• Asian-Australasian Journal of Animal Sciences
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• 제16권2호
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• pp.239-247
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• 2003

Two experiments were conducted with broilers to investigate the feasibility of microbial phytase replacing partial inorganic phosphorus supplementation and the synergistic effects of xylanase (320 FTU/kg) supplementation alone or in combination with phytase (750 U/kg) replacing 0.08% dietary inorganic phosphorus, on the growth performance and utilization of nutrients in broilers fed wheat-based diets. In Experiment 1, 540 broilers were fed five diets for 6 weeks. Diets C0 and C1 were corn-based diets and 0.08% inorganic P supplementation was replaced with 750 U phytase/kg feed in Diet C1. Diets W0, W1 and W2 were wheat-based diets supplemented with microbial phytase 0, 750, 750 U/kg feed and 0, 0.08% and 0.16% dietary inorganic P were replaced, respectively. In Experiment 2, 432 broilers were divided into four treatments to determine the synergistic effects of supplemental xylanase and phytase replacing 0.08% inorganic P. Four experimental diets were arranged according to a $2{\times}2$ factorial design. The results indicated that addition of phytase increased the digestibility of phytic P by 31.0 to 55%, dramatically decreased the excretion of phytic P and total P by 31.6 to 55.0% and 13.8 to 32.9%, respectively (p<0.01). It is feasible to completely replace 0.08% inorganic phosphorus supplementation with microbial phytase 750 U/kg in corn- or wheat-based diets for broilers. Addition of xylanase alone or in combination with phytase replacing 0.08% dietary inorganic P, increased body weight gain and feed utilization efficiency of broilers fed wheat-based diets (p<0.10) and decreased overall mortality (p<0.10). In the groups of birds supplementing xylanase 320 FTU/kg feed, a marked elevation of the dietary AME was observed (p<0.05). Addition of phytase replacing 0.08% dietary inorganic phosphorus, concurrently with xylanase supplementation had additive effects on the apparent digestibility of dietary phytic P and overall feed conversion ratio (p<0.05).

• 한국환경과학회지
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• 제28권5호
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• pp.511-520
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• 2019

This study was investigated to improve the phosphorus release and water quality by transformation of sedimentary P fraction for application of $CaO_2$. For the experiment, 0.5% (w/w) of $CaO_2$ was homogenized in the sediment and incubated with the control for 20 days. The analytical results showed that pH increased with $CaO_2$ and redox potential (ORP) was improved in the sediment of the reactor. The growth rate of chlorophyll-a was lower in the $CaO_2$ reactor and Dissolved Oxygen (DO) of overlying water maintained higher than that of the control. Total phosphorus (T-P) concentration in the overlying water increased from the initial concentration to 0.304mg/L in the control at 20 days. The reactor of $CaO_2$ was lowered by 29.3%. Ex-P, Fe-P and Ca-P in sediment P fraction were increased with the $CaO_2$. The formation of bound Fe-P and Ca-P in the sediments seemed to control the release of P by removing the Soluble Reactive Phosphorus (SRP) presented in the pore water. From the result, this indicated that the reduction of P release from the sediments seems to be effective in suppressing the eutrophication of P and improving the oxygen condition in the water quality with the application of $CaO_2$.

• Membrane and Water Treatment
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• 제11권1호
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• pp.59-68
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• 2020

The study objective was to evaluate the enhanced removal of high concentrations of phosphorus from synthetic wastewater (solely phosphorus-containing) and real wastewater (pig manure) by using carbon nanotube (CNT)-coated steel slag. Generally, phosphorus removal by steel slag is attributed to Ca²⁺ eluted from the slag. However, in this study, CNT was used to control the excess release of Ca²⁺ from steel slag and increase the phosphorus removal. The phosphorus removal rate by the uncoated steel slag was lower than that of the CNT-coated steel slag, even though the Ca²⁺ concentrations were higher in the solution containing the uncoated steel slag. Therefore, the phosphorus removal could be attributed to both precipitation with Ca²⁺ eluted from steel slag in aqueous solution and adsorption onto the surface of the CNT-coated steel slag. Furthermore, the protons released from the CNT surface by exchanging with divalent cations acted to reduce the pH increase of the solution, which is attributed to the OH^- eluted from the steel slag. The adsorption isotherm and kinetics of the CNT-coated steel slags followed the Freundlich isotherm and pseudo-second-order model, respectively. The maximum adsorption capacity of the uncoated and CNT-coated steel slags was 6.127 and 9.268 mg P g^-1 slag, respectively. In addition, phosphorus from pig manure was more effectively removed by the CNT-coated steel slag than by the uncoated slag. Over 24 hours, the PO₄-P removal in pig manure was 12.3% higher by the CNT-coated slag. This CNT-coated steel slag can be used to remove both phosphorus and metals and has potential applications in high phosphorus-containing wastewater like pig manure.

