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721.
北京市开展区域水环境合作探究   总被引:1,自引:0,他引:1  
通过分析北京市地表水资源、水环境质量现状及存在的问题,得出生态环境用水严重短缺是制约北京市水环境质量全面改善的根本原因,并对此提出全面加强区域水环境合作、改善北京市水环境的基本思路,及与周边地区开展水环境合作的途径及建议。  相似文献   
722.
针对城市化进程加快引发的一系列环境污染问题,指出了加快污染防治设施社会化运营的必要性,并从污染治理设施的种类、污染治理设施的社会化运营分析和运作模式三方面论述了如何进行污染治理设施的社会化运营,从经济发展、污染防治设施运行、引入竞争机制等方面概述了污染防治设施社会化运营对区域环境与经济协调发展的影响。  相似文献   
723.
基于生命周期理论,采用CNI环境影响评价方法对我国水泥生产的环境负荷进行了定量分析。结果表明:水泥生产的环境影响主要体现在温室效应、不可再生能源消耗和不可再生资源消耗,其环境负荷分别占对应环境影响类型世界总负荷的2.76%,2.34%和1.39%,2006年我国水泥生产的环境负荷约占世界总负荷的1.28%,其中,立窑生产工艺、湿法回转窑生产工艺和新型干法生产工艺的环境负荷分别为0.84%,0.12%和0.32%。通过行业结构调整,用新型干法生产工艺取代其他落后的生产工艺,可使我国水泥生产的环境负荷降至世界总负荷的1%左右。  相似文献   
724.
塔里木河地处我国西北干旱区,是我国最长的内陆河。过去50a来由于大规模的不合理的水土资源开发和人类活动,导致塔里木河在以水资源开发利用为核心的大强度人类经济、社会活动的作用下,流域自然生态过程发生了显著变化。分析了塔里木河下游地下水位下降对绿洲农业生态环境的影响,提出了保障该地区生态和经济发展的对策与建议。  相似文献   
725.
论焦化行业环境风险防范措施及应急预案   总被引:2,自引:0,他引:2  
本文对焦化行业的原辅材料及产品的理化性质、生产过程中潜在的环境风险进行了识别,并在此基础上有针对性的提出了焦化行业环境风险防范措施及应急预案。  相似文献   
726.
Post combustion carbon dioxide (CO2) capture is one of the most commonly adopted technologies for reducing industrial CO2 emissions, which is now an important goal given the widespread concern over global warming. Research on amine-based CO2 capture has mainly focused on improving effectiveness and efficiency of the CO2 capture process. Our research work focuses on studying the relationships among the significant parameters influencing CO2 production because an enhanced understanding of the intricate relationships among the parameters involved in the process is critical for improving efficiency of the CO2 capture process. This paper presents a statistical study that explores the relationships among parameters involved in the amine-based post combustion CO2 capture process at the International Centre for CO2 Capture (ITC) located in Regina, Saskatchewan of Canada. A multiple regression technique has been applied for analysis of data collected at the CO2 capture pilot plant at ITC. The parameters have been carefully selected to avoid issues of multicollinearity, and four mathematical models among the key parameters identified have been developed. The models have been tested, and accuracy of the models is found to be satisfactory. The models developed in this study describe part of the CO2 capture process and can help to predict performance of the CO2 capture process at ITC under different conditions. Some results from a preliminary validation process will also be presented.  相似文献   
727.
The goal of this paper is to find methodologies for removing a selection of impurities (H2O, O2, Ar, N2, SOx and NOx) from CO2 present in the flue gas of two oxy-combustion power plants fired with either natural gas (467 MW) or pulverized fuel (596 MW). The resulting purified stream, containing mainly CO2, is assumed to be stored in an aquifer or utilized for enhanced oil recovery (EOR) purposes. Focus has been given to power cycle efficiency i.e.: work and heat requirements for the purification process, CO2 purity and recovery factor (kg of CO2 that is sent to storage per kg of CO2 in the flue gas). Two different methodologies (here called Case I and Case II) for flue gas purification have been developed, both based on phase separation using simple flash units (Case I) or a distillation column (Case II). In both cases purified flue gas is liquefied and its pressure brought to 110 atm prior to storage.Case I: A simple flue gas separation takes place by means of two flash units integrated in the CO2 compression process. Heat in the process is removed by evaporating the purified liquid CO2 streams coming out from both flashes. Case I shows a good performance when dealing with flue gases with low concentration of impurities. CO2 fraction after purification is over 96% with a CO2 recovery factor of 96.2% for the NG-fired flue gas and 88.1% for the PF-fired flue gas. Impurities removal together with flue gas compression and liquefaction reduces power plant output of 4.8% for the NG-fired flue gas and 11.6% for the PF-fired flue gas. The total amount of work requirement per kg stored CO2 is 453 kJ for the NG-fired flue gas and 586 kJ for the PF-fired flue gas.Case II: Impurities are removed from the flue gas in a distillation column. Two refrigeration loops (ethane and propane) have been used in order to partially liquefy the flue gas and for heat removal from a partial condenser. Case II can remove higher amounts of impurities than Case I. CO2 purity prior to storage is over 99%; CO2 recovery factor is somewhat lower than in Case I: 95.4% for the NG-fired flue gas and 86.9% for the PF-fired flue gas, reduction in the power plant output is similar to Case I.Due to the lower CO2 recovery factor the total amount of work per kg stored CO2 is somewhat higher for Case II: 457 kJ for the NG-fired flue gas and 603 kJ for the PF-fired flue gas.  相似文献   
728.
A numerical study was conducted to predict pCO2 change in the ocean on a continental shelf by the leakage of CO2, which is originally stored in the aquifer under the seabed, in the case that a large fault connects the CO2 reservoir and the seabed by an earthquake or other diastrophism. The leakage rate was set to be 6.025 × 10−4 kg/m2/sec from 2 m × 100 m fault band, which corresponds to 3800 t-CO2/year, referring to the monitored seepage rate from an existing EOR field. The target space in this study was limited to the ocean above the seabed, the depth of which was 200 or 500 m. The computational domain was idealistically rectangular with the seabed fault-band perpendicular to the uniform flow. The CO2 takes a form of bubbles or droplets, depending on the depth of water, and their behaviour and dissolution were numerically simulated during their rise in seawater flow. The advection–diffusion of dissolved CO2 was also simulated. As a result, it was suggested that the leaked CO2 droplets/bubbles all dissolve in the seawater before spouting up to the atmosphere, and that the increase in pCO2 in the seawater was smaller than 500 μ atm.  相似文献   
729.
以位于自然保护区边缘的火电厂建设项目环境影响评价为实例,阐述了火电厂生态环境评价中对自然保护区珍稀鸟类的保护方法,以供类似项目的生态环境影响评价借鉴。  相似文献   
730.
Obtaining knowledge about factors affecting health, safety and environment (HSE) is of major interest to the petroleum industry, but there is currently a severe shortage of relevant studies. The aim of this study was to examine the relative influence of offshore installation (local working environment) and company belonging on employees’ opinions concerning occupational health and safety. We analyzed data from a safety climate survey answered by 4479 Norwegian offshore petroleum employees in 2005 on the dimensions “Safety prioritisation”, “Safety management and involvement”, “Safety versus production”, “Individual motivation”, “System comprehension” and “Competence” using one way analysis of variance (ANOVA), effect size and mixed model. The companies differed significantly for “Safety prioritisation”, “Safety versus production”, “Individual motivation”, “System comprehension” and “Competence”. The local offshore installation explained more of the safety climate than the company they were employed in or worked for did.  相似文献   
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