Power production and purifying wastewater using UltraViolet-visible light powered single-chamber MFC(Microbial fuel cell)

김화평,인수일 한국공업화학회 2018 한국공업화학회 연구논문 초록집 Vol.2018 No.0

A novel hybrid single chamber microbial fuel cell is described in which a TiO2 nanotube array (TNT) photoanode is coupled with a conventional bioanode to achieve simultaneous degradation of methylene blue (MB) dye with improved power generation. As compared to a conventional microbial fuel cell (MFC), the described hybrid-MFC exhibits enhanced power density (14%), current density (33%), and voltage (4%) while simultaneously degrading MB dye, 82.79% after 3.5 h of operation under simulated solar light illumination. The key factor attributed to the enhanced performance is the addition of photogenerated electrons to the MFC external circuit. The effect of various design configurations is also investigated, such as the presence of an air cathode, anode type, and illumination. The hybrid-MFC strategy provides new directions for productive and economical utilization of microbial fuel cells.

환원전극 DO 농도에 따른 단일 및 직렬연결 미생물연료전지 전기발생량 평가

유재철(Jae Cheul Yu),이태호(Tae Ho Lee) 大韓環境工學會 2009 대한환경공학회지 Vol.31 No.4

미생물연료전지(Microbial fuel cell, MFC)의 효율은 산화전극부내의 유기물 산화율, 전기활성박테리아에 의한 전자 전달, 수소이온 전달, 환원전극내의 전자수용체의 농도 및 환원율, 내부저항 등 다양한 요소에 영향을 받는다. 특히 산소를 전자수용체로 이용하는 MFC의 경우, 환원전극내 산소농도는 MFC의 제한요소로 작용한다고 알려져 있다. 한편 MFC의 전기발생량을 높이기 위하여 여러 개의 MFC를 직렬 또는 병렬로 연결하여 전기발생량을 높이는 다양한 방법들이 연구되고 있다. 본 연구에서는 acetate를 산화전극부의 기질로 이용하고 산소를 환원전극의 전자수용체로 이용하는 단일 MFC와 직렬연결 MFC에서 환원전극의 용존산소 농도의 변화가 MFC 효율에 미치는 영향을 평가하였다. 단일 MFC의 전력밀도값(W/m3)은 DO 5>3>7>9 mg/L으로 나타났으며, 최대전력밀도값은 42 W/m3으로 나타났다. 직렬연결 MFC의 전력밀도값은 DO 5>7>9>3 mg/L으로 나타났으며, 최대전력밀도값은 20 W/m3이었다. 이러한 결과로부터 환원전극의 DO 농도는 MFC 설계 및 운전시에 중요한 제어인자로 고려해야 될 것으로 판단되었다. 또한 본 연구에서는 직렬연결 MFC의 운전 시, 일부 MFC에서 염의 축적으로 인한 전위역전 현상이 발생하여 전체 전기발생량이 감소하는 것을 확인할 수 있었다. 따라서 전기생산량을 높이기 위하여 MFC를 직렬로 연결하는 것보다 병렬로 연결하는 것이 보다 타당한 것으로 사료되었다. The performance of microbial fuel cell (MFC) can be affected by many factors including the rate of organic matter oxidation, the electron transfer to electrode by electrochemical bacteria, proton diffusion, the concentration of electron acceptor, the rate of electron acceptor reduction and internal resistance. the performance of MFC using oxygen as electron acceptor can be influenced by oxygen concentration as limit factors in cathode compartment. Many studies have been performed to enhance electricity production from MFC. The series or parallel stacked MFC connected several MFC units can use to increase voltages and currents produced from MFCs. In this study, a single MFC (S-MFC) and a stacked MFC (ST-MFC) using acetate as electron donor and oxygen as electron acceptor were used to investigate the influence of dissolved oxygen (DO) concentrations in cathode compartment on MFC performance. The power density (W/m3) of S-MFC was in order DO 5>3>7>9 mg/L, the maximum power density (W/m3) of S-MFC was 42 W/m3 at DO 5 mg/L. The power density (W/m3) of ST-MFC was in order DO 5>7>9>3 mg/L and the maximum power density (W/m3) of ST- MFC was 20 W/m3 at DO 5 mg/L. These results suggest that the DO concentration of cathode chamber should be considered as important limit factor of MFC operation and design for stacked MFC as well as single MFC. The results of ST-MFC operation showed the voltage decrease of some MFC units by salt formation on the surface of anode, resulting in decrease total voltage of ST-MFC. Therefore, connecting MFC units in parallel might be more appropriate way than series connections to enhance power production of stacked MFC.

