%0 Generic %1 sharpsuperheater %A Sharp, W.B.A %A Singbeil, Douglas L. %A Keiser, James R. %D 2012 %I NACE International %K biomass %T Superheater Corrosion Produced By Biomass Fuels %X ABSTRACT: About 90% of the world''s bioenergy is produced by burning renewable biomass fuels. Low-cost biomass fuels such as agricultural wastes typically contain more alkali metals and chlorine than conventional fuels. Although the efficiency of a boiler’s steam cycle can be increased by raising its maximum steam temperature, alkali metals and chlorine released in biofuel boilers cause accelerated corrosion and fouling at high superheater steam temperatures. Most alloys that resist high temperature corrosion protect themselves with a surface layer of Cr2O3. However, this Cr2O3 can be fluxed away by reactions that form alkali chromates or volatilized as chromic acid. This paper reviews recent research on superheater corrosion mechanisms and superheater alloy performance in biomass boilers firing black liquor, biomass fuels, blends of biomass with fossil fuels and municipal waste. INTRODUCTIONIndustrial boilers could, in principle, fire renewable biomass fuels instead of fossil fuels like natural gas, coal, and fuel oil. However, biomass fuels often contain elements such as chlorine, potassium, sodium and sulfur that deposit in ash on the superheater tubes that heat the steam to its maximum temperature. Because many components of these ash deposits and the surrounding flue gases are corrosive, operators have historically limited the temperatures of biomass boiler superheater tubes substantially below those of fossil-fuel-fired boilers to avoid accelerated corrosion. Unfortunately, lower steam temperatures reduce the energy derived from the fuel and produce boiler efficiencies far below those of advanced fossil-fuel-fired boilers. A project has been funded under DOE Award DE-FC36- 04GO17884 to investigate corrosion mitigation strategies that could improve the efficiency of biomassfueled boilers - both to increase the use of renewable energy and to reduce the USA’s dependence on imported fossil fuels. A previous report1 reviewed improvements in biomass boiler design and operation developed in European countries that signed the 1997 Kyoto Protocol.

@conference{sharpsuperheater, abstract = {ABSTRACT: About 90% of the world''s bioenergy is produced by burning renewable biomass fuels. Low-cost biomass fuels such as agricultural wastes typically contain more alkali metals and chlorine than conventional fuels. Although the efficiency of a boiler’s steam cycle can be increased by raising its maximum steam temperature, alkali metals and chlorine released in biofuel boilers cause accelerated corrosion and fouling at high superheater steam temperatures. Most alloys that resist high temperature corrosion protect themselves with a surface layer of Cr2O3. However, this Cr2O3 can be fluxed away by reactions that form alkali chromates or volatilized as chromic acid. This paper reviews recent research on superheater corrosion mechanisms and superheater alloy performance in biomass boilers firing black liquor, biomass fuels, blends of biomass with fossil fuels and municipal waste. INTRODUCTIONIndustrial boilers could, in principle, fire renewable biomass fuels instead of fossil fuels like natural gas, coal, and fuel oil. However, biomass fuels often contain elements such as chlorine, potassium, sodium and sulfur that deposit in ash on the superheater tubes that heat the steam to its maximum temperature. Because many components of these ash deposits and the surrounding flue gases are corrosive, operators have historically limited the temperatures of biomass boiler superheater tubes substantially below those of fossil-fuel-fired boilers to avoid accelerated corrosion. Unfortunately, lower steam temperatures reduce the energy derived from the fuel and produce boiler efficiencies far below those of advanced fossil-fuel-fired boilers. A project has been funded under DOE Award DE-FC36- 04GO17884 to investigate corrosion mitigation strategies that could improve the efficiency of biomassfueled boilers - both to increase the use of renewable energy and to reduce the USA’s dependence on imported fossil fuels. A previous report1 reviewed improvements in biomass boiler design and operation developed in European countries that signed the 1997 Kyoto Protocol.}, added-at = {2014-06-26T14:52:02.000+0200}, author = {Sharp, W.B.A and Singbeil, Douglas L. and Keiser, James R.}, biburl = {https://www.bibsonomy.org/bibtex/22f602594a29b3536e19a0caf89972a61/docal}, interhash = {19f95d1306362a1c43f6bd77e916c193}, intrahash = {2f602594a29b3536e19a0caf89972a61}, keywords = {biomass}, publisher = {NACE International}, timestamp = {2014-06-26T14:52:02.000+0200}, title = {Superheater Corrosion Produced By Biomass Fuels}, year = 2012 }