UNCOVERING THE POTENTIAL IMPACT OF SIMULTANEOUS CHEMICAL PHOSPHORUS REMOVAL ON AN INVERTED AAO SYSTEM BY WHOLE PROCESS DIAGNOSIS METHOD
In order to respond to the Implementation Opinions on Promoting Synergy and Efficiency Enhancement of Wastewater Treatment for Pollution and Carbon Reduction,and comprehensively promote the reduction of pollution and carbon emissions in the urban wastewater treatment industry,a whole process analysis was conducted on a simultaneous chemical phosphorus removal WWTP in Wuxi,to diagnose the impact of phosphorus removal agent dosage on process stability,and explore the agent-saving method of the inverted AAO process.This WWTP adopts an Anoxic/Anaerobic/Aerobic(inverted AAO)process,with a treatment capacity of 150000 m3/d.The stable effluent quality is ensured through the long-term addition of PAFC.Through the whole process analysis,it was found that the PAFC consumption in the phase Ⅰ project of the WWTP has been increasing year by year.Although the efficient removal of TP(98%)has been achieved,a large amount of residual PAFC flows back to the anaerobic section,leading to early removal of phosphorus and deterioration of the phosphorus absorption capacity of activated sludge(AS).The phosphorus absorption rate was only 0.44 mg P/(g SS·h).Therefore,this study further conducted the PAFC dosage regulation experiment in the Phase Ⅰ project to gradually restore the phosphorus absorption capacity of AS.The results showed that a controlled PAFC dosage at 0.027 kg/m3 to 0.053 kg/m3 can help achieve stable removal of phosphorus while ensuring sludge settling performance.However,PAFC with a higher dosage(0.077 kg/m3 above)will quickly remove phosphorus and significantly inhibit the aerobic phosphorus absorption process.
inverted AAO systemsimultaneous chemical phosphorus removalwhole process diagnosissedimentation performancePAFC