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1.
阐述了磷形态的不同分类方法及磷的形态、水生生物、温度、pH值、溶解氧和扰动等因素对湖泊沉积层磷释放的影响,并对植物修复富营养化湖泊的机理和影响植物修复的环境因素进行了探讨和分析,指出在加强控制外源污染的同时,因地制宜,选择适宜的水生植物种类,对湖泊进行植物修复,逐步恢复湖泊的自然净化能力,可有效抑制湖泊富营养化。  相似文献   

2.
阐述了反硝化除磷的机理,对现有反硝化除磷工艺进行介绍,并进一步讨论了反硝化除磷的影响因素和未来发展新思路。利用DPBs进行反硝化除磷实现了污水处理的资源化和能源化,代表了当前污水处理可持续发展战略的发展趋势,成为目前脱氮除磷技术研究的热点和重点。  相似文献   

3.
利用反硝化聚磷菌实现城市污水的脱氮除磷   总被引:4,自引:0,他引:4  
刘国全 《四川环境》2009,28(2):91-95
阐述了反硝化除磷的机理,对现有反硝化除磷工艺进行介绍,并进一步讨论了反硝化除磷的影响因素和未来发展新思路。利用DPBs进行反硝化除磷实现了污水处理的资源化和能源化,代表了当前污水处理可持续发展战略的发展趋势,成为目前脱氮除磷技术研究的热点和重点。  相似文献   

4.
废水除磷方法与原理的研究进展   总被引:4,自引:0,他引:4  
介绍了污水的各种常用除磷技术方法及原理,为不同条件下的污水除磷提供参考与选择的依据,并探讨了除磷技术的发展趋势。  相似文献   

5.
本文分析了城市污水中磷的来源、形态和数量以及磷在污水处理过程中的走向和生物化学变化,提出了几种提高除磷率的方法,并特别介绍了用铝酸钙渣作吸附荆除磷的方法。  相似文献   

6.
本文通过常用的三类除磷药剂(铁盐、铝盐、钙盐)对金属涂装业中含磷废水处理效果的比较,选定该类型含磷废水的处理药剂为氯化钙;并讨论了药剂投加量及投加点的控制对于废水的除磷效果以及日后使用效果的影响.  相似文献   

7.
除磷微生物和新型除磷工艺   总被引:3,自引:1,他引:3  
本文总结了聚磷微生物的微生物学、分子生物学、生化动力学,生物除磷的影响因素,并进一步探讨了一些能够在不利的环境条件下实现除磷的新型生物除磷脱氮工艺,以及如何实现除磷的最佳化。对聚磷微生物的筛选和驯化以及遗传改良将有助于进一步开发高效的生物除磷工艺,磷的资源化回收利用和再循环将是今后研究的前沿。  相似文献   

8.
缺氧反应时间对反硝化除磷系统脱氮除磷效果的影响   总被引:4,自引:0,他引:4  
反硝化除磷工艺具有节省碳源、曝气量以及污泥产量低等优点,因而在处理城市生活污水中具有显著优势。反硝化除磷效能主要在缺氧阶段完成。缺氧时间直接影响系统的脱氮除磷效率。本实验以SBR反应器在厌氧/缺氧/好氧条件下富含的反硝化聚磷菌(DPAOs)为研究对象,通过调节不同的缺氧反应时间(150 min,210 min和270 min),考察缺氧反应时间冲击对下一周期代谢的影响和长期对整个反硝化除磷系统的影响。冲击实验发现:缺氧时间的改变基本不影响下一周期挥发性脂肪酸(VFAs)的吸收以及硝氮去除。在长期缺氧反应时间不同的系统中,当缺氧时间分别为150 min、210 min和270 min时,除磷效率分别是-10.4%、62.5%、73.6%,脱氮率均达到100%。当缺氧反应时间从150 min延长到270 min时,微生物体内聚羟基脂肪酸酯(PHAs)水平和聚磷(poly-P)水平以及释磷量都升高。实验表明,缺氧时间的适当延长利于提高除磷效率。  相似文献   

9.
含磷废水处理药剂的选定及讨论   总被引:1,自引:0,他引:1  
本文通过常用的三类除磷药剂(铁盐、铝盐、钙盐)对金属涂装业中含磷废水处理效果的比较,选定该类型含磷废水的处理药剂为氯化钙;并讨论了药剂投加量及投加点的控制对于废水的除磷效果以及日后使用效果的影响。  相似文献   

10.
三级SBR法除磷脱氮研究   总被引:2,自引:0,他引:2  
基于除磷脱氮的原理和环境要求提出三级SBR法的污水处理工艺。特点是将具有硝化、聚磷和去碳功能的细菌种群分别控制在三级反应器中以利于各类菌群能优势生长。与单级处理系统比较不仅提高效率并可以减少能耗,节约碳源。  相似文献   

