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1.
投加絮凝剂是促使微生物快速形成污泥颗粒的一种有效手段,通过研究在不同絮凝剂下生成的生物絮体的形态和沉降性能,推荐选用聚合氯化铝(PAC)作为促进光合细菌球形红细菌形成污泥颗粒的絮凝剂。PAC的最佳投加量范围为140-160mg/L,其中,PAC投加量150mg/L时,促进污泥颗粒化的效果最好。考察球形红细菌污泥颗粒降解氯苯的环境条件,结果表明球形红细菌污泥颗粒降解氯苯的最佳条件为好氧、pH7.0、30°C。  相似文献   

2.
虽然好氧颗粒污泥(Aerobic Granular Sludge,AGS)具有沉降性能好、高效脱氮除磷以及抗冲击负荷等优点,但是该技术仍然存在颗粒化进程缓慢及容易解体等技术瓶颈。因此,如何克服上述瓶颈是实现好氧颗粒污泥技术在实际污水处理推广的关键。近年来,酰基高丝氨酸内酯(Acyl Homoserine Lactone,AHL)介导的微生物群感效应(Quorum Sensing,QS)成为微生物领域的研究热点,而有研究报道采用AHLs介导的微生物群感效应对活性污泥快速颗粒化以及颗粒稳定有积极作用,具体作用途径包括投加AHLs促进活性污泥胞外聚合物(Extracellular Polymeric Substances,EPS)的分泌并影响微生物群落结构。本文首先回顾关于AHLs对污水处理过程中微生物的作用机理,讨论了不同环境因素(包括底物类型、电子受体、污泥浓度、pH值、温度)对微生物产出AHLs数量的影响,总结AHLs外源添加或引入产AHLs功能菌株的方法,进而通过AHLs调控污泥的快速颗粒化和长期稳定。最后,本文提出了AHLs介导的群感效应在好氧颗粒污泥技术上的未来研究方向。  相似文献   

3.
以厌氧颗粒污泥为代表的污泥颗粒化技术具有容积负荷高、节省沉淀分离空间、节能减排、单位投资成本和运行成本低等优点,在废水处理中得到广泛应用。近年来,好氧和缺氧颗粒污泥技术也受到关注,在去除废水中有机物的同时还可实现对氮磷的同步去除,其中好氧颗粒污泥技术已在国外实现了工业应用。文章从厌氧、好氧和缺氧颗粒污泥的起源和发展、运行条件对颗粒形成的影响、废水处理反应器和工程应用等几个方面进行综述和总结,分析了目前颗粒技术在应用中存在的问题,并对污泥颗粒化技术的发展前景进行了展望。  相似文献   

4.
酸性条件下耐酸产甲烷颗粒污泥的培养及特性*   总被引:1,自引:0,他引:1  
分别采用中性颗粒污泥和河底沉积物接种运行两个颗粒污泥膨胀床(EGSB)反应器,通过逐级降低pH的运行策略,驯化和培养了耐酸产甲烷颗粒污泥,两个EGSB反应器均能在pH5.8-6.2条件下稳定运行,容积负荷可达5.5-7.5kg COD,(m^3/d),COD去除率约90%;两种颗粒污泥在低pH值下均能保持较高的产甲烷活性,pH5.5时,仍能保持pH7.0时活性的51.8%和55.6%;还对耐酸颗粒污泥的粒径分布、沉降性能、金属元素含量、微观结构及细菌在颗粒表面和内部的分布等进行了研究。  相似文献   

5.
研究了在稳定运行的上流式厌氧污泥床(Upflow Anaerobic Sludge Blanket,UASB)反应器中,对硝基苯酚(p-NP)冲击对反应器活性的影响。采用PCR-DGGE技术监测了反应器受对硝基苯酚冲击后微生物种群多样性的变化。实验结果表明,p-NP冲击对污泥的产甲烷活性和COD去除活性均有严重的抑制,污泥活性的恢复需要较长时间;高浓度冲击比低浓度冲击产生更严重的影响,20mg/L和40mg/Lp-NP冲击后污泥活性的恢复期分别为16d和27d。p-NP冲击后,真细菌和古菌的多样性均发生了显著的变化,而且p-NP冲击对真细菌的影响大于对古菌的影响。p-NP冲击后甲烷产量下降的主要与Methanosaetasp.的活性下降以及Methanomicrobia sp.丰度的下降有关。而冲击后真细菌的主要变化表现为Chloroflexisp.、Bacteroidesp.和Anaerovibrio sp.的丰度均下降;Rheinheimera sp.在受到20mg/Lp-NP冲击时丰度下降,继续受到40mg/Lp-NP冲击时该种群消失。Flavobacteria sp.是p-NP冲击后新出现的细菌种群,可能与p-NP的降解有关。  相似文献   

