污水再生利用微生物控制标准及其制定方法探讨

污水再生利用的关键是水质安全保障和风险控制.微生物风险是再生水安全利用过程中需要优先控制的重要问题.本文系统探讨了我国现行污水再生利用标准中的病原微生物控制要求,分析了基于病原微生物指示指标浓度控制的必要性与不足,提出了引入微生物去除能力保障控制的必要性,并详细介绍了其制定方法与保障措施.今后,需进一步深入探讨基于浓度控制与保障能力控制相结合的污水再生利用微生物控制方法,以期为我国再生水安全利用提供技术支撑.     

城市污水再生回用于景观水体水质安全保障技术

研究了再生水回用于景观水体时可能存在的水质安全性问题,并提出了保障再生水安全回用的处理工艺。研究表明,城市污水再生水回用于景观水体时,存在着卫生学安全、毒理学安全、富营养化以及底质二次污染等危害。为了满足景观水体的水质标准,需要重点控制的水质指标有病原性微生物、有毒有害有机物、重金属、氮磷植物性营养物质、悬浮固体。以城市污水厂二级出水作为再生水原水时,推荐采用的工艺有:二级处理混凝沉淀过滤消毒、二级处理过滤活性炭吸附消毒以及二级处理膜处理消毒工艺。     

城市再生水厂出水中典型有机污染物的赋存情况及其生态风险评价

由于再生水中含有微量或者痕量的有机污染物,因此再生水利用过程中潜在的生态和健康风险一直受到社会的广泛关注.为探明再生水中多环芳烃（PAHs）、邻苯二甲酸酯（PAEs）和农药等典型有机污染物的赋存情况以及其在再生水厂提标改造前后的去除情况,本文于2019年对北京市5座再生水厂出水进行了连续6个月的监测,并对检出的PAHs、PAEs和农药进行了生态风险评价.结果显示：5座再生水厂出水中检出率为100%的污染物为PAHs中萘（NaP）、芴（Flu）、菲（Phe）、蒽（Ant）、荧蒽（Flua）、芘（Pyr）、苯并[a]蒽（BaA）、（Chr）、苯并[a]芘（BaP）,PAEs中邻苯二甲酸二甲酯（DMP）、邻苯二甲酸二乙酯（DEP）、邻苯二甲酸二异丁酯（DIBP）、邻苯二甲酸二正丁酯（DNBP）、邻苯二甲酸二乙基己酯（DEHP）和农药中敌敌畏、阿特拉津.在各类污染物的组分分布上,总PAHs含量中以2、3环的PAHs为主,主要包括Phe、NaP、Flu、Ant和Ace,共占PAHs总量的55%以上;PAEs中以DEHP、DMP、DIBP和DNBP为主,共占总PAEs含量的80%以上;农药中以敌敌畏和阿特拉津为主.5座再生水厂出水中总PAHs的月平均浓度为53.6~65.9 ng·L^-1;总PAEs的月平均浓度为4881.3~7050.2 ng·L^-1;总农药的月平均浓度为77.7~97.2 ng·L^-1.与污水处理厂改造前相比,出水中PAHs和PAEs的总浓度明显下降,其中PAHs总浓度下降约一个数量级;农药中有机氯农药在改造前文献报道有检出,而改造后我们的样品中均为未检出;通过对检出目标化合物的生态风险评价,所有PAHs,PAEs中DMP、DEHP、DEP,农药中阿特拉津和百菌清在各水厂出水中均为低风险污染物,但是PAEs中DIBP和DNBP在各水厂出水中均为中、高风险污染物;农药敌敌畏和毒死蜱在个别月份样品中表现出了中风险.     

Bioassay: A useful tool for evaluating reclaimed water safety

Wastewater reclamation and reuse has been proved to be an effective way to relieve the fresh water crisis. However, toxic contaminants remaining in reclaimed water could lead to potential risk for reuse, and the conventional water quality standards have difficulty guaranteeing the safety of reclaimed water. Bioassays can vividly reflect the integrated biological effects of multiple toxic substances in water as a whole, and could be a powerful tool for evaluating the safety of reclaimed water. Therefore, in this study, the advantages and disadvantages of using bioassays for evaluating the safety of reclaimed water were compared with those of conventional water quality standards. Although bioassays have been widely used to describe the toxic effects of reclaimed water and treatment efficiency of reclamation techniques, a single bioassay cannot reflect the complex toxicity of reclaimed water, and a battery of bioassays involving multiple biological effects or in vitro tests with specific toxicity mechanisms would be recommended. Furthermore, in order to evaluate the safety of reclaimed water based on bioassay results, various methods including potential toxicology, the toxicity unit classification system, and a potential eco-toxic effects probe are summarized as well. Especially, some integrated ranking methods based on a bioassay battery involving multiple toxicity effects are recommended as useful tools for evaluating the safety of reclaimed water, which will benefit the promotion and guarantee the rapid development of the reclamation and reuse of wastewater.     

