• Journal of Microbiology and Biotechnology
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• 제15권1호
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• pp.1-6
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• 2005

Optimal criterion for the scale-up production of schizophyllan, a fungal polysaccharide secreted by Schizophyllum commune, was investigated. For the production of the polysaccharide in a 150-l bioreactor, the culture conditions optimized in a 15-l bioreactor were applied to a 150-l bioreactor with scale-up process, by changing impeller speed and airflow rate. The optimized impeller speed in the 15-l bioreactor was 50 rpm in a technical medium based on barley. For establishment of the scale-up process, 3 kinds of criteria were used while the gas throughput number was kept constant, as follows; constant volume-related power input, constant tip speed of stirrer, and constant Reynolds number. In the 150-l bioreactor, the highest values for the maximum specific growth rate (1.17/day) and productivity (0.63 g/L${\cdot}$day) were achieved in the culture condition from constant volumerelated power input criterion.

• Environmental Engineering Research
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• 제19권3호
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• pp.293-298
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• 2014

An anaerobic photosynthetic treatment process utilizing purple non-sulfur photosynthetic bacteria (PNSB) was applied to the recovery of organic carbon from food processing wastewater. PNSB cells, by-product from the treatment, have high nutrition such as proteins and vitamins which are a good alternative for fish feed. Effects of light source on performance of anaerobic photosynthetic process were investigated in this study. Two bench-scale photo-bioreactors were lighted with infrared light emitting diodes (LEDs) and tungsten lamps covered with infrared transmitting filter, respectively, aiming to supply infrared light for photosynthetic bacteria growth. The photo-bioreactors were operated to treat noodle-processing wastewater for 323 days. Hydraulic retention time (HRT) was set as 6 days. Organic removals in the photo-bioreactor lighted with infrared LEDs (91%-95%) was found higher than those in photo-bioreactor with tungsten lamps with filter (79%-83%). Biomass production in a 150 L bench-scale photo-bioreactor was comparable to a 8 L small-scale photo-bioreactor in previous study, due to improvement of light supply efficiency. Application of infrared LEDs could achieve higher treatment performance with advantages in energy efficiency and wavelength specifity.

• 멤브레인
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• 제7권4호
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• pp.175-182
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• 1997

혐기-호기의 생물반응조 공정과 막분리 공정을 조합한 막-생물반응조 공정을 이용하여 염색폐수 중의 난분해성 물질들을 제거하였다. 염색폐수 원수를 직접 막분리공정에 적용한 결과 심각한 fouling을 초래하였다. 반면 생물반응조로 1차 처리한 후 막분리공정에 적용한 경우 생물반응조가 막의 오염원을 상당부분 제거하여 fouling현상이 현저리 감소하였으며, 막의 수명도 연장시킬 수 있었다. 염색폐수의 처리효율 및 fouling현상은 막의 기공 크기나 구조보다는 막의 재질에 더욱 의존함을 확인하였다. 중공사막 module의 사용 방법 및 중공사막 내부의 유속에 따라서 제거효율 및 투과유량이 변화하였다. 생물반응조나 막분리 단독공정보다 두공정을 조합한 공정이 보다 효과적으로 염색폐수 처리능력을 보였다.

• 한국물환경학회지
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• 제18권2호
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• pp.141-150
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• 2002

Two-stage membrane bioreactor using submerged hollow fiber membrane was applied in laboratory scale to treat nitrogen and phosphorus of domestic wastewater. Alum as the flocculant and adsorbent was added into the anaerobic basin of two-stage membrane bioreactor and mixed liquid of aerabic basin was recycled to the anaerobic basin for the purpose of nitrogen removal. Experiment was carried out to find removal efficient of phosphorous and nitrogen components in the mixed liquid, and the stability of the permeate flux and pressure of two-stage membrane bioreactor. In case of alum was added as the flocculant and adsorbent into the anaerobic basin, soluble phosphorus removal efficient was relatively higher and total permeate resistance(Rtot) was more increased out nitrogen removal efficient was lower as the result of lack of alkalinity and insufficient nitrification process than the case of alum was not added.

