笔架山水厂水处理效果及其健康风险初步评价

对采用O3—BAC深度处理工艺的笔架山水厂运行效果进行了试验研究,建立了饮用水健康风险评价模型并对水厂原水和出厂水进行了饮水途径的健康风险评价。研究结果表明:笔架山水厂水处理效果较好,可以有效去除感官性状、浊度物质以及有机物,使微生物监测指标均达到了相应标准的要求,对浮游动物的平均去除率可达92.71%;健康风险评价结果显示,经过O3—BAC工艺处理后,饮用水通过饮水途径所致个人健康危害风险明显降低,致癌物Cr(Ⅵ)所产生的健康风险数量级为10-4,非致癌物产生的健康风险数量级为10-11～10-9。     

污水再生处理过程中病原性原虫的去除特性研究

隐孢子虫和贾第鞭毛虫(简称“两虫”)是两种严重危害再生水水质安全的病原性原生动物。污水是病原性原虫的主要污染源,传统二级生物处理出水中的两虫浓度较高,深度处理工艺是去除两虫从而保障再生水水质安全的屏障。本文的目的是考察城市污水和再生水中两虫的污染现状,系统研究污水再生处理单元技术及典型工艺对两虫的去除特性,为客观评价污水再生利用的健康和生态风险,解决两虫污染问题提供理论依据。本研究首先针对国际上常用的两虫检测方法———1623方法中存在的成本高、回收率低等问题,对其各个环节进行系统的研究和优化,建立了适用于…     

再生水厂处理工艺对邻苯二甲酸酯去除效果分析

以北京城区4座不同处理工艺的再生水厂进出水为研究对象,采用固相萃取(SPE)预处理和气相色谱-质谱法(GC-MS)方法对再生水标准中涉及到的邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二(2-乙基己基)酯(DEHP)两类污染物进行了检测,对比分析不同再生水处理工艺的去除效果。结果表明,各水厂进水中DBP和DEHP的浓度范围分别为1.99～5.36μg/L和0.97～6.44μg/L,与上游污水处理厂所采用的处理工艺无明显关联性;出水中DBP浓度为1.74～5.59μg/L,DEHP浓度范围0.42～4.93μg/L,均低于景观环境用水的国家标准限值;常规混凝-过滤-消毒处理工艺的去除效果并不明显,而膜工艺由于膜污染等实际运行问题也没有达到理想去除效果,去除率不足60%。     

随机分析方法在污水回用风险评价中的应用

随着城市污水回用工程增多,再生回用水的安全性问题日益受到人们的重视,回用水中病原微生物对人体的健康风险是焦点问题之一.对再生水回用造成的人体健康风险评价方法进行了讨论,通过实例介绍了随机分析方法在健康风险评价中的应用.     

污水再生利用——收益和风险

城市污水再生利用是对水资源重复利用的有效途径,具有显著的经济效益和深远的社会效益。然而,城市污水往往含有一些有害成分,会造成一系列环境问题和人类健康问题。此外,城市再生水用于农业灌溉会产生负面影响,因此再生水用于农业灌溉也成为了人们主要关注的焦点。本文讨论城市污水再生利用的收益,并重点阐述了当前再生水利用问题和风险。     

天津市中心城区再生水利用现状及工艺运行总结

根据天津城市污水再生利用的背景,介绍了天津市中心城区再生水利用现状,分析了目前再生水利用情况,着重总结了天津市污水再生利用处理工艺的选择原则和工艺运行特点。     

净水工艺对多环芳烃和卤代烷烃类污染物去除效果分析

研究了中试中3种不同处理工艺及丹江口市某净水厂对丹江口水源水中多环芳烃和卤代烷烃类污染物的去除效果,并评价了不同处理工艺段出水中该类污染物浓度水平,以及出厂水对不同季节、不同消费习惯人群的致癌风险。结果表明,混凝沉淀可以去除大多数有机有毒污染物,后续的过滤过程能进一步加强有机有毒污染物的去除效果。出水中残留的多环芳烃和卤代烷烃类污染物对北京市人群的总致癌风险处于10-7～10-6水平,健康风险处于很低水平。     

再生水用于绿化灌溉的健康风险评价研究

以北京市某再生水利用工程为例,用健康风险评价的方法,对再生水用于公园绿化灌溉时接触人群的暴露水平和健康风险进行了系统研究,建立了再生水用于公园绿化灌溉的健康风险评价模型,提出了再生水对职业人员和公众的暴露参数,对再生水中氯仿等19种主要污染物的健康风险进行了定量评价.结果表明:职业人群致癌的总危险度为3.91×10-6;非职业人群致癌的总危险度中青年和老年分别为2.12×10-6、1. 27×10-6,均小于可接受健康危险水平10.     

