Browse > Article
http://dx.doi.org/10.3795/KSME-B.2016.40.10.637

Characteristics of UBC and NOx Emission in Air Staging Combustion  

Kim, Jeong Woo (Dept. of Mechanical Engineering, Pusan Nat'l Univ.)
Lim, Ho (Dept. of Mechanical Engineering, Pusan Nat'l Univ.)
Go, Young Gun (System Engineering Team, Corporate R&D Institute, Doosan Heavy Industries and Construction)
Jeon, Chung Hwan (Dept. of Mechanical Engineering, Pusan Nat'l Univ.)
Publication Information
Transactions of the Korean Society of Mechanical Engineers B / v.40, no.10, 2016 , pp. 637-644 More about this Journal
Abstract
The purpose of this study is to understand the characteristics of unburned carbon (UBC) and NOx emissions for pulverized coal when air staging combustion is applied. A two-staged drop tube furnace capable of applying air staging combustion was designed and installed. The combustion of sub-bituminous (Tanito) has been investigated. UBC and the NOx concentration were measured under various temperatures and stoichiometric ratios in unstaged and staged combustion. As a result, UBC decreased and the NOx concentration increased with an increase in stoichiometric ratio and temperature. In particular, the NOx reduction mechanism was activated when the temperature in the fuel rich zone increased. Both UBC and the NOx concentration decreased as the temperature increased in the fuel rich zone. A high NOx reduction effect was obtained, compared to the UBC increase, when the air staging technique was applied.
Keywords
NOx; NOx Reduction; Air-fuel Staging; Pulverized Coal Combustion; Staged Combustion; Unburned Carbon;
Citations & Related Records
Times Cited By KSCI : 4  (Citation Analysis)
연도 인용수 순위
1 Kang, K. T., Song, J. H., Yoon, M. J., Lee, B. H., Kim, S. M., Chang, Y. J. and Jeon, C. H, 2009, "A Numerical Study on the Effects of SOFA on NOx Emission Reduction in 500 MW Class Subbituminous Coal-Fired Boiler," Trans. Korean Soc. Mech. Eng. B, Vol. 33, No. 11, pp. 858-868.   DOI
2 Miller, J. A. and Bowman, C. T., 1989, "Mechanism and Modeling of Nitrogen Chemistry in Combustion," Progress in Energy and Combustion Science, Vol. 15, No. 4, pp. 287-338.   DOI
3 Zel'dovich, Y. B., 1946, "The Oxidation of Nitrogen in Combustion Explosions," Acta Physicochimica U.S.S.R. Vol. 21, pp. 577-628.
4 Fenimore, C. P., "Formation of Nitric Oxide in Premixed Hydrocarbon Flames," Symposium (International) on Combustion, Vol. 13, pp. 373-380.
5 Luis I. Diez, Cristobal, C. and Javier, P., 2008, "Numerical Investigation of NOx Emissions from a Tangentially-fired Boiler under Conventional and Over fire Air Operation," Fuel, Vol. 87, pp. 1259-1269.   DOI
6 Flower, WL., Hanson, RK. and Kruger, CH., 1974, "Investigation of Nitric Oxide Decomposition in the Temperature Range 2500-4100K," Fifteenth Symposium (International) on Combustion, Pittsburgh, The Combustion Institute, pp. 823-832.
7 Monat JP., Hanson RK. and Kruger CH., 1978, "Shock Tube Determination of The Rate Coefficient for The Reaction O + $N_2$ ${\rightarrow}$ N + NO," Seventeenth Symposium (International) on Combustion, Pittsburgh, The Combustion Institute, pp. 543-552.
8 Taniguchi, M., Kamikawa, Y., Tatsumi, T. and Yamamoto, K., 2011. "Staged Combustion Properties for Pulverized Coals at High Temperature," Combustion and Flame, Vol. 158, No. 11, pp. 2261-2271.   DOI
9 Taniguchi, M., Kamikawa, Y., Okazaki, T., Yamamoto, K. and Orita, H., 2010, "A Role of Hydrocarbon Reaction for NOx Formation and Reduction in Fuel-rich Pulverized Coal Combustion," Combustion and Flame Vol. 157, No. 8, pp. 1456-1466.   DOI
10 Houshfar, E., Skreiberg, O., Lovas, T., Todorovic, D. and Sorum, L., 2011, "Effect of Excess Air Ratio and Temperature on NOx Emission from Grate Combustion of Biomass in the Staged Air Combustion Scenario," Energy & Fuels, Vol. 25, No. 10, pp. 4643-4654.   DOI
11 Kim, S. I., Lee, B. H., An, K. J., Kim, M. C., Kim, S. M. and Jeon, C. H, 2014, "Effect of Ash Content on Unburned Carbon and NOx Emission in a Drop Tube Furnace," Trans. Korean Soc. Mech. Eng. B, Vol. 38, pp. 963-969.   DOI
12 Kim, S. I., Lee, B. H., Lim, H., Yu, D. Y., Lee, S. H. and Jeon, C. H, 2012, "Char Oxidation Characteristics of Ashless Coal in Drop Tube Furnace" Trans. Korean Soc. Mech. Eng. B, Vol. 36 No. 7, pp. 675-681.   DOI
13 Jeon, C.-H., Kim, S.-G., Song, J.-H., Kim, G.-B., Lee, B.-H. and Lee, C.-S., 2013, "Powder Phase Fuel Supply Apparatus," F23K 1/00 B01F 5/00, Jan. 10.
14 Lee, B.-H., Song, J.-H., Kang, K.-T., Chang Y.-J. and Jeon, C.-H., 2009, "Determination of Char Oxidation Rates with Different Analytical Methods," Trans. Korean Soc. Mech. Eng. B, Vol. 33, No. 11, pp. 876-885.   DOI
15 Choi, C. R. and Kim, C. N., 2009, "Numerical Investigation on the Flow, Combustion and NOx Emission Characteristics in a 500 MWe Tangentially Fired Pulverized-coal Boiler," Fuel Vol. 88, No. 9, pp. 1720-1731.   DOI
16 Ministry of Environment, 2014, Classification of Air Pollutant Emission/discharge Facility and Interpretation of Emission Standard, pp. 25-35.