Phosphorus Removal in Wastewater Using Activated Ca-Loess Complex

강성철,이병호 대한상하수도학회 2012 상하수도학회지 Vol.26 No.5

In many instances phosphorus is a limiting factor for eutrophication in streams, and lakes. Because wastewater treatment plant itself may be the main phosphorus source in a natural water body, removal of phosphorus in final effluent of wastewater treatment processes is required. Amongst various technologies for phosphorus removal in wastewater, adsorption technology was investigated using activated Ca-loess complex. Ca was added in loess to enhance adsorption capacity and intensity of phosphorus. Ca added loess was activated at a high temperature of 400oC which turned out to be the optimum temperature. Activated Ca-loess complex below 400oC had not enough strength to be applied as an activated Ca-loess pallet column in wastewater treatment process. Ca-loess complex which activated above 400oC lost its adsorption capacity as the loess surface was glassified when the activation temperature reached above 400oC. Even if adsorption capacity of activated Ca-loess was not very high due to the lack of abundant pores on its surface, adsorption intensity was still high because it was activated with added Ca in loess. Activated loess was made by pallets. The activated loess pallets were filled in a column, and were applied in wastewater treatment process. Using an activated Ca-loess pallet column, total phosphorus (T-P) was reduced from about 0.5mg/l to lower than 0.1mg/l in wastewater treatment, and ionic phosphorus (phosphate) was completely removed for the four months of pilot plant operation. In many instances phosphorus is a limiting factor for eutrophication in streams, and lakes. Because wastewater treatment plant itself may be the main phosphorus source in a natural water body, removal of phosphorus in final effluent of wastewater treatment processes is required. Amongst various technologies for phosphorus removal in wastewater, adsorption technology was investigated using activated Ca-loess complex. Ca was added in loess to enhance adsorption capacity and intensity of phosphorus. Ca added loess was activated at a high temperature of 400oC which turned out to be the optimum temperature. Activated Ca-loess complex below 400oC had not enough strength to be applied as an activated Ca-loess pallet column in wastewater treatment process. Ca-loess complex which activated above 400oC lost its adsorption capacity as the loess surface was glassified when the activation temperature reached above 400oC. Even if adsorption capacity of activated Ca-loess was not very high due to the lack of abundant pores on its surface, adsorption intensity was still high because it was activated with added Ca in loess. Activated loess was made by pallets. The activated loess pallets were filled in a column, and were applied in wastewater treatment process. Using an activated Ca-loess pallet column, total phosphorus (T-P) was reduced from about 0.5mg/l to lower than 0.1mg/l in wastewater treatment, and ionic phosphorus (phosphate) was completely removed for the four months of pilot plant operation.

The effect of phosphorus removal from sewage on the plankton community in a hypertrophic reservoir

정성민,김기용,이윤경,이재용,정유경,Arif Reza,김재구,OWENJEFFREY SCOTT,김범철 한국생태학회 2016 Journal of Ecology and Environment Vol.40 No.1

Background: When developing water quality improvement strategies for eutrophic lakes, questions may arise about the relative importance of point sources and nonpoint sources of phosphorus. For example, there is some skepticism regarding the effectiveness of partial reductions in phosphorus loading; because phosphorus concentrations are too high in hypertrophic lakes, in-lake phosphorus concentrations might still remain within typical range for eutrophic lakes even after the reduction of phosphorus loading. For this study, water quality and the phytoplankton and zooplankton communities were monitored in a hypertrophic reservoir (Lake Wangsong) before and after the reduction of phosphorus loading from a point source (a sewage treatment plant) by the installation of a chemical phosphorus-removal process. Results: Before phosphorus removal, Lake Wangsong was classified as hypertrophic with a median phosphorus concentration of 0.232 mg L−1 and a median chlorophyll-a concentration of 112 mg L−1. The dominant phytoplankton were filamentous cyanobacteria for the most of the ice-free season. Following the installation of the advanced treatment process, phosphorus concentrations were reduced to 81 mg L−1, and the N/P atomic ratio increased from 42 to 102. Chlorophyll-a concentrations decreased to 42 μg L−1, and the duration of cyanobacterial dominance was confined to the summer season. Cyanobacteria in spring and autumn were replaced by diatoms and cryptomonads. Filamentous cyanobacteria in summer were replaced by colony-forming unicellular Microcystis spp. It was remarkable that zooplankton biomass increased despite the decrease in phytoplankton biomass, and especially cladoceran zooplankton which increased drastically. These responses to the reduction of point source P loading to Lake Wangsong imply that reducing the point source P loading can have a big impact even when nonpoint sources account for a large fraction of the total annual phosphorus loading. Conclusions: Our results also show that the phytoplankton community can shift to decreased cyanobacterial dominance and the zooplankton community can shift to higher cladoceran dominance, even when phosphorus concentrations remain within the typical range for eutrophic lakes following the reduction of phosphorus loading.

