臭氧活性炭工艺中卤乙酸生成潜能与相对分子质量分布关系的研究

通过臭氧生物活性炭和微曝气生物活性炭(O₃/BAC和micro-aeration/BAC)2套工艺研究其对不同相对分子质量有机物去除特点和不同相对分子量有机物生成的卤乙酸及其去除特性.结果表明,O₃/BAC工艺对相对分子质量区间>30×10³的有机物去除率超过90%.O₃/BAC与micro-aeration/BAC出水中,UV₂₅₄值表示相对分子质量<103的有机物超过50%,相对分子量区间在10×10³～30×10³的有机物占20%～30%;在O₃/BAC和微曝气/BAC工艺出水中,以相对分子质量<10³的有机物生成的卤乙酸最多,生成DCAA、TCAA、DBAA分别为97.00、38.55、2.10μg/L和104.00、42.75和2.92μg/L;采用各处理单元不同分子量有机物与氯反应生成的DCAA、TCAA、DBAA和THAAs与相对应的UV₂₅₄值进行线性拟合,相关系数分别为0.827、0.851 3、0.815 7和0.878.UV₂₅₄与臭氧生物活性炭处理工艺出水中的卤乙酸生成潜能具有较好的线性关系.     

Contribution of anthropogenic pollutants to the increase of tropospheric ozone levels in the Oporto Metropolitan Area, Portugal since the 19th century

The main purpose of this study was to evaluate the contribution of anthropogenic pollutants to the increase of tropospheric ozone levels in the Oporto Metropolitan Area (Portugal) since the 19th century. The study was based on pre-industrial and recent data series, the results being analyzed according to the atmospheric chemistry. The treatment of ozone and meteorological data was performed by classical statistics and by time-series analysis. It was concluded that in the 19th century the ozone present in the troposphere was not of photochemical origin, being possible to consider the respective concentrations as reference values. For recent data a cycle of 8h for ozone concentrations could be related to traffic. Compared to the 19th century, the current concentrations were 147% higher (252% higher in May) due to the increased photochemical production associated with the increased anthropogenic emissions.     

黄孢原毛平革菌(Phanerochaete chrysosporium)对3种酚酸物质的降解作用

研究黄孢原毛平革菌(P.chrysosporium)对香草酸、阿魏酸、对羟基苯甲酸的降解作用.结果表明,300 μg/mL的上述3种酚酸物质与黄孢原毛平革菌共培养2 d后,3种酚酸物质的降解率分别达到73.48%、99.09%和54.74%.黄孢原毛平革菌发酵上清液对3种酚酸物质的降解能力较弱,作用2 d后,降解率分别为13.28%,4.47%和5.43%,而该菌菌丝体降解能力很强,作用2 d后3种酚酸物质的降解率分别达到65%,98.37%和48.69%.研究表明,黄孢原毛平革菌对这3种酚酸的降解主要在菌体表面或体内进行.     

二氯异氰脲酸钠和三氯异氰脲酸对棕囊藻细胞去除的研究

研究了二氯异氰脲酸钠和三氯异氰脲酸对球形棕囊藻的灭杀和控制作用,及其投药时间对除藻效果的影响,并比较2种药剂的除藻效果,初步探讨了除藻机理.结果表明,这2种除藻剂可以缓释次氯酸,提高其稳定性,有较长的药效期.当有效氯浓度达到4.5mg/L时,2种药剂均能有效地控制和灭杀球形棕囊藻,具有高效、低毒的优点.有效氯浓度为5.0mg/L,藻细胞去除率在24h可达到90%以上.在等于和大于5.0mg/L有效氯浓度时,三氯异氰脲酸的除藻效果优于二氯异氰脲酸钠,通过对2种药剂除藻率的t检验进一步证实了这一结论.     

Perfluorinated Surfactants in Surface and Drinking Waters (9 pp)

