Calculations and analyses are made for the ultimate composition of 158 Chinese power coals.The results reveal that the carbon content on as received basis,C ar ,increases linearly with the increase of the low heating value Q net,ar on as received basis;the hydrogen content on as received basis,H ar ,first increases with the increase of the volatile content on dry ash free basis V daf (V daf <33.0%)and then decreases(V daf >33.0%);the oxygen content on as received basis,O ar ,increases linearly with the increase of V daf ,ranging between 2.0% and 12.5%.By comparison,the nitrogen content on as received basis N ar of bituminous and lean coal is higher, while the sulfur content on as received basis S ar of anthracite is higher than bituminous coal,lean coal and lignite.The hydrogen on as received basis H ar is important for the conversion between low heating value and high heating value on as received basis for Chinese power coals,and S ar is important for the calculation of high heating value from the oxygen bomb heat value for Chinese power coals.
