响应曲面法优化内配兰炭赤铁矿球团焙烧工艺

Roasting technology of semicoke-burdened hematite pellets optimized by response surface methodology

为了有效解决赤铁矿球团焙烧能耗高的难题,对赤铁矿球团进行内配兰炭处理并利用响应曲面法对球团焙烧工艺进行了优化试验研究。通过单因素试验确定主要影响因素和水平,对内配兰炭赤铁矿球团各影响因素进行Box-Behnken设计,建立了用于球团抗压强度预测的多元回归模型,并对焙烧温度、焙烧时间、空气流量、兰炭配比以及它们之间的交互作用进行了研究和优化。得到最佳焙烧工艺,焙烧温度为1 292℃,焙烧时间为18.5 min,空气流量为3.2 L/min,兰炭配比为1.5%。最佳条件下的内配兰炭赤铁矿球团抗压强度为2 578.3 N,与响应目标值2 500 N相近,相对误差仅为3.13%,表明响应曲面法预测模型具有准确性和可靠性。

The main purpose of this paper is to discover the optimal roasting technology of hematite pellets burdened with semicoke by response surface methodology （RSM） to effectively solve the problem of high energy consumption of the hematite pellet roasting. The main influence factors and levels were confirmed by single factor test, the Box-Behnk- en design was used in systemically researching the effects of main process parameters on the compressive strength of semieoke-burdened hematite pellets. The multiple regression equation for predicting compressive strength was estab- lished. The parameters such as roasting temperature, roasting time, airflow volume, semicoke additive amount and their interaction were researched and optimized as well. The optimal values of the roasting process parameters were found at roasting temperature 1 292 ~C , roasting time 18.5 min, airflow volume 3.2 L/min and semicoke additive amount 1.5%. Under the condition of optimized process conditions, the compressive strength of semicoke-burdened he- matite pellets was 2 578.3 N, very close to the response target value of 2 500 N. Experimental verification shows that the relative error between experimental and predicted values is simply 3.13%. The results show that the mathematical model is quite accurate and creditable.