General Description of the BSMs and of the Plant Designs Used

Transcription

1 IWA TG on Benchmarking of Control Strategies for WWTPs General Description of the BSMs and of the Plant Designs Used 10 September 2008 Vienna, Austria Dr Ulf Jeppsson IEA, Lund University Sweden 1

2 Outline Introduction Three Benchmark Simulation Models - BSM1 - BSM1_LT - BSM2 Sensors and actuators Evaluation principles Software platforms Conclusions 2

3 IWA Task Group members Dr Jens Alex, IFAK, Germany Dr John B. Copp, Primodal, Inc., Canada Dr Krist V. Gernaey, Technical University of Denmark Dr Ulf Jeppsson, Lund University, Sweden Dr Marie-Noëlle Pons, CNRS-ENSIC-INPL, France Dr Christian Rosen, Veolia Water, Sweden Dr Jean-Philippe Steyer, LBE-INRA, France Prof. Peter A. Vanrolleghem, Université Laval, Canada associated colleagues and friends 3

4 Short BSM history Idea first conceived in 1993 black-box plant simulation setup for control strategy competitions at conferences (similar to IFAC) Work initiated in 1997 as part of EU COST Action 682 and later in EU COST Action 624 Work task grew and gained momentum on its own IWA Task Group on Benchmarking of Control Strategies for WWTPs initiated in

5 BSM success story Books, chapters in books and PhD theses: 25 Journal publications: about 100 Conference presentations: about 100 Numerous technical reports BSMs distributed to >50 research groups world-wide Extremely verified computer models and platform independent results A complete tool-box of potentially stand-alone applications 5

6 BSM overall goals A realistic simulation benchmark platform for control strategy development and evaluation BSM1 & 2 A realistic simulation benchmark platform for development and evaluation of monitoring systems BSM1_LT Promote the development of control and monitoring strategies for WWTPs Promote the practical use of control and monitoring 6

7 Benchmark simulation protocol General WWTP layout Mathematical process models Influent wastewater characteristics Sensor and actuator models BSM1&2: allow for users to provide control strategies BSM1_LT: added sensor and actuator faults as well as process disturbances for process monitoring Simulation procedure Criteria and tools for performance evaluation 7

8 The Benchmarks No specific national or regional preferences Based on accepted models, e.g. ASM1, ADM1, 10-layer 1-D settler model Fully dynamic including noise Allow for high flexibility of control Reasonable input and plant behaviour focus is on relative comparison of control strategies Evaluation periods one week or one year 8

9 Benchmark Simulation Model no1 (BSM1) Five-reactor AS plant with secondary clarification Highly loaded system Three weather scenarios (dry, storm, rain) Performance during one week evaluated Updated evaluation criteria based on BSM2 development 9

10 BSM1 Long-Term (BSM1_LT) The original BSM1 system extended with: One year dynamics for evaluation period Influent wastewater based on BSM2 (after primary clarifier) Highly loaded system Time (temperature) varying parameters Sensor and actuator failures and disturbances (model based) Extented ASM1 model to include inhibitory and toxic effects Focus is on benchmarking of process monitoring algorithms Completely different evaluation criteria 10

11 Benchmark Simulation Model no2 (BSM2) BSM1 and BSM1_LT only allow for local control (monitoring) of an AS system Need for plant-wide ( within-fence ) evaluation Importance of sludge treatment Allow for supervisory long-term control strategies Include full plant process interactions Avoid sub-optimisation 11

12 Benchmark Simulation Model no2 (BSM2) Bypass Influent wastewater Primary clarifier HRT: 1h TSS: 3% modified Activated sludge reactors HRT: 14h BSM1 Secondary clarifier SL: 0.6m/h Effluent water Controllable flow rate Valve Thickener Gas TSS: 7% Storage tank HRT: 1d ASM/ADM interface Anaerobic digester SRT: 19d ADM/ASM interface Dewatering TSS: 28% Sludge removal 12

13 Benchmark Simulation Model no2 (BSM2) One year dynamics for evaluation period Increased activated sludge volumes Updated evaluation critera (now also in BSM1) Normally loaded plant Time (temperature) varying model parameters Seasonal and holiday effects included in influent Plant design closer to ATV and US EPA rules Considerable efforts to enhance simulation speed 13

14 Sensors and actuators Based on ISO 2003 norm (Rieger et al., 2003) All realistic sensors possible Defined by classes related to: - Noise level - Time response and delay - Lower & upper limits - Measuring interval Allow for measurements from lab analyses >60 control handles (actuators) to allow for flexible and creative userdefined control strategies (BSM2) Note: model-based generation of sensor and actuator faults and break-downs for BSM1_LT (Rosen et al., 2008) 14

15 IWA Task Group on Benchmarking of Control Strategies for Wastewater Treatment Plants Sensors and actuators Dr Ulf Jeppsson, 2008 General Description of the BSMs and of the Plant Designs Used 15

16 Evaluation principles (BSM1 & 2) Effluent quality index (BOD, COD, TSS, TKN, NO 3 ) Operational cost index based on: - Aeration energy - Pumping energy - Sludge production for disposal - External carbon - Mixing energy - Methane production and heating energy (BSM2 only) Risk index (based on foaming, bulking and rising sludge) Effluent limit violations, 95-percentiles and more Specific controller evaluation (e.g. wear-and-tear) BSM1_LT: specific process monitoring evaluation tools 16

17 Software platforms for BSMs BSM1: - WEST, SIMBA, GPS-X - Matlab/Simulink, Fortran - Partly: C, JASS, BioWin, STOAT, (AquaSim, EFOR, SciLab) BSM1_LT: - Matlab/Simulink, WEST, (SIMBA, Fortran) BSM2: - WEST, SIMBA, Matlab/Simulink, Fortran, (GPS-X) 17

18 Conclusions Protocol for objective benchmarking of control strategies and process monitoring methods BSMs ready and available (free) for general use IWA Scientific and Technical Report to be published in mid 2009, including CD with full BSM implementations Potential continuation via new EU-ITN project - Include other processes - Enhance existing models - Add sewer system and recipient models - Focus more on practical application 18

19 IWA Task Group on Benchmarking of Control Strategies for Wastewater Treatment Plants Thank You for Your Attention! Questions and comments? (also visit Dr Ulf Jeppsson, 2008 General Description of the BSMs and of the Plant Designs Used 19