Thermal plasma treatment has been regarded as a viable alternative for the treatment of highly toxic wastes, such as incinerator residues, radioactive wastes, and medical wastes. Therefore, a gasification/vitrification unit for the direct treatment of municipal solid waste (MSW), with a capacity of 10 tons/day, was developed using an integrated furnace equipped with two nontransferred thermal plasma torches. The overall process, as well as the analysis of byproducts and energy balance, has been presented in this paper to assess the performance of this technology. It was successfully demonstrated that the thermal plasma process converted MSW into innocuous slag, with much lower levels of environmental air pollutant emissions and the syngas having a utility value as energy sources (287 Nm3/MSW-ton for H2 and 395 Nm3/MSW-ton for CO), using 1.14 MWh/MSW-ton of electricity (thermal plasma torch (0.817 MWh/MSW-ton)+utilities (0.322 MWh/MSW-ton)) and 7.37 Nm3/MSW-ton of liquefied petroleum gas.

This paper considers particle and power balances to estimate the bulk plasma potential of a hot-filament discharge plasma produced in a multidipole plasma device. The bulk plasma potential dependence on positive dc bias applied to an anode is analyzed, and the predicted characteristics of the plasma potential are compared to the experiment. It is shown that the plasma potential can be more positive or more negative than the anode bias potential. When the potential is more negative, a steady-state potential dip in front of an anode is observed using emissive probes with the zero-emission inflection point method. Conditions for the potential dip formation are discussed.

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It is shown that the plasma potential and electron temperature of capacitively coupled RF plasmas, confined in a multi-dipole plasma device. can be varied by changing the position of a grounded plate located in the surface multi-dipole magnetic field.

Pulsed corona induced plasma chemical process (PPCP) has been investigated for the simultaneous removal of NO(x) (nitrogen oxides) and SO2 (sulfur dioxide) from the flue gas emission. It is one of the world's largest scales of PPCP for treating NO(x) and SO2 simultaneously. A PPCP unit equipped with an average 120 kW modulator has been installed and tested at an industrial incinerator with the gas flow rate of 42 000 m3/h. To improve the removal efficiency of SO2 and NO(x), ammonia (NH3) and propylene (C3H6) were used as chemical additives. It was observed that the pulsed corona induced plasma chemical process made significant NO(x) and SO2 conversion with reasonable electric power consumption. The ammonia injection was very effective in the enhancement of SO2 removal. NO removal efficiency was significantly improved by injecting a C3H6 additive. In the experiments, the removal efficiencies of SO2 and NO(x) were approximately 99 and 70%, respectively. The specific energy consumption during the normal operation was approximately 1.4 Wh/m3, and the nanopulse conversion efficiency of 64.3% was achieved with the pulsed corona induced plasma chemical process.