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Show 3 . 4 Furnace Load The furnace load and the ash melt area load are calculated as follows. Furnace Load 520,000Kcal/m3h Area Load 110Kcal/m2h 3 . 5 Material Balance and Heat Balance Figure 5 shows the material balance of melting bottom ash only (kerocene=70// h) and the mixture of bottom ash and fly ash, while Figure 6 describes the heat balance of the same. Melting bottom ash alone turned 8 8 % into slag, and fly ash from melting caught by the bag filter w a s 1%. With the mixture of bottom ash and fly ash, 8 6 % of the feed became slag, somewhat less than the case of total bottom ash, while fly ash from melting increased. This indicates the increases in the volatility as the fly ash is added, due to the larger amount of low-boiling point material(such as salts) in the fly ash. AiS to the heat balance, it is noticeable that the heat loss via exhaust gas in melting either feed stock is as high as 50-65%. This is because the heat balance w a s measured around the furnace, and the heat recovered by pre-heating combustion air is included in exhaust gas heat loss. The net loss, therefore, is 40-55%. Incidentally, the exhaust gas analysis of kerosene-rxurung surface melt furnace lists the following contents, on wet basis: C 0 2 = 10.2%, 0 2 = 3.1%, N 2 = 68.5% and H 2 0 = 18.2%. N O x was measured at 200ppm (corrected to 1 2 % O J Item © ® ® 0 Ash Slag Dust Combustion Gas, etc. Bottom Ash 100 88 1 11 Bottom Ash + 38%Fly Ash 100 86 6 8 © A s h rate Melting Furnace (4) Gas, etc. ©Collected dust ©Slag production Figure 5 Material Balance |