Dissolved oxygen control for activated sludge processes

Controllers for dissolved oxygen reference trajectory tracking for activated sludge processes are proposed and investigated. A nonlinear model predictive controller and a direct reference adaptive controller are investigated. Both the nutrient and the phosphorous removal from a wastewater by its biological treatment using an activated sludge technology are considered. An approach to the controller design utilises a structure of the dissolved oxygen dynamics and its two time scales: fast and slow. The predictive controllers offer good tracking performance and robustness. The direct model reference adaptive controller is much simpler to implement. However, it is more difficult to compromise between tracking accuracy and rate of change and magnitudes of the control actions. The controllers are validated by simulation using real data sets and an ASM2d model of the biological reactor.

[1]  Jean-Luc Gouzé,et al.  Estimation of uncertain models of activated sludge processes with interval observers , 2001 .

[2]  L.J.S. Lukasse,et al.  Optimal control of N-removal in ASPs , 1998 .

[3]  Mietek A. Brdys,et al.  APPLICATION OF FUZZY MODEL PREDICTIVE CONTROL TO THE DISSOLVED OXYGEN CONCENTRATION TRACKING IN AN ACTIVATED SLUDGE PROCESS , 2002 .

[4]  Jan M. Maciejowski,et al.  Predictive control : with constraints , 2002 .

[5]  Hyunook Kim,et al.  SBR System for Phosphorus Removal: Linear Model Based Optimization , 2001 .

[6]  M. R. Katebi,et al.  The generic control structure of wastewater treatment systems , 2002 .

[7]  Mogens Henze,et al.  Activated sludge models ASM1, ASM2, ASM2d and ASM3 , 2015 .

[8]  Bengt Carlsson,et al.  Nonlinear and set-point control of the dissolved oxygen concentration in an activated sludge process , 1996 .

[9]  B. Carlsson,et al.  Estimation of the respiration rate and oxygen transfer function utilizing a slow do sensor , 1996 .

[10]  Robert Piotrowski,et al.  TWO - LEVEL DISSOLVED OXYGEN CONTROL FOR ACTIVATED SLUDGE PROCESSES , 2002 .

[11]  M. A. Brdys,et al.  Modelling and control of wastewater treatment plants , 1999 .

[12]  Niels Kjølstad Poulsen,et al.  Control of sewer systems and wastewater treatment plants using pollutant concentration profiles , 1998 .

[13]  Hyunook Kim,et al.  SBR System for Phosphorus Removal: ASM2 and Simplified Linear Model , 2001 .

[14]  Ronald Soeterboek,et al.  Predictive Control: A Unified Approach , 1992 .

[15]  M. R. Katebi,et al.  Predictive control of dissolved oxygen in an activatedsludge wastewater treatment plant , 2003, 2003 European Control Conference (ECC).

[16]  K. J. Keesman,et al.  Robust model predictive dissolved oxygen control. , 1995 .

[17]  S. Isaacs,et al.  An analysis of nitrogen removal and control strategies in an alternating activated sludge process , 1995 .

[18]  M. Nielsen,et al.  Optimization of a nitrogen-removing biological wastewater treatment plant using on-line measurements , 1994 .

[19]  Paul Lant,et al.  Multivariable control of nutrient-removing activated sludge systems , 1999 .

[20]  H. B. Verbruggen,et al.  Comparison of nonlinear predictive control methods for a waste-water treatment benchmark , 1999, 1999 European Control Conference (ECC).

[21]  Michael Johnson,et al.  Control and instrumentation for wastewater treatment plants , 1999 .

[22]  Bengt Carlsson,et al.  Iterative design of a nitrate controller using an external carbon source in an activated sludge process , 1998 .

[23]  Gustaf Olsson,et al.  SIMULTANEOUS DO CONTROL AND RESPIRATION ESTIMATION , 2002 .