链箅机—回转窑热工系统的控制模型研究

Research on control model of grate-rotary kiln thermal system

铁矿球团链箅机—回转窑工艺热工系统具有控制对象复杂、调节过程长且滞后以及各热工参数之间相互耦合的特点,导致该工艺在调节和控制时无法有效推测出各热工参数的变化趋势,造成调节无法达到预期。针对这些问题,本文基于某钢铁企业球团工序的生产数据,采用数据挖掘及相关性分析的方法,深入研究链箅机—回转窑热风循环系统之间的关联性,并构建相关数学模型。结果表明:回转窑窑头烧嘴参数(喷气量、助燃流量)与窑头、窑尾温度以及链箅机—回转窑热风循环系统中各热工参数之间的显著性均为0.000,同时相关系数基本上都在0.900以上,而且各参数之间所构建的回归模型误差较小,经现场生产验证,其中回转窑窑尾、窑头温度与回转窑高炉煤气用量X_(1)、焦炉煤气用量X_(2)、助燃流量X_(3)构建的回归方程K_(5)=858.534+0.027X_(1)+0.030X_(2)+0.027X_(3)和K_(6)=337.735+0.047X_(1)+0.068X_(2)+0.124X_(3)的误差仅为4.9%和2.4%,可作为现场热工参数的预测模型。

The thermal system of iron ore pellet grate-rotary kiln process characterizes complex control object,long and lagging adjustment process and mutual coupling of various thermal parameters,as a result,the process cannot effectively predict the changing trend of each thermal parameter during regulation and control process,while the adjustment does not meet expectations.In order to solve these problems,based on the production data of pelletizing process in an iron and steel enterprise,the methods of data mining and correlation analysis are used to deeply study the correlation between grate-rotary kiln hot air circulation system,and the relevant mathematical model is constructed.The results show that the significance between the burner parameters of the rotary kiln head(jet volume,combustion-supporting flow)and the temperature of the kiln head and kiln tail and the thermal parameters of the grate-rotary kiln hot air circulation system are all 0.000,the correlation coefficient is basically above 0.900,and the regression model constructed between the parameters has a small error,which has been verified by on-site production,among which the error of the regression equation K_(5)=858.534+0.027X_(1)+0.030X_(2)+0.027X_(3) and K_(6)=337.735+0.047X_(1)+0.068X_(2)+0.124X_(3) set up among the the temperature of the kiln head and kiln tail and blast furnace gas consumption X_(1),Coke oven gas consumption X_(2) and combustion-supporting flow X_(3)are only 4.9%and 2.4%,which can be used as a prediction model for field thermal parameters.