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551.
PDW-Ⅱ型石油钻井污水处理机的研制与应用 总被引:3,自引:1,他引:2
本文介绍了PDW-Ⅱ型石油钻井污水处理机的开发研究及现场试验结果。该机采用一步絮凝沉淀的工艺过程,适用于低色度、低浊度石油钻井污水的处理。试验表明:处理后出水达到国家综合污水二级排放标准,可以排放或回用于井场。 相似文献
552.
核电与核废物管理 总被引:1,自引:0,他引:1
周宏春 《中国人口.资源与环境》1994,4(4):23-28
核能是一种能量密度大、稳定性好、燃料运输量小、综合经济效益好的能源。世界各国核电在总发电量中的比例逐年上升,1992年达17%,而我国仅占0.1%。在目前我国电力短缺的条件下,发展核电、提高核电在总电量中的比例,不失为我国发展能源工业的一个战略目标。在发展核电过程中,要重视核废物的处理和处置,以保证人类健康和环境免遭放射性的污染。 相似文献
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构建了多组上流式生物电化学反应系统(up-flow bio-electrochemical system,简称UBES),研究了UBES降解2-氯硝基苯(2-CNB)废水的特性,探究了2-CNB在UBES中降解的影响因素和降解途径.实验结果表明:在一定范围内增大外加电压,2-CNB在UBES系统中降解速率与电压值呈正相关,当外加电压超过某一范围时,2-CNB降解速率下降.中性条件下,当2-CNB初始浓度为20 mg·L~(-1),外加电压为1.4 V反应30 h后,2-CNB的降解率达到99.61%;采用HPLC、HPLC/MS、HPLC/MS/MS及IC技术,分析了2-CNB降解24 h的中间产物,结果表明:2-CNB在降解过程中将产生苯胺、2-氯苯酚、苯二酚、2-氯苯胺、2-氯亚硝基苯、2-氯羟基苯胺、正己酸、丁二酸等中间产物,部分Cl元素和N元素分别转化为Cl~-和NO~-_3.2-CNB在UBES系统中降解包含阴极还原、阳极氧化两种降解途径. 相似文献
556.
Surface-active organic molecules (surfactants) may influence the ability of an aerosol particle to act as a cloud condensation nuclei by reducing its surface tension. One source of organic mass in aerosol particles, which may also contain surfactants, is bubble bursting on the sea surface. In order to directly compare these molecules in the ocean and aerosol particles, we developed a method using multiple solid phase extractions and high resolution mass spectrometry to characterize surface active organic molecules in both. This method has extraction efficiencies greater than 85%, 75%, and 60% for anionic, cationic, and nonionic surfactant standards, respectively. In this study, we demonstrate the presence of three ionic classes of surface active organics in atmospheric aerosol particles and estuarine water from Skidaway Island, GA. With this extraction method, organic molecules from both estuarine water and atmospheric aerosol particles significantly reduced surface tension of pure water (surface tension depression of ~ 18 mN/m) and had high ratios of hydrogen to carbon (H/C) and low ratios of oxygen to carbon (O/C), indicative of surfactants. While previous work has observed a larger fraction of anionic surface active organics in seawater and marine aerosol particles, here we show cationic surface active organics may make up a large fraction of the total surface active molecules in estuarine water (43%–47%). 相似文献
557.
赵志远 《中国环境管理干部学院学报》2014,(6):38-41
实现“村容整洁”是新农村建设的一个重要环节。当前新农村建设中废弃物主要以水池、河流、马路等为处理载体,采用直接填埋和燃烧等处理方式,这些方式处理废弃物存在较多危害。农村居民狭隘意识主导、领导工作理念欠缺、新型人才缺失、配套资金和基础设施不到位是问题产生的主要原因。可以通过转变工作理念、建立协同参与治理机制、规范的制度化激励机制、新型人才培养和引入机制、多渠道发展机制、实现资源优势整合机制来解决问题。 相似文献
558.
The human population is rising and the availability of terrestrial land and its resources are finite and, perhaps, not sufficient to deliver enough food, energy, materials and space. Thus, it is important to (further) explore and exploit the marine environment which covers no less than 71% of the earth's surface. The marine environment is very complex but can roughty be divided into two systems: natural (e.g. wild fishing) and human-made (e.g. artificial islands). In this study, characterization factors (CF) for natural and human-made marine systems were calculated in order to be able to assess the environmental impact of occupying marine surfaces, which was not possible so far in life cycle assessment. When accounting for natural resources while occupying one of these systems, it is important to consider the primary resources that are actually deprived from nature, which differs between the natural and human-made marine systems.In natural systems, the extracted biomass was accounted for through its exergy content, which is the maximum quantity of work that the system can execute in its environment. Reference flows for marine fish, seaweeds, crustaceans and mollusks were proposed and their correlated CF was calculated. For human-made systems, the deprived land resource is, in fact, the occupied area of the marine surface. Based on potential marine net primary production data (NPP), exergy based spatial and temporal CFs for ocean areal occupation were calculated. This approach was included in the Cumulative Exergy Extraction from the Natural Environment (CEENE) method which makes it the first life cycle impact assessment (LCIA) method capable of analyzing the environmental impact (and more specific the resource footprint) of marine areal occupation. Furthermore, the methodology was applied to two case studies: comparing resource consumption of on- and offshore oil production, and fish and soybean meal production for fish feed applications. 相似文献
559.
苏州市生活垃圾处理碳足迹核查 总被引:2,自引:1,他引:1
根据《PAS2050规范》的指导,结合生命周期评价技术方法和LandGEM模型,对苏州市生活垃圾填埋和焚烧处理的生命周期过程进行了碳足迹核查. 详细列出了垃圾处理过程中可能的温室气体排放源,计算各排放源的电耗或能耗,并通过与温室气体排放系数相乘最终转化为苏州市生活垃圾处理温室气体排放量. 结果表明:苏州市填埋处理1 t生活垃圾整个生命周期过程中温室气体的排放量(以CO2当量计)为1 942.47 kg,焚烧处理为-180.87 kg. 按照目前苏州市生活垃圾处理权重进行分配,可得苏州市处理1 t生活垃圾整个生命周期过程中温室气体的排放量(以CO2当量计)为880.80 kg. 在整个核查过程中,考虑了在填埋和焚烧处理时发电对温室气体带来的减量效应. 相似文献
560.
Inverse parameter estimation of individual-based models (IBMs) is a research area which is still in its infancy, in a context where conventional statistical methods are not well suited to confront this type of models with data. In this paper, we propose an original evolutionary algorithm which is designed for the calibration of complex IBMs, i.e. characterized by high stochasticity, parameter uncertainty and numerous non-linear interactions between parameters and model output. Our algorithm corresponds to a variant of the population-based incremental learning (PBIL) genetic algorithm, with a specific “optimal individual” operator. The method is presented in detail and applied to the individual-based model OSMOSE. The performance of the algorithm is evaluated and estimated parameters are compared with an independent manual calibration. The results show that automated and convergent methods for inverse parameter estimation are a significant improvement to existing ad hoc methods for the calibration of IBMs. 相似文献