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Sample records for chemical-looping combustion system

  1. Chemical Looping Combustion Reactions and Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sarofim, Adel; Lighty, JoAnn; Smith, Philip; Whitty, Kevin; Eyring, Edward; Sahir, Asad; Alvarez, Milo; Hradisky, Michael; Clayton, Chris; Konya, Gabor; Baracki, Richard; Kelly, Kerry

    2011-07-01

    Chemical Looping Combustion (CLC) is one promising fuel-combustion technology, which can facilitate economic CO2 capture in coal-fired power plants. It employs the oxidation/reduction characteristics of a metal, or oxygen carrier, and its oxide, the oxidizing gas (typically air) and the fuel source may be kept separate. This work focused on two classes of oxygen carrier, one that merely undergoes a change in oxidation state, such as Fe3O4/Fe2O3 and one that is converted from its higher to its lower oxidation state by the release of oxygen on heating, i.e., CuO/Cu2O. This topical report discusses the results of four complementary efforts: (1) the development of process and economic models to optimize important design considerations, such as oxygen carrier circulation rate, temperature, residence time; (2) the development of high-performance simulation capabilities for fluidized beds and the collection, parameter identification, and preliminary verification/uncertainty quantification (3) the exploration of operating characteristics in the laboratory-scale bubbling bed reactor, with a focus on the oxygen carrier performance, including reactivity, oxygen carrying capacity, attrition resistance, resistance to deactivation, cost and availability (4) the identification of mechanisms and rates for the copper, cuprous oxide, and cupric oxide system using thermogravimetric analysis.

  2. Chemical Looping Combustion Reactions and Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sarofim, Adel; Lighty, JoAnn; Smith, Philip; Whitty, Kevin; Eyring, Edward; Sahir, Asad; Alvarez, Milo; Hradisky, Michael; Clayton, Chris; Konya, Gabor; Baracki, Richard; Kelly, Kerry

    2014-03-01

    Chemical Looping Combustion (CLC) is one promising fuel-combustion technology, which can facilitate economic CO{sub 2} capture in coal-fired power plants. It employs the oxidation/reduction characteristics of a metal, or oxygen carrier, and its oxide, the oxidizing gas (typically air) and the fuel source may be kept separate. This topical report discusses the results of four complementary efforts: (5.1) the development of process and economic models to optimize important design considerations, such as oxygen carrier circulation rate, temperature, residence time; (5.2) the development of high-performance simulation capabilities for fluidized beds and the collection, parameter identification, and preliminary verification/uncertainty quantification; (5.3) the exploration of operating characteristics in the laboratoryscale bubbling bed reactor, with a focus on the oxygen carrier performance, including reactivity, oxygen carrying capacity, attrition resistance, resistance to deactivation, cost and availability; and (5.4) the identification of kinetic data for copper-based oxygen carriers as well as the development and analysis of supported copper oxygen carrier material. Subtask 5.1 focused on the development of kinetic expressions for the Chemical Looping with Oxygen Uncoupling (CLOU) process and validating them with reported literature data. The kinetic expressions were incorporated into a process model for determination of reactor size and oxygen carrier circulation for the CLOU process using ASPEN PLUS. An ASPEN PLUS process model was also developed using literature data for the CLC process employing an iron-based oxygen carrier, and the results of the process model have been utilized to perform a relative economic comparison. In Subtask 5.2, the investigators studied the trade-off between modeling approaches and available simulations tools. They quantified uncertainty in the high-performance computing (HPC) simulation tools for CLC bed applications. Furthermore

  3. Attrition Rate of Oxygen Carriers in Chemical Looping Combustion Systems

    Science.gov (United States)

    Feilen, Harry Martin

    This project developed an evaluation methodology for determining, accurately and rapidly, the attrition resistance of oxygen carrier materials used in chemical looping technologies. Existing test protocols, to evaluate attrition resistance of granular materials, are conducted under non-reactive and ambient temperature conditions. They do not accurately reflect the actual behavior under the unique process conditions of chemical looping, including high temperatures and cyclic operation between oxidizing and reducing atmospheres. This project developed a test method and equipment that represented a significant improvement over existing protocols. Experimental results obtained from this project have shown that hematite exhibits different modes of attrition, including both due to mechanical stresses and due to structural changes in the particles due to chemical reaction at high temperature. The test methodology has also proven effective in providing reactivity changes of the material with continued use, a property, which in addition to attrition, determines material life. Consumption/replacement cost due to attrition or loss of reactivity is a critical factor in the economic application of the chemical looping technology. This test method will allow rapid evaluation of a wide range of materials that are best suited for this technology. The most important anticipated public benefit of this project is the acceleration of the development of chemical looping technology for lowering greenhouse gas emissions from fossil fuel combustion.

  4. A solar assisted polygeneration system integrating methane reforming and chemical looping combustion with zero carbon emission

    National Research Council Canada - National Science Library

    WANG, Jiangjiang; FU, Chao

    2017-01-01

    .... This paper combines chemical-looping combustion (CLC) and methane reforming with CO2 to accomplish CO2 capture and utilization and proposes a novel polygeneration system to produce syngas, electricity, chilled water for cooling, and hot water...

  5. A Polygeneration System Based on Multi-Input Chemical Looping Combustion

    Directory of Open Access Journals (Sweden)

    Xiaosong Zhang

    2014-11-01

    Full Text Available This paper proposes a polygeneration system based on a multi-input chemical looping combustion system, which generates methanol and electricity, through the use of natural gas and coal. In this system, the chemical looping hydrogen (CLH production system and the coal-based methanol production system are integrated. A high quality fuel, natural gas, is used to improve the conversion ratio of coal. The Gibbs energy of the two kinds of fuels is fully used. Benefitting from the chemical looping process, 27% CO2 can be captured without energy penalty. With the same outputs of methanol and electricity, the energy savings ratio of the new system is about 12%. Based on the exergy analyses, it is disclosed that the integration of synthetic utilization of natural gas and coal plays a significant role in reducing the exergy destruction of the new system. The promising results obtained in this paper may lead to a clean coal technology that will utilize natural gas and coal more efficiently and economically.

  6. Study of highly efficient power generation system based on chemical-looping combustion; Chemical loop nenshoho ni yoru kokoritsu hatsuden system no kaihatsu ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, S.; Suzuki, T.; Yamamoto, M. [Tokyo Institute of Technology, Tokyo (Japan). Research Laboratory of Resources Utilization

    1997-02-01

    This paper describes the research and development of power generation system by means of chemical-looping combustion. For this system, fuel flows in a reduction reactor and air flows in an oxidation reactor. These two flows are separated. As a result, recovery of CO2 without energy consumption, drastic improvement of power generation efficiency, and suppression of NOx emission are expected. To realize the above, two promising candidates, NiCoO2/YSZ and NiO2/NiAl2O4, have been found as recycle solid particles between the both reactors. These have excellent oxidation/reduction cycle characteristics. By these particles as well as the existing particle, NiO/YSZ, practical application of the chemical-looping combustion is realized. Besides LNG, coal and hydrogen were considered as fuels. When using coal or hydrogen, it was found that temperature of the reduction reactor should be increased the same as that of the oxidation reactor. This is a different point from a case using LNG as a fuel. 5 refs., 2 figs.

  7. Operation of fixed-bed chemical looping combustion

    NARCIS (Netherlands)

    Kimball, E.; Hamers, H.P.; Cobden, P.D.; Gallucci, F.; Sint Annaland, M. van

    2013-01-01

    Chemical Looping Combustion is an alternative technology for CO2 capture. While most systems utilize dual circulating fluidized-beds, this work shows that fixed-bed Chemical Looping Combustion is a feasible configuration for this technology. The inherent separation of the CO2 from the depleted air

  8. Simulation of mass and energy balances of a chemical-looping combustion system

    Energy Technology Data Exchange (ETDEWEB)

    B. Kronberger; G. Loeffler; H. Hofbauer [Vienna University of Technology, Vienna (Austria). Institute of Chemical Engineering

    2003-07-01

    Chemical-Looping Combustion is constructed from two separate reactors: i) the fuel reactor where the fuel gas is oxidised and ii) the air reactor where the metal oxide re-oxidation reaction takes place. The oxygen transfer is realised by means of oxygen carrier materials, and the oxidation products of the fuel are kept separated from the combustion air. No extra energy for CO{sub 2} separation and further sequestration is needed. A mathematical model of a CLC system with an integrated solution of the mass and energy balances was set up. Evaluation of the effect of numerous design and operating parameters, such as fuel gas composition and reactor cooling arrangement that depend on the oxygen carrier type, were carried out. The results of the model reveal that in many cases additional reactor cooling and oxygen carrier flow have to be chosen properly to guarantee appropriate temperatures in the reactor and complete fuel gas combustion. These are requirements for avoiding thermal and mechanical decomposition of the oxygen carrier, and operation of the electricity generation cycle with high thermal and CO{sub 2}-capture efficiency.

  9. Hybrid Combustion-Gasification Chemical Looping

    Energy Technology Data Exchange (ETDEWEB)

    Herbert Andrus; Gregory Burns; John Chiu; Gregory Lijedahl; Peter Stromberg; Paul Thibeault

    2009-01-07

    For the past several years Alstom Power Inc. (Alstom), a leading world-wide power system manufacturer and supplier, has been in the initial stages of developing an entirely new, ultra-clean, low cost, high efficiency power plant for the global power market. This new power plant concept is based on a hybrid combustion-gasification process utilizing high temperature chemical and thermal looping technology The process consists of the oxidation, reduction, carbonation, and calcination of calcium-based compounds, which chemically react with coal, biomass, or opportunity fuels in two chemical loops and one thermal loop. The chemical and thermal looping technology can be alternatively configured as (i) a combustion-based steam power plant with CO{sub 2} capture, (ii) a hybrid combustion-gasification process producing a syngas for gas turbines or fuel cells, or (iii) an integrated hybrid combustion-gasification process producing hydrogen for gas turbines, fuel cells or other hydrogen based applications while also producing a separate stream of CO{sub 2} for use or sequestration. In its most advanced configuration, this new concept offers the promise to become the technology link from today's Rankine cycle steam power plants to tomorrow's advanced energy plants. The objective of this work is to develop and verify the high temperature chemical and thermal looping process concept at a small-scale pilot facility in order to enable AL to design, construct and demonstrate a pre-commercial, prototype version of this advanced system. In support of this objective, Alstom and DOE started a multi-year program, under this contract. Before the contract started, in a preliminary phase (Phase 0) Alstom funded and built the required small-scale pilot facility (Process Development Unit, PDU) at its Power Plant Laboratories in Windsor, Connecticut. Construction was completed in calendar year 2003. The objective for Phase I was to develop the indirect combustion loop with CO{sub 2

  10. Density functional theory study on activity of α-Fe 2O 3 in chemical-looping combustion system

    Science.gov (United States)

    Dong, Changqing; Sheng, Shuhui; Qin, Wu; Lu, Qiang; Zhao, Ying; Wang, Xiaoqiang; Zhang, Junjiao

    2011-08-01

    The dominant growth planes (0 0 0 1) and (1 1 0 2) have been used to investigate the activity of the natural α-Fe 2O 3 in chemical-looping combustion system based on density functional theory (DFT) calculations. In the chemical-looping combustion system, CO is selected as the probe fuel gas to detect the activities of the different surfaces. CO interacts stronger to Fe 2O 3 (1 1 0 2) than Fe 2O 3 (0 0 0 1). CO can be oxidized into CO 2 species directly on Fe 2O 3 (1 1 0 2) rather than Fe 2O 3 (0 0 0 1). The formation of CO 2 accompanying with a transformation from hematite to magnetite acted as the key step for the reduction process of hematite.

  11. Chemical Looping Combustion of Rice Husk

    OpenAIRE

    Rashmeet Singh Monga; Ganesh R. Kale

    2015-01-01

    A thermodynamic investigation of direct chemical looping combustion (CLC) of rice husk is presented in this paper. Both steam and CO2 are used for gasification within the temperature range of 500–1200˚C and different amounts of oxygen carriers. Chemical equilibrium model was considered for the CLC fuel reactor. The trends in product compositions of the fuel reactor, were determined. Rice husk gasification using 3 moles H2O and 0 moles CO2 per mole carbon (in rice husk) at 1 bar pr...

  12. Scale-up of fixed-bed chemical looping combustion

    NARCIS (Netherlands)

    Kimball, E.; Geerdink, P.; Goetheer, E.L.V.

    2011-01-01

    Fixed-bed chemical looping combustion is currently being studied experimentally with the optimization of systems up to 1 kW. One of the key advantages for using the fixed-bed configuration over fluidized-beds is the flexibility in operating parameters that allows for application of CLC not only to

  13. Advancements in Development of Chemical-Looping Combustion: A Review

    Directory of Open Access Journals (Sweden)

    He Fang

    2009-01-01

    Full Text Available Chemical-looping combustion (CLC is a novel combustion technology with inherent separation of greenhouse CO2. Extensive research has been performed on CLC in the last decade with respect to oxygen carrier development, reaction kinetics, reactor design, system efficiencies, and prototype testing. Transition metal oxides, such as Ni, Fe, Cu, and Mn oxides, were reported as reactive species in the oxygen carrier particles. Ni-based oxygen carriers exhibited the best reactivity and stability during multiredox cycles. The performance of the oxygen carriers can be improved by changing preparation method or by making mixedoxides. The CLC has been demonstrated successfully in continuously operated prototype reactors based on interconnected fluidized-bed system in the size range of 0.3–50 kW. High fuel conversion rates and almost 100%  CO2 capture efficiencies were obtained. The CLC system with two interconnected fluidized-bed reactors was considered the most suitable reactor design. Development of oxygen carriers with excellent reactivity and stability is still one of the challenges for CLC in the near future. Experiences of building and operating the large-scale CLC systems are needed before this technology is used commercially. Chemical-looping reforming (CLR and chemical-looping hydrogen (CLH are novel chemical-looping techniques to produce synthesis gas and hydrogen deserving more attention and research.

  14. Chemical Looping Combustion of Methane: A Technology Development View

    Directory of Open Access Journals (Sweden)

    Rutuja Bhoje

    2013-01-01

    Full Text Available Methane is a reliable and an abundantly available energy source occurring in nature as natural gas, biogas, landfill gas, and so forth. Clean energy generation using methane can be accomplished by using chemical looping combustion. This theoretical study for chemical looping combustion of methane was done to consider some key technology development points to help the process engineer choose the right oxygen carrier and process conditions. Combined maximum product (H2O + CO2 generation, weight of the oxygen carrier, net enthalpy of CLC process, byproduct formation, CO2 emission from the air reactor, and net energy obtainable per unit weight (gram of oxygen carrier in chemical looping combustion can be important parameters for CLC operation. Carbon formed in the fuel reactor was oxidised in the air reactor and that increased the net energy obtainable from the CLC process but resulted in CO2 emission from the air reactor. Use of CaSO4 as oxygen carrier generated maximum energy (−5.3657 kJ, 800°C per gram of oxygen carrier used in the CLC process and was found to be the best oxygen carrier for methane CLC. Such a model study can be useful to identify the potential oxygen carriers for different fuel CLC systems.

  15. Chemical Looping Combustion of Methane: A Technology Development View

    OpenAIRE

    Rutuja Bhoje; Ganesh R. Kale; Nitin Labhsetwar; Sonali Borkhade

    2013-01-01

    Methane is a reliable and an abundantly available energy source occurring in nature as natural gas, biogas, landfill gas, and so forth. Clean energy generation using methane can be accomplished by using chemical looping combustion. This theoretical study for chemical looping combustion of methane was done to consider some key technology development points to help the process engineer choose the right oxygen carrier and process conditions. Combined maximum product (H2O + CO2) generation, weigh...

  16. Operation of fixed-bed chemical looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Kimball, E. [TNO, Gas Treatment, Leeghwaterstraat 46, 2628 CA Delft (Netherlands); Hamers, H.P.; Gallucci, F.; Van Sint Annaland, M. [Technische Universiteit Eindhoven, Den Dolech 2, 5612 AZ Eindhoven (Netherlands); Cobden, P. [Energy research Center of the Netherlands, Westerduinweg 3, 1755 ZG Petten (Netherlands)

    2013-07-01

    Chemical Looping Combustion is an alternative technology for CO2 capture. While most systems utilize dual circulating fluidized-beds, this work shows that fixed-bed Chemical Looping Combustion is a feasible configuration for this technology. The inherent separation of the CO2 from the depleted air stream gives a very low efficiency penalty, which is further improved by the possibility of using a pressurized fixed-bed system, a factor much more difficult to realize with circulating fluidized beds. A laboratory scale experimental system has been constructed for the purpose of validating a numerical model. The results from the numerical model have agreed well with experimental data over full oxidation-reduction cycles and will be presented in subsequent publications. The work briefly described here, and to be presented in detail in coming publications, forms a basis which proves feasibility, but also opens up several possibilities for further investigations needed to scale-up and eventually commercialize CLC for power generation with inherent CO2 capture.

  17. Packed Bed Reactor Technology for Chemical-Looping Combustion

    NARCIS (Netherlands)

    Noorman, S.; van Sint Annaland, M.; Kuipers, J.A.M.

    2007-01-01

    Chemical-looping combustion (CLC) has emerged as an alternative for conventional power production processes to intrinsically integrate power production and CO2 capture. In this work a new reactor concept for CLC is proposed, based on dynamically operated packed bed reactors. With analytical

  18. Experimental validation of packed bed chemical-looping combustion

    NARCIS (Netherlands)

    Noorman, S.; van Sint Annaland, M.; Kuipers, J.A.M.

    2010-01-01

    Chemical-looping combustion has emerged as a promising alternative technology, intrinsically integrating CO2 capture in power production. A novel reactor concept based on dynamically operated packed beds has been proposed [Noorman, S., van Sint Annaland, M., Kuipers, J.A.M., 2007. Packed bed reactor

  19. Tri-metallic ferrite oxygen carriers for chemical looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Siriwardane, Ranjani V.; Fan, Yueying

    2017-10-25

    The disclosure provides a tri-metallic ferrite oxygen carrier for the chemical looping combustion of carbonaceous fuels. The tri-metallic ferrite oxygen carrier comprises Cu.sub.xFe.sub.yMn.sub.zO.sub.4-.delta., where Cu.sub.xFe.sub.yMn.sub.zO.sub.4-.delta. is a chemical composition. Generally, 0.5.ltoreq.x.ltoreq.2.0, 0.2.ltoreq.y.ltoreq.2.5, and 0.2.ltoreq.z.ltoreq.2.5, and in some embodiments, 0.8.ltoreq.x.ltoreq.1.2, y.ltoreq.1.2, and z.gtoreq.0.8. The tri-metallic ferrite oxygen carrier may be used in various applications for the combustion of carbonaceous fuels, including as an oxygen carrier for chemical looping combustion.

  20. Comparison of oxygen carriers for chemical-looping combustion

    Directory of Open Access Journals (Sweden)

    Johansson Marcus

    2006-01-01

    Full Text Available Chemical-looping combustion is a combustion technology with inherent separation of the greenhouse gas CO2. This technique involves combustion of fossil fuels by means of an oxygen carrier which transfers oxygen from the air to the fuel. In this manner a decrease in efficiency is avoided for the energy demanding separation of CO2 from the rest of the flue gases. Results from fifty oxygen carriers based on iron-, manganese- and nickel oxides on different inert materials are compared. The particles were prepared using freeze granulation, sintered at different temperatures and sieved to a size 125-180 mm. To simulate the environment the particles would be exposed to in a chemical-looping combustor, reactivity tests under alternating oxidizing and reducing conditions were performed in a laboratory fluidized bed-reactor of quartz. Reduction was performed in 50% CH4/50% H2O while the oxidation was carried out in 5% O2 in nitrogen. In general nickel particles are the most reactive, followed by manganese. Iron particles are harder but have a lower reactivity. An increase in sintering temperatures normally leads to an increase in strength and decrease in reactivity. Several particles investigated display a combination of high reactivity and strength as well as good fluidization behavior, and are feasible for use as oxygen carriers in chemical-looping combustion.

  1. Bimetallic Fe-Ni Oxygen Carriers for Chemical Looping Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Bhavsar, Saurabh; Veser, Goetz

    2013-11-06

    The relative abundance, low cost, and low toxicity of iron make Fe-based oxygen carriers of great interest for chemical looping combustion (CLC), an emerging technology for clean and efficient combustion of fossil and renewable fuels. However, Fe also shows much lower reactivity than other metals (such as Ni and Cu). Here, we demonstrate strong improvement of Fe-based carriers by alloying the metal phase with Ni. Through a combination of carrier synthesis and characterization with thermogravimetric and fixed-bed reactor studies, we demonstrate that the addition of Ni results in a significant enhancement in activity as well as an increase in selectivity for total oxidation. Furthermore, comparing alumina and ceria as support materials highlights the fact that reducible supports can result in a strong increase in oxygen carrier utilization.

  2. Natural Ores as Oxygen Carriers in Chemical Looping Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Hanjing; Siriwardane, Ranjani; Simonyi, Thomas; Poston, James

    2013-08-01

    Chemical looping combustion (CLC) is a combustion technology that utilizes oxygen from oxygen carriers (OC), such as metal oxides, instead of air to combust fuels. The use of natural minerals as oxygen carriers has advantages, such as lower cost and availability. Eight materials, based on copper or iron oxides, were selected for screening tests of CLC processes using coal and methane as fuels. Thermogravimetric experiments and bench-scale fixed-bed reactor tests were conducted to investigate the oxygen transfer capacity, reaction kinetics, and stability during cyclic reduction/oxidation reaction. Most natural minerals showed lower combustion capacity than pure CuO/Fe{sub 2}O{sub 3} due to low-concentrations of active oxide species in minerals. In coal CLC, chryscolla (Cu-based), magnetite, and limonite (Fe-based) demonstrated better reaction performances than other materials. The addition of steam improved the coal CLC performance when using natural ores because of the steam gasification of coal and the subsequent reaction of gaseous fuels with active oxide species in the natural ores. In methane CLC, chryscolla, hematite, and limonite demonstrated excellent reactivity and stability in 50-cycle thermogravimetric analysis tests. Fe{sub 2}O{sub 3}-based ores possess greater oxygen utilization but require an activation period before achieving full performance in methane CLC. Particle agglomeration issues associated with the application of natural ores in CLC processes were also studied by scanning electron microscopy (SEM).

  3. Chemical-Looping Combustion and Gasification of Coals and Oxygen Carrier Development: A Brief Review

    Directory of Open Access Journals (Sweden)

    Ping Wang

    2015-09-01

    Full Text Available Chemical-looping technology is one of the promising CO2 capture technologies. It generates a CO2 enriched flue gas, which will greatly benefit CO2 capture, utilization or sequestration. Both chemical-looping combustion (CLC and chemical-looping gasification (CLG have the potential to be used to generate power, chemicals, and liquid fuels. Chemical-looping is an oxygen transporting process using oxygen carriers. Recently, attention has focused on solid fuels such as coal. Coal chemical-looping reactions are more complicated than gaseous fuels due to coal properties (like mineral matter and the complex reaction pathways involving solid fuels. The mineral matter/ash and sulfur in coal may affect the activity of oxygen carriers. Oxygen carriers are the key issue in chemical-looping processes. Thermogravimetric analysis (TGA has been widely used for the development of oxygen carriers (e.g., oxide reactivity. Two proposed processes for the CLC of solid fuels are in-situ Gasification Chemical-Looping Combustion (iG-CLC and Chemical-Looping with Oxygen Uncoupling (CLOU. The objectives of this review are to discuss various chemical-looping processes with coal, summarize TGA applications in oxygen carrier development, and outline the major challenges associated with coal chemical-looping in iG-CLC and CLOU.

  4. CO{sub 2} capture from coal combustion using chemical-looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Tobias Mattisson; Francisco Garcia-Labiano; Bernhard Kronberger; Anders Lyngfelt; Juan Adanez; Hermann Hofbauer [Chalmers University of Technology, Goeteborg (Sweden). Department of Energy and Environment, Division of Energy Technology

    2006-07-01

    Chemical-looping combustion (CLC) is a combustion technology where an oxygen carrier is used to transfer oxygen from the combustion air to the fuel, thus avoiding direct contact between air and fuel. Thus, CO{sub 2} and H{sub 2}O are inherently separated from the rest of the flue gases, and no major energy is expended for this separation. The paper presents results from a three year project devoted to developing the CLC technology for use with syngas from coal combustion. The project has focused on i) the development of oxygen carrier particles, ii) establishing a reactor design and feasible operating conditions and iii) construction and operation of a continuously working hot reactor. Approximately 300 different oxygen carriers based on oxides of the metals Ni, Fe, Mn and Cu were investigated with respect to parameters which are important in a CLC system, and from these investigations, several particles were found to possess suitable qualities as oxygen carriers. Several cold-model prototypes of CLC based on interconnected fluidized beds were tested, and from these tests a hot prototype CLC reactor system was constructed and operated successfully using three carriers based on Ni, Fe and Mn developed within the project for 30-70 h. 8 refs., 5 figs.

  5. Chemical looping combustion. Fuel conversion with inherent CO2 capture

    Energy Technology Data Exchange (ETDEWEB)

    Brandvoll, Oeyvind

    2005-07-01

    Chemical looping combustion (CLC) is a new concept for fuel energy conversion with CO2 capture. In CLC, fuel combustion is split into separate reduction and oxidation processes, in which a solid carrier is reduced and oxidized, respectively. The carrier is continuously recirculated between the two vessels, and hence direct contact between air and fuel is avoided. As a result, a stoichiometric amount of oxygen is transferred to the fuel by a regenerable solid intermediate, and CLC is thus a variant of oxy-fuel combustion. In principle, pure CO2 can be obtained from the reduction exhaust by condensation of the produced water vapour. The thermodynamic potential and feasibility of CLC has been studied by means of process simulations and experimental studies of oxygen carriers. Process simulations have focused on parameter sensitivity studies of CLC implemented in 3 power cycles; CLC-Combined Cycle, CLC-Humid Air Turbine and CLC-Integrated Steam Generation. Simulations indicate that overall fuel conversion ratio, oxidation temperature and operating pressure are among the most important process parameters in CLC. A promising thermodynamic potential of CLC has been found, with efficiencies comparable to, - or better than existing technologies for CO2 capture. The proposed oxygen carrier nickel oxide on nickel spinel (NiONiAl) has been studied in reduction with hydrogen, methane and methane/steam as well as oxidation with dry air. It has been found that at atmospheric pressure and temperatures above 600 deg C, solid reduction with dry methane occurs with overall fuel conversion of 92%. Steam methane reforming is observed along with methane cracking as side reactions, yielding an overall selectivity of 90% with regard to solid reduction. If steam is added to the reactant fuel, coking can be avoided. A methodology for long-term investigation of solid chemical activity in a batch reactor is proposed. The method is based on time variables for oxidation. The results for Ni

  6. Control and optimization system and method for chemical looping processes

    Science.gov (United States)

    Lou, Xinsheng; Joshi, Abhinaya; Lei, Hao

    2015-02-17

    A control system for optimizing a chemical loop system includes one or more sensors for measuring one or more parameters in a chemical loop. The sensors are disposed on or in a conduit positioned in the chemical loop. The sensors generate one or more data signals representative of an amount of solids in the conduit. The control system includes a data acquisition system in communication with the sensors and a controller in communication with the data acquisition system. The data acquisition system receives the data signals and the controller generates the control signals. The controller is in communication with one or more valves positioned in the chemical loop. The valves are configured to regulate a flow of the solids through the chemical loop.

  7. CaMn0.875Ti0.125O3 as oxygen carrier for chemical-looping combustion with oxygen uncoupling (CLOU)—Experiments in a continuously operating fluidized-bed reactor system

    KAUST Repository

    Rydén, Magnus

    2011-03-01

    Particles of the perovskite material CaMn0.875Ti0.125O3 has been examined as oxygen carrier for chemical-looping with oxygen uncoupling, and for chemical-looping combustion of natural gas, by 70h of experiments in a circulating fluidized-bed reactor system. For the oxygen uncoupling experiments, it was found that the particles released O2 in gas phase at temperatures above 720°C when the fuel reactor was fluidized with CO2. The effect increased with increased temperature, and with the O2 partial pressure in the air reactor. At 950°C, the O2 concentration in the outlet from the fuel reactor was in the order of 4.0vol%, if the particles were oxidized in air. For the chemical-looping combustion experiments the combustion efficiency with standard process parameters was in the order of 95% at 950°C, using 1000kg oxygen carrier per MW natural gas, of which about 30% was located in the fuel reactor. Reducing the fuel flow so that 1900kg oxygen carrier per MW natural gas was used improved the combustion efficiency to roughly 99.8%. The particles retained their physical properties, reactivity with CH4 and ability to release gas-phase O2 reasonably well throughout the testing period and there were no problems with the fluidization or formation of solid carbon in the reactor. X-ray diffraction showed that the particles underwent changes in their phase composition though. © 2010 Elsevier Ltd.

  8. Design and scale-up of a combustion process for inherent CO{sub 2} separation by chemical looping combustion; Design und Scale-up eines Verbrennungsverfahrens zur inhaerenten CO{sub 2} - Abtrennung mittels Chemical-Looping Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Kronberger, B.; Luisser, M.; Loeffler, G.; Hofbauer, H. [Technische Universitaet Wien, Institut fuer Verfahrenstechnik, Umwelttechnik und Technische Biowissenschaften, Wien (Austria)

    2004-07-01

    Chemical looping combustion (CLC) is a novel power plant concept with inherent separation of carbon dioxide. Using metal oxides as oxygen carriers, oxygen is separated from the combustion air and is supplied to the fuel for oxidation. There is no direct contact between fuel and combustion air, and the combustion products CO2 and water are obtained separately from nitrogen. The contribution presents the state of development of the process. Design criteria are derived from the research findings so far in the fields of oxygen carrier reactivity and stability, fluid dynamics of the reactor system, simulation of power plant processes, and prototype operation. The design criteria, together with the scale-up criteria developed for CLC, provide the basis for developing a power plant concept with integrated CLC combustion. (orig.)

  9. Regenerable mixed copper-iron-inert support oxygen carriers for solid fuel chemical looping combustion process

    Energy Technology Data Exchange (ETDEWEB)

    Siriwardane, Ranjani V.; Tian, Hanjing

    2016-12-20

    The disclosure provides an oxygen carrier for a chemical looping cycle, such as the chemical looping combustion of solid carbonaceous fuels, such as coal, coke, coal and biomass char, and the like. The oxygen carrier is comprised of at least 24 weight % (wt %) CuO, at least 10 wt % Fe2O3, and an inert support, and is typically a calcine. The oxygen carrier exhibits a CuO crystalline structure and an absence of iron oxide crystalline structures under XRD crystallography, and provides an improved and sustained combustion reactivity in the temperature range of 600.degree. C.-1000.degree. C. particularly for solid fuels such as carbon and coal.

  10. Reactor choices for chemical looping combustion (CLC) dependencies on materials characteristics

    NARCIS (Netherlands)

    Kimball, E.; Lambert, A.; Fossdal, A.; Leenman, R.N.; Comte, E.; Bos, W.A.P. van den; Blom, R.

    2013-01-01

    The physio-chemical stability of the oxygen carrier material during chemical looping combustion (CLC) operation is crucial. In the present paper we discuss the challenges connected to operating a metal oxide base material in a cyclic manner between oxidizing and reducing atmospheres. Especially,

  11. Effects of operating pressure on the key parameters of coal direct chemical looping combustion

    National Research Council Canada - National Science Library

    Rahul Wadhwani Bikash Mohanty

    2016-01-01

    Techno-economic development of chemical looping combustion (CLC) process has been one of the most pursued research areas of the present decade due to its ability to reduce carbon foot print during utilization of coal to generate energy...

  12. A novel reactor configuration for packed bed chemical-looping combustion of syngas

    NARCIS (Netherlands)

    Hamers, H.P.; Gallucci, F.; Cobden, P.D.; Kimball, E.; Sint Annaland, M. van

    2013-01-01

    This study reports on the application of chemical looping combustion (CLC) in pressurized packed bed reactors using syngas as a fuel. High pressure operation of CLC in packed bed has a different set of challenges in terms of material properties, cycle and reactor design compared to fluidized bed

  13. Study of dimensional changes during redox cycling of oxygen carrier materials for chemical looping combustion

    NARCIS (Netherlands)

    Fossdal, A.; Darell, O.; Lambert, A.; Schols, E.; Comte, E.; Leenman, R.N.; Blom, R.

    2015-01-01

    Dimensional and phase changes of four candidate oxygen carrier materials for chemical looping combustion are investigated by dilatometry and high-temperature X-ray diffraction during four redox cycles. NiO/Ni2AlO4 does not exhibit significant dimensional changes during cycling, and it is shown that

  14. Simulation and validation of chemical-looping combustion using ASPEN plus

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Ling [Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013 (China); Department of Mechanical Engineering and Materials Science, Washington University, St. Louis, MO 63130 (United States); Zhang, Zheming; Agarwal, Ramesh K. [Department of Mechanical Engineering and Materials Science, Washington University, St. Louis, MO 63130 (United States)

    2013-07-01

    Laboratory-scale experimental studies have demonstrated that Chemical-Looping Combustion (CLC) is an advanced technology which holds great potential for high-efficiency low-cost carbon capture. The generated syngas in CLC is subsequently oxidized to CO2 and H2O by reaction with an oxygen carrier. In this paper, process-level models of CLC are established in ASPEN Plus code for detailed simulations. The entire CLC process, from the beginning of coal gasification to reduction and oxidation of the oxygen carrier is modeled. The heat content of each major component such as fuel and air reactors and air/flue gas heat exchangers is carefully examined. Large amount of energy is produced in the fuel reactor, but energy needs to be supplied to the air reactor. The overall performance and efficiency of the modeled CLC systems are also evaluated.

  15. Apparatus and method for solid fuel chemical looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Siriwardane, Ranjani V; Weber, Justin M

    2015-04-14

    The disclosure provides an apparatus and method utilizing fuel reactor comprised of a fuel section, an oxygen carrier section, and a porous divider separating the fuel section and the oxygen carrier section. The porous divider allows fluid communication between the fuel section and the oxygen carrier section while preventing the migration of solids of a particular size. Maintaining particle segregation between the oxygen carrier section and the fuel section during solid fuel gasification and combustion processes allows gases generated in either section to participate in necessary reactions while greatly mitigating issues associated with mixture of the oxygen carrier with char or ash products. The apparatus and method may be utilized with an oxygen uncoupling oxygen carrier such as CuO, Mn.sub.3O.sub.4, or Co.sub.3O.sub.4, or utilized with a CO/H.sub.2 reducing oxygen carrier such as Fe.sub.2O.sub.3.

  16. Chemical looping combustion: A new low-dioxin energy conversion technology.

    Science.gov (United States)

    Hua, Xiuning; Wang, Wei

    2015-06-01

    Dioxin production is a worldwide concern because of its persistence and carcinogenic, teratogenic, and mutagenic effects. The pyrolysis-chemical looping combustion process of disposing solid waste is an alternative to traditional solid waste incineration developed to reduce the dioxin production. Based on the equilibrium composition of the Deacon reaction, pyrolysis gas oxidized by seven common oxygen carriers, namely, CuO, NiO, CaSO4, CoO, Fe2O3, Mn3O4, and FeTiO3, is studied and compared with the pyrolysis gas directly combusted by air. The result shows that the activity of the Deacon reaction for oxygen carriers is lower than that for air. For four typical oxygen carriers (CuO, NiO, Fe2O3, and FeTiO3), the influences of temperature, pressure, gas composition, and tar on the Deacon reaction are discussed in detail. According to these simulation results, the dioxin production in China, Europe, the United States, and Japan is predicted for solid waste disposal by the pyrolysis-chemical looping combustion process. Thermodynamic analysis results in this paper show that chemical looping combustion can reduce dioxin production in the disposal of solid waste. Copyright © 2015. Published by Elsevier B.V.

  17. Separation of carbon dioxide with the use of chemical-looping combustion and gasification of fuels

    Science.gov (United States)

    Ryabov, G. A.; Folomeev, O. M.; Litun, D. S.; Sankin, D. A.

    2009-06-01

    Matters regarding using new technology for chemical-looping combustion of fuels for solving the problem of separation and disposal of artificial CO2 (CO2 sequestration) are discussed. The primary results of investigations and possible schemes for implementing the processes in pilot and commercial installations are presented. Their technical and economic indicators are estimated, and a possibility of disposing CO2 produced during electricity generation is considered.

  18. Simulations of a Circulating Fluidized Bed Chemical Looping Combustion System Utilizing Gaseous Fuel Simulation de la combustion en boucle chimique d’une charge gazeuse dans un lit fluidisé circulant

    Directory of Open Access Journals (Sweden)

    Mahalatkar K.

    2011-05-01

    Full Text Available Numerical studies using Computational Fluid Dynamics (CFD have been carried out for a complete circulating fluidized bed chemical looping combustor described in the literature (Abad et al., 2006 Fuel 85, 1174-1185. There have been extensive experimental studies in Chemical Looping Combustion (CLC, however CFD simulations of this concept are quite limited. The CLC experiments that were simulated used methane as fuel. A 2-D continuum model was used to describe both the gas and solid phases. Detailed sub-models to account for fluid-particle and particleparticle interaction forces were included. Global models of fuel and carrier chemistry were utilized. The results obtained from CFD were compared with experimental outlet species concentrations, solid circulation rates, solid mass distribution in the reactors, and leakage and dilution rates. The transient CFD simulations provided a reasonable match with the reported experimental data. Des études numériques de simulation des écoulements (CFD ont été réalisées sur un lit fluidisé circulant opérant en combustion par boucle chimique (CLC décrit dans la littérature (Abad et al., 2006 Fuel 85, 1174-1185. Si de nombreuses études expérimentales ont été conduites pour étudier le procédé CLC, les études concernant la simulation des écoulements par CFD de ce concept sont très limitées. Le système de combustion en boucle chimique simulé dans cette étude concerne la combustion d’une charge gazeuse (méthane. Un modèle 2-D à deux phases continues a été utilisé pour décrire les phases gaz et solide avec des sous-modèles détaillés pour décrire les forces d’interactions entre fluideparticule et particule-particule. Des modèles cinétiques globaux ont été intégrés pour décrire les réactions de combustion et de transformation du matériau transporteur d’oxygène. Les résultats obtenus par CFD ont été comparés aux concentrations expérimentales mesurées des diff

  19. Electric arc furnace dust as an alternative low-cost oxygen carrier for chemical looping combustion.

    Science.gov (United States)

    Kuo, Yu-Lin; Huang, Wei-Chen; Tseng, Yao-Hsuan; Chang, Shu-Huai; Ku, Young; Lee, Hao-Yeh

    2018-01-15

    The relative abundance and low cost of electric arc furnace dust (EAFD) make it a viable oxygen carrier for chemical looping combustion (CLC) system. Under a reducing agent, zinc ferrite (ZnFe2O4) phase in EAFD releases zinc vapor in a complex gas-solid reaction. In an effort to suppress the emission of zinc vapor, the reaction mechanism of ZnFe2O4 prepared as an oxygen carrier in a redox cycling test is primarily discussed, as well as the issue of coupling with an inert Al2O3 support. The study focused the investigation on redox cycling behavior and CO2 conversion in ZnFe2O4/Al2O3 and EAFD/Al2O3 systems using a thermogravimetric analyzer (TGA) and fixed-bed reactor (FxBR). In a lab-scaled semi-fluidized bed reactor (semi-FzBR) of EAFD/Al2O3 as an oxygen carrier system, a high CO gas yield approximately 0.98 after fifty redox cycles is also experimentally obtained. It can be anticipated that the use of EAFD/Al2O3 system as an oxygen carrier in a reversible CLC process could be economical and environmentally beneficial. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. A reduced fidelity model for the rotary chemical looping combustion reactor

    KAUST Repository

    Iloeje, Chukwunwike O.

    2017-01-11

    The rotary chemical looping combustion reactor has great potential for efficient integration with CO capture-enabled energy conversion systems. In earlier studies, we described a one-dimensional rotary reactor model, and used it to demonstrate the feasibility of continuous reactor operation. Though this detailed model provides a high resolution representation of the rotary reactor performance, it is too computationally expensive for studies that require multiple model evaluations. Specifically, it is not ideal for system-level studies where the reactor is a single component in an energy conversion system. In this study, we present a reduced fidelity model (RFM) of the rotary reactor that reduces computational cost and determines an optimal combination of variables that satisfy reactor design requirements. Simulation results for copper, nickel and iron-based oxygen carriers show a four-order of magnitude reduction in simulation time, and reasonable prediction accuracy. Deviations from the detailed reference model predictions range from 3% to 20%, depending on oxygen carrier type and operating conditions. This study also demonstrates how the reduced model can be modified to deal with both optimization and design oriented problems. A parametric study using the reduced model is then applied to analyze the sensitivity of the optimal reactor design to changes in selected operating and kinetic parameters. These studies show that temperature and activation energy have a greater impact on optimal geometry than parameters like pressure or feed fuel fraction for the selected oxygen carrier materials.

  1. Numerical investigation of the role of clustering during oxygen-carrier regeneration in Chemical Looping Combustion

    Science.gov (United States)

    Goyal, Himanshu; Pepiot, Perrine

    2016-11-01

    In the air-reactor of a dual-bed Chemical Looping Combustion (CLC) system, the spent oxygen-carrier, in the form of metal or reduced metal oxide, is oxidized with air, typically in a high velocity riser reactor. Such a configuration provides challenging modeling issues, as the granular flow is characterized by a highly fluctuating solid volume fraction due to the formation of dense clusters. This may strongly affect the solid residence time in the air-reactor, and therefore, the extent of the oxygen-carrier regeneration and ultimately, the overall reactivity of the carrier in the fuel reactor. Here, we investigate how clustering impacts gas-solid chemical reactions in the reactor using a detailed Lagrange-Euler computational framework. The simulations account for both mass and heat transfer between the gas phase and the metal oxide particles, and the evolution of oxygen content of the metal oxide particles, or equivalently, their degree of oxidation. Two particle models of different complexity are considered. Results are analyzed to quantify the relative importance on the regeneration process of the reactor hydrodynamics. This material is based upon work supported by the National Science Foundation under Grant No. CBET-1638837.

  2. Off-design performance of a chemical looping combustion (CLC) combined cycle: effects of ambient temperature

    Science.gov (United States)

    Chi, Jinling; Wang, Bo; Zhang, Shijie; Xiao, Yunhan

    2010-02-01

    The present work investigates the influence of ambient temperature on the steady-state off-design thermodynamic performance of a chemical looping combustion (CLC) combined cycle. A sensitivity analysis of the CLC reactor system was conducted, which shows that the parameters that influence the temperatures of the CLC reactors most are the flow rate and temperature of air entering the air reactor. For the ambient temperature variation, three off-design control strategies have been assumed and compared: 1) without any Inlet Guide Vane (IGV) control, 2) IGV control to maintain air reactor temperature and 3) IGV control to maintain constant fuel reactor temperature, aside from fuel flow rate adjusting. Results indicate that, compared with the conventional combined cycle, due to the requirement of pressure balance at outlet of the two CLC reactors, CLC combined cycle shows completely different off-design thermodynamic characteristics regardless of the control strategy adopted. For the first control strategy, temperatures of the two CLC reactors both rise obviously as ambient temperature increases. IGV control adopted by the second and the third strategy has the effect to maintain one of the two reactors' temperatures at design condition when ambient temperature is above design point. Compare with the second strategy, the third would induce more severe decrease of efficiency and output power of the CLC combined cycle.

  3. Analysis of thermally coupled chemical looping combustion-based power plants with carbon capture

    KAUST Repository

    Iloeje, Chukwunwike

    2015-04-01

    © 2015 Elsevier Ltd. A number of CO2 capture-enabled power generation technologies have been proposed to address the negative environmental impact of CO2 emission. One important barrier to adopting these technologies is the associated energy penalty. Chemical-looping Combustion (CLC) is an oxy-combustion technology that can significantly lower this penalty. It utilizes an oxygen carrier to transfer oxygen from air/oxidizing stream in an oxidation reactor to the fuel in a reduction reactor. Conventional CLC reactor designs employ two separate reactors, with metal/metal oxide particles circulating pneumatically in-between. One of the key limitations of these designs is the entropy generation due to reactor temperature difference, which lowers the cycle efficiency. Zhao et al. (Zhao et al., 2014; Zhao and Ghoniem, 2014) proposed a new CLC rotary reactor design, which overcomes this limitation. This reactor consists of a single rotating wheel with micro-channels designed to maintain thermal equilibrium between the fuel and air sides. This study uses three thermodynamic models of increasing fidelity to demonstrate that the internal thermal coupling in the rotary CLC reactor creates the potential for improved cycle efficiency. A theoretical availability model and an ideal thermodynamic cycle model are used to define the efficiency limits of CLC systems, illustrate the impact of reactor thermal coupling and discuss relevant criteria. An Aspen Plus® model of a regenerative CLC cycle is then used to show that this thermal coupling raises the cycle efficiency by up to 2% points. A parametric study shows that efficiency varies inversely with pressure, with a maximum of 51% at 3bar, 1000C and 60% at 4bar, 1400C. The efficiency increases with CO2 fraction at high pressure ratios but exhibits a slight inverse dependence at low pressure ratios. The parametric study shows that for low purge steam demand, steam generation improves exhaust heat recovery and increases efficiency

  4. Gasification Coupled Chemical Looping Combustion of Coal: A Thermodynamic Process Design Study

    OpenAIRE

    Borkhade, Sonali A.; Shriwas, Preksha A.; Ganesh R. Kale

    2013-01-01

    A thermodynamic investigation of gasification coupled chemical looping combustion (CLC) of carbon (coal) is presented in this paper. Both steam and CO2 are used for gasification within the temperature range of 500–1200°C. Chemical equilibrium model was considered for the gasifier and CLC fuel reactor. The trends in product compositions and energy requirements of the gasifier, fuel reactor, and air reactor were determined. Coal (carbon) gasification using 1.5 mol H2O and 1.5 mol CO2 per mole c...

  5. Experimental Investigation of CaMnO3−δ Based Oxygen Carriers Used in Continuous Chemical-Looping Combustion

    Directory of Open Access Journals (Sweden)

    Peter Hallberg

    2014-01-01

    Full Text Available Three materials of perovskite structure, CaMn1−xMxO3−δ (M = Mg or Mg and Ti, have been examined as oxygen carriers in continuous operation of chemical-looping combustion (CLC in a circulating fluidized bed system with the designed fuel power 300 W. Natural gas was used as fuel. All three materials were capable of completely converting the fuel to carbon dioxide and water at 900°C. All materials also showed the ability to release gas phase oxygen when fluidized by inert gas at elevated temperature (700–950°C; that is, they were suitable for chemical looping with oxygen uncoupling (CLOU. Both fuel conversion and oxygen release improved with temperature. All three materials also showed good mechanical integrity, as the fraction of fines collected during experiments was small. These results indicate that the materials are promising oxygen carriers for chemical-looping combustion.

  6. A novel reactor configuration for packed bed chemical-looping combustion of syngas

    Energy Technology Data Exchange (ETDEWEB)

    Hamers, H.P.; Gallucci, F.; Van Sint Annaland, M. [Multiphase Reactor Group, Chemical Process Intensification, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Cobden, P.D. [Energy Research Centre of the Netherlands (ECN), P.O. Box 1, 1755 ZG Petten (Netherlands); Kimball, E. [TNO Gas Treatment, P.O. Box 6000, 2600 JA Delft (Netherlands)

    2013-08-15

    This study reports on the application of chemical looping combustion (CLC) in pressurized packed bed reactors using syngas as a fuel. High pressure operation of CLC in packed bed has a different set of challenges in terms of material properties, cycle and reactor design compared to fluidized bed operation. However, high pressure operation allows the use of inherently more efficient power cycles than low pressure fluidized bed solutions. This paper quantifies the challenges in high pressure operation and introduces a novel reactor concept with which those challenges can be addressed. Continuous cyclic operation of a packed bed CLC system is simulated in a 1D numerical reactor model. Importantly, it is demonstrated that the temperature profiles that can occur in a packed bed reactor as a result of the different process steps do not accumulate, and have a negligible effect on the overall performance of the system. Moreover, it has been shown that an even higher energy efficiency can be achieved by feeding the syngas from the opposite direction during the reduction step (i.e. countercurrent operation). Unfortunately, in this configuration mode, more severe temperature fluctuations occur in the reactor exhaust, which is disadvantageous for the operation of a downstream gas turbine. Finally, a novel reactor configuration is introduced in which the desired temperature rise for obtained hot pressured air suitable for a gas turbine is obtained by carrying out the process with two packed bed reactor in series (two-stage CLC). This is shown to be a good alternative to the single bed configuration, and has the added advantage of decreasing the demands on both the oxygen carrier and the reactor materials and design specification.

  7. Reactor design, cold-model experiment and CFD modeling for chemical looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Shaohua; Ma, Jinchen; Hu, Xintao; Zhao, Haibo; Wang, Baowen; Zheng, Chuguang [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion

    2013-07-01

    Chemical looping combustion (CLC) is an efficient, clean and cheap technology for CO{sub 2} capture, and an interconnected fluidized bed is more appropriate solution for CLC. This paper aims to design a reactor system for CLC, carry out cold-model experiment of the system, and model fuel reactor using commercial CFD software. As for the CLC system, the air reactor (AR) is designed as a fast fluidized bed while the fuel reactor (FR) is a bubbling bed; a cyclone is used for solid separation of the AR exit flow. The AR and FR are separated by two U-type loop seals to remain gas sealed. Considered the chemical kinetics of oxygen carrier, fluid dynamics, pressure balance and mass balance of the system simultaneously, some key design parameters of a CH{sub 4}-fueled and Fe{sub 2}O{sub 3}/Al{sub 2}O{sub 3}-based CLC reactor (thermal power of 50 kWth) are determined, including key geometric parameters (reactor cross-sectional area and reactor height) and operation parameters (bed material quantity, solid circulation rate, apparent gas velocity of each reactor). A cold-model bench having same geometric parameters with its prototype is built up to study the effects of various operation conditions (including gas velocity in the reactors and loop seals, and bed material height, etc.) on the solids circulation rate, gas leakage, and pressure balance. It is witnessed the cold-model system is able to meet special requirements for CLC system such as gas sealing between AR and FR, the circulation rate and particles residence time. Furthermore, the thermal FR reactor with oxygen carrier of Fe{sub 2}O{sub 3}/Al{sub 2}O{sub 3} and fuel of CH{sub 4} is simulated by commercial CFD solver FLUENT. It is found that for the design case the combustion efficiency of CH{sub 4} reaches 88.2%. A few part of methane is unburned due to fast, large bubbles rising through the reactor.

  8. Techno-economic investigation of a chemical looping combustion based power plant.

    Science.gov (United States)

    Porrazzo, Rosario; White, Graeme; Ocone, Raffaella

    2016-10-20

    Among the well-known state-of-the-art technologies for CO2 capture, Chemical Looping Combustion (CLC) stands out for its potential to capture CO2 efficiently from a fuel power plant. CLC involves the combustion of carbonaceous fuel such as coal-derived syngas or natural gas via a redox chemical reaction with a solid oxygen carrier circulating between two fluidised beds. Avoided NOx emissions, high CO2 capture and thermal efficiency are the key concepts that make worth the investigation of this technology. One of the main issues about CLC might concern the impact of the solid metal oxides price and lifetime on the Levelised Cost Of the Electricity (LCOE). A natural gas fired power plant embedding a CLC unit is presented in this work. Detailed fluidised bed models are implemented in Aspen Plus software. Kinetics and hydrodynamics are taken into account to evaluate their effect on the total solid inventory required for full fuel conversion. The models are incorporated into a power plant and a detailed economic evaluation is undertaken by varying two relevant parameters: fuel price and lifetime of the solid particles. The effect of these parameters on the LCOE is investigated and a comparison between CLC and a post-combustion technology employing amines (e.g. monoethanolamine, MEA) is presented. It is shown that the CLC power plant under study leads to a lower LCOE compared to the current MEA post-combustion solution.

  9. Energy and exergy analysis of chemical looping combustion technology and comparison with pre-combustion and oxy-fuel combustion technologies for CO2 capture

    OpenAIRE

    Mukherjee, Sanjay; Kumar, Prashant; Yang, Aidong; Fennell, Paul

    2015-01-01

    Abstract Carbon dioxide (CO2) emitted from conventional coal-based power plants is a growing concern for the environment. Chemical looping combustion (CLC), pre-combustion and oxy-fuel combustion are promising CO2 capture technologies which allow clean electricity generation from coal in an integrated gasification combined cycle (IGCC) power plant. This work compares the characteristics of the above three capture technologies to those of a conventional IGCC plant without CO2 capture. CLC tech...

  10. Chemical Looping Combustion of Hematite Ore with Methane and Steam in a Fluidized Bed Reactor

    Directory of Open Access Journals (Sweden)

    Samuel Bayham

    2017-08-01

    Full Text Available Chemical looping combustion is considered an indirect method of oxidizing a carbonaceous fuel, utilizing a metal oxide oxygen carrier to provide oxygen to the fuel. The advantage is the significantly reduced energy penalty for separating out the CO2 for reuse or sequestration in a carbon-constrained world. One of the major issues with chemical looping combustion is the cost of the oxygen carrier. Hematite ore is a proposed oxygen carrier due to its high strength and resistance to mechanical attrition, but its reactivity is rather poor compared to tailored oxygen carriers. This problem is further exacerbated by methane cracking, the subsequent deposition of carbon and the inability to transfer oxygen at a sufficient rate from the core of the particle to the surface for fuel conversion to CO2. Oxygen needs to be readily available at the surface to prevent methane cracking. The purpose of this work was to demonstrate the use of steam to overcome this issue and improve the conversion of the natural gas to CO2, as well as to provide data for computational fluid dynamics (CFD validation. The steam will gasify the deposited carbon to promote the methane conversion. This work studies the performance of hematite ore with methane and steam mixtures in a 5 cm fluidized bed up to approximately 140 kPa. Results show an increased conversion of methane in the presence of steam (from 20–45% without steam to 60–95% up to a certain point, where performance decreases. Adding steam allows the methane conversion to carbon dioxide to be similar to the overall methane conversion; it also helped to prevent carbon accumulation from occurring on the particle. In general, the addition of steam to the feed gas increased the methane conversion. Furthermore, the addition of steam caused the steam methane reforming reaction to form more hydrogen and carbon monoxide at higher steam and methane concentrations, which was not completely converted at higher concentrations and

  11. 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.

  12. Particulate Formation from a Copper Oxide-Based Oxygen Carrier in Chemical Looping Combustion for CO2 Capture

    Science.gov (United States)

    Attrition behavior and particle loss of a copper oxide-based oxygen carrier from a methane chemical looping combustion (CLC) process was investigated in a fluidized bed reactor. The aerodynamic diameters of most elutriated particulates, after passing through a horizontal settling...

  13. Chemical looping combustion of biomass-derived syngas using ceria-supported oxygen carriers.

    Science.gov (United States)

    Huang, H B; Aisyah, L; Ashman, P J; Leung, Y C; Kwong, C W

    2013-07-01

    Cu, Ni and Fe oxides supported on ceria were investigated for their performance as oxygen carriers during the chemical looping combustion of biomass-derived syngas. A complex gas mixture containing CO, H2, CO2, CH4 and other hydrocarbons was used to simulate the complex fuel gas environment derived from biomass gasification. Results show that the transfer of the stored oxygen into oxidants for the supported Cu and Ni oxides at 800°C for the combustion of syngas was effective (>85%). The unsupported Cu oxide showed high oxygen carrying capacity but particle sintering was observed at 800°C. A reaction temperature of 950°C was required for the supported Fe oxides to transfer the stored oxygen into oxidants effectively. Also, for the complex fuel gas environment, the supported Ni oxide was somewhat effective in reforming CH4 and other light hydrocarbons into CO, which may have benefits for the reduction of tar produced during biomass pyrolysis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Finial Scientific/Technical Report: Application of a Circulating Fluidized Bed Process for the Chemical Looping Combustion of Solid Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Wei-Ping Pan; Dr. John T. Riley

    2005-10-10

    Chemical Looping Combustion is a novel combustion technology for the inherent separation of the greenhouse gas, CO{sub 2}. In 1983, Richter and Knoche proposed reversible combustion, which utilized both the oxidation and reduction of metal. Metal associated with its oxidized form as an oxygen carrier was circulated between two reactors--oxidizer and reducer. In the reducer, the solid oxygen carrier reacts with the fuel to produce CO{sub 2}, H{sub 2}O and elemental metal only. Pure CO{sub 2} will be obtained in the exit gas stream from the reducer after H{sub 2}O is condensed. The pure CO{sub 2} is ready for subsequent sequestration. In the oxidizer, the elemental metal reacts with air to form metal oxide and separate oxygen from nitrogen. Only nitrogen and some unused oxygen are emitted from the oxidizer. The advantage of CLC compared to normal combustion is that CO{sub 2} is not diluted with nitrogen but obtained in a relatively pure form without any energy needed for separation. In addition to the energy-free purification of CO{sub 2}, the CLC process also provides two other benefits. First, NO{sub x} formation can be largely eliminated. Secondly, the thermal efficiency of a CLC system is very high. Presently, the CLC process has only been used with natural gas. An oxygen carrier based on an energy balance analysis and thermodynamics analysis was selected. Copper (Cu) seems to be the best choice for the CLC system for solid fuels. From this project, the mechanisms of CuO reduction by solid fuels may be as follows: (1) If pyrolysis products of solid fuels are available, reduction of CuO could start at about 400 C or less. (2) If pyrolysis products of solid fuels are unavailable and the reduction temperature is lower, reduction of CuO could occur at an onset temperature of about 500 C, char gasification reactivity in CO{sub 2} was lower at lower temperatures. (3) If pyrolysis products of solid fuels are unavailable and the reduction temperature is higher than 750 C

  15. Exergy Analysis of a Syngas-Fueled Combined Cycle with Chemical-Looping Combustion and CO2 Sequestration

    Directory of Open Access Journals (Sweden)

    Álvaro Urdiales Montesino

    2016-08-01

    Full Text Available Fossil fuels are still widely used for power generation. Nevertheless, it is possible to attain a short- and medium-term substantial reduction of greenhouse gas emissions to the atmosphere through a sequestration of the CO2 produced in fuels’ oxidation. The chemical-looping combustion (CLC technique is based on a chemical intermediate agent, which gets oxidized in an air reactor and is then conducted to a separated fuel reactor, where it oxidizes the fuel in turn. Thus, the oxidation products CO2 and H2O are obtained in an output flow in which the only non-condensable gas is CO2, allowing the subsequent sequestration of CO2 without an energy penalty. Furthermore, with shrewd configurations, a lower exergy destruction in the combustion chemical transformation can be achieved. This paper focus on a second law analysis of a CLC combined cycle power plant with CO2 sequestration using syngas from coal and biomass gasification as fuel. The key thermodynamic parameters are optimized via the exergy method. The proposed power plant configuration is compared with a similar gas turbine system with a conventional combustion, finding a notable increase of the power plant efficiency. Furthermore, the influence of syngas composition on the results is investigated by considering different H2-content fuels.

  16. Effect of fuel particle size on reaction rate in chemical looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Iggland, M.; Leion, H.; Mattisson, T.; Lyngfelt, A. [ETH, Zurich (Switzerland). Inst. of Process Engineering

    2010-11-15

    Chemical looping combustion (CLC) uses an oxygen carrier circulating between an air and a fuel reactor to replace direct burning of fuels in air. The very low energy penalty for CO{sub 2} separation in CLC gives it the potential to become an important technology on the way to a CO{sub 2} neutral energy supply. In this work, the influence of the particle size of coal on the rate of reaction of the coal was investigated in a bed of oxygen carrier. In order to do this, a method to quench the reaction of coal with oxygen carriers at a specified time and measure the particle size distribution of the remaining coal was developed. Three size fractions of coal were used in the experiments: 90-125, 180-212 and 250-355 mu m. Particle size distributions of the fuel show a decrease in particle size with time. The influence of devolatilisation of the coal on the coal particle size was measured, showing that coal particles do not break in the fluidized bed reactor used for the experiments. Reaction rates based on measurements of gas phase concentrations of CO{sub 2}, CO and CH{sub 4} showed that the reaction rate is independent of the particle size. These results are in line with literature findings, as studies have shown that carbon gasification is size-independent at conditions similar to those in the performed CLC experiments.

  17. Design of a rotary reactor for chemical-looping combustion. Part 1: Fundamentals and design methodology

    KAUST Repository

    Zhao, Zhenlong

    2014-04-01

    Chemical-looping combustion (CLC) is a novel and promising option for several applications including carbon capture (CC), fuel reforming, H 2 generation, etc. Previous studies demonstrated the feasibility of performing CLC in a novel rotary design with micro-channel structures. In the reactor, a solid wheel rotates between the fuel and air streams at the reactor inlet, and depleted air and product streams at exit. The rotary wheel consists of a large number of micro-channels with oxygen carriers (OC) coated on the inner surface of the channel walls. In the CC application, the OC oxidizes the fuel while the channel is in the fuel zone to generate undiluted CO2, and is regenerated while the channel is in the air zone. In this two-part series, the effect of the reactor design parameters is evaluated and its performance with different OCs is compared. In Part 1, the design objectives and criteria are specified and the key parameters controlling the reactor performance are identified. The fundamental effects of the OC characteristics, the design parameters, and the operating conditions are studied. The design procedures are presented on the basis of the relative importance of each parameter, enabling a systematic methodology of selecting the design parameters and the operating conditions with different OCs. Part 2 presents the application of the methodology to the designs with the three commonly used OCs, i.e., nickel, copper, and iron, and compares the simulated performances of the designs. © 2013 Elsevier Ltd. All rights reserved.

  18. Metal ferrite oxygen carriers for chemical looping combustion of solid fuels

    Energy Technology Data Exchange (ETDEWEB)

    Siriwardane, Ranjani V.; Fan, Yueying

    2017-01-31

    The disclosure provides a metal ferrite oxygen carrier for the chemical looping combustion of solid carbonaceous fuels, such as coal, coke, coal and biomass char, and the like. The metal ferrite oxygen carrier comprises MFe.sub.xO.sub.y on an inert support, where MFe.sub.xO.sub.y is a chemical composition and M is one of Mg, Ca, Sr, Ba, Co, Mn, and combinations thereof. For example, MFe.sub.xO.sub.y may be one of MgFe.sub.2O.sub.4, CaFe.sub.2O.sub.4, SrFe.sub.2O.sub.4, BaFe.sub.2O.sub.4, CoFe.sub.2O.sub.4, MnFeO.sub.3, and combinations thereof. The MFe.sub.xO.sub.y is supported on an inert support. The inert support disperses the MFe.sub.xO.sub.y oxides to avoid agglomeration and improve performance stability. In an embodiment, the inert support comprises from about 5 wt. % to about 60 wt. % of the metal ferrite oxygen carrier and the MFe.sub.xO.sub.y comprises at least 30 wt. % of the metal ferrite oxygen carrier. The metal ferrite oxygen carriers disclosed display improved reduction rates over Fe.sub.2O.sub.3, and improved oxidation rates over CuO.

  19. Reduction Kinetics of a CasO4 Based Oxygen Carrier for Chemical-Looping Combustion

    Science.gov (United States)

    Xiao, R.; Song, Q. L.; Zheng, W. G.; Deng, Z. Y.; Shen, L. H.; Zhang, M. Y.

    The CaSO4 based oxygen carrier has been proposed as an alternative low cost oxygen carrier for Chemical-looping combustion (CLC) of coal. The reduction of CaSO4 to CaS is an important step for the cyclic process of reduction/oxidation in CLC of coal with CaSO4 based oxygen carrier. Thermodynamic analysis of CaSO4 oxygen carrier with CO based on the principle of Gibbs free energy minimization show that the essentially high purity of CO2 can be obtained, while the solid product is CaS instead of CaO. The intrinsic reduction kinetics of a CaSO4 based oxygen carrier with CO was investigated in a differential fixed bed reactor. The effects of gas partial pressure (20%-70%) and temperature (880-950°C) on the reduction were investigated. The reduction was described with shrinking unreacted core model. Experimental results of CO partial pressure on the solid conversion show that the reduction of fresh oxygen carriers is of first order with respect to the CO partial pressure. Both chemical reaction control and product layer diffusion control determine the reduction rate. The dependences of reaction rate constant and effective diffusivity with temperature were both obtained. The kinetic equation well predicted the experimental data.

  20. 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.

  1. Investigation of Coal Fueled Chemical Looping Combustion Using Fe3O4 as Oxygen Carrier

    Science.gov (United States)

    Xlang, Wenguo; Sun, Xiaoyan; Wangt, Sha; Tian, Wendong; Xu, Xiang; Xu, Yanji; Xiao, Yunhan

    Chemical-looping combustion (CLC) is a novel combustion technique with CO2 separation. Magnetite (Fe3O4) was selected as the oxygen carrier and Shenhua coal (Inner Mongolia, China) as the fuel for this study. The influences of operation temperatures, and coal to Fe3O4 mass ratios on the reduction characteristics of the oxygen carrier were investigated using an atmosphere TGA. The sample, comprised of 2.25mg coal and 12.75mg Fe3O4, was heated to 1000°C. Experimental results show that the reaction between the coal volatile and Fe3O4 began at 700°C while the reaction between the coal char and Fe3O4 occurred at 800°C and reached a peak at 900°C. Fe3O4 was fully reduced into FeO, while some FeO was further reduced to Fe. As the operation temperature rises, the reduction conversion rate increases. At the temperatures of 850°C, 900°C, and 950°C, the reduction conversion rates were 37.1%, 46.5%, and 54.1% respectively. When the mass ratios of coal to Fe3O4 were 5/95, 10/90, 15/85, and 20/80, the reduction conversion rates were 29.5%,40.8%,46.5%, and 46.6% respectively. With the increase of coal to Fe3O4 mass ratio, the conversion rate increases first and then changes no more. There exists an optimal coal to Fe3O4 mass ratio.

