A moving-boundary model of reactive settling in wastewater treatment. Part 2: Numerical scheme

by   Raimund Bürger, et al.

A numerical scheme is proposed for the simulation of reactive settling in sequencing batch reactors (SBRs) in wastewater treatment plants. Reactive settling is the process of sedimentation of flocculated particles (biomass; activated sludge) consisting of several material components that react with substrates dissolved in the fluid. An SBR is operated in cycles of consecutive fill, react, settle, draw and idle stages, which means that the volume in the tank varies and the surface moves with time. The process is modelled by a system of spatially one-dimensional, nonlinear, strongly degenerate parabolic convection-diffusion-reaction equations. This system is coupled via conditions of mass conservation to transport equations on a half line whose origin is located at a moving boundary and that models the effluent pipe. A finite-difference scheme is proved to satisfy an invariant-region property (in particular, it is positivity preserving) if executed in a simple splitting way. Simulations are presented with a modified variant of the established activated sludge model no. 1 (ASM1).



There are no comments yet.


page 19


A moving-boundary model of reactive settling in wastewater treatment

Reactive settling is the process of sedimentation of small solid particl...

A method-of-lines formulation for a model of reactive settling in tanks with varying cross-sectional area

Reactive settling denotes the process of sedimentation of small solid pa...

Numerical Simulation of Fecal Coliform Dynamics in Luruaco Lake, Colombia

The Luruaco Lake located in the Department of Atlántico, Colombia, is da...

Numerical solution of a two dimensional tumour growth model with moving boundary

We consider a biphasic continuum model for avascular tumour growth in tw...

A Structure-preserving, Operator Splitting Scheme for Reaction-Diffusion Equations Involving the Law of Mass Action

In this paper, we propose and analyze a positivity-preserving, energy st...

Addressing the issue of mass conservation error and the connected problem of Carbuncle formation

We study mass conservation errors (momentum density spike) and the relat...
This week in AI

Get the week's most popular data science and artificial intelligence research sent straight to your inbox every Saturday.