# COMPUTER SIMULATION OF BIOLOGICAL WASTEWATER TREATMENT PROCESSES IN AEROTANKS WITH PLATES

## Authors

• M. M. Biliaiev Dnipro National University of Railway Transport named after Academician V. Lazaryan, Ukraine
• M. V. Lemesh Dnipro National University of Railway Transport named after Academician V. Lazaryan, Ukraine
• V. V. Biliaeva Oles Honchar Dnipro National University, Ukraine
• P. B. Mashykhina Dnipro National University of Railway Transport named after Academician V. Lazaryan, Ukraine
• Z. M. Yakubovska Ukrainian State University of Chemical Technology, Ukraine

## Keywords:

water purification, numerical modeling, aerotank, model Mono, CFD models, biological cleaning, wastewater, ac-tivated sludge, concentration of pollutants

## Abstract

Purpose. Efficiency determination of the aeration tank at the stage of design or reconstruction of bioreactors in which biological wastewater treatment is carried out requires the use of special mathematical models and calculation methods. The main purpose of the article is to develop CFD models for evaluating the operation efficiency of aeration tanks. Methodology. A numerical model has been developed for the computer calculation of the biological wastewater treatment process in aerotanks, taking into account hydrodynamics. The model is based on two-level mass conservation equations for the substrate and activated sludge and the velocity potential equation. The process of biological transformation of the substrate is calculated based on the Monod model. For the numerical integration of the mass transfer equations of activated sludge and substrate, the alternating-triangular difference splitting scheme is used. In this case, the basic equations are divided into two equations of a more simplified form. For the numerical integration of the equations for the velocity potential, it is split into two one-dimensional equations. Further, each equation is solved according to explicit scheme. For the numerical integration of equations that describe the process of substrate transformation based on the Monod model, the Euler method is used. Findings. The software implementation of the constructed numerical model has been carried out. The results of a computational experiment on the study of the wastewater treatment process in an aeration tank with plates are presented. This leads to the conclusion that the quality control of wastewater treatment in aeration tanks is possible with the help of plates. Originality. A multivariate CFD model has been developed, which makes it possible to quickly assess the efficiency of the aeration tank. A feature of the model is the ability to evaluate the operation of the aeration tank, taking into account its geometric shape and location of additional plates in the construction. Practical value. The constructed numerical model can be used during calculations in the case of designing aeration tanks, or in determining the efficiency of wastewater treatment under new operating conditions.

## Author Biographies

### M. M. Biliaiev, Dnipro National University of Railway Transport named after Academician V. Lazaryan

Dep. «Hydraulics and Water Supply», Dnipro National University of Railway Transport named after Academician V. Lazaryan, Lazaryana St., 2, Dnipro, Ukraine, 49010, tel. +38 (056) 273 15 09, e-mail water.supply.treatment@gmail.com

### M. V. Lemesh, Dnipro National University of Railway Transport named after Academician V. Lazaryan

Dep. «Hydraulics and Water Supply», Dnipro National University of Railway Transport named after Academician V. Lazaryan, Lazaryana St., 2, Dnipro, Ukraine, 49010, tel. +38 (056) 273 15 09, e-mail water.supply.treatment@gmail.com

### V. V. Biliaeva, Oles Honchar Dnipro National University

Dep. «Fluid Dynamics, Energy and Mass Transfer», Oles Honchar Dnipro National University, Haharina Av., 72, Dnipro, Ukraine, 49000, tel. +38 (056) 374 98 22, e-mail water.supply.treatment@gmail.com

### P. B. Mashykhina, Dnipro National University of Railway Transport named after Academician V. Lazaryan

«Hydraulics and Water Supply», Dnipro National University of Railway Transport named after Academician V. Lazaryan, Lazaryana St., 2, Dnipro, Ukraine, 49010, tel. +38 (056) 273 15 09, e-mail gidro_eko@ukr.net

### Z. M. Yakubovska, Ukrainian State University of Chemical Technology

Dep. «Physics», Ukrainian State University of Chemical Technology, Haharina Av., 8, Dnipro, Ukraine, 49005, tel. +38 (056) 753 56 38, e-mail physics@udhtu.edu.ua

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2021-07-07

## How to Cite

Biliaiev, M. M., Lemesh, M. V., Biliaeva, V. V., Mashykhina, P. B., & Yakubovska, Z. M. (2021). COMPUTER SIMULATION OF BIOLOGICAL WASTEWATER TREATMENT PROCESSES IN AEROTANKS WITH PLATES. Science and Transport Progress. Bulletin of Dnipropetrovsk National University of Railway Transport, (5(89), 5–14. https://doi.org/10.15802/stp2020/218302

## Section

ECOLOGY AND INDUSTRIAL SAFETY