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Show The resulting Hazardous Waste Steam Generator Process is shown schematically in Figure 9. It is a three stage process. The first stage cools the combustion products from any combustion process by radiative heat transfer to a selected temperature. The next stage receives these gases and operates adiabatically within practical refractory schedule limits causing the gases' temperature to be essentially isothermal. The third stage receives the gases frcm the second stage and cools them by convective heat transfer to a selected temperature. The gases leaving the third stage in this system, enter a stack and are ducted to the atmosphere. The process is simple and all inclusive, not bounded by gas temperature, gas composition and source of combustion products. Figure 10 is a schematic of one design for the Hazardous Waste Steam Generator Process. It is a fired D type packaged boiler with a refractory lined section separating the radiation section frcm the convection section. The products of combustion after being cooled by radiative heat transfer, enter the thermal oxidizer which provides the residence time necessary to achieve the required DRE. Figure 11 is a plot of temperature versus residence time with the parameter DRE. The DRE values shown here represent an average of those values given in Figure 3. The fired water tube boiler curve represents a volumetric heat release of 100,000 Btu/hr-ft3. The reader should note that DRE curves are point functions and the boiler curves are real world events. Thus, an inconsistency is present in this figure which was constructed to describe in a meaningful fashion the various temperature-time combinations made available by the Hazardous Waste Steam Generator Process. The conventional fired boiler temperature-time profile is shown by line ®®© A denotes flame temperature at time zero, (B) the temperature of the combustion products leaving the radiation section at approximately 0.5 second, and (5) the temperature of the combustion products leaving the convection section at approximately 1.7 seconds. 5.8.19 |