• Title/Summary/Keyword: anaerobic

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Performance and Spatial Succession of a Full-Scale Anaerobic Plant Treating High-Concentration Cassava Bioethanol Wastewater

  • Gao, Ruifang;Yuan, Xufeng;Li, Jiajia;Wang, Xiaofen;Cheng, Xu;Zhu, Wanbin;Cui, Zongjun
    • Journal of Microbiology and Biotechnology
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    • v.22 no.8
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    • pp.1148-1154
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    • 2012
  • A novel two-phase anaerobic treatment technology was developed to treat high-concentration organic cassava bioethanol wastewater. The start-up process and contribution of organics (COD, total nitrogen, and $NH_4^+$-N) removal in spatial succession of the whole process and spatial microbial diversity changing when sampling were analyzed. The results of the start-up phase showed that the organic loading rate could reach up to $10kg\;COD/m^3d$, with the COD removal rate remaining over 90% after 25 days. The sample results indicated that the contribution of COD removal in the pre-anaerobic and anaerobic phases was 40% and 60%, respectively, with the highest efficiency of 98.5%; TN and $NH_4^+$-N had decreased to 0.05 g/l and 0.90 g/l, respectively, and the mineralization rate of total nitrogen was 94.8%, 76.56% of which was attributed to the anaerobic part. The microbial diversity changed remarkably among different sample points depending on the physiological characteristics of identified strains. Moraxellaceae, Planococcaceae, and Prevotellaceae were dominant in the pre-anaerobic phase and Bacteroidetes, Campylobacterales, Acinetobacter, Lactobacillus, Clostridium, and Bacillus for the anaerobic phase. Methanosarcinaceae and Methanosaeta were the two main phylotypes in the anaerobic reactor.

Effects of Pinitol Supplementation and Strength Training on Anaerobic Performance and Status of Energy Substrates in Healthy Young Men

  • Lee, Dae-Taek;Lee, Woon-Yong
    • Nutritional Sciences
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    • v.8 no.3
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    • pp.189-195
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    • 2005
  • To assess the effect of pinitol supplementation and strength training for two weeks on the anaerobic capacity during and after exercise, and improvement of glucose metabolism during the recovery period of muscular fatigue with repeated acute bouts of cycling exercise, a total of 24 healthy young men were recruited and randomly and equally divided into three groups; pinitol supplementation group (PSG), placebo group (PLG), and control group (CON). Using a randomized double-blinded design, subjects in PSG were provided pinitol supplement, consumed orally 1.2 g/day, and participated in the resistance exercise program and cycling exercise for two weeks. Subjects in PLG underwent the same protocol as those in PSG but consumed the same amount of placebo. No supplementation and exercise program was given to CON. Before and after the intervention, all subjects were tested for their anaerobic capacities evaluated by Wingate test twice separated by 30 min. During the test, peak anaerobic power (PP), mean anaerobic power, total work, and fatigue index were evaluated During resting and recovery, blood samples were drawn and plasma pinitol, myo-inositol, chiro-inositol, insulin, free fatty acid, glucose, and lactate levels were analyzed After two weeks, PP and relative PP of the second biking were improved from the first biking in PSG only (p<0.05). No changes were found in all other variables of Wingate test in all groups. No statistical differences between groups and pre- and post-intervention were observed in concentrations of pinitol, myo-inositol, and chiro-inositol, but pinitol concentration was higher during recovery compared to the baseline in all groups and testings (p<0.05). Lactate level during recovery was higher than the resting level, but no other blood parameters were significantly changed. In conclusion, two weeks of pinitol supplementation in conjunction with short duration of anaerobic training in healthy young men did not induce any obvious benefits in terms of anaerobic capacity and energy metabolism Individual and/or population susceptibility may be one factor responsible for adopting pinitol supplementation.

