Thermodynamic aspects of dioxin precursors neutralization by plasma methods

The problem of increasing the efficiency of thermal methods for waste disposal due to the plasma methods introduction at the stage of toxic gaseous afterburning is considered. Dioxins, synthetic organic substances from the class of chlorocarbons, are by far the most toxic substances produced by humans. The main source of their formation is incineration plants, pulp and paper, electrical industry, etc. In addition, the formation of dioxins can lead to the interaction under certain conditions of some organic compounds – precursors of dioxins. Taking into account these circumstances, we consider the reactions that characterize the processes of high-temperature neutralization of dioxin precursors – chlorobenzene, phenol, biphenyl, and trichloroethylene. On the basis of thermodynamic analysis, a high probability of their spontaneous oxidation and decomposition at temperatures above 500 K is shown. The decomposition efficiency increases with increasing temperature, thereby confirming the possibility of these products neutralization under plasma heating conditions. The scheme of the plasma afterburning technology and the results of the heating temperatures calculation for toxic gases in the mixing chamber of the plasma torch are shown. The results indicate that plasma heating provides the temperature range necessary for the effective decomposition of dioxin precursors.