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Shin C, Bae J, McCarty PL. Lower operational limits to volatile fatty acid degradation with dilute wastewaters in an anaerobic fluidized bed reactor. BIORESOURCE TECHNOLOGY 2012; 109:13-20. [PMID: 22285295 DOI: 10.1016/j.biortech.2012.01.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 01/03/2012] [Accepted: 01/04/2012] [Indexed: 05/31/2023]
Abstract
A general concern that anaerobic treatment of dilute wastewaters is limited by the inability of methanogenic and related syntrophic organisms to reduce substrate concentrations adequately was evaluated using a 35 °C granular activated carbon-containing laboratory-scale fluidized bed reactor fed an acetate-propionate equal chemical oxygen demand (COD) mixture synthetic wastewater. Contrary to general expectations, effluent acetate and propionate concentrations remained near or below their detection limits of 0.4 mg COD/L with influent COD of 200mg/L, 17 min hydraulic retention time, and organic loading as high as 17 kg COD/m(3)d, or with influent COD values ranging from 45 to 2010 mg COD/L and organic loadings of 4.2-4.5 kg COD/m(3)d. The effluent acetate concentrations in these well-fed systems were at or much below reported threshold limits for starving non-fed cultures, suggesting that a better understanding of threshold values and factors affecting treatment efficiency with anaerobic treatment of dilute wastewaters is needed.
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Affiliation(s)
- Chungheon Shin
- Department of Environmental Engineering, Inha University, Namgu, Yonghyun dong 253, Incheon, Republic of Korea
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52
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Farajzadehha S, Mirbagheri S, Farajzadehha S, Shayegan J. Lab Scale Study of HRT and OLR Optimization in UASB Reactor for Pretreating Fortified Wastewater in Various Operational Temperatures. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.apcbee.2012.03.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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53
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El-Gohary F, El-Kamah H, Abdel Wahaab R, Mahmoud M, Ibrahim HA. Management of wastewater from the vegetable dehydration industry in Egypt--a case study. ENVIRONMENTAL TECHNOLOGY 2012; 33:211-219. [PMID: 22519105 DOI: 10.1080/09593330.2011.559276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Management of wastewater from the vegetable dehydration industry was the subject of this study. A continuous monitoring programme for wastewater was carried out for almost four months. The characterization of the wastewater indicated that the vegetable dehydration wastewater contains moderate concentrations of organics, solids and nutrients. The wastewater was subjected to three different treatment processes, namely aerobic treatment, anaerobic treatment and chemical coagulation-flocculation treatment. For aerobic treatment, the removal of chemical oxygen demand (COD), biochemical oxygen demand (BOD5) and total suspended solids (TSS) was accomplished within 5 h, and no further reduction was observed after that, with the steady state COD and BOD5 removal efficiencies being 95% +/- 10% and 97% +/- 8%, respectively. For anaerobic treatment, the removal efficiencies for COD, BOD5 and TSS were 67-81%, 70-86% and 56-69%, respectively at hydraulic retention times (HRTs) of 5, 6 and 8 h. Chemical coagulation-flocculation treatment also achieved good results. The COD removal efficiency was 72%, 51% and 75% for ferric chloride (56 g/m3 of wastewater), lime (140 g/m3 of wastewater) and ferric chloride aided with lime (100 g/m3 for ferric chloride and 200 g/m3 for lime), respectively. The corresponding TSS removal values were 92% +/- 17%, 20% +/- 7% and 93% +/- 9%. Based on the available results and the seasonally operated mode of this industry in Egypt, the chemical coagulation-flocculation process is therefore considered to be moste applicable from a technical point of view and for the simplicity of operation and maintenance.
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Affiliation(s)
- Fatma El-Gohary
- Water Pollution Research Department, National Research Centre, El-Tahrir Street, Cairo, Egypt
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54
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Hazrati H, Shayegan J. Upgrading activated sludge systems and reduction in excess sludge. BIORESOURCE TECHNOLOGY 2011; 102:10327-10333. [PMID: 21940165 DOI: 10.1016/j.biortech.2011.08.112] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2011] [Revised: 08/24/2011] [Accepted: 08/26/2011] [Indexed: 05/31/2023]
Abstract
Most of 200 Activated Sludge Plant in Iran are overloaded and as a result, their efficiency is low. In this work, a pilot plant is manufactured and put into operation in one of the wastewater treatment plants in the west of Tehran. Instead of conventional activated sludge, a membrane bioreactor and an upflow anaerobic sludge blanket reactor used as a pretreatment unit in this pilot. For the sake of data accuracy and precision, an enriched municipal wastewater was opted as an influent to the pilot. Based on the attained result, the optimum retention time in this system was 4h, and the overall COD removal efficiency was 98%. As a whole, the application of this retrofit would increase the plant's capacity by a factor of 5 and reducing the excess sludge by a factor of 10. The sludge volume index in the anaerobic reactor was about 12 after granulation occurred.
