Anaerobic Fluidized Bed Research Articles

Fuzzy control structure for an anaerobic fluidised bed

This article deals with the design of a fuzzy control strategy for a fluidised bed reactor, which is used for anaerobic wastewater treatment. This strategy is composed of a supervisor system and two PI L/A controllers. In addition, a biomass observer, designed on the basis of the Takagi–Sugeno approach considering a principal component analysis, is used with supervision proposals. The supervisor is also designed following the Takagi–Sugeno methodology; it detects the process state, selects and applies the most adequate control action in order to avoid the washout region. On the other side, two control actions are designed for bicarbonate regulation using the PI/LA technique: adding a base and dilution rate. These control actions, as well as the open loop operation, are selected by the supervisor in order to reject disturbances on the substrate influent allowing at the same time a high methane production. The applicability of the proposed structure in a fluidised bed reactor is illustrated via simulations.

Methane yield and microscopic observation as monitoring biofilm behaviour parameters, during start up phase of anaerobic inverse fluidized bed reactor

Anaerobic biofilm behavior on polyethylene and Extendosphere™ supports was evaluated during start-up of an inverse fluidized bed reactor using methane yield and microscopic observation as parameter monitoring techniques. Two anaerobic inverse fluidized bed reactors were used, one filled with triturated polyethylene as solid carrier material (diameter = 380 μm, density = 926 kg/m 3 ) and the other with Extendosphere™ (diameter = 147 μm, density = 700 kg/m 3 ). Each support material was used at up to 25% of its working volume (polyethylene = 1.2 l, Extendosphere™ = 1.9 l). Both reactors were started up in sequencing batch mode, applying organic loading rates of 0.5 to 14 g COD/l.d. Both supports exhibited rapid biofilm growth during start-up. Maximum surface colonization was 46% with the polyethylene and 100% with Extendosphere™. Both supports had a methane yield of 0.298 l CH 4 /g COD at 10 and 14 g COD/l.d, respectively. Digital microscopic observation results coincided with methane yield results, confirming each to be viable for parameter monitoring of biofilm growth. Data generated by these two techniques is different and complementary, and in conjunction they constitute a highly effective monitoring method of biofilm growth. Key words: Anaerobic digestion, biofilm, inverse fluidized bed reactor, methane yield.

Performance and composition of bacterial communities in anaerobic fluidized bed reactors for hydrogen production: Effects of organic loading rate and alkalinity

This study evaluated the effects of the organic loading rate (OLR) and pH buffer addition on hydrogen production in two anaerobic fluidized bed reactors (AFBRs) operated simultaneously. The AFBRs were fed with glucose, and expanded clay was used as support material. The reactors were operated at a temperature of 30 °C, without the addition of a buffer (AFBR1) and with the addition of a pH buffer (AFBR2, sodium bicarbonate) for OLRs ranging from 19.0 to 140.6 kg COD m−3 d−1 (COD: chemical oxygen demand). The maximum hydrogen yields for AFBR1 and AFBR2 were 2.45 and 1.90 mol H2 mol−1 glucose (OLR of 84.3 kg COD m−3 d−1), respectively. The highest hydrogen production rates were 0.95 and 0.76 L h−1 L−1 for AFBR1 and AFBR2 (OLR of 140.6 kg COD m−3 d−1), respectively. The operating conditions in AFBR1 favored the presence of such bacteria as Clostridium, while the bacteria in AFBR2 included Clostridium, Enterobacter, Klebsiella, Veillonellaceae, Chryseobacterium, Sporolactobacillus, and Burkholderiaceae.

Treatment of thin stillage in a high-rate anaerobic fluidized bed bioreactor (AFBR)

The primary objective of this work was to investigate the treatability of thin stillage as a by-product of bioethanol production plants using an anaerobic fluidized bed bioreactor (AFBR) employing zeolite with average diameter of (dm) of 425–610μm and specific surface area (SSA) of 26.5m2/g as the carrier media. Despite the very high strength of thin stillage with chemical oxygen demand of 130,000mgTCOD/L and suspended solids of 47,000mgTSS/L, the AFBR showed up to 88% TCOD and 78% TSS removal at very high organic and solids loading rates (OLR and SLR) of 29kg COD/m3d and 10.5kgTSS/m3d respectively and hydraulic retention time (HRT) of 3.5days. Methane production rates of up to 160L/d at the steady state equivalent to 40LCH4/Lthin stillaged and biogas production rate per reactor volume of 15.8Lgas/Lreactord were achieved.

