• Korean Journal of Environmental Biology
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• v.17 no.1
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• pp.117-124
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• 1999

Nutrients removal by water hyacinth, Eichhornia crassipes (Mart.) Solms from nutrient enriched waters and swinery wastewater were evaluated. The contents of nitrogen and phosphorus of dried water hyacinth increased from 1.4 to 3.3% and 0.21 to 0.80% when water hyacinth available N and P in the culture medium were increased from 0.7 to 5.0 mgN/1 and 0.06 o 1.5 mgP/l. respectively. Maximum N and P contents were found to be 4.1 and 0.90%, respectively. The significant relationship was observed between the standing crop of water hyacinth and the biomass yield per unit area and time. Biomass yield increased gradually until standing crop reached 15 kg wet wt./m$^2$, and then rapidly decreased. The high biomass yield of up to 0.5 kg/m$^2$/day was obtained in the range of 7 to 20 kg/m$^2$of standing crop. The potential removal rates of N and P by the water hyacinth during summer were found to be 2,250 to 2,710 mgN/m$^2$/day and 570 to 595 mgP/m$^2$/day, respectively, when 15 kg/m$^2$in standing crop and nutrient concentrations of culture medium were ranged from 1.24 to 6.2 mgP/1 and 3.2 to 32.5 mgN/1, respectively, Inorganic N and P concentrations of swinery wastewater were in the range of 82 to 121 mgN/1 and 22 to 79 mgP/1, respectively. Nitrogen and P removal rates of water hyacinth cultured in swinery wastewater were found to be in the ranges of 2,000 to 2,600 mgN/m$^2$/day and 157 to 254 mgP/m$^2$/day, respectively, at 10 times diluted water of swinery wastewater.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.443-453
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• 2012

The objectives of this study were to find out proper potting medium and nutrient levels in the soil to promote the root nodule formation in black locust (Robinia pseudoacacia L.) seedlings. Commercial potting medium, compost, organic fertilizer, molded forest fertilizer, and compound fertilizer were used at different mixing rates to bring in various levels of mineral nutrients in the soil. Seedlings were grown in pots in a greenhouse for three months. Commercial potting medium containing peatmoss, vermiculite, and geolite was not suited for early nodule formation due to lack of nutrients, even though it produced good total dry weight. Compost was the best medium to promote both high total dry weight production and nodule formation with providing the proper levels of nitrogen and phosphorus in the soil. Molded forest fertilizer was acceptable for nodule formation. Compound fertilizer and organic fertilizer was not suited for nodule formation. The potting medium should contain optimum levels of nitrogen (0.05-0.2%) and phosphorus (100-600ppm) to promote early nodule formation in black locust seedlings.

• Applied Biological Chemistry
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• v.43 no.2
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• pp.124-129
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• 2000

Nitrogen and P in surface runoff and eroded sediment from cropland areas can contaminate streams and lakes. Runoff losses of N and P were determined in a small field plot $(14.3{\times}24.8\;m)$ of peach orchard from March to November in 1999. Nitrogen and P were applied in the rate of 172 and 46 kg/ha using chemical fertilizer and mixed oil cake fertilizer. During the season, in 26 rainfall events, $421.5\;m^3/ha$ of runoff including 1,989 kg/ha of soil loss was collected. Concentrations of total-N, $NO_3-N$, $NH_4-N$, total-P and $PO_4-P$ in runoff samples were in the range of $4.7{\sim}171.0,\;0.1{\sim}188.0,\;0.13{\sim}3.36$, $0.58{\sim}4.99$ and $0.05{\sim}3.71\;mg/l$, respectively. Total loss of N was 16.39 kg/ha and 75% of the loss was $NO_3-N$. Total loss of P was 1.04 kg/ha, and $PO_4-P$ and sediment bound P accounted for 47 and 27% of the total loss, respectively. The losses of N and P were about 9.5 and 2.3% of the applied N and P in the plot, respectively. Although the loss of N or P would be relatively small in agricultural aspect, considering the high concentrations of N and P in runoff, loss of N and P from croplands should be controlled to reduce the eutrophication problem of stream waters.

