大南湖一矿褐煤常温氧化特性研究

Research on Ordinary Temperature Oxidation Characteristics of Lignite in Dananhu No.1 Mine

针对大南湖一矿在正常回采期间、采空区在无任何自燃征兆前提下出现的上隅角CO异常持续超限问题,采用太原理工大学自行研制的常温氧化实验装置对所采煤样褐煤开展了常温氧化特性研究。结果表明:大南湖一矿褐煤在常温下就可氧化释放出CO,相关过程可分为“快速氧化”“缓慢反应”和“反应终止”三个阶段;当环境O_(2)浓度≥7.7%时,大南湖一矿煤样常温下氧化的CO产出速率同环境O_(2)浓度呈二次函数拟合关系;大南湖一矿煤样环境CO浓度同O_(2)浓度变化紧密相关,呈良好一次函数关系;大南湖一矿褐煤开采过程中煤自燃早期预警指标的制定必须考虑常温氧化特性,否则可能会误判采空区煤自燃的严重程度。

In view of the problem of abnormal continuous exceeding limits of CO in the upper corner of the goaf without any signs of spontaneous combustion during the normal stoping period in Dananhu No.1 Mine,a ordinary temperature oxidation experimental device independently developed by Taiyuan University of Technology is used to conduct a study of ordinary temperature oxidation characteristics of the extracted coal sample of lignite.The results show that the lignite in Dananhu No.1 Mine can oxidize and release CO at ordinary temperature,and the related process can be divided into three stages:"rapid oxidation","slow reaction",and"reaction termination";when the environmental O_(2) concentration is≥7.7%,the CO production rate of coal sample oxidation at ordinary temperature in Dananhu No.1 Mine shows a quadratic function fitting relationship with the environmental O_(2) concentration;the environmental CO concentration in the coal sample of Dananhu No.1 Mine is closely related to the variation of O_(2)concentration,showing a good linear function relationship;the early stage early warning index of coal spontaneous combustion in the process of lignite mining in Dananhu No.1 Mine must consider the normal temperature oxidation characteristics,otherwise the degree of severity of coal spontaneous combustion in goaf may be misjudged.