• 한국환경과학회지
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• 제8권6호
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• pp.705-710
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• 1999

The fundamental experiments on the phosphorus removal from water were carried out by the batch and continuous reactors which used aluminium and copper plate. In this systems, the phosphorus was removed by aluminium ion generated with the electrochemical interaction (pitting corrosion) of aluminium and copper. In the batch experiments, the efficiencies of phosphorus removal increased when the surfaces of aluminium and copper plate were brushed. The phosphorus removal by aluminium ion was affected the copper plate and NaCI in this system. The optimal pH values were 5 and 6 for the phosphorus removal. The efficiency of phosphorus removal increased with increasing NaCI concentration, surface area of aluminium and copper plate. The $CUSO_4{\cdot}5H_2O$ instead of copper plate could be used as Cu source. The effluent $PO_4-P$ concentration as low as 2 $mg/{\ell}$ could have been obtained during the continuous experiment at HRT of 48 hrs.

• 해양환경안전학회지
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• 제14권2호
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• pp.105-109
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• 2008

우리나라에서 대부분의 호수는 인이 제한영양염인 것으로 나타나고 있다. 그러므로 인의 제거는 하수처리에서 중요한 공정이라고 할 수 있다. 그러나 많은 하수처리장은 재래식처리공정으로 처리하고 있으며 인의 제거율이 $10{\sim}30%$로 낮게 나타나 인의 제거공정은 필요하게 되었으며 패각은 수중의 인을 제거할 수 있는 것으로 알려지고 있어서 인의 활용이 주목된다. 회분식으로 패각을 이용하여 인의 제거율을 조사한 결과 패각의 크기가 작을수록, pH가 높을수록 제거율이 높게 나타났다. 또한 칼슘의 주입농도를 달리하여 처리한 결과 칼슘의 농도가 높을수록 처리효율이 증가하였으며 칼슘의 농도를 20mg/L로 조절하여 실험한 결과 2시간 내에 90% 이상의 제거율을 나타내었다. 재순환을을 변화시켜 실험한 결과 재순환율이 증가할수록 제거율은 증가하였으며 PH 11에서 재순환율을 300%로 조절한 결과 인의 제거율은 80%가 되었다. 중탄신이온의 영향을 평가하기 위하여 중탄산이온의 농도를 달리하여 실험한 결과 중탄산이온의 증가에 따라 인의 제거율은 감소하는 것으로 나타났으며 감소하는 비율은 지수함수로 나타났다.

• 한국환경과학회지
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• 제6권5호
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• pp.521-529
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• 1997

In the study, we Investigated the behavior and removal efficiency of organics, nitrogen. phosphorus with operating conditions in SBRs. Substrate used was synthetic wastewater in which the ratio of $COD_{cr}$. : N : P was 100 : 12 : 2. The cycling the in SBRs was adjusted at 6 hours and 8 hours, and then certainly Included anaerobic and aerobic conditions. Also, for each cycling time. we performed 2 series of experiment simultaneously which was set up 10 days and 20 days as SRT. The removal efficiency of $COD_{cr}$. was over 97% in all operating conditions. In the 6 hours cycling time, the removal efficiency of $PO_4^{3-}-P$ reached almost 100% in steady state. And then we could observe a typical phonemena of phosphorus release and uptake, and the removal efficiency of N was 67%, Residual N source was almost TKN and most of the rest remained as $NO_2-N$. Also the difference in both SRTs was not observed practically. In the 8 hours cycling time, dissolution of sludge appeared. and, $PO_4^{3-}-P was not nearly removed but nitrogen was removed up to 75%, And the residual nitrogen was accumulated as $NO_2^--N$.

