Stability and control of a partial nitritation reactor with biomass retention

TitleStability and control of a partial nitritation reactor with biomass retention
Publication TypeJournal Article
Year of Publication2019
AuthorsJamilis M, Garelli F, De Battista H, Volcke EIP
JournalChemical Engineering Research and Design
Volume144
Pagination318-333
Date Published04/2019
ISSN0263-8762
KeywordsAnammox, Bacteria Competition, Control, Equilibrium Points, Partial nitritation
Abstract

Partial nitritation-anammox process is an interesting process option for biological nitrogen removal from wastewater. Partial nitritation needs to provide about equimolar ammonium and nitrite concentrations as required for the Anammox conversion. This study analyzes the equilibrium points of a stand-alone partial nitritation process as part of a two-reactor partial nitritation-anammox configuration. Conditions for the feasibility and stability of the equilibrium points are obtained in the general case of a reactor with biomass retention and controlled oxygen concentration. This knowledge is subsequently applied to achieve the desired reactor behavior, namely suppressing nitrite oxidizing bacteria (NOB) and obtaining the desired effluent nitrite:ammonium ratio. The optimal oxygen concentration to achieve these two objectives is determined. Moreover, a control algorithm is proposed to drive the process to the desired operating point. Its steady state behavior is assessed for changing influent ammonium concentrations and biomass retention times. The dynamic performance of the controller is tested through simulation as well, prioritizing NOB suppression in case the two objectives are not compatible.

URLhttp://www.sciencedirect.com/science/article/pii/S0263876219300644
DOI10.1016/j.cherd.2019.02.017
Research Line: 
Control de sistemas y procesos biológicos
Control of biological processes and systems
Control and monitoring of bioprocesses
Control y monitoreo de bioprocesos