6.
ABR结合SBR法处理印染废水的研究   总被引:9,自引:0,他引:9  
采用实验室规模的厌氧折流板反应器(ABR)与序批式活性污泥曝气反应器(SBR)结合工艺处理印染废水。通过对ABR-SBR处理系统工艺条件的试验,在ABR段HRT为24~36 h,污泥负荷为0.43~2.46 kg COD/(m3.d),进水pH值为6.5~8.0,温度20℃~35℃;SBR段的溶解氧为2 mg/L,曝气时间为3~10 h,沉淀时间为2 h的条件下,经处理的印染工业废水COD、色度和苯胺去除率分别为32%~95%、89%~99%和50%~98%,其COD为30.0~97.1 mg/L,色度为8~40倍,苯胺浓度为0.20~0.95mg/L,达到了国家一级排放标准。  相似文献   

7.
厌氧生物处理技术因其具有有机负荷高、污泥产量低、能耗低等优点被广泛应用于各种废水处理中。厌氧颗粒污泥具有沉降性能好、微生物浓度高、有机负荷高等优点,极大地提高了废水处理效率。尤其在处理含高氨氮废水中,厌氧颗粒污泥的形成对反应器的高效生物脱氮至关重要。但到目前为止,厌氧反应器中的颗粒污泥形成及废水处理效果还缺乏系统的认识。鉴于此,总结了厌氧反应器中颗粒污泥的形成机制,分析了影响厌氧反应器中颗粒污泥形成的因素,论述了厌氧反应器中厌氧颗粒污泥生长的模拟,最后介绍了厌氧颗粒污泥在国内外的主流应用。厌氧反应器中颗粒污泥的形成是综合因素影响的结果,对影响厌氧颗粒污泥形成的每个因素都需要认真对待,可为在厌氧反应器中颗粒污泥的培育和应用提供理论指导和技术支撑。  相似文献   

8.
采用序批式反应器驯化活性污泥处理造纸废水,观察颗粒污泥的形成过程及浮游动物的变化.结果显示:在污泥驯化初期污泥颗粒化程度低,COD去除能力不高,鞭毛虫纲(Mastigophora)最早出现,随后出现肉足纲(Sarcodina)生物;污泥驯化中期,污泥颗粒化程度增加,污水处理能力提高,以纤毛虫类(Ciliata)为主;污泥驯化稳定期,处理能力达到最大值,污泥颗粒化完成,固着型纤毛虫--钟虫(Vorticella)的出现和增长,标志着活性污泥的成熟.其次,在反应器运行过程中,如果运行条件发生改变或出现异常,如负荷增加、pH异常、营养缺乏等,系统内浮游动物及其活动情况也会发生有规律的变化.  相似文献   

