• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.505-510
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• 1992

The experiments were carried out to study the effect of physical forms of hay diet on phosphorus metabolism by offering sheep roughage diets containing a low phosphorus content. The sheep were fed coarse hay, short hay or finely ground pelleted hay. The physical forms of hat diet had little effect on the pathway of phosphorus excretion. In all groups, the most of phosphorus was excreted in feces and urinary phosphorus excretion was negligible. Duodenal fluid flow, rumen fluid outflow and estimated salivary flow appeared to be relatively high in sheep fed the coarse hay diet as compared to those in sheep fed the finely ground diet. The amount of phosphorus flow to the duodenum tended to be high in the coarse diet group as compared to those in other two groups. On the other hand, phosphorus concentrations in the duodenal fluid and the rumen fluid were lower in sheep fed the coarse hay diet than those in sheep fed the ground hay. Net intestinal phosphorus absorption tended to be higher in sheep fed the coarse hay than that in sheep fed the ground hay or pelleted hay. However, a negative phosphorus balance was observed in the coarse hay diet group although a positive phosphorus balance was found in other two groups. It was considered that salivary phosphorus secretion was greater than the amount of salivary phosphorus reabsorbed from the intestine, resulting in the negative of phosphorus balance in sheep fed the coarse hay.

• 한국물환경학회지
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• 제18권2호
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• pp.123-130
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• 2002

Bench scale experiments were carried out with two biological nutrient removal(BNR) units, A/O and $A^2O$ processes, to investigate the behavior of phosphorus in the system and to compare the characteristics of phosphorus removal in two BNR processes. To achieve this goal, COD/T-P and COD/TKN ratios of the influent was varied in the range of 23~64 and 5~24, respectively. In A/O process, influent COD/T-P ratio should be kept higher than 44mg/L to meet the final effluent T-P concentration lower than 1mg/L and in $A^2/O$ process, influent COD/T-P and COD/TKN ratios higher than 56 and 10, respectively, were required for good phosphorus release and uptake with no influence of nitrate nitrogen in return sludge. At this conditions, the rate of phosphorus release in the anaerobic basin should be kept higher than 0.1 kg S-P/kg MLVSS d In A/O process, the phosphorus content of anaerobic and aerobic sludges was increased as SRT of total system was becoming longer resulting in decreasing the difference of phosphorus content between two sludges while phosphorus release in anaerobic basin and phosphorus uptake in aerobic basin was not incident. In $A^2/O$ process, the phosphorus content of anaerobic and aerobic sludges were not increased with higher SRT of total system due to the relatively high nitrate concentration in return sludge. However, the difference of phosphorus content between anaerobic and aerobic sludges was incident when phosphorus release and uptake was observed.

• 한국토양비료학회지
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• 제21권3호
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• pp.272-279
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• 1988

