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911.
采用臭氧氧化—包埋菌流化床生物处理组合工艺对煤气化废水进行深度处理。实验结果表明:当臭氧的质量浓度20 mg/L、臭氧进气流量1.5 L/min、臭氧通气时间30 min、包埋菌流化床水力停留时间24 h时,臭氧氧化工序的COD去除率达到30.0%~40.0%,总酚去除率达到100.0%;包埋菌流化床工序的COD去除率达到60.0%以上,氨氮的去除率大于95.0%;经组合工艺处理后,出水COD<60 mg/L,ρ(氨氮)<1.0 mg/L,ρ(总酚)未检出,色度小于50倍,达到GB8978—1996《污水综合排放标准》中的一级排放标准。  相似文献   
912.
Life cycle assessment (LCA) is increasingly used in waste management to identify strategies that prevent or minimise negative impacts on ecosystems, human health or natural resources. However, the quality of the provided support to decision- and policy-makers is strongly dependent on a proper conduct of the LCA. How has LCA been applied until now? Are there any inconsistencies in the past practice? To answer these questions, we draw on a critical review of 222 published LCA studies of solid waste management systems. We analyse the past practice against the ISO standard requirements and the ILCD Handbook guidelines for each major step within the goal definition, scope definition, inventory analysis, impact assessment, and interpretation phases of the methodology. Results show that malpractices exist in several aspects of the LCA with large differences across studies. Examples are a frequent neglect of the goal definition, a frequent lack of transparency and precision in the definition of the scope of the study, e.g. an unclear delimitation of the system boundaries, a truncated impact coverage, difficulties in capturing influential local specificities such as representative waste compositions into the inventory, and a frequent lack of essential sensitivity and uncertainty analyses. Many of these aspects are important for the reliability of the results. For each of them, we therefore provide detailed recommendations to practitioners of waste management LCAs.  相似文献   
913.
在我国转变经济发展方式、调整经济结构的转型期,供销社再生资源行业面临重大的机遇和挑战。对传统再生资源回收企业如何抓住机遇、转变观念、突破创新,进行了深入、全面的分析。  相似文献   
914.
Current debates about food-borne risks (GMOs and BSE) have not only deepened public concern about how food is produced on farms, processed in factories, and transported, stored and traded. More importantly, these debates have exposed a crisis related to central social issues, such as the role of science, politics and business corporations in the decision-making processes for determining which risks societies should, or are prepared to, assume. In this article, I discuss how cultural and social constructivist studies of environmental and health risks and Ulrich Beck's theory of world risk society can contribute to the analysis of how to deal with these conflicts. The criticism of quantitative methods of risk analysis has resulted in a certain idealization of the lay knowledge of risks as being intuitively more correct than the scientific one. One consequence of this polarization between expert and lay knowledge—idealizing the latter—is a disappointing vagueness when looking for alternatives on how to deal practically with risks that have important consequences. A key obstacle to the implementation of some of the suggestions presented by the critical risk analysis approach is that, for example, in the current global dynamics of food-borne risks we can find heterogeneous alliances for and against GMOs allying lay people and experts, as well as conventional and unconventional social actors, in a complicated manner, at the regional, national and international levels. Since a significant part of the analysis of manufactured risks focuses on the situation of highly industrialized countries, a more complex perspective of these lay and scientific alliances can be obtained from a more extensive study of the reactions surrounding GMOs and BSE in less-industrialized countries, such as Brazil. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
915.
对普光气田油菜的二氧化硫熏气实验   总被引:1,自引:0,他引:1  
为探讨普光气田废气对周围农作物的影响和生物监测方法,选择气田周边油菜作为受试样本,对其进行二氧化硫现场熏气实验。结果表明,油菜在受到1.43 mg/m3浓度、3小时二氧化硫熏气后,植株耐受,不产生明显受害症状;叶片含硫量、MDA含量、可溶性蛋白含量等指标的测定结果与二氧化硫熏气浓度、熏气时间存在显著的相关关系。  相似文献   
916.
