• Journal of the Korea Academia-Industrial cooperation Society
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• 제13권2호
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• pp.941-946
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• 2012

Macrophyte plays an important role in purification of wastewater. They have capacity to improve the water quality by absorbing nutrients, with their effective root system. In this study, removal of nutrient as well as organic matter was observed by some important macrophytes i.e. Pistia stratoites, Hydrocharis dubia and Salvinia sp. indepe ndently as well as in mixed culture under the laboratory condition. The highest total nitrogen removal was observed for Pistia stratoites (86.47%) in monoculture and Salvinia sp. + P. stratoites (76.11%) in mixed culture system. Corresponding figures for total phosphorous were observed for P. stratoites (75.60%) in monoculture and Salvinia sp. + P. stratoites (71.11%) in mixed culture system. Similar result was observed for ammonia removal in both systems. Additionally, P. stratoites showed the highest removal of organic matter, in monoculture system (68.46%) where as Salvinia sp. + P. stratoites showed the highest removal of organic matter in mixed culture system (82.73 %).

• Environmental Engineering Research
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• 제23권2호
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• pp.210-215
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• 2018

Coal seam gas (CSG) water, to be discharged, has been usually treated in reverse osmosis (RO) plants which require extensive and expensive pre-treatment. However, current low gas prices have been a great driver for relevant industries to seek for alternative cost-effective technologies in the aspect of its beneficial use and fit-for-purpose usable water production. In this paper, a combined system with a two-stage pore control fiber (PCF) filtration and a RO system was designed and tested for CSG water treatment. Also, a coagulation reactor was placed in front of the PCF to further enhance suspended solid removal. More than 99% of SS were removed through the PCF filtration while organic, total nitrogen and total phosphorous were mostly removed by the RO system. Especially along with a decrease in conductivity, the total dissolved solid derived from salts was mainly removed in the RO system. Having $OH^-$ undetected, $HCO_3{^-}$ was found to be a dominant compound and its removal efficiency was 97-98% after the RO treatment. And a Fe(III) type of Polytetsu, which was the first to be tested in this paper, was found to be a better option than a Al(III) type of Poly Aluminium Chloride due to its greater coagulation efficiency and applicability at a broader range of pH than the Al(III) type. In addition, there was no noticeable change in oxidation reduction potential, suggesting that an additional process is required to oxidize non-ionic organic carbons (detected as total organic carbon).

• Korean Journal of Soil Science and Fertilizer
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• 제28권3호
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• pp.241-248
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• 1995

This experiment was conducted to obtain basic information for the management of soil and fertilization for plastic-house soil cultivated Khwari green pepper in Dang Jin area of Chung Nam Province. The range of pH with highest frequency for 36 sites investigated was 6.1~6.5, OM 1.6~2.5%, available phosphorous 601~800mg/kg, CEC 12.1~14.0 c mol/kg, clay 16.1~18.0% and below 2.0ds/m for electical conductivity of soil. Fesh fruit weight of green pepper showed very high significant positive correlation with organic matter, clay content and cation exchange capacity, while negaive correlation with electrical conductivity. Electrical conductivity showed highly significant negative correlation with CEC, clay content and organic matter in soil, respectively. To decrease below 2.0 dS/m of electrical conductivity in plastic-house soil, the content of clay and organic matter could be maintained at above 1.8% and 2.3%, respectively.

• Journal of Environmental Science International
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• 제28권11호
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• pp.983-991
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• 2019

This study investigated the use of a hydroxyl-radicals-generated microbubble/catalyst (MB/Cat) system for removing organic pollutants, nitrogen, and phosphorous from liquid fertilizer produced by livestock wastewater treatment. Use of the MB/Cat system aims to improve the quality of liquid fertilizer by removing pollutants originally found in the wastewater. In addition, a reduction effect has been reported for antibiotics classified as representative non-biodegradable matter. Samples of liquid fertilizer produced by an aerobic biological reactor for swine wastewater treatment were first analyzed for initial concentrations of pollutants and antibiotics. When the MB/Cat system was applied to the liquid fertilizer, TCOD, TOC, $BOD_5$, and $NH_3-N$, and $PO_4-P$ removal efficiencies were found to be approximately 52%, 51%, 30%, 21%, and 66%, respectively. Additionally, Amoxicillin hydrate was removed by 10%, and Chlortetracycline HCl and Florfenicol were not present at detectable levels These findings confirm that the MB/Cat system can be used with livestock wastewater treatment to improve liquid fertilizer quality and to process wastewater that is safe for agricultural re-use.

