Thermodynamic equilibrium predictions of zinc volatilization, migration, and transformation during sludge co‐incineration

Abstract

The effects of interactions between and among chlorine (Cl), sulfur (S), phosphorus (P), and minerals on migration, transformation, and volatilization of zinc (Zn) were numerically simulated in sludge co-incineration using the chemical thermodynamic equilibrium method. Our results showed that all the minerals of Fe 2 O 3 , Al 2 O 3 , Fe 2 O 3 , and TiO 2 except for CaO in the sludge co-incineration system reacted with Zn which inhibited the Zn volatilization. The presence of S and P was beneficial to the formation of ZnSO 4 (s) and Zn 3 (PO 4 ) 2 (s). Cl weakened the chemical reactions between the minerals and Zn, thus increasing the Zn volatilization. Changes in Zn transformation and migration induced by the coupling of Cl + S were mainly controlled by Cl, S, and the minerals, while those induced by Cl + P and S + P were mainly controlled by P and S + P. The presence of P + Cl, S + Cl, S + P, S + Cl + P, Cl, and Al 2 O 3 in the coexisting mineral system controlled the reactions between the minerals and Zn.

Eco-friendly design of complex refractory aggregates as alternatives to the magnesia-chromite ones

“…Thus, no remarkable changes in the solidification defects generated after the electrofusion process are expected. At first, it is worth noticing that no Zn-containing system was selected, which is attributed to the high partial pressure of this element [45], resulting in gas formation at temperatures close to 2400 ºC. Secondly, all selected compositions presented Fe additions, which was observed to display a similar role of Cr, also presenting a high solubility in periclase at high temperatures (72 wt% at 1718 ºC) and able to exsolve a spinel structure during cooling.…”