DRYIT Semi-Continuous Tray Drier
Practical Action
DRYIT – Semi Continuous Tray Drier
Preface
This manual is intended to assist engineering workshops that wish to construct a semi-
continuous tray drier based on Practical Action's design.
Practical Action has found that this drying system conveniently fills a gap between solar (and
assisted solar) dryers. These have a low throughput and are only suited to certain climates.
The larger industrial equipment is being used in seven developing countries drying a diverse
range of materials and Practical Action is currently pursuing a programme of greater
dissemination in Latin America.
Construction plans are available from Practical Action and have been successfully used both
in the UK and abroad. In some cases, however, workshops have had some difficulties, and
so it was thought appropriate to also develop a step-by-step manual to guide engineers
through the construction process.
The drier consists of a cabinet of trays, trays contain material to be dried, and the whole
system is connected to a thermostatically controlled heat source. Most commonly the
materials to be dried, are herbs, fruits or vegetables. However, the tray drier has also been
used to dry colouring materials and textiles.
It is hoped that this manual is helpful for construction and Practical Action welcome
comments or suggestions in regard to this manual. Drawings for a smaller tray drier (batch
drier) and a case study book are now available.
B L Axtell and A J Jones originally prepared this manual in 1995, it was revised in January
2004. If you require further information you can contact:
Practical Action
The Schumacher Centre for Technology and Development
Bourton-on-Dunsmore
Rugby
Warwickshire
CV23 9QZ
United Kingdom
T +44 (0)1926 634400
F +44 (0)1926 634401
E infoserv@practicalaction.org.uk
Or visit the Practical Action website at www.practicalaction.org to see what other projects
Practical Action works on.
Practical Action (formally known as The Intermediate Technology Development
Group) was founded by the late Dr. E.F.Schumacher. Practical Action enables
people in the Third World to develop using technologies and methods, which
give them more control over their lives and which also, contribute to the long-
term development of their communities.
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