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William G. Lloyd - One of the best experts on this subject based on the ideXlab platform.

  • TG/FTIR/MS study of organic compounds evolved during the co-firing of coal and Refuse-Derived Fuels
    Fuel Processing Technology, 1999
    Co-Authors: Shobha Purushothama, J Hyatt, Xiaodong Yang, Wei-ping Pan, John T. Riley, William G. Lloyd
    Abstract:

    Complementary thermal analytical techniques were used to analyze gaseous products evolved during the co-firing of coal with Refuse Derived Fuels. The combined thermogravimetric . . . TG rFourier transform infrared FTIR rmass spectrometry MS techniques were employed to study the reaction pathways for the formation of gaseous products during combustion, as well as identify molecular chlorine, HCl, CO, CO , H O and various organic compounds. The discovery 22 of molecular chlorine has led us to look for the possible formation of chlorinated organic compounds in the combustion process. Chlorine and hydrocarbon species are released in the same temperature range and in higher concentrations during fast heating rates compared to relatively slow ones. These results indicate that there may be more opportunities to form chlorinated organic . compounds during the co-firing of coals with Refuse-Derived Fuels RDF at the faster heating rates . that may occur in a fluidized-bed combustor FBC system. q 1999 Elsevier Science B.V. All rights reserved.

  • tg ftir ms study of organic compounds evolved during the co firing of coal and Refuse Derived Fuels
    Fuel Processing Technology, 1999
    Co-Authors: Shobha Purushothama, J Hyatt, Xiaodong Yang, Wei-ping Pan, John T. Riley, William G. Lloyd
    Abstract:

    Complementary thermal analytical techniques were used to analyze gaseous products evolved during the co-firing of coal with Refuse Derived Fuels. The combined thermogravimetric . . . TG rFourier transform infrared FTIR rmass spectrometry MS techniques were employed to study the reaction pathways for the formation of gaseous products during combustion, as well as identify molecular chlorine, HCl, CO, CO , H O and various organic compounds. The discovery 22 of molecular chlorine has led us to look for the possible formation of chlorinated organic compounds in the combustion process. Chlorine and hydrocarbon species are released in the same temperature range and in higher concentrations during fast heating rates compared to relatively slow ones. These results indicate that there may be more opportunities to form chlorinated organic . compounds during the co-firing of coals with Refuse-Derived Fuels RDF at the faster heating rates . that may occur in a fluidized-bed combustor FBC system. q 1999 Elsevier Science B.V. All rights reserved.

  • Co-firing high sulfur coal with Refuse Derived Fuels. Final report
    1997
    Co-Authors: John T. Riley, William G. Lloyd
    Abstract:

    This project was designed to evaluate the combustion performance of and emissions from a fluidized bed combustor during the combustion of mixtures of high sulfur and/or high chlorine coals and municipal solid waste (MSW). The project included four major tasks, which were as follows: (1) Selection, acquisition, and characterization of raw materials for Fuels and the determination of combustion profiles of combination Fuels using thermal analytical techniques; (2) Studies of the mechanisms for the formation of chlorinated organics during the combustion of MSW using a tube furnace; (3) Investigation of the effect of sulfur species on the formation of chlorinated organics; and (4) Examination of the combustion performance of combination Fuels in a laboratory scale fluidized bed combustor. Several kinds of coals and the major combustible components of the MSW, including PVC, newspaper, and cellulose were tested in this project. Coals with a wide range of sulfur and chlorine contents were used. TGA/MS/FTIR analyses were performed on the raw materials and their blends. The possible mechanism for the formation of chlorinated organics during combustion was investigated by conducting a series of experiments in a tube furnace. The effect of sulfur dioxide on the formation of molecular chlorine during combustion processes was examined in this study.

