distribution of the concentration. From the surface to the matrix, they were 2 μm Ni deposition layer, 8 μm Ni-rich alloying layer including the phases of Ni{sub 3}Ti, NiTi, Ti{sub 2}Ni, AlNi{sub 3} and 24 μm Ni-poor alloying layer forming the solid solution of nickel. With increasing of the thickness of Ni modified layer, the microhardness increased first, reached the climax, then gradient decreased. The erosion tests were performed on the surface of the untreated and treated Ti6Al4V sample using MSE (Micro-slurry-jet Erosion) method. The experiment results showed that the wear rate of every layer showed different value, and the Ni-rich alloying layer was the lowest. The strengthening mechanism of Ni modified layer was also discussed. - Highlights: • The Ni modified layers were prepared by the plasma surface alloying technique. • Triple layers structure was prepared. • Using Micro-slurry-jet Erosion method. • The erosion rate of Ni modified layer experienced the process of descending first and then ascending. • Improvement of erosion resistance performance of Ni-rich alloying layer was prominent. The wear mechanism of Ni modified layer showed micro-cutting wearing. - Abstract: The Ni modified layers were prepared on the surface of Ti6Al4V substrate by the plasma surface alloying technique. The surface and cross-section morphology, element concentration and phase composition

  5. Mapping monthly rainfall erosivity in Europe.

    Science.gov (United States)

    Ballabio, Cristiano; Borrelli, Pasquale; Spinoni, Jonathan; Meusburger, Katrin; Michaelides, Silas; Beguería, Santiago; Klik, Andreas; Petan, Sašo; Janeček, Miloslav; Olsen, Preben; Aalto, Juha; Lakatos, Mónika; Rymszewicz, Anna; Dumitrescu, Alexandru; Tadić, Melita Perčec; Diodato, Nazzareno; Kostalova, Julia; Rousseva, Svetla; Banasik, Kazimierz; Alewell, Christine; Panagos, Panos

    2017-02-01

    Rainfall erosivity as a dynamic factor of soil loss by water erosion is modelled intra-annually for the first time at European scale. The development of Rainfall Erosivity Database at European Scale (REDES) and its 2015 update with the extension to monthly component allowed to develop monthly and seasonal R-factor maps and assess rainfall erosivity both spatially and temporally. During winter months, significant rainfall erosivity is present only in part of the Mediterranean countries. A sudden increase of erosivity occurs in major part of European Union (except Mediterranean basin, western part of Britain and Ireland) in May and the highest values are registered during summer months. Starting from September, R-factor has a decreasing trend. The mean rainfall erosivity in summer is almost 4 times higher (315MJmmha -1 h -1 ) compared to winter (87MJmmha -1 h -1 ). The Cubist model has been selected among various statistical models to perform the spatial interpolation due to its excellent performance, ability to model non-linearity and interpretability. The monthly prediction is an order more difficult than the annual one as it is limited by the number of covariates and, for consistency, the sum of all months has to be close to annual erosivity. The performance of the Cubist models proved to be generally high, resulting in R 2 values between 0.40 and 0.64 in cross-validation. The obtained months show an increasing trend of erosivity occurring from winter to summer starting from western to Eastern Europe. The maps also show a clear delineation of areas with different erosivity seasonal patterns, whose spatial outline was evidenced by cluster analysis. The monthly erosivity maps can be used to develop composite indicators that map both intra-annual variability and concentration of erosive events. Consequently, spatio-temporal mapping of rainfall erosivity permits to identify the months and the areas with highest risk of soil loss where conservation measures should be

  6. 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.

  7. The antifungal efficiency of carbide lime slurry compared with the commercial lime efficiency

    Science.gov (United States)

    Strigac, J.; Mikusinec, J.; Strigacova, J.; Stevulova, N.

    2017-10-01

    The article deals with studying the antifungal efficiency of carbide lime slurry compared to industrially manufactured commercial lime. Antifungal efficiency expressed as mould proofness properties was tested on the fungi using the procedure given in standard CSN 72 4310. A mixture of fungi Aspergillus niger, Chaetomium globosum, Penicillium funiculosum, Paecilomyces variotii and Gliocladium virens was utilized for testing. The scale for evaluating mould proofness properties according to CSN 72 4310 is from 0 to 5 in degree of fungi growth, where 0 means that no fungi growth occurs and the building products and materials possess fungistatic properties. The study confirms the fungistatic propeties of carbide lime slurry as well as industrially manufactured commercial lime. However, carbide lime slurry and industrially manufactured commercial lime possess no fungicidal effect.

  8. Heat transfer enhanced microwave process for stabilization of liquid radioactive waste slurry. Final report

    International Nuclear Information System (INIS)

    White, T.L.

    1995-01-01

    The objectve of this CRADA is to combine a polymer process for encapsulation of liquid radioactive waste slurry developed by Monolith Technology, Inc. (MTI), with an in-drum microwave process for drying radioactive wastes developed by Oak Ridge National Laboratory (ORNL), for the purpose of achieving a fast, cost-effectve commercial process for solidification of liquid radioactive waste slurry. Tests performed so far show a four-fold increase in process throughput due to the direct microwave heating of the polymer/slurry mixture, compared to conventional edge-heating of the mixer. We measured a steady-state throughput of 33 ml/min for 1.4 kW of absorbed microwave power. The final waste form is a solid monolith with no free liquids and no free particulates

  9. A site-specific slurry application technique on grassland and on arable crops.

    Science.gov (United States)

    Schellberg, Jürgen; Lock, Reiner

    2009-01-01

    There is evidence that unequal slurry application on agricultural land contributes to N losses to the environment. Heterogeneity within fields demands adequate response by means of variable rate application. A technique is presented which allows site-specific application of slurry on grassland and arable land based on pre-defined application maps. The system contains a valve controlling flow rate by an on-board PC. During operation, flow rate is measured and scaled against set point values given in the application map together with the geographic position of the site. The systems worked sufficiently precise at a flow rate between 0 and 25 l s(-1) and an offset of actual slurry flow from set point values between 0.33 and 0.67 l s(-1). Long-term experimentation is required to test if site-specific application de facto reduces N surplus within fields and so significantly contributes to the unloading of N in agricultural areas.

  10. Design and performance of feed-delivery systems for simulated radioactive waste slurries

    International Nuclear Information System (INIS)

    Perez, J.M. Jr.

    1983-02-01

    Processes for vitrifying simulated high-level radioactive waste have been developed at the Pacific Northwest Laboratory (PNL) over the last several years. Paralleling this effort, several feed systems used to deliver the simulated waste slurry to the melter have been tested. Because there had been little industrial experience in delivering abrasive slurries at feed rates of less than 10 L/min, early experience helped direct the design of more-dependable systems. Also, as feed delivery requirements changed, the feed system was modified to meet these new requirements. The various feed systems discussed in this document are part of this evolutionary process, so they have not been ranked against each other. The four slurry feed systems discussed are: (1) vertical-cantilevered centrifugal pump system; (2) airlift feed systems; (3) pressurized-loop systems; and (4) positive-displacement pump system. 20 figures, 11 tables

  11. Sustainable use of pig slurry, with and without treatment, as an amendment organic in almond crop

    International Nuclear Information System (INIS)

    Dominguez Oliver, S. G.; Faz Cano, A.

