Science.gov

Sample records for assessing coal combustion

  1. Coal combustion science

    SciTech Connect

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

    1990-11-01

    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 (PETC) Direct Utilization Advanced Research and Technology Development Program, and the International Energy Agency (IEA) Coal Combustion Science Project. Specific tasks include: coal devolatilization, coal char combustion, and fate of mineral matter during coal combustion. 91 refs., 40 figs., 9 tabs.

  2. Toxic substances form coal combustion--a co prehemsice assessment

    SciTech Connect

    Huggins, F.; Huffman, G.P.; Shah, N.

    1997-04-01

    The Clean Coal Act Amendments of 1990 identify a number of hazardous air pollutants as candidates for regulation. Should regulations be imposed on emission of these pollutants from coal-fired power plants, a sound understanding of the fundamental principles controlling their formation and partition will be needed. A new Toxics Partitioning Engineering Model (ToPEM) has been developed by a broad consortium to be useful to regulators and utility planners. During the last quarter coal analysis was completed on the final program coal, from the Wyodak Seam of the Powder River Basin, Combustion testing continued, including data collected on the self-sustained combustor. Efforts were directed to identify the governing mechanisms for trace element vaporization from the program coals. Mercury speciation and measurements were continued. Review of the existing trace element and organics emission literature was completed. And, model development was begun.

  3. TOXIC SUBSTANCES FROM COAL COMBUSTION: A COMPREHENSIVE ASSESSMENT

    SciTech Connect

    C.L. Senior; T. Panagiotou; J.O.L. Wendt; W. Seames; F.E. Huggins; G.P Huffman; N. Yap; M.R. Ames; I.Olmez; T. Zeng; A.F. Sarofim; A. Kolker; R. Finkelman; J.J. Helble

    1998-07-16

    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, the Massachusetts Institute of Technology (MIT), the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (W) 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{sub x} 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 the submission of the draft Phase 1 Final Report through the end of June, 1998. During this period two of the three Phase 2 coals were procured and pulverized samples were distributed to team members. Analysis of Phase 1 X-Ray Absorption Fine Structure (XAFS) data, particularly of mercury in sorbent samples, continued. An improved method for identifying mercury compounds on sorbents was developed, leading to a clearer understanding of forms of mercury in char and sorbents exposed to flue gas. Additional analysis of Phase 1 large scale combustion data was performed to investigate mechanistic information related to the fate of the radionuclides Cs, Th, and Co. Modeling work for this period was focused on building and testing a sub-model for vaporization

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

    SciTech Connect

    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

  5. TOXIC SUBSTANCES FROM COAL COMBUSTION A COMPREHENSIVE ASSESSMENT

    SciTech Connect

    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

  6. TOXIC SUBSTANCES FROM COAL COMBUSTION-A COMPREHENSIVE ASSESSMENT

    SciTech Connect

    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 UU

  7. Coal combustion products

    USGS Publications Warehouse

    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.

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

    SciTech Connect

    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 preparation

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

    EPA Science Inventory

    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.

  10. Coal Combustion Science

    SciTech Connect

    Hardesty, D.R.; Fletcher, T.H.; Hurt, R.H.; Baxter, L.L. )

    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.

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

    SciTech Connect

    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.

  12. Assessment of mercury health risks to adults from coal combustion

    SciTech Connect

    Lipfert, F.W.; Moskowitz, P.D.; Fthenakis, V.M.; DePhillips, M.P.; Viren, J.; Saroff, L.

    1994-05-01

    The U.S. Environmental Protection Agency (EPA) is preparing, for the U.S. Congress, a report evaluating the need to regulate mercury (Hg) emissions from electric utilities. This study, to be completed in 1995, will have important health and economic implications. In support of these efforts, the U.S. Department of Energy, Office of Fossil Energy, sponsored a risk assessment project at Brookhaven National Laboratory (BNL) to evaluate methylmercury (MeHg) hazards independently. In the BNL study, health risks to adults resulting from Hg emissions from a hypothetical 1000 MW{sub e} coal-fired power plant were estimated using probabilistic risk assessment techniques. The approach draws on the extant knowledge in each of the important steps in the calculation chain from emissions to health effects. Estimated results at key points in the chain were compared with actual measurements to help validate the modeled estimates. Two cases were considered: the baseline case (no local impacts), and the impact case (maximum local power-plant impact). The BNL study showed that the effects of emissions of a single power plant may double the background exposures to MeHg resulting from consuming fish obtained from a localized area near the power plant. Many implicit and explicit sources of uncertainty exist in this analysis. Those that appear to be most in need of improvement include data on doses and responses for potentially sensitive subpopulations (e.g., fetal exposures). Rather than considering hypothetical situations, it would also be preferable to assess the risks associated with actual coal-fired power plants and the nearby sensitive water bodies and susceptible subpopulations. Finally, annual total Hg emissions from coal burning and from other anthropogenic sources are still uncertain; this makes it difficult to estimate the effects of U.S. coal burning on global Hg concentration levels, especially over the long term.

  13. ENVIRONMENTAL ASSESSMENT OF THE FLUIDIZED-BED COMBUSTION OF COAL: METHODOLOGY AND INITIAL RESULTS

    EPA Science Inventory

    The paper discusses a program being conducted by the U.S. Environmental Protection Agency (EPA), aimed at complete environmental assessment (EA) of the fluidized-bed combustion (FBC) of coal. It reviews the EA methodology being developed by EPA: identification of current technolo...

  14. WASTE AND WATER MANAGEMENT FOR CONVENTIONAL COAL COMBUSTION ASSESSMENT REPORT - 1979; VOLUME II. WATER MANAGEMENT

    EPA Science Inventory

    The report, the second of five volumes, describes water management for conventional combustion sources and assesses the current status of various studies and programs in water management and trends in water recycle/reuse. A coal-fired boiler produces both chemical and thermal pol...

  15. The value of coal combustion products: an economic assessment of CCP unitization for the US economy

    SciTech Connect

    Steward, A.

    2005-07-01

    The recently released study by the American Coal Council (ACC) on 'The Value of Coal Combustion Products' provides a detailed economic assessment of CCP utilization for US markets and the US economy. Over 125 million tons of CCPs are produced in the US each year. The projected growth in the nation's utility-coal industry will result in the production of even greater volumes of CCPs. The ACC study details: how CCPs are currently being utilized; what factors are affecting utilization growth; what are the economic benefits of avoiding disposal costs; what is the annual revenue potential of CCP utilization; what direct economic benefits in employment and tax revenues can be gained; and what indirect economic benefits are available for support industries, coal consumers and the building industry. 9 refs., 16 tabs.

  16. Environmentally conscious coal combustion

    SciTech Connect

    Hickmott, D.D.; Brown, L.F.; Currier, R.P.

    1997-08-01

    This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of this project was to evaluate the environmental impacts of home-scale coal combustion on the Navajo Reservation and develop strategies to reduce adverse health effects associated with home-scale coal combustion. Principal accomplishments of this project were: (1) determination of the metal and gaseous emissions of a representative stove on the Navajo Reservation; (2) recognition of cyclic gaseous emissions in combustion in home-scale combustors; (3) `back of the envelope` calculation that home-scale coal combustion may impact Navajo health; and (4) identification that improved coal stoves require the ability to burn diverse feedstocks (coal, wood, biomass). Ultimately the results of Navajo home-scale coal combustion studies will be extended to the Developing World, particularly China, where a significant number (> 150 million) of households continue to heat their homes with low-grade coal.

  17. Coal combustion system

    DOEpatents

    Wilkes, Colin; Mongia, Hukam C.; Tramm, Peter C.

    1988-01-01

    In a coal combustion system suitable for a gas turbine engine, pulverized coal is transported to a rich zone combustor and burned at an equivalence ratio exceeding 1 at a temperature above the slagging temperature of the coal so that combustible hot gas and molten slag issue from the rich zone combustor. A coolant screen of water stretches across a throat of a quench stage and cools the combustible gas and molten slag to below the slagging temperature of the coal so that the slag freezes and shatters into small pellets. The pelletized slag is separated from the combustible gas in a first inertia separator. Residual ash is separated from the combustible gas in a second inertia separator. The combustible gas is mixed with secondary air in a lean zone combustor and burned at an equivalence ratio of less than 1 to produce hot gas motive at temperature above the coal slagging temperature. The motive fluid is cooled in a dilution stage to an acceptable turbine inlet temperature before being transported to the turbine.

  18. Coal combustion research

    SciTech Connect

    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.

  19. Toxic Substances from Coal Combustion: A Comprehensive Assessment: Quarterly report, 1 July 1996-30 September 1996

    SciTech Connect

    Bool, L.E.; Senior, C.L.; Huggins, F.; Huffman, G.P.; Shah, N.; Wendt, J.O.L.; Peterson, T.W.; Sarofim, A.F.; Olmez, I.; Zeng, T.; Crowley, S.; Finkelman, R.

    1996-10-01

    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 Pittsburgh Energy Technology Center (PETC), the Electric Power Research Institute (EPRI), and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UKy), the University of Connecticut, and Princeton University 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{sub x}, combustion systems, and new power generation plants. Development of ToPEM will be based on PSI`s existing Engineering Model for Ash Formation (EMAF). Extensive coal characterization and laboratory work has begun in order to develop and test new sub-models. Trace element concentrations in the Pittsburgh, Elkhorn/Hazard, and Illinois No. 6 coals, and in size/density fractions of these coals, were completed. Coal characterization in the past quarter also included direct identification of the modes of occurrence of various trace inorganic species in coal and ash using unique analytical techniques such as XAFS analysis and selective leaching. Combustion testing of these two coals was begun and preliminary data obtained on trace element 0301 vaporization in the combustion zone. Modeling efforts in the past quarter include the development on a preliminary model to assess mercury speciation in combustion systems.

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

    EPA Science Inventory

    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...

  1. Assessment of the effect of high ash content in pulverized coal combustion

    SciTech Connect

    Jayanti, S.; Maheswaran, K.; Saravanan, V.

    2007-05-15

    The existing literature on CFD-based coal combustion modelling is applicable mainly for coals of low ash content and the calculations are done on an ash-free basis. In Indian coals, the ash content may be significantly higher, up to 40% or more. Studies reported in the literature show that the mineral matter in the coal may have a number of effects on the combustion characteristics. In the present study, a sensitivity analysis is performed, using the CFD code CFX of AEA Technology, on the likely effect of ash content on the char reactivity, oxygen diffusion rate for char combustion and on the radiative heat transfer parameters. The results show that the effect of enhanced char reactivity is negligible whereas reduced oxygen diffusion rates due to a thicker ash layer may result in a significant reduction in char oxidation rates with a resultant decrease in the peak temperature in the furnace. The global parameters such as the peak temperature and the flue gas temperature remain relatively insensitive to the presence of high ash content. These results are consistent with the experimental observations of Kurose et al. . Kurose, M. Ikeda, H. Makino, Combustion characteristics of high ash coal in pulverized coal combustion, J. Fuel 80 (2001) 1447-1455).

  2. Toxic substances from coal combustion -- A comprehensive assessment. Quarterly report, October 1, 1996--December 31, 1996

    SciTech Connect

    Bool, L.E. III; Senior, C.L.; Huggins, F.; Huffman, G.P.; Shah, N.

    1997-01-31

    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 (UKy), the University of Connecticut, and Princeton University 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). During the past quarter the final program coal, from the Wyodak seam in the Powder River Basin, was acquired and distributed. Extensive coal characterization and laboratory work is underway to develop and test new sub-models. Coal characterization in the past quarter included direct identification of the modes of occurrence of various trace inorganic species in coal and ash using unique analytical techniques such as XAFS analysis and selective leaching. Combustion testing of the bituminous coals continued and additional data were obtained on trace element vaporization in the combustion zone. Studies of post-combustion trace element transformations, such as mercury speciation in the flue gas, were also begun in the last quarter.

  3. COMBUSTION OF HYDROTHERMALLY TREATED COALS

    EPA Science Inventory

    The report gives results of an evaluation of: (1) the relationship of the combustion characteristics of hydrothermally treated (HTT) coals to environmental emissions, boiler design, and interchangeability of solid fuels produced by the Hydrothermal Coal Process (HCP) with raw coa...

  4. PRELIMINARY ENVIRONMENTAL ASSESSMENT OF COAL-FIRED FLUIDIZED-BED COMBUSTION SYSTEMS

    EPA Science Inventory

    The report evaluates potential pollutants which could be generated in coal-fired fluidized-bed combustion (FBC) processes. The primary emphasis is on organic compounds, trace elements, inorganic compounds (other than SO2 and Nox), and particulates. Using available bench scale or ...

  5. Coal char fragmentation during pulverized coal combustion

    SciTech Connect

    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.

  6. TOXIC SUBSTANCES FROM COAL COMBUSTION--A COMPREHENSIVE ASSESSMENT, PHASE II: ELEMENT MODES OF OCCURRENCE FOR THE OHIO 5/6/7, WYODAK AND NORTH DAKOTA COAL SAMPLES

    SciTech Connect

    Allan Kolker; Stanley J. Mroczkowski; Curtis A. Palmer; Kristen O. Dennen; Robert B. Finkelman; John H. Bullock Jr.

    2002-05-30

    This study reports on the second phase (Phase II) of USGS research activities in support of DOE contract DE-AC22-95PC95101 ''Toxic Substances From Coal Combustion--A Comprehensive Assessment'', funded under DOE Interagency Agreement DE-AI22-95PC95145. The purpose of the study was to provide a quantitative and semi-quantitative characterization of the modes of occurrence of trace elements in coal samples investigated under Phase II, including (1) Ohio 5/6/7, an Ohio bituminous coal sample blended from the No.5, No.6, and No.7 beds; (2) North Dakota, a lignite sample from the Falkirk Mine, Underwood, ND, and (3) Wyodak, a sub-bituminous coal sample from the Cordero Mine, Gillette, WY. Samples from these coal beds were selected for their range in rank and commercial applicability. Results of this research provide basic information on the distribution of elements in Phase II coal samples, information needed for development of a commercial predictive model for trace-element behavior during coal combustion.

  7. Catalyzing the Combustion of Coal

    NASA Technical Reports Server (NTRS)

    Humphrey, M. F.; Dokko, W.

    1982-01-01

    Reaction rate of coal in air can be increased by contacting or coating coal with compound such as calcium acetate. The enhanced reaction rate generates more heat, reducing furnace size. Increase in combustion rate is about 26 percent, and internal pollutants in powerplant are reduced.

  8. Fluidized bed combustion of coal

    NASA Astrophysics Data System (ADS)

    Tatebayashi, J.; Okada, Y.; Yano, K.; Takada, T.; Handa, K.

    The effect of various parameters on combustion efficiency, desulfurization efficiency and NO emission in fluidized bed combustion of coal were investigated by using two test combustors whose sectional areas were 200 mm and 500 mm square. It has been revealed that by employing two-stage combustion and setting the primary air ratio, secondary air injection height and other parameters to optimum levels, NO emission can be greatly reduced while barely impairing combustion efficiency or desulfurization efficiency. Also, NO emission of less than 50 ppm and desulfurization efficiency of as high as 93% were achieved. These results have ensured good prospects for the development of a coal combustion boiler system which can satisfy the strictest environmental protection regulations, without installing special desulfurization and de-NO(X) facilities.

  9. Assessment of PAH toxicity and mutagenicity in emissions from coal and biofuel combustion.

    PubMed

    Rajput, Nirat; Pyari, A Anand; Saini, Manoj K; Kumari, K Maharaj; Lakhani, Anita

    2010-07-01

    Emissions from combustion of coal, wood and cowdung cakes in domestic cookstoves were sampled through a Stack Monitor on Glass Fibre thimbles. 16 PAH compounds were quantified in the samples extracted in dichloromethane by Gas Chromatography using FID detector. The toxic potencies of the quantified PAHs were determined by Toxicity Equivalence (TEF) Approach and their mutagenecities were tested by using Ames Plate Incorporation Method. All the 16 PAHs were determined in the emission of wood, including genotoxic compounds: carcinogens (BaA, Chy, BbF, BkF, BaP, DbA and IP) and co-carcinogens (Fla, Pyr, BghiP). In coal smoke, only 12 compounds were detected, while in cowdung cake 15 PAHs were detected except Phenanthrene. Emission factors on a fuel weight basis are highest for cowdung cake (120.23 mg/kg), followed by wood (48.97 mg/kg) and coal (28.85 mg/kg). Most of the contribution to the total PAH concentrations was from the high molecular weight compounds. Considering the genotoxic PAHs, the emission factor ranking order was from cow dung cake (115.85 mg/kg) to wood (43.03 mg/kg) and lowest for coal fuel (25.97 mg/kg). The emission factor for BaP was highest for cowdung cake (78.83 mg/kg) followed by coal (5.53 mg/kg) and wood fuel (4.47 mg/kg). Calculation of toxic potencies reveals that the carcinogenic contribution from low molecular weight PAHs is relatively much lower than high molecular weight PAHs for each tested fuel. Cow dung cake extracts did not show mutagenic activity in the Ames Salmonella test probably due to lower concentration of the direct-mutagens like Pyr, Chy. In contrast, the extracts of coal and wood had higher concentrations of direct-mutagens like Pyr, Chy, so positive results were obtained. PMID:21391389

  10. Assessment of pulverized-coal-fired combustion performance: Final report for the period September 1980--September 1983

    SciTech Connect

    Richter, W.F.; Clark, W.; Pohl, J.H.; Payne, R.

    1987-06-01

    The purpose of this program was to evaluate an engineering analysis procedure which could be used to assess the impact on thermal performance of converting gas and oil fired equipment to coal. The program consisted of four major tasks: (1) Engineering Analysis. The objective was to evaluate currently available models which could be used to predict combustor performance and to define a procedure which could be used to assess the impact of a coal firing in a boiler or furnace; (2) Reactor Studies. The purpose was to evaluate, under controlled conditions, the radiative properties of fly ash clouds; (3) Pilot Scale Experiments. This involved a combustion trial with gas and coals which were burned at 0.7 /times/ 10/sup 6/ Btu/hr in a pilot-scale combustor. The purpose was to verify and supplement the results of the small-scale reactor studies on the radiant properties of coal flames at larger scale; (4) Reporting. Engineering analysis procedures were used to identify those fuels related properties which had a major impact on the thermal performance of furnaces. The major result of the study is that thermal performance of coal-fired furnaces is dominated by the formation of fly ash deposits on the heat transfer surfaces. The key parameters which influence thermal performance are: thickness, thermal conductivity, and surface emissivity or absorptivity. 105 refs., 170 figs., 29 tabs.

  11. Assessment of groundwater quality impacts due to use of coal combustion byproducts to control subsidence from underground mines.

    PubMed

    Singh, G; Paul, B C

    2001-06-01

    Coal combustion byproducts are to be placed in an underground coal mine to control subsidence. The materials were characterized to determine potential groundwater impacts. No problems were found with respect to heavy or toxic metals. Coal combustion byproduct leachates are high in dissolved solids and sulfates. Chloride and boron from fly ash may also leach in initially high concentrations. Because the demonstration site is located beneath deep tight brine-bearing aquifers, no problems are anticipated at the demonstration site. PMID:11485225

  12. Oxy-coal Combustion Studies

    SciTech Connect

    Wendt, J.; Eddings, E.; Lighty, J.; Ring, T.; Smith, P.; Thornock, J.; Y Jia, W. Morris; Pedel, J.; Rezeai, D.; Wang, L.; Zhang, J.; Kelly, K.

    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.

  13. NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    SciTech Connect

    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.

  14. Nitrogen release during coal combustion

    SciTech Connect

    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.

  15. Coal combustion by wet oxidation

    SciTech Connect

    Bettinger, J.A.; Lamparter, R.A.; McDowell, D.C.

    1980-11-15

    The combustion of coal by wet oxidation was studied by the Center for Waste Management Programs, of Michigan Technological University. In wet oxidation a combustible material, such as coal, is reacted with oxygen in the presence of liquid water. The reaction is typically carried out in the range of 204/sup 0/C (400/sup 0/F) to 353/sup 0/C (650/sup 0/F) with sufficient pressure to maintain the water present in the liquid state, and provide the partial pressure of oxygen in the gas phase necessary to carry out the reaction. Experimental studies to explore the key reaction parameters of temperature, time, oxidant, catalyst, coal type, and mesh size were conducted by running batch tests in a one-gallon stirred autoclave. The factors exhibiting the greatest effect on the extent of reaction were temperature and residence time. The effect of temperature was studied from 204/sup 0/C (400/sup 0/F) to 260/sup 0/C (500/sup 0/F) with a residence time from 600 to 3600 seconds. From this data, the reaction activation energy of 2.7 x 10/sup 4/ calories per mole was determined for a high-volatile-A-Bituminous type coal. The reaction rate constant may be determined at any temperature from the activation energy using the Arrhenius equation. Additional data were generated on the effect of mesh size and different coal types. A sample of peat was also tested. Two catalysts were evaluated, and their effects on reaction rate presented in the report. In addition to the high temperature combustion, low temperature desulfurization is discussed. Desulfurization can improve low grade coal to be used in conventional combustion methods. It was found that 90% of the sulfur can be removed from the coal by wet oxidation with the carbon untouched. Further desulfurization studies are indicated.

  16. Oxy Coal Combustion at the US EPA

    EPA Science Inventory

    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...

  17. Reduction of spontaneous combustion of coal

    SciTech Connect

    Burns, E.J.

    1982-05-25

    A composition for the prevention of spontaneous combustion of coal is described which is comprised of at least about 2 percent of polyethylene oxide and the balance water. Also described is a method for reducing the spontaneous combustion tendency of coal by contacting coal with the above composition and then drying the coal.

  18. Atmospheric fluidized-bed combustion (AFBC) co-firing of coal and hospital waste. Environmental Assessment

    SciTech Connect

    Not Available

    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.

  19. TOXIC SUBSTANCES FROM COAL COMBUSTION

    SciTech Connect

    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 carried

  20. NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    SciTech Connect

    Jost O.L. Wendt

    2003-06-02

    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.

