• 한국유변학회:학술대회논문집
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• 한국유변학회 2001년도 Australian-Korean Rheology Conference 2001
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• pp.157.2-157
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• 2001

• 한국미생물·생명공학회지
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• 제18권5호
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• pp.525-529
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• 1990

식물세포인 Lithospermum erythrorhizon을 교반 반응기와 calcium alghinate에 고정화된 상태로 충전층 반응기에서 n-hexadecane으로 동시 추출하면서 shikonin을 생산하여 각각의 생산성을 비교하였다. 교반 반응기에서 shikonin의 비생산과 부피생산성은 각각 1.5mg shikonin/g cell과 400$\mu g$ shikonin/(L.day)였고 충전층 반응기에서는 가각 2.0mg shikonin/g cell과 2857 $\mu g$ shikonin/(L.day)였으며 이는 각각 교반 반응기에 비하여 1.3, 7.1배 높은 것이다. 충전층 반응기에서 shikonin의 생산성이 높은 것은 calcium alginate 입자에 세포가 고농도고 축적되어 단위 반응기 부피당 세로의 부하 능력이 높고 또한 세포가 서로 접촉하기가 쉽고 고정화 입자내의 환경이 세포가 분화하기에 좋은 조건을 형성하기 때문인 것으로 사료된다.

• KSBB Journal
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• 제26권4호
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• pp.328-332
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• 2011

Ethanol production using glycerol as a carbon source was performed by Enterobacter aerogenes immobilized on calcium alginate beads. To improve the ethanol production, the optimal conditions such as loading amount of immobilized cells and glycerol concentration were investigated. The optimal loading amount of immobilized cells and glycerol concentration were 10 mL of calcium alginate bead and 10 g/L, respectively. Consequently, glycerol consumption rate, ethanol concentration and yield were 0.32 g/$L{\cdot}h$, 3.38 g/L and 0.43 g/g on the batch production, respectively. Continuous production of ethanol was successfully achieved using two types of immobilized cell reactors (continuous stirred tank reactor and packed bed reactor) from 10 g/L of glycerol. In the continuous stirred tank reactor, glycerol consumption, ethanol concentration, specific productivity and yield were 9.8 g, 4.67 g/L, 1.17 g/$L{\cdot}h$, 0.48 g/g, respectively. The concentration of produced ethanol was 38-44% higher comparison to batch fermentation, and continuous stirred tank reactor showed better performance than packed bed reactor.

• Journal of Microbiology and Biotechnology
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• 제10권1호
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• pp.75-80
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• 2000

An improved method of refolding recombinant human proinsulin from E. coli was presented. It was based on a two-stage stirred tank reactor in which denatured proinsulin-s-sulfonate was mixed instantaneously with a reaction buffer in the first stage reactor, and then fed to the second stage reactor. The mixture was stirred further for a total of 30h in the second stage reactor. In this system, unfavorable effects present due to the increase in reaction volume and protein concentration for protein refolding, which becomes significant in a large-scale operation, were avoided. Refolding yields of over 80% was obtained for achieving reaction volume of upto 50 l at protein concentration of 1 mg/ml. The optimum urea concentration was 1M. Refolding yield at the 1-1 reaction volume and protein concentration of 0.5mg/ml was increased about 2.5-fold, compared to that in a batch reactor. By increasing protein concentration in a two-stage refolding reaction, the cost for insulin production could be reduced, therefore, making this process economical.

