DRYIT Semi-Continuous Tray Drier
Practical Action
Heating
For effective drying of the produce, warm (max 80 degree), dry, clean air has to be driven
through the drier. Hence the drier can utilise any medium grade heat source combined with a
heat exchanger and blower.
Most operational units outline an indirect (fuelled) thermostat heater blower, either diesel or
gas fired. One model that has been found particularly appropriate is the Benson-Jetaire Zeta,
with an output of 60KW (220,000BTU) and an airflow of about 1700 cfm.
Folded and
welded mild
steel sheet
Bolt to base
at back
Diverging
To suit
ducting
Bolt to base
at back
To suit
ducting
Straight
Figure 31: Diverging and straight connectors
Diverging connectors have been used in the past for their low-pressure loss. The alternative,
straight through connector shown would be a lot cheaper, without significantly increasing
pressure losses, but has not been tested.
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