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1.
1概述利用厌氧技术处理废水已被广泛地采用,厌氧技术可大致地划分为高负荷厌氧技术和低负荷厌氧技术。一般低负荷厌氧技术容积负荷大约为03—3kgCOD/m3d,污水停留时间为6—30d,高负荷厌氧技术容积负荷大约为6—10kgCOD/m3d,污水停留时间为1d。低负荷厌氧技术具有投资省、运转费用低、抗冲击负荷能力强、污泥产量少等优点,缺点是占地面积大,它的应用受到空间大小的限制。低负荷厌氧技术(以下简称BVF)属于低负荷厌氧技术范畴,如果它能被合理地设计与管理,可以更加有效地发挥低负荷厌氧技术的优…  相似文献   

2.
吴敏  李丹 《上海环境科学》2003,22(4):265-268
采用厌氧水解—好氧和单独好氧处理两种生化方法对蒽醌染整废水进行了平行对照试验。结果表明,厌氧水解—好氧处理方法可有效地提高该废水的可生化程度。当进水CODcr浓度为400mg/L、色度为800倍时,厌氧水解—好氧处理后出水CODcr可达120—170mg/L,CODcr去除率在63%以上,色度降低至150倍,明显优于单一好氧处理的出水水质。  相似文献   

3.
采用酸中和—厌氧—好氧—生物活性炭或化学混凝综合法处理制浆黑液,探讨了酸中和处理的影响因素及厌氧处理对后段好氧处理的影响。结果表明:两种综合处理工艺对黑液中木质素及CODcr的去除有显著效果;厌氧处理比好氧处理对木质素的降解更为有利。生物-物理化学法处理制浆黑液的试验研究  相似文献   

4.
厌氧UASB-好氧工艺处理染料废水的研究   总被引:5,自引:2,他引:5  
报道厌氧-好氧工艺处理染料废水的试验结果。厌氧段采用UASB反应器,好氧段采用普通活性污泥法。试验结果表明,进水COD1150—1300mg/L、色度500倍的染料废水,在厌氧段停留6—10h,可获得60%以上的COD去除率,色度降到50—100倍。后续曝气6h,总COD去除率可达85%-90%,色度降至20倍左右。进出水的光谱分析揭示,染料废水的脱色主要发生在厌氧段.并且通过生物降解作用来实现。从这些结果得出,UASB-好氧工艺是处理染料废水的一种经济有效的方法。  相似文献   

5.
通过污水厌氧消化分离出的一种现称之为“DL—1”的简单菌株,可提高煤转化成甲烷的生物转化率。美国弗吉尼亚工艺研究所和Blacksbunrg州立大学的詹姆斯·费里等声称首先需用化学方法,如用过氧化氢和醋  相似文献   

6.
我国城镇污泥处理处置起步较晚,多元利用途径和产业化推广仍在探索,其中经济性是关系到技术应用路径是否通畅,技术体系能否有效落地的重要因素。“厌氧消化+土地利用”是我国目前城镇污泥处理处置主流技术路线之一。聚焦“常规厌氧消化+土地利用”和“高级厌氧消化+土地利用”2条主流技术路线,基于全流程运行成本统一核算方法,分析不同泥质或技术条件下的经济性特征和变化规律;探讨经济性和技术实施如何相互影响,并通过经济性分析对“厌氧消化+土地利用”技术路线的应用推广提出优化建议。研究结果将为城镇污泥处理处置顶层设计和技术路线选择提供依据,为工程运营单位评估和提升运行水平提供参考,为城镇污泥无害化处理与资源化利用的推广落地提供支撑。  相似文献   

7.
有机废水快速渗滤处理系统中氧化还原环境特征   总被引:7,自引:0,他引:7  
在啤酒废水交替淹水的土柱中安装了铂金和甘汞电极,对淹水—落干期间不同土壤深度的氧化—还原电位进行了测定.结果表明,在100cm深度以上,随淹水—落干交替进行,土壤依次出现厌氧和好氧环境,在100cm浓度以下,土壤中保持厌氧状态.据此将有机废水RI系统划分为不同的氧化—还原带,各带对有机污染物具有不同的净化功能.  相似文献   

