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1.
兴安煤矿对煤层顶板坚硬,工作面倾向较短,后部空区不易冒落的高瓦斯采煤工作面,采用仰斜钻孔、上隅角插管、底板巷道穿层钻孔抽放采空区等综合治理瓦斯技术,仍存在上隅角瓦斯超限隐患。本文以采煤一队为例阐述利用外错尾巷抽放进行瓦斯综合治理,防止了高瓦斯采煤工作面上隅角瓦斯超限。  相似文献   

2.
通过开采下覆煤层综采工作面对上覆采空区瓦斯的规律分析;在下覆煤层综采工作面预采前,采取控制排放上覆采空区瓦斯的有效措施,合理布置抽放钻孔,有效遏制上覆采空区瓦斯向下覆综采工作面的涌出,确保安全生产。  相似文献   

3.
作者采用仰斜钻孔安设透气套管对松软煤层内的瓦斯进行抽放。通过实施抽放,解决了该工作面瓦斯超限问题,保证了该工作面在瓦斯不超限的情况下安全顺利开采。  相似文献   

4.
本文介绍兴安煤矿综采二队开采布置采用井下穿层钻孔或顺层钻孔预抽区段煤层瓦斯、穿层钻孔预抽煤巷条带煤层瓦斯、顺层钻孔或穿层钻孔预抽回采区域煤层瓦斯、穿层钻孔预抽石门揭煤区域煤层瓦斯、顺层钻孔预抽煤巷条带煤层瓦斯等方法成功治理煤与瓦斯突出的危害。  相似文献   

5.
通过对山东能源龙矿集团北皂煤矿海下软岩复杂地质条件下煤层瓦斯赋存状况、采掘工作面瓦斯涌出来源及涌出规律分析,提出了半封闭采空区埋管抽放、低位钻孔(上隅角插管)抽放,全封闭采空区抽放等多种抽放工艺相结合的综合抽放方法。方案实施以来工作面瓦斯抽放率达到60%-70%,从根源上消除了局部积聚的可能性,对三软地层综放回采工作面瓦斯治理工作具有指导意义。  相似文献   

6.
我国大部分矿区煤层属低透气性难抽煤层,给瓦斯治理和利用带来困难。为了提高煤层透气性或增加单位煤体钻孔长度,以达到提高抽放率的目的,本文对高瓦斯煤层瓦斯抽采进行研究,使煤矿开采效率提高。  相似文献   

7.
穿层钻孔抽采煤层瓦斯技术在一些矿井的应用实践证明,穿层钻孔抽采煤层瓦斯明显减少了煤巷掘进的瓦斯涌出量,降低煤与瓦斯突出强度,实现煤巷的安全快速掘进。如果有足够的抽采时间,会体现出更为显著的安全和经济效果。同时,还可以利用该工程提前抽采回采工作面区域内的煤体瓦斯,对于整个采区安全开采也有着重要的意义。  相似文献   

8.
本文以骆驼山煤矿的开采条件为背景,提出了更适用于该矿的瓦斯抽采设计方法即顺层斜向钻孔预抽法、定向长钻孔预抽法、高位钻孔抽采瓦斯、工作面采空区埋管抽采、老采空区抽采、掘进工作面瓦斯抽采,为类似矿井瓦斯抽采设计提供了参考。  相似文献   

9.
针对金河煤矿主采煤层瓦斯含量大、透气性差的特点,利用穿层钻孔实施高压水射流煤层割缝增透技术,实施后CH4平均抽放浓度增幅为30.57%,CO2平均抽放浓度增幅为23.85%,单孔瓦斯抽放流量平均提高104.02%,总抽放量增幅为3.79倍,效果非常明显。本技术为不具备保护层开采条件的地质构造复杂区域、保护不充分区域、石门揭煤等方面的消突工作提供了一定的借鉴。  相似文献   

10.
由于回采时工作面回风流中瓦斯浓度过大,瓦斯治理成本高。任楼煤矿根据自身实际情况,利用保护层开采提高煤层的透气性将大直径钻孔代替尾巷埋管抽放,进行多煤层瓦斯抽放提高工作面瓦斯抽放的效果。  相似文献   

