综放工作面采空区抽放注氮与遗煤自燃三耦合关系研究

为研究高瓦斯综放工作面采顶抽巷治理瓦斯和注氮与遗煤自燃三者的相互影响,寻找最佳的抽放量与注氮流量,进行实验分析;并分析了遗煤自燃抽放、注氮、温度场、O2场、CH4场影响关系图。实验表明:顶抽巷附近20 m范围内随抽放量的增加,O2浓度10%曲线逐渐向采空区延伸,采空区"三带"随之增加。受抽采半径及吸入工作面空气影响,抽放瓦斯纯度出现先增加后降低情形。随着注氮量的增加,进风侧"三带"变化浮动明显,并且对顶抽巷附近"三带"宽度也有所降低。"三带"降低率先增加后降低。81505工作面抽放量700 m³/min,注氮量2 200 m³/h时,有利于采空区防灭火。该研究为综放工作面采空区遗煤自燃治理提供参考。

Study on Coupling Relationship between Nitrogen Injection and Coal Spontaneous Combustion in Goaf of Fully Mechanized Top Coal Caving Face

In order to study the interaction among gas control, nitrogen injection and spontaneous combustion of residual coal in top coal caving face with high gas content, to find the best drainage amount and nitrogen injection flow, the experimental analysis was carried out, and the influence relationship diagram of spontaneous combustion drainage, nitrogen injection, temperature field, O2 field and CH4 field was analyzed. The experimental results show that the curve of 10% O2 concentration gradually extends to the goaf and the three zones of goaf increase with the increase of drainage volume within 20 m around the top drainage roadway. Influenced by the extraction radius and the air inhaled from the working face, the gas purity first increases and then decreases. With the increase of nitrogen injection rate, the three zone at the inlet side fluctuate obviously, and the width of three zones near the top suction roadway also decreases. The three zones decreased first and then decreased. When the pumping capacity of 81505 working face is 700 m³/min and the nitrogen injection rate is 2 200 m³/h, it is beneficial to fire prevention and extinguishing in goaf. The study provides a reference for spontaneous combustion control of goaf in fully mechanized caving face.