• 청정기술
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• 제6권1호
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• pp.39-49
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• 2000

초고속응집침전공정(URC)은 가중응집제(WCA) 첨가와 슬러지 반송을 통해 floc의 침전 속도를 향상시키고, 입자표면의 흡착을 활성화하여 오염물을 보다 효율적으로 제거할 수 있으며, lamella plate를 포함하는 침전조를 이용하여 초기 우수 유출(CSO)과 같은 막대한 유량에 대하여 경제성 있는 침전조 수면적 부하를 획득할 수 있음을 확인하였다. 또한, 침전조의 최적설계를 위해 유체 유동장 모델을 이용한 모사가 수행되었으며, 공정에서 발생되는 슬러지에 대한 재활용 가능성을 평가하여 2차적 오염부하를 억제하기 위한 방안을 모색하였다.

• Journal of Yeungnam Medical Science
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• 제6권2호
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• pp.247-255
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• 1989

피부 농양절개술 후 계속되는 출혈을 주소로 입원한 진성다혈증 환자에서 혈액응고인자, I, VIII, IX, XI등의 감소와 혈소판의 기능 장애를 동반한 1례를 경험하였기에 문헌고찰과 함께 보고하는 바이다.

• 한국물환경학회지
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• 제28권5호
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• pp.729-742
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• 2012

Recently, to using chemical coagulation process for T-P removal in STP effluent as tertiary treatment process is generalized in the country. The importance of analysis technique to save the treatment & maintenance cost during coagulation process is becoming more increased each day. Thus, it is necessary for the analysis technique during coagulation process to be presented well the characteristic of coagulation in field apply. There are a few analysis techniques such as Jar Test, zeta potential analysis and streaming current detecting techniques. But there are difficult to apply in field immediately due to long test time and difficult analysis techniques. And using PDA technique, it is reviewed applicability of the techniques as field index on pilot plant of P-CAP system The P-CAP system is composed of an in-line static mixer, a Flocculation Tank and the CAP reactor with 2 stage weir for effluent. Pre-test is performed to fix the mixing velocity in the Flocculation Tank using the PDA equipment and it fixed with 30RPM. Also, Jar Test is performed to select optimum dose of each coagulant for each T-P concentration level of influent. Result of continuous test on pilot plant of P-CAP system, the FSI in the Flocculation Tank is increased consistently by increasing each dosing concentration of coagulant such as LAS and PAC in the low level influent T-P concentration comparatively. It is considered that formed Al-hydroxide complexes for dosed coagulant are caused FSI variation. Furthermore, it seems that FSI value in the high level influent T-P concentration appeared lower than the opposite influent condition relatively because it is formed simultaneously Al-hydroxide complexes as solid type and Al-phosphorus complexes as soluble type. Thus, relation of FSI by PDA technique and T-P removal of final effluent on pilot plant of P-CAP system are very limited for the kind of coagulant and the characteristics of influent. And it though that FSI value by PDA technique with analyzing of turbidity in Flocculation Tank will be used restrictedly on field as the relative field-index.

• 환경위생공학
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• 제15권4호
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• pp.27-27
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• 2000

In order to treat the dyeing wastewater, the UV/TiO₂/H₂O₂ system was investigated, and proper pretreatment methods were examined to reduce the load on the system considering economical and technical efficiency. The results of this study were as follows: 1.UV/TiO₂/H₂O₂ system with pretreatment process was adopted, the result of Chemical coagulation and pH control units was pH 11→ coagulation → pH 4 and the optimum dosage of FeCl₃ was 600㎎/ℓ 2. Proper dosage of TiO₂in the UV/TiO₂/H₂O₂ system with pretreatment process was 2g/ℓ and H₂O₂ was 1000㎎/ℓ, UV contact time was 20min to get below 200㎎/ℓ of $COD_{Cr}$

• 환경위생공학
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• 제15권4호
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• pp.26-34
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• 2000

In order to treat the dyeing wastewater, the $UV/TiO_2/H_2O_2$ system was investigated, and proper pretreatment methods were examined to reduce the load on the system considering economical and technical efficiency. The results of this study were as follows: 1. $UV/TiO_2/H_2O_2$ system with pretreatment process was adopted, the result of Chemical coagulation and pH control units was $pH{\;}11{\;}{\rightarrow}{\;}coagulation{\;}{\rightarrow}{\;}pH{\;}4$ and the optimum dosage of $FeCl_3$ was $600mg/{\ell}$. 2. Proper dosage of $TiO_2$ in the $UV/TiO_2/H_2O_2$ system with pretreatment process was $2g/{\ell}$ and $H_2O_2$ was $1000mg/{\ell}$, UV contact time was 20min to get $200mg/{\ell}$ of $COD_{Cr}$.

• 한국환경과학회지
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• 제32권10호
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• pp.731-739
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• 2023

In this study, lab-scale phosphorus coagulation/precipitation experiments were performed using three types of polyaluminum chloride (PAC) with different Al contents (10%, 12%, and 17%). The PO₄-P removal efficiencies at various operating conditions, such as initial PO₄-P concentration, initial pH, and Al/P molar ratio, were evaluated, and correlations among the operating factors affecting phosphorus coagulation/precipitation with PAC were derived to optimize the process efficiency. When the initial PO₄-P concentration was 0.065 and 0.161 mmol P/L under an initial pH of 8-10, the optimal PAC dose was 0.126-0.378 and 0.189-0.667 mmol Al/L, respectively. Under these conditions, the Al/P molar ratio was 2.16-6.18 and 1.28-4.30, respectively, and the PO₄-P removal efficiency was in the range of 40.2-92.5%. When the Al/P molar ratio was 2 or less under an initial pH condition of 6-8, the PO₄-P removal efficiency was approximately ≤40% owing to insufficient Al³⁺ ions. However, when the Al/P molar ratio is 3-5, the PO₄-P removal efficiency improved to approximately 80-90%. Thus, the optimal Al/P molar ratio to achieve a PO₄-P removal efficiency of over 90% was determined to be approximately 4 in the PO₄-P coagulation/precipitation process using PAC.

