Tubes containing membranes which filter salt water at
high pressure |
The
solution to one of the thorniest problems in the Middle East may be taking
shape on an anonymous-looking building site in south-west Israel.
Private contractors are building what they call a "water factory".
And they believe they may have found the Holy Grail, the Philosophers'
Stone: an economical way to turn sea water into high quality drinking
water.
It has become almost a cliche in the Middle East that the most divisive
issue is not land, not oil, but water.
In fact many experts believe water will be the cause of the next war in
the region.
So the prospect of limitless supplies of cheap drinking water has the
engineers here very excited indeed.
"Thinking about this concept of water factory, I think that the water
problems, not only in the Middle East, but in the rest of the world can be
solved, at comparatively competitive prices," enthused Gustavo Kronenberg,
one of the engineers in charge of the project.
"There is no problem of water, the problem is to get out the salt.
There is plenty of water in the sea."
But the real problem until now has been the cost. Water desalination
has been the technology of last resort, the Rolls-Royce solution for a
rich desert kingdom like Saudi Arabia.
New technology
Now this plant at Ashkelon, on Israel's Mediterranean coast, promises
to provide water at around $0.52 a cubic metre.
That's only marginally more expensive than the existing water costs in
Israel.
At the moment the water company provides supplies at around US $0.45 a
cubic metre. The water from the new plant will be higher quality, and
costs are coming down all the time.
HOW REVERSE OSMOSIS DESALINATION WORKS
1. Water flows in from the estuary or sea
2. Salt water contains sodium and chloride ions
3. Pressure is applied to force salt water through
membrane
4. Semi-permeable membrane with millions of
microscopic holes
5. Clean water fit for drinking
6. Saline concentrate flows out
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In fact
costs are going down so fast that the makers are even discussing building
desalination plants in rainy old England.
When it is finished next year the Ashkelon plant will produce 100
million cubic metres a year. That's roughly one seventh of the domestic
water demand in Israel (excluding agriculture and industry).
The key to the success is a technology called "reverse osmosis".
Essentially this involves water being pushed through a membrane or filter
at a very high pressure.
That high pressure means it uses a lot of energy. At the Ashkelon plant
they have cut the costs by building their own power station as part of the
unit.
New technology recycles spare energy as part of the process. The
membranes themselves are being continually upgraded to improve efficiency
as well.
International solution?
Already other countries in the area are looking at the technology with
interest.
Neighbouring Jordan is gasping for water. It is tenth from the bottom
of the world water league.
Supplies are being maintained, but only by plundering ground water, the
water stored deep beneath the earth.
And sooner or later that will run out. It would take just three plants
the size of Ashkelon to plug Jordan's current water deficit.
One idea being looked at is a massive pipeline up from the Red Sea to
the Dead Sea.
Part of the water would be used to replenish the Dead Sea, which is
receding at the rate of a metre a year because the surrounding countries
are using up the water that once fed into it.
More of the water from the pipeline could be cleaned, using the
technology being developed in Israel, then used to supply fresh water to
Jordan, Israel and the Palestinians.
A plan is now being
put forward to the World Bank, with a view to launching a major
feasibility study. But the ultimate cost could run into billions of
dollars.
The challenge is to secure that kind of political investment in the
region during the current political deadlock in the Middle East peace
process.
"From our experience, water is an element of peace-building and
co-operation," argues Jordanian Water Minister Hazem al-Nasser.
"All countries are ready to co-operate when it comes to water."
That's a very optimistic analysis of what's been one of the most
difficult questions in the politics of the Middle East.
At the Ashkelon water treatment plant, the engineer Gustavo Kronenberg
has a slightly different perspective.
"Unfortunately water is one of the reasons that create war. If you
compare the cost of one F-16, it is more or less the cost of this
desalination plant.
"I believe at the end of the day it will be much cheaper to solve
conflict based on this type of plant than through buying new F-16s."