  • co firing high sulfur coal with Refuse Derived Fuels technical progress report number_sign 11
    Other Information: PBD: 31 May 1997, 1997
    Co-Authors: Wei-ping Pan, John T. Riley, William G. Lloyd
    Abstract:

    The objective of this quarter of study was to prepare fuel pellets containing PVC, newspaper and plastics to be co-fired with coal in the AFBC combustor. The Western Kentucky University atmospheric fluidized bed combustion system requires the fuel to fall from a bunker into a lock-hopper, and from there into a mixing box where the fuel is auger-fed under pressure into the bottom of the fluidized bed. The fuel must flow freely out of the bunker and through the lock- hopper for proper feeding into the combustor. In order for the fuel to continuously fall through these units and into the mixing box during combustion, the density of the fuel and the size of the particles must meet certain requirements. The particles must be no larger than 3/8 inches in diameter and must have a density approaching that of coal. Loose materials such as sawdust, shredded paper products and most shredded plastics do not feed properly in the WKU AFBC system. Bridging and blockage of feed chutes result, even with constant vibration of parts of the feed mechanism. It is not possible to run the AFBC system powered solely by these loose materials.

  • Co-firing high-sulfur coals with Refuse-Derived fuel
    Thermochimica Acta, 1996
    Co-Authors: Shobha Purushothama, J Hyatt, Wei-ping Pan, John T. Riley, William G. Lloyd, John Flynn, Phil Gill
    Abstract:

    Abstract The fundamental thermal behavior of five materials (Illinois coal #6, Kentucky coal #9, polyvinyl chloride, cellulose and newspaper) has been investigated using the TGA/FTIR/MS system under different combustion conditions. At a fast heating rate, the decomposition temperatures shift towards higher temperatures and the maximum weight loss rates increase by 3–7 times those at the slow heating rate. The gases evolved from the decomposition have been analyzed kinetically. More organic compounds are identified at the faster heating rate. Also, molecular chlorine is observed in the oxidation of PVC. These two species may lead to the formation of chlorinated organic compounds. The results indicate that the TGA/FTIR/MS system can be used to evaluate the effect on the environment of co-firing high-sulfur coal with Refuse-Derived Fuels.

Yong Chen - One of the best experts on this subject based on the ideXlab platform.

  • Pyrolysis and Combustion of Refuse-Derived Fuels in a Spouting−Moving Bed Reactor
    Energy & Fuels, 2002
    Co-Authors: Zhiqi Wang, Haitao Huang, Yong Chen
    Abstract:

    A reactor with two reaction zones (pyrolyzer and combustor) is developed, which is proposed for the thermal disposal of solid wastes, especially RDFs (Refuse-Derived Fuels). A model RDF was used to evaluate the performance of the reactor. The RDF is continuously fed to the spouting−moving bed pyrolyzer in which the RDF partially combusts to supply heat for pyrolysis of the RDF at low temperature, then the pyrolysis product burns with secondary air at high temperature in the upper combustor. A special connector cascades the two parts to a vertical configuration, where secondary air is introduced. The effect of operating parameters, such as spouting air and auxiliary air, as well as secondary air flow rate on the pyrolyzer temperature, pyrolysis gas composition at different positions, combustor temperature, and emissions of CO and NOx in flue gas, are studied.

  • pyrolysis and combustion of Refuse Derived Fuels in a spouting moving bed reactor
    Energy & Fuels, 2002
    Co-Authors: Zhiqi Wang, Haitao Huang, Yong Chen
    Abstract:

    A reactor with two reaction zones (pyrolyzer and combustor) is developed, which is proposed for the thermal disposal of solid wastes, especially RDFs (Refuse-Derived Fuels). A model RDF was used to evaluate the performance of the reactor. The RDF is continuously fed to the spouting−moving bed pyrolyzer in which the RDF partially combusts to supply heat for pyrolysis of the RDF at low temperature, then the pyrolysis product burns with secondary air at high temperature in the upper combustor. A special connector cascades the two parts to a vertical configuration, where secondary air is introduced. The effect of operating parameters, such as spouting air and auxiliary air, as well as secondary air flow rate on the pyrolyzer temperature, pyrolysis gas composition at different positions, combustor temperature, and emissions of CO and NOx in flue gas, are studied.

Shobha Purushothama - One of the best experts on this subject based on the ideXlab platform.

