What is the reaction in the converter during oxygen blowing?
Reactions in the converter
O2 reacts with the dissolved Si, dissolved Mn, and the Fe itself to make a liquid FeO-containing slag. The O2 also reacts with the dissolved C to liberate CO gas and thereby decarburize the iron.
How does a basic oxygen converter work?
During the process, oxygen is blown into a BOF converter containing liquid hot metal containing high carbon content. The oxygen combines with the dissolved carbon to form CO, which then escapes as gas. Thus, the hot metal is transformed into liquid steel with a low carbon content.
What metals are processed in the oxygen converter?
basic oxygen process (BOP), a steelmaking method in which pure oxygen is blown into a bath of molten blast-furnace iron and scrap. The oxygen initiates a series of intensively exothermic (heat-releasing) reactions, including the oxidation of such impurities as carbon, silicon, phosphorus, and manganese.
What is LD process?
The Linz-Donawitz (LD) process, developed in Austria in 1949, blew oxygen through a lance into the top of a pear-shaped vessel similar to a Bessemer converter. Since there was no cooling effect from inert nitrogen gas present in air, any heat not lost to the off-gas…
What is difference between blast furnace and basic oxygen furnace?
Blast furnace-basic oxygen furnace uses iron ore as its base raw material that accounts over just 50% of BOF steel costs, and electric arc furnace uses scrap as its base that represents around 75% of EAF steel cost. The Basic Oxygen Steelmaking process differs from the EAF is that BOF is self-sufficient in energy.
Which oxygen is used for blast furnace operations?
More than half the world’s steel is produced in the basic oxygen process (BOP), which uses pure oxygen to convert a charge of liquid blast-furnace iron and scrap into steel.
What is blast furnace process?
blast furnace, a vertical shaft furnace that produces liquid metals by the reaction of a flow of air introduced under pressure into the bottom of the furnace with a mixture of metallic ore, coke, and flux fed into the top.
Why oxygen is used for BOF?
The BOF process is autogenous, or self sufficient in energy, converts liquid iron (hot metal) into steel using gaseous oxygen (O2) to oxidize the unwanted impurities in hot metal (HM). The O2 used must be of high purity, usually 99.5% minimum, otherwise the steel may absorb harmful nitrogen (N2).
Which is a major advantage of LD process?
(A) the process is very quick. (B) operating costs are low. (C) better quality steel is obtained. (D) scrap iron can be used.
Which oxygen is used for blast furnace operation?
What is the temperature of blast furnace?
The preheated air reacts vigorously with the preheated coke, resulting in both the formation of the reducing gas (carbon monoxide) that rises through the furnace and a very high temperature of about 1,650 °C (3,000 °F) that produces the liquid iron and slag.
Why coke is used in blast furnace?
In the blast furnace route of ironmaking, metallurgical coke are used for four main purposes: first to act as a reducing agent, second to fulfil the energy demand of the endothermic reduction reactions, third to maintain the structure and permeability inside the furnace and fourth to act as a carburiser for freshly …
What fuel is used in blast furnace?
metallurgical coke
The iron blast furnace uses carbon as a fuel to meet the energy requirements of the process as well as a reducing agent for smelting the iron ore to pig iron. The most widespread form of carbon used for this purpose is metallurgical coke.
How are impurities removed in the basic oxygen process?
During the BOS process, impurities in HM such as C, silicon (Si), manganese (Mn), phosphorus (P) etc. are removed by oxidation for the production of liquid steel. Oxidation is carried out with high purity O2 gas which is blown in the converter.
Why oxygen is used in steel plant?
Oxygen is used to increase ferromanganese production and to decrease the specific fuel consumption. In cupolas oxygen permits faster melting rates. It is concluded that more extensive use will be made of oxygen in the future.
Why limestone is added in blast furnace?
Limestone is also used to remove impurities from the blast furnace when making iron. The impurities are mostly silicon dioxide (also known as sand). The calcium carbonate in the limestone reacts with the silicon dioxide to form calcium silicate (also known as slag).
Why coal is not used in blast furnace?
Coal cannot be directly charged via the furnace top, it must first be transformed to coke. Raw materials are charged to the furnace in alternating layers of coke and ore. This alternating layer structure inside the furnace has a profound impact on the operation of the furnace and on the required quality of coke.
What is F value in blast furnace?
This equation contains an “F-factor”, which, for a particular fuel, is the volume of flue gas (in dry, standard cubic feet) produced for every million Btu of heat input. Conventional fuels such as coal, fuel oil, and natural gas have well-established F-factors (see Table 1 in Appendix F of Part 75).
How much co2 does a blast furnace produce?
But blast furnaces produce an incredible amount of carbon dioxide. A recent study showed that 252.5 million tons of CO2 was produced in the period from 2005-2008. Putting it another way, blast furnaces produce between four and seven percent of all the man-made CO2 in the world. This is an effect that cannot be ignored.
How do you remove oxygen from steel?
Vacuum deoxidation is a method which involves using a vacuum to remove impurities. A portion of the carbon and oxygen in steel will react, forming carbon monoxide. CO gas will float up to the top of the liquid steel and be removed by a vacuum system.
What is EAF and BOF?
Most steel in Europe is produced via two basic routes: The Blast Furnace-Basic Oxygen Furnace (BF-BOF) route and the Electric Arc Furnace route (EAF). Blast furnaces produce iron from iron ore. In a second step a basic oxygen converter turns iron, with some additions of scrap, into steel.
What is the reducing agent in blast furnace?
carbon monoxide
The reducing agent in the blast furnace in the manufacturing of iron is carbon monoxide.
How much CO2 does a blast furnace produce?
What is top gas in blast furnace?
In a top gas recycling blast furnace, CO2 contained in the top gas is removed and the remaining stream, rich in reducing agents H2 and CO, is heated and re-injected into the blast furnace at two levels, the shaft and tuyeres, at different temperatures and flow rates.
How much CO2 is released per ton of steel?
1.85 tons
Every ton of steel produced in 2018 emitted on average 1.85 tons of carbon dioxide, equating to about 8 percent of global carbon dioxide emissions.