The present invention relates to a sealed plasma melting furnace for treating low- and intermediate-level radioactive waste, which allows the secondary pollutants to be minimized. The sealed plasma melting furnace includes: a waste supply chamber communicatively provided with a hopper; a pyrolysis chamber channel communicatively coupled with the waste supply chamber; a pyrolysis chamber having a burner mounted thereon; a melting chamber channel guiding the waste transferred from the pyrolysis chamber communicatively provided therewith to fall down; a melting chamber provided with a furnace interior portion accommodating a molten substance on a bottom surface thereof; a processed molten substance discharge channel discharging the processed molten substance generated in the melting chamber; a secondary combustion chamber channel inducing and exhausting an off-gas flow generated in the melting chamber; and a secondary combustion chamber inducing complete combustion of the off-gas input from the secondary combustion chamber channel.

The method according to the invention enables a facility having a rather reduced dimension, for incinerating to be used, melting and vitrifying mixed waste (30) introduced into a reactor (10), by means of a basket (18) in turn passing through an air lock (12). Plasma torches (14) burn all waste (30) contained in the basket (18). The waste is then lowered in a melting bath of a furnace (20) with an inductor (24) including a crucible-forming container (23). A combustion gas treatment train completes the facility. The furnace (20) can be dismantled, after a series of treatments of several baskets (18) of waste (30) for disassembling the crucible-forming container (23) from the furnace (20). Application in treating different radiologically contaminated and/or toxic mixed waste.

The present invention relates to a plasma furnace capable of separating and discharging different kinds of molten material, which comprises a furnace body 110; and a heating portion 140 for heating the lateral discharge gate 120, 130, wherein the furnace body comprises a melt discharge portion formed through a lower portion of the melting chamber 101 provided for accommodating molten material; and at least two lateral discharge gates 120, 130 provided at different heights capable of discharging molten material.

The present invention relates to a plasma furnace which can efficiently treat various types of waste in large amounts. The plasma furnace comprises a melting chamber 101 for accommodating a melt, an upper surface forming the upper portion of the melting chamber 101 with a horizontal upper surface 111 and an inclined upper surface 112 having a slope with respect to the horizontal upper surface 111, a melt discharge portion 130 formed through a bottom surface of the melting chamber for discharging molten material therethrough, and an input apparatus 120 having a slope for inputting waste into the melting chamber 101, and the mixed type plasma torch 191, 192 provided on the inclined upper surface 112 with a slope for generating melting heat in the melting chamber 101.

For continuously casting an ingot of titanium or titanium alloy, molten titanium or titanium alloy is poured into a top opening of a bottomless mold with a circular cross-sectional shape, the solidified molten metal in the mold is pulled downward from the mold, a plurality of plasma torches disposed on an upper side of molten metal in the mold such that their centers are located directly vertically above the molten metal in the mold, are operated to generate plasma arcs that heat the molten metal in the mold, and the plasma torches are moved in a horizontal direction above a melt surface of the molten metal in the mold, along a trajectory located directly vertically above the molten metal in the mold, while keeping a mutual distance between the respective plasma torches such that the plasma torches do not interfere with each other.

A method for recovery of evaporable substances comprises melting (210) of a material comprising evaporable metals and/or evaporable metal compounds into a molten slag. The molten slag is agitated (212) by a submerged jet of hot gas. The hot gas is controlled (214) to have an enthalpy of at least 200 MJ/kmol, and preferably at least 300 MJ/kmol. At least a part of the evaporable metals and/or evaporable metal compounds are fumed off (216) from the molten slag. An arrangement for the method is based on a furnace with a plasma torch submerged into molten slag in the furnace.

The invention relates to a hybrid process and a hybrid device for the production or thermal treatment of inorganic raw substances or materials in combination with further organic additives with the use of at least one gas burner in combination with at least one plasma burner in a furnace facility.

An arrangement for heat transfer to a melt in a tundish in a continuous casting process, wherein the tundish includes at least one outlet and an inlet, the arrangement including a heating chamber, a plasma heating apparatus including a plasma torch positioned inside the heating chamber, wherein the plasma heating apparatus is mounted on an arm and arranged to operate through a hole in the heating chamber with a distance to the melt and an electromagnetic stirrer placed outside of the heating chamber and arranged to electromagnetically stir the melt. The heating chamber further includes a pair of weirs installed at an upper part of the heating chamber and a pair of dams installed at a lower part of the heating chamber and the electromagnetic stirrer is arranged to electromagnetically stir the melt in a region of the heating chamber, wherein the region is enclosed by the weirs and dams.

A system and method for melting a raw material. The raw material is fed into an electrically conductive vessel. A plasma arc torch melts at least some of the raw material within the vessel to thereby create a molten material. An inductor, physically disposed adjacent the vessel, and electrically disposed in series with the vessel in operation, effects electromagnetic stirring of the molten material by interacting with the current of the plasma arc torch.

For continuously casting an ingot of titanium or titanium alloy, molten titanium or titanium alloy is poured into a top opening of a bottomless mold with a circular cross-sectional shape, the solidified molten metal in the mold is pulled downward from the mold, a plurality of plasma torches disposed on an upper side of molten metal in the mold such that their centers are located directly vertically above the molten metal in the mold, are operated to generate plasma arcs that heat the molten metal in the mold, and the plasma torches are moved in a horizontal direction above a melt surface of the molten metal in the mold, along a trajectory located directly vertically above the molten metal in the mold, while keeping a mutual distance between the respective plasma torches such that the plasma torches do not interfere with each other.