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1.
燃煤锅炉湿法脱硫烟气中颗粒物排放特征   总被引:2,自引:1,他引:1  
选择北京市典型燃煤锅炉进行研究,结果表明:烟气中可凝结颗粒物在总颗粒物中占有较高比例,供热燃煤锅炉总颗粒物排放水平明显高于电厂燃煤锅炉;颗粒物中水溶性离子含量较高,供热燃煤锅炉硫酸根比例尤其显著;烟气总颗粒物中存在大量不稳定的易被氧化的组分;同为燃煤源,不同的烟气净化工艺排放的PM2.5组分特征差异明显;现有标准和技术规范存在不足,无法满足全面、准确监测污染源排放总颗粒物的实际需要。建议建立总颗粒物、可凝结颗粒物的监测技术规范,全面测算燃煤锅炉硫、氮化合物排放情况,科学评估脱硫及脱硝效率。  相似文献   

2.
根据《煤电节能减排升级与改造行动计划》以及《国家环境保护"十三五"规划纲要》,我国燃煤电厂污染物排放浓度应达到现行燃气锅炉标准,现行颗粒物监测仪器需要进行更新。现在市面上有2种污染源颗粒物采样管可对改造后电厂进行颗粒物采样监测,采用平行实验法对这2种采样管所采集的颗粒物质量结果进行分析,同时使用验证实验分析2种采样管颗粒物采集质量结果产生差异的原因,并对如何提升燃煤电厂颗粒物监测的准确性提出建议。  相似文献   

3.
The morphology, microstructure, and chemical composition of a variety of particles emitted from coal-fired power plants, steel plants, and vehicle exhausts, which are possible sources of particulate matter (PM) in the atmosphere, were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and compared with particle samples collected from urban atmosphere to identify the best footprint or the suitable indicator relating the existence of studied particles and their possible emitters by the morphology, microstructure, and chemical composition of the particles. The investigation indicated that the particles from these three sources are different in morphology, microstructure, and chemical composition. Sphere aggregates were generally the most abundant components, with silicon and aluminum as major elements. The urban air particulate contained particles similar to those observed in the power plant, steel plant, and vehicle exhaust samples suggesting that all three sources are contributing to the pollution in the city.  相似文献   

4.
Coal combustion in the power sector gives rise to the emission of primary and secondary particulate pollutants. Since the emission of pollutants depends on coal quality and combustion technology, and given that transport, transformation and deposition of contaminants depend on regional climatic conditions, specific studies for the power stations is needed to evaluate their environmental impacts. Monitoring of ambient respirable suspended particulate matter (RSPM) and suspended particulate matter (SPM) levels around a large coal-fired power station in India was carried out. The specific objectives were the determination of spatial and seasonal variability in RSPM and SPM levels, and their relationship with meteorological parameters such as wind velocity and relative humidity. The results have shown a marked seasonal trend and spatial variability in RSPM and SPM levels in the study area. Higher concentrations of ambient RSPM and SPM were found in downwind monitoring stations compared to upwind direction. Ratios of RSPM to SPM and correlation coefficient values between RSPM and SPM along with meteorological parameters were also worked out. Relative humidity and wind velocity have shown an inverse relation with particulate deposition pattern.  相似文献   

5.
Pollutants such as sulfur would concentrate in the source regions and thus the localized impacts are more obvious. Local balance of electricity by transporting coal has resulted in dense concentration of coal-fired power plants in load centers and caused severe environmental problems. Electricity relocation through interregional transmission is another choice for energy transportation to achieve electricity balance across regions and pollution mitigation. Using interregional electricity transmission (IRET) lines in China as a quasi-natural experiment, this paper assesses the environmental impact of electricity relocation. In the assessment, the grid organization of “province as executor” in China is considered because it affects the sphere of IRET's influence on pollution mitigation. Here we show the environmental benefits of electricity relocation. We find that, electricity relocation through interregional transmission leads to the growth rate of sulfur dioxide (SO2) emission decreasing 7% in landing areas and Sichuan province benefits most from electricity relocation. It is interesting that there is no significant increase of SO2 emission growth rate in sending areas compared to counterfactuals if there had no IRET due to more integration of clean energy and improved emission efficiency in sending areas. Placebo study and robustness check show that the results are quite convincing. Therefore, IRET provides an appealing choice for China's environmental control in eastern region, and it is not necessarily at the cost of pollution in western region. The methodology can be applied to assess the environmental impacts of other program or policy elsewhere.  相似文献   

