WorldWideScience

Sample records for technology coal combustion

  1. Coal slurry combustion and technology. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

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

  2. Clean coal technologies handbook: fluidized bed combustion

    Energy Technology Data Exchange (ETDEWEB)

    1999-01-01

    The term fluidisation is used to describe a type or mode of contact between fluids and granular solids, in such a way that solid particles appear as suspended in the moving fluid. The fluid moves vertically upwards through the bed formed by the particles. The reason to use the word fluidisation is that, when a solid particles bed is treated in the above mentioned way, it acquires an aspect very similar to that of a boiling liquid, and it has properties similar to those of a liquid. Thus, a bed in such conditions is called fluidised bed; the name fluidisation is reserved to the operation required to reach such state. This contacting method shows a number of fetaures which make it very useful to carry on many important processes in the fields of Chemical Engineering and Extractive Metallurgy; for that reason it has been studied very deeply in the last year, on the theoretical aspect and on its practical applications as well. Going back in time to the origin of the fluidisation, as it is known at present, we find that is started to develop at the beginning of the 1940's. The first application of fluidisation is described by Agricola in his famous book De re metallica, which must have been written in XVI the century. In this book there is the mention of the concentration of metallic ores by means of an expansion of the bed produced by a vertical upwards water flow which passes through the layer of rough mineral. From the beginning of its development, fluidisation has had many applications, such as water clarification, pulverised coal gasification, catalytic cracking chemical processes, drying of pulverulent materials and incineration of solid residues, among others. Until the end of 1950 the application was not used to coal combustion; it has strongly development after the energy crisis. Starting in the 1970's a great effort at world level is being made to develop the technology of Fluidised Bed Combustion (FBC), pushed on by two main reasons.: 1) Reduction

  3. SELECTION OF SUSTAINABLE TECHNOLOGIES FOR COMBUSTION OF BOSNIAN COALS

    Directory of Open Access Journals (Sweden)

    Anes Kazagić

    2010-01-01

    Full Text Available This paper deals with optimization of coal combustion conditions to support selection a sustainable combustion technology and an optimal furnace and boiler design. A methodology for optimization of coal combustion conditions is proposed and demonstrated on the example of Bosnian coals. The properties of Bosnian coals vary widely from one coal basin to the next, even between coal mines within the same basin. Very high percentage of ash (particularly in Bosnian brown coal makes clear certain differences between Bosnian coal types and other world coal types, providing a strong argument for investigating specific problems related to the combustion of Bosnian coals, as well as ways to improve their combustion behaviour. In this work, options of the referent energy system (boiler with different process temperatures, corresponding to the different combustion technologies; pulverised fuel combustion (slag tap or dry bottom furnace and fluidized bed combustion, are under consideration for the coals tested. Sustainability assessment, based on calculation economic and environment indicators, in combination with common low cost planning method, is used for the optimization. The total costs in the lifetime are presented by General index of total costs, calculated on the base of agglomeration of basic economic indicators and the economic indicators derived from environmental indicators. So, proposed methodology is based on identification of those combustion technologies and combustion conditions for coals tested for which the total costs in lifetime of the system under consideration are lowest, provided that all environmental issues of the energy system is fulfilled during the lifetime. Inputs for calculation of the sustainability indicators are provided by the measurements on an experimental furnace with possibility of infinite variation of process temperature, supported by good praxis from the power plants which use the fuels tested and by thermal

  4. Enhancement of pulverized coal combustion by plasma technology

    Energy Technology Data Exchange (ETDEWEB)

    Gorokhovski, M.A.; Jankoski, Z.; Lockwood, F.C.; Karpenko, E.I.; Messerle, V.E.; Ustimenko, A.B. [University of Rouen, Rouen (France)

    2007-07-01

    Plasma-assisted pulverized coal combustion is a promising technology for thermal power plants (TPP). This article reports one- and three- dimensional numerical simulations, as well as laboratory and industrial measurements of coal combustion using a plasma-fuel system (PFS). The chemical kinetic and fluid mechanics involved in this technology are analysed. The results show that a PFS, can be used to promote early ignition and enhanced stabilization of a pulverized coal flame. It is shown that this technology, in addition to enhancing the combustion efficiency of the flame, reduces harmful emissions from power coals of all ranks (brown, bituminous, anthracite and their mixtures). Data summarising the experience of 27 pulverized coal boilers in 16 thermal power plants in several countries (Russia, Kazakhstan, Korea, Ukraine, Slovakia, Mongolia and China), embracing steam productivities from 75 to 670 tons per hour (TPH), are presented. Finally, the practical computation of the characteristics of the PFS, as function of coal properties, is discussed.

  5. Commercial Demonstration of Oxy-Coal Combustion Clean Power Technology

    Energy Technology Data Exchange (ETDEWEB)

    K.J. McCauley; K.C. Alexander; D.K. McDonald; N. Perrin; J.-P. Tranier [Babcock & Wilcox Power Generation Group (United Kingdom)

    2009-07-01

    Oxy-Coal Combustion is an advanced clean coal-based power generation technology with carbon capture and storage that will be Near Zero Emissions (NZEP), will capture and safely store CO{sub 2} in a geologic formation, and generate clean power for sale. This sustainable technology will utilize natural resources and support energy security goals. The unique benefits of oxy-coal combustion allow for near zero emissions of coal combustion products. The emissions of particulate matter, sulfur dioxide, nitrogen oxides and mercury will not only be below regulated levels, but all will be within the uncertainty of current industry measurement methods, essentially zero. This advanced technology will demonstrate all these reduced levels and will lead to commercially available NZEP plants for power generation. Since 1991, with the support of the US-DOE, Babcock & Wilcox Power Generation Group, Inc. (B&W PGG) and Air Liquide (AL) have worked to bring an advanced technology to the market for Carbon Capture and Storage (CCS) for coal-fired electric power generation plants. Oxy-coal combustion is now ready for at-scale demonstration leading directly to full scale commercialization and availability in the power generation marketplace. This paper will discuss the follow up of the results of the 30 MWth large pilot test program completed in December, 2008. This oxy-coal combustion technology has been through small lab pilot testing, large pilot testing, and a rigorous bottom-up integration and optimization analysis. Our paper will describe incorporating the best technological thinking for the integration of a modern PC-fired boiler, environmental control equipment, air separation unit (ASU) and compression purification unit (CPU). 5 refs., 3 figs.

  6. Joule II - Programme. Clean coal technology R & D. 2nd phase. Volume III. Atmospheric combustion of pulverized coal and coal based blends for power generation

    Energy Technology Data Exchange (ETDEWEB)

    Hein, K.R.G.; Minchener, A.J.; Pruschek, R.; Roberts, P.A. [eds.

    1998-12-31

    Topics covered in this Joule II clean coal technology publication include: coal preparation and blending; cocombustion of coal with biomass and wastes; flame modelling; NO{sub x} abatement by combustion control and staging; coal quality and NO{sub x} emissions; coal combustion properties; and fluidized bed combustion of coal. All papers have been abstracted separately.

  7. Coal Combustion Science

    Energy Technology Data Exchange (ETDEWEB)

    Hardesty, D.R. (ed.); Fletcher, T.H.; Hurt, R.H.; Baxter, L.L. (Sandia National Labs., Livermore, CA (United States))

    1991-08-01

    The objective of this activity is to support the Office of Fossil Energy in executing research on coal combustion science. This activity consists of basic research on coal combustion that supports both the Pittsburgh Energy Technology Center Direct Utilization Advanced Research and Technology Development Program, and the International Energy Agency Coal Combustion Science Project. Specific tasks for this activity include: (1) coal devolatilization - the objective of this risk is to characterize the physical and chemical processes that constitute the early devolatilization phase of coal combustion as a function of coal type, heating rate, particle size and temperature, and gas phase temperature and oxidizer concentration; (2) coal char combustion -the objective of this task is to characterize the physical and chemical processes involved during coal char combustion as a function of coal type, particle size and temperature, and gas phase temperature and oxygen concentration; (3) fate of mineral matter during coal combustion - the objective of this task is to establish a quantitative understanding of the mechanisms and rates of transformation, fragmentation, and deposition of mineral matter in coal combustion environments as a function of coal type, particle size and temperature, the initial forms and distribution of mineral species in the unreacted coal, and the local gas temperature and composition.

  8. The development of pollution control technology in coal combustion in China

    Institute of Scientific and Technical Information of China (English)

    XU Xuchang; ZHANG Hu; ZHUO Yuqun; TONG Huiling; WANG Shujuan; LI Yan

    2007-01-01

    The recent development of coal combustion pollution control technologies in China,including desulphurization,denitrification,particulate matters and heavy metals emission control technologies,have been reviewed.The development histories and the advantages of China's self-developed technologies have been introduced in detail.The key points of future research and development in coal combustion pollution control,e.g.,combined emission control and CO2 emission control technologies,have also been discussed.

  9. Clean coal combustion: development of clean combustion technologies for residual fuels

    Energy Technology Data Exchange (ETDEWEB)

    Montiel, M.F. [Electric Research Institute, Cuernavaca (Mexico)

    2003-07-01

    Most of the large quantities of heavy fuel oil (about 4% sulphur-content) produced in Mexican refineries are burned in power plants. More natural gas is being used, and it is estimated that by 2010, about one-third of Mexico's electricity will be produced from natural gas. As petroleum and gas reserves are depleted, power plants will consume more imported coal. To continue combustion of dirty fuels, advanced clean combustion technologies must be developed. Two feasibility projects were conducted over the period 1989-1995 on combustion of Mexican fuels in a bubbling fluidized combustor and in IGCC power plants. More recent feasibility studies for cogeneration plants in refineries are outlined. Solid fuels for IGCC and CFB are among the most important developments. Over the period 2004-2008, projects to study clean combustion of Mexican fuels will be conducted in the following areas: operational problems in IGCC plants, construction of an entrained flow gasifier for synthesis gas production and for feeding of heavy fuels and coal emulsions, and development of CFD (computational fluid dynamics) models.

  10. Coal combustion research

    Energy Technology Data Exchange (ETDEWEB)

    Daw, C.S.

    1996-06-01

    This section describes research and development related to coal combustion being performed for the Fossil Energy Program under the direction of the Morgantown Energy Technology Center. The key activity involves the application of chaos theory for the diagnosis and control of fossil energy processes.

  11. Coal combustion products

    Science.gov (United States)

    Kalyoncu, R.S.; Olson, D.W.

    2001-01-01

    Coal-burning powerplants, which supply more than half of U.S. electricity, also generate coal combustion products, which can be both a resource and a disposal problem. The U.S. Geological Survey collaborates with the American Coal Ash Association in preparing its annual report on coal combustion products. This Fact Sheet answers questions about present and potential uses of coal combustion products.

  12. Development and evaluation of coal/water mixture combustion technology. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Scheffee, R.S.; Rossmeissl, N.P.; Skolnik, E.G.; McHale, E.T.

    1981-08-01

    The objective was to advance the technology for the preparation, storage, handling and combustion of highly-loaded coal/water mixtures. A systematic program to prepare and experimentally evaluate coal/water mixtures was conducted to develop mixtures which (1) burn efficiently using combustion chambers and burners designed for oil, (2) can be provided at a cost less than that of No. 6 oil, and (3) can be easily transported and stored. The program consisted of three principal tasks. The first was a literature survey relevant to coal/water mixture technology. The second involved slurry preparation and evaluation of rheological and stability properties, and processing techniques. The third consisted of combustion tests to characterize equipment and slurry parameters. The first task comprised a complete search of the literature, results of which are tabulated in Appendix A. Task 2 was involved with the evaluation of composition and process variables on slurry rheology and stability. Three bituminous coals, representing a range of values of volatile content, ash content, and hardness were used in the slurries. Task 3 was concerned with the combustion behavior of coal/water slurry. The studies involved first upgrading of an experimental furnace facility, which was used to burn slurry fuels, with emphasis on studying the effect on combustion of slurry properties such as viscosity and particle size, and the effect of equipment parameters such as secondary air preheat and atomization.

  13. Oxy Coal Combustion at the US EPA

    Science.gov (United States)

    Oxygen enriched coal (oxy-coal) combustion is a developing, and potentially a strategically key technology intended to accommodate direct CO2 recovery and sequestration. Oxy-coal combustion is also intended for retrofit application to existing power plants. During oxy-coal comb...

  14. Fluidized coal combustion

    Science.gov (United States)

    Moynihan, P. I.; Young, D. L.

    1979-01-01

    Fluidized-bed coal combustion process, in which pulverized coal and limestone are burned in presence of forced air, may lead to efficient, reliable boilers with low sulfur dioxide and nitrogen dioxide emissions.

  15. TENORM: Coal Combustion Residuals

    Science.gov (United States)

    Burning coal in boilers to create steam for power generation and industrial applications produces a number of combustion residuals. Naturally radioactive materials that were in the coal mostly end up in fly ash, bottom ash and boiler slag.

  16. Reducing the cost of post combustion capture technology for pulverized coal power plants by flexible operation

    NARCIS (Netherlands)

    Kler, R.C.F. de; Verbaan, M.; Goetheer, E.L.V.

    2013-01-01

    Currently the low carbon prices, low Spreads and regulatory uncertainties hampers the business cases for coal-fired power plants with post-combustion capture (PCC) in Europe. Improvement of the business case of coal-fired power plants with post combustion capture requires a different approach in

  17. Reducing the cost of Post Combustion Capture technology for Pulverized Coal Power Plants by flexible operation

    NARCIS (Netherlands)

    De Kler, R.C.F.; Verbaan, M.; Goetheer, E.L.V.

    2013-01-01

    Currently the low carbon prices, low Spreads and regulatory uncertainties hampers the business cases for coal-fired power plants with post-combustion capture (PCC) in Europe. Improvement of the business case of coal-fired power plants with post combustion capture requires a different approach in

  18. Reducing the cost of Post Combustion Capture technology for Pulverized Coal Power Plants by flexible operation

    NARCIS (Netherlands)

    De Kler, R.C.F.; Verbaan, M.; Goetheer, E.L.V.

    2013-01-01

    Currently the low carbon prices, low Spreads and regulatory uncertainties hampers the business cases for coal-fired power plants with post-combustion capture (PCC) in Europe. Improvement of the business case of coal-fired power plants with post combustion capture requires a different approach in ter

  19. Joule II - Programme. Clean coal technology R & D. 2nd phase. Volume III. Novel approaches in advanced combustion (pressurized systems)

    Energy Technology Data Exchange (ETDEWEB)

    Hein, K.R.G.; Minchener, A.J.; Pruschek, R.; Roberts, P.A. [eds.

    1998-12-31

    A total of 22 papers are presented in this report on topics including advanced reburning; pulverized coal combustion systems; fluidized bed combustion; pressurizing combustion; fuel particle characterisation; coal and biomass cocombustion; gasification of coal and biomass; and particle pyrolysis. All papers have been abstracted separately for the IEA Coal Research CD-ROM and website.

  20. Mineral processing technologies used to obtain valuable components of the solid wastes from coal combustion in power plants

    Directory of Open Access Journals (Sweden)

    Martin Sisol

    2005-11-01

    Full Text Available This paper presents mineral processing technologies used to achieve components from solid wastes of coal combusted in power plants. By combusting bituminous coal in smelting boilers, mineral novelties are formed which are separable by suitable mineral processing technologies. The separation of unburned coal residues is realized by flotation, using nonionic flotation agents such as Flotalex MR, Flotalex bio, Flotakol NX and others. The Fe component created by the mineral novelty of magnetite is obtained by wet and dry low-intensity magnetic separation. Optimal results were accomplished by the flotation process in which we obtained residues of unburned coal. The waste from the flotation was consequently separated by the wet low-intensity separation. The waste from the flotation and magnetic separation - subtilized fly ash, contained 0 – 2,5% LOI which can be used in architecture.

  1. Pressurised fluidised bed combustion: an alternative clean coal technology. La combustion en lecho fluido a presion, una alternativa de uso limpio del carbon en desarollo

    Energy Technology Data Exchange (ETDEWEB)

    Bencomo Perez-Zamora, V.; Menendez Perez, J.A.E. (ENDESA, Madrid (Spain))

    1988-11-01

    The primary aim of thistechnology is to reduce emissions of sulphur and nitrous oxides. Pilot plant tests have achieved a sulphur fixing rate of over 95%. Pressurised fluidised bed combustion also has advantages with regard to the emission of contaminants. Halogens, fluorine and chlorine, which in conventional combustion methods are released in the gases, to a large degree remain in the ash as do trace elements, such as arsenic, which usually vapourise at high temperatures in pulverised coal combustors. This technology also has a high output of between 38 and 40% net according to the type of coal used. 10 figs., 10 tabs.

  2. Comparisons between oxy-fuel combustion and IGCC technologies in China coal- energy industry

    OpenAIRE

    Zhao, Xue; Clemente Jul, María del Carmen

    2010-01-01

    A comparison between oxy-fuel combustion plants and IGCC plants has been carried out. Oxy-fuel combustion performs better for the retrofit of exist pulverized coal plants after the evaluation of efficiency, retrofit cost and O&M cost. China is currently and will depending on coal for its energy for a long time. Plenty of PC plants are used in existing power plants due to its lower coal consumption. One way to reduce CO2 emission with CCS is to equip existing power plants with appliance...

  3. TOXIC SUBSTANCES FROM COAL COMBUSTION

    Energy Technology Data Exchange (ETDEWEB)

    A KOLKER; AF SAROFIM; CL SENIOR; FE HUGGINS; GP HUFFMAN; I OLMEZ; J LIGHTY; JOL WENDT; JOSEPH J HELBLE; MR AMES; N YAP; R FINKELMAN; T PANAGIOTOU; W SEAMES

    1998-12-08

    The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPs) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the Federal Energy Technology Center (FETC), the Electric Power Research Institute, the Lignite Research Council, and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (UU) and the University of North Dakota Energy and Environmental Research Center (EERC) to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NO combustion systems, and new power generation x plants. Development of ToPEM will be based on PSI's existing Engineering Model for Ash Formation (EMAF). This report covers the reporting period from 1 July 1998 through 30 September 1998. During this period distribution of all three Phase II coals was completed. Standard analyses for the whole coal samples were also completed. Mössbauer analysis of all project coals and fractions received to date has been completed in order to obtain details of the iron mineralogy. The analyses of arsenic XAFS data for two of the project coals and for some high arsenic coals have been completed. Duplicate splits of the Ohio 5,6,7 and North Dakota lignite samples were taken through all four steps of the selective leaching procedure. Leaching analysis of the Wyodak coal has recently commenced. Preparation of polished coal/epoxy pellets for probe/SEM studies is underway. Some exploratory mercury LIII XAFS work was

  4. A Pulverized Coal-Fired Boiler Optimized for Oxyfuel Combustion Technology

    Directory of Open Access Journals (Sweden)

    Tomáš Dlouhý

    2012-01-01

    Full Text Available This paper presents the results of a study on modifying a pulverized coal-fired steam boiler in a 250 MWe power plant for oxygen combustion conditions. The entry point of the study is a boiler that was designed for standard air combustion. It has been proven that simply substituting air by oxygen as an oxidizer is not sufficient for maintaining a satisfactory operating mode, not even with flue gas recycling. Boiler design optimization aggregating modifications to the boiler’s dimensions, heating surfaces and recycled flue gas flow rate, and specification of a flue gas recycling extraction point is therefore necessary in order to achieve suitable conditions for oxygen combustion. Attention is given to reducing boiler leakage, to which external pre-combustion coal drying makes a major contribution. The optimization is carried out with regard to an overall power plant conception for which a decrease in efficiency due to CO2 separation is formulated.

  5. Pilot Testing of WRI'S Novel Mercury Control Technology by Pre-Combustion Thermal Treatment of Coal

    Energy Technology Data Exchange (ETDEWEB)

    Alan Bland; Jesse Newcomer; Kumar Sellakumar

    2008-08-17

    The challenges to the coal-fired power industry continue to focus on the emission control technologies, such as mercury, and plant efficiency improvements. An alternate approach to post-combustion control of mercury, while improving plant efficiency deals with Western Research Institute's (WRI)'s patented pre-combustion mercury removal and coal upgrading technology. WRI was awarded under the DOE's Phase III Mercury program, to evaluate the effectiveness of WRI's novel thermal pretreatment process to achieve >50% mercury removal, and at costs of <$30,000/lb of Hg removed. WRI has teamed with Etaa Energy, Energy and Environmental Research Center (EERC), Foster Wheeler North America Corp. (FWNA), and Washington Division of URS (WD-URS), and with project co-sponsors including Electric Power Research Institute (EPRI), Southern Company, Basin Electric Power Cooperative (BEPC), Montana-Dakota Utilities (MDU), North Dakota Industrial Commission (NDIC), Detroit Edison (DTE), and SaskPower to undertake this evaluation. The technical objectives of the project were structured in two phases: Phase I--coal selection and characterization, and bench-and PDU-scale WRI process testing and; and Phase II--pilot-scale pc combustion testing, design of an integrated boiler commercial configuration, its impacts on the boiler performance and the economics of the technology related to market applications. This report covers the results of the Phase I testing. The conclusion of the Phase I testing was that the WRI process is a technically viable technology for (1) removing essentially all of the moisture from low rank coals, thereby raising the heating value of the coal by about 30% for subbituminous coals and up to 40% for lignite coals, and (2) for removing volatile trace mercury species (up to 89%) from the coal prior to combustion. The results established that the process meets the goals of DOE of removing <50% of the mercury from the coals by pre-combustion methods

  6. Clean coal technologies market potential

    Energy Technology Data Exchange (ETDEWEB)

    Drazga, B. (ed.)

    2007-01-30

    Looking at the growing popularity of these technologies and of this industry, the report presents an in-depth analysis of all the various technologies involved in cleaning coal and protecting the environment. It analyzes upcoming and present day technologies such as gasification, combustion, and others. It looks at the various technological aspects, economic aspects, and the various programs involved in promoting these emerging green technologies. Contents: Industry background; What is coal?; Historical background of coal; Composition of coal; Types of coal; Environmental effects of coal; Managing wastes from coal; Introduction to clean coal; What is clean coal?; Byproducts of clean coal; Uses of clean coal; Support and opposition; Price of clean coal; Examining clean coal technologies; Coal washing; Advanced pollution control systems; Advanced power generating systems; Pulverized coal combustion (PCC); Carbon capture and storage; Capture and separation of carbon dioxide; Storage and sequestration of carbon dioxide; Economics and research and development; Industry initiatives; Clean Coal Power Initiative; Clean Coal Technology Program; Coal21; Outlook; Case Studies.

  7. Coal combustion science. Quarterly progress report, July--September 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hardesty, D.R. [ed.; Baxter, L.L.; Davis, K.A.; Hurt, R.H.; Yang, N.Y.C.

    1995-09-01

    This document is a quarterly status report of the Coal Combustion Science Project that is being conducted at the Combustion Research Facility, Sandia National Laboratories, Livermore, California. The information reported is for the period July-September 1994. The objective of this work is to support the Office of Fossil Energy in executing research on coal combustion science. This project consists of basic research on coal combustion that supports both the Pittsburgh Energy Technology Center (PETC) Direct Utilization Advanced Research and Technology Development Program, and the International Energy Agency (IEA) Coal Combustion Science Project.

  8. Coal char fragmentation during pulverized coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, L.L.

    1995-07-01

    A series of investigations of coal and char fragmentation during pulverized coal combustion is reported for a suite of coals ranging in rank from lignite to low-volatile (lv) bituminous coal under combustion conditions similar to those found in commercial-scale boilers. Experimental measurements are described that utilize identical particle sizing characteristics to determine initial and final size distributions. Mechanistic interpretation of the data suggest that coal fragmentation is an insignificant event and that char fragmentation is controlled by char structure. Chars forming cenospheres fragment more extensively than solid chars. Among the chars that fragment, large particles produce more fine material than small particles. In all cases, coal and char fragmentation are seen to be sufficiently minor as to be relatively insignificant factors influencing fly ash size distribution, particle loading, and char burnout.

  9. Coal combustion science. Quarterly progress report, April 1993--June 1993

    Energy Technology Data Exchange (ETDEWEB)

    Hardesty, D.R. [ed.

    1994-05-01

    This document is a quarterly status report of the Coal Combustion Science Project that is being conducted at the Combustion Research Facility, Sandia National Laboratories. The information reported is for Apr-Jun 1993. The objective of this work is to support the Office of Fossil Energy in executing research on coal combustion science. This project consists of basic research on coal combustion that supports both the PETC Direct Utilization Advanced Research and Technology Development Program, and the International Energy Agency Coal Combustion Science Project. The objective of the kinetics and mechanisms of pulverized coal char combustion task is to characterize the combustion behavior of selected US coals under conditions relevant to industrial pulverized coal-fired furnaces. Work is being done in four areas: kinetics of heterogeneous fuel particle populations; char combustion kinetics at high carbon conversion; the role of particle structure and the char formation process in combustion and; unification of the Sandia char combustion data base. This data base on the high temperature reactivities of chars from strategic US coals will permit identification of important fuel-specific trends and development of predictive capabilities for advanced coal combustion systems. The objective of the fate of inorganic material during coal combustion task is the establish a quantitative understanding of the mechanisms and rates of transformation, fragmentation, and deposition of inorganic material during coal combustion as a function of coal type, particle size and temperature, the initial forms and distribution of inorganic species in the unreacted coal, and the local gas temperature and composition. In addition, optical diagnostic capabilities are being developed for in situ, real-time detection of inorganic vapor species and surface species during ash deposition. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  10. FUNDAMENTAL INVESTIGATION OF FUEL TRANSFORMATIONS IN PULVERIZED COAL COMBUSTION AND GASIFICATION TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Robert Hurt; Joseph Calo; Thomas H. Fletcher; Alan Sayre

    2005-04-29

    The goal of this project was to carry out the necessary experiments and analyses to extend current capabilities for modeling fuel transformations to the new conditions anticipated in next-generation coal-based, fuel-flexible combustion and gasification processes. This multi-organization, multi-investigator project has produced data, correlations, and submodels that extend present capabilities in pressure, temperature, and fuel type. The combined experimental and theoretical/computational results are documented in detail in Chapters 1-8 of this report, with Chapter 9 serving as a brief summary of the main conclusions. Chapters 1-3 deal with the effect of elevated pressure on devolatilization, char formation, and char properties. Chapters 4 and 5 deal with advanced combustion kinetic models needed to cover the extended ranges of pressure and temperature expected in next-generation furnaces. Chapter 6 deals with the extension of kinetic data to a variety of alternative solid fuels. Chapter 7 focuses on the kinetics of gasification (rather than combustion) at elevated pressure. Finally, Chapter 8 describes the integration, testing, and use of new fuel transformation submodels into a comprehensive CFD framework. Overall, the effects of elevated pressure, temperature, heating rate, and alternative fuel use are all complex and much more work could be further undertaken in this area. Nevertheless, the current project with its new data, correlations, and computer models provides a much improved basis for model-based design of next generation systems operating under these new conditions.

  11. Oxy-coal Combustion Studies

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, J. [Univ. of Utah, Salt Lake City, UT (United States); Eddings, E. [Univ. of Utah, Salt Lake City, UT (United States); Lighty, J. [Univ. of Utah, Salt Lake City, UT (United States); Ring, T. [Univ. of Utah, Salt Lake City, UT (United States); Smith, P. [Univ. of Utah, Salt Lake City, UT (United States); Thornock, J. [Univ. of Utah, Salt Lake City, UT (United States); Y Jia, W. Morris [Univ. of Utah, Salt Lake City, UT (United States); Pedel, J. [Univ. of Utah, Salt Lake City, UT (United States); Rezeai, D. [Univ. of Utah, Salt Lake City, UT (United States); Wang, L. [Univ. of Utah, Salt Lake City, UT (United States); Zhang, J. [Univ. of Utah, Salt Lake City, UT (United States); Kelly, K. [Univ. of Utah, Salt Lake City, UT (United States)

    2012-01-06

    The objective of this project is to move toward the development of a predictive capability with quantified uncertainty bounds for pilot-scale, single-burner, oxy-coal operation. This validation research brings together multi-scale experimental measurements and computer simulations. The combination of simulation development and validation experiments is designed to lead to predictive tools for the performance of existing air fired pulverized coal boilers that have been retrofitted to various oxy-firing configurations. In addition, this report also describes novel research results related to oxy-combustion in circulating fluidized beds. For pulverized coal combustion configurations, particular attention is focused on the effect of oxy-firing on ignition and coal-flame stability, and on the subsequent partitioning mechanisms of the ash aerosol.

  12. FUNDAMENTAL INVESTIGATION OF FUEL TRANSFORMATIONS IN PULVERIZED COAL COMBUSTION AND GASIFICATION TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Robert Hurt; Joseph Calo; Thomas Fletcher; Alan Sayre

    2004-01-01

    The goal of this project is to carry out the necessary experiments and analyses to extend leading submodels of coal transformations to the new conditions anticipated in next-generation energy technologies. During the first two projects years, significant progress was made on most of the tasks, as described in detail in the two previous annual reports. In the current third annual report, we report in detail on the BYU task on the properties and intrinsic reactivities of chars prepared at high-pressure. A flat-flame burner was used in a high pressure laminar flow facility to conduct high temperature, high heating rate coal pyrolysis experiments. Heating rates were approximately 10{sup 5} K/s, which is higher than in conventional drop tube experiments. Char samples from a Pitt No.8 coal and lignite were collected at 1300 C at 1, 6, 10, and 15 atm. Swelling ratios of the lignite were less than 1.0, and only about 1.3 for the Pitt No.8 coal. All coals showed slight increases in swelling behavior as pressure increased. The swelling behavior observed for the Pitt No.8 coal at each pressure was lower than reported in high pressure drop tube experiments, indicating the effect of heating rate on particle swelling. This heating rate effect was similar to that observed previously at atmospheric pressure. SEM photos revealed that bituminous coal has large physical structure transformations, with popped bubbles due to the high heating rate. TGA char oxidation reactivities were measured at the same total pressure as the char preparation pressure. The general trend was that the TGA reactivity on a gram per gram available basis decreased for both Pitt No.8 and Knife River lignite coal chars with increasing char formation pressure. The Pitt No.8 char intrinsic activation energy and oxygen reaction order remained relatively constant with increasing pressure. This new data provides some of the only information available on the morphology, structure, and reactivity of chars prepared in

  13. Basic theory research of coal spontaneous combustion

    Institute of Scientific and Technical Information of China (English)

    WANG Ji-ren; SUN Yan-qiu; ZHAO Qing-fu; DENG Cun-bao; DENG Han-zhong

    2008-01-01

    Discussed latest research results of basic theory research of coal spontaneous combustion in detail, with quantum chemical theory and method and experiment systematically studied chemical structure of coal molecule, adsorption mechanism of coal surface to oxygen molecule and chemical reaction mechanism and process of spontaneous combustion of organic macromolecule and low molecular weight compound in coal from microcosmic view, and established complete theoretical system of the mechanism of coal spontaneous combustion.

  14. Fluidized bed combustion of high ash Singareni coal

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, M.K.; Biswas, R.R.; Mukherjee, S.K.; Talapatra, P.C.; Roy, R.U.; Rao, S.K.; Sen, M.M.

    1986-04-01

    Fluid bed combustion is comparatively a new technology for efficient combustion of high ash coals, which constitute the bulk of Indian coal resources. A 2-tonne equivalent steam per hour fluid bed combustion boiler was installed at the CPRI for experimentation with Indian coals and this paper discusses the salient features of tests conducted in the unit with minus 6 mm high ash Singareni coal of Andhra Pradesh. Data on combustion, heat transfer and heat utilization characteristics of the boiler under varying operating conditions show that high ash Singareni coal slacks can be burnt efficiently with high thermal efficiency, combustion efficiency and heat transfer rates from bed to surface in direct contact in a fluid bed combustion boiler. 3 refs., 5 figs., 4 tabs.

  15. Sulphur impacts during pulverised coal combustion in oxy-fuel technology for carbon capture and storage

    Energy Technology Data Exchange (ETDEWEB)

    Stanger, Rohan; Wall, Terry [Chemical Engineering, University of Newcastle, Callaghan, NSW (Australia)

    2011-02-15

    The oxy-fuel process is one of three carbon capture technologies which supply CO{sub 2} ready for sequestration - the others being post-combustion capture and IGCC with carbon capture. As yet no technology has emerged as a clear winner in the race to commercial deployment. The oxy-fuel process relies on recycled flue gas as the main heat carrier through the boiler and results in significantly different flue gas compositions. Sulphur has been shown in the study to have impacts in the furnace, during ash collection, CO{sub 2} compression and transport as well as storage, with many options for its removal or impact control. In particular, the effect of sulphur containing species can pose a risk for corrosion throughout the plant and transport pipelines. This paper presents a technical review of all laboratory and pilot work to identify impacts of sulphur impurities from throughout the oxy-fuel process, from combustion, gas cleaning, compression to sequestration with removal and remedial options. An economic assessment of the optimum removal is not considered. Recent oxy-fuel pilot trials performed in support of the Callide Oxy-fuel Project and other pilot scale data are interpreted and combined with thermodynamic simulations to develop a greater fundamental understanding of the changes incurred by recycling the flue gas. The simulations include a sensitivity analysis of process variables and comparisons between air fired and oxy-fuel fired conditions - such as combustion products, SO{sub 3} conversion and limestone addition. (author)

  16. FUNDAMENTAL INVESTIGATION OF FUEL TRANSFORMATIONS IN PULVERIZED COAL COMBUSTION AND GASIFICATION TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Robert Hurt; Joseph Calo; Thomas Fletcher; Alan Sayre

    2003-01-01

    The goal of this project is to carry out the necessary experiments and analyses to extend leading submodels of coal transformations to the new conditions anticipated in next-generation energy technologies. During the first project quarter, a technical kick-off meeting was held on the Brown campus involving PIs from Brown (Hurt, Calo), BYU (Fletcher), and B&W (Sayre, Burge). Following this first meeting the current version of CBK (Version 8) was transferred to B&W McDermott and the HP-CBK code developed by BYU was transferred to Brown to help guide the code development in this project. Also during the first project year, progress was reviewed at an all-hands meeting was held at Brigham Young University in August, 2001. The meeting was attended by PIs Fletcher, Hurt, Calo, and Sayre, and also by affiliated investigators Steven Burge from McDermott and Prof. William Hecker from BYU. During the first project year, significant progress was made on several fronts, as described in detail in the previous annual report. In the current second annual report, we report on progress made on two important project tasks. At Brown University: (1) Char combustion reactivities at 500 C in air were determined for a diverse set of solid fuels and organic model compound chars. These varied over 4 orders of magnitude for the chars prepared at 700 C, and over 3 orders of magnitude for the chars prepared at 1000 C. The resultant reactivities correlate poorly with organic elemental composition and with char surface area. (2) Specially-acquired model materials with minute amounts of inorganic matter exhibit low reactivities that fall in a narrow band as a function of wt-% carbon. Reactivities in this sample subset correlate reasonably well with total char surface area. (3) A hybrid chemical/statistical model was developed which explains most of the observed reactivity variation based on four variables: the amounts of nano-dispersed K, nanodispersed (Ca+Mg), elemental carbon (wt-% daf), and

  17. Nitrogen release during coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, L.L.; Mitchell, R.E.; Fletcher, T.H.; Hurt, R.H.

    1995-02-01

    Experiments in entrained flow reactors at combustion temperatures are performed to resolve the rank dependence of nitrogen release on an elemental basis for a suite of 15 U.S. coals ranging from lignite to low-volatile bituminous. Data were obtained as a function of particle conversion, with overall mass loss up to 99% on a dry, ash-free basis. Nitrogen release rates are presented relative to both carbon loss and overall mass loss. During devolatilization, fractional nitrogen release from low-rank coals is much slower than fractional mass release and noticeably slower than fractional carbon release. As coal rank increases, fractional nitrogen release rate relative to that of carbon and mass increases, with fractional nitrogen release rates exceeding fractional mass and fractional carbon release rates during devolatilization for high-rank (low-volatile bituminous) coals. At the onset of combustion, nitrogen release rates increase significantly. For all coals investigated, cumulative fractional nitrogen loss rates relative to those of mass and carbon passes through a maximum during the earliest stages of oxidation. The mechanism for generating this maximum is postulated to involve nascent thermal rupture of nitrogen-containing compounds and possible preferential oxidation of nitrogen sites. During later stages of oxidation, the cumulative fractional loss of nitrogen approaches that of carbon for all coals. Changes in the relative release rates of nitrogen compared to those of both overall mass and carbon during all stages of combustion are attributed to a combination of the chemical structure of coals, temperature histories during combustion, and char chemistry.

  18. Experimental research on combustion fluorine retention using calcium-based sorbets during coal combustion (Ⅰ)

    Institute of Scientific and Technical Information of China (English)

    QI Qing-jie; LIN Zhi-yan; LIU Jian-zhong; WU Xian; ZHOU Jun-hu; CEN Ke-fa

    2008-01-01

    In order to provide experimental guide to commercial use of fluorine pollution control during coal combustion, with fluorine pollution control during coal combustion in mind, this paper proposed the theory of combustion fluorine retention technology. Feasibility of fluorine retention reaction with calcium-based fluorine retention agent was analyzed through thermo-dynamic calculation during coal combustion. By simulating the restraining and retention effects and influential factors of calcium-based sorbets on vaporized fluoride during experimental combustion using fixed bed tube furnace, the paper systematically explored the influential law of such factors as combustion temperature, retention time, and added quantities of calcium-based sorbets on effects of fluorine retention. The research result shows that adding calcium-based fluorine retention agent in coal combustion has double effects of fluorine retention and sulfur retention, it lays an experimental foundation for commercial test of combustion fluorine retention.

  19. Coal Combustion Science. Quarterly progress report, October--December 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hardesty, D.R. [ed.; Baxter, L.L.; Davis, K.A.; Hurt, R.H.; Yang, N.Y.C.

    1996-02-01

    The objective of this work is to support the Office of Fossil Energy in executing research on coal combustion science. This project consists of basic research on coal combustion that supports both the Pittsburgh Energy Technology Center (PETC) Direct Utilization Advanced Research and Technology Development Program, and the International Energy Agency (IEA) Coal Combustion Science Project. Specific tasks include: Task 1--Kinetics and mechanisms of pulverized coal char combustion; and Task 2--deposit growth and property development in coal-fired furnaces. The objective of task 1 is to characterize the combustion behavior of selected US coals under conditions relevant to industrial pulverized coal-fired furnaces. Work is being done in four areas: (a) kinetics of heterogeneous fuel particle populations; (b) char combustion kinetics at high carbon conversion; (c) the role of particle structure and the char formation process in combustion and; (d) unification of the Sandia char combustion data base. The objectives of Task 2 are to provide a self-consistent database of simultaneously measured, time-resolved, ash deposit properties in well-controlled and well-defined environments and to provide analytical expressions that relate deposit composition and structure to deposit properties of immediate relevance to PETC`s Combustion 2000 program. The task include the development and use of diagnostics to monitor, in situ and in real time, deposit properties, including information on both the structure and composition of the deposits.

  20. Enhanced Combustion Low NOx Pulverized Coal Burner

    Energy Technology Data Exchange (ETDEWEB)

    David Towle; Richard Donais; Todd Hellewell; Robert Lewis; Robert Schrecengost

    2007-06-30

    For more than two decades, Alstom Power Inc. (Alstom) has developed a range of low cost, infurnace technologies for NOx emissions control for the domestic U.S. pulverized coal fired boiler market. This includes Alstom's internally developed TFS 2000{trademark} firing system, and various enhancements to it developed in concert with the U.S. Department of Energy. As of the date of this report, more than 270 units representing approximately 80,000 MWe of domestic coal fired capacity have been retrofit with Alstom low NOx technology. Best of class emissions range from 0.18 lb/MMBtu for bituminous coal to 0.10 lb/MMBtu for subbituminous coal, with typical levels at 0.24 lb/MMBtu and 0.13 lb/MMBtu, respectively. Despite these gains, NOx emissions limits in the U.S. continue to ratchet down for new and existing boiler equipment. On March 10, 2005, the Environmental Protection Agency (EPA) announced the Clean Air Interstate Rule (CAIR). CAIR requires 25 Eastern states to reduce NOx emissions from the power generation sector by 1.7 million tons in 2009 and 2.0 million tons by 2015. Low cost solutions to meet such regulations, and in particular those that can avoid the need for a costly selective catalytic reduction system (SCR), provide a strong incentive to continue to improve low NOx firing system technology to meet current and anticipated NOx control regulations. The overall objective of the work is to develop an enhanced combustion, low NOx pulverized coal burner, which, when integrated with Alstom's state-of-the-art, globally air staged low NOx firing systems will provide a means to achieve: Less than 0.15 lb/MMBtu NOx emissions when firing a high volatile Eastern or Western bituminous coal, Less than 0.10 lb/MMBtu NOx emissions when firing a subbituminous coal, NOx reduction costs at least 25% lower than the costs of an SCR, Validation of the NOx control technology developed through large (15 MWt) pilot scale demonstration, and Documentation required for

  1. Coal Combustion Products Extension Program

    Energy Technology Data Exchange (ETDEWEB)

    Tarunjit S. Butalia; William E. Wolfe

    2006-01-11

    This final project report presents the activities and accomplishments of the ''Coal Combustion Products Extension Program'' conducted at The Ohio State University from August 1, 2000 to June 30, 2005 to advance the beneficial uses of coal combustion products (CCPs) in highway and construction, mine reclamation, agricultural, and manufacturing sectors. The objective of this technology transfer/research program at The Ohio State University was to promote the increased use of Ohio CCPs (fly ash, FGD material, bottom ash, and boiler slag) in applications that are technically sound, environmentally benign, and commercially competitive. The project objective was accomplished by housing the CCP Extension Program within The Ohio State University College of Engineering with support from the university Extension Service and The Ohio State University Research Foundation. Dr. Tarunjit S. Butalia, an internationally reputed CCP expert and registered professional engineer, was the program coordinator. The program coordinator acted as liaison among CCP stakeholders in the state, produced information sheets, provided expertise in the field to those who desired it, sponsored and co-sponsored seminars, meetings, and speaking at these events, and generally worked to promote knowledge about the productive and proper application of CCPs as useful raw materials. The major accomplishments of the program were: (1) Increase in FGD material utilization rate from 8% in 1997 to more than 20% in 2005, and an increase in overall CCP utilization rate of 21% in 1997 to just under 30% in 2005 for the State of Ohio. (2) Recognition as a ''voice of trust'' among Ohio and national CCP stakeholders (particularly regulatory agencies). (3) Establishment of a national and international reputation, especially for the use of FGD materials and fly ash in construction applications. It is recommended that to increase Ohio's CCP utilization rate from 30% in 2005 to

  2. Relationship Between Coal Powder and Its Combustibility

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Coal's volatile component,ash and fixed carbon content have different functions in different stages of a combustion process, but the traditional coal classification can precisely show its combustion property.In this experiment coal's evaluation indexes (ignition index Di),(burn off index Df) were used to qualitatively show the ignition property and combustion ending property of coal samples.Meanwhile,considering actual heating circumstances in calciner (in cement plants),this thesis established the relationship among the ignition index,burn off index and coal's industrial analysis value, which makes it possible for the user to predict the quality of coal before using it and is very valuable in practice.

  3. Fluidized bed coal combustion reactor

    Science.gov (United States)

    Moynihan, P. I.; Young, D. L. (Inventor)

    1981-01-01

    A fluidized bed coal reactor includes a combination nozzle-injector ash-removal unit formed by a grid of closely spaced open channels, each containing a worm screw conveyor, which function as continuous ash removal troughs. A pressurized air-coal mixture is introduced below the unit and is injected through the elongated nozzles formed by the spaces between the channels. The ash build-up in the troughs protects the worm screw conveyors as does the cooling action of the injected mixture. The ash layer and the pressure from the injectors support a fluidized flame combustion zone above the grid which heats water in boiler tubes disposed within and/or above the combustion zone and/or within the walls of the reactor.

  4. Microwave plasma combustion of coal

    Energy Technology Data Exchange (ETDEWEB)

    P.M. Kanilo; V.I. Kazantsev; N.I. Rasyuk; K. Schuenemann; D.M. Vavriv [Institute of Machine Building Problems of the National Academy of Sciences of Ukraine, Kharkov (Ukraine)

    2003-01-01

    Microwave plasma is studied as an alternative to oil or gas fuel for ignition and stabilisation of burning of lean coal. The study is performed on an experimental set-up, which includes a burner with a microwave plasma generator, coal and air supply systems, and measurement equipment. Power and thermochemical characteristics of the coal-plasma interaction have been measured and analysed. The obtained results indicate an essential intensification of ignition and combustion processes in the microwave burner compared to those in conventional burners. In particular, it has been demonstrated that the microwave energy consumption is only about 10% of the required expenditure of oil or gas, measured in heat equivalent. A design of an industrial microwave-plasma burner is proposed. Prospects of such burner for applications at industrial boilers of power plants are discussed. 6 refs., 4 figs., 2 tabs.

  5. Oxy-Fuel Combustion of Coal

    DEFF Research Database (Denmark)

    Brix, Jacob

    This Ph.D. thesis describes an experimental and modeling investigation of the thermal conversion of coal and an experimental investigation of the emission of NO from char combustion in O2/N2 and O2/CO2 atmospheres. The motivation for the work has been the prospective use of the technology “Oxy...... the experiments. Devolatilization experiments showed that the volatile weight loss was not affected by the change from N2 to CO2. Analysis by Scanning Electron Microscopy (SEM) and Brunauer-Emmett-Teller (BET) surface area of sampled char did not reveal differences between the two atmospheres either. Char...... gasification though using only EFR-char devolatilized at 1273 K, 1473 K and 1573 K due to a lack of samples. Interestingly, it was found that devolatilization temperature did not affect the gasification rate constant. A detailed COal COmbustion MOdel (COCOMO) encompassing among others the three char...

  6. Study of mechanically activated coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Anatolij P. Burdukov; Vitalij A. Popov; Valentin A. Faleev [Institute of Thermophysics, Novosibirsk (Russian Federation)

    2009-07-01

    Combustion and air gasification of mechanically activated micro-ground coals in the flux have been studied. Influence of mechanically activated methods of coal grinding on their chemical activity at combustion and gasification has been determined. Intense mechanical activation of coals increases their chemical activity that enables development of new highly boosted processing methods for coals with various levels of metamorphism. 10 refs., 14 figs., 1 tab.

  7. Combustion characterization of beneficiated coal-based fuels

    Energy Technology Data Exchange (ETDEWEB)

    Chow, O.K.; Levasseur, A.A.

    1995-11-01

    The Pittsburgh Energy Technology Center (PETC) of the U.S. Department of Energy is sponsoring the development of advanced coal-cleaning technologies aimed at expanding the use of the nation`s vast coal reserves in an environmentally and economically acceptable manner. Because of the lack of practical experience with deeply beneficiated coal-based fuels, PETC has contracted Combustion Engineering, Inc. to perform a multi-year project on `Combustion Characterization of Beneficiated Coal-Based Fuels.` The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of Beneficiated Coal-Based Fuels (BCs) influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs.

  8. Reserch process geomigration during underground gasification and coal combustion

    Directory of Open Access Journals (Sweden)

    Zholudyev S.V.

    2014-12-01

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

  9. Plasma-supported coal combustion in boiler furnace

    Energy Technology Data Exchange (ETDEWEB)

    Askarova, A.S.; Karpenko, E.I.; Lavrishcheva, Y.I.; Messerle, V.E.; Ustimenko, A.B. [Kazakh National University, Alma Ata (Kazakhstan). Dept. of Physics

    2007-12-15

    Plasma activation promotes more effective and environmentally friendly low-rank coal combustion. This paper presents Plasma Fuel Systems that increase the burning efficiency of coal. The systems were tested for fuel oil-free start-up of coal-fired boilers and stabilization of a pulverized-coal flame in power-generating boilers equipped with different types of burners, and burning all types of power-generating coal. Also, numerical modeling results of a plasma thermochemical preparation of pulverized coal for ignition and combustion in the furnace of a utility boiler are discussed in this paper. Two kinetic mathematical models were used in the investigation of the processes of air/fuel mixture plasma activation: ignition and combustion. A I-D kinetic code PLASMA-COAL calculates the concentrations of species, temperatures, and velocities of the treated coal/air mixture in a burner incorporating a plasma source. The I-D simulation results are initial data for the 3-D-modeling of power boiler furnaces by the code FLOREAN. A comprehensive image of plasma-activated coal combustion processes in a furnace of a pulverized-coal-fired boiler was obtained. The advantages of the plasma technology are clearly demonstrated.

  10. Environmental control implications of generating electric power from coal. 1977 technology status report. Appendix D. Assessment of NO/sub x/ control technology for coal fired utility boilers. [Low-excess-air, staged combustion, flu gas recirculation and burner design

    Energy Technology Data Exchange (ETDEWEB)

    1977-12-01

    An NOx control technology assessment study was conducted to examine the effectiveness of low-excess-air firing, staged combustion, flue gas recirculation, and current burner/boiler designs as applied to coal-fired utility boilers. Significant variations in NOx emissions exist with boiler type, firing method, and coal type, but a relative comparison of emissions control performance, cost, and operational considerations is presented for each method. The study emphasized the numerous operational factors that are of major importance to the user in selecting and implementing a combustion modification technique. Staged combustion and low-excess-air operation were identified as the most cost-effective methods for existing units. Close control of local air/fuel ratios and rigorous combustion equipment maintenance are essential to the success of both methods. Flue gas recirculation is relatively ineffective and has the added concern of tube erosion. More research is needed to resolve potential corrosion concerns with low-NOx operating modes. Low-NOx burners in conjunction with a compartmentalized windbox are capable of meeting a 0.6-lb/million Btu emission level on new units. Advanced burner designs are being developed to meet research emission goals of approximately 0.25 lb/MBtu.

  11. Coal power and combustion. Quarterly report, January--March 1977

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-12-01

    ERDA's coal combustion and power program has focused on two major areas: Direct combustion of coal and advanced power systems. Efforts in the area of direct combustion are concentrated on: Development of atmospheric and pressurized systems capable of burning high-sulfur coal of all rank and quality in fluidized-bed combustors; development of advanced technology power systems to generate power more economically than present technology permits while using medium- and high-sulfur coal in an environmentally-acceptable manner; development of the technology enabling coal-oil slurries to be substituted as feedstock for gas or oil-fired combustors; and improvement of the efficiency of present boilers. Compared with conventional coal-fired systems, fluidized-bed combustion systems give higher power generation efficiencies and cleaner exhaust gases, even when burning high-sulfur coals. If the fluidized-bed system is pressurized, additional economies in capital and operating costs may be realized. The benefits from high-pressure combustion are a reduction of furnace size due to decreased gas volume and better sulfur removal. High-pressure combustion, however, requires the development of equipment to clean the hot combustion products to make them suitable for use in power generation turbines. The advanced power systems program is directed toward developing electric power systems capable of operating on coal or coal-derived fuels. These systems involve the use of high temperature gas turbines burning low-Btu gas and turbine systems using inert gases and alkali metal vapors. Some 25 projects in these areas are described, including a brief summary of progress during the quarter. (LTN)

  12. An analysis of markets for small-scale, advanced coal-combustion technology in Spain, Italy, and Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Placet, M.; Gerry, P.A.; Kenski, D.M.; Kern, D.M.; Nehring, J.L.; Szpunar, C.B.

    1989-09-01

    This report discusses the examination of potential overseas markets for using small-scale, US-developed, advanced coal-combustion technologies (ACTs). In previous work, member countries of the Organization for Economic Cooperation and Development (OECD) were rated on their potential for using ACTs through a comprehensive screening methodology. The three most promising OECD markets were found to be Spain, Italy, and Turkey. This report provides in-depth analyses of these three selected countries. First, it addresses changes in the European Community with particular reference to the 1992 restructuring and its potential effect on the energy situation in Europe, specifically in the three subject countries. It presents individual country studies that examine demographics, economics, building infrastructures, and energy-related factors. Potential niches for ACTs are explored for each country through regional analyses. Marketing channels, strategies, and the trading environments in each country are also discussed. The information gathered indicates that Turkey is a most promising market, Spain is a fairly promising market, and Italy appears to be a somewhat limited market for US ACTs. 76 refs., 16 figs., 14 tabs.

  13. Combined-cycle power stations using ``clean-coal-technologies``: Thermodynamic analysis of full gasification vs. fluidized bed combustion with partial gasification

    Energy Technology Data Exchange (ETDEWEB)

    Lozza, G.; Chiesa, P. [Politecnico di Milano, Milan (Italy). Dept. of Energetics; DeVita, L. [Eniricerche, Milan (Italy)

    1994-12-31

    A novel class of power plants for clean conversion of coal into power has been recently proposed, based on the concept of partial coal gasification and fluidized-bed combustion of unconverted char from gasification. This paper focuses on the thermodynamic aspects of these plants, in comparison with full gasification cycles, assessing their performance on the basis of a common advanced power plant technology level. Several plant configurations are considered, including pressurized or atmospheric fluidized-bed, air- or steam-cooled, with different carbon conversion in the gasifier. The calculation method, used for reproducing plant energy balances and for performance prediction, is described in the paper. A complete second-law analysis is carried out, pointing out the efficiency loss breakdown for both technologies. Results show that partial gasification plants can achieve efficiencies consistently higher than IGCC, depending on plant configuration and carbon conversion, making this solution a viable and attractive option for efficient coal utilization.

  14. Combined-cycle power stations using clean-coal technologies: Thermodynamic analysis of full gasification versus fluidized bed combustion with partial gasification

    Energy Technology Data Exchange (ETDEWEB)

    Lozza, G.; Chiesa, P. [Politecnico di Milano, Milan (Italy). Dept. of Energetics; DeVita, L. [Eniricerche, Milan (Italy)

    1996-10-01

    A novel class of power plants for clean conversion of coal into power has been recently proposed, based on the concept of partial coal gasification and fluidized-bed combustion of unconverted char from gasification. This paper focuses on the thermodynamic aspects of these plants, in comparison with full gasification cycles, assessing their performance on the basis of a common advanced power plant technology level. Several plant configurations are considered, including pressurized or atmospheric fluidized-bed, air- or steam-cooled, with different carbon conversion in the gasifier. The calculation method, used for reproducing plant energy balances and for performance prediction, is described in the paper. A complete second-law analysis is carried out, pointing out the efficiency loss breakdown for both technologies. Results show that partial gasification plants can achieve efficiencies consistently higher than IGCC, depending on plant configuration and carbon conversion, making this solution a viable and attractive option for efficient coal utilization.

  15. Study on combustion characteristics of blended coals

    Energy Technology Data Exchange (ETDEWEB)

    Li Yonghua; Wang Chunbo; Chen Hongwei [North China Electric Power University, Baoding (China)

    2007-02-15

    Power plants in China have to burn blended coal instead of one specific coal for a variety of reasons. So it is of great necessity to investigate the combustion of blended coals. Using a test rig with a capacity of 640 MJ/h with an absolute milling system and flue gas online analysis system, characteristics such as burnout, slag, and pollution of some blended coals were investigated. The ratio of coke and slag as a method of distinguishing coal slagging characteristic was introduced. The results show that the blending of coal has some effect on NOx but there is no obvious rule. SOx emission can be reduced by blending low sulfur coal.

  16. Measurement and simulation of swirling coal combustion

    Institute of Scientific and Technical Information of China (English)

    Liyuan Hu; Lixing Zhou; Yonghao Luo; Caisong Xu

    2013-01-01

    Particle image velocimetry (PIV),thermocouples and flue gas analyzer are used to study swirling coal combustion and NO formation under different secondary-air ratios.Eulerian-Lagrangian large-eddy simulation (LES) using the Smagorinsky-Lilly sub-grid scale stress model,presumed-PDF fast chemistry and eddy-break-up (EBU) gas combustion models,particle devolatilization and particle combustion models,are simultaneously used to simulate swirling coal combustion.Statistical LES results are validated by measurement results.Instantaneous LES results show that the coherent structures for swirling coal combustion are stronger than those for swirling gas combustion.Particles are shown to concentrate along the periphery of the coherent structures.Combustion flame is located in the high vorticity and high particle concentration zones.Measurement shows that secondary-air ratios have little effect on final NO formation at the exit of the combustor.

  17. Recycling of coal combustion wastes.

    Science.gov (United States)

    Oz, Derya; Koca, Sabina; Koca, Huseyin

    2009-05-01

    The separation of unburned carbon from coal-fired power plant bottom ashes was conducted in order to increase the possibility of the recycling of coal combustion wastes. A two-stage flotation technique was used for this study. In the rougher flotation experiments the amounts of collector, dispersant and frother, pulp density, pH, particle size distribution, flotation time and flotation temperature were tested as variables. After rougher flotation experiments, at optimum conditions, the carbon content of the concentrate increased from 13.85 to 51.54% at a carbon recovery of 54.54%. Under the same conditions, the carbon content was reduced to 4.54% at a weight yield of over 80% in the tailings fraction. This fraction meets the industrial specifications and can be utilized as a cement additive. After the cleaner flotation experiment the carbon content of the product was enhanced to 64.81% with a 52.16% carbon recovery. This fraction can be blended back into the coal feed to the power plant boilers.

  18. Coal Combustion Science quarterly progress report, April--June 1990

    Energy Technology Data Exchange (ETDEWEB)

    Hardesty, D.R. (ed.); Baxter, L.L.; Fletcher, T.H.; Mitchell, R.E.

    1990-11-01

    This document provides a quarterly status report of the Coal Combustion Science Program that is being conducted at the Combustion, Research Facility, Sandia National Laboratories, Livermore, California. Coal devolatilization, coal char combustion, and fate of mineral matter during coal combustion. 56 refs., 25 figs., 13 tabs.

  19. Atmospheric fluidized bed coal combustion research, development and application

    CERN Document Server

    Valk, M

    1994-01-01

    The use of fluidized bed coal combustion technology has been developed in the past decade in The Netherlands with a view to expanding the industrial use of coal as an energy supply. Various research groups from universities, institutes for applied science and from boiler industries participated and contributed to this research area. Comprehensive results of such recent experimentation and development work on atmospheric fluidized bed combustion of coal are covered in this volume. Each chapter, written by an expert, treats one specific subject and gives both the theoretical background as well a

  20. Analysis of combustion efficiency in CFB coal combustors

    Energy Technology Data Exchange (ETDEWEB)

    Afsin Gungor [Nigde University, Nigde (Turkey). Department of Mechanical Engineering, Faculty of Engineering and Architecture

    2008-06-15

    Fluidized bed technology is well known for its high combustion efficiency and is widely used in coal combustion. In this study, the combustor efficiency has been defined and investigated for CFB coal combustor based on the losses using a dynamic 2D model. The model is shown to agree well with the published data. The effect of operating parameters such as excess air ratio, bed operational velocity, coal particle diameter and combustor load and the effect of design variables such as bed height and bed diameter on the mean bed temperature, the overall CO emission and the combustion efficiency are analyzed for the small-scale of CFBC in the presently developed model. As a result of this analysis, it is observed that the combustion efficiency decreases with increasing excess air value. The combustion efficiency increases with the bed operational velocity. Increasing coal particle size results in higher combustion efficiency values. The coal feed rate has negative effect on the combustion efficiency. The combustor efficiency considerably increases with increasing combustor height and diameter if other parameters are kept unchanged. 46 refs., 16 figs., 6 tabs.

  1. SPONTANEOUS COAL COMBUSTION; MECHANISMS AND PREDICTION.

    Science.gov (United States)

    Herring, James R.; Rich, Fredrick J.

    1983-01-01

    Spontaneous ignition and combustion of coal is a major problem to the coal mining, shipping, and use industries; unintentional combustion causes loss of the resource as well as jeopardy to life and property. The hazard to life is especially acute in the case of underground coal mine fires that start by spontaneous ignition. It is the intention of this research to examine previously suggested causes of spontaneous ignition, to consider new evidence, and to suggest an experimental approach to determine which of these suggested causes is relevant to western U. S. coal. This discussion focuses only on causes and mechanism of spontaneous ignition.

  2. Low NO sub x heavy fuel combustor concept program. Phase 1A: Combustion technology generation coal gas fuels

    Science.gov (United States)

    Sherlock, T. P.

    1982-01-01

    Combustion tests of two scaled burners using actual coal gas from a 25 ton/day fluidized bed coal gasifier are described. The two combustor configurations studied were a ceramic lined, staged rich/lean burner and an integral, all metal multiannual swirl burner (MASB). The tests were conducted over a range of temperature and pressures representative of current industrial combustion turbine inlet conditions. Tests on the rich lean burner were conducted at three levels of product gas heating values: 104, 197 and 254 btu/scf. Corresponding levels of NOx emissions were 5, 20 and 70 ppmv. Nitrogen was added to the fuel in the form of ammonia, and conversion efficiencies of fuel nitrogen to NOx were on the order of 4 percent to 12 percent, which is somewhat lower than the 14 percent to 18 percent conversion efficiency when src-2 liquid fuel was used. The MASB was tested only on medium btu gas (220 to 270 btu/scf), and produced approximately 80 ppmv NOx at rated engine conditions. Both burners operated similarly on actual coal gas and erbs fuel, and all heating values tested can be successfully burned in current machines.

  3. Compilation of Sandia coal char combustion data and kinetic analyses

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, R.E.; Hurt, R.H.; Baxter, L.L.; Hardesty, D.R.

