The Experts below are selected from a list of 18705 Experts worldwide ranked by ideXlab platform
Ahmet Uygur - One of the best experts on this subject based on the ideXlab platform.
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specific Nutrient Removal rates in saline wastewater treatment using sequencing batch reactor
Process Biochemistry, 2006Co-Authors: Ahmet UygurAbstract:Abstract Effects of salt concentration (0–6%, w/v) on specific Nutrient Removal rates from saline wastewater in a sequencing batch reactor (SBR) were investigated. The sequencing batch operation consisted of anaerobic, oxic, anoxic and oxic phases with hydraulic residence times (HRT) of 1/3/1/1 h and a settling phase of 3/4 h. Solids retention time (SRT) was kept constant at 10 days in all experiments. Specific Nutrient (COD, NH 4 -N and PO 4 -P) Removal rates decreased with increasing salt concentration due to adverse effects of salt on microorganisms. A salt tolerant organism, Halobacter halobium was added to the activated sludge culture (1/1, v/v) in order to improve the Nutrient Removal performance of the SBR. Nutrient Removal performances of Halobacter -free and Halobacter -added activated sludge cultures were compared for all salt contents tested. Specific rates of Nutrient Removal obtained with the Halobacter -added culture were higher that those of Halobacter -free activated sludge, especially at high salt contents.
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Phenol inhibition of biological Nutrient Removal in a four-step sequencing batch reactor
Process Biochemistry, 2004Co-Authors: Ahmet Uygur, Fikret KargiAbstract:Nutrient Removal from synthetic wastewater was investigated using a four-step sequencing batch reactor (SBR) at different phenol (C 6 H 5 OH) concentrations in order to determine the inhibition effects of phenol on biological Nutrient Removal. The Nutrient Removal process consisted of anaerobic, oxic, anoxic, and oxic phases with hydraulic residence times (HRT) of 1 h/3 h/1 h/1 h and a settling phase of 3/4 h. Solids retention time (SRT) was kept constant at 10 days in all experiments. Initial phenol concentrations were varied between 0 and 600mg l - 1 at seven different levels. The effects of phenol on COD, NH 4 -N, and PO 4 -P Removals and effluent Nutrient levels were investigated. Phenol was almost completely degraded up to 400 mg l - 1 phenol concentration resulting in almost negligible inhibition effects on COD, NH 4 -N, and PO 4 -P Removals. Nutrient Removals were adversely affected by phenol at concentrations above 400mg l - 1 . Above 95% COD, 90% NH 4 -N and 65% PO 4 -P Removal was obtained for phenol concentrations below 400 mg l - 1 . The sludge volume index (SVI) was almost constant around 45 ml g - 1 for phenol concentrations below 400 mg l - 1 but increased to 90 ml g - 1 at a phenol level of 600 mg l - 1 .
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Nutrient Removal performance of a five step sequencing batch reactor as a function of wastewater composition
Process Biochemistry, 2003Co-Authors: Fikret Kargi, Ahmet UygurAbstract:Nutrient Removal from synthetic wastewater was studied as a function of Nutrient composition in a five-step sequencing batch reactor (SBR) in order to determine the most suitable Nutrient ratios maximizing Nutrient Removal. The Nutrient Removal process consisted of anaerobic, anoxic, oxic, anoxic, oxic phases. Hydraulic residence times (HRT) of the aforementioned phases were kept constant at 2/1/4.5/1.5/1.5 h with 1/2 h of settling phase. Solids retention time (SRT) was constant at 10 days in all experiments. COD/N and COD/P ratios in the Nutrient medium were considered as independent variables with a constant initial chemical oxygen demand (COD) of 1200 mg l−1. Box–Wilson statistical experiment design was used to determine the effects of independent variables on COD, NH4-N, and PO4-P Removal efficiencies. The results were correlated by a response function and the coefficients determined by regression analysis. COD/N/P ratio resulting in maximum COD, NH4-N and PO4-P Removal efficiencies was found to be 100/2/0.54 yielding COD, NH4-N and PO4-P Removal efficiencies of 95, 94 and 99%, respectively.
