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691.
分析了年产15万t啤酒的生产废水情况,介绍了采用IC厌氧反应器-一体化氧化沟处理该生产废水(7 200 m3/d)的工艺路线和主要设计参数,讨论了废水处理系统的运行情况.其中IC厌氧反应器的HRT为8 h,运行温度为35~37 ℃;一体化氧化沟包括氧化沟段和沉淀池段,总尺寸为40 m×24 m×6 m.IC厌氧反应器COD容积负荷在7.78 kg/(m3·d)时,COD去除率为84%左右.整套废水处理系统的COD总去除率为98%左右,出水COD小于80 mg/L.厌氧所产生的沼气可用于废水的升温. 相似文献
692.
The distribution of trace metals Zn, Ni, Mn, Fe, Cu, Pb, Cd and Cr between suspended particulate matter (SPM) and water in the Conwy estuary, North Wales, has been studied in three surveys in 1998. Dissolved Cu and Mn showed some monthly variations. Most of the dissolved trace metals displayed a negative association with salinity, indicating rivers as a major source of inputs for them. Particulate Zn, Mn and Fe showed a decreasing concentration seaward, whilst the levels of Ni, Cu, Cr and Pb increased with salinity. SPM concentration was the most important variable significantly related to trace metal concentrations in SPM, with an inverse relationship between the two parameters. This was explained by the relative enrichment of trace metals in fine particles at low SPM concentrations and relative depletion of trace metals in coarse particles at high SPM concentrations. Particulate Zn, Mn and Pb were dominated by the fraction available to acetic acid (non-detrital), whilst particulate Ni, Fe and Cr were dominated by the fraction available to nitric acid (detrital). The partition coefficient of trace metals between SPM and water declined with increasing SPM concentration, consistent with the so-called "particle concentration effect". Such a phenomenon may be explained by the presence of fine particles (including colloids) enriched with trace metals at low SPM concentrations, and the salinity-induced desorption. 相似文献
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694.
不同粒度飞灰中16种微量元素的含量分布 总被引:7,自引:0,他引:7
研究了不同粒级的燃煤飞灰中的Ba、Be、Cd、Cr、Cu、Hg、Li、Mn、Ni、Pb、Sr、Ti、V、Zn、Zr元素的含量分布,煤中元素的含量比及富集因子。 相似文献
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The sorption and desorption of Cu and Cd by two species of brown macroalgae and five species of microalgae were studied. The two brown macroalgae, Laminaria japonica and Sargassum kjellmanianum, were found to have high capacities at pHs between 4.0 and 5.0 while for microalgae, optimum pH lay at 6.7. The presence of other cations in solution was found to reduce the sorption of the target cation, suggesting a competition for sorption sites on organisms. Sorption isotherms obeyed the Freundlich equation, suggesting involvement of a multiplicity of mechanisms and sorption sites. For the microalgae tested, Spirulina platensis had the highest capacity for Cd, followed by Nannochloropsis oculata, Phaeodactylum tricornutum, Platymonas cordifolia and Chaetoceros minutissimus. The reversibility of metal sorption by macroalgae was examined and the results show that both HCl and EDTA solutions were very effective in desorbing sorbed metal ions from macroalgae, with up to 99.5% of metals being recovered. The regenerated biomass showed undiminished sorption performance for the two metals studied, suggesting the potential of such material for use in water and wastewater treatment. 相似文献
699.
The estrogenic pollutants 4-tert-octylphenol (OP), 4-nonylphenol (NP) and bisphenol A (BPA) were determined in surface water samples from the Haihe River, Tianjin, China. The analytes were extracted and concentrated from 300 ml acidified water samples by liquid–liquid extractions using dichloromethane, derivatized with trifluoroacetic anhydride, and quantified by gas chromatography–mass spectrometry (GC–MS) with selected ion monitoring (SIM). Among the samples collected from 14 sampling sites, only one sample was found to have a relatively high concentration of BPA (8.30 μg l−1) and NP (0.55 μg l−1). The concentrations of OP, NP and BPA in the other samples were in the range of 18.0–20.2, 106–296 and 19.1–106 ng l−1, respectively. Recoveries for OP, NP and BPA in the spiked water samples were all over 80%. 相似文献
700.
Kang Li Jiazhen Zhou Zhen Mao Ruiwei Xu 《Journal of the Air & Waste Management Association (1995)》2019,69(8):944-955
The obvious disadvantages of biotrickling filters (BTFs) are the long start-up time and low removal efficiency (RE) when treating refractory hydrophobic volatile organic compounds (VOCs), which limits its industrial application. It is worthwhile to investigate how to reduce the start-up period of the BTF for treating hydrophobic VOCs. Here, we present the first study to evaluate the strategy of toluene induction combined with toluene-styrene synchronous acclimatization during start-up in a laboratory-scale BTF inoculated with activated sludge for styrene removal, as well as the effects of styrene inlet concentration (0.279 to 2.659 g·m?3), empty bed residence time (EBRT) (i.e., 136, 90, 68, 45, 34 sec), humidity (7.7% to 88.9%), and pH (i.e., 4, 3, 2.5, 2) on the performance of the BTF system. The experiments were carried out under acidic conditions (pH 4.5) to make fungi dominant in the BTF. The start-up period for styrene in the BTF was shortened to about 28 days. A maximum elimination capacity (ECmax) of 126 g·m?3·hr?1 with an RE of 80% was attained when styrene inlet loading rate (ILR) was below 180 g·m?3·hr?1. The highest styrene RE(s) [of BTF] that could be achieved were 95% and 93.4%, respectively, for humidity of 7.7% and at pH 2. A single dominant fungal strain was isolated and identified as Candida palmioleophila strain MA-M11 based on the 26S ribosomal RNA gene. Overall, the styrene induction with the toluene-styrene synchronous acclimatization could markedly reduce the start-up period and enhance the RE of styrene. The BTF dominated by fungi exhibited good performance under low pH and humidity and great potential in treating styrene with higher inlet concentrations.
Implications: The application of the toluene induction combined with toluene-styrene synchronous acclimatization demonstrated to be a promising approach for the highly efficient removal of styrene. The toluene induction can accelerate biofilm formation, and the adaptability of microorganisms to styrene can be improved rapidly by the toluene-styrene synchronous acclimatization. The integrated application of two technologies can shorten the start-up period of biotrickling filters markedly and promote its industrial application. 相似文献