briquette

Some charcoal briquettes

Straw or hay briquettes

A briquette (or briquet) is a block of flammable matter which is used as fuel to start and maintain a fire. Common types of briquettes are charcoal briquettes and biomass briquettes.

Constituents of charcoal briquettes

Charcoal briquettes sold commercially for cooking food can include:^[1][2]

• Wood charcoal (fuel),
• mineral char (fuel),
• mineral carbon (fuel),
• Limestone (ash colorant),
• Starch (binder),
• Borax (release agent),
• Sodium nitrate (accelerant),
• Sawdust.

Some briquettes are compressed and dried brown coal extruded into hard blocks. This is a common technique for low rank coals. They are typically dried to 12-18% moisture, and are primarily used in household and industry.

Peat briquettes

In Ireland, peat briquettes are a common type of solid fuel, largely replacing sods of raw peat as a domestic fuel. These briquettes consist of shredded peat, compressed to form a virtually smokeless, slow-burning, easily stored and transported fuel. Although often used as the sole fuel for a fire, they are also used to quickly and easily light a coal fire.

Biomass briquettes

Biomass briquettes are made from agricultural waste and are a replacement for fossil fuels such as oil or coal, and can be used to heat boilers in manufacturing plants, and also have applications in developing countries. Biomass briquettes are a renewable source of energy and avoid adding fossil carbon to the atmosphere.

A number of companies in India have switched from furnace oil to biomass briquettes to save costs on boiler fuels. The use of biomass briquettes is predominant in the southern parts of India, where coal and furnace oil are being replaced by biomass briquettes. A number of units in Maharashtra (India) are also using biomass briquettes as boiler fuel. Use of biomass briquettes can earn Carbon Credits for reducing emissions in the atmosphere. Lanxess India and a few other large companies are supposedly using biomass briquettes for earning Carbon Credits by switching their boiler fuel. Biomass briquettes also provide more calorific value/kg and save around 30-40 percent of boiler fuel costs.

A popular biomass briquette emerging in developed countries is one which takes a waste produce such as sawdust, compresses it and then extrudes it to make a reconsistuted log which can replace firewood. It is a very similar process to forming a wood pellet but on a larger scale. There are no binders involved in this process. The natural lignin in the wood binds the particles of wood together to form a solid. Burning a wood briquette is far more efficient than burning firewood. Moisture content of a briquette can be as low as 4%, whereas green firewood may be as high as 65%.

Sawdust briquettes have developed over time with two distinct types: those with holes through the centre, and those which are solid. Both types are classified as briquettes but are formed using different techniques. A solid briquette is manufactured using a piston press which sandwiches layers of sawdust together and ones with a hole are produced using a screw press. The hole is simply a by product of the screw thread passing through the centre however it also increases the surface area of the log and aids efficient combustion.

See also

• Biomass Cook Stoves
• Charcoal
• Energy in Victoria
• Wood briquette

Notes

1. ^ Joe O'Connell. Kingsford Brand Charcoal Ingredients. California Barbecue Association website. Retrieved May 11 2007.
2. ^ All About Charcoal. virtualweberbullet.com. Retrieved May 11 2007.

External links

Wikisource has the text of the 1911 Encyclopædia Britannica article Briquette.

• www.briquetting.com
• How charcoal briquettes are made.
• Briquetting press - easy machine for briquetting biomass, like straw and hay.
• Legacy Foundation - created an appropriate technology briquette maker.
• Holey Briquette Gassifier Stove Development, Richard Stanley, Kobus Venter 14 August 2003 on BioEnergy Lists.
• Briquetting: An Answer to Desertification, Health Problems, Unemployment and Reforestation in Developing Communities - summary of 2003 seminar.
• Lucifer Logs - an interesting history of the two types of briquettes