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1.
河口滨岸潮滩沉积物-水界面N、P的扩散通量   总被引:46,自引:6,他引:46  
选择了长江河口及上海海滨岸作为研究对象,分析了潮滩上覆水、沉积物孔隙水中营养物质N、P的含量,并初步估算了潮滩沉积物-水界面向N、P的扩散通量。上覆水中NH4^ -N含量分布在0.0082-2.56mg/L,NO2^--N灾0.03-0.58mg/L,NO3^--N为0.69-5.38mg/L之间,溶解态磷(DP)的含量为0.035-0.53mg/L之间;表层沉积物孔隙水中NH4^ -N的含量为0.0025-1.35mg/L,NO2^-的含量为0.0055-0.20mg/L,NO3^--N的含量为0.61-1.14mg/L,DP的含量为0.11-0.53mg/L;计算表明,沉积物-水界面间NH4^ -N、NO2^-、NO3^--N和DP的扩散通量分布范围分别为0.11-0.99、-0.39-0.0019、-3.09--0.12和-0.48-0.12μg(cm^2.d)之间。研究揭示,沉积物是水体中N的重要蓄积库和P的可能输入源。  相似文献   

2.
介绍了采用中和混凝 水解酸化 生物接触氧化 化学除磷工艺对可发性聚苯乙烯 (EPS)废水的处理工艺。在废水中的CODCr、TP、SS、NH3 N分别为 194 0mg L、112mg L、5 92mg L、2 3 6mg L的条件下 ,废水经过处理后 ,出水CODCr、TP、SS、NH3 N分别为 70mg L、0 38mg L、2 6mg L、0 32mg L ,均可达到《污水综合排放标准》中的一级标准 ,废水中CODCr、TP、SS、NH3 N的平均去除率分别为 96 4 %、99 3%、95 6 %、98 6 %。  相似文献   

3.
两段活性污泥法处理味精废水的中试研究   总被引:1,自引:0,他引:1  
白晓慧 《环境工程》2001,19(1):26-27
采用两段活性污泥法处理味精废水 ,试验规模 0 5m3/h ,当进水CODCr浓度 16 80~ 70 30mg/L,NH3 N浓度 2 0 6~ 1999mg/L时 ,经石灰中和 ,空气吹脱对离交废水的预处理后 ,出水CODCr<10 0 0mg/L。试验中 ,兼氧池和一段好氧池污泥浓度保持在 6 0 0 0~ 80 0 0mg/L之间 ,二段好氧池保持在 40 0 0~ 6 0 0 0mg/L之间。生物处理总停留时间 5 0h。在离交废水预处理中 ,pH中和至 9 5~ 10 ,鼓气量在 10 0m3/h左右 ,水温加至 5 5℃左右 ,经 8h ,可将原水NH3 N从12 0 0 0mg/L左右 ,脱除 6 5 %以上 ,出水氨氮可达 40 0 0mg/L左右。  相似文献   

4.
钝顶螺旋藻处理氨氮废水的研究   总被引:3,自引:0,他引:3  
螺旋藻是一种营养丰富的新型保健食品,利用含氮废水为培养基,研究螺旋藻以NH4-N的处理效率,着重探讨利用生活污水培养螺旋藻的可行性,及其对生活污水的处理效果。研究证明,在NH4-N浓度小于40.0mg/L时,其对NH4-N的去除率最大,可达93%左右。在体积百分比生活污水为80%时,添加NaHCO38mg/L,对NH4-N的去除率达91.8%。同时对螺旋藻化学组分及含铁、锌、锰、铜、硒进行分析,生活污水培养螺旋藻,其所含有机物和氮源,可供螺旋藻生长繁殖,使废水资源化,并减少环境污染;藻粉可作为饲料添加剂,是使废水变为蛋白源的有效途径。  相似文献   

5.
CWO技术处理高浓度焦化废水的工业应用研究   总被引:1,自引:0,他引:1  
采用 2 0 0 L/ d CWO小型工业试验装置对高浓度焦化废水进行处理试验研究 ,结果表明 CWO技术装置对处理高浓度焦化废水 (CODCr,10 0 0 0~ 130 0 0 mg/ L、NH3- N12 0 0~ 2 10 0 mg/ L)具有良好的技术可行性 ,废水经处理后 (催化反应时间 30~ 4 5 min) ,废水中 CODCr、NH3- N的去除率即可达到 99%以上 ,处理水中的 CODCr、NH3- N浓度均可达到国家排放标准 (CODCr<10 0 mg/ L、NH3- N<15 mg/ L ) ,且废水的脱色、除臭效果明显。对于不同浓度焦化废水的处理 ,CWO技术及装置表现出了很好的适应性。国产化 2 0 m3/ d CWO工业装置对焦化废水的连续处理运行表明 ,CWO技术在国内已达到工业化应用水平 ,并具有较好的经济性。  相似文献   

6.
焦化废水生物流化床系统脱氮中试研究   总被引:6,自引:0,他引:6  
杨平  王彬  石炎福 《环境工程》2002,20(4):14-17
以厌氧流化床、缺氧流化床作生物反应器 ,聚合物多孔高分子颗粒作微生物固定化载体 ,采用厌氧 缺氧 好氧工艺进行了焦化废水处理中试研究。结果表明 :当系统稳定运行时 ,进水NH3 N、CODCr、酚平均浓度为 5 39 5mg L、14 88mg L、2 4 7 7mg L时 ,出水NH3 N、CODCr酚平均浓度分别为 14 3mg L、2 5 2 4mg L、0 2mg L ;厌氧流化床、缺氧流化床反应器中存在厌氧氨氧化反应 ,在这 2个阶段NH3 N分别去除 9 8%和 3 3%。该生物流化床系统脱氮技术对现有焦化废水活性污泥法处理系统的改造具有指导意义  相似文献   

