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1.
采用水解酸化一好氧膜生物工艺对弹药销毁废水中TNT进行降解试验研究。结果表明,共代谢外加碳源对TNT的生物降解影响显著。无共代谢外加碳源的情况下,HRT=40h,TNT的去除率仅为53.4%。有共代谢外加碳源的情况下,外加碳源COD与TNT提供COD比值宜大于4.8,系统对TNT的去除率可高达99%。温度对水解酸化影响重大,当温度低于15℃时,水解酸化对TNT去除率低于33.3%,而当温度高于20℃时,水解酸化对TNT的去除率不小于83%。  相似文献   

2.
水解酸化-缺氧法对采油废水有较好的处理效果,采用GC/MS技术对水解酸化-缺氧法处理采油废水过程中污染物的迁移降解进行的研究表明:水解酸化段和缺氧段对采油废水中碳原子为C6~C9、分子量为100~140的有机物均有较好的降解能力.其中,在水解酸化段中酮类、芳烃得到较好的降解,缺氧段中酚类和醚类化合物降解明显.水解酸化-缺氧工艺对于采油废水中的甲苯和二甲苯具有较好的降解能力.  相似文献   

3.
讨论了中国南方某城市自来水厂饮用水中的多环芳烃残留规律以及现有净水工艺对多环芳烃的去除效果。研究结果表明,该自来水厂饮用水中检出多环芳烃以2~4环芳烃为主,强致癌性高环数多环芳烃均在检出限以下,且多环芳烃总量未超出中国供水行业标准(2000年)的相关限值。各处理工艺段中,砂滤过程对多环芳烃的去除效果最好,相较于原水对多环芳烃总量的去除率可达64%。  相似文献   

4.
通过在堆肥中加入经过驯化的降解菌这种土壤有机污染生物修复技术 ,对堆肥中多环芳烃的浓度变化进行监测 ,从而了解降解菌对堆肥中多环芳烃的降解作用。实验结果表明 ,降解菌的加入能明显地提高多环芳烃的降解率 ,本次实验中 ,菲、芴的去除率提高了 2 5 %左右 ,芘的去除率提高了约 4 5 %。  相似文献   

5.
青霉菌对印染废水吸附脱色及深度处理的研究   总被引:1,自引:0,他引:1  
利用青霉菌P-1(Penicillium sp.)对2种染浴废水中的染料进行吸附去除,研究结果表明,吸附处理3h,黑色和红色染浴废水色度基本被去除,去除率分别达98.0%和74.5%,但去色处理后废水的CODCr值仍偏高。对去除色度的废水进一步用活性污泥进行深度处理,黑色和红色废水的CODCr去除率分别为75.9%和89.7%。青霉菌菌丝通过吸附作用从废水中抽提出的染料分子在有染料降解细菌L-1和L-2的降解池中脱色降解,菌丝吸附脱色能力得到再生。  相似文献   

6.
焦化废水属高浓度难降解工业有机废水,其中所含的多环芳烃属难降解有机物,且对环境产生毒害作用。为探索生物强化技术去除焦化废水中多环芳烃类化合物,采用选择性培养和多级富集的方法,以联苯为模型化合物,并作为惟一碳源,从焦化厂废水和污泥中分离和筛选得到6株联苯降解菌。通过逐渐提高底物浓度的方法驯化菌株后,从中筛选出降解效率最高的联苯降解菌株WIS-01,在此基础上进行菌属鉴定、细菌生长情况及联苯降解性能的研究。实验结果表明,3 d内菌株WIS-01对联苯的降解率可达99%以上,可耐受联苯的最高质量浓度为2 g/L。通过形态学、生理生化鉴定和16S rDNA序列比对分析,确定菌株WIS-01属于假单胞菌属,同源性达95%,命名为Pseudomonas sp.WIS-01。  相似文献   

7.
水解酸化.缺氧法对采油废水有较好的处理效果,采用GC/MS技术对水解酸化-缺氧法处理采油废水过程中污染物的迁移降解进行的研究表明:水解酸化段和缺氧段对采油废水中碳原子为C6-C9、分子量为100—140的有机物均有较好的降解能力。其中,在水解酸化段中酮类、芳烃得到较好的降解,缺氧段中酚类和醚类化合物降解明显。水解酸化-缺氧工艺对于采油废水中的甲苯和二甲苯具有较好的降解能力。  相似文献   

8.
降解菌对堆肥中多环芳烃降解作用的研究   总被引:5,自引:0,他引:5  
通过在堆肥中加人经过驯化的降解菌这种土壤有机污染生物修复技术,对堆肥中多环芳烃的浓度变化进行监测,从而了解降解菌对堆肥中多环芳烃的降解作用。实验结果表明,降解菌的加人能明显地提高多环芳烃的降解率,本次实验中,菲、芴的去除率提高了25%左右,芘的去除率提高了约45%。  相似文献   

