Abstract:
It is needless to say the importance of water in our day to day life. As water is the
scarcest commodity of 21 st century, it is very important to conserve every drop of it.
Nowadays most of the surface water bodies are polluted and ground water table is declining
at an alarming rate. So we need to focus more on the harvesting and conservation of rain
water to tide over water scarcity. Even though there are number of rain water harvesting
techniques, roof water harvesting has more potential to solve domestic water scarcity both in
terms of economy and quality standards. The main problem with the existing RWH system
is with its purification system as it is not accessible to frequent cleaning in order to prevent
the clogging by suspended impurities. Keeping this aspect in mind, a project work entitled
“Improvement of rain water purification system” has been taken up. The work includes
study of impurities coming from different roofing materials, testing of a screen filter with
actual rain fall condition and design of secondary filter such as sand and charcoal filter.
Physical analysis of raw roof water and filtered water is done in water quality analyser.
Suspended solids in the water samples are also tested by gravimetric method. The results
showed that impurities in rain water varies with roofing materials, however, the variation did
not show consistency. The upward screen filter was functioning with an average filtration
efficiency of 89%. Among the secondary filters incorporated, charcoal filter showed better
performance over sand filter. The project has succeeded in its objectives. It is hoped that the
developed rain water filtering system can be recommended to the house holds facing water
scarcity in Kerala.
