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Youngchul Kim - One of the best experts on this subject based on the ideXlab platform.
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evaluation of nitrogen reduction in water hyacinth Ponds integrated with Waste Stabilization Ponds
Desalination, 2009Co-Authors: Youngchul Kim, Masafumi TatedaAbstract:Abstract In this paper, a combined aquatic treatment process coupling Waste Stabilization Ponds (WSPs) with water hyacinth Ponds (WHPs) was investigated as means to upgrade secondary effluent from a Waste water treatment plant (WWTP). Naturally-occurring nitrification and denitrification phenomena were monitored and evaluated on a quantitative basis. The WSP supplied oxygen to the post process WHP, while the inside of the WHP provided a unique denitrification environment caused by respiration and biodegradation of the algae separated by hyacinth plant roots. The nitrification and denitrification rates were 0.04 and 0.02 g/kg day at 20 °C (wet weight basis), respectively, and were strongly affected by seasonal change. The temperature-dependent coefficients Θ were 1.06, which were approximately similar to frequently reported values from other biological nitrogen removal studies. Nitrification and denitrification were expected to occur as the water temperature was maintained between 20° to 30 °C. As plant density increased, their rates were also enhanced. Alkalinity balance corresponded fairly well with nitrogen behaviour during most of the operational period. Oxygen balance test results validated that the water hyacinth was crucial not only for separating algal particles from the WSP, but also for biological nitrogen reduction.
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modeling nitrogen removal in water hyacinth Ponds receiving effluent from Waste Stabilization Ponds
Ecological Engineering, 2009Co-Authors: Chinhyu Hur, Youngchul KimAbstract:Abstract We developed a dynamic model to predict nitrogen removal in water hyacinth Ponds (WHPs) receiving effluent from Waste Stabilization Ponds (WSPs). The model is based on the biofilm reaction on the root surface of plant and pond walls. The model consists of mass balances of six main substrates including: particulate organic nitrogen (PON), dissolved organic nitrogen (DON), ammonium (NH 4 + ), nitrite and nitrate (NOx), soluble chemical oxygen demand (SCOD), and particulate chemical oxygen demand (PCOD). The model, incorporating major nitrogen transformation mechanisms such as hydrolysis, mineralization, and nitrification–denitrification, accounts also for carbon consumption and plant uptake. The model's application to a pilot plant showed good agreement between measured and predicted values. According to the modeling results, in the WHPs, nitrification and denitrification were the predominant nitrogen removal processes occurring simultaneously. Temperature and hydraulic retention time (HRT) had a profound effect on the performance of nitrogen removal while an algae biomass (PCOD) accumulated in the WHPs, was a useful carbon source for denitrification.
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design of water hyacinth Ponds for removing algal particles from Waste Stabilization Ponds
Water Science and Technology, 2004Co-Authors: Youngchul Kim, Dimosthenis L Giokas, P G Chung, D R LeeAbstract:In this study it was demonstrated that when water hyacinth Ponds (WHPs) are used for polishing the effluent from Waste Stabilization Ponds (WSPs), suspended solids (mostly algal particles) are efficiently separated, which also resulted in the reduction of insoluble forms of COD and nutrients. The high pH of the WSPs effluent was easily adjusted to 6-7 as it passed through the WHPs. However, the use of water hyacinth rapidly reduced dissolved oxygen at the first cell to less than three mg/L or very frequently to a level of anaerobic state. Reduction of suspended solids at the WHPs mainly depends on the detention time and pH. An empirical separation model incorporating the detention time and pH dependence was developed.
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performance evaluation and mathematical modeling of nitrogen reduction in Waste Stabilization Ponds in conjunction with other treatment systems
Journal of Environmental Science and Health Part A-toxic\ hazardous Substances & Environmental Engineering, 2004Co-Authors: Youngchul Kim, Dimosthenis L Giokas, Jaehong Park, Triantafyllos A AlbanisAbstract:Abstract In this study, a widely-recognized nitrogen reduction model of Waste Stabilization Ponds (WSPs) was tested for its universal utility in four different cases including shallow algal Ponds (SAPs), WSPs followed by SAPs and water hyacinth Ponds, respectively, and WSPs upgrading a secondary effluent. A goodness-of-fit study between measurements and calculated values indicates that it provides a satisfactory description of nitrogen reduction for all three cases except the WSPs treating the effluent from SAPs. This is due to the inherent structure of the model underestimating an effect of pH and hydraulic residence time for Ponds system operated in series. However, when original model equation was modified as a form having a linear-relationship between reduction rate constant and pH values, it showed much better ability to reflect the process effluent. Finally, all the measured and calculated values were plotted to assess the overall performance of both models. Again, these results support an universal...