    2009-01-01

    This study consists in the use of different forms of slurry, as an organic fertilizer, on almond trees located in La Aljorra (Cartegena, Murcia). The slurry used comes from a farm near the area of study, which has a treatment system composed by tree parts: a phase separator, a bioreactor and 5 constructed wetlands of vertical flow. Different phases of slurry are obtained from each part of the system. The results show the reduction of most of the parameters lime salinity, BOD 5 QOD, nitrate, etc. The use of these effluents as an organic amend in different doses, supposes a sustainable way of management of these residues; at the same time it improves the soil properties and the agronomic quality of the almond tree crop. (Author) 4 refs.

  12. Design and Operation of the World's First Long Distance Bauxite Slurry Pipeline

    Science.gov (United States)

    Gandhi, Ramesh; Weston, Mike; Talavera, Maru; Brittes, Geraldo Pereira; Barbosa, Eder

    Mineracão Bauxita Paragominas (MBP) is the first long distance slurry pipeline transporting bauxite slurry. Bauxite had developed a reputation for being difficult to hydraulically transport using long distance pipelines. This myth has now been proven wrong. The 245-km- long, 13.5 MTPY capacity MBP pipeline was designed and commissioned by PSI for CVRD. The pipeline is located in the State of Para, Brazil. The Miltonia bauxite mine is in a remote location with no other efficient means of transport. The bauxite slurry is delivered to Alunorte Alumina refinery located near Barcarena. This first of its kind pipeline required significant development work in order to assure technical and economic feasibility. This paper describes the technical aspects of design of the pipeline. It also summarizes the operating experience gained during the first year of operation.

  13. Natural convection heat transfer enhancement using Microencapsulated Phase-Change-Material slurries

    International Nuclear Information System (INIS)

    Kubo, Shinji; Akino, Norio; Tanaka, Amane; Nakano, Fumihiko; Nagashima, Akira.

    1997-01-01

    The present study investigates natural convection heat transfer from a heated cylinder cooled by a water slurry of Microencapsulated Phase Change Material (MCPCM). A normal paraffin hydrocarbon with carbon number of 18 and melting point of 27.9degC, is microencapsulated by Melamine resin into particles of which average diameter is 9.5μm and specific weight is same as water. The slurry of the MCPCM and water is put into a test apparatus, which is a rectangular enclosure with a heated horizontal cylinder. As the concentrations of PCM in the slurry are changed in 1,3 and 5%, the heat transfer coefficients of the cylinder are larger than that of water as working fluid, by 3,20 and 35% enhancements respectively. (author)

  14. Spray polyurea coatings as containment liners in coal slurry storage ponds

    Energy Technology Data Exchange (ETDEWEB)

    Darden, J.W.; Loomis, R.; Roehm, F.T. [Willamette Valley Co., Eugene, OR (United States)

    1996-12-31

    The Southern California Edison (SCE) Mohave Generating Station was built in the early 1970`s in response to the shortage of oil due to the OPEC boycott. Coal/water slurry from the Black Mesa Pipeline is used to generate energy at the plant. Eight storage ponds, each about 175,000 square feet, were built in the mid to late 1970`s to insure a constant supply of slurry to feed the generating units. This paper describes the application of POLYQuik{trademark} P400 spray polyurea coating to the Marcona Pond, a coal slurry storage area at Southern California Edison`s Mohave Generating Station. The coating forms an impermeable barrier to prevent water loss and contamination of subgrade soils. The use of these coatings reduces facility downtime and liner replacement costs, offering a cost savings over the life of the pond.

  15. Lithosphere erosion atop mantle plumes

    Science.gov (United States)

    Agrusta, R.; Arcay, D.; Tommasi, A.

    2012-12-01

    Mantle plumes are traditionally proposed to play an important role in lithosphere erosion. Seismic images beneath Hawaii and Cape Verde show a lithosphere-asthenosphere-boundary (LAB) up to 50 km shallower than the surroundings. However, numerical models show that unless the plate is stationary the thermo-mechanical erosion of the lithosphere does not exceed 30 km. We use 2D petrological-thermo-mechanical numerical models based on a finite-difference method on a staggered grid and marker in cell method to study the role of partial melting on the plume-lithosphere interaction. A homogeneous peridotite composition with a Newtonian temperature- and pressure-dependent viscosity is used to simulate both the plate and the convective mantle. A constant velocity, ranging from 5 to 12.5 cm/yr, is imposed at the top of the plate. Plumes are created by imposing a thermal anomaly of 150 to 350 K on a 50 km wide domain at the base of the model (700 km depth); the plate right above the thermal anomaly is 40 Myr old. Partial melting is modeled using batch-melting solidus and liquidus in anhydrous conditions. We model the progressive depletion of peridotite and its effect on partial melting by assuming that the melting degree only strictly increases through time. Melt is accumulated until a porosity threshold is reached and the melt in excess is then extracted. The rheology of the partially molten peridotite is determined using viscous constitutive relationship based on a contiguity model, which enables to take into account the effects of grain-scale melt distribution. Above a threshold of 1%, melt is instantaneously extracted. The density varies as a function of partial melting degree and extraction. Besides, we analyze the kinematics of the plume as it impacts a moving plate, the dynamics of time-dependent small-scale convection (SSC) instabilities developing in the low-viscosity layer formed by spreading of hot plume material at the lithosphere base, and the resulting thermal

  16. X-ray diagnosis of erosive gastritis

    International Nuclear Information System (INIS)

    Taskov, A.; Krastin, A.

    1993-01-01

    A series of 602 patients are studied according to a standard protocol including double contrast examination, taking films with dosed compression and complete filling (accordingly 3+3+1 radiographs). A barium suspension at concentration 200.0 BaSO 4 in 100 ml water is used as a positive contrast medium, and effervescent powder or pills - as a negative contrast. Erosive gastritis is diagnosed in 48 patients (7.9%) of which 38 present complete erosions (79.2%), 6 (12.6%) - incomplete, and 4 (8.3%) - mixed erosions. In 35 cases (72.9%) erosions are differentiated in double-contrast films, while in 21 (43.8%) - in those with compression. The advantage of the double contrast technique consists in visualization of erosions of the body of the stomach and discovering of incomplete erosions. In 483 patients a comparative assessment is done of the X-ray and endoscopic findings. There are recorded 5 false-positive and 25 false-negative radiological results. The sensitivity of the X-ray study in terms of erosive gastritis amounts to 59.7%. 15 refs., 4 figs. (orig.)

  17. Erosion and stability of a mine soil

    International Nuclear Information System (INIS)

    Wu, T.H.; Stadler, A.T.; Low, C.

