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The wood gas generator produces ash and different kinds of condensed liquids. When handling these the health and environmental points must be noted. The ash is very fine and dusty. It contains fine charcoal dust which causes a risk of fire if removed when hot. The ash must be removed when the generator is cold. If ash is removed from a hot generator it must be placed in a steel box. In any case the ash must not be thrown to forest, field, road etc. because it can light a fire. The amount of ash produced depends on the need of power and type of fuel. If wood is used as the fuel 10 - 15% of it turns to ash. The ash collection box in the generator must be big enough to hold all the ash produced during the designed operating period and thus the ash can always be removed from the cold generator.

The amount and type of condensed liquids produced depends on the quality and moisture content of the fuel. Even if the liquids are produced from natural materials they include different kind of acids, alcalic components and even poisons. The liquids include water, ethylic acid, tar, aldehydes, ketones etc. The condensed liquids must be taken care of properly. They may not be poured to sewer or directly to nature. The best way is to soak them to cuttings and burn in campfire. The condensed liquids must be drained from 3 (4) draining plugs. When all the contents of completely filled fuel reservoir is used on the generator it creates condensed liquids as follows:

The condensed liquid must be drained also from the mixer if a draining plug exist. The ash must never be removed from the filter housing when hot. If the as removing hatch is opened oxygen enters the filter housing and ignites the glowing charcoal particles. This burns the filter fabric in a couple of minutes and the filter becomes inoperable. The charcoal dust collected inside the filter housing and spark trap is very fine and ignites easily. The ash must be removed when the equipment is completely cold and the worker must wear a dust respirator filter. The cold ash can be returned to nature. It can be used as fertilizer in fields or forests.