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Show can be harmfu l to thE Rnvironment because of their potential leachab::lty. Metal emission5 from the thermal destruction of metal contalnin£ waste is becomln~ of incrRaslng interest to EPA. The concern about health hazards Assoclated with metal emissions, both to the atmosphere and by l~aching int~ ground water frOM residuals, has led EPA to consicer taKing regulatory actions to restrict metal emissions from hazardous waste iy.cir,eratlCtYI. lr. particular, siYlce CC'Ylgress EY'lacted the 1964 RCRA AMRndments (Ref. 7) to ban land disposal of hazardous wastes, lncinera~ion will be used mCtre frec:;ueYltly tel Clspctse ctf the baYIY'.~d wastes al'tC the rRsidues from treatment of the banned wastes. Consequently, more trace metals from incineration will be released to the environMent. Tnus, EPA's regulBtory need to restrict metal emisslons from inclneration has become More important than ever before. To meet this obJective, EPA must first establish a~ information baSE relative to where Metals go, and in what form, during and after iy,ciy,er atic.l'., aY'!d wr.at de£ree clf cCIl"ltrctl is l'leeded. Because c.f tr,e variations in waste feeds, incinerator design and operating conditions and pollutlon control equipment efflciencies, metal partitioning processes ln an incinerator facility are very cOMple~. This paper proposes a p.,. .... El irnil'.ary rncldel cCtnce~t tc. al'.alyze metal part it iC'Y,ly,g phel',c.rneY,a duriY,~ cc.rnbust i Ctl',. The approach determines the behavior of Met~ls in t~E cornbustion chamber based on the equilibrium therm~dynaMic state of each metal at the prOJected w~ste feed and operating conditions. PARTITIONING ANALYSIS A~ shown in Figure 2, a number of phenomena playa role in determlnln~ the behavior of metals during incineration of met~l bearlng wastes. These phenomena include: Vaporization of metals from the waste EntrainMent of ash particles Condens~tion of metal v~pors Coagulation of particul~tes Wall deposition of vapors and p~rticulates Particle removal by air pollution control equipment. One of the most important of these phenomena is the vaporl~ation of metal &pecies from the burning waste. Most of the particles that are ~mitted are formed by condensation of vaporized ~pecies (Ref. 8). ~etals are present in the wastes as either small mineral inclusions in the larger organic matriw or elemental species incorporated into t~e structure of the organic compounds. As the organic material burns away, the metals ~re e~posed to the hot, oxygen depleted zone immediately adjacent to the particle. At this point the metal can take one of the 5 |