• 분석과학
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• 제24권5호
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• pp.378-386
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• 2011

본 연구는 호수바닥에 있는 침전물로부터 인의 용출 메커니즘을 규명하고자, 인이 물로 용출될때 미치는 온도의 영향을 조사하였다. 연구 결과를 보면, 온도가 증가하면 PO4-P가 평형에 빨리 도달하고, 평형농도가 증가하며, $PO_4$-P의 용출 증가로 인하여 pH가 감소한다. 즉, $PO_4$-P의 용출이 pH의 감소에 영향을 미침을 알 수 있었다. 탁도물질에서 용출된 $PO_4$-P는 물에 용존하며, 탁도물질에 흡착되지 않기 때문에 탁도의 변화에 관계없이 점진적인 증가를 나타냈지만, $PO_4$-P는 탁도에서 용출되기 때문에 탁도와 관련이 있다. 총인(Total phosphorous, T-P)은 용존성 $PO_4$-P와 탁도물질에 포함된 인을 포함하기 때문에 탁도의 변화에 직접 관련이 있음을 알 수 있었다. 온도가 감소하면 물의 밀도가 증가하여 탁도의 침전이 감소하기 때문에 탁도의 농도가 높아져 T-P 농도를 증가시키며, 온도가 증가하면 물의 밀도감소로 인하여 탁도물질의 침전이 용이해져서 탁도는 감소하지만 $PO_4$-P의 용출이 증가하여 T-P 농도가 증가했다. 따라서 동일 시간대의 T-P는 온도가 달라도 유사한 농도를 가졌다. 호수가 깊어지면 저층수의 온도가 감소하여 인의 용출이 감소하므로 이 메카니즘은 호수 바닥으로부터 물로 용출되는 인에 대하여 온도가 미치는 영향을 이해하는데에 중요하다.

• 한국토양비료학회지
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• 제10권1호
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• pp.13-22
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• 1977

우리나라 주요토양(主要土壤)에 있어서 인산(燐酸)이 어떠한 형태(形態)로 분포(分布)하고 있으며, 그 토양인산(土壤燐酸)의 특성(特性)이 어떠한지를 밝히고 나아가 인산질자원(燐酸質資源)을 합리적(合理的)으로 사용(使用)하기 위한 기본적(基本的)인 정보(情報)를 얻고저 본시험(本試驗)을 실시(實施)했든바, 그 중(中)에서 무기태인산(無機態燐酸)에 관(關)한 연구결과(硏究結果)는 다음과 같다. 1. 일반적(一般的)으로 대부분(大部分)의 인산(燐酸)은 무기태(無機態)로 존재(存在)하며, 경작지(耕作地)는 미경지(未耕地)에 비(比)해 무기태(無機態)로 존재(存在)하는 인산비율(燐酸比率)이 더 높은 것으로 나타났다. 유기인산(有機燐酸)의 비율(比率)은 미경지(未耕地)보다 경지(耕地), 전(田)보다 답(畓)에서 더 높았다. C/P율(率)은 경지(耕地)보다 미경지(未耕地)에서 매우 크며, 그 비율(比率)과 인산지력(燐酸地力)과의 관계(關係)를 추측(推測)되었다. 2. 무기태인산(無機態燐酸)의 일반적(一般的)인 분포(分布)는 Fe-P>Al-P>Apatire-P>Ca-P의 순(順)이었다. 미경지(未耕地)에서는 모암(母岩)의 영향(影響)이 잘 반영(反影)돼 있으며, 이 경향(傾向)은 전(田)으로 이용(利用)되고 있는 토양(土壤)에 까지 다소(多少) 나타났으나, 답(畓)에서는 거의 똑같은 분포상태(分布狀態)가 나타났다. 3. 일반적(一般的)으로는 미경지(未耕地) 및 전토양(田土壤)에서 Lancaster법(法)으로 침출(浸出)된 인산(燐酸)이, 답(畓)에서는 Olsen법(法)에 의(依)한 침출인산(浸出燐酸)이 가장 높았다. Ca-P, Al-P는 Truog법(法), Lancoster법(法), Olsen법(法)에 의(依)한 유효인산(有効燐酸)과, Fe-P는 Olsen법(法)에 의(依)한 유효인산(有効燐酸)과 깊은 상관관계(相關關係)를 보였다. 4. 인산흡수계수(燐酸吸收係數)와 무기태인산(無機態燐酸) 및 유효인산(有効燐酸) 사이에 깊은 상관관계(相關關係)가 인정(認定)되었다.