  2. A two-compartment fluidized bed reactor for CO{sub 2} capture by chemical-looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Kronberger, B.; Loeffler, G.; Hofbauer, H. [Vienna University of Technology, Institute of Chemical Engineering, Getreidemarkt 9/1663, A-1060 Vienna (Austria); Johansson, E.; Mattisson, T.; Lyngfelt, A. [Chalmers University of Technology, Department of Energy Conversion, S-412 96 Gothenburg (Sweden)

    2004-12-01

    Chemical-looping combustion (CLC) is a combustion method for a gaseous fuel with inherent separation of the greenhouse gas carbon dioxide. A CLC system consists of two reactors, an air reactor and a fuel reactor, and an oxygen carrier circulating between the two reactors. The oxygen carrier transfers the oxygen from the air to the fuel. The flue gas from the fuel reactor consists of carbon dioxide and water, while the flue gas from the air reactor is nitrogen from the air. A two-compartment fluidized bed CLC system was designed and tested using a flow model in order to find critical design parameters. Gas velocities and slot design were varied, and the solids circulation rate and gas leakage between the reactors were measured. The solids circulation rate was found to be sufficient. The gas leakage was somewhat high but could be reduced by altering the slot design. Finally, a hot laboratory CLC system is presented with an advanced design for the slot and also with the possibility for inert gas addition into the downcomer for solids flow increase. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

  3. Experimental evaluation of a Chinese sulfur-containing lean iron ore as the oxygen carrier for chemical-looping combustion

    OpenAIRE

    Wang, Xiaojia; Hao LIU; Jin, Baosheng; Zhao, Jie; Sun, Chenggong; Snape, Colin E.

    2016-01-01

    A series of chemical-looping combustion (CLC) tests were conducted in a thermogravimetric analysis (TGA) reactor to investigate the potential of a Chinese sulfur-containing lean iron ore as the oxygen carrier. Two main products of solidfuel pyrolysis and gasification, namely, CH4 and CO, were selected as the reducing gases. Consecutive reduction−oxidation cycles were first carried out in the TGA reactor to evaluate the cyclic stability and agglomeration tendency of the oxygen carrier. The eff...

  4. Alstom's Chemical Looping Combustion Prototype for CO2 Capture from Existing Pulverized Coal-Fired Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Andrus, Jr., Herbert E. [Alstom Power Inc., Windsor, CT (United States); Chiu, John H. [Alstom Power Inc., Windsor, CT (United States); Edberg, Carl D. [Alstom Power Inc., Windsor, CT (United States); Thibeault, Paul R. [Alstom Power Inc., Windsor, CT (United States); Turek, David G. [Alstom Power Inc., Windsor, CT (United States)

    2012-09-30

    Alstom’s Limestone Chemical Looping (LCL™) process has the potential to capture CO2 from new and existing coal-fired power plants while maintaining high plant power generation efficiency. This new power plant concept is based on a hybrid combustion- gasification process utilizing high temperature chemical and thermal looping technology. This process could also be potentially configured as a hybrid combustion-gasification process producing a syngas or hydrogen for various applications while also producing a separate stream of CO2 for use or sequestration. The targets set for this technology is to capture over 90% of the total carbon in the coal at cost of electricity which is less than 20% greater than Conventional PC or CFB units. Previous work with bench scale test and a 65 kWt Process Development Unit Development (PDU) has validated the chemistry required for the chemical looping process and provided for the investigation of the solids transport mechanisms and design requirements. The objective of this project is to continue development of the combustion option of chemical looping (LCL-C™) by designing, building and testing a 3 MWt prototype facility. The prototype includes all of the equipment that is required to operate the chemical looping plant in a fully integrated manner with all major systems in service. Data from the design, construction, and testing will be used to characterize environmental performance, identify and address technical risks, reassess commercial plant economics, and develop design information for a demonstration plant planned to follow the proposed Prototype. A cold flow model of the prototype will be used to predict operating conditions for the prototype and help in operator training. Operation of the prototype will provide operator experience with this new technology and performance data of the LCL-C™ process, which will be applied to the commercial design and economics and plan for a future demonstration

  5. Mechanism of Methane Chemical Looping Combustion with Hematite Promoted with CeO 2

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Duane D.; Siriwardane, Ranjani

    2013-08-15

    Chemical looping combustion (CLC) is a promising technology for fossil fuel combustion that produces sequestration-ready CO{sub 2} stream, reducing the energy penalty of CO{sub 2} separation from flue gases. An effective oxygen carrier for CLC will readily react with the fuel gas and will be reoxidized upon contact with oxygen. This study investigated the development of a CeO{sub 2}-promoted Fe{sub 2}O{sub 3}-hematite oxygen carrier suitable for the methane CLC process. Composition of CeO{sub 2} is between 5 and 25 wt % and is lower than what is generally used for supports in Fe{sub 2}O{sub 3} carrier preparations. The incorporation of CeO{sub 2} to the natural ore hematite strongly modifies the reduction behavior in comparison to that of CeO{sub 2} and hematite alone. Temperature-programmed reaction studies revealed that the addition of even 5 wt % CeO{sub 2} enhances the reaction capacity of the Fe{sub 2}O{sub 3} oxygen carrier by promoting the decomposition and partial oxidation of methane. Fixed-bed reactor data showed that the 5 wt % cerium oxides with 95 wt % iron oxide produce 2 times as much carbon dioxide in comparison to the sum of carbon dioxide produced when the oxides were tested separately. This effect is likely due to the reaction of CeO{sub 2} with methane forming intermediates, which are reactive for extracting oxygen from Fe{sub 2}O{sub 3} at a considerably faster rate than the rate of the direct reaction of Fe{sub 2}O{sub 3} with methane. These studies reveal that 5 wt % CeO{sub 2}/Fe{sub 2}O{sub 3} gives stable conversions over 15 reduction/oxidation cycles. Lab-scale reactor studies (pulsed mode) suggest the methane reacts initially with CeO{sub 2} lattice oxygen to form partial oxidation products (CO + H{sub 2}), which continue to react with oxygen from neighboring Fe{sub 2}O{sub 3}, leading to its complete oxidation to form CO{sub 2}. The reduced cerium oxide promotes the methane decomposition reaction to form C + H{sub 2}, which continue to

  6. Processing and Evaluation of Next Generation Oxygen Carrier Materials for Chemical Looping Combustion

    Science.gov (United States)

    Hamedi Rad, Mina

    This study follows two methods to achieve a modified CaMnO 3-delta structure with higher oxygen capacity and stability. The first method is replacement of manganese with iron as a cheaper alternative and the second method is size effect investigations of A-site dopants on CaMn 0.9Fe0.1O3-delta and its oxygen capacity and stability. Solid state reaction followed by mechanical extrusion is used as the preparation method. All synthesized perovskites are characterized by TGA and XRD analyses. The samples of highest oxygen capacity and stability are further characterized by SEM and BET analyses. Oxygen uncoupling behavior and reactivity of these samples are also examined using a fluidized bed reactor performing Chemical Looping Combustion. The temperature effect is also investigated during chemical looping process at temperatures of 800, 850, 900 and 950 °C. In the first method, since calcium could not be incorporated in the structure, strontium is used as the A-site cation. SrFeO3-delta has shown to be more stable than CaMnO3-delta. However, because of low oxygen capacity, it is doped on the A-site (La and Ba) and B-site (Al, Ti, Mn, Co) by 10 mol% (Sr0.9La0.1FeO3-delta, Sr0.9Ba0.1FeO3-delta, SrFe0.9Al 0.1O3-delta, SrFe0.9Ti0.1O3-delta , SrFe0.9Mn0.1O3-delta, SrFe 0.9Co0.1O3-delta). Results reveal that manganese doped structure (SrFe0.9Mn0.1O3-delta) has the highest oxygen capacity. Adding more manganese to the structure increases the oxygen capacity even further. The best iron-based structure has 30 mol% manganese, doped on the B-site, having 28% mass change in an inert atmosphere (SrFe0.7Mn0.3O3-delta, SFM73) and high stability. Results of conducted experiments in second method demonstrated that Strontium doped perovskite (Ca0.9Sr0.1Mn0.9Fe 0.1O3-delta, CS91MF91) is the best synthesized oxygen carrier among all synthesized manganese and iron-based perovskites. This material shows excellent oxygen uptake and release (1.78 wt. %) and high stability. The reactivity and

  7. Rational Design of Mixed-Metal Oxides for Chemical Looping Combustion of Coal via Coupled Computational-Experimental Studies

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Amit; Li, Fanxing; Santiso, Erik

    2017-09-18

    Energy and global climate change are two grand challenges to the modern society. An urgent need exists for development of clean and efficient energy conversion processes. The chemical looping strategy, which utilizes regenerable oxygen carriers (OCs) to indirectly convert carbonaceous fuels via redox reactions, is considered to be one of the more promising approaches for CO2 capture by the U.S. Department of Energy (USDOE). To date, most long-term chemical looping operations were conducted using gaseous fuels, even though direct conversion of coal is more desirable from both economics and CO2 capture viewpoints. The main challenges for direct coal conversion reside in the stringent requirements on oxygen carrier performances. In addition, coal char and volatile compounds are more challenging to convert than gaseous fuels. A promising approach for direct conversion of coal is the so called chemical looping with oxygen uncoupling (CLOU) technique. In the CLOU process, a metal oxide that decomposes at the looping temperature, and releases oxygen to the gas phase is used as the OC. The overarching objective of this project was to discover the fundamental principles for rational design and optimization of oxygen carriers (OC) in coal chemical looping combustion (CLC) processes. It directly addresses Topic Area B of the funding opportunity announcement (FOA) in terms of “predictive description of the phase behavior and mechanical properties” of “mixed metal oxide” based OCs and rational development of new OC materials with superior functionality. This was achieved through studies exploring i) iron-containing mixed-oxide composites as oxygen carriers for CLOU, ii) Ca1-xAxMnO3-δ (A = Sr and Ba) as oxygen carriers for CLOU, iii) CaMn1-xBxO3-δ (B=Al, V, Fe, Co, and Ni) as oxygen carrier for CLOU and iv) vacancy creation energy in Mn-containing perovskites as an indicator chemical looping with oxygen uncoupling.

  8. Effects of Steam and CO2 in the Fluidizing Gas when Using Bituminous Coal in Chemical-Looping Combustion

    Science.gov (United States)

    Leion, H.; Lyngfelt, A.; Mattisson, T.

    Chemical-looping combustion (CLC) is a combustion technology where an oxygen carrier is used to transfer oxygen from the combustion air to the fuel in order to avoid direct contact between air and fuel. Thus, the CO2 is inherently separated from the flue gases with a potential for considerably lower energy penalty and cost compared to other techniques for CO2 separation. The oxygen carrier is circulated between two reactors, a fuel and an air reactor, where the flue gas from the air reactor contains oxygen depleted air and the flue gas from the fuel reactor contains mainly CO2 and H2O. The water can easily be condensed and the remaining CO2 can be transported for underground storage. Most of the prior work with CLC has focused on using natural gas and syngas as fuel and oxygen carrying material normally produced from pure chemicals. However, recent work on adapting the CLC process for solid fuels with ores and natural minerals as oxygen carrier shows promising results. This paper will present results from reactivity investigations in a laboratory fluidized-bed reactor system using previously investigated natural mineral ilmenite as oxygen carrier and a bituminous Colombian coal as fuel. Experiments were conducted at a temperature of 970°C with N2, steam, and/or CO2 in the fluidizing gas. Synergy effects between steam and CO2 on fuel conversion was noted. The results show that the fuel conversion was a roughly a factor 5 faster with steam as compared to CO2 in the fluidizing gas.

  9. Development of Computational Approaches for Simulation and Advanced Controls for Hybrid Combustion-Gasification Chemical Looping

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Abhinaya; Lou, Xinsheng; Neuschaefer, Carl; Chaudry, Majid; Quinn, Joseph

    2012-07-31

    This document provides the results of the project through September 2009. The Phase I project has recently been extended from September 2009 to March 2011. The project extension will begin work on Chemical Looping (CL) Prototype modeling and advanced control design exploration in preparation for a scale-up phase. The results to date include: successful development of dual loop chemical looping process models and dynamic simulation software tools, development and test of several advanced control concepts and applications for Chemical Looping transport control and investigation of several sensor concepts and establishment of two feasible sensor candidates recommended for further prototype development and controls integration. There are three sections in this summary and conclusions. Section 1 presents the project scope and objectives. Section 2 highlights the detailed accomplishments by project task area. Section 3 provides conclusions to date and recommendations for future work.

  10. Coprecipitated, copper-based, alumina-stabilized materials for carbon dioxide capture by chemical looping combustion.

    Science.gov (United States)

    Imtiaz, Qasim; Kierzkowska, Agnieszka Marta; Müller, Christoph Rüdiger

    2012-08-01

    Chemical looping combustion (CLC) has emerged as a carbon dioxide capture and storage (CCS) process to produce a pure stream of CO(2) at very low costs when compared with alternative CCS technologies, such as scrubbing with amines. From a thermodynamic point of view, copper oxide is arguably the most promising candidate for the oxygen carrier owing to its exothermic reduction and oxidation reactions and high oxygen-carrying capacity. However, the low melting point of pure copper of only 1085 °C has so far prohibited the synthesis of copper-rich oxygen carriers. This paper is concerned with the development of copper-based and Al(2)O(3)-stabilized oxygen carriers that contain a high mass fraction of CuO, namely, 82.4 wt %. The oxygen carriers were synthesized by using a coprecipitation technique. The synthesized oxygen carriers were characterized in detail with regards to their morphological properties, chemical composition, and surface topography. It was found that both the precipitating agent and the pH at which the precipitation was performed strongly influenced the structure and chemical composition of the oxygen carriers. In addition, XRD analysis confirmed that, for the majority of the precipitation conditions investigated, CuO reacted with Al(2)O(3) to form fully reducible CuAl(2)O(4). The redox characteristics of the synthesized materials were evaluated at 800 °C by using methane as the fuel and air for reoxidation. It was found that the oxygen-carrying capacity of the synthesized oxygen carriers was strongly influenced by both the precipitating agent and the pH at which the precipitation was performed; however, all oxygen carriers tested showed a stable cyclic oxygen-carrying capacity. The oxygen carriers synthesized at pH 5.5 using NaOH or Na(2)CO(3) as the precipitating agents were the best oxygen carriers synthesized owing to their high and stable oxygen transfer and uncoupling capacities. The excellent redox characteristics of the best oxygen carrier

  11. 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.

  12. The synergetic effect of metal oxide support on Fe2O3 for chemical looping combustion: A theoretical study

    Science.gov (United States)

    Qin, Wu; Wang, Yang; Dong, Changqing; Zhang, Junjiao; Chen, Qiuluan; Yang, Yongping

    2013-10-01

    This study deals with the synergetic effect of Al2O3 on Fe2O3 for chemical-looping combustion (CLC) of CO, in comparison with the synergetic effects of ZrO2 and MgO reported in our previous works. Property analysis of Fe2O3/Al2O3 shows that new bonds form cross the interface making Fe2O3 less prone to agglomerate on Al2O3, and 0.129 e transfers from Al2O3 to Fe2O3 to activate the electronic state of Fe2O3. Al2O3 [ZrO2 and MgO] favors the thermal stability of Fe2O3 by preventing the phase transformation, markedly regulates charge populations on the O-Fe bonds and their overlaps and hence tunes the redox properties of Fe2O3. The reaction mechanism analysis demonstrates that Al2O3 [ZrO2 and MgO] activates Fe2O3 for oxidizing CO into CO2 (accompanied by the reduction of Fe2O3) in the fuel reactor, which decrease the height of barrier energy (Ea), and the Ea follows clearly Fe2O3 > Fe2O3/Al2O3 > Fe2O3/MgO > Fe2O3/ZrO2. However, these supports usually increase the Ea for oxidizing Fe2O2 into Fe2O3 by O2 in the air reactor, and the Ea follows clearly Fe2O3/ZrO2 > Fe2O3/Al2O3 > Fe2O3/MgO > Fe2O3. It is argued that different supports could be applied to a given CLC system of different thermodynamic properties.

  13. Experimental Investigations on a Novel Chemical Looping Combustion Configuration Étude expérimentale d’une nouvelle configuration de combustion en boucle chimique

    Directory of Open Access Journals (Sweden)

    Yazdanpanah M.M.

    2011-04-01

    Full Text Available Chemical Looping Combustion (CLC is a promising novel combustion technology involving inherent separation of carbon dioxide with minimum energy penalty. An oxygen carrier is employed to continuously transfer oxygen from the air reactor to the fuel reactor where the oxygen is delivered to the fuel. Consequently, direct contact between the air and fuel is prevented. The resulting flue gas is CO2-rich, without N2 dilution. The reduced oxygen carrier is then transported back to the air reactor for re-oxidation purposes, hence forming a chemical loop. Various CLC configurations have already been developed and tested on laboratory scales. However, more investigations are required to achieve feasible CLC processes. Among the different points to address, control of the solid circulation rate between the two reactors is of the highest importance regarding its effect on achievement of an appropriate oxygen transfer rate and solid oxidation degrees. Moreover, minimization of gas leakage between the fuel and air reactors is another important issue to be considered. A novel CLC configuration is proposed where reactions are carried out in two interconnected bubbling fluidized beds. Solid circulation rate control is achieved independently of gas flow rate in the reactors through use of pneumatic non-mechanical valves (L-valves. Moreover, loopseals are employed to minimize gas leakage while transferring solids. Experimental results from operation of a 10 kWth equivalent cold prototype are presented in this paper. The effect of operating variables on the solid circulation rate, gas leakage between the two beds and the pressure balance on all of the process elements is studied. The results demonstrate stable solid circulation with efficient control of the solid flow rate and effective gas tightness of the system. La combustion en boucle chimique (CLC est une nouvelle technologie prometteuse qui implique la separation inherente du dioxyde de carbone avec une perte

  14. Reduction kinetics of iron-based oxygen carriers using methane for chemical-looping combustion

    Science.gov (United States)

    Luo, Ming; Wang, Shuzhong; Wang, Longfei; Lv, Mingming

    2014-12-01

    The performance of three iron-based oxygen carriers (pure Fe2O3, synthetic Fe2O3/MgAl2O4 and iron ore) in reduction process using methane as fuel is investigated in thermo-gravimetric analyzer (TGA). The reaction rate and mechanism between three oxygen carriers and methane are investigated. On the basis of reactivity in reduction process, it may be concluded that Fe2O3/MgAl2O4 has the best reactivity with methane. The reaction rate constant is found to be in the following order: Fe2O3/MgAl2O4 > pure Fe2O3 > iron ore and the activation energy varies between 49 and 184 kJ mol-1. Reduction reactions for the pure Fe2O3 and synthetic Fe2O3/MgAl2O4 are well represented by the reaction controlling mechanism, and for the iron ore the phase-boundary controlled (contracting cylinder) model dominates. The particles of iron ore and synthetic Fe2O3/MgAl2O4 have better stability than that of pure Fe2O3 when the reaction temperature is limited to lower than 1223 K. These preliminary results suggest that iron-based mixed oxygen carrier particles are potential to be used in methane chemical looping process, but the reactivity of the iron ore needs to be increased.

  15. Advanced exergoenvironmental analysis of a near-zero emission power plant with chemical looping combustion.

    Science.gov (United States)

    Petrakopoulou, Fontina; Tsatsaronis, George; Morosuk, Tatiana

    2012-03-06

    Carbon capture and storage (CCS) from power plants can be used to mitigate CO(2) emissions from the combustion of fossil fuels. However, CCS technologies are energy intensive, decreasing the operating efficiency of a plant and increasing its costs. Recently developed advanced exergy-based analyses can uncover the potential for improvement of complex energy conversion systems, as well as qualify and quantify plant component interactions. In this paper, an advanced exergoenvironmental analysis is used for the first time as means to evaluate an oxy-fuel power plant with CO(2) capture. The environmental impacts of each component are split into avoidable/unavoidable and endogenous/exogenous parts. In an effort to minimize the environmental impact of the plant operation, we focus on the avoidable part of the impact (which is also split into endogenous and exogenous parts) and we seek ways to decrease it. The results of the advanced exergoenvironmental analysis show that the majority of the environmental impact related to the exergy destruction of individual components is unavoidable and endogenous. Thus, the improvement potential is rather limited, and the interactions of the components are of lower importance. The environmental impact of construction of the components is found to be significantly lower than that associated with their operation; therefore, our suggestions for improvement focus on measures concerning the reduction of exergy destruction and pollutant formation.

  16. Analysis of Combined Cycle Power Plants with Chemical Looping Reforming of Natural Gas and Pre-Combustion CO2 Capture

    Directory of Open Access Journals (Sweden)

    Shareq Mohd Nazir

    2018-01-01

    Full Text Available In this paper, a gas-fired combined cycle power plant subjected to a pre-combustion CO2 capture method has been analysed under different design conditions and different heat integration options. The power plant configuration includes the chemical looping reforming (CLR of natural gas (NG, water gas shift (WGS process, CO2 capture and compression, and a hydrogen fuelled combined cycle to produce power. The process is denoted as a CLR-CC process. One of the main parameters that affects the performance of the process is the pressure for the CLR. The process is analysed at different design pressures for the CLR, i.e., 5, 10, 15, 18, 25 and 30 bar. It is observed that the net electrical efficiency increases with an increase in the design pressure in the CLR. Secondly, the type of steam generated from the cooling of process streams also effects the net electrical efficiency of the process. Out of the five different cases including the base case presented in this study, it is observed that the net electrical efficiency of CLR-CCs can be improved to 46.5% (lower heating value of NG basis by producing high-pressure steam through heat recovery from the pre-combustion process streams and sending it to the Heat Recovery Steam Generator in the power plant.

  17. Rotary Bed Reactor for Chemical-Looping Combustion with Carbon Capture. Part 1: Reactor Design and Model Development

    KAUST Repository

    Zhao, Zhenlong

    2013-01-17

    Chemical-looping combustion (CLC) is a novel and promising technology for power generation with inherent CO2 capture. Currently, almost all of the research has been focused on developing CLC-based interconnected fluidized-bed reactors. In this two-part series, a new rotary reactor concept for gas-fueled CLC is proposed and analyzed. In part 1, the detailed configuration of the rotary reactor is described. In the reactor, a solid wheel rotates between the fuel and air streams at the reactor inlet and exit. Two purging sectors are used to avoid the mixing between the fuel stream and the air stream. The rotary wheel consists of a large number of channels with copper oxide coated on the inner surface of the channels. The support material is boron nitride, which has high specific heat and thermal conductivity. Gas flows through the reactor at elevated pressure, and it is heated to a high temperature by fuel combustion. Typical design parameters for a thermal capacity of 1 MW have been proposed, and a simplified model is developed to predict the performances of the reactor. The potential drawbacks of the rotary reactor are also discussed. © 2012 American Chemical Society.

  18. Chemical looping reactor system design double loop circulating fluidized bed (DLCFB)

    Energy Technology Data Exchange (ETDEWEB)

    Bischi, Aldo

    2012-05-15

    Chemical looping combustion (CLC) is continuously gaining more importance among the carbon capture and storage (CCS) technologies. It is an unmixed combustion process which takes place in two steps. An effective way to realize CLC is to use two interconnected fluidized beds and a metallic powder circulating among them, acting as oxygen carrier. The metallic powder oxidizes at high temperature in one of the two reactors, the air reactor (AR). It reacts in a highly exothermic reaction with the oxygen of the injected fluidising air. Afterwards the particles are sent to the other reactor where the fuel is injected, the fuel reactor (FR). There, they transport heat and oxygen necessary for the reaction with the injected fuel to take place. At high temperatures, the particle's oxygen reacts with the fuel producing Co2 and steam, and the particles are ready to start the loop again. The overall reaction, the sum of the enthalpy changes of the oxygen carrier oxidation and reduction reactions, is the same as for the conventional combustion. Two are the key features, which make CLC promising both for costs and capture efficiency. First, the high inherent irreversibility of the conventional combustion is avoided because the energy is utilized stepwise. Second, the Co2 is intrinsically separated within the process; so there is in principle no need either of extra carbon capture devices or of expensive air separation units to produce oxygen for oxy-combustion. A lot of effort is taking place worldwide on the development of new chemical looping oxygen carrier particles, reactor systems and processes. The current work is focused on the reactor system: a new design is presented, for the construction of an atmospheric 150kWth prototype working with gaseous fuel and possibly with inexpensive oxygen carriers derived from industrial by-products or natural minerals. It consists of two circulating fluidized beds capable to operate in fast fluidization regime; this will increase the

  19. Study on Reaction Characteristics of Chemical-Looping Combustion between Maize Stalk and High Index Facet Iron Oxide

    Directory of Open Access Journals (Sweden)

    Wu Qin

    2016-08-01

    Full Text Available In this work, experiments were performed to investigate the activity and regeneration ability of iron-based oxygen carrier with high index facet (104 during chemical looping combustion (CLC, suggesting that morphological control of the oxygen carrier is very rewarding. Fe2O3(104 supported on Al2O3 was synthesized by a morphology controlled method to undertake maize stalk CLC experiments. Compared with the referenced Fe2O3/Al2O3 prepared by the impregnation method, Fe2O3(104/Al2O3 presents better reactivity, showing higher fuel conversion rate and CO2 concentration in gaseous products. Further, structural characterizations, including X-ray diffraction (XRD, scanning electron microscopy (SEM (LEO-1450 and Brunauer-Emmett-Teller (BET analysis, and multi-cycles CLC reactions were performed to verify the good regeneration and stability of the Fe2O3(104/Al2O3. The findings indicate that the Fe2O3(104/Al2O3 is efficient when used for CLC of maize stalk.

  20. Thermogravimetric Analysis of Modified Hematite by Methane (CH{sub 4}) for Chemical-Looping Combustion: A Global Kinetics Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Monazam, Esmail R; Breault, Ronald W; Siriwardane, Ranjani; Miller, Duane D

    2013-10-01

    Iron oxide (Fe{sub 2}O{sub 3}) or in its natural form (hematite) is a potential material to capture CO{sub 2} through the chemical-looping combustion (CLC) process. It is known that magnesium (Mg) is an effective methyl cleaving catalyst and as such it has been combined with hematite to assess any possible enhancement to the kinetic rate for the reduction of Fe{sub 2}O{sub 3} with methane. Therefore, in order to evaluate its effectiveness as a hematite additive, the behaviors of Mg-modified hematite samples (hematite –5% Mg(OH){sub 2}) have been analyzed with regard to assessing any enhancement to the kinetic rate process. The Mg-modified hematite was prepared by hydrothermal synthesis. The reactivity experiments were conducted in a thermogravimetric analyzer (TGA) using continuous stream of CH{sub 4} (5, 10, and 20%) at temperatures ranging from 700 to 825 {degrees}C over ten reduction cycles. The mass spectroscopy analysis of product gas indicated the presence of CO{sub 2}, H{sub 2}O, H{sub 2} and CO in the gaseous product. The kinetic data at reduction step obtained by isothermal experiments could be well fitted by two parallel rate equations. The modified hematite samples showed higher reactivity as compared to unmodified hematite samples during reduction at all investigated temperatures.

  1. Highly Efficient Oxygen-Storage Material with Intrinsic Coke Resistance for Chemical Looping Combustion-Based CO2 Capture.

    Science.gov (United States)

    Imtiaz, Qasim; Kurlov, Alexey; Rupp, Jennifer Lilia Marguerite; Müller, Christoph Rüdiger

    2015-06-22

    Chemical looping combustion (CLC) and chemical looping with oxygen uncoupling (CLOU) are emerging thermochemical CO2 capture cycles that allow the capture of CO2 with a small energy penalty. Here, the development of suitable oxygen carrier materials is a key aspect to transfer these promising concepts to practical installations. CuO is an attractive material for CLC and CLOU because of its high oxygen-storage capacity (20 wt %), fast reaction kinetics, and high equilibrium partial pressure of oxygen at typical operating temperatures (850-1000 °C). However, despite its promising characteristics, its low Tammann temperature requires the development of new strategies to phase-stabilize CuO-based oxygen carriers. In this work, we report a strategy based on stabilization by co-precipitated ceria (CeO2-x ), which allowed us to increase the oxygen capacity, coke resistance, and redox stability of CuO-based oxygen carriers substantially. The performance of the new oxygen carriers was evaluated in detail and compared to the current state-of-the-art materials, that is, Al2 O3 -stabilized CuO with similar CuO loadings. We also demonstrate that the higher intrinsic oxygen uptake, release, and mobility in CeO2-x -stabilized CuO leads to a three times higher carbon deposition resistance compared to that of Al2 O3 -stabilized CuO. Moreover, we report a high cyclic stability without phase intermixing for CeO2-x -supported CuO. This was accompanied by a lower reduction temperature compared to state-of-the-art Al2 O3 -supported CuO. As a result of its high resistance towards carbon deposition and fast oxygen uncoupling kinetics, CeO2-x -stabilized CuO is identified as a very promising material for CLC- and CLOU-based CO2 capture architectures. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Investigation of coal fueled chemical looping combustion using Fe3O4 as oxygen carrier: Influence of variables

    Science.gov (United States)

    Sun, Xiaoyan; Xiang, Wenguo; Wang, Sha; Tian, Wendong; Xu, Xiang; Xu, Yanji; Xiao, Yunhan

    2010-06-01

    Chemical-looping combustion (CLC) is a novel combustion technique with inherent CO2 separation. Magnetite (Fe3O4) was selected as the oxygen carrier. Shenhua coal (Inner Mongolia, China), straw coke and natural coke were used as fuels for this study. Influences of operation temperatures, coal to Fe3O4 mass ratios, and different kinds of fuels on the reduction characteristics of the oxygen carrier were investigated using an atmosphere thermogravimetric analyzer (TGA). Scanning electron microscopy (SEM) was used to analyse the characteristic of the solid residues. Experimental results shown that the reaction between the coal and the oxygen carrier become strong at a temperature of higher than 800°C. As the operation temperature rises, the reduction conversion rate increases. At the temperatures of 850°C, 900°C, and 950°C, the reduction conversion rates were 37.1%, 46.5%, and 54.1% respectively. However, SEM images show that at the temperature of higher than 950°C, the iron oxides become melted and sintered. The possible operation temperature should be kept around 900°C. When the mass ratios of coal to Fe3O4 were 5/95, 10/90, 15/85, and 20/80, the reduction conversion rates were 29.5%, 40.8%, 46.5%, and 46.6% respectively. With the increase of coal, the conversion rate goes up. But there exist an optimal ratio around 15/85. Comparisons based on different kinds of fuels show that the solid fuel with a higher volatile and a more developed pore structure is conducive to the reduction reactivity of the oxygen carrier.

  3. Rotary Bed Reactor for Chemical-Looping Combustion with Carbon Capture. Part 2: Base Case and Sensitivity Analysis

    KAUST Repository

    Zhao, Zhenlong

    2013-01-17

    Part 1 (10.1021/ef3014103) of this series describes a new rotary reactor for gas-fueled chemical-looping combustion (CLC), in which, a solid wheel with microchannels rotates between the reducing and oxidizing streams. The oxygen carrier (OC) coated on the surfaces of the channels periodically adsorbs oxygen from air and releases it to oxidize the fuel. A one-dimensional model is also developed in part 1 (10.1021/ef3014103). This paper presents the simulation results based on the base-case design parameters. The results indicate that both the fuel conversion efficiency and the carbon separation efficiency are close to unity. Because of the relatively low reduction rate of copper oxide, fuel conversion occurs gradually from the inlet to the exit. A total of 99.9% of the fuel is converted within 75% of the channel, leading to 25% redundant length near the exit, to ensure robustness. In the air sector, the OC is rapidly regenerated while consuming a large amount of oxygen from air. Velocity fluctuations are observed during the transition between sectors because of the complete reactions of OCs. The gas temperature increases monotonically from 823 to 1315 K, which is mainly determined by the solid temperature, whose variations with time are limited within 20 K. The overall energy in the solid phase is balanced between the reaction heat release, conduction, and convective cooling. In the sensitivity analysis, important input parameters are identified and varied around their base-case values. The resulting changes in the model-predicted performance revealed that the most important parameters are the reduction kinetics, the operating pressure, and the feed stream temperatures. © 2012 American Chemical Society.

  4. Thermodynamic Analysis of an Electrochemically Driven Chemical Looping Heat Pump

    OpenAIRE

    James, Nelson A.; Braun, James E.; Groll, Eckhard A.; Horton, W. Travis

    2016-01-01

    Electrochemical cells have been widely explored for their use in high efficiency energy systems. In this paper a novel heat pump cycle is proposed which utilizes chemical looping driven by electrochemical cells. Chemical looping is a method that has been applied to various applications such as combustion and air separation. It consists of the cycling of a substance between different chemical compositions in order to produce a desired effect. When the chemical composition of a fluid changes, v...

  5. Sulfur evolution in chemical looping combustion of coal with MnFe2O4 oxygen carrier.

    Science.gov (United States)

    Wang, Baowen; Gao, Chuchang; Wang, Weishu; Zhao, Haibo; Zheng, Chuguang

    2014-05-01

    Chemical looping combustion (CLC) of coal has gained increasing attention as a novel combustion technology for its advantages in CO2 capture. Sulfur evolution from coal causes great harm from either the CLC operational or environmental perspective. In this research, a combined MnFe2O4 oxygen carrier (OC) was synthesized and its reaction with a typical Chinese high sulfur coal, Liuzhi (LZ) bituminous coal, was performed in a thermogravimetric analyzer (TGA)-Fourier transform infrared (FT-IR) spectrometer. Evolution of sulfur species during reaction of LZ coal with MnFe2O4 OC was systematically investigated through experimental means combined with thermodynamic simulation. TGA-FTIR analysis of the LZ reaction with MnFe2O4 indicated MnFe2O4 exhibited the desired superior reactivity compared to the single reference oxides Mn3O4 or Fe2O3, and SO2 produced was mainly related to oxidization of H2S by MnFe2O4. Experimental analysis of the LZ coal reaction with MnFe2O4, including X-ray diffraction and X-ray photoelectron spectroscopy analysis, verified that the main reduced counterparts of MnFe2O4 were Fe3O4 and MnO, in good agreement with the related thermodynamic simulation. The obtained MnO was beneficial to stabilize the reduced MnFe2O4 and avoid serious sintering, although the oxygen in MnO was not fully utilized. Meanwhile, most sulfur present in LZ coal was converted to solid MnS during LZ reaction with MnFe2O4, which was further oxidized to MnSO4. Finally, the formation of both MnS and such manganese silicates as Mn2SiO4 and MnSiO3 should be addressed to ensure the full regeneration of the reduced MnFe2O4. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  6. Kinetics of the reduction of hematite (Fe{sub 2}O{sub 3}) by methane (CH{sub 4}) during chemical looping combustion: A global mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Monazam, Esmail R; Breault, Ronald W; Siriwardane, Ranjani; Richards, George; Carpenter, Stephen

    2013-10-01

    Chemical-looping combustion (CLC) has emerged as a promising technology for fossil fuel combustion which produces a sequestration ready concentrated CO{sub 2} stream in power production. A CLC system is composed with two reactors, an air and a fuel reactor. An oxygen carrier such as hematite (94%Fe{sub 2}O{sub 3}) circulates between the reactors, which transfers the oxygen necessary for the fuel combustion from the air to the fuel. An important issue for the CLC process is the selection of metal oxide as oxygen carrier, since it must retain its reactivity through many cycles. The primary objective of this work is to develop a global mechanism with respective kinetics rate parameters such that CFD simulations can be performed for large systems. In this study, thermogravimetric analysis (TGA) of the reduction of hematite (Fe{sub 2}O{sub 3}) in a continuous stream of CH{sub 4} (15, 20, and 35%) was conducted at temperatures ranging from 700 to 825{degrees}C over ten reduction cycles. The mass spectroscopy analysis of product gas indicated the presence of CO{sub 2} and H{sub 2}O at the early stage of reaction and H{sub 2} and CO at the final stage of reactions. A kinetic model based on two parallel reactions, 1) first-order irreversible rate kinetics and 2) Avrami equation describing nucleation and growth processes, was applied to the reduction data. It was found, that the reaction rates for both reactions increase with, both, temperature and the methane concentration in inlet gas.

  7. Synergetic effect of ZrO2 on the oxidation-reduction reaction of Fe2O3 during chemical looping combustion

    Science.gov (United States)

    Tan, Qinliang; Qin, Wu; Chen, Qiuluan; Dong, Changqing; Li, Wenyan; Yang, Yongping

    2012-10-01

    Fe2O3/ZrO2 model oxygen carrier is constructed at atomic-level precision under ultra-high-vacuum conditions. Based on density functional theory calculations and molecular dynamical simulations, structure and energy analysis suggests that the complex Fe2O3/ZrO2 is stable and more chemically active than the pure Fe2O3, ZrO2 promotes the adsorption of CO, which is chemisorption rather than physisorption on the pure Fe2O3 surface. Interface electronic interaction of Fe2O3/ZrO2 makes Fe2O3 positive to accept electron from CO easily and hence promoting the chemisorption of CO and the formation of carbonate species, while such electronic interaction makes it relatively more difficult in oxidizing Fe2O2 supported on ZrO2. However, all reaction barrier energies are small enough for Fe2O2 oxidation to happen under high temperature in the CLC system. Both CO oxidation by Fe2O3/ZrO2 related to the fuel reactor in the chemical looping combustion (CLC) system and Fe2O2/ZrO2 oxidation by O2 related to the air reactor in CLC system illustrate the synergetic effect of ZrO2 on the CO oxidation and Fe2O2 oxidation.

  8. Chemical Looping Combustion with Different Types of Liquid Fuels Combustion en boucle chimique avec différentes charges liquides

    Directory of Open Access Journals (Sweden)

    Hoteit A.

    2011-02-01

    Full Text Available CLC is a new promising combustion process for CO2 capture with less or even no energy penalty compared to other processes. Up to now, most of the work performed on CLC was conducted with gaseous or solid fuels, using methane and coal and/or pet coke. Liquid fuels such as heavy fuels resulting from oil distillation or conversion may also be interesting feedstocks to consider. However, liquid fuels are challenging feedstock to deal with in fluidized beds. The objective of the present work is therefore to investigate the feasibility of liquid feed injection and contact with oxygen carrier in CLC conditions in order to conduct partial or complete combustion of hydrocarbons. A batch experimental fluidized bed set-up was developed to contact alternatively oxygen carrier with liquid fuels or air. The 20 mm i.d. fluidized bed reactor was filled up with 45 g of NiAl0.44O1.67 and pulses of 1-2 g of liquid were injected in the bed at high temperatures up to 950˚C. Different feedstocks have been injected, from dodecane to heavy fuel oils No.2. Results show that, during the reduction period, it is possible to convert all the fuel injected and there is no coke remaining on particles at the end of the reduction step. Depending upon oxygen available in the bed, either full combustion or partial combustion can be achieved. Similar results were found with different liquid feeds, despite their different composition and properties. Le CLC est un nouveau concept prometteur appliqué à la combustion qui permet le captage de CO en minimisant la pénalité énergétique liée au captage. Jusqu’à présent, l’essentiel des travaux de recherche dans le domaine du CLC concerne les charges gazeuses (méthane et solides (charbon et coke. Les charges liquides, et particulièrement les résidus pétroliers, sont des charges également intéressantes à considérer a priori. La mise en oeuvre de ces charges en lit fluidisé est cependant délicate. L’objet de ce

  9. Chemical Looping Technology: Oxygen Carrier Characteristics.

    Science.gov (United States)

    Luo, Siwei; Zeng, Liang; Fan, Liang-Shih

    2015-01-01

    Chemical looping processes are characterized as promising carbonaceous fuel conversion technologies with the advantages of manageable CO2 capture and high energy conversion efficiency. Depending on the chemical looping reaction products generated, chemical looping technologies generally can be grouped into two types: chemical looping full oxidation (CLFO) and chemical looping partial oxidation (CLPO). In CLFO, carbonaceous fuels are fully oxidized to CO2 and H2O, as typically represented by chemical looping combustion with electricity as the primary product. In CLPO, however, carbonaceous fuels are partially oxidized, as typically represented by chemical looping gasification with syngas or hydrogen as the primary product. Both CLFO and CLPO share similar operational features; however, the optimum process configurations and the specific oxygen carriers used between them can vary significantly. Progress in both CLFO and CLPO is reviewed and analyzed with specific focus on oxygen carrier developments that characterize these technologies.

  10. Chemical Looping Combustion of Solid Fuels in a Laboratory Fluidized-bed Reactor Combustion de charges solides avec la boucle chimique dans un lit fluidisé de laboratoire

    Directory of Open Access Journals (Sweden)

    Leion H.

    2011-02-01

    Full Text Available When using solid fuel in a chemical looping system, the char fraction of the fuel needs to be gasified before syngas react with the oxygen carrier. This can be done inside the fuel reactor with fuel and oxygen carriers well mixed, and, since this gasification is comparably slow, this will be the time limiting step of such a system. An option is to use an oxygen carrier that is able to release gas-phase oxygen which can react with the fuel by normal combustion giving a significantly faster overall fuel conversion. This last option is generally referred to as Chemical Looping combustion with Oxygen Un-coupling (CLOU. In this work, an overview is given of parameters that affect the fuel conversion in laboratory CLC and CLOU experiments. The main factor determining the fuel conversion, in both CLC and CLOU, is the fuel itself. High-volatile fuels are generally more rapidly converted than low volatile fuels. This difference in fuel conversion rate is more pronounced in CLC than in CLOU. However, the fuel conversion is also, both for CLC and CLOU, increased by increasing temperature. Increased steam and SO2 fraction in the surrounding gas will also enhance the fuel conversion in CLC. CO2 gasification in CLC appears to be very slow in comparison to steam gasification. H2 can inhibit fuel gasification in CLC whereas CO did not seem to have any effect. Possible deactivation of oxygen carriers due to SO2 or ash also has to be considered. Lorsque l’on utilise des combustibles solides dans la boucle chimique (CLC pour Chemical Looping Combustion, il est nécessaire de gazéifier le char avant de faire la combustion du gaz de synthèse au contact du transporteur d’oxygène. Ces réactions peuvent s’effectuer dans le réacteur fuel, dans lequel le combustible et le transporteur d’oxygène sont bien mélangés. Cependant, la gazéification du charbon est lente et reste l’étape limitante du processus de combustion dans ces conditions. Une alternative

  11. Reduction and Oxidation Kinetics of a CaMn0.9Mg0.1O3-delta Oxygen Carrier for Chemical-Looping Combustion

    OpenAIRE

    Diego Poza, Luis F. de; Abad Secades, Alberto; Caballero Flores, Arturo; Gayán Sanz, Pilar; García-Labiano, Francisco; Adánez Elorza, Juan

    2014-01-01

    The objective of this study was to establish the reaction kinetics involved in redox cycles of the CaMn0.9Mg0.1O3−δ material to be used as an oxygen carrier in the chemical-looping-combustion process. The oxygen-transport capacity and reactivity of this material during consecutive reduction and oxidation steps with gaseous compounds (CH4, H2, CO, and O2) were studied in a thermogravimetric analysis apparatus. The oxygen uncoupling properties of this material were also analyzed. It was found t...

  12. Theoretical study of oxidation-reduction reaction of Fe2O3 supported on MgO during chemical looping combustion

    Science.gov (United States)

    Qin, Wu; Chen, Qiuluan; Wang, Yang; Dong, Changqing; Zhang, Junjiao; Li, Wenyan; Yang, Yongping

    2013-02-01

    We applied density-functional theory (DFT) in periodic system to investigate the two reactions (CO + Fe2O3/MgO → CO2 + Fe2O2/MgO, O2 + Fe2O2/MgO → O + Fe2O3/MgO) in chemical looping combustion system. While Fe2O3 was supported on MgO(1 0 0) surface Fe2O3 gathered together to form a cluster shape on MgO(1 0 0), denoted as Fe2O3/MgO, where the Fe2O3 was activated by MgO(1 0 0). Then CO interacted with Fe2O3/MgO and carbonate generated during a stepwise reaction with the calculated maximum barrier energy of 0.95 eV, far less than that of the reaction between CO and the pure Fe2O3 cluster (2.59 eV). CO was oxidized by Fe2O3/MgO and then Fe2O3/MgO transformed into the reduced state Fe2O2/MgO, corresponding to the reaction in the fuel reactor in the CLC system. Then the breaking of the adsorbed O2 molecule on Fe2O2/MgO made an O atom bind to a Fe site with the barrier energy of 0. 20 eV, which played as the key step for the oxidizing of Fe2O2/MgO by O2 into Fe2O3/MgO, corresponding to the reaction in the air reactor in the CLC system.

  13. Theoretical study of stability and reaction mechanism of CuO supported on ZrO2 during chemical looping combustion

    Science.gov (United States)

    Wang, Minjun; Liu, Jing; Shen, Fenghua; Cheng, Hao; Dai, Jinxin; Long, Yan

    2016-03-01

    The addition of inert support is important for the Cu-based oxygen carrier used in chemical looping combustion (CLC). The effects of the ZrO2 support on the stability and reactivity of Cu-based oxygen carrier were investigated using the density functional theory (DFT). First, the sintering inhibition mechanism of ZrO2 that support active CuO was investigated. The optimized Cu4O4/ZrO2 structure showed a strong interaction occurred between the Cu4O4 cluster and ZrO2(1 0 1) surface. The interaction prevented the migration and agglomeration of CuO. Next, the adsorption of CO on Cu4O4/ZrO2 and the mechanism of the CuO/ZrO2 reduction by CO were studied. CO mainly chemisorbed on the Cu site and ZrO2 acted as an electron donor in the adsorption system. The energy barrier of CuO/ZrO2 reduction by CO (0.79 eV) was much lower than that of the pure CuO cluster (1.44 eV), indicating that ZrO2 had a positive effect on CuO/ZrO2 reduction by CO. After CO was oxidized in the fuel reactor, the CuO was reduced into Cu. The adsorption of O2 on Cu2/ZrO2 and the most likely pathway of Cu2/ZrO2 oxidation by O2 were investigated. The adsorption of O2 was found a strong chemisorption behavior. The energy barriers were low enough for the Cu-based oxygen carrier oxidation reaction.

  14. The synergetic effect of metal oxide support on Fe{sub 2}O{sub 3} for chemical looping combustion: A theoretical study

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Wu, E-mail: qinwugx@126.com; Wang, Yang; Dong, Changqing, E-mail: cqdong1@163.com; Zhang, Junjiao; Chen, Qiuluan; Yang, Yongping

    2013-10-01

    This study deals with the synergetic effect of Al{sub 2}O{sub 3} on Fe{sub 2}O{sub 3} for chemical-looping combustion (CLC) of CO, in comparison with the synergetic effects of ZrO{sub 2} and MgO reported in our previous works. Property analysis of Fe{sub 2}O{sub 3}/Al{sub 2}O{sub 3} shows that new bonds form cross the interface making Fe{sub 2}O{sub 3} less prone to agglomerate on Al{sub 2}O{sub 3}, and 0.129 e transfers from Al{sub 2}O{sub 3} to Fe{sub 2}O{sub 3} to activate the electronic state of Fe{sub 2}O{sub 3}. Al{sub 2}O{sub 3} [ZrO{sub 2} and MgO] favors the thermal stability of Fe{sub 2}O{sub 3} by preventing the phase transformation, markedly regulates charge populations on the O-Fe bonds and their overlaps and hence tunes the redox properties of Fe{sub 2}O{sub 3}. The reaction mechanism analysis demonstrates that Al{sub 2}O{sub 3} [ZrO{sub 2} and MgO] activates Fe{sub 2}O{sub 3} for oxidizing CO into CO{sub 2} (accompanied by the reduction of Fe{sub 2}O{sub 3}) in the fuel reactor, which decrease the height of barrier energy (E{sub a}), and the E{sub a} follows clearly Fe{sub 2}O{sub 3} > Fe{sub 2}O{sub 3}/Al{sub 2}O{sub 3} > Fe{sub 2}O{sub 3}/MgO > Fe{sub 2}O{sub 3}/ZrO{sub 2}. However, these supports usually increase the E{sub a} for oxidizing Fe{sub 2}O{sub 2} into Fe{sub 2}O{sub 3} by O{sub 2} in the air reactor, and the E{sub a} follows clearly Fe{sub 2}O{sub 3}/ZrO{sub 2} > Fe{sub 2}O{sub 3}/Al{sub 2}O{sub 3} > Fe{sub 2}O{sub 3}/MgO > Fe{sub 2}O{sub 3}. It is argued that different supports could be applied to a given CLC system of different thermodynamic properties.

  15. Theoretical study of stability and reaction mechanism of CuO supported on ZrO{sub 2} during chemical looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Minjun; Liu, Jing, E-mail: liujing27@mail.hust.edu.cn; Shen, Fenghua; Cheng, Hao; Dai, Jinxin; Long, Yan

    2016-03-30

    Graphical abstract: - Highlights: • The stability and reaction mechanism of CuO supported on ZrO{sub 2} were studied by DFT. • ZrO{sub 2} provides a high resistance to CuO sintering. • ZrO{sub 2} promotes the activity of CuO for CO oxidation in fuel reactor. • The energy barriers are low enough for CuO/ZrO{sub 2} oxidation reaction in air reactor. - Abstract: The addition of inert support is important for the Cu-based oxygen carrier used in chemical looping combustion (CLC). The effects of the ZrO{sub 2} support on the stability and reactivity of Cu-based oxygen carrier were investigated using the density functional theory (DFT). First, the sintering inhibition mechanism of ZrO{sub 2} that support active CuO was investigated. The optimized Cu{sub 4}O{sub 4}/ZrO{sub 2} structure showed a strong interaction occurred between the Cu{sub 4}O{sub 4} cluster and ZrO{sub 2}(1 0 1) surface. The interaction prevented the migration and agglomeration of CuO. Next, the adsorption of CO on Cu{sub 4}O{sub 4}/ZrO{sub 2} and the mechanism of the CuO/ZrO{sub 2} reduction by CO were studied. CO mainly chemisorbed on the Cu site and ZrO{sub 2} acted as an electron donor in the adsorption system. The energy barrier of CuO/ZrO{sub 2} reduction by CO (0.79 eV) was much lower than that of the pure CuO cluster (1.44 eV), indicating that ZrO{sub 2} had a positive effect on CuO/ZrO{sub 2} reduction by CO. After CO was oxidized in the fuel reactor, the CuO was reduced into Cu. The adsorption of O{sub 2} on Cu{sub 2}/ZrO{sub 2} and the most likely pathway of Cu{sub 2}/ZrO{sub 2} oxidation by O{sub 2} were investigated. The adsorption of O{sub 2} was found a strong chemisorption behavior. The energy barriers were low enough for the Cu-based oxygen carrier oxidation reaction.

  16. Hydrogen production with CO 2 capture by coupling steam reforming of methane and chemical-looping combustion: Use of an iron-based waste product as oxygen carrier burning a PSA tail gas

    Science.gov (United States)

    Ortiz, María; Gayán, Pilar; de Diego, Luis F.; García-Labiano, Francisco; Abad, Alberto; Pans, Miguel A.; Adánez, Juan

    In this work it is analyzed the performance of an iron waste material as oxygen carrier for a chemical-looping combustion (CLC) system. CLC is a novel combustion technology with the benefit of inherent CO 2 separation that can be used as a source of energy for the methane steam reforming process (SR). The tail gas from the PSA unit is used as fuel in the CLC system. The oxygen carrier behaviour with respect to gas combustion was evaluated in a continuous 500 W th CLC prototype using a simulated PSA off-gas stream as fuel. Methane or syngas as fuel were also studied for comparison purposes. The oxygen carrier showed enough high oxygen transport capacity and reactivity to fully convert syngas at 880 °C. However, lower conversion of the fuel was observed with methane containing fuels. An estimated solids inventory of 1600 kg MW th -1 would be necessary to fully convert the PSA off-gas to CO 2 and H 2O. An important positive effect of the oxygen carrier-to-fuel ratio up to 1.5 and the reactor temperature on the combustion efficiency was found. A characterization of the calcined and after-used particles was carried out showing that this iron-based material can be used as oxygen carrier in a CLC plant since particles maintain their properties (reactivity, no agglomeration, high durability, etc.) after more than 111 h of continuous operation.

  17. Synthesis and characterization of sintering-resistant silica-encapsulated Fe3O4 magnetic nanoparticles active for oxidation and chemical looping combustion

    Science.gov (United States)

    Park, Jung-Nam; Zhang, Peng; Hu, Yong-Sheng; McFarland, Eric W.

    2010-06-01

    A nanocomposite catalyst composed of ferromagnetic magnetite cores (15.5 ± 2.0 nm) and silica shells with a thickness of 4.5 ± 1.0 nm (Fe3O4@SiO2) was prepared by a two-step microemulsion-based synthesis. X-ray photoelectron spectroscopy and Raman spectroscopy after oxidation support the presence of a stable Fe3O4 core and a surface phase of γ-Fe2O3. The nanocomposite structure exhibited 100% conversion of CO in oxygen at a residence time of 0.1 s at 310 °C. When pre-oxidized, the Fe3O4@SiO2 catalyst is shown to be a suitable solid oxygen carrier for chemical looping combustion of methane at 700 °C. The nanocomposites retain their magnetism following the reaction which provides the potential for use of magnetic separation and capture in moving bed reactor applications. The core magnetite within the silica shell is resistant to sintering and a bulk phase transition to temperatures as high as 700 °C. These catalysts can be of use in applications of high temperature applications where catalyst recovery by magnetic separation may be required.

  18. Kinetics of Oxidation of a Reduced Form of the Cu-Based Oxygen-Carrier for Use in Chemical-Looping Combustion

    Science.gov (United States)

    Chuang, S. Y.; Dennis, J. S.; Hayhurst, A. N.; Scott, S. A.

    A co-precipitated mixture of CuO and Al2O3 is a good oxygen-carrier for chemical-looping combustion. The kinetics of regeneration of this reduced oxygen-carrier (355 - 500 urn) were measured from 300 to 750°C when reacting it with O2. Care was taken to ensure these measurements were not affected by interphase mass transfer. Efforts were also made to minimise sampling problems by using a rapid-response mass spectrometer for reactions lasting for 45 s or less; otherwise, a paramagnetic analyser for O2 was used, since the mass spectrometer drifted with time. The order of reaction with respect to O2 was found to be ˜ unity at 300 to 750°C. Below 600°C, the reduced oxygen-carrier was incompletely oxidised to a mixture of CU2O and Al2O3. Above 600°C, regeneration was completely to CuO and Al2O3 and was controlled to a considerable extent by external mass transfer. At these higher temperatures, regeneration involved a shrinking core mechanism and the two consecutive steps: 2Cu + 1/2O_2 to Cu_2 O, Cu_2 O + 1/2O_2 to 2CuO. The activation energies and pre-exponential factors for both reactions were measured from initial rates. The kinetics in the first cycle of operations were found to be similar to those in the subsequent cycles.

  19. The Effects of Thermal Treatment and Steam Addition on Integrated CuO/CaO Chemical Looping Combustion for CO2 Capture

    Directory of Open Access Journals (Sweden)

    Alvaro Recio

    2016-04-01

    Full Text Available The combination of Chemical Looping Combustion (CLC with Calcium Looping (CaL using integrated pellets is an alternative CO2 capture process to the current amine-based sorbent processes, but the pellets lose sorption capacity over time. In this paper, the deactivation behavior of CaO, CuO and CuO/CaO integrated pellets used for multiple (16–20 cycles in a thermogravimetric analyzer was studied. The impact of thermal treatment and the presence of steam on the deactivation were also investigated. Nitrogen physisorption and scanning electron microscopy/energy-dispersive X-ray analysis were used to characterize the pellets. The analysis revealed significant migration of the copper to the surface of the composite pellets, which likely suppressed carbonation capacity by reducing the accessibility of the CaO. While thermal pre-treatment and steam addition enhanced the performance of the base CaO pellets, the former led to cracks in the pellets. In contrast, thermal pretreatment of the CuO/CaO composite pellets resulted in worse CLC and CaL performance.

  20. Calcium and chemical looping technology for power generation and carbon dioxide (CO2) capture solid oxygen- and CO2-carriers

    CERN Document Server

    Fennell, Paul

    2015-01-01

    Calcium and Chemical Looping Technology for Power Generation and Carbon Dioxide (CO2) Capture reviews the fundamental principles, systems, oxygen carriers, and carbon dioxide carriers relevant to chemical looping and combustion. Chapters review the market development, economics, and deployment of these systems, also providing detailed information on the variety of materials and processes that will help to shape the future of CO2 capture ready power plants. Reviews the fundamental principles, systems, oxygen carriers, and carbon dioxide carriers relevant to calcium and chemical loopingProvi

  1. Feasibility study of sulfates as oxygen carriers for chemical looping processes

    Directory of Open Access Journals (Sweden)

    Ganesh Kale

    2012-12-01

    Full Text Available The operational feasibility temperature range of chemical looping combustion (CLC and chemical looping reforming (CLR of the fuels methane, propane, iso-octane and ethanol was explored using the common sulphates

  2. Design of a rotary reactor for chemical-looping combustion. Part 2: Comparison of copper-, nickel-, and iron-based oxygen carriers

    KAUST Repository

    Zhao, Zhenlong

    2014-04-01

    Chemical-looping combustion (CLC) is a novel and promising option for several applications including carbon capture (CC), fuel reforming, H 2 generation, etc. Previous studies demonstrated the feasibility of performing CLC in a novel rotary design with micro-channel structures. Part 1 of this series studied the fundamentals of the reactor design and proposed a comprehensive design procedure, enabling a systematic methodology of designing and evaluating the rotary CLC reactor with different OCs and operating conditions. This paper presents the application of the methodology to the designs with three commonly used OCs, i.e., copper, nickel, and iron. The physical properties and the reactivities of the three OCs are compared at operating conditions suitable for the rotary CLC. Nickel has the highest reduction rate, but relatively slow oxidation reactivity while the iron reduction rate is most sensitive to the fuel concentration. The design parameters and the operating conditions for the three OCs are selected, following the strategies proposed in Part 1, and the performances are evaluated using a one-dimensional plug-flow model developed previously. The simulations show that for all OCs, complete fuel conversion and high carbon separation efficiency can be achieved at periodic stationary state with reasonable operational stabilities. The nickel-based design includes the smallest dimensions because of its fast reduction rate. The operation of nickel case is mainly limited to the slow oxidation rate, and hence a relatively large share of air sector is used. The iron-based design has the largest size, due to its slow reduction reactivity near the exit or in the fuel purge sector where the fuel concentration is low. The gas flow temperature increases monotonically for all the cases, and is mainly determined by the solid temperature. In the periodic state, the local temperature variation is within 40 K and the thermal distortion is limited. The design of the rotary CLC is

  3. Chemical Looping Combustion of Solid Fuels in a 10 kWth Unit Combustion de charge solide en boucle chimique dans une unité de 10 kWth

    Directory of Open Access Journals (Sweden)

    Berguerand N.

    2011-02-01

    Full Text Available The present study is based on previous results from batch experiments which were conducted in a 10 kWth chemical looping combustor for solid fuels using ilmenite, an iron titanium oxide, as the oxygen carrier with two solid fuels: a Mexican petroleum coke and a South African bituminous coal. These experiments involved testing at different fuel reactor temperatures, up to 1030°C, and different particle circulation rates between the air and fuel reactors. Previous results enabled modeling of the reactor system. In particular, it was possible to derive a correlation between measured operational data and actual circulation mass flow, as well as a model that describes the carbon capture efficiency as a function of the residence time and the char reactivity. Moreover, the kinetics of char conversion could be modeled and results showed good agreement with experimental values. The purpose of the present study was to complete these results by developing a model to predict the conversion of syngas with ilmenite in the fuel reactor. Here, kinetic data from investigations of ilmenite in TGA and batch fluidized bed reactors were used. Results were compared with the actual conversions during operation in this 10 kWth unit. Cette étude est basée sur des résultats antérieurs obtenus dans une unité de combustion de charges solides en boucle chimique d’une puissance de 10 kWth. Le transporteur d’oxygène utilisé est de l’ilménite, un minerai de fer et de titane, et les charges solides étudiées sont, d’une part, un coke de pétrole mexicain et, d’autre part, un charbon bitumineux sud africain. Les résultats expérimentaux ont été obtenus à des températures allant jusqu’à 1030°C avec différents débits de transporteur d’oxygène entre les réacteurs d’oxydation et de réduction. La modélisation de la combustion en boucle chimique de charges solides a déjà permis d’établir une corrélation entre le débit de circulation de

  4. Chemical Looping with Copper Oxide as Carrier and Coal as Fuel Boucle chimique pour la combustion du charbon avec un transporteur d’oxygène à base d’oxyde de cuivre

    Directory of Open Access Journals (Sweden)

    Eyring E.M.

    2011-04-01

    Full Text Available A preliminary analysis has been conducted of the performance of a Chemical Looping system with Oxygen Uncoupling (CLOU with copper oxide as the oxygen carrier and coal approximated by carbon as the fuel. The advantages of oxygen uncoupling are demonstrated by providing the energy balances, the circulation rate of oxygen carrier, the oxygen carrier mass loadings, the carbon burnout and oxygen partial pressure in the fuel reactor. Experimental data on the cycling of cuprous oxide to cupric oxide and kinetics for the oxidation and decomposition reactions of the oxides were obtained for use in the analysis. For this preliminary study unsupported oxides were utilized. The decomposition temperatures were rapid at the high temperature of 950°C selected for the fuel reactor. The oxidation kinetics peaked at about 800°C with the decrease in rate at higher temperatures, a decrease which is attributed in the literature to the temperature dependence of the diffusional resistance of the CuO layer surrounding the Cu2O; the diffusion occurs through grain boundaries in the CuO layers and the rate of diffusion decreases as a consequence of growth of CuO grains with increasing temperature. The analysis shows the advantages of CLOU in providing rapid combustion of the carbon with carbon burnout times lower than the decomposition times of the oxygen carrier. For the full potential of CLOU to be established additional data are needed on the kinetics of supported oxides at the high temperatures (>850°C at which oxygen is released by the CuO in the fuel reactor. Une analyse préliminaire a été conduite pour estimer les performances d’un procédé en boucle chimique découplé (CLOU, chemical looping uncoupling pour la combustion du charbon avec un transporteur d’oxygène à base d’oxyde de cuivre. Les avantages de ce système sont démontrés en établissant le bilan énergétique, l’inventaire et le débit de circulation du matériau transportant l

  5. Oxygen Carriers for Chemical Looping Combustion - 4 000 h of Operational Experience Transporteurs d’oxygène pour la combustion en boucle chimique : expérience accumulée pendant 4 000 h d’opération

    Directory of Open Access Journals (Sweden)

    Lyngfelt A.

    2011-04-01

    Full Text Available Chemical Looping Combustion (CLC is a new combustion technology with inherent separation of the greenhouse gas CO2. The technology involves the use of a metal oxide as an oxygen carrier which transfers oxygen from combustion air to the fuel, and hence a direct contact between air and fuel is avoided. Two interconnected fluidized beds, a fuel reactor and an air reactor, are used in the process. The outlet gas from the fuel reactor consists of CO2 and H2O, and the latter is easily removed by condensation. Considerable research has been conducted on CLC in the last years with respect to oxygen carrier development, reactor design, system efficiencies and prototype testing. Today, more than 700 materials have been tested and the technology has been successfully demonstrated in chemical looping combustors in the size range 0.3-140 kW, using different types of oxygen carriers based on oxides of the metals Ni, Co, Fe, Cu and Mn. The total time of operational experience is more than 4 000 hours. From these tests, it can be established that almost complete conversion of the fuel can be obtained and 100% CO2 capture is possible. Most work so far has been focused on gaseous fuels, but the direct application to solid fuels is also being studied. This paper presents an overview of operational experience with oxygen carriers in chemical looping combustors. La combustion en boucle chimique (CLC est une nouvelle technique de combustion permettant la séparation intrinsèque du CO2. Dans ce procédé, un oxyde métallique est utilisé comme transporteur d’oxygène pour véhiculer l’oxygène de l’air vers le combustible, ce qui permet d’éviter un contact direct entre le combustible et l’air. Deux lits fluidisés interconnectés sont utilisés, le réacteur air et le réacteur de combustion. Les fumées du réacteur de combustion contiennent le CO2 et la vapeur d’eau qui peut être facilement éliminée par condensation. Des recherches consid

  6. Oxidation and Reduction of Iron-Titanium Oxides in Chemical Looping Combustion: A Phase-Chemical Description Oxydation et réduction des minerais de fer-titane dans la combustion en boucle chimique

    Directory of Open Access Journals (Sweden)

    den Hoed P.

    2011-05-01

    Full Text Available Ilmenite (FeTiO3 is being explored as an oxygen carrier in chemical looping processes. Its reduction and oxidation are described by the system Fe-Fe2O3-TiO2-Ti2O3. The phase diagram at 1 000°C, presented here, offers a useful tool for predicting reactions and their products. We see that Fe2TiO5 (pseudobrookite and TiO2 (rutile form a stable phase assemblage following the oxidation of FeTiO3 (ilmenite in air. The subsequent reduction of Fe2TiO5 at oxygen partial pressures of 10-15.5atm stabilizes Fe1.02Ti0.98O3, a solid solution of ilmenite. Further reduction will produce metallic iron, which compromises the integrity of the oxygen carrier for chemical looping processes. We speculate that the reduction of Fe-Ti oxides in several practical instances does not reach completion (and equilibrium under the imposed atmospheres operating in fuel reactors. L’ilménite (FeTiO3 est considéré comme un transporteur d’oxygène potentiel pour les procédés en boucle chimique. Ses mécanismes de réduction et d’oxydation sont décrits à travers le système Fe-Fe2O3-TiO2-TiO3. Le diagramme de phase à 1 000°C, présenté ici, est un outil utile pour prédire les réactions et les produits. Nous constatons que Fe2TiO5 (pseudobrookite et TiO2 (rutile forment un assemblage de phase stable après oxydation de l’ilménite (FeTiO3 dans l’air. La réduction subséquente de Fe2TiO5 à la pression partielle de 10−15,5atm stabilise vers Fe1.02Ti0.98O3, une solution solide d’ilménite. Une réduction plus poussée va produire du fer métallique et compromettre l’intégrité du transporteur d’oxygène dans la boucle chimique. Il est probable que la réduction des oxydes Fe-Ti ne soit pas, en pratique, complète et n’atteigne pas l’équilibre dans les conditions rencontrées en opération dans les réacteurs de réduction.

  7. Producción de H2 con captura de CO2 por reformado de CH4 integrado con un sistema Chemical-Looping Combustion

    OpenAIRE

    Pans Castillo, Miguel Ángel; Adánez Elorza, Juan; Gayán Sanz, Pilar

    2014-01-01

    Desde la revolución industrial, en el siglo XIX, se viene produciendo un aumento de la temperatura de la tierra y océanos, debido principalmente a las emisiones antropogénicas que han intensificado el efecto invernadero natural de la tierra, causando un calentamiento global. La mayor contribución al cambio climático lo constituyen las emisiones antropogénicas de CO2, procedentes de la combustión de combustibles fósiles. Para reducir las emisiones de CO2 se han propuesto varias alternativas, ...

