Abstract Booklet 2006 - Swanson School of Engineering - University ...

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27-3 Studies in Pyrolysis and Combustion of Indian Coals Using Thermogravimetric Analyzer Preeti Aghalayam, Anil Khadse, Chinmay Ghoroi, Sanjay Mahajani, IIT Bombay, INDIA Experiments are performed to study the pyrolysis and combustion reactions for Indian coals using a Thermogravimetric Analyzer (NETZSCH STA 409 PC/PG). Burning profiles and volatile release profiles are obtained at various heating rates, in both air and inert atmospheres, from 25 to 1000°C for three coal samples. Peak temperatures are obtained and activation energies are calculated. The activation energies are in the range 68.49-100.29 kJ/mol at a heating rate of 10°C /min, 66-88.13 kJ/mol at 20°C /min and 52.74-74.93 kJ/mol at 30°C /min, for the combustion reaction. For pyrolysis, activation energies are in the range 34.79-147.99 kJ/mol at 10°C /min, 38.40-166.74 kJ/mol at 20°C /min and 36.72-167.46 kJ/mol at 30°C /min. 27-4 Study of the Effect of FeCl 3 on the Ignition Point of Coal Qiaowen Yang, Dongyao Xu, Wei Li, Aiguo Cheng, Jia Cao, Liying Wang, China University of Mining & Technology, P.R. CHINA The combustion supporting alternate agent of three coals was selected by Thermal Gravity Analysis (TG) in this paper, it has been found that FeCl 3 plays great role on reducing the ignition point of Guangxi Liang-coal, and FeCl 3 could effectively reduce the ignition point of Xinwen raw coal and Guangxi An-coal also. It also stated that FeCl 3 has a good combustion supporting action on the coal. At the same time, the relationship of FeCl 3 amount and the ignition point of coal were inspected; the optimum amount of FeCl 3 could be got. We initially probed into the combustion supporting mechanism of FeCl 3 , during combustion, the combustion supporting action of FeCl 3 was the results of common action of chloride and iron in chemicals; The combustion supporting action of FeCl 3 was individually achieved by reducing the ignition point of Volatile and Fixed Carbon. 27-5 Modeling and Simulation of Single Coal Particle Combustion Anil Samale, Arvind Latey, College of Engineering Pune, INDIA In the present study, a mathematical model to describe the combustion of single coal particle is developed by incorporating improvement in the existing models available in the literature. This model couples the heat transfer equation with the chemical kinetics equations. The combustion rate has been simulated by considering the first order reaction (C+O 2 = CO 2 ). The dependence of the convective heat transfer coefficient on Nusselt number is incorporated in this model. A finite volume method using a TDMA scheme is used for solving heat transfer equation and Runge-Kutta fourth order method for the chemical kinetics equations. The model equation is solved for the spherical coal particle of equivalent radius ranging from 0.00005 m to 0.0001m and temperature ranging from 300 K to 1000 K. The simulated results obtained by using the present model are in excellent agreement with experimental data, much better than the agreement with earlier model reported in the literature. Simulation results capture expected qualitative trends in nature. SESSION 28 ENVIRONMENTAL CONTROL TECHNOLOGIES: MERCURY OXIDATION/CATALYSTS 28-1 Mercury Transformation Reactions on Model Fly Ashes Sukh Sidhu, Patanjali Varanasi, University of Dayton Research Institute, USA From results of our previous mercury oxidation study which was conducted using four different Ohio coal fly ashes, it was observed that the chemical composition of surfaces plays a very important role in mercury oxidation reactions. To further understand mercury oxidation and its dependence on the chemical composition of fly ashes, a series of experiments were conducted using model fly ashes. These model fly ashes were prepared using flame soot as carbon source and iron oxide as metal oxide catalyst. Vanadia supported on titania was also used as a catalyst in order to compare mercury oxidation observed on the surface of model fly ashes with that on SCR catalyst. To keep catalytic bed characteristic same for all surfaces the catalytic surface were dispersed on quartz wool. In all experiments, the inlet concentration of Hg 0 (g) was maintained at 47 µg/m 3 using a permeation device as the source of Hg 0 (g). All experiments were conducted using 4% O 2 in nitrogen mix as a reaction gas, and other reactants (HCl, H 2 O) were added as required. The fixed bed catalytic reactor was operated over a temperature range of 300 to 500°C. In each experiment the reactor effluent was sampled using modified Ontario-Hydro method. After each experiment, fixed beds were also analyzed for mercury. It was observed that soot is more active in mercury oxidation than vanadia/titania and iron oxide catalyst. Results also show that over the surface of metal oxide catalysts mercury oxidation is only weakly dependent on temperature. 