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101.
接种不同污泥启动厌氧氨氧化ASBR反应器研究 总被引:7,自引:0,他引:7
采用ASBR反应器,分别以好氧硝化污泥和厌氧颗粒污泥为种泥,通过对氨氮、亚硝酸盐氮等指标的监测和数据分析、污泥颜色的观察,研究2个厌氧氨氧化反应器启动的可行性及其差异.结果表明,2个厌氧氨氧化反应器均可成功启动;采用好氧硝化污泥启动厌氧氨氧化反应器耗时142 d,启动前后污泥颜色变化不大,亚硝酸盐氮浓度超过20 mmol/L会对厌氧氨氧化产生明显的抑制作用;采用厌氧颗粒污泥启动厌氧氨氧化反应器耗时249 d,启动前后污泥颜色变化很大,从黑色逐渐变为砖红色,亚硝酸盐氮浓度超过13.4 mmol/L会对厌氧氨氧化产生抑制作用;分别用以上2种污泥启动的厌氧氨氧化ASBR反应器中占优势地位的厌氧氨氧化菌不同. 相似文献
102.
103.
强化一级处理与SBR工艺处理油脂精炼加工废水 总被引:1,自引:0,他引:1
介绍了规模为200 m^3/d的油脂精炼加工废水处理工程的设计与运行.先经强化一级处理工艺预处理,再经SBR工艺处理,出水的有关指标能达到设计的排放标准,工艺运行稳定. 相似文献
104.
Zhang C Wang L Wu F Deng N 《Environmental science and pollution research international》2006,13(3):156-160
Background For their high photoreactivity, Fe(III)-carboxylate complexes are important sources of H2O2 for some atmospheric and surface
waters. Citrate is one kind of carboxylate, which can form complexes with Fe(III). In our previous study, we have applied
Fe(III)-citrate complexes to degrade and decolorize dyes in aqueous solutions both under UV light and sunlight. Results have
shown that carboxylic acids can promote the photodegradation efficiency. It is indicated that the photolysis of Fe(III)-citrate
complexes may cause the formation of some reactive species (e. g. H2O2 and ·OH). This work is attempted to quantify hydroxyl
radicals generated in the aqueous solution containing Fe(III)-citrate complexes and to interpret the photoreactivity of Fe(III)-citrate
complexes for degrading organic compounds.
Methods By using benzene as the scavenger to produce phenol, the photogeneration of ·OH in the aqueous solution containing Fe (III)-citrate
complexes was determined by HPLC.
Results and Discussion In the aqueous solution containing 60.0/30.0 mM Fe(III)/citrate and 7.0 mM benzene at pH 3.0, 96.66 mM ·OH was produced after
irradiation by a 250W metal halide light (l ≥ 313 nm) for 160 minutes. Effects of initial pH value and concentrations of Fe(III)
and citrate on ·OH radical generation were all examined. The results show that the greatest photoproduction of ·OH in the
aqueous solution (pH ranged from 3.0 to 7.0) was at pH 3.0. The photoproduction of ·OH increased with increasing Fe(III) or
citrate concentrations.
Conclusion In the aqueous solutions containing Fe(III)-citrate complexes, ·OH radicals were produced after irradiation by a 250W metal
halide light. It can be concluded that Fe(III)-citrate complexes are important sources of ·OH radicals for some atmospheric
and surface waters.
Recommendations and Outlook It is believed that the photolysis of Fe(III)-citrate complexes in the presence of oxygen play an important role in producing
·OH both in atmospheric waters and surface water where high concentrations of ferric ions and citrate ions exist. The photoproduction
of ·OH has a high oxidizing potential for the degradation of a wide variety of natural and anthropogenic organic and inorganic
substances. We can use this method for toxic organic pollutants such as organic dyes and pesticides. 相似文献
105.
