Introduction:
Salaam Allah Alaykum “May the Peace of Allah Be Upon you”, my name is Ahmed,
I am from Algeria, I have been working as Financial man in the headquarter of the
Ministry of Finance in Algiers since 2003 just after have finished my bachelor’s
degree in this field, I am now student at the British Council in Tanzania (program
2103), such required long preparation period for English Academic purposes
after having been shortlisted by the Australian Aid authorities in order to study
Master in my field at their universities. The aim of this scholarship is to acquire
knowledges and improve my English skills which are strongly linked to
contribute in the development of the economy of my home country on return so in
this case I am interested in the shortage of drinking water in my country, such
big problem which occurs nowadays so you are welcome to support my topic above
by giving any suggestions, ideas or advice considered helpful to resolve this
issue.
The shortage of drinking water
in many areas of the world is now a serious problem. At least 80% of arid and
semi-arid countries, like Algeria, where 40% of the world's population live,
have serious periodic droughts. To resolve this crisis, different methods of
solar desalination have been used in several countries. Among these is solar
distillation — a process where solar energy is used to distil fresh water from
saline water for drinking purposes and other applications. The work on active
solar distillation system was carried out by many researchers. It is well known
that in solar distillation, the radiation from the sun evaporates water inside
a chamber at a temperature higher than the ambient. The principle of operation
is the greenhouse effect provided by the glass cover. Energy balances are made
for each element of still; solar time, direction of beam radiation, clear sky
radiation, optical properties of the cover, convection outside the still,
convection and evaporation inside are accounted. The most studied model is the
solar distiller, which has the following advantages: low installation cost,
independent water production at the point of use and no need for trained
maintenance staff. But it has important disadvantages, such as low efficiency
and problems associated with the deposit of salt, deposit of scale and
corrosion.
Algeria, like other southern Mediterranean countries, is enduring water
shortage which will get worse over the few next years. Algeria is known as the
country most severely threatened by water stress and scarcity by early 2020.
One of the important factors exacerbating this problem is the concentration of
three quarters of the inhabitants and consequently the industrial and
agricultural activities along the 1200 km coastal zone, which has led to an
increase in the pollution of the existing water resources. Droughts due to
climate change and pollution are the most important factors destabilizing the
existing balance. Therefore, the desalination of sea water can provide a
solution to one of the most urgent and vital and problems, of balancing and
enhancing water resources, as the wide variation of rainfall, from more than
2000 mm/y in the north coastal region dropping to less than 100 mm/y in the
southern Sahara, should be taken in account. Given these circumstances, we should focus on the need for desalination, the desalination program, and also the
strategy and the vision of desalination in addition to other non-conventional
water resources that might guarantee the optimum conditions for integrated
management and sustainable development.
To resolve this crisis,
different methods of solar desalination have been used in several countries.
Among these is solar distillation — a process where solar energy
is used to distil fresh water from saline water for drinking purposes and other
applications. The work on active solar distillation system was carried out by many
researchers. It is well known that in solar distillation, the radiation from
the sun evaporates water inside a chamber at a temperature higher than the
ambient. The principle of operation is the greenhouse effect provided by the
glass cover. Energy balances are made for each element of still; solar time,
direction of beam radiation, clear sky radiation, optical properties of the
cover, convection outside the still, convection and evaporation inside are
accounted. The most studied model is the solar distiller, which has the
following advantages: low installation cost, independent water production at
the point of use and no need for trained maintenance staff. But it has
important disadvantages, such as low efficiency and problems associated with
the deposit of salt, deposit of scale and corrosion.
