• 대한환경공학회지
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• 제37권9호
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• pp.526-532
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• 2015

유기성폐수 처리공정에서 악취발생농도가 높을 것으로 예상되는 양돈분뇨 처리공정에 pellet과 stone을 충진한 생물 반응기를 도입하고 대조시설로서 생물반응기를 도입하지 않는 활성슬러지법 공정과 비교하여 반응조 운전상태, 처리수질, 악취발생농도를 측정하였다. 거품발생, 처리수 투시도 등에서 생물반응기를 도입한 반응조가 훨씬 안정적인 모습을 보였으며 BOD 제거효율도 우수하였다. 반면, 총질소(T-N), 총인(T-P) 제거효율은 두 개의 반응조가 큰 차이를 보이지 않아 방류수 수질기준을 만족시키기 위해서는 별도의 고도처리를 하여야 할 것으로 나타났다. 악취는 암모니아성 질소, 암모니아 농도, 복합악취를 기준으로 살펴본 결과 생물반응기를 도입한 공정이 활성슬러지 공정보다 적게는 4배에서 최대 24배 이상 낮게 나타나 악취원인물질 발생이 적은 것으로 나타났다. 황화수소, 메틸머캅탄, 디메틸설파이드, 디메틸디설파이드 농도는 각각의 반응조 모두 검출되지 않거나 5 ppb에 불과하였으며 두 반응조의 차이 또한 크지 않는 것으로 나타났다. 생물반응기 공정에서는 주로 Bacillus sp./ Pseudomonas sp. 종이 주를 이루고 활성슬러지 공정에서는 Bacterium sp. Chryseobacterium sp. 종이 주를 이루었다.

• 상하수도학회지
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• 제20권1호
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• pp.122-127
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• 2006

The aim of this study was to investigate the characteristics of membrane fouling caused by soluble organic materials in a membrane bioreactor process. For the removal of filterable organic materials (FOC) smaller than $1{\mu}m$, coagulants and activated carbon were added. A membrane bioreactor using a submerged $17{\mu}m$ metal sieve was operated in laboratory scale to examine the possibility of membrane fouling control. As the dosage of GAC and coagulant increased, the residual FOC concentration decreased and the permeate flow rate increased markedly. The permeate flux increased with an increased PACl addition at the range from 0 to 50 mg/l. At coagulant dosage of 27mg/l, the removal of FOC was about 46% and the flux increased to 3.5 times compared to the case without PACl addition. The permeate flux increased gradually with an increase in GAC dosage. At GAC dosage of 50mg/L, the permeate flux was about 2 times higher compared that for raw water. The particle in the range of $0.1{\sim}1.0{\mu}m$ were removed effectively by the addition of GAC and coagulant. Higher osage of GAC and coagulant, led to higher removal of FOC. A different set of experiments was also performed to investigate the effect of pretreatment on the permeation ability of MBR system using the metal sieve membrane. After 40 hours of operation, the permeate flux was about 1,000 ($L/m^2-hr$), which is 20 times higher compared to the results in literature. It is likely that combined pretreatment using coagulant and activated carbon was the most effective to resolve membrane fouling problems. Moreover, the continuous operations could be successful by applying this pretreatment method.

• Journal of Microbiology and Biotechnology
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• 제10권5호
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• pp.728-732
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• 2000

Propagation of Anagrapha falcifera nuclear polyhedrosis virus(AfNPV) was investigated using well-plates and split-flow air-lift bioreactors. In well-plate experiments, the effects of pH, cell density at a point of infection, serum concentration, DEAE-dextran, and lipid on virus propagation were all closely examined. The AfNPV titer in well-plates was optimal at pH 6.8 and $3{\times}10^6$ cells/$cm^2$. The virus titer was not dramatically affected when the fetal bovine serum concentration was reduced from 10% to 5%. The addition of cholesterol at AfNPV infection of Sf21 cells enhanced the virus titer, whereas the addition of DEAE-dextran did not improve the titer. The AfNPV titer ($3.8{\times}10^7$ $TCID_{50}/ml$) at optimized conditions for well-plate experiments was 2.5-fold higher than for the control. In bioreactor experiments, the AfNPV titer showed its maximum level at air flow rates of 20-40 ml/min. In a split-flow air-lift bioreactor, AfNPV titer ($2.3{\times}10^7\;TCID_{50}/ml$) was 1.5-fold higher than the control when the culture was at pH 6.8 and supplemented with 0.34 mM cholesterol.

• 멤브레인
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• 제31권5호
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• pp.327-332
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• 2021

멤브레인 기반의 MBRWG (Membrane Bioreactor for Waste Gas) 처리기술은 폐가스 흐름에 대한 높은 선택성을 바탕으로 효과적인 생물학적 제거를 수행할 수 있다. MBRWG에는 몇 가지 잠재적 이점이 있는데, 이 중 가장 두드러진 점은 기상과 액상이 멤브레인 양쪽으로 명확히 분리되어 액상 내 생물막의 최적제어가 용이하고 이를 통해 효과적인 생분해와 생물막의 활성화를 도모할 수 있다는 것이다. MBRWG 처리기술은 특히 xylene 같은 소수성 독성 기체 성분 제거에 유리한데 이는 소수성 기체의 물질전달속도, 독성 및 제거율이 생물막 인근의 액상흐름 및 수분제어에 민감하게 변화하기 때문이다. MBRWG 처리에 쓰이는 다양한 멤브레인 중에서 PDMS-중공사막(hollow fiber)이 가장 높은 기체 물질 전달을 제공한다고 보고되었다. Capillary 형태도 중공사막형태에 비해 비표면적은 낮지만 비교적 활발한 연구가 진행되고 있다. 소수성 기체성분 제거 외에도 기존 생물학적 폐가스 처리 장치에서 배출된 잔류 기체 혼합물이나 먼지를 제거하기 위한 후단 공정에서 멤브레인 활용을 고려할 수 있다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권6호
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• pp.331-334
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• 2002

