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41.
页岩-钢渣组合填料湿地强化脱氮除磷研究 总被引:10,自引:3,他引:7
以城市污水A/O工艺出水为处理对象,运用页岩和钢渣物化除磷、调控进水碳氮比和氮素氧化性等技术手段,在中试规模上研究了页岩和钢渣组合填料湿地的脱氮除磷效能及影响因素.结果表明,当COD面积负荷率、TN面积负荷率、TP面积负荷率、HRT(水力停留时间)分别为6.5~20.7 g·(m2·d)-1、2.57~8.22 g·(m2·d)-1、0.41~1.32 g·(m2·d)-1、0.5~1.6d时,①氨氮、亚硝态氮和硝态氮的去除率分别为85.8%、56.3%和18.6%,TN去除率为58.0%,TN面积负荷去除率为3.58g·(m2·d)-1,TN反应动力学常数为0.31 m·d-1,TN面积负荷去除率随进水TN负荷的增加而线性增加.②TP去除率为90.4%,TP面积负荷去除率为0.89 g·(m2·d)-1,TP反应动力学常数为0.86 m.d-1,TP面积负荷去除率随进水TP负荷的增加而线性增加.③水温、HRT、氮素组分、C/N等因素对湿地系统的脱氮除磷效率有显著影响.TN面积负荷去除率随HRT、COD/TN值的增加而幂函数增加.TN面积负荷去除率随水温(、NO2--N+NO3--N)/TN值的增加而呈指数函数增加. 相似文献
42.
Influence of Black Shales on Soils and Edible Plants in the Ankang Area, Shaanxi Province, P. R. of China 总被引:1,自引:0,他引:1
The Ankang black shales in P. R. of China provides an important example of natural geological materials containing toxic elements. This paper presents the results of environmental geochemical research on black shales, soils, waters and edible plants in the Ankang area, Shaanxi Province, P. R. of China. The study area lies in the northern margin of the Yangtze Platform; there are black shales which contains black shale, carbonaceous rocks and coal in the Cambrian Donghe Formation throughout the area. Mean trace element concentrations of the coal were high. Soils derived from these rocks tend to reflect their extreme geochemical composition. Chemical analysis of common plant species in the Ankang area showed a heterogeneous distribution of Se, Mo, and V within a single and among plant species. Selenium was more concentrated in radish than in legumes, and in potato more than in green vegetable. High V concentrations were found in two kinds of Chinese tea. Legume had more Mo in the seed than potato, although Mo concentrations in radish vary. Higher concentrations of Se and Mo are present in the leaf of radish. 相似文献
43.
通过实验研究了施用油母页岩废渣对大豆产量的影响,试验结果表明,施用油母页岩废渣能促进大豆生长发育,显著提高大豆产量,其中,中量油母页岩废渣21t/hm2·a配施氮磷钾化肥的效果最好,其增产率达184.03%,但随着油母页岩施用量的增加,其增产效果下降。 相似文献
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Growing energy demand has increased the need to manage conflicts between energy production and the environment. As an example, shale‐gas extraction requires substantial surface infrastructure, which fragments habitats, erodes soils, degrades freshwater systems, and displaces rare species. Strategic planning of shale‐gas infrastructure can reduce trade‐offs between economic and environmental objectives, but the specific nature of these trade‐offs is not known. We estimated the cost of avoiding impacts from land‐use change on forests, wetlands, rare species, and streams from shale‐energy development within leaseholds. We created software for optimally siting shale‐gas surface infrastructure to minimize its environmental impacts at reasonable construction cost. We visually assessed sites before infrastructure optimization to test whether such inspection could be used to predict whether impacts could be avoided at the site. On average, up to 38% of aggregate environmental impacts of infrastructure could be avoided for 20% greater development costs by spatially optimizing infrastructure. However, we found trade‐offs between environmental impacts and costs among sites. In visual inspections, we often distinguished between sites that could be developed to avoid impacts at relatively low cost (29%) and those that could not (20%). Reductions in a metric of aggregate environmental impact could be largely attributed to potential displacement of rare species, sedimentation, and forest fragmentation. Planners and regulators can estimate and use heterogeneous trade‐offs among development sites to create industry‐wide improvements in environmental performance and do so at reasonable costs by, for example, leveraging low‐cost avoidance of impacts at some sites to offset others. This could require substantial effort, but the results and software we provide can facilitate the process. 相似文献
46.
