• 상하수도학회지
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• 제22권2호
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• pp.267-274
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• 2008

This study is about efficiency of pretreatment process and operating factor to membrane process at continuous coagulation/ultrafiltration process in water treatment. The capacity of pilot plant was $0.06{\beta}(C)/d$. The raw water used was from Nakdong stream which was characteristized by high organic matter and high turbidity. The result of the test was that coagulation is good process as to high removal rate to organic matter and turbidity but It caused problem to membrane pore blocking. This paper is to determine the membrane fouling potential under different membrane flux, backwash pressure and linear velocity. Backwash pressure and flux is important parameter on operation of membrane system. Those are directly affected on membrane system. When backwash pressure increased from 150 kPa to 200 kPa, the result showed that fouling (pressure increase rate) changed from 3.69 kPa/h to 0.93 kPa/h and the recovery rate changed from 90.7 % to 82.0 %. Linear velocity had slightly effect on fouling. Linear velocity increased from 0.2 m/s to 0.5 m/s, the corresponding pressure rate changed from 0.93 kPa/d to 0.77 kPa/d.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.3139-3143
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• 2007

The objective of this paper was to investigate the mixing characteristics of an three-stage inline coagulant mixing system experimentally. Wastewater samples of pH 8.5 and initial turbidity 1,000NTU were taken from a site of tunneling work. At the constant dosage, 0.36mL/L, of polymer as coagulant aids, the coagulation efficiency with the dosage of PAC as coagulant was about 4${\sim}$6% at 10 minutes after sampling. In the case of 2 different velocity gradient conditions, the efficiency of turbidity removal was increased about 6.5${\sim}$8% with increasing the dosage of coagulant while, the efficiency was increased about 20${\sim}$21.5% with increasing the dosage of coagulant aids. The efficiency of turbidity removal with the settling time after sampling was about 90% after 1 minute, and the efficiency was about 95% after 5 minutes.

• 한국분무공학회지
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• 제11권2호
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• pp.98-104
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• 2006

A charged droplet scrubber was introduced to remove visible smokes generated in many industrial facilities. Lab-scale and field tests were conducted in this study. The system consists of a corona discharger to effectively charge the fine particles, fellowed by an electrostatic chamber to promote coagulation between charged fine particles and oppositely charged droplets and a demister to remove resultant particles. Overall collection efficiency, 98.4% was obtained from a lab-scale test, when a high voltage was applied to an ionizer and a charged droplet scrubber. Field tests also show the high collection efficiencies, 93.5% with one stage and 99.4% with two stage system. This system can be used to increase the collection efficiency of the conventional air pollution control devices to satisfy the national emission standard.

• 한국물환경학회지
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• 제28권2호
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• pp.300-304
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• 2012

It has a limitation to satisfy the phosphorus effluent criteria of 0.2 mg/L which will be reinforced from 2012 with the Biological Nutrient Removal (BNR) process. The chemical coagulation process has been operated in parallel with the biological treatment process for advanced treatment of phosphorous in the developed countries including Europe. However, the coagulation process has some disadvantages such as the desired goal may not be achieved without injecting the optimum dosage of the coagulant. This study developed the automatic control system to inject the optimum dosage of phosphorous coagulant into the coagulation process. The adopted coagulant was 10% Poly Aluminum Chloride (PAC) in this study. The automatic control system developed in this study was adopted for the treatment of the phosphorus from the effluent in SBR process. The automatic control system was composed of the data receiving part, the optimum coagulant dosage control part and the data transmit part. The result of the phosphorous advanced treatment of the SBR effluent using the automatic control system showed the removing efficiency over 95% consistently with the phosphorous concentration under 0.02 ~ 0.15 mg/L. The reproducibility analysis for checking the safety of automatic control system showed more than 95% correlation.

• 한국환경기술학회지
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• 제19권6호
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• pp.556-562
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• 2018

현재 하수종말처리장은 질소와 인의 방류수 수질기준 강화로 생물학적 처리 후 약품주입으로 잔류인의 처리를 하고 있는 실정에서 방류수 수질기준은 확보가 가능하나, 약품주입량의 과다와 발생되는 슬러지의 증대 및 발생슬러지의 탈수효율 저하로 슬러지처리과정에서 또 다른 문제가 발생하여 처리에 대한 신뢰성이 결여되어 있는 실정이다. 그러므로 본 연구는 기존 하수종말처리장에서 발생하고 있는 문제에 대하여 최소의 반응시간과 슬러지 발생량의 최소화를 토대로 생물학적 고도처리를 적용한 하수처리장에서 방류수 수질기준의 강화에 따라 생물학적 처리로 확보하기 어려운 안정적 처리방식과 처리수질변동에 대한 적응 및 질소와 인의 처리기준을 맞추기 위하여 기존 하수처리 방식에 Electro Coagulation and Oxidation system을 적용한 결과 다음과 같다. 1) Al-SUS(stainless steel)로 배치한 전극에서 반응시간대와 상관없이 $15mA/cm^2$의 전류밀도에서 BOD, TN 및 TP의 처리효율이 $5mA/cm^2$에서의 처리효율보다 높게 나타났으나, 전류밀도 $10mA/cm^2$ 이상만을 유지하여도 TP의 경우 대부분 0.1 mg/L 정도로 처리가 가능하며, 특히, 반응시간을 10 min으로 유지할 경우 TP농도는 전류밀도와 상관없이 0.06 mg/L 이하로 방류수 수질기준 0.1 mg/L 이하를 유지할 수 있었다. 2) TP농도의 변화는 전류밀도의 변화에 영향을 크게 받지 않으며, 오히려 반응시간에 따라 처리수의 농도가 변화하는 것으로 전기응집반응의 경우 수초~수분이 요구되나 전기산화와 동시에 반응이 일어나야 하므로 적절한 전기응집산화의 반응시간은 10 min 이상이 요구되는 것으로 연구되었다. 3) 결과적으로 본 연구에서 생활하수의 TN 및 TP처리를 위한 전기응집산화공정의 경제적인 전류밀도는 $15mA/cm^2$이하, 반응시간은 10 min을 유지하는 것이 적절한 것으로 연구되었다.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2001년도 추계학술대회 학술발표 논문집
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• pp.19-22
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• 2001

