The document presents a technical seminar on water purification using solar stills, detailing the process and benefits of utilizing solar energy for distilling water. It covers types of purification methods, explains the working and design of various solar stills, and outlines advantages and disadvantages of the technology. Key findings include improved productivity with increased ambient temperatures and innovative materials for cost reduction.

1. Under the guidance of
Santhosh K.G
Assistant professor
Mechanical engineering
M.I.T Mysore
A Technical Seminar on
WATER PURIFICATION USING
SOLAR STILL
Submitted by
Mohamed Shakeeb Ahmed
4MH11ME069
1

2. INTRODUCTION
• A solar still is a simple way
of distilling water.
• It uses solar energy to distill the water.
• It removes impurities such as salt and
other microbiological organisms.
2

3. Water Impurities
• Suspended particles.
• Dissolved inorganic salts.
• Dissolved organic compounds.
• Micro-organisms.
• Pyrogens.
3

4. Types of purification
• Distillation.
• Vapour compression.
• Reverse osmosis.
4

5. Benefits of Distillation
• It produces water of high quality.
• Maintenance is almost negligible.
• Any type of water can be purified into potable water
by means of this process.
• Wastage of water will be minimum.
5

6. Types of solar still
• Spherical solar still.
• Hemispherical solar still.
• Pyramid solar still.
6

7. Spherical solar still
7

8. Hemispherical solar still
8

9. Pyramid solar still
9

10. Working of solar still
10

11. Concept for making a good solar
still
• The cover can be either glass or plastic.
• Glass is preferable to plastic because most plastic
degrades in the long term due to ultra violet light
from sunlight.
• The use of the mirror reflector will increase the
temperature of the solar still basin.
• Sufficient Insulations of wool, thermocol, sealants
etc. must be provided inside the basin in order to
prevent loss of heat.
11

12. Estimation of water output
Estimate: 3.91 liters/𝒎 𝟐
/day
Q=
𝑨.𝑬.𝑮
𝟐.𝟑
A = Aperture area of the still in 𝒎 𝟐
E = Efficiency of the still usually taken as 50%
G = Global radiation energy in MJ/𝒎 𝟐(Approx. 18 MJ/𝒎 𝟐)
12

13. Advantages
• Free of charge sun energy (during sunlight it
eliminates 500 Watt electric consumption per one
hour of sunlight).
• There are no moving parts; it is therefore reliable and
almost maintenance free (cleaning is required
though).
• Water taste is claimed to be better since the device
act as a Solar Water Vaporizer and it doesn’t boil the
water (resembling rain water).
• Neutral pH is claimed (like rainwater), not like the
not neutral pH of steamed distilled water.
13

14. Disadvantages
• Low distillate output per unit area.
• Leakage of vapour through joints.
• High maintenance.
• Productivity decreases with time for a variety of
reasons.
14

15. Case study
Fig: 12 Array Solar Still System
1.
15

16. 2.
Fig: Flat Plate Solar Still
16

17. Conclusion
• It was found from the experimental analysis that
increasing the ambient temperature from 32°C to
47°C will increase the productivity by approximate
12 to 23%.
• It was observed that when the water depth increases
from 0.01m to 0.03m the productivity decreased by
5%.
• Solar still productivity can also increase by use of
reflector by 3%.
• Capital cost can be reduced by using different designs
and new materials for construction of solar stills. 17

18. THANK YOU
18