高突厚煤层高位钻孔抽放技术参数优化

为了准确分析高位钻孔的效果,基于高位钻孔瓦斯抽放理论,在工作面高位钻场每个钻孔安置1个孔板流量计和1个测气孔,根据工作面的进尺实测每个钻孔管路上的流量和瓦斯浓度,并通过计算得到该钻孔的瓦斯混合流量和瓦斯纯量。分析抽放钻孔各种参数并进行优化,得出高效合理的高位抽放钻孔布置方式。     

采场动压分布特征及高效瓦斯抽放技术研究

河南地区大部分煤矿所采煤层均属于三软煤层,煤层透气性差,瓦斯治理困难。现阶段河南区域煤与瓦斯突出矿井主要采用穿层钻孔及开采保护层作为区域防突措施,而低瓦斯矿井或临突矿井（低瓦斯矿井与煤与瓦斯突出矿井相邻）存在高瓦斯区时,仅仅用风排瓦斯很难达到治理效果,近些年煤矿发生瓦斯事故多数为低瓦斯矿井,所以低瓦斯矿井和临突矿井存在高瓦斯区域的工作面回采期间瓦斯治理尤为重要。根据采场“竖三带”和“横三区”理论,利用钻孔抽放效果考察法和工作突出预测指标法研究了采场围岩动压分布特征。在此基础上,通过优化动压区抽放钻孔设计,提高了瓦斯抽放效果。瓦斯抽放量提高了1.8倍,有效降低了工作面生产期间的风排瓦斯量,提高了生产效率,保证了矿井安全生产。     

前和煤业东胶带运输大巷钻孔卸压围岩控制技术

为有效解决前和煤业3#煤层东胶带大巷在原有锚网索支护下围岩变形量大的问题,结合巷道变形特征,确定采用钻孔卸压技术,采用理论分析和数值模拟的方式确定卸压钻孔在修巷作业前,垂直于巷帮打设,钻孔深度为8 m,结合巷道的具体条件确定巷道采用卸压钻孔+让压支护的围岩控制方案,并采用矿压监测验证支护效果。结果表明:支护方案实施后,顶底板和两帮的最大移近量分别为141 mm和132 mm,有效解决了巷道两帮及底板鼓起量大的问题,保证了巷道围岩的稳定性。     

Field investigation of using water injection through inseam gas drainage boreholes to control coal dust from the longwall face during the influence of abutment pressure

Coal dust is a primary contributor to underground coal-mining disasters and is also a major factor in adversely affecting the occupational health of mine workers. Pre-wetting the coal seam with water injection is widely considered as one of the effective means of mitigating coal dust generation during mining. Injecting water through inseam long boreholes parallel to the working face is a commonly used technique. However, for most fully-mechanised top-coal caving working faces, inseam gas drainage boreholes are drilled to extract gas from the gassy seam prior to mining. Therefore, there is neither enough time nor space at the working site for an elaborated water injection process. Based on the mining conditions at Panel 9801 of the Yangquan coalfield, this study designed a water injection system through the inseam gas drainage boreholes to control dust arising from the longwall face. Under the influence of abutment pressure, water injection through a set of inseam gas drainage boreholes was experimentally investigated to offset the conflict between water injection and gas drainage in terms of the time and space availability. The relations between the amount of injected water, the injection rate, the seam moisture content and the coal dust level at the working space were investigated. The effect of water injection for dust control at different distances ahead of working face was assessed. With the change of abutment pressure, the effect of water injection to inseam gas drainage and gas emission at working face was revealed and a space-time balance between gas drainage and dust control by water injection was established. The results indicate that under the influence of abutment pressure, water injection through inseam gas drainage boreholes wetted the seam and decreased the dust level at the working face. Water injection only has marginal influence on inseam borehole drainage and has a negligible impact on the gas level produced at the working face. Under the influence of abutment pressure, the optimum area for water injection through the inseam boreholes was the primary fracture opening zone and the secondary fracture development zone.     

