Analysis
Contents of carbon fixed
The content of carbon fixed in charcoal ranges from a minimum of 50% to a high of 95%, in which American charcoal consists mainly of carbon. The carbon content is usually estimated as a "difference", or all other components are deducted as a hundred percentages and it is assumed that what remains is the% of car voucher "pure" or "fixed". The fixed-carbon is the most important component in metallurgy, since the carbon fixed is responsible for the reduction of iron oxides in the cast iron during its production. But the industrial user, to obtain an optimal operation cast, must find a balance between nature brittle charcoal with a high content of carbon fixed and a stronger charcoal with a lower fixed carbon content, and higher volatile matter.


Ash content
The ashes are determined by heating a sample, by weight, until the red with access to air to burn completely all the fuel substance, leaving a residue called ash. These mineral substances such as clay, silica and calcium oxide and magnesium, etc.., Present for the original wood and collected, such as soil contamination, during the process.

The ash content in charcoal varies from about 0.5% more than 5%, depending on the species of timber, the amount of wood with bark included in the oven and the amount of contamination with dirt and sand. Typically, a good piece of charcoal has an ash content of about 3%. Char fine can have a high ash content, but if it is removed by sieving the material less than 4 mm, the remaining more than 4 mm can have an ash content of about 5-10%. Purchasers of course suspect charcoal, which is difficult to sell (and, unfortunately, to use).


Analysis of typical coal plant
To illustrate the extent of compositions that are in commercial coal plants, table 7 gives a list of compositions for samples at random from several kinds of wood and various kinds of methods carbonizaci6n. Usually, all wood and all methods of carbonizaci6n can produce coal plants that fall within the limits commercial.
Table 8 records variations in the composition of charcoal found in the kiln foundation of a large steel plant with charcoal of Minas Gerais, Brazil. All this had been manufactured using coal furnaces of the type of brick beehive. The wood was used, or mixed species of natural forest of eucalyptus or re-planted.