ABR处理高浓度硫酸盐有机废水的性能

以人工配制的高浓度硫酸盐有机废水作为原水，研究了厌氧折流板反应器（ABR）处理高浓度硫酸盐有机废水的性能。结果表明，在温度为（33．2±0．1）℃、HRT为20～24h以及进水COD、硫酸盐浓度分别为5000和300～1500mg／L的条件下，ABR处理高浓度硫酸盐有机废水的效果较好，对COD的去除率可达90％以上，SO4^2-的还原率稳定在96％。COD／SO4^2-值是影响SRB与MPB竞争关系的重要指标，对COD去除率和SO4^2-还原率都有很大的影响。启动方式对厌氧反应器处理含硫酸盐废水的性能有很大的影响，低硫酸盐负荷启动方式会使MPB取得初始相对优势，SO4^2-还原对厌氧处理过程影响较小。     

ABR处理含硫酸盐废水过程中硫转化的研究

采用厌氧折流板反应器(ABR)处理含硫酸盐废水,考察了硫在反应器中的转化规律,以及HRT和进水COD/SO24-值对硫转化的影响。结果表明,ABR中发生了硫酸盐在第1隔室被大量还原而生成的硫化物,并在之后的各隔室被逐步氧化的现象;HRT越小,硫酸盐的还原率越高;对于低浓度废水,当进水COD/SO24-值2.5时,硫酸盐还原率基本可稳定在90%左右,而当进水COD/SO42-值为1.7～2.5时,硫酸盐还原率可能会大幅下降。     

UASB/曝气觉淀、IC反应器处理高浓度硫盐有机废水

在赤霉素生产过程中产生的高浓度硫酸盐有机废水,处理难度较大.采用UASB/曝气沉淀/IC反应器工艺处理该废水,UASB中的硫酸盐还原菌将硫酸根还原为硫化物,曝气池中的脱硫杆菌则将硫化物氧化为单质硫,并在沉淀池中去除,IC反应器去除COD.系统稳定运行后,对硫酸盐的去除率>90%,对COD的去除率>80%.     

UASB/曝气沉淀/IC反应器处理高浓度硫酸盐有机废水

在赤霉素生产过程中产生的高浓度硫酸盐有机废水,处理难度较大。采用UASB／曝气沉影IC反应器工艺处理该废水,UASB中的硫酸盐还原菌将硫酸根还原为硫化物,曝气池中的脱硫杆菌则将硫化物氧化为单质硫,并在沉淀池中去除,IC反应器去除COD。系统稳定运行后,对硫酸盐的去除率〉90％,对COD的去除率〉80％。     

硫酸盐还原菌的生长因子的探讨

对厌氧处理硫酸盐废水过程中硫酸盐还原菌的生态学进行了综述,详细介绍了硫酸盐还原菌的生理特性、所利用的碳源、氮源的种类,以及影响SRB对废水中硫酸根还原作用的多种因子,如pH值、温度、氧化还原电位等各种因素,并阐明硫酸盐还原菌是一类多样性群体,对硫酸盐废水处理有重要的意义。     

单质铁强化生物还原法处理硫酸盐废水

为提高生物法处理酸性硫酸盐废水的效果,采用间歇试验对生物还原体系的特性进行了研究,重点考察了加入单质铁(Fe0)对硫酸盐还原反应的强化作用.结果表明,pH＞6.5的中性偏酸环境最适合硫酸盐还原菌(SRB)的生长代谢,降低pH值会抑制反应的进行,且初始pH值越低则抑制作用越强.Fe0对硫酸盐还原过程有强化作用,可使体系承受更大的酸性负荷,并明显缩短了反应延迟期,但是对硫酸盐的还原反应速度、最终去除量和还原率几乎没有影响.废水pH值随着硫酸盐还原反应的进行而提高,经过SRB处理后最终可达7.0以上.加入Fe0的体系进行硫酸盐还原反应所消耗的COD较少,△COD/△SO2-4 为0.91～0.98.     