  8. Effect of Ash on Oxygen Carriers for the Application of Chemical Looping Combustion to a High Carbon Char Effet des cendres sur l’activité des porteurs d’oxygène dans la combustion du charbon en boucle chimique

    Directory of Open Access Journals (Sweden)

    Rubel A.

    2011-02-01

    Full Text Available The application of Chemical Looping Combustion (CLC to solid fuels is being investigated at the University of Kentucky, Center for Applied Energy Research (CAER with the aim of the development of a Pressurized Chemical Looping Combustion/Gasification (PCLC/G process for the generation of electricity from coal. One important aspect of the CLC of solid fuel is the understanding of the effect of ash on the reactivity of Oxygen Carriers (OCs. The effect of ash on the redox capabilities of two different iron oxide OCs and on their ability to oxidize coal char was studied. To determine the effect of ash on the reactivity and recycle of the OCs through multiple redox cycles, fly ash from a coal-fired power plant was used. These experiments were performed in a TGMS system using 500 mg of ash/OC mixtures containing different ash concentrations up to 75%. The reducing gas was composed of 10% H2, 15% CO, 20% CO2, and a balance of Ar and the oxidizing gas was 20% O2 in Ar. Oxidation/reductions were carried to near completion. The ash was found to contain OC activity related to inherent iron present in the ash confirmed by XRD. This resulted in increased weight gain/loss on oxidation/reduction. The rate of oxidation/reduction increased with ash concentration due to increased porosity of the OC/ash mixture and better access of the reactive gases to the OC target sites. The two OCs were then used to combust a beneficiated coal char in the TGMS with the only oxygen supplied by an iron oxide OC. The starting mixture was 10% char and 90% of one of two OCs studied. The spent material containing reduced OC and ash was re-oxidized and 10% more char was added for a second reduction of the OC and oxidation of the added char. This procedure was repeated for 5 cycles increasing the ash concentrations from 5 to 25% in the char/ash/OC mixture. Carbon removal was 92 to 97.8 and 97.3 to 99.7% for the two different iron oxide OCs tested. Ash was not detrimental to the

  9. A Study on the Role of Reaction Modeling in Multi-phase CFD-based Simulations of Chemical Looping Combustion Impact du modèle de réaction sur les simulations CFD de la combustion en boucle chimique

    Directory of Open Access Journals (Sweden)

    Kruggel-Emden H.

    2011-03-01

    Full Text Available Chemical Looping Combustion is an energy efficient combustion technology for the inherent separation of carbon dioxide for both gaseous and solid fuels. For scale up and further development of this process multi-phase CFD-based simulations have a strong potential which rely on kinetic models for the solid/gaseous reactions. Reaction models are usually simple in structure in order to keep the computational cost low. They are commonly derived from thermogravimetric experiments. With only few CFD-based simulations performed on chemical looping combustion, there is a lack in understanding of the role and of the sensitivity of the applied chemical reaction model on the outcome of a simulation. The aim of this investigation is therefore the study of three different carrier materials CaSO4, Mn3O4 and NiO with the gaseous fuels H2 and CH4 in a batch type reaction vessel. Four reaction models namely the linear shrinking core, the spherical shrinking core, the Avrami-Erofeev and a recently proposed multi parameter model are applied and compared on a case by case basis. La combustion en boucle chimique (Chemical Looping Combustion est une technologie de combustion efficace permettant le captage in situ du CO2 pour des charges gazeuses ou solides. Dans l’optique du développement et de l’extrapolation du procédé, la CFD est un outil de simulation à fort potentiel qui s’appuie notamment sur des modèles cinétiques pour décrire les réactions gaz-solide. Ces modèles décrivant les réactions sont généralement assez simples pour limiter les temps de simulation et sont obtenus à partir d’expérimentations en thermobalance. Il y a encore peu de travaux de modélisation CFD du procédé CLC et il est difficile d’estimer l’importance du modèle décrivant les réactions chimiques sur les résultats des simulations. Le but de ce travail est donc d’étudier la combustion de charges gazeuses H2 et CH4 dans des réacteurs en batch en consid

  10. Recovery Act: Novel Oxygen Carriers for Coal-fueled Chemical Looping

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Wei-Ping; Cao, Yan

    2012-11-30

    Chemical Looping Combustion (CLC) could totally negate the necessity of pure oxygen by using oxygen carriers for purification of CO{sub 2} stream during combustion. It splits the single fuel combustion reaction into two linked reactions using oxygen carriers. The two linked reactions are the oxidation of oxygen carriers in the air reactor using air, and the reduction of oxygen carriers in the fuel reactor using fuels (i.e. coal). Generally metal/metal oxides are used as oxygen carriers and operated in a cyclic mode. Chemical looping combustion significantly improves the energy conversion efficiency, in terms of the electricity generation, because it improves the reversibility of the fuel combustion process through two linked parallel processes, compared to the conventional combustion process, which is operated far away from its thermo-equilibrium. Under the current carbon-constraint environment, it has been a promising carbon capture technology in terms of fuel combustion for power generation. Its disadvantage is that it is less mature in terms of technological commercialization. In this DOE-funded project, accomplishment is made by developing a series of advanced copper-based oxygen carriers, with properties of the higher oxygen-transfer capability, a favorable thermodynamics to generate high purity of CO{sub 2}, the higher reactivity, the attrition-resistance, the thermal stability in red-ox cycles and the achievement of the auto-thermal heat balance. This will be achieved into three phases in three consecutive years. The selected oxygen carriers with final-determined formula were tested in a scaled-up 10kW coal-fueled chemical looping combustion facility. This scaled-up evaluation tests (2-day, 8-hour per day) indicated that, there was no tendency of agglomeration of copper-based oxygen carriers. Only trace-amount of coke or carbon deposits on the copper-based oxygen carriers in the fuel reactor. There was also no evidence to show the sulphidization of oxygen

  11. Chemical looping integration with a carbon dioxide gas purification unit

    Science.gov (United States)

    Andrus, Jr., Herbert E.; Jukkola, Glen D.; Thibeault, Paul R.; Liljedahl, Gregory N.

    2017-01-24

    A chemical looping system that contains an oxidizer and a reducer is in fluid communication with a gas purification unit. The gas purification unit has at least one compressor, at least one dryer; and at least one distillation purification system; where the gas purification unit is operative to separate carbon dioxide from other contaminants present in the flue gas stream; and where the gas purification unit is operative to recycle the contaminants to the chemical looping system in the form of a vent gas that provides lift for reactants in the reducer.

  12. Chemical Looping Reforming for H2, CO and Syngas Production

    Energy Technology Data Exchange (ETDEWEB)

    Bhavsar,Saurabh; Najera,Michelle; Solunke,Rahul; Veser,Götz

    2001-06-06

    We demonstrate that the extension of CLC onto oxidants beyond air opens new, highly efficient pathways for production of ultra-pure hydrogen, activation of CO{sub 2} via reduction to CO, and are currently working on production of syngas using nanocomposite Fe-BHA. CLR hold great potential due to fuel flexibility and CO{sub 2} capture. Chemical Looping Combustion (CLC) is a novel clean combustion technology which offers an elegant and highly efficient route for fossil fuel combustion. In CLC, combustion of a fuel is broken down into two spatially separated steps. In the reducer, the oxygen carrier (typically a metal) supplies the stoichiometric oxygen required for fuel combustion. In the oxidizer, the oxygen-depleted carrier is then re-oxidized with air. After condensation of steam from the effluent of the reducer, a high-pressure, high-purity sequestration-ready CO{sub 2} stream is obtained. In the present study, we apply the CLC principle to the production of high-purity H{sub 2}, CO, and syngas streams by replacing air with steam and/or CO{sub 2} as oxidant, respectively. Using H{sub 2}O as oxidant, pure hydrogen streams can be obtained. Similarly, using CO{sub 2} as oxidant, CO is obtained, thus opening an efficient route for CO{sub 2} utilization. Using steam and CO{sub 2} mixtures for carrier oxidation should thus allow production of syngas with adjustable CO:H{sub 2} ratios. Overall, these processes result in Chemical Looping Reforming (CLR), i.e. the net overall reaction is the steam and/or dry reforming of the respective fuel.

  13. Chemical Looping Autothermal Reforming at a 120 kW Pilot Rig

    Science.gov (United States)

    Bofhàr-Nordenkampf, Johannes; Pröll, Tobias; Kolbitsch, Philipp; Hofbauer, Hermann

    Chemical looping with selective oxygen transport allows two step combustion or autothermal reforming without mixing of fuel and air. The reactor system consists of two reactors, an air reactor and a fuel reactor with a suitable oxygen carrier that transports the necessary oxygen for operation. In the present study, a highly active nickel based oxygen carrier is tested in a novel dual circulating fluidized bed (DCFB) system at a scale of 120 kW fuel power. The mean particle size of the oxygen carrier is 120 μm and the pilot rig is fueled with natural gas. For the investigated oxygen carrier high CH4 conversion is achieved. Air/fuel ratio is varied at three different fuel reactor temperatures. For chemical looping reforming one can observe synthesis gas composition close to thermodynamic equilibrium. In spite of the fact that no additional steam has been added to the fuel besides the one present through steam fluidization of the loop seals, coke formation does not occur at global stoichiometric air/fuel ratios above 0.46.

  14. The Role of Attrition and Solids Recovery in a Chemical Looping Combustion Process Effet de l’attrition et de la récupération des particules dans le procédé de combustion en boucle chimique

    Directory of Open Access Journals (Sweden)

    Kramp M.

    2011-05-01

    Full Text Available In the present work, the steady-state behavior of a Chemical Looping Combustion process of interconnected fluidized bed reactors is simulated. The simulations have been carried out in two different scales, 50 kWth and 100 MWth. Attrition model derived from small scale laboratory experiments has been employed for the prediction of the process behavior in terms of attrition and Oxygen Carrier loss. Information on Oxygen Carrier characteristics and reaction kinetics were taken from literature. Realistic circulation mass flows of Oxygen Carrier particles are obtained and Oxygen Carrier losses are quantified. The large scale process looses significantly more Oxygen Carrier than the small scale process based on the same amount of thermal energy produced. Incomplete conversion in the air reactor could be identified as a critical point. Another issue is the fuel gas bypassing the Oxygen Carrier particles through bubbles in the large scale process which leads to lowered fuel conversions. The simulations indicate that a similar performance of a pilot scale and a large scale process is not guaranteed due to the scale-up effect on fluid dynamics. Furthermore, the simulations allow an assessment of the influence of the quality of the solids recovery system on the Oxygen Carrier loss. The distribution of the losses between possible origins is investigated and different changes in the solids recovery system are discussed regarding their potential to decrease the Oxygen Carrier loss. For example, the addition of a second-stage cyclone after the air reactor of the large scale process reduces the Oxygen Carrier loss significantly. Le présent travail propose un modèle de simulation en continu du procédé de combustion en boucle chimique constitué de deux lits fluidisés interconnectés. Les simulations ont été conduites à deux échelles 50 kWth correspondant à une installation pilote et 100 MWth correspondant à une installation industrielle. Un modèle d

  15. Process/Equipment Co-Simulation on Syngas Chemical Looping Process

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Liang; Zhou, Qiang; Fan, Liang-Shih

    2012-09-30

    The chemical looping strategy for fossil energy applications promises to achieve an efficient energy conversion system for electricity, liquid fuels, hydrogen and/or chemicals generation, while economically separate CO{sub 2} by looping reaction design in the process. Chemical looping particle performance, looping reactor engineering, and process design and applications are the key drivers to the success of chemical looping process development. In order to better understand and further scale up the chemical looping process, issues such as cost, time, measurement, safety, and other uncertainties need to be examined. To address these uncertainties, advanced reaction/reactor modeling and process simulation are highly desired and the modeling efforts can accelerate the chemical looping technology development, reduce the pilot-scale facility design time and operating campaigns, as well as reduce the cost and technical risks. The purpose of this work is thus to conduct multiscale modeling and simulations on the key aspects of chemical looping technology, including particle reaction kinetics, reactor design and operation, and process synthesis and optimization.

  16. Using Low-Cost Iron-Based Materials as Oxygen Carriers for Chemical Looping Combustion Utilisation de matériaux bon marché à base de fer comme transporteur d’oxygène dans la combustion en boucle chimique

    Directory of Open Access Journals (Sweden)

    Jerndal E.

    2011-03-01

    Full Text Available In chemical looping combustion with solid fuels, the oxygen-carrier lifetime is expected to be shorter than with gaseous fuels. Therefore, it is particularly important to use low-cost oxygen carriers in solid fuel applications. Apart from being cheap, these oxygen carriers should be able to convert the CO and H2 produced from the solid fuel gasification and be sufficiently hard to withstand fragmentation. Several low-cost iron-based materials displayed high conversion of syngas and high mechanical strength and can be used for further development of the technology. These materials include oxide scales from Sandvik and Scana and an iron ore from LKAB. All tested oxygen carriers showed higher gas conversion than a reference sample, the mineral ilmenite. Generally, softer oxygen carriers were more porous and appeared to have a higher reactivity towards syngas. When compared with ilmenite, the conversion of CO was higher for all oxygen carriers and the conversion of H2 was higher when tested for longer reduction times. The oxygen carrier Sandvik 2 displayed the highest conversion of syngas and was therefore selected for solid fuel experiments. The conversion rate of solid fuels was higher with Sandvik 2 than with the reference sample, ilmenite. Pour appliquer la combustion en boucle chimique à des charges solides, il est important d’utiliser des matériaux transporteurs d’oxygène bon marché. En effet, la durée de vie du transporteur d’oxygène risque d’être plus courte sur charge solide que sur charge gazeuse. Ces matériaux doivent également bien convertir le monoxyde de carbone et l’hydrogène résultant de la gasification, tout en étant suffisamment durs pour résister à la fragmentation. Plusieurs matériaux ont montré un potentiel de conversion élevé sur le gaz de synthèse ainsi qu’une résistance mécanique élevée, ce qui permet d’envisager leur utilisation lors des développements futurs de la technologie. Parmi ces

  17. Nonlinear model predictive control for chemical looping process

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Abhinaya; Lei, Hao; Lou, Xinsheng

    2017-08-22

    A control system for optimizing a chemical looping ("CL") plant includes a reduced order mathematical model ("ROM") that is designed by eliminating mathematical terms that have minimal effect on the outcome. A non-linear optimizer provides various inputs to the ROM and monitors the outputs to determine the optimum inputs that are then provided to the CL plant. An estimator estimates the values of various internal state variables of the CL plant. The system has one structure adapted to control a CL plant that only provides pressure measurements in the CL loops A and B, a second structure adapted to a CL plant that provides pressure measurements and solid levels in both loops A, and B, and a third structure adapted to control a CL plant that provides full information on internal state variables. A final structure provides a neural network NMPC controller to control operation of loops A and B.

  18. Chemical looping reforming of generator gas

    Energy Technology Data Exchange (ETDEWEB)

    Mendiara, T.; Jensen, Anker; Glarborg, P.

    2010-02-15

    The main objective of this work is to investigate the carbon deposition during reforming of hydrocarbons in a Chemical Looping Reformer (CLR). This knowledge is needed to asses the viability of the CLR technology in reforming tar from biomass gasification preserving lighter hydrocarbons and minimizing the carbon formation during the process. Two different setups were used to test the reactivity of the different samples in the conditions of interest for the tar reforming process: 1) Fixed bed flow reactor (FR), and 2) Thermogravimetric analyzer (TGA). In the experiments, the gas atmosphere was switched from reducing to oxidizing atmosphere in every cycle. During the oxidizing cycle, the carrier was regenerated using a mixture of oxygen and nitrogen. Four different oxygen carriers based on nickel (Ni40 and Ni60), manganese (Mn) and ilmenite (Fe) were tested. In the tests, toluene was used to simulate the tars. The Fe and the Mn carrier reacted to a small extent with methane at the highest temperature studied, 800 degrees C. The Ni-carriers did not react at 600 degrees C at first, but they showed some reactivity after having been activated at the higher temperature. Carbon formation occurred with the Ni-carriers, more so with the Ni60 than the Ni40. Ni40, Mn and Fe were activated at the higher temperature. However, Fe showed only low capacity. Ni60 showed no capability of tar reforming. Ni40 showed a high tendency to carbon formation at 800 degrees C, but the formation could be lowered by changing some parameters. Mn formed almost no carbon. Ni40 and Mn were chosen for further studies. Carbon deposition occurred for both Ni40 and Mn, but the amount deposited for Ni40 was about 10 times bigger. Ni40 reacted with the methane and toluene only at 800 degrees C. The conversion over Mn was not as big as for toluene alone. Carbon was formed from carbon monoxide on the Ni40 carrier and on the Mn, but to a much less extent on the latter one. The presence of hydrogen decreased

  19. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, NOX CONTROL TECHNOLOGIES, CATALYTICA COMBUSTION SYSTEMS, INC., XONON FLAMELESS COMBUSTION SYSTEM

    Science.gov (United States)

    The Environmental Technology Verification report discusses the technology and performance of the Xonon Cool Combustion System manufactured by Catalytica Energy Systems, Inc., formerly Catalytica Combustion Systems, Inc., to control NOx emissions from gas turbines that operate wit...

  20. Jet plume injection and combustion system for internal combustion engines

    Science.gov (United States)

    Oppenheim, Antoni K.; Maxson, James A.; Hensinger, David M.

    1993-01-01

    An improved combustion system for an internal combustion engine is disclosed wherein a rich air/fuel mixture is furnished at high pressure to one or more jet plume generator cavities adjacent to a cylinder and then injected through one or more orifices from the cavities into the head space of the cylinder to form one or more turbulent jet plumes in the head space of the cylinder prior to ignition of the rich air/fuel mixture in the cavity of the jet plume generator. The portion of the rich air/fuel mixture remaining in the cavity of the generator is then ignited to provide a secondary jet, comprising incomplete combustion products which are injected into the cylinder to initiate combustion in the already formed turbulent jet plume. Formation of the turbulent jet plume in the head space of the cylinder prior to ignition has been found to yield a higher maximum combustion pressure in the cylinder, as well as shortening the time period to attain such a maximum pressure.

  1. Experimental investigation of the chemical looping method on a 1 MW pilot plant; Experimentelle Untersuchung des Chemical Looping Verfahrens an einer 1 MW Versuchsanlage

    Energy Technology Data Exchange (ETDEWEB)

    Orth, Matthias

    2014-08-27

    Attempting to counteract the consequences of climate change, leading industrial nations have agreed on reducing their CO{sub 2} emissions significantly. To reach these reduction goals, it is essential to reduce the CO{sub 2} emissions in the field of energy conversion. This PHD thesis covers the field of chemical looping combustion, a technology that uses fossil fuels for energy conversion with inherent capture of CO{sub 2}. Since the research regarding chemical looping had so far focused mainly on lab scale or small scale experiments, a 1 MW pilot plant has been erected at Technische Universitaet Darmstadt in order to investigate the process in a semi-industrial scale and to check the process efficiency with commercially usable equipment. This pilot consists of two interconnected fluidized bed reactors and has an overall height of more than 11 m. In this thesis, some experiments with ilmenite - used as the oxygen carrier - are explained. Furthermore, the design, erection and commissioning of the pilot plant are presented as well as the results of the first test campaigns. The evaluation of the latter proves that the process can be handled in the design configuration and that CO{sub 2} can be safely captured in a pilot plant of this scale.

  2. An investigation of synthetic fuel production via chemical looping.

    Science.gov (United States)

    Zeman, Frank; Castaldi, Marco

    2008-04-15

    Producing liquid hydrocarbon fuels with a reduced greenhouse gas emissions profile would ease the transition to a carbon-neutral energy sector with the transportation industry being the immediate beneficiary followed by the power industry. Revolutionary solutions in transportation, such as electricity and hydrogen, depend on the deployment of carbon capture and storage technologies and/or renewable energy systems. Additionally, high oil prices may increase the development of unconventional sources, such as tar sands, that have a higher emissions profile. One process that is gaining interest is a system for producing reduced carbon fuels though chemical looping technologies. An investigation of the implications of such a process using methane and carbon dioxide that is reformed to yield methanol has been done. An important aspect of the investigation is the use of off-the-shelf technologies to achieve the results. The ability of the process to yield reduced emissions fuels depends on the source for the feed and process heat. For the range of conditions considered, the emissions profile of methanol produced in this method varies from 0.475 to 1.645 moles carbon dioxide per mole methanol. The upper bound can be lowered to 0.750 by applying CCS and/ or using nonfossil heat sources for the reforming. The process provides an initial pathway to incorporate CO2 into fuels independent of electrolytic hydrogen or developments in other sectors of the economy.

  3. Chemical looping for syngas & hydrogen production with parallel CO2 activation

    Science.gov (United States)

    More, Amey Sudhir

    The anticipated rise in global population and the rapidly growing economies of the developing world will dramatically increase the demand for consumer products, which are derived mostly from commodity chemicals. While the abundant natural gas (>95% CH4) reserves can potentially enable bulk chemical production, all commercial routes for methane (CH4) upgrading require its conversion to syngas (mixture of CO+H2) as a first step. Not only are current syngas production technologies highly energy and capital intensive, but they also result in large CO2 emissions. Overall, rising environmental concerns, increase demand for bulk chemicals and availability of abundant natural gas reserves together motivate the need to develop alternative processes for syngas production with CO2 utilization. 'Chemical Looping Combustion' is a clean combustion technology, which enables fossil fuel combustion with inherent CO2 capture based on the cyclic oxidation and reduction of an oxygen carrier. While most efforts in chemical looping (CL) are focused on combustion, we demonstrate the application of the "CL principle"--the periodic oxidation and reduction of a metal oxide to couple two independent redox reactions--to the activation of CO2 via reduction to CO (a chemical feedstock) and upgrading of CH4 to syngas or hydrogen. In this work, we investigate and compare CO2 activation via CL in two different operating modes: In the first scheme, CO2 reduction is coupled with CH4 oxidation by using mixtures of Fe and Ni (as alloys or simple physical mixtures) to produce CO and syngas product streams. In the second operating scheme, monometallic Ni carriers are utilized to catalytically crack CH4, producing pure H2 streams. The solid carbon deposits are then burnt off with CO2, overall producing separate CO and H2 product streams. Our investigations demonstrate the potential of CO2 as a "soft" oxidant which enables selective oxidation reactions in all the configurations, and thereby establish the

  4. Secondary combustion system for woodburning stove

    Energy Technology Data Exchange (ETDEWEB)

    von Conta, P. E. W.

    1985-11-19

    A secondary combustion system for a woodburning stove employs a concave shaped screen for dispersing exhaust gases. A mixing chamber is formed in an insulated conduit between the concave screen and a second planar screen. The planar screen is perforated to form a random array of flaps which increase the turbulence of the exhaust stream so that a secondary combustion of the exhaust gases is produced.

  5. Operation of the NETL Chemical Looping Reactor with Natural Gas and a Novel Copper-Iron Material

    Energy Technology Data Exchange (ETDEWEB)

    Bayham, Sanuel [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Straub, Doug [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Weber, Justin [National Energy Technology Lab. (NETL), Morgantown, WV (United States)

    2017-02-01

    As part of the U.S. Department of Energy’s Advanced Combustion Program, the National Energy Technology Laboratory’s Research and Innovation Center (NETL R&IC) is investigating the feasibility of a novel combustion concept in which the GHG emissions can be significantly reduced. This concept involves burning fuel and air without mixing these two reactants. If this concept is technically feasible, then CO2 emissions can be significantly reduced at a much lower cost than more conventional approaches. This indirect combustion concept has been called Chemical Looping Combustion (CLC) because an intermediate material (i.e., a metaloxide) is continuously cycled to oxidize the fuel. This CLC concept is the focus of this research and will be described in more detail in the following sections.

  6. Combustion modeling in advanced gas turbine systems

    Energy Technology Data Exchange (ETDEWEB)

    Smoot, L.D.; Hedman, P.O.; Fletcher, T.H. [Brigham Young Univ., Provo, UT (United States)] [and others

    1995-10-01

    The goal of the U.S. Department of Energy`s Advanced Turbine Systems (ATS) program is to help develop and commercialize ultra-high efficiency, environmentally superior, and cost competitive gas turbine systems for base-load applications in the utility, independent power producer, and industrial markets. Combustion modeling, including emission characteristics, has been identified as a needed, high-priority technology by key professionals in the gas turbine industry.

  7. A comparative study of geopolymers synthesized from OXY-combustion and chemical looping combustion bottom ashes

    CSIR Research Space (South Africa)

    Nkuna, CN

    2017-04-01

    Full Text Available silicate (Na2SiO2) and sodium hydroxide solutions (5M, 10M and 15M) and the pastes were cured at 60°C for 10days. The properties of the geopolymers were characterized using: TGA, FTIR and SEM-EDX techniques. TGA analysis showed that FBC geopolymer with 5M...

  8. 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.

  9. Comparison of Iron and Tungsten Based Oxygen Carriers for Hydrogen Production Using Chemical Looping Reforming

    Science.gov (United States)

    Khan, M. N.; Shamim, T.

    2017-08-01

    Hydrogen production by using a three reactor chemical looping reforming (TRCLR) technology is an innovative and attractive process. Fossil fuels such as methane are the feedstocks used. This process is similar to a conventional steam-methane reforming but occurs in three steps utilizing an oxygen carrier. As the oxygen carrier plays an important role, its selection should be done carefully. In this study, two oxygen carrier materials of base metal iron (Fe) and tungsten (W) are analysed using a thermodynamic model of a three reactor chemical looping reforming plant in Aspen plus. The results indicate that iron oxide has moderate oxygen carrying capacity and is cheaper since it is abundantly available. In terms of hydrogen production efficiency, tungsten oxide gives 4% better efficiency than iron oxide. While in terms of electrical power efficiency, iron oxide gives 4.6% better results than tungsten oxide. Overall, a TRCLR system with iron oxide is 2.6% more efficient and is cost effective than the TRCLR system with tungsten oxide.

  10. 14 CFR 25.833 - Combustion heating systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Combustion heating systems. 25.833 Section... AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Ventilation and Heating § 25.833 Combustion heating systems. Combustion heaters must be approved. Pressurization ...

  11. Combustion powered thermophotovoltaic emitter system

    Energy Technology Data Exchange (ETDEWEB)

    McHenry, R.S. [Naval Academy, Annapolis, MD (United States). Naval Architecture, Ocean and Marine Engineering

    1995-07-01

    The US Naval Academy (USNA) has recently completed an engineering design project for a high temperature thermophotovoltaic (TPV) photon emitter. The final apparatus was to be portable, completely self contained, and was to incorporate cycle efficiency optimization such as exhaust stream recuperation. Through computer modeling and prototype experimentation, a methane fueled emitter system was designed from structural ceramic materials to fulfill the high temperature requirements necessary for high system efficiency. This paper outlines the engineering design process, discusses obstacles and solutions encountered, and presents the final design.

  12. Assessment of Literature Related to Combustion Appliance Venting Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, V. H.; Less, B. D.; Singer, B. C.; Stratton, J. C.; Wray, C. P.

    2015-02-01

    In many residential building retrofit programs, air tightening to increase energy efficiency is often constrained by safety concerns with naturally vented combustion appliances. Tighter residential buildings more readily depressurize when exhaust equipment is operated, making combustion appliances more prone to backdraft or spill combustion exhaust into the living space. Several measures, such as installation guidelines, vent sizing codes, and combustion safety diagnostics, are in place with the intent to prevent backdrafting and combustion spillage, but the diagnostics conflict and the risk mitigation objective is inconsistent. This literature review summarizes the metrics and diagnostics used to assess combustion safety, documents their technical basis, and investigates their risk mitigations. It compiles information from the following: codes for combustion appliance venting and installation; standards and guidelines for combustion safety diagnostics; research evaluating combustion safety diagnostics; research investigating wind effects on building depressurization and venting; and software for simulating vent system performance.

  13. Establishment of an Environmental Control Technology Laboratory with a Circulating Fluidized-Bed Combustion System

    Energy Technology Data Exchange (ETDEWEB)

    Wei-Ping Pan; Yan Cao; John Smith

    2008-05-31

    particulate filtration technologies. Major tasks during this period of the funded project's timeframe included: (1) Conducting pretests on a laboratory-scale simulated FBC system; (2) Completing detailed design of the bench-scale CFBC system; (3) Contracting potential bidders to fabricate of the component parts of CFBC system; (4) Assembling CFBC parts and integrating system; (5) Resolving problems identified during pretests; (6) Testing with available Powder River Basin (PRB) coal and co-firing of PRB coal with first wood pallet and then chicken wastes; and (7) Tuning of CFBC load. Following construction system and start-up of this 0.6 MW CFBC system, a variety of combustion tests using a wide range of fuels (high-sulfur coals, low-rank coals, MSW, agricultural waste, and RDF) under varying conditions were performed to analyze and monitor air pollutant emissions. Data for atmospheric pollutants and the methodologies required to reduce pollutant emissions were provided. Integration with a selective catalytic reduction (SCR) slipstream unit did mimic the effect of flue gas composition, including trace metals, on the performance of the SCR catalyst to be investigated. In addition, the following activities were also conducted: (1) Developed advanced mercury oxidant and adsorption additives; (2) Performed laboratory-scale tests on oxygen-fuel combustion and chemical looping combustion; and (3) Conducted statistical analysis of mercury emissions in a full-scale CFBC system.

  14. Future fundamental combustion research for aeropropulsion systems

    Science.gov (United States)

    Mularz, E. J.

    1985-01-01

    Physical fluid mechanics, heat transfer, and chemical kinetic processes which occur in the combustion chamber of aeropropulsion systems were investigated. With the component requirements becoming more severe for future engines, the current design methodology needs the new tools to obtain the optimum configuration in a reasonable design and development cycle. Research efforts in the last few years were encouraging but to achieve these benefits research is required into the fundamental aerothermodynamic processes of combustion. It is recommended that research continues in the areas of flame stabilization, combustor aerodynamics, heat transfer, multiphase flow and atomization, turbulent reacting flows, and chemical kinetics. Associated with each of these engineering sciences is the need for research into computational methods to accurately describe and predict these complex physical processes. Research needs in each of these areas are highlighted.

  15. Secondary combustion system for wood burning stove

    Energy Technology Data Exchange (ETDEWEB)

    von Conta, P.E.W.

    1986-12-16

    This patent describes an improved secondary combustion system for combusting the exhaust gases exiting from a fire box in a wood burning stove comprising: an insulated conduit defining an exhaust passageway leading from an intake opening to an exit opening; screen means interposed across the exhaust passageway in the vicinity of the intake opening to impart a rapid acceleration to a gas stream entering the exhaust passageway; rotation means to impart a rotation to the gas stream in a first portion of the exhaust passageway; counter-rotation means to impart a counter-rotation to the gas stream in a second portion of the exhaust passageway; deceleration means to decelerate the gas stream in the second portion of the exhaust passageway; and secondary air means to inject a source of secondary air into the exhaust passageway.

  16. Wood combustion systems: status of environmental concerns

    Energy Technology Data Exchange (ETDEWEB)

    Dunwoody, J.E.; Takach, H.; Kelley, C.S.; Opalanko, R.; High, C.; Fege, A.

    1980-01-01

    This document addresses the uncertainties about environmental aspects of Wood Combustion Systems that remain to be resolved through research and development. The resolution of these uncertainties may require adjustments in the technology program before it can be commercialized. The impacts and concerns presented in the document are treated generically without reference to specific predetermined sites unless these are known. Hence, site-specific implications are not generally included in the assessment. The report consists of two main sections which describe the energy resource base involved, characteristics of the technology, and introduce the environmental concerns of implementing the technology; and which review the concerns related to wood combustion systems which are of significance for the environment. It also examines the likelihood and consequence of findings which might impede wood commercialization such as problems and uncertainties stemming from current or anticipated environmental regulation, or costs of potential environmental controls. This document is not a formal NEPA document. Appropriate NEPA documentation will be prepared after a formal wood combustion commercialization program is approved by DOE.

  17. 76 FR 16646 - Circadian, Inc., Clean Energy Combustion, Inc. (n/k/a Clean Energy Combustion Systems, Inc...

    Science.gov (United States)

    2011-03-24

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION Circadian, Inc., Clean Energy Combustion, Inc. (n/k/a Clean Energy Combustion Systems, Inc... concerning the securities of Clean Energy Combustion, Inc. (n/k/a Clean Energy Combustion Systems, Inc...

  18. 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

  19. High efficiency stoichiometric internal combustion engine system

    Science.gov (United States)

    Winsor, Richard Edward; Chase, Scott Allen

    2009-06-02

    A power system including a stoichiometric compression ignition engine in which a roots blower is positioned in the air intake for the engine to control air flow. Air flow is decreased during part power conditions to maintain the air-fuel ratio in the combustion chamber of the engine at stoichiometric, thus enabling the use of inexpensive three-way catalyst to reduce oxides of nitrogen. The roots blower is connected to a motor generator so that when air flow is reduced, electrical energy is stored which is made available either to the roots blower to temporarily increase air flow or to the system electrical load and thus recapture energy that would otherwise be lost in reducing air flow.

  20. DEMONSTRATION BULLETIN: CELLO PULSE COMBUSTION BURNER SYSTEM/SONOTECH INC.

    Science.gov (United States)

    Sonotech, Inc. (Sonotech), of Atlanta, GA, the developer of the Cello® pulse combustion burner, claims that its burner system can be beneficial to a variety of combustion processes. The system incorporates a combustor that can be tuned to induce large amplitude sonic pulsation...

  1. Durable Feedback Control System for Small Scale Wood Chip Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Korpela, T.; Bjoerkqvist, T.; Lautala, P. (Tampere Univ. of Technology, Dept. of Automation Science and Engineering, FIN-33101 Tampere (Finland)). E-mail: timo.korpela@tut.fi

    2008-10-15

    The purpose is to control wood chip combustion in an inexpensive and durable way. A control concept in order to reduce the effect of fluctuation of the fuel feed is introduced. The concept is based on temperature and lambda measurements. The main task of the control system is to set the fuel feed at a desired level after a change in the combustion conditions. Additionally, temporary fluctuations of the degree of filling of feeding screw are compensated. Test results of a 80 kW and a 200 kW commercial wood chip fired systems are introduced. The process experiments indicate that the high level control system is able to adapt to varying combustion conditions and to maintain low emission levels. Furthermore, passive means that can be exploited to stabilize the combustion are discussed. As the control concept is not dependent on the design of the combustion system, the concept is adaptable to present systems

  2. Internet of Things Based Combustible Ice Safety Monitoring System Framework

    Science.gov (United States)

    Sun, Enji

    2017-05-01

    As the development of human society, more energy is requires to meet the need of human daily lives. New energies play a significant role in solving the problems of serious environmental pollution and resources exhaustion in the present world. Combustible ice is essentially frozen natural gas, which can literally be lit on fire bringing a whole new meaning to fire and ice with less pollutant. This paper analysed the advantages and risks on the uses of combustible ice. By compare to other kinds of alternative energies, the advantages of the uses of combustible ice were concluded. The combustible ice basic physical characters and safety risks were analysed. The developments troubles and key utilizations of combustible ice were predicted in the end. A real-time safety monitoring system framework based on the internet of things (IOT) was built to be applied in the future mining, which provide a brand new way to monitoring the combustible ice mining safety.

  3. Simulation of the Fuel Reactor of a Coal-Fired Chemical Looping Combustor

    Science.gov (United States)

    Mahalatkar, Kartikeya; O'Brien, Thomas; Huckaby, E. David; Kuhlman, John

    2009-06-01

    Responsible carbon management (CM) will be required for the future utilization of coal for power generation. CO2 separation is the more costly component of CM, not sequestration. Most methods of capture require a costly process of gas separation to obtain a CO2-rich gas stream. However, recently a process termed Chemical Looping Combustion (CLC) has been proposed, in which an oxygen-carrier is used to provide the oxygen for combustion. This process quite naturally generates a separate exhaust gas stream containing mainly H2O and CO2 but requires two reaction vessels, an Air Reactor (AR) and a Fuel Reactor (FR). The carrier (M for metal, the usual carrier) is oxidized in the AR. This highly exothermic process provides heat for power generation. The oxidized carrier (MO) is separated from this hot, vitiated air stream and transported to the FR where it oxidizes the hydrocarbon fuel, yielding an exhaust gas stream of mainly H2O and CO2. This process is usually slightly endothermic so that the carrier must also transport the necessary heat of reaction. The reduced carrier (M) is then returned to the air reactor for regeneration, hence the term "looping." The net chemical reaction and energy release is identical to that of conventional combustion of the fuel. However, CO2 separation is easily achieved, the only operational penalty being the slight pressure losses required to circulate the carrier. CLC requires many unit operations involving gas-solid or granular flow. To utilize coal in the fuel reactor, in either a moving bed or bubbling fluidized bed, the granular flow is especially critical. The solid coal fuel must be heated by the recycled metal oxide, driving off moisture and volatile material. The remaining char must be gasified by H2O (or CO2), which is recycled from the product stream. The gaseous product of these reactions must then contact the MO before leaving the bed to obtain complete conversion to H2O and CO2. Further, the reduced M particles must be

  4. Hybrid lean premixing catalytic combustion system for gas turbines

    Science.gov (United States)

    Critchley, Ian L.

    2003-12-09

    A system and method of combusting a hydrocarbon fuel is disclosed. The system combines the accuracy and controllability of an air staging system with the ultra-low emissions achieved by catalytic combustion systems without the need for a pre-heater. The result is a system and method that is mechanically simple and offers ultra-low emissions over a wide range of power levels, fuel properties and ambient operating conditions.

  5. Operation of the NETL Chemical Looping Reactor with Natural Gas and a Novel Copper-Iron Material

    Energy Technology Data Exchange (ETDEWEB)

    Straub, Douglas [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Bayham, Samuel [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Weber, Justin [National Energy Technology Lab. (NETL), Morgantown, WV (United States)

    2017-02-21

    The proposed Clean Power Plan requires CO2 emission reductions of 30% by 2030 and further reductions are targeted by 2050. The current strategies to achieve the 30% reduction targets do not include options for coal. However, the 2016 Annual Energy Outlook suggests that coal will continue to provide more electricity than renewable sources for many regions of the country in 2035. Therefore, cost effective options to reduce greenhouse gas emissions from fossil fuel power plants are vital in order to achieve greenhouse gas reduction targets beyond 2030. As part of the U.S. Department of Energy’s Advanced Combustion Program, the National Energy Technology Laboratory’s Research and Innovation Center (NETL R&IC) is investigating the feasibility of a novel combustion concept in which the GHG emissions can be significantly reduced. This concept involves burning fuel and air without mixing these two reactants. If this concept is technically feasible, then CO2 emissions can be significantly reduced at a much lower cost than more conventional approaches. This indirect combustion concept has been called Chemical Looping Combustion (CLC) because an intermediate material (i.e., a metal-oxide) is continuously cycled to oxidize the fuel. This CLC concept is the focus of this research and will be described in more detail in the following sections. The solid material that is used to transport oxygen is called an oxygen carrier material. The cost, durability, and performance of this material is a key issue for the CLC technology. Researchers at the NETL R&IC have developed an oxygen carrier material that consists of copper, iron, and alumina. This material has been tested extensively using lab scale instruments such as thermogravimetric analysis (TGA), scanning electron microscopy (SEM), mechanical attrition (ASTM D5757), and small fluidized bed reactor tests. This report will describe the results from a realistic, circulating, proof-of-concept test that was

  6. NATO Workshop on Soot in Combustion Systems

    CERN Document Server

    Prado, G

    1983-01-01

    Our interest in Mulhouse for carbon black and soot began some 30 years ago when J.B. Donnet developed the concept of surface chemistry of carbon and its involvement in interactions with gas, liquid and solid phases. In the late sixties, we began to study soot formation in pyrolytic systems and later on in flames. The idea of organ1z1ng a meeting on soot formation originated some four or five years ago, through discussions among Professor J.B. Howard, Dr. A. D'Alessio and ourselves. At that time the scientific community was becoming aware of the necessity to strictly control soot formation and emission. Being involved in the study of surface properties of carbon black as well as of formation of soot, we realized that the combustion community was not always fully aware of the progress made by the physical-chemists on carbon black. Reciprocally, the carbon specialists were often ignoring the research carried out on soot in flames. One objective of this workshop was to stimulate discussions between these two scie...

  7. Assessment of Literature Related to Combustion Appliance Venting Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, Vi H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Singer, Brett C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Stratton, Chris [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wray, Craig P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-06-01

    In many residential building retrofit programs, air tightening to increase energy efficiency is constrained by concerns about related impacts on the safety of naturally vented combustion appliances. Tighter housing units more readily depressurize when exhaust equipment is operated, making combustion appliances more prone to backdraft or spillage. Several test methods purportedly assess the potential for depressurization-induced backdrafting and spillage, but these tests are not robustly reliable and repeatable predictors of venting performance, in part because they do not fully capture weather effects on venting performance. The purpose of this literature review is to investigate combustion safety diagnostics in existing codes, standards, and guidelines related to combustion appliances. This review summarizes existing combustion safety test methods, evaluations of these test methods, and also discusses research related to wind effects and the simulation of vent system performance. Current codes and standards related to combustion appliance installation provide little information on assessing backdrafting or spillage potential. A substantial amount of research has been conducted to assess combustion appliance backdrafting and spillage test methods, but primarily focuses on comparing short-term (stress) induced tests and monitoring results. Monitoring, typically performed over one week, indicated that combinations of environmental and house operation characteristics most conducive to combustion spillage were rare. Research, to an extent, has assessed existing combustion safety diagnostics for house depressurization, but the objectives of the diagnostics, both stress and monitoring, are not clearly defined. More research is also needed to quantify the frequency of test “failure” occurrence throughout the building stock and assess the statistical effects of weather (especially wind) on house depressurization and in turn on combustion appliance venting

  8. Regenerable MgO promoted metal oxide oxygen carriers for chemical looping combustion

    Science.gov (United States)

    Siriwardane, Ranjani V.; Miller, Duane D.

    2014-08-19

    The disclosure provides an oxygen carrier comprised of a plurality of metal oxide particles in contact with a plurality of MgO promoter particles. The MgO promoter particles increase the reaction rate and oxygen utilization of the metal oxide when contacting with a gaseous hydrocarbon at a temperature greater than about 725.degree. C. The promoted oxide solid is generally comprised of less than about 25 wt. % MgO, and may be prepared by physical mixing, incipient wetness impregnation, or other methods known in the art. The oxygen carrier exhibits a crystalline structure of the metal oxide and a crystalline structure of MgO under XRD crystallography, and retains these crystalline structures over subsequent redox cycles. In an embodiment, the metal oxide is Fe.sub.2O.sub.3, and the gaseous hydrocarbon is comprised of methane.

  9. Multiscale Modeling of a Packed Bed Chemical Looping Reforming (PBCLR Reactor

    Directory of Open Access Journals (Sweden)

    Arpit Singhal

    2017-12-01

    Full Text Available Packed bed reactors are broadly used in industry and are under consideration for novel reactor concepts such as packed bed chemical looping reforming (PBCLR. Mass and heat transfer limitations in and around the particles in packed bed reactors strongly affect the behavior of these units. This study employs a multiscale modeling methodology to simulate a PBCLR reactor. Specifically, small-scale particle-resolved direct numerical simulation is utilized to improve large-scale mass transfer models for use in an industrial scale 1D model. Existing intra-particle mass transfer models perform well for simple first order reactions, but several model enhancements were required to model the more complex steam methane reforming reaction system. Three specific aspects required enhanced modeling: the generation of additional gas volume by the reforming reactions, the lack of clear reaction orders in the equilibrium reactions, and the diffusion of multiple reactant species into the particle. Large-scale simulations of the PBCLR reactor with the enhanced 1D model showed that the highly reactive Ni-based catalyst/oxygen carrier employed allows for the use of large particle sizes and high gas flowrates, offering potential for process intensification.

  10. Modeling of Supersonic Combustion Systems for Sustained Hypersonic Flight

    Directory of Open Access Journals (Sweden)

    Stephen M. Neill

    2017-11-01

    Full Text Available Through Computational Fluid Dynamics and validation, an optimal scramjet combustor has been designed based on twin-strut Hydrogen injection to sustain flight at a desired speed of Mach 8. An investigation undertaken into the efficacy of supersonic combustion through various means of injection saw promising results for Hydrogen-based systems, whereby strut-style injectors were selected over transverse injectors based on their pressure recovery performance and combustive efficiency. The final configuration of twin-strut injectors provided robust combustion and a stable region of net thrust (1873 kN in the nozzle. Using fixed combustor inlet parameters and injection equivalence ratio, the finalized injection method advanced to the early stages of two-dimensional (2-D and three-dimensional (3-D scramjet engine integration. The overall investigation provided a feasible supersonic combustion system, such that Mach 8 sustained cruise could be achieved by the aircraft concept in a computational design domain.

  11. Practical approaches to field problems of stationary combustion systems

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.W. [Natural Resources Canada, Ottawa (Canada)

    1997-09-01

    The CANMET Energy Technology Centre (CETC) business plan dictates collaboration with industrial clients and other government agencies to promote energy efficiency, health and safety, pollution reduction and productivity enhancement. The Advanced Combustion Technologies group of CETC provides consultation to numerous organizations in combustion related areas by conducting laboratory and field investigations of fossil fuel-fired combustion equipment. CETC, with its modern research facilities and technical expertise, has taken this practical approach since the seventies and has assisted many organizations in overcoming field problems and in providing cost saving measures and improved profit margins. This paper presents a few selected research projects conducted for industrial clients in north and central America. The combustion systems investigated are mostly liquid fuel fired, with the exception of the utility boiler which was coal-fired. The key areas involved include fuel quality, fuel storage/delivery system contamination, waste derived oils, crude oil combustion, unacceptable pollutant emissions, ambient soot deposition, slagging, fouling, boiler component degradation, and particulate characterization. Some of the practical approaches taken to remedy these field problems on several combustion systems including residential, commercial and industrial scale units are discussed.

  12. An Integrated Photoelectrochemical-Chemical Loop for Solar-Driven Overall Splitting of Hydrogen Sulfide

    DEFF Research Database (Denmark)

    Zong, Xu; Han, Jingfeng; Seger, Brian

    2014-01-01

    Abundant and toxic hydrogen sulfide (H2S) from industry and nature has been traditionally considered a liability. However, it represents a potential resource if valuable H-2 and elemental sulfur can be simultaneously extracted through a H2S splitting reaction. Herein a photochemical-chemical loop...

  13. Different Methods of Manufacturing Fe-Based Oxygen Carrier Particles for Reforming Via Chemical Looping, and Their Effect on Performance

    Science.gov (United States)

    Cleeton, J. P. E.; Bonn, C. D.; Müller, C. R.; Dennis, J. S.; Scott, S. A.

    Chemical looping combustion (CLC) is a means of combusting carbonaceous fuels, which inherently separates the greenhouse gas carbon dioxide from the remaining combustion products, and has the potential to be used for the production of high-purity hydrogen. Iron-based oxygen carriers for CLC have been subject to considerable work; however, there are issues regarding the lifespan of iron-based oxygen carriers over repeated cycles. In this work, haematite (Fe2O3) was reduced in an N2+CO+CO2 mixture within a fluidised bed at 850°C, and oxidised back to magnetite (Fe3O4) in a H2O+N2 mixture, with the subsequent yield of hydrogen during oxidation being of interest. Subsequent cycles started from Fe3O4 and two transition regimes were studied; Fe3O4↔Fe0.947O and Fe3O4↔Fe. Particles were produced by mechanical mixing and co-precipitation. In the case of co-precipitated particles, Al was added such that the ratio of Fe:Al by weight was 9:1, and the final pH of the particles during precipitation was investigated for its subsequent effect on reactivity. This paper shows that co-precipitated particles containing additives such as Al may be able to achieve consistently high H2 yields when cycling between Fe3O4 and Fe, and that these yields are a function of the ratio of [CO2] to [CO] during reduction, where thermodynamic arguments suggest that the yield should be independent of this ratio. A striking feature with our materials was that particles made by mechanical mixing performed much better than those made by co-precipitation when cycling between Fe3O4 and Fe0.947O, but much worse than co-precipitated particles when cycling between Fe3O4 and Fe.

  14. Corrosion performance of materials for advanced combustion systems

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.; Yanez-Herrero, M.; Fornasieri, C.

    1993-12-01

    Conceptual designs of advanced combustion systems that utilize coal as a feedstock require high-temperature furnaces and heat transfer surfaces capable of operating at more elevated temperatures than those prevalent in current coal-fired power plants. The combination of elevated temperatures and hostile combustion environments necessitates development/application of advanced ceramic materials in these designs. This report characterizes the chemistry of coal-fired combustion environments over the wide temperature range that is of interest in these systems and discusses preliminary experimental results on several materials (alumina, Hexoloy, SiC/SiC, SiC/Si{sub 3}N{sub 4}/Si{sub 3}N{sub 4}, ZIRCONIA, INCONEL 677 and 617) with potential for application in these systems.

  15. A sustained-arc ignition system for internal combustion engines

    Science.gov (United States)

    Birchenough, A. G.

    1977-01-01

    A sustained-arc ignition system was developed for internal combustion engines. It produces a very-long-duration ignition pulse with an energy in the order of 100 millijoules. The ignition pulse waveform can be controlled to predetermined actual ignition requirements. The design of the sustained-arc ignition system is presented in the report.

  16. Apparatus and method for gas turbine active combustion control system

    Science.gov (United States)

    Umeh, Chukwueloka (Inventor); Kammer, Leonardo C. (Inventor); Shah, Minesh (Inventor); Fortin, Jeffrey B. (Inventor); Knobloch, Aaron (Inventor); Myers, William J. (Inventor); Mancini, Alfred Albert (Inventor)

    2011-01-01

    An Active Combustion Control System and method provides for monitoring combustor pressure and modulating fuel to a gas turbine combustor to prevent combustion dynamics and/or flame extinguishments. The system includes an actuator, wherein the actuator periodically injects pulsed fuel into the combustor. The apparatus also includes a sensor connected to the combustion chamber down stream from an inlet, where the sensor generates a signal detecting the pressure oscillations in the combustor. The apparatus controls the actuator in response to the sensor. The apparatus prompts the actuator to periodically inject pulsed fuel into the combustor at a predetermined sympathetic frequency and magnitude, thereby controlling the amplitude of the pressure oscillations in the combustor by modulating the natural oscillations.

  17. Annual Report: DOE Advanced Combustion Systems & Fuels R&D; Light-Duty Diesel Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Busch, Stephen [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2017-11-01

    Despite compliance issues in previous years, automakers have demonstrated that the newest generation of diesel power trains are capable of meeting all federal and state regulations (EPA, 2016). Diesels continue to be a cost-effective, efficient, powerful propulsion source for many light- and medium-duty vehicle applications (Martec, 2016). Even modest reductions in the fuel consumption of light- and medium duty diesel vehicles in the U.S. will eliminate millions of tons of CO2 emissions per year. Continued improvement of diesel combustion systems will play an important role in reducing fleet fuel consumption, but these improvements will require an unprecedented scientific understanding of how changes in engine design and calibration affect the mixture preparation, combustion, and pollutant formation processes that take place inside the cylinder. The focus of this year’s research is to provide insight into the physical mechanisms responsible for improved thermal efficiency observed with a stepped-lip piston. Understanding how piston design can influence efficiency will help engineers develop and optimize new diesel combustion systems.

  18. Secondary air systems for improved residential wood stove combustion

    Energy Technology Data Exchange (ETDEWEB)

    Poirot, R.L.; Sanborn, C.R.

    1982-12-21

    Three wood burning stoves were modified by the addition of preheated secondary air systems to keep burn volatile gases given off during the initial stage of combustion. This report describes the modifications and the performance of the stoves after modification. Stoves tested during the year's study included a Jotul 118, a Garrison IV and a Hearthstone I. After modification, total particulate emissions decreased in the three stoves by 56%, 69% and 4%, respectively. Flue gas CO/sub 2/ (a by-product of combustion and an indicator of the completeness of combustion) increased by 15%, 15% and 17%, respectively. Temperatures in the secondary combustion zones increased by 17%, 50% and 6%. On the basis of these measurements, other internal temperatures and visual observations, we believe the modifications significantly increased the combustion efficiencies of the Jotul and the Garrison. No improvement was discerned in the Hearthstone's performance (possibly due to unrealistic burn rate compared to firebox size). The design concepts developed, refined and tested under this year's study should be readily applicable to the majority of residential wood stoves on the market.

  19. Radiative heat transfer in turbulent combustion systems theory and applications

    CERN Document Server

    Modest, Michael F

    2016-01-01

    This introduction reviews why combustion and radiation are important, as well as the technical challenges posed by radiation. Emphasis is on interactions among turbulence, chemistry and radiation (turbulence-chemistry-radiation interactions – TCRI) in Reynolds-averaged and large-eddy simulations. Subsequent chapters cover: chemically reacting turbulent flows; radiation properties, Reynolds transport equation (RTE) solution methods, and TCRI; radiation effects in laminar flames; TCRI in turbulent flames; and high-pressure combustion systems. This Brief presents integrated approach that includes radiation at the outset, rather than as an afterthought. It stands as the most recent developments in physical modeling, numerical algorithms, and applications collected in one monograph.

  20. Combustion reaction of Ti–Al–C–N system

    Indian Academy of Sciences (India)

    The combustion reaction of Ti–Al–C–N system was investigated by using Ti powders and one CN precursor powder as reactant powder blends. The reactant powder blends ... Mu1 Baoyan Liang1. Materials and Chemical Engineering School, Zhongyuan University of Technology, Zhengzhou 450007, Henan, P.R. China ...

  1. Combustion reaction of Ti–Al–C–N system

    Indian Academy of Sciences (India)

    Abstract. The combustion reaction of Ti–Al–C–N system was investigated by using Ti powders and one CNx precursor powder as reactant powder blends. The reactant powder blends ratio was adjusted to obtain different materials. The phase composition of the samples was investigated by X-ray diffraction (XRD).

  2. Solid-Fueled Pressurized Chemical Looping with Flue-Gas Turbine Combined Cycle for Improved Plant Efficiency and CO2 Capture

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Kunlei [Univ. of Kentucky, Lexington, KY (United States); Chen, Liangyong [Univ. of Kentucky, Lexington, KY (United States); Zhang, Yi [Univ. of Kentucky, Lexington, KY (United States); Richburg, Lisa [Univ. of Kentucky, Lexington, KY (United States); Simpson, James [WorleyParsons Group Inc., Reading, PA (United States); White, Jay [WorleyParsons Group Inc., Reading, PA (United States); Rossi, Gianalfredo [WorleyParsons Group Inc., Reading, PA (United States)

    2013-12-31

    The purpose of this document is to report the final result of techno-economic analysis for the proposed 550MWe integrated pressurized chemical looping combustion combined cycle process. An Aspen Plus based model is delivered in this report along with the results from three sensitivity scenarios including the operating pressure, excess air ratio and oxygen carrier performance. A process flow diagram and detailed stream table for the base case are also provided with the overall plant energy balance, carbon balance, sulfur balance and water balance. The approach to the process and key component simulation are explained. The economic analysis (OPEX and CAPX) on four study cases via DOE NETL Reference Case 12 are presented and explained.

  3. Fluid structure interaction to predict liner vibrations in an industrial combustion system

    NARCIS (Netherlands)

    Huls, R.A.; van Kampen, J.F.; Kok, Jacobus B.W.; de Boer, Andries; Nilsson, A.; Boden, H.

    2003-01-01

    To decrease NOx emissions from a combustion system lean premixed combustion in combination with an annular combustor is used. The disadvantage is that sound pressure levels in the combustion system become higher which excite the liner (the surrounding structure). This limits the life of the

  4. Combustion chemical vapor desposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States)

    1995-10-01

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings.

  5. Advanced radiant combustion system. Final report, September 1989--September 1996

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, J.D.; Carswell, M.G.; Long, F.S.

    1996-09-01

    Results of the Advanced Radiant Combustion System (ARCS) project are presented in this report. This work was performed by Alzeta Corporation as prime contractor under a contract to the U.S. Department of Energy Office of Industrial Technologies as part of a larger DOE program entitled Research Program for Advanced Combustion Systems. The goals of the Alzeta ARCS project were to (a) Improve the high temperature performance characteristics of porous surface ceramic fiber burners, (b) Develop an Advanced Radiant Combustion System (ARCS) that combines combustion controls with an advanced radiant burner, and (c) Demonstrate the advanced burner and controls in an industrial application. Prior to the start of this project, Alzeta had developed and commercialized a porous surface radiant burner, the Pyrocore{trademark} burner. The product had been commercially available for approximately 5 years and had achieved commercial success in a number of applications ranging from small burners for commercial cooking equipment to large burners for low temperature industrial fluid heating applications. The burner was not recommended for use in applications with process temperatures above 1000{degrees}F, which prevented the burner from being used in intermediate to high temperature processes in the chemical and petroleum refining industries. The interest in increasing the maximum use temperature of the burner was motivated in part by a desire to expand the number of applications that could use the Pyrocore product, but also because many of the fluid sensitive heating applications of interest would benefit from the distributed flux characteristic of porous surface burners. Background information on porous surface radiant burners, and a discussion of advantages that would be provided by an improved product, are presented in Section 2.

  6. Coal Direct Chemical Looping Retrofit to Pulverized Coal Power Plants for In-Situ CO2 Capture

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Liang; Li, Fanxing; Kim, Ray; Bayham, Samuel; McGiveron, Omar; Tong, Andrew; Connell, Daniel; Luo, Siwei; Sridhar, Deepak; Wang, Fei; Sun, Zhenchao; Fan, Liang-Shih

    2013-09-30

    A novel Coal Direct Chemical Looping (CDCL) system is proposed to effectively capture CO2 from existing PC power plants. The work during the past three years has led to an oxygen carrier particle with satisfactory performance. Moreover, successful laboratory, bench scale, and integrated demonstrations have been performed. The proposed project further advanced the novel CDCL technology to sub-pilot scale (25 kWth). To be more specific, the following objectives attained in the proposed project are: 1. to further improve the oxygen carrying capacity as well as the sulfur/ash tolerance of the current (working) particle; 2. to demonstrate continuous CDCL operations in an integrated mode with > 99% coal (bituminous, subbituminous, and lignite) conversion as well as the production of high temperature exhaust gas stream that is suitable for steam generation in existing PC boilers; 3. to identify, via demonstrations, the fate of sulfur and NOx; 4. to conduct thorough techno-economic analysis that validates the technical and economical attractiveness of the CDCL system. The objectives outlined above were achieved through collaborative efforts among all the participants. CONSOL Energy Inc. performed the techno-economic analysis of the CDCL process. Shell/CRI was able to perform feasibility and economic studies on the large scale particle synthesis and provide composite particles for the sub-pilot scale testing. The experience of B&W (with boilers) and Air Products (with handling gases) assisted the retrofit system design as well as the demonstration unit operations. The experience gained from the sub-pilot scale demonstration of the Syngas Chemical Looping (SCL) process at OSU was able to ensure the successful handling of the solids. Phase 1 focused on studies to improve the current particle to better suit the CDCL operations. The optimum operating conditions for the reducer reactor such as the temperature, char gasification enhancer type, and flow rate were identified. The

  7. 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.

  8. Design of a High Intensity Turbulent Combustion System

    Science.gov (United States)

    2015-05-01

    the product. When all the carbons in the fuel converts into carbon dioxide (CO2) and all the hydrogen forms water (H20) then the combustion process...spark plug. The detail of the experiments are described in the later chapters. Although most of the hydrocarbon combustion produces carbon dioxide (CO2...combustion of carbon monoxide with 30 steps among 11 species, methane, methanol , ethane, ethylene, and acetylene combustion with 134 steps among 30

  9. Canadian R&D on oil-fired combustion systems

    Energy Technology Data Exchange (ETDEWEB)

    Hayden, A.C.S.; Entchev, E. [CCRL/ERL/CANMET, Ottawa (Canada)

    1996-07-01

    This paper describes research and development presently being conducted on oil-fired space and tap water heating systems by the Advanced Combustion Technology Group, CCRL/ERL/CANMET, in Ottawa, Canada. The presentation will focus on R&D activities at CCRL in support of the Canadian Oil Heat Association (COHA) and of the energy policy initiatives of Natural Resources Canada. Progress will be reported on activities to develop suitable oil-fired integrated systems to satisfy the low energy demands of new homes. The utilization of fuzzy logic-based control heating systems including fan coils for a complete range of old and new North American housing will be discussed. Additional activities to be discussed in the presentation will relate to the development of appropriate seasonal efficiency standards for complex integrated space/water heating systems, as well as an evaluation of alternative sidewall venting technologies and their implications for seasonal energy efficiency.

  10. Stagnation point reverse flow combustor for a combustion system

    Science.gov (United States)

    Zinn, Ben T. (Inventor); Neumeier, Yedidia (Inventor); Seitzman, Jerry M. (Inventor); Jagoda, Jechiel (Inventor); Hashmonay, Ben-Ami (Inventor)

    2007-01-01

    A combustor assembly includes a combustor vessel having a wall, a proximate end defining an opening and a closed distal end opposite said proximate end. A manifold is carried by the proximate end. The manifold defines a combustion products exit. The combustion products exit being axially aligned with a portion of the closed distal end. A plurality of combustible reactant ports is carried by the manifold for directing combustible reactants into the combustion vessel from the region of the proximate end towards the closed distal end.

  11. Exhaust gas recirculation system for an internal combustion engine

    Science.gov (United States)

    Wu, Ko-Jen

    2013-05-21

    An exhaust gas recirculation system for an internal combustion engine comprises an exhaust driven turbocharger having a low pressure turbine outlet in fluid communication with an exhaust gas conduit. The turbocharger also includes a low pressure compressor intake and a high pressure compressor outlet in communication with an intake air conduit. An exhaust gas recirculation conduit fluidly communicates with the exhaust gas conduit to divert a portion of exhaust gas to a low pressure exhaust gas recirculation branch extending between the exhaust gas recirculation conduit and an engine intake system for delivery of exhaust gas thereto. A high pressure exhaust gas recirculation branch extends between the exhaust gas recirculation conduit and the compressor intake and delivers exhaust gas to the compressor for mixing with a compressed intake charge for delivery to the intake system.

  12. 46 CFR 62.35-35 - Starting systems for internal-combustion engines.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Starting systems for internal-combustion engines. 62.35-35 Section 62.35-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE... Starting systems for internal-combustion engines. The starting systems for propulsion engines and for prime...

  13. Ignition system for internal-combustion engines negative bias trigger

    Energy Technology Data Exchange (ETDEWEB)

    Alexeev, A.N.; Zhmurin, I.I.; Moskovsky, A.A.; Oparin, I.M.; Cheplanov, V.I.; Sokolin, L.S.; Zolotarevsky, V.S.; Zolotarevskaya, A.M.; Zolotarevskaya, M.V.

    1977-07-26

    An internal-combustion engine ignition system comprises a power source with a voltage stabilizer; a compacitor connected to the power source through a rectifier; several circuits connected in parallel with the capacitor and ignition coil primary windings and thyristors. To the control gate of each of the thyristors is connected a control circuit with a control pulse generator. Also connected to the thyristor control gates is an arrangement for applying a negative bias to the control gates. This arrangement is in the form of a diode whose anode is connected to the cathode of each of the thyristors, whereas the cathode of said diode is connected to the capacitor and is also connected through isolation diodes to the control gate of each of the thyristors.

  14. Multiple fuel supply system for an internal combustion engine

    Science.gov (United States)

    Crothers, William T.

    1977-01-01

    A multiple fuel supply or an internal combustion engine wherein phase separation of components is deliberately induced. The resulting separation permits the use of a single fuel tank to supply components of either or both phases to the engine. Specifically, phase separation of a gasoline/methanol blend is induced by the addition of a minor amount of water sufficient to guarantee separation into an upper gasoline phase and a lower methanol/water phase. A single fuel tank holds the two-phase liquid with separate fuel pickups and separate level indicators for each phase. Either gasoline or methanol, or both, can be supplied to the engine as required by predetermined parameters. A fuel supply system for a phase-separated multiple fuel supply contained in a single fuel tank is described.

  15. Combustion systems and power plants incorporating parallel carbon dioxide capture and sweep-based membrane separation units to remove carbon dioxide from combustion gases

    Science.gov (United States)

    Wijmans, Johannes G [Menlo Park, CA; Merkel, Timothy C [Menlo Park, CA; Baker, Richard W [Palo Alto, CA

    2011-10-11

    Disclosed herein are combustion systems and power plants that incorporate sweep-based membrane separation units to remove carbon dioxide from combustion gases. In its most basic embodiment, the invention is a combustion system that includes three discrete units: a combustion unit, a carbon dioxide capture unit, and a sweep-based membrane separation unit. In a preferred embodiment, the invention is a power plant including a combustion unit, a power generation system, a carbon dioxide capture unit, and a sweep-based membrane separation unit. In both of these embodiments, the carbon dioxide capture unit and the sweep-based membrane separation unit are configured to be operated in parallel, by which we mean that each unit is adapted to receive exhaust gases from the combustion unit without such gases first passing through the other unit.

  16. Energy Efficient Engine (E3) combustion system component technology performance report

    Science.gov (United States)

    Burrus, D. L.; Chahrour, C. A.; Foltz, H. L.; Sabla, P. E.; Seto, S. P.; Taylor, J. R.

    1984-01-01

    The Energy Efficient Engine (E3) combustor effort was conducted as part of the overall NASA/GE E3 Program. This effort included the selection of an advanced double-annular combustion system design. The primary intent of this effort was to evolve a design that meets the stringent emissions and life goals of the E3, as well as all of the usual performance requirements of combustion systems for modern turbofan engines. Numerous detailed design studies were conducted to define the features of the combustion system design. Development test hardware was fabricated, and an extensive testing effort was undertaken to evaluate the combustion system subcomponents in order to verify and refine the design. Technology derived from this effort was incorporated into the engine combustion hardware design. The advanced engine combustion system was then evaluated in component testing to verify the design intent. What evolved from this effort was an advanced combustion system capable of satisfying all of the combustion system design objectives and requirements of the E3.

