Polar organic chemical integrative sampler (POCIS): application for monitoring organic micropollutants in wastewater effluent and surface water

In this paper, we discuss the advantages and drawbacks of POCIS (Polar Organic Chemical Integrative Sampler) for the evaluation of river water quality downstream of wastewater treatment plants. POCIS proved well adapted to sampling alkylphenols and several pharmaceuticals. Concentration factors and the decrease in limits of quantification, compared to grab water sample analyses, were significant except for hormones, β-blockers and bronchodilators. Promising preliminary results obtained in situ on deuterated atenolol used as a performance reference compound need to be confirmed in-lab. This work confirms that POCIS is a valuable tool for monitoring hydrophilic organic molecules in river and wastewaters.     

三维电极电化学反应器深度处理焦化废水

为探索焦化废水深度处理新途径,采用了焦粒、活性炭负载Mn（NO3）2和Zn（NO3）2化合物粒子电极为第3极的三维电极反应器对二级生化处理后的焦化废水进行深度处理。考察了焦化废水中有机物去除的影响因素及处理效果,并探讨了有机物的降解动力学。结果表明,以焦粒为载体的粒子电极三维电极系统在pH为6.5,电导率为4 580μS/cm,电流密度为16 mA/cm2,投加量大于25 g/L时,降解20 min,COD去除率超过35%以上。焦化废水的降解的动力学研究表明,焦化废水降解符合表观一级反应动力学规律。该研究可为三维电极反应器在焦化废水深度处理工程应用中提供参数依据。     

Impact of wastewater treatment plants on receiving surface waters and a tentative risk evaluation: the case of estrogens and beta blockers

Five estrogenic hormones (unconjugated?+?conjugated fractions) and 10 beta blockers were analyzed in three wastewater treatment plant (WWTP) effluents and receiving river waters in the area of Lyon, France. In the different samples, only two estrogens were quantified: estrone and estriol. Some beta blockers, such as atenolol, acebutolol, and sotalol, were almost always quantified, but others, e.g., betaxolol, nadolol, and oxprenolol were rarely quantified. Concentrations measured in river waters were in the nanogram per liter range for estrogens and between 0.3 and 210 ng/L for beta blockers depending on the substance and the distance from the WWTP outfall. The impact of the WWTP on the receiving rivers was studied and showed a clear increase in concentrations near the WWTP outfall. For estrogens, the persistence in surface waters was not evaluated given the low concentrations levels (around 1 ng/L). For beta blockers, concentrations measured downstream of the WWTP outfall were up to 16 times higher than those measured upstream. Also, the persistence of metoprolol, nadolol, and propranolol was noted even 2 km downstream of the WWTP outfall. The comparison of beta blocker fingerprints in the samples collected in effluent and in the river also showed the impact of WWTP outfall on surface waters. Finally, a tentative environmental risk evaluation was performed on 15 sites by calculating the ratio of receiving water concentrations to predicted non-effect concentrations (PNEC). For estrogens, a total PNEC of 5 ng/L was considered and these substances were not linked to any potential environmental risk (only one site showed an environmental risk ratio above 1). Unfortunately, few PNECs are available and risk evaluation was only possible for 4 of the 10 beta blockers studied: acebutolol, atenolol, metoprolol, and propranolol. Only propranolol presented a ratio near or above 1, showing a possible environmental risk for 4 receiving waters out of 15.     

植物床人工湿地处理养殖废水研究

为研究风车草和美人蕉植物床人工湿地处理养殖废水效果,建立了4级波式流人工湿地。结果表明,SS、COD、NH+4-N、TN和TP的去除率分别达到了76％、77％、78％、77％和72％,美人蕉生物量和氮磷含量都要高于风车草,植物组织中氮磷分布为叶＞根＞茎。重金属在植物中的含量为Zn＞Pb＞Cu＞Ni＞Cr,其中Zn、Pb...     

垃圾渗滤液的加载磁絮凝预处理工艺研究

垃圾渗滤液是一种成分复杂多变的高浓度难处理有机废水。采用加载磁絮凝技术对垃圾渗滤液进行预处理,以提高其可生化性,便于后续生化处理的进行。研究了适宜的磁载体种类、凝聚剂和絮凝剂的加入量,以及不同pH值和药剂投加顺序的影响,并进行了磁絮凝与常规絮凝工艺的对比实验。得到的最优组合工艺为：PAC投加量5.5 g/L,磁载体投加...     

