石油炼制行业新旧污染物排放标准的差异

分别介绍了旧标准GB 8978—1996《污水综合排放标准》、GB 16297—1996《大气污染物综合排放标准》和新标准GB 31570—2015《石油炼制工业污染物排放标准》的核心内容。从适用范围、排放限值和污染控制因子3个方面分析了石油炼制行业新旧污染物排放标准的差异。     

三种环境动力学模型建模方式的比较

在农药和化学品的风险评估工作中,环境动力学模型正得到越来越多的应用。采用Stella软件、Matlab M文件和Matlab Simulink 组件3种建模方式分别构建了微宇宙、湖泊和海湾系统的多介质环境动力学模型,并对3种方式的建模难度、计算耗时及模型直观性进行了比较。研究结果表明：Stella模型最直观,但提供的计算方法有限,更适用于微分方程数量不多且计算周期短的模型;M文件模型建模速度最快,但在直观性和计算速度上没有优势,不建议在环境动力学模型中使用;Simulink模型兼具直观性和计算速度快的优点,无论微分方程数量多少,在需要进行长周期计算的模型中都最具优势。     

旋转填充床中Fenton+O_3氧化降解模拟阿莫西林废水

以旋转填充床(RPB)作为反应装置,研究了Fenton工艺与Fenton+O3工艺处理模拟阿莫西林废水的效果,考察了FeSO4·7H2O的投加量、温度、旋转床转速、液体流量及pH对COD去除率的影响。实验表明,Fenton+O3工艺的COD脱除率及BOD5/COD相对于Fenton工艺分别提升26.7%和140%。该工艺在pH为3、温度为25℃、液体流量30 L/h、气体流量2.5 L/h、转速800 r/min、H2O2的投加量为1 mmol/L及Fe2+投加量为0.4 mmol/L的条件下,100 mg/L的模拟阿莫西林废水中COD的去除率达到57.9%,BOD5/COD从0增加到0.36,满足后续生化处理要求。     

New insights for the risk of bisphenol A: Inhibition of UDP-glucuronosyltransferases (UGTs)

Bisphenol A (BPA), the important endocrine-disrupting chemical (EDC), has been reported to be able to induce various toxicity. The present study aims to understand the toxicity behavior of bisphenol A through evaluating the inhibition profile of bisphenol A towards UDP-glucuronosyltransferase (UGT) isoforms. In vitro recombinant UGTs-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction was employed as probe reaction for all the tested UGT isoforms. The results showed that bisphenol A exerted stronger inhibition towards UGT2B isoforms than UGT1A isoforms. Furthermore, the inhibition kinetic type and parameters (K_i) were determined for the inhibition of bisphenol A towards UGT2B4, 2B7, 2B15, and 2B17. Bisphenol A exhibited the competitive inhibition towards UGT2B4, and noncompetitive inhibition towards UGT2B7, 2B15 and 2B17. The inhibition kinetic parameters (K_i) were calculated to be 1.1, 32.6, 5.6, and 19.9 μM for UGT2B4, 2B7, 2B15 and 2B17, respectively. In combination with the in vivo concentration of bisphenol A, the elevation of exposure dose was predicted to increase by 29.1%, 1%, 5.7%, and 1.6% for UGT2B4, 2B7, 2B15, and 2B17, indicating the high influence of bisphenol A towards the in vivo UGT2B isofroms-mediated metabolism of xenobiotics and endogenous substances. All these data provide the supporting information for deeper understanding of toxicology of bisphenol A.     

