燃煤链条炉排工业锅炉燃烧数值模型研究

Numerical Modeling Research for Coal Combustion in Traveling Grate Industrial Boilers

针对燃煤链条炉排工业锅炉的燃烧过程中床层内部存在复杂的传热、传质及物理化学反应过程等特点开发了三维床层和炉膛耦合的燃烧数值计算模型,模型包含了煤燃烧过程中水分蒸发、挥发析出、气相反应、焦炭燃烧和传热传质等基本的化学物理过程,同时考虑了大粒径煤颗粒内部的非等温传热特性,并通过实验测试与数值模拟对数值模型进行校核,实验结果与模型计算吻合得较好,从而验证了计算模型的准确性。燃煤链条炉排工业锅炉燃烧数值模型的建立为实现燃煤工业锅炉的优化设计和运行指导提供了先进的设计手段和理论支持。

A 3D mathematical model for coal combustion in traveling grate boilers has been developed.The model contains basic chemical and physical processes during coal combustion including water evaporation,devolatilization,homogeneous reaction,char combustion and heat and mass transfer.A non-isothermal particle model is also proposed,in order to accommodate temperature gradients within combusting particles.To verify the model,concentrations of gas species at the bed surface have been measured in a real chain grate stoker.Predicted results are in reasonable agreement with experimental data.The model has provided a basis for studying the effect of major parameters influencing boiler behavior,for optimizing combustion conditions and design.