• 제목/요약/키워드: aerobic condition

검색결과 430건 처리시간 0.025초

반응성 염료의 색도제거를 위한 균주의 분리 및 성장 특성 (Isolation and Culture Characteristics of Strains for Color Removal of Reactive Dyes)

  • 김정목;한명호;임학상
    • 상하수도학회지
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    • 제12권4호
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    • pp.78-85
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    • 1998
  • Strains degrading and decolorizing reactive dyes, Procion blue HEGN and Procion red HE7B were isolated from water system, are named as RBK1 and RRK, the growth characteristics of which were investigated. Decolorization efficiencies after 42 hrs in batch culture were 95% and 77%, respectively. and the optimal culture condition of temperature and pH were $30^{\circ}C$, 7.0. Decolorization efficiencies in condition of aerobic shaking culture by strains RBK1 and RRK conspicuously increased, and culture by strain RBK1 was found as 95% after 42 hrs, while standing culture was 64%, Optimum nitrogen source was peptone, and It was found that decolorization efficiencies by strains RBK1 and RRK increased up to 4,000mg/l of peptone concentration as nitrogen source, but peptone concentration did' nt influence the decolorization efficiency in above 4,000mg/l. When the concentration of dyes were more than 800 mg/l and 400 mg/l respectively, the strains RBK1 and RRK, which degrade Procion bule HEGN and Procion red HE7B, showed a sharply decreased decolorization efficiencies; then the specific growth rate were $0.25hr^{-1}$ and $0.09hr^{-1}$.

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암모니아 센서를 이용한 간헐폭기 Membrane bioreactor공정에서의 전력비 저감과 관형막을 이용한 슬러지 농축에 관한 연구 (A study on an intermittent aeration membrane bioreactor system using ammonia sensor to decrease energy consumption and sludge concentration by tubular membrane)

  • 강희석;이의종;김형수;장암
    • 상하수도학회지
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    • 제28권2호
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    • pp.161-170
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    • 2014
  • It is essential to decrease energy consumption and excess sludge to economically operate sewage treatment plant. This becomes more important along with a ban on sea dumping and exhaustion of resource. Therefore, many researchers have been study on energy consumption reduction and strategies for minimization of excess sludge production from the activated sludge process. The aeration cost account for a high proportion of maintenance cost because sufficient air is necessary to keep nitrifying bacteria activity of which the oxygen affinity is inferior to that of heterotrophic bacteria. Also, additional costs are incurred to stabilize excess sludge and decrease the volume of sludge. There were anoxic, aerobic, membrane, deairation and concentration zone in this MBR process. Continuous aeration was provided to prevent membrane fouling in membrane zone and intermittent aeration was provided in aerobic zone through ammonia sensor. So, there was the minimum oxygen to remove $NH_4-N$ below limited quantity that could be eliminated in membrane zone. As the result of this control, energy consumption of aeration system declined by between 10.4 % and 19.1 %. Besides, we could maintain high MLSS concentration in concentration zone and this induced the microorganisms to be in starved condition. Consequentially, the amount of excess sludge decrease by about 15 %.

Influence of Electric Potential on Structure and Function of Biofilm in Wastewater Treatment Reactor : Bacterial Oxidation of Organic Carbons Coupled to Bacterial Denitrification