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Affiliation(s)
- Hossein Hazrati
- Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran
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55
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Diversity and enrichment of nitrite-dependent anaerobic methane oxidizing bacteria from wastewater sludge. Appl Microbiol Biotechnol 2011; 92:845-54. [PMID: 21667086 PMCID: PMC3198195 DOI: 10.1007/s00253-011-3361-9] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 04/29/2011] [Accepted: 04/30/2011] [Indexed: 11/23/2022]
Abstract
Recently discovered microorganisms affiliated to the bacterial phylum NC10, named “Candidatus Methylomirabilis oxyfera”, perform nitrite-dependent anaerobic methane oxidation. These microorganisms could be important players in a novel way of anaerobic wastewater treatment where ammonium and residual dissolved methane might be removed at the expense of nitrate or nitrite. To find suitable inocula for reactor startup, ten selected wastewater treatment plants (WWTPs) located in The Netherlands were screened for the endogenous presence of M. oxyfera using molecular diagnostic methods. We could identify NC10 bacteria with 98% similarity to M. oxyfera in nine out of ten WWTPs tested. Sludge from one selected WWTP was used to start a new enrichment culture of NC10 bacteria. This enrichment was monitored using specific pmoA primers and M. oxyfera cells were visualized with fluorescence oligonucleotide probes. After 112 days, the enrichment consumed up to 0.4 mM NO2− per day. The results of this study show that appropriate sources of biomass, enrichment strategies, and diagnostic tools existed to start and monitor pilot scale tests for the implementation of nitrite-dependent methane oxidation in wastewater treatment at ambient temperature.
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56
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Rao PV, Baral SS. Attribute based specification, comparison and selection of feed stock for anaerobic digestion using MADM approach. JOURNAL OF HAZARDOUS MATERIALS 2011; 186:2009-2016. [PMID: 21247688 DOI: 10.1016/j.jhazmat.2010.12.108] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2010] [Revised: 11/19/2010] [Accepted: 12/21/2010] [Indexed: 05/30/2023]
Abstract
Organic wastes are common in nature and generated at different sources which need to be treated before disposing into the environment. Anaerobic digestion (AD) process is a primary technique used for digestion and reduction of the ill effects of disposing the organic waste. Selection of appropriate feed stock for anaerobic digestion among the available options is a primary concern and the process efficiency and stability largely depend on this. The present paper describes a methodology for evaluation, comparison, ranking and optimum selection of a feed stock for anaerobic digestion. A 30 attribute coding scheme is proposed to evaluate the existing alternatives for feed stock of anaerobic digester. A three stage procedure which includes the elimination search is proposed to evaluate the available alternatives with the help of attributes quickly. Technique for order preference by similarity to ideal solution (TOPSIS) is a Multiple Attribute Decision Making (MADM) approach and graphical methods namely line graph and spider diagrams are used for optimum selection of feed stock among the available options. MATLAB code is written to execute the three stage procedure. The proposed methodology is explained through an illustrated example.
