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Fenton试剂处理酸性染料废水的研究 总被引:25,自引:0,他引:25
采用Fenton试剂处理酸性染料废水,在pH=3,〔FeSO4〕=40mg/L,〔H2O2〕=800mg/L时,酸性媒介漂蓝废水的色度及COD去除率分别达98.6%和80.1%。 相似文献
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介绍了云南金鼎锌业有限公司新建项目选址周围地区环境概况和项目排污简况,从规划、对周围环境的影响、卫生防护距离设置、公众参与调查方面分析了选址的可行性,认为该项目选址可行。 相似文献
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太阳光助Fenton体系氧化降解苯酚废水的研究 总被引:18,自引:0,他引:18
探讨了太阳光助Fenton体系对苯酚的氧化降解。结果表明,太阳光能有效地增强Fenton试剂对苯酚的氧化降解,在晴天较强太阳光照下,Fenton试剂可在较短时间内使较高浓度的苯酚完全矿化。反应体系的初始pH值及Fe^2 用量均对苯酚的氧化降解有明显影响,反应的适宜pH值在3—4的酸性范围内;适量Fe^2 参与的太阳光—Fenton反应有助于苯酚的降解,但过高的Fe^2 用量反而不利于苯酚的降解。实验结果还表明,采用分批多次投加的方式可明显提高氧化剂H202的利用效率,降低H202的消耗量;苯酚废水降解的主要中间产物为苯醌和有机酸;一定程度的太阳光—Fenton预氧化处理可使废水的BOD5/C02cr比值由0.10捉高到0.32,可生化性明显提高。 相似文献
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Experimental data are presented to test and validate a kinetic model for the oxidation of 2-chlorophenol wastewater by photo-assisted Fenton process. The data showed that this process had produced good effects under acidic conductions. Up to 90% 2-chlorophenol was removed after 90-minute reaction time with H2O2 of 25% CODCr. in, while in UV/H2O2 system ordy 16.8% 2-chlorophenol was removed after one hour treatment. The optimal pH in this reaction occurred between pH 3.0 and pH 4.0. The reaction kinetics for photo-assisted Fenton process experimented in this research was investigated. Kinetic models were proposed for the treatment of 2-chlorophenol wastewater. The reaction was found to follow the 2nd order. The equations of reaction kinetics are as follows:-d[RH]/dt=KRH[RH][H2O2]0exp(-KH2o2t);-d[CODCr]/dt=KCODCr[CODCr][H2O2]0exp(-K′t).The prediction of the models was found to be in a good agreement with experimental results, thus confimfing the proposed reaction mechanism. 相似文献
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The superseded female's dilemma: ultimate and proximate factors that influence guarding behaviour of the carpenter bee Xylocopa pubescens 总被引:1,自引:0,他引:1
Both solitary and primitively social nests of the facultatively social carpenter bee Xylocopa pubescens can be found throughout most of the breeding season. In social nests there is reproductive division of labour between a dominant forager and a guarding female. Two types of guarding females can be discerned: the young pre-reproductive guards, and older, formerly reproductive guards. The latter type of guard is found when, after a take-over of reproductive dominance either by a nestmate (mostly a daughter) or an intruder, the defeated female stays in the nest instead of leaving to try and found or usurp another nest. She is then manipulated into the role of a guard. The dominant female profits from the presence of the guard since she protects the nest against pollen robbery by conspecifics (Hogendoorn and Velthuis 1993). We have studied why superseded females might prefer to remain as a guard, rather than try their luck somewhere else. The hypotheses investigated pertain to (1) the difficulty for the defeated female of finding a new nest and of restarting reproductive activities due to (a) ecological constraints (nest and pollen shortage) and (b) the effect of age and wear on the defeated female; (2) the effects of guarding in terms of inclusive fitness. We found that superseded females remained as guards significantly more often when a nestmate (not necessarily close kin) took over reproductive dominance than when an intruder did so. Other factors associated with the decision of the defeated female to stay or leave were her age and the number of her own young still present after the supersedure. The probability of finding or constructing a new nest was lower for old than for young females. After finding a nest, old females produced less brood than young foundresses. As a result of these two factors old superseded females gained, in terms of inclusive fitness, by staying as guards, whereas young females profited from leaving the nest. We interpret these results as an indication that guarding behaviour has evolved due to kin selection. However, kin discrimination apparently did not occur. Therefore we conclude that in this species kin selection is not, in the proximate frame of reference, based on kin recognition and preference for helping kin.
Correspondence to: K. Hogendoorn 相似文献
28.
湿法FGD湿烟囱工艺的问题及对策 总被引:9,自引:1,他引:9
介绍了湿法FGD湿烟囱工艺的可行性和选择该工艺时应考虑的问题,并提出了湿烟道、湿烟囱设计的基本要求。 相似文献
29.
高炉料仓环境条件恶劣,而高炉生产又要掌握料位情况。比较了2种料位计,最终选择了SA—2型料位计。 相似文献
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