Prototype Briquette gasifying stove
Richard Stanley and Kobus Venter October 2003
This stove is actually a natural updraft biomass gasifier. Conventional gasifiers are bottom lit and rising hot gasses needs to be drawn down assisted by some form of electric blower. By top lighting and using measured amounts of Primary and Secondary air, the result is a natural draft (Updraft)gasifier that expels volatiles and emission gases upwards without
The burn direction is downward, but the pyrolysis gases move upward. A layer of charcoal is formed on top and slowly moves down as the so-called "flaming pyrolysis"zone and the unburnt fuel below this
layer is heated and starts releasing volatiles which is ignited above this charcoal forming layer.
Precisely metered Primary air is fed in through the door and into the reaction. The volatiles are constantly being released lower down and is then mixed with metered amounts of Secondary air higher up, and it's this volatile mixture that results in a blue flame. The combustible volatiles are made up of mainly Carbon Monoxide, Methane and Hydrogen.
All components made from 3CR12(chrome based alloy)
Approximate weight: 15 kg
Approximate height: 450 mm
Approximate width: 300 mm