A thermodynamic study of hot syngas impurities in steel reheating furnaces – Corrosion and interaction with oxide scales

Environmental concerns lead industries to implement gasified biomass (syngas) as a promising fuel in steel reheating furnaces. The impurities of syngas as well as a combination with iron oxide scale form complex mixtures with low melting points, and might cause corrosion on steel slabs. In this paper, the effects of syngas impurities are thermodynamically investigated, when scale formation on the steel slabs surface simultaneously takes place. A steel reheating furnace can be divided into preheating, heating, and soaking zones where the temperature of a steel slab changes respectively. Therefore, the thermodynamic calculation is performed at different temperatures to predict the fate of impurities. Then, the stable species are connected with respective zones in a reheating furnace. It is concluded that reactions due to alkali compounds, chloride, and particulate matter could take place on steel slabs. In the low temperature range, interaction of sodium chloride occured with pure iron prior to scale formation. Then, at high temperature the reactions of impurities are notable with iron oxides due to scale growing. Furthermore, the multicomponent reactions with syngas impurities showed that most of alkali contents evaporate at first stages, and only small amounts of them remain in slag at high temperature.

[1]  Michael Müller,et al.  Influence of the particle size on the release of inorganic trace elements during gasification of biomass pellets , 2013 .

[2]  P. Raman,et al.  A dual fired downdraft gasifier system to produce cleaner gas for power generation: Design, development and performance analysis , 2013 .

[3]  和久 茂,et al.  E.M.Levin, H.F.McMurdie: Phase Diagrams for Ceramists: The American Ceramic Society. 4055N. High St., Columbus 14, Ohio. Part I. 1956, 286頁, 20×27.5cm, $10, Part II, 1959, 153頁, 20×27.5cm, $8. , 1961 .

[4]  H. Spliethoff,et al.  Continuous in situ measurements of alkali species in the gasification of biomass , 2013 .

[5]  Gui-Bing Hong,et al.  The case study of furnace use and energy conservation in iron and steel industry , 2010 .

[6]  Kj Krzysztof Ptasinski,et al.  More efficient biomass gasification via torrefaction , 2006 .

[7]  L. L. Oden,et al.  The behavior of inorganic material in biomass-fired power boilers: Field and laboratory experiences , 1998 .

[8]  C. Bertrand,et al.  Thermodynamic equilibrium calculations of the volatilization and condensation of inorganics during wood gasification , 2013 .

[9]  Wei Hsin Chen,et al.  A comparison of gasification phenomena among raw biomass, torrefied biomass and coal in an entrained-flow reactor , 2013 .

[10]  Brian Elmegaard,et al.  Decentralized combined heat and power production by two-stage biomass gasification and solid oxide fuel cells , 2013 .

[11]  P. V. Aravind,et al.  Evaluation of high temperature gas cleaning options for biomass gasification product gas for Solid Oxide Fuel Cells , 2012 .

[12]  Gunnar Eriksson,et al.  FactSage thermochemical software and databases , 2002 .

[13]  Madhu Ranjan,et al.  Influence of Alumina on Iron Ore Sinter Properties and Productivity in the Conventional and Selective Granulation Sintering Process , 2009 .

[14]  Daejun Chang,et al.  Efficiency analysis of radiative slab heating in a walking-beam-type reheating furnace , 2011 .

[16]  Vladan Karamarkovic,et al.  Energy and exergy analysis of biomass gasification at different temperatures , 2010 .

[17]  Larry L. Baxter,et al.  The implications of chlorine-associated corrosion on the operation of biomass-fired boilers , 2000 .

[18]  M. Thring World Energy Outlook , 1977 .

[19]  Fang He,et al.  Synthesis gas production from biomass gasification using steam coupling with natural hematite as oxygen carrier. , 2013 .

[20]  E. Reese,et al.  The effects of chlorides, hydrogen chloride, and sulfur dioxide in the oxidation of steels below deposits , 1995 .

[21]  Y. Niu,et al.  Accelerated corrosion of pure Fe, Ni, Cr and several Fe-based alloys induced by ZnCl2–KCl at 450 °C in oxidizing environment , 2003 .

[22]  Kim Dam-Johansen,et al.  Lab-Scale Investigations of High-Temperature Corrosion Phenomena in Straw-Fired Boilers , 1999 .

[23]  Hrycko Piotr,et al.  Biomass gasification and Polish coal-fired boilers for process of reburning in small boilers , 2013 .

[24]  Michael Müller,et al.  Chemical Hot Gas Cleaning Concept for the "CHRISGAS" Process , 2011 .

[25]  Robert C. Brown,et al.  A review of cleaning technologies for biomass-derived syngas , 2013 .

[26]  M. V. Gil,et al.  Gasification of rice straw in a fluidized-bed gasifier for syngas application in close-coupled boiler-gasifier systems. , 2012, Bioresource technology.

[27]  Uwe Schnell,et al.  Behaviour of Gaseous Chlorine and Alkali Metals During Biomass Thermal Utilisation , 2005 .

[28]  Wahab Mojtahedi,et al.  Fate of alkali and trace metals in biomass gasification , 1998 .

[29]  Fredrik Berntsson,et al.  Estimation of the transient surface temperature and heat flux of a steel slab using an inverse method , 2007 .

[30]  J. Svensson,et al.  The influence of small amounts of KCl(s) on the high temperature corrosion of a Fe‐2.25Cr‐1Mo steel at 400 and 500°C , 2011 .

[31]  David Baxter,et al.  Co-firing of biomass waste-derived syngas in coal power boiler , 2008 .

[32]  C. M. Kinoshita,et al.  An Experimental Investigation of Alkali Removal from Biomass Producer Gas Using a Fixed Bed of Solid Sorbent , 2001 .