Comparative experiment on fluidity of grinded coal gangue and loess grouting materials
Coal gangue(CG) disposal is becoming a problem seriously restricting sustainable development of coal industry. Using CG grinding powder materials instead of loess for grouting in goaf can achieve large-scale consumption of CG. Firstly,the grouting flow properties of CG powder and loess were compared and studied. Secondly,the fluidity of coal gangue powder grouting materials was optimized by adjusting the dosage of four solid waste additives,including desulfurization gypsum,fly ash and gasification slag. Thirdly,the influence of sodium lignosulfonate water reducer and naphthalene series water reducer on the fluidity of CG grouting at different dosage was analyzed. Finally,based on the engineering background of Daliuta Coal mine,the optimal material ratio of grouting fluidity was determined. The results show that the particle size of coal gangue powder is fine as a whole,and its grouting fluidity is lower than that of ordinary loess materials. Adding solid waste additives can improve the fluidity of coal gangue grinding materials. Desulfurization gypsum as solid waste additives has the most obvious improvement effect,with the improvement range reaching 19.28％. When the mass fraction of coal gangue,fly ash and desulfurized gypsum are 60％,10％ and 30％,respectively,and the sodium lignosulfonate water reducer accounts for 0.5％ of the total solid mass,the prepared coal gangue grouting materials with 50％ mass fraction has the best fluidity.
万方数据
维普
