• KSBB Journal
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• v.19 no.2
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• pp.143-147
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• 2004

Biodegradation of dimethyl sulfide (DMS) was studied in a batch culture using Gordonia sihwaniensis PKL-1 isolated from a compost biofilter after 100 days of operation for the removal of volatile organic compounds. Optimal pH and temperature for the removal of DMS were 7 and $25^{\circ}C$, respectively. The Michaelis-Menten kinetic constants for DMS removal, $\upsilon_{max}$ and $K_s$, were 0.0016 mg/(mg-protein)ㆍhr, and 8.05 mg/L, respectively.

• KSBB Journal
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• v.18 no.6
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• pp.529-535
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• 2003

We studied degradation effects of hydrophobic substrate such as kerosene and diesel by adding a biosurfactant originated from Pseudomonas aeruginosa F722 and chemical surfactants (Tween 80 and detergent) with aeration. The surface tensions of the biosurfactant, Tween 80 and detergent were 30mN/m, 39mN/m and 31mN/m, respectively. When the concentration of biosurfactant added in C-medium was 0.01 and 0.15%(w/v), the ratios of hydrocarbon degradation were 94.3％ and 94.2% respectively. It was 6.2%(w/v) higher than when the concentrations of added biosurfactant were 0.05, 0.1 and 0.2％. The degradation ratios of the chemical surfactants (Tween 80 and detergent) were 94.5％ and 93.5％ respectively. The effects of the biosurfactant and chemical surfactants were similar on the degradation ratio in mixtures of kerosene and diesel. However, the population of viable p. aeruginosa F722 at the end of the cultivation period was twice as higher in the biosurfactant than that in the chemical surfactant. We also studied the effect of aeration (0.5vvm) on the degradation ratio. The biosurfactant addition experiment was conducted with 0.5vvm air, 35$^{\circ}C$, 150rpm, pH 8.0, 3days, 1.0% (w/v) substrate. When p. aeruginosa F722 and 0.15%(w/v) biosurfactant were added, the degradation ratio of hydrocarbon was 94.8％. Without p. aeruginosa F722, it was 68%. Thus, with aeration, the degradation ratio of hydrocarbon was increased by 26.8％. In addition, the cultivation time was shortened by 1/3. The degradation ratios of hydrocarbon in shaking culture (cultivation time; 3days) and stationary culture (cultivation time; 10days) were 94.8 and 93.7％ respectively. Thus, the addition of biosurfactant and aeration enhanced the degradation of hydrocarbon originated kerosene and diesel.

• Microbiology and Biotechnology Letters
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• v.12 no.4
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• pp.305-309
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• 1984

A selective medium which allows growth of only cellulolytic bacteria was developed. The medium composed of 0.5% carboxymethylcellulose (CMC), 0.005% yeast extract, minerals and agar. Colony formation on this medium indicates overall activities of cellulose utilization. A subsequent test with Congo Red dye could distinguish extracellular cellulolysis from intracellular type.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.3
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• pp.195-203
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• 2012

In this study, The effects of three different biological activated carbon (BAC) materials (each coal, coconut and wood based activated carbons) and anthracite, empty bed contact time (EBCT) and water temperature on the removal of MK, HHCB and AHTN in BAC filters were investigated. Experiments were conducted at three water temperatures (5, 15 and $25^{\circ}C$) and four EBCTs (5, 10, 15 and 20 min). The results indicated that coal based BAC retained more attached bacterial biomass on the surface of the activated carbon than the other BAC, increasing EBCT or increasing water temperature increased the synthetic musk compounds (SMCs) removal in BAC columns. The kinetic analysis suggested a first-order reaction model for MK, HHCB and AHTN removal at various water temperatures (5, 15 and $25^{\circ}C$). The pseudo-first-order biodegradation rate constants and half-lives were also calculated for MK, HHCB and AHTN removal at 5, 15 and $25^{\circ}C$. The pseudo-first-order biodegradation rate constants and half-lives of MK, HHCB and AHTN ranging from 0.0082 $min^{-1}$ to 0.4452 $min^{-1}$ and from 1.56 min to 84.51 min could be used to assist water utilities in designing and operating BAC filters for SMCs removal.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.2
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• pp.96-101
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• 2009

