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人工纳米材料与污水微生物聚集体的相互作用研究

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中国给水排水 2024年第2期40卷 10-17页

作者：尤国祥王超王沛芳陈娟许伊侯俊河海大学环境学院浅水湖泊综合治理与资源开发教育部重点实验室江苏南京210098 河海大学农业科学与工程学院江苏南京210098

近年来,关于人工纳米材料(NMs)在污水处理系统中的生物转化与生物效应研究得到了广泛关注,NMs与污水微生物聚集体的相互作用成为其中的焦点。基于已有研究成果,系统综述了微生物聚集体及其表面胞外聚合物(EPS)对NMs环境行为的影响,进一... 详细信息

近年来,关于人工纳米材料(NMs)在污水处理系统中的生物转化与生物效应研究得到了广泛关注,NMs与污水微生物聚集体的相互作用成为其中的焦点。基于已有研究成果,系统综述了微生物聚集体及其表面胞外聚合物(EPS)对NMs环境行为的影响,进一步总结了NMs对EPS组成与结构特性、微生物聚集体的群落结构及功能活性的影响,从上述两个方面探究了NMs在污水处理系统中的赋存、归趋及生物毒性效应,旨在为深入开展NMs在污水处理系统中的污染控制、风险评价和管理提供理论基础和科学依据。

关键词：微生物聚集体胞外聚合物纳米材料生物效应污水处理系统

WATER QUALITY MODELING AND POLLUTION CONTROL FOR THE EASTERN ROUTE OF SOUTH TO NORTH WATER TRANSFER PROJECT IN CHINA

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Journal of Hydrodynamics 2006年第3期18卷 253-261页

作者： wang Chao wang Yan-ying wang pei-fang Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes College of Environmental Science and Engineering Hohai University Nanjing 210098 China

South to North Water Transfer Project in China is the largest project over centuries to solve the water shortage problem in vast areas of northern China. It comprises of three routes： the eastern, central and western route and this study mainly focused on the eastern route. As water quality is the key factor for the eastern route, this paper examined the main factors influencing water quality of the main route south of the Yellow River, by investigating the point source, non-point source （diffusive source） and internal source pollutions along the main eastern route and in its drainage basins, and assessing the Current water quality in the waterways. According to the complicated and combined systems of rivers and lakes in this route, one-dimensional water quantity and quality model for rivers and two-dimensional model for lakes were developed to simulate the hydrodynamic and pollutant transport processes. The numerical method and model algorithm were described. The values of model parameters were estimated by using field-monitoring data along the main route and the inverse modeling technique. Established models were employed to predict the degradations of CODMn and NH4^＋-N in the main stream, under the conditions of current pollution loads and different hydrologic conditions. Schemes were present for controlling total quantities of pollutants from point source and non-point source along the main route to secure water quality for the eastern route.

关键词： South to North Water Transfer Eastern RouteProject water quality pollution loads pollution control

NUMERICAL MODEL FOR FLOW THROUGH SUBMERGED VEGETATION REGIONS IN A SHALLOW LAKE

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Journal of Hydrodynamics 2011年第2期23卷 170-178页

作者： wang pei-fang wang Chao Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry ot Education College of Environment Hohai University Nanjing 210098 China

Aquatic vegetation has a significant impact on water currents. To evaluate the effects of changes in the aquatic vegetation on water currents of different velocity, a 3-D hydrodynamic model was then developed by taking into consideration of the additional hydraulic resistance of the aquatic plants. The Navier- Stokes equations were then solved using the SIMPLE method and the k - e＂ turbulence model. Calculations using the established models were used to forecast the vertical distribution of the horizontal velocity and horizontal flow under the transmission conditions of the South-North Water Diversion in the Nansi Lake. And comparative calculation for the flow velocity was also performed using the simplified method of assigning a high roughness coefficient to the lake bed in the same area. Results suggest that adding additional hydraulic resistance of the aquatic plants is feasible. The calculation errors between simulation result and the field observed data are smaller than 15%, while, those errors are up to 35% if the influence of aquatic vegetation is dealt with the simplified method.

