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11.
目的为保障油田正常安全生产,促进油田含聚污水的循环利用。方法采用电絮凝技术单因素研究方法开展净化含聚污水的静态实验研究,探讨外加电流密度、极板间距、初始pH及聚合物浓度等因素对净化效果的影响规律。结果当初始pH为7.0,电流密度为4.0 m A/m2,极板间距为1.0 cm,电解16 min时,综合处理效果最佳。此时,含油量与浊度去除率分别为98.85%,99.93%,处理每克油平均消耗为0.0494 g的Al,处理每立方米含聚污水的能耗为0.2895 k Wh。污水中的聚合物浓度越小,净化效果越好。结论中性处理,极板间距为1.0 cm,外加电流密度为4.0 m A/m2,通电16 min是最佳处理条件。 相似文献
12.
运用CFD仿真软件Fluent,参考国内某炼厂常压塔挥发线管道结构和运行工况,对注水后管道内的多相多组分状态进行了模拟,编写了相应的传热传质模型,对其中的腐蚀性介质参数进行了计算分析,结果表明:在注入中性水后,挥发线管道内气相腐蚀性介质HCl和H_2S在水相中快速溶解,导致水相pH值呈酸性,注水点下游附近出现了液相跌落区,此处的pH值最低。对不同的注水流量和液滴粒径的注水工况进行模拟后,发现注水参数对跌落区的位置、最低pH值产生了影响,其中液滴粒径的影响更加显著。据此,预测了不同注水工艺对塔顶露点腐蚀状态的影响,以期指导腐蚀监测和工艺防腐。 相似文献
13.
对物质摩尔浓度表示方法及在环境监测分析中应用的讨论黄彩海,陈花果(陕西省环境监测中心站,西安710061)(西安公路学院环境工程研究所,西安710064)自摩尔和摩尔浓度法定为化学计量、计算的基本单位以后,一切论文、著作和正式出版物等,其有关化学物质... 相似文献
14.
Scenario Analysis for the San Pedro River, Analyzing Hydrological Consequences of a Future Environment 总被引:1,自引:0,他引:1
Kepner WG Semmens DJ Bassett SD Mouat DA Goodrich DC 《Environmental monitoring and assessment》2004,94(1-3):115-127
Studies of future management and policy options based on different assumptions provide a mechanism to examine possible outcomes and especially their likely benefits and consequences. The San Pedro River in Arizona and Sonora, Mexico is an area that has undergone rapid changes in land use and cover, and subsequently is facing keen environmental crises related to water resources. It is the location of a number of studies that have dealt with change analysis, watershed condition, and most recently, alternative futures analysis. The previous work has dealt primarily with resources of habitat, visual quality, and groundwater related to urban development patterns and preferences. In the present study, previously defined future scenarios, in the form of land-use/land-cover grids, were examined relative to their impact on surface-water conditions (e.g., surface runoff and sediment yield). These hydrological outputs were estimated for the baseline year of 2000 and predicted twenty years in the future as a demonstration of how new geographic information system-based hydrologic modeling tools can be used to evaluate the spatial impacts of urban growth patterns on surface-water hydrology. 相似文献
15.
Gu B Watson DB Wu L Phillips DH White DC Zhou J 《Environmental monitoring and assessment》2002,77(3):293-309
Zero-valent iron (Fe0)-based permeable reactive barriertreatment has been generating great interest for passivegroundwater remediation, yet few studies have paid particularattention to the microbial activity and characteristics withinand in the vicinity of the Fe0-barrier matrix. The presentstudy was undertaken to evaluate the microbial population andcommunity composition in the reducing zone of influence byFe0 corrosion in the barrier at the Oak Ridge Y-12 Plantsite. Both phospholipid fatty acids and DNA analyses were usedto determine the total microbial population and microbialfunctional groups, including sulfate-reducing bacteria,denitrifying bacteria, and methanogens, in groundwater andsoil/iron core samples. A diverse microbial community wasidentified in the strongly reducing Fe0 environment despitea relatively high pH condition within the Fe0 barrier (up topH 10). In comparison with those found in the backgroundsoil/groundwater samples, the enhanced microbial populationranged from 1 to 3 orders of magnitude and appeared to increase from upgradient of the barrier to downgradient soil. Inaddition, microbial community composition appeared to change overtime, and the bacterial types of microorganismsincreased consistently as the barrier aged. DNA analysisindicated the presence of sulfate-reducing and denitrifyingbacteria in the barrier and its surrounding soil. However, theactivity of methanogens was found to be relatively low,presumably as a result of the competition by sulfate/metal-reducing bacteria and denitrifying bacteria because of the unlimited availability of sulfate and nitrate in the site groundwater. Results of this study provide evidenceof a diverse microbial population within and in the vicinity ofthe iron barrier, although the important roles of microbial activity, either beneficially or detrimentally, on the longevityand enduring efficiency of the Fe0 barriers are yet to be evaluated. 相似文献
16.
改良亚甲基蓝比色法快速测定地表水中硫化物 总被引:1,自引:0,他引:1
探讨了亚甲基蓝比色法测定硫化物显色剂的用量和溶液的酸度,找出了最佳实验条件.实验得出:该方法的线性范围为0.0~0.6mg/L,最低检出限为0.004mg/L,RSD 0.5N~6.4%,回收率90%~98%。 相似文献
17.
The metal pollution in water and sediment of the River Hindon in western Uttar Pradesh (India) was assessed for Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn. The metal concentrations in water showed wide temporal variation compared with bed sediment because of variability in water discharge and variations in suspended solid loadings. Metal concentrations in bed sediments provided a better evaluation of the degree and the extent of contamination in the aquatic environment, Santagarh and Atali being the most polluted sites of the river. The ratio of heavy metals to conservative elements (Fe, Al, etc.) may reveal the geochemical imbalances due to the elevated metal concentrations normally attributed to anthropogenic sources. Metal/Al ratios for the bed sediments of the river Hindon were used to determine the relative mobility and general trend of relative mobility occurred Fe > Mn > Zn > Cr > Ni > Pb > Cu > Cd. 相似文献
18.
质量保证体系是网格实测法环境空气质量监测优化布点研究工作的重要组成 ,该体系可确保实测数据准确可靠和研究成果质量 ,具有可操作性并已在实践中应用 ,取得满意效果 相似文献
19.
20.
对GAM水环境预测模型提出了四点不同看法,与有关作者商榷,指出GM(1,1)模型与GAM模型二者并无优劣之差,精度亦相当。 相似文献