• 한국물환경학회지
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• 제23권5호
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• pp.689-696
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• 2007

Kinetic analysis was important to develope the biological nutrient removal process effectively. In this research, anoxic-anaerobic-aerobic system was operated to investigate kinetic behavior on the nutrient removal reaction. Nitrification and denitrification were important microbiological reactions of nitrogen. The kinetics of organic removal and nitrification reaction have been investigated based on a Monod-type expression involving two growth limiting substrates : TKN for nitrification and COD for organic removal reaction. The kinetic constans and yield coefficients were evaluated for both these reactions. Experiments were conducted to determine the biological kinetic coefficients and the removal efficiencies of COD and TKN at five different MLSS concentrations of 5000, 4200, 3300, 2600, and 1900 mg/L for synthetic wastewater. Mathematical equations were presented to permit complete evaluation of the this system. Kinetic behaviors for the organic removal and nitrification reaction were examined by the determined kinetic coefficient and the assumed operation condition and the predicted model formulae using kinetic approach. The conclusions derived from this experimental research were as follows : 1. Biological kinetic coefficients were Y=0.563, $k_d=0.054(day^{-1})$, $K_S=49.16(mg/L)$, $k=2.045(day^{-1})$ for the removal of COD and $Y_N=0.024$, $k_{dN}=0.0063(day^{-1})$, $K_{SN}=3.21(mg/L)$, $k_N=31.4(day^{-1})$ for the removal of TKN respectively. 2. The predicted kinetic model formulae could determine the predicted concentration of the activated sludge and nitrifier, investigate the distribution rate of input carbon and nitrogen in relation to the solid retention time (SRT).

• 상하수도학회지
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• 제21권5호
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• pp.641-647
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• 2007

This study aims to find out optimum condition for hydrogen production and organic removal when treating food and swine wastewater together. For this purpose, various batch tests were conducted by changing mixture ratio from 6:4 (food wastewater:swine wastewater) to 1:9 without pretreatment process. For hydrogen production through anaerobic fermentation, the mixture ratios of R-1 (6:4), R-2 (5:5) and R-6 (1:9) were out of pH range appropriate for hydrogen production and mixture ratios of R-3 (4:6), R-4 (3:7), and R-5(2:8) showed appropriate hydrogen production where their pH ranges were 5.1~5.5. Especially in case of R-3, it consistently maintained appropriate pH range for hydrogen production for 72hr and produced maximum hydrogen. The characteristics of hydrogen production and cumulative hydrogen production according to each mixture ratio showed that R-1, R-2 and R-6 did not produce any hydrogen, and maximum hydrogen productions of R-3, R-4 and R-5 were 593ml, 419ml and 90ml, respectively. Total cumulative hydrogen productions of R-3, R-4 and R-5 were 1690ml, 425ml and 96ml, respectively. Based on previous results, it was concluded that, the most appropriate mixture ratio of food wastewater and swine wastewate rwas 4:6 (R-3). The experiment for COD removal rate to evaluate organic removal efficiency revealed that R-3, R-4 and R-5 showed high removal efficiencies during the highest hydrogen production amount and the highest efficiency was 41% with R-3.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.266-269
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• 2005

반응조의 유입수 CODcr농도를 $75000{\sim}95000mg/L$로 운전하였을 경우 유출수 CODcr농도는 $14000{\sim}19000mg/L$로서, 제거율은 $75{\sim}85%$로 나타났다. 고온소화$(45{\pm}2^{\circ}C)$로 운전한 결과 유입수 pH는 $4.2{\sim}4.5,$ 유출수의 pH는 $6.8{\sim}7.2$를 유지하였다. TS(총고형물질)와 VS(휘발성고형물질)의 유입수를 단계적으로 각각 $2.94{\sim}5.09%$와 $2.98{\sim}5.01%$로 유지할 경우, 유출수는 단계적으로 각각 $0.65{\sim}1.1%$와 $0.6{\sim}0.8%$였다. 유출수의 TS, VS의 제거율은 각각 78, 85%이었다. $CH_4$발생량은 0.28 $m^3-CH_4/kg-VS$이었다.

