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1.
《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
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从资源紧缺、环境污染、产品低端等方面,总结了我国钒、钛、镍、钴、锂稀有金属资源在战略性新兴产业迅猛发展时代所面临的国家重大需求,回顾了领域近年来通过升级和变革传统稀有金属资源利用技术取得的主要进展和成就。其中煤基钠化冶炼、高温碳化?低温氯化、亚熔盐氧化等非常规介质强化手段是实现钒钛磁铁矿中钒、钛绿色高值高效利用的核心;盐酸常压浸出?低温选择性水解?共沉淀新技术是一种低成本、短流程高效高值利用红土镍矿全组分的先进技术代表;双功能协同复合萃取原理是实现高镁盐湖卤水的锂资源绿色利用的关键基础。基于固废资源化和源头减废两个思路,现阶段战略性金属资源的利用技术初步解决了环境污染和资源利用率低的问题,但仍存在资源绿色利用基础原理匮乏、产品科技含量低等普遍问题。以战略性产业关键材料为导向的绿色高值利用技术的应用基础研究是稀有金属相关绿色产业战略性发展的重要科技保障,是未来重要的前沿研究方向。 相似文献
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江汉盆地南部监利地区由于农田灌溉打水井,偶然发现井水抽出时伴有气体流出,点燃后能长时间燃烧。为此,对该地区的浅层气进行了采样分析。结果表明,浅层天然气气样CH4含量介于44.11%~51.57%之间,均值为47.03%,不含C2H6及其他重烃气体,干燥系数(C1/C1-5)为1,属典型干气。CH4碳同位素值介于-70.8‰ ~-71.0‰之间,均值为-70.9‰,CH4氢同位素值介于 -223‰~-226‰之间,均值为-224‰,CO2碳同位素值介于-12.6‰~-14.7‰之间,均值为-13.9‰,同位素特征表明研究区浅层气为氢气还原二氧化碳途径生成的生物气。通过与江浙-沿海平原、长江三角洲和洞庭盆地的第四系浅层生物气赋存特征进行对比,进一步明确了研究区内第四系生物气成藏特征,认为研究区第四系浅层生物气具有进一步勘察和研究的潜力。 相似文献
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超前管棚是浅埋暗挖施工保证安全的一项最重要的措施,对于含有大块石等障碍物的杂填土地层,管棚的施工难度极大。为解决这一难题,采用冲击钻进式超前旋喷管棚创这种新施工工艺,将管棚钢管加工成钻杆,与钻机动力头相连,通过干式冲击钻进,打穿过街道设计长度,然后安设一节带封闭堵头的钢管,继续逐节边向前输送钢管边旋喷注浆形成旋喷管棚,前端的钻具、短杆逐节卸除,直至带堵头的钢管接送至对面切口形成全长管棚为止,完成管棚施工,形成旋喷扩大注浆体这种效果更好的超前支护构件。该工艺施工速度快,安全经济,为该条件下浅埋暗挖的安全使用提供了有利保障。
超前管棚|冲击钻进|旋喷扩大|浅埋暗挖
Leading Pipe Shed Innovation of Shallow Undergrouud Excavation Backfill Layer 相似文献
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西藏区域地质构造发育,又属于高震区,在局部强降雨强降雪等恶劣小气候条件下,自然灾害频发,在高山深谷的江河上尤其容易发生堰塞湖。2018年10月17日凌晨5:00左右,西藏林芝加拉村下游约6km处(大峡谷核心区、无人区)雅鲁藏布江(以下简称“雅江”)左岸发生大规模泥石流,造成干流断流,形成影响很大的雅江加拉村堰塞湖。堰塞湖的治理一直是个世界难题,本文从2018年10月17日治理分析加拉堰塞湖的实践,阐述从水电开发角度,在灾害区上游建设高坝大库拦水调蓄,水库下游再采取截弯取直方式引走来水,作为防治雅江大峡谷河段今后可能出现大型堰塞湖重要治理手段,防止大型堰塞湖造成水淹城乡和溃堰水淹下游灾难的发生,从而达到既推进雅江水电开发,又较好治理了大峡谷河段自然灾害,实现把水电开发建成“功在当代,利在千秋”的减灾防灾工程。 相似文献
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Anaerobic methane oxidation and aerobic methane production in an east African great lake (Lake Kivu) 总被引:1,自引:0,他引:1
Fleur A.E. Roland Cédric Morana François Darchambeau Sean A. Crowe Bo Thamdrup Jean-Pierre Descy Alberto V. Borges 《Journal of Great Lakes research》2018,44(6):1183-1193
We investigated CH4 oxidation in the water column of Lake Kivu, a deep meromictic tropical lake with CH4-rich anoxic deep waters. Depth profiles of dissolved gases (CH4 and N2O) and a diversity of potential electron acceptors for anaerobic CH4 oxidation (NO3?, SO42?, Fe and Mn oxides) were determined during six field campaigns between June 2011 and August 2014. Denitrification measurements based on stable isotope labelling experiments were performed twice. In addition, we quantified aerobic and anaerobic CH4 oxidation, NO3? and SO42? consumption rates, with and without the presence of an inhibitor of SO42?