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Sample records for in-situ combustion processes

  1. Compositional Simulation of In-Situ Combustion EOR: A Study of Process Characteristics

    DEFF Research Database (Denmark)

    Jain, Priyanka; Stenby, Erling Halfdan; von Solms, Nicolas

    2010-01-01

    and multidisciplinary process data. This paper extends the understanding of previous research done in this domain by performing the process simulations to study further the impact of oxidation reactions and combustion reactions of crude oils along with their saturate, aromatic, resin, and asphaltene (SARA) fractions......In order to facilitate the study of the influence of reservoir process characteristics in In-Situ combustion modeling and advance the work of Kristensen et al. in this domain; a fully compositional In-situ combustion (ISC) model of Virtual Kinetic Cell (VKC; single-cell model) for laboratory scale...... combustion simulation is used. Preceding research work primarily focused on a kinetic model that was based on six components and incorporated four chemical reactions. However, modeling of a thermal process as complex as In-situ combustion requires in-depth understanding of detailed reaction kinetics...

  2. Experimental Investigation and High Resolution Simulation of In-Situ Combustion Processes

    Energy Technology Data Exchange (ETDEWEB)

    Margot Gerritsen; Tony Kovscek

    2008-04-30

    This final technical report describes work performed for the project 'Experimental Investigation and High Resolution Numerical Simulator of In-Situ Combustion Processes', DE-FC26-03NT15405. In summary, this work improved our understanding of in-situ combustion (ISC) process physics and oil recovery. This understanding was translated into improved conceptual models and a suite of software algorithms that extended predictive capabilities. We pursued experimental, theoretical, and numerical tasks during the performance period. The specific project objectives were (i) identification, experimentally, of chemical additives/injectants that improve combustion performance and delineation of the physics of improved performance, (ii) establishment of a benchmark one-dimensional, experimental data set for verification of in-situ combustion dynamics computed by simulators, (iii) develop improved numerical methods that can be used to describe in-situ combustion more accurately, and (iv) to lay the underpinnings of a highly efficient, 3D, in-situ combustion simulator using adaptive mesh refinement techniques and parallelization. We believe that project goals were met and exceeded as discussed.

  3. Study of the Radical Chain Mechanism of Hydrocarbon Oxidation for In Situ Combustion Process

    Directory of Open Access Journals (Sweden)

    Alexandra Ushakova

    2017-01-01

    Full Text Available Despite the abundance of in situ combustion models of oil oxidation, many of the effects are still beyond consideration. For example, until now, initial stages of oxidation were not considered from a position of radical chain process. This is a serious difficulty for the simulation of oil recovery process that involves air injection. To investigate the initial stages of oxidation, the paper considers the sequence of chemical reactions, including intermediate short-living compounds and radicals. We have attempted to correlate the main stages of the reaction with areas of heat release observed in the experiments. The system of differential equations based on the equations of oxidation reactions was solved. Time dependence of peroxides formation and start of heat release is analytically derived for the initial stages. We have considered the inhibition of initial oxidation stages by aromatic oil compounds and have studied the induction time in dependence on temperature. Chain ignition criteria for paraffins and crude oil in presence of core samples were obtained. The calculation results are compared with the stages of oxidation that arise by high-pressure differential scanning calorimetry. According to experimental observations we have determined which reactions are important for the process and which can be omitted or combined into one as insignificant.

  4. In situ combustion field experiences in Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Villalba, M.; Estrada, M.; Bolivar, J. [INTEVEP, Caracas (Venezuela)

    1995-02-01

    A literature review of four in situ combustion projects: in Miga, Tia Juana, Melones and Morichal fields in Venezuela was made, and a summary of these projects is presented. Reservoir description and project performance data were analyzed. The behavior of the four in situ combustion field tests can be summarized as follows: The problems most often encountered were corrosion and high temperature producing wells. The direction in which the burning front moved was guided essentially by reservoir characteristics. The produced oil was upgraded by about 4{degrees} API, and viscosity was substantially reduced. For Mirochal and Miga fields, the analyses of available information from the combustion projects indicated that the process has been successful in the affected region. Conclusions from this review indicate that the two most frequent problems encountered were operational problems in producing wells and the direction of the burning front. The heterogeneous nature of the sands probably resulted in the burning front moving in a preferential direction, hence reducing areal sweep efficiency.

  5. Environmental survey - tar sands in situ processing research program (Vernal, Uintah County, Utah). [Reverse-forward combustion; steam injection

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, Q.

    1980-03-01

    Research will be done on the reverse-forward combustion and steam injection for the in-situ recovery of oil from tar sands. This environmental survey will serve as a guideline for the consideration of environmental consequences of such research. It covers the construction phase, operational phase, description of the environment, potential impacts and mitigations, coordination, and alternatives. (DLC)

  6. Absolute laser based in-situ determination of HCl in the reaction chamber of combustion processes and gasification processes; Absolute laserbasierte in situ Bestimmung von HCI im Reaktionsraum von Verbrennungs- und Vergasungsprozessen

    Energy Technology Data Exchange (ETDEWEB)

    Ortwein, P.; Woiwode, W.; Gisi, M.; Ebert, V.; Wagner, S. [Heidelberg Univ. (Germany). Physikalisch Chemisches Institut; Eberhard, M.; Kolb, T. [ITC-TAB, Forschungszentrum Karlsruhe, Eggenstein-Leopoldshafen (Germany)

    2009-07-01

    The release of hydrochloric acid (HCl) is an important parameter for the industrial processes of combustion and gasification. This parameter has to be determined for the active monitoring till to the ppm range. On basis of a Vertical Cavity Surface Emitting laser (VCSEL) with 1,742 nm a new TDLAS spectrometer for the absolute in situ determination of hydrochloric acid during the processes of combustion and gasification was developed and used for a calibration-free absorption measurement of the HCl R3 line with minimal transversal sensitivity to the disturbing species CO{sub 2} and H{sub 2}O. In an extractive application with a 10 cm long gas cell, an optical dissolution of 10{sup -}4 and a detection limit of 240 ppb . m at a time resolution of 12.5 s can be achieved. In the case of a time resolution of 1 s, the application of the spectrometer in the case of in-situ measurements in a biomass combustion (T = 900 C, p = 1 bar, L = 36 cm) resulted in an optical dissolution of 1.9 . 10{sup -}4. This corresponds to a detection limit of 9 ppm . m and a signal-noise ratio of 25: 1. First in-situ measurements in an air flow gasifier (T = 1,100 C, p = 1 bar, L = 28 cm) supply an optical dissolution of 2.3 . 10{sup -}4 and a detection limit of 13 ppm . m.

  7. Numerical analysis of a one-dimensional multicomponent model of the in-situ combustion process

    DEFF Research Database (Denmark)

    Nesterov, Igor; Shapiro, Alexander; Stenby, Erling Halfdan

    2013-01-01

    , the model is based on SARA representation of a petroleum mixture (saturates–aromatics–resins–asphaltenes), which may react differently with oxygen and produce other components (for example, light oils and coke). In total, the model contains 14 components, which may undergo 15 chemical reactions. The set...... of reactions in the original model of M.R. Kristensen has been modified in order to account for secondary combustion of the light oil fraction. The results of the model implementation are applied to the four heavy oil systems and qualitatively compared to the results of previous experimental studies. A new...

  8. In-situ combustion with solvent injection

    Energy Technology Data Exchange (ETDEWEB)

    D' Silva, J.; Kakade, G. [Society of Petroleum Engineers, Kuala Lumpur (Malaysia)]|[Maharashtra Inst. of Technology, Pune (India)

    2008-10-15

    The effects of combining in situ combustion and heavy hydrocarbon naphtha vapor injection techniques in a heavy oil reservoir were investigated. Oil production rates and steam injection efficiencies were considered. The technique was also combined with toe-to-heel air injection (THAI) processes. The study showed that the modified THAI process achieved high rates of recovery for both primary production and as a follow-up technique in partially depleted reservoirs after cyclic steam and cold production. Oil produced using the modified THAI technique was also partially upgraded by the process. Results of the vapour chamber pressure calculations showed that the volume of oil produced by naphtha assisted gravity drainage was between 1 to 3 times higher than amounts of oil produced by SAGD processes during the same amount of time. The naphtha injection process produced more oil than the steam only process. However, high amounts of naphtha were needed to produce oil. Injection and production rates during the naphtha injection process were higher. Naphtha vapor was injected near the heel of a horizontal producer well. The vapor acted as a thermal and diluent mechanism in order to reduce the viscosity of the heavy oil . 9 refs., 4 tabs., 6 figs.

  9. Modeling of in-situ combustion as thermal recovery method for heavy (medium) oil (poster)

    NARCIS (Netherlands)

    Khoshnevis Gargar, N.; Achterbergh, N.; Rudolph, E.S.J.; Bruining, J.

    2010-01-01

    In-situ combustion (ISC), as a well known process for secondary and tertiary oil recovery, is an important alternative approach to achieve higher production efficiency for light and heavy oil reservoirs. The in-situ combustion process is a complex combination of a number of processes which occur in

  10. GAS TURBINE REHEAT USING IN SITU COMBUSTION

    Energy Technology Data Exchange (ETDEWEB)

    D.M. Bachovchin; T.E. Lippert; R.A. Newby P.G.A. Cizmas

    2004-05-17

    In situ reheat is an alternative to traditional gas turbine reheat design in which fuel is fed through airfoils rather than in a bulky discrete combustor separating HP and LP turbines. The goals are to achieve increased power output and/or efficiency without higher emissions. In this program the scientific basis for achieving burnout with low emissions has been explored. In Task 1, Blade Path Aerodynamics, design options were evaluated using CFD in terms of burnout, increase of power output, and possible hot streaking. It was concluded that Vane 1 injection in a conventional 4-stage turbine was preferred. Vane 2 injection after vane 1 injection was possible, but of marginal benefit. In Task 2, Combustion and Emissions, detailed chemical kinetics modeling, validated by Task 3, Sub-Scale Testing, experiments, resulted in the same conclusions, with the added conclusion that some increase in emissions was expected. In Task 4, Conceptual Design and Development Plan, Siemens Westinghouse power cycle analysis software was used to evaluate alternative in situ reheat design options. Only single stage reheat, via vane 1, was found to have merit, consistent with prior Tasks. Unifying the results of all the tasks, a conceptual design for single stage reheat utilizing 24 holes, 1.8 mm diameter, at the trailing edge of vane 1 is presented. A development plan is presented.

  11. In-situ combustion simulation with dynamic grid; Simulacao de combustao in-situ com grades dinamicas

    Energy Technology Data Exchange (ETDEWEB)

    Ferraz, C.H.A.; Almeida, M.P.; Vasconcelos, H.H.M.; Oliveira, C.L.N. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Fisica

    2008-07-01

    In this work, we study the effects of the introduction of 3D dynamics grids on in-situ combustion simulation results as means of describing the most realistically possible the dynamics of these processes, in particular of the combustion front. The dynamic refinement of grid blocks is important because in thesis it enhances the precision in the calculations once that more grid blocks are considered in the grid, especially within the narrow region of high temperature of the combustion front. We have performed dry combustion simulation (only water injection) and wet combustion simulation (air + water injection) for forward combustion in a variety of well configurations. Our initial results have shown changes in oil, water and gas productions when we use dynamics grids in the simulations, making clear the relevance of its usage in the understanding of the dynamics of these processes. (author)

  12. In situ analysis of ash deposits from black liquor combustion

    Energy Technology Data Exchange (ETDEWEB)

    Bernath, P. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility]|[Univ. of Toronto, Ontario (Canada); Sinquefield, S.A. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility]|[Oregon State Univ., Eugene, OR (United States); Baxter, L.L.; Sclippa, G.; Rohlfing, C. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility; Barfield, M. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility]|[Univ. of Arizona, Tucson, AZ (United States)

    1996-05-01

    Aerosols formed during combustion of black liquor cause a significant fire-side fouling problem in pulp mill recovery boilers. The ash deposits reduce heat transfer effectiveness, plug gas passages, and contribute to corrosion. Both vapors and condensation aerosols lead to the formation of such deposits. The high ash content of the fuel and the low dew point of the condensate salts lead to a high aerosol and vapor concentration in most boilers. In situ measurements of the chemical composition of these deposits is an important step in gaining a fundamental understanding of the deposition process. Infrared emission spectroscopy is used to characterize the composition of thin film deposits resulting from the combustion of black liquor and the deposition of submicron aerosols and vapors. New reference spectra of Na{sub 2}SO{sub 4}, K{sub 2}SO{sub 4}, Na{sub 2}CO{sub 3} and K{sub 2}CO{sub 3} pure component films were recorded and compared with the spectra of the black liquor deposit. All of the black liquor emission bands were identified using a combination of literature data and ab initio calculations. Ab initio calculations also predict the locations and intensities of bands for the alkali vapors of interest. 39 refs., 9 figs.

  13. Les méthodes thermiques de production des hydrocarbures. Chapitre 5 : Combustion "in situ". Pricipes et études de laboratoire Thermal Methods of Hydrocarbon Production. Chapter 5 : "In Situ" Combustion. Principles and Laboratory Research

    Directory of Open Access Journals (Sweden)

    Burger J.

    2006-11-01

    Full Text Available II existe plusieurs variantes de la combustion in situ, suivant le sens de déplacement du front de combustion, à co-courant ou à contre-courant, et suivant la nature des fluides injectés, air seul ou injection combinée d'air et d'eau. Les réactions de pyrolyse, d'oxydation et de combustion mises en jeu par ces techniques sont discutées, en particulier la cinétique des principaux mécanismes réactionnels, l'importance du dépôt de coke et l'exothermicité des réactions d'oxydation et de combustion. Les résultats d'essais de déplacement unidirectionnel du front de combustion dans des cellules de laboratoire sont présentés et discutés. Enfin on indique les conditions pratiques d'application des méthodes de combustion in situ sur champ. Possible variations of in situ combustion technique ore as follows : forward or reverse combustion depending on the relative directions of the air flow and the combustion front, dry combustion if air is the only fluid injected into the oil-bearing formation, or fixe/woter flooding if water is injected along with air. The chemical reactions of pyrolysis, oxidation and combustion involved in these processes are described. The kinetics of these reactions is discussed as well as fuel availability in forward combustion and the exothermicity of the oxidation and combustion reactions. The results obtained in the laboratory when a combustion front propagates in unidirectional adiabatic tells are described and discussed. This type of experimentation provides extensive information on the characteristics of the processes. Screening criteria for the practical application of in situ combustion techniques are presented.

  14. Feasibility study of the in-situ combustion in shallow, thin, and multi-layered heavy oil reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, L. [Society of Petroleum Engineers, Kuala Lumpur (Malaysia)]|[Daqing Petroleum Inst., Beijing (China); Yu, D. [Daqing Petroleum Inst., Beijing (China); Gong, Y. [China National Petroleum Corp., Beijing (China). Liaohe Oilfield; Wang, P.; Zhang, L. [China National Petroleum Corp., Beijing (China). Huabei Oilfield; Liu, C. [China National Petroleum Corp., Beijing (China). JiLin Oilfield

    2008-10-15

    In situ combustion is a process where oxygen is injected into oil reservoirs in order to oxidize the heavier components of crude oil. The oil is driven towards the production wells by the combustion gases and steam generated by the combustion processes. This paper investigated dry and wet forward in situ combustion processes designed for an oil reservoir with thin sand layers. Laboratory and numerical simulations were conducted to demonstrate the feasibility of the processes in a shallow, thin, heterogenous heavy oil reservoir in China. Combustion tube experiments were conducted in order to determine fuel consumption rates. A numerical geological model was constructed to represent the reservoir conditions. Gas, water, oil and solid phases were modelled. Four processes were considered: cracking; pyrolysis of heavy fractions; the combustion of light and heavy fractions; and the combustion of coke. Oil recovery rates were calculated for a period of 10 years. Reactor experiments were conducted to investigate igniting temperatures and air injection rates using an apparatus comprised of an electric heater, oil sand pack tube and a computerized control system. Experiments were performed at different temperature and injection rates. The experiments demonstrated that ignition times and air volumes decreased when air temperature was increased. Results of the study showed that a 20 per cent increase in oil recovery using the in situ combustion processes. It was concluded that adequate air injection rates are needed to ensure effective combustion front movement. 4 refs., 6 tabs., 4 figs.

  15. An Equation-of-State Compositional In-Situ Combustion Model: A Study of Phase Behavior Sensitivity

    DEFF Research Database (Denmark)

    Kristensen, Morten Rode; Gerritsen, M. G.; Thomsen, Per Grove

    2009-01-01

    of in situ combustion processes is the formation and sustained propagation of a high-temperature combustion front. Using the models developed, we study the impact of phase behavior on ignition/extinction dynamics as a function of the operating conditions. We show that when operating close to ignition/extinction...... branches, a change of phase behavior model will shift the system from a state of ignition to a state of extinction or vice versa. For both the rigorous equation of state based and a simplified, but commonly used, K-value-based phase behavior description we identify areas of operating conditions which lead...... phase behavior sensitivity for in situ combustion, a thermal oil recovery process. For the one-dimensional model we first study the sensitivity to numerical discretization errors and provide grid density guidelines for proper resolution of in situ combustion behavior. A critical condition for success...

  16. Application of Fourier-transform infrared (FT-ir) spectroscopy to in-situ studies of coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Ottesen, D K; Thorne, L R

    1982-04-01

    The feasibility of using Fourier-transform infrared (FT-ir) spectroscopy for in situ measurement of gas phase species concentrations and temperature during coal combustion is examined. This technique is evaluated in terms of its potential ability to monitor several important chemical and physical processes which occur in pulverized coal combustion. FT-ir absorption measurements of highly sooting, gaseous hydrocarbon/air flames are presented to demonstrate the fundamental usefulness of the technique for in situ detection of gas phase temperatures and species concentrations in high temperature combustion environments containing coal, char, mineral matter and soot particles. Preliminary results for coal/gaseous fuel/air flames are given.

  17. Effect of metallic additives on in situ combustion of Huntington Beach crude experiments

    Energy Technology Data Exchange (ETDEWEB)

    Baena, C.J.; Castanier, L.M.; Brigham, W.E.

    1990-08-01

    The economics and applicability of an in-situ combustion process for the recovery of crude oil are dictated to a large extent by the nature and the amount of fuel formed during the process. The aim of this work is to use combustion tube studies to determine on a quantitative basis, how the nature and the amount of fuel formed could be changed by the presence of metallic additives. These experiments follow from the qualitative observations on the effect of metallic additives on the in-situ combustion of Huntington Beach crude oil made by De los Rios (1987) at SUPRI. He performed kinetic studies on the oxidation of Huntington Beach crude in porous media and showed that the nature of the fuel formed changed when metallic additives were present. Combustion tube runs were performed using the metallic additives: ferrous chloride (FeCl{sub 2{center dot}}4H{sub 2}O), zinc chloride (ZnCl{sub 2}) and stannic chloride (SnCl{sub 4{center dot}}5H{sub 2}O). Unconsolidated cores were prepared by mixing predetermined amounts of an aqueous solution of the metal salt, Huntington Beach crude oil, Ottawa sand and clay in order to achieve the desired fluid saturations. The mixture was then tamped into the combustion tube. Dry air combustion tube runs were performed keeping the conditions of saturation, air flux and injection pressure approximately the same during each run. The nature of the fuel formed and its impact on the combustion parameters were determined and compared with a control run -- an experiment performed with no metallic additive. 30 refs., 33 figs., 6 tabs.

  18. Scramjet Combustion Processes

    Science.gov (United States)

    2010-09-01

    plan for these flights is as follows: Scramjet Combustion Processes RTO-EN-AVT-185 11 - 21 HyShot 5 – A Free-Flying Hypersonic Glider HyShot...5 will be a hypersonic glider designed to fly at Mach 8. It will separate from its rocket booster in space and perform controlled manoeuvres as it...RTO-EN-AVT-185 11 - 1 Scramjet Combustion Processes Michael Smart and Ray Stalker Centre for Hypersonics The University of Queensland

  19. Microprobe sampling--photo ionization-time-of-flight mass spectrometry for in situ chemical analysis of pyrolysis and combustion gases: examination of the thermo-chemical processes within a burning cigarette.

    Science.gov (United States)

    Hertz, Romy; Streibel, Thorsten; Liu, Chuan; McAdam, Kevin; Zimmermann, Ralf

    2012-02-10

    A microprobe sampling device (μ-probe) has been developed for in situ on-line photo ionization mass spectrometric analysis of volatile chemical species formed within objects consisting of organic matter during thermal processing. With this approach the chemical signature occurring during heating, pyrolysis, combustion, roasting and charring of organic material within burning objects such as burning fuel particles (e.g., biomass or coal pieces), lit cigarettes or thermally processed food products (e.g., roasting of coffee beans) can be investigated. Due to its dynamic changes between combustion and pyrolysis phases the cigarette smoking process is particularly interesting and has been chosen as first application. For this investigation the tip of the μ-probe is inserted directly into the tobacco rod and volatile organic compounds from inside the burning cigarette are extracted and real-time analyzed as the glowing front (or coal) approaches and passes the μ-probe sampling position. The combination of micro-sampling with photo ionization time-of-flight mass spectrometry (PI-TOFMS) allows on-line intrapuff-resolved analysis of species formation inside a burning cigarette. Monitoring volatile smoke compounds during cigarette puffing and smoldering cycles in this way provides unparalleled insights into formation mechanisms and their time-dependent change. Using this technique the changes from pyrolysis conditions to combustion conditions inside the coal of a cigarette could be observed directly. A comparative analysis of species formation within a burning Kentucky 2R4F reference cigarette with μ-probe analysis reveals different patterns and behaviors for nicotine, and a range of semi-volatile aromatic and aliphatic species.

  20. The development of an electrochemical technique for in situ calibrating of combustible gas detectors

    Science.gov (United States)

    Shumar, J. W.; Lantz, J. B.; Schubert, F. H.

    1976-01-01

    A program to determine the feasibility of performing in situ calibration of combustible gas detectors was successfully completed. Several possible techniques for performing the in situ calibration were proposed. The approach that showed the most promise involved the use of a miniature water vapor electrolysis cell for the generation of hydrogen within the flame arrestor of a combustible gas detector to be used for the purpose of calibrating the combustible gas detectors. A preliminary breadboard of the in situ calibration hardware was designed, fabricated and assembled. The breadboard equipment consisted of a commercially available combustible gas detector, modified to incorporate a water vapor electrolysis cell, and the instrumentation required for controlling the water vapor electrolysis and controlling and calibrating the combustible gas detector. The results showed that operation of the water vapor electrolysis at a given current density for a specific time period resulted in the attainment of a hydrogen concentration plateau within the flame arrestor of the combustible gas detector.

  1. Application of Ceramic Coat Synthesized by In-Situ Combustion Synthesis to BF Tuyere

    Institute of Scientific and Technical Information of China (English)

    YANG Da-zheng; GUAN Yong; ZHANG Yue; LI Jing; HU Jun-ge; LI Wen-zhu

    2007-01-01

    A novel technology of tuyere protection is introduced. The ceramic coat is synthesized by using in-situ combustion process as the internal, external, and nose protecting coat of BF tuyeres. It can effectively protect the tuyeres and reduce heat loss by cooling water. The technology is quick-acting, easy to use, energy-saving and can make tuyeres have long service life. The feasibility of the application of the tuyere ceramic coat is discussed and the energy-saving effect of the tuyere is compared with that of the tuyeres lined with refractory.

  2. Detecting Combustion and Flow Features In Situ Using Principal Component Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, David [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Grout, Ray W. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Fabian, Nathan D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bennett, Janine Camille [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2009-03-01

    This report presents progress on identifying and classifying features involving combustion in turbulent flow using principal component analysis (PCA) and k-means clustering using an in situ analysis framework. We describe a process for extracting temporally- and spatially-varying information from the simulation, classifying the information, and then applying the classification algorithm to either other portions of the simulation not used for training the classifier or further simulations. Because the regions classified as being of interest take up a small portion of the overall simulation domain, it will consume fewer resources to perform further analysis or save these regions at a higher fidelity than previously possible. The implementation of this process is partially complete and results obtained from PCA of test data is presented that indicates the process may have merit: the basis vectors that PCA provides are significantly different in regions where combustion is occurring and even when all 21 species of a lifted flame simulation are correlated the computational cost of PCA is minimal. What remains to be determined is whether k-means (or other) clustering techniques will be able to identify combined combustion and flow features with an accuracy that makes further characterization of these regions feasible and meaningful.

  3. Modelling of CWS combustion process

    Science.gov (United States)

    Rybenko, I. A.; Ermakova, L. A.

    2016-10-01

    The paper considers the combustion process of coal water slurry (CWS) drops. The physico-chemical process scheme consisting of several independent parallel-sequential stages is offered. This scheme of drops combustion process is proved by the particle size distribution test and research stereomicroscopic analysis of combustion products. The results of mathematical modelling and optimization of stationary regimes of CWS combustion are provided. During modeling the problem of defining possible equilibrium composition of products, which can be obtained as a result of CWS combustion processes at different temperatures, is solved.

  4. Novel Instrumentation for In Situ Combustion Measurements Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the Phase I is to develop, demonstrate and test a novel instrument based on laser absorption diagnostics for fast, in situ measurements of important...

  5. Novel Instrumentation for In Situ Combustion Measurements Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the Phase I is to develop, demonstrate and test a novel instrument based on laser absorption diagnostics for fast, in situ measurements of...

  6. Simulation of Gas Injection-Heating Process of In Situ Combustion%火烧油层注气加热过程的模拟计算研究

    Institute of Scientific and Technical Information of China (English)

    潘竟军; 周杨平; 陈龙; 马远乐

    2012-01-01

    在火烧油层的注气加热过程中,需要根据点火需求优化注气参数.考虑了空气在井筒、油层的流动及换热过程,包括空气进入油层的混合过程、水蒸发进入空气和湿空气降温后凝结为水的组分及相态变化、油层之间的导热过程,建立了相应的瞬态模型,提出了基于龙格库塔法的求解方法.利用该模型及求解方法进行了模拟注气验证,并用于油田的实际火烧油层点火过程的监测系统.研究表明:点火过程中加热带扩展速度非常有限(6 d后加热带半径仍小于0.6m),并且受油层中含水率影响较大,加热带温度主要受电加热器功率和注气速度影响,受注气时间长短影响较小.点火过程中应保持电加热器功率和注气速度稳定.%It is necessary to optimize the parameters of gas injection heating during the gas injection-heating process in situ combustion. A transient model is proposed to simulate the flow and the heat exchange of air in the well tube and oil reservoirs including the mixing process of air and oil reservoirs, change of component and phase state such as evaporation of hot water and condensation of cold wet air, the heat exchange among different oil reservoirs and rock. A solving method based on Rung-Kutta and a simulation program is programmed. After the verification of simulating injection. This mathematical model and its solving method are applied to the simulation and monitoring of gas injection heating process in situ combustion at actual oil field. It was found that the extension of heating zone is slow (radius of heating zone is less than 0.6 m after a 5-day injection) and greatly influenced by the moisture content of oil reservoir, and the temperature of it is almost constant and determined by the power of electric heater and gas flow rate. The power of electric heater and gas flow rate should keep in a stable state during the heating process.

  7. Study for improving the in-situ combustion of Venezuela extra-heavy crude oil using unconventional additive

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza Rodriguez, A.J.; Perozo Hernandez, H. A.; Oliveros, D. A. [PDVSA Intevep (Venezuela); Reyes, N. [Universidad Central de Venezuela (Venezuela); Reinoza, J. [Universidad de los Andes (Colombia)

    2011-07-01

    With the depletion of conventional oil resources, heavy oil now accounts for an important part of both world and Venezuelan resources. Its recovery presents many challenges and a new in situ combustion process using additives was developed to address them. The aim of this study is to evaluate the benefits of the use of an additive to enhance the combustion process. Tests were performed with an inexpensive waste steam as additive and crude oil from the Orinoco oil belt. Six runs were performed, 2 were references and 4 used the additive placed in 2/3 of the total length of the cell. The use of additive led to more efficient combustion, greater stability of the combustion front, better oil recovery and the production of lighter compounds than without additive. This study demonstrated that the use of additive could be a promising opportunity for Venezuelan heavy oil operators.

  8. Capture of mercury in combustion systems by in situ-generated titania particles with UV irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Wu, C.Y.; Lee, T.G.; Tyree, G.; Arar, E.; Biswas, P. [University of Cincinnati, Cincinnati, OH (United States). Dept. of Civil and Environmental Engineering

    1998-10-01

    In situ-generated sorbent titania particles with ultraviolet (UV) irradiation have been shown to be effective in capture of mercury in combustor exhausts. Results of experiments conducted with the (1) sorbent precursor only, (2) mercury only, (3) mercury and UV irradiation, and (4) mercury, titania, and UV irradiation are presented to elucidate the mechanisms of the capture process. Capture efficiencies (percentage of Hg captured on the filter) as high as 96% were measured for mercury by titania with UV irradiation. A very high surface area titania sorbent was first formed, with mercury vapors condensing onto this surface, followed by photocatalytic oxidation and binding with the sorbent particles. The process has significant potential as a low-cost methodology for mercury control in practical combustion systems. Minimal retrofitting may be necessary as conventional particulate control devices such as electrostatic precipitators have coronas with UV radiation present.

  9. Research on In-situ Combustion Chemistry Mechanism%火烧油层化学机理研究

    Institute of Scientific and Technical Information of China (English)

    韩冠永; 刘永建; 耿志刚

    2015-01-01

    研究火烧油层化学机理,是为了改善火烧油层燃烧性能参数,而认识火烧油层技术最直接、最有效的研究手段之一是物理模拟实验,所以,借助火烧油层物理模拟实验来开展火烧油层化学机理及其改善方法研究是行之有效的。火烧油层复杂的化学机理使得火驱工艺过程的复杂性大大增加,对火烧油层化学反应的定性及定量分析是完善和发展火驱采油技术的基本途径。%In-situ combustion chemistry mechanism was studied in order to improve the combustion performance parameters of fire flooding. One of the most direct and effective research methods to understand the technology of fire flooding technology is the physical simulation experiment. The complex chemical mechanism of in-situ combustion makes the complexity of fire flooding process greatly increase. The basic way to improve and develop the technology of the fire flooding oil recovery is the qualitative and quantitative analysis of in-situ combustion chemical reaction.

  10. Kinetics of in situ combustion. SUPRI TR 91

    Energy Technology Data Exchange (ETDEWEB)

    Mamora, D.D.; Ramey, H.J. Jr.; Brigham, W.E.; Castanier, L.M.

    1993-07-01

    Oxidation kinetic experiments with various crude oil types show two reaction peaks at about 250{degree}C (482{degree}F) and 400{degree}C (725{degree}F). These experiments lead to the conclusion that the fuel during high temperature oxidation is an oxygenated hydrocarbon. A new oxidation reaction model has been developed which includes two partially-overlapping reactions: namely, low-temperature oxidation followed by high-temperature oxidation. For the fuel oxidation reaction, the new model includes the effects of sand grain size and the atomic hydrogen-carbon (H/C) and oxygen-carbon (O/C) ratios of the fuel. Results based on the new model are in good agreement with the experimental data. Methods have been developed to calculate the atomic H/C and O/C ratios. These methods consider the oxygen in the oxygenated fuel, and enable a direct comparison of the atomic H/C ratios obtained from kinetic and combustion tube experiments. The finding that the fuel in kinetic tube experiments is an oxygenated hydrocarbon indicates that oxidation reactions are different in kinetic and combustion tube experiments. A new experimental technique or method of analysis will be required to obtain kinetic parameters for oxidation reactions encountered in combustion tube experiments and field operations.

  11. Combustion Synthesis of NiAl and In-situ Joining to Ni-based Superalloy

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Combustion synthesis is used as a joining technology to join Ni-based superalloys with in-situ synthesized NiAl filler. The synthesis mechanism is discussed. The microstructure of the joints is investigated and the joint strength is also evaluated by tensile testing.

  12. 30 CFR 828.12 - In situ processing: Monitoring.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false In situ processing: Monitoring. 828.12 Section 828.12 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE... PROCESSING § 828.12 In situ processing: Monitoring. (a) Each person who conducts in situ...

  13. 30 CFR 828.11 - In situ processing: Performance standards.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false In situ processing: Performance standards. 828.11 Section 828.11 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT... STANDARDS-IN SITU PROCESSING § 828.11 In situ processing: Performance standards. (a) The person who...

  14. In Situ Field Testing of Processes

    Energy Technology Data Exchange (ETDEWEB)

    J. Wang

    2001-12-14

    The purpose of this Analysis/Model Report (AMR) is to update and document the data and subsequent analyses from ambient field-testing activities performed in underground drifts of the Yucca Mountain Site Characterization Project (YMP). This revision updates data and analyses presented in the initial issue of this AMR. This AMR was developed in accordance with the ''Technical Work Plan for Unsaturated Zone (UZ) Flow and Transport Process Model Report'' and ''Technical Work Plan for UZ Flow, Transport, and Coupled Processes Process Model Report. These activities were performed to investigate in situ flow and transport processes. The evaluations provide the necessary framework to: (1) refine and confirm the conceptual model of matrix and fracture processes in the unsaturated zone (UZ) and (2) analyze the impact of excavation (including use of construction water and effect of ventilation) on the UZ flow and transport processes. This AMR is intended to support revisions to ''Conceptual and Numerical Models for UZ Flow and Transport'' and ''Unsaturated Zone Flow and Transport Model Process Model Report''. In general, the results discussed in this AMR are from studies conducted using a combination or a subset of the following three approaches: (1) air-injection tests, (2) liquid-release tests, and (3) moisture monitoring using in-drift sensors or in-borehole sensors, to evaluate the impact of excavation, ventilation, and construction-water usage on the surrounding rocks. The liquid-release tests and air-injection tests provide an evaluation of in situ fracture flow and the competing processes of matrix imbibition. Only the findings from testing and data not covered in the ''Seepage Calibration Model and Seepage Testing Data'' are analyzed in detail in the AMR.

  15. In-Situ Characteristics of Particle Emissions from Biomass Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Pagels, Joakum; Wierzbicka, Aneta; Bohgard, Mats [Lund Univ. (Sweden). Div. of Ergonomics and Aerosol Technology; Strand, Michael; Lillieblad, Lena; Sanati, Mehri [Vaexjoe Univ. (Sweden). Bioenergy Technology; Swietlicki, Erik [Lund Univ. (Sweden). Div. of Nuclear Physics

    2005-07-01

    In this work we used a Scanning Mobility Particle Sizer and an Electrical Low-pressure Impactor to: a) Derive information of the particle morphology through air-borne analysis and b) Identify time and size variations of particle phase components from incomplete combustion and ash-components. The results presented here covers measurements in two moving grate boilers (12 MW operating on moist forest residue and 1.5 MW operating on wood pellets). We have previously shown that PM1 estimated from Electrical Low-Pressure Impactor (ELPI)-measurements consisted of a rather constant background with peaks correlating with CO and OGC peaks. In the 1.5 MW boiler EC contributed to 34% of PM1, while in the 12 MW boiler EC was below 0.5%. Figure 2 shows time variations in the 1.5 MW boiler as the current in three stages of the ELPI-impactor. Note that time-variations increase strongly with particle size. The fraction of the gravimetric mass detected as water-soluble ions (IC) decreased from {approx} 70% for dae= 78 and 133 nm to {approx} 25% for 322 and 510 nm particles and increased to around 50% for particles larger than 1 {mu}m. In the 12 MW boiler time variations were as low as for 128 nm particles and IC recovery was high for all studied particle sizes. Based on these data we conclude that PM consisting of ash-components are formed with small time variations mainly in mobility-sizes below 250 nm, while Elemental Carbon is emitted at high concentrations during peaks on the time-scale 10-30 s, mainly in particle sizes larger than 150 nm. However, the detailed mixing status of these two particle types/materials is still not known.

  16. Support Routines for In Situ Image Processing

    Science.gov (United States)

    Deen, Robert G.; Pariser, Oleg; Yeates, Matthew C.; Lee, Hyun H.; Lorre, Jean

    2013-01-01

    This software consists of a set of application programs that support ground-based image processing for in situ missions. These programs represent a collection of utility routines that perform miscellaneous functions in the context of the ground data system. Each one fulfills some specific need as determined via operational experience. The most unique aspect to these programs is that they are integrated into the large, in situ image processing system via the PIG (Planetary Image Geometry) library. They work directly with space in situ data, understanding the appropriate image meta-data fields and updating them properly. The programs themselves are completely multimission; all mission dependencies are handled by PIG. This suite of programs consists of: (1)marscahv: Generates a linearized, epi-polar aligned image given a stereo pair of images. These images are optimized for 1-D stereo correlations, (2) marscheckcm: Compares the camera model in an image label with one derived via kinematics modeling on the ground, (3) marschkovl: Checks the overlaps between a list of images in order to determine which might be stereo pairs. This is useful for non-traditional stereo images like long-baseline or those from an articulating arm camera, (4) marscoordtrans: Translates mosaic coordinates from one form into another, (5) marsdispcompare: Checks a Left Right stereo disparity image against a Right Left disparity image to ensure they are consistent with each other, (6) marsdispwarp: Takes one image of a stereo pair and warps it through a disparity map to create a synthetic opposite- eye image. For example, a right eye image could be transformed to look like it was taken from the left eye via this program, (7) marsfidfinder: Finds fiducial markers in an image by projecting their approximate location and then using correlation to locate the markers to subpixel accuracy. These fiducial markets are small targets attached to the spacecraft surface. This helps verify, or improve, the

  17. Combustion Process Modelling and Control

    Directory of Open Access Journals (Sweden)

    Vladimír Maduda

    2007-10-01

    Full Text Available This paper deals with realization of combustion control system on programmable logic controllers. Control system design is based on analysis of the current state of combustion control systems in technological device of raw material processing area. Control system design is composed of two subsystems. First subsystem is represented by software system for measured data processing and for data processing from simulation of the combustion mathematical model. Outputs are parameters for setting of controller algorithms. Second subsystem consists from programme modules. The programme module is presented by specific control algorithm, for example proportional regulation, programmed proportional regulation, proportional regulation with correction on the oxygen in waste gas, and so on. According to the specific combustion control requirements it is possible built-up concrete control system by programme modules. The programme modules were programmed by Automation studio that is used for development, debugging and testing software for B&R controllers.

  18. In-situ combustion test on outcrops in Kramai oil field

    Energy Technology Data Exchange (ETDEWEB)

    Lang, S.

    1982-01-01

    An in-situ combustion test was performed in Kramai oil field, located in the northwestern border of the Zhungerer Basin, China. The main objectives of the test were to investigate directly the reservoir geology, the petrophysical properties of the reservoir rock, and the flow properties of oil, gas and water within the reservoir. The paper describes the test procedure, including the well pattern, the test pit, operation and inspection techniques, etc., and presents a general discussion of the results obtained.

  19. Combustion synthesis of advanced materials. [using in-situ infiltration technique

    Science.gov (United States)

    Moore, J. J.; Feng, H. J.; Perkins, N.; Readey, D. W.

    1992-01-01

    The combustion synthesis of ceramic-metal composites using an in-situ liquid infiltration technique is described. The effect of varying the reactants and their stoichiometry to provide a range of reactant and product species i.e. solids, liquids and gases, with varying physical properties e.g. thermal conductivity, on the microstructure and morphology of synthesized products is also described. Alternatively, conducting the combustion synthesis reaction in a reactive gas environment is also discussed, in which advantages can be gained from the synergistic effects of combustion synthesis and vapor phase transport. In each case, the effect of the presence or absence of gravity (density) driven fluid flow and vapor transport is discussed as is the potential for producing new and perhaps unique materials by conducting these SHS reactions under microgravity conditions.

  20. Computer modeling of fluid flow and combustion in the ISV (In Situ Vitrification) confinement hood

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R.W.; Paik, S.

    1990-09-01

    Safety and suitability objectives for the application of the In Situ Vitrification (ISV) technology at the INEL require that the physical processes involved in ISVV be modeled to determine their operational behavior. The mathematical models that have been determined to address the modeling needs adequately for the ISV analysis package are detailed elsewhere. The present report is concerned with the models required for simulating the reacting flow that occurs in the ISV confinement hood. An experimental code named COYOTE has been secured that appears adequate to model the combustion in the confinement hood. The COYOTE code is a two-dimensional, transient, compressible, Eulerian, gas dynamics code for modeling reactive flows. It recognizes nonuniform Cartesian and cylindrical geometry and is based on the ICE (Implicit Continuous-fluid Eulerian) family of solution methods. It includes models for chemical reactions based on chemical kinetics as well as equilibrium chemistry. The mathematical models contained in COYOTE, their discrete analogs, the solution procedure, code structure and some test problems are presented in the report. 12 refs., 17 figs., 6 tabs.

  1. Experimental forward and reverse in situ combustion gasification of lignite with production of hydrogen-rich syngas

    Institute of Scientific and Technical Information of China (English)

    Yong Cui; Jie Liang; Zhangqing Wang; Xiaochun Zhang; Chenzi Fan; Xuan Wang

    2014-01-01

    This research focused on the feasibility of applying the forward and reverse combustion approach to the in situ gasification of lignite with the production of hydrogen-rich syngas (H2 and CO). The so-called forward combustion gasification (FCG) and reverse combustion gasification (RCG) approach in which oxygen and steam are simultaneously fed to the simulated system of underground coal gasification (UCG) was studied. A simulated system of UCG was designed and established. The underground conditions of the coal seam and strata were simulated in the system. The combustion gasification of lignite has been carried out experimentally for almost 6.5 days. The average effective content (H2 ? CO) of syngas during the FCG phase was 62.31%and the maximum content was 70.92%. For the RCG phase the corresponding figures are 61.33%and 67.91%. Thus, the feasibility of using RCG way for UCG has been demonstrated. The temperature profiles have been provided by using of 85 thermocouples during the model experiment, which portrayed the several nephograms of thermal data in the gasifier were of significance for the prospective gasification processes.

  2. IN SITU FIELD TESTING OF PROCESSES

    Energy Technology Data Exchange (ETDEWEB)

    J.S.Y. YANG

    2004-11-08

    The purpose of this scientific analysis report is to update and document the data and subsequent analyses from ambient field-testing activities performed in underground drifts and surface-based boreholes through unsaturated zone (UZ) tuff rock units. In situ testing, monitoring, and associated laboratory studies are conducted to directly assess and evaluate the waste emplacement environment and the natural barriers to radionuclide transport at Yucca Mountain. This scientific analysis report supports and provides data to UZ flow and transport model reports, which in turn contribute to the Total System Performance Assessment (TSPA) of Yucca Mountain, an important document for the license application (LA). The objectives of ambient field-testing activities are described in Section 1.1. This report is the third revision (REV 03), which supercedes REV 02. The scientific analysis of data for inputs to model calibration and validation as documented in REV 02 were developed in accordance with the Technical Work Plan (TWP) ''Technical Work Plan for: Performance Assessment Unsaturated Zone'' (BSC 2004 [DIRS 167969]). This revision was developed in accordance with the ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Section 1.2.4) for better integrated, consistent, transparent, traceable, and more complete documentation in this scientific analysis report and associated UZ flow and transport model reports. No additional testing or analyses were performed as part of this revision. The list of relevant acceptance criteria is provided by ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654]), Table 3-1. Additional deviations from the TWP regarding the features, events, and processes (FEPs) list are discussed in Section 1.3. Documentation in this report includes descriptions of how, and under what

  3. Combustion Chemistry Diagnostics for Cleaner Processes.

    Science.gov (United States)

    Kohse-Höinghaus, Katharina

    2016-09-12

    Climate change, environmental problems, urban pollution, and the dependence on fossil fuels demand cleaner, renewable energy strategies. However, they also ask for urgent advances in combustion science to reduce emissions. For alternative fuels and new combustion regimes, crucial information about the chemical reactions from fuel to exhaust remains lacking. Understanding such relations between combustion process, fuel, and emissions needs reliable experimental data from a wide range of conditions to provide a firm basis for predictive modeling of practical combustion processes.

  4. Study on Analogy Theory of Physical Simulation of In - situ Combustion%火烧油层物理模拟相似原理研究

    Institute of Scientific and Technical Information of China (English)

    刘其成; 程海清; 张勇; 赵庆辉; 刘宝良

    2013-01-01

    根据火烧油层燃烧特征,提出一种表征稠油燃烧过程参与反应的四相七组分化学动力学关系式,建立了描述火烧油层采油过程中质变、传质、传热数学模型.采用无因次处理及量纲分析方法,推导出较为完整的火烧油层物理模拟相似准则数群,示例了3种条件下的相似准则数,并对其适应性进行了分析.该研究可用于指导火烧油层物理模拟实验研究工作.%The kinetics relations of 4 - phase 7 - component that participates chemical reaction during heavy oil combustion is raised and the mathematical models of mass variation, mass transfer and heat transfer that describe in - situ combustion during production are established based on the characteristics of in - situ combustion. The relatively complete group number of analogy criteria of physical simulation of in - situ combustion is derived, analogy criterion number under 3 conditions is demonstrated and the adaptability to the criterion number is analyzed by using dimensionless process and dimension analyses. The study results can be used to guide experimental study of physical simulation of in - situ combustion.

  5. Master of Puppets: Cooperative Multitasking for In Situ Processing

    Energy Technology Data Exchange (ETDEWEB)

    Morozov, Dmitriy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lukic, Zarija [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-01-01

    Modern scientific and engineering simulations track the time evolution of billions of elements. For such large runs, storing most time steps for later analysis is not a viable strategy. It is far more efficient to analyze the simulation data while it is still in memory. Here, we present a novel design for running multiple codes in situ: using coroutines and position-independent executables we enable cooperative multitasking between simulation and analysis, allowing the same executables to post-process simulation output, as well as to process it on the fly, both in situ and in transit. We present Henson, an implementation of our design, and illustrate its versatility by tackling analysis tasks with different computational requirements. This design differs significantly from the existing frameworks and offers an efficient and robust approach to integrating multiple codes on modern supercomputers. The techniques we present can also be integrated into other in situ frameworks.

  6. Adaptation of in-situ microscopy for crystallization processes

    Science.gov (United States)

    Bluma, A.; Höpfner, T.; Rudolph, G.; Lindner, P.; Beutel, S.; Hitzmann, B.; Scheper, T.

    2009-08-01

    In biotechnological and pharmaceutical engineering, the study of crystallization processes gains importance. An efficient analytical inline sensor could help to improve the knowledge about these processes in order to increase efficiency and yields. The in-situ microscope (ISM) is an optical sensor developed for the monitoring of bioprocesses. A new application for this sensor is the monitoring in downstream processes, e.g. the crystallization of proteins and other organic compounds. This contribution shows new aspects of using in-situ microscopy to monitor crystallization processes. Crystals of different chemical compounds were precipitated from supersaturated solutions and the crystal growth was monitored. Exemplified morphological properties and different forms of crystals could be distinguished on the basis of offline experiments. For inline monitoring of crystallization processes, a special 0.5 L stirred tank reactor was developed and equipped with the in-situ microscope. This reactor was utilized to carry out batch experiments for crystallizations of O-acetylsalicyclic acid (ASS) and hen egg white lysozyme (HEWL). During the whole crystallization process, the in-situ microscope system acquired images directly from the crystallization broth. For the data evaluation, an image analysis algorithm was developed and implemented in the microscope analysis software.

  7. Fine and Ultrafine Particles from Combustion Sources - Investigations with in-situ techniques

    Energy Technology Data Exchange (ETDEWEB)

    Pagels, Joakim

    2005-04-01

    Fine airborne particles are associated with adverse health effects in the human population. The aim of this research was to develop and evaluate methods for in-situ characterisation of fine and ultrafine particles and to determine their deposition in the human airways. The aim was also to increase knowledge about health and environmentally relevant properties of aerosols from biomass combustion and selected indoor sources. The methods include instrumental techniques such as Scanning Mobility Particle Sizer (SMPS), Electrical Low-Pressure Impactor (ELPI), Aerodynamic Particle Sizer (APS) and Tandem Differential Mobility Analysers (TDMA) based on volatility and hygroscopic growth. Filter samplers and impactors were used for collecting particles on substrates for subsequent chemical analysis. Emissions from local district heating plants (0.5-12 MW), based on moving grate combustion of woody fuels, were sampled with a dilution system and characterised. Particles from the indoor sources of cigarettes, incense and candles were examined in the laboratory by using an airtight 22 m{sup 3} stainless steel chamber. A set-up to determine respiratory deposition in humans was constructed. It was automatised and uses an electrical mobility spectrometer with an improved inversion algorithm to perform fast measurements of particles of different sizes in the inhaled and exhaled air. It was evaluated on human test-persons. The investigated biomass combustion sources emit high concentrations of fine and ultrafine particles. The chemical composition is dominated by KCl and K{sub 2}SO{sub 4}; Zn, Cd and Pb were also quantified. Elemental carbon was identified in particles larger than 150 nm during periods of incomplete combustion. The particle concentration depends on the fuel ash content and the combustion efficiency. The aerosol is essentially internally mixed with hygroscopic growth factors significantly higher than reported for diesel exhaust and environmental tobacco smoke. The

  8. Study on Mathematical Models of the Reaction of In - situ Combustion%火烧油层燃烧反应数学模型研究

    Institute of Scientific and Technical Information of China (English)

    张方礼; 刘其成; 赵庆辉; 张勇; 程海清

    2012-01-01

    Mathematical models of combustion kinetics of three - dimensional four phases and seven components are established and the formulae of pyrolyzation and oxidization of all conponents of crude oil are derived under conditions of porous media in view of the properties of reservoir in - situ combustion,using Arrhenius formula and adopting fuel conversion percentage. The relationships between mass transfer and phase equilibrium among all components are established by means of double - film theory and both mass conservation equation and energy conservation equation for the combustion process of in - situ combustion are also established based on the relationship of molecular diffusion and convective - dispersive of all components in porous medium,thus providing reliable bases for the physical simulation of in - situ combustion and field test design.%针对稠油油藏火烧油层特点,利用Arrhenius公式,采用燃料转化率方法,建立了火烧油层三维四相七组分燃烧动力学模型,推导出多孔介质条件下原油各组分热解与氧化反应速率表达式.通过双膜理论解决了各组分在相间的质量传递及相平衡关系,并根据各组分在多孔介质中分子扩散与对流弥散关系,建立了火烧油层燃烧过程中各组分的质量、能量守恒方程,为火烧油层物理模拟、数值模拟及现场试验方案设计提供了可靠的依据.

  9. A Pore-Network Model of In-Situ Combustion in Porous Media

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Chuan; Yortsos, Y.C.

    2001-01-29

    This report the use of dual pore networks (pores and solid sites) for modeling the effect of the microstructure on combustion processes in porous media is considered. The model accounts for flow and transport of the gas phase in the porespace, where convection predominates, and for heat transfer by conduction in the solid phase. Gas phase flow in the pore and throats is governed by Darcy's law.

  10. In-situ UV-Raman study on soot combustion over TiO2 or ZrO2-supported vanadium oxide catalysts

    Institute of Scientific and Technical Information of China (English)

    WACHS; Israel; E.

    2008-01-01

    UV-Raman spectroscopy was used to study the molecular structures of TiO2 or ZrO2-supported vana-dium oxide catalysts.The real time reaction status of soot combustion over these catalysts was de-tected by in-situ UV-Raman spectroscopy.The results indicate that TiO2 undergoes a crystalline phase transformation from anatase to rutile phase with the increasing of reaction temperature.However,no obvious phase transformation process is observed for ZrO2 support.The structures of supported va-nadium oxides also depend on the V loading.The vanadium oxide species supported on TiO2 or ZrO2 attain monolayer saturation when V loading is equal to 4(4 is the number of V atoms per 100 support metal ions).Interestingly,this loading ratio(V4/TiO2 and V4/ZrO2) gave the best catalytic activities for soot combustion reaction on both supports(TiO2 and ZrO2).The formation of surface oxygen com-plexes(SOC) is verified by in-situ UV Raman spectroscopy and the SOC mainly exist as carboxyl groups during soot combustion.The presence of NO in the reaction gas stream can promote the pro-duction of SOC.

  11. In-situ UV-Raman study on soot combustion over TiO2 or ZrO2-supported vanadium oxide catalysts

    Institute of Scientific and Technical Information of China (English)

    LIU Jian; ZHAO Zhen; XU ChunMing; DUAN AiJun; JIANG GuiYuan; GAO JinSen; LIN WenYong; WACHS Israel E.

    2008-01-01

    UV-Raman spectroscopy was used to study the molecular structures of TiO2 or ZrO2-supported vana- dium oxide catalysts. The real time reaction status of soot combustion over these catalysts was de-tected by in-situ UV-Raman spectroscopy. The results indicate that TiO= undergoes a crystalline phase transformation from anatase to futile phase with the increasing of reaction temperature. However, no obvious phase transformation process is observed for ZrO2 support. The structures of supported va-nadium oxides also depend on the V loading. The vanadium oxide species supported on TiO2 or ZrO2 attain monolayer saturation when V loading is equal to 4 (4 is the number of V atoms per 100 support metal ions). Interestingly, this loading ratio (V4/TiO2 and V4/ZrO2) gave the best catalytic activities for soot combustion reaction on both supports (TiO2 and ZrO2). The formation of surface oxygen com-plexes (SOC) is verified by in-situ UV Raman spectroscopy and the SOC mainly exist as carboxyl groups during soot combustion. The presence of NO in the reaction gas stream can promote the pro-duction of SOC.

  12. THE USE OF COAL COMBUSTION BY-PRODUCTS FOR IN SITU TREATMENT OF ACID MINE DRAINAGE

    Energy Technology Data Exchange (ETDEWEB)

    Geoffrey A. Canty; Jess W. Everett

    2004-09-30

    In 1994 a demonstration project was undertaken to investigate the effectiveness of using CCBs for the in situ treatment of acidic mine water. Actual injection of alkaline material was performed in 1997 with initial positive results; however, the amount of alkalinity added to the system was limited and resulted in short duration treatment. In 1999, a CBRC grant was awarded to further investigate the effectiveness of alkaline injection technology (AIT). Funds were released in fall 2001. In December 2001, 2500 tons of fluidized bed combustion (FBC) ash were injected into the wells used in the 1997 injection project. Post injection monitoring continued for 24 months. During this period the mine chemistry had gone through a series of chemical changes that manifested as stages or ''treatment phases.'' The mine system appeared to be in the midst of reestablishing equilibrium with the partial pressure of mine headspace. Alkalinity and pH appeared to be gradually increasing during this transition. As of December 2003, the pH and alkalinity were roughly 7.3 and 65 ppm, respectively. Metal concentrations were significantly lower than pre-injection levels, but iron and manganese concentrations appeared to be gradually increasing (roughly 30 ppm and 1.25 ppm, respectively). Aluminum, nickel, and zinc were less than pre-injection concentrations and did not appear to be increasing (roughly

  13. Method for establishing a combustion zone in an in situ oil shale retort having a pocket at the top

    Science.gov (United States)

    Cha, Chang Y.

    1980-01-01

    An in situ oil shale retort having a top boundary of unfragmented formation and containing a fragmented permeable mass has a pocket at the top, that is, an open space between a portion of the top of the fragmented mass and the top boundary of unfragmented formation. To establish a combustion zone across the fragmented mass, a combustion zone is established in a portion of the fragmented mass which is proximate to the top boundary. A retort inlet mixture comprising oxygen is introduced to the fragmented mass to propagate the combustion zone across an upper portion of the fragmented mass. Simultaneously, cool fluid is introduced to the pocket to prevent overheating and thermal sloughing of formation from the top boundary into the pocket.

  14. Development of the integrated in situ lasagna process

    Energy Technology Data Exchange (ETDEWEB)

    Ho, S.; Athmer, C.; Sheridan, P. [Monsanto Company, St. Louis, MO (United States)] [and others

    1995-10-01

    Contamination in deep, low permeability soils poses a significant technical challenge to in-situ remediation efforts. Poor accessibility to the contaminants and difficulty in uniform delivery of treatment reagents have rendered existing in-situ methods such as bioremediation, vapor extraction, and pump and treat rather ineffective when applied to low permeability soils present at many contaminated sites. Recently the use of electrokinetics as an in situ method for soil remediation has received increasing attention due to its unique applicability to low-permeability soils. Electrokinetics includes the transport of water (electroosmosis) as well as ions (electromigration) as a result of an applied electric field. For remedial applications, water is typically introduced into the soil at the anode to replenish the water flowing towards the cathode due to electroosmosis. The water flow is utilized to flush organic contaminants from the subsurface soil to the ground surface at the cathode region for further treatment or disposal. This report describes a treatment process under development termed the LASAGNA process which incorporates electrokinetics, along with the establishment of degradation zones, for pollutant removal.

  15. In-situ biogas upgrading process: modeling and simulations aspects

    DEFF Research Database (Denmark)

    Lovato, Giovanna; Alvarado-Morales, Merlin; Kovalovszki, Adam

    2017-01-01

    Biogas upgrading processes by in-situ hydrogen (H2) injection are still challenging and could benefit from a mathematical model to predict system performance. Therefore, a previous model on anaerobic digestion was updated and expanded to include the effect of H2 injection into the liquid phase...... considering a set of Case Studies. Biogas composition and H2 utilization were correctly predicted, with overall deviation below 10% compared to experimental measurements. Parameter sensitivity analysis revealed that the model is highly sensitive to the H2 injection rate and mass transfer coefficient....... The model developed is an effective tool for predicting process performance in scenarios with biogas upgrading....

  16. Chattanooga shale: uranium recovery by in situ processing

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, D.D.

    1977-04-25

    The increasing demand for uranium as reactor fuel requires the addition of sizable new domestic reserves. One of the largest potential sources of low-grade uranium ore is the Chattanooga shale--a formation in Tennessee and neighboring states that has not been mined conventionally because it is expensive and environmentally disadvantageous to do so. An in situ process, on the other hand, might be used to extract uranium from this formation without the attendant problems of conventional mining. We have suggested developing such a process, in which fracturing, retorting, and pressure leaching might be used to extract the uranium. The potential advantages of such a process are that capital investment would be reduced, handling and disposing of the ore would be avoided, and leaching reagents would be self-generated from air and water. If successful, the cost reductions from these factors could make the uranium produced competitive with that from other sources, and substantially increase domestic reserves. A technical program to evaluate the processing problems has been outlined and a conceptual model of the extraction process has been developed. Preliminary cost estimates have been made, although it is recognized that their validity depends on how successfully the various processing steps are carried out. In view of the preliminary nature of this survey (and our growing need for uranium), we have urged a more detailed study on the feasibility of in situ methods for extracting uranium from the Chattanooga shale.

  17. Claus recycle with double combustion process

    Energy Technology Data Exchange (ETDEWEB)

    El-Bishtawi, Ribhi; Haimour, No' man [University of Jordan, Amman 11942 (Jordan)

    2004-12-15

    A new modification is developed on conventional Claus process to increase the overall sulfur recovery as well as to decrease the costs. The modification combines both oxygen enrichment and recycling. The process is simulated and studied for various N{sub 2}/O{sub 2} ratios with and without using SURE double combustion technique. The predictions show that using pure oxygen in combustion, condensing water vapor in a condenser following the first sulfur condenser and recycling the effluent gas to combine it with fresh acid gas feed leads to large savings in the production cost and to a clean environment. However, it leads to a high adiabatic flame temperature which exceeds the maximum allowable temperature of the furnace material of construction as well as its refractory. To avoid these effects, it is necessary to use SURE double combustion technique. The oxygen flow rate to the first combustion stage should not exceed 78% O{sub 2}.

  18. Computation of combustion and gasifying processes

    Energy Technology Data Exchange (ETDEWEB)

    Kozaczaka, J. [Univ. of Mining and Metallurgy, Krakow, Faculty of Mechanical Engineering and Robotics (Poland); Horbaj, P. [Kosice Univ., Dept. of Power Engineering (Poland)

    2003-08-01

    Engineer computation methods of combustion and gasifying processes, their application and taking into account NO{sub x} and SO{sub x} contents in resulting gases using chemical equilibrium considerations. The paper deals with stoichiometric calculation of combustion processes with equilibrium on the side of products; with calculations of gasifying processes and with calculations of quasi - equilibrium processes. The main part of the article is oriented on problem - directional equilibrium combustion calculation. The engineer calculation methods of fuel conversion processes presented in this paper can be applied for thermodynamic analyses of complex power systems wherever the heat supply has been assumed in hitherto considerations. It will make these analyses more reliable and closer to the real conditions. (orig.)

  19. A Sensor System Based on Semi-Conductor Metal Oxide Technology for In Situ Detection of Coal Fired Combustion Gases

    Energy Technology Data Exchange (ETDEWEB)

    Brent Marquis

    2007-05-31

    Sensor Research and Development Corporation (SRD) proposed a two-phase program to develop a robust, autonomous prototype analyzer for in situ, real-time detection, identification, and measurement of coal-fired combustion gases and perform field-testing at an approved power generation facility. SRD developed and selected sensor materials showing selective responses to carbon monoxide, carbon dioxide, nitric oxide, nitrogen dioxide, ammonia, sulfur dioxide and hydrogen chloride. Sensor support electronics were also developed to enable prototype to function in elevated temperatures without any issues. Field-testing at DOE approved facility showed the ability of the prototype to detect and estimate the concentration of combustion by-products accurately with relatively low false-alarm rates at very fast sampling intervals.

  20. In situ studies of microbial inactivation during high pressure processing

    Science.gov (United States)

    Maldonado, Jose Antonio; Schaffner, Donald W.; Cuitiño, Alberto M.; Karwe, Mukund V.

    2016-01-01

    High pressure processing (HPP) has been shown to reduce microbial concentration in foods. The mechanisms of microbial inactivation by HPP have been associated with damage to cell membranes. The real-time response of bacteria to HPP was measured to elucidate the mechanisms of inactivation, which can aid in designing more effective processes. Different pressure cycling conditions were used to expose Enterobacter aerogenes cells to HPP. Propidium iodide (PI) was used as a probe, which fluoresces after penetrating cells with damaged membranes and binding with nucleic acids. A HPP vessel with sapphire windows was used for measuring fluorescence in situ. Membrane damage was detected during pressurization and hold time, but not during depressurization. The drop in fluorescence was larger than expected after pressure cycles at higher pressure and longer times. This indicated possible reversible disassociation of ribosomes resulting in additional binding of PI to exposed RNA under pressure and its release after depressurization.

  1. Design aspects to consider during drilling and completion of wells of the pilot test in the in situ combustion project, Bare field

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, D.; Garcia, J. [PDVSA Petroleos de Venezuela SA, Caracas (Venezuela, Bolivarian Republic of). Exploration and Production; PDVSA Petroleos de Venezuela SA, Caracas (Venezuela, Bolivarian Republic of). INTEVEP; Rodriguez, J.; Reverol, H. [PDVSA Petroleos de Venezuela SA, Caracas (Venezuela, Bolivarian Republic of). Exploration and Production

    2009-07-01

    This paper discussed an in situ combustion demonstration project in Venezuela's Orinoco oil belt. Unconventional drilling and completion techniques are being implemented in order to assess well performance during different phases of the combustion process. Drilling, well completion and monitoring techniques planned in each of the project's wells were described. The purpose of the project is to minimize formation damage, reduce corrosion, and prevent formation sand production. Numerical analyses, sampling studies, and laboratory experiments will be conducted in order to define well arrangement and to select completion equipment. Thermocouples, pressure chambers, and fiber optics will be used to monitor temperature and pressure rates. To date, the analyses have demonstrated that the horizontal section of the production wells must be drilled with special directional and geo-navigational tools. The selected completion equipment must allow for the installation of high capacity mechanical pumping systems. Completion equipment must be capable of performing in high temperatures and with the corrosive gases produced during the combustion process. It was concluded that casings for the wells must be centralized in order to ensure good cement placement. Real time monitoring will be conducted to control firefloods. 3 refs., 1 tab., 8 figs.

  2. In-Situ Optical Diagnostics Of Diesel Spray Injection And Combustion For Engine-Like Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Dreier, T.; Gerber, T.

    2005-03-01

    Serial imaging of spray propagation, soot blackbody radiation and flame chemiluminescence measurements were performed to characterize the propagation and combustion of Diesel fuel sprays in the PSI high temperature pressure vessel (HTDZ). (author)

  3. Analysis of rocket engine injection combustion processes

    Science.gov (United States)

    Salmon, J. W.

    1976-01-01

    A critique is given of the JANNAF sub-critical propellant injection/combustion process analysis computer models and application of the models to correlation of well documented hot fire engine data bases. These programs are the distributed energy release (DER) model for conventional liquid propellants injectors and the coaxial injection combustion model (CICM) for gaseous annulus/liquid core coaxial injectors. The critique identifies model inconsistencies while the computer analyses provide quantitative data on predictive accuracy. The program is comprised of three tasks: (1) computer program review and operations; (2) analysis and data correlations; and (3) documentation.

  4. Advanced Fuels and Combustion Processes for Propulsion

    Science.gov (United States)

    2010-09-01

    production from biomass steam reforming – Conduct a feasibility analysis of the proposed integrated process Energia Technologies - D. Nguyen & K. Parimi...strength foam material development by Ultramet – Combustion experiments performed U. Of Alabama – End-user input provided by Solar Turbines Major

  5. In situ silica-EPDM nanocomposites obtained via reactive processing

    NARCIS (Netherlands)

    Miloskovska, Elena; Hristova-Bogaerds, Denka; van Duin, Martin; de With, Gijsbertus

    2015-01-01

    In situ rubber nanocomposites prepared via reactive batch mixing and via reactive extrusion were studied. Materials produced via reactive batch mixing showed a significantly higher silica content for a similar reaction time as compared to previously prepared in situ nanocomposites using a diffusion

  6. Diode laser supported in situ detection of O{sub 2} and alkali atoms for optimization of high-temperature combustion of coal dust and toxic waste as well as fire extinction; Diodenlaser-gestuetzter in-situ-Nachweis von O{sub 2} und Alkaliatomen zur Optimierung der Hochtemperaturkohlenstaub- und Sondermuellverbrennung sowie der Brandbekaempfung

    Energy Technology Data Exchange (ETDEWEB)

    Schlosser, E.

    2002-07-01

    The author investigated sensitive in situ detection using TDLAS of high-reactive alkali atoms and molecular oxygen in the conditions of industrial combustion processes (high dust concentrations, high pressure, high temperature) and in the optically difficult conditions of fire extinction, i.e. two cases in which it is impossible to take samples. [German] Ziel dieser Arbeit war der empfindliche In-situ-Nachweis mit TDLAS (direkte Absorptionsspektroskopie mit abstimmbaren Diodenlasern) von hochreaktiven Alkaliatomen sowie molekularem Sauerstoff unter den Bedingungen von industriellen Verbrennungsprozessen (hoher Staubgehalt, Druck und Temperatur) sowie unter den optisch anspruchsvollen Bedingungen einer Feuerloeschung. In beiden Faellen ist es nicht moeglich, die gesuchte Konzentration durch eine Probenahme zu ermitteln. (orig.)

  7. Unsteady Processes in Solid Propellant Combustion,

    Science.gov (United States)

    1977-05-01

    0—AflO ~5a INSTITUTO NACIONAL DE TECNICA AEROESPACIAL MADRID (SPAIN) F/S 21/9.2UNSTEADY PROCESSES IN SOLID PROPELLANT COMBUSTION . (U) MAY...PRO C E SS E S IN SOLID P R O P E L L A N T C O M B U S T I O N H A. Crespo and M. Kindelán Instituto Nacional de Técnica Aeroespacial Madrid , Spain j

  8. In situ characterization of nanoscale catalysts during anodic redox processes

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Renu [National Institute of Standards and Technology; Crozier, Peter [Arizona State University; Adams, James [Arizona State University

    2013-09-19

    Controlling the structure and composition of the anode is critical to achieving high efficiency and good long-term performance. In addition to being a mixed electronic and ionic conductor, the ideal anode material should act as an efficient catalyst for oxidizing hydrogen, carbon monoxide and dry hydrocarbons without de-activating through either sintering or coking. It is also important to develop novel anode materials that can operate at lower temperatures to reduce costs and minimized materials failure associated with high temperature cycling. We proposed to synthesize and characterize novel anode cermets materials based on ceria doped with Pr and/or Gd together with either a Ni or Cu metallic components. Ceria is a good oxidation catalyst and is an ionic conductor at room temperature. Doping it with trivalent rare earths such as Pr or Gd retards sintering and makes it a mixed ion conductor (ionic and electronic). We have developed a fundamental scientific understanding of the behavior of the cermet material under reaction conditions by following the catalytic oxidation process at the atomic scale using a powerful Environmental Scanning Transmission Electron Microscope (ESTEM). The ESTEM allowed in situ monitoring of structural, chemical and morphological changes occurring at the cermet under conditions approximating that of typical fuel-cell operation. Density functional calculations were employed to determine the underlying mechanisms and reaction pathways during anode oxidation reactions. The dynamic behavior of nanoscale catalytic oxidation of hydrogen and methane were used to determine: ? Fundamental processes during anodic reactions in hydrogen and carbonaceous atmospheres ? Interfacial effects between metal particles and doped ceria ? Kinetics of redox reaction in the anode material

  9. Thermodynamic analysis of in situ gasification-chemical looping combustion (iG-CLC) of Indian coal.

    Science.gov (United States)

    Suresh, P V; Menon, Kavitha G; Prakash, K S; Prudhvi, S; Anudeep, A

    2016-10-01

    Chemical looping combustion (CLC) is an inherent CO2 capture technology. It is gaining much interest in recent years mainly because of its potential in addressing climate change problems associated with CO2 emissions from power plants. A typical chemical looping combustion unit consists of two reactors-fuel reactor, where oxidation of fuel occurs with the help of oxygen available in the form of metal oxides and, air reactor, where the reduced metal oxides are regenerated by the inflow of air. These oxides are then sent back to the fuel reactor and the cycle continues. The product gas from the fuel reactor contains a concentrated stream of CO2 which can be readily stored in various forms or used for any other applications. This unique feature of inherent CO2 capture makes the technology more promising to combat the global climate changes. Various types of CLC units have been discussed in literature depending on the type of fuel burnt. For solid fuel combustion three main varieties of CLC units exist namely: syngas CLC, in situ gasification-CLC (iG-CLC) and chemical looping with oxygen uncoupling (CLOU). In this paper, theoretical studies on the iG-CLC unit burning Indian coal are presented. Gibbs free energy minimization technique is employed to determine the composition of flue gas and oxygen carrier of an iG-CLC unit using Fe2O3, CuO, and mixed carrier-Fe2O3 and CuO as oxygen carriers. The effect of temperature, suitability of oxygen carriers, and oxygen carrier circulation rate on the performance of a CLC unit for Indian coal are studied and presented. These results are analyzed in order to foresee the operating conditions at which economic and smooth operation of the unit is expected.

