Demirer, Sibel
Loading...
Profile URL
Name Variants
Uludag-Demirer, Sibel
Uludag, Demirer S.
Uludag-Demirer, S.
Uludaǧ-Demirer, S.
Uludag-Demirer, S
Uludag, Demirer S.
Uludag-Demirer, S.
Uludaǧ-Demirer, S.
Uludag-Demirer, S
Job Title
Yrd. Doç. Dr.
Email Address
Main Affiliation
06.04. Endüstri Mühendisliği
Endüstri Mühendisliği
06. Mühendislik Fakültesi
01. Çankaya Üniversitesi
Endüstri Mühendisliği
06. Mühendislik Fakültesi
01. Çankaya Üniversitesi
Status
Former Staff
Website
ORCID ID
Scopus Author ID
Turkish CoHE Profile ID
Google Scholar ID
WoS Researcher ID
Sustainable Development Goals
11
SUSTAINABLE CITIES AND COMMUNITIES
1
Research Products
3
GOOD HEALTH AND WELL-BEING
0
Research Products
9
INDUSTRY, INNOVATION AND INFRASTRUCTURE
1
Research Products
6
CLEAN WATER AND SANITATION
3
Research Products
14
LIFE BELOW WATER
0
Research Products
12
RESPONSIBLE CONSUMPTION AND PRODUCTION
1
Research Products
8
DECENT WORK AND ECONOMIC GROWTH
1
Research Products
1
NO POVERTY
0
Research Products
4
QUALITY EDUCATION
0
Research Products
5
GENDER EQUALITY
0
Research Products
10
REDUCED INEQUALITIES
0
Research Products
16
PEACE, JUSTICE AND STRONG INSTITUTIONS
0
Research Products
15
LIFE ON LAND
0
Research Products
7
AFFORDABLE AND CLEAN ENERGY
0
Research Products
13
CLIMATE ACTION
0
Research Products
17
PARTNERSHIPS FOR THE GOALS
0
Research Products
2
ZERO HUNGER
0
Research Products
This researcher does not have a Scopus ID.
This researcher does not have a WoS ID.
Scholarly Output
9
Articles
9
Views / Downloads
230/8
Supervised MSc Theses
0
Supervised PhD Theses
0
WoS Citation Count
387
Scopus Citation Count
454
WoS h-index
4
Scopus h-index
4
Patents
0
Projects
0
WoS Citations per Publication
43.00
Scopus Citations per Publication
50.44
Open Access Source
1
Supervised Theses
0
| Journal | Count |
|---|---|
| Environmental Technology | 2 |
| Energies | 1 |
| Environmental Engineering Science | 1 |
| Journal of Environmental Management | 1 |
| Process Biochemistry | 1 |
Current Page: 1 / 2
Scopus Quartile Distribution
Competency Cloud
9 results
Scholarly Output Search Results
Now showing 1 - 9 of 9
Article Citation - WoS: 98Citation - Scopus: 117Anaerobic Digestion of Dairy Manure With Enhanced Ammonia Removal(Academic Press Ltd- Elsevier Science Ltd, 2008) Uludag-Demirer, S.; Demirer, G. N.; Frear, C.; Chen, S.Poor ammonia-nitrogen removal in methanogenic anaerobic reactors digesting animal manure has been reported as an important disadvantage of anaerobic digestion (AD) in several studies. Development of anaerobic processes that are capable of producing reduced ammonia-nitrogen levels in their effluent is one of the areas where further research must be pursued if AD technology is to be made more effective and economically advantageous. One approach to removing ammonia from anaerobically digested effluents is the forced precipitation of magnesium ammonium phosphate hexahydrate (MgNH4PO4-6H(2)O), commonly called struvite. Struvite is a valuable plant nutrient source for nitrogen and phosphorus since it releases them slowly and has non-burning features because of its low solubility in water. This study investigated coupling AD and controlled struvite precipitation in the same reactor to minimize the nitrogen removal costs and possibly increase the performance of the AD by reducing the ammonia concentration which has an adverse effect oil anaerobic bacteria. The results indicated that Lip to 19% extra COD and almost 11% extra NH3 removals were achieved relative to a control by adding 1750 mg/L of MgCl2-6H(2)O to the anaerobic reactor. (C) 2007 Elsevier Ltd. All rights reserved.Article Citation - WoS: 18Citation - Scopus: 19A Study on Nutrient Removal From Municipal Wastewater by Struvite Formation Using Taguchi's Design of Experiments(Mary Ann Liebert, inc, 2008) Uludag-Demirer, SibelThe aim of this study is to investigate the removal of NH4+-N and PO43--P from the municipal wastewater by struvite (MgNH4PO4.6H(2)O) formation. The optimization of the NH4+-N and PO43--P removals is made by changing the total concentrations of struvite forming ions (Mg2+, NH4+, PO43-) and pH of the wastewater. The experimental design was made using Taguchi's L-9(3(4)) orthogonal array technique in the first stage of the study. The conditions yielding maximum removals of NH4+-N and PO43--P are found as molar concentration ratio of Mg:N:P of 2:2:2 and 3:3:2, respectively, using the signal-to-noise (S/N) ratio of experimental results. The removal of NH4+-N followed the stoichiometry of struvite formation, while PO43--P removal required the excess amount of Mg2+. The pH of wastewater in which the maximum NH4+-N and PO43--P removals are observed was 9.0. All of the factors tested influenced the removal of NH4+-N opposite to the removal Of PO43--P, in which the concentration of NH4+-N was found insignificant