Fuel briquette is available in colors like black & brown. On briquetting agro-waste of cellular nature, high calorific value and low cost fuel can be a good substitute for coal and wood. Waste can be converted into useful energy source with this and to evaluate the end product, typical proximate analysis is done of the basis of following-
- To decide on the suitability of waste materials and select a proper mix, they are tested for their chemical composition .
- Approximately 10 - 15 % moisture available in Dried Biomass material is suitable for briquetting. In case of higher moisture content in material, it needs to be dried (through sun or dryer) before use.
- To get the desired bulk density and size, material is chopped, screened and ground, and is transported pneumatically into storage bins. With this separation of the metallic and heavier particles is ensured along with unifying moisture content in the material. Air used is wet or hot as per the case for moisture control. The cellulose bonding in biomass, in this process collapses due to application of high temperature (200 o C) and pressure (1200 kg/sq.cm) & more thereby fluidizing the lignin.
- The moisture content in the material should be lesser than 12% for best results during compaction. Material from bin is discharged to the machine through regulated conveyors where it is compressed in specially designed dies. The compression raises the temperature of the material, softening some of the inherent binders in it, which come to the surface and bind the material together.
- Formed Briquettes are made available in shapes of pellets or logs, which are forced through tracks by cooling them under pressure for shaping properly.
- Cutting of cooled briquettes is undertaken followed by it is packaging or bulk storage in bags for use or shipment.
- Binder is not required in the entire process.