Fe-Cu催化还原法处理废水的稳定性分析

采用扫描电镜(SEM)和X射线衍射(XRD)技术对Fe-Cu催化还原法处理硝基苯配水反应前后铁屑和铜的表面进行分析,研究了Fe-Cu催化还原法的长期运行效果.结果表明,运行数周后铜表面性状基本保持不变,化学稳定性好,抗中毒能力强.处理效果的下降主要起因于铁屑表面的金属铁发生反应而被逐渐消耗,以及铁屑表面为沉淀物覆盖而逐渐失效.     

无机陶瓷纳滤膜分离高钠盐废水中的锶

本实验研究表明,仅用截留分子量为1000的无机陶瓷纳滤膜分离高钠盐模拟溶液中的锶,分离效果并不理想.为提高陶瓷纳滤膜对锶的选择分离效果,选择了分子量为3000的聚丙烯酸作为陶瓷纳滤膜分离的强化剂,重点探讨了溶液pH值、聚丙烯酸浓度、温度及离子强度对模拟溶液盐分离效果和膜通量的影响,并得到了适宜的锶钠分离条件.实验结果表明,在适宜条件下,通过聚丙烯酸强化和两级分离,陶瓷纳滤膜可大大提高模拟溶液中锶离子的选择分离效果,锶/钠的分离因子高达205.     

酸解破乳作用处理高含固率洗毛废水的研究

洗毛废水是一种高浓度有机废水,含固率高,主要成分是羊毛脂、羧酸盐和土杂,由于强极性物质的存在和胶体强的负电性,导致洗毛废水形成稳定的乳化体系.本试验通过加入硫酸改变洗毛废水的有机组成,降低体系的Zeta电位,破坏体系的稳定性,从而使得有机物发生凝聚沉降,达到去除COD的目的.硫酸加入量达到0.2%或以上时对洗毛废水中SS的自然沉降性、絮凝性和极性有很大影响,比阻从远大于9.81×1013m/kg,下降为5.54×1010m/kg,COD去除率达到86.8%,SS去除率达到98%.因此,洗毛废水加酸处理后通过机械脱水,实现固液分离,以降低原废水的色度和大幅降低COD的方式,是可供考虑的处理工艺.     

焦炭和废铁屑微电解预处理垃圾渗滤液的研究

研究表明,废铁屑和焦炭微电解是预处理垃圾渗滤液的一种有效方法,可去除垃圾渗滤液COD、色度和腐殖酸等污染物质,改善其可生化性、降低负荷,为后续生化处理创造良好的条件.通过静态正交实验确定废铁屑和焦炭最佳投加体积比为1∶3;最佳反应pH值为4;动态实验中,反应时间为1 h时,COD和色度去除率分别高达68%和91%;BOD/COD从0.3提高到0.5左右.     

悬浮颗粒物在河道滞留塘系统中的沉降与沉积特性

河道滞留塘系统是以颗粒物沉降为污染物主要净化机理的污染河流净化技术.通过1年的现场试验研究,考察了悬浮颗粒物SS在滞留塘中的沉降和沉积特性.在本试验条件下,随水力停留时间(HRT)延长(HRT为1.5～7 h),SS平均去除率逐渐增加,介于20%～40%之间,而SS去除速率则快速降低,SS去除速率与进水SS浓度成正比关系;不同季节河水中SS的沉降性能有较大差异,冬季河水中有机物含量较低的易沉降颗粒物比例较春秋季河水的为高,滞留塘HRT的选择应以去除易沉降颗粒物为标准,本研究条件下5 h以内是适宜的HRT选择范围.在滞留塘动态运行中,SS的沿程沉积量呈指数规律下降.     

膜生物反应器在污水处理中的应用现状及展望

综述了膜生物反应器（MBR）的研究进展，介绍了其分类及特点、处理机理与MBR运行的影响因素以及膜污染的控制等，并概括了MBR的发展及展望。MBR是近来发展较迅速的一种污水治理设备，具有占地少、能耗低等优点，但也存在一定的缺点，其中膜污染是影响其推广应用的主要因素，目前国内外学者一般都以膜污染作为切入点进行研究，通过改变料液性质、优化操作参数、提高膜清洗效率等方法得以防治膜污染。     

射流曝气的气液两相流的数值模拟

射流曝气在活性污泥处理方法中起着重要的作用。采用数值模拟的方法研究自吸式单级单喷射流器中的气液两相流动状况，通过对不同长径比和喷嘴面积比的射流曝气器模型的气液两相流的计算，定量分析长径比和喷嘴面积比对射流曝气器流场和空气与工作介质流量比的影响，为进一步设计开发新型高效的射流曝气器提供参考。     

生物膜与A／O工艺耦合快速降解氨氮

应用由城市污水处理厂序批式间歇反应器（SBR）中筛选得到的4株特殊氨氧化菌，分别在SBR和有回流的生物膜与A／O工艺耦合体系培养中，考察其降解低碳高氨氮废水的功能。结果表明，自养硝化与异养氨氧化菌的混合菌群较单一自养硝化菌株降解氨氮速率快；在生物膜与A／O工艺耦合系统中，自养硝化与异养氨氧化菌协同代谢加速氨氮氧化脱除，氨氮脱除速率远比SBR系统快。对生物膜与A／O工艺耦合系统中氨氮脱除动力学进行了研究，模拟了NH4^＋、NO2^-；质量浓度与氨氮脱除比速率之间的关系，模型得到了较好的验证。     

常规水处理厂中小隐孢子虫卵囊的去除效果

介绍了小隐孢子虫卵囊的特点及其对人体的危害，分析了pH、混凝剂种类与投加量、电导率和天然有机物含量等对小隐孢子虫卵囊的Zeta电位的影响，总结了混凝－沉淀－过滤和直接过滤对小隐孢子虫卵囊的去除效果，探讨了水温、水质、混凝剂种类与投加量、滤料层组成和滤速等对去除效果的影响。     

Ozone pollution and ozone biomonitoring in European cities. Part I: Ozone concentrations and cumulative exposure indices at urban and suburban sites

In the frame of a European research project on air quality in urban agglomerations, data on ozone concentrations from 23 automated urban and suburban monitoring stations in 11 cities from seven countries were analysed and evaluated. Daily and summer mean and maximum concentrations were computed based on hourly mean values, and cumulative ozone exposure indices (Accumulated exposure Over a Threshold of 40 ppb (AOT40), AOT20) were calculated. The diurnal profiles showed a characteristic pattern in most city centres, with minimum values in the early morning hours, a strong rise during the morning, peak concentrations in the afternoon, and a decline during the night. The widest amplitudes between minimum and maximum values were found in central and southern European cities such as Düsseldorf, Verona, Klagenfurt, Lyon or Barcelona. In the northern European cities of Edinburgh and Copenhagen, by contrast, maximum values were lower and diurnal variation was much smaller. Based on ozone concentrations as well as on cumulative exposure indices, a clear north–south gradient in ozone pollution, with increasing levels from northern and northwestern sites to central and southern European sites, was observed. Only the Spanish cities did not fit this pattern; there, ozone levels were again lower than in central European cities, probably due to the direct influence of strong car traffic emissions. In general, ozone concentrations and cumulative exposure were significantly higher at suburban sites than at urban and traffic-exposed sites. When applying the newly established European Union (EU) Directive on ozone pollution in ambient air, it was demonstrated that the target value for the protection of human health was regularly surpassed at urban as well as suburban sites, particularly in cities in Austria, France, northern Italy and southern Germany. European target values and long-term objectives for the protection of vegetation expressed as AOT40 were also exceeded at many monitoring sites.