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991.
我国区域性复合型大气污染日益严重,以燃煤火电为代表的煤炭消费相关产业已经成为最为重要的大气污染源,并已成为制约燃煤火电行业发展的重要因素. 应用RAMS(区域大气模式系统)-CMAQ(多尺度空气质量模式系统)模拟和评估全国燃煤火电对区域大气环境的影响,并分析了近地面风场对燃煤火电布局的影响;基于煤炭消费总量增长趋势与控制目标,预测燃煤火电的发展规模,提出全国燃煤火电分区布局策略. 结果表明:燃煤电厂对我国东部地区NOx、SO2、PM2.5以及PM10排放通量的贡献较大,但燃煤电厂对ρ(SO2)、ρ(O3)、ρ(PM2.5)和ρ(PM10)年均值的贡献率较小,基本维持在10%以下,仅对ρ(NOx)年均值贡献达到了10%~20%;考虑到盛行风向对污染物传输的影响,需谨慎在京津冀西北方向、长三角周边以及珠三角以北方向的较近区域新建燃煤电厂或大型燃煤火电基地;按照既定的煤炭消费总量控制目标(42×108 t)估算,2020年新增燃煤电厂容量可以满足电力消费需求增量的70%,“十三五”期间仍需要进一步开发其他替代能源,煤炭消费总量控制对煤电发展的影响逐渐减弱;中东部地区可增加燃煤火电装机容量较小,华北平原、长三角、珠三角和四川盆地等地区应禁止新建煤电机组,新疆维吾尔自治区、内蒙古自治区西部、宁夏回族自治区、陕西省北部等西部地区将是未来燃煤火电发展空间最大的区域.   相似文献   
992.
Fish from the Great Lakes contain polychlorinated biphenyls(PCBs)which have been shown to disrupt endocrine function and mimic thyroid hormones,but they also contain beneficial omega-3 fatty acids that may offer protection against endocrine cancers.The purpose of this study was to examine the effects of Lake Ontario fish consumption and the estimated consumption of PCBs and omega-3 fatty acids on the risk of thyroid cancer in a group of sport fishermen.Anglers from the New York State Angler Cohort Study were followed for cancer incidence from 1991–2008.Twenty-seven cases of incident thyroid cancer and 108 controls were included in the analyses.Total estimated fish consumption,estimated omega-3 fatty acid consumption,and estimated PCB consumption from Lake Ontario fish were examined for an association with the incidence of thyroid cancer,while matching on sex,and controlling for age and smoking status.Results from logistic regression indicate no significant associations between fish consumption,short-term estimated omega-3 fatty acids,or estimated PCB consumption from Great Lakes fish and the development of thyroid cancer,but it was suggested that long-term omega-3 fatty acid from Great Lakes fish may be protective of the development of thyroid cancer.In conclusion,fish consumption,with the possible concomitant PCBs,from the Great Lakes does not appear to increase the risk of thyroid cancer in New York anglers.Further research is needed in order to separate the individual health effects of PCBs from omega-3 fatty acids contained within the fish.  相似文献   
993.
Microorganisms are involved in a variety of biogeochemical processes in natural environments. The differences between bacterial communities in freshwaters and upslope soils remain unclear. The present study investigated the bacterial distribution in a plateau freshwater lake, Erhai Lake (southwestern China), and its upslope soils. Illumina MiSeq sequencing illustrated high bacterial diversity in lake sediments and soils. Sediment and soil bacterial communities were mainly composed of Proteobacteria, Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi and Planctomycetes. However, a distinctive difference in bacterial community structure was found between soil and sediment ecosystems. Water content, nitrogen and pH affected the distribution of the bacterial community across Erhai Lake and its upslope soils. Moreover, the soil bacterial community might also be shaped by plant types. This work could provide some new insights into plateau aquatic and terrestrial microbial ecology.  相似文献   
994.
电力、钢铁、化工等行业,是我国能源消耗大户,也是生态环境的最主要污染源。针对上述行业,以烟尘、SO2、NOX等主要污染物为重点控制对象,研发智能化烟气多污染物治理系统;同时,通过提升环保治理装置的智能化水平,改善运行性能,节能降耗。运用系统智能化技术,达到多污染物协同治理,提高运行管理水平和应对波动的响应能力,提高核心工艺、核心设备的国产化率,突破国外厂商在高端智能化设备上的垄断和封锁,对整个环保产业的转型升级,推动产业发展具有重要的意义。  相似文献   
995.
李捷  于翔  隋军 《环境工程》2016,34(10):17-20
以某MBR城市污水处理厂为研究对象,在现状运行的基础上,通过改变供氧方式、进水方式、内循环量及生化池的运行工况,对各方案的运行效果进行全面的水质跟踪监测,并对各方案的运行能耗进行对比分析。结果显示:在MBR工艺中,缺氧环境的增加和进水方式的调整,可提高系统的脱氮效能;适当增加膜池的回流量、同时调整好氧池的运行工况,可将膜吹扫产生的溶解氧进行再利用。建议污水处理厂实际运行过程中,结合进水水质、水量的变化,调整不同运行工况,从而强化系统对污染物的去除能效,同时降低运行能耗。  相似文献   
996.