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Nutrient Removal performance of a sequencing batch reactor as a function of the sludge age
Enzyme and Microbial Technology, 2002Co-Authors: Fikret Kargi, Ahmet UygurAbstract:Abstract Nutrient Removal from synthetic wastewater by sequencing batch operation was studied at different solids retention times (SRTs). The Nutrient Removal process was consisted of anaerobic, anoxic I, oxic I, anoxic II, oxic II and settling phases. Hydraulic residence times (HRT) of the aforementioned phases were kept constant at 2/1/4.5/1.5/1.5 h. Settling phase was 0.5 h for all experiments. Solids retention time was varied between 5 and 30 days at six different levels. Effects of SRT (sludge age) on COD, nitrogen (NH4–N, NO3–N) and phosphate (PO4–P) Removal were investigated and the optimal sludge age resulting in maximum Nutrient Removal efficiency was determined. The highest COD (94%), NH4–N (84%) and PO4–P (70%) Removal efficiencies were obtained at the sludge age of 10 days, although a sludge age of 15 days resulted in only slightly lower values. Sludge ages larger than 15 days resulted in lower Nutrient Removal efficiencies as compared to those obtained at 10 or 15 days of sludge age. Sludge volume index (SVI) was also minimum (55 ml/g) at sludge age of 10 days. MLSS concentration increased with sludge age resulting in MLSS concentration of 3500 mg/l at SRT of 30 days. On the basis of these results, a sludge age of 10 days was found to be optimal resulting in maximum Nutrient Removal efficiencies and minimum SVI.
Fikret Kargi - One of the best experts on this subject based on the ideXlab platform.
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salt inhibition on biological Nutrient Removal from saline wastewater in a sequencing batch reactor
Enzyme and Microbial Technology, 2004Co-Authors: Ahme Uygu, Fikret KargiAbstract:Abstract Nutrient Removal from synthetic wastewater was investigated using a four-step sequencing batch reactor (SBR) at different salt (NaCl) concentrations in order to determine the salt inhibition effects on biological Nutrient Removal. The Nutrient Removal process consisted of anaerobic, oxic, anoxic and oxic phases with hydraulic residence times (HRT) of 1/3/1/1 h and a settling phase of 3/4 h. Solid retention time (SRT) was kept constant at 10 days in all experiments. Salt content was varied between 0 and 6% (w/v) at eight different levels. Effects of salt inhibition on the rate and extent of COD, NH4-N and PO4-P Removals were investigated. The rate and extent of COD, NH4-N and PO4-P Removals decreased while the effluent Nutrient concentrations and the sludge volume index (SVI) increased with increasing salt content.
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Phenol inhibition of biological Nutrient Removal in a four-step sequencing batch reactor
Process Biochemistry, 2004Co-Authors: Ahmet Uygur, Fikret KargiAbstract:Nutrient Removal from synthetic wastewater was investigated using a four-step sequencing batch reactor (SBR) at different phenol (C 6 H 5 OH) concentrations in order to determine the inhibition effects of phenol on biological Nutrient Removal. The Nutrient Removal process consisted of anaerobic, oxic, anoxic, and oxic phases with hydraulic residence times (HRT) of 1 h/3 h/1 h/1 h and a settling phase of 3/4 h. Solids retention time (SRT) was kept constant at 10 days in all experiments. Initial phenol concentrations were varied between 0 and 600mg l - 1 at seven different levels. The effects of phenol on COD, NH 4 -N, and PO 4 -P Removals and effluent Nutrient levels were investigated. Phenol was almost completely degraded up to 400 mg l - 1 phenol concentration resulting in almost negligible inhibition effects on COD, NH 4 -N, and PO 4 -P Removals. Nutrient Removals were adversely affected by phenol at concentrations above 400mg l - 1 . Above 95% COD, 90% NH 4 -N and 65% PO 4 -P Removal was obtained for phenol concentrations below 400 mg l - 1 . The sludge volume index (SVI) was almost constant around 45 ml g - 1 for phenol concentrations below 400 mg l - 1 but increased to 90 ml g - 1 at a phenol level of 600 mg l - 1 .
