药品和个人护理用品(PPCPs)对环境的污染现状与研究进展

在过去的30多年中，有关有毒污染物的研究主要集中在工业化学物质和农药上。近5年多来，国外已经开始关注药品和个人护理用品（PPCPs）对环境的污染，但在我国还没有引起重视。国外的研究表明，合成麝香物质、显影剂、抗生素、雌激素、消炎止痛药、杀菌消毒剂等与人类生活密切相关的药品和个人护理用品在环境中普遍存在，但是其质量浓度通常非常低，多数情况下在ng/L～μg/L水平。粪便施肥和污水排放是PPCPs进入环境的主要途径。在常见的PPCPs中，抗生素和消炎止痛药在环境中检测出的频率最高，在地表水、地下水、饮用水、污泥、土壤等环境介质中，PPCPs在地表水中检测出的频率最高。目前关于PPCPs的研究主要集中在分析方法以及环境污染水平的调查，有关PPCPs在环境中的迁移转化规律，生态与健康风险以及PPCPs污染控制技术等方面的研究有待加强。     

某市水源水及净水厂中药品和个人护理品（PPCPs）的分布、含量和去除规律

随着检测技术的发展和检测水平的提升,水中痕量的PPCPs被不断发现,水源水以及饮用水中的痕量PPCPs亦被逐步重视起来。为了掌握珠三角某市饮用水系统中PPCPs的变化规律,采用固相萃取和超高压液相色谱-质谱联用技术调查了某市水源水、净水厂出厂水和管网水中目标PPCPs的分布和含量情况,同时研究了目标PPCPs在水厂中的去除规律。结果表明,在20个批次的样品中,该市水源1和水源2中分别检出7种和10种PPCPs。水源1中咖啡因的检出质量浓度最高,平均质量浓度为24.7ng·L^-1。水源2中红霉素的检出质量浓度最高,平均质量浓度为22.1ng·L^-1。在20个批次的样品中,常规处理工艺(水厂1、3和4)的出厂水分别检出3种、7种和7种PPCPs,深度处理工艺(水厂2)的出厂水中检出1种PPCPs。出厂水中PPCPs种类远少于水源水,浓度也明显下降。除水厂2以外,管网水中均有PPCPs检出,与出厂水相比,管网水中PPCPs种类和浓度也有所降低。常规处理工艺只对部分目标PPCPs有较好的去除效果,其中预氯化对PPCPs去除起重要作用;深度处理工艺对大...     

氧化型染发剂对沙蚕的毒性效应及对部分酶活性的影响

在实验室模拟条件下,研究了氧化型染发剂对双齿围沙蚕(Perinereis aibuhiteusis Grube)的急性毒性效应及不同暴露浓度(0、40、80、160、320mg·L-1)和暴露时间(0、4、6、8、10d)下对其体内乙酰胆碱酯酶(AChE)和超氧化物歧化酶(SOD)活性的影响.结果表明,1)暴露3d后氧化型染发剂对沙蚕的半数致死浓度(LC50)为1849.6mg·L-1;2)沙蚕体内AChE和SOD活性受到氧化型染发剂暴露浓度的显著影响:暴露3d后,随暴露浓度的升高(0～320mg·L-1),AChE和SOD活性均呈先被诱导后逐渐下降的变化趋势;3)沙蚕体内AChE和SOD活性也受到暴露时间的显著影响:40mg·L-1浓度下,随暴露时间的延长(0～10d),SOD活性呈先下降又缓慢上升的趋势,而AChE活性变化没有显著规律;4)通过比较发现,相对于AChE,SOD的活性变化更能反映氧化型染发剂对沙蚕的毒性作用.     

卡马西平及其衍生物的环境行为及其去除研究进展

药品和个人护理用品(PPCPs)是近年来出现的一类新型污染物,该类污染物浓度较低,但是结构复杂,具有较强的生物活性,其潜在危害不容忽视,因此日益受到人们关注.其中卡马西平(carbamazepine)作为一种典型的抗癫痫药物,是最有代表性的一种PPCPs物质.由于卡马西平的广泛使用,导致其大量排放到环境中.此外,人类服用卡马西平后由于体内代谢作用以及卡马西平母体在环境中的降解会产生多种衍生物,这些衍生物的毒性可能比母体化合物强,并且更难以降解,因此研究卡马西平及其衍生物的环境行为及其去除十分重要.本文结合当今的研究成果以及现有的处理技术,介绍了卡马西平及其衍生物的污染情况,综述了卡马西平及其衍生物在土壤中的迁移转化以及在环境中的降解,并对未来研究方向提出了展望.     

