Final year project
Solar still- portable water
What is solar still?
A solar still distils water with substances dissolved in it by using the heat of the Sun to
evaporate water so that it may be cooled and collected, thereby purifying it. They are used in
areas where drinking water is unavailable, so that clean water is obtained from dirty water or
from plants by exposing them to sunlight.
Working principle of solar still
The sun's energy heats water to the point of evaporation. As the water evaporates, water vapour
rises, condensing into water again as it cools and can then be collected. This process leaves
behind impurities, such as salts and heavy metals, and eliminates microbiological organisms.
The end result is pure distilled drinking water.
The purification process involves two main processes including
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Evaporation
Condensation
Uses
Solar stills are used in cases where rain, piped, or well water is impractical, such as in remote
homes or during power outages.[1] In subtropical hurricane target areas that can lose power for
days, solar distillation can provide an alternative source of clean water.
Advantages
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Provide a maintained pH level which is very close to natural water as
compared to other water purifiers.
very cheap there is no cost of extra energy once you’re solar still is
manufactured you will get benefits without extra cost.
Less hazardous because there is no any mechanical equipment.
Works on free energy which we get from the sun hence there is a
record of Co2 emission.
Water taste is claimed to be very good if we compare it with other
purifiers
Disadvantages
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The solar still doesn’t break down the bacteria’s.
In solar still boiling process of water does not occur.
Sun still produces a low quantity of water.
It required time very much to produce less quantity of water.
Large top glass may attract the bugs and insects