纳米级聚合氯化铝处理石化废水絮凝效果研究

采用自制的纳米级聚合氯化铝絮凝荆处理石大科技股份公司胜华炼油厂隔油池出水,以处理后水样的透光率作为混凝沉降效果的评价指标,并对絮凝剂投加量、搅拌速度、搅拌时间等影响混凝效果的因素进行了研究。试验表明,聚合氯化铝对石化废水的处理达到较为理想的效果,聚合氯化铝混凝处理石化废水的最佳条件为：纳米级聚合氯化铝投加量为15mg／L左右,慢速搅拌的搅拌速度为50～60rpm,快速搅拌的搅拌速度为190—225rpm,快速搅拌时间90s。慢速搅时间10min时效果最佳。使用Al-Ferron逐时络合比色法及XRD对絮凝荆进行了表征,结果证实样品中Alb含量可达到85％左右。     

基于光合色素的化学分类法在淡水藻类研究中的应用

采用反相高效液相色谱技术(RP HPLC)系统研究了我国主要淡水藻类--蓝藻、绿藻、硅藻、甲藻、金藻、裸藻和隐藻等的光合色素,在8种纯培养藻类中共确定类胡萝卜素、叶绿素及其衍生物19种。分离到的主要标志性色素按洗脱时间分别为脱植基叶绿素a、19′ 丁酰氧岩藻黄素、叶绿素c、脱镁叶绿素a、多甲藻素、甲基脱植基叶绿素a、岩藻黄素、新黄质、紫黄质、蓝藻叶黄素、硅甲藻黄素、硅藻黄质、叶黄素、玉米黄素、叶绿素b异构体、叶绿素b、叶绿素a异构体、叶绿素a和β 胡萝卜素;其中在纯培养的铜绿微囊藻中首次鉴定到19′ 丁酰氧岩藻黄素;通过官桥基地的实际监测,证实了该技术应用的可行性,为基于HPLC分析技术的浮游植物化学分类法提供了理论依据。     

Part V—sorption of pharmaceuticals and personal care products

Background, aim, and scope  Pharmaceuticals and personal care products (PPCPs) including antibiotics, endocrine-disrupting chemicals, and veterinary pharmaceuticals are emerging pollutants, and their environmental risk was not emphasized until a decade ago. These compounds have been reported to cause adverse impacts on wildlife and human. However, compared to the studies on hydrophobic organic contaminants (HOCs) whose sorption characteristics is reviewed in Part IV of this review series, information on PPCPs is very limited. Thus, a summary of recent research progress on PPCP sorption in soils or sediments is necessary to clarify research requirements and directions. Main features  We reviewed the research progress on PPCP sorption in soils or sediments highlighting PPCP sorption different from that of HOCs. Special function of humic substances (HSs) on PPCP behavior is summarized according to several features of PPCP–soil or sediment interaction. In addition, we discussed the behavior of xenobiotic chemicals in a three-phase system (dissolved organic matter (DOM)–mineral–water). The complexity of three-phase systems was also discussed. Results  Nonideal sorption of PPCPs in soils or sediments is generally reported, and PPCP sorption behavior is relatively a more complicated process compared to HOC sorption, such as the contribution of inorganic fractions, fast degradation and metabolite sorption, and species-specific sorption mechanism. Thus, mechanistic studies are urgently needed for a better understanding of their environmental risk and for pollution control. Discussion  Recent research progress on nonideal sorption has not been incorporated into fate modeling of xenobiotic chemicals. A major reason is the complexity of the three-phase system. First of all, lack of knowledge in describing DOM fractionation after adsorption by mineral particles is one of the major restrictions for an accurate prediction of xenobiotic chemical behavior in the presence of DOM. Secondly, no explicit mathematical relationship between HS chemical–physical properties, and their sorption characteristics has been proposed. Last but not least, nonlinear interactions could exponentially increase the complexity and uncertainties of environmental fate models for xenobiotics. Discussion on proper simplification of fate modeling in the framework of nonlinear interactions is still unavailable. Conclusions  Although the methodologies and concepts for studying HOC environmental fate could be adopted for PPCP study, their differences should be highly understood. Prediction of PPCP environmental behavior needs to combine contributions from various fractions of soils or sediments and the sorption of their metabolites and different species. Recommendations and perspectives  More detailed studies on PPCP sorption in separated soil or sediment fractions are needed in order to propose a model predicting PPCP sorption in soils or sediments based on soil or sediment properties. The information on sorption of PPCP metabolites and species and the competition between them is still not enough to be incorporated into any predictive models.     

Perfluorosulfonates and perfluorocarboxylates in snow and rain in Dalian,China

Samples of precipitation events (snow and rain) in Dalian, a typical coastal town in China, were analyzed for perfluorosulfonates (PFSAs) and perfluorocarboxylates (PFCAs) to investigate atmospheric contamination by these compounds. In the snow event on December 16, 2006, samples were collected from 21 different sites and in another 6 precipitation events, samples were collected from a single location. Four PFSAs (C4, C6, C8, C10) and seven PFCAs (C6–12) were analyzed. Among the homologues, perfluorooctane sulfonate (PFOS) concentrations were the highest with a geometric mean (GM) of 145 ng/L (n = 21) during the snow event on December 16, 2006, followed by perfluorooctanoate (PFOA) with a GM of 24.7 ng/L (n = 21). Concentrations of perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS) and perfluoroheptanoate (PFHpA) were more than two orders of magnitude lower than that of PFOS. Other PFSAs and PFCAs were found to be below the limit of detection in all the samples. In other 6 precipitation events, PFSAs and PFCAs were detected approximately in the same order of magnitude in both snow and rain. The results indicate that wet deposition may be a potential transport mechanism of perfluorinated chemicals in the environment.     

