REPORT OF THE GADGET PROJECT
SYSTEM OF SOLAR DESALINATION OF SEAWATER
Teacher: Lysiane Aubry DAMEN ALI
Year : 2008/2009 DAOUD Farouk
Sketch of two researchers
We are two major environmental researchers who is interested on the various environmental problems.
We put our knowledge for the benefit of the poor as the southern hemisphere countries which know a lot ofproblems. One approach we enable to found that there was huge problem with drinking water. That's why we try to build a system to desalinate seawater. Our next challenge will be to solve the problems of famine.
II) System for seawater desalination
1) Elements of the system
2) Figure with designating
3) Working ofinstallation
III) The main parameters
1) Greenhouse effect
2) The cylindro-parabolic reflector
THE ABSTRACT :
Targets of the technical study: - to invent an economical system which uses the
solar energy in order to desalinate water
- to optimize our system
- to be able todesalinate about 1 litre per hour
- a simple and cheap construction
Context of the study:
Nowadays we are trying to economize more and more energy. The use of solar energy for production of drinking water is a priority for many countries because the desalination of salted water through ordinary distillation is more expensive operation because it requires a lot of energy.
For poorcountries in energy and drinking water resources, solar desalination of salted water becomes an economical and social development stake.
System chosen: Systems with cylindro-parabolic reflector
The cylindro-parabolic reflectors are systems in a "U" shape. The cylindrical reflectors concentrate the sun rays on a glass receiver tube located along the focal line of the reflector.
Temperatures canreach the receiver 400 ° C and can generate steam. In California, the plants of several megawatts have been built and use cylindro-parabolic reflectors to recover steam and therefore to drive gas turbines. Our system will consist in heat our salted water to evaporate salt.
1) The solar energy received on Earth
The Earth is located 150 millions kilometres from the Sun.It delivers 1026 Watt continuously in the form of radiation and the Earth received 178 million billion Watt on its face enlightened or 350 Watt per m2 at the equator.
The solar radiation is electromagnetic radiation consisting of mainly:
• Visible light of wavelengths between 400nm and 800 nm ;
• Infra red radiation (IR) wavelengths below 400nm;
• ultra violet radiation (UV)wavelengths greater than 800nm.
Solar energy is one of the first energy used by humans (after muscular energy ). More recently, solar power, solar oven, solar water heaters, solar heating, solar photovoltaic cells have revived interest in a direct use of solar radiation
2) The value of solar distillation
During the fifties and sixties, desalination was a subject of environmental concernfor the authorities which convinced that the combination of population growth and rising living standards lead overall, and in the medium term, a situation of scarcity water. They have promoted important programs of research and development to explore the feasibility of a large number of processes theoretically apply. Finally only two have survived: the solar distillation and use of membranes(reverse osmosis, electrodialysis).
Meanwhile, during the same period, and because of global shortage, a policy of water resource management, their use and their protection has been designed and introduced gradually in most countries. However, there is enough in the world of serious shortages so that production of desalinated water (from seawater or brackish groundwater) practically marginally in...