曝气生物滤池去除二级出水中的氨氮

用曝气生物滤池对二级出水进行深度处理,经过生物膜培养驯化、变负荷研究、稳定运行三个阶段,结果表明,二级出水中的氨氮能够有效去除,可以达到《地表水环境质量标准》(GB3838-2002)Ⅲ类水体标准,满足电厂循环冷却水及人工景观用水等高级回用的要求。     

外循环三相流化床污水处理特性的研究

采用三相外循环生物流化床处理生活污水。该设备包含好氧区和缺氧区,可获得足够的停留时间造成缺氧条件,能保证有效去除NH3—N。实验在室温下进行,进水条件pH为7～8,CODCr为286-656mg／L,NH3-N为10～51mg／L。结果显示,控制水力停留时间在3h为宜,最佳通气量为0．09m^3／h,此时CODc和NH3-N的去除率分别达91％和96．6％,有较好的处理效果。同时实验确定了最佳膜厚为145μm。     

膜生物法降解TNT弹药销毁废水的重要影响因素

采用水解酸化一好氧膜生物工艺对弹药销毁废水中TNT进行降解试验研究。结果表明,共代谢外加碳源对TNT的生物降解影响显著。无共代谢外加碳源的情况下,HRT=40h,TNT的去除率仅为53．4％。有共代谢外加碳源的情况下,外加碳源COD与TNT提供COD比值宜大于4．8,系统对TNT的去除率可高达99％。温度对水解酸化影响重大,当温度低于15℃时,水解酸化对TNT去除率低于33．3％,而当温度高于20℃时,水解酸化对TNT的去除率不小于83％。     

城市生活垃圾卫生填埋场恶臭的防治技术进展

恶臭污染已成为垃圾处理和处置过程中的严重公害。在分析中,介绍了填埋场各区域恶臭的控制措施,综述了卫生填埋场恶臭的常规防治技术,重点讨论了生物技术在填埋场脱臭中的应用,这些防治技术对各类环境卫生设施,如垃圾收集站、中转站、焚烧场、堆肥厂及粪便处理厂的臭气治理均有借鉴意义。     

生物流化床处理垃圾渗滤液的硝化强化实验研究

采用厌氧/好氧/硝化耦合生物流化床反应器处理高浓度难降解垃圾渗滤液,通过摇瓶富集与开放体系扩大培养得到高浓度的硝化菌液,用于硝化生物流化床反应器的挂膜启动、驯化与动态运行实验。结果表明,扩培菌液中亚硝化细菌与硝化细菌的浓度分别达到9 .0×107 和3. 5×107 MPN/mL。硝化生物流化床的强化挂膜启动与驯化约历时30d,实际废水动态运行的结果显示,当进水垃圾渗滤液平均氨氮浓度为284 .4mg/L时,出水氨氮浓度为14. 3mg/L,达到了GB16889 1997一级排放标准,经过硝化生物强化的流化床反应器处理高浓度垃圾渗滤液的硝化速率高达28. 1gNH+4 N/m3·h,与未经生物强化的同类系统相比高出近1倍。     

Clarifying values,risk perceptions,and attitudes to resolve or avoid social conflicts in invasive species management

Decision makers and researchers recognize the need to effectively confront the social dimensions and conflicts inherent to invasive species research and management. Yet, despite numerous contentious situations that have arisen, no systematic evaluation of the literature has examined the commonalities in the patterns and types of these emergent social issues. Using social and ecological keywords, we reviewed trends in the social dimensions of invasive species research and management and the sources and potential solutions to problems and conflicts that arise around invasive species. We integrated components of cognitive hierarchy theory and risk perceptions theory to provide a conceptual framework to identify, distinguish, and provide understanding of the driving factors underlying disputes associated with invasive species. In the ISI Web of Science database, we found 15,915 peer‐reviewed publications on biological invasions, 124 of which included social dimensions of this phenomenon. Of these 124, 28 studies described specific contentious situations. Social approaches to biological invasions have emerged largely in the last decade and have focused on both environmental social sciences and resource management. Despite being distributed in a range of journals, these 124 articles were concentrated mostly in ecology and conservation‐oriented outlets. We found that conflicts surrounding invasive species arose based largely on differences in value systems and to a lesser extent stakeholder and decision maker's risk perceptions. To confront or avoid such situations, we suggest integrating the plurality of environmental values into invasive species research and management via structured decision making techniques, which enhance effective risk communication that promotes trust and confidence between stakeholders and decision makers. Clarificar los Valores, Percepciones de Riesgo y Actitudes para Resolver o Evitar Conflictos Sociales en el Manejo de Especies Invasoras     

