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在分析沈阳市NOx排放现状及发展趋势基础上,针对NOx总量控制工作中存在基础薄弱、污染物增量大、治理技术上存在不确定因素等实际问题,总结了"增量控制,存量削减"的总体工作思路,并提出了实施电力企业脱硝工程改造的对策和建议. 相似文献
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通过利用挥发回转窑处置钢丝绳行业污泥的工业化试验,测定了烟气排放参数及污染物排放指标,分析了污泥添加对挥发回转窑烟气排放的影响程度及各项污染物指标之间的相关性。结果表明,污泥添加量18%~22%,对挥发回转窑烟气排放无影响,烟尘、SO2、氮氧化物、Zn、Pb、HCl等各项污染物指标均符合国家控制标准;烟尘排放浓度与Pb、Zn排放浓度呈显著正相关;SO2排放浓度与烟气含氧量、空气过剩系数、排放浓度呈显著负相关。通过控制烟气中烟尘浓度可减少Zn、Pb的排放,在满足SO2排放浓度达标的同时,还应加强工艺供氧量的管理,控制的产生,减少烟气对生产设备的腐蚀。 相似文献
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Field monitoring of volatile organic compounds using passive air samplers in an industrial city in Japan 总被引:4,自引:1,他引:3
Kume K Ohura T Amagai T Fusaya M 《Environmental pollution (Barking, Essex : 1987)》2008,153(3):649-657
Highly portable, sensitive, and selective passive air samplers were used to investigate ambient volatile organic compound (VOC) levels at multiple sampling sites in an industrial city, Fuji, Japan. We determined the spatial distributions of 27 species of VOCs in three campaigns: Mar (cold season), May (warm season), and Nov (mild season) of 2004. In all campaigns, toluene (geometric mean concentration, 14.0microg/m3) was the most abundant VOC, followed by acetaldehyde (4.76microg/m3), and formaldehyde (2.58microg/m3). The spatial distributions for certain VOCs showed characteristic patterns: high concentrations of benzene and formaldehyde were typically found along major roads, whereas high concentrations of toluene and tetrachloroethylene (PCE) were usually found near factories. The spatial distribution of PCE observed was extremely consistent with the diffusion pattern calculated from Pollutant Release and Transfer Register data and meteorological data, indicated that passive air samplers are useful for determining the sources and distributions of ambient VOCs. 相似文献
28.
An air quality sampling program was designed and implemented to collect the baseline concentrations of respirable suspended
particulates (RSP = PM10), non-respirable suspended particulates (NRSP) and fine suspended particulates (FSP = PM2.5). Over a three-week period, a 24-h average concentrations were calculated from the samples collected at an industrial site
in Southern Delhi and compared to datasets collected in Satna by Envirotech Limited, Okhla, Delhi in order to establish the
characteristic difference in emission patterns. PM2.5, PM10, and total suspended particulates (TSP) concentrations at Satna were 20.5 ± 6.0, 102.1 ± 41.1, and 387.6 ± 222.4 μg m−3 and at Delhi were 126.7 ± 28.6, 268.6 ± 39.1, and 687.7 ± 117.4 μg m−3. Values at Delhi were well above the standard limit for 24-h PM2.5 United States National Ambient Air Quality Standards (USNAAQS; 65 μg m−3), while values at Satna were under the standard limit. Results were compared with various worldwide studies. These comparisons
suggest an immediate need for the promulgation of new PM2.5 standards. The position of PM10 in Delhi is drastic and needs an immediate attention. PM10 levels at Delhi were also well above the standard limit for 24-h PM10 National Ambient Air Quality Standards (NAAQS; 150 μg m−3), while levels at Satna remained under the standard limit. PM2.5/PM10 values were also calculated to determine PM2.5 contribution. At Satna, PM2.5 contribution to PM10 was only 20% compared to 47% in Delhi. TSP values at Delhi were well above, while TSP values at Satna were under, the standard
limit for 24-h TSP NAAQS (500 μg m−3). At Satna, the PM10 contribution to TSP was only 26% compared to 39% in Delhi. The correlation between PM10, PM2.5, and TSP were also calculated in order to gain an insight to their sources. Both in Satna and in Delhi, none of the sources
was dominant a varied pattern of emissions was obtained, showing the presence of heterogeneous emission density and that nonrespirable
suspended particulate (NRSP) formed the greatest part of the particulate load. 相似文献
29.
This study deals with the emission of methane in relation to changing environmental conditions and human impact, in three
mangrove ecosystems of south India. Time-varying fluxes of methane adopting the close chamber technique were used to estimate
CH4 emission from an unpolluted site (Pichavaram mangroves) and two polluted sites viz. (1) Ennore Creek mangroves (affected
by fertilizer effluents and crude oil discharges) and (2) Adyar estuary mangroves (affected by the discharges of organic and
industrial wastes), covering monthly and seasonal variations. The results indicate annual average CH4 emissions of 7.4, 5.02 and 15.4 mg m−2 h−1 from the sediment–water interface of the Pichavaram, Ennore Creek and Adyar estuary respectively. Emission characteristics
obtained at Pichavaram mangroves represent a natural variability with changing physico-chemical factors, whereas the emission
characteristics at Ennore Creek and Adyar estuary mangroves show anthropogenic influence. Several environmental factors such
as oxygen availability, organic matter, soil physical and chemical properties, in addition to human-mediated interventions
have been identified as influencing emission rates in the mangrove ecosystems. Preliminary CH4 emission estimates for the mangrove ecosystems along the Indian sub- continent and the tropical and subtropical coastline
of the world by linear extrapolation based on surface area range from 0.05 to 0.37 and 2.8 to 19.25 Tg CH4 year−1 respectively. Our results also highlight the impact of human activities on future emission of methane from the mangrove ecosystems.
Received: 3 March 1999 / Accepted: 14 September 1999 相似文献
30.
对某省52家焚烧企业(21家生活垃圾和31家危险废物)排放烟气数据进行了分析,结果表明,两类焚烧企业二噁英类17种单体分布有所不同,生活垃圾焚烧烟气中浓度较高的是O8CDD和O8CDF;危险废物焚烧烟气中较大的是2,3,4,7,8-P5CDF、2,3,7,8-T4CDD和1,2,3,7,8-P5CDD;两类焚烧企业二噁英类单体对I-TEQ贡献最高的都是2,3,4,7,8-P5CDF,贡献率分别为0. 7%~45%和10%~67%;两者的17种二噁英类与I-TEQ的相关性分析表明,1,2,3,7,8-P5CDF在2类焚烧炉中与I-TEQ均存在较高的相关性,其相关系数分别0. 932和0. 927,可以作为潜在的测定指示物。 相似文献