• Title/Summary/Keyword: Anaerobic and aerobic

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Disposal of Animal Waste-The Magnitude of the Problem in Asia and Australasia - Review -

  • Sheen, S.Y.;Hong, C.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.4
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    • pp.597-603
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    • 1999
  • Even though the development of livestock industry in Asia and Australasia has brought the economic growth and thus elevated the living standard in these areas, it has also brought the pollution caused by the increasing amount of animal wastes. Among them, Japan probably is the first country that suffered from the animal waste pollution as early as in 1970s. Nowadays, the animal waste pollution has been a common problem for almost every countries in this region. To solve it, different measures and regulations have been implemented in many countries. In this paper, different methods for animal waste disposal are discussed, including: manure-bed animal housing, composting, anaerobic treatment, odor control, utilization of biogas, aerobic treatment, three-step process, N and P removal, land application, cultivation of algae, anaerobic treatment of dead animals. It is hoped that an animal industry without pollution can be achieved in the future.

Biodegradation of Polynuclear Aromatic Hydrocarbons in soil using microorganisms under anaerobic conditions (혐기성 미생물에 의한 토양내 다핵성방향족화합물의 생물학적 분해)

  • An, Ik-Seong
    • 한국생물공학회:학술대회논문집
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    • 2000.04a
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    • pp.89-91
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    • 2000
  • Polynuclear aromatic hydrocarbon (PAH) compounds are highly carcinogenic chemicals and common groundwater contaminants that are observed to persist in soils. The adherence and slow release of PAHs in soil is an obstacle to remediation and complicates the assessment of cleanup standards and risks. Biological degradation of PAHs in soil has been an area of active research because biological treatment may be less costly than conventional pumping technologies or excavation and thermal treatment. Biological degradation also offers the advantage to transform PAHs into non-toxic products such as biomass and carbon dioxide. Ample evidence exists for aerobic biodegradation of PAHs and many bacteria capable of degrading PAHs have been isolated and characterized. However, the microbial degradation of PAHs in sediments is impaired due to the anaerobic conditions that result from the typically high oxygen demand of the organic material present in the soil, the low solubility of oxygen in water, and the slow mass transfer of oxygen from overlying water to the soil environment. For these reasons, anaerobic microbial degradation technologies could help alleviate sediment PAH contamination and offer significant advantages for cost-efficient in-situ treatment. But very little is known about the potential for anaerobic degradation of PAHs in field soils. The objectives of this research were to assess: (1) the potential for biodegradation of PAH in field aged soils under denitrification conditions, (2) to assess the potential for biodegradation of naphthalene in soil microcosms under denitrifying conditions, and (3) to assess for the existence of microorganisms in field sediments capable of degrading naphthalene via denitrification. Two kinds of soils were used in this research: Harbor Point sediment (HPS-2) and Milwaukee Harbor sediment (MHS). Results presented in this seminar indicate possible degradation of PAHs in soil under denitrifying conditions. During the two months of anaerobic degradation, total PAH removal was modest probably due to both the low availability of the PAHs and competition with other more easily degradable sources of carbon in the sediments. For both Harbor Point sediment (HPS-2) and Milwaukee Harbor sediment (MHS), PAH reduction was confined to 3- and 4-ring PAHs. Comparing PAH reductions during two months of aerobic and anaerobic biotreatment of MHS, it was found that extent of PAHreduction for anaerobic treatment was compatible with that for aerobic treatment. Interestingly, removal of PAHs from sediment particle classes (by size and density) followed similar trends for aerobic and anaerobic treatment of MHS. The majority of the PAHs removed during biotreatment came from the clay/silt fraction. In an earlier study it was shown that PAHs associated with the clay/silt fraction in MHS were more available than PAHs associated with coal-derived fraction. Therefore, although total PAH reductions were small, the removal of PAHs from the more easily available sediment fraction (clay/silt) may result in a significant environmental benefit owing to a reduction in total PAH bioavailability. By using naphthalene as a model PAH compound, biodegradation of naphthalene under denitrifying condition was assessed in microcosms containing MHS. Naphthalene spiked into MHS was degraded below detection limit within 20 days with the accompanying reduction of nitrate. With repeated addition of naphthalene and nitrate, naphthalene degradation under nitrate reducing conditions was stable over one month. Nitrite, one of the intermediates of denitrification was detected during the incubation. Also the denitrification activity of the enrichment culture from MHS slurries was verified by monitoring the production of nitrogen gas in solid fluorescence denitrification medium. Microorganisms capable of degrading naphthalene via denitrification were isolated from this enrichment culture.