  1. FINE PARTICAL AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    SciTech Connect

    Jost O.L. Wendt; Wayne S. Seames; Art Fernandez

    2003-09-21

    This research project focuses on pollutants from the combustion of mixtures of dried municipal sewage sludge (MSS) and pulverized coal. The objective was to determine potential tradeoffs between CO{sub 2} mitigation through using a CO{sub 2} neutral fuel, such as municipal sewage sludge, and the emergence of other potential problems such as the emission of toxic fly ash particles. The work led to new insight into mechanisms governing the partitioning of major and trace metals from the combustion of sewage sludge, and mixtures of coal and sewage sludge. The research also showed that the co-combustion of coal and sewage sludge emitted fine particulate matter that might potentially cause greater lung injury than that from the combustion of either coal alone or municipal sewage sludge alone. The reason appeared to be that the toxicity measured required the presence of large amounts of both zinc and sulfur in particles that were inhaled. MSS provided the zinc while coal provided the sulfur. Additional research showed that the toxic effects could most likely be engineered out of the process, through the introduction of kaolinite sorbent downstream of the combustion zone, or removing the sulfur from the fuel. These results are consequences of applying ''Health Effects Engineering'' to this issue. Health Effects Engineering is a new discipline arising out of this work, and is derived from using a collaboration of combustion engineers and toxicologists to mitigate the potentially bad health effects from combustion of this biomass fuel.

  2. NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    SciTech Connect

    Jost O.L. Wendt

    2001-08-01

    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. To this end work is progress using an existing 17kW downflow laboratory combustor, available with coal and sludge feed capabilities. 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). The proposed work uses existing analytical and experimental facilities and draws on 20 years of research on NO{sub x} and fine particles that has been funded by DOE in this laboratory. Four barrels of dried sewage sludge are currently in the laboratory. Insofar as possible pertinent mechanisms will be elucidated. Tradeoffs between CO{sub 2} control, NO{sub x} control, and inorganic fine particle and toxic metal emissions will be determined. For the Third Quarter of this project we present our data on trace metal partitioning obtained from combustion of MSS and Gas, MSS and Coal and Coal and Gas alone.

  3. Fluidized bed coal combustion reactor

    NASA Technical Reports Server (NTRS)

    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. Fluidized bed coal combustion reactor

    SciTech Connect

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

    1981-09-01

    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. Official Gazette of the U.S. Patent and Trademark Office

  5. NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    SciTech Connect

    Jost O.L. Wendt

    2003-01-31

    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 CO{sub 2} control, NO{sub x} control, and inorganic fine particle and toxic metal emissions will be determined. Previous research results have demonstrated that the inhalation of coal/MSS ash particles cause an increase in lung permeability than coal ash particles alone. Elemental analysis of the coal/MSS ash particles showed that Zn was more abundant in these ash particles than the ash particles of coal ash alone.

  6. TOXIC SUBSTANCES FROM COAL COMBUSTION

    SciTech Connect

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

    1999-05-10

    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 Environ-mental 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 January 1999 to 31 March 1999. During this period, a full Program Review Meeting was held at the University of Arizona. At this meeting, the progress of each group was reviewed, plans for the following 9 month period were discussed, and action items (principally associated with the transfer of samples and reports among the various investigators) were identified.

  7. A systems approach to risk assessment: Application to methylmercury from coal combustion

    SciTech Connect

    Saroff, L.; Lipfert, F.W.; Moskowitz, P.D.

    1995-01-01

    The Department of Energy (DOE) asked Brookhaven National Laboratory (BNL) to perform a probabilistic assessment of the health risks associated with Hg from coal-fired power plants. The objective of the assessment is to estimate the incremental health risks that might ensue from a typical coal-fired power plant, together with their uncertainties, taking into account existing background levels and the actual adverse health effects that have previously been associated with exposure to various Hg species. Mercury has a long history of association with adverse neurological effects at high exposure levels. The most important current exposure pathway has been found to be ingestion of fish containing methylmercury (MeHg), which is the end product of bioconcentration moving up the aquatic food chain. Mercury can enter natural waters from either industrial discharges or from atmospheric deposition of various inorganic Ho. compounds. Because of the worldwide background and the existence of local emissions sources, Hg deposition must be considered on local, regional and global scales. The regulatory technical challenge presented by methy1mercury is to protect public health without foreclosing an appreciable a portion of the food supply or impacting on the lifestyles of North American native populations. This paper presents an abbreviated account of the DOE/BNL risk assessment, as viewed from a systems perspective. We review the structure of the model, the sources of data used, the assumptions that were made, and the interpretation of the findings. Since publication of the first risk assessment report, we have refined our estimates of local atmospheric dispersion and deposition and {open_quotes}calibrated{close_quotes} the pharmacokinetic portion of the model against observations.

  8. Assessing coal combustion and sourcing strategies using EPRI`s CQIM{sup {trademark}}

    SciTech Connect

    Stallard, G.S.; Jennison, K.D.

    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.

  9. NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    SciTech Connect

    Jost O.L. Wendt

    2001-01-31

    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. To this end we shall use an existing 17kW downflow laboratory combustor, available with coal and sludge feed capabilities. 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). The proposed work uses existing analytical and experimental facilities and draws on 20 years of research on NO{sub x} and fine particles that has been funded by DOE in this laboratory. Four barrels of dried sewage sludge are currently in the laboratory. Insofar as possible pertinent mechanisms will be elucidated. Tradeoffs between CO{sub 2} control, NO{sub x} control, and inorganic fine particle and toxic metal emissions will be determined. For the First Quarter of this three year project work has centered around recruiting a graduate student to take responsibility for execution of portions of the research, and modifying the furnace and supporting equipment to allow the combustion of coal/MMS mixtures. We have readied the analytical panel for measuring NO{sub x} and other gaseous pollutants. We expect initial experiments for data gathering for coal/MSS mixtures to commence in the next Quarter.

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

    SciTech Connect

    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.

  11. TECHNOLOGIES FOR CONTROLLING POLLUTANTS FROM COAL COMBUSTION

    EPA Science Inventory

    The paper is an overview of EPA's efforts in developing technology for controlling pollutants from coal combustion. SO2, NOx, and particles are the predominant pollutants emitted from the combustion of coal. One goal of current EPA research and development is to reduce the costs ...

  12. NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    SciTech Connect

    Jost O.L. Wendt

    2001-05-04

    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) NO{sub x} 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. To this end we shall use an existing 17kW downflow laboratory combustor, available with coal and sludge feed capabilities. 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 NO{sub x} and low NO{sub x} combustion conditions will be investigated (unstaged and staged combustion). The proposed work uses existing analytical and experimental facilities and draws on 20 years of research on NO{sub x} and fine particles that has been funded by DOE in this laboratory. Four barrels of dried sewage sludge are currently in the laboratory. Insofar as possible pertinent mechanisms will be elucidated. Tradeoffs between CO{sub 2} control, NO{sub x} control, and inorganic fine particle and toxic metal emissions will be determined.

  13. Electrochemical protection of coal from spontaneous combustion

    SciTech Connect

    Aleksandrov, I.V.; Burkov, P.A.; Kamneva, A.I.; Khokhlov, Yu.I.

    1984-01-01

    An electrochemical method is described for the protection of coal stocks from self-heating and spontaneous combustion. Cathodic polarisation is effected by an external source of direct current using contact electrodes situated in the coal. Practically complete suppression of self-heating is claimed for 450-500 m/sup 3/ volumes of coal at an insignificant energy cost.

  14. Toxic substances from coal combustion -- a comprehensive assessment. Quarterly technical progress report, 1 April 1996--30 June 1996

    SciTech Connect

    Bool, L.E. III; Senior, C.L.; Huggins, F.; Huffman, G.P.; Shah, N.

    1996-07-01

    Before electric utilities can plan or implement emissions minimization strategies for hazardous pollutants, they must have an accurate and site-specific means of predicting emissions in all effluent streams for the broad range of fuels and operating conditions commonly utilized. Development of a broadly applicable emissions model useful to utility planners first requires a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion (specifically in Phase I, As, Se, Cr, and possibly Hg). PSI Technologies (PSIT) and its team members will achieve this objective through the development of an {open_quotes}Engineering Model{close_quotes} that accurately predicts the formation and partitioning of toxic species as a result of coal combustion. The {open_quotes}Toxics Partitioning Engineering Model{close_quotes} (ToPEM) will be applicable to all conditions including new fuels or blends, low-NO{sub x} combustion systems, and new power systems being advanced by DOE in the Combustion 2000 program. This report describes the mineralogy and chemical analysis of bituminous coal samples.

  15. Leachability of trace elements in coal and coal combustion wastes

    SciTech Connect

    Rice, C.A.; Breit, G.N.; Fishman, N.S.; Bullock, J.H. Jr.

    1999-07-01

    Leaching of trace elements from coal and coal combustion waste (CCW) products from a coal-fired power plant, burning coal from the Appalachian and Illinois basins, was studied using deionized (DI) water as a lixiviant to resemble natural conditions in waste disposal sites exposed to dilute meteoric water infiltration. Samples of bottom ash, fly ash, and feed coal were collected from two combustion units at monthly intervals, along with a bulk sample of wastes deposited in an on-site disposal pond. The units burn different coals, one a high-sulfur coal (2.65 to 3.5 weight percent S) and the other, a low-sulfur coal (0.6--0.9 eight percent S). Short-term batch leaches with DI water were performed for times varying from a few minutes to 18 hours. Select fly ash samples were also placed in long-term (> 1 year) flow-through columns.

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

    SciTech Connect

    Hardesty, D.R.; 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.

  17. NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    SciTech Connect

    Jost O.L. Wendt

    2002-02-05

    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) NO{sub x} 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. To this end work is progress using an existing 17kW downflow laboratory combustor, available with coal and sludge feed capabilities. 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 NO{sub x} and low NO{sub x} combustion conditions will be investigated (unstaged and staged combustion). The proposed work uses existing analytical and experimental facilities and draws on 20 years of research on NO{sub x} and fine particles that has been funded by DOE in this laboratory. Four barrels of dried sewage sludge are currently in the laboratory. Insofar as possible pertinent mechanisms will be elucidated. Tradeoffs between CO{sub 2} control, NO{sub x} control, and inorganic fine particle and toxic metal emissions will be determined. For the Fifth Quarter of this project we focus on determining whether certain trace metals are associated with certain major species, such as calcium and iron. To this end we present data showing correlations between As, Se,and Sb and major species, such as Ca and Fe. Conversely, lack of correlation between trace metals and elements, such as aluminum can also be used to infer lack of chemical association.

  18. NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    SciTech Connect

    Jost O.L. Wendt

    2002-02-05

    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) NO{sub x} 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. To this end work is progress using an existing 17kW downflow laboratory combustor, available with coal and sludge feed capabilities. 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 NO{sub x} and low NO{sub x} combustion conditions will be investigated (unstaged and staged combustion). The proposed work uses existing analytical and experimental facilities and draws on 20 years of research on NO{sub x} and fine particles that has been funded by DOE in this laboratory. Four barrels of dried sewage sludge are currently in the laboratory. Insofar as possible pertinent mechanisms will be elucidated. Tradeoffs between CO{sub 2} control, NO{sub x} control, and inorganic fine particle and toxic metal emissions will be determined. Progress in the Sixth Quarter (January 1, 2002 through March 31, 2002) was slow because of slagging problems in the combustor. These required the combustor to be rebuilt, a job that is not yet complete. A paper describing our results heretofore has been accepted by the Journal Environmental Science and Technology.

  19. SPONTANEOUS COAL COMBUSTION; MECHANISMS AND PREDICTION.

    USGS Publications Warehouse

    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.

  20. Toxic substances from coal combustion -- A comprehensive assessment. Quarterly report number 2, January 1--March 31, 1996

    SciTech Connect

    Bool, L.E. III; Senior, C.L.; Huggins, F.; Huffman, G.P.; Shah, N.; Wendt, J.; Sarofim, A.F.; Zeng, T.

    1996-04-01

    The technical objectives of this project are: 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; to identify the mechanisms governing the post-vaporization interaction of toxic elements and major minerals or unburnt char; to determine the effect of combustion environment (i.e., fuel rich or fuel lean) on the partitioning of trace elements between vapor, submicron fume, and fly ash during the combustion of pulverized coal; to model the partitioning of toxic elements between various chemical species in the vapor phase and between the vapor phase and complex aluminosilicate melts; and to develop a frame work for incorporating the results of the program into the Engineering Model for Ash Formation (EMAF). A description of the work plan for accomplishing these objectives is presented in Section 2 of this report. In Section 3 of this report the authors define a detailed list of deliverables expected and consists of a group by group breakdown of the critical experiments to be performed, and a discussion of how that data fits into the overall program. In Section 4 the four coals selected for this program are reported. In Section 5 preliminary XAFs analysis by UKy personnel is discussed. Section 6 consists of a discussion of trace element analysis (INAA) of two size fractions of the Elkhorn-Hazard coal. A discussion of the modifications to the U.Arizona self-sustained combustor is presented in Section 7. Modifications included addition of a baghouse and improvements in the on-line safety and analytical systems. In Section 8 a detailed QA/QC protocol is presented.

  1. COSTS FOR ADVANCED COAL COMBUSTION TECHNOLOGIES

    EPA Science Inventory

    The report gives results of an evaluation of the development status of advanced coal combustion technologies and discusses the preparation of performance and economic models for their application to electric utility plants. he technologies addressed were atmospheric fluidized bed...

  2. Combustion of Coal/Oil/Water Slurries

    NASA Technical Reports Server (NTRS)

    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.

  3. Coal Combustion Products Extension Program

    SciTech Connect

    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 40% by 2010, the CCP Extension Program be

  4. Coal combustion: Nuclear resource or danger

    SciTech Connect

    Gabbard, A.

    1993-01-01

    Both the benefits and hazards of coal combustion are more far-reaching than are generally recognized. Technologies exist to remove, store, and generate energy from the radioactive isotopes released to the environment by coal combustion. When considering the nuclear consequences of coal combustion, policymakers should look at the data and recognize that the amount of uranium-235 alone dispersed by coal combustion is the equivalent of dozens of nuclear reactor fuel loadings. They should also recognize that the nuclear fuel potential of the fertile isotopes of thorium-232 and uranium-238, which can be converted in reactors to fissionable elements by breeding, yields a virtually unlimited source of nuclear energy that is frequently overlooked as a natural resource. In short, naturally occurring radioactive species released by coal combustion are accumulating in the environment along with minerals such as mercury, arsenic, silicon, calcium, chlorine, and lead, sodium, as well as metals such as aluminum, iron, lead, magnesium, titanium, boron, chromium, and others that are continually dispersed in millions of tons of coal combustion by-products. The potential benefits and threats of these released materials will someday be of such significance that they should not now be ignored.

  5. The coal slime slurry combustion technology

    SciTech Connect

    Li, Y.; Xu, Z.

    1997-12-31

    This paper presents the coal slime slurry combustion technology in circulating fluidized bed (CFB) boilers. The technique is that the slurry-based flow from the concentrator in the coal washery plant directly feeds into the fluidized bed by pump for combustion after a simple filtration and enrichment to an approximate concentration of 50% of coal. The coal slime slurry can burn in a CFB boiler alone or jointly with coal refuse. The technique has been used in a 35 t/h (6MWe) CFB for power generation. The result shows that the combustion efficiency is over 96% and boiler thermal efficiency is over 77%. As compared with burning coal refuse alone, the thermal efficiency was improved by 3--4 percent. This technology is simple, easy to operate and reliable. It is an effective way to utilize coal slime slurry. It has a practical significance for saving coal resources and reducing environmental pollution near coal mine areas. As a clean coal technology, it will result in great social, environmental and economic benefits.

  6. Coal slurry combustion and technology. Volume 2

    SciTech Connect

    Not Available

    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)

  7. TRACE METAL TRANSFORMATION MECHANISMS DURING COAL COMBUSTION

    EPA Science Inventory

    The article reviews mechanisms governing the fate of trace metals during coal combustion and presents new theoretical results that interpret existing data. Emphasis is on predicting the size-segregated speciation of trace metals in pulverized-coal-fired power plant effluents. Thi...

  8. TRACE METAL TRANSFORMATION MECHANISMS DURING COAL COMBUSTION

    EPA Science Inventory

    The article reviews mechanisms governing the fate of trace metals during coal combustion and presents new theoretical results that interpret existing data. mphasis is on predicting the size-segregated speciation of trace metals in pulverized-coal-fired power plant effluents. his ...

  9. Combustion of dense streams of coal particles

    SciTech Connect

    Annamalai, K.

    1992-04-14

    Research on coal combustion continued. Activities during November 29, 1991 to February 28, 1992 includes: Further analytical results on char array combustion and internal ignition of porous char; preliminary runs using a flat flame burner have been made and a blue flat flame has been obtained; a CID camera, EPIX frame grabber and software, Sony monitor and a 486 Computer to handle image processing frame by frame have been acquired; a new coal feeder has been constructed for feeding through the flat flame burner. Coal experiments have not yet been conducted. Coal samples from Penn State Coal Bank were also acquired for use in the experiments. They include bituminous and subbituminous coals of differing VM.

  10. Biomedically relevant chemical and physical properties of coal combustion products.

    PubMed Central

    Fisher, G L

    1983-01-01

    The evaluation of the potential public and occupational health hazards of developing and existing combustion processes requires a detailed understanding of the physical and chemical properties of effluents available for human and environmental exposures. These processes produce complex mixtures of gases and aerosols which may interact synergistically or antagonistically with biological systems. Because of the physicochemical complexity of the effluents, the biomedically relevant properties of these materials must be carefully assessed. Subsequent to release from combustion sources, environmental interactions further complicate assessment of the toxicity of combustion products. This report provides an overview of the biomedically relevant physical and chemical properties of coal fly ash. Coal fly ash is presented as a model complex mixture for health and safety evaluation of combustion processes. PMID:6337824

  11. Health impacts of domestic coal combustion

    SciTech Connect

    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 poisoning

  12. Assessment of Research Needs for Coal Utilization

    SciTech Connect

    Penner, S.S.

    1983-08-01

    The Coal Combustion and Applications Working Group (CCAWG), at the request of J.W. Mares (Assistant Secretary for Fossil Energy) and A.W. Trivelpiece (Director, Office of Energy Research), has reviewed and evaluated the U.S. programs on coal combustion and utilization. The important topical areas of coal gasification and coal liquefaction have been deliberately excluded because R and D needs for these technologies were reviewed previously by the DOE Fossil Energy Research Working Group. The CCAWG studies were performed in order to provide an independent assessment of research areas that affect prospects for augmented coal utilization. In this report, we summarize the findings and research recommendations of CCAWG.

  13. Mutagenicity and carcinogenicity of car exhausts and coal combustion emissions

    SciTech Connect

    Holmberg, B.; Ahlbourg, U.

    1983-01-01

    Car exhausts and coal combustion emissions may cause a spectrum of health effects, varying from annoyance reactions, to bronchitis, to cancer in the respiratory organs and possibly also other organs. Deaths in cardiovascular diseases in particularly sensitive individuals have furthermore, under certain circumstances, been associated with ambient air pollution. The objective of the meeting was to examine the relevance of short-term and long-term biological tests for mutagenicity and carcinogenicity to the assessment of human carcinogenic risk that may arise from exposure to air pollution from motor vehicle exhausts and coal combustion products. (135 refs.)

  14. Isotopic signature of atmospheric phosphate emitted from coal combustion

    NASA Astrophysics Data System (ADS)

    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 (<8 μg/g) with a wider and significantly lower δ18OP range of 10.6-16.5‰. The ash samples were found to have HCl-P δ18OP higher in ∼0-∼9‰ relative to the source coal. Similar isotopic values were found for ash with the same coal source country, regardless of the power station. Despite the low bioavailable P concentrations, fly ash could still be an important atmospheric P source to the 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.

  15. Coal combustion aerothermochemistry research. Final report

    SciTech Connect

    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.

  16. MONITORING STRATEGIES FOR FLUIDIZED BED COMBUSTION COAL PLANTS

    EPA Science Inventory

    Air and water monitoring strategies for commercial-size Fluidized Bed Combustion (FBC) coal plants are presented. This is one of five reports developing air and water monitoring strategies for advanced coal combustion (FBC), coal conversion (coal gasification and liquefaction), a...

  17. Enhanced Combustion Low NOx Pulverized Coal Burner

    SciTech Connect

    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 economic

  18. Electricity from Coal Combustion: Improving the hydrophobicity of oxidized coals

    NASA Astrophysics Data System (ADS)

    Seehra, Mohindar; Singh, Vivek

    2011-03-01

    To reduce pollution and improve efficiency, undesirable mineral impurities in coals are usually removed in coal preparation plants prior to combustion first by crushing and grinding coals followed by gravity separation using surfactant aided water flotation. However certain coals in the US are not amendable to this process because of their poor flotation characteristics resulting in a major loss of an energy resource. This problem has been linked to surface oxidation of mined coals which make these coals hydrophilic. In this project, we are investigating the surface and water flotation properties of the eight Argonne Premium (AP) coals using x-ray diffraction, IR spectroscopy and zeta potential measurements. The role of the surface functional groups, (phenolic -OH and carboxylic -COOH), produced as a result of chemisorptions of O2 on coals in determining their flotation behavior is being explored. The isoelectric point (IEP) in zeta potential measurements of good vs. poor floaters is being examined in order to improved the hydrophobicity of poor floating coals (e.g. Illinois #6). Results from XRD and IR will be presented along with recent findings from zeta potential measurements, and use of additives to improve hydrophobicity. Supported by USDOE/CAST, Contract #DE-FC26-05NT42457.

  19. Statistical kinetics for pulverized coal combustion

    SciTech Connect

    Hurt, R.H.; Lunden, M.M.; Brehob, E.G.; Maloney, D.J.