Performance Evaluation of Anaerobic Bioreactors and Effects of Ammonia on Anaerobic Digestion in Treating Swine Wastewaters

  • Lee, Gook-Hee;Seo, Jun-Won;Kim, Jong-Soo
    • Korean Journal of Environmental Agriculture
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    • v.25 no.3
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    • pp.195-201
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    • 2006
  • The operational characteristics of anaerobic bioreactors in treating swine wastewater were evaluated upto hydraulic retention time (HRT) of 1 day and organic loading rate (OLR) of $5.1kg-COD/m^3{\cdot}d$ for 200 days. The bioreactors were effective in treating swine wastewaters with COD removal efficiency of $78.9{\sim}81.5%$ and biogas generation of $0.39{\sim}0.59m^3/kg-COD_r$ at OLR of $1.1{\sim}2.2kg-COD/m^3{\cdot}d$. The two-stage ASBF anaerobic bioreactors was effective in treating different characteristics of swine wastewaters since they showed high and stable COD removal efficiency at high OLR due to effective retention of biomass by media and staging. The effects of ammonia on anaerobic digestion were investigated by operating two-stage ASBF reactors using swine wastewaters as influent without and with ammonia removal at HRT of $1{\sim}2$ days and OLR of $2.2{\sim}9.6kg-COD/m^3{\cdot}d$ for 250 days. The COD removal efficiency and biogas generation of two-stage ASBF reactors was decreased by increasing influent ammonia concentrations to 1,580 mg (T-N)/L with increasing OLR to $6.3kg-COD/m^3{\cdot}d$, while those were increased by maintaining influent ammonia concentrations below 340 mg (T-N)/L by MAP precipitation with increasing OLR to $9.6kg-COD/m^3{\cdot}d$. Initial inhibition of ammonia on anaerobic processes was observed at a concentration of 760 mg (T-N)/L and the COD removal efficiency and biogas generation dropped to 1/2 at ammonia concentration ranges of $1,540{\sim}1,870mg$ (T-N)/L. It is essential to remove ammonia in swine wastewaters to an initial inhibition level before anaerobic processes for the effective removal of COD.

항생물질을 생산하는 혐기성 세균의 탐색

  • 정은영;김병홍
    • Microbiology and Biotechnology Letters
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    • v.24 no.5
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    • pp.636-639
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    • 1996
  • To develop new biologically active compounds produced by anaerobes, 677 soil samples were collected and used to isolate 1, 889 anaerobic bacteria. Among the isolates 427 strains were strict anaerobes and the remaining 1, 462 strains were facultative anaerobes. From 427 strictly anaerobic isolates, 88 strains showed antibacterial activities, and 21 strains were selected for the further studies.

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Anaerobic Treatment of Piggery Slurry - Review -

  • Chynoweth, D.P.;Wilkie, A.C.;Owens, J.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.4
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    • pp.607-628
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    • 1999
  • The swine waste industry is growing rapidly along with the world human population. The trend is toward more concentrated piggeries with numbers of herds in the thousands. Associated with these increased herds are large quantities of wastes, including organic matter, inorganic nutrients, and gaseous emissions. The trend in swine waste management is toward treatment of these wastes to minimize negative impact on the health and comfort of workers and animals and the atmosphere, water, and soil environments. Treatment of these wastes has traditionally involved land application, lagoons, oxidation ditches, and conventional batch and continuously stirred reactor designs. More sophisticated treatment systems are being implemented, involving advanced anaerobic digester designs, integrated with solids separation, aerobic polishing of digester effluents, and biological nutrient removal. This review discusses the present and future role of anaerobic processes in piggery waste treatment with emphasis on reactor design, operating and performance parameters, and effluent processing.

Inhibition of methane formation and improvement of $H_2$ production by adding nitrate to anaerobic reactor

  • Kim, Jeong-Ok;Kim, Yong-Hwan;Ryu, Jeong-Yong;Song, Bong-Keun;Kim, In-Ho
    • 한국생물공학회:학술대회논문집
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    • 2003.10a
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    • pp.129-134
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    • 2003
  • Anaerobic hydrogen production was executed using mixed anaerobic sludge. pH control (pH $5.5^{\sim}6.2)$ and heat treatment of anaerobic sluge at $92^{\circ}C$ was not effective for repressing the methane formation. The addition of $nitrate(500^{\sim}2,000\;mg/L\;KNO_3)$ made it possible to repress the methane formation, which resulted in the improvement of hydrogen production. By using SEM(Scanning Electron Microscope), less methane forming microbial with spagetti shape was observed when nitrate was supplied to anaerobic reactor.

