The fumes produced in “flameless” combustion are very pure, and consist essentially of CO2 and water vapour; however if the treated material contains halogens, (Clorine, etc.) or sulphur, the fumes are acidic because of the sulphur hydride or hydrochloric acid; in this case treatment is carried out in accordance with simple traditional techniques.

Once the acidic components have been eliminated the water is condensed and the fumes, at high CO2 concentration, are available for possible industrial use.

In several applications, particularly that of “the treatment of contaminated ground” or, more generally speaking, of industrial toxic waste, the material for treatment abounds in heavy metals (lead, vanadium, molybdenum, etc.) whose treatment in combustion or in traditional treatments is particularly complex and costly; in certain cases, actually even hinders the use of potential fuels rich in heavy metals. In the Isotherm® process, for each heavy metal, a fraction go in the fumes and the remaining fraction go in the slag; the fraction that goes in the fumes depends on the metal; several heavy metals go almost totally to the slag, others are divided between the two, while few others (mercury) go almost totally into the fumes. The fraction in the slag remains inert in the vitreous matrix and in no way compromises its industrial use; the part that goes into the fumes is treated in an appropriate column, provided for in the fumes treating section, where the remaining heavy metals are separated out with a process, patented by Itea, applicable to the entire heavy metal spectrum, including those present as nano-particles.