Coal Briquette.

The coal briquette made up from raw coal material that comes from Indonesia's coal mining company. Raw coal material changes to briquette in several purification stages. In each successive stage, higher pressure and heat applied to the raw material to increase the carbon content and drive out more of its sulphur and moisture content. Pure coal material then grinded to make granular shape and ready to compressed into briquettes.

Scientists classify coal briquette according to its fixed carbon content, or the amount of carbon the briquette produces when heated under controlled conditions. Higher grades of coal have a higher fixed carbon content and lower sulphur content.

In Indonesia, coal briqutte classify in regular grade and super grade. Super grade coal briquette have the sulphur content nearly 0% (odorless coal briquette) but the price of that grade is about twice higher than the regular grade.

Coconut Shell Briquette.

The coconut shell briquette built up by the carbonization of coconut shell. Coconut shell derived from the copra industries. In Indonesia where coconut palms are grown on large plantations, copra (meaty inner lining of the coconut) is used mainly as a source of coconut oil. In copra indistries, the husk of coconut usually discarded, but the shell is carbonized to make coconut shell charcoal. Carbonization processing usually begins with partially burn the coconut shell in a metal drum for 4-5 hours. Coconut shell charcoal then grinded to make granular shape and compressed with 10 tons of hydraulic power into briquettes.