  10. Electrochemical atomic force microscopy: In situ monitoring of electrochemical processes

    Science.gov (United States)

    Reggente, Melania; Passeri, Daniele; Rossi, Marco; Tamburri, Emanuela; Terranova, Maria Letizia

    2017-08-01

    The in-situ electrodeposition of polyaniline (PANI), one of the most attractive conducting polymers (CP), has been monitored performing electrochemical atomic force microscopy (EC-AFM) experiments. The electropolymerization of PANI on a Pt working electrode has been observed performing cyclic voltammetry experiments and controlling the evolution of current flowing through the electrode surface, together with a standard AFM image. The working principle and the potentialities of this emerging technique are briefly reviewed and factors limiting the studying of the in-situ electrosynthesis of organic compounds discussed.

  11. Gas injection to inhibit migration during an in situ heat treatment process

    Energy Technology Data Exchange (ETDEWEB)

    Kuhlman, Myron Ira (Houston, TX); Vinegar; Harold J. (Bellaire, TX); Baker, Ralph Sterman (Fitchburg, MA); Heron, Goren (Keene, CA)

    2010-11-30

    Methods of treating a subsurface formation are described herein. Methods for treating a subsurface treatment area in a formation may include introducing a fluid into the formation from a plurality of wells offset from a treatment area of an in situ heat treatment process to inhibit outward migration of formation fluid from the in situ heat treatment process.

  12. Effect of Variant End of Injection Period on Combustion Process of Biodiesel Combustion

    Directory of Open Access Journals (Sweden)

    Khalid Amir

    2016-01-01

    Full Text Available Biodiesel is an alternative fuel as a replacement to the standard diesel fuel in combustion diesel engine. The biodiesel fuel has a significantly influences throughout the combustion process and exhaust emission. The purpose of this research is to investigate the combustion process behavior during the End of Injection (EOI period and operates under variant conditions using Rapid Compression Machine (RCM. Experimental of RCM is used to simulate a combustion process and combustion characteristics of diesel engine combustion. Three types of biodiesel blend which are B5, B10 and B15 were tested at several injection pressures of 80 MPa, 90 MPa and 130 MPa under different ambient temperatures, 750 K to 1100 K. The results of this study showed that the ignition delay slightly reduced with increasing the content of biodiesel blends from B5, B10 and B15 and became more shorten as the injection pressure been enhanced. As the injection pressure increased, the behavior of combustion pressure at end of injection is reduced, radically increased the NOX emission. It is noted that the process of combustion at the end of injection increased as the ambient temperature is rising. In fact, higher initial ambient temperature improved the fuel atomization and mixing process. Under the biodiesel combustion with higher ambient temperature condition, the exhaust emission of CO, O2, and HC became less but increased in NOX emission. Besides, increased in blends of biodiesel ratio are found to enhance the combustion process, resulted a decreased in HC emissions.

  13. Understanding the thermal sciences in the electron beam melting process through in-situ process monitoring

    Science.gov (United States)

    Raplee, J.; Plotkowski, A.; Kirka, M. M.; Dinwiddie, R.; Dehoff, R. R.; Babu, S. S.

    2017-04-01

    Additive Manufacturing provides the opportunity to fabricate components of nearly limitless complexity compared to that of traditional manufacturing techniques. However, thermal gyrations imparted into the material from the passing of the heat source cause challenges in fabricating complex structures with the proper process parameters. While the thermal history of the material can be simulated, validating the simulations requires access to thermal data generated through in-situ process monitoring. While generation of in-situ thermal data seems trivial, acquiring and developing reliable calibrations for metallic materials is difficult due to the physical state of the material transitioning from powder to liquid to a solid. To be discussed is the methodology taken to integrate IR in-situ process monitoring within the electron beam melting process and the approach developed to accurately correlate a materials emissivity to temperature during the build process. Further the wealth of information contained within the thermal data will be discussed in the context of understanding of microstructural evolutions within the material during the build process, identification of material defects, and ability to determining the similarity/repeatability of builds fabricated with identical processing parameters as based only on the thermal signature of the build.

  14. Online, In-Situ Monitoring Combustion Turbines Using Wireless Passive Ceramic Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Xun; An, Linan; Xu, Chengying

    2013-06-30

    The overall objective of this project is to develop high-temperature wireless passive ceramic sensors for online, real-time monitoring combustion turbines. During this project period, we have successfully demonstrated temperature sensors up to 1300{degrees}C and pressure sensors up to 800oC. The temperature sensor is based on a high-Q-factor dielectric resonator and the pressure sensor utilizes the evanescent-mode cavity to realize a pressure-sensitive high-Q-factor resonator. Both sensors are efficiently integrated with a compact antenna. These sensors are wirelessly interrogated. The resonant frequency change corresponding to either temperature or pressure can be identified using a time-domain gating technique. The sensors realized in this project can survive harsh environments characterized by high temperatures (>1000{degrees}C) and corrosive gases, owing to the excellent material properties of polymer-derived ceramics (PDCs) developed at University of Central Florida. It is anticipated that this work will significantly advance the capability of high-temperature sensor technologies and be of a great benefit to turbine industry and their customers.

  15. In situ synthesis of NiAl-NbB{sub 2} composite powder through combustion synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Shokati, Ali Akbar, E-mail: ali_shokati@aut.ac.ir [Department of Mining and Metallurgical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran 1591634311 (Iran, Islamic Republic of); Parvin, Nader, E-mail: nparvin@aut.ac.ir [Department of Mining and Metallurgical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran 1591634311 (Iran, Islamic Republic of); Sabzianpour, Naser, E-mail: naser_sabz@yahoo.com [Department of Mining and Metallurgical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran 1591634311 (Iran, Islamic Republic of); Shokati, Mohammad, E-mail: mohammad_shokaty14@yahoo.com [Faculty of Mechanical Engineering, K.N. Toosi University of Technology, P.O. Box: 19395-1999, Tehran (Iran, Islamic Republic of); Hemmati, Ali, E-mail: ali19he@gmail.com [Department of Mining and Metallurgical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran 1591634311 (Iran, Islamic Republic of)

    2013-02-05

    Highlights: Black-Right-Pointing-Pointer A Novel NiAl matrix composite powder with 0-40 wt.% NbB{sub 2} was synthesized. Black-Right-Pointing-Pointer Composite powders were synthesized by thermal explosion reaction of Ni-Al-Nb-B system. Black-Right-Pointing-Pointer Microhardness of NiAl considerably increased with raising NbB{sub 2} content. Black-Right-Pointing-Pointer Synthesized composite powders is a good candidate as precursor for thermal barrier application. - Abstract: Synthesis of a novel NiAl matrix composite powder reinforced with 0-40 wt.% NbB{sub 2} by combustion synthesis in thermal explosion mode was investigated. The elemental powders of Ni, Al, Nb, and amorphous boron were used as starting material. For all compositions final products consisted of only the NiAl and NbB{sub 2} phases. Coarser NbB{sub 2} with a relatively uniform distribution in NiAl matrix was formed with rising NbB{sub 2} content. Microhardness of NiAl considerably increased from 377 {+-} 13 HV{sub 0.05} to 866 {+-} 81 HV{sub 0.05} for NiAl with 40 wt.% NbB{sub 2}. High microhardness, proper size and distribution of NbB{sub 2} in NiAl matrix make it a good candidate as precursor for thermal spray application.

  16. IN SITU INTERFEROMETRIC STUDY ON THE GELATION PROCESS OF POLYACRYLIC ACID GELS

    Institute of Scientific and Technical Information of China (English)

    Ying Guan; Qiang Chen; Xian-min Zhang; Yu-xing Peng; Jian Xu

    2000-01-01

    In situ interferometry was used to investigate the gelation process of polyacrylic acid (PAA) gels. The basic principle of the in situ interferometry technique is illustrated. It can give sufficient information for non-destructive and successful investigation of the whole gelation process. The effect of initiator concentration on the gelation process was studied. The polymerization rate of AA increases with increasing initiator concentration. The error arising from the thermal effect in the gelation process can be neglected.

  17. Combustion-Driven Oscillation in Process Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Seebold, J.G. [Chevron Corporation (Retired), 198 James Avenue, Atherton, CA 94027 (United States)

    2005-10-15

    At this moment in thousands of process heaters all over the world there are, to borrow a phrase from the late Carl Sagan, 'billions and billions' of Btu/hr beneficially being released entirely free of pulsation. On those few occasions, perhaps a dozen and a half in my career, when I would get the inevitable 'Why me?' call, I have generally responsed with something like, 'Consider yourself lucky, you have a rare scientific curiosity on your hands'. Reflecting on the solutions ultimately found, I'm reminded that many years ago my friend Abbott Putnam shared with me an early AGA (American Gas Association) field-service bulletin that included a prescription for eliminating combustion-driven oscillations in home heating units; viz., 'Drill a hole; if that doesn't work, drill another hole' or words to that effect. Many times have I wished that I still had a copy of that bulletin and in this paper we will have occasion, once again, to reflect upon the value of that advice. In this paper we will discuss an instance that arose in a pioneering installation of a breakthrough development of 'extremely', to distinguish it from 'ultra', low-NOx lean premix burner technology. We will illustrate how, when and under what circumstances combustion-driven oscillation can arise; we will touch on the many alternatives for its elimination that were considered and investigated; and we will discuss three practical alternatives for eliminating combustion-driven oscillations.

  18. Hydrothermal processing of radioactive combustible waste

    Energy Technology Data Exchange (ETDEWEB)

    Worl, L.A.; Buelow, S.J.; Harradine, D.; Le, L.; Padilla, D.D.; Roberts, J.H.

    1998-09-01

    Hydrothermal processing has been demonstrated for the treatment of radioactive combustible materials for the US Department of Energy. A hydrothermal processing system was designed, built and tested for operation in a plutonium glovebox. Presented here are results from the study of the hydrothermal oxidation of plutonium and americium contaminated organic wastes. Experiments show the destruction of the organic component to CO{sub 2} and H{sub 2}O, with 30 wt.% H{sub 2}O{sub 2} as an oxidant, at 540 C and 46.2 MPa. The majority of the actinide component forms insoluble products that are easily separated by filtration. A titanium liner in the reactor and heat exchanger provide corrosion resistance for the oxidation of chlorinated organics. The treatment of solid material is accomplished by particle size reduction and the addition of a viscosity enhancing agent to generate a homogeneous pumpable mixture.

  19. Nonlinear Dynamic Characteristics of Combustion Wave in SHS Process

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The characteristic of combustion wave and its change were analyzed by numerical value calculation and computer simulation,based on the combustion dynamical model of SHS process. It is shown that with the change of condition parameters in SHS process various time-space order combustion waves appear.It is concluded from non-liner dynamical mechanism analysis that the strong coupling of two non-linear dynamical processes is the dynamical mechanism causing the time-space order dissipation structures.

  20. Simulating the in situ condensation process of solar prominences

    CERN Document Server

    Xia, Chun; Antolin, Patrick; Porth, Oliver

    2014-01-01

    Prominences in the solar corona are hundredfold cooler and denser than their surroundings, with a total mass of 1.e13 up to 1.e15 g. Here we report on the first comprehensive simulations of three-dimensional, thermally and gravitationally stratified magnetic flux ropes, where in situ condensation to a prominence happens due to radiative losses. After a gradual thermodynamic adjustment, we witness a phase where runaway cooling happens while counter-streaming shearing flows drain off mass along helical field lines. After this drainage, a prominence-like condensation resides in concave upward field regions, and this prominence retains its overall characteristics for more than two hours. While condensing, the prominence establishes a prominence-corona transition region, where magnetic field-aligned thermal conduction is operative during the runaway cooling. The prominence structure represents a force-balanced state in a helical flux rope. The simulated condensation demonstrates a right-bearing barb, as a remnant ...

  1. An evaluation of in-situ bioremediation processes

    Energy Technology Data Exchange (ETDEWEB)

    Cole, L.L. [Prairie View A and M Univ., TX (United States); Rashidi, M. [Lawrence Livermore National Lab., CA (United States). Environmental Programs Directorate

    1996-08-01

    Remediation of petroleum hydrocarbons in groundwater was the primary focus in the initial application of in-situ bioremediation which, from its development in the 1970s, has grown to become one of the most promising technologies for the degradation of a wide variety of organic contaminants. The degradation of contaminants in subsurface soils is the current new focus of the technology. While the need for improvements in the technology does exist, the indisputable fact remains that this technology is by far the least expensive and that it has the capability to provide long term reduced levels of contaminants or long term complete remediation of contaminated sites. The aim of this paper is to disclose pertinent information related to current conditions and current feelings in the area of new research, novel applications, new government regulations, and an overview of new topics on the horizon that relate to the overall technology.

  2. The adsorptive-kinetic model of in-situ phosphorus doped film polysilicon deposition process

    Directory of Open Access Journals (Sweden)

    Nalivaiko O. Yu.

    2009-11-01

    Full Text Available The investigation of deposition kinetics of in-situ phosphorus doped polysilicon films has been performed. The adsorptive-kinetic model of in-situ phosphorus doped polysilicon deposition has been developed. The values of heterogeneous reaction constants and constants, which describe the desorption process for monosilane and phosphine, have been defined. The optimal process conditions, which provide the acceptable deposition rate, thickness uniformity, high doping level and conformal step coverage, have been founded.

  3. SOLUTION OF THE PROBLEM OF OIL-POOL IN-SITU COMBUSTION FRONT PROPAGATION ON THE BASIS OF HEURISTIC HYPOTHESIS REGARDING TEMPERATURE AND CONCENTRATION PROFILES

    Directory of Open Access Journals (Sweden)

    K. V. Dobrego

    2016-01-01

    Full Text Available At present the number of oil deposits with viscous and stranded oil is steadily growing. Due to the mentioned circumstance there is growing interest in methods of thermochemical treatment of an oil and coal-beds. This interest is reflected, e.g., in the “Visha-Thermogaz” BelarusianRussian joint project. In order to provide control over the in-situ thermochemical processes it is necessary to use models of different levels, i.e. qualitative analysis, simplified numerical simulation with “averaged” parameters, as well as detailed 2D and 3D modeling. Due to variety of specific parameters and conditions of in-situ processes, design of new simplified methods of analysis is a topical objective both for research and practical activity. Therefore, a new method of solution of the problem of in-situ combustion front propagation based on heuristic hypothesis is discussed in the present article. The designed method is based on heuristic assumption of functional relationship between the profiles of temperature T and deficit component concentration y: exp(-E / T  = exp(-E / Tmax (1- y. Another hypothesis is the assumption that the maximum gradient of the concentration profile of the missing component is implemented with a fixed value of concentration that is expressed as y’’ ( y = y* = 0. Simple algebraic and differential equations fordetermination of the temperature and concentration profiles as well as for the front propagation velocity are derived for two cases i.e. the lack of oxidizer and the fuel component fault. Principal functional dependencies of the front velocity are revealed. Comparison of the profiles obtained with the use of the described method with the one obtained numerically proves the adequacy of the method itself and the hypotheses adopted. The method can be used for rapid assessment and parametric studies of the profiles and the speed of the front. It can also be used for analysis of similar problems

  4. SIMULATING THE IN SITU CONDENSATION PROCESS OF SOLAR PROMINENCES

    Energy Technology Data Exchange (ETDEWEB)

    Xia, C.; Keppens, R. [Centre for mathematical Plasma Astrophysics, Department of Mathematics, KU Leuven, Celestijnenlaan 200B, B-3001 Leuven (Belgium); Antolin, P. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Porth, O. [Department of Applied Mathematics, The University of Leeds, Leeds LS2 9JT (United Kingdom)

    2014-09-10

    Prominences in the solar corona are a hundredfold cooler and denser than their surroundings, with a total mass of 10{sup 13} up to 10{sup 15} g. Here, we report on the first comprehensive simulations of three-dimensional, thermally and gravitationally stratified magnetic flux ropes where in situ condensation to a prominence occurs due to radiative losses. After a gradual thermodynamic adjustment, we witness a phase where runaway cooling occurs while counter-streaming shearing flows drain off mass along helical field lines. After this drainage, a prominence-like condensation resides in concave upward field regions, and this prominence retains its overall characteristics for more than two hours. While condensing, the prominence establishes a prominence-corona transition region where magnetic field-aligned thermal conduction is operative during the runaway cooling. The prominence structure represents a force-balanced state in a helical flux rope. The simulated condensation demonstrates a right-bearing barb, as a remnant of the drainage. Synthetic images at extreme ultraviolet wavelengths follow the onset of the condensation, and confirm the appearance of horns and a three-part structure for the stable prominence state, as often seen in erupting prominences. This naturally explains recent Solar Dynamics Observatory views with the Atmospheric Imaging Assembly on prominences in coronal cavities demonstrating horns.

  5. Evaluating Acoustic Emission Signals as an in situ process monitoring technique for Selective Laser Melting (SLM)

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, Karl A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Candy, Jim V. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Guss, Gabe [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mathews, M. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-10-14

    In situ real-time monitoring of the Selective Laser Melting (SLM) process has significant implications for the AM community. The ability to adjust the SLM process parameters during a build (in real-time) can save time, money and eliminate expensive material waste. Having a feedback loop in the process would allow the system to potentially ‘fix’ problem regions before a next powder layer is added. In this study we have investigated acoustic emission (AE) phenomena generated during the SLM process, and evaluated the results in terms of a single process parameter, of an in situ process monitoring technique.

  6. Kinematic analysis of in situ measurement during chemical mechanical planarization process

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hongkai; Wang, Tongqing; Zhao, Qian; Meng, Yonggang; Lu, Xinchun, E-mail: xclu@tsinghua.edu.cn [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China)

    2015-10-15

    Chemical mechanical planarization (CMP) is the most widely used planarization technique in semiconductor manufacturing presently. With the aid of in situ measurement technology, CMP tools can achieve good performance and stable productivity. However, the in situ measurement has remained unexplored from a kinematic standpoint. The available related resources for the kinematic analysis are very limited due to the complexity and technical secret. In this paper, a comprehensive kinematic analysis of in situ measurement is provided, including the analysis model, the measurement trajectory, and the measurement time of each zone of wafer surface during the practical CMP process. In addition, a lot of numerical calculations are performed to study the influences of main parameters on the measurement trajectory and the measurement velocity variation of the probe during the measurement process. All the efforts are expected to improve the in situ measurement system and promote the advancement in CMP control system.

  7. Kinematic analysis of in situ measurement during chemical mechanical planarization process.

    Science.gov (United States)

    Li, Hongkai; Wang, Tongqing; Zhao, Qian; Meng, Yonggang; Lu, Xinchun

    2015-10-01

    Chemical mechanical planarization (CMP) is the most widely used planarization technique in semiconductor manufacturing presently. With the aid of in situ measurement technology, CMP tools can achieve good performance and stable productivity. However, the in situ measurement has remained unexplored from a kinematic standpoint. The available related resources for the kinematic analysis are very limited due to the complexity and technical secret. In this paper, a comprehensive kinematic analysis of in situ measurement is provided, including the analysis model, the measurement trajectory, and the measurement time of each zone of wafer surface during the practical CMP process. In addition, a lot of numerical calculations are performed to study the influences of main parameters on the measurement trajectory and the measurement velocity variation of the probe during the measurement process. All the efforts are expected to improve the in situ measurement system and promote the advancement in CMP control system.

  8. Signal Processing Methods for Liquid Rocket Engine Combustion Spontaneous Stability and Rough Combustion Assessments

    Science.gov (United States)

    Kenny, R. Jeremy; Casiano, Matthew; Fischbach, Sean; Hulka, James R.

    2012-01-01

    Liquid rocket engine combustion stability assessments are traditionally broken into three categories: dynamic stability, spontaneous stability, and rough combustion. This work focuses on comparing the spontaneous stability and rough combustion assessments for several liquid engine programs. The techniques used are those developed at Marshall Space Flight Center (MSFC) for the J-2X Workhorse Gas Generator program. Stability assessment data from the Integrated Powerhead Demonstrator (IPD), FASTRAC, and Common Extensible Cryogenic Engine (CECE) programs are compared against previously processed J-2X Gas Generator data. Prior metrics for spontaneous stability assessments are updated based on the compilation of all data sets.

  9. Signal Processing Methods for Liquid Rocket Engine Combustion Spontaneous Stability and Rough Combustion Assessments

    Science.gov (United States)

    Kenny, R. Jeremy; Casiano, Matthew; Fischbach, Sean; Hulka, James R.

    2012-01-01

    Liquid rocket engine combustion stability assessments are traditionally broken into three categories: dynamic stability, spontaneous stability, and rough combustion. This work focuses on comparing the spontaneous stability and rough combustion assessments for several liquid engine programs. The techniques used are those developed at Marshall Space Flight Center (MSFC) for the J-2X Workhorse Gas Generator program. Stability assessment data from the Integrated Powerhead Demonstrator (IPD), FASTRAC, and Common Extensible Cryogenic Engine (CECE) programs are compared against previously processed J-2X Gas Generator data. Prior metrics for spontaneous stability assessments are updated based on the compilation of all data sets.

  10. Analysis of in situ Reaction and Pressureless Infiltration Process in Fabricating TiC/Mg Composites

    Institute of Scientific and Technical Information of China (English)

    Qun DONG; Liqing CHEN; Mingjiu ZHAO; Jing BI

    2004-01-01

    An innovative processing route, in situ reaction combined with pressureless infiltration, was adopted to fabricate magnesium matrix composites, where the reinforcement TiC formed in situ from elemental Ti and C powders and molten Mg spontaneously infiltrated the preform of Ti and C. The influences of primarily elemental particle sizes,synthesizing temperature, holding time etc on in situ reactive infiltration for Mg-Ti-C system were systematically investigated in order to explore the mechanism of this process. In fabricating TiC/Mg composites, Mg can not only spontaneously infiltrate the preform of reinforcement and thus densify the as fabricated composites as matrix metal, but also it can accelerate the in situ reaction process and lower the synthesizing temperature of Ti and C as well. In situ reaction of Ti and C and Mg infiltration processes are essentially overlapping and interacting during fabrication of TiC/Mg composites. The mechanism proposed in this paper can be used to explain the formation and morphologies of the reinforcement phase TiC.

  11. Evaluation of Select Surface Processing Techniques for In Situ Application During the Additive Manufacturing Build Process

    Science.gov (United States)

    Book, Todd A.; Sangid, Michael D.

    2016-07-01

    Although additive manufacturing offers numerous performance advantages for different applications, it is not being used for critical applications due to uncertainties in structural integrity as a result of innate process variability and defects. To minimize uncertainty, the current approach relies on the concurrent utilization of process monitoring, post-processing, and non-destructive inspection in addition to an extensive material qualification process. This paper examines an alternative approach by evaluating the application of select surface process techniques, to include sliding severe plastic deformation (SPD) and fine particle shot peening, on direct metal laser sintering-produced AlSi10Mg materials. Each surface processing technique is compared to baseline as-built and post-processed samples as a proof of concept for surface enhancement. Initial results pairing sliding SPD with the manufacture's recommended thermal stress relief cycle demonstrated uniform recrystallization of the microstructure, resulting in a more homogeneous distribution of strain among the microstructure than as-built or post-processed conditions. This result demonstrates the potential for the in situ application of various surface processing techniques during the layerwise direct metal laser sintering build process.

  12. The research and development of in situ non intrusive optical and temperature diagnostics in an internal combustion engine

    CERN Document Server

    Wilson, T S

    2002-01-01

    Novel instrumentation has been developed and evaluated in a low-cost, purpose built, single-cylinder internal combustion engine test facility designed to simulate many of the combustion features that are common between an internal combustion engine, a gas turbine combustor and a steel rolling furnace. High bandwidth in-cylinder surface temperature measurements are demonstrated with a new application of platinum thin film resistance thermometers. These gauges are exposed to the combustion gases and are mounted to both the cylinder head and piston. It is shown that calculation of flame speed, determination of heat flux levels and flame structure observation are possible. Fibre optic probes capable of high frequency spectral measurements of the combustion emission are presented. The spectral measurements are shown to complement the temperature measurement by being able to differentiate the flame front from the general combustion emission and hot by-products. Beyond this, other optical techniques have been explor...

  13. Biodegradation Rates Assessment For An In Situ Bioremediation Process

    Science.gov (United States)

    Troquet, J.; Poutier, F.

    Bioremediation methods seem a promising way of dealing with soil and subsoil con- tamination by organic substances. The biodegradation process is supported by micro- organisms which use the organic carbon from the pollutants as energy source and cells building blocks. However, bioremediation is not yet universally understood and its success is still an intensively debated issue because all soils and groundwater are not able to sustain biological growth and, then, cannot be successfully bioremediated. The outcome of each degradation process depends on several factors, which, such as oxygen transfer and pollutant bio-availability, can be controlled and are therefore key variables of such bioremediation processes. Then, it is essential to carry out a fea- sibility study based on pilot-testing before starting a remediation project in order to determine the best formulation of nutrients and bacteria to use for the specific condi- tions encountered. The scope of this work is to study the main parameters of the process and its physi- cal limiting steps in order to determine the biodegradation rates in a specific case of contamination. Several ground samples from an actual petroleum hydrocarbon con- taminated site have been laboratory tested. Five fixed bed column reactors, enabling the study of the influence of the different op- erating variables on the biodegradation kinetics, are used. The stoichiometric equation for bacteria growth and pollutant degradation has been established, allowing the de- termination of mass balances. Biodegradation monitoring is achieved by continuously measuring the emissions of carbon dioxide production and intermittently by analysing residual hydrocarbons. Results lead to the knowledge of biodegradation rates which allow to determine the treatment duration and cost.

  14. EPA SITE DEMONSTRATION OF THE INTERNATIONAL WASTE TECHNOLOGIES/GEO-CON IN SITU STABILIZATION/ SOLIDIFICATION PROCESS

    Science.gov (United States)

    This paper presents an EPA evaluation of the first field demonstration of an in situ stabilization/solidification process for contaminated soil under the EPA Superfund Innovative Technology Evaluation (SITE) program. Demonstration of this process was a joint effort of two vendors...

  15. Process defects and in situ monitoring methods in metal powder bed fusion: a review

    Science.gov (United States)

    Grasso, Marco; Colosimo, Bianca Maria

    2017-04-01

    Despite continuous technological enhancements of metal Additive Manufacturing (AM) systems, the lack of process repeatability and stability still represents a barrier for the industrial breakthrough. The most relevant metal AM applications currently involve industrial sectors (e.g. aerospace and bio-medical) where defects avoidance is fundamental. Because of this, there is the need to develop novel in situ monitoring tools able to keep under control the stability of the process on a layer-by-layer basis, and to detect the onset of defects as soon as possible. On the one hand, AM systems must be equipped with in situ sensing devices able to measure relevant quantities during the process, a.k.a. process signatures. On the other hand, in-process data analytics and statistical monitoring techniques are required to detect and localize the defects in an automated way. This paper reviews the literature and the commercial tools for in situ monitoring of powder bed fusion (PBF) processes. It explores the different categories of defects and their main causes, the most relevant process signatures and the in situ sensing approaches proposed so far. Particular attention is devoted to the development of automated defect detection rules and the study of process control strategies, which represent two critical fields for the development of future smart PBF systems.

  16. Electrosleeve process for in-situ nuclear steam generator repair

    Energy Technology Data Exchange (ETDEWEB)

    Barton, R.A. [Ontario Hydro Technologies, Toronto, ON (Canada); Moran, T.E. [Framatome Technologies Inc., Lynchburg, VA (United States); Renaud, E. [Babcock and Wilcox Industries Ltd., Cambridge, ON (Canada)

    1997-07-01

    Degradation of steam generator (SG) tubing by localized corrosion is a widespread problem in the nuclear industry that can lead to costly forced out-ages, unit de-rating, SG replacement or even the permanent shutdown of a reactor. In response to the onset of SG tubing degradation at Ontario Hydro's Pickering Nuclear Generating Station (PNGS) Unit 5, and the determined unsuitability of conventional repair methods (mechanically expanded or welded sleeves) for Alloy 400, an alternative repair technology was developed. Electrosleeve is a non-intrusive, low-temperature process that involves the electrodeposition of a nanocrystalline nickel microalloy forming a continuously bonded, structural layer over the internal diameter of the degraded region. This technology is designed to provide a long-term pressure boundary repair, fully restoring the structural integrity of the damaged region to its original state. This paper describes the Electrosleeve process for SG tubing repair and the unique properties of the advanced sleeve material. The successful installation of Electrosleeves that have been in service for more than three years in Alloy 400 SG tubing at the Pickering-5 CANDU unit, the more recent extension of the technology to Alloy 600 and its demonstration in a U.S. pressurized water reactor (PWR), is presented. A number of PWR operators have requested plant operating technical specification changes to permit Electrosleeve SG tube repair. Licensing of the Electrosleeve by the U.S. Nuclear Regulatory Commission (NRC) is expected imminently. (author)

  17. In-situ characterization of colloidal soft solution processes.

    Energy Technology Data Exchange (ETDEWEB)

    Tallant, David Robert; Rodriguez, Mark Andrew; Bell, Nelson Simmons

    2003-11-01

    The purpose of this program was to investigate methods to characterize the colloidal stability of nanoparticles during the synthesis reaction, and to characterize their organization related to interparticle forces. Studies were attempted using Raman spectroscopy and ultrasonic attenuation to observe the nucleation and growth process with characterization of stability parameters such as the zeta potential. The application of the techniques available showed that the instrumentation requires high sensitivity to the concentration of the system. Optical routes can be complicated by the scattering effects of colloidal suspensions, but dilution can cause a lowering of signal that prevents collection of data. Acoustic methods require a significant particle concentration, preventing the observation of nucleation events. Studies on the dispersion of nanoparticles show that electrostatic routes are unsuccessful with molecular surfactants at high particle concentration due to electrostatic interaction collapse by counterions. The study of molecular surfactants show that steric lengths on the order of 2 nm are successful for dispersion of nanoparticle systems at high particle concentration, similar to dispersion with commercial polyelectrolyte surfactants.

  18. Heat production in depth up to 2500m via in situ combustion of methane using a counter-current heat-exchange reactor

    Science.gov (United States)

    Schicks, Judith Maria; Spangenberg, Erik; Giese, Ronny; Heeschen, Katja; Priegnitz, Mike; Luzi-Helbing, Manja; Thaler, Jan; Abendroth, Sven; Klump, Jens

    2014-05-01

    In situ combustion is a well-known method used for exploitation of unconventional oil deposits such as heavy oil/bitumen reservoirs where the required heat is produced directly within the oil reservoir by combustion of a small percentage of the oil. A new application of in situ combustion for the production of methane from hydrate-bearing sediments was tested at pilot plant scale within the first phase of the German national gas hydrate project SUGAR. The applied method of in situ combustion was a flameless, catalytic oxidation of CH4 in a counter-current heat-exchange reactor with no direct contact between the catalytic reaction zone and the reservoir. The catalyst permitted a flameless combustion of CH4 with air to CO2 and H2O below the auto-ignition temperature of CH4 in air (868 K) and outside the flammability limits. This led to a double secured application of the reactor. The relatively low reaction temperature allowed the use of cost-effective standard materials for the reactor and prevented NOx formation. Preliminary results were promising and showed that only 15% of the produced CH4 was needed to be catalytically burned to provide enough heat to dissociate the hydrates in the environment and release CH4. The location of the heat source right within the hydrate-bearing sediment is a major advantage for the gas production from natural gas hydrates as the heat is generated where it is needed without loss of energy due to transportation. As part of the second period of the SUGAR project the reactor prototype of the first project phase was developed further to a borehole tool. The dimensions of this counter-current heat-exchange reactor are about 540 cm in length and 9 cm in diameter. It is designed for applications up to depths of 2500 m. A functionality test and a pressure test of the reactor were successfully carried out in October 2013 at the continental deep drilling site (KTB) in Windischeschenbach, Germany, in 600 m depth and 2000 m depth, respectively

  19. Theoretic computing model of combustion process of asphalt smoke

    Institute of Scientific and Technical Information of China (English)

    HUANG Rui; CHAI Li-yuan; HE De-wen; PENG Bing; WANG Yun-yan

    2005-01-01

    Based on the data and methods provided by research literature, dispersing mathematical model of combustion process of asphalt smoke is set by theoretic analysis. Through computer programming, the dynamic combustion process of asphalt smoke is calculated to simulate an experimental model. The computing result shows that the temperature and the concentration of asphalt smoke influence its burning temperature in approximatively linear manner. The consumed quantity of fuel to ignite the asphalt smoke needs to be measured from the two factors.

  20. Oxygen isotopic signature of CO2 from combustion processes

    Directory of Open Access Journals (Sweden)

    W. A. Brand

    2011-02-01

    Full Text Available For a comprehensive understanding of the global carbon cycle precise knowledge of all processes is necessary. Stable isotope (13C and 18O abundances provide information for the qualification and the quantification of the diverse source and sink processes. This study focuses on the δ18O signature of CO2 from combustion processes, which are widely present both naturally (wild fires, and human induced (fossil fuel combustion, biomass burning in the carbon cycle. All these combustion processes use atmospheric oxygen, of which the isotopic signature is assumed to be constant with time throughout the whole atmosphere. The combustion is generally presumed to take place at high temperatures, thus minimizing isotopic fractionation. Therefore it is generally supposed that the 18O signature of the produced CO2 is equal to that of the atmospheric oxygen. This study, however, reveals that the situation is much more complicated and that important fractionation effects do occur. From laboratory studies fractionation effects on the order of up to 26%permil; became obvious in the derived CO2 from combustion of different kinds of material, a clear differentiation of about 7‰ was also found in car exhausts which were sampled directly under ambient atmospheric conditions. We investigated a wide range of materials (both different raw materials and similar materials with different inherent 18O signature, sample geometries (e.g. texture and surface-volume ratios and combustion circumstances. We found that the main factor influencing the specific isotopic signatures of the combustion-derived CO2 and of the concomitantly released oxygen-containing side products, is the case-specific rate of combustion. This points firmly into the direction of (diffusive transport of oxygen to the reaction zone as the cause of the isotope fractionation. The original total 18O signature of the material appeared to have little influence, however, a contribution of specific bio

  1. In situ heat treatment process utilizing a closed loop heating system

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J. (Bellaire, TX); Nguyen, Scott Vinh (Houston, TX)

    2010-12-07

    Systems and methods for an in situ heat treatment process that utilizes a circulation system to heat one or more treatment areas are described herein. The circulation system may use a heated liquid heat transfer fluid that passes through piping in the formation to transfer heat to the formation. In some embodiments, the piping may be positioned in at least two of the wellbores.

  2. Challenges in simulation of chemical processes in combustion furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Hupa, M.; Kilpinen, P. [Aabo Akademi, Turku (Finland)

    1996-12-31

    The presentation gives an introduction to some of the present issues and problems in treating the complex chemical processes in combustion. The focus is in the coupling of the hydrocarbon combustion process with nitrogen oxide formation and destruction chemistry in practical furnaces or flames. Detailed kinetic modelling based on schemes of elementary reactions are shown to be a useful novel tool for identifying and studying the key reaction paths for nitrogen oxide formation and destruction in various systems. The great importance of the interaction between turbulent mixing and combustion chemistry is demonstrated by the sensitivity of both methane oxidation chemistry and fuel nitrogen conversion chemistry to the reactor and mixing pattern chosen for the kinetic calculations. The fluidized bed combustion (FBC) nitrogen chemistry involves several important heterogeneous reactions. Particularly the char in the bed plays an essential role. Recent research has advanced rapidly and the presentation proposes an overall picture of the fuel nitrogen reaction routes in circulating FBC conditions. (author)

  3. Determination of intermediates and mechanism for soot combustion with NOx/O₂ on potassium-supported Mg-Al hydrotalcite mixed oxides by in situ FTIR.

    Science.gov (United States)

    Zhang, Zhaoliang; Zhang, Yexin; Su, Qingyun; Wang, Zhongpeng; Li, Qian; Gao, Xiyan

    2010-11-01

    The soot combustion with NO(x) and/or O(2) on potassium-supported Mg-Al hydrotalcite mixed oxides under tight contact condition was studied using temperature-programmed oxidation (TPO), isothermal reaction and in situ FTIR techniques. The presence of NO(x) in O(2) favors the soot combustion at lower temperatures (300 °C), which was accompanied by a substantial NO(x) reduction. The ketene (C═C═O) and isocyanate (NCO(-)) species were determined as the reaction intermediates. In NO(x) + O(2), NO(2) directly interacts with the free carbon sites (C═C*) through two parallel reactions: (1) NO(2) + C═C* → C═C═O + NO; (2) NO(2) + C═C* → NCO(-) + CO(2). The two reactions can proceed easily, which accounts for the promotion effect of NO(x) on soot combustion at lower temperatures. The further oxidation of NCO(-) by NO(2) or O(2) is responsible for the simultaneous reduction of NO(x). However, the reactions between NO(2) and C═C* are limited by the amount of free carbon sites, which can be provided by the oxidation of soot by O(2) at higher temperatures. The interaction of NO(x) and catalyst results in the formation of nitrates and nitrites, which poisoned the active K sites.

  4. Combustion

    CERN Document Server

    Glassman, Irvin

    1987-01-01

    Combustion, Second Edition focuses on the underlying principles of combustion and covers topics ranging from chemical thermodynamics and flame temperatures to chemical kinetics, detonation, ignition, and oxidation characteristics of fuels. Diffusion flames, flame phenomena in premixed combustible gases, and combustion of nonvolatile fuels are also discussed. This book consists of nine chapters and begins by introducing the reader to heats of reaction and formation, free energy and the equilibrium constants, and flame temperature calculations. The next chapter explores the rates of reactio

  5. Monitoring the evolution of crystallization processes by in-situ solid-state NMR spectroscopy.

    Science.gov (United States)

    Harris, Kenneth D M; Hughes, Colan E; Williams, P Andrew

    2015-02-01

    Crystallization processes play a crucial role in many aspects of biological and physical sciences. Progress in deepening our fundamental understanding of such processes relies, to a large extent, on the development and application of new experimental strategies that allow direct in-situ monitoring of the process. In this paper, we give an overview of an in-situ solid-state NMR strategy that we have developed in recent years for monitoring the time-evolution of different polymorphic forms (or other solid forms) that arise as the function of time during crystallization from solution. The background to the strategy is described and several examples of the application of the technique are highlighted, focusing on both the evolution of different polymorphs during crystallization and the discovery of new polymorphs.

  6. In situ characterization of the nitridation of dysprosium during mechanochemical processing

    Energy Technology Data Exchange (ETDEWEB)

    Jaques, Brian J.; Osterberg, Daniel D.; Alanko, Gordon A.; Tamrakar, Sumit; Smith, Cole R.; Hurley, Michael F.; Butt, Darryl P., E-mail: DarrylButt@BoiseState.edu

    2015-01-15

    Highlights: • A nitridation reaction in a high energy planetary ball mill was monitored in situ. • Dysprosium mononitride was synthesized from Dy at low temperatures in short times. • Ideal gas law and in situ temperature and pressure used to assess reaction extent. • It is proposed that reaction rate is proportional to the creation of new surface. - Abstract: Processing of advanced nitride ceramics traditionally requires long durations at high temperatures and, in some cases, in hazardous atmospheres. In this study, dysprosium mononitride (DyN) was rapidly formed from elemental dysprosium in a closed system at ambient temperatures. An experimental procedure was developed to quantify the progress of the nitridation reaction during mechanochemical processing in a high energy planetary ball mill (HEBM) as a function of milling time and intensity using in situ temperature and pressure measurements, SEM, XRD, and particle size analysis. No intermediate phases were formed. It was found that the creation of fresh dysprosium surfaces dictates the rate of the nitridation reaction, which is a function of milling intensity and the number of milling media. These results show clearly that high purity nitrides can be synthesized with short processing times at low temperatures in a closed system requiring a relatively small processing footprint.

  7. Sulfur Chemistry in Combustion I

    DEFF Research Database (Denmark)

    Johnsson, Jan Erik; Glarborg, Peter

    2000-01-01

    of the sulphur compounds in fossil fuels and the possibilities to remove them will be given. Then the combustion of sulphur species and their influence on the combustion chemistry and especially on the CO oxidation and the NOx formation will be described. Finally the in-situ removal of sulphur in the combustion...... process by reaction between SO2 and calcium containing sorbents and the influence on the NOx chemistry will be treated....

  8. In-situ real time monitoring of the polymerization in gel-cast ceramic processes

    Energy Technology Data Exchange (ETDEWEB)

    Ahuja, S.; Dieckman, S.L.; Bostrom, G.A.; Waterfield, L.G.; Raptis, A.C. [Argonne National Lab., IL (United States); Omatete, O.O. [Oak Ridge National Lab., TN (United States)

    1996-08-01

    Gelcasting requires making a mixture of a slurry of ceramic powder in a solution of organic monomers and casting it in a mold. Gelcasting is different from injection molding in that it separates mold filling from setting during conversion of the ceramic slurry to a formed green part. In this work, NMR spectroscopy and imaging were used for in-situ monitoring of the gelation process and gelcasting of alumina. {sup 1}H NMR spectra and images are obtained during polymerization of a mixture of soluble reactive acrylamide monomers. Polymerization was initiated by adding an initiator and an accelerator to form long- chain, crosslinked polymers. Multidimensional NMR imaging was used for in-situ monitoring of the process and for verification of homogeneous polymerization. Comparison of the modeled intensities with acquired images shows a direction extraction of T{sub 1} data from the images.

  9. Synthesis of copper-niobium carbide composite powder by in situ processing

    Energy Technology Data Exchange (ETDEWEB)

    Hussain, Zuhailawati [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia)], E-mail: zuhaila@eng.usm.my; Othman, Radzali; Long, Bui Duc [School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia); Umemoto, Minoru [Department of Production Systems Engineering, Toyohashi University of Technology (Japan)

    2008-09-22

    The in situ formation of niobium carbide (NbC) particles was investigated during mechanical alloying process as well as subsequent heat-treatment. Initial starting powders of Cu, Nb and C were used with a composition of Cu-40 wt% Nb-10 wt% C which was corresponding to Cu-40 vol% NbC. A mixture of this powder system was milled in an argon atmosphere for four different durations, i.e., 15 h, 31 h, 42 h and 54 h. X-ray diffraction was used to verify the formation of NbC. No NbC was formed after the milling process. The in situ formation of NbC in a copper matrix only took place after heat-treatment at 900 deg. C. Longer milling time resulted in the formation of NbC phase with more intense X-ray diffraction peaks due to powder refinement.

  10. Optimization of process parameters for friction stir processing (FSP) of Al–TiC in situ composite

    Indian Academy of Sciences (India)

    Ranjit Bauri

    2014-05-01

    Segregation of in situ formed particles at the grain boundaries is a major drawback of in situ composites. In this study, it has been demonstrated that friction stir processing (FSP) can be used as an effective tool to homogenize the particle distribution in Al based in situ composites and FSP processing parameters were optimized for this purpose. An Al-5 wt% TiC composite was processed in situ using K2TiF6 and graphite in Al melt and subjected to FSP. Processing parameters for FSP were optimized to get a defect free stir zone and homogenize the particle distribution. It was found that a rotation speed > 800 rpm is needed. A rotation speed of 1000 rpm and a traverse speed of 60 mm/min were found to be an optimum combination. The grain size was also refined in addition to homogenization of the as-cast microstructure. This resulted in significant improvement in the mechanical properties of the processed composite.

  11. From Alloy Processing to Performance: An In Situ Experimental and Modeling Effort

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, Amy Jean [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tourret, Damien [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gibbs, John W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Imhoff, Seth D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lebensohn, Ricardo A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Patterson, Brian M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mertens, James CE. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Henderson, Kevin C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-04-15

    Solidification is present in almost all materials. It is influenced by grain size and shape, chemical homogeneity, defect type and density, and mechanical properties. During micro-mechanical testing, the following occur: 1) Micro-CT (as processed) - Map Initial 3D Microstructure 2) Nano-Radiography (In situ under Tension) - Observe of Damage Initiation/Propagation 3) Micro-CT (Post Mortem) - Global Fracture Study 4) Nano-CT (Post Mortem) - High-Resolution Fracture Study.

  12. Digital processing of in situ hybridization images: identification and spatial allocation of specific labels

    OpenAIRE

    2007-01-01

    In situ hybridization (ISH) method allows to reveal specific genes expression, identify specific cell types and detect areas or tissues, displaying differential gene expression. This work describes a standardized procedure of digital image processing that allows detailed analyses of ISH preparations. We have developed a software that allows through a graphical interface (a) to reliably identify and quantify ISH labels, (b) to locate each label within the image reference system (c) to assemble...

  13. Ultrafast laser processing of transparent materials supported by in-situ diagnostics

    Science.gov (United States)

    Kumkar, M.; Kaiser, M.; Kleiner, J.; Grossmann, D.; Flamm, D.; Bergner, K.; Nolte, S.

    2016-03-01

    For the development of industrial NIR ultrafast laser processing of transparent materials, the absorption inside the bulk material has to be controlled. Applications we aim for are front and rear side ablation, drilling and inscription of modifications for cleaving and selective laser etching of glass and sapphire in sheet geometry. We applied pump probe technology and in situ stress birefringence microscopy for fundamental studies on the influence of energy and duration (100 fs - 20 ps), temporal and spatial spacing, focusing and beam shaping of the laser pulses. Applying pump probe technique we are able to visualize differences of spatio-temporal build up of absorption, self focusing, shock wave generation for standard, multispot and beam shaped focusing. Incubation effects and disturbance of beam propagation due to modifications or ablation can be observed. In-situ imaging of stress birefringence gained insight in transient build up of stress with and without translation. The results achieved so far, demonstrate that transient stress has to be taken into account in scaling the laser machining throughput of brittle materials. Furthermore it points out that transient stress birefringence is a good indicator for accumulation effects, supporting tailored processing strategies. Cutting results achieved for selective laser etching by single pass laser modification exemplifies the benefits of process development supported by in situ diagnostics.

  14. COMPUTATIONALLY INTELLIGENT MODELLING AND CONTROL OF FLUIDIZED BED COMBUSTION PROCESS

    Directory of Open Access Journals (Sweden)

    Ivan T Ćirić

    2011-01-01

    Full Text Available In this paper modelling and control approaches for fluidized bed combustion process have been considered, that are based on the use of computational intelligence. Proposed adaptive neuro-fuzzy-genetic modelling and intelligent control strategies provide for efficient combining of available expert knowledge with experimental data. Firstly, based on the qualitative information on the desulphurization process, models of the SO2 emission in fluidized bed combustion have been developed, which provides for economical and efficient reduction of SO2 in FBC by estimation of optimal process parameters and by design of intelligent control systems based on defined emission models. Also, efficient fuzzy nonlinear FBC process modelling strategy by combining several linearized combustion models has been presented. Finally, fuzzy and conventional process control systems for fuel flow and primary air flow regulation based on developed models and optimized by genetic algorithms have also been developed. Obtained results indicate that computationally intelligent approach can be successfully applied for modelling and control of complex fluidized bed combustion process.

  15. In-situ laser material process monitoring using a cladding power detection technique

    Science.gov (United States)

    Su, Daoning; Norris, Ian; Peters, Chris; Hall, Denis R.; Jones, Julian D. C.

    Progress in laser material processing may require real-time monitoring and process control for consistent quality and productivity. We report a method of in-situ monitoring of laser metal cutting and drilling using cladding power monitoring of an optical fibre beam delivery system—a technique which detects the light reflected or scattered from the workpiece. The light signal carries information about the quality of the process. Experiments involving drilling and cutting of two samples, a thin aluminum foil and a 2-mm thick stainless steel plate, confirmed the effectiveness of this method.

  16. Combustion Joining of Regolith Tiles for In-Situ Fabrication of Launch/Landing Pads on the Moon and Mars

    Science.gov (United States)

    Ferguson, Robert E.; Shafirovich, Evgeny; Mantovani, James G.

    2017-01-01

    To mitigate dust problems during launch/landing operations in lunar and Mars missions, it is desired to build solid pads on the surface. Recently, strong tiles have been fabricated from lunar regolith simulants using high-temperature sintering. The present work investigates combustion joining of these tiles through the use of exothermic intermetallic reactions. Specifically, nickel/aluminum (1:1 mole ratio) mixture was placed in a gap between the tiles sintered from JSC-1A lunar regolith simulant. Upon ignition by a laser, a self-sustained propagation of the combustion front over the mixture occurred. Joining was improved with increasing the tile thickness from 6.3 mm to 12.7 mm. The temperatures sufficient for melting the glass phase of JSC-1A were recorded for 12.7-mm tiles, which explains the observed better joining.

  17. Study on the in-situ coupling process of fermentation, extraction and distillation for biobutanol production: process analysis

    Science.gov (United States)

    Jin, Fuqiang; Zhang, Xiaodong; Hua, Dongliang; Xu, Haipeng; Li, Yan; Mu, Hui

    2017-01-01

    The transfer process of the in-situ coupling process of fermentation, extraction and distillation for biobutanol production was discussed from a theoretical point of view. The existence of temperature gradient in the extraction section was proved. The force of solute in the extracted liquid was discussed. And the mass transfer mechanism and impetus of the FEDIC process was analyzed. The theoretical analysis could provide a foundation for the following research.

  18. A quantitative framework for understanding complex interactions between competing interfacial processes and in situ biodegradation

    Science.gov (United States)

    Johnson, Mark A.; Song, Xin; Seagren, Eric A.

    2013-03-01

    In situ bioremediation of contaminated groundwater is made technologically challenging by the physically, chemically, and biologically heterogeneous subsurface environment. Subsurface heterogeneities are important because of influences on interfacial mass transfer processes that impact the availability of substrates to microorganisms. The goal of this study was to perform a "proof-of-concept" evaluation of the utility of a quantitative framework based on a set of dimensionless coefficients for evaluating the effects of competing physicochemical interfacial and biokinetic processes at the field scale. First, three numerical modeling experiments were completed, demonstrating how the framework can be used to identify the rate-limiting process for the overall bioremediation rate, and to predict what engineered enhancements will alleviate the rate-limiting process. Baseline conditions for each scenario were established to examine intrinsic biodegradation with a given rate-limiting process (either dispersion, biokinetics, or sorption). Then different engineering treatments were examined. In each case, the treatment predicted to be appropriate for addressing the overall rate-limiting process based on the quantitative framework alleviated the limitation more successfully, and enhanced the in situ biodegradation rate more than the alternative enhancements. Second, the quantitative framework was applied to a series of large-scale laboratory and field-scale experiments, using reported parameter estimates to calculate the relevant dimensionless coefficients and predict the rate-limiting process(es). Observations from the studies were then used to evaluate those predictions.

  19. Modeling of large-scale oxy-fuel combustion processes

    DEFF Research Database (Denmark)

    Yin, Chungen

    2012-01-01

    , among which radiative heat transfer under oxy-fuel conditions is one of the fundamental issues. This paper demonstrates the nongray-gas effects in modeling of large-scale oxy-fuel combustion processes. Oxy-fuel combustion of natural gas in a 609MW utility boiler is numerically studied, in which....... The simulation results show that the gray and non-gray calculations of the same oxy-fuel WSGGM make distinctly different predictions in the wall radiative heat transfer, incident radiative flux, radiative source, gas temperature and species profiles. In relative to the non-gray implementation, the gray...

  20. In situ monitoring of biomolecular processes in living systems using surface-enhanced Raman scattering

    Science.gov (United States)

    Altunbek, Mine; Kelestemur, Seda; Culha, Mustafa

    2015-12-01

    Surface-enhanced Raman scattering (SERS) continues to strive to gather molecular level information from dynamic biological systems. It is our ongoing effort to utilize the technique for understanding of the biomolecular processes in living systems such as eukaryotic and prokaryotic cells. In this study, the technique is investigated to identify cell death mechanisms in 2D and 3D in vitro cell culture models, which is a very important process in tissue engineering and pharmaceutical applications. Second, in situ biofilm formation monitoring is investigated to understand how microorganisms respond to the environmental stimuli, which inferred information can be used to interfere with biofilm formation and fight against their pathogenic activity.

  1. InSitu-Eye: oceanological and atmospheric data processing and analyzing system

    Science.gov (United States)

    Stepochkin, Igor E.; Salyuk, Pavel A.; Shmirko, Konstantin A.; Golik, Irina A.; Burov, Denis V.

    2014-11-01

    In this study we introduce brief description and the main approaches used in system development. System is devising with a participation of Pacific Oceanological Institute (FEB RAS), Institute of Automation and Control Processes (FEB RAS) and also Maritime State University, n.a. G.I. Nevelskoy. For many years research team of these institutions carried out a lot of field measurements and collected a lot of remote sensing data, using spectrophotometers, LIDARs, fluorometers. The primary goal of this development - bring all this data together to integrated database and design user-friendly interface to work with. "InSitu-Eye" will perform standard routine operations, such as sampling data according to certain parameters; gridding and timing of data; filtering and quality check of data; visualization. After setting system up and testing it will provide a benefit. At first it gives 24/7 access to "clean", checked "in-situ" data, ready for further research. Also presence of such system gives "converse effect" - it will become necessary to develop strict protocols for measurements carrying out and increase their quality. In future, "InSitu-Eye" can become a platform, connecting research teams for data keeping and exchange.

  2. Numerical simulation of the coal combustion process initiated by a plasma source

    Science.gov (United States)

    Askarova, A. S.; Messerle, V. E.; Ustimenko, A. B.; Bolegenova, S. A.; Maksimov, V. Yu.

    2014-12-01

    Numerical experiments on the torch combustion of the coal dust prepared by a plasma-thermochemical treatment for combustion have been done using the method of three-dimensional simulation. It is shown that the plasma preparation of coal for combustion enables one to optimize the process, improve the conditions for inflammation and combustion and minimize the emissions of harmful substances.

  3. Effects of aqueous effluents from in situ fossil-fuel processing technologies on aquatic systems

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, H.L.

    1978-12-01

    Progress is reported for the second year of this project to evaluate the effects of aqueous effluents from in-situ fossil fuel processing technologies on aquatic biota. The project objectives for Year 2 were pursued through five tasks: literature reviews on process water constituents, possible environmental impacts and potential control technologies; toxicity bioassays on the effects of coal gasification and oil shale retorting process waters and six process water constituents on aquatic biota; biodegradation studies on process water constituents; bioaccumulation factor estimation for the compounds tested in the toxicity bioassays; and recommendations on maximum exposure concentrations for process water constituents based on data from the project and from the literature. Results in each of the five areas of research are reported.

  4. U-GAS coal gasification process with in-situ desulfurization

    Energy Technology Data Exchange (ETDEWEB)

    Rehmat, A.; Abbasian, J.; Lau, F.

    1990-01-01

    Calcium based sorbents such as limestone and dolomite have been used in conjunction with the U-GAS coal gasification process for in-situ capture of sulfur present in the coal. Under the reducing conditions of the gasifier, these sorbents react with sulfur compounds to form calcium sulfide. As a unique feature of the U-GAS process, the calcium sulfide could be further reacted with air in the ash discharge zone to form calcium sulfate, which is environmentally acceptable for disposal directly from the gasifier along with the agglomerated ash. The Institute of Gas Technology (IGT) has conducted considerable testing in this area under different programs. The suitability of dolomite as in-situ sulfur capturing agent has been verified in U-GAS process using high-sulfur Pittsburgh coal. The gasification tests were conducted at 1850{degree}F in pressure ranges of 100 to 450 psig. The kinetics of the reaction between calcium based sorbents and hydrogen sulfide at these gasification conditions have been derived separately using a thermogravimetric technique. Effect of temperature, pressure, and particle size on the reaction rate were also included in these latter tests. Furthermore, the operating conditions and the type of sorbents suitable for achieving maximum calcium conversion to calcium sulfate during the oxidation step of the process have also been identified. 9 refs., 8 figs., 10 tabs.

  5. Methods of producing alkylated hydrocarbons from an in situ heat treatment process liquid

    Science.gov (United States)

    Roes, Augustinus Wilhelmus Maria; Mo, Weijian; Muylle, Michel Serge Marie; Mandema, Remco Hugo; Nair, Vijay

    2009-09-01

    A method for producing alkylated hydrocarbons is disclosed. Formation fluid is produced from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes olefins. The liquid stream is fractionated to produce at least a second gas stream including hydrocarbons having a carbon number of at least 3. The first gas stream and the second gas stream are introduced into an alkylation unit to produce alkylated hydrocarbons. At least a portion of the olefins in the first gas stream enhance alkylation.

  6. In-situ Non-destructive Studies on Biofouling Processes in Reverse Osmosis Membrane Systems

    KAUST Repository

    Farhat, Nadia

    2016-12-01

    Reverse osmosis (RO) and nanofiltration (NF) membrane systems are high-pressure membrane filtration processes that can produce high quality drinking water. Biofouling, biofilm formation that exceeds a certain threshold, is a major problem in spiral wound RO and NF membrane systems resulting in a decline in membrane performance, produced water quality, and quantity. In practice, detection of biofouling is typically done indirectly through measurements of performance decline. Existing direct biofouling detection methods are mainly destructive, such as membrane autopsies, where biofilm samples can be contaminated, damaged and resulting in biofilm structural changes. The objective of this study was to test whether transparent luminescent planar oxygen sensing optodes, in combination with a simple imaging system, can be used for in-situ, non-destructive biofouling characterization. Aspects of the study were early detection of biofouling, biofilm spatial patterning in spacer filled channels, and the effect of feed cross-flow velocity, and feed flow temperature. Oxygen sensing optode imaging was found suitable for studying biofilm processes and gave detailed spatial and quantitative biofilm development information enabling better understanding of the biofouling development process. The outcome of this study attests the importance of in-situ, non-destructive imaging in acquiring detailed knowledge on biofilm development in membrane systems contributing to the development of effective biofouling control strategies.

  7. Productivity of chironomid larvae exposed to oil sands process water : in situ vs. lab bioassay results

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, K.; Ciborowski, J. [Windsor Univ., ON (Canada)

    2010-07-01

    Oil sands process water (OSPW) contains toxic concentrations of salts and napthenic acids that may compromise wetland reclamation efforts. The productivity of wetland biota is one of the criteria used by the Alberta government to determine if land leased to oil sands mining companies is restored. This study determined how chironomid productivity is influenced by the water from oil sands process material (OSPM) affected wetland. In this study, 26 10-day in situ and laboratory bioassays from water of three oil sands process material (OSPM) were compared with water from 3 reference wetlands to determine the influence of water from OSPM affected wetlands on chironomid productivity. Parallel studies were conducted with Chironomus riparius lab-cultured larvae and Chironomus sp larvae cultured from egg masses collected from an OSPW-affected wetland. In situ, chironomids were housed in small cylinders with fine-mesh netting to allow water exchange and contact with the sediment. Preliminary estimates of chironomids emerging from study wetlands indicated that native and lab cultured chironomids are not uniformly responsive to OSPW.

  8. Pulsed combustion process for black liquor gasification

    Energy Technology Data Exchange (ETDEWEB)

    Durai-Swamy, K.; Mansour, M.N.; Warren, D.W.

    1991-02-01

    The objective of this project is to test an energy efficient, innovative black liquor recovery system on an industrial scale. In the MTCI recovery process, black liquor is sprayed directly onto a bed of sodium carbonate solids which is fluidized by steam. Direct contact of the black liquor with hot bed solids promotes high rates of heating and pyrolysis. Residual carbon, which forms as a deposit on the particle surface, is then gasified by reaction with steam. Heat is supplied from pulse combustor resonance tubes which are immersed within the fluid bed. A portion of the gasifier product gas is returned to the pulse combustors to provide the energy requirements of the reactor. Oxidized sulfur species are partially reduced by reaction with the gasifier products, principally carbon monoxide and hydrogen. The reduced sulfur decomposed to solid sodium carbonate and gaseous hydrogen sulfide (H{sub 2}S). Sodium values are recovered by discharging a dry sodium carbonate product from the gasifier. MTCI's indirectly heated gasification technology for black liquor recovery also relies on the scrubbing of H{sub 2}S for product gases to regenerate green liquor for reuse in the mill circuit. Due to concerns relative to the efficiency of sulfur recovery in the MTCI integrated process, an experimental investigation was undertaken to establish performance and design data for this portion of the system.

  9. Literature survey of in situ processes for application to the US tar sand resource

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Jr., L. A.

    1989-08-01

    Tar sands in the United States and worldwide are a large potential source of hydrocarbon liquids that has yet to be sufficiently developed. The development of the US tar sand resource lags the worldwide development and poses a challenge that has not been eagerly accepted by the petroleum industry. This paper reviews the developmental status of in situ enhanced oil recovery techniques that have been proposed for the production of heavy oils or bitumen and determines which process or processes are in the forefront for application to the US resource. Also noted is what developmental work, if any, remains to be accomplished before field testing of the process(es). The review used only information available in the public domain. 196 refs., 1 fig., 2 tabs.

  10. Influence of thermomechanical processing on the structure and properties of Cu-Ag alloy in situ composites

    Institute of Scientific and Technical Information of China (English)

    NING; Yuan-tao; ZHANG; Xiao-hui; ZHANG; Jie

    2005-01-01

    The influences of the thermomechanical processing, including the solidification conditions, the cold deformation and the intermediate annealing treatment, on the structure and properties of the Cu-10Ag alloy in situ composite were studied in this paper. The cast structure and the structural changes in the cold deformation and intermediate annealing process were observed. The properties including the ultimate tensile strength (UTS) and the electrical conductivity were determined. A two-stage strain strengthening effect for the Cu-10Ag alloy in situ filamentary composite was observed. The factors influencing the UTS and conductivity were discussed. The solidification conditions in the range of 10-1000 K/s cooling rates and the intermediate heat treatment showed obviously influence on the structure and properties on the Cu-10Ag alloy in situ filamentary composite. The typical properties of the Cu-Ag alloy in situ filamentary composites through thermomechanical processing were reported.

  11. Discrete magic angle turning system, apparatus, and process for in situ magnetic resonance spectroscopy and imaging

    Science.gov (United States)

    Hu, Jian Zhi [Richland, WA; Sears, Jr., Jesse A.; Hoyt, David W [Richland, WA; Wind, Robert A [Kennewick, WA

    2009-05-19

    Described are a "Discrete Magic Angle Turning" (DMAT) system, devices, and processes that combine advantages of both magic angle turning (MAT) and magic angle hopping (MAH) suitable, e.g., for in situ magnetic resonance spectroscopy and/or imaging. In an exemplary system, device, and process, samples are rotated in a clockwise direction followed by an anticlockwise direction of exactly the same amount. Rotation proceeds through an angle that is typically greater than about 240 degrees but less than or equal to about 360 degrees at constant speed for a time applicable to the evolution dimension. Back and forth rotation can be synchronized and repeated with a special radio frequency (RF) pulse sequence to produce an isotropic-anisotropic shift 2D correlation spectrum. The design permits tubes to be inserted into the sample container without introducing plumbing interferences, further allowing control over such conditions as temperature, pressure, flow conditions, and feed compositions, thus permitting true in-situ investigations to be carried out.

  12. A combined process coupling phytoremediation and in situ flushing for removal of arsenic in contaminated soil.

    Science.gov (United States)

    Yan, Xiulan; Liu, Qiuxin; Wang, Jianyi; Liao, Xiaoyong

    2017-07-01

    Phytoremediation and soil washing are both potentially useful for remediating arsenic (As)-contaminated soils. We evaluated the effectiveness of a combined process coupling phytoremediation and in situ soil flushing for removal of As in contaminated soil through a pilot study. The results showed that growing Pteris vittata L. (P.v.) accompanied by soil flushing of phosphate (P.v./Flushing treatment) could significantly decrease the total As concentration of soil over a 37day flushing period compared with the single flushing (Flushing treatment). The P.v./Flushing treatment removed 54.04% of soil As from contaminated soil compared to 47.16% in Flushing treatment, suggesting that the growth of P. vittata was beneficial for promoting the removal efficiency. We analyzed the As fractionation in soil and As concentration in soil solution to reveal the mechanism behind this combined process. Results showed that comparing with the control treatment, the percent of labile arsenate fraction significantly increased by 17% under P.v./Flushing treatment. As concentration in soil solution remained a high lever during the middle and later periods (51.26-56.22mg/L), which was significantly higher than the Flushing treatment. Although soil flushing of phosphate for more than a month, P. vittata still had good accumulation and transfer capacity of As of the soil. The results of the research revealed that combination of phytoremediation and in situ soil flushing is available to remediate As-contaminated soils. Copyright © 2016. Published by Elsevier B.V.

  13. New in situ solid-state NMR strategies for exploring materials formation and adsorption processes: prospects in heterogenous catalysis

    OpenAIRE

    Harris, Kenneth David Maclean

    2016-01-01

    Solid-state NMR spectroscopy is a powerful technique for studying structural and dynamic properties of solids and has considerable potential to be exploited for in situ studies of chemical processes. However, adapting solid-state NMR techniques and instrumentation for in situ applications are often associated with technical challenges, and for this reason, the opportunities remain underexploited. This paper highlights two experimental strategies that we have developed in recent years for in s...

  14. Morphology Development in Solution-Processed Functional Organic Blend Films: An In Situ Viewpoint

    KAUST Repository

    Richter, Lee J.

    2017-04-17

    Solution-processed organic films are a facile route to high-speed, low cost, large-area deposition of electrically functional components (transistors, solar cells, emitters, etc.) that can enable a diversity of emerging technologies, from Industry 4.0, to the Internet of things, to point-of-use heath care and elder care. The extreme sensitivity of the functional performance of organic films to structure and the general nonequilibrium nature of solution drying result in extreme processing-performance correlations. In this Review, we highlight insights into the fundamentals of solution-based film deposition afforded by recent state-of-the-art in situ measurements of functional film drying. Emphasis is placed on multimodal studies that combine surface-sensitive X-ray scattering (GIWAXS or GISAXS) with optical characterization to clearly define the evolution of solute structure (aggregation, crystallinity, and morphology) with film thickness.

  15. In Situ Observation of Solidification Process of AISI 304 Austenitic Stainless Steel

    Institute of Scientific and Technical Information of China (English)

    HUANG Fu-xiang; WANG Xin-hua; ZHANG Jiong-ming; JI Chen-xi; FANG Yuan; YU Yan

    2008-01-01

    The solidification process of AISI 304 stainless steel during cooling at a rate of 0.05 K/s has been observed in situ using a confocal scanning laser microscope(CSLM).The results show that the δ phase appeared first in liquid steel,as the temperature decreased,the γ phase precipitated prior at δ-grain boundary at 1452.2℃,the liquid steel disappeared at 1431.3℃,and then theγphase precipitated on the δ ferrite.Based on the Scheil-GulliVer solidification model,the solidification processes of AISI 304 stainless steel are simulated using the Scheil model in Thermo-Calc.and the simulation results agree well with the results observed in the experiment.

  16. Potential for in situ chemical oxidation of acid extractable organics in oil sands process affected groundwater.

    Science.gov (United States)

    Sohrabi, V; Ross, M S; Martin, J W; Barker, J F

    2013-11-01

    The process of bitumen extraction from oil sands in Alberta, Canada leads to an accumulation of toxic acid-extractable organics (AEOs) in oil sands process water (OSPW). Infiltration of OSPW from tailings ponds and from their retaining sand dykes and subsequent transport towards surface water has occurred. Given the apparent lack of significant natural attenuation of AEOs in groundwater, remediation may be required. This laboratory study evaluates the potential use of unactivated persulfate and permanganate as in situ oxidation agents for remediation of AEOs in groundwater. Naphthenic acids (NAs; CnH2n+zO2), which are a component of the acutely toxic AEOs, were degraded by both oxidants in OSPW samples. Permanganate oxidation yielded some residual dissolved organic carbon (DOC) whereas persulfate mineralized the AEO compounds with less residual DOC. Acid-extractable organics from oxidized OSPW had essentially no Microtox toxicity.

  17. In Situ XRD Studies of the Process Dynamics During Annealing in Cold-Rolled Copper

    Science.gov (United States)

    Dey, Santu; Gayathri, N.; Bhattacharya, M.; Mukherjee, P.

    2016-09-01

    The dynamics of the release of stored energy during annealing along two different crystallographic planes, i.e., {111} and {220}, in deformed copper have been investigated using in situ X-ray diffraction measurements at 458 K and 473 K (185 °C and 200 °C). The study has been carried out on 50 and 80 pct cold-rolled Cu sheets. The microstructures of the rolled samples have been characterized using optical microscopy and electron backscattered diffraction measurements. The microstructural parameters were evaluated from the X-ray diffractogram using the Scherrer equation and the modified Rietveld method. The stored energy along different planes was determined using the modified Stibitz formula from the X-ray peak broadening, and the bulk stored energy was evaluated using differential scanning calorimetry. The process dynamics of recovery and recrystallization as observed through the release of stored energy have been modeled as the second-order and first-order processes, respectively.