In this study, the effects of three different biological activated carbon (BAC) materials (each coal, coconut and wood based activated carbons), empty bed contact time (EBCT) and water temperature on the removal of sulfonamide 5 species in BAC filters were investigated. Experiments were conducted at three water temperatures (5, 15 and $25^{\circ}C$) and four EBCTs (5, 10, 15 and 20 min). The results indicated that coal based BAC retained more attached bacterial biomass on the surface of the activated carbon than the other BACs, increasing EBCT or increasing water temperature increased the sulfonamide 5 species removal in BAC columns. In the coal-based BAC columns, sulfachloropyridazine (SCP), sulfamethazine (SMT) and sulfathiazole (STZ) removal efficiencies were 30~80% and sulfadimethoxine (SDM), sulfamethoxazole (SMX) removal efficiencies were 18~70% for 5~20 min EBCT at $25^{\circ}C$. The kinetic analysis suggested a first-order reaction model for sulfonamide 5 species removal at various water temperatures (5~$25^{\circ}C$). The pseudo-first-order reaction rate constants and half-lives were also calculated for sulfonamide 5 species removal at 5~$25^{\circ}C$. The reaction rate and half-lives of sulfonamide 5 species ranging from 0.0094~0.0718 $min^{-1}$ and 9.7 to 73.7 min various water temperaturs and EBCTs in this study could be used to assist water utilities in designing and operating BAC filters for sulfonamide antibiotic compounds removal.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.64-71
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• 2018

The purpose of this study is to investigate the characteristics of the substrate of dairy wastewater through aerobic biodegradation and to use the results as the basic data for the efficient treatment of dairy wastewater. The SCODcr of the part of the matter that consisted of readily biodegradable organics (Ss) was 84.2%, which is higher than those of seafood processing wastewater (75.8~77.9%) and pigpen wastewater (58.2%). The proportion of non-biodegradable organics (SI) ranged from 5.6% to 6.4%, and the proportion of inert organics (SIi) generated by microbial metabolism ranged from 3.6 to 3.7%. The content coefficient (YI) of the non-biodegradable dissolved organic matter was in the range of 0.092 to 0.099, and the generation coefficient (Yp) of the inert substance produced by the microbial metabolism was in the range of 0.039 to 0.040. The analysis results of the organic component coefficient showed that approximately 91.0% of the dissolved organic matter of the dairy wastewater was biodegradable, and approximately 92.5% of the dissolved organic matter was the Ss component. Furthermore, the proportion of biodegradable organic matter in the total organic matter (TCODcr) was 89.3%. The proportions of non-biodegradable organics (SI) and non-biodegradable suspended organics (XI) were 3.0% and 7.7%, respectively, which are lower than those in similar wastewater. This means that the milk processing wastewater has a high aerobic biodegradability.

• Journal of Environmental Health Sciences
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• v.22 no.3
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• pp.1-7
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• 1996

Polychlorinated Biphenyls(PCBs)의 생물학적 처리가 시도되고 있으며, PCBs를 분해할 수 있는 미생물을 이용할 수 있다. 따라서 본 연구에서는 폐기된 절연유의 생물학적 처리를 위하여 PCBs를 분해하는 균을 분해하였으며, 분해된 균을 이용하여 절연유 내의 Polychlorinated Biphenyls(PCBs) 분해를 회분식 실험에서 연구하였다. 대구의 신천으로부터 유일한 탄소원으로 Biphenyl을 포함하고 있는 고체배지에서 PCBs를 분해할 수 있는 Pseudomonas sp. P2 균주를 분해하였다. PCBs의 용해도를 높이기 위해 사용된 유화제 alkyl aryl ethoxylated phosphate가 200 mg/L에서는 Pseudomonas sp. P2 균주의 성장에 영향을 미치지 않았다. 1000 mg/L의 Biphenyl과 PCBs에 Pseudomonas sp. P2를 접종하여 160시간 배양후에 Biphenyl과 PCBs의 분해가 각각 97.5%, 58.0%였다. Biphenyl 1000 mg/L에서 최대성장율($\mu_{max}$)은 0.34 $day^{-1}$, 0.26 였다. 따라서 염소가 결합되지 않은 Biphenyl는 염소가 결합된 PCBs보다 분해가 빠르게 진행되었다. 또한 Pseudomonas sp. P2는 Biphenyl과 PCBs의 분해로 부터 유도된 황색의 분해대사산물을 확인하였다. 본 연구에서는 Pseudomonas sp. P2 균주가 절연유 내의 PCBs를 분해할 수 있다는 것을 확인하였다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.373-374
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• 2005