    1996-01-01

    Mine soils developed from mine spoils commonly have a wide range of particle size. The slopes of old spoil piles usually are marked by gullies due to years of uncontrolled erosion. These characteristics raise questions about applicability of available theories and models for estimating runoff and erosion. An investigation was made to determine whether available erosion models can work for mine soils and can account for gully erosion. The investigation at an abandoned surface mine consisted of measurement of soil and sediment properties, measurement of runoff and erosion, observations of armor by rock fragments on gully floor, and calculations with available theories of sediment transport and slope stability. The results at this site suggest that (1) predictions with the ANSWERS model have about the same accuracy as those made for agricultural lands; (2) armor provided by rock fragments are temporary as they are periodically removed by debris flows; (3) detachment by rainfall impact is the primary cause of erosion on short steep slopes; and (4) a simplified method can be used for estimating erosion on such slopes

  18. Soft drinks and in vitro dental erosion.

    Science.gov (United States)

    Gravelle, Brent L; Hagen Ii, Ted W; Mayhew, Susan L; Crumpton, Brooks; Sanders, Tyler; Horne, Victoria

    2015-01-01

    The purpose of this investigation was to determine to what extent the in vitro exposure of healthy teeth to various commonly consumed carbonated soft drinks may precipitate dental erosion. Forty-two healthy, extracted, previously unerupted human molars were weighed prior to, during, and after suspension in various sugared and diet or zero-calorie carbonated beverages for 20 days; the specimens were stored at room temperature while being stirred at 275 rpm. The percentage decrease in tooth weight from before to after exposure represented the weight loss due to enamel erosion; values in the experimental groups varied from 3.22% to 44.52% after 20 days' exposure. Data were subjected to analysis of variance and post hoc Scheffe testing at a level of α = 0.05. Nonsugared drinks (diet and zero-calorie) as a whole were more erosive than sugared beverages. A significant positive correlation was found between the amount of titratable acid and percentage of tooth erosion, while a significant negative correlation was revealed between the beverage pH and percentage of tooth erosion. No significant correlations were found between calcium or phosphate ion concentrations and the amount of erosion. It appears that enamel erosion is dependent on not only the beverage flow rate, pH, and amount of titratable acid, but also whether the soft drink is of the diet or zero-calorie variety, which reflects the type of artificial sweetener present.

  19. Synthesis gas solubility in Fischer-Tropsch slurry: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Chao, K.C.; Lin, H.M.

    1988-01-01

    The objective is to investigate the phase equilibrium behavior of synthesis gases and products in a Fischer-Tropsch slurry reactor. A semi-flow apparatus has been designed and constructed for this purpose. Measurements have been made for hydrogen, cabon monoxide, methane, ethane, ethylene, and carbon dioxide in a heavy n-paraffin at temperatures from 100 to 300)degree)C and pressures 10 to 50 atm. Three n-paraffin waxes: n-eicosane (n-C/sub 20/), n-octacosane )n-C/sub 28/), and n-hexatriacontane (n-C/sub 36/), were studied to model the industrial wax. Solubility of synthesis gas mixtures of H/sub 2/ and CO in n-C/sub 28/ was also determined at two temperatures (200 and 300)degree)C) for each of three gas compositions (40.01, 50.01, and 66.64 mol%) of hydrogen). Measurements were extended to investigate the gas solubility in two industrial Fischer-Tropsch waxes: Mobilwax and SASOL wax. Observed solubility increases in the order: H/sub 2/, CO, CH/sub 4/, CO/sub 2/, C/sub 2/H/sub 4/, C/sub 2/H/sub 6/, at a given temperature pressure, and in the same solvent. Solubility increases with increasing pressure for all the gases. Lighter gases H/sub 2/ and CO show increased solubility with increasing temperature, while the heavier gases CO/sub 2/, ethane, and ethylene show decreased solubility with increasing temperature. The solubility of methane, the intermediate gas, changes little with temperature, and shows a shallow minimum at about 200)degrees)C or somewhat above. Henry's constant and partial molal volume of the gas solute at infinite dilution are determinedfrom the gas solubility data. A correlation is developed from the experimental data in the form on an equation of state. A computer program has been prepared to implement the correlation. 19 refs., 66 figs., 39 tabs.

  20. Estimating surface soil erosion losses and mapping erosion risk for Yusufeli micro-catchment (Artvin

    Directory of Open Access Journals (Sweden)

    Mustafa Tüfekçioğlu

    2016-10-01

    Full Text Available Sheet erosion, one of the most important types of water erosion, takes place on the top soil as tiny soil layer movement that affects lake and stream ecosystem. This type of erosion is very important because the productive soil layer on the top soil can be lost in a very short period of time. The goal of this study was to quantify the amount of surface (sheet and rill soil erosion, and to identify areas under high erosion risk within the study area at Yusufeli province in Artvin by using RUSLE erosion methodology. As a result of the study it was found that the average annual potential soil loss by surface erosion was 3.6 ton ha-1yr-1. Additionally, the maps produced and conclusions reached by the study revealed that the areas of high erosion risk were identified spatially and measures to control erosion on some of these high risk areas can be possible with appropriate erosion control techniques.

  1. Erosion by rain in the western Congo

    International Nuclear Information System (INIS)

    Ploey, J. de

    1967-01-01

    Vast expanses of the western part of central and southern Africa are covered with uniform, sandy formations of the Kalahari type. The topography of these areas and their present morphological characteristics are mainly the result of erosion by rain. Information on the hydrology of the surface waters in these areas is fairly limited and is insufficient to permit any conclusions regarding the way in which erosion by rain takes place. To obtain a better understanding of these phenomena, the author devised a series of experiments based on the use of 46 Sc-labelled radioactive sand. These experiments began at the beginning of the 1964/65 rainy season and are continuing. The experimental plot corresponds to convex and rectilinear portions of a hillside with a slope varying between 0 and 12 degrees. The vegetation consists of grassy savannah of substeppe appearance and secondary forests. Series of labelled samples were placed successively on the surface of the experimental plot and the erosive effect of rain was determined by measuring the residual concentrations after rainfall. Some samples were placed below a shield so as to eliminate the effects of splash and reveal the part played by runoff. Radiographic films were used to study the dispersion of labelled particles in the surrounding area. This radiographic method made it possible to determine the scale of erosion by splash for different rainfall conditions. The erosion diagrams obtained from these experiments show the correlations that exist between the intensity and duration of the rainfall and the erosion of the soil. Examination of the erosion diagrams and the shielded samples and analysis of the radiographs showed that erosion by rain on Kalahari ground covered with substeppe savannah is caused mainly by splash erosion and by dispersed, intermittent runoff. Sheet wash plays no part if the slope is less than 12 degrees. (author) [fr

  2. Carbon mineralization in mine tailing ponds amended with pig slurries and marble wastes

    Directory of Open Access Journals (Sweden)