笼状填料式ABR反应器处理啤酒废水启动试验

采用对比试验,分别考察了恒温[(25±2)℃]和变温(10～20℃)条件下自主设计的笼状填料式ABR反应器处理啤酒废水的启动情况,分析了启动阶段COD的变化及其影响因素,并探讨了ABR反应器各隔室pH值的变化与微生物种群及其功能的关系。结果表明,恒温条件下ABR的启动更快;变温条件下ABR有一定的适应期,启动时间相对较长;ABR内pH值的变化规律满足厌氧条件下微生物种群逐室变化及废水中污染物逐级转化的需求;笼状填料具有增加接触面积、改善水力条件和有效截污的作用;启动阶段的容积负荷宜逐步提高。     

硫酸盐还原菌在硫酸盐废水处理中的应用

介绍了硫酸盐废水来源、硫酸盐还原菌（SRB）的分类、生理特性及代谢方式,阐述了SRB处理硫酸盐废水的机理,概括了国内外利用SRB处理重金属废水、高浓度硫酸盐有机废水的应用现状,对SRB处理硫酸盐废水的技术前景进行了展望。     

硫酸盐还原菌固定化填料滤池对硫酸盐的去除

硫酸盐还原作为硫酸盐废水生物处理的第一步反应,其还原效能直接影响后续反应器的运行。采用聚乙烯醇—硼酸二次交联方法将硫酸盐还原菌进行局部包埋固定化处理,制备出生物活性填料并建立起升流式厌氧生物滤池。分析结果表明,该厌氧生物滤池经过短时间的活性恢复培养运行即可具备还原硫酸盐的能力;生物滤池对硫酸盐的还原率稳定在85%以上,出水硫酸盐浓度250 mg/L,且硫酸盐还原反应主要集中在滤层的进水端。通过对填料的静态试验分析,滤池出水中溶解性的硫化物浓度并未达到对SRB的活性产生抑制的程度,生物量是去除硫酸盐的主要决定因素。     

硫酸盐型厌氧氨氧化反应器的启动特征分析

研究了硫酸盐型厌氧氨氧化反应器的启动特征及氧化还原电位对SO24-去除性能的影响。首先启动厌氧氨氧化并逐渐提高容积负荷至0.625kg/(m3.d),然后以(NH4)2SO4为唯一基质,启动硫酸盐型厌氧氨氧化。结果表明,历时212d后成功启动了硫酸盐型厌氧氨氧化反应器,对NH4+-N和SO42-的去除量分别为76.2、68mg/L。反应器出水的pH值低于进水的。当将氧化还原电位提高到(-43±10)mV时,硫酸盐型厌氧氨氧化受到抑制。较高的(NH4)2SO4浓度和低氧化还原电位有利于硫酸盐型厌氧氨氧化反应的发生。此外,该反应器还同时存在自养反硝化作用。     

The effect of polymer addition on granulation in an anaerobic baffled reactor (ABR). Part II: compartmentalization of bacterial populations

The microbial ecology of wastewater treatment plants remains one of the least understood aspects in both aerobic and anaerobic systems, despite the fact that both processes are ultimately dependent on an active biomass for operational efficiency. Ultimately, future developments in anaerobic treatment processes will require a much greater understanding of the fundamental relationships between bacterial populations within the biomass if optimum process efficiency is to be fully realised. This study assesses the influence of polymer addition on granule formation within an ABR and compares the ecology of the biomass in each compartment of two ABRs treating ice-cream wastewater. To our knowledge, this is the first reported characterisation of the microbiology of acidogenic and methanogenic bacteria in the individual compartments of an ABR. The polymer-amended reactor contained sludge that had a greater density of anaerobic bacteria and larger and denser granules than the control reactor, indicating that polymer addition possibly contributed to the retention of active biomass within the ABR. The average fraction of autofluorescent methanogens was lower, with 1.5% being in the initial compartments of the ABRs, compared to the last compartment which had 15%, showing that each compartment of an ABR had a unique microbial composition. Partial spatial separation of anaerobic bacteria appeared to have taken place with acidogenic bacteria predominating in the initial compartments and methanogenic bacteria predominating in the final compartments. Scanning electron micrographs have revealed that the dominant bacteria in the initial compartments of the ABR (Compartments 1 and 2) were those which could consume H2/CO2 and formate as substrate, i.e. Methanobrevibacter, Methanococcus, with populations shifting to acetate utilisers, i.e. Methanosaeta, Methanosarcina, in the final compartments (Compartments 3 and 4). In addition, there appeared to be a stratified structure to the bacterial genera present within the granules.     

Long term competition between sulfate-reducing and methane-producing bacteria for acetate in anaerobic biofilm

A long term competition between sulfate-reducing bacteria (SRB) and methane-producing bacteria (MPB) for acetate was investigated using a laboratory scale anaerobic fluidized bed. When the synthetic wastewater composed of acetate and sulfate was fed at a low organic loading rate, averages of the remaining acetate and sulfate concentrations were 1.7 mg Cl⁻¹ and 78.5 mg l⁻¹, respectively. During several months of this acetate limited operation the methane production rate as well as the microbial mass of MPB declined gradually, whereas the amount of reduced sulfate along with the microbial mass of SRB increased, which apparently indicates that SRB out-compete MPB in the biofilm at lower acetate concentrations. On the other hand, MPB were able to form a biofilm faster than SRB at higher acetate concentrations presumably due to MPB's higher ability to adhere carrier surfaces compared with SRB. Kinetic constants for both species in the biofilm were determined and compared with those reported for pure MPB and SRB cultures. Based on the kinetic mechanism of this competition, operational conditions which would support methanogenesis by suppressing sulfate reduction were identified.     