-reducing bacteria activity. Aerobic CH4 production was also measured in parallel incubations with the addition of an inhibitor of aerobic CH4 oxidation. The maximum aerobic and anaerobic CH4 oxidation rates were estimated to be 27?±?2 and 16?±?8?μmol/L/d, respectively. We observed a difference in the relative importance of aerobic and anaerobic CH4 oxidation during the rainy and the dry season, with a greater role for aerobic oxidation during the dry season. Lower anaerobic CH4 oxidation rates were measured in presence of molybdate in half of the measurements, suggesting the occurrence of linkage between SO42? reduction and anaerobic CH4 oxidation. NO3? consumption and dissolved Mn production rates were never high enough to sustain the measured anaerobic CH4 oxidation, reinforcing the idea of a coupling between SO42? reduction and CH4 oxidation in the anoxic waters of Lake Kivu. Finally, significant rates (up to 0.37?μmol/L/d) of pelagic CH4 production were also measured in oxygenated waters. 相似文献
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Zoltán Vitál Nóra Boross István Czeglédi Bálint Preiszner Tibor Erős Kálmán Molnár Gábor Cech Csaba Székely Diána Sándor Péter Takács 《Journal of Great Lakes research》2021,47(1):236-241
In this study, we provide the first genetically verified distribution record beyond its native range of Ligula pavlovskii, a high-impact endoparasite of Ponto-Caspian gobies. According to parasitological surveys, ligulosis was detected for the first time in monkey goby individuals collected from Lake Balaton in 2004, 34 years after the first record of monkey goby in the lake. During a Lake Balaton survey in 2018, we detected tapeworms in 44.4% of the sampled monkey gobies. This prevalence is about two to ten times higher than it was reported from within the native range of the fish hosts. The same survey revealed an uneven spatial distribution of the ligulosis in the monkey gobies inhabiting different shoreline sections of the lake. We assume that the occurrence and recent distribution data of this high-impact endoparasite may provide useful information for potential biocontrol measures of invasive Ponto-Caspian gobies in the future. 相似文献
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沙河街组一段下亚段是歧口凹陷重要的页岩油发育层系,为进一步了解该段细粒沉积岩沉积环境、旋回特征和沉积模式,利用地震、测井、录井和系统取心分析资料对目的层位展开综合研究。研究区细粒沉积岩包括长英质页岩、碳酸盐质页岩(白云岩、灰质页岩、白云质页岩)、黏土质页岩和混合质页岩4种类型,混合质页岩、长英质页岩和碳酸盐质页岩占优势;总体为还原-强还原沉积环境,水体盐度较高,主要受陆源碎屑沉积和生物化学沉积作用控制;宽缓湖湾与歧口主凹之间形成高盐度带,受准同生期蒸发浓缩作用,滨-浅湖带高密度富Mg2+超咸水在重力作用下,沿着湖底向湖盆内部流动,早期形成的方解石发生白云石化,形成准同生白云岩;岩性组合受旋回控制作用明显,短期反-正旋回转换面之下位置发育一层稳定白云岩或白云质页岩,碳酸盐岩(甜点段)发育于长期旋回内的下降期半旋回,上升期长期旋回主要发育黏土质混合页岩和黏土质页岩(隔板层),进一步可以总结出强陆源碎屑供给区细粒沉积模式和弱陆源碎屑供给区细粒沉积模式。 相似文献