负荷分配对流化床-煤粉复合燃烧锅炉热力特性的影响

Effect of Load Distribution on Thermal Dynamics of CFB Combining with Pulverized Coal Firing

针对树皮流化床－煤粉复合燃烧锅炉的特点，提出了流化床按基本蒸汽负荷设计的思路。以７５ｔ／ｈ树皮流化床－煤粉复合燃烧锅炉为例，预测了总蒸汽负荷一定条件下，燃树皮产汽负荷与燃煤产汽负荷变化时锅炉的热力特性。计算表明，随着燃树皮产汽负荷的增加，煤粉炉膛的绝热燃烧温度和流化床温度降低；而炉膛出口烟温、排烟温度、空气预热器出口风温和高温风风量、减温水量等热力参数升高，但变化幅度不大，证明了前述设计思路的可行性。在一定的基本蒸汽负荷下，燃树皮产汽负荷的上限值可根据流化床中树皮的稳定燃烧温度和减温系统的工作能力来确定。

The design method was put up according to the base steam load when the character of the combined combustion boiler was taken into account of bark CFB and pulverized coal firing. The boiler thermal dynamic character was predicted by the example of a 75 t/h combined combustion boiler when the total steam load was given and the steam load produced by the bark and the pulverized coal changed. Calculation showed that the isothermal combustion temperature of pulverized coal furnace and the fluidized bed temperature decreased when the steam load produced by the bark increased. Some other parameters contrarily decreased but changed little. These parameters are flue gas temperature of furnace exit, released flue gas temperature,air temperature of the air heater exit, and flux of high temperature air, and flux of water in the attemperator. It confirmed the design method feasible. The maximum steam load produced by the bark was determined by the bark fixed combustion temperature and the capacity of attemperator system when the basic steam load was given.