    Raul Zornoza

    2012-07-01

    Full Text Available Effective application of organic residues to reclaim soils requires the optimization of the waste management to minimize CO2 emissions and optimize soil C sequestration efficiency. In this study, the short-term effects of pig slurry amendment alone and together with marble waste on organic matter mineralization in two tailing ponds from Cartagena-La Unión Mining District (SE Spain were investigated in a field remediation experiment. The treatments were: marble waste (MW, pig slurry (PS, marble waste + pig slurry (MW+PS, and control. Soil carbon mineralization was determined using a static chamber method with alkali absorption during 70 days. Soil respiration rates in all plots were higher the first days of the experiment owing to higher soil moisture and higher mean air temperature. MW plots followed the same pattern than control plots, with similar respiration rates. The addition of pig slurry caused a significant increase in the respiration rates, although in MW+PS plots, respiration rates were lower than in PS plots. The cumulative quantities of C-CO2 evolved from the pig slurry mineralization were fitted to a first-order kinetic model explaining 90% of the data. This model implies the presence of only one mineralisable pool (C0. The values of the index C0*constant rate/added C were similar for PS plots in both tailing ponds, but lower in the MW+PS treatment, suggesting that the application of marble reduces the degradability of the organic compounds present in the pig slurry. Thus, the application of marble wastes contributes to slow down the loss of organic matter by mineralization.

  3. 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.

  4. Yield Stress Reduction of Radioactive Waste Slurries by Addition of Surfactants

    International Nuclear Information System (INIS)

    MICHAEL, STONE

    2005-01-01

    The Savannah River Site (SRS) and Hanford site are in the process of stabilizing millions of gallons of radioactive waste slurries remaining from production of nuclear materials for the Department of Energy (DOE). The Defense Waste Processing Facility (DWPF) at SRS is currently vitrifying the waste in borosilicate glass while the facilities at the Hanford site are in the design/construction phase. Both processes utilize slurry-fed joule heated melters to vitrify the waste slurries. The rheological properties of the waste slurries limit the total solids content that can be processed by the remote equipment during the pretreatment and melter feed processes. The use of a surface active agent, or surfactant, to increase the solids loading that can be fed to the melters would increase melt rate by reducing the heat load on the melter required to evaporate the water in the feed. The waste slurries are non-Newtonian fluids with rheological properties that were modeled using the Bingham Plastic mod el (this model is typically used by SRNL when studying the DWPF process1).The results illustrate that altering the surface chemistry of the particulates in the waste slurries can lead to a reduction in the yield stress. Dolapix CE64 is an effective surfactant over a wide range of pH values and was effective for all simulants tested. The effectiveness of the additive increased in DWPF simulants as the concentration of the additive was increased. No maxi main effectiveness was observed. Particle size measurements indicate that the additive acted as a flocculant in the DWPF samples and as a dispersant in the RPP samples

  5. Slurry Ice as a Cooling System on 30 GT Fishing Vessel

    Directory of Open Access Journals (Sweden)

    Alam Baheramsyah

    2017-06-01

    Full Text Available Indonesia is the largest archipelago country in the world that has a sea area that is very spacious. Indonesian sea area is 5.8 million square kilometers and a coastline of 95 181 km has huge potential in the fisheries sector. In line with the need to further improve on the quality of the fish catch. One way to preserve fish is to use a slurry of ice. Slurry ice proved more effective preserving fishery products instead of using ice cubes. Ice slurry cooling system was designed and applied to the fishing vessel 30 GT. The cooling system uses a simple vapor compression system consists of five major components consisting of evaporator, condenser, compressor, and two pumps.In designing this system determined the type of refrigerant used in advance which type of refrigerant R-507a. Then do the design or selection of its main components. The design is only done on the evaporator. As for the other major components such as condensers, compressors, and pumps election in accordance with the specification of the power needed. After that dialakukan depiction of each system component. Then subsequently designing the laying of ice slurry cooling system components on a fishing vessel 30 GT.            Through calculations using simple thermodynamic equations obtained cooling load on this system amounted to 32.06 kW. Condenser with a power of 40 kW. Compressor with power 12 kW. Pump with capacity 10 m3 / h. With memepertimbangkan space left on the ship in the ice slurry system design on the main deck of the ship to the efficient use of space on board. The power requirements of the generator vessel increases due to the addition of ice slurry system components therefore do replacement generator into the generator with a power of 100 kW and penambahn fuel tank to 6,000 L.

  6. Liquid CO2/Coal Slurry for Feeding Low Rank Coal to Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Marasigan, Jose [Electric Power Research Institute, Inc., Palo Alto, CA (United States); Goldstein, Harvey [Electric Power Research Institute, Inc., Palo Alto, CA (United States); Dooher, John [Electric Power Research Institute, Inc., Palo Alto, CA (United States)

    2013-09-30

    This study investigates the practicality of using a liquid CO2/coal slurry preparation and feed system for the E-Gas™ gasifier in an integrated gasification combined cycle (IGCC) electric power generation plant configuration. Liquid CO2 has several property differences from water that make it attractive for the coal slurries used in coal gasification-based power plants. First, the viscosity of liquid CO2 is much lower than water. This means it should take less energy to pump liquid CO2 through a pipe compared to water. This also means that a higher solids concentration can be fed to the gasifier, which should decrease the heat requirement needed to vaporize the slurry. Second, the heat of vaporization of liquid CO2 is about 80% lower than water. This means that less heat from the gasification reactions is needed to vaporize the slurry. This should result in less oxygen needed to achieve a given gasifier temperature. And third, the surface tension of liquid CO2 is about 2 orders of magnitude lower than water, which should result in finer atomization of the liquid CO2 slurry, faster reaction times between the oxygen and coal particles, and better carbon conversion at the same gasifier temperature. EPRI and others have recognized the potential that liquid CO2 has in improving the performance of an IGCC plant and have previously conducted systemslevel analyses to evaluate this concept. These past studies have shown that a significant increase in IGCC performance can be achieved with liquid CO2 over water with certain gasifiers. Although these previous analyses had produced some positive results, they were still based on various assumptions for liquid CO2/coal slurry properties.

  7. Simulation of Reynolds number influence on heat exchange in turbulent flow of medium slurry

    Science.gov (United States)

    Bartosik, A.

    2016-10-01

    The paper deals with the numerical simulation of mass and heat exchange in turbulent flow of solid-liquid mixture in the range of averaged solid particle diameter from 0.10mm to 0.80mm, named further as the medium slurry. Physical model assumes that dispersed phase is fully suspended and a turbulent flow is hydro-dynamically, and thermally developed in a straight horizontal pipeline. Taking into account the aforementioned assumptions the slurry is treated as a single-phase flow with increased density, while viscosity is equals to a carrier liquid viscosity. The mathematical model constitutes time averaged momentum equation in which the turbulent stress tensor was designated using a two-equation turbulence model, which makes use of the Boussinesq eddy-viscosity hypothesis. Turbulence damping function in the turbulence model was especially designed for the medium slurry. In addition, an energy equation has been used in which a convective term was determined from the energy balance acting on a unit pipe length, assuming linear changes of temperature in main flow direction. Finally, the mathematical model of non-isothermal medium slurry flow comprises four partial differential equations, namely momentum and energy equations, equations of kinetic energy of turbulence and its dissipation rate. Four partial differential equations were solved by a finite difference scheme using own computer code. The objective of the paper is to examine the influence of Reynolds number on temperature profiles and Nusselt number in turbulent flow of medium slurry in the range of solids concentration from 0% to 30% by volume. The effect of influential factors on heat transfer between the pipe and slurry is analysed. The paper demonstrates substantial impact of Reynolds number and solids volume fraction on the Nusselt number. The results of numerical simulation are reviewed.

