• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.1 no.1
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• pp.11-17
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• 1997

The treatment performances of anaerobic-aerobic activated sludge process were investigated under various operation conditions. The treatment system proposed in this study gave a relatively stable performance against hourly change of the flow rate and showed a satisfactory removal efficiency of nitrogen and phosphorus compounds under experimental conditions. The average removal efficiency of total nitrogen gradually decreased as the influent total nitrogen concentration was increased. High C/N ratio of the wastewater was required for the complete removal of nitrogen. Glucose as a carbon source was more efficient than starch and the removal ability for all components become higher with the increase of the fraction of glucose.

• Journal of Environmental Science International
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• v.1 no.1
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• pp.11-17
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• 1992

The treatment performances of anaerobic-aerobic activated sludge Process were investigated under various operation conditions. The treatment system proposed in this study gave a relatively stable performance against hourly change of the flow rate and showed a satisfactory removal efficiency of nitrogen and phosphorus compounds under experimental conditions. The average removal efficiency of total nitrogen gradually decreased as the influent total nitrogen concentration was increased. High C/N ratio of the wastewater was required for the complete removal of nitrogen. Glucose as a carbon source was more efficient than starch and the removal ability for all components become hither with the increase of the fraction of glucose.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.4
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• pp.493-500
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• 2023

The use of TiO₂ photocatalyst in the production of concrete blocks for the purpose of nitrogen oxide reduction is an issue of controversy due to the conflicting evidence on its effectiveness. Efforts have been made to reduce the level of nitrogen oxides in the environment by using of titanium dioxide (TiO₂). This study examined the effect of incorporating activated carbon into concrete blocks on the reduction of nitrogen oxides released into the atmosphere and the durability of the blocks. The efficiency of photocatalyst was enhanced through the addition of a surrounding conductive substance. The addition of activated carbon resulted in a significant increase in the electrical conductivity of photocatalytic blocks and improved durability. The cement mixture using 5 % TiO₂ and 15 % activated carbon exhibited the optimal mixing ratio for the purpose of nitrogen oxide removal. The effect of the addition of conductive carbon to the photocatalytic blocks was discussed with the results of conductivity, flexural and comprssive strength and nitrogen oxide removal test. The relationship between the addition of conductive carbon to the photocatalytic blocks and its resulting effects have been studied by several tests, including conductivity, flexural and compressive strength, and nitrogen oxide removal.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.10a
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• pp.209.1-209
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• 1978

Treatment of domestic sewage discharged from big cafeteria kitchen, especially rice-washing water, was examined by the use of activated sludge process and phytoplankton cultivation. Only with a activated sludge process COD value decreased from around 1000 mg/ι to 100 mg/ι, but nutrients, such as nitrogen and phosphate could not be removed sufficiently phytoplankton cultivation in combination with a activate sludge process could decrease COD value down to 50 mg/ι and nutrients values were also reduced substantially. However, the initial concentration of 20 mg/ι in the rice-washing water could not be removed completely without addition of activated sludge as a nitrogen source.

• KSBB Journal
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• v.16 no.2
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• pp.133-139
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• 2001

To treat piggery wastewaters containing refractory compounds including nitrogen, biological treatments were investigated. In biological treatment, the removal efficiencies of organics and nitrogen by the activated sludge process and bioreactor using a BACC (Biological Activated Carbon Cartridge) media filled with granular activated carbon were examined. The results were as follows; in the biological process, when the approximate influent BOD concentration of 620 mg/L, through dilution, was treated by the activated sludge process, the process should be operated at a HRT of over 8 days to maintain an effluent BOD concentration of lower than 100 mg/L. In the treatment of piggery wastewater using a BACC bioreactor, when the HRT was 200 hours, the BOD, COD(sub)cr, and TKN removal efficiency of the effluent were 94, 75 and 64.3%, respectively. Comparing the BACC bioreactor with the activated sludge process, when the volumetric loading rate was 0.3 g BOD/L.day, the specific substrate removal rate of BOD was 0.14 g BOD removed/L.day in the activated sludge process which compared with 0.27 g BOD removed/L$.$day in the BACC bioreactor. The BACC bioreactor showed on average a 2-fold higher removal rate and was superior to the activated sludge process in wastewater treatment in terms of variations of loading time and high loading time. Therefore, the BACC process can effectively treat piggery wastewater containing high concentrations of nitrogen and organic compounds.

