Flux Behavior and Quality of Effluent from a Poultry Processing Plant Treated by Membrane Bioreactor

Abstract

Abstract Membrane bioreactor (MBR) provided with spiral wound modules of polyacrylonitrile ultrafiltration membranes was used to treat the wastewater obtained from primary and secondary processing operations of a poultry plant. The membrane bioreactor consisted of 3 tanks; an aerobic bioreactor, anoxic settling tank, and a third tank from which a permeate was drawn across ultrafiltration membranes for final discharge to a municipal sewer or for reuse in the processing of raw product. The Cleaning and backflush schedules were conducted to determine the best regimen for maximum permeate flux and for their effect on retention times in each of the biological treatment tanks. Continuous operation of MBR for 24 h period with no backflushing resulted in flux decay that led to a substantial change in retention times. The best operating cycle was found to be 1 h filtration followed by 120 s backflush or 20 min filtration followed by 20 s backflush. Significant reduction in particle size, COD and BOD (>90%) and reduction of microbial load by 4 – log levels in MBR effluent made it fit for reuse.