28-2 Experimental Investigation and Theoretical Calculation on Effect of C12 on Mercury Oxidation in Coal Fire Combustion Process Wei-Ping Pan, Songgeng Li, Quanhai Wang, Yan Cao, ICSET of Western Kentucky University, USA Mercury (Hg) from coal power plants has been identified as the hazardous air pollutant of greatest public health concern. Hg in the flue gas occurs as three main forms: the gaseous elemental mercury Hg(0), the gaseous oxidized Hg(2+), and particulate mercury, Hg(p). Hg(2+) is water soluble, highly absorbable on fly ash and has a low vapor pressure. Therefore, relative to Hg(0), Hg(2+) is more effectively captured in conventional Air Pollution Control Devices (APCD) such as wet scrubbers (FGD), fabric filters (FF) and electrostatic precipitator (ESP). However, Hg(0) is firstly vaporized in the flue gas at higher temperature zone in combustor, followed by thermodynamically favored oxidation process to major occurrence of Hg(2+) through the homogeneous and the heterogeneous reaction routines at downstream flue gas pass as temperature is cooled down. Thus, identifying the mechanism of mercury oxidation in the downstream flue gas pass is very important to improve mercury emission control efficiencies by APCD in the coal-fired boilers. Based on facts that HgCl 2 is the main Hg(2+) in coal-fired combustion process, as well as enormous previous studies on Hg oxidation, it has been generally accepted that chlorine-containing species are the most important factor on the Hg(0) oxidation in coal-fired flue gas. Chlorine is evolved during coal combustion primarily as hydrochloric acid (HCl), less chance as chlorine molecule (Cl 2 ) through the Deacon reaction under fly ash available conditions. However, the possible concentration of Cl 2 is still much higher than request by the Hg oxidation process. Moreover, the flue gas chemistry may dramatically impact this oxidation process by the intermediate reactions to affect production of chlorine ion, which is more active in the Hg oxidation process. In this work, isolated effects of Cl 2 and HCl or their effects including other flue gas species on Hg oxidation under a largely varied temperature window were investigated in a special designed multi-phase flow reactor. A thermal-dynamic and kinetics calculation is used to explore the maxim Hg oxidation rate and possible reaction mechanisms. 28-3 A Theoretical Cluster Approach to Understanding Mercury Adsorption to Halogen-Embedded Activated Carbon Bihter Padak, Michael Brunetti, Jennifer Wilcox, Worcester Polytehcnic Institute, USA Ab initio methods have been employed for the modeling of activated carbon surface using a fused-benzene ring cluster approach. Oxygen functional groups have been investigated for their promotion of effective elemental mercury adsorption on the activated carbon surface sites. Lactone and carbonyl functional groups yield the highest mercury binding energies. Additionally, halogen atoms have been added to the modeled surface, and have found to increase the activated carbon’s mercury adsorption capacity. The mercury binding energies increase with the addition of the following halogen atoms, F > Cl > Br > I, with the addition of fluorine being the most promising halogen for increasing mercury adsorption. 