• 한국물환경학회지
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• 제20권6호
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• pp.692-697
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• 2004

Biological phosphorus removal is characterized by complex interactions between different intracellular components of energy as PHA. Therefore, fundamental understanding of the behavior of the intracellular components and their influence on the removal of phosphorus is essential before control strategies to stabilize the proper process. The purpose of this study is to investigate relationship between release of phosphorus and synthesis of intracellular storage polymer. Mass of stored intracellular storage polymer was 21.2 mg PHA/L, 28.8 mg PHA/g MLSS. And phosphorus release/intracellular storage polymer synthesis rate was 1.8545 mg stored polymer/mg Phosphate. In the aerobic phase, mass of PAOs synthesis is 49.37 mg PAOs/L. And PAOs fraction was 6.7-6.9%. Thus intracellular storage polymer synthesis by PAOs is calculated as 493mg PHA/g PAOs.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2019년도 정기학술대회 발표논문집
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• pp.134-134
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• 2019

Utilization of organic waste as a renewable energy source is promising for sustainability and mitigation of climate change. Pyrolysis converts organic waste to gas, oil, and biochar by incomplete biomass combustion. Biochar is widely used as a soil conditioner and adsorbent. Biochar adsorbs/desorbs metals and ions depending on the soil environment and condition to act as a nutrient buffer in soils. Biochar is also regarded as a carbon storage by fixation of organic carbon. Phosphorus (P) and nitrogen (N) are strictly controlled in many wastewater treatment plants because it causes eutrophication in water bodies. P and N is removed by biological and chemical methods in wastewater treatment plants and transferred to sludge for disposal. On the other hand, P is an irreplaceable essential element for all living organisms and its resource (phosphate rock) is estimated about 100 years of economical mining. Therefore, P and N recovery from waste and wastewater is a critical issue for sustainable human society. For the purpose, intensive researches have been carried out to remove and recover P and N from waste and wastewater. Previous studies have shown that biochars can adsorb and desorbed phosphates implying that biochars could be a complementary fertilizer. However, most of the conventional biochar have limited capacity to adsorb phosphates and nitrate. Recent studies have focused on biochar impregnated with metal salts to improve phosphates and nitrate adsorption by synthesizing biochars with novel structures and surface properties. Metal salts and metal oxides have been used for the surface modification of biochars. If P removal is the only concern, P adsorption kinetics and capacity are the only important factors. If both of P and N removal and the application of recovery are concerned, however, P and N desorption characteristics and bioavailability are also critical factors to be considered. Most of the researches on impregnated biochars have focused on P removal efficiency and kinetics. In this study, coffee waste is thermally treated to produce biochar and it was impregnated with Mg/Al to enhance phosphates and nitrate adsorption/desorption and P bioavailability to increase its value as a fertilizer. Kinetics of phosphates and nitrate adsorption/desorption and bioavailability analysis were carried out to estimate its potential as a P and N removal adsorbent in wasewater and a fertilizer in soil.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.231.2-231.2
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• 2003

The efficient EPO (Erythropoietin) expression system in Chinese Hamster Ovary (CHO) cells was devised through the removal of ammonium ion accumulated in the media by introducing urea cycle enzymes. Previously, we developed C05 cell by transfecting the carbamoly phosphate synthase (CPS) and ornithine transcarbamoylase (OTC) into the EPO expressing CHO cell, IBE. (omitted)

• 한국환경과학회지
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• 제13권7호
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• pp.675-680
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• 2004

This study was conducted to remove organics and nutrients using 2 stage intermittent aeration reactor. First reactor, using suspended microbial growth in intermittent aeration instead of anaerobic reactor in the typical BNR process, used minimum carbon source to release P, and it was possible to reduce ammonia loading going to second reactor. In the second reactor, using moving media intermittent aeration, it was effective to reduce nitrate in non-aeration time by attached microorganisms having long retention time. In aeration time, nitrification and P uptake were taken place simultaneously. From the experiment, two major results were as follows. First, the removal of organics was more than 90%, and optimum aeration/non-aeration time ratio for organic removal was corresponded with aeration/non-aeration time ratio for nitrogen removal. Second, in the first reactor, optimum aeration/non-aeration time ratio was 15/75 (min.) because it was necessary to maintain 75 min. of non-aeration time to suppress of impediment of return nitrate and to lead release of phosphate. In the second reactor, optimum aeration/non-aeration time ratio was 45/90 (min.).

