Open AccessThe Effects of the Size and Location of the Recirculation Windows of Combustion Chambers in a Coke Oven on Emissions of NO and Unburnt Fuels by CFD Numerical Simulation
Author(s) -
Cao Yinping,
Zhengang Du,
Zhen Hu,
Shuangling Jin,
Wangzhao Lu,
Rui Zhang
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/964/1/012006
Subject(s) - combustion , flue gas , flux (metallurgy) , heat flux , materials science , nuclear engineering , waste management , chemistry , mechanics , heat transfer , metallurgy , engineering , physics , organic chemistry
NO x emission from combustion chambers of coke ovens is receiving renewed attention in recent years in China. Combustion process optimization and post combustion treatments are used to reduce NO x emission. In this paper, the effects of size and location of recirculation windows in the heating flues of combustion chambers in a coke oven from Baoshan Iron & Steel Co., Ltd. on emissions of NO and unburnt fuels were investigated by CFD numerical simulation, targeting for redesign of recirculation windows. Results indicate that with increasing the window size, the amount of recycled flue gases increases, maximum flame temperature decreases and temperature uniformity is improved, leading to a reduction of NO emission. The emission of unburnt fuels increases with the window size at higher heat flux, but this is less obvious at lower heat flux. With moving the windows towards inlets of fuels and air, the average temperatures increase slightly, maximum flame temperature and temperature uniformity keep unchanged, the emission of unburnt fuels decreases apparently, the NO emission increases slightly at lower heat flux, but keeps unchanged at higher heat flux. The unburnt fuel emission is dominated by the average temperature while NO emission by both the average temperature and temperature uniformity. The effect of the window size on NO emission is more apparent than that of the location of the windows while the latter is more obvious than the former to reduce the unburnt fuel emission.