Culture conductivity and on-line NADH fluorescence were used to measure cellular growth in plant cell suspension cultures of Podophyllum hexandrum. An inverse correlation between dry cell weight and medium conductivity was observed during shake flask cultivation. A linear relationship between dry cell weight and culture NADH fluorescence was obtained during the exponential phase of batch cultivation In a bioreactor under the pH stat (pH 6) conditions. It was observed that conductivity measurement were suitable for biomass characterisation under highly dynamic uncontrolled shake flask cultivation conditions. However, if the acid/alkali feeding is done for pH control the conductivity measurement could not be applied. On the other hand the NADH fluorescence measurement allowed online-in situ biomass monitoring of rather heterogenous plant cell suspension cultures in bioreactor even under the most desirable pH stat conditions.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.181-184
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• 2000

The cooling rate of a bioreactor was measured to estimate the heat generation by microbial cultivation production. The estimated heat production was calculated from the varying temperature of cooling water. It was used for monitoring growth and specific metabolic events for microbial cultivations. Metabolic heat measured was also adopted for a control parameter for fed-batch cultivation.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2003년도 식물바이오벤처 페스티발
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• pp.113-113
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• 2003

• 원예과학기술지
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• 제33권4호
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• pp.585-590
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• 2015

본 실험은 생물반응기를 이용한 딸기 조직배양묘 대량증식 시 flurprimidol 을 처리하여 순화율을 향상시키고자 실시하였다. Flurprimidol 을 0, 0.1, 0.5, 1.0 및 $2.0mg{\cdot}L^{-1}$의 농도로 6주동안 처리하여 생육조사한 결과, flurprimidol을 첨가한 처리구의 생장량이 대조에 비해 감소하였고, 처리농도가 증가할수록 생장억제효과가 크게 나타났다. 초장은 대조가 7.9cm인 것에 비해 flurprimidol 처리는 2.2-3.7cm 범위로 매우 짧아졌다. 뿌리수는 대조가 51.8개/주에 비해 flurprimidol 처리가 11.6-34.2개/주 범위로 감소하였다. 뿌리길이는 대조가 4.36cm에 비해 flurprimidol 처리는 0.88-3.08cm 범위로 크게 짧아졌다. 그러나 액아수는 flurprimidol $2.0mg{\cdot}L^{-1}$ 처리를 제외하고 모든 처리구에서 대조의 8.6개/주에 비해 많이 발생하였을 뿐만 아니라 액아수가 증가할수록 그에 따라 잎수도 증가하였다. Flurprimidol $1.0mg{\cdot}L^{-1}$ 처리 시 뿌리가 부패하여 지하부 발달이 불량하였다. Flurprimidol $1.0mg{\cdot}L^{-1}$와 $2.0mg{\cdot}L^{-1}$ 처리를 제외한 모든 처리의 순화율은 100%로 대조에 비해 23.3% 향상되었다. 순화 4주 후, flurprimidol $0.1mg{\cdot}L^{-1}$ 처리는 생체중을 제외한 지상부 및 지하부 생육이 대조와 비슷하게 회복되었다. 따라서 생물반응기를 이용한 딸기의 조직배양묘 대량 증식 시 순화율 향상을 위한 적정 flurprimidol 농도는 $0.1mg{\cdot}L^{-1}$였다.

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.513-517
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• 2010

A thermostable trehalose synthase (TtTSase) from Thermus thermophilus HJ6 was immobilized on chitosan activated with glutaraldehyde. The yield of immobilization was evaluated as 39.68%. The optimum pH of the immobilized enzyme was similar to that of the free enzyme. However, the optimal temperature ranges were shifted by about $4^{\circ}C$ owing to better thermal stability after immobilization. The half-life of heat inactivation for free and immobilized enzymes was 5.7 and 6.3 days at $70^{\circ}C$, respectively, thus showing a lager thermostability of the immobilized enzyme. When tested in batch reaction, the immobilized enzyme retained its relative activity of 53% after 30 reuses of reaction within 12 days, and still retained 82% of its initial activity even after 150 days at $4^{\circ}C$. A packed-bed bioreactor with immobilized enzyme showed a maximum yield of 56% trehalose from 100 mM maltose in a continuous recycling system (bed volume: 10 ml) under conditions of pH 7.0 and $70^{\circ}C$.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.173-176
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• 2000

A neural network based controller (NN controller) was studied for the control of ammonia concentrations in biological processes. An ammonia FIA has been employed to on-line monitor the concentrations of ammonia in a bioreactor. The optimal neural network structure was investigated by computer simulation and found to be a 3(inputlayer)-2(hidden layer)-1(output layer). The NN controller had advantage over the PID controller, even though the former is more time consuming. The 3-2-1 NN controller has been used to control the ammonia concentrations in a simulated bioprocess and also in a real cultivation process of yeast, and its performance were investigated.