28-4 Survey of Catalysts for Oxidation of Mercury in Flue Gas Evan J. Granite, Albert A. Presto, DOE/NETL, USA The United States Environmental Protection Agency issued a regulation in March of 2005 for the emission of mercury from coal-burning power plants. In addition, several states have also enacted legislation requiring control of mercury emissions from coalburning plants. Mercury is a neurotoxin and accumulates within the food chain. Elemental mercury is difficult to capture from a gas stream. Much of the mercury contained in power plant flue gas is in the elemental form. Elemental mercury is a semi-noble metal, is insoluble in water, and is not captured efficiently by carbon. Mercuric chloride is highly soluble in water, and is more readily removed by carbon. A catalyst that can oxidize elemental mercury to mercuric chloride (or another compound) would be of tremendous value. A catalyst would enable mercury to be captured by existing air pollution control devices (APCDs) present in coal-burning power plants. These existing APCDs include wet scrubbers for acid gas removal, as well as electrostatic precipitators (ESPs) and baghouse filters for particulate removal. The mercury oxidation catalyst can be located upstream of the appropriate APCD. Mercuric chloride is readily removed by the scrubbing solutions employed for acid gas removal. Mercuric chloride is easily removed by adsorption on unburned carbon in fly ash captured in ESPs or baghouse filters. Mercuric chloride is also sequestered by activated carbon sorbents injected upstream of an ESP or baghouse. Several materials have been proposed as catalysts for oxidation of mercury. These materials include palladium, gold, iridium, platinum, SCR catalysts, fly ash, activated carbons, Thief carbons, and halogen compounds. Previous results obtained with these catalysts are reviewed. Several mechanisms of mercury oxidation are proposed, and future research directions are suggested. Alternative catalysts and supports will be suggested, and an extensive list of references will be provided. The work presented in this manuscript was recently accepted for publication in Environmental Science & Technology. 24
28-5 A Kinetic Approach to Catalytic Oxidation of Mercury in Flue Gas Evan J. Granite, Albert A. Presto, Henry W. Pennline, Andy Karash, William J. O’Dowd, Richard A. Hargis, DOE/NETL, USA Several materials have been examined as catalysts for the oxidation of mercury in a bench-scale packed-bed reactor located at NETL. The catalysts examined include activated carbon, Thief carbons, precious metals, fly ash, and halogen compounds. Slipstreams of flue gas generated by the NETL 500-lb/hr pilot-scale combustion facility were contacted with the catalysts. An on-line continuous emissions monitor (CEM) was employed to measure elemental and oxidized mercury entering and exiting the bed. The apparent activation energy and reaction order for mercury were determined for several of the catalysts. Future research on catalyst materials will be conducted in a bench-scale packed-bed reactor employing both simulated and real flue gas streams generated on-site at NETL. The work presented in this manuscript was also accepted for publication in Energy & Fuels. SESSION 29 GAS TURBINES AND FUEL CELLS FOR SYNTHESIS GAS AND HYDROGEN APPLICATIONS – 1 29-1 Coal IGCC Turbine Technology Improvements for Carbon Free Fuels Ashok Anand, Benjamin Mancuso, Kevin Collins, Greg Wotzak, GE Energy, USA Reduction of carbon dioxide from Coal-based IGCC Power Plants is rapidly gaining increased interest in future installations. Studies have shown that IGCC technology is able to capture and remove carbon dioxide at lower economic penalty as compared to conventional pulverized coal fired steam plants. Further improvements in IGCC power plants with carbon capture, is possible though the development of specific gas turbine cycle designs that increase plant efficiency at reduced costs and emissions. The performance influence of a typical heavy-duty gas turbine’s cycle parameters on IGCC plant with carbon capture is presented. An optimization analysis method is described, which can be successfully applied to select a gas turbine cycle design to achieve plant level performance goals. 29-2 Advanced Hydrogen Turbine Development Ed Bancalari, Ihor S. Diakunchak, Pedy Chan, Siemens Power Generation, Inc., USA The Advanced Hydrogen Turbine Development Project objective is to design and develop a fuel flexible (coal derived hydrogen or syngas) advanced gas turbine for Integrated Gasification Combined Cycle (IGCC) and FutureGen type applications that meets the U.S. Department of Energy (DOE) turbine performance goals. The overall DOE Advanced Power System goal is to conduct the Research and Development necessary to produce CO 2 sequestration ready coal-based IGCC power systems with high efficiency (45-50% [HHV]), near zero emissions (< 2 ppm NO x @ 15% O 2 ) and competitive plant capital cost (< $1000/kW). DOE