环境基础设施运营现状及市场化对策

本文对建立环境基础设施社会化投入机制和运营机制提出五条对策建议：即加强规划管理、建立社会化投入机制、推行环保设施运营市场化,发展股份制污染防治企业,加强法制建设并制定配套政策。     

Photosensitivity sources of dissolved organic matter from wastewater treatment plants and their mediation effect on 17α-ethinylestradiol photodegradation

● EE2 photodegradation behavior in the presence of four WWTPs’ DOM was explored. ● The ³DOM* played a major role in the EE2 photodegradation mediated by WWTPs’ DOM. ● The A²/O process DOM contained more aromatic and oxygen-containing substances. ● Possible photosensitivity sources of DOM in the A²/O process were proposed. Dissolved organic matter (DOM) from each treatment process of wastewater treatment plants (WWTPs) contains abundant photosensitive substances, which could significantly affect the photodegradation of 17α-ethinylestradiol (EE2). Nevertheless, information about EE2 photodegradation behavior mediated by DOM from diverse WWTPs and the photosensitivity sources of such DOM are inadequate. This study explored the photodegradation behavior of EE2 mediated by four typical WWTPs’ DOM solutions and investigated the photosensitivity sources of DOM in the anaerobic-anoxic-oxic (A²/O) process. The parallel factor analysis identified three varying fluorescing components of these DOM, tryptophan-like substances or protein-like substances, microbial humus-like substances, and humic-like components. The photodegradation rate constants of EE2 were positively associated with the humification degree of DOM (P < 0.05). The triplet state substances were responsible for the degradation of EE2. DOM extracted from the A²/O process, especially in the secondary treatment process had the fastest EE2 photodegradation rate compared to that of the other three processes. Four types of components (water-soluble organic matter (WSOM), extracellular polymeric substance, humic acid, and fulvic acid) were separated from the A²/O process DOM. WSOM had the highest promotion effect on EE2 photodegradation. Fulvic acid-like components and humic acid-like organic compounds in WSOM were speculated to be important photosensitivity substances that can generate triplet state substances. This research explored the physicochemical properties and photosensitive sources of DOM in WWTPs, and explained the fate of estrogens photodegradation in natural waters.     

MS/MS的原理和GC/MS/MS在环境分析中的应用

介绍了空间串联质谱和时间串联质谱的原理、结构和特点 ;描述了时间串联质谱的离子化、母离子选择和储存、碰撞诱导裂解、离子抛出和检测的分析过程以及离子阱串联质谱与气相色谱联用在二恶英、农药残留、多氯联苯 ,多环芳烃和环境激素等环境分析中的应用。     

京津冀区域PM2.5中碳组分污染特征研究

为了解京津冀区域PM_(2.5)中碳组分污染特征,于2015年7月和10月及2016年1月和4月在北京、天津、保定、石家庄、沧州5个城市同步采集PM_(2.5)样品,采用热/光分析法分析样品中有机碳(OC)和元素碳(EC),使用OC/EC最小比值法估算二次有机碳(SOC).结果表明:京津冀区域主要城市OC、EC和SOC的年均浓度分别为12.9~28.5、4.1~7.9和3.3~10.4μg·m~(-3),OC/EC和SOC/OC的比值分别为2.4~3.0和0.26~0.32.OC和EC的浓度呈现保定石家庄沧州天津北京的空间分布特点和夏季春季秋季冬季的季节变化特点.OC/EC的比值及OC和EC的相关性在夏季最低,冬季最高,这可能与京津冀区域冬季采暖燃煤有关,冬季不利的气象条件也加剧了碳质气溶胶污染.冬季较高的SOC浓度主要与低温、气态前体物的增加以及频繁出现的逆温、小风和混合层高度降低等不利气象条件有关.京津冀区域碳质气溶胶的污染特征具有空间相似性.     