11.
The Copper Basin is located within the southern Appalachian Mountains primarily in extreme southeastern Tennessee, USA. It has long been known for its copper mining/smelting and associated chemical industry, as well as its severely injured environment. Virtually all previous commentary on the environmental degradation at this location have focused on human activities and their destructive impact. This article approaches the subject from a different angle, one that emphasizes the interaction between man and nature. The site's physical setting, industrial history, and environmental history are briefly reviewed. The theory then presented here is that certain of the Copper Basin's natural features made its environment unusually vulnerable to the negative impact of copper mining and smelting, especially as practiced around the turn of the century. These features are identified. This reasoning provides the basis for the concept of environmental susceptibility, which is defined and discussed. A few of its applications are mentioned. This study offers a new perspective on the Copper Basin, as well as insights for those whose work involves investigating the man/nature relationship—both past and present.  相似文献   

12.
Industry's role in environmental protection is changing and growing. Increasing evidence shows that a corporation's understanding and response to environmental issues and concerns can have strategically important consequences for some kinds of businesses.1 Focusing on concepts of prevention, industry has developed and struggled with a number of environmental approaches, all of which attempt to link the environment with common business practice. Industry has followed and in some cases embraced concepts and approaches like sustainable development, eco-efficiency, green manufacturing, pollution prevention, and extended product responsibility. A particularly timely and promising strategy to reduce the environmental impact of both manufacturing and product use while enhancing business success is the integration of environmental management systems (EMS) with design for the environment (DFE) efforts. A desirable relationship can and should exist between DFE and EMS. This relationship has not been well understood, but is crucial to fulfill the promise of each. In application, the institutionalization of DFE in an organization is difficult and tenuous at best. Some authors suggest that management issues block the implementation of DFE.2 Others say that DFE has not been institutionalized to the extent that pollution prevention has.3 This article suggests that through an explicit connection between an EMS and DFE, DFE can extend the promise of EMS to reduce industry's environmental impact and produce business success, and it can do so in an ongoing way. The authors will show the importance of an EMS/DFE linkage, suggest company types that might benefit from investigating these approaches, and then review a series of DFE tool types.  相似文献   

13.
针对目前天然气勘探开发项目环境影响评价不够系统的局限性,运用系统的思想观点和思维方法提出了天然气勘探开发项目综合环境影响评价指标体系.该评价体系把综合环境影响评价分为政策法规环境影响、自然生态环境影响、资源能源环境影响、经济环境影响、社会环境影响和科技环境影响等六大环境影响进行评价.借鉴环境影响评价的相关研究成果,分别为上述六大环境影响评价设计了具体的评价因子和评价指标.  相似文献   

14.
Treatment of risk in environmental impact assessment   总被引:7,自引:0,他引:7  
Risk assessment and environmental impact assessment have developed as separate traditions. While environmental impact assessment is a broad field that includes all activities that attempt to analyze and evaluate the effects of human and related actions on the environment, risk assessment has been concerned with the relatively well-defined regulatory problems and employs formal quantitative analysis of the probability of specific undesired events, such as cancer. Risk analytic approaches, particularly the explicit treatment of uncertainty, can significantly contribute to environmental assessments. This article discusses the type and sources of uncertainty in environmental assessments, techniques for their quantification, and ways to use uncertainty estimates to calculate probabilities of effects or probabilities of exceeding environmental standards and to determine the need for mitigation or additional research.This article was presented at the International Institute of Applied Systems Analysis, Task Force Meeting on Risk and Policy Analysis under Conditions of Uncertainty, Laxenburg, Austria, November 1985.  相似文献   

15.
Cost effective feeding strategies are essential to deal with P surpluses associated with intensive animal agriculture and the consequent impact on water quality. Reduction of P overfeeding, use of feed additives to enhance dietary P utilization, and development of high available phosphorus (HAP) grains have all been shown to decrease fecal P excretion without impairing animal performance. Much progress has been made, but more research will be needed to refine these strategies to maximize reductions in P excretion while maintaining animal performance. Recent research has focused on the impact of modifying dietary P on the forms of P excreted and the mobility of P in soils amended with these manures, with strong treatment trends becoming evident in the literature. In general, dietary strategies have been developed that can effectively reduce the total P concentration in manures produced, and combining strategies usually leads to greater reductions than individual practices. However, the impact of different approaches on the solubility of P in manures and amended soils has been more variable. Soluble P remains of particular concern due to links between solubility of P in manure and P losses from manure-amended soils. In this paper, we outline the major strategies for reducing dietary P in different species, review the literature on the impact of these approaches on P forms in manures and amended soils, and discuss the potential beneficial effects on animal agriculture and the environment.  相似文献   

