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81.
污染源在线监测系统(CEMS)的验收比对监测   总被引:2,自引:1,他引:1  
随着节能减排的开展,各重点污染源企业,特别是SO2等标排放负荷较大的热电、钢铁等使用燃煤锅炉的企业,都按照环保局的要求安装了污染源在线监测系统CEMS。CEMS数据的可靠性、正确性、稳定性对于污染减排有着决定性作用,CEMS已成为一种最有效的定量和监控管理手段。本文介绍了CEMS系统的组成及功能,以及验收监测比对法规依据,并根据《固定污染源烟气排放连续监测技术规范》(HJ/T75—2007)(试行)和《固定污染源烟气排放连续监测系统技术要求及检测方法》(HJ/T75—2007)(试行)验收监测比对指标,简要说明了验收比对的方法并分析了在实际监测中遇到的问题,提出了需要注意的事项。  相似文献   
82.
天津港运输船舶大气污染物排放清单   总被引:7,自引:0,他引:7  
运输船舶产生的大气污染物对港口大气环境有重要影响,但我国对这部分内容的研究却相当薄弱.本文首先对天津港运输船舶的总体情况进行调研,根据其排放控制技术水平合理选择了排放因子;而后采用基于燃料消耗的方法,对2006年天津港运输船舶排放的NOx、HC、CO和PM_(10)进行了计算,建立了天津港运输船舶大气污染物的排放清单;最后对2010年和2020年天津港的运输船舶大气污染排放情况进行了预测.该清单的估算和预测可以为加强排放控制和制定相关法规提供重要依据.  相似文献   
83.
A laboratory study was conducted to investigate volatile organic compound(VOC) emissions from agricultural soil amended with wheat straw and their associations with bacterial communities for a period of 66 days under non-flooded and flooded conditions. The results indicated that ethene, propene, ethanol, i-propanol, 2-butanol, acetaldehyde, acetone,2-butanone, 2-pentanone and acetophenone were the 10 most abundant VOCs, making up over 90% of the total VOCs released under the two water conditions. The mean emission of total VOCs from the amended soils under the non-flooded condition(5924 ng C/(kg·hr)) was significantly higher than that under the flooded condition(2211 ng C/(kg·hr)). One "peak emission window" appeared at days 0–44 or 4–44, and over 95% of the VOC emissions occurred during the first month under the two water conditions. Bacterial community analysis using denaturing gradient gel electrophoresis(DGGE) showed that a relative increase of Actinobacteria, Bacteroidetes, Firmicutes and γ-Proteobacteria but a relative decrease of Acidobacteria with time were observed after straw amendments under the two water conditions. Cluster analysis revealed that the soil bacterial communities changed greatly with incubation time, which was in line with the variation of the VOC emissions over the experimental period. Most of the above top 10 VOCs correlated positively with the predominant bacterial species of Bacteroidetes, Firmicutes and Verrucomicrobia but correlated negatively with the dominant bacterial species of Actinobacteria under the two water conditions. These results suggested that bacterial communities might play an important role in VOC emissions from straw-amended agricultural soils.  相似文献   
84.
海南岛近岸海域环境容量与纳污总量分析   总被引:1,自引:0,他引:1  
通过对海南岛"十二五"期间近岸海域纳污总量、环境质量状况及环境容量比较分析,得出各主要排污区环境容量的剩余环境容量。结果表明,全省主要污染物化学需氧量入海量仅占环境容量的2.6%,氨氮占环境容量的26.6%,虽然全省近岸海域环境基本未受污染物入海量影响,仍有较大的纳污空间,可利用的环境容量非常充裕。为避免出现排污达标但环境质量下降的状况,提出建立近岸海域主要污染物总量控制制度,由浓度控制到总量和浓度控制并存。  相似文献   
85.
山东省汽车喷涂行业VOCs排放特征研究   总被引:3,自引:1,他引:2  
采用气袋采样-气相色谱/质谱法,采集并分析了山东省内小型通用车、货车、电动商务车以及半挂车4类典型汽车喷涂企业挥发性有机物(VOCs)的排放特征。结果表明:山东省汽车喷涂企业中VOCs排放总量以及检出数量排序为:半挂车喷涂企业电动商务车喷涂企业货车喷涂企业小型通用车喷涂企业。各类汽车喷涂企业喷漆以及烘干车间排放的VOCs大多以苯类物质为主(小型通用车面漆烘干车间除外),在小型通用车以及半挂车涂装企业废气中烷烃类物质占比较大。不同企业以及各企业不同工序之间特征VOCs排放浓度有较大差别,喷漆车间特征VOCs浓度要远高于烘干车间。  相似文献   
86.
