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A briquette (or briquet) is a block of carbonaceous smokeless fuel (flammable matter) which is used as fuel to start and maintain a fire. Common types of briquettes are charcoal briquettes and biomass briquettes. Briquettes are used for both domestic and industrial use, prepared from bituminous coal using a binder. Briquette production is a mature technology, and the technology associated with coal briquetting has been developed for almost 100 years.

Historically, briquettes (especially coal and coke briquettes) have been used for fuel for approximately 100 years. Traditionally, briquetting technology was established for developing countries to produce briquettes of local residues, for use in household cooking stoves and restaurants. Later, as the capacities of the machines increased, briquettes were used in industrial boilers to create heat, steam, and power for industry and power plants. Within the past three decades, briquetting has also found its way to households in industrialized countries as consumer logs for wood-burning stoves and fireplaces. However, with the advent of modern fuel systems, the use of briquettes has declined and use for these products is found most often in the operation of barbecue units. While still a marketable product for such use, briquettes as fuel (such as smokeless fuel) are not used often for domestic and industrial heating. In more recent years, as the focus on renewable energy has grown, the applications for briquettes have grown concurrently, as have different technologies and new applications.

The briquette has to be ignited from the bottom by burning wood. During ignition, the upper part of briquette, upon heating, emits volatile matter which is a mixture of carbon and hydrogen compounds and is a strong pollutant. The newly developed briquettes can be ignited from the top just by striking a match, and the volatile matter will be burnt away when it has passed the upper flame. The briquette should be coated with a thin layer of combustibles and oxidizing agent and, therefore, should be kept in a dry place lest moisture retards ignition.

See also: Briquette Binder, Briquette Manufacture.