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931.
在构建重庆市工业耗能相关碳排放影响因素分解模型的基础上,采用因素分解方法分析了过去十余年间(19992011)4种驱动因素对重庆市工业碳排放变化的影响,并识别出关键驱动因素。结果显示:能耗增长的主要原因是工业经济发展;工业能源强度是促进重庆市工业耗能相关碳减排的主要影响因素;产业结构因素对重庆市工业耗能相关碳排放变化的影响存在波动,但其累积效果表现为减排;能源结构因素对重庆市工业耗能相关碳排放变化没有显著影响。最后,结合各关键因素的未来发展趋势,提出重庆市工业未来低碳发展的可行途径为技术进步和产业升级。  相似文献   
932.
为探索低浓度生化尾水生物深度处理的快速挂膜方法,采用4种方法(投加壳聚糖法、投加铁离子法、接种排泥法和自然挂膜法)进行挂膜,考察其对生物膜主要特性(生物膜量MLSS、胞外聚合物(EPS))和废水处理效果的影响.结果表明:在挂膜期间,投加壳聚糖法有利于生物膜量、EPS迅速增加,两者平均含量达到4种方法中的最大值,分别为(9.26 ±3.30) mg/cm3和(42.51 ±33.49) mg/(gSS),但其生物膜活性f值最低,污染物的去除效果不是最佳;投加铁离子成膜时,生物膜特性稳定,活性高,污染物去除效果最佳,CODCr、NH4+-N、TP去除率分别较快稳定在(66.13 ±2.30)%、(92.03 ±7.72)%和(62.75 ±4.41)%;接种排泥法的生物膜量、EPS均含量、污染物去除效果比投加壳聚糖、铁离子法稍低;自然挂膜法前期对污染物去除率低,稳定时间较长,除TP外,CODCr、NH4+-N去除率在挂膜后期与投加壳聚糖法、接种排泥法相差不大.综合地看,投加铁离子法,虽然生物膜量、EPS含量略低于投加壳聚糖法,但生物膜活性高、污染去除效果好,是低浓度尾水挂膜的最佳方法.  相似文献   
933.
本文研究了混凝—催化臭氧化对垃圾渗滤液MBR出水COD、UV254和色度的去除效果及可生化性能的影响。在pH 11,FeCl3用量800 mg/L的优化条件下,COD、UV254和色度去除率分别为37.8%、61.9%和88.7%。混凝出水催化臭氧化结果表明,3%-Ce/AC催化臭氧化效率最好,COD去除率为33.6%,臭氧消耗系数为1.40 mgO3/mgCOD。经混凝—催化臭氧化处理后,MBR出水的COD、UV254及色度总去除率分别为58.7%、90.8%及98.7%,BOD5/COD从0.036提高到0.375,可生化性明显改善。  相似文献   
934.
Devising effective strategies to facilitate waste reuse depends on the solid understanding of reuse behaviors. However, previous studies of reuse behavior have been limited in scope, focusing mostly on household recycling behaviors or very limited types of industrial wastes. To gain a better understanding of the business reuse behaviors, this study examined the impact of various factors in technical, economic, regulatory, and behavioral categories in the case of coal ash generated in the United States. The results of fixed effect models for fly ash and bottom ash particularly showed the significance role of the behavioral factor. In both models, a proxy variable, which represents knowledge sharing among the power plants or the utility's decision-making, turned out to be statistically significant and had the largest coefficient estimates among a group of variables. This finding may imply that the characteristics of waste reuse behavior are determined more by business decision-making behaviors than by market or institutional factors. However, the role of the behavioral variable was stronger in the bottom ash models than in the fly ash models. While the reuse of bottom ash was determined primarily by the behavioral variable, fly ash reuse was determined by more diverse factors including economic and regulatory variables. This could be explained by material characteristics in relation to competing resources and the nature of reuse applications.  相似文献   
935.