Electrocatalytic biofilm reactor for effective and energy-efficient azo dye degradation: the synergistic effect of MnOx/Ti flow-through anode and biofilm on the cathode

● MnO _x /Ti flow-through anode was coupled with the biofilm-attached cathode in ECBR. ● ECBR was able to enhance the azo dye removal and reduce the energy consumption. ● Mn^IV=O generated on the electrified MnO _x /Ti anode catalyzed the azo dye oxidation. ● Aerobic heterotrophic bacteria on the cathode degraded azo dye intermediate products. ● Biodegradation of intermediate products was stimulated under the electric field. Dyeing wastewater treatment remains a challenge. Although effective, the in-series process using electrochemical oxidation as the pre- or post-treatment of biodegradation is long. This study proposes a compact dual-chamber electrocatalytic biofilm reactor (ECBR) to complete azo dye decolorization and mineralization in a single unit via anodic oxidation on a MnO_x/Ti flow-through anode followed by cathodic biodegradation on carbon felts. Compared with the electrocatalytic reactor with a stainless-steel cathode (ECR-SS) and the biofilm reactor (BR), the ECBR increased the chemical oxygen demand (COD) removal efficiency by 24 % and 31 % (600 mg/L Acid Orange 7 as the feed, current of 6 mA), respectively. The COD removal efficiency of the ECBR was even higher than the sum of those of ECR-SS and BR. The ECBR also reduced the energy consumption (3.07 kWh/kg COD) by approximately half compared with ECR-SS. The advantages of the ECBR in azo dye removal were attributed to the synergistic effect of the MnO_x/Ti flow-through anode and cathodic biofilms. Catalyzed by Mn^IV=O generated on the MnO_x/Ti anode under a low applied current, azo dyes were oxidized and decolored. The intermediate products with improved biodegradability were further mineralized by the cathodic aerobic heterotrophic bacteria (non-electrochemically active) under the stimulation of the applied current. Taking advantage of the mutual interactions among the electricity, anode, and bacteria, this study provides a novel and compact process for the effective and energy-efficient treatment of azo dye wastewater.     

Heavy metal contamination of urban soils and dusts in Guangzhou, South China

The heavy metal concentrations of soil and dust samples from roadside, residential areas, parks, campus sport grounds, and commercial sites were studied in Guangzhou, South China. Heavy metals in samples were determined by inductively coupled plasma atomic emission spectrophotometer following acidic digestion with HClO₄ + HF + HNO₃. High concentrations, especially of Cd, Pb, and Zn, were found with mean concentrations of Cd, Cr, Cu, Ni, Pb, and Zn in the urban dusts being 4.22?±?1.21, 62.2?±?27.1, 116?±?30, 31.9?±?12.6, 72.6?±?17.9, and 504?±?191 mg/kg dry weight, respectively. The respective levels in urban soils (0.23?±?0.19, 22.4?±?13.8, 41.6?±?29.4, 11.1?±?5.3, 65.4?±?40.2, and 277?±?214 mg/kg dry weight, respectively), were significantly lower. The integrated pollution index of six metals varied from 0.25 to 3.4 and from 2.5 to 8.4 in urban soils and dusts, respectively, with 61 % of urban soil samples being classified as moderately to highly polluted and all dust samples being classified as highly polluted. The statistical analysis results for the urban dust showed good agreement between principal component analysis and cluster analysis, but distinctly different elemental associations and clustering patterns were observed among heavy metals in the urban soils. The results of multivariate statistic analysis indicated that Cr and Ni concentrations were mainly of natural origin, while Cd, Cu, Pb, and Zn were derived from anthropogenic activities.     

近十年水磨河水质变化特征研究

利用水磨河2001—2010年各断面实测资料,采用单因子法和综合污染指数法分析了近十年该流域各断面主要污染物超标情况,沿程变化特征及年际、季节变化趋势。结果表明,搪瓷厂泉断面、七纺桥断面水质有所好转,下游联丰桥断面、米泉桥断面污染程度逐渐加重,超标污染项目逐年增加。高锰酸盐指数、氨氮、总磷浓度值在联丰桥断面直线上升,石...     

