Relationships between heating value and lignin, moisture, ash and extractive contents of biomass fuels

Various fuel characteristics, such as moisture, ash, lignin, holocellulose and extractive contents of different biomass species were determined on ash-free dry weight and extractive-free dry weight basis to find out relationship, if any, between ash and extractive content with the higher heating value. Moisture in biomass generally decreases its heating value. Ash and extractive content are two 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 raised the higher heating values of the biomass samples.