  18. Spallation Process of Thermally Grown Oxides by In-Situ CCD Monitoring Technique

    Institute of Scientific and Technical Information of China (English)

    QI Yu-hong; Philippe Lours; Yannick Le Maoult

    2009-01-01

    In cooling process of Fe-Cr-AI alloy oxidized at 1 300 ℃, the effect of cooling speed and exposure time on oxide spalled area fraction and successive variety of the spalled region were studied by investigating evolvement of the thermally grown oxide using in-situ CCD monitoring technique. The results showed that oxide spallation can be re-strained by controlling cooling speed and the critical temperature drop of spallation initiation which is closely related to the oxide thickness or exposure time, and the spallation process of a little region may be described in more detail as two routes:from the oxide/substrate interface micro-decohesion, micro-buckles, buckle spreading, buckle crack to spallation and from the interface micro-decohesion, micro-buckles, buckle crack and spallation to the residual oxide decohesion and spallation.

  19. Influence of Process Parameters on Coal Combustion Performance

    DEFF Research Database (Denmark)

    Lans, Robert Pieter Van Der

    The objective of this study is to improve the understanding of nitrogen oxide formation and carbon burnout during the combustion of pulverized coal, and to contribute to addressing the potential of chemical engineering models for the prediction of furnace temperatures, NO emissions and the amount...... of carbon in ash. To this purpose, the effect of coal quality on NO and burnout has been investigated experimentally, a radiation heat balance has been developed based on simple chemical engineering methodology, and a mixing study has been conducted in order to describe the near burner macro mixing in terms...... with self-sustaining flames, while extensions are made to full scale boilers and furnace modeling. Since coal combustion and flame aerodynamics are reviewed elsewhere, these phenomena are only treated briefly. The influence of coal type and process conditions on NO formation and carbon burnout has been...

  20. Reconstruction of an engine combustion process with a neural network

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, P.J.; Gu, F.; Ball, A.D. [School of Engineering, University of Manchester, Manchester (United Kingdom)

    1997-12-31

    The cylinder pressure waveform in an internal combustion engine is one of the most important parameters in describing the engine combustion process. It is used for a range of diagnostic tasks such as identification of ignition faults or mechanical wear in the cylinders. However, it is very difficult to measure this parameter directly. Never-the-less, the cylinder pressure may be inferred from other more readily obtainable parameters. In this presentation it is shown how a Radial Basis Function network, which may be regarded as a form of neural network, may be used to model the cylinder pressure as a function of the instantaneous crankshaft velocity, recorded with a simple magnetic sensor. The application of the model is demonstrated on a four cylinder DI diesel engine with data from a wide range of speed and load settings. The prediction capabilities of the model once trained are validated against measured data. (orig.) 4 refs.

  1. Nanomaterial processing for multifunctional patterned composites for in situ sensing applications

    Science.gov (United States)

    Melrose, Zachary R.

    The increasing performance demands on composite materials have stimulated the development of new approaches and manufacturing techniques to integrate various system functionalities within the composite structure. Opportunity exists to produce smart, self-sensing composites, by altering the microstructure of the composite where sensors can be patterned for assessing damage locality and severity. Introduction of nanomaterials into continuous fiber-reinforced composites either at the fiber/matrix interface or within the polymer matrix enables further tailoring of mechanical and electrical properties. Carbon nanotubes have been studied extensively for modifying the mechanical and physical properties of fiber composites. Recently graphene has generated scientific and technical interest due to potential lower raw material costs and ease of processing. This work studies graphene nano-platelet processing parameters to determine the suitability of graphene nanocomposites for in situ sensing applications. Processing parameters for optimizing the piezoresistive response of graphene nano-platelet composites for in situ sensing applications are determined and applied in for the development of a patterning media suitable for deposition onto glass fibers. A new approach to selectively modify the electrical properties of composite fibers is employed to selectively deposit carbon nanotube and graphene nano-platelet enhanced patterning media through an adapted screen printing process. These nano-modified depositions create hierarchical patterns of piezoresistive sensors as fully integrated components and form a distributed sensor network at the fiber/matrix interface. New analysis tools for resistance based sensing techniques are applied to nanocomposites and patterned unidirectional hybrid nanocomposites to assess damage onset and accumulation. The sensitivity of the electrical response for the graphene nano-platelet is compared with the electrical response of the carbon nanotube

  2. Kinetic analysis of manure pyrolysis and combustion processes.

    Science.gov (United States)

    Fernandez-Lopez, M; Pedrosa-Castro, G J; Valverde, J L; Sanchez-Silva, L

    2016-12-01

    Due to the depletion of fossil fuel reserves and the environmental issues derived from their use, biomass seems to be an excellent source of renewable energy. In this work, the kinetics of the pyrolysis and combustion of three different biomass waste samples (two dairy manure samples before (Pre) and after (Dig R) anaerobic digestion and one swine manure sample (SW)) was studied by means of thermogravimetric analysis. In this work, three iso-conversional methods (Friedman, Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS)) were compared with the Coats-Redfern method. The Ea values of devolatilization stages were in the range of 152-170kJ/mol, 148-178kJ/mol and 156-209kJ/mol for samples Pre, Dig R and SW, respectively. Concerning combustion process, char oxidation stages showed lower Ea values than that obtained for the combustion devolatilization stage, being in the range of 140-175kJ/mol, 178-199kJ/mol and 122-144kJ/mol for samples Pre, Dig R and SW, respectively. These results were practically the same for samples Pre and Dig R, which means that the kinetics of the thermochemical processes were not affected by anaerobic digestion. Finally, the distributed activation energy model (DAEM) and the pseudo-multi component stage model (PMSM) were applied to predict the weight loss curves of pyrolysis and combustion. DAEM was the best model that fitted the experimental data. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. In situ characterization of uranium and americium oxide solid solution formation for CRMP process: first combination of in situ XRD and XANES measurements.

    Science.gov (United States)

    Caisso, Marie; Picart, Sébastien; Belin, Renaud C; Lebreton, Florent; Martin, Philippe M; Dardenne, Kathy; Rothe, Jörg; Neuville, Daniel R; Delahaye, Thibaud; Ayral, André

    2015-04-14

    Transmutation of americium in heterogeneous mode through the use of U1-xAmxO2±δ ceramic pellets, also known as Americium Bearing Blankets (AmBB), has become a major research axis. Nevertheless, in order to consider future large-scale deployment, the processes involved in AmBB fabrication have to minimize fine particle dissemination, due to the presence of americium, which considerably increases the risk of contamination. New synthesis routes avoiding the use of pulverulent precursors are thus currently under development, such as the Calcined Resin Microsphere Pelletization (CRMP) process. It is based on the use of weak-acid resin (WAR) microspheres as precursors, loaded with actinide cations. After two specific calcinations under controlled atmospheres, resin microspheres are converted into oxide microspheres composed of a monophasic U1-xAmxO2±δ phase. Understanding the different mechanisms during thermal conversion, that lead to the release of organic matter and the formation of a solid solution, appear essential. By combining in situ techniques such as XRD and XAS, it has become possible to identify the key temperatures for oxide formation, and the corresponding oxidation states taken by uranium and americium during mineralization. This paper thus presents the first results on the mineralization of (U,Am) loaded resin microspheres into a solid solution, through in situ XAS analysis correlated with HT-XRD.

  4. Focused beam reflectance measurement as a tool for in situ monitoring of the lactose crystallization process.

    Science.gov (United States)

    Pandalaneni, K; Amamcharla, J K

    2016-07-01

    Lactose accounts for about 75 and 85% of the solids in whey and deproteinized whey, respectively. Production of lactose is usually carried out by a process called crystallization. Several factors including rate of cooling, presence of impurities, and mixing speed influence the crystal size characteristics. To optimize the lactose crystallization process parameters to maximize the lactose yield, it is important to monitor the crystallization process. However, efficient in situ tools to implement at concentrations relevant to the dairy industry are lacking. The objective of the present work was to use a focused beam reflectance measurement (FBRM) system for in situ monitoring of lactose crystallization at supersaturated concentrations (wt/wt) 50, 55, and 60% at 20 and 30°C. The FBRM data were compared with Brix readings collected using a refractometer during isothermal crystallization. Chord length distributions obtained from FBRM in the ranges of crystals) and 50 to 300 µm (coarse crystals) were recorded and evaluated in relation to the extent of crystallization and rate constants deduced from the refractometer measurements. Extent of crystallization and rate constants increased with increasing supersaturation concentration and temperature. The measured fine crystal counts from FBRM increased at higher supersaturated concentration and temperature during isothermal crystallization. On the other hand, coarse counts were observed to increase with decreasing supersaturated concentration and temperature. Square weighted chord length distribution obtained from FBRM showed that as concentration increased, a decrease in chord lengths occurred at 20°C and similar observations were made from microscopic images. The robustness of FBRM in understanding isothermal lactose crystallization at various concentrations and temperatures was successfully assessed in the study. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  5. Electrochemical processes for in-situ treatment of contaminated soils. 1998 annual progress report

    Energy Technology Data Exchange (ETDEWEB)

    Huang, C.P.

    1998-06-01

    'This research project is to develop electrochemical processes for in-situ treatment of contaminated soils. Specifically, it is to study electrokinetic (EK) and electro-Fento (EF) processes and to integrate these processes for the treatment of soils containing mixed contaminants. The objectives are: (1) To study important parameters controlling the mobilization and the transport of selected organics and metals in soils by the electrokinetic (EK) process. Factors to be studied include field strength, pH, ionic strength, soil washing agents, types of organic and metal contaminants, and soil surface properties such as cation exchange capacity(CEC), soil organic content, soil moisture content, soil composition, and surface charge. (2) To study the important factors governing the oxidation of selected organic contaminants by the electro-Fenton (EF) process. Parameters such as pH, surface area and the configuration of working electrode, oxygen concentration, ferrous ion, and temperature that may affect the performance of the EF process will be investigated. (3) To understand the mechanism of the oxidation of selected organic contaminants by the electro-Fenton oxidation process.'

  6. In situ observation of deformation processes in nanocrystalline face-centered cubic metals.

    Science.gov (United States)

    Kobler, Aaron; Brandl, Christian; Hahn, Horst; Kübel, Christian

    2016-01-01

    The atomistic mechanisms active during plastic deformation of nanocrystalline metals are still a subject of controversy. The recently developed approach of combining automated crystal orientation mapping (ACOM) and in situ straining inside a transmission electron microscope was applied to study the deformation of nanocrystalline Pd x Au1- x thin films. This combination enables direct imaging of simultaneously occurring plastic deformation processes in one experiment, such as grain boundary motion, twin activity and grain rotation. Large-angle grain rotations with ≈39° and ≈60° occur and can be related to twin formation, twin migration and twin-twin interaction as a result of partial dislocation activity. Furthermore, plastic deformation in nanocrystalline thin films was found to be partially reversible upon rupture of the film. In conclusion, conventional deformation mechanisms are still active in nanocrystalline metals but with different weighting as compared with conventional materials with coarser grains.

  7. In-situ investigations of magnetron sputtering processes with laboratory X-ray equipment

    Energy Technology Data Exchange (ETDEWEB)

    Ringpfeil, Clemens [Fachbereich C-Physik, Bergische Universitaet Wuppertal, Gaussstr. 20, D-42097 Wuppertal (Germany)]. E-mail: Clemens@physik.uni-wuppertal.de; Luetzenkirchen-Hecht, Dirk [Fachbereich C-Physik, Bergische Universitaet Wuppertal, Gaussstr. 20, D-42097 Wuppertal (Germany); Frahm, Ronald [Fachbereich C-Physik, Bergische Universitaet Wuppertal, Gaussstr. 20, D-42097 Wuppertal (Germany)

    2007-05-23

    An Fe-Al duplex film was prepared on a Si(111)-wafer by sputter deposition in a vacuum chamber with two integrated small magnetron sources. The chamber allows the in-situ investigation of such sputtering processes using grazing incidence X-ray reflectivity, X-ray scattering measurements and X-ray diffraction. We will present details of the new cell and present the first results obtained using reflectivity measurements of the Fe-Al thin films. Here we will focus on the detailed evaluation of the specular reflectivity data of the iron films only, which clearly indicates the presence of an iron oxide, the density and roughness of which were determined and their changes with the film thickness were discussed in the framework of thin film growth models.

  8. In Situ Observation for Abnormal Grain Coarsening in Vacuum-Carburizing Process

    Science.gov (United States)

    Yogo, Yasuhiro; Tanaka, Kouji

    2014-06-01

    An in situ observation method was developed to investigate abnormal grain coarsening which occurs around the surface of steel during the vacuum-carburizing process. In this method, diffusion of carbon atoms in the vacuum carburizing was simulated by a cementite and steel diffusion couple. Abnormal grain coarsening, which appeared around the cementite and steel interface, was observed by a confocal scanning laser microscope. With this method, it was observed that when holding time was 60 seconds, the temperature at which the abnormal grain coarsening appeared in a specimen was higher when carburized than the temperature when not carburized. On the contrary, when holding time was 120 seconds, the temperature at which the abnormal grain coarsening appeared in a specimen was 10 K to 20 K lower than that in a non-carburized specimen. The validity of the observed results was confirmed by the calculated NbC fraction using Nb solubility and measured carbon content.

  9. In situ observation of magnetic orientation process of feeble magnetic materials under high magnetic fields

    Directory of Open Access Journals (Sweden)

    Noriyuki Hirota et al

    2008-01-01

    Full Text Available An in situ microscopic observation of the magnetic orientation process of feeble magnetic fibers was carried out under high magnetic fields of up to 10 T using a scanning laser microscope. In the experiment, carbon fibers and needle-like titania fibers with a length of 1 to 20 μm were used. The fibers were observed to gradually orient their axes parallel to the direction of the magnetic field. The orientation behavior of the sample fibers was evaluated on the basis of the measured duration required for a certain angular variation. As predicted from the theoretical consideration, it was confirmed that the duration required for a certain angular variation normalized by the viscosity of the fluid is described as a function of the fiber length. The results obtained here appear useful for the consideration of the magnetic orientation of materials suspended in a static fluid.

  10. In-situ water vaporization improves bitumen production during electrothermal processes

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J. [Calgary Univ., AB (Canada); McGee, B. [E-T Energy, Calgary, AB (Canada); Kantzas, A. [Calgary Univ., AB (Canada). Tomographic Imaging and Porous Media Laboratory

    2008-10-15

    Electro-thermal processes are now being considered as an alternative or complementary process to steam injection processes. This study used an in situ vaporized water process to optimize electrothermal processes for steam injection enhanced oil recovery (EOR). A simulation tool was used to model electro-thermal processes in an Athabasca oil sands reservoir. Incremental oil recovery was estimated based on a 3-block conceptual model. A field scale model was then used to investigate the effects of electrode spacing, water injection rates, and electrical heating rates on bitumen recovery. Results of the simulation studies were then analyzed using a statistical tool in order to determine optimal conditions for maximizing bitumen production. Results of the study showed that incremental recovery using the water vaporization technique resulted in oil recovery rates of 25 per cent original oil in place (OOIP). Sensitivity analyses showed that medium electrical heating rates, low water injection rates, and small spacings between electrodes maximized bitumen production rates. It was concluded that the technique can be used alone or combined with other methods to economically produce bitumens. 2 refs., 7 tabs., 9 figs.

  11. Combustion characteristics of aluminium-iron oxidein SHS-gravitational process

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In order to get high quality of products, the combustion of aluminium-iron oxide thermite in SHS-gravitational process must be under control. The effects of thermite filling density, hole in thermite and inclined angle of pipe on combustion rate were studied. It shows that the combustion rate decreases with the decrease of filling density. The thermite combusts downwards the pipe much more quickly if there are holes in the thermite. And the combustion rate increases with the increase of the inclined angle of pipe. The experiment results show that the combustion of thermite is predominantly controlled by gas phasereaction, which is attributed to the high temperature of the thermitecombustion.

  12. PCDD/PCDF reduction by the co-combustion process.

    Science.gov (United States)

    Lee, Vinci K C; Cheung, Wai-Hung; McKay, Gordon

    2008-01-01

    A novel process, termed the co-combustion process, has been developed and designed to utilise the thermal treatment of municipal solid waste (MSW) in cement clinker production and reduce PCDD/PCDF emissions. To test the conceptual design; detailed engineering design of the process and equipment was performed and a pilot plant was constructed to treat up to 40 tonnes MSW per day. The novel process features included several units external to the main traditional cement rotary kiln: an external calcinations unit in which the hot gas calcined the limestone thus making significant energy savings for this chemical reaction; the lime generated was used in a second chamber to act as a giant acid gas scrubber to remove SOx and particularly HCl (a source of chloride); an external rotary kiln and secondary combustion unit capable of producing a hot gas at 1200 degrees C; a gas cooler to simulate a boiler turbogenerator set for electricity generation; the incorporation of some of the bottom ash, calcined lime and dust collector solids into the cement clinker. A PCDD/PCDF inventory has been completed for the entire process and measured PCDD/PCDF emissions were 0.001 ng I-TEQ/Nm(3) on average which is 1% of the best practical means [Hong Kong Environmental Protection Department, 2001. A guidance note on the best practicable means for incinerators (municipal waste incineration), BPM12/1] MSW incineration emission limit values.

  13. Modeling and Analysis of the Reverse Water Gas Shift Process for In-Situ Propellant Production

    Science.gov (United States)

    Whitlow, Jonathan E.

    2000-01-01

    This report focuses on the development of mathematical models and simulation tools developed for the Reverse Water Gas Shift (RWGS) process. This process is a candidate technology for oxygen production on Mars under the In-Situ Propellant Production (ISPP) project. An analysis of the RWGS process was performed using a material balance for the system. The material balance is very complex due to the downstream separations and subsequent recycle inherent with the process. A numerical simulation was developed for the RWGS process to provide a tool for analysis and optimization of experimental hardware, which will be constructed later this year at Kennedy Space Center (KSC). Attempts to solve the material balance for the system, which can be defined by 27 nonlinear equations, initially failed. A convergence scheme was developed which led to successful solution of the material balance, however the simplified equations used for the gas separation membrane were found insufficient. Additional more rigorous models were successfully developed and solved for the membrane separation. Sample results from these models are included in this report, with recommendations for experimental work needed for model validation.

  14. Sustained release of risperidone from biodegradable microspheres prepared by in-situ suspension-evaporation process.

    Science.gov (United States)

    An, Taekun; Choi, Juhyuen; Kim, Aram; Lee, Jin Ho; Nam, Yoonjin; Park, Junsung; Sun, Bo kyung; Suh, Hearan; Kim, Cherng-ju; Hwang, Sung-Joo

    2016-04-30

    Risperidone-loaded poly (D,L-lactide-co-glycolide) (PLGA) microspheres were prepared with a suspension-evaporation process with an aqueous suspension containing an in situ-formed aluminum hydroxide inorganic gel (SEP-AL process) and evaluated for encapsulation efficiency, particle size, surface morphology, glass transition temperature, in vitro drug release profile, and in vivo behavior. The SEP-AL microspheres were compared with conventional oil-in-water (O/W) emulsion solvent evaporation method using polyvinylalcohol (PVA) as an emulsifier (CP-PVA process). The microspheres were spherical in shape. DSC measurements showed that risperidone crystallinity was greatly reduced due to the homogeneous distribution of risperidone in PLGA microspheres. In vitro drug release profile from the microspheres showed a sigmoidal pattern of negligible initial burst up to 24h and minimal release (time-lag) for 7 days. After the lag phase, slow release took a place up to 25 days and then rapid release occurred sharply for 1 week. In vivo rat pharmacokinetic profile from the microspheres showed very low blood concentration level at the initial phase (up to 24h) followed by the latent phase up to 21 days. At the 3rd week, main phase started and the blood concentration of the drug increased up to the 5th week, and then gradually decreased. The risperidone-loaded PLGA microspheres produced by SEP-AL process showed excellent controlled release characteristics for the effective treatment of schizophrenia patients.

  15. In situ treatment of mixed contaminants in groundwater: Review of candidate processes

    Energy Technology Data Exchange (ETDEWEB)

    Korte, N.E. [ed.] [Oak Ridge National Lab., Grand Junction, CO (United States); Siegrist, R.L. [ed.] [Oak Ridge National Lab., TN (United States); Ally, M. [and others

    1994-10-01

    This document describes the screening and preliminary evaluation of candidate treatment for use in treating mixed contaminants volatile organic compounds (VOCs) and radionuclides in groundwater. Treating mixed contaminants presents unusual difficulties. Typically, VOCs are the most abundant contaminants, but the presence of radionuclides results in additional health concerns that must be addressed, usually by a treatment approach different from that used for VOCs. Furthermore, the presence of radionuclides may yield mixed solid wastes if the VOCs are treated by conventional means. These issues were specifically addressed in the evaluation of candidate treatment processes for testing in this program. Moreover, because no research or early development of a particular process would be performed, the technology review also focused on technologies that could be readily adapted and integrated for use with mixed contaminants. The objective is to couple emerging or available processes into treatment modules for use in situ. The three year project, to be completed in September 1996, includes a full-scale field demonstration. The findings reported in this document encompass all activities through the treatment process evaluations.

  16. Characterising Combustion in Diesel Engines: using parameterised finite stage cylinder process models

    NARCIS (Netherlands)

    Ding, Y.

    2011-01-01

    Characterising combustion of diesel engines is not only necessary when researching the instantaneous combustion phenomena but also when investigating the change of the combustion process under variable engine operating conditions. An effective way to achieve this goal is to parameterize the

  17. Ignition and wave processes in combustion of solids

    CERN Document Server

    Rubtsov, Nickolai M; Alymov, Michail I

    2017-01-01

    This book focuses on the application of classical combustion theory to ignition and flame propagation in solid-solid and gas-solid systems. It presents experimental investigations in the areas of local ignition, filtration combustion, self-propagating high temperature synthesis and nanopowders protection. The authors highlight analytical formulas used in different areas of combustion in solids and propose an approach based on classical combustion theory. The book attempts to analyze the basic approaches to understanding of solid-solid and solid - gas combustion presented in contemporary literature in a unified approach based on classical combustion theory. .

  18. In-situ real-time x-ray scattering for probing the processing-structure-performance relation

    KAUST Repository

    Smilgies, Detlef-M.

    2014-01-01

    © 2014 Materials Research Society. In-situ X-ray scattering methodology is discussed, in order to analyze the microstructure development of soft functional materials during coating, annealing, and drying processes in real-time. The relevance of a fundamental understanding of coating processes for future industrial production is pointed out.

  19. The size effect on solidification in eutectic bismuth-tin (Bi-Sn) nanowires by in-situ annealing processes.

    Science.gov (United States)

    Chen, Shih-Hsun; Wang, Chiu-Yen; Chen, Lih-Juann; Liu, Tzeng-Feng; Chaol, Chuen-Guang

    2010-10-01

    The size effects on solidification and the formation mechanism of the segmented eutectic Bi-43Sn nanowires during in situ annealing have been investigated. A directional solidification along the wire axis limits the segmented eutectic nanowire to arrange axially during the in situ annealing processes due to directional solidification. In 70 nm nanowires, the small size confines the convection in liquid, which results in differences in the microstructure and composition profiles between 70 and 200 nm nanowires. In the vacuum hydraulic pressure injection process, the directional cooling helps the formation of single crystal, and the isotropic solidification leads to polycrystalline microstructure.

  20. New approaches for description of nitrogen chemistry in combustion processes

    Energy Technology Data Exchange (ETDEWEB)

    Hupa, M.; Kilpinen, P.; Nordstroem, T. [Aabo Akademi, Turku (Finland). Combustion Chemistry Research Group

    1997-10-01

    The aim of the project is to assist in development of more efficient in-furnace control methods for nitrogen oxide emission from energy conversion technologies based on combustion and/or gasification. Main emphasis in put on technologies such as fluidized bed combustion (CFBC, BFBC) and combined cycle processes (PFBC, IGCC). The project consists of two parts: (a) detailed kinetic elementary reaction modelling and (b) prediction of NO{sub x} emission from full scale combustors. The following topics have been studied during 1996: (a) Detailed kinetic modelling Effect of HCl on CO burn-out under FBC freeboard conditions. Effect of pressure on the Thermal DeNO{sub x} process under PFBC conditions. Mechanism of NH{sub 3} destruction to N{sub 2} by selective oxidation (SO): -the importance of formation of NO{sub 2} from NO and O{sub 2} at low temperatures. (b) Prediction of NO{sub x} emission from full scale combustors Prediction of NO{sub x} emission from BFBC freeboard: a case study using flow tubes and detailed chemistry. The work has been made partly in collaboration with VTT Energy (projects 213 and 214) and Tampere University of Technology (project 210). (orig.)

  1. Magic angle spinning nuclear magnetic resonance apparatus and process for high-resolution in situ investigations

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Jian Zhi; Sears, Jr., Jesse A.; Hoyt, David W.; Mehta, Hardeep S.; Peden, Charles H. F.

    2015-11-24

    A continuous-flow (CF) magic angle sample spinning (CF-MAS) NMR rotor and probe are described for investigating reaction dynamics, stable intermediates/transition states, and mechanisms of catalytic reactions in situ. The rotor includes a sample chamber of a flow-through design with a large sample volume that delivers a flow of reactants through a catalyst bed contained within the sample cell allowing in-situ investigations of reactants and products. Flow through the sample chamber improves diffusion of reactants and products through the catalyst. The large volume of the sample chamber enhances sensitivity permitting in situ .sup.13C CF-MAS studies at natural abundance.

  2. Fabrication and characterization of borocarbide thin films grown by in-situ process

    CERN Document Server

    Arisawa, S; Togano, K

    1999-01-01

    We have reported on the fabrication of thin films of YNi sub 2 B sub 2 C for the first time. The process, however, requires the post-annealing at 1050 .deg. C. It is preferable to avoid such a high temperature for practical device applications and we are aiming at establishing an in-situ process at lower temperatures. To obtain films with higher T sub c , it is very important to know the relationship between what we choose as substrates and what we get on them. Three kinds of substrates, polished MgO, unpolished MgO, and polished SrTiO sub 3 were adopted. As for former 2 kinds of substates, superconductive films were successfully fabricated with the T sub c of approx 11K. Further, we discuss the fabrication of thin films of YPd sub 2 B sub 2 C on SrTiO sub 3 substrate. We tried to synthesize the films of the Pd system by RF sputtering technique as well. So far, it is uncertain whether or not the 1221 phase exists in the films. However, the slight reduction of the resistance was observed at 23 K, which is almo...

  3. Monitoring biodegradation of diesel fuel in bioventing processes using in situ respiration rate.

    Science.gov (United States)

    Lee, T H; Byun, I G; Kim, Y O; Hwang, I S; Park, T J

    2006-01-01

    An in situ measuring system of respiration rate was applied for monitoring biodegradation of diesel fuel in a bioventing process for bioremediation of diesel contaminated soil. Two laboratory-scale soil columns were packed with 5 kg of soil that was artificially contaminated by diesel fuel as final TPH (total petroleum hydrocarbon) concentration of 8,000 mg/kg soil. Nutrient was added to make a relative concentration of C:N:P = 100:10:1. One soil column was operated with continuous venting mode, and the other one with intermittent (6 h venting/6 h rest) venting mode. On-line O2 and CO2 gas measuring system was applied to measure O2 utilisation and CO2 production during biodegradation of diesel for 5 months. Biodegradation rate of TPH was calculated from respiration rate measured by the on-line gas measuring system. There were no apparent differences between calculated biodegradation rates from two columns with different venting modes. The variation of biodegradation rates corresponded well with trend of the remaining TPH concentrations comparing other biodegradation indicators, such as C17/pristane and C18/phytane ratio, dehydrogenase activity, and the ratio of hydrocarbon utilising bacteria to total heterotrophic bacteria. These results suggested that the on-line measuring system of respiration rate would be applied to monitoring biodegradation rate and to determine the potential applicability of bioventing process for bioremediation of oil contaminated soil.

  4. Aquifer restoration at in-situ leach uranium mines: evidence for natural restoration processes

    Energy Technology Data Exchange (ETDEWEB)

    Deutsch, W.J.; Serne, R.J.; Bell, N.E.; Martin, W.J.

    1983-04-01

    Pacific Northwest Laboratory conducted experiments with aquifer sediments and leaching solution (lixiviant) from an in-situ leach uranium mine. The data from these laboratory experiments and information on the normal distribution of elements associated with roll-front uranium deposits provide evidence that natural processes can enhance restoration of aquifers affected by leach mining. Our experiments show that the concentration of uranium (U) in solution can decrease at least an order of magnitude (from 50 to less than 5 ppM U) due to reactions between the lixiviant and sediment, and that a uranium solid, possibly amorphous uranium dioxide, (UO/sub 2/), can limit the concentration of uranium in a solution in contact with reduced sediment. The concentrations of As, Se, and Mo in an oxidizing lixiviant should also decrease as a result of redox and precipitation reactions between the solution and sediment. The lixiviant concentrations of major anions (chloride and sulfate) other than carbonate were not affected by short-term (less than one week) contact with the aquifer sediments. This is also true of the total dissolved solids level of the solution. Consequently, we recommend that these solution parameters be used as indicators of an excursion of leaching solution from the leach field. Our experiments have shown that natural aquifer processes can affect the solution concentration of certain constituents. This effect should be considered when guidelines for aquifer restoration are established.

  5. A new application of passive samplers as indicators of in-situ biodegradation processes.

    Science.gov (United States)

    Belles, Angel; Alary, Claire; Criquet, Justine; Billon, Gabriel

    2016-12-01

    In this paper, a method for evaluating the in-situ degradation of nitro polycyclic aromatic hydrocarbons (nitro-PAH) in sediments is presented. The methodology is adapted from the passive sampler technique, which commonly uses the dissipation rate of labeled compounds loaded in passive sampler devices to sense the environmental conditions of exposure. In the present study, polymeric passive samplers (made of polyethylene strips) loaded with a set of labeled polycyclic aromatic hydrocarbons (PAH) and nitro-PAH were immersed in sediments (in field and laboratory conditions) to track the degradation processes. This approach is theoretically based on the fact that a degradation process induces a steeper concentration gradient of the labeled compounds in the surrounding sediment, thereby increasing their compound dissipation rates compared with their dissipation in abiotic conditions. Postulating that the degradation magnitude is the same for the labeled compounds loaded in polyethylene strips and for their native homologs that are potentially present in the sediment, the field degradation of 3 nitro-PAH (2-nitro-fluorene, 1-nitro-pyrene, 6-nitro-chrysene) was semi-quantitatively analyzed using the developed method.

  6. Advanced in-situ electron-beam lithography for deterministic nanophotonic device processing

    Energy Technology Data Exchange (ETDEWEB)

    Kaganskiy, Arsenty; Gschrey, Manuel; Schlehahn, Alexander; Schmidt, Ronny; Schulze, Jan-Hindrik; Heindel, Tobias; Rodt, Sven, E-mail: srodt@physik.tu-berlin.de; Reitzenstein, Stephan [Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstraße 36, D-10623 Berlin (Germany); Strittmatter, André [Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstraße 36, D-10623 Berlin (Germany); Otto-von-Guericke Universität Magdeburg, Universitätsplatz 2, D-39106 Magdeburg (Germany)

    2015-07-15

    We report on an advanced in-situ electron-beam lithography technique based on high-resolution cathodoluminescence (CL) spectroscopy at low temperatures. The technique has been developed for the deterministic fabrication and quantitative evaluation of nanophotonic structures. It is of particular interest for the realization and optimization of non-classical light sources which require the pre-selection of single quantum dots (QDs) with very specific emission features. The two-step electron-beam lithography process comprises (a) the detailed optical study and selection of target QDs by means of CL-spectroscopy and (b) the precise retrieval of the locations and integration of target QDs into lithographically defined nanostructures. Our technology platform allows for a detailed pre-process determination of important optical and quantum optical properties of the QDs, such as the emission energies of excitonic complexes, the excitonic fine-structure splitting, the carrier dynamics, and the quantum nature of emission. In addition, it enables a direct and precise comparison of the optical properties of a single QD before and after integration which is very beneficial for the quantitative evaluation of cavity-enhanced quantum devices.

  7. Solution-Processing of Organic Solar Cells: From In Situ Investigation to Scalable Manufacturing

    KAUST Repository

    Abdelsamie, Maged

    2016-12-05

    implementation of organic solar cells with high efficiency and manufacturability. In this dissertation, we investigate the mechanism of the BHJ layer formation during solution processing from common lab-based processes, such as spin-coating, with the aim of understanding the roles of materials, formulations and processing conditions and subsequently using this insight to enable the scalable manufacturing of high efficiency organic solar cells by such methods as wire-bar coating and blade-coating. To do so, we have developed state-of-the-art in situ diagnostics techniques to provide us with insight into the thin film formation process. As a first step, we have developed a modified spin-coater which allows us to perform in situ UV-visible absorption measurements during spin coating and provides key insight into the formation and evolution of polymer aggregates in solution and during the transformation to the solid state. Using this method, we have investigated the formation of organic BHJs made of a blend of poly (3-hexylthiophene) (P3HT) and fullerene, reference materials in the organic solar cell field. We show that process kinetics directly influence the microstructure and morphology of the bulk heterojunction, highlighting the value of in situ measurements. We have investigated the influence of crystallization dynamics of a wide-range of small-molecule donors and their solidification pathways on the processing routes needed for attaining high-performance solar cells. The study revealed the reason behind the need of empirically-adopted processing strategies such as solvent additives or alternatively thermal or solvent vapor annealing for achieving optimal performance. The study has provided a new perspective to materials design linking the need for solvent additives or annealing to the ease of crystallization of small-molecule donors and the presence or absence of transient phases before crystallization. From there, we have extended our investigation to small-molecule (p

  8. Remediation of PCB-contaminated soils. Risk analysis of biological in situ processes

    Energy Technology Data Exchange (ETDEWEB)

    Rein, Arno

    2006-12-08

    effects on other soil organisms. Potential field release applications of in situ bioremediation using GMOs require performance control in the source zone (to ensure the functionality of the degradation process) and compliance monitoring, addressing contaminants, metabolites and GMOs. Detailed guidelines were compiled for respective tasks. (orig.)

  9. Electrochemically Modulated Gas/Liquid Separation Technology for In Situ Resource Utilization Process Streams Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this phase I program MicroCell Technologies, LLC (MCT) proposes to demonstrate the feasibility of an electrochemically modulated phase separator for in situ...

  10. Application of pulse combustion technology in spray drying process

    Directory of Open Access Journals (Sweden)

    I. Zbicinski

    2000-12-01

    Full Text Available The paper presents development of valved pulse combustor designed for application in drying process and drying tests performed in a specially built installation. Laser technique was applied to investigate the flow field and structure of dispersed phase during pulse combustion spray drying process. PDA technique was used to determine initial atomization parameters as well as particle size distribution, velocity of the particles, mass concentration of liquid phase in the cross section of spray stream, etc., in the drying chamber during drying tests. Water was used to estimate the level of evaporation and 5 and 10% solutions of sodium chloride to carry out drying tests. The Computational Fluid Dynamics technique was used to perform theoretical predictions of time-dependent velocity, temperature distribution and particle trajectories in the drying chamber. Satisfactory agreement between calculations and experimental results was found in certain regions of the drying chamber.

  11. In Situ Mass Spectrometric Monitoring of the Dynamic Electrochemical Process at the Electrode–Electrolyte Interface: a SIMS Approach

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhaoying; Zhang, Yanyan; Liu, Bingwen; Wu, Kui; Thevuthasan, Suntharampillai; Baer, Donald R.; Zhu, Zihua; Yu, Xiao-Ying; Wang, Fuyi

    2017-01-03

    The in situ molecular characterization of reaction intermediates and products at electrode-electrolyte interfaces is central to mechanistic studies of complex electrochemical processes, yet a great challenge. The coupling of electrochemistry (EC) and mass spectrometry (MS) has seen rapid development and found broad applicability in tackling challenges in analytical and bioanalytical chemistry. However, few truly in situ and real-time EC-MS studies have been reported at electrode-electrolyte interfaces. An innovative EC-MS coupling method named in situ liquid secondary ion mass spectrometry (SIMS) was recently developed by combining SIMS with a vacuum compatible microfluidic electrochemical device. Using this novel capability we report the first in situ elucidation of the electro-oxidation mechanism of a biologically significant organic compound, ascorbic acid (AA), at the electrode-electrolyte interface. The short-lived radical intermediate was successfully captured, which had not been detected directly before. Moreover, we demonstrated the power of this new technique in real-time monitoring of the formation and dynamic evolution of electrical double layers at the electrode-electrolyte interface. This work suggests further promising applications of in situ liquid SIMS in studying more complex chemical and biological events at the electrode-electrolyte interface.

  12. In Situ Mass Spectrometric Monitoring of the Dynamic Electrochemical Process at the Electrode-Electrolyte Interface: a SIMS Approach.

    Science.gov (United States)

    Wang, Zhaoying; Zhang, Yanyan; Liu, Bingwen; Wu, Kui; Thevuthasan, Suntharampillai; Baer, Donald R; Zhu, Zihua; Yu, Xiao-Ying; Wang, Fuyi

    2017-01-03

    The in situ molecular characterization of reaction intermediates and products at electrode-electrolyte interfaces is central to mechanistic studies of complex electrochemical processes, yet a great challenge. The coupling of electrochemistry (EC) and mass spectrometry (MS) has seen rapid development and found broad applicability in tackling challenges in analytical and bioanalytical chemistry. However, few truly in situ and real-time EC-MS studies have been reported at electrode-electrolyte interfaces. An innovative EC-MS coupling method named in situ liquid secondary ion mass spectrometry (SIMS) was recently developed by combining SIMS with a vacuum compatible microfluidic electrochemical device. Using this novel capability, we report the first in situ elucidation of the electro-oxidation mechanism of a biologically significant organic compound, ascorbic acid (AA), at the electrode-electrolyte interface. The short-lived radical intermediate was successfully captured, which had not been detected directly before. Moreover, we demonstrated the power of this new technique in real-time monitoring of the formation and dynamic evolution of electrical double layers at the electrode-electrolyte interface. This work suggests further promising applications of in situ liquid SIMS in studying more complex chemical and biological events at the electrode-electrolyte interface.

  13. Transport phenomena of reactive fluid flow in heterogeneous combustion processes.

    Science.gov (United States)

    Hung, W. S. Y.; Chen, C. S.; Haviland, J. K.

    1972-01-01

    A previously developed computer program was used to model two transient hybrid combustion processes involving tubes of solid Plexiglas. In the first study, representing combustion of a hybrid rocket, the oxidizing gas was oxygen, and calculations were continued sufficiently long to obtain steady-state values. Systematic variations were made in reaction rate constant, mass flow rate, and pressure, alternatively using constant and temperature dependent regression rate models for the fuel surface. Consistent results were obtained, as is evidenced by the values for the mass function of the reaction product and the flame temperature, for which plots are supplied. In the second study, fire initiation in a duct was studied, with an air mixture as the oxidizing gas. It was demonstrated that a satisfactory flame spread mechanism could be reproduced on the computer. In both of the above applications, the general, transient, two-dimensional conservation equations were represented, together with chemical reactions, solid-fuel interface conditions, and heat conduction in the solid fuel.

  14. Characterization of degeneration process in combustion instability based on dynamical systems theory.

    Science.gov (United States)

    Gotoda, Hiroshi; Okuno, Yuta; Hayashi, Kenta; Tachibana, Shigeru

    2015-11-01

    We present a detailed study on the characterization of the degeneration process in combustion instability based on dynamical systems theory. We deal with combustion instability in a lean premixed-type gas-turbine model combustor, one of the fundamentally and practically important combustion systems. The dynamic behavior of combustion instability in close proximity to lean blowout is dominated by a stochastic process and transits to periodic oscillations created by thermoacoustic combustion oscillations via chaos with increasing equivalence ratio [Chaos 21, 013124 (2011); Chaos 22, 043128 (2012)]. Thermoacoustic combustion oscillations degenerate with a further increase in the equivalence ratio, and the dynamic behavior leads to chaotic fluctuations via quasiperiodic oscillations. The concept of dynamical systems theory presented here allows us to clarify the nonlinear characteristics hidden in complex combustion dynamics.

  15. In situ Scanning Electron Microscopy of Silicon Anode Reactions in Lithium-Ion Batteries during Charge/Discharge Processes

    Science.gov (United States)

    Chen, Chih-Yao; Sano, Teruki; Tsuda, Tetsuya; Ui, Koichi; Oshima, Yoshifumi; Yamagata, Masaki; Ishikawa, Masashi; Haruta, Masakazu; Doi, Takayuki; Inaba, Minoru; Kuwabata, Susumu

    2016-10-01

    A comprehensive understanding of the charge/discharge behaviour of high-capacity anode active materials, e.g., Si and Li, is essential for the design and development of next-generation high-performance Li-based batteries. Here, we demonstrate the in situ scanning electron microscopy (in situ SEM) of Si anodes in a configuration analogous to actual lithium-ion batteries (LIBs) with an ionic liquid (IL) that is expected to be a functional LIB electrolyte in the future. We discovered that variations in the morphology of Si active materials during charge/discharge processes is strongly dependent on their size and shape. Even the diffusion of atomic Li into Si materials can be visualized using a back-scattering electron imaging technique. The electrode reactions were successfully recorded as video clips. This in situ SEM technique can simultaneously provide useful data on, for example, morphological variations and elemental distributions, as well as electrochemical data.

  16. Processing and characterization of in-situ aluminum bronze titanium carbide composites

    Science.gov (United States)

    Pillai, Balathandan S.

    The present study was carried out to develop a process for manufacturing in-situ aluminum bronze titanium carbide (TiC) friction drums using the centrifugal casting method and to characterize the material under optimum performance. The in-situ method of manufacturing is based on the reactive gas injection technique (RGI). The gas used in this study is high purity methane (CH 4). It was found that the methane gas injection time into the molten bath of aluminum bronze alloyed with titanium promotes the formation of titanium carbide (TiC) in the bronze matrix. The maximum amount of TiC incorporated in the matrix was 3.1 wt.%. This lead to 11.5 wt.% incorporation of TiC in the inner diameter of centrifugal castings as carbide particles drifted towards this region due to the centrifugal forces and their relatively low density. The hardness and strength of these composites when compared with the as cast condition was improved by heat treatment. However, the alloy ductility was decreased at the expense of the strength. It was found that the wear resistance properties of the composites were superior to those of pure cast and heat treated aluminum bronze currently in use. Optical and Scanning Electron Microscopy indicated that the composite surfaces did not scratch deeply when wearing against a hardened 4340 steel. The wear resistance of the as cast aluminum bronze was inferior to that of heat treated one. Moreover, the heat treated aluminum bronze showed a lack of high abrasion resistance. The frictional coefficient was relatively low for the as cast aluminum bronze as a result of adhesive wear behavior for the load and speed chosen in this present investigation. The corrosion studies showed that these composites do not lead to improved corrosion resistance in marine water environments. Apparently, there is a galvanic corrosion of TiC to bronze. In addition, pitting was observed on the corroded surfaces and increased with the volume fraction of TiC. Model validation was

  17. Remediation of PCB-contaminated soils. Risk analysis of biological in situ processes

    Energy Technology Data Exchange (ETDEWEB)

    Rein, Arno

    2006-12-08

    Biological in situ measures can be efficient and cost effective options for the remediation of contaminated sites. However, the accepted application requires a detailed and reliable analysis of potential impacts. An important objective is to quantify the potential of contaminant degradation and metabolite formation. This thesis addresses a quantitative multimedia risk assessment. Methodologies and tools were developed for this objective and applied to evaluate in situ bioremediation of soils contaminated with polychlorinated biphenyls (PCBs). Soil bacteria in conjunction with plant roots were addressed (rhizoremediation) with a focus on the use of genetically modified microorganisms (GMOs). PCBs are known to be harmful compounds that are ubiquitously distributed in the environment. PCB contaminations in soil and groundwater were identified as important problems. 209 different congeners are sterically possible, but not all are of environmental significance. PCB congeners of concern were evaluated with respect to their potential toxicity, environmental occurrence and mobility. For this objective, congener specific data on the toxicity potential and the frequency in environmental matrices were collected. To quantify the mobility potential, multimedia modelling was performed applying deterministic and probabilistic procedures. 56 PCB congeners of concern were evaluated, and multimedia risk assessments of PCB-contaminated soils should concentrate on this group. Kinetics parameters were specified for degradation experiments with individual PCB congeners in solution and different bacterial strains. These laboratory assays were performed with wild-type Burkholderia sp. strain LB400 and the genetically modified Pseudomonas fluorescens strains F113pcb and F113L::1180. The F113 derivatives demonstrated a good survival ability in willow (Salix sp.) rhizosphere (mesocosm experiments). Therefore, and due to high depletion rates, rhizoremediation with F113L::1180 and willow

  18. Microfluidic electrochemical device and process for chemical imaging and electrochemical analysis at the electrode-liquid interface in-situ

    Science.gov (United States)

    Yu, Xiao-Ying; Liu, Bingwen; Yang, Li; Zhu, Zihua; Marshall, Matthew J.

    2016-03-01

    A microfluidic electrochemical device and process are detailed that provide chemical imaging and electrochemical analysis under vacuum at the surface of the electrode-sample or electrode-liquid interface in-situ. The electrochemical device allows investigation of various surface layers including diffuse layers at selected depths populated with, e.g., adsorbed molecules in which chemical transformation in electrolyte solutions occurs.

  19. In-situ monitoring of potential enhanced DNA related processes using electrochemical quartz crystal microbalance with dissipation (EQCM-D)

    DEFF Research Database (Denmark)

    Quan, Xueling; Heiskanen, Arto; Tenje, Maria

    2014-01-01

    The effect of applied potential pulses on DNA functionalization (thiolated single stranded DNA) and hybridization processes has been monitored in-situ on gold surfaces using electrochemical quartz crystal microbalance with dissipation (EQCM-D). The applied potentials were chosen with respect to t...

  20. Process improvements for the supercritical in situ transesterification of carbonized algal biomass.

    Science.gov (United States)

    Levine, Robert B; Bollas, Alexandra; Savage, Phillip E

    2013-05-01

    This work focuses on the production of biodiesel from wet, lipid-rich algal biomass using a two-step process involving hydrothermal carbonization (HTC) and supercritical in situ transesterification (SC-IST). Algal hydrochars produced by HTC were reacted in supercritical ethanol to determine the effects of reaction temperature, time, ethanol loading, water content, and pressure on the yield of fatty acid ethyl esters (FAEE). Reaction temperatures above 275 °C resulted in substantial thermal decomposition of unsaturated FAEE, thereby reducing yields. At 275 °C, time and ethanol loading had a positive impact on FAEE yield while increasing reaction water content and pressure reduced yields. FAEE yields as high as 79% with a 5:1 ethanol:fatty acid (EtOH:FA) molar ratio (150 min) and 89% with a 20:1 EtOH:FA molar ratio (180 min) were achieved. This work demonstrates that nearly all lipids within algal hydrochars can be converted into biodiesel through SC-IST with only a small excess of alcohol.

  1. Quantifying bulk and surface recombination processes in nanostructured water splitting photocatalysts via in situ ultrafast spectroscopy.

    Science.gov (United States)

    Appavoo, Kannatassen; Liu, Mingzhao; Black, Charles T; Sfeir, Matthew Y

    2015-02-11

    A quantitative description of recombination processes in nanostructured semiconductor photocatalysts-one that distinguishes between bulk (charge transport) and surface (chemical reaction) losses-is critical for advancing solar-to-fuel technologies. Here we present an in situ experimental framework that determines the bias-dependent quantum yield for ultrafast carrier transport to the reactive interface. This is achieved by simultaneously measuring the electrical characteristics and the subpicosecond charge dynamics of a heterostructured photoanode in a working photoelectrochemical cell. Together with direct measurements of the overall incident-photon-to-current efficiency, we illustrate how subtle structural modifications that are not perceivable by conventional X-ray diffraction can drastically affect the overall photocatalytic quantum yield. We reveal how charge carrier recombination losses occurring on ultrafast time scales can limit the overall efficiency even in nanostructures with dimensions smaller than the minority carrier diffusion length. This is particularly true for materials with high carrier concentration, where losses as high as 37% are observed. Our methodology provides a means of evaluating the efficacy of multifunctional designs where high overall efficiency is achieved by maximizing surface transport yield to near unity and utilizing surface layers with enhanced activity.

  2. Chemical Processes Related to Combustion in Fluidised Bed

    Energy Technology Data Exchange (ETDEWEB)

    Steenari, Britt-Marie; Lindqvist, Oliver [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Environmental Inorganic Chemistry

    2002-12-01

    with evaluation of other biomass ash particles and, as an extension, the speciation of Cu and Zn will be studied as well. Ash fractions from combustion of MSW in a BFB boiler have been investigated regarding composition and leaching properties, i.e. environmental impact risks. The release of salts from the cyclone ash fraction can be minimised by the application of a simple washing process, thus securing that the leaching of soluble substances stays within the regulative limits. The MSW ash - water systems contain some interesting chemical issues, such as the interactions between Cr(VI) and reducing substances like Al-metal. The understanding of such chemical processes is important since it gives a possibility to predict effects of a change in ash composition. An even more detailed understanding of interactions between a solution containing ions and particle surfaces can be gained by theoretical modelling. In this project (and with additional unding from Aangpannefoereningens Forskningsstiftelse) a theoretical description of ion-ion interactions and the solid-liquid-interface has been developed. Some related issues are also included in this report. The publication of a paper on the reactions of ammonia in the presence of a calcining limestone surface is one of them. A review paper on the influence of combustion conditions on the properties of fly ash and its applicability as a cement replacement in concrete is another. The licentiate thesis describing the sampling and measurement of Cd in flue gas is also included since it was finalised during the present period. A co-operation project involving the Geology Dept. at Goeteborg Univ. and our group is briefly discussed. This project concerns the utilisation of granules produced from wood ash and dolomite as nutrient source for forest soil. Finally, the plans for our flue gas simulator facility are discussed.

  3. Cyanobacteria to Link Closed Ecological Systems and In-Situ Resources Utilization Processes

    Science.gov (United States)

    Brown, Igor

    Introduction: A major goal for the Vision of Space Exploration is to extend human presence across the solar sys-tem. With current technology, however, all required consumables for these missions (propellant, air, food, water) as well as habitable volume and shielding to support human explorers will need to be brought from Earth. In-situ pro-duction of consumables (In-Situ Resource Utilization-ISRU) will significantly facilitate current plans for human ex-ploration and colonization of the solar system, especially by reducing the logistical overhead such as recurring launch mass. The production of oxygen from lunar materials is generally recognized as the highest priority process for lunar ISRU, for both human metabolic and fuel oxidation needs. The most challenging technology developments for future lunar settlements may lie in the extraction of elements (O, Fe, Mn, Ti, Si, etc) from local rocks and soils for life support, industrial feedstock and the production of propellants. With few exceptions (e.g., Johannson, 1992), nearly all technology development to date has employed an ap-proach based on inorganic chemistry (e.g. Allen et al., 1996). None of these technologies include concepts for inte-grating the ISRU system with a bioregenerative life support system and a food production systems. Bioregenerative life support efforts have recently been added to the Constellation ISRU development program (Sanders et al, 2007). Methods and Concerns: The European Micro-Ecological Life Support System Alternative (MELiSSA) is an ad-vanced concept for organizing a bioregenerative system for long term space flights and extraterrestrial settlements (Hendrickx, De Wever et al., 2005). However the MELiSSA system is a net consumer of ISRU products without a net return to in-situ technologies, e.g.. to extract elements as a result of complete closure of MELiSSA. On the other hand, the physical-chemical processes for ISRU are typically massive (relative to the rate of oxygen

  4. In situ synthesis and formation mechanism of ZrC and ZrB2 by combustion synthesis from the Co-Zr-B4C system

    Directory of Open Access Journals (Sweden)

    Mengxian Zhang

    2015-09-01

    Full Text Available ZrC-ZrB2-based composites were prepared by combustion synthesis (CS reaction from 10 wt.% to 50 wt.% Co-Zr-B4C powder mixtures. With increasing Co contents, the particle sizes of near-spherical ZrC and platelet-like ZrB2 decreased from 1 μm to 0.5 μm and from 5 μm to 2 μm, respectively. In addition, the formation mechanism of ZrC and ZrB2 was explored by the phase transition and microstructure evolution on the combustion wave quenched sample in combination with differential scanning calorimeter analysis. The results showed that the production of ZrC was ascribed to the solid-solid reaction between Zr and C and the precipitation from the Co-Zr-B-C melt, while ZrB2 was prepared from the saturated liquid. The low B concentration in the Co-Zr-B-C liquid and high cooling rate during the CS process led to the presence of Co2B and ZrCo3B2 in the composites. The addition of Co in the Co-Zr-B4C system not only prevented ZrC and ZrB2 particulates from growing, but also promoted the occurrence of ZrC-ZrB2-forming reaction.

  5. Constraining processes of landscape change with combined in situ cosmogenic 14C-10Be analysis

    Science.gov (United States)

    Hippe, Kristina

    2017-10-01

    Reconstructing Quaternary landscape evolution today frequently builds upon cosmogenic-nuclide surface exposure dating. However, the study of complex surface exposure chronologies on the 102-104 years' timescale remains challenging with the commonly used long-lived radionuclides (10Be, 26Al, 36Cl). In glacial settings, key points are the inheritance of nuclides accumulated in a rock surface during a previous exposure episode and (partial) shielding of a rock surface after the main deglaciation event, e.g. during phases of glacier readvance. Combining the short-lived in situ cosmogenic 14C isotope with 10Be dating provides a valuable approach to resolve and quantify complex exposure histories and burial episodes within Lateglacial and Holocene timescales. The first studies applying the in situ14C-10Be pair have demonstrated the great benefit from in situ14C analysis for unravelling complex glacier chronologies in various glacial environments worldwide. Moreover, emerging research on in situ14C in sedimentary systems highlights the capacity of combined in situ14C-10Be analysis to quantify sediment transfer times in fluvial catchments or to constrain changes in surface erosion rates. Nevertheless, further methodological advances are needed to obtain truly routine and widely available in situ14C analysis. Future development in analytical techniques has to focus on improving the analytical reproducibility, reducing the background level and determining more accurate muonic production rates. These improvements should allow extending the field of applications for combined in situ14C-10Be analysis in Earth surface sciences and open up a number of promising applications for dating young sedimentary deposits and the quantification of recent changes in surface erosion dynamics.

  6. Process simulation of oxy-combustion for maximization of energy output using ASPEN plus

    Directory of Open Access Journals (Sweden)

    Subhodeep Banerjee, Xiao Zhang, Suraj K. Puvvada, Ramesh K. Agarwal

    2014-01-01

    Full Text Available Oxy-fuel combustion is a next-generation combustion technology that shows promise to address the need of low-cost carbon capture from fossil fueled power plants. Oxy-fuel combustion requires expensive pre-processing in an air separation unit to separate pure oxygen from air for the combustion process, which reduces the overall efficiency of the process. This paper employs ASPEN Plus process simulation software to model a simple oxy-fuel combustor and investigates the effect of various parameters on the energy output. The composition of the flue gas is carefully examined. The results of this study provide a starting point for optimized oxy-fuel combustion operation for maximum energy output, which will be crucial for future deployment of oxy-fuel combustion technology.

  7. Effect of ash content on the combustion process of simulated MSW in the fixed bed.

    Science.gov (United States)

    Sun, Rui; Ismail, Tamer M; Ren, Xiaohan; Abd El-Salam, M

    2016-02-01

    This paper experimentally and numerically investigates the effects of ash content on the combustion process of simulated Municipal Solid Waste (MSW). A fixed-bed experimental reactor was utilized to reveal the combustion characteristics. Temperature distributions, ignition front velocity, and the characteristics of gas species' release were measured and simulated during the combustion process. In the present work, the two-dimensional unsteady mathematical heterogeneous model was developed to simulate the combustion process in the bed, including the process rate model as well as NOx production model. The simulation results in the bed are accordant with the experimental results. The results show that as ash content increases, the lower burning rate of fuel results in char particles leaving the grate without being fully burned, causing a loss of combustible material in the MSW in a fixed bed and therefore reducing the combustion efficiency and increasing the burning time of the MSW. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. A summary report on combustion and gasification processes

    Energy Technology Data Exchange (ETDEWEB)

    Rath, L.K.; Lee, G.T.

    1996-08-01

    Six poster papers regarding combustion and gasification were reviewed. These six papers address various different technology subjects: (1) underground coal gasification modeling, (2) wood gasification kinetics, (3) heat transfer surface pretreatment by iron implantation, (4) coal water slurry stabilization technology, (5) coal log pipeline technology, and (6) nuclear reactor decontamination. Summaries and comments of the following papers are presented: Characterization of Flow and Chemical Processes in an Underground Gasifier at Great Depth; Model for Reaction Kinetics in Pyrolysis of Wood; Development of a Stainless Steel Heat Transfer Surface with Low Scaling Tendency; Storage and Transportation of Coal Water Mixtures; Coal Log Pipeline: Development Status of the First Commercial System; and Decontamination of Nuclear Systems at the Grand Gulf Nuclear Station.

  9. Influence of Process Parameters on Coal Combustion Performance

    DEFF Research Database (Denmark)

    Lans, Robert Pieter Van Der

    The objective of this study is to improve the understanding of nitrogen oxide formation and carbon burnout during the combustion of pulverized coal, and to contribute to addressing the potential of chemical engineering models for the prediction of furnace temperatures, NO emissions and the amount...... study has been performed in order to initiate an investigation of the potential of chemical engineering models to predict NO from pulverized fuel burners. The success of chemical engineering modeling is strongly connected to the simplification of the flow pattern into a reactor configuration...... and swirl number on the flow pattern in the near burner zone of the laboratory furnace-model were studied. Experimentally obtained residence time distributions have been used to derive a chemical reaction engineering model for the mixing process. The model is based on a combination of plug flow reactors...

  10. A Facile in Situ and UV Printing Process for Bioinspired Self-Cleaning Surfaces

    Directory of Open Access Journals (Sweden)

    Marina A. González Lazo

    2016-08-01

    Full Text Available A facile in situ and UV printing process was demonstrated to create self-cleaning synthetic replica of natural petals and leaves. The process relied on the spontaneous migration of a fluorinated acrylate surfactant (PFUA within a low-shrinkage acrylated hyperbranched polymer (HBP and its chemical immobilization at the polymer-air interface. Dilute concentrations of 1 wt. % PFUA saturated the polymer-air interface within 30 min, leading to a ten-fold increase of fluorine concentration at the surface compared with the initial bulk concentration and a water contact angle (WCA of 108°. A 200 ms flash of UV light was used to chemically crosslink the PFUA at the HBP surface prior to UV printing with a polydimethylsiloxane (PDMS negative template of red and yellow rose petals and lotus leaves. This flash immobilization hindered the reverse migration of PFUA within the bulk HBP upon contacting the PDMS template, and enabled to produce texturized surfaces with WCA well above 108°. The synthetic red rose petal was hydrophobic (WCA of 125° and exhibited the adhesive petal effect. It was not superhydrophobic due to insufficient concentration of fluorine at its surface, a result of the very large increase of the surface of the printed texture. The synthetic yellow rose petal was quasi-superhydrophobic (WCA of 143°, roll-off angle of 10° and its self-cleaning ability was not good also due to lack of fluorine. The synthetic lotus leaf did not accurately replicate the intricate nanotubular crystal structures of the plant. In spite of this, the fluorine concentration at the surface was high enough and the leaf was superhydrophobic (WCA of 151°, roll-off angle below 5° and also featured self-cleaning properties.

  11. In-Situ Statistical Analysis of Autotune Simulation Data using Graphical Processing Units

    Energy Technology Data Exchange (ETDEWEB)

    Ranjan, Niloo [ORNL; Sanyal, Jibonananda [ORNL; New, Joshua Ryan [ORNL

    2013-08-01

    Developing accurate building energy simulation models to assist energy efficiency at speed and scale is one of the research goals of the Whole-Building and Community Integration group, which is a part of Building Technologies Research and Integration Center (BTRIC) at Oak Ridge National Laboratory (ORNL). The aim of the Autotune project is to speed up the automated calibration of building energy models to match measured utility or sensor data. The workflow of this project takes input parameters and runs EnergyPlus simulations on Oak Ridge Leadership Computing Facility s (OLCF) computing resources such as Titan, the world s second fastest supercomputer. Multiple simulations run in parallel on nodes having 16 processors each and a Graphics Processing Unit (GPU). Each node produces a 5.7 GB output file comprising 256 files from 64 simulations. Four types of output data covering monthly, daily, hourly, and 15-minute time steps for each annual simulation is produced. A total of 270TB+ of data has been produced. In this project, the simulation data is statistically analyzed in-situ using GPUs while annual simulations are being computed on the traditional processors. Titan, with its recent addition of 18,688 Compute Unified Device Architecture (CUDA) capable NVIDIA GPUs, has greatly extended its capability for massively parallel data processing. CUDA is used along with C/MPI to calculate statistical metrics such as sum, mean, variance, and standard deviation leveraging GPU acceleration. The workflow developed in this project produces statistical summaries of the data which reduces by multiple orders of magnitude the time and amount of data that needs to be stored. These statistical capabilities are anticipated to be useful for sensitivity analysis of EnergyPlus simulations.

  12. Self-sustaining smoldering combustion for NAPL remediation: laboratory evaluation of process sensitivity to key parameters.

    Science.gov (United States)

    Pironi, Paolo; Switzer, Christine; Gerhard, Jason I; Rein, Guillermo; Torero, Jose L

    2011-04-01

    -scale lower bounds on concentration and air flux and upper bound on grain size were not achieved; larger scale experiments and field trials where lateral heat losses are much less significant are necessary to define these process limits for the purposes of field application. This work provides valuable design data for pilot field trials of both in situ and ex situ smoldering remediation applications.

  13. Rheology in Processing of in Situ Composites of Polypropylene and Low Melting Poing Metals

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The low melting point metallic tin powder or alloy of tin and lead was blended with polypropylene. A kind of in situ composite has been prepared.The variations of torque were studied when the composites were mixed in Haake torque rheogeniometer. By way of capillary extrusion, effects upon rheology of the in situ composites of the low melting point metals (LMPM) and coupling agent for their different variety and content,were investigated. From flow curves, the results indicate that in situ composites mixed with the LMPM are a kind of pseudoplastic fluid. If the LMPM were melted,the higher the content of the LMPM, the lower apparent viscosity of composites.Meanwhile,when the coupling agent is added into composites,the viscosity of composite will go up first and drop then. This shows that the LMPM have a promoter flow action on the polypropylene.

  14. In situ preparation of hydrophobic CaCO3 nanoparticles in a gas-liquid microdispersion process

    Institute of Scientific and Technical Information of China (English)

    Le Du; Yujun Wang; Guangsheng Luo

    2013-01-01

    This study presents a novel process of in situ surface modification of CaCO3 nanoparticles using a multipleorifice dispersion microreactor.CO2/Ca(OH)2 precipitation reaction was employed to prepare CaCO3 nanoparticles with sodium stearate surfactant.Synthesized CaCO3 products were characterized by thermogravimetric analysis (TGA),infra-red (IR),X-ray diffraction (XRD),transmission electron microscopy (TEM) and Brunauer-Emmet-Teller analysis (BET).The effect of various operation parameters on nanopartides and the dosage of sodium stearate were determined.The results showed that the preparation process could be precisely controlled with efficient mass transfer process.The particles were highly hydrophobic with a contact angle of 117° and monodisperse with an average size of 30 nm.The adsorptions of sodium stearate and calcium ion on solid particles during the in situ surface modification process were investigated.

  15. Novel Salt-Assisted Combustion Synthesis of High Surface Area Ceria Nanopowders by An Ethylene Glycol-Nitrate Combustion Process

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A novel salt-assisted combustion process with ethylene glycol as a fuel and nitrate as an oxidant to synthesize high surface area ceria nanopowders was reported. The effects of various tunable conditions, such as fuel-to-oxidant ratio, type of salts, and amount of added salts, on the characteristics of the as-prepared powders were investigated by X-ray diffraction, transmission electron microscopy and BET surface area measurement. A mechanism scheme was proposed to illustrate the possible formation processes of well-dispersed ceria nanoparticles in the salt-assisted combustion synthesis. It was verified that the simple introduction of leachable inert inorganic salts as an excellent agglomeration inhibitor into the redox mixture precursor leads to the formation of well-dispersed ceria particles with particle size in the range of 4~6 nm and a drastic increase in the surface area. The presence of KCl results in an over ten-fold increment in specific surface area from 14.10 m2·g-1 for the produced ceria powders via the conventional combustion synthesis process to 156.74 m2·g-1 for the product by the salt-assisted combustion synthesis process at the same molar ratio of ethylene glycol-nitrate.

  16. Electrochemical Processes for In-Situ Treatment of Contaminated Soils - Final Report - 09/15/1996 - 01/31/2001

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Chin-Pao

    2001-05-31

    This project will study electrochemical processes for the in situ treatment of soils contaminated by mixed wastes, i.e., organic and inorganic. Soil samples collected form selected DOE waste sites will be characterized for specific organic and metal contaminants and hydraulic permeability. The soil samples are then subject to desorption experiments under various physical-chemical conditions such as pH and the presence of surfactants. Batch electro-osmosis experiments will be conducted to study the transport of contaminants in the soil-water systems. Organic contaminants that are released from the soil substrate will be treated by an advanced oxidation process, i.e., electron-Fantan. Finally, laboratory reactor integrating the elector-osmosis and elector-Fantan processes will be used to study the treatment of contaminated soil in situ.

  17. Guidelines for process development and future cost reduction of CO 2 post-combustion capture

    NARCIS (Netherlands)

    Abu-Zahra, M.R.M.; Fernandez, E.S.; Goetheer, E.L.V.

    2011-01-01

    In this work, a perspective is given on the development lines for CO 2 post-combustion capture technology. Guidelines for cost reductions and suggestions for future research on solvent and process development are presented. By analyzing the post-combustion capture process in this work, it is evident

  18. Combustion process for synthesis of carbon nanomaterials from liquid hydrocarbon

    Science.gov (United States)

    Diener, Michael D.; Alford, J. Michael; Nabity, James; Hitch, Bradley D.

    2007-01-02

    The present invention provides a combustion apparatus for the production of carbon nanomaterials including fullerenes and fullerenic soot. Most generally the combustion apparatus comprises one or more inlets for introducing an oxygen-containing gas and a hydrocarbon fuel gas in the combustion system such that a flame can be established from the mixed gases, a droplet delivery apparatus for introducing droplets of a liquid hydrocarbon feedstock into the flame, and a collector apparatus for collecting condensable products containing carbon nanomaterials that are generated in the combustion system. The combustion system optionally has a reaction zone downstream of the flame. If this reaction zone is present the hydrocarbon feedstock can be introduced into the flame, the reaction zone or both.

  19. In-situ transmission measurements as process control for thin-film silicon solar cells

    NARCIS (Netherlands)

    Meier, M.; Muthmann, S.; Flikweert, A. J.; Dingemans, G.; M. C. M. van de Sanden,; Gordijn, A.

    2011-01-01

    In this work, in-situ transmission measurements using plasma as light source are presented for the determination of growth rate and crystallinity during silicon thin-film growth. The intensity of distinct plasma emission lines was measured at the backside of the transparent substrates on which silic

  20. In-situ Spectroscopic Studies and Modelling of Crystallization Processes of Sulphuric Acid Catalysts

    DEFF Research Database (Denmark)

    Oehlers, C.; Fehrmann, Rasmus; Masters, Stephen Grenville

    1996-01-01

    Deactivation of commercial and prototype sulphuric acid catalysts has been investigated in-situ by ESR spectroscopy. The influence of support pore structure,and the chemical composition of the catalyst and the gas phase was dicussed.A statistical lattice model was applied to describe...

  1. Formation of catalytically active gold-polymer microgel hybrids via a controlled in situ reductive process

    NARCIS (Netherlands)

    Agrawal, Garima; Schuerings, Marco Philipp; van Rijn, Patrick; Pich, Andrij

    2013-01-01

    A newly developed N-vinylcaprolactam/acetoacetoxyethyl methacrylate/acrylic acid based microgel displays in situ reductive reactivity towards HAuCl4, forming hybrid polymer-gold nanostructures at ambient temperature without additional reducing agents. The colloidal gold nanostructure is selectively

  2. Sintering process optimization for multi-layer CGO membranes by in situ techniques

    DEFF Research Database (Denmark)

    Kaiser, Andreas; Prasad, A.S.; Foghmoes, Søren Preben Vagn;

    2013-01-01

    The sintering of asymmetric CGO bi-layers (thin dense membrane on a porous support; Ce0.9Gd0.1O1.95-delta = CGO) with Co3O4 as sintering additive has been optimized by combination of two in situ techniques. Optical dilatometry revealed that bi-layer shape and microstructure are dramatically chang...

  3. Biodiesel production from rice bran by a two-step in-situ process.

    Science.gov (United States)

    Shiu, Pei-Jing; Gunawan, Setiyo; Hsieh, Wen-Hao; Kasim, Novy S; Ju, Yi-Hsu

    2010-02-01

    The production of fatty acid methyl esters (FAMEs) by a two-step in-situ transesterification from two kinds of rice bran was investigated in this study. The method included an in-situ acid-catalyzed esterification followed by an in-situ base-catalyzed transesterification. Free fatty acids (FFAs) level was reduced to less than 1% for both rice bran A (initial FFAs content=3%) and rice bran B (initial FFAs content=30%) in the first step under the following conditions: 10 g rice bran, methanol to rice bran ratio 15 mL/g, H(2)SO(4) to rice bran mass ratio 0.18, 60 degrees C reaction temperature, 600 rpm stirring rate, 15 min reaction time. The organic phase of the first step product was collected and subjected to a second step reaction by adding 8 mL of 5N NaOH solution and allowing to react for 60 and 30 min for rice bran A and rice bran B, respectively. FAMEs yields of 96.8% and 97.4% were obtained for rice bran A and rice bran B, respectively, after this two-step in-situ reaction.