千米埋深特厚煤层井筒揭煤综合防突技术

为解决千米埋深特厚煤层立井揭煤防突和穿煤施工安全,通过建立区域突出危险性预测、深孔预裂控制爆破增透抽放、效果检验和验证、中空锚杆金属骨架、远距离放炮揭煤、突出危险性预警和壁后预留排放等组成的七步法综合防突技术,从技术、施工组织、工程质量和安全防护4个环节保障施工安全。结果表明：采用深孔预裂控制爆破强化措施,抽放41 d达到区域防突要求;采用2圈中空锚杆注浆加固和壁后预留1圈排放孔等新工艺,揭煤和穿煤期间瓦斯浓度非常稳定,实现了零超限揭穿千米埋深9.8 m厚突出煤层。     

深井煤巷卸压孔与锚网联合支护的模拟与实践

为了解决深井高应力煤巷支护成本与支护效果之间的矛盾,提出并研究了卸压孔与锚网联合支护技术．结合一个工程实例,采用数值方法模拟和分析了钻孔卸压的作用机理、巷道围岩动态损伤破坏发展以及围岩中应力场重新分布的过程．研究表明：合理布置的卸压孔可以引起巷帮围岩发生结构性预裂破坏,从而使围岩内高应力向深部转移;卸压孔和锚网联合支护改善了围岩中的应力环境,改变了围岩破坏的时空次序,对控制围岩变形和破坏具有突出的优越性．将模拟结果用于指导具体的施工,不仅控制了围岩的变形,而且降低了材料消耗,取得了较好的综合效益．     

采用超前钻孔注浆过破碎区的支护技术

针对矿山压力较大矿井存在一旦暴露就易垮落的松散围岩,采用快速有效的超前钻孔注浆加固,形成再生假顶,从而实现调动围岩自承力的内注外锚加固技术,是一种安全上可靠、技术上可行、经济上合理、较强,推广前景远的支护技术。     

爆破动载下强冲击危险巷道锚杆轴力定量损失规律的试验研究

针对目前冲击地压矿井卸压爆破参数常不合理导致支护损伤,降低防冲效果的问题,采用锚杆无损检测系统在井下强冲击危险巷道进行现场原位试验研究,定量化分析了爆破动载下锚杆轴向工作阻力的定量损失规律。通过分析,获得了不同药量的爆破导致锚杆轴力损失的影响程度及空间范围。发现了爆破药量不小于6 kg时,随至震源距离的增大锚杆轴力的平均损失率基本呈乘幂关系衰减,但也存在局部突增的可能。同时爆破下锚杆轴力损失是与锚杆方位相关的,距震源越近与锚杆方位的相关性越显著。随着爆破药量的增大锚杆轴力损失率升高,药量越大升高速度越快。通过分析发现,众多影响因素中至震源的距离和锚杆方位只是表层因素,而爆破药量和煤体性质才是核心因素,并且核心因素间也存在相互影响。综合考虑爆破下锚杆轴力损失规律以及煤层爆破的卸压效果,优化了内蒙某矿强冲击危险巷道爆破卸压参数,现场应用效果理想。由此建立了冲击地压矿井煤层卸压爆破参数优化的现场原位试验方法。     

考虑卸压和抽采效果的水力冲孔布孔参数优化研究

为了提高水力冲孔技术的消突效果,建立了考虑煤的塑性软化、扩容特性和流变特性的钻孔周围煤体黏弹塑性模型,得到了不同冲煤量钻孔的卸压范围,建立了考虑渗透率动态变化和吸附特征的渗流-应力耦合模型,采用COMSOL软件对建立的耦合模型进行求解,研究了不同冲煤量钻孔的抽放半径,优化了水力冲孔布孔参数。结果表明:在确定水力冲孔布孔参数时,应综合分析水力冲孔的卸压范围和抽放半径,冲煤量为0.5,1.0和1.5 t/m时,卸压范围分别为3.71,4.61和5.8 m,抽放半径分别为3.5,4.3和5.0 m,义安矿平均冲煤量为1.0 t/m,由此确定水力冲孔布孔间距为8.0 m,区域措施效果检验和工作面预测数据表明,确定的布孔参数合理可靠。     

放顶煤开采顶板瓦斯抽排钻孔的应用研究

上隅角瓦斯超限是放顶煤开采遇到的主要安全问题 ,除采用E型通风方式外 ,在较薄煤层布置专用瓦斯排放巷困难时 ,可以采用顶板纵向钻孔抽排瓦斯。本文通过实验室模拟和现场实践研究 ,进行了钻孔的合理参数和实验效果的分析 ,其结论对放顶煤开采的瓦斯防治有借鉴和指导作用