Page 26 - Wastewater Solids Incineration Systems

List of Figures

Figure Page

1.1 Illustration of carbon cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4.1 Available heat versus exhaust temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
4.2 Available heat from sludge incineration versus percent excess air . . . . . . . . . . . . . . . 40
4.3 Theoretical temperature of the products of combustion versus the ratio of feed cake
energy input to feed cake moisture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
5.1 Various kinds of contacting of a batch of solids by air . . . . . . . . . . . . . . . . . . . . . . . . . . 49
5.2 Liquid behavior of gas fluidized beds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
5.3 Pressure drop versus gas velocity for a bed of uniformly sized sand particles. . . . . . 52
5.4 Entrainment of solids from different heights above the top surface of a
dense bubbling bed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
5.5 Geldart classification of powders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
5.6 Auxiliary fuel consumption versus sludge solid content at various wind box
preheat air temperatures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
5.7 The Puerto Rico fluid bed incineration plant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
5.8 A typical process flow diagram for a wet-ash system. . . . . . . . . . . . . . . . . . . . . . . . . . . 64
5.9 A typical process flow diagram for a dry-ash system . . . . . . . . . . . . . . . . . . . . . . . . . . 65
5.10 A typical cross-section of a fluid bed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
5.11 A typical cross-section of an MHF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
5.12 Multiple-hearth furnace process zones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
5.13 Typical multiple-hearth incinerator process flowsheet . . . . . . . . . . . . . . . . . . . . . . . . . 81
5.14 Shaft cooling air arrangement in an MHF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
5.15 Typical rabble arm arrangement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
5.16 A multiple-hearth furnace—RHOX flowsheet with regenerative heat exchanger . . . 89
5.17 A multiple-hearth furnace flue gas recirculation system . . . . . . . . . . . . . . . . . . . . . . . . 91
®
5.18 The GLASSPACK closed-loop oxygen enhanced vitrification process . . . . . . . . . . . . . . 93
®
5.19 Thermal energy balance for GLASSPACK application at North Shore Sanitary
District, Zion, Illinois . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
5.20 Typical process schematic for gasification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
5.21 Flow scheme of the SlurryCarb™ process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
6.1 Flue gas energy versus temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
6.2 Auxiliary fuel requirements for a typical fluid bed incinerator . . . . . . . . . . . . . . . . . 107
6.3 A fraction of flue gas energy required for combustion air preheat . . . . . . . . . . . . . . 108
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