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101.
    
This paper presents a numerical simulation study that examines the CO2 injection‐induced salinity changes in groundwater formations. We use a simplified numerical model to simulate the migration of formation water caused by pressure build‐up during CO2 injection. A stacked reservoir consisting of a storage formation overlain by a geological seal and groundwater aquifer is modeled. We use a commercial reservoir simulator to run various realizations with different seal permeabilities, injection rates, lateral boundary conditions, and groundwater production rates. We then track salinity changes calculated by the simulations. We find that lateral boundary conditions and seal permeabilities are the most critical parameters that govern lateral and vertical displacement of formation water. If the seal permeability is high enough or the lateral boundary is closed, the vertical fluid displacement dominates the lateral displacement. Depending on seal thickness, injection rate and reservoir salinity, this has the potential to cause significant salinity change in the overlying groundwater aquifer. If the seal permeability is low or the lateral boundary is open, then the lateral displacement becomes dominant. If the storage formation extends to an up‐dip shallow groundwater formation, the higher the lateral fluid displacement the higher the increase in salinity of the groundwater. Moreover, salinity changes occur in the deeper part of the groundwater formation because displaced water is heavier than groundwater. This study shows that tracking salinity changes in numerical simulations may provide a quantitative measure of the change in groundwater quality. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd  相似文献   
102.
燃油交通工具是城市温室气体的重要来源之一,因此使用电动交通工具成为解决城市污染减排的重要措施.文章就正确认识电动交通工具污染减排的作用,蓄电池的生产管理、回收利用等进行了讨论,并提出了相应的对策和建议.  相似文献   
103.
    
Areal footprints of current and future hydraulically fractured oil and gas reservoirs and potential CO2 geological‐sequestration intervals often overlap in sedimentary basins. Significant vertical separations between prospective subsurface volumes, however, will limit their interaction, particularly if the carbon‐storage site is deeper than the hydrocarbon resource. Recent intense development of shale resources translates into a reduced need for sequestration capacity. It has also resulted in technological innovations directly transferable to the carbon‐storage industry, in particular progress on well completion, such as new approaches to cementing, more mature horizontal drilling methods, and development of field‐treatment techniques for saline water. In addition, knowledge collected by operators on stratigraphy and faults – for example, using 3D seismic – and on abandoned wells is directly useful in reducing risk in future carbon‐storage projects. Both industries can benefit from development of regional transmission pipelines, pipeline rights‐of‐way, and a trained workforce. From a regulatory standpoint, hydraulic fracturing of shale and tight formations is not considered injection. Under the US UIC program, because hydraulically fractured wells fall under the production category, they do not follow the same set of rules for protecting water resources as oil and gas industry disposal wells do (UIC Class II). Both subsurface uses share some risk elements, however. Environmental risks result mostly from abandoned wells and faults, poorly characterized for carbon storage, and from defective well completions and surface spills during oil and gas production. Operators of both fields are also concerned about disposal of large fluid volumes possibly generating seismic events. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd  相似文献   
104.
对油田井场的特定部位进行声强测定及频谱分析,发现其噪声强度均已超过国家标准。选健康,耳廊反射正常豚鼠30只,分别置于柴油机旁(8只),钻井平台(8只)和值班房(8只),余6只为正常对照。每天暴露6h,连续21d,记录豚鼠脑干电位及扫描电镜下形态学改变,结果表明,虽然钻井平台上的噪音强度低于柴油机组,但它对人耳的损伤程度却高于柴油机组。  相似文献   
105.
对目前项目选址环境可行性论证存在的问题进行了初步分析,并从政策规划的相符性、环境容量的允许性、敏感目标的影响性3个方面探讨了项目选址的环境可行性论证。  相似文献   
106.
分析了排污总量监测过程中关于实施总量监测排污口的规范化、优化设置总量监测点位、监测频次和采样方法、超标污染物判别等方面与污染源监督监测的区别以及存在的问题,并提出了相应的对策和措施。  相似文献   
107.
为评估磷酸铁锂(LFP)电池梯次应用的生命周期环境影响,设定直接应用和梯次应用2个应用场景,采用生命周期评价(LCA)方法,对应用场景生命周期各阶段的环境影响及其贡献进行分析.功能单位设定为应用总容量1GWh的LFP电池作为通讯基站(CBS)储能电池,循环寿命为800次.结果表明,2个应用场景的环境影响热点均为储能应用...  相似文献   
108.
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As a secondary pollutant of photochemical pollution, peroxyacetyl nitrate(PAN) has attracted a close attention. A four-month campaign was conducted at a rural site in North China Plain(NCP) including the measurement of PAN, O3, NOx, PM2.5, oxygenated volatile organic compounds(OVOCs), photolysis rate constants of NO2 and O3 and meteorological parameters to investigate the wintertime characterization of photochemistry from November 2018 to Fe...  相似文献   
109.
修复目标值的确定是污染地块环境监管的重要环节,通常基于风险评估方法计算风险控制值来确定.而对于砷污染地块,采用HJ 25.3-2019《建设用地土壤污染风险评估技术导则》推荐模型和参数推算得到的修复目标值往往低于土壤砷环境背景值,难以满足监管需求.系统梳理了国内外污染地块土壤砷修复目标值确定方法,探讨了基于土壤环境标准值、传统风险评估、层次化风险评估、等效风险评估及土壤砷环境背景值修正方法的实现路径与实践应用.结合我国污染地块监管策略和砷污染地块开发再利用现状,提出了基于土壤环境背景值、层次化风险评估和生物可给性相关参数修正的土壤砷修复目标值确定方法,旨在为我国砷污染地块的修复和再利用提供更加科学合理的方案.  相似文献   
110.
    
The competition between submersed plants has been recognized as an important factor influencing the structure of plant communitiesin shallow lakes. The ability of different species to take up and store nutrients from the surrounding ambience varies, and hence plantcommunity structure might be expected to affect the cycling of nutrients in lake ecosystems. In this study, the uptake of phosphorusby Hydrilla verticillata and Vallisneria natans was studied and compared in monoculture and competitive mixed-culture plantings.Results showed that for both studied species the phosphorus concentrations of different tissues and of whole plants was unaffected bycompetition. However, the quantity of phosphorus accumulated by whole plants of H. verticillata was significantly higher in mixtureculture than in monoculture, while that of V. natans was lower in the mixed culture. The results indicated that H. verticillata has acompetitive advantage over V. natans, when the two species are grown in competition, and is able to accumulate a greater quantity ofphosphorus.  相似文献   
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