鄂尔多斯盆地北缘煤炭固体废弃物中铝的特征

Aluminum Characteristics of Solid Wastes from Coal Fields in North Side of Ordose Basin

为了研究煤炭固体废弃物中铝的含量及赋存状态,探讨其中氧化铝提取的可能性,在处理煤炭固体废弃物的同时扩大我国自然铝资源,分别采用化学分析、XRD、SEM及粒度分布等方法对鄂尔多斯北缘准格尔等煤田煤矸石及粉煤灰进行了化学成分、物相组成及结构测定。结果表明:该地区的煤矸石和粉煤灰中氧化铝的质量分数均接近或大于40%,达到了铝矿床的工业品位;煤矸石中铝主要赋存在高岭石和勃姆石中,OF灰中铝主要赋存在莫来石中,而CFB灰中铝则赋存在非晶态物质中;同时CFB灰与OF灰相比具颗粒细小且粒度分布均匀、颗粒形态呈絮状、结构活性高等特点;CFB灰中的铝活性高易提取,煤矸石中的铝只需要热活化即可提取,而OF灰中的铝则需要化学活化才可以提取。高铝煤炭固体废弃物中铝的有效提取可以补充铝资源的不足。

To research the content and existence states of aluminum in gangues and fly ash,and to discuses the extraction possibility of aluminum oxide,and to increase the aluminum resource corresponding to make the use of solid wastes from coal fields,the compositions,constitutions and structures of gangues and fly ash from north side of Ordose basin were tested by chemical analysis,XRD,SEM and granularity distribution.The result is that the contents of aluminum oxide both in gangues and in fly ash are approximately or more than 40%,it is more than the industry grade of aluminum deposit.The aluminum of gangues is mainly in kaolinite and boehmitthe,the aluminum of OF ash is mainly in mollite,and the aluminum in CFB ash is mainly in the amorphous matters.At the same time CFB ash compare to OF ash has the character of smaller grain size and equality granularity,wadding grain form and high structure activity.The conclusion is that the aluminum in CFB ash has high activation and can be extracted easily,the aluminum in gangues can be extracted when the gangues are baked,and the aluminum in OF ash can be extracted when it is activated by chemically methods.The problem of aluminum recourse shorting can be solved by the aluminum extracting of high aluminum solid wastes.