statistically. Therefore, the addition of NH4+ ion is eliminated and Taguchi's L-4(2(3)) orthogonal array was used in the second stage of experimental study. The molar concentration ratios of struvite forming ions (Mg:N:P) were found to be as 1:1:1 and 2:1:1 for maximum NH4+-N and PO43--P removals at the levels of 52.4 and 67.7%, respectively, at pH 9.0 using the S/N ratios of experimental results. The performance of proposed method in removing NH4+-N and PO43--P and foreseen problems related with effluent quality is discussed.Article Citation - WoS: 205Citation - Scopus: 231Ammonia Removal From Anaerobically Digested Dairy Manure by Struvite Precipitation(Elsevier Sci Ltd, 2005) Uludag-Demirer, S; Demirer, GN; Chen, SAmmonia is one of the most important contaminants impairing the quality of water resources. When this is considered along with the fact that the global demand for nitrogenous fertilizers is in constant rise, the need for recovery as well as removal of nitrogen is well justified. Crystallization of N and P in the form of struvite (MgNH4PO4 center dot 6H(2)O), which is a slow releasing and valuable fertilizer, is one possible technique for this purpose. This study investigated the removal of NR4+ through struvite precipitation from the effluents of one- (R1) and two-phase (R2) anaerobic reactors digesting dairy manure. To force the formation of struvite in the anaerobic reactor effluents, Ma(2+) ion was added by using both Mg(OH)(2) and MgCl2 center dot 6H(2)O. To prevent the effect of different total phosphorus (TP) concentration in the effluents of RI and R2, as well as to not limit the formation of struvite, an excess amount Of PO43- (0.14 M) was added in the form of NaHPO4. Different stoichiometric Mg2+:NH4+:PO43- ratios were tested to determine the required Mg2+ concentrations for maximum NH4+ removal by keeping NH4+:PO43- ratio constant for the effluents of reactors RI and R2. The results revealed that very high NH4+ removal efficiencies (above 95%) were possible by adding Mg 21 ions higher than 0.06 M concentration in the effluents from reactors RI and R2. It was also observed that the initial pH adjustment to 8.50 using NaOH did not result in any significant increase in the removal of NH4+ and the removal of NH4+ in the reactors treated with MgCl2 center dot 6H(2)O was higher than those treated with Mg(OH)(2) for the same Mg2+ concentration. (c) 2005 Published by Elsevier Ltd.Article Control of trichloroethylene emissions from sparging systems by horizontal bio- and chemo- barriers(2005) Tezel, U.; Demirer, G.N.; Uludag, Demirer S.The scope of this study was to develop a continuous system to clean-up a trichloroethylene (TCE) contaminated gas stream, where biotic and abiotic removal mechanisms are undertaken sequentially simulating the horizontal bio- and chemo-barriers proposed for the in-situ remediation of the contaminated sites. The bio- and chemo-barriers were simulated by using glass columns packed with granular anaerobic mixed culture and Fe(0) filings, respectively. The effect of gas residence time, which is adjusted by the gas flowrate, on the TCE removal efficiency of the reactor system was investigated. TCE removal efficiency of over 90% was achieved at gas residence times above 1hr. Furthermore, the effluent of reactor system contained only ethane and ethylene, which are non-toxic by-products of TCE reduction reactions, along with trace amounts of TCE.Article Citation - Scopus: 1Enhanced Nutrients Removal in Conventional Anaerobic Digestion Processes(2009) Othman, M.Z.; Uludag-Demirer, S.; Demirer, G.N.One of the main challenges for one phase anaerobic digestion processes is the high concentration of NH 4 + and PO 4 3- ions in the digested sludge supernatant. This project focuses on enhancing the removal of nutrients during the anaerobic digestion process through fixing both NH 4 + and PO 4 3- ions in the form of struvite (magnesium ammonium phosphate, MAP, MgNH 4PO 4.6H 2O) within the anaerobic sludge. Batch anaerobic digestion tests showed that Mg 2+ concentration in the range 279 - 812 mg/L had insignificant effect on CGP but incurred a slight increase in COD removal. The reactor that had soluble Mg 2+:NH 4 +:PO 4 3- at a molar ratio of 1.28:1:00:1:00 achieved the best performance enhancement of 8% increase in COD removal and 32% reduction in NH 4 + in the reactor supernatant. Overall, the results show that there is a potential to optimise conventional anaerobic digestion such that supernatant lean in P and N, and sludge rich in nutrients are obtained.Article Control of Trichloroethylene Emissions From Sparging Systems by Horizontal Bio- and Chemo-Barriers(Selper Ltd, Publications Div, 2005) Tezel, U; Demirer, GN; Uludag-Demirer, SThe scope of this study was to develop a continuous system to clean-up a trichloroethylene (TCE) contaminated gas stream, where