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411.
提出了一个具有全新运转方式的新型RBC系统-回转升降生物接触工艺。通过清水充氧实验考查了实验装置的充氧能力;通过正交试验,确定了最佳运行条件;在最佳运行条件下,研究了本工艺处理有机废水的性能和效果。 相似文献
412.
Fuhai Geng Qiang Zhang Xuexi Tie Mengyu Huang Xincheng Ma Zhaoze Deng Qiong Yu Jiannong Quan Chunsheng Zhao 《Atmospheric environment (Oxford, England : 1994)》2009,43(3):584-593
In this study, air pollutants, including ozone (O3), nitrogen oxides (NOx = NO + NO2), carbon monoxides (CO), sulfur dioxide (SO2), and volatile organic compounds (VOCs) measured in the Yangtze River Delta (YRD) region during several air flights between September/30 and October/11 are analyzed. This measurement provides horizontal and vertical distributions of air pollutants in the YRD region. The analysis of the result shows that the measured O3 concentrations range from 20 to 60 ppbv. These values are generally below the US national standard (84 ppbv), suggesting that at the present, the O3 pollutions are modest in this region. The NOx concentrations have strong spatial and temporal variations, ranging from 3 to 40 ppbv. The SO2 concentrations also have large spatial and temporal variations, ranging from 1 to 35 ppbv. The high concentrations of CO are measured with small variations, ranging from 3 to 7 ppmv. The concentrations of VOCs are relatively low, with the total VOC concentrations of less than 6 ppbv. The relative small VOC concentrations and the relative large NOx concentrations suggest that the O3 chemical formation is under a strong VOC-limited regime in the YRD region. The measured O3 and NOx concentrations are strongly anti-correlated, indicating that enhancement in NOx concentrations leads to decrease in O3 concentrations. Moreover, the O3 concentrations are more sensitive to NOx concentrations in the rural region than in the city region. The ratios of Δ[O3]/Δ[NOx] are ?2.3 and ?0.25 in the rural and in the city region, respectively. In addition, the measured NOx and SO2 concentrations are strongly correlated, highlighting that the NOx and SO2 are probably originated from same emission sources. Because SO2 emissions are significantly originated from coal burnings, the strong correlation between SO2 and NOx concentrations suggests that the NOx emission sources are mostly from coal burned sources. As a result, the future automobile increases could lead to rapid enhancements in O3 concentrations in the YRD region. 相似文献
413.
Liang Pan Huizheng Che Fuhai Geng Xiangao Xia Yaqiang Wang Chize Zhu Min Chen Wei Gao Jianping Guo 《Atmospheric environment (Oxford, England : 1994)》2010,44(21-22):2587-2596
The characteristics of Aerosol Optical Depth (AOD) and Angstrom exponent were analyzed and compared using Cimel sunphotometer data from 2007 to 2008 at five sites located in the Yangtze River Delta region of China. The simultaneous measurements between Lin’an and ZFU showed a very high consistency of AOD at all wavelengths. The differences are less than 0.02 for Angstrom exponent and AOD at all wavelengths. The mean values of AOD at 440 nm at the Pudong, Taihu and Lin’an were about 0.74 ± 0.43, 0.85 ± 0.46, and 0.89 ± 0.46, respectively. The mean values of Angstrom exponents were about 1.27 ± 0.30, 1.20 ± 0.28 and 1.32 ± 0.35, respectively. The variation of monthly averaged AOD over Pudong showed a single peak distribution, with the maximum value occurring in July (AOD440nm 1.26 ± 0.61) and minimum in January (AOD440nm 0.50 ± 0.27). However, the variations of monthly averaged AOD at Taihu and Lin’an showed a bi-modal distribution. There were peak values of AOD occurring in July (AOD440nm 1.41 ± 0.49) and September (AOD440nm 1.22 ± 0.52) for Taihu. For Lin’an, the two peak values of AOD occurred in June (AOD440nm 1.17 ± 0.69) and September (AOD440nm 1.28 ± 0.46). The AOD accumulated mainly between 0.30–0.90(68%), 0.30–1.20(75%) and 0.30–1.20 (~75%) at Pudong, Taihu, and Lin’an, respectively. The Angstrom exponent accumulated mainly between 1.10–1.60 (75%), 1.10–1.50 (63%) and 1.20–1.60, 50% (50%) at Pudong, Taihu, and Lin’an, respectively.The synchronized observation showed that the AOD at Pudong