热烧结矿竖式冷却过程传热特性

Heat transfer characteristics in process of hot sinter vertical cooling

与传统环冷相比,烧结竖冷拥有漏风率低、换热效率高的优势。为此利用竖冷试验装置,在某烧结厂取热风与热烧结矿研究了竖式冷却过程气固对流换热特性。研究表明,烧结矿竖式冷却过程中影响传热特性的主要因素为冷却风的流量及温度。烧结矿和冷却风对流换热系数随着烧结矿温度的升高而增大,且随着冷却风流量的增大以及冷却风温度的降低,对流换热系数也随之增大。基于白金汉定理,结合试验数据拟合得出了描述烧结矿与冷却风传热特性的准数关联式,其模拟性较好且平均相对误差为7.25%。

Compared with traditional circulating cooling process,sinter vertical cooling process has the advantages of low air leakage rate and high heat transfer efficiency.A study on the gas-solid convection heat transfer characteristics in the process of sinter vertical cooling was carried out in a sintering plant which can offer the hot air and hot sinter using a vertical cooling device.The study shows that the main factors influencing the heat transfer characteristics in the sinter vertical cooling process are the flow rate and the temperature of cooling air.The convection heat transfer coefficient between sinter and cooling air increases with the increasing of the sinter temperature,and also increases with the increasing of the cooling air flow rate and the decreasing of the cooling air temperature.Based on Buckingham theorem,an experimental correlation for describing the heat transfer characteristics between sinter and cooling air is obtained by fitting the experimental data,which can give a good prediction and its average relative error is7.25%.