• 한국환경보건학회지
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• 제34권6호
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• pp.452-458
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• 2008

This study was undertaken to establish the biological reaction characteristics of the marine products industry wastewater which contains high concentrations of organic matter and saline. As the S/I is varied from 0.3 to 1.2, the results were follows : the observed ultimate anaerobic biodegradability varied from 72.0 to 88.0%, the first order reaction rate varied from 0.1735 to $0.3420\;day^{-1}$ and the second order reaction rate varied from 0.0132 to $0.0295\;day^{-1}$. When S/I was 0.9, the first order reaction rate had a maximum value, but the variations of the second order reaction rate were less than 1st-order reaction rate. When the operation time exceeded 2 days the gas production rapidly increased. The source of this rapid increase was due to that the activity of the granular sludge used in this study being faster than that of conventional sludge. Under aerobic condition, the characteristics of organic matter were as follows: the marine industry wastewater used in this study contained about 81% of biodegradable matter, and it was divided into readily biodegradable COD(Ss), slowly biodegradable COD(Xs), soluble COD(Si) and inert suspended COD (Xi). The percentages of each COD were 87.3%, 23.9%, 6.4% and 12.4% respectively.

• 공업화학
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• 제23권1호
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• pp.28-34
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• 2012

본 연구에서는 UASB 반응조를 이용하여 음폐수 탈리액을 원료로 하여 중온소화($35{\pm}0.5^{\circ}C$)와 고온소화($55{\pm}0.5^{\circ}C$)법을 통한 운전을 실시하였다. 20일 동안은 중온소화로 운전을 하면서 5일 간격으로 유출수 재순환 비를 단계적으로 변화시켰다. 고온소화 역시 중온소화와 마찬가지 조건으로 운전을 실시하였다. 실험결과 중온소화 시 유기물제거율은 90% 이상, 메탄수율은 약 66~70%로 나타났다. 고온소화 시 유기물제거율은 80% 이상, 메탄수율은 약 62~68%로 나타났다. 또한, 유출수 반송을 3Q 이상으로 반송하여 운전할 경우 경제적이며 안정적인 운전을 할 수 있었다.

• 한국미생물·생명공학회지
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• 제13권2호
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• pp.169-172
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• 1985

Rhodopseudomonas K-7은 혐기 광조건과 호기암조건에서 glucose, xylose로 이용하면서 성 장할 수 있었는데, 종배양시 glucose를 첨가하는 것이 본 배양에서 glucose자화를 촉진시켰고, glucose 60mM 배지에서 배양한 것을 종균으로 했을 때, glucose이 용량이 가장 많았다. Glucose 60mM배지에서 배양한 것을 종균으로 했을 때, 배지의 glucose 농도가 높더라도 이용할 수 있는 glucose양은 제한되어 있었다. 혐기 광조건에서 보다는 호기 암조건에서 성장속도도 빨랐고, glucose, xylose자화량도 많았다.

• 상하수도학회지
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• 제24권1호
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• pp.51-62
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• 2010

The high concentration of N in the wastewater from livestock farming generally renders the efficiency of the wastewater treatment. Therefore, removal of N in livestock wastewater is crucial for successful treatment. The current study was conducted to investigate the optimum conditions for partial nitrification under anaerobic condition following nitritation in TPAD-BNR(two-phase anaerobic digestion-biological nitrogen removal) operating system. Sequential operating test to stimulate partial nitrification in reactor showed that partial nitrification occurred at a ratio of 1.24 in $NO_2{^-}$-N:$NH_4{^+}$-N. With this result, a wide range of factors affecting stable nitritation were examined through regression analysis. In the livestock wastewater treatment procedure, the hydraulic retention time (HRT) and pH range for optimum nitrite accumulation in the reactor were 1-1.5 days and 7-8, respectively. It was appeared that accumulation of $NO_2{^-}$-N in the reactor is due to inhibition of the $NO_2{^-}$-N oxidizer by free ammonia (FA) while the effect of free nitrous acid was minimal. Nitrification was not influenced by DO concentration at a range of 2.0-3.0 mg/L and the difference in the growth rate between $NH_4{^+}$-N oxidizer and $NO_2{^-}$-N oxidizer was dependent on the temperature in the reactor.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.478-481
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• 2006