The effect of phosphorus removal from sewage on the plankton community in a hypertrophic reservoir

Jung, Sungmin,Kim, Kiyong,Lee, Yunkyoung,Lee, Jaeyong,Cheong, Yukyong,Reza, Arif,Kim, Jaiku,Owen, Jeffrey S.,Kim, Bomchul The Ecological Society of Korea 2016 Journal of Ecology and Environment Vol.40 No.1

Background: When developing water quality improvement strategies for eutrophic lakes, questions may arise about the relative importance of point sources and nonpoint sources of phosphorus. For example, there is some skepticism regarding the effectiveness of partial reductions in phosphorus loading; because phosphorus concentrations are too high in hypertrophic lakes, in-lake phosphorus concentrations might still remain within typical range for eutrophic lakes even after the reduction of phosphorus loading. For this study, water quality and the phytoplankton and zooplankton communities were monitored in a hypertrophic reservoir (Lake Wangsong) before and after the reduction of phosphorus loading from a point source (a sewage treatment plant) by the installation of a chemical phosphorus-removal process. Results: Before phosphorus removal, Lake Wangsong was classified as hypertrophic with a median phosphorus concentration of $0.232mg\;L^{-1}$ and a median chlorophyll-a concentration of $112mg\;L^{-1}$. The dominant phytoplankton were filamentous cyanobacteria for the most of the ice-free season. Following the installation of the advanced treatment process, phosphorus concentrations were reduced to $81mg\;L^{-1}$, and the N/P atomic ratio increased from 42 to 102. Chlorophyll-a concentrations decreased to $42{\mu}g\;L^{-1}$, and the duration of cyanobacterial dominance was confined to the summer season. Cyanobacteria in spring and autumn were replaced by diatoms and cryptomonads. Filamentous cyanobacteria in summer were replaced by colony-forming unicellular Microcystis spp. It was remarkable that zooplankton biomass increased despite the decrease in phytoplankton biomass, and especially cladoceran zooplankton which increased drastically. These responses to the reduction of point source P loading to Lake Wangsong imply that reducing the point source P loading can have a big impact even when nonpoint sources account for a large fraction of the total annual phosphorus loading. Conclusions: Our results also show that the phytoplankton community can shift to decreased cyanobacterial dominance and the zooplankton community can shift to higher cladoceran dominance, even when phosphorus concentrations remain within the typical range for eutrophic lakes following the reduction of phosphorus loading.

