为了研究挥发分对煤尘爆炸的影响,利用FCY-Ⅱ粉尘云最低点火能测定仪和水平玻璃管煤尘爆炸试验系统,测定了不同挥发分含量的煤尘爆炸最小点火温度和爆炸产生的最大火焰长度,分析了挥发分对煤尘爆炸最低点火温度影响,即通常情况下挥发分含量越大,最低点火温度越高,个别煤样不符合此规律,是因为水分含量过高,对煤尘爆炸起到抑制作用.选用合适的湍流及燃烧的数学理论模型,应用CFD软件模拟不同挥发分含量下煤尘爆炸的最大火焰长度,模拟结果与试验数据比对,误差均＜20％,说明数值模拟结果可靠,模拟手段可行,为划分爆炸等级和制定防爆措施提供参考依据.

寺河矿当前采用分区通风方式,由3个进风井和3个回风井组成,通风系统复杂.随着生产的持续,出现1#回风井所在分区通风系统风量利用率低、电力消耗较大、风机低压供电不稳定和2#回风井所在通风区域巷通风距离长、阻力大、通风能力近饱和等问题,整个矿井安全可靠性较差.通过对矿井进行通风参数测试与数据处理、通风系统网络普查,构建了通风仿真解算网络,从通风系统阻力合理性、矿井各用风地点风量供需对比、三区阻力分布和公共进风路线对风机工况扰动等角度详细分析了当前通风系统存在的具体问题.对主干风路(3个进风井和3个回风井)的过风能力和各用风点的需风量进行了核定,根据总进风量满足生产需求且总进风量与总回风量相匹配的原则,提出将当前3#进风井变为回风井、将1#回风井和2#回风井变为进风井的改造方案,即将"三进三回"通风系统改造为"四进两回"通风系统.对改造后的通风系统重新进行了盘区划分,按照选定的最优盘区划分方案对"四进两回"通风系统进行了调整,最终总回风量达到17743.2 m3/min,回风量增加,总阻力降低,各用风点的风量满足要求,系统阻力分布合理,风机能耗降低.

为构建合理通风系统,降低事故发生的可能性,基于AutoCAD二次开发研发了通风智能决策支持系统,以基于节点压能的网络分风算法及风量反演风阻算法为核心,论述了算法的先进性及可行性,给出了算法原理.软件的主要功能模块包括拓扑分析模块、数据检查模块、网络解算模块、数据分析模块、掘进通风模块,能够满足技术人员对通风系统模拟及优化的需求,能够为通风问题的解决提供技术支持.

In order to study the variation law of coal dust explosion pressure with different metamorphic degrees, the maximum pressure pmax and maximum pressure rise rate (dp/dt)max are characterized. The variation of explosion pressure characteristics of lignite, long flame coal, non-coking coal and gas coal is investigated by using a near-spherical coal dust explosion device. It is found that, among the selected coal dust samples, lignite has the largest pmax and (dp/dt)max, up to 0.71 MPa and 65.69 MPa/s, respectively. With the increase of metamorphism, the pmax and (dp/dt)max of long-flame coal, non-coking coal and gas coal are significantly reduced. Characterizing the explosion intensity by the explosion pressure characteristics, the four coal dust explosion strengths are then ranked from lignite, long flame coal, non-coking coal to gas coal. By comparing the volatile matter content of coal dust before and after the explosion, it is concluded that the proportion of volatile matter involved in the explosion is 46.28%−68.19%. At dispersion pressure p0=2.0 MPa and ignition delay time t0=100 ms, the pmax values of the four types of coal dust reach the maximum 0.71, 0.60, 0.55 and 0.47 MPa, respectively. However, lignite, non-viscous coal and gas coal have the highest (dp/dt)max at p0=2.0 MPa and t0=80 ms, while long-flame coal reaches the maximum (dp/dt)max at p0=2.0 MPa and t0=100 ms. The results are of significance for mastering explosion pressure characteristics under different test conditions.

为研究煤尘层最低着火温度随煤样变质程度、煤尘粒径及煤尘层厚度的变化规律,采用煤尘层最低着火温度测定系统进行实验研究,结果表明:随着煤样由褐煤到无烟煤变质程度逐渐增大,煤尘层最低着火温度由290℃上升到400℃以上,同时,褐煤、长焰煤、不粘煤、气煤煤尘层着火时观察到明显的火焰.随着煤尘粒径不断减小,不同煤质的煤尘层最低着火温度明显减小,煤尘层厚度为15 mm时,随着煤尘粒径由0.5 mm减小至0.075 mm,不同煤质煤尘层最低着火温度分别减小了31.0％、26.7％、28.1％、25.8％、28.6％、27.8％、18.9％和15.0％,煤尘粒径影响作用十分显著.随着煤尘层厚度的增大,不同煤质在不同粒径下的煤尘层最低着火温度都减小,其中无烟煤的变化最不明显.

In order to solve the problems of high dust concentration and low visibility in the tunneling, and achieve the pur-pose of improving the operating environment and reducing the harm to the workers, a kind of adjustable biconical integrative device for dust control with foam was developed based on the vortex and jet principles of fluid mechanics, and the optimal technical principle, design structure and operation methods of the device were determined by many times of simulation experi-ment.The gas-liquid two-phase control panel was designed depending on the system adjustment component, so as to achieve the adjustment and monitoring on the gas-liquid ratio.The results showed that the adjustment on gas-liquid ratio could be re-alized by adjusting the valve in the process of dust control with foam, and the continuous and homogeneous foam could be produced.The optimum concentration of vesicant was 2.5%, and the deposited liquid could be recycled by the foam recy-cling device.The efficiency of dust control for the total dust and respirable dust reached 93.4%and 90.2% respectively, which showed a comprehensive and tridimensional effect of dust control.The device can achieve the efficient dust control at the fully mechanized tunneling face of mine, and control the foam account and particle size accurately, then achieve the con-trol of dust source with different particle sizes in different mine.

针对回采工作面瓦斯涌出治理面临的通风和抽放问题,在某示范矿井2307、3308两个工作面分别进行了综放面内错尾巷和采空区顶板走向长钻孔技术的工业试验.通过分析两项技术的实施效果,得出内错尾巷技术和顶板走向长钻孔技术能够有效遏制上隅角瓦斯超限和工作面瓦斯涌出,减少通风负担.指出了内错尾巷试验中存在的问题,并提出了相应的尾巷布置改造建议;给出了顶板走向长钻孔抽放技术钻孔布置的合理有效的参数.最终肯定了内错尾巷、顶板走向长钻孔技术治理瓦斯的可行性.

Taking the coal mine safety as the main purpose and taking the mine's man-machine-environment system as the object of study,the safety factors affecting the mine's man-machine-environment system have been systematically analyzed.Based on the actual status of the coal mine,the safety assessment index system of mine is established.Using the fuzzy set-value statistical theory,the method to determine appraisal index weight value of the man-machine-environment system is given,and reliability of the weight is analyzed.