沈阳市中水回用对策研究及前景分析

为了解决全市水资源严重短缺问题，缓解污水排放对生态环境造成的破坏，沈阳市在今后5～10a内将建成中水回用系统，使城市中水回用率达到50％。结合沈阳市中水回用现状，分析了目前全市中水供应能力及市场需求，进行了2010年相应指标的预测，同时探讨了沈阳市中水回用存在的问题和解决方法。     

A toxicity-based method for evaluating safety of reclaimed water for environmental reuses

A large quantity of toxic chemical pollutants possibly remains in reclaimed water due to the limited removal efficiency in traditional reclamation processes. It is not enough to guarantee the safety of reclaimed water using conventional water quality criteria. An integrated assessment method based on toxicity test is necessary to vividly depict the safety of reclaimed water for reuse. A toxicity test battery consisting of lethality, genotoxicity and endocrine disrupting effect was designed to screen the multiple biological effects of residual toxic chemicals in reclaimed water. The toxicity results of reclaimed water were converted into the equivalent concentrations of the corresponding positive reference substances（EQC）. Simultaneously, the predicted no-effect concentration（PNEC） of each positive reference substance was obtained by analyzing the species sensitivity distribution（SSD） of toxicity data. An index ＂toxicity score＂ was proposed and valued as 1, 2, 3, or 4 depending on the ratio of the corresponding EQC to PNEC. For vividly ranking the safety of reclaimed water, an integrated assessment index ＂toxicity rank＂ was proposed, which was classified into A, B, C, or D rank with A being the safest. The proposed method was proved to be effective in evaluating reclaimed water samples in case studies.     

Wastewater reclamation and reuse in China: Opportunities and challenges

The growing water stress both in terms of water scarcity and quality deterioration promotes the development of reclaimed water as a new water resource use. This paper reviewed wastewater reuse practices in China, and the opportunities and challenges of expanding reclaimed water use were analyzed. Rapid urbanization with the increasing of water demand and wastewater discharge provides an opportunity for wastewater reuse. The vast amount of wastewater discharge and low reclaimed water production mean that wastewater reuse still has a great potential in China. Many environmental and economic benefits and successful reclamation technologies also provide opportunities for wastewater reuse. In addition, the overall strategy in China is also encouraging for wastewater reuse. In the beginning stage of wastewater reclamation and reuse, there are many significant challenges to expand wastewater reuse in China including slow pace in adopting urban wastewater reuse programs, the establishment of integrated water resources management framework and guidelines for wastewater reuse programs, incoherent water quality requirements, the limited commercial development of reclaimed water and the strengthening of public awareness and cooperation among stakeholders.     

北京市清水与再生水协同利用优化模型

开展协同利用清水与再生水的城市供水系统优化研究具有重要的科学意义和广阔的应用前景.为促进城市水资源高效利用,基于多水源转换关系以及再生水生产能力和利用潜力,构建了面向多区域多部门的城市清水与再生水协同利用优化模型,并以水资源严重短缺的北京市为例进行实证研究.设置规划方案基准情景和规划替代方案情景,分别优化了清水与再生水的协同利用方案以及再生水厂群的运行方案.在规划方案基准情景下,再生水占研究区用水总量的32%,分别占农业、工业、环境用水量的60%、30%和42%.海淀区和石景山区再生水供给矛盾将较为突出.相比之下,规划替代方案情景可以获得更高的经济效益,总效益增加6. 21亿元,同时能增加再生水利用量36. 59%、减少清水用量14. 02%.规划替代方案能更加充分地利用现有设施,促进水资源循环利用.此外,还提供了在现有设施条件下,再生水利用量由政策规划值逐渐提升至最佳规模过程中再生水厂群的运行过渡方案.本文建立的研究方法具有较广泛的适用性,可用于解决其它具有再生水利用潜力地区的水资源短缺问题.     

