| Water
for the world
AquaLyng manufactures systems that
turn seawater into drinking water. To make these devices more efficient,
SINTEF scientists are working on an improved pre-filter.
| Contact:
Thor Thorsen, SINTEF Water and Environment
Tel: +47 73 59 24 36
email: thor.thorsen@sintef.no |
There’s nothing newabout using the
ocean as a source of drinking water in places where drinkable water
is in short supply. But Aqua- Lyng company founder Bjørn
Lyng wants to turn this idea into big business, and he has already
sold his systems to the Canary Islands, Egypt and Taiwan. Reverse
osmosis, the technique used in desalination plants, is also not
a new idea. But until now, systems based on this technique have
consumed a great deal of energy because conventional technology
is only able to create one litre of freshwater for every three litres
of seawater treated.
The remaining seawater, raised to a high
pressure as a part of the extraction process, is released via a
choke valve, wasting a lot of energy in the process. AquaLyng’s
improved technology is based on pressure recovery. A recuperator
recovers the lost energy, making the system much more efficient.
Lyng’s estimates show that energy consumption could be reduced
by more than fifty percent. However, several challenges remain before
the system is fully functional, which led the company to contact
SINTEF scientists.
FILTER
SINTEF has been working on membrane research and filtration since
the 1970s. For the past 20 years, the focus has been on the problem
of filter blockage by deposits. This is a common problem for membrane-based
systems – whether that system supplies drinking water in Norway
or feeds desalination plants in the Middle East. Small particles,
excluded by the filter by design, can coat the filter’s surface
and block it, reducing the capacity of the plant.
“In large desalination plants all
over the world, people solve this problem by installing large water
purification systems ahead of the pump that supplies the desalination
system itself,” says SINTEF’s Thor Thorsen.
“But placing a lot of equipment between
the sea and the high-pressure pump obviously means extra costs.
So in collaboration with SINTEF, Aqua- Lyng will attempt to develop
a simple filter that will be capable of such fine-scale filtering
that major additional installations will not be needed.” SINTEF’s
aim is to produce a good filter for AquaLyng for a tenth of the
price of currently available sub-micron filters. The project will
run until the end of 2005.
Åse Dragland |
