为了防止胶结充填开采中充填体凝固过程放热引起相邻煤体自燃风险,分别进行了井下充填体温度场实测和煤自燃指标气体试验.在风积砂似膏体连采充填工作面支巷1 386 m3充填体内部、与外部交界面及相邻煤体不同位置设置了16个测点,进行了为期50 d的充填体水化温度场监测,结果表明:温度变化分为“快速上升”、“较快下降”和“缓慢下降”3个阶段,94～ 98 h内部温度达到峰值63.5 ～ 64.4 ℃,水化温度持续时间约30 d;相邻煤体受水化热影响深度约0.5 m.实验室自燃指标气体(CO、C2H4和C3H8)试验表明,受充填体水化热影响的煤样指标气体生成的初始温度低于常规煤样,且相同温度下前者指标气体浓度大于后者,表明前者更容易自燃.研究表明胶结充填采空区煤体自燃风险不容忽视.%In order to prevent the spontaneous combustion risk of adjacent coal bodies during solidification process of filling body in cemented backfill mining,a site measurement of the temperature field as well as the index gas test of the coal spontaneous combustion were individually conducted.There were 16 measuring points set in different locations,as the 1 386 m3 backfilled mass of the branch gateway in the aeolian sand paste-like backfill continuous mining face,the interfaces connected with the external and the neighboring seam.A 50 days monitoring and measurement was conducted on the hydrated temperature filed of the backfill mass.The results showed that the temperature variation could be divided into three stages,including "a rapid rising","quick declining" and "gently declining".After 94～98 h,the internal temperature would reach the peak value of 63.5 ～ 64.4 ℃.The hydrated temperature lasted time would be about 30 days.The depth of the neighbor seam affected by the hydration heat was about 0.5 m.The lab test of the spontaneous combustion index gas (CO,C2H4 and C3H8) showed that,affected by the hydrated heat of the backfill mass,the initial temperature generated from the index gas of the coal samples would be lower than the conventional coal samples.Under the same temperature,the index gas concentration of the coal sample affected by the hydrated heat would be higher than the conventional coal samples,and this indicates that the coal sample affected the hydrated heat would be easy to be spontaneously combusted.The research showed that,the spontaneous combustion risk of the coal in the cemented backfill goaf could not be ignored.
展开▼
