工艺因子对于MFC中能量分配的协同效应分析

微生物燃料电池(MFC)以产电和代谢的方式利用系统能量实现有机物降解。针对运行过程中能量的不同分配需求,以p H、有机负荷、溶解氧、电导率和外电阻为工艺因子,采用正交实验方法优选最佳工艺条件,从而实现MFC能量流调控的目的。研究表明:在实验工况下,最高产电能量转化效率和生物代谢能量利用效率分别为8.74%和66.03%,负荷和外电阻对产电能量转化效率有显著影响,负荷和p H对能量利用效率有显著影响,系统能量主要以生物代谢方式被利用。由此可见,在同等负荷条件下,若将MFC作为电转化单元时应主要控制其外电阻,若需提高MFC的有机物降解能力时p H则是首要控制因素。     

HA@Fe3O4修饰阳极增强微生物燃料电池降解雌激素

类固醇雌激素(SEs)是一类广受关注且危害性较大的新污染物,常规的污水处理工艺难以将其完全去除。腐殖酸(HA)作为一种电子传递中介体,可大幅提高微生物代谢过程中胞外呼吸的电子传递效率。鉴于HA的这种特殊电化学性质,将其应用于微生物燃料电池(MFC)系统,将有望实现在低能耗的前提下对SEs的高效降解。本研究选取17α-乙炔基雌二醇(EE2)作为代表性SEs,利用HA与较强电容性的纳米Fe3O4颗粒形成的金属化合物(HA@Fe3O4)修饰MFC阳极,探究含有EE2的模拟废水在MFC阳极的降解特性。结果表明HA的存在不仅能提高微生物与阳极板之间的电子传递效率,还可显著增加阳极板的电容性进而提高产电性能,其最大功率密度可达522.32 mW/m2。此外,HA@Fe3O4修饰的阳极可显著提高MFC对EE2的降解效率,研究还发现EE2在低浓度范围内可提升MFC的性能,但高浓度时会抑制微生物的活性并降低MFC产电效率。本研究为微生物燃料电池在实际废水中有效应用提供了一定的研究基础。     

连续流微生物燃料电池(MFC)反应器启动及生物颗粒的形成

为了回收废水中有机物蕴含的化学能并改善MFC对COD的去除效果,设计了一种新型厌氧流化床微生物燃料电池(AFB-MFC)用于同步高效废水处理及产电,对AFB-MFC反应器启动及生物颗粒形成进行了研究,并考察启动期内微生物燃料电池产电和废水处理性能以及外电阻对产电性能的影响。结果表明,在确定实验条件下,36d可快速成功启动AFB-MFC反应器并形成生物颗粒;启动期内,间歇运行时AFB-MFC产生的电压优于连续运行,间歇运行时最高电压850mV,而连续运行时下降至680～690mV,并最终稳定;COD去除率随进水负荷增加而增加,AFB-MFC反应器启动成功连续稳定运行后COD去除率可稳定在80.00%～90.41%;在外电阻为100Ω时,AFB-MFC产电性能最好,功率密度可达21.89mW·m-2。     

以加热预处理污泥上清液为底物的微生物燃料电池基础特性

以单室空气阴极微生物燃料电池(MFC)为反应器,考察了以加热预处理污泥上清液为底物的MFC产电情况. 结果表明,污泥90℃下加热3 h时MFC输出功率最高(44.4 mW/m2),是未加热的105倍. 在此预处理条件下,污泥上清液中所含有机物成分最有利于阳极微生物的代谢产电. 加热后的污泥再次加热作为MFC底物产电,输出功率只有5.8 mW/m2. 加热预处理可提高以污泥上清液为底物的MFC的输出功率,且易与现有工艺结合,更接近实际应用.     

乳酸菌微生物燃料电池产电性能及产电机理研究

采用双室微生物燃料电池（MFC）,以乳酸菌为产电微生物,并以葡萄糖为唯一的电子供体,研究MFC的产电性能以及乳酸菌MFC产电机理。在30 ℃下,底物浓度为1.5 g/L时,该MFC的开路电压稳定在500 mV。实验条件下测得该MFC的最大功率密度为393.23 mW/m²,内阻约为500 Ω。利用气相色谱分析乳酸菌MFC产电过程中代谢产物的含量变化,实验数据表明无论是不参与产电的正常代谢途径还是产电过程中,都涉及到乳酸菌的同型乳酸发酵途径、异型乳酸发酵的经典途径和双歧杆菌发酵途径。在乳酸菌MFC运行过程中人为添加乙醇,该实验结果显示乙醇不利于乳酸菌产电,表明乳酸菌的异型乳酸发酵途径是乳酸菌进行产电的关键代谢途径。     