汶川8.0级地震都江堰市天然气系统震害分析及救灾过程

四川都江堰市地处龙门山主山前边界大断裂上,在汶川8.0级地震烈度分布图中属于Ⅸ度区,是地震受灾最严重的城市之一。作为城市生命线的天然气供应链在本次地震中遭遇了一定的破坏。通过对都江堰市天然气系统的基本构成、震害情况以及应急救灾过程等的调查与整理,对都江堰燃气系统中门站、CNG加气站、中压配气管网及低压配气支管各组成部分在地震中的震害情况进行了分析,对震后的应急处置措施、供气恢复策略及灾后重建工作进行了综述,总结了汶川地震中都江堰天然气系统的应灾经验及救灾环节中的不足之处,并就如何提高燃气系统的抗震应灾能力提出建议。     

Emergy Assessment of a Wheat-Maize Rotation System with Different Water Assignments in the North China Plain

Sustainable water use is seriously compromised in the North China Plain (NCP) due to the huge water requirements of agriculture, the largest use of water resources. An integrated approach which combines the ecosystem model with emergy analysis is presented to determine the optimum quantity of irrigation for sustainable development in irrigated cropping systems. Since the traditional emergy method pays little attention to the dynamic interaction among components of the ecological system and dynamic emergy accounting is in its infancy, it is hard to evaluate the cropping system in hypothetical situations or in response to specific changes. In order to solve this problem, an ecosystem model (Vegetation Interface Processes (VIP) model) is introduced for emergy analysis to describe the production processes. Some raw data, collected by investigating or observing in conventional emergy analysis, may be calculated by the VIP model in the new approach. To demonstrate the advantage of this new approach, we use it to assess the wheat-maize rotation cropping system at different irrigation levels and derive the optimum quantity of irrigation according to the index of ecosystem sustainable development in NCP. The results show, the optimum quantity of irrigation in this region should be 240–330 mm per year in the wheat system and no irrigation in the maize system, because with this quantity of irrigation the rotation crop system reveals: best efficiency in energy transformation (transformity = 6.05E + 4 sej/J); highest sustainability (renewability = 25%); lowest environmental impact (environmental loading ratio = 3.5) and the greatest sustainability index (Emergy Sustainability Index = 0.47) compared with the system in other irrigation amounts. This study demonstrates that application of the new approach is broader than the conventional emergy analysis and the new approach is helpful in optimizing resources allocation, resource-savings and maintaining agricultural sustainability.     

Chemical and morphological characterization of aerosol particles at Mt. Krvavec, Slovenia, during the Eyjafjallajökull Icelandic volcanic eruption

Objective

In this work, continuous and size-segregated aerosol measurements at Mt. Krvavec, Slovenia, during the Eyjafjallajökull volcanic eruption were performed. Based on chemical and morphological characteristics of size-segregated particles, the presence of the volcanic aerosols after long-range transport to Slovenia was to be confirmed.

Results and conclusions

Continuous measurements with the aethalometer and SMPS indicated the suspected volcanic ash plume passing over the sampling site. The aerosols collected by discrete sampling showed a chemical signature similar to the known elemental signature of the Icelandic volcanic ash. Coarse particles showed a composition typical for silicates rich in metals; in many cases also S was present. Morphological analysis showed particles with features indicative of an explosive volcanic eruption, e.g., pumice and pumice shards, glass shards, minerals, evidence of steam condensation, etc. The high sulfate concentration associated with the fine particles resulted in sulfate crystallization within the cascade impactor leading to the formation of large structures resembling a “fern”. Mass size distributions for Fe, Ti, Mn, Ca, Na, and Mg showed one primary peak (for Fe, Mn, and Ti at 2.8 μm; for Ca, Na, and Mg at ca. 4 μm), which supports the fact that most of the particles in the coarse sizes were silicates rich in metals. The size distribution of the water-soluble SO ₄ ^2? showed a maximum peak at 0.75 μm, which also confirms the high sulfate concentration in the fine particles. Chemical and morphological characterization of aerosols collected at Mt. Krvavec indeed confirmed that volcanic ash plume passed over Slovenia.