摘要
炼钢过程产生的钢渣和制铝工业排出的赤泥都是排放量巨大且难以利用的固体废物,利用这些固体废弃物制备用于墙体保温的发泡陶瓷材料是一种大宗高值利用途径。本文利用钢渣和赤泥分别添加0.1 wt.%发泡剂SiC制备发泡陶瓷,探究了两种陶瓷配方对发泡过程的影响。研究表明钢渣和赤泥均可以用于制备发泡陶瓷,钢渣发泡陶瓷在1160℃下的主晶相为辉石、钙长石和硅灰石,抗折强度可达到2.60 MPa,密度可达到0.50 g/cm3;赤泥发泡陶瓷在1180℃下的主晶相为透辉石、钙长石和赤铁矿,且生成了钙铁榴石,抗折强度为9.91 MPa,密度为1.00 g/cm3。当发泡陶瓷达到烧成温度时,坯体开始产生液相,此时陶瓷坯体中的Ca2+或Fe2+等组分能够促进SiC的氧化反应并形成大量气体,这些气体在陶瓷液相中形成气孔。与赤泥发泡陶瓷相比,钢渣发泡陶瓷在相同密度下力学性能较低,但是其烧成温度相应较低,液相形成区间大,能够形成更低密度的发泡陶瓷产品。
The steel slag produced by the steelmaking process and the red mud discharged from the alumi-num industry are huge solid wastes and difficult to be reused. Preparation of foamed ceramic ma-terials for wall insulation from these solid wastes is a feasible utilization way with high value-added and large quantity. In this paper, foamed ceramics were prepared by adding 0.1 wt.% SiC as foaming agent into steel slag based ceramic and red mud based ceramics respectively and their effects on the foaming process were studied. The research showed that both steel slag and red mud can be reused to prepare foamed ceramics. The main crystal phases of steel slag foamed ceramics at 1160?C were augite, anorthite and wollastonite. Its flexural strength reached 2.60 MPa with density of 0.50 g/cm3. While the red mud foamed ceramic at 1180?C had main crystal phases of diopside, anorthite, hematite and andradite with flexural strength of 9.91 MPa and density of 1.00 g/cm3. Liquid phase began to appear when the foamed ceramic reached the sintering temperature. At the moment, components such as Ca2+ or Fe2+ in the ceramic body promoted oxidation reaction of the SiC and thereby formed a larger amount of gas and more pores in the liquid phase. Compared with the red mud foamed ceramics at the same density, steel slag foamed ceramics had lower mechanical properties, lower sintering temperature but larger temperature range of liquid phase formation, which was benefit to form lower density foamed ceramic products.
出处
《冶金工程》
2019年第4期223-231,共9页
Metallurgical Engineering
基金
国家自然科学基金资助项目(51474027)
国家重点研发计划资助项目(2016YFB0601304)。