关键词： lakes numerical models hydraulic resistance aquatic vegetation

FLOW STRUCTURE OF PARTLY VEGETATED OPEN-CHANNEL FLOWS WITH EELGRASS

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Journal of Hydrodynamics 2009年第3期21卷 301-307页

作者： wang Chao YU Ji-yu wang pei-fang GUO Peng-cheng Key Laboratory of Integrated Regulation and Resource Department on Shallow Lakes Ministry of Education Hohai University Nanjing 210098 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210098 China College of Environmental Science and Engineering Hohai University Nanjing 210098 China Yellow River Engineering Consulting Co. Ltd. Zhengzhou 450003 China

Aquatic vegetation can influence the transport of sediment and contaminants by changing the mean velocity and turbulent flow structure in channels. It is important to understand the hydraulics of the flows over vegetation in order to manage fluvial processes. Experiments in an open-channel flume with natural vegetation were carried out to study the influence of vegetation on the flows. In a half channel with two different densities of vegetation, the flow velocity, Reynolds stresses, and turbulence intensities were measured using an Acoustic Doppler Velocimeter （ADV）. We obtained velocity profiles in the lateral direction, Reynolds stresses in the vertical direction, and the flow transition between the vegetated and non-vegetated zones in different flow regimes. The results show that the streamwise velocity in the vegetated zone with higher density is almost entirely blocked. Reynolds stress distribution distinguishes with two different regions： inside and above the vegetation canopies. The turbulence intensities increase with increasing Reynolds number. The coherent vortices dominate the vertical transport of momentum and are advected clockwise between the vegetated zone and non-vegetated zone by secondary currents （a relatively minor flow superimposed on the primary flow, with significantly different speed and direction）, generated by the anisotropy of the turbulence.

关键词： open channel aquatic vegetation velocity profile turbulence characteristics

MODEL OF CALCULATING WATER QUANTITY NEEDED TO DILUTE AND PURIFY POLLUTANTS IN RIVER NETWORK ANDITS APPLICATIONS

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Journal of Hydrodynamics 2005年第4期17卷 418-428页

作者： wang Chao wang pei-fang Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Hohai University Nanjing 210098 China College of Environmental Science and Engineering Hohai University Nanjing 210098 China

Based on the analysis of dilution capacity and self-purification capacity of water body, the dilution, dispersion, entrapping and purification principles of pollutants in river system at river network area were discussed in this paper. Also, the one and two dimensional models of water quantity needed for improving water environment quality and pollutant concentrations were developed for rivers and lakes respectively. The calculation method for the quantity of water transfer was given and the forecasting evaluation of the effect of water transfer was carried out. It was took the project, water transfer from Yangtze River to improve the water quality of rivers in Zhangjiagang City, as an example, and changing principles of water quantity and quality were observed in rivers and lakes through site water transfer experiments. The theory of estimating parameters in inverse problem was used to determine parameters in water quantity and quality models. The water quantity and quality coupled models in river system were applied to calculate the minimal water transfer quantity. The theoretical and technical support for the improvement of water environmental quality in Zhangjiagang City and the project ＂water transfer form Yangtze River to Taihu Lake＂ were provided.

关键词： river network dilution purification mathematical models site observation

EXPERIMENTAL STUDY ON SEDIMENT RESUSPENSION IN TAIHU LAKE UNDER DIFFERENT HYDRODYNAMIC DISTURBANCES

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Journal of Hydrodynamics 2011年第6期23卷 826-833页

作者： QIAN Jin ZHENG Sha-sha wang pei-fang wang Chao Key Laboratory of Integrated Regulation and Resource Department on Shallow Lakes Ministry of Education and College of Enviroment Hohai University Nanjing 210098 China

Contaminants resuspension in sediments induced by wind-wave could influence the water quality in shallow lakes. Resuspension of surface sediments from the Zhushan Bay, Taihu Lake was simulated under different wind forcing by using a pneumatic annular flume in this study. Acoustic Doppler Velocimeter （ADV） was used to measure flow velocity at each wind speed, and the characteristics of sediment resuspension were studied with the layered sampling technology. The experimental results show that the flow velocity increases with wind speed obviously and 6m/s is a critical wind speed which affected hydrodynamic conditions significantly. The distribution of flow velocity and water depth is different from that in ordinary open channel. With the enhanced hydrodynamic factors, the Suspended Solids Concentration （SSC） in water increases accordingly, and the incipient velocity of sediment resuspension is about 0.21 m/s. Based on the analysis of wind speed and average SSC in water column, the quantitative relationship is obtained. The SSC of the bottom layer is higher than the content of surface layer under different hydrodynamic conditions, and there are similar distributions between SSC and flow velocity in different water layers.

