The oxy-fuel combustion of blended coal characteristics and rule were studied in the 2500 t/d precalciner cement kiln with a four-channel burner via experiment and simulation, and the reliability of simulation results was verified by experiments. The results show that as the oxygen mole fraction of primary air rises, the combustion temperature and heat transfer rate both increase while the coal ignition temperature gradually reduces. The numerical calculation indicates that the blended coal combustion characteristics in the precalciner kiln are considerably improved using the technology of oxy-fuel combustion. Besides, the blending ratio of anthracite suitable for the kiln greatly increases in the oxy-mode combustion. Compared with the traditional air-mode combustion, the average flame temperature and char burnout ratio increase by 97 K and 5.09%, respectively, when the oxygen mole fraction of primary air is 27%. Meanwhile, even at the anthracite-blended ratio of up to 60%, the efficient and stable combustion are still obtained, and the flame property including temperature and shape can meet the requirements of clinker calcinations.%以2500 t/d带四通道煤粉燃烧器的水泥分解窑为研究对象,通过理论分析和数值仿真方法,对分解窑内混煤富氧燃烧特性和燃烧规律进行研究,并通过实验验证仿真计算结果的可靠性.研究结果表明:随着燃烧器一次风O2摩尔分数增加,煤粉着火温度逐渐降低,燃烧温度、窑内传热速率逐渐增加;应用富氧燃烧技术能显著改善分解窑混煤燃烧特性,大幅提高无烟煤掺混比;与一般空气助燃相比,当一次风O2摩尔分数提高到27%时,火焰平均温度提高97 K,焦炭燃尽率提高5.09%,在此O2摩尔分数下,无烟煤掺比增至60%时,混煤仍能高效稳定燃烧,火焰温度和形状仍能满足熟料煅烧要求.
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