异养反硝化微生物燃料电池脱氮产电性能研究

构建了双室型微生物燃料电池(MFC),探讨了异养反硝化底物降解、产电特性和指示作用。结果表明:有机物是影响异养反硝化微生物燃料电池产电和污水处理性能的关键影响因素,未加入有机物时MFC产电仅有10 m V;MFC的电信号能较好地反映亚硝氮、COD基质浓度的变化情况,因此可用电压变化指示底物的降解过程;在不考虑菌体水解、同化作用所引起氨氮浓度的增加问题时,亦可用时间来指示氨氮的降解过程。     

以沼液为原料的微生物燃料电池产电降解特性

为提高生物质能源利用效率,降低废水处理成本,实验构建单室无膜空气阴极微生物燃料电池(microbial fuel cell,MFC),碳布作为阴阳极材料,将牛粪沼液作为接种液及底物进行产电性能测试,同时考察了MFC对该沼液的降解效果。结果表明,MFC能够利用沼液进行产电,最高输出电压330 mV,内阻10 kΩ,最大功率密度为10.98 mW·m-2,沼液中的不可溶性物质是导致MFC输出电压、功率密度低的重要原因。MFC的运行对沼液中的有机物、氮、磷等物质具有一定的降解能力,24 h内去除率分别达到20.73%、67.82%、72.56%。因此,MFC作为产生电能的新方法,在联合处理沼液等有机废水节能减排方面具有广阔前景。     

以沼液为原料的微生物燃料电池产电降解特性

为提高生物质能源利用效率,降低废水处理成本,实验构建单室无膜空气阴极微生物燃料电池（microbial fuel cell,MFC）,碳布作为阴阳极材料,将牛粪沼液作为接种液及底物进行产电性能测试,同时考察了MFC对该沼液的降解效果。结果表明,MFC能够利用沼液进行产电,最高输出电压330 mV,内阻10 kW,最大功率密度为10.98 mW·m^-2,沼液中的不可溶性物质是导致MFC输出电压、功率密度低的重要原因。MFC的运行对沼液中的有机物、氮、磷等物质具有一定的降解能力,24 h内去除率分别达到20.73%、67.82%、72.56%。因此,MFC作为产生电能的新方法,在联合处理沼液等有机废水节能减排方面具有广阔前景。     

微生物燃料电池处理偶氮含盐废水的产电性能和降解过程

偶氮含盐废水生化处理流程复杂、电耗高,且降解机理尚不明确。本研究基于酸性重铬酸钾法水热处理获取改性阳极,进而构建微生物燃料电池（microbial fuel cell,MFC）对偶氮含盐废水进行处理。考察了不同二价阴离子对MFC产电性能和降解有机物效果的影响,并探究了MFC对直接红13的降解机理。结果表明,偶氮含盐废水中含有硫酸钠时的产电性能高于含有碳酸钠的情况,MFC最大功率密度为265.38mW/m²、最大电流密度为1.10A/m²;MFC处理偶氮含盐废水时,对直接红13的去除率低于无额外添加盐时的效果（71.13%）,对葡萄糖共基质的降解影响程度为：添加硫酸钠>添加碳酸钠>无额外添加盐。微生物群落和降解产物分析表明,MFC阳极生物膜通过变形菌门、拟杆菌门等微生物的协同作用实现了对直接红13的生物电化学降解,产电下降解产物以还原产物芳香胺为主。     

基于MES的CO2减排与高价值有机物转化研究进展

微生物电化学系统（MES）是一种可选择的CO₂减排利器,能够在降解温室效应的同时将CO₂转化为高价值有机物,解决CO₂的能源与资源化问题,因此受到了极大关注。MES系统是一种电驱动的生物电化学电子转移系统,可驱动CO₂转化为高价值C₁～C_n有机物。电活性微生物（EAB）的胞外电子传递效率是提高MES转化效率的关键因素。因此,探索解析电活性微生物胞外电子转移规律和转化过程的影响因素,有望揭示MES的微观机理,提高MES的转化效率,突破MES商业化发展瓶颈。     

Comparison of real‐time methods for maximizing power output in microbial fuel cells