• Korean Journal of Soil Science and Fertilizer
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• 제35권3호
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• pp.175-184
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• 2002

Soil chemical parameters of peach orchards and the concentration of nutrients in peach leaves were investigated. Results of soil analysis showed that pH value and content of exchangeable calcium was quite low, required to adjust soil acidity in many investigated soils. Nitrogen and phosphorous contents in leaves were founded to be excessive comparing to RDA's optimal levels(N $29.3{\sim}35.9g\;kg^{-1}$, P $1.7{\sim}2.2g\;kg^{-1}$), while calcium contents were lower than optimal levels($11.2{\sim}21.0g\;kg^{-1}$) in many sites and Potassium content was higher in peach cultivars than nectarine cultivars. Correlation analysis revealed that organic matter contents in subsoils and exchangeable calcium content in soils(top and subsoil) were increased with cultivation year, but available phosphate contents in subsoils were decreased. Organic matter and exchangeable magnesium contents in top soils were positively correlated with potassium and magnesium contents in leaves, whereas were negatively correlated with calcium contents in leaves, impling antagonistic absorption of calcium against potassium and magnesium. The findings indicated that most of soils ought to managed to adjust soil acidity and application amount of nitrogen, phosphorous fertilizer and compost should be controlled properly.

• KSBB Journal
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• 제22권2호
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• pp.102-108
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• 2007

A sewage was treated using a vertical flow zeolite-filled reed bed. The sewage from the student dormitory of Changwon National University was fed into the reed bed for 10 minutes every 6 hours at the hydraulic load of $314L/m^3{\cdot}$day. The filtering height of the reed bed was 100 em and the zeolite mixture was filled in the reed bed. The mixture consisted of the same volume of two types of zeolite: 0.5$\sim$1 mm and 1$\sim$3 mm in diameter. Annual average removal efficiency was 88 89.9%, $COD_{Cr}$ 86.1 %, $COD_{Mn}$ 81.2%, T-N 34.0%, $NH_4^+$-N 97.3% and T-P 34.6%. T-N of effluent was mostly $NO_3^-$-N and the concentration of $NO_2^-$-N in effluent was lower than 0.1 mg/L. All removal efficiencies did not show a remarkable seasonal change. The ranking of phosphorous fractions fixed to the zeolite in column test was Ca-P > Fe-P > reductant soluble Fe-P > occluded P > saloid P > AI-P at all depths of the filter. All phosphorous fractions except for AI-P reduced at deeper filter layer, while their content ratios increased at deeper filter layer. Organic matter content was the highest at the highest layer (0$\sim$5 cm from the top of the filter) and only small differences were observed at the deeper filter layer than 5 em from the top. Organic matter content increased at all depths of the filter with the operating time.

• Journal of Wetlands Research
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• 제14권2호
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• pp.265-275
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• 2012

As climate change is becoming a growing concern and the importance of water management is increasing, the retention of carbon and nutrients in wetland soils including inland and coastal area has become important. In this study, retention characteristics of organic matter and nutrients of coastal sediment and soils in different types of wetlands such as constructed wetland, natural (inland marsh, estuary, tidal flat) wetlands were investigated. A correlation analysis was also performed to understand the relationship among organic matter properties, nutrient concentrations and soil texture of wetland soils. The degree of retention of organic matter and nitrogen in wetland soils varied with the wetland type. Inland wetlands retain more nitrogen than estuary or coastal wetlands, and natural wetlands retain more organic matter and nitrogen than constructed ones. Coastal sediments in a bay area where seawater circulation is restricted have more nutrients than those in estuary or tidal flats where seawater circulates well. The results showed that the sediment chemical oxygen demand has a high correlation with the total organic carbon and the total nitrogen in the studied area.

