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Show 2.2 Burner. The burner used for most of the experiments is a variable swirl device; Fig. 2 illustrates the burner and the associated supply lines. The burner is, in essence, a perforated can of length and diameter of 200 mm with an air-blast atomizer gun up the center of the can. The air supply to the can is from a split annulus with air rotating in opposite directions in each half of the split. The annulus segments are fed from a common 3" air line that divides into 2 pairs of (1.5") lines with each pair feeding one of the two annular segments. Butterfly valves provide proportional control to each annulus segment, and swirl from full clockwise to full anti-clockwise is obtained by altering the proportional division of air between the segments. The burner gases exit into the furnace through a refractory quarl of 45°. To fire the different fuels the burner gun is set up to handle air, methane, oil, CWS, and water (for flushing). Figure 2 illustrates the line arrangement. The oil and CWS (and flushing water) share the common central line up the burner gun; and the air and natural gas share the outer annulus as atomizing fluids. In operation the oil is used for preheating the furnace using air as the atomizing fluid. In preparation for feeding the CWS slurry, the slurry pumping system (described below) is started and, initially the slurry is fed straight back to the supply drum through the first CWS return line that by-passes the slurry flow meter. When the slurry is pumping satisfactorily the second CWS return valve is opened and the first is partially or totally closed to divert the slurry through the slurry flow meter. When the flow rate is about right for the test to be executed the methane line to the atomizing air is opened, the oil flow is stopped (maintaining the methane flame), the final valve between the CWS line and the burner is opened as the second CWS return line valve is closed |