  17. Advanced Materials for Mercury 50 Gas Turbine Combustion System

    Energy Technology Data Exchange (ETDEWEB)

    Price, Jeffrey

    2008-09-30

    Solar Turbines Incorporated (Solar), under cooperative agreement number DE-FC26-0CH11049, has conducted development activities to improve the durability of the Mercury 50 combustion system to 30,000 hours life and reduced life cycle costs. This project is part of Advanced Materials in the Advanced Industrial Gas Turbines program in DOE's Office of Distributed Energy. The targeted development engine was the Mercury{trademark} 50 gas turbine, which was developed by Solar under the DOE Advanced Turbine Systems program (DOE contract number DE-FC21-95MC31173). As a generator set, the Mercury 50 is used for distributed power and combined heat and power generation and is designed to achieve 38.5% electrical efficiency, reduced cost of electricity, and single digit emissions. The original program goal was 20,000 hours life, however, this goal was increased to be consistent with Solar's standard 30,000 hour time before overhaul for production engines. Through changes to the combustor design to incorporate effusion cooling in the Generation 3 Mercury 50 engine, which resulted in a drop in the combustor wall temperature, the current standard thermal barrier coated liner was predicted to have 18,000 hours life. With the addition of the advanced materials technology being evaluated under this program, the combustor life is predicted to be over 30,000 hours. The ultimate goal of the program was to demonstrate a fully integrated Mercury 50 combustion system, modified with advanced materials technologies, at a host site for a minimum of 4,000 hours. Solar was the Prime Contractor on the program team, which includes participation of other gas turbine manufacturers, various advanced material and coating suppliers, nationally recognized test laboratories, and multiple industrial end-user field demonstration sites. The program focused on a dual path development route to define an optimum mix of technologies for the Mercury 50 and future gas turbine products. For liner and

  18. Hydrodynamic analysis of a three-fluidized bed reactor cold flow model for chemical looping hydrogen generation. Pressure characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Zhipeng; Xiang, Wenguo; Chen, Shiyi; Wang, Dong [Southeast Univ., Nanjing (China). School of Energy and Environment

    2013-07-01

    Chemical looping hydrogen generation (CLHG) can produce pure hydrogen with inherent separation of CO{sub 2} from fossils fuel. The process involves a metal oxide, as an oxygen carrier, such as iron oxide. The CLHG system consists of three reactors: a fuel reactor (FR), a steam reactor (SR) and an air reactor (AR). In the FR, the fuel gases react with iron oxides (hematite Fe{sub 2}O{sub 3}, magnetite Fe{sub 3}O{sub 4}, wuestite FeO), generating reduced iron oxides (FeO or even Fe), and with full conversion of gaseous fuels, pure CO{sub 2} can be obtained after cooling the flue gas from the fuel reactor; in the SR, FeO and Fe reacts with steam to generate magnetite (Fe{sub 3}O{sub 4}) and H{sub 2}, the latter representing the final target product of the process; in the AR, the magnetite is oxidized back to hematite which is used in another cycle. A cold flow model of three-fluidized bed for CLHG corresponding to 50 KW hot units has been built. A major novelty of this facility is the compact fuel reactor, which integrates a bubble and a fast fluidized bed to avoid the incomplete conversion of the fuel gas caused by the thermodynamics equilibrium. In order to study the pressure characteristics and the solids concentration of the system, especially in the fuel reactor, the gas velocity of three reactors, gas flow of L-type value, total solids inventory (TSI) and the secondary air of fuel reactor were varied. Results show that the pressure and the solids concentration are strongly influenced by the fluidizing-gas velocity of three reactors. Moreover, the entrainment of the upper part of fuel reactor increases as the total solids inventory increases, and the operating range of the FR can be changed by introducing secondary air or increasing the total solids inventory.

  19. Hydrogen from ethanol reforming with aqueous fraction of pine pyrolysis oil with and without chemical looping.

    Science.gov (United States)

    Zin, R Md; Ross, A B; Jones, J M; Dupont, V

    2015-01-01

    Reforming ethanol ('EtOH') into hydrogen rich syngas using the aqueous fraction from pine bio-oil ('AQ') as a combined source of steam and supplementary organic feed was tested in packed bed with Ni-catalysts 'A' (18wt%/α-Al2O3) and 'B' (25wt%/γ-Al2O3). The catalysts were initially pre-reduced by H2, but this was followed by a few cycles of chemical looping steam reforming, where the catalysts were in turn oxidised in air and auto-reduced by the EtOH/AQ mixture. At 600°C, EtOH/AQ reformed similarly to ethanol for molar steam to carbon ratios (S/C) between 2 and 5 on the H2-reduced catalysts. At S/C of 3.3, 90% of the carbon feed converted on catalyst A to CO2 (58%), CO (30%) and CH4 (2.7%), with 17wt% H2 yield based on dry organic feedstock, equivalent to 78% of the equilibrium value. Catalyst A maintained these outputs for four cycles while B underperformed due to partial reduction. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Chemical looping dry reforming as novel, intensified process for CO{sub 2} activation

    Energy Technology Data Exchange (ETDEWEB)

    Bhavsar, S. [University of Pittsburgh, Swanson School of Engineering, Chemical Engineering Department, Pittsburgh, PA (United States); U.S. Department of Energy, National Energy Technology Laboratory, Pittsburgh, PA (United States); Najera, M. [University of Pittsburgh, Swanson School of Engineering, Chemical Engineering Department, Pittsburgh, PA (United States); University of Pittsburgh, Mascaro Center for Sustainable Innovation, Pittsburgh, PA (United States); Veser, G. [University of Pittsburgh, Swanson School of Engineering, Chemical Engineering Department, Pittsburgh, PA (United States); U.S. Department of Energy, National Energy Technology Laboratory, Pittsburgh, PA (United States); University of Pittsburgh, Mascaro Center for Sustainable Innovation, Pittsburgh, PA (United States)

    2012-07-15

    Chemical looping dry reforming (CLDR) is a novel, intensified route for CO{sub 2} activation. Two nanostructured carriers (Fe-BHA and Fe rate at SiO{sub 2}) are synthesized, characterized, and evaluated with regard to activity and stability in thermogravimetric and fixed-bed CLDR reactor studies over a temperature range of 500-800 C. Fe-barium hexaaluminate (Fe-BHA) shows fast redox kinetics and stable operation over multiple CLDR cycles, while Fe rate at SiO{sub 2} exhibits poor activity for CO generation due to a partial loss of the core-shell structure and formation of silicates. While the latter could be removed via a two-step oxidation scheme, carrier utilization remained well below that of Fe-BHA (51 % versus 15 %). However, the two-step oxidation configuration turns the net endothermic CLDR process into a net exothermic process, opening up a highly efficient autothermal process alternative. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Combustion Research Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Combustion Research Laboratory facilitates the development of new combustion systems or improves the operation of existing systems to meet the Army's mission for...

  2. Prediction of limit cycle pressure oscillations in gas turbine combustion systems using the flame describing function

    NARCIS (Netherlands)

    Krediet, H.J.

    2012-01-01

    Thermo-acoustic analysis is crucial for a successful development of new gas turbine combustion systems. In this context, it becomes more and more necessary to predict the limit cycle pressure amplitude of thermo-acoustic combustion instabilities to figure out if they are within the critical design

  3. Detection and control of combustion instability based on the concept of dynamical system theory

    Science.gov (United States)

    Gotoda, Hiroshi; Shinoda, Yuta; Kobayashi, Masaki; Okuno, Yuta; Tachibana, Shigeru

    2014-02-01

    We propose an online method of detecting combustion instability based on the concept of dynamical system theory, including the characterization of the dynamic behavior of combustion instability. As an important case study relevant to combustion instability encountered in fundamental and practical combustion systems, we deal with the combustion dynamics close to lean blowout (LBO) in a premixed gas-turbine model combustor. The relatively regular pressure fluctuations generated by thermoacoustic oscillations transit to low-dimensional intermittent chaos owing to the intermittent appearance of burst with decreasing equivalence ratio. The translation error, which is characterized by quantifying the degree of parallelism of trajectories in the phase space, can be used as a control variable to prevent LBO.

  4. Capture of CO{sub 2} in Coal Combustion (CCCC)

    Energy Technology Data Exchange (ETDEWEB)

    Mattisson, T.; Abanades, J.C.; Lyngfelt, A.; Abad, A.; Johansson, M.; Adanez, J.; Garcia-Labiano, F.; Diego, L.F. de; Gayan, P.; Kronberger, B.; Hofbauer, H.; Luisser, M.; Palacios, J.M.; Alvares, D.; Grasa, G.; Oakey, J.; Arias, B.; Orjala, M.; Heiskanen, V.P.

    2005-10-15

    The aim of the project is to develop processes for carbon dioxide capture from coal-fired power plants with small energy penalties. Two novel processes are studied: chemical-looping combustion (CLC) and the lime carbonation/calcination cycle (LCCC). Both parts of the project have been highly successful. With respect to CLC the process was a paper concept when the project started, never tested in actual operation. In this project a large number of oxygen carriers have been produced and tested and many were found to have suitable properties for the process. A small reactor system for chemical-looping combustion was developed, tested and found to be working well with three different oxygen carriers. Furthermore cold-flow models indicate the realism of the process in full scale. The kinetics of a limited number of particles has been studied in detail, and modelling shows that the solids inventories needed will be small. With respect to the LCCC part, some of the options investigated can be potentially competitive to capture CO{sub 2} in coal-based power generation and cement plants. The observed decay in capture capacity of the sorbent can be compensated with a large make up flow of fresh limestone due to its low price. The key reactor systems (carbonator and calciner) have shown no major barriers for continuous operation All the options studied have the inherent advantage of low efficiency penalties. For some options, no major technical barriers have been identified and confidence has been built on the operation and understanding of individual units. Some of the options are ready to be demonstrated at large pilot level in a continuous power plant.

  5. Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO2 Capture

    Energy Technology Data Exchange (ETDEWEB)

    Kathe, Mandar [Ohio State University, Columbus, OH (United States); Xu, Dikai [Ohio State University, Columbus, OH (United States); Hsieh, Tien-Lin [Ohio State University, Columbus, OH (United States); Simpson, James [Ohio State University, Columbus, OH (United States); Statnick, Robert [Ohio State University, Columbus, OH (United States); Tong, Andrew [Ohio State University, Columbus, OH (United States); Fan, Liang-Shih [Ohio State University, Columbus, OH (United States)

    2014-12-31

    This document is the final report for the project titled “Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO2 Capture” under award number FE0012136 for the performance period 10/01/2013 to 12/31/2014.This project investigates the novel Ohio State chemical looping gasification technology for high efficiency, cost efficiency coal gasification for IGCC and methanol production application. The project developed an optimized oxygen carrier composition, demonstrated the feasibility of the concept and completed cold-flow model studies. WorleyParsons completed a techno-economic analysis which showed that for a coal only feed with carbon capture, the OSU CLG technology reduced the methanol required selling price by 21%, lowered the capital costs by 28%, increased coal consumption efficiency by 14%. Further, using the Ohio State Chemical Looping Gasification technology resulted in a methanol required selling price which was lower than the reference non-capture case.

  6. Computational Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Westbrook, C K; Mizobuchi, Y; Poinsot, T J; Smith, P J; Warnatz, J

    2004-08-26

    Progress in the field of computational combustion over the past 50 years is reviewed. Particular attention is given to those classes of models that are common to most system modeling efforts, including fluid dynamics, chemical kinetics, liquid sprays, and turbulent flame models. The developments in combustion modeling are placed into the time-dependent context of the accompanying exponential growth in computer capabilities and Moore's Law. Superimposed on this steady growth, the occasional sudden advances in modeling capabilities are identified and their impacts are discussed. Integration of submodels into system models for spark ignition, diesel and homogeneous charge, compression ignition engines, surface and catalytic combustion, pulse combustion, and detonations are described. Finally, the current state of combustion modeling is illustrated by descriptions of a very large jet lifted 3D turbulent hydrogen flame with direct numerical simulation and 3D large eddy simulations of practical gas burner combustion devices.

  7. Reforming Technologies to Improve the Performance of Combustion Systems

    Directory of Open Access Journals (Sweden)

    Hashim Hassan

    2014-09-01

    Full Text Available A large number of theoretical and experimental studies have shown that the performance of kerosene combustion increases significantly if combustion is being assisted by the addition of hydrogen to the fuel/air mixture during the combustion process. It reduces the amount of CO, CO2 and NOx emissions, while increasing the flame stability limits. It also helps in bruning fuel/air mixtures at much leaner equivalence ratios. The same principle could be applied to gain benefits in gas turbine combustors. Hydrogen for this purpose could be produced by the reforming of hydrocarbon fuels using a reformer module. This paper presents key hydrogen reforming technologies which, by implementation in gas turbine combustors, hold potential for improving both their performance and service life.

  8. Transformations of inorganic coal constituents in combustion systems

    Energy Technology Data Exchange (ETDEWEB)

    Helble, J.J. (ed.); Srinivasachar, S.; Wilemski, G.; Boni, A.A. (PSI Technology Co., Andover, MA (United States)); Kang, Shin-Gyoo; Sarofim, A.F.; Graham, K.A.; Beer, J.M. (Massachusetts Inst. of Tech., Cambridge, MA (United States)); Peterson, T.W.; Wendt, J.O.L.; Gallagher, N.B.; Bool, L. (Arizona Univ., Tucson, AZ (United States)); Huggins, F.E.; Huffman, G.P.; Shah, N.; Shah, A. (Kentucky Univ., Lexingt

    1992-11-01

    Results from an experimental investigation of the mechanisms governing the ash aerosol size segregated composition resulting from the combustion of pulverized coal in a laboratory scale down-flow combustor are described. The results of modeling activities used to interpret the results of the experiments conducted under his subtask are also described in this section. Although results from the entire program are included, Phase II studies which emphasized: (1) alkali behavior, including a study of the interrelationship between potassium vaporization and sodium vaporization; and (2) iron behavior, including an examination of the extent of iron-aluminosilicate interactions, are highlighted. Idealized combustion determination of ash particle formation and surface stickiness are also described.

  9. Automotive Thermoelectric Generator impact on the efficiency of a drive system with a combustion engine

    OpenAIRE

    Ziolkowski Andrzej

    2017-01-01

    Increasing the combustion engine drive systems efficiency is currently being achieved by structural changes in internal combustion engines and its equipment, which are geared towards limiting mechanical, thermal and outlet losses. For this reason, downsizing. In addition to these changes, all manner of exhaust gas energy recovery systems are being investigated and implemented, including turbocompound, turbogenerators and thermoelectric generators. The article presents the author’s idea of a t...

  10. Transition of the Combustion of Condensed Systems into an Explosion

    Science.gov (United States)

    1975-02-06

    the channel of not change in proportion to an coen core i.- iticn (mixec cowder, c=l atm., d= propag7ation. The remarkable characteristic of a blind...Figure 106. Dependence of the rate of combustion of mixture ZhVV on pressure [186]: 1 - nitric acid (99%) - nitro- ethane ; 2 - nitric acid (99%) - nitro

  11. LES SOFTWARE FOR THE DESIGN OF LOW EMISSION COMBUSTION SYSTEMS FOR VISION 21 PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Clifford Smith

    2003-09-01

    Application and testing of the new combustion Large Eddy Simulation (LES) code for the design of advanced gaseous combustion systems is described in this 12th quarterly report. In this quarter, continued validation and testing of the combustion LES code was performed for the DOE-SimVal combustor. Also, beta testing by six consortium members was performed for various burner and combustor configurations. A list of suggested code improvements by the beta testers was itemized. Work will continue in FY04. A conditional modification to the contract will be granted. The additional work will focus on modeling/analyzing the SimVal experiments.

  12. Chemical looping fluidized-bed concentrating solar power system and method

    Science.gov (United States)

    Ma, Zhiwen

    2017-07-11

    A concentrated solar power (CSP) plant comprises a receiver configured to contain a chemical substance for a chemical reaction and an array of heliostats. Each heliostat is configured to direct sunlight toward the receiver. The receiver is configured to transfer thermal energy from the sunlight to the chemical substance in a reduction reaction. The CSP plant further comprises a first storage container configured to store solid state particles produced by the reduction reaction and a heat exchanger configured to combine the solid state particles and gas through an oxidation reaction. The heat exchanger is configured to transfer heat produced in the oxidation reaction to a working fluid to heat the working fluid. The CSP plant further comprises a power turbine coupled to the heat exchanger, such that the heated working fluid turns the power turbine, and a generator coupled to and driven by the power turbine to generate electricity.

  13. Thermodynamic investigation of waste cooking oil based hydrogen generation system with chemical looping process

    Directory of Open Access Journals (Sweden)

    Nahla Faleh

    2016-07-01

    The results show that coke formation can be thermodynamically inhibited by increasing the S/C ratio and/or the NiO/C ratio. The conditions that maximize hydrogen production, minimize methane and carbon monoxide content as well as avoid coke formation at thermoneutral conditions were found to be S/C = 5, T = 600 °C and NiO/C = 0.493. Under these conditions, a hydrogen yield of 144.3 mol/kg of soybean waste cooking oil can be obtained, which appears to be an attractive result for starting experimental research.

  14. Device to lower NOx in a gas turbine engine combustion system

    Science.gov (United States)

    Laster, Walter R; Schilp, Reinhard; Wiebe, David J

    2015-02-24

    An emissions control system for a gas turbine engine including a flow-directing structure (24) that delivers combustion gases (22) from a burner (32) to a turbine. The emissions control system includes: a conduit (48) configured to establish fluid communication between compressed air (22) and the combustion gases within the flow-directing structure (24). The compressed air (22) is disposed at a location upstream of a combustor head-end and exhibits an intermediate static pressure less than a static pressure of the combustion gases within the combustor (14). During operation of the gas turbine engine a pressure difference between the intermediate static pressure and a static pressure of the combustion gases within the flow-directing structure (24) is effective to generate a fluid flow through the conduit (48).

  15. Combustion flame-plasma hybrid reactor systems, and chemical reactant sources

    Science.gov (United States)

    Kong, Peter C

    2013-11-26

    Combustion flame-plasma hybrid reactor systems, chemical reactant sources, and related methods are disclosed. In one embodiment, a combustion flame-plasma hybrid reactor system comprising a reaction chamber, a combustion torch positioned to direct a flame into the reaction chamber, and one or more reactant feed assemblies configured to electrically energize at least one electrically conductive solid reactant structure to form a plasma and feed each electrically conductive solid reactant structure into the plasma to form at least one product is disclosed. In an additional embodiment, a chemical reactant source for a combustion flame-plasma hybrid reactor comprising an elongated electrically conductive reactant structure consisting essentially of at least one chemical reactant is disclosed. In further embodiments, methods of forming a chemical reactant source and methods of chemically converting at least one reactant into at least one product are disclosed.

  16. Transformations of inorganic coal constituents in combustion systems

    Energy Technology Data Exchange (ETDEWEB)

    Boni, Arthur A. [PSI Technology Co., Andover, MA (United States); Flagan, Richard C. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Helble, Joseph J. [PSI Technology Co., Andover, MA (United States); Peterson, Thomas W. [Univ. of Arizona, Tucson, AZ (United States); Sarofim, Adel F. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Srinivasachar, Srivats [PSI Technology Co., Andover, MA (United States); Wendt, Jost O.L. [Univ. of Arizona, Tucson, AZ (United States)

    1989-08-01

    Important elements of this work include coal characterization using advanced analytical techniques, testing in small-scale reactors and combustors, modeling of fundamental processes by which mineral transformations occur, as well as incorporating an improved understanding of these processes into an engineering model to predict particle size and composition distributions. Research has been divided into 8 tasks: (1) program planning, management, reporting, and peer review; (2) coal selection preparation and characterization; (3) advanced techniques for coal and mineral characterization; (4) fundamental studies of selected ash vaporization, nucleation, condensation, and coagulation phenomena; (5) fundamental studies of mineral matter vaporization and residual ash formation; (6) pulverized coal combustion studies of ash enrichment by volatiles and fragmentation; (7) idealized combustion determination of ash particle formation and surface stickiness; and (8) model development and integration. This report describes tasks 4-7.

  17. Transformations of inorganic coal constituents in combustion systems

    Energy Technology Data Exchange (ETDEWEB)

    Helble, J.J. (ed.); Srinivasachar, S.; Wilemski, G.; Boni, A.A. (PSI Technology Co., Andover, MA (United States)); Kang, Shin-Gyoo; Sarofim, A.F.; Graham, K.A.; Beer, J.M. (Massachusetts Inst. of Tech., Cambridge, MA (United States)); Peterson, T.W.; Wendt, J.O.L.; Gallagher, N.B.; Bool, L. (Arizona Univ., Tucson, AZ (United States)); Huggins, F.E.; Huffman, G.P.; Shah, N.; Shah, A. (Kentucky Univ., Lexingt

    1992-11-01

    The inorganic constituents or ash contained in pulverized coal significantly increase the environmental and economic costs of coal utilization. For example, ash particles produced during combustion may deposit on heat transfer surfaces, decreasing heat transfer rates and increasing maintenance costs. The minimization of particulate emissions often requires the installation of cleanup devices such as electrostatic precipitators, also adding to the expense of coal utilization. Despite these costly problems, a comprehensive assessment of the ash formation and had never been attempted. At the start of this program, it was hypothesized that ash deposition and ash particle emissions both depended upon the size and chemical composition of individual ash particles. Questions such as: What determines the size of individual ash particles What determines their composition Whether or not particles deposit How combustion conditions, including reactor size, affect these processes remained to be answered. In this 6-year multidisciplinary study, these issues were addressed in detail. The ambitious overall goal was the development of a comprehensive model to predict the size and chemical composition distributions of ash produced during pulverized coal combustion. Results are described.

  18. Ultrafast Structural Dynamics in Combustion Relevant Model Systems

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Peter M. [Brown University

    2014-03-31

    molecular species in the hot environments of combustion processes, there are several features that make the Rydberg ionization spectroscopy uniquely useful. First, the Rydberg electron’s orbit is quite large and covers the entire molecule for most molecular structures of combustion interest. Secondly, the ionization does not change vibrational quantum numbers, so that even complicated and large molecules can be observed with fairly well resolved spectra. In fact, the spectroscopy is blind to vibrational excitation of the molecule. This has the interesting consequence for the study of chemical dynamics, where the molecules are invariably very energetic, that the molecular structures are observed unobstructed by the vibrational congestion that dominates other spectroscopies. This implies also that, as a tool to probe the time-dependent structural dynamics of chemically interesting molecules, Rydberg spectroscopy may well be better suited than electron or x-ray diffraction. With recent progress in calculating Rydberg binding energy spectra, we are approaching the point where the method can be evolved into a structure determination method. To implement the Rydberg ionization spectroscopy we use a molecular beam based, time-resolved pump-probe multi-photon ionization/photoelectron scheme in which a first laser pulse excites the molecule to a Rydberg state, and a probe pulse ionizes the molecule. A time-of-flight detector measures the kinetic energy spectrum of the photoelectrons. The photoelectron spectrum directly provides the binding energy of the electron, and thereby reveals the molecule’s time-dependent structural fingerprint. Only the duration of the laser pulses limits the time resolution. With a new laser system, we have now reached time resolutions better than 100 fs, although very deep UV wavelengths (down to 190 nm) have slightly longer instrument functions. The structural dynamics of molecules in Rydberg-excited states is obtained by delaying the probe ionization

  19. Assessment of external combustion, Brayton-cycle engine potential in total and integrated energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Marciniak, T.J.; Bratis, J.C.; Davis, A.; Jain, M.L.; Ashe, T.L.; Six, L.D.; Trimble, S.W.

    1980-03-01

    The history, advantages, disadvantages, and performance and cost characteristics of the external-combustion, Brayton engine are discussed. Included are studies of external combustion, Brayton engines in Integrated Energy Systems, and comparisons with current technologies, such as diesels and gas turbines, as well as with other advanced prime-mover technologies, such as large Stirling engines and adiabatic turbocompound diesel engines. Lastly, a development program, one that would lead to a commercializable external combustion, Brayton engine using an atmospheric fluidized bed combustor is described. The fluidized bed offers a method for burning coal in an environmentally acceptable manner at a fairly reasonable cost so that the external combustion Brayton concept can be used in the residential/commercial sector. Based on this study, it appears that the external combustion, Brayton engine, using a fluidized-bed combustion system, offers a technologically sound alternative for developing an economically viable, environmentally acceptable method for using non-scarce fuels. Although the efficiency of the engine is not as high as that projected for large diesel and Stirling engines, the capital cost advantages, fuel flexibility, relatively low developmental costs, and high chance of success make it an attractive alternative.

  20. Control and optimization system

    Science.gov (United States)

    Xinsheng, Lou

    2013-02-12

    A system for optimizing a power plant includes a chemical loop having an input for receiving an input parameter (270) and an output for outputting an output parameter (280), a control system operably connected to the chemical loop and having a multiple controller part (230) comprising a model-free controller. The control system receives the output parameter (280), optimizes the input parameter (270) based on the received output parameter (280), and outputs an optimized input parameter (270) to the input of the chemical loop to control a process of the chemical loop in an optimized manner.

  1. 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.

  2. FIELD DEMONSTRATION OF THE LINDE OXYGEN COMBUSTION SYSTEM ON THE EPA MOBILE INCINERATOR

    Science.gov (United States)

    This paper summarizes the various system performance tests and the long-term operating experience of the LINDE Oxygen Combustion System installed on the U.S. Environmental Protection Agency's Mobile Incineration System (MIS) when it was in operation at the Denney Farm site in sou...

  3. Transformations of inorganic coal constituents in combustion systems

    Energy Technology Data Exchange (ETDEWEB)

    Helble, J.J. (ed.); Srinivasachar, S.; Wilemski, G.; Boni, A.A. (PSI Technology Co., Andover, MA (United States)); Kang, Shim-Gyoo; Sarofim, A.F.; Graham, K.A.; Beer, J.M. (Massachusetts Inst. of Tech., Cambridge, MA (United States)); Peterson, T.W.; Wendt, O.L.; Gallagher, N.B.; Bool, L. (Arizona Univ., Tucson, AZ (United States)); Huggins, F.E.; Huffman, G.P.; Shah, N.; Shah, A. (Kentucky Univ., Lexington

    1992-11-01

    This report contains the computer codes developed for the coal combustion project. In Subsection B.1 the FORTRAN code developed for the percolative fragmentation model (or the discrete model, since a char is expressed as a collection of discrete elements in a discrete space) is presented. In Subsection B.2 the code for the continuum model (thus named because mineral inclusions are distributed in a continuum space) is presented. A stereological model code developed to obtain the pore size distribution from a two-dimensional data is presented in Subsection B.3.

  4. Fuel metering system for an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Rado, W.G.

    1983-02-15

    This specification discloses a method for controlling the air fuel ratio for an internal combustion engine having an air supply passage by prepositioning an auxiliary air supply passage to counteract a predicted transient. A stored look-up table indicates the amount of change in the auxiliary air supply passage upon detection of a transient. After the detected transient, the air flow in the auxiliary air supply is adjusted to a value so as to be able to provide a rapid change in magnitude to compensate the next predicted transient. The look-up table is adaptively updated to take into account engine operating conditions.

  5. Gasdynamic modeling and parametric study of mesoscale internal combustion swing engine/generator systems

    Science.gov (United States)

    Gu, Yongxian

    The demand of portable power generation systems for both domestic and military applications has driven the advances of mesoscale internal combustion engine systems. This dissertation was devoted to the gasdynamic modeling and parametric study of the mesoscale internal combustion swing engine/generator systems. First, the system-level thermodynamic modeling for the swing engine/generator systems has been developed. The system performance as well as the potentials of both two- and four-stroke swing engine systems has been investigated based on this model. Then through parameterc studies, the parameters that have significant impacts on the system performance have been identified, among which, the burn time and spark advance time are the critical factors related to combustion process. It is found that the shorter burn time leads to higher system efficiency and power output and the optimal spark advance time is about half of the burn time. Secondly, the turbulent combustion modeling based on levelset method (G-equation) has been implemented into the commercial software FLUENT. Thereafter, the turbulent flame propagation in a generic mesoscale combustion chamber and realistic swing engine chambers has been studied. It is found that, in mesoscale combustion engines, the burn time is dominated by the mean turbulent kinetic energy in the chamber. It is also shown that in a generic mesoscale combustion chamber, the burn time depends on the longest distance between the initial ignition kernel to its walls and by changing the ignition and injection locations, the burn time can be reduced by a factor of two. Furthermore, the studies of turbulent flame propagation in real swing engine chambers show that the combustion can be enhanced through in-chamber turbulence augmentation and with higher engine frequency, the burn time is shorter, which indicates that the in-chamber turbulence can be induced by the motion of moving components as well as the intake gas jet flow. The burn time

  6. On Developing a Spectroscopic System for Fast Gas Temperature Measurements in Combustion Environments

    DEFF Research Database (Denmark)

    Evseev, Vadim; Clausen, Sønnik

    2009-01-01

    is not high enough to trace fast temperature variations which are of great importance for complete combustion diagnostics. To eliminate the above mentioned shortcoming, a new IR spectroscopic-imaging system has been developed at Risø DTU. The schematic of the system is presented. Results on lab and industrial...

  7. A comparative assessment of alternative combustion turbine inlet air cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Brown, D.R.; Katipamula, S.; Konynenbelt, J.H.

    1996-02-01

    Interest in combustion turbine inlet air cooling (CTAC) has increased during the last few years as electric utilities face increasing demand for peak power. Inlet air cooling increases the generating capacity and decreases the heat rate of a combustion turbine during hot weather when the demand for electricity is generally the greatest. Several CTAC systems have been installed, but the general applicability of the concept and the preference for specific concepts is still being debated. Concurrently, Rocky Research of Boulder City, Nevada has been funded by the U.S. Department of Energy to conduct research on complex compound (ammoniated salt) chiller systems for low-temperature refrigeration applications.

  8. Analysis of Combustion Process in Industrial Gas Engine with Prechamber-Based Ignition System

    Directory of Open Access Journals (Sweden)

    Rafał Ślefarski

    2018-02-01

    Full Text Available Application of a pre-combustion chamber (PCC ignition system is one of the methods to improve combustion stability and reduce toxic compounds emission, especially NOx. Using PCC allows the operation of the engine at lean combustion conditions or the utilization of low calorific gaseous fuels such as syngas or biogas. The paper presents the results of an experimental study of the combustion process in two stroke, large bore, stationary gas engine GMVH 12 equipped with two spark plugs (2-SP and a PCC ignition system. The experimental research has been performed during the normal operation of the engine in an industrial compression station. It was observed that application of PCC provides less cycle-to-cycle combustion variation (more than 10% and nitric oxide and carbon monoxide emissions decreased to 60% and 26% respectively. The total hydrocarbon (THC emission rate is 25% higher for the engine equipped with PCC, which results in roughly two percent engine efficiency decrease. Another important criterion of engine retrofitting was the PCC location in the engine head. The experimental results show that improvement of engine operating parameters was recorded only for a configuration with one port offset by 45° from the axis of the main chamber. The study of the ignition delay angle and equivalence ratio in PCC did not demonstrate explicit influence on engine performance.

  9. LES SOFTWARE FOR THE DESIGN OF LOW EMISSION COMBUSTION SYSTEMS FOR VISION 21 PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Steven Cannon; Virgil Adumitroaie; Keith McDaniel; Clifford Smith

    2002-07-01

    Further development of a combustion Large Eddy Simulation (LES) code for the design of advanced gaseous combustion systems is described in this seventh quarterly report. CFD Research Corporation is developing the LES module within the parallel, unstructured solver included in the commercial CFD-ACE+ software. In this quarter, the Localized Dynamic subgrid Kinetic energy Model (LDKM) was improved and an initial Turbulent Artificial Neural Net (TANN) was developed. Validation and testing of the combustion LES code was performed for the Vanderbilt lean premixed combustor and the Loughborough University combustor port flow experiment. Next quarter, LES software development and testing will continue. Alpha testing of the code will continue to be performed on cases of interest to the industrial consortium. Optimization of the subgrid models will be pursued, particularly with the In Situ Adaptive Tabulation (ISAT) approach. Also next quarter, the demonstration of the TANN approach in CFD-ACE+ will be accomplished.

  10. Internal combustion engine system having a power turbine with a broad efficiency range

    Science.gov (United States)

    Whiting, Todd Mathew; Vuk, Carl Thomas

    2010-04-13

    An engine system incorporating an air breathing, reciprocating internal combustion engine having an inlet for air and an exhaust for products of combustion. A centripetal turbine receives products of the combustion and has a housing in which a turbine wheel is rotatable. The housing has first and second passages leading from the inlet to discrete, approximately 180.degree., portions of the circumference of the turbine wheel. The passages have fixed vanes adjacent the periphery of the turbine wheel and the angle of the vanes in one of the passages is different than those in the other so as to accommodate different power levels providing optimum approach angles between the gases passing the vanes and the blades of the turbine wheel. Flow through the passages is controlled by a flapper valve to direct it to one or the other or both passages depending upon the load factor for the engine.

  11. Membrane Systems Engineering for Post-combustion Carbon Capture

    KAUST Repository

    Alshehri, Ali

    2013-08-05

    This study proposes a strategy for optimal design of hollow fiber membrane networks for post combustion carbon capture from power plant multicomponent flue gas. A mathematical model describing multicomponent gas permeation through a separation membrane was customized into the flowsheet modeling package ASPEN PLUS. An N-stage membrane network superstructure was defined considering all possible flowsheeting configurations. An optimization formulation was then developed and solved using an objective function that minimizes the costs associated with operating and capital expenses. For a case study of flue gas feed flow rate of 298 m3/s with 13% CO2 and under defined economic parameters, the optimization resulted in the synthesis of a membrane network structure consisting of two stages in series. This optimal design was found while also considering feed and permeate pressures as well as recycle ratios between stages. The cost of carbon capture for this optimal membrane network is estimated to be $28 per tonne of CO2 captured, considering a membrane permeance of 1000 GPU and membrane selectivity of 50. Following this approach, a reduction in capture cost to less than $20 per tonne CO2 captured is possible if membranes with permeance of 2000 GPU and selectivity higher than 70 materialize.

  12. Design and experimental investigation of an oxy-fuel combustion system for magnetohydrodynamic power extraction

    Science.gov (United States)

    Hernandez, Manuel Johannes

    A general consensus in the scientific and research community is the need to restrict carbon emissions in energy systems. Therefore, extensive research efforts are underway to develop the next generation of energy systems. In the field of power generation, researchers are actively investigating novel methods to produce electricity in a cleaner, efficient form. Recently, Oxy-Combustion for magnetohydrodynamic power extraction has generated significant interest, since the idea was proposed as a method for clean power generation in coal and natural gas power plants. Oxy-combustion technologies have been proposed to provide high enthalpy, electrically conductive flows for direct conversion of electricity. Direct power extraction via magnetohydrodynamics (MHD) can occur as a consequence of the motion of "seeded" combustion products in the presence of magnetic fields. However, oxy-combustion technologies for MHD power extraction has not been demonstrated in the available literature. Furthermore, there are still fundamental unexplored questions remaining, associated with this technology, for MHD power extraction. In this present study, previous magnetohydrodynamic combustion technologies and technical issues in this field were assessed to develop a new combustion system for electrically conductive flows. The research aims were to fully understand the current-state-of-the-art of open-cycle magnetohydrodynamic technologies and present new future directions and concepts. The design criteria, methodology, and technical specifications of an advanced cooled oxy-combustion technology are presented in this dissertation. The design was based on a combined analytical, empirical, and numerical approach. Analytical one-dimensional (1D) design tools initiated design construction. Design variants were analyzed and vetted against performance criteria through the application of computational fluid dynamics modeling. CFD-generated flow fields permitted insightful visualization of the

  13. PARTITIONING OF THE REFRACTORY METALS, NICKEL AND CHROMIUM, IN COMBUSTION SYSTEMS

    Science.gov (United States)

    The partitioning of nickel (Ni) and Chromium (Cr) in combustion systems was investigated theoretically and experimentally. In comparison to other volatile and semi-volatile metals, both Ni and Cr are usually considered to be refractory (non-volatile). Theoretical predictions ba...

  14. Chemical Looping Pilot Plant Results Using a Nickel-Based Oxygen Carrier; Resultats de l'experimentation sur un pilote operant en boucle chimique avec un materiau transporteur d'oxygene a base de nickel

    Energy Technology Data Exchange (ETDEWEB)

    Proll, T.; Kolbitsch, P.; Bolhar-Nordenkampf, J.; Hofbauer, H. [Vienna University of Technology, Institute of Chemical Engineering, Getreidemarkt 9/166, Vienna 1060 (Austria)

    2011-03-15

    A chemical looping pilot plant was designed, built and operated with a design fuel power of 120 kW (lower heating value, natural gas). The system consists of two Circulating Fluidized Bed (CFB) reactors. Operating results are presented and evaluated for a highly reactive nickel-based oxygen carrier, total system inventory 65 kg. The performance in fuel conversion achieved is in the range of 99.8% (CH{sub 4} conversion) and 92% (CO{sub 2} yield). In chemical looping reforming operation, it can be reported that thermodynamic equilibrium is reached in the fuel reactor and that all oxygen is absorbed in the air reactor as soon as the global stoichiometric air/fuel ratio is below 1 and the air reactor temperature is 900 C or more. Even though pure natural gas (98.6 vol.% CH{sub 4}) without steam addition was fed to the fuel reactor, no carbon formation has been found as long as the global stoichiometric air/fuel ratio was larger than 0.4. Based on the experimental findings and on the general state of the art, it is concluded that niche applications such as industrial steam generation from natural gas or CO{sub 2}-ready coupled production of H{sub 2} and N{sub 2} can be interesting pathways for immediate scale-up of the technology. (authors)

  15. Recovery and Sequestration of CO2 from Stationary Combustion Systems by Photosynthesis of Microalgae

    Energy Technology Data Exchange (ETDEWEB)

    Takashi Nakamura; Miguel Olaizola; Stephen M. Masutani

    2003-11-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 July to 30 September 2003 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work during the previous reporting period, Aquasearch and PSI continued preparation work on direct feeding of coal combustion gas to microalgae. Aquasearch started the first full scale carbon sequestration tests with propane combustion gases. Aquasearch started to model the costs associated with biomass harvest from different microalgal strains. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.

  16. Combustion development with a common rail injection system; Verbrennungsentwicklung mit einem Common-Rail-Einspritzsystem

    Energy Technology Data Exchange (ETDEWEB)

    Velji, A. [Verbrennungsentwicklung, MTU, Friedrichshafen (Germany); Danckert, B. [Vorentwicklung, MTU, Friedrichshafen (Germany)

    1997-10-01

    The innovative common rail injection system introduced with the new MTU Series 4000 engines surmounts the typical restriction inherent to conventional injection systems, i.e. the dependency of the injection pressure on engine speed. This paper describes a new combustion development procedure which systematically utilises the advantages of the common rail injection system. As a result of the high injection pressures, which can be reproduced over the complete performance map range, the mixture formation energy can be supplied by the injection system instead of by the air system. This reduces the swirl requirement and allows an increase in the number of injector nozzle holes as well as the employment of a shallow recess in the piston crown. The air can thus be better accomodated in the combustion chamber which, in the end, leads to reduced emissions and fuel consumption. (orig.)

  17. Fuzzy logic control and optimization system

    Science.gov (United States)

    Lou, Xinsheng [West Hartford, CT

    2012-04-17

    A control system (300) for optimizing a power plant includes a chemical loop having an input for receiving an input signal (369) and an output for outputting an output signal (367), and a hierarchical fuzzy control system (400) operably connected to the chemical loop. The hierarchical fuzzy control system (400) includes a plurality of fuzzy controllers (330). The hierarchical fuzzy control system (400) receives the output signal (367), optimizes the input signal (369) based on the received output signal (367), and outputs an optimized input signal (369) to the input of the chemical loop to control a process of the chemical loop in an optimized manner.

  18. AUTOMATIC CONTROL SYSTEM FOR REGULATED HIGH TEMPERATURE MAIN COMBUSTION CHAMBER OF MANEUVERABLE AIRCRAFT MULTIMODE GAS TURBINE ENGINE

    Directory of Open Access Journals (Sweden)

    T. V. Gras’Ko

    2014-01-01

    Full Text Available The paper describes choosing and substantiating the control laws, forming the appearance the automatic control system for regulated high temperature main combustion chamber of maneuverable aircraft multimode gas turbine engine aimed at sustainable and effective functioning of main combustion chamber within a broad operation range.

  19. National Combustion Code, a Multidisciplinary Combustor Design System, Will Be Transferred to the Commercial Sector

    Science.gov (United States)

    Steele, Gynelle C.

    1999-01-01

    The NASA Lewis Research Center and Flow Parametrics will enter into an agreement to commercialize the National Combustion Code (NCC). This multidisciplinary combustor design system utilizes computer-aided design (CAD) tools for geometry creation, advanced mesh generators for creating solid model representations, a common framework for fluid flow and structural analyses, modern postprocessing tools, and parallel processing. This integrated system can facilitate and enhance various phases of the design and analysis process.

  20. Systems of ignition and combustion stabilization for water-coal fuel

    Directory of Open Access Journals (Sweden)

    Zasypkin Ivan M.

    2012-01-01

    Full Text Available The paper presents the review of researches of the ignition and combustion stabilization of the water-coal fuel. Working models of plants are described, the results of their tests in laboratory and industrial conditions are given. Two schemes of the WCF ignition are presented - one with burners with hydrocarbon (solar fuel, and the other with the system of plasma ignition. Advantages of these two systems are described. The promising future of the SPI application in industrial conditions is demonstrated.

  1. LES SOFTWARE FOR THE DESIGN OF LOW EMISSION COMBUSTION SYSTEMS FOR VISION 21 PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Clifford E. Smith; Steven M. Cannon; Virgil Adumitroaie; David L. Black; Karl V. Meredith

    2005-01-01

    In this project, an advanced computational software tool was developed for the design of low emission combustion systems required for Vision 21 clean energy plants. Vision 21 combustion systems, such as combustors for gas turbines, combustors for indirect fired cycles, furnaces and sequestrian-ready combustion systems, will require innovative low emission designs and low development costs if Vision 21 goals are to be realized. The simulation tool will greatly reduce the number of experimental tests; this is especially desirable for gas turbine combustor design since the cost of the high pressure testing is extremely costly. In addition, the software will stimulate new ideas, will provide the capability of assessing and adapting low-emission combustors to alternate fuels, and will greatly reduce the development time cycle of combustion systems. The revolutionary combustion simulation software is able to accurately simulate the highly transient nature of gaseous-fueled (e.g. natural gas, low BTU syngas, hydrogen, biogas etc.) turbulent combustion and assess innovative concepts needed for Vision 21 plants. In addition, the software is capable of analyzing liquid-fueled combustion systems since that capability was developed under a concurrent Air Force Small Business Innovative Research (SBIR) program. The complex physics of the reacting flow field are captured using 3D Large Eddy Simulation (LES) methods, in which large scale transient motion is resolved by time-accurate numerics, while the small scale motion is modeled using advanced subgrid turbulence and chemistry closures. In this way, LES combustion simulations can model many physical aspects that, until now, were impossible to predict with 3D steady-state Reynolds Averaged Navier-Stokes (RANS) analysis, i.e. very low NOx emissions, combustion instability (coupling of unsteady heat and acoustics), lean blowout, flashback, autoignition, etc. LES methods are becoming more and more practical by linking together tens

  2. Biodiesel Performance within Internal Combustion Engine Fuel System - A Review

    Directory of Open Access Journals (Sweden)

    Z.A. Khan

    2016-06-01

    Full Text Available This review paper highlights the tribological performance of biodiesel at contacting surfaces in the fuel delivery system of compression ignition (diesel engines. The focus is on the injection components that include low and high pressure injection pumps, diesel fuel injectors, electro-hydraulic valves, diesel fuel lubricity measurements and effects of biodiesel on the running conditions in a diesel fuel injection system. The common rail system and the distributor pump injection systems with electronic diesel control are among the modern trends that are specifically highlighted. Boundary, mixed and hydrodynamic lubrication regimes together with lubricant oil film thickness, pressure and engine performance are also considered.

  3. Modelling and simulation of wood chip combustion in a hot air generator system.

    Science.gov (United States)

    Rajika, J K A T; Narayana, Mahinsasa

    2016-01-01

    This study focuses on modelling and simulation of horizontal moving bed/grate wood chip combustor. A standalone finite volume based 2-D steady state Euler-Euler Computational Fluid Dynamics (CFD) model was developed for packed bed combustion. Packed bed combustion of a medium scale biomass combustor, which was retrofitted from wood log to wood chip feeding for Tea drying in Sri Lanka, was evaluated by a CFD simulation study. The model was validated by the experimental results of an industrial biomass combustor for a hot air generation system in tea industry. Open-source CFD tool; OpenFOAM was used to generate CFD model source code for the packed bed combustion and simulated along with an available solver for free board region modelling in the CFD tool. Height of the packed bed is about 20 cm and biomass particles are assumed to be spherical shape with constant surface area to volume ratio. Temperature measurements of the combustor are well agreed with simulation results while gas phase compositions have discrepancies. Combustion efficiency of the validated hot air generator is around 52.2 %.

  4. Development of eddy current testing system for inspection of combustion chambers of liquid rocket engines.

    Science.gov (United States)

    He, D F; Zhang, Y Z; Shiwa, M; Moriya, S

    2013-01-01

    An eddy current testing (ECT) system using a high sensitive anisotropic magnetoresistive (AMR) sensor was developed. In this system, a 20 turn circular coil with a diameter of 3 mm was used to produce the excitation field. A high sensitivity AMR sensor was used to measure the magnetic field produced by the induced eddy currents. A specimen made of copper alloy was prepared to simulate the combustion chamber of liquid rocket. Scanning was realized by rotating the chamber with a motor. To reduce the influence of liftoff variance during scanning, a dual frequency excitation method was used. The experimental results proved that ECT system with an AMR sensor could be used to check liquid rocket combustion chamber.

  5. Adaptive system of supplying lubricant to the internal combustion engine

    Science.gov (United States)

    Barylnikova, E. P.; Kulakov, A. T.; Kulakov, O. A.

    2017-09-01

    This paper assesses the impact of reducing the pressure in the lubrication system on the failures of the crankshaft bearings. The method of adapting lubricating system of the diesel engine as the wear in operation and depending on the operation modes.

  6. Biomass Power Generation through Direct Integration of Updraft Gasifier and Stirling Engine Combustion System

    Directory of Open Access Journals (Sweden)

    Jai-Houng Leu

    2010-01-01

    Full Text Available Biomass is the largest renewable energy source in the world. Its importance grows gradually in the future energy market. Since most biomass sources are low in energy density and are widespread in space, small-scale biomass conversion system is therefore more competitive than a large stand-alone conversion plant. The current study proposes a small-scale solid biomass power system to explore the viability of direct coupling of an updraft fixed bed gasifier with a Stirling engine. The modified updraft fixed bed gasifier employs an embedded combustor inside the gasifier to fully combust the synthetic gas generated by the gasifier. The flue gas produced by the synthetic gas combustion inside the combustion tube is piped directly to the heater head of the Stirling engine. The engine will then extract and convert the heat contained in the flue gas into electricity automatically. Output depends on heat input. And, the heat input is proportional to the flow rate and temperature of the flue gas. The preliminary study of the proposed direct coupling of an updraft gasifier with a 25 kW Stirling engine demonstrates that full power output could be produced by the current system. It could be found from the current investigation that no auxiliary fuel is required to operate the current system smoothly. The proposed technology and units could be considered as a viable solid biomass power system.

  7. Modelling the effects of heat loss and fuel/air mixing on turbulent combustion in gas turbine combustion systems

    NARCIS (Netherlands)

    Gövert, S.

    2016-01-01

    The present study is concerned with the development and validation of a simulation framework for the accurate prediction of turbulent reacting flows at reduced computational costs. Therefore, a combustion model based on the tabulation of laminar premixed flamelets is employed. By compilation of

  8. Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Venkatesan, Krishna

    2011-11-30

    The purpose of this program was to develop low-emissions, efficient fuel-flexible combustion technology which enables operation of a given gas turbine on a wider range of opportunity fuels that lie outside of current natural gas-centered fuel specifications. The program encompasses a selection of important, representative fuels of opportunity for gas turbines with widely varying fundamental properties of combustion. The research program covers conceptual and detailed combustor design, fabrication, and testing of retrofitable and/or novel fuel-flexible gas turbine combustor hardware, specifically advanced fuel nozzle technology, at full-scale gas turbine combustor conditions. This project was performed over the period of October 2008 through September 2011 under Cooperative Agreement DE-FC26-08NT05868 for the U.S. Department of Energy/National Energy Technology Laboratory (USDOE/NETL) entitled "Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines". The overall objective of this program was met with great success. GE was able to successfully demonstrate the operability of two fuel-flexible combustion nozzles over a wide range of opportunity fuels at heavy-duty gas turbine conditions while meeting emissions goals. The GE MS6000B ("6B") gas turbine engine was chosen as the target platform for new fuel-flexible premixer development. Comprehensive conceptual design and analysis of new fuel-flexible premixing nozzles were undertaken. Gas turbine cycle models and detailed flow network models of the combustor provide the premixer conditions (temperature, pressure, pressure drops, velocities, and air flow splits) and illustrate the impact of widely varying fuel flow rates on the combustor. Detailed chemical kinetic mechanisms were employed to compare some fundamental combustion characteristics of the target fuels, including flame speeds and lean blow-out behavior. Perfectly premixed combustion experiments were conducted to

  9. Dynamic graph of an oxy-fuel combustion system using autocatalytic set model

    Science.gov (United States)

    Harish, Noor Ainy; Bakar, Sumarni Abu

    2017-08-01

    Evaporation process is one of the main processes besides combustion process in an oxy-combustion boiler system. An Autocatalytic Set (ASC) Model has successfully applied in developing graphical representation of the chemical reactions that occurs in the evaporation process in the system. Seventeen variables identified in the process are represented as nodes and the catalytic relationships are represented as edges in the graph. In addition, in this paper graph dynamics of ACS is further investigated. By using Dynamic Autocatalytic Set Graph Algorithm (DAGA), the adjacency matrix for each of the graphs and its relations to Perron-Frobenius Theorem is investigated. The dynamic graph obtained is further investigated where the connection of the graph to fuzzy graph Type 1 is established.

  10. The combustion system of the MAN 20V35/44G gas engine

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Markus; Auer, Matthias; Stiesch, Gunnnar [MAN Diesel and Turbo SE, Augsburg (Germany)

    2013-05-15

    The new gas engine 20V35/44G by MAN Diesel and Turbo SE has a power output of 10.6 MW. The high effective efficiency level of 48.4 % as well as numerous technical innovations allow an environmentally-friendly, economical and reliable engine operation. Key to achieve this is the combustion system, which has been optimised during advanced engineering by means of modern simulation tools and extensive single-cylinder tests. (orig.)

  11. Transport Phenomena and Interfacial Kinetics in Multiphase Combustion Systems

    Science.gov (United States)

    1991-02-01

    Transport phenomena involving the motion of small (mass-)loaded aerosol systems, the literature of this particles suspended in gaseous media and theit depo...flowing nonisothermal gaseous would expect S k to have a similar influence on the media , simultaneously including for the first time the convective...is in the tihermal BL and its infuence on the total much larger than the characteristic time re- deposition rate is taken into account. Since the im

  12. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Takashi Nakamura

    2003-09-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 April to 30 June 2003 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work during the previous reporting period, PSI delivered its coal reactor to Aquasearch. Aquasearch and PSI continued preparation work on direct feeding of coal combustion gas to microalgae. Aquasearch started their effort on economic analyses of commercial scale photobioreactor. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.

  13. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. T. Nakamura; Dr. Miguel Olaizola; Dr. Stephen M. Masutani

    2002-10-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 April to 30 June 2002 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on feasibility demonstration of direct feeding of coal combustion gas to microalgae. Aquasearch continued their effort on selection and characterization of microalgae suitable for CO{sub 2} sequestration. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.

  14. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. T. Nakamura

    2003-05-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 January to 31 March 2003 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work during the previous reporting period, PSI conducted preparation work on direct feeding of coal combustion gas to microalgae and developed a design concept for photobioreactors for biofixation of CO{sub 2} and photovoltaic power generation. Aquasearch continued their effort on characterization of microalgae suitable for CO{sub 2} sequestration and preparation for pilot scale demonstration. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.

  15. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. T. Nakamura; Dr. Miguel Olaizola; Dr. Stephen M. Masutani

    2002-12-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 July to 30 September 2002 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on feasibility demonstration of direct feeding of coal combustion gas to microalgae. Aquasearch continued their effort on selection and characterization of microalgae suitable for CO{sub 2} sequestration. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.

  16. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Takashi Nakamura

    2003-04-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 October to 31 December 2002 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on feasibility demonstration of direct feeding of coal combustion gas to microalgae. Aquasearch continued their effort on selection and characterization of microalgae suitable for CO{sub 2} sequestration. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.

  17. Factors affecting the corrosion rates of ceramics in coal combustion systems

    Energy Technology Data Exchange (ETDEWEB)

    Hurley, J.P. [Univ. of North Dakota, Grand Forks, ND (United States)

    1995-08-01

    The concentrations of approximately a dozen elements in the products of coal combustion affect the corrosion rates of ceramics used to construct the combustion system. The elements, including H, O, Na, Mg, Al, Si, P, S, Cl, K, Ca, and Fe, affect corrosion rates in three ways: as primary corrodants of the materials, as secondary corrodants that affect the activities of the primary corrodants, and by affecting the mass transport rate of the primary corrodants. A full factorial study of corrosion rates performed by varying the concentrations of these elements would involve X{sup n} tests, where X is the number of variations of each element and n is the number of different elements. For three variations (low, medium, and high concentrations) of each of 12 elements, the number of tests is 531,441 for a single temperature and pressure condition. The numbers can be reduced with the use of a fractional factorial test matrix, but the most effective way to perform corrosion tests is to base them on realistic system conditions. In this paper, the effects of the composition and physical state of the products of coal combustion on ceramic corrosion rates are given along with suggestions of appropriate test conditions for specific system components.

  18. Multifunctional Pd/Ni-Co catalyst for hydrogen production by chemical looping coupled with steam reforming of acetic acid.

    Science.gov (United States)

    Fermoso, Javier; Gil, María V; Rubiera, Fernando; Chen, De

    2014-11-01

    High yield of high-purity H2 from acetic acid, a model compound of bio-oil obtained from the fast pyrolysis of biomass, was produced by sorption-enhanced steam reforming (SESR). An oxygen carrier was introduced into a chemical loop (CL) coupled to the cyclical SESR process to supply heat in situ for the endothermic sorbent regeneration to increase the energy efficiency of the process. A new multifunctional 1 %Pd/20 %Ni-20 %Co catalyst was developed for use both as oxygen carrier in the CL and as reforming catalyst in the SESR whereas a CaO-based material was used as CO2 sorbent. In the sorbent-air regeneration step, the Ni-Co atoms in the catalyst undergo strong exothermic oxidation reactions that provide heat for the CaO decarbonation. The addition of Pd to the Ni-Co catalyst makes the catalyst active throughout the whole SESR-CL cycle. Pd significantly promotes the reduction of Ni-Co oxides to metallic Ni-Co during the reforming stage, which avoids the need for a reduction step after regeneration. H2 yield above 90 % and H2 purity above 99.2 vol % were obtained. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Hydrogen Production from Cyclic Chemical Looping Steam Methane Reforming over Yttrium Promoted Ni/SBA-16 Oxygen Carrier

    Directory of Open Access Journals (Sweden)

    Sanaz Daneshmand-Jahromi

    2017-09-01

    Full Text Available In this work, the modification of Ni/SBA-16 oxygen carrier (OC with yttrium promoter is investigated. The yttrium promoted Ni-based oxygen carrier was synthesized via co-impregnation method and applied in chemical looping steam methane reforming (CL-SMR process, which is used for the production of clean energy carrier. The reaction temperature (500–750 °C, Y loading (2.5–7.4 wt. %, steam/carbon molar ratio (1–5, Ni loading (10–30 wt. % and life time of OCs over 16 cycles at 650 °C were studied to investigate and optimize the structure of OC and process temperature with maximizing average methane conversion and hydrogen production yield. The synthesized OCs were characterized by multiples techniques. The results of X-ray powder diffraction (XRD and energy dispersive X-ray spectroscopy (EDX of reacted OCs showed that the presence of Y particles on the surface of OCs reduces the coke formation. The smaller NiO species were found for the yttrium promoted OC and therefore the distribution of Ni particles was improved. The reduction-oxidation (redox results revealed that 25Ni-2.5Y/SBA-16 OC has the highest catalytic activity of about 99.83% average CH4 conversion and 85.34% H2 production yield at reduction temperature of 650 °C with the steam to carbon molar ratio of 2.

  20. High purity H2 by sorption-enhanced chemical looping reforming of waste cooking oil in a packed bed reactor.

    Science.gov (United States)

    Pimenidou, P; Rickett, G; Dupont, V; Twigg, M V

    2010-12-01

    High purity hydrogen (>95%) was produced at 600 degrees C and 1 atm by steam reforming of waste cooking oil at a molar steam to carbon ratio of 4 using chemical looping, a process that features redox cycles of a Ni catalyst with the in-situ carbonation/calcination of a CO(2) sorbent (dolomite) in a packed bed reactor under alternated feedstreams of fuel-steam and air. The fuel and steam conversion were higher with the sorbent present than without it. Initially, the dolomite carbonation was very efficient (100%), and 98% purity hydrogen was produced, but the carbonation decreased to around 56% with a purity of 95% respectively in the following cycles. Reduction of the nickel catalyst occurred alongside steam reforming, water gas shift and carbonation, with H(2) produced continuously under fuel-steam feeds. Catalyst and CO(2)-sorbent regeneration was observed, and long periods of autothermal operation within each cycle were demonstrated. 2010 Elsevier Ltd. All rights reserved.

  1. Toward the Oxidation of the Phenyl Radical and Prevention of PAH Formation in Combustion Systems.

    Science.gov (United States)

    Parker, Dorian S N; Kaiser, Ralf I; Troy, Tyler P; Kostko, Oleg; Ahmed, Musahid; Mebel, Alexander M

    2015-07-16

    The reaction of the phenyl radical (C6H5) with molecular oxygen (O2) plays a central role in the degradation of poly- and monocyclic aromatic radicals in combustion systems which would otherwise react with fuel components to form polycyclic aromatic hydrocarbons (PAHs) and eventually soot. Despite intense theoretical and experimental scrutiny over half a century, the overall reaction channels have not all been experimentally identified. Tunable vacuum ultraviolet photoionization in conjunction with a combustion simulating chemical reactor uniquely provides the complete isomer specific product spectrum and branching ratios of this prototype reaction. In the reaction of phenyl radicals and molecular oxygen at 873 K and 1003 K, ortho-benzoquinone (o-C6H4O2), the phenoxy radical (C6H5O), and cyclopentadienyl radical (C5H5) were identified as primary products formed through emission of atomic hydrogen, atomic oxygen and carbon dioxide. Furan (C4H4O), acrolein (C3H4O), and ketene (C2H2O) were also identified as primary products formed through ring opening and fragmentation of the 7-membered ring 2-oxepinoxy radical. Secondary reaction products para-benzoquinone (p-C6H4O2), phenol (C6H5OH), cyclopentadiene (C5H6), 2,4-cyclopentadienone (C5H4O), vinylacetylene (C4H4), and acetylene (C2H2) were also identified. The pyranyl radical (C5H5O) was not detected; however, electronic structure calculations show that it is formed and isomerizes to 2,4-cyclopentadienone through atomic hydrogen emission. In combustion systems, barrierless phenyl-type radical oxidation reactions could even degrade more complex aromatic radicals. An understanding of these elementary processes is expected to lead to a better understanding toward the elimination of carcinogenic, mutagenic, and environmentally hazardous byproducts of combustion systems such as PAHs.

  2. Risk analysis of highly combustible gas storage, supply, and distribution systems in PWR plants

    Energy Technology Data Exchange (ETDEWEB)

    Simion, G.P. [Science Applications International Corp., Albuquerque, NM (United States); VanHorn, R.L.; Smith, C.L.; Bickel, J.H.; Sattison, M.B. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Bulmahn, K.D. [SCIENTECH, Inc., Idaho Falls, ID (United States)

    1993-06-01

    This report presents the evaluation of the potential safety concerns for pressurized water reactors (PWRs) identified in Generic Safety Issue 106, Piping and the Use of Highly Combustible Gases in Vital Areas. A Westinghouse four-loop PWR plant was analyzed for the risk due to the use of combustible gases (predominantly hydrogen) within the plant. The analysis evaluated an actual hydrogen distribution configuration and conducted several sensitivity studies to determine the potential variability among PWRs. The sensitivity studies were based on hydrogen and safety-related equipment configurations observed at other PWRs within the United States. Several options for improving the hydrogen distribution system design were identified and evaluated for their effect on risk and core damage frequency. A cost/benefit analysis was performed to determine whether alternatives considered were justifiable based on the safety improvement and economics of each possible improvement.

  3. Misfire detection based on switched state observer of hybrid system in internal combustion engine

    Science.gov (United States)

    Zhang, Yu; Zhou, Tonglin; Zheng, Taixiong; Han, Weimin; Tan, Rui; Wang, Yanjun

    2017-04-01

    This paper proposes a novel switched state observer of hybrid system using Luenberger sliding mode observer to estimate crankshaft angular acceleration which is further applied to detect misfire fault. The output error of hybrid system of internal combustion engine (engine speed) and the designed observer (estimated speed) is taken as input of observer to estimate crankshaft acceleration. Convergence of hybrid system is proven through Lyapunov stability theory. The experimental results show that the presented estimated technique has a higher accuracy and can be effectively used to misfire detection compared with reduced-order observer and sliding mode observer.

  4. Fluid-Structure Interaction in Combustion System of a Gas Turbine—Effect of Liner Vibrations

    NARCIS (Netherlands)

    Pozarlik, Artur Krzysztof; Kok, Jacobus B.W.

    2014-01-01

    Prediction of mutual interaction between flow, combustion, acoustic, and vibration phenomena occurring in a combustion chamber is crucial for the reliable operation of any combustion device. In this paper, this is studied with application to the combustion chamber of a gas turbine. Very dangerous

  5. Optimization of the Working Cycle for an Underwater Propulsion System Based on Aluminium-Water Combustion

    Science.gov (United States)

    Chen, Xianhe; Xia, Zhixun; Huang, Liya; Hu, Jianxin

    2017-05-01

    The working cycle of a novel underwater propulsion system based on aluminium combustion with water is researched in order to evaluate the best performance. The system exploits the exothermic reaction between aluminium and water which will produce high temperature, pressure steam and hydrogen mixture that can be used to drive turbine to generate power. Several new system configurations corresponding to different working cycles are investigated, and their performance parameters in terms of net power, energy density and global efficiency are discussed. The results of the system simulation show that using the recirculation steam rather than hydrogen as the carrier gas, the system net power, energy density and efficiency of the system are greatly increased compared, however the system performance is close either using adiabatic compression or isothermal compression. And if an evaporator component is added into system in order to take full use of the solid product heat, the system performance will be improved.

  6. Application of Heterogeneous Catalysis in Small-Scale Biomass Combustion Systems

    Directory of Open Access Journals (Sweden)

    Christian Thiel

    2012-04-01

    Full Text Available Combustion of solid biomass fuels for heat generation is an important renewable energy resource. The major part among biomass combustion applications is being played by small-scale systems like wood log stoves and small wood pellet burners, which account for 75% of the overall biomass heat production. Despite an environmentally friendly use of renewable energies, incomplete combustion in small-scale systems can lead to the emission of environmental pollutants as well as substances which are hazardous to health. Besides particles of ash and soot, a wide variety of gaseous substances can also be emitted. Among those, polycyclic aromatic hydrocarbons (PAH and several organic volatile and semi-volatile compounds (VOC are present. Heterogeneous catalysis is applied for the reduction of various gaseous compounds as well as soot. Some research has been done to examine the application of catalytic converters in small-scale biomass combustion systems. In addition to catalyst selection with respect to complete oxidation of different organic compounds, parameters such as long-term stability and durability under flue gas conditions are considered for use in biomass combustion furnaces. Possible catalytic procedures have been identified for investigation by literature and market research. Experimental studies with two selected oxidation catalysts based on noble metals have been carried out on a wood log stove with a retrofit system. The measurements have been performed under defined conditions based on practical mode of operation. The measurements have shown that the catalytic flue gas treatment is a promising method to reduce carbon monoxide and volatile organic compounds. Even a reduction of particulate matter was observed, although no filtering effect could be detected. Therefore, the oxidation of soot or soot precursors can be assumed. The selected catalysts differed in their activity, depending on the compound to be oxidized. Examinations showed that

  7. Development and testing of commercial-scale, coal-fired combustion systems: Phase III. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    Based on studies that indicated a large potential for significantly increased coal-firing in the commercial sector, the U.S. Department of Energy`s Pittsburgh Energy Technology Center (PETC) sponsored a multi-phase development effort for advanced coal combustion systems. This Final Report presents the results of the last phase (Phase III) of a project for the development of an advanced coal-fired system for the commercial sector of the economy. The project performance goals for the system included dual-fuel capability (i.e., coal as primary fuel and natural gas as secondary fuel), combustion efficiency exceeding 99 percent, thermal efficiency greater than 80 percent, turndown of at least 3:1, dust-free and semi-automatic dry ash removal, fully automatic start-up with system purge and ignition verification, emissions performance exceeding New Source Performance Standards (NSPS) and approaching those produced by oil-fired, Commercial-sized units, and reliability, safety, operability, maintainability, and service life comparable to oil-fired units. The program also involved a site demonstration at a large facility owned by Striegel Supply Company, a portion of which was leased to MTCI. The site, mostly warehouse space, was completely unheated and the advanced coal-fired combustion system was designed and sized to heat this space. Three different coals were used in the project, one low and one high sulfur pulverized Pittsburgh No. 8 coal, and a micronized low volatile, bituminous coal. The sorbents used were Pfizer dolomitic limestone and an Anvil lime. More than 100 hours of screening test`s were performed to characterize the system. The parameters examined included coal firing rate, excess air level, ash recycle rate, coal type, dolomitic limestone feed rate, and steam injection rate. These tests indicated that some additional modifications for coal burning in the system were required.

