• Journal of Korean Society of Environmental Engineers
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• v.34 no.5
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• pp.295-303
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• 2012

Removal of total nitrogen (T-N) and total phosphorus (T-P) was evaluated in a DEPHANOX process by adding Al(III) to the separator to maintain T-P in the final effluent below 0.2 mg/L. pH in each reactor was maintained 7~8 after addition of Al(III) to the levels of 5, 10, 15 mg/L. The removal efficiency of COD and T-N decreased at higher Al(III) dose, but T-P removal efficiency increased from 76.28 to 84.02, 94.66% at Al(III) dose of 5, 10, 15 mg/L, respectively. T-P in effluent showed 0.17 mg/L at Al(III) dose of 15 mg/L. Minimum 15 mg/L of Al(III) was required to maitain T-P below 0.2 mg/L in the final effluent.

• Journal of Environmental Science International
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• v.8 no.1
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• pp.75-81
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• 1999

In recent years increasing production and disposal of wastewater have caused an accelerated eutrophication of receiving waters. Therefore, in order to alleviate the detrimental impact of wastewater discharge, there is an increasing demand for removing the main nutrients, nitrogen and phosphorus, as well as the organic content of the waste water prior to disposal. This is effectively achieved by extended conventional treatment technology. However, the working expenses and energy requirements of such advanced treatment systems are rather high. So in a sparsely populated rural community is required development of wastewater treatment system combined with the regional characteristics. In this study, the systems are planted with Reeds and Amaryllis In A.C and estimated purification potential of system. The results obtained are as follows. BOD removal rate is 20% in the early stage, the last removal rate is 35% in A.C process and is 65% in Amaryllis+A.C process and is 50% in Reed+A.C process. T-N removal rate by Amaryllis is average 2.6g/$m^3$ㆍd, T-N removal rate by Reed is average 1.76g/$m^3$ㆍd. T-P removal rate by Amaryllis is average 0.27g/$m^3$ㆍd, T-P removal rate by Reed is average 0.25g/$m^3$ㆍd. BOD removal rate constant with retention time is 1.4494(1/d), T-N removal rate constant is 0.5428(1/d), T-P removal rate constant is 0.5287(1/d).

• Membrane and Water Treatment
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• v.14 no.1
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• pp.27-33
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• 2023

In previous studies, solely ferric (Fe³⁺) and calcium (Ca²⁺) ions were commonly used for removal of PO₄-P (considered as T-P in this study) in wastewater via chemical precipitation. Herein, the removal of total phosphorus (T-P) in wastewater was performed using various mineral and lime dissolved solutions. The dissolution kinetics of different minerals (feldspar, olivine, elvan, illite, sericite, and zeolite) and lime was compared and used their solutions for T-P removal of real wastewater. The highest T-P removal (almost 90%) was obtained by the lime dissolved solution and followed by zeolite, illite, feldspar, and others. We observed a significant co-relationship (R of 0.96) between the amount of initial Ca²⁺ and T-P removal. This was induced by formation of hydroxyapatite-like mineral via Ca-P precipitation reaction at high pH solution. Furthermore, additional removal of suspended solid (SS) and chemical oxygen demand (COD) was achieved by only lime dissolved solution. Finally, the lime-feldspar dissolved solutions were prepared at different ratios (10-50%), which showed a successive T-P removal up to two times by samples of 40 and 50%.

• Journal of Korean Society of Water and Wastewater
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• v.13 no.4
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• pp.54-61
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• 1999

