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401.
Zhulu Lin Tong Lin Siew Hoon Lim Michael H. Hove William M. Schuh 《Journal of the American Water Resources Association》2018,54(1):225-239
The Bakken shale play in western North Dakota is one of the largest unconventional oilfields in the United States, but published research about impacts on the region's water resources is rare. In this study, besides examining North Dakota water management policies and activities, we also analyzed three datasets: the Bakken horizontal well completion data (2008‐2014), North Dakota permitted water consumption data (2000‐2014), and groundwater level and streamflow observations in western North Dakota (2000‐2014). We found from 2008 to 2014, the annual total industrial water uses for Bakken shale oil development ranged between 0.5 and 10% of statewide total consumptive water use. The percentage increases were between 3.0 and 40% within the Bakken oil production region. The increased population of temporary oilfield service workers contributed additional domestic water use, which was equivalent to ~15% of annual industrial water use for the shale oil development in the Bakken. Despite being in a semiarid region, the impact of Bakken development on regional water supply was limited because the water in the Bakken was adaptively managed and the region received on average over 20% more precipitation than normal during 2008‐2014. Of the 15 glaciofluvial aquifers under study, 12 have seen water levels increasing or unchanged and the water levels for the remaining 3 aquifers have decreased. 相似文献
402.
采用微电解—Fenton氧化—絮凝组合工艺处理油田压裂废水,优化了工艺条件。实验结果表明:最佳工艺条件为初始废水pH 3.0、铁屑加入量1.5 g/L(铁屑与活性炭的质量比1∶1)、微电解时间80 min、Fenton氧化时间120 min、H2O2加入量940 mg/L,阳离子聚丙烯酰胺加入量120 mg/L;在最佳工艺条件下处理废水后,COD由3 116.0 mg/L降至681.3 mg/L,总COD去除率达78.1%,3个工段的COD去除率依次为33.1%,37.9%,7.1%,出水水质满足现场回注标准(SY/T 5329—2012《碎屑岩油藏注水水质推荐指标及分析方法》);该组合工艺对废水的处理效果远优于单独微电解、Fenton氧化或絮凝工艺,且方法简单易行、药剂利用率高。 相似文献
403.
接种厌氧氨氧化(Anaerobic Ammonium Oxidation,ANAMMOX)颗粒污泥至上流式厌氧污泥床反应器(Up-flow Anaerobic Sludge Blanket,UASB),并控制进水NO_3~--N/NO_2~--N质量比为1∶1。在(33±1)℃下,通过研究不同进水总氮质量浓度(200 mg/L、400mg/L、600 mg/L)和水力停留时间(12 h、8 h、6 h、4 h)下的脱氮效能、污泥形态及微生物群落结构,多维分析上流式ANAMMOX反应器氮负荷提升过程中的运行性状。结果表明,在进水NO_3~--N和NO_2~--N质量浓度均为200 mg/L、总氮质量浓度为400 mg/L、水力停留时间为6h的运行工况下反应器可获得最佳处理效能,NO_3~--N、NO_2~--N和总氮去除负荷分别达到0.76 kg N/(m3·d)、0.75 kg N/(m3·d)和1.32kg N/(m3·d),三者去除率分别为95.0%、93.8%和82.5%。氮负荷提升过程中的污泥形态和微生物群落结构动态变化显示,相较于水力停留时间的缩短,进水总氮质量浓度增加对上流式ANAMMOX反应器运行过程的影响更为显著,其不仅导致了颗粒污泥解聚,还显著降低了微生物种群的多样性和均匀度。核酸测序结果表明,反应器中分布着3种潜在的ANAMMOX优势功能菌,且三者丰度会随进水总氮质量浓度增加而发生明显演替。研究表明,在上流式ANAMMOX反应器氮负荷提升过程中,进水总氮浓度的控制更为关键。 相似文献
404.