9.
【目的】将厌氧的膜生物反应器(MBR)与微生物燃料电池(MFC)耦合的厌氧电辅助膜生物反应器(E-MBR)应用于实际工业焦化废水处理。【方法】通过正交实验优化了反应器进水的培养条件为PO_4~(3–)14.3 mg/L、Fe~(2+)0.2 mg/L、Fe~(3+)0.1 mg/L、Co~(2+)0.1 mg/L和Mn~(2+)0.2 mg/L。在此条件下考察了该反应器对系统中有机污染物的去除效率及厌氧污泥的污泥特性、产电性能、胞外聚合物(EPS)、微生物群落结构及膜污染的影响。【结果】结果表明,与未优化的培养条件相比,工业焦化废水COD的去除率提高了23%;污泥浓度(MLSS)、比重、沉降速度增加,污泥体积指数(SVI)降低,表明污泥颗粒化及沉降性能提高;污泥中溶解性EPS (SMP)、松散态EPS (LB-EPS)及紧密结合态EPS (TB-EPS)这3种组分中的蛋白质与多糖的比例(P/C)分别降低0.12、0.25和0.16,表明污泥更易于被降解;厌氧污泥的产电性能增强;高通量分子测序结果表明,反应器中污泥的群落结构发生了明显的变化,优势菌群突出;经扫描电镜(SEM)对比结果表明,反应器阴极膜的污染情况也得到了一定的减缓。【结论】优化进水培养条件可以达到使反应器污水处理效率提高、清理周期缩短和运行更稳定等效果,对于工业废水处理技术的节能环保方面提供一定的理论依据。  相似文献   

10.
采用实验室规模的厌氧折流板反应器(ABR)与序批式活性污泥曝气反应器(SBR)结合工艺处理印染废水。通过对ABR-SBR处理系统工艺条件的试验,在ABR段HRT为24~36 h,污泥负荷为0.43~2.46 kg COD/(m3.d),进水pH值为6.5~8.0,温度20℃~35℃;SBR段的溶解氧为2 mg/L,曝气时间为3~10 h,沉淀时间为2 h的条件下,经处理的印染工业废水COD、色度和苯胺去除率分别为32%~95%、89%~99%和50%~98%,其COD为30.0~97  相似文献   

11.
Aerobic granules were cultivated under temporal alternating aerobic and anoxic conditions without the presence of a carrier material in a sequencing batch reactor (SBR) with a high column height/column diameter ratio. The reactor was operated for 6h per cycle (aerobic: 4.75 h, anoxic: 1.25 h). To determine a new parameter for the definition of aerobic granules, a protocol of 4,6-diamidino-2-phenylindole hydrochloride staining and fluorescence image processing was developed. The d(tm) analysis showed that the increase in the chemical oxygen demand (COD) loading rate promoted no more growth of the aerobic granules. It was inconsistent with the results of the analysis of the sludge volume index (SVI) value but matched well with the results of the COD and nitrogen removal of the SBR and the particle size distribution by LS-PSA. The optimum COD loading rate for aerobic granulation in the SBR was 2.52 kg/m(3)d. When d(tm) was correlated with the biomass concentration and the SVI value during the period of granule formation, d(tm) could be used as a more sensitive and accurate parameter for classifying aerobic granules and optimizing the operational conditions for aerobic granulation processes.  相似文献   

12.
Su C  Zhu L  Zhang C  Qi X  Guo Y  Gao R 《Biotechnology letters》2012,34(5):883-888
Aerobic granules for sulphide and ammonium removal were cultivated in a sequencing batch reactor, and the microbial community of the aerobic granules was investigated by denaturing gradient gel electrophoresis. The loading rate increased from 0.15 to 0.9 kg S2? m?3 d?1, and the removal efficiencies of sulphide, chemical oxygen demand, and NH4 +-N were higher than 99, 80, and 98%, respectively. However, sludge settleability became poorer when the loading rate exceeded 0.3 kg S2? m?3 d?1. The denitrifying bacteria in the aerobic granules were Thauera sp., Pseudomonas alcaligenes, and uncultured planctomycetes, indicating that multiple N-removing processes occurred simultaneously in the aerobic granules. These processes could include nitrification and denitrification, aerobic denitrification, and anaerobic ammonia oxidation. Sludge settleability became poorer because of the overgrowth of uncultured Thiothrix sp.  相似文献   

