• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.309-309
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• 2011

지구온난화와 도시기후 변화에 대응하기 위해 자연의 생태적 기능을 복원하고 환경에 대한 오염부하를 저감하여 도시 환경의 건강성과 지속성을 높이기 위해 도심 내 물순환시스템(urban water circulating system)의 구축이 요구된다. 즉, 물순환시스템을 활용하여 도심 내 다양한 수원(생태하천/호수 유지용수, 하수처리수, 우수, 지하수 등)을 네트워크 및 통합 관리하여 도시 내 물순환의 건전성과 수자원의 재이용률을 향상시킬 수 있다. 이를 위해서 연중 발생량이 일정하고 막대한(66.4억톤/년, 2009년 기준) 하수처리수 방류수는 고도처리를 통해 수질이 양호하며 안정적인 대체 수자원으로 고려된다. 또한, 하수처리수의 재이용은 공공수역으로 배출되는 오염부하량의 총량 삭감 및 상수사용량의 절감과 수자원을 효율적으로 이용한다는 면에서 최근 재이용 사례가 증가하고 있는 추세이다. 그러나, 도심 내 친수공간(생태하천/호수)은 저류수량에 비해 유입수량이 적어 체류시간이 비교적 장시간이고, 이로 인해 부영양화가 쉽게 발생해 수질이 악화된다. 따라서, 본 연구에서는 하수처리수 재이용수를 도심 내 친수공간의 유지용수로 활용 시, 수질정화공정(응집 후 여과, 응집 후 여과+한외여과, 응집 후 여과+한외여과+역삼투 공정)이 친수공간 내 조류성장에 미치는 영향을 파악하기 위해, 하수처리수 재이용수 pilot plant의 수질정화공정별 유출수를 활용해 M. aeruginosa를 시험조류로 조류성장(growth kinetics)을 조사하였다. 조류는 $5\times104$ cells/mL의 초기 농도로 접종하여 배양하였으며, 조류성장에 직접적인 제한인자인 용존반응성인의 농도에 따른 성장속도를 Monod와 변형 Monod Kinetics를 이용해 반포화상수(Ks)와 최대 성장속도(${\mu}$max)를 산정하였다. 실험결과, 역삼투 공정을 제외한 다른 수질정화공정은 비록 영양염류가 80~90% 이상 제거되어 수계의 화학적 성상이 변하였으나 조류성장역학의 변화는 통계학적 (p=0.05)으로 유의할만한 수준은 아닌 것으로 판명되었다. 또한, 수리학적 체류시간이 2주 이상이 될 경우, 역삼투 공정을 제외한 수질정화공정 별 유출수에서는 조류의 과다성장으로 인해 부영양화가 발생하는 것으로 판명되었다. 결론적으로 하수처리수 재이용수를 친수용수로 활용시, 조류성장을 방지하기 위하여 용존반응성인의 농도를 중점적으로 관리하는 수질정화공정 및 유지용수 공급방안을 고려해야하는 것으로 판단된다.

• The Korean Journal of Mycology
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• v.27 no.4 s.91
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• pp.304-311
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• 1999

Batch kinetics during the exo-polysaccharide (EPS) fermentation of Ganoderma lucidum was investigated as a function of different substrates (glucose and starch), substrate concentration $(1{\sim}7%,\;w/v)$ and subculture (3 times). Logistic model for mycelial growth fitted the experimental data better than Monod and two thirds power model. The Luedeking-Pirt equation was adequate to fit the kinetic data of product formation and substrate consumption. The EPS production was strongly non-growth associated, although it was mixed type. The product formation and sustrate consumption by growth associated mechanism decreased as the concentration of glucose increased, while those of the non-growth associated mechanism increased. However, starch medium increased the growth associated and non-growth associated substrate consumption indicating higher availability of substrate. Also, batch culture in starch medium showed the higher specific growth rate and stability during subculture than those in glucose medium. In conclusion, the enhanced EPS production and stability in the subculture was found to be remarkably improved by use of starch as sole carbon source in medium. The maximum mycelium dry weight and EPS production of 9.463 and 10.410 g/l, respectively, were obtained after shake culture of 7 days at $30^{\circ}C$ from the media containing 7% starch.

