硅酸锌催化臭氧氧化净水效能连续流实验研究

以实验室制备的硅酸锌为催化剂,考察了在连续流实验中催化臭氧氧化对滤后水水质的影响。结果表明,与单独臭氧氧化相比,在相同实验条件下,硅酸锌的存在能够提高水体中的臭氧浓度。硅酸锌催化臭氧氧化对滤后水的总有机碳(TOC)和天然有机物的去除效果均好于单独臭氧氧化。连续运行10 h,硅酸锌催化臭氧氧化系统中TOC的去除效果稳定,并且Zn2+的溶出非常少。生物可同化性有机碳(assimilable organic carbon,AOC)的测定结果表明,经过硅酸锌催化臭氧化处理后,滤后水中的大分子有机物所占比例明显降低,小分子有机物含量增高。GC-MS分析结果表明,单独臭氧氧化可使滤后水中有机物的种类从41种减少到27种;而硅酸锌催化臭氧化效果明显优于单独臭氧氧化可以使水中有机物种类减少到21种。     

饮用水处理工艺去除两种典型内分泌干扰物的性能

研究了水中两种典型内分泌干扰物———双酚A(BPA)和邻苯二甲酸二甲酯(DMP)在饮用水常规处理、臭氧活性炭和微曝气活性炭深度处理中试工艺中的去除性能。研究发现,饮用水常规处理工艺对BPA和DMP的去除效果有限,进水浓度为200~300μg/L条件下经过混凝、沉淀和砂滤后,BPA和DMP的去除率分别仅为25.38%和13.29%。臭氧活性炭深度处理工艺能有效去除BPA和DMP,但二者在该工艺中的去除特性有所不同:水中BPA经过臭氧氧化后几乎被全部去除,后续的生物活性炭处理单元作用较小;但臭氧氧化仅可部分去除DMP,大部分靠后续生物活性炭柱去除。微曝气活性炭深度处理工艺也能有效去除BPA和DMP,对二者的去除主要靠微曝气活性炭柱的作用,其效果略优于臭氧投加量为0条件下的臭氧活性炭柱,这说明微曝气活性炭柱存在较多的特定降解菌。通过静态吸附试验发现,臭氧活性炭柱和微曝气活性炭柱内活性炭对BPA和DMP的最大吸附容量均远小于新炭,同时臭氧活性炭柱内活性炭吸附容量略高于微曝气活性炭柱。     

有机物相对分子质量分布对O3-GAC工艺中臭氧投加量的影响

采用滤膜法测试了不同臭氧投加量下,臭氧活性炭出水中的有机物相对分子质量分布的特性,并对其去除情况进行了分析.结果表明,相对分子质量小于1 000的有机物易被臭氧氧化为C02和H2O而去除.大于10 000的大分子有机物被氧化分解为3 000～10 000的小分子有机物,这部分小分子有机物可被后续活性炭生物降解去除.增加臭氧投加量,大于30 000的有机物被氧化为相对分子质量分布范围更广的小分子有机物,使大于30 000的有机物易被活性炭降解,但会使小于1 000的有机物的去除效果降低.臭氧投加量的确定应考虑水中有机物相对分子质量分布情况.     

催化臭氧化——一种有前景的水处理高级氧化技术

介绍了均相和非均相催化剂增加臭氧氧化去除水溶液中有机物的效率 ,催化臭氧化能够氧化或降解单独臭氧不能氧化或降解的难降解有机物 ,减少后续氯化消毒工艺所形成消毒副产物如三氯甲烷等的含量     

剩余臭氧影响活性炭净水效能原因分析

通过中试分析了长期运行条件下臭氧—活性炭工艺中溶解性臭氧对活性炭净水效能产生影响的原因。试验条件下活性炭对UV254的去除能力随剩余臭氧浓度的增加而下降。根据试验推测臭氧对活性炭的影响主要体现在3个方面:首先,在臭氧投加量较高时,NOM中亲水性有机物比例增加,此类物质在活性炭上的吸附性较差;其次,臭氧氧化降低了活性炭的吸附能力,同时臭氧可能与活性炭反应生成新的氧化产物;最后,臭氧可抑制活性炭上微生物的生长繁殖。因此建议在臭氧—活性炭工艺运行时严格控制进入活性炭吸附池的剩余臭氧浓度。     