가축분뇨를 이용한 미생물연료전지내 미생물군집의 탄소 기질 이용도에 관한 연구

장재경,홍선화,이미향,유영선,장인섭,김종구,강연구,이은영 한국폐기물자원순환학회 2012 한국폐기물자원순환학회지 Vol.29 No.8

This study was attempted to evaluate the change of microbial community in inoculums, lag, and stationary phase using the community level physiological profiles (CLPP) base on C-substrate utilization. It was to ascertain the characterizing microbial community over time in the enrichment step of microbial fuel cells. Microbial fuel cell is a device that converts chemical energy to electricity with aid of the catalytic reaction of microorganisms using C-substrate included wastewater. Microbial fuel cells enriched by a mixture of anaerobic digestive sludge of the sewage treatment plant and livestock wastewater were used. The current after enrichment was generated about 0.84 ± 0.06 mA. Microbial community in inoculums, lag and stationary phase used amine group, phosphorylated chemical group, and carboxylic acid group (some exclusion). However, phenolic compound did not use by microorganisms in lag and stationary phase. It means that there are not the microorganisms capable of decompose the phenol in microbial fuel cell enriched by livestock wastewater. In case of substrates of amino acid and carbohydrates group, these C-substrates were only used by microorganisms in the stationary phase. It may be that electrochemically active microorganisms (EAM) which we want to know should utilize the better these C-substrates than that of lag phase. This study showed that the electrochemically active bacteria that can be distinguished by electron changes of C-substrate utilization over time could be separated.

미생물연료전지가 전력생산에 영향을 미치는 요인들에 대한 상호관계 분석

이송근(Song-Keun Lee),김일주(Il-Ju Kim),이규화(Kyu-Hwa Lee),유규선(Kyu-Seon Yoo),송영채(Young-Chae Song) 한국조명·전기설비학회 2009 조명·전기설비학회논문지 Vol.23 No.12

미생물 연료전지(MFC: Microbial Fuel Cell)는 미생물을 사용하여 유기물의 산화에서 전기를 일으키는 장치이다. 현재 MFC는 많은 곳에서 연구되고 있으며 신재생 에너지로도 많은 관심을 받고 있다. 기존의 연구에서는 전력생산에 영향을 미치는 각각의 요인에 관련된 연구가 많이 진행되었으나, 요인들의 상호관계에 관한 연구는 많지 않았다. 본 논문에서는 기존의 MFC를 개선하기 위해 전력의 생산을 좌우하는 요인을 조사하였으며, 요인들의 상호관계를 효율적으로 증명하기 위해 새로운 반응조를 제작하였다. 실험을 통해 얻어진 데이터를 기초로 MFC에서 전력생산에 영향을 미치는 요인들을 분석하였으며 이를 바탕으로 하폐수처리 시스템에 MFC를 적용하여 하폐수처리 및 전력을 생산한다는 새로운 개념의 에너지생산 하폐수처리 시스템을 제안하였다. Microbial fuel cell (MFC) is a device to produce a electricity from the oxidation of organic materials using microorganism. Recently many researchers have been studying MFC which is focused as regeneration energy source. Previews studies have focused every each factor that influence the production of electric power. However they didn't study a lot about the correlation among the factors. In order to improve the MFC, we analysed the factors which influencing the generation of electric power of MFC. Also, we made a new compartment to verify the correlations among the factors efficiently. Based on the result obtained from the experiments in the laboratory, we analysed the factors and we suggested a new concept of waste water treatment system to produce electrical energy during the treatment of waste water.

