Comparison between a Moving Bed Membrane Bioreactor and a Conventional Moving Bed Biofilm Reactor (MBBR)

The combination of moving bed biofilm reactors and membrane bioreactors can compensate for the drawbacks of both of these systems and further increase their acceptance and application in wastewater treatment industries. The objective of this study is comparison between a moving bed membrane bioreactor and a conventional Moving Bed Biofilm Reactor (MBBR).The study was carried out using a hollow fiber microfiltration membrane. The pilot plant consisted of two separated 30 liters reactors with KMT carriers, one with membrane and one without it. The carrier filling fraction was 40%. The synthetic wastewater contained molasses and other salts as nutrient source. The COD of the feed was in three various concent ratios (500-1000-2000 mg/L) with different hydraulic retention times (10-15-20 hr) which responds to organic loading rates between 0.6-4.8 (kgCOD / m3d). The removal efficiency of COD for permeate was 92-98%, for biological treatment in the reactor was 89-96% and for conventional MBBR was 87-96%. The MLSS content increased from 4000 to 9230 in the reactor with membrane and decreased from 4000 to 2450 in the conventional MBBR.