has awarded Siemens Power Generation a contract for Phases 1 and 2 development work. Phase 1 activities will include identification of advanced technologies required to achieve the Project goals, detailed Research & Development Implementation Plan preparation and conceptual designs for the new gas turbine components. In Phase 2, the identified concepts/technologies will be down selected and a detailed design of the gas turbine will be completed. Phase 3, which has not yet been awarded, will involve the advanced gas turbine and IGCC plant construction and validation/demonstration testing. The end objective is to validate the advanced gas turbine technology by 2015. The starting point for this development effort is the SGT6-6000G gas turbine. This gas turbine will be adapted for operation on coal and biomass derived hydrogen and syngas fuels, as well as natural gas, while achieving high performance levels and reduced capital costs. This paper describes Phase 1 activities and accomplishments in the first 9 months since the program was initiated. 29-3 Benefits to IGCC Gas Turbines of Advanced Vortex Combustion Robert Steele, Pete Baldwin, Ramgen Power Systems, USA Ramgen Power Systems is developing an Advanced Vortex Combustion (AVC) technology for combustion of hydrogen-based fuels which shows tremendous potential for increased energy efficiency and improved asset utilization. The fundamentals of the technology and the potential advantages of incorporating the AVC approach into an IGCC gas turbine will be presented. The AVC technology can be applied to the efficient and cost-effective combustion of hydrogen-based fuels with sub-3 ppmv NO x emissions while maintaining or extending simple cycle efficiencies. The AVC technology has the potential for improved turbine efficiency, lower NO x emissions, greater flame stability, high flame speed flexibility, increased durability, and reduced manufacturing costs. This approach can play an important role in the advancement of future Integrated Gasification Combined Cycle (IGCC) power plants that will require hydrogen-enriched fuel burning gas turbines. The flame speed of hydrogen-air mixture is six times higher than a natural gas-air mixture. Conventional swirl-based combustion systems 25 need customized modifications in order to manage the potential for flame flashback. The unique insensitivity of the AVC approach to high through-put velocities will reduce hardware modifications and accommodate the extremely fast burning hydrogen-based fuels. In addition, Ramgen’s AVC technology is cross-cutting and capable of delivering benefits to many of the technical areas of concern in zero-emissions combustor-based facilities including the oxy-fuel Rankine cycle system. 29-4 Catalytic Combustion for Ultra-Low NO x Hydrogen Turbines Benjamin Baird, S. Etemad, Sandeep Alvandi, William C. Pfefferle, H. Karim, Precision Combustion, Inc., USA Kenneth O. Smith, W. Nazeer, Solar Turbines, Inc., USA Precision Combustion, Inc. (PCI), under sponsorship from the U.S. Department of Energy, is further developing it’s Rich Catalytic Lean-burn (RCL®) combustion system for hydrogen fuels. Rich catalytic operation has successfully demonstrated low single digit ppm NO x and the ability to burn hydrogen fuels in 9 atmosphere subscale tests. The test data show the potential of using rich catalytic combustion for low single digit emissions. Areas of further work to commercialize this technology has been identified. PCI, in collaboration with Solar Turbines Incorporated and other gas turbine manufacturers, has a 39 month DOE Fossil Energy Turbine Technology R&D program to develop and demonstrate a low emission rich catalytic combustion system for fuel flexible ultra-low NO x megawatt-scale gas turbines that can utilize hydrogen fuel, facilitate high efficiency operation, and be installed or retrofitted into existing turbines. This paper presents the status of the rich catalytic application from the combustion point of view for MW size engine application. 