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Haitao Su - One of the best experts on this subject based on the ideXlab platform.

  • mercury transformation and speciation in flue gases from anthropogenic emission sources a critical review
    Atmospheric Chemistry and Physics, 2015
    Co-Authors: Lei Zhang, Qingru Wu, Fengyang Wang, Leiming Zhang, Shuxiao Wang, Mei Yang, Haitao Su
    Abstract:

    Abstract. Mercury transformation mechanisms and speciation profiles are reviewed for mercury formed in and released from flue gases of coal-fired boilers, non-ferrous metal smelters, Cement plants, iron and steel plants, waste incinerators, biomass burning and so on. Mercury in coal, ores, and other raw materials is released to flue gases in the form of Hg0 during combustion or smelting in boilers, kilns or furnaces. Decreasing temperature from over 800 °C to below 300 °C in flue gases leaving boilers, kilns or furnaces promotes homogeneous and heterogeneous oxidation of Hg0 to gaseous divalent mercury (Hg2+), with a portion of Hg2+ adsorbed onto fly ash to form particulate-bound mercury (Hgp). Halogen is the primary oxidizer for Hg0 in flue gases, and active components (e.g., TiO2, Fe2O3, etc.) on fly ash promote heterogeneous oxidation and adsorption processes. In addition to mercury removal, mercury transformation also occurs when passing through air pollution control devices (APCDs), affecting the mercury speciation in flue gases. In coal-fired power plants, selective catalytic reduction (SCR) system promotes mercury oxidation by 34–85 %, electrostatic precipitator (ESP) and fabric filter (FF) remove over 99 % of Hgp, and wet flue gas desulfurization system (WFGD) captures 60–95 % of Hg2+. In non-ferrous metal smelters, most Hg0 is converted to Hg2+ and removed in acid plants (APs). For Cement Clinker Production, mercury cycling and operational conditions promote heterogeneous mercury oxidation and adsorption. The mercury speciation profiles in flue gases emitted to the atmosphere are determined by transformation mechanisms and mercury removal efficiencies by various APCDs. For all the sectors reviewed in this study, Hgp accounts for less than 5 % in flue gases. In China, mercury emission has a higher Hg0 fraction (66–82 % of total mercury) in flue gases from coal combustion, in contrast to a greater Hg2+ fraction (29–90 %) from non-ferrous metal smelting, Cement and iron and/or steel Production. The higher Hg2+ fractions shown here than previous estimates may imply stronger local environmental impacts than previously thought, caused by mercury emissions in East Asia. Future research should focus on determining mercury speciation in flue gases from iron and steel plants, waste incineration and biomass burning, and on elucidating the mechanisms of mercury oxidation and adsorption in flue gases.

  • mercury transformation and speciation in flue gases from anthropogenic emission sources a critical review
    Atmospheric Chemistry and Physics, 2015
    Co-Authors: Lei Zhang, Qingru Wu, Fengyang Wang, Leiming Zhang, Shuxiao Wang, Mei Yang, Haitao Su
    Abstract:

    Abstract. Mercury transformation mechanisms and speciation profiles are reviewed for mercury formed in and released from flue gases of coal-fired boilers, non-ferrous metal smelters, Cement plants, iron and steel plants, waste incinerators, biomass burning and so on. Mercury in coal, ores, and other raw materials is released to flue gases in the form of Hg0 during combustion or smelting in boilers, kilns or furnaces. Decreasing temperature from over 800 °C to below 300 °C in flue gases leaving boilers, kilns or furnaces promotes homogeneous and heterogeneous oxidation of Hg0 to gaseous divalent mercury (Hg2+), with a portion of Hg2+ adsorbed onto fly ash to form particulate-bound mercury (Hgp). Halogen is the primary oxidizer for Hg0 in flue gases, and active components (e.g., TiO2, Fe2O3, etc.) on fly ash promote heterogeneous oxidation and adsorption processes. In addition to mercury removal, mercury transformation also occurs when passing through air pollution control devices (APCDs), affecting the mercury speciation in flue gases. In coal-fired power plants, selective catalytic reduction (SCR) system promotes mercury oxidation by 34–85 %, electrostatic precipitator (ESP) and fabric filter (FF) remove over 99 % of Hgp, and wet flue gas desulfurization system (WFGD) captures 60–95 % of Hg2+. In non-ferrous metal smelters, most Hg0 is converted to Hg2+ and removed in acid plants (APs). For Cement Clinker Production, mercury cycling and operational conditions promote heterogeneous mercury oxidation and adsorption. The mercury speciation profiles in flue gases emitted to the atmosphere are determined by transformation mechanisms and mercury removal efficiencies by various APCDs. For all the sectors reviewed in this study, Hgp accounts for less than 5 % in flue gases. In China, mercury emission has a higher Hg0 fraction (66–82 % of total mercury) in flue gases from coal combustion, in contrast to a greater Hg2+ fraction (29–90 %) from non-ferrous metal smelting, Cement and iron and/or steel Production. The higher Hg2+ fractions shown here than previous estimates may imply stronger local environmental impacts than previously thought, caused by mercury emissions in East Asia. Future research should focus on determining mercury speciation in flue gases from iron and steel plants, waste incineration and biomass burning, and on elucidating the mechanisms of mercury oxidation and adsorption in flue gases.

