关键词: 钒尾矿, 烧结陶粒, 温度制度, XRD, SEM

Abstract: The vanadium extraction tailings form stone coal in Hubei is a high-quality raw material to produce ceramsites.In order to reveal the effect of temperature system on properties and microstructure of roasting ceramsites prepared with vanadium tailing,XRD images and SEM pictures under different roasting temperature and roasting time were used to investigate the effect of the roasting temperature and roasting time on particle strength and water absorption of the ceramsites.The results show: ① the particle strength of the ceramsites increased firstly and then decreased and its water absorption decrease along with the sintering temperature raising and the time prolonging.The reason is that appropriate increase of the sintering temperature or extending sintering time plays a positive role in forming feldspar,and low melting mass was formed by the new feldspar together with silica-alumina mineral such as quartz,which was filled in the blank between particles.Then,relatively even porosities among the ceramsites were produced to increase the particle strength and decrease the water absorption of the ceramsites.But when the roasting temperature and roasting time are much higher,the uniformity flow of the low melting mass within the ceramsites led to holes merging and structure loosing.So,the strength of ceramsites decreased.②Under conditions of the pre-roasting temperature at 400 ℃,the pre-roasting time for 30 min,the roasting temperature at 1 130 ℃and the roasting time for 10 min,the properties of the ceramsites such as water adsorption,cylinder pressure strength,grain coefficient,bulk density and grain size distribution,meet well the requirements of GB/T 17431.1-1998.

Key words: Vanadium tailing, Roasting ceramsites, Temperature system, XRD, SEM