Date of Award
Master of Science
Civil, Construction, and Environmental Engineering
Civil Engineering (Environmental Engineering)
Membrane biological reactors (MBR) are seen as the next generation of wastewater treatment plants. The objectives of this study were to investigate the physical operating characteristics of a tubular ceramic membrane and to assess its performance for synthetic wastewater and phenol treatment under low hydraulic retention time (HRT) and high solids residence time (SRT). Laboratory studies were conducted using a tubular ceramic membrane biological reactor under varying mixed liquor suspended solid (MLSS) concentrations, membrane feed rates (MFR), and permeate flux (PF) rates to characterize and evaluate the MBR performance and operating conditions. An operating schedule of 15 minutes of operation with 15 seconds of backwashing at 250 L/m2/hr along with an extended backwashing of 30 seconds every 3 hours of operation was sufficient to maintain the transmembrane pressure (TMP) at less than 140 kPa. Using a synthetic wastewater, the chemical oxygen demand and suspended solids removals were greater than 88% and 99.99%, respectively, even for HRT as low as 2 hours and SRT of 20 days. The TMP was correlated with several operating parameters as well as the time of operation using stepwise regression analysis. PF and MLSS were found to impact the TMP more than MFR. For the treatment of phenolic wastewater, the membrane was operated with a mode of 15 minutes of filtration followed by 15 seconds of permeate backwashing at 250 L/m2/hr along with an extended backwashing of 30 seconds every 3 hours of operation, which maintained the TMP below 100 kPa. When the TMP reached 100 kPa, an extended backwashing of 2 minutes at 250 L/m2/hr was conducted. The chemical oxygen demand and phenol removals were found to be greater than 88% with excellent suspended solids removal of 99.99% at an influent phenol concentration of 100 mg/L for 4 hours HRT and 30 days SRT. Inhibition of phenol removal was found between 600 and 800 mg/L of phenol with decreased sludge production and increased sludge volume index. Experimental runs using wastewater containing phenol indicated that the MBR can be operated safely at 600 mg/L phenol concentration at 4 hours HRT and 30 days SRT without upsets.
Cagatayhan Bekir Ersu
Ersu, Cagatayhan Bekir, "Tubular ceramic membrane bioreactor: operating characteristics and treatment performance" (2003). Retrospective Theses and Dissertations. 19959.