Mass spectrometric investigations on the release of inorganic species during gasification and combustion of German hard coals

Abstract Na-, K-, Cl-, and S-species released during thermal conversion of coal can cause several problems such as fouling, slagging and corrosion, especially in gas turbines and heat recovery systems. To reduce this problems an enhanced understanding of the underlying release mechanisms for Na-, K-, Cl-, and S-species is needed. Therefore, basic investigations have been performed in an atmospheric lab-scale tube furnace at 1400 °C under gasification and combustion conditions. Hot gas analysis has been carried out by molecular beam mass spectrometry. The release of H2S, HCl, K+, NaCl, COS, and SO2 has been qualitative and quantitative analysed and correlated with the coal composition. The results show a strong dependence of coal composition and reaction atmosphere on the release of Na-, K-, Cl-, and S-species. Additionally, thermodynamic equilibrium calculations with the software package FactSage 5.4.1 have been undertaken for comparison with the experimental results.

[1]  Michael Müller,et al.  Influence of Coal Composition and Operating Conditions on the Release of Alkali Species During Combustion of Hard Coal , 2007 .

[2]  F. Shadman,et al.  The kinetics and mechanism of alkali removal from flue gases by solid sorbents , 1990 .

[3]  J. Pettersson,et al.  A surface ionization instrument for on-line measurements of alkali metal components in combustion: Instrument description and applications , 2002 .

[4]  Bruce G. Miller,et al.  Chlorine in Solid Fuels Fired in Pulverized Fuel Boilers — Sources, Forms, Reactions, and Consequences: a Literature Review† , 2009 .

[5]  G. A Osborn,et al.  Review of sulphur and chlorine retention in coal-fired boiler deposits , 1992 .

[6]  D. Chandra,et al.  Mineral Impurities in Coal Combustion , 1986 .

[7]  D. Dayton,et al.  The direct observation of alkali vapor species in biomass combustion and gasification , 1994 .

[8]  M. P. Ketris,et al.  Chlorine in coal : A review , 2006 .

[9]  D. Dayton,et al.  Direct Observation of Alkali Vapor Release during Biomass Combustion and Gasification. 1. Application of Molecular Beam/Mass Spectrometry to Switchgrass Combustion , 1995 .

[10]  Michael Müller,et al.  Influence of coal composition on the release of Na-, K-, Cl-, and S-species during the combustion of brown coal , 2007 .

[11]  H. Spliethoff,et al.  Alkali Metals in Circulating Fluidized Bed Combustion of Biomass and Coal: Measurements and Chemical Equilibrium Analysis , 2005 .

[12]  A. Wokaun,et al.  Qualitative Evaluation of Alkali Release during the Pyrolysis of Biomass , 2007 .

[13]  P. Monkhouse,et al.  On-line diagnostic methods for metal species in industrial process gas , 2002 .

[14]  D. Thompson,et al.  The mobilisation of sodium and potassium during coal combustion and gasification , 1999 .

[15]  T. Wall,et al.  Alkali-ash reactions and deposit formation in pulverized-coal-fired boilers: the thermodynamic aspects involving silica, sodium, sulphur and chlorine , 1982 .

[16]  K. Kitano,et al.  Some relationships between coal rank and chemical and mineral composition , 1996 .

[17]  Anders Nordin,et al.  Effect of Coal Minerals on Chlorine and Alkali Metals Released during Biomass/Coal Cofiring , 1999 .

[18]  Michael Müller,et al.  Release of K, Cl, and S species during co-combustion of coal and straw , 2006 .

[19]  C A Moses,et al.  Impact study on the use of biomass-derived fuels in gas turbines for power generation , 1994 .

[20]  M. Soltys,et al.  Direct mass-spectrometric studies of the pyrolysis of carbonaceous fuels: II. Qualitative observations of primary and secondary processes in biomass , 1983 .

[21]  B. Bonn,et al.  In-situ study of the effect of operating conditions and additives on alkali emissions in fluidised bed combustion , 2002 .

[22]  Noam Lior,et al.  Energy resources and use : The present situation and possible paths to the future , 2008 .

[23]  G. Nathan,et al.  Quantitative measurement of atomic sodium in the plume of a single burning coal particle , 2008 .

[24]  J. Agnew,et al.  Transformations of sodium during gasification of low-rank coal , 2006 .

[25]  Ligang Zheng,et al.  Quantification of chlorine and alkali emissions from fluid bed combustion of coal by equilibrium calculations , 2003 .

[26]  Zhenyu Liu,et al.  The fate of fluorine and chlorine during thermal treatment of coals. , 2006, Environmental science & technology.

[27]  G. Eriksson,et al.  ChemSage—A computer program for the calculation of complex chemical equilibria , 1990 .

[28]  Helmut Lindner,et al.  Physik für Ingenieure , 1989 .

[29]  G. Flamant,et al.  Volatility and chemistry of trace elements in a coal combustor , 2001 .

[30]  A. Attar.  Chemistry, thermodynamics and kinetics of reactions of sulphur in coal-gas reactions: A review , 1978 .

[31]  D. Pavone,et al.  Hot Fuel Gas Cleaning in IGCC at Gasification Temperature , 2009 .

[32]  Thomas A. Milne,et al.  Direct mass-spectrometric studies of the pyrolysis of carbonaceous fuels: I. A flame-pyrolysis molecular-beam sampling technique , 1983 .

[33]  P. Schenck,et al.  Development and application of very high temperature mass spectrometry. Vapor pressure determinations over liquid refractories , 2000 .