聚丙烯纤维组合填料在CAST水处理工艺中的运用

西南某市小型污水处理厂目前日处理能力为2万t.d-1,进水主要为生活污水(70%)和抗生素制药废水(30%)。由于各种原因,处理效果一直很差,尤其是CODcr、NH4-N两项指标很难达到国家排放标准要求。后经过一系列实验研究分析,发现向反应池中投加聚丙烯纤维(组合填料)对处理水质起到了很好的改善作用。     

磁混凝澄清工艺在污水厂提标中的应用

磁混凝澄清工艺是在常规混凝工艺中投加磁粉,磁粉微小有利于混凝絮体生成。介绍了磁混凝澄清工艺的原理及技术特点,并实际应用于一级A提标工程,结果表明,磁混凝澄清池表面水力负荷可达20~40 m3/m2·h,同时出水SS5 mg/L,浊度1.0 NTU,TP0.02 mg/L,非常适合于城市污水厂提标。     

气田压裂返排液氧化处理实验研究

以四川某气田压裂返排液为研究对象,采用破胶絮凝处理后进行氧化对比实验,氧化剂选用高锰酸钾、过硫酸钾、次氯酸钠、Fenton试剂。研究表明,絮凝实验最佳条件为氧化钙、硫酸铝和硫酸亚铁投加量分别为3,1,1 g/L。4种氧化方法的最佳实验条件为:高锰酸钾投加量0.5 g/L,pH值为4;过硫酸钾投加量0.25g/L,pH值为6;次氯酸钠投加量15 g/L,pH值为4;Fenton氧化方法pH值为3.5,双氧水投加量25 g/L,七水硫酸亚铁投加量10 g/L。出水COD_(Cr)最多可降至800 mg/L左右,最大COD_(Cr)去除率72.96%,处理效果良好,为后续处理创造了条件。     

2012年国家鼓励发展的环境保护技术（二）

超磁分离水体净化技术技术依托单位：四川环能德美科技股份有限公司中图分类号：X703文献标志码：B文章编号：1006-5377（2012）11-0061-01工艺路线该技术在废水中投加磁粉、混凝剂、助凝剂,形成磁粉为核心的絮体,再利用磁性材料将废水中的磁性体分离出来,实现水体的净化。磁粉回收循环利用。主要技术指标SS和总磷去除率大于95%。适用范围适用于含悬浮物浓度高的污水处理。     

高锰酸钾预氧化强化微污染水源水中锰的去除

目前,我国很多地区地表水都存在锰超标问题,这给供水安全带来了极大隐患.本文考察了高锰酸盐预氧化强化水中锰的去除效果.实验结果表明,原水经过高锰酸盐处理后,水中的锰含量明显降低,当高锰酸盐投加量达到0.5mg/L之后,水中的锰离子浓度已经达到了原子吸收检出限以下,但色度有所增加.当高锰酸钾∶硫酸亚铁=1∶4时,水中的锰去除效果较好,色度降低,随着亚铁离子投加比例的增加,水中锰的去除率反而下降.     

混凝剂在再生水深度处理中的实验研究

选用硫酸亚铁、三氯化铁、聚合氯化铝、硫酸铝4种混凝剂进行再生水深度处理实验,考察铁盐类和铝盐类混凝剂对二级出水中浊度和UV254的去除效果,以及对三氯甲烷与四氯化碳的控制效果。在投加量为40 mg/L时,聚合氯化铝对浊度和UV254处理效果最好;对氯化消毒中三氯甲烷生成量控制效果最好的是三氯化铁,其次是硫酸亚铁;聚合氯化铝对四氯化碳的控制效果最好,且投加量在10 mg/L时,四氯化碳生成量达到最低。     

黄浦江上游原水强化处理选炭试验研究

以黄浦江上游水源为原水,通过煤质炭、竹质炭、椰壳炭等炭种筛选小试和中试试验,研究了黄浦江上游原水中有机污染物强化去除的最佳炭种及其最佳投加量。结果表明黄浦江上游原水中投加PAC能够改善处理后水质,提高原水中有机物的去除效果;并且随着PAC投加量的增加,原水中有机物去除效果增强;综合性价比、碳源等因素确定竹质炭较为经济合理;当竹质炭投加量为10～15mg/L时,处理后出水CODMn可达到3mg/L或以下。     

