摘要:
煤矿采空区煤自燃高温区域可能导致甲烷/煤尘爆炸，有必要开展煤自燃诱发瓦斯/煤尘爆炸的研究。目前基于电火花诱发方式对瓦斯/煤尘爆炸特性的研究不能充分反映采空区内煤自燃诱发瓦斯/煤尘爆炸的特性，针对该问题，利用自主研制的40 L气体爆炸设备研究在高温热源表面点火方式下甲烷/煤尘爆炸特性。结果表明：① 通过高温热源表面点火方式得到的甲烷/煤尘爆炸过程与甲烷/空气爆炸过程一致，均可分为3个阶段。② 甲烷/煤尘的3个爆炸参数(爆炸压力、压力上升速率和爆炸温度)随甲烷浓度的变化规律一致，即先随着甲烷浓度的增加而升高，达到峰值后随甲烷浓度的增加而降低；当甲烷浓度小于转折浓度时，甲烷/煤尘的3个爆炸参数分别大于甲烷/空气相对应的爆炸参数；当甲烷浓度大于转折浓度时，甲烷/煤尘的3个爆炸参数分别小于甲烷/空气相对应的爆炸参数；由于煤尘的加入，甲烷/空气的3个爆炸参数的转折体积分数由115%分别降至95%，105%和95%，峰值分别增加了08%，69%和08%，且规律性下降。③ 由于点火方式不同，爆炸温度的变化规律不同：电火花引爆甲烷/煤尘后爆炸温度在下降阶段(Ⅲ阶段)再次出现升高的现象；高温热源表面引爆甲烷/煤尘后爆炸温度变化规律与未加入煤尘时保持一致。④ 对煤尘点燃温度预测函数进行了修正，修正后的拟合优度提高了2005%；结合实验数据得到了煤尘在高温热源表面点火方式下的点燃温度预测函数。
Abstract:
The high temperature area of coal spontaneous combustion in coal mine goaf may cause methane/coal dust explosion. Therefore, it is necessary to carry out research on coal spontaneous combustion induced methane/coal dust explosion. The current research on the characteristics of methane/coal dust explosion based on the electric spark induced method cannot fully reflect the characteristics of methane/coal dust explosion induced by coal spontaneous combustion in the goaf. In order to solve this problem, the self-developed 40 L gas explosion equipment is used to study methane/coal dust explosion characteristics under the high temperature surface ignition of heat source. The results are showed as follows. ① The methane/coal dust explosion process obtained by the surface ignition method of the high-temperature heat source is consistent with that of methane/air explosion, which can be divided into 3 stages. ② The three explosion parameters of methane/coal dust (explosion pressure, pressure rise rate and explosion temperature) are consistent with the change law of methane concentration, that is, the parameters first increase with the increase of methane concentration, reach a peak and then decrease with the increase of methane concentration. When the methane concentration is less than the turning concentration, the three explosion parameters of methane/coal dust are greater than the corresponding explosion parameters of methane/air respectively. When the methane concentration is greater than the turning concentration, the three explosion parameters of methane/coal dust are less than the corresponding explosion parameters of methane/air respectively. Due to the addition of coal dust, the turning concentrations of the three explosion parameters of methane/air decrease from 11.5% to 9.5%, 10.5% and 9.5% respectively, and the peak values increase by 0.8%, 6.9% and 0.8% respectively, and decrease regularly. ③ Due to the different ignition methods, the explosion temperature change law is different. The explosion temperature rises again in the falling stage (stage III) after the methane/coal dust is detonated by the electric spark. The explosion temperature change law after detonation of methane/coal dust on the surface of high-temperature heat source remains the same as that before the addition of coal dust. ④ The coal dust ignition temperature prediction function is corrected, and the goodness of fit is improved by 20.05% after correction. Combined with the experimental data, the ignition temperature prediction function of coal dust in the ignition mode of the high temperature heat source surface is obtained.
百度学术
下载:
