大采高工作面回风隅角CO来源分析及定量表征

Analysis and quantitative characterization of sources of CO in the return air corner of large mining height working face

大采高工作面具有漏风量大、遗留煤柱易堆积蓄热以及井下胶轮车使用频繁等问题,极易导致回风隅角CO浓度超限,不仅严重威胁工作面安全回采,还干扰采空区煤自燃险情的判断,因此,准确、及时研判回风隅角CO来源成为大采高工作面采空区煤自燃防治的当务之急。以CO的产生机理为理论依据,分析了大采高工作面回风隅角CO来源及影响因素,量化了各因素对回风隅角CO浓度的影响,建立了回风隅角CO浓度计算模型,并利用该模型预测了察哈素煤矿不同工作面的回风隅角CO浓度。预测结果与实测值的相对误差小于4.4%,说明该模型可准确预测回风隅角CO浓度,判断CO主要来源,对及时消解回风隅角CO浓度超限问题、准确掌握采空区煤自燃情况具有重要指导意义。

Large mining height working face has many problems such as large air leakage,easy accumulation of heat in coal pillars and frequent use of underground rubber wheels.It is very easy to cause the concentration of CO in the return corner to exceed the limit,which not only threatens the safe mining of the working face,but also interferes with the judgment of the risk of spontaneous combustion of coal in the goaf.Therefore,accurate and timely analysis of the source of CO in the return air corner has become an urgent task for the prevention and control of coal spontaneous combustion in goaf areas with high mining height.Based on the theory of CO generation mechanism,this paper analyzed the source and influence factors of CO at the return air corner of the large mining height working face,quantified the influence of various factors on the CO concentration at the return air corner,established a calculation model for the CO concentration at the return air corner,and used this model to predict the CO concentration at the return air corner of different working faces in Chahasu Coal Mine.The relative error between the predicted result and the measured value is less than 4.4%,which indicates that the model can accurately predict the CO concentration at the return air corner,judge the main source of CO,and has important guiding significance for resolving the problem of CO concentration overrun at the return air corner in time,and accurately grasp the spontaneous combustion of coal in the goaf.