为满足超低排放标准，某电厂筹建超临界CFB锅炉并在旋风分离器处安装选择性非催化还原（SNCR）脱硝设备。运用CHMKIN软件简化SNCR反应机理，并将简化后的18个化学反应机理和CFD软件结合，对CFB锅炉旋风分离器SNCR脱硝反应过程进行数值模拟，得到超临界CFB锅炉SNCR脱硝特性。结果表明：SNCR的反应温窗范围在850~1 050 ℃间，脱硝率随温度增加先升高而后降低，在950 ℃达到峰值；低温时提高氨氮摩尔比（NSR）对脱硝率影响不大，温度在反应温窗内时，提高NSR可以有效提升脱硝率，但增加NSR到一定程度，增涨会变缓，设置NSR=1.5左右较合理；低温时NH3逃逸量随NSR升高而增加，温度升高，NH3逃逸量逐渐减少，温度大于935 ℃时NH3逃逸量小于10 mg/m3。

In order to meet the ultra low emission standards,a power plant will build supercritical CFB boiler and install SNCR denitrification equipment at the cyclone separator.The CHMKIN software was used to simplify the SNCR reaction mechanism,resulting in 18 chemical reactions,which were then combined with CFD to numerically simulate SNCR denitrification process in the cyclone separator of CFB boiler.The SNCR denitrification characteristics of supercritical CFB boiler were obtained: the window of reaction temperature for SNCR process is in a range of 850~1 050 ℃.The denitrification efficiency increases first and then decreases with the increase of temperature,with the peak at 950℃.At low temperature,improving NSR has little effect on the denitrification efficiency.When the reaction temperature is in the temperature window,improving NSR can effectively enhance the denitrification efficiency.But increasing NSR to a certain extent,denitrification efficiency increases will slow down,so setting NSR around1.5 is more reasonable.At low temperature NH3 slip increases with the increase of NSR,while the NH3 slip decreases gradually as temperature increases.When the temperature is greater than 935 ℃,the NH3 slip is less than 10 mg/m3.

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