苯酚对厌氧颗粒污泥活性的抑制效应和恢复

通过间歇培养的方式,研究了苯酚对EGSB反应器中颗粒污泥产甲烷活性的抑制和恢复,并通过测定颗粒污泥中辅酶F420、胞外多聚物（ECP）等的含量,研究苯酚对厌氧颗粒污泥微生物的毒性作用。结果表明,不同浓度的苯酚对厌氧颗粒污泥的产甲烷活性都有一定抑制,苯酚浓度越高,抑制程度越严重。如果将苯酚从生物体中迅速去除,产甲烷活性可以逐渐恢复。苯酚对厌氧颗粒污泥中辅酶F420 及胞外多聚物ECP的分泌都有抑制作用。     

厌氧膨胀颗粒污泥床反应器的国内研究与应用现状

厌氧膨胀颗粒污泥床(expanded granular sludge bed,EGSB)反应器作为第三代厌氧反应器的典型代表,相比于上流式厌氧污泥床(UASB)反应器具有更高的容积负荷和抗冲击性能,且其还有占地小以及可产生沼气能源等优点,因而被广泛应用于多种高浓度有机废水处理。本文介绍了EGSB反应器的结构原理与运行流程;统计分析了近些年国内EGSB反应器的相关文献及其由小试到工程化的发展历程;概述了EGSB反应器在甲烷化、厌氧氨氧化(ANAMMOX)、生物制氢、同步脱氮除硫方面的研究进展;综述了产甲烷EGSB反应器与生物膜法、序批式活性污泥法和传统活性污泥法等工艺联用的工程应用现状,指出这些工艺均表现出良好的单体去除效果和较理想的整体去除效果,且EGSB反应器在与新兴技术的耦合上也表现出较好的前景。     

EGSB反应器运行过程中颗粒污泥微生物相解析

本文研究了EGSB反应器运行过程中颗粒污泥的形态,微生物相及优势菌群的分布状况.结果表明,随着运行时间和有机负荷的提高,反应器中颗粒污泥的粒径逐渐增大,且污泥床底部颗粒污泥的粒径大于上部的污泥粒径,呈明显的分层现象.在扫描电镜下观察颗粒污泥的微生物相,运行初期甲烷丝菌属为优势菌群;随着有机负荷的提高,甲烷丝菌逐渐减少,甲烷杆菌占优势;待反应器稳定运行后,菌群类型更加丰富多样,多种产甲烷菌混栖.同时,观察得知EGSB反应器不同高度颗粒污泥的形态和微生物相分布也表现出特有的规律性.     

折流式厌氧反应器启动的关键因素探讨

厌氧折流板反应器(ABR)是一种具有分阶段多相厌氧反应器工艺思想(SMPA)的新型高效厌氧反应器,ABR反应器前面隔室中以产酸菌为优势菌群,后面隔室中以产甲烷为优势菌群,使消化反应的产酸相和产甲烷相沿程得到分离,参与厌氧消化过程的微生物能够生长于各自最佳的生长环境中,使厌氧消化过程的效率大大提高。厌氧折流板反应器的启动跟多因素有关,研究证明低有机负荷,长停留时间是反应器启动的关键,直接接种厌氧颗粒污泥有助于反应器的快速启动。在合适的条件下,反应器内可形成良好的按沿程分布优势菌属的颗粒污泥。     

厌氧氨氧化颗粒污泥的快速形成

以好氧硝化颗粒污泥与厌氧氨氧化生物膜作为接种污泥,在缺氧条件下利用EGSB反应器培养厌氧氨氧化颗粒污泥。根据反应器内污泥性状以及运行效果,随时调整反应器的进水基质浓度以及上升流速等关键控制因素,加快厌氧氨氧化颗粒污泥的快速形成。同时考察系统的脱氮效能、粒径分布、厌氧氨氧化颗粒污泥表面形态以及内部结构与微生物分布情况。反应器运行80 d后,培养出成熟的厌氧氨氧化颗粒污泥,平均粒径为0.556 mm;89 d时,总氮去除负荷达4.758 kg N·m-3·d-1。FISH表明颗粒污泥中厌氧氨氧化菌为优势菌种,同时SEM与TEM观察表明颗粒污泥是由多个小颗粒聚集形成,而且形状不规则,内部结构排列紧密。     

