Ignition of Fluidized Solid Fuel by Laser Radiation

This study investigates the ignition of pine sawdust (d < 200 µm) and mixtures of brown coal particles (d < 3 mm) and pine sawdust in a fluidized bed using local radiation from a continuous-wave semiconductor laser (= 450 nm) with a power of ≤23 W and with an exposure time sufficient for ignition and flame propagation over the fuel surface until self-sustaining combustion is established. The dependences of the time to reach self-sustaining combustion and the mass of sawdust completely burned within 60 s at a fixed radiation power on the air flow rate through the fluidized bed, the dependence of the time to reach self-sustaining combustion of sawdust on the radiation power at a fixed air flow rate, and the dependence of the time to reach self-sustaining combustion of a sawdust–mixture coal on the coal mass content (within 30- 80 %) at a fixed radiation power of 23 W are determined. The optimal conditions for self-sustaining combustion of solid fuel in a fluidized bed under the influence of laser radiation are identified.