区域水资源介循环利用模式:概念·结构·特征

为解决我国面临的突出水环境问题,破解经济发展需求与水资源短缺、水环境污染和水生态破坏之间的矛盾,提出区域水资源“介循环”(water meta-cycle)利用模式,系统地阐述了区域水资源介循环利用模式的结构特征、基本特点和目标定位,并通过案例分析了其适用效果. 介循环是一种人工强化生态调控的区域水资源多阶多元循环利用模式. 通过企业、家庭和社区等局部单元内的水循环利用,工业和城市等社会系统尺度内的污水再生处理与直接利用,以及区域层面上再生水的生态媒介循环利用(water natural system-mediated reuse)等,促进不同层阶和不同用途水循环利用的有机衔接与耦合,实现再生水的安全聪巧(safe and smart)利用、区域尺度上水资源的闭环循环利用和趋零排放. 区域水资源介循环利用模式以再生水的生态媒介循环利用为核心,具有闭环趋零、多阶多元、强化调控和复合高效等特点,有望成为区域水资源可持续管理、保障水环境安全的有效模式.      

臭氧化-生物活性炭净化水厂的运行效能

吉林省前郭炼油厂生产区及其居民区的优质饮用水净化水厂采用臭氧化 生物活性炭工艺处理传统水处理厂的滤后水。传统水处理厂由混凝、絮凝、沉淀和快速过滤组成。该饮用水深度净化厂运行性能稳定,最后出水完全达到国家饮用水水质标准。GC/MS分析结果表明,最后出水中含有5种微量有机污染物,不含重点及潜在的有害的微量有机污染物,而传统水处理厂的滤后水含有115种微量有机污染物,5种重点有害污染物和23种潜在的有害有机污染物     

再生水中优先控制有毒污染物的筛查方法

建立了一种适用于再生水中优先控制有毒有机污染物筛查的方法.针对样品前处理方法中的固相萃取柱的选择和洗脱剂条件等进行了优化设计,利用保留时间锁定和谱图解卷积技术分辨复杂系统中的目标污染物,并利用有毒化合物数据库进行有毒污染物甄别.结果表明,采用C18柱串联HLB柱的方法进行富集,用1:1(V/V)的正己烷/二氯甲烷混合溶剂和4:1(V/V)的二氯甲烷/甲醇混合溶剂进行分级洗脱的前处理方法,对分配系数(logKow)在1.48~6.41之间的30种化合物平均回收率在52.1%~138%之间,相对标准偏差值均<13.6%.将该方法应用于天津空港地区再生水中有毒有机污染物的筛查,2007~2008年度2次采集样品分别筛查出30种有毒有机污染物,其中有7种属于《城镇污水处理厂污染物排放标准》中已列入监管范围的污染物,11种未列入排放标准监测范围.比较污水处理厂进、出水以及地表水中检出污染物,发现现有污水处理工艺对筛查出的优先有机污染物处理效果不佳.     

浅层气浮处理微污染水体机理研究

采用中水作为小区封闭景观水体的原水和补充水,针对景观水体受污染的特点,构建一种结合生物与气浮技术优点的处理方法,重点分析影响其处理效果的各种因素,建立包含一个主流程和两个内部循环的BOAF高效浅层气浮净化处理装置系统。实验结果表明,BOAF浅层气浮技术用于处理微污染水体是可行的,为中水景观水体的应用和推广提供了坚实的技术保障。     

城市自来水光催化氧化深度净化效果

在玻璃纤维网上制得ＴｉＯ２催化膜．用相应的固定膜光催化氧化装置进行了城市自来水的深度净化研究．ＧＣ／ＭＳ分析表明，在水中输入能量８７Ｗ／Ｌ的低光照强度下，经１ｈ的处理，自来水中有机物总量去除率在６０％以上．１９种优先污染物有５种消失，另２１种有害物质中１０种浓度降至仪器检测限以下．与此同时，水中各种有机物的浓度均显著下降．中间产物中基本不含有害的物质．光催化氧化对城市自来水中有机污染物有令人满意的去除效果．     

A biological safety evaluation on reclaimed water reused as scenic water using a bioassay battery