6.
Lignite mining operations and lignite-fired power stations result in major particulate pollution (fly ash and fugitive dust) problems in the areas surrounding these activities. The problem is more complicated, especially, for urban areas located not far from these activities, due to additional contribution from the urban pollution sources. Knowledge of the distribution of airborne particulate matter into size fraction has become an increasing area of focus when examining the effects of particulate pollution. On the other hand, airborne particle concentration measurements are useful in order to assess the air pollution levels based on national and international air quality standards. These measurements are also necessary for developing air pollutants control strategies or for evaluating the effectiveness of these strategies, especially, for long periods. In this study an attempt is made in order to investigate the particle size distribution of fly ash and fugitive dust in a heavy industrialized (mining and power stations operations) area with complex terrain in the northwestern part of Greece. Parallel total suspended particulates (TSP) and particulate matter with an aerodynamic diameter less than 10 μm (PM10) concentrations are analyzed. These measurements gathered from thirteen monitoring stations located in the greater area of interest. Spatial, temporal variation and trend are analyzed over the last seven years. Furthermore, the geographical variation of PM10 – TSP correlation and PM10/TSP ratio are investigated and compared to those in the literature. The analysis has indicated that a complex system of sources and meteorological conditions modulate the particulate pollution of the examined area.  相似文献   

7.
The paper presents two aspects concerned with the mercury air emission inventory from coal-fired public power and energy plants: an uncertainty analysis, using Monte Carlo simulation (Journal of the American Statistical Association, 44(247), 335–341 1949) and the monthly distributions applying the Denton-Cholette approach (Dagum & Cholette 2006). The analysis determines uncertainty about the estimates mercury air emission from 1990 to 2012 including the development of air pollution control (APC) technologies in the Polish public power and energy sector, also the monthly distributions in comparison with previously obtained results (H?awiczka 2008). The uncertainty of mercury (Hg) content in fuel is 31.6% for hard coal and 42.4% for brown coal. The confidence interval for the estimated emission changed from [kg] (16,082.2; 16,242.2) in 1990 to (10,525.9;10,671.1) in 2012. However, the Denton-Cholette approach overestimates the emissions for the warmer periods of the year, but it could, however, in our view, be applied to attain the monthly distributions.  相似文献   

8.
Strategies to conserve biodiversity need to include the monitoring, modelling, adaptation and regulation of the composition of the atmosphere. Atmospheric issues include climate variability and extremes; climate change; stratospheric ozone depletion; acid deposition; photochemical pollution; suspended particulate matter; and hazardous air pollutants. Coarse filter and fine filter approaches have been used to understand the complexity of the interactions between the atmosphere and biodiversity. In the first approach, climate-based models, using GIS technology, helped create future biodiversity scenarios under a 2 × CO2 atmosphere. In the second approach, the SI/MAB forest biodiversity monitoring protocols helped calibrate the climate-forest biodiversity baseline and, as global diagnostics, helped identify where the biodiversity was in equilibrium with the present climate. Forest climate monitoring, an enhancing protocol, was used in a co-location approach to define the thermal buffering capacity of forest ecosystems and their ability to reduce and ameliorate global climate variability, extremes and change.  相似文献   

9.
颗粒物激光雷达在大气复合污染立体监测中的应用   总被引:4,自引:4,他引:0  
针对由于局地污染、沙尘输入、外源性输入与局地污染物相互叠加所导致的3种灰霾污染发生过程,分别选取3个典型案例,采用颗粒物激光雷达对污染物的时空分布特征进行解析。研究发现,在局地污染发生时,污染物从地面开始垂直向上扩散,扩散高度约1 km。重度污染过程中,气溶胶的日均垂直消光系数随高度的变化背离指数衰减特征,800 m高度处出现消光系数的极大值层,极大值超过2.5 km-1,800 m以下消光系数近乎常数,约为0.3 km-1。这说明,重污染过程中,有一层较厚重的颗粒物分布,使近地面污染物在垂直方向的扩散能力减弱,形成积累效应,造成大面积空气混浊。当有外源性沙尘输入时,激光雷达能够清晰地监测到污染团输入的全过程。沙团突然出现在高空2~3 km。污染团退偏振度较大,超过0.3。随着沙尘粒子的重力沉降,沙团的轮廓在垂直方向上不断地增大。沙团的输入,导致近地面粗颗粒质量浓度的增加幅度明显大于细颗粒。在第3个案例中,激光雷达清晰地监测到高空1.8~3 km突然出现含有大量球形细颗粒的污染团,同时还发现此污染团与近地面的污染物有不同的演化特征。近地面污染物随时间垂直向上扩散,12:00左右扩散高度超过1.8 km。而高空的污染团逐渐沉降进入边界层内,与近地面扩散的污染物相互混合,共同导致本地的灰霾天气。综上所述,激光雷达可以清晰地捕获污染物的垂直结构特征,对不同的致霾过程进行立体解析,实现对大气复合污染的监测和机理研判。  相似文献   

