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1.
《International Journal of Hydrogen Energy》2021,46(69):34356-34361
This study investigates the ability of hydrogen (H2) to wet clay surfaces in the presence of brine, with implications for underground hydrogen storage in clay-containing reservoirs. Rather than measuring contact angles directly with hydrogen gas, a suite of other gases (carbon dioxide (CO2), argon (Ar), nitrogen (N2), and helium (He)) were employed in the gas-brine-clay system under storage conditions (moderate temperature (333 K) and high pressures (5, 10, 15, and 20 MPa)), characteristic of a subsurface environment with a shallow geothermal gradient. By virtue of analogies to H2 and empirical correlations, wettabilities of hydrogen on three clay surfaces were mathematically derived and interpreted. The three clays were kaolinite, illite, and montmorillonite and represent 1:1, 2:1 non-expansive, and 2:1 expansive clay groups, respectively. All clays showed water-wetting behaviour with contact angles below 40° under all experimental set-ups. It follows that the presence of clays in the reservoir (or caprock) is conducive to capillary and/or residual trapping of the gas. Another positive inference is that any tested gas, particularly nitrogen, is suitable as cushion gas to maintain formation pressure during hydrogen storage because they all turned out to be more gas-wetting than hydrogen on the clay surfaces; this allows easier displacement and/or retrieval of hydrogen during injection/production. One downside of the predominant water wettability of the clays is the upstaged role of biogeochemical reactions at the wetted brine-clay/silicate interface and their potential to affect porosity and permeability. Water-wetting decreased from kaolinite as most water-wetting clay over illite to montmorillonite as most hydrogen-wetting clay. Their wetting behaviour is consistent with molecular dynamic modelling that establishes that the accessible basal plane of kaolinite's octahedral sheet is highly hydrophilic and enables strong hydrogen bonds whereas the same octahedral sheet in illite and montmorillonite is not accessible to the brine, rendering these clays less water-wetting. 相似文献
2.
《矿业科学技术学报(英文版)》2020,30(2):265-269
The purpose of this study was to develop a physico-mathematical model and technique for estimation of chemical bond stability depending on electric field intensity of an external point charge. A hypothesis for a possible physico-chemical mechanism of the formation of additional harmful gases in the rock destruction by blasting was proposed. The theoretical basis of the hypothesis is the method of theretical evaluation of bond energy depending on the distance to a point charge, the third Coulomb centre. The quantum-mechanical model for calculating the electronic terms of molecules makes it possible to solve problems associated with the determination of parameters of molecules under the action of various physical fields on the system under consideration. The model was approved for some diatomic molecules. The discrepancy between the experimental data and calculated data did not exceed 14%, which proves accuracy of the obtained results. The model can be used in the field of research into the causes of gas-dynamic phenomena in underground coal mines, in studies of the degree of stability of nanostructured components of coal under physical influences, and in the theoretical design of new compounds and structures in the field of nanomaterial science and nanotechnology. 相似文献
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结合东同矿业公司井下原地溶浸的试验研究情况,分析了细菌浸出-萃取-电积工艺过程中存在的问题并提出了解决方法,探讨了该工艺应用研究的发展方向与前景。 相似文献
5.
Leonhard E. Bernold 《Canadian Metallurgical Quarterly》2003,129(6):645-652
The need for better protecting our vital infrastructure from being damaged or destroyed has received increased attention since the terrorist attacks on September 11, 2001. The tragedy of having thousands of innocent people die before the eyes of an entire nation awakened people to the reality of “managed” attacks of unthinkable magnitudes. However, tragedies of a smaller scale are a daily occurrence but accepted as “collateral damage” of work in an unsafe environment. This paper presents a cost-benefit analysis to address the question of how much money should be spent in protecting underground utilities from damage. During the study of an actual incident it was found that the total costs of such accidents are vastly underreported because only costs for emergency responses and repair are tallied up. This paper makes the case that a comprehensive approach for assessing the total economic impact of such incidents on the public, business, and government is the critical stepping stone to a mathematical optimization of expenditure for damage prevention. In addition, the reader will quickly realize that the use of the presented optimization model provides theoretical underpinning for the engineering profession in its effort to better protect our critical infrastructure from terrorist attacks. 相似文献
6.
岩壁梁是一种新型结构,为通过一定深度的锚杆将钢筋混凝土梁固定在地下厂房两侧的岩壁上,而吊车荷载则通过锚杆和钢筋混凝土与岩石接触面的摩擦力传到岩体上,形成岩壁梁和岩体共同受力的结构。岩壁梁是地下厂房施工和运行的核心建筑物,岩壁梁锚杆和混凝土的施工质量是直接关系到岩壁梁成败的关键,所以施工技术和施工质量均要求极高,是地下厂房系统施工的重点和难点。本文介绍了瀑布沟水电站地下厂房岩壁梁锚杆和混凝土施工的关键技术及质量控制经验,可供同类工程借鉴参考。 相似文献
7.
国际承包商在二滩工程中的许多施工布置和方法,施工技术和工艺、施工设备和措施很具有特色,扩展了我们的视野、丰富的我们的思路。总结其经验,可作为国内类似工程的参考。 相似文献
8.
本文简要地介绍了我国几个地下矿在锚喷网联合支护的硐室工程中堵漏防渗处理所取得的良好效果,可供类似矿山参考。 相似文献
9.
理论推导证明了静水压力模式与动水压力模式下地下水作用效果的差异,并且结合前人的研究成果,提出要取得合理的稳定性计算结果,两种水压力模式下所选用的强度参数应有所区分,对于静水压力模式,应取快剪或不排水剪指标;对于动水压力模式,则应取用慢剪或排水剪指标。最后采用一个具体的工程实例验证了结论的合理性。 相似文献
10.
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我国的西气东输工程从新疆塔里木油田到上海,管线长度达4000公里,为确保对长江三角洲地区安全稳定的供气,就必须在长江三角洲地区建设地下储气库,从而保证在管线故障期间应急供气,同时利用地下储气库调节冬季和夏季用气量的差异,保证长输管线的高效、平稳运行。在长江三角洲地区经地库址选择,目前准备将常州盆地的金坛盐矿用以建设地下储气库。盐穴地下储气库主要选择在盐层或盐兵上,利用水溶方式形成地下溶腔进行储气,选择合适的建库地址要结合地质、水、工程等诸多因素,造腔过程中需要采取一系列控制技术,在造腔过程中还要及时采取声纳测井技术进行跟踪监测,造腔过程的检测及腔体完成后的密封安全性检测是气库能否投入运行的关键。 相似文献