提纯膨润土制备复合黏结剂用于生产球团试验

为降低以磁铁矿粉为原料制备球团时黏结剂膨润土的添加量,探索低品位膨润土在球团工业中的应用,以朝阳某旋流器提纯后膨润土与有机黏结剂CMC进行复配为复合黏结剂,考察添加复合黏结剂对磁铁矿粉制备生球质量的影响。结果表明,在φ150 mm和φ75 mm两级旋流器串联,分级压力分别为0.1 MPa和0.2 MPa的条件下,膨润土原土蒙脱石含量从60.25%富集到81.04%,产率为60.93%、回收率为81.95%。以CMC配入量为提纯后膨润土质量的3%、螺旋挤压次数为3次时制得的复合黏结剂制备球团,可使球团中黏结剂的配比降低到0.8%,在此配比条件下制备的生球落下强度为5.2次,爆裂温度为475℃、生球抗压强度为12.85 N/个,满足球团性能要求。采用复合黏结剂制备球团有利于后续工艺的节能降耗,是未来球团工业发展的趋势之一。

Study on Production of Pellet by Compound Binder Prepared with Purified Bentonite

In order to reduce the addition of bentonite，which is used for preparation of pellets using magnetite powder as main material，explore the application of low-grade bentonite in pellet industry.Influence of adding compound binder on quality of green pellet was investigated，using compound binder mixed with bentonite purified by hydrocyclones and organic binder CMC.The results show that Φ150 mm and Φ75 mm hydroclones in order，with classification pressure of 0.1 MPa and 0.2 MPa respectively，content of montmorillonite is enriched from 60.25% to 81.04% with yield rate of 60.93% and the recovery rate is 81.95%.When compound binder prepared with CMC dosage is 3% of purified bentonite，screw extrusion is 3 times.The matching ratio of binder in pellets can be reduced to 0.8%，the drop strength of green pellets is 5.2 times，explosion temperature is 475 ℃ and the compressive strength of green pellets is 12.85 N/P，which meet the property requirements of pellet.The use of compound binder to prepare pellets is beneficial to the energy saving，and is one of the development trends in pelletizing industry in the future.