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Show burnout. The ACC system provides even steam flow and low emissions by controlling fuel feed and combustion air distribution while monitoring flame characteristics, flue gas temperature and composition (~). RILEY-TAKUMA MASS BURNING COMBUSTOR The Takuma Stoker shown in Figure 2, consists of four separate sections; feeder table, drying and ignition grate, combustion gra~e~ and burnout grate. Between the grate sections are two to three foot drops which reduce top to bottom fuel stratification and break up large agglomerations. Fuel drying, pylorisis, and ignition occur on the drying and ignition grate. About 95 percent of the fuel combustion occurs on and over the combustion grate. The burnout grate provides time for carbon burnout and reduction of putriscibles under locally high excess air conditions. The grate sections are comprised of reciprocating grates made up of parallel stepped grates. With every other grate stationary, the moving grates alternately drop behind and then project beyond the stationary grate. This action lifts refuse on the grate above the refuse just ahead causing a stirring action to provide better agitation and aeration to the refuse. Combustion air is fed and metered separately to each grate region; drying, combustion and burnout. Then the air for each region is fed separately to each parallel grate, as shown in Figure 3. Air valves are installed in every line to provide even air distribution and prevent air channeling. Conventional or non-partitioned air plenums cause most of the combustion air to bypass the grate center and travel upwards along the sidewalls. As shown in Figure 4, OFA is introduced at three locations downward over the drying grate from the front wall, horizontally over the combustion grate from the rearwall, and horizontally entering the upper furnace from the front wall. Flow patterns observed during cold D1130 2 |