    1996-06-01

    Coal is a heterogeneous substance whose structure and properties are highly variable on the length scale of the particle sizes used in suspension-fired combustion systems. For certain applications the statistical variations among particles can play an important role. In this paper, three specialized, single-particle techniques are applied to quantify the variations in combustion reactivity and char particle density within pulverized char particle populations. Reactivity variations are investigated through captive particle imaging experiments and entrained flow reactor experiments employing single-particle optical diagnostics. Single-particle density variations are determined directly by a novel technique based on an electrodynamic microbalance equipped with an automated video imaging and image processing system. From these data, a coal-general statistical kinetic model is developed and validated against a large set of single-particle temperature measurements for ten coals of various rank burning in three different combustion environments. The model incorporates a single empirical parameter describing the heterogeneity in reactivity and can adequately describe the entire database using a single coal-independent value of this parameter. The use of the model is demonstrated in a series of numerical simulations of complete burnout process for size-classified and polydisperse fuel samples. The simulations show that incorporating statistical kinetics has an important effect on burnout predictions in certain cases, the importance increasing with decreases in temperature, mean reactivity, and breadth of the particle size distribution. 32 refs.

  20. Inhibition of spontaneous combustion of coal

    SciTech Connect

    Smith, A.C.; Miron, Y.; Lazzara, C.P.

    1988-01-01

    This report describes laboratory studies conducted to evaluate the effectiveness of 10 additives to inhibit the self-heating of coal. Aqueous additive solutions were applied to a bituminous coal with a high spontaneous combustion potential, and the minimum, self-heating temperatures (SHT's) of the dired coal-additive mixtures were determined in the Bureau's adiabatic heating oven. The relative effectiveness of the additives was determined by the observed changes in the minimum SHT's of the mixtures or by the time required for the sample temperature to reach 150{degrees}C, compared with the untreated coal and coal-water blank. Sodium nitrate, sodium chloride, and calcium carbonate were found to be the most effective inhibitors, followed by ammonium dihydrogen phosphate, calcium chloride ammonium chloride, sodium acetate, and potassium chloride. Two additives, sodium formate and sodium phosphate, promoted the self-heating process. Differential scanning calorimetry experiments on the coal-additive mixtures show that reactions occured between the coal and some of the additives, but these reactions did not infuluence the self-heating process.

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

    SciTech Connect

    Hardesty, D.R.; 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.

  2. EPRI's coal combustion product use research

    SciTech Connect

    Ladwig, K.

    2008-07-01

    For more than 20 years, EPRI's Coal Combustion Product Use Program has been a leader in providing research to demonstrate the value of using coal combustion products (CCPs) in construction and manufacturing. Work is concentrated on large-volume uses, increasing use in traditional applications, uses in light of changes in CCP quality resulting form increased and new air emissions controls for nitrogen oxides, sulfur oxides and mercury. Currently, EPRI is investigating opportunities for using higher volumes of Class C ash in concrete; approaches for ensuring that mercury controls do not adversely affect the use of CCPs; agricultural uses for products from flue gas desulfurization; possible markets for spray dryer absorber byproducts; and issues involved with the presence of ammonia in ash. Some recent results and future work is described in this article. 4 photos.

  3. Coal Combustion Products Extension Program

    SciTech Connect

    Tarunjit S. Butalia; William E. Wolfe

    2004-12-31

    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 space, (5

  4. COAL COMBUSTION PRODUCTS EXTENSION PROGRAM

    SciTech Connect

    Tarunjit S. Butalia; William E. Wolfe

    2005-05-15

    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 space, (5

  5. Coal Combustion Products Extension Program

    SciTech Connect

    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 space, (5

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

    SciTech Connect

    Hardesty, D.R.

    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.

  7. Combustion front propagation in underground coal gasification

    SciTech Connect

    Dobbs, R.L. II; Krantz, W.B.

    1990-10-01

    Reverse Combustion (RC) enhances coal seam permeability prior to Underground Coal Gasification. Understanding RC is necessary to improve its reliability and economics. A curved RC front propagation model is developed, then solved by high activation energy asymptotics. It explicitly incorporates extinction (stoichiometric and thermal) and tangential heat transport (THT) (convection and conduction). THT arises from variation in combustion front temperature caused by tangential variation in the oxidant gas flux to the channel surface. Front temperature depends only weakly on THT; front velocity is strongly affected, with heat loss slowing propagation. The front propagation speed displays a maximum with respect to gas flux. Combustion promoters speed front propagation; inhibitors slow front propagation. The propagation model is incorporated into 2-D simulations of RC channel evolution utilizing the boundary element method with cubic hermetian elements to solve the flow from gas injection wells through the coal to the convoluted, temporally evolving, channel surface, and through the channel to a gas production well. RC channel propagation is studied using 17 cm diameter subbituminous horizontally drilled coal cores. Sixteen experiments at pressures between 2000 and 3600 kPa, injected gas oxygen contents between 21% and 75%, and flows between 1 and 4 standard liters per minute are described. Similarity analysis led to scaling-down of large RC ({approx}1 m) to laboratory scale ({approx}5 cm). Propagation velocity shows a strong synergistic increase at high levels of oxygen, pressure, and gas flow. Char combustion is observed, leaving ash-filled, irregularly shaped channels. Cracks are observed to penetrate the char zone surrounding the channel cores. 69 refs., 54 figs., 4 tabs.

  8. Enhanced Combustion Low NOx Pulverized Coal Burner

    SciTech Connect

    Ray Chamberland; Aku Raino; David Towle

    2006-09-30

    For more than two decades, ALSTOM Power Inc. (ALSTOM) has developed a range of low cost, in-furnace technologies for NOx emissions control for the domestic U.S. pulverized coal fired boiler market. This includes ALSTOM's internally developed TFS 2000 firing system, and various enhancements to it developed in concert with the U.S. Department of Energy (DOE). As of 2004, more than 200 units representing approximately 75,000 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 coals to 0.10 lb/MMBtu for subbituminous coals, 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 (retrofit) boiler equipment. If enacted, proposed Clear Skies legislation will, by 2008, require an average, effective, domestic NOx emissions rate of 0.16 lb/MMBtu, which number will be reduced to 0.13 lb/MMBtu by 2018. Such levels represent a 60% and 67% reduction, respectively, from the effective 2000 level of 0.40 lb/MMBtu. 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. In light of these needs, ALSTOM, in cooperation with the DOE, is developing 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 at less than 3/4 the cost of an SCR with low to no impact on balance of plant issues when firing a high volatile bituminous coal. Such coals can be more economic to fire than subbituminous or Powder River Basin (PRB) coals, but are more problematic from a NOx control standpoint as existing

  9. Managing coal combustion residues in mines

    SciTech Connect

    2006-07-01

    Burning coal in electric utility plants produces, in addition to power, residues that contain constituents which may be harmful to the environment. The management of large volumes of coal combustion residues (CCRs) is a challenge for utilities, because they must either place the CCRs in landfills, surface impoundments, or mines, or find alternative uses for the material. This study focuses on the placement of CCRs in active and abandoned coal mines. The Committee on Mine Placement of Coal Combustion Wastes of the National Research Council believes that placement of CCRs in mines as part of the reclamation process may be a viable option for the disposal of this material as long as the placement is properly planned and carried out in a manner that avoids significant adverse environmental and health impacts. This report discusses a variety of steps that are involved in planning and managing the use of CCRs as minefills, including an integrated process of CCR characterization and site characterization, management and engineering design of placement activities, and design and implementation of monitoring to reduce the risk of contamination moving from the mine site to the ambient environment. Enforceable federal standards are needed for the disposal of CCRs in minefills to ensure that states have adequate, explicit authority and that they implement minimum safeguards. 267 refs., 6 apps.

  10. Catalytic combustion of coal-derived liquids

    NASA Technical Reports Server (NTRS)

    Bulzan, D. L.; Tacina, R. R.

    1981-01-01

    A noble metal catalytic reactor was tested with three grades of SRC 2 coal derived liquids, naphtha, middle distillate, and a blend of three parts middle distillate to one part heavy distillate. A petroleum derived number 2 diesel fuel was also tested to provide a direct comparison. The catalytic reactor was tested at inlet temperatures from 600 to 800 K, reference velocities from 10 to 20 m/s, lean fuel air ratios, and a pressure of 3 x 10 to the 5th power Pa. Compared to the diesel, the naphtha gave slightly better combustion efficiency, the middle distillate was almost identical, and the middle heavy blend was slightly poorer. The coal derived liquid fuels contained from 0.58 to 0.95 percent nitrogen by weight. Conversion of fuel nitrogen to NOx was approximately 75 percent for all three grades of the coal derived liquids.

  11. Transformations of inorganic coal constituents in combustion systems

    SciTech Connect

    Helble, J.J.; Srinivasachar, S.; Wilemski, G.; Boni, A.A. ); Kang, Shin-Gyoo; Sarofim, A.F.; Graham, K.A.; Beer, J.M. ); Peterson, T.W.; Wendt, J.O.L.; Gallagher, N.B.; Bool, L. ); 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.

  12. Combustion and fuel characterization of coal-water fuels

    SciTech Connect

    Lachowicz, Y.V.; LaFlesh, R.C.

    1987-07-01

    This five-year research project was established to provide sufficient data on coal-water fuel (CWF) chemical, physical, and combustion properties to assess the potential for commercial firing in furnaces designed for gas or oil firing. Extensive laboratory testing was performed at bench-scale, pilot-scale (4 {times} 10{sup 6}Btu/hr) and commercial-scale (25 {times} 10{sup 6} to 50 {times} 10{sup 6}Btu/hr) on a cross-section of CWFs. Fuel performance characteristics were assessed with respect to coal properties, level of coal beneficiation, and slurry formulation. The performance of four generic burner designs was also assessed. Boiler performance design models were applied to analyze the impacts associated with conversion of seven different generic unit designs to CWF firing. Equipment modifications, operating limitations, and retrofit costs were determined for each design when utilizing several CWFs. This report summarizes studies conducted under Task 4. The objective was to quantify CWF atomization and combustion properties utilizing industrial/utility scale equipment. Burners were evaluated and combustion performance differences identified for various CWF formulations. 12 refs., 23 figs., 6 tabs.

  13. DNA adducts as biomarkers for assessing exposure to polycyclic aromatic hydrocarbons in tissues from Xuan Wei women with high exposure to coal combustion emissions and high lung cancer mortality

    SciTech Connect

    Mumford, J.L.; Lee, X.; Lewtas, J.; Young, T.L.; Santella, R.M.

    1993-03-01

    The high lung cancer rate in Xuan Wei, China, is associated with smoky coal use in unvented homes. Smoky coal combustion emits higher levels of polycyclic aromatic hydrocarbons (PAH) than wood combustion. The study used DNA adducts as a biomarker for human exposure to PAH from combustion emissions. DNA adducts were determined by enzyme-linked immunosorbent assays (ELISA) in placentas and peripheral and cord white blood cells from Xuan Wei women burning smoky coal or wood and from Beijing women using natural gas. Color ELISA gave positive results in 58%, 47%, and 5% of the placentas from Xuan Wei women burning smoky coal without and with chimneys, and from Beijing women, respectively. Fluorescence ELISA indicated that 46%, 65%, 56%, and 25% of placentas were positive from Xuan Wei women without and with chimneys, Xuan Wei women burning wood, and Beijing controls, respectively. PAH-DNA adducts were detected in a higher percentage of placentas from Xuan Wei women exposed to smoky coal or wood emissions than those of the Beijing controls. The results suggest that DNA adducts can be used as a qualitative biomarker to assess human exposure to combustion emissions.

  14. Combustion and fuel characterization of coal-water fuels

    SciTech Connect

    Not Available

    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.

  15. Mercury emissions from coal combustion in China

    SciTech Connect

    David G. Streets; Jiming Hao; Shuxiao Wang; Ye Wu

    2009-07-01

    This chapter reviews the magnitude and spatial distribution of mercury emissions from coal combustion in China. Due to the large quantities of coal burned and the relatively low level of technology, particularly in industry, emissions are high. Emissions were stable at about 200-210 Mg during the period 1995-2000, but because of rapid economic growth starting in 2001, mercury emissions grew quickly to a value of 334 Mg in 2005. The annual average growth rate for the period 1995-2005 was 5.1%. The uncertainty in emission estimates is about {+-}35% (95% confidence intervals). Emissions are concentrated in those provinces with high concentrations of mercury in coal (like Guizhou Province) and provinces in which a lot of coal is burned (like Shanxi Province). Because significant amounts of coal are burned in homes and small industrial facilities, without any kind of emission control at all, emissions of particulate mercury are higher in China than in the developed world; the speciation profile nationwide is: 64% Hg{sup II}, 19% Hg{sup p}, and 17% Hg{sup 0}. In the future, growth in mercury emissions is expected to be limited by the application of FGD for SO{sub 2} control and other advanced technologies. Estimates of emissions are hampered by the lack of comprehensive and reliable emissions testing programs in China.

  16. Coal combustion products: trash or treasure?

    SciTech Connect

    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.

  17. WASTE AND WATER MANAGEMENT FOR CONVENTIONAL COAL COMBUSTION ASSESSMENT REPORT--1979. VOLUME IV. UTILIZATION OF FGC WASTES

    EPA Science Inventory

    The report, the fourth of five volumes, focuses on utilization of coal ash and FGD wastes. With increasing utilization of coal, generation of these wastes is expected to grow, but at a slower rate than generation, thus increasing the volume of wastes sent to disposal. Many uses f...

  18. MERCURY CAPTURE ON COAL COMBUSTION FLY ASH. (R827649)

    EPA Science Inventory

    A study was performed at the Energy and Environmental Research Center (EERC) to test the hypotheses that (1) different carbon types contained in coal combustion fly ash have variable sorption capabilities relative to mercury and (2) the inorganic fraction of coal combustion fl...

  19. [Retention of selenium volatility using lime in coal combustion].

    PubMed

    Zhang, J; Ren, D; Zhong, Q; Xu, F; Zhang, Y; Yin, J

    2001-05-01

    For understanding the volatility of selenium, the effect of the contents of exchangeable cations of coal on it, and the retention of selenium using CaO in coal combustion, the sequential chemistry extraction, the fixed bed and circulating fluidized bed (CFB) combustion, X-ray diffraction (XRD) and atomic fluorescence spectrometry (AFS) were undertaken. The results showed that the volatility of selenium was more than 97% in coal combustion at 815 degrees C, and the volatility of selenium was affected by the content of exchangeable cations of coal in low-middle temperature. It was identified that lime can restrain the volatility of selenium. In fixed bed combustion of coal, the retention rates of selenium volatility were between 11.6% and 50.7% using lime. In circulating fluidized bed combustion of coal, partitioning of selenium changed very much in ash of different size fraction between without lime and with lime. Comparing with combustion without lime, the content of selenium in ash from chimney was less than fourth times and that in leaching water from chimney decreased by two orders of magnitude using lime. Retention of selenium volatility using lime is so effective in coal combustion, especially in CFB combustion of coal. PMID:11507891

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

    SciTech Connect

    Hardesty, D.R.; 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.

  1. Ignition and combustion of coal particles

    SciTech Connect

    Gomez, C.O.; Vastola, F.J.

    1983-09-01

    A subbituminous coal was used in this study. Particles from the 850 to 1000 ..mu.. sieve fraction were injected into a reaction furnace swept with air at temperature levels of 928/sup 0/, 980/sup 0/, 1076/sup 0/, 1118/sup 0/ and 1273/sup 0/K. The experimental technique, based upon the simultaneous measurement of the carbon monoxide, carbon dioxide, and the intensity of the light generated during the combustion, provides quantitative information about the ignition and the subsequent burn-off of the residual particle. Homogeneous ignition is detected at temperatures of 1076/sup 0/K and higher. The apparatus designed provides the special characteristics required in this study, and the transition between the ignition mechanisms is achieved within the range of operation conditions for this particular coal. The ignition mechanism is determined not only from the measurement of light intensity during the combustion, but also from the gas evolution curves. The results show the convenience of using these complementary techniques for the measurement of the ignition mechanism. 4 figures, 2 tables.

  2. Combustion behavior of low rank coal water slurries

    SciTech Connect

    Yavuz, R.; Kuecuekbayrak, S.; Williams, A.

    1996-12-31

    Coal water slurries have been developed over the last 15 years as an alternative to fuel oil mainly in industry and power station boilers. Observing of droplet lifetime reveals details of the mechanism of the slurry combustion. In the present investigation, single droplet combustion of lignite water slurries using different Turkish lignites were experimentally studied by using single droplet combustion technique. The technique is based on thermometric method. Results of combustion behavior of low rank coal water slurries were compared with that of high rank coal water slurries which were found in the literature.

  3. On the combustion of bituminous coal chars

    SciTech Connect

    Sahu, R.

    1988-01-01

    The chars were made by pyrolyzing size-graded PSOC 1451 coal particles in nitrogen at 1000-1600K. Sized char particles were then used in subsequent experiments. Low temperature reactivities of such cenospheric chars were measured at 800K in a TGA. The effects of initial coal size, char size, pyrolysis temperature, and oxygen concentration were investigated. Single particle combustion experiments were done in both air and 50 percent oxygen ambients at 1000-1500K wall temperatures in a drop-tube laminar-flow reactor. The ignition transients of single burning particles were explained using a simple thermal model. Char samples were also partially oxidized at 1200-1500K and then physically characterized using optical and electron microscopy, gas adsorption methods, and mercury porosimetry. Results of characterization were compared to those done at 800K. Single particle combustion was numerically modeled. At first, a continuum model for asymptotic shrinking-core combustion was developed using apparent reaction rate and temperature-dependent properties. Later, a more general continuum model was developed that treated the internal morphology of the particles more realistically, as inferred from experiments. The steady-state diffusion equation was solved inside the particle to determine its theoretical temperature-time history. Good agreement with experimental results was found. The model was extended to include the effect of nonlinear kinetics. A discrete model for a cenospheric char particle was also developed, in which spherical voids were randomly placed in a spherical particle. Connectivity of the internal pore structure was accounted for.

  4. 75 FR 64974 - Notice of Data Availability on Coal Combustion Residual Surface Impoundments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-21

    ... data posted in the docket for EPA's proposed rulemaking (75 FR 51434, August 20, 2010) on the Disposal... Coal Combustion Residual Surface Impoundments AGENCY: Environmental Protection Agency (EPA). ACTION... combustion residual surface impoundments as well as reports and materials related to the site assessments...

  5. ENVIRONMENTAL EFFECTS OF WESTERN COAL COMBUSTION. PART III. THE WATER QUALITY OF ROSEBUD CREEK, MONTANA

    EPA Science Inventory

    The results of a study on Rosebud Creek, Montana, designed to assess the impacts on water quality of surface coal mining and/or coal combustion at Colstrip are summarized herein. A general degradation of water quality has been observed along the stream course but direct impacts o...

  6. DNA adducts as biomarkers for assessing exposure to polycyclic aromatic hydrocarbons in tissues from Xuan Wei women with high exposure to coal combustion emissions and high lung cancer mortality.

    PubMed Central

    Mumford, J L; Lee, X; Lewtas, J; Young, T L; Santella, R M

    1993-01-01

    The high lung cancer rate in Xuan Wei, China, is associated with smoky coal use in unvented homes, but not with wood or smokeless coal use. Smoky coal combustion emits higher polycyclic aromatic hydrocarbon (PAH) concentrations than wood combustion. This study used DNA adducts as biomarkers for human exposure to PAH from combustion emissions. DNA adducts were determined by enzyme-linked immunosorbent assays (ELISA) in placentas and peripheral and cord white blood cells (WBC) from Xuan Wei women burning smoky coal or wood and from Beijing women using natural gas. Color ELISA gave positive results in 58, 47, and 5% of the placentas from Xuan Wei women burning smoky coal without and with chimneys, and from Beijing women, respectively. Fluorescence ELISA indicated that 46, 65, 56, and 25% of placentas were positive from Xuan Wei women who lived in houses without and with chimneys, Xuan Wei women burning wood, and Beijing controls, respectively. Peripheral WBC samples were positive in 7/9, 8/9, and 3/9 for the Xuan Wei women who lived in houses without and with chimneys and Beijing women, respectively. PAH-DNA adducts were detected in a higher percentage of placentas from Xuan Wei women living in houses exposed to smoky coal or wood emissions than from those of the Beijing controls. No dose-response relationship was observed between the air benzo[alpha]pyrene concentrations and DNA adduct levels or percentage of detectable samples. The results suggest that DNA adducts can be used as a qualitative biomarker to assess human exposure to combustion emissions. PMID:8319664

  7. DEVELOPMENT OF A VORTEX CONTAINMENT COMBUSTOR FOR COAL COMBUSTION SYSTEMS

    EPA Science Inventory

    The report describes the development of a vortex containment combustor (VCC) for coal combustion systems, designed to solve major problems facing the conversion of oil- and gas-fired boilers to coal (e.g., derating, inorganic impurities in coal, and excessive formation of NOx and...

  8. DEVELOPMENT OF A VORTEX CONTAINMENT COMBUSTOR FOR COAL COMBUSTION SYTEMS

    EPA Science Inventory

    The report describes the development of a vortex containment combustor (VCC) for coal combustion systems, designed to solve major problems facing the conversion of oil- and gas-fired boilers to coal (e.g., derating, inorganic impurities in coal, and excessive formation of NOx and...

  9. Combustion and fuel characterization of coal-water fuels

    SciTech Connect

    Chow, O.K.; Gralton, G.W.; Lachowicz, Y.V.; Laflesh, R.C.; Levasseur, A.A.; Liljedahl, G.N.

