Environmental Engineering Reference
In-Depth Information
Condition:
Waste rate is too low.
result:
•
Increased
MLSS
•
Increased sludge density
•
Decreased
SVI
•
Increased
MCRT
•
Decreased F/
M ratio
8.13.7.3 Process Control: Aeration Rate
Condition:
Aeration rate is too high.
result:
•
Wasted energy
•
Increased operating cost
•
Rising solids
•
Breakup of activated sludge
Condition:
Aeration rate is too low.
result:
•
Septic
aeration tank
•
Poor performance
•
Loss of
nitrification
8.13.8 Troubleshooting operational Problems
Without a doubt, the most important dual function performed by
the wastewater operator is the identification of process control prob-
lems and implementing the appropriate actions to correct the problems.
This section lists typical aeration system operational problems with
their symptoms, causes, and appropriate corrective actions to restore
the unit process to a normal or optimal performance level.
•
symptom 1.
The solids blanket is flowing over the effluent weir
(classic bulking). Settleability test shows no settling.
Cause:
Organic overloading
Corrective action:
Reduce organic loading.
Cause:
Low pH
Corrective action:
Add alkalinity.
Cause:
Filamentous growth
Corrective action:
Add nutrients; add chlorine or peroxide to
return.