Microbial fuel cells (MFCs) constitute a novel power generation technology that converts organic waste to electrical energy using microbially catalyzed electrochemical reactions. Since the power output of MFCs changes considerably with varying operating conditions, the online optimization of electrical load (i.e., external resistance) is extremely important for maintaining a stable MFC performance. The application of several real‐time optimization methods is presented, such as the perturbation and observation method, the gradient method, and the recently proposed multiunit method, for maximizing power output of MFCs by varying the external resistance. Experiments were carried out in two similar MFCs fed with acetate. Variations in substrate concentration and temperature were introduced to study the performance of each optimization method in the face of disturbances unknown to the algorithms. Experimental results were used to discuss advantages and limitations of each optimization method. © 2010 American Institute of Chemical Engineers AIChE J, 2010     

Inocula selection in microbial fuel cells based on anodic biofilm abundance of Geobacter sulfurreducens

Microbial fuel cells(MFCs)rely on microbial conversion of organic substrates to electricity.The optimal performance depends on the establishment of a microbial community rich in electrogenic bacteria.Usually this microbial community is established from inoculation of the MFC anode chamber with naturally occurring mixed inocula.In this study,the electrochemical performance of MFCs and microbial community evolution were evaluated for three inocula including domestic wastewater(DW),lake sediment(LS)and biogas sludge(BS)with varying substrate loading(L_(sub))and external resistance(R_(ext))on the MFC.The electrogenic bacterium Geobacter sulfurreducens was identified in all inocula and its abundance during MFC operation was positively linked to the MFC performance.The LS inoculated MFCs showed highest abundance(18% ± 1%)of G.sulfurreducens,maximum current density [I_(max)=(690 ± 30)m A·m~(-2)] and coulombic efficiency(CE = 29% ± 1%)with acetate as the substrate.Imaxand CE increased to(1780 ± 30)m A·m~(-2)and 58% ± 1%,respectively,after decreasing the R_(ext) from 1000 Ω to 200 Ω,which also correlated to a higher abundance of G.sulfurreducens(21% ± 0.7%)on the MFC anodic biofilm.The data obtained contribute to understanding the microbial community response to Lsub and R_(ext)for optimizing electricity generation in MFCs.     

Microbial fuel cells come of age

OVERVIEW: Microbial fuel cells (MFCs) are an emerging technology which directly converts chemical energy stored in organic matter to electricity. Driven by the increasing concern over the energy–climate crisis and environment pollution, MFCs have been developed rapidly in the past decade. Currently, MFCs are making the challenging step from laboratory to practical application. This paper focuses on MFC patents and the applications of MFCs. IMPACT: MFCs make it possible to directly exploit bio‐electricity from organic wastes with a higher energy transforming efficiency than other traditional technologies. The wide application of MFCs will significantly reduce the energy dependence on fossil fuel as well as the relative problems of climate and environmental pollution. APPLICATIONS: MFCs have been deployed in various practical environments, such as wastewater treatment plants, seafloor, etc. The electricity generated by MFCs has been used to charge low power devices. More applications have been funded or are to be undertaken. The successful pilot applications of MFCs promise a bright future for this technology. Copyright © 2011 Society of Chemical Industry     

Biocatalytic electrode improvement strategies in microbial fuel cell systems

Microbial fuel cells (MFCs) produce electricity as a result of the microbial metabolism of organic substrates, hence they represent a sustainable approach for energy production and waste treatment. If the technology is to be implemented in industry, low cost and sustainable bioelectrodes must be developed to increase power output, increase waste treatment capacity, and improve service intervals. Although the current application of abiotic electrode catalysts, such as platinum and electrode binders such as Nafion leads to greater MFC performance, their use is cost prohibitive. Novel bioelectrodes which use cost effective and sustainable materials are being developed. These electrodes are developed with the intention to reduce start-up time, reduce costs, extend life-span and improve core MFC performance metrics (i.e. power density, current density, chemical oxygen demand (COD) reduction and Coulombic efficiency (CE)). Comparison of different MFC systems is not an easy task. This is due to variations in MFC design, construction, operation, and different inocula (in the case of mixed-culture MFCs). This high intra-system variability should be considered when assessing MFC data, operation and performance. This review article examines the major issues surrounding bioanode and biocathode improvement in different MFC systems, with the ultimate goal of streamlining and standardising improvement processes. © 2018 Society of Chemical Industry     

Effects of a transient external voltage application on the bioanode performance of microbial fuel cells

The effects of a transient external voltage application on the bioanode performance of microbial fuel cells (MFCs) inoculated with mixed cultures were investigated. Different positive and negative external voltages were applied to a set of bioanodes. The MFCs under +1, −1, and −5 V voltage applications achieved higher current densities than the control during the start-up period. The MFC exposed to a voltage of +1 V had the highest maximum power density of 73.5 mW m⁻² after a 96-h operation. However, the +5 and +10 V voltage applications delayed or even deteriorated the MFC start-up. The −10 V voltage application initially induced a higher power output, but later had a detrimental effect on the MFC performance. The negative voltage application was proven to enhance the catalytic activity of the bioanode, and found to be partially responsible for the improved MFC bioanode performance.     

