Advanced treatment of dyeing wastewater towards reuse by the combined Fenton oxidation and membrane bioreactor process

The performance of combined Fenton oxidation and membrane bioreactor (MBR) process for the advanced treatment of an effluent from an integrated dyeing wastewater treatment plant was evaluated. The experimental results revealed that under the optimum Fenton oxidation conditions (initial pH 5, H 2 O 2 dosage 17 mmol/L, and Fe 2+ 1.7 mmol/L) the average total organic carbon (TOC) and color removal ratios were 39.3% and 69.5% after 35 min of reaction, respectively. Results from Zahn-Wallens Test also represented that Fenton process was effective to enhance the biodegradability of the test wastewater. As for the further purification of MBR process, TOC removal capacity was examined at different hydraulic retention times (HRT) of 10, 18 and 25 hr. Under the optimum HRT of 18 hr, the average TOC concentration and color of the final MBR effluent were 16.8 mg/L and 2 dilution time, respectively. The sludge yield coefficient was 0.13 g MLSS/g TOC and TOC degradation rate was 0.078 kg TOC/(m 3 ·day). The final effluent of MBR can meet the reuse criteria of urban recycling water-water quality standard for miscellaneous water consumption GBT18920-2002.     

海河流域14条河流表层沉积物中多溴联苯醚的分布特征

海河流域是我国受人类活动扰动强度最大的地区,为了解多溴联苯醚（PBDEs）在该流域的污染现状与分布特征,通过采集14条主要河流的48个表层沉积物样品,采用高分辨的GC-MS/MS技术对干燥后的沉积物中27种PBDEs进行分析.结果发现沉积物中PBDEs的平均含量范围为0.06～2.10 ng·g^-1;其中徒骇河沉积物...     

中国东北主要河流沉积物中多溴二苯醚的含量状况及生态风险分析

为揭示多溴二苯醚(PBDEs)在东北主要河流流域内的污染现状,通过采集该地区流域内表层沉积物样品,采用GC-NCIMS技术对沉积物中41种PBDEs同类物进行分析.结果发现沉积物中BDE209含量低于检出限,其它40种PBDEs同类物总含量(不包含BDE209)范围(干重)为0.91~17.67 ng·g-1.其中第二松花江吉林市上游和下游沉积物样品中PBDEs的检出含量最高,分别为15.86 ng·g-1、17.67 ng·g-1,以BDE207和BDE47为主,分别占PBDEs总量的86.5%和76.6%;其它河流沉积物中各同族体含量差异并不明显.实验结果与国内外最近的文献报道值相比较,再结合生态风险分析显示,东北主要河流沉积物中PBDEs的含量处于低污染水平,目前不存在生态风险.     

多溴联苯醚在电子废弃物拆卸地沉积物中的垂直分布

采用气相色谱质谱联用仪对采自清远电子废弃物拆卸地水库钻孔沉积物中的多溴联苯(polybrominated diphenyl ethers,PBDEs)进行了分析,调查其在沉积物中的垂直分布.结果表明,PBDEs在所有的样品中均检出,含量为0.43～141 ng/g,平均为9.26 ng/g.PBDEs在下层(16 cm以下)沉积物中含量较低、变化很小(0.43～2.30 ng/g),但在上层沉积物中含量明显增加(2.90～141 ng/g),反映了当地电子废弃物拆卸活动的影响;3种工业源的PBDEs,即五溴、八溴和十溴PBDEs,表现出相似的垂向分布趋势,说明其来源的一致性.其中,十溴PBDEs是最主要的PBDEs,平均占所有PBDEs的79.6%,其次是五溴PBDEs(14.7%),而八溴PBDEs所占比例最低(5.69%).3种PBDEs的组成模式显示,它们与相应的工业品PBDEs组成都有一定差异,可能因其降解行为不同所致.一些PBDE的同族体组成在沉积钻孔的垂直变化也进一步说明高溴代PBDE在沉积物的埋藏期间可能发生了降解,虽然还需要进一步研究证实.     

