Coal

Coal as a fossil fuel has long been used for a variety of industrial and domestic purposes. The worldwide distribution and widespread availability of coal resources have been a major contributor to the economic growth of many countries, either directly through their own resources or indirectly through access to the international coal trade. Alhough coal usage has continued to increase, environmental concerns and changes in the political climate have begun to give coal an unfavorable public image. Increasing concerns about coal utilization as a contributor to greenhouse gas emissions, particularly CO2, have led to more intense questioning of the role of coal and a renewed search for alternative energy sources. Despite this coal will remain the second largest energy source worldwide in the next years and a key feedstock for other industrial usages. Coal has been thoroughly researched over the years to the point where all its characteristics and properties that make it such a versatile product are known. This chapter describes and summarizes the general knowledge acquired about coal in relation to its formation, worldwide resources and reserves, composition and properties, and all the characteristics relevant for describing the quality of a coal when it is used in the main conversion processes: combustion, gasification, and cokemaking