• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 국제학술대회
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• pp.406-409
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• 2005

Since 2003, Korean government has restricted landfill application of organic waste, which shares approximately 56% of total waste sludge from municipal and industrial wastewater treatment plants. In addition, enforcement of the ocean disposal prohibition law is effective from 2005. Organic sludge was composted for the purpose of converting to organic fertilizer. After moisture content was regulated with bulking agents aerobic treatment performed. When composting was conducted, commercial and activated microbe materials, identified from soil were seeded in sewage sludge. Carbon dioxide production was increased sharply after 24 hours. Temperature and pH of compost reached to $66.2^{\circ}C$ and 8. Heavy metals were lower than their regulatory limits, which enable it to utilize as organic fertilizer.

• Carbon letters
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• 제4권2호
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• pp.64-68
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• 2003

A study on the electrosorption of uranium ions onto a porous activated carbon fiber (ACF) was performed to treat uraniumcontaining lagoon sludge. The result of the continuous flow-through cell electrosorption experiments showed that the applied negative potential increased the adsorption kinetics and capacity in comparison to the open-circuit potential (OCP) adsorption for uranium ions. Effective U(VI) removal is accomplished when a negative potential is applied to the activated carbon fiber (ACF) electrode. For a feed concentration of 100 mg/L, the concentration of U(VI) in the cell effluent is reduced to less than 1 mg/L. The selective removal of uranium ions from electrolyte was possible by the electrosorption process.

• 대한환경공학회지
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• 제29권9호
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• pp.1044-1050
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• 2007

본 연구는 대표적인 유기성 폐기물인 음식물쓰레기와 폐활성슬러지를 처리함과 동시에 수소를 생물학적인 방법으로 생성하기 위하여 운전인자인 가용화 방법, pH, VFAs 및 음식물쓰레기와 폐활성슬러지의 최적 혼합비율을 도출하고자 하였다. 폐활성슬러지의 수소 생성량을 높이기 위해 다양한 가용화 방법을 적용하여 그에 따른 수소 수율을 비교한 결과 알칼리와 초음파처리 한 병합처리에서 4.3 mL $H_2/g$ $VS_{consumed}$로 가장 높았으며, 음식물쓰레기와 가용화 된 폐활성슬러지를 혼합한 경우에도 병합처리 한 가용화 방법에서 수소 수율이 13.8 mL $H_2/g$ $VS_{consumed}$로 가장 높았다. 또한 pH는 $5.0\sim5.5$에서 운전시 가장 높은 수소 생성량을 보였으며, 음식물쓰레기와 가용화 된 폐활성슬러지의 최적 혼합비율은 2 : 1에서 수소 생성량이 5.0 L $H_2/L/d$로 가장 높았다. 생물학적 수소 생성이 많을수록 VFAs는 프로피온산의 농도가 낮았고, 부티르산이 아세트산보다 높은 비율로 생산되었다.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 Proceedings of KSEH.Minamata Forum
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• pp.51-53
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• 2005

Disposal of waterwork sludge is important problem in WTP(water treatment plant). Purpose of this study is treated municipal waste water chemically using sludge that is produced in waterwork plant by link to reutilize waterwork sludge. Municipal waste water that use in an experiment used is produced at C university, and is SS 220 mg/L, BOD 145 mg/L, COD 160 mg/L, T-N 52 mg/L and T-P 2.6 mg/L. Used Alum, polymer coagulant and coagulant aid (diatomite, powered activated carbon) as CaO, coagulant as alkaline aid by chemical treatment medicine. In case of does slow speed agitation and stations after pours waterwork sludge in sewage and alkaline aid and coagulant at rapidly mixing the colloidal creation speed is fast and fine colloids concentration was high but settling time is shortened a little and removal rate of pollutant improved by $60{\sim}99%$.

