________________________________________________________________ | | | | | | | | 1 | 2 | 11 | 12 | 13 | 14 | |_________________|________|______|____|________________|________| | | | | | | | | Carbon | C | 1C | 2 | 2CO_{2} | 14.95 | | Carbon | C | 1C | 1 | 2CO | 14.95 | | Carbon Monoxide | CO | 2CO | 1 | 2CO_{2} | 12.80 | | Hydrogen | H | 2H | 1 | 2H_{2}O | 179.32 | | Methane | CH_{4} | 1C4H | 4 | 1CO_{2} 2H_{2}O| 22.41 | | Sulphur | S | 1S | 2 | 1SO_{2} | 5.60 | |_________________|________|______|____|________________|________| _____________________________________________________________ | | | | | | | | 1 | 2 | 15 | 16 | 17 | 18 | |_________________|________|_______|________|________|________| | | | | | | | | Carbon | C | 29.89 | 29.89 | 112.98 | 142.87 | | Carbon | C | 14.95 | 29.89 | 56.49 | 86.38 | | Carbon Monoxide | CO | 6.40 | 12.80 | 24.20 | 37.00 | | Hydrogen | H | 89.66 | 179.32 | 339.09 | 518.41 | | Methane | CH_{4} | 44.83 | 67.34 | 169.55 | 236.89 | | Sulphur | S | 11.21 | 11.21 | 42.39 | 53.60 | |_________________|________|_______|________|________|________| It will be seen from this table that a pound of carbon will unite with 2-2/3 pounds of oxygen to form carbon dioxide, and will evolve 14,600 B. t. u. As an intermediate step, a pound of carbon may unite with 1-1/3 pounds of oxygen to form carbon monoxide and evolve 4450 B. t. u., but in its further conversion to CO_{2} it would unite with an additional 1-1/3 times its weight of oxygen and evolve the remaining 10,150 B. t. u. When a pound of CO burns to CO_{2}, however, only 4350 B. t. u. are evolved since the pound of CO contains but 3/7 pound carbon. Air Required for Combustion--It has already been shown that each combustible element in fuel will unite with a definite amount of oxygen. With the ultimate analysis of the fuel known, in connection with Table 31, the theoretical amount of air required for combustion may be readily calculated. Let the ultimate analysis be as follows: _Per Cent_ Carbon 74.79 Hydrogen 4.98 Oxygen 6.42 Nitrogen 1.20 Sulphur 3.24 Water 1.55 Ash 7.82 ------ 100.00