This document presents research on using novel impregnated membranes for wastewater treatment via forward osmosis. It outlines the objectives, provides an introduction to forward osmosis and different membrane types. Results show the impregnated membranes have lower water flux but higher performance ratio than commercial thin film composite membranes. While water flux is lower, impregnated membranes still have acceptable salt rejection and may be more efficient for wastewater treatment using forward osmosis.

1. Wastewater Treatment Using Novel
Impregnated Membranes in
Forward Osmosis
CE 498 Undergraduate Research
Ananthan Balachandran
May 8th, 2015

2. Presentation Outline
• Objective
• Introduction of forward osmosis in wastewater treatment
• Type of membranes
• TFC membrane, SW30 XLE membrane & impregnated
membrane
• Structure difference of membranes
• Research apparatus of forward osmosis
• Result
• Data for commercial membrane
• Data comparison
• Discussion
• Conclusion
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3. Objective
• Currently, the commercial membrane structure is
thin film composite membrane which has larger
water transport resistance because of the thickness.
• To determine whether the impregnated membranes
are suitable for the wastewater treatment using
forward osmosis.
• To determine the water flux and salt rejection of
the impregnated membranes in forward osmosis.
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4. Introduction
• Water becoming an scarce resource due to population growth &
economic development
• Lack access to clean water
• Methods of water filtration & purification
• Forward osmosis.
• Forward osmosis uses a semi-permeable membranes to get portable
water from the seawater.
• The driving force of forward osmosis is osmotic pressure difference
between draw & feed solutions.
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Figure 2:
Forward
osmosis
process
Figure 1:
Water
Filtration
APEC Water System. (2013). A Complete Resource Guide on Osmosis. Retrieved from Free Drinking Water: http://www.freedrinkingwater.com/resource-a-complete-resource-guide-to-osmosis.htm

5. Types of membranes used in Forward
Osmosis
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Figure 3: TFC membrane
(Commercial Membrane)
Figure 5: Impregnated
Membrane
Figure 4: SW30 XLE membrane
Reverse Osmosis Membrane

6. Thickness of the impregnated membrane & commercial
membrane
a) Impregnated membrane
b) Commercial membrane
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7. Research apparatus for forward osmosis
B
DE
A
C
Figure 6: Schematic of forward osmosis membrane test apparatus
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8. Coat the polymer on both side of the support, using ethyl alcohol as the solvent
Method to prepare impregnated membrane
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9. Result
Total Time (min) Salt Rejection (%) Water Flux (LMH) Salt Flux (gMH)
50 98.6 10.71 7.93
60 98.7 11.57 7.84
95 99.0 11.14 5.85
130 98.9 11.27 5.86
Theoretical Flux : 75.5 LMH
Experimental Flux : 11.1 LMH
Performance Ratio : 0.15
TFC Membrane from HTI ( Commercial Membrane)
Table 1: Data of TFC Membrane in Forward Osmosis
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10. Result
Type of membranes
Water Flux
(LMH/bar)
Expected Water
Flux (LMH/bar)
Salty Water Flux
(LMH/bar)
Performance Ratio Salt Rejection (%)
TFC 0.23 1.54 N/A 0.15 98.9
SW30 XLE 0.05 1.47 N/A 0.04 99.0
80 PEGDA 20
Ethanol
0.05 0.28 0.23 0.23 95.3
60 PEGDA 40
Ethanol
0.08 0.41 0.31 0.25 96.8
Comparison Between The Membranes
Table 2: Data comparison between commercial membrane, RO membrane and
impregnated membrane
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11. Discussion
• Water flux & salt flux in impregnated membrane is
lower because of concentration polarization.
-decrease the driving force
• The absolute water flux of impregnated membrane
is lower than the commercial membrane.
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12. Conclusion
• Impregnated membrane has higher performance
ratio and acceptable salt rejection although water
flux is lower
• The novel impregnated membrane has higher
efficient in forward osmosis in wastewater
treatment
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13. Questions?