LOCAL TEMPERATURE AND WALL RADIANT-HEAT FLUX MEASUREMENTS IN AN INDUSTRIAL-SCALE COAL FIRED BOILER

This paper reports measurements of local gas temperatures and wall incident radiant heat flux in an 80 MW(e) pulverized coal corner fired boiler. Spatially resolved gas temperatures were measured using a 4 m long, triply-shielded suction pyrometer and total wall radiation was determined with an ellipsoidal radiometer. The data include detailed wall radiant heat flux measurements made around the periphery of the boiler at six different elevations. Local gas temperature profiles were measured at four axial positions in the boiler, with special attention to the near-burner region. Boiler operational data and coal proximate, ultimate and particle size analyses are also reported. Local gas temperatures in the boiler reached a maximum of nearly 1800 K near the burners and decayed to 1250 K at a position just above the boiler nose. In the burner plane gas temperatures varied from 600 K near the wall to 1800 K at the centre of the flame. Wall incident radiant heat fluxes varied between 440 kW m-2 in the near-burner region to 100 kW m-2 near the boiler nose. The radiation transport to the wall was observed to vary substantially around the periphery of the boiler, especially in the near-burner regions.