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采用絮凝沉淀-活性污泥法-接触氧化法组合工艺处理制革废水,工程规模250 m3/d,水质复杂变化大,且毒性较大.该工艺自2003年12月投产至今处理效果稳定,进水CODCr为3000~3 500mg/L时,出水CODCr约40 mg/L,CODCr去除率可达98%,各项出水指标均达到广东省地方标准<水污染物排放限值>(DB 44/26-2001)一级标准. 相似文献
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洗涤剂废水处理工程实例 总被引:1,自引:0,他引:1
采用混凝沉淀-水解酸化-好氧移动床生物膜工艺处理含生物毒性成分的洗涤剂废水。运行结果表明,设计处理水量为450 m3/d,进水中CODCr、BODs、SS、LAS、TCC-TCS的浓度为1 432 mg/L, 467 ms/L,430 mg/L,183 mg/L和35 mg/L时,处理后出水浓度分别降至90 mg/L,21 mg/L,32 mg/L, 5 mg/L和0 mg/L。出水水质达到《污水综合排放标准》(GB 8978-1996)的二级标准。处理工艺具有处理效果好、运行稳定且操作维护方便等特点。 相似文献
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广东某制药公司的抗生素废水具有高毒性、难降解等特点,采用常规生物处理方法难以处理.利用Fenton法预处理抗生素废水,减小抗生素废水的生物毒性并改善其可生化性后,将Fenton池出水与厂区清洗废水混合,进入物化生化组合工艺处理.最终出水水质指标中,BOD5为76.56 mg/L,COD 为168.91 mg/L,SS 为27.67 mg/L,氨氮为14.51 mg/L,磷酸盐0.1 mg/L,pH 的控制值在6?7,各项指标均达到了广东省《水污染物排放限值》(DB 44/26-2001)的水质要求. 相似文献
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某制药厂生产废水水质变化大,污染物浓度高,毒性大.采用气浮—兼氧-CASS工艺进行处理.实践表明,处理出水COD 450~650 mg/L,氨氮20~35 mg/L,BOD5≤100 mg/L,SS50~100mg/L,可达《污水综合排放标准》(GB 8978-1996)三级排放标准. 相似文献
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污水再生处理微滤-反渗透工艺运行效果分析 总被引:1,自引:0,他引:1
随着高水质要求用户对再生水需求的增加,微滤/超滤(MF/UF)与反渗透(RO)组合而成的双膜过滤工艺在污水再生处理领域的应用受到关注。根据北京市某再生水厂微滤—反渗透(MF—RO)工艺的长期运行数据,评价了COD、NH3—N、TP、SS等水质指标的去除效果。结果表明再生水厂进水(即上游污水处理厂出水)水质总体较好,以生物处理为主的上游污水处理厂可以有效去除污水中的颗粒污染物、有机污染物、NH3—N、TP等,但NH3—N、TP的处理效果存在季节性变化。经MF—RO工艺处理的出水COD平均为0.45mg/L,87.7%的出水NH3—N低于检测限(0.2mg/L),98.8%的出水TP不超过0.01mg/L,出水浊度的平均值为0.064NTU,出水平均TDS为30.8mg/L。出水水质好且稳定,受进水水质和季节变化影响较小,但pH主要分布在5.5~6.0的范围内,需要投加碱调节pH以保证水质稳定性。 相似文献
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《给水排水》2014,(9)
正As the eldest and most distributed professional journal of water industry,Water Wastewater Engineering(W WE)gained very wide acceptance from the colleagues working in this field in this country since start publication in 1964.Now it is administrated by the Ministry of Construction of the People’s Republic of China and sponsored by the China Civil Engineering Society etc. 相似文献
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根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。 相似文献
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Samples were taken year-round at eleven sites along the altitudinal profile (2900-1400 m a.s.l.) of the Gunnison River, a 329 km tributary of the Colorado River, to document the distribution of the Plecoptera and to evaluate responses to hypolimnial-release dams in the headwaters and middle reaches. Twenty-two species were present, with the greatest species richness occurring in an unregulated segment upstream of the middle reach dams; average nymphal biomass over the study period (175 organisms, 395 mg dry mass m?2) was also greatest in this segment. Only four species (58 organisms, 48 mg m?2) were present in the tailwaters of the headwater dam and values were greatly reduced (nine species; 35 organisms, 180 mg m?2) below the middle reach dams. The stonefly community recovered ca. 80 km downstream from the last dam (15 species; 244 organisms, 250 mg m?2), apparently in response to natural resetting of environmental conditions corresponding to those above the middle reach dams. At the most downstream site (11) only four species (four organisms, 16 mg m?2) were present. The observed distributional pattern is a classic serial discontinuity in response to hypolimnial stream regulation in a temperate latitude river. 相似文献
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Tracey Magrann Stephen G. Dunbar Danilo S. Boskovic William K. Hayes 《Lakes & Reservoirs: Research and Management》2012,17(3):231-239
Cyanobacteria often dominate eutrophic lakes, outcompeting green algae that are required by fish and zooplankton. This study was undertaken to ascertain the impact of the cyanobacterium, Microcystis, on algal biodiversity. Under laboratory conditions, we found that the presence of Microcystis decreased phyla richness by 58%, phyla evenness by 47%, genera richness by 66% and genera evenness by 51%. Analysis by mixed anova s demonstrated a significant interaction between treatment and time and confirmed a significant reduction in richness and evenness of phyla and genera. We also conducted a phosphate restriction assay on the algae in Mason Lake (Irvine, CA, USA) and found that the threshold needed for algal growth there was 0.02 mg L?1 PO4. A pilot study was then conducted to test the effectiveness of the Blue Pro? water treatment facility in removal of this colonial organism from Mason Lake, in addition to removal of dissolved nutrients required for its growth. We measured a 97% reduction in Microcystis cells, a 72% reduction in chlorophyll‐a, and a 96% reduction in phosphate after just one 10 min cycle through the unit. Our study demonstrated that removal of Microcystis colonies may allow green algae to increase in numbers. This may improve algal biodiversity, which will benefit zooplankton and fishes. 相似文献