was larger than those at Dongtan by 0.03, 0.03, 0.04, 0.07, and 0.08 at wavelengths of 1020 nm, 870 nm, 670 nm, 500 nm and 440 nm, respectively. The synchronized observations at Pudong, Taihu and Lin’an showed that the three stations had high level AOD with means at 440 nm about 0.68, 0.73, and 0.78, respectively. The relationship between MODIS retrieved and ground-based measured AOD shows good agreement with R2 ranging from 0.68 to 0.79 at Pudong, Taihu, Lin’an and Dongtan. The MODIS results were overestimated comparing the ground measurements at Pudong, Taihu, and Dongtan but exceptional at Lin’an.The analysis results between aerosol optical properties and wind measurement at Pudong showed that the wind speed from the east correlates with the lower observed AOD. The back trajectory analysis indicates that more than 50% airmasses were from the marine area at Pudong, while back trajectories distribution is relatively homogeneous at Lin’an. 相似文献
414.
Planning for integrated solid waste management at the industrial park level: a case of Tianjin, China 总被引:1,自引:0,他引:1
Industrial parks play a significant role in the production and use of goods and services. The proper management of solid waste is a major challenge for industrial parks due to the large quantity of wastes and the variability of waste characteristics from these types of developments. Therefore, integrated solid waste management has become very crucial to the industrial park managers. Such an approach requires industrial park managers to assess the overall use of resources, and to seek waste reduction, reuse and recycling opportunities both at the individual company level and among different tenant companies. The adoption of this method can bring both economic and environmental benefits. This paper introduces the planning efforts of a real case in China. It first presents the basic information on Tianjin Economic Development Area (TEDA), and then introduces its current practices on solid waste management. The main focus of this paper is to describe how to plan an integrated solid waste management system at TEDA. Benefits and challenges are all identified and analyzed. The experiences and methods from this case study should be applied in other industrial parks so as to improve the overall eco-efficiency of the whole industrial park. 相似文献
415.
Song P Geng FH Sang XF Chan CY Chan LY Yu Q 《Environmental monitoring and assessment》2012,184(10):5957-5970
The characteristics and sources of major hydrocarbons and halocarbons in the wintertime ambient air of urban center of Shanghai, a mega city of China, were investigated. Propane, toluene, ethyl acetate, and benzene were the most abundant hydrocarbons. The majority of species showed significant variability in mixing ratios with occasional episodic increases. The more common use of liquefied petroleum gas fuel for taxis and light motorcycles was believed to lead to high levels of ambient propane over the urban center of Shanghai. Correlating with toluene, dichloromethane, and 1,2-dichloroethane (1,2-DCE), abundant chloromethane (up to a daily mean of 1.61?±?0.99 ppbv and a maximum of 5.34 ppbv) was mainly associated with industrial emissions, although biomass burnings exist widely in east China. The Chinese New Year (CNY) holiday period with no industrial activity over China provides a platform for the study of industrial emissions over the urban atmosphere of Shanghai. The normal weekly cycles were characterized by higher and more variable mixing ratios during weekdays which dropped during weekends. Enhanced mixing ratios were observed in the fortnight before the CNY holidays due to increased industrial emissions as a result of overtime production to make up for the holiday losses. During the CNY holidays, lower level and less variable mixing ratios were observed. A benzene/toluene (B/T) ratio of 0.6?±?0.4 (mean?±?std.) for the morning rush hour samples was identified to be the characteristic ratio of vehicular emissions. However, a B/T ratio of 0.4?±?0.2 from vehicles and other sources was derived for the ambient air. 相似文献
416.