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Affiliation(s)
- P Venkateswara Rao
- Chemical Engineering Group, Birla Institute of Technology and Science, Pilani-K.K. Birla Goa Campus, Zuari Nagar, Goa 403726, India
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57
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Siles JA, Brekelmans J, Martín MA, Chica AF, Martín A. Impact of ammonia and sulphate concentration on thermophilic anaerobic digestion. BIORESOURCE TECHNOLOGY 2010; 101:9040-9048. [PMID: 20674337 DOI: 10.1016/j.biortech.2010.06.163] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2010] [Revised: 06/28/2010] [Accepted: 06/30/2010] [Indexed: 05/29/2023]
Abstract
The effect of increasing concentrations of ammonia and sulphate on thermophilic anaerobic digestion (52 degrees C) was studied at laboratory-scale. The substrate consisted of a synthetic solution supplemented with ammonia and sodium sulphate. In terms of biogas production, the results showed that the C/N and C/SO(4)(2-) thresholds were 4.40 and 1.60, respectively, corresponding to 620 mg FA (free ammonia)/L and 1400 mg SO(4)(2-)/L. No reduction in biogas production was observed until reaching the above concentration of sulphate in the sulphate toxicity test. However, when the concentration of ammonia was increased to 620 mg FA/L in the ammonia toxicity test, a gradual decrease of 21% was observed for the biogas. In order to characterise each set of experiments kinetically, a biogas production first-order kinetic model was used to fit the experimental data. The proposed model accurately predicted the behaviour of the microorganisms affecting the thermophilic anaerobic digestion, allowing its evolution to be predicted.
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Affiliation(s)
- J A Siles
- Departamento de Química Inorgánica e Ingeniería Química, Facultad de Ciencias, Universidad de Córdoba, Campus Universitario de Rabanales, Edificio C-3, Ctra. Madrid-Cádiz, km 396, 14071 Córdoba, Spain
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58
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59
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Tawfik A, Ohashi A, Harada H. Effect of sponge volume on the performance of down-flow hanging sponge system treating UASB reactor effluent. Bioprocess Biosyst Eng 2009; 33:779-85. [DOI: 10.1007/s00449-009-0399-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Accepted: 11/29/2009] [Indexed: 10/20/2022]
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60
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Briones AM, Daugherty BJ, Angenent LT, Rausch K, Tumbleson M, Raskin L. Characterization of microbial trophic structures of two anaerobic bioreactors processing sulfate-rich waste streams. WATER RESEARCH 2009; 43:4451-4460. [PMID: 19643455 DOI: 10.1016/j.watres.2009.07.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 05/20/2009] [Accepted: 07/04/2009] [Indexed: 05/28/2023]
Abstract
A multi-compartment anaerobic bioreactor, designated the anaerobic migrating blanket reactor (AMBR), did not perform well in terms of chemical oxygen demand (COD) removal after an increase in sulfate load, compared to a conventional upflow anaerobic sludge blanket (UASB) reactor. The trophic structures of the bioreactors were characterized by analyzing the electron flows, formation and consumption of fermentation intermediates and terminal product (methane and hydrogen sulfide) formation. Critical performance parameters were linked to operational perturbations such as increase in sulfate load and changes in flow reversal schemes in the AMBR. Both of these manipulations affected the microbial communities, which were monitored by terminal restriction fragment length polymorphism (T-RFLP) analysis targeting the bacterial and archaeal domains. The less stable AMBR did not produce granular biomass, and in response to increased sulfate concentrations, experienced a reversal in the distribution of hydrogenotrophic methanogens that correlated with a shift in electron flow from butyrate to propionate. As this shift occurred, bacterial populations such as butyrate-producing clostridia, became predominant, thus leading to reactor imbalance. The stable UASB reactor developed and retained granules and maintained a relatively stable archaeal community. Sulfate perturbation led to the selection of a novel bacterial group (Thermotogaceae), which was most likely well adapted to the increasingly sulfidogenic conditions in the bioreactor.