An assessment method based on three toxicity tests (algae growth inhibition, daphnia immobilization and larval fish toxicity) was used to screen the biological safety of reclaimed water which was reused as sole replenishment for scenic water system in a park (SOF Park) in northern China. A total of 24 water samples were collected from six sites of water system in the SOF Park in four different seasons. The results indicated that: (1) the reclaimed water directly discharged from a reclamation treatment plant near the SOF Park as influent of park had relatively low biological safety (all samples were ranked as C or D); (2) the biological safety of reclaimed water was improved greatly with the ecological reclamation treatment processes composing of artificial wetland system and followed oxidation pond system; (3) the biological safety of reclaimed water in the main lake of SOF Park kept at a health status during different seasons (all samples were ranked as A); (4) there was some certain correlation (R² = 0.5737) between the sum of toxicity scores and dissolved organic carbon for the studied water samples. It was concluded that the assessment method was reliable to screen the safety of reclaimed water reused as scenic water, and the reclaimed water with further ecological purification processes such as artificial wetland and oxidation pond system can be safely reused as scenic water in park.     

城市污水中新兴微量有机污染物控制目标与再生处理技术

城市污水再生利用是缓解城市缺水问题和改善城市水环境质量的重要方法,其前提是水质安全保障.城市污水中近年来不断检出新兴微量有机污染物（trace organic contaminants,TOrCs）,如抗生素、全氟化合物、雌激素等,是再生水水质安全的重要威胁.针对城市污水再生深度处理需明确新兴TOrCs控制目标和处理技术的需求,系统比较了欧盟、美国、澳大利亚等再生水利用先行国家和地区在TOrCs控制目标、指南、规范、技术与工艺管理等方面的研究和实践进展.结果表明,由于TOrCs浓度低且种类多,TOrCs被分为高风险TOrCs和指示性TOrCs.美国加州地区和澳大利亚根据风险水平和检出水平分别提出了高风险TOrCs和指示性TOrCs种类清单和浓度限值,然而该清单中的TOrCs种类和浓度限值尚未列入强制标准或规范.针对再生水TOrCs风险控制需求,瑞士、美国加州等提出了多级屏障再生水处理工艺.瑞士提出,城市污水深度处理对卡马西平等药品类TOrCs去除率应大于80%,美国加州规定补充饮用水源的再生水深度处理应去除69%以上的1,4-二恶烷.此外,TOrCs控制高度依赖重源头控污（工业废水阻断）、单元协同、在线监控反馈与实时优化等全流程安全保障措施.随着我国再生水用量持续增加,用途不断拓展,亟需制定针对性强、现实可行的TOrCs控制指南和规范,包括明确高风险和指示性TOrCs,推动多级屏障再生水深度处理工艺,以TOrCs去除率为深度处理目标.      

Removal of fluorescence and ultraviolet absorbance of dissolved organic matter in reclaimed water by solar light

Storing reclaimed water in lakes is a widely used method of accommodating changes in the consumption of reclaimed water during wastewater reclamation and reuse. Solar light serves as an important function in degrading pollutants during storage, and its effect on dissolved organic matter(DOM) was investigated in this study. Solar light significantly decreased the UV_(254) absorbance and fluorescence(FLU) intensity of reclaimed water.However, its effect on the dissolved organic carbon(DOC) value of reclaimed water was very limited. The decrease in the UV_(254) absorbance intensity and FLU excitation–emission matrix regional integration volume(FLU volume) of reclaimed water during solar light irradiation was fit with pseudo-first order reaction kinetics. The decrease of UV_(254) absorbance was much slower than that of the FLU volume. Ultraviolet light in solar light had a key role in decreasing the UV_(254) absorbance and FLU intensity during solar light irradiation. The light fluence-based removal kinetic constants of the UV_(254) and FLU intensity were independent of light intensity. The peaks of the UV_(254) absorbance and FLU intensity with an apparent molecular weight(AMW) of 100 Da to 2000 Da decreased after solar irradiation, whereas the DOC value of the major peaks did not significantly change.     

开阔海域围填海规划的水质影响评价方法——以福建省湾外围填海为例

基于开阔海域围填海的特殊性,已有的水质影响评价定量方法较难直接应用。本文通过水动力因子分析确定污染物扩散条件,根据水质现状、围填面积和规划利用方式确定水质压力。基于上述污染物扩散条件和水质压力参数,以水质影响程度等级作为评价结果,设计了半定量评价矩阵对福建省湾外围填海规划的10个围填区进行了水质影响评价。评价结果表明:其中有1个围填区水质影响程度较大,其余围填区水质影响程度均在中等以下。此外,水质影响程度评价结果可同时为湾外围填海规划决策者提供相应的决策依据。案例应用表明:该半定量方法可以推广应用于决策型的、影响机制复杂、不确定性较强的人类活动的水质影响评价。     

