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Show refractory materials0 0 o 0 o o o o o o 0 o o 0 o o 20-30% With the testing furnace, ® and © worked together to produce 280//ash ton. With the existing furnace, the new burner was installed, and partial changes in refractory materials were made, but the shape of the furnace itself could not be modified. Its improvement corresponds with the high improvement value of item © of the testing furnace. b) Improvement in the gas burner Gas burners with three different flame shapes as shown in Figure 4 were installed in the test furnace, one at a time, and burned L P G equivalent of 60, 70 and 80/ kerosene to check the combustion characteristics. The product melted was bottom ash alone. The test results as expressed by the amount of fuel burnt against meltingunit according to the various burner indicated that the local-heating w as the best, followed by the split flame and the flat flame type. The best meltingunit w as obtained at 80/ equivalent of kerosene, and the meltingunits were 230, 260 and 270/ per ash ton, respectively. These exceeded the result usingkerosene burner (280/ per ash ton). Although natural gas has radiativity 10% lower than fuel oil, it showed 8% lower fuel cost at the test. This m a y be attributed to the lower unburnt loss of the gas at the tip of the flame when it hits the ash melting surface, the height of which varies as new material is pushed onto the melt. Type of Burner Local-Heating Flat Flame Sprit Flame Characteristics • Thick, short flame flow along bumertile • suitable for heating local area with convection • Thin flame spreading along bumertile and furnace wall • Suitable for heating bumertile and furnace wall surface evenly with reflection • Flame radiating from bumertile • Somewhat in the midpoint of Local Heating and Flat Flame types Outline of Flame w Figure 4 Comparison of gas burner 8 |