摘要 |
A method for plasma treatment of wet metal-containing wastes in which a plasma treatment unit comprises an electrically conductive hearth for holding a layer of slag and optionally a layer of metal produced by the plasma treatment. A graphite electrode is arranged above the hearth, so that, in use, a plasma arc is formed between the electrode and the hearth. One or more inlets for the particulate metal-containing waste are arranged adjacent to the electrode and sufficiently close to the electrode so that, in use, the particulate metal-containing waste fed into the plasma treatment unit falls close to the arc formed between the electrode and the hearth and is heated by the plasma arc before contacting the slag layer such that moisture present in the particulate metal-containing waste is completely volatilized in a head space of the furnace. |
主权项 |
1. A method for the treatment of metal-containing waste, the method comprising:
(i) feeding a wet particulate metal-containing waste under gravity into a plasma treatment unit comprising a furnace; (ii) plasma treating the particulate metal-containing waste to form a layer of slag and, optionally, a layer of metal beneath the layer of slag; and (iii) recovering slag and/or metal from the plasma treatment unit; wherein the plasma treatment unit comprises an electrically conductive hearth for holding the layer of slag and optional layer of metal, one or more inlets for the particulate metal-containing waste arranged above the hearth, and a graphite electrode arranged above the hearth so that, in use, a plasma arc is formed between the electrode and the hearth, wherein the one or more inlets for the particulate metal-containing waste are arranged adjacent to the electrode and sufficiently close to the electrode so that, in use, the particulate metal-containing waste fed into the plasma treatment unit falls close to the arc formed between the electrode and the hearth and is heated by the plasma arc before contacting the slag layer such that moisture present in the particulate metal-containing waste is completely volatilized in a head space of the furnace above the slag layer; wherein the wet particulate metal-containing waste comprises an ore comprising a metal selected from the group consisting of iron, nickel, copper, titanium, chromium, and manganese; and a slag comprising titanium dioxide and metallic iron is recovered from the ore. |