Hydrothermal carbonized coal
Hydrothermal carbonized coal (often referred to as hydrochar when produced from biomass, or as hydrothermally upgraded coal when applied to low-rank coals) is a product of a wet, moderate-temperature thermochemical…
Torrefied coal
This article describes the nature, production, distribution and significance of torrefied coal — an upgraded solid fuel produced by thermal treatment — and explains where feedstocks and conventional coal occur,…
Bio-coal
Bio-coal (sometimes called torrefied biomass or hydrochar, depending on the production method) is an engineered solid fuel produced from biological feedstocks that aims to match many properties of fossil **coal**…
Eco-coal
The term Eco-coal is increasingly used in industry and public debate to describe coal products and practices that aim to reduce environmental harm while preserving some of coal’s economic utility.…
Super-clean coal
Super-clean coal refers to coal that has been processed and treated to have very low levels of impurities and emissions-related constituents, or to naturally occurring high-grade coal that inherently contains…
High-rank coal
High-rank coal occupies a distinctive place among fossil fuels. Often associated with superior energy density, lower volatile content and a higher fixed carbon fraction, this class of coal plays specific…
Low-rank coal
Low-rank coals — commonly referred to as lignite and sub-bituminous coals — occupy an important but often misunderstood position in the global energy mix. Characterized by high moisture content, relatively…
Bituminous briquettes
Bituminous briquettes are a form of processed coal that combine the properties of natural bituminous coal with mechanical compaction and, often, added binders to create a solid, uniform fuel product.…
Anthracite briquettes
Anthracite briquettes are a concentrated, manufactured fuel derived from the highest-rank coal, prized for their high carbon content, low impurities and efficient combustion. This article explores the geology and distribution…
Ovoid coal
Ovoid coal is a term that can refer both to a particular morphological form of coal lumps and to the broader category of coal as a vital geological and industrial…