城镇污水循环活性污泥处理系统中典型新烟碱类杀虫剂污染特征及去除特性

采用固相萃取-高分辨液相色谱-串联质谱(SPE-HPLC-MS/MS)技术,研究了广东省中山市某城镇污水循环活性污泥处理系统中5种典型新烟碱类杀虫剂污染特征及去除特性.结果 表明,城镇污水循环活性污泥处理系统各工艺段均检测到新烟碱类杀虫剂残留(未检测到噻虫啉),且新烟碱类杀虫剂检出浓度随处理流程逐渐下降;其中缺氧运行阶...     

污水生物处理过程药品及个人护理品转化产物识别研究进展

药品及个人护理品(pharmaceuticals and personal care products,PPCPs)在污水生物处理过程会发生生物及化学转化从而生成转化产物,某些转化产物较母体化合物毒性更高.目前对PPCPs转化产物关注不够,转化产物识别方法不明确.本文介绍了污水中PPCPs转化产物的识别流程,系统阐述了...     

铁碳微电解降解磺胺甲恶唑和卡马西平

以两种典型人工合成有机物(磺胺甲恶唑和卡马西平)为主要研究对象,采用铁碳微电解法降解上述两种目标污染物,研究了铁碳质量比、反应时间、pH、铁投加量等因素对磺胺甲恶唑和卡马西平降解效果的影响.结果表明,pH=1,铁碳比为1∶1,铁投加量为80 g·L~(-1)时,磺胺甲恶唑的去除率最高,60 min几乎全部去除.pH=1,铁碳比为1∶4,铁投加量为80 g·L~(-1)时,卡马西平的去除率最高,60 min卡马西平去除率接近90%.在这过程中磺胺甲恶唑和卡马西平发生氧化还原反应,它们的氮被还原成氨氮.磺胺甲恶唑和卡马西平的降解符合假一级反应动力学.     

水力空化(HC)联合高级氧化技术去除典型手性药物的研究进展

普通药物中大部分是具有一对对映异构体手性结构的手性药物(CDs),且CDs作为一种新型微污染物在水体中被频繁发现.该药物因其种类和组成的不同,内部的对映异构体可能会表现出特异性,如体现在毒性、与蛋白质结合吸收以及在河流中自然衰减率等方面.而高级氧化法(AOPs),如空化(水力空化和声空化)、Fenton法和光催化法等技术手段,在去除CDs方面已表现出较大潜力.本研究基于对映体结构,全面梳理了CDs的性质、来源及对人类健康的影响,拟探究水环境中典型CDs的手性反转和药理学立体选择性特征,并归纳了水力空化方法联合AOP技术对萘普生、布洛芬等典型CDs去除效果特点,重点讨论了该方法作用机理与其利弊,探究最优适用条件,最终归纳出目前CDs分离分析技术的瓶颈及未来环境中CDs去除技术的研究趋势.     

Biological removal of selenate in saline wastewater by activated sludge under alternating anoxic/oxic conditions

Removal of selenate in saline wastewater by activated sludge was examined. Sequencing batch reactor was operated under alternating anoxic/oxic conditions. Above 97% removal of soluble selenium (Se) was achieved continuously. Major Se removal mechanism varied depending on the length of aeration period. Various Se-reducing bacteria likely contributed to coordinately to Se removal. Selenium (Se)-containing industrial wastewater is often coupled with notable salinity. However, limited studies have examined biological treatment of Se-containing wastewater under high salinity conditions. In this study, a sequencing batch reactor (SBR) inoculated with activated sludge was applied to treat selenate in synthetic saline wastewater (3% w/v NaCl) supplemented with lactate as the carbon source. Start-up of the SBR was performed with addition of 1–5 mM of selenate under oxygen-limiting conditions, which succeeded in removing more than 99% of the soluble Se. Then, the treatment of 1 mM Se with cycle duration of 3 days was carried out under alternating anoxic/oxic conditions by adding aeration period after oxygen-limiting period. Although the SBR maintained soluble Se removal of above 97%, considerable amount of solid Se remained in the effluent as suspended solids and total Se removal fluctuated between about 40 and 80%. Surprisingly, the mass balance calculation found a considerable decrease of Se accumulated in the SBR when the aeration period was prolonged to 7 h, indicating very efficient Se biovolatilization. Furthermore, microbial community analysis suggested that various Se-reducing bacteria coordinately contributed to the removal of Se in the SBR and main contributors varied depending on the operational conditions. This study will offer implications for practical biological treatment of selenium in saline wastewater.     

