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need to add about 40% new energy
to get i00% new seawater into the
system. Our energy recovery system
is slightly more expensive than other
systems, but when operating a plant
for twenty or thirty years, the initial
investment cost is quickly recove-
red through lower operating costs.
Knowing that energy is a scarce re-
source, particularly in many areas
where there also is a water shortage,
this is a very strong selling point for
Q. Some people say that the disposed back into the sea, and you our company when constructing a
quality of water produced from need to design the brine disposal line build/own/operate project.
a desalination plant is not as so that the brine goes into an area
good as ordinary drinking where it has no effect on the coas- Q. Many developing countries
water. Is this true? If not, what tal environment. If you disperse the are facing huge problems of
is this criticism based on? How brine into an ocean current/stream, water supply. Can you help them?
is water quality rated? then the salt concentration will very
quickly dissolve into the open sea. Of course we can. As long as you have
This really is just a rumour. There In an open-sea environment this access to seawater, either through
are, in fact, many desalination plants will never be an issue. However, in a the coastline or through saline un-
that do not deliver drinking water. more enclosed area like the Arabian derground reservoirs, desalination
However, through desalination you Gulf or the Bohai Bay in China, this can fix your water problem. The main
can tailor-make the quality of the needs to be monitored more closely. challenge with desalination in deve-
water product exactly to the quality loping countries is, however, the lack
you want. After the membrane pro- In certain countries one is looking of energy. One needs about 3-4kWh
cess the produced water may actually into a non-discharge policy. In such to produce 1m3 of fresh water, and
be too clean. If the water is to be used cases, the brine can be used in the we unfortunately often see that the
for drinking purposes, you will need production of salt. This, however, lack of power is the limiting factor for
to re-mineralize it to achieve the adds to the cost of water production. desalination. Things are improving.
correct mineral balance required for For example, in
drinking water. India one can
now have a dedi-
From a safety perspective, there are cated power line
two hygienic barriers in a desalina- in most coastal
tion plant, so the chance of the water states, thereby
becoming polluted is actually lower making desali-
than with many conventional water- nation a reliable
supply schemes. water source. In
Sub-Sahara Afri-
However, the quality of the water ca, though, lack
produced through the desalination of power is still a
process depends on the design of the challenge.
plant. A desalination plant should
normally operate for twenty to thirty There is the pos-
years, and in order to guarantee both sibility of using
the quality of water AND reliable solar power for
operation, you need the desalination Q. Aqualyng is known for being desalination, but currently only for
solution to be delivered from a repu- among the best desalination smaller plants. Nevertheless, if you
table company that has built plants processes in the world. What is want the desalination plant to ope-
before. so special about the technology rate 24/7, the solar plant can only
you have developed? supply power as long as the sun
Q. What happens to the salt and shines, so it makes the operations
other materials extracted from About 90% of a desalination plant less predictable. Solar efficiency is
the water that has been desa- consists of standard equipment, so improving every day, so in the fu-
linated -- does it become some where companies can make a dif- ture this will become a more possible
sort of waste product that could ference is either in the plant design alternative.
cause problems? or in the energy recovery part of
the project. Aqualyng owns its own If you ask me, one of the best ways
The brine -- which is the name proprietary energy-recovery device Western countries can help to
given to the 60% of water from the -- the Recuperator. This is a sophis- advance developing countries is by
membrane process that does not tically engineered, valve-controlled offering them power and water -- so
become fresh water --will contain energy recovery system that reco- I encourage aid organizations to sup-
100% of the minerals/salts that were vers up to 98.5% of the energy in port desalination and power compa-
taken from the sea. Normally, this is the brine stream, meaning you only nies who want to work in this field.

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