Quecksilber aus thermischen Kraftwerken: Freisetzung‐ und Umwandlungsmechanismen sowie Möglichkeiten zur Minderung

Die weitere Absenkung der Emissionen von Quecksilber aus fossil befeuerten Kraftwerken erfordert eine Verbesserung der bestehenden Rauchgasreinigungssysteme oder den Einsatz von neuen oder adaptierten Prozessen. Dabei konnen spezielle Adsorbentien, zur Quecksilberoxidation verbesserte SCR-DeNOx-Katalysatoren oder Additive zur Quecksilberumwandlung und Abscheidung in nassen Rauchgasentschwefelungsanlagen eigesetzt werden. Da die chemischen Zusammenhange der verschiedenen Quecksilberspezies von den Betriebsparametern der einzelnen Rauchgasreinigungsanlagen abhangen, ist ein detailliertes Verstandnis der Vorgange bei der Quecksilberruckhaltung von groser Bedeutung. The reduction of mercury emissions from fossil fired power plants is of major concern. The optimization and the improvement of the existing flue gas cleaning devices or the use of special equipment for mercury removal are possible ways. Therefore the use of sorbents, the optimization of SCR-DeNOx-catalysts and the utilization of additive to enhance the mercury oxidation and the separation in wet flue gas desulfurization are only some discussed technologies. As the behavior of all mercury species in flue gas depends on the operational parameters of the power plant and the special flue gas cleaning device, it is essential to understand the chemistry and the interaction of the different cleaning devices.

[1]  Steven A. Benson,et al.  Status review of mercury control options for coal-fired power plants , 2003 .

[2]  Hiroyuki Kamata,et al.  Mercury oxidation by hydrochloric acid over TiO2 supported metal oxide catalysts in coal combustion flue gas , 2009 .

[3]  K. E. Redinger,et al.  Demonstration of additive use for enhanced mercury emissions control in wet FGD systems , 2004 .

[4]  T. Ho.  Hard soft acids bases (HSAB) principle and organic chemistry , 1975 .

[5]  Yue Liu,et al.  Experimental study on the absorption behaviors of gas phase bivalent mercury in Ca-based wet flue gas desulfurization slurry system. , 2010, Journal of hazardous materials.

[6]  T. R. Griffiths,et al.  The electronic spectra of the mixed mercury dihalides. Part 1. Computational procedures for calculating spectra, for a new route to equilibrium and formation constants, and the resolved spectra , 1980 .

[7]  T. Lee,et al.  Structural effect of the in situ generated titania on its ability to oxidize and capture the gas-phase elemental mercury. , 2006, Chemosphere.

[8]  Xinbin Feng,et al.  Modes of occurrence of mercury in coals from Guizhou, People's Republic of China , 1999 .

[9]  John C. S. Chang,et al.  Simulation and evaluation of elemental mercury concentration increase in flue gas across a wet scrubber. , 2003, Environmental science & technology.

[10]  Constance Senior.  Review of the role of aqueous chemistry in mercury removal by acid gas scrubbers on incinerator systems , 2007 .

[11]  A. Trotman‐Dickenson,et al.  ‘Comprehensive’ Inorganic Chemistry , 1958, Nature.

[12]  S. Niksa,et al.  A Predictive Mechanism for Mercury Oxidation on Selective Catalytic Reduction Catalysts under Coal-Derived Flue Gas , 2005, Journal of the Air & Waste Management Association.

[13]  T. R. Griffiths,et al.  The electronic spectra of the mixed mercury dihalides. Part 2. Identification, equilibrium and formation constants, and assignment of transitions , 1980 .

[14]  W. Pan,et al.  Impacting Factors of Elemental Mercury Re-emission across a Lab-scale Simulated Scrubber , 2010 .

[15]  S. Benson,et al.  Thermochemistry of the Deacon Process , 1995 .

[16]  Jung-Bin Lee,et al.  Characteristics of commercial selective catalytic reduction catalyst for the oxidation of gaseous elemental mercury with respect to reaction conditions , 2010 .

[17]  C. Romero,et al.  Study of elemental mercury re-emission in a simulated wet scrubber , 2012 .

[18]  Rafael Kandiyoti,et al.  The Influence of Injected HCl and SO2 on the Behavior of Trace Elements during Wood-Bark Combustion , 2003 .

[19]  A. Presto,et al.  Survey of catalysts for oxidation of mercury in flue gas. , 2006, Environmental science & technology.

[20]  Y. Zhuang,et al.  Impact of calcium chloride addition on mercury transformations and control in coal flue gas , 2007 .

[21]  Akira Miyamoto,et al.  Mechanism of the reaction of NO and NH3 on vanadium oxide catalyst in the presence of oxygen under the dilute gas condition , 1980 .

[22]  R. Meij,et al.  The Fate and Behavior of Mercury in Coal-Fired Power Plants , 2002, Journal of the Air & Waste Management Association.

[23]  MA Zhuang-wei,et al.  The estimation of mercury emission from coal combustion in China. , 2000 .

[24]  Yue Liu,et al.  A mechanism study of chloride and sulfate effects on Hg2+ reduction in sulfite solution , 2011 .

[25]  Michael D Durham.  A Special Issue from the U.S. EPA/DOE/EPRI Combined Power Plant Air Pollutant Control Symposium: The Mega Symposium and the A&WMA Specialty Conference on Mercury Emissions: Fate, Effects, and Control , 2002, Journal of the Air & Waste Management Association.

[26]  R. Byrne,et al.  Chemical speciation of environmentally significant heavy metals with inorganic ligands. Part 1: The Hg2+– Cl–, OH–, CO32–, SO42–, and PO43– aqueous systems (IUPAC Technical Report) , 2005 .

[27]  R. Vidic,et al.  Uptake of Elemental Mercury Vapors by Activated Carbons. , 1996, Journal of the Air & Waste Management Association.

[28]  Meng Zhang,et al.  Hg2+ reduction and re-emission from simulated wet flue gas desulfurization liquors. , 2009, Journal of Hazardous Materials.