• Journal of environmental and Sanitary engineering
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• v.15 no.1
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• pp.39-45
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• 2000

The purpose of this study was conducted to indentified the fixing quality of $CO_2$, the most important greenhouse effect gas, by microalgae Chlorella ellipsoidea in batch test apparatus. The glass flask of $1.4{\ell}$ culture media which was saturated with 99.99% pure $CO_2$ gas was setted water bath of $25^{\circ}C$, 5000Lux, and seeded 100$m\ell$ algae liquid. We checked the change of inorganic carbon concentration and algae population with time in culture media. The result were next: the growth of algae population relied on aquatic IC(inorganic carbon) concentration. And the pH was increased with decrease of IC concentration. The growth of algae population had positive correalation with $CO_2$ concentration, and the coefficient of correlation was 0.982. The specific growth rate($\mu$) of Chlorella ellipsoidea was 1.104/d, the maximum specific growth $rate({\mu}_{max}$) of 9.21/d, and helf velocity constant($K_s$) of $259mg/{\ell}$ by Monod equation.

• Microbiology and Biotechnology Letters
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• v.13 no.1
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• pp.33-39
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• 1985

The effects of initial concentration, flow rate, and recycle ratio on the removal efficiency of phenol were studied in a tapered fluidized bed reactor packed with activated carbon which was attached with Candida tropicalis. The optimum conditions of Candida tropicalis were showed that pH was 7.0 and temperature was $30^{\circ}C$, and the specific growth rate of Candida tropicalis was satisfied with the Monod equation up to 500 mg/L of phenol, and beyond it the inhibition of substrate was found. According to the increases of initial concentration and flow rate, the removal efficiency was decreased, as the recycle ratio was increased, the removal efficiency was increased. In the case of flow rate of 10mL/sec and the recycle ratio of 2, the removal efficiency was 90% above for the all of initial concentration. The removal rate of phenol was the first order reaction in this system, and the rate equation of reaction was as follows.

• Environmental Engineering Research
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• v.22 no.4
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• pp.417-425
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• 2017

Indonesia is known as the largest oil palm producer in the world. However, along with the production, it generates wastes and pollution that caused the environmental problem in surrounding areas. Previous researchers reported that the high palm oil mill effluent (POME) concentration inhibited microalgae growth. However, the inhibition factor was not clearly explained by using kinetic model. This study presents kinetic models of Botryococcus braunii (B. braunii) cultivated on POME wastewater under different turbidity condition. Results showed that the growth model of Zwietering was closely suitable with experimental results. It was found that B. braunii was able to consume organic carbon from the POME wastewater on the logarithmic model. A modified kinetic model of Monod Haldane described the influence of turbidity and chemical oxygen demand on the cultivation. Turbidity of POME medium inhibited the growth rate at KI 3.578 and KII 179.472 NTU, respectively. The Lipid (39.9%), and carbohydrate (41.03%) were found in the biomass that could be utilized as biofuel source.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.3
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• pp.329-338
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• 2006

The research aims to provide the basic data for practical applications by correlating the bio-kinetic coefficients with the load of recalcitrant organic matter in box-mill wastewater. The activated sludge process was employed to a Wastewater disposal plant in an industrial setting, increase of consequently leading to the organic load. The parameter values derived by Monod-kinetic analysis were as follows:specific substrate removal rate $K_{max}=0.17day^{-1}$, half saturation constants $K_s=60.37mg/l$, decay coefficient $K_d=0.142day^{-1}$, microbial yield coefficient y = 0.388mg/mg, and max specific growth rate ${\mu}_{max}=0.006day^{-1}$. In view of biodegradability, the $TCOD_{Mn}/TBOD_5$ ratios of inflow and outflow were 1.07 and 1.41, and the $SCOD_{Mn}/SBOD_5$ ratios of inflow and outflow were 1.10 and 1.50, respectively. The higher $TCOD_{Mn}/TBOD_5$ ratio of outflow indicated that metabolites of a microorganism have accumulated in the cells.

