I. Observe Aeration Performance
1. Check aeration uniformity
Observe the surface of the aerobic tank. Under normal operation, air bubbles emerge evenly across the entire water surface. For rectangular aerobic tanks, inspect along the tank edges. If bubbles are sparse or absent in certain zones, this may indicate defective aeration heads or unreasonable layout. When comparing zones served by different branch pipelines, weak aeration in one branch area usually results from damaged, clogged or leaky vortex aerators, leading to uneven aeration.
2. Check bubble shape and size
A properly functioning vortex aerator generates uniformly sized medium bubbles. Excessively large bubbles point to faulty aeration heads or abnormal orifice sizes, which reduce oxygen mass transfer efficiency. Monitor bubble continuity; intermittent bubbling suggests unstable air supply caused by blower malfunctions or blocked pipelines that hinder gas delivery.
II. Test Dissolved Oxygen (DO) Level
1. Measure with a dissolved oxygen meter
Place the DO probe at multiple sampling points in the aerobic tank. The standard target DO concentration ranges from 2 to 4 mg/L. If readings are consistently below this range and fail to rise, the aeration equipment is likely faulty. Extremely low DO at isolated points with normal readings elsewhere indicates uneven aeration, requiring inspection of aerators in the corresponding zones.
2. Compare with historical data
Record DO values of the aerobic tank regularly. Evaluate the aerator condition by matching current readings against data logged during stable normal operation. If DO drops significantly while external conditions such as influent water quality and water temperature remain unchanged, insufficient oxygen supply caused by vortex aerator failure is the primary cause, which impairs microbial metabolism and wastewater treatment efficiency.
III. Inspect Aeration Equipment Appearance and Operating Parameters
1. Inspect aerator heads
Drain the aerobic tank if feasible, then conduct manual underwater inspection to check aerator heads for clogging and breakage — both issues lead to uneven aeration and abnormal bubble patterns.
2. Check blower operating parameters
Read real-time data via control panels or monitoring software. All readings should stay within rated ranges. Low air volume and air pressure often stem from impeller wear that limits air supply. Erratic fluctuations of electric current and rotational speed signal mechanical defects or electrical control faults disrupting air delivery.
3. Inspect aeration pipelines
Walk the full length of pipelines for inspection. Listen for abnormal air leakage noise or apply soapy water to pipeline surfaces — bubbles forming on the surface confirm leaks that weaken aeration. Tap pipelines lightly to preliminarily judge internal blockages; an endoscope can be used for further internal inspection. Blockages restrict gas flow and create uneven aeration.
IV. Monitor Wastewater Treatment Effect
1. Observe organic matter removal efficiency
With adequate aeration, COD and BOD concentrations of wastewater decrease with hydraulic retention time. If effluent pollutant levels show no improvement and influent quality is stable, insufficient DO from aerator failure is the main factor undermining treatment performance.
2. Check activated sludge characteristics
Healthy sludge in aerobic tanks presents a yellowish-brown color, well-formed flocs and good settleability. Faulty aeration turns sludge black with loose flocs and poor settling performance, serving as an indirect indicator of abnormal vortex aerator operation.
Comprehensive evaluation based on the above four aspects enables accurate judgment of whether vortex aerators work normally, facilitating timely fault detection and corresponding troubleshooting.