PURO: reverse osmosis in a well

1. PURO: reverse osmosis in a well Bas Heijman 24 September 2014 1 Department of Water Management Section Sanitary engineering

2. Content • Introduction reverse osmosis • Brackish water: sustainable source for drinking water • Energy aspect of reverse osmosis • Is infiltration of concentrate sustainable? • Conclusions • Other research into sustainable drinking water production

3. Introduction reverse osmosis

4. Content • Introduction reverse osmosis • Brackish water: sustainable source for drinking water • Energy aspect of reverse osmosis • Is infiltration of concentrate sustainable? • Conclusions • Other research into sustainable drinking water production

5. Brackish water: sustainable source for drinking water

6. Nieuwe Maas 250m NAP deklaag -10 WVP ondiep -20 -30 scheidende laag -40 huidige RO-putten Reijerpark putten rivierzijde <150 mg/l -50 WVP diep -60 -70 150 – 300 mg/l -80 500 – 1.000 mg/l -90 300 – 500 mg/l >1.000 mg/l Brackish water: sustainable source for drinking water

7. Nieuwe Maas 250m NAP deklaag -10 WVP ondiep -20 -30 scheidende laag -40 huidige RO-putten Reijerpark putten rivierzijde <150 mg/l -50 WVP diep -60 -70 150 – 300 mg/l -80 500 – 1.000 mg/l -90 300 – 500 mg/l >1.000 mg/l Brackish water: sustainable source for drinking water Micropollutants Water > 100 years in sub surface

8. Brackish water: sustainable source for drinking water

9. Brackish water: sustainable source for drinking water • Option 1: discharge to channel • Option 2: discharge to sea • Option 3: infiltrate in the subsurface 2 1 3

10. Brackish water: sustainable source for drinking water • RO submerged in a well • Hydrostatic pressure about 7 bar • No feed pump needed • Cross flow pump: about 1 bar • Permeate pump: about 7 bar • Extraction brackish water above RO • Infiltration concentrate (2x) beneath RO

11. Feed 50 m³/h 8 bar Permeate 25 m³/h 0 bar + 7 bar +1 bar Concentrate 25 m³/h 7 bar>>0 bar Sub-murged RO +8 bar Normal RO Energy aspect of reverse osmosis

12. Energy aspect of reverse osmosis • PURO 40% energy savings compared to normal brackish water RO • Both RO’s calculated with 50% recovery • Substantial energy savings!

13. Is infiltration of concentrate sustainable?

14. Is infiltration of concentrate sustainable? • In “Westland” about 1000 RO installations for farmers with infiltration of concentrate • Province of South-Holland: no permits for farmers after 1013 • No alternative at this moment

15. Is infiltration of concentrate sustainable? • Decreasing fresh water reserve? • What is the water balans? • Faith of all the ions in the subsurface. Not only NaCl but also ions like As, Pb, Hg etc. • How does the concept fit into regulations? Province, Netherlands, Europe  • How does the concept fit into future regulations?

16. Is infiltration of concentrate sustainable? • At the same time: problems with salt intrusion:

17. Nieuwe Maas 250m NAP deklaag -10 WVP ondiep -20 -30 scheidende laag -40 huidige RO-putten Reijerpark putten rivierzijde <150 mg/l -50 WVP diep -60 -70 150 – 300 mg/l -80 500 – 1.000 mg/l -90 300 – 500 mg/l >1.000 mg/l Is infiltration of concentrate sustainable?

18. Conclusions • Brackish water is a sustainable source for drinking water because of the absence of micro-pollutants • PURO: 40% less energy consumption compared to conventional brackish water RO • Concentrate infiltration is necessary within the PURO concept • Concerns of concentrate infiltration important research topic

19. Content • Introduction reverse osmosis • Brackish water sustainable source for drinking water • Energy aspect of reverse osmosis • Is infiltration of concentrate sustainable? • Conclusions • Other research into sustainable drinking water production

20. Drinking with the wind • Several prototypes • Seawater: pressure 60 bar • Brackish water:pressure 15 bar

21. Drinking with the wind • 3th windmill/RO combi • Cheap drink water for 10.000 people in Somaliland • Drinkwater from brackish groundwater with RO • Direct use of wind energy (no electricity)

22. Ceramic filter pots • Desinfection • Point-of-use • Cheap • Local production • 22 factories

23. Ceramic filter Pots