基于脉冲燃烧控制的退火炉热负荷分配模型  

Distribution model of heating output based on on-off controlled annealing furnace

作　　者：任伟超 朱国明[1] 李洋龙 李冠雄 周欢 王道金 REN Wei-chao;ZHU Guo-ming;LI Yang-long;LI Guan-xiong;ZHOU Huan;WANG Dao-jin(School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China;Cold Colling Department,Shougang Jingtang United Iron and Steel Co.,Ltd.,Tangshan 063200,Hebei,China;Department of Metallurgical Process,Research Institute of Technology of Shougang Group Co.,Ltd.,Beijing 100041,China)

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]首钢京唐钢铁联合有限责任公司冷轧部,河北唐山063200 [3]首钢集团有限公司技术研究院冶金过程研究所,北京100041

出　　处：《钢铁》2022年第1期151-158,共8页Iron and Steel

摘　　要：脉冲燃烧控制技术以其良好的动态响应性、较高的炉温控制精度、较低的燃气消耗及污染物排放水平等优点,广泛应用于各类加热炉。对于立式退火炉而言,常见的加热模型有3种,即比例模型、窄带钢模型、正常模型。生产中操作人员可以根据带钢在加热段跑偏、瓢曲风险选择相应的模型,但上述这3种模型均无法避免因烧嘴频繁开启和关闭导致的辐射管骤冷骤热,进一步引起辐射管变形、开裂,点火电极、控制阀消耗异常以及煤气压力波动大等问题。为了降低烧嘴开启、关闭频次,达到降低烧嘴故障率、减缓辐射管开裂趋势等目的,提出了一种针对脉冲控制的退火炉专用"爬楼梯"式热负荷输出分配模型。通过拟合加热段板温控制器输出值与加热段各列热负荷输出值之间的关系,采用插值法得到加热段热负荷输出分配模型的修正函数,满足了模型计算值与板温控制器输出值相等的要求。通过调整加热段每一列热负荷输出上、下限,使加热段每列热负荷输出呈现"爬楼梯"式分布,实现了立式退火炉低功率加热段入口区域烧嘴不燃烧和出口区域烧嘴一直燃烧的功能。经过测试,在一个完整的燃烧周期内,爬楼梯式分配模型可大幅度降低烧嘴开启和关闭频次。当加热段板温控制器输出为89.6%时,传统模型控制下烧嘴开关频次达到324次,而"爬楼梯"式分配模型仅为32次。The on-off controlled combustion technology is widely used in various heating furnaces because of its good dynamic response, high temperature control accuracy, low gas consumption and pollutant discharge level. For vertical annealing furnace, there are three common heating models: the proportional model, the narrow model, the normal model. In line running status, operators can choose corresponding models according to the risks of strip deviation and buckling in the radiant tube heating section, but none of these three models are unable to avoid the problems of sudden cooling and heating of the radiator tube due to frequent opening and closing of burners. It could further induce the deformation and cracking of radiation tubes, abnormal consumption of ignition electrodes and control valves and large fluctuation of gas pressure. In order to reduce the frequency of burner opening and closing times, a "stair-climbing" type heating output distribution model was established. The relationship between the controller output of strip temperature and the heating output of each column at radiant tube heating section was fitted, and the correction function of heating output distribution model for the radiant tube heating section was obtained via the interpolation. It met the requirement that the calculated values of the model was consistent with the actual values. The upper and lower limits of each column of heating output were adjusted so that the heating output was distributed in a "stair climbing" manner. The function that the burners in the inlet area of the low power heating section do not work and the burners in the outlet area always work was realized in vertical annealing furnace. A completed combustion cycle was tested. It showed that the "stair climbing" model can greatly reduce the frequency of burner opening and closing times, under a complete combustion cycle. At the condition of 89.6% strip temperature controller output at the radiant tube heating section, the burner was switched on and off for 324 times, whereas

关 键 词：立式退火炉 加热段 烧嘴 脉冲控制 热负荷输出 “爬楼梯”式分配模型 

分 类 号：TG155.1[金属学及工艺—热处理]