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101.
针对某矿1102工作面近距离顶板灰岩含水层是否具有突水危险性,采用瞬变电磁探测和UDEC数值模拟的方法,就顶板灰岩富水性分区及覆岩结构稳定性、导水裂隙发育特征进行了深入研究。研究结果表明:1顶板灰岩含水层有2处含水较强区,1处含水中等区,2处含水中等偏弱区。21煤上覆岩层裂隙发育集中在采空区后方、前方煤壁处及工作面中部离层区。裂隙发育高度随采空区跨度增加而增大,两者呈非线性关系。开挖40~120 m时,裂隙发育高度突增;开挖70 m、裂隙高度为22 m时发展至灰岩含水层。315 m厚砂岩充当了隔水层,工作面突水危险性较小。4采用新型化学注浆堵水材料——改性脲醛树脂,成功进行了工作面防治水试验,效果显著。 相似文献
102.
考虑到潜水含水层普遍存在入渗补给这一客观事实,本文应用迭加原理推导、建立有均匀入渗条件下潜水稳定井流公式. 相似文献
103.
山西运城盐湖资源的保护与可持续利用 总被引:2,自引:0,他引:2
简述了山西运城盐湖的形成与发展,分析了盐湖目前面临的生态环境问题,提出了保护、治理盐湖以实现可持续发展的措施。 相似文献
104.
《International Journal of Hydrogen Energy》2021,46(70):34822-34829
The challenge associated with large-scale hydrogen storage is a pertinent one to achieve a hydrogen economy. The increasing global demand for clean and green energy is the driving force to propel such an economy. Furthermore, hydrogen is also considered an alternative energy source compared to fossil fuel as a clean energy alternative. Hydrogen geo-storage in a deep saline aquifer, depleted oil and gas reservoirs can resolve this challenge. We assess the potential of a saline aquifer in a sandstone formation to store hydrogen through first-of-its-kind x-ray micro-computed tomography miniature coreflood experiments. The investigation shows that ~65% of the sandstone's pore volume can be occupied by hydrogen when injected at a slow rate. Residual saturation of hydrogen upon brine injection can be ~41%. 相似文献
105.
山西焦煤霍州煤电集团干河煤矿2092巷掘进期间受上覆k8砂岩含水层影响,巷道顶板出现淋水现象,不但降低了巷道掘进效率,而且软化了顶板岩体,降低了顶板支护质量,甚至会引发顶板水害事故。为了2092巷掘进安全,避免水害事故发生,决定对2092巷采取合理有效的探放水设计及安全技术措施。分析了2092巷掘进期间的上覆含水层探放水施工设计,并总结了采取的安全技术措施。从实际应用效果来看,采取探放水施工后2092巷掘进期间共计探放上覆含水层积水量达2447 m3,取得了显著应用成效。 相似文献
106.
《International Journal of Hydrogen Energy》2022,47(53):22482-22494
Hydrogen is among a few promising energy carriers of the future mainly due to its zero-emission combustion nature. It also plays an important role in the transition from fossil fuel to renewable. Hydrogen technology is relatively immature and serious knowledge gaps do exist in its production, transport, storage, and utilization. Although the economical generation of hydrogen to the scale required for such transition is still the biggest technical and environmental challenge, unlocking the large-scale but safe storage is similarly important. It is difficult to store hydrogen in solid and liquid states and storing it in the gaseous phase requires a huge volume which is just available in subsurface porous media. Sandstone is the most abundant and favourable medium for such storage as carbonate rock might not be suitable due to potential geochemical reactions.It is well established in the literature that interaction of the host rock-fluid and injected gas plays a crucial role in fluid flow, residual trapping, withdrawal, and more generally storing capacity. Such data for the hydrogen system is extremely rare and are generally limited to contact angle measurements, while being not representative of the reality of rock-brine-hydrogen interaction(s). Therefore, we have conducted, for the first time, a series of core flooding experiments using Nuclear Magnetic Resonance (NMR) to monitor hydrogen (H2) and Nitrogen (N2) gas saturations during the drainage and imbibition stages under pressure and temperature that represent shallow reservoirs. To avoid any geochemical reaction during the test, we selected a clean sandstone core plug of 99.8% quartz (Fontainebleau with a gas porosity of 9.7% and a permeability of 190 mD).Results show significantly low initial and residual H2 saturations in comparison with N2, regardless of whether the injection flow rate or capillary number were the same or not. For instance, when the same injection flow rate was used, H2 saturation during primary drainage was 4% and it was <2% after imbibition. On other hand, N2 saturation during the primary drainage was 26% and it was 17% after imbibition. However, when the same capillary number of H2 was utilised for the N2 experiment, the N2 saturation values were ~15% for initial gas saturation and 8% for residual gas saturation. Our results promisingly support the idea of hydrogen underground storage; however, we should emphasise that more sandstone rocks of different clay mineralogy should be investigated before reaching a conclusive outcome. 相似文献
107.
针对厚黄土覆盖区煤矿开采破坏地下水的问题,以山西省屯留县常村煤矿为例,采用GMS软件对研究区地下水流进行模拟及识别检验,通过改变松散含水层渗透系数及水头的大小,定量研究冒落裂隙带未沟通松散含水层下伏弱透水层底板、弱透水层性质不变条件下,厚黄土覆盖区煤矿开采对不同水力条件松散含水层的影响。结果表明,S6采区开采结束后,在采区附近出现降落漏斗,漏斗影响面积及中心处水位降深随时间的增加而加大,增大速率由大到小;不同渗透系数条件下,预测前期渗透系数越大,降深越大,影响面积越大,预测后期渗透系数越大,降深越小,影响面积越大;不同水头条件下,在整个预测期内水头越大,降深及影响面积均越大。 相似文献
108.
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110.
第Ⅲ承压含水层作为江苏沿海地区的主开采层,超采问题普遍存在,已形成若干区域性地下水位降落漏斗,甚至引发淡水咸化、地面沉降等环境地质问题。为保证当地经济的可持续发展,在充分了解研究区水文地质条件的基础上,利用区域第Ⅲ承压含水层观测孔的多年水位监测资料,重点分析江苏沿海地区第Ⅲ承压含水层开发利用的2个阶段(超采阶段、控制开采和压缩开采阶段)地下水动力场的演变,从各水文地质区间界线的迁移、区域性降落漏斗及地下水水位动态等方面系统阐述了水动力场时空演化的6个发展过程(1990、1995、2000、2005、2010、2015年),发现主采层地下水动力场对开采活动的响应机制十分积极,地下水位对限采的响应机制多为滞后响应,滞后时间与水文地质参数、距漏斗中心距离有关。 相似文献