Enhancement of activated sludge performance on ammonium removal by clinoptilolite

This study evaluated the influence of clinoptilolite on the performance of activated sludge system shocked by high concentration of ammonium. The ammonium and chemical oxygen demand (COD) removal from the experimental reactor containing clinoptilolite and from the clinoptilolite-free control reactor was determined. The ammonium and COD removal was approximately 8 and 20% higher in the experimental reactor than in the control reactor, respectively. The removal increased with an increase in clinoptilolite concentration over the tested range up to 50?mg?L^?1. The presence of clinoptilolite resulted in the sludge flocs being more compacted with smoother surfaces and edges. Molecular biological analysis revealed that clinoptilolite increased the DNA diversity, richness, and evenness of sludge microbes. The enhanced-performance activated sludge previously treated with clinoptilolite was less influenced by the shock of ammonium than non-treated sludge in terms of the ammonium and COD removal. These results suggest that clinoptilolite enhanced the performance of activated sludge system in the removal of ammonium and COD. Amendment of activated sludge with natural zeolites may thus improve the efficiency of wastewater treatment.     

Combined treatment of phenolic wastewater by wet air oxidation and activated sludge

Wet air oxidation (WAO) is employed in this work for treating high concentration chemical wastewater containing phenol and/or phenolic compounds. Experimental results indicate that over 90% removal of phenol or phenolic compounds can be efficiently achieved in the WAO process. Despite of the high treatment efficiency of the WAO process, the treated wastewater, however, still retains relatively high chemical oxygen demand (COD) concentration and does not meet the safe discharge standard. Hence further treatment of the WAO treated wastewater by an aerobic biological treatment using acclimatized activated sludge is necessary. It is found in the present studies that the combined process, if appropriately operated, is capable of drastically reducing the COD concentration of the high concentration chemical wastewater to meet the safe discharge requirement. The operating conditions of the combined process are investigated to determine their respective effects on the overall treatment efficiency. The experimental data also indicate that the oxidation reaction can be represented by a first order kinetics in terms of the component or COD concentration. For both single component and multicomponent wastewaters, the WAO process was found to have different activation energy for oxidation below and above 200°C, suggesting possibly different reaction mechanisms between these temperature ranges. The experimental results provided in the present work can provide significant and practical information for optimizing the combined treatment method.     

焦化废水处理厂活性污泥对硫氰化物的降解机制

用分光光度法和离子色谱法,研究了A/A/O工艺焦化废水处理厂的进出水质和活性污泥对硫氰化物(SCN-)的降解机制.研究结果表明,SCN-主要在A/A/O工艺的好氧单元中降解去除;在常温(25℃)下活性污泥对SCN-降解的动力学过程符合米氏方程,Vmax为11.15 mg SCN-·(g-1MLSS)·h-1,Km为44.96 mg·L-1;15℃低温显著降低SCN-的降解速率;在15℃下,92.62 mg·L-1SCN-能在24 h内完全降解,其中的N和S元素相应地生成了NH3、NO-2和S2-等中间代谢产物,并最终转化为产物NO-3和SO2-4;N和S元素的转化率分别为94.32%和99.08%,基本符合物料守恒定律,说明SCN-中N和S元素在好氧池中可以彻底降解转化NO-3和SO2-4.这些结果对于了解好氧池的功能和提高焦化废水中的SCN-去除率具有重要意义.     