  8. LES SOFTWARE FOR THE DESIGN OF LOW EMISSION COMBUSTION SYSTEMS FOR VISION 21 PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Steven Cannon; Clifford Smith

    2003-04-01

    Application and testing of the new combustion Large Eddy Simulation (LES) code for the design of advanced gaseous combustion systems is described in this 10th quarterly report. CFD Research Corporation has developed the LES module within the parallel, unstructured solver included in the commercial CFD-ACE+ software. In this quarter, validation and testing of the combustion LES code was performed for the DOE-Simval combustor. Also, Beta testing by consortium members was performed for various burner and combustor configurations. In the two quarters ahead, CFDRC will validate the code on the new DOE SimVal experiments. Experimental data from DOE should be available in June 2003, though LES calculations are currently being performed. This will ensure a truly predictive test of the software. CFDRC will also provide help to the consortium members on running their cases, and incorporate improvements to the software suggested by the beta testers. The beta testers will compare their predictions with experimental measurements and other numerical calculations. At the end of this project (October, 2003), a final released version of the software will be available for licensing to the general public.

  9. Droplet evaporation and combustion in a liquid-gas multiphase system

    Science.gov (United States)

    Muradoglu, Metin; Irfan, Muhammad

    2017-11-01

    Droplet evaporation and combustion in a liquid-gas multiphase system are studied computationally using a front-tracking method. One field formulation is used to solve the flow, energy and species equations with suitable jump conditions. Both phases are assumed to be incompressible; however, the divergence-free velocity field condition is modified to account for the phase change at the interface. Both temperature and species gradient driven phase change processes are simulated. Extensive validation studies are performed using the benchmark cases: The Stefan and the sucking interface problems, d2 law and wet bulb temperature comparison with the psychrometric chart values. The phase change solver is then extended to incorporate the burning process following the evaporation as a first step towards the development of a computational framework for spray combustion. We used detailed chemistry, variable transport properties and ideal gas behaviour for a n-heptane droplet combustion; the chemical kinetics being handled by the CHEMKIN. An operator-splitting approach is used to advance temperature and species mass fraction in time. The numerical results of the droplet burning rate, flame temperature and flame standoff ratio show good agreement with the experimental and previous numeric.

  10. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Takashi Nakamura

    2004-11-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 April to 30 June 2004 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work during the previous reporting period, Aquasearch run further, pilot and full scale, carbon sequestration tests with actual propane combustion gases utilizing two different strains of microalgae. Aquasearch continued testing modifications to the coal combustor to allow for longer-term burns. Aquasearch also tested an alternative cell separation technology. University of Hawaii performed experiments at the Mera Pharmaceuticals facility in Kona in mid June to obtain data on the carbon venting rate out of the photobioreactor; gas venting rates were measured with an orifice flow meter and gas samples were collected for GC analysis to determine the carbon content of the vented gases.

  11. Design and Operation of the Synthesis Gas Generator System for Reformed Propane and Glycerin Combustion

    Science.gov (United States)

    Pickett, Derek Kyle

    Due to an increased interest in sustainable energy, biodiesel has become much more widely used in the last several years. Glycerin, one major waste component in biodiesel production, can be converted into a hydrogen rich synthesis gas to be used in an engine generator to recover energy from the biodiesel production process. This thesis contains information detailing the production, testing, and analysis of a unique synthesis generator rig at the University of Kansas. Chapter 2 gives a complete background of all major components, as well as how they are operated. In addition to component descriptions, methods for operating the system on pure propane, reformed propane, reformed glycerin along with the methodology of data acquisition is described. This chapter will serve as a complete operating manual for future students to continue research on the project. Chapter 3 details the literature review that was completed to better understand fuel reforming of propane and glycerin. This chapter also describes the numerical model produced to estimate the species produced during reformation activities. The model was applied to propane reformation in a proof of concept and calibration test before moving to glycerin reformation and its subsequent combustion. Chapter 4 first describes the efforts to apply the numerical model to glycerin using the calibration tools from propane reformation. It then discusses catalytic material preparation and glycerin reformation tests. Gas chromatography analysis of the reformer effluent was completed to compare to theoretical values from the numerical model. Finally, combustion of reformed glycerin was completed for power generation. Tests were completed to compare emissions from syngas combustion and propane combustion.

  12. 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.

  13. Chemical Looping Pilot Plant Results Using a Nickel-Based Oxygen Carrier Résultats de l’expérimentation sur un pilote opérant en boucle chimique avec un matériau transporteur d’oxygène à base de nickel

    Directory of Open Access Journals (Sweden)

    Pröll T.

    2011-04-01

    Full Text Available A chemical looping pilot plant was designed, built and operated with a design fuel power of 120 kW (lower heating value, natural gas. The system consists of two Circulating Fluidized Bed (CFB reactors. Operating results are presented and evaluated for a highly reactive nickel-based oxygen carrier, total system inventory 65 kg. The performance in fuel conversion achieved is in the range of 99.8% (CH4 conversion and 92% (CO2 yield. In chemical looping reforming operation, it can be reported that thermodynamic equilibrium is reached in the fuel reactor and that all oxygen is absorbed in the air reactor as soon as the global stoichiometric air/fuel ratio is below 1 and the air reactor temperature is 900°C or more. Even though pure natural gas (98.6 vol.% CH4 without steam addition was fed to the fuel reactor, no carbon formation has been found as long as the global stoichiometric air/fuel ratio was larger than 0.4. Based on the experimental findings and on the general state of the art, it is concluded that niche applications such as industrial steam generation from natural gas or CO2-ready coupled production of H2 and N2 can be interesting pathways for immediate scale-up of the technology. Un pilote d’étude de la combustion en boucle chimique d’une puissance thermique de 120 kW a été dimensionné, construit et opéré. Il est constitué de deux lits circulants interconnectés. Les résultats d’opération qui sont présentés ont été obtenus avec un matériau transporteur d’oxygène très réactif à base de nickel. L’inventaire total du matériau est de 65 kg dans le pilote. La conversion du méthane atteinte est voisine de 99,8 % et le rendement en CO2 est de 92 %. Lorsqu’on opère en mode de reformage, l’équilibre thermodynamique est atteint dans le réacteur fioul. Tout l’oxygène est capté dans le réacteur air dès que le rapport stoechiométrique entre l’air et le méthane est inférieur à 1 et que la temp

  14. Research Data Supporting "Synthesis, Application and Carbonation Behaviour of Ca2Fe2O5 for Chemical Looping H2 Production"

    OpenAIRE

    Ismail, Mohammad; Liu, Wen; Chan, Martin S.C.; Dunstan, Matthew T.; Scott, Stuart A

    2016-01-01

    Chemical looping hydrogen production uses the oxidation and reduction of metal oxides, typically iron, to produce hydrogen. This work focuses on the modification of iron oxide with calcium oxide to form an oxygen carrier containing di-calcium ferrite (Ca2Fe2O5), which presents favourable thermodynamics for achieving higher conversions of steam to hydrogen compared to chemically unmodified iron oxide. Different methods of synthesis, viz. mechanochemical synthesis and co-precipitation, were use...

  15. Automotive Thermoelectric Generator impact on the efficiency of a drive system with a combustion engine

    Directory of Open Access Journals (Sweden)

    Ziolkowski Andrzej

    2017-01-01

    Full Text Available Increasing the combustion engine drive systems efficiency is currently being achieved by structural changes in internal combustion engines and its equipment, which are geared towards limiting mechanical, thermal and outlet losses. For this reason, downsizing. In addition to these changes, all manner of exhaust gas energy recovery systems are being investigated and implemented, including turbocompound, turbogenerators and thermoelectric generators. The article presents the author’s idea of a thermoelectric generator system of automotive applications ATEG (Automotive Thermoelectric Generator and the study of the recovery of exhaust gas energy stream. The ATEG consists of a heat exchanger, thermoelectric modules and a cooling system. In this solution, 24 commercial thermoelectric modules based on Bi2Te3 (bismuth telluride were used. Measurements were made at two engine test sites on which SI and CI engines were installed. The exhaust gas parameters (temperature and mass flow rate, fuel consumption and operating parameters of the ATEG – the intensity and the voltage generated by the thermoelectric modules and the temperature on the walls of the heat exchanger – were all measured in the experiments. Based on the obtained results, the exhaust gas energy flow and the power of the ATEG were determined as well as its effect on the diesel engine drive system efficiency.

  16. Atmospheric emission characterization of a novel sludge drying and co-combustion system.

    Science.gov (United States)

    Lu, Shengyong; Yang, Liqin; Zhou, Fa; Wang, Fei; Yan, Jianhua; Li, Xiaodong; Chi, Yong; Cen, Kefa

    2013-10-01

    A novel system combining sludge drying and co-combustion with coal was applied in disposing sludge and its atmospheric emission characteristics were tested. The system was composed of a hollow blade paddle dryer, a thermal drying exhaust gas control system, a 75 tons/hr circulating fluidized bed and a flue gas cleaning system. The emissions of NH3, SO2, CH4 and some other pollutants released from thermal drying, and pollutants such as NOx, SO2 etc. discharged by the incinerator, were all tested. Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in the flue gas from the incinerator were investigated as well. The results indicated that the concentrations of NOx and SO2 in the flue gas from the incinerator were 145 and 16 mg/m3, respectively. and the I-TEQ concentration of 2,3,7,8-substitued PCDD/Fs was 0.023 ng I-TEQ/Nm3. All these values were greatly lower than the emission standards of China. In addition, there was no obvious odor in the air around the sludge dryer. The results demonstrated that this drying and co-combustion system is efficient in controlling pollutants and is a feasible way for large-scale treatment of industrial sludge and sewage sludge.

  17. Development of Computational Capabilities to Predict the Corrosion Wastage of Boiler Tubes in Advanced Combustion Systems

    Energy Technology Data Exchange (ETDEWEB)

    Kung, Steven; Rapp, Robert

    2014-08-31

    A comprehensive corrosion research project consisting of pilot-scale combustion testing and long-term laboratory corrosion study has been successfully performed. A pilot-scale combustion facility available at Brigham Young University was selected and modified to enable burning of pulverized coals under the operating conditions typical for advanced coal-fired utility boilers. Eight United States (U.S.) coals were selected for this investigation, with the test conditions for all coals set to have the same heat input to the combustor. In addition, the air/fuel stoichiometric ratio was controlled so that staged combustion was established, with the stoichiometric ratio maintained at 0.85 in the burner zone and 1.15 in the burnout zone. The burner zone represented the lower furnace of utility boilers, while the burnout zone mimicked the upper furnace areas adjacent to the superheaters and reheaters. From this staged combustion, approximately 3% excess oxygen was attained in the combustion gas at the furnace outlet. During each of the pilot-scale combustion tests, extensive online measurements of the flue gas compositions were performed. In addition, deposit samples were collected at the same location for chemical analyses. Such extensive gas and deposit analyses enabled detailed characterization of the actual combustion environments existing at the lower furnace walls under reducing conditions and those adjacent to the superheaters and reheaters under oxidizing conditions in advanced U.S. coal-fired utility boilers. The gas and deposit compositions were then carefully simulated in a series of 1000-hour laboratory corrosion tests, in which the corrosion performances of different commercial candidate alloys and weld overlays were evaluated at various temperatures for advanced boiler systems. Results of this laboratory study led to significant improvement in understanding of the corrosion mechanisms operating on the furnace walls as well as superheaters and reheaters in

  18. Experimental study of a staged combustion system for stationary gas turbine applications

    Science.gov (United States)

    Lamont, Warren G.

    Two optically accessible experimental test rigs were designed and constructed to investigate a staged or distributed combustion system for stationary gas turbine applications. The test rigs were fuelled with natural gas and featured two combustion zones: the main combustion zone (MCZ) and the secondary combustion zone (SCZ). The MCZ is a swirl stabilized dump combustor and the SCZ, which is axially downstream from the MCZ, is formed by a transverse jet injecting a premixed fuel/air mixture into the vitiated stream. After installing and commissioning the test rig, an emission survey was conducted to investigate the SCZ conditions, equivalence ratio and momentum ratio, that produce low NOx emissions and give a higher temperature rise before a simulated high pressure turbine than firing only the MCZ. The emission survey found several operating conditions that show the benefit of combustion staging. These beneficial conditions had an SCZ equivalence ratio between 0.41 and 1.12. The data from the emission survey was then used to create an artificial neural network (ANN). The ANN used a multi-layer feed-forward network architecture and was trained with experimental data using the backpropagation training algorithm. The ANN was then used to create performance maps and optimum operational regions were sought. Lastly, optical diagnostics were used to obtain information on the nature of the SCZ reactive jet. The diagnostics included high speed CH* chemiluminescence, OH planar laser induced fluorescence (PLIF) and dual-pump coherent anti-Stokes Raman scattering (CARS). The chemiluminescence and PLIF were used to qualitatively determine the size and shape of the transverse jet reaction zone. Dual-pump CARS was used to quantitatively determine the temperature and H2/N2 concentration ratio profile at the mid-plane of the transverse jet. Dual-pump CARS data was collected for four operating conditions but only one is presented in this dissertation. For the condition presented, the

  19. From orbital debris capture systems through internal combustion engines on Mars

    Science.gov (United States)

    1991-01-01

    The investigation and conceptualization of an orbital debris collector was the primary area of design. In addition, an alternate structural design for Space Station Freedom and systems supporting resource utilization at Mars and the moon were studied. Hardware for production of oxygen from simulate Mars atmosphere was modified to permit more reliable operation at low pressures (down to 10 mb). An internal combustion engine was altered to study how Mars atmosphere could be used as a diluent to control combustion temperatures and avoid excess Mars propellant production requirements that would result from either methane-rich or oxygen-rich, methane-oxygen combustion. An elastic loop traction system that could be used for lunar construction vehicles was refined to permit testing. A parabolic heat rejection radiator system was designed and built to determine whether it was capable of increasing heat rejection rates during lunar daytime operation. In addition, an alternate space station truss design, utilizing a pre-integrated concept, was studied and found to reduce estimate extravehicular activity (EVA) time and increase the structural integrity when compared to the original Warren truss concept. An orbital-debris-capturing spacecraft design which could be mated with the Orbital Maneuvering Vehicle was studied. The design identified Soviet C-1B boosters as the best targets of opportunity in Earth orbits between an altitude of 900 km and 1100 km and at an inclination of 82.9 deg. A dual robot pallet, which could be spun to match the tumbling rate of the C-1B booster, was developed as the conceptual design.

  20. Evaluation of biomass combustion based energy systems by cumulative energy demand and energy yield coefficient

    Energy Technology Data Exchange (ETDEWEB)

    Nussbaumer, T.; Oser, M.

    2004-07-01

    This final report prepared for the International Energy Agency (IEA) Bioenergy Task 32 presents a method for a comparison of different energy systems with respect to the overall energy yield during their life cycles. For this purpose, the Cumulative Energy Demand (CED) based on primary energy and the Energy Yield Factor (EYC) are introduced and determined for the following scenarios: Log wood, wood chips, and wood pellets for residential heating and - except for log wood - also for district heating. As an alternative to heat production, power production via combustion and use of the electricity for decentralised heat pumps is also looked at. The evaluation and comparison of both the EYC for all fuels and the EYC{sub N}R for the non-renewable part enables a ranking of energy systems without a subjective weighing of non-renewable and renewable fuels to be made. For a sustainable energy supply, it is proposed to implement renewable energy systems in future which achieve an energy yield EYC{sub N}R of at least greater than 2 but favourably greater than 5. The evaluation of the different scenarios presented is proposed as the future basis for the choice of the most efficient energy systems based on biomass combustion.

  1. Control system for the carburettor of an internal combustion engine. Steuerungssystem fuer den Vergaser einer Brennkraftmaschine

    Energy Technology Data Exchange (ETDEWEB)

    Erhard, W.; Fluegel, W.

    1991-02-14

    Control system for the carburettor of an internal combustion engine, especially lawn-movers, powersaws or cutoff machines. At the entrance of the carburettor induction pipe there is a pre-throttle valve which is automatically operated by an actuator. The actuator can be operated by a pulse-width modulator whose pulse width or degree of modulation is influenced by a stored-program family of curves which generates signals for pre-specified fuel-air mixtures depending on the machine speed and sends these signals to the pulse-width modulator.

  2. New Turbo Compound Systems in Automotive Industry for Internal Combustion Engine to Recover Energy

    Science.gov (United States)

    Chiriac, R.; Chiru, A.; Condrea, O.

    2017-10-01

    The large amount of heat is scattered in the internal combustion engine through exhaust gas, coolant, convective and radiant heat transfer. Of all these residual heat sources, exhaust gases have the potential to recover using various modern heat recovery techniques. Waste heat recovery from an engine could directly reduce fuel consumption, increase available electrical power and improve overall system efficiency and if it would be used a turbochargers that can also produce energy. This solution is called turbo aggregation and has other ways to develop it in other areas of research like the electrical field. [1-3

  3. Calculation of thermal conductivity for new materials used in intake systems of internal combustion engines

    Science.gov (United States)

    Birtok-Bǎneasǎ, Corneliu; RaÅ£iu, Sorin Aurel; HepuÅ£, Teodor

    2017-07-01

    This paper presents a method for reduce thermal losses in the intake system of an internal combustion engine, whit improvement of airflow and thermal protection. The method consists in insulating the intake with a new kind of material. The present paper focuses on calculation of thermal conductivity for a new material developed by the authors, using the heat flux plate method. This experimental method consists in placing the sample of the new material in a calorimetric chamber and heating from underside. As the heat flux which passes through the sample material is constant and knowing the values of the temperatures for the both sides of sample, the sample material thermal conductivity is determined.

  4. Oxygen enriched combustion system performance study. Phase 2: 100 percent oxygen enriched combustion in regenerative glass melters, Final report

    Energy Technology Data Exchange (ETDEWEB)

    Tuson, G.B.; Kobayashi, H.; Campbell, M.J.

    1994-08-01

    The field test project described in this report was conducted to evaluate the energy and environmental performance of 100% oxygen enriched combustion (100% OEC) in regenerative glass melters. Additional objectives were to determine other impacts of 100% OEC on melter operation and glass quality, and to verify on a commercial scale that an on-site Pressure Swing Adsorption oxygen plant can reliably supply oxygen for glass melting with low electrical power consumption. The tests constituted Phase 2 of a cooperative project between the United States Department of Energy, and Praxair, Inc. Phase 1 of the project involved market and technical feasibility assessments of oxygen enriched combustion for a range of high temperature industrial heating applications. An assessment of oxygen supply options for these applications was also performed during Phase 1, which included performance evaluation of a pilot scale 1 ton per day PSA oxygen plant. Two regenerative container glass melters were converted to 100% OEC operation and served as host sites for Phase 2. A 75 ton per day end-fired melter at Carr-Lowrey Glass Company in Baltimore, Maryland, was temporarily converted to 100% OEC in mid- 1990. A 350 tpd cross-fired melter at Gallo Glass Company in Modesto, California was rebuilt for permanent commercial operation with 100% OEC in mid-1991. Initially, both of these melters were supplied with oxygen from liquid storage. Subsequently, in late 1992, a Pressure Swing Adsorption oxygen plant was installed at Gallo to supply oxygen for 100% OEC glass melting. The particular PSA plant design used at Gallo achieves maximum efficiency by cycling the adsorbent beds between pressurized and evacuated states, and is therefore referred to as a Vacuum/Pressure Swing Adsorption (VPSA) plant.

  5. Establishment of Combustion Model for Isooctane HCCI Marine Diesel Engine and Research on the Combustion Characteristic

    Directory of Open Access Journals (Sweden)

    Li Biao

    2016-01-01

    Full Text Available The homogeneous charge compression ignition (HCCI combustion mode applied in marine diesel engine is expected to be one of alternative technologies to decrease nitrogen oxide (NOX emission and improve energy utilization rate. Applying the chemical-looping combustion (CLC mechanism inside the cylinder, a numerical study on the HCCI combustion process is performed taking a marine diesel engine as application object. The characteristic feature of combustion process is displayed. On this basis, the formation and emission of NOX are analyzed and discussed. The results indicate that the HCCI combustion mode always exhibit two combustion releasing heats: low-temperature reaction and high-temperature reaction. The combustion phase is divided into low-temperature reaction zone, high-temperature reaction zone and negative temperature coefficient (NTC zone. The operating conditions of the high compression ratio, high intake air temperature, low inlet pressure and small excess air coefficient would cause the high in-cylinder pressure which often leads engine detonation. The low compression ratio, low intake air temperature and big excess air coefficient would cause the low combustor temperature which is conducive to reduce NOX emissions. These technological means and operating conditions are expected to meet the NOX emissions limits in MARPOL73/78 Convention-Annex VI Amendment.

  6. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. T. Nakamura; Dr. Miguel Olaizola; Dr. Stephen M. Masutani

    2002-07-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 April to 30 June 2001 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on the component optimization work. Aquasearch continued their effort on selection of microalgae suitable for CO{sub 2} sequestration. University of Hawaii initiated effort on system optimization of the CO{sub 2} sequestration system.

  7. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. T. Nakamura; Dr. Miguel Olaizola; Dr. Stephen M. Masutani

    2002-01-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report is the summary first year report covering the reporting period 1 October 2000 to 30 September 2001 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on the component optimization work. Aquasearch continued their effort on selection of microalgae suitable for CO{sub 2} sequestration. University of Hawaii initiated effort on system optimization of the CO{sub 2} sequestration system.

  8. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. T. Nakamura; Dr. Miguel Olaizola; Dr. Steven M. Masutani

    2001-08-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 April to 30 June 2001 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on the component optimization work. Aquasearch continued their effort on selection of microalgae suitable for CO{sub 2} sequestration. University of Hawaii initiated effort on system optimization of the CO{sub 2} sequestration system.

  9. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. T. Nakamura; Dr. Miguel Olaizola; Dr. Stephen M. Masutani

    2002-03-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 October to 31 December 2001 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on the component optimization work. Aquasearch continued their effort on selection of microalgae suitable for CO{sub 2} sequestration. University of Hawaii initiated effort on system optimization of the CO{sub 2} sequestration system.

  10. Evaluation of unthrottled combustion system options for light duty applications with future syncrude derived fuels. Alternative Fuels Utilization Program

    Energy Technology Data Exchange (ETDEWEB)

    Needham, J. R.; Cooper, B. M.; Norris-Jones, S. R.

    1982-12-01

    An experimental program examining the interaction between several fuel and light duty automotive engine combinations is detailed. Combustion systems addressed covered indirect and direct injection diesel and spark ignited stratified charge. Fuels primarily covered D2, naphtha and intermediate broadcut blends. Low ignition quality diesel fuels were also evaluated. The results indicate the baseline fuel tolerance of each combustion system and enable characteristics of the systems to be compared. Performance, gaseous and particulate emissions aspects were assessed. The data obtained assists in the selection of candidate combustion systems for potential future fuels. Performance and environmental penalties as appropriate are highlighted relative to the individual candidates. Areas of further work for increased understanding are also reviewed.

  11. Recovery and Sequestration of CO2 from Stationary Combustion Systems by Photosynthesis of Microalgae

    Energy Technology Data Exchange (ETDEWEB)

    T. Nakamura; C.L. Senior

    2005-04-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 October 2000 to 31 March 2005 in which PSI, Aquasearch and University of Hawaii conducted their tasks. This report discusses results of the work pertaining to five tasks: Task 1--Supply of CO2 from Power Plant Flue Gas to Photobioreactor; Task 2--Selection of Microalgae; Task 3--Optimization and Demonstration of Industrial Scale Photobioreactor; Task 4--Carbon Sequestration System Design; and Task 5--Economic Analysis. Based on the work conducted in each task summary conclusion is presented.

  12. LES SOFTWARE FOR THE DESIGN OF LOW EMISSION COMBUSTION SYSTEMS FOR VISION 21 PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Steven Cannon; Baifang Zuo; Virgil Adumitroaie; Keith McDaniel; Clifford Smith

    2002-04-30

    Further development of a combustion Large Eddy Simulation (LES) code for the design of advanced gaseous combustion systems is described in this sixth quarterly report. CFD Research Corporation (CFDRC) is developing the LES module within the parallel, unstructured solver included in the commercial CFD-ACE+ software. In this quarter, in-situ adaptive tabulation (ISAT) for efficient chemical rate storage and retrieval was implemented and tested within the Linear Eddy Model (LEM). ISAT type 3 is being tested so that extrapolation can be performed and further improve the retrieval rate. Further testing of the LEM for subgrid chemistry was performed for parallel applications and for multi-step chemistry. Validation of the software on backstep and bluff-body reacting cases were performed. Initial calculations of the SimVal experiment at Georgia Tech using their LES code were performed. Georgia Tech continues the effort to parameterize the LEM over composition space so that a neural net can be used efficiently in the combustion LES code. A new and improved Artificial Neural Network (ANN), with log-transformed output, for the 1-step chemistry was implemented in CFDRC's LES code and gave reasonable results. This quarter, the 2nd consortium meeting was held at CFDRC. Next quarter, LES software development and testing will continue. Alpha testing of the code will continue to be performed on cases of interest to the industrial consortium. Optimization of subgrid models will be pursued, particularly with the ISAT approach. Also next quarter, the demonstration of the neural net approach, for multi-step chemical kinetics speed-up in CFD-ACE+, will be accomplished.

  13. Fundamental characterization of alternate fuel effects in continuous combustion systems. Summary technical progress report, August 15, 1978-January 31, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Blazowski, W.S.; Edelman, R.B.; Wong, E.

    1980-02-27

    The overall objective of this contract is to assist in the development of fuel-flexible combustion systems for gas turbines as well as Rankine and Stirling cycle engines. The primary emphasis of the program is on liquid hydrocarbons produced from non-petroleum resources. Fuel-flexible combustion systems will provide for more rapid transition of these alternative fuels into important future energy utilization centers (especially utility power generation with the combined cycle gas turbine). The specific technical objectives of the program are: (a) develop an improved understanding of relationships between alternative fuel properties and continuous combustion system effects, and (b) provide analytical modeling/correlation capabilities to be used as design aids for development of fuel-tolerant combustion systems. This is the second major report of the program. Key experimental findings during this reporting period concern stirred combustor soot production during operation at controlled temperature conditions, soot production as a function of combustor residence time, an improved measurement technique for total hydrocarbons and initial stirred combustor results of fuel nitrogen conversion. While the results to be presented concern a stirred combustor which utilizes premixed fuel vapor/oxidant mixtures, a new combustor which combusts liquid fuel injected into the reactor as a spray has been developed and will be described. Analytical program progress includes the development of new quasiglobal models of soot formation and assessment of needs for other submodel development.

  14. Tomography system for measurement of gas properties in combustion flow field

    Directory of Open Access Journals (Sweden)

    Junling SONG

    2017-10-01

    Full Text Available This paper describes a self-designed fiber-coupled tomography system and its application in combustion diagnostics. The tomographic technique, which combines tunable diode laser spectroscopy and algebraic reconstruction technique, enables the simultaneous reconstruction of temperature and gas concentration with both spatial and temporal resolutions. The system measures a maximum diameter of 35 cm in a circular area with a minimum spatial resolution of 1 mm × 1 mm and temporal response of up to 1 kHz. Simulations validate the effects of the beam arrangement and discrete grid on reconstruction accuracy, and give the optimal beam arrangements. Experiments are made to demonstrate the tomography method, and systems are constructed in laboratory and on engineering test benches.

  15. Advanced coal-fueled industrial cogeneration gas turbine system -- combustion development

    Energy Technology Data Exchange (ETDEWEB)

    LeCren, R.T.

    1994-06-01

    This topical report summarizes the combustor development work accomplished under the subject contract. The objective was to develop a combustion system for the Solar 4MW Type H Centaur gas turbine generator set which was to be used to demonstrate the economic, technical and environmental feasibility of a direct coal-fueled gas turbine in a 100 hour proof-of-concept test. This program started with a design configuration derived during the CSC program. The design went through the following evolution: CSC design which had some known shortcomings, redesigned CSC now designated as the Two Stage Slagging Combustor (TSSC), improved TSSC with the PRIS evaluated in the IBSTF, and full scale design. Supporting and complimentary activities included computer modelling, flow visualization, slag removal, SO{sub x} removal, fuel injector development and fuel properties evaluation. Three combustor rigs were utilized: the TSSC, the IBSTF and the full scale rig at Peoria. The TSSC rig, which was 1/10th scale of the proposed system, consisted of a primary and secondary zone and was used to develop the primary zone performance and to evaluate SO{sub x} and slag removal and fuel properties variations. The IBSTF rig which included all the components of the proposed system was also 1/10th scale except for the particulate removal system which was about 1/30th scale. This rig was used to verify combustor performance data obtained on the TSSC and to develop the PRIS and the particulate removal system. The full scale rig initially included the primary and secondary zones and was later modified to incorporate the PRIS. The purpose of the full scale testing was to verify the scale up calculations and to provide a combustion system for the proof-of-concept engine test that was initially planned in the program.

  16. High temperature high velocity direct power extraction using an open-cycle oxy-combustion system

    Energy Technology Data Exchange (ETDEWEB)

    Love, Norman [Univ. of Texas, El Paso, TX (United States)

    2017-09-29

    The implementation of oxy-fuel technology in fossil-fuel power plants may contribute to increased system efficiencies and a reduction of pollutant emissions. One technology that has potential to utilize the temperature of undiluted oxy-combustion flames is open-cycle magnetohydrodynamic (MHD) power generators. These systems can be configured as a topping cycle and provide high enthalpy, electrically conductive flows for direct conversion of electricity. This report presents the design and modeling strategies of a MHD combustor operating at temperatures exceeding 3000 K. Throughout the study, computational fluid dynamics (CFD) models were extensively used as a design and optimization tool. A lab-scale 60 kWth model was designed, manufactured and tested as part of this project. A fully-coupled numerical method was developed in ANSYS FLUENT to characterize the heat transfer in the system. This study revealed that nozzle heat transfer may be predicted through a 40% reduction of the semi-empirical Bartz correlation. Experimental results showed good agreement with the numerical evaluation, with the combustor exhibiting a favorable performance when tested during extended time periods. A transient numerical method was employed to analyze fuel injector geometries for the 60-kW combustor. The ANSYS FLUENT study revealed that counter-swirl inlets achieve a uniform pressure and velocity ratio when the ports of the injector length to diameter ratio (L/D) is 4. An angle of 115 degrees was found to increase distribution efficiency. The findings show that this oxy-combustion concept is capable of providing a high-enthalpy environment for seeding, in order to render the flow to be conductive. Based on previous findings, temperatures in the range of 2800-3000 K may enable magnetohydrodynamic power extraction. The heat loss fraction in this oxy-combustion system, based on CFD and analytical calculations, at optimal operating conditions, was estimated to be less than 10 percent

  17. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. T. Nakamura; Dr. C.L. Senior

    2001-05-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 January to 31 March 2001 in which Aquasearch tested 24 different species of microalgae for growth at three different temperatures. Eleven species were analyzed for the presence of high-value pigments. Most of the algae analyzed were good sources of industrially valuable pigments. Analysis of the methods for introducing and dissolving CO{sub 2} in the commercial bioreactor was begun this quarter.

  18. RECOVERY AND SEQUESTRATION OF CO2 FROM STATIONARY COMBUSTION SYSTEMS BY PHOTOSYNTHESIS OF MICROALGAE

    Energy Technology Data Exchange (ETDEWEB)

    Dr. T. Nakamura; Dr. C.L. Senior

    2001-03-01

    Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period from 1 October to 31 December 2000. During this period planning of chemostat experiments at Aquasearch was initiated. These experiments will be used to select microalgae for the photobioreactor demonstrations. An initial survey of techniques for removing CO{sub 2} from coal-fired flue gas was begun. Chemical adsorption using MEA is the most mature technology and looks to be the most economically viable in the near future.

  19. System and method for conditioning intake air to an internal combustion engine

    Science.gov (United States)

    Sellnau, Mark C.

    2015-08-04

    A system for conditioning the intake air to an internal combustion engine includes a means to boost the pressure of the intake air to the engine and a liquid cooled charge air cooler disposed between the output of the boost means and the charge air intake of the engine. Valves in the coolant system can be actuated so as to define a first configuration in which engine cooling is performed by coolant circulating in a first coolant loop at one temperature, and charge air cooling is performed by coolant flowing in a second coolant loop at a lower temperature. The valves can be actuated so as to define a second configuration in which coolant that has flowed through the engine can be routed through the charge air cooler. The temperature of intake air to the engine can be controlled over a wide range of engine operation.

  20. Development and Testing of Industrial Scale Coal Fired Combustion System, Phase 3

    Energy Technology Data Exchange (ETDEWEB)

    Bert Zauderer

    1998-09-30

    Coal Tech Corp's mission is to develop, license & sell innovative, lowest cost, solid fuel fired power systems & total emission control processes using proprietary and patented technology for domestic and international markets. The present project 'DEVELOPMENT & TESTING OF INDUSTRIAL SCALE, COAL FIRED COMBUSTION SYSTEM, PHASE 3' on DOE Contract DE-AC22-91PC91162 was a key element in achieving this objective. The project consisted of five tasks that were divided into three phases. The first phase, 'Optimization of First Generation 20 MMBtu/hr Air-Cooled Slagging Coal Tech Combustor', consisted of three tasks, which are detailed in Appendix 'A' of this report. They were implemented in 1992 and 1993 at the first generation, 20 MMBtu/hour, combustor-boiler test site in Williamsport, PA. It consisted of substantial combustor modifications and coal-fired tests designed to improve the combustor's wall cooling, slag and ash management, automating of its operation, and correcting severe deficiencies in the coal feeding to the combustor. The need for these changes was indicated during the prior 900-hour test effort on this combustor that was conducted as part of the DOE Clean Coal Program. A combination of combustor changes, auxiliary equipment changes, sophisticated multi-dimensional combustion analysis, computer controlled automation, and series of single and double day shift tests totaling about 300 hours, either resolved these operational issues or indicated that further corrective changes were needed in the combustor design. The key result from both analyses and tests was that the combustor must be substantially lengthened to maximize combustion efficiency and sharply increase slag retention in the combustor. A measure of the success of these modifications was realized in the third phase of this project, consisting of task 5 entitled: 'Site Demonstration with the Second Generation 20 MMBtu/hr Air-Cooled Slagging Coal Tech

  1. Dynamic Exergy Method for Evaluating the Control and Operation of Oxy-Combustion Boiler Island Systems.

    Science.gov (United States)

    Jin, Bo; Zhao, Haibo; Zheng, Chuguang; Liang, Zhiwu

    2017-01-03

    Exergy-based methods are widely applied to assess the performance of energy conversion systems; however, these methods mainly focus on a certain steady-state and have limited applications for evaluating the control impacts on system operation. To dynamically obtain the thermodynamic behavior and reveal the influences of control structures, layers and loops, on system energy performance, a dynamic exergy method is developed, improved, and applied to a complex oxy-combustion boiler island system for the first time. The three most common operating scenarios are studied, and the results show that the flow rate change process leads to less energy consumption than oxygen purity and air in-leakage change processes. The variation of oxygen purity produces the largest impact on system operation, and the operating parameter sensitivity is not affected by the presence of process control. The control system saves energy during flow rate and oxygen purity change processes, while it consumes energy during the air in-leakage change process. More attention should be paid to the oxygen purity change because it requires the largest control cost. In the control system, the supervisory control layer requires the greatest energy consumption and the largest control cost to maintain operating targets, while the steam control loops cause the main energy consumption.

  2. System catalytic neutralization control of combustion engines waste gases in mining technologies

    Science.gov (United States)

    Korshunov, G. I.; Solnitsev, R. I.

    2017-10-01

    The paper presents the problems solution of the atmospheric air pollution with the exhaust gases of the internal combustion engines, used in mining technologies. Such engines are used in excavators, bulldozers, dump trucks, diesel locomotives in loading and unloading processes and during transportation of minerals. NOx, CO, CH emissions as the waste gases occur during engine operation, the concentration of which must be reduced to the standard limits. The various methods and means are used for the problem solution, one of which is neutralization based on platinum catalysts. A mathematical model of a controlled catalytic neutralization system is proposed. The simulation results confirm the increase in efficiency at start-up and low engine load and the increase in the catalyst lifetime.

  3. Part-load performance characteristics of a lean burn catalytic combustion gas turbine system

    Science.gov (United States)

    Yin, Juan; Li, Ming; Zhu, Jun-qiang

    2013-04-01

    The purpose of this study is to compare the part-load performance of a lean burn catalytic combustion gas turbine (LBCCGT) system in three different control modes: varying fuel, bleeding off the fuel mixture flow after the compressor and varying rotational speed. The conversions of methane species for chemical process are considered. A 1D heterogeneous plug flow model was utilized to analyze the system performance. The actual turbomachinery components were designed and predicted performance maps were applied to system performance research. The part-load characteristics under three control strategies were numerically investigated. The main results show that: the combustor inlet temperature is a significant factor that can significantly affect the part-load characteristics of the LBCCGT system; the rotational speed control mode can provide the best performance characteristics for part-load operations; the operation range of the bleed off mode is narrower than that of the speed control mode and wider than that of the fuel only mode; with reduced power, methane does not achieve full conversion over the reactor at the fuel only control mode, which will not warrant stable operation of the turbine system; the thermal efficiency of the LBCCGT system at fuel only control strategy is higher than that at bleed off control strategy within the operation range.

  4. Reference concepts for a space-based hydrogen-oxygen combustion, turboalternator, burst power system

    Energy Technology Data Exchange (ETDEWEB)

    Edenburn, M.W.

    1990-07-01

    This report describes reference concepts for a hydrogen-oxygen combustion, turboalternator power system that supplies power during battle engagement to a space-based, ballistic missile defense platform. All of the concepts are open''; that is, they exhaust hydrogen or a mixture of hydrogen and water vapor into space. We considered the situation where hydrogen is presumed to be free to the power system because it is also needed to cool the platform's weapon and the situation where hydrogen is not free and its mass must be added to that of the power system. We also considered the situation where water vapor is an acceptable exhaust and the situation where it is not. The combination of these two sets of situations required four different power generation systems, and this report describes each, suggests parameter values, and estimates masses for each of the four. These reference concepts are expected to serve as a baseline'' to which other types of power systems can be compared, and they are expected to help guide technology development efforts in that they suggest parameter value ranges that will lead to optimum system designs. 7 refs., 18 figs., 5 tabs.

  5. Applying Rock Engineering Systems (RES approach to Evaluate and Classify the Coal Spontaneous Combustion Potential in Eastern Alborz Coal Mines

    Directory of Open Access Journals (Sweden)

    Amir Saffari

    2013-12-01

    Full Text Available Subject analysis of the potential of spontaneous combustion in coal layers with analytical and numerical methods has been always considered as a difficult task because of the complexity of the coal behavior and the number of factors influencing it. Empirical methods, due to accounting for certain and specific factors, have not accuracy and efficiency for all positions. The Rock Engineering Systems (RES approach as a systematic method for analyzing and classifying is proposed in engineering projects. The present study is concerned with employing the RES approach to categorize coal spontaneous combustion in coal regions. Using this approach, the interaction of parameters affecting each other in an equal scale on the coal spontaneous combustion was evaluated. The Intrinsic, geological and mining characteristics of coal seams were studied in order to identifying important parameters. Then, the main stages of implementation of the RES method i.e. interaction matrix formation, coding matrix and forming a list category were performed. Later, an index of Coal Spontaneous Combustion Potential (CSCPi was determined to format the mathematical equation. Then, the obtained data related to the intrinsic, geological and mining, and special index were calculated for each layer in the case study (Pashkalat coal region, Iran. So, the study offers a perfect and comprehensive classification of the layers. Finally, by using the event of spontaneous combustion occurred in Pashkalat coal region, an initial validation for this systematic approach in the study area was conducted, which suggested relatively good concordance in Pashkalat coal region.

  6. How in-situ combustion process works in a fractured system : two-dimensional, core and block scale simulation

    Energy Technology Data Exchange (ETDEWEB)

    Fadaei, H.; Renard, G. [Inst. Francais du Petrole, Lyon (France); Quintard, M.; Debenest, G. [L' Inst. de Mecanique des Fluides de Toulouse, Toulouse (France); Kamp, A.M. [Centre Huile Lourde Ouvert et Experimental CHLOE, Pau (France)

    2008-10-15

    Core and matrix block scale simulations of in situ combustion (ISC) processes in a fractured reservoir were conducted. ISC propagation conditions and oil recovery mechanisms were studied at core scale, while the 2-D behaviour of ISC was also studied at block-scale in order to determine dominant processes for combustion propagation and the characteristics of different steam fronts. The study examined 2-phase combustion in a porous medium containing a solid fuel as well as 2-D conventional dry combustion methods. The aim of the study was to predict ISC extinction and propagation conditions as well as to understand the mechanisms of oil recovery using ISC processes. The simulations were also used to develop up-scaling guidelines for fractured systems. Computations were performed using different oxygen diffusion and matrix permeability values. The effect of each production mechanism was studied separately. The multi-phase simulations showed that ISC in fractured reservoirs is feasible. The study showed that ISC propagation is dependent on the oxygen diffusion coefficient, while matrix permeability plays an important role in oil production. Oil production was governed by gravity drainage and thermal effects. Heat transfer due to the movement of combustion front velocity in the study was minor when compared to heat transfer by conduction and convection. It was concluded that upscaling methods must also consider the different zones distinguished for oil saturation and temperatures. 15 refs., 2 tabs., 15 figs.

  7. Advanced combustion system for industrial boilers. Phase 2, Quarterly technical progress report, April--June 1991

    Energy Technology Data Exchange (ETDEWEB)

    Wagoner, C.L.; Foote, J.P.; Millard, W.P.; Attig, R.C.; Schulz, R.J.

    1991-12-31

    During this quarter, several coal combustion tests were carded out in the boiler using the eductor coal feed system and the two-stage combustor. The coal feed system and combustor are shown in Figures 2.1 and 2.2. The main goal for these tests was to determine the optimum combustor setup for low NO{sub x} emissions while maintaining good carbon conversion efficiency. It was found during the tests that the amount of air introduced into the combustor along with the coal through the eductor tailpipe was a critical parameter for both NO{sub x} formation and carbon conversion. Using the new fluidized coal hopper discharge arrangement, the air required for eductor operation varies from about 12 percent of the total combustion air at a 2 MBtu/h firing rate to about 8 percent at 4 and 6 MBtu/h. (During previous testing using the old coal tank, the eductor air requirement was about 12 percent at 4 MBtu/h.) In initial tests, only the amount of air needed for eductor operation was introduced through the tailpipe. Combustor operation under this condition was satisfactory at 2 MBtu/h but not at 4 or 6 MBtu/h. At 4 and 6 MBtu/h firing rates, carbon conversion was typically less than 98 percent (based on ash exiting the stack), and CO was relatively high. It was necessary to operate the combustor at a primary stoichiometry of 0.40 or less in order to meet the goal of 0.6 lb/MBtu for NO{sub x} emission.

  8. Fuel-Flexible Combustion System for Co-production Plant Applications

    Energy Technology Data Exchange (ETDEWEB)

    Joel Haynes; Justin Brumberg; Venkatraman Iyer; Jonathan Janssen; Ben Lacy; Matt Mosbacher; Craig Russell; Ertan Yilmaz; Williams York; Willy Ziminsky; Tim Lieuwen; Suresh Menon; Jerry Seitzman; Ashok Anand; Patrick May

    2008-12-31

    Future high-efficiency, low-emission generation plants that produce electric power, transportation fuels, and/or chemicals from fossil fuel feed stocks require a new class of fuel-flexible combustors. In this program, a validated combustor approach was developed which enables single-digit NO{sub x} operation for a future generation plants with low-Btu off gas and allows the flexibility of process-independent backup with natural gas. This combustion technology overcomes the limitations of current syngas gas turbine combustion systems, which are designed on a site-by-site basis, and enable improved future co-generation plant designs. In this capacity, the fuel-flexible combustor enhances the efficiency and productivity of future co-production plants. In task 2, a summary of market requested fuel gas compositions was created and the syngas fuel space was characterized. Additionally, a technology matrix and chemical kinetic models were used to evaluate various combustion technologies and to select two combustor concepts. In task 4 systems analysis of a co-production plant in conjunction with chemical kinetic analysis was performed to determine the desired combustor operating conditions for the burner concepts. Task 5 discusses the experimental evaluation of three syngas capable combustor designs. The hybrid combustor, Prototype-1 utilized a diffusion flame approach for syngas fuels with a lean premixed swirl concept for natural gas fuels for both syngas and natural gas fuels at FA+e gas turbine conditions. The hybrid nozzle was sized to accommodate syngas fuels ranging from {approx}100 to 280 btu/scf and with a diffusion tip geometry optimized for Early Entry Co-generation Plant (EECP) fuel compositions. The swozzle concept utilized existing GE DLN design methodologies to eliminate flow separation and enhance fuel-air mixing. With changing business priorities, a fully premixed natural gas & syngas nozzle, Protoytpe-1N, was also developed later in the program. It did

  9. Method for simultaneously removing SO.sub.2 and NO.sub.X pollutants from exhaust of a combustion system

    Science.gov (United States)

    Levendis, Yiannis A.; Wise, Donald L.

    1994-05-17

    A method is disclosed for removing pollutants from the exhaust of combustion systems burning fuels containing substantial amounts of sulfur and nitrogen. An exemplary method of the invention involves the formation and reaction of a sorbent comprising calcium magnesium acetate (CMA). The CMA is either dry-sprayed (in the form of a fine powder) or wet-sprayed in an aqueous solution in a high temperature environment such as a combustion chamber. The latter technique is feasible since CMA is a uniquely water-soluble form of calcium and magnesium. When the dispersed particles of CMA are heated to a high temperature, fine calcium and magnesium oxide particles, which are hollow with thin and highly porous walls are formed, affording optimum external and internal accessibility for reacting with toxic gaseous emissions such as SO.sub.2. Further, the combustion of the organic acetate portion of the sorbent results in the conversion of NO.sub.x to N.sub.2.

  10. Fuel-Rich Catalytic Combustion

    Science.gov (United States)

    Brabbs, Theodore A.; Olson, Sandra L.

    1987-01-01

    Two-stage combustion system reduces particulate emissions. Program on catalytic oxidation of iso-octane demonstrates feasibility of two-stage combustion system for reducing particulate emissions. With fuel-rich (fuel/air equivalence ratios of 4.8 to 7.8) catalytic-combustion preburner as first stage, combustion process free of soot at reactor-outlet temperatures of 1,200 K or less.

  11. SONOTECH, INC. FREQUENCY-TUNABLE PULSE COMBUSTION SYSTEM (CELLO PULSE BURNER) - INNOVATIVE TECHNOLOGY EVALUATION REPORT

    Science.gov (United States)

    Sonotech, Inc. (Sonotech) of Atlanta, Georgia, has developed a pulse combustion burner technology that claims to offer benefits when applied in a variety of combustion processes. The technology incorporates a combustor that can be tuned to induce large-amplitude acoustic or soni...

  12. Numerical investigation of one- and two-way fluid-structure interaction in combustion systems

    OpenAIRE

    Pozarlik, Artur Krzysztof; Kok, Jacobus B.W.; Oñate, E.; M. Papadrakakis; SCHREFLER, B.

    2007-01-01

    This paper presents numerical results of the fluid-structure investigation in a generic gas turbine combustion chamber. Results are obtained with the use of CFX-10 and ANSYS-10 commercial codes. The influence of the pressure changes inside the combustion chamber on the vibration pattern of the liner walls and vice versa is investigated.

  13. Numerical investigation of one- and two-way fluid-structure interaction in combustion systems

    NARCIS (Netherlands)

    Pozarlik, Artur Krzysztof; Kok, Jacobus B.W.; Oñate, E.; Papadrakakis, M.; Schrefler, B.

    2007-01-01

    This paper presents numerical results of the fluid-structure investigation in a generic gas turbine combustion chamber. Results are obtained with the use of CFX-10 and ANSYS-10 commercial codes. The influence of the pressure changes inside the combustion chamber on the vibration pattern of the liner

  14. LES SOFTWARE FOR THE DESIGN OF LOW EMISSION COMBUSTION SYSTEMS FOR VISION 21 PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Steve Cannon; Virgil Adumitroaie; Keith McDaniel; Cliff Smith

    2001-05-01

    Further development of a Large Eddy Simulation (LES) code for the design of advanced gaseous combustion systems is described in this second quarterly report. CFD Research Corporation (CFDRC) is developing the LES module within the parallel, unstructured solver included in the commercial CFD-ACE+ software. CFDRC has implemented and tested Smagorinsky and localized dynamic subgrid turbulence models on a 2.1 million cell DOE-NETL combustor case and a 400,000 cell nonreacting backstep case. Both cases showed good agreement between predicted and experimental results. The large DOE-NETL case results provided better agreement with the measured oscillation frequency than previous attempts because massive parallel computing (on a cluster of 24 pcs) allowed the entire computational domain, including the swirler vanes and fuel spokes, to be modeled. Subgrid chemistry models, including the conditional moment closure (CMC) and linear eddy model (LEM), are being tested and implemented. Reduced chemical mechanisms have been developed for emissions, ignition delay, extinction, and flame propagation using a computer automated reduction method (CARM). A 19-species natural gas mechanism, based on GRI2.11 and Miller-NO{sub x}, was shown to predict rich NO{sub x} emissions better than any previously published mechanisms. The ability to handle this mechanism in CFD-ACE+ was demonstrated by implementing operator splitting and a stiff ODE solver (DVODE). Efficient tabulation methods, including in situ adaptation and artificial neural nets, are being studied and will be implemented in the LES code. The LES combustion code development and testing is on schedule. Next quarter, initial results (including the DOE-NETL unstable combustor) with the CMC and LEM subgrid chemistry models will be completed and summarized.

  15. CO2 post-combustion capture in coal-fired power plants integrated with solar systems

    Science.gov (United States)

    Carapellucci, R.; Giordano, L.; Vaccarelli, M.

    2015-11-01

    The majority of the World's primary energy consumption is still based on fossil fuels, representing the largest source of global CO2 emissions. According to the Intergovernmental Panel on Climate Change (IPCC), such emissions must be significantly reduced in order to avoid the dramatic consequences of global warming. A potential way to achieve this ambitious goal is represented by the implementation of CCS (Carbon Capture and Storage) technologies. However, the significant amount of energy required by the CCS systems still represents one the major barriers for their deployment. Focusing on post-combustion capture based on amine absorption, several interesting options have been investigated to compensate the energy losses due to solvent regeneration, also using renewable energy sources. One of the most promising is based on the use of concentrating solar power (CSP), providing a part of the energy requirement of the capture island. In this study the integration of a CSP system into a coal-fired power plant with CO2 postcombustion capture is investigated. Basically, a CSP system is used to support the heat requirement for amine regeneration, by producing saturated steam at low temperature. This allows to reduce or even eliminate the conventional steam extraction from the main power plant, affecting positively net power production and efficiency. The energy analysis of the whole system is carried out using the GateCycle software to simulate the coal-fired power plant and ChemCad platform for the CO2 capture process based on amine absorption.

  16. Experimental and theoretical studies of iterative methods for nonlinear, nonsymmetric systems arising in combustion

    Energy Technology Data Exchange (ETDEWEB)

    Hagstrom, T. [Univ. of New Mexico, Albuquerque, NM (United States); Radhakrishnan, K. [Sverdrup Technology, Brook Park, OH (United States)

    1994-12-31

    The authors report on some iterative methods which they have tested for use in combustion simulations. In particular, they have developed a code to solve zero Mach number reacting flow equations with complex reaction and diffusion physics. These equations have the form of a nonlinear parabolic system coupled with constraints. In semi-discrete form, one obtains DAE`s of index two or three depending on the number of spatial dimensions. The authors have implemented a fourth order (fully implicit) BDF method in time, coupled with a suite of fourth order explicit and implicit spatial difference approximations. Most codes they know of for simulating reacting flows use a splitting strategy to march in time. This results in a sequence of nonlinear systems to solve, each of which has a simpler structure than the one they are faced with. The rapid and robust solution of the coupled system is the essential requirement for the success of their approach. They have implemented and analyzed nonlinear generalizations of conjugate gradient-like methods for nonsymmetric systems, including CGS and the quasi-Newton based method of Eirola and Nevanlinna. They develop a general framework for the nonlinearization of linear methods in terms of the acceleration of fixed-point iterations, where the latter is assumed to include the {open_quote}preconditioning{open_quote}. Their preconditioning is a single step of a split method, using lower order spatial difference approximations as well as simplified (Fickian) approximations of the diffusion physics.

  17. Smoldering Combustion

    OpenAIRE

    Rein, G

    2016-01-01

    Smoldering combustion is the slow, low temperature, flameless burning of porous fuels and is the most persistent type of combustion phenomena. It is especially common in porous fuels which form a char on heating, like cellulosic insulation, polyurethane foam or peat. Smoldering combustion is among the leading causes of residential fires, and it is a source of safety concerns in industrial premises as well as in commercial and space flights. Smoldering is also the dominant combustion phenomena...

  18. Fluidised Bed Combustion: A Novel Technology for the Combustion ...

    African Journals Online (AJOL)

    A firing technology, which is increasingly becoming popular for the combustion of fuels with difficult combustion properties, is fluidised bed combustion (FBC). In the current paper, the special features of FBC have been reviewed and their advantages as compared to conventional firing systems highlighted. This has been ...

  19. DRUCKFLAMM - Investigation on combustion and hot gas cleanup in pulverized coal combustion systems. Final report; DRUCKFLAMM - Untersuchungen zur Verbrennung und Heissgasreinigung bei der Druckkohlenstaubfeuerung. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Hein, K.R.G.; Benoehr, A.; Schuermann, H.; Stroehle, J.; Klaiber, C.; Kuhn, R.; Maier, J.; Schnell, U.; Unterberger, S.

    2001-07-01

    The ambitions of making energy supply more efficient and less polluting brought forth the development of coal based combined cycle power plants allowing considerable increases in net efficiencies. One of the regarded firing concepts for a coal based combined cycle power plant is represented by the pressurised pulverised coal combustion process which has the highest efficiency potential compared with the other coal based concepts. The fundamental purpose of the project was to gain firm knowledge concerning firing behaviour of coal in a pressurised pulverised coal combustion system. Detailed investigations were carried out in a pressurised entrained flow reactor taking into account fuel conversion and particle behaviour, pollutant formation and material behaviour under conditions of a pressurised pulverised coal firing. During the project's investigations several different measurement techniques were tested and partially also acquired (e.g. a two-colour-pyrometry system to measure simultaneous particle surface temperature and particle diameter of burning fuel particles). Calculation models under pressurised conditions for pressure vessel simulation and better scale-up were developed synchronously with the experimental investigations. The results gained using the pressurised entrained flow reactor show that many combustion mechanisms are influenced by increased pressure, for instance the fuel conversion is intensified and at the same time pollutant emissions decreased. The material investigations show that the ceramic materials used due to the very high combustion temperatures are very sensitive versus slagging and fast temperature changes, therefore further development requirements are needed to fully realise the high durability of ceramics in the pressurised furnace. Concerning the improvement of existing models for furnace simulation under pressurised conditions, a good resemblance can be observed when considering the actual measurement results from the test

  20. An internal combustion engine with ignition switch and induction system. Brennkraftmaschine mit einem Zuendschalter und einem Ansaugsystem

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, W.; Wolfram, H.J.

    1990-08-23

    The invention concerns an internal combustion engine with an ignition switch for the starter (on/off) and an induction system which has at least one main air filter, at least one carburettor and suction pipes for each cylinder of the internal combustion engine. It further includes a secondary suction line which opens into the main suction pipe and is activated by an actuator system. In order to cope with hot start problems of the engine the actuating system is designed in such a way that each time the engine is started atmospheric air is sucked in through the secondary induction pipe only thereby circumventing the section of the main induction line situated upstream of the actuator system.

  1. Oxygen Storage Properties of La 1–xSrxFeO3-δ for Chemical-Looping Reactions—An In Situ Neutron and Synchrotron X-ray Study

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Daniel D.; Schreiber, Nathaniel J.; Levitas, Benjamin D.; Xu, Wenqian; Whitfield, Pamela S.; Rodriguez, Efrain E.

    2016-06-14

    Oxygen storage materials (OSMs) provide lattice oxygen for a number of chemical-looping reactions including natural gas combustion and methane reforming. La1–xSrxFeO3-δ has shown promise for use as an OSM in methane reforming reactions due to its high product selectivity, fast oxide diffusion, and cycle stability. Here, we investigate the structural evolution of the series La1–xSrxFeO3-δ for x = 0, 1/3, 1/2, 2/3, and 1, using in situ synchrotron X-ray and neutron diffraction, as it is cycled under the conditions of a chemical-looping reactor (methane and oxygen atmospheres). In the compositions x = 1/3, 1/2, 2/3, and 1, we discover an envelope , or temperature range, of oxygen storage capacity (OSC), where oxygen can easily and reversibly be inserted and removed from the OSM. Our in situ X-ray and neutron diffraction results reveal that while samples with higher Sr contents had a higher OSC, those same samples suffered from slower reaction kinetics and some, such as the x = 1/2 and x = 2/3 compositions, had local variations in Sr content, which led to inhomogeneous regions with varying reaction rates. Therefore, we highlight the importance of in situ diffraction studies, and we propose that these measurements are required for the thorough evaluation of future candidate OSMs. Furthermore, we recommend La2/3Sr1/3FeO3-δ as the optimal OSM in the series because its structure remains homogeneous throughout the reaction, and its OSC envelope is similar to that of the higher doped materials.

  2. Development of an Organic Rankine Cycle system for exhaust energy recovery in internal combustion engines

    Science.gov (United States)

    Cipollone, Roberto; Bianchi, Giuseppe; Gualtieri, Angelo; Di Battista, Davide; Mauriello, Marco; Fatigati, Fabio

    2015-11-01

    Road transportation is currently one of the most influencing sectors for global energy consumptions and CO2 emissions. Nevertheless, more than one third of the fuel energy supplied to internal combustion engines is still rejected to the environment as thermal waste at the exhaust. Therefore, a greater fuel economy might be achieved recovering the energy from exhaust gases and converting it into useful power on board. In the current research activity, an ORC-based energy recovery system was developed and coupled with a diesel engine. The innovative feature of the recovery power unit relies upon the usage of sliding vane rotary machines as pump and expander. After a preliminary exhaust gas mapping, which allowed to assess the magnitude of the thermal power to be recovered, a thermodynamic analysis was carried out to design the ORC system and the sliding vane machines using R236fa as working fluid. An experimental campaign was eventually performed at different operating regimes according to the ESC procedure and investigated the recovery potential of the power unit at design and off-design conditions. Mechanical power recovered ranged from 0.7 kW up to 1.9 kW, with an overall cycle efficiency from 3.8% up to 4.8% respectively. These results candidate sliding vane machines as efficient and reliable devices for waste heat recovery applications.

  3. New approaches to the design of the combustion system for thermophotovoltaic applications

    Science.gov (United States)

    Colangelo, G.; de Risi, A.; Laforgia, D.

    2003-05-01

    A thermophotovoltaic (TPV) generator for electric vehicles has been designed and developed. In this paper we focus on the combustion system and the heat regenerator. The system has been designed to work as a range extender for electric vehicles. This solution would provide energy always available on the vehicle, which would run even if the battery level were low. Several configurations for the burner and for the heat exchanger have been investigated and a comparison of these is presented. The different solutions have been studied both theoretically and experimentally. In this paper, we report on the work carried out to build a TPV device capable of yielding 6 kW of electric power to recharge the battery pack of an electric city-car. The project has been divided into four steps: (1) pre-design of different configurations of the burner and heat exchanger using non-commercial software 'TPV Design Tool 1.0'; (2) testing of the pre-designed generators with a CFD code (Fluent 6); (3) testing of the chosen configurations on the experimental bench to validate the results from CFD simulations and to highlight technological limits of the chosen configurations; (4) selection of the best configuration. After the design and testing of the devices, a two-burner modular configuration has been proven to be a good compromise between the geometric constraints and the objectives of the project. The designed generator is relatively compact and light with good efficiency and emissions performance.

  4. Intelligent Control via Wireless Sensor Networks for Advanced Coal Combustion Systems

    Energy Technology Data Exchange (ETDEWEB)

    Aman Behal; Sunil Kumar; Goodarz Ahmadi

    2007-08-05

    Numerical Modeling of Solid Gas Flow, System Identification for purposes of modeling and control, and Wireless Sensor and Actor Network design were pursued as part of this project. Time series input-output data was obtained from NETL's Morgantown CFB facility courtesy of Dr. Lawrence Shadle. It was run through a nonlinear kernel estimator and nonparametric models were obtained for the system. Linear and first-order nonlinear kernels were then utilized to obtain a state-space description of the system. Neural networks were trained that performed better at capturing the plant dynamics. It is possible to use these networks to find a plant model and the inversion of this model can be used to control the system. These models allow one to compare with physics based models whose parameters can then be determined by comparing them against the available data based model. On a parallel track, Dr. Kumar designed an energy-efficient and reliable transport protocol for wireless sensor and actor networks, where the sensors could be different types of wireless sensors used in CFB based coal combustion systems and actors are more powerful wireless nodes to set up a communication network while avoiding the data congestion. Dr. Ahmadi's group studied gas solid flow in a duct. It was seen that particle concentration clearly shows a preferential distribution. The particles strongly interact with the turbulence eddies and are concentrated in narrow bands that are evolving with time. It is believed that observed preferential concentration is due to the fact that these particles are flung out of eddies by centrifugal force.

  5. Modelling of coal combustion enhanced through plasma-fuel systems in full-scale boilers

    Energy Technology Data Exchange (ETDEWEB)

    A.S. Askarova; Z. Jankoski; E.I. Karpenko; E.I. Lavrischeva; F.C. Lockwood; V.E. Messerle; A.B. Ustimenko [al-Farabi Kazakh National University, Almaty (Kazakhstan). Department of Physics

    2005-07-01

    Plasma activation promotes more effective and environmental friendly low-rank coal combustion. This work presents numerical modelling results of plasma thermochemical preparation of pulverized coal for ignition and combustion in the furnace of a utility boiler. Two kinetic mathematical models were used in the investigation of the processes of air-fuel mixture plasma activation, ignition and combustion. A 1D kinetic code, PLASMA-COAL, calculates the concentrations of species, temperatures and velocities of treated coal-air mixtures in a burner incorporating a plasma source. It gives initial data for 3D-modeling of power boilers furnaces by the code FLOREAN. A comprehensive image of plasma activated coal combustion processes in a furnace of pulverised coal fired boiler was obtained. The advantages of the plasma technology are clearly demonstrated. 15 refs., 6 figs., 4 tabs.

  6. Performance and combustion analysis of Mahua biodiesel on a single cylinder compression ignition engine using electronic fuel injection system

    Directory of Open Access Journals (Sweden)

    Gunasekaran Anandkumar

    2016-01-01

    Full Text Available In this investigation, experiment is carried out on a 1500 rpm constant speed single cylinder Diesel engine. The test is carried out with Neat diesel, neat biodiesel, and blend B20. The engine considered was run with electronic fuel injection system supported by common rail direct injection to obtain high atomization and effective air utilization inside the combustion chamber. The performance of the engine in terms of break thermal efficiency and brake specific energy consumption was found and compared. The B20 blend shows 1.11% decrease in break thermal efficiency and 3.35% increase in brake specific energy consumption than diesel. The combustion characteristics found are in-cylinder pressure, rate of pressure rise, and heat release rate and compared for peak pressure load to understand the nature of combustion process. For each fuel test run, the maximum peak pressure is observed at part load condition. The rate of change of pressure and heat release rate of diesel is high compared to pure biodiesel and B20 blend. The diffusion combustion is observed to be predominant in case of B100 than B20 and Neat diesel.

  7. Innovative Calibration Method for System Level Simulation Models of Internal Combustion Engines

    Directory of Open Access Journals (Sweden)

    Ivo Prah

    2016-09-01

    Full Text Available The paper outlines a procedure for the computer-controlled calibration of the combined zero-dimensional (0D and one-dimensional (1D thermodynamic simulation model of a turbocharged internal combustion engine (ICE. The main purpose of the calibration is to determine input parameters of the simulation model in such a way as to achieve the smallest difference between the results of the measurements and the results of the numerical simulations with minimum consumption of the computing time. An innovative calibration methodology is based on a novel interaction between optimization methods and physically based methods of the selected ICE sub-systems. Therein physically based methods were used for steering the division of the integral ICE to several sub-models and for determining parameters of selected components considering their governing equations. Innovative multistage interaction between optimization methods and physically based methods allows, unlike the use of well-established methods that rely only on the optimization techniques, for successful calibration of a large number of input parameters with low time consumption. Therefore, the proposed method is suitable for efficient calibration of simulation models of advanced ICEs.

  8. Beta Testing of CFD Code for the Analysis of Combustion Systems

    Science.gov (United States)

    Yee, Emma; Wey, Thomas

    2015-01-01

    A preliminary version of OpenNCC was tested to assess its accuracy in generating steady-state temperature fields for combustion systems at atmospheric conditions using three-dimensional tetrahedral meshes. Meshes were generated from a CAD model of a single-element lean-direct injection combustor, and the latest version of OpenNCC was used to calculate combustor temperature fields. OpenNCC was shown to be capable of generating sustainable reacting flames using a tetrahedral mesh, and the subsequent results were compared to experimental results. While nonreacting flow results closely matched experimental results, a significant discrepancy was present between the code's reacting flow results and experimental results. When wide air circulation regions with high velocities were present in the model, this appeared to create inaccurately high temperature fields. Conversely, low recirculation velocities caused low temperature profiles. These observations will aid in future modification of OpenNCC reacting flow input parameters to improve the accuracy of calculated temperature fields.

  9. Variable oxygen/nitrogen enriched intake air system for internal combustion engine applications

    Science.gov (United States)

    Poola, Ramesh B.; Sekar, Ramanujam R.; Cole, Roger L.

    1997-01-01

    An air supply control system for selectively supplying ambient air, oxygen enriched air and nitrogen enriched air to an intake of an internal combustion engine includes an air mixing chamber that is in fluid communication with the air intake. At least a portion of the ambient air flowing to the mixing chamber is selectively diverted through a secondary path that includes a selectively permeable air separating membrane device due a differential pressure established across the air separating membrane. The permeable membrane device separates a portion of the nitrogen in the ambient air so that oxygen enriched air (permeate) and nitrogen enriched air (retentate) are produced. The oxygen enriched air and the nitrogen enriched air can be selectively supplied to the mixing chamber or expelled to atmosphere. Alternatively, a portion of the nitrogen enriched air can be supplied through another control valve to a monatomic-nitrogen plasma generator device so that atomic nitrogen produced from the nitrogen enriched air can be then injected into the exhaust of the engine. The oxygen enriched air or the nitrogen enriched air becomes mixed with the ambient air in the mixing chamber and then the mixed air is supplied to the intake of the engine. As a result, the air being supplied to the intake of the engine can be regulated with respect to the concentration of oxygen and/or nitrogen.

