• Biotechnology and Bioprocess Engineering:BBE
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• 제7권5호
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• pp.289-294
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• 2002

Cellulose production by Acetobacter pasteurianus was investigated in static culture using four bioreactors with silicone rubber membrane submerged in the medium. The shape of the membrane was flat sheet, flat sack, tube and cylindrical balloon. Production rate of cellulose as well as its yield on consumed glucose by the bacteria grown on the flat type membranes was approximately ten-fold greater than those on the non-flat ones in spite of the same membrane thickness. The membrane reactor using flat sacks of silicone rubber membrane as support of bacterial pellicle can supply greater ratio of surface to volume than a conventional liquid surface culture and is promising for industrial production of bacterial cellulose in large scale.

• 한국환경과학회지
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• 제8권2호
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• pp.177-182
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• 1999

Nitrifier consortium entrapped in Ca-alginate bead were packed into aerated packed bed bioreactor and non aerated packed bed bioreactor and the performances of two bioreactors were evaluated for the removal of ammonia nitrogen from synthetic aquaculture water. Total ammonia nitrogen(TAN) removal rate was decrease in aerated packed bed bioreactor below 0.3hr of hydraulic residence time(HRT), but increased in non aerated packed bed bioreactor until 0.5hr of HRT. At HRT of 0.05hr, TAN removal rate of non aerated packed bed bioreactor was about 335g TAN/㎥/day and the optimum ratio of packing height and inside diameter of reactor (H/D) was 4. The performance of two bioreactors indicated that non aerated packed bed bioreactor was better than aerated packed bed bioreactor in ammonia removal from synthetic aquaculture water.

• 한국미생물·생명공학회지
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• 제17권6호
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• pp.624-628
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• 1989

A study on the citric acid production using Saccharomycopsis lipolytica (NRRL Y7576) was carried out in shake-flasks, air-lift and membrane recycle bioreactors. The cells entrapped in Ca-alginate beads were used in shake-flasks and air-lift reactor. Repeated batch fermentation in shake-flasks was successfully performed for 34 days and resulted in a yield of 54%. Increased yield (63%) was obtained in the air-lift reactor operation using nitrogen deficient medium (NDM). In the membrane recycle bioreactor operation, the maximal dry cell mass concentration was 39 g/1 at a dilution rate of 0.02 h$^{-1}$ and the yield with NDM was higher than that with growth medium. In addition, the yield and volumetric productivity with pure oxygen supply were greatly improved compared with those with air supply.

• Membrane and Water Treatment
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• 제11권1호
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• pp.31-39
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• 2020

Anaerobic membrane bioreactor (AnMBR) treatment has been widely studied in recent years because of the potential for production of bio-energy from wastewater and energy-positive operation of wastewater treatment plants. Several AnMBR systems, including those that incorporate ceramic membranes, take advantage of enhanced water permeability and low membrane fouling potentials. Given that differences in the ceramic membranes may influence the results of AnMBR studies, relevant details are discussed in this review, which focuses on the profiles of common ceramic membranes used in AnMBR, treatment and filtration performances of different anaerobic ceramic membrane bioreactors (AnCMBRs), and the membrane fouling mitigation methods available for effective AnCMBRs operation. The aim of this review is to provide a comprehensive summary of AnCMBR performance, feed wastewater characteristics, operating conditions, and the methods available for effective fouling mitigation.

• 한국미생물·생명공학회지
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• 제22권3호
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• pp.304-308
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• 1994

A suitable culture method and bioreactor type for itaconic acid production were chosen by comparing the maximal concentration of itaconic acid produced in various systems. In batch culture, the maximal concentration of itaconic acid produced in a bubble column reactor was about 5% greater than that produced in stirred-tank or external-loop airlift reactor. These results were thought to be due to lower shear force and higher mass transfer efficiency in a bubble column reactor in comparison with other reactors. Moreover, the fed-batch mode in a bubble column was found to be a suitable one, producing about 25% higher concentration of itaconic acid compared to batch mode.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 1999년도 제39회 춘계학술발표대회
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• pp.52.2-52.2
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• 1999

• 한국물환경학회지
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• 제25권2호
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• pp.329-334
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• 2009