스텐철사를 전극으로 이용하는 미생물연료전지의 전류 발생

장재경(Jae Kyung Jang),김경민(Kyung Min Kim),변성아(Sungah Byun),유영선(Young Sun Ryou),장인섭(In Seop Chang),강연구(Young Koo Kang),김영화(Young Hwa Kim) 大韓環境工學會 2014 대한환경공학회지 Vol.36 No.11

산화전극부 전극은 단순히 전자를 받아 전달할 수 있는 역할 뿐만 아니라 공극이 많아 표면적이 큰 구조로 미생물을고정화할 수 있는 표면적을 제공할 수 있어야 한다. 미생물의 수가 많을수록 폐수처리 효율과 전류발생을 높일 수 있기 때문이다. 따라서 전극은 미생물연료전지의 효율을 높일 수 있는 중요한 역할을 하는 인자 중의 하나이다. 본 연구는 미생물연료전지에 사용하는 고가의 흑연펠트를 스텐철사 타래(철 수세미)로 대체할 수 있는지 알아보기 위한 것이다. 이 연구에 사용된가축분뇨는 전처리를 거친 후 유기오염물질(COD)로 500 mg/L로 희석한 것을 이용하였고, 이때 전류 발생은 스텐철사 타래를 적용하였을 때 약 5% 정도 낮았지만 큰 차이가 없는 것으로 나타났다. 유기오염물질(COD)의 감소는 스텐철사 타래를 이용하였을 때 88.3%이었으며, 흑연펠트를 사용하였을 때 82.4%로 스텐철사 타래의 제거율이 더 높게 나타났다. 암모니아성질소 이온의 경우는 두 경우 모두 반응시간에 따라 농도 변화가 거의 없는 것으로 나타났다. 이 결과 스텐철사 타래를 적용하였을 때 전류발생이나 수처리 측면 모두 효과가 유사하거나 더 좋은 결과를 보였으며, 초기 시스템을 구축하는 비용을 약1/50 정도로 줄일 수 있는 것으로 예상되어. 흑연펠트 대체제로 적용이 가능할 것으로 판단된다. Anode electrode in a microbial fuel cell (MFC) should transfer the receiving electron as well as provide large surfacearea that can be immobilized microorganisms. Microorganisms’ population is one of important factors to improve the currentgeneration and to treat the livestock wastewater by biological treatment. These studies were attempted to investigate if stainless-steelwire skein (SSWS) could be used as anode electrode replacement a graphite felt electrode in microbial fuel cell. For these studies,pretreated livestock wastewater was used diluted to 500 mg/L as COD before use. At this time, the current showed a little differenceof about 5% when using each of a SSW and graphite felt (control). There was no significant difference in the current value. Theorganic removal rate in the microbial fuel cells used graphite felt and SSWS was 82.4% and 88.3%, respectively. The COD removalin the MFC used the SSWS was higher than that of graphite felt. Ammonium nitrogen was showed similar trend in two case all. These results about current generation and organic matter reduction seem possible that SSWS was used to anode electrode. WhenSSWS is used, the initial investment for system construction is expected to be able to reduce by approximately 1/50.

Comparison in performance of sediment microbial fuel cells according to depth of embedded anode

An, J.,Kim, B.,Nam, J.,Ng, H.Y.,Chang, I.S. Elsevier Applied Science 2013 Bioresource technology Vol.127 No.-

Five rigid graphite plates were embedded in evenly divided sections of sediment, ranging from 2cm (A1) to 10cm (A5) below the top sediment layer. The maximum power and current of the MFCs increased in depth order; however, despite the increase in the internal resistance, the power and current density of the A5 MFC were 2.2 and 3.5times higher, respectively, than those of the A1 MFC. In addition, the anode open circuit potentials (OCPs) of the sediment microbial fuel cells (SMFCs) became more negative with sediment depth. Based on these results, it could be then concluded that as the anode-embedding depth increases, that the anode environment is thermodynamically and kinetically favorable to anodophiles or electrophiles. Therefore, the anode-embedding depth should be considered an important parameter that determines the performance of SMFCs, and we posit that the anode potential could be one indicator for selecting the anode-embedding depth.