Interactions between methanogenic,sulfate-reducing and syntrophic acetogenic bacteria in the anaerobic degradation of benzoate

Effect of sulfate on the anaerobic degradation of benzoate was investigated by using the chemostat-type reactors at 35°C. The benzoate concentrations were equivalent to 1250–10000 mg.l⁻¹ in COD (chemical oxygen demand) and the sulfate concentrations were equivalent to 167–1670 mg.l⁻¹ in sulfur (S). Interactions between the methane-producing bacteria (MPB) and sulfate-reducing bacteria (SRB) were dependent strongly on the ratio of COD/S in wastewater. The MPB consumed 99% of the available electron donors at COD/S ratio of 60, but consumed only 69% at ratio of 1.5, and 13% at 0.75. The biochemical reactions and the bacterial composition in the biomass were also governed by the COD/S ratio. At high COD/S ratios (3.0 or higher), benzoate was degraded mainly to methane via acetate and hydrogen/formate. The degradation of benzoate required the syntrophic association between the hydrogen-producing acetogens such as Syntrophus buswellii and hydrogen-consuming MPB, plus Methanothrix-like MPB. On the other hand, at low COD/S ratio (1.5 or lower), benzoate was consumed mainly by SRB, converting sulfate into sulfide and suppressing the methane production. The anaerobic degradation of benzoate was partially inhibited when sulfide concentration was high.     

Correlation of bacterial communities supported by different organic materials with sulfate reduction in metal-rich landfill leachate

Several different organic materials, typical of those used in passive treatment systems for mine influenced water, were tested for their ability to support sulfate-reducing bacteria and sulfate reduction in an anaerobic biological reactor (ABR). The quantity of sulfate-reducing bacteria (SRB) in each organic material, as determined using quantitative polymerase chain reaction (q-PCR) of the dissimilatory sulfite reductase (dsr) gene, correlated with the initial C/N ratio of each material. Potential sulfate reduction rates measured in the laboratory ranked silage > compost = molasses/hay > cattails > pulp mill biosolids and correlated with the q-PCR estimates of SRB in the submerged materials. A comparison of bacterial communities using 16S rRNA gene clone library sequencing revealed similar distribution of clones among the phyla Bacteroidetes, Firmicutes and Proteobacteria for silage, compost and molasses/hay after 174 days of exposure in the seepage water. Silage, the most successful material tested, contained more δ-Proteobacteria-related sequences than the other materials and Spirochaetes-related clones were more abundant in silage than in compost or molasses/hay. According to sequenced dsr clones, the SRB community in silage differed from that for compost and molasses/hay, with fewer Desulfovibrio- and more Desulfomicrobium-related sequences in the silage. Pulp mill biosolids used in the ABR since 2004 contained an overall bacterial community that was more diverse than those for the freshly submerged organics, but only Desulfovibrio desulfuricans-related sequences were found in the dsr library.     

两相厌氧工艺处理高盐纤维素醚废水的研究

采用接种特定污泥的两相厌氧反应器处理高盐纤维素醚废水,重点考察了启动过程及其处理效果。试验结果表明,当产酸相的HRT为18 h时,其所能承受的最大容积负荷为8.18kg/(m3.d),此时其对COD的去除率为20%左右;当产甲烷相的HRT为24 h时,其所能承受的最大容积负荷为5.5 kg/(m3.d),此时其对COD的去除率为35%左右;产甲烷相对COD的去除率与产酸相出水的酸化度呈显著正相关。在产酸相进水COD为6 000 mg/L、产甲烷相进水pH值为7的条件下,当产酸相进水pH值为6、HRT为18 h及产甲烷相的HRT为48 h时,系统的处理效果较佳,出水COD为1 800 mg/L,对COD的总去除率可达70%左右。     

Methanogenic granular sludge as a seed in an anaerobic baffled reactor

This paper reviews the importance of phase separation in anaerobic wastewater treatment, characteristics of anaerobic baffled reactor (ABR), properties of anaerobic granular sludge, granulation process and advantages of granular sludge over nongranular sludge. The performance data of ABR and its modified configurations with regard to carbonaceous matter removal by using various seed sludges are compared. It is concluded that enhanced wastewater treatment efficiencies can be achieved with methanogenic granular seed sludge in an ABR because of a number of advantages associated with granular biomass over nongranular aggregates.     