城市再生水利用风险评价指标体系初探

水的再生利用是破解我国水资源短缺问题的重要途径之一,但是再生水利用对人体健康和环境的影响也是生活污水处理必须面对的挑战,从而受到人们普遍关注。根据我国再生水回用途径和天津市纪庄子再生水厂的出水水质情况,构建了再生水利用风险评价指标体系(包括健康风险指标和生态环境风险指标),并对纪庄子再生水厂的出水与景观用水和地表水分别进行了风险评价,得出再生水用在不同用途时存在的不同环境风险。     

再生水回用现状及展望

水资源短缺是制约中国经济发展的主要障碍，再生水回用是解决该问题的有效途径，亟需明确中国再生水行业发展现状与现存问题，以实现城市生态化与可持续发展。研究综述了中国再生水回用的政策、法规和标准，总结了国内外再生水回用的主要途径，介绍了再生水处理技术发展现状和应用实例，并对未来发展进行展望。综上，针对中国再生水回用提出4点建议：(1)健全再生水回用标准规范；(2)加强污水处理厂再生水处理工艺改造；(3)建立再生水风险评价体系；(4)增加城市再生水回用建设规划。     

利用小型污水处理设施和中水解决城镇水资源问题

水资源短缺和水环境污染已经成为城市和小城镇可持续发展的制约因素，中水回用则是解决这两个问题的重要举措。在调查分析了石家庄市水资源、污水处理和中水回用情况的基础上，回顾了污水处理和中水回用的发展历程，分析了中水回用的不同方法，以石家庄为例进行中水回用的经济效益分析。分析表明大力推行小型污水处理设施并进行中水回用是城市和小城镇水资源可持续发展的重要举措。     

再生水回灌浅层地下水水质变化实例分析

在分析国内外再生水回灌地下水研究现状及存在问题基础上,以高碑店污水处理厂再生水回灌试验场为例,采用三维荧光光谱等分析方法,分析再生水进入含水层后污染物运移变化规律及水质变化情况,分析再生水回灌浅层地下水的可行性,以及回灌地层对于再生水水质中有机物和无机物的净化和去除作用。同时通过使用发光细菌,评价了再生水回灌地下水的污染风险,对城市再生水的综合无害化利用提出建议。     

浅谈再生污水地下回灌的健康危害风险

针对目前污水再生利用越来越广泛的现状,探讨了再生污水的健康危害风险评价方法,分析了非饮用回用及饮用回用时要注意的问题和对策。并对北京高碑店污水处理厂二级生化出水经深度处理地下回灌后用作饮用回用的健康危害风险进行了实例分析评价。     

再生水的卫生安全问题探讨

阐述了污水和再生水中的病原微生物 ,介绍了国内外再生水卫生学控制指标及标准 ,再生水卫生安全评价方法、评价模型及评价实例 ,认为再生水经适宜的工艺处理和消毒后 ,可以使水质和病原微生物降低至安全使用水平。提出再生水卫生安全的重要性及加强调查研究和基础跟踪研究的必要性。     

Integrated Management of Non-conventional Water Resources in Anhydrous Islands

Anhydrous islands are dependent either on non-conventional water resources, such as desalinated seawater or reclaimed water from wastewater, or on water importation from the mainland. The latter option is often expensive and non-sustainable. Desalinated water can be used for potable and non-potable water applications, while reclaimed water can be used for non-potable water applications. Thus all water needs can be satisfied by an optimal blend of desalinated and reclaimed water. It is important to calculate the optimal capacities and locations of seawater desalination plants, wastewater treatment plants and water reclamation plants, and to estimate the water/wastewater conveyance system, in order to minimise water production and distribution costs. Mathematical modelling and optimisation techniques can be employed for calculating the optimum scenario: the satisfaction of all water needs at minimum cost. In this article, we have estimated the water demands taking into account water quality for the anhydrous Greek island of Syros, in the Aegean Sea. Syros has been subdivided into 6 regions, taking into account geographical and population distribution criteria. All water needs are to be satisfied by desalinated seawater and reclaimed water. A mixed-integer linear programming algorithm is used here to calculate the optimal scenario (location and capacities of desalination plants and wastewater treatment and water reclamation plants, as well as the desalinated water, reclaimed water and wastewater conveyance infrastructure needed) by minimising the annualised total cost including capital and operating costs.     

