6th MEMTEK International Symposium on Membrane Technologies and Applications, İstanbul, Türkiye, 18 - 20 Kasım 2019
The study explored the potential of operating an up-flow sulfate reducing fluidized bed membrane bioreactor (SR-FMBR) at room temperature for biogenic sulfide generation and neutralizetion together with evaluation of filtration and fouling characteristics developed under various operational conditions. The feed sulfate concentrations were kept at 2,003±68 mg/L, whereas feed organic matter (ethanol) concentrations tested were 1,500 (1,484±35) mgCOD/L and 2,000 (2,001±96) mgCOD/L to attain COD/SO4 (mg/mg) ratios between 0.75 to 1. The system was tested for a total of 140 days. After initial 67 days of operation at 35 0C, temperature was controlled at room temperature (23 0C±0.65) during the remaining 73 days. SR-FMBR was able to achieve COD oxidation efficiencies up to 98 %, and SO4 reduction efficiencies up to 95 % and allow for biogenic sulfide generation up to an average of 604±28 mg/L (96 % of theoretical value) at room temperature. The alkalinity generation averaged 1,835±169 mg/L CaCO3. The system proved notable filtration performance while maintaining filtration flux values up to 9.25 L/(m2.h) (LMH) at employed hydraulic retention times between 24 h and 6 h. Chemical cleaning was only applied during the start-up phase together with frequent physical cleanings after which transmembrane pressure (TMP) profile remained below 220 mbar during the entire operation period.
Key Words: Sulfate reducing process, biogenic sulfide generation; anaerobic fluidized bed membrane bioreactor; low temperature; filtration characteristics