Abstract
A modified, bench scale cone calorimeter was used, at 50 and 70 kW/m(2) radiant flux, for the investigation of the gasification stage of two stage combustion of solid biomass. Pine and ash samples were investigated. The test material was supported on a load cell and contained in an air tight box, where the air flow was controlled to give an overall rich atmosphere equivalent to 1st stage gasification conditions. The gasification products flowed through the truncated top of the conical heater into a discharge duct where they were continually sampled through a heated line into a heated Temet Gasmet FTIR analyser. Secondary air was entrained after discharge from the duct, representing the lean second stage combustion in two stage biomass combustion. The total mixed product flow was used to determine the total overall heat release rate by oxygen consumption calorimetry. The primary zone showed flaming and char burning phases. Rich gasification equivalence ratios were generated depending on the fuel type and the gasification zone air supply. The optimum gasification stage conditions could be determined for maximum CO and hydrogen. The cone calorimeter was shown as a viable analytical method for determining the optimum 1st stage gasification conditions for different biomass fuels.