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Affiliation(s)
- A M Briones
- Department of Civil and Environmental Engineering, University of Michigan, 1351 Beal Avenue, Ann Arbor, MI 48109-2125, USA
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61
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Treatment of domestic wastewater in an up-flow anaerobic sludge blanket reactor followed by moving bed biofilm reactor. Bioprocess Biosyst Eng 2009; 33:267-76. [DOI: 10.1007/s00449-009-0321-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2008] [Accepted: 04/14/2009] [Indexed: 10/20/2022]
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62
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Narihiro T, Terada T, Kikuchi K, Iguchi A, Ikeda M, Yamauchi T, Shiraishi K, Kamagata Y, Nakamura K, Sekiguchi Y. Comparative Analysis of Bacterial and Archaeal Communities in Methanogenic Sludge Granules from Upflow Anaerobic Sludge Blanket Reactors Treating Various Food-Processing, High-Strength Organic Wastewaters. Microbes Environ 2009; 24:88-96. [DOI: 10.1264/jsme2.me08561] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Takashi Narihiro
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Takeshi Terada
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST)
- Fujikasui Engineering Co., Ltd
| | | | - Akinori Iguchi
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST)
| | | | | | | | - Yoichi Kamagata
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST)
- Research Institute of Genome-based Biofactory, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Kazunori Nakamura
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Yuji Sekiguchi
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST)
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63
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Yiannopoulos AC, Manariotis ID, Chrysikopoulos CV. Design and analysis of a solar reactor for anaerobic wastewater treatment. BIORESOURCE TECHNOLOGY 2008; 99:7742-7749. [PMID: 18328695 DOI: 10.1016/j.biortech.2008.01.067] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Revised: 01/20/2008] [Accepted: 01/27/2008] [Indexed: 05/26/2023]
Abstract
The aim of this research was to design a solar heated reactor system to enhance the anaerobic treatment of wastewater or biological sludge at temperatures higher than the ambient air temperature. For the proposed reactor system, the solar energy absorbed by flat plate collectors was transferred to a heat storage tank, which continuously supplied an anaerobic-filter reactor with water at a maximum temperature of 35 degrees C. The packed reactor was a metallic cylindrical tank with a peripheral twin-wall enclosure. Inside this enclosure was circulated warm water from the heat storage tank. Furthermore, a mathematical model was developed for the prediction of the temperature distribution within the reactor under steady state conditions. Preliminary results based on model simulations performed with meteorological data from various geographical regions of the world suggested that the proposed solar reactor system could be a promising and environmentally friendly approach for anaerobic treatment of wastewater and biological sludge.
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Affiliation(s)
- Andreas Ch Yiannopoulos
- Department of Mechanical Engineering, Technological and Educational Institute of Patras, M. Alexandrou 1, 26334 Patras, Greece.
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64
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Mahmoud N. High strength sewage treatment in a UASB reactor and an integrated UASB-digester system. BIORESOURCE TECHNOLOGY 2008; 99:7531-7538. [PMID: 18372171 DOI: 10.1016/j.biortech.2008.02.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Revised: 02/13/2008] [Accepted: 02/14/2008] [Indexed: 05/26/2023]
Abstract
The treatment of high strength sewage was investigated in a one-stage upflow anaerobic sludge blanket (UASB) reactor and a UASB-digester system. The one-stage UASB reactor was operated in Palestine at a hydraulic retention time (HRT) of 10h and at ambient air temperature for a period of more than a year in order to asses the system response to the Mediterranean climatic seasonal temperature fluctuation. Afterwards, the one-stage UASB reactor was modified to a UASB-digester system by incorporating a digester operated at 35 degrees C. The achieved removal efficiencies in the one-stage UASB reactor for total, suspended, colloidal, dissolved and VFA COD were 54, 71, 34, 23%, and -7%, respectively during the first warm six months of the year, and achieved only 32% removal efficiency for COD total over the following cold six months of the year. The modification of the one-stage UASB reactor to a UASB-digester system had remarkably improved the UASB reactor performance as the UASB-digester achieved removal efficiencies for total, suspended, colloidal, dissolved and VFA COD of 72, 74, 74, 62 and 70%. Therefore, the anaerobic treatment of high strength sewage during the hot period in Palestine in a UASB-digester system is very promising.
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Affiliation(s)
- Nidal Mahmoud
- Institute of Environmental and Water Studies (IEWS), Birzeit University, P.O. Box 14, Birzeit, The West Bank, Palestine.
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65
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Gunawardena A, Fernando S, To F. Performance of a yeast-mediated biological fuel cell. Int J Mol Sci 2008; 9:1893-1907. [PMID: 19325724 PMCID: PMC2635613 DOI: 10.3390/ijms9101893] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Revised: 08/30/2008] [Accepted: 09/24/2008] [Indexed: 11/16/2022] Open
Abstract
Saccharomyces cerevisiae present in common Baker's yeast was used in a microbial fuel cell in which glucose was the carbon source. Methylene blue was used as the electronophore in the anode compartment, while potassium ferricyanide and methylene blue were tested as electron acceptors in the cathode compartment. Microbes in a mediator-free environment were used as the control. The experiment was performed in both open and closed circuit configurations under different loads ranging from 100 kOmega to 400Omega. The eukaryotic S. cerevisiae-based fuel cell showed improved performance when methylene blue and ferricyanide were used as electron mediators, rendering a maximum power generation of 146.71+/-7.7 mW/m(3). The fuel cell generated a maximum open circuit voltage of 383.6+/-1.5 mV and recorded a maximum efficiency of 28+/-1.8 % under 100 kOmega of external load.