    1992-06-01

    An experimental project was undertaken to characterize the physical and chemical processes that govern the combustion of pulverized coal chars. The experimental endeavor establishes a database on the reactivities of coal chars as a function of coal type, particle size, particle temperature, gas temperature, and gas and composition. The project also provides a better understanding of the mechanism of char oxidation, and yields quantitative information on the release rates of nitrogen- and sulfur-containing species during char combustion. An accurate predictive engineering model of the overall char combustion process under technologically relevant conditions in a primary product of this experimental effort. This document summarizes the experimental effort, the approach used to analyze the data, and individual compilations of data and kinetic analyses for each of the parent coals investigates.

  4. Combustion of Coal/Oil/Water Slurries

    Science.gov (United States)

    Kushida, R. O.

    1982-01-01

    Proposed test setup would measure combustion performance of new fuels by rapidly heating a droplet of coal/oil/water mixture and recording resulting explosion. Such mixtures are being considered as petroleum substitutes in oil-fired furnaces.

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

    Energy Technology Data Exchange (ETDEWEB)

    Brent Marquis

    2007-05-31

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

  6. Comparative Techno-economic assessment of biomass and coal with CCS technologies in a pulverized combustion power plant in the United Kingdom

    OpenAIRE

    Al-Qayim, K.; Nimmo, W.; Pourkashanian, M

    2015-01-01

    The technical performance and cost effectiveness of white wood pellets (WWP) combustion in comparison to three types of coal namely U.S., Russian and Colombian coals are investigated in this study. Post-combustion capture and storage (CCS) namely with amine FG+, and oxy-fuel with carbon capture and storage (oxy-fuel) are applied to a 650 MW pulverized combustion (PC) plant. The impacts of the Renewable Obligation Certificate (ROC) and carbon price (CP) policy in accelerating the CCS deploymen...

  7. Health effects of coal technologies: research needs

    Energy Technology Data Exchange (ETDEWEB)

    1980-09-01

    In this 1977 Environmental Message, President Carter directed the establishment of a joint program to identify the health and environmental problems associated with advanced energy technologies and to review the adequacy of present research programs. In response to the President's directive, representatives of three agencies formed the Federal Interagency Committee on the Health and Environmental Effects of Energy Technologies. This report was prepared by the Health Effects Working Group on Coal Technologies for the Committee. In this report, the major health-related problems associated with conventional coal mining, storage, transportation, and combustion, and with chemical coal cleaning, in situ gasification, fluidized bed combustion, magnetohydrodynamic combustion, cocombustion of coal-oil mixtures, and cocombustion of coal with municipal solid waste are identified. The report also contains recommended research required to address the identified problems.

  8. Review of the AD700 technology: a European route to clean combustion of coal

    Energy Technology Data Exchange (ETDEWEB)

    J. Bugge; S. Kjaer; R. Vanstone; F. Klauke; C. Stolzemberger; F. Bregani; S. Concari [Elsam Engineering (Denmark)

    2005-07-01

    Following the paper presented at CCT2002 Conference dealing with 'Advanced 700{sup o}C PF Power Plant: Start of Phase 2 of the European Project', this paper updates and reviews the status of the AD700 technology being developed in Europe by a group of major manufacturers and utilities, with the contribution of material suppliers, testing labs and research centres. Final results from Phase 1 (1998-2004), supported by European Commission in the frame of 5th Framework Programme, are presented. They can be summarised as following: materials have been identified; thermodynamic cycles have been agreed upon; feasibility studies showed competitiveness; new boiler concepts with reduced amount of super-alloys have been assessed. Progress results from Phase 2 (2002-2005, with expected prolongation until 2007), supported by European Commission in the frame of 6th Framework Programme, will be also presented. They deal with: design and testing of critical components; further studies on innovative design; design of a CTF (Components Test Facility); assessment of a demo plant. The COMTES700 project, supported by both European Commission in the frame of ECSC Programme and utilities belonging to the Emax group, is outlined. It deals with the realisation and testing of the CTF at the Scholven F power station in Germany. 4 refs., 3 figs., 3 tabs.

  9. Innovative Clean Coal Technology (ICCT): 500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. Technical progress report, First quarter 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-31

    This quarterly report discusses the technical progress of an Innovative Clean Coal Technology (ICCT) demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. The project is being conducted at Georgia Power Company`s Plant Hammond Unit 4 located near Rome, Georgia. The primary goal of this project is the characterization of the low NO{sub x} combustion equipment through the collection and analysis of long-term emissions data. A target of achieving fifty percent NO{sub x} reduction using combustion modifications has been established for the project. The project provides a stepwise retrofit of an advanced overfire air (AOFA) system followed by low NO{sub x} burners (LNB). During each test phase of the project, diagnostic, performance, long-term, and verification testing will be performed. These tests are used to quantify the NO{sub x} reductions of each technology and evaluate the effects of those reductions on other combustion parameters such as particulate characteristics and boiler efficiency.

  10. Coal Combustion Products Extension Program

    Energy Technology Data Exchange (ETDEWEB)

    Tarunjit S. Butalia; William E. Wolfe

    2003-12-31

    The primary objective of the CCP Extension Program is to promote the responsible uses of Ohio CCPs that are technically sound, environmentally safe, and commercially competitive. A secondary objective is to assist other CCP generating states (particularly neighboring states) in establishing CCP use programs within their states. The goal of the CCP extension program at OSU is to work with CCP stakeholders to increase the overall CCP state utilization rate to more than 30% by the year 2005. The program aims to increase FGD utilization for Ohio to more than 20% by the year 2005. The increased utilization rates are expected to be achieved through increased use of CCPs for highway, mine reclamation, agricultural, manufacturing, and other civil engineering uses. In order to accomplish these objectives and goals, the highly successful CCP pilot extension program previously in place at the university has been expanded and adopted by the university as a part of its outreach and engagement mission. The extension program is an innovative technology transfer program with multiple sponsors. The program is a collaborative effort between The Ohio State University (College of Engineering and University Extension Service), United States Department of Energy's National Energy Technology Laboratory, Ohio Department of Development's Coal Development Office, and trade associations such as the American Coal Ash Association as well as the Midwest Coal Ash Association. Industry co-sponsors include American Electric Power, Dravo Lime Company, and ISG Resources. Implementation of the proposed project results in both direct and indirect as well as societal benefits. These benefits include (1) increased utilization of CCPs instead of landfilling, (2) development of proper construction and installation procedures, (3) education of regulators, specification-writers, designers, construction contractors, and the public, (4) emphasis on recycling and decrease in the need for landfill

  11. STUDY ON MAJOR FACTORS INFLUENCING SPONTANEOUS COMBUSTION OF COAL

    Institute of Scientific and Technical Information of China (English)

    Deng Jun; Xu Jingcai; Zhang Xinghai

    2000-01-01

    This paper theoretically analyzes major factors influencing spontaneous combustion of coal, such as molecule structure of coal, porosity, temperature, concentration of oxygen, coal thickness, velocity of face advance, and so on; and probes into how they affect the process of spontaneous combustion of coal, which is of momentous significance to predict or control self-ignition of coal.

  12. Health impacts of domestic coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Finkelman, R.B.

    1999-07-01

    The US Environmental Protection Agency (EPA) has concluded that, with the possible exception of mercury, there is no compelling evidence to indicate that emissions from coal-burning electric utility generators cause human health problems. The absence of detectable health problems is in part due to the fact that the coals burned in the US generally contain low to modest concentrations of potentially toxic trace elements and that many coal-burning utilities employ sophisticated pollution control systems that efficiently reduce the emissions of hazardous elements. This is not so in many developing countries, especially in homes where coal is used for heating and cooking. Domestic use of coal can present serious human health problems because the coals are generally mined locally with little regard to their composition and the coals are commonly burned in poorly vented or unvented stoves directly exposing residents to the emissions. In China alone several hundred million people commonly burn raw coal in unvented stoves that permeate their homes with high levels of toxic metals and organic compounds. At least 3,000 people in Guizhou Province in southwest China are suffering from severe arsenic poisoning. The primary source of the arsenic appears to be consumption of chili peppers dried over fires fueled with high-arsenic coal. Coal's in the region contain up to 35,000 ppm arsenic. Chili peppers dried over these high-arsenic coal fires absorb 500 ppm arsenic on average. More than 10 million people in Guizhou Province and surrounding areas suffer from dental and skeletal fluorosis. The excess fluorine is due to eating corn dried over burning briquettes made from high-fluorine coals and high-fluoring clay binders. Polycyclic aromatic hydrocarbons formed during coal combustion are believed to cause or contribute to the high incidence of esophageal and lung cancers in parts of China. Domestic coal combustion has also caused selenium poisoning and possibly mercury

  13. Study on combustion characteristics of blended coals

    Institute of Scientific and Technical Information of China (English)

    LI Yonghua; WANG Chunbo; CHEN Hongwei

    2007-01-01

    Power plants in China have to burn blended coal instead of one specific coal for a variety of reasons.So it is of great necessity to investigate the combustion of blended coals.Using a test rig with a capacity of 640 MJ/h with an absolute milling system and flue gas online analysis system,characteristics such as burnout,slag,and pollution of some blended coals were investigated.The ratio of coke and slag as a method of distinguishing coal slagging characteristic was introduced.The results show that the blending of coal has some effect on NOx but there is no obvious rule.SOx emission can be reduced by blending low sulfur coal.

  14. Co-combustion of agricultural residues with coal in a fluidized bed combustor.

    Science.gov (United States)

    Ghani, W A W A K; Alias, A B; Savory, R M; Cliffe, K R

    2009-02-01

    Power generation from biomass is an attractive technology that utilizes agricultural residual waste. In order to explain the behavior of biomass-fired fluidized bed incinerator, biomass sources from agricultural residues (rice husk and palm kernel) were co-fired with coal in a 0.15m diameter and 2.3m high fluidized bed combustor. The combustion efficiency and carbon monoxide emissions were studied and compared with those for pure coal combustion. Co-combustion of a mixture of biomass with coal in a fluidized bed combustor designed for coal combustion increased combustion efficiency up to 20% depending upon excess air levels. Observed carbon monoxide levels fluctuated between 200 and 900 ppm with the addition of coal. It is evident from this research that efficient co-firing of biomass with coal can be achieved with minimal modifications to existing coal-fired boilers.

  15. Combustion characteristics of coal and refuse from passenger trains.

    Science.gov (United States)

    Fu-min, Ren; Feng, Yue; Ming, Gao; Min, Yu

    2010-07-01

    Refuse from passenger trains is becoming a significant issue with the development of the Chinese railway. Co-firing is regarded as a promising thermal technology, both environmentally and economically, in reducing the quantity of refuse. The co-firing property of passenger train refuse with coal, however, may differ due to the differences in the composition of the refuse. In the present study, combustion properties of refuse from passenger train samples and the mixture of refuse with coal were studied in a tube furnace. Thermo analysis methods, such as thermogravimetry (TG), differential scanning calorimetry (DSC), differential thermal analysis (DTA) and derivative thermogravimetry (DTG) analyses were employed to evaluate combustion performance. We found that the mixture of passenger train refuse and coal at a ratio of 1:1 has a lower ignition and burnout temperature than the coal-only sample. Moreover, refuse from railway passenger trains has more reactive combustion properties than the coal-only sample, and the addition of railway passenger train refuse to coal can promote the reactivity of coal.

  16. Application of the NOx Reaction Model for Development of Low-NOx Combustion Technology for Pulverized Coals by Using the Gas Phase Stoichiometric Ratio Index

    Directory of Open Access Journals (Sweden)

    Kenji Yamamoto

    2011-03-01

    Full Text Available We previously proposed the gas phase stoichiometric ratio (SRgas as an index to evaluate NOx concentration in fuel-rich flames. The SRgas index was defined as the amount of fuel required for stoichiometric combustion/amount of gasified fuel, where the amount of gasified fuel was the amount of fuel which had been released to the gas phase by pyrolysis, oxidation and gasification reactions. In the present study we found that SRgas was a good index to consider the gas phase reaction mechanism in fuel-rich pulverized coal flames. When SRgas < 1.0, NOx concentration was strongly influenced by the SRgas value. NOx concentration was also calculated by using a reaction model. The model was verified for various coals, particle diameters, reaction times, and initial oxygen concentrations. The most important reactions were gas phase NOx reduction reactions by hydrocarbons. The hydrocarbon concentration was estimated based on SRgas. We also investigated the ratio as an index to develop a new low-NOx combustion technology for pulverized coals. We examined the relation between local SRgas distribution in the fuel-rich region in the low-NOx flame and NOx emissions at the furnace exit, by varying burner structures. The relationship between local SRgas value and local NOx concentration was also examined. When a low-NOx type burner was used, the value of SRgas in the flame was readily decreased. When the local SRgas value was the same, it was difficult to influence the local NOx concentration by changing the burner structure. For staged combustion, the most important item was to design the burner structure and arrangement so that SRgas could be lowered as much as possible just before mixing with staged air.

  17. Mineralogy of clean coal combustion by-products

    Institute of Scientific and Technical Information of China (English)

    Ligang Wang; Changhe Chen; Kruse H. Kolker

    2004-01-01

    Coal combustion technologies are changing in order to bum coal more cleanly. Many "clean combustion" and postcombustion technologies are developed to remove SO2 and NOx gases, particulate matter during combustion, or from the flue gases leaving the furnace. This paper focuses on three types of fly ash (flue gas desulfurization (FGD) residuals, atmospheric fluidized bed combustion (AFBC) residuals and sorbent duct injection (SDI) residuals) which produced by "the clean combustion" and postcombustion technologies. The residuals formed by FGD are PCFA (pulverized coal fly ash) grains entrained with reacted and unreacted sorbent and have lower bulk densities than PCFA grains because it contains higher concentrations of calcium and sulfur, and lower concentrations of silicon, aluminum and iron than PCFAs. AFBC residuals consist of spent bed which is a heterogeneous mixture of coarse-grained bed material and irregularly shaped, unfused, spherical PCFAs. The main crystalline phases in AFBC residuals are anhydrite (reacted sorbent), quartz and lime (unreacted sobent), calcite, hematite, periclase, magnetite and feldspars.The residuals produced by SDI contained 65%-70% PCFA with the larger sizes material being irregularly shaped, fused or roughedged. The reaction products of sorbent (portlandite and lime) included calcium sulfate (anhydrite) and calcium sulfate. The chemical properties of these residuals are similar to those of high calcium PCFAs because of the high alkalinity and high pH of these residuals.

  18. Innovative Clean Coal Technology (ICCT): 180 MW demonstration of advanced tangentially-fired combustion techniques for the reduction of nitrogen oxide (NO[sub x]) emissions from coal-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    1992-11-25

    This quarterly report discusses the technical progress of a US Department of Energy (DOE) Innovative Clean Coal Technology (ICCT) Project demonstrating advanced tangentially-fired combustion techniques for the reduction of nitrogen oxide (NO[sub x]) emissions from a coal-fired boiler. The project is being conducted at Gulf Power Company's Plant Lansing Smith Unit 2 located near Panama City, Florida. The primary objective of this demonstration is to determine the long-term effects of commercially available tangentially-fired low NO[sub x] combustion technologies on NO[sub x] emissions and boiler performance. A target of achieving fifty percent NO[sub x] reduction using combustion modifications has been established for the project. The stepwise approach that is being used to evaluate the NO[sub x] control technologies requires three plant outages to successively install the test instrumentation and the different levels of the low NO[sub x] concentric firing system (LNCFS). Following each outage, a series of four groups of tests are performed. These are (1) diagnostic, (2) performance, (3) long-term, and (4) verification. These tests are used to quantify the NO[sub x] reductions of each technology and evaluate the effects of those reductions on other combustion parameters such as particulate characteristics and boiler efficiency. This technical progress report presents the LNCFS Level I short-term data collected during this quarter. In addition, a comparison of all the long-term emissions data that have been collected to date is included.

  19. Innovative Clean Coal Technology (ICCT): 180 MW demonstration of advanced tangentially-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. Technical progress report, second quarter 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-11-25

    This quarterly report discusses the technical progress of a US Department of Energy (DOE) Innovative Clean Coal Technology (ICCT) Project demonstrating advanced tangentially-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from a coal-fired boiler. The project is being conducted at Gulf Power Company`s Plant Lansing Smith Unit 2 located near Panama City, Florida. The primary objective of this demonstration is to determine the long-term effects of commercially available tangentially-fired low NO{sub x} combustion technologies on NO{sub x} emissions and boiler performance. A target of achieving fifty percent NO{sub x} reduction using combustion modifications has been established for the project. The stepwise approach that is being used to evaluate the NO{sub x} control technologies requires three plant outages to successively install the test instrumentation and the different levels of the low NO{sub x} concentric firing system (LNCFS). Following each outage, a series of four groups of tests are performed. These are (1) diagnostic, (2) performance, (3) long-term, and (4) verification. These tests are used to quantify the NO{sub x} reductions of each technology and evaluate the effects of those reductions on other combustion parameters such as particulate characteristics and boiler efficiency. This technical progress report presents the LNCFS Level I short-term data collected during this quarter. In addition, a comparison of all the long-term emissions data that have been collected to date is included.

  20. Innovative clean coal technology: 500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. Final report, Phases 1 - 3B

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-01-01

    This report presents the results of a U.S. Department of Energy (DOE) Innovative Clean Coal Technology (ICCT) project demonstrating advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. The project was conducted at Georgia Power Company`s Plant Hammond Unit 4 located near Rome, Georgia. The technologies demonstrated at this site include Foster Wheeler Energy Corporation`s advanced overfire air system and Controlled Flow/Split Flame low NOx burner. The primary objective of the demonstration at Hammond Unit 4 was to determine the long-term effects of commercially available wall-fired low NOx combustion technologies on NOx emissions and boiler performance. Short-term tests of each technology were also performed to provide engineering information about emissions and performance trends. A target of achieving fifty percent NOx reduction using combustion modifications was established for the project. Short-term and long-term baseline testing was conducted in an {open_quotes}as-found{close_quotes} condition from November 1989 through March 1990. Following retrofit of the AOFA system during a four-week outage in spring 1990, the AOFA configuration was tested from August 1990 through March 1991. The FWEC CF/SF low NOx burners were then installed during a seven-week outage starting on March 8, 1991 and continuing to May 5, 1991. Following optimization of the LNBs and ancillary combustion equipment by FWEC personnel, LNB testing commenced during July 1991 and continued until January 1992. Testing in the LNB+AOFA configuration was completed during August 1993. This report provides documentation on the design criteria used in the performance of this project as it pertains to the scope involved with the low NOx burners and advanced overfire systems.

  1. Coal combustion aerothermochemistry research. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Witte, A.B.; Gat, N.; Denison, M.R.; Cohen, L.M.

    1980-12-15

    On the basis of extensive aerothermochemistry analyses, laboratory investigations, and combustor tests, significant headway has been made toward improving the understanding of combustion phenomena and scaling of high swirl pulverized coal combustors. A special attempt has been made to address the gap between scientific data available on combustion and hardware design and scaling needs. Both experimental and theoretical investigations were conducted to improve the predictive capability of combustor scaling laws. The scaling laws derived apply to volume and wall burning of pulverized coal in a slagging high-swirl combustor. They incorporate the findings of this investigation as follows: laser pyrolysis of coal at 10/sup 6/ K/sec and 2500K; effect of coal particle shape on aerodynamic drag and combustion; effect of swirl on heat transfer; coal burnout and slag capture for 20 MW/sub T/ combustor tests for fine and coarse coals; burning particle trajectories and slag capture; particle size and aerodynamic size; volatilization extent and burnout fraction; and preheat level. As a result of this work, the following has been gained: an increased understanding of basic burning mechanisms in high-swirl combustors and an improved model for predicting combustor performance which is intended to impact hardware design and scaling in the near term.

  2. TOXIC SUBSTANCES FROM COAL COMBUSTION-A COMPREHENSIVE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    C.L. Senior; F. Huggins; G.P. Huffman; N. Shah; N. Yap; J.O.L. Wendt; W. Seames; M.R. Ames; A.F. Sarofim; S. Swenson; J.S. Lighty; A. Kolker; R. Finkelman; C.A. Palmer; S.J. Mroczkowski; J.J. Helble; R. Mamani-Paco; R. Sterling; G. Dunham; S. Miller

    2001-06-30

    The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPs) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the National Energy Technology Laboratory (NETL), the Electric Power Research Institute, and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (UU) and the University of North Dakota Energy and Environmental Research Center (EERC) to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NOx combustion systems, and new power generation plants. Development of ToPEM will be based on PSI's existing Engineering Model for Ash Formation (EMAF). The work discussed in this report covers the Phase II program. Five coals were studied (three in Phase I and two new ones in Phase II). In this work UK has used XAFS and Moessbauer spectroscopies to characterize elements in project coals. For coals, the principal use was to supply direct information about certain hazardous and other key elements (iron) to complement the more complete indirect investigation of elemental modes of occurrence being carried out by colleagues at USGS. Iterative selective leaching using ammonium acetate, HCl, HF, and HNO3, used in conjunction with mineral identification/quantification, and microanalysis of individual mineral grains, has allowed USGS to delineate modes of occurrence for 44 elements. The Phase II coals show rank-dependent systematic differences in trace-element modes of occurrence. The work at

  3. TOXIC SUBSTANCES FROM COAL COMBUSTION-A COMPREHENSIVE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    C.L. Senior; F. Huggins; G.P. Huffman; N. Shah; N. Yap; J.O.L. Wendt; W. Seames; M.R. Ames; A.F. Sarofim; S. Swenson; J.S. Lighty; A. Kolker; R. Finkelman; C.A. Palmer; S.J. Mroczkowski; J.J. Helble; R. Mamani-Paco; R. Sterling; G. Dunham; S. Miller

    2001-06-30

    The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPs) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the National Energy Technology Laboratory (NETL), the Electric Power Research Institute, and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (UU) and the University of North Dakota Energy and Environmental Research Center (EERC) to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NOx combustion systems, and new power generation plants. Development of ToPEM will be based on PSI's existing Engineering Model for Ash Formation (EMAF). The work discussed in this report covers the Phase II program. Five coals were studied (three in Phase I and two new ones in Phase II). In this work UK has used XAFS and Moessbauer spectroscopies to characterize elements in project coals. For coals, the principal use was to supply direct information about certain hazardous and other key elements (iron) to complement the more complete indirect investigation of elemental modes of occurrence being carried out by colleagues at USGS. Iterative selective leaching using ammonium acetate, HCl, HF, and HNO3, used in conjunction with mineral identification/quantification, and microanalysis of individual mineral grains, has allowed USGS to delineate modes of occurrence for 44 elements. The Phase II coals show rank-dependent systematic differences in trace-element modes of occurrence. The work at

  4. Combustion char morphology related to combustion temperature and coal petrography

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, P.; Petersen, H.I.; Thomsen, E. [Geological Survey of Denmark, Copenhagen (Denmark)

    1996-07-01

    Chars produced from different reactors were found to lack consistency of morphological charactersitics. Therefore, the morphology of chars sampled from various laboratory-scale reactors operating at temperatures from 800 to {gt} 1400{degree}C, together with chars collected directly in the flame zone in a full-scale pulverised fuel combustion experiment, was examined. A coal and coal blend dominated by vitrinite-rich microlithotypes together with four coals dominated by inertinite-rich microlithotypes were used to produce the combustion chars. Char samples produced at temperatures above {approximately} 1300{degree}C have a morphotype composition very similar to the composition of the full-scale char samples, whereas the morphotype compositions of those produced at {approximately} 1550{degree}C or lower are significantly different. Correlation between coal petrography and char morphology and determination of char reactivity should thus be attempted only using chars produced at temperatures comparable with those for the intended use of the coal. A clear distinction between the high-temperature char samples (burnout 50-60wt% daf) emerges which is related mainly to the parent coal petrography and probably secondarily to the rank. Vitrite, clarite and vitrinertie V may be correlated with the porous tenuisphere and crassisphere morphotypes, whereas inertite, durite, vitrinertite I, duroclarite and charodurite may be correlated with the crassinetwork-mixed-network-mixed morphotype group. 29 refs., 7 figs., 7 tabs.

  5. COAL COMBUSTION EFFICIENCY IN CFB BOILER

    Institute of Scientific and Technical Information of China (English)

    Hairui Yang; Guangxi Yue

    2005-01-01

    The carbon content in the fly ash from most Chinese circulating fluidized bed (CFB) boilers is much higher than expected, thus directly influencing the combustion efficiency. In the present paper, carbon burnout was investigated both in field tests and laboratory experiments. The effect of coal property, operation condition, gas-solid mixing, char deactivation,residence time and cyclone performance are analyzed seriatim based on large amount of experimental results.A coal index is proposed to describe the coal rank, defined by the ratio of the volatile content to the coal heat value, is a useful parameter to analyze the char burnout. The carbon content in the fly ash depends on the coal rank strongly. CFB boilers burning anthracite, which has low coal index, usually have high carbon content in the fly ash. On the contrary, the CFB boilers burning brown coal, which has high coal index, normally have low carbon content.Poor gas-solid mixing in the furnace is another important reason of the higher carbon content in the fly ash. Increasing the velocity and rigidity of the secondary air could extend the penetration depth and induce more oxygen into the furnace center. Better gas solid mixing will decrease the lean oxygen core area and increase char combustion efficiency.The fine char particles could be divided into two groups according to their reactivity. One group is "fresh" char particles with high reactivity and certain amount of volatile content. The other group of char particles has experienced sufficient combustion time both in the furnace and in the cyclone, with nearly no volatile. These "old" chars in the fly ash will be deactivated during combustion of large coal particles and have very low carbon reactivity. The generated fine inert char particles by attrition of large coal particles could not easily burn out even with the fly ash recirculation. The fraction of large coal particles in coal feed should be reduced during fuel preparation process.The cyclone

  6. Combustion Characteristics of Polyethylene and Coal Powder at High Temperature

    Institute of Scientific and Technical Information of China (English)

    LONG Shi-gang; CAO Feng; WANG Si-wei; SUN Liu-heng; PANG Jian-ming; SUN Yu-ping

    2008-01-01

    To study the combustion characteristics of the polyethylene (PE) particle and coal powder at blast temperature of the blast furnace, the contents of CO and CO2 of off-gas during the combustion of PE particle and coal powder at the 1 200 ℃ and 1 250 ℃ were measured using carbon monoxide and carbon dioxide infrared analyzer, and then the corresponding combustion ratio was calculated. The results showed that when the temperature is high, the combustion speed of PE and coal powder is high and the corresponding combustion ratio is high. Whereas, the combustion speed and ratio of PE are much higher than those of coal powder.

  7. Advanced clean coal utilization technologies

    Energy Technology Data Exchange (ETDEWEB)

    Moritomi, Hiroshi [National Inst. for Resources and Environment, Tsukuba, Ibaraki (Japan)

    1993-12-31

    The most important greenhouse gas is CO{sub 2} from coal utilization. Ways of mitigating CO{sub 2} emissions include the use of alternative fuels, using renewable resources and increasing the efficiency of power generation and end use. Adding to such greenhouse gas mitigation technologies, post combustion control by removing CO{sub 2} from power station flue gases and then storing or disposing it will be available. Although the post combustion control have to be evaluated in a systematic manner relating them to whether they are presently available technology, to be available in the near future or long term prospects requiring considerable development, it is considered to be a less promising option owing to the high cost and energy penalty. By contrast, abatement technologies aimed at improving conversion efficiency or reducing energy consumption will reduce emissions while having their own commercial justification.

  8. Combustion enhancing additives for coal firing

    Energy Technology Data Exchange (ETDEWEB)

    Katherine Le Manquais; Colin Snape; Ian McRobbie; Jim Barker [University of Nottingham, Nottingham (United Kingdom). School of Chemical, Environmental and Mining Engineering (SChEME)

    2007-07-01

    For pulverised fuel (pf) combustion, the level of unburnt carbon in fly ash is now considerably more problematic worldwide than a decade ago, because of the introduction of low NOx burners and the increased level of high inertinite in internationally traded coals. Thus, there is a major opportunity to develop an effective additive to improve carbon burnout and obviate the need for post-treatment of fly ash, which endeavours to meet specifications for filler/building materials applications and thereby avoid landfill. A robust comparison of the reactivity of different coals and their corresponding chars is necessary, in order to estimate the effects of such an additive on pf combustion. Coal chars have been generated on a laboratory scale using thermal gravimetric analysis (TGA) and on a larger scale using a drop tube furnace (DTF), which is more representative of the rapid heating rates and mixing achieved on pf combustion. The TGA results indicate that chars have varying levels of reactivity, dependent on the parent coal properties. When physically mixed with a propriety metal additive, the degree of enhancement to the reactivity of these chars also appeared reliant on the parent coal characteristics. Additionally it was demonstrated that DTF chars, whilst showing similar reactivity trends, are less reactive than the equivalent coal chars produced by the TGA. However, when mixed with the metal additive the DTF chars show a significantly greater improvement in reactivity than their analogous TGA chars, indicating the additive may have the greatest impact on the most unreactive carbon in the coal. 42 refs., 6 figs., 1 tab.

  9. 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.

  10. Stabilization of pulverized coal combustion by plasma assist

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, M.; Maruta, K.; Takeda, K.; Solonenko, O.P.; Sakashita, M.; Nakamura, M. [Akita Prefectural University, Akita (Japan). Faculty of System Science & Technology

    2002-03-01

    Ignition and stabilization of pulverized coal combustion by plasma assist is investigated with a 10 kW plasma torch for three different kinds of coal, such as high, medium and low volatile matter coals. Not only high volatile matter coal but also low quality coal can be successfully burned with plasma assist. Research for volatile component of coal shows that a higher temperature field is necessary to extract the volatile matter from inferior coal, while their compositions are almost the same.

  11. A Reduced Order Model for the Design of Oxy-Coal Combustion Systems

    Directory of Open Access Journals (Sweden)

    Steven L. Rowan

    2015-01-01

    Full Text Available Oxy-coal combustion is one of the more promising technologies currently under development for addressing the issues associated with greenhouse gas emissions from coal-fired power plants. Oxy-coal combustion involves combusting the coal fuel in mixtures of pure oxygen and recycled flue gas (RFG consisting of mainly carbon dioxide (CO2. As a consequence, many researchers and power plant designers have turned to CFD simulations for the study and design of new oxy-coal combustion power plants, as well as refitting existing air-coal combustion facilities to oxy-coal combustion operations. While CFD is a powerful tool that can provide a vast amount of information, the simulations themselves can be quite expensive in terms of computational resources and time investment. As a remedy, a reduced order model (ROM for oxy-coal combustion has been developed to supplement the CFD simulations. With this model, it is possible to quickly estimate the average outlet temperature of combustion flue gases given a known set of mass flow rates of fuel and oxidant entering the power plant boiler as well as determine the required reactor inlet mass flow rates for a desired outlet temperature. Several cases have been examined with this model. The results compare quite favorably to full CFD simulation results.

  12. Coal combustion products. A global perspective

    Energy Technology Data Exchange (ETDEWEB)

    Heidrich, Craig [Ash Development Association Australia, Wollongong (Australia); Feuerborn, Hans-Joachim [European Coal Combustion Products Association, Essen (Germany); Weir, Anne [Association of Canadian Industries Recycling Coal Ash (CIRCA), London (Canada)

    2013-07-01

    Large-scale use of coal in power generation gives rise to significant quantities of coal combustion products (CCP) from which important 'hard won' end use markets have been established. Current global CCP production and utilisation including volume and value of international trade will be discussed. An overview of country-specific classification systems for CCPs will be discussed, moreover the important role of legislation in creating legal certainty for the ongoing investment in CCPs management and market development. (orig.)

  13. Performance of PAHs emission from bituminous coal combustion

    Institute of Scientific and Technical Information of China (English)

    严建华; 尤孝方; 李晓东; 倪明江; 尹雪峰; 岑可法

    2004-01-01

    Carcinogenic and mutagenic polycyclic aromatic hydrocarbons (PAHs) generated in coal combustion have caused great environmental health concern. Seventeen PAHs (16 high priority PAHs recommended by USEPA plus Benzo[e]pyrene) present in five raw bituminous coals and released during bituminous coal combustion were studied. The effects of combustion temperature, gas atmosphere, and chlorine content of raw coal on PAHs formation were investigated. Two additives (copper and cupric oxide) were added when the coal was burned. The results indicated that significant quantities of PAHs were produced from incomplete combustion of coal pyrolysis products at high temperature, and that temperature is an important causative factor of PAHs formation. PAHs concentrations decrease with the increase of chlorine content in oxygen or in nitrogen atmosphere. Copper and cupric oxide additives can promote PAHs formation (especially the multi-ring PAHs) during coal combustion.

  14. Control of combustion area using electrical resistivity method for underground coal gasification

    Institute of Scientific and Technical Information of China (English)

    Selivanova Tatiana; Grebenyuk Igor; Belov Alexey

    2012-01-01

    Underground coal gasification (UCG) is one of the clean technologies to collect heat energy and gases (hydrogen,methane,etc.) in an underground coal seam.It is necessary to further developing environmentally friendly UCG system construction.One of the most important UCG's problems is underground control of combustion area for efficient gas production,estimation of subsidence and gas leakage to the surface.For this objective,laboratory experiments were conducted according to the UCG model to identify the process of combustion cavity development by monitoring the electrical resistivity activity on the coal samples to setup fundamental data for the technology engineering to evaluate combustion area.While burning coal specimens,that had been sampled from various coal deposits,electrical resistivity was monitored.Symmetric four electrodes system (ABMN) of direct and low-frequency current electric resistance method was used.for laboratory resistivity measurement of rock samples.Made research and the results suggest that front-end of electro conductivity activity during heating and combusting of coal specimen depended on heating temperature.Combusting coal electro conductivity has complicated multistage type of change.Electrical resistivity method is expected to be a useful geophysical tool to for evaluation of combustion volume and its migration in the coal seam.

  15. Fundamentals of the physical-chemistry of pulverized coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Lahaye, J.; Prado, G. (eds.)

    1987-01-01

    A total of 20 papers were presented at the conference in seven sessions the major headings of which are: devolatilization, heterogeneous combustion, pollutants in coal combustion, optical diagnostics and transfer to the modelling.

  16. Organic emissions in coal combustion in relation to coal structure and combustion temperature

    Energy Technology Data Exchange (ETDEWEB)

    Bruinsma, O.S.L.; Verhagen, E.J.H.; Moulijn, J.A.

    1985-10-01

    The pulsed combustion of coal has been studied in a small fluidized-bed reactor. The effect of combustion temperature and coal rank on the organic composition of the off-gas was investigated. Results are presented for the combustion of an anthracite, a medium-volatile bituminous coal and a high-volatile bituminous coal at 700, 800 and 900 C. The analytical techniques used include on-line FT-IR, O2 monitoring, FID and off-line GC-MS using Tenax as adsorbent. About 120 hydrocarbons were found, of which over 80% have been identified. Overall combustion characteristics such as oxygen consumption, total amount of unburned hydrocarbons and swelling properties of the coal have been related to the composition of the organic substances in the off-gas. The distribution of the polycyclic aromatics, from benzene to chrysene, and of alkylated derivatives is discussed in detail. Oxygen-containing compounds have also been analysed, although detailed discussion would be premature. 20 references.

  17. 75 FR 64974 - Notice of Data Availability on Coal Combustion Residual Surface Impoundments

    Science.gov (United States)

    2010-10-21

    ... Coal Combustion Residual Surface Impoundments AGENCY: Environmental Protection Agency (EPA). ACTION... of Coal Combustion Residuals from Electric Utilities. The Agency is seeking public comment on how, if...; Disposal of Coal Combustion Residuals From Electric Utilities Docket, Attention Docket ID No.,...

  18. Toxic substances from coal combustion -- A comprehensive assessment

    Energy Technology Data Exchange (ETDEWEB)

    Senior, C.L.; Panagiotou, T.; Huggins, F.E.; Huffman, G.P.; Yap, N.; Wendt, J.O.L.; Seames, W.; Ames, M.R.; Sarofim, A.F.; Lighty, J.; Kolker, A.; Finkelman, R.; Palmer, C.A.; Mroczkowsky, S.J.; Helble, J.J.; Mamani-Paco, R.

    1999-07-30

    The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPs) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the Federal Energy Technology Center (FETC), the Electric Power Research Institute, and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (UU) and the University of North Dakota Energy and Environmental Research Center (EERC) to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NOx combustion systems, and new power generation plants. Development of ToPEM will be based on PSI's existing Engineering Model for Ash Formation (EMAF). This report covers the period from 1 April 1999 to 30 June 1999. During this quarter low temperature ashing and elemental analysis of the three Phase II coals were completed. Results from MIT and USGS are comparable. Plans were made for measurements of loss of trace elements during devolatilization and for single particle combustion studies at the University of Utah. The iodated charcoal trap was tested on coal combustion flue gas and was shown to collect both Hg and Se in from the vapor phase with 100% efficiency. Data from the University of Arizona self-sustained combustor were analyzed from the combustion of three coals: Ohio, Wyodak and Illinois No. 6. Ash size distributions and enrichment factors for selected trace elements were calculated. The correlation between the concentration of the more volatile trace elements in the ash and the

  19. Innovative Clean Coal Technology (ICCT): 500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. Third quarterly technical progress report

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    This quarterly report discusses the technical progress of an Innovative Clean Coal Technology (ICCT) demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. The project provides a stepwise retrofit of an advanced overfire air (AOFA) system followed by low NO{sub x} burners (LNB). During each test phase of the project, diagnostic, performance, long-term, and verification testing will be performed. These tests are used to quantify the NO{sub x} reductions of each technology and evaluate the effects of those reductions on other combustion parameters such as particulate characteristics and boiler efficiency. Baseline, AOFA, LNB, and LNB plus AOFA test segments have been completed. Analysis of the 94 days of LNB long-term data collected show the full-load NO{sub x} emission levels to be approximately 0.65 lb/MBtu with fly ash LOI values of approximately 8 percent. Corresponding values for the AOFA configuration are 0.94 lb/MBtu and approximately 10 percent. For comparison, the long-term full-load, baseline NO{sub x} emission level was approximately 1.24 lb/MBtu at 5.2 percent LOI. Comprehensive testing in the LNB+AOFA configuration indicate that at full-load, NO{sub x} emissions and fly ash LOI are near 0.40 lb/MBtu and 8 percent, respectively. However, it is believed that a substantial portion of the incremental change in NO{sub x} emissions between the LNB and LNB+AOFA configurations is the result of additional burner tuning and other operational adjustments and is not the result of the AOFA system. During this quarter, LNB+AOFA testing was concluded. Testing performed during this quarter included long-term and verification testing in the LNB+AOFA configuration.

  20. Fast Ignition and Stable Combustion of Coarse Coal Particles in a Nonslagging Cyclone Combustor

    Institute of Scientific and Technical Information of China (English)

    BiaoZhou; X.L.Wang; 等

    1995-01-01

    A combustion set-up of an innovative nonalagging cyclone combustor called “Spouting-Cyclone Combustor(SCC)”,,with two-stage combustion,organized in orthogonal vortex flows,was established and the experimental studies on the fast ignition and stable combustion of coarse coal particles in this combustor were carried out.The flame temperature versus ignition time and the practical fast ignition the temperature fields in SCC were obtained.These results whow that it is possible to obtain highly efficient and clean combustion of unground coal particles by using this technology.

  1. Combustion and fuel characterization of coal-water fuels

    Energy Technology Data Exchange (ETDEWEB)

    1989-07-01

    Pittsburgh Energy Technology Center (PETC) of the Department of Energy initiated a comprehensive effort in 1982 to develop the necessary performance and cost data and to assess the commercial viability of coal water fuels (CWFs) as applied to representative utility and industrial units. The effort comprised six tasks beginning with coal resource evaluation and culminating in the assessment of the technical and economic consequences of switching representative commercial units from oil to state-of-the-art CWF firing. Extensive bench, pilot and commercial-scale tests were performed to develop necessary CWF combustion and fireside performance data for the subsequent boiler performance analyses and retrofit cost estimates. This report (Volume 2) provides a review of the fuel selection and procurement activities. Included is a discussion on coal washability, transport of the slurry, and characterization. 20 figs., 26 tabs.

  2. Coal combustion products: trash or treasure?

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, T.

    2006-07-15

    Coal combustion by-products can be a valuable resource to various industries. The American Coal Ash Association (ACAA) collects data on production and uses of coal combustion products (CCPs). 122.5 million tons of CCPs were produced in 2004. The article discusses the results of the ACCA's 2004 survey. Fly ash is predominantly used as a substitute for Portland cement; bottom ash for structural fill, embankments and paved road cases. Synthetic gypsum from the FGD process is commonly used in wallboard. Plant owners are only likely to have a buyer for a portion of their CCPs. Although sale of hot water (from Antelope Valley Station) from condensers for use in a fish farm to raise tilapia proved unviable, the Great Plains Synfuels Plant which manufactures natural gas from lignite produces a wide range of products including anhydrous ammonia, phenol, krypton, carbon dioxide (for enhanced oil recovery), tar oils and liquid nitrogen. ACCA's goal is to educate people about CCPs and how to make them into useful products, and market them, in order to reduce waste disposal and enhance revenue. The article lists members of the ACCA. 2 photos., 1 tab.

  3. Combustion characterization of beneficiated coal-based fuels. Quarterly report No. 17, April--June 1993

    Energy Technology Data Exchange (ETDEWEB)

    Chow, O.K.; Nsakala, N.Y.

    1993-08-01

    Pittsburgh Energy Technology Center of the US Department of Energy has contracted with Combustion Engineering, Inc. (CE) to perform a five-year project on ``Combustion Characterization of Beneficiated Coal-Based Fuels.`` The beneficiated coals are produced by other contractors under the DOE Coal Preparation Program. Several contractor-developed advanced coal cleaning processes are run at pilot-scale cleaning facilities to produce 20-ton batches of fuels for shipment to CE`s laboratory in Windsor, Connecticut. CE then processes the products into either a coal-water fuel (CWF) or a dry microfine pulverized coa1 (DMPC) form for combustion testing. The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of BCFs influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. The technical approach used to develop the technical data includes: bench-scale fuel property, combustion, and ash deposition tests; pilot-scale combustion and ash effects tests; and full-scale combustion tests. During the third quarter of 1993, the following technical progress was made: Completed modeling calculations of coal mineral matter transformations, deposition behavior, and heat transfer impacts of six test fuels; and ran pilot-scale tests of Upper Freeport feed coal, microagglomerate product, and mulled product.

  4. Co-combustion of coal and meat and bone meal

    Energy Technology Data Exchange (ETDEWEB)

    I. Gulyurtlu; D. Boavida; P. Abelha; M.H. Lopes; I. Cabrita [DEECA-INETI, Lisbon (Portugal)

    2005-12-01

    Feeding meat and bone meal (MBM) to cattle, sheep or other animals has been banned within the EU since 1 of July 1994. The quantities to be eliminated are measured in millions of tons. Disposal to landfill is not an option, as simply burying the material cannot destroy any potential bovine spongiform encephalopathy (BSE) pathogens. One disposal option is the co-combustion of coal and MBM, to ensure that any living organism is totally thermally destroyed and at the same time valorising its energetic potential. Fluidised bed co-combustion of MBM is considered a viable technological option as it has the flexibility to burn coal with different materials in an efficient way, at relatively low temperatures (750-850{sup o}C) with lower environmental impact. For this purpose, co-combustion tests of coal and MBM were carried out on a pilot scale FBC, to investigate the implications of the results. This involved the determination of the emissions of pollutants like NOx, N{sub 2}O, VOC, CO{sub 2}, as well as the composition and the valorisation of the ashes produced. The ashes from the bed, the cyclones and the stack were collected and analyzed for biological activity, ecotoxicity, heavy metal concentration and leachability. The results obtained suggest that the ashes were suitable to be deposited in municipal landfills. 23 refs., 10 figs., 10 tabs.

  5. Characterization of Coal Combustion Residues from Electric Utilities Using Wet Scrubbers for Multi-Pollutant Control

    Science.gov (United States)

    This report evaluates changes that may occur to coal combustion residues (CCRs) in response to changes in air pollution control technology at coal-fired power plants, which will reduce emissions from the flue gas stack by transferring pollutants to fly ash and other air pollution...

  6. Energy Saving and Pollution Reducing Effects of Coal Combustion Catalysts

    Institute of Scientific and Technical Information of China (English)

    WU Zenghua; YU Zhiwu; ZHU Wentao; ZHOU Rui

    2001-01-01

    Coal catalytic agents (CCS type) have been prepared to improve coal combustion and reduce air pollution.The energy and pollution reductions resulting from the catalysts have been examined with thermal analysis and chromatography.The CCS agents lower the ignition temperature by 30-80℃ and improve the coal combustion efficiency by 10%-25%.The agents also reduce the release of carbon monoxide,sulfur dioxide,and coal particles to environment.The working mechanisms of the catalysts are discussed in terms of their participation in various physico-chemical processes during combustion.

  7. CO-COMBUSTION OF REFUSE DERIVED FUEL WITH COAL IN A FLUIDISED BED COMBUSTOR

    Directory of Open Access Journals (Sweden)

    W. A. WAN AB KARIM GHANI

    2009-03-01

    Full Text Available Power generation from biomass is an attractive technology which utilizes municipal solid waste-based refused derived fuel. In order to explain the behavior of biomass-fired fluidized bed incinerator, biomass sources from refuse derived fuel was co-fired with coal in a 0.15 m diameter and 2.3 m high fluidized bed combustor. The combustion efficiency and carbon monoxide emissions were studied and compared with those from pure coal combustion. This study proved that the blending effect had increased the carbon combustion efficiency up to 12% as compared to single MSW-based RDF. Carbon monoxide levels fluctuated between 200-1600 ppm were observed when coal is added. It is evident from this research that efficient co-firing of biomass with coal can be achieved with minimum modification of existing coal-fired boilers.

  8. Effects of pyrite on the spontaneous combustion of coal

    Institute of Scientific and Technical Information of China (English)

    Jun Deng; Xiaofeng Ma; Yutao Zhang; Yaqing Li; Wenwen Zhu

    2015-01-01

    Pyrite has a significant effect on the spontaneous combustion of coal. The presence of pyrite can change the propensity of coal towards spontaneous combustion. The influences of various pyrite contents on the parameters of spontaneous combustion, such as index gases, temperature and released heat etc., were investigated in this study. Coal samples with different pyrite contents (0%, 3%, 5%, 7%and 9%) were made by mixing coal and pyrite. The oxidation experiments under temperature-programmed condition were carried out to test the release rate of gaseous oxidation products at different temperatures. Differential scanning calorimeter (DSC) was employed to measure the intensity of heat release during coal oxidation for various pyrite contents. The results indicate that pyrite can nonlinearly accelerate the process of spontaneous combustion. The coal sample with a pyrite content of 5% has the largest CO release rate and oxygen adsorption as well. However, the coal sample with a pyrite content of 7% has the largest rate of heat flow according to the results from the DSC tests. Pyrite contents of 5%–7% in coal has the most significant effects on spontaneous combustion within the range of this study. The conclusions are conducive to the evaluation and control for the spontaneous combustion of coal.

  9. Coal slurry combustion optimization on single cylinder engine

    Energy Technology Data Exchange (ETDEWEB)

    1992-09-01

    Under the sponsorship of the US Department of Energy, Morgantown Energy Technology Center, GE Transportation System has been conducting a proof of concept program to use coal water slurry (CWS) fuel to power a diesel engine locomotive since 1988. As reported earlier [1], a high pressure electronically controlled accumulator injector using a diamond compact insert nozzle was developed for this project. The improved reliability and durability of this new FIE allowed for an improved and more thorough study of combustion of CWS fuel in a diesel engine. It was decided to include a diesel pilot fuel injector in the combustion system mainly due to engine start and low load operation needs. BKM, Inc. of San Diego, CA was contracted to develop the electronic diesel fuel pilot/starting FIE for the research engine. As a result, the experimental combustion study was very much facilitated due to the ability of changing pilot/CWS injection timings and quantities without having to stop the engine. Other parameters studied included combustion chamber configuration (by changing CWS fuel injector nozzle hole number/shape/angle), as well as injection pressure. The initial phase of this combustion study is now complete. The results have been adopted into the design of a 12 cylinder engine FIE, to be tested in 1992. This paper summarizes the main findings of this study.

  10. Slipstream pilot-scale demonstration of a novel amine-based post-combustion technology for carbon dioxide capture from coal-fired power plant flue gas

    Energy Technology Data Exchange (ETDEWEB)

    Krishnamurthy, Krish R. [Linde LLC, Murray Hill, NJ (United States)

    2017-02-03

    Post-combustion CO2 capture (PCC) technology offers flexibility to treat the flue gas from both existing and new coal-fired power plants and can be applied to treat all or a portion of the flue gas. Solvent-based technologies are today the leading option for PCC from commercial coal-fired power plants as they have been applied in large-scale in other applications. Linde and BASF have been working together to develop and further improve a PCC process incorporating BASF’s novel aqueous amine-based solvent technology. This technology offers significant benefits compared to other solvent-based processes as it aims to reduce the regeneration energy requirements using novel solvents that are very stable under the coal-fired power plant feed gas conditions. BASF has developed the desired solvent based on the evaluation of a large number of candidates. In addition, long-term small pilot-scale testing of the BASF solvent has been performed on a lignite-fired flue gas. In coordination with BASF, Linde has evaluated a number of options for capital cost reduction in large engineered systems for solvent-based PCC technology. This report provides a summary of the work performed and results from a project supported by the US DOE (DE-FE0007453) for the pilot-scale demonstration of a Linde-BASF PCC technology using coal-fired power plant flue gas at a 1-1.5 MWe scale in Wilsonville, AL at the National Carbon Capture Center (NCCC). Following a project kick-off meeting in November 2011 and the conclusion of pilot plant design and engineering in February 2013, mechanical completion of the pilot plant was achieved in July 2014, and final commissioning activities were completed to enable start-up of operations in January 2015. Parametric tests were performed from January to December 2015 to determine optimal test conditions and evaluate process performance over a variety of operation parameters. A long-duration 1500-hour continuous test campaign was performed from May to

  11. State-of-the-art combustion controls CO{sub 2} emissions from coal : part 2

    Energy Technology Data Exchange (ETDEWEB)

    Farzan, H.; Vecci, S.; McDonald, D.; McCauley, K [Babcock and Wilcox Canada Ltd., Toronto, ON (Canada); Pranda, P.; Varagani, R.; Gautier, F.; Tranier, J.P.; Perrin, N. [Air Liquide Canada Inc., Montreal, PQ (Canada)

    2007-11-15

    Power plant operators use the cost of electricity (COE) as a way to compare different generating technologies, including those that require investment into costly carbon management. This article addressed issues regarding the goals that management sets and how they are measured in terms of economic profit. It was noted that power companies are not as likely to invest in carbon management technologies until there is assurance that competing power companies will do the same, or until incentives encourage it. A few power companies are well located to provide carbon dioxide for enhanced oil recovery, but others intend to master the technology of carbon management in preparation for a time when it may be a key competitive advantage. This article described key elements of oxy-coal combustion feasibility and competitiveness. This included oxygen production and specification for oxy-coal combustion. It was shown that for oxy-coal combustion plants, the best solution to purify the flue gas from the boiler is a lower temperature partial condensation scheme as soon as oxygen removal is considered. Oxy-coal combustion technology for retrofitting coal-fired boilers was also presented. A Clean Environment Development Facility (CEDF) project in Ohio for oxy-coal combustion was described along with the proposed development of a 300 MWe commercial oxy-coal boiler by SaskPower, Babcock and Wilcox Canada and AL. It was concluded that the ability to capture carbon dioxide from power plants is feasible in advanced modes of current technology and with new technology under development. However, oxy-combustion technology requires introducing new equipment to power plants, such as the air separation unit (ASU) and the carbon dioxide central processing unit (CPU). 1 tab., 5 figs.

  12. Wanted: Clean Coal Burning Technology

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    China is intent on developing clean coal burning technology, an objective it can achieve through installing desulfurization facilities at coal-burning power plants that will control SO2 emissions and environmental pollution. According to kuo Yi, deputy director general of the Department of Science and Technology of the State Environmental Protection Agency, China is a major coal-buming country:

  13. Analysis of coal dust combustion and gasification in the cyclone furnace

    Directory of Open Access Journals (Sweden)

    Zarzycki Robert

    2017-01-01

    Full Text Available This study presents the design and operation of the cyclone furnace fuelled with coal dust. The main function of the furnace is coal dust gasification. The combustible gases that mainly contain CO can be used to feed a pulverized coal-fired boiler. The results of numerical calculations presented in the study demonstrated that cyclone furnace can operate over a wide range of fuel flow rates: from the conditions of coal dust combustion, which ensure maintaining the cyclone furnace in a state of hot reserve to the conditions of coal dust gasification, which allow for production of CO. Gasification process helps control temperature under conditions of elevated oxygen concentration. The results allow for the use of the furnace to improve flexibility and coal dust operation through the reduction in its technological minimum.

  14. Going clean : new technology makes coal greener

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, H.

    2007-09-15

    As a widely distributed and reliable resource, coal has played an important role in industrial development. At a cost of less than US $2.00 per GJ, coal will remain a valuable resource as the demand for energy increases. The science of clean coal technology is proven and applications are being formed, particularly in carbon dioxide sequestration. Examples of clean coal technology include oxy-fuel combustion, amine scrubbing and coal gasification. All these approaches produce energy while emitting CO{sub 2} gas that is relatively pure and can be easily captured for storage, thereby preventing emissions to the atmosphere. The Canadian Clean Power Coalition has determined that coal gasification has considerable potential in Canada, particularly since Alberta sits above some of the largest coal and oil reserves in the world. Gasification involves heating up a coal feedstock at high temperatures and pressure, in the presence of water in the form of steam. Synthesis gas and hydrogen are produced in the process. The produced CO{sub 2} is concentrated in a way that makes it relatively easy to capture and sequester in the earth or used to enhance the recovery of oil from depleted oil wells. In addition to coal, there are numerous other carbon-based materials that can be gasified, including bitumens, bitumen residuals or petroleum coke. Studies have shown that Alberta's sub-bituminous coal is an ideal candidate for gasification. There are industries in Alberta that need hydrogen for feedstock, and the Western Canada Sedimentary Basin provides a vast storage for pure CO{sub 2}. It was concluded that gasification is the only current technology that will have the ability to significantly reduce the amount of greenhouse gases released into the atmosphere from fossil fuels. The greatest challenge is the capital cost of building the coal gasification facilities. 4 figs.

  15. A study on briquetting technology for Vietnamese coal

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Pil Chong; Yang, Jung Il; Hwang, Seon Kook; Cho, Ken Joon; Choi, Yeon Ho; Shin, Hee Young; Kim, Sang Bae; Bae, Kwang Hyun [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1995-12-01

    Vietnam reserves abundant, high quality anthracite resources. Nevertheless, Vietnam is facing with serious problem of deforestation, because most of the people use wood and agricultural waste for the family cooking purpose. In order to improve the problem, Vietnam government has established the National Project (KD-03) for enlargement of utilization of Vietnamese coal and also assigned the Institute of Research on Mining Technology(IRMT) to develop the briquetting technology for the use of Vietnamese coal. In accordance, IRMT prepared a Memorandum of Understanding on development of briquetting technology for Vietnamese coal with KIGAM, which preserve sufficient technical know-how on coal briquetting technology. The objective of this project is to develop briquetting technology of Vietnamese coal for cooking purpose and transfer the developed technology to related industrial sector. Eventually it expects to enlarge utilization of Vietnamese coal, reduce deforestation and increase labour employment. This project studied following items on development of coal briquetting technology for Vietnamese cooking purpose: (1) study on properties of Vietnamese coal, (2) study on briquetting technology of Vietnamese coal, (3) study on combustion of Vietnamese coal briquette, (4) preliminary investigation of coal briquette market for industrial use. Besides cooking purpose of Vietnamese coal briquette, Vietnamese coal is also identified to be utilized for small scale industrial use by preliminary investigation. (author). 9 refs., 30 tabs.

  16. Applications of polymer extrusion technology to coal processing

    Science.gov (United States)

    Lewis, D. W.

    1981-01-01

    Upon heating, many of the middle-aged bituminous coals exhibit a plasticity very similar to polyethylene for a few minutes. Plastic coal can be extruded, pelletized or molded using common plastics technology and equipment. Investigations concerning the plastic state of coals are conducted with the objective to develop techniques which will make useful commercial applications of this property possible. Experiments which show the characteristics of plastic-state coal are discussed, and problems related to a continuous extrusion of coal are considered. Probably the most significant difference between the continuous extrusion of coal and the extrusion of a thermoplastic polymer is that volatiles are continuously being released from the coal. Attention is given to aspects of dragflow, solids feeding, and melt pumping. Application potentials for plastic coal extrusion might be related to coal gasification, direct liquefaction, and coal combustion.

  17. Desulfurization kinetics of coal combustion gases

    Directory of Open Access Journals (Sweden)

    S.R. Bragança

    2003-06-01

    Full Text Available Desulfurization of the gases from coal combustion was studied, using limestone (marble as the sorbent in a fluidized-bed reactor. The kinetic parameter, k, was measured by analyzing the reduction in SO2 emissions in relation to time when a batch of limestone was introduced directly into the combustor chamber. The influence of sorbent composition and particle size was also studied. The CaO content in the limestone was more important than the MgO content. Sorbent particle size showed a strong influence on the reaction time and efficiency of desulfurization. The results of this work prove that marble type is very important in the choice of sorbent for a desulfurization process. A magnesian limestone showed a better performance than a dolomite. Therefore, the magnesian limestone is more efficient for a shorter particle residence time, which is characteristic of the bubbling fluidized bed.

  18. Desulfurization kinetics of coal combustion gases

    Energy Technology Data Exchange (ETDEWEB)

    Braganca, S.R.; Jablonski, A.; Castellan, J.L. [Universidade Federal Rio Grande do Sul, Porto Alegre (Brazil)

    2003-06-01

    Desulfurization of the gases from coal combustion was studied, using limestone (marble) as the sorbent in a fluidized-bed reactor. The kinetic parameter, k, was measured by analyzing the reduction in SO{sub 2} emissions in relation to time when a batch of limestone was introduced directly into the combustor chamber. The influence of sorbent composition and particle size was also studied. The CaO content in the limestone was more important than the MgO content. Sorbent particle size showed a strong influence on the reaction time and efficiency of desulfurization. The results of this work prove that marble type is very important in the choice of sorbent for a desulfurization process. A magnesian limestone showed a better performance than a dolomite. Therefore, the magnesian limestone is more efficient for a shorter particle residence time, which is characteristic of the bubbling fluidized bed.

  19. Thermally induced structural changes in coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Flagan, R.C.; Gavalas, G.R.

    1992-01-01

    The effects of the temperature-time history during coal devolitization and oxidation on the physical properties and the reactivity of resulting char were studied experimentally for temperatures and residence times typical of pulverized combustion. Experiments were also carried out at somewhat lower temperatures and correspondingly longer residence times. An electrically heated laminar flow reactor was used to generate char and measure the rates of oxidation at gas temperatures about 1600K. Partially oxidized chars were extracted and characterized by gas adsorption and mercury porosimetry, optical and scanning electron microscopy, and oxidation in a thermogravimetric analysis system (TGA). A different series of experiments was conducted using a quadrople electrodynamic balance. Single particles were suspended electrodynamically and heated by an infrared laser in an inert or oxygen-containing atmosphere. During the laser heating, measurements were taken of particle mass, size/shape, and temperature.

  20. Application and Operational Maintenance Experience of Plasma Pulverized Coal Ignition Combustion Technology%等离子煤粉点火燃烧技术的应用及运维经验

    Institute of Scientific and Technical Information of China (English)

    刘俊臻

    2012-01-01

    介绍了交流等离子煤粉点火系统的工作原理、点火燃烧器功能、点火燃烧机理以及在上海吴泾热电厂2台1125t/h锅炉上的应用情况。总结了等离子煤粉点火装置和稳燃系统的安装、调试与日常运维经验。实践表明,等离子煤粉点火技术是一种节能、环保、快速升负荷的技术。锅炉点火燃油零消耗,既提高了煤粉燃烧的经济性,又减少了燃煤电厂的烟尘排放;既改善了厂区周边环境,又降低了生产成本。交流等离子煤粉点火系统的应用,可以获得较好的经济及社会效益。%The essay introduces operational principle of alternating plasma pulverized coal ignition system, the function of ignition burner, mechanization of ignition combustion and the application of plasma pulverized coal ignition combustion technology on two 1 125 t/h boilers in Shanghai Wujing Thermal Power Plant. It also makes a summary of installation, debugging and routine operational maintenance experience for plasma pulverized coal ignition device and stabilized combustion system. The practice proves that plasma pulverized coal ignition technology is a new technology with conservation of energy, environmental protection and quick power increasing. With ignition fuel oil zero consumption, it not only raises economical efficiency of pulverized coal burning, but also reduces smoke dust discharging in coal fired power plant, and improves power plant's surroundings as well as lowers the production cost effectively. The application of alternating plasma pulverized coal ignition system brings better economic and social benefits.

  1. Carbon dioxide from coal combustion: Variation with rank of US coal

    Science.gov (United States)

    Quick, J.C.; Glick, D.C.

