Considerations about the enantioselective transformation of polycyclic musks in wastewater, treated wastewater and sewage sludge and analysis of their fate in a sequencing batch reactor plant

The present work consists of two distinct parts: in the first part enantioselective GC was used to separate the different enantiomeric/diastereomeric polycyclic musks, PCMs (HHCB, AHTN, AHDI, ATII and DPMI) including the main transformation product of HHCB, HHCB-lactone, in wastewater and sewage sludge. After optimization all PCMs were resolved on a cyclodextrin containing Rt-BDEXcst capillary GC column. Enantiomeric ratios of PCMs in a technical mixture were determined and compared to those obtained from enantioselective separation of wastewater and sewage sludge samples. In general, enantiomeric ratios were similar for most materials in influent, effluent and stabilized sewage sludge. However, the ratios for HHCB, AHDI and particularly ATII suggest some stereospecific removal of these compounds. In the second part, a field study was conducted on a wastewater treatment plant comprising a sequencing batch reactor. Concentrations of HHCB, AHTN, ADBI, AHDI, ATII, DPMI and HHCB-lactone were determined by non-enantioselective GC in daily samples of influent, effluent and activated sludge during one week. Mean concentrations in influent were 6900 and 1520 ng/l for HHCB and AHTN, respectively. The other PCMs exhibited contents 200 ng/l. Mean percent removal was between 61% (AHDI) and 87% (HHCB) resulting in mean effluent concentrations below 860 ng/l. HHCB-lactone concentration increased during wastewater treatment with a mean in the influent of 430 ng/l and in the effluent of 900 ng/l, respectively, indicating a degradation of HHCB.     

冬季原位生态组合技术改善二级出水净化效果分析

为改善冬季低温条件河流原位生态组合技术对微污染水净化效果,将某硬质纳污河道改造为实验河道。通过进水流量控制、铁炭填料内电解和耐寒植物3种优化措施,考察人工浮岛、生态河床和生态滤坝组合技术对污水处理厂二级出水净化情况。结果表明,在改善措施完成后,组合技术对COD的去除效果由14.3%提高至19%,NH_4~+-N和TN的去除效果由7.8%和13%提高至15.5%和22.8%,TP去除效果由6.3%提高至12.9%。铁炭内电解增加了脱氮微生物种属和丰度,使微生物活性由0.22 mg·g~(-1)增加至0.3 mg·g~(-1),硝化/反硝化强度由0.97 mg·(kg·h)~(-1)/2.69 mg·(kg·h)~(-1)增加至1.26 mg·(kg·h)~(-1)/3.11 mg·(kg·h)~(-1),显著改善组合技术的脱氮效果。此外,沿水流方向布置耐寒挺水植物-浮水植物-沉水植物,进水TP中55%～86.9%的颗粒态磷得到去除。这对提升寒冷地区受污染河流治理效果具有参考价值。     

黄浦江水质的模糊数学综合评价研究

在黄浦江的水质综合评价中,采用基于加权平均模型的模糊数学综合评价法进行评价,取得了良好的效果。研究结果表明,黄浦江水质基本属于Ⅲ～Ⅳ类水,偏Ⅳ类。并尝试采用SPSS统计软件进行多元统计分析,深入探讨各污染指标之间的相互关系,更好地了解黄浦江水质的污染特性。通过SPSS统计软件的相关分析结果表明,所选择的7项污染指标是有代表性的。     

斗轮机液压系统技术改造

从液压油污染、液压油油温升高、液压元件选择不合理、液压系统设计存在缺陷等几方面分析了斗轮堆取料机(以下简称斗轮机)液压系统长期存在的问题。根据液压系统的特点,确定了液压系统的改造设计;根据液压系统各种基本控制回路,确定了采用Spider 2全功能控制器对液压系统的控制方案和斗轮机液压系统的元件选型,并增加了液压油的温度控制功能。解决了斗轮机液压系统长期存在的缺陷和安全运行隐患,极大提高了生产效率和经济效益。     

燃油税费改革给客运经营造成的影响

2009年1月1日,全国正式实施成品燃油税。客运作为交通运输业的重要组成部分,燃油税费改革后会给客运市场现状带来大的改变,对客运经营产生直接影响,那么如何在改革中处理好客运经营带来的负面影响呢？燃油税臻改警给客运经黄造成的影响（一）燃油税制与现行客运企业经营管理模式的矛盾现有的客运经营主要实行线路或车辆租赁承包经营方式,     

低溶解氧污泥微膨胀污染物去除性能的研究

为了研究低溶解氧微膨胀状态下污染物的去除效果,采用SBR反应器,平均DO浓度为0.5～0.9 mg/L,通过好氧/缺氧(O/A)的运行方式,对污染物处理效果进行研究。结果表明：低溶解氧丝状菌污泥微膨胀状态下,SVI可稳定控制在200 mL/g左右,出水SS含量很低,COD去除率在80%以上,氨氮去除率90%以上,除磷效率在90%之上,出水水质良好,同时可以节约曝气量约46.7%。低溶解氧微膨胀状态下,可保证出水处理效果,污泥沉降性能影响小,同时可以节约动力费用。     

An analysis of extinction coefficients of particles and water moisture in the stack after flue gas desulfurization at a coal-fired power plant