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roles of water hyacinths and their roots for reducing algal concentration in the effluent from Waste Stabilization Ponds
Water Research, 2000Co-Authors: Youngchul Kim, Wanjoong KimAbstract:Abstract This paper deals with use of water hyacinth and its root mats for controlling algal concentrations in the effluent from Waste Stabilization Ponds (WSPs). Pilot-scale integrated processes coupled WSPs with multiple WHPs (water hyacinth Ponds) were operated in order to determine the effects of the plant and root mats on reduction of algal concentrations on a quantitative basis. As flows from WSPs passed through the WHPs, root mats in the bottom as well as leaves and stems on the water surface of WHPs separated and controlled significant amount of algal cells by various mechanisms such as attachment, settling, respiration and suppression of algal growth. Attachment of algal particles to the plant roots was very similar to adsorption processes; i.e. there is a maximum capacity in a given weight of roots. However, effluent algal concentrations did not increase at saturation probably because of the sloughing-off of attached particles as a clump from the roots and generation of new attachment sites due to the growth of roots. Additionally, this paper discusses attachment forces and other issues concerning polishing of the WSPs effluent by WHPs.
Rob Jamieson - One of the best experts on this subject based on the ideXlab platform.
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predicting microalgae growth and phosphorus removal in cold region Waste Stabilization Ponds using a stochastic modelling approach
Environmental Science and Pollution Research, 2018Co-Authors: Jordan J Schmidt, Graham A Gagnon, Rob JamiesonAbstract:A stochastic ecological model with an integrated equilibrium temperature model was developed to predict microalgae growth and phosphorus removal in cold region Waste Stabilization Ponds (WSPs). The model utilized a Monte Carlo simulation to account for parameter uncertainty. The equilibrium temperature model was parameterized using field data collected from two WSPs in Nunavut, Canada, from 2012 to 2014. The equilibrium temperature model provided good agreement with field data on a daily time step. The full model was run using historic (1956–2005) temperature and solar radiation data from five communities (Baker Lake, Cambridge Bay, Coral Harbour, Hall Beach, Resolute) in Nunavut, Canada. The communities represented a range of geographical locations and environmental conditions. Logistic regression on pooled model outputs showed that mean July temperature and mean treatment season temperature (June 1–September 15, ice-free period) provided the best predictors for microalgae growth. They had a predictive success rate of 93 and 88%, respectively. The modelled threshold (50% probability from the Monte Carlo simulation) for microalgae growth was 8.7 and 5.6 °C for the July temperature and mean treatment season temperature, respectively. The logistic regression was applied to each community (except Sanikiluaq) in Nunavut using historic climate data and a probability of microalgae growth was calculated. Based on the model results, soluble phosphorus concentrations consistent with secondary treatment could be achieved if WSP depth is less than 2 m. The model demonstrated a robust method to predict whether a microalgae bloom will occur under a range of model parameters.
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characterizing phosphorus removal in passive Waste Stabilization Ponds in arctic communities
Arctic Science, 2016Co-Authors: Jordan J Schmidt, Colin M Ragush, Wendy H Krkosek, Graham A Gagnon, Rob JamiesonAbstract:A majority of communities in the Canadian territory of Nunavut rely on passive Waste Stabilization Ponds (WSPs) for domestic Wastewater treatment. Little research has been conducted on the treatment performance of these systems. Therefore, in response to impending federal Wastewater regulations, a research program was conducted in order to characterize contaminant removal, with phosphorus a contaminant of particular concern. The performance of WSPs in the Arctic communities of Kugaaruk, Pond Inlet, Grise Fiord, and Clyde River was evaluated from 2011 to 2014. Removal of total phosphorus was highly variable, ranging from 24% (Pond Inlet, 2014) to 76% (Grise Fiord, 2011). The average removal efficiency was 44%. Effluent total phosphorus concentrations generally exceeded 7 mg P/L, partly due to elevated raw Wastewater concentrations. Over the course of the treatment season (defined as June to September, when the WSP is thawed), limited additional total phosphorus removal was observed. A fractionation analysi...
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Performance of municipal Waste Stabilization Ponds in the Canadian Arctic
Ecological Engineering, 2015Co-Authors: Colin M Ragush, Jordan J Schmidt, Wendy H Krkosek, Graham A Gagnon, Lisbeth Truelstrup-hansen, Rob JamiesonAbstract:Abstract The majority of small remote communities in the Canadian arctic territory of Nunavut utilize Waste Stabilization Ponds (WSPs) for municipal Wastewater treatment because of their relatively low capital and operational costs, and minimal complexity. New national effluent quality regulations have been implemented in Canada, but not yet applied to Canada's Arctic due to uncertainty related to the performance of current Wastewater treatment systems. Waste Stabilization pond (WSP) treatment performance is impacted by community water use, pond design, and climate. The greatest challenge arctic communities experience when using passive Wastewater treatment technologies is the constraints imposed by the extreme climate, which is characterized as having long cold winters with short cool summers that can be solar intense. The removal of carbonaceous biochemical oxygen demand (CBOD 5 ), total suspended solids (TSS), and ammonia-nitrogen were measured during the summer treatment period (late June until early September) from 2011 to 2014 in the WSP systems of four Nunavut communities; Pond Inlet, Clyde River, Grise Fiord and Kugaaruk. Monitoring results showed that WSPs in their current single cell design can achieve greater than 80% removal of CBOD 5 and TSS but were challenged to produce effluent quality that meets secondary Wastewater treatment standards ( 5 and TSS). This study points to the need for revisions of design guidelines for facultative WSPs in the Arctic, as current systems are anaerobic and do not contain sufficient dissolved oxygen required to consistently support aerobic biological treatment processes.