    2000-01-01

    Carbon dioxide from combustion of US coal systematically varies with ASTM rank indices, allowing the amount of CO2 produced per net unit of energy to be predicted for individual coals. No single predictive equation is applicable to all coals. Accordingly, we provide one equation for coals above high volatile bituminous rank and another for lower rank coals. When applied to public data for commercial coals from western US mines these equations show a 15% variation of kg CO2 (net GJ)-1. This range of variation suggests reduction of US CO2 emissions is possible by prudent selection of coal for combustion. Maceral and mineral content are shown to slightly affect CO2 emissions from US coal. We also suggest that CO2 emissions increased between 6 and 8% in instances where Midwestern US power plants stopped burning local, high-sulfur bituminous coal and started burning low-sulfur, subbituminous C rank coal from the western US.

  2. Approximate-analytical study on thermal preparation and combustion of a coal particle

    Energy Technology Data Exchange (ETDEWEB)

    Salomatov, V.V. [SB RAS, Novosibirsk (Russian Federation). Inst. of Thermophysics; Enkhjargal, Kh. [Mongolian Univ. of Science and Technology, Ulaanbaatar (Mongolia)

    2013-07-01

    The main amount of heat and electricity in the world is produced with application of coal. Following development of power engineering plans application of low-grade coals, including those of new deposits (Salomatov VV, Nature conservation technologies at thermal and atomic power plants, Novosibirsk, NSTU, 2006). Massive Shive-Ovoos open-cast is among such low developed deposits of Mongolia. This deposit requires a set of investigations on thermal preparation and combustion of coal, aimed at extensive and efficient energy utilization. Calculation of flame combustion of coals is based on dependences, which determine the whole combustion process of separate coal particles. For particles of natural coals these processes include complex transformations of organic and mineral parts of coal matrix, heating, devolatization, ignition and burning of coke residue. Such detailed elaboration requires complex physical and mathematical simulation. Five successive stages of thermal preparation and combustion of a coal particle with initial humidity and ash content were distinguished by experimental results: 1. Heating. The particle is heated; the temperature increases, and the mass stays constant. 2. Drying. Liquid inside a wet particle evaporates and mass reduces. 3. Devolatization. 4. Ignition of slightly dried carbon layer by fuel gases. Residual moisture is still kept in the particle. 5. Burning. Two successive conditions are considered: 1. simultaneous burning of dried carbon layer and evaporation; 2. burning of absolutely dry coke residue.

  3. Effect of oxydesulphurization on the combustion characteristics of coal

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kucukbayrak, S. [Technical University of Istanbul, Istanbul (Turkey). Dept. of Chemical Engineering

    1997-06-01

    Desulphurization of a Turkish lignite by oxydesulphurization using dilute alkaline solutions, obtained by the extraction of fly ash with water, was carried out under 0-1.5 MPa partial pressure of oxygen at temperatures between 403 and 498 K for 30-90 min time intervals. The combustion characteristics of original and desulphurized lignite samples are compared using TGA. DTG curves were derived and the effects of desulphurization conditions such as temperature, partial pressure of oxygen and time on coal reactivity were studied. Ignition temperature, maximum combustion rate, combustion period, and the end temperature of combustion were considered. Relations between coal reactivity and removals of sulphur and ash contents were also studied.

  4. MECHANISMS AND OPTIMIZATION OF COAL COMBUSTION

    Energy Technology Data Exchange (ETDEWEB)

    Kyriacos Zygourakis

    2000-10-31

    The completed research project has made some significant contributions that will help us meet the challenges outlined in the previous section. One of the major novelties of our experimental approach involves the application of video microscopy and digital image analysis to study important transient phenomena (like particle swelling and ignitions) occurring during coal pyrolysis and combustion. Image analysis was also used to analyze the macropore structure of chars, a dominant factor in determining char reactivity and ignition behavior at high temperatures where all the commercial processes operate. By combining advanced experimental techniques with mathematical modeling, we were able to achieve the main objectives of our project. More specifically: (1) We accurately quantified the effect of several important process conditions (like pyrolysis heating rate, particle size, heat treatment temperature and soak time) on the combustion behavior of chars. These measurements shed new light into the fundamental mechanisms of important transient processes like particle swelling and ignitions. (2) We developed and tested theoretical models that can predict the ignition behavior of char particles and their burn-off times at high temperatures where intraparticle diffusional limitations are very important.

  5. Combustion and economics of coal slurry fuels: a look at coal-fuel oil slurries

    Energy Technology Data Exchange (ETDEWEB)

    Murayama, T.; Matsuoka, H.

    1984-01-01

    With the aim of reducing dependence on petroleum, research has been going ahead into the development of various alternative fuels. Of these, coal slurry fuels are regarded as being first in line for commercialization. The authors discuss the combustion of coal-oil fuels. The combustion of fuel oil, pulverized coal and coal-water slurry is also examined. In each case, combustion properties and associated problems are discussed. Finally, the economics of these fuels are examined and trends in research and development surveyed. 23 references.

  6. NOx EMISSIONS PRODUCED WITH COMBUSTION OF POWDER RIVER BASIN COAL IN A UTILITY BOILER

    Energy Technology Data Exchange (ETDEWEB)

    John S. Nordin; Norman W. Merriam

    1997-04-01

    The objective of this report is to estimate the NOx emissions produced when Powder River Basin (PRB) coal is combusted in a utility boiler. The Clean Air Act regulations specify NOx limits of 0.45 lb/mm Btu (Phase I) and 0.40 lb/mm Btu (Phase II) for tangentially fired boilers, and 0.50 lb/mm 13tu (Phase II) and 0.46 lb/mm Btu (Phase II) for dry-bottom wall-fired boilers. The Clean Air Act regulations also specify other limits for other boiler types. Compliance for Phase I has been in effect since January 1, 1996. Compliance for Phase II goes into effect on January 1, 2000. Emission limits are expressed as equivalent NO{sub 2} even though NO (and sometimes N{sub 2}O) is the NOx species emitted during combustion. Regulatory agencies usually set even lower NOx emission limits in ozone nonattainment areas. In preparing this report, Western Research Institute (WRI) used published test results from utilities burning various coals, including PRB coal, using state-of-the art control technology for minimizing NOx emissions. Many utilities can meet Clean Air Act NOx emission limits using a combination of tight combustion control and low-NOx burners and by keeping furnaces clean (i.e., no slag buildup). In meeting these limits, some utilities also report problems such as increased carbon in their fly ash and excessive furnace tube corrosion. This report discusses utility experience. The theory of NOx emission formation during coal combustion as related to coal structure and how the coal is combusted is also discussed. From this understanding, projections are made for NOx emissions when processed PRB coal is combusted in a test similar to that done with other coals. As will be shown, there are a lot of conditions for achieving low NOx emissions, such as tight combustion control and frequent waterlancing of the furnace to avoid buildup of deposits.

  7. Environmental issues affecting clean coal technology deployment

    Energy Technology Data Exchange (ETDEWEB)

    Miller, M.J. [Electric Power Research Inst., Palo Alto, CA (United States)

    1997-12-31

    The author outlines what he considers to be the key environmental issues affecting Clean Coal Technology (CCT) deployment both in the US and internationally. Since the international issues are difficult to characterize given different environmental drivers in various countries and regions, the primary focus of his remarks is on US deployment. However, he makes some general remarks, particularly regarding the environmental issues in developing vs. developed countries and how these issues may affect CCT deployment. Further, how environment affects deployment depends on which particular type of clean coal technology one is addressing. It is not the author`s intention to mention many specific technologies other than to use them for the purposes of example. He generally categorizes CCTs into four groups since environment is likely to affect deployment for each category somewhat differently. These four categories are: Precombustion technologies such as coal cleaning; Combustion technologies such as low NOx burners; Postcombustion technologies such as FGD systems and postcombustion NOx control; and New generation technologies such as gasification and fluidized bed combustion.

  8. Methodology for Evaluating Encapsulated Beneficial Uses of Coal Combustion Residuals

    Science.gov (United States)

    The primary purpose of this document is to present an evaluation methodology developed by the EPA for making determinations about environmental releases from encapsulated products containing coal combustion residuals.

  9. EXPERIMENTAL STUDY ON HORIZONTAL COMBUSTION TECHNIQUE FOR BITUMINOUS COAL BRIQUET

    Institute of Scientific and Technical Information of China (English)

    路春美; 程世庆; 邵延玲; 张晔

    1997-01-01

    Through a lot of experiments, a new kind of stove using horizontal combustion technique for bituminous coal briquet has been developed. Making use of this stove, studies have been made on burning process of bituminous coal briquet, distribution of temperature field in the stove, the regularities of evolution and combustion of volatile matter, the burning rate and efficiency of bituminous coal briquet, characteristics of fire-sealing and sulfur-retention. The results show that, with the technique, some achievements can be obtained in combustion of bituminous coal briquet, such as lower pollution that the flue gas black degree is below 0.5R and dust concentration is below 90mg/m3 . The stove's combustion efficiency reaches 90%, sulfur fixing efficiency is 60%, and CO concentration is decreased by 40% compared with other traditional stoves. With so many advantages, the stove can be used extensively in civil stoves and smaller industrial boilers.

  10. Pulverized coal torch combustion in a furnace with plasma-coal system

    Science.gov (United States)

    Messerle, V. E.; Ustimenko, A. B.; Askarova, A. S.; Nagibin, A. O.

    2010-09-01

    Combustion of a pulverized coal torch has been numerically simulated on the basis of the equations of multicomponent turbulent two-phase flows. The results of three-dimensional simulation of conventional and plasma activated coal combustion in a furnace are presented. Computer code Cinar ICE was verified at coal combustion in the experimental furnace with thermal power of 3 MW that was equipped with plasma-fuel system. Operation of the furnace has been studied at the conventional combustion mode and with plasma activation of coal combustion. Influence of plasma activation of combustion on thermotechnical characteristics of the torch and decrease of carbon loss and nitrogen oxides concentration at the furnace outlet has been revealed.

  11. EVALUATION OF BROWN COAL SPONTANEOUS COMBUSTION AND SOURCES GENESIS PROGNOSES

    Directory of Open Access Journals (Sweden)

    Vlastimil MONI

    2014-10-01

    Full Text Available This article presents summarizing information about the solution of partial part of research problem of prognoses of deposited brown coal spontaneous combustion sources genesis as a part of project TA01020351 – program ALFA. We will gradually describe the results of long term measurements carried out on selected brown coal heaps realized from 2011 to 2013. The attention is devoted to characterization of key parameters. These parameters influence the genesis of combustion. The second problem is the comparison of results of thermal imaging with laboratory results of gas and coal samples sampled in situ, with the influence of atmospheric conditions (insolation, aeration, rainfall, atmospheric pressure changes etc., with influence of coal mass degradation, physical and chemical factors and another failure factors to brown coal spontaneous combustion processes.

  12. Advanced coal-fueled gas turbine systems: Subscale combustion testing. Topical report, Task 3.1

    Energy Technology Data Exchange (ETDEWEB)

    1993-05-01

    This is the final report on the Subscale Combustor Testing performed at Textron Defense Systems` (TDS) Haverhill Combustion Laboratories for the Advanced Coal-Fueled Gas Turbine System Program of the Westinghouse Electric Corp. This program was initiated by the Department of Energy in 1986 as an R&D effort to establish the technology base for the commercial application of direct coal-fired gas turbines. The combustion system under consideration incorporates a modular staged, rich-lean-quench, Toroidal Vortex Slogging Combustor (TVC) concept. Fuel-rich conditions in the first stage inhibit NO{sub x} formation from fuel-bound nitrogen; molten coal ash and sulfated sorbent are removed, tapped and quenched from the combustion gases by inertial separation in the second stage. Final oxidation of the fuel-rich gases, and dilution to achieve the desired turbine inlet conditions are accomplished in the third stage, which is maintained sufficiently lean so that here, too, NO{sub x} formation is inhibited. The primary objective of this work was to verify the feasibility of a direct coal-fueled combustion system for combustion turbine applications. This has been accomplished by the design, fabrication, testing and operation of a subscale development-type coal-fired combustor. Because this was a complete departure from present-day turbine combustors and fuels, it was considered necessary to make a thorough evaluation of this design, and its operation in subscale, before applying it in commercial combustion turbine power systems.

  13. Advanced coal-fueled gas turbine systems: Subscale combustion testing. Topical report, Task 3.1

    Energy Technology Data Exchange (ETDEWEB)

    1993-05-01

    This is the final report on the Subscale Combustor Testing performed at Textron Defense Systems` (TDS) Haverhill Combustion Laboratories for the Advanced Coal-Fueled Gas Turbine System Program of the Westinghouse Electric Corp. This program was initiated by the Department of Energy in 1986 as an R&D effort to establish the technology base for the commercial application of direct coal-fired gas turbines. The combustion system under consideration incorporates a modular staged, rich-lean-quench, Toroidal Vortex Slogging Combustor (TVC) concept. Fuel-rich conditions in the first stage inhibit NO{sub x} formation from fuel-bound nitrogen; molten coal ash and sulfated sorbent are removed, tapped and quenched from the combustion gases by inertial separation in the second stage. Final oxidation of the fuel-rich gases, and dilution to achieve the desired turbine inlet conditions are accomplished in the third stage, which is maintained sufficiently lean so that here, too, NO{sub x} formation is inhibited. The primary objective of this work was to verify the feasibility of a direct coal-fueled combustion system for combustion turbine applications. This has been accomplished by the design, fabrication, testing and operation of a subscale development-type coal-fired combustor. Because this was a complete departure from present-day turbine combustors and fuels, it was considered necessary to make a thorough evaluation of this design, and its operation in subscale, before applying it in commercial combustion turbine power systems.

  14. Production of Indigenous and Enriched Khyber Pakhtunkhwa Coal Briquettes: Combustion and Disintegration Strength Analysis

    Directory of Open Access Journals (Sweden)

    Unsia Habib

    2013-06-01

    Full Text Available Khyber Pakhtun Khwa province of Pakistan has considerable amounts of low ranked coal. However, due to the absence of any centrally administered power generation system there is a need to explore indigenous methods for effectively using this valuable energy resource. In the present study an indigenous coal briquetting technology has been developed and evaluated in terms of combustion characteristics such as moisture content, volatile matter, ash, fixed carbon and calorific value of the resulting coal briquette and disintegration strength using polyvinyl acetate (PVA in combination with calcium carbonate (sample no 3 with highest disintegration strength value of 2059N. Comparison of test samples with the commercially available coal briquettes revealed improved combustion characteristics for the PVA bonded (sample no 1 and 5 coal briquettes having higher fixed carbon content and calorific value, lower ash contents as well as lower initial ignition time.

  15. Prevention of spontaneous combustion in coal stockpiles : Experimental results in coal storage yard

    NARCIS (Netherlands)

    Fierro, V.; Miranda, J.L.; Romero, C.; Andrés, J.M.; Arriaga, A.; Schmal, D.; Visser, G.H.

    1999-01-01

    The spontaneous ignition of coal stockpiles is a serious economic and safety problem. This paper deals with oxidation and spontaneous combustion of coal piles laid in coal storage yard and the measures to avoid the heat losses produced. Investigations on self heating were carried out with five test

  16. Prevention of spontaneous combustion in coal stockpiles : Experimental results in coal storage yard

    NARCIS (Netherlands)

    Fierro, V.; Miranda, J.L.; Romero, C.; Andrés, J.M.; Arriaga, A.; Schmal, D.; Visser, G.H.

    1999-01-01

    The spontaneous ignition of coal stockpiles is a serious economic and safety problem. This paper deals with oxidation and spontaneous combustion of coal piles laid in coal storage yard and the measures to avoid the heat losses produced. Investigations on self heating were carried out with five test

  17. Atmospheric emission of mercury due to combustion of steam coal and domestic coal in China

    Science.gov (United States)

    Wang, Shaobin; Luo, Kunli

    2017-08-01

    To study the mercury emission due to the combustion of steam coal and domestic coal in China, we analyzed the mercury contents of coal, fly ash, bottom ash and sluicing water in thermal power plants, steam boilers as well as domestic coal-stoves, in Shaanxi, Shanxi, Shandong and Yunnan Provinces. This study conduct an estimate of the Hg emission rates from steam coal and domestic coal combustion based on the method of mass distribution ratio of fly ash and bottom ash. The results show that the Hg emission rate of coal combustion in thermal power plants is about 50.21% (electrostatic precipitators + wet flue gas desulfurization), and that in heating boilers is about 67.23%, and 92.28% in industrial boilers without flue gas desulphurisation equipment. Furthermore, Hg emission rate is 83.61% due to domestic coal combustion in coal-stoves. The Hg emission amount into the atmosphere from power and heat generation, industrial boilers, domestic coal-stoves and spontaneous combustion of coal gangue is roughly estimated to be 133 ± 4, 100 ± 17, 11 ± 0.1 and 47 ± 26 tons in China in 2014, respectively, and the total Hg emission amount from this paper is estimated at 292 tons. The trends of Hg emission in China from 1991 to 2014 show an accelerating growth after 2002. The proportion of mercury emission due to thermal power, heating generation and industrial energy utilization continuously increased. The atmospheric emission of mercury due to combustion of steam coal, domestic coal and coal gangue accounts nearly 50% in total anthropogenic Hg emissions in China, indicating one of the largest sources of Hg emission in China which should draw more public and scientific attention in the future.

  18. Innovative clean coal technology (ICCT): 500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO sub x ) emissions from coal-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    1991-09-13

    The major objectives of the project are to: (1) demonstrate the performance of three combustion NO{sub x} control technologies; (2) determine the short-term NO{sub x} emission trends for each of the operating configurations; (3) determine the dynamic long-term NO{sub x} emission characteristics for each of the operating configurations using sophisticated statistical techniques; (4) evaluate progressive cost-effectiveness (i.e., dollars per ton of NO{sub x} removed) of the low NO{sub x} combustion technologies tested; and (5) determine the effects on other combustion parameters (e.g., CO production, carbon carry-over, particulate characteristics) of applying the low NO{sub x} combustion technologies. (VC)

  19. The Production and Release of CFCs from Coal Combustion

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The destruction of the ozone layer in the atmosphere caused by industrially synthesized CFCs has aroused greatest concerns from the international society, but the CFCs formed from burning of coal containing fluorine have not been recognized by the world yet. In the present study, we condensed the gas through cold traps and used the GC-MS to measure the gas composition, and found that the content of CFC-12 in the smog from coal combustion was significantly higher than the background value of the local atmosphere. This proves that CFC-12 is formed in the process of coal combustion. This paper discusses a new source of non-synthesized CFCs.

  20. Isotopic signature of atmospheric phosphate emitted from coal combustion

    Science.gov (United States)

    Weinberger, Roi; Weiner, Tal; Angert, Alon

    2016-07-01

    Atmospheric deposition of phosphorus (P) serves as an important nutrient input for many terrestrial, marine and freshwater ecosystems, influencing their biogeochemistry and primary production. Fossil fuel combustion, principally coal, is estimated to be a major source of atmospheric-P in industrialized regions. In this research, we aim to find a distinct isotopic signature for fly coal ash, the by-product of coal combustion that is emitted to the atmosphere. This signature could be used to identify coal's contribution to atmospheric-P. For this aim, ten fly coal ash samples from different coal sources, collected by power station filters, were analyzed for P concentrations and stable oxygen isotopic composition (δ18OP). Two inorganic phosphate fractions were analyzed: HCl-extractable and resin-extractable (bioavailable P). High HCl-P concentrations of up to 3500 μg P/g ash were found with a distinct δ18OP range of 17.1-20.5‰. The resin-P concentrations were substantially lower (biosphere since these combustion products likely acidify in the atmosphere to become bioavailable. This is also supported by our finding that smaller particles, which are more indicative of the particles actually emitted to the atmosphere, are significantly P-richer. Natural dust sources' δ18OP overlap fly ash's range, complicating the assessment of coal's contribution. Nonetheless, our results provide a new tool for identification of fossil fuel combustion sources in local and global atmospheric P deposition.

  1. State-of-the-art combustion controls CO{sub 2} emissions from coal : part 1

    Energy Technology Data Exchange (ETDEWEB)

    Farzan, H.; Vecci, S.; McDonald, D.; McCauley, K. [Babcock and Wilcox Canada Ltd., Toronto, ON (Canada); Pranda, P.; Varagani, R.; Gautier, F.; Tranier, J.P.; Perrin, N. [Air Liquide Canada Inc., Montreal, PQ (Canada)

    2007-10-15

    This article provided highlights of a pilot-scale oxy coal combustion experiment for new and retrofitted boiler applications. The oxy-coal combustion technology was assessed with supercritical (SC) and ultra-supercritical (USC) steam cycles. The study was performed on bituminous coal at a 1.5 MWth pilot plant. Engineering and economic evaluations were used to demonstrate that oxy-coal combustion is less expensive than other technologies. A design and cost estimation of an oxy-coal and PC boiler was conducted to evaluate a regulatory design basis for an air separation unit (ASU) and carbon dioxide (CO{sub 2}) compression design systems. Different plant configurations considered in the study included a flue gas composition exiting system with 95 mol per cent 02 oxidant after drying specified moisture content; a flue gas composition exiting system with 99 mol per cent 02 oxidant; and flue gas purified to meet enhanced oil recovery (EOR) specifications. The results of the air-fired SC and USC boilers compared with amine scrubbing and SC and USC oxy-combustion cases showed an efficiency decrease of 11 and 12 per cent for the SC and USC cases. Oxy-combustion was also the lowest in cost of all CO{sub 2} technologies considered in the project. Results showed that conversion of air blown SC and USC designs for oxy-coal combustion facilitated CO{sub 2} capture, and resulted in net plant efficiency penalties of 11 to 12 per cent. No air emissions were released in cases modelled to meet CO{sub 2} specifications. It was concluded that the 95 per cent mole oxygen treatment is more economical than the 99 per cent mole oxygen system. 3 tabs., 3 figs.

  2. Combustion characterization of beneficiated coal-based fuels. Quarterly report No. 8, January--March 1991

    Energy Technology Data Exchange (ETDEWEB)

    Chow, O.K.; Nsakala, N.Y.

    1991-07-01

    The Pittsburgh Energy Technology Center of the US Department of Energy has contracted with Combustion Engineering, Inc. (CE) to perform a five-year project on ``Combustion Characterization of Beneficiated Coal-Based Fuels.`` The beneficiated coals are produced by other contractors under the DOE Coal Preparation Program. Several contractor-developed advanced coal cleaning processes are run at pilot-scale cleaning facilities to produce 20-ton batches of fuels for shipment to CE`s laboratory in Windsor, Connecticut. CE then processes the products into either a coal-water fuel (CWF) or a dry microfine pulverized coa1 (DMPC) form for combustion testing. The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of BCFs influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. During the third quarter of 1991, the following technical progress was made: Calculated the kinetic characteristics of chars from the combustion of spherical oil agglomeration beneficiated products; continued drop tube devolatilization tests of the spherical oil agglomeration beneficiated products; continued analyses of the data and samples from the CE pilot-scale tests of nine fuels; and started writing a summary topical report to include all results on the nine fuels tested.

  3. Chemical looping combustion of coal in interconnected fluidized beds

    Institute of Scientific and Technical Information of China (English)

    SHEN LaiHong; ZHENG Min; XIAO Jun; ZHANG Hui; XIAO Rui

    2007-01-01

    Chemical looping combustion is the indirect combustion by use of oxygen carrier.It can be used for CO2 capture in power generating processes. In this paper,chemical looping combustion of coal in interconnected fluidized beds with inherent separation of CO2 is proposed. It consists of a high velocity fluidized bed as an air reactor in which oxygen carrier is oxidized, a cyclone, and a bubbling fluidized bed as a fuel reactor in which oxygen carrier is reduced by direct and indirect reactions with coal. The air reactor is connected to the fuel reactor through the cyclone. To raise the high carbon conversion efficiency and separate oxygen carrier particle from ash, coal slurry instead of coal particle is introduced into the bottom of the bubbling fluidized bed. Coal gasification and the reduction of oxygen carrier with the water gas take place simultaneously in the fuel reactor. The flue gas from the fuel reactor is CO2 and water. Almost pure CO2 could be obtained after the condensation of water. The reduced oxygen carrier is then returned back to the air reactor, where it is oxidized with air. Thermodyanmics analysis indicates that NiO/Ni oxygen carrier is the optimal one for chemical looping combustion of coal.Simulation of the processes for chemical looping combustion of coal, including coal gasification and reduction of oxygen carrier, is carried out with Aspen Plus software. The effects of air reactor temperature, fuel reactor temperature, and ratio of water to coal on the composition of fuel gas, recirculation of oxygen carrier particles, etc., are discussed. Some useful results are achieved. The suitable temperature of air reactor should be between 1050-1150Cand the optimal temperature of the fuel reactor be between 900-950℃.

  4. Chemical looping combustion of coal in interconnected fluidized beds

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Chemical looping combustion is the indirect combustion by use of oxygen carrier. It can be used for CO2 capture in power generating processes. In this paper, chemical looping combustion of coal in interconnected fluidized beds with inherent separation of CO2 is proposed. It consists of a high velocity fluidized bed as an air reactor in which oxygen carrier is oxidized, a cyclone, and a bubbling fluidized bed as a fuel reactor in which oxygen carrier is reduced by direct and indirect reactions with coal. The air reactor is connected to the fuel reactor through the cyclone. To raise the high carbon conversion efficiency and separate oxygen carrier particle from ash, coal slurry instead of coal particle is introduced into the bottom of the bubbling fluidized bed. Coal gasification and the reduction of oxygen carrier with the water gas take place simultaneously in the fuel reactor. The flue gas from the fuel reactor is CO2 and water. Almost pure CO2 could be obtained after the con- densation of water. The reduced oxygen carrier is then returned back to the air reactor, where it is oxidized with air. Thermodyanmics analysis indicates that NiO/Ni oxygen carrier is the optimal one for chemical looping combustion of coal. Simulation of the processes for chemical looping combustion of coal, including coal gasification and reduction of oxygen carrier, is carried out with Aspen Plus software. The effects of air reactor temperature, fuel reactor temperature, and ratio of water to coal on the composition of fuel gas, recirculation of oxygen carrier par- ticles, etc., are discussed. Some useful results are achieved. The suitable tem- perature of air reactor should be between 1050―1150℃and the optimal temperature of the fuel reactor be between 900―950℃.

  5. Experimental study on pollution emission from combustion of blended coals

    Energy Technology Data Exchange (ETDEWEB)

    Li Yonghua; Chen Hongwei; Zhen Zhi; Liu Jizhen; Feng Zhaoxing; Dong Jianxun [North China Electric Power University, Baoding (China)

    2003-07-01

    The pollution brought by NOx and SOx produced by coal combustion is getting recognition by each country in the world. This paper adopts an experimental method, selects four kinds of lignite and three kinds of soft coal that are mainly used by some power plant and reports a study of the pollution emission characteristics of component and blended coals. The test rig is introduced from Canada with a capacity of 640 MJ/h with a complete milling system and flue gas online analysis system. The study focuses on the influence of oxygen concentration, pulverized coal fineness and pulverized coal nitrogen content on the pollution emission. The study is useful for achieving clean combustion in large power plants. 5 refs., 4 figs., 7 tabs.

  6. Combustion characterization of beneficiated coal-based fuels. Quarterly report No. 15, October--December 1992

    Energy Technology Data Exchange (ETDEWEB)

    Chow, O.K.; Nsakala, N.Y.

    1993-03-01

    The Pittsburgh Energy Technology Center of the US Department of Energy has contracted with Combustion Engineering, Inc. (CE) to perform a five-year project on ``Combustion Characterization of Beneficiated Coal-Based Fuels.`` The beneficiated coals are produced by other contractors under the DOE Coal Preparation Program. Several contractor-developed advanced coal cleaning processes are run at pilot-scale cleaning facilities to produce 20-ton batches of fuels for shipment to CE`s laboratory in Windsor, Connecticut. CE then processes the products into either a coal-water fuel (CWF) or a dry microfine pulverized coa1 (DMPC) form for combustion testing. The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of BCFs influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. The technical approach used to develop the technical data includes: bench-scale fuel property, combustion, and ash deposition tests; pilot-scale combustion and ash effects tests; and full-scale combustion tests. During the third quarter of 1992, the following technical progress was made: Continued analyses of drop tube furnace samples to determine devolatilization kinetics; re-analyzed the samples from the pilot-scale ash deposition tests of the first nine feed coals and BCFs using a modified CCSEM technique; updated the topical summary report; and prepared for upcoming tests of new BCFs being produced.

  7. Management of high sulfur coal combustion residues, issues and practices: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Chugh, Y.P.; Beasley, G.A. [eds.

    1994-10-01

    Papers presented at the following sessions are included in this proceedings: (1) overview topic; (2) characterization of coal combustion residues; (3) environmental impacts of residues management; (4) materials handling and utilization, Part I; and (5) materials handling and utilization, Part II. Selected paper have been processed separately for inclusion in the Energy Science and Technology Database.

  8. 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.

  9. 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.

  10. Clean coal technology: The new coal era

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    The Clean Coal Technology Program is a government and industry cofunded effort to demonstrate a new generation of innovative coal processes in a series of full-scale showcase`` facilities built across the country. Begun in 1986 and expanded in 1987, the program is expected to finance more than $6.8 billion of projects. Nearly two-thirds of the funding will come from the private sector, well above the 50 percent industry co-funding expected when the program began. The original recommendation for a multi-billion dollar clean coal demonstration program came from the US and Canadian Special Envoys on Acid Rain. In January 1986, Special Envoys Lewis and Davis presented their recommendations. Included was the call for a 5-year, $5-billion program in the US to demonstrate, at commercial scale, innovative clean coal technologies that were beginning to emerge from research programs both in the US and elsewhere in the world. As the Envoys said: if the menu of control options was expanded, and if the new options were significantly cheaper, yet highly efficient, it would be easier to formulate an acid rain control plan that would have broader public appeal.

  11. Mercury in coal and the impact of coal quality on mercury emissions from combustion systems

    Science.gov (United States)

    Kolker, A.; Senior, C.L.; Quick, J.C.

    2006-01-01

    The proportion of Hg in coal feedstock that is emitted by stack gases of utility power stations is a complex function of coal chemistry and properties, combustion conditions, and the positioning and type of air pollution control devices employed. Mercury in bituminous coal is found primarily within Fe-sulfides, whereas lower rank coal tends to have a greater proportion of organic-bound Hg. Preparation of bituminous coal to reduce S generally reduces input Hg relative to in-ground concentrations, but the amount of this reduction varies according to the fraction of Hg in sulfides and the efficiency of sulfide removal. The mode of occurrence of Hg in coal does not directly affect the speciation of Hg in the combustion flue gas. However, other constituents in the coal, notably Cl and S, and the combustion characteristics of the coal, influence the species of Hg that are formed in the flue gas and enter air pollution control devices. The formation of gaseous oxidized Hg or particulate-bound Hg occurs post-combustion; these forms of Hg can be in part captured in the air pollution control devices that exist on coal-fired boilers, without modification. For a given coal type, the capture efficiency of Hg by pollution control systems varies according to type of device and the conditions of its deployment. For bituminous coal, on average, more than 60% of Hg in flue gas is captured by fabric filter (FF) and flue-gas desulfurization (FGD) systems. Key variables affecting performance for Hg control include Cl and S content of the coal, the positioning (hot side vs. cold side) of the system, and the amount of unburned C in coal ash. Knowledge of coal quality parameters and their effect on the performance of air pollution control devices allows optimization of Hg capture co-benefit. ?? 2006 Elsevier Ltd. All rights reserved.

  12. [Inventories of atmospheric arsenic emissions from coal combustion in China, 2005].

    Science.gov (United States)

    Tian, He-Zhong; Qu, Yi-Ping

    2009-04-15

    Anthropogenic arsenic (As) emitted from coal combustion is one of key trace elements leading to negative air pollution and national economy loss. It is of great significance to estimate the atmospheric arsenic emission for proposing relevant laws or regulations and selecting proper pollution control technologies. The inventories of atmospheric arsenic emissions from coal combustion in China were evaluated by adopting the emission factor method based on fuel consumption. Arsenic emission sources were firstly classified into several categories by economic sectors, combustion types and pollution control technologies. Then, according to provincial coal consumption and averaged arsenic concentration in the feed fuel, the inventories of atmospheric arsenic emission from coal combustion in China in 2005 were established. Coal outputand consumption in China in 2005 were 2,119.8 and 2,099.8 Mt, respectively. The total emissions of arsenic released into the atmosphere in 2005 in China were estimated at about 1,564.4 t, and Shandong ranked the largest province with 144.4 t arsenic release, followed by Hunan (141.1 t), Hebei (108.5 t), Henan (77.7 t), and Jiangsu (77.0 t), which were mainly concentrated in the eastern and central provinces of China. The arsenic emissions were largely emitted by industry sector (818.8 t) and thermal power generation sector (303.4 t), contributing 52.3% and 19.4% of the totals, respectively. About 375.5 t arsenic was estimated to be released into the atmosphere in the form of gas phase in China in 2005, with a share of 24% of the totals. In general, arsenic pollution control from coal combustion should be highlighted for the power and industry sectors in the whole country. However, arsenic poisoning caused by residential coal burning should also be paid great attention in some areas such as Xinjiang, Gansu, Qinghai and Guishou.

  13. Chemical analyses of coal, coal-associated rocks and coal combustion products collected for the National Coal Quality Inventory

    Science.gov (United States)

    Hatch, Joseph R.; Bullock, John H.; Finkelman, Robert B.

    2006-01-01

    In 1999, the USGS initiated the National Coal Quality Inventory (NaCQI) project to address a need for quality information on coals that will be mined during the next 20-30 years. At the time this project was initiated, the publicly available USGS coal quality data was based on samples primarily collected and analyzed between 1973 and 1985. The primary objective of NaCQI was to create a database containing comprehensive, accurate and accessible chemical information on the quality of mined and prepared United States coals and their combustion byproducts. This objective was to be accomplished through maintaining the existing publicly available coal quality database, expanding the database through the acquisition of new samples from priority areas, and analysis of the samples using updated coal analytical chemistry procedures. Priorities for sampling include those areas where future sources of compliance coal are federally owned. This project was a cooperative effort between the U.S. Geological Survey (USGS), State geological surveys, universities, coal burning utilities, and the coal mining industry. Funding support came from the Electric Power Research Institute (EPRI) and the U.S. Department of Energy (DOE).

  14. The release of iron during coal combustion. Milestone report

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, L.L. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility

    1995-06-01

    Iron plays an important role in the formation of both fly ash and deposits in many pulverized-coal-fired boilers. Several authors indicate that iron content is a significant indicator of the slagging propensity of a majority of US bituminous coals, in particular eastern bituminous coals. The pyritic iron content of these coals is shown to be a particularly relevant consideration. A series of investigations of iron release during combustion is reported for a suite of coals ranging in rank from lignite to low-volatile bituminous coal under combustion conditions ranging from oxidizing to inert. Experimental measurements are described in which, under selected conditions, major fractions of the iron in the coal are released within a 25 ms period immediately following coal devolatilization. Mechanistic interpretation of the data suggest that the iron is released as a consequence of oxygen attack on porous pyrrhotite particles. Experimental testing of the proposed mechanism reveals that the release is dependent on the presence of both pyrite in the raw coal and oxygen in the gas phase, that slow preoxidation (weathering) of the pyrite significantly inhibits the iron release, and that iron loss increases as oxygen penetration of the particle increases. Each observation is consistent with the postulated mechanism.

  15. Survey of environmental-control technologies for industrial coal use

    Energy Technology Data Exchange (ETDEWEB)

    Seward, W.H.; Hollis, J.R.; Opalanko, R.S.

    1978-12-01

    This report presents the results of a screening study done by Mittelhauser Corporation for Argonne National Laboratory. The purpose of the study is to examine current and possible future constraints on the use of coal and coal-derived fuels in industry. Current environmental regulations pertaining to industrial fuel usage are listed and summarized. A Technology-Applications Matrix (TAM), which correlates generic types of industrial fuel-burning equipment with potential fuels, is a key element in this report. The study has led to several conclusions. Current environmental constraints may reduce significantly the attractiveness of coal-derived solid fuels. Coal-derived medium-Btu gases and methanol are unlikely to be economically competitive with natural gas, fuel oil, or other coal-derived synthetic fuels by 1985. It is unlikely that National Energy Act provisions, which force conversion of industrial facilities to coal-use, will be effective in changing the industrial fuel-use pattern in the United States in the near future. The most attractive application of coal technology in the industrial sector appears to be direct use of high-sulfur coal with post-combustion pollution control. It is recommended that this alternative be examined, along with the use of atmospheric fluidized-bed combustion, coal-oil mixtures, solvent-refined coal liquids, and high-Btu synthetic gas.

  16. Toxic substances from coal combustion -- A comprehensive assessment

    Energy Technology Data Exchange (ETDEWEB)

    C.L. Senior; T. Panagiotou; F.E. Huggins; G.P. Huffman; N. Yap; J.O.L. Wendt; W. Seames; M.R. Ames; A.F Sarofim; J. Lighty; A. Kolker; R. Finkelman; C.A. Palmer; S.J. Mroczkowsky; J.J. Helble; R. Mamani-Paco

    1999-11-01

    The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPs) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the Federal Energy Technology Center (FETC), the Electric Power Research Institute, and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (UU) and the University of North Dakota Energy and Environmental Research Center (EERC) to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NOx combustion systems, and new power generation plants. Development of ToPEM will be based on PSI's existing Engineering Model for Ash Formation (EMAF). This report covers the reporting period from 1 July 1999 to 30 September 1999. During this period the MIT INAA procedures were revised to improve the quality of the analytical results. Two steps have been taken to reduce the analytical errors. A new nitric acid leaching procedure, modified from ASTM procedure D2492, section 7.3.1 for determination of pyritic sulfur, was developed by USGS and validated. To date, analytical results have been returned for all but the last complete round of the four-step leaching procedure. USGS analysts in Denver have halted development of the cold vapor atomic fluorescence technique for mercury analysis procedure in favor of a new direct analyzer for Hg that the USGS is in the process of acquiring. Since early June, emphasis at USGS has been placed on microanalysis of clay minerals in project coals in

  17. Appalachian clean coal technology consortium

    Energy Technology Data Exchange (ETDEWEB)

    Kutz, K.; Yoon, Roe-Hoan [Virginia Polytechnic Institute and State Univ., Blacksburg, VA (United States)

    1995-11-01

    The Appalachian Clean Coal Technology Consortium (ACCTC) has been established to help U.S. coal producers, particularly those in the Appalachian region, increase the production of lower-sulfur coal. The cooperative research conducted as part of the consortium activities will help utilities meet the emissions standards established by the 1990 Clean Air Act Amendments, enhance the competitiveness of U.S. coals in the world market, create jobs in economically-depressed coal producing regions, and reduce U.S. dependence on foreign energy supplies. The research activities will be conducted in cooperation with coal companies, equipment manufacturers, and A&E firms working in the Appalachian coal fields. This approach is consistent with President Clinton`s initiative in establishing Regional Technology Alliances to meet regional needs through technology development in cooperation with industry. The consortium activities are complementary to the High-Efficiency Preparation program of the Pittsburgh Energy Technology Center, but are broader in scope as they are inclusive of technology developments for both near-term and long-term applications, technology transfer, and training a highly-skilled work force.

  18. Control of mercury emissions from stationary coal combustion sources in China: Current status and recommendations.

    Science.gov (United States)

    Hu, Yuanan; Cheng, Hefa

    2016-11-01

    Coal burning in power plants and industrial boilers is the largest combustion source of mercury emissions in China. Together, power plants and industrial boilers emit around 250 tonnes of mercury each year, or around half of atmospheric mercury emissions from anthropogenic sources in the country. Power plants in China are generally equipped with multi-pollutant control technologies, which offer the co-benefit of mercury removal, while mercury-specific control technologies have been installed in some facilities. In contrast, most industrial boilers have only basic or no flue gas cleaning. A combination of measures, including energy conservation, coal switching and blending, reducing the mercury contents of coals through washing, combustion controls, and flue gas cleaning, can be used to reduce mercury emissions from these stationary combustion sources. More stringent emission standards for the major air pollutants from coal-fired power plants and industrial boiler, along with standards for the previously unregulated mercury, were implemented recently, which is expected to bring significant reduction in their mercury emissions through the necessary upgrades of multi-pollutant and mercury-specific control technologies. Meanwhile, strong monitoring capacity and strict enforcement are necessary to ensure that the combustion sources operate in compliance with the new emission standards and achieve significant reduction in the emissions of mercury and other air pollutants.

  19. (Pittsburgh Energy Technology Center): Quarterly technical progress report for the period ending June 30, 1987. [Advanced Coal Research and Technology Development Programs

    Energy Technology Data Exchange (ETDEWEB)

    None

    1988-02-01

    Research programs on coal and coal liquefaction are presented. Topics discussed are: coal science, combustion, kinetics, surface science; advanced technology projects in liquefaction; two stage liquefaction and direct liquefaction; catalysts of liquefaction; Fischer-Tropsch synthesis and thermodynamics; alternative fuels utilization; coal preparation; biodegradation; advanced combustion technology; flue gas cleanup; environmental coordination, and technology transfer. Individual projects are processed separately for the data base. (CBS)

  20. Pyrolysis and combustion behaviour of coal-MBM blends.

    Science.gov (United States)

    Skodras, G; Grammelis, P; Basinas, P

    2007-01-01

    In the present work, thermogravimetric analysis was employed in order to investigate the behaviour of MBM and their blends with Greek brown coal, under pyrolysis and combustion conditions. MBM presented enhanced pyrolysis rates reflecting its high volatile and low ash contents compared to Greek brown coal. Increased conversion rates were observed when MBM was added in the brown coal sample. Significant interactions were detected between the two fuel blend components leading to significant deviations from the expected behaviour. The catalytic effect of mineral matter on the pyrolysis of MBM resulted in reaction rate decrease and DTG curve shift to lower temperatures for the demineralised MBM. Alterations in the combustion process due to the mineral matter were minimal when testing the blends. Interactions maintained during combustion and lower reactivity of MBM was achieved due to the reduced oxygen content.

  1. Pyrolysis and combustion behaviour of coal-MBM blends

    Energy Technology Data Exchange (ETDEWEB)

    Skodras, G.; Grammelis, P.; Basinas, P. [Center for Research & Technology Hellas, Ptolemais (Greece)

    2007-01-15

    In the present work, thermogravimetric analysis was employed in order to investigate the behaviour of MBM (meat and bone meal) and their blends with Greek brown coal, under pyrolysis and combustion conditions. MBM presented enhanced pyrolysis rates reflecting its high volatile and low ash contents compared to Greek brown coal. Increased conversion rates were observed when MBM was added in the brown coal sample. Significant interactions were detected between the two fuel blend components leading to significant deviations from the expected behaviour. The catalytic effect of mineral matter on the pyrolysis of MBM resulted in reaction rate decrease and DTG curve shift to lower temperatures for the demineralised MBM. Alterations in the combustion process due to the mineral matter were minimal when testing the blends. Interactions maintained during combustion and lower reactivity of MBM was achieved due to the reduced oxygen content.

  2. JV Task 108 - Circulating Fluidized-Bed Combustion and Combustion Testing of Turkish Tufanbeyli Coal

    Energy Technology Data Exchange (ETDEWEB)

    Douglas Hajicek; Jay Gunderson; Ann Henderson; Stephen Sollom; Joshua Stanislowski

    2007-08-15

    Two combustion tests were performed at the Energy & Environmental Research Center (EERC) using Tufanbeyli coal from Turkey. The tests were performed in a circulating fluidized-bed combustor (CFBC) and a pulverized coal-fired furnace, referred to as the combustion test facility (CTF). One of the goals of the project was to determine the type of furnace best suited to this coal. The coal is high in moisture, ash, and sulfur and has a low heating value. Both the moisture and the sulfur proved problematic for the CTF tests. The fuel had to be dried to less than 37% moisture before it could be pulverized and further dried to about 25% moisture to allow more uniform feeding into the combustor. During some tests, water was injected into the furnace to simulate the level of flue gas moisture had the fuel been fed without drying. A spray dryer was used downstream of the baghouse to remove sufficient sulfur to meet the EERC emission standards permitted by the North Dakota Department of Health. In addition to a test matrix varying excess air, burner swirl, and load, two longer-term tests were performed to evaluate the fouling potential of the coal at two different temperatures. At the lower temperature (1051 C), very little ash was deposited on the probes, but deposition did occur on the walls upstream of the probe bank, forcing an early end to the test after 2 hours and 40 minutes of testing. At the higher temperature (1116 C), ash deposition on the probes was significant, resulting in termination of the test after only 40 minutes. The same coal was burned in the CFBC, but because the CFBC uses a larger size of material, it was able to feed this coal at a higher moisture content (average of 40.1%) compared to the CTF (ranging from 24.2% to 26.9%). Sulfur control was achieved with the addition of limestone to the bed, although the high calcium-to-sulfur rate required to reduce SO{sub 2} emissions resulted in heat loss (through limestone calcination) and additional ash

  3. USGS TOXIC SUBSTANCES FROM COAL COMBUSTION -- FORMS OF OCCURRENCE ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    Allan Kolker; Stanley J. Mroczkowski; Curtis A. Palmer; Robert B. Finkelman

    1999-04-01

    Detailed information on trace-element modes of occurrence in coal is essential to understanding and predicting trace-element transformations taking place during coal combustion. The USGS has developed quantitative and semi-quantitative methods for determining the mode of occurrence of trace elements in coal. This information is needed to generate predictive models for trace-element behavior, the ultimate goal of DOE contract DE-AC22-95PC95101 ``Toxic Substances From Coal Combustion--A Comprehensive Assessment'' awarded to PSI, Inc. USGS activities in support of this contract have a direct bearing on the predictive equations being developed as the primary product of the PSI program.

  4. Combustion tests of coal-water slurry. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Farthing, G.A. Jr.; Johnson, S.A.; Vecci, S.J.

    1982-03-01

    The results of an experimental test program to determine the combustion characteristics of coal-water slurry (CWS) fuels (65 to 75 percent dry coal by weight and exhibiting room temperature viscosities of about 1000 cp) are presented. The slurry tested contained 66 percent solids by weight and was produced from a beneficiated high volatile eastern bituminous coal. The CWS and its parent coal were each fired in B and W's 4.0 x 10/sup 6/ Btu/hr Basic Combustion Test Unit. Each fuel was also subjected to extensive laboratory analysis work. No burner or atomizer development work was done - the primary objective of the study being to demonstrate that the CWS could be fired with existing fuel oil handling equipment.

  5. Combustion of coal gas fuels in a staged combustor

    Science.gov (United States)

    Rosfjord, T. J.; Mcvey, J. B.; Sederquist, R. A.; Schultz, D. F.

    1982-01-01

    Gaseous fuels produced from coal resources generally have heating values much lower than natural gas; the low heating value could result in unstable or inefficient combustion. Coal gas fuels may contain ammonia which if oxidized in an uncontrolled manner could result in unacceptable nitrogen oxide exhaust emission levels. Previous investigations indicate that staged, rich-lean combustion represents a desirable approach to achieve stable, efficient, low nitrogen oxide emission operation for coal-derived liquid fuels contaning up to 0.8-wt pct nitrogen. An experimental program was conducted to determine whether this fuel tolerance can be extended to include coal-derived gaseous fuels. The results of tests with three nitrogen-free fuels having heating values of 100, 250, and 350 Btu/scf and a 250 Btu/scf heating value doped to contain 0.7 pct ammonia are presented.

  6. Influence of Process Parameters on Coal Combustion Performance

    DEFF Research Database (Denmark)

    Lans, Robert Pieter Van Der

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

  7. OxyFuel combustion of Coal and Biomass

    DEFF Research Database (Denmark)

    Toftegaard, Maja Bøg

    of coal and straw at conditions relevant to suspension-fired boilers by clarifying the effect of the change in combustion atmosphere on fuel burnout, flame temperatures, emissions of polluting species (NO, SO2, and CO), fly ash quality, and deposit formation. This work is one of the first to investigate...... and oxyfuel atmospheres. Apart from slightly improved burnout and reduced emissions of NO during oxyfuel combustion these operating conditions yield similar combustion characteristics in both environments. Co-firing coal and biomass or combustion of pure biomass in an oxyfuel power plant could yield...... be adjusted independently. By increasing the concentration of oxygen in the oxidant, i.e. by reducing the flue gas recirculation ratio, it is possible to achieve similar burnout at lower oxygen excess levels. Further work on implications of this strategy are necessary in order to fully clarify its potential...

  8. Temperature Trends in Coal Char Combustion under Oxy-fuel Conditions for the Determination of Kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, Samira [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hecht, Ethan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-08-01

    Oxy-fuel combustion technology with carbon capture and storage could significantly reduce global CO2 emissions, a greenhouse gas. Implementation can be aided by computational fluid dynamics (CFD) simulations, which require an accurate understanding of coal particle kinetics as they go through combustion in a range of environments. To understand the kinetics of pulverized coal char combustion, a heated flow reactor was operated under a wide range of experimental conditions. We varied the environment for combustion by modifying the diluent gas, oxygen concentration, gas flow rate, and temperature of the reactor/reacting gases. Measurements of reacting particle temperatures were made for a sub-bituminous and bituminous coal char, in environments with CO2 or N2 as the diluent gas, with 12, 24, and 36 vol-% oxygen concentration, at 50, 80, 100, and 200 standard liters per minute flowing through the reactor, reactor temperatures of 1200, 1400 K, at pressures slightly above atmospheric. The data shows consistent increasing particle temperature with increased oxygen concentration, reactor temperature and higher particle temperatures for N2 diluent than CO2. We also see the effects of CO2 gasification when different ranks of coal are used, and how the reduction in the temperature due to the CO2 diluent is greater for the coal char that has higher reactivity. Quantitative measurements for temperature are not yet complete due to ongoing calibration of detection systems.

  9. A new theory of chemical method to prevent spontaneous combustion of coal

    Institute of Scientific and Technical Information of China (English)

    LU Wei

    2009-01-01

    In order to prevent spontaneous combustion of coal from the source, based on the study on the mechanism of spontaneous combustion of coal, especially the process of coal to self-ignite and different activate structures have different activation for oxidization, the new theory and mechanism with chemical inhibition that can change the tendency of spontaneous combustion of coal and let the activate structures deactivate were brought forward. Therefore, coal was not self-ignited under a certain temperature when being chemically inhibited.

  10. Development and testing of commercial-scale, coal-fired combustion systems, Phase 3

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    The US Department of Energy's Pittsburgh Energy Technology Center (PETC) is actively pursuing the development and testing of coal-fired combustion systems for residential, commercial, and industrial market sectors. In response, MTCI initiated the development of a new combustor technology based on the principle of pulse combustion under the sponsorship of PETC (Contract No. AC22-83PC60419). The initial pulse combustor development program was conducted in three phases (MTCI, Development of a Pulsed Coal Combustor Fired with CWM, Phase III Final Report, DOE Contract No. AC22-83PC60419, November 1986). Phase I included a review of the prior art in the area of pulse combustion and the development of pulse combustor design concepts. It led to the conclusion that pulse combustors offer technical and base-of-operation advantages over conventional burners and also indicated favorable economics for replacement of oil- and gas-fired equipment.

  11. Enrichment of trace elements in bottom ash from coal oxy-combustion: Effect of coal types

    CSIR Research Space (South Africa)

    Oboirien, BO

    2016-09-01

    Full Text Available In this study, the enrichment of trace elements in two coals under air and oxy-combustion conditions was studied. Twenty-one trace elements were evaluated. The two coal samples had a different concentration for the 21 trace elements, which was due...

  12. Clean Coal Technology Demonstration Program. Program update 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    The Clean Coal Technology Demonstration Program (CCT Program) is a $7.14 billion cost-shared industry/government technology development effort. The program is to demonstrate a new generation of advanced coal-based technologies, with the most promising technologies being moved into the domestic and international marketplace. Clean coal technologies being demonstrated under the CCT program are creating the technology base that allows the nation to meet its energy and environmental goals efficiently and reliably. The fact that most of the demonstrations are being conducted at commercial scale, in actual user environments, and under conditions typical of commercial operations allows the potential of the technologies to be evaluated in their intended commercial applications. The technologies are categorized into four market sectors: advanced electric power generation systems; environmental control devices; coal processing equipment for clean fuels; and industrial technologies. Sections of this report describe the following: Role of the Program; Program implementation; Funding and costs; The road to commercial realization; Results from completed projects; Results and accomplishments from ongoing projects; and Project fact sheets. Projects include fluidized-bed combustion, integrated gasification combined-cycle power plants, advanced combustion and heat engines, nitrogen oxide control technologies, sulfur dioxide control technologies, combined SO{sub 2} and NO{sub x} technologies, coal preparation techniques, mild gasification, and indirect liquefaction. Industrial applications include injection systems for blast furnaces, coke oven gas cleaning systems, power generation from coal/ore reduction, a cyclone combustor with S, N, and ash control, cement kiln flue gas scrubber, and pulse combustion for steam coal gasification.

  13. Numerical study of bituminous coal combustion in a boiler furnace with bottom blowing

    Science.gov (United States)

    Zroychikov, N. A.; Kaverin, A. A.

    2016-11-01

    Results obtained by the numerical study of a solid fuel combustion scheme with bottom blowing using Ekibastuz and Kuznetsk bituminous coals of different fractional makeup are presented. Furnace chambers with bottom blowing provide high-efficiency combustion of coarse-grain coals with low emissions of nitrogen oxides. Studying such a combustion scheme, identification of its technological capabilities, and its further improvement are topical issues. As the initial object of study, we selected P-57-R boiler plant designed for burning of Ekibastuz bituminous coal in a prismatic furnace with dry-ash (solid slag) removal. The proposed modernization of the furnace involves a staged air inflow under the staggered arrangement of directflow burners (angled down) and bottom blowing. The calculation results revealed the specific aerodynamics of the flue gases, the trajectories of solid particles in the furnace chamber, and the peculiarities of the fuel combustion depending on the grinding fineness. It is shown that, for coal grinding on the mill, the overall residue on the screen plate of 90 µm ( R 90 ≤ 27% for Ekibastuz coal and R 90 ≤ 15% for Kuznetsk coal) represents admissible values for fuel grind coarsening in terms of economic efficiency and functional reliability of a boiler. The increase in these values leads to the excess of regulatory heat losses and unburned combustible losses. It has been established that the change in the grade of the burned coal does not significantly affect the flow pattern of the flue gases, and the particles trajectory is essentially determined by the elemental composition of the fuel.

  14. Low-rank coal research: Volume 3, Combustion research: Final report. [Great Plains

    Energy Technology Data Exchange (ETDEWEB)

    Mann, M. D.; Hajicek, D. R.; Zobeck, B. J.; Kalmanovitch, D. P.; Potas, T. A.; Maas, D. J.; Malterer, T. J.; DeWall, R. A.; Miller, B. G.; Johnson, M. D.

    1987-04-01

    Volume III, Combustion Research, contains articles on fluidized bed combustion, advanced processes for low-rank coal slurry production, low-rank coal slurry combustion, heat engine utilization of low-rank coals, and Great Plains Gasification Plant. These articles have been entered individually into EDB and ERA. (LTN)

  15. A kinetic model of carbon burnout in pulverized coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Hurt, R.; Jian-Kuan Sun; Lunden, M. [Brown University, Providence, RI (United States). Division of Engineering

    1998-04-01

    The degree of carbon burnout is an important operating characteristic of full-scale suspension-fired coal combustion systems affecting boiler efficiency, electrostatic precipitator operation and the value of fly ash as a saleable product. Prediction of carbon loss requires special char combustion kinetics valid through the very high conversions targeted in industry (typically {gt} 99.5%), and valid for a wide-range of particle temperature histories occurring in full-scale furnaces. The paper presents high-temperature kinetic data for five coal chars in the form of time-resolved burning profiles that include the late stages of combustion. It then describes the development and validation of the Carbon Burnout Kinetic Model (CBK), a coal-general kinetics package that is specifically designed to predict the total extent of carbon burnout and ultimate fly ash carbon content for prescribed temperature/oxygen histories typical of pulverized coal combustion systems. The model combines the single-film treatment of cha oxidation with quantitative descriptions of thermal annealing, statistical kinetics, statistical densities, and ash inhibition in the late stages of combustion. In agreement with experimental observations, the CBK model predicts (1) low reactivities for unburned carbon residues extracted from commercial ash samples, (2) reactivity loss in the late stages of laboratory combustion, (3) the observed sensitivity of char reactivity to high-temperature heat treatment on second and subsecond time scales, and (4) the global reaction inhibition by mineral matter in the late stages of combustion observed in single-particle imaging studies. The model ascribes these various char deactivation phenomena to the combined effects of thermal annealing, ash inhibition, and the preferential consumption of more reactive particles (statistical kinetics), the relative contributions of which vary greatly with combustion conditions. 39 refs., 4 figs., 4 tabs., 1 app.

  16. Comparative Study of Coal and Biomass Co-Combustion With Coal Burning Separately Through Emissions Analysis

    Directory of Open Access Journals (Sweden)

    Mohammad Siddique

    2016-06-01

    Full Text Available Appropriate eco-friendly methods to mitigate the problem of emissions from combustion of fossil fuel are highly demanded. The current study was focused on the effect of using coal & coal-biomass co-combustion on the gaseous emissions. Different biomass' were used along with coal. The coal used was lignite coal and the biomass' were tree waste, cow dung and banana tree leaves. Various ratios of coal and biomass were used to investigate the combustion behavior of coal-biomass blends and their emissions. The study revealed that the ratio of 80:20 of coal (lignite-cow dung and 100% banana tree leaves emits less emissions of CO, CO2, NOx and SO2 as compared to 100% coal. Maximum amount of CO emissions were 1510.5 ppm for banana tree waste and minimum amount obtained for lakhra coal and cow dung manure (70:30 of 684.667 ppm. Maximum percentage of SO2 (345.33 ppm was released from blend of lakhra coal and tree leaves (90:10 and minimum amount of SO2 present in samples is in lakhra coal-banana tree waste (80:20. The maximum amount of NO obtained for banana tree waste were 68 ppm whereas maximum amount of NOx was liberated from lakhra coal-tree leaves (60:40 and minimum amount from cow dung manure (30.83 ppm. The study concludes that utilization of biomass with coal could make remedial action against environment pollution.

  17. MECHANISMS AND OPTIMIZATION OF COAL COMBUSTION

    Energy Technology Data Exchange (ETDEWEB)

    Kyriacos Zygourakis

    1998-05-01

    We report the development of a novel experimental technique that combines video microscopy and thermogravimetric analysis to optimize the detection of coal and char particle ignitions. This technique is particularly effective for detecting ignitions occurring in coal or char samples containing multiple particles, where other commonly used techniques fail. The new approach also allows for visualization of ignition mechanism. Devolatilized char particles appear to ignite heterogeneously, while coal particles may ignite homogeneously, heterogeneously or through a combination of both mechanisms.

  18. Detection of Coal Mine Spontaneous Combustion by Fuzzy Inference System

    Institute of Scientific and Technical Information of China (English)

    SUN Ji-ping; SONG Shu; MA Feng-ying; ZHANG Ya-li

    2006-01-01

    The spontaneous combustion is a smoldering process and characterized by a slow burning speed and a long duration. Therefore, it is a hazard to coal mines. Early detection of coal mine spontaneous combustion is quite difficult because of the complexity of different coal mines. And the traditional threshold discriminance is not suitable for spontaneous combustion detection due to the uncertainty of coalmine combustion. Restrictions of the single detection method will also affect the detection precision in the early time of spontaneous combustion. Although multiple detection methods can be adopted as a complementarity to improve the accuracy of detection, the synthesized method will increase the complicacy of criterion, making it difficult to estimate the combustion. To solve this problem, a fuzzy inference system based on CRI (Compositional Rule of Inference) and fuzzy reasoning method FITA (First Infer Then Aggregate) are presented. And the neural network is also developed to realize the fuzzy inference system. Finally, the effectiveness of the inference system is demonstrated by means of an experiment.

  19. Experimental research of sewage sludge with coal and biomass co-combustion, in pellet form.

    Science.gov (United States)

    Kijo-Kleczkowska, Agnieszka; Środa, Katarzyna; Kosowska-Golachowska, Monika; Musiał, Tomasz; Wolski, Krzysztof

    2016-07-01

    Increased sewage sludge production and disposal, as well as the properties of sewage sludge, are currently affecting the environment, which has resulted in legislation changes in Poland. Based on the Economy Minister Regulation of 16 July 2015 (Regulation of the Economy Minister, 2015) regarding the criteria and procedures for releasing wastes for landfilling, the thermal disposal of sewage sludge is important due to its gross calorific value, which is greater than 6MJ/kg, and the problems that result from its use and application. Consequently, increasingly restrictive legislation that began on 1 January 2016 was introduced for sewage sludge storage in Poland. Sewage sludge thermal utilisation is an attractive option because it minimizes odours, significantly reduces the volume of starting material and thermally destroys the organic and toxic components of the off pads. Additionally, it is possible that the ash produced could be used in different ways. Currently, as many as 11 plants use sewage sludge as fuel in Poland; thus, this technology must be further developed in Poland while considering the benefits of co-combustion with other fuels. This paper presents the results of experimental studies of the mechanisms and kinetics of sewage sludge, coal and biomass combustion and their co-combustion in spherical-pellet form. Compared with biomass, a higher temperature is required to ignite sewage sludge by flame. The properties of biomass and sewage sludge result in the intensification of the combustion process (by fast ignition of volatile matter). In contrast to coal, a combustion of sewage sludge is determined not only burning the char, but also the combustion of volatiles. The addition of sewage sludge to hard coal and lignite shortens combustion times compared with coal, and the addition of sewage sludge to willow Salix viminalis produces an increase in combustion time compared with willow alone. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2014-12-01

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

  1. Progress in Coal Liquefaction Technologies

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Worldwide primary energy consumption is entering an era of pluralism and high quality under the influence of rapid economic development, increasing energy shortage and strict environmental policies. Although renewable energy technology is developing rapidly, fossil fuels (coal, oil and gas) are still the dominant energy sources in the world. As a country rich in coal but short ofoil and gas, China's oil imports have soared in the past few years. Government, research organizations and enterprises in China are paying more and more attention to the processes of converting coal into clean liquid fuels. Direct and indirect coal liquefaction technologies are compared in this paper based on China's current energy status and technological progress not only in China itself but also in the world.

