Process Optimization & Control
Intelligent Carbon-Source Dosing Control at a Qingdao WWTP
1 / 4Project Background
A municipal wastewater plant in Qingdao set out to replace experience-based carbon dosing with closed-loop control in its bioreactors — one of the most direct levers a plant has over both effluent total nitrogen and reagent cost.
Customer Challenge
Biological denitrification needs precise nitrate readings to dose carbon source intelligently. Manual dosing is inaccurate — wasting reagent or risking total-nitrogen exceedance. Bioreactor samples also carry heavy impurities that foul instruments and demand frequent cleaning.
The TENGINE Solution
A UVN nitrate nitrogen analyzer with built-in wiper self-cleaning was installed in the bioreactor, providing the stable, accurate long-term nitrate signal that automatic dosing control requires.
Implementation
The UVN analyzer was deployed directly in the bioreactor with wiper self-cleaning, feeding continuous nitrate data to the dosing control loop.
Project Results
Intelligent automatic carbon dosing is now reality: reagent consumption is down, maintenance is reduced by self-cleaning, and reliable data keeps nitrification/denitrification stable with effluent total nitrogen compliant.
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