Wood Chip Production Waste for Wood Pellet or Wood Briquette Production

The production of wood chips as biomass fuel in cofiring of PLN's (Indonesia's state-owned electricity company) coal powerplants has been increasingly popular lately. Wood chip production is the easiest biomass fuel production compared to various biomass fuel products currently produced by the industry. The availability of raw materials is the main factor in the sustainability of production. The calorific value of wood chips depends on the species or type of wood used and its dryness level (water content). Hardwoods and low water content are ideal products for wood chips. And because it has a low bulk density of around 250 - 350 kg / m3, the transportation factor is another aspect that is very important for the delivery of wood chip products.

The particle size of wood chips has also been determined so that handling and storage are easier. To obtain the desired particle size of wood chips, screening is carried out after the wood trunk or pieces are chopped with a wood chipper machine. With these prerequisites, there are products that are rejected from the production process, namely wood chip products that are too large (oversize) and products that are too small (undersize). Products that are too large (oversize) can be returned to the chipper machine to be chopped again, but wood chip products with particle sizes that are too small (undersize) must be used for other things so that in addition to zero waste wood chip production, it can also provide additional income for the wood chip producer.

Small particle sizes such as sawdust from wood chip waste production can be used for the production of wood pellets or wood briquettes (pini kay briquettes). And even wood briquettes are more tolerant of slightly larger particle sizes because wood briquette products have a higher density than wood pellets, in addition wood briquettes can also be further processed into charcoal briquettes (sawdust charcoal briquettes). Wood briquettes themselves are commonly used in countries with four seasons, especially in winter for home heating. While charcoal briquettes (sawdust charcoal briquettes) are commonly used for BBQ, especially for Middle Eastern countries and Turkiye.

In the production of wood chips, it is estimated that biomass waste that is approximately the size of sawdust is around 20-25%, meaning that if wood chip production reaches 5,000 tons/month, the waste is around 1,000 - 1,250 tons/month. This is sufficient for the production of wood briquettes and sawdust charcoal briquettes. Meanwhile, if you want to produce wood pellets, especially for the export market, usually a production capacity of around 5,000 - 10,000 tons/month is needed. Of course, this cannot be done. In addition, the investment in equipment for the production of wood briquettes, sawdust charcoal briquettes and even wood pellets for this purpose is also much larger than the production of wood chips. This makes it more reasonable if the production of wood briquettes or sawdust charcoal briquettes is carried out by other parties. The other party will process the wood chip factory waste into wood briquettes, charcoal briquettes (sawdust charcoal briquettes) and because the complexity of production and equipment costs are also higher, it is natural that the profits obtained from processing this waste are also higher.

The world price of wood pellets, like palm kernel shells (PKS), has fluctuated a lot, and lately the price has tended to be low. Palm kernel shells (PKS) themselves are biomass fuels that are competitors of wood pellets in the global market but are cheaper because they come from one of the solid wastes of palm oil mills that are processed simply. With these conditions, coupled with the fact that it is very difficult to obtain adequate volumes of waste from wood chip factories, the production of wood briquettes (pini kay briquettes) or charcoal briquettes (sawdust chracoal briquettes) becomes a rational choice. In addition, the stable price of the two products makes it even more attractive to consider them.