biotic and abiotic removal mechanisms are undertaken sequentially simulating the horizontal bio- and chemo-barriers proposed for the in-situ remediation of the contaminated sites. The bio- and chemo-barriers were simulated by using glass columns packed with granular anaerobic mixed culture and Fe(0) filings, respectively. The effect of gas residence time, which is adjusted by the gas flowrate, on the TCE removal efficiency of the reactor system was investigated. TCE removal efficiency of over 90% was achieved at gas residence times above 1hr. Furthermore, the effluent of reactor system contained only ethane and ethylene, which are non-toxic by-products of TCE reduction reactions, along with trace amounts of TCE.Article Forecasting the Methane Yield of a Commercial-Scale Anaerobic Digestor Based on the Biomethane Potential of Feedstocks(Multidisciplinary Digital Publishing Institute (MDPI), 2025) Türker Bayrak, Ö.T.; Uludaǧ-Demirer, S.; Xu, M.; Liao, W.; Bayrak, Ozlem TurkerWith rising energy demand and the need for sustainable waste treatment, anaerobic digestion (AD) has emerged as a key technology for converting organic residues into renewable energy. However, predicting methane yield in full-scale facilities remains challenging due to the complexity of AD processes, the variability of feedstocks, and the impracticality of frequent biochemical methane potential (BMP) testing. In this study, we developed a simple, data-driven approach to forecast methane production in a commercial-scale digester co-digesting manure and food waste. The model employs weekly cumulative BMP of feedstock mixtures, calculated from literature values, as the explanatory variable. The model achieved an R2 of 0.70 and a forecast mean absolute percentage error (MAPE) of 7.4, indicating its potential for full-scale AD prediction. Importantly, the analysis revealed a long-run equilibrium between BMP and methane yield, with deviations corrected within roughly one month—closely matching the system’s hydraulic retention time. These findings demonstrate that literature-based BMP values can be used to reliably predict methane yield in operating AD systems, offering a low-cost and scalable tool to support decision-making in waste management and biogas plant operations. © 2025 by the authors.Article Citation - WoS: 66Citation - Scopus: 85Removal of Ammonium and Phosphate From the Supernatant of Anaerobically Digested Waste Activated Sludge by Chemical Precipitation(Elsevier Sci Ltd, 2009) Uludag-Demirer, Sibel; Othman, MaazuzaThe removal of ammonium (NH4+) and phosphate (PO43-) from supernatant of anaerobic digestion by magnesium ammonium phosphate (MAP) formation was Studied. To be able to find out the loss of NH4+ by its transformation to NH3, rates of NH4+ removal by aeration and by MAP formation combined with aeration were compared. NH4+ removal by aeration was found to be insignificant. The kinetics of MAP formation was fast. The removal rate of NH4+ and Mg2+ was the smallest and the largest, respectively based on rate constants calculated. The removal of NH4+ showed sensitivity to Mg2+ and PO43- concentrations and controlled the purity of MAP precipitate. The removal of PO43- was found to be Sensitive to mainly Mg2+ ion. These results also indicated that as the supernatant Solution became more saturated in terms of MAP forming ions, the effect of pH increase became insignificant in the removal of ions from the solution. (C) 2009 Elsevier Ltd. All rights reserved.Article Citation - Scopus: 1Identification of Eco-Efficiency Opportunities in a Small Enterprise Producing Vegetable Oil in Eskisehir, Turkey(Inderscience Publishers, 2007) Tepe, N.; Uludaǧ-Demirer, S.In this study, the current processes and technologies in a small enterprise, Demircanlar Oil Industry1 (Eskisehir, Turkey), were audited and improved from the eco-efficiency point of view. The eco-efficient management of the vegetable oil production processes has been performed on the units of physical processes, extraction and purification. The results obtained indicated that the loss in raw material can be reduced simply by increasing me height of the sieves used to separate foreign materials (leaves, sand, stones, etc.) from sunflower seeds. Results also indicated that production costs and negative environmental impacts can be decreased by minimising the loss of hexane during the extraction process, and the product quality can be improved and product loss can be prevented by adjusting the amounts of bleaching clay and TriSyl® in me bleaching process. Although the reduction in environmental impacts of the factory could not be valuated, the study showed that the factory can be managed more eco-efficiently without undergoing major process changes with an immediate benefit of approximately 12,000 USD. Copyright © 2007 Inderscience Enterprises Ltd.