Two important factors that affect in-stack opacity--light extinction by emitted particles and that by water moisture after a flue gas desulfurization (FGD) unit--are investigated. The mass light extinction coefficients for particles and water moisture, k(p) and k(w), respectively, were determined using the Lambert-Beer law of opacity with a nonlinear least-squares regression method. The estimated k(p) and k(w) values vary from 0.199 to 0.316 m2/g and 0.000345 to 0.000426 m2/g, respectively, and the overall mean estimated values are 0.229 and 0.000397 m2/g, respectively. Although k(w) is 3 orders of magnitude smaller than k(p), experimental results show that the effect on light extinction by water moisture was comparable to that by particles because of the existence of a considerable mass of water moisture after a FGD unit. The mass light extinction coefficient was also estimated using Mie theory with measured particle size distributions and a complex refractive index of 1.5-ni for fly ash particles. The k(p) obtained using Mie theory ranges from 0.282 to 0.286 m2/g and is slightly greater than the averaged estimated k(p) of 0.229 m2/g from measured opacity. The discrepancy may be partly due to a difference in the microstructure of the fly ash from the assumption of solid spheres because the fly ash may have been formed as spheres attached with smaller particles or as hollow spheres that contained solid spheres. Previously reported values of measured k(p) obtained without considering the effects of water moisture are greater than that obtained in this study, which is reasonable because it reflects the effect of extinction by water moisture in the flue gas. Additionally, the moisture absorbed by particulate matter, corresponding to the effect of water moisture on the particulates, was clarified and found to be negligible.     

Windsor, Ontario exposure assessment study: design and methods validation of personal, indoor, and outdoor air pollution monitoring

The Windsor, Ontario Exposure Assessment Study evaluated the contribution of ambient air pollutants to personal and indoor exposures of adults and asthmatic children living in Windsor, Ontario, Canada. In addition, the role of personal, indoor, and outdoor air pollution exposures upon asthmatic children's respiratory health was assessed. Several active and passive sampling methods were applied, or adapted, for personal, indoor, and outdoor residential monitoring of nitrogen dioxide, volatile organic compounds, particulate matter (PM; PM-2.5 pm [PM2.5] and < or =10 microm [PM10] in aerodynamic diameter), elemental carbon, ultrafine particles, ozone, air exchange rates, allergens in settled dust, and particulate-associated metals. Participants completed five consecutive days of monitoring during the winter and summer of 2005 and 2006. During 2006, in addition to undertaking the air pollution measurements, asthmatic children completed respiratory health measurements (including peak flow meter tests and exhaled breath condensate) and tracked respiratory symptoms in a diary. Extensive quality assurance and quality control steps were implemented, including the collocation of instruments at the National Air Pollution Surveillance site operated by Environment Canada and at the Michigan Department of Environmental Quality site in Allen Park, Detroit, MI. During field sampling, duplicate and blank samples were also completed and these data are reported. In total, 50 adults and 51 asthmatic children were recruited to participate, resulting in 922 participant days of data. When comparing the methods used in the study with standard reference methods, field blanks were low and bias was acceptable, with most methods being within 20% of reference methods. Duplicates were typically within less than 10% of each other, indicating that study results can be used with confidence. This paper covers study design, recruitment, methodology, time activity diary, surveys, and quality assurance and control results for the different methods used.     

Corrosion control when using passively treated abandoned mine drainage as alternative makeup water for cooling systems

Passively treated abandoned mine drainage (AMD) is a promising alternative to fresh water as power plant cooling water system makeup water in mining regions where such water is abundant. Passive treatment and reuse of AMD can avoid the contamination of surface water caused by discharge of abandoned mine water, which typically is acidic and contains high concentrations of metals, especially iron. The purpose of this study was to evaluate the feasibility of reusing passively treated AMD in cooling systems with respect to corrosion control through laboratory experiments and pilot-scale field testing. The results showed that, with the addition of the inhibitor mixture orthophosphate and tolyltriazole, mild steel and copper corrosion rates were reduced to acceptable levels (< 0.127 mm/y and < 0.0076 mm/y, respectively). Aluminum had pitting corrosion problems in every condition tested, while cupronickel showed that, even in the absence of any inhibitor and in the presence of the biocide monochloramine, its corrosion rate was still very low (0.018 mm/y).     

Enhanced nitrogen deposition exacerbates the negative effect of increasing background ozone in Dactylis glomerata, but not Ranunculus acris

The combined impacts of simulated increased nitrogen (N) deposition (75 kg N ha⁻¹ yr⁻¹) and increasing background ozone (O₃) were studied using two mesotrophic grassland species (Dactylis glomerata and Ranunculus acris) in solardomes, by means of eight O₃ treatments ranging from 15.5 ppb to 92.7 ppb (24 h average mean). A-C_i curves were constructed for each species to gauge effects on photosynthetic efficiency and capacity, and effects on biomass partitioning were determined after 14 weeks. Increasing the background concentration of O₃ reduced the healthy above ground and root biomass of both species, and increased senesced biomass. N fertilisation increased biomass production in D. glomerata, and a significantly greater than additive effect of O₃ and N on root biomass was evident. In contrast, R. acris biomass was not affected by high N. The study shows the combined effects of these pollutants have differential implications for carbon allocation patterns in common grassland species.