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1.
目前广泛分布在环境中的药物及个人护理品(pharmaceuticals and personal care products, PPCPs)在环境中的迁移、转化和处理已成为环境科学与工程研究的一个新的领域。污水处理厂排水是PPCPs进入环境中的主要途径。介绍了污水处理过程中传统活性污泥法、膜处理技术以及氧化处理等主要工艺对PPCPs的去除机理,并对去除效果进行了比较。以传统活性污泥法及在其改进后的膜处理技术为基础的大部分现有污水处理厂只能够去除一部分PPCPs,并且主要通过吸附(如对于吐纳麝香、佳乐麝香、萨利麝香等脂溶性较高的有机物)和生物降解作用(如对于布洛芬,17β-雌二醇,雌酮等易反应的有机物)。然而,吸附了PPCPs的污泥通过土壤施肥又将PPCPs带入土壤中,进而会渗滤到地下水,或随径流水进入地表水中。因此,PPCPs并没有从根本上得以去除。相比之下氧化处理工艺(如氯化、臭氧氧化、紫外辐射)或这些工艺的组合能够将大部分的PPCPs进行氧化,去除效果明显优于以上2种技术。然而,氧化后产物的种类和毒理性需要更深入的研究。  相似文献   

2.
蔡武 《污染防治技术》1996,9(3):150-151
依据《工业固体废物有害特性试验与监测分析方法(试行)》一书,选用南京市几种有代表性的工业废渣,对其腐蚀性及浸出毒性进行了分析测定,填补了南京市目前对固体废物试验研究的不足,为固体废物的污染监测,废物处置的安全性评价提供一定依据。  相似文献   

3.
西安市大气中多环芳烃的季节变化及健康风险评价   总被引:1,自引:0,他引:1  
对西安市2009年6月-2010年5月空气中的总悬浮颗粒(TSP)和气态样品进行了连续采样,利用GC—MS对16种PAHs进行分析。∑PAHs浓度(气相+颗粒相)范围为39.93~1032.46ng/m^3,平均值为197.34ng/m^3;其中,冬季大气中∑PAHs浓度最大,相对浓度的范围为31.21%~72.98%,而夏季的浓度最小;检测出16种2~6环的PAHs,其中以3—4环为主。利用特征分子比值法和因子分析进行源解析,发现研究区PAHs的主要来源为燃煤和机动车尾气排放。通过苯并(a)芘(BaP)等效毒性(BEQ)和苯并(a)芘等效致癌浓度(BaPE)进行健康风险评价,结果显示,西安大气中PAHs的毒性具有明显的季节差异,特别是秋季和冬季大气中PAHs对人类的健康存在较大的潜在威胁。  相似文献   

4.
新型环境测试舱研制、性能评价及释放模拟   总被引:1,自引:0,他引:1  
研制了一种新型环境测试舱,此舱系统可用于研究室内材料中挥发性有机物(VOCs)释放特征和释放机理。详细介绍舱的设计,讨论舱系统的优缺点,并对舱的性能进行评价测试。结果表明,温度和相对湿度的准确性分别为≤0.5℃和≤ 3.1%,空气混合水平达到92.9%,回收率达到85.2%。根据回收率实验结果,用经验模型和VB模型模拟对二氯苯(p-DCB)释放,模拟结果与实测值吻合很好。  相似文献   

