为了实现煤粉高效燃烧和低NOx排放，将中心给粉旋流燃烧器与燃烬风技术相结合，形成多次分级中心给粉旋流燃烧技术。阐述多次分级中心给粉旋流煤粉燃烧技术原理和特点，并指出该技术不仅可以大幅降低NOx排放，同时还具有燃烧效率高、防止结渣和高温腐蚀的优点，并通过实验室试验和工业试验验证该技术的原理。在实验室和实际锅炉上，采用飘带示踪法对不同燃烬风率和外二次风叶片角度下的空气动力场进行测量。试验表明，该燃烧器可以在燃烬风率为25%时可以形成稳定的中心回流区，回流区随着外二次风叶片角度减小而增大。采用三维激光多普勒动态粒子分析仪对采用多次分级技术条件下中心给粉旋流燃烧器出口气固流动特性进行测量。试验表明，颗粒相对数密度峰值出现位置靠近燃烧器中心位置。在一台600 MW机组锅炉上进行热态试验。试验表明，煤粉在距离喷口约为0.1 m位置着火，具有较强的稳燃能力。同时，介绍该技术的应用情况。

The combination of centrally fuel rich swirl burners with over fire air technology formed a centrally fuel rich swirl burner with multi-stage combustion technology for getting higher efficiency and controlling NOx emission. The theory and characteristics of this technology is introduced and analyzed. This technology owns the following characters：Low NOx emission, high combustion efficiency, slagging resistance and high temperature corrosion resistance. Laboratory and Industrial experiments and tested the theory. Single-phase cold flow air experiments on a centrally fuel-rich swirl burner are carried out to investigate the influence of the over fire air ratios and the outer secondary air angle on the flow characteristics in the laboratory and real boiler. The results show that a stable central recirculation zone is formed when an over fire air ratio of 25% and the size of the zone increase with the angle decreasing. A three-component particle-dynamics anemometer is used to measure flow characteristics in the near-burner region in the laboratory. The result show that the peak value of the relative particle number locates the burner centerline. Measurements are taken for a 600 MW wall-fired pulverized-coal utility boiler that is retrofitted with centrally fuel rich swirl coal combustion burners and multi-stage combustion technology. The result show that the burner has good performance when a over fire ratio of 25%. Some applications are given.