  • tg ftir ms study of organic compounds evolved during the co firing of coal and Refuse Derived Fuels
    Fuel Processing Technology, 1999
    Co-Authors: Shobha Purushothama, J Hyatt, Xiaodong Yang, Wei-ping Pan, John T. Riley, William G. Lloyd
    Abstract:

    Complementary thermal analytical techniques were used to analyze gaseous products evolved during the co-firing of coal with Refuse Derived Fuels. The combined thermogravimetric . . . TG rFourier transform infrared FTIR rmass spectrometry MS techniques were employed to study the reaction pathways for the formation of gaseous products during combustion, as well as identify molecular chlorine, HCl, CO, CO , H O and various organic compounds. The discovery 22 of molecular chlorine has led us to look for the possible formation of chlorinated organic compounds in the combustion process. Chlorine and hydrocarbon species are released in the same temperature range and in higher concentrations during fast heating rates compared to relatively slow ones. These results indicate that there may be more opportunities to form chlorinated organic . compounds during the co-firing of coals with Refuse-Derived Fuels RDF at the faster heating rates . that may occur in a fluidized-bed combustor FBC system. q 1999 Elsevier Science B.V. All rights reserved.

  • TG/FTIR/MS study of organic compounds evolved during the co-firing of coal and Refuse-Derived Fuels
    Fuel Processing Technology, 1999
    Co-Authors: Shobha Purushothama, J Hyatt, Xiaodong Yang, Wei-ping Pan, John T. Riley, William G. Lloyd
    Abstract:

    Complementary thermal analytical techniques were used to analyze gaseous products evolved during the co-firing of coal with Refuse Derived Fuels. The combined thermogravimetric . . . TG rFourier transform infrared FTIR rmass spectrometry MS techniques were employed to study the reaction pathways for the formation of gaseous products during combustion, as well as identify molecular chlorine, HCl, CO, CO , H O and various organic compounds. The discovery 22 of molecular chlorine has led us to look for the possible formation of chlorinated organic compounds in the combustion process. Chlorine and hydrocarbon species are released in the same temperature range and in higher concentrations during fast heating rates compared to relatively slow ones. These results indicate that there may be more opportunities to form chlorinated organic . compounds during the co-firing of coals with Refuse-Derived Fuels RDF at the faster heating rates . that may occur in a fluidized-bed combustor FBC system. q 1999 Elsevier Science B.V. All rights reserved.

  • TG/MS study of organic compounds evolved during the co-firing of coal and Refuse Derived Fuels
    1996
    Co-Authors: Shobha Purushothama, R. Lu, Xiadong Yang, J Hyatt
    Abstract:

    The Environmental Protection Agency reported that the total municipal solid waste (MSW) produced in the U.S. increased from 179 million tons in 1988 to 195 million tons in 1990. It is predicted that the country will produce about 216 million tons of garbage in the year 2000. Waste-to-energy conversion of MSW appears to be most attractive because of the energy recovered, economic value of the recycled materials, and the cost saving Derived from reduced landfill usage. However, extra care needs to be taken in burning MSW or Refuse Derived Fuel (RDF) to optimize the operating conditions of a combustor so that the combustion takes place in an environmentally acceptable manner. For instance, polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) have been found in the precipitator fly ash and flue gas of a number of incinerator facilities in the United States and Europe. Though the amount of PCDDs and PCDFs is only in the parts-per-billion to parts-per-trillion range, these chlorinated organics exhibit very high toxicity (LD{sub 50} < 10 {mu}g/Kg) and 2,3,7,8-tetrachlorodibenzodioxin has been found to be acnegenic, carcinogenic, and teratogenic. This has slowed or even stopped the construction and operation of waste-to-energy plants. In previous work, the study of singlemore » materials has given us a good understanding of the characteristics and thermal behavior of these materials, their relative thermal stability and temperature relationships, their decomposition products and the evolution profiles of different gaseous products. The formation of molecular chlorine during combustion processes could be a key step for the formation of chlorinated organic compounds. The production of phenol and furan during the combustion of newspaper and cellulose could provide the important precursors for the formation of polychlorinated dibenzodioxin (PCDD) and polychlorinated dibenzofuran (PCDF).« less

  • Co-firing high-sulfur coals with Refuse-Derived fuel
    Thermochimica Acta, 1996
    Co-Authors: Shobha Purushothama, J Hyatt, Wei-ping Pan, John T. Riley, William G. Lloyd, John Flynn, Phil Gill
    Abstract:

