针对循环流化床锅炉热量信号的滞后性,提出一种利用燃烧过程的易测信号来计算锅炉残碳量和热量的方法.首先将循环流化床锅炉燃烧系统分为密相区、稀相区和绝热旋风分离器区,基于物料质量平衡和热量平衡模型,计算出绝热旋风分离器区的燃烧份额.然后通过机理分析建立残碳量模型,根据残碳量和风量构造热量模型,基于某300MW循环流化床锅炉的试验数据,利用扩展Kalman滤波技术对285MW和200MW负荷下炉内的残碳量和热量进行估算,并与文献的计算结果进行对比分析.结果表明:该方法计算结果与文献中计算结果基本吻合,验证了该模型的正确性.
To overcome the deficiency of delayed heat release signals from circulating {luidized bed (CFB) boiler, a method was put forward for calculation of the heat release and carbon residue by using easily measured signals of the combustion process. The specific way is to firstly divide the combusion system into dense phase area, dilute phase area and adiabatic cyclone separator area, then calculate the combustion share in adiabatic cyclone separator area based on materials mass and heat balance model, and finally build up carbon residue model by mechanism analysis and heat release model according to carbon residue and air volume. Based on experimental data of a 300 MW CFB boiler, and using extended Kalman filter technolo- gy, the in-furnace carbon residue and heat release were calculated respectively at loads of 285 MW and 200MW, of which the results were compared with relevant literature data. Results show that the calculated results basically agree with relevant literature data, proving the model to be accurate and reasonable.