Nele De Belie - One of the best experts on this subject based on the ideXlab platform.

  • sulfates in completely recyclable concrete and the effect of caso4 on the Clinker mineralogy
    Construction and Building Materials, 2017
    Co-Authors: Mieke De Schepper, Klaartje De Buysser, Isabel Van Driessche, Philip Van Den Heede, Eleni C Arvaniti, Nele De Belie
    Abstract:

    Abstract To increase the recycling potential of concrete, Completely Recyclable Concrete (CRC) has been developed to be used as a raw material for Cement Clinker Production. Sulfates may penetrate CRC structures in time and their presence could affect the Clinkering process of the eventually obtained CRC rubble. Therefore, the effect of CaSO 4 additions on the final CRC Clinker mineralogy has been investigated using XRD/Rietveld and SEM/EDX. An increasing sulfate content was found to stimulate the formation of sulfates that incorporate CaO, i.e. calcium langbeinite and anhydrite. Moreover, belite tends to be stabilized at the expense of alite with more SO 3 present.

  • fines extracted from recycled concrete as alternative raw material for portland Cement Clinker Production
    Cement & Concrete Composites, 2015
    Co-Authors: Joris Schoon, Klaartje De Buysser, Isabel Van Driessche, Nele De Belie
    Abstract:

    Abstract This paper aims to examine the use of fines generated out of recycled aggregates Production as an alternative raw material for Portland Clinker kilns with enumeration of possible limitations. Different technical set-ups were used to separate these fines from the recycled aggregates. The relationship between the particle size distribution of the generated fines fraction and their chemical composition as well as the relationship between the final filler (

Lei Zhang - One of the best experts on this subject based on the ideXlab platform.

  • mercury transformation and speciation in flue gases from anthropogenic emission sources a critical review
    Atmospheric Chemistry and Physics, 2015
    Co-Authors: Lei Zhang, Qingru Wu, Fengyang Wang, Leiming Zhang, Shuxiao Wang, Mei Yang, Haitao Su
    Abstract:

    Abstract. Mercury transformation mechanisms and speciation profiles are reviewed for mercury formed in and released from flue gases of coal-fired boilers, non-ferrous metal smelters, Cement plants, iron and steel plants, waste incinerators, biomass burning and so on. Mercury in coal, ores, and other raw materials is released to flue gases in the form of Hg0 during combustion or smelting in boilers, kilns or furnaces. Decreasing temperature from over 800 °C to below 300 °C in flue gases leaving boilers, kilns or furnaces promotes homogeneous and heterogeneous oxidation of Hg0 to gaseous divalent mercury (Hg2+), with a portion of Hg2+ adsorbed onto fly ash to form particulate-bound mercury (Hgp). Halogen is the primary oxidizer for Hg0 in flue gases, and active components (e.g., TiO2, Fe2O3, etc.) on fly ash promote heterogeneous oxidation and adsorption processes. In addition to mercury removal, mercury transformation also occurs when passing through air pollution control devices (APCDs), affecting the mercury speciation in flue gases. In coal-fired power plants, selective catalytic reduction (SCR) system promotes mercury oxidation by 34–85 %, electrostatic precipitator (ESP) and fabric filter (FF) remove over 99 % of Hgp, and wet flue gas desulfurization system (WFGD) captures 60–95 % of Hg2+. In non-ferrous metal smelters, most Hg0 is converted to Hg2+ and removed in acid plants (APs). For Cement Clinker Production, mercury cycling and operational conditions promote heterogeneous mercury oxidation and adsorption. The mercury speciation profiles in flue gases emitted to the atmosphere are determined by transformation mechanisms and mercury removal efficiencies by various APCDs. For all the sectors reviewed in this study, Hgp accounts for less than 5 % in flue gases. In China, mercury emission has a higher Hg0 fraction (66–82 % of total mercury) in flue gases from coal combustion, in contrast to a greater Hg2+ fraction (29–90 %) from non-ferrous metal smelting, Cement and iron and/or steel Production. The higher Hg2+ fractions shown here than previous estimates may imply stronger local environmental impacts than previously thought, caused by mercury emissions in East Asia. Future research should focus on determining mercury speciation in flue gases from iron and steel plants, waste incineration and biomass burning, and on elucidating the mechanisms of mercury oxidation and adsorption in flue gases.

