Presentation at the WEX2015 conference in Istambul about the next future on seawater desalination technology.

1. WEX 2015 February 23-25 IstambulWEX 2015 February 23-25 Istambul
FUTURE TRENDS IN
DESALINATION
Jorge J. Malfeito
R&D Director
Acciona Agua

2. WEX 2015 February 23-25 Istambul
Energy in RO Desalination

3. WEX 2015 February 23-25 Istambul
Efficient pretreatments.
 Development of simpler and more effective pretreatment
systems.
• DAFF
• DAF + energy-efficient ultrafiltration.
 Membrane fouling monitoring for operational optimization.
• Development of biofouling sensors for the optimization of RO and UF cleaning sequences.
• Developments on advanced control strategies.
Screens DAF Ultrafitration Reverse
Osmosis

4. WEX 2015 February 23-25 Istambul
Efficient RO process
 New developments on energy recovery devices.
 Low energy configuration and internal stage design.
 New developments on RO membranes: New materials.
• TFC: New monomers.
PTC (Pyridine-2,4,6-tricarbonyl trichloride) SDADPS (Sulfonated poly(arylene ether sulfone) containing
sulfonic acid and amino groups.
• Nanocomposite membranes:
 Biomimetic membranes
(aquaporin).
 Graphene membranes.

5. WEX 2015 February 23-25 Istambul
Low energy configuration and internal stage
design.
Adelaide, Australia
Capacity: 300,000 m3/day

6. WEX 2015 February 23-25 Istambul
New developments on RO membranes:
Aquaporin based biomimetic membranes.
 TFC aquaporin-based biomimetic membrane by
interfacial polymerization method, where
aquaporin-Z containing proteoliposomes were
added to aqueous MPD solution.
 Good mechanical stability when tested up to 10 bar
under RO conditions.
 High water permeability (4.0 L/m2 h bar).
 Test Conditions:
• NaCl rejection: 97%.
• P= 5 bar, 10mM NaCl Zhao, Y. et al. Journal of Membrane Science
423–424 (2012) 422–428

7. WEX 2015 February 23-25 Istambul
New developments on RO membranes:
Graphene nanocomposite membranes.
Membrane separation mechanism based
on two-dimensional channels formed
between the stacked between GO layers
deposited on TFC.
Goh and Ismail, Desalination. 356(2015) 115-128.
Performance of functionalized nanoporous
graphene versus existing desalination
technologies.
Cohen-Tanugi, D. Nano Letters 12-7(2012)3602-3608

8. WEX 2015 February 23-25 Istambul
Forward Osmosis Desalination.
• The draw regeneration process has a significant energetic disadvantage.
• FO process is not intended to replace RO.
• Applications:
• It appears best for forward osmosis research to focus fully on high salinity
applications (minery, oil & gas, shale gas, brine concentration).
• Applications that do not require draw regeneration, where reverse osmosis
cannot compete.
• FO for wastewater treatment and reuse?
McGovern, Lienhard; Journal of Membrane Sci. 469 (2014) 245–250
www.oasyswater.com
Comparison of two pass reverse osmosis with
forward osmosis assuming 47% efficiency for the
first RO pass and for draw regeneration.
(35,000ppm, NaClfeed at 50% recovery).

9. WEX 2015 February 23-25 Istambul
Membrane distillation
0% 1
10%
20%
30%
40%
50%
60%
70%
80%
90%
1.5
2
3
5
10
RO
MED/
MSF
100%
Recovery Ratio Concentration Factor
Input Feed Concentration NaCl at 200 C
0 40.000 80.000 120.000 160.000 200.000 240.000 280.000 320.000 TDS mg/l
memsys
VMEMD
A
B
 Achieves recovery rates resulting
in brine concentrations close to
saturation.
 Maximum achievable RR
decreases with higher salt content
of feed.
 Thermal evaporation/condensation process in which
a hydrophobic membrane separates liquid from
vapour phases.
 Temperature difference is the driving force.
 No droplet separator needed.
www.memsys.eu

10. WEX 2015 February 23-25 Istambul
Conclusions
 In seawater desalination, Reverse Osmosis is the
leading market technology.
 Seawater desalination is economical Today and will
become even more cost-competitive in the future.
 Long-medium term investment in R&D has the
potential to reduce the cost of desalinated water in
the next 10 Years.
 FO or MD processes are not intended to replace RO.
 These are suitable for high TDS contents.

11. WEX 2015 February 23-25 Istambul
jorgejuan.malfeito.sanchez@acciona.com