  • NA BYUNG KWAN;SANG BYUNG IN;PARK DAE WON;PARK DOO HYUN
    • Journal of Microbiology and Biotechnology
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    • 제15권6호
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    • pp.1221-1228
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    • 2005
  • Carbon electrode was applied to a wastewater treatment system as biofilm media. The spatial distribution of heterotrophic bacteria in aerobic wastewater biofilm grown on carbon electrode was investigated by scanning electron microscopy, atomic force microscopy, and biomass measurement. Five volts of electric oxidation and reduction potential were charged to the carbon anode and cathode of the bioelectrochemical system, respectively, but were not charged to electrodes of a conventional system. To correlate the biofilm architecture of bacterial populations with their activity, the bacterial treatment efficiency of organic carbons was measured in the bioelectrochemical system and compared with that in the conventional system. In the SEM image, the biofilm on the anodic medium of the bioelectrochemical system looked intact and active; however, that on the carbon medium of the conventional system appeared to be shrinking or damaging. In the AFM image, the thickness of biofilm formed on the carbon medium was about two times of those on the anodic medium. The bacterial treatment efficiency of organic carbons in the bioelectrochemical system was about 1.5 times higher than that in the conventional system. Some denitrifying bacteria can metabolically oxidize $H_{2}$, coupled to reduction of $NO_{3}^{-}\;to\;N_{2}$. $H_{2}$ was produced from the cathode in the bioelectrochemical system by electrolysis of water but was not so in the conventional system. The denitrification efficiency was less than $22\%$ in the conventional system and more than $77\%$ in the bioelectrochemical system. From these results, we found that the electrochemical coupling reactions between aerobic and anaerobic reactors may be a useful tool for improvement of wastewater treatment and denitrification efficiency, without special manipulations such as bacterial growth condition control, C/N ratio (the ratio of carbon to nitrogen) control, MLSS returning, or biofilm refreshing.

Measurement of Ordinary Heterotrophic Organism Active Biomass in Activated Sludge Mixed Liquor: Evaluation and Comparison of the Quantifying Techniques

  • Lee, Byung Joon;Wentzel, Mark;Ekama, George;Choi, Yun Young;Choi, Jung Woo
    • Environmental Engineering Research
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    • 제19권1호
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    • pp.91-99
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    • 2014
  • Ordinary heterotrophic organism (OHO) active biomass plays key roles in biological wastewater treatment processes. However, due to the lack of measurement techniques, the OHO active biomass exists hypothetically within the design and simulation of biological wastewater treatment processes. This research was purposed to develop a quick and easy quantifying technique for the OHO active biomass applying a modified batch aerobic growth test. Two nitrification-denitrification activated sludge systems, with 10- and 20-day sludge ages, were operated to provide well-cultured mixed liquor to the batch tests. A steady state design model was firstly applied to quantify the "theoretical" OHO active biomass concentration of the two parent systems. The mixed liquor from the parent systems was then inoculated to a batch growth test and a batch digestion test to estimate the "measured" OHO active biomass concentration in the mixed liquor. The measured OHO active biomass concentrations with the batch growth test and the batch digestion test were compared to the theoretical concentrations of the parent system. The measured concentrations with the batch growth test were generally smaller than the theoretical concentrations. However, the measured concentrations with the batch aerobic digestion tests showed a good correlation to the theoretical concentrations. Thus, a different microbial growth condition (i.e., a higher food/biomass ratio) in the batch growth test, compared to the parent system or the batch digestion test, was found to cause underestimation of the OHO active biomass concentrations.

Recombinant Production of an Inulinase in a Saccharomyces cerevisiae gal80 Strain

  • Lim, Seok-Hwan;Lee, Hong-Weon;Sok, Dai-Eun;Choi, Eui-Sung
    • Journal of Microbiology and Biotechnology
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    • 제20권11호
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    • pp.1529-1533
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    • 2010
  • The inulinase gene (INU1) from Kluyveromyces marxianus NCYC2887 was overexpressed by using the GAL10 promotor in a ${\Delta}ga180$ strain of Saccharomyces cerevisiae. The inulinase gene lacking the original signal sequence was fused in-frame to a mating factor ${\alpha}$ signal sequence for secretory expression. Use of the ${\Delta}ga180$ strain allowed for the galactose-free induction of inulinase expression using a glucose-only medium. Shake-flask cultivation in YPD medium produced 34.6 U/ml of the recombinant inulinase, which was approximately 13-fold higher than that produced by K. marxianus NCYC2887. It was found that the use of the ${\Delta}ga180$ strain improved the expression of inulinase in the recombinant S. cerevisiae in both aerobic and anaerobic conditions by about 2.9- and 1.7-fold, respectively. A 5-l fed-batch fermentation using YPD medium was performed under aerobic condition with glucose feeding, which resulted in the inulinase production of 31.7 U/ml at the $OD_{600}$ of 67. Ethanol fermentation of dried powder of Jerusalem artichoke, an inulin-rich biomass, was also performed using the recombinant S. cerevisiae expressing INU1 and K. marxianus NCYC2887. Fermentation in a 5-l scale fermentor was carried out at an aeration rate of 0.2 vvm, an agitation rate of 300 rpm, and with the pH controlled at 5.0. The temperature was maintained at $30^{\circ}C$ and $37^{\circ}C$, respectively, for the recombinant S. cerevisiae and K. marxianus. The maximum productivities of ethanol were 59.0 and 53.5 g/l, respectively.

