Fuelwood characteristics of six indigenous wood species from the Eastern Black Sea region

Various fuel characteristics, such as moisture, ash, lignin, holocellulose, and extractive contents of different parts of these species, were determined on an ash-free dry weight and extractive-free dry weight basis to find the relationship, if any, between ash and extractive content with the higher heating value (HHV). Moisture in wood generally decreases its heating value. Ash and extractive content are 2 important parameters directly affecting the heating value. High ash content of a plant part makes it less desirable as fuel, whereas high extractive content adds to its desirability. Again the heat content, which is a very important factor affecting utilization of any material as a fuel, is affected by the proportion of extractives present in it. Extractives raise the HHVs of the wood samples. In addition to higher lignin content, softwoods are considered to have greater HHVs because of their resin or extractive contents. The overall HHV among the species varied from 18.60 to 20.34 MJ/kg and the HHV on an ash-free basis varied from 19.33 to 22.01 MJ/kg.