  8. Modelling the potential of slurry management technologies to reduce the constraints of environmental legislation on pig production

    DEFF Research Database (Denmark)

    Hutchings, Nicholas John; ten Hoeve, Marieke; Jensen, Rikke

    2013-01-01

    Limits on land applications of slurry nitrogen (N) and phosphorus (P) are used to restrict losses of nutrients caused by livestock production. Here, we used a model to assess technologies that enable a more even geographic distribution of slurry nutrients to land. Technologies included were screw...

  9. Electrochemistry of carbonaceous materials. 3. Reactivity of redox couples with coal slurries in 85% phosphoric acid media

    Energy Technology Data Exchange (ETDEWEB)

    Tomat, R.; Salmaso, R.; Zecchin, S. [CNR - Istituto di Polarografia ed Elettrochimica Preparativa, Padova (Italy)

    1994-02-01

    Sardinian subbituminous coal slurries were oxidized in 85% H{sub 3}PO{sub 4} by metal ions (Ce{sup 4+}, V{sup 5+}, V{sup 4+}, Mn{sup 3+} and Fe{sup 3+}) and the effects of metal ion concentration, coal content of slurry, coal particle size and temperature were examined. 19 refs., 3 figs., 2 tabs.

  10. An experimental investigation of the thermal/fluid properties of the nitrate to ammonia and ceramic (NAC) product slurry

    International Nuclear Information System (INIS)

    Muguercia, I.; Lagos, L.; Yang, G.; Li, W.; Ebadian, M.A.; Mattus, A.J.; Lee, D.D.; Walker, J.W.; Hunt, R.D.

    1994-01-01

    Recently, a new immobilization technique for LLW, the Nitrate to Ammonia and Ceramic (NAC) process, has been developed. Instead of mixing the liquid waste form directly with the cement to make concrete blocks, the NAC process eliminates the nitrate from the LLW by converting it to ammonia gas. Aluminum particles are used as a reductant to complete this conversion. The final product of the NAC process is gibbsite, which can be further sintered to a ceramic waste form. Experimental tests are conducted to measure the apparent viscosity, the pressure drop, and the heat transfer coefficient of the pipe flow of the Nitrate to Ammonia and Ceramic (NAC) process product slurry. The tests indicate that the NAC product slurry exhibits a typical pseudoplastic fluid behavior. The pressure drop in the pipe flow is a function of the Reynolds number and the slurry temperature. The results also indicate that at a low slurry temperature, the slurry is uniformly heated peripherally. At a high slurry temperature, however, the slurry may be thermally stratified. In a straight pipe, the Nusselt number is reduced as the slurry temperature increases

  11. Voluntary intake and digestibility by sheep of alfalfa ensiled at different moisture concentrations following fertilization with dairy slurry

    Science.gov (United States)

    Dairy slurry is used commonly as an animal-sourced fertilizer in agronomic production. However, residual effects of slurry application on intake and digestibility of alfalfa (Medicago sativa L.) silage from subsequent harvests are not well known. The objective of this study was to determine if mois...

  12. The Variation of Interface Formation with Slurry Viscosity Change in Side-By-Side Tape Casting

    DEFF Research Database (Denmark)

    Bulatova, Regina; Jabbari, Masoud; Andersen, Kjeld Bøhm

    Homogenous and flexible adjacently graded tapes were produced by casting the organic-based slurries simultaneously. To develop side-by-side tape casing (SBSTC), the material optimization, modernization of the doctor blade design, and parameters control of such processes as casting, drying, de......-bindering and sintering were studied. Solvent and binder concentrations were varied in order to optimize co-casting flow, as well as the drying and sintering shrinkage. Tapes were evaluated in terms of rheological behavior of the slurries, the green and sintered tape microstructure, the quality of the interface area...

  13. Slurry dispersion state as a parameter to control internal structure of alumina green compact

    Energy Technology Data Exchange (ETDEWEB)

    Saito, M.; Shui, A.; Tanaka, S.; Uchida, N.; Uematsu, K. [Nagaoka Univ. of Technology, Niigata (Japan)

    2002-07-01

    The dispersion state of slurry must be controlled to produce granules with appropriated properties for pressing. In this study dispersion state of alumina slurry is changed to form granules with different morphology, deformation property and packing density, and the influence on the internal structure of green compact are presented. Novel methods applying liquid immersion technique coupled with different type of microscopy were used to characterize the internal structures of green compacts. Two types of granules were obtained: dimpled, hard and dense granule, and spherical, soft and loose granule. The respective internal structures of green compacts were totally different. (orig.)

  14. Methanotrophs, methanogens and microbial community structure in livestock slurry surface crusts

    DEFF Research Database (Denmark)

    Duan, Y.F.; Abu Al-Soud, Waleed; Brejnrod, Asker Daniel

    2014-01-01

    , and Methylosarcina of Type I, and Methylocystis of Type II, dominated the methane-oxidizing bacteria (MOB) community, whereas Methanocorpusculum was the predominant methanogen. Higher numbers of operational taxonomic units (OTUs) representing Type I than Type II MOB were found in all crusts. Potential CH4 oxidation...... rates were determined by incubating crusts with CH4, and CH4 oxidization was observed in cattle, but not in swine slurry crusts. Conclusions: Slurry surface crusts harbour a diverse microbial community. Type I MOB are more diverse and abundant than Type II MOB in this environment. The distinct CH4...

  15. Device for continuous radiometric determination of the calcium and iron content in raw slurry for cement

    International Nuclear Information System (INIS)

    Wasilewska, M.; Ostachowicz, J.; Lankosz, M.; Molodynska, W.

    1975-01-01

    The characteristic iron and calcium-K series were excited using a Cd-109 isotope source. In order to determine the calcium and iron content in dry slurry, the Compton-effect scattered radiation of the Cd-109 source in the sample was used. A numerical process was worked out which allowed the elimination of the influence of changing contents of iron and water on the results of the calcium content determinations, and a device for continuous radiometric determination of calcium and iron in raw slurry was designed and constructed. The device was installed in the cement plant 'Przyjazn' under technical measuring conditions and its applicability was tested. (orig./LH) [de

  16. Upgrading of the Solid Fraction of Pig Slurry as Phosphorus Fertilizer

    DEFF Research Database (Denmark)

    Christel, Wibke

    Improved recycling of the solid fraction of separated pig slurry, which is considerably enriched in the essential plant nutrient phosphorus (P), could balance the P input in differently used agricultural areas and reduce the unsustainable depletion of the limited P rock reserves. By subsequent...... biological or thermal treatment, the P concentration of the pig slurry-derived products is furthermore increased, but these processes are also expected to affect P availability from the respective products. Consequently it was the overall objective of this PhD project to identify options for upgrading...