7.
蚀刻液废水厌氧氨氧化脱氮性能研究   总被引:3,自引:0,他引:3       下载免费PDF全文
李祥  黄勇  朱莉  袁怡  李大鹏  张丽 《中国环境科学》2012,32(12):2199-2204
采用上流式生物膜反应器接种厌氧氨氧化污泥,研究了印制电路板行业蚀刻液废水厌氧氨氧化脱氮可行性.结果表明,蚀刻液废水作为NH4+-N源时,其所携带的物质对厌氧氨氧化污泥活性具有毒性作用.当蚀刻液废水稀释到NH4+-N浓度150mg/L进入反应器14d后,厌氧氨氧化氮去除速率从3.2kg/(m3·d)下降到1.2kg/(m3·d).但是通过驯化培养可以很好地缓解蚀刻液对厌氧氨氧化污泥的毒性影响.经过110d的驯化,蚀刻液废水稀释到NH4+-N浓度300mg/L进入反应器后并未出现明显的抑制现象.厌氧氨氧化氮去除速率从1.6kg/(m3·d)上升到6.0kg/(m3·d).说明通过驯化培养后,厌氧氨氧化工艺能够很好的运用到PCB行业高NH4+-N废水的处理.  相似文献   

8.
屠宰废水具有有机物含量高、可生化性较好等特点,因此生化处理是屠宰废水的主要工艺。某公司对屠宰废水采用"气浮-水解酸化-SBR"工艺进行处理,废水处理结果表明,当废水进水SS、COD cr、BOD5、NH3-N平均浓度分别为580 mg/L、1 900 mg/L、1 140 mg/L、54 mg/L时,出水SS、COD cr、BOD5、NH3-N平均浓度分别为45 mg/L、55 mg/L、15 mg/L、10 mg/L,出水水质指标满足《肉类加工工业水污染物排放标准》(GB 13457-92)的一级排放标准要求,废水中SS、COD cr、BOD5、NH3-N平均去除率分别为92%、97%、98.5%、72%。  相似文献   

9.
通过计算N和DO的质量平衡,研究饮用水生物处理小试工艺中是否存在NH4 -N的非硝化去除途径,并探讨其可能机制.结果表明,当生物流化床和生物滤池进水NH4 -N浓度大于2 mg/L时,前者进水的NH4 -N、NO2--N和NO3--N之和比出水高出0.91 mg/L,后者理论上消耗的DO比实际多约2.90 mg/L,说明这2种工艺中均有氮亏损现象发生,一部分NH4 -N通过与DO无关的非硝化作用被去除.对非硝化去除途径的分析表明,因为反应器对磷元素和有机物的利用不随氮亏损发生变化,可以排除掉同化作用和反硝化作用;因为反应器进水低碳高氮的特性NO2--N的积累与发生氮亏损的废水生物处理系统相似,据此提出在生物膜缺氧内部发生、通过短程硝化和厌氧氨氧化的偶联(或OLAND反应)将NH4 -N和NO2--N同时转变为N2脱除的自养脱氮是饮用水生物处理中氮亏损的可能途径.  相似文献   

10.
短程硝化反硝化去除高氨氮猪场废水中的氮   总被引:8,自引:0,他引:8       下载免费PDF全文
对比分析了运用缺氧/好氧SBR工艺处理2种COD/N不同的废水的脱氮效果,结果表明,2种废水的脱氮主要是通过短程硝化反硝化实现的,反应器中的NH4+-N浓度和pH值是控制亚硝酸型硝化的重要因素,经过部分厌氧消化的废水由于保持了较高的COD/N,脱氮效果明显好于完全厌氧消化废水,NH4+-N去除率达到98%以上,但出水反硝化不完全,投加乙酸钠后出水NOx--N由100~120mg/L减少到10~20mg/L,乙酸钠投加量以275mg/L为宜.  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.
Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.  相似文献   

13.
Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury (HgT), combinative mercury (Hgc) and gaseous mercury (HgG), and content of total organic carbon (TOC), but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of (HgG,/HgT)1992〉(HgG/HgT)1996〉〉(HgG/HgT)2000. A simple outline of Hg release in landfill could be drawn: with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants (e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum) are capable of enriching more Hg than herbaceous plants.  相似文献   

14.
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   

15.
The influence of the nonionic surfactant Tween 80 on pentachlorophenol (PCP) oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration (CMC). Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.  相似文献   

16.
Decomposition of alachlor by ozonation and its mechanism   总被引:1,自引:0,他引:1  
Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.  相似文献   

17.
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   

18.
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   

19.
以三峡大学的校园河道求索溪为研究对象,利用综合水质标识指数法确定求索溪水质类别,分析其水质时空变化规律,并利用对应分析法得出求索溪中不同监测点的主要污染因子.研究结果表明:求索溪整体的综合水质标识指数为7.423,整体水质为劣V类(地表水环境质量标准GB 3838-2002)且黑臭.从时间变化来看,求索溪4月份的水质最差,5月份次之,4、5月份所有监测点的水质都劣于V类且黑臭;8月份水质最好,水质为Ⅳ类;从空间分布来看,8个监测点综合水质标识指数均超过6.0,水质为劣V类,其中6号监测点的水质相对最好,监测点3号的水质相对最差;对应分析法得出求索溪的整体水体污染程度受总氮因子的影响最大,其次为总磷.该研究拟为求索溪及类似校园河道的水环境治理研究提供基础依据和参考.  相似文献   

20.
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   

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