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http://dx.doi.org/10.3795/KSME-B.2010.34.6.587

Numerical Study of the Optimization of Combustion and Emission Characteristics of Air-Staged Combustion in a Pulverized Coal-Fired Boiler  

Yoon, Min-Ji (School of Mechanical Engineering, Pusan Nat'l Univ.)
Lee, Byoung-Hwa (School of Mechanical Engineering, Pusan Nat'l Univ.)
Song, Ju-Hun (School of Mechanical Engineering, RIMT, PC, Pusan Nat'l Univ.)
Kim, Gyu-Bo (Pusan Clean Coal Center(PC), Pusan Nat'l Univ.)
Chang, Young-June (School of Mechanical Engineering, RIMT, PC, Pusan Nat'l Univ.)
Jeon, Chung-Hwan (School of Mechanical Engineering, RIMT, PC, Pusan Nat'l Univ.)
Publication Information
Transactions of the Korean Society of Mechanical Engineers B / v.34, no.6, 2010 , pp. 587-597 More about this Journal
Abstract
Air-staged combustion is known to be one of the techniques of NOx reduction. The objective of this study is to determine the optimal ratio of air flow distributed for CCOFA and SOFA; at this optimal ratio, the combustion and exhaust emission characteristics of a pulverized coal-fired boiler are maintained at a satisfactory level. A numerical investigation was performed at various airflow ratios of 16.7/83.3%, 25/75%, 50/50%, 75/25%, and 83.3/16.7%. An inert gas was considered as a substitute for air to isolate the effects of the cooling process and chemical reaction on NOx reduction; during NOx reduction in air-staged combustion, both the effects typically occur simultaneously. The results of our study show that the optimum condition, under which the maximum NOx reduction and highest boiler efficiency can be obtained, corresponds to the equal splitting of the over-fire air between CCOFA and SOFA.
Keywords
Air Staged Combustion; NOx Emission; Close Coupled Over Fire Air(CCOFA); Separated Over Fire Air(SOFA);
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
Times Cited By SCOPUS : 0
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