Converting Waste Agricultural Biomass into a Resource - UNEP

first using the drum method or the metal plate method before they were fed to
the grinding machine. These were placed inside the chopper to produce fine
carbonized materials. If the materials were raw (twigs, branches, corn cobs,
etc), the shredding mechanism was used. If the material was carbonized, the
grinding mechanism was used. If the materials were too wet, they could be
used for composting after shredding. The binder was prepared. The FPRDI
recommended cassava starch because it is readily available in the market.
The amount of starch used for carbonized charcoal briquettes was 6% to 15%
of the total weight of raw materials. The amount of water needed to gelatinize
the starch ranged from 60% to 100% of the total weight of raw materials.
Every particle of ground materials was coated with a film of binder to enhance
adhesion and to produce uniform good quality briquettes. Proper proportions
of ground materials and gelatinized starch were poured into the mixing
container. The ground materials were mixed with the binder thoroughly. Mixed
materials were converted into finished products using the manual or
mechanized briquettor. The mixture was poured into the molder which
transformed it into uniform sizes of briquettes. The briquettes were placed in
trays and dried under the sun for two days during sunny days or placed in a
suitable drier during rainy days. The dried briquettes were placed and packed
in plastic bags and were sealed. Charcoal briquettes were then ready for use.
For a simpler and laternative procedure:
1. Place the corn cobs inside the drum about 1/3 in height and burn until the
smoke disappears.
2. Fill the drum additional corn cobs (about 2/3 in height) and burn again until
smoke disappears.
3. When the smoke ceases, empty the drum.
4. Sprinkle water into the burnt corn cobs.
5. Spread the cobs for drying under the sun.
6. Separate the charcoal from the ashes.
7. Store.
Advantages to Developing Countries
Fumes from indoor cooking fires are responsible for more than 2 million
deaths every year in the developing world. But by simply turning their farm
waste into a cleaner burning fuel it may be quite simple to make that dire
statistic a thing of the past.
For more information, contact:
IRAD Science and Technology Information Institute
DOST Complex General Santas Avenue,
1631 Bicutan, Taguig City
Emal: science_ebooks@stii.dost.gov.ph
Sources:
1. http://www.mixph.com/2008/04/making-charcoal-from-corn-cobs.html
2. http://erdb.denr.gov.ph/enr/i4d/t4d_uf_briq.pdf
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