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Affiliation(s)
- Anuradh Gunawardena
- Department of Biological and Agricultural Engineering, Texas A&M University, College Station, TX 77843, USA
| | - Sandun Fernando
- Department of Biological and Agricultural Engineering, Texas A&M University, College Station, TX 77843, USA
- *Author to whom correspondence should be addressed; E-Mail:
; Tel. +1-979-845-9793; Fax: +1-979-845-3932
| | - Filip To
- Department of Agricultural and Biological Engineering, Mississippi State University, MS 39762, USA
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66
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Liu Y, Whitman WB. Metabolic, phylogenetic, and ecological diversity of the methanogenic archaea. Ann N Y Acad Sci 2008; 1125:171-89. [PMID: 18378594 DOI: 10.1196/annals.1419.019] [Citation(s) in RCA: 626] [Impact Index Per Article: 39.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Although of limited metabolic diversity, methanogenic archaea or methanogens possess great phylogenetic and ecological diversity. Only three types of methanogenic pathways are known: CO(2)-reduction, methyl-group reduction, and the aceticlastic reaction. Cultured methanogens are grouped into five orders based upon their phylogeny and phenotypic properties. In addition, uncultured methanogens that may represent new orders are present in many environments. The ecology of methanogens highlights their complex interactions with other anaerobes and the physical and chemical factors controlling their function.
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Affiliation(s)
- Yuchen Liu
- Department of Microbiology, University of Georgia, 541 Biological Sciences Building, Athens, GA 30605, USA
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67
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Rozendal RA, Hamelers HVM, Rabaey K, Keller J, Buisman CJN. Towards practical implementation of bioelectrochemical wastewater treatment. Trends Biotechnol 2008; 26:450-9. [PMID: 18585807 DOI: 10.1016/j.tibtech.2008.04.008] [Citation(s) in RCA: 494] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Revised: 04/16/2008] [Accepted: 04/21/2008] [Indexed: 10/21/2022]
Abstract
Bioelectrochemical systems (BESs), such as microbial fuel cells (MFCs) and microbial electrolysis cells (MECs), are generally regarded as a promising future technology for the production of energy from organic material present in wastewaters. The current densities that can be generated with laboratory BESs now approach levels that come close to the requirements for practical applications. However, full-scale implementation of bioelectrochemical wastewater treatment is not straightforward because certain microbiological, technological and economic challenges need to be resolved that have not previously been encountered in any other wastewater treatment system. Here, we identify these challenges, provide an overview of their implications for the feasibility of bioelectrochemical wastewater treatment and explore the opportunities for future BESs.
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Affiliation(s)
- René A Rozendal
- Advanced Water Management Centre, The University of Queensland, St. Lucia, QLD 4072, Australia.
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68
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Narihiro T, Sekiguchi Y. Microbial communities in anaerobic digestion processes for waste and wastewater treatment: a microbiological update. Curr Opin Biotechnol 2007; 18:273-8. [PMID: 17462878 DOI: 10.1016/j.copbio.2007.04.003] [Citation(s) in RCA: 132] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2006] [Revised: 03/20/2007] [Accepted: 04/17/2007] [Indexed: 11/28/2022]
Abstract
Anaerobic digestion technology is the biological treatment of organic waste and wastewater without input of external electron acceptors (oxygen), offering the potential to reduce treatment cost and to produce energy as 'biogas' (methane) from organic waste. The technology has become enormously popular in the past two decades, and knowledge of microbiological aspects of the technology has also accumulated significantly. Major advances have been made in elucidating the diversity of yet-to-be cultured microbes in anaerobic digestion processes, and the cultivation of uncultured organisms is of great interest with regard to gaining insights into the function of these organisms. In addition, recent advances have been made in the development of microbial fuel cells as an alternative, direct energy-yielding treatment system.
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Affiliation(s)
- Takashi Narihiro
- Bio-Measurement Research Group, Institute for Biological Resources and Functions, National Institute of Advanced Science and Technology (AIST), AIST Tsukuba Central 6, Ibaraki 305-8566, Japan
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