  4. Microstructural evolution and strengthening behavior in in-situ magnesium matrix composites fabricated by solidification processing

    Energy Technology Data Exchange (ETDEWEB)

    Chelliah, Nagaraj M., E-mail: cmnraj.7@gmail.com [Department of Mechanical Engineering, Indian Institute of Technology Ropar, Rupnagar 140001, Punjab (India); Singh, Harpreet, E-mail: harpreetsingh@iitrpr.ac.in [Department of Mechanical Engineering, Indian Institute of Technology Ropar, Rupnagar 140001, Punjab (India); Surappa, M.K., E-mail: mirle@materials.iisc.ac.in [Department of Materials Engineering, Indian Institute of Science, Bengaluru 560012, Karnataka (India)

    2017-06-15

    In-situ magnesium matrix composites with three different matrix materials (including Mg, AZ91 and AE44 Mg-alloys) were fabricated by injecting cross-linked polymer directly into the molten Mg/Mg-alloys, and having it convert to the 2.5 vol% SiCNO ceramic phase using liquid stir-casting method. In-situ chemical reaction took place within the molten slurry tending to produce 42 and 18 vol% Mg{sub 2}Si crystals in Mg and AE44 matrix composites, respectively but not in AZ91 matrix composite. Microstructural evolution of Mg{sub 2}Si crystals was discussed on the basis of availability of heterogeneous nucleation sites and amount of Al-atoms in the molten slurry. The observed micro-hardness and yield strengths are enhanced by factor of four to three as compared to their unreinforced counterparts, and Taylor strengthening was found to be the predominant strengthening mechanism in magnesium and AE44 matrix composites. Summation model predicted the yield strengths of the fabricated composites more preciously when compared to Zhang and Chen, and modified Clyne models. - Highlights: • In-situ magnesium composites were fabricated using liquid stir-casting method. • In-situ pyrolysis of cross-linked polymer has been utilized to obtain ceramic phases. • Mg{sub 2}Si crystals were formed in magnesium and AE44 matrix composites but not in AZ91 matrix composites. • The variation in size and morphology of Mg{sub 2}Si crystals with matrix materials are discussed. • Strengthening mechanisms in in-situ composites are analyzed and discussed.

  5. Signal Processing Methods for Liquid Rocket Engine Combustion Stability Assessments

    Science.gov (United States)

    Kenny, R. Jeremy; Lee, Erik; Hulka, James R.; Casiano, Matthew

    2011-01-01

    The J2X Gas Generator engine design specifications include dynamic, spontaneous, and broadband combustion stability requirements. These requirements are verified empirically based high frequency chamber pressure measurements and analyses. Dynamic stability is determined with the dynamic pressure response due to an artificial perturbation of the combustion chamber pressure (bomb testing), and spontaneous and broadband stability are determined from the dynamic pressure responses during steady operation starting at specified power levels. J2X Workhorse Gas Generator testing included bomb tests with multiple hardware configurations and operating conditions, including a configuration used explicitly for engine verification test series. This work covers signal processing techniques developed at Marshall Space Flight Center (MSFC) to help assess engine design stability requirements. Dynamic stability assessments were performed following both the CPIA 655 guidelines and a MSFC in-house developed statistical-based approach. The statistical approach was developed to better verify when the dynamic pressure amplitudes corresponding to a particular frequency returned back to pre-bomb characteristics. This was accomplished by first determining the statistical characteristics of the pre-bomb dynamic levels. The pre-bomb statistical characterization provided 95% coverage bounds; these bounds were used as a quantitative measure to determine when the post-bomb signal returned to pre-bomb conditions. The time for post-bomb levels to acceptably return to pre-bomb levels was compared to the dominant frequency-dependent time recommended by CPIA 655. Results for multiple test configurations, including stable and unstable configurations, were reviewed. Spontaneous stability was assessed using two processes: 1) characterization of the ratio of the peak response amplitudes to the excited chamber acoustic mode amplitudes and 2) characterization of the variability of the peak response

  6. In-situ formation of complex oxide precipitates during processing of oxide dispersion strengthened ferritic steels

    Energy Technology Data Exchange (ETDEWEB)

    Jayasankar, K., E-mail: jayasankar.met@gmail.com [CSIR-Institute of Minerals & Materials Technology, Bhubaneswar 751013 (India); Pandey, Abhishek [CSIR-Advanced Materials & Processes Research Institute, Bhopal 462026 (India); Mishra, B.K. [CSIR-Institute of Minerals & Materials Technology, Bhubaneswar 751013 (India); Das, Siddhartha [Indian Institute of Technology, Kharagpur 721302 (India)

    2016-01-15

    Highlights: • Use of dual drive planetary ball mill for Bench scale (>1 kg) production. • X-ray diffraction and TEM were used to study transformations during sintering. • HIPped and rolled samples with nearly 99% density successfully produced. - Abstract: In fusion and fission reactor material development, ODS alloys are the most suitable candidate materials due to its high temperature creep properties and irradiation resistance properties. This paper describes the preparation of oxide dispersion strengthened alloy powder in large quantity (>1 kg batch) in dual drive planetary ball mill using pre-alloyed ferrtic steel powder with nano sized Y{sub 2}O{sub 3}. The consolidation of the powders was carried out in hot isostatic press (HIP) followed by hot rolling. 99% of the theoretical density was achieved by this method. The vickers hardness values of pressed and rolled samples were in the range of 380 ± 2HV and 719 ± 2HV, respectively. Samples were further investigated using X-ray diffraction particle size analyzer and electron microscope. Initial increase in particle size with milling was observed showing flattening of the particle. It was found that 5 h of milling time is sufficient to reduce the particle size to achieve the desired size. Transmission electron microscopy analysis of milled ODS steel powder revealed a uniform distribution of combustion synthesized nano-Y{sub 2}O{sub 3} in ferritic steel matrix after a milling time of 5 h. Preliminary results demonstrated suitability of dual drive planetary ball mill for mass production of alloy within a short time due to various kinds of forces acting at a time during milling process. Fine monoclinic Y{sub 2}Si{sub 2}O{sub 7} precipitates were also observed in the steel. This study explains the particle characteristics of nano Y{sub 2}O{sub 3} dispersed ODS powder and formation of nano clusters in ODS ferritic alloy.

  7. In-Situ Anaerobic Biosurfactant Production Process For Remediation Of DNAPL Contamination In Subsurface Aquifers

    Science.gov (United States)

    Albino, J. D.; Nambi, I. M.

    2009-12-01

    microbial cultures. The microorganisms responsible for biosurfactant production was isolated and identified as Pseudomonas Sp (designated as Pseudomonas Sp ANBIOSURF-1, Gene bank no: FJ930079), Pseudomonas stutzeri (MTCC 10033), Pseudomonas Sp (MTCC 10032) from groundwater, soil and municipal sewage sludge enrichments respectively. This study confirms that biosurfactants can be produced under anaerobic conditions and also in sufficient quantities. The cultures were also able to cometabolically degrade PCE to Ethylene. The isolated microorganisms can be used for remediation of DNAPL contaminated sites by in-situ biosurfactant production.

  8. Fuels for homogenous, self-igniting combustion processes; Brennstoffe fuer homogene selbstgezuendete Verbrennungsprozesse - Jahresbericht 2007

    Energy Technology Data Exchange (ETDEWEB)

    Escher, A.; Boulouchos, K.

    2007-07-01

    This annual report for the Swiss Federal Office of Energy (SFOE), reports on work done in 2007 at the Swiss Federal Institute of Technology ETH in Zurich, Switzerland, on fuels for homogenous, self-igniting combustion processes. A single-stroke engine was used to test the combustion of n-heptane, n-butane and their combinations. The flexibility of the test-bed is discussed and the combustion characteristics observed are described. Also, the results obtained are presented and discussed. Multi-zone simulation and factors influencing the combustion are examined. Ignition and combustion of synthetic, diesel-like fuels are discussed. Co-operation with the project started in 2007 by the Society for Research on Combustion Engines which involves other universities and several industrial companies is noted.

  9. Direct in situ observations of single Fe atom catalytic processes and anomalous diffusion at graphene edges

    Science.gov (United States)

    Zhao, Jiong; Deng, Qingming; Avdoshenko, Stanislav M.; Fu, Lei; Eckert, Jürgen; Rümmeli, Mark H.

    2014-01-01

    Single-atom catalysts are of great interest because of their high efficiency. In the case of chemically deposited sp2 carbon, the implementation of a single transition metal atom for growth can provide crucial insight into the formation mechanisms of graphene and carbon nanotubes. This knowledge is particularly important if we are to overcome fabrication difficulties in these materials and fully take advantage of their distinct band structures and physical properties. In this work, we present atomically resolved transmission EM in situ investigations of single Fe atoms at graphene edges. Our in situ observations show individual iron atoms diffusing along an edge either removing or adding carbon atoms (viz., catalytic action). The experimental observations of the catalytic behavior of a single Fe atom are in excellent agreement with supporting theoretical studies. In addition, the kinetics of Fe atoms at graphene edges are shown to exhibit anomalous diffusion, which again, is in agreement with our theoretical investigations. PMID:25331874

  10. Direct in situ observations of single Fe atom catalytic processes and anomalous diffusion at graphene edges.

    Science.gov (United States)

    Zhao, Jiong; Deng, Qingming; Avdoshenko, Stanislav M; Fu, Lei; Eckert, Jürgen; Rümmeli, Mark H

    2014-11-01

    Single-atom catalysts are of great interest because of their high efficiency. In the case of chemically deposited sp(2) carbon, the implementation of a single transition metal atom for growth can provide crucial insight into the formation mechanisms of graphene and carbon nanotubes. This knowledge is particularly important if we are to overcome fabrication difficulties in these materials and fully take advantage of their distinct band structures and physical properties. In this work, we present atomically resolved transmission EM in situ investigations of single Fe atoms at graphene edges. Our in situ observations show individual iron atoms diffusing along an edge either removing or adding carbon atoms (viz., catalytic action). The experimental observations of the catalytic behavior of a single Fe atom are in excellent agreement with supporting theoretical studies. In addition, the kinetics of Fe atoms at graphene edges are shown to exhibit anomalous diffusion, which again, is in agreement with our theoretical investigations.

  11. In-situ investigation of the calcination process of mixed oxide xerogels with Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Panitz, J.C. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    The controlled calcination of materials derived by sol-gel reactions is important for the evolution of the final structure. Raman spectroscopy is an ideal tool for the identification of surface species under in-situ conditions, as demonstrated in the following for the example of a molybdenum oxide-silica xerogel. Raman spectra of this particular sample were recorded at temperatures as high as 1173 K, and compared with those of a reference material.(author) 3 figs., 4 refs.

  12. Evolution of Submicrometer Organic Aerosols during a Complete Residential Coal Combustion Process.

    Science.gov (United States)

    Zhou, Wei; Jiang, Jingkun; Duan, Lei; Hao, Jiming

    2016-07-19

    In the absence of particulate matter (PM) control devices, residential coal combustion contributes significantly to ambient PM pollution. Characterizing PM emissions from residential coal combustion with high time resolution is beneficial for developing control policies and evaluating the environmental impact of PM. This study reports the evolution of submicrometer organic aerosols (OA) during a complete residential coal combustion process, that is, from fire start to fire extinction. Three commonly used coal types (bituminous, anthracite, and semicoke coals) were evaluated in a typical residential stove in China. For all three types of coal, the OA emission exhibited distinct characteristics in the four stages, that is, ignition, fierce combustion, relatively stable combustion, and ember combustion. OA emissions during the ignition stage accounted for 58.2-85.4% of the total OA emission of a complete combustion process. The OA concentration decreased rapidly during the fierce combustion stage and remained low during the relatively stable combustion stage. During these two stages, a significant ion peak of m/z 73 from organic acids were observed. The degree of oxidation of the OA increased from the first stage to the last stage. Implications for ambient OA source-apportionment and residential PM emission characterization and control are discussed.

  13. Digital signal processing of cylinder pressure data for combustion diagnostics of HCCI engine

    Science.gov (United States)

    Kumar Maurya, Rakesh; Pal, Dev Datt; Kumar Agarwal, Avinash

    2013-03-01

    Diagnosis of combustion is necessary for the estimation of the combustion quality, and control of combustion timing in advanced combustion concepts like HCCI. Combustion diagnostics is often performed using digital processing of pressure signals measured using piezoelectric sensor installed in the combustion chamber of the engine. Four-step pressure signal processing consisting of (i) absolute pressure correction, (ii) phasing w.r.t. crank angle, (iii) cycle averaging and (iv) smoothening is used to get cylinder pressure data from the engine experiments, which is further analyzed to get information about combustion characteristics. This study focuses on various aspect of signal processing (cycle averaging and smoothing) of in-cylinder pressure signal from a HCCI engine acquired using a piezoelectric pressure sensor. Experimental investigations are conducted on a HCCI combustion engine operating at different engine speed/load/air-fuel ratio conditions. The cylinder pressure history of 3000 consecutive engine cycles is acquired for analysis using piezoelectric pressure sensor. This study determines the optimum number of engine cycles to be acquired for reasonably good pressure signals based on standard deviation of in-cylinder pressure, rate of pressure rise and rate of heat release signals. Different signal smoothening methods (using various digital filters) are also analyzed and their results are compared. This study also presents effect of signal processing methods on pressure, pressure rise rate and rate of heat release curves at different engine operating conditions.

  14. Effects of aqueous effluents from in situ fossil fuel processing technologies on aquatic systems. Annual progress report

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, H.L.; Anderson, A.D.

    1977-12-01

    This is the first annual report issued under a project to evaluate the effects of aqueous effluents from in-situ fossil fuel processing technologies on aquatic biota. Briefly, the goals of the project are to: evaluate the toxicity of process water effluents on aquatic biota; recommend maximum exposure concentrations for process water constituents; and assist DOE in using project data and recommendations to design control technologies and to assess environmental impacts. The project objectives for Year 1 were pursued through the following five tasks: a literature review on process water constituents; toxicity studies on the effect of process waters and six process water constituents on aquatic biota; degradation rate studies on four to six process water constituents; bioaccumulation studies on four to six process water constituents; and recommendations on maximum exposure concentrations for process water constituents based on data from the project and from the literature. Progress toward completion of these goals is presented.

  15. Co-evaporation process study of Cu{sub 2}ZnSnSe{sub 4} thin films by in situ light scattering and in situ X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Hartnauer, Stefan; Waegele, Leonard A.; Kaune, Gunar; Scheer, Roland [Photovoltaics Group, Martin-Luther-University Halle-Wittenberg, Halle (Saale) (Germany); Syrowatka, Frank [Martin-Luther-University Halle-Wittenberg, IZM/Nanotechnikum Weinberg, Halle (Saale) (Germany)

    2015-02-01

    Multi-stage co-evaporation processes for the growth of Cu{sub 2}ZnSnSe{sub 4} (CZTSe) thin films are investigated with time-resolved in situ angle-dispersive X-ray diffraction (in situ XRD). Different preparation protocols were applied and controlled by in situ laser light scattering (in situ LLS). The composition of the deposited layers was adjusted by making use of a stoichiometric transitions in the LLS signal at the point where the Cu content equals the [Zn + Sn]. The ability of in situ XRD to distinguish between CZTSe and ZnSe is used to develop new processes that minimize the formation of ZnSe as a secondary phase. At high temperatures, an initially grown ZnSe layer forms at the Mo interface, which may not be incorporated into the CZTSe due to Zn-rich preparation conditions. By using lower temperatures at the beginning, CZTSe growth starts directly and a heating step restores the high temperature of the substrate. Thus, the formation of secondary phases is diminished without losing the benefits of higher preparation temperature. The ZnSe growth is reduced and the formation of a continuous layer is not observed. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. Numerical study on the combustion process of a biogas spark-ignition engine

    Directory of Open Access Journals (Sweden)

    Carrera José L.

    2013-01-01

    Full Text Available The fuel called biogas is obtained through anaerobic digestion of different types of organic waste, providing a way to tap the energy stored in organic matter. The use of this fuel is also attractive from the standpoint of global warming because its application does not register a net emission of carbon dioxide into the atmosphere. One possible use for this fuel is to feed the spark-ignition internal combustion engines. In the present, there is little information available about the process of combustion in internal combustion engines fueled by biogas. The combustion process of an internal combustion engine ignition powered by biogas is characterized in terms of the duration of combustion, i.e., depending on the time elapsed while the reactants (methane and oxygen are transformed into products (mainly carbon dioxide and water. This study numerically evaluates the way in which the geometrical parameters such as the compression ratio and operating parameters like engine speed, the excess air, the time of spark timing and carbon dioxide content of biogas affect the evolution of the combustion process. To carry out this study, a five factors and two levels experiment was designed and conducted, based on which, the most influential parameters were identified. Equations expressing the combustion characteristic parameters, as a function of the geometric and operation parameters of a spark ignited engines, are delivered as a result.

  17. A stochastic model for the indicated pressure process and the dynamics of the internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Rizzoni, G. (Michigan Univ., Ann Arbor, MI (USA). Dept. of Electrical Engineering and Computer Science)

    1989-08-01

    In-cylinder gas pressure has long been recognized as a fundamental measure of performance in the internal combustion engine. Among the issues that have been the subject of research in recent years is the study of the effects cyclic combustion variability has on the cycle-to-cycle and cylinder-to-cylinder fluctuations in combustion pressures. Some of the research problems pertaining to cyclic combustion variability are to reformulate from a perspective markedly different from the fluid dynamic and thermodynamic models which traditionally characterize this research: a system viewpoint is embraced to construct a stochastic model for the indicated pressure process and the dynamics of the internal combustion engine. First a deterministic model for the dynamics of the engine is described; then a stochastic model is proposed for the cylinder pressure process. The deterministic model and the stochastic representation are then tied together in a Kalman filter model. Experimental results are discussed to validate the models.

  18. Mutagenicity assessment of aerosols in emissions from domestic combustion processes.

    Science.gov (United States)

    Canha, Nuno; Lopes, Isabel; Vicente, Estela Domingos; Vicente, Ana M; Bandowe, Benjamin A Musa; Almeida, Susana Marta; Alves, Célia A

    2016-06-01

    Domestic biofuel combustion is one of the major sources of regional and local air pollution, mainly regarding particulate matter and organic compounds, during winter periods. Mutagenic and carcinogenic activity potentials of the ambient particulate matter have been associated with the fraction of polycyclic aromatic hydrocarbons (PAH) and their oxygenated (OPAH) and nitrogenated (NPAH) derivatives. This study aimed at assessing the mutagenicity potential of the fraction of this polycyclic aromatic compound in particles (PM10) from domestic combustion by using the Ames assays with Salmonella typhimurium TA98 and TA100. Seven biofuels, including four types of pellets and three agro-fuels (olive pit, almond shell and shell of pine nuts), were tested in an automatic pellet stove, and two types of wood (Pinus pinaster, maritime pine, and Eucalyptus globulus, eucalypt) were burned in a traditional wood stove. For this latter appliance, two combustion phases-devolatilisation and flaming/smouldering-were characterised separately. A direct-acting mutagenic effect for the devolatilisation phase of pine combustion and for both phases of eucalypt combustion was found. Almond shell revealed a weak direct-acting mutagenic effect, while one type of pellets, made of recycled wastes, and pine (devolatilisation) presented a cytotoxic effect towards strain TA100. Compared to the manually fired appliance, the automatic pellet stove promoted lower polyaromatic mutagenic emissions. For this device, only two of the studied biofuels presented a weak mutagenic or cytotoxic potential.

  19. In Situ Observation of Initial Rusting Process of Steel Containing Al Using Synchrotron Radiation X-Rays

    Energy Technology Data Exchange (ETDEWEB)

    Morimoto, J.; Yamashita, M.; Uchida, H. [University of Hyogo, Hyogo (Japan); Doi, T.; Kamimura, T.; Miyuki, H. [Sumitomo Metal Industries, Ltd., Hyogo (Japan); Konishi, H.; Mizuki, J. [Japan Atomic Energy Agency, Hyogo (Japan)

    2008-04-15

    We observed initial rusting process of steel containing Al under wet/dry cyclic condition with NaCl solution film using in situ X-ray diffraction spectroscopy at Spring-8 synchrotron radiation facility. It was found that mass fraction of iron oxides such as {alpha}-FeOOH, {beta}-FeOOH and {gamma}-FeOOH varied with Al content. Some kinds of Al oxides wee also found at the initial stage of corrosion. Those corrosion products might affect the corrosion process and corrosion rate of the steel.

  20. Studies of ferroelectric heterostructure thin films, interfaces, and device-related processes via in situ analytical techniques.

    Energy Technology Data Exchange (ETDEWEB)

    Aggarwal, S.; Auciello, O.; Dhote, A. M.; Gao, Y.; Gruen, D. M.; Im, J.; Irene, E. A.; Krauss, A. R.; Muller, A. H.; Ramesh, R.

    1999-06-29

    The science and technology of ferroelectric thin films has experienced an explosive development during the last ten years. Low-density non-volatile ferroelectric random access memories (NVFRAMS) are now incorporated in commercial products such as ''smart cards'', while high permittivity capacitors are incorporated in cellular phones. However, substantial work is still needed to develop materials integration strategies for high-density memories. We have demonstrated that the implementation of complementary in situ characterization techniques is critical to understand film growth and device processes relevant to device development. We are using uniquely integrated time of flight ion scattering and recoil spectroscopy (TOF-ISARS) and spectroscopic ellipsometry (SE) techniques to perform in situ, real-time studies of film growth processes in the high background gas pressure required to growth ferroelectric thin films. TOF-ISARS provides information on surface processes, while SE permits the investigation of buried interfaces as they are being formed. Recent studies on SrBi{sub 2}Ta{sub 2}O{sub 9} (SBT) and Ba{sub x}Sr{sub 1{minus}x}TiO{sub 3} (BST) film growth and interface processes are discussed. Direct imaging of ferroelectric domains under applied electric fields can provide valuable information to understand domain dynamics in ferroelectric films. We discuss results of piezoresponse scanning force microscopy (SFM) imaging for nanoscale studies of polarization reversal and retention loss in Pb(Zr{sub x}Ti{sub 1{minus}x})O{sub 3} (PZT)-based capacitors. Another powerful technique suitable for in situ, real-time characterization of film growth processes and ferroelectric film-based device operation is based on synchrotrons X-ray scattering, which is currently being implemented at Argonne National Laboratory.

  1. In situ monitoring of a flash light sintering process using silver nano-ink for producing flexible electronics

    Science.gov (United States)

    Chung, Wan-Ho; Hwang, Hyun-Jun; Lee, Seung-Hyun; Kim, Hak-Sung

    2013-01-01

    In this work, a flash light sintering process using silver nano-inks is investigated. A silver nano-ink pattern was printed on a flexible PET (polyethylene terephthalate) substrate using a gravure-offset printing system. The printed silver nano-ink was sintered at room temperature and under ambient conditions using a flash of light from a xenon lamp using an in-house flash light sintering system. In order to monitor the light sintering process, a Wheatstone bridge electrical circuit was devised and changes in the voltage difference of the silver nano-ink were recorded during the sintering process using an oscilloscope. The sheet resistance changes during the sintering process were monitored using the in situ monitoring system devised, under various light conditions (e.g. light energy, on-time and off-time duration, and pulse numbers). The microstructure of the sintered silver film and the interface between the silver film and the PET substrate were observed using a scanning electron microscope, a focused ion beam and an optical microscope. The electrical sheet resistances of the sintered silver films were measured using a four-point probe method. Using the in situ monitoring system devised, the flash light sintering mechanism was studied for each type of light pulse (e.g. evaporation of organic binder followed by the forming of a neck-like junction and its growth, etc). The optimal flash light sintering condition is suggested on the basis of the in situ monitoring results. The optimized flash light sintering process produces a silver film with a lower sheet resistance (0.95 Ω/sq) compared with that of the thermally sintered silver film (2.03 Ω/sq) without damaging the PET substrate or allowing interfacial delamination between the silver film and the PET substrate.

  2. Laser processing of in situ TiN/Ti composite coating on titanium.

    Science.gov (United States)

    Sahasrabudhe, Himanshu; Soderlind, Julie; Bandyopadhyay, Amit

    2016-01-01

    Laser remelting of commercially pure titanium (CP-Ti) surface was done in a nitrogen rich inert atmosphere to form in situ TiN/Ti composite coating. Laser surface remelting was performed at two different laser powers of 425 W and 475 W. At each power, samples were fabricated with one or two laser scans. The resultant material was a nitride rich in situ coating that was created on the surface. The cross sections revealed a graded microstructure. There was presence of nitride rich dendrites dispersed in α-Ti matrix at the uppermost region. The structure gradually changed with lesser dendrites and more heat affected α-Ti phase maintaining a smooth interface. With increasing laser power, the dendrites appeared to be larger in size. Samples with two laser scans showed discontinuous dendrites and more α-Ti phase as compared to the samples with one laser scan. The resultant composite of TiN along with Ti2N in α-Ti showed substantially higher hardness and wear resistance than the untreated CP-Ti substrate. Coefficient of friction was also found to reduce due to surface nitridation. Leaching of Ti(4+) ions during wear test in DI water medium was found to reduce due to laser surface nitriding.

  3. Advanced diagnostics in oxy-fuel combustion processes

    Energy Technology Data Exchange (ETDEWEB)

    Brix, J.; Clausen, Soennik; Degn Jensen, A. (Technical Univ. of Denmark. CHEC Research Centre, Kgs. Lyngby (Denmark)); Boeg Toftegaard, M. (DONG Energy Power, Hvidovre (Denmark))

    2012-07-01

    This report sums up the findings in PSO-project 010069, ''Advanced Diagnostics in Oxy-Fuel Combustion Processes''. Three areas of optic diagnostics are covered in this work: - FTIR measurements in a 30 kW swirl burner. - IR measurements in a 30 kW swirl burner. - IR measurements in a laboratory scale fixed bed reactor. The results obtained in the swirl burner have proved the FTIR method as a valuable technique for gas phase temperature measurements. When its efficacy is evaluated against traditional thermocouple measurements, two cases, with and without probe beam stop, must however be treated separately. When the FTIR probe is operated with the purpose of gas phase concentration measurements the probe needs to operate with a beam stop mounted in front of it. With this beam stop in place it was shown that the measured gas phase temperature was affected by cooling, induced by the cooled beam stop. Hence, for a more accurate determination of gas phase temperatures the probe needed to operate without the beam stop. When this was the case, the FTIR probe showed superior to traditional temperature measurements using a thermocouple as it could measure the fast temperature fluctuations. With the beam stop in place the efficacy of the FTIR probe for gas temperature determination was comparable to the use of a traditional thermocouple. The evaluation of the FTIR technique regarding estimation of gas phase concentrations of H{sub 2}O, CO{sub 2} and CO showed that the method is reliable though it cannot be stated as particularly accurate. The accuracy of the method is dependent on the similarity of the reference emission spectra of the gases with those obtained in the experiments, as the transmittance intensity is not a linear function of concentration. The length of the optical path also affects the steadiness of the measurements. The length of the optical path is difficult to adjust on the small scales that are the focus of this work. However

  4. Reserch process geomigration during underground gasification and coal combustion

    Directory of Open Access Journals (Sweden)

    Zholudyev S.V.

    2014-12-01

    Full Text Available The chemical composition of subsoil water in the over- and subcoal deposits during underground combustion of brown coal can vary under coals thermal development product and pollution. Analysis of the substances-contaminants migratory in water is one of the main issues of further implementation of technologies UCG and UCC.

  5. Impedance matching of a coaxial antenna for microwave in-situ processing of polluted soils.

    Science.gov (United States)

    Pauli, Mario; Kayser, Thorsten; Wiesbeck, Werner; Komarov, Vyacheslav

    2011-01-01

    The present paper is focused on the minimization of return loss of a slotted coaxial radiator proposed for a decontamination system for soils contaminated by volatile or semi-volatile organic compounds such as oils or fuels. The antenna upgrade is achieved by coating it with a 5 mm thick Teflon layer. The electromagnetic characteristics reflection coefficient and power density distribution around the antenna surrounded by soils with different moisture levels are analyzed numerically. Simplified analytical approaches are employed to accelerate the optimization of the given antenna for microwave heating systems. The improved antenna design shows a good matching of the antenna to the surrounding soil with varying moisture levels. This ensures a high efficiency of the proposed in-situ soil decontamination system.

  6. Experimental Study on Dimethyl Ether Combustion Process in Homogeneous Charge Compression Ignition Mode

    Institute of Scientific and Technical Information of China (English)

    郑尊清; 史春涛; 尧命发

    2004-01-01

    Experimental study on homogeneous charge compression ignition (HCCI) combustion process was carried out on a single-cylinder direct injection diesel engine fueled with dimethyl ether(DME). The influence of inert gas CO2 on the ignition and combustion process was investigated. The research results indicate that because of the high cetane number of DME, the stable HCCI operating range is quite narrow while the engine has a high compression ratio. The HCCI operating range can be largely extended when the inert gas is inducted into the charging air. HCCI combustion of DME presents remarkable characteristic of two-stage combustion process. As the concentration of inert gas increases, the ignition timing of the first combustion stage delays, the peak heat release rate decreases, and the combustion duration extends. Inducting inert gas into charging air cannot make the combustion and heat release of DME occur at a perfect crank angle position. Therefore,to obtain HCCI operation for the fuel with high cetane number,other methods such as reducing engine compression ratio should be adopted. Emission results show that under HCCI operation, a nearly zero NOx emission can be obtained with no smoke emissions. But the HC and CO emissions are high, and both rise with the increase of the concentration of inert gases.

  7. Assessing microbial processes in deep-sea hydrothermal systems by incubation at in situ temperature and pressure

    Science.gov (United States)

    McNichol, Jesse; Sylva, Sean P.; Thomas, François; Taylor, Craig D.; Sievert, Stefan M.; Seewald, Jeffrey S.

    2016-09-01

    At deep-sea hydrothermal vents, a large source of potential chemical energy is created when reducing vent fluid and oxidizing seawater mix. In this environment, chemolithoautotrophic microbes catalyze exergonic redox reactions which in turn provide the energy needed to fuel their growth and the fixation of CO2 into biomass. In addition to producing new organic matter, this process also consumes compounds contained both in vent fluid and entrained seawater (e.g. H2, NO3-). Despite their biogeochemical importance, such reactions have remained difficult to quantify due to methodological limitations. To address this knowledge gap, this study reports a novel application of isobaric gas-tight fluid samplers for conducting incubations of hydrothermal vent fluids at in situ temperature and pressure. Eighteen 24 h incubations were carried out, representing seven distinct conditions that examine amendments consisting of different electron donors and acceptors. Microbial activity was observed in all treatments, and time series chemical measurements showed that activity was limited by electron acceptor supply, confirming predictions based on geochemical data. Also consistent with these predictions, the presence of nitrate increased rates of hydrogen consumption and yielded ammonium as a product of nitrate respiration. The stoichiometry of predicted redox reactions was also determined, revealing that the sulfur and nitrogen cycles are incompletely understood at deep-sea vents, and likely involve unknown intermediate redox species. Finally, the measured rates of redox processes were either equal to or far greater than what has been reported in previous studies where in situ conditions were not maintained. In addition to providing insights into deep-sea hydrothermal vent biogeochemistry, the methods described herein also offer a practical approach for the incubation of any deep-sea pelagic sample under in situ conditions.

  8. Combustion Technology for Incinerating Wastes from Air Force Industrial Processes.

    Science.gov (United States)

    1984-02-01

    waste for energy (not recycling cement kiln dust for clinker ) to be distinguishable from a commercial hazardous waste incinerator in -" its potential...ORGANIZATION NAME AND ADDRESS 10 PROGRAM ELEMENT . PROJECT, TASK . National Bureau of Standards AREA & WORK UNIT NUMBERS Washington D.C. 20234 PE 63723F JON...high temperature combustion zone transit time which significantly exceeds fuel droplet burnout and mixing times, and (4) employing afterburners

  9. Method and system for the removal of oxides of nitrogen and sulfur from combustion processes

    Science.gov (United States)

    Walsh, John V.

    1987-12-15

    A process for removing oxide contaminants from combustion gas, and employing a solid electrolyte reactor, includes: (a) flowing the combustion gas into a zone containing a solid electrolyte and applying a voltage and at elevated temperature to thereby separate oxygen via the solid electrolyte, (b) removing oxygen from that zone in a first stream and removing hot effluent gas from that zone in a second stream, the effluent gas containing contaminant, (c) and pre-heating the combustion gas flowing to that zone by passing it in heat exchange relation with the hot effluent gas.

  10. Characterization of degeneration process in thermo-acoustic combustion instability using dynamical systems theory

    Science.gov (United States)

    Hayashi, Kenta; Gotoda, Hiroshi; Okuno, Yuta; Tachibana, Shigeru; Tokyo University of Science Collaboration; Japan Aerospace Exploration Agency Collaboration

    2015-11-01

    We have experimentally investigated the degeneration process of combustion instability in a lean premixed gas-turbine model combustor on the basis of dynamical systems theory. Our previous study reported that with increasing the equivalence ratio, the dynamical behavior of combustion state close to lean blowout transits from stochastic fluctuations to periodic thermoacoustic combustion oscillations via low-dimensional chaotic oscillations. The further increase in the equivalence ratio gives rise to the quasi-periodic oscillations and the subsequent chaotic oscillations with small amplitudes. The route to chaotic oscillations is quantitatively shown by the use of nonlinear time series analysis involving the color recurrence plots, permutation entropy and local predictor.

  11. EMPLOYING OPTICAL MEASUREMENTS FOR MONITORING AND DIAGNOSTICS OF COMBUSTION PROCESS IN INDUSTRIAL CONDITIONS

    Directory of Open Access Journals (Sweden)

    Waldemar Wójcik

    2017-01-01

    Full Text Available The paper discusses some practical problems conected with introdction of modern coal combustion technologies as well as biomass co-combustion. In order to ensure that the combustion process runs in a proper way, the multichannel fiber optic monitoring system was applied. The system converts the optical signals coming from several flame zones to electrical that were further transmitted to the control room. The article prsents signal analyses made in time-frequency domain using short-time Fourier transform and wavelet transform and the way of their visualization to power boiler operators

  12. In situ study of key material and process reliability issues in the chemical vapor deposition of copper

    Science.gov (United States)

    Lou, Ishing

    With the limitations of current aluminum based metallization schemes used in microelectronics, the development of a manufacturable chemical vapor deposition (CVD) process for copper metallization schemes is crucial to meet the stringent requirements of sub-quarter micron device technology and beyond. The work presented herein focused on investigating key material and process reliability issues pertaining to Cu CVD processing. In particular, a unique combination of in-situ gas phase Fourier transform infrared (FTIR) and quadrupole mass spectrometry (QMS) was employed to study the role of hydrogen in thermal CVD of copper using (tmvs)Cusp{I}(hfac). These studies showed that hydrogen provides significant enhancement in the deposition rate of copper interconnects. Based on the QMS and FTIR data, this enhancement could be attributed to the role of hydrogen in assisting in the removal of tmvs from (tmvs)Cusp{I}(hfac), thus enhancing the conversion of Cusp{I}(hfac) intermediates to Cusp{o} and Cusp{II}(hfac)sb2 and providing a wider process window with higher conversion efficiency. In addition, in-situ real time QMS studies were performed of the gas phase evolution and decomposition pathways of (tmvs)Cusp{I}(hfac) during thermal CVD of copper. The QMS investigations focused on determining the ionization efficiency curves and appearance potentials of (tmvs)Cusp{I}(hfac) under real CVD processing conditions. The resulting curves and associated potentials were then employed to identify the most likely precursor decomposition pathways and examine relevant implications for thermal CVD of copper from (tmvs)Cusp{I}(hfac). Finally, a hydrogen-plasma assisted CVD (PACVD) process was developed for the growth of device quality gold for incorporation as dopant in emerging Cu CVD based metallization interconnects. In particular, it was demonstrated that the PACVD gold process window identified can maintain very low gold deposition rates (gold is a promising in-situ Cu doping technique

  13. Major leaching processes of combustion residues - Characterisation, modelling and experimental investigation

    Energy Technology Data Exchange (ETDEWEB)

    Yan Jinying

    1998-12-31

    Characterising leaching behaviour provides ample evidence to identify the major leaching processes of combustion residues. Neutralisation and chemical weathering govern the leaching reactions and control the release of elements from combustion residues, and are thus considered to be the major leaching processes. According to experimental investigations and geochemical simulations, the leaching kinetics of buffering materials are key issues for the understanding of the neutralizing processes. The acid neutralizing capacity at different pH levels depends mainly on the mineralogy of the combustion residues. In combustion residues, the dissolution of glass phases is expected to play an important role in a long-term neutralizing process. The neutralizing process in a flow system is significantly different from that in a batch system. The neutralizing ability of a combustion residue may be strongly affected by solute transport and carbonation reactions in a natural leaching environment. The chemical weathering mainly involves the matrix of combustion residues consisting mostly of glass phases. The dissolution kinetics of waste glass and other possible processes involved in the chemical weathering have been investigated and incorporated into a kinetic reactive transport model. Most important processes in the chemical weathering can be simulated simultaneously using this model. The results show that there is a complicated relationship between the factors controlling the long-term chemical weathering. The environmental impact of the glass dissolution cannot be neglected. Although the glass dissolution provides considerable buffering capacity in long-term weathering, the carbonate is usually a dominant buffering mineral in actual weathering processes. The transformation of carbonate should be considered as an important process in the chemical weathering. The formation of secondary minerals may considerably alter the mineralogy of the waste, and thus change the leaching

  14. In situ characterization of the deformation and failure behavior of non-stochastic porous structures processed by selective laser melting

    Energy Technology Data Exchange (ETDEWEB)

    Gorny, B.; Niendorf, T.; Lackmann, J. [Lehrstuhl fuer Werkstoffkunde (Materials Science), University of Paderborn, Pohlweg 47-49, 33098 Paderborn (Germany); Thoene, M.; Troester, T. [Lehrstuhl fuer Leichtbau im Automobil (Automotive Lightweight Construction), University of Paderborn, Pohlweg 47-49, 33098 Paderborn (Germany); Direct Manufacturing Research Center (DMRC), Mersinweg 3, 33098 Paderborn (Germany); Maier, H.J., E-mail: hmaier@mail.upb.de [Lehrstuhl fuer Werkstoffkunde (Materials Science), University of Paderborn, Pohlweg 47-49, 33098 Paderborn (Germany)

    2011-10-15

    Highlights: {yields} The present study focused on deformation behavior and failure mechanisms in lattice structure produced by selective laser melting (SLM). {yields} It is demonstrated that heat treatments can be used to increase the energy absorption of an SLM-processed structure. {yields} An in situ testing procedure was introduced, where local strains were calculated by digital image correlation {yields} Shear failure could be predicted by localization using Tresca strains. {yields} The approach employed provides a means to understand the microstructure-mechanical property-local deformation relationship. - Abstract: Cellular materials are promising candidates for load adapted light-weight structures. Direct manufacturing (DM) tools are effective methods to produce non-stochastic structures. Many DM studies currently focus on optimization of the geometric nature of the structures obtained. The literature available so far reports on the mechanical properties but local deformation mechanisms are not taken into account. In order to fill this gap, the current study addresses the deformation behavior of a lattice structure produced by selective laser melting (SLM) on the local scale by means of a comprehensive experimental in situ approach, including electron backscatter diffraction, scanning electron microscopy and digital image correlation. SLM-processed as well as heat treated lattice structures made from TiAl6V4 alloy were employed for mechanical testing. It is demonstrated that the current approach provides means to understand the microstructure-mechanical property-local deformation relationship to allow for optimization of load adapted lattice structures.

  15. Enhancement of Biodiesel Production from Marine Alga, Scenedesmus sp. through In Situ Transesterification Process Associated with Acidic Catalyst

    Directory of Open Access Journals (Sweden)

    Ga Vin Kim

    2014-01-01

    Full Text Available The aim of this study was to increase the yield of biodiesel produced by Scenedesmus sp. through in situ transesterification by optimizing various process parameters. Based on the orthogonal matrix analysis for the acidic catalyst, the effects of the factors decreased in the order of reaction temperature (47.5% > solvent quantity (26.7% > reaction time (17.5% > catalyst amount (8.3%. Based on a Taguchi analysis, the effects of the factors decreased in the order of solvent ratio (34.36% > catalyst (28.62% > time (19.72% > temperature (17.32%. The overall biodiesel production appeared to be better using NaOH as an alkaline catalyst rather than using H2SO4 in an acidic process, at 55.07 ± 2.18% (based on lipid weight versus 48.41 ± 0.21%. However, in considering the purified biodiesel, it was found that the acidic catalyst was approximately 2.5 times more efficient than the alkaline catalyst under the following optimal conditions: temperature of 70°C (level 2, reaction time of 10 hrs (level 2, catalyst amount of 5% (level 3, and biomass to solvent ratio of 1 : 15 (level 2, respectively. These results clearly demonstrated that the acidic solvent, which combined oil extraction with in situ transesterification, was an effective catalyst for the production of high-quantity, high-quality biodiesel from a Scenedesmus sp.

  16. In situ observation of dynamic electrodeposition processes by soft x-ray fluorescence microspectroscopy and keyhole coherent diffractive imaging

    Science.gov (United States)

    Bozzini, Benedetto; Kourousias, George; Gianoncelli, Alessandra

    2017-03-01

    This paper describes two novel in situ microspectroscopic approaches to the dynamic study of electrodeposition processes: x-ray fluorescence (XRF) mapping with submicrometric space resolution and keyhole coherent diffractive imaging (kCDI) with nanometric lateral resolution. As a case study, we consider the pulse-plating of nanocomposites with polypyrrole matrix and Mn x Co y O z dispersoids, a prospective cathode material for zinc-air batteries. This study is centred on the detailed measurement of the elemental distributions developing in two representative subsequent growth steps, based on the combination of in situ identical-location XRF microspectroscopy—accompanied by soft-x ray absorption microscopy—and kCDI. XRF discloses space and time distributions of the two electrodeposited metals and kCDI on the one hand allows nanometric resolution and on the other hand provides complementary absorption as well as phase contrast modes. The joint information derived from these two microspectroscopies allows measurement of otherwise inaccessible observables that are a prerequisite for electrodeposition modelling and control accounting for dynamic localization processes.

  17. Stability investigations of zinc and cobalt precipitates immobilized by in situ bioprecipitation (ISBP) process

    Energy Technology Data Exchange (ETDEWEB)

    Satyawali, Yamini; Schols, Edo; Van Roy, Sandra; Dejonghe, Winnie; Diels, Ludo [Separation and Conversion Technology, Flemish Institute for Technological Research (VITO), Boeretang 200, 2400 Mol (Belgium); Vanbroekhoven, Karolien, E-mail: karolien.vanbroekhoven@vito.be [Separation and Conversion Technology, Flemish Institute for Technological Research (VITO), Boeretang 200, 2400 Mol (Belgium)

    2010-09-15

    In situ bioprecipitation (ISBP), which involves immobilizing the metals as precipitates (mainly sulphides) in the solid phase, is an effective method of metal removal from contaminated groundwater. This study investigated the stability of metal precipitates formed after ISBP in two different solid-liquid matrices (artificial and natural). The artificial matrix consisted of sand, Zn (200 mg L{sup -1}), artificial groundwater and a carbon source (electron donor). Here the stability of the Zn precipitates was evaluated by manipulation of redox and pH. The natural system matrices included aquifer material and groundwater samples collected from three different metal (Zn and Co) contaminated sites and different carbon sources were provided as electron donors. In the natural matrices, metal precipitates stability was assessed by changing aquifer redox conditions, sequential extraction, and BIOMET assay. The results indicated that, in the artificial matrix, redox manipulation did not impact the Zn precipitates. However the sequential pH change proved detrimental, releasing 58% of the precipitated Zn back into liquid phase. In natural matrices, the applied carbon source largely affected the stability of metal precipitates. Elemental analysis performed on the precipitates formed in natural matrix showed that the main elements of the precipitates were sulphur with Zn and Co.

  18. Hydro-physical processes at the plunge point: an analysis using satellite and in situ data

    Directory of Open Access Journals (Sweden)

    A. T. Assireu

    2011-12-01

    Full Text Available The plunge point is the main mixing point between river and epilimnetic reservoir water. Plunge point monitoring is essential for understanding the behavior of density currents and their implications for reservoir. The use of satellite imagery products from different sensors (Landsat TM band 6 thermal signatures and visible channels for the characterization of the river-reservoir transition zone is presented in this study. It is demonstrated the feasibility of using Landsat TM band imagery to discern the subsurface river plumes and the plunge point. The spatial variability of the plunge point evident in the hydrologic data illustrates the advantages of synoptic satellite measurements over in situ point measurements alone to detect the river-reservoir transition zone. During the dry season, when the river-reservoir water temperature differences vanish and the river circulation is characterized by interflow-overflow, the river water inserts into the upper layers of the reservoir, affecting water quality. The results indicate a good agreement between hydrologic and satellite data and that the joint use of thermal and visible channel data for the operational monitoring of a plunge point is feasible. The deduced information about the density current from this study could potentially be assimilated into numerical models and hence be of significant interest for environmental and climatological research.

  19. Stability investigations of zinc and cobalt precipitates immobilized by in situ bioprecipitation (ISBP) process

    KAUST Repository

    Satyawali, Yamini

    2010-09-01

    In situ bioprecipitation (ISBP), which involves immobilizing the metals as precipitates (mainly sulphides) in the solid phase, is an effective method of metal removal from contaminated groundwater. This study investigated the stability of metal precipitates formed after ISBP in two different solid-liquid matrices (artificial and natural). The artificial matrix consisted of sand, Zn (200mgL-1), artificial groundwater and a carbon source (electron donor). Here the stability of the Zn precipitates was evaluated by manipulation of redox and pH. The natural system matrices included aquifer material and groundwater samples collected from three different metal (Zn and Co) contaminated sites and different carbon sources were provided as electron donors. In the natural matrices, metal precipitates stability was assessed by changing aquifer redox conditions, sequential extraction, and BIOMET® assay. The results indicated that, in the artificial matrix, redox manipulation did not impact the Zn precipitates. However the sequential pH change proved detrimental, releasing 58% of the precipitated Zn back into liquid phase. In natural matrices, the applied carbon source largely affected the stability of metal precipitates. Elemental analysis performed on the precipitates formed in natural matrix showed that the main elements of the precipitates were sulphur with Zn and Co. © 2010 Elsevier B.V.

  20. Dual phase high-temperature membranes for CO2 separation - performance assessment in post- and pre-combustion processes.

    Science.gov (United States)

    Anantharaman, Rahul; Peters, Thijs; Xing, Wen; Fontaine, Marie-Laure; Bredesen, Rune

    2016-10-20

    Dual phase membranes are highly CO2-selective membranes with an operating temperature above 400 °C. The focus of this work is to quantify the potential of dual phase membranes in pre- and post-combustion CO2 capture processes. The process evaluations show that the dual phase membranes integrated with an NGCC power plant for CO2 capture are not competitive with the MEA process for post-combustion capture. However, dual phase membrane concepts outperform the reference Selexol technology for pre-combustion CO2 capture in an IGCC process. The two processes evaluated in this work, post-combustion NGCC and pre-combustion IGCC, represent extremes in CO2 partial pressure fed to the separation unit. Based on the evaluations it is expected that dual phase membranes could be competitive for post-combustion capture from a pulverized coal fired power plant (PCC) and pre-combustion capture from an Integrated Reforming Cycle (IRCC).

  1. Applications of Combustion Research on the International Space Station to Industrial Processes on Earth

    Science.gov (United States)

    Schowengerdt, F.

    2002-01-01

    The mission of the Center for Commercial Applications of Combustion in Space (CCACS) at the Colorado School of Mines is to conduct research and educate students in scientific areas related to combustion. The center focuses on those areas where results can be applied to the development of commercial products and processes and where the research can benefit from the unique properties of space. The center is planning combustion-related research aboard the International Space Station (ISS) that will further this mission. The research will be conducted in the two ISS facilities designed for combustion experiments, Space-DRUMSTM and the Combustion Integrated Rack (CIR) of the Fluids and Combustion Facility. Space-DRUMSTM is a containerless processing facility employing dynamic acoustic positioning. Guigne International, Ltd. of St. John's, Newfoundland, a CCACS member, is developing the facility in partnership with Astrium Space- Infrastructure and Teledyne Brown Engineering. This universal processing facility can handle large samples with virtually complete vibration isolation from the space station and no contamination from the experimental processing chamber. The CCACS research to be done in Space-DRUMSTM includes combustion synthesis of glass-ceramics and porous materials, nanoparticle synthesis, catalytic combustion, fluid physics and granular materials. The launch of Space-DRUMSTM to the ISS is currently scheduled for ULF-1 in January of 2003. The CIR is being developed by NASA-Glenn Research Center, and is a general-purpose combustion furnace designed to accommodate a wide range of scientific experiments. The CCACS research to be done in the CIR includes water mist fire suppression, flame synthesis of ceramic powders, nanoparticle synthesis and catalytic combustion. The CIR is currently under development, with an expected launch date in the 2005 timeframe. The applications of this combustion research in manufacturing and processing industries are far

  2. In situ biosynthesis of bacterial nanocellulose-CaCO{sub 3} hybrid bionanocomposite: One-step process

    Energy Technology Data Exchange (ETDEWEB)

    Mohammadkazemi, Faranak, E-mail: f_mkazemi@sbu.ac.ir [Department of Cellulose and Paper Technology, Faculty of New Technologies Engineering, Shahid Beheshti University, Science and Research Campus, Zirab, Savadkooh, Mazandaran (Iran, Islamic Republic of); Faria, Marisa; Cordeiro, Nereida [Faculty of Exact Science and Engineering, University of Madeira, Funchal (Portugal)

    2016-08-01

    In this work, a simple and green route to the synthesis of the bacterial nanocellulose-calcium carbonate (BNC/CaCO{sub 3}) hybrid bionanocomposites using one-step in situ biosynthesis was studied. The CaCO{sub 3} was incorporated in the bacterial nanocellulose structure during the cellulose biosynthesis by Gluconacetobacter xylinus PTCC 1734 bacteria. Hestrin-Schramm (HS) and Zhou (Z) culture media were used to the hybrid bionanocomposites production and the effect of ethanol addition was investigated. Attenuated total reflection Fourier transform infrared spectroscopy, field emission scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, inverse gas chromatography and thermogravimetric analysis were used to characterize the samples. The experimental results demonstrated that the ethanol and culture medium play an important role in the BNC/CaCO{sub 3} hybrid bionanocomposites production, structure and properties. The BNC/CaCO{sub 3} biosynthesized in Z culture medium revealed higher O/C ratio and amphoteric surface character, which justify the highest CaCO{sub 3} content incorporation. The CaCO{sub 3} was incorporated into the cellulosic matrix decreasing the bacterial nanocellulose crystallinity. This work reveals the high potential of in situ biosynthesis of BNC/CaCO{sub 3} hybrid bionanocomposites and opens a new way to the high value-added applications of bacterial nanocellulose. - Graphical Abstract: Display Omitted - Highlights: • BNC/CaCO{sub 3} hybrid bionanocomposites were produced using in situ biosynthesis process. • Ethanol and culture medium play an important role in the production and properties. • Z-BNC/CaCO{sub 3} bionanocomposites revealed higher O/C ratio and amphoteric surface character. • CaCO{sub 3} incorporated into the BNC decreased crystallinity.

  3. In situ Raman characterization of minerals and degradation processes in a variety of cultural and geological heritage sites

    Science.gov (United States)

    Gázquez, F.; Rull, F.; Sanz-Arranz, A.; Medina, J.; Calaforra, J. M.; de las Heras, C.; Lasheras, J. A.

    2017-02-01

    We test the capabilities of in situ Raman spectroscopy for non-destructive analysis of degradation processes in invaluable masterpieces, as well as for the characterization of minerals and prehistoric rock-art in caves. To this end, we have studied the mechanism of decay suffered by the 15th-century limestone sculptures that decorate the retro-choir of Burgos Cathedral (N Spain). In situ Raman probe detected hydrated sulfate and nitrate minerals on the sculptures, which are responsible for the decay of the original limestone. In addition, in situ Raman analyses were performed on unique speleothems in El Soplao Cave (Cantabria, N Spain) and in the Gruta de las Maravillas (Aracena, SW Spain). Unusual cave minerals were detected in El Soplao Cave, such as hydromagnesite (Mg5(CO3)4(OH)2·4H2O), as well as ferromanganese oxides in the black biogenic speleothems recently discovered in this cavern. In the Gruta de las Maravillas, gypsum (CaSO4·2H2O) was identified for the first time, as part of the oldest cave materials, so providing additional evidence of hypogenic mechanisms that occurred in this cave during earlier stages of its formation. Finally, we present preliminary analyses of several cave paintings in the renowned "Polychrome Hall" of Altamira Cave (Cantabria, N. Spain). Hematite (Fe2O3) is the most abundant mineral phase, which provides the characteristic ochre-reddish color to the Altamira bison and deer paintings. Thus, portable Raman spectroscopy is demonstrated to be an analytical technique compatible with preserving our cultural and natural heritage, since the analysis does not require physical contact between the Raman head and the analyzed items.

  4. In situ Raman characterization of minerals and degradation processes in a variety of cultural and geological heritage sites.

    Science.gov (United States)

    Gázquez, F; Rull, F; Sanz-Arranz, A; Medina, J; Calaforra, J M; de Las Heras, C; Lasheras, J A

    2017-02-05

    We test the capabilities of in situ Raman spectroscopy for non-destructive analysis of degradation processes in invaluable masterpieces, as well as for the characterization of minerals and prehistoric rock-art in caves. To this end, we have studied the mechanism of decay suffered by the 15th-century limestone sculptures that decorate the retro-choir of Burgos Cathedral (N Spain). In situ Raman probe detected hydrated sulfate and nitrate minerals on the sculptures, which are responsible for the decay of the original limestone. In addition, in situ Raman analyses were performed on unique speleothems in El Soplao Cave (Cantabria, N Spain) and in the Gruta de las Maravillas (Aracena, SW Spain). Unusual cave minerals were detected in El Soplao Cave, such as hydromagnesite (Mg5(CO3)4(OH)2·4H2O), as well as ferromanganese oxides in the black biogenic speleothems recently discovered in this cavern. In the Gruta de las Maravillas, gypsum (CaSO4·2H2O) was identified for the first time, as part of the oldest cave materials, so providing additional evidence of hypogenic mechanisms that occurred in this cave during earlier stages of its formation. Finally, we present preliminary analyses of several cave paintings in the renowned "Polychrome Hall" of Altamira Cave (Cantabria, N. Spain). Hematite (Fe2O3) is the most abundant mineral phase, which provides the characteristic ochre-reddish color to the Altamira bison and deer paintings. Thus, portable Raman spectroscopy is demonstrated to be an analytical technique compatible with preserving our cultural and natural heritage, since the analysis does not require physical contact between the Raman head and the analyzed items. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Innovative oxy-coal combustion process suitable for future and more efficient zero emission power plants

    Energy Technology Data Exchange (ETDEWEB)

    Benelli, G.; Malavasi, M.; Girardi, G. [ENEL Ricerca (Italy)

    2007-07-01

    The problem with CO{sub 2} capture from a flue gas stream is related to its low concentration, which makes the process of separation very energy-intensive, complex and, as a result, expensive. The CO{sub 2} separation process can be optimized by increasing the concentration of CO{sub 2} and reducing nitrogen concentration in the stream as it happens, in the oxy-fuel combustion process. In such a case, the oxidant flow is typically a mixture of oxygen, steam and carbon dioxide, with a very low concentration of nitrogen. Since the oxy-combustion process leads to very high temperatures, flue gases must be circulating through the chemical reactor to keep the combustion adiabatic temperature below acceptable values, due to the limits imposed by material resistance. This paper focuses on an innovative oxy-coal combustion process named ISOTHERM{reg_sign}, based on a flameless combustion technique which is mentioned in recent literature also as 'Mild' combustion. The combustion process takes place within a pressurized and refractory-lined furnace, approaching temperatures close to 2000 K. The process has been experienced at pressurized conditions up to 4 bar on a 5 MW pilot plant for thousands of hours. In this paper, starting from a detailed description of the process, results obtained by the preliminary experimental tests are presented and discussed. Then, a development and demonstration program to assess the suitability of this technology for zero emission power generation at large scale in one of the units of Brindisi power station is presented. 10 refs., 5 figs., 2 tabs.

  6. Fluidized-bed combustion process evaluation and program support. Quarterly report, January-March 1980

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, I.; Podolski, W.F.; Swift, W.M.; Henry, R.F.; Hanway, J.E.; Griggs, K.E.; Herzenberg, C.; Helt, J.E.; Carls, E.L.

    1980-12-01

    Argonne National Laboratory is undertaking several tasks primarily in support of the pressurized fluidized-bed combustion project management team at Morgantown Energy Technology Center. Work is under way to provide fluidized-bed combustion process evaluation and program support to METC, determination of the state of the art of instrumentation for FBC applications, evaluation of the performance capability of cyclones for hot-gas cleaning in PFBC systems, and an initial assessment of methods for the measurement of sodium sulfate dew point.

  7. Optical investigations of combustion process in SI and CI engines fuelled with butanol blends

    Energy Technology Data Exchange (ETDEWEB)

    Marchitto, L.; Mazzei, A.; Merola, S.S.; Tornatore, C. [CNR Napoli, Naples (Italy). Istituto Motori; Valentino, G.

    2013-06-01

    The use of alternative fuels, as biodiesel and ethanol, for light duty engines to approach the target of low exhaust emissions without fuel economy and performance penalty has been widely investigated. Recently it is growing the interest in the butanol and bio-butanol as viable alternatives either single or blended with conventional based fuels. In this paper, butanol effects on combustion processes were investigated through conventional methods and optical diagnostics applied in the combustion chamber of a compression ignition engine and of a spark ignition engine. Blends of diesel and n-butanol were used in a common rail DI diesel engine running at different operating conditions. Fuel injection timing and oxygen at the intake were changed in a single cylinder compression ignition engine equipped with common rail multi-jets injection system. Spray combustion and pollutant formation were investigated though UV-visible digital imaging and natural emission spectroscopy. Flame emissions and spectroscopy were applied in an optically accessible cylinder of a port fuel-injection, spark-ignition engine with an external boosting device. The engine worked with a stoichiometric mixture at medium speed and boosting in wide open throttle condition. Normal and knocking combustion was tested. Experiments in both the engines demonstrated that butanol allowed to reduce carbonaceous compounds formation and soot emission and to decrease unpleasant effects related to the combustion process such as the fuel deposition burning. Moreover some emission bands of OH radicals could be used as feature of different phenomena related to the combustion process. (orig.)

  8. Numerical Studies on Controlling Gaseous Fuel Combustion by Managing the Combustion Process of Diesel Pilot Dose in a Dual-Fuel Engine

    Directory of Open Access Journals (Sweden)

    Mikulski Maciej

    2015-06-01

    Full Text Available Protection of the environment and counteracting global warming require finding alternative sources of energy. One of the methods of generating energy from environmentally friendly sources is increasing the share of gaseous fuels in the total energy balance. The use of these fuels in compression-ignition (CI engines is difficult due to their relatively high autoignition temperature. One solution for using these fuels in CI engines is operating in a dualfuel mode, where the air and gas mixture is ignited with a liquid fuel dose. In this method, a series of relatively complex chemical processes occur in the engine's combustion chamber, related to the combustion of individual fuel fractions that interact with one another. Analysis of combustion of specific fuels in this type of fuel injection to the engine is difficult due to the fact that combustion of both fuel fractions takes place simultaneously. Simulation experiments can be used to analyse the impact of diesel fuel combustion on gaseous fuel combustion. In this paper, we discuss the results of simulation tests of combustion, based on the proprietary multiphase model of a dual-fuel engine. The results obtained from the simulation allow for analysis of the combustion process of individual fuels separately, which expands the knowledge obtained from experimental tests on the engine.

  9. Calibrating IR cameras for in-situ temperature measurement during the electron beam melt processing of Inconel 718 and Ti-Al6-V4

    Science.gov (United States)

    Dinwiddie, R. B.; Kirka, M. M.; Lloyd, P. D.; Dehoff, R. R.; Lowe, L. E.; Marlow, G. S.

    2016-05-01

    High performance mid-wave infrared (IR) cameras are used for in-situ electron beam melt process monitoring and temperature measurements. Since standard factory calibrations are insufficient due to very low transmissions of the leaded glass window required for X-ray absorption, two techniques for temperature calibrations are compared. In-situ measurement of emittance will also be discussed. Ultimately, these imaging systems have the potential for routine use for online quality assurance and feedback control.

  10. Numerical modelling of biomass combustion: Solid conversion processes in a fixed bed furnace

    Science.gov (United States)

    Karim, Md. Rezwanul; Naser, Jamal

    2017-06-01

    Increasing demand for energy and rising concerns over global warming has urged the use of renewable energy sources to carry a sustainable development of the world. Bio mass is a renewable energy which has become an important fuel to produce thermal energy or electricity. It is an eco-friendly source of energy as it reduces carbon dioxide emissions. Combustion of solid biomass is a complex phenomenon due to its large varieties and physical structures. Among various systems, fixed bed combustion is the most commonly used technique for thermal conversion of solid biomass. But inadequate knowledge on complex solid conversion processes has limited the development of such combustion system. Numerical modelling of this combustion system has some advantages over experimental analysis. Many important system parameters (e.g. temperature, density, solid fraction) can be estimated inside the entire domain under different working conditions. In this work, a complete numerical model is used for solid conversion processes of biomass combustion in a fixed bed furnace. The combustion system is divided in to solid and gas phase. This model includes several sub models to characterize the solid phase of the combustion with several variables. User defined subroutines are used to introduce solid phase variables in commercial CFD code. Gas phase of combustion is resolved using built-in module of CFD code. Heat transfer model is modified to predict the temperature of solid and gas phases with special radiation heat transfer solution for considering the high absorptivity of the medium. Considering all solid conversion processes the solid phase variables are evaluated. Results obtained are discussed with reference from an experimental burner.

  11. In-situ, real-time, studies of film growth processes using ion scattering and direct recoil spectroscopy techniques.

    Energy Technology Data Exchange (ETDEWEB)

    Smentkowski, V. S.

    1999-04-22

    Time-of-flight ion scattering and recoil spectroscopy (TOF-ISARS) enables the characterization of the composition and structure of surfaces with 1-2 monolayer specificity. It will be shown that surface analysis is possible at ambient pressures greater than 3 mTorr using TOF-ISARS techniques; allowing for real-time, in situ studies of film growth processes. TOF-ISARS comprises three analytical techniques: ion scattering spectroscopy (ISS), which detects the backscattered primary ion beam; direct recoil spectroscopy (DRS), which detects the surface species recoiled into the forward scattering direction; and mass spectroscopy of recoiled ions (MSRI), which is 3 variant of DRS capable of isotopic resolution for all surface species--including H and He. The advantages and limitations of each of these techniques will be discussed. The use of the three TOF-ISARS methods for real-time, in situ film growth studies at high ambient pressures will be illustrated. It will be shown that MSRI analysis is possible during sputter deposition. It will be also be demonstrated that the analyzer used for MSRI can also be used for time of flight secondary ion mass spectroscopy (TOF-SIMS) under high vacuum conditions. The use of a single analyzer to perform the complimentary surface analytical techniques of MSRI and SIMS is unique. The dwd functionality of the MSRI analyzer provides surface information not obtained when either MSRI or SIMS is used independently.

  12. Antibacterial and hemolysis activity of polypyrrole nanotubes decorated with silver nanoparticles by an in-situ reduction process.

    Science.gov (United States)

    Upadhyay, J; Kumar, A; Gogoi, B; Buragohain, A K

    2015-09-01

    Polypyrrole nanotube-silver nanoparticle nanocomposites (PPy-NTs:Ag-NPs) have been synthesized by in-situ reduction of silver nitrate (AgNO3) to suppress the agglomeration of Ag-NPs. The morphology and chemical structure of the nanocomposites have been studied by HRTEM, SEM, XRD, FTIR and UV-vis spectroscopy. The average diameter of the polypyrrole nanotubes (PPy-NTs) is measured to be 130.59±5.5 nm with their length in the micrometer range, while the silver nanoparticles (Ag-NPs) exhibit spherical shape with an average diameter of 23.12±3.23 nm. In-vitro blood compatibility of the nanocomposites has been carried out via hemolysis assay. Antimicrobial activity of the nanocomposites has been investigated with Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria. The results depict that the hemolysis and antimicrobial activities of the nanocomposites increase with increasing Ag-NP concentration that can be controlled by the AgNO3 precursor concentration in the in-situ process. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Results from an in-situ pore water chemistry experiment in opalinus clay: evidence of microbially mediated anaerobic redox processes

    Energy Technology Data Exchange (ETDEWEB)

    Wersin, P.; Mettler, S. [NAGRA - National Cooperative for the Disposal of Radioactive Waste, Wettingen (Switzerland); Canniere, P. de [SCK-CEN, Mol (Belgium); Pearson, F.J. [Ground-Water Geochemistry, New Bern (United States); Gaucher, E. [BRGM, 75 - Paris (France); Hohener, P. [BioRem, CH (Switzerland); Eichinger, L. [Hydroisotop, Schweitenkirchen (Germany); Mader, U. [Bern Univ., CH (Switzerland); Vinsot, A. [Agence Nationale pour la Gestion des Dechets Radioactifs (ANDRA), 92 - Chatenay Malabry (France); Gabler, H.E. [Federal Institute for Geosciences and Natural Resources (BGR), Hannover (Germany); Hama, K. [JNC - Japan Nuclear Cycle Development Institute (JNC) Horonobe (Japan); Hernan, P. [ENRESA, Madrid (Spain)

    2005-07-01

    Low permeability argillaceous rocks are considered potential host rocks for radioactive waste disposal in a number of countries. Characterisation of pore water chemistry is important for assessing radionuclide behaviour, but technically challenging because of intimate clay-water association. The application of different techniques, such as in-situ extraction, squeezing and leaching has led to improved understanding. However, because of potential experimental artefacts (e.g. degassing of CO{sub 2}, ingress of O{sub 2} ), significant uncertainties remain, especially with regard to pH/pCO{sub 2} and Eh conditions. Moreover, the pore water chemistry may be perturbed by the drilling procedure itself, thus leading to oxidation and biodegradation effects. In order to reduce uncertainties mentioned above and to gain deeper insight into geochemical processes regulating pH and Eh, the internationally supported Pore water Chemistry (PC) experiment was started at the Mont Terri Rock Laboratory in 2002. The basis of the study is an in-situ experiment employing the diffusive equilibration method. The field study was complemented with lab investigations which include chemical analyses for principal inorganic solutes, for reduced sulphur species and for a variety of specific organic compounds, gas measurements of core samples and a core infiltration study based on advective displacement. (authors)

  14. Evaluation of Centrifugal Casting Process Parameters for In Situ Fabricated Functionally Gradient Fe-TiC Composite

    Science.gov (United States)

    Rahimipour, Mohammad Reza; Sobhani, Manoochehr

    2013-10-01

    A gradient Fe-TiC composite was successfully produced via combination of in situ reaction with centrifugal casting techniques. Additionally, some of the effective parameters of the centrifugal casting process have been studied. Cast iron and ferrotitanium, which were used as raw materials, were melted using a high-frequency induction furnace coupled with centrifugal equipment. The microstructure and phase characterization of the fabricated composite was studied by scanning electron microscopy, optical microscopy, and X-ray diffraction. The results show that the production of a pearlite matrix composite reinforced by TiC particles is feasible. The distribution of TiC in the pearlitic matrix is completely uneven as a result of density difference between molten medium and TiC in the centrifugal casting process.

  15. A whole biodiesel conversion process combining isolation, cultivation and in situ supercritical methanol transesterification of native microalgae.

    Science.gov (United States)

    Jazzar, Souhir; Quesada-Medina, Joaquín; Olivares-Carrillo, Pilar; Marzouki, Mohamed Néjib; Acién-Fernández, Francisco Gabriel; Fernández-Sevilla, José María; Molina-Grima, Emilio; Smaali, Issam

    2015-08-01

    A coupled process combining microalgae production with direct supercritical biodiesel conversion using a reduced number of operating steps is proposed in this work. Two newly isolated native microalgae strains, identified as Chlorella sp. and Nannochloris sp., were cultivated in both batch and continuous modes. Maximum productivities were achieved during continuous cultures with 318mg/lday and 256mg/lday for Chlorella sp. and Nannochloris sp., respectively. Microalgae were further characterized by determining their photosynthetic performance and nutrient removal efficiency. Biodiesel was produced by catalyst-free in situ supercritical methanol transesterification of wet unwashed algal biomass (75wt.% of moisture). Maximum biodiesel yields of 45.62wt.% and 21.79wt.% were reached for Chlorella sp. and Nannochloris sp., respectively. The analysis of polyunsaturated fatty acids of Chlorella sp. showed a decrease in their proportion when comparing conventional and supercritical transesterification processes (from 37.4% to 13.9%, respectively), thus improving the quality of the biodiesel.