1. 조사량의 증가는 PVA의 분해를 향상시켰다. 2. PVA의 초기 농도가 50 mg/L일 경우 1 kGy에서 99% 이상의 분해효과를 나타내었으며, 250 mgh일 경우 39.2% 의 분해 효과를 나타내어, PVA의 방사선에 의한 분해는 PVA초기농도에 영향을 받고 있음을 알 수 있다. 2. PVA 자체는 방사선에 의해서 효과적으로 분해 되었지만, TOC의 경우 초기농도50mg/L의 PVA를 제외하고는 아주 미비한 제거 효과를 보였다. 하지만 생분해도가 증가함으로써 방사선 처리후 생물학적 처리의 연계는 PVA를 완전히 산화시키기 위한 효과적인 방안이 될 수 있을 것임을 예측할 수 있었다.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.12
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• pp.1255-1261
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• 2008

In this study, The effects of three different biological activated carbon (BAC) materials (each coal, coconut and wood based activated carbons), empty bed contact time (EBCT) and water temperature on the removal of haloacetic acid (HAA) 5 species in BAC filters were investigated. Experiments were conducted at three water temperatures (5, 10 and 20$^{\circ}C$) and four EBCTs (5, 10, 15 and 20 min). The results indicated that coal based BAC retained more attached bacterial biomass on the surface of the activated carbon than the other BAC, increasing EBCT or increasing water temperature increased the HAA 5 species removal in BAC columns. To achieve an HAA removal efficiency 50% or higher in a BAC filter, the authors suggest 10 min EBCT or longer for 5$^{\circ}C$ waters and 5 min EBCT for waters at 10$^{\circ}C$ or higher. The kinetic analysis suggested a first-order reaction model for HAA 5 species removal at various water temperatures (5, 10 and 20$^{\circ}C$). The pseudo-first-order reaction rate constants and half-lives were also calculated for HAA removal at 5, 10 and 20$^{\circ}C$. The pseudo-first-order reaction rate constants and half-lives were also calculated for HAA 5 species removal at 5$\sim$ 20$^{\circ}C$. The half-lives of HAA 5 species ranging from 0.75 to 18.58 min could be used to assist water utilities in designing and operating BAC filters for HAA removal.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.283-283
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• 2015

1,4-dioxane은 페인트, 광택제 및 코팅제의 제조시에 첨가되는 화학물질로 인간에 대한 발암 가능성과 수중에서의 지속성으로 인해 EPA priority pollutant로 지정되어 있다. 이에 최근 고도산화법을 이용한 처리가 계속적으로 연구되고 있으며, UV/$H_2O_2$ 공법을 통하여 수계에서 발견되는 난분해성 유기 오염물의 제거가 효과적인 것으로 밝혀졌다. 하지만 고도산화공정(AOP)은 다량의 에너지 소모와 산화제 투여로 인한 높은 운전비용이 현실적인 적용에 장애가 되고 있다. 한편 상대적으로 저렴한 비용으로 1,4-dioxane을 처리할 수 있다는 장점으로 인하여 생물학적 분해에 대한 많은 연구가 진행되어 왔다. 하지만, 1,4-dioxane에 대한 많은 연구들이 주로 분해미생물의 분리동정 및 회분식 분해특성에 대한 연구들 위주로 보다 실질적인 연속적 처리반응조의 운전결과들은 거의보고 되지 않고 있다. 본 연구는 Lab scale 연속처리반응조의 장기운전 후 pilot plant 현장적용에 앞서 인공폐수와 합성폐수에서의 분해효율 비교 회분식 실험을 통해 합성폐수내 생물학적 분해에 영향을 미치는 inhibitor의 영향을 확인하였으며, 미생물의 배양 조건에 따른 분해효율 비교 회분식 실험과 modeling을 통하여 현장운영 효율을 예측하였다. 이를 반영하여 추후 진행예정인 pilot plant의 현장 적용성 검토 및 최적 설계인자 도출, 장기운전에서의 효율성 증대를 목적으로 한다.