Page 149 - Wastewater Solids Incineration Systems

116 Wastewater Solids Incineration Systems

STACK
PRIMARY
HEAT EXCHANGER
WARM AIR

FLUID BED
REACTOR VENTURI
REHEAT SCRUBBER
H.X.

COOLER/
SEPARATOR
FLUIDIZING AIR REHEAT AIR
SLUDGE INCINERATOR PROCESS SCHEMATIC
FIGURE 6.4 Primary and secondary heat exchangers in a fluid bed system.

heat exchangers are shown. Additional heat recovery, in the form of a waste heat
boiler, could be added to this basic system either upstream or downstream of the sec-
ondary heat exchanger, depending on the needs of the application.

4.0 HEAT RECOVERY TECHNOLOGIES

This section addresses the most common types of equipment and systems used for
energy recovery and reuse. Included are discussions of recuperative air preheaters,
plume suppression heat exchangers, economizers, thermal fluid heaters, and waste
heat recovery boilers.

4.1 Recuperative Air Preheaters
Fluidized bed combustion was commercially produced starting in 1963. Early units
required co-firing of fuel (oil or natural gas) to sustain combustion. To reduce the cost