Analysis of the characteristics and utilization of coal gangue in the NO.1 coal mine of Pingdingshan mine area

Coal gangue samples were collected from the gob piles in NO.1 coal mine of Pingdingshan mine area.After being crushed,ground,homogenized and quartered,the chemical composition and mineral composition of the coal gangue were investigated by the conventional chemical analysis,XRF,XRD,SEM,EDS,FTIR and DSC-TG.The radioactivity of coal gangue was detected by high-purity germanium γ-ray.The proximate analysis and the calorific value of coal gangue were carried out according GB/T212-2008 and GB/T213-2008.The results show that the main chemical compositions of coal gangue are SiO₂ and Al₂O₃,as well as Fe₂O₃,CaO,MgO,K₂O,Na₂O,TiO₂ and MnO.The mineral components of coal gangue are kaolinite,quartz,muscovite,dolomite,small amount of calcite,illite and pyrite.It also contains a lot of organic carbon.The radioactivity of coal gangue meets the requirement of national standard for the decoration materials of class A.The fixed carbon content and calorific value satisfy the requirements for the class 3 coal gangue.Therefore,the coal gangue can be used to prepare the sintered brick,cement,lightweight aggregates and other building materials.