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Show inexpensive. Ideally, an on-line "PIC Monitor" would be useful, but, to date, on-line continuous measurement of trace organics has not progressed outside the laboratory. Therefore, due to current technology limitations, any on-line performance indicator must use only measurement techniques available today at a reasonable price. The new proposed R C R A regulations may require monitoring of C O and/or total hydrocarbons (THC) on a continuous basis in all combustors burning hazardous waste. It seems appropriate to use these analyzers as the starting point for an on-line performance indicator. A typical hazardous waste consists of many different compounds but, in terms of an ultimate analysis, any incinerable waste would contain C, H, N, O, ash, plus a host of other compounds, such as heavy metals, halogens, sulfur, and phosphorus. Since incineration is combustion, the preferred end products are C O 2 and water vapor. However, due to fluctuations in feed composition, Btu content, or batch charging, transients can occur that have the potential to deviate from optimal combustion conditions. In this case, PICs can be created, with the predominant PICs being C O , unburned volatile and semi-volatile hydrocarbons (possibly halogenated, oxygenated, or nitrogenated), and soot, possibly containing condensed non-volatile organic material. Figure 2 illustrates these phenomena. While the original study4 used two indicators, the Unsatisfied Oxygen Demand (UOD)8 and Carbon Penetration (CP) to describe the incinerator performance, this paper will only present C P data. B y performing a carbon balance on the kiln, assuming that the unburned total hydrocarbons (THC) are emitted as methane and all soot is elemental carbon, a parameter dubbed Carbon Penetration (CP) can be calculated, which represents the fraction of initial waste carbon that was emitted as T H C , C O , or soot; that is, c p _ xthcmthc + x c o m C o + x p m p xwastemwaste (D where xthc, xco, and Xp, and x w a s t e represent the mass fraction of carbon in each species, and mthc> mco> ana^ m p represent the mass emission of each species, with m w a s t e being the mass of waste fed over the measurement period Complete Combustion C02 UNBURNED HYDROCARBONS (GASEOUS) CO SOOT (ELEMENTAL CARBON, NON-VOLATILE ORGANICS) Figure 2. Fate of Waste Carbon 5 V-28 |
