• 한국안전학회지
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• 제15권4호
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• pp.127-133
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• 2000

The incomplete treatment of the swinery wastewater is one of the major factors of the river contamination resulting from an eutrophication. Even through many treatments were considered to reduce the contamination of the river by the swinery wastewater, the most effective treatment was not developed yet. Therefore, this project was focused on the development of the treatment that was a low cost and a high efficiency using a steel-making slag. The swinery wastewater was passed through a U-type tube packing the slag in the laboratory. And the swinery wastewater was cleaned effectively in the laboratory experiment. Based on these laboratory results, the treatment facility in a stock farm was constructed to confirm the effect of slag on the first-treated swinery wastewater. After the treatment of the first-treated swinery wastewater through the slag, the water quality of the river was improved and the biodiversity was increased.

• 상하수도학회지
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• 제32권4호
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• pp.325-335
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• 2018

The annual total phosphorus load caused by public wastewater, nightsoil and livestock manure treatment facilities in Korea has been examined macroscopically. Annual domestic average phosphorus (P) inflows through the income of phosphate rock for the last five years (2012 - 2016) were analyzed as 76,598 tons/year. As of the year 2015, the total loadings of phosphorus attributed to public wastewater treatment facilities, nightsoil treatment facilities and livestock wastewater were estimated as 30,269 tons/year, 1,909 tons/year and 18,138 tons/year, respectively. Considering the amount of phosphorus imports, the annual phosphorus load from wastewater, livestock wastewater and excretions is equivalent to 39.5%, 23.7%, 2.5% and totally 65.7%(39.5% + 23.7% + 2.5%). Therefore, the introduction of phosphorus recovery and recycling processes for the public wastewater and livestock manure treatment facilities has been found to be effective because it could reduce the import amount of phosphate rock by up to 60% or more.

• 유기물자원화
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• 제20권3호
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• pp.52-59
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• 2012

처리공정별 연계처리수질을 검토한 결과 생물학적처리만 거친 생물반응조 처리수의 경우 연계부하율이 $COD_{Mn}$의 경우 1.67%(설계수질 기준), 2.59%(운영수질 기준), T-P의 경우 3.69%(설계수질 기준), 7.67%(운영수질 기준)로 다소 높게 나타났으나 하수처리장 운영에 미치는 영향은 거의 없을 것으로 판단된다. 또한, 고도처리공정인 산화부상분리 처리수 및 생물여과 처리수의 경우 연계부하율은 1% 내외로 고도처리설비 설치 시 과대 설비설치의 우려가 있다. 따라서 S하수처리장의 경제성 및 안정적인 운영을 고려할 경우 생물학적처리인 생물반응조를 거친 처리수를 연계하는 것이 바람직할 것으로 판단된다.

• 한국물환경학회지
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• 제29권1호
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• pp.127-137
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• 2013

Reuse of wastewater will intensify in the coming decades due to water shortage, the change of climatic conditions, the need for industrial and agricultural use and the necessity of improving health and environmental conditions for the growing population. This paper considers (a) the status and trends of wastewater reuse and reclamation in the world, (b) case studies of wastewater reuse projects, (c) analysis of technology level, (d) forecast of global market, and (e) the future views and directions in development of wastewater reuse technologies. Based on the available documented literature, this paper provides a review assessment of the current status of the wastewater treatment processes including potential applications for reuse. Key challenges for both wastewater treatment and reuse are also discussed in the paper and include recommendations, e.g. cost, effluent water quality, energy use and technical solutions, for future developments.

• 한국물환경학회지
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• 제22권2호
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• pp.333-341
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• 2006

The concept for the decolorization in biological dye wastewater treatment systems is based on anaerobic treatment, for the reductive cleavage of the dyes' azo linkages, in combination with aerobic treatment, for the degradation of the products from azo dye cleavage, aromatic amines. Batch tests were conducted to examine the conditions and the factors affecting biological treatment of dye wastewater. From the tests, the removal efficiencies of organics and colors of dyeing wastewater were improved to $COD_{Cr}$ 27% and color 9% by injecting 10% of the domestic wastewater as a cosubstrate, and $COD_{Cr}$ 30%, color 22% with 30% injection of domestic wastewater. Therefore it was proved that decolorization efficiency is demonstrated with domestic wastewater as a cosubstrate. The 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.

• 한국환경보건학회지
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• 제23권1호
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• pp.34-42
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• 1997

A laboratory experiments were performed to investigate the treatment of photographic processing wastewater by chemical oxidation and biological treatment system. The effect of reaction conditions such as hydrogen peroxide dosage, ferrous sulfate dosage and pH on the COD removal in Fenton oxidation were investigated. The optimal dosage of hydrogen peroxide was 2.58 M and 3.87 M for the developing and fixing process wastewater, respectively. The Fenton oxidation was most efficient in the pH range of 3-5 and the optimal condition for initial reaction pH was 5 for a developing process wastewater. With iron powder catalyst, the COD for a developing process wastewater was removed in lower pH than with ferrous sulfate catalyst. The removal efficiency of COD for refractory compounds such as Diethyleneglycol, Benzylalcohol, Hydroxylamine Sulfate, Ammonium Thiosulfate, Ammonium Ferric EDTA and Disodium EDTA in the photogaphic wastewater was found than 90% except Potassium Carbonate. When the photographic processing wastewater after pretreatment by Fenton oxidation was treated with batch activated sludge process, the addition of $KH_2PO_4$ as a phosphorous compound improved the removal efficiency of COD. During the continuous biological treatment of developing and fixing process wastewater after pretreatment by Fenton oxidation, the effluent COD concentration less than 100 mg/l was obtained at 0.425 and 0.25 kgCOD/m$^3$.d, respectively.