5.
以活性铝氧化物AlOxHy处理某高氟地下水的中试实验获得的吸附剂废料AlOxHy-Fn为对象,考察其对三价砷(As(Ⅲ))和五价砷(As(Ⅴ))吸附去除性能,并对吸附机理进行了探讨。研究显示,AlOxHy-Fn为多孔无定型且具有不规则表面的絮状结构,比表面积为218.88m2/g,零电荷点pHZPC在pH为8左右;AlOxHy-Fn可快速吸附As(Ⅲ)和As(Ⅴ),且反应24h后的平衡吸附量分别为0.60和3.41mg/g,朗格缪尔模型可以很好地描述As(Ⅲ)和As(Ⅴ)在AlOxHy-Fn表面的吸附,且As(Ⅲ)和As(Ⅴ)的最大吸附容量分别为13.63和63.27mg/g;AlOxHy-Fn在pH=4~10范围内对As(Ⅴ)去除率在90%以上,As(Ⅲ)在中性和弱碱性pH范围内吸附效果较好,但去除率仍在32%以下。AlOxHy-Fn表面性质、砷形态分布特征等对As(Ⅲ)与As(Ⅴ)的吸附有重要影响,电负性As(Ⅴ)较电中性As(Ⅲ)更容易吸附在AlOxHy-Fn表面。AlOxHy-Fn吸附除砷过程中,在pH为6时氟溶出量最低(0.40mg/g),过高或过低pH均会导致氟溶出量增大;氟溶出量与As(Ⅴ)吸附量之间有明显正相关关系(R2=0.97),但与As(Ⅲ)吸附量无相关关系;铝溶出量在pH为4~10范围内均很低。将AlOxHy-Fn回用作为除砷吸附剂去除工业含砷废水的砷具有良好的技术经济可行性,且将As(Ⅲ)氧化为As(Ⅴ)是提高去除效果的重要手段。  相似文献   

6.
用水生生物对重金属污染土壤进行生态毒理评价   总被引:1,自引:0,他引:1  
应用斜生栅藻(Scenedesmus obliquus)和明亮发光杆菌T3(Photobacterium phosphoreum)急性毒性实验方法对重金属污染土壤的进行生态毒理评价,结果表明,斜生栅藻的生长繁殖率和发光菌的相对发光度与土壤中的重金属含量明显相关,并且随重金属投加量的增加,其生长繁殖率和发光度逐渐降低。对3种测试参数进行比较可知,斜生栅藻细胞数增长率是最敏感的土壤毒性检测指标。土壤的毒性在复合污染的条件下比在单一污染的条件下高很多。本研究的结果可以为污染土壤的优先修复提供理论依据。  相似文献   

7.
壳聚糖复合絮凝剂处理造纸废水的实验研究   总被引:3,自引:0,他引:3  
研究并考察了壳聚糖复合絮凝剂对造纸污水中COD和SS的絮凝效果,结果表明,当复合絮凝剂的配方和处理条件为:聚合硫酸铁(PFS)60 mg/L聚丙烯酰胺(PAM)2 mg/L壳聚糖(CTS)0.4 mg/L,pH为7.5时,其絮凝效果最佳,此时它对水中COD与SS的去除率分别达到57.4%和97.6%, 与传统絮凝剂PAC/PAM相比,COD与SS的去除率分别提高了10.1%和5.2%,药剂成本下降了21.1%,具有明显的经济效益与环境效益。  相似文献   

8.
先用水热法制备了纳米级NiFe2O4磁核,然后采用均匀沉淀法在NiFe2O4磁核表面包覆TiO2,制备了一种新型磁性纳米光催化剂TiO2/NiFe2O4。通过实验确定了制备TiO2/NiFe2O4的最佳Ti/Ni(摩尔比)为30/1,用X射线衍射(XRD)、透射电子显微镜(TEM)、紫外-可见(UV—Vis)漫反射、热重一差示扫描量热分析(TG-DSC)、磁力学测试等手段对其进行了表征。以甲基橙的水溶液为模拟污染物,评价了TiO2/NiFe2O4的光催化性能,在光照2h后,甲基橙的脱色率可达98.5%。研究结果表明,TiO2/NiFe2O4是一种可重复使用的高效光催化剂。  相似文献   

9.
控制DO及FA条件下短程硝化过程系统稳定性研究   总被引:5,自引:0,他引:5  
采用SBR工艺以水产品加工废水为研究对象,同时控制进水游离氨(FA)为0.96~1.25mg!L,溶解氧(DO)为1~2mg/L,实现了稳定的短程硝化过程。在此条件下,亚硝化率及氨氮去除率分别大于95%和88%,有机物(COD)去除率在90%以上,亚硝化速率维持在0.9666×10^-3-1.0375×10^-3mgNO2-N/(mgMLSS·h)之间。研究结果表明,同时控制DO及FA在适当范围之内可以获得稳定的短程硝化过程,并可降低系统能耗。本实验采用较低的FA浓度与较高的DO浓度(与OLAND工艺比较)得到了稳定的短程硝化过程,对水产品加工废水处理具有重要应用价值。  相似文献   

