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941.
欧盟航空碳税对中国的影响及应对建议   总被引:1,自引:0,他引:1  
尽管始终备受争议的航空碳税计划终于在欧盟内外的双重压力之下面临流产,但是建立全球碳排放交易体系终究是大势所趋,中国在这一问题上应该有前瞻性.由于欧盟航空碳税同环保高度相关,本文通过资料调研及数据收集,对欧盟此举的主要原因和对中国的影响进行了分析,并从保护航空业竞争力、介入全球碳排放交易体系设计和我国环保工作实际出发提出了应对建议.  相似文献   
942.
排污权交易的实践证明了排污权交易可以有效地保护环境,同时也提出了亟需对其适用条件和建设模式进行探索的现实命题。文章以合芜蚌自主创新试验区为例,在分析了合芜蚌试验区内推行排污权交易制度的可行性基础上,提出了区域性排污权交易的构建模式。  相似文献   
943.
基于改进IPAT模型的中国未来碳排放预测   总被引:7,自引:1,他引:6  
杜强  陈乔  陆宁 《环境科学学报》2012,32(9):2294-2302
在"碳排放量与能源消费成正比"假设的基础上,对中国1987—2010年的历年碳排放量和人均碳排放量进行了分区域研究与计算.经数据分析,发现以2002年为界线,前后两个时期中国碳排放变化缺乏内在的连贯性,2002年以前的碳排放曲线无法表征未来年份碳排放趋势.在此发现的基础上,以2002—2010年碳排放数据为基础,引入表征科技进步的变量,对IPAT模型进行改进,进而对2010—2050年中国碳排放进行了预测和分析.结果表明:中国排放峰值发生在2030年,全国碳排放总量将达到3684.1636Gg,人均碳排放为2.6476t;在2030年之前中国碳排放量将以平均每年2.89%的速度持续增加.2030—2050年碳排放量将以每年2.09%的速度减少,至2050年,全国碳排放量为2366.4522Gg,人均碳排放为1.8521t.本研究为中国未来碳排放政策的制定提供了方法与数据支持.  相似文献   
944.
The aim of this study was to evaluate whether unburned carbon particles present in fly ash can help in the retention of S, Cl, Br, As, Se, Cu, Ni, Zn, Ga, Ge, Rb, and Pb out of flue gas during the coal combustion at fluidised-bed power station where the coal was combusted along with limestone. The competitive influence of 10%-25% CaO in fly ashes on the distribution of studied elements was studied as well to be clear which factor governs behaviour of studied elements. Except of S (with significant association with CaO) and Rb and Pb (with major affinity to Al2O3) the statistically significant and positive correlation coefficients were calculated for the relations between unburned carbon content and Br (0.959), Cl (0.957), Cu (0.916), Se (0.898), Ni (0.866), As (0.861), Zn (0.742), Ge (0.717), and Ga (0.588) content. The results suggest that the unburned carbon is promising material in terms of flue gas cleaning even if contained in highly calcareous fly ashes.  相似文献   
945.
张辉  贾思宁  范菁菁 《环境工程》2012,(3):59-62,30
SO2、NOx和CO2是燃气和燃煤电厂排放的主要大气污染物,以三种污染物排放估算方法为基础,比较了几种机组容量下,燃气机组和燃煤机组污染物的排放量。结果表明:燃气电厂因其在环境保护方面的显著优越性,是解决电站环境污染的重要出路。  相似文献   
946.
The real-world fuel efficiency and exhaust emission profiles of CO, HC and NOx for light-duty diesel vehicles were investigated. Using a portable emissions measurement system, 16 diesel taxies were tested on different roads in Macao and the data were normalized with the vehicle specific power bin method. The 11 Toyota Corolla diesel taxies have very good fuel economy of (5.9 ± 0.6) L/100 km, while other five diesel taxies showed relatively high values at (8.5 ± 1.7) L/100 km due to the variation in transmission systems and emission control strategies. Compared to similar Corolla gasoline models, the diesel cars confirmed an advantage of ca. 20% higher fuel efficiency. HC and CO emissions of all the 16 taxies are quite low, with the average at (0.05 ± 0.02) g/km and (0.38 ± 0.15) g/km, respectively. The average NOx emission factor of the 11 Corolla taxies is (0.56 ± 0.17) g/km, about three times higher than their gasoline counterparts. Two of the three Hyundai Sonata taxies, configured with exhaust gas recirculation (EGR) + diesel oxidation catalyst (DOC) emission control strategies, indicated significantly higher NO2 emissions and NO2/NOx ratios than other diesel taxies and consequently trigger a concern of possibly adverse impacts on ozone pollution in urban areas with this technology combination. A clear and similar pattern for fuel consumption and for each of the three gaseous pollutant emissions with various road conditions was identified. To save energy and mitigate CO2 emissions as well as other gaseous pollutant emissions in urban area, traffic planning also needs improvement.  相似文献   
947.