• Journal of the Korean Society for Environmental Technology
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• v.19 no.6
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• pp.493-502
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• 2018

The purpose of this study was to develop EM media for water treatment and to remove nitrogen and phosphorus which cause water algae boom in water system. The ideal mixing ratio of raw material such as clay: zeolite: vermiculite: activated carbon for manufacturing the EM media was 10: 2.5: 0.1: 2, and the calcination temperature was $700^{\circ}C$. The comparison of the physical properties of manufactures using distilled water and EM activated liquid as the material mixture are as follows. Porosity and density of EM media were 39.98 % and $1.13kg/m^3$, adsorption efficiencies of nitrogen and phosphorus were 69.3 % and 38.9 %. In contrast, porosity and density of distilled water media were 37.80 % and $1.11kg/m^3$, and adsorption efficiencies of nitrogen and phosphorus were 62.5 % and 37.8 %. The adsorption rate of nitrogen and phosphorus in the EM media was higher than that of the distilled water made one by 6.8 % and 1.1 %, respectively. The adsorption characteristics of the media to nitrogen and phosphorus could be expressed by the Freudlich adsorption isotherm. The change of calcination time did not affect the adsorption efficiency of phosphorus and nitrogen when EM media was formed, but it was considered that it affects the strength of media. Nitrogen removal efficiency was the best record in 4 hours of calcination time and 3 hours of calcination time in phosphorus removal efficiency.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.306-313
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• 2001

The objectives of this study were to understand the physiological responses and resistance of red pine trees to ozone exposure in relation to nitrogen and phosphorus fertilization. Potted one-year-old seedlings of Pinus densiflora S. et Z. were exposed in an open-top chamber(OTC) to ozone at concentration of 0.12ppm for 3 hours daily for eight weeks with or without N and P fertilization alone or in combination. The OTC had dimensions of 2.0m in height and 2.5m in diameter, and the air in a control chamber was filtered with activated charcoal to maintain the ozone concentration below 0.02ppm. After eight weeks of ozone exposure, none of the seedlings showed any symptoms of visible injury on leaves. The seedlings fertilized with N and P in a control chamber showed 22 to 95% increase in total dry weight, and similar fertilizer effect was also noticed in an ozone chamber. Ozone treatment did not decrease the total dry weight, but increased shoot/root ratio by 14.5%. Ozone treatment increased sucrose content in the leaves by 23%, but decreased sucrose content in roots by 20% regardless of N or P application. Starch content in the leaves was not affected by either ozone or fertilizer. However, starch content in the roots was decreased by 41% by ozone treatment. Chlorophyll content in the leaves was increased by 70% by N application, but was not affected by ozone treatment. Nitrogen and P fertilization stimulated net photosynthesis by 80% in a control chamber, but stimulatory effect of N and P on net photosynthesis was 22.3% less in an ozone chamber. Net photosynthesis of the seedlings with no fertilization was not affected by ozone treatment. Based on the observed interactions between N, P, and ozone, it was concluded that the stimulatory effect of fertilization on growth of Pinus densiflora would be decreased by ozone treatment, but fertilization would increase resistance to ozone by re-allocation of increased carbohydrates.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4910-4916
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• 2012

Changes of low concentrated nitrogen-phosphate removal efficiency were investigated in 4 strains of marine bacteria applied to ceramic media. Marine bacteria were isolated and identified from Gwangyang bay. Growth rates and removal efficiencies of $NH_3$-N of 4 strains of marine bacteria applied to ceramic media were increased approximately 3 fold and over 30% than control group, respectively. A. hydrophila and P. diminuta had highest ${NO_3}^-$-N and phosphate removal efficiencies, respectively. This results showed that ceramic media is very nice material for improvement of nitrogen-phosphate removal efficiency and isolated marine bacteria may be useful to control nitrogen-phosphate at low concentration in field.