关键词： hydrodynamic disturbance sediment resuspension wind speed flow velocity

EFFECTS OF AQUATIC VEGETATION ON FLOW IN THE NANSI LAKE AND ITS FLOW VELOCITY MODELING

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Journal of Hydrodynamics 2006年第6期18卷 640-648页

作者： wang Chao ZHU Ping wang pei-fang ZHANG Wen-ming Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of EducationCollege of Environmental Science and Engineering Hohai University Nanjing 210098 China

Aquatic vegetation has significant effects on flow in waters. In this article, four types of water areas were analyzed according to the field survey on water depth and vegetation in the Nansi Lake for the East Line Project of Water Transfer from South to North in China （WTSNC）. The depth-averaged 2-D hydrodynamic models with and without consideration of the effects of aquatic vegetation on flow were established to simulate flow fields in vegetated and non-vegetated zones in the Nansi Lake. With the established models, flow fields were predicted under the conditions of water transfer from south to north. The results indicate that when the drag force term exerted by aquatic vegetation is considered, the computed velocities agree well with the measured data, whereas as the drag term is taken into account, the computed velocities are obviously larger than the measured data in the vegetated zone and considerably smaller in the non-vegetated zone, and the error range between the two velocities is large if this problem is dealt with the method of increasing the roughness coefficient of the lake-bed to reflect the vegetation drag force. In addition, it is demonstrated that the emerged vegetation exerts larger effects on flow than submerged vegetation comparing the results in the Emerged Vegetation （reed） Zone （EVZ） and the Submerged Vegetation Zone （SVZ）.

关键词： Nansi Lake aquatic vegetation drag force,flow modeling

Migration of Infiltrated NH_4 and NO_3 in a Soil and Groundwater System Simulated by a Soil Tank

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Pedosphere 2008年第5期18卷 628-637页

作者： wang Chao wang pei-fang State Key Laboratory of Hydrology- Water Resources and Hydraulic Engineering Key Laboratory of Integrated Regulationand Resource Department on Shallow Lakes Ministry of Education Environmental Science and Engineering CollegeHohai University Nanjing 210098 （China）.

The infiltration of water contaminants into soil and groundwater systems can greatly affect the quality of groundwater. A laboratory-designed large soil tank with periodic and continuous infiltration models, respectively, was used to simulate the migration of the contaminants NH4 and NO3 in a soil and groundwater system, including unsaturated and saturated zones. The unsaturated soil zone had a significant effect on removing NH4 and NO3 infiltrated from the surface water. The patterns of breakthrough curves of NH4 and NO3 in the unsaturated zone were related to the infiltration time. A short infiltration time resulted in a single sharp peak in the breakthrough curve, while a long infiltration time led to a plateau curve. When NH4 and NO3 migrated from the unsaturated zone to the saturated zone, an interracial retardation was formed, resulting in an increased contaminant concentration on the interface. Under the influence of horizontal groundwater movement, the infiltrated contaminants formed a contamination-prone area downstream. As the contaminants migrated downstream, their concentrations were significantly reduced. Under the same infiltration concentration, the concentration of NO3 was greater than that of NH4 at every corresponding cross-section in the soil and groundwater tank, suggesting that the removal efficiency of NH4 was greater than that of NO3 in the soil and groundwater system.

关键词： breakthrough curve migration NH4 NO3 soil tank experiment

Extractable Fractions of Metals in Sewage Sludges from Five Typical Urban Wastewater Treatment Plants of China

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Pedosphere 2006年第6期16卷 756-761页

作者： wang Chao LI Xiao-Chen wang pei-fang ZOU Li-Min MA Hai-Tao Key Laboratory of Integrated Regulation and Resource Department on Shallow Lakes Ministry of Education Nanjing 210098 China School of Environmental Science and Engineering Hohai University Nanjing 210098 China

Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in China to investigate their contents and distribution of various chemical fractions of Cu, Zn, Ni, Cr, Pb and Mo by using the BCR （Community Bureau of Reference） sequential extraction procedure. The sludges contained considerable amounts of organic matter （31.8%- 48.0%）, total N （16.3-26.4 g kg^-1） and total P （15.1-23.9 g kg^-1）, indicating high potential agricultural benefits of their practical applications. However, total Zn and Ni contents in the sludge exceeded the values permitted in China＇s control standards for pollutants in sludges from agricultural use （GB 4284-1984）. The residual fraction was the predominant fraction for Mo, Ni and Cr, the oxidizable fraction was the primary fraction for Cu and Pb, and the exchangeable and reducible fractions were principal for Zn. The distribution of different chemical fractions among the sludge samples refiected differences in their physicochemical properties, especially pH. The sludge pH was negatively correlated with the percentages of reducible fraction of Cu and exchangeable fraction of Zn. The sludges from these plants might not be suitable for agricultural applications due to their high contents of Zn, Ni and Cr, as well as high potential of mobility and bioavailability of Zn.

关键词： fractions heavy metals sequential extraction sewage sludge