• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.737-743
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• 1999

A conventional thermophilic anaerobic digester was converted into a thermophilic high-rate hybrid anaerobic reactor (THAR) for treating distillery wastewater. The THAR has been operating successfully since May 1995 at a loading rate of 5.45 to $11.52{\;}kg/\textrm{m}^3/d$ (maximum of 15.02). The THAR has demonstrated a soluble Chemical Oxygen Demand (sCOD) removal efficiency of 85 to 91% and a total COD (tCOD) removal efficiency of as much as 72 to 84%. Product gas had a methane content of 59 to 68%. The tCOD removal rates were 4.31 to 5.43, 6.26 to 6.89, and 9.03 to $9.78kg{\;}tCOD/\textrm{m}^3/d$ for tapioca, com, and naked-barley wastewater, respectively. The sCOD removal rates ranged from 3.75 to 4.79,3.28 to 4.89, and 5.57 to 6.21kg $sCOD/\textrm{m}^3/d$ for tapioca, com, and naked-barley wastewater, respectively. There were unknown substances in a naked-barley distillery wastewater that were identified as being toxic for microorganisms. However, the THAR treated naked-barley wastewater continuously for 26 days, operating at an average tCOD loading of $11.08{\;}kg/\textrm{m}^3/d$without any signs of deterioration in either COD removal efficiency or gas production rate. During this period, the average removal efficiencies of tCOD and sCOD were 84% and 91%, respectively, and the gas production rate averaged 6.61 to $7.57{\;}\textrm{m}^3/\textrm{m}^3$ reactor/d which produced 0.57 to $0.69{\;}\textrm{m}^3{\;}biogas/kg{\;}tCOD_{rem}$. From tapioca and com wastewater, the reactor showed an average gas production rate of 3.18 to 3.46 and 4.91 to $5.22{\;}\textrm{m}^3/\textrm{m}^3$ reactor/d which produced 0.53 to 0.69 and 0.62 to $0.71{\;}\textrm{m}^3/kg{\;}tCOD_{rem}$, respectively.

• 대한환경공학회지
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• 제31권12호
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• pp.1135-1142
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• 2009

본 연구는 고분자 응집제를 이용하여 짧은 시간에 입상형태의 슬러지를 제조한 다음, 입상슬러지를 호기성 입상화 장치에 주입하여 입상화를 시도하였다. 각 반응조에서 호기성 입자의 형성에 따른 입자의 크기, 밀도, 입자내 미생물 체외분비 고분자물질 등의 물리.화학적인 특성을 조사하였다. 입상형태의 슬러지를 호기성 입상화 장치에 주입하여 COD 부하량 3, 6, 9 $kg{\cdot}COD/m^3{\cdot}d$로 35일간 운전한 결과 최종 형성된 호기성 입장의 평균 크기는 각각 3.6 mm, 4.3 mm, 3.4 mm 이었고 호기성 입자의 침강속도는 각각 1.5 cm/s, 1.6 cm/s, 1.2 cm/s 이었다. COD 부하량에 따른 미생물 군집체의 비성장속도는 0.12 $d^{-1}$, 0.135 $d^{-1}$, 0.133 $d^{-1}$이었으며 전반적으로 호기성 입상화 장치에서는 COD 부하량이 $6kg{\cdot}COD/m^3{\cdot}d$로 운전된 반응조에서 호기성 입자의 물리 화학적인 특성이 우수하였다.

• Fisheries and Aquatic Sciences
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• 제16권3호
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• pp.211-220
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• 2013

A shaking motion could be used to improve fish escapement from a cod-end net by creating a sieving effect over the swept volume or by disturbing the optomotor response of the fish. In this study, a perpendicular shaking motion was generated in a towed cod-end net by a circular canvas attached to the end of the codend, which formed a biased cap-like shape. This concept was tested by using a model in a flow tank and by towing a prototype cod-end during sea trials. For the model tests, the amplitude of the shaking motion was $0.6{\pm}0.1$ times the rear diameter of the cod-end, and the period of the shaking motion was $2.6{\pm}0.1$ s at a flow velocity of 0.6 or 0.8 m/s. In the sea trials, the amplitude was $0.5{\pm}0.2$ times the rear diameter of the cod-end, and the period of the shaking motion was $7{\pm}4$ s at towing speeds of 1.2 or 1.7 m/s. Thus, the shaking amplitude during the sea trials was equal to or less than that observed in the tank tests, and the shaking period was twice as long. The shaking motion described by the amplitude and period could be an effective means to stimulate fish escapement from cod-end during fishing operations considering the response of the fish.

