摘要
为了防治易自燃大采高工作面自然发火,采取采空区注二氧化碳抑制遗煤氧化自燃。通过数值模拟与束管监测相结合的方法,研究了采空区注二氧化碳前后的自燃区域分布规律。数值模拟结果表明,采空区进风侧自燃带最宽,更容易发生煤自燃,注二氧化碳后自燃区域显著减小。其中,压注口距工作面20 m时,采空区中部和回风侧自燃区域分别减小68 m和65 m;距工作面40 m时,采空区进风侧、中部和回风侧自燃区域分别减小50 m、50 m和61 m;距工作面60 m时,采空区进风侧自燃区域减小82 m。模拟结果和现场观测结果一致,证明了注二氧化碳可显著减小自燃危险性区域。
In order to prevent the spontaneous combustion in the gob, it is a common practice to spray the carbon dioxide steam to impede the coal oxidation and its consequential spontaneous combustion. In this paper, we would like to make an exploration of the distribution regularity on how for the spontaneous combustion to take place in such zones before and after the carbon dioxide injection via a numeri- cal simulation along with the available means of tube monitoring. For our research purpose, we have chosen the testing samples of 10% of the oxygen concentration to determine the zones in the gob of easy self-ignition and large-scale mining panel. Before the carbon dioxide injection, a pretest of the numerically simulated samples can be done, which can help to indicate that the spontaneous combustion zones on the side of the air intake, middle and the air return point may occupy respectively in the distances of 122 m, 89 m and 92 m farthermost from the working face with the air volume of 2 800 m3/min. The tube monitoring results show that the air intake and air return zones respectively are 130 m and 87 m from the working face, which forms the main spontaneous combustion zone, which is by na- ture the widest zone in the gob and most liable to self-ignition. Thus, it can be seen that our numerical simulation results turn to be well in accord with the tube monitoring results. The next step we have taken is that, based on the numerical results, we have worked out the dis- tribution regularity of the spontaneous combustion zones in accordance with the carbon dioxide injection. For example, if the width of the middle and air return parts of the spontaneous combustion zones tend to be reduced to 68 m and 65 m, respectively, the air intake and re- turn zones could be further narrowed down to 22 m in case the injec- tion width is 20 m from the working face. On the~ other hand, when the air intake and return zones tend to decrease by 50 m and 61 m, the middle part of the air intake and return zones would be expected to reduce by 50 m when the injection hole is 40 m from the working face. And, in turn, when the zone of the air intake may reduce sig- nificantly to 82 m, the middle and air return zones are likely to de- crease by 26 m and 17 m, respectively, in case the injection strip is 60 m from the working face. Based on the tube monitoring results, it can be found that the spontaneous combustion zone of the air intake may decrease from 122 m to 66 m and the zone of air return decreases from 89 m to 32 m. The research findings prove that the carbon diox- ide injection can help to reduce the spontaneous combustion liability significantly and provide some theoretical bases for determining the injection parameters.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2016年第1期29-32,共4页
Journal of Safety and Environment
基金
安徽省科技攻关项目(12010402110)
安徽建筑大学博士启动基金项目
关键词
安全工程
煤矿防火
注二氧化碳
采空区自燃
自燃区域
易自燃
safety engineering
fire prevention of coal mine
carbon dioxide injection
spontaneous combustion in gob
spon-taneous combustion zone
easy self-ignition