• 상하수도학회지
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• 제26권3호
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• pp.443-451
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• 2012

Wastewater treatment plants need to reduce phosphorus in order to meet increasingly stringent regulations on phosphorus. This study evaluated the feasibility of dolomite as a coagulation aid to enhance phosphorus removal from secondary treated wastewater by chemical coagulation. Standard jar tests were conducted to evaluate the effect of dolomite addition on a coagulation process for phosphorus removal and to determine the optimum doses of coagulants and dolomite. Coagulants used with dolomite yielded a significant improvement in phosphorus removal and reduced total phosphorus concentrations below 0.02 mg/L in wastewater effluent. Dolomite has played an important role in enhancing phosphate adsorption and increasing pH, as a coagulation aid. The maximum removal efficiency of phosphorus in this study was yielded at 25 mg/l of dolomite and 20 mg Al/L of PAC dose. However, considering economic aspects, the optimum doses of dolomite and PAC were 10 mg/L and 15mg Al/L, respectively. Consequently, dolomite, a coagulation aid, can be used in coagulation processes to enhance the removal of phosphorus.

• 한국환경보건학회지
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• 제35권3호
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• pp.214-219
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• 2009

This study examined the removal efficiency of the nitrogen and phosphorus in order to compensate for the combined process of ATAD(Autothermal Thermophilic Aaerobic Digestion) and EGSB(Expended Granular Sludge Bed), which are treatment methods for livestock wastewater, by introducing SBR(Sequencing Batch Reactor) as post-treatment process. The analysis on the treatment efficiency of each operation mode showed that, in the case of T-N, the treatment efficiency were 67.1% and 74.2% for Run-1 and Run-2, respectively, and in the case of T-P, the values were 71.2 and 74.1, respectively, which are indicating that the treatment efficacy is higher in the condition of Run-1, in which the time period of Anoxic and Aerobic segments were increased. In addition, the result of analyzing removal characteristics of nitrogen and phosphorus by Influx load showed that removal efficiency of nitrogen was better in the case of high influx load than in the case of low influx load. Regardless of Influx load, phosphorus showed constant influx concentration, so that removal efficiency of phosphorus was influenced littler by Influx load than that of nitrogen. This study also fed methanol as an external carbon source and performed experiment to induce denitrification under anoxic condition by using nitrate among nitrogen compounds of SBR reactor, and the results showed that intermittent feeding was more effective in Nitrogen Removal than composite feeding.

• 한국환경보건학회지
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• 제25권3호
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• pp.70-76
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• 1999

A laboratory experiment was performed to investigate the phosphorus removal using the activated sludge-electrolysis reactor which consisted of A$^2$/O system and aluminium electrodes as cathode and anode. In this system, the phosphorus was removed by aluminium ion, which was eluted from aluminiumelectrodes by electrolysis. In the batch experiments, when the current densities were 0.026, 0.052 and 0.08 A/dm$^2$, the phosphorus removal efficiencies for synthetic sewage were 66.4, 86.4 and 98.7% respectively. These results showed that the phosphorus removal efficiency increased with the increase of the current density. When the current values were 13, 26 and 40 mA respectively, the amounts of Al$^{3+}$ eluted from electrodes according to Faraday's law were 0.049, 0.07 and 0.12 g and Al/P mole ratio were 1.1, 2.0 and 3.41. In the continuous experiments, As hydraulic retention time(HRT) increased, COD and total nitrogen(T-N) removal efficiencies for domestic sewage increased. The average phosphorus removal rates of the activated sludge-electrolysis system were 97, 91, 80 and 80% at the HRT of 48, 24, 18 and 12 hours, respectively. Especially, the phosphorus removal rate in the activated sludge system with aluminium electrodes was higher than that in the system without aluminium electrodes.

