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Pure Oxy-Fuel Circulating Fluidized Bed Combustion by Controlling Adiabatic Flame Temperature Using Fuel Staging


Affiliations
1 Indian Institute of Technology, Bombay, India
 

In the present study, a new method is proposed for temperature controlling by combustion staging. Two combustion stages can be used with two stages of fuel feeding. A high stoichiometric ratio (SR) λ > 1 is used at the first stage to mitigate adiabatic flame temperature (AFT) in case of high O2% in the oxidant. For validation, a series of experiments are conducted using mini-CFB (circulating fluidized bed), and an oxidant of 100% O2 concentration is used with three SR ratios, i.e. λ = 1.25, 2.0 and 3.0. The resulting average temperatures along the riser for biomass are 1031°C, 950°C and 798°C; and for coal 1129°C, 1051°C and 961°C respectively. The controlling of AFT with pure oxy-fuel combustion eliminates the recycled flue gas in oxy-fuel CFB combustion and flue gas recirculation section; this simplifies design, fabrication and installing-operating costs of the power plants. Familiarizing this concept can accelerate adapting oxy-fuel combustion in CFB power plants for carbon capturing and sequestration. This study can help commercialize the third generation of oxy-fuel CFB combustion with zero RFG. Finally, the concept of controlling AFT by SR is validated experimentally.

Keywords

Adiabatic Flame Temperature, Carbon Capturing and Sequestration, Circulating Fluidized Bed, Oxyfuel Combustion.
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  • Ambrosio, S. and Ferrari, A., Effects of exhaust gas recirculation in diesel engines featuring late PCCI type combustion strategies. Energy Convers. Manage., 2015, 105, 1269–1280.

  • Cung, K., Moiz, A., Johnson, J., Lee, S.-Y., Kweon, C.-B. and Montanaro, A., Spray–combustion interaction mechanism of multipleinjection under diesel engine conditions. Proc. Combust. Inst., 2015, 35, 3061–3068.

  • Finesso, R. and Spessa, E., Ignition delay prediction of multiple injections in diesel engines. Fuel, 2014, 119, 170–190.

  • Hiwase, S. D., Moorthy, S., Prasad, H., Dumpa, M. and Metkar, R. M., Multidimensional modeling of direct injection diesel engine with split multiple stage fuel injections. Procedia Eng., 2013, 51, 670–675.

  • Wu, Z., Yu, X., Fu, L., Deng, J., Hu, Z. and Li, L., A high efficiency oxyfuel internal combustion engine cycle with water direct injection for waste heat recovery. Energy, 2014, 70, 110–120.

  • Bolea, I., Romeo, L. M. and Pallarès, D., Heat transfer in the external heat exchanger of oxy-fuel fluidized bed boilers. Appl. Therm. Eng., 2014, 66, 75–83.

  • Seddighi, S., Pallarès, D., Normann, F. and Johnsson, F., Heat transfer in a 4-MWth circulating fluidized bed furnace operated under oxy-fired and air-fired conditions: modeling and measurements. Int. J. Greenhouse Gas Control, 2015, 37, 264–273.

  • Ochs, T., Oryshchyn, D., Woodside, R. and Summers, C., Results of initial operation of the Jupiter Oxygen Corporation oxy-fuel 15 MWth burner test facility. Energy Procedia, 2009, 1, 511–518.

  • Schoenfield, M., Jupiter oxygen. In IEA GHG 1st Oxyfuel Combustion Conference, Cottbus, Germany, 2009, pp. 1–45.

  • Salzmann, R. and Nussbaumer, T., Fuel staging for NOx reduction in biomass combustion: experiments and modeling. Energy Fuels, 2001, 15, 575–582.

  • Nussbaumer, T., Combustion and co-combustion of biomass: fundamentals, technologies, and primary measures for emission reduction. Energy Fuels, 2003, 17, 1510–1521.

  • ya Nsakala, N. et al., Oxygen-fired circulating fluidized bed boilers for greenhouse gas emissions control and other applications. In Third Annual Conference on Carbon Capture and Sequestration, Alexandria, Virginia, USA, 2004, pp. 1–21.

  • US Department of Energy, Improving Process Heating System Performance: A Sourcebook for Industry, Berkeley, California, 2007.

  • Seddighi, S., Pallarès, D., Normann, F. and Johnsson, F., Heat extraction from a utility-scale oxy-fuel-fired CFB boiler. Chem. Eng. Sci., 2015, 130, 144–150.

  • Lupion, M., Alvarez, I., Otero, P., Kuivalainen, R., Hotta, A. and Hack, H., 30 MWth CIUDEN oxy-CFB boiler – first experiences. Energy Procedia, 2013, 37, 6179–6188.

  • Liljedahl, G., Turek, D., ya Nsakala, N., Mohn, N. and Fout, T., Alstom’s oxygen-fired CFB technology development status for CO2 mitigation. In 31st International Technical Conference on Coal Utilization and Fuel Systems, Sand Key Island, Florida, United States, 21 to 26 May 2006.

