超声波处理剩余活性污泥促进厌氧消化

用超声波处理剩余活性污泥(简称污泥),考察了污泥絮体结构、污泥中溶解性化学需氧量(SCOD)的变化规律及超声波处理对污泥厌氧消化的影响。实验结果表明,声强大于1 040W/m2时,用超声波处理污泥30m in以上,污泥絮体被打碎,污泥絮体结构遭到严重破坏,污泥中SCOD迅速增加,加速了污泥中有机质的水解反应;声强为2 000W/m2时,用超声波处理污泥60m in,中温((37±1)℃)厌氧消化10d,COD去除率为41%;厌氧消化25d的总产气量比未经超声波处理的污泥总产气量提高了53%;将发酵罐容积放大10倍,经超声波处理的污泥25d累积的总产气量比未经超声波处理的污泥总产气量提高了约25%。     

Local and regional air pollution in Ireland during an intensive aerosol measurement campaign

An intensive two month measurement campaign has been performed during a two year study of major component composition of urban PM10 and PM2.5 in Ireland (J. Yin, A. G. Allen, R. M. Harrison, S. G. Jennings, E. Wright, M. Fitzpatrick, T. Healy, E. Barry, D. Ceburnis and D. McCusker, Atmos. Res., 2005, 78(3-4), 149-165). Measurements included size-segregated mass, soluble ions, elemental carbon (EC) distributions, fine and coarse fraction organic carbon (OC) and major gases along with standard meteorological measurements. The study revealed that urban emissions in Ireland had mainly a local character and therefore were confined within a limited area of 20-30 km radius, without significantly affecting regional air quality. Gaseous measurements have shown that urban emissions in Ireland had clear, but fairly limited influence on the regional air quality due to favorable mixing conditions at higher wind speeds, in particular from the western sector. Size-segregated mass and chemical measurements revealed a clear demarcation size between accumulation and coarse modes at about 0.8 microm which was constant at all sites. Carbonaceous compounds at the urban site accounted for up to 90% of the particle mass in a size range of 0.066-0.61 microm. Nss SO4(2-) concentrations in PM2.5 were only slightly higher at the urban site compared to the rural or coastal sites, while NO3- and NH4+ concentrations were similar at the urban and coastal sites, but were a factor of 2 to 3 higher than at the rural site. OC was highly variable between the sites and revealed clear seasonal differences. Natural or biogenic OC component accounted for <10% in winter and up to 30% in summer of the PM2.5 OC at urban sites. A contribution of biogenic OC component to PM2.5 OC mass at rural site was dominant.     

应用水解+A/O工艺治理化工废水的工程实践

兰州石化公司应用水解(酸化)+AO工艺组合治理化工废水。化工废水经水解(酸化)处理后,BOD5CODCr比值从<0.2提高到0.37,提高了化工废水的可生化性。该工艺利用兼氧和好氧微生物对高浓度化工废水处理后,CODCr的去除率达85%以上,NH3N的去除率达95%以上。     

射阳河底泥重金属沿程变化分析及污染评价

分析了射阳河流域沿程20个底泥样品中6种重金属(Cr、Pb、Ni、Zn、Cu、As)的含量,并应用地累积指数法对其进行了污染评价。研究结果表明:除As在近一半的采样点没有污染,其他重金属污染均普遍存在,但多数属于轻度污染。Zn污染最为严重,几乎全程都是偏中等或中等以上的污染。纵观射阳河全程样品FN04,SY07污染最为严重,前者与其支流西塘河的污染有关,后者可能与河闸上侧的死水状态有关;黄沙河污染最轻,与河流沉积物粒径比较粗而导致的对重金属吸附能力减弱有关。     

城市污水处理厂除臭技术

介绍了城市污水处理厂臭气来源、成分及产量.针对目前国内外除臭技术的研究和发展情况,分析了污水处理厂的各种物理、化学和生物除臭方法的技术原理、优缺点和应用现状.结合日本城市污水处理厂的运行实际,重点介绍了一种不产生臭气的新技术--腐殖活性污泥法的工艺流程、特点及其应用现状.     