• 한국물환경학회지
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• 제25권2호
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• pp.227-234
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• 2009

In this research, a retrofitting process, which consists of a pretreatment system (coagulation) for dye wastewater combined with a biological nutrient system (MLE process using media), for a sewage treatment plant that has to treat dye wastewater efficiently with domestic wastewater were developed and a pilot plant was operated for verifying adoptability and performance of the developed advanced process for dye wastewater. From the results of the pilot plant operation, BOD 52.9%, $COD_{Cr}$ 55.9%, and color 71.3% were removed in pretreatment of coagulation process and the biodegradability of dye wastewater was improved to $0.32{\sim}0.59BOD/COD_{Cr}$ of the coagulated wastewater from $0.29{\sim}0.43BOD/COD_{Cr}$ of the raw dye wastewater. The final effluent concentrations were BOD of 8 mg/L, $COD_{Cr}$ of 43 mg/L, $COD_{Mn}$ of 18 mg/L, T-N of 8 mg/L, and T-P of 1.3 mg/L, respectively. Color was removed from 1655 to 468 unit by coagulation and then to 123 unit by MLE process. The HPLC analysis of aromatic amines in wastewater showed that decolorization was achieved by cometabolism while aromatic amines were produced by cleavage of azo bonds under anaerobic conditions and these products were removed in an aerobic tank subsequently. Nitrification rates of attached and suspended microorganisms were evaluated comparatively and the acclimating conditions of bacteria on media were validated by the scanning electron microscope.

• 대한환경공학회지
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• 제27권4호
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• pp.377-384
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• 2005

조류는 호소의 부영양화 현상을 발생시킬 뿐 아니라 전반적인 정수처리공정에 많은 문제를 야기 시키고 있다. 그 중에서도 조류 세포와 조류유래 유기물질(Algogenic Organic Matter; AOM)은 휴믹물질처럼 염소 소독 시 유해성 물질인 소독부산물질(Disinfection By-Products; DBPs)을 형성하는 전구물질이다. 본 연구는 전 염소처리와 응집공정에 의한 조류유래 유기물질의 제거특성 변화를 확인하였으며, 또한 부영양화된 호소수 처리 공정으로 철(III)을 이용한 고도응집공정과 UV산화 공정의 적용성을 평가하였다. 전 염소처리공정은 조류제거에는 효과적이지만 수중의 DOC(Dissoluble Organic Carbon)농도와 TMHs(Trihalomethanes) 생성량을 증가시켰다. 응집실험에서는 응집 반응 pH가 조류유래 유기물질과 소독부산물질 제거에 있어 중요한 인자로 작용하였으며, 중성 pH에서 보다 낮은 반응 pH 5에서 DOC, THMs 제거율이 각각 50%와 28% 향상되었다 조류유래 유기물질과 THMs제거에 있어 UV 산화 공정을 적용한 결과, $UV/H_2O_2/Fe^{3+}$ 공정이 가장 효과적이었지만, 반응 pH를 조정한 고도응집공정보다는 효과적이지 않았다.

• 한국환경과학회지
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• 제21권12호
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• pp.1523-1528
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• 2012

This study was carried out to develop pilot plant Net3FM(Net Fit Fiber Filter Module) system and to suggest optimum operating condition for municipal wastewater reuse. SS concentration of biologically treated sewage effluent was reduced from 1.5~5.4mg/L to 0.4~1.0mg/L without coagulant injection in Net3FM system, and the SS removal efficiency was average 84.7%. And also, the removal efficiencies of COD and T-P were decreased slightly due to the SS removal by filtration. Coagulation-Filtration test was conducted to enhance the removal efficiencies of SS and T-P. The optimum dosage of coagulant was injected automatically by auto-controlling system, which is controlled by detecting value of turbidity of secondary sewage effluent. SS, COD and T-P concentrations in filtrated effluent were 0.21~0.57, 1.6~6.2 and 0.137~0.392mg/L with coagulant injection by in-line mixer in Net3FM system, respectively. The removal efficiencies of SS and T-P were highly increased to 92.8% and 89.8%, respectively. It was due to the combined the processes of coagulation and filtration. Net3FM system was evaluated that the removal efficiency of pollutants in secondary sewage effluent and the utilization potential as reclaimed water technology were very high.

• 한국환경과학회지
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• 제20권5호
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• pp.639-645
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• 2011

This study found that flotation efficiencies for removing algae and micro particles in raw water were optimized on mixing intensity and time of the mixing and flocculation conditions with a continuous DAF system. It is more efficient for mixing intensity at 23.1 $s^{-1}$ and time at 660 s(Gt value : 15246) to float flocculated floc with the raw water in M water treatment plant. Flotation efficiency was more than about 0.9 when operated pressure and A/S ratio were sustained at 5 $kg_f{\cdot}cm^{-2}$ and up to 0.056 $mL{\cdot}mg^{-1}$. The continuous DAF system made by the study could be continuously operated for 20 days and sustained not exceeding 4 NTU with raw water with low turbidity(13.4~9.8 NTU).