  • mercury transformation and speciation in flue gases from anthropogenic emission sources a critical review
    Atmospheric Chemistry and Physics, 2015
    Co-Authors: Lei Zhang, Qingru Wu, Fengyang Wang, Leiming Zhang, Shuxiao Wang, Mei Yang, Haitao Su
    Abstract:

    Abstract. Mercury transformation mechanisms and speciation profiles are reviewed for mercury formed in and released from flue gases of coal-fired boilers, non-ferrous metal smelters, Cement plants, iron and steel plants, waste incinerators, biomass burning and so on. Mercury in coal, ores, and other raw materials is released to flue gases in the form of Hg0 during combustion or smelting in boilers, kilns or furnaces. Decreasing temperature from over 800 °C to below 300 °C in flue gases leaving boilers, kilns or furnaces promotes homogeneous and heterogeneous oxidation of Hg0 to gaseous divalent mercury (Hg2+), with a portion of Hg2+ adsorbed onto fly ash to form particulate-bound mercury (Hgp). Halogen is the primary oxidizer for Hg0 in flue gases, and active components (e.g., TiO2, Fe2O3, etc.) on fly ash promote heterogeneous oxidation and adsorption processes. In addition to mercury removal, mercury transformation also occurs when passing through air pollution control devices (APCDs), affecting the mercury speciation in flue gases. In coal-fired power plants, selective catalytic reduction (SCR) system promotes mercury oxidation by 34–85 %, electrostatic precipitator (ESP) and fabric filter (FF) remove over 99 % of Hgp, and wet flue gas desulfurization system (WFGD) captures 60–95 % of Hg2+. In non-ferrous metal smelters, most Hg0 is converted to Hg2+ and removed in acid plants (APs). For Cement Clinker Production, mercury cycling and operational conditions promote heterogeneous mercury oxidation and adsorption. The mercury speciation profiles in flue gases emitted to the atmosphere are determined by transformation mechanisms and mercury removal efficiencies by various APCDs. For all the sectors reviewed in this study, Hgp accounts for less than 5 % in flue gases. In China, mercury emission has a higher Hg0 fraction (66–82 % of total mercury) in flue gases from coal combustion, in contrast to a greater Hg2+ fraction (29–90 %) from non-ferrous metal smelting, Cement and iron and/or steel Production. The higher Hg2+ fractions shown here than previous estimates may imply stronger local environmental impacts than previously thought, caused by mercury emissions in East Asia. Future research should focus on determining mercury speciation in flue gases from iron and steel plants, waste incineration and biomass burning, and on elucidating the mechanisms of mercury oxidation and adsorption in flue gases.

  • Mercury transformation and speciation in flue gases from anthropogenic emission sources: a critical review
    Copernicus Publications, 2015
    Co-Authors: Lei Zhang, S. X. Wang, F. Y. Wang, C.-j. Lin, L. M. Zhang, M. L. Hui, J. M. Hao
    Abstract:

    Mercury transformation mechanisms and speciation profiles are reviewed for mercury formed in and released from flue gases of coal-fired boilers, non-ferrous metal smelters, Cement plants, iron and steel plants, municipal solid waste incinerators, and biomass burning. Mercury in coal, ores and other raw materials is released to flue gases in the form of Hg0 during combustion or smelting in boilers, kilns or furnaces. Decreasing temperature from over 800 °C to below 300 °C in flue gases leaving boilers, kilns or furnaces promotes homogeneous and heterogeneous oxidation of gaseous elemental mercury (Hg0) to gaseous divalent mercury (Hg2+), with a portion of Hg2+ adsorbed onto fly ash to form particulate-bound mercury (Hgp). Halogen is the primary oxidizer for Hg0 in flue gases, and active components (e.g.,TiO2, Fe2O3, etc.) on fly ash promote heterogeneous oxidation and adsorption processes. In addition to mercury removal, mercury transformation also occurs when passing through air pollution control devices (APCDs), affecting the mercury speciation in flue gases. In coal-fired power plants, selective catalytic reduction (SCR) system promotes mercury oxidation by 34–85 %, electrostatic precipitator (ESP) and fabric filter (FF) remove over 99 % of Hgp, and wet flue gas desulfurization system (WFGD) captures 60–95 % of Hg2+. In non-ferrous metal smelters, most Hg0 is converted to Hg2+ and removed in acid plants (APs). For Cement Clinker Production, mercury cycling and operational conditions promote heterogeneous mercury oxidation and adsorption. The mercury speciation profiles in flue gases emitted to the atmosphere are determined by transformation mechanisms and mercury removal efficiencies by various APCDs. For all the sectors reviewed in this study, Hgp accounts for less than 5 % in flue gases. In China, mercury emission has a higher fraction (66–82 % of total mercury) in flue gases from coal combustion, in contrast to a greater Hg2+ fraction (29–90 %) from non-ferrous metal smelting, Cement and iron/steel Production. The higher Hg2+ fractions shown here than previous estimates may imply stronger local environmental impacts than previously thought, caused by mercury emissions in East Asia. Future research should focus on determining mercury speciation in flue gases from iron and steel plants, waste incineration and biomass burning, and on elucidating the mechanisms of mercury oxidation and adsorption in flue gases