토양(土壤)의 인산함량(燐酸含量)과 인산(燐酸)의 고정력(固定力)이 상이(相異)하고 토양(土壤)의 특성(特性)을 달리하는 11개(個) 밭토양(土壤)에서 인산(燐酸)을 여러 수준(水準)으로 시용(施用)하고 대두(大豆)를 재배(栽培)하여 토양(土壤)의 여러 인산분획물(燐酸分劃物)이 대두(大豆) 수량(收量)에 미치는 영향(影響)과 인산(燐酸) 분획물(分劃物)들 간(間)의 관계(關係)에 대하여 검토(檢討)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 토양중(土壤中) 유효인산함량(有效燐酸含量)이 낮고 인산(燐酸)의 고정력(固定力)이 큰 토양(土壤)에서 인산(燐酸)의 비효(肥效)가 컸으며 대두(大豆) 수량(收量)은 유효인산(有效燐酸) 및 무기태인산함량(無機態燐酸含量)과 유의성(有意性)있는 정(正)의 상관관계(相關關係)를 보였다. 2. 토양(土攘)에 시용(施用)된 인산(燐酸)이 유효인산(有效燐酸) 으로 변화(變化)되는 비율(比率) 즉 유효인산화율(有效燐酸化率)은 2.5-91.7% 범위(範圍)로 토양(土壤)의 종류(種類)에 따라 상이(相異)하였으며 평균(平均) 48.5%이었다. 3. 대두(大豆) 수량(收量), 식물체(植物體) 인산함량(燐酸含量) 및 흡수량(吸收量)과 개화기(開化期)기 토양중(土壤中)의 유효인산(有效燐酸) 및 무기태(無機態) 인산함량(燐酸含量)과의 관계(關係)에서 대두(大豆) 수량(水量)은 유효인산(有效燐酸), Al-P 및 Ca-P와 식물체(植物體) 인산함량(燐酸含量) 및 흡수량(吸收量)과는 Fe-P를 제외(除外)하고 모두 유의성(有意性) 있는 상관관계(相關關係)를 보였으나, Fe-P함량(含量)도 제주통(濟州統)을 분리(分籬)해서 보면 유의성(有意性)있는 상관관계(相關關係)를 보였다. 4. 개화기(開花期) 토양중(土壤中) Al-P/Fe-P 비(比)는 인산(燐酸) 시용량(施用量)이 증가(增加)함에 따라 증가(增加)되었으며, 그 증가폭(增加幅)은 토양(土壤)의 종류(種類)에 따라 상이(相異)하였고, 대두수량(大豆收量), 인산(燐酸) 흡수량(吸收量), 토양(土壤) 및 식물체(植物體) 인산함량(燐酸含量)과 유의성(有意性) 있는 정(正)의 상관관계(相關關係)를 보였으나, Fe-P와는 유의성(有意性) 있는 상관관계(相關關係)를 보이지 않았다. 5. 개화기(開化期) 토양(土壤)의 인산(燐酸) 흡수량(吸收量)은 인산(燐酸) 시용량(施用量)이 증가(增加)함에 따라 점점 감소(減少)되었으며, 감소(減少) 정도(程度)는 인산(燐酸)의 고정력(固定力)이 낮은 토양(土壤)에서 크고 인산(燐酸)의 고정력(固定力)이 큰 토양(土壤)에서 작았다. 한편 토양(土壤)의 인산(燐酸) 흡수량(吸收量)은 토양(土壤) 및 식물체(植物體) 인산함량(燐酸含量), 식물체(植物體) 인산(燐酸) 흡수량(吸收量), 무기태(無機態) 인산(燐酸)(Sa-P, Al-P, Ca-P) 함량(含量)과 유의성(有意性) 있는 부(負)의 상관관계(相關關係)를 보였으며, 수량(收量)과는 유의성(有意性)은 없었지만 부(負)의 상관경향(相關傾向)을 보였다.

• 상하수도학회지
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• 제34권6호
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• pp.437-443
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• 2020

Biological phosphorus removal is accomplished by exposing PAO(phosphorus accumulating organisms) to anaerobic-aerobic conversion conditions. In the anaerobic condition, PAO synthesize PHB(polyhydroxybutyrate) and simultaneously hydrolysis of poly-p resulting phosphorus(Pi) release. In aerobic condition, PAO uptake phosphorus(Pi) more than they have released. In this study, cyanobacteria Synechococcus sp., which is known to be able to synthesize PHB like PAO, was exposed to anaerobic-aerobic conversion. If Synechococcus sp. can remove excess phosphorus by the same mechanism as PAO, synergistic effects can occur through photosynthesis. Moreover, Synechococcus sp. is known to be capable of synthesizing PHB using inorganic carbon as well as organic carbon, so even if the available capacity of organic carbon decreases, it was expected to show stable phosphorus removal efficiency. In 6 hours of anaerobic condition, phosphorus release occurred in both inorganic and organic carbon conditions but SPRR(specific phosphorus release rate) of both conditions was 10 mg-P/g-MLSS/day, which was significantly lower than that of PAO. When converting to aerobic conditions, SPUR(specific phosphorus uptake rate) was about 9 mg-P/g-MLSS/day in both conditions, showing a higher uptake rate than the control condition showing SPUR of 6.4 mg-P/g-MLSS/day. But there was no difference in terms of the total amount of removal. According to this study, at least, it seems to be inappropriate to apply Synechococcus sp. to luxury uptake process for phosphorus removal.

• 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.

