Energy Magazine May 2015 | Page 17

THE SCIENCE OF NEW AND OLD ENERGY
that ensures the largest particle size is less than 75 millimeters . The coal is then screened to separate fine particles from coarser ones . Uniform particle size produces even combustion that is desired for kilns whereas coarser particles are used for grated applications . The next step , beneficiation , is the process whereby impurities are removed from the coal . The subsequent cleaning process helps separate out particles of stone since the coal is lighter . The final step is charring , which removes hydrogen and oxygen , resulting in a product that consists primarily of carbon .
The demand for natural gas has increased significantly in recent years

‘ The demand for natural gas has increased significantly in recent years as it offers an abundant , low cost energy source with comparatively low greenhouse gas emissions . ’

as it offers an abundant , low cost energy source with comparatively low greenhouse gas emissions . However , its use in electric power generation may be limited by the availability of natural gas pipeline transport systems . Natural gas is most often discovered in subterranean rock formations , usually near or in conjunction with coal beds or petroleum reservoirs . After a well is drilled and the gas is extracted , it is processed to remove impurities . Hydrocarbons and fluids must be removed to produce dry natural gas before it can be transported through major pipelines . A variety of equipment is usually installed at the well to carry out these purification processes . For example , a low temperature separator is used to remove oil and condensates from natural gas and flash tank separator-condensers
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