2-羟基-5-磺酸基苯基重氮氨基偶氮苯光度法测定微量Ni(Ⅱ)的研究

2—羟基— 5—磺酸基苯基重氮氨基偶氮苯与 Ni( )在 OP存在下 ,于 p H=1 0的硼砂缓冲溶液中形成 2∶ 1红色络合物 ,λmax=530 nm,ε=6.0× 1 0 4 L· mol- 1·cm- 1 ,Ni( )含量在 0～ 0 .2 4 mg/ L符合比耳定律。用于电镀废水中镍的测定 ,结果满意。     

昆明滇池砷形态分布研究

采用离子交换和溶剂萃取相结合的分离;富集技术,事等离子体发射光谱仪（ＩＣＰ－ＡＥＳ）测定,对昆明滇池７个取样点的砷形态进行了分离和必滇池环境对池中砷形态的迁移转化进行了探讨,为滇池砷污染的研究和治理提供了一定依据。     

A docking-based receptor library of antibiotics and its novel application in predicting chronic mixture toxicity for environmental risk assessment

As organisms are typically exposed to chemical mixtures over long periods of time, chronic mixture toxicity is the best way to perform an environmental risk assessment (ERA). However, it is difficult to obtain the chronic mixture toxicity data due to the high expense and the complexity of the data acquisition method. Therefore, an approach was proposed in this study to predict chronic mixture toxicity. The acute (15 min exposure) and chronic (24 h exposure) toxicity of eight antibiotics and trimethoprim to Vibrio fischeri were determined in both single and binary mixtures. The results indicated that the risk quotients (RQs) of antibiotics should be based on the chronic mixture toxicity. To predict the chronic mixture toxicity, a docking-based receptor library of antibiotics and the receptor-library-based quantitative structure–activity relationship (QSAR) model were developed. Application of the developed QSAR model to the ERA of antibiotic mixtures demonstrated that there was a close affinity between RQs based on the observed chronic toxicity and the corresponding RQs based on the predicted data. The average coefficients of variations were 46.26 and 34.93 % and the determination coefficients (R ²) were 0.999 and 0.998 for the low concentration group and the high concentration group, respectively. This result convinced us that the receptor library would be a promising tool for predicting the chronic mixture toxicity of antibiotics and that it can be further applied in ERA.     

Dissipation and residue of MCPA (4-chloro-2-ethylphenoxyacetate) in wheat and soil

A rapid and simple HPLC method has been developed for the quantitation of 4-chloro-2-methylphenoxyacetic acid (MCPA) in both wheat and soil samples. Samples were extracted in acidic media and cleaned up by solid-phase extraction with C(18) cartridges before HPLC-DAD detection. The limits of detection and quantification of MCPA were 0.02 ng and 0.01 mg/kg for both wheat and soil. The mean recoveries ranged from 87.1% to 98.2%, and the RSDs ranged from 0.604% to 3.44% for the three spiked levels (0.01, 0.1, 0.5 mg/kg). The proposed method was successfully applied to the analysis of MCPA residues in wheat and soil samples from an experimental field. The dissipation half-lives in soil were calculated to be 3.22 days (Beijing) and 3.10 days (Tianjin), respectively. Direct confirmation of the analytes in real samples was achieved by gas chromatography-mass spectrometry. The results indicated that at harvest time, the residues of MCPA in wheat were well below the maximum residue levels and were safe to apply in wheat.     

南京某地甲苯槽罐车燃烧事故应急监测案例分析与思考

突发性环境污染事故不仅破坏生态环境,制约社会发展,更威胁人类健康.环保部门如何加强应急监测能力建设,科学合理地处理应急监测中出现的问题,显得尤为重要.对一起突发性环境污染事故应急监测各个环节的优缺点进行了分析和思考,总结经验并提出建议,为同类突发环境污染事故的应急监测提供借鉴.