8.
利用聚磷菌快速内源性反硝化脱氮研究   总被引:7,自引:0,他引:7  
从部分聚磷菌在缺氧状态下的反硝化吸磷现象出发,探索了利用经过厌氧释磷,菌体内含有大量PHB的聚磷菌进行快速内源性反硝化脱氮的可能性。试验结果表明:聚磷菌在厌氧段充分有效释磷后,在缺氧段初期3—5min内,就能将30—40mg/L的NO^-3;内源性反硝化脱氮去除65%—75%,达到一级排放标准。  相似文献   

9.
“老龄”垃圾渗滤液的厌氧毒性试验研究   总被引:4,自引:0,他引:4  
本文通过厌氧毒性试验(ATA),研究“老龄”垃圾渗滤液对厌氧微生物的毒性抑制作用。试验结果表明,渗滤液的厌氧毒性随着其体积浓度的增加而增强,当渗滤液浓度达80%时,污泥产甲烷活性开始出现中度抑制,而100%渗滤液能够使污泥相对活性下降55.5个百分点,最大产甲烷活性区间滞后14d。渗滤液对污泥的抑制类型是多种毒物共同作用的结果,在低浓度主要表现为代谢毒素,高浓度时表现出生理毒素作用。  相似文献   

10.
目前已经发现了2种微生物脱氯新途径:一是根据好氧氨氧化菌具有反硝化能力,从而在一定条件下反硝化脱氯:二是在功能微生物的作用下,亚硝酸盐与氨离子一起厌氧氨氧化,并且发现了厌氧氨氧化菌与好氧氨氧化菌或甲烷菌能协同耦合在一种有利的微生态环境中。基于以上新途径提出了几种生物脱氟新工艺,包括了:SHARON、ANAMMOX、SHARON—ANAMMOX、CANON、OLAND、NOX工艺、需氧反氨化工艺(Aerobic deammonification)、甲烷化与厌氧氨氧化耦舍工艺。  相似文献   

11.
Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis (DGGE) and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity (both in gene richness and diversity index values) and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor (50 mg/kg) recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos (150 mg/kg) caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos (250 mg/kg) produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes (bands) responded differently to the impact of agrochemicals: four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.  相似文献   

12.
The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.  相似文献   

13.
Several main metabolites of benzo[a]pyrene (BaP) formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone (BP 1,6- quinone), trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (BP 7,8-diol), 3-hydroxybenzo[a]pyrene (3-OHBP), were identified by high-performance liquid chromatography (HPLC). The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that (1) the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; (2) the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; (3) the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% (w/v), concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.  相似文献   

14.
Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter.  相似文献   

15.
In this study an effort has been made to use plant polyphenol oxidases; potato (Solanum tuberosum) and brinjal (Solanum melongena), for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.  相似文献   

16.
RemovalofheavymetalsfromsewagesludgebylowcostingchemicalmethodandrecyclinginagricultureWuQitang,NyirandegePascasie,MoCehuiF...  相似文献   

17.
A study was conducted to compare the diversity of 2-, 3-, and 4-chlorobenzoate degraders in two pristine soils and one contaminated sewage sludge. These samples contained strikingly different populations of mono-chlorobenzoate degraders. Although fewer cultures were isolated in the uncontaminated soils than contaminated one, the ability of microbial populations to mineralize chlorobenzoate was widespread. The 3- and 4-chlorobenzoate degraders were more diverse than the 2-chlorobenzoate degraders. One of the strains isolated from the sewage sludge was obtained. Based on its phenotype, chemotaxonomic properties and 16S rRNA gene, the organism S-7 was classified as Rhodococcus erythropolis. The strain can grow at temperature from 4 to 37℃. It can utilize several (halo)aromatic compounds. Moreover, strain S-7 can grow and use 3-chlorobenzoate as sole carbon source in a temperatures range of 10-30℃ with stoichiometric release of chloride ions. The psychrotolerant ability was significant for bioremediation in low temperature regions. Catechol and chlorocatechol 1,2-dioxygenase activities were present in cell free extracts of the strain, but no (chloro)catechol 2,3- dioxygenase activities was detected. Spectral conversion assays with extracts from R. erythropolis S-7 showed accumulation of a compound with a similar UV spectrum as chloro-cis,cis-muconate from 3-chlorobenzoate. On the basis of these results, we proposed that S-7 degraded 3-chlorobenzoate through the modified ortho-cleave pathway.  相似文献   