11.
郑吉玉  王公忠 《爆破》2018,35(2):37-40,49
松动爆破是防治瓦斯突出的有效措施。针对煤层透气性差,突出危险预测指标高的问题,采用松动爆破技术对煤层进行卸压增透。结合某矿工作面煤体和爆破参数,理论计算了爆破后裂隙圈范围,主要包括应力波作用和静压破坏作用两部分,分别为0.41 m和1.47 m;通过布置钻孔并观测瓦斯流量变化,裂隙圈范围与理论计算较为接近,略小于应力波和静压破坏两部分理论计算之和;在理论计算和现场观测的基础上,确定合理的钻孔间距为3 m。采煤工作面经卸压爆破后,突出预测指标S(钻屑量)和q(瓦斯涌出初速度)分别下降了16.7%和57.1%,有效降低了工作面突出危险性。  相似文献   

12.
In underground coal extraction of fully mechanized caving, the overlying hard–thick sandstone main roof could control the failure extent and the movement evolution of the entire overburden strata. The instantaneous failure of the hard–thick sandstone main roof possibly causes strata pressure behaviors, rock-bursts and abnormal gas emissions, which may result in equipment damages and casualties. Tashan coalmine was chosen as a field case study base because of its super great mining height (SGMH) and the overlying hard–thick sandstone roof (HTSR). This mine has experienced a great deal of damaging hydraulic support and abnormal gas emission accidents caused by strata pressure behavior. The fracture failure analysis was analyzed based on “Key Strata Theory” and numerical simulation results. The hard–thick sandstone main roof could perform as a very large double-sided embedded rock beam in the primary fracture and as a cantilever-articulated rock beam in periodic fracture, simultaneously generates a huge hanging space in the gob. The fracture failure of the hard–thick sandstone main roof causes a permeability enhancement in the adjacent rock-coal strata and near face coal seam. The substantial amounts of gas stored in the remaining coal, surrounding rock strata and adjacent coal seams rush out and aggregate in the caved and fissure zone of the gob, thereby forming a huge gas cloud. The disasters due to coupled strata pressure behavior and abnormal gas emissions, which primarily occurred after primary and periodic fracture failure, are predominantly caused by the instantly fracture of main roof. When the main roof reached the ultimate broken span and underwent, rotation and collapse, substantial amounts of gas accumulating in the gob escaped to the working face under the extrusion and impaction of the caving rock strata, which easily produced abnormal gas emissions, some of which exceeded the statutory limit. Shortening the length of the HTSR failure span using hydraulic presplitting and decreasing the gas content of the coal seam using gas drainage technology are recognized as two effective approaches to solve this issue.  相似文献   

13.
在加工碳纤维增强树脂基复合材料(CFRP)时多用冷却工艺来提升加工质量。其中,空气冷却工艺因其方便性被广泛用于实际加工中。然而,目前尚缺少空气冷却方向对刀具磨损和加工质量的研究。文章通过控制冷却空气的方向,开展了干式切削、正向喷气和逆向吸气冷却条件下钻削CFRP材料的研究。获得了上述冷却条件对双顶角刀具第二主切削刃末端磨损的影响规律,发现气体冷却都能有效抑制刀具磨损,且在对出口温度影响相近的条件下,逆向冷却比正向冷却能够更好地抑制磨损。进而分析了冷却条件对钻削出口损伤的抑制效果,发现冷却、冷却方式对孔出口撕裂深度的抑制作用都较小,但逆向吸气冷却能够有效减小出口的毛刺高度,是一种有效提高制孔质量的冷却工艺。  相似文献   

14.
This paper aims to analyse and understand the origin and development of gas-dynamic phenomenon (GDP) that take place with certain regularity in underground coal mining. It provides a detailed analysis of how they are influenced by changes and increases in ground stresses (vertical and horizontal stresses) and variations in the pressure of methane gas contained in underground coal seams used for mining operations.Phenomenon of this nature have occurred in recent years in certain seams at the Sotón, Montsacro and San Nicolás pits in the central coal basin of Asturias (Spain). Describing and analysing them reveals the influence of the proximity of other operations at different levels of the same seam or located in different seams. Similarly, it indicates the influence of unmined zones and brusque changes in the thickness of the seam. The values of the concentration of gas at the coal face of the mined seam and its rate of desorption complement and justify all the previous explanations. The measurements taken were periodically obtained by means of boreholes in coal faces for coal seams mined using the sub-level method.  相似文献   

