Process Optimization & Control
Anoxic-Zone Nitrate Monitoring at a Dalian WWTP
1 / 3Project Background
A 100,000 m³/d wastewater plant in Dalian operated by Beijing Capital treats predominantly industrial wastewater and must meet the strict Class 1A discharge standard.
Customer Challenge
Industrial-dominated influent swings wildly and carries high concentrations of pollutants and interfering ions. Manual lab data lagged hours behind the process, preventing timely carbon-dosing optimization and putting effluent compliance at risk.
The TENGINE Solution
TENGINE deployed TEM online COD and nitrogen analyzers with sampling pretreatment, sized for the plant's full range — the pretreatment stage shields the measurement from the complex industrial matrix.
Implementation
Analyzers with sampling pretreatment were installed at the anoxic-zone monitoring points, delivering stable readings despite the aggressive industrial water chemistry.
Project Results
Sampling pretreatment effectively resists industrial-water interference, keeping measurement stable. Online real-time data has replaced manual lab work, carbon dosing is optimized, and Class 1A effluent is secured.
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