High rate biological nutrient removal from high strength wastewater using anaerobic-circulating fluidized bed bioreactor (A-CFBBR)

Biological nutrient removal (BNR) from high strength wastewater was investigated using a newly developed integrated anaerobic fluidized bed (AF) with circulating fluidized bed bioreactor henceforth called A-CFBBR. The A-CFBBR showed 99.7%COD removal, 84% nitrogen removal, with a very low sludge yield of 0.017gVSS/gCOD while treating a synthetic wastewater containing 10,700mgCOD/L and 250mg NH3–N/L over a period of 6months. The system was operated at an organic loading rate (OLR) of 35kg COD/m3AFd and nitrogen loading rate (NLR) of 1.1kgN/m3CFBBR d at a hydraulic retention time (HRT) of less than 12h in the A-CFBBR. Microbial communities analysis using DGGE confirmed the presence of both AOBs and NOBs in the riser and downer. Pseudomonas putida and Pseudomonas fluorescence were the dominant denitrifiers present in the downer. Methanogenic activity was accomplished by a microbial mixture of archaea and bacteria in the anaerobic column.

Phenol degradation in an anaerobic fluidized bed reactor packed with low density support materials

Abstract - The objective of this research was to study phenol degradation in anaerobic fluidized bed reactors (AFBR) packed with polymeric particulate supports (polystyrene - PS, polyethylene terephthalate – PET, and polyvinyl chloride - PVC). The reactors were operated with a hydraulic retention time (HRT) of 24 h. The influent phenol concentration in the AFBR varied from 100 to 400 mg L -1 , resulting in phenol removal efficiencies of ~100%. The formation of extracellular polymeric substances yielded better results with the PVC particles; however, deformations in these particles proved detrimental to reactor operation. PS was found to be the best support for biomass attachment in an AFBR for phenol removal. The AFBR loaded with PS was operated to analyze the performance and stability for phenol removal at feed concentrations ranging from 50 to 500 mg L -1 . The phenol removal efficiency ranged from 90-100%. Keywords : Phenol; Anaerobic fluidized bed reactor; Biofilm; Polymeric particles.

Interrelationships between bioreactor volume, effluent recycle rate, temperature, pH, %H2, hydrogen productivity and hydrogen yield with undefined bacterial cultures

Simultaneous achievement of high volumetric productivities (HP=231.3mmolH2/L/h) and high hydrogen yields (HY=3.55molH2/mol glucose) was obtained by increasing the temperature to 70°C and by reducing the total bioreactor system volume (V) to 5.74L and increasing the degassed effluent recycle rate (Fer) to 3.2L/min, giving a V/Fer value of 1.8min. The bioprocess involved the recycling of degassed effluent at a high flow rate through a quasi-stationary fluidized granular bed. In this process the rate of physical removal of H2 trapped in the bulk liquid phase surrounding the fluidized granules reduced the thermodynamic constraints preventing the simultaneous achievement of high HPs and high HYs in the anaerobic fluidized granular bed bioreactor. Energy balance analysis showed that with heat recycling the bioreactor system could achieve a net positive volumetric energy output of 11.76W/L at an energy efficiency of 49.3%.

Lower operational limits to volatile fatty acid degradation with dilute wastewaters in an anaerobic fluidized bed reactor

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 0.4mg COD/L with influent COD of 200mg/L, 17min hydraulic retention time, and organic loading as high as 17kg COD/m3d, or with influent COD values ranging from 45 to 2010mg COD/L and organic loadings of 4.2–4.5kg COD/m3d. 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.