  2. NITRIC OXIDE FORMATION DURING PULVERIZED COAL COMBUSTION

    Science.gov (United States)

    Data on the overall conversion of coal-nitrogen to NOx were obtained at 1250 K and 1750 K for a residence time of one second. The conversion of coal-nitrogen to NOx decreased monotonically with increasing fuel/oxygen equivalence ratio and decreased slightly with increasing temper...

  3. Ash formation under pressurized pulverized coal combustion conditions

    Science.gov (United States)

    Davila Latorre, Aura Cecilia

    Coal combustion is a source of inorganic particulate matter (ash), which can deposit in boilers and also be emitted into the atmosphere becoming part of ambient fine particulate matter (PM 2.5). In order to decrease coal combustion emissions per unit of power produced, higher efficiency systems have been proposed, including systems operating at elevated pressures. These new operating conditions will affect pollutant formation mechanisms, particularly those associated with the conversion of mineral matter to ash. Ash particle formation mechanisms are particularly sensitive to changes in pressure as they are related to the structure of coal char particles at early stages of combustion. To assess the importance of pressure on ash particle formation, pyrolyzed chars and ash particles from pressurized pulverized combustion of two bituminous and one subbituminous U.S. coals at operating pressures up to 30 atm were studied. Pressure changes the distribution of char particle types, changing the spatial distribution of the minerals during the combustion process and therefore affecting particle formation mechanisms. Chars were examined by Scanning Electron Microscopy (SEM) and classified into two different types (cenospheric and solid) depending on porosity and wall thickness. A correlation for estimating the amount of these cenospheric char particles was then proposed for bituminous coals based on the operating conditions and coal maceral analysis. The ash particle size distribution of the coals combusted at different operating pressures was measured using Computer Controlled Scanning Electron Microscopy (CCSEM). The results of the char characterization and ash particle size distribution measurements were then incorporated into an ash particle formation algorithm that was proposed and implemented. The model predicts ash particle size and composition distributions at elevated pressures under conditions of complete char burnout. Ash predictions were calculated by first

  4. Critical Value of CO of Forecasting Coal Spontaneous Combustion

    Institute of Scientific and Technical Information of China (English)

    HE Qi-ling; DAI Guang-long; WANG De-ming

    2003-01-01

    CO has been used widely in the production process of colliery as an index gas to predict spontaneous combustion of coal. But in some collieries there are CO gas in the upper corner of the face all the times, sometime CO gas even exceeds the regulated critical index. This phenomenon is much more obvious in the fully-mechanized longwall face and fully-mechanized longwall and top-coal caving face. Although many measures of fire-proof and fire-extinguishing have been adopted, the flowing amount of CO gas can be only decreasd, but can not be eliminated completely. Using the different kinds of coal, the experiment of coal oxidation was made at the low temperature. The experiment indicates that some kinds of coal can produce CO under the condition of normal temperature oxidation, sometime the CO consistency is very high, and the intension of CO can be decreased with oxidation time prolonging. Selecting rational critical value of CO is the kev to predicting spontaneous combustion of coal correctly and reliably. The problem of selecting retional critical value of CO was studied. Finally, the amount of CO gas released by different kinds of coal was obtained under normal temperature condition.

  5. Oxidation of Mercury in Products of Coal Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Peter Walsh; Giang Tong; Neeles Bhopatkar; Thomas Gale; George Blankenship; Conrad Ingram; Selasi Blavo Tesfamariam Mehreteab; Victor Banjoko; Yohannes Ghirmazion; Heng Ban; April Sibley

    2009-09-14

    Laboratory measurements of mercury oxidation during selective catalytic reduction (SCR) of nitric oxide, simulation of pilot-scale measurements of mercury oxidation and adsorption by unburned carbon and fly ash, and synthesis of new materials for simultaneous oxidation and adsorption of mercury, were performed in support of the development of technology for control of mercury emissions from coal-fired boilers and furnaces. Conversion of gas-phase mercury from the elemental state to water-soluble oxidized form (HgCl{sub 2}) enables removal of mercury during wet flue gas desulfurization. The increase in mercury oxidation in a monolithic V{sub 2}O{sub 5}-WO{sub 3}/TiO{sub 2} SCR catalyst with increasing HCl at low levels of HCl (< 10 ppmv) and decrease in mercury oxidation with increasing NH{sub 3}/NO ratio during SCR were consistent with results of previous work by others. The most significant finding of the present work was the inhibition of mercury oxidation in the presence of CO during SCR of NO at low levels of HCl. In the presence of 2 ppmv HCl, expected in combustion products from some Powder River Basin coals, an increase in CO from 0 to 50 ppmv reduced the extent of mercury oxidation from 24 {+-} 3 to 1 {+-} 4%. Further increase in CO to 100 ppmv completely suppressed mercury oxidation. In the presence of 11-12 ppmv HCl, increasing CO from 0 to {approx}120 ppmv reduced mercury oxidation from {approx}70% to 50%. Conversion of SO{sub 2} to sulfate also decreased with increasing NH{sub 3}/NO ratio, but the effects of HCl and CO in flue gas on SO{sub 2} oxidation were unclear. Oxidation and adsorption of mercury by unburned carbon and fly ash enables mercury removal in a particulate control device. A chemical kinetic mechanism consisting of nine homogeneous and heterogeneous reactions for mercury oxidation and removal was developed to interpret pilot-scale measurements of mercury oxidation and adsorption by unburned carbon and fly ash in experiments at pilot

  6. Combustion characteristics and arsenic retention during co-combustion of agricultural biomass and bituminous coal.

    Science.gov (United States)

    Zhou, Chuncai; Liu, Guijian; Wang, Xudong; Qi, Cuicui; Hu, Yunhu

    2016-08-01

    A combination of thermogravimetric analysis (TG) and laboratory-scale circulated fluidized bed combustion experiment was conducted to investigate the thermochemical, kinetic and arsenic retention behavior during co-combustion bituminous coal with typical agricultural biomass. Results shown that ignition performance and thermal reactivity of coal could be enhanced by adding biomass in suitable proportion. Arsenic was enriched in fly ash and associated with fine particles during combustion of coal/biomass blends. The emission of arsenic decreased with increasing proportion of biomass in blends. The retention of arsenic may be attributed to the interaction between arsenic and fly ash components. The positive correlation between calcium content and arsenic concentration in ash suggesting that the arsenic-calcium interaction may be regarded as the primary mechanism for arsenic retention.

  7. Reducing Power Penalty Related to PostCombustion CO2 Capture in Coal Power Plants

    Directory of Open Access Journals (Sweden)

    Ramona Mihaela Negoi

    2011-09-01

    Full Text Available Considering the important role of coal in energy security and in the same time the growing need to reduce CO2 emissions, amine-based post-combustion CO2 capture is considered as one of the most proper technologies to be implemented in coal fired power plants as well in natural gas fired plants, refinery gas, cement plants etc.. The main challenge for CO2 post-combustion is reducing the energy demand of the process, especially for solvent regeneration. In this paper, the energy reduction potential when waste heat of flue gases is integrated in the CO2 capture configuration scheme is discussed. The results are compared with a conventional coal power plant configuration when low-steam pressure is extracted from the water-steam cycle of the power plant.

  8. 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.

  9. Influence of Coal Quality on Combustion Performance

    DEFF Research Database (Denmark)

    Lans, Robert Pieter Van Der; Glarborg, Peter; Dam-Johansen, Kim

    1998-01-01

    Three coals have been fired in a tangentially and an opposed fired full scale power plant (about 400 MWe) and in a pilot scale test rig (160 kWt) in order to investigate the influence of coal quality on nitrogen oxide (NO) formation and unburned carbon in relation to furnace design. In-flame and ......Three coals have been fired in a tangentially and an opposed fired full scale power plant (about 400 MWe) and in a pilot scale test rig (160 kWt) in order to investigate the influence of coal quality on nitrogen oxide (NO) formation and unburned carbon in relation to furnace design. In......-flame and furnace gas temperatures have been measured, and substantial differences in temperature between the coals were observed in the full scale furnaces. Identical trends in NO emission as a function of coal type were obtained for the three furnaces. The emissions correlated well with the high temperature...... volatile yield obtained from heated wire mesh analysis. Under air staging conditions the pilot scale test rig was able to reproduce quantitatively the amount of NO from the tangentially fired plant, which operates with over fire air. This is probably due to the relatively small influence of the near burner...

  10. Evaluation of the use of different coals in chemical looping combustion using a bauxite waste as oxygen carrier

    OpenAIRE

    Mendiara, Teresa; García Labiano, Francisco; Gayán Sanz, Pilar; Abad Secades, Alberto; Diego Poza, Luis F. de; Adánez Elorza, Juan

    2013-01-01

    The interest in the use of solid fuels such as coal in Chemical Looping Combustion is growing because of the benefits of the direct use of coal in this technology on the reduction of the costs linked to carbon dioxide capture. In CLC, the oxygen needed for the combustion is supplied by a solid oxygen carrier therefore avoiding the direct contact between fuel and air. Focusing on the use of solid fuels in the In-Situ Gasification Chemical Looping Combustion (iG-CLC), the oxygen ...

  11. Coal blend combustion: fusibility ranking from mineral matter composition

    Energy Technology Data Exchange (ETDEWEB)

    C. Goni; S. Helle; X. Garcia; A. Gordon; R. Parra; U. Kelm; R. Jimenez; G. Alfaro [Universidad de Concepcion, Concepcion (Chile). Departamento de Ingenieria Metalurgica, Instituto de Geologia Economica Aplicada (GEA)

    2003-10-01

    Although coal blends are increasingly utilized at power plants, ash slagging propensity is a non-additive property of the pure coals and hence difficult to predict. Coal ash tendency to slag is related to its bulk chemistry and ash fusion temperatures, and the present study aims to compare the results obtained from thermodynamic simulation with characterization of samples obtained as outcomes of plant-based coal-blend combustion trials at three utilities located in the Centre and North of Chile. Pulverized coal and plant residues samples from five families of binary blends tested in an experimental program were characterized for chemistry, mineralogy and maceral composition. The slagging was evaluated by determination of fusion curves using the MTDATA software and NPLOX3 database for the main coal ash oxides. The ranking obtained was approximately the same as obtained from carbon in the fly ashes and from plant residues observations. The thermodynamic modeling was a valid option to predict the fusibility during the combustion of blends. 16 refs., 7 figs., 1 tab.

  12. Plasma Torch for Plasma Ignition and Combustion of Coal

    Science.gov (United States)

    Ustimenko, Alexandr; Messerle, Vladimir

    2015-09-01

    Plasma-fuel systems (PFS) have been developed to improve coal combustion efficiency. PFS is a pulverized coal burner equipped with arc plasma torch producing high temperature air stream of 4000 - 6000 K. Plasma activation of coal at the PFS increases the coal reactivity and provides more effective ignition and ecologically friendly incineration of low-rank coal. The main and crucial element of PFS is plasma torch. Simplicity and reliability of the industrial arc plasma torches using cylindrical copper cathode and air as plasma forming gas predestined their application at heat and power engineering for plasma aided coal combustion. Life time of these plasma torches electrodes is critical and usually limited to 200 hours. Considered in this report direct current arc plasma torch has the cathode life significantly exceeded 1000 hours. To ensure the electrodes long life the process of hydrocarbon gas dissociation in the electric arc discharge is used. In accordance to this method atoms and ions of carbon from near-electrode plasma deposit on the active surface of the electrodes and form electrode carbon condensate which operates as ``actual'' electrode. Complex physicochemical investigation showed that deposit consists of nanocarbon material.

  13. Combustion velocity of coal in seat of an underground fire

    Energy Technology Data Exchange (ETDEWEB)

    Yanchenko, G.A.; Kuzyaev, L.S.; Serra-Suares, L.Kh.

    1988-02-01

    Using the example of an underground fire in a very long coal channel, analyzes the processes of energy interchange between the gas phase and the coal surface in the channel and explains that calculations to assess the duration of burning (and hence assist in extinguishing or containing the fire) need to be able to account for the speed of transition of the coal from the solid phase (burning mass) to the gaseous phase in conditions of oxygen (in the form of products of complete combustion), reduction and dry distillation (in the form of products of incomplete combustion). Demonstrates in formulaic form the correlation between the mass velocity of the coal burning, the volume velocity of the arrival of air at the seat of the fire, the excess oxidant coefficient and the volume of air which is theoretically required to completely burn 1 kg of coal and presents the coefficients of excess oxygen and a generalized, statistical coefficient averaged for eight basic coal groups in tabular form. 1 ref.

  14. Minimum secure speed of fully mechanized coal face based on critical temperature of coal spontaneous combustion

    Institute of Scientific and Technical Information of China (English)

    Wei LIU; Yue-Ping QIN; Yong-Jiang HAO; Tian-Zhu GUI; Jing-Yan JIA

    2013-01-01

    The critical temperature theory of spontaneous combustion of coal and the numerical simulation method are used to explore the minimum secure speed of fully mechanized coal face to prevent the spontaneous combustion in goaf.Combined with the actual situation of workface 31005 in a coal mine,the highest temperatures in goaf at different advancing speeds were obtained by the numerical simulation of spontaneous combustion in goaf,and then a power function equation between the highest temperature and the advancing speed was achieved by regression analysis.The advancing speed corresponding to the critical temperature value was taken as the minimum safe speed of workface based on the equation.Finally,the accuracy and reliability of the speed were verified by the actual advancing process of workface 31005.The results of this research show that the new judgment method of the minimum safety speed has a higher value to be applied in the field.

  15. NO Reduction over Biomass and Coal Char during Simultaneous Combustion

    DEFF Research Database (Denmark)

    Zhao, Ke; Glarborg, Peter; Jensen, Anker Degn

    2013-01-01

    . The straw and bark chars showed higher reactivity, about a factor of 4–5, than bituminous char at 850 °C. The difference in reactivity between biomass char and bituminous char decreased with increasing reaction temperature. The reaction rate expressions for NO reduction during simultaneous combustion......This paper reports an experimental study of NO reduction over chars of straw, bark, bituminous coal, and lignite. The experiments were performed in a fixed bed reactor in the temperature range 850–1150 °C. The chars were generated by in situ pyrolysis at the reaction temperature to minimize further...... thermal deactivation. The rates of NO reduction over char were studied by char combustion experiments and O2-free experiments respectively. Two simple models were applied to interpret the data from the char combustion experiments. One model assumed that combustion and NO release take place uniformly...

  16. 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.

  17. 6th Conference on Coal Utilization Technology; Dai 6 kai sekitan riyo gijutsu kaigi koenshu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    The paper compiled the papers presented in the 6th Conference on Coal Utilization Technology held in September 1996. With relation to the fluidized bed boiler, reported were Field operation test of Wakamatsu PFBC combined cycle power plant and Development of pressurized internally circulating fluidized bed combustion technology. Regarding the coal reformation, Development of advanced coal cleaning process, Coal preparation and coal cleaning in the dry process, etc. Concerning the combustion technology, Study of the O2/CO2 combustion technology, Development of pressurized coal partial combustor, etc. About the CWM, Development of low rank coals upgrading and their CWM producing technology, Technique of CWM distribution system, etc. Relating to the coal ash, Engineering characteristics of the improved soil by deep mixing method using coal ash, Employment of fluidized bed ash as a basecourse material, On-site verification trials using fly ash for reclamation behind bulkheads, Water permeabilities of pulverized fuel ash, Separation of unburned carbon from coal fly ash through froth flotation, Practical use technology of coal ash (POZ-O-TEC), etc

  18. TOXIC SUBSTANCES FROM COAL COMBUSTION A COMPREHENSIVE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    A KOLKER; AF SAROFIM; CA PALMER; FE HUGGINS; GP HUFFMAN; J LIGHTY; JJ HELBLE; JOL WENDT; MR AMES; N YAP; R FINKELMAN; R. MAMANI-PACO; SJ MROCZKOWSKY; T PANAGIOTOU; W SEAMES

    1999-01-28

    The technical objectives of this project are: (a) To identify the effect of the mode-of-occurrence of toxic elements in coal on the partitioning of these elements among vapor, submicron fume, and fly ash during the combustion of pulverized coal, (b) To identify the mechanisms governing the post-vaporization interaction of toxic elements and major minerals or unburnt char, (c) To determine the effect of combustion environment (i.e., fuel rich or fuel lean) on the partitioning of trace elements among vapor, submicron fume, and fly ash during the combustion of pulverized coal, (d) To model the partitioning of toxic elements among various chemical species in the vapor phase and between the vapor phase and complex aluminosilicate melts, (e) To develop the new Toxics Partitioning Engineering Model (ToPEM), applicable to all combustion conditions including new fuels and coal blends, low-NO{sub x} combustion systems, and new power generation plants. A description of the work plan for accomplishing these objectives is presented in Section 2.1 of this report. The work discussed in this report covers the reporting period from 1 October 1998 to 31 December 1998. During this quarter, basic coal testing at USGS was completed. Total sulfur contents range from 0.43 wt-% in the Wyodak to 2.68 wt-% in the Ohio sample. In the North Dakota and Ohio samples, about half of the total sulfur is pyritic and half is organic. The North Dakota sample also contains a minor amount of sulfate, consistent with the presence of barite in this sample. In the Wyodak sample, the majority of the sulfur is organic. Preliminary mineralogy of the three Phase II coals was determined by SEM/EDX. The Ohio coal contains all of the five most common major phases: quartz, illitic clay, kaolinitic clay, pyrite and calcite. Based on this preliminary work, the North Dakota sample appears to lack both kaolinite and calcite, and the Wyodak sample appears to lack calcite. Subsequent SEM work will attempt to reconfirm

  19. Combustion and NOx Emission Behavior of Chinese Coals

    Institute of Scientific and Technical Information of China (English)

    CHENHonggang; XIEKechang

    2002-01-01

    Seven Chinese coals ranking from anthracite to sub-bituminous from the Shanxi province were selected for study to forecast the combustion and NOx emission behavior.Three UK,one Indonesia and one South Africa coal was included in the study for reference.A flat flame-turbulent jet apparatus was employed to assess flame stability,ignition performance and NOx emission behavior for the initial stage of devolatilization and combustion. This apparatus can simulate particle heating rates,maximum temperatures and the influence of the turbulent fluid interactionson the fate of volatiles.To simulate processes occurring over longer residence time, additional devolatilization experiments were performed in a drop tube furnace.Char reactivity was studied through thermogravimetric analysis.Finally,fouling propensity was studied with the aid of a purpose-built laboratory combustor that enabled the characteristics of the ash deposit to be assessed empirically.The results show that Chinese coals do not appear to possess unusual features in respect of NOx formation,flame stability and ignition,char burnout and ash slagging.The range of coals available in China appears sufficiently broad that suits all requirements.In particular,Shenfu coal,with its initial fast devolatilization and nitrogen release rates and its low initial nitrogen content and high char reactivity,will perform well when fired in industrial boilers as far as NOx emission,flame stability and combustion efficiency are concerned.Pingshuo coal exhibits high char reactivity and an attractive slagging performance suggesting that this fuel represents a good compromise between NOx emission and overall plant efficiency.

  20. Kinetics of Coal Char Combustion in Oxygen-Enriched Environment

    Science.gov (United States)

    Czakiert, T.; Nowak, W.

    The influence of oxygen-enriched gaseous atmosphere on coal char combustion was studied. Two different coals, i.e. lignite and bituminous coal, were used as a basic fuel and the reacting gases of oxygen & CO2 were used to simulate flue gas recirculation. Moreover, a broad range of in-furnace conditions, i.e. five temperatures of 873, 973, 1073, 1173, 1273K and five oxygen concentrations of 20, 40, 60, 80, 100%vol., was investigated. Thermogravimetric method of measurement was employed to obtain the processing data on fuel conversion rate under foregoing investigated conditions. For further calculations, simplified Shrinking-Core Model was introduced. Finally, fundamental kinetic parameters, i.e. pre-exponential factor, activation energy and reaction order, were established and then on the basis of their values reaction-controlling regime for coal char combustion in oxygen-enriched environment was predicted. The investigations, financially supported by Polish Government, are a part of Framework Project "Supercritical Coal-fired Power Units".

  1. Grindability and combustion behavior of coal and torrefied biomass blends.

    Science.gov (United States)

    Gil, M V; García, R; Pevida, C; Rubiera, F

    2015-09-01

    Biomass samples (pine, black poplar and chestnut woodchips) were torrefied to improve their grindability before being combusted in blends with coal. Torrefaction temperatures between 240 and 300 °C and residence times between 11 and 43 min were studied. The grindability of the torrefied biomass, evaluated from the particle size distribution of the ground sample, significantly improved compared to raw biomass. Higher temperatures increased the proportion of smaller-sized particles after grinding. Torrefied chestnut woodchips (280 °C, 22 min) showed the best grinding properties. This sample was blended with coal (5-55 wt.% biomass). The addition of torrefied biomass to coal up to 15 wt.% did not significantly increase the proportion of large-sized particles after grinding. No relevant differences in the burnout value were detected between the coal and coal/torrefied biomass blends due to the high reactivity of the coal. NO and SO2 emissions decreased as the percentage of torrefied biomass in the blend with coal increased.

  2. Impact of nongray multiphase radiation in pulverized coal combustion

    Science.gov (United States)

    Roy, Somesh; Wu, Bifen; Modest, Michael; Zhao, Xinyu

    2016-11-01

    Detailed modeling of radiation is important for accurate modeling of pulverized coal combustion. Because of high temperature and optical properties, radiative heat transfer from coal particles is often more dominant than convective heat transfer. In this work a multiphase photon Monte Carlo radiation solver is used to investigate and to quantify the effect of nongray radiation in a laboratory-scale pulverized coal flame. The nongray radiative properties of carrier phase (gas) is modeled using HITEMP database. Three major species - CO, CO2, and H2O - are treated as participating gases. Two optical models are used to evaluate radiative properties of coal particles: a formulation based on the large particle limit and a size-dependent correlation. Effect of scattering due to coal particle is also investigated using both isotropic scattering and anisotropic scattering using a Henyey-Greenstein function. Lastly, since the optical properties of ash is very different from that of coal, the effect of ash content on the radiative properties of coal particle is examined. This work used Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation Grant Number ACI-1053575.

  3. Detection and Control Technology of Spontaneous Combustion Area in Coal Rejects Dump of Xiqu Mine%西曲煤矿矸石山自燃火区探测及治理技术

    Institute of Scientific and Technical Information of China (English)

    曾凡宇; 田云福; 芦根玲; 樊少武; 姚海飞

    2012-01-01

    According to the proldem that the spontaneous combusted coal rejects dump would send out the harmful gas to pollute environ- ment and could have explosion dangers, thus a comprehensive fire distinguishing was conducted to the serious spontaneous combusted coal rejects dump in Xiqu Mine in order to purify the environment and eliminate the danger purposes. The comprehensive detection technology with the infrared temperature measurement, multi parameters gas detection and borehole temperature measurement was applied to deter- mine the fire distribution at the east side of the coal rejects dump with an area of 650 m2. An rational layout of grouting boreholes, grou- ting parameters determined, fly ash from coal-fired power plant and the new fire prevention and control material was applied to the fire ex- tinguishing with grouting. The fire prevention and control results showed that the CO volume fraction in the coal rejects dump was reduced from 840x10-6 to 12x10-6 , the H2S volume fraction was reduced from 89x10-6 closed to 0 and the SO2 volume fraction was 0. The surface temperature of the coal rejects dump and the local temperature was the same and the internal temperature was reduced from 420℃ below to 80 ℃. Those results could meet the requirements stipulated in Disaster Prevention and Control Standard of Coal Rejects Dump in mine.%针对自燃的矸石山散发出有害气体污染环境,还有可能发生爆炸的问题,对自燃严重的西曲煤矿矸石山进行综合灭火,以达到净化环境、消除危险的目的。采用红外测温、多参数气体检测和钻孔测温相结合的综合探测技术,确定火区分布于矸石山的东侧,面积为650 m2,进而合理布置注浆钻孔,确定注浆参数,选用电厂粉煤灰与新型防灭火材料对火区进行注浆灭火。治理结果表明:矸石山的CO体积分数从840伊10-6降至12伊10-6,H2S体积分数从89伊10-6降至趋近于0,SO2体积分数为0,矸石山表面温度与当地气

  4. 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.

  5. Prospects for coal and clean coal technology in the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-03-15

    This report examines the current energy outlook for the Philippines in regard not only to coal but also other energy resources. The history of the power sector, current state of play and future plans to meet the increasing energy demand from a growing population are discussed. There is also analysis of the trends for coal demand and production, imports and exports of coal and the types of coal-fired power stations that have been built. This includes examination of the legislation involving coal and the promotion of clean coal technologies.

  6. Notes on Contributions to the Science of Rare Earth Element Enrichment in Coal and Coal Combustion Byproducts

    Directory of Open Access Journals (Sweden)

    James C. Hower

    2016-03-01

    Full Text Available Coal and coal combustion byproducts can have significant concentrations of lanthanides (rare earth elements. Rare earths are vital in the production of modern electronics and optics, among other uses. Enrichment in coals may have been a function of a number of processes, with contributions from volcanic ash falls being among the most significant mechanisms. In this paper, we discuss some of the important coal-based deposits in China and the US and critique classification systems used to evaluate the relative value of the rare earth concentrations and the distribution of the elements within the coals and coal combustion byproducts.

  7. The effect of imported coals and coal blends on grinding and combustion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Maier, H.; Rebmann, M.; Fingerle, A.; Hein, K.R.G. [University of Stuttgart, Stuttgart (Germany). Inst.-IVD

    1998-12-31

    The European Union is one of the biggest regions importing bituminous coal from overseas areas and countries like South Africa, Australia, Colombia, North America, and Indonesia/Asia. The use of these coals can raise specific problems with regard to the milling and combustion behaviour. In this project the following facilities were used for the test trials; a 120 kg/h impact milling system to investigate the milling behaviour; the 0.5 MW{sub th} IVD semi-industrial scale pulverised combustion chamber for the combustion studies and; a 80 kW{sub th} turbulent natural gas free jet burner, for the characterisation studies. The results concerning the milling behaviour show that most of the tested coals and coal blending the Hardgrove Index is a measure to determine the grindability on laboratory scale but also not generally valid. The coal characterization studies with the turbulent gas burner show that the heat up-rate and the devolatilization of the volatiles is comparable to those in full scale coal flames. The volatile release is about 10 times faster compared to values determined with electricity heated flow reactors. 11 refs., 33 figs., 5 tabs.

  8. Nitrogen Chemistry in Fluidized Bed Combustion of Coal

    DEFF Research Database (Denmark)

    Jensen, Anker Degn

    The present Ph.D thesis describes an experimental and theoretical investigation of the formation and destruction of nitrogen oxides (NOx and N2O) in fluidized bed combustion (FBC) of coal. A review of the current knowledge of nitrogen chemistry in FBC is presented. The review covers both laboratory...... and reduction by homogeneous and heterogeneous reactions. The data for the estimation of kinetics of the heterogeneous reactions were measured by one of the partners in the project for char and bed material sampled from a pressurized FBC pilot plant burning Kiveton Park coal. Experimental data from the pilot...... identified. Laboratory measurements showed that 50 % of the fuel-N stays in the char after devolatilization and in the model it is assumed that this is oxidized to NO during char combustion. A significant amount of NO, 10-18 % of the fuel-N, was formed by oxidation of NH3 catalyzed by bed material...

  9. Combustion studies of coal derived solid fuels by thermogravimetric analysis. III. Correlation between burnout temperature and carbon combustion efficiency

    Science.gov (United States)

    Rostam-Abadi, M.; DeBarr, J.A.; Chen, W.T.

    1990-01-01

    Burning profiles of 35-53 ??m size fractions of an Illinois coal and three partially devolatilized coals prepared from the original coal were obtained using a thermogravimetric analyzer. The burning profile burnout temperatures were higher for lower volatile fuels and correlated well with carbon combustion efficiencies of the fuels when burned in a laboratory-scale laminar flow reactor. Fuels with higher burnout temperatures had lower carbon combustion efficiencies under various time-temperature conditions in the laboratory-scale reactor. ?? 1990.

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

    Institute of Scientific and Technical Information of China (English)

    文虎; 徐精彩; 葛岭梅

    2001-01-01

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

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

    Institute of Scientific and Technical Information of China (English)

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

    2001-01-01

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

  12. Modeling of Pulverized Coal Combustion in Cement Rotary Kiln

    OpenAIRE

    2006-01-01

    In this paper, based on analysis of the chemical and physical processes of clinker formation, a heat flux function was introduced to take account of the thermal effect of clinker formation. Combining the models of gas-solid flow, heat and mass transfer, and pulverized coal combustion, a set of mathematical models for a full-scale cement rotary kiln were established. In terms of commercial CFD code (FLUENT), the distributions of gas velocity, gas temperature, and gas components in a cement rot...

  13. Low-NO/SUB/x combustion of coal by vertical cyclone furnace (II): slag tap combustion experiments

    Energy Technology Data Exchange (ETDEWEB)

    Ichikawa, M.; Kusakabe, T.; Matsumoto, T.; Miyajima, K.; Yamazaki, M.

    1983-01-01

    Slag tap combustion of coal was investigated in the hope of developing a method of low-NOx, low-dust combustion. Miike coal (heating value 7000 kcal/kg) was combusted with air preheated to approximately 650 C in the same experimental vertical cyclone furnace as that used in the previous study. The furnace temperature rose to 1510-1740 C and trouble-free slag tap combustion was achieved. The concentration of NO in the flue gas fell sharply with decreasing excess air ratio in the primary combustion chamber. 2 references.

  14. Coal slurry combustion optimization on single cylinder engine. Task 1.1.2.2.2, Combustion R&D

    Energy Technology Data Exchange (ETDEWEB)

    1992-09-01

    Under the sponsorship of the US Department of Energy, Morgantown Energy Technology Center, GE Transportation System has been conducting a proof of concept program to use coal water slurry (CWS) fuel to power a diesel engine locomotive since 1988. As reported earlier [1], a high pressure electronically controlled accumulator injector using a diamond compact insert nozzle was developed for this project. The improved reliability and durability of this new FIE allowed for an improved and more thorough study of combustion of CWS fuel in a diesel engine. It was decided to include a diesel pilot fuel injector in the combustion system mainly due to engine start and low load operation needs. BKM, Inc. of San Diego, CA was contracted to develop the electronic diesel fuel pilot/starting FIE for the research engine. As a result, the experimental combustion study was very much facilitated due to the ability of changing pilot/CWS injection timings and quantities without having to stop the engine. Other parameters studied included combustion chamber configuration (by changing CWS fuel injector nozzle hole number/shape/angle), as well as injection pressure. The initial phase of this combustion study is now complete. The results have been adopted into the design of a 12 cylinder engine FIE, to be tested in 1992. This paper summarizes the main findings of this study.

  15. Pressurised coal combustion in a pilot scale facility

    Energy Technology Data Exchange (ETDEWEB)

    Hardalupas, Y.; Prassas, I.; Taylor, A.M.K.P.; Whitelaw, J.H. [Imperial College of Science, Technology and Medicine, London (United Kingdom). Mechanical Engineering Dept.

    1998-12-31

    Flux, velocity and the temperature characteristics of burning coal particles were measured simultaneously in the primary combustion zone of the swirl-stabilised burner of the pilot-scale furnace constructed at Imperial College. The furnace was designed to operate at pressures up to 5 bar and at thermal loadings up to 150 kW, and provision was made for optical access in the near-burner region of the combustor. The combined instrument used a novel technique for the simultaneous measurement of velocity and size, as well as the angle between the trajectory of the particle and an axis of reference, of particles of arbitrary shape, the so-called Shadow Doppler Velocimeter; and a two-colour pyrometer, for the simultaneous measurement of velocity, size and temperature of burning pulverised coal particles. The experiments performed consisted of: measurement of the gaseous phase as a function of the swirl number; measurement of the size, velocity, and temperature of burning coal particles as a function of the swirl number; and measurement of the size and velocity of burning coal particles inside the pressurised coal combustor at atmospheric pressure. The experiments were to evaluate and improve and further develop existing instrumentation with potential to be used in pressurised combustors; provide a database of accurate measurements for the needs of numerical models; and improve the understanding of the fluid mechanics and combustion processes at atmospheric pressures. Results obtained using the optical instrumentation showed that in an open flame, evidence of particle centrifuging existed downstream of the quarl entry. The temperature of volatile flames was about 2250 K and that of the char below 2000 K. Measurements along radial profiles inside the coal combustor showed that the axial and tangential velocity of the particles was almost independent of size. 19 refs., 15 figs., 1 tab.

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

    Directory of Open Access Journals (Sweden)

    Belošević Srđan V.

    2016-01-01

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

  17. The effects of pf grind quality on coal burnout in a 1 MW combustion test facility

    Energy Technology Data Exchange (ETDEWEB)

    Richelieu Barranco; Michael Colechin; Michael Cloke; Will Gibb; Edward Lester [University of Nottingham, Nottingham (United Kingdom). School of Chemical, Environmental and Mining Engineering, Nottingham Fuel and Energy Centre

    2006-05-15

    A study was carried out to determine the effect of pf particle size distribution on coal burnout propensity in a 1 MW pulverised fuel burner. The specific aim of the work was to assess the improvement in combustion performance achievable by retrofitting commercially available high performance static or dynamic classifiers to existing plants. Two coals were used and were selected as representative of extremes in fuel characteristics experienced by coal importing utilities in Europe. Each coal was fired in the unit at a range of grind sizes to determine the overall impact of a variable performance from a mill. The levels of unburnt carbon in the resultant flyashes for the two coals showed significantly different behaviour. For the higher volatile coal, the unburnt carbon was found to be insensitive to grind quality. However, the coarser grinds of the other coal produced significantly lower unburnt carbon than expected when compared with the finest grinds. Generally the results indicate that the installation of improved classification technology, leading to a finer product, will help to lower unburnt carbon levels. Nevertheless, further work will be necessary to establish the levels of diminishing returns for grind size, burnout performance and grind costs. 21 refs., 4 figs., 4 tabs.

  18. Low—NOx Combustion and Experimental Investigation in a ROtary Type Pulverized Coal Classifier

    Institute of Scientific and Technical Information of China (English)

    WenjunKong; ShangmoCheng; 等

    1995-01-01

    In order to improve the combustion conditions,maximize the carbon burnout for low-NOx firing systems and meet the requirements for ignition and flame stabilization as low volatile and low quality coal are burned in boilers,finer pulverzed coal should be used .Hence.it is of great practical importance to study the rotary type classifier for the MPS type medium-speed mill.In this pper,we first review the low-NOx combustion technology,then some model tests of rotating classifier are completed.The results show that the classifier performances are very satisfactory,with the fineness of the finished produce being R90f<10%,Rules for designing and controlling rotating classifier are also developed in this paper.

  19. Soot, organics, and ultrafine ash from air- and oxy-fired coal combustion

    Data.gov (United States)

    U.S. Environmental Protection Agency — Pulverized bituminous coal was burned in a 10W externally heated entrained flow furnace under air-combustion and three oxy-combustion inlet oxygen conditions (28,...

  20. Coal India Limited - technology strategy to meet the challenges of future

    Energy Technology Data Exchange (ETDEWEB)

    Narayanan, S.M.P.; Misra, S.B.C.

    1989-08-01

    The production increases of the next 5 and 10 years are challenges to Coal India. Organized and planned efforts are called for. Coal India is well aware of it and has started gearing itself up to meet the challenges right now. The proposed strategy is as follows: development and adoption of new technologies through indigenous means and by import wherever necessary; upgradation of technology; wider application of new/upgraded technologies already established; commercialization of technologies established with R D work; and R D work. The major areas where work on this strategy has been taken up are: coal exploration; shaft sinking, mine development and mine construction; underground mining; opencast mining; coal handling dispatch; coal beneficiation; coal combustion utilization; slurry pipeline transport of coal; environmental management; and electronics for coal sector, including surface telecommunication network, data base management (computer), and mining electronics, safety, communication and industrial electronics. This paper briefly describes the work being done in each of these areas.

  1. Development of coal energy utilization technologies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    Coal liquefaction produces new and clean energy by performing hydrogenation, decomposition and liquefaction on coal under high temperatures and pressures. NEDO has been developing bituminous coal liquefaction technologies by using a 150-t/d pilot plant. It has also developed quality improving and utilization technologies for liquefied coal, whose practical use is expected. For developing coal gasification technologies, construction is in progress for a 200-t/d pilot plant for spouted bed gasification power generation. NEDO intends to develop coal gasification composite cycle power generation with high efficiency and of environment harmonious type. This paper summarizes the results obtained during fiscal 1994. It also dwells on technologies to manufacture hydrogen from coal. It further describes development of technologies to manufacture methane and substituting natural gas (SNG) by hydrogenating and gasifying coal. The ARCH process can select three operation modes depending on which of SNG yield, thermal efficiency or BTX yield is targeted. With respect to promotion of coal utilization technologies, description is given on surveys on development of next generation technologies for coal utilization, and clean coal technology promotion projects. International coal utilization and application projects are also described. 9 figs., 3 tabs.

  2. Thermal behaviour and kinetics of coal/biomass blends during co-combustion.

    Science.gov (United States)

    Gil, M V; Casal, D; Pevida, C; Pis, J J; Rubiera, F

    2010-07-01

    The thermal characteristics and kinetics of coal, biomass (pine sawdust) and their blends were evaluated under combustion conditions using a non-isothermal thermogravimetric method (TGA). Biomass was blended with coal in the range of 5-80 wt.% to evaluate their co-combustion behaviour. No significant interactions were detected between the coal and biomass, since no deviations from their expected behaviour were observed in these experiments. Biomass combustion takes place in two steps: between 200 and 360 degrees C the volatiles are released and burned, and at 360-490 degrees C char combustion takes place. In contrast, coal is characterized by only one combustion stage at 315-615 degrees C. The coal/biomass blends presented three combustion steps, corresponding to the sum of the biomass and coal individual stages. Several solid-state mechanisms were tested by the Coats-Redfern method in order to find out the mechanisms responsible for the oxidation of the samples. The kinetic parameters were determined assuming single separate reactions for each stage of thermal conversion. The combustion process of coal consists of one reaction, whereas, in the case of the biomass and coal/biomass blends, this process consists of two or three independent reactions, respectively. The results showed that the chemical first order reaction is the most effective mechanism for the first step of biomass oxidation and for coal combustion. However, diffusion mechanisms were found to be responsible for the second step of biomass combustion.

  3. Mercury stable isotope signatures of world coal deposits and historical coal combustion emissions.

    Science.gov (United States)

    Sun, Ruoyu; Sonke, Jeroen E; Heimbürger, Lars-Eric; Belkin, Harvey E; Liu, Guijian; Shome, Debasish; Cukrowska, Ewa; Liousse, Catherine; Pokrovsky, Oleg S; Streets, David G

    2014-07-01

    Mercury (Hg) emissions from coal combustion contribute approximately half of anthropogenic Hg emissions to the atmosphere. With the implementation of the first legally binding UNEP treaty aimed at reducing anthropogenic Hg emissions, the identification and traceability of Hg emissions from different countries/regions are critically important. Here, we present a comprehensive world coal Hg stable isotope database including 108 new coal samples from major coal-producing deposits in South Africa, China, Europe, India, Indonesia, Mongolia, former USSR, and the U.S. A 4.7‰ range in δ(202)Hg (-3.9 to 0.8‰) and a 1‰ range in Δ(199)Hg (-0.6 to 0.4‰) are observed. Fourteen (p coal Hg emissions tracing. A revised coal combustion Hg isotope fractionation model is presented, and suggests that gaseous elemental coal Hg emissions are enriched in the heavier Hg isotopes relative to oxidized forms of emitted Hg. The model explains to first order the published δ(202)Hg observations on near-field Hg deposition from a power plant and global scale atmospheric gaseous Hg. Yet, model uncertainties appear too large at present to permit straightforward Hg isotope source identification of atmospheric forms of Hg. Finally, global historical (1850-2008) coal Hg isotope emission curves were modeled and indicate modern-day mean δ(202)Hg and Δ(199)Hg values for bulk coal emissions of -1.2 ± 0.5‰ (1SD) and 0.05 ± 0.06‰ (1SD).

  4. Small scale experiment on the plasma assisted thermal chemical preparation and combustion of pulverized coal

    Energy Technology Data Exchange (ETDEWEB)

    Masaya, Sugimoto; Koichi, Takeda [Akita Prefectural University (Japan); Solonenko, O.P. [Institute of Theoretical and Applied Mechanics, Novosibirsk (Russian Federation); Sakashita, M.; Nakamura, M. [Japan Technical Information Service, Tokyo (Japan)

    2001-07-01

    Ignition and stable combustion of pulverized coal with Nitrogen and Air plasmas are investigated experimentally for some different types of coal. The experimental results show that air plasma has strong effect for ignition and stabilization of coal combustion. In addition, suppression of NO{sub x} production could be possible even in air plasma. It is possible to ignite and burn stably for the inferior coal that contains volatile matter in the ratio of only 10% of dry total mass. (authors)

  5. Study and application of plasticity plaster-slurry for preventing coal spontaneous combustion

    Institute of Scientific and Technical Information of China (English)

    LIU Ai-hua(刘爱华); CAI Kang-xu(蔡康旭); GUO Da(郭达); ZHANG Fu-sheng(张复胜)

    2003-01-01

    Introduced the modulation scheme, function and mechanism of plasticity plaster-slurry preventing coal spontaneous combustion. The applications show that the plasticity plaster-slurry has good hygroscopicity and adsorptivity. To spray it on the coal wall of tunnel can shut off leakage wind fast and effectively. To press it into the coal body can absorb the heat and descend the temperature, surround the coal pieces, eliminate the possibility of the fiery district resuming combustion.

  6. Temporal measurements and kinetics of selenium release during coal combustion and gasification in a fluidized bed.

    Science.gov (United States)

    Shen, Fenghua; Liu, Jing; Zhang, Zhen; Yang, Yingju

    2016-06-05

    The temporal release of selenium from coal during combustion and gasification in a fluidized bed was measured in situ by an on-line analysis system of trace elements in flue gas. The on-line analysis system is based on an inductively coupled plasma optical emission spectroscopy (ICP-OES), and can measure concentrations of trace elements in flue gas quantitatively and continuously. The results of on-line analysis suggest that the concentration of selenium in flue gas during coal gasification is higher than that during coal combustion. Based on the results of on-line analysis, a second-order kinetic law r(x)=0.94e(-26.58/RT)(-0.56 x(2) -0.51 x+1.05) was determined for selenium release during coal combustion, and r(x)=11.96e(-45.03/RT)(-0.53 x(2) -0.56 x+1.09) for selenium release during coal gasification. These two kinetic laws can predict respectively the temporal release of selenium during coal combustion and gasification with an acceptable accuracy. Thermodynamic calculations were conducted to predict selenium species during coal combustion and gasification. The speciation of selenium in flue gas during coal combustion differs from that during coal gasification, indicating that selenium volatilization is different. The gaseous selenium species can react with CaO during coal combustion, but it is not likely to interact with mineral during coal gasification.

  7. Effects of electrical resistance on the spontaneous combustion tendency of coal and the interaction matrix concept

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    There have been several developments in determining the spontaneous combustion liability of coal. Most of the methods of concern have purely been based on the internal properties of the coal itself. The relation between the crossing-point method and the electrical resistance of coal was examined here to outline the spontaneous combustion tendency of coal. The electrical resistance property of coal was looked into as a decision-making parameter of the interaction matrix concept for the final decision on the spontaneous combustion tendency.

  8. Effect of multiphase radiation on coal combustion in a pulverized coal jet flame

    Science.gov (United States)

    Wu, Bifen; Roy, Somesh P.; Zhao, Xinyu; Modest, Michael F.

    2017-08-01

    The accurate modeling of coal combustion requires detailed radiative heat transfer models for both gaseous combustion products and solid coal particles. A multiphase Monte Carlo ray tracing (MCRT) radiation solver is developed in this work to simulate a laboratory-scale pulverized coal flame. The MCRT solver considers radiative interactions between coal particles and three major combustion products (CO2, H2O, and CO). A line-by-line spectral database for the gas phase and a size-dependent nongray correlation for the solid phase are employed to account for the nongray effects. The flame structure is significantly altered by considering nongray radiation and the lift-off height of the flame increases by approximately 35%, compared to the simulation without radiation. Radiation is also found to affect the evolution of coal particles considerably as it takes over as the dominant mode of heat transfer for medium-to-large coal particles downstream of the flame. To investigate the respective effects of spectral models for the gas and solid phases, a Planck-mean-based gray gas model and a size-independent gray particle model are applied in a frozen-field analysis of a steady-state snapshot of the flame. The gray gas approximation considerably underestimates the radiative source terms for both the gas phase and the solid phase. The gray coal approximation also leads to under-prediction of the particle emission and absorption. However, the level of under-prediction is not as significant as that resulting from the employment of the gray gas model. Finally, the effect of the spectral property of ash on radiation is also investigated and found to be insignificant for the present target flame.

  9. 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.

  10. Thermally induced structural changes in coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Gavalas, G.R.; Flagan, R.C.

    1990-01-17

    The effect of particle shape on char burnout is investigated in the limit of shrinking core combustion. As a first step, the particle temperature is assumed to proceed in the shrinking core regime and under conditions of negligible Stefan flow. The problem then reduces to calculating the oxygen concentration field around a non-spherical particle with the oxidation reaction taking place on the external surface. This problem has been addressed by an analytical technique and a numerical technique. An analytical technique known as domain perturbation'' was used to examine the change due to reaction in the shape of a slightly nonspherical, but axisymmetric, particle. It was found that the aspect ratio always increases with conversion, i.e., the particle becomes less spherical. A numerical technique, based on the boundary integral'' method was developed to handle the case of an axisymmetric particle with otherwise arbitrary shape. Numerical results are presented which again show the aspect ratio to increase with conversion. 8 refs.

  11. Coal surface control for advanced physical fine coal cleaning technologies

    Energy Technology Data Exchange (ETDEWEB)

    Morsi, B.I.; Chiang, S.H.; Sharkey, A.; Blachere, J.; Klinzing, G.; Araujo, G.; Cheng, Y.S.; Gray, R.; Streeter, R.; Bi, H.; Campbell, P.; Chiarlli, P.; Ciocco, M.; Hittle, L.; Kim, S.; Kim, Y.; Perez, L.; Venkatadri, R.

    1992-01-01

    This final report presents the research work carried out on the Coal Surface Control for Advanced Physical Fine Coal Cleaning Technologies project, sponsored by the US Department of Energy, Pittsburgh Energy Technology Center (DOE/PETC). The project was to support the engineering development of the selective agglomeration technology in order to reduce the sulfur content of US coals for controlling SO[sub 2] emissions (i.e., acid rain precursors). The overall effort was a part of the DOE/PETCs Acid Rain Control Initiative (ARCI). The overall objective of the project is to develop techniques for coal surface control prior to the advanced physical fine coal cleaning process of selective agglomeration in order to achieve 85% pyrite sulfur rejection at an energy recovery greater than 85% based on run-of-mine coal. The surface control is meant to encompass surface modification during grinding and laboratory beneficiation testing. The project includes the following tasks: Project planning; methods for analysis of samples; development of standard beneficiation test; grinding studies; modification of particle surface; and exploratory R D and support. The coal samples used in this project include three base coals, Upper Freeport - Indiana County, PA, Pittsburgh NO. 8 - Belmont County, OH, and Illinois No. 6 - Randolph County, IL, and three additional coals, Upper Freeport - Grant County- WV, Kentucky No. 9 Hopkins County, KY, and Wyodak - Campbell County, WY. A total of 149 drums of coal were received.

  12. Characterization of feed coal and coal combustion products from power plants in Indiana and Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    Brownfield, M.E.; Affolter, R.H.; Cathcart, J.D.; O' Connor, J.T.; Brownfield, I.K.

    1999-07-01

    The US Geological Survey, Kentucky Geological Survey, and the University of Kentucky Center for Applied Energy Research are collaborating with Indiana and Kentucky utilities to determine the physical and chemical properties of feed coal and coal combustion products (CCP) from three coal-fired power plants. These three plants are designated as Units K1, K2, and I1 and burn high-, moderate-, and low-sulfur coals, respectively. Over 200 samples of feed coal and CCP were analyzed by various chemical and mineralogical methods to determine mode of occurrence and distribution of trace elements in the CCP. Generally, feed coals from all 3 Units contain mostly well-crystallized kaolinite and quartz. Comparatively, Unit K1 feed coals have higher amounts of carbonates, pyrite and sphalerite. Unit K2 feed coals contain higher kaolinite and illite/muscovite when compared to Unit K1 coals. Unit I1 feed coals contain beta-form quartz and alumino-phosphates with minor amounts of calcite, micas, anatase, and zircon when compared to K1 and K2 feed coals. Mineralogy of feed coals indicate that the coal sources for Units K1 and K2 are highly variable, with Unit K1 displaying the greatest mineralogic variability; Unit I1 feed coal however, displayed little mineralogic variation supporting a single source. Similarly, element contents of Units K1 and K2 feed coals show more variability than those of Unit I1. Fly ash samples from Units K1 and K2 consist mostly of glass, mullite, quartz, and spines group minerals. Minor amounts of illite/muscovite, sulfates, hematite, and corundum are also present. Spinel group minerals identified include magnetite, franklinite, magnesioferrite, trevorite, jacobisite, and zincochromite. Scanning Electron Microscope analysis reveals that most of the spinel minerals are dendritic intergrowths within aluminum silicate glass. Unit I1 fly ash samples contain glass, quartz, perovskite, lime, gehlenite, and apatite with minor amounts of periclase, anhydrite

  13. Coal technologies of Japan in 1988 and 1989. 1988, 1989 nen no sekitan gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-25

    The 8th coal policy of Japan which has been in effect since 1987 has passed its half way and during the above period, coal mines such as Mitsubishi Takashima, Mitsui Sunagawa, Hokutan Horonai and Mitsubishi Minami-Ohyubari, etc. were closed and further concentration and rationalization of the production systems has been continued. Total coal production in FY 1988 as well as FY 1989 was 11.1 million tons and 9.7 million tons respectively, and concerning the development surveys of coal resources, maritime geophysical explorations and test drillings were done in Ariake Sea and off Kushiro, etc. and land geophysical explorations and test drillings at Asajino, etc.. International interchange concerning coal technologies was also very active and the amount of imported coal of various kinds exceeded that of the preceding fiscal year in both fiscal years, irrespective of the unconsumed year-end surplus coal storage in the domestic coal production. As shown above, domestic coal is inferior to overseas coal pricewise, hence domestic coal mines are pushing concentration of faces and introduction of larger coal mining machines. With regard to coal mine safety, the research and development of technologies of prediction and safety against gas issue, spontaneous combustion and mine fire, etc. is under way and coal processing technologies as well as coal utilization technologies such as fluidized bed incineration, etc. are now being developed. 3 figs., 12 tabs.

  14. Analysis of irrationality of coal susceptibility to spontaneous combustion determination method with fluid oxygen adsorption

    Institute of Scientific and Technical Information of China (English)

    HE Qi-lin

    2008-01-01

    Based on experiment results and theoretical analysis,pointed out that the method of coal susceptibility to spontaneous combustion determination with fluid oxygen adsorption can not present the essence of coal oxidation process and oxidation reaction.The method is incorrect,paying attention at one aspect and ignoring the rest.The method is not reasonable for coal susceptibility to spontaneous combustion determination.Susceptibility to spontaneous combustion of coal reflects chemical property of coal oxidation with oxygen absorption and heat release at low temperature.Coal's susceptibility to spontaneous combustion is mainly decided by the number of molecules with reaction activation energy and activation molecule production rate at certain temperature.Therefore,index of susceptibility to spontaneous combustion should adopt accumulative value or trend of heat release or oxygen adsorption during oxidation process.

  15. Analysis of irrationality of coal susceptibility to spontaneous combustion determination method with fluid oxygen adsorption

    Institute of Scientific and Technical Information of China (English)

    HE Qi-lin

    2008-01-01

    Based on experiment results and theoretical analysis, pointed out that the method of coal susceptibility to spontaneous combustion determination with fluid oxygen adsorption can not present the essence of coal oxidation process and oxidation reaction. The method is incorrect, paying attention at one aspect and ignoring the rest. The method is not reasonable for coal susceptibility to spontaneous combustion determination. Sus-ceptibility to spontaneous combustion of coal reflects chemical property of coal oxidation with oxygen absorption and heat release at low temperature. Coal's susceptibility to spon-taneous combustion is mainly decided by the number of molecules with reaction activation energy and activation molecule production rate at certain temperature. Therefore, index of susceptibility to spontaneous combustion should adopt accumulative value or trend of heat release or oxygen adsorption during oxidation process.

  16. Analysis of some potential social effects of four coal technologies

    Energy Technology Data Exchange (ETDEWEB)

    Walker, C.A.; Gould, L.C.

    1980-09-01

    This is an analysis of the potential social impacts of four coal technologies: conventional combustion, fluidized-bed combustion, liquifaction, and gasification. Because of their flexibility, and the abundance and relatively low costs of coal, the potential benefits of these technologies would seem to outweigh their potential social costs, both in the intermediate and long term. Nevertheless, the social costs of a coal industry are far more obscure and hard to quantify than the benefits. In general, however, it maybe expected that those technologies that can be deployed most quickly, that provide fuels that can substitute most easily for oil and natural gas, that are the cheapest, and that are the most thermally efficient will minimize social costs most in the intermediate term, while technologies that can guide energy infrastructure changes to become the most compatable with the fuels that will be most easily derived from inexhaustible sources (electricity and hydrogen) will minimize social costs most in the long run. An industry structured to favor eastern over western coal and plant sites in moderate sized communities, which could easily adapt to inexhaustible energy technologies (nuclear or solar) in the future, would be favored in either time period.

  17. Characterization of Oxy-combustion Impacts in Existing Coal-fired Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Bradley [Univ. of Utah, Salt Lake City, UT (United States); Davis, Kevin [Univ. of Utah, Salt Lake City, UT (United States); Senior, Constance [Univ. of Utah, Salt Lake City, UT (United States); Shim, Hong Shim [Univ. of Utah, Salt Lake City, UT (United States); Otten, Brydger Van [Univ. of Utah, Salt Lake City, UT (United States); Fry, Andrew [Univ. of Utah, Salt Lake City, UT (United States); Wendt, Jost [Univ. of Utah, Salt Lake City, UT (United States); Eddings, Eric [Univ. of Utah, Salt Lake City, UT (United States); Paschedag, Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Shaddix, Christopher [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cox, William [Brigham Young Univ., Provo, UT (United States); Tree, Dale [Brigham Young Univ., Provo, UT (United States)

    2013-09-30

    ) Assessment of oxy-combustion impacts in two full-scale coal-fired utility boiler retrofits based on computational fluid dynamics (CFD) modeling of air-fired and oxygen-fired operation. This research determined that it is technically feasible to retrofit the combustion system in an air-fired boiler for oxy-fired operation. The impacts of CO{sub 2} flue gas recycle and burner design on flame characteristics (burnout, NO{sub x}, SO{sub x}, mercury and fine particle emissions, heat transfer) and operational concerns (fouling, slagging and corrosion) were minimal, with the exception of high sulfur levels resulting from untreated flue gas recycle with medium and high-sulfur coals. This work focused on combustion in the radiant and convective sections of the boiler and did not address boiler system integration issues, plant efficiencies, impacts on downstream air pollution control devices, or CO{sub 2} capture and compression. The experimental data, oxy-firing system principles and oxy-combustion process mechanisms provided by this work can be used by electric utilities, boiler OEMs, equipment suppliers, design firms, software vendors, consultants and government agencies to assess retrofit applications of oxy-combustion technologies to existing boilers and to guide development of new designs.

  18. The effect of biomass on pollutant emission and burnout in co-combustion with coal

    Energy Technology Data Exchange (ETDEWEB)

    Kruczek, H.; Raczka, P.; Tatarek, A. [Wroclaw Technical University, Wroclaw (Poland)

    2006-08-15

    This paper presents experimental and numerical results on the co-combustion of different types of biomass with hard and brown coal. The main aim of this work was to assess the impact of the cocombustion of biomass in brown and hard coal-fired systems on the combustion process itself and on the level of pollutant formation and its dependence on combustion temperature stoichiometry. The experimental results obtained have shown that in general biomass addition leads to decreased NO and SO{sub 2} emissions, except with the hard coal Bogdanka. In addition, the biomass has a beneficial effect on the burnout of the coal/biomass mixture. To help to account for this effect, the behaviour of coal and biomass, the coal/biomass mixture and of fuel-N was studied by thermal analysis, in nitrogen and in air. The results obtained have shown that gas phase interactions are dominant in the combustion of biomass/coal mixtures.

  19. On-Line Analysis and Kinetic Behavior of Arsenic Release during Coal Combustion and Pyrolysis.

    Science.gov (United States)

    Shen, Fenghua; Liu, Jing; Zhang, Zhen; Dai, Jinxin

    2015-11-17

    The kinetic behavior of arsenic (As) release during coal combustion and pyrolysis in a fluidized bed was investigated by applying an on-line analysis system of trace elements in flue gas. This system, based on inductively coupled plasma optical emission spectroscopy (ICP-OES), was developed to measure trace elements concentrations in flue gas quantitatively and continuously. Obvious variations of arsenic concentration in flue gas were observed during coal combustion and pyrolysis, indicating strong influences of atmosphere and temperature on arsenic release behavior. Kinetic laws governing the arsenic release during coal combustion and pyrolysis were determined based on the results of instantaneous arsenic concentration in flue gas. A second-order kinetic law was determined for arsenic release during coal combustion, and the arsenic release during coal pyrolysis followed a fourth-order kinetic law. The results showed that the arsenic release rate during coal pyrolysis was faster than that during coal combustion. Thermodynamic calculations were carried out to identify the forms of arsenic in vapor and solid phases during coal combustion and pyrolysis, respectively. Ca3(AsO4)2 and Ca(AsO2)2 are the possible species resulting from As-Ca interaction during coal combustion. Ca(AsO2)2 is the most probable species during coal pyrolysis.

  20. Trace element emissions when firing pulverized coal in a pilot-scale combustion facility

    Energy Technology Data Exchange (ETDEWEB)

    Miller, S.F.; Wincek, R.T.; Miller, B.G.; Scaroni, A.W. [Pennsylvania State Univ., University Park, PA (United States)

    1998-04-01

    Title Ed of the Clean Air Act Amendments of 1990 designates 189 hazardous air pollutants (HAPs). Fourteen of the 189 substances identified are: antimony (Sb), beryllium (Be), chlorine (0), cobalt (Co), manganese (Mn), nickel (Ni), selenium (Se), fluorine (F), arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), and phosphorous (P). Eleven of these elements have been detected in the flue gas of pulverized coal-fired utility boilers. Currently there are no regulations that limit the emissions of these elements during coal combustion in utility- or industrial-scale boilers. Given the growing body of risk assessment data on these elements and their impact on the environment and human health, it is possible that regulations on emission levels for certain elements will be imposed. A knowledge of the occurrence of trace elements in coal and their behavior during combustion is essential to predict emissions and to develop control technologies for remediation. The partitioning of trace elements during combustion can be traced to their volatility within the system. For purposes of this paper, the classification of trace elements summarized by Clarke and Sloss will be used: Group I elements, i.e., elements that are not easily volatilized and form larger bottom ash and fly ash particles; Group H elements, i.e., elements that are partially or completely volatilization followed by condensation as small particles or on the surface of small particles; and Group III elements, i.e., elements that are readily volatilized and usually remain in the gas phase system.

  1. Performance Analysis of a Coal-Fired External Combustion Compressed Air Energy Storage System

    Directory of Open Access Journals (Sweden)

    Wenyi Liu

    2014-11-01

    Full Text Available Compressed air energy storage (CAES is one of the large-scale energy storage technologies utilized to provide effective power peak load shaving. In this paper, a coal-fired external combustion CAES, which only uses coal as fuel, is proposed. Unlike the traditional CAES, the combustion chamber is substituted with an external combustion heater in which high-pressure air is heated before entering turbines to expand in the proposed system. A thermodynamic analysis of the proposed CAES is conducted on the basis of the process simulation. The overall efficiency and the efficiency of electricity storage are 48.37% and 81.50%, respectively. Furthermore, the exergy analysis is then derived and forecasted, and the exergy efficiency of the proposed system is 47.22%. The results show that the proposed CAES has more performance advantages than Huntorf CAES (the first CAES plant in the world. Techno-economic analysis of the coal-fired CAES shows that the cost of electricity (COE is $106.33/MWh, which is relatively high in the rapidly developing power market. However, CAES will be more likely to be competitive if the power grid is improved and suitable geographical conditions for storage caverns are satisfied. This research provides a new approach for developing CAES in China.

