Fossil energy

Abstract

Fossil fuels are very diverse, because they are formed in different ways and have different states of aggregation (solid, liquid and gaseous). Every fuel has specific characteristics, as well as advantages and disadvantages. Solid fuels are most difficult to handle, and the milling, transportation, storage and ash removal after combustion procedures are extremely intensive. Hard coal is located up to a few thousand metres beneath the earth's surface. Conventional mining only goes up to a few hundred metres, however. Hard coal consists mainly of carbon, as well as hydrogen, oxygen, sulphur, nitrogen, water and ash. Lignite (brown coal) is mostly located close to the earth's surface and can therefore be mined more easily. It consists of about 50% water and has a lower heating value than hard coal. Crude oil mainly consists of various hydrocarbons, as well as nitrogen, oxygen, sulphur and small amounts of metal. Depending on its source, crude oil has a specific chemical composition that influences its physical properties, such as its viscosity and colour. © 2009 Springer Berlin Heidelberg.