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Nutrient Removal performance of a five step sequencing batch reactor as a function of wastewater composition
Process Biochemistry, 2003Co-Authors: Fikret Kargi, Ahmet UygurAbstract:Nutrient Removal from synthetic wastewater was studied as a function of Nutrient composition in a five-step sequencing batch reactor (SBR) in order to determine the most suitable Nutrient ratios maximizing Nutrient Removal. The Nutrient Removal process consisted of anaerobic, anoxic, oxic, anoxic, oxic phases. Hydraulic residence times (HRT) of the aforementioned phases were kept constant at 2/1/4.5/1.5/1.5 h with 1/2 h of settling phase. Solids retention time (SRT) was constant at 10 days in all experiments. COD/N and COD/P ratios in the Nutrient medium were considered as independent variables with a constant initial chemical oxygen demand (COD) of 1200 mg l−1. Box–Wilson statistical experiment design was used to determine the effects of independent variables on COD, NH4-N, and PO4-P Removal efficiencies. The results were correlated by a response function and the coefficients determined by regression analysis. COD/N/P ratio resulting in maximum COD, NH4-N and PO4-P Removal efficiencies was found to be 100/2/0.54 yielding COD, NH4-N and PO4-P Removal efficiencies of 95, 94 and 99%, respectively.
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Nutrient Removal performance of a sequencing batch reactor as a function of the sludge age
Enzyme and Microbial Technology, 2002Co-Authors: Fikret Kargi, Ahmet UygurAbstract:Abstract Nutrient Removal from synthetic wastewater by sequencing batch operation was studied at different solids retention times (SRTs). The Nutrient Removal process was consisted of anaerobic, anoxic I, oxic I, anoxic II, oxic II and settling phases. Hydraulic residence times (HRT) of the aforementioned phases were kept constant at 2/1/4.5/1.5/1.5 h. Settling phase was 0.5 h for all experiments. Solids retention time was varied between 5 and 30 days at six different levels. Effects of SRT (sludge age) on COD, nitrogen (NH4–N, NO3–N) and phosphate (PO4–P) Removal were investigated and the optimal sludge age resulting in maximum Nutrient Removal efficiency was determined. The highest COD (94%), NH4–N (84%) and PO4–P (70%) Removal efficiencies were obtained at the sludge age of 10 days, although a sludge age of 15 days resulted in only slightly lower values. Sludge ages larger than 15 days resulted in lower Nutrient Removal efficiencies as compared to those obtained at 10 or 15 days of sludge age. Sludge volume index (SVI) was also minimum (55 ml/g) at sludge age of 10 days. MLSS concentration increased with sludge age resulting in MLSS concentration of 3500 mg/l at SRT of 30 days. On the basis of these results, a sludge age of 10 days was found to be optimal resulting in maximum Nutrient Removal efficiencies and minimum SVI.
David Steer - One of the best experts on this subject based on the ideXlab platform.
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the interacting effects of temperature and plant community type on Nutrient Removal in wetland microcosms
Bioresource Technology, 2005Co-Authors: Christian R Picard, Lauchlan H Fraser, David SteerAbstract:Treatment wetlands can remove Nutrients from inflow sources through biogeochemical processes. Plant composition and temperature play important roles in the Nutrient Removal efficiency of these wetlands, but the interactions between these variables are not well understood. We investigated the seasonal efficiency of wetland macrophytes to reduce soil leachate concentrations of total nitrogen and total phosphorus in experimental microcosms. Each microcosm contained one of six vegetation treatments: unplanted, planted with one of four species (Carex lacustris, Scirpus validus, Phalaris arundinacea and Typha latifolid) in monoculture or planted with an equal abundance of all four species. Microcosms were also subjected to two temperature treatments: insulated microcosms and microcosms exposed to environmental conditions. A constant Nutrient solution containing 56 mg/l N and 31 mg/l P was added to all microcosms three times a week. Water samples were analyzed monthly for total dissolved nitrogen and total dissolved phosphorous. Microcosms exhibited a typical pattern of seasonal Nutrient Removal with higher Removal rates in the growing season and lower rates in the winter months. In general, planted microcosms outperformed unplanted microcosms. Among the plant treatments, Carex lacustris was the least efficient. The four remaining plant treatments removed an equivalent amount of Nutrients. Insulated microcosms were more efficient in the winter and early spring months. Although a seasonal pattern of Nutrient Removal was observed, this variation can be minimized through planting and insulation of wetlands.
