This paper reports the oxy-fuel combustion characteristics in a pilot-scale furnace with a bituminous coal. After discussing the design principles of oxy-fuel burners in detail, a swirling low-NO_x burner system is specially designed to achieve the compatible combustion of air-fuel combustion and oxy-fuel combustion. The initial O₂ concentrations vary between 22 and 30% by volume in the oxy-fuel combustion. A reliable transition process is performed between different combustion modes. Measurements of flame images, burnout rate, heat transfer, and pollution emission are carried out. The results show that compatible and stable combustion with low NO_x emissions is achieved in different combustion modes. A high time-averaged CO₂ concentration of 81.5% by volume is achieved in the dry flue gas. In this test facility, compared to air-fuel combustion, the averaged burnout rate of pulverized coal slightly increases (∼97%) despite the decrease in flame temperature. There is an optimal initial O₂ concentration between 26 and 30% by volume, which can achieve a similar heat transfer process with air-fuel combustion. By using a low-NO_x oxy-fuel burner system and flue gas recycle, NO_x emissions decrease to a level that is 30–50% of that in air-fuel combustion. The oxy-fuel combustion with a low-NO_x oxy-fuel burner system is confirmed for efficiently and cleanly burning pulverized coal.

中文翻译：

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3 MW中试炉内煤粉的氧燃料燃烧特性。

本文报道了在含烟煤的中试炉中的氧燃料燃烧特性。在详细讨论氧-燃料燃烧器的设计原理后，回旋低NO _X燃烧器系统是专门设计的，以实现空气-燃料燃烧和氧化燃料燃烧的燃烧兼容。在氧气-燃料燃烧中，初始O ₂浓度在22至30％（体积）之间变化。在不同的燃烧模式之间执行可靠的过渡过程。进行火焰图像，燃尽率，热传递和污染排放的测量。结果显示具有低NO其兼容且稳定的燃烧_X排放量不同的燃烧模式得以实现。高平均时间的CO ₂在干烟道气中，浓度达到了81.5％（体积）。在该试验设备中，尽管火焰温度降低，但与空气燃料燃烧相比，煤粉的平均燃尽率略有提高（〜97％）。最佳初始O ₂浓度在26％至30％（体积）之间，可以实现与空气-燃料燃烧相似的传热过程。通过使用低NO _X的氧-燃料燃烧器系统和烟道气再循环，NO _X的排放量减少到是在空气-燃料燃烧30％-50％的水平。使用低NO _x的氧气燃料燃烧器系统进行的氧气燃料燃烧可有效而清洁地燃烧煤粉。