School of Mining Engineering, North China University of Science and Technology Hebei Provincial Lab of Mining Development and Safety Technology

为了解决近距离易自燃煤层群工作面撤架期间因通风系统不稳定、工作面停滞时间长导致采空区浮煤自燃的问题,基于回撤的一般步骤,提出了分阶段实施均压的防灭火技术:在扩大回撤通道阶段,采用调节风门与局部通风机联合均压,以提高工作面的压能,抑制外部漏风;在设备回撤阶段,采用联合调节工作面与回风巷风门有效通风面积,使得风门通风面积小于工作面有效通风面积,从而减少内部漏风。建立了分阶段实施均压防灭火前后工作面风阻的数学模型,推导了2个阶段均压调节的基本原理,给出了设备回撤阶段调压的条件。该技术成功应用于张双楼煤矿的9421综采工作面,使回撤期回风流CO体积分数从40×10-6降低至10×10-6。

In order to study the variation features of the free radical in the process of the coal low temperature oxidation, four different metamorphic degree coal sa mples were selected to the simulation experiments of the electron paramagnetic resonance and the risen temperature oxidation. The experiment results showed that the re were big differences in the free radical quantity and CO production value of coal with different metamorphic. The CO production value of the lignite was maximum an d the free radical concentration was minimum. The meager coal would be on the contrary. Thus the lower metamorphic degree of coal was, the less quantity of the free r adicals would be. In the oxidation process, the higher CO production was, the lower of the critical temperature would be and the easier of the spontaneous combustion w ould be occurred. Thus free radical concentration was found to be the index to judge the coal metamorphic degree and the oxidation progress. And the coal spontaneou s combustion oxidation process was revealed from the micro reaction.

国家自然科学基金资助项目(51374202)；