溶解氧在河流水质污染中的作用与分析

近年来,河流水污染现象越来越严重,这其中有机污染占的比例很大。有机污染的河流,由于污染物分解耗氧,水中溶解氧迅速下降,从而导致水质污染恶化,河流水体的自净能力下降,造成水生态系统严重破坏。在河流水质污染中,溶解氧、微生物、污染物三者之间有着密切的关系,通过分析溶解氧、有机物、微生物之间关系,研究分析溶解氧在河流水体自净中所起的作用,建立合适的BOD-DO水质模型,可以帮助河流水生态系统进行修复,也可以对水质预测、水质规划、地方水污染排放标准的制定和水质预警预报等方面发挥重要作用。     

曝气复氧技术在广东地区河流水质污染治理中的应用研究

在对广东地区河流水质污染治理问题进行研究的过程中对曝气复氧技术应用进行了试验研究.构建了人工模拟河道,构建的河道模拟反应器长为3.0m、高为1.2m、宽为0.5m,能够达到1m的有效水深.通过曝气复氧技术对广东地区污染河流水质进行处理,确定曝气运行的最佳方式以及曝气的最佳强度,并对最佳生物填料进行筛选等.结果表明生物膜净化与曝气技术具有良好的河流水质污染治理效果,并且对于较慢流速的水体治理效果更好;弹性填料更适用于广东地区的河流水质污染治理,同时可以将卵石作为治理中的辅料;对于不同污染物而言,需要选择不同曝气方式;曝气强度的最佳选择为中度曝气;加入适量活性污泥能够带来更好的水质污染治理效果,最适当的活性污泥加入量为10％.曝气复氧技术在广东地区河流水质污染治理中的应用前景良好,应着手进行推广.     

好氧与厌氧交替的活性污泥系统

好氧与厌氧交替的活性污泥系统(AAACMAS)是这样一种系统:在该系统中,空气间隔地供入曝气池,从而形成一个氧化含碳基质和有机物或氨氮的好氧单元,与反硝化的厌氧单元交替的运行过程。本系统采用氧传感器而不是由时间继电器控制好氧和厌氧工况,而且人流和出流是连续的。现有处理厂的活性污泥系统略施改造便可成为     

一元稳态河流水质模型

<正> 本文提出一个以Streeter—Phelps方程为基础的、预测污水排入河流引起河流水质特征变化的一元水质数学模型。该模型适用于(1)难易降解的物质;(2)沿岸径流带入的污染物;(3)氮;(4)河流的氧亏量;(5)大肠杆菌总数和(6)正磷酸盐磷。本模型可用于模拟假定上游来水量和污水入流是稳定的任何一元河流的水质情况。稳态     

间歇式活性污泥法处理制革废水的生产性试验研究

本文介绍了间歇式活性污泥法(简称SBR)处理制革废水的生产性试验研究.首先,对SBR工艺在国内外的研究与应用现状进行了概述,简要介绍了本研究的试验设备与方法;然后,对有机物的降解规律和活性污泥增长规律进行了研究与分析.讨论了运行方式、水温、pH值、有机负荷率、污泥龄等因素对有机物降解的影响.根据试验结果,提出了可供同行业采用SBR工艺处理废水时参考的各项主要工程设计与运行控制参数.进行了SBR工艺处理制革废水的动力学分析;从而,定量地描述了有机物降解及活性污泥增长规律.本研究还采用一种动态测定耗氧速率(简称OUR)的方法,用该法探讨了SBR反应阶段的OUR     

影响河流水质因素分析

河流水质会受到点源及非点源污染多种因素的影响,特别是非点源污染与水文循环密切相关。河流水质的污染程度不仅与污染物有关,也与污染物的迁移转化及河流水体的自净作用有关。建立和选择合适的河流水质模型,是定量分析河流水质的基本途径。     

黄河流域水污染日趋严重

根据1981—1990年的黄河水质监测资料分析,黄河流域大夏河和洮河以下各主要河流的水质呈不断恶化趋势。耗氧有机物和氮类污染物大范围急剧增长,挥发酚及汞等污染物在多数河段未得到有效控制,并在一些河段迅速升高。黄河干流自刘家峡水库以下,主要污染物质为汞、耗氧有机物及挥发酚、石油类等。近     

QUAL2E模型在呼和浩特市水质模拟中的应用

呼和浩特市的地表水系由黄河干流和支流组成,以支流为主,整个地表水系统呈树枝状分布,水质污染严重。建立了呼和浩特市的河流水质模型,选用BOD5,CODMn作为模拟污染指标,给出模型关键参数的确定方法,应用QUAL2E模型进行河流水质模拟分析,检验QUAL2E模型参数。模拟结果表明,模型合理有效,能很好地描述河流的水质状况,可进一步为水环境规划提供有利工具和科学的参数依据。     