府河和白洋淀沉积物中DDTs的分布特征和风险评估

利用气相色谱-质谱(GC-MS)检测了府河和白洋淀共计19个表层沉积物样品中的w(DDTs)及其分布特征. 结果表明,w(DDTs)为1.74～51.33 ng/g (以干质量计),平均值为11.01 ng/g,其分布特征呈现从府河到白洋淀逐渐递减的趋势. 与国内其他地区沉积物相比,府河和白洋淀地区DDTs的污染处于中等偏低的水平. 在所有沉积物样品中,p,p′-DDT所占比例较大,是最主要的异构体. 大部分样品中w(DDD)/w(DDE)大于1,而w(DDT)/w(DDE+DDD)小于1,说明研究区DDT处于厌氧环境条件,且没有新的DDT输入. 该地区DDTs主要来源于农田土壤侵蚀及工业废水排放. 潜在风险评估表明,府河和白洋淀的表层沉积物中DDTs对周围环境具有一定的影响,应引起相关部门的重视.      

Organochlorine compounds and polycyclic aromatic hydrocarbons in surface sediment from Baiyangdian Lake, North China： Concentrations, sources profiles and potential risk

Organochlorine pesticides(OCPs),polychlorinated biphenyls(PCBs),and polycyclic aromatic hydrocarbons(PAHs) were determined in nineteen surface sediment samples collected from Baiyangdian Lake and its inflowing river(Fuhe River) in North China.Total concentrations of OCPs,PCBs and PAHs in sediments ranged from 5.4 to 707.6 ng/g,2.3 to 197.8 ng/g,and 101.3 to 6360.5 ng/g,respectively.The levels of contaminants in Fuhe River were significantly higher than those in Baiyandian Lake.For hexachlorocyclohexane(HCHs) and dichlorodiphenytrichloroethanes(DDTs),α-HCH and p,p-DDT were predominant isomers;while for PCBs,PCB 28/31,PCB 40/103,PCB 60,PCB 101,and PCB 118 were predominant congeners.Possible sources derived from historical usage for OCPs and incomplete combustion fuel,wood,and coal and exhaustion of boats or cars for PAHs.Risk assessment of sediment indicated that sediments in Fuhe River were likely to pose potential biological adverse impact.     

有机氯农药和多溴联苯醚在白洋淀鸭子组织中分布特征研究

利用气相色谱-质谱(GC/MS)方法定量分析了白洋淀鸭子肌肉、肝脏、脑组织中HCHs、DDTs和PBDEs的分布特征.结果表明,3种组织中HCHs和DDTs的含量范围分别为0.9～5.0 ng/g(以湿重计,下同)和0.3～2.8 ng/g,而PBDEs的含量范围是0.03～0.65 ng/g.统计分析鸭子不同组织中持久性卤代烃的含量差异,结果显示,DDTs和PBDEs的含量水平有较大差异(p0.05);而HCHs在3种组织中的含量差异不明显(p0.05).肝脏中DDTs和PBDEs的平均含量较高,分别为2.3和0.37 ng/g.在HCHs和DDTs同系物(代谢物)组成中,β-HCH在肝脏和脑组织中占主要地位,p,p′-DDE是DDTs的主要代谢产物;在PBDEs同系物中,BDE47和BDE99是鸭子组织中主要的组成部分.鸭子不同组织中HCHs、DDTs和PBDEs的组成模式反映了白洋淀仍然受到历史残留的有机氯农药污染;同时,来自白洋淀上游的工业污染很可能输入新型持久性有机污染物(PBDEs).     

