• 한국산업융합학회 논문집
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• 제9권2호
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• pp.111-116
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• 2006

This study provides the optimal conditions treating with the coagulation process and the other chemical treatment processes for dyeing wastewater, especially various dyeing complex wastewater. The results are shown as follows: 1. Optimum reaction condition of pH for ferrous sulfate was the range of 9 to 12. And when 3,000ppm(mg/l) of ferrous sulfate was dosed, the maximum $COD_{Mn}$ removal rate was approximately 40%. 2. In case of ferrous chloride and Bittern as coagulants, optimum pH range was 10 to 11. And maximum $COD_{Mn}$ removal rate was approximately 46% to 50% for dose of 2,000ppm(mg/l) to 6,000 ppm. 3. It is confirmed that the activated sludge process following coagulation precipitation method provides better treatment efficiency than the coagulation precipitation method following the activated sludge process. 4. The purpose of this study was to produce CGF (Cyanoguanidineformaldehyde resin) by organic compounds. 5. The complex coagulation agent by this study is the most economical coagulant with Alum(aluminum sulfate) and the removal efficiency is approximately 54% with 1,000ppm(mg/l) of pH range 6 to 7.

• 청정기술
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• 제8권2호
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• pp.61-66
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• 2002

알루미늄 제조 공정에서 부산물로 발생되는 적니와 제지슬러지를 이용하여 휘발성 유기화합물을 제거하기 위한 흡착제 개발 연구를 수행하였다. 흡착제의 제조를 용이하게 하기 위해 고밀도폴리에틸렌과 저밀도폴리에틸렌을 이용하였다. 흡착제에 고밀도폴리에틸렌을 사용한 것이 저밀도폴리에틸렌을 사용한 것 보다 비표면적 값이 높아서 흡착량이 증대되었다. 제조된 흡착제의 비표면적 값이 활성탄과 비교하여 상대적으로 매우 낮은 값 ($10^{-2}$에서 $10^{-3}$ 정도)을 가졌는데 이는 흡착제 제조시 제지슬러지를 완전히 분해하는데 충분한 시간을 주지 못하였기 때문으로 생각된다. 그러나 제조된 흡착제의 흡착용량(단위 표면적당 흡착량)은 활성탄에 비하여 약 10배에서 100배 정도의 높은 값을 가졌다. 그러므로 제조된 흡착제가 활성탄과 같은 성능을 갖기 위해서는 비표면적을 증대시키는 것이 중요하다.

• 상하수도학회지
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• 제20권1호
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• pp.128-137
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• 2006

This study aims at developing the practical technology in the treatment of box-mill wastewater using the aerobic co-metabolism principle. The conventional activated sludge method exhibited the removal efficiency of $TBOD_5$ and $TCOD_{Mn}$ as 30~50% and 40~50%, respectively. Color was rather increased by 30~130% because the conventional treatment under the aerobic condition did not induce the conversion of molecular structure of dyeing agents. Meanwhile, when the aerobic co-metabolism principle was applied to the same wastewater, the removal efficiency of $TBOD_5$ and $TCOD_{Mn}$ were obtained as 92~97% and 90~94%, respectively. In particular, color was significantly reduced down to 65~85%. The enhancement of treatment efficiency was ascribed to occur not only that the non-degradables were converted to the second substrates, but also that the enzyme activity was increased as MLVSS was kept 3000mg/l or more with the first substrates injected.

• Biotechnology and Bioprocess Engineering:BBE
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• 제2권2호
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• pp.136-140
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• 1997

Direct membrane separation using nonwoven fabric was applied to saline wastewater treatment by an activated sludge process. A nonwoven fabric module was immersed in an aeration tank. The part of treated was filtered through the module by suction and the rest of that was separated by a settling tank. Various F/M ratios and salt concentrations were applied to investigate stable flux as well as pollutant removal. The pollutant removal efficiencies of nonwoven fabric separation was not affected by F/M ratios and salt concentrations and was higher than that of settling tank separation. The decline in flux was seemed to be caused by the biofilm on nonwoven fabric surface.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권6호
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• pp.335-339
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• 2002