The effect of polymer addition on granulation in an anaerobic baffled reactor (ABR). Part I: process performance

The stability and performance of an anaerobic baffled reactor (ABR) treating an ice-cream wastewater at several organic loading rates have been investigated. Specifically, it was determined whether an ABR would promote phase separation and if a polymer additive was capable of enhancing granule formation in an ABR. In order to achieve these goals, two ABRs, having identical dimensions and configurations, were used to study the above objectives using a synthetic ice-cream wastewater. The ABR proved to be an efficient reactor configuration for the treatment of a high-strength synthetic ice-cream wastewater. An organic loading rate of around 15 kg CODm(-3) d(-1) was treated with a 99% COD removal efficiency. From the jar test and inhibition assay, it was concluded that Kymene SLX-2 was the most effective and least inhibitory polymer tested. The methane yield was higher in the polymer-amended reactor compared to the control reactor. In addition, polymer addition resulted in a considerably higher degree of biomass retention and lower solids washout from the ABR. Consequently, it demonstrated that there was a considerable potential for sludge conditioning in ABRs by facilitating better biomass retention within the reactor which in turn led to better process performance. Granulation was achieved in both ABRs within 3 months. However, the granules from the polymer-amended reactor appeared earlier and were generally larger and more compact, although this was not quantified in detail during the present study. The main advantage of using an ABR comes from its compartmentalised structure. The first compartment of an ABR may act as a buffer zone to all toxic and inhibitory material in the feed thus allowing the later compartments to be loaded with a relatively harmless, balanced and mostly acidified influent. In this respect, the latter compartments would be more likely to support active populations of the relatively sensitive methanogenic bacteria and partly explains why the best granules and the highest methane yield were obtained in Compartment 2. It is unlikely that a complete separation of phases (acidogenic and methanogenic) occurred within the ABRs since methane production was observed in all compartments, although this was low (approximately 40% of all gas composition) in Compartment 1, becoming higher (approximately 70%) in the following compartments.     

复合嗜盐菌剂强化处理高盐有机废水的中试研究

通过中试研究了投加复合嗜盐菌剂对厌氧反应器启动的影响以及对高盐有机废水生化处理的强化作用.结果表明,投加复合嗜盐菌剂能够加快厌氧反应器的启动,在70 d内就完成了启动过程;复合菌剂能够有效改善生化系统对TOC的去除效果,对TOC的去除率由投菌前的50%左右提高至70%以上.对原水进行脱氨降氰预处理后再采用中试装置进行处理,对TOC的去除率可达85.5%.     

Nitrate stimulation of indigenous nitrate-reducing, sulfide-oxidising bacterial community in wastewater anaerobic biofilms

The role of the nitrate-reducing, sulfide-oxidising bacteria (NR-SOB) in the nitrate-mediated inhibition of sulfide net production by anaerobic wastewater biofilms was analyzed in two experimental bioreactors, continuously fed with the primary effluent of a wastewater treatment plant, one used as control (BRC) and the other one supplemented with nitrate (BRN). This study integrated information from H(2)S and pH microelectrodes, RNA-based molecular techniques, and the time course of biofilm growth and bioreactors water phase. Biofilms were a net source of sulfide for the water phase (2.01 micromol S(2-)(tot)m(-2)s(-1)) in the absence of nitrate dosing. Nitrate addition effectively led to the cessation of sulfide release from biofilms despite which a low rate of net sulfate reduction activity (0.26 micromol S(2-)(tot)m(-2)s(-1)) persisted at a deep layer within the biofilm. Indigenous NR-SOB including Thiomicrospira denitrificans, Arcobacter sp., and Thiobacillus denitrificans were stimulated by nitrate addition resulting in the elimination of most sulfide from the biofilms. Active sulfate reducing bacteria (SRB) represented comparable fractions of total metabolically active bacteria in the libraries obtained from BRN and BRC. However, we detected changes in the taxonomic composition of the SRB community suggesting its adaptation to a higher level of NR-SOB activity in the presence of nitrate.     

ABR处理低浓度有机废水的启动方式研究

对ABR处理低浓度有机废水的启动方式进行了试验研究.结果表明:固定HRT、逐步提高进水COD浓度的启动方式,可使ABR反应器于90 d内完成启动,其对COD的去除率达到80%,系统运行较稳定,但污泥颗粒比较松散;而固定进水COD浓度、缩短HRT的启动方式,49 d就可使ABR对COD的去除率达到80%,且污泥颗粒化程度较高.