9.
张衍  郑炜  刘锐  李伟  李荧  陈吕军 《环境工程学报》2012,6(12):4355-4360
对化学合成橡胶碱洗废水进行了有机组分和可生化性分析,废水主要含有氯甲烷、六甲苯、异丁醇、甲醇等污染物质,生化降解实验中废水TOC可在6d内从60.9mg/L下降至0.0mg/L,可生化降解性好,适于生化处理。选择混凝.生物接触氧化组合工艺对废水进行处理,采用优化条件(pH=8、PAC=40mg/L、PAM=8mg/L)进行混凝,碱洗废水COD去除率为9.95%~72.94%(平均31.51%);混凝后的碱洗废水与冲洗废水1:5混合进行接触氧化处理,在HRT为36h的情况下,COD去除率为65.6%-72.6%(平均70.4%),出水COD为134~331mg/L,满足企业废水排放市政管网的要求;同时,实验发现COD去除率与COD容积负荷存在指数函数变化关系。  相似文献   

10.
硝基苯类化合物生物降解菌的筛选及性能研究,是制药、染料等行业废水达标的重要基础。以浓度梯度升高法筛选到一株硝基苯厌氧降解菌Klebsiella oxytoca NBA-1。考察了该菌对氧气的需求,以及在厌氧条件下,温度、pH值、外加葡萄糖及硝基苯初始浓度等环境因子对菌株降解硝基苯能力的影响,并进一步讨论菌株对氯取代硝基苯类化合物的降解情况。结果表明,该菌在厌氧条件下生长比好氧条件下慢,但降解速度更快;厌氧降解硝基苯的最佳pH值和温度和分别为8.3和30~35℃;加入0.3%~0.5%的葡萄糖可促进降解,且对300mg/L以下的硝基苯均有降解能力;该菌能将4-氯硝基苯转化为4-氯苯胺,并进一步脱氯为苯胺。研究结果可为硝基苯及含氯硝基苯的处理工艺选择提供相关的参考依据。  相似文献   

11.
In the event of a gasoline spill containing oxygenated compounds such as ethanol and MTBE, it is important to consider the impacts these compounds might have on subsurface contamination. One of the main concerns commonly associated with ethanol is that it might decrease the biodegradation of aromatic hydrocarbon compounds, leading to an increase in the hydrocarbon dissolved plume lengths. The first part of this study (Part 1) showed that when gasoline containing ethanol infiltrates the unsaturated zone, ethanol is likely to partition to and be retained in the unsaturated zone pore water. In this study (Part 2), a controlled field test is combined with a two-dimensional laboratory test and three-dimensional numerical modelling to investigate how ethanol retention in the unsaturated zone affects the downgradient behaviour of ethanol and aromatic hydrocarbon compounds. Ethanol transport downgradient was extremely limited. The appearance of ethanol in downgradient wells was delayed and the concentrations were lower than would be expected based on equilibrium dissolution. Oscillations in the water table resulted in minor flushing of ethanol, but its effect could still be perceived as an increase in the groundwater concentrations downgradient from the source zone. Ethanol partitioning to the unsaturated zone pore water reduced its mass fraction within the NAPL thus reducing its anticipated impact on the fate of the hydrocarbon compounds. A conceptual numerical simulation indicated that the potential ethanol-induced increase in benzene plume length after 20 years could decrease from 136% to 40% when ethanol retention in the unsaturated zone is considered.  相似文献   

12.
The distribution profiles and pathways of polynuclear aromatic hydrocarbons in the surroundings of Ruseifa landfill area in Jordan were investigated for surface sediments, leachate, and groundwater. The total concentration of 16 polycyclic aromatic hydrocarbons (PAHs) in sediments ranged from 286 to 1704 ppm with an average value of 751 ppm. Meanwhile, concentrations of PAH in groundwater ranged between 7.1 and 12.6 ppm with an average value of 9.1 ppm. The PAH in leachate varied between 0.10 and 0.40 with an average value of 0.29 ppm. The overall PAH distribution profiles appeared to be similar for leachate and groundwater dominated by 2–3 rings system molecules. While, the sediments profile was dominated by 4–6 rings system molecules which indicated the loss of low molecular weight compounds of PAH and accumulation of higher molecular weight of PAH under prevailing semiarid and hot climatic conditions.  相似文献   

