Wood Combustion

1. WoodCombustion • Not used as much in the past. • Low cost / Low efficiency. • Poses some environmental concerns including: erosion and flooding form wood gathering, and the emission of carcinogens.

2. The Wood Cumbustion cycle-3 components nessicary : wood (fuel), air, and high tempretures • Moisture evaporates from the wood. So fresh or green wood does not make an efficient fuel. • Wood catches fire at 315 degrees Celsius. • The burn wood decomposes to charcoal and smoke. This material will combust at tempretures approaching 600 degrees. A duel combustion stove is required to do this.

3. Stove Design and Efficiency • In a standard fire place only the fist stage of wood combustion takes place and much of the chemichal energy in the wood goes out the chimney. • Tradtional fireplaces also pull in cold air from outside to replenish the air being consumed in the fire. Because of this some fire places have negative efficiencies. • To increase efficiency you can reduce the air intake by adding a glass screen in front of the fire. Or you can arrange the logs in way so that they burn more rapidly.

4. Dual Burning Stoves-By sending the smoke through a second “combustion area” we can extract more BTU's per unit weight of wood.

5. Cooking stoves in Developing Countries • This 3 stone stove is used for cooking in many develpoping countries. • Wood is fed into the fire and used to heat the pot for cooking.