摘要
为了扩大铁尾矿作为二次资源的利用范围,以铁尾矿、石英、钾长石为原料,利用SiC发泡法制备了闭孔轻质陶粒.借助XRD、SEM以及FactSage软件等手段研究了烧成温度(1 120、1 130、1 140 ℃保温3 h)、陶粒粒径(≤2.5、5~2.5、10~5 mm)以及发泡剂SiC的加入量(质量分数分别为1.0%、1.5%、2.0%、2.5%、3.0%)对陶粒结构和性能的影响.结果表明:1)随着烧成温度和SiC发泡剂加入量的增加,陶粒的堆积密度和承载能力均呈下降趋势,陶粒内部具有细孔状、蜂窝状、中空状3种气孔结构;2)当烧成温度为1 130 ℃,铁尾矿、钾长石、石英和SiC加入量(w)分别为80.5%、10%、7%和2.5%,陶粒的粒径范围为10~5 mm时,可获得堆积密度为0.69 g·cm-3、承载能力为311.2 N的轻质陶粒.
Abstract
To expand the utilization of iron tailings as secondary resources,lightweight closed-cell ceram-sites were prepared using the SiC foaming method with iron tailings,quartz,and potassium feldspar as raw materials.The effects of the firing temperature(1 120,1 130 and 1 140 ℃ for 3 h),the ceramsite particle size(≤2.5,5-2.5 and 10-5 mm),and the addition of foaming agent SiC(1.0%,1.5%,2.0%,2.5%and 3.0%,by mass)on the structure and properties of the ceramsites were studied by XRD,SEM,FactSage software,etc.The results show that:(1)as the firing temperature and SiC addition increase,the bulk densi-ty and bearing capacity of the ceramsites decrease,and the ceramsites exhibit three pore structures:fine pore,honeycomb,and hollow;(2)with the firing temperature of 1 130 ℃,additions of 80.5 mass%iron tail-ings,10 mass%potassium feldspar,7 mass%quartz and 2.5 mass%SiC,as well as the ceramsite particle size of 10-5 mm,lightweight ceramsites can be obtained with a bulk density of 0.69 g·cm-3 and bearing capacity of 311.2 N.