    Abstract The fundamental thermal behavior of five materials (Illinois coal #6, Kentucky coal #9, polyvinyl chloride, cellulose and newspaper) has been investigated using the TGA/FTIR/MS system under different combustion conditions. At a fast heating rate, the decomposition temperatures shift towards higher temperatures and the maximum weight loss rates increase by 3–7 times those at the slow heating rate. The gases evolved from the decomposition have been analyzed kinetically. More organic compounds are identified at the faster heating rate. Also, molecular chlorine is observed in the oxidation of PVC. These two species may lead to the formation of chlorinated organic compounds. The results indicate that the TGA/FTIR/MS system can be used to evaluate the effect on the environment of co-firing high-sulfur coal with Refuse-Derived Fuels.

Wei-ping Pan - One of the best experts on this subject based on the ideXlab platform.

  • characterization of ash deposition during co combustion of coal with Refuse Derived Fuels in a pilot fbc facility
    17th International Conference on Fluidized Bed Combustion, 2003
    Co-Authors: Jun Zhang, Wei-ping Pan, Kunlei Liu, John T. Riley
    Abstract:

    This paper presents data from a recent investigation of the character of ash deposition in the convective zone (547°C to 338°C) in a 0.1 MWth bench-scale FBC system at Western Kentucky University. The ash deposit samples were collected during co-firing experiments using two coals with various blends of a Refuse-Derived fuel (RDF). A low sulfur coal, a high sulfur coal, and commercially available RDF sample were selected to investigate the influence of sulfur and chlorine in the Fuels on the formation of ash deposits. Limestone was added to the combustor as the bed material and desulfurization sorbent. The results showed that the formation of ash deposits had a close relationship to the active fine lime particles produced from the limestone. An increase in the concentration of SOx in the flue gas restricts the formation of the ash deposits because of the reaction between SOx and the fine lime particles, which drops the adhesive force of the fine lime particles by reducing the contact area among the particles. With an increase in the content of the RDF in the Fuels, the rate of deposit of ash decreased because of the higher content of chlorine and aluminum, which also decreased the contact area among the particles, leading to a low deposition rate of the fly ash.Copyright © 2003 by ASME

  • TG/FTIR/MS study of organic compounds evolved during the co-firing of coal and Refuse-Derived Fuels
    Fuel Processing Technology, 1999
    Co-Authors: Shobha Purushothama, J Hyatt, Xiaodong Yang, Wei-ping Pan, John T. Riley, William G. Lloyd
    Abstract:

    Complementary thermal analytical techniques were used to analyze gaseous products evolved during the co-firing of coal with Refuse Derived Fuels. The combined thermogravimetric . . . TG rFourier transform infrared FTIR rmass spectrometry MS techniques were employed to study the reaction pathways for the formation of gaseous products during combustion, as well as identify molecular chlorine, HCl, CO, CO , H O and various organic compounds. The discovery 22 of molecular chlorine has led us to look for the possible formation of chlorinated organic compounds in the combustion process. Chlorine and hydrocarbon species are released in the same temperature range and in higher concentrations during fast heating rates compared to relatively slow ones. These results indicate that there may be more opportunities to form chlorinated organic . compounds during the co-firing of coals with Refuse-Derived Fuels RDF at the faster heating rates . that may occur in a fluidized-bed combustor FBC system. q 1999 Elsevier Science B.V. All rights reserved.

  • tg ftir ms study of organic compounds evolved during the co firing of coal and Refuse Derived Fuels
    Fuel Processing Technology, 1999
    Co-Authors: Shobha Purushothama, J Hyatt, Xiaodong Yang, Wei-ping Pan, John T. Riley, William G. Lloyd
    Abstract:

    Complementary thermal analytical techniques were used to analyze gaseous products evolved during the co-firing of coal with Refuse Derived Fuels. The combined thermogravimetric . . . TG rFourier transform infrared FTIR rmass spectrometry MS techniques were employed to study the reaction pathways for the formation of gaseous products during combustion, as well as identify molecular chlorine, HCl, CO, CO , H O and various organic compounds. The discovery 22 of molecular chlorine has led us to look for the possible formation of chlorinated organic compounds in the combustion process. Chlorine and hydrocarbon species are released in the same temperature range and in higher concentrations during fast heating rates compared to relatively slow ones. These results indicate that there may be more opportunities to form chlorinated organic . compounds during the co-firing of coals with Refuse-Derived Fuels RDF at the faster heating rates . that may occur in a fluidized-bed combustor FBC system. q 1999 Elsevier Science B.V. All rights reserved.