• 유기물자원화
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• 제13권4호
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• pp.128-135
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• 2005

본 연구에서는 CFSTR(Continuous-flow Stirred-Tank Reactor) 형식의 반응조에 담체가 채워진 호기-혐기조합 공법에 따른 질산화 및 탈질화에 관한 효율의 증대와 유입수 및 침전조 상등액의 유량대비를 조절 하므로써 질소제거의 효율 증대에 관한 방법을 모색하고자 하였다. 탈질조 내의 탈질효율에 비례하여 포기 반응조 내의 질산성 질소 농도를 산출하고자 유입수와 침전조 내에서의 상등액을 탈질조로 반송하여 유입하고 유입수와 반송되는 침전조 상등액 유입의 유량대비를 통하여 최종적으로 반응조에 대한 질소제거의 효율을 파악하고자 하였다. 적절한 유량대비를 이용하였을 때 탈질조 내의 필요한 탄소원의 공급이 유입수로 통해 이루어지는 것으로 판단되어지며, 외부탄소원의 주입 없이 유입수 만으로도 완벽하게 탈질이 이루어지는 것을 확인 할 수 있었다. 하지만 유입수와 침전조 상등액의 유량대비에서 침전조 상등액의 유량비가 커지면 커질수록 유입수내의 탄소원의 유입이 줄어들기 때문에 이에 대한 탄소원의 농도에 대한 산정이 중요하다고 생각된다.

• KSBB Journal
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• 제14권3호
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• pp.365-370
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• 1999

To optimize the culture conditions for Beauveria bassiana 726, the effects of culture medium, pH, and temperature on mycelium and spore production were investigated. The optimum temperature and pH for the cultivation of B. bassiana 726 were 28 $^{\circ}C$ and 5.0, respectively. The optimized medium was composed of 1.0~2.0% total sugar from molasses, 0.5% corn steep liquor and 0.05% KH$_2$PO$_4$. In the cultivation of B. bassiana 726 with the optimum medium, the specific growth rate and substrate utilization were well-fitted with the proposed kinetic model in the shake flask and stirred tank reactor. When the fed-batch cultivation using carbon suorce, nitrogen source, and mineral salt as a feeding medium was compared with batch cultivation in stirred tank reactor, mycelium (12.7 g/L) and spore production (5.4$\times$$10^8/mL$) were enhanced up to 110% and 85%, respectively.

• 대한환경공학회지
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• 제38권1호
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• pp.25-33
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• 2016

본 연구에서는 수처리 공정에 적용하고 있는 CSTR 반응조를 대상으로 유입 유량이 다양하게 변동하는 경우 반응조 내부 수리 거동을 조사하고자 하였다. 유입 유량의 변동은 설계 유량 대비 10~100%까지 변화시켰으며, 각 경우를 CFD 기법을 이용하여 transient 상태의 추적자 실험을 모의하였으며, 모사 결과로부터 2차 정보를 추출하여 수리 거동 지표를 계산하여 유입 유량과 수리거동의 관계를 면밀히 조사하였다. 그 결과, 유입 유량이 증가할수록 Modal index와 ${\beta}$값이 증가하는 거동을 보였으며 Morrill index는 유입 유량과의 관계에서 국부적인 극소값을 가지는 유입 유량이 두 곳 나타났는데 각각 설계 유량의 20%되는 지점과 40%가 되는 지점이었다. 두 극소값이 나타나는 유입 유량보다 유량이 증가하면 다시 Morrill index가 증가하는 현상을 보여 이상적인 CSTR 반응조에 근접하는 것으로 나타났다.

• 대한화학회지
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• 제6권2호
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• pp.130-132
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• 1962

A new method of evaluating the mixing time in the continuous flow stirred tank is herein proposed. Experimental results to test the concept are also presented.The mixing time is defined as the time interval between the injection of a slug of an electrolyte solution into the tank and the moment at which an essentially straight line begins on a plot of the conductivity of effluent versus time.The proposed method of measuring the mixing time is valid even for the low mixing time (5 seconds) and the results obtained agree well with previous work, where the mixing time measurements were carried out by the injection of a dye into the feed stream.

• Environmental Engineering Research
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• 제9권1호
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• pp.13-22
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• 2004

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.647-651
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• 1987

Yeast biomass in a biological continuous stirred tank reactor was controlled with an APPLE II microcomputer using adaptive control theory of bilinear systems. The controller used is as simple as a PID controller, but required less information. Cell concentration was well controlled by adjusting the inlet flow rate following the algorithm.