29-5 Development of Turbo Machinery for a Zero CO 2 Emissions Oxy-Fuel Cycle Mohan A. Hebber, Shiv Dinkar, Juan Pablo Gutierrez, Siemens Power Generation, Inc. Jim Downs, Florida Turbine Technologies, Inc., USA In 2005 the U.S. Department of Energy-National Energy Technology Laboratory (DOE- NETL) awarded a program to Siemens Power Generation (SPG), Inc. to develop turbo machinery powered by oxy-fuel combustion, which generates near zero emissions and provides for economical CO 2 capture capability. (The combustor for this oxy-fuel cycle is to be developed separately by Clean Energy Systems (CES), Inc. of Rancho Cordova, California.). The new working fluid (a mixture of CO 2 and steam) and the desire to maximize the plant cycle efficiency pose numerous technical challenges not only in developing the turbine designs and consideration of material systems, but also in the selection of a plant cycle. The calculation of auxiliary loads for Fuel Processing Plant (gasifier), Air Separation Unit (ASU), O 2 compression, CO 2 compression, limitations on metal temperatures and other boundary conditions – all posed difficulties in arriving at cycles for further consideration. Any turbine design that depends on boundary conditions higher than the current state-of-the-art poses special challenges in the selection of materials. Initial studies indicate that materials in the turbine for the “topping” cycle may have to tolerate a Turbine Inlet Temperature (TIT) well in excess of 1500°C with CO 2 and H 2 O as working fluid. With regards to the steam turbine in the “bottoming” cycle, major challenges are anticipated in selecting materials for the turbine casing, rotor, blading, valves, sealing and bolting. Other challenges include innovative cooling techniques including, but not limited to, the development of serpentine cooling paths; development of start-up procedures and algorithms for controls and life consumption. The paper describes approaches planned to overcome the technical challenges and develop turbine designs that meet the overall objectives of the program including the efficiency goals. An overall time line is also identified for key milestones. SESSION 30 GLOBAL CLIMATE CHANGE: CO 2 CAPTURE – 2: MEMBRANES AND SOLID SORBENTS 30-1 Experimental Investigation of a Molecular Gate Membrane for Separation of Carbon Dioxide for Flue Gas James Hoffman, Henry W. Pennline, DOE/NETL, USA Shingo Kazama, Teruhiko Kai, Takayuki Kouketsu, Shigetoshi Matsui, Koichi Yamada, RITE, JAPAN Commercial-sized modules of the PAMAM dendrimer composite membrane with high CO 2 /N 2 selectivity and CO 2 permeance were developed according to the In-situ Modification (IM) method. This method utilizes the interfacial precipitation of membrane materials on the surface of porous, commercially available polysulfone (PSF) ultrafiltration hollow fiber membrane substrates. A thin layer of amphiphilic chitosan, which has a potential affinity for both hydrophobic PSF substrates and hydrophilic PAMAM dendrimers, was employed as a gutter layer directly beneath the inner surface of the substrate by the IM method. PAMAM dendrimers were then impregnated into the chitosan gutter layer to form a hybrid active layer for CO 2 separation. Permeation experiments of the PAMAM dendrimer composite membrane were carried out using a humidified mixed CO 2 / N 2 feed gas at a pressure
Page 1 and 2: TABLE OF CONTENTS Oral Sessions Pag
Page 3 and 4: 1-1 SESSION 1 GASIFICATION TECHNOLO
Page 5 and 6: The U.S. pioneered development of s
Page 7 and 8: 5-5 Enhanced Hydrogen Production wi
Page 9 and 10: derived synthesis gases employing i
Page 11 and 12: Several physical adsorbents, partic
Page 13 and 14: 13-1 SESSION 13 GASIFICATION TECHNO
Page 15 and 16: promising Clean Coal technologies u
Page 17 and 18: high selectivity (theoretically pro
Page 19 and 20: 19-3 Development of Highly Efficien
Page 21 and 22: The Aim of the project is the impro
Page 23 and 24: 24-3 Development of Fluidizable Lit
Page 25: the classical Lurgi-gasifcation pro
Page 29 and 30: turbine cycles. The models provide
Page 31 and 32: up to 290 psia and temperatures up
Page 33 and 34: 35-2 Development of Iron-Based Pero
Page 35 and 36: features of the BGL 1000 technology
Page 37 and 38: Heat-exchangers, particle filters,
Page 39 and 40: 41-4 Using Fly Ash-Based Foundry Co
Page 41 and 42: ocks using elemental ratios. Data f
Page 43 and 44: 600-900°C. Changes in the amount o
Page 45 and 46: ATL process has three stages, namel
Page 47 and 48: commercial-scale gasifier was shutd
Page 49 and 50: 52-5 Pilot-Scale Demonstration of U
Page 51 and 52: POSTER SESSION 1 COMBUSTION TECHNOL
Page 53 and 54: experimental data available in lite
Page 55 and 56: activation. It was concluded that C

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