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Microscope Examination of Attached Biofilm under Anaerobic Conditions (혐기성 조건에서 담체에 부착된 미생물의 관찰)

  • 박성열;김도한;나영수;박영식;송승구
    • Journal of Environmental Health Sciences
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    • v.27 no.1
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    • pp.100-105
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    • 2001
  • Microstructural examinations were performed on the anaerobic biofilm from reactor filled with PE support media. Optical microscope, SEM and fluorescent microscope were used for qualitative and morphological studies on the attached microorganism under anaerobic condition. Microorganisms were attached in crevices where protection from shear forces of surfaces where easy to contact with support media surface. A hypothesis for biofilm accumulation occurs on a surface such as polymer support media is presented schematically : 1st step ; cell-support media attachment, 2nd step ; cell-support media attachment and cell-cell attachment, 3rd step ; attached biofilm from neighboring crevices joins together and growing, 4th step ; mature and irregualar biofilm was formed. In SEM photographs, shape and structures of biofilm were observed, but microorganism species and methanogens were not identified. A large number of methanogenic bacteria were identified on the surface of PE substratum by fluorescence under 480nm of radiation and it was estimated that methanogenic bacteria was related to initial attachment of bacteria under anaerobic condition.

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Mixing effect on organic removal efficiency in treating low-strength wastewater using a modified anaerobic filter reactor (변형 혐기성 여상 반응조에서 교반강도가 유기물 제거효율에 미치는 영향)

  • 정병곤;이헌모
    • Journal of Environmental Science International
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    • v.5 no.4
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    • pp.513-524
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    • 1996
  • Laboratory investigation was conducted to evaluat the mixing effects on organic removal efficiency to treat low-strength synthetic wastewater using modified anaerobic - filter reactor combining anaerobic filter and upflow anaerobic sludge blanket. Using the modified process the low-strength wastewater like municipal sewage could be treated with 85% T-COD removal efficiency at hydraulic retention time of 6 hours. At the constant organic loading of 0.5 kg COD/m 3-day, the organic removal efficiency and effluent COD concentration are increased as influent COD concentration increased from 125 mg/l to 500 mg/l. Mixing effects on organic removal efficiency are evident and optimum mixing speed is found as 50RPM. Placing the granular sludge and media on which slime layer was pre-formed into the reactor seemed to be very effective In achieving short start-up period. Therefore, the steady state was achived after 4 weeks and 1 week based on T-COD and S-COD, respectively.

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Anaerobic digestate as a nutrient medium for the growth of the green microalga Neochloris oleoabundans

  • Abu Hajar, Husam A.;Guy Riefler, R.;Stuart, Ben J.
    • Environmental Engineering Research
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    • v.21 no.3
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    • pp.265-275
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    • 2016
  • In this study, the microalga Neochloris oleoabundans was cultivated in a sustainable manner using diluted anaerobic digestate to produce biomass as a potential biofuel feedstock. Prior to microalgae cultivation, the anaerobic digestate was characterized and several pretreatment methods including hydrogen peroxide treatment, filtration, and supernatant extraction were investigated and their impact on the removal of suspended solids as well as other organic and inorganic matter was evaluated. It was found that the supernatant extraction was the most convenient pretreatment method and was used afterwards to prepare the nutrient media for microalgae cultivation. A bench-scale experiment was conducted using multiple dilutions of the supernatant and filtered anaerobic digestate in 16 mm round glass vials. The results indicated that the highest growth of the microalga N. oleoabundans was achieved with a total nitrogen concentration of 100 mg N/L in the 2.29% diluted supernatant in comparison to the filtered digestate and other dilutions.