Model identification, calibration and validation of the aerobic stage in water remediation of a paper mill effluent Chapter uri icon

abstract

  • The activated sludge process is the most common treatment for pulp and paper mill effluents. Process modelling is a powerful tool to increase the knowledge of wastewater treatment plants, with the benefits, for instance, of reducing costs and time for making decisions on process improvement. Frequently, ASM models are used to describe the pulp and paper mill effluents treatment. These types of effluents usually have low nutrients contents, which affect the biomass growth and in consequence, the process efficiency. In this work, a mathematical model which includes the dynamic influence of adding nutrients to the aerobic stage of a paper mill industry is retrieved, identified, calibrated and validated, in order to gain knowledge on the process for efficiency, in which the nutrients (ammonium phosphate) are added by an auxiliary inflow. Due to practical purposes, the developed model considers only seven out of nineteen biological processes in the ASM2. To get a reliable mathematical model for the process, we followed a five-step methodology that includes: (a) problem definition, (b) experimental data obtainment, (c) model construction (d) model calibration and (d) linear error propagation for uncertainty analysis. The reduced ASM2 contains 31 parameters that were calibrated by a non-linear regression with real data plant. This step was applied to four operational scenarios, with and without variation of the KLa parameter, as well as with and without effluent recirculation of the clarifier. The results show that the reduced ASM2, developed here, shows good responses that can be identified to the real process. Therefore, it can be used confidently for operational decisions for improvement of the process. © 2017 Elsevier B.V.

publication date

  • 2017-01-01