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411.
We investigated the correlation between performance and the bacteria community composition by H2S and toluene co-treatment.
Operation of the bioreactor was divided into four stages, in which the inlet concentration of toluene and H2S were gradually increased.
In Stage I, toluene was the sole target compound with an average removal e ciency of 86.49%. After adding H2S in Stage II, removal
e ciency of toluene decreased immediately and recovered gradually to 85.96%. When the inlet concentration of toluene and H2S
was increased in Stage III and Stage IV, respectively, the average removal e ciency for toluene increased continuously from 86.31%
to 87.24%. The elimination capacities of toluene increased with increasing inlet loading rates of toluene and H2S. Results of the
PCR-DGGE analysis showed a turnover growth and decline of the microbial populations in the bioreactor. In Stage I, the dominant
toluene-degrading bacteria mainly contained Pseudomonas sp. strain PS+ and Hydrogenophaga sp. In Stage IV, however, the dominant
toluene-degrading bacteria was aciduric bacteria (Clostridium populeti). The dominant microbial community in the bioreactor enhanced
the elimination capacity of toluene, and adding H2S changed the environment of microbial growth, thus resulted in an evolution of
dominant microorganisms. Analyses of microbial community and their activities provides valuable information to e ciently enhance
simultaneous removal of toluene and H2S in the bioreactor. 相似文献
412.
A kinetic model for the Ti(IV)-catalyzed H2O2/O3 process was established, and the experimental results demonstrated that the model could well describe this ozone-based oxidative system mathematically and chemically. 相似文献
413.
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415.
基于氢夹点理论和超结构理论,提出一套考虑燃料气价值的氢气网络优化计算方法,计算结果更加合理、经济、实用。运用此方法,不仅能定量评估某个加氢装置操作方式的合理性,而且能根据炼厂的氢气网络计算提出合理的优化运行方案。 相似文献
416.
曝气充氧对污水中硫化物去除效果的研究 总被引:1,自引:0,他引:1
为了降低污水中高浓度硫化物对构筑物的腐蚀以及人体的危害,在预处理设施沉砂池中进行曝气充氧试验,研究了不同的曝气量(3 m3/h、4 m3/h、6 m3/h、8 m3/h)和不同的水力停留时间(10 min、20 min、30 min)对污水中硫化物去除效果的影响,并探讨硫化物的氧化效果。试验结果表明:反应器出水中的硫化物浓度随着曝气量、水力停留时间的增大而降低;硫化物的氧化效果随着曝气量的增加,呈先减小后增大的趋势。在最佳曝气量4 m3/h、停留时间30 min时,硫化物平均去除率为94.6%,平均氧化率为83.8%。 相似文献
417.
418.
A fibrous strong base anion exchanger (QAPPS) was prepared for the first time via chloromethylation and quaternary amination reaction of polyphenylene sulfide fiber (PPS), and its physical-chemical structure and adsorption behavior for Cr(VI) were characterized by FT-IR, Energy Dispersive Spectrometry, TG-DTG, elemental analysis and batch adsorptive technique, respectively. The novel fibrous adsorbent could effectively adsorb Cr(VI) over the pH range 1-12, the maximum adsorption capacity was 166.39 mg/g at pH 3.5, and the adsorption behavior could be described well by Langmuir isotherm equation model. The adsorption kinetics was studied using pseudo first-order and pseudo second-order models, and the t1/2 and equilibrium adsorption time were 5 and 20 min respectively when initial Cr(VI) concentration was 100 mg/L. The saturated fibers could be regenerated rapidly by a mixed solution of 0.5 mol/L NaOH and 0.5 mol/L NaCl, and the adsorption capacity was well maintained after six adsorption-desorption cycles. 相似文献
419.
420.
外源含硫化合物对土壤挥发性有机硫化合物交换通量的影响 总被引:1,自引:0,他引:1
通过静态箱采样和Entech7100预浓缩仪-GC-MS分析了半胱氨酸、硫化钠和硫酸钠对土壤吸收或释放羰基硫(COS)、二甲基硫醚(DMS)、二硫化碳(CS2)和二甲二硫醚(DMDS)等4种挥发性有机硫化合物(VOSCs)的影响.结果表明,添加半胱氨酸后,土壤由COS和CS2汇转变为源,DMS和DMDS通量显著增加,且... 相似文献