冷轧废乳化液混凝破乳试验研究

试验针对某冷轧带钢公司的废乳化液,研究了聚合硫酸铁(PFS)、聚合氯化铝(PAC)、硫酸铁[Fe_2(SO_4)_3·7H_2O]、硫酸亚铁(FeSO_4·7H_2O)对废乳化液的混凝-上浮影响。实验结果表明,4种混凝剂对破乳效果均较好,综合考虑絮体状态、处理效果及成本,确定硫酸亚铁为本试验的最佳药剂。试验温度为实验季节水温,温度为20℃左右。最佳试验条件为:硫酸亚铁投加量为4 g/L,PAM投加量为0.04 g/L,pH=8,此时COD去除率为95.2%,油去除率为96.7%。     

活性炭在膜生物反应器中的应用研究进展

活性炭是一种非常优良的吸附剂，具有物理吸附和化学吸附的双重特性。本文介绍了近年来向膜生物反应器中投加活性炭的应用研究进展，表明投加活性炭可以提高膜生物反应器的处理效果，同时对改善膜污染有很好的效果。     

纤维转盘微滤布污水过滤技术

<正>由浦华环保有限公司开发的纤维转盘微滤布污水过滤技术,适用于废水的深度处理与中水回用。主要技术内容一、基本原理采用微滤布过滤结合化学加药方法去除二级处理出水中的总磷。化学除磷通过化学沉析过程和化学絮凝作用完成。向污水中投加溶解性的金属盐药剂后,溶解性的磷转换成为非溶解性的磷酸金属盐,同时也会产生非     

AN APPLICATION RUNOFF MODEL STRATEGY FOR UNGAGED WATERSHEDS1

ABSTRACT: Mathematical models for predicting watershed surface flow responses are available, most of which are elaborate nonlinear numerical surface and channel flow models linked with infiltration models. Such models may be used to make predictions for ungaged areas, assuming an acceptable fitting of the model to the topography and roughness of the real system. For some application purposes, these models are impractical because of their complexity and expensive computer solutions. A procedure is developed that uses a complex model of an ungaged area to derive a simpler parametric nonlinear system model for repetitious simulation with input sequences. The predicted flow outputs are obtained with the simpler model at significant savings of money and time. The procedures for constructing a complex kinematic model of a 40 acre (161,880 m²) reference watershed and deriving the simpler system model are outlined. The results of predictions from both models are compared with a selected set of measured events, all having essentially the same initial conditions. Peak discharges ranged from 3 to 118 ft³/sec (0.085 to 3.34 m³/sec), which includes the largest event of record. The inherent limitations of lumped systems models are demonstrated, including the bias caused by their inability to model infiltration losses after rainfall ceases. Computer costs and times for the models were compared. The derived simple model has a cost advantage when repeated use of a model is required. Such an applications hydrologic model has an engineering tradeoff of reduced accuracy, and lumping bias, but is more economical for certain design purposes.     

Conversion of temperate forests into heaths: Role of ecosystem disturbance and ericaceous plants

Fire and logging in nutrient-poor temperate forests with certain ericaceous understory plants may convert the forests into heaths. The process of disturbance-induced heath formation is documented by using examples ofCalluna in western Europe,Kalmia in Newfoundland, andGaultheria (salal) in coastal British Columbia. In a cool, temperate climate, rapid vegetative growth ofCalluna, Kalmia, and salal following disturbance results in increasing organic accumulation (paludification), nutrient sequestration, soil acidification, and allelochemicals. These are thought to be the main reasons to conifer regeneration failure in disturbed habitats. If continuation in forest is a land-use objective, then temperate forests with an ericaceous understory should not be logged unless effective silvicultural methods are devised to control the ericaceous plants and restore forest regeneration. Preharvest vegetation control may be considered as an option. Failure to control the understory plants may lead to a long-term vegetation shift, from forest to heathland, particularly in nutrient-poor sites. Successful methods of controllingKalmia andGaultheria, however, have yet to be developed. While theKalmia- andGaultheria- dominated heathlands are undesirable in Canada and the Pacific Northwest, a wide range ofCalluna heathlands of western Europe are being conserved as natural and seminatural vegetation.     

