Modelling for Addressing Emerging Challenges of Urban Water Systems

Transcription

1 SANITAS Sustainable and Integrated Urban Water System Management Modelling for Addressing Emerging Challenges of Urban Water Systems Leading Edge Technology Conference, June 2013 Emerging Challenges for a Sustainable and Integrated Urban Water System Management Workshop Marina Arnaldos, Acciona Agua Celia Castro, Ghent University Fanlin Meng, Exeter University Usman Rehman, Ghent University Laura Snip, Technical University of Denmark

2 Modelling as a Research Tool Modelling is a critical tool in the integrated management of urban water systems Principal purposes of modelling in UWS: Design and optimization of complex processes and systems Acquire knowledge of intricate interactions Predict and evaluate system behaviour under different circumstances and scenarios 2

3 Emerging Challenge 1 Outline Decreasing Resource Availability: Increasing Need of Efficiency and Resource recovery Emerging Challenge 2 Higher Treatment Standards and Requirements: More Contaminants, Higher Treatment Quality Emerging Challenge 3 Increased Complexity in Tackling the Previous Issues: Need for Holistic Approaches Conclusions 3

4 Decreasing Resource Availability Resource Energy Chemicals Modelling Objective Effect of different operational strategies on energy consumption in MBR-RO systems (Michele Stefani, University of Girona) Optimization of aeration requirements in MBRs (Marina Arnaldos, Acciona Agua) Optimization of biogas production in anaerobic digestion (Kimberly Solon, Lund University) Effect of different operational strategies on chemical consumption in MBR-RO systems (Michele Stefani, University of Girona) Identification of cost-effective and recoverable draw solutions in FO- MBR systems (Marina Arnaldos, Acciona Agua) Nutrients Phosphorus recovery through precipitation (Kimberly Solon, Lund) 4

5 Selection of Draw Solutions (DS) for Forward Osmosis (FO) Systems Desirable DS characteristics: low cost, non toxic, resulting in high osmotic pressures and low internal concentration polarization Modelling of the mass transfer phenomena in the FO membrane is an effective way to select DS for further experimental research 5

6 Selection of Draw Solutions (DS) for Forward Osmosis (FO) Systems Results on how the fundamental properties of DSs affect water flux in the membrane and an optimal operation coefficient (taking into account reverse salt diffusion). This information has been used to select a set of best-performing salts for FO processes that had been overlooked by experimental research. 6

7 Emerging Challenge 1 Outline Decreasing Resource Availability: Increasing Need of Efficiency and Resource recovery Emerging Challenge 2 Higher Treatment Standards and Requirements: More Contaminants, Higher Treatment Quality Emerging Challenge 3 Increased Complexity in Tackling the Previous Issues: Need for Holistic Approaches Conclusions 7

8 Higher Treatment Standards and Requirements Pollutant Greenhouse Gases Phosphate and Sulfate Micropollutants Modelling Objective CH 4 emissions in sewer (Joana Batista, ICRA) CFD of N 2 O emissions in aerobic tanks (Usman Rehman, Ghent University) Plant-wide modelling of greenhouse gases (BSM2) (Laura Snip, DTU) N 2 O emissions in granular sludge reactors (partial nitrationanammox) (Celia Castro, Ghent University) Sulfide emissions in sewer (Joana Batista, ICRA) Phosphate and sulfate modelling in the anaerobic digester, plant-wide model of ph (BSM2) (Kimberly Solon, Lund University) Removal of micropollutants by membrane systems (Michele Stefani, University of Girona) Plant-wide model of fate of micropollutants (BSM2) (Laura Snip, DTU) 8

9 Modeling of GHG emissions in WWTPs using integrated CFD and biological models. N 2 O production depends upon local concentrations of DO, NH 4 + & NO 2-. Integrated modeling approach provides with local mixing & local concentrations of the components. 9

10 Velocity Plots at Different Heights in Bio-reactor 10

11 Gas holdup Plots at Different Heights in Bio-reactor 11

12 Emerging Challenge 1 Outline Decreasing Resource Availability: Increasing Need of Efficiency and Resource recovery Emerging Challenge 2 Higher Treatment Standards and Requirements: More Contaminants, Higher Treatment Quality Emerging Challenge 3 Increased Complexity in Tackling the Previous Issues: Need for Holistic Approaches Conclusions 12

13 Holistic Approaches Pollutant Optimization of UWS performance Modelling Objective Evaluation of economic, environmental and social impacts (Antonia Hadjimicael, University of Girona) Modelling the impact of the sewer system behavior on wastewater treatment (Ramesh Saagi, Lund University) Risk assessment of operational problems in UWS Smart and flexible effluent discharge regulation Risk Assessment / Mitigation of biological operational problems and GHG emissions (José Porro, University of Girona) Evaluation of UWS capacity to store, treat and discharge polluted water and subsequent development of flexible consenting approaches (Fanlin Meng, University of Exeter) 13

14 Smart consenting using integrated UWS models Environmental conditions (e.g. river flow rate and temperature) optimization UWS operations Improvement of surface water quality Cost-effectiveness Reduction of GHG emission Smart consenting should take account of environmental condition changes, and allow flexible operations to achieve surface water quality improvement in a sustainable way 14

15 Smart consenting using integrated UWS Effluent water quality is determined by the performance of the whole UWS models 15

16 Smart consenting using integrated UWS models CSO Wastewater Treatment Plant a. Valve operations Sewer system b. Pass forward flow threshold Overflow c. Flow to full treatment threshold d. Wastewater treatment operations Wastewater treatment process Overflow Storage tank Storm tank Effluent Receiving water body To improve surface water quality, operations in UWS need to be optimized in a holistic approach 16

17 Emerging Challenge 1 Outline Decreasing Resource Availability: Increasing Need of Efficiency and Resource recovery Emerging Challenge 2 Higher Treatment Standards and Requirements: More Contaminants, Higher Treatment Quality Emerging Challenge 3 Increased Complexity in Tackling the Previous Issues: Need for Holistic Approaches Conclusions 17

18 Conclusion Urban Water System (ESR 1,4, 7, ER 1): Need for Holistic Approaches - Optimization of whole-system performance Reuse Technologies (ESR2, ER2): Decreasing Resources - Energy Consumption MBR/RO H 2 S CSO WWTP (ESR 6,8,9,10): Higher Standards - Emerging contaminants - GHGs -Process Sewer System (ESR 5b, 7, ER3): Higher Standards - Combined Sewer Overflows - H 2 S and CH 4 emissions 18

19 Thank you! The research leading to these results has received funding from the People Program (Marie Curie Actions) of the European Union s Seventh Framework Programme FP7/ under REA agreement This presentation reflects only the author s views and the European Union is not liable for any use that may be made of the information contained therein. 19

20 Discussion How to go from controlled batch experiments to continous and dynamic WWTPs? How to generalize activated sludge from different WWTPs? Effect of oxygen and aeration on N 2 O production Pathways of ammonia oxidizing bacteria N 2 O production Biogenic/Non-biogenic production of GHG 20