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Effect of Oxygen on the Browning of Soy Sauce During Storage (간장의 저장 중 갈색화반응에 대한 산소의 영향)

  • Park, Seung-Kyu;Han, Chang-Geun;Kyung, Kyu-Hang;Yoo, Yang-Ja
    • Korean Journal of Food Science and Technology
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    • v.22 no.3
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    • pp.307-311
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    • 1990
  • Raw soy sauce and raw soy sauce added with several Maillard reactants (glucose, xylose, glycine), preheated or unheated, were stored under aerobic or anaerobic conditions to investigate the effect of oxygen on the browning of soy sauce. All experimental groups, except xylose-added groups, stored under aerobic condition browned about 2.5 times as much as those stored under anaerobic condition. Soy sauce added with xylose stored under aerobic condition browned about 1.5 times as much as that stored under anaerobic condition. Contrarily, there have been no consistent differences in the browning except the initial 10% difference between preheated and unheated samples, implying that biological (microbiological and enzymatic) browning was not important in the browning of commercially brewed soy sauce.

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Effects of organic/inorganic carbon source on the biological luxury-uptake of phosphorus by cyanobacteria Synechococcus sp. (남조류 Synechococcus sp.의 혐기-호기법에 의한 인 과잉섭취 효율에 미치는 유기/무기 탄소원의 영향)

  • Yu, Mi-Yeong;Kim, Yun-Ji;Choi, Yun-Jeong;Hwang, Sun-Jin
    • Journal of Korean Society of Water and Wastewater
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    • v.34 no.6
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    • pp.437-443
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    • 2020
  • Biological phosphorus removal is accomplished by exposing PAO(phosphorus accumulating organisms) to anaerobic-aerobic conversion conditions. In the anaerobic condition, PAO synthesize PHB(polyhydroxybutyrate) and simultaneously hydrolysis of poly-p resulting phosphorus(Pi) release. In aerobic condition, PAO uptake phosphorus(Pi) more than they have released. In this study, cyanobacteria Synechococcus sp., which is known to be able to synthesize PHB like PAO, was exposed to anaerobic-aerobic conversion. If Synechococcus sp. can remove excess phosphorus by the same mechanism as PAO, synergistic effects can occur through photosynthesis. Moreover, Synechococcus sp. is known to be capable of synthesizing PHB using inorganic carbon as well as organic carbon, so even if the available capacity of organic carbon decreases, it was expected to show stable phosphorus removal efficiency. In 6 hours of anaerobic condition, phosphorus release occurred in both inorganic and organic carbon conditions but SPRR(specific phosphorus release rate) of both conditions was 10 mg-P/g-MLSS/day, which was significantly lower than that of PAO. When converting to aerobic conditions, SPUR(specific phosphorus uptake rate) was about 9 mg-P/g-MLSS/day in both conditions, showing a higher uptake rate than the control condition showing SPUR of 6.4 mg-P/g-MLSS/day. But there was no difference in terms of the total amount of removal. According to this study, at least, it seems to be inappropriate to apply Synechococcus sp. to luxury uptake process for phosphorus removal.