• 한국정보통신학회논문지
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• 제11권7호
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• pp.1260-1266
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• 2007

정보통신기술이 발전하면서 방송 통신 융합(Convergence)의 시대가 되었다. 방송 통신 융합의 대표적인 서비스로 iCOD(internet Contents On Demand)가 있다. 이는 초고속 인터넷을 이용하여 정보 서비스, 동영상 콘텐츠 및 방송 등을 텔레비전 수상기로 제공하는 서비스이다. 그러나 이 서비스는 다른 채널의 방송 정보를 검색 하려면 다른 방송의 스트림을 다시 분석해야 한다는 문제점이 있다. 이에 본 논문에서는 iCOD 방송 서비스를 단말에서 효율적으로 검색하고 선택하는 것을 지원하기 위하여 iCOD 용 방송 스트림으로부터 SI(Service Information) 정보를 추출하여 SD&S(Service Discovery and Selection) 기반 iPG(internet Program Guide) XML문서를 생성하고 멀티 캐스트로 전송하는 시스템을 설계 및 구현하였다.

• Membrane and Water Treatment
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• 제1권4호
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• pp.273-282
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• 2010

Treatment and reuse of industrial wastewater is becoming a major goal due to water scarcity. This may be carried out using membrane separation technology in general and reverse osmosis (RO) in particular. In the current study, polyamide (FT-30) membrane was employed for treatment of wastewater obtained from Faraman industrial zone based in Kermanshah (Iran). The effects of operating conditions such as transmembrane pressure, cross flow velocity, temperature and time on water flux and rejection of impurities including COD by the membrane were elucidated. The aim was an improvement in membrane performance. The results indicate that most of the chemical substances are removed from the wastewater. In particular COD removal was increased from 64 to around 100% as temperature increased from 15 to $45^{\circ}C$. The complete COD removal was obtained at transmembrane pressure of 20 bars and cross flow velocity of 1.5 m/s. The treated wastewater may be reused for various applications including makeup water for cooling towers.

• Bulletin of the Korean Chemical Society
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• 제25권7호
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• pp.1012-1019
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• 2004

The synthesis of novel group 9 metal complexes containing the S,S'-chelate ligands, $Li_2S_2C_2B_{10}H_{10}$ (2a) and $LiS(S=PMe_2)C_2B_{10}H_{10$} (2b), is described. Two new dinuclear complexes of the type $[{(cod)M}_2(S,S'-S_2C_2B_{10}H_{10})]$ (cod = 1,5-cyclooctadiene; M = Rh (3a), or Ir (3b)) were synthesized by the reaction of chloridebridged dimers $[M({\mu}-Cl)(cod)]_2$ with one molar equivalent of the corresponding dilithium dithiolato ligand $Li_2S_2C_2B_{10}H_{10}$ (2a). X-ray crystal structure analysis of 3a revealed a dinuclear structure in which each (cod)Rh unit is attached to a distinct sulfur atom of a 1,2-dithio-o-carboranyl ligand (2a). Additionally, the electrochemical properties of 3a and 3b were investigated by cyclic voltammetry. In an analogous manner, reaction of the lithium dithiolato ligand $LiS(S=PMe_2)C_2B_{10}H_{10}$ (2b) with $Cp^{\ast}CoI_2(CO)$ produced a mononuclear dithiolato complex, $[Cp^{\ast}CoI{(S,S'-S(S=PMe_2)C_2B_{10}H_{10})}]$ (4), which was characterized by single-crystal X-ray analysis.

• KSBB Journal
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• 제14권1호
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• pp.119-123
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• 1999

Polyester 감량폐수의 주성분 중 물리.화학적 처리가 어려운 EG를 생물학적으로 처리하기 위하여 jet-loop reactor를 사용하였다 Jet-loop reactor의 산소전달계수는 air-lift reactor와 비교하여 훨씬 컸다. 합성 polyester 감량폐수를 사용하여 부하율 2.64 $kgCOD_{Mn}/m^3$.day, 3.07$kgCOD_{Cr}/m^3$.day로 처리한 경우 유출수의 농도는 154 $mgCOD_{Mn}/L$, 156$mgCOD_{Mn}/L$이었으며, 이 때 각각 93, 93.9%의 제거율을 나타내었다. $COD_{Mn}$의 비부하 속도가 0.25에서 1.72$kgCOD_{Mn}/kgMLVSS$.day로 증가 함에 따라 비기질제거 속도는 0.25에서 1.60$kgCOD_{Mn}-removed/kgMLVSS$.day로 선형적으로 증가하였다. 그리고, 동력학적 계수 Y는 0.78,$K_d$는 0.1$day^{-1}$, $K_s$는 89mg/L는 k는 0.05$hr^{-1}$이었다. 실제 polyester 감량폐수를 사용하여 부하율 2.64$kgCOD_{Mn}/m^3$.day,5.24$kgCOD_{Cr}/m^3$.day로 처리한 경우 유출수의 농도는 150$kgCOD_{Mn}/L$, 3.6$kgCOD_{Cr}/L$이었으며, 이때 각각 93.2,93%의 제거울을 나타내었다.