Hilal Al S Dhamri - One of the best experts on this subject based on the ideXlab platform.

  • oil based mud cutting as an additional raw material in Clinker Production
    Journal of Hazardous Materials, 2020
    Co-Authors: Sabah A Abdulwahab, Hilal Al S Dhamri, Costas A Velis, Leon Black
    Abstract:

    Abstract Oil-Based Mud (OBM) cutting is a hazardous by-product generated during oil-well drilling. Its chemical composition suggests that it might be suitable as a raw material in Cement manufacturing. It is rich in calcium oxide, silica, and aluminium oxide, which are the major oxides in raw materials for Cement manufacturing. In this research, OBM cutting is used as a constituent of the raw meal for Cement Clinker Production. Raw meal mixtures were prepared by mixing different ratios of raw materials increasing OBM content. The impact of the addition of OBM cutting on the resulting Clinker has been investigated. The results demonstrate that OBM cutting could be recycled in the manufacturing of Portland Cement Clinker. Clinker prepared using OBM cutting had very similar properties to that prepared from limestone. This result could represent an opportunity for solving an environmental problem. The addition of OBM cutting lowers the calcination temperature, and increases the rate of carbonate dissociation. However, it also leads to a higher free lime in Clinker, which is a result of the presence of trace elements, such as barium. Overall, its use as a raw material in Cement Production could provide a cost-effective, environment-friendly route for the management of OBM cutting.

Sergi Martinezramirez - One of the best experts on this subject based on the ideXlab platform.

  • the effect of using thermally dried sewage sludge as an alternative fuel on portland Cement Clinker Production
    Journal of Cleaner Production, 2013
    Co-Authors: Nuria Rodríguez, Shane Donatello, Manel Guillem, Joan Puig, Enric Larrotcha, Sergi Martinezramirez, Maria Teresa Blancovarela, Josep Flores
    Abstract:

    This study considers the potential of a sewage sludge previously dried using a novel drying process as an alternative fuel in the Cement industry. A comprehensive characterisation study of the sewage sludge is presented. The calorific value of the sludge was around 8300 J/g, easily meeting Cement industry requirements of 6250 J/g. To account for inorganic ashes that would remain from sewage sludge after burning, it was found that up to 14% of the raw materials used in Cement manufacture could be replaced with sewage sludge, without changing important raw meal moduli. It was estimated that the sludge raw meal would reduce fossil fuel consumption in a modern Cement kiln by around 70%. Clinkers made from sewage sludge containing raw meal had consistently lower free lime contents. However, a slight increase in belite formation was also noted due to the presence of P from the sewage sludge component.

  • ceramic wastes as alternative raw materials for portland Cement Clinker Production
    Cement & Concrete Composites, 2008
    Co-Authors: Francisca Puertas, Maria F Gazulla, A Barba, M P Gomez, Irene Garciadiaz, Marta Palacios, Sergi Martinezramirez
    Abstract:

    Abstract The Cement industry has for some time been seeking procedures that would effectively reduce the high energy and environmental costs of Cement manufacture. One such procedure is the use of alternative materials as partial replaCements for fuel, raw materials or even Clinker. The present study explores the reactivity and burnability of Cement raw mixes containing fired red or white ceramic wall tile wastes and combinations of the two as alternative raw materials. The results showed that the new raw mixes containing this kind of waste to be technically viable, and to have higher reactivity and burnability than a conventional mix, providing that the particle size of the waste used is lower than 90 μm. The mineralogical composition and distribution in the experimental Clinker prepared were comparable to the properties of the Clinker manufactured with conventional raw materials. Due to the presence of oxides such as ZnO, ZrO 2 and B 2 O 3 in tile glazing, the content of these oxides was higher in Clinker made with such waste. The mix of red and white ceramic wall tile waste was found to perform equally or better than each type of waste separately, a promising indication that separation of the two would be unnecessary for the purpose described above.