Occurrence and bioaccumulation of polybrominated diphenyl ethers in sediments and paddy ecosystems of Liaohe River Basin, northeast China

Concentrations of 16 polybrominated diphenyl ether(PBDE) congeners were measured in river sediments, paddy soils and three species of paddy-field organisms(crab, loach and carp) collected from the Liaohe River Basin, northeastern China. The total contents of PBDEs(∑_(16)PBDEs) in sediments and paddy soils were in the ranges of 273.4–3246.3 pg/g dry weight(dw), and 192.1–1783.8 pg/g dw, respectively. BDE 209 was the dominant congener both in sediments and paddy soils. The concentrations of ∑_(16)PBDEs in sediments were significantly higher than those in the adjacent paddy soils, indicating a potential transport of PBDEs from river to paddy ecosystems via river water irrigation. The biota–soil accumulation factor(BSAF) was calculated as the ratio between the lipid-normalized concentration in paddyfield organisms and the total organic carbon-normalized concentration in paddy soil. The average BSAF values of ∑15PBDEs followed the sequence of crab(3.6) loach(3.3) carp(2.1). BDE 154 had the highest BSAF value, and a parabolic trend between BSAF values of individual PBDE congeners and their log KOWvalues was observed. In view of the fact that crab had the larger BSAF value and higher lipid content, the ecological risk and health risk for crab cultivation in paddy fields should be of particular concern.     

成渝经济区河流表层沉积物中多溴联苯醚的分布特征

在成渝经济区内采集了19个表层沉积物样品,采用GC/MS方法对其中的PBDEs(Polybrominated Diphenyl Ethers,多溴联苯醚)进行了检测. 结果表明,沉积物中w(ΣPBDEs)(ΣPBDEs包括BDE-1,BDE-15,BDE-17,BDE-28,BDE-47,BDE-66,BDE-71,BDE-85,BDE-99,BDE-100,BDE-126,BDE-138,BDE-153,BDE-154,BDE-166,BDE-181,BDE-183和BDE-190)为0.20～6.45 ng/g,w(BDE-209)为0.44～6.29 ng/g. 与其他地区相比,成渝经济区内PBDEs的污染水平相对较低, 大部分样品中的PBDEs以BDE-209为主,说明成渝经济区河流沉积物中的PBDEs主要来自十溴联苯醚; 但PBDEs的组成特征显示,彭山岷江大桥沉积物中的PBDEs主要来自五溴联苯醚,而官渡沉积物中的PBDEs主要来自八溴联苯醚. 此外,一些以往工作较少关注的PBDEs单体,如BDE-1,BDE-15,BDE-181和BDE-190等,不但在沉积物中的检出率较高(均高于70%),而且有的含量也相对较高.      

Polybrominated diphenyl ethers in soil from three typical industrial areas in Beijing, China

Areas containing industrial facilities belonging to three different typical industries that may cause pollution by polybrominated diphenyl ethers （PBDEs） in Beijing, China were investigated. Specifically, the areas contained a solid waste incineration plant, a chemical factory, and a heat and power plant. Investigation of the pollution status of PBDEs in the surface soil from areas around these industries revealed the highest concentration of 42 PBDE congeners （118 ng/g, dry mass） at the solid waste incineration plant. In the other two plants, the highest concentrations were both 26 ng/g （dry mass）. Among the PBDE homologues, the PBDE contamination at all sites showed similar congener compositions, with BDE 209 being the dominant congener. Our findings established the first contamination status of three typical industrial areas in Beijing. Furthermore, the total concentrations of 42 PBDE congeners tended to decrease as the distance from the investigated plants increased. Overall, these plants were identified as potential pollution sources of PBDEs in Beijing. Moreover, Pearson correlation analysis revealed that the major PBDE source in Beijing may be associated with the technical deca-BDE and penta-BDE mixture. Based on the data obtained in this preliminary investigation, further study of the potential of these sources to emit PBDEs in Beijing is warranted.     

珠江三角洲及南海北部海域表层沉积物中多溴联苯醚的分布特征

自珠江三角洲和南海北部海域采集了66个表层沉积物样品,以研究该区域中PBDEs的含量、分布、来源和在环境中的迁移.研究结果表明,东江和珠江是PBDEs的高污染区,含量为12.7～7361ng·g-1,其中BDE209平均含量为1199ng·g-1,是目前世界上已报道沉积物中含量最高的区域之一.在几乎所有被分析的样品中BDE209都是最主要的同系物.东江和珠江的PBDEs主要来自东莞和广州的本地排放,而西江的PBDEs主要通过大气的传播输入.另一个高污染区澳门水域被验证是珠江三角洲水体环境中有机污染物的“汇”.     

