利用高碳铬铁合金渣制备轻骨料的实验研究

Sintering Research on Lightweight Aggregate Produced from High Carbon Ferrochrome Slag

以高碳铬铁合金渣和粘土为主要原料,添加少量添加剂焙烧轻骨料,并对成品轻骨料基本性能和微观结构进行了测试和分析。结果表明:随渣掺量增加,骨料烧胀温度提高,烧结范围变窄;焙烧温度的升高使堆积密度呈下降趋势,而孔径及孔隙率呈增加趋势。碳铬渣含量为70%时,可制备出满足GB/T 17431.1—2010中密度等级为500级要求的优质轻骨料,其堆积密度及表观密度分别为420kg/m3和884kg/m3,颗粒强度达4.26MPa,吸水率为1.19%,孔隙率为40%,内部呈蜂窝状闭孔。XRD结果表明粘土中铁离子置换镁橄榄石及镁铝尖晶石中镁离子形成镁铁橄榄石和铁铝尖晶石固溶体,有效降低骨料的焙烧温度。

High carbon ferroehrome slag and clay are mixed with additive to produce lightweight aggragate, the prop erty and microstrueture are analyzed. The results show that= as the content of slag increases, expanding temperature be- comes high, sinering range becomes narrow. And the rise of sintering temperature leads to a reduction of bulk densiy, while a rise of pore sizes and porosity. The 70% slag content aggregates have a perfect properties： bulk densty is 420 kg/cma , apparent density is 884 kg/cma , particle strength is 4. 26 MPa, water absorption is 1. 19% and porosity is 40%, which meets the 500 grade high quality lightweight aggragates in standard of GB/T 17431.1--2010. XRD dates in- dicate that Fe2＋ in the clay has replaced Mge＋ in the forsterite and spinel to form solid solution such as hortonolite and hereynite, this phenomenon has effieetivity lowered sintering temperature.