Bacterial numbers, such as endospore-formers, and treatment efficiencies were investigated for Rotating Activated Bacillus Contactors (RABC) and other advanced wastewater treatment processes including anaerobic-anoxic-oxic (A2O), sequencing batch reactor (SBR) and biological aerated filter (BAF). Endospore-forming bacterial numbers in the RABC showed 129-fold higher levels than those of the existing advanced systems. RABC process demonstrated the highest bacterial numbers in its bioreactors (paired t-test, p<0.01). RBC biofilms and aeration tanks of the RABC system showed 131- and 476-fold higher than other existing advanced processes, respectively. Mean treatment efficiencies of the existing systems were 83.5% for chemical oxygen demand (COD), 59.1% for total nitrogen (TN) and 76.8% for total phosphorus (TP). However, RABC process removed 96.9% for COD, 96.9% for TN and 91.9% for TP for highly concentrated food wastewater (COD>1,500 mg/L, TN>150 mg/L, TP>50 mg/L). Treatment efficiency was significantly reduced when the numbers of Bacillus genus in the bioreactors decreased below $10^6CFU/mL$. The automated RABC (A-RABC), in which dissolved oxygen concentrations are automatically controlled, showed higher treatment efficiencies compared to the RABC process. The RABC system maintained sufficient bacterial numbers for the effective treatment of highly concentrated food wastewater. Moreover, final effluent was in agreement to water quality standards.

• KSBB Journal
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• 제13권3호
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• pp.238-243
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• 1998

양어장 순환수 속의 암모니아성 질소의 제거를 위한 Ba-alginate 와 Ca-alginate 반응기는 0.6시간의 수력학적 체류시간에서 51.0, 52.6 g $NH_3-N/m^3/day$의 거의 유사한 암모니아성 집소의 제거속도릎 나타내었다. Ca-alginate를 이용한 합성양어장수 속의 암모니아성 짖소의 제거 실험에서 본 반응기의 암모니아성 짐소의 제거속도는 수력학적 체류시간이 0.3시간인 지점에서 82.0 g $NH_3-N/m^3/day$로 서 최고의 재거속도릎 나타냈으며 이때 암모니아 제거율은 48% 이었다. 수중의 암모니아의 농도가 2mg/L 정도의 범위에서는 반응기 내에 주입되는 공가량을 0.1 vvm 으로 공급하더라도 용존산소 농도를 7.0 - 5.6 g/m3로 유지 할 수 있었으므로 질화에 필요한 용존산소량을 충분히 유지할 수가 있는 것으로 나타났으며 pH 는 7.2 - 7.9의 범위플 유지할 수가 있어서 pH 변화에 따른 위 해 요소는 없는 것으로 나타났다.

• KSBB Journal
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• 제14권5호
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• pp.534-538
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• 1999

식물세포배양을 위한 bioreactor의 운전조건 최적화를 위해 Nicotiana tabacum 현탁세포를 model system으로 bioreator의 종류, 교반기의 형태, 그리고 통기량에 따른 세포생장을 관찰하였다. Bioreactor로는 stirred tank bioreactor과 airlift bioreactor를 사용하였으며 두가지 배양기 모두 flask에서의 생장보다 낮은 생장을 보였으며 stirred tank bioreactor보다는 airlift bioreator에서 높은 세포농도를 얻을 수 있었다. 교반기의 종류에 따른 세포의 생장은 큰 차이가 없었으나 hollowed paddle impeller를 사용하였을 경우에는 배양기간 동안 세포의 크기가 작게 유지되었다. 통기량을 0.30 vvm으로 유지하는 경우에 가장 좋은 세포생장을 관찰할 수 있었으며 1.0 vvm이상의 통기량에서는 과도한 foam의 형성과 세포의 갈색화 현상을 보이며 세포의 생장도 저해되었다. 또한 통기량이 증가할수록 세포크기지수가 감소하는 결과를 보였다.

• Journal of Plant Biotechnology
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• 제31권3호
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• pp.249-253
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• 2004

생물반응기의 형태에 따른 인삼부정근의 생장과 ginsen-side의 생산능력에 대하여 조사한 결과, 원형의 상부와 하부에 5 cm의 bubble column을 가진 bulb type bubble bioreactor (BU)에서 건물중은 41.92 g으로 가장 많이 증가하였으며, cylindric tube bioreactor (CT)에서 건물중이 38.55g으로 가장 낮게 나타났다. 이들 두 생물반응기의 초기 kLa 값은 BU 생물반응기에서 6.98 h$^{-1}$로 가장 높게 측정되었고, 반대로 bubble column이 없는 CT 생물반응기에서 5.25 h$^{-1}$으로 가장 낮게 측정되었다. 그러나 이와 같은 초기 kLa값의 차이는 부정근내의 이차대사산물인 ginsenoside의 함량에는 영향을 주지 않는 것으로 나타났다. 또한 BU 생물반응기에서 bubble column의 길이를 기존의 5 cm에서 10 cm로 연장시켰을 때, 초기 kLa값이 6.52 h$^{-1}$에서 7.80 h$^{-1}$로 증가하면서 인삼부정근의 생장을 42.13 g에서 50.30 g으로 약 16% 증가시킨 것으로 나타났다.