• 한국미생물·생명공학회지
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• 제36권3호
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• pp.233-239
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• 2008

A new approach to the solubilization of excess activated sludge by the inoculation of lactic acid bacteria was studied to reduce the amount of sludge produced in the activated sludge treatment process. Aerobic microorganism in sludge was lysed in anaerobic condition and the cytoplasmic substance eluted was utilized as a carbon source by lactic acid bacteria. On the basis of sludge solubilization efficiency, Lactobacillus brevis and Leuconostoc mesenteroides subsp mesenteroides were selected the best candidates among five kinds of Lactobacillus sp. and seven kinds of Leuconostoc sp. The sludge solubilization efficiency by heterofermentative lactic acid bacteria was more efficient than that of homofermentative bacteria. Initial value of soluble COD (sCOD) was 1050 mg/L at the initial inoculation time increased to 3070 mg/L (192% solubilization) at 96 h of the incubation time. The inoculation of lactobacillus brevis to the sludge resulted in 2824% increase in sCOD value after 96 h of incubation than the control experiment. Leuconostoc mesenteroides subsp mesenteroides showed 152% increase of solubilization and 30% increase of S-COD/T-COD on 96 h of incubation time. Considering the increase of S-COD by the inoculation of Leuconostoc sp. on 24 h, 10% inoculation of lactic acid bacteria to the sludge was most effective.

• 한국환경보건학회지
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• 제31권4호
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• pp.246-253
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• 2005

The supernatant treatment of recovery process of raw materials of paper plant was studied using DAF (Dissolved Air Flotation) system. We investigated the removal efficiency (COD, SS and turbidity) of the DAF process. The effects of parameters such as A/S ratio, pressure, flotation conditions, coagulant concentration, mixing conditions, size and ratio of packing and nozzle type were examined. The results showed that the optimum A/S ratio and pressure were 0.058 and 4.5-5 atm, respectively. Injection times of pressurized water around 30 s and flotation times around 10 min appeared to be optimal for the DAF operation. Anion polymer addition improved the removal of COD, SS and turbidity. The smaller size and the more packing ratio were enhanced the removal efficiencies. The order of performance of nozzle was full cone > flat > assemble type.

• 유기물자원화
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• 제17권1호
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• pp.58-72
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• 2009

본 연구에서는 하수 내에 존재하는 유기물과 미생물량 분액을 위해 미생물 호흡률 측정기(Respirometer)를 구동하여 미생물에 의한 산소 섭취율(OUR : Oxygen Uptake Rate)을 측정하고, CG-FID 혹은 LC를 활용하여 VFAs(Volatile Fatty Acids)를 측정하였다. 유기물은 IAWQ (International Association of Water Quality)의 ASM(Activated Sludge Model)에서 명시된 유기물 분류법에 따라 분액 하였으며, ASM 중에서도 ASM No.2d를 기초하여 분액을 수행하였다. 하지만 슬러지를 첨가하지 않은 하수 원액의 미생물 호흡률 측정과 더불어 기존의 방법과는 다르게 여과한 하수의 미생물 호흡률 측정과 VFAs 측정을 수행하여 하수에 포함된 유기물량을 추정하였다. 이는 기존의 하수 원액을 이용한 미생물 호흡률 측정 방법에 있어 천천히 생분해되는 용존성 유기물질(S_S)에 의한 산소섭취율과 천천히 생분해되는 입자성 유기물질(X_S)에 의한 산소섭취율이 동일 그래프 안에 형성되어 정확하게 구분되지 못하는 단점과 슬러지 세척으로 인한 실험의 오차를 보완하고자 하였다. 또한 용존성 난분해 COD(S_I)을 측정하는 기준이 명확하지 않는 문제점이 발생하여 미생물 호흡률 측정 과정에서 그래프의 변화를 보고 정확한 용존성 난분해 COD(S_I)의 측정 시간을 선택할 수 있는 방법을 제시하였다. 여과한 하수를 대상으로 미생물 호흡률 측정과 VFAs 측정을 통하여 추정한 유기물 분액 결과 용존성 난분해 COD인 S_I는 $12.2g/m^3$로 Total $COD_{Cr}$ 기준으로 6.9%, 발효 부산물인 S_A는 $24.76g/m^3$로 Total $COD_{Cr}$ 기준으로 14.1%, 발효 가능한 유기물질인 S_F는 $58.54g/m^3$로 Total $COD_{Cr}$ 기준으로 33.2%, 천천히 생분해되는 입자성 유기물질인 X_S는 $61.1g/m^3$로 Total $COD_{Cr}$ 기준으로 34.7%, 입자성 난분해 COD인 X_I는 $10.2g/m^3$로 Total $COD_{Cr}$ 기준으로 5.8%로 추정되었다. 종속영양 미생물량인 X_H는 $9.3g/m^3$로 Total $COD_{Cr}$ 기준으로 5.3%로 추정되었다.