气氛含氧量对DDT热处理特性的影响

滴滴涕属于有机氯农药,其所含成分DDTs在环境中难以降解,并具有生物毒性。利用高温管式炉研究气氛中含氧量对滴滴涕热处理特性的影响,为研发废弃滴滴涕高温热处理技术提供理论依据。实验结果表明,在600℃时,滴滴涕去除率最高为含氧量21%时的70.48%;在900℃条件下,当含氧量为21%时DDT去除率≥99%;在1 200℃条件下,当含氧量≥12%时DDT去除率≥99.9%。在滴滴涕热处理残渣中,o,p’-DDT占DDTs总量的比例在3个温度段中都随含氧量的增加而增长,DDT则都随含氧量增加而减少,且上述变化随温度升高而幅度加大。在尾气中,p,p’-DDE占DDTs总量的比例在3个温度段中都随含氧量增加而递增,在1 200℃条件下尤为明显。     

Rate of hexabromocyclododecane decomposition and production of brominated polycyclic aromatic hydrocarbons during combustion in a pilot-scale incinerator

Here, we examined the incineration of extruded polystyrene containing hexabromocyclododecane(HBCD) in a pilot-scale incinerator under various combustion temperatures(800–950℃) and flue gas residence times(2–8 sec). Rates of HBCD decomposition ranged from 99.996%(800℃, 2 sec) to 99.9999%(950℃, 8 sec); the decomposition of HBCD, except during the initial stage of combustion(flue gas residence time 2 sec), followed a pseudo-first-order kinetics model. An Arrhenius plot revealed that the activation energy and frequency factor of the decomposition of HBCD by combustion were 14.2 kJ/mol and 1.69 sec~(-1),respectively. During combustion, 11 brominated polycyclic aromatic hydrocarbons(BrPAHs)were detected as unintentional by-products. Of the 11 BrPAHs detected, 2-bromoanthracene and 1-bromopyrene were detected at the highest concentrations. The mutagenic and carcinogenic BrPAHs 1,5-dibromoanthracene and 1-bromopyrene were most frequently detected in the flue gases analyzed. The total concentration of BrPAHs exponentially increased(range,87.8–2,040,000 ng/m~3) with increasing flue gas residence time. Results from a qualitative analysis using gas chromatography/high-resolution mass spectrometry suggest that bromofluorene and bromopyrene(or fluoranthene) congeners were also produced during the combustion.     

鸟类对持久性有机污染物的定向传输作用研究进展

传统意义上认为,持久性有机污染物（POPs）的传输途径主要有两种形式,一种是通过挥发之后进入大气,然后通过长距离大气传输、蚱蜢效应、高山冷凝效应等方式进行传输;另一种是进入水体中,通过水流的搬运作用传输,从而进入湖泊、河流生态系统,甚至可以通过洋流的长距离输送到达北极等高纬地区．另外,海鸟、候鸟和留鸟可以对POPs进行...     

POPs废物处置技术筛选研究

采用层次分析法对国际上较为成熟的9种POPs废物处置技术进行综合评价,筛选了适合我国POPs废物处置的技术。从经济指标、环境指标和技术指标3个影响因素建立递阶层次结构模型,每个指标又细分为若干个子准则。根据模型及评价指标体系设计专家咨询表,发放给POPs相关领域的专家进行打分。采用matlab对评价结果进行数值分析,得...     

西溪湿地底泥质量现状与生态风险初步评价

为了解西溪湿地底泥质量现状,2012年9月采集保护区内不同干扰类型的底泥样本,测试了底泥中重金属和POPs中PCBs、OCPs和PAHs的含量,并对湿地底泥污染进行了生态风险初步评价。结果表明,底泥中未检出PCBs和OCPs,但检测出14种EPA优控PAHs,总PAHs的浓度范围为115.9～217.8 ng·g^-1,低于潜在生态风险的效应区间低值ERL,其中列入中国＂水中优先控制污染黑名单＂的7种PAHs均有检出并且其总量占∑PAHs 1/2左右（平均为50.08%）;底泥中8种重金属含量平均值低于《土壤环境质量标准》（GB 15618—1995）的二级标准,但Hg、Zn、Pb、Ni含量在多个位点已超过一级标准;分别采用土壤背景值和国家一级标准为参比值对湿地底泥中重金属进行单因子污染风险指数评价,发现分别有7种和4种元素的污染指数大于1;综合分析不同干扰类型的底泥质量,发现底泥疏浚能有效降低有机质含量、全氮和PAHs含量,但对全磷、重金属含量则无明显效果,封闭水体的干塘措施能显著减少污泥量和有机物含量。研究结果表明,西溪湿地底泥中高环PAHs和重金属污染水平可能对西溪湿地生物具有潜在的生物毒性作用及不利的生态影响效应,其疏浚底泥农用则无生态风险。     

Determination of PCDDs,PCDFs, PCBs and HCB emissions from the metallurgical sector in Poland

