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51.
高浓度印染废水处理工程工艺条件与实例分析 总被引:8,自引:0,他引:8
研究以三相生物流化床作为工程化反应器处理印染废水的工程工艺条件及操作特性,分别测定流化床内的气相含率,兴体循环速度及体积氧传质系数。 相似文献
52.
谢长旺 《防灾科技学院学报》2005,7(1):85-87
建设高校校园文化是发挥高校育人作用的重要工作,对全面推进素质教育和引导学生的全面发展都起着重要作用.本文就高校校园文化的概念、高校校园文化的作用、高校校园文化的建设要求与方法进行了论述,并提出了个人见解. 相似文献
53.
Yanke Yu Jinxiu Wang Jinsheng Chen Xinjiang He Yujing Wang Kai Song Zongli Xie 《环境科学学报(英文版)》2016,28(9):100-108
The regeneration of commercial SCR(Selective Catalyst Reduction) catalysts deactivated by Pb and other elements was studied.The deactivated catalyst samples were prepared by chemical impregnation with mixed solution containing K_2SO_4,Na_2SO_4,CaSO_4,Pb(NO_3)_2and NH_4H_2PO_4.A novel method combining Ethylenediaminetetraacetic acid disodium salt(EDTA-2Na) and H_2SO_4solution(viz.catalysts treated by dilute EDTA-2Na and H_2SO_4 solution in sequence) was used to recover the activity of deactivated samples,and the effect was compared with single H_2SO_4,oxalic acid,acetic acid,EDTA or HNO_3 solutions.The surface structure,acidity and reducibility of samples were characterized by N_2adsorption–desorption,inductively coupled plasma optical emission spectrometer(ICP-OES),scanning electron microscopy(SEM),X-ray diffraction(XRD),X-ray fluorescence(XRF),H-2-temperature programmed section(H_2-TPR),NH3-temperature programmed desorption(NH3-TPD) and in situ DRIFTS.Impurities caused a decrease of specific surface area and surface reducibility,as well as Br?nsted acid sites,and therefore led to severe deactivation of the SCR catalyst.The use of an acid solution alone possibly eliminated the impurities on the deactivated catalyst to some extent,and also increased the specific surface area and Br?nsted acid sites and promoted the surface reducibility,thus recovered the activity partially.The combination of EDTA-2Na and H_2SO_4 could remove most of the impurities and improve the activity significantly.The removal of Pb should be an important factor for regeneration.Due to a high removal rate for Pb and other impurities,the combination of EDTA-2Na and H_2SO_4 solutions provided the best efficiency. 相似文献
54.
Estimating emissions from crop residue open burning in China based on statistics and MODIS fire products 总被引:1,自引:0,他引:1
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
55.
A novel technology of two-step fast microwave-assisted pyrolysis(f MAP) of corn stover for bio-oil production was investigated in the presence of microwave absorbent(Si C) and HZSM-5catalyst. Effects of f MAP temperature and catalyst-to-biomass ratio on bio-oil yield and chemical components were examined. The results showed that this technology, employing microwave, microwave absorbent and HZSM-5 catalyst, was effective and promising for biomass fast pyrolysis. The f MAP temperature of 500°C was considered the optimum condition for maximum yield and best quality of bio-oil. Besides, the bio-oil yield decreased linearly and the chemical components in bio-oil were improved sequentially with the increase of catalyst-to-biomass ratio from 1:100 to 1:20. The elemental compositions of bio-char were also determined. Additionally, compared to one-step f MAP process, two-step f MAP could promote the bio-oil quality with a smaller catalyst-to-biomass ratio. 相似文献
56.
57.
采用溶胶-凝胶法和浸渍法制备了Pd/CeZr/TiO2Al2O3蜂窝状金属丝网催化剂,并将其应用于在富氧条件下以丙烯选择催化还原NOx的研究.利用扫描电镜(SEM)分析了钛酸四丁酯的含量以及涂敷次数对TiO2涂层的影响,系统地考察了Pd含量、氧气浓度和空速对蜂窝状金属丝网催化剂催化性能的影响.实验结果表明,采用钛酸四丁酯的含量为20.0%的溶胶,涂敷2次,可以在金属丝网载体上氧化铝涂层表面获得均匀、无皲裂的TiO2涂层;Pd含量在0.23%~1.06%的范围内, NOx的转化率随Pd含量的增加而减小, Pd含量为0.23%时, NOx表现最高的NOx转化率;反应气体中氧气浓度从1.5%增加到6.0%, NOx的转化率随氧气浓度的增加而增大,当氧气浓度高于6.0%, NOx的转化率则随氧气浓度的增加而迅速减小; NOx的转化率随着空速的增加而降低,在高温条件下空速对转化率的影响要大于在低温条件下. 相似文献
58.
徐闻珊瑚礁保护区海水中多环芳烃的初探 总被引:2,自引:0,他引:2
2006年8月,对徐闻珊瑚礁自然保护区中多环芳烃的污染现状进行调查和研究,采用固相萃取,GC-MS检测,分析其中16种多环芳烃(PAHs)单体的含量,结果表明该海域海水中16种PAHs的总平均含量为87.06±90.62 ng·L^-1,变化范围为43.31~435.64 ng·L^-1,与世界其它一些近岸海区海水中的PAHs含量相比污染较为严重。A1站位的PAHs含量偏高,主要来源于陆地的工业废水和生活污水以及渔船油污。PAHs含量的增多对珊瑚礁生态系统具有一定影响,最终将影响到人类的自身健康。 相似文献
59.
CO2是《京都议定书》要求减排的6种温室气体之一,《京都议定书》还确立了有助于发展中国家获得资金和先进技术的清洁发展机制(CDM)。本文结合实际工程案例,介绍了合成氨副产CO2气的回收和利用方法,为我国氮肥行业申请CDM项目资助,回收利用CO2,减少CO2排放提供技术参考。 相似文献
60.