Technology

Coal has been in use for hundreds of years as a source of energy by man. Apparently coal has been used for heating since the caveman. The new technologies invented during the industrial revolution provided coal with the real opportunity towards being the dominant worldwide supplier of energy due to the overwhelming need for energy. Mr. Watt, the inventor of the steam engine, used coal to power his engines which lead to coal being an important source of energy during the industrial revolution. Coal is formed as a result of decay of plants from primeval forests over a long time. It is less expensive than other energy sources and also one of the most abundant fuels. The United States has 25 of the worlds known coal reserves according to the National Center for Policy Analysis in Dallas, Texas. Traces of impurities like sulphur and nitrogen are found in coal. These substances are released into the atmosphere when coal burns thus creating acid rain. Coal burning also leads to carbon emission and eventually global warming. Emissions from coal burning are also known to cause respiratory diseases. Coal has the added disadvantage of being nonrenewablenon sustainable. Clean coal technology was started jointly by Canada and the US. Coal cleaning involves both simple and complex processes. Coal can simply be washed to get rid of pyritic sulfur. Smoke from burning coal can also be passed through flue gas desulfurization units that scrub away the sulfur from the smoke using limestone. Nitrogen oxides from nitrogen are taken care of by first preventing them from forming. This is achieved using staged combustion and catalysts. The fluidized bed boiler, yet another clean coal technology, eliminates sulfur and nitrogen oxides from coal by allowing limestone to mix with the coal and by burning at cooler temperatures respectively. The pressurized fluidized bed boiler is an improved version of the bed boiler. It has the capacity to spin a gas turbine and boil water for a steam turbine. Thus it is have two sources of electricity from the same fuel. Gasification of coal is the ultimate in clean coal technology. Impurities in sulfur are filtered out entirely. This technology also comes with the added advantage of using the hot combustion gases to spin a gas turbine and using the exhaust gases from the same turbine to heat water to steam and turn another type of turbine for even more electricity. With the above advances in coal technology, it is set to regain its stature as the worlds prime source for energy.