13.
Fang F  Liu XW  Xu J  Yu HQ  Li YM 《Bioresource technology》2009,100(1):59-63
Aerobic granular sludge rich in polyhydroxybutyrate (PHB) was cultivated in a sequencing batch reactor (SBR) by seeding anaerobic granular sludge. The PHB content in aerobic granules was investigated and the experimental results reveal that both influent chemical oxygen demand (COD) and ammonium concentrations had a significant effect on the morphological characteristics and the PHB production of the aerobic granular sludge. At a COD and ammonium concentration of 750 mg/L and 8.5mg/L, respectively, the PHB content of the granules reached 44%, but their poor settling ability, as evidenced by a high sludge volume index, was observed. This was attributed to the outgrowth of filamentous bacteria on the granule surface. However, an increase in the ammonium concentration resulted in an elevated sludge concentration and a decrease in the PHB content in the granules. In this case, the aerobic granular sludge with a regular and compact structure was formed. The results suggest that, through controlling the COD and ammonium concentrations in the influent, the PHB-rich aerobic granular sludge with good settling ability could be cultivated.  相似文献   

14.
The formation and characterization of the aerobic 4-chloroaniline-degrading granules in the three column-type sequencing batch reactors were investigated in this paper. The granular sludge was observed since 15 days after start-up in R2 and R3 which had the high ratio of height to diameter (H/D). Since then and within the subsequent 75 days, the granulation of aerobic sludge was apparently developed by the decreased settling time and gradually increased 4-chloroaniline (4-ClA) concentration to above 400 mg.L(-1) in R1 to R3. The aerobic granules tended to be mature in all reactors continuously operated with 4-ClA loading rates of around 800 g.m(-3).d(-1), and the removal efficiencies of chemical oxygen demand, total nitrogen, and 4-ClA were maintained above 93%, 70%, and 99.9%, respectively. Mature aerobic granules in R1 to R3 featured with the average diameter of 0.78, 1.68, and 1.25 mm, minimal settling velocity of 20.5, 70.1 and 66.6 m.h(-1), specific 4-ClA degradation rates of 0.14, 0.21, and 0.27 g.gVSS(-1).d(-1), and the ratio of proteins to polysaccharides of 8.2, 10.8, and 13.7 mg.mg(-1), respectively. This study demonstrates that the reactor with a high H/D ratio and internal circulation favors the granulation and stabilization of aerobic sludge.  相似文献   

15.
The performance of packed-bed biofilm reactor (PBBR) with self-floating bio-carriers was investigated to treat highly concentrated organic nitrogenous aniline wastewater with a COD value as high as 24,000 mg/L. With 45 vol% of carrier charge inside the reactor, the aniline wastewater can be effectively treated with 94% of COD removal efficiency at a low organic loading rate (OLR) of 0.9 kg COD/(m3 d). The removal efficiency decreased gradually down to 75% when OLR increased to 12.27 kg COD/(m3 d) that corresponded to 1 day of HRT. Separate tests with biofilm alone showed that the conversion contribution of the biofilm was about half of the overall COD conversion by the biofilm plus sludge system at the same OLRs of 3–4 kg COD/(m3 d), and that the biofilm had higher activity than suspended sludge. Ammonium released from decomposed aniline was increased gradually from 500 to 1700 mg/L with the OLR increase from 0.9 to 12.27 kg COD/(m3 d), which resulted in inhibitory effect to the microorganism due to the toxicity of free ammonia. Batch anaerobic toxicity tests showed that the biofilm was less sensitive to toxic compounds than suspended sludge and could tolerate higher concentration of free ammonia.  相似文献   

16.
This paper presents the integrated removal of carbon (measured as chemical oxygen demand i.e. COD) and NO(x)-N by sequentially adapted sludge, studied in an airlift reactor (ALR). Simultaneous removal of COD and nitrate occurs by denitrification (anoxic) and oxidation (aerobic). Aerobic (riser) and anoxic (remaining part) conditions prevail in different parts of the reactor. Studies were carried out in a 42 L ALR operated at low aeration rate to maintain anoxic and aerobic conditions as required for denitrification and COD removal, respectively. The sludge was adapted sequentially to increasing levels of NO(x)-N and COD over a period of 45 days. Nitrate removal efficiency of the sludge increased due to adaptation and degraded 900 ppm NO(3)-N completely in 2h (initially the sludge could not degrade 100 ppm NO(3)-N). The performance of the adapted sludge was tested for the degradation of synthetic waste with COD/N loadings in the range of 4-10. The reduction of COD was significantly faster in the presence of NO(x)-N and was attributed to the availability of oxygen from NO(x)-N and distinct conditions in the reactor. This hypothesis was justified by the material balance of COD.  相似文献   