In this paper, Streaming Current Monitor (SCM), Pilot Filter (PF) and Coagulant Feeding System(CFS) for fuzzy neural network are used as a coagulation control method in WTP and the results are compared. Several parameters such as coagulant dosage, pH, and turbidity have been changed to find the response characteristic of each equipment. SCM, PF and CFS responded for certain parameters but the range of sensitivity was different each other. It is demonstrated that WTP will be operated more efficiently when SCM, PF and CFS are used as coagulation control strategy.

• 한국환경과학회지
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• 제15권9호
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• pp.829-834
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• 2006

This research aims to investigate the behavior of organic matter that causes bacterial re-growth and the formation of disinfectant by-products such as THM in water treatment, and to optimize conditions for a more efficient and conventional water facility. THM removed 51 % and 12 % through coagulation/sedimentation and filtration using a selected conventional system. In this experiment, the removal ratio of DOC was highest at 68 % when the Gt value was 42,000 and lowest at 41 % when the Gt value was 30,000. 77-84 % of total DOC was removed during coagulation/sedimentation, and 15-23 % was removed during filtration. When Gt values were between 30,000 and 66,000, over 50 % of high molecular matter above 10 K during coagulation/sedimentation was removed. Turbidity removed 98 % when the G1 value was 66,000. As the Gt value increased, the turbidity removal ratio increased. Turbidity removed over 20 % during the filtration process.

• Biomolecules & Therapeutics
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• 제9권4호
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• pp.258-262
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• 2001

In the advanced age, cardiovascular disease is more serious than any other disease. Especially, the thrombus causes the serious disease like apoplexia, carebri and myocardial infarction. Thrombosis is caused by the injury of endothelium and the alterations in normal blood flow. To investigate activities of Carthamus tinctorius L. Semen butanol fraction for blood coagulation system, endotoxin (4000EU/kg) was injected (i..v) to rats at 1hr after administration of Carthamus tinctorius L. Semen butanole fraction (500 mg/kg, p.o.). Carthamus tinctorius L. Semen butanol fraction was found to have antiplatelet activity in vitro. In vivo it showed a delay of blood clotting time, and prothrombin time, and reduction of fibrinogen and FDP It also increased SOD activity, and decreased MDA content. These results suggest that the antithrombosis effect of Carthamus tinctorius L. Semen butanol frac tion results from suppressive activity for a blood coagulation system and antioxidative activity.

• 상하수도학회지
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• 제20권4호
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• pp.487-498
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• 2006

The oxidation processes of metal catalysis were practically applied into the flexographic inks wastewater treatment to derive the most effective and economical system among all the processes of iron-salts coagulation, iron-catalyzed air oxidation, and coagulation followed by biological treatment. The iron concentration and pH were optimized as $2.8{\times}10^{-3}mol$ and 5.5~6.0, respectively, for all the oxidation processes. At the optimal reaction conditions, the removal efficiencies of $TCOD_{Mn}$ and Color were as follows for the respective process: i) 75% $TCOD_{Mn}$ and 77% Color removals for iron-salts coagulation, ii) 91% TCODMn and 90% Color removals for iron-catalyzed air oxidation, iii) 74~92% $TCOD_{Mn}$ and 81~90% Color removals for coagulation followed by biological treatment. Based on the economical and technological aspects, iron-catalyzed air oxidation was confirmed as the most effective process in the treatment of industrial wastewater.

• 대한환경공학회지
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• 제27권8호
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• pp.837-843
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• 2005

한외여과 공정의 전처리 공정으로 응집을 적용하였으며, 막여과 공정에 미치는 응집공정의 영향을 평가하였다. 예상되는 응집 효과는 수질 개선, 막오염 저감 및 역세척 효율 향상 등이며, 응집 한외여과 막여과 공정을 연속운전을 통해 조사하였다. 이때 적용된 응집제는 황산반토, PACS, 염화제2철이다. 연구 결과 응집을 통해 처리수 수질을 크게 향상 시킬 수 있었으며, 현탁물질 보다는 유기물 제거율에 높은 효과가 있었고, 최대 30.6%의 제거율 향상을 나타내었다. 막오염 저감에 있어서는 세 종류의 응집제 모두 뚜렷한 효과를 관찰할 수 있었으며, 특히 장기운전에 TA어서 PACS가 가장 효과적이었다. 역세척 효율은 철염응집제가 가장 효과적이었으며, 적정 응집제 주입량에 가까울수록 효율이 향상되는 것으로 나타났다.