10.
以聚合氯化铝PAC为混凝剂,纳米SiO2为助凝剂,对含有下列微污染物:十二烷基硫酸钠(SDS)、氨氮(NH3-N)或腐植酸(HA)的高岭土悬浊液进行混凝沉降实验。借助形态学理论、电镜观察与图像分析技术,研究纳米SiO2对微污染物的助凝作用效果、吸附特性与絮体结构的形态学特征。结果表明:(1)在含有HA、SDS、NH3-N的模拟原水中,污染物去除率与浊度去除率的相关性随污染物分子量的增大而增强;(2)纳米SiO  相似文献   

11.
Phthalates are plasticizers and are concerned environmental endocrine-disrupting compounds. Due to their extensive usage in plastic manufacturing and personal care products as well as the potential to leach out from these products, phthalates have been detected in various aquatic environments including drinking water, groundwater, surface water, and wastewater. The primary source of their environmental occurrence is the discharge of phthalate-laden wastewater and sludge. This review focuses on recent knowledge on the occurrence of phthalate in different aquatic environments and their fate in conventional and advanced wastewater treatment processes. This review also summarizes recent advances in biological removal and degradation mechanisms of phthalates, identifies knowledge gaps, and suggests future research directions.  相似文献   

12.

Purpose

The large global production of plastics and their presence everywhere in the society and the environment create a need for assessing chemical hazards and risks associated with plastic products. The aims of this study were to determine and compare the toxicity of leachates from plastic products made of five plastics types and to identify the class of compounds that is causing the toxicity.

Methods

Selected plastic types were those with the largest global annual production, that is, polypropylene, polyethylene, and polyvinyl chloride (PVC), or those composed of hazardous monomers (e.g., PVC, acrylonitrile?Cbutadiene?Cstyrene [ABS], and epoxy). Altogether 26 plastic products were leached in deionized water (3?days at 50°C), and the water phases were tested for acute toxicity to Daphnia magna. Initial Toxicity Identification Evaluations (C18 filtration and EDTA addition) were performed on six leachates.

Results

For eleven leachates (42%) 48-h EC50s (i.e the concentration that causes effect in 50 percent of the test organisms) were below the highest test concentration, 250 g plastic/L. All leachates from plasticized PVC (5/5) and epoxy (5/5) products were toxic (48-h EC50s ranging from 2 to 235?g plastic/L). None of the leachates from polypropylene (5/5), ABS (5/5), and rigid PVC (1/1) products showed toxicity, but one of the five tested HDPE leachates was toxic (48-h EC50 17?C24?g plastic/L). Toxicity Identification Evaluations indicated that mainly hydrophobic organics were causing the toxicity and that metals were the main cause for one leachate (metal release was also confirmed by chemical analysis).

Conclusions

Toxic chemicals leached even during the short-term leaching in water, mainly from plasticized PVC and epoxy products.  相似文献   

13.
Usage of plastics has been ever increasing and now poses a tremendous threat to the environment. Millions of tons of plastics are produced annually worldwide, and the waste products have become a common feature at overflowing bins and landfills. The process of converting waste plastic into value-added fuels finds a feasible solution for recycling of plastics. Thus, two universal problems such as problems of waste plastic management and problems of fuel shortage are being tackled simultaneously. Converting waste plastics into fuel holds great promise for both the environmental and economic scenarios. In order to carry out the study on plastic wastes, the pyrolysis process was used. Pyrolysis runs without oxygen and in high temperature of about 250–300 °C. The fuel obtained from plastics is blended with B20 algae oil, which is a biodiesel obtained from microalgae. For conducting the various experiments, a 10-HP single-cylinder four-stroke direct-injection water-cooled diesel engine is employed. The engine is made to run at 1500 rpm and the load is varied gradually from 0 to 100 %. The performance, emission and combustion characteristics are observed. The BTE was observed to be higher with respect to diesel for plastic-biodiesel blend and biodiesel blend by 15.7 and 12.9 %, respectively, at full load. For plastic-biodiesel blend, the emission of UBHC and CO decreases with a slight increase in NO x as compared to diesel. It reveals that fuel properties are comparable with petroleum products. Also, the process of converting plastic waste to fuel has now turned the problems into an opportunity to make wealth from waste.  相似文献   