17.
Aerobic granules were successfully developed at substrate N/COD ratios ranging from 5/100 to 30/100 by weight. By measuring respective respirometric activities of heterotrophic, ammonia-oxidizing, and nitrite-oxidizing bacteria, it was found that the relative abundance of nitrifying bacteria over heterotrophs in aerobic granules was closely related to the substrate N/COD ratios. Results further showed that the populations of both ammonia and nitrite oxidizers were significantly enriched with the increase of the substrate N/COD ratio, while a decreasing trend of heterotrophic population was observed in the aerobic granules. These seem to indicate that high substrate N/COD ratio favors the selection of nitrifying bacteria in the aerobic granules, while the relative activity of nitrifying population against heterotrophic population evolved until a balance between two populations was reached in the aerobic granular sludge community. Moreover, cell elemental composition was correlated with the shift in microbial populations, e.g., the enriched nitrifying population in the aerobic granules resulted in a high cell nitrogen content normalized to cell carbon content. This study provides a good insight into microbial interaction in aerobic granules.  相似文献   

18.
This study investigated the feasibility of improving the stability of aerobic granules through selecting slow-growing nitrifying bacteria. For this purpose, four sequencing batch reactors were operated at different substrate N/COD ratios ranging from 5/100 to 30/100. Results showed that aerobic granules formed in all four reactors, and aerobic granulation was a gradual process evolving from the dispersed seed sludge to mature and stable granules, and the whole granulation process could be divided into three phases, i.e. acclimation phase, granulation followed by granule maturation. The observed growth rate and mean size of mature aerobic granules were found to decrease as the substrate N/COD ratio was increased, while nitrifying population was enriched markedly in aerobic granules developed at high substrate N/COD ratios. The enriched nitrifying population in aerobic granules was responsible for the observed low growth rate of aerobic granules. It seems certain that the substrate N/COD ratio is an important factor in selecting nitrifying bacteria in aerobic granules. Aerobic granules with low growth rates showed strong structure and good settleability in terms of specific gravity, SVI and cell hydrophobicity that further lead to high stability as compared to those having high growth rates. This study demonstrated that the selection of slow-growing nitrifying bacteria through controlling substrate N/COD ratio would be a useful strategy for improving the stability of aerobic granules.  相似文献   

19.
Two SBR reactors were set up to investigate the feasibility of aerobic granulation under the combined selection pressures of hydraulic shear force and substrate loading. Aerobic granulation was studied at superficial upflow air velocity of 3.2 and 2.4 cm/s under an organic loading rate (OLR) range of 6.0-15.0 kg COD/m3d. Good reactor performance and well granule characteristics were achieved in a wide OLR range from 6.0 high up to 15.0 kg COD/m3d at 3.2 cm/s. While under the velocity of 2.4 cm/s, stable operation was limited in the OLR range of 6.0-9.0 kg COD/m3d and failed to operate with granule deterioration under further higher OLRs. The optimal combination of hydrodynamic shear force and loading selection pressure was demonstrated to be an important factor that influence aerobic granulation and govern the granule characteristics and reactor performance.  相似文献   

20.
Aerobic sludge granules are compact, strong microbial aggregates that have excellent settling ability and capability to efficiently treat high-strength and toxic wastewaters. Aerobic granules disintegrate under high organic loading rates (OLR). This study cultivated aerobic granules using acetate as the sole carbon and energy source in three identical sequencing batch reactors operated under OLR of 9–21.3 kg chemical oxygen demand (COD) m−3 day−1. The cultivated granules removed 94–96% of fed COD at OLR up to 9–19.5 kg COD m−3 day−1, and disintegrated at OLR of 21.3 kg COD m−3 day−1. Most tested isolates did not grow in the medium at >3,000 mg COD l−1; additionally, these strains lost capability for auto-aggregation and protein or polysaccharide productivity. This critical COD regime correlates strongly with the OLR range in which granules started disintegrating. Reduced protein quantity secreted by isolates was associated with the noted poor granule integrity under high OLR. This work identified a potential cause of biological nature for aerobic granules breakdown.  相似文献   

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