Characterization, treatment and releases of PBDEs and PAHs in a typical municipal sewage treatment plant situated beside an urban river, East China

Characterization, treatment and releases of eight polybrominated diphenyl ethers (PBDEs) congeners and sixteen polycyclic aromatic hydrocarbons (PAHs) in wastewater were evaluated along the treatment processes of a typical secondary treatment municipal sewage treatment plant (STP) (in Hefei City) situated the beside Nanfei River, East China. The findings showed that the average concentrations of the total PBDEs in raw wastewater and treated effluent were 188.578 and 36.884 ng/L respectively. Brominated diphenyl ether (BDE) 209 congener, the predominant PBDE in the STP and Nanfei River, could be related to the discharge of car-industry-derived wastes. For PAHs, the average concentrations in raw wastewater and treated effluent were 5758.8 and 2240.4 ng/L respectively, with naphthalene, benzo[a]pyrene and indeno[1,2,3-c,d]pyrene being detected at the highest concentrations. PAHs mainly originate from the combustion of biomass/coal and petroleum. The STP reduced about 80% of the PBDEs and 61% of the PAHs, which were eliminated mainly by sedimentation processes. The removal rates of PBDEs/PAHs increased with the increase of their solid-water partitioning coefficients. Accordingly, the STP's effluent, containing some PBDE congeners (e.g., BDE 47, 99 and 209, etc.) and low-molecular-weight PAHs, could be an important contributor of these contaminants' input to Nanfei River. It resulted in a significant increase of PBDE/PAH concentrations and PAH toxicological risk in the river water downstream. About 4.040 kg/yr of PBDEs and 245.324 kg/yr of PAHs could be released into the Nanfei River. The current conventional wastewater treatment processes should be improved to remove the relatively low-molecular-weight PBDEs/PAHs more effectively.     

Levels and distribution of brominated flame retardants in the soil of Harbin in China

This study reports the presence of brominated flame retardants in the topsoil in and around Harbin, a city in northeastern China. Samples of soil were collected from 17 locations in 2006, and the levels of 9 polybrominated diphenylethers (PBDEs 17, 28, 47, 66, 99, 100, 153, 154, and 183) ranged from 2.45 to 55.9 pg/g dry weight (dw) with a mean of 26.3 pg/g dw. These levels are very low comparing with those for some cities in Europe and USA. BDE 209 and hexabromocyclododecane were the two dominant congeners, with mean concentrations of 520 pg/g dw and 1750 pg/g dw, respectively. The concentrations of the total nine PBDE congeners clearly decreased from urban areas to background, but the compositions of individual congeners di ered. Proportions of heavier congeners decreased while those of lighter congeners increased, along urban-rural-background transect, providing evidence for an urban fractionation e ect. Correlation analysis indicated similar sources for PBDEs, hexabromocyclododecane, and 1,2-bis(2,4,6-tribromophenoxy)-ethane from urban areas but pentabromoethylbenzene was probably present due to long-range atmospheric transport. Principal component analysis was used to determine the characteristics of the relationships among these brominated flame retardants in the field.     

