Briquetting Biomass: The Green Alternative

We are recently forced to replace the burning of fossil fuels. The replacement of these non renewable resources with biological waste would reduce the overall pollution pressure on environment. The biomass waste like coffee husk, saw dust, rice husk etc can gathered and compressed into briquettes, these briquettes can also be transported and used as fuel to generate heat. It is high time to take this initiative to take initiative to use this biomass energy. Hence here you should take the initiative to convert the forestry waste and agricultural waste in to biomass briquettes, which can be used as a substitute for coal.

There are different machine available in market but those machine are bulky and are costly,Hence here we developing a portable, low cost briquetting machine, which makes use of simple Mechanism to convert the biological waste into useful briquette. Any waste or any proportion can be used but with proper binding agent. Some raw material do not require any binding agent if we use high pressure compression.

The end use of briquettes is mainly for replacing coal substitution in industrial process heatapplications (steam generation, melting metals, space heating, brick kilns, tea curing, etc) and power generation through gasification of biomass briquettes.

Raw material that can be used for making briquettes:
Biomass briquettes are a bio fuel substitute to coal and charcoal. Biomass briquettes are made from agricultural and forestry waste. The low density biomass (agricultural and forestry waste) is converted into high density biomass briquettes with the help of a briquetting machine. This machine makes biomass briquettes without the help any kind of chemical so this briquettes are 100% natural. The major raw material used for this is mustard stalks, Rice Husk, Coffee
 Husk, Coir Pitch, Jute Sticks, Sugarcane Bagasse, Groundnut Shell, Cotton Stalks, Caster Seed Shells / Stalk, Wood Chips, Bamboo Dust, Tobacco Waste, Tea Waste, maize stalks, bajra Cobs, Arhar stalks, Paddy Straw, Wheat Straw, Sunflower Stalk, Palm Husk, Soya bean Husk, Veneer Residues, Barks & Straws, Leafs, Pine Needle, Seeds Cases etc. Biomass briquettes are mainly used for thermal applications like in boilers, furnace and foundries, also for heating and melting purposes and heating in Cold areas and Hotels, Canteens, Cafeterias and house hold kitchen appliances etc.       

A popular form of biomass briquettes emerging in developed countries is called Sawdust Briquettes. It takes the waste by-product of saw mills such as sawdust, compressed it in the cylinder and is extruded out of the cylinder to make a reconstituted log that can replace firewood. The process is carried out in two phases i.e. with and without the binding agent. In the process of without binding agent the natural lignin in the wood binds the particles of wood together to form a solid. Burning a Sawdust Briquettes is far more efficient than burning firewood. Moisture content of a briquette can be as low as 4%, whereas that of firewood may be as high as 60%.

BINDING AGENTS:

Starch is the most common element but is usually expensive It doesn't have to be a food grade. In general, about 4-8% of starch is needed to make the briquettes. Starch sources can be corn starch, wheat starch, maize flour, wheat flour, rice flour, cassava flour, potato starch, etc. To use the starch as a binder, you must first gelatinize the starch, which is added to water and heated to form a sticky consistency, then adding to the mixer to be mixed with the charcoal powder.

Clay is almost available in every area and probably free of cost. A briquette contains almost 15% clay. It does not adds to the heating value. If too much clay is added then the briquette will ignite and it will not burn properly or not at all. Besides, clay will turn into ash after burning, which blocks the passage of radiant heat, resulting in the loss of heating value of the charcoal.

Molasses is the by-product of sugarcane industry. One ton of briquettes needs about 20-25% molasses. Briquettes binded by molasses burn well, but it has very bad smell during combustion. To avoid this a thermal treatment can be given known as curing.

Wood tars arises during the carbonization process and are recovered from stationary kilns and retorts. Pitch is a viscous liquid that remains after the distillation of coal tar. Tar is more liquid while pitch is more solid. Both of them require re-carbonization to avoid the emission of heavy smoke which may generate adverse health.