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21.
城市中水系统组成及效益分析   总被引:2,自引:0,他引:2  
作者阐述了当前城市中水系统的组成及应用现状,并对济南市舜耕小区中水系统的处理流程、经济效益等方面进行分析探讨,提出目前制约城市中水系统发展的主要问题,并为中水回用的顺利实施提供参考。  相似文献   
22.
基于安全投入产出模型的城市安全资源优化策略   总被引:3,自引:2,他引:3  
城市安全投入与安全经济效益是制约城市安全产出的两个关键因素。为了揭示两者间的关系及其在提高城市安全度方面的作用,笔者借鉴安全经济学理论和方法,在研讨安全投入产出概论的基础上,在安全经济效益不变和安全投入量已知的情况下,提出了建立安全投入产出模型的方法。并以企业为例,从微观上验证了模型的有效性。不仅为城市安全管理决策者提供了制定安全投入目标、确定安全投入效用水平的量化工具,而且更加突出了提高安全经济效益的重要性。同时,提出了建立“资源共享”的城市重大危险源安全应急网络策略,为进一步优化城市安全资源配置和提高资源利用率奠定了基础。  相似文献   
23.
Conservation decision makers commonly use project‐scoring metrics that are inconsistent with theory on optimal ranking of projects. As a result, there may often be a loss of environmental benefits. We estimated the magnitudes of these losses for various metrics that deviate from theory in ways that are common in practice. These metrics included cases where relevant variables were omitted from the benefits metric, project costs were omitted, and benefits were calculated using a faulty functional form. We estimated distributions of parameters from 129 environmental projects from Australia, New Zealand, and Italy for which detailed analyses had been completed previously. The cost of using poor prioritization metrics (in terms of lost environmental values) was often high—up to 80% in the scenarios we examined. The cost in percentage terms was greater when the budget was smaller. The most costly errors were omitting information about environmental values (up to 31% loss of environmental values), omitting project costs (up to 35% loss), omitting the effectiveness of management actions (up to 9% loss), and using a weighted‐additive decision metric for variables that should be multiplied (up to 23% loss). The latter 3 are errors that occur commonly in real‐world decision metrics, in combination often reducing potential benefits from conservation investments by 30–50%. Uncertainty about parameter values also reduced the benefits from investments in conservation projects but often not by as much as faulty prioritization metrics.  相似文献   
24.
针对昆钢动力能源分公司制氢站建成投产后出现的环保污染和所带来的生产运行问题,对制氢系统原装置技术存在问题进行分析,提出优化改进方案,并对实施后的效果、环境效益、经济效益等进行分析。优化方案的实施彻底解决了制氢站建成后产生的环保污染问题。  相似文献   
25.
我国因燃煤导致的SO2污染危害十分严重。从清洁生产角度出发,通过比较锅炉烟气脱硫各种方法的优缺点,确定氨法脱硫作为化工企业处理锅炉烟气的工艺。介绍了氨法脱硫机理,工艺各系统结构组成,进行了经济及社会效益分析。氨法脱硫工艺可以去除93%的SO2,处理后的烟气达到了国家排放标准,脱硫副产品硫酸铵可以转交给同区域的企业,深加工为优质化肥。说明发展清洁生产和循环经济是企业预防和控制污染的有效途径,是实现可持续发展战略的必然选择,有利于企业技术进步,提高管理水平,增强综合竞争能力。  相似文献   
26.
许付仁 《环境科学与管理》2007,32(1):142-143,146
2004年台安县洪家农牧场引进加拿大优质苜蓿草进行种植实验.通过清种、林地间作和不种苜蓿草对比实验,对土壤速效氮、速效磷、速效钾、有机质、PH值、含水量进行分析,得出种植苜蓿草所产生的生态环境效益和经济效益.此项实验结论说明,紫色苜蓿是牧草之王,可促进养殖业的发展,对改善生态环境,防止土壤沙化和水土流失,改善农业结构,实现生态良性循环起到积极的促进作用,对改善生态环境起到了良好的示范作用.  相似文献   
27.
文章基于臭氧(O3)处理法处理循环冷却水因可以同时达到阻垢脱垢、缓蚀、杀菌等多重功能,其在国外已得到广泛应用,同时国内也逐步普及应用的环境下,结合国内外长期的工程实践经验,从节水、节能、减排和公共卫生效益四个方面,详细分析了臭氧处理循环冷却水所带来的巨大经济效益、社会效益和环境效益。  相似文献   
28.
The paper attempts to conceptualise a range of problems arising from project appraisals. The author presents some general considerations concerning the role of social appraisal in territorial planning, the theoretical weaknesses of cost‐benefit analysis in assessing the effects of projects on territorial resources and some questions relating to assessment methodologies and the welfare foundations of social appraisal within planning practices. The author moves away from evaluation as a technical process towards one which also incorporates ‘practical’ knowledge in a process of argumentation.  相似文献   
29.
This paper presents an integrated system for the assessmentof technical and non-technical measures that are putforward in order to reduce air pollution levels in urbanareas. In contrast to the majority of the currentlyemployed assessment tools, this system allows for theevaluation of any proposed air pollution control measure interms of its combined impact on air quality and socialwelfare, by correlating the environmental and economicaspects of alternative air pollution abatement solutions.Based on the multi-pollutant, multi-effect concept, thesystem presented aims in providing policy-makers with areliable tool for the objective assessment of the mostcost-effective packages of measures, the latter beingallocated according to the particular features and needs ofthe areas examined.  相似文献   
30.
ABSTRACT: Bringing water from Colorado River via the Central Arizona Project was perceived as the sole solution for Tucson Basin's water problem. Soon after Central Arizona Project's water arrived in Tucson in 1992, its quality provoked a quarrel over its use for potable purposes. A significant outcome of that quarrel was the enactment of the 1995 Proposition 200. The Proposition 200 precludes the use of Central Arizona Project's water for potable purposes, unless it is treated. Yet, it encourages using it for non‐potable purposes and for replenishing the Tucson aquifer through recharge. This paper examines the economic issues involved in utilizing Central Arizona Project's water for recharge. Four planning scenarios were designed to measure and compare the costs and benefits with and without Central Arizona Project's water recharge. Cost‐benefit analysis was utilized to measure recharge costs and benefits and to derive a rough estimate of cost savings from preventing land subsidence. The results indicate that the institutional requirements can be met with Central Arizona Project's water recharge. The economic benefits from reducing pumping cost and saving groundwater are not economically significant. Yet, when combining the use of Central Arizona Project's water for recharge and non‐potable purposes, it demonstrates positive net economic benefits.  相似文献   
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