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
417.
Jia Wang Ning Bo Geng Yi Fei Xu Wen Ding Zhang Xiao Yan Tang Rui Qin Zhang 《Environmental monitoring and assessment》2014,186(11):7461-7473
Ambient air samples were collected at two different locations between 2011 and 2012 in Zhengzhou, China in order to assess the concentration level, health risks, as well as the sources of polycyclic aromatic hydrocarbons (PAHs) in particulate matter (PM2.5). The mean annual levels of PM2.5 observed at industry site and residential site were 172?±?121 and 160?±?72 μg m?3, respectively, which were about five times the annual value of proposed PM2.5 standard (35 μg m?3) in China. The PM2.5 in all daily samples (n?=?47) exceeds the proposed PM2.5 standard in China (75 μg m?3) at both industrial and residential sites. Seasonal variations of PM2.5 showed a clear trend of winter?>?autumn?>?spring?>?summer at both sites. The total concentrations of 16 PM2.5-associated PAHs ranged from 61?±?51 to 431?±?281 and 38?±?25 to 254?±?189 ng m?3, with mean value of 176?±?233 and 111?±?146 ng m?3 at industry and residential sites, respectively. The major species were fluoranthene, pyrene, chrysene, benzo[b]fluoranthene and benzo[k]fluoranthene, and the concentration levels of PAHs in PM2.5 were higher in winter than those of other seasons at both sites. The annual mean values of toxicity equivalency concentrations of ∑16PAHs in PM2.5 were 22.8 and 13.5 ng m?3 in industry and residential area, respectively. In this study, the risk level of adult citizens through inhalation exposure to PAHs was calculated. The average estimates of lifetime inhalation cancer risks were approximately 8.9?×?10?7 and 6.3?×?10?7 for industry and residential sites, respectively. The main sources of 16 PAHs from both diagnostic ratios and principle component analysis identified as vehicular emissions and coal combustion. 相似文献
418.
选取2家燃煤电厂3台循环流化床机组进行现场监测,在不同负荷条件下,采集并分析燃煤、烟气、飞灰、炉渣等样品的Pb含量,通过物料平衡核算,对循环流化床机组各环节Pb的迁移特性进行研究。结果表明:机组负荷变化对烟气、飞灰、炉渣的Pb含量影响不大,烟气Pb排放质量浓度均在2μg/m~3以下。电袋复合除尘处理后,烟气中颗粒态Pb的浓度总体低于气(溶胶)态Pb的浓度。Pb在炉渣和飞灰中均有富集,平均富集因子分别为2.16和3.02。飞灰较炉渣对Pb具有更强的富集能力,布袋灰中Pb含量略高于电除尘灰。循环流化床锅炉燃烧后Pb分布在飞灰、炉渣和外排烟气中的比例分别为62.49%、37.49%和0.02%,Pb释放率低于煤粉炉,在Pb污染控制方面更具优势。除尘过程对烟气中Pb的影响主要表现为飞灰对Pb的吸附和除尘器对飞灰的分离脱除,尤以后者为主。由于烟气中气(溶胶)态Pb所占的比例很低,Pb基本吸附在飞灰上,除尘效率的高低直接决定了Pb的去除效果。 相似文献
419.
420.
耿世刚 《中国环境管理干部学院学报》2012,(5):72-74,87
立足当前环境类高等职业教育人才培养中存在的突出问题,以"以人为本"、"需求导向"、"特色品牌"、"工学结合"为原则,提出了环境类高职院校应在构建人才培养"三个平台、四个模块"的基础上,突出实践能力培养,实施工学结合的人才培养模式。 相似文献