沈阳市典型城市河流优先控制污染物筛选及生态环境风险评估

细河和蒲河接纳了沈阳市工业废水的排放,水体中有毒、有害污染物不容忽视.为了明确河流中优先控制污染物,评价实际暴露水平下优先控制污染物对该水系生态环境的风险,选择细河和蒲河表层水为研究对象,开展了平水期、丰水期和枯水期的采样及有机污染物的检测分析;通过改进的潜在危害指数法对水体中检出的52种有机污染物打分排序,筛选了优先控制污染物;将效应评价外推法与商值法结合评价了优先控制污染物的生态环境风险.结果表明:52种有机污染物在细河中检出的平均质量浓度范围为9.20×10-6~1.37×10-1 mg/L,在蒲河中检出的平均质量浓度范围为4.30×10-6~3.03×10-2 mg/L.细河或蒲河中这些污染物的危害指数总分值（R）在22分以上的分别有12和13种,其中,PAEs（酞酸酯类）占6种,苯酚类污染物占4种.在细河中,DBP（邻苯二甲酸二丁酯）、苯酚、对甲基苯酚、2,4-二甲基苯酚和2,4,6-三甲基苯酚的R_q（风险商）>1,表明这些污染物存在较大的生态环境风险;在蒲河中,DBP、DEHP[邻苯二甲酸二（2-乙基己基）酯]和苯酚的R_q>1,表明这些污染物存在较高生态环境风险水平.研究显示,在细河、蒲河中PAEs和苯酚类有机物为优先控制污染物,其中部分优先控制污染物具有较高的生态环境风险,可为该流域有毒、有害物污染控制方案的制定提供参考和指导.      

京津冀及周边地区优先控制有毒有害大气污染物名录研究

近年来,随着污染防治攻坚战的不断强化,京津冀及周边地区重污染天气问题初步得到缓解.为了深度改善大气环境质量,落实精准治污,更好地服务于京津冀有毒有毒大气污染物的环境管理,开展了京津冀及周边地区优先控制有毒有害大气污染物名录的研究.以京津冀及周边地区为主要研究对象,采用文献调研法建立备选名单;针对备选名单中的有毒有害大气污染物进行危害信息收集,采用两步筛选法,以危害筛选指标、暴露筛选指标、持久性/生物蓄积性筛选指标共包含10项内容进行赋分求和,筛选出高分值的污染物建立候选名单;在候选名单基础上,从国家排放标准、地方排放标准、监测方法三方面进行筛选,形成优控名录.筛选形成的优控名录包括苯、环氧乙烷、二英类、砷及其化合物、铅及其化合物、甲醛、氯乙烯、三氯乙烯、1,2-二氯丙烷、氯甲基甲醚、铍及其化合物、三氯甲烷在内的12种（类）污染物,可为“十四五”有毒有害大气污染物环境管理及今后京津冀优控名录的公布提供研究基础.      

不同干扰强度对滩涂围垦区土壤颗粒组成的时空分异特征的影响

滩涂是陆地与海洋间重要的生态交错带以及生态系统之一,随着沿海地区经济的发展,滩涂围垦成为缓解区域土地利用压力的重要途径之一。论文通过对不同围垦年限以及不同人类干扰强度下土壤粒径分布（Particle Size Distribution）的时空差异研究,比较了自然演变和人类活动双重影响下,垦区环境的变化过程及影响因素。结果表明：1）在60 a的围垦过程中,在强烈、中度和无人类干扰强度下,土壤粒径分布均表现出在脱盐过程中随围垦年限增加而砂粒减少、粉粒和粘粒增加的过程,脱盐后砂粒的年均下降率可达0.72%;2）在无干扰强度下,土壤粒径分布反映出滩涂围垦和脱离海水影响的自然过程,而强烈和中度干扰强度则在此基础上反映出人为和自然干扰的综合效果;3）耕种方式、时间以及土壤侵蚀等因素均会对土壤粒径分布的变化强度造成影响而表现出显著的空间差异性;4）土壤粒径的时空分布可以综合反映出滩涂围垦区的环境特点,对指导垦区内土地资源的合理开发利用具有重要意义。在长期的围垦过程中,不同的开发利用时间及区位表现出了不同的关键影响因素,使垦区内土地利用格局和资源配置仍存在诸多不合理之处,随之带来相应的环境问题必须引起重视,为未来滩涂围垦区的合理规划提供理论依据。