Background The aim of the project was to measure the actual emissions of PCDD/F, PCBs and HCB from 20 selected metallurgical installations in Poland, in order to update the national inventory of dioxin emission from metallurgical industry for developing a strategy for dioxins and furans emission abatement from the subject facilities (UNEP 2005). Methods Sampling methodology used in this work was developed at the Cracow University of Technology because of the complexity of simultaneous sampling and determining PCDFs, PCDDs, PCB and HCB. For the determination a GC-MS/MS system was used. Results and Discussion Results from the work indicate that the highest dioxins and PCB concentrations were recorded for iron ore sintering plants at 1.10–1.32 ng total¹ TEQ/Nm³ followed by aluminium scrap melting at 0.03–0.66 ng total TEQ/Nm³. The highest HCB concentrations at 613–1491 ng/Nm³ were also recorded for iron ore sintering plants, whereas at aluminium plants the HCB concentrations were in the range of only 10.1–22.7 ng/Nm³. Conclusions The above investigations indicate that secondary aluminium production is the most significant dioxins source, if calculated as emission factor values. However, iron ore sintering plants are operating at much higher production capacity, causing this process to become the major source of dioxins, PCB and HCB pollution to the atmosphere in Poland. Recommendations and Perspectives Based on the performed tests and the environmental reviews of selected plants several recommendations were formulated for the reduction of generation or of emission of these pollutants from iron ore sintering plants, electric arc furnace steel production processes, hot-blast furnace operations, secondary aluminium smelting and primary zinc production from zinc cathodes.     

环境激素的种类及危害分析

环境激素（环境荷尔蒙和环境内分泌）干扰物质是一类具有高稳定性、难生物降解的持久性有机化合物,因其引起的环境污染问题受到广泛关注。本文系统地分析了环境激素类干扰物质的来源、种类及与生物体作用机制,并讨论了它们进入人体的途径以及对生物和人类的危害,通过调查国内环境激素污染问题,指出环境激素污染存在的广泛性,需要引起政府部门高度重视,进一步加强防治环境激素污染工作力度。     

对二氯苯生产中的多氯联苯副产物排放与生成机制研究

对国内某化工企业一系列对二氯苯样品和日本某企业对二氯苯样品的PCBs副产物的含量和生成机制进行了研究.在该企业对二氯苯样品检测到了62～781 ng/g的PCBs,WHO-TEQ最高达到了0.24 pg/g,在日本样品中PCBs总量也达到了881 ng/g,说明PCBs副产物在对二氯苯生产中是一个比较普遍的现象.在对二氯苯样品中,PCB31是主要的PCBs单体,最高占到了PCBs总量的98.5%.对二氯苯样品中都是TrCBs含量最高,其次是TeCBs和DiCBs以及PeCBs;而氯苯样品中则是MoCBs含量最高,占到了PCBs总量的73.5%.本研究还对各主要PCBs化合物的生成机制进行了探索,发现多氯苯缩合生成PCBs的过程受到多氯苯的浓度和氯对苯环的定位影响,并得到了试验的证实.     

杀虫剂类POPs废物及污染场地治理共同责任研究

杀虫剂类POPs废物的环境无害化处置及其污染场地的治理是我国履行POPs公约的国家行动计划(NIP)的重要内容。我国POPs废物产生的责任主体主要是历史上的企业,企业经过了很大的变革,因而产生的POPs废物及其污染场地不同于现有工业企业产生的危险废物,需要根据历史、现状以及未来发展的特点建立新的责任制度,确立治理责任,落实治理资金。从我国杀虫剂类POPs废物和污染场地的现状调研出发,分析国内外相关法律规定中责任分担制度及原则,提出建立我国杀虫剂类POPs废物及其污染场地治理的"共同责任制度",为POPs废物的环境管理提供理论支持。     

Concentrations of persistent organic pollutants and organic matter characteristics as river sediment quality indices

Selected persistent organic pollutants – polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and organochlorine pesticides – were determined in sediments, soils, and crops from the Asopos River area, Greece. The river has been receiving industrial effluents for the last 40 years and has been recently found to be polluted with metals. Sediments were collected in the dry (May) and wet (February) season. Agricultural soils and cultivated crops were sampled from adjacent fields. Polychlorinated biphenyls were below the limit of detection in all samples. In one tomato and two soil samples, DDT and DDE were found. Polycyclic aromatic hydrocarbons were observed in 5% of the sediments and in concentrations ranging from 4 to 57 μg kg^?1 dry weight, quite below sediment quality guidelines. Diagnostic ratios of polycyclic aromatic hydrocarbons indicated a strong influence of petrogenic point discharges. In the sediments, silicate minerals dominate over carbonates and the organic carbon content ranges from 0.4% to 3.5%, more than 70% being of natural origin. Compared to other rivers worldwide, the Asopos River was found to be not contaminated with persistent organic pollutants. Point loadings of organic pollutants were evident but continuous discharge is not occurring throughout the river basin.