14.
采用生物活性剂对无机粉体进行表面处理,利用碱性无机材料的吸水性能制备出含少量淀粉和碱性无机材料的光钙型可环境消纳聚乙烯制品,通过力学性能、ASTM生物降解性能和卫生性能等分析,结果表明,该制品达到了HJBZ12-2000标准中规定的包装制品的标准要求和生物降解率的技术要求.  相似文献   

15.
Butyltin compounds (BTs) including mono-(MBT), di-(DBT) and tributyltin (TBT) were determined in livers of humans and wild terrestrial mammals, such as raccoon dogs (Nyctereutes procyonoids) and monkeys (Macaca fuscata) from Japan. In addition, 22 samples of plastic products were analyzed. BT residues were detected in all the liver samples of humans and raccoon dogs, with concentrations of <360 ng/g wet wt, whereas concentrations in the liver of monkeys were either less than the detection limit or were only in trace levels. Elevated concentrations of BTs, particularly DBT (<140,000 ng/g) and MBT (<130,000 ng/g), were found in some plastic products, such as baking parchments made from siliconized paper and gloves made up from polyurethane. The results of a cooking test using the above baking parchment indicated the transfer of BTs to foodstuffs. These observations suggest expansion of BT contamination among terrestrial mammals. BT pollution from industrial appliances, such as plastic stabilizers and catalysts other than those of marine origin as antifouling agents, are suggested as alternative sources of exposure.  相似文献   

16.
Quantities of bisphenol a leached from plastic waste samples   总被引:9,自引:0,他引:9  
Yamamoto T  Yasuhara A 《Chemosphere》1999,38(11):2569-2576
To quantify the leaching of bisphenol A into water, various samples of plastic waste were cut into small pieces, soaked in water for two weeks at room temperature in the dark, and the concentration of bisphenol A in the water determined by gas chromatography/mass spectrometry (GC/MS). The amount of bisphenol A leached from the plastic wastes ranged from undetectable to 139 micrograms/g. The detection limit was 2 ng/g when 100 g of plastic waste was used. Polyvinyl chloride products yielded the highest concentrations because bisphenol A is used in its manufacture as a stabilizer.  相似文献   

17.

In recent times, the issue of plastic recycling has become one of the leading issues of environmental protection and waste management. Polymer materials have been found an application in many areas of daily life and industry. Along with their extended use, the problem of plastic wastes appeared because, after withdrawal from use, they became persistent and noxious wastes. The possibility of reusing polymeric materials gives a possibility of valorization—a second life—and enables effective waste utilization to obtain consumable products. The 3D printing market is a well-growing sector. Printable filaments can be made from a variety of thermoplastic materials, including those from recycling. This paper focuses on a review of the available literature on the production of filaments for 3D printers from recycled polymers as the alternative to present approach of central selective collection of plastics. The possibility of recycling of basic thermoplastic materials and the impact of processing on their physicochemical and mechanical properties were verified (Lanzotti et al. 2019). In addition, commercially available filaments produced from recycled materials and devices which allow self-production of filaments to 3D printing from plastic waste were reviewed.

  相似文献   

18.
Rupp S  Metzger JW 《Chemosphere》2005,60(11):1644-1651
Polybrominated diphenyl ethers (PBDEs) are a group of brominated flame retardants (BFRs) used mainly as additives in different kinds of plastic material. Various PBDEs are found in all environmental compartments as well as in tissue and blood serum of animals and humans due to their persistence and tendency to bioaccumulate. Emission of PBDEs into the environment can occur during recycling of PBDE-containing plastic material or during their uncontrolled or insufficient combustion as e.g. in accidental fires or landfill fires. Under these circumstances, PBDEs can also function as precursor molecules for the formation of polybrominated dibenzodioxins (PBDDs) and dibenzofurans (PBDFs). In this study, we qualitatively investigated the reaction of two PBDE congeners, 2,2′,4,4′-tetrabromo diphenyl ether (BDE 47) and 2,2′,4,4′,5,5′-hexabromo diphenyl ether (BDE 153), as well as hexabromobenzene (HBB), a flame retardant used in the past, when exposed to temperatures between 250 °C and 500 °C. The formed reaction products were analysed by high resolution gas chromatography–low resolution mass spectrometry (HRGC-LRMS). Among others brominated–chlorinated diphenyl ethers were formed by chlorodebromination of the PBDEs. In addition, thermolysis of BDE 47 and BDE 153 in the presence of tetrachloromethane as model substance for an organic chlorine source was studied. Thermal treatment of HBB resulted in the formation of brominated–chlorinated benzenes.  相似文献   

