掺炉烟系统应用研究

Study on the application of blending flue gas system

为保障330 MW机组锅炉制粉系统的安全运行,通过制粉系统掺入炉烟,将煤粉磨制和输送过程中干燥剂的氧质量分数控制在安全范围内,根除爆燃隐患,保证磨煤机和制粉系统的安全运行,同时可通过降低一次风氧浓度来降低锅炉燃烧氮氧化合物生成,减少喷氨量,缓解预热器堵塞和SCR负荷过重。增加炉膛烟气流量,提高炉膛出口及各段烟气温度,提高预热器入口烟温下移结晶区,有利于吹灰疏堵,提高低负荷下主、再热温度,增加机组的经济性。

In order to ensure the safe operation of the pulverizing system of 330 MW unit boiler, the oxygen concentration of desiccant in the process of pulverizing and conveying of pulverized coal is controlled within the safe range, the hidden danger of deflagration is eliminated, the safe operation of the pulverizer and pulverizing system is ensured, and the generation of nitrogen and oxygen compounds in the combustion of boiler, the amount of ammonia injection and the mitigation can be achieved by reducing the oxygen concentration of primary air the blockage of preheater and the overload of SCR also increase the flue gas flow of furnace, increase the flue gas temperature of furnace outlet and each section, and increase the flue gas temperature of preheater inlet to move down the crystallization area, which is conducive to soot blowing and unblocking, increase the main reheat temperature under low load, and increase the economy of the unit.