Effect of Substrate Concentration on Dark Fermentation Hydrogen Production Using an Anaerobic Fluidized Bed Reactor

The effect of substrate (glucose) concentration on the stability and yield of a continuous fermentative process that produces hydrogen was studied. Four anaerobic fluidized bed reactors (AFBRs) were operated with a hydraulic retention time (HRT) from 1 to 8 h and an influent glucose concentration from 2 to 25 g L(-1). The reactors were inoculated with thermally pre-treated anaerobic sludge and operated at a temperature of 30 °C with an influent pH around 5.5 and an effluent pH of about 3.5. The AFBRs with a HRT of 2 h and a feed strength of 2, 4, and 10 g L(-1) showed satisfactory H(2) production performance, but the reactor fed with 25 g L(-1) of glucose did not. The highest hydrogen yield value was obtained in the reactor with a glucose concentration of 2 g L(-1) when it was operated at a HRT of 2 h. The maximum hydrogen production rate value was achieved in the reactor with a HRT of 1 h and a feed strength of 10 g L(-1). The AFBRs operated with glucose concentrations of 2 and 4 g L(-1) produced greater amounts of acetic and butyric acids, while AFBRs with higher glucose concentrations produced a greater amount of solvents.

Continuous photo-hydrogen production in anaerobic fluidized bed photo-reactor with activated carbon fiber as carrier

Download options Please wait... Supplementary files Supplementary information PDF (59K) Article information DOI https://doi.org/10.1039/C2RA20420G Article type Communication Submitted 07 Mar 2012 Accepted 29 Apr 2012 First published 30 Apr 2012 Download Citation RSC Adv., 2012,2, 5531-5535 BibTex EndNote MEDLINE ProCite ReferenceManager RefWorks RIS Permissions Request permissions Continuous photo-hydrogen production in anaerobic fluidized bed photo-reactor with activated carbon fiber as carrier H. Ren, B. Liu, J. Ding, G. Xie, L. Zhao, D. Xing, W. Guo and N. Ren, RSC Adv., 2012, 2, 5531 DOI: 10.1039/C2RA20420G To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page. If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page. Read more about how to correctly acknowledge RSC content. Social activity Tweet Share Search articles by author Hong-Yu Ren Bing-Feng Liu Jie Ding Guo-Jun Xie Lei Zhao De-Feng Xing Wan-Qian Guo Nan-Qi Ren

Effect of Carrier Materials in Inverse Anaerobic Fluidized Bed Reactor for Treating High Strength Organic Waste Water

This article explains that thermo cool, plastic beads, cork, teak wood and perlite were tried as carrier materials in the lab-scale reactor towards treating high strength organic wastewater by using inverse anaerobic fluidized bed reactor (IAFBR). Organic wastewater of great strength (molasses) is pronounced for its high chemical oxygen demand (COD) of 45,000 to 75,000 mg/l and low pH values of 4.3 to 5.3. The results of this study highlighted the selection, physical properties and performance of carrier materials on biomass retention. This study has also clearly indicated that perlite proves to be a suitable carrier material for high biomass retention and improvement of the reactor performances in a short time of operation.

Hydrogen and ethanol production in anaerobic fluidized bed reactors: Performance evaluation for three support materials under different operating conditions

The objective of this study was to evaluate the influence of different support materials (polystyrene – R1, grounded tire – R2 and polyethylene terephthalate (PET) – R3) on producing hydrogen and ethanol using three anaerobic fluidized bed reactors. Each reactor had a total volume of 4192cm3 and was fed with media containing glucose as the carbon source (4000mgL−1) with an influent pH around 5.0 and an effluent pH of about 3.5, a hydraulic retention time (HRT) of 8–1h at a temperature of 23±2°C, with thermal treatment of the inoculum. For hydrogen production, the best performance was achieved with R2 (2.11molH2mol−1 glucose), providing the highest H2 content in biogas (60%). In all reactors, the predominant soluble metabolites were acetic acid, butyric acid, lactic acid and ethanol, with small amounts of propionic acid. The reactor R2 produced more acetic and butyric acid (434.74 and 1013.61mgL−1, respectively). However, reactor R3 showed a better performance for ethanol concentration (1941.78mgL−1).