하계 영산강, 하구호 및 하구 퇴적물 내 인의 생지화학적 특성

최재훈,안성욱,김성한,신재혁,이효진,현정호,목진숙 한국해양환경·에너지학회 2020 한국해양환경·에너지학회지 Vol.23 No.4

To understand the behavior of phosphorus in the sediment of the Yeongsan River (YR), Lake (YL) and Estuary (YE), we investigated the characteristics of geochemical constituents and solid phase phosphorus. A hypoxic condition was confirmed in the lake sediment near the dyke (YL, 10 μM), where, freshwater discharge had not occurred for the 15 days prior to sample collection, whereas the dissolved oxygen concentration at the estuarine site (YE) was relatively high (165 μM). The high values of NH4+ (65.7 mmol m-2) and Fe2+ (14.9 mmol m-2) was integrated in the pore water at the lake (YL). On the other hand, PO43- in pore water was relatively at least 4-8 times higher in the estuary sediment (YE). Phosphorus release rates were twice as high in the estuary (0.047 mmol m-2 d-1) as the lake (0.021 mmol m-2 d-1), while the total phosphorus in the sediment was higher in the lake (6,665 mmol m-2) and decreased rapidly in the estuary (1,000 mmol m-2). After analyzing the speciation of phosphorus in the sediment, aluminum bound phosphorus (YR: 66%, YL: 40%) and iron bound phosphorus (YR: 17%, YL: 30%) were dominant for the Yeongsan river and lake, whereas the estuary dominated iron (43%) and authigenic calcium bound phosphorus (29%). Although the lake was a hypoxic environment, phosphorus in the sediment combined with aluminum to maintain a relatively stable form, limiting the process of phosphorus separated into the pore water and released into the water layer. Whereas, the ratio of iron binding in the phosphorus form in the estuary was dominant, but shows the adsorption of phosphorus to iron oxide might be relatively limited because release of phosphorus to the pore water might occur during the bonding process of iron and hydrogen sulfide. These results suggest environmental changes (e.g., environment of hypoxic, supply of sulfate) due to the construction of estuary dikes can act as a major factor in controlling phosphorus behavior. 수층 내 인의 순환을 이해하는데 퇴적물 내에 인의 존재형태와 존재형태별 공급과 소비의 조절요인 규명이 중요한데 이들은 퇴적물 내 생지화학적인 환경특성과 밀접한 관계가 있다. 이 연구에서는 퇴적물 내 다양한 생지화학적인 특성을 가진 영산강(YR), 하구호(YL) 및 하구역(YE)에서 환경 요인 변화에 따른 인의 거동을 이해하기 위해 퇴적물의 지화학 성분 및 고형상 인의 형태별 분포 특성을 파악하였다. 하구호(YL, 10 μM)에서 빈산소 환경으로 공극수 내 누적된 NH4+(65.7 mmol m-2)와 Fe2+(14.9 mmol m-2)의 값이 높게 나타났다. PO43-는 하구역(YE) 정점의 공극수에서 4-8배 이상 높게 나타났다. 인 용출율 또한 하구호(0.021 mmol m-2 d-1)보다 하구역(0.047 mmol m-2 d-1)에서 2배 정도 높게 나타났다. 한편, 퇴적물 내 누적된 총인의 값은 하구호(6,665 mmol m-2)에서 높고 하구역(1,000 mmol m-2)에서 급격히 감소하는 분포를 보였다. 퇴적물 내 인의 존재 형태를 분석한 결과, 영산강과 하구호에서 알루미늄 결합인(YR: 66%, YL: 40%)과 철 결합인(YR: 17%, YL: 30%)이 우세한 반면, 하구역의 경우 철 결합인(43%)과 자생성 칼슘 결합인(29%)이 우세하였다. 하구호는 빈산소 환경임에도 퇴적물 내 인이 알루미늄과 결합하여 비교적 안정한 형태를 유지함으로써, 인이 공극수 내로 분리되어 수층으로 용출되는 과정이 제한되었다. 반면, 하구역에서 인 형태 중 철 결합인의 비중은 우세하지만 철과 황화수소의 결합과정에서 공극수로의 인 배출이 일어날 수 있기 때문에 상대적으로 산화철에 대한 인의 흡착이 제한될 수 있음을 보여주었다. 이러한 결과는 하구둑 건설로 인한 환경변화(빈산소 형성, 황산염 공급 등)가 인의 거동을 조절하는 주요 인자로 작용할 수 있음을 제시하고 있다.

