Why is coke used in the extraction of iron?
The role of coke in the extraction of iron from its oxides is that it reduces the iron oxide to molten iron metal. Coke also when burnt in the blast furnace, supplies the heat required for carrying out the extraction of iron from its oxide.
How coke is used in extraction of metals?
Extracting iron from iron ore using a Blast Furnace. The common ores of iron are both iron oxides, and these can be reduced to iron by heating them with carbon in the form of coke. Coke is cheap and provides both the reducing agent for the reaction and also the heat source.
What is the role of coke in metallurgical process?
Answer: Metallurgical coke, along with iron ore and limestone, is layered into a blast furnace to convert the iron ore to metallic iron. Coke, which is mostly carbon, reacts with the blast air to produce carbon monoxide, which, in turn, reacts with the iron oxide to produce carbon dioxide and metallic iron.
How are metal extracted?
Metals can be extracted from ores by reduction – the removal of oxygen or forming a metal element from a compound. Oxidation and reduction have multiple meanings, not just to do with the addition and removal of oxygen. Encourage students to use key terms as often as possible.
Is coal tar used in metal extraction?
Like charcoal, it Is a good fuel and burns without smoke. It is largely employed as a reducing agent in the extraction of metals from their ores. It is also used in making fuel gases like water gas and producer gas. (2) Coal tar (liquid): Coal tar is a mixture of different carbon compounds.
What is a better fuel coal or coke?
Coke is a better fuel than coal because; -Coke produces more heat on burning than coal. -Coke has a higher calorific value than coal. When equal masses of coke and coal are burnt, coke produces more heat.
How is coke used in the blast furnace process?
Blast furnace ironmaking makes use of coke as the major source for both energy and reduction of iron oxides. In the blast furnace process, coke has multifunctions and plays an important role as reductant, burden support, and fuel.
What are the characteristics and uses of coke?
Coke is a grey, hard, and porous fuel with a high carbon content and few impurities, made by heating coal or oil in the absence of air—a destructive distillation process. It is an important industrial product, used mainly in iron ore smelting, but also as a fuel in stoves and forges when air pollution is a concern.
How is coke being replaced in steel making?
On the other hand, more and more coke is being replaced with PCI and injection of oil and other secondary fuels such as waste plastics and biomass.
What happens when coal is burned in a coke oven?
When coal was burned in a coke oven, the impurities of the coal not already driven off as gases accumulated to form slag, which was effectively a conglomeration of the removed impurities. Since it was not the desired coke product, slag was initially nothing more than an unwanted by-product and was discarded.
Where does the impurities in slag come from?
The slag consists primarily of the impurities from the iron ore (chiefly silica and alumina) combined with calcium and magnesium oxides from the flux stone. Sulfur and ash that may come from the coke will also be contained in the slag, which comes from the furnace as a liquid at temperatures about 1500°C.
Which is the best way to treat a slag?
Slags are sometimes treated by slow cooling, milling, and flotation. This approach is satisfactory when the metals in the slag are in either the sulphide or metallic form, but is not suitable for the recovery of oxidized metals.
Coke is a grey, hard, and porous fuel with a high carbon content and few impurities, made by heating coal or oil in the absence of air—a destructive distillation process. It is an important industrial product, used mainly in iron ore smelting, but also as a fuel in stoves and forges when air pollution is a concern.
What happens when you use a hot blast on Coke?
Using a hot blast produces a shorter and hotter combustion zone. Melting occurs higher in the combustion zone as hotter metal droplets remain in contact with hotter incandescent coke. These factors combine to produce with a constant charge: 1. a reduction in coke consumption; 2. 3. 4. increased metal temperature.
