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Mesocosm-Scale Constructed Wetland Design for Wastewater Treatment
Published on: May 2, 2025
Cost and effluent quality controllers design based on the relative gain array for a nutrient removal WWTP
Vinicius Cunha Machado1, David Gabriel, Javier Lafuente
1Departament d'Enginyeria Química, Escola d'Enginyeria, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain. vinicius.cunhamachado@gmail.com
Water Research
|October 10, 2009
Summary
This study designed advanced controllers for wastewater treatment plants (WWTPs), achieving significant cost savings. Implementing effluent quality and cost controllers reduced operating expenses by up to 13%.
Area of Science:
- Environmental Engineering
- Process Control
- Wastewater Treatment Technologies
Background:
- Wastewater treatment plants (WWTPs) require efficient control systems for optimal performance.
- Combined removal of organic matter, nitrogen, and phosphorus in A(2)/O configurations presents complex control challenges.
Purpose of the Study:
- To design decentralized effluent quality controllers and an automated cost controller for a simulated WWTP.
- To optimize operational costs while maintaining effluent quality standards.
Main Methods:
- Relative Gain Array (RGA) analysis was used to determine optimal pairings for control variables.
- Proportional-integral (PI) controllers were designed for ammonium, nitrate, and phosphate.
- A cost controller was developed to find the most economical setpoints for effluent quality controllers.
Main Results:
- RGA analysis facilitated the design of low-order, decentralized controllers.
- Effluent quality controllers alone reduced operating costs by 2.5% (€42,000/year).
- Combined effluent quality and cost controllers achieved a 13% cost reduction (€225,000/year).
Conclusions:
- Decentralized control strategies based on RGA are effective for WWTPs.
- Automated cost control significantly enhances economic efficiency in wastewater treatment.
- The developed control system offers substantial operational cost savings.
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