• 한국물환경학회지
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• 제28권5호
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• pp.639-645
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• 2012

The purpose of this study is to identify the possibility of the CMP wastewater treatment from semiconductor fabrication under operating tubular membrane with coagulants. To find suitable coagulants treating CMP wastewater, we conducted Jar-test. After Jar-test experiments suitable coagulants are PAC(17%), $Ca(OH)_2$ and optimum coagulant dosage is PAC(17%) 10mg/L, $Ca(OH)_2$ 110 ~ 120mg/L. Based on these results, the tubular membrane was applied to CMP wastewater, the turbidity removal efficiency is $Ca(OH)_2$ > PAC(17%) > Nothing. The fast cross-flow velocity and backwash process what are operating characteristics of tubular membrane can be stable CMP wastewater treatment. But when the coagulant and tubular membrane are used at the same time, the withdraw and treatment of the CMP wastewater are possibile. However further treatment process needs if treated water will be used for semiconductor fabrications.

• 한국환경보건학회지
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• 제24권1호
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• pp.62-69
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• 1998

It has been studied that the measurement of odor component emission at confectionery manufacture. The objects of this study were to investigate reduction of offensive odor. The survey effects of odorous materials are presented as follows. The countermeasure of operating process is to minimize sludge sediment in each unit facility. Especially, in summer, we have to clean the sludge frequently, because anaerobic decomposing is likely to occur easily. The sludge or scum from sedimentation tank pond, and floating tank should be treated quickly. We should avoid overloading operation. In the case of overloading, dissolved oxygen should be increased, the quality of wastewater input should be decreased. When dried cakes from condense tank or floating tank are left in treatment plant, we should cover, to prevent diffusion of smell with masking materials. The seasonal condition of operating should be fixed and the kind of coagulants should be changed because the wastewater in each season have different loading rates and organic materials. Odorous materials are very sensitive to the seasonal temperature variation. Especially, when the amount of rainfall is small and the high temperature of maintenance in long periods, air diffusion rate is large, so odorous materials can make great effect on surroundings comparision with other periods. To reduce odorous gas, as short term method, we had better take ceramic addition method. Especially, in summer we should take ceramic addition method. Also, as long term method, the size of wastewater treatment facility is the most important in the normal operating of wastewater treatment facility. But wastewater treatment facilities in this factory are too old, treatment process is old fashion, and the size is too small. So, large wastewater quantity to treat in summer. As results, the expansion of wastewater treatment facility and the process of improvement are required. Restriction level of odor was exceed. As it is overloaded in summer, the basis cause of odor is that the size of wastewater treatment facility is small. The prediction of air quality equilibrium density variation show that the odorous materials from working place are Amine materials whose smell strength is about 2.5(a little strong degree). We can suppose that in summer is sensitive to temperature variation, smell strength is larger as to reduce the origin of odor. We must expand wastewater treatment facility and improve the process A.S.A.P.

• 상하수도학회지
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• 제31권4호
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• pp.289-296
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• 2017

Pulp and paper industry produces large volumes of wastewater and residual sludge waste, resulting in many issues in relation to wastewater treatment and sludge disposal. Contaminants in pulp and paper wastewater include effluent solids, sediments, chemical oxygen demand (COD), and biological oxygen demand (BOD), which should be treated by wastewater treatment processes such as coagulation and biological treatment. However, few works have been attempted to predict the treatment efficiency of pulp and paper wastewater. Accordingly, this study presented empirical models based on experimental data in laboratory-scale coagulation tests and compared them with statistical models such as artificial neural network (ANN). Results showed that the water quality parameters such as turbidity, suspended solids, COD, and UVA can be predicted using either linear or expoential regression models. Nevertheless, the accuracies for turbidity and UVA predictions were relatively lower than those for SS and COD. On the other hand, ANN showed higher accuracies than the emprical models for all water parameters. However, it seems that two kinds of models should be used together to provide more accurate information on the treatment efficiency of pulp and paper wastewater.

• 해양환경안전학회지
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• 제2권1호
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• pp.67-75
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• 1996

An innovative batch electrolytic system consisted of electrolytic basin, which was equipped with DSA(Dimensionally Stable Anode) type insoluble electrode, Ti/IrO2 anode and H-C metal cathode, and flotation separator was developed for the efficient treatment of shipboard emulsified oily wastewater. The electorod cleance and current density of elecrolytic basin to ensure maximum treatment efficiency of oily wastewater was evaluated as 6 mm, 3 A/dm3, respectively. The electrolytic efficiency of oily wastewater was affected by the operationtemperature, and it means that the temperature controller to ensure the stabiity of the process is required. The conductivity in the electrolytic basin was increased with the percentage of sea water in the oily wastewater, and over 90% of treatment efficiency of oily wastewater could be obtained at 7% of sea water. The oil removal rate was increased according to the increase of the quantity of electricity, and the maximum value of electrilyic rate constant was 288 mgoil/A.min. The information obtained from this study might be used for development of an efficient continuous electrolytic system treating the emulsified oily wastewater.