why a suspended growth anaerobic reactor gives very poor COD removal when used for treatment of domestic wastewater

Question

anonymous · Answer

Anaerobic must be maintained at very low specific  growth rates for obtaining low effluent COD values. This means that very high biomass concentration must be maintain in the reactor to achieve reasonable rates of substrate utilization.
In suspended growth system maintenance of high biomass concentration is  only possible if the biomass escaping from the reactor is settled and recycled back efficiently. However this is difficult  in anaerobic reactors because anaerobic sludge has poor settling characteristics. Wily consider this idea.

anonymous · Answer

listen to the man, he has got a point.