돼지분뇨 슬러리 액비화시 폭기가 액비특성 및 슬러지 형성에 미치는 영향 (Effect of Aeration on Fertilization and Sludge Accumulation of Pig Slurry)

  • 정광화;;이명규;김중곤;한덕우;곽정훈
    • 한국축산시설환경학회지
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    • 제19권1호
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    • pp.47-54
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    • 2013
  • Two types of reactors were set to investigate the change of characteristics of pig slurry by aeration during fertilization period. One system was equipped with air diffuser to supply oxygen to pig slurry for liquid fertilization, but there was no air diffuser in the other system. Air supply to the experimental systems was regulated by air flow meter. The reactors were set up in the laboratory to protect the pig slurry from external condition such as temperature and humidity changes. Maintaining optimal pH range in the experimental reactors is an important factor for liquid fertilization of pig slurry. In this study, pH ranges of aerobic reactor and anoxic reactor was 7.04~7.19 and 7.34~7.81, respectively. The temperature of aerobic reactors was $2{\sim}3^{\circ}C$ higher then indoor temperature. The amount of sludge accumulated at the bottom layer of non-aerated reactors was 4~5 times more than that of aerated reactors.

Rhodopseudomonas sp. K-7 의 당자화성 (The Assimilability of Glucose and Xylose in Rhodopseudomonas sp. K-7.)

  • 김용효;배무
    • 한국미생물·생명공학회지
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    • 제13권2호
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    • pp.169-172
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    • 1985
  • Rhodopseudomonas K-7은 혐기 광조건과 호기암조건에서 glucose, xylose로 이용하면서 성 장할 수 있었는데, 종배양시 glucose를 첨가하는 것이 본 배양에서 glucose자화를 촉진시켰고, glucose 60mM 배지에서 배양한 것을 종균으로 했을 때, glucose이 용량이 가장 많았다. Glucose 60mM배지에서 배양한 것을 종균으로 했을 때, 배지의 glucose 농도가 높더라도 이용할 수 있는 glucose양은 제한되어 있었다. 혐기 광조건에서 보다는 호기 암조건에서 성장속도도 빨랐고, glucose, xylose자화량도 많았다.

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The Properties of Livestock Waste Composts Tea Depending on Manufacturing Method and Their Effect on Chinese Cabbage Cultivation

  • Jang, Jae-Eun;Kang, Chang-Sung;Park, Jung-Soo;Kim, Sun-Jae;Kim, Hee-Dong
    • 한국토양비료학회지
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    • 제48권1호
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    • pp.8-14
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    • 2015
  • Livestock waste compost tea is a liquid extract of compost obtained by mixing livestock compost. In this study, some chemical and microbiological characteristics of compost tea depending on the kind of raw materials used were examined, and several experiments to investigate the practical effects on Chinese cabbage cultivation were conducted. This experiment showed that livestock composts needed to be added into aerated water at the ratio between 1:100 and 1:10 (1 part compost to 10~100 parts water) to produce the high quality compost tea. Compost teas must be aerated more than 24 to 48 hours to be able to support aerobic organisms. In cultivation test with compost teas, swine manure compost teas were made by the extracting ratio of 50x, in the aerated condition for 24 hours in water and oil cake in the extracting ratio of 100x were added as supplements. Following the input of oil cake, the concentration of nitrogen and aerobic bacteria increased. Another experiment was conducted to determine the effect of different swine manure compost teas on plant growth and yield of Chinese cabbage. The fresh yield of Chinese cabbage was higher in the fertigated plots by compost tea with oil cake compared to those of N, $P_2O_5$, $K_2O$ fertilization plot with chemical fertilizer by soil test recommendation (Fert. NPK). The effect of compost tea on growth of Chinese cabbage was largely attributable to the increased number of microorganisms as well as nutrients.

