AJAC  Vol.6 No.12 , November 2015
Temperature Fractionation (TF) of Hg Compounds in Gypsum from Wet Flue Gas Desulfurization System of the Coal Fired Thermal Power Plant (TPP)
Abstract: Gypsum from the wet flue gas desulfurization system of the lignite fired thermal power plant Sostanj, Slovenia, can efficiently retain mercury (Hg), of which most is contained in finer gypsum fractions, with concentrations above 10 kg-1. The aim of this work was to identify and study the temperature stability of Hg species in gypsum by a temperature fractionation (TF) method. A self-constructed apparatus was used that consisted of an electrical furnace for controlled heating up to 700°C, with a heating rate of 2.2°C·min-1, and an AAS detector with Zeeman background correction. The pattern of Hg release during temperature increase depends highly on the matrix/substrate in which it is contained. Based on spiking gypsum with known Hg compounds we concluded that the largest proportion of Hg in gypsum belongs to Hg-Cl and Hg-Br compounds appearing at 160°C to 200°C, followed by smaller amounts of HgO, HgS and Hg sulfates appearing at 300°C and 450°C. Further development of methodology for identifying Hg species would require identification of the decomposition fragments of Hg and other compounds, complemented by a better understanding of Hg reactivity at higher temperatures.
Cite this paper: Sedlar, M. , Pavlin, M. , Jaćimović, R. , Stergaršek, A. , Frkal, P. and Horvat, M. (2015) Temperature Fractionation (TF) of Hg Compounds in Gypsum from Wet Flue Gas Desulfurization System of the Coal Fired Thermal Power Plant (TPP). American Journal of Analytical Chemistry, 6, 939-956. doi: 10.4236/ajac.2015.612090.

[1]   UNEP Division of Technology, Industry and Economics, Chemicals Branch International Environment House (2013) Global Mercury Assessment 2013: Sources, Emissions, Releases and Environmental Transport.

[2]   (2013) UNEP Conference of Plenipotentiaries on the Minamata Convention on Mercury, Kumamoto, Japan, 10 and 11 October 2013. Text of the Minamata Convention on Mercury for Adoption by the Conference of Plenipotentiaries.

[3]   Galbreath, K.C. and Zygarlicke, C.J. (2000) Mercury Transformations in Coal Combustion Flue Gas. Fuel ProcessingTechnology, 65-66, 289-310.

[4]   Pavlish, J.H., Sondreal, E.A., Mann, M.D., Olson, E.S., Galbreath, K.C., Laudal, D.L., et al. (2003) Status Review of Mercury Control Options for Coal-Fired Power Plants. Fuel Processing Technology, 82, 89-165.

[5]   Niksa, S. and Fujiwara, N. (2005) Predicting Extents of Mercury Oxidation in Coal-Derived Flue Gases. Journal of the Air & Waste Management Association, 55, 930-939.

[6]   Stergarsek, A., Horvat, M., Kotnik, J., Tratnik, J., Frkal, P., Kocman, D., et al. (2008) The Role of Flue Gas Desulphurisation in Mercury Speciation and Distribution in a Lignite Burning Power Plant. Fuel, 87, 3504-3512.

[7]   Stergarsek, A., Horvat, M., Frkal, P. and Stergarsek, J. (2010) Removal of Hg-0 from Flue Gases in Wet FGD by Catalytic Oxidation with Air—An Experimental Study. Fuel, 89, 3167-3177.

[8]   Stergarsek, A., Horvat, M., Frkal, P., Guevara, S.R. and Kocjancic, R. (2013) Removal of Hg-0 in Wet FGD by Catalytic Oxidation with Air—A Contribution to the Development of a Process Chemical Model. Fuel, 107, 183-191.

[9]   Pudasainee, D., Kim, J.H., Yoon, Y.S. and Seo, Y.C. (2012) Oxidation, Reemission and Mass Distribution of Mercury in Bituminous Coal-Fired Power Plants with SCR, CS-ESP and Wet FGD. Fuel, 93, 312-318.