甲烷化反硝化厌氧氨氧化耦合中关键营养菌群的变化

分以产甲烷颗粒污泥为接种污泥,在UASB反应器实现了甲烷化耦合反硝化厌氧氨氧化。采用荧光定量PCR(QPCR)和荧光原位杂交(FISH)技术分析了耦合过程中关键营养菌群的绝对数量、相对丰富度和空间分布的变化。UASB反应器运行250 d后,NO~-_2-N、NO~-_3-N、NH~+_4-N和COD的去除率分别为99.99%、99.99%、48%和75%;细菌、产甲烷菌、反硝化菌、厌氧氨氧化菌/亚硝酸盐还原酶基因(nir S,nir K)和N_2O还原酶基因(nos Z)的相对丰富度分别为89.2%、10.8%、11.7%、0.964%、(9.52%,0.902%)和1.22%。耦合过程中,形成了具有明显分层结构的甲烷化耦合反硝化厌氧氨氧化颗粒污泥(外层细菌,内部古细菌)。     

低浓度污水厌氧生物处理国内外发展现状

回顾了污水厌氧生物处理工艺的发展历程,着重介绍了升流式厌氧污泥床(UASB)、两级系统、厌氧膨胀颗粒污泥床(EGSB)和厌氧折流板反应器(ABR)等厌氧生物处理工艺处理低浓度污水的国内外发展现状.     

EGSB反应器在微氧条件下去除焦化废水中挥发酚

以厌氧和间歇微氧条件为参照,分析EGSB反应器在连续微氧条件下对焦化废水中挥发酚的去除,在反应器运行过程中,进水挥发酚质量浓度在10.09～201.34 mg·L-1之间,微氧反应器有很好的抗冲击负荷能力,挥发酚的去除率保持在98％左右,温度降低后,使微氧反应器挥发酚的去除率由99％降到27％；微量的氧有利于EGSB反应器的稳定运行,反应器能够降解一些在纯厌氧情况下不能去除的难降解物质和有毒物质；颗粒污泥内部的产甲烷菌对于微量氧的加入并不敏感；微氧反应器中颗粒污泥的微生物种群丰富,从外到内微生物分层生长,依次为好氧菌、兼性菌、厌氧菌.     

厌氧氨氧化颗粒污泥的快速形成

以好氧硝化颗粒污泥与厌氧氨氧化生物膜作为接种污泥,在缺氧条件下利用EGSB反应器培养厌氧氨氧化颗粒污泥。根据反应器内污泥性状以及运行效果,随时调整反应器的进水基质浓度以及上升流速等关键控制因素,加快厌氧氨氧化颗粒污泥的快速形成。同时考察系统的脱氮效能、粒径分布、厌氧氨氧化颗粒污泥表面形态以及内部结构与微生物分布情况。反应器运行80 d后,培养出成熟的厌氧氨氧化颗粒污泥,平均粒径为0.556 mm;89 d时,总氮去除负荷达4.758 kg N·m^-3·d^-1。FISH表明颗粒污泥中厌氧氨氧化菌为优势菌种,同时SEM与TEM观察表明颗粒污泥是由多个小颗粒聚集形成,而且形状不规则,内部结构排列紧密。     

污泥厌氧消化功能微生物群落结构的研究进展

污泥厌氧消化处理技术因其具有无害化、资源化和稳定化的特征备受关注。污泥厌氧消化涉及水解发酵、产氢产乙酸和产甲烷多种微生物,并发挥不同的功能。本文介绍了污泥厌氧消化体系中常见的细菌(门水平)和古菌（属水平）群落,如拟杆菌门（Bacteroidetes）、变形菌门（Proteobacteria）、厚壁菌门（Firmicutes）、绿弯菌门（Chloroflexi）、螺旋体门（Spirochaetes）（细菌）和甲烷杆菌属（Methanobacterium）、甲烷八叠球菌属（Methanosarcina）、甲烷短杆菌属（Methanobrevibacter）、鬃毛甲烷菌属（Methanosaeta）（古菌）等。同时也综述了影响厌氧体系中的微生物群落结构的因素,如pH、营养物质、温度、氨氮(NH₄⁺-N)及有毒有害物质等。最后展望了稳定同位素标记、宏基因组学和蛋白质组学等分子生物技术在探查微生物功能方面的应用前景,为进一步分析厌氧体系中未识别的功能微生物提供技术支撑。     

