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< prev - next > Manufacturing handicraft process industries Pottery and ceramics clay based tech book (Printable PDF)
5
The Clay
Refrigerator
5.1 Background
Food preservation is an
important issue in the
harsh climate of North
Darfur in Sudan. The heat
and dust take their toll on
precious crops. When you
have a good harvest it is
vital to keep produce in a
market saleable condition.
The clay refrigerator2
project was first initiated
by Practical Action in
2001 following research
conducted by Practical
Action Country Director
Pic 40. Practical Action
Project Manager Awad
Allah demonstrates the clay
refrigerator.
Mohammed Majzoub who had heard about the idea
being promoted by a teacher named Mohammed Bah
Abba in Nigeria. Following the successful experiments
conducted by Practical Action and Al Fashir University
to measure the clay refrigerators value in maintaining
nutrients and extending the shelf life of vegetables,
training was given to 21 ladies from the Al Fashir
Association for Earthenware Manufacturing on how to
make the cooler.
A lidded earthenware pot is fitted inside a larger pot
with an insulating layer of sand in between. This sand
layer can be kept cool by adding water at regular
intervals (generally twice a day), thus providing a
refrigerated storage space at minimal cost.
As water in the sand evaporates through the surface of
the outer pot, it carries heat, drawing it away from the
inner core, thus cooling the inside of the inner pot.
Most people living in rural
areas and many living in
urban areas for that matter
cannot afford to buy an
electric refrigerator and an
alternative method such as
the clay refrigerator can act
as an appropriate substitute.
The potteries association in
Al Fashir made and sold over
50 ceramic refrigerators
in 2007 which cost $20
Pic 41. Ladies gather to buy. The ceramic
around the clay
refrigerator has proved very
refrigerator during their successful and it has been
training course.
tested with a number of
different vegetables. For example tests have shown
that these foods can be kept fresh for the following
amount of time:
1. Tomatoes – 3 weeks
2. Bamiah - 2 weeks
3. Okra – 2 weeks
4. Rocket - 5 days
5.2 Instructions
1. The first task that needs to be performed is the
making of the moulds. To do this make a small
Pic 42. A stone is used to shape the inside of the mould
into a bowl shape.
2) There are a number of names in circulation for this technology including the zeer pots and pot in pot.
CLAY BASED
TECHNOLOGIES
15