[10]   Yan, R., Gauthier, D. and Flamant, G. (2000) Possible Interactions between As, Se, and Hg during Coal Combustion. Combustion and Flame, 120, 49-60.

[11]   Yudovich, Y.E. and Ketris, M.P. (2005) Mercury in Coal: A Review Part 2. Coal Use and Environmental Problems. International Journal of Coal Geology, 62, 135-165.

[12]   Ito, S., Yokoyama, T. and Asakura, K. (2006) Emissions of Mercury and Other Trace Elements from Coal-Fired Power Plants in Japan. Science of the Total Environment, 368, 397-402.

[13]   Meij, R. and TeWinkel, B. (2004) The Emissions and Environmental Impact of PM10 and Trace Elements from a Modern Coal-Fired Power Plant Equipped with ESP and Wet FGD. Fuel Processing Technology, 85, 641-656.

[14]   Ochoa-González, R., Díaz-Somoano, M. and Mar-tínez-Tarazona, M.R. (2013) Effect of Anion Concentrations on Hg2+ Reduction from Simulated Desulphurization Aqueous Solutions. Chemical Engineering Journal, 214, 165-171.

[15]   Tang, T., Xu, J., Lu, R., Wo, J. and Xu, X. (2010) En-hanced Hg2+ Removal and Hg0 Re-Emission Control from Wet Fuel Gas Desulfurization Liquors with Additives. Fuel, 89, 3613-3617.

[16]   Wu, C.L., Cao, Y., He, C.C., Dong, Z.B. and Pan, W.P. (2010) Study of Elemental Mercury Re-Emission through a Lab-Scale Simulated Scrubber. Fuel, 89, 2072-2080.

[17]   Ochoa-González, R., Díaz-Somoano, M. and Martínez-Tarazona, M.R. (2013) Control of Hg0 Re-Emission from Gypsum Slurries by Means of Additives in Typical Wet Scrubber Conditions. Fuel, 105, 112-118.

[18]   Milobowski, M.G., Amrhein, G.T., Kudlac, G.A. and Yurchison, D.M. (2001) Wet FGD Enhanced Mercury Control for Coal-Fired Utility Boilers. Proceedings of the US EPA/DOE/EPRI Combined Power Plant Air. Pollutant Control Symposium: The Mega Symposium, Chicago, 20-23 August 2001.

[19]   Beatty, W.L., Schroeder, K. and Beatty, C.L.K. (2012) Mineralogical Associations of Mercury in FGD Products. Energy Fuels, 26, 3399-3406.

[20]   Liu, X., Wang, S., Zhang, L., Wu, Y., Duan, L. and Hao, J. (2013) Speciation of Mercury in FGD Gypsum and Mercury Emission during the Wallboard Production in China. Fuel, 111, 621-627.

[21]   Heebink, L.V. and Hassett, D.J. (2005) Mercury Release from FGD. Fuel, 84, 1372-1377.

[22]   Biester, H. and Scholz, C. (1996) Determination of Mercury Binding Forms in Contaminated Soils: Mercury Pyrolysis versus Sequential Extractions. Environmental Science & Technology, 31, 233-239.

[23]   Issaro, N., Abi-Ghanem, C. and Bermond, A. (2009) Fractionation Studies of Mercury in Soils and Sediments: A Review of the Chemical Reagents Used for Mercury Extraction. Analytica Chimica Acta, 631, 1-12.

[24]   Do Valle, C.M., Santana, G.P. and Windmoller, C.C. (2006) Mercury Conversion Processes in Amazon Soils Evaluated by Thermodesorption Analysis. Chemosphere, 65, 1966-1975.

[25]   Windmoller, C.C., Wilken, R.D. and Jardim, W.D. (1996) Mercury Speciation in Contaminated Soils by Thermal Release Analysis. Water, Air, & Soil Pollution, 89, 399-416.

[26]   Rumayor, M., Diaz-Somoano, M., Lopez-Anton, M.A. and Martinez-Tarazona, M.R. (2013) Mercury Compounds Characterization by Thermal Desorption. Talanta, 114, 318-322.

