osmosis (RO) membrane processes are the workhorse of the desalination
industry. The largest RO plants in the world found in
the Middle East have capacities on the order of 62 million m3
per year or about 50 million gallons of fresh water per day.
RO plants can purify seawater or brackish water, however the
equipment configuration, membranes, and pressured used vary
depending on the source and quality of the saline water.
The process units in RO are typically spiral wound polyamide-based
membranes that operate at approximately 200 to 400 psi.
The high pressures are needed to overcome the osmotic pressure
of the saline water and produce a reasonable flux of clean product
water (see picture at right). In addition to the high
pressures which requires a lot of energy, fouling of the membranes
and their decomposition by chlorine are current problems of
research in reverse osmosis membranes entails the design, synthesis,
and testing of new polymer and polymer composite membranes that
could be applied to RO processes. We seek to increase
the flux of pure product water while decreasing the required
pressure. The materials we investigate are more stable
to chlorine treatments and in some cases may be foul resistant.
Our experimental work on new materials is supported by modeling
studies in order to better understand how to create membranes
with high flux and high salt rejection.
of reverse osmosis modules
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