슬러지 가용화에 따른 인 방출 특성연구

이채영,한선기 대한상하수도학회 2022 상하수도학회지 Vol.36 No.6

The anaerobic digestion process produces methane while stabilizing sludge. As of 2020, 62 anaerobic digesters in public wastewater treatment plants are operational in Korea. Many researchers have studied to improve digester performance. Thermal hydrolysis technology is one of the pre-treatment methods for treating sludge. Reduced retention time and enhanced biogas production are the main advantages of sludge disintegration at relatively high temperatures and pressures. But nutrients like nitrogen and phosphorus are released from the pre-treatment of sludge. Phosphorus is a non-renewable resource that is essential to food production. Wastewater receives 20% of the total phosphate discharge, while 90% of the influent phosphorus load is in sludge. For efficient phosphorus recovery, it is essential to comprehend the phosphorus release characteristics during wastewater treatment, including anaerobic digestion. Biological or chemical processes can achieve phosphorus removal to comply with the effluent discharge limits regulations. The three primary sources of phosphorus in sludge are aluminum-bound phosphorus (Al-P), polyphosphate in phosphorus-accumulating organisms (PAOs), and iron-bound phosphorus (Fe-P). Anaerobic digestion is the typical method for recovering carbon and phosphorus. However, previous research has demonstrated that most phosphorus in anaerobic digestion occurs as a solid phase coupled with heavy metals. Therefore, the poor mass transfer rate results in a slow phosphorus release. Due to the recent growth in interest and significance of phosphorus recovery, many researchers have studied to improve the quantity of phosphorus released into the liquid phase through chelation addition, process operation optimization, and disintegration using sludge pre-treatment. The study aims to investigate characteristics of the phosphorus release associated with the thermal hydrolysis breakdown of sludge and propose a method for recovering phosphorus in a wastewater treatment plant. When solubilizing sludge using thermal hydrolysis pre-treatment, organic phosphates, inorganic phosphates, and polyphosphates are converted into ortho-phosphate. Therefore, applying thermal hydrolysis, anaerobic digestion, and phosphorus recovery processes (struvite formation or microbial electrolysis cells) can recover carbon and phosphorus.

순차적 혐기-호기 전환법에 의한 남조류 Synechococcus sp.의 생물학적 인 제거 가능성 평가

유미영,박종진,황선진 한국폐기물자원순환학회 2019 한국폐기물자원순환학회지 Vol.36 No.8

The A2O process, which is used to treat most of the wastewater generated in Korea, induces the luxury uptake ofphosphorus-accumulating organisms (PAO) through anaerobic-aerobic conversion. Moreover, it can remove phosphorusby wasting microorganisms containing large amounts of phosphorus. However, when the nitrate in the return sludge entersthe anaerobic tank, the diminished reducing power of the anaerobic tank inhibits phosphorus release, which limits thephosphorus removal efficiency. In this study, the possibility of enhanced phosphorus removal is explored under theanaerobic-aerobic method by using the cyanobacterium Synechococcus sp., which can synthesize polyhydroxybutyrate(PHB) like PAO. If Synechococcus sp. can remove excess phosphorus according to the same mechanism as PAO, it canpossibly have a synergistic effect on phosphorus removal through photosynthesis metabolism as well as luxury-uptakedue to anaerobic-aerobic conversion. The study results indicate that there was no significant difference in growth andcarbon and phosphorus removal efficiencies, regardless of exposure to anaerobic conditions. Therefore, it the anaerobiccondition can be considered to not inhibit the growth and metabolism of Synechococcus sp. Under anaerobic conditions,Synechococcus sp. released 28 mg-P/g-MLSS/day of phosphorus, which is lower than the amount released by PAObacteria. There was no significant difference in the amounts of phosphorus removal between the anaerobic-aerobicconversion experiment and the control. In addition, the trend of carbon consumption was not consistent with the trendof phosphorus release. Therefore, at the very least, phosphorus release by Synechococcus sp. might follow a differentpathway, or Synechococcus sp. does not release phosphorus, unlike PAO. Therefore, according to the results of this study,the application of Synechococcus sp. for phosphorus removal, similarly to PAO bacteria, through the anaerobic-aerobicconversion method is inappropriate.