• Journal of Industrial Technology
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• v.3
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• pp.33-38
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• 1983

The effect of various environmental conditions on the growth kinetics of Zymomonas mobilis were studied and the kinetic parameters were evaluated. The value of ${\mu}m$ was $0.45hr^{-1}$ and Ks was 0.23 g/L. Inhibition of growth at high glucose concentration was found to follow the threshold substrate inhibition. Threshold substrate concentration was 102 g/L and substrate inhibition constant was 196 g/L. The effects of yeast extract concentrations were found to follow the Monod equation. ${\mu}m$ value was $0.45hr^{-1}$ and Ks was 0.3 g/L at 20 g/L of glucose and $0.24hr^{-1}$ and 0.24 g/L respectively at 200 g/L of glucose. The optimum temperature was found to be $35^{\circ}C$ and the activation energy of growth was 7.7 Kcal/mole below $35^{\circ}C$ and -29 Kcal/mole above $35^{\circ}C$.

• KSBB Journal
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• v.6 no.1
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• pp.85-90
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• 1991

Experiments of alcohol fermentation of the yeast,K. fragi1is CBS 1555 were performed to obtain the following results. In these experiments, the initial concentrations of sugar which was composed of inulin and fructose as weight ratio of one to one were 30, 50, 75, 100 and 150g/l and the initial densities of the microorganism were less than 0.5g/l, 10g/1 to 15g/1, and 50g/l. The functional relationship among specific growthrates, sugar concentrations, and alcohol concentrations could be expressed by Aiba-shoda equation and the specific growth rate represented the trend that decreased with increase in the initial concentration of the microorganism. Also, $\mu$max and Ks of Monod's equation could be expressed as the function of initial cell concentration like the following equations. $\mu$max=0.8-0.008X Ks=0.54X+8 In the region that sugar, alcohol and cell concentrations were 10g/1 to 120g/l, 0g/l to 60g/l and 0.5g/l to 50g/l respectively, the differences between the experimental values and the calculated ones for specific growth rate approached to 40% with respect to experimental values at the worst cases, but in most cases, those were distributed in the range of less than 20%.

• Journal of environmental and Sanitary engineering
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• v.13 no.1
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• pp.91-103
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• 1998

Design data for COD and nitrogen removal from wastewater were collected from Pilot's Multi-stage Bio-reactor. Hyraulic conditions and pollutant loadings were varied in order to optimize the biological and operational parameters. Pilot's experimental results summarize as followings. 1. T-N removal efficiency in the organic volumetric loading 0.2 kgCOD/m$^{3}$·d was obtained as maxium of 85% at internal recycle ratio 2.5 and in more ratio than this it was decreased. Organic removal efficiency was about 91% under the overall experimental conditions and not influenced by recycle ratio.. 2. Nitrification reaction was shown as maxium in the SCOD$_{cr}$/NH$^{+}$-N ratio of 6.5 and in more ratio than this it was decreased. Denitrification rate was the maxium as 85% in more than 7.5 of SCOD$_{cr}$/NO$_{x}$-N ratio and in the ratio over this ratio it becomes constant. 3. By utilizing an applied new model of Stover-Kincannon from Monod's kinetic model, concentration of T-N in the effluent according to flow quanity in the influent was estimated as 8.74 and -67.5 respectively. The formula for estimating T-N concentration of effluent was obtained like this: N$_e$=N$_0$(1- $\frac{8.74}{(QN$_0$/A)-67.05}$)

• KSBB Journal
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• v.18 no.6
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• pp.443-447
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• 2003

The microorganism was isolated from the night soil treatment plant for the removal of sulfur compounds. The growth conditions of the sulfur-oxidizing bacteria were investigated and the isolate characterized as Thiobacillus noveilus SRM. The optimal pH of Thiobacillus novellus SRM on cell growth was pH 7.0 and the optimal temperature was 30$^{\circ}C$ and the optimal air flow rate was 1 vvm, respectively. As a results of cell growth from the Monod plot, the specific growth rate was 0.032 hr$\^$-l/, $V_{max}$ was 1.43 hr$\^$-l/ and $K_{m}$ was 0.32, respectively. The thiosulfate oxidation by Thiobacillus novellus SRM was made of sulfate ion. The sulfate ion reduced pH and decreased cell growth.