Question

Explain the consequences if the oxygen availability to activated sludge flocs is reduced to

Answer 1

The oxygen is consumed by the microorganisms while consumption or digestion of organic matter in the reactor. The rate at which oxygen is consumed is called Oxygen utilization rate. Since oxygen is being consumed, the oxygen will getting depleted from the reactor.

In activated sludge, there is a high concentration of microorganisms, the oxygen utilization rate is higher than rate of natural replenishment. Thus if oxygen availability to activated sludge flocs reduced, the microorganisms can't survive longer and concentration of biomass will reduce and sludge will no more activated sludge and digestion (food utilization) will stop.