    1989-02-01

    This five-year research project was established to provide sufficient data on coal-water fuel (CWF) chemical, physical, and combustion properties to assess the potential for commercial firing in furnaces designed for gas or oil firing. Extensive laboratory testing was performed at bench-scale, pilot-scale (4 {times} 10{sup 6}Btu/hr) and commercial-scale (25 {times} 10{sup 6} to 50 {times} 10{sup 6}Btu/hr) on a cross-section of CWFs. Fuel performance characteristics were assessed with respect to coal properties, level of coal beneficiation, and slurry formulation. The performance of four generic burner designs was also assessed. Boiler performance design models were applied to analyze the impacts associated with conversion of seven different generic unit designs to CWF firing. Equipment modifications, operating limitations, and retrofit costs were determined for each design when utilizing several CWFs. Unit performance analyses showed significantly better load capacity for utility and industrial boilers as the CWF feed coal ash content is reduced to 5% or 2.6%. In general, utility units had more attractive capacity limits and retrofit costs than the industrial boilers and process heaters studied. Economic analyses indicated that conversion to CWF firing generally becomes feasible when differential fuel costs are above $1.00/10{sup 6}Btu. 60 figs., 24 tabs.

  10. Toxic Substances from Coal Combustion - Forms of Occurrence Analyses

    SciTech Connect

    Allan Kolker; Curtis A. Palmer; Harvey E. Belkin; Jason Willet; Kathleen C. Kolb; Robert B. Finkelman; Sharon S. Crowley; Stanley J. Mroczkowski

    1998-12-14

    In a cooperative agreement with DOE (Contract No. DE- AC22- 95101), the USGS has participated with Physical Sciences, Inc. (PSI) in a project entitled "Toxic Substances From Coal Combustion -A Comprehensive Assessment". Samples from the Pittsburgh, Elkhorn/ Hazard, Illinois No. 6, and Wyodak program coals were examined to determine the mode of occurrence of selected trace elements (As, Se, Cr, Hg, and Ni) using selective leaching, scanning electron microscopy, electron microprobe analysis, and X- ray diffraction techniques. Among other findings, our results indicate that the bulk of the arsenic in the Pittsburgh and Illinois No. 6 coals is in pyrite. High percentages (60- 80%) of arsenic were leached by nitric acid, and microprobe data confirm the presence of arsenic in pyrite in each of these coals (concentrations ranging from <0.01 to 0.09 wt.% of the pyrite grains). In the Elkhorn/ Hazard coal, arsenic may have several modes of occurrences. About 30 percent of the arsenic in the Elkhorn/ Hazard coal was leached by hydrochloric acid, possibly indicating the presence of arsenates that were formed by the oxidation of pyrite. About 25 percent of the arsenic in the Elkhorn/ Hazard coal was leached by nitric acid, suggesting an association with pyrite. Only sixty percent of the total arsenic in the Elkhorn/ Hazard coal was leached. The low percentage of leachable arsenic may be accounted for by unleached pyrite grains, which were detected in solid residues from the nitric acid leach. In the Wyodak coal, arsenic probably occurs in iron oxides or carbonates (35 % arsenic leached by HCl) and clays (15% arsenic leached by HF). Arsenic in the Wyodak coal may also have an organic association, as indicated by low totals for leaching (50% unleached arsenic). In the four program coals 20 to 45 percent of the chromium was leached by hydrofluoric acid, suggesting an association with silicates (probably illite). Microprobe analysis of the Pittsburgh, Elkhorn/ Hazard, and Illinois

  11. [Coal fineness effect on primary particulate matter features during pulverized coal combustion].

    PubMed

    Lü, Jian-yi; Li, Ding-kai

    2007-09-01

    Three kinds of coal differed from fineness were burned in a laboratory-scale drop tube furnace for combustion test, and an 8-stage Andersen particle impactor was employed for sampling the primary particulate matter (PM), in order to study coal fineness effect on primary PM features during pulverized coal combustion. It has been shown that the finer the coal was, the finer the PM produced. PM, emission amount augmented with coal fineness decreased, and the amount of PM10 increased from 13 mg/g to 21 mg/g respectively generated by coarse coal and fine coal. The amount of PM2.5 increased from 2 mg/g to 8 mg/g at the same condition. Constituents and content in bulk ash varied little after three different fineness coal combustion, while the appearance of grading PM differed visibly. The value of R(EE) increased while the coal fineness deceased. The volatility of trace elements which were investigated was Pb > Cr > Zn > Cu > Ni in turn. The concentration of poisonous trace elements was higher which generated from fine coal combustion. The volatilization capacity was influenced little by coal fineness, but the volatilization extent was influenced differently by coal fineness. Fine coal combustion affects worse environment than coarse coal does. PMID:17990536

  12. Plane flame furnace combustion tests on JPL desulfurized coal

    NASA Technical Reports Server (NTRS)

    Reuther, J. J.; Kim, H. T.; Lima, J. G. H.

    1982-01-01

    The combustion characteristics of three raw bituminous (PSOC-282 and 276) and subbituminous (PSOC-230) coals, the raw coals partially desulfurized (ca -60%) by JPL chlorinolysis, and the chlorinated coals more completely desulfurized (ca -75%) by JPL hydrodesulfurization were determined. The extent to which the combustion characteristics of the untreated coals were altered upon JPL sulfur removal was examined. Combustion conditions typical of utility boilers were simulated in the plane flame furnace. Upon decreasing the parent coal voltaile matter generically by 80% and the sulfur by 75% via the JPL desulfurization process, ignition time was delayed 70 fold, burning velocity was retarded 1.5 fold, and burnout time was prolonged 1.4 fold. Total flame residence time increased 2.3 fold. The JPL desulfurization process appears to show significant promise for producing technologically combustible and clean burning (low SO3) fuels.

  13. Thermally induced structural changes in coal combustion

    SciTech Connect

    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.

  14. Toxic substances from coal combustion--forms of occurrence analyses

    SciTech Connect

    Crowley, S.S.; Palmer, C.A.; Kolker, A.; Finkelman, R.B.; Kolb, K.C.; Belkin, H.E.; Willet, J.C.

    1997-04-01

    The objective of this project was to provide analytical support for the Physical Sciences, Inc. (PSI) projects being performed under DOE Contract No. DE-AC22-95101 entitled `Toxic Substances from Coal Combustion - A Comprehensive Assessment`. The Pittsburgh, Elkhorn/Hazard, and Illinois No. 6 program coals were examined to determine the mode of occurrence of selected trace elements (As, Se, Cr, Hg, and Ni) using selective leaching, scanning electron microscopy, electron microprobe analysis, and X-ray diffraction techniques. Preliminary work was also completed for the Wyodak coal. Among other findings, our results indicate that the bulk of the arsenic in the Pittsburgh and Illinois No. 6 coals is in pyrite. High percentages (60-80%) of arsenic were leached by nitric acid, and microprobe data confirm the presence of arsenic in pyrite in each of these coals (concentrations ranging from <0.01 to 0.09 wt.% of the pyrite grains). In the Elkhorn/Hazard coal, arsenic may have several modes of occurrences. About 30 percent of the arsenic in the Elkhorn/Hazard coal was leached by hydrochloric acid, possibly indicating the presence of arsenates that were formed by the oxidation of pyrite. About 25 percent of the arsenic in the Elkhorn/Hazard coal was leached by nitric acid, suggesting an association with pyrite. Only sixty percent of the total arsenic in the Elkhorn/Hazard coal was leached. The low percentage of leachable arsenic may be accounted for by unleached pyrite grains, which were detected in solid residues from the nitric acid leach. In the Pittsburgh, Elkhorn/Hazard, and Illinois No. 6 coals, 20 to 25 percent of the chromium was leached by hydrofluoric acid, indicating some association with silicates (possibly illite). Microprobe analysis of these coals confirmed the presence of chromium in illite and possibly in other clays, at concentrations that were near the detection limits. Results related to the forms of occurrences of the other trace elements (Se, Hg, and Ni

  15. Enhancement of pulverized coal combustion by plasma technology

    SciTech Connect

    Gorokhovski, M.A.; Jankoski, Z.; Lockwood, F.C.; Karpenko, E.I.; Messerle, V.E.; Ustimenko, A.B.

    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.

  16. MECHANISMS AND OPTIMIZATION OF COAL COMBUSTION

    SciTech Connect

    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.

  17. HIGH PRESSURE COAL COMBUSTION KINETICS PROJECT

    SciTech Connect

    Chris Guenther; Bill Rogers

    2001-09-15

    The HPCCK project was initiated with a kickoff meeting held on June 12, 2001 in Morgantown, WV, which was attended by all project participants. SRI's existing g-RCFR reactor was reconfigured to a SRT-RCFR geometry (Task 1.1). This new design is suitable for performing the NBFZ experiments of Task 1.2. It was decided that the SRT-RCFR apparatus could be modified and used for the HPBO experiments. The purchase, assembly, and testing of required instrumentation and hardware is nearly complete (Task 1.1 and 1.2). Initial samples of PBR coal have been shipped from FWC to SRI (Task 1.1). The ECT device for coal flow measurements used at FWC will not be used in the SRI apparatus and a screw type feeder has been suggested instead (Task 5.1). NEA has completed a upgrade of an existing Fluent simulator for SRI's RCFR to a version that is suitable for interpreting results from tests in the NBFZ configuration (Task 1.3) this upgrade includes finite-rate submodels for devolatilization, secondary volatiles pyrolysis, volatiles combustion, and char oxidation. Plans for an enhanced version of CBK have been discussed and development of this enhanced version has begun (Task 2.5). A developmental framework for implementing pressure and oxygen effects on ash formation in an ash formation model (Task 3.3) has begun.

  18. Coal combustion: Science and technology of industrial and utility applications

    SciTech Connect

    Feng, J.

    1988-01-01

    Despite the competition of oil and gas and the increasing importance of nuclear power, coal is still one of the main sources of energy in the world. In some regions of the world, the reserve of oil and natural gas is nearly depleted. The supply of such fuels relies on shipment from foreign countries, and may be vulnerable to political crisis, while coals are still abundant and easily available. Therefore, the technology of burning coal for energy, which seems rather old, has not lost its vitality and is in fact developing fast. Because of industry development, especially in developing countries, more and more coal is burned each year. If coal is not burned properly, it may pollute the environment and affect the ecological balance of the surrounding regions. Great attention has been paid to curb these issues, and significant progress has been achieved. Technology of desulfurization of flue gases, low nitrogen oxide coal burners, and also the technology of clean burning of coal by fluidized-bed combustion have all been developed and commercialized. Further improvements are under development. At the same time, new techniques have been used in the measurements and diagnoses of coal combustion. These new techniques facilitate more efficient and cleaner burning of coal. Although coal combustion is a very complicated physiochemical phenomenon, the use of the computer enables and pushes forward the theoretical analysis of coal combustion. Besides, the mathematical modelling of the coal combustion process is also a fast progressing field of research and encouraging results have been obtained by scientists throughout the world. This book compiles the papers presented in the conference on the subject of clean cool technology and fluidized-bed combustion.

  19. Influence of combustion conditions and coal properties on physical properties of fly ash generated from pulverized coal combustion

    SciTech Connect

    Hiromi Shirai; Hirofumi Tsuji; Michitaka Ikeda; Toshinobu Kotsuji

    2009-07-15

    To develop combustion technology for upgrading the quality of fly ash, the influences of the coal properties, such as the size of pulverized coal particles and the two-stage combustion ratio during the combustion, on the fly ash properties were investigated using our test furnace. The particle size, density, specific surface area (obtained by the Blaine method), and shape of fly ash particles of seven types of coal were measured. It was confirmed that the size of pulverized coal particles affects the size of the ash particles. Regarding the coal properties, the fuel ratio affected the ash particle size distribution. The density and shape of the ash particles strongly depended on their ash size. Our results indicated that the shape of the ash particles and the concentration of unburned carbon affected the specific surface area. The influence of the two-stage combustion ratio was limited. 8 refs., 13 figs., 3 tabs.

  20. Plasma-supported coal combustion in boiler furnace

    SciTech Connect

    Askarova, A.S.; Karpenko, E.I.; Lavrishcheva, Y.I.; Messerle, V.E.; Ustimenko, A.B.

    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.

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

    USGS Publications Warehouse

    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. Combustion characterization of beneficiated coal-based fuels

    SciTech Connect

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

    1990-11-01

    The Pittsburgh Energy Technology Center of the US Department of Energy has contracted with Combustion Engineering, Inc. (CE) to perform a three-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 being run at the cleaning facility in Homer City, Pennsylvania, 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 (CVVT) or a dry microfine pulverized coal (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. Subcontractors to CE to perform parts of the test work are the Massachusetts Institute of Technology (MIT), Physical Science, Inc. Technology Company (PSIT) and the University of North Dakota Energy and Environmental Research Center (UNDEERC). Twenty fuels will be characterized during the three-year base program: three feed coals, fifteen BCFS, and two conventionally cleaned coals for full-scale tests. Approximately, nine BCFs will be in dry microfine coal (DMPC) form, and six BCFs will be in coal-water fuel (CWF) form. Additional BCFs would be characterized during optional project supplements.

  3. Hardened, environmentally disposable composite granules of coal cleaning refuse, coal combustion waste, and other wastes, and method preparing the same

    DOEpatents

    Burnet, George; Gokhale, Ashok J.

    1990-07-10

    A hardened, environmentally inert and disposable composite granule of coal cleaning refuse and coal combustion waste, and method for producing the same, wherein the coal combustion waste is first granulated. The coal cleaning refuse is pulverized into fine particles and is then bound, as an outer layer, to the granulated coal combustion waste granules. This combination is then combusted and sintered. After cooling, the combination results in hardened, environmentally inert and disposable composite granules having cores of coal combustion waste, and outer shells of coal cleaning refuse. The composite particles are durable and extremely resistant to environmental and chemical forces.

  4. Hardened, environmentally disposable composite granules of coal cleaning refuse, coal combustion waste, and other wastes, and method preparing the same

    SciTech Connect

    Burnet, G.; Gokhale, A.J.

    1990-07-10

    A hardened, environmentally inert and disposable composite granule of coal cleaning refuse and coal combustion waste and method for producing the same are disclosed, wherein the coal combustion waste is first granulated. The coal cleaning refuse is pulverized into fine particles and is then bound, as an outer layer, to the granulated coal combustion waste granules. This combination is then combusted and sintered. After cooling, the combination results in hardened, environmentally inert and disposable composite granules having cores of coal combustion waste, and outer shells of coal cleaning refuse. The composite particles are durable and extremely resistant to environmental and chemical forces. 3 figs.

  5. Combustion characterization of beneficiated coal-based fuels

    SciTech Connect

    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.

  6. Analysis of cyclic combustion of the coal-water suspension

    NASA Astrophysics Data System (ADS)

    Kijo-Kleczkowska, Agnieszka

    2011-04-01

    Combustion technology of the coal-water suspension creates a number of new possibilities to organize the combustion process fulfilling contemporary requirements, e.g. in the environment protection. Therefore the in-depth analysis is necessary to examine the technical application of coal as a fuel in the form of suspension. The research undertakes the complex investigations of the continuous coal-water suspension as well as cyclic combustion. The cyclic nature of fuel combustion results from the movement of the loose material in the flow contour of the circulating fluidized bed (CFB): combustion chamber, cyclone and downcomer. The experimental results proved that the cyclic change of oxygen concentration around fuel, led to the vital change of both combustion mechanisms and combustion kinetics. The mathematical model of the process of fuel combustion has been presented. Its original concept is based on the allowance for cyclic changes of concentrations of oxygen around the fuel. It enables the prognosis for change of the surface and the centre temperatures as well as mass loss of the fuel during combustion in air, in the fluidized bed and during the cyclic combustion.

  7. Fiber optic sensing system for temperature and gas monitoring in coal waste pile combustion environments

    NASA Astrophysics Data System (ADS)

    Viveiros, D.; Ribeiro, J.; Ferreira, J.; Lopez-Albada, A.; Pinto, A. M. R.; Perez-Herrera, R. A.; Diaz, S.; Lopez-Gil, A.; Dominguez-Lopez, A.; Esteban, O.; Martin-Lopez, S.; Auguste, J.-L.; Jamier, R.; Rougier, S.; Silva, S. O.; Frazão, O.; Santos, J. L.; Flores, D.; Roy, P.; Gonzalez-Herraez, M.; Lopez-Amo, M.; Baptista, J. M.

    2015-09-01

    It is presented an optical fiber sensing system projected to operate in the demanding conditions associated with coal waste piles in combustion. Distributed temperature measurement and spot gas sensing are requirements for such a system. A field prototype has been installed and is continuously gathering data, which will input a geological model of the coal waste piles in combustion aiming to understand their dynamics and evolution. Results are presented on distributed temperature and ammonia measurement, being noticed any significant methane emission in the short time period considered. Carbon dioxide is also a targeted gas for measurement, with validated results available soon. The assessment of this technology as an effective and reliable tool to address the problem of monitoring coal waste piles in combustion opens the possibility of its widespread application in view of the worldwide presence of coal related fires.

  8. AIR EMISSIONS FROM COMBUSTION OF SOLVENT REFINED COAL

    EPA Science Inventory

    The report gives details of a Solvent Refined Coal (SRC) combustion test at Georgia Power Company's Plant Mitchell, March, May, and June 1977. Flue gas samples were collected for modified EPA Level 1 analysis; analytical results are reported. Air emissions from the combustion of ...

  9. ANALYSIS FOR RADIONUCLIDES IN SRC AND COAL COMBUSTION SAMPLES

    EPA Science Inventory

    The report deals with the determination of the levels of uranium, thorium, and their daughter products in coal, SRC, coal flyash, and SRC flyash samples taken from Georgia Power Company's Plant Mitchell during the May and June 1977 combustion tests to compare the environmental em...

  10. Assessment of pulverized-coal-fired combustor performance. Parametric screening studies for the calculation of heat transfer in combustion chambers. Topical report

    SciTech Connect

    Richter, W.

    1982-01-01

    The screening studies performed to identify those parameters most influencing the thermal performance of full-scale combustion chambers, such as those of industrial furnaces or utility boilers are presented. Special attention is given to pulverized-coal (p.f.) firing. The report consists basically of two parts. Part one deals with overall thermal behavior, expressed in terms of a furnace efficiency and a furnace exit temperature. In part two, local heat transfer, characterized by local temperature and heat flux distributions, is investigated. It is also shown how these local inhomogeneities may influence the overall performance. The screening studies are carried out analytically.

  11. Remediation of abandoned mines using coal combustion by-products

    SciTech Connect

    Bulusu, S.; Aydilek, A.H.; Petzrick, P.; Guynn, R.

    2005-08-01

    Acid mine drainage (AMD) is a phenomenon that occurs when pyrite that is present in abandoned coal mines comes in contact with oxygen and water, which results in the formation of sulfuric acid and iron hydroxide. Grouting of an abandoned mine with alkaline materials provides a permanent reduction in acid production. This study investigates the success of coal combustion by-product (CCB)-based grout mixtures in reducing AMD. The laboratory phase included testing of grouts with different proportions of Class F fly ash, flue gas desulfurization by-product, fluidized bed combustion by-product, and quicklime, for slump, modified flow, bleed, and strength. Then the selected optimal grout mixture was injected into the Frazee mine, located in Western Maryland. Pre- and post-injection water quality data were collected to assess the long-term success of the grouting operation by analyzing mine water, surface water, and groundwater. Overall, the results indicated that CCB-based grouts can control the acid mine drainage. However, the mechanical properties of the grout are highly critical for the construction phase, and long-term monitoring is essential for evaluating the effectiveness of the grouting process.

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

    SciTech Connect

    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.

  13. REDUCTION OF NOx EMISSION FROM COAL COMBUSTION THROUGH OXYGEN ENRICHMENT

    SciTech Connect

    Western Research Institute

    2006-07-01

    BOC Process Gas Solutions and Western Research Institute (WRI) conducted a pilot-scale test program to evaluate the impact of oxygen enrichment on the emissions characteristics of pulverized coal. The combustion test facility (CTF) at WRI was used to assess the viability of the technique and determine the quantities of oxygen required for NOx reduction from coal fired boiler. In addition to the experimental work, a series of Computational Fluid Dynamics (CFD) simulations were made of the CTF under comparable conditions. A series of oxygen enrichment test was performed using the CTF. In these tests, oxygen was injected into one of the following streams: (1) the primary air (PA), (2) the secondary air (SA), and (3) the combined primary and secondary air. Emission data were collected from all tests, and compared with the corresponding data from the baseline cases. A key test parameter was the burner stoichiometry ratio. A series of CFD simulation models were devised to mimic the initial experiments in which secondary air was enriched with oxygen. The results from these models were compared against the experimental data. Experimental evidence indicated that oxygen enrichment does appear to be able to reduce NOx levels from coal combustion, especially when operated at low over fire air (OFA) levels. The reductions observed however are significantly smaller than that reported by others (7-8% vs. 25-50%), questioning the economic viability of the technique. This technique may find favor with fuels that are difficult to burn or stabilize at high OFA and produce excessive LOI. While CFD simulation appears to predict NO amounts in the correct order of magnitude and the correct trend with staging, it is sensitive to thermal conditions and an accurate thermal prediction is essential. Furthermore, without development, Fluent's fuel-NO model cannot account for a solution sensitive fuel-N distribution between volatiles and char and thus cannot predict the trends seen in the

  14. SPONCOM - a computer program for the prediction of the spontaneous combustion potential of an underground coal mine

    SciTech Connect

    Smith, A.C.; Rumancik, W.P.; Lazzara, C.P.

    1996-12-31

    The United States Bureau of Mines (USBM) developed SPONCOM to aid in the assessment of the spontaneous combustion risk of an underground mining operation. A prior knowledge of the spontaneous combustion risk of the coal and factors that increase that risk can be useful in the planning and development of proactive monitoring, ventilation, and prevention plans for the mining operation. Interactive data input screens prompt the user for information about the coal`s chemical and physical properties, the geologic and mining conditions encountered in the mining of the coal, and the mining practices employed. During the input process, {open_quote}expand{close_quote} screens provide the user with specific information on each input parameter. This information includes a description of the parameter and its effect on the overall spontaneous combustion risk. The program logic determines the coal`s relative spontaneous combustion potential, based on the coal`s proximate and ultimate analyses, and heating value. The program then evaluates the impact of the coal properties, geologic and mining conditions, and mining practices on the spontaneous combustion risk of the mining operation. The program output provides details on each factor that increases the risk of spontaneous combustion.