为了分析页岩的层理和水化损伤对钻井过程中井壁稳定性的影响,开展室内岩石三轴力学试验测试页岩原始状态和钻井液作用不同时间的力学特性;然后基于孔隙弹性理论和岩石弱面强度理论,综合考虑层理产状和水化损伤对页岩强度的影响,建立页岩地层井壁稳定性分析模型。结果表明:层理产状和水化损伤对井壁稳定性有显著的影响,都会导致坍塌压力升高,加剧井壁的不稳定性。综合考虑页岩的层理和水化损伤两个因素分析地层井壁稳定性,对优化不同时段钻井液性能,调整钻井液密度,保证钻井安全有重要意义。 相似文献
47.
中国页岩气资源开发利用的可行性评价 总被引:1,自引:0,他引:1
论文以可行性评价为切入点,从资源与赋存条件、综合开发利用条件、环境安全性及市场前景四方面因素选取了19 项指标,构建中国页岩气开发可行性评价指标体系,采用中、美对比研究方式,评价中国近期进行页岩气大规模开发利用的适宜性问题。研究表明:①市场需求、成本与价格、核心技术条件、含气量、水资源污染、水资源供应及政策支持等指标是影响页岩气开发的关键因素;②对比得分结果显示,中、美页岩气开发可行性等级分属中度偏下与中度偏上区间,得分差距较大;③中、美页岩气开发可行性值的差距,主要归因于两国在页岩气资源与赋存及综合开发利用条件方面的巨大差异。鉴于目前两国页岩气开发的实际情况,得分结果与现实具有较高符合度。 相似文献
48.
为深入研究页岩的水化特征及水化对井壁稳定的影响,以鄂尔多斯盆地石盒子组页岩为研究对象,开展了钻井液浸泡前后岩样的超声波透射实验、层理面直剪实验、三轴压缩实验,探讨了页岩水化的声学性质变化与岩石力学特征,分析了页岩水化对坍塌压力的影响。结果表明:弹性模量、泊松比等参数的变化难以准确评价页岩的水化特征,声波时差、衰减系数、时域曲线、频域曲线等超声波信号可作为研究页岩水化特征的有效手段;页岩水化直接导致其岩石力学性质发生变化,水化是坍塌压力上升的主要原因之一,对井壁稳定造成潜在的威胁;井壁稳定设计时应充分认识页岩的水化特征,避免井壁坍塌,确保钻井施工安全进行。 相似文献
49.
Stanley L. Ponce Richard H. Hawkins 《Journal of the American Water Resources Association》1978,14(5):1187-1200
ABSTRACT: This study emphasized a field investigation of salt release to overland flow from Mancos shale lands of the Price River Basin, Utah. Although a high degree of natural variation existed in the data, which precluded the separation of factors affecting diffuse salt loading that occurs during overland flow, a simplistic nonpoint source loading function developed on empirical concepts was fit to the data. This function was then used to calculate the average annual salt yield to the Price River by overland flow. It was found that even under severe conditions, the salt yields from Mancos shale lands due to overland flow is relatively minor, accounting for less than 1.5 percent of the average annual salt mass transported from the basin by the Price River. 相似文献
50.
William L. Jackson Randall P. Julander 《Journal of the American Water Resources Association》1982,18(6):995-1001
ABSTRACT: Relative yields of water, sediment, and salt (as indexed by electrical conductivity) were determined using simulated rainfall plots on three soil landform units on Mancos shale in the Price River Basin, Utah. Final infiltration rates on residual shale derived soils were between 0.13 and 0.50 cm/hr. No runoff was generated on cracked soils derived from aeolian deposits. Suspended sediment concentrations and elehcal conductivities were 180 and 68 times greater, respectively, for a steep dissected Mancos shale upland than for a low relief shale pediment and recent alluvial surface. Riling accounted for approximately 80 percent of the sediment produced on the steep, dissected shale surface. Channel scow and soil creep also produced measurable mounts of sediment. A survey of sediment basins in steep, dissected shale up lands indicated that an average of 1.25 Mg/ha/year of sediment is produced by that landform unit Carefully designed and located basin plugs can be used effectively to trap sediment, water, and salt from dissected shale uplands. 相似文献