摘要
以铁尾矿和煤矸石为主要原料,掺加部分污泥及其他辅料制备铁尾矿-煤矸石-污泥复合烧结砖,分析了铁尾矿、煤矸石、污泥与其他辅料的矿物组成、化学成分及粒度特征,考察了铁尾矿、煤矸石和污泥配比、坯体成型压力、烧结温度对烧结砖质量的影响,借助XRD、SEM、ICP等手段分析了烧结砖中重金属离子的固化效果与微观结构。结果表明:铁尾矿-煤矸石-污泥复合烧结砖的制备条件以铁尾矿∶煤矸石∶污泥∶页岩配比为54∶30∶6∶10,成型压力20 MPa为宜;烧结温度1 100℃,保温时间3.0h。制品经过高温烧结后,物料中重金属被固化或部分挥发,重金属离子浸出率大小为:Pb^(2+)>Cu^(2+)>Zn^(2+)>Cr^(3+),且符合GB5085.3—2007的规定。显微分析表明:未烧砖坯断面多为离散颗粒、大小和排列均无序;高温烧结后新生成的玻璃晶相明显增加而呈现液相固结,显微表面更加平整均匀致密。
Composite sintered bricks,which main materials was consisted of iron tailings,coal gangue and sewage sludge,were preparation by using iron ore tailings and coal gangue as main raw materials and adding some sludge and other auxiliary materials in the paper.The minerals composition,chemical composition and particle sizes of iron ore tailings,gangue,sewage sludge and other auxiliary materials were analyzed.The effects of iron ore tailings,coal gangue and sewage sludge ratio,bricks＇body forming pressure and sintering temperature on the quality of sintered bricks were investigated,respectively.The curing effects and microstructure of heavy metal ions in sintered bricks were analyzed by means of XRD,SEM and ICP.The results show that the preparation conditions of iron ore tailings-coal gangue-sewage sludge composite sintered bricks are iron ore tailings：coal gangue：sludge：shale ratio is 54∶30∶6∶10,which forming pressure 20 MPa as well as sintering temperature 1 100 ℃,holding time 3.0 his appropriate.After the high temperature sintering,the heavy metal in the materials is almost cured or partially volatilized.Meanwhile,the leaching rate of heavy metal ions is Pb^2＋〉Cu^2＋〉Zn^2＋〉Cr^3＋ and conforms to GB5085.3—2007.Microscopic analysis shows that sections of the non sintered bricks are almost discrete particles,the size and arrangement of small particles are disordered.After the high temperature sintering,the newly formed glass with crystal phase is obviously increased and the liquid phase is consolidated,and the micro surface is more uniform and compact.
出处
《中国矿业》
北大核心
2018年第3期127-131,137,共6页
China Mining Magazine
基金
国家重点研发项目资助(编号:2017YFC0703202)
承德市科技项目资助(编号:201606A080)
关键词
铁尾矿
煤矸石
污泥
烧结砖
制备
iron ore tailing
coal gangue
sewage sludge
sintered brick
preparation
