Lignite, a low-ranking coal, is primarily used for electricity generation. It has a high volatile matter content and can be converted into liquid petroleum products and gases. Lignite has transportation and storage limitations due to its high water content and susceptibility to spontaneous combustion. It is not traded on the world market as much as higher-grade coal. Lignite mining occurs worldwide, and some environmental concerns relate to pollutant emissions from lignite plants.
Lignite is a black-brown fossil fuel that is primarily used for the generation of electricity. Considered a low-ranking type of coal, the fuel is usually classified by geologists as a recent fuel. Typically, it fits between peat and sub-bituminous coal on geological solid fuel classification scales. Lignite coal is burnable and may also be referred to as brown coal, earth coal or rose coal.
Geologically, lignite is believed to be of a relatively young age. Some geologists estimate that it was formed about 251 million years ago, during the Mesozoic and Cenozoic eras. In general, the fuel is thought to have formed from peat at shallow depths and at temperatures below 212°F (about 100°C). Distinguishable plant remains are often found in lignite. Additionally, the fuel often contains patterns of the wood from which it was made.
Lignite has a relatively high volatile matter content. As a result, it can be converted into liquid petroleum products and gases more easily than higher-grade types of coal, such as bituminous coal or anthracite. The fuel is also characterized by a high intrinsic moisture content, in some cases up to 75%. The ash content of lignite generally ranges between six and 19%, while the carbon content accounts for approximately 25% to 30%.
Brown coal can be more difficult to use than other types of coal. For example, it can be susceptible to spontaneous combustion, making transportation and storage problematic. Due to its transportation limitations, lignite is often burned at a utility plant that has been set up next to a lignite mine. The fuel’s high water content also makes it more likely to disintegrate, further reducing its value. Because of these limitations, lignite is usually not traded on the world market as much as higher grade coal.
There are a few main types of lignite, which are usually classified by structure. Xyloid coal, also called fossil wood or bituminous wood, has the fibrous structure of wood. Fibrous lignite often has a peat-like appearance and is approximately 50% water and 30% ash. Pitch lignite, on the other hand, is more like coal in appearance.
Lignite mining occurs worldwide in Europe, Australia, the United States and Russia. Brown coal production is more common in areas where other types of fuels are in short supply. Some environmental concerns relate to lignite mining because the pollutant emissions from a lignite plant are usually greater than the emissions from other types of coal-fired power plants.
Protect your devices with Threat Protection by NordVPN