  10. On-board diagnostics of fully variable valve actuator systems in spark-ignited combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Sarac, Ipek

    2010-07-01

    Variable valve actuation (VVA) is being employed in contemporary engines to improve fuel consumption, torque characteristics and emissions of combustion engines by enabling the realization of different combustion strategies. Fully variable valve actuation (FVVA) makes it possible to apply a wider range of strategies (e.g., homogenous charge compression ignition (HCCI), dethrottling, internal residual gas mechanism, 2/4 Stroke Switching). With FVVA, the gas exchange valves can be actuated at arbitrary points in time, with separate variable lifting for the intake and exhaust valves of each cylinder. Making FVVA systems ready for the market requires to provide the system with appropriate fault-diagnostic functionality. Additional degrees of freedom of FVVA systems introduce different fault cases which have to be considered in terms of their emission relevance within the scope of diagnostics standards such as On-Board Diagnosis II (OBD II). The faults and their effects on emissions have not been analyzed by any other study, yet. To fill this gab, here the possible faults are generated using a four-cylinder gasoline camless test bench engine. Measurements are carried out using different strategies at low loads, namely dethrottling with early intake valve closing and combining high internal residual gas with dethrottling. Each fault case is thoroughly analyzed, and the emission-relevant faults are pointed out for initial consideration. A trivial approach to diagnose fully variable valve actuators is to introduce position sensors for each actuator to track the valve lift curve. However, this approach increases the cost of the system undesirably. Thus, here alternative methods are explored such as indirect use of common powertrain sensors. Considering that active diagnosis may lead to suboptimal engine control schemes, the possibilities of fault detection and isolation are investigated without relying on active diagnosis. Air path sensors are affected foremost by any

  11. Submerged combustion melting processes for producing glass and similar materials, and systems for carrying out such processes

    Science.gov (United States)

    Charbonneau, Mark William

    2015-08-04

    Processes of controlling submerged combustion melters, and systems for carrying out the methods. One process includes feeding vitrifiable material into a melter vessel, the melter vessel including a fluid-cooled refractory panel in its floor, ceiling, and/or sidewall, and heating the vitrifiable material with a burner directing combustion products into the melting zone under a level of the molten material in the zone. Burners impart turbulence to the molten material in the melting zone. The fluid-cooled refractory panel is cooled, forming a modified panel having a frozen or highly viscous material layer on a surface of the panel facing the molten material, and a sensor senses temperature of the modified panel using a protected thermocouple positioned in the modified panel shielded from direct contact with turbulent molten material. Processes include controlling the melter using the temperature of the modified panel. Other processes and systems are presented.

  12. Application of a high-repetition-rate laser diagnostic system for single-cycle-resolved imaging in internal combustion engines.

    Science.gov (United States)

    Hult, Johan; Richter, Mattias; Nygren, Jenny; Aldén, Marcus; Hultqvist, Anders; Christensen, Magnus; Johansson, Bengt

    2002-08-20

    High-repetition-rate laser-induced fluorescence measurements of fuel and OH concentrations in internal combustion engines are demonstrated. Series of as many as eight fluorescence images, with a temporal resolution ranging from 10 micros to 1 ms, are acquired within one engine cycle. A multiple-laser system in combination with a multiple-CCD camera is used for cycle-resolved imaging in spark-ignition, direct-injection stratified-charge, and homogeneous-charge compression-ignition engines. The recorded data reveal unique information on cycle-to-cycle variations in fuel transport and combustion. Moreover, the imaging system in combination with a scanning mirror is used to perform instantaneous three-dimensional fuel-concentration measurements.

  13. High-Efficiency Low-Dross Combustion System for Aluminum Remelting Reverberatory Furnaces, Project Final Report, July 2005

    Energy Technology Data Exchange (ETDEWEB)

    Soupos, V.; Zelepouga, S.; Rue, D.

    2005-06-30

    GTI, and its commercial partners, have developed a high-efficiency low-dross combustion system that offers environmental and energy efficiency benefits at lower capital costs for the secondary aluminum industry users of reverberatory furnaces. The high-efficiency low-dross combustion system, also called Self-Optimizing Combustion System (SOCS), includes the flex-flame burner firing an air or oxygen-enriched natural gas flame, a non-contact optical flame sensor, and a combustion control system. The flex-flame burner, developed and tested by GTI, provides an innovative firing process in which the flame shape and velocity can be controlled. The burner produces a flame that keeps oxygen away from the bath surface by including an O2-enriched fuel-rich zone on the bottom and an air-fired fuel-lean zone on the top. Flame shape and velocity can be changed at constant firing rate or held constant over a range of firing conditions. A non-intrusive optical sensor is used to monitor the flame at all times. Information from the optical sensor(s) and thermocouples can be used to control the flow of natural gas, air, and oxygen to the burner as needed to maintain desired flame characteristics. This type of control is particularly important to keep oxygen away from the melt surface and thus reduce dross formation. This retrofit technology decreases fuel usage, increases furnace production rate, lowers gaseous emissions, and reduces dross formation. The highest priority research need listed under Recycled Materials is to turn aluminum process waste into usable materials which this technology accomplishes directly by decreasing dross formation and therefore increasing aluminum yield from a gas-fired reverberatory furnace. Emissions of NOx will be reduced to approximately 0.3 lb/ton of aluminum, in compliance with air emission regulations.

  14. An experimental study on the combustion characteristics of a catalytic combustor for an MCFC power generation system

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Dong Jin [Hyosung Corporation, Sejong (Korea, Republic of); Ahn, Kook Young [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of); Kim, Man Young [Chonbuk Nat' l Univ., Jeonju (Korea, Republic of)

    2012-04-15

    In the MCFC power generation system, the combustor supplies a high temperature mixture of gases to the cathode and heat to the reformer by using the off gas from the anode; the off gas includes high concentrations of H{sub 2}O and CO{sub 2}. Since a combustor needs to be operated in a very lean condition and avoid local heating, a catalytic combustor is usually adopted. Catalytic combustion is also generally accepted as one of the environmentally preferred alternatives for generation of heat and power from fossil fuels because of its complete combustion and low emissions of pollutants such as CO, UHC, and NO{sub x}. In this study, experiments were conducted on catalytic combustion behavior in the presence of Pd based catalysts for the BOP (Balance Of Plant) of 5kW MCFC (Molten Carbonate Fuel Cell) power generation systems. Extensive investigations were carried out on the catalyst performance with the gaseous CH{sub 4} fuel by changing such various parameters as H{sub 2} addition, inlet temperature, excess air ratio, space velocity, catalyst type, and start up schedule of the pilot system adopted in the BOP.

  15. Measures for a quality combustion (combustion chamber exit and downstream); Mesures pour une combustion de qualite (sortie de chambre de combustion et en aval)

    Energy Technology Data Exchange (ETDEWEB)

    Epinat, G. [APAVE Lyonnaise, 69 (France)

    1996-12-31

    After a review of the different pollutants related to the various types of stationary and mobile combustion processes (stoichiometric, reducing and oxidizing combustion), measures and analyses than may be used to ensure the quality and efficiency of combustion processes are reviewed: opacimeters, UV analyzers, etc. The regulation and control equipment for combustion systems are then listed, according to the generator capacity level

  16. Combustion engineering

    CERN Document Server

    Ragland, Kenneth W

    2011-01-01

    Introduction to Combustion Engineering The Nature of Combustion Combustion Emissions Global Climate Change Sustainability World Energy Production Structure of the Book   Section I: Basic Concepts Fuels Gaseous Fuels Liquid Fuels Solid Fuels Problems Thermodynamics of Combustion Review of First Law Concepts Properties of Mixtures Combustion StoichiometryChemical EnergyChemical EquilibriumAdiabatic Flame TemperatureChemical Kinetics of CombustionElementary ReactionsChain ReactionsGlobal ReactionsNitric Oxide KineticsReactions at a Solid SurfaceProblemsReferences  Section II: Combustion of Gaseous and Vaporized FuelsFlamesLaminar Premixed FlamesLaminar Flame TheoryTurbulent Premixed FlamesExplosion LimitsDiffusion FlamesGas-Fired Furnaces and BoilersEnergy Balance and EfficiencyFuel SubstitutionResidential Gas BurnersIndustrial Gas BurnersUtility Gas BurnersLow Swirl Gas BurnersPremixed-Charge Engine CombustionIntroduction to the Spark Ignition EngineEngine EfficiencyOne-Zone Model of Combustion in a Piston-...

  17. Combustion of refuse-derived fuels in the GAVI-VAM system at Wijster; Verbrennung von RDF - Ersterfahrungen aus der GAVI-VAM (Wijster)

    Energy Technology Data Exchange (ETDEWEB)

    Wandschneider, J.; Warnek, J.; Klitzbe, H.J.

    1997-12-31

    The GAVI-VAM system consists of a sorting stage followed by a RDF combustion plant. The two parts are directly connected by an RDF bunker (24 h). The contribution presents a detailed description of the plant. (orig./AKF)

  18. Method of air preheating for combustion power plant and systems comprising the same

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wei

    2017-12-12

    Disclosed herein is a heat exchanger for transferring heat between a first gas flow and a second gas flow, the heat exchanger comprising at least two sectors; a first sector that is operative to receive a combustion air stream; and a second sector that is opposed to the first sector and that is operative to receive either a reducer gas stream or an oxidizer gas stream, and a pressurized layer disposed between the first sector and the second sector; where the pressurized layer is at a higher pressure than combustion air stream, the reducer gas stream and the oxidizer gas stream.

  19. Transformations of inorganic coal constituents in combustion systems. Volume 2, Sections 6 and 7: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Helble, J.J. [ed.; Srinivasachar, S.; Wilemski, G.; Boni, A.A. [PSI Technology Co., Andover, MA (United States); Kang, Shin-Gyoo; Sarofim, A.F.; Graham, K.A.; Beer, J.M. [Massachusetts Inst. of Tech., Cambridge, MA (United States); Peterson, T.W.; Wendt, J.O.L.; Gallagher, N.B.; Bool, L. [Arizona Univ., Tucson, AZ (United States); Huggins, F.E.; Huffman, G.P.; Shah, N.; Shah, A. [Kentucky Univ., Lexington, KY (United States)

    1992-11-01

    Results from an experimental investigation of the mechanisms governing the ash aerosol size segregated composition resulting from the combustion of pulverized coal in a laboratory scale down-flow combustor are described. The results of modeling activities used to interpret the results of the experiments conducted under his subtask are also described in this section. Although results from the entire program are included, Phase II studies which emphasized: (1) alkali behavior, including a study of the interrelationship between potassium vaporization and sodium vaporization; and (2) iron behavior, including an examination of the extent of iron-aluminosilicate interactions, are highlighted. Idealized combustion determination of ash particle formation and surface stickiness are also described.

  20. Contact diagnostics of combustion products of rocket engines, their units, and systems

    Science.gov (United States)

    Ivanov, N. N.; Ivanov, A. N.

    2013-12-01

    This article is devoted to a new block-module device used in the diagnostics of condensed combustion products of rocket engines during research and development with liquid-propellant rocket engines (Glushko NPO Energomash; engines RD-171, RD-180, and RD-191) and solid-propellant rocket motors. Soot samplings from the supersonic high-temperature jet of a high-power liquid-propellant rocket engine were taken by the given device for the first time in practice for closed-exhaust lines. A large quantity of significant results was also obtained during a combustion investigation of solid propellants within solid-propellant rocket motors.

  1. Transition duct system with arcuate ceramic liner for delivering hot-temperature gases in a combustion turbine engine

    Energy Technology Data Exchange (ETDEWEB)

    Wiebe, David J.

    2017-11-07

    A transition duct system (10) for delivering hot-temperature gases from a plurality of combustors in a combustion turbine engine is provided. The system includes an exit piece (16) for each combustor. The exit piece may include an arcuate connecting segment (36). An arcuate ceramic liner (60) may be inwardly disposed onto a metal outer shell (38) along the arcuate connecting segment of the exit piece. Structural arrangements are provided to securely attach the ceramic liner in the presence of substantial flow path pressurization. Cost-effective serviceability of the transition duct systems is realizable since the liner can be readily removed and replaced as needed.

  2. Application of advanced laser diagnostics to hypersonic wind tunnels and combustion systems.

    Energy Technology Data Exchange (ETDEWEB)

    North, Simon W. (Texas A& M University, College Station, TX); Hsu, Andrea G. (Texas A& M University, College Station, TX); Frank, Jonathan H.

    2009-09-01

    This LDRD was a Sandia Fellowship that supported Andrea Hsu's PhD research at Texas A&M University and her work as a visitor at Sandia's Combustion Research Facility. The research project at Texas A&M University is concerned with the experimental characterization of hypersonic (Mach>5) flowfields using experimental diagnostics. This effort is part of a Multidisciplinary University Research Initiative (MURI) and is a collaboration between the Chemistry and Aerospace Engineering departments. Hypersonic flight conditions often lead to a non-thermochemical equilibrium (NTE) state of air, where the timescale of reaching a single (equilibrium) Boltzmann temperature is much longer than the timescale of the flow. Certain molecular modes, such as vibrational modes, may be much more excited than the translational or rotational modes of the molecule, leading to thermal-nonequilibrium. A nontrivial amount of energy is therefore contained within the vibrational mode, and this energy cascades into the flow as thermal energy, affecting flow properties through vibrational-vibrational (V-V) and vibrational-translational (V-T) energy exchanges between the flow species. The research is a fundamental experimental study of these NTE systems and involves the application of advanced laser and optical diagnostics towards hypersonic flowfields. The research is broken down into two main categories: the application and adaptation of existing laser and optical techniques towards characterization of NTE, and the development of new molecular tagging velocimetry techniques which have been demonstrated in an underexpanded jet flowfield, but may be extended towards a variety of flowfields. In addition, Andrea's work at Sandia National Labs involved the application of advanced laser diagnostics to flames and turbulent non-reacting jets. These studies included quench-free planar laser-induced fluorescence measurements of nitric oxide (NO) and mixture fraction measurements via Rayleigh

  3. Control of the self-oscillation of amplitude of vibration combustion in a liquid-propellant rocket engine by solving the system of equations that describe this regime of combustion

    Science.gov (United States)

    Gotsulenko, V. V.

    2010-07-01

    Periodic solutions of the degenerate system of equations of nonstationary motion of a medium in a liquid-propellant rocket engine were obtained, with the aid of which the possibility of lowering the amplitude of the longitudinal self-oscillations of vibration combustion or their complete removal has been substantiated.

  4. Release of alkali salts and coal volatiles affecting internal components in fluidized bed combustion systems

    Directory of Open Access Journals (Sweden)

    Arias del Campo, E.

    2003-12-01

    Full Text Available In spite of the potential advantages of atmospheric fluidized bed systems, experience has proved that, under certain environments and operating conditions, a given material employed for internal components could lead to catastrophic events. In this study, an attempt is made to establish material selection and operational criteria that optimize performance and availability based on theoretical considerations of the bed hydrodynamics, thermodynamics and combustion process. The theoretical results may indicate that, for high-volatile coals with particle diameters (dc of 1-3 mm and sand particle size (ds of 0.674 mm, a considerable proportion of alkali chlorides may be transferred into the freeboard region of fluidized bed combustors as vapor phase, at bed temperatures (Tb < 840 °C, excess air (XSA ≤ 20 %, static bed height (Hs ≤ 0.2 m and fluidizing velocity (Uo < 1 m/s. Under these operating conditions, a high alkali deposition may be expected to occur in heat exchange tubes located above the bed. Conversely, when the combustors operate at Tb > 890 °C and XSA > 30 %, a high oxidation rate of the in-bed tubes may be present. Nevertheless, for these higher Tb values and XSA < 10 %, corrosion attack of metallic components, via sulfidation, would occur since the excessive gas-phase combustion within the bed induced a local oxygen depletion.

    A pesar de las ventajas potenciales de los sistemas atmosféricos de lecho fluidizado, la experiencia ha demostrado que, bajo ciertas atmósferas y condiciones de operación, un material que se emplea como componente interno podría experimentar una falla y conducir a eventos catastróficos. En este estudio, se intenta establecer un criterio tanto operativo como de selección del material que permita optimizar su disponibilidad y funcionalidad basados en consideraciones teóricas de la hidrodinámica del lecho, la termodin

  5. Fuel-rich hydrogen-air combustion for a gas-turbine system without CO{sub 2} emission

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Noriyuki; Namo, Takamitsu; Arai, Norio [Nagoya Univ. (Japan). Research Center for Advanced Energy Conversion

    1997-02-01

    We propose a new and innovative gas-turbine system using fuel-rich hydrogen combustion, which we call a chemical gas-turbine system. It involves a fuel-rich hydrogen-air combustor as a major component. We have focused on a coaxial diffusion flame under normal pressure. The effects of equivalence ratio and swirl number have been investigated by measuring temperature profiles, gas composition, and flame structures using direct observations of OH radical emissions. The flames were shortened and NO{sub x} emission decreased with swirling under fuel-rich conditions. (author)

  6. Design and implementation of a control system to improve the quality of the combustion gases in the fire-tube boiler of 5 BHP

    Directory of Open Access Journals (Sweden)

    Carlos Alfredo Pérez Albán

    2016-06-01

    Full Text Available The goal of this paper is the design and implementation of a system for controlling the quality of the combustion gases in a fire-tube boiler of 5 BHP. Based on the percentage of O2 present in the combustion gases, measured by a lambda sensor, the percentage of CO2 emitted into the atmosphere is determined. PID proportional control is responsible for the automatic regulation of the entry of air to the boiler by an actuator, according to the percentage of the oxygen concentration in the combustion gases. The control system has an HMI display and a modular PLC. The results achieved ensure pollutant gases emissions within the parameters established by current environmental standards, achieving the required quality of combustion gases and reducing the fuel consumption of the boiler.

  7. Engineering systems analysis of pressurized fluidized-bed-combustion power systems

    Energy Technology Data Exchange (ETDEWEB)

    Graves, R.L.; Griffin, F.P.; Lackey, M.E.

    1982-04-01

    This effort was conducted to provde supporting data for the research and development program on pressurized fluidized bed combustor (PFBC) systems being continued under the auspices of the Office of Coal Utilization of DOE. This report deals with the first phase of the effort, designated Task 1, which was scoped to be a somewhat broad review of PFBC technology and an analysis to determine its potential and sensitivity to key development needs. Background information pertaining to the application of PFBC to the market for coal-fired technology is included. The status of development is reviewed and the deficiencies in data are identified. Responses to a survey of PFBC developers are reviewed with emphasis on the high risk areas of the PFBC concept. Some of these problems are: uncertainty of life of gas turbine components; lack of demonstration of load following; and hot solids handling. Some high risk areas, such as the gas cleanup or gas turbine systems, can be relieved by reducing the severity of design conditions such as the turbine inlet temperature. Alternate turbine designs or plant configurations are also possible solutions. Analyses were performed to determine whether the advantages held by PFBC systems in cost, efficiency, and emissions would be nullified by measures taken to reduce risk. In general, the results showed that the attractive features of the PFBC could be preserved.

  8. A novel high-heat transfer low-NO{sub x} natural gas combustion system. Phase 1 final report

    Energy Technology Data Exchange (ETDEWEB)

    Rue, D.M. [Institute of Gas Technology, Des Plaines, IL (United States); Fridman, A. [Univ. of Illinois, Chicago (United States); Viskanta, R. [Purdue Univ. (United States); Neff, D. [Cumbustion Tec, Inc. (United States)

    1997-11-01

    Phase I of the project focused on acquiring the market needs, modeling, design, and test plan information for a novel high-heat transfer low-NO{sub x} natural gas combustion system. All goals and objectives were achieved. The key component of the system is an innovative burner technology which combines high temperature natural gas preheating with soot formation and subsequent soot burnout in the flame, increases the system`s energy efficiency and furnace throughput, while minimizing the furnace air emissions, all without external parasitic systems. Work has included identifying industry`s needs and constraints, modeling the high luminosity burner system, designing the prototype burner for initial laboratory-scale testing, defining the test plan, adapting the burner technology to meet the industry`s needs and constraints, and outlining the Industrial Adoption Plan.

  9. GM's HCCI. In-vehicle experience with a future combustion system; GM's HCCI. Erfahrungen mit einem zukuenftigen Verbrennungssystem im Fahrzeugeinsatz

    Energy Technology Data Exchange (ETDEWEB)

    Pritze, Stefan; Koenigstein, Achim [Adam Opel GmbH, Ruesselsheim (Germany); Rayl, Allen; Chang, Chen-Fang; Najt, Paul; Grebe, Uwe D. [General Motors LLC, Warren/Ponitac, MI (United States)

    2010-07-01

    Homogeneous Charge Compression Ignition (HCCI) stands at General Motors (GM) for the auto-ignition of a homogeneous air-fuel mixture in a gasoline engine. HCCI enables unthrottle operation under part load conditions with the high potential for fuel consumption reduction at lowest NO{sub x} emission levels even with lean mixtures. It is capable to use worldwide available fuel qualities with conventional exhaust aftertreatment. Important requirements for the application in a vehicle are the realization of a large usable steady state map covering lowest engine loads including idle operation and an outstanding transient combustion performance in terms of robustness and responsiveness. The prerequisites to achieve this were set based on a spray-guided gasoline direct injection with a strategy to control the residuals by trapping and recompressing them in the combustion chamber and sensing of individual cylinder pressure. The main characteristics of the combustion system will be discussed. The application in a vehicle sets new targets in terms of engine controller requirements and the complexity of the control algorithms. Considering only indirect control of combustion being very sensitive against extraneous impacts, it becomes extremely challenging to realize robust transitions among the various operation modes. The results achieved with the integration of the presented HCCI combustion system in prototype vehicles of the midsize segment support the chosen development path. Further improvements can be expected considering the latest achievements of the combustion system development. (orig.)

  10. Injection system used into SI engines for complete combustion and reduction of exhaust emissions in the case of alcohol and petrol alcohol mixtures feed

    Science.gov (United States)

    Ispas, N.; Cofaru, C.; Aleonte, M.

    2017-10-01

    Internal combustion engines still play a major role in today transportation but increasing the fuel efficiency and decreasing chemical emissions remain a great goal of the researchers. Direct injection and air assisted injection system can improve combustion and can reduce the concentration of the exhaust gas pollutes. Advanced air-to-fuel and combustion air-to-fuel injection system for mixtures, derivatives and alcohol gasoline blends represent a major asset in reducing pollutant emissions and controlling combustion processes in spark-ignition engines. The use of these biofuel and biofuel blending systems for gasoline results in better control of spark ignition engine processes, making combustion as complete as possible, as well as lower levels of concentrations of pollutants in exhaust gases. The main purpose of this paper was to provide most suitable tools for ensure the proven increase in the efficiency of spark ignition engines, making them more environmentally friendly. The conclusions of the paper allow to highlight the paths leading to a better use of alcohols (biofuels) in internal combustion engines of modern transport units.

  11. Combustion Property Analysis and Control System for the Dynamics of a Single Cylinder Diesel Engine

    Directory of Open Access Journals (Sweden)

    Bambang Wahono

    2013-12-01

    Full Text Available Corresponding to global environment problems in recent year, the technology for reducing fuel consumption and exhaust gas emission of engine was needed. Simulation of transient engine response is needed to predict engine performance that frequently experience rapid changes of speed. The aim of this research is to develop a non-linear dynamic control model for direct injection single cylinder diesel engine which can simulate engine performance under transient conditions. In this paper, the combustion model with multistage injection and conducted experiments in the transient conditions to clarify the combustion characteristics was proposed. In order to perform the analysis of acceleration operation characteristics, it was built a Model Predictive Control (MPC to reproduce the characteristic values of the exhaust gas and fuel consumption from the control parameters in particular. Finally, MPC is an effective method to perform the analysis of characteristic in diesel engine under transient conditions.

  12. Transformations of inorganic coal constituents in combustion systems. Volume 1, sections 1--5: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Helble, J.J. [ed.; Srinivasachar, S.; Wilemski, G.; Boni, A.A. [PSI Technology Co., Andover, MA (United States); Kang, Shin-Gyoo; Sarofim, A.F.; Graham, K.A.; Beer, J.M. [Massachusetts Inst. of Tech., Cambridge, MA (United States); Peterson, T.W.; Wendt, J.O.L.; Gallagher, N.B.; Bool, L. [Arizona Univ., Tucson, AZ (United States); Huggins, F.E.; Huffman, G.P.; Shah, N.; Shah, A. [Kentucky Univ., Lexington, KY (United States)

    1992-11-01

    The inorganic constituents or ash contained in pulverized coal significantly increase the environmental and economic costs of coal utilization. For example, ash particles produced during combustion may deposit on heat transfer surfaces, decreasing heat transfer rates and increasing maintenance costs. The minimization of particulate emissions often requires the installation of cleanup devices such as electrostatic precipitators, also adding to the expense of coal utilization. Despite these costly problems, a comprehensive assessment of the ash formation and had never been attempted. At the start of this program, it was hypothesized that ash deposition and ash particle emissions both depended upon the size and chemical composition of individual ash particles. Questions such as: What determines the size of individual ash particles? What determines their composition? Whether or not particles deposit? How combustion conditions, including reactor size, affect these processes? remained to be answered. In this 6-year multidisciplinary study, these issues were addressed in detail. The ambitious overall goal was the development of a comprehensive model to predict the size and chemical composition distributions of ash produced during pulverized coal combustion. Results are described.

  13. Pressurized Fluidized Bed Combustion Second-Generation System Research and Development

    Energy Technology Data Exchange (ETDEWEB)

    A. Robertson; D. Horazak; R. Newby; H. Goldstein

    2002-11-01

    Research is being conducted under United States Department of Energy (DOE) Contract DE-AC21-86MC21023 to develop a new type of coal-fired plant for electric power generation. This new type of plant--called a Second-Generation or Advanced Pressurized Circulating Fluidized Bed Combustion (APCFB) plant--offers the promise of efficiencies greater than 45% (HHV), with both emissions and a cost of electricity that are significantly lower than conventional pulverized-coal-fired plants with scrubbers. The APCFB plant incorporates the partial gasification of coal in a carbonizer, the combustion of carbonizer char in a pressurized circulating fluidized bed boiler (PCFB), and the combustion of carbonizer syngas in a topping combustor to achieve gas turbine inlet temperatures of 2300 F and higher. A conceptual design was previously prepared for this new type of plant and an economic analysis presented, all based on the use of a Siemens Westinghouse W501F gas turbine with projected carbonizer, PCFB, and topping combustor performance data. Having tested these components at the pilot plant stage, the referenced conceptual design is being updated to reflect more accurate performance predictions together with the use of the more advanced Siemens Westinghouse W501G gas turbine and a conventional 2400 psig/1050 F/1050 F/2-1/2 in. steam turbine. This report describes the updated plant which is projected to have an HHV efficiency of 48% and identifies work completed for the October 2001 through September 2002 time period.

  14. Promotion of Ca-Co Bifunctional Catalyst/Sorbent with Yttrium for Hydrogen Production in Modified Chemical Looping Steam Methane Reforming Process

    Directory of Open Access Journals (Sweden)

    Samira Akbari-Emadabadi

    2017-09-01

    Full Text Available In this study, the application of a calcium-based bifunctional catalyst/sorbent is investigated in modified chemical looping steam methane reforming (CLSMR process for in situ CO2 sorption and H2 production. The yttrium promoted Ca-Co samples were synthesized and applied as bifunctional catalysts/sorbent. The influence of reduction temperature (500–750 °C, Ca/Co and Ca/Y ratios (1.5–∞ and 3–18, respectively and catalyst life time are determined in CLSMR process. The physicochemical transformation of fresh, used and regenerated samples after 16 redox cycles are determined using X-ray powder diffraction (XRD, N2 adsorption–desorption, field emission scanning electron microscopy (FESEM, energy dispersive X-ray spectroscopy (EDX and transmission electron microscopy (TEM techniques. The effect of yttrium promoter on the structure of catalyst and regeneration step on the reversibility of bifunctional catalyst/sorbent was two important factors. The characterization results revealed that the presence of yttrium in the structure of Ca-9Co sample could improve the morphology and textural properties of catalyst/sorbents. The suitable reversibility of bifunctional catalyst/sorbents during the repeated cycles is confirmed by characterization of calcined samples. The Ca-9Co-4.5Y as optimal catalyst illustrated superior performance and stability. It showed about 95.8% methane conversion and 82.9% hydrogen yield at 700 °C and stable activity during 16 redox cycles.

  15. Coal-fired combustion system for industrial process heating applications. Quarterly technical progress report, April 1995--June 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    PETC has implemented a number of advanced combustion research projects that will lead to the establishment of a broad, commercially acceptable engineering data base for the advancement of coal as the fuel of choice for boilers, furnaces, and process heaters. This includes new installations and those existing installations that were originally designed for oil or gas firing. The data generated by these projects must be sufficient for private-sector decisions on the feasibility of using coal as the fuel of choice. This work should also provide incentives for the private sector to continue and expand the development, demonstration, and application of these combustion systems. Vortec Corporation`s Coal-Fired Combustion System for Industrial Process Heating Applications is being developed under contract DE-AC22-91PC91161 as part of this DOE development program. The current contract represents the third phase of a three-phase development program. Phase I of the program addressed the technical and economic feasibility of the process, and was initiated in 1987 and completed 1989. Phase II was initiated in 1989 and completed in 1990. During Phase II of the development, design improvements were made to critical components and the test program addressed the performance of the process using several different feedstocks. Phase III of the program was initiated September 1991 and is scheduled for completion in 1994. The Phase III research effort is being focused on the development of a process heater system to be used for producing value-added vitrified glass products from boiler/incinerator ashes and selected industrial wastes.

  16. The Diesel Combustion Collaboratory: Combustion Researchers Collaborating over the Internet

    Energy Technology Data Exchange (ETDEWEB)

    C. M. Pancerella; L. A. Rahn; C. Yang

    2000-02-01

    The Diesel Combustion Collaborator (DCC) is a pilot project to develop and deploy collaborative technologies to combustion researchers distributed throughout the DOE national laboratories, academia, and industry. The result is a problem-solving environment for combustion research. Researchers collaborate over the Internet using DCC tools, which include: a distributed execution management system for running combustion models on widely distributed computers, including supercomputers; web-accessible data archiving capabilities for sharing graphical experimental or modeling data; electronic notebooks and shared workspaces for facilitating collaboration; visualization of combustion data; and video-conferencing and data-conferencing among researchers at remote sites. Security is a key aspect of the collaborative tools. In many cases, the authors have integrated these tools to allow data, including large combustion data sets, to flow seamlessly, for example, from modeling tools to data archives. In this paper the authors describe the work of a larger collaborative effort to design, implement and deploy the DCC.

  17. Development of flameless combustion; Desarrollo de la combustion sin flama

    Energy Technology Data Exchange (ETDEWEB)

    Flores Sauceda, M. Leonardo; Cervantes de Gortari, Jaime Gonzalo [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)]. E-mail: 8344afc@prodigy.net.mx; jgonzalo@servidor.unam.mx

    2010-11-15

    The paper intends contribute to global warming mitigation joint effort that develops technologies to capture the CO{sub 2} produced by fossil fuels combustion and to reduce emission of other greenhouse gases like the NO{sub x}. After reviewing existing combustion bibliography is pointed out that (a) touches only partial aspects of the collective system composed by Combustion-Heat transfer process-Environment, whose interactions are our primary interest and (b) most specialists think there is not yet a clearly winning technology for CO{sub 2} capture and storage. In this paper the study of combustion is focused as integrated in the aforementioned collective system where application of flameless combustion, using oxidant preheated in heat regenerators and fluent gas recirculation into combustion chamber plus appropriated heat and mass balances, simultaneously results in energy saving and environmental impact reduction. [Spanish] El trabajo pretende contribuir al esfuerzo conjunto de mitigacion del calentamiento global que aporta tecnologias para capturar el CO{sub 2} producido por la combustion de combustibles fosiles y para disminuir la emision de otros gases invernadero como NOx. De revision bibliografica sobre combustion se concluye que (a) trata aspectos parciales del sistema compuesto por combustion-proceso de trasferencia de calor-ambiente, cuyas interacciones son nuestro principal interes (b) la mayoria de especialistas considera no hay todavia una tecnologia claramente superior a las demas para captura y almacenaje de CO{sub 2}. Se estudia la combustion como parte integrante del mencionado sistema conjunto, donde la aplicacion de combustion sin flama, empleando oxidante precalentado mediante regeneradores de calor y recirculacion de gases efluentes ademas de los balances de masa y energia adecuados, permite tener simultaneamente ahorros energeticos e impacto ambiental reducido.

  18. Apparatus and filtering systems relating to combustors in combustion turbine engines

    Science.gov (United States)

    Johnson, Thomas Edward [Greer, SC; Zuo, Baifang [Simpsonville, SC; Stevenson, Christian Xavier [Inman, SC

    2012-07-24

    A combustor for a combustion turbine engine, the combustor that includes: a chamber defined by an outer wall and forming a channel between windows defined through the outer wall toward a forward end of the chamber and at least one fuel injector positioned toward an aft end of the chamber; a screen; and a standoff comprising a raised area on an outer surface of the outer wall near the periphery of the windows; wherein the screen extends over the windows and is supported by the standoff in a raised position in relation to the outer surface of the outer wall and the windows.

  19. Literature review of arc/plasma, combustion, and joule-heated melter vitrification systems

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, C.J.; Abrigo, G.P.; Shafer, P.J.; Merrill, R.A.

    1995-07-01

    This report provides reviews of papers and reports for three basic categories of melters: arc/plasma-heated melters, combustion-heated melters, and joule-heated melters. The literature reviewed here represents those publications which may lend insight to phase I testing of low-level waste vitrification being performed at the Hanford Site in FY 1995. For each melter category, information from those papers and reports containing enough information to determine steady-state mass balance data is tabulated at the end of each section. The tables show the composition of the feed processed, the off-gas measured via decontamination factors, gross energy consumptions, and processing rates, among other data.

  20. Transformations of inorganic coal constituents in combustion systems. Volume 3, Appendices: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Helble, J.J. [ed.; Srinivasachar, S.; Wilemski, G.; Boni, A.A. [PSI Technology Co., Andover, MA (United States); Kang, Shim-Gyoo; Sarofim, A.F.; Graham, K.A.; Beer, J.M. [Massachusetts Inst. of Tech., Cambridge, MA (United States); Peterson, T.W.; Wendt, O.L.; Gallagher, N.B.; Bool, L. [Arizona Univ., Tucson, AZ (United States); Huggins, F.E.; Huffman, G.P.; Shah, N.; Shah, A. [Kentucky Univ., Lexington, KY (United States)

    1992-11-01

    This report contains the computer codes developed for the coal combustion project. In Subsection B.1 the FORTRAN code developed for the percolative fragmentation model (or the discrete model, since a char is expressed as a collection of discrete elements in a discrete space) is presented. In Subsection B.2 the code for the continuum model (thus named because mineral inclusions are distributed in a continuum space) is presented. A stereological model code developed to obtain the pore size distribution from a two-dimensional data is presented in Subsection B.3.

  1. Univalve. A fully variable mechanical valve lift system for future internal combustion engines; Univalve. Ein vollvariables mechanisches Ventiltriebsystem fuer zukuenftige Verbrennungsmotoren

    Energy Technology Data Exchange (ETDEWEB)

    Flierl, Rudolf; Schmitt, Stephan [TU Kaiserslautern (Germany). Lehrstuhl fuer Verbrennungskraftmaschinen; Kleinert, Gerd; Esch, Hans-Joachim; Dismon, Heinrich [Kolbenschmidt Pierburg AG, Neckarsulm (Germany)

    2011-05-15

    In order to optimize the gas exchange and combustion sequences, the performance, emissions, and - above all else - the degree of effectiveness of internal combustion engines have to be fully utilized. The only way to achieve this potential is by using a valve train which enables infinitely variable adjustment of the inlet valve lift duration, thus permitting throttle-free load control. Therefore, the Kolbenschmidt Pierburg AG selected the Univalve system, developed by Entec Consulting GmbH, and recently acquired the rights to the new system. In joint effort, the Univalve system is now undergoing final development prior to full-scale serial production. (orig.)

  2. Homogeneous and Heterogeneous Reaction and Transformation of Hg and Trace Metals in Combustion Systems

    Energy Technology Data Exchange (ETDEWEB)

    J. Helble; Clara Smith; David Miller

    2009-08-31

    The overall goal of this project was to produce a working dynamic model to predict the transformation and partitioning of trace metals resulting from combustion of a broad range of fuels. The information provided from this model will be instrumental in efforts to identify fuels and conditions that can be varied to reduce metal emissions. Through the course of this project, it was determined that mercury (Hg) and arsenic (As) would be the focus of the experimental investigation. Experiments were therefore conducted to examine homogeneous and heterogeneous mercury oxidation pathways, and to assess potential interactions between arsenic and calcium. As described in this report, results indicated that the role of SO{sub 2} on Hg oxidation was complex and depended upon overall gas phase chemistry, that iron oxide (hematite) particles contributed directly to heterogeneous Hg oxidation, and that As-Ca interactions occurred through both gas-solid and within-char reaction pathways. Modeling based on this study indicated that, depending upon coal type and fly ash particle size, vaporization-condensation, vaporization-surface reaction, and As-CaO in-char reaction all play a role in arsenic transformations under combustion conditions.

  3. Nonlinear Combustion Instability Prediction

    Science.gov (United States)

    Flandro, Gary

    2010-01-01

    The liquid rocket engine stability prediction software (LCI) predicts combustion stability of systems using LOX-LH2 propellants. Both longitudinal and transverse mode stability characteristics are calculated. This software has the unique feature of being able to predict system limit amplitude.

  4. Synthesis and Application of Cerium-Incorporated SBA-16 Supported Ni-Based Oxygen Carrier in Cyclic Chemical Looping Steam Methane Reforming

    Directory of Open Access Journals (Sweden)

    Maryam Meshksar

    2018-01-01

    Full Text Available Hydrogen, as a clean energy carrier, could be produced aided by cyclic oxidation-reduction of oxygen carriers (OCs in contact with carbonaceous fuel in chemical looping steam methane reforming (CL-SMR process. In this study, the cerium was incorporated into the SBA-16 support structure to synthesize the Ni/Ce-SBA-16 OC. The supports were synthesized using hydrothermal method followed by impregnation of Ni and characterized via low and wide angle X-ray diffraction (XRD, Brunauer-Emmett-Teller (BET, scanning electron microscopy (SEM, coupled with energy dispersive X-ray (EDX spectroscopy, and transmission electron micrograph (TEM techniques. In addition, the effect of various Si/Ce molar ratios (20–60 in the support structure, Ni loading (10–30 wt %, reaction temperature (500–750 °C, and life time of optimal oxygen carrier over 16 cycles were investigated. The results of wide angle XRD and SEM revealed that the incorporation of CeO2 in the channels of SBA-16 caused the formation of nickel metallic particles with smaller size and prevents the coke formation. The results showed that OC with 15 wt % Ni and Si/Ce molar ratio of 40 (15Ni/Ce-SBA-16(40 has the best performance when compared with other OCs in terms of catalytic activity and structural properties. The methane conversion of about 99.7% was achieved at 700 °C using 15Ni/Ce-SBA-16(40 OC. We anticipate that the strategy can be extended to investigate a variety of novel modified mesoporous silica as the supporting material for the Ni based OCs.

  5. Experimental findings on thermal use of residues and biofuels in circulating fluidized bed combustion systems; Experimentelle Ergebnisse zur thermischen Nutzung von Rest- und Biobrennstoffen in zirkulierenden Wirbelschichtfeuerungen

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, W.; Brunne, T.; Girndt, H. [Technische Univ. Dresden (Germany); Albrecht, J. [Lurgi Lentjes Babcock, Frankfurt am Main (Germany); Youssef, M. [Minia Univ. (Egypt)

    1996-12-31

    The energy Engineering Institute of Dresden Technical University investigated the combustion and emission characteristics of a number of combustion systems, including a circulating fluidized bed system with a capacity of 0.3 MW{sub th}. Egypt`s sugar cane industry produces large volumes of bagasse. The conbustion and emission characteristics of this biofuel in a circulating fludized bed combustion systems were investigated in a joint research project of the University of Minia and Dresden Technical University. (orig.) [Deutsch] Am Institut fuer Energietechnik der TU Dresden wird das Verbrennungs- und Emissionsverhalten verschiedenster Brennstoffe in unterschiedlichen Feuerungssystemen untersucht. Neben anderen Pilotanlagen steht eine zirkulierende Wirbelschichtfeuerung (ZWFS) mit einer Leistung von 0.3 MW{sub th} zur Verfuegung. In der Zuckerrohrindustrie Aegyptens fallen grosse Mengen von Bagasse an. In einer gemeinsamen Forschungsarbeit zwischen der Universitaet Minia und der TU Dresden sollte das Verbrennungs- und Emissionsverhalten dieses Biobrennstoffes in einer ZWSF untersucht werden. (orig)

  6. Reducing NOx Emissions for a 600 MWe Down-Fired Pulverized-Coal Utility Boiler by Applying a Novel Combustion System.

    Science.gov (United States)

    Ma, Lun; Fang, Qingyan; Lv, Dangzhen; Zhang, Cheng; Chen, Yiping; Chen, Gang; Duan, Xuenong; Wang, Xihuan

    2015-11-03

    A novel combustion system was applied to a 600 MWe Foster Wheeler (FW) down-fired pulverized-coal utility boiler to solve high NOx emissions, without causing an obvious increase in the carbon content of fly ash. The unit included moving fuel-lean nozzles from the arches to the front/rear walls and rearranging staged air as well as introducing separated overfire air (SOFA). Numerical simulations were carried out under the original and novel combustion systems to evaluate the performance of combustion and NOx emissions in the furnace. The simulated results were found to be in good agreement with the in situ measurements. The novel combustion system enlarged the recirculation zones below the arches, thereby strengthening the combustion stability considerably. The coal/air downward penetration depth was markedly extended, and the pulverized-coal travel path in the lower furnace significantly increased, which contributed to the burnout degree. The introduction of SOFA resulted in a low-oxygen and strong-reducing atmosphere in the lower furnace region to reduce NOx emissions evidently. The industrial measurements showed that NOx emissions at full load decreased significantly by 50%, from 1501 mg/m3 (O2 at 6%) to 751 mg/m3 (O2 at 6%). The carbon content in the fly ash increased only slightly, from 4.13 to 4.30%.

  7. Bubble Combustion

    Science.gov (United States)

    Corrigan, Jackie

    2004-01-01

    A method of energy production that is capable of low pollutant emissions is fundamental to one of the four pillars of NASA s Aeronautics Blueprint: Revolutionary Vehicles. Bubble combustion, a new engine technology currently being developed at Glenn Research Center promises to provide low emissions combustion in support of NASA s vision under the Emissions Element because it generates power, while minimizing the production of carbon dioxide (CO2) and nitrous oxides (NOx), both known to be Greenhouse gases. and allows the use of alternative fuels such as corn oil, low-grade fuels, and even used motor oil. Bubble combustion is analogous to the inverse of spray combustion: the difference between bubble and spray combustion is that spray combustion is spraying a liquid in to a gas to form droplets, whereas bubble combustion involves injecting a gas into a liquid to form gaseous bubbles. In bubble combustion, the process for the ignition of the bubbles takes place on a time scale of less than a nanosecond and begins with acoustic waves perturbing each bubble. This perturbation causes the local pressure to drop below the vapor pressure of the liquid thus producing cavitation in which the bubble diameter grows, and upon reversal of the oscillating pressure field, the bubble then collapses rapidly with the aid of the high surface tension forces acting on the wall of the bubble. The rapid and violent collapse causes the temperatures inside the bubbles to soar as a result of adiabatic heating. As the temperatures rise, the gaseous contents of the bubble ignite with the bubble itself serving as its own combustion chamber. After ignition, this is the time in the bubble s life cycle where power is generated, and CO2, and NOx among other species, are produced. However, the pollutants CO2 and NOx are absorbed into the surrounding liquid. The importance of bubble combustion is that it generates power using a simple and compact device. We conducted a parametric study using CAVCHEM

  8. Biofuels combustion.

    Science.gov (United States)

    Westbrook, Charles K

    2013-01-01

    This review describes major features of current research in renewable fuels derived from plants and from fatty acids. Recent and ongoing fundamental studies of biofuel molecular structure, oxidation reactions, and biofuel chemical properties are reviewed, in addition to combustion applications of biofuels in the major types of engines in which biofuels are used. Biofuels and their combustion are compared with combustion features of conventional petroleum-based fuels. Two main classes of biofuels are described, those consisting of small, primarily alcohol, fuels (particularly ethanol, n-butanol, and iso-pentanol) that are used primarily to replace or supplement gasoline and those derived from fatty acids and used primarily to replace or supplement conventional diesel fuels. Research efforts on so-called second- and third-generation biofuels are discussed briefly.

  9. Particulate and gaseous emissions from different wood fuels during combustion in a small-scale biomass heating system

    Science.gov (United States)

    Olave, R. J.; Forbes, E. G. A.; Johnston, C. R.; Relf, J.

    2017-05-01

    Woodchip is widely used as fuel in dedicated biomass and, even in some conventional energy generation plants. However, there are concerns about atmospheric air pollution from flue gases emitted during wood biomass combustion, particularly oxides of nitrogen (NOx) and particulates Renewable Heat Incentive (RHI), has been introduced. Qualifying criteria for this scheme have included limits for flue gas emissions of NOX and PM10 of 150 and 30 g per gigajoule (g/GJ) of energy input, respectively. In an experiment, three locally available types of Willow (Salix spp) and one of Sitka spruce (Picea sitchensis) woodchips, showed significant differences in physical and chemical constituents, gaseous and particulate emissions. During combustion in a 120 kW biomass system, air flows, flue gas temperatures and energy output correlated with gaseous emissions, NOx with raw fuel ash, nitrogen, phosphorus and potassium content, as did all flue gas particulate fractions. PM10 ranged from 30.3 to 105.7 g/GJ and NOx from 91.2 to 174.3 g/GJ. Sitka spruce produced significantly lower emissions of PM10 and NOx (27.5 and 52.6% less, respectively) than the three willow fuels, from which emissions were above the RHI emissions limits.

  10. Application of urea based SNCR system in the combustion effluent containing low level of baseline nitric oxide.

    Science.gov (United States)

    Hossain, K A; Mohd-Jaafar, M N; Appalanidu, K B; Mustafa, A; Ani, F N

    2005-03-01

    Selective Non-Catalytic Reduction (SNCR) of nitric oxide has been studied experimentally by injecting aqueous urea solution with and without additive in a pilot-scale diesel fired tunnel furnace at 3.4% excess oxygen level and with low ppm of baseline NO(x) ranging from 65 to 75 ppm within the investigated temperature range. The tests have been carried out using commercial grade urea as NO(x) reducing agent and commercial grade sodium carbonate as additive. The furnace simulated the small-scale combustion systems, where the operating temperatures are usually in the range of about 973 to 1323 K and NO(x) emission level remains below 100 ppm. With 5% plain urea solution, at Normalized Stoichiometric Ratio (NSR) of 4 as much as 54% reduction was achieved at 1128 K, whilst in the additive case the NO(x) reduction was improved to as much as 69% at 1093 K. Apart from this improvement, in the additive case, the effective temperature window as well as peak temperature of NO(x) reduction shifted towards lower temperatures. The result is quite significant, especially for this investigated level of baseline NO(x). The ammonia slip measurements showed that in both cases the slip was below 16 ppm at NSR of 4 and optimum temperature of NO(x) reduction. Finally, the investigations demonstrated that urea based SNCR is quite applicable to small-scale combustion applications and commercial grade sodium carbonate is a potential additive.

  11. New, efficient and viable system for ethanol fuel utilization on combined electric/internal combustion engine vehicles

    Science.gov (United States)

    Sato, André G.; Silva, Gabriel C. D.; Paganin, Valdecir A.; Biancolli, Ana L. G.; Ticianelli, Edson A.

    2015-10-01

    Although ethanol can be directly employed as fuel on polymer-electrolyte fuel cells (PEMFC), its low oxidation kinetics in the anode and the crossover to the cathode lead to a substantial reduction of energy conversion efficiency. However, when fuel cell driven vehicles are considered, the system may include an on board steam reformer for converting ethanol into hydrogen, but the hydrogen produced contains carbon monoxide, which limits applications in PEMFCs. Here, we present a system consisting of an ethanol dehydrogenation catalytic reactor for producing hydrogen, which is supplied to a PEMFC to generate electricity for electric motors. A liquid by-product effluent from the reactor can be used as fuel for an integrated internal combustion engine, or catalytically recycled to extract more hydrogen molecules. Power densities comparable to those of a PEMFC operating with pure hydrogen are attained by using the hydrogen rich stream produced by the ethanol dehydrogenation reactor.

  12. System Study of Rich Catalytic/Lean burn (RCL) Catalytic Combustion for Natural Gas and Coal-Derived Syngas Combustion Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Shahrokh Etemad; Lance Smith; Kevin Burns

    2004-12-01

    Rich Catalytic/Lean burn (RCL{reg_sign}) technology has been successfully developed to provide improvement in Dry Low Emission gas turbine technology for coal derived syngas and natural gas delivering near zero NOx emissions, improved efficiency, extending component lifetime and the ability to have fuel flexibility. The present report shows substantial net cost saving using RCL{reg_sign} technology as compared to other technologies both for new and retrofit applications, thus eliminating the need for Selective Catalytic Reduction (SCR) in combined or simple cycle for Integrated Gasification Combined Cycle (IGCC) and natural gas fired combustion turbines.

  13. Combustion 2000

    Energy Technology Data Exchange (ETDEWEB)

    A. Levasseur; S. Goodstine; J. Ruby; M. Nawaz; C. Senior; F. Robson; S. Lehman; W. Blecher; W. Fugard; A. Rao; A. Sarofim; P. Smith; D. Pershing; E. Eddings; M. Cremer; J. Hurley; G. Weber; M. Jones; M. Collings; D. Hajicek; A. Henderson; P. Klevan; D. Seery; B. Knight; R. Lessard; J. Sangiovanni; A. Dennis; C. Bird; W. Sutton; N. Bornstein; F. Cogswell; C. Randino; S. Gale; Mike Heap

    2001-06-30

    . To achieve these objectives requires a change from complete reliance of coal-fired systems on steam turbines (Rankine cycles) and moving forward to a combined cycle utilizing gas turbines (Brayton cycles) which offer the possibility of significantly greater efficiency. This is because gas turbine cycles operate at temperatures well beyond current steam cycles, allowing the working fluid (air) temperature to more closely approach that of the major energy source, the combustion of coal. In fact, a good figure of merit for a HIPPS design is just how much of the enthalpy from coal combustion is used by the gas turbine. The efficiency of a power cycle varies directly with the temperature of the working fluid and for contemporary gas turbines the optimal turbine inlet temperature is in the range of 2300-2500 F (1260-1371 C). These temperatures are beyond the working range of currently available alloys and are also in the range of the ash fusion temperature of most coals. These two sets of physical properties combine to produce the major engineering challenges for a HIPPS design. The UTRC team developed a design hierarchy to impose more rigor in our approach. Once the size of the plant had been determined by the choice of gas turbine and the matching steam turbine, the design process of the High Temperature Advanced Furnace (HITAF) moved ineluctably to a down-fired, slagging configuration. This design was based on two air heaters: one a high temperature slagging Radiative Air Heater (RAH) and a lower temperature, dry ash Convective Air Heater (CAH). The specific details of the air heaters are arrived at by an iterative sequence in the following order:-Starting from the overall Cycle requirements which set the limits for the combustion and heat transfer analysis-The available enthalpy determined the range of materials, ceramics or alloys, which could tolerate the temperatures-Structural Analysis of the designs proved to be the major limitation-Finally the commercialization

  14. DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS FIRED COMBUSTION SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Glenn England; Oliver Chang; Stephanie Wien

    2002-02-14

    This report provides results from the second year of this three-year project to develop dilution measurement technology for characterizing PM2.5 (particles with aerodynamic diameter smaller than 2.5 micrometers) and precursor emissions from stationary combustion sources used in oil, gas and power generation operation. Detailed emission rate and chemical speciation tests results for a gas turbine, a process heater, and a commercial oil/gas fired boiler are presented. Tests were performed using a research dilution sampling apparatus and traditional EPA methods. A series of pilot tests were conducted to identify the constraints to reduce the size of current research dilution sampler for future stack emission tests. Based on the test results, a bench prototype compact dilution sampler developed and characterized in GE EER in August 2002.

  15. Start up system for hydrogen generator used with an internal combustion engine

    Science.gov (United States)

    Houseman, J.; Cerini, D. J. (Inventor)

    1977-01-01

    A hydrogen generator provides hydrogen rich product gases which are mixed with the fuel being supplied to an internal combustion engine for the purpose of enabling a very lean mixture of that fuel to be used, whereby nitrous oxides emitted by the engine are minimized. The hydrogen generator contains a catalyst which must be heated to a pre-determined temperature before it can react properly. To simplify the process of heating up the catalyst at start-up time, either some of the energy produced by the engine such as engine exhaust gas, or electrical energy produced by the engine, or the engine exhaust gas may be used to heat up air which is then used to heat the catalyst.

  16. Furnaces with multiple ?ameless combustion burners

    NARCIS (Netherlands)

    Danon, B.

    2011-01-01

    In this thesis three different combustion systems, equipped with either a single or multiple ?ameless combustion burner(s), are discussed. All these setups were investigated both experimentally and numerically, i.e., using Computational Fluid Dynamics (CFD) simulations. Flameless combustion is a

  17. Strategy for intelligent internal combustion engine with homogenous combustion in cylinder

    OpenAIRE

    Weclas, Miroslaw

    2009-01-01

    In this report the author proposes strategy for development of intelligent combustion systems with a goal to approach a near-zero emission internal combustion engine operating in a wide range of speeds and loads. Main requirement for future I.C. engine is to develop a system permitting homogeneous combustion process (minimum of engine emissions) under all operational conditions. The author suggests, that none existing individual combustion system may satisfy these conditions. However, combina...

  18. Combustion synthesis in the Ni-Al-Nb ternary system: A Time-Resolved X-ray Diffraction study

    Science.gov (United States)

    Sytschev, Alexander E.; Kovalev, Dmitry Yu.; Vrel, Dominique; Vadchenko, Sergey G.

    Combustion synthesis of intermetallics, using the thermal explosion mode, in the Ni-Al-Nb ternary system is presented, with a 40:40:20 atomic ratio. The kinetic pathway is determined using Time-Resolved X-ray Diffraction, with a time-step resolution of 1 s and demonstrated a first formation of the B2 NiAl structure followed by progressive dissolution of Nb to yield NiAlNb intermetallic Laves phase, representing 35 w% of the final product. SEM observations show a double dendritic (coarse and fine) microstructure, resulting from eutectic crystallization. Due to a high cooling rate, Nb dissolution is not complete at the surface, and yields slightly more complex microstructure, including the Ni2AlNb Geissler phase, the (Ni,Al)2Nb Laves phase, and (Ni, Al)7Nb6.

  19. Combustion systems: a porous-matrix burner and a surface combustor. Topical report, June 1984-December 1985

    Energy Technology Data Exchange (ETDEWEB)

    Jasionowski, W.J.; Kunc, W.; Khinkis, M.J.; Zawacki, T.S.

    1987-12-01

    In this study, two combustion systems were experimentally evaluated for potential application to gas-fired appliances: an atmospheric porous-matrix burner and a packed-bed surface combustor. The normal radiant output of a porous matrix burner was measured over a range of input from 30,000 to 110,000 Btu/h-sq ft and aerations from 0% to 40% excess air. The data were compared to similar published data for radiant tile burners. Emissions of nitric oxide (NO), nitrogen dioxide (NO/sub 2/), and carbon monoxide (CO) were also measured and reported. The potential advantage of the type of burner is its ability to produce high levels of radiation heat at high gas-loading levels (Btu/h-sq ft.).

  20. Materials problems in fluidized-bed combustion systems. Appendix 2. Test specimen preparation, handling, and posttest evaluation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, E.A.; Holder, J.C.; Minchener, A.J.; Page, A.J.; La Nauze, R.D.

    1980-05-01

    Appendix 2 presents the metallographic data compiled by the National Coal Board, Coal Research Establishment, on materials tested for the Electric Power Research Institute Contract R P 388-1 with Combustion Systems Ltd., UK. Two 1000 h tests were carried out to investigate the corrosion performance of boiler and gas turbine alloys exposed in and above a fluidised bed coal combustor. Details are given of the preparation, handling, and examination procedures. Results of metallographic examination and chemical analyses on the samples examined by CRE are provided. This appendix does not attempt to draw any conclusions from the data: such conclusions appear in the main report. Description of the tests and plant performance data are given in Appendix 1 of this report.

  1. Supersonic Combustion Ramjet Research

    Science.gov (United States)

    2012-08-01

    engine). As noted above in USAF scramjet flight scenarios , high vehicle heat loads will ensure that the fuel (initially a liquid hydrocarbon such as a... cinema stereoscopic PIV system for the measurement of micro- and meso-scale turbulent premixed flame dynamics,” Paper B13, 5th US Combustion

  2. Pulsating combustion - Combustion characteristics and reduction of emissions

    Energy Technology Data Exchange (ETDEWEB)

    Lindholm, Annika

    1999-11-01

    In the search for high efficiency combustion systems pulsating combustion has been identified as one of the technologies that potentially can meet the objectives of clean combustion and good fuel economy. Pulsating combustion offers low emissions of pollutants, high heat transfer and efficient combustion. Although it is an old technology, the interest in pulsating combustion has been renewed in recent years, due to its unique features. Various applications of pulsating combustion can be found, mainly as drying and heating devices, of which the latter also have had commercial success. It is, however, in the design process of a pulse combustor, difficult to predict the operating frequency, the heat release etc., due to the lack of a well founded theory of the phenomenon. Research concerning control over the combustion process is essential for developing high efficiency pulse combustors with low emissions. Natural gas fired Helmholtz type pulse combustors have been the experimental objects of this study. In order to investigate the interaction between the fluid dynamics and the chemistry in pulse combustors, laser based measuring techniques as well as other conventional measuring techniques have been used. The experimental results shows the possibilities to control the combustion characteristics of pulsating combustion. It is shown that the time scales in the large vortices created at the inlet to the combustion chamber are very important for the operation of the pulse combustor. By increasing/decreasing the time scale for the large scale mixing the timing of the heat release is changed and the operating characteristics of the pulse combustor changes. Three different means for NO{sub x} reduction in Helmholtz type pulse combustors have been investigated. These include exhaust gas recirculation, alteration of air/fuel ratio and changed inlet geometry in the combustion chamber. All used methods achieved less than 10 ppm NO{sub x} emitted (referred to stoichiometric

  3. Fuel-Flexible Combustion System for Refinery and Chemical Plant Process Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Charles [Environ Holdings, Inc., Arlington, VA (United States); Wilson, Robert [Environ Holdings, Inc., Arlington, VA (United States)

    2014-07-15

    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

  4. Micro-Mixing Lean-Premix System for Ultra-Low Emission Hydrogen/Syngas Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Erlendur Steinthorsson; Brian Hollon; Adel Mansour

    2010-06-30

    The focus of this project was to develop the next generation of fuel injection technologies for environmentally friendly, hydrogen syngas combustion in gas turbine engines that satisfy DOE's objectives of reducing NOx emissions to 3 ppm. Building on Parker Hannifin's proven Macrolamination technology for liquid fuels, Parker developed a scalable high-performing multi-point injector that utilizes multiple, small mixing cups in place of a single conventional large-scale premixer. Due to the small size, fuel and air mix rapidly within the cups, providing a well-premixed fuel-air mixture at the cup exit in a short time. Detailed studies and experimentation with single-cup micro-mixing injectors were conducted to elucidate the effects of various injector design attributes and operating conditions on combustion efficiency, lean stability and emissions and strategies were developed to mitigate the impact of flashback. In the final phase of the program, a full-scale 1.3-MWth multi-cup injector was built and tested at pressures from 6.9bar (100psi) to 12.4bar (180psi) and flame temperatures up to 2000K (3150 F) using mixtures of hydrogen and natural gas as fuel with nitrogen and carbon dioxide as diluents. The injector operated without flash back on fuel mixtures ranging from 100% natural gas to 100% hydrogen and emissions were shown to be insensitive to combustor pressure. NOx emissions of 3-ppm were achieved at a flame temperature of 1750K (2690 F) when operating on a fuel mixture containing 50% hydrogen and 50% natural gas by volume with 40% nitrogen dilution and 1.5-ppm NOx was achieved at a flame temperature of 1680K (2564 F) using only 10% nitrogen dilution. NOx emissions of 3.5-ppm were demonstrated at a flame temperature of 1730K (2650 F) with only 10% carbon dioxide dilution. Finally, 3.6-ppm NOx emissions were demonstrated at a flame temperature over 1600K (2420 F) when operating on 100% hydrogen fuel with 30% carbon dioxide dilution. Superior

  5. Assessment of Solid Sorbent Systems for Post-Combustion Carbon Dioxide Capture at Coal-Fired Power Plants

    Science.gov (United States)

    Glier, Justin C.

    In an effort to lower future CO2 emissions, a wide range of technologies are being developed to scrub CO2 from the flue gases of fossil fuel-based electric power and industrial plants. This thesis models one of several early-stage post-combustion CO2 capture technologies, solid sorbent-based CO2 capture process, and presents performance and cost estimates of this system on pulverized coal power plants. The spreadsheet-based software package Microsoft Excel was used in conjunction with AspenPlus modelling results and the Integrated Environmental Control Model to develop performance and cost estimates for the solid sorbent-based CO2 capture technology. A reduced order model also was created to facilitate comparisons among multiple design scenarios. Assumptions about plant financing and utilization, as well as uncertainties in heat transfer and material design that affect heat exchanger and reactor design were found to produce a wide range of cost estimates for solid sorbent-based systems. With uncertainties included, costs for a supercritical power plant with solid sorbent-based CO2 capture ranged from 167 to 533 per megawatt hour for a first-of-a-kind installation (with all costs in constant 2011 US dollars) based on a 90% confidence interval. The median cost was 209/MWh. Post-combustion solid sorbent-based CO2 capture technology is then evaluated in terms of the potential cost for a mature system based on historic experience as technologies are improved with sequential iterations of the currently available system. The range costs for a supercritical power plant with solid sorbent-based CO2 capture was found to be 118 to 189 per megawatt hour with a nominal value of 163 per megawatt hour given the expected range of technological improvement in the capital and operating costs and efficiency of the power plant after 100 GW of cumulative worldwide experience. These results suggest that the solid sorbent-based system will not be competitive with currently available

  6. Tubular combustion

    CERN Document Server

    Ishizuka, Satoru

    2014-01-01

    Tubular combustors are cylindrical tubes where flame ignition and propagation occur in a spatially confined, highly controlled environment, in a nearly flat, elongated geometry. This allows for some unique advantages where extremely even heat dispersion is required over a large surface while still maintaining fuel efficiency. Tubular combustors also allow for easy flexibility in type of fuel source, allowing for quick changeover to meet various needs and changing fuel pricing. This new addition to the MP sustainable energy series will provide the most up-to-date research on tubular combustion--some of it only now coming out of private proprietary protection. Plentiful examples of current applications along with a good explanation of background theory will offer readers an invaluable guide on this promising energy technology. Highlights include: * An introduction to the theory of tubular flames * The "how to" of maintaining stability of tubular flames through continuous combustion * Examples of both small-scal...

  7. A Novel High-Heat Transfer Low-NO{sub x} Natural Gas Combustion System. Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Abbasi, H.

    2004-01-01

    A novel high-heat transfer low NO(sub x) natural gas combustion system. The objectives of this program are to research, develop, test, and commercialize a novel high-heat transfer low-NO{sub x} natural gas combustion system for oxygen-, oxygen-enriched air, and air-fired furnaces. This technology will improve the process efficiency (productivity and product quality) and the energy efficiency of high-temperature industrial furnaces by at least 20%. GTI's high-heat transfer burner has applications in high-temperature air, oxygen-enriched air, and oxygen furnaces used in the glass, metals, cement, and other industries. Development work in this program is focused on using this burner to improve the energy efficiency and productivity of glass melting furnaces that are major industrial energy consumers. The following specific project objectives are defined to provide a means of achieving the overall project objectives. (1) Identify topics to be covered, problems requiring attention, equipment to be used in the program, and test plans to be followed in Phase II and Phase III. (2) Use existing codes to develop models of gas combustion and soot nucleation and growth as well as a thermodynamic and parametric description of furnace heat transfer issues. (3) Conduct a parametric study to confirm the increase in process and energy efficiency. (4) Design and fabricate a high-heat transfer low-NOx natural gas burners for laboratory, pilot- and demonstration-scale tests. (5) Test the high-heat transfer burner in one of GTI's laboratory-scale high-temperature furnaces. (6) Design and demonstrate the high-heat transfer burner on GTI's unique pilot-scale glass tank simulator. (7) Complete one long term demonstration test of this burner technology on an Owens Corning full-scale industrial glass melting furnace. (8) Prepare an Industrial Adoption Plan. This Plan will be updated in each program Phase as additional information becomes available. The Plan will include

  8. Advanced Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Holcomb, Gordon R. [NETL

    2013-03-11

    The activity reported in this presentation is to provide the mechanical and physical property information needed to allow rational design, development and/or choice of alloys, manufacturing approaches, and environmental exposure and component life models to enable oxy-fuel combustion boilers to operate at Ultra-Supercritical (up to 650{degrees}C & between 22-30 MPa) and/or Advanced Ultra-Supercritical conditions (760{degrees}C & 35 MPa).