  2. Kinetics of coal combustion: Part 3, Mechanisms and kinetics of char combustion

    Energy Technology Data Exchange (ETDEWEB)

    Gavalas, G. R.; Flagan, R. C. [California Inst. of Tech., Pasadena, CA (USA)

    1988-09-01

    This report summarizes a three-year research program aimed at developing this level of understanding of char combustion through a combination of detailed analysis of chars as produced during devolatilization and as they evolve during oxidation, and theoretical studies of the porous microstructures and of pore diffusion and reaction within the coal particles. A small number of coals have been studied in detail, namely a HVA bituminous (PSOC 1451), a sub-bituminous (PSOC 1488), and a lignite (PSOC 1443). Chars have been generated from size-classified samples of these coals by pyrolysis in an inert atmosphere in a drop tube furnace. The chars were then characterized both chemically and physically. Subsequent oxidation studies were performed on these chars. 42 refs., 54 figs., 4 tabs.

  3. Evaluating the thermal stability of mercury and other metals in coal combustion residues used in the production of cement clinker, asphalt, and wallboard

    Science.gov (United States)

    Research is underway by the U.S. Environmental Protection Agency (EPA) to document any changes that may occur to coal combustion residues (CCRs) as a result of implementation of mercury and multiipollutant control technology at coal-fired power plants. This work was cited as a pr...

  4. Coal combustion science: Task 1, Coal char combustion: Task 2, Fate of mineral matter. Quarterly progress report, July--September 1993

    Energy Technology Data Exchange (ETDEWEB)

    Hardesty, D.R. [ed.; Hurt, R.H.; Davis, K.A.; Baxter, L.L.

    1994-07-01

    Progress reports are presented for the following tasks: (1) kinetics and mechanisms of pulverized coal char combustion and (2) fate of inorganic material during coal combustion. The objective of Task 1 is to characterize the combustion behavior of selected US coals under conditions relevant to industrial pulverized coal-fired furnaces. In Sandia`s Coal Combustion Laboratory (CCL), optical techniques are used to obtain high-resolution images of individual burning coal char particles and to measure, in situ, their temperatures, sizes, and velocities. Detailed models of combustion transport processes are then used to determine kinetic parameters describing the combustion behavior as a function of coal type and combustion environment. Partially reacted char particles are also sampled and characterized with advanced materials diagnostics to understand the critical physical and chemical transformations that influence reaction rates and burnout times. The ultimate goal of the task is the establishment of a data base of the high temperature reactivities of chars from strategic US coals, from which important trends may be identified and predictive capabilities developed. The overall objectives for task 2 are: (1) to complete experimental and theoretical investigation of ash release mechanisms; (2) to complete experimental work on char fragmentation; (3) to establish the extent of coal (as opposed to char) fragmentation as a function of coal type and particle size; (4) to develop diagnostic capabilities for in situ, real-time, qualitative indications of surface species composition during ash deposition, with work continuing into FY94; (5) to develop diagnostic capabilities for in situ, real-time qualitative detection of inorganic vapor concentrations; and (6) to conduct a literature survey on the current state of understanding of ash deposition, with work continuing into FY94.

  5. Metallic species derived from fluidized bed coal combustion. [59 references

    Energy Technology Data Exchange (ETDEWEB)

    Natusch, D.F.S.; Taylor, D.R.

    1980-01-01

    Samples of fly ash generated by the combustion of Montana Rosebud coal in an experimental 18 inch fluidized bed combustor were collected. The use of a heated cascade impactor permitted collection of size fractionated material that avoided condensation of volatile gases on the particles. Elemental concentration trends were determined as a function of size and temperature and the results compared to published reports for conventional power plants. The behavior of trace metals appears to be substantially different in the two systems due to lower operating temperatures and the addition of limestone to the fluidized bed. Corrosion of the impactor plates was observed at the highest temperature and lowest limestone feed rate sampled during the study. Data from the elemental concentration and leaching studies suggest that corrosion is most likely due to reactions involving sodium sulfate. However, it is concluded that corrosion is less of a potential problem in fluidized-bed systems than in conventional coal-fired systems.

  6. A new SOx simulation model of coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Li Yonghua; Chen Hongwei; Zhen Zhi; Feng Zhaoxing; Dong Jianxun [North China Electric Power University, Baoding (China)

    2003-07-01

    It is very important to study the emission of pollutants from a coal combustion device, and we consider the best way is to use numerical simulation for such a study. By using a mathematical model with a post-processing method and based on combustion simulation, this paper reports the calculation of the SOx distribution in a power plant boiler furnace. For the formation of SOx, a conventional chemical reaction model is adopted, and according to the principles of reaction dynamics, a model for the SOx formation is also put forward. It is the first time the calculation and on-site testing an 800MW-unit boiler have been combined in China. The test and calculation results show that the model is reasonable, and such a study will be valuable as a reference for boiler design and clean operation. 5 refs., 1 fig., 3 tabs.

  7. 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.

  8. Co-combustion: A summary of technology

    Directory of Open Access Journals (Sweden)

    Leckner Bo

    2007-01-01

    Full Text Available Co-combustion of biomass or waste together with a base fuel in a boiler is a simple and economically suitable way to replace fossil fuels by biomass and to utilize waste. Co-combustion in a high-efficiency power station means utilization of biomass and waste with a higher thermal efficiency than what otherwise had been possible. Due to transport limitations, the additional fuel will only supply a minor part (less than a few hundreds MW fuel of the energy in a plant. There are several options: co-combustion with coal in pulverized or fluidized bed boilers, combustion on added grates inserted in pulverized coal boilers, combustors for added fuel coupled in parallel to the steam circuit of a power plant, external gas producers delivering its gas to replace an oil, gas or pulverized fuel burner. Furthermore biomass can be used for reburning in order to reduce NO emissions or for afterburning to reduce N2O emissions in fluidized bed boilers. Combination of fuels can give rise to positive or negative synergy effects, of which the best known are the interactions between S, Cl, K, Al, and Si that may give rise to or prevent deposits on tubes or on catalyst surfaces, or that may have an influence on the formation of dioxins. With better knowledge of these effects the positive ones can be utilized and the negative ones can be avoided.

  9. Co-combustion - a summary of technology

    Energy Technology Data Exchange (ETDEWEB)

    Bo Leckner [Chalmers University of Technology, Goeteborg (Sweden). Dept. of Energy and Environment

    2007-07-01

    Co-combustion of biomass or waste together with a base fuel in a boiler is a simple and economically suitable way to replace fossil fuels by biomass and to utilise waste. Co-combustion in a high-efficiency power station means utilisation of biomass and waste with a higher thermal efficiency than what otherwise had been possible. Due to transport limitations, the additional fuel will only supply a minor part (less than a few hundreds MW{sub fuel}) of the energy in a plant. There are several options: co-combustion with coal in pulverised or fluidised bed boilers, combustion on added grates inserted in pulverised coal boilers, combustors for added fuel coupled in parallel to the steam circuit of a power plant, external gas producers delivering its gas to replace an oil, gas or pulverised fuel burner. Furthermore biomass can be used for reburning in order to reduce NO emissions or for afterburning to reduce N{sub 2}O emissions in fluidised bed boilers. Combination of fuels can give rise to positive or negative synergy effects, of which the best known are the interactions between S, Cl, K, Al, and Si that may give rise to or prevent deposits on tubes or on catalyst surfaces, or that may have an influence on the formation of dioxins. With better knowledge of these effects the positive ones can be utilised and the negative ones can be avoided. 71 refs., 19 figs., 5 tabs.

  10. Pyrolysis of Compositions of Mixtures of Combustible Shales and Brown Coals Deposited in Belarus

    Science.gov (United States)

    Lishtvan, I. I.; Dudarchik, V. M.; Kraiko, V. M.; Belova, Yu. V.

    2013-11-01

    This paper presents the results of investigating the pyrolysis of compositions of mixtures of brown coals and combustible shales in a close-packed and a moving layer and the yield dynamics of the pyrolysis gas and resin. A comparative analysis of the quality of pyrolysis products obtained from combustible shales and brown coal and from their mixtures has been performed.

  11. Soot, organics, and ultrafine ash from air- and oxy-fired coal combustion

    Science.gov (United States)

    This paper/presentation is concerned with determining the effects of oxy-combustion of coal on the composition of the ultrafine fly ash. To this end, a 10 W externally heated entrained flow furnace was modified to allow the combustion of pulverized coal in flames under practicall...

  12. Soot, organics and ultrafine ash from air- and oxy-fired coal combustion

    Science.gov (United States)

    This paper is concerned with determining the effects of oxy-combustion of coal on the composition of the ultrafine fly ash. To this end, a 10 W externally heated entrained flow furnace was modified to allow the combustion of pulverized coal in flames under practically relevant s...

  13. Environmental indicators of the combustion of prospective coal water slurry containing petrochemicals.

    Science.gov (United States)

    Dmitrienko, Margarita A; Nyashina, Galina S; Strizhak, Pavel A

    2017-09-15

    Negative environmental impact of coal combustion has been known to humankind for a fairly long time. Sulfur and nitrogen oxides are considered the most dangerous anthropogenic emissions. A possible solution to this problem is replacing coal dust combustion with that of coal water slurry containing petrochemicals (CWSP). Coal processing wastes and used combustible liquids (oils, sludge, resins) are promising in terms of their economic and energy yield characteristics. However, no research has yet been conducted on the environmental indicators of fuels based on CWSP. The present work contains the findings of the research of CO, CO2, NOx, SOx emissions from the combustion of coals and CWSPs produced from coal processing waste (filter cakes). It is demonstrated for the first time that the concentrations of dangerous emissions from the combustion of CWSPs (carbon oxide and dioxide), even when combustible heavy liquid fractions are added, are not worse than those of coal. As for the concentration of sulfur and nitrogen oxides, it is significantly lower for CWSPs combustion as compared to coals. The presented research findings illustrate the prospects of the wide use of CWSPs as a fuel that is cheap and beneficial, in terms of both energy output and ecology, as compared to coal. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Dynamic mathematical model and numerical calculation method on spontaneous combustion of loose coal

    Institute of Scientific and Technical Information of China (English)

    WEN Hu(文虎)

    2003-01-01

    Through the experiment of coal spontaneous combustion and relationship particle size with oxidation character of loose coal, some calculation formula of characteristic parameters is got in the process of coal spontaneous combustion. According to these theories of porous medium hydrodynamics, mass transfer and heat transfer, mathematical models of air leak field, oxygen concentration field and temperature field are set up. Through experimental and theoretical analysis, 3-D dynamic mathematical model of coal spontaneous combustion is set up. The method of ascertaining boundary condition of model is analyzed, and finite difference method is adopted to solve 2-D mathematical model.

  15. Simulation on Different Proportions of Coal and Natural Gas Co-combustion in a Rotary Lime Kiln

    Directory of Open Access Journals (Sweden)

    Hongyu Gu

    2011-06-01

    Full Text Available Co-combustion of coal and natural gas is a promising technology in the production of active lime. For this technology, proper fuel proportion of coal and natural gas (α is one of the key parameters that requires significant thought. By means of numerical simulation, contrast studies on co-combustion with five different fuel proportions were carried out. This paper firstly puts forward the models used to describe the system based on the actual conditions. Then, numerical simulation results were analysed in detail to illustrate the co-combustion process and the velocity and temperature distribution in the kiln. Finally, comparisons of high temperature region, char conversion, length of calcining zone, CO and NOx emission and total heat transfer rate to the material bed were made in order to make a decision on fuel proportion. Synthetically considering, α=30% is a balance between benefits and costs for the rotary lime kiln studied.

  16. Formation of fine particles in co-combustion of coal and solid recovered fuel in a pulverized coal-fired power station

    DEFF Research Database (Denmark)

    Wu, Hao; Pedersen, Anne Juul; Glarborg, Peter

    2011-01-01

    Fine particles formed from combustion of a bituminous coal and co-combustion of coal with 7 th% (thermal percentage) solid recovered fuel (SRF) in a pulverized coal-fired power plant were sampled and characterized in this study. The particles from dedicated coal combustion and co-combustion both...... appear to be an important formation mechanism. The elemental composition of the particles from coal combustion showed that S and Ca were significantly enriched in ultrafine particles and P was also enriched considerably. However, compared with supermicron particles, the contents of Al, Si and K were...

  17. Clean Coal Technology Programs: Program Update 2009

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-10-01

    The purpose of the Clean Coal Technology Programs: Program Update 2009 is to provide an updated status of the U.S. Department of Energy (DOE) commercial-scale demonstrations of clean coal technologies (CCT). These demonstrations have been performed under the Clean Coal Technology Demonstration Program (CCTDP), the Power Plant Improvement Initiative (PPII), and the Clean Coal Power Initiative (CCPI). Program Update 2009 provides: (1) a discussion of the role of clean coal technology demonstrations in improving the nation’s energy security and reliability, while protecting the environment using the nation’s most abundant energy resource—coal; (2) a summary of the funding and costs of the demonstrations; and (3) an overview of the technologies being demonstrated, along with fact sheets for projects that are active, recently completed, or recently discontinued.

  18. Co-combustion of different sewage sludge and coal: a non-isothermal thermogravimetric kinetic analysis.

    Science.gov (United States)

    Otero, M; Calvo, L F; Gil, M V; García, A I; Morán, A

    2008-09-01

    The kinetics of the combustion of coal, two different sewage sludge and their blends (containing different dried weight percentages of sewage sludge) was studied by simultaneous thermogravimetric analysis. Once the weight percentage of sludge in the blend was 10%, the effects on the combustion of coal were hardly noticeable in terms of weight loss. The Arrhenius activation energy corresponding to the co-combustion of the blends was evaluated by non-isothermal kinetic analysis. This showed that, though differences between coal and sewage sludge, the combustion of their blends kept kinetically alike to that of the coal. This work illustrates how thermogravimetric analysis may be used as an easy rapid tool to asses, not only mass loss, but also kinetics of the co-combustion of sewage sludge and coal blends.

  19. Mercury emission, control and measurement from coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Wei-Ping [North China Electric Power Univ., Beijing (China). School of Energy and Power Engineering; Western Kentucky Univ., Bowling Green, KY (United States). Inst. for Combustion Science and Environmental Technology; Cao, Yan [Western Kentucky Univ., Bowling Green, KY (United States). Inst. for Combustion Science and Environmental Technology; Zhang, Kai [North China Electric Power Univ., Beijing (China). School of Energy and Power Engineering

    2013-07-01

    Coal-fired electric power generation accounts for 65% of U.S. emissions of sulfur dioxide (SO2), 22% of nitrogen oxides (NOx), and 37% of mercury (Hg). The proposed Clear Air Interstate Rule (CAIR) and Clean Air Mercury Rule (CAMR) will attempt to regulate these emissions using a cap-and-trade program to replace a number of existing regulatory requirements that will impact this industry over the next decade. Mercury emissions remain the largest source that has not yet been efficiently controlled, in part because this is one of the most expensive to control. Mercury is a toxic, persistent pollutant that accumulates in the food chain. During the coal combustion process, when both sampling and accurate measurements are challenging, we know that mercury is present in three species: elemental, oxidized and particulate. There are three basic types of mercury measurement methods: Ontario Hydro Method, mercury continuous emission monitoring systems (CEMS) and sorbent-based monitoring. Particulate mercury is best captured by electrostatic precipitators (ESP). Oxidized mercury is best captured in wet scrubbers. Elemental mercury is the most difficult to capture, but selective catalytic reduction units (SCRs) are able to convert elemental mercury to oxidized mercury allowing it to be captured by wet flue gas desulfurization (FGD). This works well for eastern coals with high chlorine contents, but this does not work well on the Wyoming Powder River Basin (PRB) coals. However, no good explanation for its mechanism, correlations of chlorine content in coal with SCR performance, and impacts of higher chlorine content in coal on FGD re-emission are available. The combination of SCR and FGD affords more than an 80% reduction in mercury emissions in the case of high chlorine content coals. The mercury emission results from different coal ranks, boilers, and the air pollution control device (APCD) in power plant will be discussed. Based on this UAEPA new regulation, most power plants

  20. Co-combustion of waste from olive oil production with coal in a fluidised bed.

    Science.gov (United States)

    Cliffe, K R; Patumsawad, S

    2001-01-01

    Waste from olive oil production was co-fired with coal in a fluidised bed combustor to study the feasibility of using this waste as an energy source. The combustion efficiency and CO emission were investigated and compared to those of burning 100% of coal. Olive oil waste with up to 20% mass concentration can be co-fired with coal in a fluidised bed combustor designed for coal combustion with a maximum drop of efficiency of 5%. A 10% olive oil waste concentration gave a lower CO emission than 100% coal firing due to improved combustion in the freeboard region. A 20% olive oil waste mixture gave a higher CO emission than both 100% coal firing and 10% olive oil waste mixture, but the combustion efficiency was higher than the 10% olive oil waste mixture due to lower elutriation from the bed.

  1. Evaluation of the propensity for coal spontaneous combustion based on catastrophe theory

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yu-tao; ZHANG Xi-chen; TIEN Jerry C; LI Ya-qing

    2011-01-01

    Generally,different prevention measures should be taken according to spontaneous combustion propensities.The current methods to evaluate the propensity of coal spontaneous combustion,such as chromatographic method of oxygen adsorption,oxidation kinetics method and activation energy method,are mostly affected by human factors.Their boundaries among different classes of propensities were all established by subjective judgments.A new evaluation method using catastrophe theory is introduced.This method can accurately depict the process of coal spontaneous combustion and the evaluation index,"catastrophe temperature",be obtained based on the model.In terms of catastrophe temperature,the spontaneous combustion propensity of different coals can be sequenced.Experimental data indicate that this method is appropriate to describe the spontaneous combustion process and to evaluate the propensity of coal spontaneous combustion.

  2. Investigation on thermal and trace element characteristics during co-combustion biomass with coal gangue.

    Science.gov (United States)

    Zhou, Chuncai; Liu, Guijian; Fang, Ting; Lam, Paul Kwan Sing

    2015-01-01

    The thermochemical behaviors during co-combustion of coal gangue (CG), soybean stalk (SS), sawdust (SD) and their blends prepared at different ratios have been determined via thermogravimetric analysis. The simulate experiments in a fixed bed reactor were performed to investigate the partition behaviors of trace elements during co-combustion. The combustion profiles of biomass was more complicated than that of coal gangue. Ignition property and thermal reactivity of coal gangue could be enhanced by the addition of biomass. No interactions were observed between coal gangue and biomass during co-combustion. The volatilization ratios of trace elements decrease with the increasing proportions of biomass in the blends during co-combustion. Based on the results of heating value, activation energy, base/acid ratio and gaseous pollutant emissions, the blending ratio of 20-30% biomass content is regarded as optimum composition for blending and could be applied directly at current combustion application with few modifications.

  3. Fluorine emission from com-bustion of steam coal of North China Plate and Northwest China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    To study the amount of fluorine emission from the combustion of the steam coal (mainly Permo-Carbonif- erous coal) from the North China Plate and Northwest China, the fluorine contents of the coal, the fly ash and the cinder in high-temperature power stations as well as mid-low temperature power stations have been analyzed. This note provides a rough estimate of the total annual amount of fluorine emission as well as emission ratio from steam coal combustion in China. Our results show that by combustion of 1 t of Permo-Carboniferous coal (containing roughly 100 g fluorine), high-temperature power stations emit roughly 90 g fluorine into the atmosphere. The fluorine emission ratio of coal combustion in high-temperature power stations is about 96% and that in mid-low temperature power stations is about 78%. A total of 800 million tons of coal is burnt in China every year, and the coal comes mainly from Permo- Carboniferous deposite in the North China Plate and Northwest China coal mines. Taking the average fluorine content of the coal used at a low value of 100 mg/kg, the total annual fluorine emission from steam coal combustion into the atmosphere is estimated to be 66398 t.

  4. [Emission factors of polycyclic aromatic hydrocarbons (PAHs) in residential coal combustion and its influence factors].

    Science.gov (United States)

    Hai, Ting-Ting; Chen, Ying-Jun; Wang, Yan; Tian, Chong-Guo; Lin, Tian

    2013-07-01

    As the emission source of polycyclic aromatic hydrocarbons (PAHs), domestic coal combustion has attracted increasing attention in China. According to the coal maturity, combustion form and stove type associated with domestic coal combustion, a large-size, full-flow dilution tunnel and fractional sampling system was employed to collect the emissions from five coals with various maturities, which were burned in the form of raw-coal-chunk (RCC)/honeycomb-coal-briquettes (HCB) in different residential stoves, and then the emission factors of PAHs (EF(PAHs)) were achieved. The results indicate that the EF(PAHs) of bituminous coal ranged from 1.1 mg x kg(-1) to 3.9 mg x kg(-1) for RCC and 2.5 mg x kg(-1) to 21. 1 mg x kg(-1) for HCB, and the anthracite EF(PAH8) were 0.2 mg x kg(-1) for RCC and 0.6 mg x kg(-1) for HCB, respectively. Among all the influence factors of emission factors of PAHs from domestic coal combustion, the maturity of coal played a major role, the range of variance reaching 1 to 2 orders of magnitude in coals with different maturity. Followed by the form of combustion (RCC/HCB), the EF(PAHs) of HCB was 2-6 times higher than that of RCC for the same geological maturity of the coal. The type of stove had little influence on EF(PAHs).

  5. Structure-Based Predictive model for Coal Char Combustion.

    Energy Technology Data Exchange (ETDEWEB)

    Hurt, R.; Colo, J [Brown Univ., Providence, RI (United States). Div. of Engineering; Essenhigh, R.; Hadad, C [Ohio State Univ., Columbus, OH (United States). Dept. of Chemistry; Stanley, E. [Boston Univ., MA (United States). Dept. of Physics

    1997-09-24

    During the third quarter of this project, progress was made on both major technical tasks. Progress was made in the chemistry department at OSU on the calculation of thermodynamic properties for a number of model organic compounds. Modelling work was carried out at Brown to adapt a thermodynamic model of carbonaceous mesophase formation, originally applied to pitch carbonization, to the prediction of coke texture in coal combustion. This latter work makes use of the FG-DVC model of coal pyrolysis developed by Advanced Fuel Research to specify the pool of aromatic clusters that participate in the order/disorder transition. This modelling approach shows promise for the mechanistic prediction of the rank dependence of char structure and will therefore be pursued further. Crystalline ordering phenomena were also observed in a model char prepared from phenol-formaldehyde carbonized at 900{degrees}C and 1300{degrees}C using high-resolution TEM fringe imaging. Dramatic changes occur in the structure between 900 and 1300{degrees}C, making this char a suitable candidate for upcoming in situ work on the hot stage TEM. Work also proceeded on molecular dynamics simulations at Boston University and on equipment modification and testing for the combustion experiments with widely varying flame types at Ohio State.

  6. The effect of fuel pyrolysis on the coal particle combustion: An analytical investigation

    OpenAIRE

    Baghsheikhi Mostafa; Rahbari Alireza; Ashrafizadeh Seyed Mehdi; Bidabadi Mehdi

    2016-01-01

    The aim of this work is to analytically investigate the symmetrical combustion of an isolated coal particle with the fuel pyrolysis effect. The modelling concept of coal particles is similar to that of the liquid droplet combustion but in the case of coal devolatilization, the particles do not shrink like droplet does due to evaporation of liquid fuel. The rate of devolatilization of volatiles can be calculated using the equation that is similar to Arrheniu...

  7. Coal combustion science quarterly progress report, October--December 1992. Task 1, Coal char combustion [and] Task 2, Fate of mineral matter

    Energy Technology Data Exchange (ETDEWEB)

    Hardesty, D.R. [ed.] [Sandia National Labs., Livermore, CA (United States); Hurt, R.H.; Baxter, L.L. [Sandia National Labs., Albuquerque, NM (United States)

    1993-06-01

    In the Coal Combustion Laboratory (CCL) this quarter, controlled laboratory experiments were carried out to better understand the late stages of coal combustion and its relation to unburned carbon levels in fly ash. Optical in situ measurements were made during char combustion at high carbon conversions and the optical data were related to particle morphologies revealed by optical microscopy on samples extracted under the same conditions. Results of this work are reported in detail below. In the data presented below, we compare the fraction of alkali metal loss to that of the alkaline earth metals as a function of coal rank to draw conclusions about the mechanism of release for the latter. Figure 2.1 illustrates the fractional release of the major alkali and alkaline earth metals (Na, K, Ca, Mg) as a function of coal rank for a series of coals and for several coal blends. All data are derived from combustion experiments in Sandia`s Multifuel Combustor (MFC) and represent the average of three to eight experiments under conditions where the mass loss on a dry, ash-free (daf) basis exceeds 95 %. There are no missing data in the figure. The several coals with no indicated result exhibited no mass loss of the alkali or alkaline earth metals in our experiments. There is a clear rank dependence indicated by the data in Fig. 2.1, reflecting the mode of occurrence of the material in the coal.

  8. Recent advances in the use of synchrotron radiation for the analysis of coal combustion products

    Energy Technology Data Exchange (ETDEWEB)

    Manowitz, B. [Brookhaven National Lab., Upton, NY (United States)

    1995-11-01

    Two major coal combustion problems are the formation and build-up of slag deposits on heat transfer surfaces and the production and control of toxic species in coal combustion emissions. The use of synchrotron radiation for the analysis of coal combustion products can play a role in the better understanding of both these phenomena. An understanding of the chemical composition of such slags under boiler operating conditions and as a function of the mineral composition of various coals is one ultimate goal of this program. The principal constituents in the ash of many coals are the oxides of Si, Al, Fe, Ca, K, S, and Na. The analytical method required must be able to determine the functional forms of all these elements both in coal and in coal ash at elevated temperatures. One unique way of conducting these analyses is by x-ray spectroscopy.

  9. Mercury speciation and emissions from coal combustion in Guiyang, Southwest China.

    Science.gov (United States)

    Tang, Shunlin; Feng, Xinbin; Qiu, Jianrong; Yin, Guoxun; Yang, Zaichan

    2007-10-01

    Although China has been regarded as one of the largest anthropogenic mercury emission source with coal combustion, so far the actual measurements of Hg species and Hg emissions from the combustion and the capture of Hg in Chinese emission control devices were very limited. Aiming at Hg mercury species measurements in Guiyang, the capital city of Guizhou province in Southwest China, we studied flue gases of medium-to-small-sized industrial steam coal-firing boiler (10-30 t/h) with no control devices, medium-to-small-sized industrial steam coal-firing boiler with WFGD and large-scale coal combustion with ESPs using Ontario Hytro method. We obtained mercury emission factors of the three representative coal combustion and estimated mercury emissions in Guiyang in 2003, as well as the whole province from 1986 to 2002. Coal combustion in Guiyang emitted 1898 kg mercury to the atmosphere, of which 36% Hg is released from power plants, 41% from industrial coal combustion, and 23% from domestic users, and 267 kg is Hg(p), 813 kg is Hg(2+) and 817 kg is Hg0. Mercury emission in Guizhou province increased sharply from 5.8 t in 1986 to 16.4 t in 2002. With the implementation of national economic strategy of China's Western Development, the annual mercury emission from coal combustion in the province is estimated to be about 32 t in 2015.

  10. Experiment study of optimization on prediction index gases of coal spontaneous combustion

    Institute of Scientific and Technical Information of China (English)

    牛会永; 邓湘陵; 李石林; 蔡康旭; 朱豪; 李芳; 邓军

    2016-01-01

    The coal of Anyuan Mine has the characteristic of easy spontaneous combustion. Conventional method is difficult to predict it. Coal samples from this mine were tested in laboratory. The data obtained from laboratory determination were initialized for the value which was defined as “K”. The ratio of each index gas and value of “K”, and the ratio of combination index gases and value of “K”, were analyzed simultaneously. The research results show that for this coal mine, if there is carbon monoxide in the gas sample, the phenomenon of oxidation and temperature rising for coal exists in this mine; if there is C2H4 in the gas sample, the temperature of coal perhaps exceeds 130 °C. If the coal temperature is between 35 °C and 130 °C, prediction and forecast for coal spontaneous combustion depend on the value ofΦ(CO)/K mainly; if the temperature of coal is between 130 °C and 300 °C, prediction and forecast for coal spontaneous combustion depend on the value ofΦ(C2H6)/Φ(C2H2)andΦ(C2H6)/K. The research results provide experimental basis for the prediction of coal spontaneous combustion in Anyuan coal mine, and have better guidance on safe production of this coal mine.

  11. Effect of biomass blending on coal ignition and burnout during oxy-fuel combustion

    Energy Technology Data Exchange (ETDEWEB)

    B. Arias; C. Pevida; F. Rubiera; J.J. Pis [Instituto Nacional del Carbon, CSIC, Oviedo (Spain)

    2008-09-15

    Oxy-fuel combustion is a GHG abatement technology in which coal is burned using a mixture of oxygen and recycled flue gas, to obtain a rich stream of CO{sub 2} ready for sequestration. An entrained flow reactor was used in this work to study the ignition and burnout of coals and blends with biomass under oxy-fuel conditions. Mixtures of CO{sub 2}/O{sub 2} of different concentrations were used and compared with air as reference. A worsening of the ignition temperature was detected in CO{sub 2}/O{sub 2} mixtures when the oxygen concentration was the same as that of the air. However, at an oxygen concentration of 30% or higher, an improvement in ignition was observed. The blending of biomass clearly improves the ignition properties of coal in air. The burnout of coals and blends with a mixture of 79%CO{sub 2}-21%O{sub 2} is lower than in air, but an improvement is achieved when the oxygen concentration is 30 or 35%. The results of this work indicate that coal burnout can be improved by blending biomass in CO{sub 2}/O{sub 2} mixtures. 26 refs., 7 figs., 1 tab.

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

    Science.gov (United States)

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

    2016-07-19

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

  13. STRUCTURE-BASED PREDICTIVE MODEL FOR COAL CHAR COMBUSTION

    Energy Technology Data Exchange (ETDEWEB)

    CHRISTOPHER M. HADAD; JOSEPH M. CALO; ROBERT H. ESSENHIGH; ROBERT H. HURT

    1998-06-04

    During the past quarter of this project, significant progress continued was made on both major technical tasks. Progress was made at OSU on advancing the application of computational chemistry to oxidative attack on model polyaromatic hydrocarbons (PAHs) and graphitic structures. This work is directed at the application of quantitative ab initio molecular orbital theory to address the decomposition products and mechanisms of coal char reactivity. Previously, it was shown that the �hybrid� B3LYP method can be used to provide quantitative information concerning the stability of the corresponding radicals that arise by hydrogen atom abstraction from monocyclic aromatic rings. In the most recent quarter, these approaches have been extended to larger carbocyclic ring systems, such as coronene, in order to compare the properties of a large carbonaceous PAH to that of the smaller, monocyclic aromatic systems. It was concluded that, at least for bond dissociation energy considerations, the properties of the large PAHs can be modeled reasonably well by smaller systems. In addition to the preceding work, investigations were initiated on the interaction of selected radicals in the �radical pool� with the different types of aromatic structures. In particular, the different pathways for addition vs. abstraction to benzene and furan by H and OH radicals were examined. Thus far, the addition channel appears to be significantly favored over abstraction on both kinetic and thermochemical grounds. Experimental work at Brown University in support of the development of predictive structural models of coal char combustion was focused on elucidating the role of coal mineral matter impurities on reactivity. An �inverse� approach was used where a carbon material was doped with coal mineral matter. The carbon material was derived from a high carbon content fly ash (Fly Ash 23 from the Salem Basin Power Plant. The ash was obtained from Pittsburgh #8 coal (PSOC 1451). Doped

  14. Reaction Kinetic Equation for Char Combustion of Underground Coal Gasification

    Institute of Scientific and Technical Information of China (English)

    YU Hong-guan; YANG Lan-he; FENG Wei-min; LIU Shu-qin; SONG Zhen-qi

    2006-01-01

    Based on the quasi-steady-state approximation, the dynamic equation of char combustion in the oxidation zone of underground coal gasification (UCG) was derived. The parameters of the dynamic equation were determined at 900℃ using a thermo-gravimetric (TG) analyzer connected to a flue gas analyzer and this equation. The equation was simplified for specific coals, including high ash content, low ash content, and low ash fusibility ones. The results show that 1) the apparent reaction rate constant increases with an increase in volatile matter value as dry ash-free basis, 2) the effective coefficient of diffusion decreases with an increase in ash as dry basis, and 3) the mass transfer coefficient is independent of coal quality on the whole. The apparent reaction rate constant, mass-transfer coefficient and effective coefficient of diffusion of six char samples range from 7.51×104 m/s to 8.98×104 m/s, 3.05×106 m/s to 3.23×106 m/s and 5.36×106 m2/s to 8.23×106 m2/s at 900℃, respectively.

  15. Combustion of coal residue in a fluidised bed Part II - experiment results. Combustion de residuos de carbon en lecho fluidizado parte II; resultados experimentales

    Energy Technology Data Exchange (ETDEWEB)

    Pis, J.J.; Fuertes, A.B.; Alvarez, F.J.; Jul, J.J.; Canibano, J.G. (Inst. Nacional del Carbon, Oviedo (Spain))

    1988-09-01

    A study is being carried out at the National Coal Institute on the fluidised bed combustion of fine tailings. The purpose of the study is to assess the possibilities for using this technology as a means for reducing the environmental impact of this type of material and for recovering its energy content. The article gives the results obtained in various experiments carried out with this type of residue. 9 refs., 6 figs., 2 tabs.

  16. 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.

  17. Prospects for coal and clean coal technologies in Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    Paul Baruya [IEA Clean Coal Centre, London (United Kingdom)

    2010-07-15

    Malaysia is a regular participant in world coal trade. Coal production is a modest 1 Mt/y but, as an importer, the country trades some 30 Mt/y. As one of ASEAN's most prosperous economies, the expected growth in electricity demand is inevitable. For many years the country has been dependent on gas-fired power, much of which is in the form of expensive single cycle gas turbines. However, coal-fired power has emerged as an important provider of power in a country desperate to improve its energy security. This report looks at how coal-fired power has developed, and examines the current technologies deployed in the country. It is the fourth in a series of reports by the lEA Clean Coal Centre on ASEAN countries, following Indonesia, Thailand and Vietnam. 35 refs., 14 figs., 4 tabs.

  18. Possibility of Reducing Formations of NOx and SO2 Simultaneously during Coal Combustion

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Comparing with other NOx and SO2 control technologies, in-bed reducing NOx and SO2 simultaneously during coal combustion may lower the investment and operation cost. However, there are several possible contradictions between the reduction of NOx and the capture of SO2 during combustion: 1) CO rich atmosphere is favorable for the reduction of NOx, whereas O2 rich favorable for the capture of SO2; 2) higher preheating temperature of coal is favorable for reducing NOx, but unfavorable for reducing SO2; 3) sulphation of some minerals may deactivate their catalytic effect on the reduction of NOx. The attempts to eliminate such contradictions by coating coal granules with thin layer of monometallic oxides and mixed oxides were proposed. Ni2O3 and Fe2O3 showed high activity on NOx reduction and CaO and Cr2O3 showed good effect on sulfur capture. The mixed metallic oxides, e.g., Fe2O3NiO, etc., showed effective for both NOx reduction and SO2 retention. It is possible to in-bed reduce NOx and SO2 simultaneously if the adhering materials are properly chosen to be difunctional materials of both active catalysts for NOx reduction reactions and better sorbents for SO2 retention.

  19. Comparison of an Internal Combustion Engine Derating Operated on Producer Gas from Coal and Biomass Gasification

    Directory of Open Access Journals (Sweden)

    Muhammad Ade Andriansyah Efendi

    2016-06-01

    Full Text Available Gasification is an effective and clean way to convert coal and biomass into useful fuels and chemical feedstocks. Producer gas utilization for internal combustion engine has been studied, not only from biomass gasification but also from coal gasification. This paper compares the research that has done author using coal gasification with other research results using biomass gasification. Coal gasifier performance test conducted with capacity of 20 kg/h coal. The proximate and ultimate analysis of raw coal, ash product and producer gas was conducted and comparised. The result of analysis shows that the efficiency of the coal gasification was 61% while range of gasifier efficiency for biomass is between 50-80%. Meanwhile, the experimental results on the performance of internal combustion engines using gas producer shows that the derating for power generation using coal producer gas was 46% and biomass was 20-50% depend on compression ratio of engine and characteristic of producer gas. 

  20. Naturally Occurring Radioactive Materials in Coals and Coal Combustion Residuals in the United States.

    Science.gov (United States)

    Lauer, Nancy E; Hower, James C; Hsu-Kim, Heileen; Taggart, Ross K; Vengosh, Avner

    2015-09-15

    The distribution and enrichment of naturally occurring radioactive materials (NORM) in coal combustion residuals (CCRs) from different coal source basins have not been fully characterized in the United States. Here we provide a systematic analysis of the occurrence of NORM ((232)Th, (228)Ra, (238)U, (226)Ra, and (210)Pb) in coals and associated CCRs from the Illinois, Appalachian, and Powder River Basins. Illinois CCRs had the highest total Ra ((228)Ra + (226)Ra = 297 ± 46 Bq/kg) and the lowest (228)Ra/(226)Ra activity ratio (0.31 ± 0.09), followed by Appalachian CCRs (283 ± 34 Bq/kg; 0.67 ± 0.09), and Powder River CCRs (213 ± 21 Bq/kg; 0.79 ± 0.10). Total Ra and (228)Ra/(226)Ra variations in CCRs correspond to the U and Th concentrations and ash contents of their feed coals, and we show that these relationships can be used to predict total NORM concentrations in CCRs. We observed differential NORM volatility during combustion that results in (210)Pb enrichment and (210)Pb/(226)Ra ratios greater than 1 in most fly-ash samples. Overall, total NORM activities in CCRs are 7-10- and 3-5-fold higher than NORM activities in parent coals and average U.S. soil, respectively. This study lays the groundwork for future research related to the environmental and human health implications of CCR disposal and accidental release to the environment in the context of this elevated radioactivity.

  1. ABB Combustion Engineering nuclear technology

    Energy Technology Data Exchange (ETDEWEB)

    Matzie, R.A.

    1994-12-31

    The activities of ABB Combustion Engineering in the design and construction of nuclear systems and components are briefly reviewed. ABB Construction Engineering continues to improve the design and design process for nuclear generating stations. Potential improvements are evaluated to meet new requirements both of the public and the regulator, so that the designs meet the highest standards worldwide. Advancements necessary to meet market needs and to ensure the highest level of performance in the future will be made.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-07-01

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

  3. Effects of Coal Combustion Additives on the Forms and Recovery of Uranium in Coal Bottom Ash

    Science.gov (United States)

    Tang, Ye; Li, Yilian

    2017-04-01

    Recovering uranium from uranium-rich coal ash is an important way to utilize unconventional uranium resource. Although it might be expected that the uranium in residual form would prevent uranium recovery from coal ash, raising the recovery rate in way of controlling residual uranium has not yet been studied. In this study, three different kinds of combustion promoting additives were investigated by coal combustion experiments, in order to decrease the proportion of residual-form uranium in ash and increase the acid leaching rate. Analytical procedures included Tessier sequential extraction, acidleaching, and characterization(ICP-MS, XRF, BET and SEM-EDS). It was showed that the effects of additives in reducing residual uranium were as the following order: alkaline earth metal compounds > transition metal compounds> alkali metal compounds. Adding alkali metal additives(KCl, NaCl, K2CO3, Na2CO3) raised the percentage of residual uranium largely. Additionally, one transition metal additive(Fe2O3) reached a decreasing amplitude of 5.15%, while the other two additives(MnO2 and Fe3O4)made the rates increased. However, coal combustion with alkaline earth metal compounds mixed had target effects. Among this kind of additives(Ca(OH)2, CaCO3, CaO, CaCl2), CaCO3displayed the best effect on restricting the rising proportion of residual uranium by 18%. Moreover, the leaching recovery research indicated that CaCO3 could raise the recovery rate by 10.8%. The XRF profiles supported that the CaCO3 could lower the concentration of SiO2 in the bottom ash from 79.76% to 49.69%. Besides, The BET and SEM revealed that the decomposition of CaCO3 brought about a variation of surface structures and area, which promoted the contact between the leaching agent and bottom ash. The uranium content increase was determined by ICP-MS and EDS. These findings suggest that CaCO3 could be a favorable additive for the controlling of residual uranium and improvement of uranium recovery rates. Key words

  4. Sustainable development with clean coal

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-08-01

    This paper discusses the opportunities available with clean coal technologies. Applications include new power plants, retrofitting and repowering of existing power plants, steelmaking, cement making, paper manufacturing, cogeneration facilities, and district heating plants. An appendix describes the clean coal technologies. These include coal preparation (physical cleaning, low-rank upgrading, bituminous coal preparation); combustion technologies (fluidized-bed combustion and NOx control); post-combustion cleaning (particulate control, sulfur dioxide control, nitrogen oxide control); and conversion with the integrated gasification combined cycle.

  5. Next Generation Pressurized Oxy-Coal Combustion: High Efficiency and No Flue Gas Recirculation

    Energy Technology Data Exchange (ETDEWEB)

    Rue, David

    2013-09-30

    The Gas Technology Institute (GTI) has developed a pressurized oxy-coal fired molten bed boiler (MBB) concept, in which coal and oxygen are fired directly into a bed of molten coal slag through burners located on the bottom of the boiler and fired upward. Circulation of heat by the molten slag eliminates the need for a flue gas recirculation loop and provides excellent heat transfer to steam tubes in the boiler walls. Advantages of the MBB technology over other boilers include higher efficiency (from eliminating flue gas recirculation), a smaller and less expensive boiler, modular design leading to direct scalability, decreased fines carryover and handling costs, smaller exhaust duct size, and smaller emissions control equipment sizes. The objective of this project was to conduct techno-economic analyses and an engineering design of the MBB project and to support this work with thermodynamic analyses and oxy-coal burner testing. Techno-economic analyses of GTI’s pressurized oxy-coal fired MBB technology found that the overall plant with compressed CO2 has an efficiency of 31.6%. This is a significant increase over calculated 29.2% efficiency of first generation oxy-coal plants. Cost of electricity (COE) for the pressurized MBB supercritical steam power plant with CO2 capture and compression was calculated to be 134% of the COE for an air-coal supercritical steam power plant with no CO2 capture. This compares positively with a calculated COE for first generation oxy-coal supercritical steam power plants with CO2 capture and compression of 164%. The COE for the MBB power plant is found to meet the U.S. Department of Energy (DOE) target of 135%, before any plant optimization. The MBB power plant was also determined to be simpler than other oxy-coal power plants with a 17% lower capital cost. No other known combustion technology can produce higher efficiencies or lower COE when CO2 capture and compression are included. A thermodynamic enthalpy and exergy analysis

  6. Studying the specific features pertinent to combustion of chars obtained from coals having different degrees of metamorphism and biomass chars

    Science.gov (United States)

    Bestsennyi, I. V.; Shchudlo, T. S.; Dunaevskaya, N. I.; Topal, A. I.

    2013-12-01

    Better conditions for igniting low-reaction coal (anthracite) can be obtained, higher fuel burnout ratio can be achieved, and the problem of shortage of a certain grade of coal can be solved by firing coal mixtures and by combusting coal jointly with solid biomass in coal-fired boilers. Results from studying the synergetic effect that had been revealed previously during the combustion of coal mixtures in flames are presented. A similar effect was also obtained during joint combustion of coal and wood in a flame. The kinetics pertinent to combustion of char mixtures obtained from coals characterized by different degrees of metamorphism and the kinetics pertinent to combustion of wood chars were studied on the RSK-1D laboratory setup. It was found from the experiments that the combustion rate of char mixtures obtained from coals having close degrees of metamorphism is equal to the value determined as a weighted mean rate with respect to the content of carbon. The combustion rate of char mixtures obtained from coals having essentially different degrees of metamorphism is close to the combustion rate of more reactive coal initially in the process and to the combustion rate of less reactive coal at the end of the process. A dependence of the specific burnout rate of carbon contained in the char of two wood fractions on reciprocal temperature in the range 663—833 K is obtained. The combustion mode of an experimental sample is determined together with the reaction rate constant and activation energy.

  7. Comparative analysis for performance of brown coal combustion in a vortex furnace with improved design

    Science.gov (United States)

    Krasinsky, D. V.

    2016-09-01

    Comparative study of 3D numerical simulation of fluid flow and coal-firing processes was applied for flame combustion of Kansk-Achinsk brown coal in a vortex furnace of improved design with bottom injection of secondary air. The analysis of engineering performance of this furnace was carried out for several operational modes as a function of coal grinding fineness and coal input rate. The preferable operational regime for furnace was found.

  8. Dioxin emissions from coal combustion in domestic stove: Formation in the chimney and coal chlorine content influence

    Directory of Open Access Journals (Sweden)

    Paradiz Bostjan

    2015-01-01

    Full Text Available Combustion experiments conducted in domestic stove burning hard coal demonstrated a predominant influence of the coal chlorine content on the PCDD/F emissions, together with a pronounced effect of the flue gas temperature. PCDD/F concentrations of over 100 ng TEQ/m3, three orders of magnitude higher than in a modern waste incinerator, were measured in the flue gases of a domestic stove when combusting high chlorine coal (0.31 %. The PCDD/F concentrations in the flue gases dropped below 0,5 ng TEQ/m3, when low chlorine coal (0.07 % was used. When low chlorine coal was impregnated with NaCl to obtain 0.38 % chlorine content, the emission of the PCDD/Fs increased by two orders of magnitude. Pronounced nonlinearity of the PCDD/F concentrations related to chlorine content in the coal was observed. The combustion of the high chlorine coal yielded PCDD/F concentrations in flue gases one order of magnitude lower in a fan cooled chimney when compared to an insulated one, thus indicating formation in the chimney. The influence of flue gas temperature on the PCDD/F emissions was less pronounced when burning low chlorine coal. The predominant pathway of the PCDD/F emissions is via flue gases, 99 % of the TEQ in the case of the high chlorine coal for insulated chimney.

  9. Recent trend in coal utilization technology. Coal utilization workshop

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chon Ho; Son, Ja Ek; Lee, In Chul; Jin, Kyung Tae; Kim, Seong Soo [Korea Inst. of Energy Research, Taejon (Korea, Republic of)

    1995-12-01

    The 11th Korea-U.S.A. joint workshop on coal utilization technology was held in somerset, Pennsylvania, U.S.A. from october 2 to 3, 1995. In the opening ceremony, Dr.C. Low-el Miller, associate deputy assistant secretary of office of clean coal technology, U.S.DOE, gave congratulatory remarks and Dr. Young Mok Son, president of KIER, made a keynote address. In this workshop, 30 papers were presented in the fields of emission control technology, advanced power generation systems, and advanced coal cleaning and liquid fuels. Especially, from the Korean side, not only KIER but also other private research institutes and major engineering companies including KEPCO, Daewoo Institute of Construction Technology, Jindo Engineering and Construction Co. Daewoo Institute for Advanced Engineering and universities participated in this workshop, reflecting their great interests. Attendants actively discussed about various coal utilization technologies and exchanged scientific and technical information on the state-of-art clean coal technologies under development. (author)

  10. Combustion characterization of coals for industrial applications. Final technical report, January 1, 1981-May 29, 1985

    Energy Technology Data Exchange (ETDEWEB)

    Nsakala, N.; Patel, R.L.; Lao, T.C.

    1985-03-01

    In-depth fundamental information was obtained from a two-inch inner diameter laminar flow reactor referred to as the Drop Tube Furnace System (DTFS). This information consists of the following: (1) pyrolysis kinetic characteristics of four coals of various rank (Texas lignite, Montana subbituminous, Alabama high volatile bituminous, and Pennsylvania anthracite); and (2) combustion kinetic studies of chars produced from the foregoing parent coals. A number of standard ASTM and special in-house bench scale tests were also performed on the coals and chars prepared therefrom to characterize their physicochemical properties. The pilot scale (500,000 Btu/hr) Controlled Mixing History Furnace (CMHF) was used to determine the effect of staged combustion on NO/sub x/ emissions control from an overall combustion performance of the Alabama high volatile bituminous coal. The quantitative fundamental data developed from this study indicate significant differences in coal/char chemical, physical, and reactivity characteristics, which should be useful to those interested in modeling coal combustion and pyrolysis processes. These results underscore the fact that coal selection is one of the keys governing a successful coal conversion/utilization process. The combustion kinetic information obtained on the high volatile bituminous coal has been used in conjunction with combustion engineering's proprietary mathematical models to predict the combustion performance of this coal in the Controlled Mixing History Furnace. Comparison of the predicted data with the experimental results shows a virtually one-to-one scale-up from the DTFS to the CMHF. These data should provide vital information to designers in the area of carbon burnout and NO/sub x/ reduction for large scale coal utilization applications. 31 refs., 28 figs., 17 tabs.

  11. UTILIZATION OF LOW NOx COAL COMBUSTION BY-PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    J.Y. Hwang; X. Huang; M.G. McKimpson; R.E. Tieder; A.M. Hein; J.M. Gillis; D.C. Popko; K.L. Paxton; Z. Li; X. Liu; X. Song; R.I. Kramer

    1998-12-01

    Low NO{sub x} combustion practices are critical for reducing NO{sub x} emissions from power plants. These low NO{sub x} combustion practices, however, generate high residual carbon contents in the fly ash produced. These high carbon contents threaten utilization of this combustion by-product. This research has successfully developed a separation technology to render fly ash into useful, quality-controlled materials. This technology offers great flexibility and has been shown to be applicable to all of the fly ashes tested (more than 10). The separated materials can be utilized in traditional fly ash applications, such as cement and concrete, as well as in nontraditional applications such as plastic fillers, metal matrix composites, refractories, and carbon adsorbents. Technologies to use beneficiated fly ash in these applications are being successfully developed. In the future, we will continue to refine the separation and utilization technologies to expand the utilization of fly ash. The disposal of more than 31 million tons of fly ash per year is an important environmental issue. With continued development, it will be possible to increase economic, energy and environmental benefits by re-directing more of this fly ash into useful materials.

  12. Investigation of formation of nitrogen compounds in coal combustion. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Blair, D.W.; Crane, I.D.; Wendt, J.O.L.

    1983-10-01

    This is the final report on DOE contract number DE-AC21-80MC14061. It concerns the formation of nitrogen oxide from fuel-bound nitrogen during coal combustion. The work reported was divided into three tasks. They addressed problems of time-resolving pyrolysis rates of coal under simulated combustion conditions, the combustion of the tar that results from such pyrolysis, and theoretical modeling of the pyrolysis process. In all of these tasks, special attention was devoted to the fate of coal nitrogen. The first two tasks were performed by Exxon Research and Engineering Company. 49 references.

  13. Coal Combustion Wastes Reuse in Low Energy Artificial Aggregates Manufacturing

    Directory of Open Access Journals (Sweden)

    Raffaele Cioffi

    2013-10-01

    Full Text Available Sustainable building material design relies mostly on energy saving processes, decrease of raw materials consumption, and increase of waste and by-products recycling. Natural and lightweight artificial aggregates production implies relevant environmental impact. This paper addresses both the issues of residues recycling and energy optimization. Particularly, three coal combustion wastes (Weathered Fly Ash, WFA; Wastewater Treatment Sludge, WTS; Desulfurization Device Sludge, DDS supplied by the Italian electric utility company (ENEL have been employed in the manufacture of cold bonded artificial aggregates. Previously, the residues have been characterized in terms of chemical and mineralogical compositions, water content, particle size distribution, and heavy metal release behavior. These wastes have been used in the mix design of binding systems with the only addition of lime. Finally, the artificial aggregates have been submitted to physical, mechanical, and leaching testing, revealing that they are potentially suitable for many civil engineering applications.

  14. Coal Combustion Wastes Reuse in Low Energy Artificial Aggregates Manufacturing.

    Science.gov (United States)

    Ferone, Claudio; Colangelo, Francesco; Messina, Francesco; Iucolano, Fabio; Liguori, Barbara; Cioffi, Raffaele

    2013-10-31

    Sustainable building material design relies mostly on energy saving processes, decrease of raw materials consumption, and increase of waste and by-products recycling. Natural and lightweight artificial aggregates production implies relevant environmental impact. This paper addresses both the issues of residues recycling and energy optimization. Particularly, three coal combustion wastes (Weathered Fly Ash, WFA; Wastewater Treatment Sludge, WTS; Desulfurization Device Sludge, DDS) supplied by the Italian electric utility company (ENEL) have been employed in the manufacture of cold bonded artificial aggregates. Previously, the residues have been characterized in terms of chemical and mineralogical compositions, water content, particle size distribution, and heavy metal release behavior. These wastes have been used in the mix design of binding systems with the only addition of lime. Finally, the artificial aggregates have been submitted to physical, mechanical, and leaching testing, revealing that they are potentially suitable for many civil engineering applications.

  15. Influence of Process Parameters on Coal Combustion Performance

    DEFF Research Database (Denmark)

    Lans, Robert Pieter Van Der

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

  16. Thermally induced structural changes in coal combustion. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Flagan, R.C.; Gavalas, G.R.

    1992-01-01

    The effects of the temperature-time history during coal devolitization and oxidation on the physical properties and the reactivity of resulting char were studied experimentally for temperatures and residence times typical of pulverized combustion. Experiments were also carried out at somewhat lower temperatures and correspondingly longer residence times. An electrically heated laminar flow reactor was used to generate char and measure the rates of oxidation at gas temperatures about 1600K. Partially oxidized chars were extracted and characterized by gas adsorption and mercury porosimetry, optical and scanning electron microscopy, and oxidation in a thermogravimetric analysis system (TGA). A different series of experiments was conducted using a quadrople electrodynamic balance. Single particles were suspended electrodynamically and heated by an infrared laser in an inert or oxygen-containing atmosphere. During the laser heating, measurements were taken of particle mass, size/shape, and temperature.

  17. Utilization of coal combustion fly ash in terracotta bodies

    Energy Technology Data Exchange (ETDEWEB)

    Kara, A.; Kurama, S. [Dept. of Materials Science and Engineering, Anadolu Univ., Eskisehir (Turkey); Kurama, H.; Kara, Y. [Osmangazi Univ., Mining Engineering Dept., Eskisehir (Turkey)

    2004-07-01

    In this present work, coal combustion fly ash from a power plant in Turkey was used in combination with a traditional raw material in terracotta production with the aim of having a product with improved physico-mechanical properties and lower production cost. Several compositions were prepared by adding different amounts of fly ash (ranging from 0 to 20%) in a yellow firing terracotta formulation and shaped by wet pressing. Following firing at a suitable temperature, some of the physical properties of the resultant tiles were determined as a function of the fly ash content. A combination of XRD, SEM and EDX techniques were also employed to correlate the properties with the phase composition. The results indicated that fly ash could be utilized easily in certain amounts in such an application. (orig.)

  18. Chromium speciation in coal and biomass co-combustion products.

    Science.gov (United States)

    Stam, Arthur F; Meij, Ruud; Te Winkel, Henk; Eijk, Ronald J van; Huggins, Frank E; Brem, Gerrit

    2011-03-15

    Chromium speciation is vital for the toxicity of products resulting from co-combustion of coal and biomass. Therefore, understanding of formation processes has been studied using a combination of X-ray absorption fine structure (XAFS) spectroscopy and thermodynamic equilibrium calculations. The influence of cofiring on Cr speciation is very dependent on the type of fuel. Cr(VI) contents in the investigated fly ash samples from coal and cofiring average around 7% of the total chromium. An exception is cofiring 7-28% wood for which ashes exhibited Cr(VI) concentrations of 12-16% of the total chromium. Measurements are in line with thermodynamic predictions: RE factors of Cr around 1 are in line with volatile Cr only above 1400 °C; lower Cr(VI) concentrations with lower oxygen content and Cr(III) dissolved in aluminosilicate glass. Stability of Cr(VI) below 700 °C does not correlate with Cr(VI) concentrations found in the combustion products. It is indicated that Cr(VI) formation is a high-temperature process dependent on Cr evaporation (mode of occurrence in fuel, promoted by organic association), oxidation (local oxygen content), and formation of solid chromates (promoted by presence of free lime (CaO) in the ash). CaCrO(4)(s) is a probable chemical form but, given different leachable fractions (varying from 25 to 100%), different forms of Cr(VI) must be present. Clay-bound Cr is likely to dissolve in the aluminosilicate glass phase during melting of the clay.

  19. 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.

  20. RESEARCH OF LEVEL OF SPONTANEOUS COMBUSTION ON COAL HEAPS GENESIS DANGER

    Directory of Open Access Journals (Sweden)

    Vlastimil MONI

    2014-07-01

    Full Text Available The article presents the summary of information about the spontaneous combustion of brown coal mass on coal heaps. It describes the procedure “The evaluation of the degree of the danger for the genesis of the spontaneous combustion of coal on coal heaps”. The evaluation includes analysis of important influencing factors. The conclusion of this article contains definite text of the proposition. It will be verified in the last year of the solution of this project TA01020351 – program ALFA.

  1. Preparation and combustion of coal-water fuel from the Sin Pun coal deposit, southern Thailand

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    In response to an inquiry by the Department of Mineral Resources in Thailand, the Energy & Environmental Research Center (EERC) prepared a program to assess the responsiveness of Sin Pun lignite to the temperature and pressure conditions of hot-water drying. The results indicate that drying made several improvements in the coal, notably increases in heating value and carbon content and reductions in equilibrium moisture and oxygen content. The equilibrium moisture content decreased from 27 wt% for the raw coal to about 15 wt% for the hot-water-dried (HWD) coals. The energy density for a pumpable coal-water fuel (CWF) indicates an increase from 4500 to 6100 Btu/lb by hot-water drying. Approximately 650 lb of HWD Sin Pun CWF were fired in the EERC`s combustion test facility. The fuel burned extremely well, with no feed problems noted during the course of the test. Fouling and slagging deposits each indicated a very low rate of ash deposition, with only a dusty layer formed on the cooled metal surfaces. The combustor was operated at between 20% and 25% excess air, resulting in a flue gas SO{sub 2} concentration averaging approximately 6500 parts per million.

  2. Structure Based Predictive Model for Coal Char Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Robert Hurt; Joseph Calo; Robert Essenhigh; Christopher Hadad

    2000-12-30

    This unique collaborative project has taken a very fundamental look at the origin of structure, and combustion reactivity of coal chars. It was a combined experimental and theoretical effort involving three universities and collaborators from universities outside the U.S. and from U.S. National Laboratories and contract research companies. The project goal was to improve our understanding of char structure and behavior by examining the fundamental chemistry of its polyaromatic building blocks. The project team investigated the elementary oxidative attack on polyaromatic systems, and coupled with a study of the assembly processes that convert these polyaromatic clusters to mature carbon materials (or chars). We believe that the work done in this project has defined a powerful new science-based approach to the understanding of char behavior. The work on aromatic oxidation pathways made extensive use of computational chemistry, and was led by Professor Christopher Hadad in the Department of Chemistry at Ohio State University. Laboratory experiments on char structure, properties, and combustion reactivity were carried out at both OSU and Brown, led by Principle Investigators Joseph Calo, Robert Essenhigh, and Robert Hurt. Modeling activities were divided into two parts: first unique models of crystal structure development were formulated by the team at Brown (PI'S Hurt and Calo) with input from Boston University and significant collaboration with Dr. Alan Kerstein at Sandia and with Dr. Zhong-Ying chen at SAIC. Secondly, new combustion models were developed and tested, led by Professor Essenhigh at OSU, Dieter Foertsch (a collaborator at the University of Stuttgart), and Professor Hurt at Brown. One product of this work is the CBK8 model of carbon burnout, which has already found practical use in CFD codes and in other numerical models of pulverized fuel combustion processes, such as EPRI's NOxLOI Predictor. The remainder of the report consists of detailed

  3. High Impact Technology Compact Combustion (HITCC) Compact Core Technologies

    Science.gov (United States)

    2016-01-01

    the CO and CO2 net reaction rates from the FGM. This, in turn, provides another benefit . That is, the source term in YC is not just now dependent on...AFRL-RQ-WP-TR-2016-0010 HIGH IMPACT TECHNOLOGY COMPACT COMBUSTION (HITCC) COMPACT CORE TECHNOLOGIES Andrew W. Caswell Combustion...information exchange, and its publication does not constitute the Government’s approval or disapproval of its ideas or findings. *Disseminated

  4. State perspectives on clean coal technology deployment

    Energy Technology Data Exchange (ETDEWEB)

    Moreland, T. [State of Illinois Washington Office, Washington, DC (United States)

    1997-12-31

    State governments have been funding partners in the Clean Coal Technology program since its beginnings. Today, regulatory and market uncertainties and tight budgets have reduced state investment in energy R and D, but states have developed program initiatives in support of deployment. State officials think that the federal government must continue to support these technologies in the deployment phase. Discussions of national energy policy must include attention to the Clean Coal Technology program and its accomplishments.

  5. Low temperature combustion of organic coal-water fuel droplets containing petrochemicals while soaring in a combustion chamber model

    Directory of Open Access Journals (Sweden)

    Valiullin Timur R.