[27]   Navarro, A., Canadas, I., Martinez, D., Rodriguez, J. and Mendoza, J.L. (2009) Application of Solar Thermal Desorption to Remediation of Mercury-Contaminated Soils. Solar Energy, 89, 1405-1414.

[28]   Coufalík, P., Zvěrina, O. and Komárek, J. (2014) Determination of Mercury Species Using Thermal Desorption Analysis in AAS. Chemical Papers, 68, 427-434.

[29]   Coufalík, P., Krásensky, P., Dosbaba, M. and Komárek, J. (2012) Sequential Extraction and Thermal Desorption of Mercury from Contaminated Soil and Tailings from Mongolia. Central European Journal of Chemistry, 10, 1565-1573.

[30]   Rallo, M., Lopez-Anton, M.A., Perry, R. and Maroto-Valer, M.M. (2010) Mercury Speciation in Gypsums Produced from Flue Gas Desulfurization by Temperature Programmed Decomposition. Fuel, 89, 2157-2159.

[31]   Murakami, A., Uddin, M.A., Ochiai, R., Sasaoka, E. and Wu, S. (2010) Study of the Mercury Sorption Mechanism on Activated Carbon in Coal Combustion Flue Gas by the Temperature-Programmed Decomposition Desorption Technique. Energy & Fuels, 24, 4241-4249.

[32]   Wu, S., Uddin, M.A., Nagano, S., Ozaki, M. and Sasaoka, E. (2011) Fundamental Study on Decomposition Characteristics of Mercury Compounds over Solid Powder by Temperature-Programmed Decomposition Desorption Mass Spectrometry. Energy & Fuels, 25, 144-153.

[33]   Raposo, C., Windmoller, C.C. and Durao Jr., W.A. (2003) Mercury Speciation in Fluorescent Lamps by Thermal Release Analysis. Waste Management, 23, 879-886.

[34]   Lopez-Anton, M.A., Yuan, Y., Perry, R. and Maro-to-Valer, M.M. (2010) Analysis of Mercury Species Present during Coal Combustion by Thermal Desorption. Fuel, 89, 629-634.

[35]   Luo, G., Yao, H., Xu, M., Gupta, R. and Xu, Z. (2011) Identifying Modes of Occurrence of Mercury in Coal by Temperature Programmed Pyrolysis. Proceedings of the Combustion Institute, 33, 2763-2769.

[36]   Shuvaeva, O.V., Gustaytis, M.A. and Anoshin, G.N. (2008) Mercury Speciation in Environmental Solid Samples Using Thermal Release Technique with Atomic Absorption Detection. Analytica Chimica Acta, 621, 148-154.

[37]   Biester, H., Müller, G. and Scholer, H.F. (2002) Binding and Mobility of Mercury in Soils Contaminated by Emissions from Chlor-Alkali Plants. Science of the Total Environment, 284, 191-203.

[38]   Bollen, A., Wenke, A. and Biester, H. (2008) Mercury Speciation Analyses in HgCl2-Contaminated Soils and Groundwater—Implications for Risk Assessment and Remediation Strategies. Water Research, 42, 91-100.

[39]   Biester, H., Gosar, M. and Müller, G. (1999) Mercury Speciation in Tailings of the Idrija Mercury Mine. Journal of Geochemical Exploration, 65, 195-204.

[40]   Ochoa-Gonzalez, R., Diaz-Somoano, M. and Martinez-Tarazona, M.R. (2013) Influence of Limestone Characteristics on Mercury Re-Emission in WFGD Systems. Environmental Science & Technology, 47, 2974-2981.

[41]   Kairies, C., Schroeder, K. and Cardone, C. (2006) Mercury in Gypsum Produced from Flue Gas Desulfurization. Fuel, 85, 2530-2536.

[42]   Cornell, R.M. and Schwertmann, U. (2003) The Iron Oxides: Structure, Properties, Reactions, Occurrences and Uses. 2nd Edition, Wiley-VCH, Weinheim.