  • Eddings, E. G. and Okerlund, R., Pilot scale evaluation of oxycoal firing in circulating-fluidized bed and pulverized coal-fired test facilities. In 1st Oxyfuel Combustion Conference, Cottbus, Germany, 2009.

  • Jia, L., Tan, Y. and Anthony, E. J., Emissions of SO2 and NOx during oxy-fuel CFB combustion tests in a mini-circulating fluidized bed combustion reactor. Energy Fuels, 2010, 24, 910–915.

  • Czakiert, T., Sztekler, K., Karski, S., Markiewicz, D. and Nowak, W., Oxy-fuel circulating fluidized bed combustion in a small pilot-scale test rig. Fuel Process. Technol., 2010, 91, 1617–1623.

  • Seddighi, S., Pallarès, D. and Johnsson, F., Assessment of oxyfuel circulating fluidized bed boilers – modeling and experiments in a 5 MW pilot plant 5–7. In 2nd IEA GHG International Oxyfuel Combustion Conference, Queensland, Australia, 2011.

  • Tondl, G., Penthor, S., Wöν, D., Pröll, T., Höltl, W., Rohovec, J. and Hofbauer, H., From oxygen enrichment to oxyfuel combustion. In 63th IEA Fluidized Bed Conversion Meeting, Ponferrada, Spain, 2011.

  • Hack, H. et al., Initial operation of the CIUDEN Oxy-CFB boiler demonstration project. In 11th Annual Carbon Capture, Utilization and Sequestration Conference, Pittsburgh, Pennsylvania, USA, 2012, p. 15.

  • Seddighi, S., Pallarès, K. D., Normann, F. and Johnsson, F., Progress of combustion in an oxy-fuel circulating fluidized-bed furnace: measurements and modeling in a 4 MWth boiler. Energy Fuels, 2013, 27, 6222–6230.

  • Duan, L., Sun, H., Zhao, C., Zhou, W. and Chen, X., Coal combustion characteristics on an oxy-fuel circulating fluidized bed combustor with warm flue gas recycle. Fuel, 2014, 127, 47–51.

  • Li, H., Li, S., Ren, Q., Li, W., Xu, M., Liu, J. Z. and Lu, Q., Experimental results for oxy-fuel combustion with high oxygen concentration in a 1 MWth pilot-scale circulating fluidized bed. Energy Procedia, 2014, 63, 362–371.

  • Tan, L., Li, S., Li, W., Shou, E. and Lu, Q., Effects of oxygen staging and excess oxygen on O2/CO2 combustion with a high oxygen concentration in a circulating fluidized bed. Energy Fuels, 2014, 28, 2069–2075.

  • Kobayashi, H. and Bool, L. E., Direct oxy-coal combustion with minimum or no flue gas recycle. In Oxy-fuel Combustion for Power Generation and Carbon Dioxide (CO2) Capture (ed. Zheng, L.), Woodhead Publishing Limited, Cambridge, UK, 2011, p. 374.

  • US Department of Energy, Energy tips 3 – process heating, industrial heating, 2005.

  • Duan, L., Zhao, C., Zhou, W., Qu, C. and Chen, X., O2/CO2 coal combustion characteristics in a 50 kWth circulating fluidized bed. Int. J. Greenhouse Gas Control, 2011, 5, 770–776.


Abstract Views: 364

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  • Pure Oxy-Fuel Circulating Fluidized Bed Combustion by Controlling Adiabatic Flame Temperature Using Fuel Staging

Abstract Views: 364  |  PDF Views: 117

Authors

Azd Zayoud
Indian Institute of Technology, Bombay, India
P. Mahanta
Indian Institute of Technology, Bombay, India
U. K. Saha
Indian Institute of Technology, Bombay, India

Abstract


In the present study, a new method is proposed for temperature controlling by combustion staging. Two combustion stages can be used with two stages of fuel feeding. A high stoichiometric ratio (SR) λ > 1 is used at the first stage to mitigate adiabatic flame temperature (AFT) in case of high O2% in the oxidant. For validation, a series of experiments are conducted using mini-CFB (circulating fluidized bed), and an oxidant of 100% O2 concentration is used with three SR ratios, i.e. λ = 1.25, 2.0 and 3.0. The resulting average temperatures along the riser for biomass are 1031°C, 950°C and 798°C; and for coal 1129°C, 1051°C and 961°C respectively. The controlling of AFT with pure oxy-fuel combustion eliminates the recycled flue gas in oxy-fuel CFB combustion and flue gas recirculation section; this simplifies design, fabrication and installing-operating costs of the power plants. Familiarizing this concept can accelerate adapting oxy-fuel combustion in CFB power plants for carbon capturing and sequestration. This study can help commercialize the third generation of oxy-fuel CFB combustion with zero RFG. Finally, the concept of controlling AFT by SR is validated experimentally.

Keywords


Adiabatic Flame Temperature, Carbon Capturing and Sequestration, Circulating Fluidized Bed, Oxyfuel Combustion.

References





DOI: https://doi.org/10.18520/cs%2Fv113%2Fi08%2F1560-1567