臭氧催化氧化改善水质安全性指标中试与生产性研究

从水的生物稳定性、遗传毒性、颗粒物去除、臭氧氧化副产物以及催化剂的稳定性等方面研究了臭氧催化氧化-生物活性炭技术在净水处理过程中的安全性问题.结果表明,催化剂具有优良的物理化学稳定性,能够催化臭氧氧化进一步控制AOC及其前质,减小了活性炭的污染物负荷;与生物活性炭联用可以明显减小有害有机物穿透水处理工艺的能力,进一步消减了水的遗传毒性;联用工艺可以显著地去除水中与致病原生动物相关性极大的2～10 μm颗粒物,进一步提高了饮用水的卫生安全性;催化剂对剩余臭氧的消减抑制了BrO-3生成.     

饮用水深度净化工艺现场对比试验

考察了实际生产规模的臭氧粒状活性炭工艺以及小型超滤、纳滤、反渗透膜法两种典型饮用水深度净化工艺的处理效果。试验结果发现臭氧活性炭工艺具有优良、稳定的去除有机污染物功能,而孔径较小的活性炭纤维除污染效果并不好,臭氧氧化出水、超滤出水再用压缩活性炭进行吸附处理对有机物的去除效率要比直接处理原水高。超滤膜除有机物效率不高,而反渗透和纳滤膜在较好地去除水中有机物的同时,也去除了水中绝大部分无机物,出水有机物和无机物浓度都比较低。     

臭氧-活性炭工艺去除饮用水中典型内分泌干扰物试验研究

通过对臭氧-活性炭工艺和活性炭吸附等温线的研究,探讨了臭氧-活性炭工艺去除饮用水中微量典型内分泌干扰物的可行性.壬基酚(NP)、辛基酚(OP)和双酚A(BPA)被选作目标物质.研究发现臭氧氧化能去除30%以上的NP、OP和BPA;活性炭对NP、OP和BPA也有良好的去除效果,在空床停留时间4～12 min条件下能完全去除水中未被臭氧氧化的NP、OP和BPA;吸附等温线的数据可以用Freundlich公式拟合,并用来估算活性炭的饱和时间.试验证明臭氧-活性炭工艺是去除饮用水中微量典型内分泌干扰物的有效方法.     

臭氧在生物活性炭工艺中作用的中试研究

为验证臭氧在生物活性炭工艺中所起的作用,在中试系统上考察了生物活性炭与臭氧生物活性炭工艺对原水有机物的去除效能.结果表明,臭氧生物活性炭工艺对CODMn、UV254、BDOC和AOC的去除率比生物活性炭工艺分别高出21%、37.28%、10%和26.4%.在生物活性炭前设置臭氧工艺不仅能够有效降低出水中的有机物含量,而且可以在较低投氯量的条件下使细菌的致死率达到近100%.因此,为更好地发挥生物活性炭在水处理中对有机物的去除作用,应在生物活性炭前增设臭氧工艺.     

臭氧催化氧化应用于工业园区污水处理厂深度处理工艺的选择及设计

污水处理厂深度处理中增设臭氧催化氧化单元可将二级生化出水中的难降解有机物转化为小分子有机物,提高BOD_5/COD,结合后续的工艺(如BAF、活性炭)可保证出水达标排放。分析对比了近年来工程中常用的臭氧氧化、Fenton氧化等高级氧化技术,结合工程设计案例分析臭氧催化氧化的效果,为臭氧催化氧化技术的应用提供参考。     

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。     

Serial discontinuities in a Rocky mountain river. I. Distribution and abundance of plecoptera

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.     

Impacts of Microcystis on algal biodiversity and use of new technology to remove Microcystis and dissolved nutrients

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.     

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.     

簸箕李引黄灌区水沙分布及优化调度的经验

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。     

小湾水库大坝防渗面板及其裂缝的加固处理

小湾水库大坝防渗面板整体抗渗性能差,且存在多条裂缝,通过对面板钢丝网喷涂丙乳砂浆加固处理及其裂缝修补,大坝渗漏量明显减少,且左岸上灌浆廊道内及大坝下游坝面92～93 m高程下廊道入口处原有小股射流全部消失.     

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.