• KSBB Journal
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• 제6권2호
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• pp.129-133
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• 1991

This study is to investigate the kinetics of anaerobic process, the effect of mass transfer on process, and the characteristics of the conventional anaerobic bioreactor, and develop new high efficiency bioreactor. In the new bioreactor wastewater containing highly concentrated organic materials, was treated without diluting wastewater. In this experiment the high COD removal rate (about 88%) and gas production(about 200l/d) was showed with short residence time(1.5 day). This performance is about 10 times as large as the conventional reactor.

• Journal of Microbiology and Biotechnology
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• 제19권4호
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• pp.346-350
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• 2009

Although salt is known to influence the performance of nitrification significantly, it has not been well reported on how salt affects ammonia-oxidizing bacterial(AOB) community compositions and dynamics in wastewater treatment bioreactors. In this study, these questions were evaluated in a full-scale bioreactor treating saline wastewater. Clone library analysis for the ammonia monooxygenase subunit A gene revealed that AOB belonging to the Nitrosomonas europaea and the N. oligotropha lineages inhabited in the bioreactor. Terminal restriction fragment length polymorphism analysis for monthly samples demonstrated a fluctuation pattern among AOB populations, although AOB within the N. europaea lineage were dominant during the test period. Correlation analysis between patterns of terminal restriction fragments and environmental variables suggested that sodium, chloride, and sulfate were less important; rather, temperature was the most significant factor affecting the AOB community in the bioreactor.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.145-148
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• 2000

Large-scale resolution of epoxides by the yeast Rhodotorula glutinis was demonstrated in an aqueous/organic two-phase cascade membrane bioreactor. Due to the chemical instability and low solubility of epoxides in aqueous phases, an organic solvent was introduced into the reaction mixture in order to enhance resolution of epoxide. A cascade hollow-fiber membrane bioreactor was used (i) to minimize the toxicity of organic solvents towards the epoxide hydrolase of Rhodotorula glutinis, and (ii) to remove inhibitory amounts of formed diol from the yeast cell containing aqueous phase. Dodecane was selected as a suitable solvent and 1,2-epoxyhexane as a model substrate. By use of this membrane bioreactor, highly concentrated (0.9 M in dodecane) enantiopure (>98% ee) (S)-1,2-epoxyhexane (6.5 g, 30% yield) was obtained from its racemic mixture.

• 한국환경과학회지
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• 제8권4호
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• pp.479-483
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• 1999

Nitrifier consortium immobilized in polyvinyl alcohol was used for the removal of ammonia nitrogen from synthetic aquaculture water in the airlift bioreactor. At the aeration rate fo 0.15 vvm and bead packing volume fraction of 20%, airlift bioreactor was operated effectively for a removal of ammonia nitrogen and for a stability of operation. Ammonia nitrogen removal rate by airlift bioreactor was continuously increased with decreasing hydraulic residence time. At the HRT(hydraulic residence time) of 0.3 hour, ammonia nitrogen removal rate was 84.3 g/$m^3$.d and the highest ammonia nitrogen removal rate was 130.8 g/$m^3$.d when HRT was 0.1 hour.

• Journal of Microbiology and Biotechnology
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• 제4권3호
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• pp.200-203
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• 1994

Spodoptera frugiperda IPLB-SF-21-AE cells were cultivated in a spin-filter bioreactor with continuous perfusion for the recombinant $\beta$-galactosidase production. At the perfusion rate of 0.06 $hr^{-1}$, the maximum cell density of insect cells in this bioreactor system reached 3.5$\times$$l0^6$ viable cells/ml using the Grace media containing 5% FBS and 0.3% Pluronic F-68. The recombinant $\beta$-galactosidase production of 8, 100 units per reactor volume was also achieved at this perfusion rate.

• Journal of Microbiology and Biotechnology
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• 제14권3호
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• pp.435-441
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• 2004

A drum bioreactor was used for the treatment of sandy soil contaminated with three kinds of aromatic compounds (phenol, naphthalene, and phenanthrene), and its performance was evaluated in two different operation modes; intermittent and continuous rotation of drum. When the drum bioreactor was operated with one rotation per day, the microbial growth was relatively low, and most of the compounds remaining in soil, except naphthalene of 90 mg/kg dry soil, disappeared mainly due to volatilization. In contrast, when the drum was continuously rotated at 9 rpm (rotation/min), the number of microorganisms was drastically increased and nitrate was consumed for growth as a nitrogen source. Phenol and phenanthrene were removed at rates of 56.7 mg/kg dry soil/day and 3.2 mg/kg dry soil/day, respectively.