19.
餐厨垃圾中典型组分的裂解液化特征研究   总被引:1,自引:1,他引:0  
利用实验室规模的实验装置管式加热炉进行餐厨垃圾热解实验,实验分析了反应温度对餐厨垃圾热解产物分布的影响,米饭、白菜、猪肉、塑料和纸5种原料在最佳温度下可实现热解油质量产率的最大化,分别为45.02%、24.55%、61.19%、73.77%和24.86%。其中,米饭和白菜热解油含水率较高,可达到30%~40%,将含水率降到15%后,测定热值分别为25.51 MJ/kg和17.75 MJ/kg。塑料和纸混合热解时,塑料热解过程的放热效应可缩小纸的热解温度区间,增加热解油产量。红外光谱分析厨余热解油包含多种含氧有机物。通过气质联用仪(GC-MS)分析塑料热解油和塑料与纸混合热解油在180℃以下蒸馏出的液相产物,主要组分为烷烃和烯烃,从成分和热值分析,与汽油、柴油相近。  相似文献   

20.
GOAL, SCOPE AND BACKGROUND: Global multi-media box models are used to calculate the fate of persistent organic chemicals in a global environment and assess long-range transport or arctic contamination. Currently, such models assume substances to degrade in one single step. In reality, however, intermediate degradation products are formed. If those degradation products have a high persistence, bioaccumulation potential and / or toxicity, they should be included in environmental fate models. The goal of this project was to gain an overview of the general importance of degradation products for environmental fate models, and to expand existing, exposure-based hazard indicators to take degradation products into account. METHODS: The environmental fate model CliMoChem was modified to simultaneously calculate a parent compound and several degradation products. The three established hazard indicators of persistence, spatial range and arctic contamination potential were extended to include degradation products. Five well-known pesticides were selected as example chemicals. For those substances, degradation pathways were calculated with CATABOL, and partition coefficients and half-lives were compiled from literature. RESULTS: Including degradation products yields a joint persistence value that is significantly higher than the persistence of the parent compound alone: in the case of heptachlor an increase of the persistence by a factor of 58 can be observed. For other substances, the increase is much smaller (4% for alpha-HCH). The spatial range and the arctic contamination potential (ACP) can increase significantly, too: for 2,4-D and heptachlor, an increase by a factor of 2.4 and 3.5 is seen for the spatial range. However, an important increase of the persistence does not always lead to a corresponding increase in the spatial range: the spatial range of aldrin increases by less than 50%, although the persistence increases by a factor of 20 if the degradation products are included in the assessment. Finally, the arctic contamination potential can increase by a factor of more than 100 in some cases. DISCUSSION: Influences of parent compounds and degradation products on persistence, spatial range and ACP are discussed. Joint persistence and joint ACP reflect similar characteristics of the total environmental exposure of a substance family (i.e., parent compound and all its degradation products). CONCLUSIONS: The present work emphasizes the importance of degradation products for exposure-based hazard indicators. It shows that the hazard of some substances is underestimated if the degradation products of these substances are not included in the assessment. The selected hazard indicators are useful to assess the importance of degradation products. RECOMMENDATIONS AND PERSPECTIVES: It is suggested that degradation products be included in hazard assessments to gain a more accurate insight into the environmental hazard of chemicals. The findings of this project could also be combined with information on the toxicity of degradation products. This would provide further insight into the importance of degradation products for environmental risk assessments.  相似文献   

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