Residue thermal waste treatment

Table 9.6 compares the residues from thermal waste treatment with respect to their long-term behavior. This assessment is usually made using leach tests in Table 9.6, the Swiss Technical Rule limits for residuals requiring a leach strength of pH 4 were used (Anonymous 1990 see Section 9.5.3). Tests have shown that the untreated and even the scrubbed electrostatic precipitator (ESP) filter residues do not meet these limits, and even the zinc content of ESP filter residue solidified with cement is only slightly below the limit at which landfilling would be permitted at a... 

The thermal treatment of some wastes (e.g. industrial, medical, and military) through their incineration results in the formation of relatively highly toxic residues. The ash residue being a secondaiy waste is sometimes more toxic than the primary solid feed. 

Waste may be stabilized or solidified by either thermal or non thermal treatments. Thermal treatments are ideal for destmction of organic contaminants. They reduce the volume of the waste and, hence, disposal costs. They are, however, energy intensive and more expensive than nonthermal methods, and release volatile elements that need to be contained. If the waste stream contains inorganic contaminants, the residue left after the thermal treatment is often more concentrated in these contaminants because they cannot be destroyed by such treatment. They also contaminate equipment such as furnaces and filters used during the treatment, which also ultimately need proper disposal. Thus, there is... 

A. Homung, S. Donner, A. Balabanovich and H. Seifert, Dehalogenation of electronic waste and corresponding pyrolysis residues, 22nd International Conference on Incineration and Thermal Treatment Technologies (ITS), Orlando, Florida., 12-16, (2003). 

Solid residues with final storage quality should have properties very similar to the Earths crust (natural sediments, rocks, ores, soil). This can be achieved in several ways, for example by assortment or thermal, chemical and biological treatment. In most cases, this standard is not attained by simple incineration of municipal solid waste - that is, by only the reduction of organic fractions. There is, in particular, the problem of easily soluble minerals such as sodium chloride. Future efforts should be aimed at optimizing the incineration process in a sense that critical components are concentrated in the filter ash and in the washing sludge, whereas the quality of the bottom ash is improved in such a way that deposition is facilitated and even reuse of this material is possible due to either the low concentrations or chemically inert bonding forms of metals. 

The solid wastes are primarily scrap metal from destruction of the munition bodies, bursters, and fuzes. The release level for this material is <1VSE. If problems arise with residual mustard contamination in the scrap metal, the metal could be decontaminated by thermal treatment in the main plant. 

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