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51.
52.
本文利用室内电阻率测试的方法研究了研究了饱和土和不饱和土两类土中含油污水的侵入量对其导电性的影响.测试结果表明,对于不饱和土,含油污水的侵入会改变土的饱和度从而引起其电阻率的降低,侵入量越大其电阻率越低;而饱和土的电阻率随含油污水侵入量的增大而增大直到趋于稳定.基于此,通过室内模拟土层污染和野外实地观测污染土层的方式研究了含油污水污染不同饱和度土层的电剖面异常特征,在不饱和土层中污染区域表现为相对低阻异常区而在饱和土层中表现为相对高阻异常区.通过对比不同时期的监测结果显示异常区的范围随污染区的变化而变化,并可反映出污染区的实际分布.文章分析了利用电阻率法进行含油污水污染地下介质调查的几个模糊点,对提高探测效果具有指导意义. 相似文献
53.
Penelope A. Luckens 《新西兰海洋与淡水研究杂志》2013,47(3):355-378
Experiments using cages at four shore levels were carried out to determine the part played by the feeding of the gastropods Neothais scalaris and Lepsiella scobina on the zonation of three species of intertidal barnacles: Chamaesipho brunnea, C. columna, and Epopella plicata. The lower limit of the two larger barnacle species was determined by predation, but C. columna was affected only in the absence of the other two barnacles. 相似文献
54.
《城镇污水处理厂污泥处理处置技术规范》[1]执行前,市政污泥往往直接倾倒于填埋场形成污泥库,导致垃圾设计库容显著降低。为恢复填埋场库容,许多填埋场面临污泥库的原位加固处理。通过2组模型试验,探讨真空预压处理污泥的可行性。试验结果表明,真空预压后污泥含水率显著降低,强度提高至2~4 kPa;污泥排水固结系数随预压过程发展表现出非线性;排水板周围污泥含水率和渗透系数降低明显,阻碍离排水板较远处污泥排水固结,因此减少排水板间距可显著提高污泥处理效果;真空预压过程中污泥中孔压变化规律与常规淤泥质土有明显区别,特别是远离排水板的位置孔压消散幅度小,表明污泥中孔压消散规律不符合传统的太沙基固结理论;污泥真空预压过程中,间歇式通正气压会在处理初期阶段加快排水速率,但整体改善作用不明显;真空预压可作为污泥减量化的一种途径,如要满足后续堆载垃圾的要求,还需配合其他原位处理方法进一步提高强度。 相似文献
55.
High‐frequency water quality monitoring in an urban catchment: hydrochemical dynamics,primary production and implications for the Water Framework Directive 下载免费PDF全文
Sarah J. Halliday Richard A. Skeffington Andrew J. Wade Michael J. Bowes Emma Gozzard Jonathan R. Newman Matthew Loewenthal Elizabeth J. Palmer‐Felgate Helen P. Jarvie 《水文研究》2015,29(15):3388-3407
This paper describes the hydrochemistry of a lowland, urbanised river‐system, The Cut in England, using in situ sub‐daily sampling. The Cut receives effluent discharges from four major sewage treatment works serving around 190 000 people. These discharges consist largely of treated water, originally abstracted from the River Thames and returned via the water supply network, substantially increasing the natural flow. The hourly water quality data were supplemented by weekly manual sampling with laboratory analysis to check the hourly data and measure further determinands. Mean phosphorus and nitrate concentrations were very high, breaching standards set by EU legislation. Although 56% of the catchment area is agricultural, the hydrochemical dynamics were significantly impacted by effluent discharges which accounted for approximately 50% of the annual P catchment input loads and, on average, 59% of river flow at the monitoring point. Diurnal dissolved oxygen data demonstrated high in‐stream productivity. From a comparison of high frequency and conventional monitoring data, it is inferred that much of the primary production was dominated by benthic algae, largely diatoms. Despite the high productivity and nutrient concentrations, the river water did not become anoxic, and major phytoplankton blooms were not observed. The strong diurnal and annual variation observed showed that assessments of water quality made under the Water Framework Directive (WFD) are sensitive to the time and season of sampling. It is recommended that specific sampling time windows be specified for each determinand, and that WFD targets should be applied in combination to help identify periods of greatest ecological risk. © 2015 The Authors. Hydrological Processes published by John Wiley & Sons Ltd. 相似文献
56.