  15. Combustion of black coal in the form of coal-water slurry in low-capacity boilers

    NASA Astrophysics Data System (ADS)

    Maltsev, L. I.; Kravchenko, I. V.; Lazarev, S. I.; Lapin, D. A.

    2014-07-01

    The present paper describes the examples of experimental and industrial implementation of technologies of flame-droplet combustion of the coal-water mixture in furnaces above a bed consisting of burning coal and in a swirling-type furnace chamber. For preparing coal-water fuel (CWF), Kuznetsk coals of G and D ranks, as well as tailings of coking coals, were used. The future prospect of both technologies of coal combustion has been shown from both economic and environmental standpoints.

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

    USGS Publications Warehouse

    Hatch, Joseph R.; Bullock, John H., Jr.; 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).

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

    USGS Publications Warehouse

    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.

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

    SciTech Connect

    Baxter, L.L.

    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.

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

    SciTech Connect

    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.

  20. Effect of organic calcium compounds on combustion characteristics of rice husk, sewage sludge, and bituminous coal: thermogravimetric investigation.

    PubMed

    Zhang, Lihui; Duan, Feng; Huang, Yaji

    2015-04-01

    Experiments were conducted in a thermogravimetric analyzer to assess the enhancement of combustion characteristics of different solid fuels blended with organic calcium compounds (OCCs). Rice husk, sewage sludge, and bituminous coal, and two OCC were used in this study. Effect of different mole ratios of calcium to sulfur (Ca/S ratio) on the combustion characteristics were also investigated. Results indicated that combustion performance indexes for bituminous coal impregnated by OCC were improved, however, an inverse trend was found for sewage sludge because sewage sludge has lower ignition temperature and higher volatile matter content compared to those of OCC. For rice husk, effect of added OCC on the combustion characteristics is not obvious. Different solid fuels show different combustion characteristics with increases of Ca/S ratio. The maximum combustion performance indexes appear at Ca/S ratios of 1:1, 2:1, and 3:1 for OCC blended with Shenhua coal, rice husk, and sewage sludge, respectively. PMID:25638405

  1. Improved low NOx firing systems for pulverized coal combustion

    SciTech Connect

    McCarthy, K.; Laux, S.; Grusha, J.; Rosin, T.; Hausman, G.L.

    1999-07-01

    More stringent emission limits or the addition of post combustion NOx control create the need for improvements of NOx emissions from pulverized coal boilers. Many boilers retrofitted with Low NOx technology during Phase 1 and Phase 2 of the CAAA fail or marginally meet their requirements. Technical solutions range from addition of overfire air and state-of-the-art low NOx burners to low cost additions of combustion enhancements. Regardless of the combustion NOx control method used, stoichiometries local to the burners must be maintained at the designed values at all times to provide high NOx performance at low efficiency loss due to unburned fuel. This paper describes Foster Wheeler's approach to NOx emission improvements for existing low NOx firing systems. The technology to measure air and coal flow individually for each burner and to control the parameters for optimum combustion are presented and discussed. Field experience shows the installation and advantages of the technology.

  2. Combustion of coal gas fuels in a staged combustor

    NASA Technical Reports Server (NTRS)

    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.

  3. COMBUSTION MODIFICATION NOX CONTROLS FOR UTILITY BOILERS. VOLUME I: TANGENTIAL COAL-FIRED UNIT FIELD TEST

    EPA Science Inventory

    The report gives results of an environmental assessment field testing program on a tangential-coal-fired utility boiler. The aim of the program was to measure multimedia emissions changes as a result of applying combustion modification NOx control. Emissions of trace elements, or...

  4. Coal desulfurization by chlorinolysis production and combustion test evaluation of product coals

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Daly, D.

    1982-01-01

    Laboratory-scale screening tests were carried out on coal from Harrison County, Ohio to establish chlorination and hydrodesulfurization conditions for the batch reactor production of chlorinolysis and chlorinolysis-hydrodesulfurized coals. In addition, three bituminous coals, were treated on the lab scale by the chlorinolysis process to provide 39 to 62% desulfurization. Two bituminous coals and one subbituminous coal were then produced in 11 to 15 pound lots as chlorinolysis and hydrodesulfurized coals. The chlorinolysis coals had a desulfurization of 29-69%, reductions in voltatiles and hydrogen. Hydrodesulfurization provided a much greater desulfurization (56-86%), reductions in volatiles and hydrogen. The three coals were combustion tested in the Penn State ""plane flame furnace'' to determine ignition and burning characteristics. All three coals burned well to completion as: raw coals, chlorinolysis processed coals, and hydrodesulfurized coals. The hydrodesulfurized coals experienced greater ignition delays and reduced burning rates than the other coals because of the reduced volatile content. It is thought that the increased open pore volume in the desulfurized-devolatilized coals compensates in part for the decreased volatiles effect on ignition and burning.

  5. Burning of suspended coal-water slurry droplet with oil as combustion additive

    SciTech Connect

    Yao, S.C.; Manwani, P.

    1986-10-01

    Coal-water slurries have been regarded as a potential substitute for heavy fuel oil. Various demonstrations of coal-water slurry combustion have been performed; however, a fundamental understanding of how the combustion process of a slurry fuel is enhanced is still not adequate. The combustion of coal-water mixture droplets suspended on microthermocouples has been investigated. It was found that droplets of lignite coal (which is a noncaking coal) burn effectively; however, droplets of bituminous coal (which is a caking coal) are relatively difficult to burn. During the heat-up of bituminous coal-water slurry droplets may turn to ''popcorn'' and show significant agglomeration. The incomplete combustion of coal-water slurry droplets in furnaces has been reported, and this is a drawback of this process. The objective of the present study is to explore the possibility of enhancing the combustion of coal-water slurry droplets with the use of a combustible emulsified oil.

  6. Coal combustion products 2007 production and use report

    SciTech Connect

    2009-07-01

    The American Coal Ash Association's 2007 Annual Coal Combustion Products (CCP) are derived from data from more than 170 power plants. The amount of CCPs used was 40.55%, a decrease of 2.88% from 2006, attributed to reduced fuel burn and a decrease in demand in the building industry. Figures are given for the production of fly ash, flue gas desulfurization gypsum, bottom ash, FBC ash and boiler slag. The article summarises results of the survey. 1 ref., 1 tab.

  7. Combustion characterization of the blend of plant coal and recovered coal fines

    SciTech Connect

    Singh, Shyam.

    1991-01-01

    The overall objective of this proposed research program is to determine the combustion characteristics of the blend derived from mixing a plant coal and recovered and clean coal fines from the pond. During this study, one plant coal and three blend samples will be prepared and utilized. The blend samples will be of a mixture of 90% plant coal + 10% fines, 85% plant coal + 15% fines, 80% plant coal + 20% fines having particle size distribution of 70% passing through {minus}200 mesh size. These samples' combustion behavior will be examined in two different furnaces at Penn State University, i.e., a down-fired furnace and a drop-tube furnace. The down-fired furnace will be used mainly to measure the emissions and ash deposition study, while the drop tube furnace will be used to determine burning profile, combustion efficiency, etc. This report covers the first quarter's progress. Major activities during this period were focused on finding the plants where a demo MTU column will be installed to prepare the samples needed to characterize the combustion behavior of slurry effluents. Also, a meeting was held at Penn State University to discuss the availability of the laboratory furnace for testing the plant coal/recovered coal fines blends.

  8. FATE OF COAL NITROGEN DURING COMBUSTION

    EPA Science Inventory

    The paper describes the burning of 21 coals, covering all ranks and under a wide variety of conditions, to ascertain the impact of coal properties on the fate of fuel nitrogen. Fuel NC was identified by using a nitrogen-free oxidant consisting of Ar/O2/CO2. It was found that fuel...

  9. NITRIC OXIDE FORMATION DURING PULVERIZED COAL COMBUSTION

    EPA Science Inventory

    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...

  10. Combustion of Illinois coals and chars with natural gas

    SciTech Connect

    Buckius, R.O.

    1991-01-01

    There are applications where the combined combustion of coal and natural gas offers potential advantages over the use of either coal or natural gas alone. For example, low volatile coals or low volatile chars derived from treatment or gasification processes can be of limited use during to their poor flammability characteristics. However, the use of natural gas in conjunction with the solid fuel can provide the necessary volatiles'' to enhance the combustion. In addition, natural gas provides a clean fuel source of fuel which, in cofiring situations, can extend the usefulness of coals with high sulfur content. The addition of natural gas may reduce SO{sub x} emission through increased sulfur retention in the ash and reduce NO{sub x} emissions by varying local stoichiometry and temperature levels. In this research program, studies of combined coal and natural gas combustion will provide particle ignition, burnout rates and ash characterization, that will help clarify the effect of coal and natural gas and identify the controlling parameters and mechanisms.

  11. CO2 emission of coal spontaneous combustion and its relation with coal microstructure, China.

    PubMed

    Wang, Haiyan; Chen Chen; Huang, Tao; Gao, Wei

    2015-07-01

    Coal spontaneous combustion is widely distributed all over the world. CO2 is the main greenhouse gas emitted by coal spontaneous combustion. In the present study characters of CO2 emitted by 10 typical Chinese coal spontaneous combustion and the influence of raw coal functional group on CO2 was studied. CO2 already exists under normal temperature as coal exposed in atmosphere. Under low temperature, the quality of CO2 released by coal spontaneous combustion is relatively small, but tends to increase. And corresponding with it, the oxygen consumption amount is also small. At medium temperature, the oxygen consumption increases rapidly and CO2 mass release rate begins to increase rapidly. Then, CO2 release rate increase rapidly under relatively high temperature (higher than 673 K). Over 873K, concentration of O2 is 6% and release rate of CO2 tends to be steady. It also concluded that mass ratio of CO to CO2 (CO/CO2) during coal spontaneous combustion was lowerthan 0.10 at low temperature. And then, it increased rapidly at medium temperature and reached to top at about 673 K. At 673-873 K, the ratio decreased again, and did not decrease evidently at about 873K. At temperature higher than 873K, the ratio was about 0.13. During the whole testing temperature range, CO/CO2 was not be higher than 0.26, lower than 0.2. This means that release rate of CO2 was much higher than CO during the whole process of coal spontaneous combustion. Moreover, the gas release quantity of CO2 is positively related with carbony content in raw coal. Carbonyl and carboxyl were both material basis of CO2. PMID:26364484

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

    SciTech Connect

    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)

  13. Combustion of coal-gas fuels in a staged combustor

    SciTech Connect

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

    1982-01-01

    Gaseous fuels produced from coal resources have been considered for use in industrial gas turbines. Such fuels generally have heating values much lower than the typical gaseous fuel, natural gas; the low heating value could result in unstable or inefficient combustion. Additionally, coal gas fuels may contain ammonia which if oxidized in an uncontrolled manner could result in unacceptable NO/sub x/ exhaust emission levels. Previous investigations have indicated that staged, rich-lean combustion represents a desirable approach to achieve stable, efficient, low NO/sub x/ emission operation for coal-derived liquid fuels containing up to 0.8-wt % nitrogen. An experimental program has been 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% ammonia are presented. The test results permit the following conclusions to be drawn: (1) Staged, rich-lean combustion represents the desirable approach to achieve ultra-low NO/sub x/ and CO emissions for coal gas fuels with heating values of 210 kJ/mol (238 Btu/scf) or higher. (2) Lean combustion represents the desirable approach to achieve ultra-low NO/sub x/ and CO emissions for coal gas fuels with low heating values (84 kJ/mol (95 Btu/scf)). (3) Staged combustion has the ability to limit NH/sub 3/ to NO/sub x/ conversion rates to less than 5%. NO/sub x/ emissions below the EPA limit can readily be achieved.

  14. Coal-feeding mechanism for a fluidized bed combustion chamber

    DOEpatents

    Gall, Robert L.

    1981-01-01

    The present invention is directed to a fuel-feeding mechanism for a fluidized bed combustor. In accordance with the present invention a perforated conveyor belt is utilized in place of the fixed grid normally disposed at the lower end of the fluidized bed combustion zone. The conveyor belt is fed with fuel, e.g. coal, at one end thereof so that the air passing through the perforations dislodges the coal from the belt and feeds the coal into the fluidized zone in a substantially uniform manner.

  15. Combustion of coal/water mixtures with thermal preconditioning

    SciTech Connect

    Novack, M.; Roffe, G.; Miller, G.

    1987-07-01

    Thermal preconditioning is a process in which coal/water mixtures are vaporized to produce coal/steam suspensions, and then superheated to allow the coal to devolatilize producing suspensions of char particles in hydrocarbon gases and steam. This final product of the process can be injected without atomization, and burned directly in a gas turbine combustor. This paper reports on the results of an experimental program in which thermally preconditioned coal/water mixture was successfully burned with a stable flame in a gas turbine combustor test rig. Tests were performed at a mixture flowrate of 300 lb/hr and combustor pressure of 8 atm. The coal/water mixture was thermally preconditioned and injected into the combustor over a temperature range from 340/sup 0/F to 600/sup 0/F, and combustion air was supplied at between 600/sup 0/F to 725/sup 0/F. Test durations varied between 10 and 20 min. Major results of the combustion testing were that: A stable flame was maintained over a wide equivalence ratio range, between phi = 2.2 (rich) and 0.2 (lean); and combustion efficiency of over 99 percent was achieved when the mixture was preconditioned to 600/sup 0/F and the combustion air preheated to 725/sup 0/F. Measurements of ash particulates, captured in the exhaust sampling probe located 20 in. from the injector face, show typical sizes collected to be about 1 ..mu..m, with agglomerates of these particulates to be not more than 8 ..mu..m. The original mean coal particle size for these tests, prior to preconditioning, was 25 ..mu..m. Results of additional tests showed that one third of the sulfur contained in the solids of a coal/water mixture with 3 percent sulfur was evolved in gaseous form (under mild thermolized conditions) mainly as H/sub 2/S with the remainder as light mercaptans.

  16. PULVERIZED COAL COMBUSTION: POLLUTANT FORMATION AND CONTROL, 1970-1980

    EPA Science Inventory

    The report documents the support role of EPA's Air and Energy Engineering Research Laboratory in the major research effort directed by EPA in the l970s to understand pollutant formation during pulverized coal combustion (PCC). nderstanding the conversion of fuel nitrogen to nitro...

  17. PULVERIZED COAL COMBUSTION: POLLUTANT FORMATION AND CONTROL, 1970-1980

    EPA Science Inventory

    The report documents the support role of EPA's Air and Energy Engineering Research Laboratory in the major research effort directed by EPA in the l970s to understand pollutant formation during pulverized coal combustion (PCC). Understanding the conversion of fuel nitrogen to nit...

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

    PubMed

    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. PMID:27136608

  19. Control of Trace Metal Emissions During Coal Combustion

    SciTech Connect

    Thomas C. Ho

    1996-10-01

    Emissions of toxic trace metals in the form of metal fumes or submicron particulate from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDS) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor.

  20. Control of Trace Metal Emissions During Coal Combustion

    SciTech Connect

    Thomas C. Ho

    1997-10-01

    Emissions of toxic trace metals in the form of metal fumes or submicron particulates from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDs) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor. The project was started on July 1, 1994 and this is the thirteenth quarterly technical progress report. Specifically, the following progress has been made during this performance period from July 1, 1997 through September 30, 1997.

  1. Control of Trace Metal Emissions During Coal Combustion

    SciTech Connect

    Thomas C. Ho

    1997-01-01

    Emissions of toxic trace metals in the form of metal fumes or submicron particulates from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDs) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor.

  2. Control of Trace Metal Emissions During Coal Combustion

    SciTech Connect

    Thomas C. Ho

    1997-07-01

    Emissions of toxic trace metals in the form of metal fumes or submicron particulates from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDs) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor.

  3. Control of Trace Metal Emissions During Coal Combustion

    SciTech Connect

    Thomas C. Ho

    1997-04-01

    Emissions of toxic trace metals in the form of metal fumes or submicron particulates from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDs) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor.

  4. Thermochemical and trace element behavior of coal gangue, agricultural biomass and their blends during co-combustion.

    PubMed

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

    2014-08-01

    The thermal decomposition behavior of coal gangue, peanut shell, wheat straw and their blends during combustion were determined via thermogravimetric analysis. The coal gangue/agricultural biomass blends were prepared in four weight ratios and oxidized under dynamic conditions from room temperature to 1000 °C by various heating rates. Kinetic models were carried out to evaluate the thermal reactivity. The overall mass balance was performed to assess the partition behavior of coal gangue, peanut shell and their blends during combustion in a fixed bed reactor. The decomposition processes of agricultural biomass included evaporation, release of volatile matter and combustion as well as char oxidation. The thermal reactivity of coal gangue could be improved through the addition of agricultural biomass in suitable proportion and subsequent appropriate heating rate during combustion. In combination with the heating value and base/acid ratio limitations, a blending ratio of 30% agricultural biomass is conservatively selected as optimum blending. PMID:24914998

  5. Mercury emissions and species during combustion of coal and waste

    SciTech Connect

    Hong Yao; Guangqian Luo; Minghou Xu; Tamotsu Kameshima; Ichiro Naruse

    2006-10-15

    The behaviors of mercury evolution for three types of coal and three types of dried sewage sludge are studied using a thermogravimetric (TG) analyzer. The mercury speciations in the flue gas from coal and sludge combustion are also analyzed by implementing a horizontal electrically heated tube furnace. Furthermore, the kinetic calculations of mercury oxidizing processes are carried out using the software package CHEMKIN in order to interpret the homogeneous mechanism of mercury oxidization. The results obtained show that the sulfur content in the sludge inhibits the evolution of mercury at low temperature if the Cl concentration is high enough. Chlorine enhances mercury evolution in the coal combustion, whereas there is no relationship when the Cl concentration is high. Fixed carbon content plays a role in depression of the mercury evolution. Formation of oxidized mercury (HgCl{sub 2}) does not relate to the chlorine concentration in the raw coal and sludge. Whereas the ash and sulfur content in the sludge affects the Hg oxidization, kinetic calculations show that HgCl, Cl{sub 2}, and HOCl formation is important in producing the oxidized mercury during combustion of coal and sludge at 873 K. A suitable temperature for Hg oxidization when Cl{sub 2} is the oxidization resource is 700-1200 K. 32 refs., 10 figs., 5 tabs.

  6. The role of combustion diagnostics in coal quality impact and NO{sub x} emissions field test programs

    SciTech Connect

    Thompson, R.E.; Dyas, B.

    1995-03-01

    Many utilities are examining low sulfur coal or coal blending options to comply with the Clean Air Act Amendment SO{sub 2} emission limits. Test burns have been conducted with the more promising candidate coals to characterize the potential impact of a change in coal quality on boiler operation and performance. Utilities are also under considerable pressure to evaluate NO{sub x} control options and develop a compliance plan to meet strict NO{sub x} regulations, particularly in high population density metropolitan areas on the Eastern seaboard. Field test programs have been conducted to characterize baseline NO{sub x} emissions, evaluate the NO{sub x} reduction potential of combustion modifications, and assess the potential of combustion tuning as an alternative to burner replacement. Coal quality impacts (slagging, fouling, heat absorption, ash removal) and NO{sub x} emissions are both strongly dependent upon the coal combustion process and site-specific boiler firing practices. Non-uniform combustion in the burner region can result in adverse ash deposition characteristics, carbon carryover problems, high furnace exit gas temperatures, and NO{sub x}emission characteristics that are not representative of the coal or the combustion equipment. Advanced combustion diagnostic test procedures have been developed to evaluate and improve burner zone combustion uniformity, even in cases where the coal flow to the individual burners may be non-uniform. The paper outlines a very practical solving approach to identifying combustion related problems that affect ash deposition and NO{sub x} emissions. The benefits of using advanced diagnostic instrumentation to identify problems and tune combustion conditions is illustrated using test data from recent quality field test programs.

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

    NASA Astrophysics Data System (ADS)

    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

  8. Method for increasing the calorific value of gas produced by the in situ combustion of coal

    DOEpatents

    Shuck, Lowell Z.

    1978-01-01

    The present invention relates to the production of relatively high Btu gas by the in situ combustion of subterranean coal. The coal bed is penetrated with a horizontally-extending borehole and combustion is initiated in the coal bed contiguous to the borehole. The absolute pressure within the resulting combustion zone is then regulated at a desired value near the pore pressure within the coal bed so that selected quantities of water naturally present in the coal will flow into the combustion zone to effect a hydrogen and carbon monoxide-producing steam-carbon reaction with the hot carbon in the combustion zone for increasing the calorific value of the product gas.

  9. Electricity from coal and utilization of coal combustion by-products

    SciTech Connect

    Demirbas, A.

    2008-07-01

    Most electricity in the world is conventionally generated using coal, oil, natural gas, nuclear energy, or hydropower. Due to environmental concerns, there is a growing interest in alternative energy sources for heat and electricity production. The major by-products obtained from coal combustion are fly ash, bottom ash, boiler slag, and flue gas desulfurization (FGD) materials. The solid wastes produced in coal-fired power plants create problems for both power-generating industries and environmentalists. The coal fly ash and bottom ash samples may be used as cementitious materials.

