Abstract
The beverage industries release large amounts of wastewater containing organic and mineral pollutants (sodium). The conditions of biomass acclimation as well as the influence of environmental factors pertaining to the Sahelian context are not well documented in previous studies with regards to industrial wastewater treatment by membrane bioreactor (MBR). This work shows the biomass behavior during the acclimation period and the effluent treatment effectiveness. The experimental system consists of an association of anoxic and aerobic reactors with a ceramic ultrafiltration membrane followed by a nanofiltration unit as post-treatment for treated water reclamation. The hydraulic retention time ranged from 16 to 57 h and a solid retention time of 30 d was defined. The volume loads increased from 0.3 to 15.9 kg(COD) m(-3) d(-1). The results reveal the need for pH, temperature and feed flow control during start-up phase. COD removal rate up to 95% was reached at the end of the treatment step with a turbidity reduction of 92%. The nanofiltration allowed retention of more than 90% of the concentrations of principal ions contained in the treated wastewater with a COD and sodium concentration less than 175 and 186 mg/L, respectively.