底泥对河流水质影响的数学模型研究进展

从底泥耗氧、底泥污染物的释放这两方面综述了底泥对河流水质影响的模型研究。通过总结底泥污染河流的模型研究，提出耦合底泥河流水质模型的发展方 向，指出建立环境疏浚模型的必要性。     

地下水补给影响下的河流水质模糊模拟

基于河流水环境系统的模糊性、不精确性,采用三角模糊数描述和表征沿岸地下水水文地质参数,建立了计算地下水补给量和补给强度的模糊模型。并进一步在三角模糊数的基础上,构建了考虑地下水补给影响的一维稳态河流水质模糊模拟模型。将该模型应用于淮河流域某支流的水质模拟研究。计算中采用α-截集技术,得到了各控制断面模糊数形式的污染物浓度值,并将其与确定性模型计算结果进行对比分析。分析结果表明,以三角模糊数原理模拟和表征考虑地下水补给影响的河流水体污染物浓度变化规律在理论上可行,其计算结果可信。     

Model-based knowledge acquisition in environmental decision support system for wastewater integrated management

The main goal of the Water Framework Directive is to achieve good chemical and ecological status of water bodies by 2015. The implementation of integrated river basin management, including sewer systems, wastewater treatment plants and receiving water bodies, is essential to accomplishing this objective. Integrated management is complex and therefore the implementation of control systems and the development of decision support systems are needed to facilitate the work of urban wastewater system (UWS) managers. Within this context, the objective of this paper is to apply integrated modelling of an UWS to simulate and analyse the behaviour of the 'Congost' UWS in Spain, and to optimize its performance against different types of perturbations. This analysis results in optimal operating set-points for each perturbation, improves river water quality, minimizes combined sewer overflows and optimizes flow lamination from storm water tanks. This is achieved by running Monte Carlo simulations and applying global sensitivity analysis. The set-points will become part of the knowledge base composed of a set of IF-THEN rules of the environmental decision support system being developed for this case study.     

An integrated modelling concept for immission-based management of sewer system, wastewater treatment plant and river.

Today's planning standards deal with the individual urban drainage components (sewer system, wastewater treatment plant and receiving water) separately, i.e. they are often designed and operated as single components. As opposed to this, an integral handling considers the drainage components jointly. This novel approach allows a holistic and more sustainable planning of urban drainage systems. This paper presents an integrated modelling concept. The aim is to analyse fluxes through the total wastewater system and to integrate pollution-based control in the upstream direction, that is, e.g., managing the combined water retention tanks as a function of state variables in the WWTP or the receiving water. All models of the different subsystems are based on the Activated Sludge Model (ASM) concept of IWA, including River Water Quality Model No. 1 (RWOM). Simulations can be done in truly parallel mode using the simulation environment SIMBA. The integrated modelling concept is applied to the river Dhuenn and the urban wastewater system of the municipality of Odenthal (Germany). An optimised operation of the system using RTC proves to be a very effective measure.     

城市河流综合整治工程的治理效果预测研究

以湖南省常德市穿紫河综合整治工程为例,利用美国环保局开发的综合水质模型QUAL2E对该工程治理方案进行效果预测。根据综合整治的主要治理措施设计了穿紫河水质模拟的五大类情景,模拟了CODCr、DO、BOD5、NH3 N等4项指标,进一步分析了不同截污程度、引水方案和引水量组合工程措施对提高水质达标率的作用,为穿紫河综合整治工程提供合理化建议。     

南京河西水系引江冲污改善水环境方案研究

针对城市河道的水环境污染日益严重的问题,采用引水冲污方式,可提高河道的水环境净化能力,有效改善城市水环境。以南京市河西水系水质现状为例,建立了一维河网水量水质模型,根据从长江引水的线路、方式及规模,利用所建立的模型,分析了南京市河西水系各河流引水冲污改善水环境的效果。分析结果表明,引水冲污能使城市河道污染浓度快速下降,有效改善城市河道水环境。     

Frequency analysis of river water quality using integrated urban wastewater models

In recent years integrated models have been developed to simulate the entire urban wastewater system, including urban drainage systems, wastewater treatment plants, and receiving waterbodies. This paper uses such an integrated urban wastewater model to analyze the frequency of receiving water quality in an urban wastewater system with the aim of assessing the overall system performance during rainfall events. The receiving water quality is represented by two indicators: event mean dissolved oxygen (DO) concentration and event mean ammonium concentration. The compliance probability of the water quality indicators satisfying a specific threshold is used to represent the system performance, and is derived using the rainfall events from a series of 10 years' rainfall data. A strong correlation between the depth of each rainfall event and the associated volume of combined sewer overflow (CSO) discharges is revealed for the case study catchment, while there is a low correlation between the intensity/duration of the rainfall event and the volume of the CSO discharges. The frequency analysis results obtained suggest that the event mean DO and ammonium concentrations have very different characteristics in terms of compliance probabilities at two discharging points for CSO and wastewater treatment plant effluent, respectively. In general, the simulation results provide an understanding of the performance of the integrated urban wastewater system and can provide useful information to support water quality management.     

Loading and lake circulation structures recurrent patterns of water quality on the Toronto – Mississauga waterfront of Lake Ontario

Urban centers line western Lake Ontario where urban rivers, wastewater treatment plants and stormwater load nutrients, major ions and suspended solids to the nearshore. In 2018, nearshore water quality and associated physical conditions bordering the cities of Toronto and Mississauga were assessed as a benchmark for future effects of urban growth and municipal infrastructure projects to improve water quality. Conductivity and UV-fluorescence were used as water quality surrogates and mapped over blocks of shoreline stratified by distance offshore. Patterns in UV-fluorescence aligned with loading points, and generally higher levels near the shoreline, were correlated with concentrations of nutrients, major ions and suspended solids. Water quality was more land-impacted over the shoreline from the Credit River to Humber Bay contrasting with the more lake-like conditions from Toronto Eastern Beaches to the Rouge River. Within Toronto Harbour, cross-harbour gradients in water quality varied with weather-related changes in river and storm water loading. Mixing areas at wastewater treatment plant outfalls and tributary mouths, frequently shaped by alongshore lake circulation, resulted in a mosaic of water quality over the shoreline. Area-wide elevation of chloride and conductivity, and poorer water quality in late spring, was linked to heightened river discharge. Thermal stratification affected how discharges were distributed in the water column, but measurements at the lake surface reflected the strongest overall land-effects on water quality. The patterns of temporal-spatial variability identified within geographically-defined areas of shoreline can be used as past footprints in future monitoring to detect change.     

Water Quality Assessment of the Santiago River and Attenuation Capacity of Pollutants Downstream Guadalajara City,Mexico

The Santiago River in Mexico has been seriously polluted because of rapid urbanization and industrialization activities, lacking of appropriate planning and contamination monitoring policies. This research characterized the river water quality and recognizes some overall pollution sources, using two different information references: a dataset of 5 years from the Jalisco State Water Commission and a 14‐year dataset from the National Water Commission. Two zones have been identified as the main sources of pollution (hotspots), where the major events of urban and industrial wastewater discharges occur: (i) the urban fringe of Guadalajara city, with special emphasis in its southern area (nearby the so‐called El Ahogado stream) and (ii) downstream of Guadalajara City. Nevertheless, we have recognized some areas along the Santiago River where significant reduction of pollutants concentration takes place, possibly due to dilution by the inflow of tributaries and to the rainfall increasing. In addition, it is likely that hydropower dams are positively influencing the retention of pollutants along the river. In the lower zone, the water concentrations of O₂ are consistently above acceptable levels (up to 5 mg L^?1), and the majority of the pollution indicators parameters are below the maximum permissible values, despite the high pollution in Guadalajara area. This paper attempts to offer a methodological approach for a more accurate assessment of the river water quality and may assist in interpreting the sampling results derived from the regular monitoring, conducted by the state water authorities, while emphasizing the natural attenuation capacity of the Santiago River. Copyright © 2015 John Wiley & Sons, Ltd.     

大汶河污染现状及其治理措施

阐述大汶河污染对南水北调东线工程水质的危害 ,分析大汶河主要的污染来源。为实现大汶河水质控制目标 ,必须从管理措施和工程措施两方面着手 ,即提高认识 ,深化改革 ,以法治污 ;从末端治理转为源头治理 ;建设好污水处理厂 ,集中处理城市污水 ;治理河道污泥 ;发展生态农业 ,治理面源污染 ;划定大汶河水生态环境保护区。     

辽河流域河流水质综合评价

本文以辽河流域为例,将水质风险次序权重与组合准则权重相耦合构建评价模型,运用该模型计算评价了多种次序权重和河流水质等级。结果表明:风险水平α=1的条件下,国标法划分的监测点水质类别与该方法保持较好的一致性,对于河流水质的评价该方法符合实用性和可行性要求;石油类、总磷、氨氮、总有机碳等因子对流域水质的影响显著;入海口水质受地理位置制约,总体处于较差水平;水环境污染来源以工业废水、城市和农业污水为主。该耦合评价方法可为流域水环境保护和水质治理提供数据支撑。