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Show THE SLUDGE SLAGGING COMBUSTOR APPARATUS A diagram of the sludge slagging combustor is shown in Fig. 1. This sludge slagging combustor has a vertical cylindrical configuration, and comprises, from the top, the swirling, melting, slag separating, and slag removing sections. The main features of this combustor are the use of swirling flow combustion and two -stage airinjection. Primary air is introduced from the top of the combustor through a swirler, and the secondary air is injected tangentialy into the upper portion of the combustor. The secondary air produces a stronger swirling flow pattern than does the primary aIr. On the other hand, primary air generates recirculating flow pattern in the center of the combustor which is able to hold the fine particles within the combustor and contributes to producing uniform temperature in the core of the combustor. The flow pattern in the combustor is controlled by manipulating the primary to secondary air ratio in order to maintain a high -slagging rate in the combustor. The sewage sludge ash is mixed with the primary air upstream of the swirler and is carried by the swirling flow from the top of the combustor and dispersed uniformly. Due to the centrifugal force, it collides with the wall of the combustor. Additional fuel is added in order to maintain the wall temperature of the combustor uniform at approximately lOOt higher than the ash fusion temperature. The sewage sludge ash melts Quickly after entering the combustor and trickles down the combustor wall and is discharged from the bottom of the combustor. A highly-erosion resistant refractory is used in the furnace. The furnace is water -cooled to produce a temperature gradient in the refractory, and the selfcoating effect of slag extends the life of refractory. Carbonized sludge Burner 0 Cooling water exit .- Exboust gas 0 Q Slag o Secondary air FM sensor Fig. I Schematic of SLUUliE SLI\lili I Nli C OMUUSTOIl - 2 - |