With the objective of reducing the large uncertainties in the estimations of emissions from crop residue open burning, an improved method for establishing emission inventories of crop residue open burning at a high spatial resolution of 0.25°× 0.25° and a temporal resolution of1 month was established based on the moderate resolution imaging spectroradiometer(MODIS) Thermal Anomalies/Fire Daily Level3 Global Product(MOD/MYD14A1). Agriculture mechanization ratios and regional crop-specific grain-to-straw ratios were introduced to improve the accuracy of related activity data. Locally observed emission factors were used to calculate the primary pollutant emissions. MODIS satellite data were modified by combining them with county-level agricultural statistical data, which reduced the influence of missing fire counts caused by their small size and cloud cover. The annual emissions of CO_2, CO, CH_4,nonmethane volatile organic compounds(NMVOCs), N_2O, NO_x, NH_3, SO_2, fine particles(PM2.5),organic carbon(OC), and black carbon(BC) were 150.40, 6.70, 0.51, 0.88, 0.01, 0.13, 0.07, 0.43,1.09, 0.34, and 0.06 Tg, respectively, in 2012. Crop residue open burning emissions displayed typical seasonal and spatial variation. The highest emission regions were the Yellow-Huai River and Yangtse-Huai River areas, and the monthly emissions were highest in June(37%).Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of within ±126% for N_2O to a high of within ± 169% for NH_3.  相似文献   
87.
This article compiles the actual knowledge of the biogenic volatile organic compound (BVOC) emissions estimated using model methods in the Pearl River Delta (PRD) region, one of the most developed regions in China. The developed history of BVOC emission models is presented briefly and three typical emission models are introduced and compared. The results from local studies related to BVOC emissions have been summarized. Based on this analysis, it is recommended that local researchers conduct BVOC emission studies systematically, from the assessment of model inputs, to compiling regional emission inventories to quantifying the uncertainties and evaluating the model results. Beyond that, more basic researches should be conducted in the future to close the gaps in knowledge on BVOC emission mechanisms, to develop the emission models and to refine the inventory results. This paper can provide a perspective on these aspects in the broad field of research associated with BVOC emissions in the PRD region.  相似文献   
88.
对一放置2年时间的储罐试验模型进行长周期的声发射腐蚀监测,通过研究其在稳定腐蚀状态下的声发射信号特征,分析其腐蚀的机理和信号产生的原因,形成对储罐腐蚀更深入的认识。文章还对稳定腐蚀状态下的储罐声发射特征参数进行统计分析,为后续的储罐在线声发射检测评价打下数据基础。  相似文献   
89.
We examine the choice of policy instruments (price, quantity or a mix of the two) when two pollutants are regulated and firms' abatement costs are private information. Whether abatement efforts are complements or substitutes is key determining the choice of policies. When pollutants are complements, a mixed policy instrument with a tax on one pollutant and a quota on another is sometimes preferable even if the pollutants are identical in terms of benefits and costs of abatement. Yet, if they are substitutes, the mixed policy is dominated by taxes or quotas.  相似文献   
90.
Although it has long been recognized that significant amounts of nitrogen, typically in the form of ammonia (NH(3)) applied as fertilizer, are lost to the atmosphere, accurate estimates are lacking for many locations. In this study, a detailed, bottom-up method for estimating NH(3) emissions from synthetic fertilizers in China was used. The total amount emitted in 2005 in China was estimated to be 3.55 Tg NH(3)-N, with an uncertainty of ± 50%. This estimate was considerably lower than previously published values. Emissions from urea and ammonium bicarbonate accounted for 64.3% and 26.5%, respectively, of the 2005 total. The NH(3) emission inventory incorporated 2448 county-level data points, categorized on a monthly basis, and was developed with more accurate activity levels and emission factors than had been used in previous assessments. There was considerable variability in the emissions within a province. The NH(3) emissions generally peaked in the spring and summer, accounting for 30.1% and 48.8%, respectively, of total emissions in 2005. The peaks correlated with crop planting and fertilization schedules. The NH(3) regional distribution pattern showed strong correspondence with planting techniques and local arable land areas. The regions with the highest atmospheric losses are located in eastern China, especially the North China Plain and the Taihu region.  相似文献   
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