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921.
On the basis of continuous tests and batch tests, conversion regular patterns of acetate, propionate and butyrate in activated sludge at different heights of the UASB reactor were conducted. Results indicated that the conversion capacity of the microbe is decided by the substrate characteristic when sole VFA is used as the only substrate. But when mixed substrates are used, the conversion regulations would have changed accordingly.Relationships of different substrates vary according to their locations. In the whole reactor, propionate‘s conversion is restrained by acetate and butyrate of high concentration. On the top and at the bottom of the reactor, conversion of acetate, but butyrate, is restrained by propionate. And in the midst, acetate‘s conversion is accelerated by propionate while that of butyrate is restrained. It is proved, based on the analysis of specific conversion rate, that the space distribution of the microbe is the main factor that affects substrates‘ conversion. The ethanol-type fermentation of the acidogenicophase is the optimal acid-type fermentation for the two-phase anaerobic process. 相似文献
922.
Bioreactor landfills allow a more active landfill management that recognizes the biological, chemical and physical processes involved in a landfill environment. The laboratory-scale simulators of landfill reactors treating municipal solid wastes were studied, the effect of solid waste size, leachate recirculation, nutrient balance, pH value, moisture content and temperature on the rate of municipal solid waste (MSW) biodegradation were determined, and it indicated the optimum pH value, moisture content and temperature decomposing MSW. The results of waste biodegradation were compared with that of the leachate-recirculated landfill simulator and conservative sanitary landfill simulator. In the control experiment the antitheses of a decreasing trend of the organic load, measured as biological oxygen demand and chemical oxygen demand, was shown. An obvious enhancement of effective disposal from conservative sanitary landfill (CSL) simulator, to the leachate-recirculated landfill (LRL) simulator and to the conditioned bioreactor landfill(CBL) simulator would be noted, through displaying the compared results of solid waste settlement, heavy, metal concentration in leachate, methane production rate, biogas composition, BOD and COD as well as their ratio. 相似文献
923.
Aerobic heterotrophic granular sludge was cultivated in a sequencing batch shaking reactor(SBSR) in which a synthetic wastewater containing glucose as carbon source was fed. The characteristics of the aerobic granules were investigated. Compared with the conventional activated sludge flocs, the aerobic granules exhibit excellent physical characteristics in terms of settleability, size, shape, biomass density, and physical strength.Scanning electron micrographs revealed that in mature granules little filamentous bacteria could be found, rod-shaded and coccoid bacteria were the dominant microorqanisms. 相似文献
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用活性炭粒子群电催化反应器处理氯苯和硝基苯生产废水 总被引:2,自引:1,他引:1
采用自制的活性炭粒子群电催化反应器对氯苯和硝基苯生产废水进行处理,考察了槽电流、停留时间对氯苯、硝基苯去除效果的影响。在槽电流20-25A、停留时间30min的条件下,氯苯生产废水中的氯苯质量浓度为3.3~109.9mg/L、苯质量浓度为13.1—395.7mg/L时,氯苯和苯的去除率分别在99%和97%以上,TOC和色度的去除率分别在71%和92%以上;硝基苯生产废水中硝基苯、二硝基苯酚、对硝基氯苯的质量浓度分别为4.5—292.3,83.3—348.0,69.5—93.9mg/L时,硝基苯和二硝基苯酚的去除率分别在96%和99%以上,TOC和色度去除率分别在90%和98%以上,对硝基氯苯在出水中未检出。 相似文献
930.
采用序批式反应器(SBR)处理模拟精对苯二甲酸(PTA)废水,考察了曝气量、沉降时间、进水方式等对对苯二甲酸(TA)生物降解效果的影响。实验结果表明,对于TA质量浓度小于1500mg/L的废水,采用完全曝气SBR运行4h,TA和COD的去除率均能达到95%以上,TA平均去除速率随TA浓度的增加而增大。TA质量浓度为1500mg/L时,曝气量、沉降时间和进水方式是影响其降解效果的主要因素。采用SBR处理高浓度PTA废水可克服污泥膨胀和抗冲击负荷能力弱的问题,且系统的稳定性和PTA废水的处理效果较好。 相似文献