10.
灰霾期间气溶胶的污染特征   总被引:11,自引:0,他引:11  
从颗粒物的时空分布和浓度水平方面综述了灰霾期间气溶胶的污染特征,介绍了灰霾期间气溶胶中金属元素、水溶性离子、有机碳和元素碳的浓度特征,以及颗粒物与能见度的相关性研究进展。指出:灰霾天气多发生在冬季,且气溶胶中PM2.5占的比重大;气溶胶污染与地理环境、气候条件、经济发展水平等有密切关系;水溶性离子多集中在PM2.5中;能见度的下降与气溶胶特别是细颗粒物有很大关系。提出目前灰霾研究中主要存在3大问题:一是对灰霾期间气溶胶中含有的有机物类别及其对不同季节发生灰霾的贡献率仍需进一步研究;二是灰霾期间气溶胶中有机物的形成机理尚不明确;三是不同源排放的气溶胶对灰霾形成的贡献率有待探讨。建议系统地开展大气细颗粒物有害成分的鉴定、源排放颗粒物的物理化学特性、扩散过程中各种物质间的反应和转化等方面的研究,为大气污染防治法规的制定提供依据。  相似文献   

11.
利用SPAMS 0515于2015年1月在盘锦市兴隆台空气质量自动监测点位采集PM_(2.5)样品,并分析其污染特征和来源。研究结果表明,盘锦市冬季PM_(2.5)的颗粒类型主要以OC颗粒、富钾颗粒、EC颗粒组成。其中,OC颗粒占比最高,为52.5%;PM_(2.5)污染的主要贡献源为燃煤、生物质燃烧、机动车尾气排放,占比分别为33.2%、25.7%、17.5%,特别是在PM_(2.5)质量浓度较高时段,燃煤和机动车尾气排放对污染的贡献较大。  相似文献   

12.
This paper presents the assessment of gaseous and particulate emissions from thermal power plants operating on different combustion technologies. Four thermal power plants operating on heavy furnace oil were selected for the study, among which three were based on diesel engine technology, while the fourth plant was based on oil-fired steam turbine technology. The stack emissions were monitored for critical air pollutants carbon monoxide, carbon dioxide, oxides of nitrogen, sulfur dioxide, particulate matter, lead, and mercury. The pollutant emissions were measured at optimum load conditions for a period of 6 months with an interval of 1 month. The results of stack emissions were compared with National Environmental Quality Standards of Pakistan and World Bank guidelines for thermal power plants, and few parameters were found higher than the permissible limits of emissions. It was observed that the emissions carbon monoxide, oxides of nitrogen, and particulate matters from diesel engine-based power plants were comparatively higher than the turbine-based power plants. The emissions of sulfur dioxide were high in all the plants, even the plants with different technologies, which was mainly due to high sulfur contents in fuel.  相似文献   

13.
There is enough scientific evidence that associates air pollution by particulate matter (PM) with negative impacts on health. However, one-third of the world's population uses highly polluting fuels for cooking, heating, or lighting, especially in low- and middle-income countries. Due to the above, the environmental authorities of most of the countries have established different short-, medium-, and long-term regulations to reduce this pollution. It should be noted that it is challenging to identify the real effectiveness of this type of regulation since it is necessary to determine whether the pollution was reduced exclusively by the implementation of that regulation or due to other confusing factors. To address this issue, the present study performs an ex - post evaluation of the Critical Episodes Management program that imposes restrictions on the use of firewood heaters during pre-emergency and emergency episodes to reduce air pollution in the short-term in the city of Temuco, Chile (one of the most polluted cities in Latin America). Specifically, a fixed-effects panel data regression is applied to hourly concentrations of particulate matter data, controlling by meteorological and seasonal factors. The results show that restrictions on the use of firewood heaters generate a significant reduction in PM10 and PM2.5 concentrations during pre-emergency episodes (9.2% and 17.5%) and emergency episodes (5.9% and 16.3%). Thus, it can be concluded that this program is useful, but it must be complemented by others medium- and long-term environmental programs.  相似文献   

14.
选取上海市7家未安装气-气换热器的国控燃煤电厂作为研究对象,从煤质、除尘器、脱硫协同脱除作用以及锅炉工况负荷等方面探讨对颗粒物浓度排放系数 K值产生的影响,得出上述因素通过改变脱硫进口颗粒物浓度值影响 K值,当脱硫进口颗粒物浓度较低、波动范围较小时,其 K值也维持相对稳定的状态;当脱硫进口颗粒物浓度较高、波动范围较大时,其 K值也会发生较大的变化等结论。  相似文献   

