Page 20 - Water Every Drop Counts

DESALINATION : AN EXPENSIVE CONVERSION

Drinking seawater straight is a bad idea. Apart from other impurities that can impact our health
adversely, the basic problem is that our body must expel the excess salt in seawater by urinating
more water than what it actually gains by seawater intake.

Desalination is the process that reduces the level of salt in
sea water in order to make it safe for human consumption.
If we could ever competitively, at a
A high energy intensity process makes large-scale cheap rate, get freshwater from salt
desalinization prohibitively expensive. Desalination can, water, that would be in the long-range
however, still be cheaper in many places than pumping interests of humanity which would re-
ally dwarf any other scientific accom-
water out of the ground, or, import it from somewhere else. plishments.
With water consumption rising at a pace much faster than – President John F. Kennedy
population growth, more and more communities stare at
the prospect of suffering water shortages in foreseeable
future. Overtime the demand for freshwater supplies will
drive prices higher, making desalination increasingly viable
and attractive.

Since the 1950s, researchers have been developing membranes that could filter out salt. Presently,
this membrane technique, also called “reverse osmosis,” costs half of what it takes to distill same
quantity of salt water.

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