Development of an incineration technology with plasma torch system for the melting of hazardous wastes

摘要

In the developed industry, a high proportion of hazardous wastes (PVC, asbestos, chlorinated solvents) and infection wastes are treated with thermal treatment technologies. The high temperature, high energy characteristics of plasma may be employed to convert waste materials into inert small volume products and combustible gases. Plasma torch melting(PTM) is one of the most widely used tool for the vitrification of wastes. The ash product generated is of low bulk density and may also contain leachable quantities of toxic heavy metal and organic species. Plasma processing is able to treat these ashes, destroying any contained polyaromatic hydrocarbons components. Also we presented the construction of a steady three-dimensional model of a plasma melting furnace optimum designed in this study with RNG k-ε model, and its use in characterizing the structure of the flow, temperature field and chemical species concentration. Among various types of plasma torches, non-transferred hollow cathode type torch is best suited due to its long lifetime, easy power controllability and steady power output. Development of a plasma torch showed the lifetime longer than 300 hours and efficiency better than 65%. And the various factors(electrode diameter, cooling flow rate and temperature, gas flow rate affecting the thermal efficiency of the torch) were experimentally evaluated.