  17. Slurry circulation after cement compression operations; Circulacao de pasta apos operacoes de compressao de cimento

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Clavio Roberto S [PETROBRAS, BA (Brazil). Regiao de Producao da Bahia. Divisao Regional de Complementacao

    1994-07-01

    In the traditional low pressure cement compression method, after pressure stabilization we wait for the setting and remove the hardened cement with a rock bit. The method described here suggests that following pressure stabilization, the slurry must be removed from the casing with reverse circulation, thus excluding the whole process of cutting hardened cement, optimizing rig time and equipment wear, and anticipating oil production. This work describes this experience in Reconcavo basin, Potiguar basin, and Campos basin, production regions of PETROBRAS, and suggests slurry parameters and a methodology to employ the method. (author)

  18. Side-band injection of acidified cattle slurry as starter P-fertilization for maize seedlings

    DEFF Research Database (Denmark)

    Petersen, Jens; Lemming, Camilla; Rubæk, Gitte Holton

    Accumulation of phosphorus (P) in agricultural soils has caused increasing environmental concerns. Maize cropped for fodder implies return of animal manures rich in nutrients. In addition, starter fertilization with mineral P is used in cold conditions for maize cropping. It was hypothesized...... that the use of the additional mineral P could be excluded by increased availability of the P applied by animal manures. In a growth chamber experiment we investigated the effect of acidified slurry on the growth and nutrient uptake in maize seedlings. In special designed pot the slurries and mineral reference...

  19. Microencapsulated PCM slurry for heat transfer media. 4. Reduction of undercooling

    International Nuclear Information System (INIS)

    Akino, Norio; Nakano, Fumihiko; Kubo, Shinji; Nagashima, Akira; Sagiya, Syojiro; Nakanishi, Masayuki.

    1997-01-01

    New heat transfer media with large heat capacity is under development, using a slurry of microencapsulated-phase-change-material (MCPCM) mixed into carrying liquid. To prepare stable MCPCM slurry, fatty acid is selected as PCM owing to relatively large density, and diameter of MCPCM particles are below 10 μm. The temperature difference between melting and freezing points, the so-called undercooling becomes remarkable. To reduce the undercooling, an additive is mixed into fatty acid to introduce nucleation cites. It is concluded that Hexatriacontane is effective to remove undercooling of microencapsulated Lauric acid, Myristic acid and their mixture, and Sebacic acid is effective for Lauric acid. (author)

  20. Kinetics of Slurry Phase Fischer-Tropsch Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Dragomir B. Bukur; Gilbert F. Froment; Tomasz Olewski; Lech Nowicki; Madhav Nayapati

    2006-12-31

    The overall objective of this project is to develop a comprehensive kinetic model for slurry-phase Fischer-Tropsch synthesis (FTS) employing iron-based catalysts. This model will be validated with experimental data obtained in a stirred-tank slurry reactor (STSR) over a wide range of process conditions. Three STSR tests of the Ruhrchemie LP 33/81 catalyst were conducted to collect data on catalyst activity and selectivity under 25 different sets of process conditions. The observed decrease in 1-olefin content and increase in 2-olefin and n-paraffin contents with the increase in conversion are consistent with a concept that 1-olefins participate in secondary reactions (e.g. 1-olefin hydrogenation, isomerization and readsorption), whereas 2-olefins and n-paraffins are formed in these reactions. Carbon number product distribution showed an increase in chain growth probability with increase in chain length. Vapor-liquid equilibrium calculations were made to check validity of the assumption that the gas and liquid phases are in equilibrium during FTS in the STSR. Calculated vapor phase compositions were in excellent agreement with experimental values from the STSR under reaction conditions. Discrepancies between the calculated and experimental values for the liquid-phase composition (for some of the experimental data) are ascribed to experimental errors in the amount of wax collected from the reactor, and the relative amounts of hydrocarbon wax and Durasyn 164 oil (start-up fluid) in the liquid samples. Kinetic parameters of four kinetic models (Lox and Froment, 1993b; Yang et al., 2003; Van der Laan and Beenackers, 1998, 1999; and an extended kinetic model of Van der Laan and Beenackers) were estimated from experimental data in the STSR tests. Two of these kinetic models (Lox and Froment, 1993b; Yang et al., 2003) can predict a complete product distribution (inorganic species and hydrocarbons), whereas the kinetic model of Van der Laan and Beenackers (1998, 1999) can

  1. Kinetics of Slurry Phase Fischer-Tropsch Synthesis

    International Nuclear Information System (INIS)

    Dragomir B. Bukur; Gilbert F. Froment; Tomasz Olewski; Lech Nowicki; Madhav Nayapati

    2006-01-01

    The overall objective of this project is to develop a comprehensive kinetic model for slurry-phase Fischer-Tropsch synthesis (FTS) employing iron-based catalysts. This model will be validated with experimental data obtained in a stirred-tank slurry reactor (STSR) over a wide range of process conditions. Three STSR tests of the Ruhrchemie LP 33/81 catalyst were conducted to collect data on catalyst activity and selectivity under 25 different sets of process conditions. The observed decrease in 1-olefin content and increase in 2-olefin and n-paraffin contents with the increase in conversion are consistent with a concept that 1-olefins participate in secondary reactions (e.g. 1-olefin hydrogenation, isomerization and readsorption), whereas 2-olefins and n-paraffins are formed in these reactions. Carbon number product distribution showed an increase in chain growth probability with increase in chain length. Vapor-liquid equilibrium calculations were made to check validity of the assumption that the gas and liquid phases are in equilibrium during FTS in the STSR. Calculated vapor phase compositions were in excellent agreement with experimental values from the STSR under reaction conditions. Discrepancies between the calculated and experimental values for the liquid-phase composition (for some of the experimental data) are ascribed to experimental errors in the amount of wax collected from the reactor, and the relative amounts of hydrocarbon wax and Durasyn 164 oil (start-up fluid) in the liquid samples. Kinetic parameters of four kinetic models (Lox and Froment, 1993b; Yang et al., 2003; Van der Laan and Beenackers, 1998, 1999; and an extended kinetic model of Van der Laan and Beenackers) were estimated from experimental data in the STSR tests. Two of these kinetic models (Lox and Froment, 1993b; Yang et al., 2003) can predict a complete product distribution (inorganic species and hydrocarbons), whereas the kinetic model of Van der Laan and Beenackers (1998, 1999) can

  2. Modeling Megacusps and Dune Erosion

    Science.gov (United States)

    Orzech, M.; Reniers, A. J.; Thornton, E. B.

