生物活性炭去除微囊藻毒素的研究

采用生物活性炭(BAC)工艺去除饮用水中微囊藻毒素(MC)，HRT为1，5h时对CODMn和UV254的去除率分别为55．3％和35.1％，对MC—RR、MC—YR和MC—LR的去除率分别为60．57％、63．30％和68．79％。原水中较高浓度的易生物降解有机物会抑制BAC对MC的去除，大部分MC可通过微生物降解去除(同时使活性炭得到一定程度的再生)，部分MC通过吸附作用被去除。     

混凝对微囊藻毒素的去除效果及机理研究

采用静态试验研究了混凝工艺对水源水中的细胞内和溶解性（细胞外）微囊藻毒素的去除效果，并初步探讨了其去除机理。试验结果表明，混凝剂投加量为25mg／L时，将原水pH值调节到5．5～6．0可有效地去除水中的细胞内微囊藻毒素，去除率可达97．4％；投加10mg／L的粉末活性炭对致嗅物质有一定的吸附效果。强化混凝工艺可显著提高对溶解性微囊藻毒素的去除效果，对MC-RR和MC-LR的去除率均达到60％～70％，原因为强化混凝工艺强化了对小分子弱疏水性有机物的去除效果。     

电絮凝法去除二级处理出水中的磷

探讨了电解时间、电极间距、原水磷浓度、原水pH值、食盐投量等因素对电絮凝法除磷效率及能耗的影响。结果表明：电絮凝除磷反应为零级反应，曝气可提高磷去除率为10％左右，为节约能耗应将电极间距控制在1．5－2．0cm的范围内，电解6min后对磷的去除率可达70％左右，磷去除率和去除单位磷的能耗都随原水中磷浓度的增加而降低。另外，pH值＞7时对磷的去除率和能耗都影响不大，但pH值＜7时对磷的去除率大大降低；投加电解质对磷的去除率影响不大，但可大大降低能耗。     

SBR法处理城市污水的脱氮除磷功效

采用SBR工艺对广州的城市污水进行了生物脱氮除磷试验研究。结果表明：在碳、氮、磷比例不理想的情况下,达到了既去除有机物又能脱氮除磷的效果,当总停留时间控制在4．5－5．5h,污泥负荷为0．14－0．26kgBOD5/(kgMLSS.d)时,出水BOD5浓度为5．12－13．62mg/L,去除率达85％－93％;出水COD浓度为10．7－32．2mg/L,去除率达82％－88％;出水NH3－N浓度为2．83－9．23mg/L,去除率达53％－87％;出水TP浓度为0．1－0．45mg/L,去除率达85％－99％。     

投粉末炭MBR处理微污染原水研究

采用投加粉末活性炭的膜生物反应器处理微污染原水，结果表明，对CODMn、氨氮和浊度的平均去除率分别为59．4％、93．5％和99．6％，出水水质与常规处理——臭氧活性炭工艺的大体相当，并且不需投加混凝剂，同时还减少了投氯量。     

原水及常规处理出水的SS粒径分布

以上海的两座水厂为例，分别对其原水（长江、黄浦江水）和常规工艺的处理水进行颗粒计数和有机物测定，并对测定结果进行了分析和对比，原水中绝大部分的SS粒径＜5μm（长江占89．38％，黄浦江占94．68％），经沉淀与过滤可去除98％左右的SS颗粒，平均每去除原水中10％的SS颗粒，相应于去除2％－5％的溶解性UV260和1％－2％左右的DOC。     

ABR-BAF工艺处理采油废水的中试研究

进行了利用折流板厌氧反应器（ABR）-曝气生物滤池（BAF）工艺处理江汉油田马-25污水处理站采油废水的中试研究，主要考察了ABR的除油效果、提高废水可生化性的作用以及BAF的运行参数、处理效果等。研究结果表明：当废水流量为0．3m^3／h时，ABR反应器对油的去除率平均为83．5％，对COD的去除率平均为40．8％，出水BOD，／COD值提高了24．8％。ABR一方面去除了采油废水中的大部分油，另一方面提高了采油废水的可生化性。当BAF的水力负荷为0．6m／h、进水COD平均为203．5mg／L时，出水COD平均为85．7mg／L，平均去除率为57．9％；对SS的去除率为82．7％。组合工艺对油、COD、BOD，和SS的总去除率分别为96．1％-96．9％、58．2％～75．1％、80．0％-93．1％和80．7％～87．1％。扫描电镜（SEM）观察结果显示：生物膜结构紧密，并且观察到裂口虫，生物相非常丰富。ABR-BAF工艺能够很好地处理采油废水，出水水质满足污水二级排放标准。     