15.
针对煤矿开采中坚硬顶煤(板)冒落性差的问题,讨论了煤矿生产中由此产生的顶煤放出率、冲击 矿压、自燃发火和瓦斯积聚等技术难题;分析了坚硬顶煤(板)水力致裂弱化技术的岩体水力致裂裂缝扩展行 为规律、渗透压力对裂隙岩体宏细观结构的改造作用及其宏观力学响应,水压裂缝扩展形态控制技术,钻孔封 孔技术和岩体水力致裂弱化的监测监控的研究现状和技术发展趋势。  相似文献   

16.
针对大庆外围朝长地区未动用储量属于低渗透扶余油层,采用常规直井开发,单井产能低、开发效益差,为进一步提高低渗透扶余油层开发效果,通过水平井近平衡钻井、裸眼完井,减少了钻井及固井对储层污染,采用打孔管结合油膨胀封隔器工艺进行压裂改造,探索低产低渗透储层有效的开发途径。试油及投产效果表明,低渗透油藏采用近平衡钻井、裸眼完井能有效地保护储层,实施裸眼水平井储层压裂改造能够提高单井日产油,对进一步改善低渗透油藏开发效果有重要意义。  相似文献   

17.
The exploitation of shale gas has increasingly become the focus of worldwide energy industry. Due to the existence of natural/hydraulic fractures, most of the shale gas reservoirs exhibit high degree of heterogeneity and complexity which leads to the stress-dependent fracture conductivity of shale gas reservoir. Discrete fracture network (DFN) model is adopted in this research since the conventional continuum model cannot meet the numerical simulation requirements of fractured shale gas reservoir. A series of experiments about the fracture properties stress-dependent have been conducted on some shale core samples, the stress-dependent fracture conductivity correlation is selected and incorporated into the mathematical model to characterize the reduction of fracture conductivity potential with the reservoir pressure drop. The DFN model is applied to a shale gas reservoir with fracture network to study the effect of the stress-dependent fracture conductivity on the shale gas well performance. The results show that the effect of fracture conductivity reduction with pressure drop on the shale gas well performance depends on both the initial fracture conductivity and matrix permeability. The complex interactions between the fracture and matrix permeability should be considered when select the appropriate size of proppants for fracturing.  相似文献   

18.
A longitudinal vortex generator was introduced into spouted beds to improve the heat and mass transfer rates in a semi-dry desulfurization process. The flue gas desulfurization processes in a 3D conventional spouted bed (CSB) and a spouted bed with a longitudinal vortex (LVSB) were simulated and verified experimentally. The simulation results show that the generator can strengthen the gas-particle-slurry contact in the spouting and annular areas. The average interphase slip velocities of the gas-particle and gas–liquid in the LVSB were 26.6 and 26.5 % higher than that in the CSB. The generator also increased the liquid temperature and interphase mass transfer rates in the spouted beds. The simulated desulfurization efficiencies of the CSB and LVSB were 77.75 and 80.85 %, respectively, which indicate the addition of a generator is beneficial for promoting the semi-dry desulfurization process.  相似文献   

19.
[摘要]矿井事故高发区域是煤矿综采工作面,煤矿环境的特殊在很大程度上增加了确保安全生产的难度系数,矿井生产具有其他行业所不具有的特殊性、复杂性以及多变性,其中发生率较高的矿井事故类型有透水、煤炭自燃、瓦斯或煤尘爆炸以及职业病等。本文首先介绍了综采工作面常见事故类型,其次阐述了构建煤矿综采面安全生产评价指标体系应遵循的原则,最后对确定综采工作面安全生产评价指标权值加以探讨。  相似文献   

20.
煤矿深孔预裂爆破技术应用研究   总被引:2,自引:0,他引:2  
为解决较厚坚硬煤层的瓦斯突出和回采率低的问题,采用深孔预裂爆破的方法增加其透气性,并利用煤层松动产生的局部应力突变增加落煤量。根据爆破理论计算了爆破参数,确定了爆炸作用的裂隙范围。实践表明,煤层瓦斯含量降低,提高了回采率,试验与理论基本一致。  相似文献   

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