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The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects. 相似文献
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解析法是库岸边坡地下水浸润线计算中便于实际应用的方法,但该方法须基于若干假定并对潜水运动基本方程线性化后才能求解。针对各假定和线性化过程建立不同的地下水渗流数学模型,用解析法和有限元法解答上述数学模型,分析各误差大小及其规律。结果表明:库岸垂直处理带来的误差要小于方程线性化处理和不考虑非饱和渗流带来的误差,而且它们都随渗透系数变大而减小;在三峡库区库水调度情况下,假定库水位等速变化带来的误差对大多岸坡而言可以忽略;计算库岸边坡地下水浸润线时,解析法只适用于水位变化幅度相比含水层厚度较小,且几何边界规则、岩土结构简单、岩土体渗透性较好时的情况。 相似文献
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The floodplains of lowland rivers contain diverse aquatic habitats that provide valuable ecosystem services but are perturbed when intensively cultivated. Hydrologic, water chemistry and biological (fish) conditions in five aquatic habitats along the Coldwater River, Mississippi, were measured for more than 4 years: the river, two severed meanders that functioned as backwaters, a managed wetland and an ephemeral channel draining cultivated fields. Off‐channel habitats were connected to downstream regions 0.10% to 32% of the dry season and 24% to 67% of the wet season. The median temperatures for the five monitored sites ranged from 18°C to 23°C, the median total solids concentration for all sites was 135 mg L?1, the median total phosphorus was 0.29 mg L?1 and the median total nitrogen was 1.56 mg L?1. Chemical and physical water quality displayed strong seasonal differences between the wet winter/spring and the dry summer/fall periods so that temporal variation consisted of gradual seasonal trends superimposed on strong diurnal variations. All off‐channel habitats exhibited periods of hypoxia and temperatures >30°C during the dry season. Between‐site gradients of water and habitat quality were strongly coupled to water depth and runoff loading. The rehabilitation of one backwater by increasing water depth and diverting agricultural runoff was associated with improved water quality and fish species richness relative to an adjacent untreated backwater. The diversion of polluted runoff and the use of water control structures to maintain greater water depth were observed to be effective management tools, but the former reduces the water supply to habitats that tend to dry up and the latter reduces connectivity. Published in 2011 by John Wiley & Sons, Ltd. 相似文献
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Mutlu Ozdogan Curtis E. Woodcock Guido D. Salvucci Hüseyin Demir 《Water Resources Management》2006,20(3):467-488
Changes in summer irrigated cropland acreage and related water use are estimated from satellite remote sensing and ancillary
data in semi-arid Southeastern Turkey where traditionally dry agricultural lands are being rapidly transformed into irrigated
fields with the help of water from the Euphrates-Tigris Rivers. An image classification methodology based on thresholding
of Landsat NDVI images from the peak summer period reveals that the total area of summer irrigated crops has increased three-fold
(from 35,000 ha to over 100,000) in the Harran Plain between 1993 and 2002. Coupled analysis of annual irrigated crop area
from remote sensing and potential evapotranspiration based estimates of irrigation water requirements for cotton indicate
a corresponding increase in agricultural water use from about 370 million cubic meters to over one billion cubic meters, a
volume in accordance with the state estimates. These estimates have important implications for understanding the rapid changes
in current agricultural withdrawals in Southeastern Turkey and form a quantitative basis for exploring the changes in future
water demands in the region. For example, expansion of irrigated lands have led to a steady decrease in potential evaporation
due to increased roughness and decreased humidity deficit in the Harran Plain. Assuming that the changes in future evaporation
conditions will be of similar nature, water use for irrigation is expected to decrease over 40 percent in future irrigation
sites. Incorporating this decrease in overall planning of the irrigation projects currently under construction should lead
to improved management, and by extension, sustainability of water resources in the region. 相似文献
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簸箕李引黄灌区水沙分布及优化调度的经验 总被引:1,自引:0,他引:1
灌区利用水沙观测所取得的资料和试验数据,运用水沙运动力学理论,总结分析和揭示了灌区水沙分布的规律和特点。在此基础上,结合灌区的实际运行情况,围绕减少骨干渠道的淤积进行探讨、研究,进而,优化水沙调度方案。该方案实施后,骨干渠道减旅伴效果明显,取得了成功的经验。 相似文献