多级悬浮填料生物反应器处理石化废水

采用多级悬浮填料生物反应器处理石化废水，在填料投加率为50％、水力停留时间为8h的工况条件下，当进水BOD5为108－234mg/L,CODcr为253．4－444．6mg/L,NH3-N为20．8－26．2mg/L时，二级反应器对其平均去除率分别为90．7％、74％和53．2％；三级反应器对其平均去除率分别为93．7％、77．7％和84．6％，这说明采用多级反应器在保证有效去除BOD、COD等有机污染物的同时，可以大大提高对NH3－N的去除效果。     

移动床生物膜法处理表面活性剂废水

采用混凝/水解／好氧移动床生物膜工艺处理表面活性剂废水，运行结果表明，该工艺对COD、BOD5、SS、LAS、TCC-TCS的平均去除率分别为92．7％、95．3％、91．3％、96．9％和100％，出水水质达到《污水综合排放标准》(GB8978-1996)的二级标准。     

两种膜生物反应器处理印染废水的比较

考察了上流式接触氧化柱和接触氧化槽与膜系统组成的分离式膜生物反应器处理印染废水的效果，上流式接触氧化柱－膜反应器和接触氧化槽－膜反应器对COD的平均去除率分别为64．3％和81．7％，对色度的平均去除率分别为59．7％和41％。     

化学氧化破坏藻体及胞内藻毒素释放特性研究

借助透射电子显微镜（TEM）并利用胞内、外微囊藻毒素分析技术,研究了受污染源水中铜绿微囊藻在几种水厂常用化学氧化剂作用下的藻体破坏形态特征,探讨了胞内藻毒素的释放特性及氧化剂对藻毒素的去除效果.结果表明,氯、臭氧和二氧化氯均能引起藻体破坏及胞内藻毒素的释放,其中臭氧对藻体形态的破坏最为严重,氯的作用相对较差,二氧化氯则介于二者之间;在氧化剂低投量（0.5 mg/L）下,二氧化氯引起胞内藻毒素的释放最为显著,臭氧对藻毒素的去除效果优于二氧化氯和氯.从藻毒素的安全去除角度考虑,在水处理过程中应该首选臭氧,其次为二氧化氯,氯的使用应当慎重.     

Integration of dissolved gas flotation and nanofiltration for M. aeruginosa and associated microcystins removal

The removal of Microcystis aeruginosa and associated microcystins was investigated by a dissolved gas flotation (preceded by coagulation/flocculation)-nanofiltration (NF) sequence. The experiments were conducted with a freshwater spiked with M. aeruginosa cell aggregates to simulate a naturally occurring bloom. Two types of gases were used in the flotation pre-treatment, air (DAF) and a mixture of CO(2)/air. Very good results in terms of NF fluxes, overall removal efficiencies and final water quality were achieved with both sequences. However, the CO(2)/air mixture presented no benefit to the overall sequence, both in terms of toxin release to water during flotation and lower natural organic matter removal by NF, which was due to an overall negative effect of the acid pH. NF was able to completely remove cyanobacteria (100% removal efficiency of chlorophyll a) and microcystins (always under the quantification limit), regardless of the pre-treatment used and the water recovery rate (up to 84%). Therefore, DAF-NF sequence is a safe barrier against M. aeruginosa and microcystins in drinking water. In addition, it ensures an excellent control of particles, disinfection by-products formation, and other micropollutants that may be present in raw water.     

Neurotoxic and hepatotoxic cyanotoxins removal by nanofiltration

This study investigates the influence of chemical feed characteristics on nanofiltration performance for cyanotoxins removal, namely the neurotoxic anatoxin-a (alkaloid of 166 g/mol, positively charged) and the hepatotoxic microcystins (cyclic peptides of approximately 1,000 g/mol, negatively charged). Results indicate that NF membranes are an effective barrier against anatoxin-a and microcystins in drinking water. Anatoxin-a and especially microcystins were almost completely removed, regardless of the variations in feed water quality (natural organic matter and competitive toxin), the water recovery rate and the pH values. Anatoxin-a removal was governed by electrostatic interactions and steric hindrance, whereas for microcystins the latter was the main mechanism. In turn, fluxes were significantly impacted by background organics and, especially, inorganics (pH, calcium).     

