MYTH. – “Surface aeration has low efficiency compared to diffused aeration”
FACT: Diffused aeration tests well in clean water when the test tank is deep and diffuser density is high but in real conditions it is far less efficient. In activated sludge the clean water advantage is reduced to zero and even surpassed by aquaturbo® Model AER-AS Surface Aeration.
Membrane diffuser efficiency reduces over time due to a combination of factors: – loss of elastomeric properties; enlargement of membrane openings; biofouling and membrane rupture. aquaturbo® AER-AS efficiency remains constant for the entire life of the equipment.
When first installed the Alpha Factor for membrane diffusers is α0.5 – 0.6. This reduces to α0.2 – 0.3 as the diffuser degrades over time and when α(F) Alpha Fouling is taken into account.
When operating in domestic wastewater the Alpha Factor of aquaturbo® AER-AS remains constant for the entire life of the aerator at typically α0.95.
All things considered; the inflated efficiency claims of diffused aeration compared to surface aeration is a myth.