High salinity wastewater treatment using yeast and bacterial membrane bioreactors.
Two laboratory-scale membrane bioreactor systems were investigated to treat high salinity wastewater containing high organic (5,000 mg/L COD) and salt content (32 g/L NaCl), namely: (1) the Yeast Membrane Bioreactor (YMBR) and; (2) Yeast pretreatment followed by Bacterial Membrane Bioreactor (BMBR). In the YMBR system, experimental runs were conducted with a mean biomass concentration of 12 g MLSS/L. Here the maximum COD removal rate of 0.93 g COD/g MLSS x day was obtained at F/M of 1.5 g COD/g MLSS.d. Whereas, the BMBR system was operated with a biomass concentration of up to 25 g MLSS/L, resulting in maximum COD removal rate of 0.32 kg COD/kg MLSS x day at F/M ratio of 0.4. In comparison to BMBR, YMBR could obtain higher COD removal rate at higher organic loading, indicating the potential of a yeast reactor system to treat high salinity wastewater containing high organic concentration. Transmembrane pressure in BMBR was progressively increased from 2 to 60 kPa after 12 d, 6 d and 2 d at a hydraulic retention time (HRT) of 14 h, 9 h and 4 h, with average biomass concentration of 6.1, 15 and 20 g MLSS/L, respectively. Whereas the transmembrane pressure in YMBR has increased from 2 to 60 kPa only after 76 days of operation, with an average biomass concentration of 12 MLSS/L and an operating HRT range of 5-32 h.
Dan
N P
NP
Urban Environmental Engineering and Management Program, School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani, Thailand.
Visvanathan
C
C
Polprasert
C
C
Ben Aim
R
R
D001419:Bacteria; D018533:Biomass; D019149:Bioreactors; D005374:Filtration; D008567:Membranes, Artificial; D010100:Oxygen; D011312:Pressure; D014865:Waste Disposal, Fluid / Q000379:methods*; D018508:Water Purification / Q000379:methods*; D015003:Yeasts
D008567:Membranes, Artificial; D010100:Oxygen