• 한국초전도ㆍ저온공학회논문지
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• 제23권3호
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• pp.20-25
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• 2021

Milking parlor wastewater contains high concentration suspended solid (SS), nitrogen, and/or phosphate as well as organic compounds. A new biological wastewater process by magnetic separation, magnetic activated sludge (MAS) process, was applied to milking parlor wastewater treatment process. A three step wastewater treatment process of coagulation sedimentation / ammonia stripping (C/S), magnetic activated sludge process and contact oxidation (CO) was proposed for removal of these pollutants. First step, C/S process recovered 96% TN and 96% PO₄^3--P as resource for fertilizer from the wastewater. 81% biochemical oxygen demand (BOD) in wastewater was removed after MAS process. As a results, all pollutant concentrations satisfied Japanese effluent standards. Most of residual BOD and SS were removed by the CO process. It was estimated that the proposed process could reduce the process space to 1/7.

• 대한환경공학회지
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• 제22권5호
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• pp.939-947
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• 2000

연속 회분식 반응기를 이용하여 생물학적 인 제거에 관한 미생물 분포 연구를 수행하였다. 탄소원으로 초산을 넣은 합성 폐수를 사용하였고 미생물 체류 시간과 수리학적 체류 시간은 각각 10일과 16시간으로 유지하였다. 인 방출과 흡수가 운전 시간이 경과됨에 따라 점점 빠르게 일어났으며 약 200일 경과 후 안정적인 인 제거가 유지되었다. 안정적인 생물학적 인 제거가 유지될 때의 미생물 분포를 조사하기 위하여 17개의 ribosomal RNA (rRNA) signature probe를 합성하여 슬러지로부터 분리한 전체 rRNA에 대하여 slot hybridization을 실시하였다. 분리한 전체 RNA에는 proteobacteria의 베타군 (beta subclass)에 속하는 rRNA가 가장 많이 함유되어 있음을 확인하였고 CTE probe와 관계된 rRNA가 다음으로 많이 분포하였다. 전통적으로 생물학적 인 제거를 담당하는 미생물로 여겨져 왔던 Acinetobacter, Aeromonas, Pseudomonas의 rRNA는 10% 미만으로 존재하고 있음이 확인되었다. 이러한 결과로부터 Rhodocyclus 그룹같은 proteobacteria의 베타군과 CTE에 속하는 미생물이 인 제거에 중요한 역할을 수행할 것으로 생각되었고 Acinetobacter, Aeromonas, Pseudomonas 등은 생물학적 인 제거에 있어서 과평가된 것으로 판단되었다.

• 대한환경공학회지
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• 제22권3호
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• pp.587-595
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• 2000

국내 하수처리장에 적용되는 BNR(Biological Nutrients Removal) 공정의 효율저하 원인은 유입원수의 낮은 C/N비와 탄소 (Carbon source) 부족이 가장 큰 것으로 지적되어 왔다. 탄소원의 효율적인 공급을 위해 1차 슬러지 산 발효조(Acid fermenter)를 이용하여 SCFAs(Short-Chain Fatty Acids) 생성을 유도할 수 있다. 본 연구에서는 side-stream의 산 발효조와 조합된 $A_2/O$ 프로세스를 운전하여 영양염류 제거에 미치는 영향을 연구하였다. 그 결과 산 발효조의 최대 SCFAs생성은 중온상의 SRT 4~5일에서 약 3.000mg/L(as COD), 대략 0.10~0.16 mg SCFA(as COD)/mg 1차 슬러지(as COD)로 나타났다. 또한 생성된 SCFAs의 성상비는 Acetic, Propionic, (iso)Butyric 및 (iso)Valeric이 1, 0.7, 0.5 그리고 0.6 순으로 나타났다. BNR공정의 side-stream 산 발효조 적용에 의한 영양염류 제거효율은 크게 증가하는 것으로 나타났다. T-N은 인공하수(R1)의 경우 35% 정도의 낮은 처리효율을 나타냈으나 인공 SCFA 주입(R2) 및 발효산물 투입(R3)의 경우 제거효율 74%, 76%로 크게 향상되는 것으로 나타났다. 또한 Phosphate 는 R1의 경우 45% 의 처리효율을 나타냈으나 R2, R3의 경우 73~74% 정도로 양호한 처리효율을 나타냈다. 이는 발효산물 및 SCFA 주입에 의해 혐기조에서 인의 방출 및 호기조에서 과잉섭취가 잘 이루어졌기 때문으로 R3의 경우 인의 방출율은 $0.34g\;PO_4-P/g$ COD로 기존 연구와 비교해서 유사한 것으로 나타났다.