基于2005—2010年SO2排放量和经济发展数据,对该时段的SO2排放环境负荷变化进行分析并以此数据构建了新疆三大地区万元产值SO2排放量随人均GDP变化的环境学习曲线;以所建立的环境学习曲线为依据,分析2005—2010年万元产值SO,的减排潜力,并对新疆“十二五”期间不同地区万元SO2的节能减排潜力进行了预测。结果表明:经济发展水平越高的地区,万元产值SO2排放环境负荷越小,减排潜力越小;经济发展水平越低的地区,万元产值SO2排放环境负荷越大,减排潜力也越大。研究结果将为“十二五”自治区SO2排放总量控制及减排指标提供科学依据。  相似文献   
948.
In the present article we characterized the emissions at the exhaust of a Common Rail (CR) diesel engine, representative of lightduty class, equipped with a catalyzed diesel particulate filter (CDPF) in controlled environment. The downstream exhausts were directly analyzed (for PM, CO, CO2, O2, HCs, NOx) by infrared and electrochemical sensors, and SEM-EDS microscope; heavy metals were chemically analyzed using mosses and lichens in bags, and glass-fibre filters all exposed at the engine exhausts. The highest particle emission value was in the 7–54 nm size range; the peak concentration rose until one order of magnitude for the highest load and speed. Particle composition was mainly carbonaceous, associated to noticeable amounts of Fe and silica fibres. Moreover, the content of Cu, Fe, Na, Ni and Zn in both moss and lichen, and of Al and Cr in moss, was significantly increased. Glass-fibre filters were significantly enriched in Al, B, Ba, Cu, Fe, Na, and Zn. The role of diesel engines as source of carbonaceous nanoparticles has been confirmed, while further investigations in controlled environment are needed to test the catalytic muffler as a possible source of silica fibres considered very hazardous for human health.  相似文献   
949.
餐饮废弃油脂的生物柴油生命周期能耗与CO_2排放分析   总被引:2,自引:1,他引:1  
对以餐饮废弃油脂为原料,利用化学催化法生产的生物柴油进行了生命周期能耗与CO2排放分析,以具有1 MJ能量的生物柴油产品为功能单位.结果表明:生物柴油生命周期总能耗为1.648 9 MJ,化石能耗为0.616 9 MJ,化石能效比为1.62,生命周期净能量产出为0.383 1 MJ,生命周期CO2净排放量为-10.34 g.与生产和使用1 MJ能量的石化柴油相比,生物柴油生命周期总能耗升高37%,化石能耗降低49%,可减少CO2排放90.99 g.  相似文献   
950.
Many studies on methane emissions from animal manure have revealed that animal manure is a major source of methane emissions to the atmosphere that can have negative consequences for people,animals and environment.In general,the release of methane can be influenced by the type of feed taken by animals,temperature,manure characteristics and so on.This study aimed at quantifying and comparing methane release from dairy manure with different piling treatments.Four treatments were designed including manure piling height 30,45,60 cm and adding 6 cm manure every day until the piling height was 60 cm.Static chamber method and gas chromatography were adopted to measure the methane emissions from April to June in 2009.Methane emission rates of all four manure treatments were low in the first week and then increased sharply until reaching the peak values.Subsequently,all the methane emission rates decreased and fluctuated within the steady range till the end of the experiment.Wilcoxon nonparametric tests analysis indicated that methane emission rate was greatly influenced by manure piling height and manner.There were no significant relationships between methane emission rates and the temperatures of ambience and heap.However,regression analysis showed that the quadratic equations were found between emission rates of all treatments and the gas temperature in the barrels.  相似文献   
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