仿生植物附着微生物膜对污染水体氮素迁移转化效能分析

通过室外及室内控制试验,研究5种常见填料作为原材料制成的仿生植物对污染水体氮素的去除性能,结果表明,仿生植物原材料的差异将直接影响其附着生物膜特性,其附着生物膜量、硝化强度、反硝化强度以及硝化细菌、反硝化细菌均表现为：软性填料﹥组合填料﹥悬浮填料﹥立体弹性填料﹥半软性填料。水深对仿生植物附着生物膜亦有不同程度的影响,其中生物膜量随水深的增加并未表现出明显的分层效应,而生物膜硝化作用强度、硝化细菌随水深的增加逐渐降低,但生物膜反硝化作用强度、反硝化细菌则随水深的增加则呈现出逐渐增加的趋势。5种不同材质的仿生植物对水体TN、NH4＋-N、NO3--N具有较好的去除效果,去除率表现为：软性填料﹥组合填料﹥悬浮填料﹥立体弹性填料﹥半软性填料﹥对照系统。同时,仿生植物种植密度也影响其对水体氮素的去除效果,表现为CK〈7株·m-3〈13株·m-3〈20株·m-3,研究结果将为仿生植物的野外实际应用及我国城市重污染河道水质原位修复提供技术支持。     

Effect of mercury-contaminated wastewater on activated sludge suspended solids size distribution

The primal purpose of this research project is to examine the size distribution of the Suspended Solids (SS) of an activated sludge pilot plant, under different operational conditions and during the introduction of wastewater contaminated with mercury of different concentrations (10–100 µg/L Hg(NO₃)₂). While the experiment was being conducted, the most important parameters of the pilot plant (COD, TOC, MLSS, SS, NH₄, PO₄, total number of bacteria – coccoids and rods, pH, DO, T etc.) were measured; this fact led to the inference of conclusions that connect the distribution of the size of the SS with those parameters. The main conclusions of this research work are: (a) the important interaction of the removal ability of the organic loading of the plant and the size distribution of the SS at the aeration tank and the outlet of the plant and (b) the input of the mercury-contaminated wastewater at the plant affects the size distribution of the SS at the aeration tank. The second conclusion probably indicates a possible way that microorganisms of the aeration tank react to the introduction of mercury.     

糖类在城市污水生物处理系统中的去除机理

研究了厌氧、缺氧和好氧状态下淀粉在城市污水生物处理系统中水相和泥相中吸附和降解的动力学参数,建立了淀粉在厌氧、缺氧、好氧状态下的降解动力学模型,并对模型预测的结果进行了验证.结果表明,Fritz-Schlunder模型可以较好地描述糖类在厌氧、缺氧和好氧污泥上的吸附过程,吸附的大分子糖类迅速水解为低一级的高分子物质和小分子物质;厌氧降解速率系数K厌、缺氧的降解速率系数K缺与好氧的降解速率常数的比值分别为0.40和0.64;所建立的动力学模型能较好的预测出水糖类的浓度(相对误差<10%).     

熔盐法去除污泥焚烧灰中磷的效果及热动力学分析

利用碳还原剂和氯化钙熔盐药剂在1100℃下还原污泥焚烧灰中的磷酸盐为气态磷单质并去除,采用X射线衍射分析(XRD)残渣的组成和热重质谱(TGA-MS)分析反应过程.结果表明,添加氯化钙可显著提高污泥焚烧灰除磷效率,氯化钙的最优添加量为25％质量分数,此时污泥焚烧灰除磷效率为82％.XRD结果显示,污泥焚烧灰经熔盐处理后...     

驯化的活性污泥强化降解土壤中氯酚的研究

以接种驯化的活性污泥为生物强化手段,在小型生物泥浆反应器中,研究了受氯酚污染土壤的修复情况.考查了添加驯化活性污泥对土壤中氯酚降解的强化效果,并对土壤中邻氯苯酚(2-CP)、对氯苯酚(4-CP)和2,4-二氯酚(2,4-DCP)在单一污染体系中的降解情况进行了研究.结果表明,在生物泥浆反应器中添加用邻氯苯酚(2-CP)驯化的活性污泥可以明显地促进土壤泥浆中2-CP的降解,是一种有效的强化手段.该方法对土壤中的4-CP和2,4-DCP也有较好的降解效果,对三种氯酚的降解速率由大到小的顺序为2-CP,4-CP,2,4-DCP.反应结束时,泥浆体系中剩余的氯酚基本都残留在土壤中,固液分离后的水相可以直接排放或者在土壤修复过程中循环利用.