Effect of arsenic on chloroplast ultrastructure and calcium distribution in arsenic hyperaccumulator Pteris vittata L 总被引:2,自引:0,他引:2
This study investigated the impacts of arsenic (As) on the chloroplast ultrastructure and calcium (Ca) distribution in Chinese brake (Pteris vittata L.) mainly by histochemical methods, with an emphasis on the possible function of Ca in As detoxification and accumulation in P. vittata. P. vittata was grown in an artificially contaminated soil added with different concentrations of Na(2)HAsO(4) (0, 100, 300 and 800 mg kg(-1) As dry soil) for 24 weeks in a greenhouse. The addition of As did not affect the chloroplast ultrastructure of young pinna, meanwhile most of the membrane systems of chloroplasts in mature pinna were severely damaged under high As condition. Calcium concentration in the fronds of P. vittata was not significantly affected by the addition of As, but Ca concentration in the mature pinna significantly increased by As addition, consistent with the position appearing As toxicity. When no As was added, most of calcium precipitates distributed around the inner membrane of vacuole. But when the pinna appeared plasmolysis, more calcium precipitates resided outside the cell membrane and bigger particles evenly distributed in the cytoplasm. All the results indicated that Ca had a close relation with As toxicity in P. vittata. 相似文献
106.
107.
Fu Li Chen Yi Yang Xinyi Yang Zuyao Liu Sha Pei Lei Feng Baixiang Cao Ganxiang Liu Xin Lin Hualiang Li Xing Ye Yufeng Zhang Bo Sun Jiufeng Xu Xiaojun Liu Tao Ma Wenjun 《Environmental science and pollution research international》2019,26(20):20137-20147
Environmental Science and Pollution Research - Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air... 相似文献
108.
为研究管道内金属丝网对甲烷/空气预混火焰传播的影响,通过实验和三维数值模拟研究安装金属丝网的管道内火焰传播特性以及流场、温度场的变化。结果表明:40目4层的金属丝网可以使火焰淬熄,30目4层的金属丝网无法淬熄,但可以使火焰停滞3 ms;大涡模型可以很好地对管道内火焰淬熄现象进行模拟;当火焰穿过30目4层金属丝网时,速度增大,在Kelvin Helmholtz不稳定和Rayleigh Taylor不稳定的耦合作用下形成湍流;金属丝网的目数会影响热量在丝网层中的扩散,当金属丝网为30目4层时,火焰热量扩散快,而当金属丝网为40目4层时,火焰热量扩散慢且温度大幅度衰减,衰减率达到83%。 相似文献
109.
重大危险源动态监管与应急救援平台建设研究 总被引:4,自引:9,他引:4
由于缺乏相关的国家及行业标准规范,各地重大危险源监管与应急救援平台建设中主要存在如下问题:其一,只重视硬件建设,而忽视软件和信息建设;其二,重大危险源安全监管数据采集标准不统一,采用的相关软件和硬件技术不规范,难以在各级平台间实现数据共享。笔者参照重大危险源4级监管与应急救援体系,将国家科技攻关课题的相关研究成果同安全生产工作的实际需要有机地结合,提出重大危险源动态监管和事故应急救援平台建设方案。分析我国重大危险源监管及应急救援系统的建设现状及存在的主要问题;提出平台的设计原则、实现数据共享的主要思路;设计软件系统总体规划及各部分的功能。 相似文献
110.
Zhiqiang Zhai Hongyu Lu Weinan He Lei Yu 《Journal of the Air & Waste Management Association (1995)》2017,67(9):949-957
Vehicle-specific power (VSP) has been found to be highly correlated with vehicle emissions. It is used in many studies on emission modeling such as the MOVES (Motor Vehicle Emissions Simulator) model. The existing studies develop specific VSP distributions (or OpMode distribution in MOVES) for different road types and various average speeds to represent the vehicle operating modes on road. However, it is still not clear if the facility- and speed-specific VSP distributions are consistent temporally and spatially. For instance, is it necessary to update periodically the database of the VSP distributions in the emission model? Are the VSP distributions developed in the city central business district (CBD) area applicable to its suburb area? In this context, this study examined the temporal and spatial consistency of the facility- and speed-specific VSP distributions in Beijing. The VSP distributions in different years and in different areas are developed, based on real-world vehicle activity data. The root mean square error (RMSE) is employed to quantify the difference between the VSP distributions. The maximum differences of the VSP distributions between different years and between different areas are approximately 20% of that between different road types. The analysis of the carbon dioxide (CO2) emission factor indicates that the temporal and spatial differences of the VSP distributions have no significant impact on vehicle emission estimation, with relative error of less than 3%.Implications: The temporal and spatial differences have no significant impact on the development of the facility- and speed-specific VSP distributions for the vehicle emission estimation. The database of the specific VSP distributions in the VSP-based emission models can maintain in terms of time. Thus, it is unnecessary to update the database regularly, and it is reliable to use the history vehicle activity data to forecast the emissions in the future. In one city, the areas with less data can still develop accurate VSP distributions based on better data from other areas. 相似文献