Experimental Study on Activation Method of Coal Gangue

MA Juan; YANG Junbo; YANG Liu

doi:10.19698/j.cnki.1001-6171.20253071

Abstract：Coal gangue contains a certain proportion of kaolinite and can be used as a cement admixture,but its volcanic ash activity is extremely low,leading to poor utilization.To improve the utilization rate of coal gangue,elemental analysis,phase analysis,and TG-DSC thermal analysis were conducted to compare the alkali content,kaolinite content,and heat release enthalpy of coal gangue and kaolin from different origins.The study also investigated the effects of calcination temperature,grinding fineness,and kaolinite content on the volcanic ash activity of coal gangue.The results show that at a calcination temperature of about 1 000℃,the heat release enthalpy of coal gangue is positively linearly related to the kaolinite content;different calcination temperatures and origins of coal gangue have varying contributions to the 3d and 14d volcanic ash effect strength;grinding fineness significantly affects the 3d and 14d volcanic ash activity of coal gangue;the higher the iron content in coal gangue,the redder the calcined coal gangue becomes,which negatively impacts its application in cement.In industrial production,thermal analysis should be used to qualitatively predict the volcanic ash activity of coal gangue,experimental determination of the optimal calcination temperature and grinding fineness is necessary,and tests should be conducted to determine whether there are under-fired or over-fired conditions in coal gangue,with a preference for using coal gangue with lower iron content as raw material.