南屯煤矿综采工作面煤自燃分级预警体系研究

Study on Grading Early Warning System of Coal Spontaneous Combustion at Fully Mechanized Mining Face of Nantun Coal Mine

采空区内煤自燃隐患监测预警,是煤自燃火灾早期预防的前提和亟待解决的关键难题。建立煤自燃分级预警体系,是为了解决南屯煤矿工作面回采过程中煤自燃火灾的监测预警问题。采用煤自燃程序升温实验得到了南屯煤矿综采工作面煤样在采空区不同氧气浓度下自燃氧化过程中耗氧速率、CO气体、C_(2)H_(4)等氧化气体随温度的变化规律,结合现场数据,经过优选确定了CO,O_(2),C_(2)H_(4)及C_(2)H_(6)作为主要的工作面采空区煤自燃预测指标气体,并辅以格氏火灾系数R_(2),R_(3)与φ(C_(2)H_(4))/φ(C_(2)H_(6))作为煤自燃隐患的预测预警指标。提出了南屯煤矿综采工作面“灰、蓝、黄、橙、红、黑”6级预警指标体系,结合现场确定了预警阈值,形成了综采工作面煤自燃分级预警指标体系。在综采工作面煤进行了应用,实现了煤自燃隐患的早期预警,提高了煤自燃火灾防控的技术水平,保障了工作面的安全回采。

The monitoring and early warning of coal spontaneous combustion(CSC)in the mining area is a prerequisite for the early prevention of CSC fires and a key challenge to be solved.The grading and warning system of CSC was established to solve the problem of monitoring and warning of CSC fires during the back mining process at the working face of Nantun coal mine.The experiments of CSC temperature rise were used to obtain the change of oxygen consumption rate,CO,C_(2)H_(4) and other oxidation gases with temperature during oxidation process in Nantun coal mine workings at different oxygen concentrations in the mining area.In addition,combined with the field test data,CO,O_(2),C_(2)H_(4) and C_(2)H_(6) were preferentially identified as the main working face CSC prediction index gases in the mining void area.This is supplemented by the Grignard fire coefficients R_(2),R_(3),and φ(C_(2)H_(4))/φ(C_(2)H_(6)) as the predictive warning indicators of CSC hazards.Finally proposes a six-level warning index system of“grey,blue,yellow,orange,red and black”for the comprehensive mining working face in Nantun coal mine,and determines the warning threshold value in combination with the site,forming a graded warning index system for CSC at the comprehensive mining working face.The system was applied in the coal mining face,which realized the early warning of the potential CSC,improved the technical level of CSC fire prevention and control,and ensured the safe recovery of the working face.