电子废物拆解区河流沉积物中多溴二苯醚的污染水平、分布及来源

用GC-NCI-MS分析法测定了路桥河流表层沉积物中41种多溴二苯醚同类物的含量. 目的是了解该地区沉积物中PBDEs的污染水平、空间分布特征和来源. 结果表明,所有沉积物样品中₄₀PBDEs(不包括BDE209)的含量为0.177～161 ng·g^-1,平均值为22.5 ng·g^-1, BDE209的含量为0.36～958 ng·g^-1,平均值为148 ng·g^-1. 同族体组成特征表明多数样品中十溴二苯醚(BDE209)是最主要的同族体,占38.4%～96.0%, 平均值为74.4%,九溴PBDEs和七溴PBDEs次之, 分别占3.3%～25.8%和0.01%～14.1%. PBDEs同类物之间呈显著性相关,表明大多数PBDEs同类物有相似的输入途径.同族体组成和聚类分析表明,所有采样点均受到deca-BDE工业品的污染,另有一些采样点除受到deca-BDE工业品的污染外, octa-BDE工业品也有一定的贡献. 与国内外其它研究相比,研究区域内沉积物中的PBDEs污染处于中低水平,但个别样点受点源污染影响较大,值得关注.     

工业园及电子垃圾区大气中的溴代阻燃剂(BFRs)

对广州市主要的工业园以及清远电子垃圾回收拆解园周边空气中溴代阻燃剂（BFRs）进行了分析.结果表明,两地区大气中均以多溴联苯醚（PBDEs）和十溴二苯乙烷（DBDPE）为主（城市地区占比分别为30.0%和68.0%,电子垃圾区分别为74.5%和22.8%）,其中PBDEs在城市地区和电子垃圾区的浓度中值分别为184和411pg/m³;DBDPE则分别为414和193pg/m³.在城市地区,PBDEs的浓度高值多出现在与机械、电子、装饰材料和汽车制造业有关的工业园,新型阻燃剂DBDPE高浓度则多在与机械和电子产品制造业相关的大气中,而1,2-二（2,4,6-三溴苯氧基）乙烷（BTBPE）可能受当地面源污染影响较大.城市地区低分子量的PBDEs的组成波动较大,与五溴联苯醚的禁用（直接排放减少）和来源复杂有关;而电子垃圾区低分子量PBDEs组成稳定,气-固相分配更接近平衡,说明来源较为单一.通过模型估算,城市地区的21个工业园每年约向空气中释放48.0kg的BDE209与163kg的DBDPE,4个电子垃圾拆解园每年约释放31.8kg的PBDEs与12.0kg的DBDPE.     

长江中游沉积物中多溴联苯醚的污染特征及风险评价

多溴联苯醚(PBDEs)具有高毒性和生物累积性,进入水体后易与有机质相结合,成为PBDEs污染物的重要归宿,对人类健康和水生生态系统造成潜在的危险.为揭示多溴联苯醚(PBDEs)在长江中游流域的污染现状,通过采集该地区流域内13个表层沉积物样品,采用高分辨气相色谱/高分辨质谱法(HRGC/HRMS)对沉积物中9种PBDEs同类物进行分析.结果表明该地区沉积物中9种PBDEs的含量范围(干重)约为46.1~326 pg·g~(-1),而BDE-99是其中最主要的贡献单体,平均贡献率约为51.6%;其次是BDE-47,约为19.6%.与国内外其他海域的研究相比,长江中游沉积物中PBDEs残留量处于较低水平.通过测定沉积物中总有机碳(TOC),研究结果发现PBDEs含量与TOC无明显的正相关关系.结合商值法对PBDEs的健康风险进行初步评估,结果表明,本研究中PBDEs对人体产生的健康风险较小.     

鄱阳湖三江口柱状沉积物有机氮同位素特征及其环境指示意义

通过对鄱阳湖三江口处柱状沉积物中δ15N、C/N比值、TOC和TN等含量的测定,分析了其有机质及氮素的来源.结果表明: 赣江、抚河、信江及鄱阳湖处柱状沉积物δ15N值变化范围分别为2.44‰~4.55‰、4.03‰~5.84‰、3.79‰~4.81‰及3.42‰~8.13‰.赣江南支其沉积有机质主要来源于土壤有机质;抚河整个柱状沉积物以自生有机物源为主;信江西支在12cm以下其沉积有机质主要受藻类及土壤有机质两种物源的影响,而12cm以上受外源影响比较小;鄱阳湖梅溪嘴表层2cm处沉积有机质来源以藻类为主,而中间6~3cm处主要来源于土壤有机质,7cm以下主要来源于藻类及土壤有机质.赣江南支、信江西支及鄱阳湖梅溪嘴沉积物氮素均主要来源人工合成肥料和土壤流失氮,而抚河主要来源于土壤流失氮.     

