纤维化膨润土制备及其在铁精矿球团中的应用

Preparation of fibrosis bentonite and its application in iron ore concentrate pellet

在搅拌磨机械力的作用下添加有机分散剂制备纤维化膨润土,将制得的纤维化膨润土喷洒在铁精矿成球长大区进行造球,研究纤维化膨润土的性能及其对铁精矿球团质量的影响。研究结果表明:纤维化的膨润土在加热脱水的过程中,脱水速率明显降低,持水能力明显提高,经纤维化后膨润土粒度变小、比表面积变大,分散度提高,原来的多层片状结构,基本解离成单层结构。与常规造球相比,在生球长大区喷洒纤维化膨润土进行强化造球,生球的抗压强度、落下强度和爆裂温度分别从11.0 N/个,1.9次/0.5 m和490℃提高到14.1 N/个,3.4次/0.5m和540℃,900℃预热15 min和1 280℃焙烧10 min所获得的预热球和焙烧球的抗压强度分别从301 N/个,2 653N/个提高到408 N/个和2 700 N/个。

Fibrosis bentonite was firstly prepared by mixing with organic dispersant in stirred mill, then pelletizing experiments were carded out with it in iron ore concentrate pellets growing area. The properties of fibrosis bentonite and its performance in iron ore pelletizing were studied. The results show that the dehydration rate of fibrosis bentonite reduces Significantly during the heating process, and its moisture holding capacity is improved obviously. The bentonite particle size becomes smaller, specific surface area becomes larger and the degree of dispersion is improved. Moreover, the original multilayer chip structure of bentonite turns into single layer. Strengthening the pelletizing by spraying fibrosis bentonite in ball growing area, the compression strength, drop strength and explosion temperature of green ball will reach 14.1 N/ball, 3.4 times/0.5 m and 540 ℃ from 11 N/ball, 2.1 times/0.5 m and 490℃ respectively compared with the conventional pelletizing. Moreover, compression strength of the preheated ball rises to 408 N/ball from 301 N/ball with 15 min preheating at 900℃ and compression strength of the roasted ball is also improved to 2 700 N/ball from 2 653 N/ball after being roasted for 10 min at 1 280℃.