  9. Quantum Chemical Study of CH3 + O2 Combustion Reaction System: Catalytic Effects of Additional CO2 Molecule.

    Science.gov (United States)

    Masunov, Artëm E; Wait, Elizabeth; Vasu, Subith S

    2017-08-03

    The supercritical carbon dioxide diluent is used to control the temperature and to increase the efficiency in oxycombustion fossil fuel energy technology. It may affect the rates of combustion by altering mechanisms of chemical reactions, compared to the ones at low CO2 concentrations. Here, we investigate potential energy surfaces of the four elementary reactions in the CH3 + O2 reactive system in the presence of one CO2 molecule. In the case of reaction CH3 + O2 → CH2O + OH (R1 channel), van der Waals (vdW) complex formation stabilizes the transition state and reduces the activation barrier by ∼2.2 kcal/mol. Alternatively, covalently bonded CO2 may form a six-membered ring transition state and reduce the activation barrier by ∼0.6 kcal/mol. In case of reaction CH3 + O2 → CH3O + O (R2 channel), covalent participation of CO2 lowers the barrier for the rate limiting step by 3.9 kcal/mol. This is expected to accelerate the R2 process, important for the branching step of the radical chain reaction mechanism. For the reaction CH3 + O2 → CHO + H2O (R3 channel) with covalent participation of CO2, the activation barrier is lowered by 0.5 kcal/mol. The reaction CH2O + OH → CHO + H2O (R4 channel) involves hydrogen abstraction from formaldehyde by OH radical. Its barrier is reduced from 7.1 to 0.8 kcal/mol by formation of vdW complex with spectator CO2. These new findings are expected to improve the kinetic reaction mechanism describing combustion processes in supercritical CO2 medium.

  10. Thermal Stability, Combustion Behavior, and Mechanical Property in a Flame-Retardant Polypropylene System

    Directory of Open Access Journals (Sweden)

    Lili Wang

    2017-01-01

    Full Text Available In order to comprehensively improve the strength, toughness, flame retardancy, smoke suppression, and thermal stability of polypropylene (PP, layered double hydroxide (LDH Ni0.2Mg2.8Al–LDH was synthesized by a coprecipitation method coupled with the microwave-hydrothermal treatment. The X-ray diffraction (XRD, morphology, mechanical, thermal, and fire properties for PP composites containing 1 wt %–20 wt % Ni0.2Mg2.8Al–LDH were investigated. The cone calorimeter tests confirm that the peak heat release rate (pk–HRR of PP–20%LDH was decreased to 500 kW/m2 from the 1057 kW/m2 of PP. The pk–HRR, average mass loss rate (AMLR and effective heat of combustion (EHC analysis indicates that the condensed phase fire retardant mechanism of Ni0.2Mg2.8Al–LDH in the composites. The production rate and mean release yield of CO for composites gradually decrease as Ni0.2Mg2.8Al–LDH increases in the PP matrix. Thermal analysis indicates that the decomposition temperature for PP–5%LDH and PP–10%LDH is 34 °C higher than that of the pure PP. The mechanical tests reveal that the tensile strength of PP–1%LDH is 7.9 MPa higher than that of the pure PP. Furthermore, the elongation at break of PP–10%LDH is 361% higher than PP. In this work, the synthetic LDH Ni0.2Mg2.8Al–LDH can be used as a flame retardant, smoke suppressant, thermal stabilizer, reinforcing, and toughening agent of PP products.

  11. Systems Analysis of Technologies for Energy Recovery from Waste. Part I. Gasification followed by Catalytic Combustion, PEM Fuel Cells and Solid Oxide Fuel Cells for Stationary Applications in Comparison with Incineration. Part - II. Catalytic combustion - Experimental part

    Energy Technology Data Exchange (ETDEWEB)

    Assefa, Getachew; Frostell, Bjoern [Royal Inst. of Technology, Stockholm (Sweden). Div. of Industrial Ecology; Jaeraas, Sven; Kusar, Henrik [Royal Inst. of Technology, Stockholm (Sweden). Div. of Chemical Technology

    2005-02-01

    This project is entitled 'Systems Analysis: Energy Recovery from waste, catalytic combustion in comparison with fuel cells and incineration'. Some of the technologies that are currently developed by researchers at the Royal Institute of Technology include catalytic combustion and fuel cells as downstream units in a gasification system. The aim of this project is to assess the energy turnover as well as the potential environmental impacts of biomass/waste-to-energy technologies. In second part of this project economic analyses of the technologies in general and catalytic combustion and fuel cell technologies in particular will be carried out. Four technology scenarios are studied: (1) Gasification followed by Low temperature fuel cells (Proton Exchange Membrane (PEM) fuel cells) (2) Gasification followed by high temperature fuel cells (Solid Oxide Fuel Cells (SOFC) (3) Gasification followed by catalytic combustion and (4) Incineration with energy recovery. The waste used as feedstock is an industrial waste containing parts of household waste, paper waste, wood residues and poly ethene. In the study compensatory district heating is produced by combustion of biofuel. The power used for running the processes in the scenarios will be supplied by the waste-to-energy technologies themselves while compensatory power is assumed to be produced from natural gas. The emissions from the system studied are classified and characterised using methodology from Life Cycle Assessment in to the following environmental impact categories: Global Warming Potential, Acidification Potential, Eutrophication Potential and finally Formation of Photochemical Oxidants. Looking at the result of the four technology chains in terms of the four impact categories with impact per GWh electricity produced as a unit of comparison and from the perspective of the rank each scenario has in all the four impact categories, SOFC appears to be the winner technology followed by PEM and CC as second

  12. Prospects for using a full-scale installation for wet combustion of organic wastes in closed life support systems.

    Science.gov (United States)

    Trifonov, Sergey V; Kudenko, Yurii A; Tikhomirov, Alexander A

    2015-11-01

    The issue of recycling organic wastes in closed life support systems (CLSS) includes both fundamental aspects of environmental safety of the recycled products and their effective involvement in material cycles and technical aspects related to the structure of the system and the crew's demands. This study estimates the effectiveness of wet combustion of different amounts of organic wastes in hydrogen peroxide under application of an alternating current electric field. The study also addresses the possibility of controlling the process automatically. The results show that processing of greater amounts of wastes reduces specific power consumption and shortens the duration of the process, without significantly affecting the level of oxidation of the products. An automatic control system for a semi-commercial installation has been constructed and tested experimentally. The solution of mineralized human wastes prepared in the automatically controlled process in this installation was successfully used to grow radish plants, with the main production parameters being similar to those of the control. Copyright © 2015 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

  13. Fluid-bed combustion

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, G.; Schoebotham, N.

    1981-02-01

    In Energy Equipment Company's two-stage fluidized bed system, partial combustion in a fluidized bed is followed by burn-off of the generated gases above the bed. The system can be retrofitted to existing boilers, and can burn small, high ash coal efficiently. It has advantages when used as a hot gas generator for process drying. Tests on a boiler at a Cadbury Schweppes plant are reported.

  14. Combustion science and engineering

    CERN Document Server

    Annamalai, Kalyan

    2006-01-01

    Introduction and Review of Thermodynamics Introduction Combustion Terminology Matter and Its Properties Microscopic Overview of Thermodynamics Conservation of Mass and Energy and the First Law of Thermodynamics The Second Law of Thermodynamics Summary Stoichiometry and Thermochemistry of Reacting Systems Introduction Overall Reactions Gas Analyses Global Conservation Equations for Reacting Systems Thermochemistry Summary Appendix Reaction Direction and Equilibrium Introduction Reaction Direction and Chemical Equilibrium Chemical Equilibrium Relations Vant Hoff Equation Adi

  15. Sensitivity analysis of large system of chemical kinetic parameters for engine combustion simulation

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, H; Sanz-Argent, J; Petitpas, G; Havstad, M; Flowers, D

    2012-04-19

    In this study, the authors applied the state-of-the art sensitivity methods to downselect system parameters from 4000+ to 8, (23000+ -> 4000+ -> 84 -> 8). This analysis procedure paves the way for future works: (1) calibrate the system response using existed experimental observations, and (2) predict future experiment results, using the calibrated system.

  16. Experimental study on the effects of the number of heat exchanger modules on thermal characteristics in a premixed combustion system

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Byeonghun; Lee, Chang-Eon [Inha University, Incheon (Korea, Republic of); Kum, Sung Min [Halla University, Wonju (Korea, Republic of); Lee, Seungro [Chonbuk National University, Jeonju (Korea, Republic of)

    2016-01-15

    The effects of the number of heat exchanger modules on thermal characteristics were experimentally studied in a premixed combustion system with a cross-flow staggered-tube heat exchanger. The various heat exchanger modules, from 4 to 8, combined with a premixed burner were tested to investigate the performance of the heat exchanger through the surface area of the heat exchanger at various equivalence ratios. Additionally, the performance of the heat exchanger was analyzed by applying entropy generation theory to the heat exchanger system. As a result, although the heat transfer rate increases with the increase of the equivalence ratio, the NOx and CO concentrations also increase due to the increasing flame temperature. In addition, the entropy generation increases with an increase of the equivalence ratio. Furthermore, the heat transfer rate and the effectiveness are increased with the increase of the number of the heat exchanger modules. Also, the effectiveness is sharply increased when the number of the heat exchanger modules is increased from 4 to 5. Consequently, the optimal operating conditions regarding pollutant emission, effectiveness and entropy generation in this experimental range are 0.85 for the equivalence ratio and 8 for the number of heat exchanger modules.

  17. Numerical analysis of flow interaction of turbine system in two-stage turbocharger of internal combustion engine

    Science.gov (United States)

    Liu, Y. B.; Zhuge, W. L.; Zhang, Y. J.; Zhang, S. Y.

    2016-05-01

    To reach the goal of energy conservation and emission reduction, high intake pressure is needed to meet the demand of high power density and high EGR rate for internal combustion engine. Present power density of diesel engine has reached 90KW/L and intake pressure ratio needed is over 5. Two-stage turbocharging system is an effective way to realize high compression ratio. Because turbocharging system compression work derives from exhaust gas energy. Efficiency of exhaust gas energy influenced by design and matching of turbine system is important to performance of high supercharging engine. Conventional turbine system is assembled by single-stage turbocharger turbines and turbine matching is based on turbine MAP measured on test rig. Flow between turbine system is assumed uniform and value of outlet physical quantities of turbine are regarded as the same as ambient value. However, there are three-dimension flow field distortion and outlet physical quantities value change which will influence performance of turbine system as were demonstrated by some studies. For engine equipped with two-stage turbocharging system, optimization of turbine system design will increase efficiency of exhaust gas energy and thereby increase engine power density. However flow interaction of turbine system will change flow in turbine and influence turbine performance. To recognize the interaction characteristics between high pressure turbine and low pressure turbine, flow in turbine system is modeled and simulated numerically. The calculation results suggested that static pressure field at inlet to low pressure turbine increases back pressure of high pressure turbine, however efficiency of high pressure turbine changes little; distorted velocity field at outlet to high pressure turbine results in swirl at inlet to low pressure turbine. Clockwise swirl results in large negative angle of attack at inlet to rotor which causes flow loss in turbine impeller passages and decreases turbine

  18. High Fidelity Tool for Turbulent Combustion in Liquid Launch Propulsion Systems Based on Spray-Flamelet Methodology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation proposed here is a high-performance, high-fidelity simulation capability for simulating liquid rocket spray combustion based on a novel spray-flamelet...

  19. Catalytic Combustion of Gasified Waste

    Energy Technology Data Exchange (ETDEWEB)

    Kusar, Henrik

    2003-09-01

    This thesis concerns catalytic combustion for gas turbine application using a low heating-value (LHV) gas, derived from gasified waste. The main research in catalytic combustion focuses on methane as fuel, but an increasing interest is directed towards catalytic combustion of LHV fuels. This thesis shows that it is possible to catalytically combust a LHV gas and to oxidize fuel-bound nitrogen (NH{sub 3}) directly into N{sub 2} without forming NO{sub x} The first part of the thesis gives a background to the system. It defines waste, shortly describes gasification and more thoroughly catalytic combustion. The second part of the present thesis, paper I, concerns the development and testing of potential catalysts for catalytic combustion of LHV gases. The objective of this work was to investigate the possibility to use a stable metal oxide instead of noble metals as ignition catalyst and at the same time reduce the formation of NO{sub x} In paper II pilot-scale tests were carried out to prove the potential of catalytic combustion using real gasified waste and to compare with the results obtained in laboratory scale using a synthetic gas simulating gasified waste. In paper III, selective catalytic oxidation for decreasing the NO{sub x} formation from fuel-bound nitrogen was examined using two different approaches: fuel-lean and fuel-rich conditions. Finally, the last part of the thesis deals with deactivation of catalysts. The various deactivation processes which may affect high-temperature catalytic combustion are reviewed in paper IV. In paper V the poisoning effect of low amounts of sulfur was studied; various metal oxides as well as supported palladium and platinum catalysts were used as catalysts for combustion of a synthetic gas. In conclusion, with the results obtained in this thesis it would be possible to compose a working catalytic system for gas turbine application using a LHV gas.

  20. SIMULACIÓN BIDIMENSIONAL DE UN SISTEMA DE COMBUSTIÓN INESTABLE TWO-DIMENSIONAL SIMULATION OF AN UNSTABLE COMBUSTION SYSTEM

    Directory of Open Access Journals (Sweden)

    Javier Achury Varila

    2010-04-01

    Full Text Available La inestabilidad en la combustión es una condición indeseada en algunos sistemas de combustión como en turbinas de gas por ejemplo. Se refiere a la presencia autogenerada de oscilaciones en la presión que pueden afectar a la cámara de combustión y de paso llegar a generar ruido. Una reciente tendencia generalizada en los procesos de combustión apunta al uso de mezclas pobres para la reducción de contaminantes, no obstante que este tipo de mezclas son más susceptibles a la inestabilidad en la combustión. Las complicadas relaciones que gobiernan el fenómeno se pueden resumir como el acoplamiento entre la llama y la acústica del sistema. En el presente trabajo se presenta un planteamiento numérico que permite aproximarse al fenómeno a través de la solución de un modelo de combustión básico implementado computacionalmente. En este modelo se simula una autoexcitación del sistema a través de oscilaciones en la entrada de flujos de reactantes. Finalmente, se comparan los resultados de la simulación numérica con otras simulaciones y datos experimentales.The Combustion instability is an undesirable condition reached in some combustion systems, as during the operation of gas turbines. It refers to self-excited oscillations of pressure that may affect the combustion chamber and generate noise. A recent generalized tendency in combustion processes aims to the use of lean combustion (low fuel/air ratios for pollutants reduction, nevertheless this sort of mixtures are more susceptible to combustion instabilities. The complex relationship that generates the phenomenon can be summarized as the coupling between flame and acoustics. In this paper it is outlined a numerical approach to this phenomenon by solving a basic computational combustion model (by Direct Numerical Simulation. In this model a self-excited system is simulated through imposed oscillations in reactants flows. Finally, results for this numerical simulation are compared

  1. Combustion-derived nanoparticles, the neuroenteric system, cervical vagus, hyperphosphorylated alpha synuclein and tau in young Mexico City residents.

    Science.gov (United States)

    Calderón-Garcidueñas, Lilian; Reynoso-Robles, Rafael; Pérez-Guillé, Beatriz; Mukherjee, Partha S; Gónzalez-Maciel, Angélica

    2017-11-01

    Mexico City (MC) young residents are exposed to high levels of fine particulate matter (PM2.5), have high frontal concentrations of combustion-derived nanoparticles (CDNPs), accumulation of hyperphosphorylated aggregated α-synuclein (α-Syn) and early Parkinson's disease (PD). Swallowed CDNPs have easy access to epithelium and submucosa, damaging gastrointestinal (GI) barrier integrity and accessing the enteric nervous system (ENS). This study is focused on the ENS, vagus nerves and GI barrier in young MC v clean air controls. Electron microscopy of epithelial, endothelial and neural cells and immunoreactivity of stomach and vagus to phosphorylated ɑ-synuclein Ser129 and Hyperphosphorylated-Tau (Htau) were evaluated and CDNPs measured in ENS. CDNPs were abundant in erythrocytes, unmyelinated submucosal, perivascular and intramuscular nerve fibers, ganglionic neurons and vagus nerves and associated with organelle pathology. ɑSyn and Htau were present in 25/27 MC gastric,15/26 vagus and 18/27 gastric and 2/26 vagus samples respectively. We strongly suggest CDNPs are penetrating and damaging the GI barrier and reaching preganglionic parasympathetic fibers and the vagus nerve. This work highlights the potential role of CDNPs in the neuroenteric hyperphosphorylated ɑ-Syn and tau pathology as seen in Parkinson and Alzheimer's diseases. Highly oxidative, ubiquitous CDNPs constitute a biologically plausible path into Parkinson's and Alzheimer's pathogenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Investigation of a rotary valving system with variable valve timing for internal combustion engines: Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Cross, P.C.; Hansen, C.N.

    1994-11-18

    The objective of the program was to provide a functional demonstration of the Hansen Rotary Valving System with Variable Valve timing (HRVS/VVT), capable of throttleless inlet charge control, as an alternative to conventional poppet-valves for use in spark ignited internal combustion engines. The goal of this new technology is to secure benefits in fuel economy, broadened torque band, vibration reduction, and overhaul accessibility. Additionally, use of the variable valve timing capability to vary the effective compression ratio is expected to improve multi-fuel tolerance and efficiency. Efforts directed at the design of HRVS components proved to be far more extensive than had been anticipated, ultimately requiring that proof-trial design/development work be performed. Although both time and funds were exhausted before optical or ion-probe types of in-cylinder investigation could be undertaken, a great deal of laboratory data was acquired during the course of the design/development work. This laboratory data is the basis for the information presented in this Final Report.

  3. INTELLIGENT MONITORING SYSTEM WITH HIGH TEMPERATURE DISTRIBUTED FIBEROPTIC SENSOR FOR POWER PLANT COMBUSTION PROCESSES

    Energy Technology Data Exchange (ETDEWEB)

    Kwang Y. Lee; Stuart S. Yin; Andre Boheman

    2004-12-26

    The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, improvement was made on the performance of in-fiber grating fabricated in single crystal sapphire fibers, test was performed on the grating performance of single crystal sapphire fiber with new fabrication methods, and the fabricated grating was applied to high temperature sensor. Under Task 2, models obtained from 3-D modeling of the Demonstration Boiler were used to study relationships between temperature and NOx, as the multi-dimensionality of such systems are most comparable with real-life boiler systems. Studies show that in boiler systems with no swirl, the distributed temperature sensor may provide information sufficient to predict trends of NOx at the boiler exit. Under Task 3, we investigate a mathematical approach to extrapolation of the temperature distribution within a power plant boiler facility, using a combination of a modified neural network architecture and semigroup theory. The 3D temperature data is furnished by the Penn State Energy Institute using FLUENT. Given a set of empirical data with no analytic

  4. Intelligent Monitoring System With High Temperature Distributed Fiberoptic Sensor For Power Plant Combustion Processes

    Energy Technology Data Exchange (ETDEWEB)

    Kwang Y. Lee; Stuart S. Yin; Andre Boheman

    2005-12-26

    The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, we set up a dedicated high power, ultrafast laser system for fabricating in-fiber gratings in harsh environment optical fibers, successfully fabricated gratings in single crystal sapphire fibers by the high power laser system, and developed highly sensitive long period gratings (lpg) by electric arc. Under Task 2, relevant mathematical modeling studies of NOx formation in practical combustors. Studies show that in boiler systems with no swirl, the distributed temperature sensor may provide information sufficient to predict trends of NOx at the boiler exit. Under Task 3, we investigate a mathematical approach to extrapolation of the temperature distribution within a power plant boiler facility, using a combination of a modified neural network architecture and semigroup theory. The 3D temperature data is furnished by the Penn State Energy Institute using FLUENT. Given a set of empirical data with no analytic expression, we first develop an analytic description and then extend that model along a single axis. Extrapolation

  5. Intelligent Monitoring System with High Temperature Distributed Fiberoptic Sensor for Power Plant Combustion Processes

    Energy Technology Data Exchange (ETDEWEB)

    Kwang Y. Lee; Stuart S. Yin; Andre Boehman

    2006-09-26

    The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system is three fold: (1) development of high temperature distributed fiber optical sensor capable of measuring temperatures greater than 2000 C degree with spatial resolution of less than 1 cm; (2) development of distributed parameter system (DPS) models to map the three-dimensional (3D) temperature distribution for the furnace; and (3) development of an intelligent monitoring system for real-time monitoring of the 3D boiler temperature distribution. Under Task 1, we have set up a dedicated high power, ultrafast laser system for fabricating in-fiber gratings in harsh environment optical fibers, successfully fabricated gratings in single crystal sapphire fibers by the high power laser system, and developed highly sensitive long period gratings (lpg) by electric arc. Under Task 2, relevant mathematical modeling studies of NOx formation in practical combustors have been completed. Studies show that in boiler systems with no swirl, the distributed temperature sensor may provide information sufficient to predict trends of NOx at the boiler exit. Under Task 3, we have investigated a mathematical approach to extrapolation of the temperature distribution within a power plant boiler facility, using a combination of a modified neural network architecture and semigroup theory. Given a set of empirical data with no analytic expression, we first developed an analytic description and then extended that model along a single axis.

  6. Combustion chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.J. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    This research is concerned with the development and use of sensitivity analysis tools to probe the response of dependent variables to model input variables. Sensitivity analysis is important at all levels of combustion modeling. This group`s research continues to be focused on elucidating the interrelationship between features in the underlying potential energy surface (obtained from ab initio quantum chemistry calculations) and their responses in the quantum dynamics, e.g., reactive transition probabilities, cross sections, and thermal rate coefficients. The goals of this research are: (i) to provide feedback information to quantum chemists in their potential surface refinement efforts, and (ii) to gain a better understanding of how various regions in the potential influence the dynamics. These investigations are carried out with the methodology of quantum functional sensitivity analysis (QFSA).

  7. Small scale wood combustion systems and fireplaces. Some existing markets in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Vankerkove, R. [ERBE, Agence Regionale Biomasse Energie, Gembloux (Belgium); Belle, J.F. van; Lemaire, P. [CRA, departement de genie rural, section biomasse, Gembloux (Belgium)

    1998-12-31

    Because they are seen as more economical and more environmental respectful, the national authorities intend usually to promote district heating rather than stoves and little boilers. Nevertheless these systems are yet now a very important source of energy for private houses in many European countries. The use of this kind of systems as primary or secondary tool of heating depends principally of the three following parameters: the percentage of area covered by the forest, the existing traditions concerning the use of wood stoves and the presence of local manufacturers or distributors. The aim of this presentation will be to show the situation and the states of the art in several European countries

  8. Influence of gas composition on the combustion and efficiency of a homogeneous charge compression ignition engine system fuelled with methanol reformed gases

    OpenAIRE

    Shudo, Toshio

    2008-01-01

    A homogeneous charge compression ignition (HCCI) engine system fuelled with dimethyl ether (DME) and methanol-reformed gas (MRG), both produced from methanol by onboard reformers using exhaust heat, has been proposed in previous research. Adjusting the proportions of DME and MRG with different ignition properties effectively controlled the ignition timing and load in HCCI combustion. The use of the single liquid fuel, methanol, also eliminates the inconvenience of carrying two fuels while mai...

  9. The combustion system of the MAN 20V35/44G gas engine; Das Brennverfahren des Gasmotors 20V35/44G von MAN

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Markus; Auer, Matthias; Stiesch, Gunnar [MAN Diesel and Turbo SE, Augsburg (Germany)

    2013-04-15

    The new gas engine 20V35/44G by MAN Diesel and Turbo SE has a power output of 10.6 MW. The high effective efficiency level of 48.4 % as well as numerous technical innovations allow an environment-friendly, economical and reliable engine operation. Key to achieve this is the combustion system, which has been optimised during advanced engineering by means of modern simulation tools and extensive single-cylinder tests. (orig.)

  10. Control methods and valve arrangement for start-up and shutdown of pressurized combustion and gasification systems integrated with a gas turbine

    Science.gov (United States)

    Provol, Steve J.; Russell, David B.; Isaksson, Matti J.

    1994-01-01

    A power plant having a system for converting coal to power in a gas turbine comprises a coal fed pressurized circulating bed for converting coal to pressurized gases, a gas turbine having a compressor for pressurizing air for the pressurized circulating bed and expander for receiving and expanding hot combustion gases for powering a generator, a first fast acting valve for controlling the pressurized air, a second fast acting valve means for controlling pressurized gas from the compressor to the expander.

  11. The Usage of Biogas in Fuel Cell Systems; Utilizacion de Biogas en Pilas de Combustible

    Energy Technology Data Exchange (ETDEWEB)

    Perez Martinez, M.; Cuesta Santianes, M. J.; Nunez Crespi, S.; Cabrera Jimenez, J. A.

    2008-08-06

    The usage of biogas in fuel cell systems is nowadays considered as a promising alternative for energy production worldwide as it involves the use of a valuable residual biomass resource that could enable the obtention of combined heat, cold and power generation very efficiently, while additionally avoiding greenhouse gas emissions to the atmosphere. Both development lines (biogas and fuel cells) and their associated technologies are receiving a great support from the different states, pioneer countries being Japan and U.S.A. The objective of this study is to make a detail analysis of the state of the art of biogas-powered fuel cell systems worldwide. Most representative players in the field are identified through the search of the scientific publications, projects and patent documents in which they are involved. (Author) 18 refs.

  12. The influence of impurities on the operation of selected fuel ignition systems in combustion engines

    Directory of Open Access Journals (Sweden)

    Różowicz Sebastian

    2016-06-01

    Full Text Available The paper attempts to determine the impact of fuel impurities on the spark discharge energy and the wear of the spark plug electrode. Spark plugs were analyzed in two typical configurations of the ignition system. A number of tests were conducted to determine the wear of the spark plug electrode exposed to different types of impurities. The spark discharge energy for new and worn spark plugs was determined through calculation.

  13. CCS on Offshore Oil and Gas Installation - Design of Post Combustion Capture System and Steam Cycle

    OpenAIRE

    Nord, Lars O.; Anantharaman, Rahul; Chikukwa, Actor; Mejdell, Thor

    2017-01-01

    Most of the released CO2 on offshore oil and gas installation originates from the gas turbines that power the installations. For certain offshore installations, CO2 capture and storage (CCS) could be an alternative to decrease the CO2 emissions. When opting for a chemical absorption CO2 capture system, a heat source for the stripper reboiler is needed. Since most offshore installations are powered by simple cycle GTs, there is typically no steam available that could be used for stripper reboi...

  14. Simulation of one-dimensional heat transfer system based on the blended coal combustion

    Science.gov (United States)

    Jin, Y. G.; Li, W. B.; Cheng, Z. S.; Cheng, J. W.; liu, Y.

    2017-12-01

    In this paper, the supercritical boiler thermodynamic calculation model is studied. Three types of heat exchangers are proposed, namely furnace (total radiation type), semi-radiation and convection, and discussed. Two cases were simulated - mixing of two bituminous coals and mixing of a bituminous coal and lignite- order to analyze the performance on the flue gas side. The study shows that the influence of flue air leakage and gas distribution coefficient on the system.

  15. System of leak inspection of irradiated fuel; Sistema de inspeccion de fuga de combustible irradiado

    Energy Technology Data Exchange (ETDEWEB)

    Delfin L, A.; Castaneda J, G.; Mazon R, R.; Aguilar H, F. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: rmr@nuclear.inin.mx

    2007-07-01

    The International Atomic Energy Agency (IAEA) through the project RLA/04/18 Irradiated Fuel Management in Research reactors, recommended among other that the participant countries (Brazil, Argentina, Chile, Peru and Mexico), develop the sipping tool to generate registrations of the state that keep the irradiated fuels in the facilities of each country. The TRIGA Mark lll Reactor (RTMIII) Department, generated a project that it is based on the dimensions of the used fuel by the RTMIII, for design and to build an inspection system of irradiated fuel well known as SIPPING. This technique, provides a high grade of accuracy in the detection of gassy fission products or liquids that escape from the enveloping of fuels that have flaws or flights. The operation process of the SIPPING is carried out generating the migration of fission products through the creation of a pressure differential gas or vacuum to identify fuel assemblies failed by means of the detection of the xenon and/or krypton presence. The SIPPING system, is a device in revolver form with 4 tangential nozzles, which will discharge the fluid between the external surface of the enveloping of the fuel and the interior surface of the encircling one; the device was designed with independent pieces, with threaded joining and with stamps to impede flights of the fluid toward the exterior of the system. The System homogenizes and it distributes the fluid pressure so that the 4 nozzles work to equality of conditions, for what the device was designed in 3 pieces, an internal that is denominated revolver, one external that calls cover, and a joining called mamelon that will unite with the main encircling of the system. The detection of fission products in failed fuels, its require that inside the encircling one where the irradiated fuel element is introduced, be generated a pressure differential of gas or vacuum, and that it allows the samples extraction of water. For what generated a top for the encircling with the

  16. Substructuring of multibody systems for numerical transfer path analysis in internal combustion engines

    Science.gov (United States)

    Acri, Antonio; Offner, Guenter; Nijman, Eugene; Rejlek, Jan

    2016-10-01

    Noise legislations and the increasing customer demands determine the Noise Vibration and Harshness (NVH) development of modern commercial vehicles. In order to meet the stringent legislative requirements for the vehicle noise emission, exact knowledge of all vehicle noise sources and their acoustic behavior is required. Transfer path analysis (TPA) is a fairly well established technique for estimating and ranking individual low-frequency noise or vibration contributions via the different transmission paths. Transmission paths from different sources to target points of interest and their contributions can be analyzed by applying TPA. This technique is applied on test measurements, which can only be available on prototypes, at the end of the designing process. In order to overcome the limits of TPA, a numerical transfer path analysis methodology based on the substructuring of a multibody system is proposed in this paper. Being based on numerical simulation, this methodology can be performed starting from the first steps of the designing process. The main target of the proposed methodology is to get information of noise sources contributions of a dynamic system considering the possibility to have multiple forces contemporary acting on the system. The contributions of these forces are investigated with particular focus on distribute or moving forces. In this paper, the mathematical basics of the proposed methodology and its advantages in comparison with TPA will be discussed. Then, a dynamic system is investigated with a combination of two methods. Being based on the dynamic substructuring (DS) of the investigated model, the methodology proposed requires the evaluation of the contact forces at interfaces, which are computed with a flexible multi-body dynamic (FMBD) simulation. Then, the structure-borne noise paths are computed with the wave based method (WBM). As an example application a 4-cylinder engine is investigated and the proposed methodology is applied on the

  17. External Combustion Engine Technology (Vapor and Liquid Cycles) for Individual Soldier Power Systems

    Science.gov (United States)

    1992-04-01

    ll.) (hi.1) (11)) Molor-gellnraht - 7.00 7.00 5.00 245.0* 0.3 housing Fuel tard , -- 13.25 10.(K) 1.25 165.61, 0.3 System battery - 7.00 1.00 3.00 21.0...K. Gabriel Attn: Tech Library Attn: SARD-TT, F. Milton WreM� Attn: SAR.D-TT, S. VannucciWarnMI43750 Washington, DC 203 10-0 100 US Army Troop

  18. Integrated Advanced Reciprocating Internal Combustion Engine System for Increased Utilization of Gaseous Opportunity Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Pratapas, John [Gas Technology Inst., Des Plaines, IL (United States); Zelepouga, Serguei [Gas Technology Inst., Des Plaines, IL (United States); Gnatenko, Vitaliy [Gas Technology Inst., Des Plaines, IL (United States); Saveliev, Alexei [North Carolina State Univ., Raleigh, NC (United States); Jangale, Vilas [North Carolina State Univ., Raleigh, NC (United States); Li, Hailin [West Virginia Univ., Morgantown, WV (United States); Getz, Timothy [West Virginia Univ., Morgantown, WV (United States); Mather, Daniel [Digital Engines, New York, NY (United States)

    2013-08-31

    The project is addressing barriers to or opportunities for increasing distributed generation (DG)/combined heat and power (CHP) use in industrial applications using renewable/opportunity fuels. This project brings together novel gas quality sensor (GQS) technology with engine management for opportunity fuels such as landfill gas, digester gas and coal bed methane. By providing the capability for near real-time monitoring of the composition of these opportunity fuels, the GQS output can be used to improve the performance, increase efficiency, raise system reliability, and provide improved project economics and reduced emissions for engines used in distributed generation and combined heat and power.

  19. System and method for improving performance of a fluid sensor for an internal combustion engine

    Science.gov (United States)

    Kubinski, David [Canton, MI; Zawacki, Garry [Livonia, MI

    2009-03-03

    A system and method for improving sensor performance of an on-board vehicle sensor, such as an exhaust gas sensor, while sensing a predetermined substance in a fluid flowing through a pipe include a structure for extending into the pipe and having at least one inlet for receiving fluid flowing through the pipe and at least one outlet generally opposite the at least one inlet, wherein the structure redirects substantially all fluid flowing from the at least one inlet to the sensor to provide a representative sample of the fluid to the sensor before returning the fluid through the at least one outlet.

  20. Combustion control and model based optimization. Modeling of combustion process and development of supporting control systems for plant operation; Palamisprosessin saeaetoe ja mallipohjainen optimointi; Voimalaitoksen polttoprosessin mallitus ja saeaetoe sekae operoinnin tukiohjelmien kehitys ja testaus

    Energy Technology Data Exchange (ETDEWEB)

    Kortela, U.; Mononen, J.; Leppaekoski, K.; Hiltunen, J.; Jouppila, M.; Karppinen, R. [Oulu Univ. (Finland). Systems Engineering Lab.

    1997-10-01

    The aims of the project are to develop the combustion control strategies and to minimize the flue gas emissions. The common goal of the studies has been the reduction of flue gas emissions by using advanced control and optimization methods. The behaviour of different kind of boilers and fuels has been modelled using experimental data from fullscale plants, such as a 42 MW bubbling fluidized bed boiler, 23 MW bubbling fluidized bed boiler and a 300 MW circulating fluidized bed boiler. Many of the individual observations and modelled correlations between control variables and flue gas emissions have lead to operation instructions and/or re-organized control schemes which help to control total emissions. The most part of this knowledge can be formed to the standard IF- THEN - type rules which contain some uncertainty or fuzziness. Rule-based instruction system for the reduction of flue gas emissions is under work. (orig.)

  1. Real-Time Identification of Smoldering and Flaming Combustion Phases in Forest Using a Wireless Sensor Network-Based Multi-Sensor System and Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Xiaofei Yan

    2016-08-01

    Full Text Available Diverse sensing techniques have been developed and combined with machine learning method for forest fire detection, but none of them referred to identifying smoldering and flaming combustion phases. This study attempts to real-time identify different combustion phases using a developed wireless sensor network (WSN-based multi-sensor system and artificial neural network (ANN. Sensors (CO, CO2, smoke, air temperature and relative humidity were integrated into one node of WSN. An experiment was conducted using burning materials from residual of forest to test responses of each node under no, smoldering-dominated and flaming-dominated combustion conditions. The results showed that the five sensors have reasonable responses to artificial forest fire. To reduce cost of the nodes, smoke, CO2 and temperature sensors were chiefly selected through correlation analysis. For achieving higher identification rate, an ANN model was built and trained with inputs of four sensor groups: smoke; smoke and CO2; smoke and temperature; smoke, CO2 and temperature. The model test results showed that multi-sensor input yielded higher predicting accuracy (≥82.5% than single-sensor input (50.9%–92.5%. Based on these, it is possible to reduce the cost with a relatively high fire identification rate and potential application of the system can be tested in future under real forest condition.

  2. Real-Time Identification of Smoldering and Flaming Combustion Phases in Forest Using a Wireless Sensor Network-Based Multi-Sensor System and Artificial Neural Network.

    Science.gov (United States)

    Yan, Xiaofei; Cheng, Hong; Zhao, Yandong; Yu, Wenhua; Huang, Huan; Zheng, Xiaoliang

    2016-08-04

    Diverse sensing techniques have been developed and combined with machine learning method for forest fire detection, but none of them referred to identifying smoldering and flaming combustion phases. This study attempts to real-time identify different combustion phases using a developed wireless sensor network (WSN)-based multi-sensor system and artificial neural network (ANN). Sensors (CO, CO₂, smoke, air temperature and relative humidity) were integrated into one node of WSN. An experiment was conducted using burning materials from residual of forest to test responses of each node under no, smoldering-dominated and flaming-dominated combustion conditions. The results showed that the five sensors have reasonable responses to artificial forest fire. To reduce cost of the nodes, smoke, CO₂ and temperature sensors were chiefly selected through correlation analysis. For achieving higher identification rate, an ANN model was built and trained with inputs of four sensor groups: smoke; smoke and CO₂; smoke and temperature; smoke, CO₂ and temperature. The model test results showed that multi-sensor input yielded higher predicting accuracy (≥82.5%) than single-sensor input (50.9%-92.5%). Based on these, it is possible to reduce the cost with a relatively high fire identification rate and potential application of the system can be tested in future under real forest condition.

  3. 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

  4. Fuel visual inspection system of the RTMIII; Sistema de inspeccion visual de combustible del RTMIII

    Energy Technology Data Exchange (ETDEWEB)

    Delfin L, A.; Castaneda J, G.; Mazon R, R.; Aguilar H, F. [ININ, Km. 36.5 Carretera Mexico-Toluca, Ocoyoacac, 52245 Estado de Mexico (Mexico)]. e-mail: rmr@nuclear.inin.mx

    2007-07-01

    The International Atomic Energy Agency (IAEA) through the RLA/04/18 project, Management of Irradiated Fuel in Research Reactors, it recommended among other that the participant countries (Brazil, Argentina, Chile, Peru and Mexico), develop tools to assure the integrity of the nuclear fuels used in the research reactors. The TRIGA Mark lll reactor (RTMIII) of the ININ, designed and built a system of visual inspection, that it uses a high radiation camera and image digitalisation. The project considers safety conditions of the personnel that carried out the activities of visual inspection, for that which the tool dives in the pool of the RTMIII, being held by an end in the superior part of the aluminium liner of the Reactor like it is shown in the plane No. 1. The primordial unit of the system is the visual equipment that corresponds to a camera of the Hydro-Technologie (HYTEC) VSLT 410N mark, designed to work in atmospheres under the water and/or in places of high risk. The camera has an unit of motorized orientation of stainless steel that can be rotated unboundedly in both senses, with variable speed by means of a control lever from the control unit. Together to this orientation unit is found the camera head, the one which is contained in an unit of motorized inclination of stainless steel that can be rotated azimuthally up to 370 degrees in both senses. The operation conditions of the camera are the following ones, temperature: 0 to 50 C, dose speed: {<=} 50 rad/h, operation depth: {<=} 30 mts, humidity (control unit): {<=} 80%. From the control unit it is derived an external device plug-n-play TV-Usb Aver Media marks whose function is to decode the video signal sent by the control unit and to transmit it to the computer where the image is captured in picture or video that is analyzed later on with any software ad hoc, that in our case we use the Quantikov Image Analyzer program for Windows 98 of the Dr. Lucio C. M. Pinto from Brazil who participates in the RLA

  5. Increased combustion stability in modulating biomass boilers for district heating systems. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Zethraeus, Bjoern; Olsson, Pernilla; Gummesson, Martin [Vaexjoe Univ. (Sweden). Dep. of Bioenergy Technology

    2002-04-01

    The ultimate aim of the development work performed at ITN was to provide a tool for the boiler designer, a tool to make good estimates as to the environmental performance of different boiler designs. In the longer perspective, such a predictive model may also be developed into a process control system predictor and thus improve boiler control with respect to dynamic mixing imperfections. To fulfil this aim there also has to be available a sufficiently fast measurement technique and part of ITN's work aimed at demonstrating that by digital methods may the time resolution of measured data be improved. The main deliverables from ITN were planned to be: A description of an algorithm to improve the time resolution of measured data by aid of digital back-calculation to provide measurement data with a time resolution comparable to the computational model with the lowest possible demands on measurement frequency. A transportable computer code to describe the dynamic behaviour of biomass-fired boilers with respect to hydrocarbon-, CO- and NO{sub x}-emissions. The program should be able to predict the distribution of concentrations of these gas components in a reasonably short computing time. An algorithm based on the use of Fourier transforms has been derived and tested of-line. Provided the gas analysis sampling system has a time constant r for its low-pass characteristic, even noisy signals may be reconstructed into time constant {tau}/2 if a clever filter is used to improve the signal/noise ratio. Further improvement is theoretically possible - but seems not realistic in practical cases. A computer code has been produced in MATLAB, a code that reproduces the dynamic mixing behaviour of realistic boilers. The most fundamental assumptions for the code have not been thoroughly verified but a number of comparisons have been made to different boilers and seem to indicate that the predictions are qualitatively correct. The code is based on a constant flow of fuel

  6. A systems approach to risk assessment: Application to methylmercury from coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Saroff, L. [Dept. of Energy, Washington, DC (United States); Lipfert, F.W.; Moskowitz, P.D. [Brookhaven National Lab., Upton, NY (United States)

    1995-01-01

    The Department of Energy (DOE) asked Brookhaven National Laboratory (BNL) to perform a probabilistic assessment of the health risks associated with Hg from coal-fired power plants. The objective of the assessment is to estimate the incremental health risks that might ensue from a typical coal-fired power plant, together with their uncertainties, taking into account existing background levels and the actual adverse health effects that have previously been associated with exposure to various Hg species. Mercury has a long history of association with adverse neurological effects at high exposure levels. The most important current exposure pathway has been found to be ingestion of fish containing methylmercury (MeHg), which is the end product of bioconcentration moving up the aquatic food chain. Mercury can enter natural waters from either industrial discharges or from atmospheric deposition of various inorganic Ho. compounds. Because of the worldwide background and the existence of local emissions sources, Hg deposition must be considered on local, regional and global scales. The regulatory technical challenge presented by methy1mercury is to protect public health without foreclosing an appreciable a portion of the food supply or impacting on the lifestyles of North American native populations. This paper presents an abbreviated account of the DOE/BNL risk assessment, as viewed from a systems perspective. We review the structure of the model, the sources of data used, the assumptions that were made, and the interpretation of the findings. Since publication of the first risk assessment report, we have refined our estimates of local atmospheric dispersion and deposition and {open_quotes}calibrated{close_quotes} the pharmacokinetic portion of the model against observations.

  7. Air quality and residential wood combustion - application of the model system SIMAIRrwc for some Swedish municipalities; Luftkvalitet och smaaskalig biobraensleeldning. Tillaempningar av SIMAIRved foer naagra kommuner

    Energy Technology Data Exchange (ETDEWEB)

    Omstedt, Gunnar; Andersson, Stefan; Johansson, Christer; Loefgren, Bengt-Erik

    2008-11-15

    SIMAIRrwc is a Web based evaluation tool for meeting the EU directive on air pollution limits in residential areas using wood combustion. The background is a four-year research program (2001-2004) called Biomass Combustion Health and Environment. Some conclusions from this program were that emissions from small scale wood combustion can influence human health mainly due to high emitting old wood stoves during cold weather conditions and that the air quality in such areas can improve significantly if old wood stoves were replaced by modern wood boilers attached to a storage tank or with a pellet boiler. SIMAIRrwc is based on the same principles as SIMAIRroad, which is a Web based evaluation tool for road traffic i.e. coupled model system using different models on local, urban and regional geographical scales, best available emission data, but at the same time presented in a very simplified way. In this project SIMAIRrwc has been applied in five different Swedish municipalities. The aim has been to apply and improve the model in cooperation with the municipalities. The conclusions from the project are: Small scale wood combustions in residential areas are local problems which sometimes include only a few houses and/or wood-burners. Air quality problems related to the EU directive are mainly due to particles. Combinations of residential areas with wood combustion and emissions from nearby dense traffic roads might give rise to bad air quality. Actions require knowledge about individual equipment which needs information from the local chimney sweeps. The best way to identify problem areas is to use model calculations. If model calculations indicate risks of exceeding air quality limits, then new calculations should be made with improved input data taking into account for example information of district heating or other installations that can effect the emissions. Before actions are taken it may also be useful to make measurements. The measurement site can then be

  8. Internal combustion piston engines

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C.L.

    1977-07-01

    Current worldwide production of internal combustion piston engines includes many diversified types of designs and a very broad range of sizes. Engine sizes range from a few horsepower in small mobile units to over 40,000 brake horsepower in large stationary and marine units. The key characteristics of internal combustion piston engines considered appropriate for use as prime movers in Integrated Community Energy Systems (ICES) are evaluated. The categories of engines considered include spark-ignition gas engines, compression-ignition oil (diesel) engines, and dual-fuel engines. The engines are evaluated with respect to full-load and part-load performance characteristics, reliability, environmental concerns, estimated 1976 cost data, and current and future status of development. The largest internal combustion piston engines manufactured in the United States range up to 13,540 rated brake horsepower. Future development efforts are anticipated to result in a 20 to 25% increase in brake horsepower without increase in or loss of weight, economy, reliability, or life expectancy, predicated on a simple extension of current development trends.

  9. DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS-FIRED COMBUSTION SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Glenn C. England

    2004-10-20

    In 1997, the United States Environmental Protection Agency (EPA) promulgated new National Ambient Air Quality Standards (NAAQS) for particulate matter, including for the first time particles with aerodynamic diameter smaller than 2.5 micrometers ({micro}m) referred to as PM2.5. PM2.5 in the atmosphere also contributes to reduced atmospheric visibility, which is the subject of existing rules for siting emission sources near Class 1 areas and new Regional Haze rules. There are few existing data regarding emissions and characteristics of fine aerosols from oil, gas and power generation industry combustion sources, and the information that is available is generally outdated and incomplete. Traditional stationary source air emission sampling methods tend to underestimate or overestimate the contribution of the source to ambient aerosols because they do not properly account for primary aerosol formation, which occurs after the gases leave the stack. Primary aerosol includes both filterable particles that are solid or liquid aerosols at stack temperature plus those that form as the stack gases cool through mixing and dilution processes in the plume downwind of the source. These deficiencies in the current methods can have significant impacts on regulatory decision-making. PM2.5 measurement issues were extensively reviewed by the American Petroleum Institute (API) (England et al., 1998), and it was concluded that dilution sampling techniques are more appropriate for obtaining a representative particulate matter sample from combustion systems for determining PM2.5 emission rate and chemical speciation. Dilution sampling is intended to collect aerosols including those that condense and/or react to form solid or liquid aerosols as the exhaust plume mixes and cools to near-ambient temperature immediately after the stack discharge. These techniques have been widely used in recent research studies. For example, Hildemann et al. (1994) and McDonald et al. (1998) used filtered

  10. Design and Construction of a Thermophotovoltaic Energy Conversion System Using Combustion Gases from a T-58 Gas Turbine

    National Research Council Canada - National Science Library

    Erickson, Timothy

    1997-01-01

    ...) generator that uses a General Electric T-58 gas turbine as the heat source. The combustion gas was tapped from the T-58's combustor through an ignitor port and then extracted through a silicon carbide composite tube into a ceramic emitter...

  11. Use of aromatic salts for simultaneously removing SO.sub.2 and NO.sub.x pollutants from exhaust of a combustion system

    Science.gov (United States)

    Levendis, Yiannis A.; Wise, Donald L.

    1994-10-04

    A method is disclosed for removing pollutants from the exhaust of combustion systems burning fuels containing substantial amounts of sulfur and nitrogen. An exemplary method of the invention involves the formation and reaction of a sorbent comprising calcium benzoate. The calcium benzoate is either dry-sprayed (in the form of a fine powder) or wet-sprayed in an aqueous solution in a high temperature environment such as a combustion chamber. The latter technique is feasible since calcium benzoate is a water-soluble form of calcium. When the dispersed particles of calcium benzoate are heated to a high temperature, the organic benzoate burns off and fine calcium oxide particles are formed. These particles are cenospheric (hollow) and have thin and highly porous walls, thus, affording optimum external and internal accessibility for reacting with toxic gaseous emissions such as SO.sub.2. Further, the combustion of the organic benzoate portion of the sorbent results in the conversion of NO.sub.x to N.sub.2.

  12. Pollutant Formation in Monodisperse Fuel Spray Combustion

    Science.gov (United States)

    Cernansky, N. P.; Sarv, H.

    1983-01-01

    The combustion of liquid sprays represents an extremely important class of combustion processes. In the transition region, encompassing droplet sizes in the range of 25-80 micron diameter, the mixing and evaporation processes are both incomplete at the flame front and burning occurs in a combined diffusive and premixed fashion. Under these conditions, the relative importance of heterogeneous and homogeneous effects in dominating the combustion process is switched and gives rise to a number of interesting phenomena. NO (sub x) formation in monodisperse spray combustion was investigated with the following specific objectives: (1) to quantitatively determine the effect of droplet size, number density, etc. on NO sub x formation in monodisperse fuel spray combustion; and (2) to isolate the important physical and chemical phenomena in NO sub x formation in these combustion systems.

  13. Sandia Combustion Research Program: Annual report, 1986

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    This report presents research results of the past year, divided thematically into some ten categories. Publications and presentations arising from this work are included in the appendix. Our highlighted accomplishment of the year is the announcement of the discovery and demonstration of the RAPRENOx process. This new mechanism for the elimination of nitrogen oxides from essentially all kinds of combustion exhausts shows promise for commercialization, and may eventually make a significant contribution to our nation's ability to control smog and acid rain. The sections of this volume describe the facility's laser and computer system, laser diagnostics of flames, combustion chemistry, reacting flows, liquid and solid propellant combustion, mathematical models of combustion, high-temperature material interfaces, studies of engine/furnace combustion, coal combustion, and the means of encouraging technology transfer. 182 refs., 170 figs., 12 tabs.

  14. Fuel gas combustion research at METC

    Energy Technology Data Exchange (ETDEWEB)

    Norton, T.S.

    1995-06-01

    The in-house combustion research program at METC is an integral part of many METC activities, providing support to METC product teams, project managers, and external industrial and university partners. While the majority of in-house combustion research in recent years has been focussed on the lean premixed combustion of natural gas fuel for Advanced Turbine Systems (ATS) applications, increasing emphasis is being placed on issues of syngas combustion, as the time approaches when the ATS and coal-fired power systems programs will reach convergence. When the METC syngas generator is built in 1996, METC will have the unique combination of mid-scale pressurized experimental facilities, a continuous syngas supply with variable ammonia loading, and a team of people with expertise in low-emissions combustion, chemical kinetics, combustion modeling, combustion diagnostics, and the control of combustion instabilities. These will enable us to investigate such issues as the effects of pressure, temperature, and fuel gas composition on the rate of conversion of fuel nitrogen to NOx, and on combustion instabilities in a variety of combustor designs.

  15. Inhibiting Fe–Al Spinel Formation on a Narrowed Mesopore-Sized MgAl2O4 Support as a Novel Catalyst for H2 Production in Chemical Looping Technology

    Directory of Open Access Journals (Sweden)

    Ali Hafizi

    2018-01-01

    Full Text Available In this paper, the structure of Al2O3 is modified with magnesium to synthesize MgAl2O4 as an oxygen carrier (OC support. The surface properties and structural stability of the modified support are improved by the incorporation of magnesium in the structure of the support and additionally by narrowing the pore size distribution (about 2.3 nm. Then, iron oxide is impregnated on both an Al2O3 support and a MgAl2O4 support as the oxygen transfer active site. The XRD results showed the formation of solely Fe2O3 on the MgAl2O4 support, while both Fe2O3 and Fe3O4 are detected in the synthesized Fe2O3-Al2O3 structure. The synthesized samples are investigated in chemical looping cycles, including CO reduction (as one of the most important side reactions of chemical looping reforming, at different temperatures (300–500 °C and oxidation with steam at 700 °C for hydrogen production. The obtained results showed the inhibition of Fe–Al spinel formation in the structure of the Fe2O3-MgAl2O4 OC. In addition, H2 with a purity higher than 98% is achievable in oxidation of the OC with steam. In addition, the activity and crystalline change of the Fe2O3-MgAl2O4 OC is investigated after 20 reduction-oxidation cycles.

  16. Staged combustion with piston engine and turbine engine supercharger

    Science.gov (United States)

    Fischer, Larry E [Los Gatos, CA; Anderson, Brian L [Lodi, CA; O'Brien, Kevin C [San Ramon, CA

    2011-11-01

    A combustion engine method and system provides increased fuel efficiency and reduces polluting exhaust emissions by burning fuel in a two-stage combustion system. Fuel is combusted in a piston engine in a first stage producing piston engine exhaust gases. Fuel contained in the piston engine exhaust gases is combusted in a second stage turbine engine. Turbine engine exhaust gases are used to supercharge the piston engine.

  17. Chemical kinetics and combustion modeling

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.A. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    The goal of this program is to gain qualitative insight into how pollutants are formed in combustion systems and to develop quantitative mathematical models to predict their formation rates. The approach is an integrated one, combining low-pressure flame experiments, chemical kinetics modeling, theory, and kinetics experiments to gain as clear a picture as possible of the process in question. These efforts are focused on problems involved with the nitrogen chemistry of combustion systems and on the formation of soot and PAH in flames.

  18. 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. .

  19. A comparative study of combustible cartridge case materials

    Directory of Open Access Journals (Sweden)

    Wei-tao Yang

    2017-06-01

    Full Text Available Foamed combustible material based on polymer bonded RDX was fabricated using CO2 as foaming agent. The inner structures of felted and foamed combustible materials were presented by SEM. The two materials presented different formulations and inner porous structures. The combustion behaviors of felted and foamed materials were investigated by closed vessel test. Simultaneously, the co-combustion behavior of combustible cartridge case with 7-perf consolidated propellants was also investigated. The results of closed vessel test is applicable to gun system which is made of the foamed combustible material as component.

  20. Volumetric Combustion Diagnostics

    Science.gov (United States)

    2017-01-03

    i.e., the central plane of the burner and the plane where the PLIF measurement was taken) was extracted and plotted in Fig. 7b. Fig. 7c directly...Hsu, Particle Image Velocimetry in a Nonreacting and Reacting High-Speed Cavity, Journal of Propulsion and Power, 30(3) (2014) 576-591. [7] Y.W...quantitative laser sensors to kinetics, propulsion and practical energy systems, Proceedings of the Combustion Institute, 33(1) (2011) 1-40. [13] A.W

  1. Self-Exited Oscillation in a Combustion Chamber Driven by Phase Change in the Liquid Fuel Feed System

    Directory of Open Access Journals (Sweden)

    C. Hassa

    2011-12-01

    Full Text Available A new mechanism for the generation of a self-exited oscillation of combustion in a generic combustion chamber typical for aeroengine combustors is described. The cause of the oscillation is the phase change from liquid to vapour which happens when the preheat temperature of the air flowing through the burner exceeds the boiling temperature at the operating pressure and the fuel flow is so low that heat transfer to the liquid fuel causes evaporation within the fuel channels of the burner. Liquid fuel and vapour alternatively enter the airstream of the burner. This leads to an unstable situation for the flame. Measurements of chemiluminescence and liquid fuel show nearly complete extinction and re-ignition for the limit cycle. Prevention of the oscillation is possible by better thermal management of the fuel path.

  2. Emissions from residential combustion of different solid fuels. Roekgasemissioner vid anvaendning av olika fasta braenslen i smaaskaliga system

    Energy Technology Data Exchange (ETDEWEB)

    Rudling, L.

    1983-01-01

    The emission from different types of solid fuels during combustion in residential furnaces and stoves has been investigated. The following fules were investigated: wood pellets, peat-bark pellets, wood chips, wood logs,wood-briquets, peat briquets, lignite briquets, fuel oil. Three different 20-25 kW boilers were used and one stove and one fire place. The flue gases were analysed for carbon dioxide, carbon monoxide, nitrogen oxides, hydrocarbons, particulates, tar and fluoranthen.

  3. Combustion Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — For more than 30 years The Combustion Research Facility (CRF) has served as a national and international leader in combustion science and technology. The need for a...

  4. Experiment on the combined combustion of wood chips and sliced straw at a wood-chip firing system at the Maabjerg plant; Forsoeg med samfyring af flis og snittet halm via flisfyringssystemet paa Maalbjergvaerket

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    As during the last two years there have been insufficient supplies of straw for fuelling purposes in Denmark a number of combustion systems in straw-fuelled district heating plants have been adapted for burning wood other tyupes of biofuels. The aim was to demonstrate possibilities for burning sliced straw with a high moisture content and for managing and combusting various mixtures of straw and wood chips and the Maarbjerg plant in Denmark. The combustion processes are described. It is concluded that the plant must be further adapted in order to burn loose sliced straw efficiently but there were no problems connected to the combustion of a mixture of straw and wood chips. (AB)

  5. JANNAF 37th Combustion Subcommittee Meeting. Volume 1

    Science.gov (United States)

    Fry, Ronald S. (Editor); Gannaway, Mary T. (Editor)

    2000-01-01

    This volume, the first of two volumes is a compilation of 59 unclassified/unlimited-distribution technical papers presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 37th Combustion Subcommittee (CS) meeting held jointly with the 25th Airbreathing Propulsion Subcommittee (APS), 19th Propulsion Systems Hazards Subcommittee (PSHS), and 1st Modeling and Simulation Subcommittee (MSS) meetings. The meeting was held 13-17 November 2000 at the Naval Postgraduate School and Hyatt Regency Hotel, Monterey, California. Topics covered at the CS meeting include: a keynote address on the Future Combat Systems, and review of a new JANNAF Modeling and Simulation Subcommittee, and technical papers on gun propellant burning rate, gun tube erosion, advanced gun propulsion concepts, ETC guns, novel gun propellants; liquid, hybrid and novel propellant combustion; solid propellant combustion kinetics, GAP, ADN and RDX combustion, sandwich combustion, metal combustion, combustion instability, and motor combustion instability.

  6. Development of melting system using oxy-coal combustion; Sekitan chokusetsu riyo kinzoku yoyu system gijutsu (NSR) (pilot setsubi unten jokyo ni tsuite)

    Energy Technology Data Exchange (ETDEWEB)

    Sugiyama, T. [Center for Coal Utilization, Japan, Tokyo (Japan); Suwa, T.; Kobayashi, N.; Iino, K.; Yamamoto, Y.; Igarashi, H. [Nippon Sanso K.K., Tokyo (Japan)

    1996-09-01

    This metal melting system is a process to efficiently melt and regenerate scraps of aluminum, copper and iron by utilizing high-temperature energy obtained from pulverized coal-oxygen combustion. The process is intended to utilize coal in place of petroleum for reduced fuel cost. Joint studies have been carried out as a subsidy operation of the Agency of Natural Resources and Energy with a schedule of six years starting fiscal 1992. Development tests are being performed using a 5-ton/ch pilot plant facility since fiscal 1995 after having gone through experiments using a 1-ton/ch bench scale furnace. This paper reports the results obtained to date. Using the pilot plant facility, fiscal 1995 has achieved the initial target values, such as thermal efficiency of 55% or higher, and yield of 96% or higher for non-ferrous metals and 94% or higher for iron. The melting behavior in the furnace has improved the thermal efficiency as a whole by retaining the conditions in the preheating step for an extended period of time. The thermal efficiency has been improved better than with the bench furnace as a result of upscaling effect. 9 figs., 3 tabs.

  7. Combustion of droplets and sprays

    Science.gov (United States)

    Eigenbrod, Christian; Sattelmayer, Thomas; Bäßler, Stefan; Mauss, Fabian; Meisl, Jürgen; Oomens, Bas; Rackwitz, Leif; Tait, Nigel; Angelberger, Christian; Eilts, Peter; Magnusson, Ingemar; Lauvergne, Romain; Tatschl, Reinhard

    2005-10-01

    The combustion of liquid hydrocarbon fuels in internal combustion engines and gas turbines for energy production and aircraft propulsion is intrinsically tied to the formation of pollutants. Apart from aiming for the highest combustion efficiencies in order to lower the operational costs and the emission of CO2, the reduction of poisonous and environmentally harmful exhaust constituents is a challenging task for scientists and engineers. The most prominent pollutants are soot, identified to trigger respiratory diseases and cancer, and nitric oxides such as NO and NO2, which promote the formation of ozone affecting the cardiovascular system when released in the lower atmosphere. Soot and nitric oxides are greenhouse pollutants in the upper atmosphere. Even though only 2-3% of the anthropogenic emission of nitric oxides are contributed by aircraft, it is the only emission at high altitudes. Unfortunately, it has the greatest impact on climate there and it does not matter whether the fuels are fossil or, in the future, biomass.

  8. Spying on spontaneous combustion

    Energy Technology Data Exchange (ETDEWEB)

    1994-11-01

    The British Coal Technical Services and Research Executive (TSRE) has carried out a project to investigate potential applications of fibre optic based distributed temperature sensing (DTS) technology within a mining environment. The objective was to determine whether DTS could identify and locate spontaneous combustion earlier than conventional systems. The trials took place in a British mine from April to September 1992 and from August to November 1993 using a commercially available system from York Sensors Ltd. Results indicate that DTS is capable of very sensitive temperature monitoring, revealing sub-degree thermal trends resulting from various activities and local heatings. DTS has several prospective mining applications, e.g. monitoring known hot spots, investigating ventilation and heat flow through mine workings. The trials show that the system can be installed, calibrated, operated and maintained by relatively inexperienced personnel. 1 photo.

  9. Material and system for catalytic reduction of nitrogen oxide in an exhaust stream of a combustion process

    Science.gov (United States)

    Gardner, Timothy J.; Lott, Stephen E.; Lockwood, Steven J.; McLaughlin, Linda I.

    1998-01-01

    A catalytic material of activated hydrous metal oxide doped with platinum, palladium, or a combination of these, and optionally containing an alkali or alkaline earth metal, that is effective for NO.sub.X reduction in an oxidizing exhaust stream from a combustion process is disclosed. A device for reduction of nitrogen oxides in an exhaust stream, particularly an automotive exhaust stream, the device having a substrate coated with the activated noble-metal doped hydrous metal oxide of the invention is also provided.

  10. Light Duty Efficient, Clean Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Donald Stanton

    2010-12-31

    Cummins has successfully completed the Light Duty Efficient Clean Combustion (LDECC) cooperative program with DoE. This program was established in 2007 in support of the Department of Energy's Vehicles Technologies Advanced Combustion and Emissions Control initiative to remove critical barriers to the commercialization of advanced, high efficiency, emissions compliant internal combustion (IC) engines for light duty vehicles. Work in this area expanded the fundamental knowledge of engine combustion to new regimes and advanced the knowledge of fuel requirements for these diesel engines to realize their full potential. All of the following objectives were met with fuel efficiency improvement targets exceeded: (1) Improve light duty vehicle (5000 lb. test weight) fuel efficiency by 10.5% over today's state-of-the-art diesel engine on the FTP city drive cycle; (2) Develop and design an advanced combustion system plus aftertreatment system that synergistically meets Tier 2 Bin 5 NOx and PM emissions standards while demonstrating the efficiency improvements; (3) Maintain power density comparable to that of current conventional engines for the applicable vehicle class; and (4) Evaluate different fuel components and ensure combustion system compatibility with commercially available biofuels. Key accomplishments include: (1) A 25% improvement in fuel efficiency was achieved with the advanced LDECC engine equipped with a novel SCR aftertreatment system compared to the 10.5% target; (2) An 11% improvement in fuel efficiency was achieved with the advanced LDECC engine and no NOx aftertreamtent system; (3) Tier 2 Bin 5 and SFTP II emissions regulations were met with the advanced LDECC engine equipped with a novel SCR aftertreatment system; (4) Tier 2 Bin 5 emissions regulations were met with the advanced LDECC engine and no NOx aftertreatment, but SFTP II emissions regulations were not met for the US06 test cycle - Additional technical barriers exist for the no NOx

  11. DIAGNOSIS OF FAILURE OF COMBUSTION IN THE COMBUSTION CHAMBER WITH A THERMOVISION EQUIPMENT

    Directory of Open Access Journals (Sweden)

    S. V. Vorobiev

    2014-01-01

    Full Text Available The use of thermovision technology to diagnose failure of the combustion flame test tube of the main combustion chamber gas turbine engine is deal with in the article. Join the thermal radiation of the jet of combustion products and the internal elements was carried out using short-wave thermovision system AGA-782 with spectral spectral filters in several ranges from 3.2 to 5.6 microns. Thermovision is mounted on the axis of the flame tube. The output signal was recorded and processed on a computer in real time, allowing monitor the combustion process and the thermal state of the object during the experiment.

  12. Combustion modeling in internal combustion engines

    Science.gov (United States)

    Zeleznik, F. J.

    1976-01-01

    The fundamental assumptions of the Blizard and Keck combustion model for internal combustion engines are examined and a generalization of that model is derived. The most significant feature of the model is that it permits the occurrence of unburned hydrocarbons in the thermodynamic-kinetic modeling of exhaust gases. The general formulas are evaluated in two specific cases that are likely to be significant in the applications of the model.

  13. Boiler using combustible fluid

    Science.gov (United States)

    Baumgartner, H.; Meier, J.G.

    1974-07-03

    A fluid fuel boiler is described comprising a combustion chamber, a cover on the combustion chamber having an opening for introducing a combustion-supporting gaseous fluid through said openings, means to impart rotation to the gaseous fluid about an axis of the combustion chamber, a burner for introducing a fluid fuel into the chamber mixed with the gaseous fluid for combustion thereof, the cover having a generally frustro-conical configuration diverging from the opening toward the interior of the chamber at an angle of between 15/sup 0/ and 55/sup 0/; means defining said combustion chamber having means defining a plurality of axial hot gas flow paths from a downstream portion of the combustion chamber to flow hot gases into an upstream portion of the combustion chamber, and means for diverting some of the hot gas flow along paths in a direction circumferentially of the combustion chamber, with the latter paths being immersed in the water flow path thereby to improve heat transfer and terminating in a gas outlet, the combustion chamber comprising at least one modular element, joined axially to the frustro-conical cover and coaxial therewith. The modular element comprises an inner ring and means of defining the circumferential, radial, and spiral flow paths of the hot gases.

  14. Generalised two-dimensional correlation analysis of the Co, Ce, and Pd mixed oxide catalytic systems for methane combustion using in situ infrared spectroscopy.

    Science.gov (United States)

    Chlebda, Damian K; Jodłowski, Przemysław J; Jędrzejczyk, Roman J; Łojewska, Joanna

    2018-03-05

    The process of methane combustion over the surface of a catalyst is still not fully understood. The identification of the reaction path and the intermediates created during catalysis is crucial for understanding the transformation of methane molecules. Two-dimensional (2D) correlation spectroscopy was engaged as a tool for the quantitative analysis of a series of temperature-dependent infrared spectra registered in situ during methane combustion. The prepared samples of catalysts were based on a Co, Pd and Ce mixed oxide adsorbed on an aluminium oxide layer deposited on kanthal steel. The registered spectra were transformed into 2D synchronous and asynchronous contour maps. The sequential order of spectral intensity changes was determined, and the resolution enhancement of overlapping IR bands by 2D correlation was demonstrated. The changes in the bands' intensity and information about band position can be correlated with a specific bond, and thus, the possible process intermediates can be identified. The 2DCoS analysis proved to be a powerful tool for band enhancement and revealed the changes occurring within the analysed catalyst systems as responses to increased temperature. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Lump wood combustion process

    Science.gov (United States)

    Kubesa, Petr; Horák, Jiří; Branc, Michal; Krpec, Kamil; Hopan, František; Koloničný, Jan; Ochodek, Tadeáš; Drastichová, Vendula; Martiník, Lubomír; Malcho, Milan

    2014-08-01

    The article deals with the combustion process for lump wood in low-power fireplaces (units to dozens of kW). Such a combustion process is cyclical in its nature, and what combustion facility users are most interested in is the frequency, at which fuel needs to be stoked to the fireplace. The paper defines the basic terms such as burnout curve and burning rate curve, which are closely related to the stocking frequency. The fuel burning rate is directly dependent on the immediate thermal power of the fireplace. This is also related to the temperature achieved in the fireplace, magnitude of flue gas losses and the ability to generate conditions favouring the full burnout of the fuel's combustible component, which, at once ensures the minimum production of combustible pollutants. Another part of the paper describes experiments conducted in traditional fireplaces with a grate, at which well-dried lump wood was combusted.