  16. The Mg{sub 2}Si phase evolution during thermomechanical processing of in-situ aluminum matrix macro-composite

    Energy Technology Data Exchange (ETDEWEB)

    Shafieizad, A.H. [The Complex Laboratory of Hot Deformation & Thermomechanical Processing of High Performance Engineering Materials, School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran (Iran, Islamic Republic of); Zarei-Hanzaki, A., E-mail: Zareih@ut.ac.ir [The Complex Laboratory of Hot Deformation & Thermomechanical Processing of High Performance Engineering Materials, School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran (Iran, Islamic Republic of); Abedi, H.R. [The Complex Laboratory of Hot Deformation & Thermomechanical Processing of High Performance Engineering Materials, School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran (Iran, Islamic Republic of); Al-Fadhalah, K.J. [Department of Mechanical Engineering, College of Engineering & Petroleum, Kuwait University, P.O. Box 5969, Safat 13060 (Kuwait)

    2015-09-17

    The microstructure and flow stress behavior of thermomechanically processed Al–Cu/Mg{sub 2}Si in-situ composite was studied emphasizing the evolution of primary and secondary reinforcement phases. Toward this end, the hot compression tests were conducted over the wide range of temperature (300–500 °C) and strain rate (0.001–0.1 s{sup −1}). Both the temperature and strain rate are found to possess a significant effect on the microstructural characteristics where a considerable softening is identified specially at low temperature regime. Besides the occurrence of restoration processes (mainly particle stimulated nucleation) the dynamic evolution of the reinforcements is introduced as the main factors affecting the reported softening. In this regard, the mechanical fragmentation, thermal disintegration, micro-buckling, coalescence and spheroidization of the primary and secondary particles are quantitatively and qualitatively addressed through a comprehensive scanning electron microscopy studies.

  17. In situ monitoring of discharge/charge processes in Li-O2 batteries by electrochemical impedance spectroscopy

    Science.gov (United States)

    Landa-Medrano, Imanol; Ruiz de Larramendi, Idoia; Ortiz-Vitoriano, Nagore; Pinedo, Ricardo; Ignacio Ruiz de Larramendi, José; Rojo, Teófilo

    2014-03-01

    Gaining insight into the reaction mechanisms underway during charge and discharge in Li-air batteries is essential to allow the target development of improved power and performance devices. This work reports the in situ monitoring of Li-air cells by electrochemical impedance spectroscopy and, for the first time, the development of an electrochemical model allowing the identification and attribution of the processes involved. The voltage at which each reaction product forms has been identified, including Li2O2 or Li2CO3 during discharge, together with the delithiation of the outer part of Li2O2 and oxidation reactions and electrolyte decomposition. The developed model can be used as a valuable tool for the optimisation of composition and structure of the air electrode through the investigation of the resistance associated with each process.

  18. In vitro study of hydroxyapatite/polycaprolactone (HA/PCL) nanocomposite synthesized by an in situ sol-gel process

    Energy Technology Data Exchange (ETDEWEB)

    Rezaei, A.; Mohammadi, M.R., E-mail: mohammadi@sharif.edu

    2013-01-01

    Hydroxyapatite (HA) is the most substantial mineral constituent of a bone which has been extensively used in medicine as implantable materials, owing to its good biocompatibility, bioactivity high osteoconductive, and/or osteoinductive properties. Nevertheless, its mechanical property is not utmost appropriate for a bone substitution. Therefore, a composite consist of HA and a biodegradable polymer is usually prepared to generate an apt bone scaffold. In the present work polycaprolactone (PCL), a newly remarkable biocompatible and biodegradable polymer, was employed as a matrix and hydroxyapatite nanoparticles were used as a reinforcement element of the composite. HA/PCL nanocomposites were synthesized by a new in situ sol-gel process using calcium hydroxide and phosphoric acid precursors in the presence of Tetrahydrofuran (THF) as a solvent. Chemical and physical characteristics of the nanocomposite were studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared (FTIR) analyses. The results indicated that pure HA nanoparticles were well-incorporated and homogenously dispersed in the PCL matrix. It was found that the mechanical property of PCL was improved by addition of 20 wt.% HA nanoparticles. Furthermore, the biological property of nanocomposites was investigated under in vitro condition. For this purpose, HA/PCL scaffolds were prepared through a salt leaching process and immersed in a saturated simulated body fluid (SBF) after 3 and 7 days. It was found that a uniform layer of biomimetic HA could be deposited on the surface of HA/PCL scaffolds. Therefore, the prepared HA/PCL scaffolds showed good potential for bone tissue engineering and could be used for many clinical applications in orthopedic and maxillofacial surgery. - Graphical abstract: Preparation of HA/PCL nanocomposite and scaffold by an in situ sol-gel process is shown. Highlights: Black-Right-Pointing-Pointer Hydroxyapatite

  19. In-Situ Simulation

    DEFF Research Database (Denmark)

    Bjerregaard, Anders Thais; Slot, Susanne; Paltved, Charlotte

    2015-01-01

    Introduction: In situ simulation offers on-site training to healthcare professionals. It refers to a training strategy where simulation technology is integrated into the clinical encounter. Training in the simulation laboratory does not easily tap into situational resources, e.g. individual, team......, and organisational characteristic. Therefore, it might fail to fully mimic real clinical team processes. Though research on in situ simulation in healthcare is in its infancy, literature is abundant on patient safety and team training1. Patient safety reporting systems that identify risks to patients can improve...... offered in situ simulation faculty with a model for integrating reported critical incidents and adverse events with contextual needs analysis and short-term observations. Furthermore the research group is working on detailing the barriers of in situ simulation such as resources for team training despite...

  20. [Chemiluminescence spectroscopic analysis of homogeneous charge compression ignition combustion processes].

    Science.gov (United States)

    Liu, Hai-feng; Yao, Ming-fa; Jin, Chao; Zhang, Peng; Li, Zhe-ming; Zheng, Zun-qing

    2010-10-01

    To study the combustion reaction kinetics of homogeneous charge compression ignition (HCCI) under different port injection strategies and intake temperature conditions, the tests were carried out on a modified single-cylinder optical engine using chemiluminescence spectroscopic analysis. The experimental conditions are keeping the fuel mass constant; fueling the n-heptane; controlling speed at 600 r x min(-1) and inlet pressure at 0.1 MPa; controlling inlet temperature at 95 degrees C and 125 degrees C, respectively. The results of chemiluminescence spectrum show that the chemiluminescence is quite faint during low temperature heat release (LTHR), and these bands spectrum originates from formaldehyde (CH2O) chemiluminescence. During the phase of later LTHR-negative temperature coefficient (NTC)-early high temperature heat release (HTHR), these bands spectrum also originates from formaldehyde (CH2O) chemiluminescence. The CO--O* continuum is strong during HTHR, and radicals such as OH, HCO, CH and CH2O appear superimposed on this CO--O* continuum. After the HTHR, the chemiluminescence intensity is quite faint. In comparison to the start of injection (SOI) of -30 degrees ATDC, the chemiluminescence intensity is higher under the SOI = -300 degrees ATDC condition due to the more intense emissions of CO--O* continuum. And more radicals of HCO and OH are formed, which also indicates a more intense combustion reaction. Similarly, more intense CO--O* continuum and more radicals of HCO and OH are emitted under higher intake temperature case.

  1. A new combustion process with zero CO{sub 2} emission

    Energy Technology Data Exchange (ETDEWEB)

    Meijer, R. [Kema Power Generation and Sustainables, Arnheim (Netherlands)

    2003-07-01

    A new combustion process with zero carbon dioxide emissions is under investigation at KEMA Power Generation and Sustainables, an electric utility in the Netherlands. In the combustion process under consideration, there is no contact between the fuel and the combustion air. Oxygen is transferred from the air to the fuel by a reduction/oxidation mechanism with a solid intermediate. The produced flue gas has only carbon dioxide and water. After condensing, carbon dioxide is the only component left in the flue gas, and this can be readily separated without using too much energy. This combustion process, which has been referred to as Chemical Looping Combustion, can be operated at high pressure and gas expander inlet temperature. It is designed for high efficiency gas turbine cycles, has very low NOx emission and can separate CO{sub 2} without an energy penalty. The economic feasibility of this process depends on the stability of the solid material for oxygen transfer. KEMA has performed cyclic reduction-oxidation cycles with a specific catalyst under a wide range of operating conditions in a thermobalance and fluid-bed combustor to gain a better understanding of the chemistry involved in this process. This paper presents experimental test results involving NiO/AL{sub 2}O{sub 3} catalyst in combination with methane and air. 24 refs., 12 figs.

  2. In situ ellipsometric study of the three-stage process in CuInSe{sub 2} film deposition

    Energy Technology Data Exchange (ETDEWEB)

    Shirakata, Sho; Takahashi, Toshihiro; Matsunaga, Hiroaki [Faculty of Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama (Japan)

    2013-08-15

    In Situ ellipsometric study has been carried out during the deposition of the CuInSe{sub 2} thin film by means of the three-stage process. A rotator analyzing ellipsomerter using a 632.8 nm He-Ne laser was used. Ellipsometric parameters ({Psi} and {Delta}) and reflectivity R was obtained during the entire deposition stages, in which a complex reflection coefficient is {rho}=tan{Psi} exp(i{Delta}). Cu, In and Se were deposited on the Mo-coated SLG substrate. At the first-stage (In-Se deposition), the In-Se film deposition rate and its reflactive index has been obtained on the basis of the light interference. At the second-stage, changes in both {Psi} and {Delta} are observed. Based on the X-ray diffraction measurement, these changes are related to the stoichiometric composition of the film from In-rich to Cu-rich. This signal was utilized as a process switch from the second-stage to the third-stage. At the third stage, the weak change in {Psi} has been observed showing the change of the stoichiometric composition from the Cu- rich to the In-rich. By means of the in situ ellipsometry-controlled three-stage process, the CuInSe{sub 2} layer with single phase chalcopyrite structure has successfully been prepared, which exhibits an intense near-band-edge photoluminescence at 0.998 eV at room temperature. The preliminary fabricated ZnO/CdS/CuInSe{sub 2} solar cell exhibited a conversion efficiency of 5.6%. (copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  3. Process Simulation of Oxy-combustion CO2 Capture in Cement Plant

    OpenAIRE

    2014-01-01

    The objectives of this master thesis have been to model and simulate oxy-combustion CO2 capture in a cement plant. The model developed is a process simulation of the calcination process with varying degree of air in-leakage, where heat is supplied by combustion in an oxygen rich environment, followed by capture of the CO2. The further gas separation after H2O condensation to achieve the required CO2 quality was evaluated. In addition to the process simulations, a review of literature related ...

  4. Advanced Diagnostics in Oxy-Fuel Combustion Processes

    DEFF Research Database (Denmark)

    Brix, Jacob; Toftegaard, Maja Bøg; Clausen, Sønnik

    stop in place the efficacy of the FTIR probe for gas temperature determination was comparable to the use of a traditional thermocouple. The evaluation of the FTIR technique regarding estimation of gas phase concentrations of H2O, CO2 and CO showed that the method is reliable though it cannot be stated...... technique was an invaluable tool in the discussion of data obtained by gas analysis, and it allowed for estimation of combustion times in O2/CO2 where the high CO2 concentration prevents the use of the carbon mass balance for that purpose. During the project the data have been presented at a conference...... scale fixed bed reactor. The results obtained in the swirl burner have proved the FTIR method as a valuable technique for gas phase temperature measurements. When its efficacy is evaluated against traditional thermocouple measurements, two cases, with and without probe beam stop, must however be treated...

  5. Development of second-generation pressurized fluidized bed combustion process

    Energy Technology Data Exchange (ETDEWEB)

    Wolowodiuk, W.; Robertson, A. [Foster Wheeler Development Corp., Livingston, NJ (United States); Bonk, D. [Dept. of Energy, Morgantown, WV (United States)

    1995-12-01

    Under the sponsorship of the United States Department of Energy, Foster Wheeler Development Corporation, and its team members, Westinghouse, Gilbert/Commonwealth, and the Institute of Gas Technology are developing second-generation pressurized fluidized bed combustion technology capable of achieving net plant efficiency in excess of 45 percent based on the higher heating value of the coal. A three-phase program entails design and costing of a 500 MWe power plant and identification of developments needed to commercialize this technology (Phase 1), testing of individual components (Phase 2), and finally testing these components in an integrated mode (Phase 3). This paper briefly describes the results of the first two phases as well as the progress on the third phase. Since other projects which use the same technology are in construction or in negotiation stages-namely, the Power System Development Facility and the Four Rivers Energy Modernization Projects-brief descriptions of these are also included.

  6. Environmental research plan for the Geokinetics Inc. investigation of the horizontal in situ oil shale retorting process

    Energy Technology Data Exchange (ETDEWEB)

    Spradlin, H.K.L.; Hutchinson, D.L.; Mankowski, S.G.

    1979-11-30

    The development of a horizontal in-situ retorting process may have significant impacts upon valuable environmental resources. A research program has been developed to identify, assess, and minimize the adverse environmental impacts which may result. The goals are to: describe the environment as it existed prior to disturbance; determine the nature and extent of the changes; develop and implement measures to minimize the adverse impacts; develop and implement reclamation procedures which will return the affected land to its original level; and coordinate measures to protect the health and safety of persons and animals which may be affected by the activities. Specific research areas are outlined. These include atmospheric, hydrologic, terrestrial ecology, and social/economic research. (DMC)

  7. In situ synthesis of magnetic mesoporous silica via sol-gel process coupled with precipitation and oxidation

    Institute of Scientific and Technical Information of China (English)

    Junqi Zhao; Yujun Wang; Guangsheng Luo; Shenlin Zhu

    2011-01-01

    A novel method was proposed for the in situ synthesis of magnetite-containing mesoporous silica SBA-16 via a sol-gel process coupled with precipitation and oxidation. The effect of the added amounts of reactants on the mesostructural and magnetic properties of the magnetic mesoporous silica was investigated. It was determined that the synthesized magnetic mesoporous silica with a total pore volume of 0.64-0.96 cm3/g and an average pore diameter of 4.0-14.9 nm had a relatively high saturation magnetization value (1.11-5.77 emu/g) and a large surface area (258-747 m2/g). Lysozyme was chosen as a model protein to test the performance of the magnetic mesoporous silica as a protein adsorbent. The high adsorption capacity (up to 212 mg/g) suggested a promising future as bimolecular hosts for the magnetic mesoporous silica.

  8. Effects of Catalysts on Emissions of Pollutants from Combustion Processes of Liquid Fuels

    Science.gov (United States)

    Bok, Agnieszka; Guziałowska-Tic, Joanna; Tic, Wilhelm Jan

    2014-12-01

    The dynamic growth of the use of non-renewable fuels for energy purposes results in demand for catalysts to improve their combustion process. The paper describes catalysts used mainly in the processes of combustion of motor fuels and fuel oils. These catalysts make it possible to raise the efficiency of oxidation processes simultanously reducing the emission of pollutants. The key to success is the selection of catalyst compounds that will reduce harmful emissions of combustion products into the atmosphere. Catalysts are introduced into the combustion zone in form of solutions miscible with fuel or with air supplied to the combustion process. The following compounds soluble in fuel are inclused in the composition of the described catalysts: organometallic complexes, manganese compounds, salts originated from organic acids, ferrocen and its derivatives and sodium chloride and magnesium chloride responsible for burning the soot (chlorides). The priority is to minimize emissions of volatile organic compounds, nitrogen oxides, sulphur oxides, and carbon monoxide, as well as particulate matter.

  9. Control strategies for CAI combustion processes; Strategien zur Regelung von CAI-Brennverfahren

    Energy Technology Data Exchange (ETDEWEB)

    Karrelmeyer, R.; Graf, G.; Scherrer, D.; Fischer, W.; Hathout, J.P. [Robert Bosch GmbH, Stuttgart (Germany)

    2008-07-01

    The contribution presents concepts for control of a CAI combustion process with internal exhaust trapping. The concepts are based on combustion characteristics obtained from the combustion chamber pressure signal. Combustion is controlled using the control variables of the air and fuel systems. The engines investigated were engines with variable valve drive, with different degrees of variability, and with a direct injection system. In a first step, a fully variable valve control system is investigated which enables adjustment of the gas change valves for the individual cylinders. In the second step, the cost aspect is considered and a control strategy is presented which does not control individual cylinders but uses a valve control strategy with conventional phase control elements. The control concepts presented here are a combination of pre-control and combustion characteristics control. Results obtained during operating mode switching, dynamic operation and stabilisation of the CAI mode are presented as well. Pre-control is particularly important in order to prevent misfires as well as extremely early and loud combustion both in dynamic operation and during switching. (orig.)

  10. Experimental simulation and numerical analysis of coal spontaneous combustion process at low temperature

    Institute of Scientific and Technical Information of China (English)

    文虎; 徐精彩; 葛岭梅

    2001-01-01

    The characteristic of coal spontaneous, combustion includes oxidative property and exothermic capacity. It can really simulate the process of coal spontaneous combustion to use the large-scale experimental unit loading coal ! 000 kg. According to the field change of gas concentration and coal temperature determined through experiment of coal self-ignite at low temperature stage, and on the basis of hydromechanics and heat-transfer theory, some parameters can be calculated at different low temperature stage, such as, oxygen consumption rate, heat liberation intensity. It offers a theoretic criterion for quantitatively analyzing characteristic of coal self-ignite and forecasting coal spontaneous combustion. According to coal exothermic capability and its thermal storage surroundings, thermal equilibrium is applied to deduce the computational method of limit parameter of coal self-ignite. It offers a quantitative theoretic criterion for coal self-ignite forecasting and preventing. According to the measurement and test of spontaneous combustion of Haibei coal, some token parameter of Haibei coal,spontaneous combustion is quantitatively analyzed, such as, spontaneous combustion period of coal, critical temperature, oxygen consumption rate, heat liberation intensity, and limit parameter of coal self-ignite.

  11. Experimental simulation and numerical analysis of coal spontaneous combustion process at low temperature*

    Institute of Scientific and Technical Information of China (English)

    WEN Hu; XU Jing-cai; GE Ling-mei

    2001-01-01

    The characteristic of coal spontaneous combustion includes oxidative p roperty and exothermic capacity. It can really simulate the process of coal spon taneous combustion to use the large-scale experimental unit loading coal 1 000 kg. According to the field change of gas concentration and coal temperature determi ned through experiment of coal self-ignite at low temperature stage, and on the basis of hydromechanics and heat-transfer theory, some parameters can be calcul at ed at different low temperature stage, such as, oxygen consumption rate, heat li beration intensity. It offers a theoretic criterion for quantitatively analyzing characteristic of coal self-ignite and forecasting coal spontaneous combustion . According to coal exothermic capability and its thermal storage surroundings, t hermal equilibrium is applied to deduce the computational method of limit parame ter of coal self-ignite. It offers a quantitative theoretic criterion for coal s elf-ignite forecasting and preventing. According to the measurement and test of spontaneous combustion of Haibei coal, some token parameter of Haibei coal spont aneous combustion is quantitatively analyzed, such as, spontaneous combustion pe riod of coal, critical temperature, oxygen consumption rate, heat liberation int ensity, and limit parameter of coal self-ignite.

  12. Efficient volatile metal removal from low rank coal in gasification, combustion, and processing systems and methods

    Energy Technology Data Exchange (ETDEWEB)

    Bland, Alan E.; Sellakumar, Kumar Muthusami; Newcomer, Jesse D.

    2017-03-21

    Efficient coal pre-processing systems (69) integrated with gasification, oxy-combustion, and power plant systems include a drying chamber (28), a volatile metal removal chamber (30), recirculated gases, including recycled carbon dioxide (21), nitrogen (6), and gaseous exhaust (60) for increasing the efficiencies and lowering emissions in various coal processing systems.

  13. Efficient volatile metal removal from low rank coal in gasification, combustion, and processing systems and methods

    Science.gov (United States)

    Bland, Alan E.; Sellakumar, Kumar Muthusami; Newcomer, Jesse D.

    2017-03-21

    Efficient coal pre-processing systems (69) integrated with gasification, oxy-combustion, and power plant systems include a drying chamber (28), a volatile metal removal chamber (30), recirculated gases, including recycled carbon dioxide (21), nitrogen (6), and gaseous exhaust (60) for increasing the efficiencies and lowering emissions in various coal processing systems.

  14. In situ visualization of the electrolyte solvent filling process by neutron radiography

    Science.gov (United States)

    Knoche, Thomas; Zinth, Veronika; Schulz, Michael; Schnell, Joscha; Gilles, Ralph; Reinhart, Gunther

    2016-11-01

    In the manufacturing of Li-ion battery cells, filling with electrolyte liquid is a crucial step in terms of product quality and cost. To gain insight into the process phenomena, a non-destructive imaging method is presented. It is shown that the spreading of electrolyte liquid within the cell during filling and wetting can be visualized by neutron radiography. The experiment allows for the first time to visualize the soaking behaviour of electrolyte liquid in battery cells. The influence of the process parameters on the wetting behaviour is studied and flow paths of the liquid are identified. The electrolyte intake into the cell stack is discussed with two different analytical approaches. Based on the experimental data, the production process can be optimized, leading to stable cell performance and cost reduction due to faster processes and lower scrap rates.

  15. Focused beam reflectance measurement as a tool for in situ monitoring of the lactose crystallization process

    National Research Council Canada - National Science Library

    Pandalaneni, K; Amamcharla, J K

    2016-01-01

    .... Production of lactose is usually carried out by a process called crystallization. Several factors including rate of cooling, presence of impurities, and mixing speed influence the crystal size characteristics...

  16. Numerical methods application to study processes in the CFB boilers combustion chambers

    Directory of Open Access Journals (Sweden)

    Koksharev Oleg M.

    2017-01-01

    Full Text Available This paper presents the application of numerical calculation of a hybrid Euler–Lagrange approach to model the gas–solid flow combined with a combustion process in the CFB boiler that has been resolved by applying the ANSYS FLUENT 14.0. In this work, the numerical modelling of furnace processes at various speeds of airflow supply from below was estimated. For the design speed adopted values of 0.5, 1.5, 2.5 and 5 m/s. The research object is the combustion chamber of boiler unit with CFB, with steam capacity of 230 t/h.

  17. Numerical methods application to study processes in the CFB boilers combustion chambers

    OpenAIRE

    Koksharev Oleg M.; Gil Andrey V.

    2017-01-01

    This paper presents the application of numerical calculation of a hybrid Euler–Lagrange approach to model the gas–solid flow combined with a combustion process in the CFB boiler that has been resolved by applying the ANSYS FLUENT 14.0. In this work, the numerical modelling of furnace processes at various speeds of airflow supply from below was estimated. For the design speed adopted values of 0.5, 1.5, 2.5 and 5 m/s. The research object is the combustion chamber of boiler unit with CFB, with ...

  18. In-Situ Real Time Monitoring and Control of Mold Making and Filling Processes: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed Abdelrahman; Kenneth Currie

    2010-12-22

    This project presents a model for addressing several objectives envisioned by the metal casting industries through the integration of research and educational components. It provides an innovative approach to introduce technologies for real time characterization of sand molds, lost foam patterns and monitoring of the mold filling process. The technology developed will enable better control over the casting process. It is expected to reduce scrap and variance in the casting quality. A strong educational component is integrated into the research plan to utilize increased awareness of the industry professional, the potential benefits of the developed technology, and the potential benefits of cross cutting technologies.

  19. Process/Engineering Co-Simulation of Oxy-Combustion and Chemical Looping Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Sloan, David [Alstom Power Inc., Windsor, CT (United States)

    2013-03-01

    Over the past several years, the DOE has sponsored various funded programs, collectively referred to as Advanced Process Engineering Co-Simulator (APECS) programs, which have targeted the development of a steady-state simulator for advanced power plants. The simulator allows the DOE and its contractors to systematically evaluate various power plant concepts, either for preliminary conceptual design or detailed final design.

  20. Converting oil shale to liquid fuels: energy inputs and greenhouse gas emissions of the Shell in situ conversion process.

    Science.gov (United States)

    Brandt, Adam R

    2008-10-01

    Oil shale is a sedimentary rock that contains kerogen, a fossil organic material. Kerogen can be heated to produce oil and gas (retorted). This has traditionally been a CO2-intensive process. In this paper, the Shell in situ conversion process (ICP), which is a novel method of retorting oil shale in place, is analyzed. The ICP utilizes electricity to heat the underground shale over a period of 2 years. Hydrocarbons are produced using conventional oil production techniques, leaving shale oil coke within the formation. The energy inputs and outputs from the ICP, as applied to oil shales of the Green River formation, are modeled. Using these energy inputs, the greenhouse gas (GHG) emissions from the ICP are calculated and are compared to emissions from conventional petroleum. Energy outputs (as refined liquid fuel) are 1.2-1.6 times greater than the total primary energy inputs to the process. In the absence of capturing CO2 generated from electricity produced to fuel the process, well-to-pump GHG emissions are in the range of 30.6-37.1 grams of carbon equivalent per megajoule of liquid fuel produced. These full-fuel-cycle emissions are 21%-47% larger than those from conventionally produced petroleum-based fuels.

  1. In-situ product removal from fermentations by membrane extraction: conceptual process design and economics

    NARCIS (Netherlands)

    Heerema, L.; Roelands, C.P.M.; Goetheer, E.L.V.; Verdoes, D.; Keurentjes, J.

    2011-01-01

    This paper describes a conceptual process design for the production of the model component phenol by a recombinant strain of the micro-organism Pseudomonas putida S12. The (bio)production of the inhibiting component phenol in a bioreactor is combined with direct product removal by membrane extractio

  2. In situ diagnostics of the crystal-growth process through neutron imaging

    DEFF Research Database (Denmark)

    Tremsin, Anton S.; Makowska, Malgorzata Grazyna; Perrodin, Didier

    2016-01-01

    Neutrons are known to be unique probes in situations where other types of radiation fail to penetrate samples and their surrounding structures. In this paper it is demonstrated how thermal and cold neutron radiography can provide time-resolved imaging of materials while they are being processed (e......, as limited by the resolution of the present experiments). It is also demonstrated that the dopant concentration can be quantified even for very low concentration levels (∼ 0.1%) in 10 mm thick samples. The interface between the solid and liquid phases can also be imaged, provided there is a sufficient change.......g. while growing single crystals). The processing equipment, in this case furnaces, and the scintillator materials are opaque to conventional X-ray interrogation techniques. The distribution of the europium activator within a BaBrCl:Eu scintillator (0.1 and 0.5% nominal doping concentrations per mole...

  3. Deliquescence and Efflorescence Processes of Aerosol Particles Studied by in situ FTIR and Raman Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    Li-jun Zhao; Feng Wang; Kun Zhang; Qing-xuan Zeng; Yun-hong Zhang

    2008-01-01

    Deliquescence and efflorescence are the two most important physicochemical processes of aerosol particles.In deliquescence and efflorescence cycles of aerosol particles,many fundamental problems need to be investigated in detail on the molecular level,including ion and molecule interactions in supersaturated aerosols,metastable solid phases that may be formed,and microscopic structures and deliquescence mechanisms of aerosol particles.This paper presents a summary of the progress made in recent investigations of deliquescence and efflorescence processes of aerosol particles by four common spectral techniques,which are known as Raman/electrodynamic balance,Fourier transform infrared/aerosol flow tube,Fourier transform infrared/attenuated total reflection,and confocal Raman on a quartz substrate.

  4. [Real time diagnostics of instantaneous temperature of combustion and explosion process by modern spectroscopy].

    Science.gov (United States)

    Zhou, Xue-tie; Wang, Jun-de; Li, Yan; Liu, Da-bing

    2003-04-01

    The combustion temperature is one of the important parameters to express flame combustion and explosion characteristics. It will effectively guide the design and manufacture of new model explosives, industrial explosive materials, and weapons. The recent developments and applications of real time diagnostics of instantaneous temperature of combustion and explosion processes by modern spectroscopic methods, such as atomic absorption-emission method, atomic emission two-line spectroscopy, atomic emission multiline spectroscopy, molecular rotation-vibration spectroscopy, coherent anti-stokes Raman scattering (CARS) and plane laser-induced fluorescence (PLIF), were reviewed in this paper. The maximum time resolution of atomic absorption-emission method is 25 microseconds. The time resolution of atomic emission two-line spectroscopy can reach 0.1 microsecond. These two methods can completely suit the need of real time and instantaneous temperature diagnostics of violent explosion and flame combustion. Other methods will also provide new effective research methods for the processes and characteristics of combustion, flame and explosion.

  5. In-situ Monitoring of Dynamic Phenomena during Solidification and Phase Transformation Processing

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, Amy J. [Los Alamos National Laboratory; Cooley, Jason C. [Los Alamos National Laboratory; Morris, Christopher [Los Alamos National Laboratory; Merrill, Frank E. [Los Alamos National Laboratory; Hollander, Brian J. [Los Alamos National Laboratory; Mariam, Fesseha G. [Los Alamos National Laboratory; Patterson, Brian M. [Los Alamos National Laboratory; Imhoff, Seth D. [Los Alamos National Laboratory; Lee, Wah Keat [Brookhaven National Lab; Fezzaa, Kamel [Argonne National Lab; Deriy, Alex [Argonne NationalLbaoratory; Tucker, Tim J. [Los Alamos National Laboratory; Clarke, Kester D. [Los Alamos National Laboratory; Field, Robert D. [Los Alamos National Laboratory; Thoma, Dan J. [Los Alamos National Laboratory; Teter, David F. [Los Alamos National Laboratory; Beard, Timothy V. [Los Alamos National Laboratory; Hudson, Richard W. [Los Alamos National Laboratory; Freibert, Franz J. [Los Alamos National Laboratory; Korzekwa, Deniece R. [Los Alamos National Laboratory; Farrow, Adam M. [Los Alamos National Laboratory; Cross, Carl E. [Los Alamos National Laboratory; Mihaila, Bogdan [Los Alamos National Laboratory; Lookman, Turab [Los Alamos National Laboratory; Hunter, Abigail [Los Alamos National Laboratory; Choudhury, Samrat [Los Alamos National Laboratory; Karma, Alain [Northeastern University; Ott, Thomas J. Jr. [Los Alamos National Laboratory; Barker, Martha R. [Los Alamos National Laboratory; O' Neill, Finian [Former MST-6 Summer Student; Hill, Joshua [Former MST-6 Summer Student; Emigh, Megan G. [Los Alamos National Laboratory

    2012-07-30

    The purpose of this project is to: (1) Directly observe phase transformations and microstructure evolution using proton (and synchrotron x-ray) radiography and tomography; (2) Constrain phase-field models for microstructure evolution; (3) Experimentally control microstructure evolution during processing to enable co-design; and (4) Advance toward the MaRIE vision. Understand microstructure evolution and chemical segregation during solidification {yields} solid-state transformations in Pu-Ga.

  6. Characterization of boron carbide particulate reinforced in situ copper surface composites synthesized using friction stir processing

    Energy Technology Data Exchange (ETDEWEB)

    Sathiskumar, R., E-mail: sathiscit2011@gmail.com [Department of Mechanical Engineering, Coimbatore Institute of Technology, Coimbatore, 641 014 Tamil Nadu (India); Murugan, N., E-mail: murugan@cit.edu.in [Department of Mechanical Engineering, Coimbatore Institute of Technology, Coimbatore, 641 014 Tamil Nadu (India); Dinaharan, I., E-mail: dinaweld2009@gmail.com [Department of Mechanical Engineering, V V College of Engineering, Tisaiyanvilai, 627 657 Tamil Nadu (India); Vijay, S.J., E-mail: vijayjoseph@karunya.edu [Centre for Research in Metallurgy (CRM), School of Mechanical Sciences, Karunya University, Coimbatore, 641 114 Tamil Nadu (India)

    2013-10-15

    Friction stir processing has evolved as a novel solid state technique to fabricate surface composites. The objective of this work is to apply the friction stir processing technique to fabricate boron carbide particulate reinforced copper surface composites and investigate the effect of B{sub 4}C particles and its volume fraction on microstructure and sliding wear behavior of the same. A groove was prepared on 6 mm thick copper plates and packed with B{sub 4}C particles. The dimensions of the groove was varied to result in five different volume fractions of B{sub 4}C particles (0, 6, 12, 18 and 24 vol.%). A single pass friction stir processing was done using a tool rotational speed of 1000 rpm, travel speed of 40 mm/min and an axial force of 10 kN. Metallurgical characterization of the Cu/B{sub 4}C surface composites was carried out using optical microscope and scanning electron microscope. The sliding wear behavior was evaluated using a pin-on-disk apparatus. Results indicated that the B{sub 4}C particles significantly influenced the area, dispersion, grain size, microhardness and sliding wear behavior of the Cu/B{sub 4}C surface composites. When the volume fraction of B{sub 4}C was increased, the wear mode changed from microcutting to abrasive wear and wear debris was found to be finer. Highlights: • Fabrication of Cu/B{sub 4}C surface composite by friction stir processing • Analyzing the effect of B{sub 4}C particles on the properties of Cu/B4C surface composite • Increased volume fraction of B{sub 4}C particles reduced the area of surface composite. • Increased volume fraction of B{sub 4}C particles enhanced the microhardness and wear rate. • B{sub 4}C particles altered the wear mode from microcutting to abrasive.

  7. In-situ examination of diffusion and precipitation processes during the evolution of chemical garden systems

    OpenAIRE

    Glaab, Fabian

    2012-01-01

    “Chemical” or “silicate gardens” are a well known example for the spontaneous formation of a complex and structured system from ordinary educts. Simply by addition of soluble metal salt crystals to alkaline silica sols, dissolution of the metal salt and subsequent solidification initiate a self-organization process, which not only produces two separated compartments with drastically different chemical conditions by precipitation of a closed and tubular membrane but also produces a variety of ...

  8. In situ imaging and height reconstruction of phase separation processes in polymer blends during spin coating.

    Science.gov (United States)

    Ebbens, Stephen; Hodgkinson, Richard; Parnell, Andrew J; Dunbar, Alan; Martin, Simon J; Topham, Paul D; Clarke, Nigel; Howse, Jonathan R

    2011-06-28

    Spin coating polymer blend thin films provides a method to produce multiphase functional layers of high uniformity covering large surface areas. Applications for such layers include photovoltaics and light-emitting diodes where performance relies upon the nanoscale phase separation morphology of the spun film. Furthermore, at micrometer scales, phase separation provides a route to produce self-organized structures for templating applications. Understanding the factors that determine the final phase-separated morphology in these systems is consequently an important goal. However, it has to date proved problematic to fully test theoretical models for phase separation during spin coating, due to the high spin speeds, which has limited the spatial resolution of experimental data obtained during the coating process. Without this fundamental understanding, production of optimized micro- and nanoscale structures is hampered. Here, we have employed synchronized stroboscopic illumination together with the high light gathering sensitivity of an electron-multiplying charge-coupled device camera to optically observe structure evolution in such blends during spin coating. Furthermore the use of monochromatic illumination has allowed interference reconstruction of three-dimensional topographies of the spin-coated film as it dries and phase separates with nanometer precision. We have used this new method to directly observe the phase separation process during spinning for a polymer blend (PS-PI) for the first time, providing new insights into the spin-coating process and opening up a route to understand and control phase separation structures.

  9. Blendas PVC/NBR por processamento reativo I: desenvolvimento do processo de vulcanização Dinâmica in situ PVC/NBR blends by reactive processing I: in situ dynamic vulcanization process

    Directory of Open Access Journals (Sweden)

    Fábio R. Passador

    2007-06-01

    Full Text Available Vulcanização dinâmica é o processo de vulcanização de um elastômero durante a mistura no estado fundido com um termoplástico, que resulta em uma classe de materiais denominada termoplásticos vulcanizados. Neste trabalho, um novo tipo de termoplástico vulcanizado foi obtido por vulcanização dinâmica in situ da blenda PVC/NBR, utilizando-se um sistema de cura a base de enxofre (S e combinação dos aceleradores 2,2-ditiomercaptobenzotiazol (MBTS e dissulfeto de tetrametiltiuram (TMTD. As blendas PVC/NBR (90/10, 80/20 e 70/30% em massa foram processadas em um reômetro de torque Haake (Rheomix 600 a 160 °C com rotação de 60 rpm. As blendas obtidas por processamento reativo foram caracterizadas por calorimetria diferencial de varredura (DSC para determinação do grau de cura. Observou-se aumento no grau de cura das blendas com o tempo de mistura sendo o sistema de cura considerado eficiente.Dynamic vulcanization is a process of vulcanization of an elastomer during melt mixing with a thermoplastic wich results in material called thermoplastic vulcanizates or TPVs. In this study, a new kind of TPV was obtained by in situ dynamic curing of poly(vinyl chloride (PVC/nitrile rubber (NBR blends. The crosslinking of PVC/NBR blends was accomplished using sulphur (S/tetramethylthiuram disulphide (TMTD and mercaptobenzthiazyl disulphide (MBTS curative system during the reactive processing. The blends of PVC/NBR at the ratio of 90/10; 80/20 and 70/30 wt. (% were melt mixed using a Haake Rheomix 600 at 160 °C and rotor speed of 60 rpm. The curing behavior of NBR was investigated by a Monsanto Rheometer and the degree of cure was calculated using differential scanning calorimetry (DSC for different mixing times. It was observed that the degree of cure increases with the mixing time and the crosslinking system used in this work was considered efficient.

  10. In Situ Detection of Strong Langmuir Turbulence Processes in Solar Type III Radio Bursts

    Science.gov (United States)

    Golla, Thejappa; Macdowall, Robert J.; Bergamo, M.

    2012-01-01

    The high time resolution observations obtained by the WAVES experiment of the STEREO spacecraft in solar type III radio bursts show that Langmuir waves often occur as intense localized wave packets. These wave packets are characterized by short durations of only a few ms and peak intensities, which well exceed the supersonic modulational instability (MI) thresholds. These timescales and peak intensities satisfy the criterion of the solitons collapsed to spatial scales of a few hundred Debye lengths. The spectra of these wave packets consist of primary spectral peaks corresponding to beam-resonant Langmuir waves, two or more sidebands corresponding to down-shifted and up-shifted daughter Langmuir waves, and low frequency enhancements below a few hundred Hz corresponding to daughter ion sound waves. The frequencies and wave numbers of these spectral components satisfy the resonance conditions of the modulational instability (MI). Moreover, the tricoherences, computed using trispectral analysis techniques show that these spectral components are coupled to each other with a high degree of coherency as expected of the MI type of four wave interactions. The high intensities, short scale lengths, sideband spectral structures and low frequency spectral enhancements and, high levels of tricoherences amongst the spectral components of these wave packets provide unambiguous evidence for the supersonic MI and related strong turbulence processes in type III radio bursts. The implication of these observations include: (1) the MI and related strong turbulence processes often occur in type III source regions, (2) the strong turbulence processes probably play very important roles in beam stabilization as well as conversion of Langmuir waves into escaping radiation at the fundamental and second harmonic of the electron plasma frequency, fpe, and (3) the Langmuir collapse probably follows the route of MI in type III radio bursts.

  11. Synthesis of magnetic tunnel junctions with full in situ atomic layer and chemical vapor deposition processes

    Energy Technology Data Exchange (ETDEWEB)

    Mantovan, R., E-mail: roberto.mantovan@mdm.imm.cnr.it [Laboratorio MDM, IMM-CNR, Via C. Olivetti 2, 20864 Agrate Brianza (Italy); Vangelista, S.; Kutrzeba-Kotowska, B.; Cocco, S.; Lamperti, A.; Tallarida, G. [Laboratorio MDM, IMM-CNR, Via C. Olivetti 2, 20864 Agrate Brianza (MB) (Italy); Mameli, D. [Laboratorio MDM, IMM-CNR, Via C. Olivetti 2, 20864 Agrate Brianza (Italy); Dipartimento di Scienze Chimiche, Universita di Cagliari, Cittadella Universitaria, 09042 Monserrato, Cagliari (Italy); Fanciulli, M. [Laboratorio MDM, IMM-CNR, Via C. Olivetti 2, 20864 Agrate Brianza (Italy); Dipartimento di Scienza dei Materiali, Universita degli studi Milano-Bicocca, Via R Cozzi 53, 20125 Milano (Italy)

    2012-05-01

    Magnetic tunnel junctions, i.e. the combination of two ferromagnetic electrodes separated by an ultrathin tunnel oxide barrier, are core elements in a large variety of spin-based devices. We report on the use of combined chemical vapor and atomic layer deposition processes for the synthesis of magnetic tunnel junctions with no vacuum break. Structural, chemical and morphological characterizations of selected ferromagnetic and oxide layers are reported, together with the evidence of tunnel magnetoresistance effect in patterned Fe/MgO/Co junctions.

  12. A simple process for the fabrication of large-area CVD graphene based devices via selective in situ functionalization and patterning

    Science.gov (United States)

    Alexeev, Arseny M.; Barnes, Matthew D.; Karthik Nagareddy, V.; Craciun, Monica F.; Wright, C. David

    2017-03-01

    We report a novel approach for the fabrication of micro- and nano-scale graphene devices via the in situ plasma functionalization and in situ lithographic patterning of large-area graphene directly on CVD catalytic metal (Cu) substrates. This enables us to create graphene-based devices in their entirety prior to any transfer processes, simplifying very significantly the device fabrication process and potentially opening up the route to the use of a wider range of target substrates. We demonstrate the capabilities of our technique via the fabrication of a flexible, transparent, graphene/graphene oxide humidity sensor that outperforms a conventional commercial sensor.

  13. Endoscopic fringe projection for in-situ inspection of a sheet-bulk metal forming process

    Science.gov (United States)

    Matthias, Steffen; Kästner, Markus; Reithmeier, Eduard

    2015-05-01

    Sheet-bulk metal forming is a new production process capable of performing deep-drawing and massive forming steps in a single operation. However, due to the high forming forces of the forming process, continuous process control is required in order to detect wear on the forming tool before production quality is impacted. To be able to measure the geometry of the forming tool in the limited space of forming presses, a new inspection system is being developed within the SFB/TR 73 collaborative research center. In addition to the limited space, the process restricts the amount of time available for inspection. Existing areal optical measurement systems suffer from shadowing when measuring the tool's inner elements, as they cannot be placed in the limited space next to the tool, while tactile measurement systems cannot meet the time restrictions for measuring the areal geometries. The new inspection system uses the fringe projection optical measurement principle to capture areal geometry data from relevant parts of the forming tool in short time. Highresolution image fibers are used to connect the system's compact sensor head to a base unit containing both camera and projector of the fringe projection system, which can be positioned outside of the moving parts of the press. To enable short measurement times, a high intensity laser source is used in the projector in combination with a digital micro-mirror device. Gradient index lenses are featured in the sensor head to allow for a very compact design that can be used in the narrow space above the forming tool inside the press. The sensor head is attached to an extended arm, which also guides the image fibers to the base unit. A rotation stage offers the possibility to capture measurements of different functional elements on the circular forming tool by changing the orientation of the sensor head next to the forming tool. During operation of the press, the arm can be travelled out of the moving parts of the forming press

  14. IN-SITU IONIC CHEMICAL ANALYSIS OF FRESH WATER VIA A NOVEL COMBINED MULTI-SENSOR / SIGNAL PROCESSING ARCHITECTURE

    Science.gov (United States)

    Mueller, A. V.; Hemond, H.

    2009-12-01

    The capability for comprehensive, real-time, in-situ characterization of the chemical constituents of natural waters is a powerful tool for the advancement of the ecological and geochemical sciences, e.g. by facilitating rapid high-resolution adaptive sampling campaigns and avoiding the potential errors and high costs related to traditional grab sample collection, transportation and analysis. Portable field-ready instrumentation also promotes the goals of large-scale monitoring networks, such as CUASHI and WATERS, without the financial and human resources overhead required for traditional sampling at this scale. Problems of environmental remediation and monitoring of industrial waste waters would additionally benefit from such instrumental capacity. In-situ measurement of all major ions contributing to the charge makeup of natural fresh water is thus pursued via a combined multi-sensor/multivariate signal processing architecture. The instrument is based primarily on commercial electrochemical sensors, e.g. ion selective electrodes (ISEs) and ion selective field-effect transistors (ISFETs), to promote low cost as well as easy maintenance and reproduction,. The system employs a novel architecture of multivariate signal processing to extract accurate information from in-situ data streams via an "unmixing" process that accounts for sensor non-linearities at low concentrations, as well as sensor cross-reactivities. Conductivity, charge neutrality and temperature are applied as additional mathematical constraints on the chemical state of the system. Including such non-ionic information assists in obtaining accurate and useful calibrations even in the non-linear portion of the sensor response curves, and measurements can be made without the traditionally-required standard additions or ionic strength adjustment. Initial work demonstrates the effectiveness of this methodology at predicting inorganic cations (Na+, NH4+, H+, Ca2+, and K+) in a simplified system containing

  15. Microbial fuel cell based biosensor for in situ monitoring of anaerobic digestion process.

    Science.gov (United States)

    Liu, Zhidan; Liu, Jing; Zhang, Songping; Xing, Xin-Hui; Su, Zhiguo

    2011-11-01

    A wall-jet microbial fuel cell (MFC) was developed for the monitoring of anaerobic digestion (AD). This biofilm based MFC biosensor had a character of being portable, short hydraulic retention time (HRT) for sample flow through and convenient for continuous operation. The MFC was installed in the recirculation loop of an upflow anaerobic fixed-bed (UAFB) reactor in bench-scale where pH of the fermentation broth and biogas flow were monitored in real time. External disturbances to the AD were added on purpose by changing feedstock concentration, as well as process configuration. MFC signals had good correlations with online measurements (i.e. pH, gas flow rate) and offline analysis (i.e. COD) over 6-month operation. These results suggest that the MFC signal can reflect the dynamic variation of AD and can potentially be a valuable tool for monitoring and control of bioprocess.

  16. Using in-situ polymerization of conductive polymers to enhance the electrical properties of solution-processed carbon nanotube films and fibers.

    Science.gov (United States)

    Allen, Ranulfo; Pan, Lijia; Fuller, Gerald G; Bao, Zhenan

    2014-07-09

    Single-walled carbon nanotubes/polymer composites typically have limited conductivity due to a low concentration of nanotubes and the insulating nature of the polymers used. Here we combined a method to align carbon nanotubes with in-situ polymerization of conductive polymer to form composite films and fibers. Use of the conducting polymer raised the conductivity of the films by 2 orders of magnitude. On the other hand, CNT fiber formation was made possible with in-situ polymerization to provide more mechanical support to the CNTs from the formed conducting polymer. The carbon nanotube/conductive polymer composite films and fibers had conductivities of 3300 and 170 S/cm, respectively. The relatively high conductivities were attributed to the polymerization process, which doped both the SWNTs and the polymer. In-situ polymerization can be a promising solution-processable method to enhance the conductivity of carbon nanotube films and fibers.

  17. Evaluation of meat and bone meal combustion residue as lead immobilizing material for in situ remediation of polluted aqueous solutions and soils: "chemical and ecotoxicological studies".

    Science.gov (United States)

    Deydier, E; Guilet, R; Cren, S; Pereas, V; Mouchet, F; Gauthier, L

    2007-07-19

    As a result of bovine spongiform encephalopathy (BSE) crisis, meat and bone meal (MBM) production can no longer be used to feed cattle and must be safely disposed of or transformed. MBM specific incineration remains an alternative that could offer the opportunity to achieve both thermal valorization and solid waste recovery as ashes are calcium phosphate-rich material. The aim of this work is to evaluate ashes efficiency for in situ remediation of lead-contaminated aqueous solutions and soils, and to assess the bioavailability of lead using two biological models, amphibian Xenopus laevis larvae and Nicotiana tabaccum tobacco plant. With the amphibian model, no toxic or genotoxic effects of ashes are observed with concentrations from 0.1 to 5 g of ashes/L. If toxic and genotoxic effects of lead appear at concentration higher than 1 mg Pb/L (1 ppm), addition of only 100 mg of ashes/L neutralizes lead toxicity even with lead concentration up to 10 ppm. Chemical investigations (kinetics and X-ray diffraction (XRD) analysis) reveals that lead is quickly immobilized as pyromorphite [Pb10(PO4)6(OH)2] and lead carbonate dihydrate [PbCO(3).2H2O]. Tobacco experiments are realized on contaminated soils with 50, 100, 2000 and 10000 ppm of lead with and without ashes amendment (35.3g ashes/kg of soil). Tobacco measurements show that plant elongation is bigger in an ashes-amended soil contaminated with 10000 ppm of lead than on the reference soil alone. Tobacco model points out that ashes present two beneficial actions as they do not only neutralize lead toxicity but also act as a fertilizer.

  18. Waste plastics as supplemental fuel in the blast furnace process: improving combustion efficiencies.

    Science.gov (United States)

    Kim, Dongsu; Shin, Sunghye; Sohn, Seungman; Choi, Jinshik; Ban, Bongchan

    2002-10-14

    The possibility of using waste plastics as a source of secondary fuel in a blast furnace has been of recent interest. The success of this process, however, will be critically dependent upon the optimization of operating systems. For instance, the supply of waste plastics must be reliable as well as economically attractive compared with conventional secondary fuels such as heavy oil, natural gas and pulverized coal. In this work, we put special importance on the improvement of the combustibility of waste plastics as a way to enhance energy efficiency in a blast furnace. As experimental variables to approach this target, the effects of plastic particle size, blast temperature, and the level of oxygen enrichment were investigated using a custom-made blast model designed to simulate a real furnace. Lastly, the combustion efficiency of the mixture of waste plastics and pulverized coal was tested. The observations made from these experiments led us to the conclusion that with the increase of both blast temperature and the level of oxygen enrichment, and with a decrease in particle size, the combustibility of waste polyethylene could be improved at a given distance from the tuyere. Also it was found that the efficiency of coal combustion decreased with the addition of plastics; however, the combustion efficiency of mixture could be comparable at a longer distance from the tuyere.

  19. Nongray-gas Effects in Modeling of Large-scale Oxy-fuel Combustion Processes

    DEFF Research Database (Denmark)

    Yin, Chungen

    2012-01-01

    , among which radiative heat transfer under oxy-fuel conditions is one of the fundamental issues. This paper demonstrates the nongray-gas effects in modeling of large-scale oxy-fuel combustion processes. Oxy-fuel combustion of natural gas in a large-scale utility boiler is numerically investigated...... cases. The simulation results show that the gray and non-gray calculations of the same oxy-fuel WSGGM make distinctly different predictions in the wall radiative heat transfer, incident radiative flux, radiative source, gas temperature and species profiles. In relative to the non-gray implementation...

  20. A new highly automated sputter equipment for in situ investigation of deposition processes with synchrotron radiation

    Science.gov (United States)

    Döhrmann, Ralph; Botta, Stephan; Buffet, Adeline; Santoro, Gonzalo; Schlage, Kai; Schwartzkopf, Matthias; Bommel, Sebastian; Risch, Johannes F. H.; Mannweiler, Roman; Brunner, Simon; Metwalli, Ezzeldin; Müller-Buschbaum, Peter; Roth, Stephan V.

    2013-04-01

    HASE (Highly Automated Sputter Equipment) is a new mobile setup developed to investigate deposition processes with synchrotron radiation. HASE is based on an ultra-high vacuum sputter deposition chamber equipped with an in-vacuum sample pick-and-place robot. This enables a fast and reliable sample change without breaking the vacuum conditions and helps to save valuable measurement time, which is required for experiments at synchrotron sources like PETRA III at DESY. An advantageous arrangement of several sputter guns, mounted on a rotative flange, gives the possibility to sputter under different deposition angles or to sputter different materials on the same substrate. The chamber is also equipped with a modular sample stage, which allows for the integration of different sample environments, such as a sample heating and cooling device. The design of HASE is unique in the flexibility. The combination of several different sputtering methods like standard deposition, glancing angle deposition, and high pressure sputter deposition combined with heating and cooling possibil-ities of the sample, the large exit windows, and the degree of automation facilitate many different grazing incidence X-ray scattering experiments, such as grazing incidence small and wide angle X-ray scattering, in one setup. In this paper we describe in detail the design and the performance of the new equipment and present the installation of the HASE apparatus at the Micro and Nano focus X-ray Scattering beamline (MiNaXS) at PETRA III. Furthermore, we describe the measurement options and present some selected results. The HASE setup has been successfully commissioned and is now available for users.

  1. A new highly automated sputter equipment for in situ investigation of deposition processes with synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Doehrmann, Ralph; Botta, Stephan; Buffet, Adeline; Santoro, Gonzalo; Schlage, Kai; Schwartzkopf, Matthias; Risch, Johannes F. H.; Mannweiler, Roman; Roth, Stephan V. [DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg (Germany); Bommel, Sebastian [DESY, Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg (Germany); Institut fuer Physik, Humboldt-Universitaet zu Berlin, Newtonstr. 15, D-12489 Berlin (Germany); Brunner, Simon; Metwalli, Ezzeldin; Mueller-Buschbaum, Peter [Lehrstuhl fuer Funktionelle Materialien, Physik-Department, Technische Universitaet Muenchen, James-Franck-Str. 1, D-85748 Garching (Germany)

    2013-04-15

    HASE (Highly Automated Sputter Equipment) is a new mobile setup developed to investigate deposition processes with synchrotron radiation. HASE is based on an ultra-high vacuum sputter deposition chamber equipped with an in-vacuum sample pick-and-place robot. This enables a fast and reliable sample change without breaking the vacuum conditions and helps to save valuable measurement time, which is required for experiments at synchrotron sources like PETRA III at DESY. An advantageous arrangement of several sputter guns, mounted on a rotative flange, gives the possibility to sputter under different deposition angles or to sputter different materials on the same substrate. The chamber is also equipped with a modular sample stage, which allows for the integration of different sample environments, such as a sample heating and cooling device. The design of HASE is unique in the flexibility. The combination of several different sputtering methods like standard deposition, glancing angle deposition, and high pressure sputter deposition combined with heating and cooling possibil-ities of the sample, the large exit windows, and the degree of automation facilitate many different grazing incidence X-ray scattering experiments, such as grazing incidence small and wide angle X-ray scattering, in one setup. In this paper we describe in detail the design and the performance of the new equipment and present the installation of the HASE apparatus at the Micro and Nano focus X-ray Scattering beamline (MiNaXS) at PETRA III. Furthermore, we describe the measurement options and present some selected results. The HASE setup has been successfully commissioned and is now available for users.

  2. Understanding aerosol based emissions in a post combustion CO2 capture process: parameter testing and mechanisms

    NARCIS (Netherlands)

    Khakharia, P.M.; Brachert, L.; Mertens, J.; Anderlohr, C.; Huizinga, A.; Fernandez, E.S.; Schallert, B.; Schaber, K.; Vlugt, T.J.H.; Goetheer, E.L.V.

    2015-01-01

    Solvent emissions from a Post Combustion CO2 Capture (PCCC) process can lead to environmental hazards and higher operating cost. Aerosol based emissions in the order of grams per Nm3 have been reported from PCCC plants. These emissions are attributed to the presence of particles such as sulphuric ac

  3. Membrane-integrated oxy-fuel combustion of coal: Process design and simulation

    NARCIS (Netherlands)

    Chen, Wei; Ham, van der A.G.J.; Nijmeijer, A.; Winnubst, A.J.A.

    2015-01-01

    A membrane-integrated oxy-fuel combustion process is designed and simulated in UniSim Design®. The results of the simulation indicate that a net efficiency of 31.8% is obtained for a coal-fired power plant of 182 MWth (assuming only carbon in the coal), including the compression of CO2 to 100 bar. T

  4. Combustion and explosion processes in physical chemistry and technology of inorganic materials

    Energy Technology Data Exchange (ETDEWEB)

    Merzhanov, Alexander G [Institute of Structural Macrokinetics and Materials Science, Russian Academy of Sciences, Chernogolovka, Moscow Region (Russian Federation)

    2003-04-30

    This review is the first attempt to generalise, in a descriptive-conceptual form, material-synthesising and material-affecting combustion and explosion processes and relevant physicochemical, technological and materials science problems with special emphasis on their practical (technological and industrial) applications.

  5. Two-stage pervaporation process for effective in situ removal acetone-butanol-ethanol from fermentation broth.

    Science.gov (United States)

    Cai, Di; Hu, Song; Miao, Qi; Chen, Changjing; Chen, Huidong; Zhang, Changwei; Li, Ping; Qin, Peiyong; Tan, Tianwei

    2017-01-01

    Two-stage pervaporation for ABE recovery from fermentation broth was studied to reduce the energy cost. The permeate after the first stage in situ pervaporation system was further used as the feedstock in the second stage of pervaporation unit using the same PDMS/PVDF membrane. A total 782.5g/L of ABE (304.56g/L of acetone, 451.98g/L of butanol and 25.97g/L of ethanol) was achieved in the second stage permeate, while the overall acetone, butanol and ethanol separation factors were: 70.7-89.73, 70.48-84.74 and 9.05-13.58, respectively. Furthermore, the theoretical evaporation energy requirement for ABE separation in the consolidate fermentation, which containing two-stage pervaporation and the following distillation process, was estimated less than ∼13.2MJ/kg-butanol. The required evaporation energy was only 36.7% of the energy content of butanol. The novel two-stage pervaporation process was effective in increasing ABE production and reducing energy consumption of the solvents separation system. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Processing of Bi-2212 and Nb$_3$Sn studied in situ by high energy synchrotron diffraction and micro-tomography

    CERN Document Server

    Kadar, Julian

    Next generation superconducting wires have been studied to obtain more information on the evolution of phase growth, crystallite size and strain state during wire processing. The high energy scattering beam line ID15 at the European Synchrotron Radiation Facility provides a very high flux of high energy photons for very fast in situ X-ray diffraction and micro-tomography studies of Bi-2212/Ag and Nb$_3$S/Cu wire samples. The typical wire processing conditions could be imitated in the X-ray transparent furnace at ID15 for diffraction and tomography studies. Efficient data analysis is mandatory in order to handle the very fast data acquisition rate. For this purpose an Excel-VBA based program was developed that allows a semi-automated fitting and tracking of peaks with pre-set constraints. With this method, more than one thousand diffraction patterns have been analysed to extract d-spacing, peak intensity and peak width values. X ray absorption micro tomograms were recorded simultaneously with the X-ray diffrac...

  7. Single kaolinite nanometer layers prepared by an in situ polymerization-exfoliation process in the presence of ionic liquids.

    Science.gov (United States)

    Letaief, Sadok; Leclercq, Jérôme; Liu, Yun; Detellier, Christian

    2011-12-20

    A simple chemical route for the exfoliation of kaolinite in the presence of polymerizable ionic liquids and the resulting obtainment of exfoliated nanocomposites is reported. The exfoliation was achieved using three different ionic liquids structurally bearing a vinyl group: 1-methyl-3-(4-vinylbenzyl)imidazolium chloride salt (IL_1), 1-methyl-1-(4-vinylbenzyl)pyrrolidinium chloride (IL_2), and 1-methyl-3-vinyl imidazolium iodide (IL_3) and a urea-kaolinite intercalate as precursor. The reaction was done in one step by an in situ polymerization-exfoliation process. (13)C CP/MAS NMR spectra confirmed the spontaneous polymerization of the ionic liquid during the exfoliation process to afford atactic polystyrene derivatives in the case of IL_1 and IL_2. The amount of organic material in the exfoliated nanocomposite was close to 30% as shown by thermal gravimetric analysis. This amount is small in comparison to the amount obtained when the exfoliation was done using sodium polyacrylate (Letaief and Detellier, Langmuir2009, 25, 10975). XRD as well as SEM analysis confirmed a total exfoliation of the kaolinite when the reaction was done using urea kaolinite, whereas a microcomposite, made predominantly of kaolinite platelet aggregates dispersed in the polymeric matrix, was formed when dimethylsulfoxide kaolinite was used as the precursor.

  8. Study of instrumentation needs for process control and safety in coal fluidized-bed combustion systems

    Energy Technology Data Exchange (ETDEWEB)

    Herzenberg, C.L.; Griggs, K.E.; Henry, R.F.; Podolski, W.F.

    1981-02-01

    A study was conducted to evaluate the current state of the art of instrumentation for planned and operating fluidized-bed combustion systems. This study is intended to identify instrumentation needs and serve as a data base for projects to develop this instrumentation. A considerable number of needs for measurements for which presently available instrumentation is not suitable were reported by respondents. The identified deficiencies are presented with the associated physical parameter ranges for FBC processes. New techniques and instrumentation under development, as well as some available alternative instruments, are discussed briefly. Also, newly instituted mechanisms for technical information exchange on instrumentation for fossil energy applications are identified. Development of instruments to meet the identified measurement deficiencies is recommended in order to ensure the feasibility of automatic control of large-scale fluidized-bed combustion systems, and to advance the state of the art of fluidized-bed combustion technology.

  9. Artificial intelligence for the modeling and control of combustion processes: a review

    Energy Technology Data Exchange (ETDEWEB)

    Soteris A. Kalogirou, [Higher Technical Institute, Nicosia (Cyprus). Department of Mechanical Engineering

    2003-07-01

    Artificial intelligence (AI) systems are widely accepted as a technology offering an alternative way to tackle complex and ill-defined problems. They can learn from examples, are fault tolerant in the sense that they are able to handle noisy and incomplete data, are able to deal with non-linear problems, and once trained can perform prediction and generalization at high speed. They have been used in diverse applications in control, robotics, pattern recognition, forecasting, medicine, power systems, manufacturing, optimization, signal processing, and social/psychological sciences. They are particularly useful in system modeling such as in implementing complex mappings and system identification. AI systems comprise areas like, expert systems, artificial neural networks, genetic algorithms, fuzzy logic and various hybrid systems, which combine two or more techniques. The major objective of this paper is to illustrate how AI techniques might play an important role in modeling and prediction of the performance and control of combustion process. The paper outlines an understanding of how AI systems operate by way of presenting a number of problems in the different disciplines of combustion engineering. The various applications of AI are presented in a thematic rather than a chronological or any other order. Problems presented include two main areas: combustion systems and internal combustion (IC) engines. Combustion systems include boilers, furnaces and incinerators modeling and emissions prediction, whereas, IC engines include diesel and spark ignition engines and gas engines modeling and control. Results presented in this paper, are testimony to the potential of AI as a design tool in many areas of combustion engineering. 109 refs., 31 figs., 11 tabs.

  10. Artificial intelligence for the modeling and control of combustion processes: a review

    Energy Technology Data Exchange (ETDEWEB)

    Kalogirou, S.A. [Higher Technical Inst., Nicosia, Cyprus (Greece). Dept. of Mechanical Engineering

    2003-07-01

    Artificial intelligence (AI) systems are widely accepted as a technology offering an alternative way to tackle complex and ill-defined problems. They can learn from examples, are fault tolerant in the sense that they are able to handle noisy and incomplete data, are able to deal with non-linear problems, and once trained can perform prediction and generalization at high speed. They have been used in diverse applications in control, robotics, pattern recognition, forecasting, medicine, power systems, manufacturing, optimization, signal processing, and social/psychological sciences. They are particularly useful in system modeling such as in implementing complex mappings and system identification. Al systems comprise areas like, expert systems, artificial neural networks, genetic algorithms, fuzzy logic and various hybrid systems, which combine two or more techniques. The major objective of this paper is to illustrate how Al techniques might play an important role in modeling and prediction of the performance and control of combustion process. The paper outlines an understanding of how AI systems operate by way of presenting a number of problems in the different disciplines of combustion engineering. The various applications of AI are presented in a thematic rather than a chronological or any other order. Problems presented include two main areas: combustion systems and internal combustion (IC) engines. Combustion systems include boilers, furnaces and incinerators modeling and emissions prediction, whereas, IC engines include diesel and spark ignition engines and gas engines modeling and control. Results presented in this paper, are testimony to the potential of Al as a design tool in many areas of combustion engineering. (author)

  11. New in situ solid-state NMR techniques for probing the evolution of crystallization processes: pre-nucleation, nucleation and growth.

    Science.gov (United States)

    Hughes, Colan E; Williams, P Andrew; Keast, Victoria L; Charalampopoulos, Vasileios G; Edwards-Gau, Gregory R; Harris, Kenneth D M

    2015-01-01

    The application of in situ techniques for investigating crystallization processes promises to yield significant new insights into fundamental aspects of crystallization science. With this motivation, we recently developed a new in situ solid-state NMR technique that exploits the ability of NMR to selectively detect the solid phase in heterogeneous solid-liquid systems (of the type that exist during crystallization from solution), with the liquid phase "invisible" to the measurement. As a consequence, the technique allows the first solid particles produced during crystallization to be observed and identified, and allows the evolution of different solid phases (e.g., polymorphs) present during the crystallization process to be monitored as a function of time. This in situ solid-state NMR strategy has been demonstrated to be a powerful approach for establishing the sequence of solid phases produced during crystallization and for the discovery of new polymorphs. The most recent advance of the in situ NMR methodology has been the development of a strategy (named "CLASSIC NMR") that allows both solid-state NMR and liquid-state NMR spectra to be measured (essentially simultaneously) during the crystallization process, yielding information on the complementary changes that occur in both the solid and liquid phases as a function of time. In this article, we present new results that highlight the application of our in situ NMR techniques to successfully unravel different aspects of crystallization processes, focusing on: (i) the application of a CLASSIC NMR approach to monitor competitive inclusion processes in solid urea inclusion compounds, (ii) exploiting liquid-state NMR to gain insights into co-crystal formation between benzoic acid and pentafluorobenzoic acid, and (iii) applications of in situ solid-state NMR for the discovery of new solid forms of trimethylphosphine oxide and L-phenylalanine. Finally, the article discusses a number of important fundamental issues

  12. In situ7Li and 133Cs nuclear magnetic resonance investigations on the role of Cs+ additive in lithium-metal deposition process

    Science.gov (United States)

    Hu, Jian Zhi; Zhao, Zhenchao; Hu, Mary Y.; Feng, Ju; Deng, Xuchu; Chen, Xilin; Xu, Wu; Liu, Jun; Zhang, Ji-Guang

    2016-02-01

    Cesium ion (Cs+) has been reported to be an effective electrolyte additive to suppress Li dendrite growth which prevents the application of lithium (Li) metal as an anode for rechargeable Li batteries. In this work, we investigated the effect of Cs+ additive on Li depositions using quantitative in situ7Li and 133Cs nuclear magnetic resonance (NMR) with planar symmetric Li cells. It's found that the addition of Cs+ can significantly enhance both the formation of well aligned Li nanorods and reversibility of the Li electrode. In situ133Cs NMR directly confirms that Cs+ migrates to Li electrode to form a positively charged electrostatic shield during the charging process. Much more electrochemical "active" Li was found in Li films deposited with Cs+ additive, while more electrochemical "dead" and thicker Li rods were identified in Li films deposited without Cs+. Combining the in situ and the previous ex-situ results, a Li deposition model has been proposed to explain these observations.

  13. New insight in the template decomposition process of large zeolite ZSM-5 crystals: an in situ UV-Vis/fluorescence micro-spectroscopy study

    NARCIS (Netherlands)

    Karwacki, L.; Weckhuysen, B.M.

    2011-01-01

    A combination of in situ UV-Vis and confocal fluorescence micro-spectroscopy was used to study the template decomposition process in large zeolite ZSM-5 crystals. Correlation of polarized light dependent UV-Vis absorption spectra with confocal fluorescence emission spectra in the 400–750 nm region

  14. A Pd-Catalyzed in situ domino process for mild and quantitative production of 2,5-dimethylfuran directly from carbohydrates

    DEFF Research Database (Denmark)

    Li, Hu; Zhao, Wenfeng; Riisager, Anders

    2017-01-01

    An in situ domino process has been developed to be highly efficient for direct and mild conversion of various hexose sugars to the biofuel 2,5-dimethylfuran in almost quantitative yields, without separation of unstable intermediates at 120 °C in n-butanol, by using polymethylhydrosiloxane and hyd...

  15. New insight in the template decomposition process of large zeolite ZSM-5 crystals: an in situ UV-Vis/fluorescence micro-spectroscopy study

    NARCIS (Netherlands)

    Karwacki, L.; Weckhuysen, B.M.

    2011-01-01

    A combination of in situ UV-Vis and confocal fluorescence micro-spectroscopy was used to study the template decomposition process in large zeolite ZSM-5 crystals. Correlation of polarized light dependent UV-Vis absorption spectra with confocal fluorescence emission spectra in the 400–750 nm region a

  16. Enzymatic in-situ generation of H2O2 for decolorization of Acid Blue 113 by fenton process

    Directory of Open Access Journals (Sweden)

    Karimi Afzal

    2012-01-01

    Full Text Available Decolorization of Acid Blue 113 in an aqueous medium by bio-Fenton process has been investigated in this research. Enzymatic oxidation of glucose was performed to in-situ generation of H2O2 which was employed to react with Fe2+ for producing hydroxyl radicals. The effect of various parameters include concentrations of 113, glucose, and FeSO4, activity of glucose oxidase (GOx and the effect of pH were assessed. The highest decolorization of AB 113 were achieved at Fe2+ concentration of 0.2 mmol/L, pH =4.0, glucose concentration of 0.018 mol/L, and glucose oxidase activity of 2500 U/L in the constant temperature (23 ±0.1ºC and constant shaking rate (160 r/min, while the concentration of 113 was 40 mg/L. In these conditions, 113 decolorization efficiency after 60 min was obtained about 95%.

  17. Centrifugal casting processes of manufacturing in situ functionally gradient composite materials of Al-19Si-5Mg alloy

    Institute of Scientific and Technical Information of China (English)

    XIE Yong; LIU Changming; ZHAI Yanbo; WANG Kai; LING Xuedong

    2009-01-01

    Cylindrical components of in situ functionally gradient composite materials of Al-19Si-5Mg alloy were manufactured by centrifugal casting. Microstructure characteristics of the manufactured components were observed and the effects of the used process factors on these character-istics were analyzed. The results of observations shows that, in thickness, the components possess microstructures accumulating lots of Mg2Si particles and a portion of primary silicon particles in the inner layer, a little Mg2Si and primary silicon particles in the outer layer, and without any Mg2Si and primary silicon particle in the middle layer. The results of the analysis indicate that the rotation rate of centrifugal casting, mould temperature, and melt pouring temperature have evidently affected the accumulation of the second phase particles. Also, the higher the centrifugal rotation rate, mould temperature, and melt pouring temperature are, the more evident in the inner layer the degree of accumulation of Mg2Si and primary silicon particles is.

  18. Comparison of biodiesel production from sewage sludge obtained from the A²/O and MBR processes by in situ transesterification.

