Parametric optimization of domestic wastewater treatment in an activated sludge sequencing batch reactor using response surface methodology

Abstract

In this work, the parametric optimization of real domestic wastewater treated in an activated sludge sequencing batch reactor (SBR) was performed by means of the response surface methodology (RSM). The influences of influent organic matter concentration as chemical oxygen demand (COD_inf), biomass concentration (X_s) and aeration time (t) on the COD, organic matter removal efficiency as COD (η) and sludge volume index (SVI) were determined to evaluate the performance of activated sludge SBR. The results showed that organic matter efficiency and maximum SVI were obtained at a t of 12 h, 300 mg L⁻¹ of COD_inf and 2000 mg L⁻¹ of X_s. The SBR-activated sludge exhibited a η of 73% and an SVI of 119 mL g⁻¹. Both values indicated a very good performance. Furthermore, the COD of the effluent under these conditions complied with Mexican regulations for wastewater discharged into water bodies.

Keywords:

• Activated sludge
• chemical oxygen demand (COD)
• parametric optimization
• sequencing batch reactor (SBR)
• response surface methodology (RSM)

Additional information

Funding

The authors are grateful to PRODEP for providing financial support to carry out the project DSA/103.5/16/10242 with CUP: 2II1605 (entitled Simulation and Control of Degradation of Pollutants at Filter-Press-Type Electrochemical Reactor, for the use of Design Expert^® V.10 Software) and to Mexican Council of Science and Technology (CONACyT) for providing financial support through scholarship No. 791490 granted to one of the authors (A.N.S.P.).