To fully utilize the bamboo, another technology was generated that could help the standowners produce more income. Wastes from bamboo processing may be manufactured into charcoal briquettes. This could help reduce pressure on wood resource. It could also help mitigate carbon dioxide emission into the atmosphere.
The steps in making kawayan charcoal briquettes are:
1. Collecting and Preparing the Raw Materials
- Collect dead poles and branches from bamboo clumps. Oftentimes, these materials are left to rot or burned during clearing and cleaning operation of bamboo stands.
- Collect waste materials for use in making charcoal briquette. Bamboo processing leaves excessive waste materials such as trimmings and shavings. Generally, about 20-40% are thrown into waste when processing bamboo into furniture and engineered products.
- Collect chichacorn effluent. Collect and store in plastic containers the chichacorn processing effluent from the first and third washing of the boiled corn kernels. The first washing effluent contains 4. 48% TSS mostly lime while the third washing contains 3.08% TSS mostly starch.
2. Carbonizing is the process of converting the raw bamboo into charcoal. It can be done through drum method. Cool-off the charred materials in closed metal containers. An alternative to the drum is the pit method.
- Dig a small pit approximately 1m2 and 0.5 m deep and place the raw bamboo materials inside.
- Start lighting a fire into the wastes bamboo materials and then put rice hull little by little into it until the fire is gone and the wastes materials are completely charred and carbonized.
- Cool-off charred materials in metal containers.
- Shred or pulverize the charcoal to attain uniform sized particles. This will facilitate the even mixing of the binders and the charcoal fine particles.
4. Preparing the Binder – The use of chichacorn effluent as binders is recommended. It is cheap because it is considered waste material.
- Mix 2.5 L of effluent to one kg of charcoal. Where effluent is not available, use corn starch as a binder.
- Use 6% mixture This means that 1 kg of bamboo charcoal needs 60 g of gelatinized corn starch. The weight of water of the raw material.
- Mix thoroughly the binder and the charcoal.
- Mold into briquettes immediately.
6. Drying the Briquettes
- Dry the briquettes under the sun for 1-2 days.
- Continue drying under the shade until it reaches equilibrium moisture content.
- Pack the briquettes according to desired size and weight. For the 3.78 cm diameter x 4.88 cm length briquettes, approximately 40 pieces are equivalent to 1 kg. Wrap the briquettes with used cement bags, which could be used later to fire up the briquettes.
source: PCARRD-DOST, ILARRDEC, MMSU, photo from tradeindia.com