    Science.gov (United States)

    Qi, Juanjuan; Zhu, Fenfen; Wei, Xiang; Zhao, Luyao; Xiong, Yiqun; Wu, Xuemin; Yan, Fawei

    2016-03-01

    The potential of two types of sludge obtained from the anaerobic-anoxic-oxic (A(2)/O) and membrane bioreactor (MBR) processes as lipid feedstock for biodiesel production via in situ transesterification was investigated. Experiments were conducted to determine the optimum conditions for biodiesel yield using three-factor and four-level orthogonal and single-factor tests. Several factors, namely, methanol-to-sludge mass ratio, acid concentration, and temperature, were examined. The optimum yield of biodiesel (16.6% with a fatty acid methyl ester purity of 96.7%) from A(2)/O sludge was obtained at a methanol-to-sludge mass ratio of 10:1, a temperature of 60°C, and a H2SO4 concentration of 5% (v/v). Meanwhile, the optimum yield of biodiesel (4.2% with a fatty acid methyl ester purity of 92.7%) from MBR sludge was obtained at a methanol-to-sludge mass ratio of 8:1, a temperature of 50°C, and a H2SO4 concentration of 5% (v/v). In this research, A(2)/O technology with a primary sedimentation tank is more favorable for obtaining energy from wastewater than MBR technology.

  19. In-situ deposition and processing of YBa2Cu3O(7-x) films and multilayers for optoelectronic devices

    Science.gov (United States)

    Villegier, J. C.; Moriceau, H.; Boucher, H.; di Cioccio, L.; Chicault, R.

    1991-03-01

    In situ direct deposition at about 700 C of thin YBa2Cu3O(7-x) superconductive films and multilayers has been done by three techniques using stoichiometric YBa2Cu3O(7-x) sintered targets. Excimer laser ablation in a dc magnetron system with hollow and planar targets leads to 0.5-, 1.2-, and 2.5-in diameter uniformly superconductive layers under static conditions. High critical current densities associated with low resistivity and good epitaxial behavior are achieved on top of MgO, SrTiO3, LaAlO3, and YSZ single-crystal wafers. High-quality c-oriented films are routinely obtained by means of a dc magnetron on large sapphire substrates covered by a YSZ RF sputtered buffer layer. The infrared properties of such films have been checked at 1.15-micron wavelength. In order to achieve active devices, small YBa2Cu3O7-YSZ-Ag tunnel junctions and arrays have been successfully patterned in the superconductor/insulator/normal-metal trilayers using SNOP (selective niobium overlap process).

  20. In situ X-ray diffraction study of crystallization process of GeSbTe thin films during heat treatment

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Naohiko [Toyota Central R and D Labs., Inc., Nagakute, Aichi 480-1192 (Japan)]. E-mail: e0957@mosk.tytlabs.co.jp; Konomi, Ichiro [Toyota Central R and D Labs., Inc., Nagakute, Aichi 480-1192 (Japan); Seno, Yoshiki [Toyota Central R and D Labs., Inc., Nagakute, Aichi 480-1192 (Japan); Motohiro, Tomoyoshi [Toyota Central R and D Labs., Inc., Nagakute, Aichi 480-1192 (Japan)

    2005-05-15

    The crystallization processes of the Ge{sub 2}Sb{sub 2}Te{sub 5} thin film used for PD and DVD-RAM were studied in its realistic optical disk film configurations for the first time by X-ray diffraction using an intense X-ray beam of a synchrotron orbital radiation facility (SPring-8) and in situ quick detection with a Position-Sensitive-Proportional-Counter. The dependence of the amorphous-to-fcc phase-change temperature T{sub 1} on the rate of temperature elevation R{sub et} gave an activation energy E{sub a}: 0.93 eV much less than previously reported 2.2 eV obtained from a model sample 25-45 times thicker than in the real optical disks. The similar measurement on the Ge{sub 4}Sb{sub 1}Te{sub 5} film whose large reflectance change attains the readability by CD-ROM drives gave E{sub a}: 1.13 eV with larger T{sub 1} than Ge{sub 2}Sb{sub 2}Te{sub 5} thin films at any R{sub et} implying a lower sensitivity in erasing as well as a better data stability of the phase-change disk.

  1. In Situ Synthesis of Al-Si-Cu Alloy During Brazing Process and Mechanical Property of Brazing Joint

    Directory of Open Access Journals (Sweden)

    LONG Wei-min

    2016-06-01

    Full Text Available The Al-Si-Cu alloy system is considered to be a promising choice of filler metal for aluminium alloys brazing due to its high strength and low melting point. The greatest obstacle is its lack of plastic forming ability and being difficult to be processed by conventional methods. This disadvantage is ascribed to the considerable amount of brittle CuAl2 intermetallic compound which forms when alloy composition is around the ternary eutectic point. In order to overcome this deficiency, authors of this article proposed to synthesize Al-Si-Cu filler metal by using in situ synthesis method, and the structure and properties of brazing joints were studied. The results show that AlSi alloy is used as the wrap layer, and CuAl alloy is used as the powder core in the composite brazing wire, the two alloys have similar melting points. The machinability of the composite brazing wire is much superior to the traditional Al-Si-Cu filler metal. During the induction brazing of 3A21 alloy, when using AlSi-CuAl composite filler wire, AlSi and CuAl alloys melt almost simultaneously, then after short time holding, Al-Si-Cu braze filler is obtained, the brazing seam has uniform composition and good bonding interface, also, the shearing strength of the brazing joints is higher than the joint brazed by conventional Al-Si-Cu filler metal.

  2. Modeling and optimization of processes for clean and efficient pulverized coal combustion in utility boilers

    Directory of Open Access Journals (Sweden)

    Belošević Srđan V.

    2016-01-01

    Full Text Available Pulverized coal-fired power plants should provide higher efficiency of energy conversion, flexibility in terms of boiler loads and fuel characteristics and emission reduction of pollutants like nitrogen oxides. Modification of combustion process is a cost-effective technology for NOx control. For optimization of complex processes, such as turbulent reactive flow in coal-fired furnaces, mathematical modeling is regularly used. The NOx emission reduction by combustion modifications in the 350 MWe Kostolac B boiler furnace, tangentially fired by pulverized Serbian lignite, is investigated in the paper. Numerical experiments were done by an in-house developed three-dimensional differential comprehensive combustion code, with fuel- and thermal-NO formation/destruction reactions model. The code was developed to be easily used by engineering staff for process analysis in boiler units. A broad range of operating conditions was examined, such as fuel and preheated air distribution over the burners and tiers, operation mode of the burners, grinding fineness and quality of coal, boiler loads, cold air ingress, recirculation of flue gases, water-walls ash deposition and combined effect of different parameters. The predictions show that the NOx emission reduction of up to 30% can be achieved by a proper combustion organization in the case-study furnace, with the flame position control. Impact of combustion modifications on the boiler operation was evaluated by the boiler thermal calculations suggesting that the facility was to be controlled within narrow limits of operation parameters. Such a complex approach to pollutants control enables evaluating alternative solutions to achieve efficient and low emission operation of utility boiler units. [Projekat Ministarstva nauke Republike Srbije, br. TR-33018: Increase in energy and ecology efficiency of processes in pulverized coal-fired furnace and optimization of utility steam boiler air preheater by using in

  3. FORMALIZATION OF DIESEL ENGINE OPERATION CONSIDERING THE EVALUATION OF VELOCITY DURING THE COMBUSTION PROCESSES

    Directory of Open Access Journals (Sweden)

    V. P. Litvinenko

    2015-10-01

    Full Text Available Purpose. Under modern conditions the applying methods and design models as well as the evaluation of the operational characteristics of diesel engines do not completely take into consideration the specifics of the combustion processes. In part, such situation is characterized by the complexity of considering of varied by its nature processes that haven’t been completely investigated. In this context it is necessary to find the new methods and models which would provide relatively simple solutions through the use of integrated factors based on the analysis of parameters of diesel engines. Methodology. The proposed algorithms for the estimating of the combustion process in the form of volumetric and linear velocities is based on the well-known parameters of power and mean effective pressure and allows to compare the efficiency of their behavior in various versions of diesel engines. Findings. The author specified that the volumetric / linear velocity ratio is characterized by some strength and depends on the geometric dimensions of the cylinder-piston group. Due to the assumptions it has become possible to consider the operation of a diesel engine as a system comprising: 1 the subsystem that provides the possibility of obtaining the thermal energy; 2 the subsystem providing the thermal energy transformation; 3 the subsystem that provides the necessary diesel engine power depending on terms of combustion of air-fuel mixture. Originality. The author of the paper proposed the indices of volumetric and linear combustion velocity of air-fuel mixture in the engine cylinder, that allow to obtain the comparative value in different modifications taking into account the possible choice of optimum ratio. Practical value. The usage of indices of volumetric and linear velocities of the combustion processes in the engine cylinder combined with a mathematical model will simplify the method of diesels calculating. Parametric indices of the mentioned velocities

  4. Time Resolved FTIR Analysis of Combustion of Ethanol and Gasoline Combustion in AN Internal Combustion Engine

    Science.gov (United States)

    White, Allen R.; Sakai, Stephen; Devasher, Rebecca B.

    2011-06-01

    In order to pursue In Situ measurements in an internal combustion engine, a MegaTech Mark III transparent spark ignition engine was modified with a sapphire combustion chamber. This modification will allow the transmission of infrared radiation for time-resolved spectroscopic measurements by an infrared spectrometer. By using a Step-scan equipped Fourier transform spectrometer, temporally resolved infrared spectral data were acquired and compared for combustion in the modified Mark III engine. Measurements performed with the FTIR system provide insight into the energy transfer vectors that precede combustion and also provides an in situ measurement of the progress of combustion. Measurements were performed using ethanol and gasoline.

  5. Optimization of post combustion carbon capture process-solvent selection

    Directory of Open Access Journals (Sweden)

    Udara S. P. R. Arachchige, Muhammad Mohsin, Morten C. Melaaen

    2012-01-01

    Full Text Available The reduction of the main energy requirements in the CO2 capture process that is re-boiler duty in stripper section is important. Present study was focused on selection of better solvent concentration and CO2 lean loading for CO2 capture process. Both coal and gas fired power plant flue gases were considered to develop the capture plant with different efficiencies. Solvent concentration was varied from 25 to 40 (w/w % and CO2 lean loading was varied from 0.15 to 0.30 (mol CO2/mol MEA for 70-95 (mol % CO2 removal efficiencies. The optimum specifications for coal and gas processes such as MEA concentration, CO2 lean loading, and solvent inlet flow rate were obtained.

  6. Investigation of solution combustion-processed nickel oxide p-channel thin film transistors

    Science.gov (United States)

    Li, Ya; Liu, Chuan; Wang, Gang; Pei, Yanli

    2017-08-01

    In this work, p-channel thin film transistors (TFTs) with a nickel oxide (NiO) active layer have been synthesized by a solution combustion process. The effect of synthesis parameters was investigated. It was revealed that the metal-acetylacetone complexes and metal-ammine complexes coexist in the solution precursor. The combustion of metal-acetylacetone complexes is dominant in the redox reaction, while the combustion of metal-ammine complexes completes the reaction of residual organic matter. The proportion of both complexes in the solution precursor is key for NiO synthesis, which is tunable by the precursor aging time. The annealing temperature is another key parameter. X-ray photoelectron spectroscopy analysis indicates that organic residues exist in the film annealed at low temperature. In contrast, with the increase in annealing temperature, the Ni3+-related components decreased while the intensity of Ni2+ in the film increased. This results in a decrease in the hole concentration and the degradation of device performance. The p-channel NiO TFTs with a field-effect mobility of 0.015 cm2 V-1 s-1 have been achieved via systemically optimizing precursor aging time and post-annealing temperature. This study successfully demonstrates the potential of combustion solution-processed NiO TFTs with p-channel characteristics.

  7. Combustion Characteristics of Chlorine-Free Solid Fuel Produced from Municipal Solid Waste by Hydrothermal Processing

    Directory of Open Access Journals (Sweden)

    Kunio Yoshikawa

    2012-11-01

    Full Text Available An experimental study on converting municipal solid waste (MSW into chlorine-free solid fuel using a combination of hydrothermal processing and water-washing has been performed. After the product was extracted from the reactor, water-washing experiments were then conducted to obtain chlorine-free products with less than 3000 ppm total chlorine content. A series of combustion experiments were then performed for the products before and after the washing process to determine the chlorine content in the exhaust gas and those left in the ash after the combustion process at a certain temperature. A series of thermogravimetric analyses were also conducted to compare the combustion characteristics of the products before and after the washing process. Due to the loss of ash and some volatile matter after washing process, there were increases in the fixed carbon content and the heating value of the product. Considering the possible chlorine emission, the washing process after the hydrothermal treatment should be necessary only if the furnace temperature is more than 800 °C.

  8. Combustion and Magnetohydrodynamic Processes in Advanced Pulse Detonation Rocket Engines

    Science.gov (United States)

    2012-10-01

    an endothermic process, the parameter θa in this formulation is an averaged activation energy of the key radical-producing reactions. This is a...conserved variables, W = LQ, and by definition LR = RL = I. Now that the governing equations have been linearized with the pro- cess shown in Equation...Radulescu et al. attributed the stabilizing effect of the diluent to the lower temperature in the reaction zone which leads to slower exothermic reaction

  9. Hybrid intelligent control of combustion process for ore-roasting furnace

    Institute of Scientific and Technical Information of China (English)

    Aijun YAN; Tianyou CHAI; Fenghua WU; Pu WANG

    2008-01-01

    Because of its synthetic and complex characteristics, the combustion process of the shaft ore-roasting furnace is very difficult to control stably. A hybrid intelligent control approach is developed which consists of two systems: one is a cascade fuzzy control system with a temperature soft-sensor, and the other is a ratio control system for air flow with a compensation model for heating gas flow and air-fuel ratio. This approach combined intelligent control, soft-sensing and fault diagnosis with conventional control. It can adjust both the heating gas flow and the air-fuel ratio in real time. By this way, the difficulty of online measurement of the furnace temperature is solved, the fault ratios during combustion process is decreased, the steady control of the furnace temperature is achieved, and the gas consumption is reduced. The successful application in shaft furnaces of a mineral processing plant in China indicates its effectiveness.

  10. Carbon stripping - a critical process step in chemical looping combustion of solid fuels

    Energy Technology Data Exchange (ETDEWEB)

    Kramp, M.; Thon, A.; Hartge, E.U.; Heinrich, S.; Werther, J. [Hamburg University of Technology, Institute of Solids Process Engineering and Particle Technology, Hamburg (Germany)

    2012-03-15

    In chemical looping combustion of solid fuels the well-mixed solids flow from the fuel reactor consisting of char, ash, and oxygen carrier particles cannot be completely separated into its constituents before it enters the air reactor. The slip of carbon will thus lead to char oxidation in the wrong reactor. Process simulation was applied to investigate the carbon stripping process in chemical looping combustion of solid fuels. Depending on the fuel choice, without carbon stripping CO{sub 2} capture rates below 50 % are calculated for 4 min of solids residence time in the fuel reactor. In a process with carbon stripper, however, CO{sub 2} capture rates exceeding 90 % can be achieved for both fuels investigated in this work. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Studies of the Combustion Process with Simultaneous Formaldehyde and OH PLIF in a Direct-Injected HCCI Engine

    Science.gov (United States)

    Richter, Mattias; Collin, Robert; Nygren, Jenny; Aldén, Marcus; Hildingsson, Leif; Johansson, Bengt

    This paper presents simultaneous laser based measurements of formaldehyde and OH-radical distributions in a 0.5 liter optical HCCI engine with direct injection. Formaldehyde is formed as an intermediate species when combusting hydrocarbons. The formation occurs through low temperature reactions in an early phase of the combustion process. Later in the process formaldehyde is being consumed. Formaldehyde is, therefore, used as indicator of the first stage of combustion and a marker of zones with low-temperature reactions. The OH radical is formed as an intermediate during the high temperature reactions, and is used as a marker of zones where the combustion is ongoing. The purpose of the investigation was to study how the combustion process is affected by the change in homogeneity that arises from early and late injection, respectively. The measurement technique used was planar laser-induced fluorescence where formaldehyde was excited at 355nm and OH at 283nm.

  12. Test facilities for investigation of combustion processes built at the Technical University of Lodz

    Science.gov (United States)

    Kowalewski, Grzegorz

    2001-04-01

    A number of fundamental research projects devoted to combustion processes have been carried out during the last years in the Department of Heat Technology and Refrigeration of the Technical University of Lodz, Poland. The investigations under various conditions of combustion have been conducted with the following research facilities and equipment: (1) a drop tower with 1.2 sec of microgravity conditions and ca. 1 m3 volume of the experimental package, (2) a test rig with a rotating cylindrical vessel (combustion chamber) up to 6000 rpm, (3) schlieren devices of 300 and 150 mm diameter, including a compact system for experiments in the drop tower, (4) several specialized chambers for combustion of gas- and two-phase mixtures, (5) high speed photography equipment including a 500 fps camera. Some of the experiments and facilities are presented on 27.5 min long video and mentioned in this paper in a form of the editing list of the video. Some examples of abstracts of particular specialized publications are quoted.

  13. Analysis of selected problems of biomass combustion process in batch boilers - experimental and numerical approach

    Directory of Open Access Journals (Sweden)

    Szubel Mateusz

    2016-01-01

    Full Text Available It is possible to list numerous groups of heating units that are used in households, such as boilers, stoves and units used as supporting heat sources, namely fireplaces. In each case, however, the same operational problems may be evoked [1]. To understand the causes of energy losses in a boiler system, a proper definition of significant elements of the unit’s heat balance is necessary. In the group of energy losses, the flue gas loss and the incomplete combustion loss are the most significant factors. The problem with the loss resulting from incomplete combustion, which is related to the presence of combustible substances in the exhaust, is especially significant in case of biomass boilers [2, 3]. The paper presents results of the research and the optimisation of the biomass combustion process in the 180 kW batch boiler. The studies described have been focused on the reduction of the pollutants emission, which was primarily realised by the modifications of the air feeding system. Results of the experiments and the CFD simulations have been compared and discussed. Both in case of the model as well as the experiment, positive influence of the modifications on the emission have been observed.

  14. Effects of processing temperature on in-situ reinforcement formation in Al(Zn/Al2O3(ZnO nanocomposite

    Directory of Open Access Journals (Sweden)

    Ali Maleki

    2015-12-01

    Full Text Available The aim of present work was to investigate effects of processing temperature on the microstructure of in-situ processed aluminum/alumina composites. A new activated powder injection (API method was used to synthesize the aluminum matrix composites by displacement reaction between aluminum and zinc oxide. A mechanically activated mixture of aluminum and zinc oxide powder was injected into a vortex of molten aluminum. Three melting temperatures of 680, 730 and 790 °C were selected as the processing temperatures. The composite slurries were solidified under a pressure of 200 MPa. Microstructures of the samples were studied using electron microscopy and image analysis techniques. Refinement of in-situ reinforcements with increasing processing temperature was observed and rationalized.

  15. An innovative bioelectrochemical-anaerobic digestion-coupled system for in-situ ammonia recovery and biogas enhancement: process performance and microbial ecology

    OpenAIRE

    Zhang, Yifeng; Angelidaki, Irini

    2014-01-01

    Ammonia (NH4+/NH3) inhibition during anaerobic digestion process is one of the most frequent problems existing in biogas plants, resulting in unstable process and reduced biogas production. In this study, we developed a novel hybrid system, consisted of a submersed microbial resource recovery cell (SMRC) and a continuous stirred tank reactor (CSTR), to prevent ammonia toxicity during anaerobic digestion by in-situ ammonia recovery and electricity production. In batch experiment, the ammonia c...

  16. In situ characterization and analysis of Salmonella biofilm formation under meat processing environments using a combined microscopic and spectroscopic approach.

    Science.gov (United States)

    Wang, Huhu; Ding, Shijie; Wang, Guangyu; Xu, Xinglian; Zhou, Guanghong

    2013-11-01

    Salmonella biofilm on food-contact surfaces present on food processing facilities may serve as a source of cross-contamination. In our work, biofilm formation by multi-strains of meat-borne Salmonella incubated at 20 °C, as well as the composition and distribution of extracellular polymeric substances (EPS), were investigated in situ by combining confocal laser scanning microscopy (CLSM), scanning electron microscope (SEM), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and Raman spectroscopy. A standard laboratory culture medium (tryptic soy broth, TSB) was used and compared with an actual meat substrate (meat thawing-loss broth, MTLB). The results indicated that Salmonella grown in both media were able to form biofilms on stainless steel surfaces via building a three-dimensional structure with multilayers of cells. Although the number of biofilm cells grown in MTLB was less than that in TSB, the cell numbers in MTLB was adequate to form a steady and mature biofilm. Salmonella grown in MTLB showed "cloud-shaped" morphology in the mature biofilm, whereas when grown in TSB appeared "reticular-shaped". The ATR-FTIR and Raman analysis revealed a completely different chemical composition between biofilms and the corresponding planktonic cells, and some important differences in biofilms grown in MTLB and in TSB. Importantly, our findings suggested that the progress towards a mature Salmonella biofilm on stainless steel surfaces may be associated with the production of the EPS matrix, mainly consisting of polysaccharides and proteins, which may serve as useful markers of biofilm formation. Our work indicated that a combination of these non-destructive techniques provided new insights into the formation of Salmonella biofilm matrix. © 2013.

  17. Exergetic analysis of cogeneration plants through integration of internal combustion engine and process simulators

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Leonardo de Oliveira [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)], E-mail: leonardo.carvalho@petrobras.com.br; Leiroz, Albino Kalab; Cruz, Manuel Ernani [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil). Programa de Engenharia Mecanica], Emails: leiroz@mecanica.ufrj.br, manuel@mecanica.ufrj.br

    2010-07-01

    Internal combustion engines (ICEs) have been used in industry and power generation much before they were massively employed for transportation. Their high reliability, excellent power-to-weight ratio, and thermal efficiency have made them a competitive choice as main energy converters in small to medium sized power plants. Process simulators can model ICE powered energy plants with limited depth, due to the highly simplified ICE models used. Usually a better understanding of the global effects of different engine parameters is desirable, since the combustion process within the ICE is typically the main cause of exergy destruction in systems which utilize them. Dedicated commercial ICE simulators have reached such a degree of maturity, that they can adequately model a wide spectrum of phenomena that occur in ICEs. However, ICE simulators are unable to incorporate the remaining of power plant equipment and processes in their models. This paper presents and exploits the integration of an internal combustion engine simulator with a process simulator, so as to evaluate the construction of a fully coupled simulation platform to analyze the performance of ICE-based power plants. A simulation model of an actual cogeneration plant is used as a vehicle for application of the proposed computational methodology. The results show that by manipulating the engine mapping parameters, the overall efficiency of the plant can be improved. (author)

  18. The characteristics of the combustion process occurring under real operating conditions of traction

    Science.gov (United States)

    Longwic, R.; Sander, P.

    2016-09-01

    The authors deal with the issues of the Diesel engine under dynamic conditions. The conditions of the dynamic operation of the engine have most frequently been mapped by the method of free acceleration of the engine caused by the change of the position of the fuel dose lever. The article presents the results of indication of the traction Diesel engine under real operating conditions. This allows for the use of a mobile system to indicate the AVL engine built in the vehicle in research. We analysed a number of thermodynamic parameters of the combustion process in various dynamic states, typical for the process of actual operation of the engine, such as working in start-up conditions and immediately after, working in conditions of acceleration and coasting. Formulated conclusions significantly expand the area of knowledge concerning the functioning of the internal combustion engine in dynamic conditions.

  19. Sulfur retention by ash during coal combustion. Part II. A model of the process

    Energy Technology Data Exchange (ETDEWEB)

    Vasilije Manovic; Borislav Grubor; Mladen Ilic; Branimir Jovancicevic

    2003-07-01

    An overall model for sulfur self-retention in ash during coal particle combustion is developed in this paper. It is assumed that sulfur retention during char combustion occurs due to the reaction between SO{sub 2} and CaO in the form of uniformly distributed non-porous grains. Parametric analysis shows that the process of sulfur self-retention is limited by solid diffusion through the non-porous product layer formed on the CaO grains and that the most important coal characteristics which influence sulfur self-retention are coal rank, content of sulfur forms, molar Ca/S ratio and particle radius. A comparison with the experimentally obtained values in a FB reactor showed that the model can adequately predict the kinetics of the process, the levels of the obtained values of the SSR efficiencies, as well as the influence of temperature and coal particle size.

  20. Sulfur retention by ash during coal combustion. Part II. A model of the process

    Directory of Open Access Journals (Sweden)

    BRANIMIR JOVANCICEVIC

    2003-03-01

    Full Text Available An overall model for sulfur self-retention in ash during coal particle combustion is developed in this paper. It is assumed that sulfur retention during char combustion occurs due to the reaction between SO2 and CaO in the form of uniformly distributed non-porous grains. Parametric analysis shows that the process of sulfur self-retention is limited by solid difussion through the non-porous product layer formed on the CaO grains and that the most important coal characteristics which influence sulfur self-retention are coal rank, content of sulfur forms, molar Ca/S ratio and particle radius. A comparison with the experimentally obtained values in a FB reactor showed that the model can adequately predict the kinetics of the process, the levels of the obtained values of the SSR efficiencies, as well as the influence of temperature and coal particle size.

  1. The Siemens pyrolysis-combustion process; Das Siemens Schwel-Brenn-Verfahren

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, D. [Siemens - KWU, Offenbach (Germany)

    1996-12-31

    The market introduction fo the SIEMENS pyrolysis-combustion process is a technical and ecological milestone in thermal waste processing. It bridges the gap between conventional incineration and recycling and is ideally suited for the modern waste management philosophy. The innovative combination of pyrolysis followed by high-temperature combustion produces energy and reusable materials nearly without emissions. (orig/sr) [Deutsch] Die Markteinfuehrung des Schwel-Brenn-Verfahrens hat im Bereich der thermischen Muellentsorgung eine technologische und oekologische Zeitenwende eingeleitet. Es fuegt sich als Bruecke zwischen herkoemmlicher Muellverbrennung und stofflichem Muell-Recyling ideal in das Konzept einer oekologischen Kreislaufwirtschaft. Die innovative Kombination von Muellverschwelung (Pyrolyse) und anschliessender Hochtemperaturverbrennung wandelt den unvermeidbaren Restmuell nahezu rueckstandsfrei in Wertstoffe und Energie um. (orig/SR)

  2. Reaction Mechanisms and HCCI Combustion Processes of Mixtures of n-Heptane and the Butanols

    Directory of Open Access Journals (Sweden)

    Hu eWang

    2015-03-01

    Full Text Available A reduced primary reference fuel (PRF-Alcohol-Di-tert-butyl Peroxide (DTBP mechanism with 108 species and 435 reactions, including sub-mechanisms of PRF, methanol, ethanol, DTBP and the four butanol isomers, is proposed for homogeneous charge compression ignition (HCCI engine combustion simulations of butanol isomers/n-heptane mixtures. HCCI experiments fuelled with butanol isomer/n-heptane mixtures on two different engines are conducted for the validation of proposed mechanism. The mechanism has been validated against shock tube ignition delays, laminar flame speeds, species profiles in premixed flames and engine HCCI combustion data, and good agreements with experimental results are demonstrated under various validation conditions. It is found that although the reactivity of neat tert-butanol is the lowest, mixtures of tert-butanol/n-heptane exhibit the highest reactivity among the butanol isomer/n-heptane mixtures if the n-heptane blending ratio exceeds 20% (mole. Kinetic analysis shows that the highest C-H bond energy in the tert-butanol molecule is partially responsible for this phenomenon. It is also found that the reaction tC4H9OH+CH3O2 =tC4H9O+CH3O2H plays important role and eventually produces the OH radical to promote the ignition and combustion. The proposed mechanism is able to capture HCCI combustion processes of the butanol/n-heptane mixtures under different operating conditions. In addition, the trend that tert-butanol /n-heptane has the highest reactivity is also captured in HCCI combustion simulations. The results indicate that the current mechanism can be used for HCCI engine predictions of PRF and alcohol fuels.

  3. Multi-phase Combustion and Transport Processes Under the Influence of Acoustic Excitation

    OpenAIRE

    Wegener, Jeffrey Lewis

    2014-01-01

    This experimental study examined the coupling of acoustics with reactive multiphase transport processes and shear flows. The first portion of this dissertation deals with combustion of various liquid fuels when under the influence of externally applied acoustic excitation. For this study, an apparatus at the Energy and Propulsion ResearchLaboratory, UCLA, used a horizontal waveguide to create a standing acoustic wave, wherein burning fuel droplets were positioned near pressure nodes within th...

  4. Charge Splitting In Situ Recorder (CSIR) for Real-Time Examination of Plasma Charging Effect in FinFET BEOL Processes.

    Science.gov (United States)

    Tsai, Yi-Pei; Hsieh, Ting-Huan; Lin, Chrong Jung; King, Ya-Chin

    2017-09-18

    A novel device for monitoring plasma-induced damage in the back-end-of-line (BEOL) process with charge splitting capability is first-time proposed and demonstrated. This novel charge splitting in situ recorder (CSIR) can independently trace the amount and polarity of plasma charging effects during the manufacturing process of advanced fin field-effect transistor (FinFET) circuits. Not only does it reveal the real-time and in situ plasma charging levels on the antennas, but it also separates positive and negative charging effect and provides two independent readings. As CMOS technologies push for finer metal lines in the future, the new charge separation scheme provides a powerful tool for BEOL process optimization and further device reliability improvements.

  5. An experimental set-up to apply polarization modulation to infrared reflection absorption spectroscopy for improved in situ studies of atmospheric corrosion processes.

    Science.gov (United States)

    Wiesinger, R; Schade, U; Kleber, Ch; Schreiner, M

    2014-06-01

    A new set-up for improved monitoring of atmospheric corrosion processes in situ and in real-time is presented. To characterize chemical structures of thin films on metal surfaces surface sensitive analytical techniques are required. One possible technique is Infrared Reflection Absorption Spectroscopy (IRRAS) which has become an established method to investigate surface corrosion films of thicknesses less than 200 nm. However, there are limitations related to the sensitivity of these measurements, in case of investigating ultrathin films or absorption bands of interest, surface species are superimposed by atmospheric background absorption, which changes during in situ measurements in ambient atmospheres. These difficulties of in situ surface reflection measurements can be eliminated by availing the polarization selectivity of adsorbed surface species. At grazing angles of incidence the absorption of p-polarized infrared radiation by thin surface films on metals is enhanced, while the absorption of s-polarized light by this film is nearly zero. This different behavior of the polarization properties leads to strong selection rules at the surface and can therefore be used to identify molecules adsorbed on metal surfaces. Polarization Modulation (PM) of the infrared (IR) light takes advantage of this disparity of polarization on sample surfaces and in combination with IRRAS yielding a very sensitive and surface-selective method for obtaining IR spectra of ultra-thin films on metal surfaces. An already existing in situ IRRAS/Quartz Crystal Microbalance weathering cell was combined with PM and evaluated according to its applicability to study in situ atmospheric corrosion processes. First real-time measurements on silver samples exposed to different atmospheres were performed showing the advantage of PM-IRRAS compared to conventional IRRAS for such investigations.

  6. Use of the graphical analytic methods of studying the combustion processes in the internal combustion engine combustion chamber on the basis of similarity criterion

    Directory of Open Access Journals (Sweden)

    S. V. Krasheninnikov

    2014-10-01

    Full Text Available The task of improving the economic and ecological parameters of the internal combustion engines remains topical within the frameworks of the modern engine-building technology. Since a combustion engine is a complex system combining such units as an intake manifold, combustion chamber, exhaust manifold, one of directions of the engine development is adjustment of the joint operation of its units. The specified adjustment should better be performed with the use of the so-called integral characteristics. The author means under an integral characteristic the rating plate of a unit (engine containing information about all the possible modes and conditions of its use, specifies the optimal operating range and indicates all the basic values of efficiency – reliability – environmental friendliness at each point of its field. As a rule, integral characteristics are multi-parametric. It is common practice to coordinate the field of such characteristic by similarity criteria determining the unit or engine behavior in whole.

  7. The Process of TiB2-Cu Composite Phase and Structure Formation during Combustion Synthesis

    Institute of Scientific and Technical Information of China (English)

    XU Qiang; ZHANG Xinghong; HAN Jiecai; PAN Wei

    2006-01-01

    The reaction process of combustion synthesis for TiB2- Cu was investigated in detail using combustion-wave arresting experiment, X-ray diffraction (XRD) analysis, SEM analysis and differential thermal analysis ( DTA ). The XRD analysis results for the different parts of the quenched specimen shaw that TiCux intermetallic phase firstly forms with the propagation of combustion wave, and then Ti1.87 B50 and Ti3 B4 metastable phases come forth due to the diffusion of B atoms and finally the stable TiB2 phase forms because of the continuous diffusion of B atoms. The formation of TiB2 phase is not completed by one step, but undergoes several transient processes. The process of reaction synthesis for Ti-B-Cu ternary system can be divided into three main stages: melting of Cu and Ti, and the formation of Cu- Ti melt and few TiCux , TiBx intermetallic phases; large numbers of TiCux intermetallic phases formation and some fine TiB2 particles precipitation; and the TiB2 particles coarsening and the stable TiB2 and Cu two phases formation in the final product.

  8. Combustion iron distribution and deposition

    Science.gov (United States)

    Luo, Chao; Mahowald, N.; Bond, T.; Chuang, P. Y.; Artaxo, P.; Siefert, R.; Chen, Y.; Schauer, J.

    2008-03-01

    Iron is hypothesized to be an important micronutrient for ocean biota, thus modulating carbon dioxide uptake by the ocean biological pump. Studies have assumed that atmospheric deposition of iron to the open ocean is predominantly from mineral aerosols. For the first time we model the source, transport, and deposition of iron from combustion sources. Iron is produced in small quantities during fossil fuel burning, incinerator use, and biomass burning. The sources of combustion iron are concentrated in the industrialized regions and biomass burning regions, largely in the tropics. Model results suggest that combustion iron can represent up to 50% of the total iron deposited, but over open ocean regions it is usually less than 5% of the total iron, with the highest values (ocean biogeochemistry the bioavailability of the iron is important, and this is often estimated by the fraction which is soluble (Fe(II)). Previous studies have argued that atmospheric processing of the relatively insoluble Fe(III) occurs to make it more soluble (Fe(II)). Modeled estimates of soluble iron amounts based solely on atmospheric processing as simulated here cannot match the variability in daily averaged in situ concentration measurements in Korea, which is located close to both combustion and dust sources. The best match to the observations is that there are substantial direct emissions of soluble iron from combustion processes. If we assume observed soluble Fe/black carbon ratios in Korea are representative of the whole globe, we obtain the result that deposition of soluble iron from combustion contributes 20-100% of the soluble iron deposition over many ocean regions. This implies that more work should be done refining the emissions and deposition of combustion sources of soluble iron globally.

  9. Calibrating IR Cameras for In-Situ Temperature Measurement During the Electron Beam Melting Process using Inconel 718 and Ti-Al6-V4

    Energy Technology Data Exchange (ETDEWEB)

    Dinwiddie, Ralph Barton [ORNL; Lloyd, Peter D [ORNL; Dehoff, Ryan R [ORNL; Lowe, Larry E [ORNL

    2016-01-01

    The Department of Energy s (DOE) Manufacturing Demonstration Facility (MDF) at Oak Ridge National Laboratory (ORNL) provides world-leading capabilities in advanced manufacturing (AM) facilities which leverage previous, on-going government investments in materials science research and characterization. MDF contains systems for fabricating components with complex geometries using AM techniques (i.e. 3D-Printing). Various metal alloy printers, for example, use electron beam melting (EBM) systems for creating these components which are otherwise extremely difficult- if not impossible- to machine. ORNL has partnered with manufacturers on improving the final part quality of components and developing new materials for further advancing these devices. One method being used to study (AM) processes in more depth relies on the advanced imaging capabilities at ORNL. High performance mid-wave infrared (IR) cameras are used for in-situ process monitoring and temperature measurements. However, standard factory calibrations are insufficient due to very low transmissions of the leaded glass window required for X-ray absorption. Two techniques for temperature calibrations will be presented and compared. In-situ measurement of emittance will also be discussed. Ample information can be learned from in-situ IR process monitoring of the EBM process. Ultimately, these imaging systems have the potential for routine use for online quality assurance and feedback control.

  10. Fault and anthropogenic processes in central California constrained by satellite and airborne InSAR and in-situ observations

    Science.gov (United States)

    Liu, Zhen; Lundgren, Paul

    2016-07-01

    , but are subject to severe decorrelation. The L-band ALOS and UAVSAR SAR sensors provide improved coherence compared to the shorter wavelength radar data. Joint analysis of UAVSAR and ALOS interferometry measurements show clear variability in deformation along the fault strike, suggesting variable fault creep and locking at depth and along strike. Modeling selected fault transects reveals a distinct change in surface creep and shallow slip deficit from the central creeping section towards the Parkfield transition. In addition to fault creep, the L-band ALOS, and especially ALOS-2 ScanSAR interferometry, show large-scale ground subsidence in the SJV due to over-exploitation of groundwater. Groundwater related deformation is spatially and temporally variable and is composed of both recoverable elastic and non-recoverable inelastic components. InSAR time series are compared to GPS and well-water hydraulic head in-situ time series to understand water storage processes and mass loading changes. We are currently developing poroelastic finite element method models to assess the influence of anthropogenic processes on surface deformation and fault mechanics. Ongoing work is to better constrain both tectonic and non-tectonic processes and understand their interaction and implication for regional earthquake hazard.

  11. Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbon Fuels: Thermochemical Research Pathways with In Situ and Ex Situ Upgrading of Fast Pyrolysis Vapors

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, Abhijit [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sahir, A. H. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tan, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Humbird, David [DWH Process Consulting, Denver, CO (United States); Snowden-Swan, Lesley J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Meyer, Pimphan A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ross, Jeff [Harris Group, Inc., Seattle, WA (United States); Sexton, Danielle [Harris Group, Inc., Seattle, WA (United States); Yap, Raymond [Harris Group, Inc., Seattle, WA (United States); Lukas, John [Harris Group, Inc., Seattle, WA (United States)

    2015-03-01

    This report was developed as part of the U.S. Department of Energy’s Bioenergy Technologies Office’s efforts to enable the development of technologies for the production of infrastructure-compatible, cost-competitive liquid hydrocarbon fuels from biomass. Specifically, this report details two conceptual designs based on projected product yields and quality improvements via catalyst development and process integration. It is expected that these research improvements will be made within the 2022 timeframe. The two conversion pathways detailed are (1) in situ and (2) ex situ upgrading of vapors produced from the fast pyrolysis of biomass. While the base case conceptual designs and underlying assumptions outline performance metrics for feasibility, it should be noted that these are only two of many other possibilities in this area of research. Other promising process design options emerging from the research will be considered for future techno-economic analysis. Both the in situ and ex situ conceptual designs, using the underlying assumptions, project MFSPs of approximately $3.5/gallon gasoline equivalent (GGE). The performance assumptions for the ex situ process were more aggressive with higher distillate (diesel-range) products. This was based on an assumption that more favorable reaction chemistry (such as coupling) can be made possible in a separate reactor where, unlike in an in situ upgrading reactor, one does not have to deal with catalyst mixing with biomass char and ash, which pose challenges to catalyst performance and maintenance. Natural gas was used for hydrogen production, but only when off gases from the process was not sufficient to meet the needs; natural gas consumption is insignificant in both the in situ and ex situ base cases. Heat produced from the burning of char, coke, and off-gases allows for the production of surplus electricity which is sold to the grid allowing a reduction of approximately 5¢/GGE in the MFSP.

  12. The “Bringing into Cultivation” Phase of the Plant Domestication Process and Its Contributions to In Situ Conservation of Genetic Resources in Benin

    OpenAIRE

    Vodouhè, R.; Dansi, A.

    2012-01-01

    All over the world, plant domestication is continually being carried out by local communities to support their needs for food, fibre, medicine, building materials, etc. Using participatory rapid appraisal approach, 150 households were surveyed in 5 villages selected in five ethnic groups of Benin, to investigate the local communities’ motivations for plant domestication and the contributions of this process to in situ conservation of genetic resources. The results indicated differences in pla...

  13. Pyrolysis as a key process in biomass combustion and thermochemical conversion

    Directory of Open Access Journals (Sweden)

    Gvero Petar M.

    2016-01-01

    Full Text Available Biomass is a fuel with a highly volatile content and due to that, pyrolysis as a part of the combustion process, has a dominant role in the overall process development, as well as on final products and the process efficiency. It is of key importance to investigate the influence of the process parameters; as temperature, furnace/reactor environment, fuel properties, type, particle size, geometry, and the structure of the pyrolysis process has an influence regards the design of the combustion/pyrolysis equipment and the final products of the processes. This paper gives some results of the investigation’s related to this problem, mainly focussing on wooden biomass as the most important biomass type, as well as a comparison with relevant documented literature. Besides that, pyrolysis based technologies are one of the key directions in synthetic fuels production based on biomass. Biomass pyrolysis process parameters are crucial in reactor design as well as the quantity and quality of the final products. This paper provides discussion dedicated to this aspect with a focus on slow pyrolysis, targeting charcoal as the key product, and fast pyrolysis, targeting synthetic gas as the key product.

  14. Direct observation of the binding process between protein and quantum dots by in situ surface plasmon resonance measurements

    Energy Technology Data Exchange (ETDEWEB)

    Xiao Qi; Zhou Bo; Tian Fangfang; Ge Yushu; Liu Xiaorong; Liu Yi [State Key Laboratory of Virology, College of Chemistry and Molecular Science, Wuhan University, Wuhan 430072 (China); Huang Shan; Guan Hongliang; He Zhike, E-mail: prof.liuyi@263.ne [Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072 (China)

    2009-08-12

    A layer-by-layer surface decoration technique has been developed to anchor quantum dots (QDs) onto a gold substrate and an in situ surface plasmon resonance technique has been used to study interactions between the QDs and different proteins. Direct observation of the binding of the protein onto the QDs and the kinetics of the adsorption and dissociation of different proteins on the QDs has been achieved. This would be helpful for the identification of particle-associated proteins and may offer a fundamental prerequisite for nanobiology, nanomedicine and nanotoxicology. The combination of the novel layer-by-layer surface modification method and in situ surface plasmon resonance would be powerful in studying biological systems such as DNA and cells.

  15. In situ NIR spectroscopy monitoring of plasmid production processes effect of producing strain, medium composition and the cultivation strategy

    OpenAIRE

    Lopes, Marta B.; Gonçalves, Geisa A. L.; Felício-Silva, Daniel; Prather, Kristala L. J.; Monteiro, Gabriel; Prazeres, Duarte M. F.; Calado, Cecília Ribeiro da Cruz

    2015-01-01

    BACKGROUNDWhile the pharmaceutical industry keeps an eye on plasmid DNA production for new generation gene therapies, real-time monitoring techniques for plasmid bioproduction are as yet unavailable. This work shows the possibility of in situ monitoring of plasmid production in Escherichia coli cultures using a near infrared (NIR) fiber optic probe. RESULTSPartial least squares (PLS) regression models based on the NIR spectra were developed for predicting bioprocess critical variables su...

  16. HTR combustion head end comparison of the shaft furnace and fluidized bed processes

    Energy Technology Data Exchange (ETDEWEB)

    Boehnert, R.; Kaiser, G.; Pirk, H.; Tillessen, U.

    1975-01-15

    Two methods are described for the combustion of the graphite of HTR fuel elements, a sufficient description of the principles being given to permit an understanding of the processes. The present state of the technology of the two processes is then compared on the basis of the results obtained at Gulf General Atomic. Finally, the possibilities of further development are examined using a pilot plant designed to deliver a reactor power of 7000 MWe as the basis. The present report is a collection of facts. It contains neither an evaluation nor a recommendation. A summarized comparison of the state of the technology and the possibilities of development is given in tabular form.

  17. Effects of Fuel Quantity on Soot Formation Process for Biomass-Based Renewable Diesel Fuel Combustion

    KAUST Repository

    Jing, Wei

    2016-12-01

    Soot formation process was investigated for biomass-based renewable diesel fuel, such as biomass to liquid (BTL), and conventional diesel combustion under varied fuel quantities injected into a constant volume combustion chamber. Soot measurement was implemented by two-color pyrometry under quiescent type diesel engine conditions (1000 K and 21% O2 concentration). Different fuel quantities, which correspond to different injection widths from 0.5 ms to 2 ms under constant injection pressure (1000 bar), were used to simulate different loads in engines. For a given fuel, soot temperature and KL factor show a different trend at initial stage for different fuel quantities, where a higher soot temperature can be found in a small fuel quantity case but a higher KL factor is observed in a large fuel quantity case generally. Another difference occurs at the end of combustion due to the termination of fuel injection. Additionally, BTL flame has a lower soot temperature, especially under a larger fuel quantity (2 ms injection width). Meanwhile, average soot level is lower for BTL flame, especially under a lower fuel quantity (0.5 ms injection width). BTL shows an overall low sooting behavior with low soot temperature compared to diesel, however, trade-off between soot level and soot temperature needs to be carefully selected when different loads are used.

  18. Effects of aqueous effluents from in situ fossil fuel processing technologies on aquatic systems. Annual progress report, January 1-December 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, H.L.

    1980-01-04

    This is the third annual progress report for a continuing EPA-DOE jointly funded project to evaluate the effects of aqueous effluents from in situ fossil-fuel processing technologies on aquatic biota. The project is organized into four project tasks: (1) literature review; (2) process water screening; (3) methods development; and (4) recommendations. Our Bibliography of aquatic ecosystem effects, analytical methods and treatment technologies for organic compounds in advanced fossil-fuel processing effluents was submitted to the EPA for publication. The bibliography contains 1314 citations indexed by chemicals, keywords, taxa and authors. We estimate that the second bibliography volume will contain approximately 1500 citations and be completed in February. We compiled results from several laboratories of inorganic characterizations of 19 process waters: 55 simulated in situ oil-shale retort waters; and Hanna-3, Hanna-4B 01W and Lawrence Livermore Hoe Creek underground coal gasification condenser waters. These process waters were then compared to a published summary of the analyses from 18 simulated in situ oil-shale retort waters. We completed this year 96-h flow-through toxicity bioassays with fathead minnows and rainbow trout and 48-h flow-through bioassays with Daphnia pulicaria exposed to 5 oil-shale process waters, 1 tar-sand process water, 2 underground coal gasification condenser waters, 1 post-gasification backflood condenser water, as well as 2 bioassays with fossil-fuel process water constituents. The LC/sub 50/ toxicity values for these respective species when exposed to these waters are given in detail. (LTN)

  19. Bacterial-fungal interactions enhance power generation in microbial fuel cells and drive dye decolourisation by an ex situ and in situ electro-Fenton process.

    Science.gov (United States)

    Fernández de Dios, María Ángeles; del Campo, Araceli González; Fernández, Francisco Jesús; Rodrigo, Manuel; Pazos, Marta; Sanromán, María Ángeles

    2013-11-01

    In this work, the potential for sustainable energy production from wastes has been exploited using a combination fungus-bacterium in microbial fuel cell (MFC) and electro-Fenton technology. The fungus Trametes versicolor was grown with Shewanella oneidensis so that the bacterium would use the networks of the fungus to transport the electrons to the anode. This system generated stable electricity that was enhanced when the electro-Fenton reactions occurred in the cathode chamber. This configuration reached a stable voltage of approximately 1000 mV. Thus, the dual benefits of the in situ-designed MFC electro-Fenton, the simultaneous dye decolourisation and the electricity generation, were demonstrated. Moreover, the generated power was effectively used to drive an ex situ electro-Fenton process in batch and continuous mode. This newly developed MFC fungus-bacterium with an in situ electro-Fenton system can ensure a high power output and a continuous degradation of organic pollutants.

  20. Microstructure Evolution and Mechanical Properties of Al-TiB₂/TiC In Situ Aluminum-Based Composites during Accumulative Roll Bonding (ARB) Process.

    Science.gov (United States)

    Nie, Jinfeng; Wang, Fang; Li, Yusheng; Cao, Yang; Liu, Xiangfa; Zhao, Yonghao; Zhu, Yuntian

    2017-01-25

    In this study, a kind of Al-TiB₂/TiC in situ composite was successfully prepared using the melt reaction method and the accumulative roll-bonding (ARB) technique. The microstructure evolution of the composites with different deformation treatments was characterized using field emission scanning electron microscopy (FESEM) and a transmission electron microscope (TEM). The mechanical properties of the Al-TiB₂/TiC in situ composite were also studied with tensile and microhardness tests. It was found that the distribution of reinforcement particles becomes more homogenous with an increasing ARB cycle. Meanwhile, the mechanical properties showed great improvement during the ARB process. The ultimate tensile strength (UTS) and microhardness of the composites were increased to 173.1 MPa and 63.3 Hv after two ARB cycles, respectively. Furthermore, the strengthening mechanism of the composite was analyzed based on its fracture morphologies.

  1. Microstructure Evolution and Mechanical Properties of Al-TiB2/TiC In Situ Aluminum-Based Composites during Accumulative Roll Bonding (ARB) Process

    Science.gov (United States)

    Nie, Jinfeng; Wang, Fang; Li, Yusheng; Cao, Yang; Liu, Xiangfa; Zhao, Yonghao; Zhu, Yuntian

    2017-01-01

    In this study, a kind of Al-TiB2/TiC in situ composite was successfully prepared using the melt reaction method and the accumulative roll-bonding (ARB) technique. The microstructure evolution of the composites with different deformation treatments was characterized using field emission scanning electron microscopy (FESEM) and a transmission electron microscope (TEM). The mechanical properties of the Al-TiB2/TiC in situ composite were also studied with tensile and microhardness tests. It was found that the distribution of reinforcement particles becomes more homogenous with an increasing ARB cycle. Meanwhile, the mechanical properties showed great improvement during the ARB process. The ultimate tensile strength (UTS) and microhardness of the composites were increased to 173.1 MPa and 63.3 Hv after two ARB cycles, respectively. Furthermore, the strengthening mechanism of the composite was analyzed based on its fracture morphologies. PMID:28772467

  2. Simulation of sub-micron particle formation and growth during combustion processes

    Institute of Scientific and Technical Information of China (English)

    WEI Feng; ZHANG Junying; ZHENG Chuguang

    2005-01-01

    Sub-micron particle formation and growth during combustion processes is very complex because of its strong uncertainty and randomness. A model to simulate the sub-micron particle formation and growth during the combustion process is developed based on the gas kinetic theory and is expressed by the vapor concentration changes and particle loading changes, which reflects effect characteristics of different mechanism (nucleation, condensation and coagulation) in particle formation processes. The developed characteristic time is used to token the three mechanisms. It is thought that environmental temperature and pressure, vapor temperature and critical pressure are important factors influencing the sub-micron particle formation and growth. The sub-micron particle formation processes under different conditions are studied and the effect characteristics of these mechanisms are analyzed, which show that the nucleation, condensation,and coagulation occur simultaneously during the sub-micron particle formation and growth process. Nucleation contributes to the sub-micron particle formation, while condensation and coagulation is helpful to the growth of the particle size.

  3. Emission of volatile organic compounds from domestic coal stove with the actual alternation of flaming and smoldering combustion processes.

    Science.gov (United States)

    Liu, Chengtang; Zhang, Chenglong; Mu, Yujing; Liu, Junfeng; Zhang, Yuanyuan

    2017-02-01

    Volatile organic compounds (VOCs) emissions from the chimney of a prevailing domestic stove fuelled with raw bituminous coal were measured under flaming and smoldering combustion processes in a farmer's house. The results indicated that the concentrations of VOCs quickly increased after the coal loading and achieved their peak values in a few minutes. The peak concentrations of the VOCs under the smoldering combustion process were significantly higher than those under the flaming combustion process. Alkanes accounted for the largest proportion (43.05%) under the smoldering combustion, followed by aromatics (28.86%), alkenes (21.91%), carbonyls (5.81%) and acetylene (0.37%). The emission factors of the total VOCs under the smoldering combustion processes (5402.9 ± 2031.8 mg kg(-1)) were nearly one order of magnitude greater than those under the flaming combustion processes (559.2 ± 385.9 mg kg(-1)). Based on the VOCs emission factors obtained in this study and the regional domestic coal consumption, the total VOCs emissions from domestic coal stoves was roughly estimated to be 1.25 × 10(8) kg a(-1) in the Beijing-Tianjin-Hebei region. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Dry Sliding Wear Behavior of A356 Alloy/Mg2Sip Functionally Graded in-situ Composites: Effect of Processing Conditions

    Directory of Open Access Journals (Sweden)

    S.C. Ram

    2016-09-01

    Full Text Available In present study, the effect of dry sliding wear conditions of A356 alloy/Mg2Sip functionally graded in-situ composites developed by centrifugal casting method has been studied. A pure commercial A356 alloy (Al–7.5Si–0.3Mg was selected to be the matrix of the composites and primary Mg2Sip reinforcing particles were formed by in-situ chemical reaction with an average grain size of 40-47.8 µm. The Al–(Mg2Sip functionally graded metal matrix composites (FGMMC’s were synthesized by centrifugal casting technique with radial geometry, using two different mould rotating speeds ( 1200 and 1600 rpm. The X-ray diffraction (XRD characterization technique was carried out to confirm the in-situ formed Mg2Si particles in composites. Optical microscopy examination was carried out to reveals the grain refinement of Al-rich grains due to in-situ formed Mg2Si particles. Scanning electron microscope (SEM and Energy dispersive X-ray spectroscopy (EDS techniques were carried out to reveal the distribution of phases, morphological characteristics and confirmation of primary Mg2Si particles in the matrix. The sliding wear behavior was studied using a Pin-on-Disc set-up machine with sliding wear parameters: effect of loads (N, effect of sliding distances (m and effect of Mg on wear at room temperature with a high-carbon chromium steel disc (HRC-64 as counter surfaces. A good correlation was evidenced between the dry sliding behaviour of functionally graded in-situ composites and the distribution of Mg2Si reinforcing particles. Beside the above processing conditions, the dominant wear mechanisms of functionally graded in-situ composites have been correlated with the microstructures. The hardness and wear resistance properties of these composites increase with increasing volume percent of reinforced primary Si/Mg2Si particles toward inner zone of cast cylindrical shapes. The objective of this works was to study the tribological characteristics under dry sliding

  5. Process simulation and maximization of energy output in chemical-looping combustion using ASPEN plus

    Directory of Open Access Journals (Sweden)

    Xiao Zhang, Subhodeep Banerjee, Ling Zhou, Ramesh Agarwal

    2015-01-01

    Full Text Available Chemical-looping combustion (CLC is currently considered as a leading technology for reducing the economic cost of CO2 capture. In this paper, several process simulations of chemical-looping combustion are conducted using the ASPEN Plus software. The entire CLC process from the beginning of coal gasification to the reduction and oxidation of the oxygen carrier is modeled and validated against experimental data. The energy balance of each major component of the CLC process, e.g., the fuel and air reactors and air/flue gas heat exchangers is examined. Different air flow rates and oxygen carrier feeding rates are used in the simulations to obtain the optimum ratio of coal, air, and oxygen carrier that produces the maximum power. Two scaled-up simulations are also conducted to investigate the influence of increase in coal feeding on power generation. It is demonstrated that the optimum ratio of coal, air supply, and oxygen carrier for maximum power generation remains valid for scaled-up cases with substantially larger coal feeding rates; the maximum power generation scales up linearly by using the process simulation models in ASPEN Plus. The energy output from four different types of coals is compared, and the optimum ratio of coal, air supply and oxygen carrier for maximum power generation for each type of coal is determined.

  6. Risk analysis of a biomass combustion process using MOSAR and FMEA methods.

    Science.gov (United States)

    Thivel, P-X; Bultel, Y; Delpech, F

    2008-02-28

    Thermal and chemical conversion processes that convert in energy the sewage sludge, pasty waste and other pre-processed waste are increasingly common, for economic and ecological reasons. Fluidized bed combustion is currently one of the most promising methods of energy conversion, since it burns biomass very efficiently, and produces only very small quantities of sulphur and nitrogen oxides. The hazards associated with biomass combustion processes are fire, explosion and poisoning from the combustion gases (CO, etc.). The risk analysis presented in this paper uses the MADS-MOSAR methodology, applied to a semi-industrial pilot scheme comprising a fluidization column, a conventional cyclone, two natural gas burners and a continuous supply of biomass. The methodology uses a generic approach, with an initial macroscopic stage where hazard sources are identified, scenarios for undesired events are recognized and ranked using a grid of SeverityxProbability and safety barriers suggested. A microscopic stage then analyzes in detail the major risks identified during the first stage. This analysis may use various different tools, such as HAZOP, FMEA, etc.: our analysis is based on FMEA. Using MOSAR, we were able to identify five subsystems: the reactor (fluidized bed and centrifuge), the fuel and biomass supply lines, the operator and the environment. When we drew up scenarios based on these subsystems, we found that malfunction of the gas supply burners was a common trigger in many scenarios. Our subsequent microscopic analysis, therefore, focused on the burners, looking at the ways they failed, and at the effects and criticality of those failures (FMEA). We were, thus, able to identify a number of critical factors such as the incoming gas lines and the ignition electrode.

  7. Methodology for processing pressure traces used as inputs for combustion analyses in diesel engines

    Science.gov (United States)

    Rašić, Davor; Vihar, Rok; Žvar Baškovič, Urban; Katrašnik, Tomaž

    2017-05-01

    This study proposes a novel methodology for designing an optimum equiripple finite impulse response (FIR) filter for processing in-cylinder pressure traces of a diesel internal combustion engine, which serve as inputs for high-precision combustion analyses. The proposed automated workflow is based on an innovative approach of determining the transition band frequencies and optimum filter order. The methodology is based on discrete Fourier transform analysis, which is the first step to estimate the location of the pass-band and stop-band frequencies. The second step uses short-time Fourier transform analysis to refine the estimated aforementioned frequencies. These pass-band and stop-band frequencies are further used to determine the most appropriate FIR filter order. The most widely used existing methods for estimating the FIR filter order are not effective in suppressing the oscillations in the rate- of-heat-release (ROHR) trace, thus hindering the accuracy of combustion analyses. To address this problem, an innovative method for determining the order of an FIR filter is proposed in this study. This method is based on the minimization of the integral of normalized signal-to-noise differences between the stop-band frequency and the Nyquist frequency. Developed filters were validated using spectral analysis and calculation of the ROHR. The validation results showed that the filters designed using the proposed innovative method were superior compared with those using the existing methods for all analyzed cases. Highlights • Pressure traces of a diesel engine were processed by finite impulse response (FIR) filters with different orders • Transition band frequencies were determined with an innovative method based on discrete Fourier transform and short-time Fourier transform • Spectral analyses showed deficiencies of existing methods in determining the FIR filter order • A new method of determining the FIR filter order for processing pressure traces was

  8. ACACIA Project – Development of a Post-Combustion CO2 Capture Process. Case of the DMXTM Process

    Directory of Open Access Journals (Sweden)

    Gomez A.

    2014-11-01

    Full Text Available The objective of the ACACIA project was to develop processes for post-combustion CO2 capture at a lower cost and with a higher energetic efficiency than first generation processes using amines such as MonoEthanolAmine (MEA which are now considered for the first Carbon Capture and Storage (CCS demonstrators. The partners involved in this project were: Rhodia (Solvay since then, Arkema, Lafarge, GDF SUEZ, Veolia Environnement, IFP Energies nouvelles, IRCE Lyon, LMOPS, LTIM, LSA Armines. To validate the relevance of the breakthrough processes studied in this project, techno-economic evaluations were carried out with comparison to the reference process using a 30 wt% MEA solvent. These evaluation studies involved all the industrial partners of the project, each partner bringing specific cases of CO2 capture on their industrial facilities. From these studies, only the process using demixing solvent, DMXTM, developed by IFPEN appears as an alternative solution to the MEA process.

  9. PEDOT:PSS-Based Piezo-Resistive Sensors Applied to Reinforcement Glass Fibres for in Situ Measurement during the Composite Material Weaving Process

    Directory of Open Access Journals (Sweden)

    Damien Soulat

    2013-08-01

    Full Text Available The quality of fibrous reinforcements used in composite materials can be monitored during the weaving process. Fibrous sensors previously developed in our laboratory, based on PEDOT:PSS, have been adapted so as to directly measure the mechanical stress on fabrics under static or dynamic conditions. The objective of our research has been to develop new sensor yarns, with the ability to locally detect mechanical stresses all along the warp or weft yarn. This local detection is undertaken inside the weaving loom in real time during the weaving process. Suitable electronic devices have been designed in order to record in situ measurements delivered by this new fibrous sensor yarn.

  10. PEDOT:PSS-based piezo-resistive sensors applied to reinforcement glass fibres for in situ measurement during the composite material weaving process.

    Science.gov (United States)

    Trifigny, Nicolas; Kelly, Fern M; Cochrane, Cédric; Boussu, François; Koncar, Vladan; Soulat, Damien

    2013-08-16

    The quality of fibrous reinforcements used in composite materials can be monitored during the weaving process. Fibrous sensors previously developed in our laboratory, based on PEDOT:PSS, have been adapted so as to directly measure the mechanical stress on fabrics under static or dynamic conditions. The objective of our research has been to develop new sensor yarns, with the ability to locally detect mechanical stresses all along the warp or weft yarn. This local detection is undertaken inside the weaving loom in real time during the weaving process. Suitable electronic devices have been designed in order to record in situ measurements delivered by this new fibrous sensor yarn.

  11. In situ analysis of electrocrystallization process of metal electrodeposition with confocal energy dispersive X-ray diffraction based on polycapillary X-ray optics

    Energy Technology Data Exchange (ETDEWEB)

    Li, Fangzuo; Liu, Zhiguo [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Sun, Tianxi, E-mail: stx@bnu.edu.cn [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Yang, Chaolin; Sun, Weiyuan; Sun, Xuepeng [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Ma, Yongzhong [Center for Disease Control and Prevention of Beijing, Beijing 100013 (China); Ding, Xunliang [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2015-06-11

    The confocal energy dispersive X-ray diffraction (EDXRD) based on a polycapillary focusing X-ray lens (PFXRL) in excitation channel and a polycapillary parallel X-ray lens (PPXRL) in detection channel was presented to study the electrocrystallization process of metal electrodeposition. The input focal spot of the PPXRL and the output focal spot of the PFXRL was adjusted in a confocal configuration, and only the X-rays from the volume overlapped by the two foci could be accordingly detected by the detector. The experimental results demonstrated the confocal EDXRD could be used to in situ real-time analysis of electrochemical crystal growth process.

  12. Fundamental phenomena on fuel decomposition and boundary layer combustion processes with applications to hybrid rocket motors

    Science.gov (United States)

    Kuo, Kenneth K.; Lu, Y. C.; Chiaverini, Martin J.; Harting, George C.

    1994-11-01

    An experimental study on the fundamental processes involved in fuel decomposition and boundary layer combustion in hybrid rocket motors is being conducted at the High Pressure Combustion Laboratory of the Pennsylvania State University. This research should provide a useful engineering technology base in the development of hybrid rocket motors as well as a fundamental understanding of the complex processes involved in hybrid propulsion. A high pressure slab motor has been designed and manufactured for conducting experimental investigations. Oxidizer (LOX or GOX) supply and control systems have been designed and partly constructed for the head-end injection into the test chamber. Experiments using HTPB fuel, as well as fuels supplied by NASA designated industrial companies will be conducted. Design and construction of fuel casting molds and sample holders have been completed. The portion of these items for industrial company fuel casting will be sent to the McDonnell Douglas Aerospace Corporation in the near future. The study focuses on the following areas: observation of solid fuel burning processes with LOX or GOX, measurement and correlation of solid fuel regression rate with operating conditions, measurement of flame temperature and radical species concentrations, determination of the solid fuel subsurface temperature profile, and utilization of experimental data for validation of a companion theoretical study (Part 2) also being conducted at PSU.

  13. Fundamental phenomena on fuel decomposition and boundary layer combustion processes with applications to hybrid rocket motors

    Science.gov (United States)

    Kuo, Kenneth K.; Lu, Y. C.; Chiaverini, Martin J.; Harting, George C.

    1994-01-01

    An experimental study on the fundamental processes involved in fuel decomposition and boundary layer combustion in hybrid rocket motors is being conducted at the High Pressure Combustion Laboratory of the Pennsylvania State University. This research should provide a useful engineering technology base in the development of hybrid rocket motors as well as a fundamental understanding of the complex processes involved in hybrid propulsion. A high pressure slab motor has been designed and manufactured for conducting experimental investigations. Oxidizer (LOX or GOX) supply and control systems have been designed and partly constructed for the head-end injection into the test chamber. Experiments using HTPB fuel, as well as fuels supplied by NASA designated industrial companies will be conducted. Design and construction of fuel casting molds and sample holders have been completed. The portion of these items for industrial company fuel casting will be sent to the McDonnell Douglas Aerospace Corporation in the near future. The study focuses on the following areas: observation of solid fuel burning processes with LOX or GOX, measurement and correlation of solid fuel regression rate with operating conditions, measurement of flame temperature and radical species concentrations, determination of the solid fuel subsurface temperature profile, and utilization of experimental data for validation of a companion theoretical study (Part 2) also being conducted at PSU.

  14. Study on the combustion behavior of high impact polystyrene nanocomposites produced by different extrusion processes

    Directory of Open Access Journals (Sweden)

    2008-08-01

    Full Text Available The combustion behavior of a blend made of high impact polystyrene (HIPS with sodium montmorillonite (MMT-Na+ and triphenyl phosphite (TPP, as a halogen-free flame retardant, is analyzed in detail in this work. The blend is processed through various extrusion methods aimed to improve clay dispersion. The UL94 method in vertical position, oxygen index and cone calorimetric measurements assess HIPS blend behavior in combustion. TGA, FTIR, SEM and X-ray measurements, together with mechanical and rheological tests evaluate the thermal degradation, morphology, intercalation and degree of dispersion of particles. The use of a static-mixing die placed at the extreme of a single screw extruder improves clay platelets distribution and reduces the peak heat release rate better than employing a twin screw extrusion process. In addition, mechanical and rheological properties are affected substantially by changing the extrusion process. A correlation between clay dispersion and HIPS fire retardant properties is found, as the peak heat release rate decreases with good clay dispersion in cone calorimetric tests.

  15. Polymer particles filled with multiple colloidal silica via in situ sol-gel process and their thermal property

    Science.gov (United States)

    Byun, Hongsik; Hu, Jiayun; Pakawanit, Phakkhananan; Srisombat, Laongnuan; Kim, Jun-Hyun

    2017-01-01

    The in situ formation of dielectric silica (SiO2) particles was carried out in the presence of temperature-responsive poly(N-isopropylacrylamide) particles. Unlike the typical sol-gel method used to prepare various SiO2 particles, the highly uniform growth of SiO2 particles was achieved within the cross-linked polymer particles (i.e., the polymer particles were filled with the SiO2 particles) simply by utilizing interfacial interactions, including the van der Waals attractive force and hydrogen bonding in nanoscale environments. The structural and morphological features as well as the thermal behaviors of these composites were thoroughly examined by electron microscopes, dynamic light scattering, and thermal analyzers. In particular, the thermal properties of these composites were completely different from the bare polymer, SiO2 particles, and their mixtures, which clearly suggested the successful incorporation of multiple SiO2 particles within the cross-linked polymer particles. Similarly, titanium oxide (TiO2) particles were easily embedded within the polymer particle template which exhibited improved overall properties. As a whole, understanding in situ formation of nanoscale inorganic particles within polymer particle templates can allow for designing novel composite materials possessing enhanced chemical and physical properties.

  16. Enhanced removal of sodium salts supported by in-situ catalyst synthesis in a supercritical water oxidation process.

    Science.gov (United States)

    Takahashi, F; Sun, Z R; Fukushi, K; Oshima, Y; Yamamoto, K

    2012-01-01

    For practical applications of supercritical water oxidation to wastewater treatment, the deposition of inorganic salts in supercritical phase must be controlled to prevent a reactor from clogging. This study investigated enhanced removal of sodium salts with titanium particles, serving as a salt trapper and a catalyst precursor, and sodium recovery by sub-critical water. When Na(2)CO(3) was tested as a model salt, sodium removal efficiency was higher than theoretically maximum efficiency defined by Na(2)CO(3) solubility. The enhanced sodium removal resulted from in-situ synthesis of sodium titanate, which could catalyse acetic acid oxidation. The kinetics of sodium removal was described well by a diffusion mass-transfer model combined with a power law-type rate model of sodium titanate synthesis. Titanium particles showed positive effect on sodium removal in the case of NaOH, Na(2)SO(4) and Na(3)PO(4). However, they had negligible effect for NaCl and negative effect for Na(2)CrO(4), respectively. More than 99% of trapped sodium was recovered by sub-critical water except for Na(2)CrO(4). In contrast, sodium recovery efficiency remained less than 50% in the case of Na(2)CrO(4). Reused titanium particles showed the same performance for enhanced sodium removal. Enhanced salt removal supported by in-situ catalyst synthesis has great potential to enable both salt removal control and catalytic oxidation.

  17. The control of H2S in biogas using iron ores as in situ desulfurizers during anaerobic digestion process.

    Science.gov (United States)

    Zhou, Qiying; Jiang, Xia; Li, Xi; Jiang, Wenju

    2016-09-01

    In this study, five kinds of iron ores, limonite, hematite, manganese ore, magnetite and lava rock, were used as the in situ desulfurizers in the anaerobic digestion reactors to investigate their effects on controlling H2S in biogas. The results show that the addition of the five iron ores could significantly control the content of H2S in biogas, with the best performance for limonite. As limonite dosages increase (10-60 g/L), the contents of H2S in biogas were evidently decreased in the digesters with different initial sulfate concentrations (0-1000 mg/L). After the anaerobic digestion, the removed sulfur was mostly deposited on the surface of limonite. A possible mechanism of H2S control in biogas by limonite was proposed preliminarily, including adsorption, FeS precipitation, and Fe (III) oxidation. The results demonstrated that limonite was a promising in situ desulfurizer for controlling H2S in biogas with low cost and high efficiency.

