Page 92 - Wastewater Solids Incineration Systems
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Combustion Technology 61
Basis: Excess Air 40%, Feed Rate 454 kgDS/hr (1,000 lbs/hr, 75% VS,
5,556 kcal/kg (10,000 btu/lb) VS, 1550 F Freeboard, Auxiliary Fuel HHV
10,500 kcal/kg (18,900 btu/lb)
500
450
400
350
300
250
200
150
100
50
0
18% 20% 22% 24% 26% 28% 30% 32% 34% 36% 38% 40%
1200F 1000F 800F 600F 120F
FIGURE 5.6 Auxiliary fuel consumption versus sludge solid content at various wind
box preheat air temperatures (kg/h 2.205 lb/hr; °C [°F 32] 0.555).
4.3 Ash Analysis
In designing a fluid bed incinerator, it is also important to evaluate feed material
for its ash chemical composition. Sodium and potassium chlorides have a low
melting point. Large quantities of these materials in the feed can lead to glassifica-
tion of the bed media. The bed media can become sticky, and agglomerates (or
clinkers) can form, which results in segregation of bed materials and eventually
defluidization of the bed. Furthermore, if the feed contains iron, phosphorus, and
