宜昌某高岭土剥片试验

宜昌某高岭土矿高岭土含量虽达95%左右,但-2μm粒级产率仅占30%,且有10%的叠片状未剥离高岭土,层间的着色有机杂质直接煅烧难以高效脱色。为获得高品质高岭土熟料,对试样进行了剥片工艺条件研究,并对剥片前后的高岭土进行了SEM分析和熟料白度研究。结果表明,在磨矿前一次性加入与试样质量比为3%的分散剂六偏磷酸钠,搅拌磨中刚玉质中球(=1.2 mm)与小球(=0.8 mm)的体积比为0.8∶1.5,介质充填率为70%,磨矿浓度为70%,剥片转速为800 r/min,磨矿时间为180 min情况下,剥片产品-2μm粒级产率为96.62%,普遍为表面平滑、颗粒均匀的高岭土单片;剥片前后高岭土熟料的白度分别为76.84%和82.08%,剥片使熟料的白度提高了5.24个百分点。剥片后高岭土的粒度和熟料的白度均达到高档填料的质量要求。

Experiment of the Stripping of Kaolin in Yichang

The kaolin content of a kaolin ore in Yichang is about 95%，but its fraction yield in -2 μm size just reaches 30% and 10% of kaolin has not been striped which contains organic coloring impurities，so it is hard to realize decolorization by direct roasting.In order to obtain high quality kaolin clinker，the conditions of splitting process are studied，and the SEM photos and whiteness of clinker of kaolin clay before and after the splitting are analyzed.It is obtained that stripping product in -2 μm size reached the yield of 96.62% under conditions of volume ratio of medium corundum mill ball (Φ=1.2 mm) and little ball (Φ=0.8 mm ) 0.8∶1.5，grinding concentration 70%，grinding medium fill rates 70%，stripping speed 800 r/min for 180 minutes and dispersant sodium hexametaphosphate accounting for 3% of the raw materials by adding once before grinding.The products are even grained monolithic kaolin with smooth surface;the whiteness of kaolin clinker is increased from 76.84% to 82.08% after splitting，about by 5.24%.The granularity of kaolin and the whiteness of kaolin clinker after splitting can reach requirements for high quality fillers.