再生颗粒活性炭在果园桥水厂的应用实践

桐乡市果园桥水厂采用臭氧-生物活性炭深度处理工艺,为了强化处理效果、降低制水成本、减少环境污染,对饱和生物活性炭进行了再生.通过检测,再生炭的碘值恢复率达90%以上,亚甲基蓝值恢复率接近90%,强度略有下降,但仍高达93%,灰分增长了91.5%.再生炭运行当月CODMn去除率高达78.4%,运行半年至今去除率仍达50%左右,处理效果接近新炭水平.采用再生方式比全部更换新炭节省费用50%以上.最后阐述了饱和活性炭再生利用的可行性及必要性.     

活性炭放电再生的试验研究

介绍活性炭放电再生法的再生机理、特点及对颗粒活性炭的再生试验,最后利用单宁酸对再生活性炭再吸附效果进行了检验.结果显示:碘值恢复率≥95%;再生损耗率≤5%;再生时间5～10 min;再生能耗＜860 kcal/kg GAC;再吸附恢复率接近或超过100%,再生装置结构紧凑,适用于饱和活性炭的就地再生.     

颗粒活性炭在净水厂中的使用性能分析

针对北方某大型净水厂3种不同炭龄的颗粒活性炭,对其物理特性和典型水质指标去除效果进行研究,结果表明,颗粒活性炭使用5年后,其吸附值等物理特性趋于稳定;颗粒活性炭表面的酸杆菌、根瘤菌等微生物对去除水中有机物发挥了重要作用;碘吸附值和亚甲基蓝吸附值不是颗粒活性炭再生更换的主要指标;可考虑延长新炭再生时间至5年。     

活性炭再生及新技术研究

活性炭是一种大量消耗资源的产品 ,其再生工艺分为药剂洗脱的化学法、生物再生法、湿式氧化法、电解氧化法、加热再生法等。介绍了一种新型的高温加热再生方法———放电高温加热再生法 ,它能够在 5～ 10min完成升温、干燥、焙烧、活化的过程 ,使活性炭达到再生 ,炭损耗率小于2 % ,碘吸附恢复率达到 95 %。     

活性炭吸附性能新指标在实际水处理工艺中的应用

以单宁酸和腐殖酸吸附值作为活性炭吸附性能新指标进行生产性试验的验证,在建立生物活性炭吸附作用模型的基础上,对工艺运行60 d内活性炭的有机物吸附值(UV254和CODMn)进行了曲线拟合,结果较好地符合吸附模型,相关系数R2为0.606 4~0.786 1。对工艺中选取的5种活性炭进行有机物吸附试验,将吸附容量与传统选炭指标碘吸附值和亚甲基蓝吸附值,以及新指标单宁酸和腐殖酸吸附值进行相关性分析。结果表明传统指标与5种活性炭生产试验中的吸附容量之间不存在明显的相关性,而新指标与5种活性炭的吸附容量之间有较好的相关性:以UV254的变化值表示活性炭的吸附容量时,单宁酸及腐殖酸吸附值与其的相关系数R2分别为0.705 4和0.816 9;以CODMn的变化值表示活性炭的吸附容量时,单宁酸及腐殖酸吸附值与其的相关系数R2分别为0.632 5和0.701 3。     

污泥活性炭对亚甲基蓝吸附性能的研究

以城市污水处理厂剩余污泥和玉米秸秆为原料,采用化学活化法,在氯化锌浓度为3mol/L,活化温度为600℃,活化时间为1h的条件下制备出污泥活性炭。对污泥活性炭进行了电镜扫描(SEM)、孔结构分析和傅立叶光谱(FTIR)进行了表征。结果表明,污泥活性炭的碘值为359.2mg/g,BET比表面积为173.7m~2/g,平均孔径为9.776nm,活性炭中出现了羟基、酚羟基、氨基等基团。当吸附时间为6h,温度为35℃时,亚甲基蓝的去除率最佳;随着pH的升高,亚甲基蓝的去除率也随之升高。污泥活性炭对亚甲基蓝的吸附符合Langmuir吸附等温线和Lagergren准二级动力学方程。     

木质纤维素对水溶液中亚甲基蓝的吸附性能

以木质纤维素为吸附剂,分析吸附时间、初始浓度、pH值、温度等因素对木质纤维素吸附亚甲基蓝阳离子染料的影响.结果表明:木质纤维素对亚甲基蓝吸附300min后达到平衡,初始浓度超过180mg/L后吸附量不再增加,pH值由2增加到8时,吸附量由23.0mg/g增加到40.1 mg/g,温度对吸附量呈现先增大后减小的趋势.讨论...     