  18. Coal Combustion Science. Quarterly progress report, October--December 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hardesty, D.R. [ed.; Baxter, L.L.; Davis, K.A.; Hurt, R.H.; Yang, N.Y.C.

    1996-02-01

    The objective of this work is to support the Office of Fossil Energy in executing research on coal combustion science. This project consists of basic research on coal combustion that supports both the Pittsburgh Energy Technology Center (PETC) Direct Utilization Advanced Research and Technology Development Program, and the International Energy Agency (IEA) Coal Combustion Science Project. Specific tasks include: Task 1--Kinetics and mechanisms of pulverized coal char combustion; and Task 2--deposit growth and property development in coal-fired furnaces. The objective of task 1 is to characterize the combustion behavior of selected US coals under conditions relevant to industrial pulverized coal-fired furnaces. Work is being done in four areas: (a) kinetics of heterogeneous fuel particle populations; (b) char combustion kinetics at high carbon conversion; (c) the role of particle structure and the char formation process in combustion and; (d) unification of the Sandia char combustion data base. The objectives of Task 2 are to provide a self-consistent database of simultaneously measured, time-resolved, ash deposit properties in well-controlled and well-defined environments and to provide analytical expressions that relate deposit composition and structure to deposit properties of immediate relevance to PETC`s Combustion 2000 program. The task include the development and use of diagnostics to monitor, in situ and in real time, deposit properties, including information on both the structure and composition of the deposits.

  19. Modified graphical autocatalytic set model of combustion process in circulating fluidized bed boiler

    Science.gov (United States)

    Yusof, Nurul Syazwani; Bakar, Sumarni Abu; Ismail, Razidah

    2014-07-01

    Circulating Fluidized Bed Boiler (CFB) is a device for generating steam by burning fossil fuels in a furnace operating under a special hydrodynamic condition. Autocatalytic Set has provided a graphical model of chemical reactions that occurred during combustion process in CFB. Eight important chemical substances known as species were represented as nodes and catalytic relationships between nodes are represented by the edges in the graph. In this paper, the model is extended and modified by considering other relevant chemical reactions that also exist during the process. Catalytic relationship among the species in the model is discussed. The result reveals that the modified model is able to gives more explanation of the relationship among the species during the process at initial time t.

  20. Combustion and structure formation in SHS processes under microgravity conditions: SHS plans for microgravity experiments

    Science.gov (United States)

    Merzhanov, A. G.

    1995-01-01

    This paper outlines ISMAN suggestions for the joint NASA-RSA project 'Combustion and Structure formation in SHS Processes under Microgravity Conditions'. The basic ideas of this work naturally follow from our almost 30-year experience in the field of SHS. As a matter of fact, we have already obtained some results in the following two directions closely related to the microgravity problem. One is the studies on SHS processes in the field of centrifugal forces. These studies aimed at the intensification of gravity-sensitive SHS processes in multicomponent highly caloric systems forming melts at high overloads (up to 2000 g). In other words, these studies had the objectives that are inverse to those in the microgravity studies. The second group of results directly relates to the microgravity problem and the project under consideration. These experiments played the important role in establishing links between SHS and microgravity.

  1. Analysis of Combustion Process of Sewage Sludge in Reference to Coals and Biomass

    Science.gov (United States)

    Środa, Katarzyna; Kijo-Kleczkowska, Agnieszka

    2016-06-01

    Production of sewage sludge is an inseparable part of the treatment process. The chemical and sanitary composition of sewage sludge flowing into the treatment plant is a very important factor determining the further use of the final product obtained in these plants. The sewage sludge is characterized by heterogeneity and multi-components properties, because they have characteristics of the classical and fertilizer wastes and energetic fuels. The thermal utilization of sewage sludge is necessary due to the unfavorable sanitary characteristics and the addition of the industrial sewage. This method ensures use of sewage sludge energy and return of expenditure incurred for the treatment of these wastes and their disposal. Sewage sludge should be analyzed in relation to conventional fuels (coals and biomass). They must comply with the applicable requirements, for example by an appropriate degree of dehydration, which guarantee the stable and efficient combustion. This paper takes the issue of the combustion process of the different sewage sludge and their comparison of the coal and biomass fuels.

  2. Obtaining zeolites from slags and ashes from a waste combustion plant in an autoclave process

    Directory of Open Access Journals (Sweden)

    Grela Agnieszka

    2017-01-01

    Full Text Available Waste combustion is associated with the generation of post-processing solid products – waste such as slag and ash. One of the promising technologies in waste management and processing is the synthesis of zeolites and other materials exhibiting sorption properties. The aim of this study was to characterise and assess the physicochemical properties of the waste and the products synthesised from it. This paper presents the possibility of synthesis zeolites from the slag and ash from two waste combustion plants. The investigated waste is classified as hazardous waste and denoted by the EWC code 190111*. The paper presents the results of physicochemical studies of these materials. As a result of synthesis in an autoclave at 140°C with the use of 2 M NaOH, and other compounds, such zeolite forms as chabazite and sodalite were obtained. Textural studies and ion-exchange capacity investigations carried out allowed characterisation of the sorption properties of the materials. It was found that the materials obtained are characterised by the BET specific surface areas of 25.45 m2/g and 16.79 m2/g.

  3. Study on drying and combustion process in 8rate-CFB incinerator

    Institute of Scientific and Technical Information of China (English)

    LI QingHai; ZHANG YanGuo; CHEN MeiQian; MENG AiHong; CHEN ChangHe

    2009-01-01

    The drying and combustion process in the combined grate and circulating fiuidized bed (grate-CFB)municipal solid waste (MSW) incinerator was investigated experimentally and mathematically. The drying grate bed was simulated by a muffle furnace, which could be controlled at a constant tempera-ture level. The kind of wastes, thickness of waste layer fed and temperature were chosen as the ad-justable parameters to study their effect on the drying process. The experimental results indicated that the hydrophilic wastes were more difficult to be dried than the hydrophobic wastes. The higher the temperature is the easier the waste is to be dried. The thinner waste layer is favorable to drying the waste. The pyrolysis experiment in the furnace showed that the higher temperature level could reduce the conversion rate of carbon to carbon monoxide. The semi-empirical mathematical model that in-cluded the bed material distribution subrnodel, volatile matter release submodel, carbon particle combustion submodel and so on was proposed. A 260 t/d grate-CFB incinerator was modeled and the model predicted bulk density agreed with the measured value from industrial field test. The predicted flue gas (e.g. CO2, CO) concentration deviated slightly from the industrial test data. The parameters and variables used in the model were determined by the experiments or practical field test. This model can be used to design the grate-CFB incinerator and guide its operation.

  4. Coal combustion science. Quarterly progress report, April 1993--June 1993

    Energy Technology Data Exchange (ETDEWEB)

    Hardesty, D.R. [ed.

    1994-05-01

    This document is a quarterly status report of the Coal Combustion Science Project that is being conducted at the Combustion Research Facility, Sandia National Laboratories. The information reported is for Apr-Jun 1993. The objective of this work is to support the Office of Fossil Energy in executing research on coal combustion science. This project consists of basic research on coal combustion that supports both the PETC Direct Utilization Advanced Research and Technology Development Program, and the International Energy Agency Coal Combustion Science Project. The objective of the kinetics and mechanisms of pulverized coal char combustion task is to characterize the combustion behavior of selected US coals under conditions relevant to industrial pulverized coal-fired furnaces. Work is being done in four areas: kinetics of heterogeneous fuel particle populations; char combustion kinetics at high carbon conversion; the role of particle structure and the char formation process in combustion and; unification of the Sandia char combustion data base. This data base on the high temperature reactivities of chars from strategic US coals will permit identification of important fuel-specific trends and development of predictive capabilities for advanced coal combustion systems. The objective of the fate of inorganic material during coal combustion task is the establish a quantitative understanding of the mechanisms and rates of transformation, fragmentation, and deposition of inorganic material during coal combustion as a function of coal type, particle size and temperature, the initial forms and distribution of inorganic species in the unreacted coal, and the local gas temperature and composition. In addition, optical diagnostic capabilities are being developed for in situ, real-time detection of inorganic vapor species and surface species during ash deposition. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  5. In-Situ Chemical Dynamics and Phase Mapping Under Steep Thermal Gradients Using Time-Resolved and Spatially Resolved X-Ray Diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Wong, J.; Larson, E.M.; Holt, J.B.; Ressler, T.; Elmer, J.W.

    1999-09-17

    Time-resolved and spatially-resolved diffraction techniques have been developed recently to perform materials dynamics study in-situ extending into the time and spatial domain in high temperature processes. The applications of these methods to investigate the chemical dynamics of solid combustion reactions and to map phases and their transformation in fusion welds are exemplified in this paper.

  6. Agile dry etching of compound semiconductors for science-based manufacturing using in-situ process control

    Energy Technology Data Exchange (ETDEWEB)

    ASHBY,CAROL I.; VAWTER,GREGORY A.; BREILAND,WILLIAM G.; BRUSKAS,LARRY A.; WOODWORTH,JOSEPH R.; HEBNER,GREGORY A.

    2000-02-01

    In-situ optical diagnostics and ion beam diagnostics for plasma-etch and reactive-ion-beam etch (RIBE) tools have been developed and implemented on etch tools in the Compound Semiconductor Research Laboratory (CSRL). The optical diagnostics provide real-time end-point detection during plasma etching of complex thin-film layered structures that require precision etching to stop on a particular layer in the structure. The Monoetch real-time display and analysis program developed with this LDRD displays raw and filtered reflectance signals that enable an etch system operator to stop an etch at the desired depth within the desired layer. The ion beam diagnostics developed with this LDRD will permit routine analysis of critical ion-beam profile characteristics that determine etch uniformity and reproducibility on the RIBE tool.

  7. Study on the-Redox Process of Bilirubin and Biliverdin at Platinum Electrode by in Situ Spectroelectrochemistry

    Institute of Scientific and Technical Information of China (English)

    牛建军; 董绍俊

    1994-01-01

    The electrochemical redox behavior of bilirubin(BR Ⅳα),biliverdin(BV Ⅳα)and theiroxidized product bile-purpurin(Bi-Pu)have been studied by in situ spectroelectrochemical techniques,whichreveals that the transformation of BR Ⅳα■BV Ⅳα■Bi-Pu can be achieved by controlling poten-tials.The kinetic investigation has shown that the heterogeneous electron transfer reactions of the couples ofⅠ/Ⅱ and Ⅳ/Ⅲ were quasi-reversible and irreversible at a clean platinum electrode with the formal heteroge-neous electron transfer rate constants 1.5×10-4cm·s-1and 4.8×10-5cm·s-1,respectively.

  8. In situ protein secondary structure determination in ice: Raman spectroscopy-based process analytical tool for frozen storage of biopharmaceuticals.

    Science.gov (United States)

    Roessl, Ulrich; Leitgeb, Stefan; Pieters, Sigrid; De Beer, Thomas; Nidetzky, Bernd

    2014-08-01

    A Raman spectroscopy-based method for in situ monitoring of secondary structural composition of proteins during frozen and thawed storage was developed. A set of reference proteins with different α-helix and β-sheet compositions was used for calibration and validation in a chemometric approach. Reference secondary structures were quantified with circular dichroism spectroscopy in the liquid state. Partial least squares regression models were established that enable estimation of secondary structure content from Raman spectra. Quantitative secondary structure determination in ice was accomplished for the first time and correlation with existing (qualitative) protein structural data from the frozen state was achieved. The method can be used in the presence of common stabilizing agents and is applicable in an industrial freezer setup. Raman spectroscopy represents a powerful, noninvasive, and flexibly applicable tool for protein stability monitoring during frozen storage. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  9. Effect of Algae-Derived Biodiesel on Ignition Delay, Combustion Process and Emission

    Science.gov (United States)

    Kumaran, Mahendran; Khalid, Amir; Salleh, Hamidon; Razali, Azahari; Sapit, Azwan; Jaat, Norrizam; Sunar, Norshuhaila

    2016-11-01

    Algae oil methyl esters produced from algae oil were blended with diesel at various volumetric percentages to evaluate the variations in the fuel properties. Microalgae biodiesel production has received much interest in an effort for sustainable development as the microalgae seem to be an attractive way to produce the biodiesel due to their ability to accumulate lipids and their very high actual photosynthetic yields. Correlations between fuel properties, including the calorific heat, density, kinematic viscosity, and oxidation stability of the Algae oil-diesel blends, and the blending ratio of the algae biodiesel have been established. As a result, low blending ratio of the Algae oil with diesel was recommended up to 2vol % in comparison with other type of biodiesel-diesel blends. The objective of this research is to investigate effect of biodiesel blending ratio on ignition delay, combustion process and emission for different type of biodiesel. The combustion tests of the Algae-Derived biodiesel blends were performed in a Rapid Compression Machine (RCM). The combustion tests were carried out at injection pressure of 130 MPa and ambient temperature were varied between 750 K and 1100 K. The result from the experiment is compared with Palm-Oil biodiesel which are varied in biodiesel percentage from 5vol% to 15vol% and jatropha biodiesel. Higher ignition delay period were clearly observed with higher blending ratio. It seems that increasing blending ratio exhibits relatively weakens in fuel ignitibility and therefore prolongs the ignition delay of algae biodiesel. A2 had the lowest ignition delay period when compared with J2, B5, B10 and B15 due to lower density that present in A2 molecules.The concentration of carbon dioxide and nitrogen monoxide in the exhaust gas increased with higher blending ratio while the concentration of carbon monoxide and hydrocarbon decreased.

  10. Influence of process parameters on coal combustion performance. Review, experiments and engineering modeling

    Energy Technology Data Exchange (ETDEWEB)

    Lans, R.P. van der

    1997-04-01

    The objective of this study is to improve the understanding of nitrogen oxide formation and carbon burnout during the combustion of pulverized coal, and to contribute to addressing the potential of chemical engineering models for the prediction of furnace temperatures, NO emissions and the amount of carbon in ash. To this purpose, the effect of coal quality on NO and burnout has been investigated experimentally, a radiation heat balance has been developed based on a simple chemical engineering methodology, and a mixing study has been conducted in order to describe the near burner macro mixing in terms of a reactor configuration. The influence of coal type and process conditions on NO formation and carbon burnout has been investigated experimentally in a 400 MW{sub e} corner fired boiler with over fire air, a 350 MW{sub e} opposed fired boiler, and in a 160 kW{sub t} pilot scale test rig. Three different coals were fired in each of the furnaces as part of the activities in group 3 of the European Union JOULE 2 Extension project `Atmospheric Pressure Combustion of Pulverized Coal and Coal Based Blends for Power Generation`. On the pilot scale test both single stage and air staged tests were performed. A simple, one-dimensional combustion and radiation heat transfer model has been developed for the furnace of full scale boilers. The model has been applied to the two boilers mentioned above, and is validated against measured temperatures and carbon in ash concentrations. A mixing study has been performed in order to initiate an investigation of the potential of chemical engineering models to predict NO from pulverized fuel burners. (EG) 11 refs.

  11. Application of NMR spectroscopy and multidimensional imaging to the gelcasting process and in-situ real-time monitoring of cross-linking polyacrylamide gels

    Energy Technology Data Exchange (ETDEWEB)

    Ahuja, S.; Dieckman, S.L.; Gopalsami, N. [and others

    1995-04-01

    In the gelcasting process, a slurry of ceramic powder in a solution of organic monomers is cast in a mold. The process is different from injection molding in that it separates mold-filling from setting during conversion of the ceramic slurry to a formed green part. In this work, NMR spectroscopy and imaging have been conducted for in-situ monitoring of the gelation process and for mapping the polymerization. {sup 1}H nuclear magnetic resonance spectra have been obtained during polymerization of a premix of soluble reactive methacrylamide (monomer) and N, N`-methylene bisacrylamide (cross-linking molecules). The premix was polymerized by adding ammonium persulfate (initiator) and tetramethyl-ethylene-diamine (accelerator) to form long-chain, cross-linked polymers. The time-varying spin-lattice relaxation times T{sub 1} during polymerization have been studied at 25 and 35{degrees}C, and the variation of spectra and T{sub 1} with respect to extent of polymerization has been determined. To verify homogeneous polymerization, multidimensional NMR imaging was utilized for in-situ monitoring of the process. The intensities from the images are modeled and the correspondence shows a direct extraction of T{sub 1} data from the images.

  12. Oxygen-enhanced combustion

    CERN Document Server

    Baukal, Charles E

    2013-01-01

    Combustion technology has traditionally been dominated by air/fuel combustion. However, two developments have increased the significance of oxygen-enhanced combustion-new technologies that produce oxygen less expensively and the increased importance of environmental regulations. Advantages of oxygen-enhanced combustion include less pollutant emissions as well as increased energy efficiency and productivity. Oxygen-Enhanced Combustion, Second Edition compiles information about using oxygen to enhance industrial heating and melting processes. It integrates fundamental principles, applications, a

  13. Ignition technique for an in situ oil shale retort

    Science.gov (United States)

    Cha, Chang Y.

    1983-01-01

    A generally flat combustion zone is formed across the entire horizontal cross-section of a fragmented permeable mass of formation particles formed in an in situ oil shale retort. The flat combustion zone is formed by either sequentially igniting regions of the surface of the fragmented permeable mass at successively lower elevations or by igniting the entire surface of the fragmented permeable mass and controlling the rate of advance of various portions of the combustion zone.

  14. Problems in Catalytic Oxidation of Hydrocarbons and Detailed Simulation of Combustion Processes

    Science.gov (United States)

    Xin, Yuxuan

    This dissertation research consists of two parts, with Part I on the kinetics of catalytic oxidation of hydrocarbons and Part II on aspects on the detailed simulation of combustion processes. In Part I, the catalytic oxidation of C1--C3 hydrocarbons, namely methane, ethane, propane and ethylene, was investigated for lean hydrocarbon-air mixtures over an unsupported Pd-based catalyst, from 600 to 800 K and under atmospheric pressure. In Chapter 2, the experimental facility of wire microcalorimetry and simulation configuration were described in details. In Chapter 3 and 4, the oxidation rate of C1--C 3 hydrocarbons is demonstrated to be determined by the dissociative adsorption of hydrocarbons. A detailed surface kinetics model is proposed with deriving the rate coefficient of hydrocarbon dissociative adsorption from the wire microcalorimetry data. In Part II, four fundamental studies were conducted through detailed combustion simulations. In Chapter 5, self-accelerating hydrogen-air flames are studied via two-dimensional detailed numerical simulation (DNS). The increase in the global flame velocity is shown to be caused by the increase of flame surface area, and the fractal structure of the flame front is demonstrated by the box-counting method. In Chapter 6, skeletal reaction models for butane combustion are derived by using directed relation graph (DRG) and DRG-aided sensitivity analysis (DRGASA), and uncertainty minimization by polynomial chaos expansion (MUM-PCE) mothodes. The dependence of model uncertainty is subjected to the completeness of the model. In Chapter 7, a systematic strategy is proposed to reduce the cost of the multicomponent diffusion model by accurately accounting for the species whose diffusivity is important to the global responses of the combustion systems, and approximating those of less importance by the mixture-averaged model. The reduced model is validated in an n-heptane mechanism with 88 species. In Chapter 8, the influence of Soret

  15. Combustion of spent shales from the Rotem deposit. Pt. 1. Concurrent thermal processes: Pyrolysis and gasification

    Energy Technology Data Exchange (ETDEWEB)

    Zabicky, J. (Ben-Gurion Univ. of the Negev, Beersheba (Israel). Institutes for Applied Research Ben-Gurion Univ. of the Negev, Beersheba (Israel). M.R. Bloch Center for Coal Research); Wohlfarth, A. (Pama - Energy Resources Development Ltd., Arava (Israel))

    1991-06-01

    Spent shales prepared by the Fisher method from oil shales of the Rotem deposit/Israel were studied in a continuous fluidized bed reactor at 700-900deg C under atmospheric pressure, using mixtures of nitrogen and carbon dioxide as the fluidizing gas. A set of simultaneus processes takes place, including pyrolysis of the organic residue in the spent shales, decomposition of calcium carbonate, dehydration of clay phases, decomposition of pyrites, reduction of anhydrite to calcium sulfide and other minor reactions. An important secondary process is gasification of the organic residue by carbon dioxide produced by carbonate decomposition or combustion. The extent to which these reactions take place depends on temperature, composition of the fluidizing gas, particle size of the spent shales, and mean residence time of the particles in the reactor. (orig.).

  16. A numerical study on combustion process in a small compression ignition engine run dual-fuel mode (diesel-biogas)

    Science.gov (United States)

    Ambarita, H.; Widodo, T. I.; Nasution, D. M.

    2017-01-01

    In order to reduce the consumption of fossil fuel of a compression ignition (CI) engines which is usually used in transportation and heavy machineries, it can be operated in dual-fuel mode (diesel-biogas). However, the literature reviews show that the thermal efficiency is lower due to incomplete combustion process. In order to increase the efficiency, the combustion process in the combustion chamber need to be explored. Here, a commercial CFD code is used to explore the combustion process of a small CI engine run on dual fuel mode (diesel-biogas). The turbulent governing equations are solved based on finite volume method. A simulation of compression and expansions strokes at an engine speed and load of 1000 rpm and 2500W, respectively has been carried out. The pressure and temperature distributions and streamlines are plotted. The simulation results show that at engine power of 732.27 Watt the thermal efficiency is 9.05%. The experiment and simulation results show a good agreement. The method developed in this study can be used to investigate the combustion process of CI engine run on dual-fuel mode.

  17. Process performance of the pilot-scale in situ vitrification of a simulated waste disposal site at the Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Carter, J.G.; Koegler, S.S.; Bates, S.O.

    1988-06-01

    Process feasibility studies have been successfully performed on three developmental scales to determine the potential for applying in situ vitrification to intermediate-level (low-level) waste placed in seepage pits and trenches at Oak Ridge National Laboratory (ORNL). In the laboratory, testing was performed in crucibles containing a mixture of 50% ORNL soil and 50% limestone. In an engineering-scale test at Pacific Northwest Laboratory a /1/12/-scale simulation of an ORNL waste trench was constructed and vitrified, resulting in a waste product containing soil and limestone concentrations of 68 wt % and 32 wt %, respectively. In the pilot-scale test a /3/8/-scale simulation of the same trench was constructed and vitrified at ORNL, resulting in soil and limestone concentrations of 80% and 20%, respectively, in the waste product. Results of the three scales of testing indicate that the ORNL intermediate-level (low-level) waste sites can be successfully processed by in situ vitrification; the waste form will retain significant quantities of the cesium and strontium. Because cesium-137 and strontium-90 are the major components of the radionuclide inventory in the ORNL seepage pits and trenches, final field process decontamination factors (i.e., losses to the off-gas system relative to the waste inventory) of 1.0 E + 4 are desired to minimize activity buildup in the off-gas system. 17 refs., 34 figs., 13 tabs.

  18. An in-situ Observation on Initial Aggregation Process of Colloidal Particles near Three-Phase Contact Line of Air, Water and Vertical Substrate

    Institute of Scientific and Technical Information of China (English)

    YAO Can; WANG Yu-Ren; LAN Ding; DUAN Li; KANG Qi

    2008-01-01

    The self-assembling process near the three-phase contact line of air, water and vertical substrate is widely used to produce various kinds of nanostructured materials and devices. We perform an in-situ observation on the selfassembling process in the vicinity of the three phase contact line. Three kinds of aggregations, i.e. particle-particle aggregation, particle-chain aggregation and chain-chain aggregation, in the initial stage of vertical deposition process are revealed by our experiments. It is found that the particle-particle aggregation and the particle-chain aggregation can be qualitatively explained by the theory of the capillary immersion force and mirror image force,while the chain-chain aggregation leaves an opening question for the further studies. The present study may provide more deep insight into the self-assembling process of colloidal particles.

  19. Theoretical studies of nonadiabatic and spin-forbidden processes: Investigations of the reactions and spectroscopy of radical species relevant to combustion reactions and diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Yarkony, D.R. [Johns Hopkins Univ., Baltimore, MD (United States)

    1993-12-01

    This research program focusses on studies of spin-forbidden and electronically nonadiabatic processes involving radical species relevant to combustion reactions and combustion diagnostics. To study the electronic structure aspects of these processes a unique and powerful system of electronic structure programs, developed over the past nine years, the BROOKLYN codes, is employed. These programs enable the authors to address questions basic to the understanding of elementary combustion processes not tractable using more standard quantum chemistry codes.

  20. Effects of Fuel Temperature on Injection Process and Combustion of Dimethyl Ether Engine.

    Science.gov (United States)

    Guangxin, Gao; Zhulin, Yuan; Apeng, Zhou; Shenghua, Liu; Yanju, Wei

    2013-12-01

    To investigate the effects of fuel temperature on the injection process in the fuel-injection pipe and the combustion characteristics of compression ignition (CI) engine, tests on a four stroke, direct injection dimethyl ether (DME) engine were conducted. Experimental results show that as the fuel temperature increases from 20 to 40 °C, the sound speed is decreased by 12.2%, the peak line pressure at pump and nozzle sides are decreased by 7.2% and 5.6%, respectively. Meanwhile, the injection timing is retarded by 2.2 °CA and the injection duration is extended by 0.8 °CA. Accordingly, the ignition delay and the combustion duration are extended by 0.7 °CA and 4.0 °CA, respectively. The cylinder peak pressure is decreased by 5.4%. As a result, the effective thermal efficiency is decreased, especially for temperature above 40 °C. Before beginning an experiment, the fuel properties of DME, including the density, the bulk modulus, and the sound speed were calculated by "ThermoData." The calculated result of sound speed is consistent with the experimental results.

  1. Study on the Combustion Process and Emissions of a Turbocharged Diesel Engine with EGR

    Directory of Open Access Journals (Sweden)

    Mei Deqing

    2012-01-01

    Full Text Available A high pressure EGR system was adopted to a turbocharged inter-cooled diesel engine, to analyze its combustion and emission characteristics under the condition of different loads and constant speed. Under the same steady operating mode, with the increase of EGR rate, the temperature of compressed gas ascended, the ignition delay was shortened, the pressure and temperature of the burned gas descended, and the combustion process was prolonged. According to the experimental data, it was found that, at the same EGR rate, lower the load of engine was, lower the temperature in cylinder, and higher the increase rate of CO was. However, the increase rate of HC present a falling trend. The decrease rate of the specific emission of NOx linearly varied with EGR rate with a slope of 1.651. The increase rate of smoke opacity behaved a second-order polynomial uprising trend, and the higher the load was, the sharpener the smoke opacity deteriorated, with the increase of EGR rate. From the point of emission view, the engine with EGR system can achieve the lesser exhaust emissions in some operations by adjusting the engine parameters.

  2. Effect of grinding process on the level of leachability of the contaminants from the fly ashes from combustion of biomass

    Directory of Open Access Journals (Sweden)

    Pawluk Aleksandra

    2016-01-01

    Full Text Available The most commonly used renewable energy source in Polish energy production companies is solid biomass which is used both as a separate fuel or as a component co-incinerated together with (mostly hard coal. During its incineration the biomass generates by-products with diverse and variable physicochemical properties. The most of the waste from production of electricity and/or heat are fly ashes. The fly ashes from combustion of biomass are a particular kind of waste distinguished by high level of leaching of contaminants and variable chemical composition. The by-products from combustion can only be used in production when their physicochemical properties meet specific parameters. This article presents results of research on leachability of chemical pollutants from dry ashes of combustion or co-combustion of biomass. The study of the impact of grinding of ashes on the level of their leachability was also conducted. Ashes from combustion of biomass as well as their mixture with fluidized ash from combustion of charcoal were submitted to grinding process. Afterwards level of leachability was measured on them to determine prospect of utility in mining technologies.

  3. Models of Non-Stationary Thermodynamic Processes in Rocket Engines Taking into Account a Chemical Equilibrium of Combustion Products

    Directory of Open Access Journals (Sweden)

    A. V. Aliev

    2015-01-01

    Full Text Available The paper considers the two approach-based techniques for calculating the non-stationary intra-chamber processes in solid-propellant rocket engine (SPRE. The first approach assumes that the combustion products are a mechanical mix while the other one supposes it to be the mix, which is in chemical equilibrium. To enhance reliability of solution of the intra ballistic tasks, which assume a chemical equilibrium of combustion products, the computing algorithms to calculate a structure of the combustion products are changed. The algorithm for solving a system of the nonlinear equations of chemical equilibrium, when determining the iterative amendments, uses the orthogonal QR method instead of a method of Gauss. Besides, a possibility to apply genetic algorithms in a task about a structure of combustion products is considered.It is shown that in the tasks concerning the prediction of non-stationary intra ballistic characteristics in a solid propellant rocket engine, application of models of mechanical mix and chemically equilibrium structure of combustion products leads to qualitatively and quantitatively coinciding results. The maximum difference in parameters is 5-10%, at most. In tasks concerning the starting operation of a solid sustainer engine with high-temperature products of combustion difference in results is more essential, and can reach 20% and more.A technique to calculate the intra ballistic parameters, in which flotation of combustion products is considered in the light of a spatial statement, requires using the high-performance computer facilities. For these tasks it is offered to define structure of products of combustion and its thermo-physical characteristics, using the polynoms coefficients of which should be predefined.

  4. Synthesis of nano-particle and highly porous conducting perovskites from simple in situ sol–gel derived carbon templating process

    Indian Academy of Sciences (India)

    Wei Zhou; Ran Ran; Zongping Shao; Wanqin Jin; Nanping Xu

    2010-08-01

    Nano-sized La0.6Sr0.4Co0.2Fe0.8O$_{3–\\delta}$ (LSCF) and La0.8Sr0.2MnO$_{3–\\delta}$ (LSM) oxides were synthesized by a simple in situ sol–gel derived carbon templating process. Nano-sized LSCF–carbon and LSM–carbon composites were first obtained with a grain size of 20–30 nm. Further calcination of the obtained composites under air resulted in the nano-sized pure-phase perovskites with crystalline size of as small as 14 nm. Such a decrease in crystalline size of perovskite via the indirect calcination process was ascribed to the suppressing effect of carbon in the grain growth of perovskite. Furthermore, when the in situ created carbon was applied as a template for pore forming, a highly porous perovskite sintering body packing from the nano-sized perovskite oxide was obtained.

  5. Numerical Simulation and Optimization of Enhanced Oil Recovery by the In Situ Generated CO2 Huff-n-Puff Process with Compound Surfactant

    Directory of Open Access Journals (Sweden)

    Yong Tang

    2016-01-01

    Full Text Available This paper presents the numerical investigation and optimization of the operating parameters of the in situ generated CO2 Huff-n-Puff method with compound surfactant on the performance of enhanced oil recovery. First, we conducted experiments of in situ generated CO2 and surfactant flooding. Next, we constructed a single-well radial 3D numerical model using a thermal recovery chemical flooding simulator to simulate the process of CO2 Huff-n-Puff. The activation energy and reaction enthalpy were calculated based on the reaction kinetics and thermodynamic models. The interpolation parameters were determined through history matching a series of surfactant core flooding results with the simulation model. The effect of compound surfactant on the Huff-n-Puff CO2 process was demonstrated via a series of sensitivity studies to quantify the effects of a number of operation parameters including the injection volume and mole concentration of the reagent, the injection rate, the well shut-in time, and the oil withdrawal rate. Based on the daily production rate during the period of Huff-n-Puff, a desirable agreement was shown between the field applications and simulated results.

  6. An in situ powder neutron diffraction study of nano-precipitate formation during processing of oxide-dispersion-strengthened ferritic steels

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hongtao, E-mail: hongtao.zhang@materials.ox.ac.uk [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Gorley, Michael J. [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Chong, Kok Boon; Fitzpatrick, Michael E. [Materials Engineering, The Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom); Roberts, Steve G.; Grant, Patrick S. [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom)

    2014-01-05

    Highlights: • In situ powder neutron diffraction to study precipitate formation in ODS steel. • First real time observation of nano-precipitate formation during processing. • Y{sub 2}O{sub 3} particles were fully dissolved into steel matrix during mechanical alloy. • The precipitation occurred during annealing of as-milled powder above 900 °C. -- Abstract: The evolution of phases in a Fe–14Cr–10Y{sub 2}O{sub 3} (wt%) oxide-dispersion-strengthened ferritic steel during mechanical alloying (MA) and subsequent annealing was studied by high resolution powder neutron diffraction, with emphasis on the kinetics of oxide-based nano-precipitate formation. Y{sub 2}O{sub 3} particles were completely dissolved into the ferritic matrix during MA. The formation of nano-precipitates was then observed by in situ thermo-diffraction experiments during annealing of as-milled powder above 900 °C, supported by scanning electron microscopy. This revealed nano-precipitate coarsening with increasing annealing temperature. Powder microhardness was measured at various processing stages, and hardness changes are discussed in terms of the measured phase fractions, crystallite size and lattice strain at different temperatures and times.

  7. THE PERCEPTUAL COGNITIVE PROCESSES UNDERPINNING SKILLED PERFORMANCE IN VOLLEYBALL: EVIDENCE FROM EYE-MOVEMENTS AND VERBAL REPORTS OF THINKING INVOLVING AN IN SITU REPRESENTATIVE TASK

    Directory of Open Access Journals (Sweden)

    José Afonso

    2012-06-01

    Full Text Available An extensive body of work has focused on the processes underpinning perceptual-cognitive expertise. The majority of researchers have used film-based simulations to capture superior performance. We combined eye movement recording and verbal reports of thinking to explore the processes underpinning skilled performance in a complex, dynamic, and externally paced representative volleyball task involving in situ data collection. Altogether, 27 female volleyball players performed as centre backcourt defenders in simulated sessions while wearing an eye-tracking device. After each sequence, athletes were questioned concerning their perception of the situation. The visual search strategies employed by the highly-skilled players were more exploratory than those used by skilled players, involving more fixations to a greater number of locations. Highly-skilled participants spent more time fixating on functional spaces between two or more display areas, while the skilled participants fixated on the ball trajectory and specific players. Moreover, highly-skilled players generated more condition concepts with higher levels of sophistication than their skilled counterparts. Findings highlight the value of using representative task designs to capture performance in situ

  8. In-situ polymerized cellulose nanocrystals (CNC)-poly(l-lactide) (PLLA) nanomaterials and applications in nanocomposite processing.

    Science.gov (United States)

    Miao, Chuanwei; Hamad, Wadood Y

    2016-11-20

    CNC-PLLA nanomaterials were synthesized via in-situ ring-opening polymerization of l-lactide in the presence of CNC, resulting in hydrophobic, homogeneous mixture of PLLA-grafted-CNC and free PLLA homopolymer. The free PLLA serves two useful functions: as barrier to further prevent PLLA-g-CNC from forming aggregates, and in creating improved interfacial properties when these nanomaterials are blended with other polymers, hence enhancing their performance. CNC-PLLA nanomaterials can be used for medical or engineering applications as-they-are or by compounding with suitable biopolymers using versatile techniques, such as solution casting, co-extrusion or injection molding, to form hybrid nanocomposites of tunable mechanical properties. When compounded with commercial-grade PLA, the resulting CNC-PLA nanocomposites appear transparent and have tailored (dynamic and static) mechanical and barrier properties, approaching those of poly(ethylene terephthalate), PET. The effect of reaction conditions on the properties of CNC-PLLA nanomaterials have been carefully studied and detailed throughout the paper.

  9. The Microstructure Analysis of Barium M- Hexaferrite Particles Coated by Pani Conducting Material with In Situ Polymerization Process

    Science.gov (United States)

    Zainuri, M.; Amalia, L.

    2017-05-01

    Barium M-Hexaferrite (BaM) was synthesized by coprecipitation method and doped with Zn. Polyaniline (PANI) was synthesized by chemically and doped DBSA. The composite of PANI/BaM was synthesized by in situ polymerization method. The phase identification of the sample was performed by XRD, FTIR and SEM. Based on XRD data, the phase composition of BaM and hematite are 85.52 % and 14.48%. The characteristic peaks of PANI occur at 3435, 1637, 1473, 1298, 1127, 1009, and 799 cm-1. The characteristic metal oxide stretching peaks of BaM occurs at 575 and 437 cm-1. There is no phase changing in PANI/BaM composite. Based on SEM photography, the shape of BaM is hexagonal. The particle size of BaM powder ranges from 400-700 nm. The qualitative interfacial bonding between PANI and BaM particles are conducted very well and the both materials have good wettability.

  10. Physicochemical Process, Crustacean, and Microcystis Biomass Changes In Situ Enclosure after Introduction of Silver Carp at Meiliang Bay, Lake Taihu

    Directory of Open Access Journals (Sweden)

    Chengjie Yin

    2017-01-01

    Full Text Available In order to control cyanobacteria blooms with silver carp in Lake Taihu, an in situ experiment was carried out by stocking silver carp at a biomass of 35, 70, and 150 g m-3 and no carp control in waterproof enclosures. Physicochemical water parameters and biomass of plankton were measured in enclosures to evaluate the suitable stocking density of silver carp for relieving internal nutrients and constraining cyanobacteria growth in Lake Taihu. It is found that the 35 g m-3 silver carp group and 70 g m-3 silver carp group presented lower total phosphorus, lower chlorophyll-a, and higher water transparency. Increased nitrogen to phosphorus ratio, which indicated the result of algae decline in fish presence enclosures, was attributed to decline of phosphorus. Phosphorus decline also exerted limitation on reestablish of cyanobacteria bloom. Crustacean zooplankton biomass and Microcystis biomass decreased significantly in fish presence enclosures. Silver carp could be more effective to regulate algae bloom in enclosures with dense cyanobacteria. Therefore, nonclassic manipulation is supposed to be appropriate method to get rid of cyanobacteria blooms in Lake Taihu by stocking 35 to 70 g m-3 silver carp in application.

  11. A new system for sodium flux growth of bulk GaN. Part II: in situ investigation of growth processes

    KAUST Repository

    Von Dollen, Paul

    2016-09-09

    We report recent results of bulk GaN crystal growth using the sodium flux method in a new crucible-free growth system. We observed a (0001) Ga face (+c-plane) growth rate >50 µm/h for growth at a N2 overpressure of ~5 MPa and 860 °C, which is the highest crystal growth rate reported for this technique to date. Omega X-ray rocking curve (ω-XRC) measurements indicated the presence of multiple grains, though full width at half maximum (FWHM) values for individual peaks were <100 arcseconds. Oxygen impurity concentrations as measured by secondary ion mass spectroscopy (SIMS) were >1020 atoms/cm3. By monitoring the nitrogen pressure decay over the course of the crystal growth, we developed an in situ method that correlates gas phase changes with precipitation of GaN from the sodium-gallium melt. Based on this analysis, the growth rate may have actually been as high as 90 µm/h, as it would suggest GaN growth ceased prior to the end of the run. We also observed gas phase behavior identified as likely characteristic of GaN polynucleation.

  12. A new system for sodium flux growth of bulk GaN. Part II: in situ investigation of growth processes

    Science.gov (United States)

    Von Dollen, Paul; Pimputkar, Siddha; Alreesh, Mohammed Abo; Nakamura, Shuji; Speck, James S.

    2016-12-01

    We report recent results of bulk GaN crystal growth using the sodium flux method in a new crucible-free growth system. We observed a (0001) Ga face (+c-plane) growth rate >50 μm/h for growth at a N2 overpressure of 5 MPa and 860 °C, which is the highest crystal growth rate reported for this technique to date. Omega X-ray rocking curve (ω-XRC) measurements indicated the presence of multiple grains, though full width at half maximum (FWHM) values for individual peaks were 100 arcseconds. Oxygen impurity concentrations as measured by secondary ion mass spectroscopy (SIMS) were >1020 atoms/cm3. By monitoring the nitrogen pressure decay over the course of the crystal growth, we developed an in situ method that correlates gas phase changes with precipitation of GaN from the sodium-gallium melt. Based on this analysis, the growth rate may have actually been as high as 90 μm/h, as it would suggest GaN growth ceased prior to the end of the run. We also observed gas phase behavior identified as likely characteristic of GaN polynucleation.

  13. The new energy processes and the new approaches of the combustion. The environmental impact decrease; Nouveaux procedes energetiques et nouvelles approches de la combustion. Reduction de l'impact environnemental

    Energy Technology Data Exchange (ETDEWEB)

    Cabot, G. [CORIA, 76 - Mont Saint Aignan (France); Caillat, S. [Ecole des Mines de Douai, Dept. Energetique, 59 (France); Guillet, R. [Gaz de France, GDF DR, 93 - La Plaine Saint-Denis (France)] [and others

    2001-07-01

    During this day organized by the french society of the science of heat (SFT), seven papers have been presented. They deal with new processes of combustion leading to a better air quality for the environment. The first process concerns the wet combustion, an energy efficient and environmentally friendly technique, its properties and the DHC (hygrometric diagram of combustion) analysis. The flames mechanisms and the swirl process are presented in a second part with the analysis of the radiant heat transfers and the nitrogen oxides emissions. (A.L.B.)

  14. Pressure oscillations and instability of working processes in the combustion chambers of solid rocket motors

    Science.gov (United States)

    Emelyanov, V. N.; Teterina, I. V.; Volkov, K. N.; Garkushev, A. U.

    2017-06-01

    Metal particles are widely used in space engineering to increase specific impulse and to supress acoustic instability of intra-champber processes. A numerical analysis of the internal injection-driven turbulent gas-particle flows is performed to improve the current understanding and modeling capabilities of the complex flow characteristics in the combustion chambers of solid rocket motors (SRMs) in presence of forced pressure oscillations. The two-phase flow is simulated with a combined Eulerian-Lagrangian approach. The Reynolds-averaged Navier-Stokes equations and transport equations of k - ε model are solved numerically for the gas. The particulate phase is simulated through a Lagrangian deterministic and stochastic tracking models to provide particle trajectories and particle concentration. The results obtained highlight the crucial significance of the particle dispersion in turbulent flowfield and high potential of statistical methods. Strong coupling between acoustic oscillations, vortical motion, turbulent fluctuations and particle dynamics is observed.

  15. Oxidative potential of gas phase combustion emissions - An underestimated and potentially harmful component of air pollution from combustion processes

    Science.gov (United States)

    Stevanovic, S.; Vaughan, A.; Hedayat, F.; Salimi, F.; Rahman, M. M.; Zare, A.; Brown, R. A.; Brown, R. J.; Wang, H.; Zhang, Z.; Wang, X.; Bottle, S. E.; Yang, I. A.; Ristovski, Z. D.

    2017-06-01

    The oxidative potential (OP) of the gas phase is an important and neglected aspect of environmental toxicity. Whilst prolonged exposure to particulate matter (PM) associated reactive oxygen species (ROS) have been shown to lead to negative health effects, the potential for compounds in gas phase to cause similar effects is yet to be understood. In this study we describe: the significance of the gas phase OP generated through vehicle emissions; discuss the origin and evolution of species contributing to measured OP; and report on the impact of gas phase OP on human lung cells. The model aerosol for this study was exhaust emitted from a Euro III Common-rail diesel engine fuelled with different blends of diesel and biodiesel. The gas phase of these emissions was found to be potentially as hazardous as the particle phase. Fuel oxygen content was found to negatively correlate with the gas phase OP, and positively correlate with particle phase OP. This signifies a complex interaction between reactive species present in gas and particle phase. Furthermore, this interaction has an overarching effect on the OP of both particle and gas phase, and therefore the toxicity of combustion emissions.

  16. Study on drying and combustion process in grate-CFB incinerator

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The drying and combustion process in the combined grate and circulating fluidized bed(grate-CFB) municipal solid waste(MSW) incinerator was investigated experimentally and mathematically.The drying grate bed was simulated by a muffle furnace,which could be controlled at a constant tempera-ture level.The kind of wastes,thickness of waste layer fed and temperature were chosen as the ad-justable parameters to study their effect on the drying process.The experimental results indicated that the hydrophilic wastes were more difficult to be dried than the hydrophobic wastes.The higher the temperature is the easier the waste is to be dried.The thinner waste layer is favorable to drying the waste.The pyrolysis experiment in the furnace showed that the higher temperature level could reduce the conversion rate of carbon to carbon monoxide.The semi-empirical mathematical model that in-cluded the bed material distribution submodel,volatile matter release submodel,carbon particle combustion submodel and so on was proposed.A 260 t/d grate-CFB incinerator was modeled and the model predicted bulk density agreed with the measured value from industrial field test.The predicted flue gas(e.g.CO2,CO) concentration deviated slightly from the industrial test data.The parameters and variables used in the model were determined by the experiments or practical field test.This model can be used to design the grate-CFB incinerator and guide its operation.

  17. Thermal Behavior and Kinetics of Raw/Pyrolytic Wood and Coal Blends during Co-combustion Process

    Institute of Scientific and Technical Information of China (English)

    Jian DING; Qing-cai LIU; Li-jun JIANG; Guo-qing LIU; Shan REN; Jian YANG; Lu YAO; Fei MENG

    2016-01-01

    The thermal properties of raw wood (RW)biomass,corresponding pyrolytic wood (PW)biomass,and their blends with anthracite coal (AC)were evaluated under combustion conditions with a thermogravimetric analysis (TGA)method.The blending ratios of the biomass with AC ranging from 0 to 100 mass% were taken into consider-ation to investigate the thermal behavior and kinetics of these blends during their co-combustion.For blends with dif-ferent ratios of the RW to AC and 100% AC (100 AC),two distinct mass loss peaks related to the release or com-bustion process of the volatiles and the combustion of the char were noted.The addition of a higher ratio of RW or PW into AC can improve the combustion process of the blends.The thermal behavior of the RW/AC or PW/AC blends could not be characterized by a simple linear correlation of their pure material thermal behavior.With the RW/PW addition ratios varying from 25 mass% to 80 mass%,the apparent activation energy of the blends gradually decreased from 48.46 to 34.93 kJ/mol and from 82.74 to 37.81 kJ/mol for the RW/AC and PW/AC blends,re-spectively,with high correlation coefficient (R2 )values ranging from 0.995 6 to 0.998 4.

  18. The Tensions of In Situ Visualization.

    Science.gov (United States)

    Moreland, Kenneth

    2016-01-01

    In situ visualization is the coupling of visualization software with a simulation or other data producer to process the data "in memory" before the data are offloaded to a storage system. Although in situ visualization provides superior analysis, it has implementation tradeoffs resulting from conflicts with some traditional expected requirements. Numerous conflicting requirements create tensions that lead to difficult implementation tradeoffs. This article takes a look at the most prevailing tensions of in situ visualization.

  19. Development of carbon nanotubes based gas diffusion layers by in situ chemical vapor deposition process for proton exchange membrane fuel cells

    Science.gov (United States)

    Kannan, A. M.; Kanagala, P.; Veedu, V.

    A proprietary in situ chemical vapor deposition (CVD) process was developed for gas diffusion layer (GDL) by growing a micro-porous layer on the macro-porous, non-woven fibrous carbon paper. The characteristics of the GDL samples such as, surface morphology, wetting characteristics, and cross-section were characterized using electron microscopes, goniometer and focused ion beam, respectively. Fuel cell performance of the GDLs was evaluated using single cell with hydrogen/oxygen as well as hydrogen/air at ambient pressure, at elevated temperature and various RH conditions using Nafion-212 as an electrolyte. The GDLs with in situ growth of micro-porous layers containing carbon nanotubes (CNTs) without any hydrophobic agent showed significant improvement in mechanical robustness as well as fuel cell performance at elevated temperature at lower RH conditions. The micro-porous layer of the GDLs as seen under scanning electron microscope showed excellent surface morphology with surface homogeneity through reinforcement by the multi-walled CNTs.

  20. An 18. century ingredient in a 21. century solution : a steam-based process is helping overcome the challenges of in situ oil sands recovery

    Energy Technology Data Exchange (ETDEWEB)

    Sundararajan, B.

    2009-03-15

    Recent technological innovations, more efficient methods such as steam-assisted gravity drainage (SAGD), as well as the favorability of oil prices have led to renewed interest in extracting oil from in situ deposits. This article provided background information on the origins of SAGD and discussed technical consultation services that are offered by Canadian-based Norwest Corporation. Norwest provides comprehensive services aimed at optimizing every stage of project development in four principal areas, notably geology, engineering, water resources, and environmental and management consulting. Key challenges in the SAGD process were also outlined with particular reference to the situation of vertical and horizontal bores; insensitivity to thin shale streaks and other vertical barriers to steam and fluid flow; and cost of steam generation. It was concluded that both mining and in-situ oil sands developers are committed to minimizing the impact they have on the land by avoiding sensitive habitats, optimizing land use and working with other users to reduce the overall footprint of industry. 2 figs.

  1. Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbon Fuels. Thermochemical Research Pathways with In Situ and Ex Situ Upgrading of Fast Pyrolysis Vapors

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, A.; Sahir, A.; Tan, E.; Humbird, D.; Snowden-Swan, L. J.; Meyer, P.; Ross, J.; Sexton, D.; Yap, R.; Lukas, J.

    2015-03-01

    This report was developed as part of the U.S. Department of Energy’s Bioenergy Technologies Office’s efforts to enable the development of technologies for the production of infrastructurecompatible, cost-competitive liquid hydrocarbon fuels from biomass. Specifically, this report details two conceptual designs based on projected product yields and quality improvements via catalyst development and process integration. It is expected that these research improvements will be made within the 2022 timeframe. The two conversion pathways detailed are (1) in situ and (2) ex situ upgrading of vapors produced from the fast pyrolysis of biomass. While the base case conceptual designs and underlying assumptions outline performance metrics for feasibility, it should be noted that these are only two of many other possibilities in this area of research. Other promising process design options emerging from the research will be considered for future techno-economic analysis.

  2. Research on the Combustion Characteristics of a Free-Piston Gasoline Engine Linear Generator during the Stable Generating Process

    Directory of Open Access Journals (Sweden)

    Yuxi Miao

    2016-08-01

    Full Text Available The free-piston gasoline engine linear generator (FPGLG is a new kind of power plant consisting of free-piston gasoline engines and a linear generator. Due to the elimination of the crankshaft mechanism, the piston motion process and the combustion heat release process affect each other significantly. In this paper, the combustion characteristics during the stable generating process of a FPGLG were presented using a numerical iteration method, which coupled a zero-dimensional piston dynamic model and a three-dimensional scavenging model with the combustion process simulation. The results indicated that, compared to the conventional engine (CE, the heat release process of the FPGLG lasted longer with a lower peak heat release rate. The indicated thermal efficiency of the engine was lower because less heat was released around the piston top dead centre (TDC. Very minimal difference was observed on the ignition delay duration between the FPGLG and the CE, while the post-combustion period of the FPGLG was significantly longer than that of the CE. Meanwhile, the FPGLG was found to operate more moderately due to lower peak in-cylinder gas pressure and a lower pressure rising rate. The potential advantage of the FPGLG in lower NOx emission was also proven with the simulation results presented in this paper.

  3. Four Models of In Situ Simulation

    DEFF Research Database (Denmark)

    Musaeus, Peter; Krogh, Kristian; Paltved, Charlotte

    2014-01-01

    that there are four fruitful approaches to in situ simulation: (1) In situ simulation informed by reported critical incidents and adverse events from emergency departments (ED) in which team training is about to be conducted to write scenarios. (2) In situ simulation through ethnographic studies at the ED. (3) Using...... prewritten scenarios from the simulation lab and transferring them to in situ simulation. (4) Action research – insider or participant action research to obtain in-depth understanding of team processes to guide scenario design. We evaluate the approach relying on Marks’ et al. taxonomy that posits...... the following processes: Transition processes, Action processes and Interpersonal processes. Design and purpose This abstract suggests four approaches to in situ simulation. A pilot study will evaluate the different approaches in two emergency departments in the Central Region of Denmark. Methods The typology...

  4. Pre-Combustion Carbon Capture by a Nanoporous, Superhydrophobic Membrane Contactor Process

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Howard; Zhou, S James; Ding, Yong; Bikson, Ben

    2012-03-31

    This report summarizes progress made during Phase I and Phase II of the project: "Pre-Combustion Carbon Capture by a Nanoporous, Superhydrophobic Membrane Contactor Process," under contract DE-FE-0000646. The objective of this project is to develop a practical and cost effective technology for CO{sub 2} separation and capture for pre-combustion coal-based gasification plants using a membrane contactor/solvent absorption process. The goals of this technology development project are to separate and capture at least 90% of the CO{sub 2} from Integrated Gasification Combined Cycle (IGCC) power plants with less than 10% increase in the cost of energy services. Unlike conventional gas separation membranes, the membrane contactor is a novel gas separation process based on the gas/liquid membrane concept. The membrane contactor is an advanced mass transfer device that operates with liquid on one side of the membrane and gas on the other. The membrane contactor can operate with pressures that are almost the same on both sides of the membrane, whereas the gas separation membranes use the differential pressure across the membrane as driving force for separation. The driving force for separation for the membrane contactor process is the chemical potential difference of CO{sub 2} in the gas phase and in the absorption liquid. This process is thus easily tailored to suit the needs for pre-combustion separation and capture of CO{sub 2}. Gas Technology Institute (GTI) and PoroGen Corporation (PGC) have developed a novel hollow fiber membrane technology that is based on chemically and thermally resistant commercial engineered polymer poly(ether ether ketone) or PEEK. The PEEK membrane material used in the membrane contactor during this technology development program is a high temperature engineered plastic that is virtually non-destructible under the operating conditions encountered in typical gas absorption applications. It can withstand contact with most of the common treating

  5. Numerical simulations of industrial processes involving fluid dynamics, combustion and radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ducrocq, J. [Air Liquide, Centre de Recherche Claude-Delorme, Jouy-en-Josas (France)

    1997-12-31

    Moving out of the scientific community research laboratories, computational fluid dynamics (CFD) software packages are now allowing industrials to analyse and optimize industrial processes involving the use of gases, liquids and even some two-phase fluids. Their attractiveness and their impact stems out from the opportunity they offer to bring insight into an existing unit, or even at the design stage, by displaying the spatial distribution of process relevant variables such as temperature, concentration. The filling of the spacing in between a two-layer window is a simple example. This new opportunity of visualisation is at times an unique way, when the process environment is an opaque one, such as liquid metal flowing into a tundish or when measurements of flows may be a long and tedious work, such as flows within water treatment basins. This environment we are to investigate in order to optimize can also be a harsh one, due to its high temperature level for example. Such are burners. But then pure fluid flow analysis, such as cold flow water models, has too many shortcomings. The description of combustion processes and of radiation become a necessary feature in order to describe thermal heat transfer or to locate `hot spots`. Such numerical models showing our oxycombustion expertise in glass melting will be presented. (author)

  6. Processing and Characterization of In-Situ Generated Nanosilver and Er3+ Co-Doped Bromoborosilicate Glass Nanocomposites.

    Science.gov (United States)

    Sarkar, Jit; Tarafder, Anal; Karmakar, Basudeb

    2015-09-01

    In the present investigation, bromoborosilicate glass of composition 6Na2O-19K2O-10BaBr2- 2Al2O3-15B2O3-48SiO2 (mole %) added with 0.2 wt% SnO, co-doped with 0.001 wt% Ag and 0.7 wt% Er2O3 in excess amount, was prepared by melt-quench technique. The metal-glass nanocomposites were derived involving a single-step in-situ thermochemical reduction of the precursor glass subjecting an isothermal heat-treatment protocol. The precursor glass and metal glass nanocomposites were characterized by dilatometer, differential scanning calorimeter, X-ray diffractometer, field emission scanning electron microscope, transmission electron microscope, Fourier transform infrared spectrometer, UV-Vis-NIR spectrophotometer, fluorimeter etc. XRD spectra represent the amorphous nature of the samples and without having any sharp peaks of silver (Ag0) and barium bromide (BaBr2). But the FESEM micrograph shows the presence of BaBr2 crystallites in clusters and the TEM micrograph shows the presence of AgO nanoparticles of different shapes and sizes. The precursor glass sample shows sharp absorption peak at 378 nm and 521 nm due to the 4G11,2 and 2H11/2 energy levels of Er3+ but glass nanocomposites exhibit another band at 410 nm due to the surface plasmon resonance of Ag0 nanoparticles. They also show sharp emis- sion peak at 1542 nm due to 4115/2 -+4l13/2 transition of Er3+ ions and prominent upconverted peaks at 630 nm (red, medium) and 645 nm (red, strong) due to 4F9/2 + 1 15/2 transition. The intensity of the absorption and upconverted peaks increases with the duration of heat treatment, having maximum intensity at 5 h and the intensity of the emission peak increases with heat treatment upto 1 h and then decreases for 5 h. Thus these metal-glass nanocomposites show enhanced photoluminescence upconversion and are promising material for different photonic applications.

  7. Fuel decomposition and boundary-layer combustion processes of hybrid rocket motors

    Science.gov (United States)

    Chiaverini, Martin J.; Harting, George C.; Lu, Yeu-Cherng; Kuo, Kenneth K.; Serin, Nadir; Johnson, David K.

    1995-01-01

    Using a high-pressure, two-dimensional hybrid motor, an experimental investigation was conducted on fundamental processes involved in hybrid rocket combustion. HTPB (Hydroxyl-terminated Polybutadiene) fuel cross-linked with diisocyanate was burned with GOX under various operating conditions. Large-amplitude pressure oscillations were encountered in earlier test runs. After identifying the source of instability and decoupling the GOX feed-line system and combustion chamber, the pressure oscillations were drastically reduced from +/-20% of the localized mean pressure to an acceptable range of +/-1.5% Embedded fine-wire thermocouples indicated that the surface temperature of the burning fuel was around 1000 K depending upon axial locations and operating conditions. Also, except near the leading-edge region, the subsurface thermal wave profiles in the upstream locations are thicker than those in the downstream locations since the solid-fuel regression rate, in general, increases with distance along the fuel slab. The recovered solid fuel slabs in the laminar portion of the boundary layer exhibited smooth surfaces, indicating the existence of a liquid melt layer on the burning fuel surface in the upstream region. After the transition section, which displayed distinct transverse striations, the surface roughness pattern became quite random and very pronounced in the downstream turbulent boundary-layer region. Both real-time X-ray radiography and ultrasonic pulse-echo techniques were used to determine the instantaneous web thickness burned and instantaneous solid-fuel regression rates over certain portions of the fuel slabs. Globally averaged and axially dependent but time-averaged regression rates were also obtained and presented.

  8. Intrinsic and metal-doped gallium oxide based high-temperature oxygen sensors for combustion processes

    Science.gov (United States)

    Rubio, Ernesto Javier

    Currently, there is enormous interest in research, development and optimization of the combustion processes for energy harvesting. Recent statistical and economic analyses estimated that by improving the coal-based firing/combustion processes in the power plants, savings up to $450-500 million yearly can be achieved. Advanced sensors and controls capable of withstanding extreme environments such as high temperatures, highly corrosive atmospheres, and high pressures are critical to such efficiency enhancement and cost savings. For instance, optimization of the combustion processes in power generation systems can be achieved by sensing, monitoring and control of oxygen, which is a measure of the completeness of the process and can lead to enhanced efficiency and reduced greenhouse gas emissions. However, despite the fact that there exists a very high demand for advanced sensors, the existing technologies suffer from poor 'response and recovery times' and 'long-term stability.' Motivated by the aforementioned technological challenges, the present work was focused on high-temperature (≥700 °C) oxygen sensors for application in power generation systems. The objective of the present work is to investigate nanostructured gallium oxide (2O3) based sensors for oxygen sensing, where we propose to conduct in-depth exploration of the role of refractory metal (tungsten, W, in this case) doping into 2O 3 to enhance the sensitivity, selectivity, stability ("3S" criteria) and reliability of such sensors while keeping cost economical. Tungsten (W) doped gallium oxide (2O3) thin films were deposited via rf-magnetron co-sputtering of W-metal and Ga2O3-ceramic targets. Films were produced by varying the sputtering power applied to the W-target in order to achieve variable W content into 2O3 films while substrate temperature was kept constant at 500 °C. Chemical composition, chemical valence states, microstructure and crystal structure of as-grown and post-annealed W-doped 2O3

  9. Predicting Aerosol Based Emissions in a Post Combustion CO2 Capture Process Using an Aspen Plus Model

    NARCIS (Netherlands)

    Khakharia, P.M.; Mertens, J.; Vlugt, T.J.H.; Goetheer, E.

    2014-01-01

    Industrial scale implementation of post combustion CO2 capture (PCCC) can be hindered by solvent emissions due to its impact on the environment and the operating costs. The issue of aerosol based emissions has only been recently reported for a PCCC process and very little fundamental knowledge is

  10. ANALYSIS OF TRACE-LEVEL ORGANIC COMBUSTION PROCESS EMISSIONS USING NOVEL MULTIDIMENSIONAL GAS CHROMATOGRAPHY-MASS SPECTROMETRY PROCEDURES

    Science.gov (United States)

    The paper discusses the analysis of trace-level organic combustion process emissions using novel multidimensional gas chromatography-mass spectrometry (MDGC-MS) procedures. It outlines the application of the technique through the analyses of various incinerator effluent and produ...

  11. Predicting Aerosol Based Emissions in a Post Combustion CO2 Capture Process Using an Aspen Plus Model

    NARCIS (Netherlands)

    Khakharia, P.M.; Mertens, J.; Vlugt, T.J.H.; Goetheer, E.

    2014-01-01

    Industrial scale implementation of post combustion CO2 capture (PCCC) can be hindered by solvent emissions due to its impact on the environment and the operating costs. The issue of aerosol based emissions has only been recently reported for a PCCC process and very little fundamental knowledge is av

  12. 柴油机燃烧过程的数值模拟及燃烧室改进%Numerical simulation for combustion process of diesel engine and improvement of combustion chamber

    Institute of Scientific and Technical Information of China (English)

    潘剑锋; 卢青波; 王谦; 万彦辉; 张梦云

    2012-01-01

    为了改善柴油机燃烧室内混合气的形成状态和燃烧质量,对改装DLH1105型直喷柴油机缸内喷雾和燃烧过程进行了动态数值模拟,并在压缩比不变的情况下设计了3种不同结构的燃烧室,分别为敞口型、直口型和缩口型.通过STAR-CD软件对3种结构的燃烧室进行了三维数值模拟,获得了柴油机的缸内流场、燃油质量分数分布和温度场.结果表明:模拟出的缸内喷雾和燃烧过程与可视化试验的结果吻合,计算模拟的方法可靠;缩口型燃烧室有较强的挤流强度,较长的涡流持续期,使混合气质量和燃烧性能优于直口燃烧室和敞口燃烧室,缸内压力和平均温度最高,Soot生成量最少,同时NO的生成量最大.%In order to improve the mixture formation and combustion quality in combustion chamber of DLH1105 diesel engine, the cylinder spray and combustion process were numerically simulated. Three combustion chambers of open combustion chamber, toroidal combustion chamber and reentrant combustion chamber were designed at constant compression ratio. 3-D numerical simulation of the three type combustion chambers were achieved by STAR-CD software to obtain flow field, distribution of fuel mass fraction and temperature field in the diesel engine cylinder. The simulation result shows that cylinder spray and combustion process are consistent with those of visualized experiment, which means that the method of computational simulation is reliable. Reentrant combustion chamber has strong squish with long swirl period, which results in better mixture gas and combustion performance than those of toroidal combustion chamber and open combustion chamber. The pressure and temperature in reentrant combustion cylinder are high with low shoot formation and high NO amount.

  13. In situ x-ray observations of the diamond formation process in the C-H sub 2 O-MgO system

    CERN Document Server

    Okada, T; Shimomura, O

    2002-01-01

    The diamond formation process in aqueous fluid catalyst under high-pressure and high-temperature conditions has been observed for the first time. Quench experiments and in situ x-ray diffraction experiments using synchrotron radiation have been performed upon a mixture of brucite (Mg(OH) sub 2) and graphite as the starting material. It was confirmed that brucite decomposed into periclase and H sub 2 O at 3.6 GPa and 1050 deg. C while its complete melting occurred at 6.2 GPa and 1150 deg. C, indicating that the solubility of MgO in H sub 2 O greatly increases with increasing pressure. The conversion of carbon from its graphite to its diamond form in aqueous fluid was observed at 7.7 GPa and 1835 deg. C.

  14. Depth probing of the hydride formation process in thin Pd films by combined electrochemistry and fiber optics-based in situ UV/vis spectroscopy.

    Science.gov (United States)

    Wickman, Björn; Fredriksson, Mattias; Feng, Ligang; Lindahl, Niklas; Hagberg, Johan; Langhammer, Christoph

    2015-07-15

    We demonstrate a flexible combined electrochemistry and fiber optics-based in situ UV/vis spectroscopy setup to gain insight into the depth evolution of electrochemical hydride and oxide formation in Pd films with thicknesses of 20 and 100 nm. The thicknesses of our model systems are chosen such that the films are thinner or significantly thicker than the optical skin depth of Pd to create two distinctly different situations. Low power white light is irradiated on the sample and analyzed in three different configurations; transmittance through, and, reflectance from the front and the back side of the film. The obtained optical sensitivities correspond to fractions of a monolayer of adsorbed or absorbed hydrogen (H) and oxygen (O) on Pd. Moreover, a combined simultaneous readout obtained from the different optical measurement configurations provides mechanistic insights into the depth-evolution of the studied hydrogenation and oxidation processes.

  15. Optimisation of polishing processes by using iTIRM for in-situ monitoring of surface quality

    NARCIS (Netherlands)

    Meeder, M.; Mauret, T.; Booij, S.; Braat, J.; Faehnle, O.

    2003-01-01

    The possibilities of iTIRM, an in-process surface measurement tool, are explored in this research. Experiments are done to test the applicability for qualifying and optimising finishing processes for optical surfaces. Several optical glasses, different polishing agents and ductile grinding are inclu

  16. Quantitative fluorescent in-situ hybridization: a hypothesized competition mode between two dominant bacteria groups in hydrogen-producing anaerobic sludge processes.

    Science.gov (United States)

    Huang, C-L; Chen, C-C; Lin, C-Y; Liu, W-T

    2009-01-01

    Two hydrogen-producing continuous flow stirred tank reactors (CSTRs) fed respectively with glucose and sucrose were investigated by polymerase chain reaction-denatured gradient gel electrophoresis (PCR-DGGE) and fluorescent in-situ hybridization (FISH). The substrate was fed in a continuous mode decreased from hydraulic retention time (HRT) 10 hours to 6, 5, 4, 3, and 2 hours. Quantitative fluorescent in-situ hybridization (FISH) observations further demonstrated that two morphotypes of bacteria dominated both microbial communities. One was long rod bacteria which can be targeted either by Chis150 probe designed to hybridize the gram positive low G + C bacteria or the specific oligonucleotide probe Lg10-6. The probe Lg10-6, affiliated with Clostridium pasteurianum, was designed and then checked with other reference organisms. The other type, unknown group, which cannot be detected by Chis150 was curved rod bacteria. Notably, the population ratios of the two predominant groups reflected the different operational performance of the two reactors, such as hydrogen producing rates, substrate turnover rates and metabolites compositions. Therefore, a competition mode of the two dominant bacteria groups was hypothesized. In the study, 16S rRNA-based gene library of hydrogen-producing microbial communities was established. The efficiency of hydrogen yields was correlated with substrates (glucose or sucrose), HRT, metabolites compositions (acetate, propionate, butyrate and ethanol), thermal pre-treatment (seed biomass was heated at 100 degrees C for 45 minutes), and microbial communities in the bioreactor, not sludge sources (municipal sewage sludge, alcohol-processing sludge, or bean-processing sludge). The designed specific oligonucleotide probe Lg10-6 also provides us a useful and fast molecular tool to screen hydrogen-producing microbial communities in the future research.

  17. In situ 7Li and 133Cs nuclear magnetic resonance investigations on the role of Cs+ additive in lithium-metal deposition process

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Jian Zhi; Zhao, Zhenchao; Hu, Mary Y.; Feng, Ju; Deng, Xuchu; Chen, Xilin; Xu, Wu; Liu, Jun; Zhang, Ji-Guang

    2016-02-01

    Application of Li metal electrode in rechargeable lithium battery is hindered by safety concerns due to dendritic growth on the electrode over several charge-discharge cycles. We have found previously that adding low concentration Cs+ in electrolytes can promote smooth deposition of lithium onto metal electrode during repeated charge-discharge cycling using idea Li|Cu battery without the using of a separator. In this work, quantitative in situ 7Li and 133Cs NMR investigations using real planar symmetric lithium battery cells with and without Cs+ additives were carried out. It is found that the deposited lithium atoms on electrodes are highly porous. Detailed analysis of the data were carried out by separating the 7Li signal from deposited lithium that was oriented parallel to the electrode surface with the signal from the Li-metal nanorodes oriented perpendicular or nearly perpendicular to the electrode surface. The results demonstrate that addition of Cs+ can significantly enhance both the formation of uniform Li nanorods, and the reversibility of electrode. In situ 133Cs NMR directly confirms that Cs+ migrates to the electrode to form a positively charged electrostatic shield during cycling process. Combining the quantitative analysis of the orientation dependent signals of deposited metal Li and previous ex-situ results, different Li deposition models are proposed. During cycling process, more “active” lithium participates in the Li transfer between the electrode and nanorods for the battery with Cs+, while for the battery without Cs+ more dead and thinker lithium rods are formed and Li transfer between dendrites from different electrodes dominates.