油气田压裂返排液处理技术探讨 总被引:2,自引:0,他引:2
水力压裂是中低渗油田、非常规页岩气田增产开采的重要措施,开采会产生大量的压裂返排液,处理难度大,可能导致比较严重的水污染问题.首先基于国内外油气田压裂返排液的典型水质指标,分析了油气田压裂返排液的水质特点,包括组成复杂、多数水质指标超过国内污水回用标准、油气田压裂返排液组成差异大且处理难点不同;从处理原理、优缺点、油气田应用条件及效果出发,探讨了可用于油气田压裂返排液处理的相关技术,并提出了中国油气田压裂返排液处理存在的问题与相应的建议. 相似文献
405.
为了解决居住在高层建筑中的人们遇险后安全疏散的问题,研究出一种新颖的无动力链梯逃逸系统。在没有电力资源的情况下,既要解决循环链梯缓降速度,实现平滑控制的问题,又要解决系统长期处于闲置状态,而不影响其可靠性的问题。提出了循环链梯缓降速度多组并联控制的方案;采用液压式并联控制机构,很好地解决了链梯缓降速度的平滑控制及其可靠性的问题;并成功地研制出循环链梯的试验装置,经实际的性能测试表明,具有启动负荷小、运行平稳、工作可靠的特点。 相似文献
406.
Creighton R. Omer E. James Nelson Alan K. Zundel 《Journal of the American Water Resources Association》2003,39(2):467-475
ABSTRACT: Current data collection technologies such as light detection and ranging (LIDAR) produce dense digital terrain data that result in more accurate digital terrain models (DTMs) for engineering applications. However, such data are redundant and often cumbersome for hydrologic and hydraulic modeling purposes. Data filtering provides a means of eliminating redundant points and facilitates model preparation. This paper demonstrates the impact of varied data resolution on a case study completed for a 2.3 mi2 area with mild slopes (about 001 ft/ft) along Leith Creek near Laurinburg, North Carolina. For the original data set and seven filtered data sets, filtering induced changes in elevation, area, and hydraulic radius were determined for 10 water depths at 23 cross sections. Water surface elevations resulting from HEC‐RAS (Hydrologic Engineering Center‐River Analysis System) models for each data set were then compared. A hydraulic model sensitivity analysis was also conducted to compare filtering error to error introduced by variation in flow rates and roughness values. Finally, automated floodplain delineation was performed for each filter level based on the computed hydraulic model results and the filtered LIDAR elevations. Data filtering results indicate that significant time savings are achieved throughout the modeling process and that filtering to four degrees can be performed without compromising cross‐sectional geometry, hydraulic model results, or floodplain delineation results. 相似文献
407.
William V. Sweet Jens W. Geratz 《Journal of the American Water Resources Association》2003,39(4):861-871
ABSTRACT: Bank full hydraulic geometry relationships relate stream channel geometry to watershed size for specific physiographic regions. This paper presents bank full hydraulic geometry relationships and recurrence intervals for the Southeastern Plain coercion and the flat woods subtype of the Middle Atlantic Coastal Plain ecoregion found within North Carolina's Coastal Plain physiographic province. Cross‐sectional and longitudinal survey data from gated and unpaged streams were used to compute channel dimension and profile information. Power functions were developed, relating drainage area to bank full discharge, cross‐sectional area, width, and mean depth. Recurrence intervals of bank full events were estimated from gagged streams using both a Log‐Pearson Type III distribution of peak annual discharge and a partial‐duration series of average daily discharge. Results from both methods indicate that average bank full recurrence intervals for the study area are below one year. Determinations of recurrence intervals by the Log‐Pearson Type III distribution were for the most part inconclusive (less than one year), while a partial duration series estimated a 0.19 year average, ranging from 0.11 to 0.31 years. 相似文献
408.
409.
树皮填料补充碳源人工湿地脱氮初步试验研究 总被引:9,自引:3,他引:6
人工湿地可应用于城市污水厂出水深度处理和农业污染治理,但反硝化碳源不足问题制约了其脱氮能力.本试验利用树皮作为垂直流人工湿地强化反硝化脱氮填料,分析了水力负荷、硝酸盐负荷以及pH对人工湿地脱氮效果的影响.结果表明,人工湿地可以达到预期的反硝化水平,反硝化速率随水力负荷、硝酸盐负荷的增加而增大,去除率随两者的增加而减小,... 相似文献
410.