• 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 $60{\sim}99%$.

• 상하수도학회지
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• 제22권1호
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• pp.87-92
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• 2008

Purposes of this study were to evaluate operational performance of submerged membrane bioreactor (MBR) combined with periodic chemical backwash. Five lab-scale submerged MBRs were performed in accordance with NaOH dose, backwash solution volume. While filtration resistance of MBR system without backwash (Control) was increased persistently from startup, those of four MBR systems (RUN 1-4) with chemical backwash were maintained at $(1.4{\pm}0.16){\times}10^{12}$, $(8.6{\pm}0.90){\times}10^{11}$, $(1.9{\pm}0.10){\times}10^{12}$, $(1.4{\pm}0.10){\times}10^{12}l/m$, respectively. Under chemical backwash condition of 0.0230 M, 375 mL, permeability of membrane was highest at flux of $30L/m^2/hr$. According to results from experiment that changing condition of dose and volume, it was estimated that effect of chemical dose acts more greatly than backwash solution volume. Because COD removal rates of all MBR systems with chemical backwash were more than 96%, it was proved that NaOH added to backwash solution did not affect microorganism.

• 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.

• 한국환경과학회지
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• 제1권2호
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• pp.81.2-92
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• 1992

Growing algae spread over open water surface of water hyacinth system the leaves of hyacinth prevented the passage of sunlight through the water surface. The objectives of this study were to investigate the effects of the algae growth on the effluent of water hyacinth wastewater treatment systems operated with the variation of an organic loading rate between 190 to 550 kg COD/ha.day. The effluent from the system contained algae was discharged for about 2-3 weeks from the beginning of experimental operation of water hyacinth systems. BOD and 55 concentration of effluents during algae growthing periods were higher than those during the period of algae control. But nitrogen and phosphrous romoval efficiencies during in algae growthing periods were slighty higher than those during the period of algae control.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2004년도 춘계학술발표회
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• pp.81-84
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• 2004

Control of Sediment is very important in prawn farm due to the eruption of toxic material such as W1ionized H2S, NH3 and NO2-. In this study, column test study, column with filter media such as activated carbon, zeolite, oyster shell and iron chloride to evaluate the reduction of toxicity from sediment ammonia-N(NH3) was effectively removed by Zeolite and oyster shell. It was indicated that ammonium ion(NH4+) was removed by ion exchange of zeolite. And the ammonia in the column of oyster shell was existed as the form of NH4+, which is not toxic for prawn because oyster shell was stably kept around pH 8. Therefore, some of ammonia(NH3) was reduced by oyster shell. Hydrogen sulfide and COD were effectively removed by adsorption of activated carbon and a partial removal of hydrogen sulfide was accomplished by Oyster shell. Phosphorous was removed by activated carbon, oyster shell and iron chloride. In prawn farm, the concentration of ammonia was increased with increase of pH by algae photosynthesis in the column of activated carbon, zeolite and iron chloride, but it was revealed that pH was stably kept in the column of oyster shell.

• 한국물환경학회지
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• 제20권1호
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• pp.37-41
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• 2004

This paper was studied about the characteristics of treatment by ionized gas for livestock wastewater, aiming at the effects of ionized gas on organic matter, hydrophobic and hydrophilic organic matter in livestock wastewater when the new process of advanced oxidation process was applied for meeting the improved the quality of effluent. The organic matter within treated livestock wastewater by ionized gas was partially mineralized according to the time increasement. The $TCOD_{Mn}$ in the livestock wastewater was decreased from 840mg/L to 340mg/L when treated by ionized gas by the enhancement of time. We occupied the equations of $TCOD_{Cr}$, $SCOD_{Cr}$, $TCOD_{Mn}$ and $SCOD_{Mn}$ as to ionized gas treated time. As $TCOD_{Mn}$ increasing ionized gas treated time, the concentration did not meet the water quality, $COD_{Mn}$ 4Omg/L. So, for removing of the remaining organic matter in the efflent after ionized gas, following process is necessary. After treating the livestock wastewater by ionized gas, coagulation was considerable for organic matter removal up to regulation water quality. From UV scans of the treated livestock wastewater by ionized gas, the wastewater has low aromaticity and good colour.