• 한국습지학회지
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• 제14권4호
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• pp.629-635
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• 2012

본 연구는 부영양화 호소의 개선을 위하여 분말활성탄 공정을 적용하고 호소수 내의 용존 유기물과 인의 제거특성을 파악하고자 수행되었다. 용존 유기물의 제거특성은 부유물질의 제거특성과 다르며 응집제 주입량과 pH에 영향을 받음을 확인하였다. 용존 유기물은 분말활성탄에 의해 흡착으로 제거되며 응집과정에서 용존 유기물의 제거효율을 증가시킬 수 있었다. 응집침전공정의 인 제거 과정과 같은 화학침전과정에서 형성되는 용존성 착화합물과 콜로이드성 물질은 인의 제거효율을 저하시키는 요인이다. 분말활성탄의 주입으로 콜로이드성 물질과 용존성 착화합물을 흡착함으로써 인의 제거효율을 증가시킬 수 있었다. 또한 분말활성탄은 응집과정의 floc의 밀도를 증가시켜 침전속도를 높이고 고액분리 효율을 높일 수 있었다.

• 한국물환경학회지
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• 제18권3호
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• pp.291-301
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• 2002

In this study, nutrients treatment by sequencing batch reactors(SBR) was performed. Nitrogen and phosphorus removal efficiencies were evaluated by changing SRT and mixing/aeration ratio. Not only nitrogen but also phosphorus removal patterns were investigated through track studies on 1 cycle. As SRT was fixed and mixing/aeration ratio was changed, maximum nitrogen removal efficiency was 87.6% at mixing/aeration ratio 0.67. Phosphorus removal efficiencies were more than 85.5% except no mixing condition. As mixing/aeration ratio was fixed and SRT was changed, nitrogen removal efficiencies were 70.5~79.8%, which represented slight changes, while phosphorus removal efficiencies were 49.0~97.3%, which represented sharply decreasing tendency at less than 20 day. Both phosphorus release rate k and maximum phosphorus release rate $P_{max}/M$ were are decreased as SRT was decreased, but they were not affected by mixing/aeration ratio. It was found that there is a linear relationship between ortho-phosphate uptake and maximum ortho-phosphate release.

• 상하수도학회지
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• 제32권1호
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• pp.47-53
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• 2018

This study investigated phosphorus removal from secondary treated effluent using coagulation-membrane separation hybrid treatment to satisfy strict regulation in wastewater treatment. The membrane separation process was used to remove suspended phosphorus particles after coagulation/settlement. Membrane separation with $0.2{\mu}m$ pore size of micro filtration membrane could reduce phosphorus concentration to 0.02 mg P/L after coagulation with 1 mg Al/L dose of polyaluminum chloride (PACl). Regardless of coagulant, the residual concentration of phosphorus decreased as the dose increased from 1.5 to 3.5 mg Al/L, while the target concentration of 0.05 mg P/L or less was achieved at 2.5 mg Al/L for the aluminum sulfate (Alum) and 3.5 mg Al/L for PACl. Moreover, alum showed better membrane flux as make bigger particles than PACl. Alum showed a 40% of flux decrease at 2.5 mg Al/L dose, while PACl indicated a 50% decrease of membrane flux even with a higher dose of 3.5 mg Al/L. Thus, alum was more effective coagulant than PACl considering phosphorus removal and membrane flux as well as its dose. Consequently, the coagulation-membrane separation hybrid treatment could be mitigate regulation on phosphorus removal as unsettleable phosphorus particles were effectively removed by membrane after coagulation.

• 한국물환경학회지
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• 제31권6호
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• pp.619-624
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• 2015

This study experimentally determined the effect of titanium tetrachloride (TiCl₄) concentration ([TiCl₄]) (0.25-0.55 mM) and initial pH (3-11) on phosphorus (P) removal in synthetic wastewater (2 mg P/L). The P removal efficiency increased when [TiCl₄] increased. The P removal efficiency showed a parabolic trend with an inflection point at pH 7. At the molar ratio of TiCl₄ and P>6.2, the P removal efficiency was over 90% and the residual P concentration was less than 0.2 mg/L. Within the design boundaries, the complete P removal could be achieved at 7.0≤initial pH≤8.5 and 0.43≤[TiCl₄]≤0.55 mM. The final pH was over 5.8 at initial pH≥7.7 and [TiCl₄]≥0.35 mM. The results showed that TiCl4 was effective in P removal in water so that it could be an alternative chemical for P removal.