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Show OH* Imaging in Large Industrial Oxy-Fuel Flames with Flue Gas Recirculation Chendhil Periasamy, Vijaykant Sadasivuni, Ken Kaiser, Scott Liedel and Remi Tsiava l DRTC-CRCD l R&D-Combustion PUBLIC VERSION 2012 AFRC Annual Meeting University of Utah, Salt Lake City, Utah September 5 - 7, 2012 Overview ■ Background ■ Objectives ■ Experimental Setup Air Liquide, world leader in gases for industry, health 2012 Research & Development and the environment PUBLIC VERSION 2 ■ Results ■ Summary and Conclusions Background PUBLIC VERSION Background ■ Oxy-fuel process with flue gas recirculation Flue Gas Capture Fuel and Treatment CO2 capture/ sequestration Flue Gas Recirculation Oxygen 2012 Research & Development Air Liquide, world leader in gases for industry, health and the environment PUBLIC VERSION 4 ■ Key challenges in combustion Flame stability Control of heat flux distributions Optimization of pollutant emission levels Background ■ Role of OH radical in flames Locations of reaction zone ■ OH Imaging LIF/PLIF Chemiluminescence Biofuel Flames, Periasamy et al. (2008) SME CME Air Liquide, world leader in gases for industry, health 2012 Research & Development and the environment PUBLIC VERSION 5 ■ Challenges in OH Imaging Laboratory-scale flames vs industrial flames ■ Objectives of the present study To study OH* chemiluminescence in 2-4 MW natural gas-fired oxy-burner with flue gas recirculation Large-scale oxy flame, Farzan et al. (2008) Experimental Test Facility ■ Air Liquide Delaware Research and Technology Center ■ Experiments carried out at Outdoor Combustion Test Platform ■ Burner operations up to 6 MW with Air Liquide, world leader in gases for industry, health 2012 Research & Development and the environment PUBLIC VERSION 6 closed-loop heat extraction ■ Flue gas capture, treatment and recirculation ■ Flexible fuel options with full oxy to oxy-enrichment tests Instrumentation Setup BURNER Fuel Oxygen RFG Test Chamber Flue Gas X Y Air Liquide, world leader in gases for industry, health 2012 Research & Development and the environment PUBLIC VERSION 7 ICCD Camera Spectrometer Filters Data Acquisition FGR Ratio = Y X Experimental Test Conditions Parameter Value Burner power tested 2 MW 6.8 MMBTU/hr Natural gas flow rate 6800 SCFH Oxygen flow rate 15400 SCFH Flue gas temperature at test chamber exit 1600 - 1800 F Heat load 0.8 - 1.2 MW Air Liquide, world leader in gases for industry, health 2012 Research & Development and the environment PUBLIC VERSION 8 Flue gas dry O2 2-6% Under FGR Conditions: FGR Ratio 4.5 Flue gas burner inlet temperature 220 F Results PUBLIC VERSION Visible Flame Images Air Liquide, world leader in gases for industry, health 2012 Research & Development and the environment PUBLIC VERSION 10 ■ Easy visualization of flame stability and flame attachment ■ Quick assessment of burner and flame shape ■ No flue gas recirculation applied ICCD Images (No UV Filter) - 2 MW Air Liquide, world leader in gases for industry, health 2012 Research & Development and the environment PUBLIC VERSION 11 ■ High-speed images of near-burner zone flame ■ Flame shape depends on: Burner design Extent of flue gas recirculation Without FGR With FGR OH* Images - 2 MW Air Liquide, world leader in gases for industry, health 2012 Research & Development and the environment PUBLIC VERSION 12 ■ Strong OH signals in No FGR conditions Around the boundary of fuel and oxidizer stream Indicating less penetration ■ With FGR, OH appeared distributed more within flame More mixing due to FGR Without FGR With FGR Flame Emission Spectra Source: Von Drasek et al. (1997) Air Liquide, world leader in gases for industry, health 2012 Research & Development and the environment PUBLIC VERSION 13 ■ Typical oxy-fuel flame emission spectrum for a 1.7 MMBtu/hr flame ■ Dependence of OH spectrum on burner stoichiometry also studied Source: Von Drasek et al. (1997) Flame Emission Spectra Without FGR With FGR Air Liquide, world leader in gases for industry, health 2012 Research & Development and the environment PUBLIC VERSION 14 ■ Stronger intensity observed (arbitrary units) with no FGR ■ Generally lower signal intensity observed with FGR mode Summary and Conclusions ■ Studied OH* in large industrial oxy-fuel flames with and without flue gas recirculation ■ Captured flame emission spectra ■ Summary of results: Air Liquide, world leader in gases for industry, health 2012 Research & Development and the environment PUBLIC VERSION 15 Without FGR With FGR Reaction zone Around the boundary of fuel and oxygen streams Deep penetration Mixing Less Strong Signal intensity Strong Weaker, possibly due to CO2 dilution Thank you for your attention PUBLIC VERSION |