Gil Penha-Lopes Erik Kristensen Perrine Mangion José Paula 《Marine pollution bulletin》2010,60(4):560-572
Benthic metabolism (measured as CO2 production) and carbon oxidation pathways were evaluated in 4 mangrove mesocosms subjected daily to seawater or 60% sewage in the absence or presence of mangrove trees and biogenic structures (pneumatophores and crab burrows). Total CO2 emission from darkened sediments devoid of biogenic structures at pristine conditions was comparable during inundation (immersion) and air exposure (emersion), although increased 2-7 times in sewage contaminated mesocosms. Biogenic structures increased low tide carbon gas emissions at contaminated (30%) and particularly pristine conditions (60%). When sewage was loaded into the mesocosms under unvegetated and planted conditions, iron reduction was substituted by sulfate reduction and contribution of aerobic respiration to total metabolism remained above 50%. Our results clearly show impacts of sewage on the partitioning of electron acceptors in mangrove sediment and confirm the importance of biogenic structures for biogeochemical functioning but also on greenhouse gases emission. 相似文献
57.
组合生物技术处理制药废水及其生物相 总被引:2,自引:0,他引:2
为有效治理化学制药废水和生物制药废水,采用水解酸化-活性污泥[-曝气生物滤池组合工艺对制药废水进行室内模拟生物处理研究。结果表明:该工艺对出水COD、BOD5的去除率均大于90%,已达到《污水综合排放标准》(GB 8978-1996)二级标准。对生物相的显微镜观察分析表明,污泥絮体和生物膜生长良好,并出现变形虫、轮虫和漫游虫等原生和后生动物。对各构筑物中的细菌进行分离纯化,同时应用BIOLOG细菌鉴定系统进行鉴定,分别得到8株、3株、6株可培养的细菌。 相似文献
58.
The effect of a reactive azo dye (the hydrolyzed form of Reactive Orange 107, HRO107) on the digestion of municipal waste sludge (WS) was studied. The study also focused on the effect of acclimation of the anaerobic mixed culture on dye treatment. Anaerobic batch assays were carried out in serum bottles under mesophilic conditions. Unacclimated and acclimated anaerobic mixed cultures were used for the study. Both unacclimated and acclimated anaerobic cultures completely reduced HRO107 during WS digestion. Inhibitory HRO107 concentration was found to be 800 mg/L for unacclimated mixed culture. Acclimation increased the inhibitory concentration level from 800 to 3200 mg/L. Sulfanilic acid and four other unidentified dye reduction end products were detected at the end of the assays. The results of this study indicated that anaerobic municipal WS digesters have the potential to be a cost efficient and effective pre treatment method. 相似文献
59.
论述在城镇雨污分流工程中采用非开挖技术需要工程勘察的内容和要求。针对非开挖技术特点,与常规市政工程勘察的对比分析,得出采用非开挖技术施工所需要的工程勘察特性。结合廊坊市雨污分流非开挖试验段工程,分析了前期工程勘察对后期非开挖工程施工的影响,具体分析工程地质勘察和施工区域地下管线探测特殊性对非开挖工程设计、施工的意义。最后从雨污分流非开挖试验段工程结论出发,总结采用非开挖技术施工进行工程勘察的常规性内容,为以后类似工程采用非开挖技术施工提供参考. 相似文献
60.
Abstract The aim of this study was to assess the effect of land application of sewage sludge on phosphorus (P) losses during intense rainfall. Three rainfall simulations (40 mm h?1 of 30 min duration) were conducted on a field amended with sewage sludge. The overland flow water (OFW) was monitored and sampled every minute. The suspended solid, the dissolved and total phosphorus (respectively SS, TP and DP) concentrations were analysed. The forms of particulate bound P (PP) were investigated. Several results stem from this experiment: (a) sludge application induced a large increase in the DP content of the OFW; the concentrations obtained (0.15–0.57 mg l?1) were shown to result from desorption processes from the SS; and (b) in contrast, sludge application affected neither the SS content nor the TP concentration of OFW (9.5 g mg l?1 P, consisting of PP for 95%). However, sludge preserved the structure of soil surface and led to a 45% decrease in runoff rate (150 m3 ha?1 collected on the test surface compared to 290 m3 ha?1 on a reference). This indirectly reduced TP losses (2.7 kg ha?1 on the reference surface compared to 1.4 kg ha?1 on the test surface). 相似文献