Comparative evaluation of full‐scale UASB reactors treating alcohol distillery wastewaters in terms of performance and methanogenic activity

In this study, two full‐scale upflow anaerobic sludge blanket (UASB) reactors, namely TUASB and CUASB, at the wastewater treatment plants of the Tekirdaǧ Alcohol (Raki) and Canakkale Alcohol (Cognac) distilleries were investigated in terms of performance, acetoclastic methanogenic capacity and microbial composition. The results were compared with a previously studied other UASB reactor (IUASB) at the wastewater treatment plant of the Istanbul Alcohol (Raki) Distillery from which the two reactors (TUASB and CUASB) were seeded. The IUASB reactor performed well achieving COD removal efficiencies of no lower than 85% at organic logding rates (OLRs) in the range of 6–11 kg COD m⁻³ day⁻¹ between 1996 and 2001. During the last one year of operation, between 2000 and 2001, performance of the CUASB reactor in terms of COD removal efficiency was 70–80% at OLRs in a range of 1–4.5 kg COD m⁻³ day⁻¹ whereas it was 60–80% at OLRs in a range of 2.5–8.5 kg COD m⁻³ day⁻¹ in the TUASB reactor. At the end of year 2000, specific methanogenic activity (SMA) tests were carried out to determine potential loading capacity and optimum operating conditions of the IUASB, CUASB and TUASB reactors. The potential methane production (PMP) rates of the CUASB, IUASB and TUASB reactors were measured as 230 cm³ CH₄ gVSS⁻¹ day⁻¹, 350 cm³ CH₄ gVSS⁻¹ day⁻¹ and 376 cm³ CH₄ gVSS⁻¹ day⁻¹ respectively. When the PMP rates were compared with actual methane production (AMP) rates obtained from the three UASB reactors, AMP/PMP ratios were evaluated to be 0.18, 0.12 and 0.13 for CUASB, TUASB and IUASB reactors respectively. This showed that the CUASB, TUASB and IUASB reactors were using only 18%, 12% and 13% of their potential acetoclastic methanogenic capacity respectively. These results can be interpreted that the three UASB reactors were underloaded compared with their potential acetoclastic methanogenic capacities. It was, therefore, recommended that the three UASB reactors should be loaded at higher organic loading rates or sludge withdrawn in order to maintain an AMP/PMP ratio of 0.6–0.7, which can ensure desired reactor performance with safer operation. Results of epifluoresence microscopic examinations showed that the percentage of total autofluorescent methanogens was approximately 30% of the total population in sludges from the TUASB and IUASB reactors whereas it was 20% in sludge from the CUASB reactor. The two UASB reactors treating raki distillery wastewaters contained sludges having a higher percentage of autofluorescent methanogenic population and higher acetoclastic methanogenic activity. Copyright © 2004 Society of Chemical Industry     

Changes to bacterial community make‐up in a two‐phase anaerobic digestion system

Changes to microbial populations in a two‐phase anaerobic digestion system were studied over 34 weeks. Numbers of autofluorescent methanogenic and non‐methanogenic bacteria decreased significantly during start‐up, but did not change markedly either in the acid reactor or the upflow anaerobic filter for the remainder of the study. Although the proportion of autofluorescent methanogens increased in the acid reactor, the numbers of viable methanogens decreased 590‐fold. The numbers of viable methanogens increased 10‐fold in the port, decreased 10‐fold in the effluent and there was almost no change in the drain of the upflow anaerobic filter. The data indicated that bacterial attachment in the upflow anaerobic filter gave a 90% COD removal and a methane yield of 0.33 m³ CH₄ kg⁻¹ COD removed at an organic loading rate of 7 kg COD m⁻³day⁻¹. Epifluorescence microscopy of the seed sludge revealed a diverse methanogenic population of equally dominant groups of medium rods and filaments with Methanococcus, short rods, long rods and Methanosarcina also present. The medium rod‐shaped species remained the most dominant group in the acid reactor. As the volatile fatty acid concentration increased in the acid reactor the number of Methanosarcina and filament species decreased, becoming the least dominant groups. At the end of the operation, Methanococcus species were the dominant group in the upflow anaerobic filter having been washed from the biofilm. © 2000 Society of Chemical Industry     