  10. Toxic Substances From Coal Combustion - Phase I Coal Selection and Chaacterization

    SciTech Connect

    A. Kolker; A. Sarofim; C.A. Palmer; C.L. Senior; F.E. Huggins; G.P. Huffman; I. Olmez; N. Shah; R. Finkelman; S. Crowley; T. Zeng

    1998-07-16

    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. Over the past decade, a large database identifying the partitioning and emitted concentrations of several toxic metals on the list of HAPs has been developed. Laboratory data have also been generated to help define the general behavior of several elements in combustion systems. These data have been used to develop empirical and probabalistic models to predict emissions of trace metals from coal-fired power plants. While useful for providing average emissions of toxic species, these empirically based models fail when extrapolated beyond their supporting database. This represents a critical gap; over the coming decades, new fuels and combustion systems will play an increasing role in our nation's power generation system. For example, new fuels, such as coal blends or beneficiated fuels, new operating conditions, such as low-NO burners or staged combustion, or new power x systems, for example, those being developed under the DoE sponsored Combustion 2000 programs and integrated gasification combined cycle (IGCC) systems, are all expected to play a role in power generation in the next century. The need for new predictive tools is not limited to new combustion systems, however. Existing combustion systems may have to employ controls for HAPs, should regulations be imposed. Testing of new control methods, at pilot and full scale, is expensive. A sound under-standing of the chemical transformations of both organic and inorganic HAPs will promote the development of new control methods in a cost-effective manner. To ensure that coal-fired power generation proceeds in an environmentally benign fashion, methods for the prediction and

  11. Laser diagnostics of mineral matter and combustion processes in coal

    SciTech Connect

    Venkateswarlu, P.; George, M.C.; Sekhar, P.C.; Subbarao, V.

    1989-01-01

    This is the third report on this project. During the period covered by the first two reports (October 1, 1987 through August 30, 1988) a sample of low sulfur powdered coal was heated under vacuum from 25 to 1000{degrees}C at a heating rate of 5{degrees}C per minute. The vapors generated were analyzed by a Balzer Quadrupole Mass Spectrometer model QMG 511. The analysis showed that the major constituents of the vapors are aliphatic hydrocarbons. A second set of experiments were carried out to determine the mineral constituents in ash obtained by heating coal in a porcelain crucible at 400--500{degrees}C in a muffle furnace until all the coal was oxidized. Model 3030 Perkin Elmer Atomic Absorption Spectrophotometer was used with appropriate hollow cathode lamps. A dozen elements were identified. Al, Na, K and Fe were the most prominent. During this period we have made an extensive series of measurements on laser induced combustion of coal pellets made from coal powder. C{sub 2}, CN, CO, Na and K were identified from the spectra. We have also fabricated a burner for the study of coal combustion using laser spectroscopic techniques. 1 ref., 4 figs.

  12. Plasma Torch for Plasma Ignition and Combustion of Coal

    NASA Astrophysics Data System (ADS)

    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. Formation and use of coal combustion residues from three types of power plants burning Illinois coals

    USGS Publications Warehouse

    Demir, I.; Hughes, R.E.; DeMaris, P.J.

    2001-01-01

    Coal, ash, and limestone samples from a fluidized bed combustion (FBC) plant, a pulverized coal combustion (PC) plant, and a cyclone (CYC) plant in Illinois were analyzed to determine the combustion behavior of mineral matter, and to propose beneficial uses for the power plant ashes. Pyrite and marcasite in coal were converted during combustion to glass, hematite and magnetite. Calcite was converted to lime and anhydrite. The clay minerals were altered to mullite and glass. Quartz was partially altered to glass. Trace elements in coal were partially mobilized during combustion and, as a result, emitted into the atmosphere or adsorbed on fly ash or on hardware on the cool side of the power plants. Overall, the mobilities of 15 trace elements investigated were lower at the FBC plant than at the other plants. Only F and Mn at the FBC plant, F, Hg, and Se at the PC plant and Be, F, Hg, and Se at the CYC plant had over 50% of their concentrations mobilized. Se and Ge could be commercially recovered from some of the combustion ashes. The FBC ashes could be used as acid neutralizing agents in agriculture and waste treatment, and to produce sulfate fertilizers, gypsum wall boards, concrete, and cement. The PC and CYC fly ashes can potentially be used in the production of cement, concrete, ceramics, and zeolites. The PC and CYC bottom ashes could be used in stabilized road bases, as frits in roof shingles, and perhaps in manufacturing amber glass. ?? 2001 Elsevier Science Ltd. All rights reserved.

  14. [Lead emission amount from coal combustion and its environment effect in Xi'an City].

    PubMed

    Luo, Kunli; Wang, Douhu; Tan, Jianan; Wang, Lizheng; Feng, Fujian; Li, Ribang

    2002-01-30

    For study the lead emission amount from coal combustion and its environment effect, the lead content of coal, ash and cinder of power station and coal-fired boiler, the lead content of dusts in the period of heating time and the non-heating time in Xi'an City were studied in this paper. The results show that amount of lead emission from 1 ton coal combustion, which lead content in coal was 30 g, was 20 g in atmosphere. The rate of lead emission of coal combustion was about 66%. About 10 million tons of coal was straight burning every year in Xi'an City and suburb, those coal mainly come from Permo-Carboniferous coal in Weibei coal mine, Shaanxi, their average lead content was 30 mg/kg. So the total lead emission from coal combustion to atmosphere was about 200 t annually in Xi'an City. PMID:11987396

  15. Coal systems - A gateway to predictive assessments of coal production

    USGS Publications Warehouse

    Milici, R.

    2004-01-01

    Current federal and State coal assessments estimate resources in the ground, resources available for mining, and economically recoverable resources. None of these assessments predict the amount of coal that may be produced from an assessed area in the near future (???20 years). Predictive assessments of coal production would be based on an understanding of the regional coal geology (coal systems), potential demand, and knowledge of the mining history of the region. The output of the predictive assessment would be a supply curve - a probability distribution of the amount of coal expected to be produced from current and new mines during the assessment period.

  16. [Study on the calcium-based sorbent for removal fluorine during coal combustion].

    PubMed

    Li, Shu-ling; Qi, Qing-jie; Liu, Jian-zhong; Cao, Xin-yu; Zhou, Jun-hu; Cen, Ke-fa

    2004-03-01

    In the paper, the reaction of CaO-HF and fluorine removal mechanics at high temperature by blending calcium-based sorbents with coal during coal combustion were discussed, and test results about fluorine retention during coal combustion in fluidized bed and chain-grate furnace were reported. The results identified that lime and calcium-based sorbets developed can restratin the emission of fluorine during coal combustion. The efficiency of fluorine removal can reach 66.7%-70.0% at Ca/F 60-70 by blending lime with coal in fluidized bed combustion, and the efficiency of fluorine removal are between 57.32% and 75.19% by blending calcium-based sorbets with coal in chain-grate furnace combustion. Blending CaO or lime with coal during coal combustion can remove SO2 and HF simultaneously. PMID:15202259

  17. CHARACTERISTICS OF SINGLE PARTICLE COAL COMBUSTION

    EPA Science Inventory

    The paper discusses the measurement of the burning history of single coal particles, using a two-color optical pyrometer. rom intensity traces at two wavelengths, information on burning times and temperatures, the duration of a volatile flame, and projected areas was obtained for...

  18. Oxy-combustion of pulverized coal : modeling of char-combustion kinetics.

    SciTech Connect

    Shaddix, Christopher R.; Haynes, Brian S.; Geier, Manfred

    2010-09-01

    In this study, char combustion of pulverized coal under oxy-fuel combustion conditions was investigated on the basis of experimentally observed temperature-size characteristics and corresponding predictions of numerical simulations. Using a combustion-driven entrained flow reactor equipped with an optical particle-sizing pyrometer, combustion characteristics (particle temperatures and apparent size) of pulverized coal char particles was determined for combustion in both reduced oxygen and oxygen-enriched atmospheres with either a N{sub 2} or CO{sub 2} bath gas. The two coals investigated were a low-sulfur, high-volatile bituminous coal (Utah Skyline) and a low-sulfur subbituminous coal (North Antelope), both size-classified to 75-106 {micro}m. A particular focus of this study lies in the analysis of the predictive modeling capabilities of simplified models that capture char combustion characteristics but exhibit the lowest possible complexity and thus facilitate incorporation in existing computational fluid dynamics (CFD) simulation codes. For this purpose, char consumption characteristics were calculated for char particles in the size range 10-200 {micro}m using (1) single-film, apparent kinetic models with a chemically 'frozen' boundary layer, and (2) a reacting porous particle model with detailed gas-phase kinetics and three separate heterogeneous reaction mechanisms of char-oxidation and gasification. A comparison of model results with experimental data suggests that single-film models with reaction orders between 0.5 and 1 with respect to the surface oxygen partial pressure may be capable of adequately predicting the temperature-size characteristics of char consumption, provided heterogeneous (steam and CO{sub 2}) gasification reactions are accounted for.

  19. Oxy-combustion of pulverized coal : modeling of char combustion kinetics.

    SciTech Connect

    Shaddix, Christopher R.; Haynes, Brian S.; Geier, Manfred

    2010-09-01

    In this study, char combustion of pulverized coal under oxy-fuel combustion conditions was investigated on the basis of experimentally observed temperature-size characteristics and corresponding predictions of numerical simulations. Using a combustion-driven entrained flow reactor equipped with an optical particle-sizing pyrometer, combustion characteristics (particle temperatures and apparent size) of pulverized coal char particles was determined for combustion in both reduced oxygen and oxygen-enriched atmospheres with either a N{sub 2} or CO{sub 2} bath gas. The two coals investigated were a low-sulfur, high-volatile bituminous coal (Utah Skyline) and a low-sulfur subbituminous coal (North Antelope), both size-classified to 75-106 {micro}m. A particular focus of this study lies in the analysis of the predictive modeling capabilities of simplified models that capture char combustion characteristics but exhibit the lowest possible complexity and thus facilitate incorporation in existing computational fluid dynamics (CFD) simulation codes. For this purpose, char consumption characteristics were calculated for char particles in the size range 10-200 {micro}m using (1) single-film, apparent kinetic models with a chemically 'frozen' boundary layer, and (2) a reacting porous particle model with detailed gas-phase kinetics and three separate heterogeneous reaction mechanisms of char-oxidation and gasification. A comparison of model results with experimental data suggests that single-film models with reaction orders between 0.5 and 1 with respect to the surface oxygen partial pressure may be capable of adequately predicting the temperature-size characteristics of char consumption, provided heterogeneous (steam and CO{sub 2}) gasification reactions are accounted for.

  20. Sulfur emission from Victorian brown coal under pyrolysis, oxy-fuel combustion and gasification conditions.

    PubMed

    Chen, Luguang; Bhattacharya, Sankar

    2013-02-01

    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. PMID:23301852

  1. Combustion characterization of beneficiated coal-based fuels

    SciTech Connect

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

    1990-08-01

    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, conbustion, and ash deposition tests; pilot-scale combustion and ash effects tests; and full-scale combustion tests. Subcontractors to CE to perform parts of the test work are the Massachusetts Institute of Technology (MIT), Physical Sciences, Inc. Technology Company (PSIT) and the University of North Dakota Energy and Environmental Research Center (UNDEERC). Twenty fuels will be characterized during the three-year base program: three feed coals, fifteen BCFs, and two conventionally cleaned coals for the full-scale tests. Approximately nine BCFs will be in dry ultra-fine coal (DUC) form, and six BCFs will be in coal-water fuel (CWF) form. Additional BCFs would be characterized during optional project supplements.

  2. Influence of sulfur in coals on char morphology and combustion

    SciTech Connect

    Marsh, H.

    1991-01-01

    During coal carbonization (pyrolysis), as during the combustion process of pulverized coal in a combustor, not all of the sulfur is released. Significant proportions become pat of the structure of the resultant coke and char. The combustion process of the char within the flames of the combustor in influenced dominantly by char morphology. This, in turn, controls the accessibility of oxidizing gases to the surfaces of the carbonaceous substance of the char. Mineral matter content, its extent and state of distribution, also exerts an influence on char morphology created during pyrolysis/carbonization. This complexity of coal renders it a very difficult material to study, systematically, to distinguish and separate out the contributing factors which influence combustion characteristics. Therefore, in such circumstances, it is necessary to simplify the systems by making use of model chars/cokes/carbons which can be made progressively more complex, but in a controlled way. In this way complicating influence in chars from coals can be eliminated, so enabling specific influences to be studied independently. It is important to note that preliminary work by Marsh and Gryglewicz (1990) indicated that levels of sulfur of about 3 to 5 wt % can reduce reactivities by 10 to 25%. The overall purpose of the study is to provide meaningful kinetic data to establish, quantitatively, the influence of organically-bound sulfur on the reactivity of carbons, and to ascertain if gasification catalysts are effective in the preferential removal of sulfur from the chars.

  3. Geochemical database of feed coal and coal combustion products (CCPs) from five power plants in the United States

    USGS Publications Warehouse

    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.

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

    DOEpatents

    McMillian, Michael H.

    1992-01-01

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

  5. Mineralogical characterization of ambient fine/ultrafine particles emitted from Xuanwei C1 coal combustion

    NASA Astrophysics Data System (ADS)

    Lu, Senlin; Hao, Xiaojie; Liu, Dingyu; Wang, Qiangxiang; Zhang, Wenchao; Liu, Pinwei; Zhang, Rongci; Yu, Shang; Pan, Ruiqi; Wu, Minghong; Yonemochi, Shinich; Wang, Qingyue

    2016-03-01

    Nano-quartz in Xuanwei coal, the uppermost Permian (C1) coal deposited in the northwest of Yuanan, China, has been regarded as one of factors which caused high lung cancer incidence in the local residents. However, mineralogical characterization of the fine/ultrafine particles emitted from Xuanwei coal combustion has not previously been studied. In this study, PM1 and ultrafine particles emitted from Xuanwei coal combustion were sampled. Chemical elements in the ambient particles were analyzed by inductively coupled plasma mass spectrometry (ICP-MS), and mineralogical characterization of these ambient particles was investigated using scanning electronic microscopy (SEM/EDX) and transmission electronic microscopy, coupled with energy-dispersive spectroscopy (TEM/EDX). Our results showed that the size distribution of mineral particles from the coal combustion emissions ranged from 20 to 200 nm. Si-containing particles and Fe-containing particles accounted for 50.7% of the 150 individual particles measured, suggesting that these two types of particles were major minerals in the ambient particles generally. The nano-mineral particles were identified as quartz (SiO2) and gypsum (CaSO4) based on their crystal parameters and chemical elements. Additionally, there also existed unidentified nano-minerals. Armed with these data, toxicity assessments of the nano-minerals will be carried out in a future study.

  6. Northern and Central Appalachian region assessment: The Pittsburgh coal bed

    SciTech Connect

    Ruppert, L.; Tewalt, S.; Bragg, L.

    1996-12-31

    Approximately 40% of the Nation`s coal is produced in the six states (Ohio, Pennsylvania, West Virginia, Maryland, Virginia, and Kentucky) that occupy parts of the Northern and Central Appalachian region. Coal is, and will continue to be, the primary energy commodity in this region where more than 50 coal beds and coal zones are currently being mined. About one-half of the productions is from just eight coal beds or zones. Three of these, the Pittsburgh and Upper Freeport coal beds and the Kittanning coal zone, are located in the northern part of the region. The remaining beds or zones, the Pond Creek, Fire Clay, Alma, Upper Elkhorn No. 3, and the Pocahontas No. 3, are located primarily in the central part of the region. This study is designed to utilize the data and expertise existing within the USGS and the State Geological Surveys to produce bed-specific, digital, coal resource assessments for most of the top-producing coal beds and coal zones. Unlike past USGS assessments, this study will emphasize not only the quantity of coal but also the quality of the coal. Particular attention will be paid to the geochemical parameters that are thought to adversely effect combustion characteristics and possibly have adverse effects on the environment, including ash yield, sulfur, calorific value, and, the elements listed in the 1990 Clean Air Act Amendments. Geochemical databases produced for the assessed beds will be augmented by new, representative, coal analyses of major, minor, and trace elements. Products will include stratigraphic and geochemical data bases, original and remaining source calculations, and comprehensive digital maps at a scale of 1:250,000 or 1:500,000 of crop-line, coal thickness, coal structure, overburden thickness, mined-out areas, and geochemistry for each assessed coal beds.

  7. Evaluation of catalytic combustion of actual coal-derived gas

    NASA Technical Reports Server (NTRS)

    Blanton, J. C.; Shisler, R. A.

    1982-01-01

    The combustion characteristics of a Pt-Pl catalytic reactor burning coal-derived, low-Btu gas were investigated. A large matrix of test conditions was explored involving variations in fuel/air inlet temperature and velocity, reactor pressure, and combustor exit temperature. Other data recorded included fuel gas composition, reactor temperatures, and exhaust emissions. Operating experience with the reactor was satisfactory. Combustion efficiencies were quite high (over 95 percent) over most of the operating range. Emissions of NOx were quite high (up to 500 ppm V and greater), owing to the high ammonia content of the fuel gas.

  8. Transformations of inorganic coal constituents in combustion systems

    SciTech Connect

    Helble, J.J.; Srinivasachar, S.; Wilemski, G.; Boni, A.A. ); Kang, Shin-Gyoo; Sarofim, A.F.; Graham, K.A.; Beer, J.M. ); Peterson, T.W.; Wendt, J.O.L.; Gallagher, N.B.; Bool, L. ); Huggins, F.E.; Huffman, G.P.; Shah, N.; Shah, A. (Kentucky Univ., Lexingt

    1992-11-01

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

  9. Combustion of coal/water mixtures with thermal preconditioning

    SciTech Connect

    Novack, M.; Roffe, G.; Miller, G.

    1987-01-01

    Thermal preconditioning is a process in which coal/water mixtures are vaporized to produce coal/steam suspensions, and then superheated to allow the coal to devolitalize producing suspensions of char particles in hydrocarbon gases and steam. This final product of the process can be injected without atomization, and burned directly in a gas turbine combustor. This paper reports on the results of an experimental program in which thermally preconditioned coal/water mixture was successfully burned with a stable flame in a gas turbine combustor test rig. Tests were performed at a mixture flowrate of 300 1b/hr and combustor pressure of 8 atmospheres. The coal/water mixture was thermally preconditioned and injected into the combustor over a temperature range from 350/sup 0/F to 600/sup 0/F, and combustion air was supplied at between 600/sup 0/F to 725/sup 0/F. Test durations varied between 10 to 20 minutes. The original mean coal particle size for these tests, prior to preconditioning was 25 microns. Results of additional tests showed that one-third of the sulfur contained in the solids of a coal/water mixture with 3 percent sulfur were evolved in gaseous form (under mild thermolized conditions) mainly as H/sub 2/S with the remainder as light mercaptans.

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

    PubMed

    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. PMID:25997009

  11. Balancing act creating the right regulation for coal combustion waste

    SciTech Connect

    Manuel, J.

    2009-11-15

    The December 2008 collapse of a coal ash pond in Tennessee threw safe management of coal combustion waste (CCW) into the spotlight. Millions of tons of CCW are produced in the United States each year, and a large percentage of that is recycled. The US Environmental Protection Agency is pursuing a host of initiatives that could directly or indirectly affect the disposition of CCW. States, too, are taking a look at how they regulate CCW. Among the options is the possibility of regulating CCW under the Resource Conservation and Recovery Act, a move that could have far-reaching implications for both the recycling and the disposal of this waste.

  12. Beneficial use of coal combustion products continues to grow

    SciTech Connect

    MacDonald, M.

    2008-07-01

    In August 2007 the American Coal Ash Association (ACAA) released results of the Coal Combustion Products Production (CCP) and use survey. Production was 124,795,000 tons while beneficial use was 54,203,000 tons, a utilization rate of over 43%, 3% higher than in 2005. The article includes graphs of 40 years of CCP production and use and projected trade of CCP utilization until 2011. It also gives 2006 figures for Production and use of fly ash, bottom ash, boiler slag, FGD gypsum and other FGD products, and FBC ash. 3 refs., 3 figs.

  13. HIGH PRESSURE COAL COMBUSTION KINETICS PROJECT

    SciTech Connect

    Chris Guenther, Ph.D.

    2003-01-28

    SRI has completed the NBFZ test program, made modification to the experimental furnace for the HPBO test. The NBFZ datasets provide the information NEA needs to simulate the combustion and fuel-N conversion with detailed chemical reaction mechanisms. BU has determined a linear swell of 1.55 corresponding to a volumetric increase of a factor of 3.7 and a decrease in char density by the same factor. These results are highly significant, and indicate significantly faster burnout at elevated pressure due to the low char density and large diameter.

  14. Detection of smoldering combustion of coal with an odor meter

    SciTech Connect

    Edwards, J.C.

    1995-05-01

    A commercially available odor meter was evaluated as a detector of smoldering coal combustion, and compared with incipient carbon monoxide (CO) and hydrogen sulfide (H{sub 2}S) detection and a commercially available ionization-type smoke detector. Ten smoldering coal combustion experiments were conducted. For eight of the experiments, Pittsburgh seam coal with an average particle diameter of approximately 5 cm was heated by embedded electrical strip heaters. For two of the experiments mine size Pittsburgh seam coal was heated. Heating rates of 0.5, 0.8, and 1.1. kw were selected to provide experimental conditions characteristic of very slow and moderately fast heating for coal sample mass between 3 and 10 kg. It was found that the odor meter and smoke detector alarm had a good correlation, with the odor meter alarm occurring prior to the smoke alarm in four of the ten experiments. The odor meter gave an increase in its output signal above ambient equivalent to detecting 1 ppm of H{sub 2}S (ten times the odor threshold of H{sub 2}S) as an alarm value. This observed odor meter response occurred prior to the electrochemical detection of H{sub 2}S for five of the six experiments for which it was evaluated. In all six experiments for which the smoke optical density was evaluated, it was less than 0.023 m{sup -1} prior to the odor meter reaching alarm. In each of the eight experiments with 5 cm diameter coal particles the CO exceeded 5 ppm at odor meter alarm, while for the two experiments with mine size coal the CO was less than 3 ppm at odor meter alarm. The odor meter, as tested, is not a significant improvement over smoke and CO detectors. Because the odor meter responds to a variety of chemical compounds, with suitable modification and increased sensitivity it may be useful for detection of mine fires and thereby enhance mine safety.

  15. Development of coal combustion sensitivity test for smoke detectors

    SciTech Connect

    Edwards, J.C.; Morrow, G.S.