• Journal of Animal Environmental Science
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• v.6 no.3
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• pp.185-190
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• 2000

TAO system and solid-liquid separation (28mesh filter and 200mesh filter) were applied in processing piggery slurry to see the reduction of N and P and to draw the efficiency in reducing manure application area. The results are as follows; 1. The amount of N and P in slurry of $4.6m^3/day$ was 22.5kg/day ($4,893mg/{\ell}$) and 7.32kg/day ($1,592mg/{\ell}$). 2. Reduction rate of N and P by TAO reactor was 9.9 kg/day (46.0%) and 3.47kg/day(34.0%). 3. Reduction rate of N and P by Solid-liquid separation was 10.5kg/day (46.6%) and 5.12kg/day (69.8%). 4. One the basis of the amount of nitrogen composting, the square size of liquid manure sprinkled area was reduced from 74.6ha/y to 39.0ha/y in rice paddy, and from 63.2ha/y to 33.0ha/y by the treatment.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.730-737
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• 2010

It is very important to remove fluoride ion before treating semiconductor wastewater containing high concentration of ammonia, phosphates, and fluoride ions by struvite formation. Calcium ion was generally added for the removal of fluoride ion. However, calcium ions remained after removal of fluoride ion can deteriorate the performance of struvite crystalization. It should be removed completely before struvite formation. In this study, the effect of fluoride and calcium ion concentration on the struvite crystalization was investigated. Removal efficiencies of ortho-phosphate with struvite formation were more abruptly decreased than those of ammonium nitrogen, as increase of fluoride ion concentration in synthetic wastewater. The structures of struvite formed in synthetic wastewater containing calcium ion of up to 500 mg/L were identical. Purity of struvite was deteriorated as increase of calcium ion over 500 mg/L. Removal efficiencies of ammonium nitrogen were more decreased than those of phosphate ions as increase of cacium ion in synthetic wastewater.

• KSBB Journal
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• v.15 no.1
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• pp.14-21
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• 2000

In this study, algae cultivation using the photobioreactor has been applied to remove the nitrogen and phosphorus compounds in the wastewater of the livestock industry. The optimal ratio of nitrate and ortho-phosphate concentration was found for the enhancement of removal efficiency. To achieve the high density culture of algae, the photobioreactor consisted of optical fibers wes developed to get the sufficient light intensity. The light could be illuminated uniformly from light source to the entire reactor by the optical fibers. The structured kinetic model was proposed to describe the growth rate, consumption rate of nitrates and ortho-phosphates in algae culture. The self-organizing fuzzy logic controller incorporated with genetic algorithm was constructed to control the semi-continuous wastewater treatment system. The proposed fuzzy logic controller was applied to maintain the nitrated concentration at the given set-point with the control of wastewater feeding rate. The experimental results showed that the self-organizing fuzzy logic controller could keep the nitrate concentration and enhance algae growth.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05b
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• pp.115-118
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• 2004

축산폐수에 대한 방류수 수질기준 항목에 COD의 추가 및 질소와 인의 기준이 강화(1999년)됨에 따라 많은 축산폐수처리시설의 보강과 새로운 기술도입이 요구되고 있다. 따라서 대부분의 공공처리시설에서는 질소 및 인을 제거하기 위하여 2차 처리단계에서 무산소조(탈질조)와 호기성(포기조)를 연계한 생물학적 질소제거를 실시하고, 최종처리단계에서 응집제 투입에 의한 응집ㆍ침전공정후 모래여과 또는 활성탄 흡착공정에 의한 인과 색도제거 하는 등, 생물학적 처리 및 물리ㆍ 화학적 처리시설이 추가적으로 보완ㆍ적용단계에 있다.(중략)