不同漏风条件下卸荷煤体氧化特性研究

Study on oxidation characteristics of unloaded coal under different air leakage condition

为了掌握不同漏风条件下卸荷煤体氧化特性,以便防治煤自燃火灾,采用程序升温试验研究的方法,对易自燃煤样施加相同初始应力后卸荷,通过逐渐增加风量的手段,对比了耗氧速率、CO浓度、CO产生率随煤温和漏风量的变化规律。结果显示:不同漏风条件下,卸荷煤体比原始煤样更易于氧化,各煤样氧化能力由大到小的漏风量分别为150、180、120、90、60、210、240 m L/min,且CO浓度和产生率与煤温呈指数关系;煤温一定时,CO浓度和产生率随漏风量的增加先增加后减小,漏风量达到150 m L/min时,CO浓度和变化率最大,煤样氧化能力最强。基于试验结果,将井下漏风量控制在当量流量以外,避免高温点的形成,可有效防治井下煤体自燃。

In order to master the oxidation characteristics of the unloaded coal under different air leakage conditions and to prevent and the control coal spontaneous combustion disaster,a study on a programmed temperature rise test was applied to make an unloading of the easy spontaneous combustion coal samples after a same initial stress made. With a means to steadily increase the air volume,a comparison was conducted on the oxygen consumption rate,CO gas concentration,CO production rate varied with the coal temperature and the air leakage volume. The results showed that under the condition of different air leakage,the unloaded coal would be more easily oxidized than the original coal sample. Due to the oxidation capacity of each coal sample,the air leakage volume from high to low would be 150、180、120、90、60、210、240 m L/min individually. And the CO concentration and production rate would be in an index relationship to the coal temperature.When the coal temperature is constant,the CO concentration and production rate would be firstly increased and then reduced with the air leakage volume increased. When the air leakage volume reached to 150 m L/min,the CO gas concentration and variation rate would be the maximum and the oxidation capacity of the coal sample would be the best. Based on the test results,in addition to the air leakage volume was controlled at the equivalent flow in the underground mine,to avoid a high temperature point occurred could effectively prevent and control the coal spontaneous combustion in the underground mine.