A method and a system is disclosed for controlling chemical reaction of a feed. The feed is directed into a reactor containing a molten metal bath to at least partially chemically react the feed to form an intermediate component. A portion of the intermediate component is combined with an off-gas which is emitted from the molten metal bath. At least a portion of the intermediate is then separated from the off-gas and returned to the molten metal bath. The returned intermediate component is then substantially converted to its atomic constituents. The atomic constituents subsequently exothermically react with other components of the molten metal bath for reaction to form compounds which are substantially stable at the operating conditions of the system, thereby allowing control of chemical reaction of the feed.
RELATED APPLICATION
This is a continuation-in-part of U.S. Ser. No. 08/023,696, filed Feb. 26, 1993, which is a divisional of U.S. Pat. No. 5,191,154, issued Mar. 2, 1993, both of which are hereby incorporated by reference.
A method of treating inorganic solid waste in a bath of molten metal contained in a vessel (3) which has a space above the bath and a waste gas outlet (11) is disclosed. The method comprises injecting waste into the bath to form a primary reaction zone (13) in which there are reactions between the waste and the bath or in which the waste undergoes a change of phase to convert the waste into more readily recoverable or disposable products. The method further comprises injecting oxygen-containing gas towards the surface of the bath to form a secondary reaction zone (17) in a section above the bath through which oxidisable products released from the primary reaction zone (13) flow to reach the waste gas outlet (11) in the vessel (3) and in which the oxidisable products are oxidised and the heat released by such oxidation is transferred into the bath.
Apparatus for the continuous heating and melting of a solid mixed waste bearing radioactive and hazardous materials to form separate metallic, slag and gaseous phases for producing compact forms of the waste material to facilitate disposal includes a copper split water-cooled (cold) crucible as a reaction vessel for receiving the waste material. The waste material is heated by means of the combination of a plasma torch directed into the open upper portion of the cold crucible and an electromagnetic flux produced by induction coils disposed about the crucible which is transparent to electromagnetic fields. A metallic phase of the waste material is formed in a lower portion of the crucible and is removed in the form of a compact ingot suitable for recycling and further processing. A glass-like, non-metallic slag phase containing radioactive elements is also formed in the crucible and flows out of the open upper portion of the crucible into a slag ingot mold for disposal. The decomposition products of the organic and toxic materials are incinerated and converted to environmentally safe gases in the melter.
A lance (5) for injecting a feed material, preferably a solid feed material, into a metallurgical vessel, is disclosed. The lance comprises: an inlet (21) for introducing the feed material into the lance; an outlet (23) at a forward end of the lance (5) for discharging the feed material from the lance (5); a hollow elongate member (25) that defines a passageway (33) for the feed material between the inlet (21) and the outlet (23) and is adapted to be cooled by a first cooling fluid; and an outer jacket (35) positioned around a section of the length of the member (25) and is adapted to be cooled by a second cooling fluid.
A method for recovering and separating precious and non-precious metals from waste streams, which removes, separates, and recovers such metals in a cost effective manner with more than 95% removal from waste streams and with minimal amounts of unprocessed solids and sludge remaining in the environment. Metals such as chromium, manganese, cobalt, nickel, copper, zinc, silver, gold, platinum, vanadium, sodium, potassium, beryllium, magnesium, calcium, barium, lead, aluminum, tin; and the like are removed and recovered from the waste streams with at least 95% removal and other metals and compounds, such as antimony, sulfur, and selenium are removed and recovered from waste streams with at least 50% removal. The method employs a unique complexing agent comprising a carbamate compound and an alkali metal hydroxide which facilitates the formation of the metals into ionic metal particles enabling them to be readily separated, removed and recovered.
A treatment apparatus (10) includes a liquid reactant metal containment vessel (11) for containing a first liquid reactant metal and isolating the reactant metal from the atmosphere. A release chamber (14) is adapted to receive the first liquid reactant metal from the containment vessel (11) and a submerging arrangement (21) is adapted to dunk or submerge a container (46) of feed material into the liquid reactant metal and move the container to a release location within the release chamber (14). Relatively light materials rising from the submerged container (46), including unreacted feed material, intermediate reaction products, and perhaps final reaction products collect in a collection area (60) having an upper surface defined by an upper surface of the release chamber (14). A treatment arrangement included in the apparatus places the fluids collected in the collection area (60) in contact with the first liquid reactant metal or a second liquid reactant metal for a sufficient period of time to effect the desired reduction reactions.