• 한국초지조사료학회지
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• 제21권4호
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• pp.181-190
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• 2001

This study was conducted to investigate the effect of swine liquid manure(SLM) and phosphorus fertilizer from September, 1998 to July, 1999 on the soil fertility on Italian ryegrass field, Cheju volcanic ash soil. pH(lst investigated), Mg (2nd investigated) and Cu content (2nd investigated) on soil grown by Italian ryegrass were significantly increased by an increase of fertilizer P(P

• 산업기술연구
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• 제26권B호
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• pp.3-10
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• 2006

In this study, the of MBBR(moving bed biofilm reactor) process for Phosphorus Removal efficiency depending on seasons and the factors affecting phosphorus removal efficiency in the process is evaluated. As a result of experiment, T-P removal efficiency has its highest value in winter, (80.8%). and T-P removal efficiency has its lowest value in autumn, (49%). Optimum SRT for Phosphorus Removal revealed is about 8.8 days and process performs more efficiently as the temperature decreases. It is accepted that nitrate to anaerobic zone is affecting the Phosphorus removal process. With increasing the organic loading rate, Phosphorus removal efficiency also increases. Also, an experiment has been conducted to find out the highest efficiency according to Media existence and it has revealed that Media addition provides better phosphate removal.

• 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.

• Journal of Applied Biological Chemistry
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• 제54권3호
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• pp.225-229
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• 2011

본 연구는 호수바닥에 있는 인의 용출 메카니즘을 규명하고자 유기물이 없는 시료(흙)에 호기성과 혐기성 실험하여 인 용출을 연구하였다. T-P의 증가 대부분은 $PO_4-P$ 증가에서 기인됐고, 약 pH 4-7 정도에서 $PO_4-P$는 호기, 혐기 그리고 pH 변화에도 점진적인 증가를 나타낸 원인은 한번 용출된 $PO_4-P$는 탁도에 흡착되지 않고 용존 하면서 계속해 탁도물질에서 $PO_4-P$를 용출하기 때문이다. T-P, 탁도, pH 그리고 DO의 유사한 변화 양상은 시료의 포도당 분해 시 DO 감소로 혐기화되면 유기산이 생성되어 pH가 감소하고, 탁도물질은 pH 감소로 침전이 촉진되며, 침전된 탁도물질은 미생물의 분해작용이 없어도 인이 용출된다. 이 메카니즘은 호수 바닥으로부터 물로 공급되는 인을 이해할 때 대단히 중요하다.

• 상하수도학회지
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• 제31권6호
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• pp.577-586
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• 2017

One of the major sources causing eutrophication and algal blooms of lakes or streams is phosphorus which comes from point and nonpoint pollution sources. HAP (hydroxyapatite) crystallization using granular alkaline materials can achieve the decrease of phosphorus load from wastewater treatment plants and nonpoint pollution control facilities. In order to induce HAP crystal formation, continuous supply of calcium and hydroxyl ions is required. In this research, considering HAP crystallization, several types of lime-based granular alkaline materials were prepared, and the elution characteristics of calcium and hydroxyl ions of each were analyzed. Also, column tests were performed to verify phosphorus removal efficiencies of granular alkaline materials. Material_1 (gypsum+cement mixed material) achieved the highest pH values in the column tests consistently, also, Material_2 (gypsum+slag mixed material) and Material_3 (calcined limestone material) achieved over pH 9.0 for 240 hours (10 days) and proved the efficiencies of long-term ion supplier for HAP crystallization. In the column tests using Material_3, considerable pH increase and phosphorus removal were carried out according to each linear velocity and filtration depth. T-P removal efficiencies were 87.0, 84.0, 68.0% and those of PO4-P 100.0, 97.0, 80.0% for linear velocity of 1.0, 2.5, 5.0 m/hr respectively. Based on the column test results, the applicability of phosphorus removal processes for small-scale wastewater treatment plants and nonpoint pollution control facilities was found out.