    2009-12-01

    Megacusps are large, concave, erosional features of beaches, of O(200m) alongshore wavelength, which sometimes occur when rip channel bathymetry is present. It is commonly hypothesized that erosion of the dune and back beach will be greater at the alongshore locations of the megacusp embayments, principally because the beach width is narrower there and larger waves can more easily reach the dune toe (e.g., Short, J. Geol., 1979, Thornton, et al., Mar. Geol., 2007). At present, available field data in southern Monterey Bay provide some support for this hypothesis, but not enough to fully confirm or refute it. This analysis utilizes XBeach, a 2DH nearshore sediment transport model, to test the above hypothesis under a range of wave conditions over several idealized rip-megacusp bathymetries backed by dunes. Model results suggest that while specific wave conditions may result in erosional hot spots at megacusp embayments, other factors such as tides, wave direction, and surf zone bathymetry can often play an equal or stronger role.

  3. [Gastric band erosion: Alternative management].

    Science.gov (United States)

    Echaverry-Navarrete, Denis José; Maldonado-Vázquez, Angélica; Cortes-Romano, Pablo; Cabrera-Jardines, Ricardo; Mondragón-Pinzón, Erwin Eduardo; Castillo-González, Federico Armando

    2015-01-01

    Obesity is a public health problem, for which the prevalence has increased worldwide at an alarming rate, affecting 1.7 billion people in the world. To describe the technique employed in incomplete penetration of gastric band where endoscopic management and/or primary closure is not feasible. Laparoscopic removal of gastric band was performed in five patients with incomplete penetrance using Foley catheterization in the perforation site that could lead to the development of a gastro-cutaneous fistula. The cases presented include a leak that required surgical lavage with satisfactory outcome, and one patient developed stenosis 3 years after surgical management, which was resolved endoscopically. In all cases, the penetration site closed spontaneously. Gastric band erosion has been reported in 3.4% of cases. The reason for inserting a catheter is to create a controlled gastro-cutaneous fistula, allowing spontaneous closure. Various techniques have been described: the totally endoscopic, hybrid techniques (endoscopic/laparoscopic) and completely laparoscopic. A technique is described here that is useful and successful in cases where the above-described treatments are not viable. Copyright © 2015. Published by Masson Doyma México S.A.

  4. Zeolite Combined with Alum and Polyaluminum Chloride Mixed with Agricultural Slurries Reduces Carbon Losses in Runoff from Grassed Soil Boxes.

    Science.gov (United States)

    Murnane, J G; Brennan, R B; Fenton, O; Healy, M G

    2016-11-01

    Carbon (C) losses from agricultural soils to surface waters can migrate through water treatment plants and result in the formation of disinfection by-products, which are potentially harmful to human health. This study aimed to quantify total organic carbon (TOC) and total inorganic C losses in runoff after application of dairy slurry, pig slurry, or milk house wash water (MWW) to land and to mitigate these losses through coamendment of the slurries with zeolite (2.36-3.35 mm clinoptilolite) and liquid polyaluminum chloride (PAC) (10% AlO) for dairy and pig slurries or liquid aluminum sulfate (alum) (8% AlO) for MWW. Four treatments under repeated 30-min simulated rainfall events (9.6 mm h) were examined in a laboratory study using grassed soil runoff boxes (0.225 m wide, 1 m long; 10% slope): control soil, unamended slurries, PAC-amended dairy and pig slurries (13.3 and 11.7 kg t, respectively), alum-amended MWW (3.2 kg t), combined zeolite and PAC-amended dairy (160 and 13.3 kg t zeolite and PAC, respectively) and pig slurries (158 and 11.7 kg t zeolite and PAC, respectively), and combined zeolite and alum-amended MWW (72 and 3.2 kg t zeolite and alum, respectively). The unamended and amended slurries were applied at net rates of 31, 34, and 50 t ha for pig and dairy slurries and MWW, respectively. Significant reductions of TOC in runoff compared with unamended slurries were measured for PAC-amended dairy and pig slurries (52 and 56%, respectively) but not for alum-amended MWW. Dual zeolite and alum-amended MWW significantly reduced TOC in runoff compared with alum amendment only. We conclude that use of PAC-amended dairy and pig slurries and dual zeolite and alum-amended MWW, although effective, may not be economically viable to reduce TOC losses from organic slurries given the relatively low amounts of TOC measured in runoff from unamended slurries compared with the amounts applied. Copyright © by the American Society of Agronomy, Crop Science Society of

  5. Preparatory studies for the on-line determination of zinc content in zinc ore slurries by radioisotope excited X-ray fluorescence

    International Nuclear Information System (INIS)

    Donhoffer, D.K.

    1977-01-01

    Laboratory tests were carried out to prove the feasibility of determination of Zn-content in zinc ore slurries by isotope excited x-ray fluorescence. Matrix effects were investigated on dry samples. A slurry testloop was built and measurements on slurries were made. The results indicated that the measurement on Zn in ore slurries can be made with a precision of 0,05% Zn. A working equation for interpretation of the measurements is derived. (author)

  6. A methodology to define the flow rate and pressure requirements for transfer of double-shell tank waste slurries

    International Nuclear Information System (INIS)

    Bamberger, J.A.; Liljegren, L.M.

    1993-04-01

    This document presents an analysis of the pressure drop and flow rate double-shell tank slurries. Experiments to requirements for transport of characterize the transport of double-shell tank slurries through piping networks and to resuspend materials that settle during pump outages are proposed. Reported values of physical properties of double-shell tank slurries were analyzed to evaluate the flow regimes that are likely to occur during transport. The results of these evaluations indicate that the slurry will be pseudohomogeneous during transport and that the slurry rheology is sufficiently non-Newtonian to affect both the pressure drop achieved during transport and the critical Reynolds number. The transport data collected in the non-Newtonian experiment will be used to determine whether a non-Newtonian correlation developed by Hanks (1978) adequately describes the experimental results

  7. Compressor Impeller Erosion Resistant Surface Treatment

    National Research Council Canada - National Science Library

    Riley, Michael

    2000-01-01

    ...). Coatings based on tungsten carbide tantalum carbide. titanium carbide all with a cobalt matrix were evaluated for high velocity particle erosion in conventional wear test studies as well as wind tunnel testing...

  8. Puerto Rico Relative Vulnerability to Erosion

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical factors, such as the slope of the land, the texture of the soil, and the precipitation regime influence erosion in an area. Parts of Puerto Rico are very...

  9. Paradiaphyseal calcific tendinitis with cortical bone erosion.

    Science.gov (United States)

    Fritz, P; Bardin, T; Laredo, J D; Ziza, J M; D'Anglejan, G; Lansaman, J; Bucki, B; Forest, M; Kuntz, D

    1994-05-01

    To determine the clinical, radiologic, and histologic features of calcific tendinitis with cortical bone erosion. The records of 6 patients with paradiaphyseal calcific tendinitis and adjacent bone cortex erosion were reviewed. Calcific tendinitis involved the linea aspera in 4 patients, the bicipital groove in 1 patient, and the deltoid insertion in another. Calcium deposits were associated with cortical bone erosions, revealed on plain radiographs in 4 patients and computed tomography scans in 2. Bone scans were performed in 2 patients and showed local hyperfixation of the isotope. In 4 patients, suspicion of a neoplasm led to a biopsy. Calcium deposits appeared to be surrounded by a foreign body reaction with numerous giant cells. Apatite crystals were identified by transmission electron microscopy and elemental analysis in 1 surgical sample. Paradiaphyseal calcific tendinitis with cortical bone erosion is an uncommon presentation of apatite deposition disease.