미생물 농도에 따르는 Air-Cathode MFC의 전력발생과 유기물질제거 특성

김도영 ( Do Young Kim ),임종수 ( Bong Su Lim ),최찬수 ( Chan Soo Choi ),김대현 ( Dae Hyun Kim ) 한국물환경학회 2012 한국물환경학회지 Vol.28 No.6

In order to improve applicability of a microbial fuel cell the laboratory-scale study has been performed by adopting an air-cathode MFC system with high concentrated anaerobic slugies in this study. The concentrations of microbes are grouped into three types, Type A (TS 1.7%), Type B (TS 1.1%) and Type C (TS 0.51%). The open circuit voltage (Voc) characteristics showed that the medium microbes concentration of 1.10% (Type B) kept a constant voltage of 1.0 V for 150 hours, which showed the longest time among three types (Type A and Type C). The discharge charge curves for a closed circuit with 500 Ω also showed that Type B generated a stable discharge voltage of 0.8 V for a longer time as in the open circuit voltage case. This could be explained by the relatively large amount of the attached microbes. Under the Voc condition the COD removal efficiency of Type B was found to be low for a long time, but those of Type A and C were found to be high for a short period of time. Therefore, the suspended microbes could decrease the coulombic efficiency. It was concluded that the high Voc was caused by low COD and the Voc became low after the COD removal. The COD reduction resulted in an unstable and low working voltage. From the polarization characteristics Type A was found to show the highest power density of 193 mW/m2 with a fill factor of 0.127 due to the relatively high remaining COD even after the MFC reaction.

연속식 미생물연료전지 성능에 미치는 운전변수의 영향

정재우,최영대,이명은,송영채,우정희,유규선,이채영 대한상하수도학회 2013 상하수도학회지 Vol.27 No.4

Effects of operating parameters such as hydraulic retention time(HRT), recycle ratio and influent COD concentration on the performance of a continuous flow microbial fuel cell(MFC) were investigated. Decrease of HRT improved mass transfer of substrate to electrogenic microorganisms, therefore resulting in increased electrode voltage and power generation of MFC. Increase of HRT promoted COD removal by elongating retention time for COD removal in MFC. Recycling of effluent increased the COD removal and coulombic efficiencies by returning suspended microorganisms into MFC. Increase of influent COD enhanced COD removal due to the improved mass transfer of substrate. Decrease of coulombic efficiency by the increase of the HRT and influent COD concentration indicated that they enhanced the activities of fermentative bacteria.

Sediment에서의 전기활성 박테리아 분포 특성

손형식(Hyeng Sik Son),손희종(Hee Jong Son),김미아(Mia Kim),이상준(Sang Joon Lee) 大韓環境工學會 2010 대한환경공학회지 Vol.32 No.12