16.
Nnewi is situated some 30 kilometres South East of Onitsha in Anambra State in the southeastern part of Nigeria. This highly commercial town has undergone rapid urbanisation and industrialisation within the past two decades, since the end of the 1967–1970 Nigerian civil war. The Igbo community of the study area had traditionally employed bioconversion methods and other indigenous technology to process or recycle bio and non-degradable wastes. Industrialisation has enjoyed priority status in this locality as a requirement for modernisation and economic progress. The rapid urbanisation, aggressive industrialisation, and the attendant uncontrolled population growth have had a deleterious impact on the environment. There is now a wide range of industrial wastes that are released daily into the environment. Effects of these activities on the socio-cultural practices of the people, plant genetic resources and the environment are highlighted. In addition to palliative measures suggested here, a call is made to revisit the successful indigenous waste treatment and management technology formerly practised by the Igbo community. The importance of combining modern biotechnological approaches with the indigenous technology, norms and practices of Nwewi people to effect suitable waste treatment and management, as well as improving the living habits and the education of the people about their environment, is recommended. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

17.
本文通过大气污染对生态环境影响的途径分析,立足于生态环境影响区划,提出一种估算大气污染对生态环境影响损失的方法,并应用于一项环境影响评价,其结论更为具体,明确。  相似文献   

18.
Nickel is an important metal, heavily utilized in industry mainly due to its anticorrosion properties. As a consequence, nickel containing wastes such as spent batteries and catalysts, wastewater and bleed-off electrolytes are generated in various processes. These wastes could have a negative impact on the environment and human health if they contaminate soil, water and air. The present review addresses the environmental and economical aspects of nickel recovery/removal from various types of wastes. The main physico-chemical technologies for processing various effluents and wastewaters containing nickel are reviewed and discussed. Nickel recovery from spent batteries, catalysts, electronic waste and other sources is described. Hydrometallurgical approaches are emphasized. Recovery of nickel from wastes is important not only for economical aspects, but also for environmental protection.  相似文献   

19.
Lack of standard methods for quantifying impact has hindered risk assessments of high-impact invaders. To understand methodological strengths and weaknesses, we compared five approaches (in parentheses) for quantifying impact of nonnative fishes: reviewing documented impacts in a large-scale database (review); surveying fish biologists regarding three categories of impact (socioeconomic, ecological, abundance); and estimating frequency of occurrence from existing collection records (collection). In addition, we compared game and nongame biologists’ ratings of game and nongame species. Although mean species ratings were generally correlated among approaches, we documented important discrepancies. The review approach required little effort but often inaccurately estimated impact in our study region (Mid-Atlantic United States). Game fishes received lower ratings from the socioeconomic approach, which yielded the greatest consistency among respondents. The ecological approach exhibited lower respondent bias but was sensitive to pre-existing perceptions of high-impact invaders. The abundance approach provided the least-biased assessment of region-specific impact but did not account for differences in per-capita effects among species. The collection approach required the most effort and did not provide reliable estimates of impact. Multiple approaches to assessing a species’ impact are instructive, but impact ratings must be interpreted in the context of methodological strengths and weaknesses and key management issues. A combination of our ecological and abundance approaches may be most appropriate for assessing ecological impact, whereas our socioeconomic approach is more useful for understanding social dimensions. These approaches are readily transferrable to other regions and taxa; if refined, they can help standardize the assessment of impacts of nonnative species.  相似文献   

20.
Rights & Nature     
Due to the significant and often careless human impact on the natural environment, there are serious problems facing the people of today and of future generations. To date, ethical, aesthetic, religious, and economic arguments for the conservation and protection of the natural environment have made relatively little headway. Another approach, one capable of garnering attention and motivating action, would be welcome. There is another approach, one that I will call a rights approach. Speaking generally, this approach is an attempt to address environmental issues via the language and theory of legal and moral rights. Ultimately, it is our duties to our fellow humans that explain why we have duties regarding the natural environment. There are three main contenders among theories that can be called rights approaches to environmental issues. The first identifies the (alleged) human right to a healthful environment as the source of our obligations to conserve and protect nature. The second approach has it that our duties to nature arise from the rights of the constituents of nature themselves, its flora and fauna. The third approach to addressing environmental problems via rights is, I argue, the best path to environmental conservation and protection. This approach—which grounds duties toward nature on the human right to health—has the benefits of being a straightforward, uncontroversial, and simple approach to issues and problems that desperately need to be resolved.  相似文献   

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