The device of the samovar
In some encyclopedias on housekeeping it is indicated that along with charcoal, the samovar can be heated with wood chips. In this recommendation, only a reservation is missing: for lack of coal. In wood, combustible elements are hydrogen and carbon, with volatile fractions in wood 85%, and solid - only 15%. Compared to charcoal, wood is more a dry gas than a solid carbon fuel. Wood (of course, we are talking about dry wood) burns in several stages.
The first phase is ignition. With the help of burning birch bark or larvae, the temperature of the wood is brought to 350 ° C.
The second phase is pyrolysis, that is thermal decomposition of organic compounds. In the pyrolysis of wood, which occurs at 450-500 ° C, in addition to charcoal, a number of volatile substances are formed: methyl alcohol, acetic acid, acetone, resins, etc. To prevent gases from escaping from the furnace without the use of a chimney, they must be burnt . Here, the main lack of wood as fuel is clearly manifested: pyrolysis gas evolution is an almost uncontrollable process. It requires an additional air supply, a space for mixing gases with air and then burning them. But neither one nor the other in the design of the jug of the antique samovar is not provided, and when the wood is burned with air, there is a large excess; The gases burn out already in the connecting pipe, so that it sometimes red-hot, and almost all the heat is simply lost. In the second phase, combustion products are formed - carbon dioxide and water.
Controlling the burning of wood by supplying primary air is possible only in the third phase, when burning a high-carbon solid residue, whose content is only 15%.
In Russia there was such a profession - charcoal, and charcoal was sold in strug kulaks. Its main consumer was ferrous metallurgy and other industry, including food industry.
In the cities charcoal was bought not only by blacksmiths and innkeepers. The antiques samovars and ordinary townsfolk warmed themselves. Carboniferous so actively transferred the tree to coal, that Tsar Alexei Mikhailovich had to prohibit this fishing around Moscow in order to avoid the complete reduction of forests.
Charcoal was a waste when burning a Russian stove. Before closing the furnace flap and pipe view, the unburned coals from the furnace hearth were swept out and placed in a tightly closed cast iron. Charcoal is very hygroscopic, besides being stored in significant quantities, it is self-igniting, because it is stored in a sealed metal container.