The Effects of seed sludge type and anoxic / aerobic period sequence on aerobic granulation and KOD, N treatment performance

Erşan, Yusuf Çağatay
The aim of this master thesis study was improvement of the required operational conditions for aerobic granulation in sequencing batch reactors (SBRs). In the first part of the study, membrane bioreactor sludge (MBS) and conventional activated sludge (CAS), were used to investigate the effect of suspended seed sludge type on granulation in SBRs. The MBS granules were found to be advantageous in terms of size, resistance to toxic effects, stability and recovery compared to CAS granules. During non-inhibitory conditions, sCOD removal efficiencies were 70±13% and 67±11% for MBS and CAS, and total nitrogen (TN) removal efficiencies were 38±8% and 26±8%, respectively. In the second part of the study, the effects of period sequence (anoxic-aerobic and aerobic-anoxic) on aerobic granulation from MBS, and sCOD, N removal efficiencies were investigated. Granules developed in anoxic-aerobic period sequence were more stable and larger (1.8-3.5 mm) than granules developed in aerobic-anoxic sequence. Under steady conditions, almost 95% sCOD, 90% Total Ammonia Nitrogen (TAN) and around 39-47 % of TN removal was achieved. Almost 100% denitrification in anoxic period was achieved in anoxic-aerobic period sequence and it was observed around 40% in aerobic-anoxic period sequence. The effects of influent sulfate (from 35.1 mg/L to 70.2 mg/L) on treatment efficiencies of aerobic granules were also investigated. The influent SO42- concentrations of 52.6 mg/L to 70.2 mg/L promoted sulfate reduction. The produced sulfide (0.24 mg/L to 0.62 mg/L) inhibited the ammonia-oxidizing bacteria (AOB) performance by 10 to 50%.


The effects of alkali promoters on the dynamics of hydrogen chemisorption and syngas reaction kinetics on Ru/SiO2 surfaces
Üner, Deniz; Pruski, M; King, TS (1997-01-01)
The dynamics of chemisorbed hydrogen on unpromoted and promoted Ru/SiO2 catalysts was studied by means of single pulse and selective excitation H-1 NMR spectroscopy. Dynamic NMR studies indicated a reduced mobility of hydrogen in the presence of alkali promoters (Na and K) at high loadings (65 atomic %). On unpromoted Ru/SiO2 catalysts, the line due to hydrogen-on-metal was homogeneously broadened at pressures above 0.5 Torr H-2. Similar behavior was observed on promoted Ru/SiO2 catalyst with 66 atomic % K....
Investigation of influent COD/TAN ratio and loading rate effects on carbon and nitrogen removal via aerobic granules
Kocatürk, İrem; Bayramoğlu, Tuba Hande; Department of Environmental Engineering (2014)
Aerobic granulation serves as a promising treatment technology over the conventional systems due to its advantages such as high biomass retention capacity, high settleability, ease of separation from the effluent, toxicity resistance, capacity to handle high organic loading rates and suitability for high chemical oxygen demand (COD) wastewaters. The scope of the thesis is to investigate the influent COD/total ammonifiable nitrogen (TAN = NH4-N + NH3-N) ratio and loading rate effects for the removal of carbo...
The effect of soluble boron on the burnup at different enrichments and assemblies
Gündüz, Güngör; Ajwah, Yousef (Elsevier BV, 1989-5)
The effect of boron on the optimum burnup was investigated at different assemblies for enriched fuels. As the enrichment increases, an alteration in the assembly type is needed for the optimum specific power. This alteration can be made at lower enrichments due to the presence of boron. The optimum specific power is shifted toward the high enrichment fuels when the assembly number is increased. If a fuel of high enrichment is first burnt in a highly hardened neutron spectrum and later in a softer spectrum t...
Integrated carbon dioxide mitigation and nutrient removal from municipal and industrial wastewater using microalgal systems
Kılıç, Gece Cansu; Bayramoğlu, Tuba Hande; Uludağ Demirer, Sibel; Department of Environmental Engineering (2017)
The aim of this master thesis study is to investigate the nutrient removal efficiency from different kinds of wastewaters and the carbon dioxide mitigation in photobioreactors with unialgal culture, Chlorella vulgaris. In the first part of the study, Chlorella vulgaris culture was cultivated in the Bold’s basal medium in batch reactors to increase the biomass content and to observe the growth phases of alga. Then, two parallel photobioreactors (PBRs) were run to cultivate Chlorella vulgaris culture semi-con...
The effects of aerobic/anoxic period sequence on aerobic granulation and COD/N treatment efficiency
Erşan, Yusuf Çağatay; Bayramoğlu, Tuba Hande (Elsevier BV, 2013-11)
The effects of period sequence (anoxic-aerobic and aerobic-anoxic) on aerobic granulation from suspended seed sludge, and COD, N removal efficiencies were investigated in two sequencing batch reactors. More stable granules with greater sizes (1.8-3.5 mm) were developed in R1 (anoxic-aerobic sequence). Yet, no significant difference was observed between the reactors in terms of removal efficiencies. Under optimum operational conditions, 92-95% COD, 89-90% TAN and 38-46% total nitrogen removal efficiencies we...
Citation Formats
Y. Ç. Erşan, “The Effects of seed sludge type and anoxic / aerobic period sequence on aerobic granulation and KOD, N treatment performance,” M.S. - Master of Science, Middle East Technical University, 2013.