铁尾矿加气混凝土制备工艺及结构形成机理分析  

Reaction mechanism on autoclaved aerated concrete made from low-grade vanadium titanium iron tailings

作　　者：罗立群[1] 舒伟[1,2] 程琪林 谭旭升 

机构地区：[1]武汉理工大学资源与环境工程学院,湖北武汉430070 [2]绍兴市质量技术监督检测院,浙江绍兴312000

出　　处：《化工进展》2017年第4期1482-1490,共9页Chemical Industry and Engineering Progress

基　　金：国家"十二五"科技支撑计划项目(2013BAB03B03)

摘　　要：以低贫钒钛铁尾矿为主要原料制备蒸压加气混凝土,其制品抗压强度超过3.5MPa,干体积密度为620kg/m^3,达到了A3.5B06级合格品要求。利用X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、热重-差示扫描量热仪(TG-DSC)、扫描电子显微镜(SEM)等手段,重点研究了蒸压加气混凝土砌块的抗压强度和干体积密度、官能团的振动、相变过程和微观结构等特性。结果表明:在常温常压下,硬化坯体中出现了少量结晶差的C-S-H凝胶和钙矾石晶体,铁尾矿中各成分参与化学反应只有很少量的活性组分。在蒸压养护条件下,混合物料中的钙质材料水化形成的Ca(OH)_2与铁尾矿、石英砂中的游离SiO_2和Al_2O_3反应得到了托贝莫来石,钙矾石消失;水化产物的晶簇集合体和骨料交织在一起,形成良好的网状致密结构,对提高制品的强度有积极作用。Based on low-lean vanadium and titanium iron tailings as raw material, the technology of autoclaved aerated concrete （AAC） block was developed, in which compressive strength was more than 3.5MPa and dry bulk density prepared was about 620kg/m3. The products was slightly more than A3.5B06 grade qualification requirements. The physical and mechanical properties, the vibration of the functional group, phase transformation process, microstrucmre, etc. of aerated concrete block were tested by X-ray diffraction （XRD）, fourier transform infrared spectroscopy （FTIR）, thermogravimetric and differential scanning calorimeter （TG-DSC）, scanning electron microscope （SEM） and other modem analysis test methods. Under the atmospheric pressure, the iron tailings was a kind of inertia industrial waste residue. Only a small amount of active component in iron tailings participated in the chemical reaction. Small amounts of the hydrated calcium silicategel and ettringite were in the hardened body. Under the autoclaved curing condition, the activity of iron tailings was good. Free SiO2 and Al2O3 and mixture of Ca（OH）2 took place chemical reaction to generate tobermorite. A dense mesh structure was formed by hydration products of crystal cluster fitting aggregating together, which had positive effect to improve the strength of the products.

关 键 词：低贫钒钛铁尾矿 加气混凝土 水化产物 托贝莫来石 反应机理 

分 类 号：TU528.2[建筑科学—建筑技术科学] TD926[矿业工程—选矿]