Study on the Treatment of Cold Rolling Wastewater by Using Bio-Fluidized Bed

Cold rolling wastewater is very difficult for treatment with high oil content, complex composition, toxicity and other characteristics. In the conventional treatment process, the most widely used methods are ultrafiltration(UF), gas-energy-management(GEM) and membrane bioreactor(MBR). In this study, we used the biological fluidized bed to treat the cold rolling wastewater, which made the bioaugmentation apply to anaerobic biofilter and biological fluidized bed (BF-BFB) combined process, and the optimal process parameters were determined. The contents of COD and NH4+-N were 3276.8mg/L and 67.65mg/L in inflow water, and after treatment, they were reduced to 108.8mg/L and 6.36mg/L, respectively. The removal rates of COD and NH4+-N were 96.68% and 91.01%.

Electricity Generation from Wastewater Using an Anaerobic Fluidized Bed Microbial Fuel Cell

The anaerobic fluidized bed microbial fuel cell (AFBMFC) was developed to generate electricity while simultaneously treating wastewater. During a complete cycle, the AFBMFC continuously generated electricity with a maximum power density of 1100 mW/m2 and removal of total chemical oxygen demand (COD) of 89%. To achieve this power density, the artificial electron-mediator neutral red (NR) was employed in the anode chamber. Granular biological electrodes, fluidization behavior, electron mediators, and temperature were evaluated to improve power production and wastewater treatment efficiency. The results showed that the maximum power density production of granule-graphite AFBMFC was 530 mW/m2, much higher than 410 mW/m2 using a granular activated carbon AFBMFC in the same reactor. Fluidization behaviors enhance the mass transfer and momentum transfer between activated carbon and wastewater. The power density increased with increasing methylene blue (MB) and NR concentration. Furthermore, power density reveals a slight increase as MB and NR concentrations exceed 0.5 and 1.7 mmol/L. The optimum temperature ranges from 23 to 40 °C. The Coulombic efficiency was 9.3% under the best operating conditions.

Molecular analysis of the biomass of a fluidized bed reactor treating synthetic vinasse at anaerobic and micro-aerobic conditions

The microbial communities (Bacteria and Archaea) established in an anaerobic fluidized bed reactor used to treat synthetic vinasse (betaine, glucose, acetate, propionate, and butyrate) were characterized by denaturing gradient gel electrophoresis (DGGE) and phylogenetic analysis. This study was focused on the competitive and syntrophic interactions between the different microbial groups at varying influent substrate to sulfate ratios of 8, 4, and 2 and anaerobic or micro-aerobic conditions. Acetogens detected along the anaerobic phases at substrate to sulfate ratios of 8 and 4 seemed to be mainly involved in the fermentation of glucose and betaine, but they were substituted by other sugar or betaine degraders after oxygen application. Typical fatty acid degraders that grow in syntrophy with methanogens were not detected during the entire reactor run. Likely, sugar and betaine degraders outnumbered them in the DGGE analysis. The detected sulfate-reducing bacteria (SRB) belonged to the hydrogen-utilizing Desulfovibrio. The introduction of oxygen led to the formation of elemental sulfur (S(0)) and probably other sulfur compounds by sulfide-oxidizing bacteria (γ-Proteobacteria). It is likely that the sulfur intermediates produced from sulfide oxidation were used by SRB and other microorganisms as electron acceptors, as was supported by the detection of the sulfur respiring Wolinella succinogenes. Within the Archaea population, members of Methanomethylovorans and Methanosaeta were detected throughout the entire reactor operation. Hydrogenotrophic methanogens mainly belonging to the genus Methanobacterium were detected at the highest substrate to sulfate ratio but rapidly disappeared by increasing the sulfate concentration.