수돗물의 탄소와 인 농도에 따른 세균의 생장과 C/P 소모율

최성찬,박세근,김영관 대한상하수도학회 2013 상하수도학회지 Vol.27 No.6

Bacterial growth and corresponding consumption of carbon and phosphorus were examined in which tap water samples containing a very low concentration of free chlorine were supplemented with organic carbon and/or phosphorus. The experiments were performed in a fed-batch mode under a controlled temperature of 20℃. In the phosphorus alone-added water, there was no significant increase in bacterial numbers measured as heterotrophic plate count (HPC) in the bulk water. However, bacterial growth was stimulated by the addition of carbon (e.g., bulk HPC levels increased to 103 CFU/mL) and further stimulated by the combined addition of carbon and phosphorus (e.g., bulk HPC to 105 CFU/mL). The same effects were observed in biofilm HPC and biomass formed on polyethylene (PE) slide surfaces. In the water where organic carbon and phosphorus were added together, the highest biofilm HPC and biomass (measured as extracellular polymeric substance components) densities were observed which were 7.6×105 CFU/cm2 and 5.3 μg/cm2, respectively. In addition to the bacterial growth, additions of organic carbon and/or phosphorus resulted in different bacterial carbon-to-phosphorus (C/P) consumption ratios. Compared to a typical bacterial C/P consumption ratio of 100:1, a higher C/P ratio (590:1) occurred in the carbon alone-added water, while a lower ratio (40:1) in phosphorus alone-added water. Comparative value (80:1) of C/P ratio was also observed in the water where organic carbon and phosphorus were added together. At the given experimental conditions, bacterial growth was deemed to be more sensitive to microbially available organic carbon than phosphorus. The effect of phosphorus addition, which resulted in a lower C/P consumption ratio, seemed to be tightly associated with the presence of microbially available organic carbon. These results suggested that the control of extrinsic carbon influx seemed to be more important to minimize bacterial regrowth in drinking water system, since even low content of phosphorus naturally occurring in drinking water was enough to allow a bacterial growth

Secretion of acid phosphatase by the roots of crop plants under phosphorus-deficient conditions and some properties of the enzyme

TADANO, T,OZAWA, K,SAKAI,H,OSAKI, M,MATSUI, H 嶺南大學校 環境問題硏究所 1996 環境硏究 Vol.16 No.1

ABSTRACTThe purposes of this study are to clarify the behavior of phosphorus in coagulation/sedimentation process, and to evaluate the effects of phosphorus addition into biological activated carbon (BAC) treatment on the biodegradation of organic substances. Conventional coagulation/sedimentation reduced phosphorus concentration to very low level, that is, 0.002 - 0.004 mg P.1??-1 in water containing less than 0.063 mg P.1??-1. In continuous experiment, the biodegradation rate of glucose in the BAC with adsorbed phosphorus before the start of operation was 5 times higher than that in the BAC without adsorbed phosphorus. The rate of increase in bacterial population was higher in the BAC with adsorbed phosphorus compared to the BAC without adsorbed phosphorus. The biodegradation rate of glucose in the BAC without adsorbed phosphorus increased significantly by addition of phosphorus into influent. Therefore, growth and biodegradation activity of attached bacteria on BAC was limited by phosphorus of low concentration in influent treated by coagulation/sedimentation. Adsorption of phosphorus on activated carbon before the start of operation and/or addition of phosphorus in influent will be effective to improve the biological activity on BAC.