    2017-01-01

    Full Text Available The paper examines the integral characteristics (minimum temperature, ignition delay times of stable combustion initiation of organic coal-water fuel droplets (initial radius is 0.3-1.5 mm in the oxidizer flow (the temperature and velocity varied in ranges 500-900 K, 0.5-3 m/s. The main components of organic coal-water fuel were: brown coal particles, filter-cakes obtained in coal processing, waste engine, and turbine oils. The different modes of soaring and ignition of organic coal-water fuel have been established. The conditions have been set under which it is possible to implement the sustainable soaring and ignition of organic coal-water fuel droplets. We have compared the ignition characteristics with those defined in the traditional approach (based on placing the droplets on a low-inertia thermocouple junction into the combustion chamber. The paper shows the scale of the influence of heat sink over the thermocouple junction on ignition inertia. An original technique for releasing organic coal-water fuel droplets to the combustion chamber was proposed and tested. The limitations of this technique and the prospects of experimental results for the optimization of energy equipment operation were also formulated.

  6. Toxic substances from coal combustion -- A comprehensive assessment

    Energy Technology Data Exchange (ETDEWEB)

    Senior, C.L.; Huggins, F.E.; Huffman, G.P.; Shan, N.; Yap, N.; Wendt, J.O.L.; Seames, W.; Ames, M.R.; Sarofim, A.F.; Swenson, S.; Lighty, J.; Kolker, A.; Finkelman, R.; Palmer, C.; Mroczkowski, S.; Helble, J.; Mamani-Paco, R.; Sterling, R.; Dunham, G.; Miller, S.

    2000-08-17

    The final program review meeting of Phase II was held on June 22 in Salt Lake City. The goals of the meeting were to present work in progress and to identify the remaining critical experiments or analyses, particularly those involving collaboration among various groups. The information presented at the meeting is summarized in this report. Remaining fixed bed, bench-scale experiments at EERC were discussed. There are more ash samples which can be run. Of particular interest are high carbon ash samples to be generated by the University of Arizona this summer and some ash-derived sorbents that EERC has evaluated on a different program. The use of separation techniques (electrostatic or magnetic) was also discussed as a way to understand the active components in the ash with respect to mercury. XAFS analysis of leached and unleached ash samples from the University of Arizona was given a high priority. In order to better understand the fixed bed test results, CCSEM and Moessbauer analyses of those ash samples need to be completed. Utah plans to analyze the ash from the single particle combustion experiments for those major elements not measured by INAA. USGS must still complete mercury analyses on the whole coals and leaching residues. Priorities for further work at the SHRIMP-RG facility include arsenic on ash surfaces and mercury in sulfide minerals. Moessbauer analyses of coal samples from the University of Utah were completed; samples from the top and bottom layers of containers of five different coals showed little oxidation of pyrite in the top relative to the bottom except for Wyodak.

  7. Research on coal pyrolysis and combustion poly-generation system

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Mengxiang; Cen, Jianmeng; Li, Chao [Zhejiang Univ., Hangzhou (China). Inst. for Thermal Power Engineering] [and others

    2013-07-01

    A new poly-generation system combined coal combustion and pyrolysis has been developed for clean and high efficient utilization of coal. Coal is first pyrolyzed in a fluidized bed gasifier and produced gas is then purified and used for MeOH or DME production. Tar is collected during purification and can be processed to extract monocyclic aromatic hydrocarbons, polycyclic aromatic hydrocarbons and to make liquid fuels by hydrorefining. Semi-coke from the gasifier is burned in a CFB boiler for heat or power generation. A 12MW CFB gas, tar, heat and power poly-generation system was erected by Zhejiang University in cooperation with the Huainan Mining Industry (Group) Co., Ltd. in 2007. The experimental study focused on the two fluidized bed operation and characterization of gas, tar and char yields and compositions. The results showed that the system could operate stable, and produce about 0.12Nm{sup 3}/kg gas with 22MJ/Nm{sup 3} heating value and about 10wt.% tar when pyrolysis temperature between 500 and 600 C. The produced gases were mainly H{sub 2}, CH{sub 4}, N{sub 2}, CO, CO{sub 2}, C{sub 2}H{sub 4}, C{sub 2}H{sub 6}, C{sub 3}H{sub 6} and C{sub 3}H{sub 8}. Gas component concentrations were 24.18, 36.29, 7.96, 5.6, 7.84, 11.70 and 3.28%, respectively. The CFB boiler run steadily, whether the gasifier run or not, and produced 12MW power.

  8. Pilot Demonstration of Technology for the Production of High Value Materials from the Ultra-Fine (PM2.5) Fraction of Coal Combustion Ash

    Energy Technology Data Exchange (ETDEWEB)

    T. L. Robl; J. G. Groppo; R. Rathbone; B. Marrs; R. Jewell

    2008-07-18

    polyethylene terphthalate filled polymers were prepared and subjected to SEM analysis to verify that the UFA was well dispersed. The addition of fillers increased the modulus of the HDPE composite, but decreased both the offset yield stress and offset yield strain, showing that the fillers essentially made the composite stiffer but the transition to plastic deformation occurred earlier in filled HDPE as stress was applied. Similar results were obtained with TPE, however, the decrease in either stress or strain at offset yield were not as significant. Dynamic mechanical analyses (DMA) were also completed and showed that although there were some alterations in the properties of the HDPE and TPE, the alterations are small, and more importantly, transition temperatures are not altered. The UFA materials were also tested in expanded urethanes, were improvements were made in the composites strength and stiffness, particularly for lighter weight materials. The results of limited flammability and fire safety testing were encouraging. A flowsheet was developed to produce an Ultra-Fine Ash (UFA) product from reclaimed coal-fired utility pond ash. The flowsheet is for an entry level product development scenario and additional production can be accommodated by increasing operating hours and/or installing replicate circuits. Unit process design was based on experimental results obtained throughout the project and cost estimates were derived from single vendor quotes. The installation cost of this plant is estimated to be $2.1M.

  9. Carbon and oxygen isotopic composition of coal and carbon dioxide derived from laboratory coal combustion: A preliminary study

    Science.gov (United States)

    Warwick, Peter; Ruppert, Leslie F.

    2016-01-01

    The concentration of carbon dioxide (CO2) in the atmosphere has dramatically increased from the start of the industrial revolution in the mid-1700s to present levels exceeding 400 ppm. Carbon dioxide derived from fossil fuel combustion is a greenhouse gas and a major contributor to on-going climate change. Carbon and oxygen stable isotope geochemistry is a useful tool to help model and predict the contributions of anthropogenic sources of CO2 in the global carbon cycle. Surprisingly few studies have addressed the carbon and oxygen isotopic composition of CO2 derived from coal combustion. The goal of this study is to document the relationships between the carbon and oxygen isotope signatures of coal and signatures of the CO2 produced from laboratory coal combustion in atmospheric conditions.Six coal samples were selected that represent various geologic ages (Carboniferous to Tertiary) and coal ranks (lignite to bituminous). Duplicate splits of the six coal samples were ignited and partially combusted in the laboratory at atmospheric conditions. The resulting coal-combustion gases were collected and the molecular composition of the collected gases and isotopic analyses of δ13C of CO2, δ13C of CH4, and δ18O of CO2 were analysed by a commercial laboratory. Splits (~ 1 g) of the un-combusted dried ground coal samples were analyzed for δ13C and δ18O by the U.S. Geological Survey Reston Stable Isotope Laboratory.The major findings of this preliminary work indicate that the isotopic signatures of δ13C (relative to the Vienna Pee Dee Belemnite scale, VPDB) of CO2 resulting from coal combustion are similar to the δ13CVPDB signature of the bulk coal (− 28.46 to − 23.86 ‰) and are not similar to atmospheric δ13CVPDB of CO2 (~ − 8 ‰, see http://www.esrl.noaa.gov/gmd/outreach/isotopes/c13tellsus.html). The δ18O values of bulk coal are strongly correlated to the coal dry ash yields and appear to have little or no influence on the δ18O values of CO2

  10. Mercury emissions from coal combustion in Silesia, analysis using geostatistics

    Science.gov (United States)

    Zasina, Damian; Zawadzki, Jaroslaw

    2015-04-01

    Data provided by the UNEP's report on mercury [1] shows that solid fuel combustion in significant source of mercury emission to air. Silesia, located in southwestern Poland, is notably affected by mercury emission due to being one of the most industrialized Polish regions: the place of coal mining, production of metals, stone mining, mineral quarrying and chemical industry. Moreover, Silesia is the region with high population density. People are exposed to severe risk of mercury emitted from both: industrial and domestic sources (i.e. small household furnaces). Small sources have significant contribution to total emission of mercury. Official and statistical analysis, including prepared for international purposes [2] did not provide data about spatial distribution of the mercury emitted to air, however number of analysis on Polish public power and energy sector had been prepared so far [3; 4]. The distribution of locations exposed for mercury emission from small domestic sources is interesting matter merging information from various sources: statistical, economical and environmental. This paper presents geostatistical approach to distibution of mercury emission from coal combustion. Analysed data organized in 2 independent levels: individual, bottom-up approach derived from national emission reporting system [5; 6] and top down - regional data calculated basing on official statistics [7]. Analysis, that will be presented, will include comparison of spatial distributions of mercury emission using data derived from sources mentioned above. Investigation will include three voivodeships of Poland: Lower Silesian, Opole (voivodeship) and Silesian using selected geostatistical methodologies including ordinary kriging [8]. References [1] UNEP. Global Mercury Assessment 2013: Sources, Emissions, Releases and Environmental Transport. UNEP Chemicals Branch, Geneva, Switzerland, 2013. [2] NCEM. Poland's Informative Inventory Report 2014. NCEM at the IEP-NRI, 2014. http

  11. The development of coal-based technologies for Department of Defense facilities: Phase 1 final report. Volume 1: Technical report

    Energy Technology Data Exchange (ETDEWEB)

    Miller, B.G.; Morrison, J.L.; Pisupati, S.V. [Pennsylvania State Univ., University Park, PA (United States). Energy and Fuels Research Center] [and others

    1997-01-31

    The first phase of a three-phase project investigating the development of coal-based technologies for Department of Defense facilities has been completed. The objectives of the project are to: decrease DOD`s dependence on foreign oil and increase its use of coal; promote public and private sector deployment of technologies for utilizing coal-based fuels in oil-designed combustion equipment; and provide a continuing environment for research and development of coal-based fuel technologies for small-scale applications at a time when market conditions in the US are not favorable for the introduction of coal-fired equipment in the commercial and industrial capacity ranges. The Phase 1 activities were focused on developing clean, coal-based combustion technologies for the utilization of both micronized coal-water mixtures (MCWMs) and dry, micronized coal (DMC) in fuel oil-designed industrial boilers. The specific objective in Phase 1 was to deliver fully engineered retrofit options for a fuel oil-designed watertube boiler located on a DOD installation to fire either MCWM or DMC. This was achieved through a project consisting of fundamental, pilot-sale, and demonstration-scale activities investigating coal beneficiation and preparation, and MCWM and DMC combustion performance. In addition, detailed engineering designs and an economic analysis were conducted for a boiler located at the Naval Surface Warfare Center, near Crane, Indiana. Results are reported on MCWM and DMC combustion performance evaluation; engineering design; and cost/economic analysis.

  12. Working of spontaneously combustible coal seams with automatic air pressure regulation in the excavation field

    Energy Technology Data Exchange (ETDEWEB)

    Golik, A.S.; Churikov, Yu.V.; Troyan, N.P.

    1980-01-01

    A demonstration is made of the effectiveness of using an automatic air pressure control system during the working of spontaneously combustible coal seams in order to control endogenic fires and gas. 2 figures.

  13. The Simulation of Influence of Different Coals on the Circulating Fluidized Bed Boiler's Combustion Performance

    Institute of Scientific and Technical Information of China (English)

    Yumei Yong; Qinggang Lu

    2003-01-01

    The combustion performance of the boiler largely depends on the coal type. Lots of experimental research shows that different fuels have different combustion characteristics. It is obvious that fuel will change the whole operating performance of Circulating Fluidized Bed Combustion (CFBC). We know even in a pilot-scale running boiler, the measurement of some parameters is difficult and costly. Therefore, we developed the way of simulation to evaluate the combustion performance of Chinese coals in CFB. The simulation results show that,different coals will result in different coal particle diameter and comminution depending on their mineral component and the change will affect the distribution of ash in CFBC system. In a word, the computational results are in accordance with experimental results qualitatively but there are some differences quantitatively.

  14. Coal Combustion Residual Beneficial Use Evaluation: Fly Ash Concrete and FGD Gypsum Wallboard

    Science.gov (United States)

    This page contains documents related to the evaluation of coal combustion residual beneficial use of fly ash concrete and FGD gypsum wallboard including the evaluation itself and the accompanying appendices

  15. Pressurized circulating fluidized bed combustion technology

    Energy Technology Data Exchange (ETDEWEB)

    Vasquez-Malebran, S.; Anglesea, W.T. [Fluent Europe Limited, Sheffield (United Kingdom)

    1998-12-31

    This report describes how the FLUENT computations fluid dynamics code has been provided with a granular (gas-solids), multiphase flow-modelling capability in order to simulate the operation of a circulating fluidized bed combustion chamber. The new multiphase module solves the conservation equations for each phase on an Eulerian basis and it currently enables gas phase reactions and interphase heat and momentum transfer to be modelled. Because of fundng restrictions, the module has not yet been provided with a general capability for modelling interphase mass transfer and therefore approximations have to be made when simulating coal combustion. Having developed the code and carried out basic testing, it has been used to simulate one set of conditions in the circulating fluidized bed combustion test facility operated by RWE Energie AG at Niederaussem Germany. Considering the simplifications made in this simulation, the level of agreement between the code results and the available measurements and observations is very encouraging. 18 refs., 5 figs., 2 tabs.

  16. Fundamental and Technical Challenges for a Compatible Design Scheme of Oxyfuel Combustion Technology

    Directory of Open Access Journals (Sweden)

    Chuguang Zheng

    2015-03-01

    Full Text Available Oxyfuel combustion with carbon capture and sequestration (CCS is a carbon-reduction technology for use in large-scale coal-fired power plants. Significant progress has been achieved in the research and development of this technology during its scaling up from 0.4 MWth to 3 MWth and 35 MWth by the combined efforts of universities and industries in China. A prefeasibility study on a 200 MWe large-scale demonstration has progressed well, and is ready for implementation. The overall research development and demonstration (RD&D roadmap for oxyfuel combustion in China has become a critical component of the global RD&D roadmap for oxyfuel combustion. An air combustion/oxyfuel combustion compatible design philosophy was developed during the RD&D process. In this paper, we briefly address fundamental research and technology innovation efforts regarding several technical challenges, including combustion stability, heat transfer, system operation, mineral impurities, and corrosion. To further reduce the cost of carbon capture, in addition to the large-scale deployment of oxyfuel technology, increasing interest is anticipated in the novel and next-generation oxyfuel combustion technologies that are briefly introduced here, including a new oxygen-production concept and flameless oxyfuel combustion.

  17. Low-rank coal study: national needs for resource development. Volume 3. Technology evaluation

    Energy Technology Data Exchange (ETDEWEB)

    1980-11-01

    Technologies applicable to the development and use of low-rank coals are analyzed in order to identify specific needs for research, development, and demonstration (RD and D). Major sections of the report address the following technologies: extraction; transportation; preparation, handling and storage; conventional combustion and environmental control technology; gasification; liquefaction; and pyrolysis. Each of these sections contains an introduction and summary of the key issues with regard to subbituminous coal and lignite; description of all relevant technology, both existing and under development; a description of related environmental control technology; an evaluation of the effects of low-rank coal properties on the technology; and summaries of current commercial status of the technology and/or current RD and D projects relevant to low-rank coals.

  18. Characteristics of particulate carbon emissions from real-world Chinese coal combustion.

    Science.gov (United States)

    Zhang, Yuanxun; Schauer, James Jay; Zhang, Yuanhang; Zeng, Limin; Wei, Yongjie; Liu, Yuan; Shao, Min

    2008-07-15

    Particulate matter emissions from a series of different Chinese coal combustion systems were collected and analyzed for elemental and organic carbon (EC, OC), and molecular markers. Emissions from both industrial boilers and residential stoves were investigated. The coal used in this study included anthracite, bituminite, and brown coal, as well as commonly used coal briquettes produced in China for residential coal combustion. Results show significant differences in the contribution of carbonaceous species to particulate mass emissions. Industrial boilers had much higher burn out of carbon yielding particulate matter emissions with much lower levels of OC, EC, and speciated organic compounds, while residential stoves had significantly higher emissions of carbonaceous particulate matter with emission rates of approximately 100 times higher than that of industrial boilers. Quantified organic compounds emitted from industrial boilers were dominated by oxygenated compounds, of which 46-68% were organic acids, whereas the dominate species quantified in the emissions from residential stoves were PAHs (38%) and n-alkanes (20%). An important observation was the fact that emission factors of PAHs and the distribution of hopanoids were different among the emissions from industrial and residential coal combustion even using the same coal for combustion. Although particulate matter emissions from industrial and residential combustion were different in many regards, picene was detected in all samples with detectable OC mass concentrations, which supports the use of this organic tracer for OC from all types of coal combustion. 17alpha(H),21beta(H)-29-norhopane was the predominant hopanoid in coal combustion emissions, which is different from mobile source emissions and may be used to distinguish emissions from these different fossil fuel sources.

  19. Numerical Simulation of Oxy-coal Combustion for a Swirl Burner with EDC Model

    Institute of Scientific and Technical Information of China (English)

    崔凯; 刘冰; 吴玉新; 杨海瑞; 吕俊复; 张海

    2014-01-01

    The characteristics of oxy-coal combustion for a swirl burner with a specially designed preheating chamber are studied numerically. In order to increase the accuracy in the prediction of flame temperature and igni-tion position, eddy dissipation concept (EDC) model with a skeletal chemical reaction mechanism was adopted to describe the combustion of volatile matter. Simulation was conducted under six oxidant stream conditions with dif-ferent O2/N2/CO2 molar ratios:21/79/0, 30/70/0, 50/50/0, 21/0/79, 30/0/70 and 50/0/50. Results showed that O2 en-richment in the primary oxidant stream is in favor of combustion stabilization, acceleration of ignition and increase of maximum flame temperature, while the full substitution of N2 by CO2 in the oxidant stream delays ignition and decreases the maximum flame temperature. However, the overall flow field and flame shapes in these cases are very similar at the same flow rate of the primary oxidant stream. Combustion characteristics of the air-coal is similar to that of the oxy-coal with 30%O2 and 70%CO2 in the oxidant stream, indicating that the rear condition is suitable for retrofitting an air-coal fired boiler to an oxy-coal one. The swirl burner with a specially designed preheating chamber can increase flame temperature, accelerate ignition and enhance burning intensity of pulverized coal under oxy-coal combustion. Also, qualitative experimental validation indicated the burner can reduce the overall NOx emission under certain O2 enrichment and oxy-coal combustion conditions against the air-coal combustion.

  20. Inhibition Effect of Phosphorus Flame Retardants on the Fire Disasters Induced by Spontaneous Combustion of Coal

    Directory of Open Access Journals (Sweden)

    Yibo Tang

    2017-01-01

    Full Text Available Coal spontaneous combustion (CSC generally induces fire disasters in underground mines, thus causing serious casualties, environmental pollution, and property loss around the world. By using six P-containing additives to process three typical coal samples, this study investigated the variations of the self-ignition characteristics of the coal samples before and after treatment. The analysis was performed by combining thermogravimetric analysis/differential scanning calorimetry (TG/DSC Fourier transform infrared spectrometer (FTIR and low temperature oxidation. Experimental results showed that P-containing inhibitors could effectively restrain the heat emitted in the combustion of coal samples and therefore the ignition temperature of the coal samples was delayed at varying degrees. The combustion rate of the coal samples was reduced as well. At the temperatures ranging from 50°C to 150°C, the activation energy of the coal samples after the treatment was found to increase, which indicated that the coal samples were more difficult to be oxidized. After being treated with phosphorus flame retardants (PFRs, the content of several active groups represented by the C-O structure in the three coal samples was proved to be obviously changed. This suggested that PFRs could significantly inhibit the content of CO generated by the low temperature oxidation of coal, and the flame-retardant efficiency grew with the increasing temperature. At 200°C, the maximal inhibition efficiency reached approximately 85%.

  1. Technical evaluation: pressurized fluidized-bed combustion technology

    Energy Technology Data Exchange (ETDEWEB)

    Miller, S A; Vogel, G J; Gehl, S M; Hanway, Jr, J E; Henry, R F; Parker, K M; Smyk, E B; Swift, W M; Podolski, W F

    1982-04-01

    The technology of pressurized fluidized-bed combustion, particularly in its application to a coal-burning combined-cycle plant, is evaluated by examining the technical status of advanced-concept plant components - boiler system (combustor, air-handling and air-injection equipment, and heat exchangers); solids handling, injection, and ejection system; hot-gas cleanup equipment; instrumentation/control system; and the gas turbine - along with materials of plant construction. Environmental performance as well as energy efficiency are examined, and economic considerations are reviewed briefly. The evaluation concludes with a broad survey of the principal related research and development programs in the United States and other countries, a foreview of the most likely technological developments, and a summary of unresolved technical issues and problems.

  2. NO sub x reduction measures in coal combustion. NO sub x -mindernde Massnahmen bei der Kohleverbrennung

    Energy Technology Data Exchange (ETDEWEB)

    Hoelter, H.; Reichert, W.

    1987-03-26

    It is a well-known practice to design the coal dust burners in the combustion of coal in such a way that, by the guidance of the combustion air, they produce less NO{sub x} than usual. It is also a well-known practice to reduce the amount of NO{sub x} in the flue gases of fossil combustion plants by means of catalysts. According to the invention, the knowledge has now been gained that in the case of certain types of coal, preferably coal with a high content of volatile components, preheating of the coal substantially contributes to a reduction of the amount of NO{sub x} in the combustion. The preheating can lead up to the range of low temperature carbonization gas. In the case of fluidized bed firing systems, the coal is fed above the fluidized bed and, in the case of jet firing systems, the feeding of the preheated coal into the combustion chamber takes place by means of the nozzles. (orig.).

  3. Coal slurry solids/coal fluidized bed combustion by-product mixtures as plant growth media

    Science.gov (United States)

    Darmody, R.G.; Green, W.P.; Dreher, G.B.

    1998-01-01

    Fine-textured, pyritic waste produced by coal cleaning is stored in slurry settling ponds that eventually require reclamation. Conventionally, reclamation involves covering the dewatered coal slurry solids (CSS) with 1.3 m of soil to allow plant growth and prevent acid generation by pyrite oxidation. This study was conducted to determine the feasiblity of a less costly reclamation approach that would eliminate the soil cover and allow direct seeding of plants into amended CSS materials. Potential acidity of the CSS would be neutralized by additions of fluidized-bed combustion by-product (FBCB), an alkaline by-product of coal combustion. The experiment involved two sources of CSS and FBCB materials from Illinois. Birdsfoot trefoil (Lotus corniculatus L.), tall fescue (Festuca arundinacea Schreb.), and sweet clover (Melilotus officinalis (L.) Lam.) were seeded in the greenhouse into pots containing mixtures of the materials. CSS-1 had a high CaCO3:FeS2 ratio and needed no FBCB added to compensate for its potential acidity. CSS-2 was mixed with the FBCB materials to neutralize potential acidity (labeled Mix A and B). Initial pH was 5.6, 8.8, and 9.2 for the CSS-1, Mix A, and Mix B materials, respectively. At the end of the 70-day experiment, pH was 5.9 for all mixtures. Tall fescue and sweet clover grew well in all the treatments, but birdsfoot trefoil had poor emergence and survival. Elevated tissue levels of B, Cd, and Se were found in some plants. Salinity, low moisture holding capacity, and potentially phytotoxic B may limit the efficacy of this reclamation method.

  4. Co-combustion of coal and SRF in an entrained flow reactor: a preliminary study

    DEFF Research Database (Denmark)

    Wu, Hao; Glarborg, Peter; Frandsen, Flemming;

    2009-01-01

    Investigations on co-firing of SRF with two kinds of bituminous coal were carried out in an entrained flow reactor. The experimental results showed that co-combustion of coal and SRF increased the unburnt carbon in fly ashes. The emissions of NO and SO2 were reduced with an increasing share of SRF...

  5. 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.

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

    NARCIS (Netherlands)

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

    2015-01-01

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

  7. ASSESSING SPECIATION AND RELEASE OF HEAVY METALS FROM COAL COMBUSTION PRODUCTS

    Science.gov (United States)

    In this study, the speciation of heavy metals such as arsenic, selenium, lead, zinc and mercury in coal combustion products (CCPs) was evaluated using sequential extraction procedures. Coal fly ash, bottom ash and flue gas desulphurization (FGD) sludge samples were used in the ex...

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

    Science.gov (United States)

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

    2017-03-21

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

  9. PAH emissions from coal combustion and waste incineration.

    Science.gov (United States)

    Hsu, Wei Ting; Liu, Mei Chen; Hung, Pao Chen; Chang, Shu Hao; Chang, Moo Been

    2016-11-15

    The characteristics of PAHs that are emitted by a municipal waste incinerator (MWI) and coal-fired power plant are examined via intensive sampling. Results of flue gas sampling reveal the potential for PAH formation within the selective catalytic reduction (SCR) system of a coal-fired power plant. In the large-scale MWI, the removal efficiency of PAHs achieved with the pilot-scaled catalytic filter (CF) exceeds that achieved by activated carbon injection with a bag filter (ACI+BF) owing to the effective destruction of gas-phase contaminants by a catalyst. A significantly lower PAH concentration (1640ng/g) was measured in fly ash from a CF module than from an ACI+BF system (5650ng/g). Replacing the ACI+BF system with CF technology would significantly reduce the discharge factor (including emission and fly ash) of PAHs from 251.6 to 77.8mg/ton-waste. The emission factors of PAHs that are obtained using ACI+BF and the CF system in the MWI are 8.05 and 7.13mg/ton, respectively. However, the emission factor of MWI is significantly higher than that of coal-fired power plant (1.56mg/ton). From the perspective of total environmental management to reduce PAH emissions, replacing the original ACI+BF process with a CF system is expected to reduce environmental impact thereof.

  10. Relationships between composition and pulmonary toxicity of prototype particles from coal combustion and pyrolysis

    Science.gov (United States)

    The hypothesis that health effects associated with coal combustion fly-ash particles are exacerbated by the simultaneous presence of iron and soot was tested through two sets of experiments. The first set created prototype particles from complete and partial combustion, or oxygen...

  11. RELATIONSHIPS BETWEEN COMPOSITION AND PULMONARY TOXICITY OF PROTOTYPE PARTICLES FROM COAL COMBUSTION AND PYROLYSIS (MONTREAL, CANADA)

    Science.gov (United States)

    The hypothesis that health effects associated with coal combustion fly-ash particles are exacerbated by the simultaneous presence of iron and soot was tested through two sets of experiments. The first set created prototype particles from complete and partial combustion, or oxygen...

  12. Slagging characteristics of molten coal ash on silicon-aluminum combustion liners of boiler

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to study the slagging characteristics of boiler combustion liners during pulverized coal stream combustion,the slag samples on the surface of combustion liner were investigated by X-ray diffractometry,scan electron microscopy and energy dispersive X-ray analysis,and the transformation characteristics of the compositions and crystal phases were studied.The results show that the size of slag granules decreases as the slagging temperature increases;the crystallinity of coal ash I reduces to about 48.6% when the temperature is increased up to 1 350 ℃,and that of the coal ash Ⅱ reduces to about 65% when the temperature is increased up to 1 500 ℃;the encroachment of molten coal ash to the combustion liner is strengthened.At the same time,the diffusion and the segregation of the compositions in combustion liners have selectivity,which is in favor of enhancing the content of crystal phases,weakening the conglutination among molten slag compositions and combustion liner,and avoiding yielding big clinkers.But the diffusion of the compositions in combustion liners increases the porosity and decreases the mechanical intensity of combustion liner,and makes the slag encroachment to the liner become more serious.

  13. Combustion of low grade fractions of Lubnica coal in fluidized bed

    Directory of Open Access Journals (Sweden)

    Mladenović Milica R.

    2012-01-01

    Full Text Available In this paper a method of examination of fuel suitability for fluidized bed combustion is presented. The research of combustion characteristics of low grade fractions of Lubnica brown coal in the fluidized bed by the aforementioned methodology has been carried out on a laboratory semi-industrial apparatus of 200 kWt. Description of the experimental fluidized bed combustion facility is given, as well as experimental results, with the focus on furnace temperature distribution, in order to determine the location of the zone of intensive combustion. Based on investigation results, which are focused on combustion quality (combustion completion as well as on satisfying the environmental protection criteria, it can be stated that the investigated coal is suitable for burning in bubbling, as well as in circulating fluidized bed.

  14. Clean coal technology: gasification of South African coals - IFSA 2008

    CSIR Research Space (South Africa)

    Engelbrecht, AD

    2008-11-01

    Full Text Available Electricity demand in South Africa is increasing at a rate of 1000 MW per year. Whilst there is increasing pressure to adopt non-fossil fuel electricity generating technologies, the abundant reserves and low cost of coal make it the preferred energy...

  15. Prediction of combustion behavior of coal blends in industrial scale boilers from laboratory scale data

    Energy Technology Data Exchange (ETDEWEB)

    Pisupati, S.V.; Scaroni, A.W. [Pennsylvania State Univ., University Park, PA (United States). Coal Utilization Lab.

    1997-12-31

    Thermal analytical techniques such as thermogravimetric analysis (TGA) have been used extensively in characterizing the thermal behavior of coals. Studies have shown that burning profiles are useful for evaluating laboratory scale combustion characteristics. Blending of coals is common in the utility industry to meet emission regulations and lower fuel costs. In this paper, it is shown that using burning profiles to predict carbon burnout of individual coals and blends in a practical combustor is appropriate. (orig.)

  16. The development of coal-based technologies for Department of Defense Facilities. Interim report, March 27, 1993--July 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Miller, B.G.; Morrison, J.L.; Sharifi, R. [Pennsylvania State Univ., University Park, PA (United States). Energy and Fuels Research Center] [and others

    1993-09-24

    The US Department of Defense (DOD), through an Interagency Agreement with the US Department of Energy (DOE), has initiated a three-phase program with the Consortium for Coal-Water Slurry Fuel Technology, with the aim of decreasing DOD`s reliance on imported oil by increasing its use of coal. The program is being conducted as a cooperative agreement between the Consortium and DOE and the first phase of the program is underway. Phase I activities are focused on developing clean, coal-based combustion technologies for the utilization of both micronized coal-water slurry fuels (MCWSFs) and dry, micronized coal (DMC) in fuel oil-designed industrial boilers. Phase II research and development activities will continue to focus on industrial boiler retrofit technologies by addressing emissions control and precombustion (i.e., slagging combustion and/or gasification) strategies for the utilization of high ash, high sulfur coals. Phase III activities will examine coal-based fuel combustion systems that cofire wastes. Each phase includes an engineering cost analysis and technology assessment. The activities and status of Phase I are described below. The objective in Phase I is to deliver fully engineered retrofit options for a fuel oil-designed watertube boiler located on a DOD installation to fire either MCWSF or DMC. This will be achieved through a program consisting of the following five tasks: (1) Coal Beneficiation and Preparation; (2) Combustion Performance Evaluation; (3) Engineering Design; (4) Engineering and Economic Analysis; and (5) Final Report/Submission of Design Package.

  17. Investigation on Pulverized Coal Combustion Behavior by Non-Isothermic Integral Thermogravimetry Method

    Institute of Scientific and Technical Information of China (English)

    QI Cheng-lin; ZHANG Jian-liang; LIN Xiang-hai; LIU Qin-yuan; WANG Xiao-liu

    2011-01-01

    The combustion process of pulverized coal was investigated by non-isothermic integral thermogravimetry. The thermogravimetry curves were fitted by the Coats-Redferm approximation function, and kinetic parameters and characteristic temperatures were obtained. The optimal mixing ratio and particle size can be ascertained. The characteristic temperature of pulverized coal can be obtained from the thermogravimetry curve, and the combustion of coal can be divided into homogeneous and heterogeneous combustion according to the differential thermal analysis curve. The activation energy of a single type of coal ranking from low to high is as follows: bituminous coal, meager-lean coal, and anthracite. In the first mixing method, with more low-price meager-lean coal B replacing high price anthracite A, the activation energy slightly decreases; with more bituminous coal replacing meager-lean coal, total tendency makes a declining of activation. In the later mixing method, with an increase in particle size, a declining activation energy can be seen in total tendency.

  18. A study of oxy-coal combustion with steam addition and biomass blending by thermogravimetric analysis

    OpenAIRE

    Gil Matellanes, María Victoria; Riaza Benito, Juan; Álvarez González, Lucía; Pevida García, Covadonga; Pis Martínez, José Juan; Rubiera González, Fernando

    2011-01-01

    The thermal characteristics of pulverized coal have been studied under oxy-fuel combustion conditions using non-isothermal thermogravimetric analysis (TG). The atmospheres used were 21%O2/79%N2, 21%O2/79%CO2, 30%O2/70%O2, and 35%O2/65%CO2. Coal blends of coal with 10 and 20% of biomass were also studied under these atmospheres. The addition of 10 and 20% of steam was evaluated for the oxy-fuel combustion atmospheres with 21 and 30% of O2 in order to study the effect of the wet recirculation o...

  19. Numerical Simulation of NOx Formation in Coal Combustion with Inlet Natural Gas Burning

    Institute of Scientific and Technical Information of China (English)

    张宇; 周力行; 魏小林; 盛宏至

    2005-01-01

    A full two-fluid model of reacting gas-particle flows and coal combustion is used to simulate coal combustion with and without inlet natural gas added in the inlet. The simulation results for the case without natural gas burning is in fair agreement with the experimental results reported in references. The simulation results of different natural gas adding positions indicate that the natural gas burning can form lean oxygen combustion enviroment at the combustor inlet region and the NOx concentration is reduced. The same result can be obtained from chemical equilibrium analysis.

  20. Applied coal petrology: the role of petrology in coal utilization

    Energy Technology Data Exchange (ETDEWEB)

    Isabel Suarez-Ruiz; John Crelling [Instituto Nacional del Carbon (INCAR-CSIC), Oviedo (Spain)

    2008-08-15

    This book is an integrated approach towards the applications of coal (organic) petrology and discusses the role of this science in the field of coal and coal-related topics. Contents are: Introduction 2. Basic factors controlling coal quality and technological behaviour of coal 3. Mining and benefication 4. Coal combustion 5. Coal gasification 6. Coal liquefaction 7. Coal carbonisation 8. Coal-derived carbons 9. Coal as a Petroleum source rock and reservoir rock 10. Environmental and health aspects 11. Other applications of coal petrology.

  1. Computer simulation of an advanced combustor for clean coal technology

    Energy Technology Data Exchange (ETDEWEB)

    Chang, S.L.; Lottes, S.A.

    1992-01-01

    Magnetohydrodynamic (MHD) power generation is a clean coal technology because of its higher thermal efficiency and lower pollutant emission. Argonne National Laboratory used a comprehensive integral combustion computer code to aid the development of a TRW's second stage combustor for MHD power generation. The integral combustion code is a computer code for two-phase, two-dimensional, steady state, turbulent, and reacting flows, based on mass, momentum, and energy conservation laws for multiple gas species and solid particles of variable sizes. In the MHD second stage combustor, opposed jets of oxidizer are injected into a confined cross-stream coal gas flow laden with seed particles. The performance of the downstream MHD power generation channel depends mainly on the degree and the uniformity of gas ionization, which, in turn, depends on the uniformity of temperature and seed vapor distributions leaving the combustor. The simulation provides in-depth information of flow, combustion, and heat transfer patterns in the combustor, which is used to predict ranges of combustor operating conditions for optimum performance of the MHD system.

  2. Computer simulation of an advanced combustor for clean coal technology

    Energy Technology Data Exchange (ETDEWEB)

    Chang, S.L.; Lottes, S.A.

    1992-09-01

    Magnetohydrodynamic (MHD) power generation is a clean coal technology because of its higher thermal efficiency and lower pollutant emission. Argonne National Laboratory used a comprehensive integral combustion computer code to aid the development of a TRW`s second stage combustor for MHD power generation. The integral combustion code is a computer code for two-phase, two-dimensional, steady state, turbulent, and reacting flows, based on mass, momentum, and energy conservation laws for multiple gas species and solid particles of variable sizes. In the MHD second stage combustor, opposed jets of oxidizer are injected into a confined cross-stream coal gas flow laden with seed particles. The performance of the downstream MHD power generation channel depends mainly on the degree and the uniformity of gas ionization, which, in turn, depends on the uniformity of temperature and seed vapor distributions leaving the combustor. The simulation provides in-depth information of flow, combustion, and heat transfer patterns in the combustor, which is used to predict ranges of combustor operating conditions for optimum performance of the MHD system.

  3. Application of Foam-gel Technique to Control CO Exposure Generated During Spontaneous Combustion of Coal in Coal Mines.

    Science.gov (United States)

    Ren, Xing W; Wang, Feng Z; Guo, Qing; Zuo, Zhao B; Fang, Qi S

    2015-01-01

    In China, 47.3% of state-owned coal mines are located in coal seams that are prone to spontaneous combustion. The spontaneous combustion of coal is the main cause of the generation of a large amount of carbon monoxide, which can cause serious health issues to miners. A new technique using foam-gel formation was developed to effectively control the spontaneous combustion of coal. The gel can capture more than 90% of the water in the grout and at the same time the foam can cover dangerous areas in the goaf by stacking and cooling of foam in all directions. In this study, a mechanism of foam-gel formation was introduced and the optimal proportions of additives were defined based on experiments of different foaming properties, gelling time and water loss rate as the main index parameters. The results of a field application in a coal mine promise that this new technique would effectively prevent coal oxidation in the goaf and reduce the generation of carbon monoxide.

  4. Experimental study on performance that carbon dioxide inhibits coal oxidation and spontaneous combustion

    Institute of Scientific and Technical Information of China (English)

    DENG Jun; LI Shi-rong; ZHANG Yan-ni; MU Ying; ZHANG Yang

    2011-01-01

    Adopting oil-bath temperature programming experiment and gas chromatography,CO2's inhibitory performance on spontaneous combustion of Tingnan Coal Mine sample was analyzed.Through temperature rise rate test experiment,the accuracy,stability and reliability of the improved oil-bath temperature programming system applied in this experiment was proved to be superior to the traditional system.Spontaneous combustion characters parameters test of coal sample in pure air was carried out with this system and offered comparison standard for research in next stage.Temperature programming to coal sample was further conducted in oil-bath with different concentration of CO2.Testing results are compared with parameters of concentration of CO,O2,temperature,CO generation rate and O2 consumption rate tested and calculated in previous experiment in pure air.Methods of proportioning between concentration of CO and O2,CO concentration and temperature,CO generation rate and O2 consumption rate were applied to eliminate obstructions from certain external factors such as inlet of CO2; meanwhile influences of CO2 of different concentrations to coal oxidation and spontaneous combustion were investigated.Also CO2 inhibition technique was used in spontaneous combustion prevention in workface No.106 of Tingnan Coal Mine,data collected from which indicate that CO2 performs well in inhibiting coal oxidation and spontaneous combustion.

  5. Appalachian clean coal technology consortium

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, R.-H.; Basim, B.; Luttrell, G.H.; Phillips, D.I. [Virginia Polytechnic Inst., Blacksburg, VA (United States); Jiang, D.; Tao, D.; Parekh, B.K. [Kentucky Univ., Lexington, KY (United States); Meloy, T. [West Virginia Univ., Morgantown, WV (United States)

    1997-01-28

    Novel chemicals that can be used for increasing the efficiency of fine coal dewatering was developed at Virginia Tech. During the past quarter, Reagent A was tested on three different coal samples in laboratory vacuum filtration tests. these included flotation products from Middle Fork plant, Elkview Mining Company, and CONSOL, Inc. the tests conducted with the Middle Fork coal sample (100 mesh x 0) showed that cake moisture can be reduced by more than 10% beyond what can be achieved without using dewatering aid. This improvement was achieved at 1 lb/ton of Reagent A and 0.1 inch cake thickness. At 0. 5 inches of cake thickness, this improvement was limited to 8% at the same reagent dosage. the results obtained with the Elkview coal (28 mesh x 0) showed similar advantages in using the novel dewatering aid. Depending on the reagent dosage, cake thickness, drying cycle time and temperature, it was possible to reduce the cake moisture to 12 to 14% rage. In addition to achieving lower cake moisture, the use of Reagent A substantially decreased the cake formation time, indicating that the reagent improves the kinetics of dewatering, The test results obtained with CONSOL coal were not as good as with the other coals tested in the present work, which may be attributed to possible oxidation and/or contamination.

  6. 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

  7. Computer controlled measurement of spontaneous combustion in coal stockpiles of the Western Lignite Corporation, Turkey

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The spontaneous combustion event in coal stockpiles is inevitable when appropriate environmental conditions are available.The objective of a computerized measurement system is to measure temperature changes existing in a coal stockpile.In order to achieve this intention, the electrical signal conversion of temperatures sensed by 20 temperature sensors placed in certain points inside the coal stockpile, the transfer of these electrical signals into computer media by using analogue-digital conversion unit after applying necessary filterization and upgrading processes and the record of these information into a database in particular time intervals are provided.Afterwards, the diagrams of these time-temperature data are plotted.With the help of these graphs, the competent company will be able to examine the behavior of coal stockpiles in terms of spontaneous combustion and take necessary precautions against self-combustion beforehand.

  8. Non-linear relationship between combustion kinetic parameters and coal quality

    Institute of Scientific and Technical Information of China (English)

    Jian-guo YANG; Xiao-long ZHANG; Hong ZHAO; Li SHEN

    2012-01-01

    Combustion kinetic parameters (i.e.,activation energy and frequency factor) of coal have been proven to relate closely to coal properties; however,the quantitative relationship between them still requires further study.This paper adopts a support vector regression machine (SVR) to generate the models of the non-linear relationship between combustion kinetic parameters and coal quality.Kinetic analyses on the thermo-gravimetry (TG) data of 80 coal samples were performed to prepare training data and testing data for the SVR.The models developed were used in the estimation of the combustion kinetic parameters of ten testing samples.The predicted results showed that the root mean square errors (RMSEs) were 2.571 for the activation energy and 0.565for the frequency factor in logarithmic form,respectively.TG curves defined by predicted kinetic parameters were fitted to the experimental data with a high degree of precision.

  9. Exploitation of coal residues by their fluidized bed combustion. Aprovechamiento de los residuos de carbon mediante su combustion en lecho fluidizado

    Energy Technology Data Exchange (ETDEWEB)

    Fuertes, A.B.; Pis, J.J.; Artos, V.; Suarez, A.; Jul, J.J.; Alvarez, F.J.; Canibano, J.G. (CSIC, Oviedo (Spain). Instituto Nacional del Carbon)

    1988-01-01

    The combustion of coal rejects from Modesta washery (HUNOSA, Asturias) was studied in a fluidized bed reactor. The influence of different operational variables (temperature, fluidizing velocity and air excess) on the process efficiency was studied. Likewise, an evaluation of pollutant emissions from the fluidized bed combustion of coal rejects was made. It was concluded that fluidized bed combustion of coal rejects with ash contents of about 70% is possible and can be carried out with a high degree of combustion efficiency and low emissions. 24 refs., 10 figs., 2 tabs.

  10. Recognition of Spontaneous Combustion in Coal Mines Based on Genetic Clustering

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Spontaneous combustion is one of the greatest disasters in coal mines. Early recognition is important because it may be a potential inducement for other coalmine accidents. However, early recognition is difficult because of the complexity of different coal mines. Fuzzy clustering has been proposed to incorporate the uncertainty of spontaneous combustion in coal mines and it can give a clear degree of classification of combustion. Because FCM clustering tends to become trapped in local minima, a new approach of fuzzy c-means clustering based on a genetic algorithm is therefore proposed. Genetic algorithm is capable of locating optimal or near optimal solutions to difficult problems. It can be applied in many fields without first obtaining detailed knowledge about correlation. It is helpful in improving the effectiveness of fuzzy clustering in detecting spontaneous combustion. The effectiveness of the method is demonstrated by means of an experiment.

  11. DEVELOPMENT OF ACTIVATED CARBONS FROM COAL COMBUSTION BY-PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    Harold H. Schobert; M. Mercedes Maroto-Valer; Zhe Lu

    2003-09-30

    The increasing role of coal as a source of energy in the 21st century will demand environmental and cost-effective strategies for the use of coal combustion by-products (CCBPs), mainly unburned carbon in fly ash. Unburned carbon is nowadays regarded as a waste product and its fate is mainly disposal, due to the present lack of efficient routes for its utilization. However, unburned carbon is a potential precursor for the production of adsorbent carbons, since it has gone through a devolatilization process while in the combustor, and therefore, only requires to be activated. Accordingly, the principal objective of this work was to characterize and utilize the unburned carbon in fly ash for the production of activated carbons. The unburned carbon samples were collected from different combustion systems, including pulverized utility boilers, a utility cyclone, a stoker, and a fluidized bed combustor. LOI (loss-on-ignition), proximate, ultimate, and petrographic analyses were conducted, and the surface areas of the samples were characterized by N2 adsorption isotherms at 77K. The LOIs of the unburned carbon samples varied between 21.79-84.52%. The proximate analyses showed that all the samples had very low moisture contents (0.17 to 3.39 wt %), while the volatile matter contents varied between 0.45 to 24.82 wt%. The elemental analyses show that all the unburned carbon samples consist mainly of carbon with very little hydrogen, nitrogen, sulfur and oxygen In addition, the potential use of unburned carbon as precursor for activated carbon (AC) was investigated. Activated carbons with specific surface area up to 1075m{sup 2}/g were produced from the unburned carbon. The porosity of the resultant activated carbons was related to the properties of the unburned carbon feedstock and the activation conditions used. It was found that not all the unburned carbon samples are equally suited for activation, and furthermore, their potential as activated carbons precursors could be

  12. Characterizing the Leaching Behavior of Coal Combustion Residues using the Leaching Environmental Assessment Framework (LEAF) to Inform Future Management Decisions

    Science.gov (United States)

    Abstract for presentation on Characterizing the Leaching Behavior of Coal Combustion Residues using the Leaching Environmental Assessment Framework (LEAF) to Inform Future Management Decisions. The abstract is attached.

  13. Coal Technology Program progress report, March 1977

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-05-01

    In the final hydrocarbonization experiment with Wyodak subbituminous coal, the coal was hydrocarbonized at 1100/sup 0/F and 300 psig in the recirculating fluidized bed. Two-dimensional pyrolysis behavior of an eastern bituminous coal (Pittsburgh seam) continues to be examined. Results to date indicate that swelling is significantly more pronounced at very low heating rates. Several activities in progress are related to inspection techniques for wear- and process-resistant coatings. Experimental investigations of fireside corrosion on tubing from a fluidized bed combustor have proceeded with metallographic examination and analyses of the scale formed during the test exposure. Methods for nondestructively determining remaining tube wall thickness and scale thickness were developed. Failure prevention and analysis work was aimed at several parts from the Solvent Refined Coal Plant in Ft. Lewis, Washington. The mechanical design of the gas-fired potassium boiler system was completed with the issue of the last four drawings. One electrical and five instrument and control drawings were completed and some fabrication work was completed. Surveys of industrial coal conversion capabilities continued with emphasis on rotating components, valves, hot gas cleanup devices, and heat recovery equipment. Process and program analysis research studies continued with work on low-Btu gasification, direct combustion, advanced power conversion, liquefaction, high-Btu gasification, in-situ gasification, and beneficiation. In the fossil energy environmental project, a first draft of a landfill assessment report was issued for review. Work continued on the Environmental Monitoring Handbook and Pipeline Gas Programmatic Assessment.

  14. Nanominerals, fullerene aggregates, and hazardous elements in coal and coal combustion-generated aerosols: An environmental and toxicological assessment.

    Science.gov (United States)

    Saikia, Jyotilima; Narzary, Bardwi; Roy, Sonali; Bordoloi, Manobjyoti; Saikia, Prasenjit; Saikia, Binoy K

    2016-12-01

    Studies on coal-derived nanoparticles as well as nano-minerals are important in the context of the human health and the environment. The coal combustion-generated aerosols also affect human health and environmental quality aspects in any coal-fired station. In this study, the feed coals and their combustion-generated aerosols from coal-fired boilers of two tea industry facilities were investigated for the presence of nanoparticles/nano minerals, fullerene aggregates, and potentially hazardous elements (PHEs). The samples were characterized by using X-ray diffraction (XRD), Time-of-flight secondary ion mass spectroscopy (TOF-SIMS), High resolution-transmission electron microscopy/energy dispersive spectroscopy (HR-TEM/EDS) and Ultra Violet-visible spectroscopy (UV-Vis) to know their extent of environmental risks to the human health when present in coals and aerosols. The feed coals contain mainly clay minerals, whilst glass fragments, spinel, quartz, and other minerals occur in lesser quantities. The PM samples contain potentially hazardous elements (PHEs) like As, Pb, Cd and Hg. Enrichment factor of the trace elements in particulate matters (PMs) was calculated to determine their sources. The aerosol samples were also found to contain nanomaterials and ultrafine particles. The fullerene aggregates along with potentially hazardous elements were also detected in the aerosol samples. The cytotoxicity studies on the coal combustion-generated PM samples show their potential risk to the human health. This detailed investigation on the inter-relationship between the feed coals and their aerosol chemistry will be useful for understanding the extent of environmental hazards and related human health risk.

  15. Combustion of Coal-Mule Briquettes / Spalanie Brykietów Z Mułu Węglowego

    Science.gov (United States)

    Kijo-Kleczkowska, Agnieszka

    2013-09-01

    Combustion technologies coal-mule fuels create a number of new possibilities for organising combustion processes so that they fulfil contemporary requirements (e.g., in terms of the environment protection- related issues). The paper describes the problems of coal-mule fuel combustion that have acquired a wider significance as the quality requirements of coal combustion in power plants have been growing. Coal mines that want to fulfill expectations of power industry workers have been forced to develop and modernize plants of coal wet cleaning. It all results in the growing amount of waste arising in the process of coal wet cleaning which contains smaller and smaller coal undersizes. In this situation the concept of direct combustion of the above mentioned waste and their co-combustion with other fuels, coal and biomass, seems to be attractive. Biomass is one from the most promising sources of renewable energy. The main aim of the paper is to identify the mechanism and kinetics of combustion of coal-mule fuels and their co- -combustion with coal and biomass in the briquettes form based on extensive experimental research in air. Niekorzystny bilans paliwowy naszego kraju powoduje nadmierne obciążenie środowiska, wywołane emisją CO2, NOx, SO2 i pyłów, a także powiększeniem powierzchni koniecznych na składowanie wciąż narastających stałych odpadów paleniskowych. Górnictwo, od którego energetyka oczekuje coraz lepszego paliwa, musi stosować głębsze wzbogacanie węgla. Powoduje to ciągłą produkcję odpadów w postaci mułów poflotacyjnych. Najlepszą metodą utylizacji tych mułów jest ich spalanie w postaci zawiesin, a także ich współspalanie z innymi paliwami, węglem czy biomasą. Biomasa jest bowiem jednym z najbardziej obiecujących źródeł OZE, a jej współspalanie z paliwami węglowymi znajduje w ostatnich latach coraz szersze zastosowanie zarówno w kraju, jak i na świecie. W tej sytuacji istotne jest prowadzenie badań naukowych

  16. Environmental control implications of generating electric power from coal. 1977 technology status report. Appendix A, Part 1. Coal preparation and cleaning assessment study

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-12-01

    This report evaluates the state of the art and effectiveness of physical coal cleaning as a potential strategy for controlling SO/sub x/ emissions in coal fired power generation. Coal properties which are significantly altered by physical coal cleaning were determined. The effects of the changes in properties as they relate to pulverized coal firing, fluidized bed combustion and low Btu gasification for combined cycle powered generation were studied. Available coal washability data were integrated by computer with U.S. coal reserve data. Approximately 18% of the demonstrated coal reserve were matched with washability data. Integrated data appear in the Appendix. Current coal preparation practices were reviewed. Future trends were determined. Five process flow sheets representing increasing levels of cleaning sophistication were prepared. The clean product from each flow sheet will meet U.S. EPA New Source Performance Standards. Capital and operating costs for each case were estimated. Environmental control technology and environmental impact associated with current coal preparation and cleaning operations were assessed. Physical coal cleaning is widely practiced today. Where applicable it represents the least expensive method of coal sulfur reduction. Developmental physical and chemical coal cleaning processes were studied. The chemical methods have the advantage of being able to remove both pyritic sulfur and organic sulfur present in the coal matrix. Further R and D efforts will be required before commercialization of these processes.

  17. Preliminary study of trace element emissions and control during coal combustion

    Institute of Scientific and Technical Information of China (English)

    ZHANG Junying; ZHAO Yongchun; DING Feng; ZENG Hancai; ZHENG Chuguang

    2007-01-01

    Hazardous trace element emissions have caused serious harm to human health in China.Several typical high-toxic trace element coals were collected from different districts and were used to investigate the emission characteristics of toxic trace elements (As,Se,Cr,Hg) and to explore preliminary control methods.Coal combustion tests were conducted in several bench-scale furnaces including drop tube furnace (DTF),circulating fluidized bed (CFB) combustion furnace,and fixed-bed combustion furnace.Calcium oxide was used to control the emission of arsenic and selenium.The granular activated carbons (AC) and activatedcarbon fibers (ACF) were used to remove mercury in the flue gas from coal combustion.The chemical composition and trace element contents of ash and particulate matter (PM)were determined by X-ray fluorescence (XRF) spectrometry and inductively coupled plasma-atomic emission spectrometry (ICP-AES),respectively.The speciation and concentration of mercury were investigated using the Ontario-Hydro method.X-ray diffraction spectrometry (XRD) was used to determine the mineral composition of production during combustion experiments.With the addition of a calciumbased sorbent,arsenic concentration in PM1 sharply decreased from 0.25-0.11 mg/m3.In fixed-bed combustion of coal,the retention rates of selenium volatiles were between 11.6% and 50.7% using lime.In the circulating fluidized-bed combustion of coal,the content of selenium in ash from the chimney was reduced to one-fourth of its original value and that in leaching water from the chimney decreased by two orders of magnitude using lime.Calcium-based sorbent is an effective additive to control the emission of As and Se during coal combustion.The emission of chromium is influenced by the occurrence mode of Cr in coal.Chromium emission in PM2.5 during coal combustion is 55.5 and 34.7 μg/m3 for Shenbei coal and mixed Pingdingshan coal,respectively.The adsorptive capacity of granular activated carbon for Hg0 is

  18. Air toxic emissions from the combustion of coal: Identifying and quantifying hazardous air pollutants from US coals

    Energy Technology Data Exchange (ETDEWEB)

    Szpunar, C.B.

    1992-09-01

    This report addresses the key air toxic emissions likely to emanate from continued and expanded use of domestic coal. It identifies and quantifies those trace elements specified in the US 1990 Clean Air Act Amendments, by tabulating selected characterization data on various source coals by region, state, and rank. On the basis of measurements by various researchers, this report also identifies those organic compounds likely to be derived from the coal combustion process (although their formation is highly dependent on specific boiler configurations and operating conditions).

  19. Development of coal store and transportation technology using horizontal coal bunker

    Institute of Scientific and Technical Information of China (English)

    TIAN Jian-sheng; CHEN Qing-shu

    2005-01-01

    Discussed the necessity of setting up the coal bunker in mining, introduced the development of coal bunker technology, combining the mining characteristic of the high yield and high-efficient working face in China at present, and point out that the type of horizontal coal bunker, is a kind of security, high-efficient coal store and transportation technology of suiting the modern production need of the colliery, is the developing direction of technology of store and transportation of coal bunker.

  20. Underground coal gasification technology impact on coal reserves in Colombia

    Directory of Open Access Journals (Sweden)

    John William Rosso Murillo

    2013-12-01

    Full Text Available In situ coal gasification technology (Underground Coal Gasification–UCG– is an alternative to the traditional exploitation, due to it allows to reach the today’s inaccessible coal reserves’ recovery, to conventional mining technologies. In this article I answer the question on how the today’s reserves available volume, can be increased, given the possibility to exploit further and better the same resources. Mining is an important wealth resource in Colombia as a contributor to the national GDP. According with the Energy Ministry (Ministerio de Minas y Energía [1] mining has been around 5% of total GDP in the last years. This is a significant fact due to the existence of a considerable volume of reserves not accounted for (proved reserves at year 2010 were 6.700 million of tons. Source: INGEOMINAS and UPME, and the coal future role’s prospect, in the world energy production.

  1. Energy recycling by co-combustion of coal and recovered paint solids from automobile paint operations.

    Science.gov (United States)

    Suriyawong, Achariya; Magee, Rogan; Peebles, Ken; Biswas, Pratim

    2009-05-01

    During the past decade, there has been substantial interest in recovering energy from many unwanted byproducts from industries and municipalities. Co-combustion of these products with coal seems to be the most cost-effective approach. The combustion process typically results in emissions of pollutants, especially fine particles and trace elements. This paper presents the results of an experimental study of particulate emission and the fate of 13 trace elements (arsenic [As], barium [Ba], cadmium [Cd], chromium [Cr], copper [Cu], cobalt [Co], manganese [Mn], molybdenum [Mo], nickel [Ni], lead [Pb], mercury [Hg], vanadium [V], and zinc [Zn]) during combustion tests of recovered paint solids (RPS) and coal. The emissions from combustions of coal or RPS alone were compared with those of co-combustion of RPS with subbituminous coal. The distribution/partitioning of these toxic elements between a coarse-mode ash (particle diameter [dp] > 0.5 microm), a submicrometer-mode ash (dp burning particles and the higher volatile chlorine species. Hg was completely volatilized in all cases; however, the fraction in the oxidized state increased with co-combustion. Most trace elements, except Zn, were retained in ash during combustion of RPS alone. Mo was mostly retained in all samples. The behavior of elements, except Mn and Mo, varied depending on the fuel samples. As, Ba, Cr, Co, Cu, and Pb were vaporized to a greater extent from cocombustion of RPS and coal than from combustion of either fuel. Evidence of the enrichment of certain toxic elements in submicrometer particles has also been observed for As, Cd, Cr, Cu, and Ni during co-combustion.

  2. Combustion and emissions characterization of pelletized coal fuels. [Quarterly] technical report, March 1--May 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Rajan, S. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mechanical Engineering and Energy Processes

    1993-09-01

    Pelletization of coal offers a means of utilizing coal fines which otherwise would be difficult to use. Other advantages of coal pelletization include: (a) utilization of low grade fuels such as preparation plant waste, (b) impregnation of pellets with calcium carbonate or calcium hydroxide sorbent for efficient sulfur removal, and (c) utilization of coal fines of low quality in combination with different types of binders. The objective of this project is to investigate the carbon conversion efficiency and SO{sub 2} and NO{sub x} emissions from combusting pelletized coal fuels made from preparation plant waste streams using both limestone and calcium hydroxide as sorbent and cornstarch and gasification tar as binders. The combustion performance of these pelletized fuels is compared with equivalent data from a reference run-of-mine coal. Six different samples of coal pellets have been secured from ISGS researchers. Combustion and emissions characterization of these pellets in the laboratory scale 4-inch diameter circulating fluidized bed have been performed on some of the pellet samples. The pellets burn readily, and provide good bed temperature control. Preliminary results show good carbon conversion efficiencies. Oxides of nitrogen emissions are quite low and sulfur dioxide emissions are as good as or lower than those from a representative run-of-mine coal.

  3. Prevention of trace and major element leaching from coal combustion products by hydrothermally-treated coal ash

    Energy Technology Data Exchange (ETDEWEB)

    Adnadjevic, B.; Popovic, A.; Mikasinovic, B. [University of Belgrade, Belgrade (Serbia). Dept. of Chemistry

    2009-07-01

    The most important structural components of coal ash obtained by coal combustion in 'Nikola Tesla A' power plant located near Belgrade (Serbia) are amorphous alumosilicate, alpha-quartz, and mullite. The phase composition of coal ash can be altered to obtain zeolite type NaA that crystallizes in a narrow crystallization field (SiO{sub 2}/Al{sub 2}O{sub 3}; Na{sub 2}O/SiO{sub 2}; H{sub 2}O/Na{sub 2}O ratios). Basic properties (crystallization degree, chemical composition, the energy of activation) of obtained zeolites were established. Coal ash extracts treated with obtained ion-exchange material showed that zeolites obtained from coal ash were able to reduce the amounts of iron, chromium, nickel, zinc, copper, lead, and manganese in ash extracts, thus proving its potential in preventing pollution from dump effluent waters.

  4. THE DEVELOPMENT OF COAL-BASED TECHNOLOGIES FOR DEPARTMENT OF DEFENSE FACILITIES

    Energy Technology Data Exchange (ETDEWEB)

    Bruce G. Miller; Sharon Falcone Miller; Sarma V. Pisupati; Chunshan Song; Ronald S. Wasco; Ronald T. Wincek; Xiaochun Xu; Alan W. Scaroni; Richard Hogg; Subhash Chander; M. Thaddeus Ityokumbul; Mark S. Klima; Peter T. Luckie; Adam Rose; Richard L. Gordon; Jeffrey Lazo; A. Michael Schaal

    2004-01-30

    The third phase of a three-phase project investigating the development of coal-based technologies for US Department of Defense (DOD) facilities was completed. The objectives of the project were to: decrease DOD's dependence on foreign oil and increase its use of coal; promote public and private sector deployment of technologies for utilizing coal-based fuels in oil-designed combustion equipment; and provide a continuing environment for research and development of coal-based fuel technologies for small-scale applications at a time when market conditions in the US are not favorable for the introduction of coal-fired equipment in the commercial and industrial capacity ranges. The Phase III activities were focused on evaluating deeply-cleaned coals as fuels for industrial boilers and investigating emissions control strategies for providing ultra-low emissions when firing coal-based fuels. This was addressed by performing coal beneficiation and preparation studies, and bench- to demonstration-scale emissions reduction studies. In addition, economic studies were conducted focused on determining cost and market penetration, selection of incentives, and regional economic impacts of coal-based technologies.