  10. Emission Facilities - Erosion & Sediment Control Facilities

    Data.gov (United States)

    NSGIC Education | GIS Inventory — An Erosion and Sediment Control Facility is a DEP primary facility type related to the Water Pollution Control program. The following sub-facility types related to...

  11. Understanding and Predicting Gun Barrel Erosion

    National Research Council Canada - National Science Library

    Johnston, Ian A

    2005-01-01

    The Australian Defence Force will soon have to contend with gun barrel erosion issues arising from the use of new low-vulnerability gun propellants, the acquisition of new ammunition and gun systems...

  12. Puerto Rico Relative Erosion Potential (REP) - 2000

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The relative erosion potential is an indicator of sediment and pollution runoff from land based on slope, soil type, land cover (circa 2000) and (maximum monthly)...

  13. Puerto Rico Relative Erosion Potential (REP) - 1990

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The relative erosion potential is an indicator of sediment and pollution runoff from land based on slope, soil type, land cover (circa 1990) and (maximum monthly)...

  14. Definition of tolerable soil erosion values

    Directory of Open Access Journals (Sweden)

    G. Sparovek

    1997-09-01

    Full Text Available Although the criteria for defining erosion tolerance are well established, the limits generally used are not consistent with natural, economical and technological conditions. Rates greater than soil formation can be accepted only until a minimum of soil depth is reached, provided that they are not associated with environmental hazard or productivity losses. A sequence of equations is presented to calculate erosion tolerance rates through time. The selection of equation parameters permits the definition of erosion tolerance rates in agreement with environmental, social and technical needs. The soil depth change that is related to irreversible soil degradation can be calculated. The definition of soil erosion tolerance according to these equations can be used as a guideline for sustainable land use planning and is compatible with expert systems.

  15. PROBLEMS OF SOIL PROTECTION FROM EROSION

    Directory of Open Access Journals (Sweden)

    M. Voloshuk

    2007-10-01

    Full Text Available In this article the problems of soil protection from erosion in Moldova are considered. The history (evolution of erosive processes is generalized, the first items of information on presence washed off soils are marked. Purposeful study of soil erosion, development of measures of struggle with it were begun in Moldova at the end of 40 years. In connection with transition to new economic methods of conducting economy (farmers, rent, privatization of land before pedologist, the experts of design organizations put forward the new requirements to study of erosive processes, development of soil protection, ecologo-adaptive systems of landscape agriculture. The tasks for improvement of a soil cover, restoration of fertility soil and their protection are put forward which are necessary for deciding in a near future.

  16. Rain Erosion/Measurement Impact Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The FARM Rain Erosion/Impact Measurement Lab develops solutions for deficiencies in the ability of materials, coatings and designs to withstand a severe operational...

  17. Soil erosion assessment - Mind the gap

    Science.gov (United States)

    Kim, Jongho; Ivanov, Valeriy Y.; Fatichi, Simone

    2016-12-01

    Accurate assessment of erosion rates remains an elusive problem because soil loss is strongly nonunique with respect to the main drivers. In addressing the mechanistic causes of erosion responses, we discriminate between macroscale effects of external factors - long studied and referred to as "geomorphic external variability", and microscale effects, introduced as "geomorphic internal variability." The latter source of erosion variations represents the knowledge gap, an overlooked but vital element of geomorphic response, significantly impacting the low predictability skill of deterministic models at field-catchment scales. This is corroborated with experiments using a comprehensive physical model that dynamically updates the soil mass and particle composition. As complete knowledge of microscale conditions for arbitrary location and time is infeasible, we propose that new predictive frameworks of soil erosion should embed stochastic components in deterministic assessments of external and internal types of geomorphic variability.

  18. MALIGNANT TRANSFORMATION OF EROSIVE ORAL LICHEN PLANUS

    Directory of Open Access Journals (Sweden)

    Siti Chumaeroh

    2006-04-01

    Full Text Available Lichen planus is a relatively common inflammatory disorder which may have cutaneous and or mucosal manifestation. The malignant potential of oral lichen planus is still debatable. Some authors are sceptical about the premalignant nature of the disease, while other investigators have reported that malignant transformations occur in 1-10% of the cases. The aim of this study is to report a case of erosive lichen plans which shows malignant transformation of histopathologic examination. A man of 39 years old visited the Dental Department or Kajradi's Hospital with pain symptoms of the palate, buccal and gingival mucosa on both sides for 6 months. The physical examination shows the white lesion with striae configuration and pain, red erosive area inside the palate extends to the buccal mucosa and the gingival mucosa. The suspect diagnosis is erosive lichen planus, but the histopathologic examination shows epidermoid carcinoma. It is concluded that erosive oral lichen planus has the potential to transform into epidermoid carcinoma.

  19. Dental erosion: understanding this pervasive condition.

    Science.gov (United States)

    Almeida e Silva, Júnio S; Baratieri, Luiz Narciso; Araujo, Edson; Widmer, Nicolas

    2011-08-01

    Dental erosion is a contemporary disease, mostly because of the change of the eating patterns that currently exist in society. It is a "silent" and multifactorial disease, and is highly influenced by habits and lifestyles. The prevalence of dental erosion has considerably increased, with this condition currently standing as a great challenge for the clinician, regarding the diagnosis, identification of the etiological factors, prevention, and execution of an adequate treatment. This article presents a dental erosion review and a case report of a restorative treatment of dental erosion lesions using a combination of bonded ceramic overlays to reestablish vertical dimension and composite resin to restore the worn palatal and incisal surfaces of the anterior upper teeth. Adequate function and esthetics can be achieved with this approach. © 2011 Wiley Periodicals, Inc.

  20. Numerical and experimental investigations on cavitation erosion

    Science.gov (United States)

    Fortes Patella, R.; Archer, A.; Flageul, C.

    2012-11-01

    A method is proposed to predict cavitation damage from cavitating flow simulations. For this purpose, a numerical process coupling cavitating flow simulations and erosion models was developed and applied to a two-dimensional (2D) hydrofoil tested at TUD (Darmstadt University of Technology, Germany) [1] and to a NACA 65012 tested at LMH-EPFL (Lausanne Polytechnic School) [2]. Cavitation erosion tests (pitting tests) were carried out and a 3D laser profilometry was used to analyze surfaces damaged by cavitation [3]. The method allows evaluating the pit characteristics, and mainly the volume damage rates. The paper describes the developed erosion model, the technique of cavitation damage measurement and presents some comparisons between experimental results and numerical damage predictions. The extent of cavitation erosion was correctly estimated in both hydrofoil geometries. The simulated qualitative influence of flow velocity, sigma value and gas content on cavitation damage agreed well with experimental observations.