Algeria has experienced harsh
droughts over the past twenty years. The driest regions of the west have suffered
the most. Algeria has experienced increasing water stress due to growing
populations, industry, and water demands of each individual in dry conditions.
Drouiche et al. evaluates the future
of desalinization of both brackish and seawater in Algeria until 2015. After
plans to create more reservoirs were deemed inadequate, the Algerian Government
supported plans for large desalination projects. There are also plans to ship
water inland from existing coastal dams on the coast inland as water supply
from desalinization plants becomes available by the sea. Technology is
improving, and making it a more realistic option for supplying large amounts of
water around the world. 11 large desalinating plants have been built in
Algeria, and 5 more are underway.
–Darien Martin
Drouiche,
N., Ghaffour, N., Naceur, M. Hacene, M., 2011. Reasons for the fast growing
seawater desalination capacity in
Algeria. Water Resources Management 25, 2743–2754.
A century ago, a long drought began
and Algeria’s Minister of Water Resources planned for dams to pump water of the
foothills up to the High Plains. This would aim to relieve the problem of
denser populations collecting along the coasts. However, the reservoir levels
were sinking. After evaluation it was decided that reservoirs wouldn’t supply
an adequate increase in water due to negative predictions for little rainfall,
actual building of the dams, physical losses from dams, overuse of groundwater,
uneven distribution that would occur, and contaminated surface waters.
During the drought, 21 small
desalinization sites were assembled which worked to help people through the
drought. Future larger desalinization plans were then assessed and found to be
cost effective, and provide more water, over the long run, than new dams would
provide. Algeria has many coastal areas that would be able to utilize supplies
from plants locally. Other benefits include a virtually endless supply,
desalinization processes that don’t pollute waterways, and technology that has
advanced and become affordable. The Ministry of Water Resources plans to move
water supply from coastal dams inland to the High Plains, and then use the
desalinated seawater for the coastal populations.
Algeria started building
desalinization plants in 2003. These were mostly built by oil companies, and
used thermal techniques of Multi Stage Flash (MSF) and thermo-compression. The
Algerian government planned a new desalinization program. All plants were
planned under “Build, Own, Operate” contracts (except in Kahrama). This requires
that the same people who design the plants build and manage them, so that
plants built are less likely to experience operation glitches. The Algerian
Water Authority and the Algerian Energy Company built 16 large plants, 11 of
which are complete. Each produces 100,000 to 500,000m3/day. The new plants use reverse osmosis; except
for one in Arzew, and another being built in Hamma which both use Multi Stage
Flash. The largest seawater reverse osmosis plant is planned to be built in
Maqtaa. When all plants are complete, they will produce 1,461 m3/day of fresh
water. 70% of the produced freshwater is used for cities and homes and 27% is
used for industry. From 2011 to 2015, water supply coming from the sea is
expected to increase 2,433,000 m3/day, and supply from brackish water by
248,000m3/day.
Desalinization is a growing
possibility throughout the world. The world’s desalination capacity is growing
at a rate of 55% per year. It now has the capacity to produce 60 million m3/day
of desalinated water, and in 2015 is projected to grow to 100 million m3/day.
Now, 63.6% is made with a membrane process of reverse osmosis, and 34.8% using
thermal processes. Algeria, Spain and Australia have the highest rate of
desalination capacity growth in the world. Saudi Arabia, the US, and United
Arab Emirates have built plants to make the highest capacities of desalinated
water since 1945.
Algeria now has a plan underway to
become more resilient to its long droughts. Through an integrated plan of
transporting water from the coastal dams to highlands, and implementing
desalinization on the coasts, more water will be available to a growing
population, industry and water demand. In addition to this plan of 16
mega-plants, The Algerian government has been supporting this plan to secure
water availability to people by subsidizing higher desalinated water costs to
fix water prices.
0 comments:
Post a Comment