Using Paleo Reconstructions to Improve Streamflow Forecast Lead Time in the Western United States

In water stressed regions, water managers are exploring new horizons that would help in long‐range streamflow forecasts. Oceanic‐atmospheric oscillations have been shown to influence streamflow variability. In this study, long‐lead time streamflow forecasts are made using a multiclass kernel‐based data‐driven support vector machine (SVM) model. The extended streamflow records based on tree ring reconstructions were used to provide a longer time series data. Reconstructed data were used from 1658 to 1952 and the instrumental record was used from 1953 to 2007. Reconstructions for oceanic‐atmospheric oscillations included the El Niño‐Southern Oscillation, Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation, and North Atlantic Oscillation. Streamflow forecasts using all four oscillations were made with one‐year to five‐year lead times for 21 gages in the western United States. This is the first study that uses both instrumental and reconstructed data of oscillations in SVM model to improve streamflow forecast lead time. SVM model was able to provide “satisfactory” to “very good” forecasts with one‐ to five‐year lead time for the selected gages. The use of all the oscillation indices helped in achieving better predictability compared to using individual oscillations. The SVM modeling results are better when compared with multiple linear regression model forecasts. The findings are statistical in nature and are expected to be useful for long‐term water resources planning and management.     

Urban ecological systems: scientific foundations and a decade of progress

Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.     

Neighbourhood characteristics and urban gardens in the Toledo metropolitan area: staffing and voluntarism,food production,infrastructure, and sustainability practices

Urban gardens are important sources of sustenance for communities with limited access to food. Hence, this study focuses on food production in gardens in the Toledo metropolitan area in Northwest Ohio. We administered surveys to 150 garden managers from November 2014 to February 2015 in our attempt to better understand how neighbourhood racial composition and poverty levels are related to staffing and voluntarism, food production and distribution, the development of infrastructure, and the adoption of sustainability practices in urban gardens. The results from 30 gardens are presented in this paper. We used Geographic Information Systems to map the gardens and overlay the map with 2010 census data so that we could conduct demographic analyses of the neighbourhoods in which the gardens were located. Though the gardens were small – two acres or less – up to 46 varieties of food were grown in a single garden. Gardens also operated on small budgets. Food from the gardens was gifted or shared with friends, family, and neighbourhood residents. Gardens in predominantly minority neighbourhoods tended to have fewer institutional partners, less garden infrastructure, and had adopted fewer sustainable practices than gardens in predominantly White neighbourhoods. Nonetheless, residents of predominantly minority and high-poverty neighbourhoods participated in garden activities and influenced garden operations. Volunteering and staffing were racialised and gendered.     

Predicting deer-vehicle collisions in an urban area

Collisions with deer and other large animals are increasing, and the resulting economic costs and risks to public safety have made mitigation measures a priority for both city and wildlife managers. We created landscape models to describe and predict deer-vehicle collision (DVCs) within the City of Edmonton, Alberta. Models based on roadside characteristics revealed that DVCs occurred frequently where roadside vegetation was both denser and more diverse, and that DVCs were more likely to occur when the groomed width of roadside right-of-ways was smaller. No DVCs occurred where the width of the vegetation-free or manicured roadside buffer was greater than 40 m. Landscape-based models showed that DVCs were more likely in more heterogeneous landscapes where road densities were lower and speed limits were higher, and where non-forested vegetation such as farmland was in closer proximity to larger tracts of forest. These models can help wildlife and transportation managers to identify locations of high collision frequency for mitigation. Modifying certain landscape and roadside habitats can be an effective way to reduce deer-vehicle collisions.     

