Briquettes are a solid fuel prepared from coal dust and fines (i. e., finely crushed or powdered coal) by adding a binder and holding it under pressure.

The binder is commonly pitch or coal tar, but other substances and materials are also used. A briquette made with a pitch binder has the highest caloric value, exceeding that of any coal. The ash content is generally less than that of coal. Briquettes have been made from lig­nite coal dust and fines without a binder (only pressure being used).

Posted in Audel HVAC Fundamentals Volume 1 Heating Systems, Furnaces, and Boilers