• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.8
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• pp.367-377
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• 2017

This study examined the effects of the salinity of seafood wastewater on the sulfur denitrification process. An examination of the denitrification efficiency showed that the optimal EBCT was 1hr at an influent T-N concentration of 20mg/L or lower and 2-3hr at an T-N concentration of 30mg/L. An examination of the denitrification efficiency according to the nitrogen load showed that the legal effluent water quality criterion was satisfied when the influent load was maintained within $0.496kg/m^3/day$. On the other hand, the reactor volume increased when this was applied to the site. Therefore, the influent load should be within $0.372kg/m^3/day$ considering the denitrification and economic efficiency. At a load of $0.248{\sim}0.628kg/m^3{\cdot}day$, the k value was $0.0890{\sim}0.5032hr^{-1}$. The batch experimental results according to the $Cl^-$ concentration showed that at an influent nitrogen concentration of 30.0mg/L, the effect of the denitrification efficiency was not large below the salinity of $7,000mgCl^-/L$, but inhibition occurred above $9,000mgCl^-/L$. Calculations of the reaction rate constant according to the $Cl^-$ concentration showed that the reaction rate constant was $0.1049{\sim}0.2324hr^{-1}$ at a raw wastewater concentration of ${\sim}5,000mgCl^-/L$. In contrast, the k value was $0.1588hr^{-1}$ at $7,000mgCl^-/L$ and $0.1049hr^{-1}$ at $9,000mgCl^-/L$.

• Journal of Microbiology and Biotechnology
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• v.6 no.2
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• pp.116-119
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• 1996

The biological treatment by a mixed culture GE2 immobilized on activated carbon was investigated with a phenolic resin industrial wastewater containing 41,000 mg/l of phenol and 2,800 mg/l of formaldehyde. At a dilution of 20 times with aerated tap water, influent and effluent $COD_{Mn}$ were 4,587 mg/l and 46 mg/l, that is, $COD_{Mn}$ removal efficiency was 99.0%. At this time, phenol and formaldehyde con-centration of the effluent were 1.24 and 6.80 mg/l, indicating removal efficiencies of 99.9 and 94.1%, respectively.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.6
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• pp.735-741
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• 2009

This study intends to evaluate the efficiency of non-point source reduction technique by using the porous lightweight and recycled aggregate which microorganism is seeded. In case of infiltration velocity 30~70 mm/hr in high concentration of influent, it is indicated that SS was 40~94%, COD 44~91%, BOD 4~91%, TN 1.2~66%, TP 7~70% of removal efficiency. Removal efficiency is good in infiltration velocity 30 > 50 > 70㎜/hr order. Therefore, the non-point source treatment facility filled with lightweight and recycled aggregate using microbial seeding shows higher removal efficiency than a conventional sand and gravel. We confirm that the function and efficiency are improved significantly and applied to treat non-point sources.

• Journal of Environmental Science International
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• v.10 no.4
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• pp.281-286
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• 2001

Wastewater from the pigment industry has high levels of organics and is known as hardly biodegradable. The objective of this study is to evaluate the applicability of aerobic fixed-bed boifilm reactor packed with ceramic support carrier for the pigment wastewater treatment. Orange 2(widely used azo pigment) adsorption experiment onto biofilm and activated sludge, and continuous treatment experiments were performed. In batch adsorption experiment, maximum adsorption quantity of biofilm was at least two times higher than that of activated sludge. In continuous experiment using aerobic fixed-bed biodilm reactor, the influent concentration of COD and Orange 2 were 75~500mg/${\ell}$(0.45~3.00kg COD/$m^3.day), 5~50mg/$\ell$(0.03~0.30kg Orange 2/$m^3$.day), respectively. At a COD loading rate 2.5kg COD/$m^3$.day and Orange 2 loading rate of 0.18kg Orange 2/$m^3$.day, removal efficiency of COD and Orange 2 were over 95%, 97%, respectively.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.5
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• pp.673-679
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• 2004

Particle breakthrough can occur by either the breakoff of previously captured particles (or flocs) or the direct passage of some influent particles through the filter. Filtration experiments were performed in a laboratory-scale filter using spherical glass beads with a diameter of 0.55 mm as collectors. A single type of particle suspension (Min-U-Sil 5, nearly pure $SiO_2$) and three different destabilization methods (pH control, alum and polymer destabilization) were utilized. The operating conditions were similar to those of standard media filtration practice: a filtration velocity of 5 m/h. To assess the possibility of particle detachment during the normal filtration, a hydraulic shock load (20% increase of flow rate) was applied after 4 hours of normal filtration. The magnitude of particle detachment was proportional to the particle size for non-Brownian particles. At the same time, less favorable particles, i.e., particles with larger surface charge, were easily detached during the hydraulic shock load. Therefore, proper particle destabilization before filtration is crucial for maximum particle removal as well as minimum particle breakthrough.