[43]   Kim, C.S., Rytuba, J.J. and Brown, G.E. (2004) EXAFS Study of Mercury(II) Sorption to Fe- and Al-(Hydr)oxides. Journal of Colloid and Interface Science, 270, 9-20.

[44]   Evans, M.A. and Elmore, R.D. (2006) Fluid Control of Localized Mineral Domains in Limestone Pressure Solution Structures. Journal of Structural Geology, 28, 284-301.

[45]   Kotnik, J., Horvat, M., Mandic, V. and Logar, M. (2000) Influence of the Sodsanj Coal-Fired Thermal Power Plant on Mercury and Methyl Mercury Concentrations in Lake Velenje, Slovenia. Science of the Total Environment, 259, 85-95.

[46]   Akagi, H. and Nishimura, H. (1991) Speciation of Mercury in the Environment. In: Suzuki, T., Imura, N. and Clarkson, T.W., Eds., Advances in Mercury Toxicology, Plenum Press, New York, 53-76.

[47]   Jacimovic, R., Smodis, B., Bucar, T. and Stegnar, P. (2003) K0-NAA Quality Assessment by Analysis of Different Certified Reference Materials Using the KAYZERO/SOLCOI Software. Journal of Radioanalytical and Nuclear Chemistry, 257, 659-663.

[48]   Smodis, B., Jacimovic, R., Medin, G. and Jovanovic, S. (1993) Instrumental Neutron Activation Analysis of Sediment Reference Materials Using the K0-Standardisation Method. Journal of Radioanalytical and Nuclear Chemistry, 169, 177-185.

[49]   Kayzero for Windows (KayWin®), User’s Manual for Reactor Neutron Activation Analysis (NAA) Using the K0 Standardization Method, Version 2, November 2005.

[50]   Sholupov, S., Pogarev, S., Ryzhov, V., Mashyanov, N. and Stroganov, A. (2004) Zeeman Atomic Absorption Spectrometer RA-915+ for Direct Determination of Mercury in Air and Complex Matrix Samples. Fuel Processing Technology, 85, 473-485.

[51]   Sedlar, M., Pavlin, M., Popovic, A. and Horvat, M. (2015) Temperature Stability of Mercury Compounds in Solid Substrates. Open Chemistry, 13, 404-419.

[52]   Acuna-Caro, C., Brechtel, K., Scheffknecht, G. and Braß, M. (2009) The Effect of Chlorine and Oxygen Concentrations on the Removal of Mercury at an FGD-Batch Reactor. Fuel, 88, 2489-2494.

[53]   Blythe, G., DeBerry, D., Marsh, B., Paradis, J., Range, J. and Rhudy, R. (2004) Bench-Scale Evaluation of the Fate of Mercury in Wet FGD Systems. Proceedings of the Air and Waste Management Association’s Combined Power Plant Air Pollution Control Mega Symposium, Washington DC, 30 August-2 September 2004, Paper No. 59.

[54]   Guminski, C. (2001) The F-Hg System (Fluorine-Mercury). Journal of Phase Equilibria, 22, 578-581.

[55]   Tariq, S.A. and Hill, J.O. (1981) Thermal Analysis of Mercury(I) Sulfate and Mercury(II) Sulphate. Journal of Thermal Analysis, 21, 277-281.

[56]   Wendlandt, W.W. (1974) Thermal Properties of Inorganic Compounds. Hg(I) Hg(II) Compounds. Thermochimica Acta, 10, 101-107.

[57]   L’vov, B.V. (1999) Kinetics and Mechanisms of Thermal Decomposition of Mercuric Oxide. Thermochimica Acta, 333, 21-26.

[58]   Leckey, J.H. and Nulf, L.E. (1994) Thermal Decomposition of Mercuric Sulfide. Chemistry and Chemical Engineering Department—Development Organization. Oak Ridge Y-12 Plant. Martin Marietta Energy Systems, Inc., US Department of Energy, Tennessee.