首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
ABSTRACT: A dynamic programming model is presented for planning the optimal capacity expansion sequence of waste water treatment plants servicing sewerage systems with infiltration/inflow. The model employs a nonlinear deterministic demand function for waste water treatment plant capacity. Model output provides the optimal timing, size, and sequence for treatment plant capacity expansion projects and infiltration/inflow removal projects. An example problem is presented and solved.  相似文献   

2.
Water reuse is an emerging and promising non-conventional water resource. Feasibility studies are essential tools in the decision making process for the implementation of water-reuse projects. However, the methods used to assess economic feasibility tend to focus on internal costs, while external impacts are relegated to unsubstantiated statements about the advantages of water reuse. Using the concept of shadow prices for undesirable outputs of water reclamation, the current study developed a theoretical methodology to assess internal and external economic impacts. The proposed methodological approach is applied to 13 wastewater treatment plants in the Valencia region of Spain that reuse effluent for environmental purposes. Internal benefit analyses indicated that only a proportion of projects were economically viable, while when external benefits are incorporated all projects were economically viable. In conclusion, the economic feasibility assessments of water-reuse projects should quantitatively evaluate economic, environmental and resource availability.  相似文献   

3.
ABSTRACT. There have been many changes in the waste water treatment requirements at St. Louis District Corps of Engineers projects over the past few years. Discussed are the methods considered for treating these wastes. Extended aeration plant, followed by filtration, is the process used in most of the areas. The treatment plant operators have become key members of the project operation team. A discussion of the Districts operator training program is presented along with the operator's job requirements. Through a Spring inspection of all treatment plants in the District, a mechanism has been provided for encouraging feedback to the design engineer from the operator.  相似文献   

4.
从潜流式人工湿地设计谈提高氮去除率方法的途径   总被引:2,自引:0,他引:2  
从相关文献与实际工程来看,潜流式人工湿地对含氮污染物的去除效果与含碳污染物的去除比相对较弱。参考国内外大量文献资料,根据潜流式人工湿地的常规工艺和脱氮机理,本文总结并提出了一些提高污水氮去除率的方法。指出应根据具体的情况选择合适的植物和基质、通过工程措施和工艺组合、优化工艺设计及其他一些方法来创造脱氮所需环境,从而达到提高潜流式人工湿地氮去除率的目的。  相似文献   

5.
我国城市生活垃圾处理行业2010年发展综述   总被引:10,自引:0,他引:10  
简述了2010年我国城市生活垃圾处理的总体状况;归纳了2010年国家发布和实施的有关标准和政策;介绍了2010年新批准申请CDM的填埋气体利用项目和垃圾焚烧发电项目、垃圾堆肥项目,以及新投入运行的生活垃圾焚烧发电厂;对城市生活垃圾处理行业的发展进行了展望。  相似文献   

6.
我国城市生活垃圾处理行业2009年发展综述   总被引:3,自引:0,他引:3  
简述了2009年我国城市生活垃圾处理的总体状况;归纳了2009年国家发布和实施的有关标准和政策;介绍了2009年新批准申请CDM的填埋气体利用项目和垃圾焚烧发电项目、垃圾堆肥项目,以及新投入运行的生活垃圾焚烧发电厂;对城市生活垃圾处理行业的发展进行了展望。  相似文献   

7.
ABSTRACT Mathematical models are formulated for selection of water resources projects to meet the future additional water requirements of a given region at the minimum present worth cost. The projects available are surface water reservoirs and desalination plants. The modles are used for selecting both the development sequence of projects and their optimum sizes. Decisions with regard to planning time horizon and discount rates are made outside of the mathematical model. The algorithm used for solving these models is an integer programming routine using the implicit enumeration technique. Some computational results are presented for a hypothetical case.  相似文献   

8.
Office building retrofit is a sector being highlighted in Australia because of the mature office building market characterised by a large proportion of ageing properties. The increasing number of office building retrofit projects strengthens the need for waste management. Retrofit projects possess unique characteristics in comparison to traditional demolition and new builds such as partial operation of buildings, constrained site spaces and limited access to as-build information. Waste management activities in retrofit projects can be influenced by issues that are different from traditional construction and demolition projects. However, previous research on building retrofit projects has not provided an understanding of the critical issues affecting waste management.This research identifies the critical factors which influence the management of waste in office building retrofit projects through a literature study and a questionnaire survey to industry practitioners. Statistical analysis on a range of potential waste issues reveals the critical factors, as agreed upon by survey respondents in consideration of their different professional responsibilities and work natures. The factors are grouped into five dimensions, comprising industry culture, organisational support and incentive, existing building information, design, and project delivery process. The discussions of the dimensions indicate that the waste management factors of office building retrofit projects are further intensified compared to those for general demolition and construction because retrofit projects involve existing buildings which are partially operating with constrained work space and limited building information. Recommendations for improving waste management in office building retrofit projects are generalised such as waste planning, auditing and assessment in the planning and designing stage, collaboration and coordination of various stakeholders and different specialists, optimised building surveying and BIM technologies for waste analysis, and new design strategies for waste prevention.  相似文献   