Laboratory experiments were conducted using pure cultures of Acinetobacter under an-aerobic/aerobic cyclic conditions to explain the release and uptake of soluble phosphate in an activated sludge process showing enhanced biological phosphate removal (EBPR). Under anaerobic/aerobic cyclic conditions in a Sequencing Batch Reactor (SBR), COD uptake concurrent with soluble phosphate release by Acinetobacter was not significant during the anaerobic periods, indicating that EBPR would not be established in pure cultures. However Acinetobacter cells accumulated higher phosphate content (5.2%) in SBR than that obtained (4.3%) from batch experiments. These results suggest that Acinetobacter sp. may not follow the proposed pattern of behavior of poly-P bacteria in EBPR activated sludge Plants.

• 한국환경과학회지
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• 제13권2호
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• pp.161-165
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• 2004

This study has been conducted to develop a new recycling technology of sewage sludge using a carbonization process. The carbonizing yield, the calorific value and EC(electric conductivity) of carbonized sewage sludge had a tendency to be decreased with increase of the carbonizing temperature and time, but pH and the C/N were increased with increase the carbonizing temperature and time. The whole pore volume of carbonized sludge processed in the carbonizing furnace was /g, which was smaller than that in the electric furnace. But, the rates of mesopore and macropore were found to account for 100% therein. Rate of color and organic materials removal for dyeing wastewater were determined 70~97%, 78~83% on cotton yarn, 88~96%, 69~80% on wool wastewater and 77~89%, 77~87% on towel compared with powder activated carbon. Effect of carbonized sludge on chrysanthemum growth was investigated. Plant height and number of leaves was better mixture of carbonized sludge than comparison.

• 한국환경보건학회지
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• 제20권3호
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• pp.1-12
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• 1994

Wastewaters being treated and final effluents were collected from 3 wastewater treatment plants of petrochemical industries, from August 31 to October 4, 1993 in an interval of 10 days, and further analysed by GC/FID to investigate discharge situation and removal efficiency on polycyclic aromatic hydrocarbons. The results were as follows: 1. The PAHs 294.57 $\mu$g/l were discharged in primary treatment effluent of plant A to manufacture vinyl acetate resin and acryl, and removed 54.51% by aeration and totally 84.71%. 2. The PAHs of the highest concentration were discharged in primary treatment effluent of plant B to manufacture PS resin and ABS resin, but removed 91.65% by activated sludge process and 98.19% by activated carbon to discharge PAHs of the lowest concentration comparing to another treatment operations. 3. The PAHs 99.96 $\mu$g/l of the lowest concentration were discharged in wastewater of plant C to manufacture epoxy resin, and removed 80.48% by activated sludge process. 4. B treatment system including activated carbon showed up the best removal efficiency of PAHs. Activated carbon therefore, seems to be effective as tertiary treatment. 5. Correlation coefficient of components to total PAHs was generally low, and correlation coefficients of phenanthrene, pyrene and acenaphthylene to total PAHs were each 0.98, 0.97 and 0.80, respectively. Correlation coefficient of the sum of phenanthrene, pyrene and acenaphthylene to total PAHs was 0.99, so that the sum of phenanthrene, pyrene and acenaphthylene was available as index to estimated total PAHs. 6. Phenanthrene and Chrysene were very well treated biologically and acenaphthylene and fluoranthene were untreated biologically. 7. Considering EPA standards, it seems that the concentration of phenanthrene, pyrene, fluoranthene, and benzo(k)fluoranthene is high level.

