The present invention relates to a method and apparatus for producing reduced iron from ironmaking dust which contains iron oxide which is generated at an ironmaking plant, takes note of the rotary kiln reduction method which does not require pretreatment of the dust, and has as its problem the pursuit of facilities which achieve further improvement of heat efficiency and stable operation.

To solve this problem, the present invention is characterized by heating and reducing carbon-containing shaped materials in a single closed space in which an internal heat type rotary kiln and an external heat type rotary kiln are arranged in series and including at least the insides of the two rotary kilns during which making the reduced exhaust gas which is generated at the external heat type rotary kiln burn inside of the internal heat type rotary kiln.

A method of processing iron ore fines from various possible sources, with particle size up to 0.15 mm (through 100 mesh sieve) with no or limited comminution, directly into the intense mixer, with a set of binders in specific proportions, aiming to optimize physical and metallurgical properties of the pellets with minimal binder addition, thus not compromising the quality of steel products. The binders are starch, sodium silicate and sodium hydroxide, among others. The mixture with adjusted moisture content goes through conventional balling discs or drums and size screening. The green pellets then undergo drying with forced air at around 150° C. for a short time. The pellets obtained have excellent metallurgical properties, and compression resistance around 70 kgf/pellets, without the high and undesirable economic and environmental costs of the conventional indurating process. An alternative embodiment (FIG. 3) considers indurating the pellets at temperatures below 1,200° C. to obtain similar mechanical resistance than pellets made by the conventional induration process, with temperatures above 1,300° C.

A smelting method capable of obtaining an iron-nickel alloy having a high nickel grade of 4% or higher by effectively facilitating a reduction reaction of pellets formed using a nickel oxide ore as a raw material. The present invention is a method for smelting a nickel oxide ore, by which an iron-nickel alloy is obtained by forming pellets from a nickel oxide ore and reducing and heating the pellets. In the pellet production step S1, a mixture is obtained by mixing raw materials that contain at least a nickel oxide ore and a carbonaceous reducing agent. In the reduction step S2, a furnace floor carbonaceous reducing agent is laid on the floor of the smelting furnace in advance when placing the obtained pellets in the smelting furnace and the pellets are placed on the furnace floor carbonaceous reducing agent and then reduced and heated.

The present invention concerns the use of a magnesium-including compound as binder for producing metallic ore fluxed pellets, in particular iron ore fluxed pellets, said magnesium-including compound comprising semi-hydrated dolime fitting the general formula aCa(OH).sub.2.Math.bMg(OH).sub.2.Math.cMgO, a, b, and c being weight fractions wherein the weight fraction b of Mg(OH).sub.2 is between 0.5 and 19.5 % by weight with respect to the total weight of said semi-hydrated dolime.

The efficiency of roasting black dross can be improved by pre-processing the black dross before roasting. Black dross can be crushed and reconstituted into pellets having internal channels. The internal channels can be filled with additives designed to fully oxidize during a dross roasting process, enabling the internal channels to be open and gas to flow therethrough during a dross roasting process. The crushed black dross can be crushed to pieces below 10 mm and screened for larger pieces prior to pelletizing to ensure consistent pellets. Optionally, an eddy current separator can remove some metallic aluminum from the crushed black dross prior to pelletizing.

A DRI product and method of forming the DRI product. DRI is formed from a reducing process, and thereafter the DRI is subjected to another heat treatment that produces a DRI product. The DRI product formed has a metallic shell around at least a portion of a DRI core. The heat treatment may be delivered through the use of a plasma torch, a gas burner, an oven, or any other like heat source. The heat treatment may heat the DRI for a fraction of a second and quickly cool the DRI in order to melt the surface and form the metallic shell without vaporizing a significant portion of the DRI and without losing a significant amount of the latent energy in the DRI.

A method for producing briquettes from pellet fines, DRI sludge, DRI fines and dust from DRI dedusting systems and, in this way, reincorporating same into steel production processes, thereby contributing to the re-use of the by-products of these processes, as well as minimizing the stocks of these types of materials and, consequently, helping to improve the environment. The invention comprises: grinding and sieving the pellet fines and the DRI sludge; sieving the DRI fines; storing the dust from DRI dedusting systems; briquetting with roller presses, using liquid sodium silicate and bentonite or composite Portland cement as binders; sieving the briquettes; shredding the edges and waste of the fresh briquettes; and curing in order to improve the physical properties thereof, such as strength. Once cured, the fresh briquette can be stored or sent directly to direct-reduced iron production processes for use as part of the feedstock for reduction ovens or reactors.

According to the invention, a method for treating electronic waste with a view to individually recovering metals included in such waste is provided. Said method is characterized in that it includes the series of the following steps: grinding the waste under conditions suitable for individually separating the different metal components of the waste; mixing the ground waste with a liquid such as to form a suspension; gravitationally separating the suspension such as to separate the particles having the highest densities and containing the majority of the metals from the particles having the lowest densities; and densimetrically separating the suspension containing the majority of the metals such as to obtain suspensions containing the individually separated metals.

A method of extracting lithium from a lithium-bearing material including:

(i) mixing the lithium-bearing material, gypsum, a sulfur-containing material, and a calcium-containing material and forming a feed mixture having a moisture content of at least 20 wt %;

(ii) drying the feed mixture to form a dried mixture having a moisture content of less than 20 wt %;

(iii)roasting the dried mixture and forming a roasted mixture including a water-soluble lithium compound; and

(iv) leaching lithium from the water-soluble lithium compound and forming a lithium-containing leachate by mixing the aqueous solution and the water-soluble lithium compound.

Various embodiments relate to several processes that may recover commodity chemicals from an alkaline metal-air battery. In various embodiments, while the cell is operating, various side products and waste streams may be collected and processed to regain use or additional value. Various embodiments also include processes to be performed after the cell has been disassembled, and each of its electrodes have been separated such as not to be an electrical hazard. The alkaline metal battery recycling processes described herein may provide multiple forms of commodity iron, high purity transition metal ores, fluoropolymer dispersions, various carbons, commodity chemicals, and catalyst dispersions.