Background, Aim and Scope In this paper recent results are provided of an investigation on the discovery of 12 perfluorinated surfactants (PS) in different surface and drinking waters (Skutlarek et al. 2006 a, Skutlarek et al. 2006 b). In the last years, many studies have reported ubiquitous distribution of this group of perfluorinated chemicals, especially perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in the environment, particularly in wildlife animal and human samples (Giesy and Kannan 2001, Houde et al. 2006, Prevedouros et al. 2006). Perfluorinated surfactants (e.g. PFOS and PFOA) have shown different potentials for reproductory interference and carcinogenity in animal experiments as well as partly long half-lives in humans (Guruge et al. 2006, FSA UK 2006a, FSA UK 2006b, 3M 2005, OECD 2002, Yao and Zhong 2005). They possess compound-dependent extreme recalcitrance against microbiological and chemical degradation and, in addition, they show variable potentials for bioaccumulation in animals and humans (Houde et al. 2006). Materials and Methods: Surface and drinking water samples were collected from different sampling sites: - Surface waters: samples taken from the rivers Rhine, Ruhr, Moehne and some of their tributaries. Further samples were taken from the Rhine-Herne-Canal and the Wesel-Datteln-Canal. - Drinking waters: samples taken in public buildings of the Rhine-Ruhr area. After sample clean-up and concentration by solid-phase extraction, the perfluorinated surfactants were determined using HPLC-MS/MS. Results: All measured concentrations (sum of seven mainly detected components) in the Rhine river and its main tributaries (mouths) were determined below 100 ng/L. The Ruhr river (tributary of the Rhine) showed the highest concentration (94 ng/L), but with a completely different pattern of components (PFOA as major component), as compared with the other tributaries and the Rhine river. Further investigations along the Ruhr river showed remarkably high concentrations of PS in the upper reaches of the Ruhr river and the Moehne river (tributary of the Ruhr) (Ruhr: up to 446 ng/L, Moehne: up to 4385 ng/L). The maximum concentration of all drinking water samples taken in the Rhine-Ruhr area was determined at 598 ng/L with the major component PFOA (519 ng/L). Discussion: The surface water contaminations most likely stem from contaminated inorganic and organic waste materials (so-called 'Abfallgemisch'). This waste material was legally applied to several agricultural areas on the upper reaches of the Moehne. Perfluorinated surfactants could be detected in some suchlike soil samples. They contaminated the river and the reservoir belonging to it, likely by superficial run-off over several months or probably years. Downstream, dilution effects are held responsible for decreasing concentrations of PS in surface waters of the Moehne and the Ruhr river. In analogy to the surface water samples, PS (major component PFOA) can be determined in many drinking water samples of the Rhine-Ruhr area where the water supplies are mainly based on bank filtration and artificial recharge. Conclusions: The concentrations found in drinking waters decreased with the concentrations of the corresponding raw water samples along the flow direction of the Ruhr river (from east to west) and were not significantly different from surface water concentrations. This indicates that perfluorinated surfactants are at present not successfully removed by water treatment steps. Recommendations and Perspectives: Because of their different problematic properties (persistence, mobility, toxicity, bioaccumulation), the concentrations of specific perfluorinated surfactants and their precursors in drinking waters and food have to be minimised. Therefore, it is of utmost importance to take the initiative to establish suitable legal regulations (limitations/ban) concerning the production and use of these surfactants and their precursors. Furthermore, it is indispensable to protect water resources from these compounds. A discussion on appropriate limit values in drinking water and foodstuffs is urgently needed. Concerning the assumed soil contamination, the corresponding regulation (Bioabfall-Verordnung 1998 – Regulation on Organic Waste 1998) should be extended to allow the control of relevant organic pollutants.     

Titration Curves: A Useful Instrument for Assessing the Buffer Systems of Acidic Mining Waters (10 pp)

Background, Aims and Scope The acidification of mine waters is generally caused by metal sulfide oxidation, related to mining activities. These waters are characterized by low pH and high acidity due to strong buffering systems. The standard acidity parameter, the Base Neutralization Capacity (BNC) is determined by endpoint titration, and reflects a cumulative parameter of both hydrogen ions and all buffering systems, but does not give information on the individual buffer systems. We demonstrate that a detailed interpretation of titration curves can provide information about the strength of the buffering systems. The buffering systems are of importance for environmental studies and treatment of acidic mining waters. Methods Titrations were carried out by means of an automatic titrator using acidic mining waters from Germany and Canada. The curves were interpreted, compared with each other, to endpoint titration results and to elemental concentrations contained therein. Results and Discussion The titration curves were highly reproducible, and contained information about the strength of the buffer systems present. Interpretations are given, and the classification and comparison of acidic mining waters, by the nature and strength of their buffering systems derived from titration curves are discussed. The BNC-values calculated from the curves were more precise than the ones determined by the standard endpoint titration method. Due to the complex buffer mechanisms in acidic mining waters, the calculation of major metal concentrations from the shape of the titration curve resulted in estimates, which should not be confused with precise elemental analysis results. Conclusion Titration curves provide an inexpensive, valuable and versatile tool, by which to obtain sophisticated information of the acidity in acidic water. The information about the strength of the present buffer systems can help to understand and document the complex nature of acidic mining water buffer systems. Finally, the interpretation of titration curves could help to improve treatment measurements and the ecological understanding of these acidic waters.     

粉煤灰对水中酸性品红的吸附研究

以粉煤灰为吸附剂,研究了粉煤灰对酸性品红的吸附效果。选取了粒径、投加量、温度、时间、转速、染料浓度6个因素进行单因素实验,研究了各个因素对粉煤灰的影响,研究表明,粉煤灰对酸性品红的吸附效果很好,最高去除率可达99.63%;并且从热力学和动力学两方面对粉煤灰吸附酸性品红的过程进行拟合,结果表明,粉煤灰对酸性品红吸附的热力学过程比较符合模型Langmuir EXT1,动力学过程比较符合准一级吸附动力学方程Box Lucas1。     

广州市酸沉降对材料破坏的经济损失估算

大气中的酸性物质对材料的破坏是酸沉降经济损失中的重要部分。简要说明了材料损失的计算方法,并以2001年为基准年,选择了广州市作为代表性城市,运用材料损伤函数和材料使用寿命公式对建筑材料及自行车的经济损失进行了估算,使酸沉降的破坏作用达到定量化。     

清洁生产理论基础

重点分析了清洁生产的物流基础、价值基础、经济基础,并与末端治理对比,从而论证了清洁生产是实现经济效益和环境效益的最佳模式,是实现可持续发展的必然选择。     

化工企业清洁生产的环境与经济效益分析

化工企业实施清洁生产的实践表明,注重工艺改革与投资,使废弃物转化为资源,使污染物转变为利润,清洁生产显示出显著的环境与经济效益。