摘要
通过高温热处理将石棉尾矿中的纤维结构分解破坏,获得活性MgO和SiO_(2),实现“解毒”的目的。本试验在石棉尾矿热分析基础上,研究了不同焙烧温度、时间对石棉尾矿焙烧产物MgO、SiO_(2)活性的影响,结合X射线衍射、红外光谱、扫描电镜分析,讨论石棉尾矿在不同焙烧温度和时间下焙烧产物物相组成、化学结构及微观形貌的变化。结果表明,焙烧温度和时间都会对焙烧产物MgO、SiO_(2)活性产生影响,在680℃下焙烧40 min,MgO活性最高,活性MgO质量分数为14.55%;在680℃下焙烧50 min,SiO_(2)活性最高,Si溶出量为3.491 mg/g;焙烧温度在600~700℃范围时,石棉尾矿中蛇纹石脱去内外羟基发生相变,活化产物非晶相含量最高;在700~850℃范围时,焙烧产物开始由非晶态转化为晶态镁橄榄石,MgO、SiO_(2)活性降低。
Through high-temperature heat treatment,fiber structure in asbestos tailings can be decomposed and destroyed,and active MgO and SiO_(2) can be obtained to achieve the purpose of"detoxification".Based on the thermal analysis of asbestos tailings,the effect of different calcination temperature and time on the activity of MgO and SiO_(2) of asbestos tailings calcinated products was studied,and combined with X-ray diffraction,infrared spectrum,scanning electron microscopy analysis,the calcined product phase composition,microstructure and chemical structure changes of the asbestos tailings under different calcination temperature and time were discussed.The results showed that both calcination temperature and calcination time had an effect on the activities of MgO and SiO_(2),among which,the MgO activity reached the highest at 680℃ for 40 min,and the active MgO content was 14.55%.SiO_(2) activity reached the highest when calcined at 680℃ for 50 min,and Si dissolution amount was 3.491 mg/g.At 600-700℃,the inner and outer hydroxyl groups of serpentine in asbestos tailings are removed,and the content of activated amorphous phase is the highest.At 700-850℃,the calcined products begin to transform from amorphous to crystalline magnesium olivine,and the activities of MgO and SiO_(2) decrease.
作者
周鑫
孙红娟
彭同江
罗利明
李瑶
Zhou Xin;Sun Hongjuan;Peng Tongjiang;Luo Liming;Li Yao(Key Laboratory of Solid Waste Treatment and Resource Recycle,Ministry of Education,Mianyang,Sichuan 621010;Institute of Mineral Materials and Application,Southwest University of Science and Technology,Mianyang,Sichuan 621010;Analytical and Testing Center,Southwest University of Science and Technology,Mianyang,Sichuan 621010)
出处
《非金属矿》
CSCD
北大核心
2022年第2期23-27,共5页
Non-Metallic Mines
基金
国家自然科学基金(42072048)。
关键词
石棉尾矿
热活化
反应活性
微观结构
asbestos tailings
thermal activation
reactivity
microstructure