    1995-09-01

    Standard smoldering and flaming combustion tests using small coal samples have been developed by the US Bureau of Mines as a method to evaluate the response of a smoke detector. The tests are conducted using a standard smoke box designed and constructed according to Underwriters Laboratories. The tests provide a standard, easily reproducible smoke characteristic for smoldering and flaming coal combustion, based upon a comparison of the smoke optical density and the response of a standard ionization chamber to the smoke. With these standard tests, the range of threshold limits for the response of a smoke detector and the detector`s reliability can be evaluated for nearly identical smoke visibility and smoke physical characteristics. The detector`s threshold response limits and reliability need to be well defined prior to the instrument`s use as part of a mine fire warning system for improved mine safety.

  16. Near-extinction and final burnout in coal combustion

    SciTech Connect

    Hurt, R.H.; Davis, K.A.

    1994-02-01

    The late stages of char combustion have a special technological significance, as carbon conversions of 99% or greater are typically required for the economic operation of pulverized coal fired boilers. In the present article, two independent optical techniques are used to investigate near-extinction and final burnout phenomenas. Captive particle image sequences, combined with in situ optical measurements on entrained particles, provide dramatic illustration of the asymptotic nature of the char burnout process. Single particle combustion to complete burnout is seen to comprise two distinct stages: (1) a rapid high-temperature combustion stage, consuming about 70% of the char carbon and ending with near-extinction of the heterogeneous reactions due to a loss of global particle reactivity, and (2) a final burnout stage occurring slowly at lower temperatures. For particles containing mineral matter, the second stage can be further subdivided into: (2a) late char combustion, which begins after the near-extinction event, and converts carbon-rich particles to mixed particle types at a lower temperature and a slower rate; and (2b) decarburization of ash -- the removal of residual carbon inclusions from inorganic (ash) frameworks in the very late stages of combustion. This latter process can be extremely slow, requiring over an order of magnitude more time than the primary rapid combustion stage. For particles with very little ash, the loss of global reactivity leading to early near-extinction is clearly related to changes in the carbonaceous char matrix, which evolves over the course of combustion. Current global kinetic models used for the prediction of char combustion rates and carbon burnout in boilers do not predict the asymptotic nature of char combustion. More realistic models accounting for the evolution of char structure are needed to make accurate predictions in the range of industrial interest.

  17. EFFECTS OF IRON CONTENT IN COAL COMBUSTION FLY ASHES ON SPECIATION OF MERCURY

    EPA Science Inventory

    The paper discusses the effects of iron content in coal combustion fly ashes on speciation of mercury. (NOTE: The chemical form of mercury species in combustion flue gases is an important influence on the control of mercury emissions from coal combustion). The study focused on th...

  18. HIGH PRESSURE COAL COMBUSTION KINETICS PROJECT

    SciTech Connect

    Chris Guenther

    2002-10-28

    The modifications to the SRT-RCFR facility described in the June report were completed. As a result of these changes, the furnace hot zone was increased in length from 7 cm to 15.5 cm. The injector region of the furnace, providing entrainment and sheath flows, was unchanged, while the flow path from the exit of the furnace to the sample collection section was shortened by approximately 10 cm. The modified facility was used to resume testing of Pittsburgh No. 8 coal at 10 atm. The first goal was to confirm that the facility now provides true secondary pyrolysis test conditions. That is, the tar product should be completely converted to soot even in the absence of oxygen in the gas stream. We have now performed four tests with pure argon carrier gas, and have consistently observed voluminous soot product with little or no evidence of tar. Thus, this objective was met. The clogging problems for Pittsburgh No. 8 coal under secondary pyrolysis test conditions may preclude achieving this data point. In that case, we will make measurements under oxidizing conditions, which are expected to eliminate the clogging, and to gradually reduce the oxygen content to the point where product yields can reliably be extrapolated to the zero oxygen case.

  19. [Development of mercury emission inventory from coal combustion in China].

    PubMed

    Jiang, Jing-kun; Hao, Ji-ming; Wu, Ye; Streets, David G; Duan, Lei; Tian, He-zhong

    2005-03-01

    Mercury emission inventory by province from coal combustion in China was developed by combining fuel consumption, mercury content in fuel and emission factors after combustion in this study. The study is intended to provide an understanding of mercury transformation, transportation and deposition in atmosphere, as well as propose measures to control mercury pollution in China. Mercury emission sources were classified into 65 categories by economic sectors, fuel types, boiler types and pollution control technologies. For two different data sets of mercury content in coal the total amounts of mercury released into atmosphere in 2000 in China were estimated at about 161.6 tons and 219.5 tons, respectively. The biggest three source sectors were industry, power plants, and residential use, contributing 46%, 35% and 14% of total mercury emissions, respectively. The shares of elemental mercury (Hg0), oxidized mercury (Hg2+ ) and particulate mercury (Hgp) were 16% , 61% and 23% , respectively. The spatial distribution of mercury emissions from coal combustion in China is not uniform. Henan, Shanxi, Hebei, Liaoning and Jiangsu contributed large amounts of mercury emissions, exceeding 10t x a(- 1). PMID:16004296

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

    USGS Publications Warehouse

    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.

  1. Catalytic effects of minerals on NOx emission from coal combustion

    SciTech Connect

    Yao, M.Y.; Che, D.F.

    2007-07-01

    The catalytic effects of inherent mineral matters on NOx emissions from coal combustion have been investigated by a thermo-gravimetric analyzer (TGA) equipped with a gas analyzer. The effect of demineralization and the individual effect of Na, K, Ca, Mg, and Fe on the formation of NOx are studied as well as the combined catalytic effects of Ca + Na and Ca + Ti. Demineralization causes more Fuel-N to retain in the char, and reduction of NOx mostly. But the mechanistic effect on NOx formation varies from coal to coal. Ca and Mg promote NOx emission. Na, K, Fe suppress NOx formation to different extents. The effect of transition element Fe is the most obvious. The combination of Ca + Na and Ca + Ti can realize the simultaneous control of sulfur dioxide and nitrogen oxides emissions.

  2. Overlapping of heterogeneous and purely thermally activated solid-state processes in the combustion of a bituminous coal

    SciTech Connect

    Senneca, Osvalda; Salatino, Piero

    2006-02-01

    Mechanistic studies of coal combustion have long highlighted the variety of reaction pathways along which gasification may take place. These involve chemisorption of reactants, formation of surface oxides, surface mobility of chemisorbed species, and product desorption. At the same time, exposure of the solid fuel to high temperatures is associated with solid-state thermally activated processes. Altogether, the course of gasification may be profoundly affected by the overlapping and interplay of heterogeneous oxidation with purely thermally activated solid-state reactions. In the present work the combustion of a South African bituminous coal is analyzed in the framework of a simplified reaction network that embodies heterogeneous oxidative and thermally activated processes (pyrolysis, thermal annealing, coal combustion, char combustion, oxygen chemisorption) active both on the raw coal and on its char. The kinetics of each process of the network is assessed by a combination of thermogravimetric and gas analysis on coal and char samples. The analysis is directed to the determination of the prevailing combustion pathway, established from the interplay of oxidative and solid-state thermally activated processes, as a function of combustion conditions (temperature, heating rate, particle size). (author)

  3. Influence of carbon structure and mineral association of coals on their combustion characteristics for pulverized coal injection (PCI) application

    SciTech Connect

    Gupta, S.; Al-Omari, Y.; Sahajwalla, V.; French, D.

    2006-06-15

    The influence of carbon structure and mineral matter of three pulverized coals on their char characteristics including reactivity was studied under a range of combustion conditions in a drop tube furnace (DTF) and thermogravimetric (TGA) furnace for PCI application. Physical and chemical properties of coals and their combustion derivatives were characterized by automated reflectogram. X-ray diffraction, scanning electron microscope, and BET N{sub 2} adsorption. The QEMSCAN{asterisk} technique was used to characterize the heterogeneous nature of minerals of discrete coal particles. The TGA char reactivity was related to the proportion of coal particles displaying strong association of calcium/sulfur phases with carbon matrix to highlight the catalytic influence of minerals on char reactivity at low temperatures. The study suggested that during DTF combustion tests at 1200{sup o}C, char reaction rates might have been catalyzed by coal minerals, particularly due to illite and its association with carbon. Under the same combustion conditions, most of the coal minerals did not transform significantly to slag phases. Coal burnout was found to improve significantly in a combustion temperature range of 1200 to 1500{sup o}C. The improvement of coal burnout with temperature appeared to be influenced by coal properties, particularly as a function of the chemical nature of minerals, as well as the degree of associations with other minerals. The study implies that coals with similar mineral compositions might not necessarily reflect similar combustion behavior due to the differences in their associations with other phases.

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

    SciTech Connect

    Helble, J.J.; Srinivasachar, S.; Wilemski, G.; Boni, A.A.; Kang, Shin-Gyoo; Sarofim, A.F.; Graham, K.A.; Beer, J.M.; Peterson, T.W.; Wendt, J.O.L.; Gallagher, N.B.; Bool, L.; Huggins, F.E.; Huffman, G.P.; Shah, N.; Shah, A.

    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.

  5. Char particle fragmentation and its effect on unburned carbon during pulverized coal combustion. Quarterly report, April 1--June 30, 1995

    SciTech Connect

    Mitchell, R.E.

    1996-08-13

    This document is the eleventh quarterly status report of work on a project concerned with the fragmentation of char particles during pulverized coal combustion that was conducted at the High Temperature Gasdynamics Laboratory at Stanford University, Stanford, California. The project is intended to satisfy, in part, PETC`s research efforts to understand the chemical and physical processes that govern coal combustion. The work is pertinent to the char oxidation phase of coal combustion and focuses on how the fragmentation of coal char particles affects overall mass loss rates and how char fragmentation phenomena influence coal conversion efficiency. The knowledge and information obtained allows the development of engineering models that can be used to predict accurately char particle temperatures and total mass loss rates during pulverized coal combustion. In particular, the work provides insight into causes of unburned carbon in the ash of coal-fired utility boilers and furnaces. The overall objectives of the project are: (i) to characterize fragmentation events as a function of combustion environment, (ii) to characterize fragmentation with respect to particle porosity and mineral loadings, (iii) to assess overall mass loss rates with respect to particle fragmentation, and (iv) to quantify the impact of fragmentation on unburned carbon in ash. The knowledge obtained during the course of this project will be used to predict accurately the overall mass loss rates of coals based on the mineral content and porosity of their chars. The work will provide a means of assessing reasons for unburned carbon in the ash of coal fired boilers and furnaces.

  6. MUNICIPAL WASTE COMBUSTION ASSESSMENT: FLUIDIZED BED COMBUSTION

    EPA Science Inventory

    The report documents the results of an assessment of fluidized bed combustors (FBCs) to minimize air emissions from municipal waste combustors (MWCs). Objectives of the assessment were to identify the population of existing and planned refuse fired FBC facilities in the U.S., exa...

  7. Environmental assessment of trace elements from coal combustion in the semi-arid west. Progress summary report for FY 1976-1979

    SciTech Connect

    Wangen, L.E.; Dreesen, D.R.

    1981-02-01

    The results of research during FY 1976, FY 1976A, FY 1977, and FY 1979 under terms of the Interagency Energy/Environment Agreement are summarized. Trace element studies have been centered around the coal-fired Four Corners Power Plant located on the Navajo Reservation in northwestern New Mexico, which forms an integral part of the energy-rich Colorado Plateau region. The overall objective of this research has been to assess environmental consequences of trace elements identified as potentially hazardous to arid western ecosystems. To this end the two major corollary goals are to: (1) identify potentially hazardous trace elements in stack emissions and assess their importance with respect to deposition onto surrounding terrain, and (2) to determine which elements are mobilized in the scrubber system and ash disposal ponds at the Four Corners Power Plant. Results of dry deposition calculations, trace element measurements in air particulate, soils, and vegetation are reported pursuant to the first goal. Trace elements extracted from fly ash, trace element measurements in influent and effluent waters of the power plant, and trace element concentrations in a specie of vegetation growing in these effluent water channels are reported pursuant to the second goal.

  8. ON TRIMODAL PARTICLE SIZE DISTRIBUTIONS IN FLY ASH FROM PULVERIZED COAL COMBUSTION

    EPA Science Inventory

    Combustion generated fine particles, defined as those with aerodynamic diameters less than 2.5 micrometers, have come under increased regulatory scrutiny because of suspected links to adverse human health effects. Whereas classical theories regarding coal combustion suggest that ...

  9. LES Modeling of Oxy-combustion of Pulverized Coal: Preliminary Study

    NASA Astrophysics Data System (ADS)

    Warzecha, Piotr; Boguslawski, Andrzej

    2009-12-01

    The paper presents preliminary results of pulverized coal combustion process modeling using Large Eddy Simulation. First the methodology for the testing of mesh resolution is presented. The combustion process was carried out using equilibrium model with single mixture fraction approach.

  10. Coal slurry combustion optimization on single cylinder engine

    SciTech Connect

    Not Available

    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.

  11. Preparation and combustion of high ash coal tailing slurry

    SciTech Connect

    Zhang Ziping; Zhang Wenfu; Fu Xiaoheng; Wang Zuna; Li Hui

    1998-12-31

    Flotation tailings from a coal preparation plant are known for their high ash, low heating value, high moisture content even after thickening and filtration, and difficult handability. However, they can be easily converted into a slurry fuel for boilers. Two flotation tailings, containing ash of 31.89% and 41.87% respectively, have been converted into slurry fuel with the following properties: solid content being 70.4% and 74.4% respectively; low heating value, 13,694kj/kg and 10,970kj/kg; and viscosity, 379 mPa.s and 180 mPa.s at a shear rate of 100s{sup {minus}1}. An eccentric slant jet coal slurry burner was installed at the boiler. Slurry atomizing nozzle operated at low pressure. Both slurries gave stable combustion without supporting fuel under the condition of cool air supply. A new way of flotation tailing utilization was demonstrated. China has more than 200 coal preparation plants washing more than 300 million tons of coal annually. These preparation plants generate more than 10 million tons of tailing annually, most of which is not currently being used, causing great environmental pollution and waste management difficulties for the enterprises. Comprehensive utilization of coal washer tailings is one of the key issues of environmental protection and energy saving in China.

  12. WASTE AND WATER MANAGEMENT FOR CONVENTIONAL COAL COMBUSTION ASSESSMENT REPORT-1979. VOLUME III. GENERATION AND CHARACTERIZATION OF FGC (FLUE GAS CLEANING) WASTES

    EPA Science Inventory

    The report, the third of five volumes, focuses on trends in generation of coal ash and FGD wastes (together comprising FGC wastes) and the characteristics of these wastes. With increasing use of coal, the generation of FGC wastes is expected to increased dramatically: to about 11...

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

    PubMed

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

    2016-06-01

    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. PMID:26897573

  14. CONTROL OF TRACE METAL EMISSIONS DURING COAL COMBUSTION

    SciTech Connect

    THOMAS C. HO

    1998-02-18

    Emissions of toxic trace metals in the form of metal fumes or submicron particulates from a coal-fired combustion source have received greater environmental and regulatory concern over the past years. Current practice of controlling these emissions is to collect them at the cold-end of the process by air-pollution control devices (APCDs) such as electrostatic precipitators and baghouses. However, trace metal fumes may not always be effectively collected by these devices because the formed fumes are extremely small. The proposed research is to explore the opportunities for improved control of toxic trace metal emissions, alternatively, at the hot-end of the coal combustion process, i.e., in the combustion chamber. The technology proposed is to prevent the metal fumes from forming during the process, which would effectively eliminate the metal emission problems. Specifically, the technology is to employ suitable sorbents to (1) reduce the amount of metal volatilization during combustion and (2) capture volatilized metal vapors. The objectives of the project are to demonstrate the technology and to characterize the metal capture process during coal combustion in a fluidized bed combustor. This final technical report details the work performed, the conclusions obtained, and the accomplishments achieved over the project performance period from July 1, 1994 through December 31, 1997. Specifically, this report consists of the following five chapters: Chapter 1. Executive Summary; Chapter 2. Metal Capture by Various Sorbents; Chapter 3. Simultaneous Metal and Sulfur Capture; Chapter 4. Sorption and Desorption of Mercury on Sorbents; and Chapter 5. Project Conclusions. In summary, the metals involved in the project were arsenic, cadmium, chromium, lead, mercury and selenium and the sorbents tested included bauxite, zeolite and calcined limestone. The three sorbents have been found to have various degree of metal capture capability on arsenic, cadmium, chromium and lead

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

    SciTech Connect

    Adams, Bradley; Davis, Kevin; Senior, Constance; Shim, Hong Shim; Otten, Brydger; Fry, Andrew; Wendt, Jost; Eddings, Eric; Paschedag, Alan; Shaddix, Christopher; Cox, William; Tree, Dale

    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.

  16. Method for reducing NOx during combustion of coal in a burner

    DOEpatents

    Zhou, Bing; Parasher, Sukesh; Hare, Jeffrey J.; Harding, N. Stanley; Black, Stephanie E.; Johnson, Kenneth R.

    2008-04-15

    An organically complexed nanocatalyst composition is applied to or mixed with coal prior to or upon introducing the coal into a coal burner in order to catalyze the removal of coal nitrogen from the coal and its conversion into nitrogen gas prior to combustion of the coal. This process leads to reduced NOx production during coal combustion. The nanocatalyst compositions include a nanoparticle catalyst that is made using a dispersing agent that can bond with the catalyst atoms. The dispersing agent forms stable, dispersed, nano-sized catalyst particles. The catalyst composition can be formed as a stable suspension to facilitate storage, transportation and application of the catalyst nanoparticles to a coal material. The catalyst composition can be applied before or after pulverizing the coal material or it may be injected directly into the coal burner together with pulverized coal.

  17. Healy Clean Coal Project: A DOE Assessment

    SciTech Connect

    National Energy Technology Laboratory

    2003-09-01

    The goal of the U.S. Department of Energy's (DOE) Clean Coal Technology (CCT) Program is to provide the energy marketplace with advanced, more efficient, and environmentally responsible coal utilization options by conducting demonstrations of new technologies. These demonstration projects are intended to establish the commercial feasibility of promising advanced coal technologies that have been developed to a level at which they are ready for demonstration testing under commercial conditions. This document serves as a DOE post-project assessment (PPA) of the Healy Clean Coal Project (HCCP), selected under Round III of the CCT Program, and described in a Report to Congress (U.S. Department of Energy, 1991). The desire to demonstrate an innovative power plant that integrates an advanced slagging combustor, a heat recovery system, and both high- and low-temperature emissions control processes prompted the Alaska Industrial Development and Export Authority (AIDEA) to submit a proposal for this project. In April 1991, AIDEA entered into a cooperative agreement with DOE to conduct this project. Other team members included Golden Valley Electric Association (GVEA), host and operator; Usibelli Coal Mine, Inc., coal supplier; TRW, Inc., Space & Technology Division, combustor technology provider; Stone & Webster Engineering Corp. (S&W), engineer; Babcock & Wilcox Company (which acquired the assets of Joy Environmental Technologies, Inc.), supplier of the spray dryer absorber technology; and Steigers Corporation, provider of environmental and permitting support. Foster Wheeler Energy Corporation supplied the boiler. GVEA provided oversight of the design and provided operators during demonstration testing. The project was sited adjacent to GVEA's Healy Unit No. 1 in Healy, Alaska. The objective of this CCT project was to demonstrate the ability of the TRW Clean Coal Combustion System to operate on a blend of run-of-mine (ROM) coal and waste coal, while meeting strict

  18. Natural attenuation of coal combustion waste in river sediments.

    PubMed

    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. PMID:24756414

  19. Combustion of volatile matter during the initial stages of coal combustion

    SciTech Connect

    Marlow, D.; Niksa, S.; Kruger, C.H.

    1990-08-01

    Both the secondary pyrolysis and combustion of the volatiles from a bituminous coal will be studied. Devolatilization and secondary pyrolysis experiments will be conducted in a novel flow reactor in which secondary pyrolysis of the volatiles occurs after devolatilization is complete. This allows unambiguous measurements of the yields from both processes. Measurements will be made for reactor temperatures from 1500 to 1700 K, and a nominal residence time of 200 msec. These conditions are typical of coal combustion. Yields of tar, soot, H{sub 2}, CO, CH{sub 4}, and C{sub 2} and C{sub 3} hydrocarbons will be determined as a function of reactor temperature. The yields will be reported as a function of the temperature of the reactor. The instrumentation for temperature measurements will be developed during future studies. Combustion studies will be conducted in a constant volume bomb, which will be designed and constructed for this study. Tar and soot will be removed before introducing the volatiles to the bomb, so that only the combustion of the light gas volatiles will be considered. The burning velocities of light gas volatiles will be determined both as functions of mixture stoichiometry and the temperature at which the volatiles are pyrolysed. 90 refs., 70 figs., 13 tabs.

  20. Modeling of pulverized coal combustion in cement rotary kiln

    SciTech Connect

    Shijie Wang; Jidong Lu; Weijie Li; Jie Li; Zhijuan Hu

    2006-12-15

    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 rotary kiln were obtained by numerical simulation of a 3000 t/d rotary kiln with a four-channel burner. The predicted results indicated that the improved model accounts for the thermal enthalpy of the clinker formation process and can give more insight (such as fluid flow, temperature, etc,) from within the cement rotary kiln, which is a benefit to better understanding of combustion behavior and an improvement of burner and rotary kiln technology. 25 refs., 12 figs., 5 tabs.

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

    PubMed

    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. PMID:26488499

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

    SciTech Connect

    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.