This study tested the hypotheses that (1) exposure to treated Water Reclamation Plant (WRP) effluent will induce biological effects in exposed fish that are consistent with environmental estrogen (EE) exposure; and (2) seasonal differences in effluent composition will moderate biological effects. We conducted seven on‐site exposures using a mobile laboratory. Total estrogenicity of effluents was 10‐ to 20‐fold higher during spring than in fall. Common EEs including steroid estrogens, alkylphenols, and bisphenol‐A were ubiquitous. An unusual spike in total estrogenicity identified a combined sewer overflow event. Fathead minnows (Pimephales promelas) responded to exposure with subtle changes in vitellogenin concentrations and secondary sex characteristics. An opportunity to assess a common carp (Cyprinus carpio) population permanently sustained inside the Stickney WRP revealed pronounced exposure effects, but also the resilience of biological organisms even under long‐term exposure. In contrast to other studies, no histopathological changes were found. The mobile exposure laboratory proved capable of maintaining U.S. Environmental Protection Agency‐recommended exposure conditions while providing flexibility for rapid deployment at multiple sites with minimal operational disruption. Further studies using this platform hold promise to resolve the convoluted interactions between complex effluents and inherent biological complexity.  相似文献   
936.
The present study is targeted on the feasibility of photocatalytic treatment of industrial wastewater containing metal ions. Photoreductive deposition of metal ions using solar energy irradiated TiO2, has been investigated in presence of citric acid as a hole scavenger. Treatment studies have also been performed at pH values 2, 4, 7, 8, and 10 to determine optimum reaction conditions. Results showed that at the pH value of 2, 100% reduction was achieved for Cr(VI) in a minimum time period. A maximum removal of 95.5% was achieved for Ni(II) at the pH value of 10.  相似文献   
937.
In 2006, the British Standards Institute (BSI) published BS 8887-1 ‘Design for Manufacture, Assembly, Disassembly and End-of-life processing’ (MADE) subtitled ‘General Concepts, Processes and Requirements’. This was the first British Standard to address design for efficient post-consumer product reprocessing. By designing and planning for remanufacture, much of the embodied energy and production investment can be retrieved after the consumer no longer requires the original item. Therefore, end-of-life products become an asset rather than a liability. Design for disassembly facilitates efficient deconstruction and thus enables materials to be recycled with minimal loss of purity, thus maximising their value. The analysis presented here is based on the Standard Industrial Classification codes of companies and organisations that have purchased BS 8887-1. These data are considered in relation to the influence of environmental legislation. Company age, size and location, as well as ISO 9001 and ISO 14001 certifications, are discussed. This paper concludes by suggesting suitable directions for the continued distribution and development of this environmentally, economically and socially beneficial standard.  相似文献   
938.
通过分析厌氧处理系统VFA碱度和H2 CO3 碱度的变化特点 ,指出厌氧处理系统所需VFA碱度与运行方式、运行控制、水质、温度等因素有关 ,良好运行的厌氧系统所需碱度主要是H2 CO3 碱度 ;高效吹脱的厌氧系统所需H2 CO3 碱度很小 ,尤其是低浓度废水可通过选择投加碱度的种类以吸收CO2 或通过CO2 气相控制等手段将H2 CO3 碱度降至最小。  相似文献   
939.
The electronics industry is generally recognized as a leader in clean production practices. Industrial ecology, however, encourages a systemic approach to sectoral behavior, which means that not just production, but also the role of electronics products and services in supporting an information culture should be considered as part of a comprehensive analysis. The eventual goal should be the production of social practices and systems that provide the desired functionality and quality of life in an environmentally acceptable manner. A conceptual framework for such an analysis of information infrastructure is presented, although the analyses and data required for a full understanding remain limited and preliminary in many ways.  相似文献   
940.
关于工业园区建设中环境保护问题的若干思考   总被引:1,自引:0,他引:1  
李文明 《重庆环境科学》2003,25(8):28-30,36
为促进块状经济集聚升级,应对加入WTO以后的压力,弥补个私企业规模缺陷等经济发展进程中的问题,需要加快特色工业园区建设。如何使特色块状经济与环境保护良性互动,实现经济效益、社会效益、环境效益的三统一,促进社会经济的可持续发展。本文结合诸暨经济、环境现状,提出了在加快特色工业园区建设的同时,要重视解决环境问题。为此,提出在工业园区建设中,要编制环保规划、进行环境影响评价、严格执行“三同时”制度、推行清洁生产和ISO14000体系认证、实行污染集中治理和专业化治理污染等方面的对策及建议。  相似文献   
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