• Environmental Analysis Health and Toxicology
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• 제29권
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• pp.15.1-15.7
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• 2014

Objectives This paper tried to review a recent research trend for the environmental exposure of engineered nanomaterials (ENMs) and its removal efficiency in the nanowaste treatment plants. Methods The studies on the predicted environmental concentrations (PEC) of ENMs obtained by exposure modeling and treatment (or removal) efficiency in nanowaste treatment facilities, such as wastewater treatment plant (WTP) and waste incineration plant (WIP) were investigated. The studies on the landfill of nanowastes also were investigated. Results The Swiss Federal Laboratories for Materials Science and Technology group has led the way in developing methods for estimating ENM production and emissions. The PEC values are available for surface water, wastewater treatment plant effluents, biosolids, sediments, soils, and air. Based on the PEC modeling, the major routes for the environmental exposure of the ENMs were found as WTP effluents/sludge. The ENMs entered in the WTP were 90-99% removed and accumulated in the activated sludge and sludge cake. Additionally, the waste ash released from the WIP contain ENMs. Ultimately, landfills are the likely final destination of the disposed sludge or discarded ENMs products. Conclusions Although the removal efficiency of the ENMs using nanowaste treatment facilities is acceptable, the ENMs were accumulated on the sludge and then finally moved to the landfill. Therefore, the monitoring for the ENMs in the environment where the WTP effluent is discharged or biomass disposed is required to increase our knowledge on the fate and transport of the ENMs and to prevent the unintentional exposure (release) in the environment.

• 수산해양기술연구
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• 제17권1호
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• pp.41-47
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• 1981

The characteristics of septic tank sludges were investigated and the kinetic coefficients in the aerobic biodegradation were evaluated from bach treatability tests. Using an unbiased statistical method, the estimated values, k (substrate removal rate coefficient) =0. 0175hr-1 at 17\ulcornerC, K. (Michaelis Menten constant) = 248mg/ e, a (cell yield coefficient)=0.625, and Kd (cell decay coefficient:' =0. 00192hr-1 were obtained based on biodegradable COD(mg/ \ulcorner) and volatile suspended solids(mg/\ulcorner). The relationship between COD and BOD, COD (mg/\ulcorner) =2. 1 BOD(mg/\ulcorner) +250, also was established for the septic tank sludges. Dilution was inevitable for the grit removal because of the high viscosity of the sludges. An aerobic activated sludge process rather than anaerobic processes was recommended for the removal of soluble organics after the removal of grit and suspended solids. A multi-stage activated sludge process was adapted for this highly concentrated and not easily-degradable waste. It was estimated that a four-stage activated sludge process would require 40 hours retention time compared to 92 hours for a single-stage process, 52 hours for a double-stage process, and 46 hours for a three stage process in order to achieve an effluent quality of 84mg/ e COD( 40mg/ e BOD) with about 4, OOOmg/ \ulcorner MLSS from an influent quality of I, 500mg/ t COD(714mg/.e BOD), while multi-stages beyond four stage would not save the required retention time significantly.

• Membrane and Water Treatment
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• 제9권3호
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• pp.147-153
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• 2018

This study investigates the role of microbial extracellular polymeric substances (EPSs) as bioflocculants to harvest microalgae (water-microalgae separation). The EPS extracted from waste activated sludge (WAS) by heat extraction were fractionated into soluble EPS (S-EPS), loosely-bound EPS (LB-EPS) and tightly-bound EPS (TB-EPS) forms. All the EPSs facilitated the flocculation of microalgal cells from stable growth medium. Of those EPSs, the TB-EPS showed the highest flocculating activity (FA) resulting in the substantial decrease in the amount of EPS added in terms of total organic carbon (TOC) during flocculation. The FA of microalgae was improved with the increase in TB-EPS dose, however, excessive dose of TB-EPS adversely affected it due to destabilization. Both LB- and TB-EPS could be utilized for flocculating microalgae as a sustainable option to the existing chemical-based flocculants. In addition to the conventional assessments, the effectiveness of the two bioflocculants for floc forming was also confirmed using a novel assessment of lens-free shadow imaging technique (LSIT), which was firstly applied for the rapid and quantitative assessment of microalgal flocculation.