  5. Co-combustion of coal and sewage sludge: chemical and ecotoxicological properties of ashes.

    Science.gov (United States)

    Barbosa, Rui; Lapa, Nuno; Boavida, Dulce; Lopes, Helena; Gulyurtlu, Ibrahim; Mendes, Benilde

    2009-10-30

    The co-combustion of sewage sludge (SS) and coal is widely used for the treatment and thermal valorization of SS produced in wastewater treatment plants. The chemical and ecotoxicological properties of the ashes produced in this thermal treatment have not been fully studied. Two combustion tests were performed in a fluidized bed combustor. Colombian coal was used as fuel in test A. A blend (1+1) of this coal and a stabilized SS (Biogran) was used in a second test B. Samples of the bottom and fly ashes trapped in two sequential cyclones were collected. The characterization of the ashes was focused on two main aspects: (1) the bulk content of a set of metals and (2) the characterization of eluates produced according to the European Standard leaching test EN 12457-2. The eluates were submitted to an ecotoxicological characterization for two bio-indicators. In what concerns the bulk content of ashes, both combustion tests have produced ashes with different compositions. The ashes formed during the co-combustion test have shown higher concentrations of metals, namely Cr, Cu, Ni, Pb, Zn and Fe for all ashes. The leaching test has shown low mobility of these elements from the by-products produced during the combustion and co-combustion tests. Cr and Cr(VI) were mainly detected in the eluates of the 1st cyclone ashes produced in both combustion tests and in the 2nd cyclone ashes produced in the co-combustion test. Considering the ecotoxicity assays, the eluates of bottom and fly ashes for both combustion and co-combustion tests have shown low ecotoxic levels. The micro-crustacean Daphnia magna was generally more sensitive than the bacterium Vibrio fischeri. CEMWE criterion has allowed to classify the bottom ashes for both combustion and co-combustion tests as non-toxic residues and the fly ashes collected in both cyclones as toxic.

  6. Industrial Combustion Technology Roadmap. A Technology Roadmap by and for the Industrial Combustion Community

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2002-10-01

    The U.S. combustion industry is among the most productive, efficient, and technologically sophisticated in the world and remains vital to the nation’s economic competitiveness and national security. As the industry looks forward, it confronts tremendous growth opportunities but also significant technical and market challenges. Future industry success will depend on the industry's ability to respond to competitive pressures as well as public expectations for a clean and sustainable industry. Much progress has been made in understanding the fundamental science of combustion; however, much more is needed as regulatory and competitive forces push the industry to develop combustion equipment with better performance, lower environmental impact, and greater flexibility. Immense opportunities exist for companies to develop and apply new technology responding to these needs. Unfortunately, few companies can accept the high technical and financial risk required for the research if the technology is not adopted widely enough to provide a payback on their investment.

  7. Zinc isotopic composition of particulate matter generated during the combustion of coal and coal + tire-derived fuels.

    Science.gov (United States)

    Borrok, David M; Gieré, Reto; Ren, Minghua; Landa, Edward R

    2010-12-01

    Atmospheric Zn emissions from the burning of coal and tire-derived fuel (TDF) for power generation can be considerable. In an effort to lay the foundation for tracking these contributions, we evaluated the Zn isotopes of coal, a mixture of 95 wt % coal + 5 wt % TDF, and the particulate matter (PM) derived from their combustion in a power-generating plant. The average Zn concentrations and δ(66)Zn were 36 mg/kg and 183 mg/kg and +0.24‰ and +0.13‰ for the coal and coal + TDF, respectively. The δ(66)Zn of the PM sequestered in the cyclone-type mechanical separator was the lightest measured, -0.48‰ for coal and -0.81‰ for coal+TDF. The δ(66)Zn of the PM from the electrostatic precipitator showed a slight enrichment in the heavier Zn isotopes relative to the starting material. PM collected from the stack had the heaviest δ(66)Zn in the system, +0.63‰ and +0.50‰ for the coal and coal + TDF, respectively. Initial fractionation during the generation of a Zn-rich vapor is followed by temperature-dependent fractionation as Zn condenses onto the PM. The isotopic changes of the two fuel types are similar, suggesting that their inherent chemical differences have only a secondary impact on the isotopic fractionation process.

  8. 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.

  9. Industrial Combustion Technology Roadmap: A Technology Roadmap by and for the Industrial Combustion Community (2002)

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2002-10-01

    The Industrial Technology Program (ITP) convened industry workshops in 2001 to update the 1999 roadmap. The revised plan, in which the combustion industry lays out the R&D initiatives to meet its performance targets for the next 20 years, is presented in the Industrial Combustion Technology Roadmap. This roadmap showcases a comprehensive R&D plan for the industry and specifies the coordination and alignment of key groups, such as industry, academia, and the federal government, to meet the future energy and environmental goals of the industry.

  10. Development of low rank coals upgrading and their CWM producing technology; Teihin`itan kaishitsu ni yoru CWM seizo gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Sugiyama, T. [Center for Coal Utilization, Japan, Tokyo (Japan); Tsurui, M.; Suto, Y.; Asakura, M. [JGC Corp., Tokyo (Japan); Ogawa, J.; Yui, M.; Takano, S. [Japan COM Co. Ltd., Japan, Tokyo (Japan)

    1996-09-01

    A CWM manufacturing technology was developed by means of upgrading low rank coals. Even though some low rank coals have such advantages as low ash, low sulfur and high volatile matter content, many of them are merely used on a small scale in areas near the mine-mouths because of high moisture content, low calorification and high ignitability. Therefore, discussions were given on a coal fuel manufacturing technology by which coal will be irreversibly dehydrated with as much volatile matters as possible remaining in the coal, and the coal is made high-concentration CWM, thus the coal can be safely transported and stored. The technology uses a method to treat coal with hot water under high pressure and dry it with hot water. The method performs not only removal of water, but also irreversible dehydration without losing volatile matters by decomposing hydrophilic groups on surface and blocking micro pores with volatile matters in the coal (wax and tar). The upgrading effect was verified by processing coals in a pilot plant, which derived greater calorification and higher concentration CWM than with the conventional processes. A CWM combustion test proved lower NOx, lower SOx and higher combustion rate than for bituminous coal. The ash content was also found lower. This process suits a Texaco-type gasification furnace. For a production scale of three million tons a year, the production cost is lower by 2 yen per 10 {sup 3} kcal than for heavy oil with the same sulfur content. 11 figs., 15 tabs.

  11. The Clean Coal Technology Program: Lessons learned

    Energy Technology Data Exchange (ETDEWEB)

    1994-07-01

    The Clean Coal Technology (CCT) Program is a unique partnership between the federal government and industry that has as its primary goal the successful introduction of new clean coal utilization technologies into the energy marketplace. Clean coal technologies being demonstrated under the CCT Program are establishing a technology base that will enable the nation to meet more stringent energy and environmental goals. Most of the, demonstrations are being conducted at commercial scale, in actual user environments, and under circumstances typical of commercial operations. These features allow the potential of the technologies to be evaluated in their intended commercial applications. Each application addresses one of the following four market sectors: advanced electric power generation; environmental control devices; coal processing for clean fuels; and industrial applications. The purpose of this report is fourfold: Explain the CCT program as a model for successful joint government industry partnership for selecting and demonstrating technologies that have promise for adaptation to the energy marketplace; set forth the process by which the process has been implemented and the changes that have been made to improve that process; outline efforts employed to inform potential users and other interested parties about the technologies being developed; and examine some of the questions which must be considered in determining if the CCT Program model can be applied to other programs.

  12. Atmospheric fluidized-bed combustion (AFBC) co-firing of coal and hospital waste. Environmental Assessment

    Energy Technology Data Exchange (ETDEWEB)

    1993-02-01

    The proposed project involves co-firing of coal and medical waste (including infectious medical waste) in an atmospheric fluidized-bed combustor (AFBC) to safely dispose of medical waste and produce steam for hospital needs. Combustion at the design temperature and residence time (duration) in the AFBC has been proven to render infectious medical waste free of disease producing organisms. The project would be located at the Veterans Affairs (VA) Medical Center in Lebanon, Pennsylvania. The estimated cost of the proposed AFBC facility is nearly $4 million. It would be jointly funded by DOE, Veterans Affairs, and Donlee Technologies, Inc., of York, Pennsylvania, under a cooperative agreement between DOE and Donlee. Under the terms of this agreement, $3.708 million in cost-shared financial assistance would be jointly provided by DOE and the Veterans Affairs (50/50), with $278,000 provided by Donlee. The purposes of the proposed project are to: (1) provide the VA Medical Center and the Good Samaritan Hospital (GSH), also of Lebanon, Pennsylvania, with a solution for disposal of their medical waste; and (2) demonstrate that a new coal-burning technology can safely incinerate infectious medical waste, produce steam to meet hospital needs, and comply with environmental regulations.

  13. Combustion characteristics of Malaysian oil palm biomass, sub-bituminous coal and their respective blends via thermogravimetric analysis (TGA).

    Science.gov (United States)

    Idris, Siti Shawalliah; Rahman, Norazah Abd; Ismail, Khudzir

    2012-11-01

    The combustion characteristics of Malaysia oil palm biomass (palm kernel shell (PKS), palm mesocarp fibre (PMF) and empty fruit bunches (EFB)), sub-bituminous coal (Mukah Balingian) and coal/biomass blends via thermogravimetric analysis (TGA) were investigated. Six weight ratios of coal/biomass blends were prepared and oxidised under dynamic conditions from temperature 25 to 1100°C at four heating rates. The thermogravimetric analysis demonstrated that the EFB and PKS evolved additional peak besides drying, devolatilisation and char oxidation steps during combustion. Ignition and burn out temperatures of blends were improved in comparison to coal. No interactions were observed between the coal and biomass during combustion. The apparent activation energy during this process was evaluated using iso-conversional model free kinetics which resulted in highest activation energy during combustion of PKS followed by PMF, EFB and MB coal. Blending oil palm biomass with coal reduces the apparent activation energy value.

  14. Multifunctional (NOx/CO/O2) Solid-State Sensors For Coal Combustion Control

    Energy Technology Data Exchange (ETDEWEB)

    Eric D. Wachsman

    2006-12-31

    Solid-state sensors were developed for coal combustion control and the understanding of sensing mechanisms was advanced. Several semiconducting metal oxides (p-type and n-type) were used to fabricate sensor electrodes. The adsorption/desorption characteristics and catalytic activities of these materials were measured with Temperature Programmed Desorption (TPD) and Temperature Programmed Reaction (TPR) experiments. The sensitivity, selectivity, and response time of these sensors were measured for steps of NO, NO{sub 2}, CO, CO{sub 2}, O{sub 2}, and H{sub 2}O vapor in simple N{sub 2}-balanced and multi-component, simulated combustion-exhaust streams. The role of electrode microstructure and fabrication parameters on sensing performance was investigated. Proof for the proposed sensing mechanism, Differential Electrode Equilibria, was demonstrated by relating the sensing behavior (sensitivities and cross-sensitivities) of the various electrode materials to their gas adsorption/desorption behaviors and catalytic activities. A multifunctional sensor array consisting of three sensing electrodes and an integrated heater and temperature sensors was fabricated with tape-casting and screen-printing and its NO{sub x} sensing performance was measured. The multifunctional sensor demonstrated it was possible to measure NO{sub 2} independent of NO by locally heating one of the sensing electrodes. The sensor technology was licensed to Fuel FX International, Inc. Fuel FX has obtained investor funding and is developing prototype sensors as a first step in their commercialization strategy for this technology.

  15. Burnout synergic or inhibiting effects in combustion assays of coal/sawdust blends

    Energy Technology Data Exchange (ETDEWEB)

    Ximena Garcia; Ximena Matus; Claudia Ulloa; Alfredo L. Gordon [University of Concepcion, Concepcion (Chile). Dept. of Chemical Engineering

    2007-07-01

    Characterization of chars and charcoal and combustion assays of coal/ pine sawdust blends were carried on to evaluate the burnout, under conditions similar to those found in pulverized coal combustion. A drop tube furnace (DTF) was used to generate chars from three coals of different rank (Bitsch, a lignite; Lemington, a bituminous HV coal; and LD, a semianthracite) and charcoal from sawdust (S). Burning profiles, as well as morphological and optical characterization of these chars were obtained and discussed. Pulverized samples of pure constituents and sawdust/coal blends (5, 10 and 20%wt of S) were burned in the DTF reactor. Samples of combustion residues were collected for characterization. Depending on blend composition and the rank of the coal being blended, positive and negative deviations with respect to the expected weighted average value of the burnout were measured. This behavior is related both, to the duration of the step by which simultaneous burning of char and charcoal take place, and to the sawdust content in the blend. The optical analysis of combustion residues supports this conclusion. 7 refs., 6 figs., 3 tabs.

  16. An important missing source of atmospheric carbonyl sulfide: Domestic coal combustion

    Science.gov (United States)

    Du, Qianqian; Zhang, Chenglong; Mu, Yujing; Cheng, Ye; Zhang, Yuanyuan; Liu, Chengtang; Song, Min; Tian, Di; Liu, Pengfei; Liu, Junfeng; Xue, Chaoyang; Ye, Can

    2016-08-01

    Carbonyl sulfide (COS), carbon monoxide (CO), and sulfur dioxide (SO2) emissions generated from prevailing domestic coal stoves fueled with raw bituminous coal were studied under alternation cycles of flaming and smoldering combustion. The measurements in the laboratory and the farmer's house indicated that COS and CO emissions mainly occurred under the condition of flame extinguishment after coal loading, whereas SO2 emissions were mainly generated through combustion with flame. The COS emission factors for the domestic stoves in the laboratory and the farmer's house were recorded as 0.57 ± 0.10 g COS kg-1 and 1.43 ± 0.32 g COS kg-1, being approximately a factor of 50 and 125 greater than that generated from coal power plants, respectively. Based on the COS emission factors measured in this study, COS emission from only domestic coal combustion in China would be at least 30.5 ± 5.6 Gg S yr-1 which was 1 magnitude greater than the current COS estimation from the total coal combustion in China.

  17. New stage of clean coal technology in Japan; Clean coal technology no aratana tenkai ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Kawaguchi, Y. [Agency of Natural Resources and Energy, Tokyo (Japan)

    1996-09-01

    The paper described the positioning and new development of clean coal technology. Coal is an important resource which supplies approximately 30% of the energy consumed in all the world. In the Asian/Pacific region, especially, a share of coal in energy is high, around 60% of the world, and it is indispensable to continue using coal which is abundantly reserved. Japan continues using coal as an important energy among petroleum substituting energies taking consideration of the global environment, and is making efforts for development and promotion of clean coal technology aiming at further reduction of environmental loads. Moreover, in the Asian region where petroleum depends greatly upon outside the region, it is extremely important for stabilization of Japan`s energy supply that coal producing countries in the region promote development/utilization of their coal resources. For this, it is a requirement for Japan to further a coal policy having an outlook of securing stable coal supply/demand in the Asian region. 6 figs., 2 tabs.

  18. Natural attenuation of coal combustion waste in river sediments.

    Science.gov (United States)

    Markwiese, James T; Rogers, William J; Carriker, Neil E; Thal, David I; Vitale, Rock J; Gruzalski, Jacob G; Rodgers, Erin E; Babyak, Carol M; Ryti, Randall T

    2014-08-01

    The weathering of coal combustion products (CCPs) in a lotic environment was assessed following the Tennessee Valley Authority (Kingston, TN) fly ash release of 2008 into surrounding rivers. Sampled materials included stockpiled ash and sediment collected from 180 to 880 days following the release. Total recoverable concentrations of heavy metals and metalloids in sediment were measured, and percent ash was estimated visually or quantified by particle counts. Arsenic and selenium in sediment were positively correlated with percent ash. For samples collected 180 days after the release, total concentrations of trace elements downstream of the release were greater than reference levels but less than concentrations measured in stockpiled ash. Total concentrations of trace elements remained elevated in ash-laden sediment after almost 2.5 years. A sequential extraction procedure (SEP) was used to speciate selected fractions of arsenic, copper, lead, nickel, and selenium in decreasing order of bioavailability. Concentrations of trace elements in sequentially extracted fractions were one to two orders of magnitude lower than total recoverable trace elements. The bulk of sequentially extractable trace elements was associated with iron-manganese oxides, the least bioavailable fraction of those measured. By 780 days, trace element concentrations in the SEP fractions approached reference concentrations in the more bioavailable water soluble, ion exchangeable, and carbonate-bound fractions. For each trace element, the percentage composition of the bioavailable fractions relative to the total concentration was calculated. These SEP indices were summed and shown to significantly decrease over time. These results document the natural attenuation of leachable trace elements in CCPs in river sediment as a result of the loss of bioavailable trace elements over time.

  19. Coal technology program. Progress report, September 1977

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-10-01

    A successful hydrocarbonization experiment at 300 psi of hydrogen and approximately 1050/sup 0/F was completed with Illinois No. 6 coal that had been chemically pretreated with aqueous CaO and NaOH. In pressurized carbonization, one successful experiment at approximately 1100/sup 0/F and 415 psi of methane was completed with vacuum distillation residue from the H-Coal process. In the thick section pressure vessel work, procedures are being developed with the DATA TRAK heat treating facility to allow preparation of relatively large heat treated samples of 2 /sup 1///sub 4/ Cr-1 Mo steel. In the Gas-Fired Potassium Boiler Project, the potassium system installation was completed, the fill and drain tank was filled with potassium, and the checkout of the instruments and controls was nearly completed. The Coal-Fired Alkali Metal Power System Design Study was completed and a draft report describing the design was issued. Cesium was selected as the working fluid for the topping cycle. For the reference design, the furnace operated at atmospheric pressure and the cycle conditions for the power conversion systems were 1500/sup 0/F (1089 K) to 900/sup 0/F (756 K) for the topping cycle and 2400 psi (16.5 MPa)/1000/sup 0/F (811 K)/1000/sup 0/F (811 K) to 1 /sup 1///sub 2/ in. Hg (5079 Pa) for the steam system. ORNL was requested by DOE to develop a program for testing coal feeders currently under development. Work was continued on process modeling, the preparation of a Synthetic Fuels Research Digest, a survey of industrial coal conversion equipment capabilities, and studies of flash hydropyrolysis, hot gas purification processes, processes for heat recovery, and hydrogen production by the steam/molten iron process. Process and program analysis studies were continued on low-Btu gasification, direct combustion, advanced power conversion systems, liquefaction, high-Btu gasification, in-situ gasification, and coal beneficiation.

  20. Annual Change Detection by ASTER TIR Data and an Estimation of the Annual Coal Loss and CO2 Emission from Coal Seams Spontaneous Combustion

    Directory of Open Access Journals (Sweden)

    Xiaomin Du

    2014-12-01

    Full Text Available Coal fires, including both underground and coal waste pile fires, result in large losses of coal resources and emit considerable amounts of greenhouse gases. To estimate the annual intensity of greenhouse gas emissions and the loss of coal resources, estimating the annual loss from fire-influenced coal seams is a feasible approach. This study assumes that the primary cause of coal volume loss is subsurface coal seam fires. The main calculation process is divided into three modules: (1 Coal fire quantity calculations, which use change detection to determine the areas of the different coal fire stages (increase/growth, maintenance/stability and decrease/shrinkage. During every change detections, the amount of coal influenced by fires for these three stages was calculated by multiplying the coal mining residual rate, combustion efficiency, average thickness and average coal intensity. (2 The life cycle estimate is based on remote sensing long-term coal fires monitoring. The life cycles for the three coal fire stages and the corresponding life cycle proportions were calculated; (3 The diurnal burnt rates for different coal fire stages were calculated using the CO2 emission rates from spontaneous combustion experiments, the coal fire life cycle, life cycle proportions. Then, using the fire-influenced quantity aggregated across the different stages, the diurnal burn rates for the different stages and the time spans between the multi-temporal image pairs used for change detection, we estimated the annual coal loss to be 44.3 × 103 tons. After correction using a CH4 emission factor, the CO2 equivalent emissions resulting from these fires was on the order of 92.7 × 103 tons. We also discovered that the centers of these coal fires migrated from deeper to shallower parts of the coal seams or traveled in the direction of the coal seam strike. This trend also agrees with the cause of the majority coal fires: spontaneous combustion of coalmine goafs.

  1. Polycyclic aromatic hydrocarbons (PAHs) from coal combustion: emissions, analysis, and toxicology.

    Science.gov (United States)

    Liu, Guijian; Niu, Zhiyuan; Van Niekerk, Daniel; Xue, Jian; Zheng, Liugen

    2008-01-01

    Coal may become more important as an energy source in the 21st century, and coal contains large quantities of organic and inorganic matter. When coal burns chemical and physical changes take place, and many toxic compounds are formed and emitted. Polycyclic aromatic hydrocarbons (PAHs) are among those compounds formed and are considered to pose potential health hazards because some PAHs are known carcinogens. Based on their toxicology, 16 PAHs are considered as priority pollutants by the USEPA. More attention must be given to the various methods of extraction and analysis of PAH from coal or coal products to accurately explain and determine the species of PAHs. The influences of the extraction time, solvents, and methods for PAH identification are important. In the future, more methods and influences will be studied more carefully and widely. PAHs are environmental pollutants, are highly lipid soluble, and can be absorbed by the lungs, gut, and skin of mammals because they are associated with fine particles from coal combustion. More attention is being given to PAHs because of their carcinogenic and mutagenic action. We suggest that when using a coal stove indoors, a chimney should be used; the particles and gas containing PAHs should be released outdoors to reduce the health hazard, especially in Southwest China. During coal utilization processes, such as coal combustion and pyrolysis, PAHs released may be divided into two categories according to their formation pathways: one pathway is derived from complex chemical reactions and the other is from free PAHs transferred from the original coal. The formation and emission of PAHs is a complex physical and chemical process that has received considerable attention in recent years. It is suggested that the formation mechanisms of PAHs will be an increasingly important topic for researchers to find methods for controlling emissions during coal combustion.

  2. Emissions from carpet combustion in a pilot-scale rotary kiln: comparison with coal and particle-board combustion.

    Science.gov (United States)

    Konopa, Stephanie Lucero; Mulholland, James A; Realff, Matthew J; Lemieux, Paul M

    2008-08-01

    The use of post-consumer carpet as a potential fuel substitute in cement kilns and other high-temperature processes is being considered to address the problem of huge volumes of carpet waste and the opportunity of waste-to-energy recovery. Carpet represents a high volume waste stream, provides high energy value, and contains other recoverable materials for the production of cement. This research studied the emission characteristics of burning 0.46-kg charges of chopped nylon carpet squares, pulverized coal, and particle-board pellets in a pilot-scale natural gas-fired rotary kiln. Carpet was tested with different amounts of water added. Emissions of oxygen, carbon dioxide, nitric oxide (NO), sulfur dioxide (SO2), carbon monoxide (CO), and total hydrocarbons and temperatures were continuously monitored. It was found that carpet burned faster and more completely than coal and particle board, with a rapid volatile release that resulted in large and variable transient emission peaks. NO emissions from carpet combustion ranged from 0.06 to 0.15 g/MJ and were inversely related to CO emissions. Carpet combustion yielded higher NO emissions than coal and particle-board combustion, consistent with its higher nitrogen content. SO2 emissions were highest for coal combustion, consistent with its higher sulfur content than carpet or particle board. Adding water to carpet slowed its burn time and reduced variability in the emission transients, reducing the CO peak but increasing NO emissions. Results of this study indicate that carpet waste can be used as an effective alternative fuel, with the caveats that it might be necessary to wet carpet or chop it finely to avoid excessive transient puff emissions due to its high volatility compared with other solid fuels, and that controlled mixing of combustion air might be used to control NO emissions from nylon carpet.

  3. MUTATION SPECTRA OF SMOKY COAL COMBUSTION EMMISSIONS IN SALMONELLA REFLECTS THE TP53 AND KRAS MUTATIONS IN LUNG TUMORS FROM SMOKY COAL EXPOSED INDIVIDUALS

    Science.gov (United States)

    Mutation Spectra of Smoky Coal Combustion Emissions in Salmonella Reflect the TP53and KRAS Mutations in Lung Tumors from Smoky Coal-Exposed Individuals Abstract Nonsmoking women in Xuan Wei County, Yunnan Province, China who use smoky coal for cooking and h...

  4. A comparison of co-combustion characteristics of coal with wood and hydrothermally treated municipal solid waste.

    Science.gov (United States)

    Muthuraman, Marisamy; Namioka, Tomoaki; Yoshikawa, Kunio

    2010-04-01

    In this work, thermogravimetric analysis was used to investigate the co-combustion characteristics of wood and municipal solid waste (MSW) with Indian coal. Combustion characteristics like volatile release, ignition were studied. Wood presented an enhanced reaction rate reflecting its high volatile and low ash contents, while MSW enhanced ignition behavior of Indian coal. The results indicate that blending of both, wood and MSW improves devolatization properties of coal. Significant interaction was detected between wood and Indian coal, and reactivity of coal has improved upon blending with wood. On the other hand, MSW shows a good interaction with Indian coal leading to significant reduction in ignition temperature of coal and this effect was more pronounced with higher blending ratio of MSW. Hence MSW blending could more positively support the combustion of low quality Indian coal as compared to wood, due to its property of enhancement of ignition characteristics.

  5. UNDERGROUNG PLACEMENT OF COAL PROCESSING WASTE AND COAL COMBUSTION BY-PRODUCTS BASED PASTE BACKFILL FOR ENHANCED MINING ECONOMICS

    Energy Technology Data Exchange (ETDEWEB)

    Y.P. Chugh; D. Biswas; D. Deb

    2002-06-01

    This project has successfully demonstrated that the extraction ratio in a room-and-pillar panel at an Illinois mine can be increased from the current value of approximately 56% to about 64%, with backfilling done from the surface upon completion of all mining activities. This was achieved without significant ground control problems due to the increased extraction ratio. The mined-out areas were backfilled from the surface with gob, coal combustion by-products (CCBs), and fine coal processing waste (FCPW)-based paste backfill containing 65%-70% solids to minimize short-term and long-term surface deformations risk. This concept has the potential to increase mine productivity, reduce mining costs, manage large volumes of CCBs beneficially, and improve the miner's health, safety, and environment. Two injection holes were drilled over the demonstration panel to inject the paste backfill. Backfilling was started on August 11, 1999 through the first borehole. About 9,293 tons of paste backfill were injected through this borehole with a maximum flow distance of 300-ft underground. On September 27, 2000, backfilling operation was resumed through the second borehole with a mixture of F ash and FBC ash. A high-speed auger mixer (new technology) was used to mix solids with water. About 6,000 tons of paste backfill were injected underground through this hole. Underground backfilling using the ''Groutnet'' flow model was simulated. Studies indicate that grout flow over 300-foot distance is possible. Approximately 13,000 tons of grout may be pumped through a single hole. The effect of backfilling on the stability of the mine workings was analyzed using SIUPANEL.3D computer program and further verified using finite element analysis techniques. Stiffness of the backfill mix is most critical for enhancing the stability of mine workings. Mine openings do not have to be completely backfilled to enhance their stability. Backfill height of about 50% of the seam

  6. Deposit Formation during Coal-Straw Co-Combustion in a Utility PF-Boiler

    DEFF Research Database (Denmark)

    Andersen, Karin Hedebo

    1998-01-01

    observed, but can not represent the mature deposits satisfactorily. The chemical composition of the mature deposits indicate, that sulphate based consolidation is of importance in the deposit maturation.The chemical elements of primary interest in coal-straw co-combustion are K and Cl, which are both...... introduced with the straw was bonded as K-Al-silicate during combustion, and the remaining available K formed K2SO4, which could participate in deposit formation and consolidation. No significant participation of K was seen in the coal ash deposits, whereas K was a large contributor the up- and downstream.......In conclusion, this study has provided new knowledge on the effects of coal-straw co-combustion on fouling deposit formation in a full-scale PF-boiler, including an experimental and thermodynamic evaluation of the behaviour of elements originating from the straw in deposits and fly ash, and the limits...

  7. Study on the NOx release rule along the boiler during pulverized coal combustion

    Institute of Scientific and Technical Information of China (English)

    JIN Jing; ZHANG Zhongxiao; LI Ruiyang

    2007-01-01

    Numerical simulation and experimental study on NOx release along the boiler during pulverized coal combustion have been conducted.With the increase of temperature the NOx emission increased and the peak value of NOx release moved forward.But when the temperature increased to a certain degree,NOx emission began to reduce.NOx emission increased with the increase of nitrogen content of coal.The peak value of NOx release moved backwards with the increase of coal rank.NOx emission increased obviously with the increase of stoichiometric ratio.There existed a critical average diameter of the pulverized coal (de).If d≤dc,NOx emission reduced with the decrease of pulverized coal size.If d>de,NOx emission reduced with the increase of the pulverized coal size.The results showed that the simulation results are in agreement with the experimental results for concentration distribution of NOx along the axis of the furnace.

  8. New technologies reducing emissions from combustion of biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Oravainen, H.

    1997-12-31

    In reducing CO{sub 2} emissions, bioenergy will be the most important source of renewable energy in the next few decades. In principle, combustion of biomass is friendly to the environment because CO{sub 2} released during combustion is recycled back into natural circulation. Biofuels normally contain little nitrogen and sulphur. However, depending on the combustion technology used, emissions may be quite high. This is true of combustion of biomass fuels in small appliances like wood stoves, fireplaces, small boilers etc. When fuels having high content of volatile matter are burnt in appliances using batch type combustion, the process is rather an unsteady-state combustion. Emissions of carbon monoxide, other combustible gases and particulates are quite difficult to avoid. With continuous combustion processes this is not normally a problem. This conference paper presents some means of reducing emissions from combustion of biofuels. 5 refs., 4 figs.

  9. Clean coal technology: Export finance programs

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-30

    Participation by US firms in the development of Clean Coal. Technology (CCT) projects in foreign countries will help the United States achieve multiple national objectives simultaneously--addressing critical goals related to energy, environmental technology, industrial competitiveness and international trade. US participation in these projects will result in an improved global environment, an improvement in the balance of payments and an increase in US jobs. Meanwhile, host countries will benefit from the development of economically- and environmentally-sound power facilities. The Clean Air Act Amendments of 1990 (Public Law 101-549, Section 409) as supplemented by a requirement in the Energy Policy Act of 1992 (Public Law 102-486, Section 1331(f)) requires that the Secretary of Energy, acting through the Trade Promotion Coordinating Committee Subgroup on Clean Coal Technologies, submit a report to Congress with information on the status of recommendations made in the US Department of Energy, Clean Coal Technology Export Programs, Report to the United States Congress, February 1992. Specific emphasis is placed on the adequacy of financial assistance for export of CCTS. This report fulfills the requirements of the Act. In addition, although this report focuses on CCT power projects, the issues it raises about the financing of these projects are also relevant to other CCT projects such as industrial applications or coal preparation, as well as to a much broader range of energy and environmental technology projects worldwide.

  10. Mercury speciation and fine particle size distribution on combustion of Chinese coals

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lei; Wang, Shuxiao; Hao, Jiming [Tsinghua Univ., Beijing (China). Dept. of Environmental Science and Engineering and State Key Joint Lab. of Environment Simulation and Pollution Control; Daukoru, Michael; Torkamani, Sarah; Biswas, Pratim [Washington Univ., St. Louis, MO (United States). Aerosol and Air Quality Research Lab.

    2013-07-01

    Coal combustion is the dominant anthropogenic mercury emission source of the world. Electrostatic precipitator (ESP) can remove almost all the particulate mercury (Hg{sub p}), and wet flue gas desulfurization (WFGD) can retain a large part of the gaseous oxidized mercury (Hg{sup 2+}). Only a small percentage of gaseous elemental mercury (Hg{sup 0}) can be abated by the air pollution control devices (APCDs). Therefore, the mercury behavior across APCDs largely depends on the mercury speciation in the flue gas exhausting from the coal combustor. To better understand the formation process of three mercury species, i.e. Hg{sup 0}, Hg{sup 2+} and Hg{sub p}, in gaseous phase and fine particles, bench-scale measurements for the flue gas exhausting from combustion of different types of coal in a drop-tube furnace set-up, were carried out. It was observed that with the limitation of reaction kinetics, higher mercury concentration in flue gas will lead to lower Hg{sup 2+} proportion. The concentration of chlorine has the opposite effect, not as significantly as that of mercury though. With the chlorine concentration increasing, the proportion of Hg{sup 2+} increases. Combusting the finer coal powder results in the formation of more Hg{sup 2+}. Mineral composition of coal and coal particle size has a great impact on fine particle formation. Al in coal is in favor of finer particle formation, while Fe in coal can benefit the formation of larger particles. The coexistence of Al and Si can strengthen the particle coagulation process. This process can also be improved by the feeding of more or finer coal powder. The oxy-coal condition can make for both the mercury oxidation process and the metal oxidation in the fine particle formation process.

  11. Effects of fractal surface on rheological behavior and combustion kinetics of modified brown coal water slurries

    Institute of Scientific and Technical Information of China (English)

    Zhifang Gao; Shuquan Zhu; Mingdong Zheng; Zhaojin Wu; Huihong Lu; Weiming Liu

    2015-01-01

    The paper reports the effects of surface fractal structures on the rheological behavior and combustion kinetics of raw brown coal and three modified coal water slurries (CWSs). The results show that the fractal structures and physicochemical properties of samples are dependent on various modification processes. The apparent viscosities of the coal water slurries increase with increasing surface fractal dimensions (D), especially with decreasing shear rates. Fur-thermore, it has been proved that the ignition temperatures and apparent activation energies of modified CWSs are lower than that of raw coal water slurry. Compared with the traditional qualitative analysis of the effect of pore structures on CWSs properties, D can more efficiently indicate the quantificational effect of pore structures on the rheological behavior and combustion kinetics of CWSs.

  12. Sulfur retention by ash during coal combustion. Part II. A model of the process

    Energy Technology Data Exchange (ETDEWEB)

    Vasilije Manovic; Borislav Grubor; Mladen Ilic; Branimir Jovancicevic

    2003-07-01

    An overall model for sulfur self-retention in ash during coal particle combustion is developed in this paper. It is assumed that sulfur retention during char combustion occurs due to the reaction between SO{sub 2} and CaO in the form of uniformly distributed non-porous grains. Parametric analysis shows that the process of sulfur self-retention is limited by solid diffusion through the non-porous product layer formed on the CaO grains and that the most important coal characteristics which influence sulfur self-retention are coal rank, content of sulfur forms, molar Ca/S ratio and particle radius. A comparison with the experimentally obtained values in a FB reactor showed that the model can adequately predict the kinetics of the process, the levels of the obtained values of the SSR efficiencies, as well as the influence of temperature and coal particle size.

  13. Sulfur retention by ash during coal combustion. Part II. A model of the process

    Directory of Open Access Journals (Sweden)

    BRANIMIR JOVANCICEVIC

    2003-03-01

    Full Text Available An overall model for sulfur self-retention in ash during coal particle combustion is developed in this paper. It is assumed that sulfur retention during char combustion occurs due to the reaction between SO2 and CaO in the form of uniformly distributed non-porous grains. Parametric analysis shows that the process of sulfur self-retention is limited by solid difussion through the non-porous product layer formed on the CaO grains and that the most important coal characteristics which influence sulfur self-retention are coal rank, content of sulfur forms, molar Ca/S ratio and particle radius. A comparison with the experimentally obtained values in a FB reactor showed that the model can adequately predict the kinetics of the process, the levels of the obtained values of the SSR efficiencies, as well as the influence of temperature and coal particle size.

  14. Investigation of the spraying mechanism and combustion of the suspended coal fuel

    Directory of Open Access Journals (Sweden)

    Murko Vasiliy I.

    2015-01-01

    Full Text Available This paper continues the earlier one [1]. It presents the results of the suspended coal fuel spraying with pneumo-mechanical sprayers followed by the fuel combustion in a vortex furnace. It is shown that, during the spraying, two qualitatively different systems of drops are forming. The first one with the “drops” diameter above 80 - 100 mm is presented by coal particles, the other - by water-coal drops. Different dynamics of temperature variation of the coal particle and WCF drops during their combustion is founded. The residence time of the burning particles and WCF drops in the vortex furnace is proportional to their diameter, which permits to provide their effective burn-off.

  15. Emission factors of gaseous carbonaceous species from residential combustion of coal and crop residue briquettes

    Institute of Scientific and Technical Information of China (English)

    Qin WANG; Chunmei GENG; Sihua LU; Wentai CHEN; Min SHAO

    2013-01-01

    Experiments were performed to measure the emission factors (EFs) of gaseous carbonaceous species, such as CO2, CO, CH4, and non-methane volatile organic compounds (NMVOCs), from the combustion of five types of coal of varying organic maturity and two types of biomass briquettes under residential burning conditions. Samples were collected in stainless steel canisters and 2,4- dinitrophenylhydrazine (DNPH) cartridges and were analyzed by GC FID/MS and HPLC, respectively. The EFs from crop residue briquette burning were generally higher than those from coals, with the exception of CO2. The dominant NMVOC species identified in coal smoke were carbonyls (41.7%), followed by C2 unsaturated hydrocarbons (29.1%) and aromatics (12.1%), while C2 unsaturated hydrocarbons were the dominant species (68.9%) emitted from the combustion of crop residue briquettes, followed by aromatics (14.4%). A comparison of burning normal crop residues in stoves and the open field indicated that briquettes emitted a larger proportion of ethene and acetylene. Both combustion efficiency and coal organic maturity had a significant impact on NMVOC EFs from burning coal: NMVOC emissions increased with increasing coal organic maturity but decreased as the combustion efficiency improved. Emissions from the combustion of crop residue briquettes from stoves occurred mainly during the smoldering process, with low combustion efficiency. Therefore, an improved stove design to allow higher combustion efficiency would be beneficial for reducing emissions of carbonaceous air pollutants.

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

    Energy Technology Data Exchange (ETDEWEB)

    Ottesen, D K; Thorne, L R

    1982-04-01

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

  17. Development and testing of commercial-scale, coal-fired combustion systems, Phase 3. Technical progress report, October 1990--December 1990

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-31

    The US Department of Energy`s Pittsburgh Energy Technology Center (PETC) is actively pursuing the development and testing of coal-fired combustion systems for residential, commercial, and industrial market sectors. In response, MTCI initiated the development of a new combustor technology based on the principle of pulse combustion under the sponsorship of PETC (Contract No. AC22-83PC60419). The initial pulse combustor development program was conducted in three phases (MTCI, Development of a Pulsed Coal Combustor Fired with CWM, Phase III Final Report, DOE Contract No. AC22-83PC60419, November 1986). Phase I included a review of the prior art in the area of pulse combustion and the development of pulse combustor design concepts. It led to the conclusion that pulse combustors offer technical and base-of-operation advantages over conventional burners and also indicated favorable economics for replacement of oil- and gas-fired equipment.

  18. Experimental Investigation into the Combustion Characteristics on the Co-firing of Biomass with Coal as a Function of Particle Size and Blending Ratio

    Energy Technology Data Exchange (ETDEWEB)

    Lkhagvadorj, Sh; Kim, Sang In; Lim, Ho; Kim, Seung Mo; Jeon, Chung Hwan [Pusan National Univ., Busan (Korea, Republic of); Lee, Byoung Hwa [Doosan Heavy Industries and Construction, Ltd., Changwon (Korea, Republic of)

    2016-01-15

    Co-firing of biomass with coal is a promising combustion technology in a coal-fired power plant. However, it still requires verifications to apply co-firing in an actual boiler. In this study, data from the Thermogravimetric analyzer(TGA) and Drop tube furnace(DTF) were used to obtain the combustion characteristics of biomass when co-firing with coal. The combustion characteristics were verified using experimental results including reactivity from the TGA and Unburned carbon(UBC) data from the DTF. The experiment also analyzed with the variation of the biomass blending ratio and biomass particle size. It was determined that increasing the biomass blending ratio resulted in incomplete chemical reactions due to insufficient oxygen levels because of the rapid initial combustion characteristics of the biomass. Thus, the optimum blending condition of the biomass based on the results of this study was found to be 5 while oxygen enrichment reduced the increase of UBC that occurred during combustion of blended biomass and coal.

  19. Low-rank coal research

    Energy Technology Data Exchange (ETDEWEB)

    Weber, G. F.; Laudal, D. L.

    1989-01-01

    This work is a compilation of reports on ongoing research at the University of North Dakota. Topics include: Control Technology and Coal Preparation Research (SO{sub x}/NO{sub x} control, waste management), Advanced Research and Technology Development (turbine combustion phenomena, combustion inorganic transformation, coal/char reactivity, liquefaction reactivity of low-rank coals, gasification ash and slag characterization, fine particulate emissions), Combustion Research (fluidized bed combustion, beneficiation of low-rank coals, combustion characterization of low-rank coal fuels, diesel utilization of low-rank coals), Liquefaction Research (low-rank coal direct liquefaction), and Gasification Research (hydrogen production from low-rank coals, advanced wastewater treatment, mild gasification, color and residual COD removal from Synfuel wastewaters, Great Plains Gasification Plant, gasifier optimization).

  20. The chemical transformation of calcium in Shenhua coal during combustion in a muffle furnace

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Sida [North China Electric Power Univ., Beijing (China). School of Energy, Power and Mechanical Engineering; Ministry of Education, Beijing (China). Key Lab. of Condition Monitoring and Control for Power Plant Equipment; Zhuo, Yuqun; Chen, Changhe [Tsinghua Univ., Beijing (China). Dept. of Thermal Engineering; Ministry of Education, Beijing (China). Key Lab. for Thermal Science and Power Engineering; Shu, Xinqian [China Univ. of Mining and Technology, Beijing (China). School of Chemical and Environmental Engineering

    2013-07-01

    The chemical reaction characteristics of calcium in three samples of Shenhua coal, i.e. raw sample, hydrochloric acid washed sample and hydrochloric acid washed light fraction, during combustion in a muffle furnace have been investigated in this paper. Ca is bound by calcite and organic matter in Shenhua coal. X ray diffraction (XRD) phase analysis has been conducted to these samples' combustion products obtained by heating at different temperatures. It has been found that the organically-bound calcium could easily react with clays and transform into gehlenite and anorthite partially if combusted under 815 C, whilst the excluded minerals promoted the conversion of gehlenite to anorthite. Calcite in Shenhua coal decomposed into calcium oxide and partially transformed into calcium sulfate under 815 C, and formed gehlenite and anorthite under 1,050 C. Calcite and other HCl-dissolved minerals in Shenhua coal were responsible mainly for the characteristic that the clay minerals in Shenhua coal hardly became mullite during combustion.

  1. Study of flame combustion of off-design binary coal blends in steam boilers

    Science.gov (United States)

    Kapustyanskii, A. A.

    2017-07-01

    Changes in the structure of the fuel consumption by the thermal power stations of Ukraine caused by failure in supplying anthracite from the Donets Basin are analyzed and the major tasks of maintaining the functioning of the coal industry are formulated. The possibility of using, in the near future, the flame combustion of off-design solid fuels in the power boilers of the thermal power plants and combined heat and power plants is studied. The article presents results of expert tests of the TPP-210A and TP-15 boilers under flame combustion of mixtures of anthracites, lean coal, and the coal from the RSA in various combinations. When combusting, such mixtures have higher values of the combustibles yield and the ash fusibility temperature. The existence of the synergetic effect in the flame combustion of binary coal blends with different degrees of metamorphism is discussed. A number of top-priority measures have been worked out that allow for switching over the boilers designed to be fired with anthracite to using blends of coals of different ranks. Zoned thermal analysis of the TP-15 boiler furnace was performed for numerical investigation of the temperature distribution between the furnace chamber zones and exploration of the possibility of the liquid slag disposal and the temperature conditions for realization of this process. A positive result was achieved by combusting anthracite culm (AC), the coal from the RSA, and their mixtures with lean coal within the entire range of the working loads of the boilers in question. The problems of normalization of the liquid slag flow were also successfully solved without closing the slag notch. The results obtained by balance experiments suggest that the characteristics of the flame combustion of a binary blend, i.e., the temperature conditions in the furnace, the support flame values, and the degree of the fuel burnout, are similar to the characteristics of the flame of the coal with a higher reactive capacity, which

  2. Co-combustion of solid recovered fuels in coal-fired power plants.

    Science.gov (United States)

    Thiel, Stephanie; Thomé-Kozmiensky, Karl Joachim

    2012-04-01

    Currently, in ten coal-fired power plants in Germany solid recovered fuels from mixed municipal waste and production-specific commercial waste are co-combusted and experiments have been conducted at other locations. Overall, in 2010 approximately 800,000 tonnes of these solid recovered fuels were used. In the coming years up to 2014 a slight decline in the quantity of materials used in co-combustions is expected. The co-combustion activities are in part significantly influenced by increasing power supply from renewable sources of energy and their impact on the regime of coal-fired power plants usage. Moreover, price trends of CO₂ allowances, solid recovered fuels as well as imported coal also have significant influence. In addition to the usage of solid recovered fuels with biogenic content, the co-combustion of pure renewable biofuels has become more important in coal-fired power plants. The power plant operators make high demands on the quality of solid recovered fuels. As the operational experience shows, a set of problems may be posed by co-combustion. The key factors in process engineering are firing technique and corrosion. A significant ecological key factor is the emission of pollutants into the atmosphere. The results of this study derive from research made on the basis of an extensive literature search as well as a survey on power plant operators in Germany. The data from operators was updated in spring 2011.

  3. Thermal analysis and kinetics of coal during oxy-fuel combustion

    Science.gov (United States)

    Kosowska-Golachowska, Monika

    2017-08-01

    The pyrolysis and oxy-fuel combustion characteristics of Polish bituminous coal were studied using non-isothermal thermogravimetric analysis. Pyrolysis tests showed that the mass loss profiles were almost similar up to 870°C in both N2 and CO2 atmospheres, while further mass loss occurred in CO2 atmosphere at higher temperatures due to char-CO2 gasification. Replacement of N2 in the combustion environment by CO2 delayed the combustion of bituminous coal. At elevated oxygen levels, TG/DTG profiles shifted through lower temperature zone, ignition and burnout temperatures decreased and mass loss rate significantly increased and complete combustion was achieved at lower temperatures and shorter times. Kinetic analysis for the tested coal was performed using Kissinger-Akahira-Sunose (KAS) method. The activation energies of bituminous coal combustion at the similar oxygen content in oxy-fuel with that of air were higher than that in air atmosphere. The results indicated that, with O2 concentration increasing, the activation energies decreased.

  4. Carbon-Centered Free Radicals in Particulate Matter Emissions from Wood and Coal Combustion

    OpenAIRE

    2009-01-01

    Electron paramagnetic resonance (EPR) spectroscopy was used to measure the free radicals in the particulate matter (PM) emissions from wood and coal combustion. The intensity of radicals in PM dropped linearly within two months of sample storage and stabilized after that. This factor of storage time was adjusted when comparing radical intensities among different PM samples. An inverse relationship between coal rank and free radical intensities in PM emissions was observed, which was in contra...

  5. 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.

  6. Fly ashes from coal and petroleum coke combustion: current and innovative potential applications.

    Science.gov (United States)

    González, Aixa; Navia, Rodrigo; Moreno, Natalia

    2009-12-01

    Coal fly ashes (CFA) are generated in large amounts worldwide. Current combustion technologies allow the burning of fuels with high sulfur content such as petroleum coke, generating non-CFA, such as petroleum coke fly ash (PCFA), mainly from fluidized bed combustion processes. The disposal of CFA and PCFA fly ashes can have severe impacts in the environment such as a potential groundwater contamination by the leaching of heavy metals and/or particulate matter emissions; making it necessary to treat or reuse them. At present CFA are utilized in several applications fields such as cement and concrete production, agriculture and soil stabilization. However, their reuse is restricted by the quality parameters of the end-product or requirements defined by the production process. Therefore, secondary material markets can use a limited amount of CFA, which implies the necessity of new markets for the unused CFA. Some potential future utilization options reviewed herein are zeolite synthesis and valuable metals extraction. In comparison to CFA, PCFA are characterized by a high Ca content, suggesting a possible use as neutralizers of acid wastewaters from mining operations, opening a new potential application area for PCFA that could solve contamination problems in emergent and mining countries such as Chile. However, this potential application may be limited by PCFA heavy metals leaching, mainly V and Ni, which are present in PCFA in high concentrations.

  7. Regional Effort to Deploy Clean Coal Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Gerald Hill; Kenneth Nemeth; Gary Garrett; Kimberly Sams

    2009-01-31

    The Southern States Energy Board's (SSEB) 'Regional Effort to Deploy Clean Coal Technologies' program began on June 1, 2003, and was completed on January 31, 2009. The project proved beneficial in providing state decision-makers with information that assisted them in removing barriers or implementing incentives to deploy clean coal technologies. This was accomplished through two specific tasks: (1) domestic energy security and diversity; and (2) the energy-water interface. Milestones accomplished during the project period are: (1) Presentations to Annual Meetings of SSEB Members, Associate Member Meetings, and the Gasification Technologies Council. (2) Energy: Water reports - (A) Regional Efforts to Deploy Clean Coal Technologies: Impacts and Implications for Water Supply and Quality. June 2004. (B) Energy-Water Interface Challenges: Coal Bed Methane and Mine Pool Water Characterization in the Southern States Region. 2004. (C) Freshwater Availability and Constraints on Thermoelectric Power Generation in the Southeast U.S. June 2008. (3) Blackwater Interactive Tabletop Exercise - Decatur, Georgia April 2007. (4) Blackwater Report: Blackwater: Energy and Water Interdependency Issues: Best Practices and Lessons Learned. August 2007. (5) Blackwater Report: BLACKWATER: Energy Water Interdependency Issues REPORT SUMMARY. April 2008.

  8. Results concerning a clean co-combustion technology of waste biomass with fossil fuel, in a pilot fluidised bed combustion facility

    Energy Technology Data Exchange (ETDEWEB)

    Ionel, Ioana; Trif-Tordai, Gavril; Ungureanu, Corneliu; Popescu, Francisc; Lontis, Nicolae [Politehnica Univ. Timisoara (Romania). Faculty for Mechanical Engineering

    2008-07-01

    The research focuses on a facility, the experimental results, interpretation and future plans concerning a new developed technology of using waste renewable energy by applying the cocombustion of waste biomass with coal, in a fluidised bed system. The experimental facility is working entirely in accordance to the allowed limits for the exhaust flue gas concentration, with special concern for typical pollutants. The experiments conclude that the technology is cleaner, has as main advantage the possibility to reduce both the SO{sub 2} and CO{sub 2} exhaust in comparison to standard fossil fuel combustion, under comparable circumstances. The combustion is occurring in a stable fluidised bed. (orig.)

  9. TECHNOLOGY DEMONSTRATION SUMMARY: THE AMERICAN COMBUSTION PYRETRON THERMAL DESTRUCTION SYSTEM AT THE U.S. EPA'S COMBUSTION FACILITY

    Science.gov (United States)

    The American Combustion Pyretron Thermal Destruction System at the U.S. EPA's Combustion Research Facility. Under the auspices of the Superfund Innovative Technology Evaluation, or SITE, program, a critical assessment was made of the American Combustion Pyretron™ oxygen enha...

  10. Modeling of pulverized coal combustion stabilization by means of plasma torches

    Energy Technology Data Exchange (ETDEWEB)

    Miroslav Sijercic; Srdjan Belosevic; Predrag Stefanovic [VINCA Institute of Nuclear Science, Belgrade (Serbia and Montenegro)

    2005-07-01

    Application of plasma-system for pulverized coal ignition and combustion stabilization in utility boiler furnaces promises to achieve certain savings compared to the use of heavy oil burners. Plasma torches are built in air-coal dust mixture ducts between coal mills and burners. Characteristics of processes in the ducts with plasma-system for pulverized coal combustion stabilization are analyzed in the paper, with respect to the modeling and numerical simulation of mass, momentum and heat transfer in two-phase turbulent gas particle flow. The simulations have been performed for three different geometries of the air-coal dust mixture ducts with plasma torches, for TENT A1 utility boiler and pulverized lignite Kolubara-Field 'D'. Selected results of numerical simulation of processes are presented. The plasma-system thermal effect is discussed regarding corresponding savings of liquid fuel. The results of numerical simulations have been analyzed with respect to the processes in the duct and especially with respect to the influence of the duct shape to a temperature field at the out let cross section, as a basis for the duct geometry optimization. It has been emphasized that numerical simulation of processes can be applied in analysis and optimization of pulverized coal ignition and combustion stabilization and enables efficient and cost-effective scaling-up procedure from laboratory to industrial level. 22 refs., 4 figs.

  11. Combustion and emissions characterization of pelletized coal fuels. Technical report, December 1, 1992--February 28, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Rajan, S. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mechanical Engineering and Energy Processes

    1993-05-01

    The aim of this project is to demonstrate that sorbent-containing coal pellets made from low grade coal or coal wastes are viable clean burning fuels, and to compare their performance with that of standard run-of-mine coal. Fuels to be investigated are: (a) carbonated pellets containing calcium hydroxide sorbent, (b) coal fines-limestone pellets with cornstarch as binder, (c) pellets made from preparation plant recovered coal containing limestone sorbent and gasification tar as binder, and (d) a standard run-of-mine Illinois seam coal. The fuels will be tested in a laboratory scale 411 diameter circulating fluidized bed combustor. Progress this quarter has centered on the development of a hydraulic press based pellet mill capable of the high compaction pressures necessary to produce the gasification tar containing pellets outlined in (c) above. Limited quantities of the pellets have been made, and the process is being fine tuned before proceeding into the production mode. Tests show that the moisture content of the coal is an important parameter that needs to be fixed within narrow limits for a given coal and binder combination to produce acceptable pellets. Combustion tests with these pellet fuels and the standard coal are scheduled for the next quarter.

  12. Geochemical database of feed coal and coal combustion products (CCPs) from five power plants in the United States

    Science.gov (United States)

    Affolter, Ronald H.; Groves, Steve; Betterton, William J.; William, Benzel; Conrad, Kelly L.; Swanson, Sharon M.; Ruppert, Leslie F.; Clough, James G.; Belkin, Harvey E.; Kolker, Allan; Hower, James C.

    2011-01-01

    The principal mission of the U.S. Geological Survey (USGS) Energy Resources Program (ERP) is to (1) understand the processes critical to the formation, accumulation, occurrence, and alteration of geologically based energy resources; (2) conduct scientifically robust assessments of those resources; and (3) study the impacts of energy resource occurrence and (or) their production and use on both the environment and human health. The ERP promotes and supports research resulting in original, geology-based, non-biased energy information products for policy and decision makers, land and resource managers, other Federal and State agencies, the domestic energy industry, foreign governments, non-governmental groups, and academia. Investigations include research on the geology of oil, gas, and coal, and the impacts associated with energy resource occurrence, production, quality, and utilization. The ERP's focus on coal is to support investigations into current issues pertaining to coal production, beneficiation and (or) conversion, and the environmental impact of the coal combustion process and coal combustion products (CCPs). To accomplish these studies, the USGS combines its activities with other organizations to address domestic and international issues that relate to the development and use of energy resources.

  13. Preparation and evaluation of coal-derived activated carbons for removal of mercury vapor from simulated coal combustion flue fases

    Science.gov (United States)

    Hsi, H.-C.; Chen, S.; Rostam-Abadi, M.; Rood, M.J.; Richardson, C.F.; Carey, T.R.; Chang, R.

    1998-01-01

    Coal-derived activated carbons (CDACs) were tested for their suitability in removing trace amounts of vapor-phase mercury from simulated flue gases generated by coal combustion. CDACs were prepared in bench-scale and pilot-scale fluidized-bed reactors with a three-step process, including coal preoxidation, carbonization, and then steam activation. CDACs from high-organicsulfur Illinois coals had a greater equilibrium Hg0 adsorption capacity than activated carbons prepared from a low-organic-sulfur Illinois coal. When a low-organic-sulfur CDAC was impregnated with elemental sulfur at 600 ??C, its equilibrium Hg0 adsorption capacity was comparable to the adsorption capacity of the activated carbon prepared from the high-organicsulfur coal. X-ray diffraction and sulfur K-edge X-ray absorption near-edge structure examinations showed that the sulfur in the CDACs was mainly in organic forms. These results suggested that a portion of the inherent organic sulfur in the starting coal, which remained in the CDACs, played an important role in adsorption of Hg0. Besides organic sulfur, the BET surface area and micropore area of the CDACs also influenced Hg0 adsorption capacity. The HgCl2 adsorption capacity was not as dependent on the surface area and concentration of sulfur in the CDACs as was adsorption of Hg0. The properties and mercury adsorption capacities of the CDACs were compared with those obtained for commercial Darco FGD carbon.

  14. Fractionation and speciation of arsenic in fresh and combusted coal wastes from Yangquan, northern China.

    Science.gov (United States)

    Gao, Xubo; Wang, Yanxin; Hu, Qinhong

    2012-02-01

    In this study, the content and speciation of arsenic in coal waste and gas condensates from coal waste fires were investigated, respectively, using the digestion and sequential extraction methods. The fresh and fired-coal waste samples were collected from Yangquan, which is one of the major coal production regions in northern China. High-performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) was used to determine the concentrations of four major arsenic species [As(III), As(V), monomethylarsonic acid (MMA) and dimethylarsenic acid (DMA)] in the extracts, while ICP-MS was used to measure total As content. Arsenic content in the investigated coal wastes and the condensate ranges between 23.3 and 69.3 mg/kg, which are higher than its reported average content in soils. Arsenic in coal waste exists primarily in the residual fraction; this is followed in decreasing order by the organic matter-bound, Fe-Mn oxides-bound, exchangeable, carbonates-bound, and water-soluble fractions. The high content of arsenic in the condensates indicates that combustion or spontaneous combustion is one of the major ways for arsenic release into the environment from coal waste. About 15% of the arsenic in the condensate sample is labile and can release into the environment under leaching processes. The water extractable arsenic (WEA) in the fresh coal waste, fired coal wastes, and the condensate varied between 14.6 and 341 μg/kg, with As(V) as the major species. Furthermore, both MMA and DMA were found in fresh coal wastes, fired coal wastes, and the condensate. © Springer Science+Business Media B.V. 2011

  15. Relevance of Clean Coal Technology for India’s Energy Security: A Policy Perspective

    Science.gov (United States)

    Garg, Amit; Tiwari, Vineet; Vishwanathan, Saritha

    2017-07-01

    Climate change mitigation regimes are expected to impose constraints on the future use of fossil fuels in order to reduce greenhouse gas (GHG) emissions. In 2015, 41% of total final energy consumption and 64% of power generation in India came from coal. Although almost a sixth of the total coal based thermal power generation is now super critical pulverized coal technology, the average CO2 emissions from the Indian power sector are 0.82 kg-CO2/kWh, mainly driven by coal. India has large domestic coal reserves which give it adequate energy security. There is a need to find options that allow the continued use of coal while considering the need for GHG mitigation. This paper explores options of linking GHG emission mitigation and energy security from 2000 to 2050 using the AIM/Enduse model under Business-as-Usual scenario. Our simulation analysis suggests that advanced clean coal technologies options could provide promising solutions for reducing CO2 emissions by improving energy efficiencies. This paper concludes that integrating climate change security and energy security for India is possible with a large scale deployment of advanced coal combustion technologies in Indian energy systems along with other measures.

  16. Emission, distribution and toxicity of polycyclic aromatic hydrocarbons (PAHs) during municipal solid waste (MSW) and coal co-combustion.

    Science.gov (United States)

    Peng, Nana; Li, Yi; Liu, Zhengang; Liu, Tingting; Gai, Chao

    2016-09-15

    Emission and distribution characteristics of polycyclic aromatic hydrocarbons (PAHs) were investigated during municipal solid waste (MSW) and coal combustion alone and MSW/coal blend (MSW weight fraction of 25%) co-combustion within a temperature range of 500°C-900°C. The results showed that for all combustion experiments, flue gas occupied the highest proportion of total PAHs and fly ash contained more high-ring PAHs. Moreover, the 3- and 4-ring PAHs accounted for the majority of total PAHs and Ant or Phe had the highest concentrations. Compared to coal, MSW combustion generated high levels of total PAHs with the range of 111.28μg/g-10,047.22μg/g and had high toxicity equivalent value (TEQ). MSW/coal co-combustion generated the smallest amounts of total PAHs and had the lowest TEQ than MSW and coal combustion alone. Significant synergistic interactions occurred between MSW and coal during co-combustion and the interactions suppressed the formation of PAHs, especially hazardous high-ring PAHs and decreased the TEQ. The present study indicated that the reduction of the yield and toxicity of PAHs can be achieved by co-combustion of MSW and coal.

  17. Overview of the energy research and development program of the Federal Republic of Germany with special attention to coal utilization technology

    Energy Technology Data Exchange (ETDEWEB)

    Holighaus, R.

