Dynamic modelling of solids in a full-scale activated sludge plant preceded by CEPT as a preliminary step for micropollutant removal modelling

Abstract

The presence of micropollutants in the environment has triggered research on quantifying and predicting their fate in wastewater treatment plants (WWTPs). Since the removal of micropollutants is highly related to conventional pollutant removal and affected by hydraulics, aeration, biomass composition and solids concentration, the fate of these conventional pollutants and characteristics must be well predicted before tackling models to predict the fate of micropollutants. In light of this, the current paper presents the dynamic modelling of conventional pollutants undergoing activated sludge treatment using a limited set of additional daily composite data besides the routine data collected at a WWTP over one year. Results showed that as a basis for modelling, the removal of micropollutants, the Bürger–Diehl settler model was found to capture the actual effluent total suspended solids (TSS) concentrations more efficiently than the Takács model by explicitly modelling the overflow boundary. Results also demonstrated that particular attention must be given to characterizing incoming TSS to obtain a representative solids balance in the presence of a chemically enhanced primary treatment, which is key to predict the fate of micropollutants

Revisiting Chemically Enhanced Primary Treatment of Wastewater: A Review

“…In CEPT, due to the coagulation and flocculation process, the colloidal fraction is significantly removed, resulting in very low to no colloidal COD in the effluent. It should be noted that a well-operated CEPT is capable of almost completely removing colloidal matter [81]. Therefore, Colloidal COD for conventional primary effluent wastewaters ranges from 29 to 36% of the total COD [80].…”

“…In CEPT, due to the coagulation and flocculation process, the colloidal fraction is significantly removed, resulting in very low to no colloidal COD in the effluent. It should be noted that a well-operated CEPT is capable of almost completely removing colloidal matter [81]. Therefore, assuming a typical total COD concentration of conventional primary effluent (290 mg/L) and considering only the colloidal COD removal that can be achieved by CEPT, the total COD concentration in the CEPT effluent could range from 186 to 206 mg/L.…”

Fault Detection in the Activated Sludge Process using the Kohonen Self-Organising Map

“…Moreover, most of these models have been proposed to estimate the dynamic behaviour of both the biological reactor and the secondary settler, whereas very few models incorporate the interconnection between both of these units [1]. In addition, these models were developed using data obtained under controlled laboratory conditions and are therefore, more suitable for the design of treatment plants rather than operational control, with very few of the models validated with real field data [6]. In recent years, numerous researchers have undertaken fault detection studies in wastewater treatment [7][8].…”