Converting Waste Agricultural Biomass into a Resource - UNEP

Solar-Biomass Hybrid Cabinet Dryer 39
Thailand, Commercial
Crop
Residue
Auxiliary Materials
Process
Equipment
Main Product
Rice, wood, coconut
Rice husk briquettes, wood chips, coconut shells
Solar PV
Gasification
Solar-biomass hybrid cabinet dryer
Heat for drying
Technical Description of Technology
Small-scale drying based on electricity, coal, LPG and other fossil fuels is
normally expensive. Moreover, combustion of fossil fuels emits greenhouse
and other gases. Solar drying is an attractive option to solve some of these
problems. However, an inherent problem of solar drying is that it depends
entirely on the weather and is not possible to use during nighttime. A hybrid
cabinet dryer with an automatic temperature control mechanism has been
developed at Asian Institute of Technology (AIT), Thailand for drying
agricultural products. The hybrid pairs a domestic gasifier stove (DGS),
developed at AIT, and a flat plate solar air heater to supply hot air for drying
products inside a cabinet. The technical specifications of the dryer are
presented in Table 2.1.
Size of Machine/ Production Capacity
Table 2.1: Technical specifications of solar-biomass hybrid cabinet dryer
SI. No. Parameter
Specifications
1. Solar Collector type Flat plate air-heating solar collector
2. Solar Collector size 2m x 2m
3. Drying chamber dimensions 2m (length) x 2m (breadth) x 1.95m
(height)
4. Drying chamber construction Bricks and mortar
5. No. of trays 16 nos.
6. Total tray area 14 m2
7. No. of doors for loading/ unloading 4 nos., two at each side
8. Stove type Natural convection cross-flow gasifier
stove
39 http://www.retsasia.ait.ac.th/booklets/Dissemination%20Booklets-Phase%20III/Tech%20pack-Drylow%20resl.pdf
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