  18. Mercury and toxic metals in ash from combustion and incineration processes; Mercurio y metales toxicos en cenizas provenientes de procesos de combustion e incineracion

    Energy Technology Data Exchange (ETDEWEB)

    Mugica, V.; Amador, M.A.; Torres, M.; Figueroa, J. de J. [Universidad Autonomo-Metropolitana-Azcapotzalco, Reynosa (Mexico)

    2003-07-01

    In Mexico, most of the ashes from combustion and incineration process were not appropriately disposed, they are either left on industrial yards and cliffs or thrown away in open spaces and then carried by the wind to places where they can harm population, affect aquatic environment or soils. For prevention and control, the knowledge on the concentration of trace elements in waste ashes is necessary. In this study, several oxidation methods for digestion of ashes followed by inductively coupled plasma emission spectrometry were evaluated. Hg, Cd, Cr, Cu, Ni, Pb and V were determined in ashes from coal and fuel oil combustion, as well as in ashes from the incineration of municipal, water treatment sludge, and medical wastes. Results showed important concentrations of different trace elements in the ashes. This suggests that adequate disposal of these wastes should be mandatory. On the other hand, concentration of trace elements in the leachates indicated that these wastes are not toxic and they could be disposed in sanitary landfill. 23 refs.

  19. Monitoring temperatures in coal conversion and combustion processes via ultrasound. [Ultrasonic thermometry proposal

    Energy Technology Data Exchange (ETDEWEB)

    Gopalsami, N.; Raptis, A. C.; Mulcahey, T. P.

    1980-02-01

    A study of the state-of-the-art of instrumentation for monitoring temperatures in coal conversion and combustion systems has been carried out. The instrumentation types studied include Thermocouples, Radiation Pyrometers, and Acoustical Thermometers. The capabilities and limitations of each type are reviewed. The study determined that ultrasonic thermometry has the potential of providing viable instrumentation. Consequently, a feasibility study of the ultrasonic thermometry was undertaken. A mathematical model of a pulse-echo ultrasonic temperature measurement system is developed using linear system theory. The mathematical model lends itself to the adaptation of generalized correlation techniques for the estimation of propagation delays. Computer simulations are made to test the efficacy of the signal processing techniques for noise-free as well as noisy signals. Based on the theoretical study, acoustic techniques to measure temperature in reactors and combustors are feasible. To experimentally verify the technique it is needed (a) to test the available sensor materials at high temperatures under erosive and corrosive conditions and (b) upon the selection of the appropriate sensor material to validate the proposed signal processing technique. The base for the applicability of this technique will be the frequency of operation, which will determine the length of the sensor and the noise background at the frequency of interest. It is, however, believed that the proposed technique will provide reliable estimates under the noise background.

  20. Sandia Combustion Research: Technical review

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    This report contains reports from research programs conducted at the Sandia Combustion Research Facility. Research is presented under the following topics: laser based diagnostics; combustion chemistry; reacting flow; combustion in engines and commercial burners; coal combustion; and industrial processing. Individual projects were processed separately for entry onto the DOE databases.

  1. New methods of in situ metrology and process control for EBF3 Additive Manufacturing, a feasibility study Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation is a methodology for advanced process control and deposition analysis built around using signals generated by beam-component interactions in...

  2. Ceramic Heat Exchangers and Chemical Reactors with Micro-Scale Features for In-Situ Resource Processing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — It is proposed to develop compact and lightweight ceramic heat exchangers and chemical reactors suitable for high temperature processes. These devices will have...

  3. Analysis of the organic contaminants in the condensate produced in the in situ underground coal gasification process.

    Science.gov (United States)

    Smoliński, Adam; Stańczyk, Krzysztof; Kapusta, Krzysztof; Howaniec, Natalia

    2013-01-01

    Addressing the environmental risks related to contamination of groundwater with the phenolics, benzene, toluene, ethyl benzene, xylene (BTEX) and polycyclic aromatic hydrocarbons (PAHs), which might be potentially released from the underground coal gasification (UCG) under adverse hydrogeological and/or operational conditions, is crucial in terms of wider implementation of the process. The aim of this study was to determine the main organic pollutants present in the process condensate generated during the UCG trial performed on hard coal seam in the Experimental Mine 'Barbara', Poland; 8,933 L of condensate was produced in 813 h of experiment duration (including 456 h of the post-process stage) with average phenolics, BTEX and PAH concentrations of 576,000, 42.3 and 1,400.5 μg/L, respectively. The Hierarchical Clustering Analysis was used to explore the differences and similarities between the samples. The sample collected during the first 48 h of the process duration was characterized by the lowest phenanthrene, anthracene, fluoranthene and pyrene contents, high xylene content and the highest concentrations of phenolics, benzene, toluene and ethyl benzene. The samples collected during the stable operation of the UCG process were characterized by higher concentrations of naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, while in the samples acquired in the post-process stage the lowest concentrations of benzene, toluene, naphthalene, acenaphthene and fluorene were observed.

  4. Risk Assessment of a Post-Combustion and Amine-Based CO2 Capture Ready Process

    Directory of Open Access Journals (Sweden)

    Alicja Krzemień

    2013-01-01

    Full Text Available CO2 Capture Ready Process, as a part of Carbon Capture and Storage (CCS technology, is a response to international political pressure and the priority of the European Commission to reduce anthropogenic CO2 emissions since it is connected with concerns regarding global warming. This is currently considered as an option for lessing CO2 emissions into the atmosphere. Many laboratory experiments, as well as pilot projects, have been carried out using different capture systems, but until now no experience from the one-to-one size operational installation has been gained. The energy industry must meet several challenges associated with the start-up of the new full-scale project. This paper investigates the problems that can occur while linking a new technology like the CO2 Capture Ready Process to a working fossil fuel power plant. A Hazard and Operability study (HAZOP has been used, as it is a structured and systematic examination of a planned or existing process or operation, in order to identify and evaluate problems that may represent risks to personnel or equipment. A case study of a post-combustion CO2 capture system with an aqueous monoethanolamine as a solvent is presented, as it is the most likely system to be used in Polish power plants. Basic problems in the analysis as well as the parameters that should be considered to determine vulnerabilities of the process were successfully identified. Gaining experience about the installation’s behaviour while connected to the existing equipment of any power plant is critical for future CCS projects.

  5. In-situ synthesis of AgCu/Cu{sub 2}O nanocomposite by mechanical alloying: The effect of the processing on the thermal behavior

    Energy Technology Data Exchange (ETDEWEB)

    Gingu, Oana [University of Craiova, Department IMST, 1st Calugareni, 220037 Drobeta Turnu Severin (Romania); Rotaru, P., E-mail: protaru@central.ucv.ro [University of Craiova, Department of Physics, 13 A.I. Cuza Street, 200585 Craiova (Romania); Milea, A.; Marin, A. [Institute of Physical Chemistry “Ilie Murgulescu” of the Romanian Academy, 202 Splaiul Independentei, P.O. Box 194, 060021 Bucharest (Romania); Nicolicescu, C.; Sima, Gabriela [University of Craiova, Department IMST, 1st Calugareni, 220037 Drobeta Turnu Severin (Romania); Tanasescu, Speranta [Institute of Physical Chemistry “Ilie Murgulescu” of the Romanian Academy, 202 Splaiul Independentei, P.O. Box 194, 060021 Bucharest (Romania)

    2015-04-20

    TG heating curves for Ag–Cu samples vs. the milling time, recorded during the heating. The samples’ mass variation is strongly dependent on the powders’ specific surface, respectively the milling time. - Highlights: • AgCu bimetallic composites reinforced by Cu{sub 2}O has been studied. • The milling time influences the particle size distribution of the particles. • The thermal behavior of the mixtures has been studied by TG and DSC, in argon. • Correlation of thermal stability with thermal expansion properties was made. - Abstract: The influence of the mechanical alloying processing parameters on the elaboration of AgCu-based bimetallic matrix composites reinforced by in-situ synthesized Cu{sub 2}O has been studied. The milling time (20, 45 and 80 h) of the initial 72% mass Ag + 28% mass Cu micrometric powders mixture influences the particle size distribution of the obtained composite particles. After 80 h of mechanical alloying, AgCu/Cu{sub 2}O nanoparticles of 60–80 nm are obtained and their chemical composition at bulk/surface level has been determined by X-ray diffraction and photoelectron spectroscopy. The effect of milling time on the thermal behavior of the powders samples has been studied by thermogravimetry and differential scanning calorimetry measurements in argon atmosphere. The argon chemosorbtive reaction from the particles surface has been identified and the binding energy (0.9–1.99 eV) has been calculated. The isothermal drop calorimetry and the linear thermal expansion measurements were used to evaluate the correlation between thermal stability and thermal expansion properties of the in-situ synthesized AgCu/Cu{sub 2}O nanocomposite.

  6. Estimating the greenhouse gas fluxes of European grasslands with a process-based model: 1. Model evaluation from in situ measurements

    Science.gov (United States)

    Vuichard, Nicolas; Soussana, Jean-FrançOis; Ciais, Philippe; Viovy, Nicolas; Ammann, Christof; Calanca, Pierluigi; Clifton-Brown, John; Fuhrer, Jürg; Jones, Mike; Martin, CéCile

    2007-03-01

    We improved a process-oriented biogeochemical model of carbon and nitrogen cycling in grasslands and tested it against in situ measurements of biomass and CO2 and CH4 fluxes at five European grassland sites. The new version of the model (PASIM) calculates the growth and senescence of aboveground vegetation biomass accounting for sporadic removals when the grassland is cut and for continuous removals when it is grazed. Limitations induced by high leaf area index (LAI), soil water deficits and aging of leaves are also included. We added to this a simple empirical formulation to account for the detrimental impact on vegetation of trampling and excreta by grazing animals. Finally, a more realistic methane emission module than is currently used was introduced on the basis of the quality of the animals' diet. Evaluation of this improved version of PASIM is performed at (1) Laqueuille, France, on grassland continuously grazed by cattle with two plots of intensive and extensive grazing intensities, (2) Oensingen, Switzerland, on cut grassland with two fertilized and nonfertilized plots, and (3) Carlow, Ireland, on grassland that is both cut and grazed by cattle during the growing season. In addition, we compared the modeled animal CH4 emissions with in situ measurements on cattle for two grazing intensities at the grazed grassland site of Laqueuille. Altogether, when all improvements to the PASIM model are included, we found that the new parameterizations resulted into a better fit to the observed seasonal cycle of biomass and of measured CO2 and CH4 fluxes. However, the large uncertainties in measurements of biomass and LAI make simulation of biomass dynamics difficult to make. Also simulations for cut grassland are better than for grazed swards. This work paves the way for simulating greenhouse gas fluxes over grasslands in a spatially explicit manner, in order to quantify and understand the past, present and future role of grasslands in the greenhouse gas budget of the

  7. Optimization of friction stir welding process to maximize tensile strength of AA6061/ZrB2 in-situ composite butt joints

    Science.gov (United States)

    Dinaharan, I.; Murugan, N.

    2012-02-01

    A variety of ceramic particles is added to aluminum alloys to produce aluminum matrix composites (AMCs). Establishing the joining procedure for AMCs is an essential requirement prior to extending their applications. Friction stir welding (FSW) is an emerging solid state welding which eliminates all the defects associated with fusion welding of AMCs. An attempt has been made to friction stir weld AA6061/ ZrB2 in-situ composite. A four factor, five level central composite rotatable design has been used to minimize the number of experiments. The four factors considered are tool rotational speed, welding speed, axial force and weight percentage of ZrB2. A mathematical model has been developed incorporating the FSW process parameters to predict the ultimate tensile strength (UTS) and FS process is optimized using generalized reduced gradient method (GRG) to maximize the UTS. The effect of process parameters on UTS was analyzed. It was observed that the process parameters independently influence the UTS over the entire range studied in this work.

  8. In situ measurement using FBGs of process-induced strains during curing of thick glass/epoxy laminate plate

    DEFF Research Database (Denmark)

    Nielsen, Michael Wenani; Schmidt, Jacob Wittrup; Hattel, Jesper Henri;

    2012-01-01

    For large composite structures, such as wind turbine blades, thick laminates are required to withstand large in-service loads. During the manufacture of thick laminates, one of the challenges met is avoiding process-induced shape distortions and residual stresses. In this paper, embedded fibre...

  9. In situ identification of polyphosphate- and polyhydroxyalkanoate-accumulating traits for microbial populations in a biological phosphorus removal process

    DEFF Research Database (Denmark)

    Liu, W.-T.; Nielsen, Alex Toftgaard; Wu, JH

    2001-01-01

    Polyphosphate- and polyhydroxyalkanoate (PHA)- accumulating traits of predominant microorganisms in an efficient enhanced biological phosphorus removal (EBPR) process were investigated systematically using a suite of non-culture-dependent methods. Results of 16S rDNA clone library and fluorescence...

  10. In situ observation of the formation process for free-standing Au nanowires with a scanning electron microscope

    Science.gov (United States)

    Aiba, Akira; Kaneko, Satoshi; Fujii, Shintaro; Nishino, Tomoaki; Tsukagoshi, Kazuhito; Kiguchi, Manabu

    2017-03-01

    We have developed a simultaneous electronic and structural characterization method for studying the formation process for Au nanowires. The method is based on two-probe electronic transport measurement of free-standing Au nanowires and simultaneous structural characterization using scanning electron microscopy (SEM). We measured the electronic currents during the electromigration (EM)-induced narrowing process for the free-standing Au nanowires. A free-standing Au nanowire with a desired conductance value was fabricated by EM. Simultaneous SEM and conductance measurements revealed the EM-induced narrowing process for the Au wires, in which material transfer in the nanowires caused growth towards the positively biased electrode and contact failure at the negatively biased electrode. The narrowed free-standing Au nanowires were stable and could be maintained for more than 10 h without their conductance changing. These results indicate the high stability of the EM-processed Au nanowires compared to Au nanowires fabricated by mechanical elongation or the breaking of Au nanocontacts.

  11. Plasma assisted measurements of alkali metal concentrations in pressurised combustion processes

    Energy Technology Data Exchange (ETDEWEB)

    Hernberg, R.; Haeyrinen, V. [Tampere Univ. of Technology (Finland)

    1997-10-01

    In this project the continuous alkali measurement method plasma excited alkali resonance line spectroscopy (PEARLS) was developed, tested and demonstrated in pressurised combustion facilities. The PEARLS method has been developed at Tampere University of Technology (TUT). During 1994-1996 the PEARLS method was developed from the laboratory level to an industrial prototype. The alkali measuring instrument has been tested and used for regular measurements in four different pressurised combustion installations ranging up to industrial pilot scale. The installations are: (1) a pressurised entrained flow reactor (PEFR) at VTT Energy in Jyvaeskylae, Finland (2) a pressurised fluidised bed combustion facility, called FRED, at DMT in Essen, Germany. (3) a 10 MW pressurised circulating fluidised bed combustion pilot plant at Foster Wheeler Energia Oy in Karhula, Finland (4) PFBC Research Facility at ABB Carbon in Finspaang, Sweden

  12. Fuel-Flexible Combustion System for Refinery and Chemical Plant Process Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Charles; Wilson, Robert

    2014-04-30

    This project culminated in the demonstration of a full-scale industrial burner which allows a broad range of “opportunity” gaseous fuels to be cost-effectively and efficiently utilized while generating minimal emissions of criteria air pollutants. The burner is capable of maintaining a stable flame when the fuel composition changes rapidly. This enhanced stability will contribute significantly to improving the safety and reliability of burner operation in manufacturing sites. Process heating in the refining and chemicals sectors is the primary application for this burner. The refining and chemical sectors account for more than 40% of total industrial natural gas use. Prior to the completion of this project, an enabling technology did not exist that would allow these energy-intensive industries to take full advantage of opportunity fuels and thereby reduce their natural gas consumption. Opportunity gaseous fuels include biogas (from animal and agricultural wastes, wastewater plants, and landfills) as well as syngas (from the gasification of biomass, municipal solid wastes, construction wastes, and refinery residuals). The primary challenge to using gaseous opportunity fuels is that their composition and combustion performance differ significantly from those of conventional fuels such as natural gas and refinery fuel gas. An effective fuel-flexible burner must accept fuels that range widely in quality and change in composition over time, often rapidly. In Phase 1 of this project, the team applied computational fluid dynamics analysis to optimize the prototype burner’s aerodynamic, combustion, heat transfer, and emissions performance. In Phase 2, full-scale testing and refinement of two prototype burners were conducted in test furnaces at Zeeco’s offices in Broken Arrow, OK. These tests demonstrated that the full range of conventional and opportunity fuels could be utilized by the project’s burner while achieving robust flame stability and very low levels of

  13. Fabrication and processing of next-generation oxygen carrier materials for chemical looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Nadarajah, Arunan [Univ. of Toledo, OH (United States)

    2017-04-26

    Among numerous methods of controlling the global warming effect, Chemical Looping Combustion is known to be the most viable option currently. A key factor to a successful chemical looping process is the presence of highly effective oxygen carriers that enable fuel combustion by going through oxidation and reduction in the presence of air and fuel respectively. In this study, CaMnO3-δ was used as the base material and doped on the A-site (Sr or La) and B-site (Fe, Ti, Zn and Al) by 10 mol % of dopants. Solid state reaction followed by mechanical extrusion (optimized paste formula) was used as the preparation method A series of novel doped perovskite-type oxygen carrier particles (CaxLa (Or Sa)1-x Mn1-yByO3-δ (B-site = Fe, Ti, Al, or Zr)) were synthesized by the proposed extrusion formula. The produced samples were characterized with XRD, SEM, BET and TGA techniques. According to the results obtained from TGA analysis, the oxygen capacity of the samples ranged between 1.2 for CLMZ and 1.75 for CSMF. Reactivity and oxygen uncoupling behaviors of the prepared samples were also evaluated using a fluidized bed chemical looping reactor using methane as the fuel at four different temperatures (800, 850, 900, 950 °C). All of the oxygen carriers showed oxygen uncoupling behavior and they were able to capture and release oxygen. Mass-based conversion of the perovskites was calculated and temperature increase proved to increase the mass-based conversion rate in all of the samples under study. Gas yield was calculated at 950 °C as well, and results showed that CLMZ, CM and CSMF showed 100% gas yields and CLMF and CSMZ showed approximately 85% yield in fluidized bed reactor, which is a high and acceptable quantity. Based on extended reactor tests the modified calcium manganese perovskite structures (CSMF) can be a good candidate for future pilot tests.

  14. Ozone formation in relation with combustion processes in highly populated urban areas

    Directory of Open Access Journals (Sweden)

    Pasquale Avino

    2015-07-01

    Full Text Available The complex chain of photochemical reactions is one of the most important tasks in the air quality evaluation, expecially in urban areas. In fact, in this case there are high emission levels of NOx and no-methane hydrocarbons by combustion processes such as autovehicular traffic, domestic heating and industrial plants. Ozone is not emitted directly into the atmosphere but it is formed from a complex series of reactions between emitted nitrogen oxides (NOx and reactive organic compounds (ROC. The high ozone concentrations, which occur during photochemical episodes, are usually accompanied by elevated concentrations of other photochemical oxidants such as nitric acid (HNO3, peroxyacylnitrates (PANs, hydrogen peroxide (H2O2, etc. The complex series of these reactions constitutes the most important issue to the degradation of air quality. Further, the NMHCs play a key role in the formation of photochemical air pollution: they are considered as precursors for ozone production at the ground level when the sunlight and nitrogen oxides are present. From a practically point of view defining a quality standard or a limit is substantially correct but it is no sufficient to solve the problem. So it should become necessary to acquire knowledge on the different formation mechanisms of the photochemical pollution phenomena. In this paper there will be shown the results of a long-term study performed in Rome for evaluating the ozone formation in relationship with the autovehicular traffic density.

  15. Chemical looping combustion in a rotating bed reactor--finding optimal process conditions for prototype reactor.

    Science.gov (United States)

    Håkonsen, Silje Fosse; Blom, Richard

    2011-11-15

    A lab-scale rotating bed reactor for chemical looping combustion has been designed, constructed, and tested using a CuO/Al(2)O(3) oxygen carrier and methane as fuel. Process parameters such as bed rotating frequency, gas flows, and reactor temperature have been varied to find optimal performance of the prototype reactor. Around 90% CH(4) conversion and >90% CO(2) capture efficiency based on converted methane have been obtained. Stable operation has been accomplished over several hours, and also--stable operation can be regained after intentionally running into unstable conditions. Relatively high gas velocities are used to avoid fully reduced oxygen carrier in part of the bed. Potential CO(2) purity obtained is in the range 30 to 65%--mostly due to air slippage from the air sector--which seems to be the major drawback of the prototype reactor design. Considering the prototype nature of the first version of the rotating reactor setup, it is believed that significant improvements can be made to further avoid gas mixing in future modified and up-scaled reactor versions.

  16. Investigating combustion as a method of processing inedible biomass produced in NASA's biomass production chamber

    Science.gov (United States)

    Dreschel, T. W.; Wheeler, R. M.; Hinkle, C. R.; Sager, J. C.; Knott, W. M.

    1991-01-01

    The Controlled Ecological Life Support System (CELSS) Breadboard Project at the John F. Kennedy Space Center is a research program to integrate and evaluate biological processes to provide air, water, and food for humans in closed environments for space habitation. This project focuses on the use of conventional crop plants as grown in the Biomass Production Chamber (BPC) for the production and recycling of oxygen, food, and water. The inedible portion of these crops has the potential to be converted to edible biomass or directly to the elemental constituents for direct recycling. Converting inedible biomass directly, by combustion, to carbon dioxide, water, and minerals could provide a baseline for estimating partitioning of the mass balance during recycling in a CELSS. Converting the inedible biomass to carbon dioxide and water requires the same amount of oxygen that was produced by photosynthesis. The oxygen produced during crop growth is just equal to the oxygen required to oxidize all the biomass produced during growth. Thus, the amount of oxygen produced that is available for human consumption is in proportion to the amount of biomass actually utilized by humans. The remaining oxygen must be available to oxidize the rest of the biomass back to carbon dioxide and water or the system will not be a regenerative one.

  17. Multivariable Optimization of the Piperazine CO2 Post-Combustion Process

    DEFF Research Database (Denmark)

    Gaspar, Jozsef; von Solms, Nicolas; Thomsen, Kaj

    2016-01-01

    8 molal piperazine (PZ) is a promising solvent for developing an energy efficient CO2 post-combustion capture process. However, it has a limited operating range due to precipitation. The operating range can be extended by decreasing the piperazine concentration and/or increasing the CO2 loading...... which accounts for precipitation when estimating the heat and mass transfer rates. The results show that the 7 molal piperazine gives the lowest specific reboiler duty at 0.40 CO2 lean loading: 3.32 GJ/t CO2 and 4.05 GJ/t CO2 for the ASC case and NGCC cases. The analysis also reveals that the capture.......2 to 0.6 lean loading, and for two flue gas sources: natural gas combined cycle power plant (NGCC, 3.9 mol% CO2) and a coal based power plant (ASC, 13.25 mol% CO2). Special attention is given to the boundaries where precipitation may occur. The results are created by the hybrid CAPCO2 rate-based model...

  18. Mechanical signature analysis using time-frequency signal processing: Application to internal combustion engine knock detection

    Energy Technology Data Exchange (ETDEWEB)

    Samimy, B. [Ford Motor Co., Dearborn, MI (United States). Advanced Vehicle Technology Div.; Rizzoni, G. [Ohio State Univ., Columbus, OH (United States)

    1996-09-01

    Signature analysis consists of the extraction of information from measured signal patterns. The work presented in this paper illustrates the use of time-frequency (TF) analysis methods for the purpose of mechanical signature analysis. Mechanical signature analysis is a mature and developed field; however, TF analysis methods are relatively new to the field of mechanical signal processing, having mostly been developed in the present decade, and have not yet been applied to their full potential i this field of engineering applications. Some of the ongoing efforts are briefly reviewed in this paper. One important application of TF mechanical signature analysis is the diagnosis of faults in mechanical systems. In this paper the authors illustrate how the use of joint TF signal representations can result in tangible benefits when analyzing signatures generated by transient phenomena in mechanical systems, such as might be caused by faults or otherwise abnormal operation. This paper also explores signal detection concepts in the joint TF domain and presents their application to the detection of internal combustion engine knock.

  19. Process design of in situ esterification-transesterifica tion for biodiesel production from residual oil of spent bleaching earth (SBE)

    Science.gov (United States)

    Suryani, A.; Mubarok, Z.; Suprihatin; Romli, M.; Yunira, E. N.

    2017-05-01

    Indonesia is the largest producer of Crude Palm Oil (CPO) in the world. CPO refining process produces spent bleaching earth (SBE), which still contains 20-30% oil. This residual oil is very potential to be developed as a biodiesel feedstock. The purpose of this research was to develop an in situbiodiesel production process of residual oil of SBE, which covered stirring speed of esterification and transesterification and also transesterification time to produce biodiesel with the best characteristics. The production was conducted in a 100 L reactor. The stirring speeds applied were 650 rpm and 730 rpm, and the transesterification time varied at 60, 90 and 120 minutes. The combination of 730 rpm stirring speed for 90 minutes transesterification resulted in the best biodiesel characteristics with the yield of 85%, the specific energy of 6,738 kJ/kg and the heater efficiency of 48%. The physico-chemical properties of biodiesel was in conformity with the SNI of Biodiesel.

  20. The byssus of the zebra mussel, Dreissena polymorpha. I: Morphology and in situ protein processing during maturation.

    Science.gov (United States)

    Rzepecki, L M; Waite, J H

    1993-10-01

    The zebra mussel, Dreissena polymorpha, owes its notoriety as a biofouler to its adhesive skills and opportunism. Adhesion by the adult mussel to hard substrata is mediated by a nonliving extracorporeal structure called the byssus, which is superficially similar to the byssus of marine mussels in that it consists of a tight bundle of sclerotized threads tipped by adhesive plaques. Juvenile zebra mussels secrete a homologous structure on settlement, but they also employ an elongated belaying byssus while climbing that consists of an elastic, mucous filament anchored at irregular intervals by a byssal thread and plaque. This multiply anchored belaying line can be 20 to 30 times the mussel length. Histochemical tests show that the thread and plaque of both kinds of byssus contains a complex distribution of proteins that are subject to chemical processing after secretion. This processing may result from the formation of crosslinks following the catecholoxidase-catalyzed oxidation of peptidyl 3,4-dihydroxyphenylalanine during sclerotization.

  1. Statistical Optimization of process parameters for SiO2-Nickel nanocomposites by in-situ reduction

    Directory of Open Access Journals (Sweden)

    A.K.Pramanick

    2015-06-01

    Full Text Available The optimum combination of process parameters - temperature, time of reduction under nitrogen atmosphere and amount of NiCl2 was delineated to find the maximum yield of nanocrystallite Ni in the synthesized silica gel matrix. A statistically adequate regression equation, within 95% confidence limit was developed by carrying out a set of experiments within the framework of design of experiment. The regression equation is found to indicate the beneficial role of the temperature and time of reduction.

  2. Sonar In-Situ Mode Assessment System (SIMAS) AN/UYQ-25 Data Processing System Software Life Cycle Support Plan.

    Science.gov (United States)

    1980-02-01

    conjunction with SSSMPG and is to be used on an interim basis until implementation of the POST PROCESSOR with the .TASS System Generator . 8. System ...in hard copy output of AN/UYQ-25. 12. Post Processor ( ) - converts output of MTASS system generator to format of input to loaders; written in Fortran... Generator (SSS )GEN) - produces a bootable system tape from (1) a library of modules which have been processed through OISPR, and in conjunction with (2) a

  3. Mineral processing technologies used to obtain valuable components of the solid wastes from coal combustion in power plants

    Directory of Open Access Journals (Sweden)

    Martin Sisol

    2005-11-01

    Full Text Available This paper presents mineral processing technologies used to achieve components from solid wastes of coal combusted in power plants. By combusting bituminous coal in smelting boilers, mineral novelties are formed which are separable by suitable mineral processing technologies. The separation of unburned coal residues is realized by flotation, using nonionic flotation agents such as Flotalex MR, Flotalex bio, Flotakol NX and others. The Fe component created by the mineral novelty of magnetite is obtained by wet and dry low-intensity magnetic separation. Optimal results were accomplished by the flotation process in which we obtained residues of unburned coal. The waste from the flotation was consequently separated by the wet low-intensity separation. The waste from the flotation and magnetic separation - subtilized fly ash, contained 0 – 2,5% LOI which can be used in architecture.

  4. Investigation of the geokinetics horizontal in situ oil shale retorting process. Quarterly report, April, May, June 1980

    Energy Technology Data Exchange (ETDEWEB)

    Hutchinson, D.L.

    1980-08-01

    The Retort No. 18 burn was terminated on May 11, 1980. A total of 5547 barrels of shale oil or 46 percent of in-place resource was recovered from the retort. The EPA-DOE/LETC post-burn core sampling program is underway on Retort No. 16. Eleven core holes (of 18 planned) have been completed to date. Preliminary results indicate excellent core recovery has been achieved. Recovery of 702 ft of core was accomplished. The Prevention of Significant Deterioration (PSD) permit application was submitted to the EPA regional office in Denver for review by EPA and Utah air quality officials. The application for an Underground Injection Control (UIC) permit to authorize GKI to inject retort wastewater into the Mesa Verde Formation is being processed by the State of Utah. A hearing before the Board of Oil, Gas and Mining is scheduled in Salt Lake City, Utah, for July 22, 1980. Re-entry drilling on Retort No. 24 is progressing and placement of surface equipment is underway. Retort No. 25 blasthole drilling was completed and blast preparations are ongoing. Retort No. 25 will be blasted on July 18, 1980. The retort will be similar to Retort No. 24, with improvements in blasthole loading and detonation. US Patent No. 4,205,610 was assigned to GKI for a shale oil recovery process. Rocky Mountain Energy Company (RME) is evaluating oil shale holdings in Wyoming for application of the GKI process there.

  5. Personalized implant for high tibial opening wedge: combination of solid freeform fabrication with combustion synthesis process.

    Science.gov (United States)

    Zhim, Fouad; Ayers, Reed A; Moore, John J; Moufarrège, Richard; Yahia, L'Hocine

    2012-09-01

    In this work a new generation of bioceramic personalized implants were developed. This technique combines the processes of solid freeform fabrication (SFF) and combustion synthesis (CS) to create personalized bioceramic implants with tricalcium phosphate (TCP) and hydroxyapatite (HA). These porous bioceramics will be used to fill the tibial bone gap created by the opening wedge high tibial osteotomy (OWHTO). A freeform fabrication with three-dimensional printing (3DP) technique was used to fabricate a metallic mold with the same shape required to fill the gap in the opening wedge osteotomy. The mold was subsequently used in a CS process to fabricate the personalized ceramic implants with TCP and HA compositions. The mold geometry was designed on commercial 3D CAD software. The final personalized bioceramic implant was produced using a CS process. This technique was chosen because it exploits the exothermic reaction between P₂O₅ and CaO. Also, chemical composition and distribution of pores in the implant could be controlled. To determine the chemical composition, the microstructure, and the mechanical properties of the implant, cylindrical shapes were also fabricated using different fabrication parameters. Chemical composition was performed by X-ray diffraction. Pore size and pore interconnectivity was measured and analyzed using an electronic microscope system. Mechanical properties were determined by a mechanical testing system. The porous TCP and HA obtained have an open porous structure with an average 400 µm channel size. The mechanical behavior shows great stiffness and higher load to failure for both ceramics. Finally, this personalized ceramic implant facilitated the regeneration of new bone in the gap created by OWHTO and provides additional strength to allow accelerated rehabilitation.

  6. Integration between a demo size post-combustion CO2 capture and full size power plant: an integral approach on energy penalty for different process options

    NARCIS (Netherlands)

    Miguel Mercader, F. de; Magneschi, G.; Sanchez Fernandez, E.; Stienstra, G.J.; Goetheer, E.L.V.

    2012-01-01

    CO2 capture based on post-combustion capture has the potential to significantly reduce the CO2 emissions from coal-fired power plants. However, this capture process reduces considerably the energy efficiency of the power plant. To reduce this energy penalty, this paper studies different post-combust

  7. Facile Preparation of Highly Conductive Metal Oxides by Self-Combustion for Solution-Processed Thermoelectric Generators.

    Science.gov (United States)

    Kang, Young Hun; Jang, Kwang-Suk; Lee, Changjin; Cho, Song Yun

    2016-03-01

    Highly conductive indium zinc oxide (IZO) thin films were successfully fabricated via a self-combustion reaction for application in solution-processed thermoelectric devices. Self-combustion efficiently facilitates the conversion of soluble precursors into metal oxides by lowering the required annealing temperature of oxide films, which leads to considerable enhancement of the electrical conductivity of IZO thin films. Such enhanced electrical conductivity induced by exothermic heat from a combustion reaction consequently yields high performance IZO thermoelectric films. In addition, the effect of the composition ratio of In to Zn precursors on the electrical and thermoelectric properties of the IZO thin films was investigated. IZO thin films with a composition ratio of In:Zn = 6:2 at the low annealing temperature of 350 °C showed an enhanced electrical conductivity, Seebeck coefficient, and power factor of 327 S cm(-1), 50.6 μV K(-1), and 83.8 μW m(-1) K(-2), respectively. Moreover, the IZO thin film prepared at an even lower temperature of 300 °C retained a large power factor of 78.7 μW m(-1) K(-2) with an electrical conductivity of 168 S cm(-1). Using the combustive IZO precursor, a thermoelectric generator consisting of 15 legs was fabricated by a printing process. The thermoelectric array generated a thermoelectric voltage of 4.95 mV at a low temperature difference (5 °C). We suggest that the highly conductive IZO thin films by self-combustion may be utilized for fabricating n-type flexible printed thermoelectric devices.

  8. Electrical and optical properties of NdAlO{sub 3} synthesized by an optimized combustion process

    Energy Technology Data Exchange (ETDEWEB)

    Harilal, Midhun [Department of Physics, University College, University of Kerala, Trivandrum 695 101 (India); Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, 26300 Kuantan, Pahang (Malaysia); Nair, V. Manikantan; Wariar, P.R.S. [Department of Physics, University College, University of Kerala, Trivandrum 695 101 (India); Padmasree, K.P. [CINVESTAV, Saltillo (Mexico); Yusoff, Mashitah M. [Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, 26300 Kuantan, Pahang (Malaysia); Central Laboratory, Universiti Malaysia Pahang (Malaysia); Jose, Rajan, E-mail: rjose@ump.edu.my [Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, 26300 Kuantan, Pahang (Malaysia)

    2014-04-01

    Nanocrystals of neodymium aluminate (NdAlO{sub 3}) are synthesized using an optimized single step auto-ignition citrate complex combustion process. The combustion product was characterized by X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy and Ultraviolet–visible reflection spectroscopy. The combustion product is single phase and composed of aggregates of nanocrystals of sizes in the range 20–40 nm. The NdAlO{sub 3} crystallized in rhombohedral perovskite structure with lattice parameters a = 5.3223 Å and c = 12.9292 Å. The absorption spectrum of the NdAlO{sub 3} nanocrystals shows characteristic absorption bands of the Nd atom. The polycrystalline fluffy combustion product is sintered to high density (∼ 97%) at ∼ 1450 °C for 4 h and the microstructure was characterized by scanning electron microscopy. The electrical properties of the sintered product were studied using dielectric measurements. The sintered NdAlO{sub 3} has a dielectric constant (ε{sub r}) and a dielectric loss (tan δ) of 21.9 and ∼ 10{sup −3} at 5 MHz, respectively. - Highlights: • NdAlO{sub 3} nanocrystals were synthesized through a citrate combustion process. • The nanocrystals were sintered to ∼ 97% of theoretical density. • The materials were characterized using a number of analytical techniques. • Nanostructured NdAlO{sub 3} showed crystal field splitting of Nd ions. • Dielectric properties of the sintered NdAlO{sub 3} ceramics were studied.

  9. In situ formation of reduced graphene oxide structures in ceria by combined sol-gel and solvothermal processing.

    Science.gov (United States)

    Yang, Jingxia; Ofner, Johannes; Lendl, Bernhard; Schubert, Ulrich

    2016-01-01

    Raman and IR investigations indicated the presence of reduced graphene oxide (rGO)-like residues on ceria nanoparticles after solvothermal treatment in ethanol. The appearance of such structures is closely related to cerium tert-butoxide as precursor and ethanol as solvothermal solvent. The rGO-like residues improve the catalytic CO oxidation activity. This was also confirmed by introduction of "external" graphene oxide during sol-gel processing, by which the rGO structures and the catalytic activity were enhanced.

  10. In situ formation of reduced graphene oxide structures in ceria by combined sol–gel and solvothermal processing

    Directory of Open Access Journals (Sweden)

    Jingxia Yang

    2016-11-01

    Full Text Available Raman and IR investigations indicated the presence of reduced graphene oxide (rGO-like residues on ceria nanoparticles after solvothermal treatment in ethanol. The appearance of such structures is closely related to cerium tert-butoxide as precursor and ethanol as solvothermal solvent. The rGO-like residues improve the catalytic CO oxidation activity. This was also confirmed by introduction of “external” graphene oxide during sol–gel processing, by which the rGO structures and the catalytic activity were enhanced.

  11. Investigation of the geokinetics horizontal in situ oil shale retorting process. Quarterly report, October, November, December 1983

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, K.B.

    1984-03-01

    Retort No. 27 was ignited on August 11, 1983 and by December 31 had completed 139 days of operation and produced 11,420 barrels of oil. Retort No. 28 was ignited on October 18, 1983 and on December 31 had completed 74 days of operation and produced 5,285 barrels of oil. The off-gas processing plants for the two retorts was completed and put through a shakedown run. Concentration levels of H/sub 2/S and NH/sub 3/ in the retort off gas did not warrant plant operation in the fourth quarter. Environmental studies are reported.

  12. In-situ restoration of one-stage partial nitritation-anammox process deteriorated by nitrate build-up via elevated substrate levels

    Science.gov (United States)

    Wang, Xiaolong; Gao, Dawen

    2016-11-01

    The one-stage partial nitritation and anammox process (PN/A) has been a promising microbial process to remove ammonia from wastewater especially with low carbon/nitrogen ratio. The main breakdown was the deterioration caused by overgrowth of nitrite oxidizing bacteria (NOB) resulting effluent nitrate build-up in the PN/A process. This study presented an in-situ restoring strategy for suppressing NOB activity in a one-stage granular PN/A system deteriorated over 2 months, using elevated concentrations of substrates (ammonia and nitrite) under limited dissolved oxygen level. The results showed that the NOB activity was successfully suppressed after 56 days of restoration, and finally the ratio of produced nitrate/consumed ammonium was reduced from 36.8% to 7%. On day 66 the nitrogen removal rate obtained as 1.2 kg N/(m3·d). The high FA level (5–40 mg/L) and low dissolved oxygen (growth, and AOB stay stable, but Nitrospira increase and Nitrobacter declined. High amount of NOB was still persistent in the granules, which was not easy to wash-out and threaten the deammonification performance.

  13. Hybrid perovskite solar cells: In situ investigation of solution-processed PbI2 reveals metastable precursors and a pathway to producing porous thin films

    KAUST Repository

    Barrit, Dounya

    2017-04-17

    The successful and widely used two-step process of producing the hybrid organic-inorganic perovskite CH3NH3PbI3, consists of converting a solution deposited PbI2 film by reacting it with CH3NH3I. Here, we investigate the solidification of PbI2 films from a DMF solution by performing in situ grazing incidence wide angle X-ray scattering (GIWAXS) measurements. The measurements reveal an elaborate sol–gel process involving three PbI2⋅DMF solvate complexes—including disordered and ordered ones—prior to PbI2 formation. The ordered solvates appear to be metastable as they transform into the PbI2 phase in air within minutes without annealing. Morphological analysis of air-dried and annealed films reveals that the air-dried PbI2 is substantially more porous when the coating process produces one of the intermediate solvates, making this more suitable for subsequent conversion into the perovskite phase. The observation of metastable solvates on the pathway to PbI2 formation open up new opportunities for influencing the two-step conversion of metal halides into efficient light harvesting or emitting perovskite semiconductors.

  14. Second-Order Biomimicry: In Situ Oxidative Self-Processing Converts Copper(I)/Diamine Precursor into a Highly Active Aerobic Oxidation Catalyst.

    Science.gov (United States)

    McCann, Scott D; Lumb, Jean-Philip; Arndtsen, Bruce A; Stahl, Shannon S

    2017-04-26

    A homogeneous Cu-based catalyst system consisting of [Cu(MeCN)4]PF6, N,N'-di-tert-butylethylenediamine (DBED), and p-(N,N-dimethylamino)pyridine (DMAP) mediates efficient aerobic oxidation of alcohols. Mechanistic study of this reaction shows that the catalyst undergoes an in situ oxidative self-processing step, resulting in conversion of DBED into a nitroxyl that serves as an efficient cocatalyst for aerobic alcohol oxidation. Insights into this behavior are gained from kinetic studies, which reveal an induction period at the beginning of the reaction that correlates with the oxidative self-processing step, EPR spectroscopic analysis of the catalytic reaction mixture, which shows the buildup of the organic nitroxyl species during steady state turnover, and independent synthesis of oxygenated DBED derivatives, which are shown to serve as effective cocatalysts and eliminate the induction period in the reaction. The overall mechanism bears considerable resemblance to enzymatic reactivity. Most notable is the "oxygenase"-type self-processing step that mirrors generation of catalytic cofactors in enzymes via post-translational modification of amino acid side chains. This higher-order function within a synthetic catalyst system presents new opportunities for the discovery and development of biomimetic catalysts.

  15. Numerical calculation of flow and heat transfer process in the new-type external combustion swirl-flowing hot stove

    Institute of Scientific and Technical Information of China (English)

    Shuchen Zhang; Hongzhi Guo; Xiangjun Liu; Zhangping Cai; Xiancheng Gao; Sidong Xu

    2003-01-01

    It is clarified that the important method to improve the blast temperature of the small and the middle blast furnaces whose production is about two-thirds of total sum of China from 1000℃ to 1250-1300℃ is to preheat both their combustion-supporting air and coal gas. The air temperature of blast furnaces can be reached to 1250-1300℃ by burning single blast furnace coal gas if high speed burner is applied to blast furnaces and new-type external combustion swirl-flowing hot stove is used to preheat their combustion-supporting air. The computational results of the flow and heat transfer processions in the bot stove prove that the surface of the bed of the thernal storage balls there have not eccentric flow and the flow field and temperature field distribution is even. The computational results of the blast temperature distribution are similar to those determination experiment data. The numerical results also provide references for developing and designing the new-type external combustion swirl-flowing hot stoves.

  16. Process for the regeneration of an additive used to control emissions during the combustion of high sulfur fuel

    Energy Technology Data Exchange (ETDEWEB)

    Polanco, D.R.; Bueno, C.O.; Salazar, R.; Chamorra, F.A.S

    1989-05-23

    A process is described for regenerating a sulfur capturing additive used in the preparation of a hydrocarbon in water emulsion for combustion as a fuel comprising: (a) forming a hydrocarbon in water emulsion by admixing a sulfur containing hydrocarbon and water with an emulsifier and a water soluble sulfur capturing additive wherein the sulfur capturing additive is selected from the group consisting of Na/sup +/, K/sup +/, Li/sup +/, Ca/sup ++/, Ba/sup ++/, Mg/sup ++/, Fe/sup +++/ and mixtures thereof; (b) burning the emulsion so as to form a combustion ash containing the water soluble additive as a sulfate compound; (c) leaching the combustion ash wherein the combustion ash is leached with water in a water to ash ratio in ml to grams of 1:1 to 30:1 so as to dissolve the water soluble additive sulfate compound to form a pregnant leach liquor containing the additive; (d) separating the pregnant leach liquor containing the additive; (e) adjusting the pregnant leach liquor with a basic precipitating agent wherein the base precipitating agent is selected from the group consisting of NH/sub 4/OH, NaOH, Ca(OH)/sub 2/, NaCO/sub 3/ and mixtures thereof wherein the pregnant leach liquor is adjusted with the base to a pH of greater than 7 so as to precipitate an additive compound; and (f) recovering the additive compound.

  17. Minimum bed parameters for in situ processing of oil shale. Third quarterly report, April 1-June 30, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Tyner, C. E.

    1980-11-01

    Oil shale retort runs 028 (16% void) and 029 (7% void), composed of competent shale blocks plus shale rubble, were completed. Retort 028, processed with air at a flux of 0.017 kg/sub air//m/sup 2/ /sub shale/.second, had peak temperatures of 700/sup 0/C, a retorting rate of 1.1 m/day, and a yield of 82% FA. Retort 029, processed with air at a flux of 0.027 kg/sub air//m/sup 2//sub shale/.second, had peak temperatures of 750/sup 0/C, a retorting rate of 1.6 m/day, and a yield of 75% FA. Comparisons of retort model calculations with experimental data from previous retort run 027 (16% void, air flux of .029 kg/sub air//m/sup 2//sub shale/.second were good; observed experimental yield was 95% FA, calculated yield, 92.8%; experimental retorting rates varied from 9.5 to 8.9 cm/h, calculated rates from 10.3 to 10.0 cm/h; observed local heating rates ranged from 29 to 14/sup 0/C/h, calculated heating rates from 20 to 16/sup 0/C/h; and observed peak temperatures ranged from 815 to 825/sup 0/C, calculated from 820 to 825/sup 0/C.

  18. Ensuring high quality and efficiency of the worksin the process of constructing the tunnels of in-situ concrete

    Directory of Open Access Journals (Sweden)

    Ginzburg Aleksandr Vladimirovich

    2014-01-01

    Full Text Available In the article the author describes the importance of the technological regulations development in the process of constructing various transport constructions: tunnels, subways, bridges and other important objects. In the article the peculiarities of the technological regulations development are fully taken into account; the dependence of the depth of their development and the quality of the concrete constructions, as well as the speed of the objects of transport infrastructure construction, including the examples of building the road tunnels in Moscow. The course of their development is shown with account for the main provisions, which should be included in technological regulations in order to ensure the most complete coverage of the issues arising in engineering, laboratory and Supervisory structure in the process of performing the works. The author proposes new effective materials and technologies of works. In particular, sufficient attention is paid to self-compacting concrete — a new type of concrete, which is able to flow and compact under its own weight, completely filling the formwork even in case of dense reinforcement, while maintaining the homogeneity and having no seals. The application experience of concrete self-sealing in the construction of the metro showed that labor costs for the concrete mixture sealing were 5-6 times reduced, and the speed of laying the concrete increased 2-3 times. When laying self-compacting concrete high-quality surfaces are formed, which do not require additional costs to bring them to the design parameters. In addition, the work shows the parameters of the technological processes and sets various types of works sequence: the article describes the features of formwork, placement and curing of the concrete in terms of year-round construction, shows the importance of thermo physical calculations of concrete hardening and the efficiency of using self-sealing concrete. Sufficient attention is also paid to

  19. Investigation of combustion and characterization of solid fuels by means of the gas-potentiometric method

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, H.; Trippler, S.; Rau, H. [Otto-von-Guericke University, Magdeburg (Germany). Chemical Inst.

    1998-12-31

    Based on experiences of many years in using solid electrolyte oxygen sensors in gas and oil flames the Gas-Potentiometric Combustion Analysis (GPCA) was developed as a new in-situ method for investigation of the complex processes of solid fuel combustion. It consists of fuel combustion in a fluidized bed reactor and the simultaneous measurement of oxygen consumption due to combustion by placing a gas-potentiometric oxygen sensor immediately in the combustion zone, i.e. the fluidizing bed. For each solid fuel, including relevant waste materials and biofuels, a characteristic oxygen concentration-time curve as a `finger print` is obtained reflecting combustion behaviour. On the basis of the burn-out curves several fuel specific parameters are derivable, e.g. the burn-out time of the fuel sample. By using a specially developed oxygen balance model the effective reaction rate constant and a value for the relative reactivity for comparison of various fuels is obtained. Finally, the overall activation energy for macrokinetics of the whole combustion process can be estimated. The combustion behaviour of a wide range of solid materials (several fuels, waste, biomass) was studied. The surface structure of all materials was studied by using the gas adsorption method (N{sub 2}). The GPCA proved to be a suitable in-situ measuring technique for investigation of solid fuel combustion and a useful method for fuel characterization. A concept for the construction of a `Gas-Potentiometric Combustion Analyzer` as a new device for cheap and fast fuel characterization was developed. 24 refs., 15 figs., 6 tabs.

  20. Nearly Monodispersion CoSm Alloy Nanoparticles Formed by an In-situ Rapid Cooling and Passivating Microfluidic Process

    Directory of Open Access Journals (Sweden)

    Henry Laurence

    2009-01-01

    Full Text Available Abstract An in siturapid cooling and passivating microfluidic processhas been developed for the synthesis of nearly monodispersed cobalt samarium nanoparticles (NPs with tunable crystal structures and surface properties. This process involves promoting the nucleation and growth of NPs at an elevated temperature and rapidly quenching the NP colloids in a solution containing a passivating reagent at a reduced temperature. We have shown that Cobalt samarium NPs having amorphous crystal structures and a thin passivating layer can be synthesized with uniform nonspherical shapes and size of about 4.8 nm. The amorphous CoSm NPs in our study have blocking temperature near 40 K and average coercivity of 225 Oe at 10 K. The NPs also exhibit high anisotropic magnetic properties with a wasp-waist hysteresis loop and a bias shift of coercivity due to the shape anisotropy and the exchange coupling between the core and the thin oxidized surface layer.

  1. Evaluation of the performance degradation at PAFC investigation of dealloying process of electrocatalysts with in-situ XRD

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Noriyuki; Uchida, Hiroyuki; Watanabe, Masahiro [Yamanashi Univ., Kofu (Japan)] [and others

    1996-12-31

    As a complementary research project to the demonstration project of 5MW and 1 MW PAFC plants, the mechanism and rate of deterioration of the cells and stacks have been studied from 1995 FY, with the objective of establishing an estimation method for the service life-time of the cell stacks. This work has been performed in the Basic Research Project, as part of that project on PAFC`s, selecting four subjects (Electrocatalysts degradation, Electrolyte fill-level, Cell material corrosion, Electrolyte loss) as the essential factors relating to the life-time. In this study, the effect of temperature and potential on the dealloying process of electrocatalysts was examined in H{sub 3}PO{sub 4} electrolyte with X-ray diffraction measurement.

  2. Single-ended mid-infrared laser-absorption sensor for simultaneous in situ measurements of Hsub>2sub>O, COsub>2sub>, CO, and temperature in combustion flows.

    Science.gov (United States)

    Peng, Wen Yu; Goldenstein, Christopher S; Mitchell Spearrin, R; Jeffries, Jay B; Hanson, Ronald K

    2016-11-20

    The development and demonstration of a four-color single-ended mid-infrared tunable laser-absorption sensor for simultaneous measurements of Hsub>2sub>O, COsub>2sub>, CO, and temperature in combustion flows is described. This sensor operates by transmitting laser light through a single optical port and measuring the backscattered radiation from within the combustion device. Scanned-wavelength-modulation spectroscopy with second-harmonic detection and first-harmonic normalization (scanned-WMS-2f/1f) was used to account for variable signal collection and nonabsorption losses in the harsh environment. Two tunable diode lasers operating near 2551 and 2482 nm were utilized to measure Hsub>2sub>O concentration and temperature, while an interband cascade laser near 4176 nm and a quantum cascade laser near 4865 nm were used for measuring COsub>2sub> and CO, respectively. The lasers were modulated at either 90 or 112 kHz and scanned across the peaks of their respective absorption features at 1 kHz, leading to a measurement rate of 2 kHz. A hybrid demultiplexing strategy involving both spectral filtering and frequency-domain demodulation was used to decouple the backscattered radiation into its constituent signals. Demonstration measurements were made in the exhaust of a laboratory-scale laminar methane-air flat-flame burner at atmospheric pressure and equivalence ratios ranging from 0.7 to 1.2. A stainless steel reflective plate was placed 0.78 cm away from the sensor head within the combustion exhaust, leading to a total absorption path length of 1.56 cm. Detection limits of 1.4% Hsub>2sub>O, 0.6% COsub>2sub>, and 0.4% CO by mole were reported. To the best of the authors' knowledge, this work represents the first demonstration of a mid-infrared laser-absorption sensor using a single-ended architecture in combustion flows.

  3. Evaluation of a sequential extraction process used for determining mercury binding mechanisms to coal combustion byproducts.

    Science.gov (United States)

    Noel, James D; Biswas, Pratim; Giammar, Daniel E

    2007-07-01

    Leaching of mercury from coal combustion byproducts is a concern because of the toxicity of mercury. Leachability of mercury can be assessed by using sequential extraction procedures. Sequential extraction procedures are commonly used to determine the speciation and mobility of trace metals in solid samples and are designed to differentiate among metals bound by different mechanisms and to different solid phases. This study evaluated the selectivity and effectiveness of a sequential extraction process used to determine mercury binding mechanisms to various materials. A six-step sequential extraction process was applied to laboratory-synthesized materials with known mercury concentrations and binding mechanisms. These materials were calcite, hematite, goethite, and titanium dioxide. Fly ash from a full-scale power plant was also investigated. The concentrations of mercury were measured using inductively coupled plasma (ICP) mass spectrometry, whereas the major elements were measured by ICP atomic emission spectrometry. The materials were characterized by X-ray powder diffraction and scanning electron microscopy with energy dispersive spectroscopy. The sequential extraction procedure provided information about the solid phases with which mercury was associated in the solid sample. The procedure effectively extracted mercury from the target phases. The procedure was generally selective in extracting mercury. However, some steps in the procedure extracted mercury from nontarget phases, and others resulted in mercury redistribution. Iron from hematite and goethite was only leached in the reducible and residual extraction steps. Some mercury associated with goethite was extracted in the ion exchangeable step, whereas mercury associated with hematite was extracted almost entirely in the residual step. Calcium in calcite and mercury associated with calcite were primarily removed in the acid-soluble extraction step. Titanium in titanium dioxide and mercury adsorbed onto

  4. Nonlinear optical and multiphoton processes for in situ manipulation and conversion of photons: applications to energy and healthcare (Conference Presentation)

    Science.gov (United States)

    Prasad, Paras N.

    2017-02-01

    Chiral control of nonlinear optical functions holds a great promise for a wide range of applications including optical signal processing, bio-sensing and chiral bio-imaging. In chiral polyfluorene thin films, we demonstrated extremely large chiral nonlinearity. The physics of manipulating excitation dynamics for photon transformation will be discussed, along with nanochemistry control of upconversion in hierarchically built organic chromophore coupled-core-multiple shell nanostructures which enable introduce new, organic-inorganic energy transfer routes for broadband light harvesting and increased upconversion efficiency via multistep cascaded energy transfer. We are pursuing the applications of photon conversion technology in IR harvesting for photovoltaics, high contrast bioimaging, photoacoustic imaging, photodynamic therapy, and optogenetics. An important application is in Brain research and Neurophotonics for functional mapping and modulation of brain activities. Another new direction pursued is magnetic field control of light in in a chiral polymer nanocomposite to achieve large magneto-optic coefficient which can enable sensing of extremely weak magnetic field due to brain waves. Finally, we will consider the thought provoking concept of utilizing photons to quantify, through magneto-optics, and augment - through nanoptogenetics, the cognitive states, thus paving the path way to a quantified human paradigm.

  5. Kinetics of transformation in an in-situ aluminum-strontium deformation processed metal-metal composite

    Science.gov (United States)

    Frerichs, Andrew Elliott

    2011-12-01

    Efficient electricity transmission is a key component in all plans to increase the amount of renewable power used in the decades ahead. Prime solar and wind generation sites are usually distant from major population centers, resulting in the need for improved conductor wires that are stronger, lighter, and have better conductivity than conventional conductors. Deformation processed metal-metal composites (DMMCs) have a desirable combination of high strength and good conductivity. One such DMMC, aluminum-strontium, was investigated in this study. The composite wire was created by extrusion, swaging, and wire drawing of bundled Al and Sr wires. Intermetallic compound formation between Al and Sr is of particular interest to produce a strong, conductive wire with good high-temperature strength. Samples of swaged and drawn Al-Sr composite wire were heat treated at 483K, 513K, 543K and 573K to produce samples at varying stages of intermetallic compound formation. Resistivity measurements were taken from samples over a range of heat treatment times and temperatures to calculate the activation energy for Al-Sr intermetallic compound formation. Scanning electron microscopy, differential scanning calorimetry, and x-ray diffraction were used to investigate the changes in the microstructure occurring in the samples as a function of heat treatment. In addition, mechanical properties data were generated for pure Sr metal.

  6. In situ heating SEM observation of the bainitic transformation process in Cu-17Al-11Mn (at.%) alloys.

    Science.gov (United States)

    Motomura, Shunichi; Soejima, Yohei; Miyoshi, Takayuki; Hara, Toru; Omori, Toshihiro; Kainuma, Ryosuke; Nishida, Minoru

    2016-04-01

    To understand the bainitic transformation behavior in Cu-17Al-11Mn (at.%) alloys, dynamicin situobservation during heating was carried out in a scanning electron microscope (SEM). In this study, after optimizing the sample preparation method and observation conditions, we successfully observed the transformation process with sufficient resolution and contrast. From the observation results, bainite is first formed preferentially at the grain boundaries of the parent phase. Bainite is also formed inside the grains to relax the elastic strain generated by the initial bainite. Regarding the growth mode, in the early stage of the transformation, bainite grows along the longitudinal direction, and in the late stage, it grows along the lateral direction. The growth rate of the bainite was also evaluated by continuous observation of the same plate. Dynamicin situobservation of a martensitic transformation in the same alloy was also performed to compare the growth mode with that of bainite, and it was found that the behavior is considerably different between bainitic and the martensitic transformations. © The Author 2015. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. A new combined nuclear magnetic resonance and Raman spectroscopic probe applied to in situ investigations of catalysts and catalytic processes

    Energy Technology Data Exchange (ETDEWEB)

    Camp, Jules C. J.; Mantle, Michael D. [Department of Chemical Engineering and Biotechnology, University of Cambridge, Pembroke Street, Cambridge CB2 3RA (United Kingdom); York, Andrew P. E. [Johnson Matthey Technology Centre, Blounts Court, Sonning Common, Reading RG4 9NH (United Kingdom); McGregor, James, E-mail: james.mcgregor@sheffield.ac.uk [Department of Chemical and Biological Engineering, University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom)

    2014-06-15

    Both Raman and nuclear magnetic resonance (NMR) spectroscopies are valuable analytical techniques capable of providing mechanistic information and thereby providing insights into chemical processes, including catalytic reactions. Since both techniques are chemically sensitive, they yield not only structural information but also quantitative analysis. In this work, for the first time, the combination of the two techniques in a single experimental apparatus is reported. This entailed the design of a new experimental probe capable of recording simultaneous measurements on the same sample and/or system of interest. The individual datasets acquired by each spectroscopic method are compared to their unmodified, stand-alone equivalents on a single sample as a means to benchmark this novel piece of equipment. The application towards monitoring reaction progress is demonstrated through the evolution of the homogeneous catalysed metathesis of 1‑hexene, with both experimental techniques able to detect reactant consumption and product evolution. This is extended by inclusion of magic angle spinning (MAS) NMR capabilities with a custom made MAS 7 mm rotor capable of spinning speeds up to 1600 Hz, quantified by analysis of the spinning sidebands of a sample of KBr. The value of this is demonstrated through an application involving heterogeneous catalysis, namely the metathesis of 2-pentene and ethene. This provides the added benefit of being able to monitor both the reaction progress (by NMR spectroscopy) and also the structure of the catalyst (by Raman spectroscopy) on the very same sample, facilitating the development of structure-performance relationships.

  8. Turbulent combustion

    Energy Technology Data Exchange (ETDEWEB)

    Talbot, L.; Cheng, R.K. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    Turbulent combustion is the dominant process in heat and power generating systems. Its most significant aspect is to enhance the burning rate and volumetric power density. Turbulent mixing, however, also influences the chemical rates and has a direct effect on the formation of pollutants, flame ignition and extinction. Therefore, research and development of modern combustion systems for power generation, waste incineration and material synthesis must rely on a fundamental understanding of the physical effect of turbulence on combustion to develop theoretical models that can be used as design tools. The overall objective of this program is to investigate, primarily experimentally, the interaction and coupling between turbulence and combustion. These processes are complex and are characterized by scalar and velocity fluctuations with time and length scales spanning several orders of magnitude. They are also influenced by the so-called {open_quotes}field{close_quotes} effects associated with the characteristics of the flow and burner geometries. The authors` approach is to gain a fundamental understanding by investigating idealized laboratory flames. Laboratory flames are amenable to detailed interrogation by laser diagnostics and their flow geometries are chosen to simplify numerical modeling and simulations and to facilitate comparison between experiments and theory.

  9. Tracking nitrous oxide emission processes at a suburban site with semicontinuous, in situ measurements of isotopic composition

    Science.gov (United States)

    Harris, Eliza; Henne, Stephan; Hüglin, Christoph; Zellweger, Christoph; Tuzson, Béla; Ibraim, Erkan; Emmenegger, Lukas; Mohn, Joachim

    2017-02-01

    The isotopic composition of atmospheric nitrous oxide (N2O) was measured semicontinuously, at ˜35 min frequency in intermittent periods of 1-6 days over one and a half years, using preconcentration coupled to a quantum cascade laser spectrometer at the suburban site of Dübendorf, Switzerland. The achieved measurement repeatability was 0.08‰, 0.11‰, and 0.10‰ for δ18O, site preference, and δ15Nbulk respectively, which is better than or equal to standard flask sampling-based isotope ratio mass spectrometry performance. The observed mean diurnal cycle reflected the buildup of N2O from isotopically light sources on an isotopically heavy tropospheric background. The measurements were used to determine the source isotopic composition, which varied significantly compared to chemical and meteorological parameters monitored at the site. FLEXPART-COSMO transport modeling in combination with modified Emissions Database for Global Atmospheric Research inventory emissions was used to model N2O mole fractions at the site. Additionally, isotopic signatures were estimated for different source categories using literature data and used to simulate N2O isotopic composition over the measurement period. The model was able to capture variability in N2O mole fraction well, but simulations of isotopic composition showed little agreement with observations. In particular, measured source isotopic composition exhibited one magnitude larger variability than simulated, clearly indicating that the range of isotopic source signatures estimated from literature significantly underestimates true variability of source signatures. Source δ18O signature was found to be the most sensitive tracer for urban/industry versus agricultural N2O. δ15Nbulk and site preference may provide more insight into microbial and chemical emission processes than partitioning of anthropogenic source categories.

  10. Effects of laser processing parameters on solidification microstructures of ternary Al_2O_3/YAG/ZrO_2 eutectic in situ composite and its thermal property

    Institute of Scientific and Technical Information of China (English)

    SU Hai-jun; ZHANG Jun; LIU Lin; FU Heng-zhi

    2009-01-01

    Rapid surface resolidification with a high powered CO_2-laser was performed in preparing directionally solidified Al_2O_3/YAG/ZrO_2 ternary eutectic ceramic in situ composite.The effects of laser processing parameters on the solidification microstructure characteristics and thermal properties were studied by scanning electron microscopy (SEM),energy dispersive spectroscopy (EDS),X-ray diffractometry (XRD) and synthetically thermal analysis (STA).Detailed investigations of the influence of laser power and scanning rate on the preparation and microstructural parameters of the ternary eutectic were presented.Moreover,the eutectic phase separation rule at high temperature was discussed.The results indicate that solidification microstructure of the ternary eutectic composite is greatly influenced by the laser processing parameters.The synthetically thermal analysis shows that the eutectic temperature of ternary Al_2O_3/YAG/ZrO_2 composite is 1 738 ℃,well matching the phase diagram of Al_2O_3-Y_2O_3-ZrO_2.

  11. Microbial production of propionic acid with Propionibacterium freudenreichii using an anion exchanger-based in situ product recovery (ISPR) process with direct and indirect contact of cells.

    Science.gov (United States)

    Wang, Peng; Wang, Yunshan; Su, Zhiguo

    2012-02-01

    The recovery of an inhibiting product from a bioreactor soon after its formation is an important issue in industrial bioprocess development. In the present study, the potential of the anion exchanger-based in situ product recovery (ISPR) technique for the biocatalytic production of propionic acid was discussed. The focus of the current work was the selection of a suitable configuration of metabolically active cells for application in propionic acid production. Accumulation of propionic acid in fermentation broth caused feedback inhibition of the growth and biotransformation activity of Propionibacterium freudenreichii CICC 10019. Relevant product inhibition kinetics was discussed, and the results showed that keeping the aqueous propionic acid concentration below 10.02 g L⁻¹ was an essential prerequisite for ISPR process. A batch study, in which three ISPR configuration mode designs were compared, was conducted. The comparison indicated that employing an external direct mode had significant advantages over other modes in terms of increased productivity and product yield, with a corresponding decrease in the number of downstream processing steps, as well as in substrate consumption. The fed-batch culture using an external direct mode for the continuous accumulation of propionic acid resulted in a cumulative propionic acid concentration of 62.5 g L⁻¹, with a corresponding product yield of 0.78 g propionic acid/g glucose.

  12. Effects of Q&P Processing Conditions on Austenite Carbon Enrichment Studied by In Situ High-Energy X-ray Diffraction Experiments

    Directory of Open Access Journals (Sweden)

    Sébastien Yves Pierre Allain

    2017-06-01

    Full Text Available We report the first ultra-fast time-resolved quantitative information on the quenching and partitioning process of conventional high-strength steel by an in situ high-energy X-ray diffraction (HEXRD experiment. The time and temperature evolutions of phase fractions, their carbon content, and internal stresses were determined and discussed for different process parameters. It is shown that the austenite-to-martensite transformation below the martensite start temperature Ms is followed by a stage of fast carbon enrichment in austenite during isothermal holding at both 400 and 450 °C. The analysis proposed supports the concurrent bainite transformation and carbon diffusion from martensite to austenite as the main mechanisms of this enrichment. Furthermore, we give evidence that high hydrostatic tensile stresses in austenite are produced during the final quenching, and must be taken into account for the estimation of the carbon content in austenite. Finally, a large amount of carbon is shown to be trapped in the microstructure.

  13. The use of an electric field as a processing parameter in the combustion synthesis of ceramics and composites

    Energy Technology Data Exchange (ETDEWEB)

    Munir, Z.A. [Univ. of California, Davis, CA (United States). Dept. of Chemical Engineering and Materials Science

    1995-08-01

    The use of electric field to activate the process of self-propagating high-temperature (SHS) is demonstrated. Experimental observations show that for several systems, combustion synthesis is only possible with the presence of a field. Modeling studies on the synthesis of {beta}-SiC have shown the effect of field is localized in the combustion zone and that the magnitude of this effect is related to {delta}E{sup 2} where {delta} is the electric conductivity and E is the field. The modeling studies showed a linear dependence between the combustion wave velocity and the applied voltage. Experimental results show a similar relationship between velocity and voltage with a dependence on the initial relative density of the reactant compacts. Investigations on the mechanism in field-activated synthesis were also made. The results confirm a model in which the rate of heat release from the field in the combustion zone is enhanced by the presence of a molten phase, Si in the case of synthesis of silicon carbide. The effect of field on the SHS reactions was also investigated for the synthesis of composite materials. Composites of MoSi{sub 2}-SiC, MoSi{sub 2}-ZrO{sub 2}, MoSi{sub 2}-Nb and B{sub 4}C-TiB{sub 2} were formed by field-activated combustion synthesis. In the case of MoSi{sub 2}-SiC, composites with molar ratios of SiC/MoSi{sub 2}(=x) ranging from zero to one have been prepared by this method. In the absence of a field no SHS reaction is possible for x > 0. Similarly, in the case of B{sub 4}C-TiB{sub 2}, composites with B{sub 4}C/TiB{sub 2}(=y) ratios of one or larger can only be synthesized in the SHS mode in the presence of a field.

  14. A Conceptual Model of Coupled Biogeochemical and Hydrogeological Processes Affected by In Situ Cr(VI) Bioreduction in Groundwater at Hanford 100H Site

    Science.gov (United States)

    Faybishenko, B.; Long, P. E.; Hazen, T. C.; Hubbard, S. S.; Williams, K. H.; Peterson, J. E.; Chen, J.; Volkova, E. V.; Newcomer, D. R.; Resch, C. T.; Cantrell, K.; Conrad, M. S.; Brodie, E. L.; Joyner, D. C.; Borglin, S. E.; Chakraborty, R. C.

    2007-05-01

    The overall objective of this presentation is to demonstrate a conceptual multiscale, multidomain model of coupling of biogeochemical and hydrogeological processes during bioremediation of Cr(VI) contaminated groundwater at Hanford 100H site. A slow release polylactate, Hydrogen Release Compound (HRCTM), was injected in Hanford sediments to stimulate immobilization of Cr(VI). The HRC injection induced a 2-order-of- magnitude increase in biomass and the onset of reducing biogeochemical conditions [e.g., redox potential decreased from +240 to -130 mV and dissolved oxygen (DO) was completely removed]. A three-well system, comprised of an injection well and upgradient and downgradient monitoring wells, was used for conducting the in situ biostimulation, one regional flow (no-pumping) tracer test, and five pumping tests along with the Br-tracer injection. Field measurements were conducted using a Br ion-selective electrode and a multiparameter flow cell to collect hourly data on temperature, pH, redox potential, electrical conductivity, and DO. Groundwater sampling was conducted by pumping through specially designed borehole water samplers. Cross-borehole radar tomography and seismic measurements were carried out to assess the site background lithological heterogeneity and the migration pathways of HRC byproducts through groundwater after the HRC injection. Several alternative approaches, including conventional and fractional advective dispersion equations and geostatistical analysis, were used to characterize hydraulic and biogeochemical transport parameters. The results of a joint inversion of cross-borehole geophysical tomography and flow-rate measurements in boreholes indicate the presence of a bimodal distribution of hydraulic conductivity for Hanford sediments. The Br- concentration double-peak BTCs curves indicate that HRC injection caused an increase in the tracer travel time (mainly in the low-permeability zone) over the period of observations of about 2 years

  15. In-situ X-Ray Analysis of Rapid Thermal Processing for Thin-Film Solar Cells: Closing the Gap between Production and Laboratory Efficiency