摘要：For further understanding of self-heating of coal,we tested the reactions of seven different ranks of coal under inert *** the test,50-gram of coal sample ranged from 0.18 mm to 0.38 mm was put into a special designed copper reaction vessel and let pure nitrogen to flow into the coal sample from the bottom at a rate of 100 mL/*** programmed temperature enclosure was run at a programmed rate of 0.8 °C/*** concentration of the carbon oxides and the coal temperature were *** results show that the coal reactions under inert atmosphere can generate CO and *** reactions under inert atmosphere are affected by coal ranks,initial pore structure of coal and sulfur *** low ranks of coal,the productions of carbon oxides are *** coal temperature is lower than the surrounding temperature throughout the reactions under inert atmosphere,but it rises quickly and reaches a crossing point temperature in the later stage under dry-air *** on the analysis,it indicates the self-reaction of initial active groups exists in the self-heating of coal besides the reactions in the two parallel reactions *** combustion of coal is due to both the oxidation heat accumulation and the chain reaction.A new reaction model of self-heating of coal was proposed.

摘要：进一步的理解煤自我加热被调查煤的不同等级的交叉的点温度(CPT ) 获得。测试为煤用一个自我设计的试验性的系统被执行自我加热。50 g (???

摘要：大规模高强度回采和深部开采常导致顶部裂隙煤岩体失稳、漏风及其次生灾害。钻孔注浆是封堵裂隙和加固煤岩体的主要手段之一。由于煤岩裂隙高位注浆研究相对滞后,井下高位注浆施工设计缺少足够的依据。为探究煤岩裂隙高位注浆浆液扩散规律,以任意倾斜有限边界的光滑平板裂隙和宾汉流体为研究对象,建立裂隙高位注浆扩散数学模型并进行数值模拟求解,分析不同裂隙倾角和注浆速率下浆液在裂隙流动过程中的扩散锋面、流量分配及压力场变化规律;在此基础上,建立浆液高位流动数学模型,并推导恒定注浆速率工况下的解析解。研究结果表明:根据扩散锋面的演变规律,浆液流动过程可分为自由扩散阶段、过渡阶段和受限堆积阶段3个阶段。裂隙倾角对高位扩散距离的影响程度随着流动阶段的演化逐渐减小,注浆流速对高位扩散距离的影响程度随着流动阶段的演化逐渐增大。过大的裂隙倾角加大了高位流量的损耗并加快了流动阶段的转变,而过大的注浆速率减缓了高位流量的损耗并加快了流动阶段的转变。注浆速率和裂隙倾角的增大均会导致注浆压力增加,且在浆液进入受限堆积阶段后注浆压力发生突变。以高位流动扩散形态的等效圆半径临界状态为界,高位流动可划分为扩散阶段与堆积阶段,不同阶段内反演得出的等效圆心角与注浆速率、裂隙倾角和注浆时间具有较好的相关性。根据对比分析结果,浆液高位流动数学模型中相对误差低于20%的样本占97%,相对误差低于10%的样本占78.4%,表明浆液高位流动数学模型具有一定的合理性。浆液在不同时间段内向高位裂隙深部扩散的范围受到裂隙边界影响,只有当底部裂隙空间被填充完毕后浆液才会在裂隙边界的支撑下向深部堆积,因此在现场高位注浆设计时应先探明裂隙区域的边界范围。针对上覆煤岩表层区域范围的裂隙封堵时可采用较低的注浆速率以延长自由扩散阶段时长,实现底部裂隙空间的快速封堵。对煤岩裂隙深部区域进行注浆充填时可先使用较高的注浆速率进行注浆,当压力表发生突变后表明浆液已进入受限堆积阶段,此时可降低注浆速率,使注浆压力控制在安全可控范围内。

摘要："矿井通风与安全"是采矿工程和安全工程的核心课程之一。该课程的前期教学过程中,一般采用传统式的教学方法开展课堂教学,缺乏与学生之间的充分研讨、交流,缺乏启发式、互动式的教学效果。基于这一现状,我们近年来开展了该课程的研讨式教学方法设计与实践。教学效果表明,研讨式教学法为学生提供了更多的互动和研讨环节,提高了学生在教学过程中的参与度,显著提高了教学效果和学生对知识的把握程度,效果十分明显。本教学实践能够为同类课程和其他相关课程的教学过程提供借鉴。