Digestion of pre‐treated food waste in a hybrid anaerobic solid–liquid (HASL) system

The hybrid anaerobic solid–liquid (HASL) system was developed to be used in industrial‐scale operations to minimize the amount of food waste for disposal in Singapore. Thermal pre‐treatment of food waste at 70 °C for 2 h (experiment E1) or at 150 °C for 1 h (experiment E2) facilitated the hydrolytic and acidogenic processes in the acidogenic reactor and methanogenesis in the methanogenic reactor in the HASL system. The highest dissolved chemical oxygen demands in the effluents from the acidogenic reactors were 17 575, 19 980 and 24 235 mg dm^?3 in the control with food waste without thermal pre‐treatment and experiments E1 and E2, respectively. The maximum concentrations of methanogens in the methanogenic reactor were 2.3 × 10⁷, 3.8 × 10⁷, 4.3 × 10⁷ cells cm^?3 for the control and experiments E1 and E2, respectively. However, the performances of the methanogenic phase in terms of specific activity of methanogens did not differ significantly for the control and experiments E1 and E2. Use of thermally pre‐treated food waste halved the time to produce the same quantity of methane in comparison with anaerobic digestion of fresh food waste. The fluorescent measurements of co‐enzyme F₄₂₀ and oligonucleotide probe Arc915 specifically bound (hybridized) with 16S rRNA were used for monitoring of methanogens during anaerobic digestion of food waste. There was a linear correlation between these parameters and the concentration of methanogens in the effluent from the methanogenic reactor. Copyright © 2005 Society of Chemical Industry     

复合式厌氧折流板反应器启动中的相分离特性

采用复合式厌氧折流板反应器(HABR)处理模拟啤酒废水,考察了其快速启动过程中的处理效能及相分离特性。结果表明:HABR可在33 d内完成启动,对COD的去除率92%;pH值在反应器前后端分别呈酸性和中性,促进了产酸菌和产甲烷菌的分离;厌氧系统内挥发性脂肪酸(VFAs)质量浓度的变化可以用于判断产酸作用和产甲烷作用之间是否处于动态平衡状态;HABR的产气量和末端出水VFAs质量浓度呈负相关关系,证明产甲烷菌的代谢活性逐渐增强。在快速启动过程中,HABR表现出了明显的生物相的选择和分离现象。     

Quantitative analysis of microbial community structure in two-phase anaerobic digesters treating food wastewater

An acidogenic reactor with a 0.5-L working volume and a methanogenic digester with a 5-L of working volume were operated for 150 days on a continuous mode to investigate the structure of a microbial community during food wastewater treatment. During the steady state of anaerobic digestion, volatile solids (VS) removal efficiency in the pilot plant was approximately 65%. The bacterial population was higher than any other methanogens detected during the entire anaerobic process and treatment of raw food wastewater. Methanomicrobiales (MMB), Methanosarcinales (MSL), and Methanobacteriales (MBT) were detected during digestion. The methanogenic population present in the acidogenic reactor was directly affected by the archaeal community in raw food wastewater. However, the shift of microbial community in the methanogenic digester was relatively gradual. The performance of methanogenic digester might be more related to the change of microbial metabolism affected by the physicochemical properties of the input substrate.     

Staged and non-staged anaerobic filters: Microbial activity segregation,hydrodynamic behaviour and performance

This work describes a comparative study of staged and non-staged anaerobic filters for treating a synthetic dairy waste under similar operating conditions. The effect of increasing the substrate concentration from 3 to 12 g COD dm⁻³ at a constant hydraulic residence time (HRT) of 2 days was evaluated with respect to overall reactor performance, biogas production, volatile fatty acids profiles along the height, methanogenic and acidogenic activity distribution, and hydrodynamic behaviour. The potential maximum specific methanogenic activity against acetate, hydrogen, propionate and butyrate and the lactose specific activity were determined for sludge sampled from three different points in each reactor, under two operating conditions (influent COD of 3 and 9 g COD dm⁻³). Although all trophic groups involved in the anaerobic process were found throughout the reactors, it was possible to identify different specific sludges at different heights in both reactors. Performances of the two configurations were very similar under the operating conditions tested and the plug flow behaviour of the staged reactor was clearly reduced when the influent concentration increased from 3 to 9 g COD dm⁻³. © 1998 Society of Chemical Industry     