BIOLOGICAL INDICATORS AND BIOLOGICAL EFFECTS OF ESTUARINE/COASTAL POLLUTION1

ABSTRACT: Sustained interest in and concern about the health status of the aquatic environment has resulted in extensive research focused on (1) effects of pollution on survival, growth, and reproduction of resource species at all life stages; (2) diseases of fish and shellfish, as they may be related to pollution and as they may serve as indicators of environmental stress; and (3) contaminant body burdens in fish and shellfish - their effects on the aquatic animals and their potential effects on humans. Effects, lethal and sublethal, of pollutants on life history stages of fish and shellfish have been documented, as have impacts on local stocks in badly degraded habitats, but as yet there has been no adequate quantitative demonstration of effects on entire aquatic species - probably because of the difficulty in sorting out relative effects of the many environmental factors that influence abundance. Sublethal effects, especially those that result in disease, have been examined intensively, and some diseases and disease syndromes have been associated statistically with pollution. Other pollution indicators (biochemical, physiological, genetic, behavioral, and ecological) have also received some attention, as have body burdens of contaminants in aquatic species. Research, especially that conducted during the past decade, has done much to clarify the many pathways and toxic effects of contaminants on aquatic animals, and has also helped to identify mechanisms for survival of fish and shellfish in the presence of environmental changes caused by human activities.     

Biodiversity and biotechnology

The maintenance of biodiversity is urged from many quarters and on grounds ranging from aesthetic considerations to its usefulness, particularly for biotechnology. But regardless of the grounds for preserving biodiversity, writers are generally in agreement that it should be preserved. But, in examining the various references biodiversity, such as species diversity, genetic diversity, and habitat diversity, it is apparent that we cannot aim to preserve biodiversityas such, since there are a number of conflicts in any such undertaking. In preserving one aspect of biodiversity, we damage another aspect. Five arguments which attempt to ground our moral concern for biodiversity are reviewed and critiqued, not only for their consistency but also for their power to move us to action. The final section of the paper shows how conflicts in the values of personal and environmental health can impair ethical action and especially policy formation.An earlier version of this paper was read at the conference on Agriculture, Food, and Human Values: Tradition and Change, Orlando, Florida, October 7–9, 1987.     

Journalists' views of advertiser pressures on agricultural news

All major journalism ethical codes explicitly state that journalists should protect editorial copy from undue influence by outside sources. However, much of the previous research on agricultural information has concentrated on what information various media communicate (gatekeeping studies) or communication's role in increasing innovation adoption (diffusion studies). Few studies have concentrated specifically on organizational and structural constraints that might adversely affect agricultural journalists' ethical standards; those that have, focus largely on farm magazines. A study of newspaper reporters who cover agricultural news found that the most pressing ethical concern is the effect of advertiser (agri-business) pressure on editorial copy, and that their concerns in general parallel those of farm magazine writers and editors. The majority reported being in situations in which they might be exposed to advertiser pressure, including pressures to change or withhold editorial copy. Large minorities suggested that advertising pressures affect the overall environment in which agricultural journalists work, and more than one in ten said they allow advertiser pressures to influence editorial decisions. The newspaper reporters who cover agricultural beats showed slightly more resistance to advertiser pressure than did farm magazine editors in a parallel study.     

Definition Procedures Have Little Effect on Performance of Environmental Classifications of Streams and Rivers

Mapped environmental classifications are defined using various procedures, but there has been little evaluation of the differences in their ability to discriminate variation in independent ecological characteristics. We tested the performance of environmental classifications of the streams and rivers of France that had been defined from the same environmental data using geographic regionalization and numerical classification of individual river valley segments. Test data comprised invertebrate assemblages, water chemistry, and hydrological indexes obtained from sites throughout France. Classification performance was measured by analysis of similarity (ANOSIM). Geometric regions defined by a regular grid and without regard to environmental variables and a posteriori classifications based on clustering the test datasets defined lower and upper bounds of performance for a given number of classes. Differences in classification performances were generally small. The ANOSIM statistics for the a posteriori classifications were around twice that of all environmental classifications, including geometrically defined regions. The hydro-ecoregions performed slightly better for the invertebrate data and the network classification performed slightly better for the chemistry and hydrological data. Our results indicate that environmental classifications that are defined using different procedures can be comparable in terms of their ability to discriminate variation of ecological characteristics and that alleged differences in performance arising from different classification procedures can be small relative to unexplained variation. We conclude that definition procedures might have little effect on the performance of large-scale environmental classifications and decisions over which procedures to use should be based primarily on pragmatic considerations.