为适应某电厂360MW机组贫煤锅炉安全高效燃用高挥发分煤种的要求，本文在煤质分析和热重实验基础上分析了拟燃用煤种的着火、燃尽和结渣等燃烧特性，通过对机组制粉、燃烧、风烟等主要系统设备的燃料适应性研究，提出了“钢球磨煤机炉烟干燥-乏气/热风复合送粉技术”改造方案。热态试验结果表明，技术改造后机组系统设备可依据燃用煤质实现灵活切换，显著提升了机组燃料适应性。在全烧烟煤及烟煤/褐煤煤种的不同负荷工况下，机组各系统运行安全稳定，各运行参数均满足设计要求，锅炉热效率达到92%以上，炉膛出口NOx浓度大幅下降，实现了机组40%负荷下稳燃要求，技术改造取得了显著的安全、经济、环保效果，研究成果对我国大型贫煤锅炉燃用高挥发煤种的技术应用具有重要的理论借鉴和工程参考意义。

In order to meet the requirements of safe and efficient combustion of high volatile coal in a 360 MW unit lean coal-fired boiler, the ignition, burnout and slagging characteristics of the coal were studied on the basis of composition analysis and thermogravimetric experiment. Through the research on the fuel adaptabilities of main systems such as coal pulverizing system, combustion system, air and flue gas system, the transformation scheme was put forward, which is conducted with a ball mill using flue gas drying, exhaust-air and hot air composite powder feeding technology. The results are as follows:(1) the system equipment of the unit can be flexibly switched according to the coal quality, which significantly improves the fuel adaptability; (2) all systems of the unit operate safely under different conditions, and all operating parameters meet the design requirements; (3)the thermal efficiency of the boiler is more than 92 %, the NOx concentration at the furnace outlet is greatly reduced, and the requirement of stable combustion under 40 % load of the unit is realized. In a word, this technical transformation has achieved remarkable effect on safety, economic and environmental protection. And it also provides important theoretical and engineering significance for the technical application of high-volatile coal burning in large lean coal-fired boiler in China.

TK223