13.
Fujima S  Ohura T  Amagai T 《Chemosphere》2006,65(11):1983-1989
An analytical method for the determination of gaseous and particulate chlorinated polycyclic aromatic hydrocarbons (ClPAHs) was investigated. By means of this method, concentrations and isomer profiles of the 27 target ClPAHs could be analyzed. To evaluate the usefulness of the method for analyzing ClPAH emissions, laboratory-scale scorching tests were performed on polyvinylidene chloride (PVDC) plastic wrap over a flame of the gas burner. Only seven of the target ClPAHs were detected, and all compounds detected had 2, 3, or 4 rings. The detected ClPAHs were present in both the particulate phase and the gaseous phase, but they were present at higher concentrations in the gaseous phase than in the particulate phase. Relationships between the number of chlorine substituents on the naphthalene/phenanthrene rings and the overall concentration and the percentage in the particulate phase were also investigated.  相似文献   

14.
《Chemosphere》2007,66(11):1983-1989
An analytical method for the determination of gaseous and particulate chlorinated polycyclic aromatic hydrocarbons (ClPAHs) was investigated. By means of this method, concentrations and isomer profiles of the 27 target ClPAHs could be analyzed. To evaluate the usefulness of the method for analyzing ClPAH emissions, laboratory-scale scorching tests were performed on polyvinylidene chloride (PVDC) plastic wrap over a flame of the gas burner. Only seven of the target ClPAHs were detected, and all compounds detected had 2, 3, or 4 rings. The detected ClPAHs were present in both the particulate phase and the gaseous phase, but they were present at higher concentrations in the gaseous phase than in the particulate phase. Relationships between the number of chlorine substituents on the naphthalene/phenanthrene rings and the overall concentration and the percentage in the particulate phase were also investigated.  相似文献   

15.
Dec J  Haider K  Bollag JM 《Chemosphere》2003,52(3):549-556
Phenolic compounds originating from plant residue decomposition or microbial metabolism form humic-like polymers during oxidative coupling reactions mediated by various phenoloxidases or metal oxides. Xenobiotic phenols participating in these reactions undergo either polymerization or binding to soil organic matter. Another effect of oxidative coupling is dehalogenation, decarboxylation or demethoxylation of the substrates. To investigate these phenomena, several naturally occurring and xenobiotic phenols were incubated with various phenoloxidases (peroxidase, laccase, tyrosinase) or with birnessite (delta-MnO(2)), and monitored for chloride release, CO(2) evolution, and methanol or methane production. The release of chloride ions during polymerization and binding ranged between 0.2% and 41.4%. Using the test compounds labeled with 14C in three different locations (carboxyl group, aromatic ring, or aliphatic chain), it was demonstrated that 14CO(2) evolution was mainly associated with the release of carboxyl groups (17.8-54.8% of the initial radioactivity). Little mineralization of 14C-labeled aromatic rings or aliphatic carbons occurred in catechol, ferulic or p-coumaric acids (0.1-0.7%). Demethoxylation ranged from 0.5% to 13.9% for 2,6-dimethoxyphenol and syringic acid, respectively. Methylphenols showed no demethylation. In conclusion, dehalogenation, decarboxylation and demethoxylation of phenolic substrates appear to be controlled by a common mechanism, in which various substituents are released if they are attached to carbon atoms involved in coupling. Electron-withdrawing substituents, such as -COOH and -Cl, are more susceptible to release than electron-donating ones, such as -OCH(3) and -CH(3). The release of organic substituents during polymerization and binding of phenols may add to CO(2) production in soil.  相似文献   

16.
Amir S  Hafidi M  Merlina G  Hamdi H  Revel JC 《Chemosphere》2005,58(4):449-458
The fate of 16 polycyclic aromatic hydrocarbons (PAHs), targeted by the USEPA agency, has been investigated during composting of lagooning sludge. Composting shows efficient decrease of the content and the bioavailability of each PAH. Biodegradation and sorption are suggested as the main mechanisms contributing to this decrease. During the stabilization phase of composting, extensive microbial degradation of PAHs, mainly those with a low number of aromatic rings, was achieved following development of intense thermophilic communities. However, partial sorption of PAH to non-accessible sites temporarily limits the mobility mainly of PAHs with a high number of aromatic rings plus acenaphthene and acenaphthylene, and allows them to escape microbial attack. During the maturation phase, the development of a mesophilic population could play an important role in the degradation of the remaining PAH. During this phase of composting, PAH sequestration and binding of their oxidative metabolites within new-formed humic substances might also explain PAH decrease at the end of composting. The tendency of change of content or bioavailability of various PAH compounds during composting is found to be strongly related to the number of their aromatic rings, their molecular weight and structure.  相似文献   

