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生物零价铁强化降解典型硝基芳香族化合物的机理研究

时间:2018-03-21 10:07来源:毕业论文
生物零价铁体系的还原转化效果优于零价铁体系和污泥体系两者单独作用,零价铁与厌氧微生物有耦合作用;生物零价铁体系可以将DNAN还原降解更彻底;零价铁对厌氧生物还原降解体系

摘要2,4-二硝基苯甲醚(DNAN)是重要的化工原料,广泛用于化工产品的生产,其生产过程可产生高浓度难降解有机废水。本论文以硝基苯甲醚为目标污染物,对上流式厌氧污泥床反应器(UASB)工艺进行改进,投加零价铁(ZVI)作为强化介质,开发了“ZVI/UASB-好氧”耦合处理工艺,并通过设立对照实验,探究该工艺对DNAN的降解效果;通过对耦合体系还原产物的浓度进行检测,对氧化还原电位(ORP) 、pH及抗冲击负荷能力等参数进行分析,探究微生物与零价铁之间的强化作用机制。实验结果表明:生物零价铁体系的还原转化效果优于零价铁体系和污泥体系两者单独作用,零价铁与厌氧微生物有耦合作用;生物零价铁体系可以将DNAN还原降解更彻底;零价铁对厌氧生物还原降解体系的pH 值有缓冲作用,可提高系统稳定性;体系出水水质稳定,ZVI/UASB反应器可以稳定运行;生物零价铁体系对盐度有更强的承受能力,且可在短时间内适应HRT的变化,具有较强抗冲击负荷能力。19800
关键词    硝基芳香化合物   生物还原  零价铁  稳定性  强化机理
毕业论文设计说明书(论文)外文摘要
Title  The enhanced degradation mechanism of typical nitro-aromatic compound by biological and zero-valent iron process
Abstract
2, 4 - dinitrobenzene (DNAN) is an important chemical raw material, widely used in the production of chemical products. High concentration recalcitrant organic wastewater can be produced from the production process. Zero-valent iron (ZVI)/ upflow anaerobic sludge bed (UASB) - aerobic coupling process was developed to improve the UASB process by adding the ZVI as a medium. To explore the reinforcement mechanism between biological process and ZVI, the concentration of the reduction product was detected, and the oxidation reduction potential (ORP), pH and shock load capacity were analyzed. The experimental results showed that the reduction degradation performance of ZVI/UASB-aerobic coupling process was better than that of ZVI system and sludge system alone, indicating the coupling effect between ZVI and anaerobic microorganisms. DNAN could be completely degraded in ZVI/UASB-aerobic system. The pH of the anaerobic biological degradation system could be buffered by adding ZVI, the stability of the system could be improved significantly. The quality of the water from ZVI/UASB reactor was much more stable. ZVI/UASB-aerobic coupling process has stronger tolerance to salinity and shock load in HRT.
Key words  Nitro-aromatic compounds (NACs)    Biological reduction
Zero-valent iron(ZVI)   Stability     Strengthen  mechanism
 目   次
1引言    1
1.1硝基芳香族化合物的概述    1
1.2硝基芳香废水处理方法    1
1.3 ZVI技术应用现状    4
1.4课题的提出和主要研究内容    5
2实验部分    7
2.1材料与方法    7
2.2实验方法    8
3. 结果与讨论    11
3.1序批实验    11
3.2连续流实验    14
3.3 “ZVI/UASB-好氧”组合工艺的性能评价    17
结  论    22
致  谢    23
参考文献24
1引言
1.1硝基芳香族化合物的概述
硝基芳香族化合物( Nitro-aromatic compounds,简称 NACs)作为一种重要的化工生产原料,被广泛应用于染料、火炸药、农药、医药以及其他的化学化工产品的生产当中,其主要包括硝基苯(NB)、氯代硝基苯、硝基苯胺类等[1]。目前全球每年排放到环境中的苯胺和硝基苯化合物的总和超过万吨;硝基芳香烃属于持久性有毒污染物(Persistnet Toxicusb Stances,TPS) [2],已经被美国环保局(USEPA)列入129种首要污染物(priority pollutant) 名单[3]。 生物零价铁强化降解典型硝基芳香族化合物的机理研究:http://www.youerw.com/huaxue/lunwen_11472.html
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