Masafumi Tateda - One of the best experts on this subject based on the ideXlab platform.
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evaluation of nitrogen reduction in water hyacinth Ponds integrated with Waste Stabilization Ponds
Desalination, 2009Co-Authors: Youngchul Kim, Masafumi TatedaAbstract:Abstract In this paper, a combined aquatic treatment process coupling Waste Stabilization Ponds (WSPs) with water hyacinth Ponds (WHPs) was investigated as means to upgrade secondary effluent from a Waste water treatment plant (WWTP). Naturally-occurring nitrification and denitrification phenomena were monitored and evaluated on a quantitative basis. The WSP supplied oxygen to the post process WHP, while the inside of the WHP provided a unique denitrification environment caused by respiration and biodegradation of the algae separated by hyacinth plant roots. The nitrification and denitrification rates were 0.04 and 0.02 g/kg day at 20 °C (wet weight basis), respectively, and were strongly affected by seasonal change. The temperature-dependent coefficients Θ were 1.06, which were approximately similar to frequently reported values from other biological nitrogen removal studies. Nitrification and denitrification were expected to occur as the water temperature was maintained between 20° to 30 °C. As plant density increased, their rates were also enhanced. Alkalinity balance corresponded fairly well with nitrogen behaviour during most of the operational period. Oxygen balance test results validated that the water hyacinth was crucial not only for separating algal particles from the WSP, but also for biological nitrogen reduction.
Sven Erik Jorgensen - One of the best experts on this subject based on the ideXlab platform.
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diurnal cycles of variation of physical chemical parameters in Waste Stabilization Ponds
Ecological Engineering, 2002Co-Authors: S. Kayombo, T.s.a. Mbwette, J. H. Y. Katima, A W Mayo, Sven Erik JorgensenAbstract:Abstract Diurnal fluctuations of pH, dissolved oxygen (DO), water, air temperature and sunlight intensity were investigated in the Waste Stabilization Ponds at the University of Dar es Salaam. The variation of these parameters followed the diurnal pattern of light intensity. The rate of oxygen production based on first order linear regression analysis was between 0.02 and 0.36 mg/l per h with high production rate being observed in secondary facultative Ponds. The rate of utilization of dissolved oxygen (total respiration) during the night by the microbial population in the pond ranged between 0.016 and 0.435 mg/l per h. The average rate of increase of pH during the day was 0.0006–0.243 units of pH per h, and the rate of decrease was 0.0003–0.101 units of pH per h. The Ponds receiving low organic loading showed high diurnal variation of physical–chemical parameters. The relationship between average hourly DO and pH followed a polynomial trend with the coefficient of regression (R2) ranging from 0.76 to 0.82. It may be concluded that the diurnal variation of the parameters in the WSPs is due to hourly and daily variation of light intensity.
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modelling diurnal variation of dissolved oxygen in Waste Stabilization Ponds
Ecological Modelling, 2000Co-Authors: S. Kayombo, T.s.a. Mbwette, J. H. Y. Katima, A W Mayo, Sven Erik JorgensenAbstract:Abstract The dissolved oxygen sub model was developed in order to depict the combined influence of light, pH, temperature and carbon dioxide on the processes of dissolved oxygen (DO) production and utilization in secondary facultative Waste Stabilization Ponds (SFWSP). The model was formulated based on Chen and Orlob (Chen, C.W., Orlob, G.T., 1975. In: Patten, B.C. (Ed.), Systems Analysis in Ecology, Vol. 3. Academic Press, New York, pp. 476–588.), and was modified to include the influence of pH and carbon dioxide. The forcing functions to the DO model were light intensity, carbon dioxide, temperature and pH. It was found that temperature, light and pH influence the process of photosynthesis based on the multiplicative formulation of forcing functions. The model was calibrated and validated by using the average daily data from SFWSP1 and 11. The model yielded a linear regression coefficient of 0.87 during calibration and 0.78 during validation. Based on the model results the rate of production of DO with relation to dry algal biomass was 1.599 mg DO/mg dry weight, which is equivalent to 35.905 mg DO/mg chlorophyll-a. Such correlation between the observed data and model prediction indicates that the assumption inherent in the mathematical model formulation of the processes is valid for the description of DO production and usage in the Ponds.