Toxicity of Cu (II) to the green alga <Emphasis Type="Italic">Chlorella vulgaris</Emphasis>: a perspective of photosynthesis and oxidant stress

The toxic effects of Cu (II) on the freshwater green algae Chlorella vulgaris and its chloroplast were investigated by detecting the responses of photosynthesis and oxidant stress. The results showed that Cu (II) arrested the growth of C. vulgaris and presented in a concentration- and time-dependent trend and the SRichards 2 model fitted the inhibition curve best. The chlorophyll fluorescence parameters, including qP, Y (II), ETR, F _v /F _m , and F _v /F ₀, were stimulated at low concentration of Cu (II) but declined at high concentration, indicating the photosystem II (PSII) of C. vulgaris was destroyed by Cu (II). The chloroplasts were extracted, and the Hill reaction activity (HRA) of chloroplast was significantly decreased with the increasing Cu (II) concentration under both illuminating and dark condition, and faster decline speed was observed under dark condition. Activities of superoxide dismutase (SOD) and catalase (CAT) and malondialdehyde (MDA) content were also significantly decreased at high concentration Cu (II), companied with a large number of reactive oxygen species (ROS) production. All these results indicated a severe oxidative stress on algal cells occurred as well as the effect on photosynthesis, thus inhibiting the growth of algae, which providing sights to evaluate the phytotoxicity of Cu (II).     

不同浸提剂对污染河道底泥中重金属的浸出影响

以某有色金属冶炼企业排放口下游河道底泥为研究对象,分别采用无机酸(盐酸、硫酸、硝酸)和有机酸(醋酸、柠檬酸、苹果酸和丁二酸)研究在不同酸性条件(pH为2~6)下Pb、Cd、Zn、Cu的浸出效果。结果表明,有机酸的浸提能力明显高于无机酸,且4种重金属的浸出浓度均随着pH的升高而迅速降低。对无机酸而言,当pH3时,重金属的浸出浓度趋于稳定;对有机酸而言,在pH为2~5的较大范围内,醋酸表现出较高的浸提能力,而柠檬酸对Pb和Cu没有明显的浸出效果。结合泥质特点,从重金属的络合、沉淀、水解、吸附等反应过程对其浸出特征进行了分析,同时提出醋酸良好的缓冲能力是其浸提效果优于其他有机酸的重要原因。     

CNTs-CeO_2/H_2O_2复合光催化氧化体系降解水中酸性橙Ⅱ

运用"化学沉淀法",将Ce O2负载到碳纳米管(CNTs)上制备复合光催化剂,采用"单因素实验法"优化了制备条件。运用透射电镜和X射线衍射仪对复合光催化剂进行了表征。结果表明,负载到CNTs上的Ce O2为多晶面心立方结构,尺寸大小在6~10 nm之间,其在CNTs上分散效果好,负载均匀且负载率高。在溶液p H为5,CNTs-Ce O2用量为0.50g/L并光照2 h后,酸性橙Ⅱ的光脱色率和TOC去除率分别达到64.71%和44.25%;加入0.02 mmol/L H2O2后,CNTsCe O2/H2O2复合体系对酸性橙Ⅱ的光脱色率和TOC去除率分别提高至91.35%和82.40%。这预示着CNTs-Ce O2/H2O2复合光催化氧化体系在对水中偶氮染料的光催化处理方面具有潜在的应用价值。     

高炉渣制备聚硅酸硫酸铝铁混凝剂

以高炉渣为原料,分别采用酸浸及碱浸-酸化工艺得到铁、铝离子及聚硅酸,再将铁、铝离子引入聚硅酸制得聚硅酸硫酸铝铁(PSAFS)混凝剂。考察了PSAFS的聚合条件对焦化废水混凝效果的影响,并与市售混凝剂进行了对比。实验结果表明:PSAFS的最佳制备条件为n(Al+Fe)∶n(Si)=0.53,混凝剂p H=1,熟化时间0.5 h,熟化温度60℃;PSAFS加入量为4 m L/L时,混凝效果最好,对焦化废水的浊度和COD的去除率分别达到98.9%和74.5%;PSAFS的性能优于市售的3种混凝剂。     

UV_(185 nm)-H_2O_2组合工艺处理高浓度棘白菌素类抗生素发酵废水

采用UV_(185 nm)-H_2O_2组合工艺处理高浓度棘白菌素类抗生素发酵废水。结果表明:UV_(185 nm)-H_2O_2组合工艺较好地实现了高浓度棘白菌素类抗生素发酵废水的强化处理,其处理效果明显优于单独UV_(185 nm)光氧化工艺;在废水pH为2.50、光照时间为60 min、H_2O_2投加量为5 g/L、反应温度为室温的条件下,UV_(185 nm)-H_2O_2组合工艺对废水色度和COD的去除率分别高达96.4%和46.9%;该联合氧化过程需在酸性体系中进行;联合氧化过程中产生了大量蜂王浆提取物类黑褐色物质,处理出水中显色物质的种类明显减少,实现了废水的高效脱色。