Catalytic pre-mixed fibre burners

摘要

The performances of three pre-mixed fibre burners(maximum rated power: 30kW), based on the same FeCr Alloy porous support, were tested in a specific pilot plant. The first one was a commercial FeCr Alloy panel(the refernece burner); the other two were catalytically activated by depositoon onto the fibres of the LaMnO_3 perovskite, according to two differnet procedures: 'direct' and indirect route'. Teh latter, in which an LaAlO_3 layer was placed between the catalyst and the fibres to prevent deactivation, should by preferred for the presumably major stability and constant performance in the long term. The flue gas temperature, the NO_x, CO and HC flue gas concentrations and the emission intensity of the panel surface, were measured as a function of E_a(excess of air) and Q(specfic heat power). Besides, the operating combustion regimes(radiant, transition and blue-flame) were identified by direct observation of the burner surface. As compared to the non-catalytic burner, the two catalytic ones enabled, with nearly unchanged NO_x production, up to about 5 times lower CO and HC emissions, particularly in the radiant comnustion regime. As a result, a wider rangeability of the burner(down to about 10% of the maximum specific operating power, where non-catalytic burner failed), with environmentally acceptable flue gas compositon, was achieved.