• Clean Technology
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• 제28권1호
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• pp.63-78
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• 2022

Electronics industrial wastewater treatment facilities release organic wastewaters containing high concentrations of organic pollutants and more than 20 toxic non-biodegradable pollutants. One of the major challenges of the fourth industrial revolution era for the electronics industry is how to treat electronics industrial wastewater efficiently. Therefore, it is necessary to develop an electronics industrial wastewater modeling technique that can evaluate the removal efficiency of organic pollutants, such as chemical oxygen demand (COD), total nitrogen (TN), total phosphorous (TP), and tetramethylammonium hydroxide (TMAH), by digital twinning an electronics industrial organic wastewater treatment facility in a cyber physical system (CPS). In this study, an electronics industrial wastewater activated sludge model (e-ASM) was developed based on the theoretical reaction rates for the removal mechanisms of electronics industrial wastewater considering the growth and decay of micro-organisms. The developed e-ASM can model complex biological removal mechanisms, such as the inhibition of nitrification micro-organisms by non-biodegradable organic pollutants including TMAH, as well as the oxidation, nitrification, and denitrification processes. The proposed e-ASM can be implemented as a Water Digital Twin for real electronics industrial wastewater treatment systems and be utilized for process modeling, effluent quality prediction, process selection, and design efficiency across varying influent characteristics on a CPS.

• Korean Journal of Soil Science and Fertilizer
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• 제15권3호
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• pp.199-206
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• 1982

A field experiment was conducted to compare the effects of compost and rice straw application on the growth of soybean, chemical properties and soil microorganism in newly reclaimed silty clay loamy upland soil. Application rates of the arganic materials were 750 Kg, 1,500 Kg and 3,000 Kg/10a in compost, and 340 Kg, 680 Kg and 1,360 Kg/10a in rice straw. The differences of N.P.K. application rates caused by the two different organic materials were balanced by chemical fertilizers of N.P.K. The results can be summarized as follows; 1. The yield of soybean was increased upon compost application, but no significant difference on yield was observed except luxuriant plant growth upon rice straw application. 2. There was highly possitive correlation between concentration of phosphorous, potassium in soybean plant at 71 days after planting and dry weight of grain vs. stem plus bean chaff of harvest plant in compost applied plots, but no correlation was found in rice straw applied plots. 3. In greneral, the soil water contents in organic material applied plots, expecially in plots of rice straw, were higher than in no organic material plots. However, at wilting point, the soil water content in organic material applied plot was lower compare to no organic material plot. 4. The weight of nodules per soybean plant was heavier notwithstanding the fewer number of soil bacteria and fungi in compost application plots than rice straw application plots.

• Journal of the Korean Society of Environmental Restoration Technology
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• 제8권6호
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• pp.59-68
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• 2005

This study was carried out to investigate soil properties, ordination, and vegetation of the coastal sand dune in Sinduri, Taean-Gun. 1. The Orobanche coerulescens and Ixeris repens that are a peculiar species were found in Sinduri coastal sand dune and the Salix purpurea var. japonica that is an endemic species of korea was found in that place. The plant communities was categorized into seven groups, such as Rosa rugosa community, Vitex rotundifolia communit, Carex kobomugi community, Imperata cylndrica var. koenigii community, Carex pumila community, Artemisia capillaris community, and Calamagrostis epigeios community. 2. The soil organic matter, total nitrogen, available phosphorous concentrations, and cation exchange capacity were lower in the study sites than in forest soil of seashore. There was little difference in soil exchangeable Ca, Mg, and K concentrations between in the study site and in the forest soil of seashore. The soil pH was ranged from 5.69 to 7.63. The soil texture in the study site was sand or loamy sand. 3. The results of the correlation between Sinduri coastal sand dune community and environmental factor are as follows; the soil pH was the most effect to the community distribution, and CEC, total nitrogen, soil organic matter, and the amount of silt in soil have some correlation with community distribution. 4. The results of the correlation between Sinduri coastal sand dune community and soil characteristics are as follows; the Calamagrostis epigeios community was found in area that have high soil moisture content; the Rosa rugosa community was found in area that have high soil CEC, organic matter concentration, and total nitrogen concentration, and low soil pH; the Vitex rotundifolia community, Carex kobomugi community, and Artemisia capillaris community were found in area that have low soil CEC, organic matter concentration, and total nitrogen concentration, and high soil pH; the Imperata cylndrica var. koenigii community and Carex pumila community were found in area that have medium soil CEC, organic matter concentration, total nitrogen concentration, and soil pH.