Over-Aeration / Excess DO
DO consistently runs well above setpoint, wasting energy and potentially harming floc structure.
Symptoms: DO consistently 4+ mg/L when target is 1.5–2.5 mg/L, high blower energy costs, possible pin floc from excess shear.
Probable Causes: blower control not tuned to actual demand, manual gate/valve settings left too high after a past high-load event, or a DO probe reading falsely low, causing the control system to overcompensate.
Troubleshooting Steps: 1) Verify DO probe accuracy against a portable calibrated meter. 2) Review blower control setpoints and automation logic — enable DO-based automatic control if currently running on manual/fixed output. 3) Reduce output incrementally and monitor for 24–48 hours to confirm process stability before settling on a new setpoint.
The industry's most useful newsletter, straight from the plant floor.
One email. No fluff. New lessons, equipment breakdowns, and process control notes, delivered when there's something worth reading.