• 생명과학회지
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• 제21권10호
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• pp.1473-1480
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• 2011

퍼클로레이트($ClO_4^-$)는 지표수 및 토양/지하수에서 검출되는 오염물이다. 미생물은 퍼클로레이트를 무해한 최종산물로 환원시킬 수 있으므로 퍼클로레이트제거는 미생물을 이용한 방법이 가장 적절한 것으로 알려졌다. 미생물이 퍼클로레이트를 환원시키기 위해서는 전자 공여체가 필요하다. 퍼클로레이트를 환원하기 위한 기존의 기술들은 전자 공여체로서 유기물을 사용하는 종속영양방식의 퍼클로레이트환원세균을 사용한다. 그래서 종속영양 방식으로 퍼클로레이트를 연속 제거하기 위해서는 지속적으로 유기물을 공급해야 하므로 처리비용이 많이 든다. 본 연구에서는 원소 황 입자와 활성 슬러지를 이용하여 독립영양방식의 퍼클로레이트제거가능성을 조사하였다. 입자상 황은 비교적 값이 저렴하고 활성 슬러지는 하수처리장으로부터 쉽게 구할 수 있는 장점이 있다. 회분배양 실험결과 활성 슬러지 미생물은 전자 공여체로서 황 입자가 존재할 때 퍼클로레이트를 제거할 수 있다는 것이 증명되었다. 이러한 퍼클로레이트 분해는 퍼클로레이트가 분해됨에 따라 생성되는 Cl-의 몰 농도를 통해 검증할 수 있었다. 독립영양방식의 $ClO_4^-$ 제거공정에 사용된 황 입자의 표면에 간균 형태의 미생물들이 존재한다는 것을 주사전자현미경을 통해 관찰하였다. 그래서 황 입자가 생물막을 형성하기 위한 담체로도 작용할 수 있다는 것을 알 수 있었다. 황입자가 첨가된 $ClO_4^-$ 분해성 농화 배양으로부터 채취한 생물막의 미생물군집조성은 접종균으로 사용된 활성 슬러지의 그것과는 다름이 DGGE 분석결과 나타났다.

• 상하수도학회지
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• 제26권6호
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• pp.897-905
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• 2012

Based on the activated sludge model, a simple aerobic digestion model which represents the aerobic sludge digestion by sequencing batch reactor(SBR) equipped with ultrasonicator was composed and performed in this study. The results are as follows. Aerobic digestion efficiency can be increased by adopting ultrasonic pretreatment. For the 5 days of SRT, 24 % of particulate component is predicted to be removed by ultrasonic pretreatment and aerobic digestion. This is 7 %p higher than that of conventional aerobic digestion. A Hybrid SBR aerobic digestion combined with ultrasonication shows higher digestion efficiency than aerobic digestion and ultrasonic pretreatment system. In case of this hybrid system, the digestion efficiency was predicted up to 49 % when the ultrasonication was performed every 2 hours, repeatedly. However, excessive treatment like every hours of ultrasonication in an aerobic digestion process results in adverse effect on TCOD removal because biomass disintegrated completely and the solubilized COD can not be used for the biomass synthesis again.

• 청정기술
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• 제7권1호
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• pp.35-42
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• 2001

본 연구에서는 zeolite를 활성슬러지 공정에 주입할 경우 zeolite가 biofloc에 미치는 영향에 대해 알아보기 위해 수행되었다. 두 반응기를 동일 조건으로 운전하였으며 하나는 표준 활성슬러지 공정 (CU)으로, 다른 하나는 zeolite를 폭기조내 4,000 mg/l로 유지 (ZU)하며 비교하였다. 슬러지 플럭 입경을 측정한 결과, 두 반응기 모두 SRT (Solid Retention Time)가 증가함에 따라 플럭 크기도 비례하여 증가하였으나 ZU가 모든 조건에서 CU보다 작은 평균 입경을 나타내었다. 한편, 두 반응기에 대해 슬러지 침전성을 비교한 결과, ZU는 SRT변화에 관계없이 3.4~11m/h의 침전속도를 나타내며 SVI(Sludge Volume Index)도 50~108 ml/g으로 양호한 침전상태를 보였다. 그러나 CU는 SRT 증가에 따라 슬러지 침전성이 큰 영향을 받았고 SRT 40일에서 Sphaerotilus가 우점종을 나타내었으며 이 결과, 슬러지가 전혀 침전하지 않았다.