Azianabiha Halip A Khalid - One of the best experts on this subject based on the ideXlab platform.
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analysis of the elemental composition and uptake mechanism of chlorella sorokiniana for Nutrient Removal in agricultural wastewater under optimized response surface methodology rsm conditions
Journal of Cleaner Production, 2019Co-Authors: Azianabiha Halip A Khalid, Zahira Yaakob, Siti Rozaimah Sheikh Abdullah, Mohd Sobri TakriffAbstract:Abstract Microalgae exhibit large potential as an alternative to advanced biological Nutrient Removal in wastewater, but treatment efficiency is greatly influenced by process variables. Therefore, it is necessary to determine the optimum operating conditions for Nutrient Removal. In this study, Chlorella sorokiniana was used to remove ammonium (NH₄⁺) and phosphate (PO₄³⁻) from palm oil mill effluent. Response surface methodology (RSM) was employed to evaluate the interactions of three main influential factors, i.e., light intensity, photoperiod and inoculum size, and their effects on Nutrient Removal efficiency. The Nutrient preference, biomass elemental composition and Nutrient Removal mechanism of the microalgae were also investigated. Under the optimum conditions (200 μmol photon m⁻2s⁻1 12 h photoperiod and 28% inoculum size), 93.36% of NH₄⁺ and 94.50% of PO₄³⁻ were successfully removed. The microalgae were found to adjust their internal composition in response to the external concentration. Biomass N and P increased from 6.16 to 8.68% and from 1.0 to 2.21%, respectively. The microalgae preferred NH₄⁺ over organic N, and the Removal mechanisms involved not only assimilation for growth but also over-uptake for cellular storage. These findings are highly beneficial for maximizing the Nutrient Removal potential of microalgae in agricultural wastewater.
Zhang He Chen - One of the best experts on this subject based on the ideXlab platform.
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radial oxygen loss photosynthesis and Nutrient Removal of 35 wetland plants
Ecological Engineering, 2012Co-Authors: Yang Zhang, Zhang He ChenAbstract:Abstract The aim of the present study was to test the correlation between radial oxygen loss (ROL), photosynthesis, and Nutrient Removal based on the hypothesis that ROL was principally a positive physiological process of wetland plants, and was correlated with photosynthesis and Nutrient Removal. Thirty five emergent wetland plants were used for the measurement of ROL, photosynthesis, and Nutrient Removal in micro-scale wetlands in a climate chamber. Significant differences among thirty five species were tested in ROL, photosynthetic rate, and Nutrient Removal rates. ROL was positively correlated with photosynthetic rate ( P = 0.000), transpiration rate ( P = 0.005), root activity ( P = 0.000), root biomass of D ≤ 1 mm ( P = 0.002), above-ground biomass ( P = 0.030), leaf biomass ( P = 0.023), root porosity ( P = 0.000), maximum root length ( P = 0.011), and Removal rates of TN and TP ( P = 0.000, 0.002), while negatively related to root biomass of D ≥ 3 mm, and root longevity ( P = 0.022, 0.007). All the indices which were positively correlated with ROL, also positively correlated with plant growth. The results suggest that ROL may be an active physiological process or at least involves physiological processes of wetland plants. Significant differences existed among different wetland plants in ROL, photosynthesis, and Nutrient Removal, which should be considered in plant selection for constructed wetlands.
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Plant growth, community structure, and Nutrient Removal in monoculture and mixed constructed wetlands
Ecological Engineering, 2011Co-Authors: Ming-qiu Liang, Cheng-feng Zhang, Chang-lian Peng, Zeng-long Lai, Da-feng Chen, Zhang He ChenAbstract:Abstract The aim of this study was to compare the growth, community structure, and Nutrient Removal rates between monoculture and mixed wetlands, based on the hypothesis that it depends on the plant species used in the wetlands as to whether monoculture or mixed wetland is superior in plant growth and Nutrient Removal. Pilot-scale monoculture and mixed constructed wetlands were studied over 4 years. The monoculture wetland had a community height similar to the mixed wetland during the early years but a significantly lower height than the mixed wetland (P