An option to provide water and fertilization for rice production in alkaline soil: fertigation with slow release fertilizers (SRFs)

  • Young-Tae Shin;Kangho Jung;Chung-Keun Lee;Jwakyung Sung
    • 농업과학연구
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    • 제49권4호
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    • pp.923-931
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    • 2022
  • An increasing global population requires a greater food supply, and accordingly there is demand for enhanced production of rice, as a major crop plant that covers half of the world's population. Rice production in arid area is extremely difficult due to poor soil fertility, salinity, deficit of irrigation water, and weather conditions. The aim of the present study was to determine whether various fertilization recipes could provide a countermeasure to allow rice production while also providing soil amendment such as soil pH adjustment. The study was conducted at an experimental field of the United Arab-Emirates (UAE) from January to April, 2022. Rice seedlings (cv. Asemi, alkaline-resistant) were transplanted in plastic containers, and different types of water and nutrient managements were employed as follows: water management (flooding and aerobic for NPKs treatment group) and nutrient management (NPKs, slow release fertilizers [SRFs] and SRFs + NPK-1 treatment groups with flooding). Water and nutrient management did not show any effect on soil pH adjustment. Rice growth was significantly enhanced in the flooding compared to the aerobic condition, whereas the effect of nutrient management clearly differed among the treatment groups, with SRFs + NPK-1 showing the best results followed by SRFs and NPKs. Most of the fertilization groups markedly accumulated soluble sugars in the shoots and grains of rice plants, but concomitantly a decrease in the roots. Overall, the level of starch showed a tendency of relatively slight perturbation by fertilization. Taken together, the results indicate that soil physical structure should be preferentially amended to find the key for suitable rice production.

호기성 고율 안정조에서 빛의 조사 기간과 pH가 조류의 영양물질 제거에 미치는 영향 (Effect on Nutrients Removal of Algae in Aerobic High Rate Pond by Irradiance Period and pH)

  • 공석기;안승구
    • 한국환경과학회지
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    • 제6권2호
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    • pp.141-152
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    • 1997
  • The pilot plant had been made so as to be an association system from the various items managed to have degrees of efficiency and It have been done to consider the experimental result with irradiance period and pH influence of all major things to treatment function of Waste Stabilization Pond. The results are as following. The attained results for continuous & cyclic irradiance 1. 24L.-reactor was prior to 12L.-12D.-reactor on oxygen generation & algal production ability. 2. 24L.-reactor was prior to 12L.-12D.-reactor on nutrients removal efficiency. 3. In 24L.-reactor it maintained 5mg/L∼6mg/L, DO concent enough to a fish's survival. The attained results for pH condition 1. Oxygen generation ^ algal production in pH 4-reactor were higher than those in pH 10-reactor. 2. The acidic condition at pH 4 and alkalic condition at pH 10 did not so much affect an algal growth and nutrients removal. The attained results for whole 1. In view of the results appeared as [(NH3-N)+(NO3-N)] removal efficiency, 89.1%∼93.9% and PO4-P removal efficiency, 34.3%∼83.7% & COD removal efficiency, 88.5%∼93.9%. It is possible to treat the wastewater with starch and pH which have been known as thedifficult problem. 2. At the point of non using methanol to nitrificate NO3-N, the nutrients removal method by using an algal growth is the most economical method in the whole nutrients removal methods. 3. The nutrients removal method by using an algal growth contributes to natural ecosystem. 4. The nutrients removal method by using an algal growth is excellant in the prevention against the eutrophication.

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