• KSBB Journal
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• v.16 no.2
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• pp.140-145
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• 2001

To treat piggery wastewater containing refractory compounds including nitrogen, physical treatments using zeolite and biological processes were investigated. In biogical treatment, the removal efficiencies of organics and nitrogen in bioreador using BACC (Biological Activated Carbon Cartridge) media filled with granule activated carbon were examined. The best removal efficiencies achieved for TKN and COD(sub)cr were 82% and 53% respectively, when zeolite dosage was 300 g/L. Specific nitrogen removal ability was 3.2 mg/g at a zeolite dosage of 50 g/L, whereas specific nitrogen removal ability was 1.8 mg/g at a zeolite dosage of 300 g/L. The increased of C/N ratio resulting from the removal of nitrogen using zeolite led to an increase in removal efficiency of organics. As C/N ratio was increased to 2.0, 2.44 and 6.58 at a HRT of 48 hours in a BACC bioreactor, removal efficiencies of COD(sub)cr were increased to 53.5%, 57.4% and 80.6%. The removal efficiency of wastewater using a zeolite dosage of 399 g/L was increased by 27.1% compared to that of control treatment.

• Journal of the Korean Vacuum Society
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• v.2 no.4
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• pp.491-500
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• 1993

The adsorption of nitrogen (77K) and carbon dioxide(273K) was performed on a series of activated carbon fiber. Theadsorption iotherm of nitrogen was typical type 1 and that of carbon dioxide was convex. As the specific surface area increases, there are linear increases in BET constant C mean pore diameter, the width of pore size distribution, wide micropore volume, total micropore volume, total pore volume and external surface area, however, narrow micropore volume was nealy constant . The total micorpore volume fraction in total pore volume is above 97%.

• Journal of Korean Society on Water Environment
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• v.28 no.3
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• pp.479-482
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• 2012

Membrane process has been one of the widely applied wastewater treatment options, especially in field. However, one of the tricky issues in the process is to treat concentrates generated from reverse osmosis (RO) system in a manner of saving cost with maximum efficiency for treating a wide range of contaminants. Stimulated with the challenging issues, we have conducted a series of experimental studies in the evaluation for removing organics and nutrients using activated carbon. Results indicated that while powdered activated carbon (PAC) efficiently removed organics and the extent of removal was proportional to the PAC dosage, little removal of nitrogen and phosphorus was observed despite increasing the PAC dose. Interestingly, applying PAC was superior in removing organics than using granular activated carbon (GAC). These results suggest smaller particle size with higher surface area could provide greater chemical reactivity in removing organics.

• Journal of the Korean Vacuum Society
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• v.12 no.1
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• pp.70-77
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• 2003

It is well Down that the growth of carbon nanotubes (CNTs) by chemical vapor deposition (CVD) using a transition metal catalyst is greatly enhanced in a nitrogen environment. We show here that the enhanced growth is closely related to the activated nitrogen and it's incorporation into the CNT wall and cap during growth. This behavior is consistent with theoretical calculations of CNx thin films, showing that nitrogen incorporation to the graphitic basal plane reduces the elastic strain energy for curving the graphitic layer. Enhanced CNT growth by nitrogen incorporation is thus due to a decrease in the activation energies required for nucleation and growth of the tubular graphitic layer.

• Journal of Environmental Science International
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• v.14 no.7
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• pp.675-681
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• 2005

A laboratory experiment was performed to investigate phosphorus and nitrogen removal from synthetic wastewater by intermittently aerated activated sludge process packed with aluminum and silver plate. Three continuous experi­mental processes, i. e. an intermittently aerated activated sludge process(Run A), an intermittently aerated activated sludge process with an aluminum and silver plate packed into the reactor(Run B), and a reactor post stage(Run C) were compared. In the batch experiments, the phosphorus removal time in the reactor packed with aluminum and silver plate simultaneously was faster than that of the reactor packed with only an aluminum plate. More phos­phorus was removed with an increase of NaCl concentration. The pitting corrosion of aluminum does not affect the performance of the biological treatment. The total nitrogen removal efficiency in Run B was $57\%\;and\;43.6\%$ at the HRT of 12 and 6 hours respectively. The effluent $PO_{4-}P$ concentration as low as 1.0 mg/L could be ob­tainable through the continuous experiment in Run B at HRT of 6 hours.