Effects of influent DO/COD ratio on the performance of an anaerobic fluidized bed reactor fed low-strength synthetic wastewater

The effect of influent DO/COD (dissolved oxygen/chemical oxygen demand) ratio on the performance of an anaerobic fluidized bed reactor (AFBR) containing GAC was studied. A high influent DO concentration was found to have adverse impacts on organic removal efficiency, methane production, and effluent suspended solids (SS) concentration. These problems resulted with a DO/COD ratio of 0.12, but not at a lower ratio of 0.05. At first organic removal appeared satisfactory at the higher DO/COD ratio at a hydraulic retention time of 0.30h, but soon a rapid growth of oxygen-consuming zoogloeal-like organisms resulted, eventually causing high effluent SS concentrations. The influent DO also had an inhibitory effect, resulting in a long recovery time for adequate methanogenic activity to return after influent DO removal began. With the growing interest in anaerobic treatment of low COD wastewaters, the increased possibility of similar adverse DO effects occurring needs consideration.

The effect of temperature and effluent recycle rate on hydrogen production by undefined bacterial granules

Biohydrogen production in an anaerobic fluidized granular bed bioreactor was strongly dependent on temperature and effluent recycle rates. At 45°C as the effluent recycle rate was increased from 1.3 to 3.5L/min, the total H2 output for the bioreactor increased from 10.6 to 43.2L/h. Volumetric H2 productivity also increased from 2.1 to 8.7L H2/L/h. At 70°C as the effluent recycle was increased from 1.3 to 3.5L/min, the total H2 output for the bioreactor increased from 13.8 to 73.8L/h. At 70°C volumetric H2 productivities increased from 2.8 to 14.8L H2/L/h as the effluent recycle rate was increased from 1.3 to 3.5L/min. At 45°C % H2 was 45% and reached 67% at 70°C. Maximum hydrogen yields at 45°C were 1.24 and 2.2mol H2/mol glucose at 70°C.

Electricity generation during wastewater treatment: An approach using an AFB-MFC for alcohol distillery wastewater

Wastewater is not just waste but could also be sources of energy. Along with many biological approaches, the microbial fuel cell (MFC) has been demonstrated its capability for wastewater treatment and electricity generation. However, the factors, wastewater treatment efficiency, capability of electricity generation and the scaled-up capability, have been limited its application at a large scale. In order to improve the application capacity of the MFC, a system combining an anaerobic fluidized bed (AFB) and a MFC was designed in this study. It was used to treat alcohol distillery wastewater and generate electricity simultaneously. In this study, the COD removal efficiency is from 80–90% in stabilization period. A maximum power density of 124.03mW/m2 was achieved under an external resistance of 120Ω and a variety of system operational settings. Furthermore, a longer hydraulic retention time (HRT) leads to a higher COD removal efficiency. Key factors influencing the electricity generation capacity of the AFB-MFC include the external resistance, the conductivity of the influent, anolyte, and catholyte. These results indicate that the AFB-MFC can be used for electricity generation at a large scale while alcohol distillery wastewater can be efficiently treated under appropriate system operational settings.

ผลของอัตราภาระสารอินทรีย์ต่อสมรรถนะของระบบแอนแอโรบิกฟลูอิดไดซ์เบดที่ใช้เม็ดยางเป็นวัสดุตัวกลาง (Effect of Organic Loading Rate on Performance of Anaerobic Fluidized Bed Using Rubber Granule as a Media)