Resolving whether botanic gardens are on the road to conservation or a pathway for plant invasions

A global conservation goal is to understand the pathways through which invasive species are introduced into new regions. Botanic gardens are a pathway for the introduction of invasive non‐native plants, but a quantitative assessment of the risks they pose has not been performed. I analyzed data on the living collections of over 3000 botanic gardens worldwide to quantify the temporal trend in the representation of non‐native species; the relative composition of threatened, ornamental, or invasive non‐native plant species; and the frequency with which botanic gardens implement procedures to address invasive species. While almost all of the world's worst invasive non‐native plants occurred in one or more living collections (99%), less than one‐quarter of red‐listed threatened species were cultivated (23%). Even when cultivated, individual threatened species occurred in few living collections (7.3), while non‐native species were on average grown in 6 times as many botanic gardens (44.3). As a result, a botanic garden could, on average, cultivate four times as many invasive non‐native species (20) as red‐listed threatened species (5). Although the risk posed by a single living collection is small, the probability of invasion increases with the number of botanic gardens within a region. Thus, while both the size of living collections and the proportion of non‐native species cultivated have declined during the 20th century, this reduction in risk is offset by the 10‐fold increase in the number of botanic gardens established worldwide. Unfortunately, botanic gardens rarely implement regional codes of conduct to prevent plant invasions, few have an invasive species policy, and there is limited monitoring of garden escapes. This lack of preparedness is of particular concern given the rapid increase in living collections worldwide since 1950, particularly in South America and Asia, and highlights past patterns of introduction will be a poor guide to determining future invasion risks.     

What is the acceptable margin of error for the oxygen uptake method in evaluating the reactivity of organic waste?

The acceptable margin of error for the organic waste reactivity measured by the oxygen uptake method was assessed. Oxygen uptake was determined by the Dynamic Respiration Index (DRI) (mgO₂/kgVS h). The composed uncertainty (uC) of the experimental set up used for the DRI test was evaluated and the uncertainty (u) of all the components of the apparatus was evaluated. A procedure for calculating the uC of the apparatus is proposed. The components affecting the uC of the DRI to a more significant extent were the one of the oxygen mass rate and the u of the amount of VS in the sample analyzed. For a confidence level of 99.73%, the extended uC (UC) interval for a DRI = 1024 mgO₂/kgVS h was ±440 mgO₂/kgVS h, whereas for a DRI = 3489 mgO₂/kgVS h, the UC interval was ±1288 mgO₂/kgVS h. When oxygen consumption and VS content become lower than 600 mgO₂/h and 0.9 kg, respectively, the UC interval is similar to the measured DRI.     

生物除锰除铁滤池对低氟的去除效果研究

氟元素与人体健康关系比较密切,其含量过高和过低对人体健康都有危害,因而对地下水中氟污染物的研究,意义重大。为此人工配制了含F-为1．00～3．00mg／L、不同Mn2＋、Fe2＋浓度的原水,并通过已经培养成熟的生物除锰除铁滤池进行过滤。结果表明,进水pH（5．5～7．5）为中性条件下,滤池对氟具有长期稳定的微弱去除效果。在低pH（2．5—3．5）条件下,出水F-浓度在短时间内达到生活饮用水标准。     

PCR—DGGE技术在废水生物处理中的应用研究

聚合酶链式反应一变形梯度凝胶电泳（PCR—DGGE）作为一种分子指纹图谱能够较准确地反应污水处理过程中微生物群落结构多样性及其动态变化而广泛应用于废水生物处理技术的研究中。PCR—DGGE技术不仅能对样品中微生物群落结构多样性及种群演替进行分析,还能用于污水处理中优势菌群的分离与鉴定,克服了传统方法费时费力、培养条件苛刻等局限性,进而运用该技术构建高效的污染物降解工程菌,提高难降解有机物的去除效率,调节实际工艺参数,提高污水处理效率。