摘要
为揭示煤矸石热活化制度及颗粒细度对其火山灰活性的影响机制,采用X射线衍射、傅里叶变换红外光谱、差热分析、扫描电镜及活性指数多尺度表征手段,系统研究了煅烧温度(500、600、700、800、900℃)、煅烧时间(30、60、90、120、150 min)及研磨时间(20、30、40 min)对煤矸石矿物相变、微观结构演化及活性指数的影响。结果表明,煤矸石在600℃开始脱羟基反应,高岭石结构解离;800℃煅烧120 min时羟基完全脱离,形成非晶态偏高岭石,硅氧四面体与铝氧八面体解聚程度最大,火山灰活性指数达峰值(89.19%);研磨时间的延长改变了煤矸石的细度,研磨30 min时细化效果最佳,D50<10μm,煅烧后的活性最高,但过度研磨(40 min)引发颗粒发生二次团聚、粒径增大、活性位点减少,导致火山灰活性降低。研究结果可为煤矸石的活性激发提供理论依据与技术参考。
In order to reveal the influence mechanism of thermal activation system and particle fineness of coal gangue on its volcanic ash activity,a systematic study was conducted using X-ray diffraction,Fourier transform infrared spectroscopy,differential thermal anal-ysis,scanning electron microscopy,and multi-scale characterization of the activity index.The effects of calcination temperature(500,600,700,800,900℃),calcination time(30,60,90,120,150 min),and grinding time(20,30,40 min)on the mineral phase transi-tion,microstructural evolution,and activity index of coal gangue were investigated.The results indicated that the dihydroxylation of coal gangue began at 600℃,leading to the dissociation of the kaolinite structure;when calcined at 800℃for 120 minutes,hydroxyl groups were completely removed,forming amorphous metakaolinite with the highest degree of depolymerization of silicon-oxygen tetrahedra and aluminum-oxygen octahedron,resulting in a peak volcanic ash activity index of 89.19%;adjusting the fineness of coal gangue was changed by extending grinding time revealed that the optimal refinement effect(D50<10μm)was achieved after 30 min for grinding,yielding the highest post-calcination activity.However,excessive grinding(40 min)induced secondary particle agglomeration,increased particle size,reduced active sites,and consequently decreased volcanic ash activity.The research findings can provide a theoretical basis and technical reference for the activation of coal gangue.
作者
申宏栋
Shen Hongdong(Jiaozuo Qianye New Materials Co.,Ltd.,Jiaozuo 454100,China)
出处
《能源与环保》
2025年第8期160-166,共7页
CHINA ENERGY AND ENVIRONMENTAL PROTECTION
关键词
煤矸石
热活化
偏高岭石
火山灰活性
细度
coal gangue
thermal activation
metakaolinite
volcanic ash activity
fineness
作者简介
申宏栋(1980-),男,河南长垣人,高级工程师,现从事绿色矿山、建材工作。