15.
Seaports are major hubs of economic activity and of environmental pollution in coastal urban areas. Due to increasing global trade, transport of goods through ports has been steadily increasing and will likely continue to increase in the future. Evaluating air pollution impacts of ports requires consideration of numerous sources, including marine vessels, trucks, locomotives, and off-road equipment used for moving cargo. The air quality impacts of ports are significant, with particularly large emissions of diesel exhaust, particulate matter, and nitrogen oxides. The health effects of these air pollutants to residents of local communities include asthma, other respiratory diseases, cardiovascular disease, lung cancer, and premature mortality. In children, there are links with asthma, bronchitis, missed school days, and emergency room visits. The significance of these environmental health impacts requires aggressive efforts to mitigate the problem. Approaches to mitigation encompass a range of possibilities from currently available, low-cost approaches, to more significant investments for cleaner air. Examples of the former include restrictions on truck idling and the use of low-sulfur diesel fuel; the latter includes shore-side power for docked ships, and alternative fuels. A precautionary approach to port-related air pollution would encourage local production of goods in order to reduce marine traffic, greener design for new terminals, and state-of-the art approaches to emissions-control that have been successfully demonstrated at ports throughout the world.  相似文献   

16.
空气细颗粒物(PM_(2.5))污染已成为影响人体健康的重要因素,其健康效应及致炎症机制已经受到人们的广泛关注。简述了PM_(2.5)国内外污染现状,从PM_(2.5)的质量浓度和组成成分2个方面系统地阐述了其对人体健康的危害,并重点从介导信号通路和介导细胞自噬2个方面对PM_(2.5)导致机体炎症反应的毒性机制进行了总结和讨论,为后续研究和控制PM_(2.5)对机体健康的危害提供科学参考。  相似文献   

17.
为探究燃煤电厂周边大气环境中重金属的污染特征与来源,对广东某山区燃煤电厂周边地区环境和污染源的重金属进行测定,分析其污染特征,采用因子分析法和Pb同位素示踪法对环境中的重金属进行来源解析。结果表明,研究区域室内积尘中重金属浓度水平明显高于土壤重金属,污染空间分布与当地气象条件相关。环境空气TSP中重金属主要来自2个污染源,Cd、Pb、As主要来自电厂燃煤,Ca、Mn、Al、Mg主要来自土壤扬尘。TSP、降尘、积尘样品所含的Pb均与电厂采集的煤、炉渣、粉煤灰样品所含的Pb具有同源性,与其他污染源同源性不明显,说明研究区域大气中Pb污染主要来自电厂燃烧所排放的烟尘,其他污染源影响不大。  相似文献   

18.
广州市空气可吸入性颗粒物的污染水平   总被引:10,自引:1,他引:9  
报告了中美合作“广州市大气污染对儿童肺功能影响研究”课题可吸入性颗粒物的两年监测结果。用安德森双道采样器、Teflon膜采集细颗粒物(<25μm,PM25)和粗颗粒物(25≤<10μm,PM2510),两者之和为PM10,每季度采15天,每天采一个24小时样品。结果表明,广州市城区大气可吸入性颗粒物的污染相当严重,尤其是细颗粒物(PM25)的污染,应引起公众和政府有关部门的重视。  相似文献   

19.
采用2015—2017年秋、冬季江苏省环境空气质量监测数据,从空气质量优良(达标)率、首要污染物、主要污染物浓度分析空气质量现状及特点。结果表明,江苏省秋、冬季空气质量优良(达标)率在60%左右,其中沿海地区空气质量达标率最高(71.1%),西北地区达标率最差(52.2%)。污染日的首要污染物主要为PM 2.5,占比高达91.5%。ρ(PM2.5)/ρ(PM 10)存在地区差异,江苏西北地区扬尘源贡献较大,江苏南部地区的二次颗粒物贡献更明显。ρ(NO2)/ρ(SO2)逐年持续升高,表明大气污染类型从燃煤性污染转变为复合型污染。  相似文献   

20.
燃油和燃煤电厂排放可吸入颗粒物的物理化学特性   总被引:2,自引:1,他引:1  
分别对燃烧重油与烟煤两个电厂排放可吸入颗粒物的显微结构、颗粒类型及重金属在可吸入颗粒物中分布特征进行研究.研究表明,燃煤电厂排放可吸入颗粒物的形态都以球形颗粒为主,而燃油电厂排放可吸入颗粒物由一些絮状物和类似于燃煤飞灰中球形颗粒组成.根据可吸入颗粒物的化学组成,发现燃油电厂排放可吸入颗粒物的颗粒类型有硅铝质和钙-硅铝质...  相似文献   

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