coal classification | Types & Facts | Britannica
Coal classification, any of various ways in which coal is grouped. Most classifications are based on the results of chemical analyses and physical tests, but some are more empirical in nature. Coal classifications are important because they provide valuable information to commercial users (e.g., for power generation and coke manufacturing) and to researchers studying the origin of coal.The Types of Coal: Composition, Usage, and Energy Value,Jan 29, 2020· Coking vs. Steam: Coking coal, also known as metallurgical coal, has low sulfur and phosphorus content and can withstand high heat.Coking coal is fed into ovens and subjected to oxygen-free pyrolysis, a process that heats the coal to approximately 1,100 degrees Celsius, melting it and driving off any volatile compounds and impurities to leave pure carbon.Lignite - an overview | ScienceDirect Topics,Brown coal reserves in the GDR fuel balance now amount to nearly 20 × 10 9 tonnes. Because of the lack of “hard coal”, more than 90% of the GDR's primary energy is produced from brown coal. Brown coal is used for purposes that traditionally used “hard coal”, for example, the metallurgical industry, heavy chemistry, railroad transportation.