  16. DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS-FIRED COMBUSTION SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Glenn C. England; Stephanie Wien; Mingchih O. Chang

    2002-08-01

    This report provides results from the first year of this three-year project to develop dilution measurement technology for characterizing PM2.5 (particles with aerodynamic diameter smaller than 2.5 micrometers) and precursor emissions from stationary combustion sources used in oil, gas and power generation operations. Detailed emission rate and chemical speciation test results for a refinery gas-fired process heater and plans for cogeneration gas turbine tests and pilot-scale tests are presented. Tests were performed using a research dilution sampling apparatus and traditional EPA methods to compare PM2.5 mass and chemical speciation. Test plans are presented for a gas turbine facility that will be tested in the fourth quarter of 2002. A preliminary approach for pilot-scale tests is presented that will help define design constraints for a new dilution sampler design that is smaller, lighter, and less costly to use.

  17. Investigation of Deposit Formation Mechanisms for Engine In-cylinder Combustion and Exhaust Systems Using Quantitative Analysis and Sustainability Study

    Science.gov (United States)

    Ye, Z.; Meng, Q.; Mohamadian, H. P.; Wang, J. T.; Chen, L.; Zhu, L.

    2007-06-01

    The formation of SI engine combustion deposits is a complex phenomenon which depends on various factors of fuel, oil, additives, and engine. The goal of this study is to examine the effects of operating conditions, gasoline, lubricating oil, and additives on deposit formation. Both an experimental investigation and theoretical analysis are conducted on a single cylinder engine. As a result, the impact of deposits on engine performance and exhaust emissions (HC, NO x ) has been indicated. Using samples from a cylinder head and exhaust pipe as well as switching gases via the dual-gas method (N2, O2), the deposit formation mechanism is thoroughly investigated via the thermogravity analysis approach, where the roles of organic, inorganic, and volatile components of fuel, additives, and oil on deposit formation are identified from thermogravity curves. Sustainable feedback control design is then proposed for potential emission control and performance optimization

  18. Demonstration of oxygen-enriched combustion system on a light-duty vehicle to reduce cold-start emissions

    Energy Technology Data Exchange (ETDEWEB)

    Sekar, R.; Poola, R.B.

    1997-08-01

    The oxygen content in the ambient air drawn by combustion engines can be increased by polymer membranes. The authors have previously demonstrated that 23 to 25% (concentration by volume) oxygen-enriched intake air can reduce hydrocarbons (HC), carbon monoxide (CO), air toxics, and ozone-forming potential (OFP) from flexible-fueled vehicles (FFVs) that use gasoline or M85. When oxygen-enriched air was used only during the initial start-up and warm-up periods, the emission levels of all three regulated pollutants [CO, nonmethane hydrocarbons (NMHC), and NO{sub x}] were lower than the U.S. EPA Tier II (year 2004) standards (without adjusting for catalyst deterioration factors). In the present work, an air separation membrane module was installed on the intake of a 2.5-L FFV and tested at idle and free acceleration to demonstrate the oxygen-enrichment concept for initial start-up and warm-up periods. A bench-scale, test set-up was developed to evaluate the air separation membrane characteristics for engine applications. On the basis of prototype bench tests and from vehicle tests, the additional power requirements and module size for operation of the membrane during the initial period of the cold-phase, FTP-75 cycle were evaluated. A prototype membrane module (27 in. long, 3 in. in diameter) supplying about 23% oxygen-enriched air in the engine intake only during the initial start-up and warm-up periods of a 2.5-L FFV requires additional power (blower) of less than one horsepower. With advances in air separation membranes to develop compact modules, oxygen enrichment of combustion air has the potential of becoming a more practical technique for controlling exhaust emissions from light-duty vehicles.

  19. Combustion Byproducts Recycling Consortium

    Energy Technology Data Exchange (ETDEWEB)

    Paul Ziemkiewicz; Tamara Vandivort; Debra Pflughoeft-Hassett; Y. Paul Chugh; James Hower

    2008-08-31

    Ashlines: To promote and support the commercially viable and environmentally sound recycling of coal combustion byproducts for productive uses through scientific research, development, and field testing.

  20. Simulation of liquid propellant rocket engine combustion instabilities

    Science.gov (United States)

    Ventrice, M. B.; Fang, J. C.; Purdy, K. R.

    1979-01-01

    A simulation technique for studying the high frequency combustion instabilities of liquid propellant rocket engines has been developed and used to investigate various aspects of instability phenomena. Of importance was investigation of the significance of the method of coupling the combustion and the gas dynamics of the system. Two coupling processes were studied: linear response of the combustion process to pressure fluctuations, and the nature of the resulting instabilities; and nonlinear response of the combustion process to velocity fluctuations, and the nature of the resulting instabilities. For the combustion model studied, nonlinear (velocity) coupling was found to more closely characterize liquid propellant instabilities.

  1. Novel combustion concepts for sustainable energy development

    CERN Document Server

    Agarwal, Avinash K; Gupta, Ashwani K; Aggarwal, Suresh K; Kushari, Abhijit

    2014-01-01

    This book comprises research studies of novel work on combustion for sustainable energy development. It offers an insight into a few viable novel technologies for improved, efficient and sustainable utilization of combustion-based energy production using both fossil and bio fuels. Special emphasis is placed on micro-scale combustion systems that offer new challenges and opportunities. The book is divided into five sections, with chapters from 3-4 leading experts forming the core of each section. The book should prove useful to a variety of readers, including students, researchers, and professionals.

  2. Rapid Deployment of Rich Catalytic Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Richard S. Tuthill

    2004-06-10

    The overall objective of this research under the Turbines Program is the deployment of fuel flexible rich catalytic combustion technology into high-pressure ratio industrial gas turbines. The resulting combustion systems will provide fuel flexibility for gas turbines to burn coal derived synthesis gas or natural gas and achieve NO{sub x} emissions of 2 ppmvd or less (at 15 percent O{sub 2}), cost effectively. This advance will signify a major step towards environmentally friendly electric power generation and coal-based energy independence for the United States. Under Phase 1 of the Program, Pratt & Whitney (P&W) performed a system integration study of rich catalytic combustion in a small high-pressure ratio industrial gas turbine with a silo combustion system that is easily scalable to a larger multi-chamber gas turbine system. An implementation plan for this technology also was studied. The principal achievement of the Phase 1 effort was the sizing of the catalytic module in a manner which allowed a single reactor (rather than multiple reactors) to be used by the combustion system, a conclusion regarding the amount of air that should be allocated to the reaction zone to achieve low emissions, definition of a combustion staging strategy to achieve low emissions, and mechanical integration of a Ceramic Matrix Composite (CMC) combustor liner with the catalytic module.

  3. Equipment concept design and development plans for microgravity science and applications research on space station: Combustion tunnel, laser diagnostic system, advanced modular furnace, integrated electronics laboratory

    Science.gov (United States)

    Uhran, M. L.; Youngblood, W. W.; Georgekutty, T.; Fiske, M. R.; Wear, W. O.

    1986-01-01

    Taking advantage of the microgravity environment of space NASA has initiated the preliminary design of a permanently manned space station that will support technological advances in process science and stimulate the development of new and improved materials having applications across the commercial spectrum. Previous studies have been performed to define from the researcher's perspective, the requirements for laboratory equipment to accommodate microgravity experiments on the space station. Functional requirements for the identified experimental apparatus and support equipment were determined. From these hardware requirements, several items were selected for concept designs and subsequent formulation of development plans. This report documents the concept designs and development plans for two items of experiment apparatus - the Combustion Tunnel and the Advanced Modular Furnace, and two items of support equipment the Laser Diagnostic System and the Integrated Electronics Laboratory. For each concept design, key technology developments were identified that are required to enable or enhance the development of the respective hardware.

  4. Generation of rotary vibrations in internal combustion engines with elastically coupled electric power systems; Erzeugung von verbrennungsmotorischen Drehschwingungen mit elastisch gekoppelten elektrischen Antrieben

    Energy Technology Data Exchange (ETDEWEB)

    Falkenstein, Jens Werner [Rostock Univ. (Germany). Inst. fuer Antriebstechnik und Mechatronik

    2004-07-01

    The design of motor car powertrains requires simulations as well as prototype tests. For the simulations, prototype parameters must be identified on test rigs, simulation results must be verified, and life tests must be carried out. This necessitates realistic and reproducible excitation of vibrations. Thee book describes the development and construction of a test rig which, with the aid of electric power systems, induces rotary vibrations like those which may occur in internal combustion engines due to gas forces and unbalanced mass forces. In combination with excess resonance, the test stand achieves high dynamics with average rotary momenta up to 600 Nm. The development process is documented, from test stand design with specially developed servo-engines to the control hardware to modelling, control element design, and commissioning. (orig.)

  5. Combustion synthesis in the Ni–Al–Nb ternary system: A Time-Resolved X-ray Diffraction study

    Directory of Open Access Journals (Sweden)

    Alexander E. Sytschev

    Full Text Available Combustion synthesis of intermetallics, using the thermal explosion mode, in the Ni-Al-Nb ternary system is presented, with a 40:40:20 atomic ratio. The kinetic pathway is determined using Time-Resolved X-ray Diffraction, with a time-step resolution of 1 s and demonstrated a first formation of the B2 NiAl structure followed by progressive dissolution of Nb to yield NiAlNb intermetallic Laves phase, representing 35 w% of the final product. SEM observations show a double dendritic (coarse and fine microstructure, resulting from eutectic crystallization. Due to a high cooling rate, Nb dissolution is not complete at the surface, and yields slightly more complex microstructure, including the Ni2AlNb Geissler phase, the (Ni,Al2Nb Laves phase, and (Ni, Al7Nb6.

  6. Structure, Stability and Emissions of Lean Direct Injection Combustion, including a Novel Multi-Point LDI System for NOx Reduction

    Science.gov (United States)

    Villalva Gomez, Rodrigo

    Experimental research on Lean Direct Injection (LDI) combustors for gas turbine applications is presented. LDI combustion is an alternative to lean premixed combustion which has the potential of equivalent reduction of oxides of nitrogen (NOx) emissions and of peak combustor exit temperatures, but without some drawbacks of premixed combustors, such as flashback and autoignition. Simultaneous observations of the velocity field and reaction zone of an LDI swirl-stabilized combustor with a mixing tube at atmospheric conditions, with the goal of studying the flame stabilization mechanism, are shown. The flame was consistently anchored at the shear layer formed by the high-speed reactants exiting the mixing tube and the low speed recirculation region. Individual image analysis of the location of the tip of the recirculation zone and tip of the reaction region confirmed previously observed trends, but showed that calculation of the distance between these two points for corresponding image pairs yields results no different than when calculated from random image pairs. This most likely indicates a lag in the anchoring of the flame to changes in the recirculation zone, coupled with significant stochastic variation. An alternate LDI approach, multi-point LDI (MLDI), is also tested experimentally. A single large fuel nozzle is replaced by multiple small fuel nozzles to improve atomization and reduce the total volume of the high-temperature, low velocity recirculation zones, reducing NOx formation. The combustor researched employs a novel staged approach to allow good performance across a wide range of conditions by using a combination of nozzle types optimized to various power settings. The combustor has three independent fuel circuits referenced as pilot, intermediate, and outer. Emissions measurements, OH* chemiluminescence imaging, and thermoacoustic instability studies were run in a pressurized combustion facility at pressures from 2.0 to 5.3 bar. Combustor performance

  7. 一种内燃发动机点火方法和系统\\ud An internal combustion engine ignition system and method

    OpenAIRE

    Li, Yun; Chen, W; Sun, F; Yun Li

    2013-01-01

    本发明公开了一种内燃发动机点火方法和系统,其中,内燃发动机点火系统包括:电磁波源、耦合装置、汽缸和控制单元,其中,控制单元,监测当前的内燃发动机转速,并在达到所述内燃发动机转速的点火提前角度时通知电磁波源;电磁波源,产生一处于所述汽缸固有频率的范围内的固定频率的电磁波;耦合装置,将所述电磁波输入所述汽缸;耦合装置的探入汽缸的火花塞接口的部分和汽缸,构成谐振腔,使所述电磁波在汽缸内被谐振放大后产生的电场强度大于发生点火的临界电场强度。本发明能够在不改变现有内燃发动机结构的前提下,替代现有内燃发动机高压火花点火系统的火花塞将电磁波有效地耦合入汽缸内,并大大提高射频和电磁波点火的成功机率。\\ud The present invention discloses a method and an internal combustion engine ignition system wherein the internal combustion engine ignition system comprising: a source of electromagnetic waves, the c...

  8. Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Ojeda, William de

    2010-07-31

    The project which extended from November 2005 to May of 2010 demonstrated the application of Low Temperature Combustion (LTC) with engine out NOx levels of 0.2 g/bhp-hr throughout the program target load of 12.6bar BMEP. The project showed that the range of loads could be extended to 16.5bar BMEP, therefore matching the reference lug line of the base 2007 MY Navistar 6.4L V8 engine. Results showed that the application of LTC provided a dramatic improvement over engine out emissions when compared to the base engine. Furthermore LTC improved thermal efficiency by over 5% from the base production engine when using the steady state 13 mode composite test as a benchmark. The key enablers included improvements in the air, fuel injection, and cooling systems made in Phases I and II. The outcome was the product of a careful integration of each component under an intelligent control system. The engine hardware provided the conditions to support LTC and the controller provided the necessary robustness for a stable combustion. Phase III provided a detailed account on the injection strategy used to meet the high load requirements. During this phase, the control strategy was implemented in a production automotive grade ECU to perform cycle-by-cycle combustion feedback on each of the engine cylinders. The control interacted on a cycle base with the injection system and with the Turbo-EGR systems according to their respective time constants. The result was a unique system that could, first, help optimize the combustion system and maintain high efficiency, and secondly, extend the steady state results to the transient mode of operation. The engine was upgraded in Phase IV with a Variable Valve Actuation system and a hybrid EGR loop. The impact of the more versatile EGR loop did not provide significant advantages, however the application of VVA proved to be an enabler to further extend the operation of LTC and gain considerable benefits in fuel economy and soot reduction. Finally

  9. Lectures on combustion theory

    Energy Technology Data Exchange (ETDEWEB)

    Burstein, S.Z.; Lax, P.D.; Sod, G.A. (eds.)

    1978-09-01

    Eleven lectures are presented on mathematical aspects of combustion: fluid dynamics, deflagrations and detonations, chemical kinetics, gas flows, combustion instability, flame spread above solids, spark ignition engines, burning rate of coal particles and hydrocarbon oxidation. Separate abstracts were prepared for three of the lectures. (DLC)

  10. Strobes: An Oscillatory Combustion

    NARCIS (Netherlands)

    Corbel, J.M.L.|info:eu-repo/dai/nl/341356034; van Lingen, J.N.J.|info:eu-repo/dai/nl/311441769; Zevenbergen, J.F.; Gijzeman, O.L.J.|info:eu-repo/dai/nl/073464708; Meijerink, A.|info:eu-repo/dai/nl/075044986

    2012-01-01

    Strobe compositions belong to the class of solid combustions. They are mixtures of powdered ingredients. When ignited, the combustion front evolves in an oscillatory fashion, and flashes of light are produced by intermittence. They have fascinated many scientists since their discovery at the

  11. Strobes: An oscillatory combustion

    NARCIS (Netherlands)

    Corbel, J.M.L.; Lingen, J.N.J. van; Zevenbergen, J.F.; Gijzeman, O.L.J.; Meijerink, A.

    2012-01-01

    Strobe compositions belong to the class of solid combustions. They are mixtures of powdered ingredients. When ignited, the combustion front evolves in an oscillatory fashion, and flashes of light are produced by intermittence. They have fascinated many scientists since their discovery at the

  12. Rocket Combustion Chamber Coating

    Science.gov (United States)

    Holmes, Richard R. (Inventor); McKechnie, Timothy N. (Inventor)

    2001-01-01

    A coating with the ability to protect (1) the inside wall (i.e., lining) of a rocket engine combustion chamber and (2) parts of other apparatuses that utilize or are exposed to combustive or high temperature environments. The novelty of this invention lies in the manner a protective coating is embedded into the lining.

  13. Gaseous emissions from waste combustion.

    Science.gov (United States)

    Werther, Joachim

    2007-06-18

    An overview is given on methods and technologies for limiting the gaseous emissions from waste combustion. With the guideline 2000/76/EC recent European legislation has set stringent limits not only for the mono-combustion of waste in specialized incineration plants but also for co-combustion in coal-fired power plants. With increased awareness of environmental issues and stepwise decrease of emission limits and inclusion of more and more substances into the network of regulations a multitude of emission abatement methods and technologies have been developed over the last decades. The result is the state-of-the-art waste incinerator with a number of specialized process steps for the individual components in the flue gas. The present work highlights some new developments which can be summarized under the common goal of reducing the costs of flue gas treatment by applying systems which combine the treatment of several noxious substances in one reactor or by taking new, simpler routes instead of the previously used complicated ones or - in the case of flue gas desulphurisation - by reducing the amount of limestone consumption. Cost reduction is also the driving force for new processes of conditioning of nonhomogenous waste before combustion. Pyrolysis or gasification is used for chemical conditioning whereas physical conditioning means comminution, classification and sorting processes. Conditioning yields a fuel which can be used in power plants either as a co-fuel or a mono-fuel and which will burn there under much better controlled conditions and therefore with less emissions than the nonhomogeneous waste in a conventional waste incinerator. Also for cost reasons, co-combustion of wastes in coal-fired power stations is strongly pressing into the market. Recent investigations reveal that the co-firing of waste can also have beneficial effects on the operating behavior of the boiler and on the gaseous emissions.

  14. Demonstration of Active Combustion Control

    Science.gov (United States)

    Lovett, Jeffrey A.; Teerlinck, Karen A.; Cohen, Jeffrey M.

    2008-01-01

    The primary objective of this effort was to demonstrate active control of combustion instabilities in a direct-injection gas turbine combustor that accurately simulates engine operating conditions and reproduces an engine-type instability. This report documents the second phase of a two-phase effort. The first phase involved the analysis of an instability observed in a developmental aeroengine and the design of a single-nozzle test rig to replicate that phenomenon. This was successfully completed in 2001 and is documented in the Phase I report. This second phase was directed toward demonstration of active control strategies to mitigate this instability and thereby demonstrate the viability of active control for aircraft engine combustors. This involved development of high-speed actuator technology, testing and analysis of how the actuation system was integrated with the combustion system, control algorithm development, and demonstration testing in the single-nozzle test rig. A 30 percent reduction in the amplitude of the high-frequency (570 Hz) instability was achieved using actuation systems and control algorithms developed within this effort. Even larger reductions were shown with a low-frequency (270 Hz) instability. This represents a unique achievement in the development and practical demonstration of active combustion control systems for gas turbine applications.

  15. PDF Modeling of Turbulent Combustion

    National Research Council Canada - National Science Library

    Pope, Stephen B

    2006-01-01

    .... The PDF approach to turbulent combustion has the advantages of fully representing the turbulent fluctuations of species and temperature, and of allowing realistic combustion chemistry to be implemented...

  16. Integrated Physics-based Modeling and Experiments for Improved Prediction of Combustion Dynamics in Low-Emission Systems

    Science.gov (United States)

    Anderson, William E.; Lucht, Robert P.; Mongia, Hukam

    2015-01-01

    Concurrent simulation and experiment was undertaken to assess the ability of a hybrid RANS-LES model to predict combustion dynamics in a single-element lean direct-inject (LDI) combustor showing self-excited instabilities. High frequency pressure modes produced by Fourier and modal decomposition analysis were compared quantitatively, and trends with equivalence ratio and inlet temperature were compared qualitatively. High frequency OH PLIF and PIV measurements were also taken. Submodels for chemical kinetics and primary and secondary atomization were also tested against the measured behavior. For a point-wise comparison, the amplitudes matched within a factor of two. The dependence on equivalence ratio was matched. Preliminary results from simulation using an 18-reaction kinetics model indicated instability amplitudes closer to measurement. Analysis of the simulations suggested a band of modes around 1400 Hz were due to a vortex bubble breakdown and a band of modes around 6 kHz were due to a precessing vortex core hydrodynamic instability. The primary needs are directly coupled and validated ab initio models of the atomizer free surface flow and the primary atomization processes, and more detailed study of the coupling between the 3D swirling flow and the local thermoacoustics in the diverging venturi section.

  17. Residential combustion venting failure. A systems approach. Final technical report. Project 5: Remedial measures for wood-burning fireplaces

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    This report is a review of remedial measures available for avoiding or correcting combustion venting problems in wood-burning fireplaces and included on account of field tests of airtight doors with direct air supply and of a fireplace spillage advisor. It appeared that properly designed, truly airtight doors are effective in isolating fireplaces from the house indoor pressure regime and that this remedial measure does not affect the fire safety of the fireplace. It was also found that the detection of smoke particles was effective when the fire was hot and flaming, but not during the smoldering stage of the fire; on the other hand, the detection of carbon monoxide was not effective during the hot and flaming stage, but was effective during the smoldering stage. It is, therefore, necessary, for a fireplace spillage advisor to incorporate both technologies. The design and optimum location of a fireplace spillage advisor are discussed. A list of fires due to burning solid fuel in British Columbia during the year of 1985 in given, together with their assumed causes. 6 figs., 2 tabs.

  18. Fuels and Combustion

    KAUST Repository

    Johansson, Bengt

    2016-08-17

    This chapter discusses the combustion processes and the link to the fuel properties that are suitable for them. It describes the basic three concepts, including spark ignition (SI) and compression ignition (CI), and homogeneous charge compression ignition (HCCI). The fuel used in a CI engine is vastly different from that in an SI engine. In an SI engine, the fuel should sustain high pressure and temperature without autoignition. Apart from the dominating SI and CI engines, it is also possible to operate with a type of combustion: autoignition. With HCCI, the fuel and air are fully premixed before combustion as in the SI engine, but combustion is started by the increased pressure and temperature during the compression stroke. Apart from the three combustion processes, there are also a few combined or intermediate concepts, such as Spark-Assisted Compression Ignition (SACI). Those concepts are discussed in terms of the requirements of fuel properties.

  19. Real-Time Combustion Controls and Diagnostics Sensors (CCADS)

    Energy Technology Data Exchange (ETDEWEB)

    Thornton, J.D.; Richard, G.A.; Dodrill, K.A.; Nutter, R.S. Jr; Straub, D.

    2005-05-03

    The present invention is directed to an apparatus for the monitoring of the combustion process within a combustion system. The apparatus comprises; a combustion system, a means for supplying fuel and an oxidizer, a device for igniting the fuel and oxidizer in order to initiate combustion, and a sensor for determining the current conducted by the combustion process. The combustion system comprises a fuel nozzle and an outer shell attached to the combustion nozzle. The outer shell defines a combustion chamber. Preferably the nozzle is a lean premix fuel nozzle (LPN). Fuel and an oxidizer are provided to the fuel nozzle at separate rates. The fuel and oxidizer are ignited. A sensor positioned within the combustion system comprising at least two electrodes in spaced-apart relationship from one another. At least a portion of the combustion process or flame is between the first and second electrodes. A voltage is applied between the first and second electrodes and the magnitude of resulting current between the first and second electrodes is determined.

  20. Real time identification of the internal combustion engine combustion parameters based on the vibration velocity signal

    Science.gov (United States)

    Zhao, Xiuliang; Cheng, Yong; Wang, Limei; Ji, Shaobo

    2017-03-01

    Accurate combustion parameters are the foundations of effective closed-loop control of engine combustion process. Some combustion parameters, including the start of combustion, the location of peak pressure, the maximum pressure rise rate and its location, can be identified from the engine block vibration signals. These signals often include non-combustion related contributions, which limit the prompt acquisition of the combustion parameters computationally. The main component in these non-combustion related contributions is considered to be caused by the reciprocating inertia force excitation (RIFE) of engine crank train. A mathematical model is established to describe the response of the RIFE. The parameters of the model are recognized with a pattern recognition algorithm, and the response of the RIFE is predicted and then the related contributions are removed from the measured vibration velocity signals. The combustion parameters are extracted from the feature points of the renovated vibration velocity signals. There are angle deviations between the feature points in the vibration velocity signals and those in the cylinder pressure signals. For the start of combustion, a system bias is adopted to correct the deviation and the error bound of the predicted parameters is within 1.1°. To predict the location of the maximum pressure rise rate and the location of the peak pressure, algorithms based on the proportion of high frequency components in the vibration velocity signals are introduced. Tests results show that the two parameters are able to be predicted within 0.7° and 0.8° error bound respectively. The increase from the knee point preceding the peak value point to the peak value in the vibration velocity signals is used to predict the value of the maximum pressure rise rate. Finally, a monitoring frame work is inferred to realize the combustion parameters prediction. Satisfactory prediction for combustion parameters in successive cycles is achieved, which

  1. Integrated dry NO{sub x}/SO{sub 2} emissions control system low-NO{sub x} combustion system retrofit test report. Test report, August 6--October 29, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.A.; Muzio, L.J. [Fossil Energy Research Corp., Laguna Hills, CA (United States); Hunt, T. [Public Service Co. of Colorado, Denver, CO (United States)

    1993-06-01

    The DOE sponsored Integrated Dry NO{sub x}/SO{sub 2} Emissions Control System program, which is a Clean Coal Technology M demonstration, is being conducted by Public Service Company of Colorado. The test site is Arapahoe Generating Station Unit 4, which is a 100 MWe, down-fired utility boiler burning a low-sulfur Western coal. The project goal is to demonstrate up to 70 percent reductions in NO{sub x} and SO{sub 2} emissions through the integration of: (1) down-fired low-NO{sub x} burners with overfire air; (2) Selective NonCatalytic Reduction (SNCR) for additional NO{sub x} removal; and (3) dry sorbent injection and duct humidification for SO{sub 2} removal. The effectiveness of the integrated system on a high-sulfur coal will also be investigated. This report documents the third phase of the test program, where the performance of the retrofit low-NO{sub x} combustion system is compared to that of the original combustion system. This third test phase was comprised of an optimization of the operating conditions and settings for the burners and overfire air ports, followed by an investigation of the performance of the low-NO{sub x} combustion system as a function of various operating parameters. These parameters included boiler load, excess air level, overfire air flow rate and number of mills in service. In addition, emissions under normal load following operation were compared to those collected during the optimization and parametric performance tests under baseloaded conditions. The low-NO{sub x} combustion system retrofit resulted in NO{sub x} reductions of 63 to 69 percent, depending on boiler load. The majority of the NO{sub x} reduction was obtained with the low-NO{sub x} burners, as it was shown that the overfire air system provided little additional NO{sub x} reduction for a fixed excess air level. CO emissions and flyash carbon levels did not increase as a result of the retrofit.

  2. System analyse cellulose ethanol in combines - Combustion characterisation of lignin from cellulose based ethanol production; Systemanalys foer cellulosabaserad etanol i kombinat - Foerbraenningskarakterisering av lignin fraan cellulosabaserad etanolproduktion

    Energy Technology Data Exchange (ETDEWEB)

    Lindstedt, Jan; Wingren, Anders; Magnusson, Staffan; Wiinikka, Henrik; Westbom, Urban; Lidman, Marcus; Groenberg, Carola

    2012-02-15

    In this work 3 different hydrolysed lignin fractions produced from Sugarcane Bagasse, Spruce and Wheat Straw were burned in a 150 kW horizontal furnace equipped with a powder burner to assess the combustion behaviour of hydrolysed lignin fuels. The combustion experiments showed that the feeding properties of all three lignin fractions were better compared to ordinary wood powder

  3. Quantifying of the Thermal Dynamic Characteristics of the Combustion System for Underground Coal Fire and its Impact on Environment in Xinjiang region, China

    Science.gov (United States)

    ZENG, Qiang; Tiyip, Tashpolat; Wuttke, Manfred; NIE, Jing; PU, Yan

    2015-04-01

    Underground Coal fire (UCF) is one disaster associated with coal mining activities around the world. The UCF not only burns up the coal reservoir, but also causes serious environmental problems, such as the pollution to air, the damage to soils, and the contamination to surface and underground water and consequently the health problem to human beings. In the present paper, the authors attempts to quantify the thermal dynamic characteristics of the combustion system for UCF and its impact on environment by modeling, including delineating the physical boundary of UCF zone, modeling of the capacity of the oxygen supply to UCF, modeling the intensity of heat generation from UCF and modeling the process of heat transfer within UCF and its surrounding environment. From this research, results were obtained as follows: First of all, based on the rock control theory, a model was proposed to depict the physical boundary of UCF zone which is important for coal fire research. Secondly, with analyzing the characteristics of air and smoke flow within UCF zone, an air/smoke flow model was proposed and consequently a method was put forward to calculate the capacity of oxygen supply to the UCF. Thirdly, with analyzing the characteristics of coal combustion within UCF zone, a method of calculating the intensity of heat generation from UCF, i.e., the heat source models, was established. Heat transfer with UCF zone includes the heat conductivity within UCF zone, the heat dissipation by radiation from the surface of fire zone, and the heat dissipation by convection as well as the heat loss taken away by mass transport. The authors also made an effort to depict the process of heat transfer by quantitative methods. Finally, an example of Shuixigou coal fire was given to illustrate parts of above models. Further more, UCF's impact on environment, such as the heavy metals contamination to surface soil of fire zone and the characteristics of gaseous pollutants emission from the UCF also was

  4. Preliminary assessment of the health and environmental impacts of fluidized-bed combustion of coal as applied to electrical utility systems

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-02-01

    The objective of this study was to assess the health and environmental impacts of fluidized-bed combustion of coal (FBC), specifically as applied to base-load generation of electrical energy by utilities. The public health impacts of Fluidized-Bed Combustion (FBC) plants are expected to be quite similar to those for Low Sulfur Coal (LSC) and Flue Gas Desulfurization (FGD) plants because all appear to be able to meet Federal emission standards; however, there are emissions not covered by standards. Hydrocarbon emissions are higher and trace element emissions are lower for FBC than for conventional technologies. For FBC, based on an analytical model and a single emission data point, the polycyclic organic material decreases the anticipated lifespan of the highly exposed public very slightly. Added health protection due to lower trace element emissions is not known. Although there is a large quantity of solid wastes from the generating plant, the environmental impact of the FBC technology due to solid residue appears lower than for FGD, where sludge management requires larger land areas and presents problems due to the environmentally noxious calcium sulfite in the waste. Fixing the sludge may become a requirement that increases the cost of wet-limestone FGD but makes that system more acceptable. The potential for aquatic or terrestrial impacts from hydrocarbon emissions is low. If application of AFBC technology increases the use of local high-sulfur coals to the detriment of western low-sulfur coal, a sociological benefit could accrue to the FBC (or FGD) technology, because impacts caused by western boom towns would decrease. The infrastructure of areas that mine high-sulfur coal in the Midwest are better equipped to handle increased mining than the West.

  5. Radiative transfer modelling in combusting systems using discrete ordinates method on three-dimensional unstructured grids; Modelisation des transferts radiatifs en combustion par methode aux ordonnees discretes sur des maillages non structures tridimensionnels

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, D.

    2004-04-01

    The prediction of pollutant species such as soots and NO{sub x} emissions and lifetime of the walls in a combustion chamber is strongly dependant on heat transfer by radiation at high temperatures. This work deals with the development of a code based on the Discrete Ordinates Method (DOM) aiming at providing radiative source terms and wall fluxes with a good compromise between cpu time and accuracy. Radiative heat transfers are calculated using the unstructured grids defined by the Computational Fluid Dynamics (CFD) codes. The spectral properties of the combustion gases are taken into account by a statistical narrow bands correlated-k model (SNB-ck). Various types of angular quadrature are tested and three different spatial differencing schemes were integrated and compared. The validation tests show the limit at strong optical thicknesses of the finite volume approximation used the Discrete Ordinates Method. The first calculations performed on LES solutions are presented, it provides instantaneous radiative source terms and wall heat fluxes. Those results represent a first step towards radiation/combustion coupling. (author)

  6. Construction of a power plant with prototype DLN combustion turbines

    Energy Technology Data Exchange (ETDEWEB)

    Wilkinson, M.L. [CSW Energy, Dallas, TX (United States); Drummond, L.J. [Zurn NEPCO, Redmond, WA (United States)

    1996-12-31

    Design and construction of a power plant is always a difficult process and this is especially true when the main keystone, the combustion turbine engine, is being modified by the manufacturer resulting in numerous changes in the design interfaces. The development of the design and construction of the Orange Cogeneration Facility has been in parallel with major modification of the LM6000 to DLE technology (a Dry Low NO{sub x} combustion system). The Dry Low NO{sub x} Combustion System for a combustion turbine offered a means to reduce water usage, lower Zero Liquid Discharge System operating costs and reduce emissions to meet Florida Department of Environmental Protection requirements. This development was successfully accomplished by Owner, EPC contractor and Combustion Turbine Manufacturer by maintaining flexibility in the design and construction while the design interfaces and performance of the combustion turbines were being finalized.

  7. Microscale combustion and power generation

    CERN Document Server

    Cadou, Christopher; Ju, Yiguang

    2014-01-01

    Recent advances in microfabrication technologies have enabled the development of entirely new classes of small-scale devices with applications in fields ranging from biomedicine, to wireless communication and computing, to reconnaissance, and to augmentation of human function. In many cases, however, what these devices can actually accomplish is limited by the low energy density of their energy storage and conversion systems. This breakthrough book brings together in one place the information necessary to develop the high energy density combustion-based power sources that will enable many of these devices to realize their full potential. Engineers and scientists working in energy-related fields will find: An overview of the fundamental physics and phenomena of microscale combustion; Presentations of the latest modeling and simulation techniques for gasphase and catalytic micro-reactors; The latest results from experiments in small-scale liquid film, microtube, and porous combustors, micro-thrusters, a...

  8. Modeling the internal combustion engine

    Science.gov (United States)

    Zeleznik, F. J.; Mcbride, B. J.

    1985-01-01

    A flexible and computationally economical model of the internal combustion engine was developed for use on large digital computer systems. It is based on a system of ordinary differential equations for cylinder-averaged properties. The computer program is capable of multicycle calculations, with some parameters varying from cycle to cycle, and has restart capabilities. It can accommodate a broad spectrum of reactants, permits changes in physical properties, and offers a wide selection of alternative modeling functions without any reprogramming. It readily adapts to the amount of information available in a particular case because the model is in fact a hierarchy of five models. The models range from a simple model requiring only thermodynamic properties to a complex model demanding full combustion kinetics, transport properties, and poppet valve flow characteristics. Among its many features the model includes heat transfer, valve timing, supercharging, motoring, finite burning rates, cycle-to-cycle variations in air-fuel ratio, humid air, residual and recirculated exhaust gas, and full combustion kinetics.

  9. 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.

  10. Atmospheric fluidized bed combustion advanced system concepts applicable to small industrial and commercial markets. Topical report, Level 2

    Energy Technology Data Exchange (ETDEWEB)

    Ake, T.R.; Dixit, V.B.; Mongeon, R.K.

    1992-09-01

    As part of an overall strategy to promote FBC coal combustion and to improve the marketability of the eastern coals, the US Department of Energy`s Morgantown Energy Research Center awarded a three level contract to Riley Stoker Corporation to develop advanced Multi Solids Fluidized Bed (MSFB) boiler designs. The first level of this contract targeted the small package boiler (10,000--50,000 lb/hr steam) and industrial size boiler (75,000--150,000 lb/hr steam) markets. Two representative sizes, 30,000 lb/hr and 110,000 lb/hr of steam, were selected for the two categories for a detailed technical and economic evaluation. Technically, both the designs showed promise, however, the advanced industrial design was favored on economic considerations. It was thus selected for further study in the second level of the contract. Results of this Level-2 effort, presented in this report, consisted of testing the design concept in Riley`s 4.4 MBtu/hr pilot MSFB facility located at Riley Research Center in Worcester, Mass. The design and economics of the proof of concept facility developed in Level-1 of the contract were then revised in accordance with the findings of the pilot test program. A host site for commercial demonstration in Level-3 of the contract was also secured. It was determined that co-firing coal in combination with paper de-inking sludge will broaden the applicability of the design beyond conventional markets. International Paper (IP), the largest paper company in the world, is willing to participate in this part of the program. IP has offered its Hammermill operation at Lockhaven, Pa, site of a future paper de-inking plant, for the proof of concept installation. This plant will go in operation in 1994. It is recommended that METC proceed to the commercial demonstration of the design developed. The approach necessary to satisfy the needs of the customer while meeting the objectives of this program is presented along with a recommended plan of action.

  11. Combustion Technology Outreach

    Science.gov (United States)

    1995-01-01

    Lewis' High Speed Research (HSR) Propulsion Project Office initiated a targeted outreach effort to market combustion-related technologies developed at Lewis for the next generation of supersonic civil transport vehicles. These combustion-related innovations range from emissions measurement and reduction technologies, to diagnostics, spray technologies, NOx and SOx reduction of burners, noise reduction, sensors, and fuel-injection technologies. The Ohio Aerospace Institute and the Great Lakes Industrial Technology Center joined forces to assist Lewis' HSR Office in this outreach activity. From a database of thousands of nonaerospace firms considered likely to be interested in Lewis' combustion and emission-related technologies, the outreach team selected 41 companies to contact. The selected companies represent oil-gas refineries, vehicle/parts suppliers, and manufacturers of residential furnaces, power turbines, nonautomobile engines, and diesel internal combustion engines.

  12. JANNAF 35th Combustion Subcommittee Meeting. Volume 1

    Science.gov (United States)

    Fry, Ronald S. (Editor); Gannaway, Mary T. (Editor); Rognan, Melanie (Editor)

    1998-01-01

    Volume 1, the first of two volumes is a compilation of 63 unclassified/unlimited distribution technical papers presented at the 35th meeting of the Joint Army-Navy-NASA-Air Force (JANNAF) Combustion Subcommittee (CS) held jointly with the 17th Propulsion Systems Hazards Subcommittee (PSHS) and Airbreathing Propulsion Subcommittee (APS). The meeting was held on 7-11 December 1998 at Raytheon Systems Company and the Marriott Hotel, Tucson, AZ. Topics covered include solid gun propellant processing, ignition and combustion, charge concepts, barrel erosion and flash, gun interior ballistics, kinetics and molecular modeling, ETC gun modeling, simulation and diagnostics, and liquid gun propellant combustion; solid rocket motor propellant combustion, combustion instability fundamentals, motor instability, and measurement techniques; and liquid and hybrid rocket combustion.

  13. Review of the systems analysis of interactions between the thermal, lubricant, and combustion processes of diesel engines

    OpenAIRE

    Burke, R. D.; Brace, C. J.; Hawley, J. G.; Pegg, I.

    2010-01-01

    A review of technologies surrounding the thermal management system of the modern diesel engine with increased attention on fuel consumption is presented. A system-based approach has been adopted, looking at the interaction with other key systems. Previous innovation has aimed at reducing the power consumption of the cooling system or incorporating different cooling strategies and improving the engine warm-up rate for improved fuel consumption by higher operating temperatures. Electrical pumps...

  14. Starting apparatus for internal combustion engines

    Science.gov (United States)

    Dyches, G.M.; Dudar, A.M.

    1995-01-01

    This report is a patent description for a system to start an internal combustion engine. Remote starting and starting by hearing impaired persons are addressed. The system monitors the amount of current being drawn by the starter motor to determine when the engine is started. When the engine is started the system automatically deactivates the starter motor. Five figures are included.

  15. Sandia Combustion Research Program

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, S.C.; Palmer, R.E.; Montana, C.A. (eds.)

    1988-01-01

    During the late 1970s, in response to a national energy crisis, Sandia proposed to the US Department of Energy (DOE) a new, ambitious program in combustion research. Shortly thereafter, the Combustion Research Facility (CRF) was established at Sandia's Livermore location. Designated a ''user facility,'' the charter of the CRF was to develop and maintain special-purpose resources to support a nationwide initiative-involving US inventories, industry, and national laboratories--to improve our understanding and control of combustion. This report includes descriptions several research projects which have been simulated by working groups and involve the on-site participation of industry scientists. DOE's Industry Technology Fellowship program, supported through the Office of Energy Research, has been instrumental in the success of some of these joint efforts. The remainder of this report presents results of calendar year 1988, separated thematically into eleven categories. Referred journal articles appearing in print during 1988 and selected other publications are included at the end of Section 11. Our traditional'' research activities--combustion chemistry, reacting flows, diagnostics, engine and coal combustion--have been supplemented by a new effort aimed at understanding combustion-related issues in the management of toxic and hazardous materials.

  16. Transient combustion in hybrid rockets

    Science.gov (United States)

    Karabeyoglu, Mustafa Arif

    1998-09-01

    Hybrid rockets regained interest recently as an alternative chemical propulsion system due to their advantages over the solid and liquid systems that are currently in use. Development efforts on hybrids revealed two important problem areas: (1) low frequency instabilities and (2) slow transient response. Both of these are closely related to the transient behavior which is a poorly understood aspect of hybrid operation. This thesis is mainly involved with a theoretical study of transient combustion in hybrid rockets. We follow the methodology of identifying and modeling the subsystems of the motor such as the thermal lags in the solid, boundary layer combustion and chamber gasdynamics from a dynamic point of view. We begin with the thermal lag in the solid which yield the regression rate for any given wall heat flux variation. Interesting phenomena such as overshooting during throttling and the amplification and phase lead regions in the frequency domain are discovered. Later we develop a quasi-steady transient hybrid combustion model supported with time delays for the boundary layer processes. This is integrated with the thermal lag system to obtain the thermal combustion (TC) coupled response. The TC coupled system with positive delays generated low frequency instabilities. The scaling of the instabilities are in good agreement with actual motor test data. Finally, we formulate a gasdynamic model for the hybrid chamber which successfully resolves the filling/emptying and longitudinal acoustic behavior of the motor. The TC coupled system is later integrated to the gasdynamic model to obtain the overall response (TCG coupled system) of gaseous oxidizer motors with stiff feed systems. Low frequency instabilities were also encountered for the TCG coupled system. Apart from the transient investigations, the regression rate behavior of liquefying hybrid propellants such as solid cryogenic materials are also studied. The theory is based on the possibility of enhancement

  17. Numerical Simulation Method for Combustion in a Oxyhydrogen Rocket Motor

    OpenAIRE

    Taki, Shiro; Fujiwara, Toshitaka; 滝, 史郎; 藤原, 俊隆

    1984-01-01

    Numerical simulations of unsteady phenomena in the combustion chamber of an oxyhydrogen rocket motor were made in an attempt to develop a computer code for use in investigating such phenomena as vibrating combustion. The combustion in this system is controlled by diffusion, the effect of which works much slower than sound or pressure waves, so that diffusions are usually solved using the implicit finite difference method for unlimited time step size caused by stability criterion. However, the...

  18. Gasification and combustion technologies of agro-residues and their application to rural electric power systems in India

    Science.gov (United States)

    Bharadwaj, Anshu

    understand the impact of co-firing on utility boilers. A detailed biomass devolatilization sub-model is also developed to study the importance of intra-particle heat and mass transport. Finally, we conduct an experimental study of the pyrolysis of rice husk. We conducted single particle experiments in a Confocal Scanning Laser Microscope (CSLM) at the Department of Material Science and Engineering, Carnegie Mellon University coupled with Scanning Electron Microscope (SEM) analysis of partially and fully combusted particles. Our results seem to indicate that the role of silica fibers is not merely to act as geometric shields for the carbon atoms. Instead there appears to be a strong and thermally resistant inter-molecular bonding that prevents carbon conversion. Therefore, it may not be possible to achieve full carbon conversion.

  19. Perspective -- Aerodynamic control of combustion

    Energy Technology Data Exchange (ETDEWEB)

    Oppenheim, A.K. [Univ. of California, Berkeley, CA (United States). Mechanical Engineering

    1993-12-01

    To do useful work, the exothermic process of combustion should be carried out in an enclosure, as is typically the case with i.c. engines -- the subject of this paper`s particular concern. To meet the requirements of high efficiency and low pollutant production, this process should be executed at a relatively low temperature -- a condition attainable by the use of lean air-fuel mixtures. For this purpose it has to be distributed in space upon multipoint initiation and kept away from the walls to minimize their detrimental effects. In principle, all this can be accomplished by a system referred to as fireball combustion that takes advantage of entrainment and spiral mixing associated with large scale vortex structures of jet plumes. As demonstrated in this paper, the success in such an endeavor depends crucially upon the utilization of the essential elements of classical aerodynamics: the properly distributed sources, expressed in terms of velocity divergences prescribed by the thermodynamic process of combustion and of the vorticity field generated by shear between the jets and the fluid into which they are injected.

  20. Theoretical studies of combustion dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, J.M. [Emory Univ., Atlanta, GA (United States)

    1993-12-01

    The basic objectives of this research program are to develop and apply theoretical techniques to fundamental dynamical processes of importance in gas-phase combustion. There are two major areas currently supported by this grant. One is reactive scattering of diatom-diatom systems, and the other is the dynamics of complex formation and decay based on L{sup 2} methods. In all of these studies, the authors focus on systems that are of interest experimentally, and for which potential energy surfaces based, at least in part, on ab initio calculations are available.

  1. New combustion, environment regulations: the answers for natural gas; Nouvelles reglementations, combustion, environnement: les reponses pour le gaz naturel

    Energy Technology Data Exchange (ETDEWEB)

    Le Peltier-Marc, A. [Gaz de France (GDF), 75 - Paris (France)

    1997-12-31

    This paper reports on the point of view from Gaz de France (GdF) company concerning the potential consequences of the use of natural gas in combustion systems with respect to the new regulations about combustion and environment. Details concerning the measures relative to the limitation of pollutants in small combustion installations (2 - 20 MW) are given (chimney height, SO{sub x}, NO{sub x} and dusts content in exhaust gases). (J.S.)

  2. Energy Analysis and Multi-Objective Optimization of an Internal Combustion Engine-Based CHP System for Heat Recovery

    Directory of Open Access Journals (Sweden)

    Abdolsaeid Ganjehkaviri

    2014-10-01

    Full Text Available A comprehensive thermodynamic study is conducted of a diesel based Combined Heat and Power (CHP system, based on a diesel engine and an Organic Rankine Cycle (ORC. Present research covers both energy and exergy analyses along with a multi-objective optimization. In order to determine the irreversibilities in each component of the CHP system and assess the system performance, a complete parametric study is performed to investigate the effects of major design parameters and operating conditions on the system’s performance. The main contribution of the current research study is to conduct both exergy and multi-objective optimization of a system using different working fluid for low-grade heat recovery. In order to conduct the evolutionary based optimization, two objective functions are considered in the optimization; namely the system exergy efficiency, and the total cost rate of the system, which is a combination of the cost associated with environmental impact and the purchase cost of each component. Therefore, in the optimization approach, the overall cycle exergy efficiency is maximized satisfying several constraints while the total cost rate of the system is minimized. To provide a better understanding of the system under study, the Pareto frontier is shown for multi-objective optimization and also an equation is derived to fit the optimized point. In addition, a closed form relationship between exergy efficiency and total cost rate is derived.

  3. Assessment of an atmospheric fluidized-bed coal-combustion gas-turbine cogeneration system for industrial application

    Energy Technology Data Exchange (ETDEWEB)

    Graves, R. L.; Holcomb, R. S.; Tallackson, J. R.

    1979-10-01

    This study was initiated to provide information on the future potential industrial market for a cogeneration system consisting of a fluidized-bed coal combustor coupled to a gas-turbine (Brayton cycle) power system that uses air as the working fluid. In assessing the potential applications for the system, the process heat energy consumption by industry is identified, with special detail included on the six most energy-intensive industries. The potential impact on the nation's oil and natural gas consumption that would result from wide-spread utilization of coal for process heat is also estimated. The fraction of industrial process heat that the system could feasibly satisfy from a thermodynamic viewpoint is estimated, and the performance (potential fuel efficiency and heat/power ratio) of the atmospheric fluidized-bed gas-turbine system is calculated. Also treated are several specific case studies of industries in which the system could be incorporated. Major parameters are specified, and flow sheets are derived for systems that would satisfy the heat and power requirements of the process or industry. The overall fuel utilization efficiency, thermal power rating, and potential number of installations are specified for these case studies. The findings of the study indicate that there is a sizable potential market for the system, with over 1000 possible installations disclosed after reviewing only 8 specific industries from 6 major Standard Industrial Classification (SIC) groups. The potential displacement of oil and gas by coal in process heating is shown to be about 1.60 m/sup 3//sec (870,000 bbl/d) of oil and 4590 m/sup 3//sec (14.0 billion ft/sup 3//d) of natural gas for all industries combined. Continued development of the fluidized-bed coal combustor and power system is recommended so that this potential may be at least partially realized.

  4. Sounding Solid Combustibles: Non-premixed Flame Sound Synthesis for Different Solid Combustibles.

    Science.gov (United States)

    Yin, Qiang; Liu, Shiguang

    2016-12-21

    With the rapidly growing VR industry, in recent years, more and more attention has been paid for fire sound synthesis. However, previous methods usually ignore the influences of the different solid combustibles, leading to unrealistic sounding results. This paper proposes SSC (sounding solid combustibles), which is a new recording-driven non-premixed flame sound synthesis framework accounting for different solid combustibles. SSC consists of three components: combustion noise, vortex noise and popping sounds. The popping sounds are the keys to distinguish the differences of solid combustibles. To improve the quality of fire sound, we extract the features of popping sounds from the real fire sound examples based on modified Empirical Mode Decomposition (EMD) method. Unlike previous methods, we take both direct combustion noise and vortex noise into account because the fire model is non-premixed flame. In our method, we also greatly resolve the synchronization problem during blending the three components of SSC. Due to the introduction of the popping sounds, it is easy to distinguish the fire sounds of different solid combustibles by our method, with great potential in practical applications such as games, VR system, etc. Various experiments and comparisons are presented to validate our method.

  5. Model of the containment building of Almaraz NPP and the system of recombiners PARs, with the GOTHIC code, for the study of the diffusion of combustible gases; Modelo del edificio de contencion de C.N. Almaraz y del sistema de recombinadores PARs, con el codigo GOTHIC, para el estudio de la difusion de gases combustibles

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Gonzalez, M.; Huelamo, E.; Mazrtinez, M.; Perez, J. R.

    2014-07-01

    This paper presents the analysis of distribution of gases within the containment building carried out a simulation model with the code Thermo hydraulic GOTHIC, which has been evaluated based on passive autocatalytic recombiners gas control system. The model considers scenarios of severe accident with specific conditions that produce the most hydrogen generation rates. Intended to verify the effectiveness of the control system of gas expected to be installed in the Almaraz Nuclear power plant so that the number and location of recombiners equipment meets its function of preventing the formation of explosive atmospheres which impairs the integrity of the containment, reducing and limiting the concentration of combustible gases during the postulated accident. (Author)

  6. Rates of fuel discharge as affected by the design of fuel-injection systems for internal-combustion engines

    Science.gov (United States)

    Gelalles, A G; Marsh, E T

    1933-01-01

    Using the method of weighing fuel collected in a receiver during a definite interval of the injection period, rates of discharge were determined, and the effects noted, when various changes were made in a fuel-injection system. The injection system consisted primarily of a by-pass controlled fuel pump and an automatic injection valve. The variables of the system studied were the pump speed, pump-throttle setting, discharge-orifice diameter, injection-valve opening and closing pressures, and injection-tube length and diameter.

  7. Unified system for holographic measurement in fluid and solid mechanics: application of the system to volumetric flow measurement in an internal combustion engine

    Science.gov (United States)

    Chan, Victor S. S.; Barnhart, Donald H.; Garner, Colin P.; Halliwell, Neil A.; Coupland, Jeremy M.

    1999-10-01

    This paper reports holographic measurements of full-field 3D flows inside a production geometry 4-stoke internal combustion engine with extensive optical access through both the cylinder wall and the piston crown. The seeded flow is recorda at two instants as a reflection hologram of high numerical aperture. A purpose built holographic camera using a phase conjugate holographic optical element is used to compensate for the gross aberrations caused by imaging through a thick walled, glass cylinder. Fiber-optic, conjugate recognition and subsequent correlation of the complex amplitude recorded by the hologram facilitates sub- wavelength measurement of particle displacement without directional ambiguity. Preliminary measurements of the flow field within the cylinder at the bottom of the induction stroke are discussed. The results clearly show the potential of this technique to extract 3D velocity information in hostile environments.

  8. Distinctive features of the intrachamber instability of combustion in liquid-propellant rocket engines

    Science.gov (United States)

    Gotsulenko, V. V.

    2008-09-01

    Self-oscillations and certain of their regularities determined by solution of a degenerate system of differential equations that is used in considering combustion instability in combustion chambers of liquid-propellant rocket engines are modeled mathematically.

  9. Laser-based techniques applied to the diagnostic of combustion systems; Applicazioni delle tecniche laser alla diagnosica dei sistemi di combustione

    Energy Technology Data Exchange (ETDEWEB)

    Migliavacca, G.; Lopinto, P.; Parodi, E. [Stazione Sperimentale per i Combustibili, San Donato Milanese, MI (Italy)

    2001-04-01

    The design and the optimisation of modern and efficient combustion systems need detailed studies and in situ investigations of the complex dynamics of the chemical and fluido-dynamic processes involved. The optical techniques, based on the application of laser radiation, like Laser Induced Fluorescence (LIF), Raman spectroscopy and scattering techniques are particularly suited for this purpose, since they supply non-intrusive and multiparametric measurements having a high spatial and temporal resolution. This paper presents a general review of the most promising techniques in the field, along with a brief summary of their possible application. [Italian] La realizzazione e l'ottimizzazione di moderni ed efficienti sistemi di combustione richiede una investigazione in situ ed un dettagliato studio della complessa dinamica dei processi chimici e fluidodinamici che in essi hanno luogo. Le tecniche ottiche, fondate sull'utilizzo della radiazione laser, come quelle LIF (Laser Induced Fluorescence), la spettroscopia Raman e quelle basate sui processi di scattering sono particolarmente adatta a questo scopo giacche' forniscono misure non intrusive e multiparametriche con una alta risoluzione spaziale e temporale. Nella presenta rassegna viene presentata una panoramica generale delle tecniche maggiormente promettenti e diffuse in questo campo, insieme ad un breve compendio delle loro possibili applicazioni.

  10. Uma Análise da Demanda por Combustíveis Através do Modelo Almost Ideal Demand System para Pernambuco

    Directory of Open Access Journals (Sweden)

    Edilberto Tiago de Almeida

    Full Text Available Resumo: O mercado de combustíveis tem sido amplamente estudado sob várias perspectivas, desde a questão da assimetria e transmissão de preços, formação de cartéis, dinâmica de preços atrelada às flutuações na economia internacional, sistemas de demanda, entre outras. Neste sentido, este artigo tem como objetivo estimar um sistema de demanda para gasolina comum, etanol hidratado e óleo diesel via modelo (LA-AIDS Linear Approximation Almost Ideal Demand System com dados de séries temporais trimestrais para o período de 2001 a 2015 para o estado de Pernambuco. As estimações foram feitas por meio do método (SUR Seemingly Unrelated Regressions. Os resultados encontrados são semelhantes aos observados na literatura, no sentido em que apontam para a inelasticidade-preço da demanda da gasolina e diesel, o que é esperado dada a essencialidade dos bens. Também foi possível verificar que a demanda por etanol é elástica por ter elasticidade-preço marshalliana maior que um em valor absoluto, convergindo para os resultados já encontrados em outros estudos.

  11. Environmentally conscious coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Hickmott, D.D.; Brown, L.F.; Currier, R.P. [and others

    1997-08-01

    This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of this project was to evaluate the environmental impacts of home-scale coal combustion on the Navajo Reservation and develop strategies to reduce adverse health effects associated with home-scale coal combustion. Principal accomplishments of this project were: (1) determination of the metal and gaseous emissions of a representative stove on the Navajo Reservation; (2) recognition of cyclic gaseous emissions in combustion in home-scale combustors; (3) `back of the envelope` calculation that home-scale coal combustion may impact Navajo health; and (4) identification that improved coal stoves require the ability to burn diverse feedstocks (coal, wood, biomass). Ultimately the results of Navajo home-scale coal combustion studies will be extended to the Developing World, particularly China, where a significant number (> 150 million) of households continue to heat their homes with low-grade coal.

  12. Combustion and regulation; Combustion et reglementation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This conference was organized after the publication of the French by-law no 2010 relative to combustion installations and to the abatement of atmospheric pollution. Five topics were discussed during the conference: the new regulations, their content, innovations and modalities of application; the means of energy suppliers to face the new provisions and their schedule; the manufacturers proposals for existing installations and the new equipments; the administration control; and the impact of the new measures on exploitation and engineering. Twenty papers and 2 journal articles are reported in these proceedings. (J.S.)

  13. Combustible structural composites and methods of forming combustible structural composites

    Science.gov (United States)

    Daniels, Michael A.; Heaps, Ronald J.; Steffler, Eric D.; Swank, W. David

    2013-04-02

    Combustible structural composites and methods of forming same are disclosed. In an embodiment, a combustible structural composite includes combustible material comprising a fuel metal and a metal oxide. The fuel metal is present in the combustible material at a weight ratio from 1:9 to 1:1 of the fuel metal to the metal oxide. The fuel metal and the metal oxide are capable of exothermically reacting upon application of energy at or above a threshold value to support self-sustaining combustion of the combustible material within the combustible structural composite. Structural-reinforcing fibers are present in the composite at a weight ratio from 1:20 to 10:1 of the structural-reinforcing fibers to the combustible material. Other embodiments and aspects are disclosed.

  14. Development of a low NO{sub x} combustion system for a roof-fired utility boiler

    Energy Technology Data Exchange (ETDEWEB)

    Bionda, J.P.; Glickert, R.W. [Energy Systems Associates, Pittsburgh, PA (United States); Hallo, A.; Gretz, G.F. [Duquesne Light Co., Pittsburgh, PA (United States)

    1995-12-31

    Duquesne Light Company operates three roof-fired utility boilers at its Elrama Power Station in Elrama, Pennsylvania. These units are required to comply with the requirements of the Clean Air Act Amendments. Specifically, they need to reduce the emission rate of nitric oxide (NO{sub x}) to less than 0.50 lb/MBtu by May 31, 1995. Energy Systems Associates (ESA) was contracted to design a low NO{sub x} retrofit system for these units. Preliminary testing was performed to establish a baseline for NO{sub x}, CO and flyash carbon. A computational furnace model was utilized to evaluate various low NO{sub x} burner and separated overfire air (SOFA) designs. ``Proof of Concept`` field testing validated the low NO{sub x} burner design effectiveness. The SOFA system design was finalized and installed. This paper describes the development, design, and results of the Elrama low NO{sub x} retrofit system. The results of this project should be of interest to utilities evaluating low NO{sub x} retrofit technologies for roof-fired boilers.

  15. Pulsed atmospheric fluidized bed combustion

    Energy Technology Data Exchange (ETDEWEB)

    1989-11-01

    In order to verify the technical feasibility of the MTCI Pulsed Atmospheric Fluidized Bed Combustor technology, a laboratory-scale system was designed, built and tested. Important aspects of the operational and performance parameters of the system were established experimentally. A considerable amount of the effort was invested in the initial task of constructing an AFBC that would represent a reasonable baseline against which the performance of the PAFBC could be compared. A summary comparison of the performance and emissions data from the MTCI 2 ft {times} 2 ft facility (AFBC and PAFBC modes) with those from conventional BFBC (taller freeboard and recycle operation) and circulating fluidized bed combustion (CFBC) units is given in Table ES-1. The comparison is for typical high-volatile bituminous coals and sorbents of average reactivity. The values indicated for BFBC and CFBC were based on published information. The AFBC unit that was designed to act as a baseline for the comparison was indeed representative of the larger units even at the smaller scale for which it was designed. The PAFBC mode exhibited superior performance in relation to the AFBC mode. The higher combustion efficiency translates into reduced coal consumption and lower system operating cost; the improvement in sulfur capture implies less sorbent requirement and waste generation and in turn lower operating cost; lower NO{sub x} and CO emissions mean ease of site permitting; and greater steam-generation rate translates into less heat exchange surface area and reduced capital cost. Also, the PAFBC performance generally surpasses those of conventional BFBC, is comparable to CFBC in combustion and NO{sub x} emissions, and is better than CFBC in sulfur capture and CO emissions even at the scaled-down size used for the experimental feasibility tests.

  16. Experimental investigation of hydraulic effects of two-stage fuel injection on fuel-injection systems and diesel combustion in a high-speed optical common-rail diesel engine

    OpenAIRE

    Herfatmanesh, MR; Zhao, H

    2014-01-01

    In order to meet the ever more stringent emission standards, significant efforts have been devoted to the research and development of internal combustion engines. The requirements for more efficient and responsive diesel engines have led to the introduction and implementation of multiple injection strategies. However, the effects of such injection modes on the hydraulic systems, such as the high-pressure pipes and fuel injectors, must be thoroughly examined and compensated for since the combu...

  17. Internal combustion engine

    Science.gov (United States)

    Baker, Quentin A.; Mecredy, Henry E.; O'Neal, Glenn B.

    1991-01-01

    An improved engine is provided that more efficiently consumes difficult fuels such as coal slurries or powdered coal. The engine includes a precombustion chamber having a portion thereof formed by an ignition plug. The precombustion chamber is arranged so that when the piston is proximate the head, the precombustion chamber is sealed from the main cylinder or the main combustion chamber and when the piston is remote from the head, the precombustion chamber and main combustion chamber are in communication. The time for burning of fuel in the precombustion chamber can be regulated by the distance required to move the piston from the top dead center position to the position wherein the precombustion chamber and main combustion chamber are in communication.

  18. System to solve three designs of the fuel management; Sistema para resolver tres disenos de la administracion de combustible

    Energy Technology Data Exchange (ETDEWEB)

    Castillo M, J. A.; Ortiz S, J. J.; Montes T, J. L.; Perusquia del C, R. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Marinez R, R., E-mail: alejandro.castillo@inin.gob.mx [Universidad Autonoma de Campeche, Av. Agustin Melgar s/n, Col. Buenavista, 24039 San Francisco de Campeche, Campeche (Mexico)

    2015-09-15

    In this paper preliminary results are presented, obtained with the development of a computer system that resolves three stages of the nuclear fuel management, which are: the axial and radial designs of fuel, as well as the design of nuclear fuel reloads. The novelty of the system is that the solution is obtained solving the 3 mentioned stages, in coupled form. For this, heuristic techniques are used for each stage, in each one of these has a function objective that is applied to particular problems, but in all cases the obtained partial results are used as input data for the next stage. The heuristic techniques that were used to solve the coupled problem are: tabu search, neural networks and a hybrid between the scatter search and path re linking. The system applies an iterative process from the design of a fuel cell to the reload design, since are preliminary results the reload is designed using the operation strategy Haling type. In each one of the stages nuclear parameters inherent to the design are monitored. The results so far show the advantage of solving the problem in a coupled manner, even when a large amount of computer resources is used. (Author)

  19. Shape-Controlled TiCx Particles Fabricated by Combustion Synthesis in the Cu-Ti-C System

    Directory of Open Access Journals (Sweden)

    Dongdong Zhang

    2017-07-01

    Full Text Available TiCx particle-reinforced Cu-matrix composites were prepared in the Cu-Ti-C system by thermal explosion and hot press. Extracted TiCx particles with various shapes of in situ TiCx particles in the Cu-Ti-C system were observed through the Field Emission Scanning Electron Microscope (FESEM. It was found that octahedral and close-to-spherical, spherical or cubic TiCx could be fabricated by changing the C/Ti molar ratio and Cu content. Then, the effect of the C/Ti molar ratio and constituent element concentrations on the shape of in situ TiCx particles was determined: the shape of TiCx particles is octahedral at a C/Ti ratio of 0.4–0.6 with the presence of 70 vol% Cu; or spherical and close-to-spherical at 0.8–1.0 with the presence of 70 vol% Cu; or cubic at C/Ti ratios ≥1.0 with the presence of Cu from 80 vol%–90 vol% and even at C/Ti ratios >1.0 with the presence of 70 vol% Cu. The shape-controlled synthesis of TiCx particles in the Cu-Ti-C system is realized.

  20. Analysis of the internal temperature of the combustion chamber of a compact system of co-generation; Analise das temperaturas internas da camara de combustao de um sistema compacto de co-geracao

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, Joao B.F. [Universidade de Fortaleza (UNIFOR), CE (Brazil)], email: furlan@unifor.br; Couto, Heraldo S. [Instituto Nacional de Pesquisas Espaciais (INPE), Cachoeira Paulista, SP (Brazil)], email: heraldo@lcp.inpe.br; Holanda, Carlos A.M. de [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Engenharia Metalurgica e de Materiais], email: almir@metalmat.ufc.br

    2008-07-01

    Nowadays, the energy deficit represents one of the biggest governmental challenges, since there is still a great number of communities living in areas without electricity energy; and thus without access to electro-electronic equipment such as television, refrigerators, computers. The main focus of this work is to present the possibility of electricity energy generation in conjunction with the frozen or hot water production in for places without electricity transmission nets or even any type of alternative power plants. The system is based on the standard air cycle called Brayton cycle composed of a turbo-compressor model 4LGZ from BorgWarner, a combustion chamber, a power turbine, a heat exchanger, a water-ammonia chiller, a 5.0 kV A generator, and a command panel for automation and distribution of energy. This system that uses natural gas or LPG, will supply electric energy from the generator, hot water from the heat exchange with the gases of combustion, and water frozen from chiller using as the hot source the gases proceeding from the power system. The prototype is already being tested and the first results obtained are excellent. In this paper, we analyze the internal combustion chamber temperatures. (author)