Viability of increasing the tariff of freshwater for irrigation as a tool to stimulate wastewater reuse in the MENA region.

Despite water scarcity and high agricultural water demand in the Middle East and North Africa region, substantial proportions of treated wastewater are discharged into the environment and seas without proper utilization. All countries of the region, low pricing of reclaimed wastewater is a common tool to make reuse attractive. However, low pricing of reclaimed wastewater is ineffectual due to farmers' access to freshwater for irrigation at low tariff. Therefore, increasing the prices of freshwater in such a way that does not jeopardize feasibility of agriculture would promote irrigation with reclaimed wastewater even at increased prices. On one hand, it increases the gap between the price of freshwater and that of reclaimed wastewater, making the later more attractive. On the other hand, it would be used as a financial resource for funding the investment costs of the infrastructure needed for conveyance and distribution of reclaimed wastewater. This paper studies the viability of increasing the prices of freshwater and reclaimed wastewater. The results show that irrigation with reclaimed wastewater even for restricted irrigation can be as profitable as, and sometimes better than, freshwater irrigation. Some of the permitted crops such as fruit trees can be more profitable than vegetables. Thus, it appears that the level of knowledge farmers and others on the benefits of reclaimed wastewater is still limited.     

Development of a new process for treatment of a pharmaceutical wastewater

In this study a process for biological treatment of toxic wastewater from a pharmaceutical company was developed. By simulations on a laboratory scale, the contribution of organic material and toxicity in wastewater from different sources was determined and the degradability of specific compounds were studied. The information obtained from these tests was used to improve the treatability of the wastewater at the sources. As an example a persistent organic phosphorous compound could be degraded after pre-treatment with chemical hydrolysis. By further simulations on a laboratory scale it was possible to screen through a large number of process configurations to determine the best working biological treatment A combination of fungal and bacterial treatment was found to remove toxicity from the wastewater more than a conventional bacterial treatment. The results from the laboratory studies were confirmed in pilot tests. A full scale treatment plant, which design is based on the results from these studies are presently under construction.     

Helminth eggs removal by microscreening for water reclamation and reuse.

Irrigation with reclaimed water is becoming a practical alternative to conventional irrigation in semi-arid areas of the Mediterranean like Spain, but it requires a reliable treatment process to provide a safe water supply. Helminth eggs are one of the main concerns for the safe use of reclaimed water, as they can survive adverse environmental conditions and they are highly infective. Spanish water quality criteria and International guidelines set a limit of 0.1 eggs/l for water uses with unrestricted human exposure. Two microscreening processes have been tested to determine their potential for helminth eggs removal, after a conventional physic-chemical reclamation process. Hydrotech Drum and Discfilters, provided with 10 microm pore size filter cloth, were tested to determine their efficiency for helminth eggs straining. An experimental test was conducted using 20 microm spherical latex particles, as surrogates for helminth eggs, to test the removal efficiency of a small full-scale drumfilter. In a subsequent laboratory test, actual Trichuris suis eggs were strained using a 10 microm pore size filter cloth from a discfilter. Results from both tests indicate that drum and discfilters are able to achieve 99% removal efficiency for spherical latex particles and a complete removal for helminth eggs in reclaimed water.     

MBR处理工艺主要设备选型及常见问题探讨

随着城市对再生水利用量的需求加大,提高污水处理厂出水水质已成为必然趋势。在用地有限的条件下,MBR工艺在污水处理厂新建及升级改造工程中广泛应用。介绍了MBR工艺的类型及其主要配套设备,重点针对配套设备的结构型式及其在运行中出现的常见问题进行分析,并针对设备选型提出建议。