• 한국물환경학회지
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• 제23권5호
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• pp.756-760
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• 2007

Most of the sewage treatment plants in Korea are being operated by using the conventional activated sludge process. Recently, as the water criteria have been strict with regard to such main culprits of eutrophication, the existing sewage treatment plants are obliged to upgrade their treatment technology to meet the criteria. Under such circumstances, this study was aimed at analyzing the conditions of an existing sewage treatment plants in Korea, and thereupon, test its treatment performance for the actual sewage water by operating a pilot plant. When the pilot plant was operated with the NPR process at the capacity of $30m^3/day$, the average contents of BOD, $COD_{Mn}$, SS, T-N and T-P in the effluents were 7.0 mg/L, 9.7 mg/L, 5.1 mg/L, 8.0 mg/L and 0.23 mg/L, respectively, which were very stable in general. Accordingly, if the NPR process used for this pilot plant to upgrade the treatment technology for the sewage treatment plat could be adopted, the effluent water quality criteria effective beginning from 2008 would be met.

• 한국환경과학회지
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• 제23권6호
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• pp.1061-1066
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• 2014

This study has cross checked the change of internal sludge-recycle in Anaerobic-Digestion, and researched about not only the improvement of Bio-gas production from the digested sludge but also the efficient method of sludge minimization. Ultimate object of the study is to reduce the amount of sludge by the improved efficiency of contact with the organic-matter and the microbes in Anaerobic-Digestion. The sludge-recycle fluidized sludge layer and raised the activity of the sludge, the optimal sludge-recycle ratio, VS and COD removal ratio were 1,000%, 28.2% and 27.7%, respectively. Through these results of this study, it may be of use to treat waste sludge by the sludge-recycle ratio in terms of minimization and circulation of resources.

• Asian-Australasian Journal of Animal Sciences
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• 제6권2호
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• pp.205-209
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• 1993

A new treatment system for animal waste water has been developed as an alternative to the activated sludge process. It consists of two treatments; one is operated with 7 tanks, and the other is soil and plant cultivation bed. Aerobic microorganisms are added to the influent water in the tanks where the water is aerated so that the microbes utilize the pollutants, while sedimentation removes the indigestible solids. In the secondary treatment the water, which has already received a primary treatment, is filtered through soil where it also receives treatment by soil organisms. In addition there is transpiration of water and absorption of minerals by plants. In the primary treatment BOD, SS, coliforms (E. coli), TP and total bacteria were removed 79-99%, but COD and TN were removed only 58% and 36%, respectively. In the secondary treatment removal of nutrients proceeded further, and 93-99% of pollutants were removed. The treated waters met the quality standard of discharge water in Japan except for TN, which was in too great a concentration to meet discharge standards. This problem requires further study.

• Journal of Forest and Environmental Science
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• 제30권1호
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• pp.85-90
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• 2014

Dewaterability, one of the important properties of wastewater sludge, was investigated using a simple capillary suction time (CST) measurement method. CST and SRF have a very close co-relation. It was convinced that CST method was quite effective, and compensating the time-consuming SRF of conventional drainage measuring method. It turned out that one could use the results of CST to find optimum flocculants ratio to improve drainage in wastewater treatment for the tissue paper production at a mill. Since the optimum ratio of flocculants could be determined with the value of CST and COD removal efficiency could be improved with precise ratio of flocculants. Thus, using CST for determining the optimum ratio of flocculants could be economical by reducing the amount of flocculants. Dewaterability might be measured within several seconds using the values of CST in a precise way. The dewaterability could also be useful in investigating the optimum ratio of flocculants.