9.
ABSTRACT. Two factors affecting the centralization of wastewater treatment facilities were investigated; the cost of collection and treatment systems and the performance of treatment plants. Based on computer-generated minimum cost designs, wastewater collection networks were found to be characterized by diseconomies of scale of magnitude similar to the reported economies of scale for wastewater treatment works. The combined costs of collection and treatment are U-shaped functions from which the least cost size of collection and treatment systems were found for particular values of population density. Examination of the day-to-day performance of five metropoitan-area waste-water treatment plants revealed that, for time series shorter than one month, the day-to-day variation in effluent quality was random, although the variation in quantity discharged was distinctly non-random. The performances of all five plants on any given day showed little correlation. This suggests that the decentralization of treatment facilities can produce benefits both through the reduction in quantities of waste discharged at a given point and through in-stream averaging of the varying performances of several treatment plants. Since the cost function of collection and treatment combined is generally flat in the region of the minimum-cost size, little penalty is invoked to gain the potential benefits of treatment plant decentralization.  相似文献   

10.
Sustainable harvest of natural products that meets the needs of local people has been viewed by many as an important means for sustaining conservation projects. Although plants often respond to tissue damage through compensatory growth, it may not secure long-term sustainability of the populations because many plants enhance individual well-being at the expense of propagation. Sustainability may further be threatened by infrequent, large-scale events, especially ill-documented ones. We studied the impacts of sprout harvesting on sprout growth in a dwarf bamboo (Pseudosasa usawai) population that has seemingly recovered from an infrequent, large-scale masting event. Experimental results suggest that although a single sprout harvest did not significantly alter the subsequent abundance and structure of sprouts, culm damage that accompanied sprout harvesting resulted in shorter, thinner, and fewer sprouts. Weaker recovery was found in windward, continually harvested, and more severely damaged sites. These findings suggest that sprout growth of damaged dwarf bamboos is likely non-compensatory, but is instead supported through physiological integration whose strength is determined by the well-being of the supplying ramets. Healthy culms closer to the damage also provided more resources than those farther away. Sustainable harvesting of sprouts could benefit from organized community efforts to limit the magnitude of culm damage, provide adequate spacing between harvested sites, and ensure sufficient time interval between harvests. Vegetation boundaries relatively resilient to infrequent, large-scale events are likely maintained by climatic factors and may be sensitive to climate change. Continual monitoring is, therefore, integral to the sustainability of harvesting projects.  相似文献   

11.
随着居民环境和公众维权意识的提高,邻避冲突会逐步从感性的情绪表达过渡到理性的利益诉求。选择房地产作为度量邻避设施导致的资产损失的媒介,基于双重差分模型构建了邻避设施导致的资产损失评估方法。以南京市为例,选择55个有效住宅社区1980个样本作为处理组,选择25个商圈住宅社区900个样本作为对照组,研究了化工厂、污水处理厂、公墓和监狱四种典型邻避设施对周边资产价格的影响。研究发现:不同邻避设施对周边资产影响不同;化工厂、监狱、公墓和污水处理厂的影响程度依次为302、284、194和180;区域繁华因素等可以消除邻避设施的部分影响;邻避设施周边资产的市场表现仅满足"上涨时涨得少",而不满足"下跌时跌得多"的特点。  相似文献   

12.
C.A. Adams  S. Bell 《Local Environment》2015,20(12):1473-1488
Micro- and small-scale low-carbon energy generators embedded within villages, towns and cities can provide a valuable income stream for local communities among other potential benefits. There are a range of social, political, technical and environmental factors that may impact upon the success of a planned energy generation project; however, these factors are rarely considered in unison. The aim of this research is to investigate and understand the concerns relating to equity and distributional justice that impact upon local groups interested in developing energy projects and to determine whether a whole systems approach can be used to draw out perceived issues. This has been achieved by working with two small village groups to test a newly developed energy equity assessment tool. This paper reports research findings from two villages in the UK both planning energy projects that intended to benefit their respective villages and examines perceived issues relating to equity and distributional justice associated with the proposed schemes. The research highlights some challenges facing community groups when planning micro- and small-scale energy projects and demonstrates the commitment, tenacity and high levels of personal risk that these groups have to bear in order to bring their projects to fruition and comments as to the type of actions that may be required to more wholly consider equity issues while developing future energy policy.  相似文献   