微生物燃料电池中碳材料改性阳极和碳基复合材料阳极的最新研究进展

微生物燃料电池(MFC)是一种利用微生物的代谢作用将化学能转化为电能的新技术,近年来受到广泛关注。文章综述了MFC阳极碳材料改性和优化的最新研究成果,介绍了碳材料改性阳极和碳基复合材料阳极的种类、理化特性、产电性能及其在MFC中的应用。     

土壤微生物燃料电池的研究进展及展望

微生物燃料电池（microbial fuel cells,MFCs）是一种利用产电微生物将化学能直接转化为电能的技术,其在运行期间不消耗外界能量且无二次污染,日益得到人们的广泛关注。土壤因富含有机质和庞大的微生物种群,是产电微生物的“天然培养基”。近几年来,以土壤为基质的MFCs在产电、土壤污染评价和修复等方面展现了较大的研究潜能和应用前景。本文全面介绍了目前MFCs在土壤产电、有机污染物降解、重金属污染治理、温室气体减排以及生物传感器等方面的应用研究;总结了目前土壤MFCs研究中应用的反应器构型、电极和产电微生物种群;在此基础上提出了以土壤为基质的MFCs在研究及应用过程中存在的主要问题,并对其研究前景进行展望。     

厌氧活性污泥产电特性及产电过程微生物群落变化

以厌氧活性污泥为接种液构建微生物燃料电池(MFC),检测了运行第1周期前后电池的理化性质及菌群变化情况。结果表明,MFC启动后产电性能良好,外接1000 Ω电阻时输出电压可达0.62 V,功率密度达1247 mW/m2,内阻为143 Ω, 化学需氧量(COD)去除率达63.6%;高通量测序结果显示,MFC菌群与原始接种厌氧活性污泥菌群相比变化较明显,菌群多样性指数降低,优势菌门硬壁菌门(Firmicutes)和变形菌门(Proteobacteria)为产电菌群常见门,与MFC产电能力直接相关的克雷伯氏菌属(Klebsiella)富集并成为优势菌属,相对丰度达16.73%。     

Microbial Power‐Generating Capabilities on Micro‐/Nano‐Structured Anodes in Micro‐Sized Microbial Fuel Cells

Microbial fuel cells (MFCs) are an alternative electricity generating technology and efficient method for removing organic material from wastewater. Their low power densities, however, hinder practical applications. A primary limitation in these systems is the anode. The chemical makeup and surface area of the anode influences bacterial respiration rates and in turn, electricity generation. Some of the highest power densities have been reported using large surface area anodes, but due to variable chemical/physical factors (e.g., solution chemistry, architecture) among these studies, meaningful comparisons are difficult to make. In this work, we compare under identical conditions six micro/nano‐structured anodes in micro‐sized MFCs (47 μL). The six materials investigated include carbon nanotube (CNT), carbon nanofiber (CNF), gold/poly (ϵ‐caprolactone) microfiber (GPM), gold/poly(ϵ‐caprolactone) nanofiber (GPN), planar gold (PG), and conventional carbon paper (CP). The MFCs using three dimensional anode structures (CNT, CNF, GPM, and GPN) exhibited lower internal resistances than the macroscopic CP and two‐dimensional PG anodes. However, those novel anode materials suffered from major issues such as high activation loss and instability for long‐term operation, causing an enduring problem in creating widespread commercial MFC applications. The reported work provides an in‐depth understanding of the interplay between micro‐/nano‐structured anodes and active microbial biofilm, suggesting future directions of those novel anode materials for MFC technologies.     

Generation behavior of elctricity in a microbial fuel cell

Electricity generation using a microbial fuel cell (MFC) was investigated with acetate as the fuel and Geobacter sulfurreducens as the biocatalyst on the anode electrode. The voltage and power density behaviors at various external resistances were observed, as were the coulombic efficiency and energy recovery behaviors at various acetate concentrations. A high voltage production was obtained when the pH in the cathode chamber was maintained in the range of 7–8, which is similar to that used in other MFC studies. After 72 hours of operation, the voltage production was decreased by 11.5% with 30 mM tris-HCl and by 33.7% with 10 mM tris-HCl.