Wood fuel gas producer – As we consider the implications of peak oil and rising oil prices, both new and older technologies are again under the spotlight. This excerpt from a publication over 100 years old illustrates how some technologies have not changed a great deal.

“In Fig. 349 we illustrate a wood fuel gas producer, the design of M. Roche, Paris, France, which brings out the possibilities of utilization of saw-mill waste, slabs, and sawdust, and the waste of woodworking mills for the production of power-gas.

It consists of a central furnace in which the fuel charge is burned and which is surrounded by a series of retorts. The fuel used is wood or wood-waste matter, and the products of combustion in the furnace F pass through the flue E and around the retort B. Fuel is fed to the upper part of this retort, which is sealed, and the gas is distilled off by the high temperature maintained. The only exit of the retort is at the bottom, and in travelling down through the retort the gases pass through the lower bed of fuel, which is at a very high temperature, being practically in a state of incandescence.

Any condensable gases or vapors in this part of the retort are broken up and fixed so that the gases which pass through the U– shaped pipe L to the holder K are in the condition of permanent gases. When wood is used as fuel the composition of these gases is about 18 per cent, carbonic acid, 22 per cent, carbon monoxide, 15 per cent, methane, and 45 per cent, hydrogen.

The calorific value of the gas is about 346 British thermal units per cubic foot. While this is quite high it should be remembered that it is generated by distillation, and is therefore free from nitrogen, which usually forms about 50 per cent, of the volume of producer – gas and it also contains a larger proportion of hydrogen. The products of combustion in the furnace F, after circling around the retort, pass out the upper flue H, through the opening in the damper I, and out the exhaust-passage J.”

Source: GARDNER D. Hiscox, 1907, Gasoline and Oil-Engines Including Producer-Gas Plants, NEW YORK, THE NORMAN W. HENLEY PUBLISHING Co. 132 NASSAU STREET 1907, Page s393-394

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