    1980-01-01

    The objectives, the content and the finding of the Energy Research and Development Program are outlined with special attention to coal utilization technology. The largest part of the program is borne by the Federal Ministry for Research and Technology. The distribution of pending program shows clearly the priority for 'Coal and other fossil sources' which in fact means coal, the only large domestic energy source. The development activities are divided into following sections (in the order of financial priority): electricity generation from coal, gas generation from coal, liquefaction of coal, coal production and direct combustion. The different development strategies which are applied in the individual fields of coal utilization are discussed in detail. Several newly developed technologies are now, or in the near future, ready for commercial application. From the developments the Federal Government also expects to increase the attractivity of German industries as partners of joint ventures with countries having large coal deposits.

  18. Strength and corrosion behavior of SiC - based ceramics in hot coal combustion environments

    Energy Technology Data Exchange (ETDEWEB)

    Breder, K.; Parten, R.J. [Oak Ridge National Lab., TN (United States)

    1996-08-01

    As part of an effort to evaluate the use of advanced ceramics in a new generation of coal-fired power plants, four SiC-based ceramics have been exposed to corrosive coal slag in a laboratory furnace and two pilot scale combustors. Initial results indicate that the laboratory experiments are valuable additions to more expensive pilot plant experiments. The results show increased corrosive attack with increased temperature, and that only slight changes in temperature may significantly alter the degree of strength degradation due to corrosive attack. The present results are part of a larger experimental matrix evaluating the behavior of ceramics in the coal combustion environment.

  19. Coal-fired open cycle MHD combustion plasmas - Chemical equilibrium and transport properties workshop results

    Science.gov (United States)

    Sullivan, L. D.; Klepeis, J. E.; Coderre, W. J.; Fischer, W. H.

    1980-01-01

    For electrical power generation utilizing a high temperature alkali-seeded coal combustion plasma, the certainty of high electrical conductivity in the presence of coal ash and trace impurities is vitally important, especially for use in extrapolation of existing designs to higher power levels, as envisioned for commercial applications. The paper surveys the results of the workshop which provides an industry wide overview of the computational methods and analyses that are currently in use. Attention is given to uncertainty bands for plasma electrical conductivity. Also discussed are other issues such as coal, slag, seed, and conductivity. Finally, the paper gives suggested areas for further work.

  20. Evaluation of Mercury Emissions to the Atmosphere from Coal Combustion, China

    Energy Technology Data Exchange (ETDEWEB)

    Ming Quan Zhang [Lanzhou Univ., Lanzhou (China). College of Resources and Environmental Science; Yuan Cheng Zhu; Ru Wen Deng [Lanzhou Univ., Lanzhou (China). College of Chemistry and Chemical Engineering

    2002-11-01

    Mercury emissions from the coal smoke is the main source of anthropogenic discharge and mercury pollution in atmosphere. The calculated total amount of mercury emissions of China in 1995 is approximately 213.8 tonnes, which accounts for c. 5% of estimated total global discharge of 4000 tonnes in the same period. From 1978 to 1995, total coal consumption increased fourfold. Based on these data it is estimated that the mercury emissions will increase at a rate of 5% a year, and the predicted emissions will be 273 tonnes in China in 2000. Controlling and solving mercury emissions from coal combustion are among the most important environmental tasks facing China.

  1. Investigation of the combustion characteristics of Zonguldak bituminous coal using DTA and DTG

    Energy Technology Data Exchange (ETDEWEB)

    Haykiri-Acma, H.; Yaman, S.; Kucukbayrak, S.; Okutan, H. [Istanbul Technical University, Istanbul (Turkey). Dept. of Chemical Engineering

    2006-06-21

    Combustion characteristics of coking, semicoking, and noncoking Turkish bituminous coal samples from Zonguldak basin were investigated applying differential thermal analysis (DTA) and differential thermogravimetry (DTG) techniques. Results were compared with that of the coke from Zonguldak bituminous coal, a Turkish lignite sample from Soma, and a Siberian bituminous coal sample. The thermal data from both techniques showed some differences depending on the proximate analyses of the samples. Noncombustible components of the volatile matter led to important changes in thermal behavior. The data front both methods were, evaluated jointly, and some thermal properties were interpreted considering these methods in a complementary combination.

  2. Nitrogen Chemistry in Fluidized Bed Combustion of Coal

    DEFF Research Database (Denmark)

    Jensen, Anker Degn

    plant were used for model verification. The simulations of the NO emission during staged combustion and NH3 injection for NO reduction were in qualitative agreement with the experimental data. A parametric study of the influence of operating conditions on the conversion of fuel-N to NO showed...... are subjected to some uncertainty, and a sensitivity analysis of the predicted NO emission was carried out. The analysis showed that the predicted NO emission is sensitive to both hydrodynamic and combustion-related parameters. The most important hydrodynamic parameters were the minimum fluidization velocity......, the gas interchange coefficient, the bubble size and the bubble rise velocity. The most important combustion parameters were the rate of CO and CH4 combustion and the fraction of CO produced from char combustion. By using a rate of production analysis, the important reactions in the NO model were...

  3. Catalytic coal gasification: an emerging technology.

    Science.gov (United States)

    Hirsch, R L; Gallagher, J E; Lessard, R R; Wesslhoft, R D

    1982-01-08

    Catalytic coal gasification is being developed as a more efficient and less costly approach to producing methane from coal. With a potassium catalyst all the reactions can take place at one temperature, so that endothermic and exothermic reactions can be integrated in a single reactor. A key aspect of the concept involves continuous recycling of product carbon monoxide and hydrogen to the gasifier following separation of methane. Development of the process has advanced steadily since the basic concept was proposed in 1971. A 23-day demonstration run was recently completed in a process development unit with a coal feed rate of 1 ton per day. The next major step in the program will be to design and construct a large pilot plant to bring the technology to commercial readiness in the late 1980's.

  4. Coal Combustion Science quarterly progress report, January--March 1993. Task 1, Coal char combustion: Task 2,, Fate of mineral matter

    Energy Technology Data Exchange (ETDEWEB)

    Hardesty, D.R. [ed.; Hurt, R.H.; Baxter, L.L.

    1994-02-01

    The objective of this work is to obtain insights into the mechanisms of combustion, fragmentation, and final burnout, and to use the insights to aid in the interpretation of the quantitative data generated in Subtasks 1 and 2. The initial image sequences for Illinois No. 6 coal confirm the presence of an early near-extinction process (discussed in previous reports) and the asymptotic nature of the carbon burnout process. The technique also provided important new insights into the processes of particle fragmentation and reagglomeration at high burnout. During this quarter, chemical fractionation tests on coals pulverized to different sizes were completed. These data will help us to asses the accuracy of the fuels characterizations for the purpose of interpreting inorganic release during coal devolatilization. Chemical fractionation tests on mineral species are proceeding for the same purposes, but these are not yet completed.

  5. Emission factors of polycyclic aromatic hydrocarbons from domestic coal combustion in China.

    Science.gov (United States)

    Geng, Chunmei; Chen, Jianhua; Yang, Xiaoyang; Ren, Lihong; Yin, Baohui; Liu, Xiaoyu; Bai, Zhipeng

    2014-01-01

    Domestic coal stove is widely used in China, especially for countryside during heating period of winter, and polycyclic aromatic hydrocarbons (PAHs) are important in flue gas of the stove. By using dilution tunnel system, samples of both gaseous and particulate phases from domestic coal combustion were collected and 18 PAH species were analyzed by GC-MS. The average emission factors of total 18 PAH species was 171.73 mg/kg, ranging from 140.75 to 229.11 mg/kg for bituminous coals, while was 93.98 mg/kg, ranging from 58.48 to 129.47 mg/kg for anthracite coals. PAHs in gaseous phases occupied 95% of the total of PAHs emission of coal combustion. In particulate phase, 3-ring and 4-ring PAHs were the main components, accounting for 80% of the total particulate PAHs. The total toxicity potency evaluated by benzo[a]pyrene-equivalent carcinogenic power, sum of 7 carcinogenic PAH components and 2,3,7,8-tetrachlorodibenzodioxin had a similar tendency. And as a result, the toxic potential of bituminous coal was higher than that of anthracite coal. Efficient emission control should be conducted to reduce PAH emissions in order to protect ecosystem and human health.

  6. Soot, organics, and ultrafine ash from air- and oxy-fired coal combustion

    KAUST Repository

    Andersen, Myrrha E.

    2016-10-19

    Pulverized bituminous coal was burned in a 10. W externally heated entrained flow furnace under air-combustion and three oxy-combustion inlet oxygen conditions (28, 32, and 36%). Experiments were designed to produce flames with practically relevant stoichiometric ratios (SR. =1.2-1.4) and constant residence times (2.3. s). Size-classified fly ash samples were collected, and measurements focused on the soot, elemental carbon (EC), and organic carbon (OC) composition of the total and ultrafine (<0.6. μm) fly ash. Results indicate that although the total fly ash carbon, as measured by loss on ignition, was always acceptably low (<2%) with all three oxy-combustion conditions lower than air-combustion, the ultrafine fly ash for both air-fired and oxy-fired combustion conditions consists primarily of carbonaceous material (50-95%). Carbonaceous components on particles <0.6. μm measured by a thermal optical method showed that large fractions (52-93%) consisted of OC rather than EC, as expected. This observation was supported by thermogravimetric analysis indicating that for the air, 28% oxy, and 32% oxy conditions, 14-71% of this material may be OC volatilizing between 100. C and 550. C with the remaining 29-86% being EC/soot. However, for the 36% oxy condition, OC may comprise over 90% of the ultrafine carbon with a much smaller EC/soot contribution. These data were interpreted by considering the effects of oxy-combustion on flame attachment, ignition delay, and soot oxidation of a bituminous coal, and the effects of these processes on OC and EC emissions. Flame aerodynamics and inlet oxidant composition may influence emissions of organic hazardous air pollutants (HAPs) from a bituminous coal. During oxy-coal combustion, judicious control of inlet oxygen concentration and placement may be used to minimize organic HAP and soot emissions.

  7. Application of rubber anti-aging agents in preventing coal spontaneous combustion

    Energy Technology Data Exchange (ETDEWEB)

    Yu, S.; Zhang, R.; Yang, Y.; Yang, H.; Fan, X.

    1999-07-01

    Based on the mechanism of rubber aging and action of anti-aging agents in preventing rubber aging, the free radical chain reaction mechanism of the oxidation of coal was discussed and compound stopping agents were introduced in the paper. The rubber anti-aging agents of aromatic amine are selected for the stopping agent of preventing coal spontaneous combustion. The stopping action of these anti-aging agents and common inorganic salt stopping agents for long flame coal in Gengcun Colliery, Yima city, Henan province in China is researched. The anti-aging agents for the long flame coal have the prominent efficiency and fine stopping action in later period, and inorganic stopping agents containing magnesium chloride salt for the long flame coal have the prominent efficiency in early period, but the compound stopping agents that are composed of the rubber anti-aging agents and magnesium chloride have longer life.

  8. Status and issue of coal mine safety technology development in Japan and international co-operation

    Energy Technology Data Exchange (ETDEWEB)

    Nakmura, K. [Ministry of International Trade and Industry, Tokyo (Japan). Mine Safety Division, Environmental Protection and Industrial Location Bureau

    2001-03-01

    Recent trends in coal mine accidents in Japan are reviewed and the incident of mine fire at the Ikeshima coal mine in Nagasaki Prefecture in February 2000 reported. An overview is given of safety projects underway in Japan or jointly with Australia. Cooperative projects to prevent spontaneous combustion to develop underground monitoring techniques, and to transfer safety technologies from Japan abroad are outlined. Other projects carried out by the Japan International Cooperation Agency (JICA) are listed. Japan's long-term policy for safety technology development is outlined. 4 figs., 6 tabs.

  9. Geochemistry of Permian Coal and Its Combustion Residues in Huainan Coalfield, China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    INAA (instrumental neutron activation analysis) was used to determine the contents of trace elements in coal samples from 11 workable Permian coal seams in Huainan coalfield. With XRFS (X-ray fluorescence spectrometry), the geochemical composition of its combustion residues from Tianjiaan Power Plant and Luohe Power Plant was analyzed. In addition, the electron microprobe was employed to study the chemical composition of some fly ashes and bottom ashes. Compared with those of the coals around the world, most trace elements of the Huainan coal are characterized by a normal abundance.Like most coals worldwide, the elements Se, S, As, Sb, Br, U and Cl are enriched in Huainan coal according to Clarks value, while the other elements tend to be diluted. The large fluctuation in the contents of trace elements in this kind of coal demonstrates great differences in coal seams. On the other hand, the contents of these elements are very similar in different bottom and fly ash samples. The elements with low organic affinity tend to concentrate in fly and bottom ash than in coal, especially those elements associated with Fe. However, the elements with strong organic affinity tend to be volatile during the combustion. Moreover, the abundance of the elements in fly ash and bottom ash changes with different densities and with different particle sizes. The bottom and fly ashes consist of glass, lime,mullite, coal residues and ferrite minerals. Some residual chars contain higher contents of volatile elements, such as S, P, Cl and As, indicating that the ash containing more residual chars has a strong adsorption of some hazardous elements, suggesting a possible utilization of power plant ash in the field of water cleaning.

  10. Studying flame combustion of coal-water slurries in the furnaces of power-generating boilers

    Science.gov (United States)

    Osintsev, K. V.

    2012-06-01

    Matters concerned with organizing combustion of different types of coal-water slurries in coalfired boilers at thermal power stations are considered. Recommendations for improving the economic and environmental indicators and for achieving more reliable operation of furnace devices and boiler as a whole are given.

  11. Analysis of Index Gases of Coal Spontaneous Combustion Using Fourier Transform Infrared Spectrometer

    Directory of Open Access Journals (Sweden)

    Xiaojun Tang

    2014-01-01

    Full Text Available Analysis of the index gases of coal for the prevention of spontaneous combustion is of great importance for the enhancement of coal mine safety. In this work, Fourier Transform Infrared Spectrometer (FTIRS is presented to be used to analyze the index gases of coal in real time to monitor spontaneous combustion conditions. Both the instrument parameters and the analysis method are introduced at first by combining characteristics of the absorption spectra of the target analyte with the analysis requirements. Next, more than ten sets of the gas mixture containing ten components (CH4, C2H6, C3H8, iso-C4H10, n-C4H10, C2H4, C3H6, C2H2, CO, and CO2 are included and analyzed with a Spectrum Two FTIRS made by Perkin Elmer. The testing results show that the detection limit of most analytes is less than 2×10-6. All the detection limits meet the monitoring requirements of coal spontaneous combustion in China, which means that FTIRS may be an ideal instrument and the analysis method used in this paper is sufficient for spontaneous combustion gas monitoring on-line and even in situ, since FTIRS has many advantages such as fast analysis, being maintenance-free, and good safety.

  12. Modeling the temperature in coal char particle during fluidized bed combustion

    Energy Technology Data Exchange (ETDEWEB)

    Vasilije Manovic; Mirko Komatina; Simeon Oka [University of Belgrade, Belgrade (Serbia)

    2008-05-15

    The temperatures of a coal char particle in hot bubbling fluidized bed (FB) were analyzed by a model of combustion. The unsteady model includes phenomena of heat and mass transfer through a porous char particle, as well as heterogeneous reaction at the interior char surface and homogeneous reaction in the pores. The parametric analysis of the model has shown that above 550{sup o}C combustion occurs under the regime limited by diffusion. The experimental results of temperature measurements by thermocouple in the particle center during FB combustion at temperatures in the range 590-710{sup o}C were compared with the model predictions. Two coals of different rank were used: lignite and brown coal, with particle size in the range 5-10 mm. The comparisons have shown that the model can adequately predict the histories of temperatures in char particles during combustion in FB. In the first order, the model predicts the influence of the particle size, coal rank (via porosity), and oxygen concentration in its surroundings. 53 refs., 6 figs., 2 tabs.

  13. Oxy-fuel combustion of millimeter-sized coal char: Particle temperatures and NO formation

    DEFF Research Database (Denmark)

    Brix, Jacob; Navascués, Leyre Gómez; Nielsen, Joachim Bachmann;

    2013-01-01

    In this work, differences in particle temperature and NO yield during char oxidation in O2/N2 and O2/CO2 atmospheres, respectively, have been examined. A laboratory scale fixed bed reactor, operated isothermally at 1073 K, was used for combustion of millimeter-sized lignite and bituminous coal ch...

  14. Effects of coal combustion and gasification upon lung structure and function. Quarterly progress report

    Energy Technology Data Exchange (ETDEWEB)

    Hinton, Dr., David E.

    1980-12-12

    The effects on lungs of emissions from fluidized-bed combustion and coal gasification on man are being studied by inhalation experiments and intratracheal administration of fly ash to hamsters. The hamsters are sacrificed at 1, 3, 6, 9 and 30 days and the lungs examined by methods which are described. (LTN)

  15. Sulfur emission from Victorian brown coal under pyrolysis, oxy-fuel combustion and gasification conditions.

    Science.gov (United States)

    Chen, Luguang; Bhattacharya, Sankar

    2013-02-05

    Sulfur emission from a Victorian brown coal was quantitatively determined through controlled experiments in a continuously fed drop-tube furnace under three different atmospheres: pyrolysis, oxy-fuel combustion, and carbon dioxide gasification conditions. The species measured were H(2)S, SO(2), COS, CS(2), and more importantly SO(3). The temperature (873-1273 K) and gas environment effects on the sulfur species emission were investigated. The effect of residence time on the emission of those species was also assessed under oxy-fuel condition. The emission of the sulfur species depended on the reaction environment. H(2)S, SO(2), and CS(2) are the major species during pyrolysis, oxy-fuel, and gasification. Up to 10% of coal sulfur was found to be converted to SO(3) under oxy-fuel combustion, whereas SO(3) was undetectable during pyrolysis and gasification. The trend of the experimental results was qualitatively matched by thermodynamic predictions. The residence time had little effect on the release of those species. The release of sulfur oxides, in particular both SO(2) and SO(3), is considerably high during oxy-fuel combustion even though the sulfur content in Morwell coal is only 0.80%. Therefore, for Morwell coal utilization during oxy-fuel combustion, additional sulfur removal, or polishing systems will be required in order to avoid corrosion in the boiler and in the CO(2) separation units of the CO(2) capture systems.

  16. Study of boron behaviour in two Spanish coal combustion power plants.

    Science.gov (United States)

    Ochoa-González, Raquel; Cuesta, Aida Fuente; Córdoba, Patricia; Díaz-Somoano, Mercedes; Font, Oriol; López-Antón, M Antonia; Querol, Xavier; Martínez-Tarazona, M Rosa; Giménez, Antonio

    2011-10-01

    A full-scale field study was carried out at two Spanish coal-fired power plants equipped with electrostatic precipitator (ESP) and wet flue gas desulfurisation (FGD) systems to investigate the distribution of boron in coals, solid by-products, wastewater streams and flue gases. The results were obtained from the simultaneous sampling of solid, liquid and gaseous streams and their subsequent analysis in two different laboratories for purposes of comparison. Although the final aim of this study was to evaluate the partitioning of boron in a (co-)combustion power plant, special attention was paid to the analytical procedure for boron determination. A sample preparation procedure was optimised for coal and combustion by-products to overcome some specific shortcomings of the currently used acid digestion methods. In addition boron mass balances and removal efficiencies in ESP and FGD devices were calculated. Mass balance closures between 83 and 149% were obtained. During coal combustion, 95% of the incoming boron was collected in the fly ashes. The use of petroleum coke as co-combustible produced a decrease in the removal efficiency of the ESP (87%). Nevertheless, more than 90% of the remaining gaseous boron was eliminated via the FGD in the wastewater discharged from the scrubber, thereby causing environmental problems.

  17. Lung X-ray changes in skeletal fluorosis caused by coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Liu, B.K. [Hubei Sanitary-Epidemiological Station, Wuhan (China)

    1996-02-01

    Lung X-ray findings are reported in 45 cases with skeletal fluorosis in an area contaminated by coal combustion. The findings include chronic bronchitis, with diffuse interstitial fibrosis and pulmonary emphysema. The degree of pulmonary pathological findings and skeletal fluorosis is correlated with patient age. Among the 45 cases were 5 with cardio-pulmonary disease and 5 with tuberculosis.

  18. Behavior of fluorine in the combustion of Chinese coal in small furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Dan Liu; Yuji Sakai; Mitsuo Yamamoto; Masayoshi Sadakata [Ariake National College of Technology, Fukuoka (Japan). Department of Chemistry Science and Engineering

    2006-08-15

    Research into fluoride emissions from coal-combustion systems is becoming increasingly important as the issue of fluoride pollution in China becomes more serious. In some rural areas in China, indoor fluoride pollution has particularly been caused by the use of high fluorine content coal in stoves. As a result, many residents suffer from dental fluorosis and bone fluorosis. In this study, X-ray diffraction (XRD) analysis was carried out to confirm the mode by which inorganic fluorides exist in such coals. Analytical results showed that inorganic fluorides in Chinese coals exist mainly as muscovite and apatite. The fluorine concentration in gases emitted from a boat in a quartz tube furnace was measured during combustion of volatile matter and char. The times for volatile matter and char combustions were determined through continuous monitoring of SO{sub 2}. Experimental results under different combustion conditions showed that fluoride in the emitted gas increased with an increase in oxygen concentration and temperature, while fluoride in the residue decreased with the increase in oxygen concentration and temperature. 23 refs., 8 figs., 2 tabs.

  19. Rheology of fly ashes from coal and biomass co-combustion

    DEFF Research Database (Denmark)

    Arvelakis, Stelios; Frandsen, Flemming

    2010-01-01

    The presence of large amounts of alkali metals, chlorine and sulphur in most biomass fuels - compared to coal - can create serious ash-related problems such as deposition, agglomeration and/or corrosion. This paper discusses the viscosity characteristics of fly ash from the co-combustion of various...

  20. Implementation of Paste Backfill Mining Technology in Chinese Coal Mines

    OpenAIRE

    Qingliang Chang; Jianhang Chen; Huaqiang Zhou; Jianbiao Bai

    2014-01-01

    Implementation of clean mining technology at coal mines is crucial to protect the environment and maintain balance among energy resources, consumption, and ecology. After reviewing present coal clean mining technology, we introduce the technology principles and technological process of paste backfill mining in coal mines and discuss the components and features of backfill materials, the constitution of the backfill system, and the backfill process. Specific implementation of this technology a...

  1. Current and advanced NO/sub x/-control technology for coal-fired industrial boilers

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-01

    A NOx-control-technology assessment study of coal-fired industrial boilers was conducted to examine the effectiveness of combustion-modification methods, including low excess air, staged combustion, and burner modifications. Boiler types considered included overfed and underfed stokers, spreader stokers, pulverized-coal and coal-fired cyclone units. Significant variations in NOx emissions occur with boiler type, firing method, and coal type; a relative comparison of emission-control performance, cost, and operational considerations is presented for each method. Baseline (as-found) emissions from grate-fired stokers were shown to be in the range of 200 to 300 ppM. Similarly, as-found emissions from suspension-fired units were quite low (350 to 600 ppM) as compared to comparably designed utility-sized units. Low excess air was shown to be the most effective method on existing units, reducing emissions by approximately 10%. Evaluation of staged combustion and burner modification, however, were limited due to current boiler designs. Major hardware modification/design and implementation are necessary before the potential of these techniques can be fully evaluated. The study emphasized the numerous operational factors that are of major importance to the user in selecting and implementing a combustion-modification program, including energy considerations, incremental capital and operating costs, corrosion, secondary pollutants, and retrofit potential.

  2. Non-linear models: coal combustion efficiency and emissions control

    Energy Technology Data Exchange (ETDEWEB)

    Bulsari, A.; Wemberg, A.; Anttila, A.; Multas, A. [Nonlinear Solutions Oy, Turku (Finland)

    2009-04-15

    Today's power plants feel the pressure to limit their NOx emissions and improve their production economics. The article describes how nonlinear models are effective for process guidance of various kinds of processes, including coal fired boilers. These models were developed for the Naantati 2 boiler at the electricity and heat generating coal-fired plant in Naantali, near Turku, Finland. 4 refs., 6 figs.

  3. 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

    On February 14, 2002, President Bush announced the Clear Skies Initiative, a legislative proposal to control the emissions of nitrogen oxides (NO{sub x}), sulfur dioxide (SO{sub 2}), and mercury from power plants. In response to this initiative, the National Energy Technology Laboratory organized a Combustion Technology University Alliance and hosted a Solid Fuel Combustion Technology Alliance Workshop. The workshop identified multi-pollutant control; improved sorbents and catalysts; mercury monitoring and capture; and improved understanding of the underlying reaction chemistry occurring during combustion as the most pressing research needs related to controlling environmental emissions from fossil-fueled power plants. The Environmental Control Technology Laboratory will help meet these challenges and offer solutions for problems associated with emissions from fossil-fueled power plants. The goal of this project was to develop the capability and technology database needed to support municipal, regional, and national electric power generating facilities to improve the efficiency of operation and solve operational and environmental problems. In order to effectively provide the scientific data and the methodologies required to address these issues, the project included the following aspects: (1) Establishing an Environmental Control Technology Laboratory using a laboratory-scale, simulated fluidized-bed combustion (FBC) system; (2) Designing, constructing, and operating a bench-scale (0.6 MW{sub th}), circulating fluidized-bed combustion (CFBC) system as the main component of the Environmental Control Technology Laboratory; (3) Developing a combustion technology for co-firing municipal solid waste (MSW), agricultural waste, and refuse-derived fuel (RDF) with high sulfur coals; (4) Developing a control strategy for gaseous emissions, including NO{sub x}, SO{sub 2}, organic compounds, and heavy metals; and (5) Developing new mercury capturing sorbents and new

  4. The effect of fuel pyrolysis on the coal particle combustion: An analytical investigation

    Directory of Open Access Journals (Sweden)

    Baghsheikhi Mostafa

    2016-01-01

    Full Text Available The aim of this work is to analytically investigate the symmetrical combustion of an isolated coal particle with the fuel pyrolysis effect. The modelling concept of coal particles is similar to that of the liquid droplet combustion but in the case of coal devolatilization, the particles do not shrink like droplet does due to evaporation of liquid fuel. The rate of devolatilization of volatiles can be calculated using the equation that is similar to Arrhenius equation. This model is based on an assumption of combined quasi-steady and transient behaviour of the process and especially focuses on predicting the variations of temperature profile, radius of pyrolysis and transfer number. It is revealed that the entrance of pyrolysis effect into the governing equations leads to the reduction in the film radius and consequently a reduction in the stand-off ratio and transfer number.

  5. Upgraded Coal Interest Group

    Energy Technology Data Exchange (ETDEWEB)

    Evan Hughes

    2009-01-08

    The Upgraded Coal Interest Group (UCIG) is an EPRI 'users group' that focuses on clean, low-cost options for coal-based power generation. The UCIG covers topics that involve (1) pre-combustion processes, (2) co-firing systems and fuels, and (3) reburn using coal-derived or biomass-derived fuels. The UCIG mission is to preserve and expand the economic use of coal for energy. By reducing the fuel costs and environmental impacts of coal-fired power generation, existing units become more cost effective and thus new units utilizing advanced combustion technologies are more likely to be coal-fired.

  6. Implementation of Paste Backfill Mining Technology in Chinese Coal Mines

    Directory of Open Access Journals (Sweden)

    Qingliang Chang

    2014-01-01

    Full Text Available Implementation of clean mining technology at coal mines is crucial to protect the environment and maintain balance among energy resources, consumption, and ecology. After reviewing present coal clean mining technology, we introduce the technology principles and technological process of paste backfill mining in coal mines and discuss the components and features of backfill materials, the constitution of the backfill system, and the backfill process. Specific implementation of this technology and its application are analyzed for paste backfill mining in Daizhuang Coal Mine; a practical implementation shows that paste backfill mining can improve the safety and excavation rate of coal mining, which can effectively resolve surface subsidence problems caused by underground mining activities, by utilizing solid waste such as coal gangues as a resource. Therefore, paste backfill mining is an effective clean coal mining technology, which has widespread application.

  7. Implementation of paste backfill mining technology in Chinese coal mines.

    Science.gov (United States)

    Chang, Qingliang; Chen, Jianhang; Zhou, Huaqiang; Bai, Jianbiao

    2014-01-01

    Implementation of clean mining technology at coal mines is crucial to protect the environment and maintain balance among energy resources, consumption, and ecology. After reviewing present coal clean mining technology, we introduce the technology principles and technological process of paste backfill mining in coal mines and discuss the components and features of backfill materials, the constitution of the backfill system, and the backfill process. Specific implementation of this technology and its application are analyzed for paste backfill mining in Daizhuang Coal Mine; a practical implementation shows that paste backfill mining can improve the safety and excavation rate of coal mining, which can effectively resolve surface subsidence problems caused by underground mining activities, by utilizing solid waste such as coal gangues as a resource. Therefore, paste backfill mining is an effective clean coal mining technology, which has widespread application.

  8. Characterization, leachability and valorization through combustion of residual chars from gasification of coals with pine.

    Science.gov (United States)

    Galhetas, Margarida; Lopes, Helena; Freire, Márcia; Abelha, Pedro; Pinto, Filomena; Gulyurtlu, Ibrahim

    2012-04-01

    This paper presents the study of the combustion of char residues produced during co-gasification of coal with pine with the aim of characterizing them for their potential use for energy. These residues are generally rich in carbon with the presence of other elements, with particular concern for heavy metals and pollutant precursors, depending on the original fuel used. The evaluation of environmental toxicity of the char residues was performed through application of different leaching tests (EN12457-2, US EPA-1311 TCLP and EA NEN 7371:2004). The results showed that the residues present quite low toxicity for some of pollutants. However, depending on the fuel used, possible presence of other pollutants may bring environmental risks. The utilization of these char residues for energy was in this study evaluated, by burning them as a first step pre-treatment prior to landfilling. The thermo-gravimetric analysis and ash fusibility studies revealed an adequate thermochemical behavior, without presenting any major operational risks. Fluidized bed combustion was applied to char residues. Above 700°C, very high carbon conversion ratios were obtained and it seemed that the thermal oxidation of char residues was easier than that of the coals. It was found that the char tendency for releasing SO(2) during its oxidation was lower than for the parent coal, while for NO(X) emissions, the trend was observed to increase NO(X) formation. However, for both pollutants the same control techniques might be applied during char combustion, as for coal. Furthermore, the leachability of ashes resulting from the combustion of char residues appeared to be lower than those produced from direct coal combustion.

  9. Oxy-coal combustion in an entrained flow reactor: Application of specific char and volatile combustion and radiation models for oxy-firing conditions

    DEFF Research Database (Denmark)

    Álvarez, L.; Yin, Chungen; Riaza, J.

    2013-01-01

    implemented in CFD (Computational Fluid Dynamics) simulations of combustion of three coals under air-firing and various oxy-firing (21-35% vol O2 in O2/CO2 mixture) conditions in an EFR (entrained flow reactor). The predicted coal burnouts and gaseous emissions were compared against experimental results...

  10. Combustion of dense streams of coal particles. Final report, August 29, 1990--February 28, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Annamalai, K.; Gopalakrishnan, C.; Du, X.

    1994-05-01

    The USA consumes almost 94 quads of energy (1 quad = 10{sup 15} BTU or 1.05 {times} 10{sup 15} KJ). The utilities account for about 30 quads of fossil energy where coal is predominantly used as energy source. The coal is ground to finer size and fired into the boiler as dense suspension. Under dense conditions, the particles burn at slower rate due to deficient oxygen within the interparticle spacing. Thus interactions exist amongst the particles for dense clouds. While the earlier literature dealt with combustion processes of isolated particles, the recent research focusses upon the interactive combustion. The interactive combustion studies include arrays consisting of a finite number of particles, and streams and clouds of a large number of particles. Particularly stream combustion models assume cylindrical geometry and predict the ignition and combustion characteristics. The models show that the ignition starts homogeneously for dense streams of coal particles and the ignition time show a minimum as the stream denseness is increased, and during combustion, there appears to be an inner flame within the stream and an outer flame outside the stream for a short period of time. The present experimental investigation is an attempt to verify the model predictions. The set-up consists of a flat flame burner for producing hot vitiated gases, a locally fluidizing feeder system for feeding coal particles, a particle collection probe for collecting particles and an image processing system for analyzing the flame structure. The particles are introduced as a stream into the hot gases and subsequently they ignite and burn. The ash % of fired and collected particles are determined and used to estimate the gasification efficiency or burnt fraction. The parametric studies include gas temperature, oxygen % in gases, residence time, and A:F ratio of the stream.

  11. Study of the O2/CO2 combustion technology; Sanso nensho gijutsu ni kakawaru chosa kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Kato, M. [Center for Coal Utilization, Japan, Tokyo (Japan); Kiga, T.; Yamada, T. [Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan); Arai, K. [Nippon Sanso K.K., Tokyo (Japan); Mori, T. [Inst. of Research and Innovation, Tokyo (Japan); Kimura, N.; Okawa, M. [Electric Power Development Co. Ltd., Tokyo (Japan)

    1996-09-01

    This study is being progressed during a period from 1992 to 1999 as part of the NEDO`s clean coal technology program. This paper describes what has been discussed to date. The absorption method and the adsorption method may be used to recover CO2 as means to deal with the problem of global warming resulted from burning coals. These methods, however, have problems in economy caused from concentration of CO2 in flue gas being low. The present study is intended to raise the CO2 concentration in flue gas by using oxygen plus circulated flue gas in the place of combustion air, so that CO2 may be recovered as it is without being separated from the flue gas. Therefore, an oxygen-blown pulverized coal fired power generation plant having a cryogenic oxygen manufacturing equipment was designed to discuss the plant operability and economy, and the pulverized coal combustion technology by using a dynamic simulation. A large number of findings have been obtained already, and the study has reached a level at which grasping the whole image is now possible. 13 figs.

  12. Interactions of coal gangue and pine sawdust during combustion of their blends studied using differential thermogravimetric analysis.

    Science.gov (United States)

    Zhang, Yuanyuan; Zhang, Zhezi; Zhu, Mingming; Cheng, Fangqin; Zhang, Dongke

    2016-08-01

    The interactions between coal gangue and pine sawdust during the combustion process were studied using thermogravimetric analysis. The effect of the blending ratio, oxygen concentration and heating rate on the weight loss (TG) and differential thermogravimetric (TGA) profiles was examined. The TG and DTG curves of the blends were not additives of those of the individual materials, suggesting that interactions between coal gangue and pine sawdust had occurred during the combustion, especially in the temperature range of 400-600°C. Kinetic analysis confirmed that the combustion of coal gangue, pine sawdust and their blends was chemical reaction controlled. Further analysis revealed that the interactions between coal gangue and pine sawdust were primarily due to thermal effects rather than structural changes, with the thermal inertia of coal gangue dominating over the behaviour of the blends. The interactions decreased with decreasing the coal gangue ratio in the blend, oxygen concentration and heating rate.

  13. Experimental investigations on combustion and emission behaviour during oxy-coal combustion

    OpenAIRE

    Dhungel, Bhupesh

    2010-01-01

    As the most abundant non-renewable energy source available, coal has traditionally played a major role in ensuring the security of energy, and will continue to play a key role in the world energy mix. The burning of coal has however always been a subject of environmental concern. In recent years, the emission of green house gases and global climate change has emerged as the largest environmental challenge. As coal fired power plants are categorised among the least carbon efficient energy prod...

  14. NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    Jost O.L. Wendt

    2002-08-15

    This research project focuses on pollutants from the combustion of mixtures of dried municipal sewage sludge (MSS) and coal. The objective is to determine the relationship between (1) fraction sludge in the sludge/coal mixture, and (2) combustion conditions on (a) NOx concentrations in the exhaust, (b) the size segregated fine and ultra-fine particle composition in the exhaust, and (c) the partitioning of toxic metals between vapor and condenses phases, within the process. The proposed study will be conducted in concert with an existing ongoing research on toxic metal partitioning mechanisms for very well characterized pulverized coals alone. Both high NOx and low NOx combustion conditions will be investigated (unstaged and staged combustion). Tradeoffs between CO2 control, NOx control, and inorganic fine particle and toxic metal emissions will be determined. Previous research has yielded data on trace metal partitioning for MSS by itself, with natural gas assist, for coal plus MSS combustion together, and for coal alone. We have re-evaluated the inhalation health effects of ash aerosol from combustion of MSS both by itself and also together with coal. We have concluded that ash from the co-combustion of MSS and coal is very much worse from an inhalation health point of view, than ash from either MSS by itself or coal by itself. The reason is that ZnO is not the ''bad actor'' as had been suspected before, but the culprit is, rather, sulfated Zn. The MSS supplies the Zn and the coal supplies the sulfur, and so it is the combination of coal and MSS that makes that process environmentally bad. If MSS is to be burned, it should be burned without coal, in the absence of sulfur.

  15. Arsenic in coal of the Thar coalfield, Pakistan, and its behavior during combustion.

    Science.gov (United States)

    Ali, Jamshed; Kazi, Tasneem G; Baig, Jameel A; Afridi, Hassan I; Arain, Mariam S; Brahman, Kapil D; Naeemullah; Panhwar, Abdul H

    2015-06-01

    The aim of the current study is to evaluate the occurrence of arsenic in coal collected from Thar coalfield, Pakistan, and its behavior during the combustion. Fractionation of arsenic (As) in coal samples was carried out by Community Bureau of Reference sequential extraction scheme (BCR-SES) and single-step-based BCR method (BCR-SS). These methods are validated using the certified reference material of sediment BCR 701 and standard addition method. The stepwise fractions of As in laboratory-made ash (LMA) have been also investigated. The extractable As content associated with different phases in coal and LMA samples were analyzed by electrothermal atomic absorption spectrophotometer. The extraction efficiency of As by BCR-SS was slightly higher than BCR-SES, while the difference was not significant (p combustion of the coal, >85 % of As may be released into atmosphere. The relative mobility of As in the coal samples was found in increasing order as follows: oxidizable fraction coal samples of block III as compared to block V (p > 0.05).

  16. Effect of the Reburning Zone Stoichiometry on the Nox Concentration at the Three-Stage Combustion of Pulverized Coal

    Directory of Open Access Journals (Sweden)

    Chernetskaya Nelya

    2016-01-01

    Full Text Available Numerical study of heat and mass transfer taking into account the combustion of coal particles in the furnace at the three-stage combustion of pulverized coal was performed. Analysis of the reburning zone stoichiometry on the concentration of nitrogen oxides at the furnace outlet was made. The values of excess air in the primary and reburning combustion zones, providing for the concentration of nitrogen oxides at the furnace outlet is not more than 350 mg/m3 and unburned carbon not more than 1 % when burning coal with a high content of nitrogen were established.

  17. Qualitative analysis of coal combusted in boilers of the thermal power plants in Bosnia and Herzegovina

    Directory of Open Access Journals (Sweden)

    Đurić Slavko N.

    2012-01-01

    Full Text Available In this paper we have looked into the qualitative analysis of coals in Bosnia and Herzegovina (B-H. The analysis includes the following characteristics: moisture (W, ash (A, combustible matter (Vg and lower heating value (Hd. From the statistic parameters we have determined: absolute range (R, arithmetic mean (X, standard deviation (S and variations coefficient (Cv. It has been shown that the coal characteristics (W, A, Vg, Hd have normal distribution. The analysis show that there are considerable deviations of ash characteristics: moisture (36.23%, ash (34.21%, combustible matter (16.15% and lower heating value (25.16% from the mean value which is shown by the variations coefficient (Cv. Large oscilations of mass portions: W, A, Vg and Hd around the mean value can adversely influence the function of a boiler plant and an electric filter plant in thermal power plants in B-H in which the mentioned types of coal burn. Large ash oscilations (34.21% around the mean value point out to the inability of application of dry procedures of desulphurisation of smoke gasses (FGD due to the additional quantity of ash. It has been shown that the characteristics of Bosnian types of coal do not deviate a lot from the characteristics of coal in the surrounding countries (coals of Serbia and Monte Negro. The results can be used in analysis of coal combustion in thermal power plants, optimisation of electrical-filtre, reduction of SO2 in smoke gas and other practical problems.

  18. Innovative Clean Coal Technology (ICCT). Technical progress report, first quarter, 1993, January 1993--March 1993

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    The objective of this project is to demonstrate and evaluate commercially available Selective Catalytic Reduction (SCR) catalysts from U.S., Japanese and European catalyst suppliers on a high-sulfur U.S. coal-fired boiler. SCR is a post-combustion nitrogen oxide (NOx) control technology that involves injecting ammonia into the flue gas generated from coal combustion in an electric utility boiler. The flue gas containing ammonia is then passed through a reactor that contains a specialized catalyst. In the presence of the catalyst, the ammonia reacts with NOx to convert it to nitrogen and water vapor. Although SCR is widely practiced in Japan and Europe on gas-, oil-, and low-sulfur coal-fired boilers, there are several technical uncertainties associated with applying SCR to U.S. coals. These uncertainties include: (1) potential catalyst deactivation due to poisoning by trace metal species present in U.S. coals that are not present in other fuels; (2) performance of the technology and effects on the balance-of-plant equipment in the presence of high amounts of SO{sub 2} and SO{sub 3}; and (3) performance of a wide variety of SCR catalyst compositions, geometries and methods of manufacture under typical high-sulfur coal-fired utility operating conditions. These uncertainties will be explored by constructing a series of small-scale SCR reactors and simultaneously exposing different SCR catalysts to flue gas derived from the combustion of high sulfur U.S. coal. The demonstration will be performed at Gulf Power Company`s Plant Crist Unit No. 5 (75 NM capacity) near Pensacola, Florida. The project will be funded by the U.S. Department of Energy (DOE), Southern Company Services, Inc. (SCS on behalf of the entire Southern electric system), the Electric Power Research Institute (EPRI), and Ontario Hydro. SCS is the participant responsible for managing all aspects of this project.

  19. Tools for EU cleaner coal technologies

    Energy Technology Data Exchange (ETDEWEB)

    Luque Cabal, V. [European Commission, Directorate C - Conventional Energies, Unit C3 - Coal and Oil, Brussels (Belgium)

    2002-07-01

    27% of the European electricity demand are generated through the conversion of domestic primary energy sources. Therefore the Commission is of the opinion to guarantee a minimum production for coal. However, the challenge is the reduction of CO{sub 2} emissions resulting from coal combustion by taking into account the safety of energy supply. Within the scope of the 'European Programme to Climate Change' the increase of energy efficiency in conversion processes of solid fossil fuels was identified as one measure not resulting too high cost that might be able to contribute to the reduction of CO{sub 2} emissions by 2010. (orig.) [German] 27% der in Europa benoetigten Elektrizitaet werden durch heimische oder importierte feste Brennstoffe erzeugt. Daher haelt die EU-Kommission es fuer angebracht, der Kohle einen Mindestproduktionsanteil zu sichern. Dabei liegt die aktuelle Herausforderung in der Reduzierung der CO{sub 2}-Emissionen aus kohlebefeuerten Kraftwerken. Allerdings sollte dabei auch die Sicherheit der Energieversorgung beruecksichtigt werden. Der Anstieg der Energieeffizienz bei der Umwandlung fester Brennstoffe in Elektrizitaet wurde im Rahmen des 'Europaeischen Programms zur Klimaaenderung' (ECCP) als eine der Massnahmen benannt, die bis zum Jahre 2010 zur Verringerung der CO{sub 2}-Emissionen beitragen koennten und die nicht mit uebermaessigen Kosten verbunden waeren. (orig.)

  20. Computational fluid dynamics (CFD) analysis of the coal combustion in a boiler of a thermal power plant using different kinds of the manufactured coals

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Cristiano Vitorino da; Lazzari, Luis Carlos; Ziemniczak, Aline; Beskow, Arthur Bortolin [Universidade Regional Integrada do Alto Uruguai e das Missoes (URI), Erechim, RS (Brazil)], E-mails: cristiano@uricer.edu.br, arthur@uricer.edu.br

    2010-07-01

    The state of the art in computational fluid dynamics and the availability of commercial codes encourage numerical studies of combustion processes. In the present work the commercial software CFX Ansys Europe Ltd. has been used to study the combustion of pulverized coal into the boiler of a thermal power plant. The objective of this work is to obtain new information for process optimization. Different kinds of manufactured coals were numerically tested in a thermal power plant installed at the southeast region of Brazil. The simulations were made using the actual burning conditions of the boiler. Results include the residence time of the fuel into the combustion chamber, temperature fields, flow fluid mechanics, heat transfer and pollutant formation, as well as the CO and NOx concentrations, aiming to determinate the best conditions to burn the investigated coals. The numerical investigation of the phenomena involved on the coal combustion processes are used to complete the experimental information obtained in operational tests. Considering the characteristics of different kinds of manufactured coals used, with this study is possible to achieve the most efficient boiler operation parameters, with decreasing costs of electricity production and reduction of environmentally harmful emissions. It was verified that the different kinds of manufactured coals demand different operation conditions, and the kind of manufactured coal used on the combustion process has a significant effect on the pollutant formation, mainly in rel action with ash concentration. (author)

  1. Co-combustion of peach and apricot stone with coal in a bubbling fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Atimtay, Aysel T.; Kaynak, Burcak [Department of Environmental Engineering, Middle East Technical University, Ankara 06531 (Turkey)

    2008-02-15

    In this study a bubbling fluidized bed combustor (BFBC) having an inside diameter of 102 mm and a height of 900 mm was used to investigate the co-combustion characteristics of peach and apricot stones produced as a waste from the fruit juice industry with coal. A lignite coal was used for co-combustion. On-line concentrations of O{sub 2}, CO, CO{sub 2}, SO{sub 2}, NO{sub X} and total hydrocarbons (C{sub m}H{sub n}) were measured in the flue gas during combustion experiments. Variations of emissions of various pollutants were studied by changing the operating parameters (excess air ratio, fluidization velocity, and fuel feed rate). Temperature distribution along the bed was measured with thermocouples. For co-combustion of apricot and peach fruit stones with a lignite coal, various ratios of biomass to coal ranging from 0 to 100 wt.% were tested. For the peach stone co-combustion tests, efficiencies are about 98% and for the apricot stone co-combustion tests, efficiencies ranged between 94.7% and 96.9% for 25%, 50% and 75% of apricot stone in the fuel mixture. The results of this study have shown that as the biomass ratio in the fuel mixture increases, the combustion takes place at the upper regions of the main column. This causes higher temperatures in the freeboard than the bed. Also the CO and hydrocarbon (C{sub m}H{sub n}) emissions increase as the biomass percentage increases in the fuel mixture. This causes decrease in the combustion efficiency. These results suggest that peach and apricot stones are potential fuels that can be utilized for clean energy production in small-scale fruit juice industries by using BFBC. The percentage of peach stones or apricot stones in the fuel mixture is suggested to be below 50 wt.% in order to obtain the emission limits of EU. During the design of the BFBC, one has to be careful about the volatile matter (VM) content of the biomass. For the complete combustion of the VM, longer freeboard or secondary air addition should be

  2. Comprehensive Mathematical Model for Coal Combustion in a Circulating Fluidized Bed Combustor

    Institute of Scientific and Technical Information of China (English)

    金晓钟; 吕俊复; 杨海瑞; 刘青; 岳光溪; 冯俊凯

    2001-01-01

    Char combustion is on a special reducing condition in the dense bed of a circulating fluidized bedcombustor. Experimental findings were used to develop a comprehensive mathematical model to simulate thehydrodynamic and combustion processes in a circulating fluidized bed combustor. In the model, gas-solidinteraction was used to account for the mass transfer between the bubble phase and the emulsion phase in thedense bed, which contributes to the reducing atmosphere in the dense bed. A core-annular structure wasassumed in the dilute area rather than a one-dimensional model. The submodels were combined to build thecomprehensive model to analyze the combustion in a circulating fluidized bed combustor and the effect ofoperating parameters on the coal combustion. The model predictions agree well with experimental results.

  3. Measurement of O2 in the Combustion Chamber of Apulverized Coal Boiler

    Directory of Open Access Journals (Sweden)

    Břetislav Janeba

    2012-01-01

    Full Text Available Operational measurements of the O2 concentration in the combustion chamber of a pulverized coal boiler are not yet common practice. Operators are generally satisfied with measuring the O2 concentration in the second pass of the boiler, usually behind the economizer, where a flue gas sample is extracted for analysis in a classical analyzer. A disadvantage of this approach is that there is a very weak relation between the measured value and the condition in specific locations in the fireplace, e.g. the function of the individual burners and the combustion process as a whole. A new extractionline was developed for measuring the O2 concentration in the combustion chamber. A planar lambda probe is used in this approach. The extraction line is designed to get outputs that can be used directly for diagnosis or management of the combustion in the boiler.

  4. Flame radiant image numeralization for pulverized coal combustion in BF raceway

    Institute of Scientific and Technical Information of China (English)

    WEN Liang-ying; OU Yang-qi; BAI Chen-guang; WANG Hua

    2005-01-01

    In order to establish correlativity between pulverized coal combustion in a blast furnace raceway and its radiant image, we investigated the relationships between two dimensional radiant images and three dimensional radiant energy in a blast furnace raceway, focusing on the correlativity of the numerical simulation of combustion processes with the connection of radiant images information and space temperature distribution. We calculated the uneven radiate characteristic parameterby taking radiant images as a kind of radiative boundary for numerical simulation of combustion processes, and put forward a method to examine three-dimensional temperatures distribution in blast furnace raceway by radiant image processing. The numeral temperature fields matching the real combustion can be got by the numeric image processing technique.

  5. Assessing coal combustion and sourcing strategies using EPRI`s CQIM{sup {trademark}}

    Energy Technology Data Exchange (ETDEWEB)

    Stallard, G.S.; Jennison, K.D. [Black & Veatch, Overland Park, KS (United States)

    1995-12-01

    Understanding the cost and performance issues associated with coal quality or, more precisely, specific constituents within coal is an important ingredient of engineering and planning processes. Such processes can cover a wide range of activities, including how to most cost-effectively burn local coal supplies, how to identify what technologies or designs should be employed for new facilities, and how to identify potentially viable {open_quotes}new{close_quotes} coal supplies. Selection of coals, coal blends, or coal benefication processes is a complex problem. Similarly, it is difficult for industry participants (ministries, regulators, distribution companies, etc.) To correlate fuel selection strategies to overall power system performance costs. The underlying need to understand coal quality impacts on the financial efficiency of a plant is increasingly important in light of economic and environmental pressures faced by today`s power industry. The Coal Quality Impact Model (CQIM{reg_sign}) offers an ideal platform for understanding and evaluating coal quality impacts. Developed by Black & Veatch for the electric Power Research Institute (EPRI), CQIM is a computer {open_quotes}tool{close_quotes} that is dedicated to maintaining state-of-the-art status by continually incorporating the latest technologies or modeling techniques as they become available. By taking advantage of research efforts and a sound engineering modeling approach, the CQIM is capable of predicting plant-wide performance impacts and translating them into costs.

  6. Char crystalline transformations during coal combustion and their implications for carbon burnout

    Energy Technology Data Exchange (ETDEWEB)

    Hurt, R.H.

    1999-03-11

    Residual, or unburned carbon in fly ash affects many aspects of power plant performance and economy including boiler efficiency, electrostatic precipitator operation, and ash as a salable byproduct. There is a large concern in industry on the unburned carbon problem due to a variety of factors, including low-NOx combustion system and internationalization of the coal market. In recent work, it has been found that residual carbon extracted from fly ash is much less reactive than the laboratory chars on which the current kinetics are based. It has been suggested that thermal deactivation at the peak temperature in combustion is a likely phenomenon and that the structural ordering is one key mechanism. The general phenomenon of carbon thermal annealing is well known, but there is a critical need for more data on the temperature and time scale of interest to combustion. In addition, high resolution transmission electron microscopy (HRTEM) fringe imaging, which provides a wealth of information on the nature and degree of crystallinity in carbon materials such as coal chars, has become available. Motivated by these new developments, this University Coal Research project has been initiated with the following goals: to determine transient, high-temperature, thermal deactivation kinetics as a function of parent coal and temperature history; and to characterize the effect of this thermal treatment on carbon crystalline structure through high-resolution transmission electron microscopy and specialized, quantitative image analysis.

  7. Char crystalline transformations during coal combustion and their implications for carbon burnout

    Energy Technology Data Exchange (ETDEWEB)

    Hurt, R.H.

    1999-07-07

    Residual, or unburned carbon in fly ash affects many aspects of power plant performance and economy including boiler efficiency, electrostatic precipitator operation, and ash as a salable byproduct. There is a large concern in industry on the unburned carbon problem due to a variety of factors, including low-NOx combustion system and internationalization of the coal market. In recent work, it has been found that residual carbon extracted from fly ash is much less reactive than the laboratory chars on which the current kinetics are based. It has been suggested that thermal deactivation at the peak temperature in combustion is a likely phenomenon and that the structural ordering is one key mechanism. The general phenomenon of carbon thermal annealing is well known, but there is a critical need for more data on the temperature and time scale of interest to combustion. In addition, high resolution transmission electron microscopy (HRTEM) fringe imaging, which provides a wealth of information on the nature and degree of crystallinity in carbon materials such as coal chars, has become available. Motivated by these new developments, this University Coal Research project has been initiated with the following goals: (1) To determine transient, high-temperature, thermal deactivation kinetics as a function of parent coal and temperature history. (2) To characterize the effect of the thermal treatment on carbon crystalline structure through high-resolution transmission electron microscopy and specialized, quantitative image analysis.

  8. 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.

  9. Coal-water-slurry evaluation. Volume 2. Laboratory and combustion test results. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Daley, R.D.; Farthing, G.A.; Vecci, S.J.

    1984-02-01

    This is the second of three volumes describing a multi-phase coal-water slurry (CWS) test program. This volume presents the results of laboratory, atomization, and combustion tests which were performed on six slurries and their parent coals. The objectives of these tests was to establish laboratory test procedures for evaluating CWS fuels, to investigate relationships between laboratory properties and CWS combustion and handling characteristics and to develop preliminary guidelines for CWS specifications. These tests showed that the preparation processes and chemical additives used by the slurry manufacturers had a significant effect on viscosity and atomization properties. The most important factor for good combustion performance was droplet size, but droplet size did not correlate with viscosity measured at low shear rates in the laboratory tests. It was also found that some slurries had greater fouling potential than their parent coals due to the use of sodium-containing additives. Tests were also conducted to determine whether the slurries could be transported and stored without coal settling. These tests showed that little settling occurred during either transportation or storage for at least three weeks. 98 figures, 27 tables.

  10. Directions of changes of hard coal output technologies in Poland

    Institute of Scientific and Technical Information of China (English)

    Turek Marian

    2011-01-01

    The author presents the results being the effect of the analysis of innovative rate of individual technologies applied in opening up, development and extraction works which was carried out within the project: "scenarios of technological development of hard coal extractive industry". After presentation of opening up, development and extraction technologies that are applied in Polish hard coal industry and their classification with regard to innovation degree the author describes those technologies in a detailed manner. He brings attention to the most effective systems for hard coal deposits' opening up, development and their extraction, including the extraction of the residual coal. The attention is also paid to the safety level of the applied technologies.

  11. Chemical and toxicological characterization of organic constituents in fluidized-bed and pulverized coal combustion: a topical report

    Energy Technology Data Exchange (ETDEWEB)

    Chess, E.K.; Later, D.W.; Wilson, B.W.; Harris, W.R.; Remsen, J.F.

    1984-04-01

    Coal combustion fly ash from both conventional pulverized coal combustion (PCC) and fluidized-bed combustion (FBC) have been characterized as to their organic constituents and microbial mutagenic activity. The PCC fly ash was collected from a commercial utility generating plant using a low sulfur coal. The FBC fly ash was from a bench-scale developmental unit at the Grand Forks Energy Technology Center. Bulk samples of each fly ash were extracted using benzene/methanol and further separated using high performance liquid chromatography (HPLC). Subfractions from the HPLC separation were analyzed by gas chromatography using both element-specific nitrogen-phosphorus detectors and flame ionization detectors. Microbial mutagenicity assay results indicated that the crude organic extracts were mutagenic, and that both the specific activity and the overall activity of the PCC material was greater than that of the FBC material. Comparison of results from assays using S. typhimurium, TA1538NR indicated that nitrated polycyclic aromatic compounds (PAC) were responsible for much of the mutagenic activity of the PCC material. Similar results were obtained for assays of the FBC organic extract with standard and nitroreductase-deficient strains of S. typhimurium, TA100 and TA1538. Mutagenically active HPLC fractions were analyzed using high resolution gas chromatography (HRGC) and GC mass spectrometry (GC/MS), as well as probe inlet low and high resolutions MS. The discovery and identification of nitrated, oxygenated PAC are important because the presence of both nitro and/or keto functionalities on certain PAC has been shown to confer or enhance mutagenic activity.

  12. Combustion characteristics of pulverized coal and air/gas premixed flame in a double swirl combustor

    Energy Technology Data Exchange (ETDEWEB)

    Kamal, M.M. [Ain Shams University, Cairo (Egypt). Faculty of Education

    2009-07-01

    An experimental work was performed to investigate the co-firing of pulverized coal and premixed gas/air streams in a double swirl combustor. The results showed that the NOx emissions are affected by the relative rates of thermal NOx formation and destruction via the pyrolysis of the fuel-N species in high temperature fuel-rich zones. Various burner designs were tested in order to vary the temperature history and the residence time across both coal and gas flames inside the furnace. It was found that by injecting the coal with a gas/air mixture as a combined central jet surrounded by a swirled air stream, a double flame envelope develops with high temperature fuel-rich conditions in between the two reaction zones such that the pyrolysis reactions to N{sub 2} are accelerated. A further reduction in the minimum NOx emissions, as well as in the minimum CO concentrations, was reported for the case where the coal particles are fed with the gas/air mixture in the region between the two swirled air streams. On the other hand, allocating the gas/air mixture around the swirled air-coal combustion zone provides an earlier contact with air and retards the NOx reduction mechanism in such a way that the elevated temperatures around the coal particles allow higher overall NOx emissions. The downstream impingement of opposing air jets was found more efficient than the impinging of particle non-laden premixed flames for effective NOx reduction. In both cases, there is an upstream flow from the stagnation region to the coal primary combustion region, but with the case of air impingement, the hot fuel-rich zone develops earlier. The optimum configuration was found by impinging all jets of air and coal-gas/air mixtures that pronounced minimum NOx and CO concentrations of 310 and 480ppm, respectively.

  13. Co-combustion of pulverized coal and solid recovered fuel in an entrained flow reactor- General combustion and ash behavior

    DEFF Research Database (Denmark)

    Wu, Hao; Glarborg, Peter; Frandsen, Flemming

    2011-01-01

    .9 wt.%, 14.8 wt.% and 25 wt.%, respectively. The effect of additives was evaluated by maintaining the share of secondary fuel (mixture of SRF and additive) at 14.8 wt.%. The experimental results showed that the fuel burnout, NO and SO2 emission in co-combustion of coal and SRF were decreased...... with increasing share of SRF. The majority of the additives inhibited the burnout, except for NaCl which seemed to have a promoting effect. The impact of additives on NO emission was mostly insignificant, except for ammonium sulphate which greatly reduced the NO emission. For SO2 emission, it was found that all...

  14. Mercury and Air Toxic Element Impacts of Coal Combustion By-Product Disposal and Utilizaton

    Energy Technology Data Exchange (ETDEWEB)

    David Hassett; Loreal Heebink; Debra Pflughoeft-Hassett; Tera Buckley; Erick Zacher; Mei Xin; Mae Sexauer Gustin; Rob Jung

    2007-03-31

    The University of North Dakota Energy & Environmental Research Center (EERC) conducted a multiyear study to evaluate the impact of mercury and other air toxic elements (ATEs) on the management of coal combustion by-products (CCBs). The ATEs evaluated in this project were arsenic, cadmium, chromium, lead, nickel, and selenium. The study included laboratory tasks to develop measurement techniques for mercury and ATE releases, sample characterization, and release experiments. A field task was also performed to measure mercury releases at a field site. Samples of fly ash and flue gas desulfurization (FGD) materials were collected preferentially from full-scale coal-fired power plants operating both without and with mercury control technologies in place. In some cases, samples from pilot- and bench-scale emission control tests were included in the laboratory studies. Several sets of 'paired' baseline and test fly ash and FGD materials collected during full-scale mercury emission control tests were also included in laboratory evaluations. Samples from mercury emission control tests all contained activated carbon (AC) and some also incorporated a sorbent-enhancing agent (EA). Laboratory release experiments focused on measuring releases of mercury under conditions designed to simulate CCB exposure to water, ambient-temperature air, elevated temperatures, and microbes in both wet and dry conditions. Results of laboratory evaluations indicated that: (1) Mercury and sometimes selenium are collected with AC used for mercury emission control and, therefore, present at higher concentrations than samples collected without mercury emission controls present. (2) Mercury is stable on CCBs collected from systems both without and with mercury emission controls present under most conditions tested, with the exception of vapor-phase releases of mercury exposed to elevated temperatures. (3) The presence of carbon either from added AC or from unburned coal can result in mercury

  15. Combustion of agro-waste with coal in a fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Atimtay, Aysel T. [Middle East Technical University, Department of Environmental Engineering, Ankara (Turkey)

    2010-02-15

    In this study, a review of the studies done on the co-combustion of some agro-waste in a bubbling fluidized bed combustor (BFBC) having an inside diameter of 102 mm and a height of 900 mm is given. The agro-waste used to investigate the co-combustion chara