• 수산해양기술연구
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• 제14권1호
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• pp.43-54
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• 1978

생물학적 폐수처리 공법중 활성 슬러시지 공법의 수학적 해법에 관한 연구는 Michaelis-Menton, Monod, Eckenfelder, McKinney 등에 의하여 개발되어왔다. 이들에 의해서 개발된 수학적 모델은 각기 연구되어 온 측면이 서로 다르고, 사용된 기호가 상이하기 때문에 사용자로 하여금 많은 혼란을 주고 있다. 본연구는 각기 수학적 모델을 이론적, 단편적으로 분석하고, 각기 모델에서 사용된 기호의 상호관계를 비교하여 각기모델을 통일시켜 사용자가 이해하기 쉽도록 노력하였다. 실제로 모형실험에는 Aeration Only Activated Sludge 공법을 채택하고 시료는 Glutamic acid 폐수로 행하였다. 실제로 처리하여 얻어진 결과치와 각기모델의 계산치를 1) 유기물제거속도 2) 슬럿지생산비 3) 유출수에 관리되지 않고 남은 유기물농도 4) 폭기조내 산소요구량에 대하여 비교 검토하였다. 본연구에서 시행한 운전결과와 그분석으로부터 McKinney와 Eckenfelder의 모델은 활성슬럿지공법의 생물학적 관리시설의 설계요소들을 모두 구할수 있으나 Michaelis-Menton과 Monod의 모델은 모든 요소들을 구할수 없다.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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• pp.1102-1105
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• 1993

A fuzzy expert system for prediction and mitigation of sludge bulking was developed for an activated sludge process which treats waste water from a food industry. The developed system is able not only to infer the degree of progress of sludge bulking but also to generate remedial operation guides which may be sent to the local controllers as remote set points. One of the important consequences through this study is the BI (Bulking Index) inferred by the bulking prediction expert system was found to have a close correlation with the SVI (Sludge Volume Index) which is a practical measure of degree of bulking but needs tedious chores for its measurement.

• 유기물자원화
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• 제13권3호
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• pp.71-81
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• 2005

슬러지를 안정화시키기 위하여 가장 많이 적용되고 있는 공법은 혐기성 소화공법이라고 할 수 있다. 또한, 혐기성 소화는 유기성분의 효과적인 안정화와 동시에 메탄가스를 발생시켜 에너지로 이용 가능하다는 장점을 가지고 있다. 그러나, 폐활성슬러지의 경우 미생물의 세포벽 때문에 일반적으로 저조한 혐기성 처리효율과 탈수능을 나타내고 있으며, 이러한 문제점을 해결하기 위하여 많은 전처리공정들이 개발되거나 연구되어 왔다. 본 연구에서는 폐활성슬러지의 혐기성 소화효율과 탈수능을 향상시키기 위한 pulse power 전처리 연구를 pilot 규모로 수행하였다. Pilot plant는 기 수행된 실험실 연구결과를 바탕으로 설계 및 운전하였다. 본 연구에서는 pulse power 전처리에 의한 슬러지 특성변화를 평가하였으며, 특히 혐기성 소화시 미생물이 사용하기 용이한 기질의 증가를 의미하는 용존성 유기물질의 증가를 주요항목으로 평가하였다. 혐기성 소화조에서 발생하는 가스발생량과 메탄함량을 측정하여 혐기성 소화능을 평가하였으며, 슬러지 탈수능은 CST 및 비저항값의 측정을 통하여 평가하였다. 또한, 슬러지 처리공정에서의 전체적인 에너지수지를 계산하여 pulse power 전처리에 의한 에너지 회수율 변화를 평가하였다.