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.06a
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• pp.197-201
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• 2004

This study was to determine the prevalence of Legionella species in public spas and to know that the presence of Legionella was correlated with other microbiological parameters. A total of 81 water samples were collected from 30 different public spas and sudatoriums so called zzimzilbang in Korea. Although Legionella was not detected in the influent water and the cold tub water, of the 38 samples of hot and warm water taken from public tubs, 11(28.8%) were found to be positive for Legionella spp. All of the isolates were identified as a species L. pneumophila serogroups 1 and 2-14 by latex agglutination. And HPC concentrations in all spas water isolated Legionella were above the level of $10^4\;cfu/ml$.

• KSBB Journal
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• v.16 no.3
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• pp.314-319
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• 2001

A nitrifier consortium immobilized in polyvinyl alcohol was used to remove ammonia nitrogen from synthetic wastewater in an airlift bioreactor. The minimum aeration rates were 0.4, 0.6, 0.8 and 1.0 vvm for 5, 10, 15 and 20% immobilized bead packing volume fraction, respectively. The efficient packing fraction and the aeration rate for ammonia nitrogen removal were 15% and 2.4 vvm, respectively. With a hydraulic retention time of 0.5hr, the removal rate and the efficiency of ammonia nitrogen removal were 1685 g/㎥$.$day and 48% at an influent ammonia nitrogen concentration of 75 g/㎥.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.542-547
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• 2000

It has become interested in the concept of permeable barriers for the containment and/or destruction of contaminated groundwater. The purpose of these trench-like barriers is to provide in situ capture and possibly destruction of the contaminant while preserving groundwater flow to uncontaminated zones. For instance, a trichloreethylene(TCE) plume may be contained by a permeable in which reactive iron reduces TCE to ethylene and ethane, compounds which can be easily biodegraded. The objective of this research is to examine the feasibility of using zero-valent iron as a clean-up media in permeable reactive barrier system. A series of laboratory column tests are performed. The concentration of influent and effluent water and the rate of clean up are analysed from these test results. The experimental result shows that the majority of the contamination in groundwater is removed in the reactor. And it shows the corresponding increase in the concentration of chloride ions through the reactor. Results from this study indicate that permeable reactive barrier containing admixtures of zero-valent iron and other materials can effectively clean up groundwater contaminated with organic compounds.

• Journal of Environmental Science International
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• v.17 no.4
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• pp.405-412
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• 2008

Statistical analysis technique was applied to operating parameters and removal efficiency data sets obtained from advanced wastewater treatment plant during 1 year. Through factor analysis three factors derived varimax rotation were selected each plant. Three components explained 96%, 87% of the total variance of the process, respectively. The components on $A_2O$ Plant were identified in the following order : 1) Shortening the SRT during high-flow period, 2) Keeping biomass high on winter 3) factor was related to DO. On DNR plant, we defined them as follows: factor 1, Prolonged the SRT during high-flow period; factor 2 was related to sludge return; factor 3, Influent BOD during low-DO period. This technique was believed to assist operators in identifying priorities to improve operation efficiency.

• Journal of Environmental Health Sciences
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• v.27 no.1
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• pp.1-7
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• 2001

Ammonia is used in the manufacture of fertilizers, refrigerants, stabilizers and many household cleaning agents. These wide applications resulted in ammonia contamination in water. Ammonia can be removed from water by physical, biological, and chemical methods. Ozonation is effictive in the treatment of water with low concentration of ammonia. This study is undertaken to provide kinetic data for the ozonation of ammonia with or without hydrogen peroxide. The results were as follows; The destruction rate of ammonia increased gradually with the influent hydrogen peroxide concentration up to 0.23 mM and inhibited in the range of 0.23~11.4mM, and the maximum removal rate of ammonia achieved at 0.23mM of hydrogen peroxide, and the overall kinetics was first order. The combination effect of hydrogen and ozone to oxide ammonia in aqueous solution was better than ozone alone. The reacted ammonia was converted completely to nitrate ion.