烧结矿竖冷炉内物料的偏析

Segregation of sinter particles in sinter shaft cooler

烧结机竖式冷却回收烧结矿显热工艺是一种新型余热回收技术,其本质上是气固逆流换热散料床,梅钢从环保和节能两方面考虑引入该技术代替传统的环冷机对其烧结矿余热进行回收利用。以烧结矿竖冷炉为研究对象,利用离散单元法(DEM)模拟缓冲仓内和竖冷炉内烧结矿颗粒的偏析行为,分别研究在工业上可行的缓解一次偏析和二次偏析的方法。计算结果显示,在缓冲仓加入分料板会使烧结矿颗粒在中心位置形成料坑,且坑内颗粒粒度明显增大,表明此方法可缓解一次偏析;在进料喉管底部增加分流管可以有效调节烧结矿颗粒的运动方向,控制颗粒落在更有益的位置,从而达到缓解二次偏析的目的,另外,通过调整分流管的倾斜角度还可以进一步优化烧结矿颗粒的二次偏析。

The process of recycling the sensible heat of sinter by using a sinter shaft cooler is a new technology.The shaft cooler is a typical powder bed with gas-solid countercurrent heat transfer.Considering environmental protection and energy conservation,the process of sinter shaft cooler was introduced into Meishan Steel to replace the traditional ring cooler.Focusing on the segregation of particles in the surge bunker and the furnace,the DEM(Discrete Element Method)is used to study how to decrease the first segregation and the secondary segregation on an industrial scale.The result of the simulation indicates two conclusions.Firstly,the particle pit is formed in the center region of surge bunker after adding aplate for separating the particles and the particle size in the pit is bigger than other regions.This phenomenon can decrease the first segregation.Secondly,the landing position in the furnace can be controlled in a beneficial direction after adding a shunt on the bottom of the feeding pipe and the purpose of decreasing the secondary segregation can be achieved.In addition,the behavior of secondary segregation can be further optimized by adjusting the tilt angle of the shunt.