广州市室内尘土中多溴联苯醚的分布特点及来源

随机采集了广州市46个家庭和12个办公室内尘土样品,同时采集了17个室外尘土样品、2个电视机和2个电脑尘土样品并分析了室内尘土中多溴联苯醚(PBDEs)的含量、单体分布及来源.结果表明,家庭尘土中∑10PBDEs(BDE28,47,66,85,99,100,153,154,183,209之和)的含量为 564.3~9654ng/g,中值和均值分别为 2686,3407ng/g;办公室尘土中∑10PBDEs 的含量为 1737~4408ng/g,中值和均值分别为3133,3179ng/g.室内尘土中PBDEs的最主要单体为BDE209,分别占家庭尘土和办公室尘土∑10PBDEs的97.4%和99.0%.BDE47、99和183在室内尘土中含量也较高.大多数室内尘土中∑10PBDEs的含量高于室外,说明室内可能有重要的PBDEs释放源.室内尘土中PBDEs的主要工业品来源为十溴联苯醚,五溴联苯醚次之,八溴联苯醚较少.     

Occurrence of polybrominated diphenyl ethers in fish and shellfish downstream from electronic-waste recycling plants

We measured 39 polybrominated diphenyl ethers (PBDEs) in the muscle tissue of three species of fish (Sciaenops ocellatus, Sparus macrocephalus, and Lateolabrax japonicus) and four species of shellfish (Tegillarca granosa, Cyclina sinensis, Sinonovacula constricta, and Ostrea cucullata) that were collected downstream of electronic-waste recycling plants in Taizhou, China. A total of 24 PBDE congeners (PBDE24) in the samples were detected. The PPBDE24 (total PBDE) ranged from 545.4 to 1688.7 ng/kg ww (wet weight). The mean PPBDE24 concentration was 1382.6 ng/kg ww in fish and 858.1 ng/kg ww in shellfish. The lower brominated congeners were detected at relatively high concentrations in all species. The penta-products, produced from e-waste, were found at relatively low levels. A principal component analysis suggested a significant correlation among di-, tri-, tetra-, and hepta-BDEs for the three species of fish. Similarly, we found a significant correlation between mono- and tri-BDEs in the shellfish. Our results suggested that the processes of PBDE metabolism and elimination were similar in both fish and shellfish. In addition, the primary source of PBDEs appeared to be from the debromination of high brominated PBDEs.     

纳米零价铁降解水中多溴联苯醚(PBDEs)及降解途径研究

纳米零价铁(nZVI)法是多溴联苯醚(polybrominated biphenyl ethers,PBDEs)脱溴的有效方法.其反应动力学与途径对阐明PBDEs降解机制具有重要意义.本研究采用液相还原法制备的nZVI,在含有表面活性剂聚乙二醇辛基苯基醚(Triton X-100)的条件下,46 h内完全降解商用八溴联苯醚(octa-BDE)混合物中高溴代物质(7~9个溴代的同系物),其降解过程符合类一级反应动力学(pseudo-first-order)方程,平均降解速率常数(k)为0.106 h-1.本研究利用数量结构保留关系(quantatitivestructure retention relationship,QSRR)模型建立了在缺乏全系标准样品的情况下PBDEs降解产物的有效分析方法.通过混标中39种PBDEs各标准物在气相色谱中的保留时间,再以BDE47和BDE183的平均保留时间归一化后得到每种标准物的相对保留时间(relative retention time,RRT),再将数据库中的相对保留时间指数(relative retention time index,RRTI)与实验测得的相对保留时间拟合,得到QSRR模型.利用该模型对octa-BDE降解产物进行定性分析,推导得出nZVI对octa-BDE的还原降解途径.结果表明,nZVI对PBDEs的逐级脱溴过程中,间位的溴原子最容易被取代.