• 상하수도학회지
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• 제33권4호
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• pp.291-297
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• 2019

Phosphorus is a vital resource for sustaining agriculture and nutrition, but a limited non-renewable resource. Thus, the recovery of phosphorus from waste activated sludge(WAS) was attempted by microwave heating and magnesium ammonium phosphorus(MAP) crystallization. Polyphosphate-accumulating organisms(PAOs) in WAS release phosphate from the cell when they are exposed to high temperature environments. Microwave heating caused phosphorus and ammonia to release from WAS. The amount was increased with increasing temperature, showing that 88.5% of polyphosphate present in the cells were released in the form of phosphate at $80^{\circ}C$. A similar result was also observed in the release of ammonia. On the other hand, both phosphorus and ammonia were crystallized with magnesium, and then was harvested as MAP. Phosphorus recovery rate reached almost 97.8%, but the ammonia was about 13.4%. These results cleary indicate that phosphorus could be recovered from WAS using a physiological trait of PAOs. Heavy metal analyses also show that the MAP crystal is useful and safe as a phosphorus fertilizer.

• Asian-Australasian Journal of Animal Sciences
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• 제12권4호
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• pp.651-656
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• 1999

In current animal production in Japan, a large surplus of nitrogen and phosphorus is given to animals as their feed which are mostly imported from outside of our own country. Today, an excess of nitrogen and phosphorus from animal manure has been spread out of the area of animal production and the surroundings. These components have become the major reason for eutrophication of ground, surface and inland water. Nutritional studies for the reduction of nitrogen and phosphorus from animal waste has been done by many researchers. The reduction of excess protein in animal feed and the supplementation of deficient essential amino acids to feed have a possibility to increase the biological value of feed and to reduce nitrogen excretion, especially, via urine. The use of phytase activity to degrade phytate and to release utilizable inorganic phosphorus make it possible to cut an excess supply of feed additive inorganic phosphorus and to reduce phosphorus excretion from animal waste.

• 상하수도학회지
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• 제12권2호
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• pp.59-66
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• 1998

The feasibility of usage of sludge from water treatment plant and chalk from schools and institutes was investigated to remove the phosphorus in the lakes which induce the eutrophication every year. In this study phosphorus removal efficiencies of sludge and chalk were investigated by changing various factors. Higher phosphorus removal efficiency using larger particle size of chalk was observed which means that the surface area is not an important factor in removing phosphorus in aqueous phase. The proper shaking time and temperature were 2 hours and $25^{\circ}C$, respectively. The removal efficiency using sludge from water treatment plant was almost 100%, which is similar to those of CaO and $Ca(OH)_2$. It means that sludge can be reused in removing phosphorus. It was also found that chalk was better in removing phosphorus under alkaline condition and sludge was better under acidic condition. About 75% phosphorus removal efficiency was observed using sludge from the water sample in Lake Sihwa.

• Asian Journal of Atmospheric Environment
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• 제7권3호
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• pp.169-175
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• 2013

Measurement of the phosphorus concentration in aerosols in Beijing, which was a representative East Asian mega-city, was carried out. The optimum procedure for analyzing phosphorus in aerosols was found in this study. Recovery of phosphorus in environmental samples through the improved method was almost 100%. The concentration of phosphorus in TSP was $145{\pm}47\;ng/m^3$, with a seasonal variation showing high concentrations in winter and low concentrations in summer. The concentrations of phosphorus in $PM_{2.5}$ accounted for $35{\pm}6%$ of those in TSP, with no seasonal variations. The major source of phosphorus in aerosols in Beijing was soil dust, and additional sources of phosphorus in fine particles could be coal combustion and biomass burning.

• Carbon letters
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• 제11권2호
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• pp.112-116
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• 2010

The objective of this study was to evaluate the possibility of simultaneous removal of ammonium, nitrate and phosphorus in water using the zeocarbon. In this study, the surface of zeocarbon was modified by acid because of difficulty in application of water treatment. After surface modification, the strength was enhanced about 62% higher than that of original one. The removal efficiency of ammonium and nitrate using the modified zeocarbon was about 47% and 32%, respectively and were higher than that of zeocarbon. In batch type experiment on the simultaneous removal of ammonium, nitrate and phosphorus, the presence of phosphorus did not have influence on nitrogen removal efficiency. Concomitantly, removal efficiency of phosphorus was obtained was about 35%. This indicates that the surface modified zeocarbon can be applied for simultaneous removal of nitrogen and phosphorus. Consequently, our results could be used as basic data to design of one-stage nitrogen/phosphorus simultaneous removal system.