Environmental Engineering Reference
In-Depth Information
Qfx ES plant-
specific energy
Preexisting facility-
specific energy
Element
switch out
5.0
4.0
3.0
2.0
1.0
0.0
0
50
100
150 200
Days of operation
250
300
350
FIGURE 16.7
Change in speciic energy consumption after installation of TFN membrane modules.
16.3.1.2 Performance Data: Cayman Brac—Energy Savings
The higher permeability of nanocomposite SWRO membranes in a properly designed
desalination system also provides the ability to operate at lower pressures, resulting in
energy savings to the plant owner when compared to other commercial membranes. At a
seawater desalination plant at Cayman Brac (one of the Cayman islands) in the Caribbean,
an energy saving of 28% when conventional SWRO modules was replaced with nanocom-
posite membranes and is visualized in Figure 16.7. A portion of this energy savings was
due to recovery of low lost over time on the existing elements from fouling; however, even
when compared with the projected performance of new conventional membranes, the sav-
ings were still >16%. Stability of those data has been maintained for slightly under 1 year
as of this writing.
16.4 Conclusions
In a quest to push the limits of membrane performance, researchers have reached across
various ields of inquiry to introduce the TFN membrane and advance its chemistry and
morphology. As a result of these efforts, TFN membranes have found new areas of appli-
cation and have continued to advance performance boundaries. Now in the early stages
of commercial application, end users are beginning to see the fruit of these researchers'
efforts in the form of lower-cost and higher-quality water in desalination plants world-
wide. As work continues, TFN membrane technology is expected to continue to improve
separation options in forward and pressure-retarded osmosis, water reuse, brackish water
treatment, and treatment of produced water from the oil and gas industries.