낙동강, 회동 및 기장에서 채집한 sediment의 미생물 군집을 FISH 분석을 통하여 조사한 결과, α 그룹, Acidobacter 그룹 및 Cyanobacter 그룹의 분포비율이 가장 높았으며 전체적으로 서로 유사한 분포 특성을 나타내었다. 각각의 sediment를 접종한 MFC 농화배양 이후의 coulombic yield는 낙동강, 회동 및 기장의 경우 각각 0.64 C, 0.50 C, 0.61 C로 나타났으며, 농화배양 완료 후의 미생물 군집분포는 β-Proteobacteria, γ-Proteobacteria, Acidobacter 그룹 및 Firmicutes 그룹이 농화배양 전보다 각각 45~90%, 50~90%, 40~80% 및 45~125% 정도 생체량이 증가한 것으로 나타났다. 농화배양이 끝난 후 16S rDNA를 이용한 미생물 동정결과에서, 낙동강 sediment를 주입한 MFC의 경우는 α-Proteobacteria의 속하는 Roseomonas sp., Azospillum sp.와 γ-Proteobacteria의 Frateuria sp., Dyella sp., Enterobacter sp.와 Deinococci 그룹의 Deinococcus sp.가 동정되었고, 기장 sediment는 α-Proteobacteria의 Azospillum sp.와 β-Proteobacteria의 Delftia sp., Ralstonia sp.와 γ-Proteobacteria의 Klebsiella sp.와 Deinococci 그룹의 Deinococcus sp.가 동정되었으며, 회동 sediment는 γ-Proteobacteria의 Pseudomonas sp., Klebsiella sp.와 Deinococci 그룹의 Deinococci sp.와 Actinobacteria 그룹의 Leifsonia sp.와 Bacilli 그룹의 Bacillus sp.가 동정되었다. Microbial fuel cells (MFC) were enriched using sediment Nakdong river, Hoidong river and protected water area in Gijang. The microbial community of sediment and enriched MFC was analyzed by FISH (fluorescent in situ hybridization) and 16S rDNA sequencing. α-Proteobacteria, Acidobacter and Cyanobactia group were dominant in sediment by FISH. The coulombs of the final 10 peak of the 3 MFC (Nakdong, Hoidong, Gijang) were 0.64 C, 0.50 C, 0.61 C, respectively. When MFCs were enriched by sediment, β-, γ-Proteobacteria, Acidobacter and Firmicutes group increased 45~90%, 50~90%, 40~80% and 45~125%, respectively. In results of 16S rDNA sequencing, Roseomonas sp., Azospillium sp., Frateuria sp., Dyella sp., Enterobacter sp. and Deinocossus were isolated from Nakdong river and Azospillium sp., Delftia sp., Ralstonia sp., Klebsiella sp. and Deinococcus sp. were isolated from protected water area in Gijang and Pseudomonas sp., Klebsiella sp., Deinococcus sp., Leifsonia sp. and Bacillus sp. were isolated from Hoidong river.

산화전극 결합제로서 나피온용액에 혼합된 에폭시가 미생물연료전지의 성능에 미치는 영향

송영채(Young Chae Song),김대섭(Dae Seop Kim),우정희(Jung Hui Woo) 大韓環境工學會 2014 대한환경공학회지 Vol.36 No.1

팽창흑연과 탄소나노튜브를 이용한 복합 산화전극을 나피온용액에 다양한 비율로 에폭시를 혼합한 결합제를 이용하여 제작하였으며, 산화전극 결합제에 함유된 에폭시량이 미생물연료전지의 성능에 미치는 영향을 회분식 실험을 통하여 조사하였다. 산화전극 결합제에 에폭시의 함량이 증가함에 따라 산화전극 구성 물질들의 물리적 부착력은 점차 증가하였으나, 활성화저항과 오옴저항의 증가로 인한 내부저항이 증가하였다. 산화전극 결합제로 에폭시를 혼합하지 않고 나피온용액 만을 사용한 대조구의 경우 1,892 mW/m2에 달하였으나 산화전극 결합제에 에폭시 함량이 증가함에 따라 미생물연료전지의 최대전력밀도는 점차 감소하였다. 산화전극 결합제에 에폭시함량이 50%일 때 최대전력밀도는 1,425 mW/m2로서 대조구의 75.3%까지 감소하였으나, 고가의 나피온용액 사용량을 감소시키고 산화전극 결합제의 물리적 부착력을 높일 수 있다는 측면에서 고려할 때 나피온용액과 에폭시를 같은 비율로 혼합한 물질은 산화전극결합제로서의 좋은 대안이 될 수 있는 것으로 판단된다. The composite anodes of exfoliated graphite (EG) and multiwall carbon nanotube (MWCNT) were fabricated by using the binders with different content of epoxy in Nafion solution. The influence of the epoxy content in the anode binder on the performance of microbial fuel cell (MFC) was examined in a batch reactor. With the increase in the epoxy content in the anode binder, increase in physical binding force was observed, but at the same time an increase in the internal resistance of MFC was also observed. This was due to the increase in activation and ohmic resistance. For the anode binder without epoxy, the maximum power density was 1,892 mW/m2, but a decrease in maximum power density was observed with the increase in the epoxy content in the anode binder. With the epoxy content of 50% in the anode binder, a decrease in the maximum power density to 1,425 mW/m2 was observed, which about 75.3% of the anode binder without epoxy is. However, the material consisting of the same amount of epoxy and Nafion solution is a good alternative for anode binder in terms of durability and economics of MFC.