An empirical investigation of construction and demolition waste generation rates in Shenzhen city, South China

The construction and demolition waste generation rates (C&D WGRs) is an important factor in decision-making and management of material waste in any construction site. The present study investigated WGRs by conducting on-site waste sorting and weighing in four ongoing construction projects in Shenzhen city of South China. The results revealed that WGRs ranged from 3.275 to 8.791 kg/m² and miscellaneous waste, timber for formwork and falsework, and concrete were the three largest components amongst the generated waste. Based on the WGRs derived from the research, the paper also discussed the main causes of waste in the construction industry and attempted to connect waste generation with specific construction practices. It was recommended that measures mainly including performing waste sorting at source, employing skilful workers, uploading and storing materials properly, promoting waste management capacity, replacing current timber formwork with metal formwork and launching an incentive reward program to encourage waste reduction could be potential solutions to reducing current WGRs in Shenzhen. Although these results were derived from a relatively small sample and so cannot justifiably be generalized, they do however add to the body of knowledge that is currently available for understanding the status of the art of C&D waste management in China.     

Persistent organic pollutant emissions from medical waste incinerators in China

The huge amount of medical waste (MW) has caused a tough challenge to environmental protection in China because of its serious infectious potential. At present, incineration is the most common technology for MW disposal. Unfortunately, the medical waste incinerator (MWI) is considered one of the major sources of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). This study was conducted to investigate the generation and the components of MW; the fingerprint of PCDD/Fs in MWI; and PCDD/F, polychlorinated biphenyl (PCB) and hexachlorobenzene concentrations in residue ash. The estimated annual production of MW was estimated to be 0.97 million tons in China in 2008; in addition, plastic and rubber accounted for 24.5% of MW contents. PCDD/F emissions from MWI could be divided into two main groups according their fingerprints, and the ratio of PCDFs/PCDDs was mostly over 1.5, with a mean value of 3.43. The toxic equivalent of PCDD/Fs was over 30 times that of the value of PCBs in the residue ash, and PCDD/F contents in fly ash accounted for approximately 67% of the total output of PCDD/Fs, which was in line with the UNEP default emission factors for MWI (class 3, 63.7%).     

Trace level determination of selected organophosphorus pesticides and their degradation products in environmental air samples by liquid chromatography-positive ion electrospray tandem mass spectrometry

This paper describes a new analytical method for determination of organophosphorus pesticides (OPs) along with their degradation products involving liquid chromatography (LC) positive ion electrospray (ESI+) tandem mass spectrometry (MS-MS) with selective reaction monitoring (SRM). Chromatography was performed on a Gemini C6-Phenyl (150 mmx2.0 mm, 3 microm) with a gradient elution using water-methanol with 0.1% formic acid, 2 mM ammonium acetate mobile phase at a flow rate of 0.2 mL min(-1). The LC separation and MS/MS operating conditions were optimized with a total analysis time less than 40 minutes. Method detection limits of 0.1-5 microg L(-1) for selected organophosphorus pesticides (OP), OP oxon degradation products, and other degradation products: 3,5,6-trichloro-2-pyridinol (TCP); 2-isopropyl-6-methyl-4-pyrimidol (IMP); and diethyl phosphate (DEP). Some OPs such as fenchlorphos are less sensitive (MDL 30 microg L(-1)). Calibration curves were linear with coefficients of correlation better than 0.995. A three-point identification approach was adopted with area from first selective reaction monitoring (SRM) transition used for quantitative analysis, while a second SRM transition along with the ratio of areas obtained from the first to second transition are used for confirmation with sample tolerance established by the relative standard deviation of the ratio obtained from standards. This new method permitted the first known detection of OP oxon degradation products including chlorpyrifos oxon at Bratt's Lake, SK and diazinon oxon and malathion oxon at Abbotsford, BC in atmospheric samples. Atmospheric detection limits typically ranged from 0.2-10 pg m(-3).     

基于尖点突变的人群拥挤模型研究

近年来的统计分析表明,人群拥挤踩踏事故逐步上升为大型公共聚集场所的主要人为事故灾害类型之一。为了防止这类事故带来的危害,需要从理论高度开展对人群拥挤踩踏事故的承载体人群的运行系统的研究。国内外关于人群拥挤事故的研究方法很多,但至今还未找到较为完善、科学和经济的方法。因此提出将尖点突变理论引入到人群拥挤模型中,建立人群拥挤的尖点突变模型。实证分析表明,用突变模型得出的结论与数据拟合得出的结果大体一致,这说明突变理论应用于此领域是可行的。     

2009年中国大陆地震灾害损失述评

在列出2009年中国5.0级以上地震目录的基础上,结合年度有关省(自治区、直辖市)地震局的地震灾害评估资料,总结出2009年中国大陆地震灾害的主要数据和特性。最后对自1990年以来中国大陆地震灾害的相关数据进行了简要的比较。