13.
电网项目属于非污染型生态项目,具有该类型项目特有的影响因子单一、项目涉及范围广及环境敏感点分布不均等特点。该类项目竣工环保验收中存在6种主要问题,针对验收率、验收监测、公众参与等方面,通过制定规范、加强管理、落实环保治理措施等层面,给出了相对的解决方案。通过方案的实施,主要常见问题可得到解决或改善。  相似文献   

14.
In evaluating the costs and benefits of water resources development projects, the World Bank examines the economic, social and environmental aspects of the project. Some of these aspects are more easily quantified than others. The paper reviews some aspects that have been quantified by the Bank and describes others which have not. By way of illustrating the difficulty of quantification, the Bank's efforts to quantify the health hazards resulting from the introduction of irrigation projects is examined. In addition, the Bank's requirements with respect to social and environmental factors as they affect water resources projects are described.  相似文献   

15.
The planning of facilities to improve the environment is often carried through in the form of locally based construction projects. These projects can be complex, involving a variety of issues and a number of different actors from both the public and private sectors. By drawing on previous research on project planning, an analytical model for analysing the issues connected with the planning and implementation of environmental projects is developed. The main argument of the paper is the importance of considering how context-specific factors affect project design and project management. The empirical material is taken from the planning of two biogas projects in Sweden and it is showed how differences in factors such as the actors involved, the organisational framework and the political setting lead to two markedly distinct planning approaches. The results of the paper, which also highlight the importance of a flexible planning approach, are relevant not only for biogas but also for other projects with similar characteristics.  相似文献   

16.
以上海和苏南地区农村生活污水治理的10个示范工程为例,评估研究了农村生活污水治理技术方案的合理性。文章认为,在技术合理性方面,现有示范工程的处理模式选择和工艺设计基本实现了因地制宜,但在成本的有效性方面,现有示范工程还存在较大的成本下降空间。  相似文献   

17.
3 /day (800,000 US gallons) of municipal wastewater and beef processing wastewater. A large nongovernmental organization hastened restoration with a development process that outlined restoration goals and management objectives to satisfy a dual mandate of wastewater treatment and wildlife habitat creation. In 1995, after five years of wastewater additions, the basins had been refilled and the surrounding uplands had been acquired and restored. The Frank Lake Conservation Area currently provides high-quality habitat for a variety of wildlife in a region where many of the native plants and animals species have been lost due to habitat loss and fragmentation. The success of upland and water management strategies is reflected in the increase of target species' abundance and richness: 50 shorebird species, 44 waterfowl species, 15 raptor species, and 28 other new bird species have returned to the marsh since restoration. As well, significant N and P reduction occurs as waters flow through the first basin of the marsh. The management strategies of this project that satisfied a dual mandate serve as a model to guide managers of other large-scale wetland restoration projects.  相似文献   

18.
低山丘陵区风力发电场项目建设对生态的破坏日益明显,开展风电场施工期环境监理具有重要意义。通过对低山丘陵区风电项目施工期环境监理经验的总结,阐述了铁岭市风电场生态恢复的现状及开展生态恢复环境监理的重要作用,并对施工期的合理安排、原生植被的保护与利用、监理关键技术及环境监理人员的素质要求等相关生态恢复环境监理问题进行了探讨。  相似文献   

19.
This paper is about improving the viability of discard-reduction pilot projects. One way to address the problem of wasteful discarding of fish at sea is to initiate pilot projects to trial potential solutions, such as selective gear, area closures, discard bans and data enhancement, which could subsequently be adopted by the fishing industry, either voluntarily or through regulation. However, such pilot projects are often difficult both to set up and to sustain through to completion and implementation. This study reviewed 15 discard-related pilot projects to find out what were the most important determinants of their success or lack of it, and to recommend ways in which the prospects of future pilots could be improved. The review identifies the seven most important factors associated with the viability of the pilot projects - fisheries crises; incentivization; funding; expertise; leadership; and enforcement - and shows how fisheries regulators could take steps to reinforce these factors – by faster responses to crises; more incentives and funding; greater use of fishers' knowledge and leadership; and better enforcement mechanisms.  相似文献   

20.
人工湿地是近年来国内外应用较多、发展较快的一种污水处理技术,本文从国内外人工湿地净化河水的技术应用出发,列举了人工湿地处理河水污染的效果和优势,并对湿地净化河水效率影响较大的湿地植物、填料、气候条件以及湿地构造4个因素进行了比较、分析和总结,最后对人工湿地净化河道水质进行了展望。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号