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排序方式： 共有623条查询结果，搜索用时 15 毫秒
1.
为了探究气井泄漏气体对环空带压的影响,根据气井环空内气体运移特点,综合考虑气泡在环空运移过程中受浮力、重力、黏性阻力、附加质量力和Basset力,建立持续环空带压井的气泡瞬态运移预测模型;基于相似原理设计环空气体瞬态运移试验装置,开展试验,探究不同注气量下气体瞬态运移特性,并验证气泡瞬态运移模型的可靠性;针对典型气井油套持续环空带压过程,开展敏感性分析。结果表明:气泡直径、泄漏点压力、温度与液体密度是影响气泡运移速度的主要因素;气泡运移速度越快,持续环空带压恢复的时间越短,气井环空压力无法及时卸载,导致井筒安全性降低。 相似文献
2.
Brian Ellis Catherine Peters Jeffrey Fitts Grant Bromhal Dustin McIntyre Robert Warzinski Eilis Rosenbaum 《Greenhouse Gases: Science and Technology》2011,1(3):248-260
A flow‐through experiment was performed to investigate evolution of a fractured carbonate caprock during flow of CO2‐acidified brine. A core was taken from the Amherstburg limestone, a caprock formation overlying the Bois Blanc and Bass Islands formations, which have been used to demonstrate CO2 storage in the Michigan basin. The inlet brine was representative of deep saline brines saturated with CO2, resulting in a starting pH of 4.4. Experimental conditions were 27 °C and 10 MPa. X‐ray computed tomography and scanning electron microscopy were used to observe evolution of fracture geometry and to investigate mineralogical changes along the fracture surface. The initial brine flow corresponded to an average fluid velocity of 110 cm hr−1. After one week, substantial mineral dissolution caused the average cross‐sectional area of the fracture to increase from 0.09 cm2 to 0.24 cm2. This demonstrates that carbonate caprocks, if fractured, can erode quickly and may jeopardize sealing integrity when hydrodynamic conditions promote flow of CO2‐acidified brine. However, changes to fracture permeability due to mineral dissolution may be offset by unaltered constrictions along the flow path and by increases in surface roughness. In this experiment, preferential dissolution of calcite over dolomite led to uneven erosion of the fracture surface and an increase in roughness. In areas with clay minerals, calcite dissolution left behind a silicate mineral‐rich microporous coating along the fracture wall. Thus, the evolution of fracture permeability will depend in a complex way on the carbonate content, as well as the heterogeneity of the minerals and their spatial patterning. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献
3.
试论煤矿井下快速断电安全技术 总被引：3，自引：4，他引：3
论述了煤矿井下漏电保护和短路保护装置的现状和实施快速断电安全技术的必要性;介绍了煤矿快速断电安全技术的发展水平;对快速断电安全技术中的几个问题进行了探讨;提出了可行的缩短故障取样时间技术方案 相似文献
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Rebecca L. Lewison Andrew F. Johnson Jianbang Gan Robin Pelc Katie Westfall Mark Helvey 《Conservation Letters》2019,12(3):e12628
Natural resource policies enacted to protect environmental integrity play an important role in promoting sustainability. However, when resources are shared ecologically, economically, or through a common, global interest, policies implemented to protect resource sustainability in one domain can displace, and in some cases magnify, environmental degradation to other domains. Although such displacement has been recognized as a fundamental challenge to environmental and conservation policy within some resource sectors, there has been little cross-disciplinary and cross-sectoral integration to address the problem. This suggests that siloed knowledge may be impeding widespread recognition of the ubiquity of displacement and the need for mitigation. Here, we connect research across multiple disciplines to promote a broader discussion and recognition of the processes and pathways that can lead to displaced impacts that countermand or undermine resource policy and outline a number of approaches that can mitigate displacement. 相似文献
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Shinya Inazumi Hiroyasu Ohtsu Yu Otake Makoto Kimura Masashi Kamon 《Journal of Material Cycles and Waste Management》2009,11(1):55-64
An evaluation method that can express the local leakage of leachate from joint sections in steel pipe sheet pile (SPSP) cutoff
walls is discussed in this study. In particular, the evaluation of environmental feasibility (containment of leachates containing
toxic substances) considering a three-dimensional arrangement and hydraulic conductivity distribution of the joint sections
in the SPSP cutoff wall is compared with an evaluation that uses the equivalent hydraulic conductivity. This equivalent hydraulic
conductivity assumes that the joint section and the steel pipe are integrated; therefore, the hydraulic conductivity is substituted
with a uniform permeable layer. However, in an evaluation that employs the equivalent hydraulic conductivity, it is difficult
to consider the local leakage of leachate containing toxic substances from the joint sections in the SPSP cutoff wall. It
was established that evaluations of the environmental feasibility of SPSP cutoff walls with joint sections must take into
account the local leakage of leachates containing toxic substances from the joint sections. Also, it was clarified that technologies
that lower the hydraulic conductivities of joint sections in SPSP cutoff walls and also facilitate the use of sparser joint
arrangements contribute significantly to increasing the environmental feasibility of SPSP cutoff walls at landfill sites. 相似文献
10.
提出了埕岛油田海底管道内缺陷漏磁检测需解决的主要问题,研发了(0)325 mm管道内缺陷漏磁检测装置,确定了海底管道漏磁检测工艺流程,配套了管道检测发射装置、接受装置等相关设施,实现了海底管道的漏磁检测、缺陷分析和安全评估. 相似文献