  3. Release of mercury vapor from coal combustion ash.

    PubMed

    Heebink, Loreal V; Hassett, David J

    2002-08-01

    The long-term stability of Hg in coal combustion by-products (CCBs) was evaluated at ambient and near-ambient temperatures. Six CCB samples with atypically high levels of total Hg were selected for study assuming a greater potential for release of measurable amounts of Hg vapor. The samples selected included two fly ash samples from U.S. eastern bituminous coal, two fly ash samples from South African low-rank coal, one fly ash from Powder River Basin (PRB) subbituminous coal blended with petroleum coke, and one PRB subbituminous coal fly ash incorporated with flue gas desulfurization material. Air scrubbed of Hg was passed through compacted 100-g aliquots of each sample at 1 mL/min and vented to a gold-coated quartz trap to collect released Hg vapor. The samples were maintained at ambient and near-ambient (37 degrees C) temperatures. All samples released low-picogram levels of Hg after 90 days. No pattern was evident to link the total Hg content to the rate of release of Hg vapor. An average of 0.030 pg Hg/g CCB/day was released from the samples, which equates to 2.2 x 10(-8) lb Hg/ton CCB/year. If this were applied to a coal-fired power plant production of 200,000 tons of fly ash per year, there would be a maximum potential release of 0.0044 lb, or 2.00 g, of Hg per year. Experiments are continuing to determine long-term vapor release of Hg from CCBs. All samples have been set up in duplicate at ambient temperature with an improved apparatus to reevaluate results reported in this article. PMID:12184691

  4. Transformations of inorganic coal constituents in combustion systems

    SciTech Connect

    Helble, J.J.; Srinivasachar, S.; Wilemski, G.; Boni, A.A. ); Kang, Shim-Gyoo; Sarofim, A.F.; Graham, K.A.; Beer, J.M. ); Peterson, T.W.; Wendt, O.L.; Gallagher, N.B.; Bool, L. ); 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.

  5. Economic realities of coal combustion by-product utilization

    SciTech Connect

    Colmar, J.A.

    1997-09-01

    The purpose of this paper is to highlight the economic issues associated with coal combustion by-product (CCB) utilization and to discuss both technical and cost considerations of commercialization. Handling, processing, and distribution aspects as well as geographic location and competing materials will affect utilization. Several case studies including fly ash in rick, FGD gypsum vs. mined gypsum, and bottom ash vs. lightweight aggregate are presented detailing these issues. Understanding these factors will provide insight to evaluating barriers for CCB utilization which is the first step toward high volume CCB utilization.

  6. CaO interaction in the staged combustion of coal

    SciTech Connect

    Levy, A.; Merryman, E.L.; Rising, B.W.

    1983-12-19

    The LIMB (limestone injection multi-stage burner) process offers special potential for reducing NO/sub x/ and SO/sub x/ by at least 50 percent in coal combustion. This is to be accomplished by adding limestone with fuel and/or air in a low NO/sub x/ burner. This program has been directed to defining the chemistry and kinetics necessary to optimize sulfur capture in LIMB combustion. More specifically, this program has attempted to clarify the role of calcium sulfide in LIMB chemistry. When limestone is added in a staged burner, there is a strong possibility that under certain circumstances CaS is produced in the reducing (fuel-rich) zone of the burner. Since CaS is more stable than CaSO/sub 4/, this affords the opportunity to (1) operate the burner at a higher temperature, 2200 to 2500 F, (2) pass the CaS rapidly through the high temperature zone (before dissociation), and (3) complete the combustion in a lean (air-rich) region where the sulfur is finally retained in CaSO/sub 4/. For these reasons this program has concentrated on the high temperature chemistry and kinetics of CaS. To achieve the program objective, the program was divided into three tasks. These involved (1) a study of CaS formation, (2) a brief examination of CaS oxidation, and (3) a laboratory examination of the combustion of coal in the presence of CaO under first stage, fuel-rich conditions. In the most general sense, the study has shown that the formation of CaS in the reducing zones of the burner may be restricted by competing kinetics and thermodynamics. The addition of lime in LIMB will require special care to optimize the ability to capture sulfur. 36 references, 44 figures, 10 tables.

  7. Navajo Coal Combustion and Respiratory Health Near Shiprock, New Mexico

    PubMed Central

    Bunnell, Joseph E.; Garcia, Linda V.; Furst, Jill M.; Lerch, Harry; Olea, Ricardo A.; Suitt, Stephen E.; Kolker, Allan

    2010-01-01

    Indoor air pollution has been identified as a major risk factor for acute and chronic respiratory diseases throughout the world. In the sovereign Navajo Nation, an American Indian reservation located in the Four Corners area of the USA, people burn coal in their homes for heat. To explore whether/how indoor coal combustion might contribute to poor respiratory health of residents, this study examined respiratory health data, identified household risk factors such as fuel and stove type and use, analyzed samples of locally used coal, and measured and characterized fine particulate airborne matter inside selected homes. In twenty-five percent of homes surveyed coal was burned in stoves not designed for that fuel, and indoor air quality was frequently found to be of a level to raise concerns. The average winter 24-hour PM2.5 concentration in 20 homes was 36.0 μg/m3. This is the first time that PM2.5 has been quantified and characterized inside Navajo reservation residents' homes. PMID:20671946

  8. Navajo Coal Combustion and Respiratory Health Near Shiprock, New Mexico

    DOE PAGESBeta

    Bunnell, Joseph E.; Garcia, Linda V.; Furst, Jill M.; Lerch, Harry; Olea, Ricardo A.; Suitt, Stephen E.; Kolker, Allan

    2010-01-01

    Indoormore » air pollution has been identified as a major risk factor for acute and chronic respiratory diseases throughout the world. In the sovereign Navajo Nation, an American Indian reservation located in the Four Corners area of the USA, people burn coal in their homes for heat. To explore whether/how indoor coal combustion might contribute to poor respiratory health of residents, this study examined respiratory health data, identified household risk factors such as fuel and stove type and use, analyzed samples of locally used coal, and measured and characterized fine particulate airborne matter inside selected homes. In twenty-five percent of homes surveyed coal was burned in stoves not designed for that fuel, and indoor air quality was frequently found to be of a level to raise concerns. The average winter 24-hour PM 2.5 concentration in 20 homes was 36.0  μ g/ m 3 . This is the first time that PM 2.5 has been quantified and characterized inside Navajo reservation residents' homes.« less

  9. Catalytic Unmixed Combustion of Coal with Zero Pollution

    SciTech Connect

    George Rizeq; Parag Kulkarni; Raul Subia; Wei Wei

    2005-12-01

    GE Global Research is developing an innovative energy-based technology for coal combustion with high efficiency and near-zero pollution. This Unmixed Combustion of coal (UMC-Coal) technology simultaneously converts coal, steam and air into two separate streams of high pressure CO{sub 2}-rich gas for sequestration, and high-temperature, high-pressure vitiated air for producing electricity in gas turbine expanders. The UMC process utilizes an oxygen transfer material (OTM) and eliminates the need for an air separation unit (ASU) and a CO{sub 2} separation unit as compared to conventional gasification based processes. This is the final report for the two-year DOE-funded program (DE-FC26-03NT41842) on this technology that ended in September 30, 2005. The UMC technology development program encompassed lab- and pilot-scale studies to demonstrate the UMC concept. The chemical feasibility of the individual UMC steps was established via lab-scale testing. A pilot plant, designed in a related DOE funded program (DE-FC26-00FT40974), was reconstructed and operated to demonstrate the chemistry of UMC process in a pilot-scale system. The risks associated with this promising technology including cost, lifetime and durability OTM and the impact of contaminants on turbine performance are currently being addressed in detail in a related ongoing DOE funded program (DE-FC26-00FT40974, Phase II). Results obtained to date suggest that this technology has the potential to economically meet future efficiency and environmental performance goals.

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

    SciTech Connect

    Hardesty, D.R.; 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.

  11. Combustion characterization of the blend of plant coal and recovered coal fines. Technical report, December 1, 1991--February 29, 1992

    SciTech Connect

    Singh, S.; Scaroni, A.; Miller, B.; Choudhry, V.

    1992-08-01

    The overall objective of this proposed research program is to determine the combustion characteristics of the blend derived from mixing a plant coal and recovered and clean coal fines from the pond. During this study, one plant coal and three blend samples will be prepared and utilized. The blend samples will be of a mixture of 90% plant coal + 10% fines, 85% plant coal + 15% fines, 80% plant coal + 20% fines having particle size distribution of 70% passing through -200 mesh size. These samples` combustion behavior will be examined in two different furnaces at Penn State University, i.e., a down-fired furnace and a drop-tube furnace. The down-fired furnace will be used mainly to measure the emissions and ash deposition study, while the drop tube furnace will be used to determine burning profile, combustion efficiency, etc.

  12. CONVENTIONAL COMBUSTION ENVIRONMENTAL ASSESSMENT PROGRAM, EXECUTIVE BRIEFING

    EPA Science Inventory

    The brochure gives an executive briefing of EPA's Conventional Combustion Environmental Assessment (CCEA) Program. The CCEA Program was established recently to coordinate and integrate EPA's research and development efforts for assessing the environmental effects of pollutants fr...

  13. STRUCTURE-BASED PREDICTIVE MODEL FOR COAL CHAR COMBUSTION

    SciTech Connect

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

    1998-09-11

    for Premium Carbon Products from Coal. Possibilities for interactions with this new center will be explored. Also this period, an invited review paper was prepared for the 27th International Symposium on Combustion, to be held in Boulder, Colorado in August. The paper is entitled; "Structure, Properties, and Reactivity of Solid Fuels," and reports on a number of advances made in this collaborative project.

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

    NASA Astrophysics Data System (ADS)

    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.

  15. Burning of suspended coal-water slurry droplet with oil as combustion additive. Final report

    SciTech Connect

    Yao, S.C.

    1984-10-01

    The combustion of single coal-water slurry droplet with oil as combustion additive (CWOM) has been studied. In this study, the droplet is suspended on a fine quartz fiber and is exposed to the hot combustion product of propane (C/sub 3/H/sub 8/) and air. The results are documented in a movie series. The combustion of CWOM with various combinations of concentrations are compared with that of coal-water slurry and water-oil mixture droplets. The combustion of coal-water slurry is enhanced significantly due to the presence of emulsified kerosene. The enhancement is also dependent upon the mixing procedure during preparation of CWOM. The presence of emulsified kerosene induces local boil-off and combustion that coal particles are splashed as fire works during the early evaporation stage of droplet heat-up. After particle splashing, blow-holes appear on the droplet surface. The popcorn and swelling phenomena usually occurred in coal-water-slurry combustion is greatly reduced. Significant combustion enhancement occurs with the use of kerosene in an amount of about 15 percent of the overall CWOM. This process of using kerosene as combustion additive may provide obvious advantage for the combustion of bituminous coal-water slurry. 4 references, 6 figures.

  16. Co-combustion of sludge with coal or wood

    SciTech Connect

    Leckner, B.; Aamand, L.-E.

    2004-07-01

    There are several options for co-combustion of biomass or waste with coal. In all cases the fuel properties are decisive for the success of the arrangement: contents of volatile matter and of potential emission precursors, such as sulphur, nitrogen, chlorine, and heavy metals. The content of alkali in the mineral substance of the fuel is important because of the danger of fouling and corrosion. Research activities at Chalmers University of Technology include several aspects of the related problems areas. An example is given concerning emissions from co-combustion in circulating fluidized beds with coal or wood as base fuels, and with sewage sludge as additional fuel. Two aspects of the properties of sludge are studied: emissions of nitrogen and sulphur oxides as well as of chlorine, because the contents of the precursors to these emissions are high. The possibility of utilizing the phosphorus in sludge as a fertilizer is also discussed. The results show that emissions can be kept below existing emission limits if the fraction of sludge is sufficiently small but the concentration of trace elements in the sludge ash prevents the sludge from being used as a fertilizer. 15 refs., 9 figs., 2 tabs.

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

    SciTech Connect

    Hurt, R.; Colo, J; Essenhigh, R.; Hadad, C; Stanley, E.

    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.

  18. Combustion and fuel characterization of coal-water fuels

    SciTech Connect

    Beal, H.R.; Gralton, G.W.; Gronauer, T.W.; Liljedahl, G.N.; Love, B.F.

    1987-06-01

    Activities conducted under this contract include studies on the combustion and fireside behavior of numerous coal-water fuels (CWFs). The work has been broken down into the following areas: Task 1 -- Selection of Candidate Fuels; Task 2 -- Bench Scale Tests; Task 3 -- CWF Preparation and Supply; Task 4 -- Combustion Characterization; Task 5 -- Ash Deposition and Performance Testing; Task 6 -- Commercial Applications. This report covers Task 6, the study of commercial applications of CWFs as related to the technical and economic aspects of the conversion of existing boilers and heaters to CWF firing. This work involves the analysis of seven units of various sizes and configurations firing several selected CWFs. Three utility boilers, two industrial boilers, and two process heater designs are included. Each of the units was considered with four primary selected CWFs. A fifth fuel was considered for one of the utility units. A sixth fuel, a microfine grind CWF, was evaluated on two utility units and one industrial unit. The particular fuels were chosen with the objective of examining the effects of coal source, ash level, ash properties, and beneficiation on the CWF performance and economics of the seven units. 10 refs., 81 figs., 80 tabs.

  19. Possible criteria for establishing the quality and efficiency of coal combustion

    SciTech Connect

    Repic, B.S.; Jovanovic, M.P.; Saijnikov, A.V.

    1998-07-01

    Experimental results of pulverized coal combustion and possible criteria for establishing its quality and efficiency are presented in the paper. Experimental investigations of combustion of several types of coals (lignite, sub-bituminous, bituminous) were conducted at the experimental facility using movable blocks swirl burner. For estimation of quality and efficiency of coal combustion, apart from subjective evaluation and measurements in flame, two criteria were used, reactivity index (inverse of fuel number) and so-called pore resistance number. Rankings of investigated coals, based both on experimental results and the values of mentioned criteria, show quite good agreement and point out the possibility of wider use of these criteria.

  20. Ash transformations in the real-scale pulverized coal combustion of South African and Colombian coals

    SciTech Connect

    Lind, T.; Kauppinen, E.I.; Valmari, T.; Klippel, N.; Mauritzson, C.

    1996-12-31

    In this work, the formation of ash particles in the combustion of South African Klein Kropie coal and a Colombian coal was studied by measuring the ash particle characteristics upstream of the electrostatic precipitator (ESP) at a 510 MW{sub e} pulverized coal fired power plant. The authors measured the ash particle mass size distributions in the size range 0.01--50 {micro}m using low-pressure impactors and precutter cyclones. Also, samples were collected for computer controlled scanning electron microscopy (CCSEM) with a cyclone with an aerodynamic cut-diameter of about 1 {micro}m. The cyclone-collected samples were analyzed with standard CCSEM procedure by depositing the particles on a filter, and by embedding the particles in epoxy hence acquiring the cross-section analysis of the sample. All major mineral classes in both coals were found to undergo extensive coalescence during combustion. Iron, calcium and magnesium rich particles resulting from the decomposition of pyrite, calcite and dolomite were found to coalesce with quartz and aluminosilicate particles. The size distributions of the fly ash determined with CCSEM and low-pressure impactor-cyclone sampler were found to be similar.

  1. Toxic airborne S, PAH, and trace element legacy of the superhigh-organic-sulphur Raša coal combustion: Cytotoxicity and genotoxicity assessment of soil and ash.

    PubMed

    Medunić, Gordana; Ahel, Marijan; Mihalić, Iva Božičević; Srček, Višnja Gaurina; Kopjar, Nevenka; Fiket, Željka; Bituh, Tomislav; Mikac, Iva

    2016-10-01

    This paper presents the levels of sulphur, polycyclic aromatic hydrocarbons (PAHs), and potentially toxic trace elements in soils surrounding the Plomin coal-fired power plant (Croatia). It used domestic superhigh-organic-sulphur Raša coal from 1970 until 2000. Raša coal was characterised by exceptionally high values of S, up to 14%, making the downwind southwest (SW) area surrounding the power plant a significant hotspot. The analytical results show that the SW soil locations are severely polluted with S (up to 4%), and PAHs (up to 13,535ng/g), while moderately with Se (up to 6.8mg/kg), and Cd (up to 4.7mg/kg). The composition and distribution pattern of PAHs in the polluted soils indicate that their main source could be airborne unburnt coal particles. The atmospheric dispersion processes of SO2 and ash particles have influenced the composition and distribution patterns of sulphur and potentially toxic trace elements in studied soils, respectively. A possible adverse impact of analysed soil on the local karstic environment was evaluated by cytotoxic and genotoxic methods. The cytotoxicity effects of soil and ash water extracts on the channel catfish ovary (CCO) cell line were found to be statistically significant in the case of the most polluted soil and ash samples. However, the primary DNA-damaging potential of the most polluted soil samples on the CCO cells was found to be within acceptable boundaries. PMID:27232961

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

    PubMed

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

    2014-11-01

    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. PMID:25459855

  3. The effect of upgrading processes on combustion characteristics of Berau coal

    SciTech Connect

    Datin Fatia Umar; Binarko Santoso; Hiromoto Usui

    2007-12-15

    Indonesian coal was upgraded by upgraded brown coal (UBC), hot water drying (HWD), and steam drying (SD) processes to study the combustion characteristics of this coal. The differential thermal-thermogravimetric analysis (DTA-TG) was carried out to obtain some combustion parameters, such as, ignition temperature (T{sub ig}), maximum combustion rate temperature (T{sub max}), maximum combustion rate (R{sub max}), char burn-out temperature (T{sub bo}), and ash yield. The differential thermal analyzer (DTA) curve can be used to estimate the heat released during the combustion process, which corresponds to the high heating value of the coal. The results show that the combustion characteristics of HWD and SD processes are much better than those of the UBC process. This is because the UBC process was conducted at lower temperature and pressure. 11 refs., 2 figs., 3 tabs.

  4. Char particle fragmentation and its effects on unburned carbon during pulverized coal combustion. Quarterly report, January 1, 1995--March 31, 1995

    SciTech Connect

    Mitchell, R.E.

    1995-08-01

    This document is the tenth quarterly status report of work on a project concerned with the fragmentation of char particles during pulverized coal combustion that is being conducted at the High Temperature Gasdynamics Laboratory at Stanford University. The project is intended to satisfy, in part, PETC`s research efforts to understand the chemical and physical processes that govern coal combustion. The work is pertinent to the char oxidation phase of coal combustion and focuses on how the fragmentation of coal char particles affects overall mass loss rates and how char fragmentation phenomena influence coal conversion efficiency. The knowledge and information obtained will allow the development of engineering models that can be used to predict accurately char particle temperatures and total mass loss rates during pulverized coal combustion. The overall objectives of the project are: (1) to characterize fragmentation events as a function of combustion environment, (2) to characterize fragmentation with respect to particle porosity and mineral loadings, (3) to assess overall mass loss rates with respect to particle fragmentation, and (4) to quantify the impact of fragmentation on unburned carbon in ash. The knowledge obtained during the course of this project will be used to predict accurately the overall mass loss rates of coals based on the mineral content and porosity of their chars. The work will provide a means of assessing reasons for unburned carbon in the ash of coal fired boilers and furnaces. Accomplishments for this period are presented for Task 3, char fragmentation studies and Task 4, fragmentation modelling.

  5. Physicochemical characterizations of limestone for fluidized-bed coal combustion

    SciTech Connect

    Fuller, E.L. Jr.; Yoos, T.R. III; Walia, D.S.

    1981-05-01

    This study is an investigation of the physicochemical characteristics of three limestone samples, Quincy limestone (-20 + 60), Franklin limestone (-12 + 30), and Franklin limestone (-6 + 16), currently being tested at Oak Ridge National Laboratory for use in a fluidized-bed coal combustion unit. By correlating the chemistry, mineralogy, and surface area of these samples with empirical data obtained at Argonne National Laboratory, the sulfur capture ability and performance of these limestones can be loosely predicted. X-ray fluorescence and neutron activation analysis revealed a very high calcium content and very low concentrations of other elements in the three samples. X-ray diffraction patterns and petrographic examination of the limestone grains detected essentially no dolomite in the Quincy limestone or the fine Franklin limestone samples. The coarse Franklin limestone sample showed dolomite to be present in varying amounts up to maximum of 2.75%. Limited surface chemistry investigations of the samples were undertaken. Limestone and dolostone resources of the Tennessee Valley Authority region are widespread and abundant, and judged sufficient to meet industrial demand for many years. No problems are anticipated in securing limestone or dolostone supplies for a commercial fluidized-bed combustion plant in the Tennessee Valley Authority region. Transportation facilities and costs for limestone or dolostone will influence the siting of such a commercial fluidized-bed combustion plant. The most promising location in the Tennessee Valley Authority region at this time is Paducah, Kentucky.

  6. STRUCTURE-BASED PREDICTIVE MODEL FOR COAL CHAR COMBUSTION

    SciTech Connect

    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

  7. Transformations of inorganic coal constituents in combustion systems

    SciTech Connect

    Boni, A.A.; Helble, J.J.; Srinivasachar, S.; Wilemski, G. ); Sarofim, A.F.; Beer, J.M. ); Peterson, T.W.; Wendt, J.O.L. ); Huffman, G.P.; Huggins, F.E. )

    1990-11-01

    Objectives of this project are: (1) define the partitioning of inorganic constituents associated with raw coal particles among products (including vapors, aerosols, and residual char/ash particles) formed under conditions representative of pulverized coal flames as a function of the specific (intrinsic and extrinsic) characteristics of the raw coal and the environment in which the transformations occur; and (2) characterize the resultant spectrum of products in detail; elucidate and quantify the fundamental processes by which transformations of the inorganic constituents occur; and develop, based on the information required in a. and b. above, a tractable process'' model capable of predicting the significant features of the transformation process, most importantly, the nature and distribution of products. The work discussed highlights recent accomplishments in modeling synthetic char particle combustion times and temperatures with allowance for oxygen dissociation in the char boundary layer; in developing a continuum model for residual ash information and char fragmentation, permitting a more detailed time-resolved study of ash coalescence within a burning char particle; and in continuing development of the engineering model for ash particle formation. 40 refs., 25 figs., 10 tabs.

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

    SciTech Connect

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

    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.

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

    SciTech Connect

    Tang, S.L.; Feng, X.B.; Qiu, H.R.; Yin, G.X.; Yang, Z.C.

    2007-10-15

    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{sup P}, 813 kg is Hg{sup 2+} and 817 kg is Hg{sup 0}. 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. Mercury speciation and emissions from coal combustion in Guiyang, Southwest China.

    PubMed

    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. PMID:17517388