实验分别考察了外加乙酸钠、葡萄糖、酒石酸钾钠、甲醇等4种低分子有机碳源对生物膜填料塔烟气同时脱硫脱氮效率的影响。结果表明,外加乙酸钠的脱氮效果最佳,对NOx的平均去除率为62.05%;外加葡萄糖、酒石酸钾钠、甲醇时的NOx平均去除率分别为51.03%、46.98%、58.71%。乙酸钠、酒石酸钾钠、甲醇均能使SO2的去除率达到100%,葡萄糖显著降低了SO2的去除率。乙酸钠是在生物膜填料塔烟气同时脱硫脱氮技术中适宜的外加碳源。  相似文献   
917.
A forensic approach was used to evaluate sediments from Portão Stream, including analysis of metals, carbon (C) and nitrogen (N) stable isotopes, and C:N ratios. Samples collected at various points located along the stream were tested in order to investigate a possible illegal leachate input. The studied stream is heavily impacted by sewage and industrial discharges from two cities along its course. Among the metals analyzed, chromium (Cr) was noticeably the main pollutant, showing the highest levels, above regulatory limits, downstream from some potential sources of effluents enriched with this metal. Isotope analyses revealed a general trend of depletion in the heavier isotope along the stream for C and N. The exception was one point near a hazardous waste landfill, where relatively more enriched δ13C and δ15N values were found. The isotope and metal analysis results indicated that this site was affected by a particular source, demonstrating the combination of these parameters could be used for the discrimination of sources in a heavily polluted stream. Nevertheless, further investigations are necessary to provide a comprehensive evaluation of the biogeochemical processes involved in the incorporation of leachate in sediments to use this analysis as evidence for the illegal leachate discharge.  相似文献   
918.
好氧颗粒污泥自生动态膜生物反应器处理碱减量印染废水   总被引:1,自引:0,他引:1  
金诚  杨波  李方  田晴 《环境工程学报》2014,8(9):3819-3824
自生动态膜生物反应器(SFDMBR)接种颗粒污泥启动,研究溶解氧浓度和水力停留时间对该反应器处理碱减量印染废水的影响。自生动态膜生物反应器形成稳定的动态膜后,出水浊度小于10 NTU,系统对浊度的去除率在90%以上,溶解氧和水力停留时间对反应器出水浊度基本无影响。系统对废水色度的去除率随着溶解氧浓度的提高和水力停留时间的延长而增加,但是系统对色度的去除效率一般不超过40%。溶解氧浓度由0.3 mg/L逐渐增大至2.4 mg/L,COD的去除率由40%提升至80%,而当溶解氧浓度大于1.0 mg/L后,UV254的去除率达到95%。水力停留时间在8~48 h时,COD去除效率由65%逐渐上升至85%左右;水力停留时间在8~32 h,UV254去除效率为68%~93%,超过32 h后水力停留时间对UV254去除效率的影响已不明显。  相似文献   
919.
为了实现对茂县水资源的高效利用,将水资源开发利用评价的知识与地理信息系统结合在一起,设计出一个基于GIS的水资源开发利用评价系统,从而对茂县的水资源合理利用和加大开发提供一个有力支持,以满足对茂县经济社会发展的要求。本文对该系统的需求分析、系统结构、数据、系统各功能、系统实现进行了说明。  相似文献   
920.
区域间产业结构的同构与异构取决于在市场调节和宏观调控中生产要素的结构与流动特征,其特征量的相似性导致产业结构的同构,产业同构在一定时空条件下具有合意性。随着区域经济一体化进程的加快,其非合意性愈显突出。区域产业同构优化的本质动力在于生产要素结构及其流动特征量的变化,通过不同层级区域产业规划战略和区域间经济合作实现生产要素的合理组合与流动,以产业集群化之路实现区域产业结构的高级化,使区域产业结构朝着优化、持续方向发展。  相似文献   
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