US2025179594A1PendingUtilityA1
Method for producing molten pig iron
Est. expiryMar 7, 2042(~15.6 yrs left)· nominal 20-yr term from priority
C21B 2100/00C21B 2100/26C22B 1/02C22B 1/24C22B 1/16C21B 7/00C21B 7/002C21B 5/008C21B 2100/22C21B 2100/282C21B 11/02C21B 5/06
54
PatentIndex Score
0
Cited by
0
References
0
Claims
Abstract
A method for producing molten pig iron includes a first step of producing carbon-material-containing agglomerated ore from an iron-containing and carbon-containing raw materials, a second step of blowing an oxygen-containing gas into the carbon-material-containing agglomerated ore to reduce and melt it, thereby producing molten pig iron, and a third step of bringing a carbon-containing gas containing carbon monoxide and carbon dioxide produced as a by-product of the reduction into contact with a porous material, thereby recovering carbon, in which in the first step, the carbon recovered in the third step is used for a part of or an entirety of the carbon-containing raw material. The method may include, instead of the second step, a reduction step of heating the carbon-material-containing agglomerated ore to 1160 to 1450° C., and then cooling the carbon-material-containing agglomerated ore to obtain reduced iron, and a step of melting the reduced iron to produce molten pig iron.
Claims
exact text as granted — not AI-modified1 . A method for producing molten pig iron, comprising:
a first step of producing a carbon-material-containing agglomerated ore from an iron-containing raw material and a carbon-containing raw material; a second step of blowing an oxygen-containing gas into the carbon-material-containing agglomerated ore to reduce and melt the carbon-material-containing agglomerated ore, thereby producing molten pig iron; and a third step of bringing a carbon-containing gas containing carbon monoxide and carbon dioxide produced as a by-product of the reduction into contact with a porous material, thereby recovering carbon, characterized in that: in the first step, the carbon recovered in the third step is used for a part of or an entirety of the carbon-containing raw material.
2 . The method for producing molten pig iron according to claim 1 , comprising, instead of the second step:
a reduction step of obtaining reduced iron in which the carbon-material-containing agglomerated ore is heated to 1160 to 1450° C., reduced, melted, and then cooled, and a melting step of producing molten pig iron in which the reduced iron is melted.
3 . The method for producing molten pig iron according to claim 1 , wherein in the third step, the carbon-containing gas further contains a gas containing carbon monoxide and carbon dioxide produced as a by-product of a refining step of molten iron.
4 . The method for producing molten pig iron according to claim 1 , further comprising, before bringing the carbon-containing gas into contact with the porous material in the third step, supplying hydrogen to the carbon-containing gas and heating the carbon-containing gas to 800 to 1200° C. to convert the carbon dioxide contained in the carbon-containing gas to carbon monoxide.
5 . The method for producing molten pig iron according to claim 4 , further comprising, after heating the carbon-containing gas but before bringing the carbon-containing gas into contact with the porous material in the third step, removing water contained in the carbon-containing gas.
6 . The method for producing molten pig iron according to claim 5 , comprising removing water contained in the carbon-containing gas and water generated through a reforming reaction of the carbon-containing gas so as to satisfy the following expression (1):
[
Math
.
1
]
[
H
2
O
]
/
(
[
H
2
O
]
+
[
H
2
]
)
<
0.1
(
1
)
where [H 2 O] represents a water concentration (volume %) in a reformed mixed gas, and [H 2 ] represents a hydrogen concentration (volume %) in the reformed mixed gas.
7 . The method for producing molten pig iron according to claim 1 , wherein in the third step, the porous material is iron, and a part of the recovered carbon is iron carbide.
8 . The method for producing molten pig iron according to claim 1 , wherein a particle size of the carbon-containing raw material is 100 μm or less.
9 . The method for producing molten pig iron according to claim 1 , wherein in the first step, the carbon-containing raw material further contains biomass.
10 . The method for producing molten pig iron according to claim 1 ,
wherein: the iron-containing raw material is iron ores, and the method further comprises a pretreatment step of subjecting the iron ores to heat treatment in a temperature range of 300° C. to 1000° C. before the first step.
11 . The method for producing molten pig iron according to claim 2 , wherein in the third step, the carbon-containing gas further contains a gas containing carbon monoxide and carbon dioxide produced as a by-product of a refining step of molten iron.
12 . The method for producing molten pig iron according to claim 2 , further comprising, before bringing the carbon-containing gas into contact with the porous material in the third step, supplying hydrogen to the carbon-containing gas and heating the carbon-containing gas to 800 to 1200° C. to convert the carbon dioxide contained in the carbon-containing gas to carbon monoxide.
13 . The method for producing molten pig iron according to claim 3 , further comprising, before bringing the carbon-containing gas into contact with the porous material in the third step, supplying hydrogen to the carbon-containing gas and heating the carbon-containing gas to 800 to 1200° C. to convert the carbon dioxide contained in the carbon-containing gas to carbon monoxide.
14 . The method for producing molten pig iron according to claim 11 , further comprising, before bringing the carbon-containing gas into contact with the porous material in the third step, supplying hydrogen to the carbon-containing gas and heating the carbon-containing gas to 800 to 1200° C. to convert the carbon dioxide contained in the carbon-containing gas to carbon monoxide.
15 . The method for producing molten pig iron according to claim 12 , further comprising, after heating the carbon-containing gas but before bringing the carbon-containing gas into contact with the porous material in the third step, removing water contained in the carbon-containing gas.
16 . The method for producing molten pig iron according to claim 13 , further comprising, after heating the carbon-containing gas but before bringing the carbon-containing gas into contact with the porous material in the third step, removing water contained in the carbon-containing gas.
17 . The method for producing molten pig iron according to claim 14 , further comprising, after heating the carbon-containing gas but before bringing the carbon-containing gas into contact with the porous material in the third step, removing water contained in the carbon-containing gas.
18 . A method for producing molten pig iron according to claim 15 , comprising removing water contained in the carbon-containing gas and water generated through a reforming reaction of the carbon-containing gas so as to satisfy the following Expression (1):
[
Math
.
1
]
[
H
2
O
]
/
(
[
H
2
O
]
+
[
H
2
]
)
<
0.1
(
1
)
where [H 2 O] represents a water concentration (volume %) in a reformed mixed gas, and [H 2 ] represents a hydrogen concentration (volume %) in the reformed mixed gas.
19 . A method for producing molten pig iron according to claim 16 , comprising removing water contained in the carbon-containing gas and water generated through a reforming reaction of the carbon-containing gas so as to satisfy the following Expression (1):
[
Math
.
1
]
[
H
2
O
]
/
(
[
H
2
O
]
+
[
H
2
]
)
<
0.1
(
1
)
where [H 2 O] represents a water concentration (volume %) in a reformed mixed gas, and [H 2 ] represents a hydrogen concentration (volume %) in the reformed mixed gas.
20 . A method for producing molten pig iron according to claim 17 , comprising removing water contained in the carbon-containing gas and water generated through a reforming reaction of the carbon-containing gas so as to satisfy the following Expression (1):
[
Math
.
1
]
[
H
2
O
]
/
(
[
H
2
O
]
+
[
H
2
]
)
<
0.1
(
1
)
where [H 2 O] represents a water concentration (volume %) in a reformed mixed gas, and [H 2 ] represents a hydrogen concentration (volume %) in the reformed mixed gas.Join the waitlist — get patent alerts
Track US2025179594A1 — get alerts on status changes and closely related new filings.
We store only your email — no account needed. See our privacy policy.