17.
The capability of different white rot (WR, Heterobasidion annosum, Phanerochaete chrysosporium, Trametes versicolor) and ectomycorrhizal (ECM, Paxillus involutus, Suillus bovinus) fungal species to degrade different aromatic compounds and the absorption of 3-chlorobenzoic acid (3-CBA) by ECM pine seedlings was examined. The effect of aromatic compounds on the fungal biomass development varied considerably and depended on (a) the compound, (b) the external concentration, and (c) the fungal species. The highest effect on the fungal biomass development was observed for 3-CBA. Generally the tolerance of WR fungi against aromatic compounds was higher than that of the biotrophic fungal species. The capability of different fungi to degrade aromatic substances varied between the species but not generally between biotrophic and saprotrophic fungi. The highest degradation capability for aromatic compounds was detected for T. versicolor and H. annosum, whereas for Phanerochaete chrysosporium and the ECM fungi lower degradation rates were found. However, Paxillus involutus and S. bovinus showed comparable degradation rates at low concentrations of benzoic acid and 4-hydroxybenzoic acid. In contrast to liquid cultures, where no biodegradation of 3-CBA by S. bovinus was observed, mycorrhizal pines inoculated with S. bovinus showed a low capability to remove 3-CBA from soil substrates. Additional X-ray microanalytical investigations showed, that 3-CBA supplied to mycorrhizal plants was accumulated in the root cell cytoplasm and is translocated across the endodermis to the shoot of mycorrhizal pine seedlings.  相似文献   

18.
Optical investigations of the exhausts emitted by internal combustion (i.c.) engines and a stationary burner were performed, in order to assess their relative role as sources of organic matter to the atmosphere. Extinction spectra of air-diluted exhausts in the 200-400 nm u.v. band reveal the expected existence of gaseous trace-species (NO, NO2 and SO2) and carbonaceous particulate matter (soot). In addition, after subtracting the absorption contribution from known species, a strong residual absorption band remains below 250 nm, which is attributed to organic aromatic matter, involving no more than two aromatic rings. A set of ex situ extinction and laser induced fluorescence (LIF) experiments were carried out on condensed combustion-water samples. Extinction measurements from the water samples show absorption spectra similar to those observed from air-diluted samples, which are attributed to low volatility organic compounds, as they are trapped in the condensed phase. Combining the indications of extinction data for both air-diluted and condensed samples, it is suggested that the absorbing species might be molecular clusters of one/two aromatic rings. LIF spectra from condensed samples evidence two fluorescence bands, centered above 300 and 400 nm, respectively, whose intensities correlate with the combustion regimes. Analogous optical analysis on rain samples, collected in an urban area, showed that rain absorption and fluorescence spectra are similar to those found in condensed exhaust samples, which is consistent with the prevailing contribution of i.c. engines to the urban air pollution. The combined experimental data suggest that the absorbing and fluorescent species trapped in the condensed samples are organic (aromatic) compounds, involving mostly one two aromatic rings structural units, since they do not absorb above 250 nm. The overall molecular weight of the trapped material is likely heavy as they show low volatility.  相似文献   

19.
光催化氧化降解垃圾渗滤液中溶解性有机物   总被引:3,自引:0,他引:3  
研究了UV-TiO2光催化氧化降解垃圾渗滤液过程中溶解性有机物(DOM)的变化特征。结果表明:在适宜条件下,UV-TiO2光催化氧化降解垃圾渗滤液的色度、COD和DOC的去除率分别可达97%、72%和60%;紫外光谱分析说明渗滤液DOM中包括多种含有共轭双键、羰基的大分子有机物及多环芳香类化合物,不同光催化处理液中DOM具有基本一致的结构单元和官能团;红外光谱分析说明渗滤液DOM中含有大量包括羟基、羧基、氨基和苯环的芳香族化合物,在光催化处理液中这几种官能团都能被有效降解;GC/MS分析结果表明,渗滤液DOM中含有72种有机污染物,醇类、羧酸和酮类分别为25、14和12种;在光催化72 h处理液中,有机物减少为44种;酯类和醇类较多,分别为12种和16种;酮类8种,羧酸没有检出。  相似文献   

20.
以啤酒厂废水处理厂UASB中的厌氧污泥为种泥,葡萄糖为基质,研究了厌氧序批式反应器产氢。控制反应器内pH为4.0~4.5,温度为(36±1)℃,水力停留时间为8 h,当进水葡萄糖浓度为4 000 mg/L,容积负荷为12 kg/(m3.d)条件下,该厌氧序批式反应器实现了连续高效厌氧产氢。生物气中的氢气含量约为48%~53%,基质产氢率为1.1 mol/mol葡萄糖,COD去除率为15%~25%,最大比产氢速率为84.5 mol/(kg VSS.d)。液相末端发酵产物中乙醇和乙酸的含量占液相末端发酵产物总量的80%以上,表明该反应器内进行的是乙醇型发酵厌氧产氢。厌氧序批式反应器完全可以实现连续高效厌氧产氢,比较适用于日处理量较小的高浓度含糖废水。  相似文献   

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