Methanogens in paddy rice soil

The population, methanogenic activities and dominant species of methanogenic bacteria in paddy rice soils under different conditions were studied. Application of fertilizer, especially organic manure and submergence with deep water increased the population and methanogenic activities of methanogenic bacteria in rice soils. No large differences was observed among the population of methanogen in rice soils from different depths of 0-5, 5-13 and 13-18 cm. Soils, which developed from different parent material and had various use history, had notably different cell numbers and activities of methanogenic bacteria. Methanogenic activities in soils developed from fluvo-aquic soil were obviously higher than those in soils developed from quaternary red soil and coastal saline soil, and those in upland soil were pronounced lower than those in rice soil. The methanogenic bacteria that survived in air-dried rice soil could form methane after addition of water and incubation. The dominant species of methanogens were Methanobacterium formicicum, Methanobrevibacter sp., Methanosarcina mazeii and Methanosarcina barkeri. This revised version was published online in August 2006 with corrections to the Cover Date.     

活性艳蓝经多相类芬顿预处理前后对厌氧污泥性能的影响

以蒽醌类染料活性艳蓝为目标污染物,探讨了其对产甲烷菌的抑制机理;分析了其经多相类芬顿预处理前后对厌氧污泥EPS、粒径分布、金属离子含量的影响;同时对活性艳蓝的降解途径进行了探究。结果表明,活性艳蓝对产甲烷菌具有代谢毒性甚至生理性毒性;其进入厌氧反应器后,会造成COD去除率降低;颗粒污泥粒径减少,污泥中钙、镁离子浓度分别由40.5和16.2 mg·L^-1降低到22.5和6.8 mg·L^-1,污泥的稳定性与絮凝性变差。而经多相类芬顿预处理后,COD去除率可达90%以上,厌氧颗粒污泥EPS总量、蛋白质含量、多糖含量分别增大到98.7、69.9和28.8 mg·(g VSS)^-1,为保持颗粒污泥的活性与稳定性提供了保障。多相类芬顿体系所产生的羟基自由基首先攻击活性艳蓝的三嗪基团及不饱和共轭键的蒽醌结构,继而生成邻苯二甲酸、苯甲酸,再被降解为丁酸、草酸、乙酸等小分子羧酸,从而降低了其毒性,有利于后续厌氧生物处理的进行。     

High-Rate Anaerobic Treatment of Malting Waste Water in a Pilot-Scale EGSB System Under Psychrophilic Conditions

The feasibility of the expanded granular sludge bed (EGSB) system for the treatment of malting waste water under psychrophilic conditions was investigated by operating a pilot-scale 225·5 dm³ EGSB-reactor system in the temperature range from 13 to 20°C. The concentration of chemical oxygen demand (COD) in the malting waste water was between 282 and 1436 mg dm⁻³. The anaerobically biodegradable COD of the waste water was about 73%, as determined in the batch bioassays. During reactor operation at 16°C, the COD removal efficiencies averaged about 56%, at organic loading rates (OLR) ranging between 4·4 and 8·8 kg COD m⁻³ day⁻¹ and a hydraulic retention time (HRT) of approximately 2·4 h. At 20°C, removal efficiencies were approximately 66% and 72%, respectively, at OLRs of 8·8 and 14·6 kg COD m⁻³ day⁻¹, corresponding to HRTs of 2·4 and 1·5 h. The specific methanogenic activity with the sludge from the reactor, assessed on acetate and volatile fatty acids mixture as substrates, significantly increased (80%) in time, indicating an enrichment of methanogens and acetogens even at the low temperatures applied. These findings are of considerable practical importance because they indicate that anaerobic treatment of low strength waste waters at low temperature might become a feasible option. © 1997 SCI.