SBR process used to evaluate the removal of organics, nitrogen and phosphorus on the basis of a report of research on a precedence at various operation cycle and condition change. Effluent concentration of COD were 50mg/l, 50mg/l, 90mg/l respectively, The removal rates of COD were nearly over 95% at Run 1, 2 and 4. But at Run 3, Effluent concentration of COD was 255.0mg/l, The removal rate of COD was 87% at Run 3. As Oxic/Anoxic rate was fixed and operating cycle of Oxic/Anoxic was changed, the removal rates of T-N were 74.7%, 46.9%, 28.5%, 63.3% respectively at Run 1~4. The case of Run 1 was best result. The removal rates of T-P was appeared in proportion to T-N removal rates and rest of $NO_2-N$. The removal rates of T-P were 51.2%, 35.5%, 41.5%, 51.9% respectively. The removal rates of COD, T-N, T-P were influenced on the change of SBR operation cycle. As organic loading rate was $1.43kgCOD/m^3day$ and C/N ratio was 3.0, operation cycle of Run 1 was best condition of T-N removal rates and T-P removal.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.1
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• pp.131-139
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• 2012

Field experiment was performed from June 2010 to July 2011 to evaluate pollutants removal efficiency in the constructed wetland system for the treated wastewater and the river water. The wetland systems were constructed near Gyungan river. Two different systems with meandering shape were compared for seasonal base and operational period base. Several kinds of aquaculture are planted through the corridor of wetland system. Average removal rate of BOD, T-N and T-P for A system were 15.8%, 14.8% and 26.5%, respectively. Average removal rate of BOD, T-N and T-P for C system were 23.5%, 27.8% and 10.6%, respectively. The effluent from two wetland systems often exceeded effluent water quality standards for wastewater influent, however effluent water quality standards for river water. However, the wetland system can be useful to treat polluted river water and effluent from wastewater plant. Removal rate of pollutants in seasonal variation was the highest in summer for BOD and T-N, however the removal rates of T-P were higher in spring and autumn than in summer.

• Journal of Environmental Health Sciences
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• v.43 no.6
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• pp.525-531
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• 2017

Objectives: The purpose of this experiment is to better understand the nitrogen and phosphorus removal ratio according to operating conditions in an iron electrolysis system consisting of an anoxic basin, aerobic basin, and iron precipitation apparatus. Methods: Iron electrolysis consists of an iron precipitation reactor composed of iron plates in oxic and anoxic basins. We studied the interrelation coefficient between T-N and T-P removal rates and F/M ratio, and the C/N ratio and BOD removal rate. Results: The F/M ratio and the T-N and T-P removal rate per unit area have interrelation coefficients of 0.362 and 0.603, respectively. The removal rate per MLVSS and the T-N and T-P removal rate per unit area have respective interrelation coefficients of 0.49 and 0.59. Conclusions: The removal rate of T-N and T-P increased with the increasing F/M ratio in the influent, and they also linearly increased in proportion to the C/N ratio of influent and BOD removal rate of the reactor.

• Membrane Journal
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• v.20 no.3
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• pp.241-248
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• 2010

The effect of organic material loadings on nutrient removal characteristics were investigated in sequencing batch reactor, in which a flat sheet type microfiltration membrane with a pore size of $0.4\;{\mu}m$ was submerged. Three organic concentrations of 200 mg/L (Run-1), 400 mg/L (Run-2) and 800 mg/L (Run-3) were carried out continuously to identify their effect on the filtration performance and nutrient removal. The removal efficiencies of T-N and T-P were increased with the increase of COD/N and COD/P. The T-N removal efficiencies of Run-1, Run-2 and Run-3 were 28.1, 32.6 and 90.4%, the average concentrations of T-N in permeate were 32.0, 30.0, and 4.3 mg/L, respectively. The T-P removal efficiencies of Run-1, Run-2 and Run-3 were 13.6, 35.3 and 93.1%, the average concentrations of T-P in permeate were 3.11, 2.33, and 0.25 mg/L, respectively.