Optimization for Phosphorus Remove by Loess Ball Using Chromobacterium

최두복,이춘범,차월석,Choi Du Bok,Lee Choon-Boem,Cha Wol-Suk Korean Society of Life Science 2005 생명과학회지 Vol.15 No.4

담체인 황토볼와 Chromobacterium WS 2-14을 이용하여 F-STEP공정(혐기${\rightarrow}$ 호기${\rightarrow}$ 무산소)에서 실제폐수에 존재하는 인산을 효율적으로 제거하기 위해 최적 황토볼 크기 및 소성 온도, 폐수의 초기 pH,폐수의 초기 인산염 농도, 운전온도, 그리고 통기를 검토했다. 최적 조건은 다음과 같다. 황토볼 크기 및 소성 온도, $2\~4mm,\;960^{\circ}C$; 실페수의 초기pH, 6.0; 실페수의 초기 인산 농도, 5.0mg/1. 운전온도, $30^{\circ}C$; 그리고 통기, 5.0L/min등이 얻어졌다. 그리고 최적 운전조건을 이용해서 pilot test을 65일 동안 진행했다. 인산 평균 제거율은 $92.0\%$였고. 또한 최종 유출수에서 COD와 BOD의 평균 제거율은 각각 77.1와 $74.2\%$였으며, SS의 경우는 평균 제거율이, $86.4\%$였다. 이상의 결과로부터 황토볼을 담체로 이용한 Biofilter System은 실제폐수에 존재하는 인산 제거 가능성을 암시했다. To investigate factors affecting the removal of phosphorus from the practical wastewater in the F-STEP PROCESS using a loess ball and Chromobacterium WS 2-14, first, the loess ball size and calcining temperature, initial pH, initial phosphorus concentration, working temperature, and aeration were studied. A $2\~4mm$ of loess ball made at $960^{\circ}C$ of calcining temperature was the most suitable one for the removal of phosphorus. When the initial pH was increased from 3.0 to 6.0, the removal efficiency of phosphorus was increased. Especially, at 6.0 of initial pH, the maximum removal efficiency of phosphorus was $88.7\%$. The maximum removal efficiency of phosphorous was gained, 1.8mg/h when the initial concentration of phosphorous was 5.0mg/1. When the operating temperature was $30^{\circ}C$, the maximum removal efficiency of phosphorus was obtained. In the case of aeration, when it was increased from 0.5 to 5.0L/min, the removal efficiency of phosphorus was increased. On the other hand, above 7.0 L/min, the removal efficiency of phosphorus did not increased. Using the optimum operation conditions, pilot tests for the effective removal efficiency of phosphorus were carried out for 65 days. The average removal efficiency of phosphorus was $92.0\%$. The average removal efficiency of COD, BOD, and SS were 77.1, 74.2, and $86.4\%$, respectively. from the results, it can be concluded that F-STEP PROCESS using loess ball might be useful process for phosphorus removal.

아시아 몬순지역의 대형댐(소양호)에서의 인순환과 2차원모델의 적용

김범철 ( Bom Chul Kim ),김윤희 ( Yoon Hee Kim ) 한국하천호수학회 2004 생태와 환경 Vol.37 No.2

Phosphorus cycle was studied in a deep stratified reservoir in summer monsoon area (Lake Soyang, Korea) by surveying phosphorus input from the watershed and the movement of phosphorus within the reservoir. And the spatial and temporal distribution of phosphorus was modeled with a 2-dimensional water quality model (CE-QUAL-W2). Phosphorus loading was calculated by measuring TP in the main inflowing river (the Soyang River) accounting for 90% of watershed discharge. TP of the Soyang River showed a large daily variation with the flow rate. High phosphorus loading occurred during a few episodic storm runoff laden with suspended sediments and phosphorus. Because storm runoff water on rainy days have lower temperature, it plunges into a depth of same temperature (usually below 20m depth), forming an intermediate turbidity layer with a thickness of 20~30 m. Because of stable thermal stratification in summer the intermediate layer water of high phosphorus content was discharged from the dam through a mid-depth outlet without diffusing into epilimnion. The movement of runoff water within the reservoir, and the subsequent distribution of phosphorus were well simulated by the water quality model showing a good accuracy. The major parameter for the calibration of phosphorus cycle was a settling velocity of detritus, which was calibrated to be 0.75 m·day^(-1). It is concluded that the model can be a good simulator of limnological phenomena in reservoirs of summer monsoon area.