基于gCCS的330MW循环流化床锅炉燃烧系统动态建模

Dynamic Modeling for the Combustion System of a 330MW CFB Boiler Based on gCCS

针对某330 MW循环流化床锅炉燃烧系统,利用机理分析法建立锅炉氧浓度、床料质量、残碳质量以及床温的动态数学模型。首先将循环流化床锅炉燃烧过程简化,建立燃烧系统动态数学模型,用gCCS(gPROMSCarbom Capture and Storage)软件求解仿真;并根据现场试验数据对模型进行动态验证。在此基础上,利用所建模型进行阶跃扰动仿真计算。仿真结果表明,给煤的增加会使密稀相区氧浓度下降,床温升高;一次风的增加使密稀相区氧浓度升高,密相区床温下降,而稀相区床温呈现先上升后下降的规律;二次风的增加使密稀相区床温下降,密相区氧浓度先上升后下降,而稀相区氧浓度增大。所得研究结论可为循环流化床锅炉运行、燃烧控制系统的设计和优化提供理论基础。

In view of the combustion system of circulating fluidized bed boiler, the mathematical model of the oxygen concentration, the bed material quality, the residual carbon mass and the bed temperature of boiler is established by the mechanism analysis method. Firstly, the combustion process of circulating fluidized bed boiler is simplified, the dynamic mathematical model of combustion system is established, and the simulation is solved by gCCS software. And the dynamic simulation is carried out to verify the correctness of model according to the field test data. On the basis of this, doing step disturbance simulation on the model. Simulation results show that, the increase of coal supply will decrease the oxygen concentra- tion in the dense and dilute phase, and increase the bed temperature. The increase of primary air increases the oxygen concentration in the dense and dilute phase, decreases the bed temperature of the dense phase region, while the bed temperature of the dilute phase increases first and then decreases. The increase of secondary air increases the bed temperature in the dense and dilute phase, and the oxygen concentration in the dense phase increases first and then decreases, while the oxygen concentration in the dilute phase increases. The conclusions of the study can provide theoretical basis for the operation of circulating fluidized bed boiler, design and optimization of combustion control system.