Anaerobic Microbial Degradation of Lignocellulose and Lignolic Compounds (미생물에 의한 섬유질과 리그닌 유도체의 혐기적 분해)

  • 김소자;김욱한
    • The Korean Journal of Food And Nutrition
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    • v.4 no.1
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    • pp.99-107
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    • 1991
  • Lignocellulose and lignolic compounds were absolutely given much weight In the biosphere, and their degradation was essential for continuous biological carbon circulation. Whereas aerobic cellulolytic microorganism dissolved the cellulose into their elements in the first stage, strict anaerobic cellulolytic microorganism's role was taken I increasing interest through the recent research. It was reviewed that anaerobic microbial degradation process of lignocellulose and its derivatives (cellulose, lignin, oligolignol and monoaromatic compound), and function of anaerobic microorganism on the. environmental ecology.

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Culture-Based and Denaturing Gradient Gel Electrophoresis Analysis of the Bacterial Community Structure from the Intestinal Tracts of Earthworms (Eisenia fetida)

  • Hong, Sung-Wook;Kim, In-Su;Lee, Ju-Sam;Chung, Kun-Sub
    • Journal of Microbiology and Biotechnology
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    • v.21 no.9
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    • pp.885-892
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    • 2011
  • The bacterial communities in the intestinal tracts of earthworm were investigated by culture-dependent and -independent approaches. In total, 72 and 55 pure cultures were isolated from the intestinal tracts of earthworms under aerobic and anaerobic conditions, respectively. Aerobic bacteria were classified as Aeromonas (40%), Bacillus (37%), Photobacterium (10%), Pseudomonas (7%), and Shewanella (6%). Anaerobic bacteria were classified as Aeromonas (52%), Bacillus (27%), Shewanella (12%), Paenibacillus (5%), Clostridium (2%), and Cellulosimicrobium (2%). The dominant microorganisms were Aeromonas and Bacillus species under both aerobic and anaerobic conditions. In all, 39 DNA fragments were identified by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis. Aeromonas sp. was the dominant microorganism in feeds, intestinal tracts, and casts of earthworms. The DGGE band intensity of Aeromonas from feeds, intestinal tracts, and casts of earthworms was 12.8%, 14.7%, and 15.1%, respectively. The other strains identified were Bacillus, Clostridium, Enterobacter, Photobacterium, Pseudomonas, Shewanella, Streptomyces, uncultured Chloroflexi bacterium, and uncultured bacterium. These results suggest that PCR-DGGE analysis was more efficient than the culturedependent approach for the investigation of bacterial diversity and the identification of unculturable microorganisms.

Removal of Simultaneously Biological Organic, Nitrogen, and Phosphorus Removal in Sequencing Batch Reactors using Night-soil (연속회분식 반응기(Sequencing Batch Reactor)를 이용한 분뇨중 유기물과 질소 및 인의 동시제거)

  • 한기백;박동근
    • Journal of Environmental Science International
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    • v.6 no.6
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    • pp.697-709
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    • 1997
  • Sequencing Batch Reactor(SBR) experiments for organics and nutrients removal have been conducted to find an optimum anaerobic/anoxic/aerobic cycling time and evaluate the applicability of oxidation-reduction potential(ORP) as a process control parameter. In this study, a 61 bench-scale plant was used and fed with night-soil wastewater in K city which contained TCODcr : 10, 680 mg/l, TBm : 6, 893 mg/l, $NH_4^+-N$ : 1, 609 mg/l, $PO_4^{3-}-P$ : 602 mg/l on average. The cycling time In SBRs was adjusted at 12 hours and 24 hours, and then certainly included anaerobic, aerobic and inoxic conditions. Also, for each cycling time, we performed 3 series of experiment simultaneously which was set up 10 days, 20 days and 30 days as SRT From the experimental results, the optimum cycling time for biological nutrient removal with nlght-soil wastewater was respctively 3hrs, 5hrs, 3hrs(anaerobic-aerobic-anoxic), Nitrogen removal efficiency was 77.9%, 77.9%, 81.7% for each SRT, respectively. When external carbon source was fed in the anoxic phase, ORP-bending point indicating nitrate break point appeared clearly and nitrogen removal efficiency increased as 96.5%, 97.1%, 98.9%. Phosphate removal efficiency was 59.8%, 64.571, 68.6% for each SRT. Also, we finded the applicability of ORP as a process control parameter in SBRs.

