Enhanced Treatment Strategies on Refractory Organics of An Urban Wastewater Treatment Plant

Abstract

A 15×10⁴ m³/d scale urban wastewater treatment plant used the process of hydrolysis acidification+conventional treatment+advanced treatment. Take it as an example, enhanced treatment on refractory organics were introduced and analyzed. Almost 50% influent wastewater come from industry drainage (papermaking, pharmacy ), which contained a lot of refractory organics, and its quality fluctuated seriously. During the early operation period, the average influent and effluent COD were around 310 mg/L and 100 mg/L, respectively. Through increasing the MLSS of hydrolysis acidification pool, altering the sludge external reflow to system entire reflow, decreasing the air blower supply quantity, extending anaerobic pool hydraulic retention time, and so on, the refractory organics removal was enhanced effectively without any reagents addition. Its design and operation experiences provide technical reference for similar urban wastewater treatment plant.