循环流化床锅炉启动过程建模与仿真
Modeling and Simulation of Startup Process of Circulating Fluidized Bed Boiler
Abstract
通过对循环流化床锅炉床下热烟气点火启动过程进行分析,将启动过程分为两个阶段:投煤前热烟气对惰性床料的纯加热阶段和投煤以后的反应阶段。前一个阶段从全床的热平衡角度考虑建立模型,后一个阶段的模型则由氧浓度,床料,残碳和床温的动态方程所组成。由此建立了一个完整的循环流化床锅炉床下热烟气点火启动过程的简化模型,模型仿真的结果表明了模型的正确性。最后用所建模型模拟了不同操作条件下锅炉的温升曲线。 Via analyzing the startup process of intake hot gas ignition of the circulating fluidized bed boiler, the startup process is divided into two phases: the heating by the gas for inert bed material before adding coal and the reaction after coal is fed.The model for the former is obtained based on the energy balance of the whole bed, while for the latter the model consists of dynamic equations of oxygen concentration, total bed material, unburned carbon mass and total energy.Then a simple startup process model of intake hot gas ignition of circulating fluidized bed boiler was established, the results of simulations indicated the model is right.Finally, the validated model system was used to simulate the curves for temperature increase of CFBB in different operating conditions.