A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES By P. Vega, F. Alawneh, L. González, M. Francisco, B. Pérez University of Salamanca (Spain) 6th European Congress of Chemical Engineering Copenhaguen, September 16-21, 2007

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES Motivation and Objectives The field of integrated process design and control has reached a maturity level that mingles the best from process knowledge and understanding of the control theory on one side, with the best from numerical analysis and optimization on the other Simultaneous approach to the design and control leads to significant economic benefits and improved dynamic performance during plant operation The Integration of Process Design and Control, bringing together the developments of a variety of design tools for the process design, has immense potential and advantages:  Reduce costs significantly  Reduce the iterations between separate design operations- like synthesis and control system design  Saves design time, and improves design efficiency Today's designers need to consider several critical parameters and objectives. Their interrelationships require design tools that can perform concurrent optimization which can only be accomplished when the tools are part of an integrated design-tool suite

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES Example of Tools: An integrated multi-objective design tool for chemical process design that combines the rigorous calculation of the BALAS process simulator and the interactive multi-objective optimization method NIMBUS presented en (Jussi et al., 2005) A tool for the uncertainty measurement in the integrated control and process design shown through a case study of how the control structure design is affected by measurement uncertainty and how the corresponding dynamic problem is defined and solved with rather regular tools presented en (Pajula et al., 2006) DePlan simulation software package as a method for integrated design management during the detailed design phase; DePlan integrates tow techniques, namely, Analytical Design Planning Technique and planning according to Last Planner, each involving a software tool proposed by (Chooa et al., 2004) Motivation and Objective The developed tool integrates various optimization algorithms and state of the art control systems that show high efficiency in the waste water treatment process control. With our integrated tool, the designer can consider several conflicting performance criteria simultaneously and find efficient design alternatives in a flexible manner

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES 1.Plant Structure Selection (Plant & Control) 2.Optimization Model Definition (costs, Controllability index, restrictions, etc...) 3.Optimal Design Parameters Calculations (plants, controller, steady state working point, etc..) AC AT Integrated Design Methodology Integrated Design Methodology considers that the changes in the process design might make the system more controllable. The methodology allows for the evaluation of the plant parameters and the control system at the same time The methodology that the support tool use combines the design of the plant, and the controller following a cost optimization procedure, with the desired closed loop dynamic as constraints

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES The cost functions include the investment, operation costs, and dynamical indexes (like the Integral Square Error (ISE)) The constraints are selected to ensure that the values of some controllability parameters, the H ∞ norm performance and many other performance criteria are within specified bounds The independent variable set includes plant dimensions, an operation point and the controller parameter This problem is stated mathematically as a NLP /DAE multi-objective optimization problem with non-linear constraints Integrated Design Methodology Construction Cost Operational Cost Data: q i, s i, x i, q sal To calculate: V 1, A, q r1, q p, s 1, x 1. Objective Function Subject to h(x)=0 g(x) <=0

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES Physical Restriction V1>0, V2>0 Operation Restriction Sludge Age, Mass Load, Waste Flow, Residence Time Integrated Design Methodology  Disturbance Sensitivity  ISE Controllability Restriction Mathematical Model Restriction

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES  Simulation Module  Integrated Design Module  User Case –Plant Design –Integrated Design –Different Optimization Algorithm –Various Cost Function Formulate –Various types of Controller (PID, MPC....etc) –Simulation with/without Faults SoftwarePackage Software Package The final Tool is an integrated one for optimization system which integrates: Programs for the optimization and predictive control of WWTP (Activated Sludge Processes) Simulators (SIMULINK) Computer Aided Control System Design (Matlab´s toolboxes) User Interface (GUIDE toolbox)

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES The user chooses the configuration to design: Plants without Nitrogen Removal (Manresa) Plants with Nitrogen Removal (Benchmark) SoftwarePackage>>SimulationModule Software Package >> Simulation Module Plant Selection Control System Selection Modify the Default Plant Faults Selection Simulation Parameters Results Simulate

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES Influent Tanks Operation Point Clarifier Operating Point Model Parameters Dimension Plant Selection Control System Selection Modify Default Plant Fault Selection Simulation Parameters Results Simulate SoftwarePackage>>SimulationModule Software Package >> Simulation Module

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES SoftwarePackage>>SimulationModule Software Package >> Simulation Module

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES Controller SoftwarePackage>>SimulationModule Software Package >> Simulation Module

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES Set faults type, fault time, and its magnitude (Toxicity Shock, Inhabitation, Bulking and Sensor faults SoftwarePackage>>SimulationModule Software Package >> Simulation Module Plant Selection Control System Selection Modify Default Plant Fault Selection Simulation Parameters Results Simulate

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES SoftwarePackage>>SimulationModule Software Package >> Simulation Module Plant Selection Control System Selection Modify the Default Plant Faults Selection Simulation Parameters Results Simulate

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES Plot and save the obtained results SoftwarePackage>>SimulationModule Software Package >> Simulation Module Plant Selection Control System Selection Modify the Default Plant Faults Selection Simulation Parameters Results Simulate

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES Design of the plants, Integrated Design (design of the plant and its control system), Type of control system to use (PID, MPC, etc…) SoftwarePackage>>IntegratedDesignModule Software Package >> Integrated Design Module Plant Configuration Control Structure and Type Optimization Algorithm Optimization Parameters Optimization Problem Modification Run the Algorithm Verification Results

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES The user can modify the optimization problem which load the default problem: Modify initial values, restrictions, simulation parameters, and optimization algorithm parameters. SoftwarePackage>>IntegratedDesignModule Software Package >> Integrated Design Module Plant Configuration Control Structure and Type Optimization Algorithm Optimization Parameters Optimization Problem Modification Run the Algorithm Verification Results

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES SoftwarePackage>>IntegratedDesignModule Software Package >> Integrated Design Module Plant Configuration Control Structure and Type Optimization Algorithm Optimization Parameters Optimization Problem Modification Run the Algorithm Verification Results

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES SoftwarePackage>>IntegratedDesignModule Software Package >> Integrated Design Module Plant Configuration Control Structure and Type Optimization Algorithm Optimization Parameters Optimization Problem Modification Run the Algorithm Verification Results

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES Parameter s SQPAGAG refined V (m3) A (m2) S1 (mg/l) ISE Cost Kp Ti Norm H  Simulation of the obtained plant, operation point calculation, dimension calculation, costs and controllability index calculation, compare results, save results SoftwarePackage>>IntegratedDesignModule Software Package >> Integrated Design Module

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES Save Results SoftwarePackage>>IntegratedDesignModule Software Package >> Integrated Design Module

Motivation and Objective Integrated Design Software Package Conclusion A COMPUTER BASED TOOL FOR THE SIMULATION, INTEGRATED DESIGN, AND CONTROL OF WASTEWATER TREAMENT PROCESSES The tool showed its efficiency as a support tool for Integrated Design or for the simulation of the process. It includes the most common optimization methods and suitable control systems for the activated sludge process. Using the tool make the Integrated Design process easier and friendly (easy data entry and getting results). Work is going on the improvement of this support tool adding more modules for the fault detection and diagnosis, control system design and synthesis calculations. Conclusion