• Journal of Environmental Health Sciences
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• v.35 no.1
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• pp.64-70
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• 2009

The aims of this study is to examine the effects of the changes in HRT(Hydraulic Retention Time) and media charge in a water-mill, among other operation factors, on the nitrogen and phosphorus removal in order to use up-flow anaerobic reactors, anoxic reactors and water-mill aerobic reactors for sewage treatment. The extension of HRT improved the nitrogen removal efficiency, however the removal pattern was constant regardless of HRT. The removal of phosphorus was constant (80%-90%) regardless of the change in HRT. The removal rate with change in influx load varied such that at the OLR (Organic Load Rate) of 1-3 kg/d, the T-N removal efficiency was 80.7%-88.9% and the T-P removal efficiency was 82.9%-89.3% while at the NLR (Nitrogen Loading Rate) of 0.108-0.156 kg/d the removal efficiencies were 80.7-88.9% (T-N) and 82.9-89.3% (T-P). The analyses of the nitrogen and phosphorous removal characteristics with the C/N and C/P ratio showed that the mean T-N removal rate was 88% at the C/N ratio of 1.2-2.6, and that the mean T-P removal rate was 86% at the C/P ratio of 7.2-14.1. Also, the analysis of nitrogen and phosphorous removal characteristics were analyzed in relation to media charge. The comparison between with and without media charge in the water-mill showed that while the nitrogen removal efficiencies were 86-94% and 85-89% respectively, the difference of phosphorous removal efficiencies were between the two conditions was not significant, thus it suggested that the media charge has less effect on the removal efficiency of phosphorous compared to that of nitrogen.

• Journal of Environmental Science International
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• v.9 no.5
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• pp.415-422
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• 2000

In this study the removal possibility of nutrients of T-P, NH3-N, NO3-N and T-N is examined through a positive experimental study using submerged biofilter of media packing channel method. From the analysis of nutrients removal efficiency for each run of the collected sample following results are obtained. Firstly the result of N/P surveying for inflow shows serious value that excess the limit value of 20 as the values are in the range of 12.0~42.7 and the average is 25.73. Secondly the highest concentration of the incoming NH3-N reaches double of the standard since the concentrations of NH3-N and NO3-N for inflow shows 0.06mg/$\ell$ and 2.5~3.8mg/$\ell$ respectively and the average removal rate which passed the submerged biofilter adopted in this study is a satisfactory level. Next the average removal rate of T-P of 51.5% shows the possiblity of entrophication removal since the removal rate of T-P of 66.8~68.8% in relative low temperature period of RUN 1~2 appeared higher than in RUN 3~6 and T-N shows relatively poor result with the average removal rate of 34.1% And it is known that the bigger BOD/P and BOD/N are the more removal rate increases from the examination result of the relation between BOD/P and BOD/N and the treatment water T-P and T-N to decide the relation with the concentration of organic matters and though that the appropriate proportion is necessary for effective removal of nitrogen and phsophorus.

• Journal of Wetlands Research
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• v.11 no.3
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• pp.37-47
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• 2009

This research was conducted at the constructed wetland in Goheung reclaimed land, and water quality components were measured at the 12 points in 15 March 2008 and 10 January 2009, respectively. Temperature, pH, DO, EC and salinity components were measured at the field, and TOC, Cl-, COD, TSS, T-P and TN components were analyzed laboratory. Concentrations of field measured components at inflow points were higher than in constructed wetland. TOC concentration ratio of inflow water to constructed wetland water was higher in January, and Cl concentration ratio of it was higher in March. And, COD concentration ratio of it were 1.37 for March and 1.49 for January, respectively. T-P and T-N concentration ratios of it at inflow points were higher 3 times than in constructed wetland. Constructed wetland attenuated concentration of contaminated components inflow to it. Removal efficiencies of Cl-, T-P and T-N components in inflow water were high at the constructed wetland. removal efficiencies of Cl component were 83% for 1st monitoring and 76% for 2nd monitoring, this removal efficiency be caused by dilution effect of constructed wetland. removal efficiencies of T-P component were 67% for 1st monitoring and 69% for 2nd monitoring, and they of T-N component were 100% for 1st monitoring and 95% for 2nd monitoring. Abnormal removal efficiency of T-N component is caused that nitrogen in inflow water was a little. Removal efficiency of T-P component was higher in January, and T-N component was higher in March. This is caused by environmental difference between growing season and winter.