Energy is vital to global prosperity, yet dependence on fossil fuels as our primary energy source contributes to global climate change environmental degradation, and health problems. Hydrogen $(H_2)$ offers tremendous potential as a clean renewable energy currency. Hydrogen has the highest gravimetric energy density of any known fuel and is compatible with electrochemical and combustion processes for energy conversion without producing carbon-based emission that contribute to environmental pollution and climate change. Numerous methodologies have been developed for effective hydrogen production. Among them, the biological hydrogen production has gained attention, because hydrogen can be produced by cellular metabolismunder the presence of water and sunlight. The green alga Chlamydomonas reinhardtii is capable of sustained $H_2$ photoproduction when grown under sulfur deprived condition. Under sulfur deprived conditions, PSII and photosynthetic $O_2$ evolution are inactivated, resulting in shift from aerobic to anaerobic condition in the culture. After anaerobiosis, sulfur deprived algal cells induce a reversible hydrogenase and start to evolve $H_2$ gas in the light. According to above principle, we investigated the effect of induction parameters such as cell age, cell density. light intensity, and sulfate concentration under sulfur deprived condition We also developed continuous hydrogen production system by sulfate re-addition under sulfur deprived condition.

• 한국미생물·생명공학회지
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• 제26권1호
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• pp.7-14
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• 1998

Bifidobacterium spp.의 내 산소성기작을 밝히기 위하여, 산소에 민감한 B. adolescentis와 상대적으로 산소에 내성이 있는 B. longum을 선정하여 혐기적 조건, 미호기성 조건,호기성 배양 조건 등에서 그 생육,산화 효소들의 활성, 세포 지방산 조성의 변화 등을 연구하였다. B. adolescentis의 생육은 미 호기성 조건에서 민감하게 저해되었으나, B. longum은 같은 조건에서 혐기배양과 같은 정도의 생육을 유지하였다. 이들 조건에서 두 균주의 catalase는 관찰되지 않은 반면, superoxide dismutase는 B. adolescentis와 B. longum모두에서 관찰되었으며 어느 조건에서든 B. adolescentis은 B. longum보다 높은 활성을 나타내었다. NADH oxidase와 NADH peroxidase의 활성은 B. adolescentis에서는 매우 낮은 반면, B. longum에서는 일정한 수준의 활성을 보였으며, 이 활성은 혐기적 배양조건에서 보다는 미호기성 조건에서 3.7-11.4배 증가하였다. 세포의 지방산 분석 결과 두 균주 모두 $C_{l6:0}$과 $C_{l8:1}$이 전체 methylated성분 중 60-70%를 차지했다. B. longum에는 특히 $C_{l9:0 cyclo 9,10}$가 2-14% 함유되어 있었으며, 이는 lactobacillic acid와는 cylization 위치가 다른 cis 9, 10-methylene octadecanoic acid이었고 미호기적 배양과 정지기 세포에서 증가되는 경향을 보였다. 두 균주 모두 혐기균에서만 확인된 세포막의 plasmalogen의 존재로 인한 dimethyl acetals(DMA)을 함유하고 있었는데 이 중 $C_{l8:1}$ DMA는 호기성 조건에서 현저히 감소되었다. 산소 stress환경의 bifidobacteria의 생육에 있어 NADH oxidative enzymes은 중요한 역할을 하며, 이들 효소체계와는 별도로 환경에 적응하기 위한 세포구조적 변화의 일부로 지방산 $C_{l9:0}$ Cyclo와 plasmalogen의 $C_{l8:1}$ 등이 변화한 것으로 생각된다.

• KSBB Journal
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• 제7권2호
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• pp.126-131
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• 1992

P. shermanii IFO 1239을 이용 vitamin $B_{12}$를 생산할 때 산소의 영향은 매우 큼 것으로 나타났는데 배양 전반부는 혐기적 조건이, 후반부는 호기적 조건이 vitamin $B_{12}$ 생성증진에 효과적임이 밝혀졌다. 본 연구를 통하여 배양 48시간 동안은 복합배지상에서 혐기적으로 배양하다가 48시간 이후부터는 합성배지로 바꾸고 호기적 조건으로 배양해주는 방법이 vitamin $B_{12}$ 의 생성을 증가시켰다. 이런 배양방법을 이용하여 탄소원과 유기산이 vitamin $B_{12}$ 생성에 미치는 영향을 알아본 결과 glucose, fructose, lactose가 좋은 탄소원이었으며 유기산 중에서는 succinate 와 malate가 각각 34.9%와 18.7%의 vitamin $B_{12}$생성을 촉진시켰다.