18.
Single and joint effects of pesticides and mercury on soil urease   总被引:3,自引:3,他引:3  
The influence of two pesticides including chlorimuron-ethyl and furadan and mercury (Hg) on urease activity in 4 soils (meadow burozem and phaeozem) was investigated. The soils were exposed to various concentrations of the two pesticides and Hg individually and simultaneously. Results showed that there was a close relationship between urease activity and organic matter content in soil. Chlorimuron-ethyl and furadan could both activate urease in the 4 soils. The maximum increment of urease activity by chlorimuronethyl was up to 14%-18%. There was almost an equal increase (up to 13%-21%) in the urease activity by furadan. On the contrary, Hg markedly inhibited soil urease activity. A logarithmic equation was used to describe the relationship (P〈0.05) between the concentration of Hg and the activity of soil urease in the 4 tested soils. Semi-effect dose (ED50) values by the stress of Hg based on the inhibition of soil urease in the 4 soils were 88, 5.5, 24 and 20 mg/kg, respectively, according to the calculation of the corresponding equations. The interactive effect of chlorimuron-ethyl or furadan with metal Hg on soil urease was mainly synergic at the highest tested concentrations.  相似文献   

19.
A field study was conducted in the Taihu Lake region, China in 2004 to reveal the organochlorine pesticide concentrations in soils after the ban of these substances in the year 1983. Thirteen organochlorine pesticides (OCPs) were analyzed in soils from paddy field, tree land and fallow land. Total organochlorine pesticide residues were higher in agricultural soils than in uncultivated fallow land soils. Among all the pesticides, ΣDDX (DDD, DDE and DDT) had the highest concentration for all the soil samples, ranging from 3.10 ng/g to 166.55 ng/g with a mean value of 57.04 ng/g and followed by ΣHCH, ranging from 0.73 ng/g to 60.97 ng/g with a mean value of 24.06 ng/g. Dieldrin, endrin, HCB and α-endosulfan were also found in soils with less than 15 ng/g. Ratios of p,p'-(DDD DDE)/DDT in soils under three land usages were: paddy field > tree land > fallow land, indicating that land usage inlfuenced the degradation of DDT in soils. Ratios of p,p'-(DDD DDE)/DDT >1, showing aged residues of DDTs in soils of the Taihu Lake region. The results were discussed with data from a former study that showed very low actual concentrations of HCH and DDT in soils in the Taihu Lake region, but according to the chemical half-lives and their concentrations in soils in 1980s, the concentration of DDT in soils seemed to be underestimated. In any case our data show that the ban on the use of HCH and DDT resulted in a tremendous reduction of these pesticide residues in soils, but there are still high amounts of pesticide residues in soils, which need more remediation processes.  相似文献   

20.
Common silver barb,Puntius gonionotus,exposed to the nominal concentration of 0.06 mg/L Cd for 60 d,were assessed for histopathological alterations(gills,liver and kidney),metal accumulation,and metallothionein(MT)mRNA expression.Fish exhibited pathological symptoms such as hypertrophy and hyperplasia of primary and secondary gill lamellae,vacuolization in hepatocytes,and prominent tubular and glomerular damage in the kidney.In addition,kidney accumulated the highest content of cadmium,more than gills and liver.Expression of MT mRNA was increased in both liver and kidney of treated fish.Hepatic MT levels remained high after fish were removed to Cd-free water.In contrast,MT expression in kidney was peaked after 28 d of treatment and drastically dropped when fish were removed to Cd-free water.The high concentrations of Cd in hepatic tissues indicated an accumulation site or permanent damage on this tissue.  相似文献   

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