Plasma is the fourth state of matter, an ionized gas that is created from an electrical discharge and which can meet extreme heats, as hot as the surface of the Sun.
Much like an arc-welding machine, a plasma arc is formed when an electrical arc between two electrodes creates a high temperature, highly-ionized gas. A thermal plasma field then forms in an enclosed chamber. Finally, an electric current enters a low pressure gas stream that can heat to as high as 15,000°C. This is what is called a PLASMA TORCH.
Currently, Europlasma's plasma technology consists of two tubular metal electrodes connected to a swirling gas injection chamber. Test sessions have shown that the torch can be fed with almost any gas mixture (air, Ar, CO, helium, CO2, H2, N2, CH4, O2).
Arc ignition is obtained through short-circuit. The resulting plasma plume temperature is typically around 4000°K, while its mean enthalpy is in the range of 5 MJ/kg air to 8 MJ/kg air. To increase electrode lifetime, a time-varying magnetic field controls the upstream arc root motion, while gas injection naturally controls the downstream one.
Electrodes and injection chamber are cooled by pressurized, de-ionized water. From the process standpoint, non-transferred plasma technology offers significant advantages:
high thermal efficiency;
flexibility regarding the choice of gas to ionize;
rapidity and flexibility to start and stop the system automatically when necessary;
total independence for plasma generation between torch and furnace, which
makes for very easy operating conditions;
less vaporization due to absence of a "hot spot", the arc root attached to the slag;
operating flexibility: 25 to 100% of the power range;