• 상하수도학회지
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• 제22권2호
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• pp.179-182
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• 2008

The KIDEA process, occurred in single reactor, is operated by three consequential steps, i.e., aerobic, settling, and discharge while introducing wastewater into the bottom of reactor continuously. It could accomplish biological oxidation (BOD), nitrification, denitrification (T-N), phosphate removal (T-P), and solid separation (SS) through the operational mode mentioned. Especially, this system has removed the T-P by wasting certain amount of sludge at the end of aeration phase during 5~10 minutes and not returned the activated sludge into the reactor, that is, no RAS (Return Activated Sludge). All running mode and instrumentation were controlled by the PLC equipment automatically. In this study, therefore, we have evaluated T-P removal efficiency and moisture content (MC) performance under the different excess sludge wasting mode. T-P track study and MC with TS concentration were analyzed during aerobic and settling phase. It has revealed that there was no significant difference of released T-P concentration between the first case which waste the sludge at the end of aerobic phase (0.2mg/L) and the second case which waste the sludge at 40 min of settling phase (0.25mg/L). Also, dewatering duration and MC have decreased 1.7% when TS concentration was increased from 0.31% to 0.5% during aerobic condition. Hence, it has concluded the system performance was less influenced by the operation time change of PLC program.

• Applied Biological Chemistry
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• 제20권3호
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• pp.300-309
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• 1977

The information related to the heavy metal pollution in the environment was obtained from studies on the effects of pH, phosphate and soil properties on the adsorption of metal ions (Cd, Cu, Ni, and Zn) by soils. Three soil materials; soil 1 with low CEC (8.2 me/100g) and low organic carbon content (0.34%); soil 2 with high CEC (36.4 me/100g) and low organic carbon content (1.8%) and soil 3 with high CEC (49.9 me/100g) and high organic carbon content (14.7%) were used. Soils were adjusted to several pH's and equilibrated with metal ion mixtures of 4 different concentrations, each having equal equivalents of each metal ion (0.63, 1.88, 3.12 and 4.38 micromoles per one gram soil with and without 10 micromoles of phosphate per one gram soil). Reported here are the results of the equilibrium study on soil I. The rest of the results on soil 2 and soil 3 will be repoted subsequeutly. Generally higher metal ion concentration solution resulted in higher final metal ion concentrations in the equilibrated solution and phosphate had minimal effect except it tended to enhance removal of cadmium and zinc from equilibrated solutions while it tended to decrease the removal of copper and nickel. In soil 1, percentages of added metal ions removed at pH 5.10 were; Cu 97, Ni 69, Cd 63, and Zn 55, while increasing pH to 6.40, they were increased to Cu 90.9, Zn 99, Ni 96, and Cd 92 per As initial metal ion concentration increased, final metal ion concentrations in the equilibrated solution showed a relationship with pH of the system as they fit to the equation $p[M^{++}]=a$ pH+b where $p[M^{++}]=-log$[metal ion concentration in Mol/liter]. The magnitude of pH and soil effects were reflected in slope (a) of the equation, and were different among metal ions and soils. Slopes (a) for metal ions in the aqueous system are all 2. In soil 1 they were; Zn 1.23, Cu 0.99, Ni 0.69 and Cd 0.59 at highest concentration. The adsorption of Cd, Ni, and Zn in soil 1 could be represented by the Iangmuir isotherm. However, construction of the Iangmuir isotherm required the correction for pH differences.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 추계학술대회
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• pp.147-152
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• 2004

선박에서 발생되는 오${\cdot}$폐수를 처리하기 위하여 생물학적 영양염류 제거공정에서 질소와 인 등의 제거효율은 유기물의 양과 구성성분에 따라 영향을 받는 경향이었다. 선박에서 발생되는 음식폐기물을 이용하여 생성된 산발효액을 이용하여 영양염류를 효율적으로 제거하기 위한 외부탄소원으로 사용하여 산발효액의 적용성을 평가하였다. 음식폐기물 산발효액의 탈질율을 평가한 결과 질산성 질소가 완전히 제거되는 시간은 140분이였고, 탈질속도는 0.30g $NO_3-N/g\;VSS{\cdot}day$로 나타났다. 산발효액의 주입으로 인하여 유출수 중의 $COD_cr$ 농도가 증가함을 알 수 있었는데 이것은 산발효액에 존재하는 유기물을 미생물이 다 이용하지 못하는 부분이 존재하고 주입량의 증가에 따른 유출수 중의 $COD_cr$ 농도를 증가시켰다. 암모니아성 질소의 성상은 산발효액의 첨가에 크게 영향을 받지 않았으며 산화된 질소의 변화는 산발효액 주입량이 증가할수록 무산소단계에서 농도가 감소하여 전체 제거효율이 증가함을 볼 수 있었다.