Characteristics of Wood as Fuel

In 1943, about 64 million cords of wood were used as fuel in this country. Since fuel wood has the lowest value of any product from the forest, wood should not be used for fuel if other markets can be found. However, some inferior species and low quality trees with no other use should be cut and used for fuel to improve timber stands. As a fuel, wood is clean, it burns with little smoke or soot, it starts burning easily, it gives a quick heat, and it has a very low ash content. A farmer can produce a supply of fuel wood with almost no additional investment; by cutting wisely, he can also improve his wood lot. A disadvantage of wood as fuel is that it is bulky and heavy in relation to its heat content. Fuelwood in terms of heat value requires more man-hours for production than coal or oil. One pound of ovendried wood has a calorific value of about 8,600 BTU. The burning of wood is preceded by the evaporation of the moisture and the distillation and burning of the volatiles, and these processes require heat. For complete combustion, sufficient air must be supplied around or over the fuel bed. This air must be mixed with the gases given off by the wood while the gases are hotter than 1,100?F. More than 6 pounds of air is required to burn 1 pound of ovendried wood. To avoid condensation of creosote, it is best to burn dry wood in a small, hot fire. Recent improvements in wood burning include hopper type stoves and furnaces, pressure-formed briquets made from mill and planer wastes, and efficient use of wood chips as fuel in large installations.

You must be logged in to download any documents. Please login (login accounts are free) or learn how to Become a Member