Jordan J Schmidt - One of the best experts on this subject based on the ideXlab platform.
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predicting microalgae growth and phosphorus removal in cold region Waste Stabilization Ponds using a stochastic modelling approach
Environmental Science and Pollution Research, 2018Co-Authors: Jordan J Schmidt, Graham A Gagnon, Rob JamiesonAbstract:A stochastic ecological model with an integrated equilibrium temperature model was developed to predict microalgae growth and phosphorus removal in cold region Waste Stabilization Ponds (WSPs). The model utilized a Monte Carlo simulation to account for parameter uncertainty. The equilibrium temperature model was parameterized using field data collected from two WSPs in Nunavut, Canada, from 2012 to 2014. The equilibrium temperature model provided good agreement with field data on a daily time step. The full model was run using historic (1956–2005) temperature and solar radiation data from five communities (Baker Lake, Cambridge Bay, Coral Harbour, Hall Beach, Resolute) in Nunavut, Canada. The communities represented a range of geographical locations and environmental conditions. Logistic regression on pooled model outputs showed that mean July temperature and mean treatment season temperature (June 1–September 15, ice-free period) provided the best predictors for microalgae growth. They had a predictive success rate of 93 and 88%, respectively. The modelled threshold (50% probability from the Monte Carlo simulation) for microalgae growth was 8.7 and 5.6 °C for the July temperature and mean treatment season temperature, respectively. The logistic regression was applied to each community (except Sanikiluaq) in Nunavut using historic climate data and a probability of microalgae growth was calculated. Based on the model results, soluble phosphorus concentrations consistent with secondary treatment could be achieved if WSP depth is less than 2 m. The model demonstrated a robust method to predict whether a microalgae bloom will occur under a range of model parameters.
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characterizing phosphorus removal in passive Waste Stabilization Ponds in arctic communities
Arctic Science, 2016Co-Authors: Jordan J Schmidt, Colin M Ragush, Wendy H Krkosek, Graham A Gagnon, Rob JamiesonAbstract:A majority of communities in the Canadian territory of Nunavut rely on passive Waste Stabilization Ponds (WSPs) for domestic Wastewater treatment. Little research has been conducted on the treatment performance of these systems. Therefore, in response to impending federal Wastewater regulations, a research program was conducted in order to characterize contaminant removal, with phosphorus a contaminant of particular concern. The performance of WSPs in the Arctic communities of Kugaaruk, Pond Inlet, Grise Fiord, and Clyde River was evaluated from 2011 to 2014. Removal of total phosphorus was highly variable, ranging from 24% (Pond Inlet, 2014) to 76% (Grise Fiord, 2011). The average removal efficiency was 44%. Effluent total phosphorus concentrations generally exceeded 7 mg P/L, partly due to elevated raw Wastewater concentrations. Over the course of the treatment season (defined as June to September, when the WSP is thawed), limited additional total phosphorus removal was observed. A fractionation analysi...
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Performance of municipal Waste Stabilization Ponds in the Canadian Arctic
Ecological Engineering, 2015Co-Authors: Colin M Ragush, Jordan J Schmidt, Wendy H Krkosek, Graham A Gagnon, Lisbeth Truelstrup-hansen, Rob JamiesonAbstract:Abstract The majority of small remote communities in the Canadian arctic territory of Nunavut utilize Waste Stabilization Ponds (WSPs) for municipal Wastewater treatment because of their relatively low capital and operational costs, and minimal complexity. New national effluent quality regulations have been implemented in Canada, but not yet applied to Canada's Arctic due to uncertainty related to the performance of current Wastewater treatment systems. Waste Stabilization pond (WSP) treatment performance is impacted by community water use, pond design, and climate. The greatest challenge arctic communities experience when using passive Wastewater treatment technologies is the constraints imposed by the extreme climate, which is characterized as having long cold winters with short cool summers that can be solar intense. The removal of carbonaceous biochemical oxygen demand (CBOD 5 ), total suspended solids (TSS), and ammonia-nitrogen were measured during the summer treatment period (late June until early September) from 2011 to 2014 in the WSP systems of four Nunavut communities; Pond Inlet, Clyde River, Grise Fiord and Kugaaruk. Monitoring results showed that WSPs in their current single cell design can achieve greater than 80% removal of CBOD 5 and TSS but were challenged to produce effluent quality that meets secondary Wastewater treatment standards ( 5 and TSS). This study points to the need for revisions of design guidelines for facultative WSPs in the Arctic, as current systems are anaerobic and do not contain sufficient dissolved oxygen required to consistently support aerobic biological treatment processes.