Liquid slag

The production of copper from sulphide minerals is accomplished with a preliminary partial roast of die sulphides before reaction widr air in the liquid state, known as mattes, to form copper metal (conversion). The principal sources of copper are minerals such as chalcopyrite, CuFeSa and bornite CuaFeSa, and hence the conversion process must accomplish the preferential oxidation of non, in the form of FeO, before the copper metal appears. As mentioned before, tire FeO-SiOa liquid system is practically Raoultian, and so it is relatively easy to calculate the amount of iron oxidation which can be canned out to form this liquid slag as a function of the FeO/SiOa ratio before copper oxidation occurs. The liquid slag has a maximum mole fraction of FeO at the matte blowing temperatures of about 0.3, at solid silica saturation. 

The production of metals which form very stable oxides by tire aluminothermic process, such as manganese, clrromium and vanadium is carried out with reactants at room temperature which react to provide enough heat to raise the temperature of the products to high temperatures at which the whole system is liquid. The metal phase which is produced can therefore separate from the liquid slag which is formed. The production of clrromium serves as a useful... 

Quicklime is produced in enormous quantities throughout the world. About 40% of this output is used in metallurgy. In ironmaking (Section 16.13), it is used as a Lewis base its O2- ion reacts with silica, Si02, impurities in the ore to form a liquid slag ... 

Air-cooled blast furnace slag. If the liquid slag is poured into beds and slowly cooled under ambient conditions, a crystalline structure is formed, and a hard, lump slag is generated, which can subsequently be crushed and screened. 

Andco-Torrax A process for making a fuel gas by the partial oxidation of organic wastes in a vertical shaft furnace. The residue is removed as a liquid slag from the base of the furnace. 

Combustion of char or feedstock produces ash, unreacted organic material, which can be melted into liquid slag. Slag can be resolidified to form clinker. 

A liquid slag is formed, which is mainly calcium silicate. More details of the extraction of iron and its conversion into steel are given in Chapter 10. 

Immiscible liquids constitute separate phases (e.g., liquid slag and metal in a furnace)... 

The silicates formed in reactions 2 and 3 fuse with the added fluxes to form a liquid slag at which point carbon monoxide loses its effectiveness as a reducing agent. Unreacted carbon from the fuel then becomes the predominant reductant in reducing both stannous silicate to tin and ferrous silicate to iron. The metallic iron, in turn, reduces tin from stannous silicate ... 

The Metallurgy of Iron. The ores of iron are usually first roasted, in order to remove water, to decompose carbonates, and to oxidize sulfides. They are then reduced with coke, in a structure called a blast furnace (Fig. 26-2). Ores containing limestone or magnesium carbonate are mixed with an acidic flux (containing an, excess of silica), such as sand or clay, in order to make a liquid slag. Limestone is used as flux for ores containing an excess o silica. The mixture of ore, flux, and coke is introduced at the top of the blast furnace, and pre heated air is blown in at the bottom through tuyeres. As the solid... 

The thermodynamic data used in the present modelling have been taken from the extensive file store of GTT-Technologies. One hundred and nine phases and altogether 202 species have been included in the calculations. The gas phase (60 species) has been treated as ideal, while the liquid Fe phase (dilute solution approach, 14 species) and the liquid slag (Gaye-Kapoor-Frohberg model, eight species) have been treated as non-ideal chemical solutions. 

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