Elimination of microcystins by water treatment processes-examples from Sulejow Reservoir, Poland

Eutrophication is a serious problem in Polish freshwaters. Mass occurrences of toxic cyanobacteria in reservoirs cause problems in the production of safe drinking water and the diversity of produced toxins complicates monitoring of freshwaters. The aim of this study was to estimate the efficiency of water treatment processes in the removal of microcystins (MCs), cyanobacterial hepatotoxins. Elimination of microcystins was studied at two waterworks, which supply drinking water to the city of Lodz from Sulejow Reservoir. The consecutive steps of pre-oxidation, coagulation, sand filtration, ozonation and chlorination used in the water treatment showed effective elimination of microcystins in water from Sulejow Reservoir in 2002 and 2003. The highest total concentration of microcystin (variants MC-RR, MC-YR, MC-LR) amounted to 6.7 microgl(-1) in raw water and was detected on the 13th of August 2002. In 2003 the water utility decided to increase the contribution of ground water in the production of drinking water. This resulted in a decrease of microcystin in water during and after the treatment process. The current management strategy of the waterworks company includes mixing of surface water and ground water, which reduces the hazards caused by toxic cyanobacterial blooms in the reservoir.     

福州市东南区水厂原水生物预处理试验研究

采用悬浮填料生物接触氧化法对福州市东南区水厂的微污染原水进行预处理,考察了该工艺的处理效果及影响因素,并针对原水中污染物的周期性变化规律,提出了可行的工艺设计参数和建议。结果表明,当原水的氨氮和CODMn分别为(0.15~2.0)、(2~4.1)mg/L时,在HRT为1 h、气水比为1∶1的工况下,生物接触氧化工艺对氨氮和CODMn的去除效果较好,平均去除率分别可达70%以上和15%左右。随HRT的缩短、水温的降低及气水比的减小,系统对氨氮的去除效果会相应下降,但原水的水温基本满足工艺的要求,而要保持填料的流化状态,曝气量需在2m3/(m2.h)以上。可行的生物预处理工艺设计参数:采用两级生物接触氧化工艺串联运行,总HRT为45~60 min、总气水比为(0.8~1.2)∶1。     

曝气生态浮床/PRB组合工艺净化重污染河水研究

通过中试考察了曝气生态浮床/可渗滤反应墙(EAFB-PRB)组合工艺对重污染河水的净化效果.结果表明:组合工艺对COD、TN、NH_4~+-N和TP都有较好的去除效果,平均去除率分别为79.5%、27.9%、36.8%和87.0%;经处理后,水体的平均DO浓度由0.09 mg/L提高到1.7mg/L;对TSS的平均去除率达95.4%,出水清澈透明,感官效果好.可见,该组合工艺是改善重污染河水水质的有效方法.     

液氯消毒工艺去除微囊藻毒素的试验研究

通过小试研究了氯消毒工艺对黄浦江水中两种微囊藻毒素的去除效果及对水厂实际运行的意义.结果表明,游离氯对试验中所研究的两种微囊藻毒素(MC-LR、MC-RR)具有一定的去除效果,两种微囊藻毒素的氯化降解过程均符合二级反应动力学模型,通过提高游离氯的浓度和持续时间,可以显著提高微囊藻毒素的降解速率;在pH值为7.25时,将黄浦江水中10 μg/L的MC-LR降至国家水质标准中的要求值(1μg/L)所需要的cT值为107.99 mg·min/L,正常消毒条件下难以达到此值;但氯消毒工艺能够明显降低微囊藻毒素的急性毒性,可以作为目前控制水中微囊藻毒素脱毒的一种手段.     

Significance of microcystin production by benthic communities in water treatment systems of arid zones

The study of the dynamics of phytobenthic and phytoplankton communities was undertaken, during a year, in the regulation reservoir associated with a water treatment plant (WTP), which provides the city of Murcia (Spain) with drinking water. Water samples were collected in different stages of the treatment. In the reservoir, the presence of dissolved and intracellular microcystins is constant, both in benthos and in plankton. The collected samples show a positive correlation between the dissolved microcystins and the benthic ones in the reservoir itself, as well as in an upstream reservoir (Ojós Reservoir). The treatment process (ozone+clarification+ozone+activated carbon) is very effective in the removal of toxins, and the drinking water produced is totally free of microcystins. The incorporation of the benthic communities in the routine check for the presence of microcystins is recommended, since it is not compulsory according to the current legislation.     

中桥水厂超滤膜深度处理工艺中试研究

分别以滤后水和沉后水作为进水,考察了超滤膜深度处理工艺的净水效能、膜通量、渗透性及清洗方式.结果表明,超滤膜深度处理工艺对浊度、总铁及色度具有较好的去除效果;以滤后水和沉后水作为超滤膜进水时,适宜的膜通量范围分别为(70 ～80)和(50～60) L/(m2·h);超滤膜-粉末活性炭组合工艺对浊度的去除效果很好,当PAC投加量为15 mg/L时,浊度去除率大于80.7％,TOC、CODMn 、UV254及氨氮去除率基本小于30％.