Plasma Torches consist of a heating device supplied with a small inert gas flow rate which flows through an electric arc. The gas, usually Argon, undergoes the breaking of molecular and atomic bonds assuming the so called state of “plasma”, typical of the composition of the sun and stars, formed by a mixture of ions, electrons and neutral particles. The plasma reaches extremely high temperatures (7,000÷10,000°C) and it is then able to supply heat by a very high intensity radiation.
Application sectors:
• Vetrification of inorganic hazardous waste (e.g. asbestos, fly hashes from Municipal Solid Waste Incinerators)
• Thermodestruction and valorisation of organic hazardous waste (e.g. oils containing PCBs)
Advantages in the applications on waste:
• High temperatures and high thermal fluxes produced allow to accomplish heating with thermal gradients of about 1000 °C/s, generating in this way very efficient flash pyrolisis processes for the fission of complex molecules of hazardous organic waste (e.g. PCBs, pesticides) or the vetrification of inorganic hazardous waste (e.g. asbestos, fly ashes). In particular the risk of a subsequent molecule recombination with the formation of extremely toxic products, such as dioxins and furans is minimised.
• Since Plasma Torches are not burners, they do not produce flue gas and then the syngas obtained from application on organic waste consists only of the dissociated elements of the treated materials (basically Hydrogen and Carbon, in some cases converted to Carbon Monoxide) without dilution with the exhaust gas or with Nitrogen present in the air. As a consequence, the calorific value is higher; besides char and tar formation is very low.
• The high power density and the low quantity of gaseous products to be treated allow to carry out extremely compact plants, very suitable to application with low room available (i.e. ships, small islands, villages, hospitals).