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Effects of Exercise Intensity on Hand Steadiness (운동 강도가 손 안정성에 미치는 영향)

  • Han, Seung Jo;Kim, Sun-Uk;Koo, Kyo Chan
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.36 no.1
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    • pp.1-7
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    • 2013
  • This study is aimed to investigate the association between anaerobic-aerobic exercise intensity and hand steadiness. Hand steadiness is the decisive contributor to affecting the job performance just as in the rifle shooting and archery in sports and the microscope-related jobs requiring hand steadiness in industries. In anaerobic exercise condition hand steadiness is measured through hand steadiness tester having 9 different diameter holes after each subject exerts 25%, 50%, 75%, and 100% of maximum back strength. In aerobic exercise occasion it is evaluated at each time heart rate reaches 115%, 130%, and 145% of reference heart rate measured in no task condition after they do jumping jack. The results indicate that an increased intensity in both types of exercise reduces hand steadiness, but hand steadiness at 25% of maximum back strength and 115% of reference heart rate is rather greater than at no exercise. Just as the relation between cognitive stress and job performance has upside-down U form, so does the association of physical loading to hand steadiness, which means that a little exercise tends to improve hand steadiness in comparison with no exercise.

Comparison of Liquid Composting Efficiency using Liquid Pig Manure in Different Condition (가축분뇨 슬러리 액비 부숙 조건별 특성비교)

  • Jung, Kwang-Yong;Cho, Nam-Jun;Jeong, Yee-Geun
    • Korean Journal of Environmental Agriculture
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    • v.17 no.4
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    • pp.301-305
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    • 1998
  • This study was conducted to evaluate the liquid composting efficiency using pig manure in different condition such as simple storage type reactor, continuous aeration reactor, anaerobic reactor and anaerobic agitation reactor. Continuous aeration reactor was the most efficiency method to BOD and malodors removal than other methods. While nitrogen loss in continuous aeration reactor was 47% of initial concentration, which was the higher amount than any other digestion methods. The digestion efficiency between anaerobic reactor and anaerobic agitation reactor were similar, but E. coli and malodor removal efficiency were a little higher in the anaerobic agitation reactor. Simple storage type reactor which was conventional digestion method in rural area gave lower efficiency than aerobic and anaerobic digestion methods in view of BOD, E. coli and malodor removal. The liquid composting efficiency which were evaluated by various indicators like pH, BOD, E, coli, malodor and nitrogen loss was high in the order of anaerobic agitation reactor>continuous aeration reactor>anaerobic reactor>simple storage type reactor.

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탈질조건을 이용한 유류물질 생분해 기초연구

  • 오인석;장순웅;이시진
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.04a
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    • pp.368-371
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    • 2003
  • Leaking underground storage tanks are a major source of groundwater contamination by petroleum hydrocarbons. Bioremediation of aromatic hydrocarbons in groundwater and sediments is often limited by dissolved oxygen. Aerobic bioremediation has been highly effective in the remediation of many fuel releases, but Many aromatic hydrocarbons degrade very slowly under anaerobic conditions. Nitrate is a good alternative electron acceptor to oxygen and denitrifying bacteria are commonly found in the subsurface and in association with contaminated aquifer materials. Because nitrate is less expensive and more soluble than oxygen. it may be more economical to restore fuel-contaminated aquifers using nitrate rather than oxygen. This study show that biodegradation of BTEX and MTBE is enhanced by the nitrate-amended microcosms under aerobic/anaerobic conditons. Although aromatic hydrocarbons degrade very slowly under anaerobic conditions. Biodegradaton was observed for all of the test compounds.

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