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5.56 × 45 mm NATO bullet muzzle energy density [clarification needed] 0.4: 3.2: battery, Nickel–metal hydride (NiMH), low power design as used in consumer batteries [29] 0.4: 1.55: Liquid Nitrogen: 0.349: Water – Enthalpy of Fusion: 0.334: 0.334: battery, Zinc–Bromine flow (ZnBr) [30] 0.27: battery, Nickel–metal hydride (NiMH), High ...
Lignite mining, western North Dakota, US (c. 1945). Lignite is brownish-black in color and has a carbon content of 60–70 percent on a dry ash-free basis. However, its inherent moisture content is sometimes as high as 75 percent [1] and its ash content ranges from 6–19 percent, compared with 6–12 percent for bituminous coal. [5]
The rank of coal is correlated with its geologic history, as described in Hilt's law. In the ASTM system, any coal with more than 69% fixed carbon is classified by its content of carbon and volatiles. Coal with less than 69% fixed carbon is classified by its heating value. Volatiles and carbon are on a dry mineral free base; heating value is ...
It has the highest carbon content, the fewest impurities, and the highest energy density of all types of coal and is the highest ranking of coals. The Coal Region of Northeastern Pennsylvania in the United States has the largest known deposits of anthracite coal in the world with an estimated reserve of seven billion short tons . [ 2 ]
Its bank density (the density of a coal seam prior to breaking up during mining) is about 1346 kg/m 3 (84 lb/ft 3) while the bulk density of extracted coal is up to 833 kg/m 3 (52 lb/ft 3). [12] Bituminous coal characteristically burns with a smoky flame and softens and swells during combustion. [13]
Peat, a precursor of coal; Lignite, or brown coal, the lowest rank of coal, most harmful to health when burned, [7] used almost exclusively as fuel for electric power generation; Sub-bituminous coal, whose properties range between those of lignite and those of bituminous coal, is used primarily as fuel for steam-electric power generation.
Additionally, specific physical and mechanical properties of coal and particular carbonization properties The calorific value Q of coal [kJ/kg] is the heat liberated by its complete combustion with oxygen. Q is a complex function of the elemental composition of the coal [citation needed]. Q can be determined experimentally using calorimeters.
Sub-bituminous coal is a lower grade of coal that contains 35–45% carbon. The properties of this type are between those of lignite, the lowest grade of coal, and those of bituminous coal, the second-highest grade of coal. [1] Sub-bituminous coal is primarily used as a fuel for steam-electric power generation.