Normal 0 false false false EN-US X-NONE TH MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:ตารางปกติ; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; mso-bidi-font-size:14.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Cordia New"; mso-bidi-theme-font:minor-bidi;} งานวิจัยนี้เป็นการศึกษาการใช้เม็ดยางที่ผลิตจากเศษยางรถยนต์ที่ใช้แล้ว เพื่อนำมาใช้เป็นวัสดุตัวกลางในระบบบำบัดน้ำเสียแบบแอนแอโรบิกฟลูอิดไดซ์เบด โดยบำบัดน้ำเสียสังเคราะห์ที่มีค่าซีโอดีประมาณ 2,500  5,000 7,500 และ 10,000  มก./ล. (เทียบเท่ากับอัตราภาระสารอินทรีย์ 5 10 15 และ 20  กก.ซีโอดี/ลบ.ม.-วัน) และควบคุมระยะเวลากักน้ำคงที่ที่ 12 ชม. เพื่อหาประสิทธิภาพในการกำจัดซีโอดีและการเกิดก๊าซชีวภาพ จากการทดลองพบว่า ระบบมีสมรรถนะที่ดีในการบำบัดน้ำเสียสังเคราะห์ทั้งในแง่ของประสิทธิภาพการกำจัดซีโอดีและ  มีอัตราการเกิดก๊าซชีวภาพสูง โดยที่อัตราภาระสารอินทรีย์ 5 10 15 และ 20 กก.ซีโอดี/ลบ.ม.-วัน ระบบมีประสิทธิภาพในการกำจัดซีโอดีประมาณร้อยละ 78.38  94.80  97.70  และ 94.60 และมีอัตราการเกิดก๊าซชีวภาพ  0.60  0.61  0.62 และ 0.60 ล./ก.ซีโอดีที่ถูกกำจัด ตามลำดับ นั่นคือที่อัตราภาระสารอินทรีย์ 15 กก.     ซีโอดี/ลบ.ม.-วัน ระบบมีประสิทธิภาพกำจัดซีโอดีและการเกิดก๊าซชีวภาพสูงสุด โดยมีร้อยละของมีเทนในก๊าซชีวภาพเท่ากับ 55.30 สอดคล้องกับผลการศึกษาชนิดของจุลินทรีย์บนเม็ดตัวกลางด้วยเทคนิค Fluorescent In Situ Hybridization (FISH) ที่พบปริมาณอาร์เคียมากกว่าแบคทีเรียอย่างชัดเจน   ABSTRACT   This research investigated the use of crumb rubber as a media in the Anaerobic Fluidized Bed (AFB) process for treating synthetic wastewater. The synthetic wastewater was prepared from tap water using sucrose as carbon source with sufficient nutrients. High COD concentration about 2,500, 5,000, 7,500, and 10,000 mg/l, which equal to 5, 10, 15, and 20 kg.COD/m 3 -d organic loading rate (OLR) respectively, were fed into a 12 hr detention time anaerobic fluidized bed reactor. The efficiencies of COD removal and biogas production were investigated. For the OLR 5, 10, 15 and 20 kg.COD/m 3 -d, the average COD removal were 78.38, 94.80, 97.70, and 94.60%, respectively ; whereas the biogas production was about 0.60, 0.61, 0.62, and 0.60 l/g.COD removed, respectively. For the organic loading rate of 15 kg.COD/m 3 -day, the result indicated the highest COD removal and biogas production, which percentage of methane in the biogas was 55.30 %. Moreover, Fluorescent in situ hybridization (FISH) results showed that the quantity of archaea adhered throughout the whole support materials was significantly greater than bacteria. These outcomes are consistent with the result of COD removal efficiencies and biogas production. &nbsp

Bio-hydrogen behavior of suspended and attached microorganisms in anaerobic fluidized bed

An anaerobic fluidized bed reactor (110 L AnFBR) which kitchen waste (KW) was fed as the major substrate and different weight fractions of napiergrass dregs as the supplemental ones for bio-hydrogenation at long hydraulic retention time of 7.3 days was established. Two types of microorganisms could be distinguished by their life surroundings in the microbial community of the AnFBR: one is suspended growth, the other is attached growth. In order to evaluate the biohydrogen potential and kinetic characteristics of the two microbial growths in the AnFBR, a series of biodegradation batch experiments were conducted as the biochemical hydrogen potential test. The suspended microbe had obvious bio-hydrogen production after 3.6 h of lag phase, and the maximum specific hydrogen production rate achieved at 2.65 mmol/g-VSS-hr; the attached microbe stayed longer lag phase about 20 h and the maximum specific hydrogen production rate reached up to 1.06 mmol/g-VSS-hr. The metabolism study was investigated with volatile fatty acids conversion with initial, middle and final constitutes. The huge amount of lactic acid degradation of suspended growth (about 6000 mg/L degradation) displayed a special phenomenon in fermentative hydrogen production. Scanning electron microscope (SEM) was used to observe the morphology of two cultures. We also performed a terminal restriction fragment length polymorphism (T-RFLP) analysis for the diverse microbial identification.