Tracing Pollutants in Simultaneous Dephosphorization Failures of Biological and Chemical Phosphorus Removal at Wastewater Treatment Plants
WU Qinxiang
WANG Baichun
CAI Bohan
ZHANG Jintai
WEI Chuyun
ZHOU Ziqi
HUANG Zirui
ZHOU Aijiao
Abstract：The presence of specific pollutants in the water source of a wastewater treatment plant in Hubei Province has been linked to simultaneous failures in both biological and chemical phosphorus removal processes.This situation led to sludge bulking and violations of total phosphorus(TP)standards in the effluent.Identification of these pollutants and implementation of effective countermeasures are crucial to ensure the maintenance of water quality standards.Through the analysis of water quality data and experimental observations on the reactivity of potential pollutants(fluoride ions,sulfide ions,met-al complexing agents,organic acids)with polyferric chloride(PFC),tannic acid(TA)was identified as the critical agent.This compound exhibits both biological toxicity and strong complexation with PFC,significantly inhibiting the coagula-tion process.In scenarios with 80 mg/L of TA,TP removal efficiency was reduced to below 10％,necessitating a PFC dosage six times higher than normal to achieve standard TP removal efficiencies,mirroring the increased dosages re-quired during the phosphorus removal failures.To efficiently trace the pollutant sources,a rapid detection method was developed.This method enables quick analysis of the water quality in the inlet pipe network of the sewage treatment plant,screening for potential discharge points,thereby providing essential guidance for operational adjustments and ensur-ing compliance with environmental standards.
Keywords：dephosphorization failurespollutants tracingmetal complextannic acidpipe network investigation
Publication Date：2024-12-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：8( 115-122 )