  • chlorinated organic compounds evolved during the combustion of blends of Refuse Derived Fuels and coals
    Journal of Thermal Analysis and Calorimetry, 1997
    Co-Authors: Xiadong Yang, Wei-ping Pan, W Tomes, John T. Riley
    Abstract:

    The objective of this study was to examine the possible formation of chlorinated organic compounds during the combustion of blends of Refuse Derived Fuels (RDF) and coal under conditions similar to those of an atmospheric fluidized bed combustion (AFBC) system. A series of experiments were conducted using a TG interfaced to FTIR. Additional experiments using a tube furnace preheated to AFBC operating temperatures were also conducted. The combustion products were cryogenically trapped and analyzed with a GC/MS system. The chlorination of phenols and the condensation reactions of chlorophenols were investigated in this study. A possible mechanism for the formation of chlorinated organic compounds such as dibenzodioxins and dibenzofurans, by chlorination and condensation reactions involving phenols, was proposed.

  • co firing high sulfur coal with Refuse Derived Fuels technical progress report number_sign 11
    Other Information: PBD: 31 May 1997, 1997
    Co-Authors: Wei-ping Pan, John T. Riley, William G. Lloyd
    Abstract:

    The objective of this quarter of study was to prepare fuel pellets containing PVC, newspaper and plastics to be co-fired with coal in the AFBC combustor. The Western Kentucky University atmospheric fluidized bed combustion system requires the fuel to fall from a bunker into a lock-hopper, and from there into a mixing box where the fuel is auger-fed under pressure into the bottom of the fluidized bed. The fuel must flow freely out of the bunker and through the lock- hopper for proper feeding into the combustor. In order for the fuel to continuously fall through these units and into the mixing box during combustion, the density of the fuel and the size of the particles must meet certain requirements. The particles must be no larger than 3/8 inches in diameter and must have a density approaching that of coal. Loose materials such as sawdust, shredded paper products and most shredded plastics do not feed properly in the WKU AFBC system. Bridging and blockage of feed chutes result, even with constant vibration of parts of the feed mechanism. It is not possible to run the AFBC system powered solely by these loose materials.

John T. Riley - One of the best experts on this subject based on the ideXlab platform.

  • characterization of ash deposition during co combustion of coal with Refuse Derived Fuels in a pilot fbc facility
    17th International Conference on Fluidized Bed Combustion, 2003
    Co-Authors: Jun Zhang, Wei-ping Pan, Kunlei Liu, John T. Riley
    Abstract:

    This paper presents data from a recent investigation of the character of ash deposition in the convective zone (547°C to 338°C) in a 0.1 MWth bench-scale FBC system at Western Kentucky University. The ash deposit samples were collected during co-firing experiments using two coals with various blends of a Refuse-Derived fuel (RDF). A low sulfur coal, a high sulfur coal, and commercially available RDF sample were selected to investigate the influence of sulfur and chlorine in the Fuels on the formation of ash deposits. Limestone was added to the combustor as the bed material and desulfurization sorbent. The results showed that the formation of ash deposits had a close relationship to the active fine lime particles produced from the limestone. An increase in the concentration of SOx in the flue gas restricts the formation of the ash deposits because of the reaction between SOx and the fine lime particles, which drops the adhesive force of the fine lime particles by reducing the contact area among the particles. With an increase in the content of the RDF in the Fuels, the rate of deposit of ash decreased because of the higher content of chlorine and aluminum, which also decreased the contact area among the particles, leading to a low deposition rate of the fly ash.Copyright © 2003 by ASME

  • TG/FTIR/MS study of organic compounds evolved during the co-firing of coal and Refuse-Derived Fuels
    Fuel Processing Technology, 1999
    Co-Authors: Shobha Purushothama, J Hyatt, Xiaodong Yang, Wei-ping Pan, John T. Riley, William G. Lloyd
    Abstract:

    Complementary thermal analytical techniques were used to analyze gaseous products evolved during the co-firing of coal with Refuse Derived Fuels. The combined thermogravimetric . . . TG rFourier transform infrared FTIR rmass spectrometry MS techniques were employed to study the reaction pathways for the formation of gaseous products during combustion, as well as identify molecular chlorine, HCl, CO, CO , H O and various organic compounds. The discovery 22 of molecular chlorine has led us to look for the possible formation of chlorinated organic compounds in the combustion process. Chlorine and hydrocarbon species are released in the same temperature range and in higher concentrations during fast heating rates compared to relatively slow ones. These results indicate that there may be more opportunities to form chlorinated organic . compounds during the co-firing of coals with Refuse-Derived Fuels RDF at the faster heating rates . that may occur in a fluidized-bed combustor FBC system. q 1999 Elsevier Science B.V. All rights reserved.

  • tg ftir ms study of organic compounds evolved during the co firing of coal and Refuse Derived Fuels
    Fuel Processing Technology, 1999
    Co-Authors: Shobha Purushothama, J Hyatt, Xiaodong Yang, Wei-ping Pan, John T. Riley, William G. Lloyd
    Abstract:

    Complementary thermal analytical techniques were used to analyze gaseous products evolved during the co-firing of coal with Refuse Derived Fuels. The combined thermogravimetric . . . TG rFourier transform infrared FTIR rmass spectrometry MS techniques were employed to study the reaction pathways for the formation of gaseous products during combustion, as well as identify molecular chlorine, HCl, CO, CO , H O and various organic compounds. The discovery 22 of molecular chlorine has led us to look for the possible formation of chlorinated organic compounds in the combustion process. Chlorine and hydrocarbon species are released in the same temperature range and in higher concentrations during fast heating rates compared to relatively slow ones. These results indicate that there may be more opportunities to form chlorinated organic . compounds during the co-firing of coals with Refuse-Derived Fuels RDF at the faster heating rates . that may occur in a fluidized-bed combustor FBC system. q 1999 Elsevier Science B.V. All rights reserved.

  • Co-firing high sulfur coal with Refuse Derived Fuels. Final report
    1997
    Co-Authors: John T. Riley, William G. Lloyd
    Abstract:

    This project was designed to evaluate the combustion performance of and emissions from a fluidized bed combustor during the combustion of mixtures of high sulfur and/or high chlorine coals and municipal solid waste (MSW). The project included four major tasks, which were as follows: (1) Selection, acquisition, and characterization of raw materials for Fuels and the determination of combustion profiles of combination Fuels using thermal analytical techniques; (2) Studies of the mechanisms for the formation of chlorinated organics during the combustion of MSW using a tube furnace; (3) Investigation of the effect of sulfur species on the formation of chlorinated organics; and (4) Examination of the combustion performance of combination Fuels in a laboratory scale fluidized bed combustor. Several kinds of coals and the major combustible components of the MSW, including PVC, newspaper, and cellulose were tested in this project. Coals with a wide range of sulfur and chlorine contents were used. TGA/MS/FTIR analyses were performed on the raw materials and their blends. The possible mechanism for the formation of chlorinated organics during combustion was investigated by conducting a series of experiments in a tube furnace. The effect of sulfur dioxide on the formation of molecular chlorine during combustion processes was examined in this study.

  • chlorinated organic compounds evolved during the combustion of blends of Refuse Derived Fuels and coals
    Journal of Thermal Analysis and Calorimetry, 1997
    Co-Authors: Xiadong Yang, Wei-ping Pan, W Tomes, John T. Riley
    Abstract:

    The objective of this study was to examine the possible formation of chlorinated organic compounds during the combustion of blends of Refuse Derived Fuels (RDF) and coal under conditions similar to those of an atmospheric fluidized bed combustion (AFBC) system. A series of experiments were conducted using a TG interfaced to FTIR. Additional experiments using a tube furnace preheated to AFBC operating temperatures were also conducted. The combustion products were cryogenically trapped and analyzed with a GC/MS system. The chlorination of phenols and the condensation reactions of chlorophenols were investigated in this study. A possible mechanism for the formation of chlorinated organic compounds such as dibenzodioxins and dibenzofurans, by chlorination and condensation reactions involving phenols, was proposed.