脱硫废液吸附净化中活性炭再生可行性研究

研究了通过乙醇萃取处理脱硫废水中活性炭再生方法的可行性。通过试验得出:新活性炭与再生后对苯酚的吸附容量分别为14.09mg/g和1.07mg/g,再生效率为7.6%;而其再生前后对脱硫废液的吸附容量分别为540mg/g和200mg/g,再生效率为37%。通过经济评价估算,活性炭按3 000元/t计,再生一次较经济,可节约成本1 200元,乙醇萃取再生活性炭的方法可行。     

吸附Cr活性炭再生试验研究

通过不同化学方法对吸附Cr活性炭进行再生试验研究,选出效果较好的方法.在相同的条件下,分别采用电化学法、化学药剂方法、电化学药剂结合法再生吸附Cr的饱和活性炭,并对上述方法得到的结果进行比较分析.试验结果表明,硝酸法再生吸附Cr活性炭具有较好的再生效果,在一定条件下,活性炭再生率达124.9%.通过SEM图像对比分析得出,经HNO_3再生后,活性炭表面孔径得到明显改善,与其他几种再生方法相比,HNO3再生后活性炭表面结构和表面特性较好.     

活性炭吸附法处理电镀含铬废水

我院自1976年以来,先后作了活性炭吸附法处理含铬废水的小型、中型试验,并在庆华电器制造厂的生产运行中取得了一定的效果。证明活性炭不仅能吸附六价铬,且去除率可达99％以上,出水完全可以达到排放标准。通过流程设计,还可实现漂洗水的封闭循环。活性炭吸附六价铬达饱和后,可通过碱法再生,酸“活化”,恢复吸附性能,继续用于吸附处理。在再生饱和炭中,可获得解吸下的铬酸盐,回用于生产。我们在庆华厂采用了槽边直接处理,双炭柱吸附装置(图1)。由水泵直接抽取电镀漂洗槽之废水,经Ⅰ、Ⅱ炭柱逆流吸附后,仍回用于漂洗槽。炭柱Ⅰ,Ⅱ均为有机玻璃,φ170毫米,高1.50米,每     

Call for Papers

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.     

地下厂房施工过程的三维非线性数值模拟分析

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。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

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.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

SPATIAL AND TEMPORAL WATER QUALITY VARIABILITY IN AQUATIC HABITATS OF A CULTIVATED FLOODPLAIN

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.     

库水波动下库岸边坡地下水浸润线解析解及误差分析

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。     

Changes in Summer Irrigated Crop Area and Water Use in Southeastern Turkey from 1993 to 2002: Implications for Current and Future Water Resources

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.     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Spatio‐temporal variation of gross CO2 and CH4 diffusive emissions from Australian reservoirs and natural aquatic ecosystems,and estimation of net reservoir emissions

Carbon dioxide (CO₂) and methane (CH₄) diffusive emissions were measured during two field surveys in Queensland and Tasmania, Australia, using the floating chamber method. Bubbling and degassing emissions in 2010 were estimated in Koombooloomba Dam reservoir using only inverted funnels and gas concentrations, respectively. A total of 14 reservoirs and 16 rivers and lakes were sampled from 2006 to 2010. Spatial variation was substantial within each water body, as well as between them. The main drivers of diffusive emission variation were physiographic region and climate, with a clear demarcation being observed between diffusive emissions from tropical Queensland and temperate Tasmania, and between the humid West Coast Range (Tasmania) and dry Central Plateau (Tasmania). Higher CO₂ and CH₄ diffusive emissions were observed during the dry season, when long water residence times would promote organic matter degradation. Estimated total gross emissions, including diffusive, bubbling and degassing emissions, for Koombooloomba Dam reservoir were about 1.5 × 10⁶ t CO₂eq km² per year, or 24 × 10⁶ t CO₂eq per year. This corresponds to a plant emission factor of 3.18 kg CO₂eq MWh^?1. Using an estimate of terrestrial emissions derived from literature data for the Tully River catchment area, rough estimated net emissions from the catchment area are about 44 kt CO₂eq per year, or 5.83 kg CO₂eq MWh^?1, which is in the lower range of the studied reservoirs.     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.