Research on the Industrial Symbiosis Supporting System of Eco-industrial Park

The establishment and development of the industrial symbiosis of eco-industrial park are affected by several factors. Based on the formed industrial symbiosis supporting system chart, this article analyzes the microcosmic supporting system and macroscopic supporting system. In the microcosmic supporting system, it elaborates five aspects including key enterprises, service intermediaries in the park, symbiotic enterprises, competitors and the public in detail. Then it describes the macroscopic supporting system from four aspects of governmental participation, technological innovation, educational promotion and cultural support. Finally, combining with the current construction status of the ecoindustrial park in China, it proposes the countermeasures and suggestions to build the supporting system for the eco-industrial park and provides theoretical support for the faster and better construction of the eco-industrial park in China.     

Cation exchange in a glacial till drumlin at a road salt storage facility

At a former wood preservation plant severely contaminated with coal tar oil, in situ bulk attenuation and biodegradation rate constants for several monoaromatic (BTEX) and polyaromatic hydrocarbons (PAH) were determined using (1) classical first order decay models, (2) Michaelis–Menten degradation kinetics (MM), and (3) stable carbon isotopes, for o-xylene and naphthalene. The first order bulk attenuation rate constant for o-xylene was calculated to be 0.0025 d^− 1 and a novel stable isotope-based first order model, which also accounted for the respective redox conditions, resulted in a slightly smaller biodegradation rate constant of 0.0019 d^− 1. Based on MM-kinetics, the o-xylene concentration decreased with a maximum rate of k_max = 0.1 µg/L/d. The bulk attenuation rate constant of naphthalene retrieved from the classical first order decay model was 0.0038 d^− 1. The stable isotope-based biodegradation rate constant of 0.0027 d^− 1 was smaller in the reduced zone, while residual naphthalene in the oxic part of the plume further downgradient was degraded at a higher rate of 0.0038 d^− 1. With MM-kinetics a maximum degradation rate of k_max = 12 µg/L/d was determined. Although best fits were obtained by MM-kinetics, we consider the carbon stable isotope-based approach more appropriate as it is specific for biodegradation (not overall attenuation) and at the same time accounts for the dominant electron-accepting process. For o-xylene a field based isotope enrichment factor ε_field of − 1.4 could be determined using the Rayleigh model, which closely matched values from laboratory studies of o-xylene degradation under sulfate-reducing conditions.     

针铁矿对Pb~(2+)的吸附特征及影响因素研究

通过恒温振荡平衡法研究了Pb~(2+)在针铁矿上的等温吸附和吸附动力学特征,探讨了吸附的影响因素.结果表明:(1)随Pb~(2+)平衡浓度和pH的增大,针铁矿对Pb~(2+)的吸附量逐渐增大.(2)针铁矿对Pb~(2+)的等温吸附可用Freundlich和Langmuir方程较好地拟合.(3)在相同温度和pH下,随离子强度的提高,针铁矿对Pb~(2+)的吸附量增大.(4)在相同离子强度和pH下,针铁矿对Pb~(2+)的吸附量总体随温度升高而增大.针铁矿对Pb~(2+)的吸附是自发进行的吸热反应.(5)针铁矿吸附Pb~(2+)的过程可分为初始的快吸附和随后的慢吸附2个阶段.pH影响吸附反应快慢,随pH增大吸附速率增大;随着pH的增大,达到平衡吸附的时间缩短.吸附动力学方程用Elovich方程拟合最佳.     

伞罩型湿式脱硫除尘塔入口结构优化模拟

利用商用CFD软件Fluent,采用k-ε湍流模型和SIMPLE算法,对新型伞罩型湿式脱硫除尘塔内的三维两相流场进行数值模拟,发现了塔内烟气入口处流场所存在的不均匀性。为将其流场调节均匀从而提高脱硫除尘效率,在数值模拟的基础上提出在入口处加装直导流板、阶梯导流板和弯曲导流板,并分析塔内y=0截面速度的分布,以及z＝0.21 m截面上的颗粒浓度、速度和压力等参数的分布。结果表明：通过加装阶梯导流板和弯曲导流板均可以将流场调节均匀,达到较理想状态,从而实现高效净化气体的目的。模拟结果对设备的优化设计和实际运行有一定的指导作用。     

三氯生在碳纳米管上的吸附

药品和个人护理用品(PPCPs)已成为一个引起广泛关注的新的环境问题。采用碳纳米管（CNTs）对水溶液中的三氯生进行吸附处理,考察了碳纳米管粒径及用量、温度、pH、振荡时间等因素对三氯生去除率的影响。研究结果表明,碳纳米管能快速吸附水中的三氯生,粒径较小的碳纳米管可获得较高的三氯生去除率;低温有利于吸附反应的进行;pH在6.5～7.0时,三氯生的去除率可达97%。三氯生在碳纳米管上的吸附可以很好地用Langmuir和Freundlich吸附等温方程进行描述。     

污泥活性炭强化SBR法处理垃圾渗滤液的实验研究

为了进一步处理垃圾渗滤液,试验采用污泥活性炭强化序批式间歇反应器（SBR）法进行处理,通过对比普通SBR法试验,得出投加污泥活性炭强化SBR法处理垃圾渗滤液的效果要远远高于普通SBR法。当污泥活性炭的投加量为1.2 g/L,容积负荷为0.5～1.5 kg BOD₅/(m³·d)时,进水1 h,曝气10 h,沉淀1.5 h,闲置1.5 h,处理效果最好,COD的去除率达到了85%,NH³-N的去除率达到了90%。