焦化废水产生于煤炭的不完全气化过程,其水质成分复杂,处理工艺技术单元多、水力停留时间长且存在多指标目标,处理过程需消耗大量能量,从若干工程实践中发现,影响焦化废水处理工程运行能耗的因素主要包括水质特性、工艺流程、运行时间、设备状况等,系统分析这些因素对运行能耗的贡献,了解耗能规律并模型化,可为焦化废水处理工程设计提供节能依据.本研究以好氧/水解/好氧(OHO)流化床工艺为核心的实际焦化废水处理工程为案例,根据耗能设备、处理目标和单元功能不同将整个处理工程分解为气浮、废水输送、泥渣输送、鼓风曝气、混合、脱水、加药、公用的8个耗能系统,分别分析各系统的耗能因子,建立模型,加权得到总能耗模型;然后分别用HRT(停留时间)法和24 h法计算能耗值,与实际24 h读表电耗值相比较评价模型的准确性.分析结果表明,焦化废水处理工程总运行能耗与进水水量、污泥量、溶解氧、硝化液回流比、进水COD、进水总氮浓度的相关性强;HRT法与24 h法得到的能耗值与实际24 h读表能耗值呈显著线性关系,R2分别为0.93和0.97,相对误差分别为4.28%~19.18%和3.45%~8.94%,模型分析值与工程实测值吻合度比较好,表明模型准确可靠.因此认为,基于耗能单元系统建立的工程系统总能耗模型可以用于预测因水质特性、工艺流程、设备条件等变化的实际工程运行总能耗,得到了建立焦化废水处理工程单元解析模型的系统性新方法.  相似文献   
997.
Environmental attitudes are considered to be important factors that influence sustainable consumption. Typically, attitudes fall into two main types: a general environmental attitude (GEA) and a specific environmental attitude (SEA). This study found that the effect of the SEA is stronger than the GEA in regard to sustainable consumption behavior. Also, when analyzing the purchasing behavior of green products, the SEA is a more appropriate and consistent predictor of behavior than the GEA. The study suggests a more operationalized and salient definition of the intended meaning of the term “environmental attitude,” and also advises researchers and marketing professionals to use a framework that contains both types of environmental attitudes in order to better understand what drives the attitude–behavior gap in green consumer behavior.  相似文献   
998.
While a small set of economic activities generates most of the direct environmental burdens, the complexity of connections within an economic system requires consideration of the effects caused by the interdependences between its different agents. To date, however, the input–output (I–O) subsystems literature has been limited to uncovering the intersectoral linkages of direct and indirect environmental impacts within an economy and the connections between sectors and private consumption have thus not attracted much attention. This paper proposes an I–O subsystems model that endogenously incorporates not only production sectors but also household consumption to capture the entire channel of environmental impacts. The empirical application focuses on carbon dioxide equivalent (CO2-eq.) emissions and water use associated with production sectors and households defined in the I–O table for a Spanish region, Extremadura. The results highlight the key role of the effects induced by private consumption on the environmental burdens of services.  相似文献   
999.
Mining is a water intensive activity, and reducing water consumption is a key requirement in moving toward a more sustainable mining industry. This paper identifies mine water reduction, reuse and recycle options, and demonstrates cases where these options have been implemented around the world. A mine water system model is developed and used to show potential water saving strategies through six scenarios. Apart from the base case, these scenarios include the introduction of evaporation reduction strategies, paste tailings disposal, filtered tailings disposal, ore pre-sorting and a combination of the most effective options. The results of the modeling show how an open-pit copper mine with a traditional layout can move from having an average water withdrawal of 0.76 m3/t of ore processed to 0.20 m3/t of ore processed or lower. A key result of the modeling is the discovery that a combination of ore pre-concentration and filtered tailings disposal can reduce water consumption by 74% or more. This finding demonstrates an opportunity to significantly lower water consumption on mine sites.  相似文献   
1000.
通过设定三级分析指标,对经济发展与资源消耗、污染物排放、工业污染治理投资定量对比分析的基础上,研究1999年-2009年间内蒙古经济发展和环境现状。结果表明,近十年间内蒙古以化石能源消费为主的高耗能工业占主导地位,能源消费支撑了经济发展,二氧化硫减排压力依然艰巨。通过生态承载能力分析,内蒙古区域生态赤字呈逐年增加态势,生态压力指数加大,但处于可控状态,对地区生态影响最大的依然是农耕、农牧经济,化石能源和建筑用地人均生态足迹增幅最大,应引起高度重视。  相似文献   
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